1 //===---- TargetInfo.cpp - Encapsulate target details -----------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // These classes wrap the information about a call or function
10 // definition used to handle ABI compliancy.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "TargetInfo.h"
15 #include "ABIInfo.h"
16 #include "CGBlocks.h"
17 #include "CGCXXABI.h"
18 #include "CGValue.h"
19 #include "CodeGenFunction.h"
20 #include "clang/AST/Attr.h"
21 #include "clang/AST/RecordLayout.h"
22 #include "clang/Basic/CodeGenOptions.h"
23 #include "clang/Basic/DiagnosticFrontend.h"
24 #include "clang/Basic/Builtins.h"
25 #include "clang/CodeGen/CGFunctionInfo.h"
26 #include "clang/CodeGen/SwiftCallingConv.h"
27 #include "llvm/ADT/SmallBitVector.h"
28 #include "llvm/ADT/StringExtras.h"
29 #include "llvm/ADT/StringSwitch.h"
30 #include "llvm/ADT/Triple.h"
31 #include "llvm/ADT/Twine.h"
32 #include "llvm/IR/DataLayout.h"
33 #include "llvm/IR/IntrinsicsNVPTX.h"
34 #include "llvm/IR/IntrinsicsS390.h"
35 #include "llvm/IR/Type.h"
36 #include "llvm/Support/raw_ostream.h"
37 #include <algorithm> // std::sort
38 
39 using namespace clang;
40 using namespace CodeGen;
41 
42 // Helper for coercing an aggregate argument or return value into an integer
43 // array of the same size (including padding) and alignment.  This alternate
44 // coercion happens only for the RenderScript ABI and can be removed after
45 // runtimes that rely on it are no longer supported.
46 //
47 // RenderScript assumes that the size of the argument / return value in the IR
48 // is the same as the size of the corresponding qualified type. This helper
49 // coerces the aggregate type into an array of the same size (including
50 // padding).  This coercion is used in lieu of expansion of struct members or
51 // other canonical coercions that return a coerced-type of larger size.
52 //
53 // Ty          - The argument / return value type
54 // Context     - The associated ASTContext
55 // LLVMContext - The associated LLVMContext
coerceToIntArray(QualType Ty,ASTContext & Context,llvm::LLVMContext & LLVMContext)56 static ABIArgInfo coerceToIntArray(QualType Ty,
57                                    ASTContext &Context,
58                                    llvm::LLVMContext &LLVMContext) {
59   // Alignment and Size are measured in bits.
60   const uint64_t Size = Context.getTypeSize(Ty);
61   const uint64_t Alignment = Context.getTypeAlign(Ty);
62   llvm::Type *IntType = llvm::Type::getIntNTy(LLVMContext, Alignment);
63   const uint64_t NumElements = (Size + Alignment - 1) / Alignment;
64   return ABIArgInfo::getDirect(llvm::ArrayType::get(IntType, NumElements));
65 }
66 
AssignToArrayRange(CodeGen::CGBuilderTy & Builder,llvm::Value * Array,llvm::Value * Value,unsigned FirstIndex,unsigned LastIndex)67 static void AssignToArrayRange(CodeGen::CGBuilderTy &Builder,
68                                llvm::Value *Array,
69                                llvm::Value *Value,
70                                unsigned FirstIndex,
71                                unsigned LastIndex) {
72   // Alternatively, we could emit this as a loop in the source.
73   for (unsigned I = FirstIndex; I <= LastIndex; ++I) {
74     llvm::Value *Cell =
75         Builder.CreateConstInBoundsGEP1_32(Builder.getInt8Ty(), Array, I);
76     Builder.CreateAlignedStore(Value, Cell, CharUnits::One());
77   }
78 }
79 
isAggregateTypeForABI(QualType T)80 static bool isAggregateTypeForABI(QualType T) {
81   return !CodeGenFunction::hasScalarEvaluationKind(T) ||
82          T->isMemberFunctionPointerType();
83 }
84 
getNaturalAlignIndirect(QualType Ty,bool ByVal,bool Realign,llvm::Type * Padding) const85 ABIArgInfo ABIInfo::getNaturalAlignIndirect(QualType Ty, bool ByVal,
86                                             bool Realign,
87                                             llvm::Type *Padding) const {
88   return ABIArgInfo::getIndirect(getContext().getTypeAlignInChars(Ty), ByVal,
89                                  Realign, Padding);
90 }
91 
92 ABIArgInfo
getNaturalAlignIndirectInReg(QualType Ty,bool Realign) const93 ABIInfo::getNaturalAlignIndirectInReg(QualType Ty, bool Realign) const {
94   return ABIArgInfo::getIndirectInReg(getContext().getTypeAlignInChars(Ty),
95                                       /*ByVal*/ false, Realign);
96 }
97 
EmitMSVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const98 Address ABIInfo::EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
99                              QualType Ty) const {
100   return Address::invalid();
101 }
102 
isPromotableIntegerTypeForABI(QualType Ty) const103 bool ABIInfo::isPromotableIntegerTypeForABI(QualType Ty) const {
104   if (Ty->isPromotableIntegerType())
105     return true;
106 
107   if (const auto *EIT = Ty->getAs<ExtIntType>())
108     if (EIT->getNumBits() < getContext().getTypeSize(getContext().IntTy))
109       return true;
110 
111   return false;
112 }
113 
~ABIInfo()114 ABIInfo::~ABIInfo() {}
115 
116 /// Does the given lowering require more than the given number of
117 /// registers when expanded?
118 ///
119 /// This is intended to be the basis of a reasonable basic implementation
120 /// of should{Pass,Return}IndirectlyForSwift.
121 ///
122 /// For most targets, a limit of four total registers is reasonable; this
123 /// limits the amount of code required in order to move around the value
124 /// in case it wasn't produced immediately prior to the call by the caller
125 /// (or wasn't produced in exactly the right registers) or isn't used
126 /// immediately within the callee.  But some targets may need to further
127 /// limit the register count due to an inability to support that many
128 /// return registers.
occupiesMoreThan(CodeGenTypes & cgt,ArrayRef<llvm::Type * > scalarTypes,unsigned maxAllRegisters)129 static bool occupiesMoreThan(CodeGenTypes &cgt,
130                              ArrayRef<llvm::Type*> scalarTypes,
131                              unsigned maxAllRegisters) {
132   unsigned intCount = 0, fpCount = 0;
133   for (llvm::Type *type : scalarTypes) {
134     if (type->isPointerTy()) {
135       intCount++;
136     } else if (auto intTy = dyn_cast<llvm::IntegerType>(type)) {
137       auto ptrWidth = cgt.getTarget().getPointerWidth(0);
138       intCount += (intTy->getBitWidth() + ptrWidth - 1) / ptrWidth;
139     } else {
140       assert(type->isVectorTy() || type->isFloatingPointTy());
141       fpCount++;
142     }
143   }
144 
145   return (intCount + fpCount > maxAllRegisters);
146 }
147 
isLegalVectorTypeForSwift(CharUnits vectorSize,llvm::Type * eltTy,unsigned numElts) const148 bool SwiftABIInfo::isLegalVectorTypeForSwift(CharUnits vectorSize,
149                                              llvm::Type *eltTy,
150                                              unsigned numElts) const {
151   // The default implementation of this assumes that the target guarantees
152   // 128-bit SIMD support but nothing more.
153   return (vectorSize.getQuantity() > 8 && vectorSize.getQuantity() <= 16);
154 }
155 
getRecordArgABI(const RecordType * RT,CGCXXABI & CXXABI)156 static CGCXXABI::RecordArgABI getRecordArgABI(const RecordType *RT,
157                                               CGCXXABI &CXXABI) {
158   const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl());
159   if (!RD) {
160     if (!RT->getDecl()->canPassInRegisters())
161       return CGCXXABI::RAA_Indirect;
162     return CGCXXABI::RAA_Default;
163   }
164   return CXXABI.getRecordArgABI(RD);
165 }
166 
getRecordArgABI(QualType T,CGCXXABI & CXXABI)167 static CGCXXABI::RecordArgABI getRecordArgABI(QualType T,
168                                               CGCXXABI &CXXABI) {
169   const RecordType *RT = T->getAs<RecordType>();
170   if (!RT)
171     return CGCXXABI::RAA_Default;
172   return getRecordArgABI(RT, CXXABI);
173 }
174 
classifyReturnType(const CGCXXABI & CXXABI,CGFunctionInfo & FI,const ABIInfo & Info)175 static bool classifyReturnType(const CGCXXABI &CXXABI, CGFunctionInfo &FI,
176                                const ABIInfo &Info) {
177   QualType Ty = FI.getReturnType();
178 
179   if (const auto *RT = Ty->getAs<RecordType>())
180     if (!isa<CXXRecordDecl>(RT->getDecl()) &&
181         !RT->getDecl()->canPassInRegisters()) {
182       FI.getReturnInfo() = Info.getNaturalAlignIndirect(Ty);
183       return true;
184     }
185 
186   return CXXABI.classifyReturnType(FI);
187 }
188 
189 /// Pass transparent unions as if they were the type of the first element. Sema
190 /// should ensure that all elements of the union have the same "machine type".
useFirstFieldIfTransparentUnion(QualType Ty)191 static QualType useFirstFieldIfTransparentUnion(QualType Ty) {
192   if (const RecordType *UT = Ty->getAsUnionType()) {
193     const RecordDecl *UD = UT->getDecl();
194     if (UD->hasAttr<TransparentUnionAttr>()) {
195       assert(!UD->field_empty() && "sema created an empty transparent union");
196       return UD->field_begin()->getType();
197     }
198   }
199   return Ty;
200 }
201 
getCXXABI() const202 CGCXXABI &ABIInfo::getCXXABI() const {
203   return CGT.getCXXABI();
204 }
205 
getContext() const206 ASTContext &ABIInfo::getContext() const {
207   return CGT.getContext();
208 }
209 
getVMContext() const210 llvm::LLVMContext &ABIInfo::getVMContext() const {
211   return CGT.getLLVMContext();
212 }
213 
getDataLayout() const214 const llvm::DataLayout &ABIInfo::getDataLayout() const {
215   return CGT.getDataLayout();
216 }
217 
getTarget() const218 const TargetInfo &ABIInfo::getTarget() const {
219   return CGT.getTarget();
220 }
221 
getCodeGenOpts() const222 const CodeGenOptions &ABIInfo::getCodeGenOpts() const {
223   return CGT.getCodeGenOpts();
224 }
225 
isAndroid() const226 bool ABIInfo::isAndroid() const { return getTarget().getTriple().isAndroid(); }
227 
isHomogeneousAggregateBaseType(QualType Ty) const228 bool ABIInfo::isHomogeneousAggregateBaseType(QualType Ty) const {
229   return false;
230 }
231 
isHomogeneousAggregateSmallEnough(const Type * Base,uint64_t Members) const232 bool ABIInfo::isHomogeneousAggregateSmallEnough(const Type *Base,
233                                                 uint64_t Members) const {
234   return false;
235 }
236 
dump() const237 LLVM_DUMP_METHOD void ABIArgInfo::dump() const {
238   raw_ostream &OS = llvm::errs();
239   OS << "(ABIArgInfo Kind=";
240   switch (TheKind) {
241   case Direct:
242     OS << "Direct Type=";
243     if (llvm::Type *Ty = getCoerceToType())
244       Ty->print(OS);
245     else
246       OS << "null";
247     break;
248   case Extend:
249     OS << "Extend";
250     break;
251   case Ignore:
252     OS << "Ignore";
253     break;
254   case InAlloca:
255     OS << "InAlloca Offset=" << getInAllocaFieldIndex();
256     break;
257   case Indirect:
258     OS << "Indirect Align=" << getIndirectAlign().getQuantity()
259        << " ByVal=" << getIndirectByVal()
260        << " Realign=" << getIndirectRealign();
261     break;
262   case IndirectAliased:
263     OS << "Indirect Align=" << getIndirectAlign().getQuantity()
264        << " AadrSpace=" << getIndirectAddrSpace()
265        << " Realign=" << getIndirectRealign();
266     break;
267   case Expand:
268     OS << "Expand";
269     break;
270   case CoerceAndExpand:
271     OS << "CoerceAndExpand Type=";
272     getCoerceAndExpandType()->print(OS);
273     break;
274   }
275   OS << ")\n";
276 }
277 
278 // Dynamically round a pointer up to a multiple of the given alignment.
emitRoundPointerUpToAlignment(CodeGenFunction & CGF,llvm::Value * Ptr,CharUnits Align)279 static llvm::Value *emitRoundPointerUpToAlignment(CodeGenFunction &CGF,
280                                                   llvm::Value *Ptr,
281                                                   CharUnits Align) {
282   llvm::Value *PtrAsInt = Ptr;
283   // OverflowArgArea = (OverflowArgArea + Align - 1) & -Align;
284   PtrAsInt = CGF.Builder.CreatePtrToInt(PtrAsInt, CGF.IntPtrTy);
285   PtrAsInt = CGF.Builder.CreateAdd(PtrAsInt,
286         llvm::ConstantInt::get(CGF.IntPtrTy, Align.getQuantity() - 1));
287   PtrAsInt = CGF.Builder.CreateAnd(PtrAsInt,
288            llvm::ConstantInt::get(CGF.IntPtrTy, -Align.getQuantity()));
289   PtrAsInt = CGF.Builder.CreateIntToPtr(PtrAsInt,
290                                         Ptr->getType(),
291                                         Ptr->getName() + ".aligned");
292   return PtrAsInt;
293 }
294 
295 /// Emit va_arg for a platform using the common void* representation,
296 /// where arguments are simply emitted in an array of slots on the stack.
297 ///
298 /// This version implements the core direct-value passing rules.
299 ///
300 /// \param SlotSize - The size and alignment of a stack slot.
301 ///   Each argument will be allocated to a multiple of this number of
302 ///   slots, and all the slots will be aligned to this value.
303 /// \param AllowHigherAlign - The slot alignment is not a cap;
304 ///   an argument type with an alignment greater than the slot size
305 ///   will be emitted on a higher-alignment address, potentially
306 ///   leaving one or more empty slots behind as padding.  If this
307 ///   is false, the returned address might be less-aligned than
308 ///   DirectAlign.
emitVoidPtrDirectVAArg(CodeGenFunction & CGF,Address VAListAddr,llvm::Type * DirectTy,CharUnits DirectSize,CharUnits DirectAlign,CharUnits SlotSize,bool AllowHigherAlign)309 static Address emitVoidPtrDirectVAArg(CodeGenFunction &CGF,
310                                       Address VAListAddr,
311                                       llvm::Type *DirectTy,
312                                       CharUnits DirectSize,
313                                       CharUnits DirectAlign,
314                                       CharUnits SlotSize,
315                                       bool AllowHigherAlign) {
316   // Cast the element type to i8* if necessary.  Some platforms define
317   // va_list as a struct containing an i8* instead of just an i8*.
318   if (VAListAddr.getElementType() != CGF.Int8PtrTy)
319     VAListAddr = CGF.Builder.CreateElementBitCast(VAListAddr, CGF.Int8PtrTy);
320 
321   llvm::Value *Ptr = CGF.Builder.CreateLoad(VAListAddr, "argp.cur");
322 
323   // If the CC aligns values higher than the slot size, do so if needed.
324   Address Addr = Address::invalid();
325   if (AllowHigherAlign && DirectAlign > SlotSize) {
326     Addr = Address(emitRoundPointerUpToAlignment(CGF, Ptr, DirectAlign),
327                                                  DirectAlign);
328   } else {
329     Addr = Address(Ptr, SlotSize);
330   }
331 
332   // Advance the pointer past the argument, then store that back.
333   CharUnits FullDirectSize = DirectSize.alignTo(SlotSize);
334   Address NextPtr =
335       CGF.Builder.CreateConstInBoundsByteGEP(Addr, FullDirectSize, "argp.next");
336   CGF.Builder.CreateStore(NextPtr.getPointer(), VAListAddr);
337 
338   // If the argument is smaller than a slot, and this is a big-endian
339   // target, the argument will be right-adjusted in its slot.
340   if (DirectSize < SlotSize && CGF.CGM.getDataLayout().isBigEndian() &&
341       !DirectTy->isStructTy()) {
342     Addr = CGF.Builder.CreateConstInBoundsByteGEP(Addr, SlotSize - DirectSize);
343   }
344 
345   Addr = CGF.Builder.CreateElementBitCast(Addr, DirectTy);
346   return Addr;
347 }
348 
349 /// Emit va_arg for a platform using the common void* representation,
350 /// where arguments are simply emitted in an array of slots on the stack.
351 ///
352 /// \param IsIndirect - Values of this type are passed indirectly.
353 /// \param ValueInfo - The size and alignment of this type, generally
354 ///   computed with getContext().getTypeInfoInChars(ValueTy).
355 /// \param SlotSizeAndAlign - The size and alignment of a stack slot.
356 ///   Each argument will be allocated to a multiple of this number of
357 ///   slots, and all the slots will be aligned to this value.
358 /// \param AllowHigherAlign - The slot alignment is not a cap;
359 ///   an argument type with an alignment greater than the slot size
360 ///   will be emitted on a higher-alignment address, potentially
361 ///   leaving one or more empty slots behind as padding.
emitVoidPtrVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType ValueTy,bool IsIndirect,TypeInfoChars ValueInfo,CharUnits SlotSizeAndAlign,bool AllowHigherAlign)362 static Address emitVoidPtrVAArg(CodeGenFunction &CGF, Address VAListAddr,
363                                 QualType ValueTy, bool IsIndirect,
364                                 TypeInfoChars ValueInfo,
365                                 CharUnits SlotSizeAndAlign,
366                                 bool AllowHigherAlign) {
367   // The size and alignment of the value that was passed directly.
368   CharUnits DirectSize, DirectAlign;
369   if (IsIndirect) {
370     DirectSize = CGF.getPointerSize();
371     DirectAlign = CGF.getPointerAlign();
372   } else {
373     DirectSize = ValueInfo.Width;
374     DirectAlign = ValueInfo.Align;
375   }
376 
377   // Cast the address we've calculated to the right type.
378   llvm::Type *DirectTy = CGF.ConvertTypeForMem(ValueTy);
379   if (IsIndirect)
380     DirectTy = DirectTy->getPointerTo(0);
381 
382   Address Addr = emitVoidPtrDirectVAArg(CGF, VAListAddr, DirectTy,
383                                         DirectSize, DirectAlign,
384                                         SlotSizeAndAlign,
385                                         AllowHigherAlign);
386 
387   if (IsIndirect) {
388     Addr = Address(CGF.Builder.CreateLoad(Addr), ValueInfo.Align);
389   }
390 
391   return Addr;
392 
393 }
394 
emitMergePHI(CodeGenFunction & CGF,Address Addr1,llvm::BasicBlock * Block1,Address Addr2,llvm::BasicBlock * Block2,const llvm::Twine & Name="")395 static Address emitMergePHI(CodeGenFunction &CGF,
396                             Address Addr1, llvm::BasicBlock *Block1,
397                             Address Addr2, llvm::BasicBlock *Block2,
398                             const llvm::Twine &Name = "") {
399   assert(Addr1.getType() == Addr2.getType());
400   llvm::PHINode *PHI = CGF.Builder.CreatePHI(Addr1.getType(), 2, Name);
401   PHI->addIncoming(Addr1.getPointer(), Block1);
402   PHI->addIncoming(Addr2.getPointer(), Block2);
403   CharUnits Align = std::min(Addr1.getAlignment(), Addr2.getAlignment());
404   return Address(PHI, Align);
405 }
406 
407 TargetCodeGenInfo::~TargetCodeGenInfo() = default;
408 
409 // If someone can figure out a general rule for this, that would be great.
410 // It's probably just doomed to be platform-dependent, though.
getSizeOfUnwindException() const411 unsigned TargetCodeGenInfo::getSizeOfUnwindException() const {
412   // Verified for:
413   //   x86-64     FreeBSD, Linux, Darwin
414   //   x86-32     FreeBSD, Linux, Darwin
415   //   PowerPC    Linux, Darwin
416   //   ARM        Darwin (*not* EABI)
417   //   AArch64    Linux
418   return 32;
419 }
420 
isNoProtoCallVariadic(const CallArgList & args,const FunctionNoProtoType * fnType) const421 bool TargetCodeGenInfo::isNoProtoCallVariadic(const CallArgList &args,
422                                      const FunctionNoProtoType *fnType) const {
423   // The following conventions are known to require this to be false:
424   //   x86_stdcall
425   //   MIPS
426   // For everything else, we just prefer false unless we opt out.
427   return false;
428 }
429 
430 void
getDependentLibraryOption(llvm::StringRef Lib,llvm::SmallString<24> & Opt) const431 TargetCodeGenInfo::getDependentLibraryOption(llvm::StringRef Lib,
432                                              llvm::SmallString<24> &Opt) const {
433   // This assumes the user is passing a library name like "rt" instead of a
434   // filename like "librt.a/so", and that they don't care whether it's static or
435   // dynamic.
436   Opt = "-l";
437   Opt += Lib;
438 }
439 
getOpenCLKernelCallingConv() const440 unsigned TargetCodeGenInfo::getOpenCLKernelCallingConv() const {
441   // OpenCL kernels are called via an explicit runtime API with arguments
442   // set with clSetKernelArg(), not as normal sub-functions.
443   // Return SPIR_KERNEL by default as the kernel calling convention to
444   // ensure the fingerprint is fixed such way that each OpenCL argument
445   // gets one matching argument in the produced kernel function argument
446   // list to enable feasible implementation of clSetKernelArg() with
447   // aggregates etc. In case we would use the default C calling conv here,
448   // clSetKernelArg() might break depending on the target-specific
449   // conventions; different targets might split structs passed as values
450   // to multiple function arguments etc.
451   return llvm::CallingConv::SPIR_KERNEL;
452 }
453 
getNullPointer(const CodeGen::CodeGenModule & CGM,llvm::PointerType * T,QualType QT) const454 llvm::Constant *TargetCodeGenInfo::getNullPointer(const CodeGen::CodeGenModule &CGM,
455     llvm::PointerType *T, QualType QT) const {
456   return llvm::ConstantPointerNull::get(T);
457 }
458 
getGlobalVarAddressSpace(CodeGenModule & CGM,const VarDecl * D) const459 LangAS TargetCodeGenInfo::getGlobalVarAddressSpace(CodeGenModule &CGM,
460                                                    const VarDecl *D) const {
461   assert(!CGM.getLangOpts().OpenCL &&
462          !(CGM.getLangOpts().CUDA && CGM.getLangOpts().CUDAIsDevice) &&
463          "Address space agnostic languages only");
464   return D ? D->getType().getAddressSpace() : LangAS::Default;
465 }
466 
performAddrSpaceCast(CodeGen::CodeGenFunction & CGF,llvm::Value * Src,LangAS SrcAddr,LangAS DestAddr,llvm::Type * DestTy,bool isNonNull) const467 llvm::Value *TargetCodeGenInfo::performAddrSpaceCast(
468     CodeGen::CodeGenFunction &CGF, llvm::Value *Src, LangAS SrcAddr,
469     LangAS DestAddr, llvm::Type *DestTy, bool isNonNull) const {
470   // Since target may map different address spaces in AST to the same address
471   // space, an address space conversion may end up as a bitcast.
472   if (auto *C = dyn_cast<llvm::Constant>(Src))
473     return performAddrSpaceCast(CGF.CGM, C, SrcAddr, DestAddr, DestTy);
474   // Try to preserve the source's name to make IR more readable.
475   return CGF.Builder.CreatePointerBitCastOrAddrSpaceCast(
476       Src, DestTy, Src->hasName() ? Src->getName() + ".ascast" : "");
477 }
478 
479 llvm::Constant *
performAddrSpaceCast(CodeGenModule & CGM,llvm::Constant * Src,LangAS SrcAddr,LangAS DestAddr,llvm::Type * DestTy) const480 TargetCodeGenInfo::performAddrSpaceCast(CodeGenModule &CGM, llvm::Constant *Src,
481                                         LangAS SrcAddr, LangAS DestAddr,
482                                         llvm::Type *DestTy) const {
483   // Since target may map different address spaces in AST to the same address
484   // space, an address space conversion may end up as a bitcast.
485   return llvm::ConstantExpr::getPointerCast(Src, DestTy);
486 }
487 
488 llvm::SyncScope::ID
getLLVMSyncScopeID(const LangOptions & LangOpts,SyncScope Scope,llvm::AtomicOrdering Ordering,llvm::LLVMContext & Ctx) const489 TargetCodeGenInfo::getLLVMSyncScopeID(const LangOptions &LangOpts,
490                                       SyncScope Scope,
491                                       llvm::AtomicOrdering Ordering,
492                                       llvm::LLVMContext &Ctx) const {
493   return Ctx.getOrInsertSyncScopeID(""); /* default sync scope */
494 }
495 
496 static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays);
497 
498 /// isEmptyField - Return true iff a the field is "empty", that is it
499 /// is an unnamed bit-field or an (array of) empty record(s).
isEmptyField(ASTContext & Context,const FieldDecl * FD,bool AllowArrays)500 static bool isEmptyField(ASTContext &Context, const FieldDecl *FD,
501                          bool AllowArrays) {
502   if (FD->isUnnamedBitfield())
503     return true;
504 
505   QualType FT = FD->getType();
506 
507   // Constant arrays of empty records count as empty, strip them off.
508   // Constant arrays of zero length always count as empty.
509   bool WasArray = false;
510   if (AllowArrays)
511     while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
512       if (AT->getSize() == 0)
513         return true;
514       FT = AT->getElementType();
515       // The [[no_unique_address]] special case below does not apply to
516       // arrays of C++ empty records, so we need to remember this fact.
517       WasArray = true;
518     }
519 
520   const RecordType *RT = FT->getAs<RecordType>();
521   if (!RT)
522     return false;
523 
524   // C++ record fields are never empty, at least in the Itanium ABI.
525   //
526   // FIXME: We should use a predicate for whether this behavior is true in the
527   // current ABI.
528   //
529   // The exception to the above rule are fields marked with the
530   // [[no_unique_address]] attribute (since C++20).  Those do count as empty
531   // according to the Itanium ABI.  The exception applies only to records,
532   // not arrays of records, so we must also check whether we stripped off an
533   // array type above.
534   if (isa<CXXRecordDecl>(RT->getDecl()) &&
535       (WasArray || !FD->hasAttr<NoUniqueAddressAttr>()))
536     return false;
537 
538   return isEmptyRecord(Context, FT, AllowArrays);
539 }
540 
541 /// isEmptyRecord - Return true iff a structure contains only empty
542 /// fields. Note that a structure with a flexible array member is not
543 /// considered empty.
isEmptyRecord(ASTContext & Context,QualType T,bool AllowArrays)544 static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays) {
545   const RecordType *RT = T->getAs<RecordType>();
546   if (!RT)
547     return false;
548   const RecordDecl *RD = RT->getDecl();
549   if (RD->hasFlexibleArrayMember())
550     return false;
551 
552   // If this is a C++ record, check the bases first.
553   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
554     for (const auto &I : CXXRD->bases())
555       if (!isEmptyRecord(Context, I.getType(), true))
556         return false;
557 
558   for (const auto *I : RD->fields())
559     if (!isEmptyField(Context, I, AllowArrays))
560       return false;
561   return true;
562 }
563 
564 /// isSingleElementStruct - Determine if a structure is a "single
565 /// element struct", i.e. it has exactly one non-empty field or
566 /// exactly one field which is itself a single element
567 /// struct. Structures with flexible array members are never
568 /// considered single element structs.
569 ///
570 /// \return The field declaration for the single non-empty field, if
571 /// it exists.
isSingleElementStruct(QualType T,ASTContext & Context)572 static const Type *isSingleElementStruct(QualType T, ASTContext &Context) {
573   const RecordType *RT = T->getAs<RecordType>();
574   if (!RT)
575     return nullptr;
576 
577   const RecordDecl *RD = RT->getDecl();
578   if (RD->hasFlexibleArrayMember())
579     return nullptr;
580 
581   const Type *Found = nullptr;
582 
583   // If this is a C++ record, check the bases first.
584   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
585     for (const auto &I : CXXRD->bases()) {
586       // Ignore empty records.
587       if (isEmptyRecord(Context, I.getType(), true))
588         continue;
589 
590       // If we already found an element then this isn't a single-element struct.
591       if (Found)
592         return nullptr;
593 
594       // If this is non-empty and not a single element struct, the composite
595       // cannot be a single element struct.
596       Found = isSingleElementStruct(I.getType(), Context);
597       if (!Found)
598         return nullptr;
599     }
600   }
601 
602   // Check for single element.
603   for (const auto *FD : RD->fields()) {
604     QualType FT = FD->getType();
605 
606     // Ignore empty fields.
607     if (isEmptyField(Context, FD, true))
608       continue;
609 
610     // If we already found an element then this isn't a single-element
611     // struct.
612     if (Found)
613       return nullptr;
614 
615     // Treat single element arrays as the element.
616     while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
617       if (AT->getSize().getZExtValue() != 1)
618         break;
619       FT = AT->getElementType();
620     }
621 
622     if (!isAggregateTypeForABI(FT)) {
623       Found = FT.getTypePtr();
624     } else {
625       Found = isSingleElementStruct(FT, Context);
626       if (!Found)
627         return nullptr;
628     }
629   }
630 
631   // We don't consider a struct a single-element struct if it has
632   // padding beyond the element type.
633   if (Found && Context.getTypeSize(Found) != Context.getTypeSize(T))
634     return nullptr;
635 
636   return Found;
637 }
638 
639 namespace {
EmitVAArgInstr(CodeGenFunction & CGF,Address VAListAddr,QualType Ty,const ABIArgInfo & AI)640 Address EmitVAArgInstr(CodeGenFunction &CGF, Address VAListAddr, QualType Ty,
641                        const ABIArgInfo &AI) {
642   // This default implementation defers to the llvm backend's va_arg
643   // instruction. It can handle only passing arguments directly
644   // (typically only handled in the backend for primitive types), or
645   // aggregates passed indirectly by pointer (NOTE: if the "byval"
646   // flag has ABI impact in the callee, this implementation cannot
647   // work.)
648 
649   // Only a few cases are covered here at the moment -- those needed
650   // by the default abi.
651   llvm::Value *Val;
652 
653   if (AI.isIndirect()) {
654     assert(!AI.getPaddingType() &&
655            "Unexpected PaddingType seen in arginfo in generic VAArg emitter!");
656     assert(
657         !AI.getIndirectRealign() &&
658         "Unexpected IndirectRealign seen in arginfo in generic VAArg emitter!");
659 
660     auto TyInfo = CGF.getContext().getTypeInfoInChars(Ty);
661     CharUnits TyAlignForABI = TyInfo.Align;
662 
663     llvm::Type *BaseTy =
664         llvm::PointerType::getUnqual(CGF.ConvertTypeForMem(Ty));
665     llvm::Value *Addr =
666         CGF.Builder.CreateVAArg(VAListAddr.getPointer(), BaseTy);
667     return Address(Addr, TyAlignForABI);
668   } else {
669     assert((AI.isDirect() || AI.isExtend()) &&
670            "Unexpected ArgInfo Kind in generic VAArg emitter!");
671 
672     assert(!AI.getInReg() &&
673            "Unexpected InReg seen in arginfo in generic VAArg emitter!");
674     assert(!AI.getPaddingType() &&
675            "Unexpected PaddingType seen in arginfo in generic VAArg emitter!");
676     assert(!AI.getDirectOffset() &&
677            "Unexpected DirectOffset seen in arginfo in generic VAArg emitter!");
678     assert(!AI.getCoerceToType() &&
679            "Unexpected CoerceToType seen in arginfo in generic VAArg emitter!");
680 
681     Address Temp = CGF.CreateMemTemp(Ty, "varet");
682     Val = CGF.Builder.CreateVAArg(VAListAddr.getPointer(), CGF.ConvertType(Ty));
683     CGF.Builder.CreateStore(Val, Temp);
684     return Temp;
685   }
686 }
687 
688 /// DefaultABIInfo - The default implementation for ABI specific
689 /// details. This implementation provides information which results in
690 /// self-consistent and sensible LLVM IR generation, but does not
691 /// conform to any particular ABI.
692 class DefaultABIInfo : public ABIInfo {
693 public:
DefaultABIInfo(CodeGen::CodeGenTypes & CGT)694   DefaultABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
695 
696   ABIArgInfo classifyReturnType(QualType RetTy) const;
697   ABIArgInfo classifyArgumentType(QualType RetTy) const;
698 
computeInfo(CGFunctionInfo & FI) const699   void computeInfo(CGFunctionInfo &FI) const override {
700     if (!getCXXABI().classifyReturnType(FI))
701       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
702     for (auto &I : FI.arguments())
703       I.info = classifyArgumentType(I.type);
704   }
705 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const706   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
707                     QualType Ty) const override {
708     return EmitVAArgInstr(CGF, VAListAddr, Ty, classifyArgumentType(Ty));
709   }
710 };
711 
712 class DefaultTargetCodeGenInfo : public TargetCodeGenInfo {
713 public:
DefaultTargetCodeGenInfo(CodeGen::CodeGenTypes & CGT)714   DefaultTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
715       : TargetCodeGenInfo(std::make_unique<DefaultABIInfo>(CGT)) {}
716 };
717 
classifyArgumentType(QualType Ty) const718 ABIArgInfo DefaultABIInfo::classifyArgumentType(QualType Ty) const {
719   Ty = useFirstFieldIfTransparentUnion(Ty);
720 
721   if (isAggregateTypeForABI(Ty)) {
722     // Records with non-trivial destructors/copy-constructors should not be
723     // passed by value.
724     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
725       return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
726 
727     return getNaturalAlignIndirect(Ty);
728   }
729 
730   // Treat an enum type as its underlying type.
731   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
732     Ty = EnumTy->getDecl()->getIntegerType();
733 
734   ASTContext &Context = getContext();
735   if (const auto *EIT = Ty->getAs<ExtIntType>())
736     if (EIT->getNumBits() >
737         Context.getTypeSize(Context.getTargetInfo().hasInt128Type()
738                                 ? Context.Int128Ty
739                                 : Context.LongLongTy))
740       return getNaturalAlignIndirect(Ty);
741 
742   return (isPromotableIntegerTypeForABI(Ty) ? ABIArgInfo::getExtend(Ty)
743                                             : ABIArgInfo::getDirect());
744 }
745 
classifyReturnType(QualType RetTy) const746 ABIArgInfo DefaultABIInfo::classifyReturnType(QualType RetTy) const {
747   if (RetTy->isVoidType())
748     return ABIArgInfo::getIgnore();
749 
750   if (isAggregateTypeForABI(RetTy))
751     return getNaturalAlignIndirect(RetTy);
752 
753   // Treat an enum type as its underlying type.
754   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
755     RetTy = EnumTy->getDecl()->getIntegerType();
756 
757   if (const auto *EIT = RetTy->getAs<ExtIntType>())
758     if (EIT->getNumBits() >
759         getContext().getTypeSize(getContext().getTargetInfo().hasInt128Type()
760                                      ? getContext().Int128Ty
761                                      : getContext().LongLongTy))
762       return getNaturalAlignIndirect(RetTy);
763 
764   return (isPromotableIntegerTypeForABI(RetTy) ? ABIArgInfo::getExtend(RetTy)
765                                                : ABIArgInfo::getDirect());
766 }
767 
768 //===----------------------------------------------------------------------===//
769 // WebAssembly ABI Implementation
770 //
771 // This is a very simple ABI that relies a lot on DefaultABIInfo.
772 //===----------------------------------------------------------------------===//
773 
774 class WebAssemblyABIInfo final : public SwiftABIInfo {
775 public:
776   enum ABIKind {
777     MVP = 0,
778     ExperimentalMV = 1,
779   };
780 
781 private:
782   DefaultABIInfo defaultInfo;
783   ABIKind Kind;
784 
785 public:
WebAssemblyABIInfo(CodeGen::CodeGenTypes & CGT,ABIKind Kind)786   explicit WebAssemblyABIInfo(CodeGen::CodeGenTypes &CGT, ABIKind Kind)
787       : SwiftABIInfo(CGT), defaultInfo(CGT), Kind(Kind) {}
788 
789 private:
790   ABIArgInfo classifyReturnType(QualType RetTy) const;
791   ABIArgInfo classifyArgumentType(QualType Ty) const;
792 
793   // DefaultABIInfo's classifyReturnType and classifyArgumentType are
794   // non-virtual, but computeInfo and EmitVAArg are virtual, so we
795   // overload them.
computeInfo(CGFunctionInfo & FI) const796   void computeInfo(CGFunctionInfo &FI) const override {
797     if (!getCXXABI().classifyReturnType(FI))
798       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
799     for (auto &Arg : FI.arguments())
800       Arg.info = classifyArgumentType(Arg.type);
801   }
802 
803   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
804                     QualType Ty) const override;
805 
shouldPassIndirectlyForSwift(ArrayRef<llvm::Type * > scalars,bool asReturnValue) const806   bool shouldPassIndirectlyForSwift(ArrayRef<llvm::Type*> scalars,
807                                     bool asReturnValue) const override {
808     return occupiesMoreThan(CGT, scalars, /*total*/ 4);
809   }
810 
isSwiftErrorInRegister() const811   bool isSwiftErrorInRegister() const override {
812     return false;
813   }
814 };
815 
816 class WebAssemblyTargetCodeGenInfo final : public TargetCodeGenInfo {
817 public:
WebAssemblyTargetCodeGenInfo(CodeGen::CodeGenTypes & CGT,WebAssemblyABIInfo::ABIKind K)818   explicit WebAssemblyTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
819                                         WebAssemblyABIInfo::ABIKind K)
820       : TargetCodeGenInfo(std::make_unique<WebAssemblyABIInfo>(CGT, K)) {}
821 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & CGM) const822   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
823                            CodeGen::CodeGenModule &CGM) const override {
824     TargetCodeGenInfo::setTargetAttributes(D, GV, CGM);
825     if (const auto *FD = dyn_cast_or_null<FunctionDecl>(D)) {
826       if (const auto *Attr = FD->getAttr<WebAssemblyImportModuleAttr>()) {
827         llvm::Function *Fn = cast<llvm::Function>(GV);
828         llvm::AttrBuilder B;
829         B.addAttribute("wasm-import-module", Attr->getImportModule());
830         Fn->addAttributes(llvm::AttributeList::FunctionIndex, B);
831       }
832       if (const auto *Attr = FD->getAttr<WebAssemblyImportNameAttr>()) {
833         llvm::Function *Fn = cast<llvm::Function>(GV);
834         llvm::AttrBuilder B;
835         B.addAttribute("wasm-import-name", Attr->getImportName());
836         Fn->addAttributes(llvm::AttributeList::FunctionIndex, B);
837       }
838       if (const auto *Attr = FD->getAttr<WebAssemblyExportNameAttr>()) {
839         llvm::Function *Fn = cast<llvm::Function>(GV);
840         llvm::AttrBuilder B;
841         B.addAttribute("wasm-export-name", Attr->getExportName());
842         Fn->addAttributes(llvm::AttributeList::FunctionIndex, B);
843       }
844     }
845 
846     if (auto *FD = dyn_cast_or_null<FunctionDecl>(D)) {
847       llvm::Function *Fn = cast<llvm::Function>(GV);
848       if (!FD->doesThisDeclarationHaveABody() && !FD->hasPrototype())
849         Fn->addFnAttr("no-prototype");
850     }
851   }
852 };
853 
854 /// Classify argument of given type \p Ty.
classifyArgumentType(QualType Ty) const855 ABIArgInfo WebAssemblyABIInfo::classifyArgumentType(QualType Ty) const {
856   Ty = useFirstFieldIfTransparentUnion(Ty);
857 
858   if (isAggregateTypeForABI(Ty)) {
859     // Records with non-trivial destructors/copy-constructors should not be
860     // passed by value.
861     if (auto RAA = getRecordArgABI(Ty, getCXXABI()))
862       return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
863     // Ignore empty structs/unions.
864     if (isEmptyRecord(getContext(), Ty, true))
865       return ABIArgInfo::getIgnore();
866     // Lower single-element structs to just pass a regular value. TODO: We
867     // could do reasonable-size multiple-element structs too, using getExpand(),
868     // though watch out for things like bitfields.
869     if (const Type *SeltTy = isSingleElementStruct(Ty, getContext()))
870       return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
871     // For the experimental multivalue ABI, fully expand all other aggregates
872     if (Kind == ABIKind::ExperimentalMV) {
873       const RecordType *RT = Ty->getAs<RecordType>();
874       assert(RT);
875       bool HasBitField = false;
876       for (auto *Field : RT->getDecl()->fields()) {
877         if (Field->isBitField()) {
878           HasBitField = true;
879           break;
880         }
881       }
882       if (!HasBitField)
883         return ABIArgInfo::getExpand();
884     }
885   }
886 
887   // Otherwise just do the default thing.
888   return defaultInfo.classifyArgumentType(Ty);
889 }
890 
classifyReturnType(QualType RetTy) const891 ABIArgInfo WebAssemblyABIInfo::classifyReturnType(QualType RetTy) const {
892   if (isAggregateTypeForABI(RetTy)) {
893     // Records with non-trivial destructors/copy-constructors should not be
894     // returned by value.
895     if (!getRecordArgABI(RetTy, getCXXABI())) {
896       // Ignore empty structs/unions.
897       if (isEmptyRecord(getContext(), RetTy, true))
898         return ABIArgInfo::getIgnore();
899       // Lower single-element structs to just return a regular value. TODO: We
900       // could do reasonable-size multiple-element structs too, using
901       // ABIArgInfo::getDirect().
902       if (const Type *SeltTy = isSingleElementStruct(RetTy, getContext()))
903         return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
904       // For the experimental multivalue ABI, return all other aggregates
905       if (Kind == ABIKind::ExperimentalMV)
906         return ABIArgInfo::getDirect();
907     }
908   }
909 
910   // Otherwise just do the default thing.
911   return defaultInfo.classifyReturnType(RetTy);
912 }
913 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const914 Address WebAssemblyABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
915                                       QualType Ty) const {
916   bool IsIndirect = isAggregateTypeForABI(Ty) &&
917                     !isEmptyRecord(getContext(), Ty, true) &&
918                     !isSingleElementStruct(Ty, getContext());
919   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, IsIndirect,
920                           getContext().getTypeInfoInChars(Ty),
921                           CharUnits::fromQuantity(4),
922                           /*AllowHigherAlign=*/true);
923 }
924 
925 //===----------------------------------------------------------------------===//
926 // le32/PNaCl bitcode ABI Implementation
927 //
928 // This is a simplified version of the x86_32 ABI.  Arguments and return values
929 // are always passed on the stack.
930 //===----------------------------------------------------------------------===//
931 
932 class PNaClABIInfo : public ABIInfo {
933  public:
PNaClABIInfo(CodeGen::CodeGenTypes & CGT)934   PNaClABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
935 
936   ABIArgInfo classifyReturnType(QualType RetTy) const;
937   ABIArgInfo classifyArgumentType(QualType RetTy) const;
938 
939   void computeInfo(CGFunctionInfo &FI) const override;
940   Address EmitVAArg(CodeGenFunction &CGF,
941                     Address VAListAddr, QualType Ty) const override;
942 };
943 
944 class PNaClTargetCodeGenInfo : public TargetCodeGenInfo {
945  public:
PNaClTargetCodeGenInfo(CodeGen::CodeGenTypes & CGT)946    PNaClTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
947        : TargetCodeGenInfo(std::make_unique<PNaClABIInfo>(CGT)) {}
948 };
949 
computeInfo(CGFunctionInfo & FI) const950 void PNaClABIInfo::computeInfo(CGFunctionInfo &FI) const {
951   if (!getCXXABI().classifyReturnType(FI))
952     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
953 
954   for (auto &I : FI.arguments())
955     I.info = classifyArgumentType(I.type);
956 }
957 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const958 Address PNaClABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
959                                 QualType Ty) const {
960   // The PNaCL ABI is a bit odd, in that varargs don't use normal
961   // function classification. Structs get passed directly for varargs
962   // functions, through a rewriting transform in
963   // pnacl-llvm/lib/Transforms/NaCl/ExpandVarArgs.cpp, which allows
964   // this target to actually support a va_arg instructions with an
965   // aggregate type, unlike other targets.
966   return EmitVAArgInstr(CGF, VAListAddr, Ty, ABIArgInfo::getDirect());
967 }
968 
969 /// Classify argument of given type \p Ty.
classifyArgumentType(QualType Ty) const970 ABIArgInfo PNaClABIInfo::classifyArgumentType(QualType Ty) const {
971   if (isAggregateTypeForABI(Ty)) {
972     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
973       return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
974     return getNaturalAlignIndirect(Ty);
975   } else if (const EnumType *EnumTy = Ty->getAs<EnumType>()) {
976     // Treat an enum type as its underlying type.
977     Ty = EnumTy->getDecl()->getIntegerType();
978   } else if (Ty->isFloatingType()) {
979     // Floating-point types don't go inreg.
980     return ABIArgInfo::getDirect();
981   } else if (const auto *EIT = Ty->getAs<ExtIntType>()) {
982     // Treat extended integers as integers if <=64, otherwise pass indirectly.
983     if (EIT->getNumBits() > 64)
984       return getNaturalAlignIndirect(Ty);
985     return ABIArgInfo::getDirect();
986   }
987 
988   return (isPromotableIntegerTypeForABI(Ty) ? ABIArgInfo::getExtend(Ty)
989                                             : ABIArgInfo::getDirect());
990 }
991 
classifyReturnType(QualType RetTy) const992 ABIArgInfo PNaClABIInfo::classifyReturnType(QualType RetTy) const {
993   if (RetTy->isVoidType())
994     return ABIArgInfo::getIgnore();
995 
996   // In the PNaCl ABI we always return records/structures on the stack.
997   if (isAggregateTypeForABI(RetTy))
998     return getNaturalAlignIndirect(RetTy);
999 
1000   // Treat extended integers as integers if <=64, otherwise pass indirectly.
1001   if (const auto *EIT = RetTy->getAs<ExtIntType>()) {
1002     if (EIT->getNumBits() > 64)
1003       return getNaturalAlignIndirect(RetTy);
1004     return ABIArgInfo::getDirect();
1005   }
1006 
1007   // Treat an enum type as its underlying type.
1008   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
1009     RetTy = EnumTy->getDecl()->getIntegerType();
1010 
1011   return (isPromotableIntegerTypeForABI(RetTy) ? ABIArgInfo::getExtend(RetTy)
1012                                                : ABIArgInfo::getDirect());
1013 }
1014 
1015 /// IsX86_MMXType - Return true if this is an MMX type.
IsX86_MMXType(llvm::Type * IRType)1016 bool IsX86_MMXType(llvm::Type *IRType) {
1017   // Return true if the type is an MMX type <2 x i32>, <4 x i16>, or <8 x i8>.
1018   return IRType->isVectorTy() && IRType->getPrimitiveSizeInBits() == 64 &&
1019     cast<llvm::VectorType>(IRType)->getElementType()->isIntegerTy() &&
1020     IRType->getScalarSizeInBits() != 64;
1021 }
1022 
X86AdjustInlineAsmType(CodeGen::CodeGenFunction & CGF,StringRef Constraint,llvm::Type * Ty)1023 static llvm::Type* X86AdjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
1024                                           StringRef Constraint,
1025                                           llvm::Type* Ty) {
1026   bool IsMMXCons = llvm::StringSwitch<bool>(Constraint)
1027                      .Cases("y", "&y", "^Ym", true)
1028                      .Default(false);
1029   if (IsMMXCons && Ty->isVectorTy()) {
1030     if (cast<llvm::VectorType>(Ty)->getPrimitiveSizeInBits().getFixedSize() !=
1031         64) {
1032       // Invalid MMX constraint
1033       return nullptr;
1034     }
1035 
1036     return llvm::Type::getX86_MMXTy(CGF.getLLVMContext());
1037   }
1038 
1039   // No operation needed
1040   return Ty;
1041 }
1042 
1043 /// Returns true if this type can be passed in SSE registers with the
1044 /// X86_VectorCall calling convention. Shared between x86_32 and x86_64.
isX86VectorTypeForVectorCall(ASTContext & Context,QualType Ty)1045 static bool isX86VectorTypeForVectorCall(ASTContext &Context, QualType Ty) {
1046   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
1047     if (BT->isFloatingPoint() && BT->getKind() != BuiltinType::Half) {
1048       if (BT->getKind() == BuiltinType::LongDouble) {
1049         if (&Context.getTargetInfo().getLongDoubleFormat() ==
1050             &llvm::APFloat::x87DoubleExtended())
1051           return false;
1052       }
1053       return true;
1054     }
1055   } else if (const VectorType *VT = Ty->getAs<VectorType>()) {
1056     // vectorcall can pass XMM, YMM, and ZMM vectors. We don't pass SSE1 MMX
1057     // registers specially.
1058     unsigned VecSize = Context.getTypeSize(VT);
1059     if (VecSize == 128 || VecSize == 256 || VecSize == 512)
1060       return true;
1061   }
1062   return false;
1063 }
1064 
1065 /// Returns true if this aggregate is small enough to be passed in SSE registers
1066 /// in the X86_VectorCall calling convention. Shared between x86_32 and x86_64.
isX86VectorCallAggregateSmallEnough(uint64_t NumMembers)1067 static bool isX86VectorCallAggregateSmallEnough(uint64_t NumMembers) {
1068   return NumMembers <= 4;
1069 }
1070 
1071 /// Returns a Homogeneous Vector Aggregate ABIArgInfo, used in X86.
getDirectX86Hva(llvm::Type * T=nullptr)1072 static ABIArgInfo getDirectX86Hva(llvm::Type* T = nullptr) {
1073   auto AI = ABIArgInfo::getDirect(T);
1074   AI.setInReg(true);
1075   AI.setCanBeFlattened(false);
1076   return AI;
1077 }
1078 
1079 //===----------------------------------------------------------------------===//
1080 // X86-32 ABI Implementation
1081 //===----------------------------------------------------------------------===//
1082 
1083 /// Similar to llvm::CCState, but for Clang.
1084 struct CCState {
CCState__anon666ee6d70111::CCState1085   CCState(CGFunctionInfo &FI)
1086       : IsPreassigned(FI.arg_size()), CC(FI.getCallingConvention()) {}
1087 
1088   llvm::SmallBitVector IsPreassigned;
1089   unsigned CC = CallingConv::CC_C;
1090   unsigned FreeRegs = 0;
1091   unsigned FreeSSERegs = 0;
1092 };
1093 
1094 /// X86_32ABIInfo - The X86-32 ABI information.
1095 class X86_32ABIInfo : public SwiftABIInfo {
1096   enum Class {
1097     Integer,
1098     Float
1099   };
1100 
1101   static const unsigned MinABIStackAlignInBytes = 4;
1102 
1103   bool IsDarwinVectorABI;
1104   bool IsRetSmallStructInRegABI;
1105   bool IsWin32StructABI;
1106   bool IsSoftFloatABI;
1107   bool IsMCUABI;
1108   bool IsLinuxABI;
1109   unsigned DefaultNumRegisterParameters;
1110 
isRegisterSize(unsigned Size)1111   static bool isRegisterSize(unsigned Size) {
1112     return (Size == 8 || Size == 16 || Size == 32 || Size == 64);
1113   }
1114 
isHomogeneousAggregateBaseType(QualType Ty) const1115   bool isHomogeneousAggregateBaseType(QualType Ty) const override {
1116     // FIXME: Assumes vectorcall is in use.
1117     return isX86VectorTypeForVectorCall(getContext(), Ty);
1118   }
1119 
isHomogeneousAggregateSmallEnough(const Type * Ty,uint64_t NumMembers) const1120   bool isHomogeneousAggregateSmallEnough(const Type *Ty,
1121                                          uint64_t NumMembers) const override {
1122     // FIXME: Assumes vectorcall is in use.
1123     return isX86VectorCallAggregateSmallEnough(NumMembers);
1124   }
1125 
1126   bool shouldReturnTypeInRegister(QualType Ty, ASTContext &Context) const;
1127 
1128   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
1129   /// such that the argument will be passed in memory.
1130   ABIArgInfo getIndirectResult(QualType Ty, bool ByVal, CCState &State) const;
1131 
1132   ABIArgInfo getIndirectReturnResult(QualType Ty, CCState &State) const;
1133 
1134   /// Return the alignment to use for the given type on the stack.
1135   unsigned getTypeStackAlignInBytes(QualType Ty, unsigned Align) const;
1136 
1137   Class classify(QualType Ty) const;
1138   ABIArgInfo classifyReturnType(QualType RetTy, CCState &State) const;
1139   ABIArgInfo classifyArgumentType(QualType RetTy, CCState &State) const;
1140 
1141   /// Updates the number of available free registers, returns
1142   /// true if any registers were allocated.
1143   bool updateFreeRegs(QualType Ty, CCState &State) const;
1144 
1145   bool shouldAggregateUseDirect(QualType Ty, CCState &State, bool &InReg,
1146                                 bool &NeedsPadding) const;
1147   bool shouldPrimitiveUseInReg(QualType Ty, CCState &State) const;
1148 
1149   bool canExpandIndirectArgument(QualType Ty) const;
1150 
1151   /// Rewrite the function info so that all memory arguments use
1152   /// inalloca.
1153   void rewriteWithInAlloca(CGFunctionInfo &FI) const;
1154 
1155   void addFieldToArgStruct(SmallVector<llvm::Type *, 6> &FrameFields,
1156                            CharUnits &StackOffset, ABIArgInfo &Info,
1157                            QualType Type) const;
1158   void runVectorCallFirstPass(CGFunctionInfo &FI, CCState &State) const;
1159 
1160 public:
1161 
1162   void computeInfo(CGFunctionInfo &FI) const override;
1163   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
1164                     QualType Ty) const override;
1165 
X86_32ABIInfo(CodeGen::CodeGenTypes & CGT,bool DarwinVectorABI,bool RetSmallStructInRegABI,bool Win32StructABI,unsigned NumRegisterParameters,bool SoftFloatABI)1166   X86_32ABIInfo(CodeGen::CodeGenTypes &CGT, bool DarwinVectorABI,
1167                 bool RetSmallStructInRegABI, bool Win32StructABI,
1168                 unsigned NumRegisterParameters, bool SoftFloatABI)
1169     : SwiftABIInfo(CGT), IsDarwinVectorABI(DarwinVectorABI),
1170       IsRetSmallStructInRegABI(RetSmallStructInRegABI),
1171       IsWin32StructABI(Win32StructABI), IsSoftFloatABI(SoftFloatABI),
1172       IsMCUABI(CGT.getTarget().getTriple().isOSIAMCU()),
1173       IsLinuxABI(CGT.getTarget().getTriple().isOSLinux()),
1174       DefaultNumRegisterParameters(NumRegisterParameters) {}
1175 
shouldPassIndirectlyForSwift(ArrayRef<llvm::Type * > scalars,bool asReturnValue) const1176   bool shouldPassIndirectlyForSwift(ArrayRef<llvm::Type*> scalars,
1177                                     bool asReturnValue) const override {
1178     // LLVM's x86-32 lowering currently only assigns up to three
1179     // integer registers and three fp registers.  Oddly, it'll use up to
1180     // four vector registers for vectors, but those can overlap with the
1181     // scalar registers.
1182     return occupiesMoreThan(CGT, scalars, /*total*/ 3);
1183   }
1184 
isSwiftErrorInRegister() const1185   bool isSwiftErrorInRegister() const override {
1186     // x86-32 lowering does not support passing swifterror in a register.
1187     return false;
1188   }
1189 };
1190 
1191 class X86_32TargetCodeGenInfo : public TargetCodeGenInfo {
1192 public:
X86_32TargetCodeGenInfo(CodeGen::CodeGenTypes & CGT,bool DarwinVectorABI,bool RetSmallStructInRegABI,bool Win32StructABI,unsigned NumRegisterParameters,bool SoftFloatABI)1193   X86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool DarwinVectorABI,
1194                           bool RetSmallStructInRegABI, bool Win32StructABI,
1195                           unsigned NumRegisterParameters, bool SoftFloatABI)
1196       : TargetCodeGenInfo(std::make_unique<X86_32ABIInfo>(
1197             CGT, DarwinVectorABI, RetSmallStructInRegABI, Win32StructABI,
1198             NumRegisterParameters, SoftFloatABI)) {}
1199 
1200   static bool isStructReturnInRegABI(
1201       const llvm::Triple &Triple, const CodeGenOptions &Opts);
1202 
1203   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
1204                            CodeGen::CodeGenModule &CGM) const override;
1205 
getDwarfEHStackPointer(CodeGen::CodeGenModule & CGM) const1206   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
1207     // Darwin uses different dwarf register numbers for EH.
1208     if (CGM.getTarget().getTriple().isOSDarwin()) return 5;
1209     return 4;
1210   }
1211 
1212   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
1213                                llvm::Value *Address) const override;
1214 
adjustInlineAsmType(CodeGen::CodeGenFunction & CGF,StringRef Constraint,llvm::Type * Ty) const1215   llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
1216                                   StringRef Constraint,
1217                                   llvm::Type* Ty) const override {
1218     return X86AdjustInlineAsmType(CGF, Constraint, Ty);
1219   }
1220 
1221   void addReturnRegisterOutputs(CodeGenFunction &CGF, LValue ReturnValue,
1222                                 std::string &Constraints,
1223                                 std::vector<llvm::Type *> &ResultRegTypes,
1224                                 std::vector<llvm::Type *> &ResultTruncRegTypes,
1225                                 std::vector<LValue> &ResultRegDests,
1226                                 std::string &AsmString,
1227                                 unsigned NumOutputs) const override;
1228 
1229   llvm::Constant *
getUBSanFunctionSignature(CodeGen::CodeGenModule & CGM) const1230   getUBSanFunctionSignature(CodeGen::CodeGenModule &CGM) const override {
1231     unsigned Sig = (0xeb << 0) |  // jmp rel8
1232                    (0x06 << 8) |  //           .+0x08
1233                    ('v' << 16) |
1234                    ('2' << 24);
1235     return llvm::ConstantInt::get(CGM.Int32Ty, Sig);
1236   }
1237 
getARCRetainAutoreleasedReturnValueMarker() const1238   StringRef getARCRetainAutoreleasedReturnValueMarker() const override {
1239     return "movl\t%ebp, %ebp"
1240            "\t\t// marker for objc_retainAutoreleaseReturnValue";
1241   }
1242 };
1243 
1244 }
1245 
1246 /// Rewrite input constraint references after adding some output constraints.
1247 /// In the case where there is one output and one input and we add one output,
1248 /// we need to replace all operand references greater than or equal to 1:
1249 ///     mov $0, $1
1250 ///     mov eax, $1
1251 /// The result will be:
1252 ///     mov $0, $2
1253 ///     mov eax, $2
rewriteInputConstraintReferences(unsigned FirstIn,unsigned NumNewOuts,std::string & AsmString)1254 static void rewriteInputConstraintReferences(unsigned FirstIn,
1255                                              unsigned NumNewOuts,
1256                                              std::string &AsmString) {
1257   std::string Buf;
1258   llvm::raw_string_ostream OS(Buf);
1259   size_t Pos = 0;
1260   while (Pos < AsmString.size()) {
1261     size_t DollarStart = AsmString.find('$', Pos);
1262     if (DollarStart == std::string::npos)
1263       DollarStart = AsmString.size();
1264     size_t DollarEnd = AsmString.find_first_not_of('$', DollarStart);
1265     if (DollarEnd == std::string::npos)
1266       DollarEnd = AsmString.size();
1267     OS << StringRef(&AsmString[Pos], DollarEnd - Pos);
1268     Pos = DollarEnd;
1269     size_t NumDollars = DollarEnd - DollarStart;
1270     if (NumDollars % 2 != 0 && Pos < AsmString.size()) {
1271       // We have an operand reference.
1272       size_t DigitStart = Pos;
1273       if (AsmString[DigitStart] == '{') {
1274         OS << '{';
1275         ++DigitStart;
1276       }
1277       size_t DigitEnd = AsmString.find_first_not_of("0123456789", DigitStart);
1278       if (DigitEnd == std::string::npos)
1279         DigitEnd = AsmString.size();
1280       StringRef OperandStr(&AsmString[DigitStart], DigitEnd - DigitStart);
1281       unsigned OperandIndex;
1282       if (!OperandStr.getAsInteger(10, OperandIndex)) {
1283         if (OperandIndex >= FirstIn)
1284           OperandIndex += NumNewOuts;
1285         OS << OperandIndex;
1286       } else {
1287         OS << OperandStr;
1288       }
1289       Pos = DigitEnd;
1290     }
1291   }
1292   AsmString = std::move(OS.str());
1293 }
1294 
1295 /// Add output constraints for EAX:EDX because they are return registers.
addReturnRegisterOutputs(CodeGenFunction & CGF,LValue ReturnSlot,std::string & Constraints,std::vector<llvm::Type * > & ResultRegTypes,std::vector<llvm::Type * > & ResultTruncRegTypes,std::vector<LValue> & ResultRegDests,std::string & AsmString,unsigned NumOutputs) const1296 void X86_32TargetCodeGenInfo::addReturnRegisterOutputs(
1297     CodeGenFunction &CGF, LValue ReturnSlot, std::string &Constraints,
1298     std::vector<llvm::Type *> &ResultRegTypes,
1299     std::vector<llvm::Type *> &ResultTruncRegTypes,
1300     std::vector<LValue> &ResultRegDests, std::string &AsmString,
1301     unsigned NumOutputs) const {
1302   uint64_t RetWidth = CGF.getContext().getTypeSize(ReturnSlot.getType());
1303 
1304   // Use the EAX constraint if the width is 32 or smaller and EAX:EDX if it is
1305   // larger.
1306   if (!Constraints.empty())
1307     Constraints += ',';
1308   if (RetWidth <= 32) {
1309     Constraints += "={eax}";
1310     ResultRegTypes.push_back(CGF.Int32Ty);
1311   } else {
1312     // Use the 'A' constraint for EAX:EDX.
1313     Constraints += "=A";
1314     ResultRegTypes.push_back(CGF.Int64Ty);
1315   }
1316 
1317   // Truncate EAX or EAX:EDX to an integer of the appropriate size.
1318   llvm::Type *CoerceTy = llvm::IntegerType::get(CGF.getLLVMContext(), RetWidth);
1319   ResultTruncRegTypes.push_back(CoerceTy);
1320 
1321   // Coerce the integer by bitcasting the return slot pointer.
1322   ReturnSlot.setAddress(CGF.Builder.CreateBitCast(ReturnSlot.getAddress(CGF),
1323                                                   CoerceTy->getPointerTo()));
1324   ResultRegDests.push_back(ReturnSlot);
1325 
1326   rewriteInputConstraintReferences(NumOutputs, 1, AsmString);
1327 }
1328 
1329 /// shouldReturnTypeInRegister - Determine if the given type should be
1330 /// returned in a register (for the Darwin and MCU ABI).
shouldReturnTypeInRegister(QualType Ty,ASTContext & Context) const1331 bool X86_32ABIInfo::shouldReturnTypeInRegister(QualType Ty,
1332                                                ASTContext &Context) const {
1333   uint64_t Size = Context.getTypeSize(Ty);
1334 
1335   // For i386, type must be register sized.
1336   // For the MCU ABI, it only needs to be <= 8-byte
1337   if ((IsMCUABI && Size > 64) || (!IsMCUABI && !isRegisterSize(Size)))
1338    return false;
1339 
1340   if (Ty->isVectorType()) {
1341     // 64- and 128- bit vectors inside structures are not returned in
1342     // registers.
1343     if (Size == 64 || Size == 128)
1344       return false;
1345 
1346     return true;
1347   }
1348 
1349   // If this is a builtin, pointer, enum, complex type, member pointer, or
1350   // member function pointer it is ok.
1351   if (Ty->getAs<BuiltinType>() || Ty->hasPointerRepresentation() ||
1352       Ty->isAnyComplexType() || Ty->isEnumeralType() ||
1353       Ty->isBlockPointerType() || Ty->isMemberPointerType())
1354     return true;
1355 
1356   // Arrays are treated like records.
1357   if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty))
1358     return shouldReturnTypeInRegister(AT->getElementType(), Context);
1359 
1360   // Otherwise, it must be a record type.
1361   const RecordType *RT = Ty->getAs<RecordType>();
1362   if (!RT) return false;
1363 
1364   // FIXME: Traverse bases here too.
1365 
1366   // Structure types are passed in register if all fields would be
1367   // passed in a register.
1368   for (const auto *FD : RT->getDecl()->fields()) {
1369     // Empty fields are ignored.
1370     if (isEmptyField(Context, FD, true))
1371       continue;
1372 
1373     // Check fields recursively.
1374     if (!shouldReturnTypeInRegister(FD->getType(), Context))
1375       return false;
1376   }
1377   return true;
1378 }
1379 
is32Or64BitBasicType(QualType Ty,ASTContext & Context)1380 static bool is32Or64BitBasicType(QualType Ty, ASTContext &Context) {
1381   // Treat complex types as the element type.
1382   if (const ComplexType *CTy = Ty->getAs<ComplexType>())
1383     Ty = CTy->getElementType();
1384 
1385   // Check for a type which we know has a simple scalar argument-passing
1386   // convention without any padding.  (We're specifically looking for 32
1387   // and 64-bit integer and integer-equivalents, float, and double.)
1388   if (!Ty->getAs<BuiltinType>() && !Ty->hasPointerRepresentation() &&
1389       !Ty->isEnumeralType() && !Ty->isBlockPointerType())
1390     return false;
1391 
1392   uint64_t Size = Context.getTypeSize(Ty);
1393   return Size == 32 || Size == 64;
1394 }
1395 
addFieldSizes(ASTContext & Context,const RecordDecl * RD,uint64_t & Size)1396 static bool addFieldSizes(ASTContext &Context, const RecordDecl *RD,
1397                           uint64_t &Size) {
1398   for (const auto *FD : RD->fields()) {
1399     // Scalar arguments on the stack get 4 byte alignment on x86. If the
1400     // argument is smaller than 32-bits, expanding the struct will create
1401     // alignment padding.
1402     if (!is32Or64BitBasicType(FD->getType(), Context))
1403       return false;
1404 
1405     // FIXME: Reject bit-fields wholesale; there are two problems, we don't know
1406     // how to expand them yet, and the predicate for telling if a bitfield still
1407     // counts as "basic" is more complicated than what we were doing previously.
1408     if (FD->isBitField())
1409       return false;
1410 
1411     Size += Context.getTypeSize(FD->getType());
1412   }
1413   return true;
1414 }
1415 
addBaseAndFieldSizes(ASTContext & Context,const CXXRecordDecl * RD,uint64_t & Size)1416 static bool addBaseAndFieldSizes(ASTContext &Context, const CXXRecordDecl *RD,
1417                                  uint64_t &Size) {
1418   // Don't do this if there are any non-empty bases.
1419   for (const CXXBaseSpecifier &Base : RD->bases()) {
1420     if (!addBaseAndFieldSizes(Context, Base.getType()->getAsCXXRecordDecl(),
1421                               Size))
1422       return false;
1423   }
1424   if (!addFieldSizes(Context, RD, Size))
1425     return false;
1426   return true;
1427 }
1428 
1429 /// Test whether an argument type which is to be passed indirectly (on the
1430 /// stack) would have the equivalent layout if it was expanded into separate
1431 /// arguments. If so, we prefer to do the latter to avoid inhibiting
1432 /// optimizations.
canExpandIndirectArgument(QualType Ty) const1433 bool X86_32ABIInfo::canExpandIndirectArgument(QualType Ty) const {
1434   // We can only expand structure types.
1435   const RecordType *RT = Ty->getAs<RecordType>();
1436   if (!RT)
1437     return false;
1438   const RecordDecl *RD = RT->getDecl();
1439   uint64_t Size = 0;
1440   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
1441     if (!IsWin32StructABI) {
1442       // On non-Windows, we have to conservatively match our old bitcode
1443       // prototypes in order to be ABI-compatible at the bitcode level.
1444       if (!CXXRD->isCLike())
1445         return false;
1446     } else {
1447       // Don't do this for dynamic classes.
1448       if (CXXRD->isDynamicClass())
1449         return false;
1450     }
1451     if (!addBaseAndFieldSizes(getContext(), CXXRD, Size))
1452       return false;
1453   } else {
1454     if (!addFieldSizes(getContext(), RD, Size))
1455       return false;
1456   }
1457 
1458   // We can do this if there was no alignment padding.
1459   return Size == getContext().getTypeSize(Ty);
1460 }
1461 
getIndirectReturnResult(QualType RetTy,CCState & State) const1462 ABIArgInfo X86_32ABIInfo::getIndirectReturnResult(QualType RetTy, CCState &State) const {
1463   // If the return value is indirect, then the hidden argument is consuming one
1464   // integer register.
1465   if (State.FreeRegs) {
1466     --State.FreeRegs;
1467     if (!IsMCUABI)
1468       return getNaturalAlignIndirectInReg(RetTy);
1469   }
1470   return getNaturalAlignIndirect(RetTy, /*ByVal=*/false);
1471 }
1472 
classifyReturnType(QualType RetTy,CCState & State) const1473 ABIArgInfo X86_32ABIInfo::classifyReturnType(QualType RetTy,
1474                                              CCState &State) const {
1475   if (RetTy->isVoidType())
1476     return ABIArgInfo::getIgnore();
1477 
1478   const Type *Base = nullptr;
1479   uint64_t NumElts = 0;
1480   if ((State.CC == llvm::CallingConv::X86_VectorCall ||
1481        State.CC == llvm::CallingConv::X86_RegCall) &&
1482       isHomogeneousAggregate(RetTy, Base, NumElts)) {
1483     // The LLVM struct type for such an aggregate should lower properly.
1484     return ABIArgInfo::getDirect();
1485   }
1486 
1487   if (const VectorType *VT = RetTy->getAs<VectorType>()) {
1488     // On Darwin, some vectors are returned in registers.
1489     if (IsDarwinVectorABI) {
1490       uint64_t Size = getContext().getTypeSize(RetTy);
1491 
1492       // 128-bit vectors are a special case; they are returned in
1493       // registers and we need to make sure to pick a type the LLVM
1494       // backend will like.
1495       if (Size == 128)
1496         return ABIArgInfo::getDirect(llvm::FixedVectorType::get(
1497             llvm::Type::getInt64Ty(getVMContext()), 2));
1498 
1499       // Always return in register if it fits in a general purpose
1500       // register, or if it is 64 bits and has a single element.
1501       if ((Size == 8 || Size == 16 || Size == 32) ||
1502           (Size == 64 && VT->getNumElements() == 1))
1503         return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
1504                                                             Size));
1505 
1506       return getIndirectReturnResult(RetTy, State);
1507     }
1508 
1509     return ABIArgInfo::getDirect();
1510   }
1511 
1512   if (isAggregateTypeForABI(RetTy)) {
1513     if (const RecordType *RT = RetTy->getAs<RecordType>()) {
1514       // Structures with flexible arrays are always indirect.
1515       if (RT->getDecl()->hasFlexibleArrayMember())
1516         return getIndirectReturnResult(RetTy, State);
1517     }
1518 
1519     // If specified, structs and unions are always indirect.
1520     if (!IsRetSmallStructInRegABI && !RetTy->isAnyComplexType())
1521       return getIndirectReturnResult(RetTy, State);
1522 
1523     // Ignore empty structs/unions.
1524     if (isEmptyRecord(getContext(), RetTy, true))
1525       return ABIArgInfo::getIgnore();
1526 
1527     // Small structures which are register sized are generally returned
1528     // in a register.
1529     if (shouldReturnTypeInRegister(RetTy, getContext())) {
1530       uint64_t Size = getContext().getTypeSize(RetTy);
1531 
1532       // As a special-case, if the struct is a "single-element" struct, and
1533       // the field is of type "float" or "double", return it in a
1534       // floating-point register. (MSVC does not apply this special case.)
1535       // We apply a similar transformation for pointer types to improve the
1536       // quality of the generated IR.
1537       if (const Type *SeltTy = isSingleElementStruct(RetTy, getContext()))
1538         if ((!IsWin32StructABI && SeltTy->isRealFloatingType())
1539             || SeltTy->hasPointerRepresentation())
1540           return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
1541 
1542       // FIXME: We should be able to narrow this integer in cases with dead
1543       // padding.
1544       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),Size));
1545     }
1546 
1547     return getIndirectReturnResult(RetTy, State);
1548   }
1549 
1550   // Treat an enum type as its underlying type.
1551   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
1552     RetTy = EnumTy->getDecl()->getIntegerType();
1553 
1554   if (const auto *EIT = RetTy->getAs<ExtIntType>())
1555     if (EIT->getNumBits() > 64)
1556       return getIndirectReturnResult(RetTy, State);
1557 
1558   return (isPromotableIntegerTypeForABI(RetTy) ? ABIArgInfo::getExtend(RetTy)
1559                                                : ABIArgInfo::getDirect());
1560 }
1561 
isSIMDVectorType(ASTContext & Context,QualType Ty)1562 static bool isSIMDVectorType(ASTContext &Context, QualType Ty) {
1563   return Ty->getAs<VectorType>() && Context.getTypeSize(Ty) == 128;
1564 }
1565 
isRecordWithSIMDVectorType(ASTContext & Context,QualType Ty)1566 static bool isRecordWithSIMDVectorType(ASTContext &Context, QualType Ty) {
1567   const RecordType *RT = Ty->getAs<RecordType>();
1568   if (!RT)
1569     return 0;
1570   const RecordDecl *RD = RT->getDecl();
1571 
1572   // If this is a C++ record, check the bases first.
1573   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
1574     for (const auto &I : CXXRD->bases())
1575       if (!isRecordWithSIMDVectorType(Context, I.getType()))
1576         return false;
1577 
1578   for (const auto *i : RD->fields()) {
1579     QualType FT = i->getType();
1580 
1581     if (isSIMDVectorType(Context, FT))
1582       return true;
1583 
1584     if (isRecordWithSIMDVectorType(Context, FT))
1585       return true;
1586   }
1587 
1588   return false;
1589 }
1590 
getTypeStackAlignInBytes(QualType Ty,unsigned Align) const1591 unsigned X86_32ABIInfo::getTypeStackAlignInBytes(QualType Ty,
1592                                                  unsigned Align) const {
1593   // Otherwise, if the alignment is less than or equal to the minimum ABI
1594   // alignment, just use the default; the backend will handle this.
1595   if (Align <= MinABIStackAlignInBytes)
1596     return 0; // Use default alignment.
1597 
1598   if (IsLinuxABI) {
1599     // Exclude other System V OS (e.g Darwin, PS4 and FreeBSD) since we don't
1600     // want to spend any effort dealing with the ramifications of ABI breaks.
1601     //
1602     // If the vector type is __m128/__m256/__m512, return the default alignment.
1603     if (Ty->isVectorType() && (Align == 16 || Align == 32 || Align == 64))
1604       return Align;
1605   }
1606   // On non-Darwin, the stack type alignment is always 4.
1607   if (!IsDarwinVectorABI) {
1608     // Set explicit alignment, since we may need to realign the top.
1609     return MinABIStackAlignInBytes;
1610   }
1611 
1612   // Otherwise, if the type contains an SSE vector type, the alignment is 16.
1613   if (Align >= 16 && (isSIMDVectorType(getContext(), Ty) ||
1614                       isRecordWithSIMDVectorType(getContext(), Ty)))
1615     return 16;
1616 
1617   return MinABIStackAlignInBytes;
1618 }
1619 
getIndirectResult(QualType Ty,bool ByVal,CCState & State) const1620 ABIArgInfo X86_32ABIInfo::getIndirectResult(QualType Ty, bool ByVal,
1621                                             CCState &State) const {
1622   if (!ByVal) {
1623     if (State.FreeRegs) {
1624       --State.FreeRegs; // Non-byval indirects just use one pointer.
1625       if (!IsMCUABI)
1626         return getNaturalAlignIndirectInReg(Ty);
1627     }
1628     return getNaturalAlignIndirect(Ty, false);
1629   }
1630 
1631   // Compute the byval alignment.
1632   unsigned TypeAlign = getContext().getTypeAlign(Ty) / 8;
1633   unsigned StackAlign = getTypeStackAlignInBytes(Ty, TypeAlign);
1634   if (StackAlign == 0)
1635     return ABIArgInfo::getIndirect(CharUnits::fromQuantity(4), /*ByVal=*/true);
1636 
1637   // If the stack alignment is less than the type alignment, realign the
1638   // argument.
1639   bool Realign = TypeAlign > StackAlign;
1640   return ABIArgInfo::getIndirect(CharUnits::fromQuantity(StackAlign),
1641                                  /*ByVal=*/true, Realign);
1642 }
1643 
classify(QualType Ty) const1644 X86_32ABIInfo::Class X86_32ABIInfo::classify(QualType Ty) const {
1645   const Type *T = isSingleElementStruct(Ty, getContext());
1646   if (!T)
1647     T = Ty.getTypePtr();
1648 
1649   if (const BuiltinType *BT = T->getAs<BuiltinType>()) {
1650     BuiltinType::Kind K = BT->getKind();
1651     if (K == BuiltinType::Float || K == BuiltinType::Double)
1652       return Float;
1653   }
1654   return Integer;
1655 }
1656 
updateFreeRegs(QualType Ty,CCState & State) const1657 bool X86_32ABIInfo::updateFreeRegs(QualType Ty, CCState &State) const {
1658   if (!IsSoftFloatABI) {
1659     Class C = classify(Ty);
1660     if (C == Float)
1661       return false;
1662   }
1663 
1664   unsigned Size = getContext().getTypeSize(Ty);
1665   unsigned SizeInRegs = (Size + 31) / 32;
1666 
1667   if (SizeInRegs == 0)
1668     return false;
1669 
1670   if (!IsMCUABI) {
1671     if (SizeInRegs > State.FreeRegs) {
1672       State.FreeRegs = 0;
1673       return false;
1674     }
1675   } else {
1676     // The MCU psABI allows passing parameters in-reg even if there are
1677     // earlier parameters that are passed on the stack. Also,
1678     // it does not allow passing >8-byte structs in-register,
1679     // even if there are 3 free registers available.
1680     if (SizeInRegs > State.FreeRegs || SizeInRegs > 2)
1681       return false;
1682   }
1683 
1684   State.FreeRegs -= SizeInRegs;
1685   return true;
1686 }
1687 
shouldAggregateUseDirect(QualType Ty,CCState & State,bool & InReg,bool & NeedsPadding) const1688 bool X86_32ABIInfo::shouldAggregateUseDirect(QualType Ty, CCState &State,
1689                                              bool &InReg,
1690                                              bool &NeedsPadding) const {
1691   // On Windows, aggregates other than HFAs are never passed in registers, and
1692   // they do not consume register slots. Homogenous floating-point aggregates
1693   // (HFAs) have already been dealt with at this point.
1694   if (IsWin32StructABI && isAggregateTypeForABI(Ty))
1695     return false;
1696 
1697   NeedsPadding = false;
1698   InReg = !IsMCUABI;
1699 
1700   if (!updateFreeRegs(Ty, State))
1701     return false;
1702 
1703   if (IsMCUABI)
1704     return true;
1705 
1706   if (State.CC == llvm::CallingConv::X86_FastCall ||
1707       State.CC == llvm::CallingConv::X86_VectorCall ||
1708       State.CC == llvm::CallingConv::X86_RegCall) {
1709     if (getContext().getTypeSize(Ty) <= 32 && State.FreeRegs)
1710       NeedsPadding = true;
1711 
1712     return false;
1713   }
1714 
1715   return true;
1716 }
1717 
shouldPrimitiveUseInReg(QualType Ty,CCState & State) const1718 bool X86_32ABIInfo::shouldPrimitiveUseInReg(QualType Ty, CCState &State) const {
1719   if (!updateFreeRegs(Ty, State))
1720     return false;
1721 
1722   if (IsMCUABI)
1723     return false;
1724 
1725   if (State.CC == llvm::CallingConv::X86_FastCall ||
1726       State.CC == llvm::CallingConv::X86_VectorCall ||
1727       State.CC == llvm::CallingConv::X86_RegCall) {
1728     if (getContext().getTypeSize(Ty) > 32)
1729       return false;
1730 
1731     return (Ty->isIntegralOrEnumerationType() || Ty->isPointerType() ||
1732         Ty->isReferenceType());
1733   }
1734 
1735   return true;
1736 }
1737 
runVectorCallFirstPass(CGFunctionInfo & FI,CCState & State) const1738 void X86_32ABIInfo::runVectorCallFirstPass(CGFunctionInfo &FI, CCState &State) const {
1739   // Vectorcall x86 works subtly different than in x64, so the format is
1740   // a bit different than the x64 version.  First, all vector types (not HVAs)
1741   // are assigned, with the first 6 ending up in the [XYZ]MM0-5 registers.
1742   // This differs from the x64 implementation, where the first 6 by INDEX get
1743   // registers.
1744   // In the second pass over the arguments, HVAs are passed in the remaining
1745   // vector registers if possible, or indirectly by address. The address will be
1746   // passed in ECX/EDX if available. Any other arguments are passed according to
1747   // the usual fastcall rules.
1748   MutableArrayRef<CGFunctionInfoArgInfo> Args = FI.arguments();
1749   for (int I = 0, E = Args.size(); I < E; ++I) {
1750     const Type *Base = nullptr;
1751     uint64_t NumElts = 0;
1752     const QualType &Ty = Args[I].type;
1753     if ((Ty->isVectorType() || Ty->isBuiltinType()) &&
1754         isHomogeneousAggregate(Ty, Base, NumElts)) {
1755       if (State.FreeSSERegs >= NumElts) {
1756         State.FreeSSERegs -= NumElts;
1757         Args[I].info = ABIArgInfo::getDirectInReg();
1758         State.IsPreassigned.set(I);
1759       }
1760     }
1761   }
1762 }
1763 
classifyArgumentType(QualType Ty,CCState & State) const1764 ABIArgInfo X86_32ABIInfo::classifyArgumentType(QualType Ty,
1765                                                CCState &State) const {
1766   // FIXME: Set alignment on indirect arguments.
1767   bool IsFastCall = State.CC == llvm::CallingConv::X86_FastCall;
1768   bool IsRegCall = State.CC == llvm::CallingConv::X86_RegCall;
1769   bool IsVectorCall = State.CC == llvm::CallingConv::X86_VectorCall;
1770 
1771   Ty = useFirstFieldIfTransparentUnion(Ty);
1772   TypeInfo TI = getContext().getTypeInfo(Ty);
1773 
1774   // Check with the C++ ABI first.
1775   const RecordType *RT = Ty->getAs<RecordType>();
1776   if (RT) {
1777     CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, getCXXABI());
1778     if (RAA == CGCXXABI::RAA_Indirect) {
1779       return getIndirectResult(Ty, false, State);
1780     } else if (RAA == CGCXXABI::RAA_DirectInMemory) {
1781       // The field index doesn't matter, we'll fix it up later.
1782       return ABIArgInfo::getInAlloca(/*FieldIndex=*/0);
1783     }
1784   }
1785 
1786   // Regcall uses the concept of a homogenous vector aggregate, similar
1787   // to other targets.
1788   const Type *Base = nullptr;
1789   uint64_t NumElts = 0;
1790   if ((IsRegCall || IsVectorCall) &&
1791       isHomogeneousAggregate(Ty, Base, NumElts)) {
1792     if (State.FreeSSERegs >= NumElts) {
1793       State.FreeSSERegs -= NumElts;
1794 
1795       // Vectorcall passes HVAs directly and does not flatten them, but regcall
1796       // does.
1797       if (IsVectorCall)
1798         return getDirectX86Hva();
1799 
1800       if (Ty->isBuiltinType() || Ty->isVectorType())
1801         return ABIArgInfo::getDirect();
1802       return ABIArgInfo::getExpand();
1803     }
1804     return getIndirectResult(Ty, /*ByVal=*/false, State);
1805   }
1806 
1807   if (isAggregateTypeForABI(Ty)) {
1808     // Structures with flexible arrays are always indirect.
1809     // FIXME: This should not be byval!
1810     if (RT && RT->getDecl()->hasFlexibleArrayMember())
1811       return getIndirectResult(Ty, true, State);
1812 
1813     // Ignore empty structs/unions on non-Windows.
1814     if (!IsWin32StructABI && isEmptyRecord(getContext(), Ty, true))
1815       return ABIArgInfo::getIgnore();
1816 
1817     llvm::LLVMContext &LLVMContext = getVMContext();
1818     llvm::IntegerType *Int32 = llvm::Type::getInt32Ty(LLVMContext);
1819     bool NeedsPadding = false;
1820     bool InReg;
1821     if (shouldAggregateUseDirect(Ty, State, InReg, NeedsPadding)) {
1822       unsigned SizeInRegs = (TI.Width + 31) / 32;
1823       SmallVector<llvm::Type*, 3> Elements(SizeInRegs, Int32);
1824       llvm::Type *Result = llvm::StructType::get(LLVMContext, Elements);
1825       if (InReg)
1826         return ABIArgInfo::getDirectInReg(Result);
1827       else
1828         return ABIArgInfo::getDirect(Result);
1829     }
1830     llvm::IntegerType *PaddingType = NeedsPadding ? Int32 : nullptr;
1831 
1832     // Pass over-aligned aggregates on Windows indirectly. This behavior was
1833     // added in MSVC 2015.
1834     if (IsWin32StructABI && TI.AlignIsRequired && TI.Align > 32)
1835       return getIndirectResult(Ty, /*ByVal=*/false, State);
1836 
1837     // Expand small (<= 128-bit) record types when we know that the stack layout
1838     // of those arguments will match the struct. This is important because the
1839     // LLVM backend isn't smart enough to remove byval, which inhibits many
1840     // optimizations.
1841     // Don't do this for the MCU if there are still free integer registers
1842     // (see X86_64 ABI for full explanation).
1843     if (TI.Width <= 4 * 32 && (!IsMCUABI || State.FreeRegs == 0) &&
1844         canExpandIndirectArgument(Ty))
1845       return ABIArgInfo::getExpandWithPadding(
1846           IsFastCall || IsVectorCall || IsRegCall, PaddingType);
1847 
1848     return getIndirectResult(Ty, true, State);
1849   }
1850 
1851   if (const VectorType *VT = Ty->getAs<VectorType>()) {
1852     // On Windows, vectors are passed directly if registers are available, or
1853     // indirectly if not. This avoids the need to align argument memory. Pass
1854     // user-defined vector types larger than 512 bits indirectly for simplicity.
1855     if (IsWin32StructABI) {
1856       if (TI.Width <= 512 && State.FreeSSERegs > 0) {
1857         --State.FreeSSERegs;
1858         return ABIArgInfo::getDirectInReg();
1859       }
1860       return getIndirectResult(Ty, /*ByVal=*/false, State);
1861     }
1862 
1863     // On Darwin, some vectors are passed in memory, we handle this by passing
1864     // it as an i8/i16/i32/i64.
1865     if (IsDarwinVectorABI) {
1866       if ((TI.Width == 8 || TI.Width == 16 || TI.Width == 32) ||
1867           (TI.Width == 64 && VT->getNumElements() == 1))
1868         return ABIArgInfo::getDirect(
1869             llvm::IntegerType::get(getVMContext(), TI.Width));
1870     }
1871 
1872     if (IsX86_MMXType(CGT.ConvertType(Ty)))
1873       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), 64));
1874 
1875     return ABIArgInfo::getDirect();
1876   }
1877 
1878 
1879   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
1880     Ty = EnumTy->getDecl()->getIntegerType();
1881 
1882   bool InReg = shouldPrimitiveUseInReg(Ty, State);
1883 
1884   if (isPromotableIntegerTypeForABI(Ty)) {
1885     if (InReg)
1886       return ABIArgInfo::getExtendInReg(Ty);
1887     return ABIArgInfo::getExtend(Ty);
1888   }
1889 
1890   if (const auto * EIT = Ty->getAs<ExtIntType>()) {
1891     if (EIT->getNumBits() <= 64) {
1892       if (InReg)
1893         return ABIArgInfo::getDirectInReg();
1894       return ABIArgInfo::getDirect();
1895     }
1896     return getIndirectResult(Ty, /*ByVal=*/false, State);
1897   }
1898 
1899   if (InReg)
1900     return ABIArgInfo::getDirectInReg();
1901   return ABIArgInfo::getDirect();
1902 }
1903 
computeInfo(CGFunctionInfo & FI) const1904 void X86_32ABIInfo::computeInfo(CGFunctionInfo &FI) const {
1905   CCState State(FI);
1906   if (IsMCUABI)
1907     State.FreeRegs = 3;
1908   else if (State.CC == llvm::CallingConv::X86_FastCall) {
1909     State.FreeRegs = 2;
1910     State.FreeSSERegs = 3;
1911   } else if (State.CC == llvm::CallingConv::X86_VectorCall) {
1912     State.FreeRegs = 2;
1913     State.FreeSSERegs = 6;
1914   } else if (FI.getHasRegParm())
1915     State.FreeRegs = FI.getRegParm();
1916   else if (State.CC == llvm::CallingConv::X86_RegCall) {
1917     State.FreeRegs = 5;
1918     State.FreeSSERegs = 8;
1919   } else if (IsWin32StructABI) {
1920     // Since MSVC 2015, the first three SSE vectors have been passed in
1921     // registers. The rest are passed indirectly.
1922     State.FreeRegs = DefaultNumRegisterParameters;
1923     State.FreeSSERegs = 3;
1924   } else
1925     State.FreeRegs = DefaultNumRegisterParameters;
1926 
1927   if (!::classifyReturnType(getCXXABI(), FI, *this)) {
1928     FI.getReturnInfo() = classifyReturnType(FI.getReturnType(), State);
1929   } else if (FI.getReturnInfo().isIndirect()) {
1930     // The C++ ABI is not aware of register usage, so we have to check if the
1931     // return value was sret and put it in a register ourselves if appropriate.
1932     if (State.FreeRegs) {
1933       --State.FreeRegs;  // The sret parameter consumes a register.
1934       if (!IsMCUABI)
1935         FI.getReturnInfo().setInReg(true);
1936     }
1937   }
1938 
1939   // The chain argument effectively gives us another free register.
1940   if (FI.isChainCall())
1941     ++State.FreeRegs;
1942 
1943   // For vectorcall, do a first pass over the arguments, assigning FP and vector
1944   // arguments to XMM registers as available.
1945   if (State.CC == llvm::CallingConv::X86_VectorCall)
1946     runVectorCallFirstPass(FI, State);
1947 
1948   bool UsedInAlloca = false;
1949   MutableArrayRef<CGFunctionInfoArgInfo> Args = FI.arguments();
1950   for (int I = 0, E = Args.size(); I < E; ++I) {
1951     // Skip arguments that have already been assigned.
1952     if (State.IsPreassigned.test(I))
1953       continue;
1954 
1955     Args[I].info = classifyArgumentType(Args[I].type, State);
1956     UsedInAlloca |= (Args[I].info.getKind() == ABIArgInfo::InAlloca);
1957   }
1958 
1959   // If we needed to use inalloca for any argument, do a second pass and rewrite
1960   // all the memory arguments to use inalloca.
1961   if (UsedInAlloca)
1962     rewriteWithInAlloca(FI);
1963 }
1964 
1965 void
addFieldToArgStruct(SmallVector<llvm::Type *,6> & FrameFields,CharUnits & StackOffset,ABIArgInfo & Info,QualType Type) const1966 X86_32ABIInfo::addFieldToArgStruct(SmallVector<llvm::Type *, 6> &FrameFields,
1967                                    CharUnits &StackOffset, ABIArgInfo &Info,
1968                                    QualType Type) const {
1969   // Arguments are always 4-byte-aligned.
1970   CharUnits WordSize = CharUnits::fromQuantity(4);
1971   assert(StackOffset.isMultipleOf(WordSize) && "unaligned inalloca struct");
1972 
1973   // sret pointers and indirect things will require an extra pointer
1974   // indirection, unless they are byval. Most things are byval, and will not
1975   // require this indirection.
1976   bool IsIndirect = false;
1977   if (Info.isIndirect() && !Info.getIndirectByVal())
1978     IsIndirect = true;
1979   Info = ABIArgInfo::getInAlloca(FrameFields.size(), IsIndirect);
1980   llvm::Type *LLTy = CGT.ConvertTypeForMem(Type);
1981   if (IsIndirect)
1982     LLTy = LLTy->getPointerTo(0);
1983   FrameFields.push_back(LLTy);
1984   StackOffset += IsIndirect ? WordSize : getContext().getTypeSizeInChars(Type);
1985 
1986   // Insert padding bytes to respect alignment.
1987   CharUnits FieldEnd = StackOffset;
1988   StackOffset = FieldEnd.alignTo(WordSize);
1989   if (StackOffset != FieldEnd) {
1990     CharUnits NumBytes = StackOffset - FieldEnd;
1991     llvm::Type *Ty = llvm::Type::getInt8Ty(getVMContext());
1992     Ty = llvm::ArrayType::get(Ty, NumBytes.getQuantity());
1993     FrameFields.push_back(Ty);
1994   }
1995 }
1996 
isArgInAlloca(const ABIArgInfo & Info)1997 static bool isArgInAlloca(const ABIArgInfo &Info) {
1998   // Leave ignored and inreg arguments alone.
1999   switch (Info.getKind()) {
2000   case ABIArgInfo::InAlloca:
2001     return true;
2002   case ABIArgInfo::Ignore:
2003   case ABIArgInfo::IndirectAliased:
2004     return false;
2005   case ABIArgInfo::Indirect:
2006   case ABIArgInfo::Direct:
2007   case ABIArgInfo::Extend:
2008     return !Info.getInReg();
2009   case ABIArgInfo::Expand:
2010   case ABIArgInfo::CoerceAndExpand:
2011     // These are aggregate types which are never passed in registers when
2012     // inalloca is involved.
2013     return true;
2014   }
2015   llvm_unreachable("invalid enum");
2016 }
2017 
rewriteWithInAlloca(CGFunctionInfo & FI) const2018 void X86_32ABIInfo::rewriteWithInAlloca(CGFunctionInfo &FI) const {
2019   assert(IsWin32StructABI && "inalloca only supported on win32");
2020 
2021   // Build a packed struct type for all of the arguments in memory.
2022   SmallVector<llvm::Type *, 6> FrameFields;
2023 
2024   // The stack alignment is always 4.
2025   CharUnits StackAlign = CharUnits::fromQuantity(4);
2026 
2027   CharUnits StackOffset;
2028   CGFunctionInfo::arg_iterator I = FI.arg_begin(), E = FI.arg_end();
2029 
2030   // Put 'this' into the struct before 'sret', if necessary.
2031   bool IsThisCall =
2032       FI.getCallingConvention() == llvm::CallingConv::X86_ThisCall;
2033   ABIArgInfo &Ret = FI.getReturnInfo();
2034   if (Ret.isIndirect() && Ret.isSRetAfterThis() && !IsThisCall &&
2035       isArgInAlloca(I->info)) {
2036     addFieldToArgStruct(FrameFields, StackOffset, I->info, I->type);
2037     ++I;
2038   }
2039 
2040   // Put the sret parameter into the inalloca struct if it's in memory.
2041   if (Ret.isIndirect() && !Ret.getInReg()) {
2042     addFieldToArgStruct(FrameFields, StackOffset, Ret, FI.getReturnType());
2043     // On Windows, the hidden sret parameter is always returned in eax.
2044     Ret.setInAllocaSRet(IsWin32StructABI);
2045   }
2046 
2047   // Skip the 'this' parameter in ecx.
2048   if (IsThisCall)
2049     ++I;
2050 
2051   // Put arguments passed in memory into the struct.
2052   for (; I != E; ++I) {
2053     if (isArgInAlloca(I->info))
2054       addFieldToArgStruct(FrameFields, StackOffset, I->info, I->type);
2055   }
2056 
2057   FI.setArgStruct(llvm::StructType::get(getVMContext(), FrameFields,
2058                                         /*isPacked=*/true),
2059                   StackAlign);
2060 }
2061 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const2062 Address X86_32ABIInfo::EmitVAArg(CodeGenFunction &CGF,
2063                                  Address VAListAddr, QualType Ty) const {
2064 
2065   auto TypeInfo = getContext().getTypeInfoInChars(Ty);
2066 
2067   // x86-32 changes the alignment of certain arguments on the stack.
2068   //
2069   // Just messing with TypeInfo like this works because we never pass
2070   // anything indirectly.
2071   TypeInfo.Align = CharUnits::fromQuantity(
2072                 getTypeStackAlignInBytes(Ty, TypeInfo.Align.getQuantity()));
2073 
2074   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*Indirect*/ false,
2075                           TypeInfo, CharUnits::fromQuantity(4),
2076                           /*AllowHigherAlign*/ true);
2077 }
2078 
isStructReturnInRegABI(const llvm::Triple & Triple,const CodeGenOptions & Opts)2079 bool X86_32TargetCodeGenInfo::isStructReturnInRegABI(
2080     const llvm::Triple &Triple, const CodeGenOptions &Opts) {
2081   assert(Triple.getArch() == llvm::Triple::x86);
2082 
2083   switch (Opts.getStructReturnConvention()) {
2084   case CodeGenOptions::SRCK_Default:
2085     break;
2086   case CodeGenOptions::SRCK_OnStack:  // -fpcc-struct-return
2087     return false;
2088   case CodeGenOptions::SRCK_InRegs:  // -freg-struct-return
2089     return true;
2090   }
2091 
2092   if (Triple.isOSDarwin() || Triple.isOSIAMCU())
2093     return true;
2094 
2095   switch (Triple.getOS()) {
2096   case llvm::Triple::DragonFly:
2097   case llvm::Triple::FreeBSD:
2098   case llvm::Triple::OpenBSD:
2099   case llvm::Triple::Win32:
2100     return true;
2101   default:
2102     return false;
2103   }
2104 }
2105 
addX86InterruptAttrs(const FunctionDecl * FD,llvm::GlobalValue * GV,CodeGen::CodeGenModule & CGM)2106 static void addX86InterruptAttrs(const FunctionDecl *FD, llvm::GlobalValue *GV,
2107                                  CodeGen::CodeGenModule &CGM) {
2108   if (!FD->hasAttr<AnyX86InterruptAttr>())
2109     return;
2110 
2111   llvm::Function *Fn = cast<llvm::Function>(GV);
2112   Fn->setCallingConv(llvm::CallingConv::X86_INTR);
2113   if (FD->getNumParams() == 0)
2114     return;
2115 
2116   auto PtrTy = cast<PointerType>(FD->getParamDecl(0)->getType());
2117   llvm::Type *ByValTy = CGM.getTypes().ConvertType(PtrTy->getPointeeType());
2118   llvm::Attribute NewAttr = llvm::Attribute::getWithByValType(
2119     Fn->getContext(), ByValTy);
2120   Fn->addParamAttr(0, NewAttr);
2121 }
2122 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & CGM) const2123 void X86_32TargetCodeGenInfo::setTargetAttributes(
2124     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &CGM) const {
2125   if (GV->isDeclaration())
2126     return;
2127   if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D)) {
2128     if (FD->hasAttr<X86ForceAlignArgPointerAttr>()) {
2129       llvm::Function *Fn = cast<llvm::Function>(GV);
2130       Fn->addFnAttr("stackrealign");
2131     }
2132 
2133     addX86InterruptAttrs(FD, GV, CGM);
2134   }
2135 }
2136 
initDwarfEHRegSizeTable(CodeGen::CodeGenFunction & CGF,llvm::Value * Address) const2137 bool X86_32TargetCodeGenInfo::initDwarfEHRegSizeTable(
2138                                                CodeGen::CodeGenFunction &CGF,
2139                                                llvm::Value *Address) const {
2140   CodeGen::CGBuilderTy &Builder = CGF.Builder;
2141 
2142   llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
2143 
2144   // 0-7 are the eight integer registers;  the order is different
2145   //   on Darwin (for EH), but the range is the same.
2146   // 8 is %eip.
2147   AssignToArrayRange(Builder, Address, Four8, 0, 8);
2148 
2149   if (CGF.CGM.getTarget().getTriple().isOSDarwin()) {
2150     // 12-16 are st(0..4).  Not sure why we stop at 4.
2151     // These have size 16, which is sizeof(long double) on
2152     // platforms with 8-byte alignment for that type.
2153     llvm::Value *Sixteen8 = llvm::ConstantInt::get(CGF.Int8Ty, 16);
2154     AssignToArrayRange(Builder, Address, Sixteen8, 12, 16);
2155 
2156   } else {
2157     // 9 is %eflags, which doesn't get a size on Darwin for some
2158     // reason.
2159     Builder.CreateAlignedStore(
2160         Four8, Builder.CreateConstInBoundsGEP1_32(CGF.Int8Ty, Address, 9),
2161                                CharUnits::One());
2162 
2163     // 11-16 are st(0..5).  Not sure why we stop at 5.
2164     // These have size 12, which is sizeof(long double) on
2165     // platforms with 4-byte alignment for that type.
2166     llvm::Value *Twelve8 = llvm::ConstantInt::get(CGF.Int8Ty, 12);
2167     AssignToArrayRange(Builder, Address, Twelve8, 11, 16);
2168   }
2169 
2170   return false;
2171 }
2172 
2173 //===----------------------------------------------------------------------===//
2174 // X86-64 ABI Implementation
2175 //===----------------------------------------------------------------------===//
2176 
2177 
2178 namespace {
2179 /// The AVX ABI level for X86 targets.
2180 enum class X86AVXABILevel {
2181   None,
2182   AVX,
2183   AVX512
2184 };
2185 
2186 /// \p returns the size in bits of the largest (native) vector for \p AVXLevel.
getNativeVectorSizeForAVXABI(X86AVXABILevel AVXLevel)2187 static unsigned getNativeVectorSizeForAVXABI(X86AVXABILevel AVXLevel) {
2188   switch (AVXLevel) {
2189   case X86AVXABILevel::AVX512:
2190     return 512;
2191   case X86AVXABILevel::AVX:
2192     return 256;
2193   case X86AVXABILevel::None:
2194     return 128;
2195   }
2196   llvm_unreachable("Unknown AVXLevel");
2197 }
2198 
2199 /// X86_64ABIInfo - The X86_64 ABI information.
2200 class X86_64ABIInfo : public SwiftABIInfo {
2201   enum Class {
2202     Integer = 0,
2203     SSE,
2204     SSEUp,
2205     X87,
2206     X87Up,
2207     ComplexX87,
2208     NoClass,
2209     Memory
2210   };
2211 
2212   /// merge - Implement the X86_64 ABI merging algorithm.
2213   ///
2214   /// Merge an accumulating classification \arg Accum with a field
2215   /// classification \arg Field.
2216   ///
2217   /// \param Accum - The accumulating classification. This should
2218   /// always be either NoClass or the result of a previous merge
2219   /// call. In addition, this should never be Memory (the caller
2220   /// should just return Memory for the aggregate).
2221   static Class merge(Class Accum, Class Field);
2222 
2223   /// postMerge - Implement the X86_64 ABI post merging algorithm.
2224   ///
2225   /// Post merger cleanup, reduces a malformed Hi and Lo pair to
2226   /// final MEMORY or SSE classes when necessary.
2227   ///
2228   /// \param AggregateSize - The size of the current aggregate in
2229   /// the classification process.
2230   ///
2231   /// \param Lo - The classification for the parts of the type
2232   /// residing in the low word of the containing object.
2233   ///
2234   /// \param Hi - The classification for the parts of the type
2235   /// residing in the higher words of the containing object.
2236   ///
2237   void postMerge(unsigned AggregateSize, Class &Lo, Class &Hi) const;
2238 
2239   /// classify - Determine the x86_64 register classes in which the
2240   /// given type T should be passed.
2241   ///
2242   /// \param Lo - The classification for the parts of the type
2243   /// residing in the low word of the containing object.
2244   ///
2245   /// \param Hi - The classification for the parts of the type
2246   /// residing in the high word of the containing object.
2247   ///
2248   /// \param OffsetBase - The bit offset of this type in the
2249   /// containing object.  Some parameters are classified different
2250   /// depending on whether they straddle an eightbyte boundary.
2251   ///
2252   /// \param isNamedArg - Whether the argument in question is a "named"
2253   /// argument, as used in AMD64-ABI 3.5.7.
2254   ///
2255   /// If a word is unused its result will be NoClass; if a type should
2256   /// be passed in Memory then at least the classification of \arg Lo
2257   /// will be Memory.
2258   ///
2259   /// The \arg Lo class will be NoClass iff the argument is ignored.
2260   ///
2261   /// If the \arg Lo class is ComplexX87, then the \arg Hi class will
2262   /// also be ComplexX87.
2263   void classify(QualType T, uint64_t OffsetBase, Class &Lo, Class &Hi,
2264                 bool isNamedArg) const;
2265 
2266   llvm::Type *GetByteVectorType(QualType Ty) const;
2267   llvm::Type *GetSSETypeAtOffset(llvm::Type *IRType,
2268                                  unsigned IROffset, QualType SourceTy,
2269                                  unsigned SourceOffset) const;
2270   llvm::Type *GetINTEGERTypeAtOffset(llvm::Type *IRType,
2271                                      unsigned IROffset, QualType SourceTy,
2272                                      unsigned SourceOffset) const;
2273 
2274   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
2275   /// such that the argument will be returned in memory.
2276   ABIArgInfo getIndirectReturnResult(QualType Ty) const;
2277 
2278   /// getIndirectResult - Give a source type \arg Ty, return a suitable result
2279   /// such that the argument will be passed in memory.
2280   ///
2281   /// \param freeIntRegs - The number of free integer registers remaining
2282   /// available.
2283   ABIArgInfo getIndirectResult(QualType Ty, unsigned freeIntRegs) const;
2284 
2285   ABIArgInfo classifyReturnType(QualType RetTy) const;
2286 
2287   ABIArgInfo classifyArgumentType(QualType Ty, unsigned freeIntRegs,
2288                                   unsigned &neededInt, unsigned &neededSSE,
2289                                   bool isNamedArg) const;
2290 
2291   ABIArgInfo classifyRegCallStructType(QualType Ty, unsigned &NeededInt,
2292                                        unsigned &NeededSSE) const;
2293 
2294   ABIArgInfo classifyRegCallStructTypeImpl(QualType Ty, unsigned &NeededInt,
2295                                            unsigned &NeededSSE) const;
2296 
2297   bool IsIllegalVectorType(QualType Ty) const;
2298 
2299   /// The 0.98 ABI revision clarified a lot of ambiguities,
2300   /// unfortunately in ways that were not always consistent with
2301   /// certain previous compilers.  In particular, platforms which
2302   /// required strict binary compatibility with older versions of GCC
2303   /// may need to exempt themselves.
honorsRevision0_98() const2304   bool honorsRevision0_98() const {
2305     return !getTarget().getTriple().isOSDarwin();
2306   }
2307 
2308   /// GCC classifies <1 x long long> as SSE but some platform ABIs choose to
2309   /// classify it as INTEGER (for compatibility with older clang compilers).
classifyIntegerMMXAsSSE() const2310   bool classifyIntegerMMXAsSSE() const {
2311     // Clang <= 3.8 did not do this.
2312     if (getContext().getLangOpts().getClangABICompat() <=
2313         LangOptions::ClangABI::Ver3_8)
2314       return false;
2315 
2316     const llvm::Triple &Triple = getTarget().getTriple();
2317     if (Triple.isOSDarwin() || Triple.getOS() == llvm::Triple::PS4)
2318       return false;
2319     if (Triple.isOSFreeBSD() && Triple.getOSMajorVersion() >= 10)
2320       return false;
2321     return true;
2322   }
2323 
2324   // GCC classifies vectors of __int128 as memory.
passInt128VectorsInMem() const2325   bool passInt128VectorsInMem() const {
2326     // Clang <= 9.0 did not do this.
2327     if (getContext().getLangOpts().getClangABICompat() <=
2328         LangOptions::ClangABI::Ver9)
2329       return false;
2330 
2331     const llvm::Triple &T = getTarget().getTriple();
2332     return T.isOSLinux() || T.isOSNetBSD();
2333   }
2334 
2335   X86AVXABILevel AVXLevel;
2336   // Some ABIs (e.g. X32 ABI and Native Client OS) use 32 bit pointers on
2337   // 64-bit hardware.
2338   bool Has64BitPointers;
2339 
2340 public:
X86_64ABIInfo(CodeGen::CodeGenTypes & CGT,X86AVXABILevel AVXLevel)2341   X86_64ABIInfo(CodeGen::CodeGenTypes &CGT, X86AVXABILevel AVXLevel) :
2342       SwiftABIInfo(CGT), AVXLevel(AVXLevel),
2343       Has64BitPointers(CGT.getDataLayout().getPointerSize(0) == 8) {
2344   }
2345 
isPassedUsingAVXType(QualType type) const2346   bool isPassedUsingAVXType(QualType type) const {
2347     unsigned neededInt, neededSSE;
2348     // The freeIntRegs argument doesn't matter here.
2349     ABIArgInfo info = classifyArgumentType(type, 0, neededInt, neededSSE,
2350                                            /*isNamedArg*/true);
2351     if (info.isDirect()) {
2352       llvm::Type *ty = info.getCoerceToType();
2353       if (llvm::VectorType *vectorTy = dyn_cast_or_null<llvm::VectorType>(ty))
2354         return vectorTy->getPrimitiveSizeInBits().getFixedSize() > 128;
2355     }
2356     return false;
2357   }
2358 
2359   void computeInfo(CGFunctionInfo &FI) const override;
2360 
2361   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
2362                     QualType Ty) const override;
2363   Address EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
2364                       QualType Ty) const override;
2365 
has64BitPointers() const2366   bool has64BitPointers() const {
2367     return Has64BitPointers;
2368   }
2369 
shouldPassIndirectlyForSwift(ArrayRef<llvm::Type * > scalars,bool asReturnValue) const2370   bool shouldPassIndirectlyForSwift(ArrayRef<llvm::Type*> scalars,
2371                                     bool asReturnValue) const override {
2372     return occupiesMoreThan(CGT, scalars, /*total*/ 4);
2373   }
isSwiftErrorInRegister() const2374   bool isSwiftErrorInRegister() const override {
2375     return true;
2376   }
2377 };
2378 
2379 /// WinX86_64ABIInfo - The Windows X86_64 ABI information.
2380 class WinX86_64ABIInfo : public SwiftABIInfo {
2381 public:
WinX86_64ABIInfo(CodeGen::CodeGenTypes & CGT,X86AVXABILevel AVXLevel)2382   WinX86_64ABIInfo(CodeGen::CodeGenTypes &CGT, X86AVXABILevel AVXLevel)
2383       : SwiftABIInfo(CGT), AVXLevel(AVXLevel),
2384         IsMingw64(getTarget().getTriple().isWindowsGNUEnvironment()) {}
2385 
2386   void computeInfo(CGFunctionInfo &FI) const override;
2387 
2388   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
2389                     QualType Ty) const override;
2390 
isHomogeneousAggregateBaseType(QualType Ty) const2391   bool isHomogeneousAggregateBaseType(QualType Ty) const override {
2392     // FIXME: Assumes vectorcall is in use.
2393     return isX86VectorTypeForVectorCall(getContext(), Ty);
2394   }
2395 
isHomogeneousAggregateSmallEnough(const Type * Ty,uint64_t NumMembers) const2396   bool isHomogeneousAggregateSmallEnough(const Type *Ty,
2397                                          uint64_t NumMembers) const override {
2398     // FIXME: Assumes vectorcall is in use.
2399     return isX86VectorCallAggregateSmallEnough(NumMembers);
2400   }
2401 
shouldPassIndirectlyForSwift(ArrayRef<llvm::Type * > scalars,bool asReturnValue) const2402   bool shouldPassIndirectlyForSwift(ArrayRef<llvm::Type *> scalars,
2403                                     bool asReturnValue) const override {
2404     return occupiesMoreThan(CGT, scalars, /*total*/ 4);
2405   }
2406 
isSwiftErrorInRegister() const2407   bool isSwiftErrorInRegister() const override {
2408     return true;
2409   }
2410 
2411 private:
2412   ABIArgInfo classify(QualType Ty, unsigned &FreeSSERegs, bool IsReturnType,
2413                       bool IsVectorCall, bool IsRegCall) const;
2414   ABIArgInfo reclassifyHvaArgForVectorCall(QualType Ty, unsigned &FreeSSERegs,
2415                                            const ABIArgInfo &current) const;
2416 
2417   X86AVXABILevel AVXLevel;
2418 
2419   bool IsMingw64;
2420 };
2421 
2422 class X86_64TargetCodeGenInfo : public TargetCodeGenInfo {
2423 public:
X86_64TargetCodeGenInfo(CodeGen::CodeGenTypes & CGT,X86AVXABILevel AVXLevel)2424   X86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, X86AVXABILevel AVXLevel)
2425       : TargetCodeGenInfo(std::make_unique<X86_64ABIInfo>(CGT, AVXLevel)) {}
2426 
getABIInfo() const2427   const X86_64ABIInfo &getABIInfo() const {
2428     return static_cast<const X86_64ABIInfo&>(TargetCodeGenInfo::getABIInfo());
2429   }
2430 
2431   /// Disable tail call on x86-64. The epilogue code before the tail jump blocks
2432   /// autoreleaseRV/retainRV and autoreleaseRV/unsafeClaimRV optimizations.
markARCOptimizedReturnCallsAsNoTail() const2433   bool markARCOptimizedReturnCallsAsNoTail() const override { return true; }
2434 
getDwarfEHStackPointer(CodeGen::CodeGenModule & CGM) const2435   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
2436     return 7;
2437   }
2438 
initDwarfEHRegSizeTable(CodeGen::CodeGenFunction & CGF,llvm::Value * Address) const2439   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2440                                llvm::Value *Address) const override {
2441     llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
2442 
2443     // 0-15 are the 16 integer registers.
2444     // 16 is %rip.
2445     AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
2446     return false;
2447   }
2448 
adjustInlineAsmType(CodeGen::CodeGenFunction & CGF,StringRef Constraint,llvm::Type * Ty) const2449   llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
2450                                   StringRef Constraint,
2451                                   llvm::Type* Ty) const override {
2452     return X86AdjustInlineAsmType(CGF, Constraint, Ty);
2453   }
2454 
isNoProtoCallVariadic(const CallArgList & args,const FunctionNoProtoType * fnType) const2455   bool isNoProtoCallVariadic(const CallArgList &args,
2456                              const FunctionNoProtoType *fnType) const override {
2457     // The default CC on x86-64 sets %al to the number of SSA
2458     // registers used, and GCC sets this when calling an unprototyped
2459     // function, so we override the default behavior.  However, don't do
2460     // that when AVX types are involved: the ABI explicitly states it is
2461     // undefined, and it doesn't work in practice because of how the ABI
2462     // defines varargs anyway.
2463     if (fnType->getCallConv() == CC_C) {
2464       bool HasAVXType = false;
2465       for (CallArgList::const_iterator
2466              it = args.begin(), ie = args.end(); it != ie; ++it) {
2467         if (getABIInfo().isPassedUsingAVXType(it->Ty)) {
2468           HasAVXType = true;
2469           break;
2470         }
2471       }
2472 
2473       if (!HasAVXType)
2474         return true;
2475     }
2476 
2477     return TargetCodeGenInfo::isNoProtoCallVariadic(args, fnType);
2478   }
2479 
2480   llvm::Constant *
getUBSanFunctionSignature(CodeGen::CodeGenModule & CGM) const2481   getUBSanFunctionSignature(CodeGen::CodeGenModule &CGM) const override {
2482     unsigned Sig = (0xeb << 0) | // jmp rel8
2483                    (0x06 << 8) | //           .+0x08
2484                    ('v' << 16) |
2485                    ('2' << 24);
2486     return llvm::ConstantInt::get(CGM.Int32Ty, Sig);
2487   }
2488 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & CGM) const2489   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
2490                            CodeGen::CodeGenModule &CGM) const override {
2491     if (GV->isDeclaration())
2492       return;
2493     if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D)) {
2494       if (FD->hasAttr<X86ForceAlignArgPointerAttr>()) {
2495         llvm::Function *Fn = cast<llvm::Function>(GV);
2496         Fn->addFnAttr("stackrealign");
2497       }
2498 
2499       addX86InterruptAttrs(FD, GV, CGM);
2500     }
2501   }
2502 
2503   void checkFunctionCallABI(CodeGenModule &CGM, SourceLocation CallLoc,
2504                             const FunctionDecl *Caller,
2505                             const FunctionDecl *Callee,
2506                             const CallArgList &Args) const override;
2507 };
2508 
initFeatureMaps(const ASTContext & Ctx,llvm::StringMap<bool> & CallerMap,const FunctionDecl * Caller,llvm::StringMap<bool> & CalleeMap,const FunctionDecl * Callee)2509 static void initFeatureMaps(const ASTContext &Ctx,
2510                             llvm::StringMap<bool> &CallerMap,
2511                             const FunctionDecl *Caller,
2512                             llvm::StringMap<bool> &CalleeMap,
2513                             const FunctionDecl *Callee) {
2514   if (CalleeMap.empty() && CallerMap.empty()) {
2515     // The caller is potentially nullptr in the case where the call isn't in a
2516     // function.  In this case, the getFunctionFeatureMap ensures we just get
2517     // the TU level setting (since it cannot be modified by 'target'..
2518     Ctx.getFunctionFeatureMap(CallerMap, Caller);
2519     Ctx.getFunctionFeatureMap(CalleeMap, Callee);
2520   }
2521 }
2522 
checkAVXParamFeature(DiagnosticsEngine & Diag,SourceLocation CallLoc,const llvm::StringMap<bool> & CallerMap,const llvm::StringMap<bool> & CalleeMap,QualType Ty,StringRef Feature,bool IsArgument)2523 static bool checkAVXParamFeature(DiagnosticsEngine &Diag,
2524                                  SourceLocation CallLoc,
2525                                  const llvm::StringMap<bool> &CallerMap,
2526                                  const llvm::StringMap<bool> &CalleeMap,
2527                                  QualType Ty, StringRef Feature,
2528                                  bool IsArgument) {
2529   bool CallerHasFeat = CallerMap.lookup(Feature);
2530   bool CalleeHasFeat = CalleeMap.lookup(Feature);
2531   if (!CallerHasFeat && !CalleeHasFeat)
2532     return Diag.Report(CallLoc, diag::warn_avx_calling_convention)
2533            << IsArgument << Ty << Feature;
2534 
2535   // Mixing calling conventions here is very clearly an error.
2536   if (!CallerHasFeat || !CalleeHasFeat)
2537     return Diag.Report(CallLoc, diag::err_avx_calling_convention)
2538            << IsArgument << Ty << Feature;
2539 
2540   // Else, both caller and callee have the required feature, so there is no need
2541   // to diagnose.
2542   return false;
2543 }
2544 
checkAVXParam(DiagnosticsEngine & Diag,ASTContext & Ctx,SourceLocation CallLoc,const llvm::StringMap<bool> & CallerMap,const llvm::StringMap<bool> & CalleeMap,QualType Ty,bool IsArgument)2545 static bool checkAVXParam(DiagnosticsEngine &Diag, ASTContext &Ctx,
2546                           SourceLocation CallLoc,
2547                           const llvm::StringMap<bool> &CallerMap,
2548                           const llvm::StringMap<bool> &CalleeMap, QualType Ty,
2549                           bool IsArgument) {
2550   uint64_t Size = Ctx.getTypeSize(Ty);
2551   if (Size > 256)
2552     return checkAVXParamFeature(Diag, CallLoc, CallerMap, CalleeMap, Ty,
2553                                 "avx512f", IsArgument);
2554 
2555   if (Size > 128)
2556     return checkAVXParamFeature(Diag, CallLoc, CallerMap, CalleeMap, Ty, "avx",
2557                                 IsArgument);
2558 
2559   return false;
2560 }
2561 
checkFunctionCallABI(CodeGenModule & CGM,SourceLocation CallLoc,const FunctionDecl * Caller,const FunctionDecl * Callee,const CallArgList & Args) const2562 void X86_64TargetCodeGenInfo::checkFunctionCallABI(
2563     CodeGenModule &CGM, SourceLocation CallLoc, const FunctionDecl *Caller,
2564     const FunctionDecl *Callee, const CallArgList &Args) const {
2565   llvm::StringMap<bool> CallerMap;
2566   llvm::StringMap<bool> CalleeMap;
2567   unsigned ArgIndex = 0;
2568 
2569   // We need to loop through the actual call arguments rather than the the
2570   // function's parameters, in case this variadic.
2571   for (const CallArg &Arg : Args) {
2572     // The "avx" feature changes how vectors >128 in size are passed. "avx512f"
2573     // additionally changes how vectors >256 in size are passed. Like GCC, we
2574     // warn when a function is called with an argument where this will change.
2575     // Unlike GCC, we also error when it is an obvious ABI mismatch, that is,
2576     // the caller and callee features are mismatched.
2577     // Unfortunately, we cannot do this diagnostic in SEMA, since the callee can
2578     // change its ABI with attribute-target after this call.
2579     if (Arg.getType()->isVectorType() &&
2580         CGM.getContext().getTypeSize(Arg.getType()) > 128) {
2581       initFeatureMaps(CGM.getContext(), CallerMap, Caller, CalleeMap, Callee);
2582       QualType Ty = Arg.getType();
2583       // The CallArg seems to have desugared the type already, so for clearer
2584       // diagnostics, replace it with the type in the FunctionDecl if possible.
2585       if (ArgIndex < Callee->getNumParams())
2586         Ty = Callee->getParamDecl(ArgIndex)->getType();
2587 
2588       if (checkAVXParam(CGM.getDiags(), CGM.getContext(), CallLoc, CallerMap,
2589                         CalleeMap, Ty, /*IsArgument*/ true))
2590         return;
2591     }
2592     ++ArgIndex;
2593   }
2594 
2595   // Check return always, as we don't have a good way of knowing in codegen
2596   // whether this value is used, tail-called, etc.
2597   if (Callee->getReturnType()->isVectorType() &&
2598       CGM.getContext().getTypeSize(Callee->getReturnType()) > 128) {
2599     initFeatureMaps(CGM.getContext(), CallerMap, Caller, CalleeMap, Callee);
2600     checkAVXParam(CGM.getDiags(), CGM.getContext(), CallLoc, CallerMap,
2601                   CalleeMap, Callee->getReturnType(),
2602                   /*IsArgument*/ false);
2603   }
2604 }
2605 
qualifyWindowsLibrary(llvm::StringRef Lib)2606 static std::string qualifyWindowsLibrary(llvm::StringRef Lib) {
2607   // If the argument does not end in .lib, automatically add the suffix.
2608   // If the argument contains a space, enclose it in quotes.
2609   // This matches the behavior of MSVC.
2610   bool Quote = (Lib.find(' ') != StringRef::npos);
2611   std::string ArgStr = Quote ? "\"" : "";
2612   ArgStr += Lib;
2613   if (!Lib.endswith_insensitive(".lib") && !Lib.endswith_insensitive(".a"))
2614     ArgStr += ".lib";
2615   ArgStr += Quote ? "\"" : "";
2616   return ArgStr;
2617 }
2618 
2619 class WinX86_32TargetCodeGenInfo : public X86_32TargetCodeGenInfo {
2620 public:
WinX86_32TargetCodeGenInfo(CodeGen::CodeGenTypes & CGT,bool DarwinVectorABI,bool RetSmallStructInRegABI,bool Win32StructABI,unsigned NumRegisterParameters)2621   WinX86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
2622         bool DarwinVectorABI, bool RetSmallStructInRegABI, bool Win32StructABI,
2623         unsigned NumRegisterParameters)
2624     : X86_32TargetCodeGenInfo(CGT, DarwinVectorABI, RetSmallStructInRegABI,
2625         Win32StructABI, NumRegisterParameters, false) {}
2626 
2627   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
2628                            CodeGen::CodeGenModule &CGM) const override;
2629 
getDependentLibraryOption(llvm::StringRef Lib,llvm::SmallString<24> & Opt) const2630   void getDependentLibraryOption(llvm::StringRef Lib,
2631                                  llvm::SmallString<24> &Opt) const override {
2632     Opt = "/DEFAULTLIB:";
2633     Opt += qualifyWindowsLibrary(Lib);
2634   }
2635 
getDetectMismatchOption(llvm::StringRef Name,llvm::StringRef Value,llvm::SmallString<32> & Opt) const2636   void getDetectMismatchOption(llvm::StringRef Name,
2637                                llvm::StringRef Value,
2638                                llvm::SmallString<32> &Opt) const override {
2639     Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
2640   }
2641 };
2642 
addStackProbeTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & CGM)2643 static void addStackProbeTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
2644                                           CodeGen::CodeGenModule &CGM) {
2645   if (llvm::Function *Fn = dyn_cast_or_null<llvm::Function>(GV)) {
2646 
2647     if (CGM.getCodeGenOpts().StackProbeSize != 4096)
2648       Fn->addFnAttr("stack-probe-size",
2649                     llvm::utostr(CGM.getCodeGenOpts().StackProbeSize));
2650     if (CGM.getCodeGenOpts().NoStackArgProbe)
2651       Fn->addFnAttr("no-stack-arg-probe");
2652   }
2653 }
2654 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & CGM) const2655 void WinX86_32TargetCodeGenInfo::setTargetAttributes(
2656     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &CGM) const {
2657   X86_32TargetCodeGenInfo::setTargetAttributes(D, GV, CGM);
2658   if (GV->isDeclaration())
2659     return;
2660   addStackProbeTargetAttributes(D, GV, CGM);
2661 }
2662 
2663 class WinX86_64TargetCodeGenInfo : public TargetCodeGenInfo {
2664 public:
WinX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes & CGT,X86AVXABILevel AVXLevel)2665   WinX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
2666                              X86AVXABILevel AVXLevel)
2667       : TargetCodeGenInfo(std::make_unique<WinX86_64ABIInfo>(CGT, AVXLevel)) {}
2668 
2669   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
2670                            CodeGen::CodeGenModule &CGM) const override;
2671 
getDwarfEHStackPointer(CodeGen::CodeGenModule & CGM) const2672   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
2673     return 7;
2674   }
2675 
initDwarfEHRegSizeTable(CodeGen::CodeGenFunction & CGF,llvm::Value * Address) const2676   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
2677                                llvm::Value *Address) const override {
2678     llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
2679 
2680     // 0-15 are the 16 integer registers.
2681     // 16 is %rip.
2682     AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
2683     return false;
2684   }
2685 
getDependentLibraryOption(llvm::StringRef Lib,llvm::SmallString<24> & Opt) const2686   void getDependentLibraryOption(llvm::StringRef Lib,
2687                                  llvm::SmallString<24> &Opt) const override {
2688     Opt = "/DEFAULTLIB:";
2689     Opt += qualifyWindowsLibrary(Lib);
2690   }
2691 
getDetectMismatchOption(llvm::StringRef Name,llvm::StringRef Value,llvm::SmallString<32> & Opt) const2692   void getDetectMismatchOption(llvm::StringRef Name,
2693                                llvm::StringRef Value,
2694                                llvm::SmallString<32> &Opt) const override {
2695     Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
2696   }
2697 };
2698 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & CGM) const2699 void WinX86_64TargetCodeGenInfo::setTargetAttributes(
2700     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &CGM) const {
2701   TargetCodeGenInfo::setTargetAttributes(D, GV, CGM);
2702   if (GV->isDeclaration())
2703     return;
2704   if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D)) {
2705     if (FD->hasAttr<X86ForceAlignArgPointerAttr>()) {
2706       llvm::Function *Fn = cast<llvm::Function>(GV);
2707       Fn->addFnAttr("stackrealign");
2708     }
2709 
2710     addX86InterruptAttrs(FD, GV, CGM);
2711   }
2712 
2713   addStackProbeTargetAttributes(D, GV, CGM);
2714 }
2715 }
2716 
postMerge(unsigned AggregateSize,Class & Lo,Class & Hi) const2717 void X86_64ABIInfo::postMerge(unsigned AggregateSize, Class &Lo,
2718                               Class &Hi) const {
2719   // AMD64-ABI 3.2.3p2: Rule 5. Then a post merger cleanup is done:
2720   //
2721   // (a) If one of the classes is Memory, the whole argument is passed in
2722   //     memory.
2723   //
2724   // (b) If X87UP is not preceded by X87, the whole argument is passed in
2725   //     memory.
2726   //
2727   // (c) If the size of the aggregate exceeds two eightbytes and the first
2728   //     eightbyte isn't SSE or any other eightbyte isn't SSEUP, the whole
2729   //     argument is passed in memory. NOTE: This is necessary to keep the
2730   //     ABI working for processors that don't support the __m256 type.
2731   //
2732   // (d) If SSEUP is not preceded by SSE or SSEUP, it is converted to SSE.
2733   //
2734   // Some of these are enforced by the merging logic.  Others can arise
2735   // only with unions; for example:
2736   //   union { _Complex double; unsigned; }
2737   //
2738   // Note that clauses (b) and (c) were added in 0.98.
2739   //
2740   if (Hi == Memory)
2741     Lo = Memory;
2742   if (Hi == X87Up && Lo != X87 && honorsRevision0_98())
2743     Lo = Memory;
2744   if (AggregateSize > 128 && (Lo != SSE || Hi != SSEUp))
2745     Lo = Memory;
2746   if (Hi == SSEUp && Lo != SSE)
2747     Hi = SSE;
2748 }
2749 
merge(Class Accum,Class Field)2750 X86_64ABIInfo::Class X86_64ABIInfo::merge(Class Accum, Class Field) {
2751   // AMD64-ABI 3.2.3p2: Rule 4. Each field of an object is
2752   // classified recursively so that always two fields are
2753   // considered. The resulting class is calculated according to
2754   // the classes of the fields in the eightbyte:
2755   //
2756   // (a) If both classes are equal, this is the resulting class.
2757   //
2758   // (b) If one of the classes is NO_CLASS, the resulting class is
2759   // the other class.
2760   //
2761   // (c) If one of the classes is MEMORY, the result is the MEMORY
2762   // class.
2763   //
2764   // (d) If one of the classes is INTEGER, the result is the
2765   // INTEGER.
2766   //
2767   // (e) If one of the classes is X87, X87UP, COMPLEX_X87 class,
2768   // MEMORY is used as class.
2769   //
2770   // (f) Otherwise class SSE is used.
2771 
2772   // Accum should never be memory (we should have returned) or
2773   // ComplexX87 (because this cannot be passed in a structure).
2774   assert((Accum != Memory && Accum != ComplexX87) &&
2775          "Invalid accumulated classification during merge.");
2776   if (Accum == Field || Field == NoClass)
2777     return Accum;
2778   if (Field == Memory)
2779     return Memory;
2780   if (Accum == NoClass)
2781     return Field;
2782   if (Accum == Integer || Field == Integer)
2783     return Integer;
2784   if (Field == X87 || Field == X87Up || Field == ComplexX87 ||
2785       Accum == X87 || Accum == X87Up)
2786     return Memory;
2787   return SSE;
2788 }
2789 
classify(QualType Ty,uint64_t OffsetBase,Class & Lo,Class & Hi,bool isNamedArg) const2790 void X86_64ABIInfo::classify(QualType Ty, uint64_t OffsetBase,
2791                              Class &Lo, Class &Hi, bool isNamedArg) const {
2792   // FIXME: This code can be simplified by introducing a simple value class for
2793   // Class pairs with appropriate constructor methods for the various
2794   // situations.
2795 
2796   // FIXME: Some of the split computations are wrong; unaligned vectors
2797   // shouldn't be passed in registers for example, so there is no chance they
2798   // can straddle an eightbyte. Verify & simplify.
2799 
2800   Lo = Hi = NoClass;
2801 
2802   Class &Current = OffsetBase < 64 ? Lo : Hi;
2803   Current = Memory;
2804 
2805   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
2806     BuiltinType::Kind k = BT->getKind();
2807 
2808     if (k == BuiltinType::Void) {
2809       Current = NoClass;
2810     } else if (k == BuiltinType::Int128 || k == BuiltinType::UInt128) {
2811       Lo = Integer;
2812       Hi = Integer;
2813     } else if (k >= BuiltinType::Bool && k <= BuiltinType::LongLong) {
2814       Current = Integer;
2815     } else if (k == BuiltinType::Float || k == BuiltinType::Double) {
2816       Current = SSE;
2817     } else if (k == BuiltinType::LongDouble) {
2818       const llvm::fltSemantics *LDF = &getTarget().getLongDoubleFormat();
2819       if (LDF == &llvm::APFloat::IEEEquad()) {
2820         Lo = SSE;
2821         Hi = SSEUp;
2822       } else if (LDF == &llvm::APFloat::x87DoubleExtended()) {
2823         Lo = X87;
2824         Hi = X87Up;
2825       } else if (LDF == &llvm::APFloat::IEEEdouble()) {
2826         Current = SSE;
2827       } else
2828         llvm_unreachable("unexpected long double representation!");
2829     }
2830     // FIXME: _Decimal32 and _Decimal64 are SSE.
2831     // FIXME: _float128 and _Decimal128 are (SSE, SSEUp).
2832     return;
2833   }
2834 
2835   if (const EnumType *ET = Ty->getAs<EnumType>()) {
2836     // Classify the underlying integer type.
2837     classify(ET->getDecl()->getIntegerType(), OffsetBase, Lo, Hi, isNamedArg);
2838     return;
2839   }
2840 
2841   if (Ty->hasPointerRepresentation()) {
2842     Current = Integer;
2843     return;
2844   }
2845 
2846   if (Ty->isMemberPointerType()) {
2847     if (Ty->isMemberFunctionPointerType()) {
2848       if (Has64BitPointers) {
2849         // If Has64BitPointers, this is an {i64, i64}, so classify both
2850         // Lo and Hi now.
2851         Lo = Hi = Integer;
2852       } else {
2853         // Otherwise, with 32-bit pointers, this is an {i32, i32}. If that
2854         // straddles an eightbyte boundary, Hi should be classified as well.
2855         uint64_t EB_FuncPtr = (OffsetBase) / 64;
2856         uint64_t EB_ThisAdj = (OffsetBase + 64 - 1) / 64;
2857         if (EB_FuncPtr != EB_ThisAdj) {
2858           Lo = Hi = Integer;
2859         } else {
2860           Current = Integer;
2861         }
2862       }
2863     } else {
2864       Current = Integer;
2865     }
2866     return;
2867   }
2868 
2869   if (const VectorType *VT = Ty->getAs<VectorType>()) {
2870     uint64_t Size = getContext().getTypeSize(VT);
2871     if (Size == 1 || Size == 8 || Size == 16 || Size == 32) {
2872       // gcc passes the following as integer:
2873       // 4 bytes - <4 x char>, <2 x short>, <1 x int>, <1 x float>
2874       // 2 bytes - <2 x char>, <1 x short>
2875       // 1 byte  - <1 x char>
2876       Current = Integer;
2877 
2878       // If this type crosses an eightbyte boundary, it should be
2879       // split.
2880       uint64_t EB_Lo = (OffsetBase) / 64;
2881       uint64_t EB_Hi = (OffsetBase + Size - 1) / 64;
2882       if (EB_Lo != EB_Hi)
2883         Hi = Lo;
2884     } else if (Size == 64) {
2885       QualType ElementType = VT->getElementType();
2886 
2887       // gcc passes <1 x double> in memory. :(
2888       if (ElementType->isSpecificBuiltinType(BuiltinType::Double))
2889         return;
2890 
2891       // gcc passes <1 x long long> as SSE but clang used to unconditionally
2892       // pass them as integer.  For platforms where clang is the de facto
2893       // platform compiler, we must continue to use integer.
2894       if (!classifyIntegerMMXAsSSE() &&
2895           (ElementType->isSpecificBuiltinType(BuiltinType::LongLong) ||
2896            ElementType->isSpecificBuiltinType(BuiltinType::ULongLong) ||
2897            ElementType->isSpecificBuiltinType(BuiltinType::Long) ||
2898            ElementType->isSpecificBuiltinType(BuiltinType::ULong)))
2899         Current = Integer;
2900       else
2901         Current = SSE;
2902 
2903       // If this type crosses an eightbyte boundary, it should be
2904       // split.
2905       if (OffsetBase && OffsetBase != 64)
2906         Hi = Lo;
2907     } else if (Size == 128 ||
2908                (isNamedArg && Size <= getNativeVectorSizeForAVXABI(AVXLevel))) {
2909       QualType ElementType = VT->getElementType();
2910 
2911       // gcc passes 256 and 512 bit <X x __int128> vectors in memory. :(
2912       if (passInt128VectorsInMem() && Size != 128 &&
2913           (ElementType->isSpecificBuiltinType(BuiltinType::Int128) ||
2914            ElementType->isSpecificBuiltinType(BuiltinType::UInt128)))
2915         return;
2916 
2917       // Arguments of 256-bits are split into four eightbyte chunks. The
2918       // least significant one belongs to class SSE and all the others to class
2919       // SSEUP. The original Lo and Hi design considers that types can't be
2920       // greater than 128-bits, so a 64-bit split in Hi and Lo makes sense.
2921       // This design isn't correct for 256-bits, but since there're no cases
2922       // where the upper parts would need to be inspected, avoid adding
2923       // complexity and just consider Hi to match the 64-256 part.
2924       //
2925       // Note that per 3.5.7 of AMD64-ABI, 256-bit args are only passed in
2926       // registers if they are "named", i.e. not part of the "..." of a
2927       // variadic function.
2928       //
2929       // Similarly, per 3.2.3. of the AVX512 draft, 512-bits ("named") args are
2930       // split into eight eightbyte chunks, one SSE and seven SSEUP.
2931       Lo = SSE;
2932       Hi = SSEUp;
2933     }
2934     return;
2935   }
2936 
2937   if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
2938     QualType ET = getContext().getCanonicalType(CT->getElementType());
2939 
2940     uint64_t Size = getContext().getTypeSize(Ty);
2941     if (ET->isIntegralOrEnumerationType()) {
2942       if (Size <= 64)
2943         Current = Integer;
2944       else if (Size <= 128)
2945         Lo = Hi = Integer;
2946     } else if (ET == getContext().FloatTy) {
2947       Current = SSE;
2948     } else if (ET == getContext().DoubleTy) {
2949       Lo = Hi = SSE;
2950     } else if (ET == getContext().LongDoubleTy) {
2951       const llvm::fltSemantics *LDF = &getTarget().getLongDoubleFormat();
2952       if (LDF == &llvm::APFloat::IEEEquad())
2953         Current = Memory;
2954       else if (LDF == &llvm::APFloat::x87DoubleExtended())
2955         Current = ComplexX87;
2956       else if (LDF == &llvm::APFloat::IEEEdouble())
2957         Lo = Hi = SSE;
2958       else
2959         llvm_unreachable("unexpected long double representation!");
2960     }
2961 
2962     // If this complex type crosses an eightbyte boundary then it
2963     // should be split.
2964     uint64_t EB_Real = (OffsetBase) / 64;
2965     uint64_t EB_Imag = (OffsetBase + getContext().getTypeSize(ET)) / 64;
2966     if (Hi == NoClass && EB_Real != EB_Imag)
2967       Hi = Lo;
2968 
2969     return;
2970   }
2971 
2972   if (const auto *EITy = Ty->getAs<ExtIntType>()) {
2973     if (EITy->getNumBits() <= 64)
2974       Current = Integer;
2975     else if (EITy->getNumBits() <= 128)
2976       Lo = Hi = Integer;
2977     // Larger values need to get passed in memory.
2978     return;
2979   }
2980 
2981   if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) {
2982     // Arrays are treated like structures.
2983 
2984     uint64_t Size = getContext().getTypeSize(Ty);
2985 
2986     // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
2987     // than eight eightbytes, ..., it has class MEMORY.
2988     if (Size > 512)
2989       return;
2990 
2991     // AMD64-ABI 3.2.3p2: Rule 1. If ..., or it contains unaligned
2992     // fields, it has class MEMORY.
2993     //
2994     // Only need to check alignment of array base.
2995     if (OffsetBase % getContext().getTypeAlign(AT->getElementType()))
2996       return;
2997 
2998     // Otherwise implement simplified merge. We could be smarter about
2999     // this, but it isn't worth it and would be harder to verify.
3000     Current = NoClass;
3001     uint64_t EltSize = getContext().getTypeSize(AT->getElementType());
3002     uint64_t ArraySize = AT->getSize().getZExtValue();
3003 
3004     // The only case a 256-bit wide vector could be used is when the array
3005     // contains a single 256-bit element. Since Lo and Hi logic isn't extended
3006     // to work for sizes wider than 128, early check and fallback to memory.
3007     //
3008     if (Size > 128 &&
3009         (Size != EltSize || Size > getNativeVectorSizeForAVXABI(AVXLevel)))
3010       return;
3011 
3012     for (uint64_t i=0, Offset=OffsetBase; i<ArraySize; ++i, Offset += EltSize) {
3013       Class FieldLo, FieldHi;
3014       classify(AT->getElementType(), Offset, FieldLo, FieldHi, isNamedArg);
3015       Lo = merge(Lo, FieldLo);
3016       Hi = merge(Hi, FieldHi);
3017       if (Lo == Memory || Hi == Memory)
3018         break;
3019     }
3020 
3021     postMerge(Size, Lo, Hi);
3022     assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp array classification.");
3023     return;
3024   }
3025 
3026   if (const RecordType *RT = Ty->getAs<RecordType>()) {
3027     uint64_t Size = getContext().getTypeSize(Ty);
3028 
3029     // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
3030     // than eight eightbytes, ..., it has class MEMORY.
3031     if (Size > 512)
3032       return;
3033 
3034     // AMD64-ABI 3.2.3p2: Rule 2. If a C++ object has either a non-trivial
3035     // copy constructor or a non-trivial destructor, it is passed by invisible
3036     // reference.
3037     if (getRecordArgABI(RT, getCXXABI()))
3038       return;
3039 
3040     const RecordDecl *RD = RT->getDecl();
3041 
3042     // Assume variable sized types are passed in memory.
3043     if (RD->hasFlexibleArrayMember())
3044       return;
3045 
3046     const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
3047 
3048     // Reset Lo class, this will be recomputed.
3049     Current = NoClass;
3050 
3051     // If this is a C++ record, classify the bases first.
3052     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
3053       for (const auto &I : CXXRD->bases()) {
3054         assert(!I.isVirtual() && !I.getType()->isDependentType() &&
3055                "Unexpected base class!");
3056         const auto *Base =
3057             cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl());
3058 
3059         // Classify this field.
3060         //
3061         // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate exceeds a
3062         // single eightbyte, each is classified separately. Each eightbyte gets
3063         // initialized to class NO_CLASS.
3064         Class FieldLo, FieldHi;
3065         uint64_t Offset =
3066           OffsetBase + getContext().toBits(Layout.getBaseClassOffset(Base));
3067         classify(I.getType(), Offset, FieldLo, FieldHi, isNamedArg);
3068         Lo = merge(Lo, FieldLo);
3069         Hi = merge(Hi, FieldHi);
3070         if (Lo == Memory || Hi == Memory) {
3071           postMerge(Size, Lo, Hi);
3072           return;
3073         }
3074       }
3075     }
3076 
3077     // Classify the fields one at a time, merging the results.
3078     unsigned idx = 0;
3079     bool UseClang11Compat = getContext().getLangOpts().getClangABICompat() <=
3080                                 LangOptions::ClangABI::Ver11 ||
3081                             getContext().getTargetInfo().getTriple().isPS4();
3082     bool IsUnion = RT->isUnionType() && !UseClang11Compat;
3083 
3084     for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
3085            i != e; ++i, ++idx) {
3086       uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
3087       bool BitField = i->isBitField();
3088 
3089       // Ignore padding bit-fields.
3090       if (BitField && i->isUnnamedBitfield())
3091         continue;
3092 
3093       // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger than
3094       // eight eightbytes, or it contains unaligned fields, it has class MEMORY.
3095       //
3096       // The only case a 256-bit or a 512-bit wide vector could be used is when
3097       // the struct contains a single 256-bit or 512-bit element. Early check
3098       // and fallback to memory.
3099       //
3100       // FIXME: Extended the Lo and Hi logic properly to work for size wider
3101       // than 128.
3102       if (Size > 128 &&
3103           ((!IsUnion && Size != getContext().getTypeSize(i->getType())) ||
3104            Size > getNativeVectorSizeForAVXABI(AVXLevel))) {
3105         Lo = Memory;
3106         postMerge(Size, Lo, Hi);
3107         return;
3108       }
3109       // Note, skip this test for bit-fields, see below.
3110       if (!BitField && Offset % getContext().getTypeAlign(i->getType())) {
3111         Lo = Memory;
3112         postMerge(Size, Lo, Hi);
3113         return;
3114       }
3115 
3116       // Classify this field.
3117       //
3118       // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate
3119       // exceeds a single eightbyte, each is classified
3120       // separately. Each eightbyte gets initialized to class
3121       // NO_CLASS.
3122       Class FieldLo, FieldHi;
3123 
3124       // Bit-fields require special handling, they do not force the
3125       // structure to be passed in memory even if unaligned, and
3126       // therefore they can straddle an eightbyte.
3127       if (BitField) {
3128         assert(!i->isUnnamedBitfield());
3129         uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
3130         uint64_t Size = i->getBitWidthValue(getContext());
3131 
3132         uint64_t EB_Lo = Offset / 64;
3133         uint64_t EB_Hi = (Offset + Size - 1) / 64;
3134 
3135         if (EB_Lo) {
3136           assert(EB_Hi == EB_Lo && "Invalid classification, type > 16 bytes.");
3137           FieldLo = NoClass;
3138           FieldHi = Integer;
3139         } else {
3140           FieldLo = Integer;
3141           FieldHi = EB_Hi ? Integer : NoClass;
3142         }
3143       } else
3144         classify(i->getType(), Offset, FieldLo, FieldHi, isNamedArg);
3145       Lo = merge(Lo, FieldLo);
3146       Hi = merge(Hi, FieldHi);
3147       if (Lo == Memory || Hi == Memory)
3148         break;
3149     }
3150 
3151     postMerge(Size, Lo, Hi);
3152   }
3153 }
3154 
getIndirectReturnResult(QualType Ty) const3155 ABIArgInfo X86_64ABIInfo::getIndirectReturnResult(QualType Ty) const {
3156   // If this is a scalar LLVM value then assume LLVM will pass it in the right
3157   // place naturally.
3158   if (!isAggregateTypeForABI(Ty)) {
3159     // Treat an enum type as its underlying type.
3160     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
3161       Ty = EnumTy->getDecl()->getIntegerType();
3162 
3163     if (Ty->isExtIntType())
3164       return getNaturalAlignIndirect(Ty);
3165 
3166     return (isPromotableIntegerTypeForABI(Ty) ? ABIArgInfo::getExtend(Ty)
3167                                               : ABIArgInfo::getDirect());
3168   }
3169 
3170   return getNaturalAlignIndirect(Ty);
3171 }
3172 
IsIllegalVectorType(QualType Ty) const3173 bool X86_64ABIInfo::IsIllegalVectorType(QualType Ty) const {
3174   if (const VectorType *VecTy = Ty->getAs<VectorType>()) {
3175     uint64_t Size = getContext().getTypeSize(VecTy);
3176     unsigned LargestVector = getNativeVectorSizeForAVXABI(AVXLevel);
3177     if (Size <= 64 || Size > LargestVector)
3178       return true;
3179     QualType EltTy = VecTy->getElementType();
3180     if (passInt128VectorsInMem() &&
3181         (EltTy->isSpecificBuiltinType(BuiltinType::Int128) ||
3182          EltTy->isSpecificBuiltinType(BuiltinType::UInt128)))
3183       return true;
3184   }
3185 
3186   return false;
3187 }
3188 
getIndirectResult(QualType Ty,unsigned freeIntRegs) const3189 ABIArgInfo X86_64ABIInfo::getIndirectResult(QualType Ty,
3190                                             unsigned freeIntRegs) const {
3191   // If this is a scalar LLVM value then assume LLVM will pass it in the right
3192   // place naturally.
3193   //
3194   // This assumption is optimistic, as there could be free registers available
3195   // when we need to pass this argument in memory, and LLVM could try to pass
3196   // the argument in the free register. This does not seem to happen currently,
3197   // but this code would be much safer if we could mark the argument with
3198   // 'onstack'. See PR12193.
3199   if (!isAggregateTypeForABI(Ty) && !IsIllegalVectorType(Ty) &&
3200       !Ty->isExtIntType()) {
3201     // Treat an enum type as its underlying type.
3202     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
3203       Ty = EnumTy->getDecl()->getIntegerType();
3204 
3205     return (isPromotableIntegerTypeForABI(Ty) ? ABIArgInfo::getExtend(Ty)
3206                                               : ABIArgInfo::getDirect());
3207   }
3208 
3209   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
3210     return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
3211 
3212   // Compute the byval alignment. We specify the alignment of the byval in all
3213   // cases so that the mid-level optimizer knows the alignment of the byval.
3214   unsigned Align = std::max(getContext().getTypeAlign(Ty) / 8, 8U);
3215 
3216   // Attempt to avoid passing indirect results using byval when possible. This
3217   // is important for good codegen.
3218   //
3219   // We do this by coercing the value into a scalar type which the backend can
3220   // handle naturally (i.e., without using byval).
3221   //
3222   // For simplicity, we currently only do this when we have exhausted all of the
3223   // free integer registers. Doing this when there are free integer registers
3224   // would require more care, as we would have to ensure that the coerced value
3225   // did not claim the unused register. That would require either reording the
3226   // arguments to the function (so that any subsequent inreg values came first),
3227   // or only doing this optimization when there were no following arguments that
3228   // might be inreg.
3229   //
3230   // We currently expect it to be rare (particularly in well written code) for
3231   // arguments to be passed on the stack when there are still free integer
3232   // registers available (this would typically imply large structs being passed
3233   // by value), so this seems like a fair tradeoff for now.
3234   //
3235   // We can revisit this if the backend grows support for 'onstack' parameter
3236   // attributes. See PR12193.
3237   if (freeIntRegs == 0) {
3238     uint64_t Size = getContext().getTypeSize(Ty);
3239 
3240     // If this type fits in an eightbyte, coerce it into the matching integral
3241     // type, which will end up on the stack (with alignment 8).
3242     if (Align == 8 && Size <= 64)
3243       return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
3244                                                           Size));
3245   }
3246 
3247   return ABIArgInfo::getIndirect(CharUnits::fromQuantity(Align));
3248 }
3249 
3250 /// The ABI specifies that a value should be passed in a full vector XMM/YMM
3251 /// register. Pick an LLVM IR type that will be passed as a vector register.
GetByteVectorType(QualType Ty) const3252 llvm::Type *X86_64ABIInfo::GetByteVectorType(QualType Ty) const {
3253   // Wrapper structs/arrays that only contain vectors are passed just like
3254   // vectors; strip them off if present.
3255   if (const Type *InnerTy = isSingleElementStruct(Ty, getContext()))
3256     Ty = QualType(InnerTy, 0);
3257 
3258   llvm::Type *IRType = CGT.ConvertType(Ty);
3259   if (isa<llvm::VectorType>(IRType)) {
3260     // Don't pass vXi128 vectors in their native type, the backend can't
3261     // legalize them.
3262     if (passInt128VectorsInMem() &&
3263         cast<llvm::VectorType>(IRType)->getElementType()->isIntegerTy(128)) {
3264       // Use a vXi64 vector.
3265       uint64_t Size = getContext().getTypeSize(Ty);
3266       return llvm::FixedVectorType::get(llvm::Type::getInt64Ty(getVMContext()),
3267                                         Size / 64);
3268     }
3269 
3270     return IRType;
3271   }
3272 
3273   if (IRType->getTypeID() == llvm::Type::FP128TyID)
3274     return IRType;
3275 
3276   // We couldn't find the preferred IR vector type for 'Ty'.
3277   uint64_t Size = getContext().getTypeSize(Ty);
3278   assert((Size == 128 || Size == 256 || Size == 512) && "Invalid type found!");
3279 
3280 
3281   // Return a LLVM IR vector type based on the size of 'Ty'.
3282   return llvm::FixedVectorType::get(llvm::Type::getDoubleTy(getVMContext()),
3283                                     Size / 64);
3284 }
3285 
3286 /// BitsContainNoUserData - Return true if the specified [start,end) bit range
3287 /// is known to either be off the end of the specified type or being in
3288 /// alignment padding.  The user type specified is known to be at most 128 bits
3289 /// in size, and have passed through X86_64ABIInfo::classify with a successful
3290 /// classification that put one of the two halves in the INTEGER class.
3291 ///
3292 /// It is conservatively correct to return false.
BitsContainNoUserData(QualType Ty,unsigned StartBit,unsigned EndBit,ASTContext & Context)3293 static bool BitsContainNoUserData(QualType Ty, unsigned StartBit,
3294                                   unsigned EndBit, ASTContext &Context) {
3295   // If the bytes being queried are off the end of the type, there is no user
3296   // data hiding here.  This handles analysis of builtins, vectors and other
3297   // types that don't contain interesting padding.
3298   unsigned TySize = (unsigned)Context.getTypeSize(Ty);
3299   if (TySize <= StartBit)
3300     return true;
3301 
3302   if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
3303     unsigned EltSize = (unsigned)Context.getTypeSize(AT->getElementType());
3304     unsigned NumElts = (unsigned)AT->getSize().getZExtValue();
3305 
3306     // Check each element to see if the element overlaps with the queried range.
3307     for (unsigned i = 0; i != NumElts; ++i) {
3308       // If the element is after the span we care about, then we're done..
3309       unsigned EltOffset = i*EltSize;
3310       if (EltOffset >= EndBit) break;
3311 
3312       unsigned EltStart = EltOffset < StartBit ? StartBit-EltOffset :0;
3313       if (!BitsContainNoUserData(AT->getElementType(), EltStart,
3314                                  EndBit-EltOffset, Context))
3315         return false;
3316     }
3317     // If it overlaps no elements, then it is safe to process as padding.
3318     return true;
3319   }
3320 
3321   if (const RecordType *RT = Ty->getAs<RecordType>()) {
3322     const RecordDecl *RD = RT->getDecl();
3323     const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
3324 
3325     // If this is a C++ record, check the bases first.
3326     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
3327       for (const auto &I : CXXRD->bases()) {
3328         assert(!I.isVirtual() && !I.getType()->isDependentType() &&
3329                "Unexpected base class!");
3330         const auto *Base =
3331             cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl());
3332 
3333         // If the base is after the span we care about, ignore it.
3334         unsigned BaseOffset = Context.toBits(Layout.getBaseClassOffset(Base));
3335         if (BaseOffset >= EndBit) continue;
3336 
3337         unsigned BaseStart = BaseOffset < StartBit ? StartBit-BaseOffset :0;
3338         if (!BitsContainNoUserData(I.getType(), BaseStart,
3339                                    EndBit-BaseOffset, Context))
3340           return false;
3341       }
3342     }
3343 
3344     // Verify that no field has data that overlaps the region of interest.  Yes
3345     // this could be sped up a lot by being smarter about queried fields,
3346     // however we're only looking at structs up to 16 bytes, so we don't care
3347     // much.
3348     unsigned idx = 0;
3349     for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
3350          i != e; ++i, ++idx) {
3351       unsigned FieldOffset = (unsigned)Layout.getFieldOffset(idx);
3352 
3353       // If we found a field after the region we care about, then we're done.
3354       if (FieldOffset >= EndBit) break;
3355 
3356       unsigned FieldStart = FieldOffset < StartBit ? StartBit-FieldOffset :0;
3357       if (!BitsContainNoUserData(i->getType(), FieldStart, EndBit-FieldOffset,
3358                                  Context))
3359         return false;
3360     }
3361 
3362     // If nothing in this record overlapped the area of interest, then we're
3363     // clean.
3364     return true;
3365   }
3366 
3367   return false;
3368 }
3369 
3370 /// ContainsFloatAtOffset - Return true if the specified LLVM IR type has a
3371 /// float member at the specified offset.  For example, {int,{float}} has a
3372 /// float at offset 4.  It is conservatively correct for this routine to return
3373 /// false.
ContainsFloatAtOffset(llvm::Type * IRType,unsigned IROffset,const llvm::DataLayout & TD)3374 static bool ContainsFloatAtOffset(llvm::Type *IRType, unsigned IROffset,
3375                                   const llvm::DataLayout &TD) {
3376   // Base case if we find a float.
3377   if (IROffset == 0 && IRType->isFloatTy())
3378     return true;
3379 
3380   // If this is a struct, recurse into the field at the specified offset.
3381   if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
3382     const llvm::StructLayout *SL = TD.getStructLayout(STy);
3383     unsigned Elt = SL->getElementContainingOffset(IROffset);
3384     IROffset -= SL->getElementOffset(Elt);
3385     return ContainsFloatAtOffset(STy->getElementType(Elt), IROffset, TD);
3386   }
3387 
3388   // If this is an array, recurse into the field at the specified offset.
3389   if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
3390     llvm::Type *EltTy = ATy->getElementType();
3391     unsigned EltSize = TD.getTypeAllocSize(EltTy);
3392     IROffset -= IROffset/EltSize*EltSize;
3393     return ContainsFloatAtOffset(EltTy, IROffset, TD);
3394   }
3395 
3396   return false;
3397 }
3398 
3399 
3400 /// GetSSETypeAtOffset - Return a type that will be passed by the backend in the
3401 /// low 8 bytes of an XMM register, corresponding to the SSE class.
3402 llvm::Type *X86_64ABIInfo::
GetSSETypeAtOffset(llvm::Type * IRType,unsigned IROffset,QualType SourceTy,unsigned SourceOffset) const3403 GetSSETypeAtOffset(llvm::Type *IRType, unsigned IROffset,
3404                    QualType SourceTy, unsigned SourceOffset) const {
3405   // The only three choices we have are either double, <2 x float>, or float. We
3406   // pass as float if the last 4 bytes is just padding.  This happens for
3407   // structs that contain 3 floats.
3408   if (BitsContainNoUserData(SourceTy, SourceOffset*8+32,
3409                             SourceOffset*8+64, getContext()))
3410     return llvm::Type::getFloatTy(getVMContext());
3411 
3412   // We want to pass as <2 x float> if the LLVM IR type contains a float at
3413   // offset+0 and offset+4.  Walk the LLVM IR type to find out if this is the
3414   // case.
3415   if (ContainsFloatAtOffset(IRType, IROffset, getDataLayout()) &&
3416       ContainsFloatAtOffset(IRType, IROffset+4, getDataLayout()))
3417     return llvm::FixedVectorType::get(llvm::Type::getFloatTy(getVMContext()),
3418                                       2);
3419 
3420   return llvm::Type::getDoubleTy(getVMContext());
3421 }
3422 
3423 
3424 /// GetINTEGERTypeAtOffset - The ABI specifies that a value should be passed in
3425 /// an 8-byte GPR.  This means that we either have a scalar or we are talking
3426 /// about the high or low part of an up-to-16-byte struct.  This routine picks
3427 /// the best LLVM IR type to represent this, which may be i64 or may be anything
3428 /// else that the backend will pass in a GPR that works better (e.g. i8, %foo*,
3429 /// etc).
3430 ///
3431 /// PrefType is an LLVM IR type that corresponds to (part of) the IR type for
3432 /// the source type.  IROffset is an offset in bytes into the LLVM IR type that
3433 /// the 8-byte value references.  PrefType may be null.
3434 ///
3435 /// SourceTy is the source-level type for the entire argument.  SourceOffset is
3436 /// an offset into this that we're processing (which is always either 0 or 8).
3437 ///
3438 llvm::Type *X86_64ABIInfo::
GetINTEGERTypeAtOffset(llvm::Type * IRType,unsigned IROffset,QualType SourceTy,unsigned SourceOffset) const3439 GetINTEGERTypeAtOffset(llvm::Type *IRType, unsigned IROffset,
3440                        QualType SourceTy, unsigned SourceOffset) const {
3441   // If we're dealing with an un-offset LLVM IR type, then it means that we're
3442   // returning an 8-byte unit starting with it.  See if we can safely use it.
3443   if (IROffset == 0) {
3444     // Pointers and int64's always fill the 8-byte unit.
3445     if ((isa<llvm::PointerType>(IRType) && Has64BitPointers) ||
3446         IRType->isIntegerTy(64))
3447       return IRType;
3448 
3449     // If we have a 1/2/4-byte integer, we can use it only if the rest of the
3450     // goodness in the source type is just tail padding.  This is allowed to
3451     // kick in for struct {double,int} on the int, but not on
3452     // struct{double,int,int} because we wouldn't return the second int.  We
3453     // have to do this analysis on the source type because we can't depend on
3454     // unions being lowered a specific way etc.
3455     if (IRType->isIntegerTy(8) || IRType->isIntegerTy(16) ||
3456         IRType->isIntegerTy(32) ||
3457         (isa<llvm::PointerType>(IRType) && !Has64BitPointers)) {
3458       unsigned BitWidth = isa<llvm::PointerType>(IRType) ? 32 :
3459           cast<llvm::IntegerType>(IRType)->getBitWidth();
3460 
3461       if (BitsContainNoUserData(SourceTy, SourceOffset*8+BitWidth,
3462                                 SourceOffset*8+64, getContext()))
3463         return IRType;
3464     }
3465   }
3466 
3467   if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
3468     // If this is a struct, recurse into the field at the specified offset.
3469     const llvm::StructLayout *SL = getDataLayout().getStructLayout(STy);
3470     if (IROffset < SL->getSizeInBytes()) {
3471       unsigned FieldIdx = SL->getElementContainingOffset(IROffset);
3472       IROffset -= SL->getElementOffset(FieldIdx);
3473 
3474       return GetINTEGERTypeAtOffset(STy->getElementType(FieldIdx), IROffset,
3475                                     SourceTy, SourceOffset);
3476     }
3477   }
3478 
3479   if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
3480     llvm::Type *EltTy = ATy->getElementType();
3481     unsigned EltSize = getDataLayout().getTypeAllocSize(EltTy);
3482     unsigned EltOffset = IROffset/EltSize*EltSize;
3483     return GetINTEGERTypeAtOffset(EltTy, IROffset-EltOffset, SourceTy,
3484                                   SourceOffset);
3485   }
3486 
3487   // Okay, we don't have any better idea of what to pass, so we pass this in an
3488   // integer register that isn't too big to fit the rest of the struct.
3489   unsigned TySizeInBytes =
3490     (unsigned)getContext().getTypeSizeInChars(SourceTy).getQuantity();
3491 
3492   assert(TySizeInBytes != SourceOffset && "Empty field?");
3493 
3494   // It is always safe to classify this as an integer type up to i64 that
3495   // isn't larger than the structure.
3496   return llvm::IntegerType::get(getVMContext(),
3497                                 std::min(TySizeInBytes-SourceOffset, 8U)*8);
3498 }
3499 
3500 
3501 /// GetX86_64ByValArgumentPair - Given a high and low type that can ideally
3502 /// be used as elements of a two register pair to pass or return, return a
3503 /// first class aggregate to represent them.  For example, if the low part of
3504 /// a by-value argument should be passed as i32* and the high part as float,
3505 /// return {i32*, float}.
3506 static llvm::Type *
GetX86_64ByValArgumentPair(llvm::Type * Lo,llvm::Type * Hi,const llvm::DataLayout & TD)3507 GetX86_64ByValArgumentPair(llvm::Type *Lo, llvm::Type *Hi,
3508                            const llvm::DataLayout &TD) {
3509   // In order to correctly satisfy the ABI, we need to the high part to start
3510   // at offset 8.  If the high and low parts we inferred are both 4-byte types
3511   // (e.g. i32 and i32) then the resultant struct type ({i32,i32}) won't have
3512   // the second element at offset 8.  Check for this:
3513   unsigned LoSize = (unsigned)TD.getTypeAllocSize(Lo);
3514   unsigned HiAlign = TD.getABITypeAlignment(Hi);
3515   unsigned HiStart = llvm::alignTo(LoSize, HiAlign);
3516   assert(HiStart != 0 && HiStart <= 8 && "Invalid x86-64 argument pair!");
3517 
3518   // To handle this, we have to increase the size of the low part so that the
3519   // second element will start at an 8 byte offset.  We can't increase the size
3520   // of the second element because it might make us access off the end of the
3521   // struct.
3522   if (HiStart != 8) {
3523     // There are usually two sorts of types the ABI generation code can produce
3524     // for the low part of a pair that aren't 8 bytes in size: float or
3525     // i8/i16/i32.  This can also include pointers when they are 32-bit (X32 and
3526     // NaCl).
3527     // Promote these to a larger type.
3528     if (Lo->isFloatTy())
3529       Lo = llvm::Type::getDoubleTy(Lo->getContext());
3530     else {
3531       assert((Lo->isIntegerTy() || Lo->isPointerTy())
3532              && "Invalid/unknown lo type");
3533       Lo = llvm::Type::getInt64Ty(Lo->getContext());
3534     }
3535   }
3536 
3537   llvm::StructType *Result = llvm::StructType::get(Lo, Hi);
3538 
3539   // Verify that the second element is at an 8-byte offset.
3540   assert(TD.getStructLayout(Result)->getElementOffset(1) == 8 &&
3541          "Invalid x86-64 argument pair!");
3542   return Result;
3543 }
3544 
3545 ABIArgInfo X86_64ABIInfo::
classifyReturnType(QualType RetTy) const3546 classifyReturnType(QualType RetTy) const {
3547   // AMD64-ABI 3.2.3p4: Rule 1. Classify the return type with the
3548   // classification algorithm.
3549   X86_64ABIInfo::Class Lo, Hi;
3550   classify(RetTy, 0, Lo, Hi, /*isNamedArg*/ true);
3551 
3552   // Check some invariants.
3553   assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
3554   assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
3555 
3556   llvm::Type *ResType = nullptr;
3557   switch (Lo) {
3558   case NoClass:
3559     if (Hi == NoClass)
3560       return ABIArgInfo::getIgnore();
3561     // If the low part is just padding, it takes no register, leave ResType
3562     // null.
3563     assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
3564            "Unknown missing lo part");
3565     break;
3566 
3567   case SSEUp:
3568   case X87Up:
3569     llvm_unreachable("Invalid classification for lo word.");
3570 
3571     // AMD64-ABI 3.2.3p4: Rule 2. Types of class memory are returned via
3572     // hidden argument.
3573   case Memory:
3574     return getIndirectReturnResult(RetTy);
3575 
3576     // AMD64-ABI 3.2.3p4: Rule 3. If the class is INTEGER, the next
3577     // available register of the sequence %rax, %rdx is used.
3578   case Integer:
3579     ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
3580 
3581     // If we have a sign or zero extended integer, make sure to return Extend
3582     // so that the parameter gets the right LLVM IR attributes.
3583     if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
3584       // Treat an enum type as its underlying type.
3585       if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
3586         RetTy = EnumTy->getDecl()->getIntegerType();
3587 
3588       if (RetTy->isIntegralOrEnumerationType() &&
3589           isPromotableIntegerTypeForABI(RetTy))
3590         return ABIArgInfo::getExtend(RetTy);
3591     }
3592     break;
3593 
3594     // AMD64-ABI 3.2.3p4: Rule 4. If the class is SSE, the next
3595     // available SSE register of the sequence %xmm0, %xmm1 is used.
3596   case SSE:
3597     ResType = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
3598     break;
3599 
3600     // AMD64-ABI 3.2.3p4: Rule 6. If the class is X87, the value is
3601     // returned on the X87 stack in %st0 as 80-bit x87 number.
3602   case X87:
3603     ResType = llvm::Type::getX86_FP80Ty(getVMContext());
3604     break;
3605 
3606     // AMD64-ABI 3.2.3p4: Rule 8. If the class is COMPLEX_X87, the real
3607     // part of the value is returned in %st0 and the imaginary part in
3608     // %st1.
3609   case ComplexX87:
3610     assert(Hi == ComplexX87 && "Unexpected ComplexX87 classification.");
3611     ResType = llvm::StructType::get(llvm::Type::getX86_FP80Ty(getVMContext()),
3612                                     llvm::Type::getX86_FP80Ty(getVMContext()));
3613     break;
3614   }
3615 
3616   llvm::Type *HighPart = nullptr;
3617   switch (Hi) {
3618     // Memory was handled previously and X87 should
3619     // never occur as a hi class.
3620   case Memory:
3621   case X87:
3622     llvm_unreachable("Invalid classification for hi word.");
3623 
3624   case ComplexX87: // Previously handled.
3625   case NoClass:
3626     break;
3627 
3628   case Integer:
3629     HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
3630     if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
3631       return ABIArgInfo::getDirect(HighPart, 8);
3632     break;
3633   case SSE:
3634     HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
3635     if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
3636       return ABIArgInfo::getDirect(HighPart, 8);
3637     break;
3638 
3639     // AMD64-ABI 3.2.3p4: Rule 5. If the class is SSEUP, the eightbyte
3640     // is passed in the next available eightbyte chunk if the last used
3641     // vector register.
3642     //
3643     // SSEUP should always be preceded by SSE, just widen.
3644   case SSEUp:
3645     assert(Lo == SSE && "Unexpected SSEUp classification.");
3646     ResType = GetByteVectorType(RetTy);
3647     break;
3648 
3649     // AMD64-ABI 3.2.3p4: Rule 7. If the class is X87UP, the value is
3650     // returned together with the previous X87 value in %st0.
3651   case X87Up:
3652     // If X87Up is preceded by X87, we don't need to do
3653     // anything. However, in some cases with unions it may not be
3654     // preceded by X87. In such situations we follow gcc and pass the
3655     // extra bits in an SSE reg.
3656     if (Lo != X87) {
3657       HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
3658       if (Lo == NoClass)  // Return HighPart at offset 8 in memory.
3659         return ABIArgInfo::getDirect(HighPart, 8);
3660     }
3661     break;
3662   }
3663 
3664   // If a high part was specified, merge it together with the low part.  It is
3665   // known to pass in the high eightbyte of the result.  We do this by forming a
3666   // first class struct aggregate with the high and low part: {low, high}
3667   if (HighPart)
3668     ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getDataLayout());
3669 
3670   return ABIArgInfo::getDirect(ResType);
3671 }
3672 
classifyArgumentType(QualType Ty,unsigned freeIntRegs,unsigned & neededInt,unsigned & neededSSE,bool isNamedArg) const3673 ABIArgInfo X86_64ABIInfo::classifyArgumentType(
3674   QualType Ty, unsigned freeIntRegs, unsigned &neededInt, unsigned &neededSSE,
3675   bool isNamedArg)
3676   const
3677 {
3678   Ty = useFirstFieldIfTransparentUnion(Ty);
3679 
3680   X86_64ABIInfo::Class Lo, Hi;
3681   classify(Ty, 0, Lo, Hi, isNamedArg);
3682 
3683   // Check some invariants.
3684   // FIXME: Enforce these by construction.
3685   assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
3686   assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
3687 
3688   neededInt = 0;
3689   neededSSE = 0;
3690   llvm::Type *ResType = nullptr;
3691   switch (Lo) {
3692   case NoClass:
3693     if (Hi == NoClass)
3694       return ABIArgInfo::getIgnore();
3695     // If the low part is just padding, it takes no register, leave ResType
3696     // null.
3697     assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
3698            "Unknown missing lo part");
3699     break;
3700 
3701     // AMD64-ABI 3.2.3p3: Rule 1. If the class is MEMORY, pass the argument
3702     // on the stack.
3703   case Memory:
3704 
3705     // AMD64-ABI 3.2.3p3: Rule 5. If the class is X87, X87UP or
3706     // COMPLEX_X87, it is passed in memory.
3707   case X87:
3708   case ComplexX87:
3709     if (getRecordArgABI(Ty, getCXXABI()) == CGCXXABI::RAA_Indirect)
3710       ++neededInt;
3711     return getIndirectResult(Ty, freeIntRegs);
3712 
3713   case SSEUp:
3714   case X87Up:
3715     llvm_unreachable("Invalid classification for lo word.");
3716 
3717     // AMD64-ABI 3.2.3p3: Rule 2. If the class is INTEGER, the next
3718     // available register of the sequence %rdi, %rsi, %rdx, %rcx, %r8
3719     // and %r9 is used.
3720   case Integer:
3721     ++neededInt;
3722 
3723     // Pick an 8-byte type based on the preferred type.
3724     ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 0, Ty, 0);
3725 
3726     // If we have a sign or zero extended integer, make sure to return Extend
3727     // so that the parameter gets the right LLVM IR attributes.
3728     if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
3729       // Treat an enum type as its underlying type.
3730       if (const EnumType *EnumTy = Ty->getAs<EnumType>())
3731         Ty = EnumTy->getDecl()->getIntegerType();
3732 
3733       if (Ty->isIntegralOrEnumerationType() &&
3734           isPromotableIntegerTypeForABI(Ty))
3735         return ABIArgInfo::getExtend(Ty);
3736     }
3737 
3738     break;
3739 
3740     // AMD64-ABI 3.2.3p3: Rule 3. If the class is SSE, the next
3741     // available SSE register is used, the registers are taken in the
3742     // order from %xmm0 to %xmm7.
3743   case SSE: {
3744     llvm::Type *IRType = CGT.ConvertType(Ty);
3745     ResType = GetSSETypeAtOffset(IRType, 0, Ty, 0);
3746     ++neededSSE;
3747     break;
3748   }
3749   }
3750 
3751   llvm::Type *HighPart = nullptr;
3752   switch (Hi) {
3753     // Memory was handled previously, ComplexX87 and X87 should
3754     // never occur as hi classes, and X87Up must be preceded by X87,
3755     // which is passed in memory.
3756   case Memory:
3757   case X87:
3758   case ComplexX87:
3759     llvm_unreachable("Invalid classification for hi word.");
3760 
3761   case NoClass: break;
3762 
3763   case Integer:
3764     ++neededInt;
3765     // Pick an 8-byte type based on the preferred type.
3766     HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
3767 
3768     if (Lo == NoClass)  // Pass HighPart at offset 8 in memory.
3769       return ABIArgInfo::getDirect(HighPart, 8);
3770     break;
3771 
3772     // X87Up generally doesn't occur here (long double is passed in
3773     // memory), except in situations involving unions.
3774   case X87Up:
3775   case SSE:
3776     HighPart = GetSSETypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
3777 
3778     if (Lo == NoClass)  // Pass HighPart at offset 8 in memory.
3779       return ABIArgInfo::getDirect(HighPart, 8);
3780 
3781     ++neededSSE;
3782     break;
3783 
3784     // AMD64-ABI 3.2.3p3: Rule 4. If the class is SSEUP, the
3785     // eightbyte is passed in the upper half of the last used SSE
3786     // register.  This only happens when 128-bit vectors are passed.
3787   case SSEUp:
3788     assert(Lo == SSE && "Unexpected SSEUp classification");
3789     ResType = GetByteVectorType(Ty);
3790     break;
3791   }
3792 
3793   // If a high part was specified, merge it together with the low part.  It is
3794   // known to pass in the high eightbyte of the result.  We do this by forming a
3795   // first class struct aggregate with the high and low part: {low, high}
3796   if (HighPart)
3797     ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getDataLayout());
3798 
3799   return ABIArgInfo::getDirect(ResType);
3800 }
3801 
3802 ABIArgInfo
classifyRegCallStructTypeImpl(QualType Ty,unsigned & NeededInt,unsigned & NeededSSE) const3803 X86_64ABIInfo::classifyRegCallStructTypeImpl(QualType Ty, unsigned &NeededInt,
3804                                              unsigned &NeededSSE) const {
3805   auto RT = Ty->getAs<RecordType>();
3806   assert(RT && "classifyRegCallStructType only valid with struct types");
3807 
3808   if (RT->getDecl()->hasFlexibleArrayMember())
3809     return getIndirectReturnResult(Ty);
3810 
3811   // Sum up bases
3812   if (auto CXXRD = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
3813     if (CXXRD->isDynamicClass()) {
3814       NeededInt = NeededSSE = 0;
3815       return getIndirectReturnResult(Ty);
3816     }
3817 
3818     for (const auto &I : CXXRD->bases())
3819       if (classifyRegCallStructTypeImpl(I.getType(), NeededInt, NeededSSE)
3820               .isIndirect()) {
3821         NeededInt = NeededSSE = 0;
3822         return getIndirectReturnResult(Ty);
3823       }
3824   }
3825 
3826   // Sum up members
3827   for (const auto *FD : RT->getDecl()->fields()) {
3828     if (FD->getType()->isRecordType() && !FD->getType()->isUnionType()) {
3829       if (classifyRegCallStructTypeImpl(FD->getType(), NeededInt, NeededSSE)
3830               .isIndirect()) {
3831         NeededInt = NeededSSE = 0;
3832         return getIndirectReturnResult(Ty);
3833       }
3834     } else {
3835       unsigned LocalNeededInt, LocalNeededSSE;
3836       if (classifyArgumentType(FD->getType(), UINT_MAX, LocalNeededInt,
3837                                LocalNeededSSE, true)
3838               .isIndirect()) {
3839         NeededInt = NeededSSE = 0;
3840         return getIndirectReturnResult(Ty);
3841       }
3842       NeededInt += LocalNeededInt;
3843       NeededSSE += LocalNeededSSE;
3844     }
3845   }
3846 
3847   return ABIArgInfo::getDirect();
3848 }
3849 
classifyRegCallStructType(QualType Ty,unsigned & NeededInt,unsigned & NeededSSE) const3850 ABIArgInfo X86_64ABIInfo::classifyRegCallStructType(QualType Ty,
3851                                                     unsigned &NeededInt,
3852                                                     unsigned &NeededSSE) const {
3853 
3854   NeededInt = 0;
3855   NeededSSE = 0;
3856 
3857   return classifyRegCallStructTypeImpl(Ty, NeededInt, NeededSSE);
3858 }
3859 
computeInfo(CGFunctionInfo & FI) const3860 void X86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
3861 
3862   const unsigned CallingConv = FI.getCallingConvention();
3863   // It is possible to force Win64 calling convention on any x86_64 target by
3864   // using __attribute__((ms_abi)). In such case to correctly emit Win64
3865   // compatible code delegate this call to WinX86_64ABIInfo::computeInfo.
3866   if (CallingConv == llvm::CallingConv::Win64) {
3867     WinX86_64ABIInfo Win64ABIInfo(CGT, AVXLevel);
3868     Win64ABIInfo.computeInfo(FI);
3869     return;
3870   }
3871 
3872   bool IsRegCall = CallingConv == llvm::CallingConv::X86_RegCall;
3873 
3874   // Keep track of the number of assigned registers.
3875   unsigned FreeIntRegs = IsRegCall ? 11 : 6;
3876   unsigned FreeSSERegs = IsRegCall ? 16 : 8;
3877   unsigned NeededInt, NeededSSE;
3878 
3879   if (!::classifyReturnType(getCXXABI(), FI, *this)) {
3880     if (IsRegCall && FI.getReturnType()->getTypePtr()->isRecordType() &&
3881         !FI.getReturnType()->getTypePtr()->isUnionType()) {
3882       FI.getReturnInfo() =
3883           classifyRegCallStructType(FI.getReturnType(), NeededInt, NeededSSE);
3884       if (FreeIntRegs >= NeededInt && FreeSSERegs >= NeededSSE) {
3885         FreeIntRegs -= NeededInt;
3886         FreeSSERegs -= NeededSSE;
3887       } else {
3888         FI.getReturnInfo() = getIndirectReturnResult(FI.getReturnType());
3889       }
3890     } else if (IsRegCall && FI.getReturnType()->getAs<ComplexType>() &&
3891                getContext().getCanonicalType(FI.getReturnType()
3892                                                  ->getAs<ComplexType>()
3893                                                  ->getElementType()) ==
3894                    getContext().LongDoubleTy)
3895       // Complex Long Double Type is passed in Memory when Regcall
3896       // calling convention is used.
3897       FI.getReturnInfo() = getIndirectReturnResult(FI.getReturnType());
3898     else
3899       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
3900   }
3901 
3902   // If the return value is indirect, then the hidden argument is consuming one
3903   // integer register.
3904   if (FI.getReturnInfo().isIndirect())
3905     --FreeIntRegs;
3906 
3907   // The chain argument effectively gives us another free register.
3908   if (FI.isChainCall())
3909     ++FreeIntRegs;
3910 
3911   unsigned NumRequiredArgs = FI.getNumRequiredArgs();
3912   // AMD64-ABI 3.2.3p3: Once arguments are classified, the registers
3913   // get assigned (in left-to-right order) for passing as follows...
3914   unsigned ArgNo = 0;
3915   for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
3916        it != ie; ++it, ++ArgNo) {
3917     bool IsNamedArg = ArgNo < NumRequiredArgs;
3918 
3919     if (IsRegCall && it->type->isStructureOrClassType())
3920       it->info = classifyRegCallStructType(it->type, NeededInt, NeededSSE);
3921     else
3922       it->info = classifyArgumentType(it->type, FreeIntRegs, NeededInt,
3923                                       NeededSSE, IsNamedArg);
3924 
3925     // AMD64-ABI 3.2.3p3: If there are no registers available for any
3926     // eightbyte of an argument, the whole argument is passed on the
3927     // stack. If registers have already been assigned for some
3928     // eightbytes of such an argument, the assignments get reverted.
3929     if (FreeIntRegs >= NeededInt && FreeSSERegs >= NeededSSE) {
3930       FreeIntRegs -= NeededInt;
3931       FreeSSERegs -= NeededSSE;
3932     } else {
3933       it->info = getIndirectResult(it->type, FreeIntRegs);
3934     }
3935   }
3936 }
3937 
EmitX86_64VAArgFromMemory(CodeGenFunction & CGF,Address VAListAddr,QualType Ty)3938 static Address EmitX86_64VAArgFromMemory(CodeGenFunction &CGF,
3939                                          Address VAListAddr, QualType Ty) {
3940   Address overflow_arg_area_p =
3941       CGF.Builder.CreateStructGEP(VAListAddr, 2, "overflow_arg_area_p");
3942   llvm::Value *overflow_arg_area =
3943     CGF.Builder.CreateLoad(overflow_arg_area_p, "overflow_arg_area");
3944 
3945   // AMD64-ABI 3.5.7p5: Step 7. Align l->overflow_arg_area upwards to a 16
3946   // byte boundary if alignment needed by type exceeds 8 byte boundary.
3947   // It isn't stated explicitly in the standard, but in practice we use
3948   // alignment greater than 16 where necessary.
3949   CharUnits Align = CGF.getContext().getTypeAlignInChars(Ty);
3950   if (Align > CharUnits::fromQuantity(8)) {
3951     overflow_arg_area = emitRoundPointerUpToAlignment(CGF, overflow_arg_area,
3952                                                       Align);
3953   }
3954 
3955   // AMD64-ABI 3.5.7p5: Step 8. Fetch type from l->overflow_arg_area.
3956   llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
3957   llvm::Value *Res =
3958     CGF.Builder.CreateBitCast(overflow_arg_area,
3959                               llvm::PointerType::getUnqual(LTy));
3960 
3961   // AMD64-ABI 3.5.7p5: Step 9. Set l->overflow_arg_area to:
3962   // l->overflow_arg_area + sizeof(type).
3963   // AMD64-ABI 3.5.7p5: Step 10. Align l->overflow_arg_area upwards to
3964   // an 8 byte boundary.
3965 
3966   uint64_t SizeInBytes = (CGF.getContext().getTypeSize(Ty) + 7) / 8;
3967   llvm::Value *Offset =
3968       llvm::ConstantInt::get(CGF.Int32Ty, (SizeInBytes + 7)  & ~7);
3969   overflow_arg_area = CGF.Builder.CreateGEP(CGF.Int8Ty, overflow_arg_area,
3970                                             Offset, "overflow_arg_area.next");
3971   CGF.Builder.CreateStore(overflow_arg_area, overflow_arg_area_p);
3972 
3973   // AMD64-ABI 3.5.7p5: Step 11. Return the fetched type.
3974   return Address(Res, Align);
3975 }
3976 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const3977 Address X86_64ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
3978                                  QualType Ty) const {
3979   // Assume that va_list type is correct; should be pointer to LLVM type:
3980   // struct {
3981   //   i32 gp_offset;
3982   //   i32 fp_offset;
3983   //   i8* overflow_arg_area;
3984   //   i8* reg_save_area;
3985   // };
3986   unsigned neededInt, neededSSE;
3987 
3988   Ty = getContext().getCanonicalType(Ty);
3989   ABIArgInfo AI = classifyArgumentType(Ty, 0, neededInt, neededSSE,
3990                                        /*isNamedArg*/false);
3991 
3992   // AMD64-ABI 3.5.7p5: Step 1. Determine whether type may be passed
3993   // in the registers. If not go to step 7.
3994   if (!neededInt && !neededSSE)
3995     return EmitX86_64VAArgFromMemory(CGF, VAListAddr, Ty);
3996 
3997   // AMD64-ABI 3.5.7p5: Step 2. Compute num_gp to hold the number of
3998   // general purpose registers needed to pass type and num_fp to hold
3999   // the number of floating point registers needed.
4000 
4001   // AMD64-ABI 3.5.7p5: Step 3. Verify whether arguments fit into
4002   // registers. In the case: l->gp_offset > 48 - num_gp * 8 or
4003   // l->fp_offset > 304 - num_fp * 16 go to step 7.
4004   //
4005   // NOTE: 304 is a typo, there are (6 * 8 + 8 * 16) = 176 bytes of
4006   // register save space).
4007 
4008   llvm::Value *InRegs = nullptr;
4009   Address gp_offset_p = Address::invalid(), fp_offset_p = Address::invalid();
4010   llvm::Value *gp_offset = nullptr, *fp_offset = nullptr;
4011   if (neededInt) {
4012     gp_offset_p = CGF.Builder.CreateStructGEP(VAListAddr, 0, "gp_offset_p");
4013     gp_offset = CGF.Builder.CreateLoad(gp_offset_p, "gp_offset");
4014     InRegs = llvm::ConstantInt::get(CGF.Int32Ty, 48 - neededInt * 8);
4015     InRegs = CGF.Builder.CreateICmpULE(gp_offset, InRegs, "fits_in_gp");
4016   }
4017 
4018   if (neededSSE) {
4019     fp_offset_p = CGF.Builder.CreateStructGEP(VAListAddr, 1, "fp_offset_p");
4020     fp_offset = CGF.Builder.CreateLoad(fp_offset_p, "fp_offset");
4021     llvm::Value *FitsInFP =
4022       llvm::ConstantInt::get(CGF.Int32Ty, 176 - neededSSE * 16);
4023     FitsInFP = CGF.Builder.CreateICmpULE(fp_offset, FitsInFP, "fits_in_fp");
4024     InRegs = InRegs ? CGF.Builder.CreateAnd(InRegs, FitsInFP) : FitsInFP;
4025   }
4026 
4027   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
4028   llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
4029   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
4030   CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
4031 
4032   // Emit code to load the value if it was passed in registers.
4033 
4034   CGF.EmitBlock(InRegBlock);
4035 
4036   // AMD64-ABI 3.5.7p5: Step 4. Fetch type from l->reg_save_area with
4037   // an offset of l->gp_offset and/or l->fp_offset. This may require
4038   // copying to a temporary location in case the parameter is passed
4039   // in different register classes or requires an alignment greater
4040   // than 8 for general purpose registers and 16 for XMM registers.
4041   //
4042   // FIXME: This really results in shameful code when we end up needing to
4043   // collect arguments from different places; often what should result in a
4044   // simple assembling of a structure from scattered addresses has many more
4045   // loads than necessary. Can we clean this up?
4046   llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
4047   llvm::Value *RegSaveArea = CGF.Builder.CreateLoad(
4048       CGF.Builder.CreateStructGEP(VAListAddr, 3), "reg_save_area");
4049 
4050   Address RegAddr = Address::invalid();
4051   if (neededInt && neededSSE) {
4052     // FIXME: Cleanup.
4053     assert(AI.isDirect() && "Unexpected ABI info for mixed regs");
4054     llvm::StructType *ST = cast<llvm::StructType>(AI.getCoerceToType());
4055     Address Tmp = CGF.CreateMemTemp(Ty);
4056     Tmp = CGF.Builder.CreateElementBitCast(Tmp, ST);
4057     assert(ST->getNumElements() == 2 && "Unexpected ABI info for mixed regs");
4058     llvm::Type *TyLo = ST->getElementType(0);
4059     llvm::Type *TyHi = ST->getElementType(1);
4060     assert((TyLo->isFPOrFPVectorTy() ^ TyHi->isFPOrFPVectorTy()) &&
4061            "Unexpected ABI info for mixed regs");
4062     llvm::Type *PTyLo = llvm::PointerType::getUnqual(TyLo);
4063     llvm::Type *PTyHi = llvm::PointerType::getUnqual(TyHi);
4064     llvm::Value *GPAddr =
4065         CGF.Builder.CreateGEP(CGF.Int8Ty, RegSaveArea, gp_offset);
4066     llvm::Value *FPAddr =
4067         CGF.Builder.CreateGEP(CGF.Int8Ty, RegSaveArea, fp_offset);
4068     llvm::Value *RegLoAddr = TyLo->isFPOrFPVectorTy() ? FPAddr : GPAddr;
4069     llvm::Value *RegHiAddr = TyLo->isFPOrFPVectorTy() ? GPAddr : FPAddr;
4070 
4071     // Copy the first element.
4072     // FIXME: Our choice of alignment here and below is probably pessimistic.
4073     llvm::Value *V = CGF.Builder.CreateAlignedLoad(
4074         TyLo, CGF.Builder.CreateBitCast(RegLoAddr, PTyLo),
4075         CharUnits::fromQuantity(getDataLayout().getABITypeAlignment(TyLo)));
4076     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 0));
4077 
4078     // Copy the second element.
4079     V = CGF.Builder.CreateAlignedLoad(
4080         TyHi, CGF.Builder.CreateBitCast(RegHiAddr, PTyHi),
4081         CharUnits::fromQuantity(getDataLayout().getABITypeAlignment(TyHi)));
4082     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1));
4083 
4084     RegAddr = CGF.Builder.CreateElementBitCast(Tmp, LTy);
4085   } else if (neededInt) {
4086     RegAddr = Address(CGF.Builder.CreateGEP(CGF.Int8Ty, RegSaveArea, gp_offset),
4087                       CharUnits::fromQuantity(8));
4088     RegAddr = CGF.Builder.CreateElementBitCast(RegAddr, LTy);
4089 
4090     // Copy to a temporary if necessary to ensure the appropriate alignment.
4091     auto TInfo = getContext().getTypeInfoInChars(Ty);
4092     uint64_t TySize = TInfo.Width.getQuantity();
4093     CharUnits TyAlign = TInfo.Align;
4094 
4095     // Copy into a temporary if the type is more aligned than the
4096     // register save area.
4097     if (TyAlign.getQuantity() > 8) {
4098       Address Tmp = CGF.CreateMemTemp(Ty);
4099       CGF.Builder.CreateMemCpy(Tmp, RegAddr, TySize, false);
4100       RegAddr = Tmp;
4101     }
4102 
4103   } else if (neededSSE == 1) {
4104     RegAddr = Address(CGF.Builder.CreateGEP(CGF.Int8Ty, RegSaveArea, fp_offset),
4105                       CharUnits::fromQuantity(16));
4106     RegAddr = CGF.Builder.CreateElementBitCast(RegAddr, LTy);
4107   } else {
4108     assert(neededSSE == 2 && "Invalid number of needed registers!");
4109     // SSE registers are spaced 16 bytes apart in the register save
4110     // area, we need to collect the two eightbytes together.
4111     // The ABI isn't explicit about this, but it seems reasonable
4112     // to assume that the slots are 16-byte aligned, since the stack is
4113     // naturally 16-byte aligned and the prologue is expected to store
4114     // all the SSE registers to the RSA.
4115     Address RegAddrLo = Address(CGF.Builder.CreateGEP(CGF.Int8Ty, RegSaveArea,
4116                                                       fp_offset),
4117                                 CharUnits::fromQuantity(16));
4118     Address RegAddrHi =
4119       CGF.Builder.CreateConstInBoundsByteGEP(RegAddrLo,
4120                                              CharUnits::fromQuantity(16));
4121     llvm::Type *ST = AI.canHaveCoerceToType()
4122                          ? AI.getCoerceToType()
4123                          : llvm::StructType::get(CGF.DoubleTy, CGF.DoubleTy);
4124     llvm::Value *V;
4125     Address Tmp = CGF.CreateMemTemp(Ty);
4126     Tmp = CGF.Builder.CreateElementBitCast(Tmp, ST);
4127     V = CGF.Builder.CreateLoad(CGF.Builder.CreateElementBitCast(
4128         RegAddrLo, ST->getStructElementType(0)));
4129     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 0));
4130     V = CGF.Builder.CreateLoad(CGF.Builder.CreateElementBitCast(
4131         RegAddrHi, ST->getStructElementType(1)));
4132     CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1));
4133 
4134     RegAddr = CGF.Builder.CreateElementBitCast(Tmp, LTy);
4135   }
4136 
4137   // AMD64-ABI 3.5.7p5: Step 5. Set:
4138   // l->gp_offset = l->gp_offset + num_gp * 8
4139   // l->fp_offset = l->fp_offset + num_fp * 16.
4140   if (neededInt) {
4141     llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededInt * 8);
4142     CGF.Builder.CreateStore(CGF.Builder.CreateAdd(gp_offset, Offset),
4143                             gp_offset_p);
4144   }
4145   if (neededSSE) {
4146     llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededSSE * 16);
4147     CGF.Builder.CreateStore(CGF.Builder.CreateAdd(fp_offset, Offset),
4148                             fp_offset_p);
4149   }
4150   CGF.EmitBranch(ContBlock);
4151 
4152   // Emit code to load the value if it was passed in memory.
4153 
4154   CGF.EmitBlock(InMemBlock);
4155   Address MemAddr = EmitX86_64VAArgFromMemory(CGF, VAListAddr, Ty);
4156 
4157   // Return the appropriate result.
4158 
4159   CGF.EmitBlock(ContBlock);
4160   Address ResAddr = emitMergePHI(CGF, RegAddr, InRegBlock, MemAddr, InMemBlock,
4161                                  "vaarg.addr");
4162   return ResAddr;
4163 }
4164 
EmitMSVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const4165 Address X86_64ABIInfo::EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
4166                                    QualType Ty) const {
4167   // MS x64 ABI requirement: "Any argument that doesn't fit in 8 bytes, or is
4168   // not 1, 2, 4, or 8 bytes, must be passed by reference."
4169   uint64_t Width = getContext().getTypeSize(Ty);
4170   bool IsIndirect = Width > 64 || !llvm::isPowerOf2_64(Width);
4171 
4172   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, IsIndirect,
4173                           CGF.getContext().getTypeInfoInChars(Ty),
4174                           CharUnits::fromQuantity(8),
4175                           /*allowHigherAlign*/ false);
4176 }
4177 
reclassifyHvaArgForVectorCall(QualType Ty,unsigned & FreeSSERegs,const ABIArgInfo & current) const4178 ABIArgInfo WinX86_64ABIInfo::reclassifyHvaArgForVectorCall(
4179     QualType Ty, unsigned &FreeSSERegs, const ABIArgInfo &current) const {
4180   const Type *Base = nullptr;
4181   uint64_t NumElts = 0;
4182 
4183   if (!Ty->isBuiltinType() && !Ty->isVectorType() &&
4184       isHomogeneousAggregate(Ty, Base, NumElts) && FreeSSERegs >= NumElts) {
4185     FreeSSERegs -= NumElts;
4186     return getDirectX86Hva();
4187   }
4188   return current;
4189 }
4190 
classify(QualType Ty,unsigned & FreeSSERegs,bool IsReturnType,bool IsVectorCall,bool IsRegCall) const4191 ABIArgInfo WinX86_64ABIInfo::classify(QualType Ty, unsigned &FreeSSERegs,
4192                                       bool IsReturnType, bool IsVectorCall,
4193                                       bool IsRegCall) const {
4194 
4195   if (Ty->isVoidType())
4196     return ABIArgInfo::getIgnore();
4197 
4198   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
4199     Ty = EnumTy->getDecl()->getIntegerType();
4200 
4201   TypeInfo Info = getContext().getTypeInfo(Ty);
4202   uint64_t Width = Info.Width;
4203   CharUnits Align = getContext().toCharUnitsFromBits(Info.Align);
4204 
4205   const RecordType *RT = Ty->getAs<RecordType>();
4206   if (RT) {
4207     if (!IsReturnType) {
4208       if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, getCXXABI()))
4209         return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
4210     }
4211 
4212     if (RT->getDecl()->hasFlexibleArrayMember())
4213       return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
4214 
4215   }
4216 
4217   const Type *Base = nullptr;
4218   uint64_t NumElts = 0;
4219   // vectorcall adds the concept of a homogenous vector aggregate, similar to
4220   // other targets.
4221   if ((IsVectorCall || IsRegCall) &&
4222       isHomogeneousAggregate(Ty, Base, NumElts)) {
4223     if (IsRegCall) {
4224       if (FreeSSERegs >= NumElts) {
4225         FreeSSERegs -= NumElts;
4226         if (IsReturnType || Ty->isBuiltinType() || Ty->isVectorType())
4227           return ABIArgInfo::getDirect();
4228         return ABIArgInfo::getExpand();
4229       }
4230       return ABIArgInfo::getIndirect(Align, /*ByVal=*/false);
4231     } else if (IsVectorCall) {
4232       if (FreeSSERegs >= NumElts &&
4233           (IsReturnType || Ty->isBuiltinType() || Ty->isVectorType())) {
4234         FreeSSERegs -= NumElts;
4235         return ABIArgInfo::getDirect();
4236       } else if (IsReturnType) {
4237         return ABIArgInfo::getExpand();
4238       } else if (!Ty->isBuiltinType() && !Ty->isVectorType()) {
4239         // HVAs are delayed and reclassified in the 2nd step.
4240         return ABIArgInfo::getIndirect(Align, /*ByVal=*/false);
4241       }
4242     }
4243   }
4244 
4245   if (Ty->isMemberPointerType()) {
4246     // If the member pointer is represented by an LLVM int or ptr, pass it
4247     // directly.
4248     llvm::Type *LLTy = CGT.ConvertType(Ty);
4249     if (LLTy->isPointerTy() || LLTy->isIntegerTy())
4250       return ABIArgInfo::getDirect();
4251   }
4252 
4253   if (RT || Ty->isAnyComplexType() || Ty->isMemberPointerType()) {
4254     // MS x64 ABI requirement: "Any argument that doesn't fit in 8 bytes, or is
4255     // not 1, 2, 4, or 8 bytes, must be passed by reference."
4256     if (Width > 64 || !llvm::isPowerOf2_64(Width))
4257       return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
4258 
4259     // Otherwise, coerce it to a small integer.
4260     return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), Width));
4261   }
4262 
4263   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
4264     switch (BT->getKind()) {
4265     case BuiltinType::Bool:
4266       // Bool type is always extended to the ABI, other builtin types are not
4267       // extended.
4268       return ABIArgInfo::getExtend(Ty);
4269 
4270     case BuiltinType::LongDouble:
4271       // Mingw64 GCC uses the old 80 bit extended precision floating point
4272       // unit. It passes them indirectly through memory.
4273       if (IsMingw64) {
4274         const llvm::fltSemantics *LDF = &getTarget().getLongDoubleFormat();
4275         if (LDF == &llvm::APFloat::x87DoubleExtended())
4276           return ABIArgInfo::getIndirect(Align, /*ByVal=*/false);
4277       }
4278       break;
4279 
4280     case BuiltinType::Int128:
4281     case BuiltinType::UInt128:
4282       // If it's a parameter type, the normal ABI rule is that arguments larger
4283       // than 8 bytes are passed indirectly. GCC follows it. We follow it too,
4284       // even though it isn't particularly efficient.
4285       if (!IsReturnType)
4286         return ABIArgInfo::getIndirect(Align, /*ByVal=*/false);
4287 
4288       // Mingw64 GCC returns i128 in XMM0. Coerce to v2i64 to handle that.
4289       // Clang matches them for compatibility.
4290       return ABIArgInfo::getDirect(llvm::FixedVectorType::get(
4291           llvm::Type::getInt64Ty(getVMContext()), 2));
4292 
4293     default:
4294       break;
4295     }
4296   }
4297 
4298   if (Ty->isExtIntType()) {
4299     // MS x64 ABI requirement: "Any argument that doesn't fit in 8 bytes, or is
4300     // not 1, 2, 4, or 8 bytes, must be passed by reference."
4301     // However, non-power-of-two _ExtInts will be passed as 1,2,4 or 8 bytes
4302     // anyway as long is it fits in them, so we don't have to check the power of
4303     // 2.
4304     if (Width <= 64)
4305       return ABIArgInfo::getDirect();
4306     return ABIArgInfo::getIndirect(Align, /*ByVal=*/false);
4307   }
4308 
4309   return ABIArgInfo::getDirect();
4310 }
4311 
computeInfo(CGFunctionInfo & FI) const4312 void WinX86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
4313   const unsigned CC = FI.getCallingConvention();
4314   bool IsVectorCall = CC == llvm::CallingConv::X86_VectorCall;
4315   bool IsRegCall = CC == llvm::CallingConv::X86_RegCall;
4316 
4317   // If __attribute__((sysv_abi)) is in use, use the SysV argument
4318   // classification rules.
4319   if (CC == llvm::CallingConv::X86_64_SysV) {
4320     X86_64ABIInfo SysVABIInfo(CGT, AVXLevel);
4321     SysVABIInfo.computeInfo(FI);
4322     return;
4323   }
4324 
4325   unsigned FreeSSERegs = 0;
4326   if (IsVectorCall) {
4327     // We can use up to 4 SSE return registers with vectorcall.
4328     FreeSSERegs = 4;
4329   } else if (IsRegCall) {
4330     // RegCall gives us 16 SSE registers.
4331     FreeSSERegs = 16;
4332   }
4333 
4334   if (!getCXXABI().classifyReturnType(FI))
4335     FI.getReturnInfo() = classify(FI.getReturnType(), FreeSSERegs, true,
4336                                   IsVectorCall, IsRegCall);
4337 
4338   if (IsVectorCall) {
4339     // We can use up to 6 SSE register parameters with vectorcall.
4340     FreeSSERegs = 6;
4341   } else if (IsRegCall) {
4342     // RegCall gives us 16 SSE registers, we can reuse the return registers.
4343     FreeSSERegs = 16;
4344   }
4345 
4346   unsigned ArgNum = 0;
4347   unsigned ZeroSSERegs = 0;
4348   for (auto &I : FI.arguments()) {
4349     // Vectorcall in x64 only permits the first 6 arguments to be passed as
4350     // XMM/YMM registers. After the sixth argument, pretend no vector
4351     // registers are left.
4352     unsigned *MaybeFreeSSERegs =
4353         (IsVectorCall && ArgNum >= 6) ? &ZeroSSERegs : &FreeSSERegs;
4354     I.info =
4355         classify(I.type, *MaybeFreeSSERegs, false, IsVectorCall, IsRegCall);
4356     ++ArgNum;
4357   }
4358 
4359   if (IsVectorCall) {
4360     // For vectorcall, assign aggregate HVAs to any free vector registers in a
4361     // second pass.
4362     for (auto &I : FI.arguments())
4363       I.info = reclassifyHvaArgForVectorCall(I.type, FreeSSERegs, I.info);
4364   }
4365 }
4366 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const4367 Address WinX86_64ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
4368                                     QualType Ty) const {
4369   // MS x64 ABI requirement: "Any argument that doesn't fit in 8 bytes, or is
4370   // not 1, 2, 4, or 8 bytes, must be passed by reference."
4371   uint64_t Width = getContext().getTypeSize(Ty);
4372   bool IsIndirect = Width > 64 || !llvm::isPowerOf2_64(Width);
4373 
4374   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, IsIndirect,
4375                           CGF.getContext().getTypeInfoInChars(Ty),
4376                           CharUnits::fromQuantity(8),
4377                           /*allowHigherAlign*/ false);
4378 }
4379 
PPC_initDwarfEHRegSizeTable(CodeGen::CodeGenFunction & CGF,llvm::Value * Address,bool Is64Bit,bool IsAIX)4380 static bool PPC_initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
4381                                         llvm::Value *Address, bool Is64Bit,
4382                                         bool IsAIX) {
4383   // This is calculated from the LLVM and GCC tables and verified
4384   // against gcc output.  AFAIK all PPC ABIs use the same encoding.
4385 
4386   CodeGen::CGBuilderTy &Builder = CGF.Builder;
4387 
4388   llvm::IntegerType *i8 = CGF.Int8Ty;
4389   llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
4390   llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
4391   llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
4392 
4393   // 0-31: r0-31, the 4-byte or 8-byte general-purpose registers
4394   AssignToArrayRange(Builder, Address, Is64Bit ? Eight8 : Four8, 0, 31);
4395 
4396   // 32-63: fp0-31, the 8-byte floating-point registers
4397   AssignToArrayRange(Builder, Address, Eight8, 32, 63);
4398 
4399   // 64-67 are various 4-byte or 8-byte special-purpose registers:
4400   // 64: mq
4401   // 65: lr
4402   // 66: ctr
4403   // 67: ap
4404   AssignToArrayRange(Builder, Address, Is64Bit ? Eight8 : Four8, 64, 67);
4405 
4406   // 68-76 are various 4-byte special-purpose registers:
4407   // 68-75 cr0-7
4408   // 76: xer
4409   AssignToArrayRange(Builder, Address, Four8, 68, 76);
4410 
4411   // 77-108: v0-31, the 16-byte vector registers
4412   AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
4413 
4414   // 109: vrsave
4415   // 110: vscr
4416   AssignToArrayRange(Builder, Address, Is64Bit ? Eight8 : Four8, 109, 110);
4417 
4418   // AIX does not utilize the rest of the registers.
4419   if (IsAIX)
4420     return false;
4421 
4422   // 111: spe_acc
4423   // 112: spefscr
4424   // 113: sfp
4425   AssignToArrayRange(Builder, Address, Is64Bit ? Eight8 : Four8, 111, 113);
4426 
4427   if (!Is64Bit)
4428     return false;
4429 
4430   // TODO: Need to verify if these registers are used on 64 bit AIX with Power8
4431   // or above CPU.
4432   // 64-bit only registers:
4433   // 114: tfhar
4434   // 115: tfiar
4435   // 116: texasr
4436   AssignToArrayRange(Builder, Address, Eight8, 114, 116);
4437 
4438   return false;
4439 }
4440 
4441 // AIX
4442 namespace {
4443 /// AIXABIInfo - The AIX XCOFF ABI information.
4444 class AIXABIInfo : public ABIInfo {
4445   const bool Is64Bit;
4446   const unsigned PtrByteSize;
4447   CharUnits getParamTypeAlignment(QualType Ty) const;
4448 
4449 public:
AIXABIInfo(CodeGen::CodeGenTypes & CGT,bool Is64Bit)4450   AIXABIInfo(CodeGen::CodeGenTypes &CGT, bool Is64Bit)
4451       : ABIInfo(CGT), Is64Bit(Is64Bit), PtrByteSize(Is64Bit ? 8 : 4) {}
4452 
4453   bool isPromotableTypeForABI(QualType Ty) const;
4454 
4455   ABIArgInfo classifyReturnType(QualType RetTy) const;
4456   ABIArgInfo classifyArgumentType(QualType Ty) const;
4457 
computeInfo(CGFunctionInfo & FI) const4458   void computeInfo(CGFunctionInfo &FI) const override {
4459     if (!getCXXABI().classifyReturnType(FI))
4460       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
4461 
4462     for (auto &I : FI.arguments())
4463       I.info = classifyArgumentType(I.type);
4464   }
4465 
4466   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
4467                     QualType Ty) const override;
4468 };
4469 
4470 class AIXTargetCodeGenInfo : public TargetCodeGenInfo {
4471   const bool Is64Bit;
4472 
4473 public:
AIXTargetCodeGenInfo(CodeGen::CodeGenTypes & CGT,bool Is64Bit)4474   AIXTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool Is64Bit)
4475       : TargetCodeGenInfo(std::make_unique<AIXABIInfo>(CGT, Is64Bit)),
4476         Is64Bit(Is64Bit) {}
getDwarfEHStackPointer(CodeGen::CodeGenModule & M) const4477   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
4478     return 1; // r1 is the dedicated stack pointer
4479   }
4480 
4481   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
4482                                llvm::Value *Address) const override;
4483 };
4484 } // namespace
4485 
4486 // Return true if the ABI requires Ty to be passed sign- or zero-
4487 // extended to 32/64 bits.
isPromotableTypeForABI(QualType Ty) const4488 bool AIXABIInfo::isPromotableTypeForABI(QualType Ty) const {
4489   // Treat an enum type as its underlying type.
4490   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
4491     Ty = EnumTy->getDecl()->getIntegerType();
4492 
4493   // Promotable integer types are required to be promoted by the ABI.
4494   if (Ty->isPromotableIntegerType())
4495     return true;
4496 
4497   if (!Is64Bit)
4498     return false;
4499 
4500   // For 64 bit mode, in addition to the usual promotable integer types, we also
4501   // need to extend all 32-bit types, since the ABI requires promotion to 64
4502   // bits.
4503   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
4504     switch (BT->getKind()) {
4505     case BuiltinType::Int:
4506     case BuiltinType::UInt:
4507       return true;
4508     default:
4509       break;
4510     }
4511 
4512   return false;
4513 }
4514 
classifyReturnType(QualType RetTy) const4515 ABIArgInfo AIXABIInfo::classifyReturnType(QualType RetTy) const {
4516   if (RetTy->isAnyComplexType())
4517     return ABIArgInfo::getDirect();
4518 
4519   if (RetTy->isVectorType())
4520     return ABIArgInfo::getDirect();
4521 
4522   if (RetTy->isVoidType())
4523     return ABIArgInfo::getIgnore();
4524 
4525   if (isAggregateTypeForABI(RetTy))
4526     return getNaturalAlignIndirect(RetTy);
4527 
4528   return (isPromotableTypeForABI(RetTy) ? ABIArgInfo::getExtend(RetTy)
4529                                         : ABIArgInfo::getDirect());
4530 }
4531 
classifyArgumentType(QualType Ty) const4532 ABIArgInfo AIXABIInfo::classifyArgumentType(QualType Ty) const {
4533   Ty = useFirstFieldIfTransparentUnion(Ty);
4534 
4535   if (Ty->isAnyComplexType())
4536     return ABIArgInfo::getDirect();
4537 
4538   if (Ty->isVectorType())
4539     return ABIArgInfo::getDirect();
4540 
4541   if (isAggregateTypeForABI(Ty)) {
4542     // Records with non-trivial destructors/copy-constructors should not be
4543     // passed by value.
4544     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
4545       return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
4546 
4547     CharUnits CCAlign = getParamTypeAlignment(Ty);
4548     CharUnits TyAlign = getContext().getTypeAlignInChars(Ty);
4549 
4550     return ABIArgInfo::getIndirect(CCAlign, /*ByVal*/ true,
4551                                    /*Realign*/ TyAlign > CCAlign);
4552   }
4553 
4554   return (isPromotableTypeForABI(Ty) ? ABIArgInfo::getExtend(Ty)
4555                                      : ABIArgInfo::getDirect());
4556 }
4557 
getParamTypeAlignment(QualType Ty) const4558 CharUnits AIXABIInfo::getParamTypeAlignment(QualType Ty) const {
4559   // Complex types are passed just like their elements.
4560   if (const ComplexType *CTy = Ty->getAs<ComplexType>())
4561     Ty = CTy->getElementType();
4562 
4563   if (Ty->isVectorType())
4564     return CharUnits::fromQuantity(16);
4565 
4566   // If the structure contains a vector type, the alignment is 16.
4567   if (isRecordWithSIMDVectorType(getContext(), Ty))
4568     return CharUnits::fromQuantity(16);
4569 
4570   return CharUnits::fromQuantity(PtrByteSize);
4571 }
4572 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const4573 Address AIXABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
4574                               QualType Ty) const {
4575   if (Ty->isAnyComplexType())
4576     llvm::report_fatal_error("complex type is not supported on AIX yet");
4577 
4578   auto TypeInfo = getContext().getTypeInfoInChars(Ty);
4579   TypeInfo.Align = getParamTypeAlignment(Ty);
4580 
4581   CharUnits SlotSize = CharUnits::fromQuantity(PtrByteSize);
4582 
4583   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*Indirect*/ false, TypeInfo,
4584                           SlotSize, /*AllowHigher*/ true);
4585 }
4586 
initDwarfEHRegSizeTable(CodeGen::CodeGenFunction & CGF,llvm::Value * Address) const4587 bool AIXTargetCodeGenInfo::initDwarfEHRegSizeTable(
4588     CodeGen::CodeGenFunction &CGF, llvm::Value *Address) const {
4589   return PPC_initDwarfEHRegSizeTable(CGF, Address, Is64Bit, /*IsAIX*/ true);
4590 }
4591 
4592 // PowerPC-32
4593 namespace {
4594 /// PPC32_SVR4_ABIInfo - The 32-bit PowerPC ELF (SVR4) ABI information.
4595 class PPC32_SVR4_ABIInfo : public DefaultABIInfo {
4596   bool IsSoftFloatABI;
4597   bool IsRetSmallStructInRegABI;
4598 
4599   CharUnits getParamTypeAlignment(QualType Ty) const;
4600 
4601 public:
PPC32_SVR4_ABIInfo(CodeGen::CodeGenTypes & CGT,bool SoftFloatABI,bool RetSmallStructInRegABI)4602   PPC32_SVR4_ABIInfo(CodeGen::CodeGenTypes &CGT, bool SoftFloatABI,
4603                      bool RetSmallStructInRegABI)
4604       : DefaultABIInfo(CGT), IsSoftFloatABI(SoftFloatABI),
4605         IsRetSmallStructInRegABI(RetSmallStructInRegABI) {}
4606 
4607   ABIArgInfo classifyReturnType(QualType RetTy) const;
4608 
computeInfo(CGFunctionInfo & FI) const4609   void computeInfo(CGFunctionInfo &FI) const override {
4610     if (!getCXXABI().classifyReturnType(FI))
4611       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
4612     for (auto &I : FI.arguments())
4613       I.info = classifyArgumentType(I.type);
4614   }
4615 
4616   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
4617                     QualType Ty) const override;
4618 };
4619 
4620 class PPC32TargetCodeGenInfo : public TargetCodeGenInfo {
4621 public:
PPC32TargetCodeGenInfo(CodeGenTypes & CGT,bool SoftFloatABI,bool RetSmallStructInRegABI)4622   PPC32TargetCodeGenInfo(CodeGenTypes &CGT, bool SoftFloatABI,
4623                          bool RetSmallStructInRegABI)
4624       : TargetCodeGenInfo(std::make_unique<PPC32_SVR4_ABIInfo>(
4625             CGT, SoftFloatABI, RetSmallStructInRegABI)) {}
4626 
4627   static bool isStructReturnInRegABI(const llvm::Triple &Triple,
4628                                      const CodeGenOptions &Opts);
4629 
getDwarfEHStackPointer(CodeGen::CodeGenModule & M) const4630   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
4631     // This is recovered from gcc output.
4632     return 1; // r1 is the dedicated stack pointer
4633   }
4634 
4635   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
4636                                llvm::Value *Address) const override;
4637 };
4638 }
4639 
getParamTypeAlignment(QualType Ty) const4640 CharUnits PPC32_SVR4_ABIInfo::getParamTypeAlignment(QualType Ty) const {
4641   // Complex types are passed just like their elements.
4642   if (const ComplexType *CTy = Ty->getAs<ComplexType>())
4643     Ty = CTy->getElementType();
4644 
4645   if (Ty->isVectorType())
4646     return CharUnits::fromQuantity(getContext().getTypeSize(Ty) == 128 ? 16
4647                                                                        : 4);
4648 
4649   // For single-element float/vector structs, we consider the whole type
4650   // to have the same alignment requirements as its single element.
4651   const Type *AlignTy = nullptr;
4652   if (const Type *EltType = isSingleElementStruct(Ty, getContext())) {
4653     const BuiltinType *BT = EltType->getAs<BuiltinType>();
4654     if ((EltType->isVectorType() && getContext().getTypeSize(EltType) == 128) ||
4655         (BT && BT->isFloatingPoint()))
4656       AlignTy = EltType;
4657   }
4658 
4659   if (AlignTy)
4660     return CharUnits::fromQuantity(AlignTy->isVectorType() ? 16 : 4);
4661   return CharUnits::fromQuantity(4);
4662 }
4663 
classifyReturnType(QualType RetTy) const4664 ABIArgInfo PPC32_SVR4_ABIInfo::classifyReturnType(QualType RetTy) const {
4665   uint64_t Size;
4666 
4667   // -msvr4-struct-return puts small aggregates in GPR3 and GPR4.
4668   if (isAggregateTypeForABI(RetTy) && IsRetSmallStructInRegABI &&
4669       (Size = getContext().getTypeSize(RetTy)) <= 64) {
4670     // System V ABI (1995), page 3-22, specified:
4671     // > A structure or union whose size is less than or equal to 8 bytes
4672     // > shall be returned in r3 and r4, as if it were first stored in the
4673     // > 8-byte aligned memory area and then the low addressed word were
4674     // > loaded into r3 and the high-addressed word into r4.  Bits beyond
4675     // > the last member of the structure or union are not defined.
4676     //
4677     // GCC for big-endian PPC32 inserts the pad before the first member,
4678     // not "beyond the last member" of the struct.  To stay compatible
4679     // with GCC, we coerce the struct to an integer of the same size.
4680     // LLVM will extend it and return i32 in r3, or i64 in r3:r4.
4681     if (Size == 0)
4682       return ABIArgInfo::getIgnore();
4683     else {
4684       llvm::Type *CoerceTy = llvm::Type::getIntNTy(getVMContext(), Size);
4685       return ABIArgInfo::getDirect(CoerceTy);
4686     }
4687   }
4688 
4689   return DefaultABIInfo::classifyReturnType(RetTy);
4690 }
4691 
4692 // TODO: this implementation is now likely redundant with
4693 // DefaultABIInfo::EmitVAArg.
EmitVAArg(CodeGenFunction & CGF,Address VAList,QualType Ty) const4694 Address PPC32_SVR4_ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAList,
4695                                       QualType Ty) const {
4696   if (getTarget().getTriple().isOSDarwin()) {
4697     auto TI = getContext().getTypeInfoInChars(Ty);
4698     TI.Align = getParamTypeAlignment(Ty);
4699 
4700     CharUnits SlotSize = CharUnits::fromQuantity(4);
4701     return emitVoidPtrVAArg(CGF, VAList, Ty,
4702                             classifyArgumentType(Ty).isIndirect(), TI, SlotSize,
4703                             /*AllowHigherAlign=*/true);
4704   }
4705 
4706   const unsigned OverflowLimit = 8;
4707   if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
4708     // TODO: Implement this. For now ignore.
4709     (void)CTy;
4710     return Address::invalid(); // FIXME?
4711   }
4712 
4713   // struct __va_list_tag {
4714   //   unsigned char gpr;
4715   //   unsigned char fpr;
4716   //   unsigned short reserved;
4717   //   void *overflow_arg_area;
4718   //   void *reg_save_area;
4719   // };
4720 
4721   bool isI64 = Ty->isIntegerType() && getContext().getTypeSize(Ty) == 64;
4722   bool isInt = !Ty->isFloatingType();
4723   bool isF64 = Ty->isFloatingType() && getContext().getTypeSize(Ty) == 64;
4724 
4725   // All aggregates are passed indirectly?  That doesn't seem consistent
4726   // with the argument-lowering code.
4727   bool isIndirect = isAggregateTypeForABI(Ty);
4728 
4729   CGBuilderTy &Builder = CGF.Builder;
4730 
4731   // The calling convention either uses 1-2 GPRs or 1 FPR.
4732   Address NumRegsAddr = Address::invalid();
4733   if (isInt || IsSoftFloatABI) {
4734     NumRegsAddr = Builder.CreateStructGEP(VAList, 0, "gpr");
4735   } else {
4736     NumRegsAddr = Builder.CreateStructGEP(VAList, 1, "fpr");
4737   }
4738 
4739   llvm::Value *NumRegs = Builder.CreateLoad(NumRegsAddr, "numUsedRegs");
4740 
4741   // "Align" the register count when TY is i64.
4742   if (isI64 || (isF64 && IsSoftFloatABI)) {
4743     NumRegs = Builder.CreateAdd(NumRegs, Builder.getInt8(1));
4744     NumRegs = Builder.CreateAnd(NumRegs, Builder.getInt8((uint8_t) ~1U));
4745   }
4746 
4747   llvm::Value *CC =
4748       Builder.CreateICmpULT(NumRegs, Builder.getInt8(OverflowLimit), "cond");
4749 
4750   llvm::BasicBlock *UsingRegs = CGF.createBasicBlock("using_regs");
4751   llvm::BasicBlock *UsingOverflow = CGF.createBasicBlock("using_overflow");
4752   llvm::BasicBlock *Cont = CGF.createBasicBlock("cont");
4753 
4754   Builder.CreateCondBr(CC, UsingRegs, UsingOverflow);
4755 
4756   llvm::Type *DirectTy = CGF.ConvertType(Ty);
4757   if (isIndirect) DirectTy = DirectTy->getPointerTo(0);
4758 
4759   // Case 1: consume registers.
4760   Address RegAddr = Address::invalid();
4761   {
4762     CGF.EmitBlock(UsingRegs);
4763 
4764     Address RegSaveAreaPtr = Builder.CreateStructGEP(VAList, 4);
4765     RegAddr = Address(Builder.CreateLoad(RegSaveAreaPtr),
4766                       CharUnits::fromQuantity(8));
4767     assert(RegAddr.getElementType() == CGF.Int8Ty);
4768 
4769     // Floating-point registers start after the general-purpose registers.
4770     if (!(isInt || IsSoftFloatABI)) {
4771       RegAddr = Builder.CreateConstInBoundsByteGEP(RegAddr,
4772                                                    CharUnits::fromQuantity(32));
4773     }
4774 
4775     // Get the address of the saved value by scaling the number of
4776     // registers we've used by the number of
4777     CharUnits RegSize = CharUnits::fromQuantity((isInt || IsSoftFloatABI) ? 4 : 8);
4778     llvm::Value *RegOffset =
4779       Builder.CreateMul(NumRegs, Builder.getInt8(RegSize.getQuantity()));
4780     RegAddr = Address(Builder.CreateInBoundsGEP(CGF.Int8Ty,
4781                                             RegAddr.getPointer(), RegOffset),
4782                       RegAddr.getAlignment().alignmentOfArrayElement(RegSize));
4783     RegAddr = Builder.CreateElementBitCast(RegAddr, DirectTy);
4784 
4785     // Increase the used-register count.
4786     NumRegs =
4787       Builder.CreateAdd(NumRegs,
4788                         Builder.getInt8((isI64 || (isF64 && IsSoftFloatABI)) ? 2 : 1));
4789     Builder.CreateStore(NumRegs, NumRegsAddr);
4790 
4791     CGF.EmitBranch(Cont);
4792   }
4793 
4794   // Case 2: consume space in the overflow area.
4795   Address MemAddr = Address::invalid();
4796   {
4797     CGF.EmitBlock(UsingOverflow);
4798 
4799     Builder.CreateStore(Builder.getInt8(OverflowLimit), NumRegsAddr);
4800 
4801     // Everything in the overflow area is rounded up to a size of at least 4.
4802     CharUnits OverflowAreaAlign = CharUnits::fromQuantity(4);
4803 
4804     CharUnits Size;
4805     if (!isIndirect) {
4806       auto TypeInfo = CGF.getContext().getTypeInfoInChars(Ty);
4807       Size = TypeInfo.Width.alignTo(OverflowAreaAlign);
4808     } else {
4809       Size = CGF.getPointerSize();
4810     }
4811 
4812     Address OverflowAreaAddr = Builder.CreateStructGEP(VAList, 3);
4813     Address OverflowArea(Builder.CreateLoad(OverflowAreaAddr, "argp.cur"),
4814                          OverflowAreaAlign);
4815     // Round up address of argument to alignment
4816     CharUnits Align = CGF.getContext().getTypeAlignInChars(Ty);
4817     if (Align > OverflowAreaAlign) {
4818       llvm::Value *Ptr = OverflowArea.getPointer();
4819       OverflowArea = Address(emitRoundPointerUpToAlignment(CGF, Ptr, Align),
4820                                                            Align);
4821     }
4822 
4823     MemAddr = Builder.CreateElementBitCast(OverflowArea, DirectTy);
4824 
4825     // Increase the overflow area.
4826     OverflowArea = Builder.CreateConstInBoundsByteGEP(OverflowArea, Size);
4827     Builder.CreateStore(OverflowArea.getPointer(), OverflowAreaAddr);
4828     CGF.EmitBranch(Cont);
4829   }
4830 
4831   CGF.EmitBlock(Cont);
4832 
4833   // Merge the cases with a phi.
4834   Address Result = emitMergePHI(CGF, RegAddr, UsingRegs, MemAddr, UsingOverflow,
4835                                 "vaarg.addr");
4836 
4837   // Load the pointer if the argument was passed indirectly.
4838   if (isIndirect) {
4839     Result = Address(Builder.CreateLoad(Result, "aggr"),
4840                      getContext().getTypeAlignInChars(Ty));
4841   }
4842 
4843   return Result;
4844 }
4845 
isStructReturnInRegABI(const llvm::Triple & Triple,const CodeGenOptions & Opts)4846 bool PPC32TargetCodeGenInfo::isStructReturnInRegABI(
4847     const llvm::Triple &Triple, const CodeGenOptions &Opts) {
4848   assert(Triple.isPPC32());
4849 
4850   switch (Opts.getStructReturnConvention()) {
4851   case CodeGenOptions::SRCK_Default:
4852     break;
4853   case CodeGenOptions::SRCK_OnStack: // -maix-struct-return
4854     return false;
4855   case CodeGenOptions::SRCK_InRegs: // -msvr4-struct-return
4856     return true;
4857   }
4858 
4859   if (Triple.isOSBinFormatELF() && !Triple.isOSLinux())
4860     return true;
4861 
4862   return false;
4863 }
4864 
4865 bool
initDwarfEHRegSizeTable(CodeGen::CodeGenFunction & CGF,llvm::Value * Address) const4866 PPC32TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
4867                                                 llvm::Value *Address) const {
4868   return PPC_initDwarfEHRegSizeTable(CGF, Address, /*Is64Bit*/ false,
4869                                      /*IsAIX*/ false);
4870 }
4871 
4872 // PowerPC-64
4873 
4874 namespace {
4875 /// PPC64_SVR4_ABIInfo - The 64-bit PowerPC ELF (SVR4) ABI information.
4876 class PPC64_SVR4_ABIInfo : public SwiftABIInfo {
4877 public:
4878   enum ABIKind {
4879     ELFv1 = 0,
4880     ELFv2
4881   };
4882 
4883 private:
4884   static const unsigned GPRBits = 64;
4885   ABIKind Kind;
4886   bool IsSoftFloatABI;
4887 
4888 public:
PPC64_SVR4_ABIInfo(CodeGen::CodeGenTypes & CGT,ABIKind Kind,bool SoftFloatABI)4889   PPC64_SVR4_ABIInfo(CodeGen::CodeGenTypes &CGT, ABIKind Kind,
4890                      bool SoftFloatABI)
4891       : SwiftABIInfo(CGT), Kind(Kind), IsSoftFloatABI(SoftFloatABI) {}
4892 
4893   bool isPromotableTypeForABI(QualType Ty) const;
4894   CharUnits getParamTypeAlignment(QualType Ty) const;
4895 
4896   ABIArgInfo classifyReturnType(QualType RetTy) const;
4897   ABIArgInfo classifyArgumentType(QualType Ty) const;
4898 
4899   bool isHomogeneousAggregateBaseType(QualType Ty) const override;
4900   bool isHomogeneousAggregateSmallEnough(const Type *Ty,
4901                                          uint64_t Members) const override;
4902 
4903   // TODO: We can add more logic to computeInfo to improve performance.
4904   // Example: For aggregate arguments that fit in a register, we could
4905   // use getDirectInReg (as is done below for structs containing a single
4906   // floating-point value) to avoid pushing them to memory on function
4907   // entry.  This would require changing the logic in PPCISelLowering
4908   // when lowering the parameters in the caller and args in the callee.
computeInfo(CGFunctionInfo & FI) const4909   void computeInfo(CGFunctionInfo &FI) const override {
4910     if (!getCXXABI().classifyReturnType(FI))
4911       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
4912     for (auto &I : FI.arguments()) {
4913       // We rely on the default argument classification for the most part.
4914       // One exception:  An aggregate containing a single floating-point
4915       // or vector item must be passed in a register if one is available.
4916       const Type *T = isSingleElementStruct(I.type, getContext());
4917       if (T) {
4918         const BuiltinType *BT = T->getAs<BuiltinType>();
4919         if ((T->isVectorType() && getContext().getTypeSize(T) == 128) ||
4920             (BT && BT->isFloatingPoint())) {
4921           QualType QT(T, 0);
4922           I.info = ABIArgInfo::getDirectInReg(CGT.ConvertType(QT));
4923           continue;
4924         }
4925       }
4926       I.info = classifyArgumentType(I.type);
4927     }
4928   }
4929 
4930   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
4931                     QualType Ty) const override;
4932 
shouldPassIndirectlyForSwift(ArrayRef<llvm::Type * > scalars,bool asReturnValue) const4933   bool shouldPassIndirectlyForSwift(ArrayRef<llvm::Type*> scalars,
4934                                     bool asReturnValue) const override {
4935     return occupiesMoreThan(CGT, scalars, /*total*/ 4);
4936   }
4937 
isSwiftErrorInRegister() const4938   bool isSwiftErrorInRegister() const override {
4939     return false;
4940   }
4941 };
4942 
4943 class PPC64_SVR4_TargetCodeGenInfo : public TargetCodeGenInfo {
4944 
4945 public:
PPC64_SVR4_TargetCodeGenInfo(CodeGenTypes & CGT,PPC64_SVR4_ABIInfo::ABIKind Kind,bool SoftFloatABI)4946   PPC64_SVR4_TargetCodeGenInfo(CodeGenTypes &CGT,
4947                                PPC64_SVR4_ABIInfo::ABIKind Kind,
4948                                bool SoftFloatABI)
4949       : TargetCodeGenInfo(
4950             std::make_unique<PPC64_SVR4_ABIInfo>(CGT, Kind, SoftFloatABI)) {}
4951 
getDwarfEHStackPointer(CodeGen::CodeGenModule & M) const4952   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
4953     // This is recovered from gcc output.
4954     return 1; // r1 is the dedicated stack pointer
4955   }
4956 
4957   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
4958                                llvm::Value *Address) const override;
4959 };
4960 
4961 class PPC64TargetCodeGenInfo : public DefaultTargetCodeGenInfo {
4962 public:
PPC64TargetCodeGenInfo(CodeGenTypes & CGT)4963   PPC64TargetCodeGenInfo(CodeGenTypes &CGT) : DefaultTargetCodeGenInfo(CGT) {}
4964 
getDwarfEHStackPointer(CodeGen::CodeGenModule & M) const4965   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
4966     // This is recovered from gcc output.
4967     return 1; // r1 is the dedicated stack pointer
4968   }
4969 
4970   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
4971                                llvm::Value *Address) const override;
4972 };
4973 
4974 }
4975 
4976 // Return true if the ABI requires Ty to be passed sign- or zero-
4977 // extended to 64 bits.
4978 bool
isPromotableTypeForABI(QualType Ty) const4979 PPC64_SVR4_ABIInfo::isPromotableTypeForABI(QualType Ty) const {
4980   // Treat an enum type as its underlying type.
4981   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
4982     Ty = EnumTy->getDecl()->getIntegerType();
4983 
4984   // Promotable integer types are required to be promoted by the ABI.
4985   if (isPromotableIntegerTypeForABI(Ty))
4986     return true;
4987 
4988   // In addition to the usual promotable integer types, we also need to
4989   // extend all 32-bit types, since the ABI requires promotion to 64 bits.
4990   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
4991     switch (BT->getKind()) {
4992     case BuiltinType::Int:
4993     case BuiltinType::UInt:
4994       return true;
4995     default:
4996       break;
4997     }
4998 
4999   if (const auto *EIT = Ty->getAs<ExtIntType>())
5000     if (EIT->getNumBits() < 64)
5001       return true;
5002 
5003   return false;
5004 }
5005 
5006 /// isAlignedParamType - Determine whether a type requires 16-byte or
5007 /// higher alignment in the parameter area.  Always returns at least 8.
getParamTypeAlignment(QualType Ty) const5008 CharUnits PPC64_SVR4_ABIInfo::getParamTypeAlignment(QualType Ty) const {
5009   // Complex types are passed just like their elements.
5010   if (const ComplexType *CTy = Ty->getAs<ComplexType>())
5011     Ty = CTy->getElementType();
5012 
5013   // Only vector types of size 16 bytes need alignment (larger types are
5014   // passed via reference, smaller types are not aligned).
5015   if (Ty->isVectorType()) {
5016     return CharUnits::fromQuantity(getContext().getTypeSize(Ty) == 128 ? 16 : 8);
5017   } else if (Ty->isRealFloatingType() &&
5018              &getContext().getFloatTypeSemantics(Ty) ==
5019                  &llvm::APFloat::IEEEquad()) {
5020     // According to ABI document section 'Optional Save Areas': If extended
5021     // precision floating-point values in IEEE BINARY 128 QUADRUPLE PRECISION
5022     // format are supported, map them to a single quadword, quadword aligned.
5023     return CharUnits::fromQuantity(16);
5024   }
5025 
5026   // For single-element float/vector structs, we consider the whole type
5027   // to have the same alignment requirements as its single element.
5028   const Type *AlignAsType = nullptr;
5029   const Type *EltType = isSingleElementStruct(Ty, getContext());
5030   if (EltType) {
5031     const BuiltinType *BT = EltType->getAs<BuiltinType>();
5032     if ((EltType->isVectorType() && getContext().getTypeSize(EltType) == 128) ||
5033         (BT && BT->isFloatingPoint()))
5034       AlignAsType = EltType;
5035   }
5036 
5037   // Likewise for ELFv2 homogeneous aggregates.
5038   const Type *Base = nullptr;
5039   uint64_t Members = 0;
5040   if (!AlignAsType && Kind == ELFv2 &&
5041       isAggregateTypeForABI(Ty) && isHomogeneousAggregate(Ty, Base, Members))
5042     AlignAsType = Base;
5043 
5044   // With special case aggregates, only vector base types need alignment.
5045   if (AlignAsType) {
5046     return CharUnits::fromQuantity(AlignAsType->isVectorType() ? 16 : 8);
5047   }
5048 
5049   // Otherwise, we only need alignment for any aggregate type that
5050   // has an alignment requirement of >= 16 bytes.
5051   if (isAggregateTypeForABI(Ty) && getContext().getTypeAlign(Ty) >= 128) {
5052     return CharUnits::fromQuantity(16);
5053   }
5054 
5055   return CharUnits::fromQuantity(8);
5056 }
5057 
5058 /// isHomogeneousAggregate - Return true if a type is an ELFv2 homogeneous
5059 /// aggregate.  Base is set to the base element type, and Members is set
5060 /// to the number of base elements.
isHomogeneousAggregate(QualType Ty,const Type * & Base,uint64_t & Members) const5061 bool ABIInfo::isHomogeneousAggregate(QualType Ty, const Type *&Base,
5062                                      uint64_t &Members) const {
5063   if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) {
5064     uint64_t NElements = AT->getSize().getZExtValue();
5065     if (NElements == 0)
5066       return false;
5067     if (!isHomogeneousAggregate(AT->getElementType(), Base, Members))
5068       return false;
5069     Members *= NElements;
5070   } else if (const RecordType *RT = Ty->getAs<RecordType>()) {
5071     const RecordDecl *RD = RT->getDecl();
5072     if (RD->hasFlexibleArrayMember())
5073       return false;
5074 
5075     Members = 0;
5076 
5077     // If this is a C++ record, check the properties of the record such as
5078     // bases and ABI specific restrictions
5079     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
5080       if (!getCXXABI().isPermittedToBeHomogeneousAggregate(CXXRD))
5081         return false;
5082 
5083       for (const auto &I : CXXRD->bases()) {
5084         // Ignore empty records.
5085         if (isEmptyRecord(getContext(), I.getType(), true))
5086           continue;
5087 
5088         uint64_t FldMembers;
5089         if (!isHomogeneousAggregate(I.getType(), Base, FldMembers))
5090           return false;
5091 
5092         Members += FldMembers;
5093       }
5094     }
5095 
5096     for (const auto *FD : RD->fields()) {
5097       // Ignore (non-zero arrays of) empty records.
5098       QualType FT = FD->getType();
5099       while (const ConstantArrayType *AT =
5100              getContext().getAsConstantArrayType(FT)) {
5101         if (AT->getSize().getZExtValue() == 0)
5102           return false;
5103         FT = AT->getElementType();
5104       }
5105       if (isEmptyRecord(getContext(), FT, true))
5106         continue;
5107 
5108       // For compatibility with GCC, ignore empty bitfields in C++ mode.
5109       if (getContext().getLangOpts().CPlusPlus &&
5110           FD->isZeroLengthBitField(getContext()))
5111         continue;
5112 
5113       uint64_t FldMembers;
5114       if (!isHomogeneousAggregate(FD->getType(), Base, FldMembers))
5115         return false;
5116 
5117       Members = (RD->isUnion() ?
5118                  std::max(Members, FldMembers) : Members + FldMembers);
5119     }
5120 
5121     if (!Base)
5122       return false;
5123 
5124     // Ensure there is no padding.
5125     if (getContext().getTypeSize(Base) * Members !=
5126         getContext().getTypeSize(Ty))
5127       return false;
5128   } else {
5129     Members = 1;
5130     if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
5131       Members = 2;
5132       Ty = CT->getElementType();
5133     }
5134 
5135     // Most ABIs only support float, double, and some vector type widths.
5136     if (!isHomogeneousAggregateBaseType(Ty))
5137       return false;
5138 
5139     // The base type must be the same for all members.  Types that
5140     // agree in both total size and mode (float vs. vector) are
5141     // treated as being equivalent here.
5142     const Type *TyPtr = Ty.getTypePtr();
5143     if (!Base) {
5144       Base = TyPtr;
5145       // If it's a non-power-of-2 vector, its size is already a power-of-2,
5146       // so make sure to widen it explicitly.
5147       if (const VectorType *VT = Base->getAs<VectorType>()) {
5148         QualType EltTy = VT->getElementType();
5149         unsigned NumElements =
5150             getContext().getTypeSize(VT) / getContext().getTypeSize(EltTy);
5151         Base = getContext()
5152                    .getVectorType(EltTy, NumElements, VT->getVectorKind())
5153                    .getTypePtr();
5154       }
5155     }
5156 
5157     if (Base->isVectorType() != TyPtr->isVectorType() ||
5158         getContext().getTypeSize(Base) != getContext().getTypeSize(TyPtr))
5159       return false;
5160   }
5161   return Members > 0 && isHomogeneousAggregateSmallEnough(Base, Members);
5162 }
5163 
isHomogeneousAggregateBaseType(QualType Ty) const5164 bool PPC64_SVR4_ABIInfo::isHomogeneousAggregateBaseType(QualType Ty) const {
5165   // Homogeneous aggregates for ELFv2 must have base types of float,
5166   // double, long double, or 128-bit vectors.
5167   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
5168     if (BT->getKind() == BuiltinType::Float ||
5169         BT->getKind() == BuiltinType::Double ||
5170         BT->getKind() == BuiltinType::LongDouble ||
5171         (getContext().getTargetInfo().hasFloat128Type() &&
5172           (BT->getKind() == BuiltinType::Float128))) {
5173       if (IsSoftFloatABI)
5174         return false;
5175       return true;
5176     }
5177   }
5178   if (const VectorType *VT = Ty->getAs<VectorType>()) {
5179     if (getContext().getTypeSize(VT) == 128)
5180       return true;
5181   }
5182   return false;
5183 }
5184 
isHomogeneousAggregateSmallEnough(const Type * Base,uint64_t Members) const5185 bool PPC64_SVR4_ABIInfo::isHomogeneousAggregateSmallEnough(
5186     const Type *Base, uint64_t Members) const {
5187   // Vector and fp128 types require one register, other floating point types
5188   // require one or two registers depending on their size.
5189   uint32_t NumRegs =
5190       ((getContext().getTargetInfo().hasFloat128Type() &&
5191           Base->isFloat128Type()) ||
5192         Base->isVectorType()) ? 1
5193                               : (getContext().getTypeSize(Base) + 63) / 64;
5194 
5195   // Homogeneous Aggregates may occupy at most 8 registers.
5196   return Members * NumRegs <= 8;
5197 }
5198 
5199 ABIArgInfo
classifyArgumentType(QualType Ty) const5200 PPC64_SVR4_ABIInfo::classifyArgumentType(QualType Ty) const {
5201   Ty = useFirstFieldIfTransparentUnion(Ty);
5202 
5203   if (Ty->isAnyComplexType())
5204     return ABIArgInfo::getDirect();
5205 
5206   // Non-Altivec vector types are passed in GPRs (smaller than 16 bytes)
5207   // or via reference (larger than 16 bytes).
5208   if (Ty->isVectorType()) {
5209     uint64_t Size = getContext().getTypeSize(Ty);
5210     if (Size > 128)
5211       return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
5212     else if (Size < 128) {
5213       llvm::Type *CoerceTy = llvm::IntegerType::get(getVMContext(), Size);
5214       return ABIArgInfo::getDirect(CoerceTy);
5215     }
5216   }
5217 
5218   if (const auto *EIT = Ty->getAs<ExtIntType>())
5219     if (EIT->getNumBits() > 128)
5220       return getNaturalAlignIndirect(Ty, /*ByVal=*/true);
5221 
5222   if (isAggregateTypeForABI(Ty)) {
5223     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
5224       return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
5225 
5226     uint64_t ABIAlign = getParamTypeAlignment(Ty).getQuantity();
5227     uint64_t TyAlign = getContext().getTypeAlignInChars(Ty).getQuantity();
5228 
5229     // ELFv2 homogeneous aggregates are passed as array types.
5230     const Type *Base = nullptr;
5231     uint64_t Members = 0;
5232     if (Kind == ELFv2 &&
5233         isHomogeneousAggregate(Ty, Base, Members)) {
5234       llvm::Type *BaseTy = CGT.ConvertType(QualType(Base, 0));
5235       llvm::Type *CoerceTy = llvm::ArrayType::get(BaseTy, Members);
5236       return ABIArgInfo::getDirect(CoerceTy);
5237     }
5238 
5239     // If an aggregate may end up fully in registers, we do not
5240     // use the ByVal method, but pass the aggregate as array.
5241     // This is usually beneficial since we avoid forcing the
5242     // back-end to store the argument to memory.
5243     uint64_t Bits = getContext().getTypeSize(Ty);
5244     if (Bits > 0 && Bits <= 8 * GPRBits) {
5245       llvm::Type *CoerceTy;
5246 
5247       // Types up to 8 bytes are passed as integer type (which will be
5248       // properly aligned in the argument save area doubleword).
5249       if (Bits <= GPRBits)
5250         CoerceTy =
5251             llvm::IntegerType::get(getVMContext(), llvm::alignTo(Bits, 8));
5252       // Larger types are passed as arrays, with the base type selected
5253       // according to the required alignment in the save area.
5254       else {
5255         uint64_t RegBits = ABIAlign * 8;
5256         uint64_t NumRegs = llvm::alignTo(Bits, RegBits) / RegBits;
5257         llvm::Type *RegTy = llvm::IntegerType::get(getVMContext(), RegBits);
5258         CoerceTy = llvm::ArrayType::get(RegTy, NumRegs);
5259       }
5260 
5261       return ABIArgInfo::getDirect(CoerceTy);
5262     }
5263 
5264     // All other aggregates are passed ByVal.
5265     return ABIArgInfo::getIndirect(CharUnits::fromQuantity(ABIAlign),
5266                                    /*ByVal=*/true,
5267                                    /*Realign=*/TyAlign > ABIAlign);
5268   }
5269 
5270   return (isPromotableTypeForABI(Ty) ? ABIArgInfo::getExtend(Ty)
5271                                      : ABIArgInfo::getDirect());
5272 }
5273 
5274 ABIArgInfo
classifyReturnType(QualType RetTy) const5275 PPC64_SVR4_ABIInfo::classifyReturnType(QualType RetTy) const {
5276   if (RetTy->isVoidType())
5277     return ABIArgInfo::getIgnore();
5278 
5279   if (RetTy->isAnyComplexType())
5280     return ABIArgInfo::getDirect();
5281 
5282   // Non-Altivec vector types are returned in GPRs (smaller than 16 bytes)
5283   // or via reference (larger than 16 bytes).
5284   if (RetTy->isVectorType()) {
5285     uint64_t Size = getContext().getTypeSize(RetTy);
5286     if (Size > 128)
5287       return getNaturalAlignIndirect(RetTy);
5288     else if (Size < 128) {
5289       llvm::Type *CoerceTy = llvm::IntegerType::get(getVMContext(), Size);
5290       return ABIArgInfo::getDirect(CoerceTy);
5291     }
5292   }
5293 
5294   if (const auto *EIT = RetTy->getAs<ExtIntType>())
5295     if (EIT->getNumBits() > 128)
5296       return getNaturalAlignIndirect(RetTy, /*ByVal=*/false);
5297 
5298   if (isAggregateTypeForABI(RetTy)) {
5299     // ELFv2 homogeneous aggregates are returned as array types.
5300     const Type *Base = nullptr;
5301     uint64_t Members = 0;
5302     if (Kind == ELFv2 &&
5303         isHomogeneousAggregate(RetTy, Base, Members)) {
5304       llvm::Type *BaseTy = CGT.ConvertType(QualType(Base, 0));
5305       llvm::Type *CoerceTy = llvm::ArrayType::get(BaseTy, Members);
5306       return ABIArgInfo::getDirect(CoerceTy);
5307     }
5308 
5309     // ELFv2 small aggregates are returned in up to two registers.
5310     uint64_t Bits = getContext().getTypeSize(RetTy);
5311     if (Kind == ELFv2 && Bits <= 2 * GPRBits) {
5312       if (Bits == 0)
5313         return ABIArgInfo::getIgnore();
5314 
5315       llvm::Type *CoerceTy;
5316       if (Bits > GPRBits) {
5317         CoerceTy = llvm::IntegerType::get(getVMContext(), GPRBits);
5318         CoerceTy = llvm::StructType::get(CoerceTy, CoerceTy);
5319       } else
5320         CoerceTy =
5321             llvm::IntegerType::get(getVMContext(), llvm::alignTo(Bits, 8));
5322       return ABIArgInfo::getDirect(CoerceTy);
5323     }
5324 
5325     // All other aggregates are returned indirectly.
5326     return getNaturalAlignIndirect(RetTy);
5327   }
5328 
5329   return (isPromotableTypeForABI(RetTy) ? ABIArgInfo::getExtend(RetTy)
5330                                         : ABIArgInfo::getDirect());
5331 }
5332 
5333 // Based on ARMABIInfo::EmitVAArg, adjusted for 64-bit machine.
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const5334 Address PPC64_SVR4_ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
5335                                       QualType Ty) const {
5336   auto TypeInfo = getContext().getTypeInfoInChars(Ty);
5337   TypeInfo.Align = getParamTypeAlignment(Ty);
5338 
5339   CharUnits SlotSize = CharUnits::fromQuantity(8);
5340 
5341   // If we have a complex type and the base type is smaller than 8 bytes,
5342   // the ABI calls for the real and imaginary parts to be right-adjusted
5343   // in separate doublewords.  However, Clang expects us to produce a
5344   // pointer to a structure with the two parts packed tightly.  So generate
5345   // loads of the real and imaginary parts relative to the va_list pointer,
5346   // and store them to a temporary structure.
5347   if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
5348     CharUnits EltSize = TypeInfo.Width / 2;
5349     if (EltSize < SlotSize) {
5350       Address Addr = emitVoidPtrDirectVAArg(CGF, VAListAddr, CGF.Int8Ty,
5351                                             SlotSize * 2, SlotSize,
5352                                             SlotSize, /*AllowHigher*/ true);
5353 
5354       Address RealAddr = Addr;
5355       Address ImagAddr = RealAddr;
5356       if (CGF.CGM.getDataLayout().isBigEndian()) {
5357         RealAddr = CGF.Builder.CreateConstInBoundsByteGEP(RealAddr,
5358                                                           SlotSize - EltSize);
5359         ImagAddr = CGF.Builder.CreateConstInBoundsByteGEP(ImagAddr,
5360                                                       2 * SlotSize - EltSize);
5361       } else {
5362         ImagAddr = CGF.Builder.CreateConstInBoundsByteGEP(RealAddr, SlotSize);
5363       }
5364 
5365       llvm::Type *EltTy = CGF.ConvertTypeForMem(CTy->getElementType());
5366       RealAddr = CGF.Builder.CreateElementBitCast(RealAddr, EltTy);
5367       ImagAddr = CGF.Builder.CreateElementBitCast(ImagAddr, EltTy);
5368       llvm::Value *Real = CGF.Builder.CreateLoad(RealAddr, ".vareal");
5369       llvm::Value *Imag = CGF.Builder.CreateLoad(ImagAddr, ".vaimag");
5370 
5371       Address Temp = CGF.CreateMemTemp(Ty, "vacplx");
5372       CGF.EmitStoreOfComplex({Real, Imag}, CGF.MakeAddrLValue(Temp, Ty),
5373                              /*init*/ true);
5374       return Temp;
5375     }
5376   }
5377 
5378   // Otherwise, just use the general rule.
5379   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*Indirect*/ false,
5380                           TypeInfo, SlotSize, /*AllowHigher*/ true);
5381 }
5382 
5383 bool
initDwarfEHRegSizeTable(CodeGen::CodeGenFunction & CGF,llvm::Value * Address) const5384 PPC64_SVR4_TargetCodeGenInfo::initDwarfEHRegSizeTable(
5385   CodeGen::CodeGenFunction &CGF,
5386   llvm::Value *Address) const {
5387   return PPC_initDwarfEHRegSizeTable(CGF, Address, /*Is64Bit*/ true,
5388                                      /*IsAIX*/ false);
5389 }
5390 
5391 bool
initDwarfEHRegSizeTable(CodeGen::CodeGenFunction & CGF,llvm::Value * Address) const5392 PPC64TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
5393                                                 llvm::Value *Address) const {
5394   return PPC_initDwarfEHRegSizeTable(CGF, Address, /*Is64Bit*/ true,
5395                                      /*IsAIX*/ false);
5396 }
5397 
5398 //===----------------------------------------------------------------------===//
5399 // AArch64 ABI Implementation
5400 //===----------------------------------------------------------------------===//
5401 
5402 namespace {
5403 
5404 class AArch64ABIInfo : public SwiftABIInfo {
5405 public:
5406   enum ABIKind {
5407     AAPCS = 0,
5408     DarwinPCS,
5409     Win64
5410   };
5411 
5412 private:
5413   ABIKind Kind;
5414 
5415 public:
AArch64ABIInfo(CodeGenTypes & CGT,ABIKind Kind)5416   AArch64ABIInfo(CodeGenTypes &CGT, ABIKind Kind)
5417     : SwiftABIInfo(CGT), Kind(Kind) {}
5418 
5419 private:
getABIKind() const5420   ABIKind getABIKind() const { return Kind; }
isDarwinPCS() const5421   bool isDarwinPCS() const { return Kind == DarwinPCS; }
5422 
5423   ABIArgInfo classifyReturnType(QualType RetTy, bool IsVariadic) const;
5424   ABIArgInfo classifyArgumentType(QualType RetTy, bool IsVariadic,
5425                                   unsigned CallingConvention) const;
5426   ABIArgInfo coerceIllegalVector(QualType Ty) const;
5427   bool isHomogeneousAggregateBaseType(QualType Ty) const override;
5428   bool isHomogeneousAggregateSmallEnough(const Type *Ty,
5429                                          uint64_t Members) const override;
5430 
5431   bool isIllegalVectorType(QualType Ty) const;
5432 
computeInfo(CGFunctionInfo & FI) const5433   void computeInfo(CGFunctionInfo &FI) const override {
5434     if (!::classifyReturnType(getCXXABI(), FI, *this))
5435       FI.getReturnInfo() =
5436           classifyReturnType(FI.getReturnType(), FI.isVariadic());
5437 
5438     for (auto &it : FI.arguments())
5439       it.info = classifyArgumentType(it.type, FI.isVariadic(),
5440                                      FI.getCallingConvention());
5441   }
5442 
5443   Address EmitDarwinVAArg(Address VAListAddr, QualType Ty,
5444                           CodeGenFunction &CGF) const;
5445 
5446   Address EmitAAPCSVAArg(Address VAListAddr, QualType Ty,
5447                          CodeGenFunction &CGF) const;
5448 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const5449   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
5450                     QualType Ty) const override {
5451     llvm::Type *BaseTy = CGF.ConvertType(Ty);
5452     if (isa<llvm::ScalableVectorType>(BaseTy))
5453       llvm::report_fatal_error("Passing SVE types to variadic functions is "
5454                                "currently not supported");
5455 
5456     return Kind == Win64 ? EmitMSVAArg(CGF, VAListAddr, Ty)
5457                          : isDarwinPCS() ? EmitDarwinVAArg(VAListAddr, Ty, CGF)
5458                                          : EmitAAPCSVAArg(VAListAddr, Ty, CGF);
5459   }
5460 
5461   Address EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
5462                       QualType Ty) const override;
5463 
shouldPassIndirectlyForSwift(ArrayRef<llvm::Type * > scalars,bool asReturnValue) const5464   bool shouldPassIndirectlyForSwift(ArrayRef<llvm::Type*> scalars,
5465                                     bool asReturnValue) const override {
5466     return occupiesMoreThan(CGT, scalars, /*total*/ 4);
5467   }
isSwiftErrorInRegister() const5468   bool isSwiftErrorInRegister() const override {
5469     return true;
5470   }
5471 
5472   bool isLegalVectorTypeForSwift(CharUnits totalSize, llvm::Type *eltTy,
5473                                  unsigned elts) const override;
5474 
allowBFloatArgsAndRet() const5475   bool allowBFloatArgsAndRet() const override {
5476     return getTarget().hasBFloat16Type();
5477   }
5478 };
5479 
5480 class AArch64TargetCodeGenInfo : public TargetCodeGenInfo {
5481 public:
AArch64TargetCodeGenInfo(CodeGenTypes & CGT,AArch64ABIInfo::ABIKind Kind)5482   AArch64TargetCodeGenInfo(CodeGenTypes &CGT, AArch64ABIInfo::ABIKind Kind)
5483       : TargetCodeGenInfo(std::make_unique<AArch64ABIInfo>(CGT, Kind)) {}
5484 
getARCRetainAutoreleasedReturnValueMarker() const5485   StringRef getARCRetainAutoreleasedReturnValueMarker() const override {
5486     return "mov\tfp, fp\t\t// marker for objc_retainAutoreleaseReturnValue";
5487   }
5488 
getDwarfEHStackPointer(CodeGen::CodeGenModule & M) const5489   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
5490     return 31;
5491   }
5492 
doesReturnSlotInterfereWithArgs() const5493   bool doesReturnSlotInterfereWithArgs() const override { return false; }
5494 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & CGM) const5495   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
5496                            CodeGen::CodeGenModule &CGM) const override {
5497     const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
5498     if (!FD)
5499       return;
5500 
5501     const auto *TA = FD->getAttr<TargetAttr>();
5502     if (TA == nullptr)
5503       return;
5504 
5505     ParsedTargetAttr Attr = TA->parse();
5506     if (Attr.BranchProtection.empty())
5507       return;
5508 
5509     TargetInfo::BranchProtectionInfo BPI;
5510     StringRef Error;
5511     (void)CGM.getTarget().validateBranchProtection(Attr.BranchProtection,
5512                                                    BPI, Error);
5513     assert(Error.empty());
5514 
5515     auto *Fn = cast<llvm::Function>(GV);
5516     static const char *SignReturnAddrStr[] = {"none", "non-leaf", "all"};
5517     Fn->addFnAttr("sign-return-address", SignReturnAddrStr[static_cast<int>(BPI.SignReturnAddr)]);
5518 
5519     if (BPI.SignReturnAddr != LangOptions::SignReturnAddressScopeKind::None) {
5520       Fn->addFnAttr("sign-return-address-key",
5521                     BPI.SignKey == LangOptions::SignReturnAddressKeyKind::AKey
5522                         ? "a_key"
5523                         : "b_key");
5524     }
5525 
5526     Fn->addFnAttr("branch-target-enforcement",
5527                   BPI.BranchTargetEnforcement ? "true" : "false");
5528   }
5529 
isScalarizableAsmOperand(CodeGen::CodeGenFunction & CGF,llvm::Type * Ty) const5530   bool isScalarizableAsmOperand(CodeGen::CodeGenFunction &CGF,
5531                                 llvm::Type *Ty) const override {
5532     if (CGF.getTarget().hasFeature("ls64")) {
5533       auto *ST = dyn_cast<llvm::StructType>(Ty);
5534       if (ST && ST->getNumElements() == 1) {
5535         auto *AT = dyn_cast<llvm::ArrayType>(ST->getElementType(0));
5536         if (AT && AT->getNumElements() == 8 &&
5537             AT->getElementType()->isIntegerTy(64))
5538           return true;
5539       }
5540     }
5541     return TargetCodeGenInfo::isScalarizableAsmOperand(CGF, Ty);
5542   }
5543 };
5544 
5545 class WindowsAArch64TargetCodeGenInfo : public AArch64TargetCodeGenInfo {
5546 public:
WindowsAArch64TargetCodeGenInfo(CodeGenTypes & CGT,AArch64ABIInfo::ABIKind K)5547   WindowsAArch64TargetCodeGenInfo(CodeGenTypes &CGT, AArch64ABIInfo::ABIKind K)
5548       : AArch64TargetCodeGenInfo(CGT, K) {}
5549 
5550   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
5551                            CodeGen::CodeGenModule &CGM) const override;
5552 
getDependentLibraryOption(llvm::StringRef Lib,llvm::SmallString<24> & Opt) const5553   void getDependentLibraryOption(llvm::StringRef Lib,
5554                                  llvm::SmallString<24> &Opt) const override {
5555     Opt = "/DEFAULTLIB:" + qualifyWindowsLibrary(Lib);
5556   }
5557 
getDetectMismatchOption(llvm::StringRef Name,llvm::StringRef Value,llvm::SmallString<32> & Opt) const5558   void getDetectMismatchOption(llvm::StringRef Name, llvm::StringRef Value,
5559                                llvm::SmallString<32> &Opt) const override {
5560     Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
5561   }
5562 };
5563 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & CGM) const5564 void WindowsAArch64TargetCodeGenInfo::setTargetAttributes(
5565     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &CGM) const {
5566   AArch64TargetCodeGenInfo::setTargetAttributes(D, GV, CGM);
5567   if (GV->isDeclaration())
5568     return;
5569   addStackProbeTargetAttributes(D, GV, CGM);
5570 }
5571 }
5572 
coerceIllegalVector(QualType Ty) const5573 ABIArgInfo AArch64ABIInfo::coerceIllegalVector(QualType Ty) const {
5574   assert(Ty->isVectorType() && "expected vector type!");
5575 
5576   const auto *VT = Ty->castAs<VectorType>();
5577   if (VT->getVectorKind() == VectorType::SveFixedLengthPredicateVector) {
5578     assert(VT->getElementType()->isBuiltinType() && "expected builtin type!");
5579     assert(VT->getElementType()->castAs<BuiltinType>()->getKind() ==
5580                BuiltinType::UChar &&
5581            "unexpected builtin type for SVE predicate!");
5582     return ABIArgInfo::getDirect(llvm::ScalableVectorType::get(
5583         llvm::Type::getInt1Ty(getVMContext()), 16));
5584   }
5585 
5586   if (VT->getVectorKind() == VectorType::SveFixedLengthDataVector) {
5587     assert(VT->getElementType()->isBuiltinType() && "expected builtin type!");
5588 
5589     const auto *BT = VT->getElementType()->castAs<BuiltinType>();
5590     llvm::ScalableVectorType *ResType = nullptr;
5591     switch (BT->getKind()) {
5592     default:
5593       llvm_unreachable("unexpected builtin type for SVE vector!");
5594     case BuiltinType::SChar:
5595     case BuiltinType::UChar:
5596       ResType = llvm::ScalableVectorType::get(
5597           llvm::Type::getInt8Ty(getVMContext()), 16);
5598       break;
5599     case BuiltinType::Short:
5600     case BuiltinType::UShort:
5601       ResType = llvm::ScalableVectorType::get(
5602           llvm::Type::getInt16Ty(getVMContext()), 8);
5603       break;
5604     case BuiltinType::Int:
5605     case BuiltinType::UInt:
5606       ResType = llvm::ScalableVectorType::get(
5607           llvm::Type::getInt32Ty(getVMContext()), 4);
5608       break;
5609     case BuiltinType::Long:
5610     case BuiltinType::ULong:
5611       ResType = llvm::ScalableVectorType::get(
5612           llvm::Type::getInt64Ty(getVMContext()), 2);
5613       break;
5614     case BuiltinType::Half:
5615       ResType = llvm::ScalableVectorType::get(
5616           llvm::Type::getHalfTy(getVMContext()), 8);
5617       break;
5618     case BuiltinType::Float:
5619       ResType = llvm::ScalableVectorType::get(
5620           llvm::Type::getFloatTy(getVMContext()), 4);
5621       break;
5622     case BuiltinType::Double:
5623       ResType = llvm::ScalableVectorType::get(
5624           llvm::Type::getDoubleTy(getVMContext()), 2);
5625       break;
5626     case BuiltinType::BFloat16:
5627       ResType = llvm::ScalableVectorType::get(
5628           llvm::Type::getBFloatTy(getVMContext()), 8);
5629       break;
5630     }
5631     return ABIArgInfo::getDirect(ResType);
5632   }
5633 
5634   uint64_t Size = getContext().getTypeSize(Ty);
5635   // Android promotes <2 x i8> to i16, not i32
5636   if (isAndroid() && (Size <= 16)) {
5637     llvm::Type *ResType = llvm::Type::getInt16Ty(getVMContext());
5638     return ABIArgInfo::getDirect(ResType);
5639   }
5640   if (Size <= 32) {
5641     llvm::Type *ResType = llvm::Type::getInt32Ty(getVMContext());
5642     return ABIArgInfo::getDirect(ResType);
5643   }
5644   if (Size == 64) {
5645     auto *ResType =
5646         llvm::FixedVectorType::get(llvm::Type::getInt32Ty(getVMContext()), 2);
5647     return ABIArgInfo::getDirect(ResType);
5648   }
5649   if (Size == 128) {
5650     auto *ResType =
5651         llvm::FixedVectorType::get(llvm::Type::getInt32Ty(getVMContext()), 4);
5652     return ABIArgInfo::getDirect(ResType);
5653   }
5654   return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
5655 }
5656 
5657 ABIArgInfo
classifyArgumentType(QualType Ty,bool IsVariadic,unsigned CallingConvention) const5658 AArch64ABIInfo::classifyArgumentType(QualType Ty, bool IsVariadic,
5659                                      unsigned CallingConvention) const {
5660   Ty = useFirstFieldIfTransparentUnion(Ty);
5661 
5662   // Handle illegal vector types here.
5663   if (isIllegalVectorType(Ty))
5664     return coerceIllegalVector(Ty);
5665 
5666   if (!isAggregateTypeForABI(Ty)) {
5667     // Treat an enum type as its underlying type.
5668     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
5669       Ty = EnumTy->getDecl()->getIntegerType();
5670 
5671     if (const auto *EIT = Ty->getAs<ExtIntType>())
5672       if (EIT->getNumBits() > 128)
5673         return getNaturalAlignIndirect(Ty);
5674 
5675     return (isPromotableIntegerTypeForABI(Ty) && isDarwinPCS()
5676                 ? ABIArgInfo::getExtend(Ty)
5677                 : ABIArgInfo::getDirect());
5678   }
5679 
5680   // Structures with either a non-trivial destructor or a non-trivial
5681   // copy constructor are always indirect.
5682   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
5683     return getNaturalAlignIndirect(Ty, /*ByVal=*/RAA ==
5684                                      CGCXXABI::RAA_DirectInMemory);
5685   }
5686 
5687   // Empty records are always ignored on Darwin, but actually passed in C++ mode
5688   // elsewhere for GNU compatibility.
5689   uint64_t Size = getContext().getTypeSize(Ty);
5690   bool IsEmpty = isEmptyRecord(getContext(), Ty, true);
5691   if (IsEmpty || Size == 0) {
5692     if (!getContext().getLangOpts().CPlusPlus || isDarwinPCS())
5693       return ABIArgInfo::getIgnore();
5694 
5695     // GNU C mode. The only argument that gets ignored is an empty one with size
5696     // 0.
5697     if (IsEmpty && Size == 0)
5698       return ABIArgInfo::getIgnore();
5699     return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
5700   }
5701 
5702   // Homogeneous Floating-point Aggregates (HFAs) need to be expanded.
5703   const Type *Base = nullptr;
5704   uint64_t Members = 0;
5705   bool IsWin64 = Kind == Win64 || CallingConvention == llvm::CallingConv::Win64;
5706   bool IsWinVariadic = IsWin64 && IsVariadic;
5707   // In variadic functions on Windows, all composite types are treated alike,
5708   // no special handling of HFAs/HVAs.
5709   if (!IsWinVariadic && isHomogeneousAggregate(Ty, Base, Members)) {
5710     if (Kind != AArch64ABIInfo::AAPCS)
5711       return ABIArgInfo::getDirect(
5712           llvm::ArrayType::get(CGT.ConvertType(QualType(Base, 0)), Members));
5713 
5714     // For alignment adjusted HFAs, cap the argument alignment to 16, leave it
5715     // default otherwise.
5716     unsigned Align =
5717         getContext().getTypeUnadjustedAlignInChars(Ty).getQuantity();
5718     unsigned BaseAlign = getContext().getTypeAlignInChars(Base).getQuantity();
5719     Align = (Align > BaseAlign && Align >= 16) ? 16 : 0;
5720     return ABIArgInfo::getDirect(
5721         llvm::ArrayType::get(CGT.ConvertType(QualType(Base, 0)), Members), 0,
5722         nullptr, true, Align);
5723   }
5724 
5725   // Aggregates <= 16 bytes are passed directly in registers or on the stack.
5726   if (Size <= 128) {
5727     // On RenderScript, coerce Aggregates <= 16 bytes to an integer array of
5728     // same size and alignment.
5729     if (getTarget().isRenderScriptTarget()) {
5730       return coerceToIntArray(Ty, getContext(), getVMContext());
5731     }
5732     unsigned Alignment;
5733     if (Kind == AArch64ABIInfo::AAPCS) {
5734       Alignment = getContext().getTypeUnadjustedAlign(Ty);
5735       Alignment = Alignment < 128 ? 64 : 128;
5736     } else {
5737       Alignment = std::max(getContext().getTypeAlign(Ty),
5738                            (unsigned)getTarget().getPointerWidth(0));
5739     }
5740     Size = llvm::alignTo(Size, Alignment);
5741 
5742     // We use a pair of i64 for 16-byte aggregate with 8-byte alignment.
5743     // For aggregates with 16-byte alignment, we use i128.
5744     llvm::Type *BaseTy = llvm::Type::getIntNTy(getVMContext(), Alignment);
5745     return ABIArgInfo::getDirect(
5746         Size == Alignment ? BaseTy
5747                           : llvm::ArrayType::get(BaseTy, Size / Alignment));
5748   }
5749 
5750   return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
5751 }
5752 
classifyReturnType(QualType RetTy,bool IsVariadic) const5753 ABIArgInfo AArch64ABIInfo::classifyReturnType(QualType RetTy,
5754                                               bool IsVariadic) const {
5755   if (RetTy->isVoidType())
5756     return ABIArgInfo::getIgnore();
5757 
5758   if (const auto *VT = RetTy->getAs<VectorType>()) {
5759     if (VT->getVectorKind() == VectorType::SveFixedLengthDataVector ||
5760         VT->getVectorKind() == VectorType::SveFixedLengthPredicateVector)
5761       return coerceIllegalVector(RetTy);
5762   }
5763 
5764   // Large vector types should be returned via memory.
5765   if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 128)
5766     return getNaturalAlignIndirect(RetTy);
5767 
5768   if (!isAggregateTypeForABI(RetTy)) {
5769     // Treat an enum type as its underlying type.
5770     if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
5771       RetTy = EnumTy->getDecl()->getIntegerType();
5772 
5773     if (const auto *EIT = RetTy->getAs<ExtIntType>())
5774       if (EIT->getNumBits() > 128)
5775         return getNaturalAlignIndirect(RetTy);
5776 
5777     return (isPromotableIntegerTypeForABI(RetTy) && isDarwinPCS()
5778                 ? ABIArgInfo::getExtend(RetTy)
5779                 : ABIArgInfo::getDirect());
5780   }
5781 
5782   uint64_t Size = getContext().getTypeSize(RetTy);
5783   if (isEmptyRecord(getContext(), RetTy, true) || Size == 0)
5784     return ABIArgInfo::getIgnore();
5785 
5786   const Type *Base = nullptr;
5787   uint64_t Members = 0;
5788   if (isHomogeneousAggregate(RetTy, Base, Members) &&
5789       !(getTarget().getTriple().getArch() == llvm::Triple::aarch64_32 &&
5790         IsVariadic))
5791     // Homogeneous Floating-point Aggregates (HFAs) are returned directly.
5792     return ABIArgInfo::getDirect();
5793 
5794   // Aggregates <= 16 bytes are returned directly in registers or on the stack.
5795   if (Size <= 128) {
5796     // On RenderScript, coerce Aggregates <= 16 bytes to an integer array of
5797     // same size and alignment.
5798     if (getTarget().isRenderScriptTarget()) {
5799       return coerceToIntArray(RetTy, getContext(), getVMContext());
5800     }
5801 
5802     if (Size <= 64 && getDataLayout().isLittleEndian()) {
5803       // Composite types are returned in lower bits of a 64-bit register for LE,
5804       // and in higher bits for BE. However, integer types are always returned
5805       // in lower bits for both LE and BE, and they are not rounded up to
5806       // 64-bits. We can skip rounding up of composite types for LE, but not for
5807       // BE, otherwise composite types will be indistinguishable from integer
5808       // types.
5809       return ABIArgInfo::getDirect(
5810           llvm::IntegerType::get(getVMContext(), Size));
5811     }
5812 
5813     unsigned Alignment = getContext().getTypeAlign(RetTy);
5814     Size = llvm::alignTo(Size, 64); // round up to multiple of 8 bytes
5815 
5816     // We use a pair of i64 for 16-byte aggregate with 8-byte alignment.
5817     // For aggregates with 16-byte alignment, we use i128.
5818     if (Alignment < 128 && Size == 128) {
5819       llvm::Type *BaseTy = llvm::Type::getInt64Ty(getVMContext());
5820       return ABIArgInfo::getDirect(llvm::ArrayType::get(BaseTy, Size / 64));
5821     }
5822     return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), Size));
5823   }
5824 
5825   return getNaturalAlignIndirect(RetTy);
5826 }
5827 
5828 /// isIllegalVectorType - check whether the vector type is legal for AArch64.
isIllegalVectorType(QualType Ty) const5829 bool AArch64ABIInfo::isIllegalVectorType(QualType Ty) const {
5830   if (const VectorType *VT = Ty->getAs<VectorType>()) {
5831     // Check whether VT is a fixed-length SVE vector. These types are
5832     // represented as scalable vectors in function args/return and must be
5833     // coerced from fixed vectors.
5834     if (VT->getVectorKind() == VectorType::SveFixedLengthDataVector ||
5835         VT->getVectorKind() == VectorType::SveFixedLengthPredicateVector)
5836       return true;
5837 
5838     // Check whether VT is legal.
5839     unsigned NumElements = VT->getNumElements();
5840     uint64_t Size = getContext().getTypeSize(VT);
5841     // NumElements should be power of 2.
5842     if (!llvm::isPowerOf2_32(NumElements))
5843       return true;
5844 
5845     // arm64_32 has to be compatible with the ARM logic here, which allows huge
5846     // vectors for some reason.
5847     llvm::Triple Triple = getTarget().getTriple();
5848     if (Triple.getArch() == llvm::Triple::aarch64_32 &&
5849         Triple.isOSBinFormatMachO())
5850       return Size <= 32;
5851 
5852     return Size != 64 && (Size != 128 || NumElements == 1);
5853   }
5854   return false;
5855 }
5856 
isLegalVectorTypeForSwift(CharUnits totalSize,llvm::Type * eltTy,unsigned elts) const5857 bool AArch64ABIInfo::isLegalVectorTypeForSwift(CharUnits totalSize,
5858                                                llvm::Type *eltTy,
5859                                                unsigned elts) const {
5860   if (!llvm::isPowerOf2_32(elts))
5861     return false;
5862   if (totalSize.getQuantity() != 8 &&
5863       (totalSize.getQuantity() != 16 || elts == 1))
5864     return false;
5865   return true;
5866 }
5867 
isHomogeneousAggregateBaseType(QualType Ty) const5868 bool AArch64ABIInfo::isHomogeneousAggregateBaseType(QualType Ty) const {
5869   // Homogeneous aggregates for AAPCS64 must have base types of a floating
5870   // point type or a short-vector type. This is the same as the 32-bit ABI,
5871   // but with the difference that any floating-point type is allowed,
5872   // including __fp16.
5873   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
5874     if (BT->isFloatingPoint())
5875       return true;
5876   } else if (const VectorType *VT = Ty->getAs<VectorType>()) {
5877     unsigned VecSize = getContext().getTypeSize(VT);
5878     if (VecSize == 64 || VecSize == 128)
5879       return true;
5880   }
5881   return false;
5882 }
5883 
isHomogeneousAggregateSmallEnough(const Type * Base,uint64_t Members) const5884 bool AArch64ABIInfo::isHomogeneousAggregateSmallEnough(const Type *Base,
5885                                                        uint64_t Members) const {
5886   return Members <= 4;
5887 }
5888 
EmitAAPCSVAArg(Address VAListAddr,QualType Ty,CodeGenFunction & CGF) const5889 Address AArch64ABIInfo::EmitAAPCSVAArg(Address VAListAddr, QualType Ty,
5890                                        CodeGenFunction &CGF) const {
5891   ABIArgInfo AI = classifyArgumentType(Ty, /*IsVariadic=*/true,
5892                                        CGF.CurFnInfo->getCallingConvention());
5893   bool IsIndirect = AI.isIndirect();
5894 
5895   llvm::Type *BaseTy = CGF.ConvertType(Ty);
5896   if (IsIndirect)
5897     BaseTy = llvm::PointerType::getUnqual(BaseTy);
5898   else if (AI.getCoerceToType())
5899     BaseTy = AI.getCoerceToType();
5900 
5901   unsigned NumRegs = 1;
5902   if (llvm::ArrayType *ArrTy = dyn_cast<llvm::ArrayType>(BaseTy)) {
5903     BaseTy = ArrTy->getElementType();
5904     NumRegs = ArrTy->getNumElements();
5905   }
5906   bool IsFPR = BaseTy->isFloatingPointTy() || BaseTy->isVectorTy();
5907 
5908   // The AArch64 va_list type and handling is specified in the Procedure Call
5909   // Standard, section B.4:
5910   //
5911   // struct {
5912   //   void *__stack;
5913   //   void *__gr_top;
5914   //   void *__vr_top;
5915   //   int __gr_offs;
5916   //   int __vr_offs;
5917   // };
5918 
5919   llvm::BasicBlock *MaybeRegBlock = CGF.createBasicBlock("vaarg.maybe_reg");
5920   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
5921   llvm::BasicBlock *OnStackBlock = CGF.createBasicBlock("vaarg.on_stack");
5922   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
5923 
5924   CharUnits TySize = getContext().getTypeSizeInChars(Ty);
5925   CharUnits TyAlign = getContext().getTypeUnadjustedAlignInChars(Ty);
5926 
5927   Address reg_offs_p = Address::invalid();
5928   llvm::Value *reg_offs = nullptr;
5929   int reg_top_index;
5930   int RegSize = IsIndirect ? 8 : TySize.getQuantity();
5931   if (!IsFPR) {
5932     // 3 is the field number of __gr_offs
5933     reg_offs_p = CGF.Builder.CreateStructGEP(VAListAddr, 3, "gr_offs_p");
5934     reg_offs = CGF.Builder.CreateLoad(reg_offs_p, "gr_offs");
5935     reg_top_index = 1; // field number for __gr_top
5936     RegSize = llvm::alignTo(RegSize, 8);
5937   } else {
5938     // 4 is the field number of __vr_offs.
5939     reg_offs_p = CGF.Builder.CreateStructGEP(VAListAddr, 4, "vr_offs_p");
5940     reg_offs = CGF.Builder.CreateLoad(reg_offs_p, "vr_offs");
5941     reg_top_index = 2; // field number for __vr_top
5942     RegSize = 16 * NumRegs;
5943   }
5944 
5945   //=======================================
5946   // Find out where argument was passed
5947   //=======================================
5948 
5949   // If reg_offs >= 0 we're already using the stack for this type of
5950   // argument. We don't want to keep updating reg_offs (in case it overflows,
5951   // though anyone passing 2GB of arguments, each at most 16 bytes, deserves
5952   // whatever they get).
5953   llvm::Value *UsingStack = nullptr;
5954   UsingStack = CGF.Builder.CreateICmpSGE(
5955       reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, 0));
5956 
5957   CGF.Builder.CreateCondBr(UsingStack, OnStackBlock, MaybeRegBlock);
5958 
5959   // Otherwise, at least some kind of argument could go in these registers, the
5960   // question is whether this particular type is too big.
5961   CGF.EmitBlock(MaybeRegBlock);
5962 
5963   // Integer arguments may need to correct register alignment (for example a
5964   // "struct { __int128 a; };" gets passed in x_2N, x_{2N+1}). In this case we
5965   // align __gr_offs to calculate the potential address.
5966   if (!IsFPR && !IsIndirect && TyAlign.getQuantity() > 8) {
5967     int Align = TyAlign.getQuantity();
5968 
5969     reg_offs = CGF.Builder.CreateAdd(
5970         reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, Align - 1),
5971         "align_regoffs");
5972     reg_offs = CGF.Builder.CreateAnd(
5973         reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, -Align),
5974         "aligned_regoffs");
5975   }
5976 
5977   // Update the gr_offs/vr_offs pointer for next call to va_arg on this va_list.
5978   // The fact that this is done unconditionally reflects the fact that
5979   // allocating an argument to the stack also uses up all the remaining
5980   // registers of the appropriate kind.
5981   llvm::Value *NewOffset = nullptr;
5982   NewOffset = CGF.Builder.CreateAdd(
5983       reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, RegSize), "new_reg_offs");
5984   CGF.Builder.CreateStore(NewOffset, reg_offs_p);
5985 
5986   // Now we're in a position to decide whether this argument really was in
5987   // registers or not.
5988   llvm::Value *InRegs = nullptr;
5989   InRegs = CGF.Builder.CreateICmpSLE(
5990       NewOffset, llvm::ConstantInt::get(CGF.Int32Ty, 0), "inreg");
5991 
5992   CGF.Builder.CreateCondBr(InRegs, InRegBlock, OnStackBlock);
5993 
5994   //=======================================
5995   // Argument was in registers
5996   //=======================================
5997 
5998   // Now we emit the code for if the argument was originally passed in
5999   // registers. First start the appropriate block:
6000   CGF.EmitBlock(InRegBlock);
6001 
6002   llvm::Value *reg_top = nullptr;
6003   Address reg_top_p =
6004       CGF.Builder.CreateStructGEP(VAListAddr, reg_top_index, "reg_top_p");
6005   reg_top = CGF.Builder.CreateLoad(reg_top_p, "reg_top");
6006   Address BaseAddr(CGF.Builder.CreateInBoundsGEP(CGF.Int8Ty, reg_top, reg_offs),
6007                    CharUnits::fromQuantity(IsFPR ? 16 : 8));
6008   Address RegAddr = Address::invalid();
6009   llvm::Type *MemTy = CGF.ConvertTypeForMem(Ty);
6010 
6011   if (IsIndirect) {
6012     // If it's been passed indirectly (actually a struct), whatever we find from
6013     // stored registers or on the stack will actually be a struct **.
6014     MemTy = llvm::PointerType::getUnqual(MemTy);
6015   }
6016 
6017   const Type *Base = nullptr;
6018   uint64_t NumMembers = 0;
6019   bool IsHFA = isHomogeneousAggregate(Ty, Base, NumMembers);
6020   if (IsHFA && NumMembers > 1) {
6021     // Homogeneous aggregates passed in registers will have their elements split
6022     // and stored 16-bytes apart regardless of size (they're notionally in qN,
6023     // qN+1, ...). We reload and store into a temporary local variable
6024     // contiguously.
6025     assert(!IsIndirect && "Homogeneous aggregates should be passed directly");
6026     auto BaseTyInfo = getContext().getTypeInfoInChars(QualType(Base, 0));
6027     llvm::Type *BaseTy = CGF.ConvertType(QualType(Base, 0));
6028     llvm::Type *HFATy = llvm::ArrayType::get(BaseTy, NumMembers);
6029     Address Tmp = CGF.CreateTempAlloca(HFATy,
6030                                        std::max(TyAlign, BaseTyInfo.Align));
6031 
6032     // On big-endian platforms, the value will be right-aligned in its slot.
6033     int Offset = 0;
6034     if (CGF.CGM.getDataLayout().isBigEndian() &&
6035         BaseTyInfo.Width.getQuantity() < 16)
6036       Offset = 16 - BaseTyInfo.Width.getQuantity();
6037 
6038     for (unsigned i = 0; i < NumMembers; ++i) {
6039       CharUnits BaseOffset = CharUnits::fromQuantity(16 * i + Offset);
6040       Address LoadAddr =
6041         CGF.Builder.CreateConstInBoundsByteGEP(BaseAddr, BaseOffset);
6042       LoadAddr = CGF.Builder.CreateElementBitCast(LoadAddr, BaseTy);
6043 
6044       Address StoreAddr = CGF.Builder.CreateConstArrayGEP(Tmp, i);
6045 
6046       llvm::Value *Elem = CGF.Builder.CreateLoad(LoadAddr);
6047       CGF.Builder.CreateStore(Elem, StoreAddr);
6048     }
6049 
6050     RegAddr = CGF.Builder.CreateElementBitCast(Tmp, MemTy);
6051   } else {
6052     // Otherwise the object is contiguous in memory.
6053 
6054     // It might be right-aligned in its slot.
6055     CharUnits SlotSize = BaseAddr.getAlignment();
6056     if (CGF.CGM.getDataLayout().isBigEndian() && !IsIndirect &&
6057         (IsHFA || !isAggregateTypeForABI(Ty)) &&
6058         TySize < SlotSize) {
6059       CharUnits Offset = SlotSize - TySize;
6060       BaseAddr = CGF.Builder.CreateConstInBoundsByteGEP(BaseAddr, Offset);
6061     }
6062 
6063     RegAddr = CGF.Builder.CreateElementBitCast(BaseAddr, MemTy);
6064   }
6065 
6066   CGF.EmitBranch(ContBlock);
6067 
6068   //=======================================
6069   // Argument was on the stack
6070   //=======================================
6071   CGF.EmitBlock(OnStackBlock);
6072 
6073   Address stack_p = CGF.Builder.CreateStructGEP(VAListAddr, 0, "stack_p");
6074   llvm::Value *OnStackPtr = CGF.Builder.CreateLoad(stack_p, "stack");
6075 
6076   // Again, stack arguments may need realignment. In this case both integer and
6077   // floating-point ones might be affected.
6078   if (!IsIndirect && TyAlign.getQuantity() > 8) {
6079     int Align = TyAlign.getQuantity();
6080 
6081     OnStackPtr = CGF.Builder.CreatePtrToInt(OnStackPtr, CGF.Int64Ty);
6082 
6083     OnStackPtr = CGF.Builder.CreateAdd(
6084         OnStackPtr, llvm::ConstantInt::get(CGF.Int64Ty, Align - 1),
6085         "align_stack");
6086     OnStackPtr = CGF.Builder.CreateAnd(
6087         OnStackPtr, llvm::ConstantInt::get(CGF.Int64Ty, -Align),
6088         "align_stack");
6089 
6090     OnStackPtr = CGF.Builder.CreateIntToPtr(OnStackPtr, CGF.Int8PtrTy);
6091   }
6092   Address OnStackAddr(OnStackPtr,
6093                       std::max(CharUnits::fromQuantity(8), TyAlign));
6094 
6095   // All stack slots are multiples of 8 bytes.
6096   CharUnits StackSlotSize = CharUnits::fromQuantity(8);
6097   CharUnits StackSize;
6098   if (IsIndirect)
6099     StackSize = StackSlotSize;
6100   else
6101     StackSize = TySize.alignTo(StackSlotSize);
6102 
6103   llvm::Value *StackSizeC = CGF.Builder.getSize(StackSize);
6104   llvm::Value *NewStack = CGF.Builder.CreateInBoundsGEP(
6105       CGF.Int8Ty, OnStackPtr, StackSizeC, "new_stack");
6106 
6107   // Write the new value of __stack for the next call to va_arg
6108   CGF.Builder.CreateStore(NewStack, stack_p);
6109 
6110   if (CGF.CGM.getDataLayout().isBigEndian() && !isAggregateTypeForABI(Ty) &&
6111       TySize < StackSlotSize) {
6112     CharUnits Offset = StackSlotSize - TySize;
6113     OnStackAddr = CGF.Builder.CreateConstInBoundsByteGEP(OnStackAddr, Offset);
6114   }
6115 
6116   OnStackAddr = CGF.Builder.CreateElementBitCast(OnStackAddr, MemTy);
6117 
6118   CGF.EmitBranch(ContBlock);
6119 
6120   //=======================================
6121   // Tidy up
6122   //=======================================
6123   CGF.EmitBlock(ContBlock);
6124 
6125   Address ResAddr = emitMergePHI(CGF, RegAddr, InRegBlock,
6126                                  OnStackAddr, OnStackBlock, "vaargs.addr");
6127 
6128   if (IsIndirect)
6129     return Address(CGF.Builder.CreateLoad(ResAddr, "vaarg.addr"),
6130                    TyAlign);
6131 
6132   return ResAddr;
6133 }
6134 
EmitDarwinVAArg(Address VAListAddr,QualType Ty,CodeGenFunction & CGF) const6135 Address AArch64ABIInfo::EmitDarwinVAArg(Address VAListAddr, QualType Ty,
6136                                         CodeGenFunction &CGF) const {
6137   // The backend's lowering doesn't support va_arg for aggregates or
6138   // illegal vector types.  Lower VAArg here for these cases and use
6139   // the LLVM va_arg instruction for everything else.
6140   if (!isAggregateTypeForABI(Ty) && !isIllegalVectorType(Ty))
6141     return EmitVAArgInstr(CGF, VAListAddr, Ty, ABIArgInfo::getDirect());
6142 
6143   uint64_t PointerSize = getTarget().getPointerWidth(0) / 8;
6144   CharUnits SlotSize = CharUnits::fromQuantity(PointerSize);
6145 
6146   // Empty records are ignored for parameter passing purposes.
6147   if (isEmptyRecord(getContext(), Ty, true)) {
6148     Address Addr(CGF.Builder.CreateLoad(VAListAddr, "ap.cur"), SlotSize);
6149     Addr = CGF.Builder.CreateElementBitCast(Addr, CGF.ConvertTypeForMem(Ty));
6150     return Addr;
6151   }
6152 
6153   // The size of the actual thing passed, which might end up just
6154   // being a pointer for indirect types.
6155   auto TyInfo = getContext().getTypeInfoInChars(Ty);
6156 
6157   // Arguments bigger than 16 bytes which aren't homogeneous
6158   // aggregates should be passed indirectly.
6159   bool IsIndirect = false;
6160   if (TyInfo.Width.getQuantity() > 16) {
6161     const Type *Base = nullptr;
6162     uint64_t Members = 0;
6163     IsIndirect = !isHomogeneousAggregate(Ty, Base, Members);
6164   }
6165 
6166   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, IsIndirect,
6167                           TyInfo, SlotSize, /*AllowHigherAlign*/ true);
6168 }
6169 
EmitMSVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const6170 Address AArch64ABIInfo::EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
6171                                     QualType Ty) const {
6172   bool IsIndirect = false;
6173 
6174   // Composites larger than 16 bytes are passed by reference.
6175   if (isAggregateTypeForABI(Ty) && getContext().getTypeSize(Ty) > 128)
6176     IsIndirect = true;
6177 
6178   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, IsIndirect,
6179                           CGF.getContext().getTypeInfoInChars(Ty),
6180                           CharUnits::fromQuantity(8),
6181                           /*allowHigherAlign*/ false);
6182 }
6183 
6184 //===----------------------------------------------------------------------===//
6185 // ARM ABI Implementation
6186 //===----------------------------------------------------------------------===//
6187 
6188 namespace {
6189 
6190 class ARMABIInfo : public SwiftABIInfo {
6191 public:
6192   enum ABIKind {
6193     APCS = 0,
6194     AAPCS = 1,
6195     AAPCS_VFP = 2,
6196     AAPCS16_VFP = 3,
6197   };
6198 
6199 private:
6200   ABIKind Kind;
6201   bool IsFloatABISoftFP;
6202 
6203 public:
ARMABIInfo(CodeGenTypes & CGT,ABIKind _Kind)6204   ARMABIInfo(CodeGenTypes &CGT, ABIKind _Kind)
6205       : SwiftABIInfo(CGT), Kind(_Kind) {
6206     setCCs();
6207     IsFloatABISoftFP = CGT.getCodeGenOpts().FloatABI == "softfp" ||
6208         CGT.getCodeGenOpts().FloatABI == ""; // default
6209   }
6210 
isEABI() const6211   bool isEABI() const {
6212     switch (getTarget().getTriple().getEnvironment()) {
6213     case llvm::Triple::Android:
6214     case llvm::Triple::EABI:
6215     case llvm::Triple::EABIHF:
6216     case llvm::Triple::GNUEABI:
6217     case llvm::Triple::GNUEABIHF:
6218     case llvm::Triple::MuslEABI:
6219     case llvm::Triple::MuslEABIHF:
6220       return true;
6221     default:
6222       return false;
6223     }
6224   }
6225 
isEABIHF() const6226   bool isEABIHF() const {
6227     switch (getTarget().getTriple().getEnvironment()) {
6228     case llvm::Triple::EABIHF:
6229     case llvm::Triple::GNUEABIHF:
6230     case llvm::Triple::MuslEABIHF:
6231       return true;
6232     default:
6233       return false;
6234     }
6235   }
6236 
getABIKind() const6237   ABIKind getABIKind() const { return Kind; }
6238 
allowBFloatArgsAndRet() const6239   bool allowBFloatArgsAndRet() const override {
6240     return !IsFloatABISoftFP && getTarget().hasBFloat16Type();
6241   }
6242 
6243 private:
6244   ABIArgInfo classifyReturnType(QualType RetTy, bool isVariadic,
6245                                 unsigned functionCallConv) const;
6246   ABIArgInfo classifyArgumentType(QualType RetTy, bool isVariadic,
6247                                   unsigned functionCallConv) const;
6248   ABIArgInfo classifyHomogeneousAggregate(QualType Ty, const Type *Base,
6249                                           uint64_t Members) const;
6250   ABIArgInfo coerceIllegalVector(QualType Ty) const;
6251   bool isIllegalVectorType(QualType Ty) const;
6252   bool containsAnyFP16Vectors(QualType Ty) const;
6253 
6254   bool isHomogeneousAggregateBaseType(QualType Ty) const override;
6255   bool isHomogeneousAggregateSmallEnough(const Type *Ty,
6256                                          uint64_t Members) const override;
6257 
6258   bool isEffectivelyAAPCS_VFP(unsigned callConvention, bool acceptHalf) const;
6259 
6260   void computeInfo(CGFunctionInfo &FI) const override;
6261 
6262   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
6263                     QualType Ty) const override;
6264 
6265   llvm::CallingConv::ID getLLVMDefaultCC() const;
6266   llvm::CallingConv::ID getABIDefaultCC() const;
6267   void setCCs();
6268 
shouldPassIndirectlyForSwift(ArrayRef<llvm::Type * > scalars,bool asReturnValue) const6269   bool shouldPassIndirectlyForSwift(ArrayRef<llvm::Type*> scalars,
6270                                     bool asReturnValue) const override {
6271     return occupiesMoreThan(CGT, scalars, /*total*/ 4);
6272   }
isSwiftErrorInRegister() const6273   bool isSwiftErrorInRegister() const override {
6274     return true;
6275   }
6276   bool isLegalVectorTypeForSwift(CharUnits totalSize, llvm::Type *eltTy,
6277                                  unsigned elts) const override;
6278 };
6279 
6280 class ARMTargetCodeGenInfo : public TargetCodeGenInfo {
6281 public:
ARMTargetCodeGenInfo(CodeGenTypes & CGT,ARMABIInfo::ABIKind K)6282   ARMTargetCodeGenInfo(CodeGenTypes &CGT, ARMABIInfo::ABIKind K)
6283       : TargetCodeGenInfo(std::make_unique<ARMABIInfo>(CGT, K)) {}
6284 
getABIInfo() const6285   const ARMABIInfo &getABIInfo() const {
6286     return static_cast<const ARMABIInfo&>(TargetCodeGenInfo::getABIInfo());
6287   }
6288 
getDwarfEHStackPointer(CodeGen::CodeGenModule & M) const6289   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
6290     return 13;
6291   }
6292 
getARCRetainAutoreleasedReturnValueMarker() const6293   StringRef getARCRetainAutoreleasedReturnValueMarker() const override {
6294     return "mov\tr7, r7\t\t// marker for objc_retainAutoreleaseReturnValue";
6295   }
6296 
initDwarfEHRegSizeTable(CodeGen::CodeGenFunction & CGF,llvm::Value * Address) const6297   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
6298                                llvm::Value *Address) const override {
6299     llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
6300 
6301     // 0-15 are the 16 integer registers.
6302     AssignToArrayRange(CGF.Builder, Address, Four8, 0, 15);
6303     return false;
6304   }
6305 
getSizeOfUnwindException() const6306   unsigned getSizeOfUnwindException() const override {
6307     if (getABIInfo().isEABI()) return 88;
6308     return TargetCodeGenInfo::getSizeOfUnwindException();
6309   }
6310 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & CGM) const6311   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
6312                            CodeGen::CodeGenModule &CGM) const override {
6313     if (GV->isDeclaration())
6314       return;
6315     const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
6316     if (!FD)
6317       return;
6318 
6319     const ARMInterruptAttr *Attr = FD->getAttr<ARMInterruptAttr>();
6320     if (!Attr)
6321       return;
6322 
6323     const char *Kind;
6324     switch (Attr->getInterrupt()) {
6325     case ARMInterruptAttr::Generic: Kind = ""; break;
6326     case ARMInterruptAttr::IRQ:     Kind = "IRQ"; break;
6327     case ARMInterruptAttr::FIQ:     Kind = "FIQ"; break;
6328     case ARMInterruptAttr::SWI:     Kind = "SWI"; break;
6329     case ARMInterruptAttr::ABORT:   Kind = "ABORT"; break;
6330     case ARMInterruptAttr::UNDEF:   Kind = "UNDEF"; break;
6331     }
6332 
6333     llvm::Function *Fn = cast<llvm::Function>(GV);
6334 
6335     Fn->addFnAttr("interrupt", Kind);
6336 
6337     ARMABIInfo::ABIKind ABI = cast<ARMABIInfo>(getABIInfo()).getABIKind();
6338     if (ABI == ARMABIInfo::APCS)
6339       return;
6340 
6341     // AAPCS guarantees that sp will be 8-byte aligned on any public interface,
6342     // however this is not necessarily true on taking any interrupt. Instruct
6343     // the backend to perform a realignment as part of the function prologue.
6344     llvm::AttrBuilder B;
6345     B.addStackAlignmentAttr(8);
6346     Fn->addAttributes(llvm::AttributeList::FunctionIndex, B);
6347   }
6348 };
6349 
6350 class WindowsARMTargetCodeGenInfo : public ARMTargetCodeGenInfo {
6351 public:
WindowsARMTargetCodeGenInfo(CodeGenTypes & CGT,ARMABIInfo::ABIKind K)6352   WindowsARMTargetCodeGenInfo(CodeGenTypes &CGT, ARMABIInfo::ABIKind K)
6353       : ARMTargetCodeGenInfo(CGT, K) {}
6354 
6355   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
6356                            CodeGen::CodeGenModule &CGM) const override;
6357 
getDependentLibraryOption(llvm::StringRef Lib,llvm::SmallString<24> & Opt) const6358   void getDependentLibraryOption(llvm::StringRef Lib,
6359                                  llvm::SmallString<24> &Opt) const override {
6360     Opt = "/DEFAULTLIB:" + qualifyWindowsLibrary(Lib);
6361   }
6362 
getDetectMismatchOption(llvm::StringRef Name,llvm::StringRef Value,llvm::SmallString<32> & Opt) const6363   void getDetectMismatchOption(llvm::StringRef Name, llvm::StringRef Value,
6364                                llvm::SmallString<32> &Opt) const override {
6365     Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
6366   }
6367 };
6368 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & CGM) const6369 void WindowsARMTargetCodeGenInfo::setTargetAttributes(
6370     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &CGM) const {
6371   ARMTargetCodeGenInfo::setTargetAttributes(D, GV, CGM);
6372   if (GV->isDeclaration())
6373     return;
6374   addStackProbeTargetAttributes(D, GV, CGM);
6375 }
6376 }
6377 
computeInfo(CGFunctionInfo & FI) const6378 void ARMABIInfo::computeInfo(CGFunctionInfo &FI) const {
6379   if (!::classifyReturnType(getCXXABI(), FI, *this))
6380     FI.getReturnInfo() = classifyReturnType(FI.getReturnType(), FI.isVariadic(),
6381                                             FI.getCallingConvention());
6382 
6383   for (auto &I : FI.arguments())
6384     I.info = classifyArgumentType(I.type, FI.isVariadic(),
6385                                   FI.getCallingConvention());
6386 
6387 
6388   // Always honor user-specified calling convention.
6389   if (FI.getCallingConvention() != llvm::CallingConv::C)
6390     return;
6391 
6392   llvm::CallingConv::ID cc = getRuntimeCC();
6393   if (cc != llvm::CallingConv::C)
6394     FI.setEffectiveCallingConvention(cc);
6395 }
6396 
6397 /// Return the default calling convention that LLVM will use.
getLLVMDefaultCC() const6398 llvm::CallingConv::ID ARMABIInfo::getLLVMDefaultCC() const {
6399   // The default calling convention that LLVM will infer.
6400   if (isEABIHF() || getTarget().getTriple().isWatchABI())
6401     return llvm::CallingConv::ARM_AAPCS_VFP;
6402   else if (isEABI())
6403     return llvm::CallingConv::ARM_AAPCS;
6404   else
6405     return llvm::CallingConv::ARM_APCS;
6406 }
6407 
6408 /// Return the calling convention that our ABI would like us to use
6409 /// as the C calling convention.
getABIDefaultCC() const6410 llvm::CallingConv::ID ARMABIInfo::getABIDefaultCC() const {
6411   switch (getABIKind()) {
6412   case APCS: return llvm::CallingConv::ARM_APCS;
6413   case AAPCS: return llvm::CallingConv::ARM_AAPCS;
6414   case AAPCS_VFP: return llvm::CallingConv::ARM_AAPCS_VFP;
6415   case AAPCS16_VFP: return llvm::CallingConv::ARM_AAPCS_VFP;
6416   }
6417   llvm_unreachable("bad ABI kind");
6418 }
6419 
setCCs()6420 void ARMABIInfo::setCCs() {
6421   assert(getRuntimeCC() == llvm::CallingConv::C);
6422 
6423   // Don't muddy up the IR with a ton of explicit annotations if
6424   // they'd just match what LLVM will infer from the triple.
6425   llvm::CallingConv::ID abiCC = getABIDefaultCC();
6426   if (abiCC != getLLVMDefaultCC())
6427     RuntimeCC = abiCC;
6428 }
6429 
coerceIllegalVector(QualType Ty) const6430 ABIArgInfo ARMABIInfo::coerceIllegalVector(QualType Ty) const {
6431   uint64_t Size = getContext().getTypeSize(Ty);
6432   if (Size <= 32) {
6433     llvm::Type *ResType =
6434         llvm::Type::getInt32Ty(getVMContext());
6435     return ABIArgInfo::getDirect(ResType);
6436   }
6437   if (Size == 64 || Size == 128) {
6438     auto *ResType = llvm::FixedVectorType::get(
6439         llvm::Type::getInt32Ty(getVMContext()), Size / 32);
6440     return ABIArgInfo::getDirect(ResType);
6441   }
6442   return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
6443 }
6444 
classifyHomogeneousAggregate(QualType Ty,const Type * Base,uint64_t Members) const6445 ABIArgInfo ARMABIInfo::classifyHomogeneousAggregate(QualType Ty,
6446                                                     const Type *Base,
6447                                                     uint64_t Members) const {
6448   assert(Base && "Base class should be set for homogeneous aggregate");
6449   // Base can be a floating-point or a vector.
6450   if (const VectorType *VT = Base->getAs<VectorType>()) {
6451     // FP16 vectors should be converted to integer vectors
6452     if (!getTarget().hasLegalHalfType() && containsAnyFP16Vectors(Ty)) {
6453       uint64_t Size = getContext().getTypeSize(VT);
6454       auto *NewVecTy = llvm::FixedVectorType::get(
6455           llvm::Type::getInt32Ty(getVMContext()), Size / 32);
6456       llvm::Type *Ty = llvm::ArrayType::get(NewVecTy, Members);
6457       return ABIArgInfo::getDirect(Ty, 0, nullptr, false);
6458     }
6459   }
6460   unsigned Align = 0;
6461   if (getABIKind() == ARMABIInfo::AAPCS ||
6462       getABIKind() == ARMABIInfo::AAPCS_VFP) {
6463     // For alignment adjusted HFAs, cap the argument alignment to 8, leave it
6464     // default otherwise.
6465     Align = getContext().getTypeUnadjustedAlignInChars(Ty).getQuantity();
6466     unsigned BaseAlign = getContext().getTypeAlignInChars(Base).getQuantity();
6467     Align = (Align > BaseAlign && Align >= 8) ? 8 : 0;
6468   }
6469   return ABIArgInfo::getDirect(nullptr, 0, nullptr, false, Align);
6470 }
6471 
classifyArgumentType(QualType Ty,bool isVariadic,unsigned functionCallConv) const6472 ABIArgInfo ARMABIInfo::classifyArgumentType(QualType Ty, bool isVariadic,
6473                                             unsigned functionCallConv) const {
6474   // 6.1.2.1 The following argument types are VFP CPRCs:
6475   //   A single-precision floating-point type (including promoted
6476   //   half-precision types); A double-precision floating-point type;
6477   //   A 64-bit or 128-bit containerized vector type; Homogeneous Aggregate
6478   //   with a Base Type of a single- or double-precision floating-point type,
6479   //   64-bit containerized vectors or 128-bit containerized vectors with one
6480   //   to four Elements.
6481   // Variadic functions should always marshal to the base standard.
6482   bool IsAAPCS_VFP =
6483       !isVariadic && isEffectivelyAAPCS_VFP(functionCallConv, /* AAPCS16 */ false);
6484 
6485   Ty = useFirstFieldIfTransparentUnion(Ty);
6486 
6487   // Handle illegal vector types here.
6488   if (isIllegalVectorType(Ty))
6489     return coerceIllegalVector(Ty);
6490 
6491   if (!isAggregateTypeForABI(Ty)) {
6492     // Treat an enum type as its underlying type.
6493     if (const EnumType *EnumTy = Ty->getAs<EnumType>()) {
6494       Ty = EnumTy->getDecl()->getIntegerType();
6495     }
6496 
6497     if (const auto *EIT = Ty->getAs<ExtIntType>())
6498       if (EIT->getNumBits() > 64)
6499         return getNaturalAlignIndirect(Ty, /*ByVal=*/true);
6500 
6501     return (isPromotableIntegerTypeForABI(Ty) ? ABIArgInfo::getExtend(Ty)
6502                                               : ABIArgInfo::getDirect());
6503   }
6504 
6505   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
6506     return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
6507   }
6508 
6509   // Ignore empty records.
6510   if (isEmptyRecord(getContext(), Ty, true))
6511     return ABIArgInfo::getIgnore();
6512 
6513   if (IsAAPCS_VFP) {
6514     // Homogeneous Aggregates need to be expanded when we can fit the aggregate
6515     // into VFP registers.
6516     const Type *Base = nullptr;
6517     uint64_t Members = 0;
6518     if (isHomogeneousAggregate(Ty, Base, Members))
6519       return classifyHomogeneousAggregate(Ty, Base, Members);
6520   } else if (getABIKind() == ARMABIInfo::AAPCS16_VFP) {
6521     // WatchOS does have homogeneous aggregates. Note that we intentionally use
6522     // this convention even for a variadic function: the backend will use GPRs
6523     // if needed.
6524     const Type *Base = nullptr;
6525     uint64_t Members = 0;
6526     if (isHomogeneousAggregate(Ty, Base, Members)) {
6527       assert(Base && Members <= 4 && "unexpected homogeneous aggregate");
6528       llvm::Type *Ty =
6529         llvm::ArrayType::get(CGT.ConvertType(QualType(Base, 0)), Members);
6530       return ABIArgInfo::getDirect(Ty, 0, nullptr, false);
6531     }
6532   }
6533 
6534   if (getABIKind() == ARMABIInfo::AAPCS16_VFP &&
6535       getContext().getTypeSizeInChars(Ty) > CharUnits::fromQuantity(16)) {
6536     // WatchOS is adopting the 64-bit AAPCS rule on composite types: if they're
6537     // bigger than 128-bits, they get placed in space allocated by the caller,
6538     // and a pointer is passed.
6539     return ABIArgInfo::getIndirect(
6540         CharUnits::fromQuantity(getContext().getTypeAlign(Ty) / 8), false);
6541   }
6542 
6543   // Support byval for ARM.
6544   // The ABI alignment for APCS is 4-byte and for AAPCS at least 4-byte and at
6545   // most 8-byte. We realign the indirect argument if type alignment is bigger
6546   // than ABI alignment.
6547   uint64_t ABIAlign = 4;
6548   uint64_t TyAlign;
6549   if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
6550       getABIKind() == ARMABIInfo::AAPCS) {
6551     TyAlign = getContext().getTypeUnadjustedAlignInChars(Ty).getQuantity();
6552     ABIAlign = std::min(std::max(TyAlign, (uint64_t)4), (uint64_t)8);
6553   } else {
6554     TyAlign = getContext().getTypeAlignInChars(Ty).getQuantity();
6555   }
6556   if (getContext().getTypeSizeInChars(Ty) > CharUnits::fromQuantity(64)) {
6557     assert(getABIKind() != ARMABIInfo::AAPCS16_VFP && "unexpected byval");
6558     return ABIArgInfo::getIndirect(CharUnits::fromQuantity(ABIAlign),
6559                                    /*ByVal=*/true,
6560                                    /*Realign=*/TyAlign > ABIAlign);
6561   }
6562 
6563   // On RenderScript, coerce Aggregates <= 64 bytes to an integer array of
6564   // same size and alignment.
6565   if (getTarget().isRenderScriptTarget()) {
6566     return coerceToIntArray(Ty, getContext(), getVMContext());
6567   }
6568 
6569   // Otherwise, pass by coercing to a structure of the appropriate size.
6570   llvm::Type* ElemTy;
6571   unsigned SizeRegs;
6572   // FIXME: Try to match the types of the arguments more accurately where
6573   // we can.
6574   if (TyAlign <= 4) {
6575     ElemTy = llvm::Type::getInt32Ty(getVMContext());
6576     SizeRegs = (getContext().getTypeSize(Ty) + 31) / 32;
6577   } else {
6578     ElemTy = llvm::Type::getInt64Ty(getVMContext());
6579     SizeRegs = (getContext().getTypeSize(Ty) + 63) / 64;
6580   }
6581 
6582   return ABIArgInfo::getDirect(llvm::ArrayType::get(ElemTy, SizeRegs));
6583 }
6584 
isIntegerLikeType(QualType Ty,ASTContext & Context,llvm::LLVMContext & VMContext)6585 static bool isIntegerLikeType(QualType Ty, ASTContext &Context,
6586                               llvm::LLVMContext &VMContext) {
6587   // APCS, C Language Calling Conventions, Non-Simple Return Values: A structure
6588   // is called integer-like if its size is less than or equal to one word, and
6589   // the offset of each of its addressable sub-fields is zero.
6590 
6591   uint64_t Size = Context.getTypeSize(Ty);
6592 
6593   // Check that the type fits in a word.
6594   if (Size > 32)
6595     return false;
6596 
6597   // FIXME: Handle vector types!
6598   if (Ty->isVectorType())
6599     return false;
6600 
6601   // Float types are never treated as "integer like".
6602   if (Ty->isRealFloatingType())
6603     return false;
6604 
6605   // If this is a builtin or pointer type then it is ok.
6606   if (Ty->getAs<BuiltinType>() || Ty->isPointerType())
6607     return true;
6608 
6609   // Small complex integer types are "integer like".
6610   if (const ComplexType *CT = Ty->getAs<ComplexType>())
6611     return isIntegerLikeType(CT->getElementType(), Context, VMContext);
6612 
6613   // Single element and zero sized arrays should be allowed, by the definition
6614   // above, but they are not.
6615 
6616   // Otherwise, it must be a record type.
6617   const RecordType *RT = Ty->getAs<RecordType>();
6618   if (!RT) return false;
6619 
6620   // Ignore records with flexible arrays.
6621   const RecordDecl *RD = RT->getDecl();
6622   if (RD->hasFlexibleArrayMember())
6623     return false;
6624 
6625   // Check that all sub-fields are at offset 0, and are themselves "integer
6626   // like".
6627   const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
6628 
6629   bool HadField = false;
6630   unsigned idx = 0;
6631   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
6632        i != e; ++i, ++idx) {
6633     const FieldDecl *FD = *i;
6634 
6635     // Bit-fields are not addressable, we only need to verify they are "integer
6636     // like". We still have to disallow a subsequent non-bitfield, for example:
6637     //   struct { int : 0; int x }
6638     // is non-integer like according to gcc.
6639     if (FD->isBitField()) {
6640       if (!RD->isUnion())
6641         HadField = true;
6642 
6643       if (!isIntegerLikeType(FD->getType(), Context, VMContext))
6644         return false;
6645 
6646       continue;
6647     }
6648 
6649     // Check if this field is at offset 0.
6650     if (Layout.getFieldOffset(idx) != 0)
6651       return false;
6652 
6653     if (!isIntegerLikeType(FD->getType(), Context, VMContext))
6654       return false;
6655 
6656     // Only allow at most one field in a structure. This doesn't match the
6657     // wording above, but follows gcc in situations with a field following an
6658     // empty structure.
6659     if (!RD->isUnion()) {
6660       if (HadField)
6661         return false;
6662 
6663       HadField = true;
6664     }
6665   }
6666 
6667   return true;
6668 }
6669 
classifyReturnType(QualType RetTy,bool isVariadic,unsigned functionCallConv) const6670 ABIArgInfo ARMABIInfo::classifyReturnType(QualType RetTy, bool isVariadic,
6671                                           unsigned functionCallConv) const {
6672 
6673   // Variadic functions should always marshal to the base standard.
6674   bool IsAAPCS_VFP =
6675       !isVariadic && isEffectivelyAAPCS_VFP(functionCallConv, /* AAPCS16 */ true);
6676 
6677   if (RetTy->isVoidType())
6678     return ABIArgInfo::getIgnore();
6679 
6680   if (const VectorType *VT = RetTy->getAs<VectorType>()) {
6681     // Large vector types should be returned via memory.
6682     if (getContext().getTypeSize(RetTy) > 128)
6683       return getNaturalAlignIndirect(RetTy);
6684     // TODO: FP16/BF16 vectors should be converted to integer vectors
6685     // This check is similar  to isIllegalVectorType - refactor?
6686     if ((!getTarget().hasLegalHalfType() &&
6687         (VT->getElementType()->isFloat16Type() ||
6688          VT->getElementType()->isHalfType())) ||
6689         (IsFloatABISoftFP &&
6690          VT->getElementType()->isBFloat16Type()))
6691       return coerceIllegalVector(RetTy);
6692   }
6693 
6694   if (!isAggregateTypeForABI(RetTy)) {
6695     // Treat an enum type as its underlying type.
6696     if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
6697       RetTy = EnumTy->getDecl()->getIntegerType();
6698 
6699     if (const auto *EIT = RetTy->getAs<ExtIntType>())
6700       if (EIT->getNumBits() > 64)
6701         return getNaturalAlignIndirect(RetTy, /*ByVal=*/false);
6702 
6703     return isPromotableIntegerTypeForABI(RetTy) ? ABIArgInfo::getExtend(RetTy)
6704                                                 : ABIArgInfo::getDirect();
6705   }
6706 
6707   // Are we following APCS?
6708   if (getABIKind() == APCS) {
6709     if (isEmptyRecord(getContext(), RetTy, false))
6710       return ABIArgInfo::getIgnore();
6711 
6712     // Complex types are all returned as packed integers.
6713     //
6714     // FIXME: Consider using 2 x vector types if the back end handles them
6715     // correctly.
6716     if (RetTy->isAnyComplexType())
6717       return ABIArgInfo::getDirect(llvm::IntegerType::get(
6718           getVMContext(), getContext().getTypeSize(RetTy)));
6719 
6720     // Integer like structures are returned in r0.
6721     if (isIntegerLikeType(RetTy, getContext(), getVMContext())) {
6722       // Return in the smallest viable integer type.
6723       uint64_t Size = getContext().getTypeSize(RetTy);
6724       if (Size <= 8)
6725         return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
6726       if (Size <= 16)
6727         return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
6728       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
6729     }
6730 
6731     // Otherwise return in memory.
6732     return getNaturalAlignIndirect(RetTy);
6733   }
6734 
6735   // Otherwise this is an AAPCS variant.
6736 
6737   if (isEmptyRecord(getContext(), RetTy, true))
6738     return ABIArgInfo::getIgnore();
6739 
6740   // Check for homogeneous aggregates with AAPCS-VFP.
6741   if (IsAAPCS_VFP) {
6742     const Type *Base = nullptr;
6743     uint64_t Members = 0;
6744     if (isHomogeneousAggregate(RetTy, Base, Members))
6745       return classifyHomogeneousAggregate(RetTy, Base, Members);
6746   }
6747 
6748   // Aggregates <= 4 bytes are returned in r0; other aggregates
6749   // are returned indirectly.
6750   uint64_t Size = getContext().getTypeSize(RetTy);
6751   if (Size <= 32) {
6752     // On RenderScript, coerce Aggregates <= 4 bytes to an integer array of
6753     // same size and alignment.
6754     if (getTarget().isRenderScriptTarget()) {
6755       return coerceToIntArray(RetTy, getContext(), getVMContext());
6756     }
6757     if (getDataLayout().isBigEndian())
6758       // Return in 32 bit integer integer type (as if loaded by LDR, AAPCS 5.4)
6759       return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
6760 
6761     // Return in the smallest viable integer type.
6762     if (Size <= 8)
6763       return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
6764     if (Size <= 16)
6765       return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
6766     return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
6767   } else if (Size <= 128 && getABIKind() == AAPCS16_VFP) {
6768     llvm::Type *Int32Ty = llvm::Type::getInt32Ty(getVMContext());
6769     llvm::Type *CoerceTy =
6770         llvm::ArrayType::get(Int32Ty, llvm::alignTo(Size, 32) / 32);
6771     return ABIArgInfo::getDirect(CoerceTy);
6772   }
6773 
6774   return getNaturalAlignIndirect(RetTy);
6775 }
6776 
6777 /// isIllegalVector - check whether Ty is an illegal vector type.
isIllegalVectorType(QualType Ty) const6778 bool ARMABIInfo::isIllegalVectorType(QualType Ty) const {
6779   if (const VectorType *VT = Ty->getAs<VectorType> ()) {
6780     // On targets that don't support half, fp16 or bfloat, they are expanded
6781     // into float, and we don't want the ABI to depend on whether or not they
6782     // are supported in hardware. Thus return false to coerce vectors of these
6783     // types into integer vectors.
6784     // We do not depend on hasLegalHalfType for bfloat as it is a
6785     // separate IR type.
6786     if ((!getTarget().hasLegalHalfType() &&
6787         (VT->getElementType()->isFloat16Type() ||
6788          VT->getElementType()->isHalfType())) ||
6789         (IsFloatABISoftFP &&
6790          VT->getElementType()->isBFloat16Type()))
6791       return true;
6792     if (isAndroid()) {
6793       // Android shipped using Clang 3.1, which supported a slightly different
6794       // vector ABI. The primary differences were that 3-element vector types
6795       // were legal, and so were sub 32-bit vectors (i.e. <2 x i8>). This path
6796       // accepts that legacy behavior for Android only.
6797       // Check whether VT is legal.
6798       unsigned NumElements = VT->getNumElements();
6799       // NumElements should be power of 2 or equal to 3.
6800       if (!llvm::isPowerOf2_32(NumElements) && NumElements != 3)
6801         return true;
6802     } else {
6803       // Check whether VT is legal.
6804       unsigned NumElements = VT->getNumElements();
6805       uint64_t Size = getContext().getTypeSize(VT);
6806       // NumElements should be power of 2.
6807       if (!llvm::isPowerOf2_32(NumElements))
6808         return true;
6809       // Size should be greater than 32 bits.
6810       return Size <= 32;
6811     }
6812   }
6813   return false;
6814 }
6815 
6816 /// Return true if a type contains any 16-bit floating point vectors
containsAnyFP16Vectors(QualType Ty) const6817 bool ARMABIInfo::containsAnyFP16Vectors(QualType Ty) const {
6818   if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) {
6819     uint64_t NElements = AT->getSize().getZExtValue();
6820     if (NElements == 0)
6821       return false;
6822     return containsAnyFP16Vectors(AT->getElementType());
6823   } else if (const RecordType *RT = Ty->getAs<RecordType>()) {
6824     const RecordDecl *RD = RT->getDecl();
6825 
6826     // If this is a C++ record, check the bases first.
6827     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
6828       if (llvm::any_of(CXXRD->bases(), [this](const CXXBaseSpecifier &B) {
6829             return containsAnyFP16Vectors(B.getType());
6830           }))
6831         return true;
6832 
6833     if (llvm::any_of(RD->fields(), [this](FieldDecl *FD) {
6834           return FD && containsAnyFP16Vectors(FD->getType());
6835         }))
6836       return true;
6837 
6838     return false;
6839   } else {
6840     if (const VectorType *VT = Ty->getAs<VectorType>())
6841       return (VT->getElementType()->isFloat16Type() ||
6842               VT->getElementType()->isBFloat16Type() ||
6843               VT->getElementType()->isHalfType());
6844     return false;
6845   }
6846 }
6847 
isLegalVectorTypeForSwift(CharUnits vectorSize,llvm::Type * eltTy,unsigned numElts) const6848 bool ARMABIInfo::isLegalVectorTypeForSwift(CharUnits vectorSize,
6849                                            llvm::Type *eltTy,
6850                                            unsigned numElts) const {
6851   if (!llvm::isPowerOf2_32(numElts))
6852     return false;
6853   unsigned size = getDataLayout().getTypeStoreSizeInBits(eltTy);
6854   if (size > 64)
6855     return false;
6856   if (vectorSize.getQuantity() != 8 &&
6857       (vectorSize.getQuantity() != 16 || numElts == 1))
6858     return false;
6859   return true;
6860 }
6861 
isHomogeneousAggregateBaseType(QualType Ty) const6862 bool ARMABIInfo::isHomogeneousAggregateBaseType(QualType Ty) const {
6863   // Homogeneous aggregates for AAPCS-VFP must have base types of float,
6864   // double, or 64-bit or 128-bit vectors.
6865   if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
6866     if (BT->getKind() == BuiltinType::Float ||
6867         BT->getKind() == BuiltinType::Double ||
6868         BT->getKind() == BuiltinType::LongDouble)
6869       return true;
6870   } else if (const VectorType *VT = Ty->getAs<VectorType>()) {
6871     unsigned VecSize = getContext().getTypeSize(VT);
6872     if (VecSize == 64 || VecSize == 128)
6873       return true;
6874   }
6875   return false;
6876 }
6877 
isHomogeneousAggregateSmallEnough(const Type * Base,uint64_t Members) const6878 bool ARMABIInfo::isHomogeneousAggregateSmallEnough(const Type *Base,
6879                                                    uint64_t Members) const {
6880   return Members <= 4;
6881 }
6882 
isEffectivelyAAPCS_VFP(unsigned callConvention,bool acceptHalf) const6883 bool ARMABIInfo::isEffectivelyAAPCS_VFP(unsigned callConvention,
6884                                         bool acceptHalf) const {
6885   // Give precedence to user-specified calling conventions.
6886   if (callConvention != llvm::CallingConv::C)
6887     return (callConvention == llvm::CallingConv::ARM_AAPCS_VFP);
6888   else
6889     return (getABIKind() == AAPCS_VFP) ||
6890            (acceptHalf && (getABIKind() == AAPCS16_VFP));
6891 }
6892 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const6893 Address ARMABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
6894                               QualType Ty) const {
6895   CharUnits SlotSize = CharUnits::fromQuantity(4);
6896 
6897   // Empty records are ignored for parameter passing purposes.
6898   if (isEmptyRecord(getContext(), Ty, true)) {
6899     Address Addr(CGF.Builder.CreateLoad(VAListAddr), SlotSize);
6900     Addr = CGF.Builder.CreateElementBitCast(Addr, CGF.ConvertTypeForMem(Ty));
6901     return Addr;
6902   }
6903 
6904   CharUnits TySize = getContext().getTypeSizeInChars(Ty);
6905   CharUnits TyAlignForABI = getContext().getTypeUnadjustedAlignInChars(Ty);
6906 
6907   // Use indirect if size of the illegal vector is bigger than 16 bytes.
6908   bool IsIndirect = false;
6909   const Type *Base = nullptr;
6910   uint64_t Members = 0;
6911   if (TySize > CharUnits::fromQuantity(16) && isIllegalVectorType(Ty)) {
6912     IsIndirect = true;
6913 
6914   // ARMv7k passes structs bigger than 16 bytes indirectly, in space
6915   // allocated by the caller.
6916   } else if (TySize > CharUnits::fromQuantity(16) &&
6917              getABIKind() == ARMABIInfo::AAPCS16_VFP &&
6918              !isHomogeneousAggregate(Ty, Base, Members)) {
6919     IsIndirect = true;
6920 
6921   // Otherwise, bound the type's ABI alignment.
6922   // The ABI alignment for 64-bit or 128-bit vectors is 8 for AAPCS and 4 for
6923   // APCS. For AAPCS, the ABI alignment is at least 4-byte and at most 8-byte.
6924   // Our callers should be prepared to handle an under-aligned address.
6925   } else if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
6926              getABIKind() == ARMABIInfo::AAPCS) {
6927     TyAlignForABI = std::max(TyAlignForABI, CharUnits::fromQuantity(4));
6928     TyAlignForABI = std::min(TyAlignForABI, CharUnits::fromQuantity(8));
6929   } else if (getABIKind() == ARMABIInfo::AAPCS16_VFP) {
6930     // ARMv7k allows type alignment up to 16 bytes.
6931     TyAlignForABI = std::max(TyAlignForABI, CharUnits::fromQuantity(4));
6932     TyAlignForABI = std::min(TyAlignForABI, CharUnits::fromQuantity(16));
6933   } else {
6934     TyAlignForABI = CharUnits::fromQuantity(4);
6935   }
6936 
6937   TypeInfoChars TyInfo(TySize, TyAlignForABI, false);
6938   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, IsIndirect, TyInfo,
6939                           SlotSize, /*AllowHigherAlign*/ true);
6940 }
6941 
6942 //===----------------------------------------------------------------------===//
6943 // NVPTX ABI Implementation
6944 //===----------------------------------------------------------------------===//
6945 
6946 namespace {
6947 
6948 class NVPTXTargetCodeGenInfo;
6949 
6950 class NVPTXABIInfo : public ABIInfo {
6951   NVPTXTargetCodeGenInfo &CGInfo;
6952 
6953 public:
NVPTXABIInfo(CodeGenTypes & CGT,NVPTXTargetCodeGenInfo & Info)6954   NVPTXABIInfo(CodeGenTypes &CGT, NVPTXTargetCodeGenInfo &Info)
6955       : ABIInfo(CGT), CGInfo(Info) {}
6956 
6957   ABIArgInfo classifyReturnType(QualType RetTy) const;
6958   ABIArgInfo classifyArgumentType(QualType Ty) const;
6959 
6960   void computeInfo(CGFunctionInfo &FI) const override;
6961   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
6962                     QualType Ty) const override;
6963   bool isUnsupportedType(QualType T) const;
6964   ABIArgInfo coerceToIntArrayWithLimit(QualType Ty, unsigned MaxSize) const;
6965 };
6966 
6967 class NVPTXTargetCodeGenInfo : public TargetCodeGenInfo {
6968 public:
NVPTXTargetCodeGenInfo(CodeGenTypes & CGT)6969   NVPTXTargetCodeGenInfo(CodeGenTypes &CGT)
6970       : TargetCodeGenInfo(std::make_unique<NVPTXABIInfo>(CGT, *this)) {}
6971 
6972   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
6973                            CodeGen::CodeGenModule &M) const override;
6974   bool shouldEmitStaticExternCAliases() const override;
6975 
getCUDADeviceBuiltinSurfaceDeviceType() const6976   llvm::Type *getCUDADeviceBuiltinSurfaceDeviceType() const override {
6977     // On the device side, surface reference is represented as an object handle
6978     // in 64-bit integer.
6979     return llvm::Type::getInt64Ty(getABIInfo().getVMContext());
6980   }
6981 
getCUDADeviceBuiltinTextureDeviceType() const6982   llvm::Type *getCUDADeviceBuiltinTextureDeviceType() const override {
6983     // On the device side, texture reference is represented as an object handle
6984     // in 64-bit integer.
6985     return llvm::Type::getInt64Ty(getABIInfo().getVMContext());
6986   }
6987 
emitCUDADeviceBuiltinSurfaceDeviceCopy(CodeGenFunction & CGF,LValue Dst,LValue Src) const6988   bool emitCUDADeviceBuiltinSurfaceDeviceCopy(CodeGenFunction &CGF, LValue Dst,
6989                                               LValue Src) const override {
6990     emitBuiltinSurfTexDeviceCopy(CGF, Dst, Src);
6991     return true;
6992   }
6993 
emitCUDADeviceBuiltinTextureDeviceCopy(CodeGenFunction & CGF,LValue Dst,LValue Src) const6994   bool emitCUDADeviceBuiltinTextureDeviceCopy(CodeGenFunction &CGF, LValue Dst,
6995                                               LValue Src) const override {
6996     emitBuiltinSurfTexDeviceCopy(CGF, Dst, Src);
6997     return true;
6998   }
6999 
7000 private:
7001   // Adds a NamedMDNode with GV, Name, and Operand as operands, and adds the
7002   // resulting MDNode to the nvvm.annotations MDNode.
7003   static void addNVVMMetadata(llvm::GlobalValue *GV, StringRef Name,
7004                               int Operand);
7005 
emitBuiltinSurfTexDeviceCopy(CodeGenFunction & CGF,LValue Dst,LValue Src)7006   static void emitBuiltinSurfTexDeviceCopy(CodeGenFunction &CGF, LValue Dst,
7007                                            LValue Src) {
7008     llvm::Value *Handle = nullptr;
7009     llvm::Constant *C =
7010         llvm::dyn_cast<llvm::Constant>(Src.getAddress(CGF).getPointer());
7011     // Lookup `addrspacecast` through the constant pointer if any.
7012     if (auto *ASC = llvm::dyn_cast_or_null<llvm::AddrSpaceCastOperator>(C))
7013       C = llvm::cast<llvm::Constant>(ASC->getPointerOperand());
7014     if (auto *GV = llvm::dyn_cast_or_null<llvm::GlobalVariable>(C)) {
7015       // Load the handle from the specific global variable using
7016       // `nvvm.texsurf.handle.internal` intrinsic.
7017       Handle = CGF.EmitRuntimeCall(
7018           CGF.CGM.getIntrinsic(llvm::Intrinsic::nvvm_texsurf_handle_internal,
7019                                {GV->getType()}),
7020           {GV}, "texsurf_handle");
7021     } else
7022       Handle = CGF.EmitLoadOfScalar(Src, SourceLocation());
7023     CGF.EmitStoreOfScalar(Handle, Dst);
7024   }
7025 };
7026 
7027 /// Checks if the type is unsupported directly by the current target.
isUnsupportedType(QualType T) const7028 bool NVPTXABIInfo::isUnsupportedType(QualType T) const {
7029   ASTContext &Context = getContext();
7030   if (!Context.getTargetInfo().hasFloat16Type() && T->isFloat16Type())
7031     return true;
7032   if (!Context.getTargetInfo().hasFloat128Type() &&
7033       (T->isFloat128Type() ||
7034        (T->isRealFloatingType() && Context.getTypeSize(T) == 128)))
7035     return true;
7036   if (const auto *EIT = T->getAs<ExtIntType>())
7037     return EIT->getNumBits() >
7038            (Context.getTargetInfo().hasInt128Type() ? 128U : 64U);
7039   if (!Context.getTargetInfo().hasInt128Type() && T->isIntegerType() &&
7040       Context.getTypeSize(T) > 64U)
7041     return true;
7042   if (const auto *AT = T->getAsArrayTypeUnsafe())
7043     return isUnsupportedType(AT->getElementType());
7044   const auto *RT = T->getAs<RecordType>();
7045   if (!RT)
7046     return false;
7047   const RecordDecl *RD = RT->getDecl();
7048 
7049   // If this is a C++ record, check the bases first.
7050   if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
7051     for (const CXXBaseSpecifier &I : CXXRD->bases())
7052       if (isUnsupportedType(I.getType()))
7053         return true;
7054 
7055   for (const FieldDecl *I : RD->fields())
7056     if (isUnsupportedType(I->getType()))
7057       return true;
7058   return false;
7059 }
7060 
7061 /// Coerce the given type into an array with maximum allowed size of elements.
coerceToIntArrayWithLimit(QualType Ty,unsigned MaxSize) const7062 ABIArgInfo NVPTXABIInfo::coerceToIntArrayWithLimit(QualType Ty,
7063                                                    unsigned MaxSize) const {
7064   // Alignment and Size are measured in bits.
7065   const uint64_t Size = getContext().getTypeSize(Ty);
7066   const uint64_t Alignment = getContext().getTypeAlign(Ty);
7067   const unsigned Div = std::min<unsigned>(MaxSize, Alignment);
7068   llvm::Type *IntType = llvm::Type::getIntNTy(getVMContext(), Div);
7069   const uint64_t NumElements = (Size + Div - 1) / Div;
7070   return ABIArgInfo::getDirect(llvm::ArrayType::get(IntType, NumElements));
7071 }
7072 
classifyReturnType(QualType RetTy) const7073 ABIArgInfo NVPTXABIInfo::classifyReturnType(QualType RetTy) const {
7074   if (RetTy->isVoidType())
7075     return ABIArgInfo::getIgnore();
7076 
7077   if (getContext().getLangOpts().OpenMP &&
7078       getContext().getLangOpts().OpenMPIsDevice && isUnsupportedType(RetTy))
7079     return coerceToIntArrayWithLimit(RetTy, 64);
7080 
7081   // note: this is different from default ABI
7082   if (!RetTy->isScalarType())
7083     return ABIArgInfo::getDirect();
7084 
7085   // Treat an enum type as its underlying type.
7086   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
7087     RetTy = EnumTy->getDecl()->getIntegerType();
7088 
7089   return (isPromotableIntegerTypeForABI(RetTy) ? ABIArgInfo::getExtend(RetTy)
7090                                                : ABIArgInfo::getDirect());
7091 }
7092 
classifyArgumentType(QualType Ty) const7093 ABIArgInfo NVPTXABIInfo::classifyArgumentType(QualType Ty) const {
7094   // Treat an enum type as its underlying type.
7095   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
7096     Ty = EnumTy->getDecl()->getIntegerType();
7097 
7098   // Return aggregates type as indirect by value
7099   if (isAggregateTypeForABI(Ty)) {
7100     // Under CUDA device compilation, tex/surf builtin types are replaced with
7101     // object types and passed directly.
7102     if (getContext().getLangOpts().CUDAIsDevice) {
7103       if (Ty->isCUDADeviceBuiltinSurfaceType())
7104         return ABIArgInfo::getDirect(
7105             CGInfo.getCUDADeviceBuiltinSurfaceDeviceType());
7106       if (Ty->isCUDADeviceBuiltinTextureType())
7107         return ABIArgInfo::getDirect(
7108             CGInfo.getCUDADeviceBuiltinTextureDeviceType());
7109     }
7110     return getNaturalAlignIndirect(Ty, /* byval */ true);
7111   }
7112 
7113   if (const auto *EIT = Ty->getAs<ExtIntType>()) {
7114     if ((EIT->getNumBits() > 128) ||
7115         (!getContext().getTargetInfo().hasInt128Type() &&
7116          EIT->getNumBits() > 64))
7117       return getNaturalAlignIndirect(Ty, /* byval */ true);
7118   }
7119 
7120   return (isPromotableIntegerTypeForABI(Ty) ? ABIArgInfo::getExtend(Ty)
7121                                             : ABIArgInfo::getDirect());
7122 }
7123 
computeInfo(CGFunctionInfo & FI) const7124 void NVPTXABIInfo::computeInfo(CGFunctionInfo &FI) const {
7125   if (!getCXXABI().classifyReturnType(FI))
7126     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
7127   for (auto &I : FI.arguments())
7128     I.info = classifyArgumentType(I.type);
7129 
7130   // Always honor user-specified calling convention.
7131   if (FI.getCallingConvention() != llvm::CallingConv::C)
7132     return;
7133 
7134   FI.setEffectiveCallingConvention(getRuntimeCC());
7135 }
7136 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const7137 Address NVPTXABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
7138                                 QualType Ty) const {
7139   llvm_unreachable("NVPTX does not support varargs");
7140 }
7141 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & M) const7142 void NVPTXTargetCodeGenInfo::setTargetAttributes(
7143     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &M) const {
7144   if (GV->isDeclaration())
7145     return;
7146   const VarDecl *VD = dyn_cast_or_null<VarDecl>(D);
7147   if (VD) {
7148     if (M.getLangOpts().CUDA) {
7149       if (VD->getType()->isCUDADeviceBuiltinSurfaceType())
7150         addNVVMMetadata(GV, "surface", 1);
7151       else if (VD->getType()->isCUDADeviceBuiltinTextureType())
7152         addNVVMMetadata(GV, "texture", 1);
7153       return;
7154     }
7155   }
7156 
7157   const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
7158   if (!FD) return;
7159 
7160   llvm::Function *F = cast<llvm::Function>(GV);
7161 
7162   // Perform special handling in OpenCL mode
7163   if (M.getLangOpts().OpenCL) {
7164     // Use OpenCL function attributes to check for kernel functions
7165     // By default, all functions are device functions
7166     if (FD->hasAttr<OpenCLKernelAttr>()) {
7167       // OpenCL __kernel functions get kernel metadata
7168       // Create !{<func-ref>, metadata !"kernel", i32 1} node
7169       addNVVMMetadata(F, "kernel", 1);
7170       // And kernel functions are not subject to inlining
7171       F->addFnAttr(llvm::Attribute::NoInline);
7172     }
7173   }
7174 
7175   // Perform special handling in CUDA mode.
7176   if (M.getLangOpts().CUDA) {
7177     // CUDA __global__ functions get a kernel metadata entry.  Since
7178     // __global__ functions cannot be called from the device, we do not
7179     // need to set the noinline attribute.
7180     if (FD->hasAttr<CUDAGlobalAttr>()) {
7181       // Create !{<func-ref>, metadata !"kernel", i32 1} node
7182       addNVVMMetadata(F, "kernel", 1);
7183     }
7184     if (CUDALaunchBoundsAttr *Attr = FD->getAttr<CUDALaunchBoundsAttr>()) {
7185       // Create !{<func-ref>, metadata !"maxntidx", i32 <val>} node
7186       llvm::APSInt MaxThreads(32);
7187       MaxThreads = Attr->getMaxThreads()->EvaluateKnownConstInt(M.getContext());
7188       if (MaxThreads > 0)
7189         addNVVMMetadata(F, "maxntidx", MaxThreads.getExtValue());
7190 
7191       // min blocks is an optional argument for CUDALaunchBoundsAttr. If it was
7192       // not specified in __launch_bounds__ or if the user specified a 0 value,
7193       // we don't have to add a PTX directive.
7194       if (Attr->getMinBlocks()) {
7195         llvm::APSInt MinBlocks(32);
7196         MinBlocks = Attr->getMinBlocks()->EvaluateKnownConstInt(M.getContext());
7197         if (MinBlocks > 0)
7198           // Create !{<func-ref>, metadata !"minctasm", i32 <val>} node
7199           addNVVMMetadata(F, "minctasm", MinBlocks.getExtValue());
7200       }
7201     }
7202   }
7203 }
7204 
addNVVMMetadata(llvm::GlobalValue * GV,StringRef Name,int Operand)7205 void NVPTXTargetCodeGenInfo::addNVVMMetadata(llvm::GlobalValue *GV,
7206                                              StringRef Name, int Operand) {
7207   llvm::Module *M = GV->getParent();
7208   llvm::LLVMContext &Ctx = M->getContext();
7209 
7210   // Get "nvvm.annotations" metadata node
7211   llvm::NamedMDNode *MD = M->getOrInsertNamedMetadata("nvvm.annotations");
7212 
7213   llvm::Metadata *MDVals[] = {
7214       llvm::ConstantAsMetadata::get(GV), llvm::MDString::get(Ctx, Name),
7215       llvm::ConstantAsMetadata::get(
7216           llvm::ConstantInt::get(llvm::Type::getInt32Ty(Ctx), Operand))};
7217   // Append metadata to nvvm.annotations
7218   MD->addOperand(llvm::MDNode::get(Ctx, MDVals));
7219 }
7220 
shouldEmitStaticExternCAliases() const7221 bool NVPTXTargetCodeGenInfo::shouldEmitStaticExternCAliases() const {
7222   return false;
7223 }
7224 }
7225 
7226 //===----------------------------------------------------------------------===//
7227 // SystemZ ABI Implementation
7228 //===----------------------------------------------------------------------===//
7229 
7230 namespace {
7231 
7232 class SystemZABIInfo : public SwiftABIInfo {
7233   bool HasVector;
7234   bool IsSoftFloatABI;
7235 
7236 public:
SystemZABIInfo(CodeGenTypes & CGT,bool HV,bool SF)7237   SystemZABIInfo(CodeGenTypes &CGT, bool HV, bool SF)
7238     : SwiftABIInfo(CGT), HasVector(HV), IsSoftFloatABI(SF) {}
7239 
7240   bool isPromotableIntegerTypeForABI(QualType Ty) const;
7241   bool isCompoundType(QualType Ty) const;
7242   bool isVectorArgumentType(QualType Ty) const;
7243   bool isFPArgumentType(QualType Ty) const;
7244   QualType GetSingleElementType(QualType Ty) const;
7245 
7246   ABIArgInfo classifyReturnType(QualType RetTy) const;
7247   ABIArgInfo classifyArgumentType(QualType ArgTy) const;
7248 
computeInfo(CGFunctionInfo & FI) const7249   void computeInfo(CGFunctionInfo &FI) const override {
7250     if (!getCXXABI().classifyReturnType(FI))
7251       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
7252     for (auto &I : FI.arguments())
7253       I.info = classifyArgumentType(I.type);
7254   }
7255 
7256   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
7257                     QualType Ty) const override;
7258 
shouldPassIndirectlyForSwift(ArrayRef<llvm::Type * > scalars,bool asReturnValue) const7259   bool shouldPassIndirectlyForSwift(ArrayRef<llvm::Type*> scalars,
7260                                     bool asReturnValue) const override {
7261     return occupiesMoreThan(CGT, scalars, /*total*/ 4);
7262   }
isSwiftErrorInRegister() const7263   bool isSwiftErrorInRegister() const override {
7264     return false;
7265   }
7266 };
7267 
7268 class SystemZTargetCodeGenInfo : public TargetCodeGenInfo {
7269 public:
SystemZTargetCodeGenInfo(CodeGenTypes & CGT,bool HasVector,bool SoftFloatABI)7270   SystemZTargetCodeGenInfo(CodeGenTypes &CGT, bool HasVector, bool SoftFloatABI)
7271       : TargetCodeGenInfo(
7272             std::make_unique<SystemZABIInfo>(CGT, HasVector, SoftFloatABI)) {}
7273 
testFPKind(llvm::Value * V,unsigned BuiltinID,CGBuilderTy & Builder,CodeGenModule & CGM) const7274   llvm::Value *testFPKind(llvm::Value *V, unsigned BuiltinID,
7275                           CGBuilderTy &Builder,
7276                           CodeGenModule &CGM) const override {
7277     assert(V->getType()->isFloatingPointTy() && "V should have an FP type.");
7278     // Only use TDC in constrained FP mode.
7279     if (!Builder.getIsFPConstrained())
7280       return nullptr;
7281 
7282     llvm::Type *Ty = V->getType();
7283     if (Ty->isFloatTy() || Ty->isDoubleTy() || Ty->isFP128Ty()) {
7284       llvm::Module &M = CGM.getModule();
7285       auto &Ctx = M.getContext();
7286       llvm::Function *TDCFunc =
7287           llvm::Intrinsic::getDeclaration(&M, llvm::Intrinsic::s390_tdc, Ty);
7288       unsigned TDCBits = 0;
7289       switch (BuiltinID) {
7290       case Builtin::BI__builtin_isnan:
7291         TDCBits = 0xf;
7292         break;
7293       case Builtin::BIfinite:
7294       case Builtin::BI__finite:
7295       case Builtin::BIfinitef:
7296       case Builtin::BI__finitef:
7297       case Builtin::BIfinitel:
7298       case Builtin::BI__finitel:
7299       case Builtin::BI__builtin_isfinite:
7300         TDCBits = 0xfc0;
7301         break;
7302       case Builtin::BI__builtin_isinf:
7303         TDCBits = 0x30;
7304         break;
7305       default:
7306         break;
7307       }
7308       if (TDCBits)
7309         return Builder.CreateCall(
7310             TDCFunc,
7311             {V, llvm::ConstantInt::get(llvm::Type::getInt64Ty(Ctx), TDCBits)});
7312     }
7313     return nullptr;
7314   }
7315 };
7316 }
7317 
isPromotableIntegerTypeForABI(QualType Ty) const7318 bool SystemZABIInfo::isPromotableIntegerTypeForABI(QualType Ty) const {
7319   // Treat an enum type as its underlying type.
7320   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
7321     Ty = EnumTy->getDecl()->getIntegerType();
7322 
7323   // Promotable integer types are required to be promoted by the ABI.
7324   if (ABIInfo::isPromotableIntegerTypeForABI(Ty))
7325     return true;
7326 
7327   if (const auto *EIT = Ty->getAs<ExtIntType>())
7328     if (EIT->getNumBits() < 64)
7329       return true;
7330 
7331   // 32-bit values must also be promoted.
7332   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
7333     switch (BT->getKind()) {
7334     case BuiltinType::Int:
7335     case BuiltinType::UInt:
7336       return true;
7337     default:
7338       return false;
7339     }
7340   return false;
7341 }
7342 
isCompoundType(QualType Ty) const7343 bool SystemZABIInfo::isCompoundType(QualType Ty) const {
7344   return (Ty->isAnyComplexType() ||
7345           Ty->isVectorType() ||
7346           isAggregateTypeForABI(Ty));
7347 }
7348 
isVectorArgumentType(QualType Ty) const7349 bool SystemZABIInfo::isVectorArgumentType(QualType Ty) const {
7350   return (HasVector &&
7351           Ty->isVectorType() &&
7352           getContext().getTypeSize(Ty) <= 128);
7353 }
7354 
isFPArgumentType(QualType Ty) const7355 bool SystemZABIInfo::isFPArgumentType(QualType Ty) const {
7356   if (IsSoftFloatABI)
7357     return false;
7358 
7359   if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
7360     switch (BT->getKind()) {
7361     case BuiltinType::Float:
7362     case BuiltinType::Double:
7363       return true;
7364     default:
7365       return false;
7366     }
7367 
7368   return false;
7369 }
7370 
GetSingleElementType(QualType Ty) const7371 QualType SystemZABIInfo::GetSingleElementType(QualType Ty) const {
7372   const RecordType *RT = Ty->getAs<RecordType>();
7373 
7374   if (RT && RT->isStructureOrClassType()) {
7375     const RecordDecl *RD = RT->getDecl();
7376     QualType Found;
7377 
7378     // If this is a C++ record, check the bases first.
7379     if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
7380       for (const auto &I : CXXRD->bases()) {
7381         QualType Base = I.getType();
7382 
7383         // Empty bases don't affect things either way.
7384         if (isEmptyRecord(getContext(), Base, true))
7385           continue;
7386 
7387         if (!Found.isNull())
7388           return Ty;
7389         Found = GetSingleElementType(Base);
7390       }
7391 
7392     // Check the fields.
7393     for (const auto *FD : RD->fields()) {
7394       // For compatibility with GCC, ignore empty bitfields in C++ mode.
7395       // Unlike isSingleElementStruct(), empty structure and array fields
7396       // do count.  So do anonymous bitfields that aren't zero-sized.
7397       if (getContext().getLangOpts().CPlusPlus &&
7398           FD->isZeroLengthBitField(getContext()))
7399         continue;
7400       // Like isSingleElementStruct(), ignore C++20 empty data members.
7401       if (FD->hasAttr<NoUniqueAddressAttr>() &&
7402           isEmptyRecord(getContext(), FD->getType(), true))
7403         continue;
7404 
7405       // Unlike isSingleElementStruct(), arrays do not count.
7406       // Nested structures still do though.
7407       if (!Found.isNull())
7408         return Ty;
7409       Found = GetSingleElementType(FD->getType());
7410     }
7411 
7412     // Unlike isSingleElementStruct(), trailing padding is allowed.
7413     // An 8-byte aligned struct s { float f; } is passed as a double.
7414     if (!Found.isNull())
7415       return Found;
7416   }
7417 
7418   return Ty;
7419 }
7420 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const7421 Address SystemZABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
7422                                   QualType Ty) const {
7423   // Assume that va_list type is correct; should be pointer to LLVM type:
7424   // struct {
7425   //   i64 __gpr;
7426   //   i64 __fpr;
7427   //   i8 *__overflow_arg_area;
7428   //   i8 *__reg_save_area;
7429   // };
7430 
7431   // Every non-vector argument occupies 8 bytes and is passed by preference
7432   // in either GPRs or FPRs.  Vector arguments occupy 8 or 16 bytes and are
7433   // always passed on the stack.
7434   Ty = getContext().getCanonicalType(Ty);
7435   auto TyInfo = getContext().getTypeInfoInChars(Ty);
7436   llvm::Type *ArgTy = CGF.ConvertTypeForMem(Ty);
7437   llvm::Type *DirectTy = ArgTy;
7438   ABIArgInfo AI = classifyArgumentType(Ty);
7439   bool IsIndirect = AI.isIndirect();
7440   bool InFPRs = false;
7441   bool IsVector = false;
7442   CharUnits UnpaddedSize;
7443   CharUnits DirectAlign;
7444   if (IsIndirect) {
7445     DirectTy = llvm::PointerType::getUnqual(DirectTy);
7446     UnpaddedSize = DirectAlign = CharUnits::fromQuantity(8);
7447   } else {
7448     if (AI.getCoerceToType())
7449       ArgTy = AI.getCoerceToType();
7450     InFPRs = (!IsSoftFloatABI && (ArgTy->isFloatTy() || ArgTy->isDoubleTy()));
7451     IsVector = ArgTy->isVectorTy();
7452     UnpaddedSize = TyInfo.Width;
7453     DirectAlign = TyInfo.Align;
7454   }
7455   CharUnits PaddedSize = CharUnits::fromQuantity(8);
7456   if (IsVector && UnpaddedSize > PaddedSize)
7457     PaddedSize = CharUnits::fromQuantity(16);
7458   assert((UnpaddedSize <= PaddedSize) && "Invalid argument size.");
7459 
7460   CharUnits Padding = (PaddedSize - UnpaddedSize);
7461 
7462   llvm::Type *IndexTy = CGF.Int64Ty;
7463   llvm::Value *PaddedSizeV =
7464     llvm::ConstantInt::get(IndexTy, PaddedSize.getQuantity());
7465 
7466   if (IsVector) {
7467     // Work out the address of a vector argument on the stack.
7468     // Vector arguments are always passed in the high bits of a
7469     // single (8 byte) or double (16 byte) stack slot.
7470     Address OverflowArgAreaPtr =
7471         CGF.Builder.CreateStructGEP(VAListAddr, 2, "overflow_arg_area_ptr");
7472     Address OverflowArgArea =
7473       Address(CGF.Builder.CreateLoad(OverflowArgAreaPtr, "overflow_arg_area"),
7474               TyInfo.Align);
7475     Address MemAddr =
7476       CGF.Builder.CreateElementBitCast(OverflowArgArea, DirectTy, "mem_addr");
7477 
7478     // Update overflow_arg_area_ptr pointer
7479     llvm::Value *NewOverflowArgArea =
7480       CGF.Builder.CreateGEP(OverflowArgArea.getElementType(),
7481                             OverflowArgArea.getPointer(), PaddedSizeV,
7482                             "overflow_arg_area");
7483     CGF.Builder.CreateStore(NewOverflowArgArea, OverflowArgAreaPtr);
7484 
7485     return MemAddr;
7486   }
7487 
7488   assert(PaddedSize.getQuantity() == 8);
7489 
7490   unsigned MaxRegs, RegCountField, RegSaveIndex;
7491   CharUnits RegPadding;
7492   if (InFPRs) {
7493     MaxRegs = 4; // Maximum of 4 FPR arguments
7494     RegCountField = 1; // __fpr
7495     RegSaveIndex = 16; // save offset for f0
7496     RegPadding = CharUnits(); // floats are passed in the high bits of an FPR
7497   } else {
7498     MaxRegs = 5; // Maximum of 5 GPR arguments
7499     RegCountField = 0; // __gpr
7500     RegSaveIndex = 2; // save offset for r2
7501     RegPadding = Padding; // values are passed in the low bits of a GPR
7502   }
7503 
7504   Address RegCountPtr =
7505       CGF.Builder.CreateStructGEP(VAListAddr, RegCountField, "reg_count_ptr");
7506   llvm::Value *RegCount = CGF.Builder.CreateLoad(RegCountPtr, "reg_count");
7507   llvm::Value *MaxRegsV = llvm::ConstantInt::get(IndexTy, MaxRegs);
7508   llvm::Value *InRegs = CGF.Builder.CreateICmpULT(RegCount, MaxRegsV,
7509                                                  "fits_in_regs");
7510 
7511   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
7512   llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
7513   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
7514   CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
7515 
7516   // Emit code to load the value if it was passed in registers.
7517   CGF.EmitBlock(InRegBlock);
7518 
7519   // Work out the address of an argument register.
7520   llvm::Value *ScaledRegCount =
7521     CGF.Builder.CreateMul(RegCount, PaddedSizeV, "scaled_reg_count");
7522   llvm::Value *RegBase =
7523     llvm::ConstantInt::get(IndexTy, RegSaveIndex * PaddedSize.getQuantity()
7524                                       + RegPadding.getQuantity());
7525   llvm::Value *RegOffset =
7526     CGF.Builder.CreateAdd(ScaledRegCount, RegBase, "reg_offset");
7527   Address RegSaveAreaPtr =
7528       CGF.Builder.CreateStructGEP(VAListAddr, 3, "reg_save_area_ptr");
7529   llvm::Value *RegSaveArea =
7530     CGF.Builder.CreateLoad(RegSaveAreaPtr, "reg_save_area");
7531   Address RawRegAddr(CGF.Builder.CreateGEP(CGF.Int8Ty, RegSaveArea, RegOffset,
7532                                            "raw_reg_addr"),
7533                      PaddedSize);
7534   Address RegAddr =
7535     CGF.Builder.CreateElementBitCast(RawRegAddr, DirectTy, "reg_addr");
7536 
7537   // Update the register count
7538   llvm::Value *One = llvm::ConstantInt::get(IndexTy, 1);
7539   llvm::Value *NewRegCount =
7540     CGF.Builder.CreateAdd(RegCount, One, "reg_count");
7541   CGF.Builder.CreateStore(NewRegCount, RegCountPtr);
7542   CGF.EmitBranch(ContBlock);
7543 
7544   // Emit code to load the value if it was passed in memory.
7545   CGF.EmitBlock(InMemBlock);
7546 
7547   // Work out the address of a stack argument.
7548   Address OverflowArgAreaPtr =
7549       CGF.Builder.CreateStructGEP(VAListAddr, 2, "overflow_arg_area_ptr");
7550   Address OverflowArgArea =
7551     Address(CGF.Builder.CreateLoad(OverflowArgAreaPtr, "overflow_arg_area"),
7552             PaddedSize);
7553   Address RawMemAddr =
7554     CGF.Builder.CreateConstByteGEP(OverflowArgArea, Padding, "raw_mem_addr");
7555   Address MemAddr =
7556     CGF.Builder.CreateElementBitCast(RawMemAddr, DirectTy, "mem_addr");
7557 
7558   // Update overflow_arg_area_ptr pointer
7559   llvm::Value *NewOverflowArgArea =
7560     CGF.Builder.CreateGEP(OverflowArgArea.getElementType(),
7561                           OverflowArgArea.getPointer(), PaddedSizeV,
7562                           "overflow_arg_area");
7563   CGF.Builder.CreateStore(NewOverflowArgArea, OverflowArgAreaPtr);
7564   CGF.EmitBranch(ContBlock);
7565 
7566   // Return the appropriate result.
7567   CGF.EmitBlock(ContBlock);
7568   Address ResAddr = emitMergePHI(CGF, RegAddr, InRegBlock,
7569                                  MemAddr, InMemBlock, "va_arg.addr");
7570 
7571   if (IsIndirect)
7572     ResAddr = Address(CGF.Builder.CreateLoad(ResAddr, "indirect_arg"),
7573                       TyInfo.Align);
7574 
7575   return ResAddr;
7576 }
7577 
classifyReturnType(QualType RetTy) const7578 ABIArgInfo SystemZABIInfo::classifyReturnType(QualType RetTy) const {
7579   if (RetTy->isVoidType())
7580     return ABIArgInfo::getIgnore();
7581   if (isVectorArgumentType(RetTy))
7582     return ABIArgInfo::getDirect();
7583   if (isCompoundType(RetTy) || getContext().getTypeSize(RetTy) > 64)
7584     return getNaturalAlignIndirect(RetTy);
7585   return (isPromotableIntegerTypeForABI(RetTy) ? ABIArgInfo::getExtend(RetTy)
7586                                                : ABIArgInfo::getDirect());
7587 }
7588 
classifyArgumentType(QualType Ty) const7589 ABIArgInfo SystemZABIInfo::classifyArgumentType(QualType Ty) const {
7590   // Handle the generic C++ ABI.
7591   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
7592     return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
7593 
7594   // Integers and enums are extended to full register width.
7595   if (isPromotableIntegerTypeForABI(Ty))
7596     return ABIArgInfo::getExtend(Ty);
7597 
7598   // Handle vector types and vector-like structure types.  Note that
7599   // as opposed to float-like structure types, we do not allow any
7600   // padding for vector-like structures, so verify the sizes match.
7601   uint64_t Size = getContext().getTypeSize(Ty);
7602   QualType SingleElementTy = GetSingleElementType(Ty);
7603   if (isVectorArgumentType(SingleElementTy) &&
7604       getContext().getTypeSize(SingleElementTy) == Size)
7605     return ABIArgInfo::getDirect(CGT.ConvertType(SingleElementTy));
7606 
7607   // Values that are not 1, 2, 4 or 8 bytes in size are passed indirectly.
7608   if (Size != 8 && Size != 16 && Size != 32 && Size != 64)
7609     return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
7610 
7611   // Handle small structures.
7612   if (const RecordType *RT = Ty->getAs<RecordType>()) {
7613     // Structures with flexible arrays have variable length, so really
7614     // fail the size test above.
7615     const RecordDecl *RD = RT->getDecl();
7616     if (RD->hasFlexibleArrayMember())
7617       return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
7618 
7619     // The structure is passed as an unextended integer, a float, or a double.
7620     llvm::Type *PassTy;
7621     if (isFPArgumentType(SingleElementTy)) {
7622       assert(Size == 32 || Size == 64);
7623       if (Size == 32)
7624         PassTy = llvm::Type::getFloatTy(getVMContext());
7625       else
7626         PassTy = llvm::Type::getDoubleTy(getVMContext());
7627     } else
7628       PassTy = llvm::IntegerType::get(getVMContext(), Size);
7629     return ABIArgInfo::getDirect(PassTy);
7630   }
7631 
7632   // Non-structure compounds are passed indirectly.
7633   if (isCompoundType(Ty))
7634     return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
7635 
7636   return ABIArgInfo::getDirect(nullptr);
7637 }
7638 
7639 //===----------------------------------------------------------------------===//
7640 // MSP430 ABI Implementation
7641 //===----------------------------------------------------------------------===//
7642 
7643 namespace {
7644 
7645 class MSP430ABIInfo : public DefaultABIInfo {
complexArgInfo()7646   static ABIArgInfo complexArgInfo() {
7647     ABIArgInfo Info = ABIArgInfo::getDirect();
7648     Info.setCanBeFlattened(false);
7649     return Info;
7650   }
7651 
7652 public:
MSP430ABIInfo(CodeGenTypes & CGT)7653   MSP430ABIInfo(CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
7654 
classifyReturnType(QualType RetTy) const7655   ABIArgInfo classifyReturnType(QualType RetTy) const {
7656     if (RetTy->isAnyComplexType())
7657       return complexArgInfo();
7658 
7659     return DefaultABIInfo::classifyReturnType(RetTy);
7660   }
7661 
classifyArgumentType(QualType RetTy) const7662   ABIArgInfo classifyArgumentType(QualType RetTy) const {
7663     if (RetTy->isAnyComplexType())
7664       return complexArgInfo();
7665 
7666     return DefaultABIInfo::classifyArgumentType(RetTy);
7667   }
7668 
7669   // Just copy the original implementations because
7670   // DefaultABIInfo::classify{Return,Argument}Type() are not virtual
computeInfo(CGFunctionInfo & FI) const7671   void computeInfo(CGFunctionInfo &FI) const override {
7672     if (!getCXXABI().classifyReturnType(FI))
7673       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
7674     for (auto &I : FI.arguments())
7675       I.info = classifyArgumentType(I.type);
7676   }
7677 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const7678   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
7679                     QualType Ty) const override {
7680     return EmitVAArgInstr(CGF, VAListAddr, Ty, classifyArgumentType(Ty));
7681   }
7682 };
7683 
7684 class MSP430TargetCodeGenInfo : public TargetCodeGenInfo {
7685 public:
MSP430TargetCodeGenInfo(CodeGenTypes & CGT)7686   MSP430TargetCodeGenInfo(CodeGenTypes &CGT)
7687       : TargetCodeGenInfo(std::make_unique<MSP430ABIInfo>(CGT)) {}
7688   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
7689                            CodeGen::CodeGenModule &M) const override;
7690 };
7691 
7692 }
7693 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & M) const7694 void MSP430TargetCodeGenInfo::setTargetAttributes(
7695     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &M) const {
7696   if (GV->isDeclaration())
7697     return;
7698   if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D)) {
7699     const auto *InterruptAttr = FD->getAttr<MSP430InterruptAttr>();
7700     if (!InterruptAttr)
7701       return;
7702 
7703     // Handle 'interrupt' attribute:
7704     llvm::Function *F = cast<llvm::Function>(GV);
7705 
7706     // Step 1: Set ISR calling convention.
7707     F->setCallingConv(llvm::CallingConv::MSP430_INTR);
7708 
7709     // Step 2: Add attributes goodness.
7710     F->addFnAttr(llvm::Attribute::NoInline);
7711     F->addFnAttr("interrupt", llvm::utostr(InterruptAttr->getNumber()));
7712   }
7713 }
7714 
7715 //===----------------------------------------------------------------------===//
7716 // MIPS ABI Implementation.  This works for both little-endian and
7717 // big-endian variants.
7718 //===----------------------------------------------------------------------===//
7719 
7720 namespace {
7721 class MipsABIInfo : public ABIInfo {
7722   bool IsO32;
7723   unsigned MinABIStackAlignInBytes, StackAlignInBytes;
7724   void CoerceToIntArgs(uint64_t TySize,
7725                        SmallVectorImpl<llvm::Type *> &ArgList) const;
7726   llvm::Type* HandleAggregates(QualType Ty, uint64_t TySize) const;
7727   llvm::Type* returnAggregateInRegs(QualType RetTy, uint64_t Size) const;
7728   llvm::Type* getPaddingType(uint64_t Align, uint64_t Offset) const;
7729 public:
MipsABIInfo(CodeGenTypes & CGT,bool _IsO32)7730   MipsABIInfo(CodeGenTypes &CGT, bool _IsO32) :
7731     ABIInfo(CGT), IsO32(_IsO32), MinABIStackAlignInBytes(IsO32 ? 4 : 8),
7732     StackAlignInBytes(IsO32 ? 8 : 16) {}
7733 
7734   ABIArgInfo classifyReturnType(QualType RetTy) const;
7735   ABIArgInfo classifyArgumentType(QualType RetTy, uint64_t &Offset) const;
7736   void computeInfo(CGFunctionInfo &FI) const override;
7737   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
7738                     QualType Ty) const override;
7739   ABIArgInfo extendType(QualType Ty) const;
7740 };
7741 
7742 class MIPSTargetCodeGenInfo : public TargetCodeGenInfo {
7743   unsigned SizeOfUnwindException;
7744 public:
MIPSTargetCodeGenInfo(CodeGenTypes & CGT,bool IsO32)7745   MIPSTargetCodeGenInfo(CodeGenTypes &CGT, bool IsO32)
7746       : TargetCodeGenInfo(std::make_unique<MipsABIInfo>(CGT, IsO32)),
7747         SizeOfUnwindException(IsO32 ? 24 : 32) {}
7748 
getDwarfEHStackPointer(CodeGen::CodeGenModule & CGM) const7749   int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
7750     return 29;
7751   }
7752 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & CGM) const7753   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
7754                            CodeGen::CodeGenModule &CGM) const override {
7755     const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
7756     if (!FD) return;
7757     llvm::Function *Fn = cast<llvm::Function>(GV);
7758 
7759     if (FD->hasAttr<MipsLongCallAttr>())
7760       Fn->addFnAttr("long-call");
7761     else if (FD->hasAttr<MipsShortCallAttr>())
7762       Fn->addFnAttr("short-call");
7763 
7764     // Other attributes do not have a meaning for declarations.
7765     if (GV->isDeclaration())
7766       return;
7767 
7768     if (FD->hasAttr<Mips16Attr>()) {
7769       Fn->addFnAttr("mips16");
7770     }
7771     else if (FD->hasAttr<NoMips16Attr>()) {
7772       Fn->addFnAttr("nomips16");
7773     }
7774 
7775     if (FD->hasAttr<MicroMipsAttr>())
7776       Fn->addFnAttr("micromips");
7777     else if (FD->hasAttr<NoMicroMipsAttr>())
7778       Fn->addFnAttr("nomicromips");
7779 
7780     const MipsInterruptAttr *Attr = FD->getAttr<MipsInterruptAttr>();
7781     if (!Attr)
7782       return;
7783 
7784     const char *Kind;
7785     switch (Attr->getInterrupt()) {
7786     case MipsInterruptAttr::eic:     Kind = "eic"; break;
7787     case MipsInterruptAttr::sw0:     Kind = "sw0"; break;
7788     case MipsInterruptAttr::sw1:     Kind = "sw1"; break;
7789     case MipsInterruptAttr::hw0:     Kind = "hw0"; break;
7790     case MipsInterruptAttr::hw1:     Kind = "hw1"; break;
7791     case MipsInterruptAttr::hw2:     Kind = "hw2"; break;
7792     case MipsInterruptAttr::hw3:     Kind = "hw3"; break;
7793     case MipsInterruptAttr::hw4:     Kind = "hw4"; break;
7794     case MipsInterruptAttr::hw5:     Kind = "hw5"; break;
7795     }
7796 
7797     Fn->addFnAttr("interrupt", Kind);
7798 
7799   }
7800 
7801   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
7802                                llvm::Value *Address) const override;
7803 
getSizeOfUnwindException() const7804   unsigned getSizeOfUnwindException() const override {
7805     return SizeOfUnwindException;
7806   }
7807 };
7808 }
7809 
CoerceToIntArgs(uint64_t TySize,SmallVectorImpl<llvm::Type * > & ArgList) const7810 void MipsABIInfo::CoerceToIntArgs(
7811     uint64_t TySize, SmallVectorImpl<llvm::Type *> &ArgList) const {
7812   llvm::IntegerType *IntTy =
7813     llvm::IntegerType::get(getVMContext(), MinABIStackAlignInBytes * 8);
7814 
7815   // Add (TySize / MinABIStackAlignInBytes) args of IntTy.
7816   for (unsigned N = TySize / (MinABIStackAlignInBytes * 8); N; --N)
7817     ArgList.push_back(IntTy);
7818 
7819   // If necessary, add one more integer type to ArgList.
7820   unsigned R = TySize % (MinABIStackAlignInBytes * 8);
7821 
7822   if (R)
7823     ArgList.push_back(llvm::IntegerType::get(getVMContext(), R));
7824 }
7825 
7826 // In N32/64, an aligned double precision floating point field is passed in
7827 // a register.
HandleAggregates(QualType Ty,uint64_t TySize) const7828 llvm::Type* MipsABIInfo::HandleAggregates(QualType Ty, uint64_t TySize) const {
7829   SmallVector<llvm::Type*, 8> ArgList, IntArgList;
7830 
7831   if (IsO32) {
7832     CoerceToIntArgs(TySize, ArgList);
7833     return llvm::StructType::get(getVMContext(), ArgList);
7834   }
7835 
7836   if (Ty->isComplexType())
7837     return CGT.ConvertType(Ty);
7838 
7839   const RecordType *RT = Ty->getAs<RecordType>();
7840 
7841   // Unions/vectors are passed in integer registers.
7842   if (!RT || !RT->isStructureOrClassType()) {
7843     CoerceToIntArgs(TySize, ArgList);
7844     return llvm::StructType::get(getVMContext(), ArgList);
7845   }
7846 
7847   const RecordDecl *RD = RT->getDecl();
7848   const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
7849   assert(!(TySize % 8) && "Size of structure must be multiple of 8.");
7850 
7851   uint64_t LastOffset = 0;
7852   unsigned idx = 0;
7853   llvm::IntegerType *I64 = llvm::IntegerType::get(getVMContext(), 64);
7854 
7855   // Iterate over fields in the struct/class and check if there are any aligned
7856   // double fields.
7857   for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
7858        i != e; ++i, ++idx) {
7859     const QualType Ty = i->getType();
7860     const BuiltinType *BT = Ty->getAs<BuiltinType>();
7861 
7862     if (!BT || BT->getKind() != BuiltinType::Double)
7863       continue;
7864 
7865     uint64_t Offset = Layout.getFieldOffset(idx);
7866     if (Offset % 64) // Ignore doubles that are not aligned.
7867       continue;
7868 
7869     // Add ((Offset - LastOffset) / 64) args of type i64.
7870     for (unsigned j = (Offset - LastOffset) / 64; j > 0; --j)
7871       ArgList.push_back(I64);
7872 
7873     // Add double type.
7874     ArgList.push_back(llvm::Type::getDoubleTy(getVMContext()));
7875     LastOffset = Offset + 64;
7876   }
7877 
7878   CoerceToIntArgs(TySize - LastOffset, IntArgList);
7879   ArgList.append(IntArgList.begin(), IntArgList.end());
7880 
7881   return llvm::StructType::get(getVMContext(), ArgList);
7882 }
7883 
getPaddingType(uint64_t OrigOffset,uint64_t Offset) const7884 llvm::Type *MipsABIInfo::getPaddingType(uint64_t OrigOffset,
7885                                         uint64_t Offset) const {
7886   if (OrigOffset + MinABIStackAlignInBytes > Offset)
7887     return nullptr;
7888 
7889   return llvm::IntegerType::get(getVMContext(), (Offset - OrigOffset) * 8);
7890 }
7891 
7892 ABIArgInfo
classifyArgumentType(QualType Ty,uint64_t & Offset) const7893 MipsABIInfo::classifyArgumentType(QualType Ty, uint64_t &Offset) const {
7894   Ty = useFirstFieldIfTransparentUnion(Ty);
7895 
7896   uint64_t OrigOffset = Offset;
7897   uint64_t TySize = getContext().getTypeSize(Ty);
7898   uint64_t Align = getContext().getTypeAlign(Ty) / 8;
7899 
7900   Align = std::min(std::max(Align, (uint64_t)MinABIStackAlignInBytes),
7901                    (uint64_t)StackAlignInBytes);
7902   unsigned CurrOffset = llvm::alignTo(Offset, Align);
7903   Offset = CurrOffset + llvm::alignTo(TySize, Align * 8) / 8;
7904 
7905   if (isAggregateTypeForABI(Ty) || Ty->isVectorType()) {
7906     // Ignore empty aggregates.
7907     if (TySize == 0)
7908       return ABIArgInfo::getIgnore();
7909 
7910     if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
7911       Offset = OrigOffset + MinABIStackAlignInBytes;
7912       return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
7913     }
7914 
7915     // If we have reached here, aggregates are passed directly by coercing to
7916     // another structure type. Padding is inserted if the offset of the
7917     // aggregate is unaligned.
7918     ABIArgInfo ArgInfo =
7919         ABIArgInfo::getDirect(HandleAggregates(Ty, TySize), 0,
7920                               getPaddingType(OrigOffset, CurrOffset));
7921     ArgInfo.setInReg(true);
7922     return ArgInfo;
7923   }
7924 
7925   // Treat an enum type as its underlying type.
7926   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
7927     Ty = EnumTy->getDecl()->getIntegerType();
7928 
7929   // Make sure we pass indirectly things that are too large.
7930   if (const auto *EIT = Ty->getAs<ExtIntType>())
7931     if (EIT->getNumBits() > 128 ||
7932         (EIT->getNumBits() > 64 &&
7933          !getContext().getTargetInfo().hasInt128Type()))
7934       return getNaturalAlignIndirect(Ty);
7935 
7936   // All integral types are promoted to the GPR width.
7937   if (Ty->isIntegralOrEnumerationType())
7938     return extendType(Ty);
7939 
7940   return ABIArgInfo::getDirect(
7941       nullptr, 0, IsO32 ? nullptr : getPaddingType(OrigOffset, CurrOffset));
7942 }
7943 
7944 llvm::Type*
returnAggregateInRegs(QualType RetTy,uint64_t Size) const7945 MipsABIInfo::returnAggregateInRegs(QualType RetTy, uint64_t Size) const {
7946   const RecordType *RT = RetTy->getAs<RecordType>();
7947   SmallVector<llvm::Type*, 8> RTList;
7948 
7949   if (RT && RT->isStructureOrClassType()) {
7950     const RecordDecl *RD = RT->getDecl();
7951     const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
7952     unsigned FieldCnt = Layout.getFieldCount();
7953 
7954     // N32/64 returns struct/classes in floating point registers if the
7955     // following conditions are met:
7956     // 1. The size of the struct/class is no larger than 128-bit.
7957     // 2. The struct/class has one or two fields all of which are floating
7958     //    point types.
7959     // 3. The offset of the first field is zero (this follows what gcc does).
7960     //
7961     // Any other composite results are returned in integer registers.
7962     //
7963     if (FieldCnt && (FieldCnt <= 2) && !Layout.getFieldOffset(0)) {
7964       RecordDecl::field_iterator b = RD->field_begin(), e = RD->field_end();
7965       for (; b != e; ++b) {
7966         const BuiltinType *BT = b->getType()->getAs<BuiltinType>();
7967 
7968         if (!BT || !BT->isFloatingPoint())
7969           break;
7970 
7971         RTList.push_back(CGT.ConvertType(b->getType()));
7972       }
7973 
7974       if (b == e)
7975         return llvm::StructType::get(getVMContext(), RTList,
7976                                      RD->hasAttr<PackedAttr>());
7977 
7978       RTList.clear();
7979     }
7980   }
7981 
7982   CoerceToIntArgs(Size, RTList);
7983   return llvm::StructType::get(getVMContext(), RTList);
7984 }
7985 
classifyReturnType(QualType RetTy) const7986 ABIArgInfo MipsABIInfo::classifyReturnType(QualType RetTy) const {
7987   uint64_t Size = getContext().getTypeSize(RetTy);
7988 
7989   if (RetTy->isVoidType())
7990     return ABIArgInfo::getIgnore();
7991 
7992   // O32 doesn't treat zero-sized structs differently from other structs.
7993   // However, N32/N64 ignores zero sized return values.
7994   if (!IsO32 && Size == 0)
7995     return ABIArgInfo::getIgnore();
7996 
7997   if (isAggregateTypeForABI(RetTy) || RetTy->isVectorType()) {
7998     if (Size <= 128) {
7999       if (RetTy->isAnyComplexType())
8000         return ABIArgInfo::getDirect();
8001 
8002       // O32 returns integer vectors in registers and N32/N64 returns all small
8003       // aggregates in registers.
8004       if (!IsO32 ||
8005           (RetTy->isVectorType() && !RetTy->hasFloatingRepresentation())) {
8006         ABIArgInfo ArgInfo =
8007             ABIArgInfo::getDirect(returnAggregateInRegs(RetTy, Size));
8008         ArgInfo.setInReg(true);
8009         return ArgInfo;
8010       }
8011     }
8012 
8013     return getNaturalAlignIndirect(RetTy);
8014   }
8015 
8016   // Treat an enum type as its underlying type.
8017   if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
8018     RetTy = EnumTy->getDecl()->getIntegerType();
8019 
8020   // Make sure we pass indirectly things that are too large.
8021   if (const auto *EIT = RetTy->getAs<ExtIntType>())
8022     if (EIT->getNumBits() > 128 ||
8023         (EIT->getNumBits() > 64 &&
8024          !getContext().getTargetInfo().hasInt128Type()))
8025       return getNaturalAlignIndirect(RetTy);
8026 
8027   if (isPromotableIntegerTypeForABI(RetTy))
8028     return ABIArgInfo::getExtend(RetTy);
8029 
8030   if ((RetTy->isUnsignedIntegerOrEnumerationType() ||
8031       RetTy->isSignedIntegerOrEnumerationType()) && Size == 32 && !IsO32)
8032     return ABIArgInfo::getSignExtend(RetTy);
8033 
8034   return ABIArgInfo::getDirect();
8035 }
8036 
computeInfo(CGFunctionInfo & FI) const8037 void MipsABIInfo::computeInfo(CGFunctionInfo &FI) const {
8038   ABIArgInfo &RetInfo = FI.getReturnInfo();
8039   if (!getCXXABI().classifyReturnType(FI))
8040     RetInfo = classifyReturnType(FI.getReturnType());
8041 
8042   // Check if a pointer to an aggregate is passed as a hidden argument.
8043   uint64_t Offset = RetInfo.isIndirect() ? MinABIStackAlignInBytes : 0;
8044 
8045   for (auto &I : FI.arguments())
8046     I.info = classifyArgumentType(I.type, Offset);
8047 }
8048 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType OrigTy) const8049 Address MipsABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
8050                                QualType OrigTy) const {
8051   QualType Ty = OrigTy;
8052 
8053   // Integer arguments are promoted to 32-bit on O32 and 64-bit on N32/N64.
8054   // Pointers are also promoted in the same way but this only matters for N32.
8055   unsigned SlotSizeInBits = IsO32 ? 32 : 64;
8056   unsigned PtrWidth = getTarget().getPointerWidth(0);
8057   bool DidPromote = false;
8058   if ((Ty->isIntegerType() &&
8059           getContext().getIntWidth(Ty) < SlotSizeInBits) ||
8060       (Ty->isPointerType() && PtrWidth < SlotSizeInBits)) {
8061     DidPromote = true;
8062     Ty = getContext().getIntTypeForBitwidth(SlotSizeInBits,
8063                                             Ty->isSignedIntegerType());
8064   }
8065 
8066   auto TyInfo = getContext().getTypeInfoInChars(Ty);
8067 
8068   // The alignment of things in the argument area is never larger than
8069   // StackAlignInBytes.
8070   TyInfo.Align =
8071     std::min(TyInfo.Align, CharUnits::fromQuantity(StackAlignInBytes));
8072 
8073   // MinABIStackAlignInBytes is the size of argument slots on the stack.
8074   CharUnits ArgSlotSize = CharUnits::fromQuantity(MinABIStackAlignInBytes);
8075 
8076   Address Addr = emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*indirect*/ false,
8077                           TyInfo, ArgSlotSize, /*AllowHigherAlign*/ true);
8078 
8079 
8080   // If there was a promotion, "unpromote" into a temporary.
8081   // TODO: can we just use a pointer into a subset of the original slot?
8082   if (DidPromote) {
8083     Address Temp = CGF.CreateMemTemp(OrigTy, "vaarg.promotion-temp");
8084     llvm::Value *Promoted = CGF.Builder.CreateLoad(Addr);
8085 
8086     // Truncate down to the right width.
8087     llvm::Type *IntTy = (OrigTy->isIntegerType() ? Temp.getElementType()
8088                                                  : CGF.IntPtrTy);
8089     llvm::Value *V = CGF.Builder.CreateTrunc(Promoted, IntTy);
8090     if (OrigTy->isPointerType())
8091       V = CGF.Builder.CreateIntToPtr(V, Temp.getElementType());
8092 
8093     CGF.Builder.CreateStore(V, Temp);
8094     Addr = Temp;
8095   }
8096 
8097   return Addr;
8098 }
8099 
extendType(QualType Ty) const8100 ABIArgInfo MipsABIInfo::extendType(QualType Ty) const {
8101   int TySize = getContext().getTypeSize(Ty);
8102 
8103   // MIPS64 ABI requires unsigned 32 bit integers to be sign extended.
8104   if (Ty->isUnsignedIntegerOrEnumerationType() && TySize == 32)
8105     return ABIArgInfo::getSignExtend(Ty);
8106 
8107   return ABIArgInfo::getExtend(Ty);
8108 }
8109 
8110 bool
initDwarfEHRegSizeTable(CodeGen::CodeGenFunction & CGF,llvm::Value * Address) const8111 MIPSTargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
8112                                                llvm::Value *Address) const {
8113   // This information comes from gcc's implementation, which seems to
8114   // as canonical as it gets.
8115 
8116   // Everything on MIPS is 4 bytes.  Double-precision FP registers
8117   // are aliased to pairs of single-precision FP registers.
8118   llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
8119 
8120   // 0-31 are the general purpose registers, $0 - $31.
8121   // 32-63 are the floating-point registers, $f0 - $f31.
8122   // 64 and 65 are the multiply/divide registers, $hi and $lo.
8123   // 66 is the (notional, I think) register for signal-handler return.
8124   AssignToArrayRange(CGF.Builder, Address, Four8, 0, 65);
8125 
8126   // 67-74 are the floating-point status registers, $fcc0 - $fcc7.
8127   // They are one bit wide and ignored here.
8128 
8129   // 80-111 are the coprocessor 0 registers, $c0r0 - $c0r31.
8130   // (coprocessor 1 is the FP unit)
8131   // 112-143 are the coprocessor 2 registers, $c2r0 - $c2r31.
8132   // 144-175 are the coprocessor 3 registers, $c3r0 - $c3r31.
8133   // 176-181 are the DSP accumulator registers.
8134   AssignToArrayRange(CGF.Builder, Address, Four8, 80, 181);
8135   return false;
8136 }
8137 
8138 //===----------------------------------------------------------------------===//
8139 // M68k ABI Implementation
8140 //===----------------------------------------------------------------------===//
8141 
8142 namespace {
8143 
8144 class M68kTargetCodeGenInfo : public TargetCodeGenInfo {
8145 public:
M68kTargetCodeGenInfo(CodeGenTypes & CGT)8146   M68kTargetCodeGenInfo(CodeGenTypes &CGT)
8147       : TargetCodeGenInfo(std::make_unique<DefaultABIInfo>(CGT)) {}
8148   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
8149                            CodeGen::CodeGenModule &M) const override;
8150 };
8151 
8152 } // namespace
8153 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & M) const8154 void M68kTargetCodeGenInfo::setTargetAttributes(
8155     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &M) const {
8156   if (const auto *FD = dyn_cast_or_null<FunctionDecl>(D)) {
8157     if (const auto *attr = FD->getAttr<M68kInterruptAttr>()) {
8158       // Handle 'interrupt' attribute:
8159       llvm::Function *F = cast<llvm::Function>(GV);
8160 
8161       // Step 1: Set ISR calling convention.
8162       F->setCallingConv(llvm::CallingConv::M68k_INTR);
8163 
8164       // Step 2: Add attributes goodness.
8165       F->addFnAttr(llvm::Attribute::NoInline);
8166 
8167       // Step 3: Emit ISR vector alias.
8168       unsigned Num = attr->getNumber() / 2;
8169       llvm::GlobalAlias::create(llvm::Function::ExternalLinkage,
8170                                 "__isr_" + Twine(Num), F);
8171     }
8172   }
8173 }
8174 
8175 //===----------------------------------------------------------------------===//
8176 // AVR ABI Implementation. Documented at
8177 // https://gcc.gnu.org/wiki/avr-gcc#Calling_Convention
8178 // https://gcc.gnu.org/wiki/avr-gcc#Reduced_Tiny
8179 //===----------------------------------------------------------------------===//
8180 
8181 namespace {
8182 class AVRABIInfo : public DefaultABIInfo {
8183 public:
AVRABIInfo(CodeGenTypes & CGT)8184   AVRABIInfo(CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
8185 
classifyReturnType(QualType Ty) const8186   ABIArgInfo classifyReturnType(QualType Ty) const {
8187     // A return struct with size less than or equal to 8 bytes is returned
8188     // directly via registers R18-R25.
8189     if (isAggregateTypeForABI(Ty) && getContext().getTypeSize(Ty) <= 64)
8190       return ABIArgInfo::getDirect();
8191     else
8192       return DefaultABIInfo::classifyReturnType(Ty);
8193   }
8194 
8195   // Just copy the original implementation of DefaultABIInfo::computeInfo(),
8196   // since DefaultABIInfo::classify{Return,Argument}Type() are not virtual.
computeInfo(CGFunctionInfo & FI) const8197   void computeInfo(CGFunctionInfo &FI) const override {
8198     if (!getCXXABI().classifyReturnType(FI))
8199       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
8200     for (auto &I : FI.arguments())
8201       I.info = classifyArgumentType(I.type);
8202   }
8203 };
8204 
8205 class AVRTargetCodeGenInfo : public TargetCodeGenInfo {
8206 public:
AVRTargetCodeGenInfo(CodeGenTypes & CGT)8207   AVRTargetCodeGenInfo(CodeGenTypes &CGT)
8208       : TargetCodeGenInfo(std::make_unique<AVRABIInfo>(CGT)) {}
8209 
getGlobalVarAddressSpace(CodeGenModule & CGM,const VarDecl * D) const8210   LangAS getGlobalVarAddressSpace(CodeGenModule &CGM,
8211                                   const VarDecl *D) const override {
8212     // Check if a global/static variable is defined within address space 1
8213     // but not constant.
8214     LangAS AS = D->getType().getAddressSpace();
8215     if (isTargetAddressSpace(AS) && toTargetAddressSpace(AS) == 1 &&
8216         !D->getType().isConstQualified())
8217       CGM.getDiags().Report(D->getLocation(),
8218                             diag::err_verify_nonconst_addrspace)
8219           << "__flash";
8220     return TargetCodeGenInfo::getGlobalVarAddressSpace(CGM, D);
8221   }
8222 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & CGM) const8223   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
8224                            CodeGen::CodeGenModule &CGM) const override {
8225     if (GV->isDeclaration())
8226       return;
8227     const auto *FD = dyn_cast_or_null<FunctionDecl>(D);
8228     if (!FD) return;
8229     auto *Fn = cast<llvm::Function>(GV);
8230 
8231     if (FD->getAttr<AVRInterruptAttr>())
8232       Fn->addFnAttr("interrupt");
8233 
8234     if (FD->getAttr<AVRSignalAttr>())
8235       Fn->addFnAttr("signal");
8236   }
8237 };
8238 }
8239 
8240 //===----------------------------------------------------------------------===//
8241 // TCE ABI Implementation (see http://tce.cs.tut.fi). Uses mostly the defaults.
8242 // Currently subclassed only to implement custom OpenCL C function attribute
8243 // handling.
8244 //===----------------------------------------------------------------------===//
8245 
8246 namespace {
8247 
8248 class TCETargetCodeGenInfo : public DefaultTargetCodeGenInfo {
8249 public:
TCETargetCodeGenInfo(CodeGenTypes & CGT)8250   TCETargetCodeGenInfo(CodeGenTypes &CGT)
8251     : DefaultTargetCodeGenInfo(CGT) {}
8252 
8253   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
8254                            CodeGen::CodeGenModule &M) const override;
8255 };
8256 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & M) const8257 void TCETargetCodeGenInfo::setTargetAttributes(
8258     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &M) const {
8259   if (GV->isDeclaration())
8260     return;
8261   const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
8262   if (!FD) return;
8263 
8264   llvm::Function *F = cast<llvm::Function>(GV);
8265 
8266   if (M.getLangOpts().OpenCL) {
8267     if (FD->hasAttr<OpenCLKernelAttr>()) {
8268       // OpenCL C Kernel functions are not subject to inlining
8269       F->addFnAttr(llvm::Attribute::NoInline);
8270       const ReqdWorkGroupSizeAttr *Attr = FD->getAttr<ReqdWorkGroupSizeAttr>();
8271       if (Attr) {
8272         // Convert the reqd_work_group_size() attributes to metadata.
8273         llvm::LLVMContext &Context = F->getContext();
8274         llvm::NamedMDNode *OpenCLMetadata =
8275             M.getModule().getOrInsertNamedMetadata(
8276                 "opencl.kernel_wg_size_info");
8277 
8278         SmallVector<llvm::Metadata *, 5> Operands;
8279         Operands.push_back(llvm::ConstantAsMetadata::get(F));
8280 
8281         Operands.push_back(
8282             llvm::ConstantAsMetadata::get(llvm::Constant::getIntegerValue(
8283                 M.Int32Ty, llvm::APInt(32, Attr->getXDim()))));
8284         Operands.push_back(
8285             llvm::ConstantAsMetadata::get(llvm::Constant::getIntegerValue(
8286                 M.Int32Ty, llvm::APInt(32, Attr->getYDim()))));
8287         Operands.push_back(
8288             llvm::ConstantAsMetadata::get(llvm::Constant::getIntegerValue(
8289                 M.Int32Ty, llvm::APInt(32, Attr->getZDim()))));
8290 
8291         // Add a boolean constant operand for "required" (true) or "hint"
8292         // (false) for implementing the work_group_size_hint attr later.
8293         // Currently always true as the hint is not yet implemented.
8294         Operands.push_back(
8295             llvm::ConstantAsMetadata::get(llvm::ConstantInt::getTrue(Context)));
8296         OpenCLMetadata->addOperand(llvm::MDNode::get(Context, Operands));
8297       }
8298     }
8299   }
8300 }
8301 
8302 }
8303 
8304 //===----------------------------------------------------------------------===//
8305 // Hexagon ABI Implementation
8306 //===----------------------------------------------------------------------===//
8307 
8308 namespace {
8309 
8310 class HexagonABIInfo : public DefaultABIInfo {
8311 public:
HexagonABIInfo(CodeGenTypes & CGT)8312   HexagonABIInfo(CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
8313 
8314 private:
8315   ABIArgInfo classifyReturnType(QualType RetTy) const;
8316   ABIArgInfo classifyArgumentType(QualType RetTy) const;
8317   ABIArgInfo classifyArgumentType(QualType RetTy, unsigned *RegsLeft) const;
8318 
8319   void computeInfo(CGFunctionInfo &FI) const override;
8320 
8321   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
8322                     QualType Ty) const override;
8323   Address EmitVAArgFromMemory(CodeGenFunction &CFG, Address VAListAddr,
8324                               QualType Ty) const;
8325   Address EmitVAArgForHexagon(CodeGenFunction &CFG, Address VAListAddr,
8326                               QualType Ty) const;
8327   Address EmitVAArgForHexagonLinux(CodeGenFunction &CFG, Address VAListAddr,
8328                                    QualType Ty) const;
8329 };
8330 
8331 class HexagonTargetCodeGenInfo : public TargetCodeGenInfo {
8332 public:
HexagonTargetCodeGenInfo(CodeGenTypes & CGT)8333   HexagonTargetCodeGenInfo(CodeGenTypes &CGT)
8334       : TargetCodeGenInfo(std::make_unique<HexagonABIInfo>(CGT)) {}
8335 
getDwarfEHStackPointer(CodeGen::CodeGenModule & M) const8336   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
8337     return 29;
8338   }
8339 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & GCM) const8340   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
8341                            CodeGen::CodeGenModule &GCM) const override {
8342     if (GV->isDeclaration())
8343       return;
8344     const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
8345     if (!FD)
8346       return;
8347   }
8348 };
8349 
8350 } // namespace
8351 
computeInfo(CGFunctionInfo & FI) const8352 void HexagonABIInfo::computeInfo(CGFunctionInfo &FI) const {
8353   unsigned RegsLeft = 6;
8354   if (!getCXXABI().classifyReturnType(FI))
8355     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
8356   for (auto &I : FI.arguments())
8357     I.info = classifyArgumentType(I.type, &RegsLeft);
8358 }
8359 
HexagonAdjustRegsLeft(uint64_t Size,unsigned * RegsLeft)8360 static bool HexagonAdjustRegsLeft(uint64_t Size, unsigned *RegsLeft) {
8361   assert(Size <= 64 && "Not expecting to pass arguments larger than 64 bits"
8362                        " through registers");
8363 
8364   if (*RegsLeft == 0)
8365     return false;
8366 
8367   if (Size <= 32) {
8368     (*RegsLeft)--;
8369     return true;
8370   }
8371 
8372   if (2 <= (*RegsLeft & (~1U))) {
8373     *RegsLeft = (*RegsLeft & (~1U)) - 2;
8374     return true;
8375   }
8376 
8377   // Next available register was r5 but candidate was greater than 32-bits so it
8378   // has to go on the stack. However we still consume r5
8379   if (*RegsLeft == 1)
8380     *RegsLeft = 0;
8381 
8382   return false;
8383 }
8384 
classifyArgumentType(QualType Ty,unsigned * RegsLeft) const8385 ABIArgInfo HexagonABIInfo::classifyArgumentType(QualType Ty,
8386                                                 unsigned *RegsLeft) const {
8387   if (!isAggregateTypeForABI(Ty)) {
8388     // Treat an enum type as its underlying type.
8389     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
8390       Ty = EnumTy->getDecl()->getIntegerType();
8391 
8392     uint64_t Size = getContext().getTypeSize(Ty);
8393     if (Size <= 64)
8394       HexagonAdjustRegsLeft(Size, RegsLeft);
8395 
8396     if (Size > 64 && Ty->isExtIntType())
8397       return getNaturalAlignIndirect(Ty, /*ByVal=*/true);
8398 
8399     return isPromotableIntegerTypeForABI(Ty) ? ABIArgInfo::getExtend(Ty)
8400                                              : ABIArgInfo::getDirect();
8401   }
8402 
8403   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
8404     return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
8405 
8406   // Ignore empty records.
8407   if (isEmptyRecord(getContext(), Ty, true))
8408     return ABIArgInfo::getIgnore();
8409 
8410   uint64_t Size = getContext().getTypeSize(Ty);
8411   unsigned Align = getContext().getTypeAlign(Ty);
8412 
8413   if (Size > 64)
8414     return getNaturalAlignIndirect(Ty, /*ByVal=*/true);
8415 
8416   if (HexagonAdjustRegsLeft(Size, RegsLeft))
8417     Align = Size <= 32 ? 32 : 64;
8418   if (Size <= Align) {
8419     // Pass in the smallest viable integer type.
8420     if (!llvm::isPowerOf2_64(Size))
8421       Size = llvm::NextPowerOf2(Size);
8422     return ABIArgInfo::getDirect(llvm::Type::getIntNTy(getVMContext(), Size));
8423   }
8424   return DefaultABIInfo::classifyArgumentType(Ty);
8425 }
8426 
classifyReturnType(QualType RetTy) const8427 ABIArgInfo HexagonABIInfo::classifyReturnType(QualType RetTy) const {
8428   if (RetTy->isVoidType())
8429     return ABIArgInfo::getIgnore();
8430 
8431   const TargetInfo &T = CGT.getTarget();
8432   uint64_t Size = getContext().getTypeSize(RetTy);
8433 
8434   if (RetTy->getAs<VectorType>()) {
8435     // HVX vectors are returned in vector registers or register pairs.
8436     if (T.hasFeature("hvx")) {
8437       assert(T.hasFeature("hvx-length64b") || T.hasFeature("hvx-length128b"));
8438       uint64_t VecSize = T.hasFeature("hvx-length64b") ? 64*8 : 128*8;
8439       if (Size == VecSize || Size == 2*VecSize)
8440         return ABIArgInfo::getDirectInReg();
8441     }
8442     // Large vector types should be returned via memory.
8443     if (Size > 64)
8444       return getNaturalAlignIndirect(RetTy);
8445   }
8446 
8447   if (!isAggregateTypeForABI(RetTy)) {
8448     // Treat an enum type as its underlying type.
8449     if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
8450       RetTy = EnumTy->getDecl()->getIntegerType();
8451 
8452     if (Size > 64 && RetTy->isExtIntType())
8453       return getNaturalAlignIndirect(RetTy, /*ByVal=*/false);
8454 
8455     return isPromotableIntegerTypeForABI(RetTy) ? ABIArgInfo::getExtend(RetTy)
8456                                                 : ABIArgInfo::getDirect();
8457   }
8458 
8459   if (isEmptyRecord(getContext(), RetTy, true))
8460     return ABIArgInfo::getIgnore();
8461 
8462   // Aggregates <= 8 bytes are returned in registers, other aggregates
8463   // are returned indirectly.
8464   if (Size <= 64) {
8465     // Return in the smallest viable integer type.
8466     if (!llvm::isPowerOf2_64(Size))
8467       Size = llvm::NextPowerOf2(Size);
8468     return ABIArgInfo::getDirect(llvm::Type::getIntNTy(getVMContext(), Size));
8469   }
8470   return getNaturalAlignIndirect(RetTy, /*ByVal=*/true);
8471 }
8472 
EmitVAArgFromMemory(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const8473 Address HexagonABIInfo::EmitVAArgFromMemory(CodeGenFunction &CGF,
8474                                             Address VAListAddr,
8475                                             QualType Ty) const {
8476   // Load the overflow area pointer.
8477   Address __overflow_area_pointer_p =
8478       CGF.Builder.CreateStructGEP(VAListAddr, 2, "__overflow_area_pointer_p");
8479   llvm::Value *__overflow_area_pointer = CGF.Builder.CreateLoad(
8480       __overflow_area_pointer_p, "__overflow_area_pointer");
8481 
8482   uint64_t Align = CGF.getContext().getTypeAlign(Ty) / 8;
8483   if (Align > 4) {
8484     // Alignment should be a power of 2.
8485     assert((Align & (Align - 1)) == 0 && "Alignment is not power of 2!");
8486 
8487     // overflow_arg_area = (overflow_arg_area + align - 1) & -align;
8488     llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int64Ty, Align - 1);
8489 
8490     // Add offset to the current pointer to access the argument.
8491     __overflow_area_pointer =
8492         CGF.Builder.CreateGEP(CGF.Int8Ty, __overflow_area_pointer, Offset);
8493     llvm::Value *AsInt =
8494         CGF.Builder.CreatePtrToInt(__overflow_area_pointer, CGF.Int32Ty);
8495 
8496     // Create a mask which should be "AND"ed
8497     // with (overflow_arg_area + align - 1)
8498     llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int32Ty, -(int)Align);
8499     __overflow_area_pointer = CGF.Builder.CreateIntToPtr(
8500         CGF.Builder.CreateAnd(AsInt, Mask), __overflow_area_pointer->getType(),
8501         "__overflow_area_pointer.align");
8502   }
8503 
8504   // Get the type of the argument from memory and bitcast
8505   // overflow area pointer to the argument type.
8506   llvm::Type *PTy = CGF.ConvertTypeForMem(Ty);
8507   Address AddrTyped = CGF.Builder.CreateBitCast(
8508       Address(__overflow_area_pointer, CharUnits::fromQuantity(Align)),
8509       llvm::PointerType::getUnqual(PTy));
8510 
8511   // Round up to the minimum stack alignment for varargs which is 4 bytes.
8512   uint64_t Offset = llvm::alignTo(CGF.getContext().getTypeSize(Ty) / 8, 4);
8513 
8514   __overflow_area_pointer = CGF.Builder.CreateGEP(
8515       CGF.Int8Ty, __overflow_area_pointer,
8516       llvm::ConstantInt::get(CGF.Int32Ty, Offset),
8517       "__overflow_area_pointer.next");
8518   CGF.Builder.CreateStore(__overflow_area_pointer, __overflow_area_pointer_p);
8519 
8520   return AddrTyped;
8521 }
8522 
EmitVAArgForHexagon(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const8523 Address HexagonABIInfo::EmitVAArgForHexagon(CodeGenFunction &CGF,
8524                                             Address VAListAddr,
8525                                             QualType Ty) const {
8526   // FIXME: Need to handle alignment
8527   llvm::Type *BP = CGF.Int8PtrTy;
8528   llvm::Type *BPP = CGF.Int8PtrPtrTy;
8529   CGBuilderTy &Builder = CGF.Builder;
8530   Address VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
8531   llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
8532   // Handle address alignment for type alignment > 32 bits
8533   uint64_t TyAlign = CGF.getContext().getTypeAlign(Ty) / 8;
8534   if (TyAlign > 4) {
8535     assert((TyAlign & (TyAlign - 1)) == 0 && "Alignment is not power of 2!");
8536     llvm::Value *AddrAsInt = Builder.CreatePtrToInt(Addr, CGF.Int32Ty);
8537     AddrAsInt = Builder.CreateAdd(AddrAsInt, Builder.getInt32(TyAlign - 1));
8538     AddrAsInt = Builder.CreateAnd(AddrAsInt, Builder.getInt32(~(TyAlign - 1)));
8539     Addr = Builder.CreateIntToPtr(AddrAsInt, BP);
8540   }
8541   llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
8542   Address AddrTyped = Builder.CreateBitCast(
8543       Address(Addr, CharUnits::fromQuantity(TyAlign)), PTy);
8544 
8545   uint64_t Offset = llvm::alignTo(CGF.getContext().getTypeSize(Ty) / 8, 4);
8546   llvm::Value *NextAddr = Builder.CreateGEP(
8547       CGF.Int8Ty, Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset), "ap.next");
8548   Builder.CreateStore(NextAddr, VAListAddrAsBPP);
8549 
8550   return AddrTyped;
8551 }
8552 
EmitVAArgForHexagonLinux(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const8553 Address HexagonABIInfo::EmitVAArgForHexagonLinux(CodeGenFunction &CGF,
8554                                                  Address VAListAddr,
8555                                                  QualType Ty) const {
8556   int ArgSize = CGF.getContext().getTypeSize(Ty) / 8;
8557 
8558   if (ArgSize > 8)
8559     return EmitVAArgFromMemory(CGF, VAListAddr, Ty);
8560 
8561   // Here we have check if the argument is in register area or
8562   // in overflow area.
8563   // If the saved register area pointer + argsize rounded up to alignment >
8564   // saved register area end pointer, argument is in overflow area.
8565   unsigned RegsLeft = 6;
8566   Ty = CGF.getContext().getCanonicalType(Ty);
8567   (void)classifyArgumentType(Ty, &RegsLeft);
8568 
8569   llvm::BasicBlock *MaybeRegBlock = CGF.createBasicBlock("vaarg.maybe_reg");
8570   llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
8571   llvm::BasicBlock *OnStackBlock = CGF.createBasicBlock("vaarg.on_stack");
8572   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
8573 
8574   // Get rounded size of the argument.GCC does not allow vararg of
8575   // size < 4 bytes. We follow the same logic here.
8576   ArgSize = (CGF.getContext().getTypeSize(Ty) <= 32) ? 4 : 8;
8577   int ArgAlign = (CGF.getContext().getTypeSize(Ty) <= 32) ? 4 : 8;
8578 
8579   // Argument may be in saved register area
8580   CGF.EmitBlock(MaybeRegBlock);
8581 
8582   // Load the current saved register area pointer.
8583   Address __current_saved_reg_area_pointer_p = CGF.Builder.CreateStructGEP(
8584       VAListAddr, 0, "__current_saved_reg_area_pointer_p");
8585   llvm::Value *__current_saved_reg_area_pointer = CGF.Builder.CreateLoad(
8586       __current_saved_reg_area_pointer_p, "__current_saved_reg_area_pointer");
8587 
8588   // Load the saved register area end pointer.
8589   Address __saved_reg_area_end_pointer_p = CGF.Builder.CreateStructGEP(
8590       VAListAddr, 1, "__saved_reg_area_end_pointer_p");
8591   llvm::Value *__saved_reg_area_end_pointer = CGF.Builder.CreateLoad(
8592       __saved_reg_area_end_pointer_p, "__saved_reg_area_end_pointer");
8593 
8594   // If the size of argument is > 4 bytes, check if the stack
8595   // location is aligned to 8 bytes
8596   if (ArgAlign > 4) {
8597 
8598     llvm::Value *__current_saved_reg_area_pointer_int =
8599         CGF.Builder.CreatePtrToInt(__current_saved_reg_area_pointer,
8600                                    CGF.Int32Ty);
8601 
8602     __current_saved_reg_area_pointer_int = CGF.Builder.CreateAdd(
8603         __current_saved_reg_area_pointer_int,
8604         llvm::ConstantInt::get(CGF.Int32Ty, (ArgAlign - 1)),
8605         "align_current_saved_reg_area_pointer");
8606 
8607     __current_saved_reg_area_pointer_int =
8608         CGF.Builder.CreateAnd(__current_saved_reg_area_pointer_int,
8609                               llvm::ConstantInt::get(CGF.Int32Ty, -ArgAlign),
8610                               "align_current_saved_reg_area_pointer");
8611 
8612     __current_saved_reg_area_pointer =
8613         CGF.Builder.CreateIntToPtr(__current_saved_reg_area_pointer_int,
8614                                    __current_saved_reg_area_pointer->getType(),
8615                                    "align_current_saved_reg_area_pointer");
8616   }
8617 
8618   llvm::Value *__new_saved_reg_area_pointer =
8619       CGF.Builder.CreateGEP(CGF.Int8Ty, __current_saved_reg_area_pointer,
8620                             llvm::ConstantInt::get(CGF.Int32Ty, ArgSize),
8621                             "__new_saved_reg_area_pointer");
8622 
8623   llvm::Value *UsingStack = 0;
8624   UsingStack = CGF.Builder.CreateICmpSGT(__new_saved_reg_area_pointer,
8625                                          __saved_reg_area_end_pointer);
8626 
8627   CGF.Builder.CreateCondBr(UsingStack, OnStackBlock, InRegBlock);
8628 
8629   // Argument in saved register area
8630   // Implement the block where argument is in register saved area
8631   CGF.EmitBlock(InRegBlock);
8632 
8633   llvm::Type *PTy = CGF.ConvertType(Ty);
8634   llvm::Value *__saved_reg_area_p = CGF.Builder.CreateBitCast(
8635       __current_saved_reg_area_pointer, llvm::PointerType::getUnqual(PTy));
8636 
8637   CGF.Builder.CreateStore(__new_saved_reg_area_pointer,
8638                           __current_saved_reg_area_pointer_p);
8639 
8640   CGF.EmitBranch(ContBlock);
8641 
8642   // Argument in overflow area
8643   // Implement the block where the argument is in overflow area.
8644   CGF.EmitBlock(OnStackBlock);
8645 
8646   // Load the overflow area pointer
8647   Address __overflow_area_pointer_p =
8648       CGF.Builder.CreateStructGEP(VAListAddr, 2, "__overflow_area_pointer_p");
8649   llvm::Value *__overflow_area_pointer = CGF.Builder.CreateLoad(
8650       __overflow_area_pointer_p, "__overflow_area_pointer");
8651 
8652   // Align the overflow area pointer according to the alignment of the argument
8653   if (ArgAlign > 4) {
8654     llvm::Value *__overflow_area_pointer_int =
8655         CGF.Builder.CreatePtrToInt(__overflow_area_pointer, CGF.Int32Ty);
8656 
8657     __overflow_area_pointer_int =
8658         CGF.Builder.CreateAdd(__overflow_area_pointer_int,
8659                               llvm::ConstantInt::get(CGF.Int32Ty, ArgAlign - 1),
8660                               "align_overflow_area_pointer");
8661 
8662     __overflow_area_pointer_int =
8663         CGF.Builder.CreateAnd(__overflow_area_pointer_int,
8664                               llvm::ConstantInt::get(CGF.Int32Ty, -ArgAlign),
8665                               "align_overflow_area_pointer");
8666 
8667     __overflow_area_pointer = CGF.Builder.CreateIntToPtr(
8668         __overflow_area_pointer_int, __overflow_area_pointer->getType(),
8669         "align_overflow_area_pointer");
8670   }
8671 
8672   // Get the pointer for next argument in overflow area and store it
8673   // to overflow area pointer.
8674   llvm::Value *__new_overflow_area_pointer = CGF.Builder.CreateGEP(
8675       CGF.Int8Ty, __overflow_area_pointer,
8676       llvm::ConstantInt::get(CGF.Int32Ty, ArgSize),
8677       "__overflow_area_pointer.next");
8678 
8679   CGF.Builder.CreateStore(__new_overflow_area_pointer,
8680                           __overflow_area_pointer_p);
8681 
8682   CGF.Builder.CreateStore(__new_overflow_area_pointer,
8683                           __current_saved_reg_area_pointer_p);
8684 
8685   // Bitcast the overflow area pointer to the type of argument.
8686   llvm::Type *OverflowPTy = CGF.ConvertTypeForMem(Ty);
8687   llvm::Value *__overflow_area_p = CGF.Builder.CreateBitCast(
8688       __overflow_area_pointer, llvm::PointerType::getUnqual(OverflowPTy));
8689 
8690   CGF.EmitBranch(ContBlock);
8691 
8692   // Get the correct pointer to load the variable argument
8693   // Implement the ContBlock
8694   CGF.EmitBlock(ContBlock);
8695 
8696   llvm::Type *MemPTy = llvm::PointerType::getUnqual(CGF.ConvertTypeForMem(Ty));
8697   llvm::PHINode *ArgAddr = CGF.Builder.CreatePHI(MemPTy, 2, "vaarg.addr");
8698   ArgAddr->addIncoming(__saved_reg_area_p, InRegBlock);
8699   ArgAddr->addIncoming(__overflow_area_p, OnStackBlock);
8700 
8701   return Address(ArgAddr, CharUnits::fromQuantity(ArgAlign));
8702 }
8703 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const8704 Address HexagonABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
8705                                   QualType Ty) const {
8706 
8707   if (getTarget().getTriple().isMusl())
8708     return EmitVAArgForHexagonLinux(CGF, VAListAddr, Ty);
8709 
8710   return EmitVAArgForHexagon(CGF, VAListAddr, Ty);
8711 }
8712 
8713 //===----------------------------------------------------------------------===//
8714 // Lanai ABI Implementation
8715 //===----------------------------------------------------------------------===//
8716 
8717 namespace {
8718 class LanaiABIInfo : public DefaultABIInfo {
8719 public:
LanaiABIInfo(CodeGen::CodeGenTypes & CGT)8720   LanaiABIInfo(CodeGen::CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
8721 
8722   bool shouldUseInReg(QualType Ty, CCState &State) const;
8723 
computeInfo(CGFunctionInfo & FI) const8724   void computeInfo(CGFunctionInfo &FI) const override {
8725     CCState State(FI);
8726     // Lanai uses 4 registers to pass arguments unless the function has the
8727     // regparm attribute set.
8728     if (FI.getHasRegParm()) {
8729       State.FreeRegs = FI.getRegParm();
8730     } else {
8731       State.FreeRegs = 4;
8732     }
8733 
8734     if (!getCXXABI().classifyReturnType(FI))
8735       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
8736     for (auto &I : FI.arguments())
8737       I.info = classifyArgumentType(I.type, State);
8738   }
8739 
8740   ABIArgInfo getIndirectResult(QualType Ty, bool ByVal, CCState &State) const;
8741   ABIArgInfo classifyArgumentType(QualType RetTy, CCState &State) const;
8742 };
8743 } // end anonymous namespace
8744 
shouldUseInReg(QualType Ty,CCState & State) const8745 bool LanaiABIInfo::shouldUseInReg(QualType Ty, CCState &State) const {
8746   unsigned Size = getContext().getTypeSize(Ty);
8747   unsigned SizeInRegs = llvm::alignTo(Size, 32U) / 32U;
8748 
8749   if (SizeInRegs == 0)
8750     return false;
8751 
8752   if (SizeInRegs > State.FreeRegs) {
8753     State.FreeRegs = 0;
8754     return false;
8755   }
8756 
8757   State.FreeRegs -= SizeInRegs;
8758 
8759   return true;
8760 }
8761 
getIndirectResult(QualType Ty,bool ByVal,CCState & State) const8762 ABIArgInfo LanaiABIInfo::getIndirectResult(QualType Ty, bool ByVal,
8763                                            CCState &State) const {
8764   if (!ByVal) {
8765     if (State.FreeRegs) {
8766       --State.FreeRegs; // Non-byval indirects just use one pointer.
8767       return getNaturalAlignIndirectInReg(Ty);
8768     }
8769     return getNaturalAlignIndirect(Ty, false);
8770   }
8771 
8772   // Compute the byval alignment.
8773   const unsigned MinABIStackAlignInBytes = 4;
8774   unsigned TypeAlign = getContext().getTypeAlign(Ty) / 8;
8775   return ABIArgInfo::getIndirect(CharUnits::fromQuantity(4), /*ByVal=*/true,
8776                                  /*Realign=*/TypeAlign >
8777                                      MinABIStackAlignInBytes);
8778 }
8779 
classifyArgumentType(QualType Ty,CCState & State) const8780 ABIArgInfo LanaiABIInfo::classifyArgumentType(QualType Ty,
8781                                               CCState &State) const {
8782   // Check with the C++ ABI first.
8783   const RecordType *RT = Ty->getAs<RecordType>();
8784   if (RT) {
8785     CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, getCXXABI());
8786     if (RAA == CGCXXABI::RAA_Indirect) {
8787       return getIndirectResult(Ty, /*ByVal=*/false, State);
8788     } else if (RAA == CGCXXABI::RAA_DirectInMemory) {
8789       return getNaturalAlignIndirect(Ty, /*ByVal=*/true);
8790     }
8791   }
8792 
8793   if (isAggregateTypeForABI(Ty)) {
8794     // Structures with flexible arrays are always indirect.
8795     if (RT && RT->getDecl()->hasFlexibleArrayMember())
8796       return getIndirectResult(Ty, /*ByVal=*/true, State);
8797 
8798     // Ignore empty structs/unions.
8799     if (isEmptyRecord(getContext(), Ty, true))
8800       return ABIArgInfo::getIgnore();
8801 
8802     llvm::LLVMContext &LLVMContext = getVMContext();
8803     unsigned SizeInRegs = (getContext().getTypeSize(Ty) + 31) / 32;
8804     if (SizeInRegs <= State.FreeRegs) {
8805       llvm::IntegerType *Int32 = llvm::Type::getInt32Ty(LLVMContext);
8806       SmallVector<llvm::Type *, 3> Elements(SizeInRegs, Int32);
8807       llvm::Type *Result = llvm::StructType::get(LLVMContext, Elements);
8808       State.FreeRegs -= SizeInRegs;
8809       return ABIArgInfo::getDirectInReg(Result);
8810     } else {
8811       State.FreeRegs = 0;
8812     }
8813     return getIndirectResult(Ty, true, State);
8814   }
8815 
8816   // Treat an enum type as its underlying type.
8817   if (const auto *EnumTy = Ty->getAs<EnumType>())
8818     Ty = EnumTy->getDecl()->getIntegerType();
8819 
8820   bool InReg = shouldUseInReg(Ty, State);
8821 
8822   // Don't pass >64 bit integers in registers.
8823   if (const auto *EIT = Ty->getAs<ExtIntType>())
8824     if (EIT->getNumBits() > 64)
8825       return getIndirectResult(Ty, /*ByVal=*/true, State);
8826 
8827   if (isPromotableIntegerTypeForABI(Ty)) {
8828     if (InReg)
8829       return ABIArgInfo::getDirectInReg();
8830     return ABIArgInfo::getExtend(Ty);
8831   }
8832   if (InReg)
8833     return ABIArgInfo::getDirectInReg();
8834   return ABIArgInfo::getDirect();
8835 }
8836 
8837 namespace {
8838 class LanaiTargetCodeGenInfo : public TargetCodeGenInfo {
8839 public:
LanaiTargetCodeGenInfo(CodeGen::CodeGenTypes & CGT)8840   LanaiTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
8841       : TargetCodeGenInfo(std::make_unique<LanaiABIInfo>(CGT)) {}
8842 };
8843 }
8844 
8845 //===----------------------------------------------------------------------===//
8846 // AMDGPU ABI Implementation
8847 //===----------------------------------------------------------------------===//
8848 
8849 namespace {
8850 
8851 class AMDGPUABIInfo final : public DefaultABIInfo {
8852 private:
8853   static const unsigned MaxNumRegsForArgsRet = 16;
8854 
8855   unsigned numRegsForType(QualType Ty) const;
8856 
8857   bool isHomogeneousAggregateBaseType(QualType Ty) const override;
8858   bool isHomogeneousAggregateSmallEnough(const Type *Base,
8859                                          uint64_t Members) const override;
8860 
8861   // Coerce HIP scalar pointer arguments from generic pointers to global ones.
coerceKernelArgumentType(llvm::Type * Ty,unsigned FromAS,unsigned ToAS) const8862   llvm::Type *coerceKernelArgumentType(llvm::Type *Ty, unsigned FromAS,
8863                                        unsigned ToAS) const {
8864     // Single value types.
8865     if (Ty->isPointerTy() && Ty->getPointerAddressSpace() == FromAS)
8866       return llvm::PointerType::get(
8867           cast<llvm::PointerType>(Ty)->getElementType(), ToAS);
8868     return Ty;
8869   }
8870 
8871 public:
AMDGPUABIInfo(CodeGen::CodeGenTypes & CGT)8872   explicit AMDGPUABIInfo(CodeGen::CodeGenTypes &CGT) :
8873     DefaultABIInfo(CGT) {}
8874 
8875   ABIArgInfo classifyReturnType(QualType RetTy) const;
8876   ABIArgInfo classifyKernelArgumentType(QualType Ty) const;
8877   ABIArgInfo classifyArgumentType(QualType Ty, unsigned &NumRegsLeft) const;
8878 
8879   void computeInfo(CGFunctionInfo &FI) const override;
8880   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
8881                     QualType Ty) const override;
8882 };
8883 
isHomogeneousAggregateBaseType(QualType Ty) const8884 bool AMDGPUABIInfo::isHomogeneousAggregateBaseType(QualType Ty) const {
8885   return true;
8886 }
8887 
isHomogeneousAggregateSmallEnough(const Type * Base,uint64_t Members) const8888 bool AMDGPUABIInfo::isHomogeneousAggregateSmallEnough(
8889   const Type *Base, uint64_t Members) const {
8890   uint32_t NumRegs = (getContext().getTypeSize(Base) + 31) / 32;
8891 
8892   // Homogeneous Aggregates may occupy at most 16 registers.
8893   return Members * NumRegs <= MaxNumRegsForArgsRet;
8894 }
8895 
8896 /// Estimate number of registers the type will use when passed in registers.
numRegsForType(QualType Ty) const8897 unsigned AMDGPUABIInfo::numRegsForType(QualType Ty) const {
8898   unsigned NumRegs = 0;
8899 
8900   if (const VectorType *VT = Ty->getAs<VectorType>()) {
8901     // Compute from the number of elements. The reported size is based on the
8902     // in-memory size, which includes the padding 4th element for 3-vectors.
8903     QualType EltTy = VT->getElementType();
8904     unsigned EltSize = getContext().getTypeSize(EltTy);
8905 
8906     // 16-bit element vectors should be passed as packed.
8907     if (EltSize == 16)
8908       return (VT->getNumElements() + 1) / 2;
8909 
8910     unsigned EltNumRegs = (EltSize + 31) / 32;
8911     return EltNumRegs * VT->getNumElements();
8912   }
8913 
8914   if (const RecordType *RT = Ty->getAs<RecordType>()) {
8915     const RecordDecl *RD = RT->getDecl();
8916     assert(!RD->hasFlexibleArrayMember());
8917 
8918     for (const FieldDecl *Field : RD->fields()) {
8919       QualType FieldTy = Field->getType();
8920       NumRegs += numRegsForType(FieldTy);
8921     }
8922 
8923     return NumRegs;
8924   }
8925 
8926   return (getContext().getTypeSize(Ty) + 31) / 32;
8927 }
8928 
computeInfo(CGFunctionInfo & FI) const8929 void AMDGPUABIInfo::computeInfo(CGFunctionInfo &FI) const {
8930   llvm::CallingConv::ID CC = FI.getCallingConvention();
8931 
8932   if (!getCXXABI().classifyReturnType(FI))
8933     FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
8934 
8935   unsigned NumRegsLeft = MaxNumRegsForArgsRet;
8936   for (auto &Arg : FI.arguments()) {
8937     if (CC == llvm::CallingConv::AMDGPU_KERNEL) {
8938       Arg.info = classifyKernelArgumentType(Arg.type);
8939     } else {
8940       Arg.info = classifyArgumentType(Arg.type, NumRegsLeft);
8941     }
8942   }
8943 }
8944 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const8945 Address AMDGPUABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
8946                                  QualType Ty) const {
8947   llvm_unreachable("AMDGPU does not support varargs");
8948 }
8949 
classifyReturnType(QualType RetTy) const8950 ABIArgInfo AMDGPUABIInfo::classifyReturnType(QualType RetTy) const {
8951   if (isAggregateTypeForABI(RetTy)) {
8952     // Records with non-trivial destructors/copy-constructors should not be
8953     // returned by value.
8954     if (!getRecordArgABI(RetTy, getCXXABI())) {
8955       // Ignore empty structs/unions.
8956       if (isEmptyRecord(getContext(), RetTy, true))
8957         return ABIArgInfo::getIgnore();
8958 
8959       // Lower single-element structs to just return a regular value.
8960       if (const Type *SeltTy = isSingleElementStruct(RetTy, getContext()))
8961         return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
8962 
8963       if (const RecordType *RT = RetTy->getAs<RecordType>()) {
8964         const RecordDecl *RD = RT->getDecl();
8965         if (RD->hasFlexibleArrayMember())
8966           return DefaultABIInfo::classifyReturnType(RetTy);
8967       }
8968 
8969       // Pack aggregates <= 4 bytes into single VGPR or pair.
8970       uint64_t Size = getContext().getTypeSize(RetTy);
8971       if (Size <= 16)
8972         return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
8973 
8974       if (Size <= 32)
8975         return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
8976 
8977       if (Size <= 64) {
8978         llvm::Type *I32Ty = llvm::Type::getInt32Ty(getVMContext());
8979         return ABIArgInfo::getDirect(llvm::ArrayType::get(I32Ty, 2));
8980       }
8981 
8982       if (numRegsForType(RetTy) <= MaxNumRegsForArgsRet)
8983         return ABIArgInfo::getDirect();
8984     }
8985   }
8986 
8987   // Otherwise just do the default thing.
8988   return DefaultABIInfo::classifyReturnType(RetTy);
8989 }
8990 
8991 /// For kernels all parameters are really passed in a special buffer. It doesn't
8992 /// make sense to pass anything byval, so everything must be direct.
classifyKernelArgumentType(QualType Ty) const8993 ABIArgInfo AMDGPUABIInfo::classifyKernelArgumentType(QualType Ty) const {
8994   Ty = useFirstFieldIfTransparentUnion(Ty);
8995 
8996   // TODO: Can we omit empty structs?
8997 
8998   if (const Type *SeltTy = isSingleElementStruct(Ty, getContext()))
8999     Ty = QualType(SeltTy, 0);
9000 
9001   llvm::Type *OrigLTy = CGT.ConvertType(Ty);
9002   llvm::Type *LTy = OrigLTy;
9003   if (getContext().getLangOpts().HIP) {
9004     LTy = coerceKernelArgumentType(
9005         OrigLTy, /*FromAS=*/getContext().getTargetAddressSpace(LangAS::Default),
9006         /*ToAS=*/getContext().getTargetAddressSpace(LangAS::cuda_device));
9007   }
9008 
9009   // FIXME: Should also use this for OpenCL, but it requires addressing the
9010   // problem of kernels being called.
9011   //
9012   // FIXME: This doesn't apply the optimization of coercing pointers in structs
9013   // to global address space when using byref. This would require implementing a
9014   // new kind of coercion of the in-memory type when for indirect arguments.
9015   if (!getContext().getLangOpts().OpenCL && LTy == OrigLTy &&
9016       isAggregateTypeForABI(Ty)) {
9017     return ABIArgInfo::getIndirectAliased(
9018         getContext().getTypeAlignInChars(Ty),
9019         getContext().getTargetAddressSpace(LangAS::opencl_constant),
9020         false /*Realign*/, nullptr /*Padding*/);
9021   }
9022 
9023   // If we set CanBeFlattened to true, CodeGen will expand the struct to its
9024   // individual elements, which confuses the Clover OpenCL backend; therefore we
9025   // have to set it to false here. Other args of getDirect() are just defaults.
9026   return ABIArgInfo::getDirect(LTy, 0, nullptr, false);
9027 }
9028 
classifyArgumentType(QualType Ty,unsigned & NumRegsLeft) const9029 ABIArgInfo AMDGPUABIInfo::classifyArgumentType(QualType Ty,
9030                                                unsigned &NumRegsLeft) const {
9031   assert(NumRegsLeft <= MaxNumRegsForArgsRet && "register estimate underflow");
9032 
9033   Ty = useFirstFieldIfTransparentUnion(Ty);
9034 
9035   if (isAggregateTypeForABI(Ty)) {
9036     // Records with non-trivial destructors/copy-constructors should not be
9037     // passed by value.
9038     if (auto RAA = getRecordArgABI(Ty, getCXXABI()))
9039       return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
9040 
9041     // Ignore empty structs/unions.
9042     if (isEmptyRecord(getContext(), Ty, true))
9043       return ABIArgInfo::getIgnore();
9044 
9045     // Lower single-element structs to just pass a regular value. TODO: We
9046     // could do reasonable-size multiple-element structs too, using getExpand(),
9047     // though watch out for things like bitfields.
9048     if (const Type *SeltTy = isSingleElementStruct(Ty, getContext()))
9049       return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
9050 
9051     if (const RecordType *RT = Ty->getAs<RecordType>()) {
9052       const RecordDecl *RD = RT->getDecl();
9053       if (RD->hasFlexibleArrayMember())
9054         return DefaultABIInfo::classifyArgumentType(Ty);
9055     }
9056 
9057     // Pack aggregates <= 8 bytes into single VGPR or pair.
9058     uint64_t Size = getContext().getTypeSize(Ty);
9059     if (Size <= 64) {
9060       unsigned NumRegs = (Size + 31) / 32;
9061       NumRegsLeft -= std::min(NumRegsLeft, NumRegs);
9062 
9063       if (Size <= 16)
9064         return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
9065 
9066       if (Size <= 32)
9067         return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
9068 
9069       // XXX: Should this be i64 instead, and should the limit increase?
9070       llvm::Type *I32Ty = llvm::Type::getInt32Ty(getVMContext());
9071       return ABIArgInfo::getDirect(llvm::ArrayType::get(I32Ty, 2));
9072     }
9073 
9074     if (NumRegsLeft > 0) {
9075       unsigned NumRegs = numRegsForType(Ty);
9076       if (NumRegsLeft >= NumRegs) {
9077         NumRegsLeft -= NumRegs;
9078         return ABIArgInfo::getDirect();
9079       }
9080     }
9081   }
9082 
9083   // Otherwise just do the default thing.
9084   ABIArgInfo ArgInfo = DefaultABIInfo::classifyArgumentType(Ty);
9085   if (!ArgInfo.isIndirect()) {
9086     unsigned NumRegs = numRegsForType(Ty);
9087     NumRegsLeft -= std::min(NumRegs, NumRegsLeft);
9088   }
9089 
9090   return ArgInfo;
9091 }
9092 
9093 class AMDGPUTargetCodeGenInfo : public TargetCodeGenInfo {
9094 public:
AMDGPUTargetCodeGenInfo(CodeGenTypes & CGT)9095   AMDGPUTargetCodeGenInfo(CodeGenTypes &CGT)
9096       : TargetCodeGenInfo(std::make_unique<AMDGPUABIInfo>(CGT)) {}
9097   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
9098                            CodeGen::CodeGenModule &M) const override;
9099   unsigned getOpenCLKernelCallingConv() const override;
9100 
9101   llvm::Constant *getNullPointer(const CodeGen::CodeGenModule &CGM,
9102       llvm::PointerType *T, QualType QT) const override;
9103 
getASTAllocaAddressSpace() const9104   LangAS getASTAllocaAddressSpace() const override {
9105     return getLangASFromTargetAS(
9106         getABIInfo().getDataLayout().getAllocaAddrSpace());
9107   }
9108   LangAS getGlobalVarAddressSpace(CodeGenModule &CGM,
9109                                   const VarDecl *D) const override;
9110   llvm::SyncScope::ID getLLVMSyncScopeID(const LangOptions &LangOpts,
9111                                          SyncScope Scope,
9112                                          llvm::AtomicOrdering Ordering,
9113                                          llvm::LLVMContext &Ctx) const override;
9114   llvm::Function *
9115   createEnqueuedBlockKernel(CodeGenFunction &CGF,
9116                             llvm::Function *BlockInvokeFunc,
9117                             llvm::Value *BlockLiteral) const override;
9118   bool shouldEmitStaticExternCAliases() const override;
9119   void setCUDAKernelCallingConvention(const FunctionType *&FT) const override;
9120 };
9121 }
9122 
requiresAMDGPUProtectedVisibility(const Decl * D,llvm::GlobalValue * GV)9123 static bool requiresAMDGPUProtectedVisibility(const Decl *D,
9124                                               llvm::GlobalValue *GV) {
9125   if (GV->getVisibility() != llvm::GlobalValue::HiddenVisibility)
9126     return false;
9127 
9128   return D->hasAttr<OpenCLKernelAttr>() ||
9129          (isa<FunctionDecl>(D) && D->hasAttr<CUDAGlobalAttr>()) ||
9130          (isa<VarDecl>(D) &&
9131           (D->hasAttr<CUDADeviceAttr>() || D->hasAttr<CUDAConstantAttr>() ||
9132            cast<VarDecl>(D)->getType()->isCUDADeviceBuiltinSurfaceType() ||
9133            cast<VarDecl>(D)->getType()->isCUDADeviceBuiltinTextureType()));
9134 }
9135 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & M) const9136 void AMDGPUTargetCodeGenInfo::setTargetAttributes(
9137     const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &M) const {
9138   if (requiresAMDGPUProtectedVisibility(D, GV)) {
9139     GV->setVisibility(llvm::GlobalValue::ProtectedVisibility);
9140     GV->setDSOLocal(true);
9141   }
9142 
9143   if (GV->isDeclaration())
9144     return;
9145   const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
9146   if (!FD)
9147     return;
9148 
9149   llvm::Function *F = cast<llvm::Function>(GV);
9150 
9151   const auto *ReqdWGS = M.getLangOpts().OpenCL ?
9152     FD->getAttr<ReqdWorkGroupSizeAttr>() : nullptr;
9153 
9154 
9155   const bool IsOpenCLKernel = M.getLangOpts().OpenCL &&
9156                               FD->hasAttr<OpenCLKernelAttr>();
9157   const bool IsHIPKernel = M.getLangOpts().HIP &&
9158                            FD->hasAttr<CUDAGlobalAttr>();
9159   if ((IsOpenCLKernel || IsHIPKernel) &&
9160       (M.getTriple().getOS() == llvm::Triple::AMDHSA))
9161     F->addFnAttr("amdgpu-implicitarg-num-bytes", "56");
9162 
9163   if (IsHIPKernel)
9164     F->addFnAttr("uniform-work-group-size", "true");
9165 
9166 
9167   const auto *FlatWGS = FD->getAttr<AMDGPUFlatWorkGroupSizeAttr>();
9168   if (ReqdWGS || FlatWGS) {
9169     unsigned Min = 0;
9170     unsigned Max = 0;
9171     if (FlatWGS) {
9172       Min = FlatWGS->getMin()
9173                 ->EvaluateKnownConstInt(M.getContext())
9174                 .getExtValue();
9175       Max = FlatWGS->getMax()
9176                 ->EvaluateKnownConstInt(M.getContext())
9177                 .getExtValue();
9178     }
9179     if (ReqdWGS && Min == 0 && Max == 0)
9180       Min = Max = ReqdWGS->getXDim() * ReqdWGS->getYDim() * ReqdWGS->getZDim();
9181 
9182     if (Min != 0) {
9183       assert(Min <= Max && "Min must be less than or equal Max");
9184 
9185       std::string AttrVal = llvm::utostr(Min) + "," + llvm::utostr(Max);
9186       F->addFnAttr("amdgpu-flat-work-group-size", AttrVal);
9187     } else
9188       assert(Max == 0 && "Max must be zero");
9189   } else if (IsOpenCLKernel || IsHIPKernel) {
9190     // By default, restrict the maximum size to a value specified by
9191     // --gpu-max-threads-per-block=n or its default value for HIP.
9192     const unsigned OpenCLDefaultMaxWorkGroupSize = 256;
9193     const unsigned DefaultMaxWorkGroupSize =
9194         IsOpenCLKernel ? OpenCLDefaultMaxWorkGroupSize
9195                        : M.getLangOpts().GPUMaxThreadsPerBlock;
9196     std::string AttrVal =
9197         std::string("1,") + llvm::utostr(DefaultMaxWorkGroupSize);
9198     F->addFnAttr("amdgpu-flat-work-group-size", AttrVal);
9199   }
9200 
9201   if (const auto *Attr = FD->getAttr<AMDGPUWavesPerEUAttr>()) {
9202     unsigned Min =
9203         Attr->getMin()->EvaluateKnownConstInt(M.getContext()).getExtValue();
9204     unsigned Max = Attr->getMax() ? Attr->getMax()
9205                                         ->EvaluateKnownConstInt(M.getContext())
9206                                         .getExtValue()
9207                                   : 0;
9208 
9209     if (Min != 0) {
9210       assert((Max == 0 || Min <= Max) && "Min must be less than or equal Max");
9211 
9212       std::string AttrVal = llvm::utostr(Min);
9213       if (Max != 0)
9214         AttrVal = AttrVal + "," + llvm::utostr(Max);
9215       F->addFnAttr("amdgpu-waves-per-eu", AttrVal);
9216     } else
9217       assert(Max == 0 && "Max must be zero");
9218   }
9219 
9220   if (const auto *Attr = FD->getAttr<AMDGPUNumSGPRAttr>()) {
9221     unsigned NumSGPR = Attr->getNumSGPR();
9222 
9223     if (NumSGPR != 0)
9224       F->addFnAttr("amdgpu-num-sgpr", llvm::utostr(NumSGPR));
9225   }
9226 
9227   if (const auto *Attr = FD->getAttr<AMDGPUNumVGPRAttr>()) {
9228     uint32_t NumVGPR = Attr->getNumVGPR();
9229 
9230     if (NumVGPR != 0)
9231       F->addFnAttr("amdgpu-num-vgpr", llvm::utostr(NumVGPR));
9232   }
9233 
9234   if (M.getContext().getTargetInfo().allowAMDGPUUnsafeFPAtomics())
9235     F->addFnAttr("amdgpu-unsafe-fp-atomics", "true");
9236 
9237   if (!getABIInfo().getCodeGenOpts().EmitIEEENaNCompliantInsts)
9238     F->addFnAttr("amdgpu-ieee", "false");
9239 }
9240 
getOpenCLKernelCallingConv() const9241 unsigned AMDGPUTargetCodeGenInfo::getOpenCLKernelCallingConv() const {
9242   return llvm::CallingConv::AMDGPU_KERNEL;
9243 }
9244 
9245 // Currently LLVM assumes null pointers always have value 0,
9246 // which results in incorrectly transformed IR. Therefore, instead of
9247 // emitting null pointers in private and local address spaces, a null
9248 // pointer in generic address space is emitted which is casted to a
9249 // pointer in local or private address space.
getNullPointer(const CodeGen::CodeGenModule & CGM,llvm::PointerType * PT,QualType QT) const9250 llvm::Constant *AMDGPUTargetCodeGenInfo::getNullPointer(
9251     const CodeGen::CodeGenModule &CGM, llvm::PointerType *PT,
9252     QualType QT) const {
9253   if (CGM.getContext().getTargetNullPointerValue(QT) == 0)
9254     return llvm::ConstantPointerNull::get(PT);
9255 
9256   auto &Ctx = CGM.getContext();
9257   auto NPT = llvm::PointerType::get(PT->getElementType(),
9258       Ctx.getTargetAddressSpace(LangAS::opencl_generic));
9259   return llvm::ConstantExpr::getAddrSpaceCast(
9260       llvm::ConstantPointerNull::get(NPT), PT);
9261 }
9262 
9263 LangAS
getGlobalVarAddressSpace(CodeGenModule & CGM,const VarDecl * D) const9264 AMDGPUTargetCodeGenInfo::getGlobalVarAddressSpace(CodeGenModule &CGM,
9265                                                   const VarDecl *D) const {
9266   assert(!CGM.getLangOpts().OpenCL &&
9267          !(CGM.getLangOpts().CUDA && CGM.getLangOpts().CUDAIsDevice) &&
9268          "Address space agnostic languages only");
9269   LangAS DefaultGlobalAS = getLangASFromTargetAS(
9270       CGM.getContext().getTargetAddressSpace(LangAS::opencl_global));
9271   if (!D)
9272     return DefaultGlobalAS;
9273 
9274   LangAS AddrSpace = D->getType().getAddressSpace();
9275   assert(AddrSpace == LangAS::Default || isTargetAddressSpace(AddrSpace));
9276   if (AddrSpace != LangAS::Default)
9277     return AddrSpace;
9278 
9279   if (CGM.isTypeConstant(D->getType(), false)) {
9280     if (auto ConstAS = CGM.getTarget().getConstantAddressSpace())
9281       return ConstAS.getValue();
9282   }
9283   return DefaultGlobalAS;
9284 }
9285 
9286 llvm::SyncScope::ID
getLLVMSyncScopeID(const LangOptions & LangOpts,SyncScope Scope,llvm::AtomicOrdering Ordering,llvm::LLVMContext & Ctx) const9287 AMDGPUTargetCodeGenInfo::getLLVMSyncScopeID(const LangOptions &LangOpts,
9288                                             SyncScope Scope,
9289                                             llvm::AtomicOrdering Ordering,
9290                                             llvm::LLVMContext &Ctx) const {
9291   std::string Name;
9292   switch (Scope) {
9293   case SyncScope::OpenCLWorkGroup:
9294     Name = "workgroup";
9295     break;
9296   case SyncScope::OpenCLDevice:
9297     Name = "agent";
9298     break;
9299   case SyncScope::OpenCLAllSVMDevices:
9300     Name = "";
9301     break;
9302   case SyncScope::OpenCLSubGroup:
9303     Name = "wavefront";
9304   }
9305 
9306   if (Ordering != llvm::AtomicOrdering::SequentiallyConsistent) {
9307     if (!Name.empty())
9308       Name = Twine(Twine(Name) + Twine("-")).str();
9309 
9310     Name = Twine(Twine(Name) + Twine("one-as")).str();
9311   }
9312 
9313   return Ctx.getOrInsertSyncScopeID(Name);
9314 }
9315 
shouldEmitStaticExternCAliases() const9316 bool AMDGPUTargetCodeGenInfo::shouldEmitStaticExternCAliases() const {
9317   return false;
9318 }
9319 
setCUDAKernelCallingConvention(const FunctionType * & FT) const9320 void AMDGPUTargetCodeGenInfo::setCUDAKernelCallingConvention(
9321     const FunctionType *&FT) const {
9322   FT = getABIInfo().getContext().adjustFunctionType(
9323       FT, FT->getExtInfo().withCallingConv(CC_OpenCLKernel));
9324 }
9325 
9326 //===----------------------------------------------------------------------===//
9327 // SPARC v8 ABI Implementation.
9328 // Based on the SPARC Compliance Definition version 2.4.1.
9329 //
9330 // Ensures that complex values are passed in registers.
9331 //
9332 namespace {
9333 class SparcV8ABIInfo : public DefaultABIInfo {
9334 public:
SparcV8ABIInfo(CodeGenTypes & CGT)9335   SparcV8ABIInfo(CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
9336 
9337 private:
9338   ABIArgInfo classifyReturnType(QualType RetTy) const;
9339   void computeInfo(CGFunctionInfo &FI) const override;
9340 };
9341 } // end anonymous namespace
9342 
9343 
9344 ABIArgInfo
classifyReturnType(QualType Ty) const9345 SparcV8ABIInfo::classifyReturnType(QualType Ty) const {
9346   if (Ty->isAnyComplexType()) {
9347     return ABIArgInfo::getDirect();
9348   }
9349   else {
9350     return DefaultABIInfo::classifyReturnType(Ty);
9351   }
9352 }
9353 
computeInfo(CGFunctionInfo & FI) const9354 void SparcV8ABIInfo::computeInfo(CGFunctionInfo &FI) const {
9355 
9356   FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
9357   for (auto &Arg : FI.arguments())
9358     Arg.info = classifyArgumentType(Arg.type);
9359 }
9360 
9361 namespace {
9362 class SparcV8TargetCodeGenInfo : public TargetCodeGenInfo {
9363 public:
SparcV8TargetCodeGenInfo(CodeGenTypes & CGT)9364   SparcV8TargetCodeGenInfo(CodeGenTypes &CGT)
9365       : TargetCodeGenInfo(std::make_unique<SparcV8ABIInfo>(CGT)) {}
9366 };
9367 } // end anonymous namespace
9368 
9369 //===----------------------------------------------------------------------===//
9370 // SPARC v9 ABI Implementation.
9371 // Based on the SPARC Compliance Definition version 2.4.1.
9372 //
9373 // Function arguments a mapped to a nominal "parameter array" and promoted to
9374 // registers depending on their type. Each argument occupies 8 or 16 bytes in
9375 // the array, structs larger than 16 bytes are passed indirectly.
9376 //
9377 // One case requires special care:
9378 //
9379 //   struct mixed {
9380 //     int i;
9381 //     float f;
9382 //   };
9383 //
9384 // When a struct mixed is passed by value, it only occupies 8 bytes in the
9385 // parameter array, but the int is passed in an integer register, and the float
9386 // is passed in a floating point register. This is represented as two arguments
9387 // with the LLVM IR inreg attribute:
9388 //
9389 //   declare void f(i32 inreg %i, float inreg %f)
9390 //
9391 // The code generator will only allocate 4 bytes from the parameter array for
9392 // the inreg arguments. All other arguments are allocated a multiple of 8
9393 // bytes.
9394 //
9395 namespace {
9396 class SparcV9ABIInfo : public ABIInfo {
9397 public:
SparcV9ABIInfo(CodeGenTypes & CGT)9398   SparcV9ABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
9399 
9400 private:
9401   ABIArgInfo classifyType(QualType RetTy, unsigned SizeLimit) const;
9402   void computeInfo(CGFunctionInfo &FI) const override;
9403   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
9404                     QualType Ty) const override;
9405 
9406   // Coercion type builder for structs passed in registers. The coercion type
9407   // serves two purposes:
9408   //
9409   // 1. Pad structs to a multiple of 64 bits, so they are passed 'left-aligned'
9410   //    in registers.
9411   // 2. Expose aligned floating point elements as first-level elements, so the
9412   //    code generator knows to pass them in floating point registers.
9413   //
9414   // We also compute the InReg flag which indicates that the struct contains
9415   // aligned 32-bit floats.
9416   //
9417   struct CoerceBuilder {
9418     llvm::LLVMContext &Context;
9419     const llvm::DataLayout &DL;
9420     SmallVector<llvm::Type*, 8> Elems;
9421     uint64_t Size;
9422     bool InReg;
9423 
CoerceBuilder__anon666ee6d71711::SparcV9ABIInfo::CoerceBuilder9424     CoerceBuilder(llvm::LLVMContext &c, const llvm::DataLayout &dl)
9425       : Context(c), DL(dl), Size(0), InReg(false) {}
9426 
9427     // Pad Elems with integers until Size is ToSize.
pad__anon666ee6d71711::SparcV9ABIInfo::CoerceBuilder9428     void pad(uint64_t ToSize) {
9429       assert(ToSize >= Size && "Cannot remove elements");
9430       if (ToSize == Size)
9431         return;
9432 
9433       // Finish the current 64-bit word.
9434       uint64_t Aligned = llvm::alignTo(Size, 64);
9435       if (Aligned > Size && Aligned <= ToSize) {
9436         Elems.push_back(llvm::IntegerType::get(Context, Aligned - Size));
9437         Size = Aligned;
9438       }
9439 
9440       // Add whole 64-bit words.
9441       while (Size + 64 <= ToSize) {
9442         Elems.push_back(llvm::Type::getInt64Ty(Context));
9443         Size += 64;
9444       }
9445 
9446       // Final in-word padding.
9447       if (Size < ToSize) {
9448         Elems.push_back(llvm::IntegerType::get(Context, ToSize - Size));
9449         Size = ToSize;
9450       }
9451     }
9452 
9453     // Add a floating point element at Offset.
addFloat__anon666ee6d71711::SparcV9ABIInfo::CoerceBuilder9454     void addFloat(uint64_t Offset, llvm::Type *Ty, unsigned Bits) {
9455       // Unaligned floats are treated as integers.
9456       if (Offset % Bits)
9457         return;
9458       // The InReg flag is only required if there are any floats < 64 bits.
9459       if (Bits < 64)
9460         InReg = true;
9461       pad(Offset);
9462       Elems.push_back(Ty);
9463       Size = Offset + Bits;
9464     }
9465 
9466     // Add a struct type to the coercion type, starting at Offset (in bits).
addStruct__anon666ee6d71711::SparcV9ABIInfo::CoerceBuilder9467     void addStruct(uint64_t Offset, llvm::StructType *StrTy) {
9468       const llvm::StructLayout *Layout = DL.getStructLayout(StrTy);
9469       for (unsigned i = 0, e = StrTy->getNumElements(); i != e; ++i) {
9470         llvm::Type *ElemTy = StrTy->getElementType(i);
9471         uint64_t ElemOffset = Offset + Layout->getElementOffsetInBits(i);
9472         switch (ElemTy->getTypeID()) {
9473         case llvm::Type::StructTyID:
9474           addStruct(ElemOffset, cast<llvm::StructType>(ElemTy));
9475           break;
9476         case llvm::Type::FloatTyID:
9477           addFloat(ElemOffset, ElemTy, 32);
9478           break;
9479         case llvm::Type::DoubleTyID:
9480           addFloat(ElemOffset, ElemTy, 64);
9481           break;
9482         case llvm::Type::FP128TyID:
9483           addFloat(ElemOffset, ElemTy, 128);
9484           break;
9485         case llvm::Type::PointerTyID:
9486           if (ElemOffset % 64 == 0) {
9487             pad(ElemOffset);
9488             Elems.push_back(ElemTy);
9489             Size += 64;
9490           }
9491           break;
9492         default:
9493           break;
9494         }
9495       }
9496     }
9497 
9498     // Check if Ty is a usable substitute for the coercion type.
isUsableType__anon666ee6d71711::SparcV9ABIInfo::CoerceBuilder9499     bool isUsableType(llvm::StructType *Ty) const {
9500       return llvm::makeArrayRef(Elems) == Ty->elements();
9501     }
9502 
9503     // Get the coercion type as a literal struct type.
getType__anon666ee6d71711::SparcV9ABIInfo::CoerceBuilder9504     llvm::Type *getType() const {
9505       if (Elems.size() == 1)
9506         return Elems.front();
9507       else
9508         return llvm::StructType::get(Context, Elems);
9509     }
9510   };
9511 };
9512 } // end anonymous namespace
9513 
9514 ABIArgInfo
classifyType(QualType Ty,unsigned SizeLimit) const9515 SparcV9ABIInfo::classifyType(QualType Ty, unsigned SizeLimit) const {
9516   if (Ty->isVoidType())
9517     return ABIArgInfo::getIgnore();
9518 
9519   uint64_t Size = getContext().getTypeSize(Ty);
9520 
9521   // Anything too big to fit in registers is passed with an explicit indirect
9522   // pointer / sret pointer.
9523   if (Size > SizeLimit)
9524     return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
9525 
9526   // Treat an enum type as its underlying type.
9527   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
9528     Ty = EnumTy->getDecl()->getIntegerType();
9529 
9530   // Integer types smaller than a register are extended.
9531   if (Size < 64 && Ty->isIntegerType())
9532     return ABIArgInfo::getExtend(Ty);
9533 
9534   if (const auto *EIT = Ty->getAs<ExtIntType>())
9535     if (EIT->getNumBits() < 64)
9536       return ABIArgInfo::getExtend(Ty);
9537 
9538   // Other non-aggregates go in registers.
9539   if (!isAggregateTypeForABI(Ty))
9540     return ABIArgInfo::getDirect();
9541 
9542   // If a C++ object has either a non-trivial copy constructor or a non-trivial
9543   // destructor, it is passed with an explicit indirect pointer / sret pointer.
9544   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
9545     return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
9546 
9547   // This is a small aggregate type that should be passed in registers.
9548   // Build a coercion type from the LLVM struct type.
9549   llvm::StructType *StrTy = dyn_cast<llvm::StructType>(CGT.ConvertType(Ty));
9550   if (!StrTy)
9551     return ABIArgInfo::getDirect();
9552 
9553   CoerceBuilder CB(getVMContext(), getDataLayout());
9554   CB.addStruct(0, StrTy);
9555   CB.pad(llvm::alignTo(CB.DL.getTypeSizeInBits(StrTy), 64));
9556 
9557   // Try to use the original type for coercion.
9558   llvm::Type *CoerceTy = CB.isUsableType(StrTy) ? StrTy : CB.getType();
9559 
9560   if (CB.InReg)
9561     return ABIArgInfo::getDirectInReg(CoerceTy);
9562   else
9563     return ABIArgInfo::getDirect(CoerceTy);
9564 }
9565 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const9566 Address SparcV9ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
9567                                   QualType Ty) const {
9568   ABIArgInfo AI = classifyType(Ty, 16 * 8);
9569   llvm::Type *ArgTy = CGT.ConvertType(Ty);
9570   if (AI.canHaveCoerceToType() && !AI.getCoerceToType())
9571     AI.setCoerceToType(ArgTy);
9572 
9573   CharUnits SlotSize = CharUnits::fromQuantity(8);
9574 
9575   CGBuilderTy &Builder = CGF.Builder;
9576   Address Addr(Builder.CreateLoad(VAListAddr, "ap.cur"), SlotSize);
9577   llvm::Type *ArgPtrTy = llvm::PointerType::getUnqual(ArgTy);
9578 
9579   auto TypeInfo = getContext().getTypeInfoInChars(Ty);
9580 
9581   Address ArgAddr = Address::invalid();
9582   CharUnits Stride;
9583   switch (AI.getKind()) {
9584   case ABIArgInfo::Expand:
9585   case ABIArgInfo::CoerceAndExpand:
9586   case ABIArgInfo::InAlloca:
9587     llvm_unreachable("Unsupported ABI kind for va_arg");
9588 
9589   case ABIArgInfo::Extend: {
9590     Stride = SlotSize;
9591     CharUnits Offset = SlotSize - TypeInfo.Width;
9592     ArgAddr = Builder.CreateConstInBoundsByteGEP(Addr, Offset, "extend");
9593     break;
9594   }
9595 
9596   case ABIArgInfo::Direct: {
9597     auto AllocSize = getDataLayout().getTypeAllocSize(AI.getCoerceToType());
9598     Stride = CharUnits::fromQuantity(AllocSize).alignTo(SlotSize);
9599     ArgAddr = Addr;
9600     break;
9601   }
9602 
9603   case ABIArgInfo::Indirect:
9604   case ABIArgInfo::IndirectAliased:
9605     Stride = SlotSize;
9606     ArgAddr = Builder.CreateElementBitCast(Addr, ArgPtrTy, "indirect");
9607     ArgAddr = Address(Builder.CreateLoad(ArgAddr, "indirect.arg"),
9608                       TypeInfo.Align);
9609     break;
9610 
9611   case ABIArgInfo::Ignore:
9612     return Address(llvm::UndefValue::get(ArgPtrTy), TypeInfo.Align);
9613   }
9614 
9615   // Update VAList.
9616   Address NextPtr = Builder.CreateConstInBoundsByteGEP(Addr, Stride, "ap.next");
9617   Builder.CreateStore(NextPtr.getPointer(), VAListAddr);
9618 
9619   return Builder.CreateBitCast(ArgAddr, ArgPtrTy, "arg.addr");
9620 }
9621 
computeInfo(CGFunctionInfo & FI) const9622 void SparcV9ABIInfo::computeInfo(CGFunctionInfo &FI) const {
9623   FI.getReturnInfo() = classifyType(FI.getReturnType(), 32 * 8);
9624   for (auto &I : FI.arguments())
9625     I.info = classifyType(I.type, 16 * 8);
9626 }
9627 
9628 namespace {
9629 class SparcV9TargetCodeGenInfo : public TargetCodeGenInfo {
9630 public:
SparcV9TargetCodeGenInfo(CodeGenTypes & CGT)9631   SparcV9TargetCodeGenInfo(CodeGenTypes &CGT)
9632       : TargetCodeGenInfo(std::make_unique<SparcV9ABIInfo>(CGT)) {}
9633 
getDwarfEHStackPointer(CodeGen::CodeGenModule & M) const9634   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
9635     return 14;
9636   }
9637 
9638   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
9639                                llvm::Value *Address) const override;
9640 };
9641 } // end anonymous namespace
9642 
9643 bool
initDwarfEHRegSizeTable(CodeGen::CodeGenFunction & CGF,llvm::Value * Address) const9644 SparcV9TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
9645                                                 llvm::Value *Address) const {
9646   // This is calculated from the LLVM and GCC tables and verified
9647   // against gcc output.  AFAIK all ABIs use the same encoding.
9648 
9649   CodeGen::CGBuilderTy &Builder = CGF.Builder;
9650 
9651   llvm::IntegerType *i8 = CGF.Int8Ty;
9652   llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
9653   llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
9654 
9655   // 0-31: the 8-byte general-purpose registers
9656   AssignToArrayRange(Builder, Address, Eight8, 0, 31);
9657 
9658   // 32-63: f0-31, the 4-byte floating-point registers
9659   AssignToArrayRange(Builder, Address, Four8, 32, 63);
9660 
9661   //   Y   = 64
9662   //   PSR = 65
9663   //   WIM = 66
9664   //   TBR = 67
9665   //   PC  = 68
9666   //   NPC = 69
9667   //   FSR = 70
9668   //   CSR = 71
9669   AssignToArrayRange(Builder, Address, Eight8, 64, 71);
9670 
9671   // 72-87: d0-15, the 8-byte floating-point registers
9672   AssignToArrayRange(Builder, Address, Eight8, 72, 87);
9673 
9674   return false;
9675 }
9676 
9677 // ARC ABI implementation.
9678 namespace {
9679 
9680 class ARCABIInfo : public DefaultABIInfo {
9681 public:
9682   using DefaultABIInfo::DefaultABIInfo;
9683 
9684 private:
9685   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
9686                     QualType Ty) const override;
9687 
updateState(const ABIArgInfo & Info,QualType Ty,CCState & State) const9688   void updateState(const ABIArgInfo &Info, QualType Ty, CCState &State) const {
9689     if (!State.FreeRegs)
9690       return;
9691     if (Info.isIndirect() && Info.getInReg())
9692       State.FreeRegs--;
9693     else if (Info.isDirect() && Info.getInReg()) {
9694       unsigned sz = (getContext().getTypeSize(Ty) + 31) / 32;
9695       if (sz < State.FreeRegs)
9696         State.FreeRegs -= sz;
9697       else
9698         State.FreeRegs = 0;
9699     }
9700   }
9701 
computeInfo(CGFunctionInfo & FI) const9702   void computeInfo(CGFunctionInfo &FI) const override {
9703     CCState State(FI);
9704     // ARC uses 8 registers to pass arguments.
9705     State.FreeRegs = 8;
9706 
9707     if (!getCXXABI().classifyReturnType(FI))
9708       FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
9709     updateState(FI.getReturnInfo(), FI.getReturnType(), State);
9710     for (auto &I : FI.arguments()) {
9711       I.info = classifyArgumentType(I.type, State.FreeRegs);
9712       updateState(I.info, I.type, State);
9713     }
9714   }
9715 
9716   ABIArgInfo getIndirectByRef(QualType Ty, bool HasFreeRegs) const;
9717   ABIArgInfo getIndirectByValue(QualType Ty) const;
9718   ABIArgInfo classifyArgumentType(QualType Ty, uint8_t FreeRegs) const;
9719   ABIArgInfo classifyReturnType(QualType RetTy) const;
9720 };
9721 
9722 class ARCTargetCodeGenInfo : public TargetCodeGenInfo {
9723 public:
ARCTargetCodeGenInfo(CodeGenTypes & CGT)9724   ARCTargetCodeGenInfo(CodeGenTypes &CGT)
9725       : TargetCodeGenInfo(std::make_unique<ARCABIInfo>(CGT)) {}
9726 };
9727 
9728 
getIndirectByRef(QualType Ty,bool HasFreeRegs) const9729 ABIArgInfo ARCABIInfo::getIndirectByRef(QualType Ty, bool HasFreeRegs) const {
9730   return HasFreeRegs ? getNaturalAlignIndirectInReg(Ty) :
9731                        getNaturalAlignIndirect(Ty, false);
9732 }
9733 
getIndirectByValue(QualType Ty) const9734 ABIArgInfo ARCABIInfo::getIndirectByValue(QualType Ty) const {
9735   // Compute the byval alignment.
9736   const unsigned MinABIStackAlignInBytes = 4;
9737   unsigned TypeAlign = getContext().getTypeAlign(Ty) / 8;
9738   return ABIArgInfo::getIndirect(CharUnits::fromQuantity(4), /*ByVal=*/true,
9739                                  TypeAlign > MinABIStackAlignInBytes);
9740 }
9741 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const9742 Address ARCABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
9743                               QualType Ty) const {
9744   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*indirect*/ false,
9745                           getContext().getTypeInfoInChars(Ty),
9746                           CharUnits::fromQuantity(4), true);
9747 }
9748 
classifyArgumentType(QualType Ty,uint8_t FreeRegs) const9749 ABIArgInfo ARCABIInfo::classifyArgumentType(QualType Ty,
9750                                             uint8_t FreeRegs) const {
9751   // Handle the generic C++ ABI.
9752   const RecordType *RT = Ty->getAs<RecordType>();
9753   if (RT) {
9754     CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, getCXXABI());
9755     if (RAA == CGCXXABI::RAA_Indirect)
9756       return getIndirectByRef(Ty, FreeRegs > 0);
9757 
9758     if (RAA == CGCXXABI::RAA_DirectInMemory)
9759       return getIndirectByValue(Ty);
9760   }
9761 
9762   // Treat an enum type as its underlying type.
9763   if (const EnumType *EnumTy = Ty->getAs<EnumType>())
9764     Ty = EnumTy->getDecl()->getIntegerType();
9765 
9766   auto SizeInRegs = llvm::alignTo(getContext().getTypeSize(Ty), 32) / 32;
9767 
9768   if (isAggregateTypeForABI(Ty)) {
9769     // Structures with flexible arrays are always indirect.
9770     if (RT && RT->getDecl()->hasFlexibleArrayMember())
9771       return getIndirectByValue(Ty);
9772 
9773     // Ignore empty structs/unions.
9774     if (isEmptyRecord(getContext(), Ty, true))
9775       return ABIArgInfo::getIgnore();
9776 
9777     llvm::LLVMContext &LLVMContext = getVMContext();
9778 
9779     llvm::IntegerType *Int32 = llvm::Type::getInt32Ty(LLVMContext);
9780     SmallVector<llvm::Type *, 3> Elements(SizeInRegs, Int32);
9781     llvm::Type *Result = llvm::StructType::get(LLVMContext, Elements);
9782 
9783     return FreeRegs >= SizeInRegs ?
9784         ABIArgInfo::getDirectInReg(Result) :
9785         ABIArgInfo::getDirect(Result, 0, nullptr, false);
9786   }
9787 
9788   if (const auto *EIT = Ty->getAs<ExtIntType>())
9789     if (EIT->getNumBits() > 64)
9790       return getIndirectByValue(Ty);
9791 
9792   return isPromotableIntegerTypeForABI(Ty)
9793              ? (FreeRegs >= SizeInRegs ? ABIArgInfo::getExtendInReg(Ty)
9794                                        : ABIArgInfo::getExtend(Ty))
9795              : (FreeRegs >= SizeInRegs ? ABIArgInfo::getDirectInReg()
9796                                        : ABIArgInfo::getDirect());
9797 }
9798 
classifyReturnType(QualType RetTy) const9799 ABIArgInfo ARCABIInfo::classifyReturnType(QualType RetTy) const {
9800   if (RetTy->isAnyComplexType())
9801     return ABIArgInfo::getDirectInReg();
9802 
9803   // Arguments of size > 4 registers are indirect.
9804   auto RetSize = llvm::alignTo(getContext().getTypeSize(RetTy), 32) / 32;
9805   if (RetSize > 4)
9806     return getIndirectByRef(RetTy, /*HasFreeRegs*/ true);
9807 
9808   return DefaultABIInfo::classifyReturnType(RetTy);
9809 }
9810 
9811 } // End anonymous namespace.
9812 
9813 //===----------------------------------------------------------------------===//
9814 // XCore ABI Implementation
9815 //===----------------------------------------------------------------------===//
9816 
9817 namespace {
9818 
9819 /// A SmallStringEnc instance is used to build up the TypeString by passing
9820 /// it by reference between functions that append to it.
9821 typedef llvm::SmallString<128> SmallStringEnc;
9822 
9823 /// TypeStringCache caches the meta encodings of Types.
9824 ///
9825 /// The reason for caching TypeStrings is two fold:
9826 ///   1. To cache a type's encoding for later uses;
9827 ///   2. As a means to break recursive member type inclusion.
9828 ///
9829 /// A cache Entry can have a Status of:
9830 ///   NonRecursive:   The type encoding is not recursive;
9831 ///   Recursive:      The type encoding is recursive;
9832 ///   Incomplete:     An incomplete TypeString;
9833 ///   IncompleteUsed: An incomplete TypeString that has been used in a
9834 ///                   Recursive type encoding.
9835 ///
9836 /// A NonRecursive entry will have all of its sub-members expanded as fully
9837 /// as possible. Whilst it may contain types which are recursive, the type
9838 /// itself is not recursive and thus its encoding may be safely used whenever
9839 /// the type is encountered.
9840 ///
9841 /// A Recursive entry will have all of its sub-members expanded as fully as
9842 /// possible. The type itself is recursive and it may contain other types which
9843 /// are recursive. The Recursive encoding must not be used during the expansion
9844 /// of a recursive type's recursive branch. For simplicity the code uses
9845 /// IncompleteCount to reject all usage of Recursive encodings for member types.
9846 ///
9847 /// An Incomplete entry is always a RecordType and only encodes its
9848 /// identifier e.g. "s(S){}". Incomplete 'StubEnc' entries are ephemeral and
9849 /// are placed into the cache during type expansion as a means to identify and
9850 /// handle recursive inclusion of types as sub-members. If there is recursion
9851 /// the entry becomes IncompleteUsed.
9852 ///
9853 /// During the expansion of a RecordType's members:
9854 ///
9855 ///   If the cache contains a NonRecursive encoding for the member type, the
9856 ///   cached encoding is used;
9857 ///
9858 ///   If the cache contains a Recursive encoding for the member type, the
9859 ///   cached encoding is 'Swapped' out, as it may be incorrect, and...
9860 ///
9861 ///   If the member is a RecordType, an Incomplete encoding is placed into the
9862 ///   cache to break potential recursive inclusion of itself as a sub-member;
9863 ///
9864 ///   Once a member RecordType has been expanded, its temporary incomplete
9865 ///   entry is removed from the cache. If a Recursive encoding was swapped out
9866 ///   it is swapped back in;
9867 ///
9868 ///   If an incomplete entry is used to expand a sub-member, the incomplete
9869 ///   entry is marked as IncompleteUsed. The cache keeps count of how many
9870 ///   IncompleteUsed entries it currently contains in IncompleteUsedCount;
9871 ///
9872 ///   If a member's encoding is found to be a NonRecursive or Recursive viz:
9873 ///   IncompleteUsedCount==0, the member's encoding is added to the cache.
9874 ///   Else the member is part of a recursive type and thus the recursion has
9875 ///   been exited too soon for the encoding to be correct for the member.
9876 ///
9877 class TypeStringCache {
9878   enum Status {NonRecursive, Recursive, Incomplete, IncompleteUsed};
9879   struct Entry {
9880     std::string Str;     // The encoded TypeString for the type.
9881     enum Status State;   // Information about the encoding in 'Str'.
9882     std::string Swapped; // A temporary place holder for a Recursive encoding
9883                          // during the expansion of RecordType's members.
9884   };
9885   std::map<const IdentifierInfo *, struct Entry> Map;
9886   unsigned IncompleteCount;     // Number of Incomplete entries in the Map.
9887   unsigned IncompleteUsedCount; // Number of IncompleteUsed entries in the Map.
9888 public:
TypeStringCache()9889   TypeStringCache() : IncompleteCount(0), IncompleteUsedCount(0) {}
9890   void addIncomplete(const IdentifierInfo *ID, std::string StubEnc);
9891   bool removeIncomplete(const IdentifierInfo *ID);
9892   void addIfComplete(const IdentifierInfo *ID, StringRef Str,
9893                      bool IsRecursive);
9894   StringRef lookupStr(const IdentifierInfo *ID);
9895 };
9896 
9897 /// TypeString encodings for enum & union fields must be order.
9898 /// FieldEncoding is a helper for this ordering process.
9899 class FieldEncoding {
9900   bool HasName;
9901   std::string Enc;
9902 public:
FieldEncoding(bool b,SmallStringEnc & e)9903   FieldEncoding(bool b, SmallStringEnc &e) : HasName(b), Enc(e.c_str()) {}
str()9904   StringRef str() { return Enc; }
operator <(const FieldEncoding & rhs) const9905   bool operator<(const FieldEncoding &rhs) const {
9906     if (HasName != rhs.HasName) return HasName;
9907     return Enc < rhs.Enc;
9908   }
9909 };
9910 
9911 class XCoreABIInfo : public DefaultABIInfo {
9912 public:
XCoreABIInfo(CodeGen::CodeGenTypes & CGT)9913   XCoreABIInfo(CodeGen::CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
9914   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
9915                     QualType Ty) const override;
9916 };
9917 
9918 class XCoreTargetCodeGenInfo : public TargetCodeGenInfo {
9919   mutable TypeStringCache TSC;
9920   void emitTargetMD(const Decl *D, llvm::GlobalValue *GV,
9921                     const CodeGen::CodeGenModule &M) const;
9922 
9923 public:
XCoreTargetCodeGenInfo(CodeGenTypes & CGT)9924   XCoreTargetCodeGenInfo(CodeGenTypes &CGT)
9925       : TargetCodeGenInfo(std::make_unique<XCoreABIInfo>(CGT)) {}
9926   void emitTargetMetadata(CodeGen::CodeGenModule &CGM,
9927                           const llvm::MapVector<GlobalDecl, StringRef>
9928                               &MangledDeclNames) const override;
9929 };
9930 
9931 } // End anonymous namespace.
9932 
9933 // TODO: this implementation is likely now redundant with the default
9934 // EmitVAArg.
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const9935 Address XCoreABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
9936                                 QualType Ty) const {
9937   CGBuilderTy &Builder = CGF.Builder;
9938 
9939   // Get the VAList.
9940   CharUnits SlotSize = CharUnits::fromQuantity(4);
9941   Address AP(Builder.CreateLoad(VAListAddr), SlotSize);
9942 
9943   // Handle the argument.
9944   ABIArgInfo AI = classifyArgumentType(Ty);
9945   CharUnits TypeAlign = getContext().getTypeAlignInChars(Ty);
9946   llvm::Type *ArgTy = CGT.ConvertType(Ty);
9947   if (AI.canHaveCoerceToType() && !AI.getCoerceToType())
9948     AI.setCoerceToType(ArgTy);
9949   llvm::Type *ArgPtrTy = llvm::PointerType::getUnqual(ArgTy);
9950 
9951   Address Val = Address::invalid();
9952   CharUnits ArgSize = CharUnits::Zero();
9953   switch (AI.getKind()) {
9954   case ABIArgInfo::Expand:
9955   case ABIArgInfo::CoerceAndExpand:
9956   case ABIArgInfo::InAlloca:
9957     llvm_unreachable("Unsupported ABI kind for va_arg");
9958   case ABIArgInfo::Ignore:
9959     Val = Address(llvm::UndefValue::get(ArgPtrTy), TypeAlign);
9960     ArgSize = CharUnits::Zero();
9961     break;
9962   case ABIArgInfo::Extend:
9963   case ABIArgInfo::Direct:
9964     Val = Builder.CreateBitCast(AP, ArgPtrTy);
9965     ArgSize = CharUnits::fromQuantity(
9966                        getDataLayout().getTypeAllocSize(AI.getCoerceToType()));
9967     ArgSize = ArgSize.alignTo(SlotSize);
9968     break;
9969   case ABIArgInfo::Indirect:
9970   case ABIArgInfo::IndirectAliased:
9971     Val = Builder.CreateElementBitCast(AP, ArgPtrTy);
9972     Val = Address(Builder.CreateLoad(Val), TypeAlign);
9973     ArgSize = SlotSize;
9974     break;
9975   }
9976 
9977   // Increment the VAList.
9978   if (!ArgSize.isZero()) {
9979     Address APN = Builder.CreateConstInBoundsByteGEP(AP, ArgSize);
9980     Builder.CreateStore(APN.getPointer(), VAListAddr);
9981   }
9982 
9983   return Val;
9984 }
9985 
9986 /// During the expansion of a RecordType, an incomplete TypeString is placed
9987 /// into the cache as a means to identify and break recursion.
9988 /// If there is a Recursive encoding in the cache, it is swapped out and will
9989 /// be reinserted by removeIncomplete().
9990 /// All other types of encoding should have been used rather than arriving here.
addIncomplete(const IdentifierInfo * ID,std::string StubEnc)9991 void TypeStringCache::addIncomplete(const IdentifierInfo *ID,
9992                                     std::string StubEnc) {
9993   if (!ID)
9994     return;
9995   Entry &E = Map[ID];
9996   assert( (E.Str.empty() || E.State == Recursive) &&
9997          "Incorrectly use of addIncomplete");
9998   assert(!StubEnc.empty() && "Passing an empty string to addIncomplete()");
9999   E.Swapped.swap(E.Str); // swap out the Recursive
10000   E.Str.swap(StubEnc);
10001   E.State = Incomplete;
10002   ++IncompleteCount;
10003 }
10004 
10005 /// Once the RecordType has been expanded, the temporary incomplete TypeString
10006 /// must be removed from the cache.
10007 /// If a Recursive was swapped out by addIncomplete(), it will be replaced.
10008 /// Returns true if the RecordType was defined recursively.
removeIncomplete(const IdentifierInfo * ID)10009 bool TypeStringCache::removeIncomplete(const IdentifierInfo *ID) {
10010   if (!ID)
10011     return false;
10012   auto I = Map.find(ID);
10013   assert(I != Map.end() && "Entry not present");
10014   Entry &E = I->second;
10015   assert( (E.State == Incomplete ||
10016            E.State == IncompleteUsed) &&
10017          "Entry must be an incomplete type");
10018   bool IsRecursive = false;
10019   if (E.State == IncompleteUsed) {
10020     // We made use of our Incomplete encoding, thus we are recursive.
10021     IsRecursive = true;
10022     --IncompleteUsedCount;
10023   }
10024   if (E.Swapped.empty())
10025     Map.erase(I);
10026   else {
10027     // Swap the Recursive back.
10028     E.Swapped.swap(E.Str);
10029     E.Swapped.clear();
10030     E.State = Recursive;
10031   }
10032   --IncompleteCount;
10033   return IsRecursive;
10034 }
10035 
10036 /// Add the encoded TypeString to the cache only if it is NonRecursive or
10037 /// Recursive (viz: all sub-members were expanded as fully as possible).
addIfComplete(const IdentifierInfo * ID,StringRef Str,bool IsRecursive)10038 void TypeStringCache::addIfComplete(const IdentifierInfo *ID, StringRef Str,
10039                                     bool IsRecursive) {
10040   if (!ID || IncompleteUsedCount)
10041     return; // No key or it is is an incomplete sub-type so don't add.
10042   Entry &E = Map[ID];
10043   if (IsRecursive && !E.Str.empty()) {
10044     assert(E.State==Recursive && E.Str.size() == Str.size() &&
10045            "This is not the same Recursive entry");
10046     // The parent container was not recursive after all, so we could have used
10047     // this Recursive sub-member entry after all, but we assumed the worse when
10048     // we started viz: IncompleteCount!=0.
10049     return;
10050   }
10051   assert(E.Str.empty() && "Entry already present");
10052   E.Str = Str.str();
10053   E.State = IsRecursive? Recursive : NonRecursive;
10054 }
10055 
10056 /// Return a cached TypeString encoding for the ID. If there isn't one, or we
10057 /// are recursively expanding a type (IncompleteCount != 0) and the cached
10058 /// encoding is Recursive, return an empty StringRef.
lookupStr(const IdentifierInfo * ID)10059 StringRef TypeStringCache::lookupStr(const IdentifierInfo *ID) {
10060   if (!ID)
10061     return StringRef();   // We have no key.
10062   auto I = Map.find(ID);
10063   if (I == Map.end())
10064     return StringRef();   // We have no encoding.
10065   Entry &E = I->second;
10066   if (E.State == Recursive && IncompleteCount)
10067     return StringRef();   // We don't use Recursive encodings for member types.
10068 
10069   if (E.State == Incomplete) {
10070     // The incomplete type is being used to break out of recursion.
10071     E.State = IncompleteUsed;
10072     ++IncompleteUsedCount;
10073   }
10074   return E.Str;
10075 }
10076 
10077 /// The XCore ABI includes a type information section that communicates symbol
10078 /// type information to the linker. The linker uses this information to verify
10079 /// safety/correctness of things such as array bound and pointers et al.
10080 /// The ABI only requires C (and XC) language modules to emit TypeStrings.
10081 /// This type information (TypeString) is emitted into meta data for all global
10082 /// symbols: definitions, declarations, functions & variables.
10083 ///
10084 /// The TypeString carries type, qualifier, name, size & value details.
10085 /// Please see 'Tools Development Guide' section 2.16.2 for format details:
10086 /// https://www.xmos.com/download/public/Tools-Development-Guide%28X9114A%29.pdf
10087 /// The output is tested by test/CodeGen/xcore-stringtype.c.
10088 ///
10089 static bool getTypeString(SmallStringEnc &Enc, const Decl *D,
10090                           const CodeGen::CodeGenModule &CGM,
10091                           TypeStringCache &TSC);
10092 
10093 /// XCore uses emitTargetMD to emit TypeString metadata for global symbols.
emitTargetMD(const Decl * D,llvm::GlobalValue * GV,const CodeGen::CodeGenModule & CGM) const10094 void XCoreTargetCodeGenInfo::emitTargetMD(
10095     const Decl *D, llvm::GlobalValue *GV,
10096     const CodeGen::CodeGenModule &CGM) const {
10097   SmallStringEnc Enc;
10098   if (getTypeString(Enc, D, CGM, TSC)) {
10099     llvm::LLVMContext &Ctx = CGM.getModule().getContext();
10100     llvm::Metadata *MDVals[] = {llvm::ConstantAsMetadata::get(GV),
10101                                 llvm::MDString::get(Ctx, Enc.str())};
10102     llvm::NamedMDNode *MD =
10103       CGM.getModule().getOrInsertNamedMetadata("xcore.typestrings");
10104     MD->addOperand(llvm::MDNode::get(Ctx, MDVals));
10105   }
10106 }
10107 
emitTargetMetadata(CodeGen::CodeGenModule & CGM,const llvm::MapVector<GlobalDecl,StringRef> & MangledDeclNames) const10108 void XCoreTargetCodeGenInfo::emitTargetMetadata(
10109     CodeGen::CodeGenModule &CGM,
10110     const llvm::MapVector<GlobalDecl, StringRef> &MangledDeclNames) const {
10111   // Warning, new MangledDeclNames may be appended within this loop.
10112   // We rely on MapVector insertions adding new elements to the end
10113   // of the container.
10114   for (unsigned I = 0; I != MangledDeclNames.size(); ++I) {
10115     auto Val = *(MangledDeclNames.begin() + I);
10116     llvm::GlobalValue *GV = CGM.GetGlobalValue(Val.second);
10117     if (GV) {
10118       const Decl *D = Val.first.getDecl()->getMostRecentDecl();
10119       emitTargetMD(D, GV, CGM);
10120     }
10121   }
10122 }
10123 //===----------------------------------------------------------------------===//
10124 // SPIR ABI Implementation
10125 //===----------------------------------------------------------------------===//
10126 
10127 namespace {
10128 class SPIRABIInfo : public DefaultABIInfo {
10129 public:
SPIRABIInfo(CodeGenTypes & CGT)10130   SPIRABIInfo(CodeGenTypes &CGT) : DefaultABIInfo(CGT) { setCCs(); }
10131 
10132 private:
10133   void setCCs();
10134 };
10135 } // end anonymous namespace
10136 namespace {
10137 class SPIRTargetCodeGenInfo : public TargetCodeGenInfo {
10138 public:
SPIRTargetCodeGenInfo(CodeGen::CodeGenTypes & CGT)10139   SPIRTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
10140       : TargetCodeGenInfo(std::make_unique<SPIRABIInfo>(CGT)) {}
10141 
getASTAllocaAddressSpace() const10142   LangAS getASTAllocaAddressSpace() const override {
10143     return getLangASFromTargetAS(
10144         getABIInfo().getDataLayout().getAllocaAddrSpace());
10145   }
10146 
10147   unsigned getOpenCLKernelCallingConv() const override;
10148 };
10149 
10150 } // End anonymous namespace.
setCCs()10151 void SPIRABIInfo::setCCs() {
10152   assert(getRuntimeCC() == llvm::CallingConv::C);
10153   RuntimeCC = llvm::CallingConv::SPIR_FUNC;
10154 }
10155 
10156 namespace clang {
10157 namespace CodeGen {
computeSPIRKernelABIInfo(CodeGenModule & CGM,CGFunctionInfo & FI)10158 void computeSPIRKernelABIInfo(CodeGenModule &CGM, CGFunctionInfo &FI) {
10159   DefaultABIInfo SPIRABI(CGM.getTypes());
10160   SPIRABI.computeInfo(FI);
10161 }
10162 }
10163 }
10164 
getOpenCLKernelCallingConv() const10165 unsigned SPIRTargetCodeGenInfo::getOpenCLKernelCallingConv() const {
10166   return llvm::CallingConv::SPIR_KERNEL;
10167 }
10168 
10169 static bool appendType(SmallStringEnc &Enc, QualType QType,
10170                        const CodeGen::CodeGenModule &CGM,
10171                        TypeStringCache &TSC);
10172 
10173 /// Helper function for appendRecordType().
10174 /// Builds a SmallVector containing the encoded field types in declaration
10175 /// order.
extractFieldType(SmallVectorImpl<FieldEncoding> & FE,const RecordDecl * RD,const CodeGen::CodeGenModule & CGM,TypeStringCache & TSC)10176 static bool extractFieldType(SmallVectorImpl<FieldEncoding> &FE,
10177                              const RecordDecl *RD,
10178                              const CodeGen::CodeGenModule &CGM,
10179                              TypeStringCache &TSC) {
10180   for (const auto *Field : RD->fields()) {
10181     SmallStringEnc Enc;
10182     Enc += "m(";
10183     Enc += Field->getName();
10184     Enc += "){";
10185     if (Field->isBitField()) {
10186       Enc += "b(";
10187       llvm::raw_svector_ostream OS(Enc);
10188       OS << Field->getBitWidthValue(CGM.getContext());
10189       Enc += ':';
10190     }
10191     if (!appendType(Enc, Field->getType(), CGM, TSC))
10192       return false;
10193     if (Field->isBitField())
10194       Enc += ')';
10195     Enc += '}';
10196     FE.emplace_back(!Field->getName().empty(), Enc);
10197   }
10198   return true;
10199 }
10200 
10201 /// Appends structure and union types to Enc and adds encoding to cache.
10202 /// Recursively calls appendType (via extractFieldType) for each field.
10203 /// Union types have their fields ordered according to the ABI.
appendRecordType(SmallStringEnc & Enc,const RecordType * RT,const CodeGen::CodeGenModule & CGM,TypeStringCache & TSC,const IdentifierInfo * ID)10204 static bool appendRecordType(SmallStringEnc &Enc, const RecordType *RT,
10205                              const CodeGen::CodeGenModule &CGM,
10206                              TypeStringCache &TSC, const IdentifierInfo *ID) {
10207   // Append the cached TypeString if we have one.
10208   StringRef TypeString = TSC.lookupStr(ID);
10209   if (!TypeString.empty()) {
10210     Enc += TypeString;
10211     return true;
10212   }
10213 
10214   // Start to emit an incomplete TypeString.
10215   size_t Start = Enc.size();
10216   Enc += (RT->isUnionType()? 'u' : 's');
10217   Enc += '(';
10218   if (ID)
10219     Enc += ID->getName();
10220   Enc += "){";
10221 
10222   // We collect all encoded fields and order as necessary.
10223   bool IsRecursive = false;
10224   const RecordDecl *RD = RT->getDecl()->getDefinition();
10225   if (RD && !RD->field_empty()) {
10226     // An incomplete TypeString stub is placed in the cache for this RecordType
10227     // so that recursive calls to this RecordType will use it whilst building a
10228     // complete TypeString for this RecordType.
10229     SmallVector<FieldEncoding, 16> FE;
10230     std::string StubEnc(Enc.substr(Start).str());
10231     StubEnc += '}';  // StubEnc now holds a valid incomplete TypeString.
10232     TSC.addIncomplete(ID, std::move(StubEnc));
10233     if (!extractFieldType(FE, RD, CGM, TSC)) {
10234       (void) TSC.removeIncomplete(ID);
10235       return false;
10236     }
10237     IsRecursive = TSC.removeIncomplete(ID);
10238     // The ABI requires unions to be sorted but not structures.
10239     // See FieldEncoding::operator< for sort algorithm.
10240     if (RT->isUnionType())
10241       llvm::sort(FE);
10242     // We can now complete the TypeString.
10243     unsigned E = FE.size();
10244     for (unsigned I = 0; I != E; ++I) {
10245       if (I)
10246         Enc += ',';
10247       Enc += FE[I].str();
10248     }
10249   }
10250   Enc += '}';
10251   TSC.addIfComplete(ID, Enc.substr(Start), IsRecursive);
10252   return true;
10253 }
10254 
10255 /// Appends enum types to Enc and adds the encoding to the cache.
appendEnumType(SmallStringEnc & Enc,const EnumType * ET,TypeStringCache & TSC,const IdentifierInfo * ID)10256 static bool appendEnumType(SmallStringEnc &Enc, const EnumType *ET,
10257                            TypeStringCache &TSC,
10258                            const IdentifierInfo *ID) {
10259   // Append the cached TypeString if we have one.
10260   StringRef TypeString = TSC.lookupStr(ID);
10261   if (!TypeString.empty()) {
10262     Enc += TypeString;
10263     return true;
10264   }
10265 
10266   size_t Start = Enc.size();
10267   Enc += "e(";
10268   if (ID)
10269     Enc += ID->getName();
10270   Enc += "){";
10271 
10272   // We collect all encoded enumerations and order them alphanumerically.
10273   if (const EnumDecl *ED = ET->getDecl()->getDefinition()) {
10274     SmallVector<FieldEncoding, 16> FE;
10275     for (auto I = ED->enumerator_begin(), E = ED->enumerator_end(); I != E;
10276          ++I) {
10277       SmallStringEnc EnumEnc;
10278       EnumEnc += "m(";
10279       EnumEnc += I->getName();
10280       EnumEnc += "){";
10281       I->getInitVal().toString(EnumEnc);
10282       EnumEnc += '}';
10283       FE.push_back(FieldEncoding(!I->getName().empty(), EnumEnc));
10284     }
10285     llvm::sort(FE);
10286     unsigned E = FE.size();
10287     for (unsigned I = 0; I != E; ++I) {
10288       if (I)
10289         Enc += ',';
10290       Enc += FE[I].str();
10291     }
10292   }
10293   Enc += '}';
10294   TSC.addIfComplete(ID, Enc.substr(Start), false);
10295   return true;
10296 }
10297 
10298 /// Appends type's qualifier to Enc.
10299 /// This is done prior to appending the type's encoding.
appendQualifier(SmallStringEnc & Enc,QualType QT)10300 static void appendQualifier(SmallStringEnc &Enc, QualType QT) {
10301   // Qualifiers are emitted in alphabetical order.
10302   static const char *const Table[]={"","c:","r:","cr:","v:","cv:","rv:","crv:"};
10303   int Lookup = 0;
10304   if (QT.isConstQualified())
10305     Lookup += 1<<0;
10306   if (QT.isRestrictQualified())
10307     Lookup += 1<<1;
10308   if (QT.isVolatileQualified())
10309     Lookup += 1<<2;
10310   Enc += Table[Lookup];
10311 }
10312 
10313 /// Appends built-in types to Enc.
appendBuiltinType(SmallStringEnc & Enc,const BuiltinType * BT)10314 static bool appendBuiltinType(SmallStringEnc &Enc, const BuiltinType *BT) {
10315   const char *EncType;
10316   switch (BT->getKind()) {
10317     case BuiltinType::Void:
10318       EncType = "0";
10319       break;
10320     case BuiltinType::Bool:
10321       EncType = "b";
10322       break;
10323     case BuiltinType::Char_U:
10324       EncType = "uc";
10325       break;
10326     case BuiltinType::UChar:
10327       EncType = "uc";
10328       break;
10329     case BuiltinType::SChar:
10330       EncType = "sc";
10331       break;
10332     case BuiltinType::UShort:
10333       EncType = "us";
10334       break;
10335     case BuiltinType::Short:
10336       EncType = "ss";
10337       break;
10338     case BuiltinType::UInt:
10339       EncType = "ui";
10340       break;
10341     case BuiltinType::Int:
10342       EncType = "si";
10343       break;
10344     case BuiltinType::ULong:
10345       EncType = "ul";
10346       break;
10347     case BuiltinType::Long:
10348       EncType = "sl";
10349       break;
10350     case BuiltinType::ULongLong:
10351       EncType = "ull";
10352       break;
10353     case BuiltinType::LongLong:
10354       EncType = "sll";
10355       break;
10356     case BuiltinType::Float:
10357       EncType = "ft";
10358       break;
10359     case BuiltinType::Double:
10360       EncType = "d";
10361       break;
10362     case BuiltinType::LongDouble:
10363       EncType = "ld";
10364       break;
10365     default:
10366       return false;
10367   }
10368   Enc += EncType;
10369   return true;
10370 }
10371 
10372 /// Appends a pointer encoding to Enc before calling appendType for the pointee.
appendPointerType(SmallStringEnc & Enc,const PointerType * PT,const CodeGen::CodeGenModule & CGM,TypeStringCache & TSC)10373 static bool appendPointerType(SmallStringEnc &Enc, const PointerType *PT,
10374                               const CodeGen::CodeGenModule &CGM,
10375                               TypeStringCache &TSC) {
10376   Enc += "p(";
10377   if (!appendType(Enc, PT->getPointeeType(), CGM, TSC))
10378     return false;
10379   Enc += ')';
10380   return true;
10381 }
10382 
10383 /// Appends array encoding to Enc before calling appendType for the element.
appendArrayType(SmallStringEnc & Enc,QualType QT,const ArrayType * AT,const CodeGen::CodeGenModule & CGM,TypeStringCache & TSC,StringRef NoSizeEnc)10384 static bool appendArrayType(SmallStringEnc &Enc, QualType QT,
10385                             const ArrayType *AT,
10386                             const CodeGen::CodeGenModule &CGM,
10387                             TypeStringCache &TSC, StringRef NoSizeEnc) {
10388   if (AT->getSizeModifier() != ArrayType::Normal)
10389     return false;
10390   Enc += "a(";
10391   if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
10392     CAT->getSize().toStringUnsigned(Enc);
10393   else
10394     Enc += NoSizeEnc; // Global arrays use "*", otherwise it is "".
10395   Enc += ':';
10396   // The Qualifiers should be attached to the type rather than the array.
10397   appendQualifier(Enc, QT);
10398   if (!appendType(Enc, AT->getElementType(), CGM, TSC))
10399     return false;
10400   Enc += ')';
10401   return true;
10402 }
10403 
10404 /// Appends a function encoding to Enc, calling appendType for the return type
10405 /// and the arguments.
appendFunctionType(SmallStringEnc & Enc,const FunctionType * FT,const CodeGen::CodeGenModule & CGM,TypeStringCache & TSC)10406 static bool appendFunctionType(SmallStringEnc &Enc, const FunctionType *FT,
10407                              const CodeGen::CodeGenModule &CGM,
10408                              TypeStringCache &TSC) {
10409   Enc += "f{";
10410   if (!appendType(Enc, FT->getReturnType(), CGM, TSC))
10411     return false;
10412   Enc += "}(";
10413   if (const FunctionProtoType *FPT = FT->getAs<FunctionProtoType>()) {
10414     // N.B. we are only interested in the adjusted param types.
10415     auto I = FPT->param_type_begin();
10416     auto E = FPT->param_type_end();
10417     if (I != E) {
10418       do {
10419         if (!appendType(Enc, *I, CGM, TSC))
10420           return false;
10421         ++I;
10422         if (I != E)
10423           Enc += ',';
10424       } while (I != E);
10425       if (FPT->isVariadic())
10426         Enc += ",va";
10427     } else {
10428       if (FPT->isVariadic())
10429         Enc += "va";
10430       else
10431         Enc += '0';
10432     }
10433   }
10434   Enc += ')';
10435   return true;
10436 }
10437 
10438 /// Handles the type's qualifier before dispatching a call to handle specific
10439 /// type encodings.
appendType(SmallStringEnc & Enc,QualType QType,const CodeGen::CodeGenModule & CGM,TypeStringCache & TSC)10440 static bool appendType(SmallStringEnc &Enc, QualType QType,
10441                        const CodeGen::CodeGenModule &CGM,
10442                        TypeStringCache &TSC) {
10443 
10444   QualType QT = QType.getCanonicalType();
10445 
10446   if (const ArrayType *AT = QT->getAsArrayTypeUnsafe())
10447     // The Qualifiers should be attached to the type rather than the array.
10448     // Thus we don't call appendQualifier() here.
10449     return appendArrayType(Enc, QT, AT, CGM, TSC, "");
10450 
10451   appendQualifier(Enc, QT);
10452 
10453   if (const BuiltinType *BT = QT->getAs<BuiltinType>())
10454     return appendBuiltinType(Enc, BT);
10455 
10456   if (const PointerType *PT = QT->getAs<PointerType>())
10457     return appendPointerType(Enc, PT, CGM, TSC);
10458 
10459   if (const EnumType *ET = QT->getAs<EnumType>())
10460     return appendEnumType(Enc, ET, TSC, QT.getBaseTypeIdentifier());
10461 
10462   if (const RecordType *RT = QT->getAsStructureType())
10463     return appendRecordType(Enc, RT, CGM, TSC, QT.getBaseTypeIdentifier());
10464 
10465   if (const RecordType *RT = QT->getAsUnionType())
10466     return appendRecordType(Enc, RT, CGM, TSC, QT.getBaseTypeIdentifier());
10467 
10468   if (const FunctionType *FT = QT->getAs<FunctionType>())
10469     return appendFunctionType(Enc, FT, CGM, TSC);
10470 
10471   return false;
10472 }
10473 
getTypeString(SmallStringEnc & Enc,const Decl * D,const CodeGen::CodeGenModule & CGM,TypeStringCache & TSC)10474 static bool getTypeString(SmallStringEnc &Enc, const Decl *D,
10475                           const CodeGen::CodeGenModule &CGM,
10476                           TypeStringCache &TSC) {
10477   if (!D)
10478     return false;
10479 
10480   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
10481     if (FD->getLanguageLinkage() != CLanguageLinkage)
10482       return false;
10483     return appendType(Enc, FD->getType(), CGM, TSC);
10484   }
10485 
10486   if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
10487     if (VD->getLanguageLinkage() != CLanguageLinkage)
10488       return false;
10489     QualType QT = VD->getType().getCanonicalType();
10490     if (const ArrayType *AT = QT->getAsArrayTypeUnsafe()) {
10491       // Global ArrayTypes are given a size of '*' if the size is unknown.
10492       // The Qualifiers should be attached to the type rather than the array.
10493       // Thus we don't call appendQualifier() here.
10494       return appendArrayType(Enc, QT, AT, CGM, TSC, "*");
10495     }
10496     return appendType(Enc, QT, CGM, TSC);
10497   }
10498   return false;
10499 }
10500 
10501 //===----------------------------------------------------------------------===//
10502 // RISCV ABI Implementation
10503 //===----------------------------------------------------------------------===//
10504 
10505 namespace {
10506 class RISCVABIInfo : public DefaultABIInfo {
10507 private:
10508   // Size of the integer ('x') registers in bits.
10509   unsigned XLen;
10510   // Size of the floating point ('f') registers in bits. Note that the target
10511   // ISA might have a wider FLen than the selected ABI (e.g. an RV32IF target
10512   // with soft float ABI has FLen==0).
10513   unsigned FLen;
10514   static const int NumArgGPRs = 8;
10515   static const int NumArgFPRs = 8;
10516   bool detectFPCCEligibleStructHelper(QualType Ty, CharUnits CurOff,
10517                                       llvm::Type *&Field1Ty,
10518                                       CharUnits &Field1Off,
10519                                       llvm::Type *&Field2Ty,
10520                                       CharUnits &Field2Off) const;
10521 
10522 public:
RISCVABIInfo(CodeGen::CodeGenTypes & CGT,unsigned XLen,unsigned FLen)10523   RISCVABIInfo(CodeGen::CodeGenTypes &CGT, unsigned XLen, unsigned FLen)
10524       : DefaultABIInfo(CGT), XLen(XLen), FLen(FLen) {}
10525 
10526   // DefaultABIInfo's classifyReturnType and classifyArgumentType are
10527   // non-virtual, but computeInfo is virtual, so we overload it.
10528   void computeInfo(CGFunctionInfo &FI) const override;
10529 
10530   ABIArgInfo classifyArgumentType(QualType Ty, bool IsFixed, int &ArgGPRsLeft,
10531                                   int &ArgFPRsLeft) const;
10532   ABIArgInfo classifyReturnType(QualType RetTy) const;
10533 
10534   Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
10535                     QualType Ty) const override;
10536 
10537   ABIArgInfo extendType(QualType Ty) const;
10538 
10539   bool detectFPCCEligibleStruct(QualType Ty, llvm::Type *&Field1Ty,
10540                                 CharUnits &Field1Off, llvm::Type *&Field2Ty,
10541                                 CharUnits &Field2Off, int &NeededArgGPRs,
10542                                 int &NeededArgFPRs) const;
10543   ABIArgInfo coerceAndExpandFPCCEligibleStruct(llvm::Type *Field1Ty,
10544                                                CharUnits Field1Off,
10545                                                llvm::Type *Field2Ty,
10546                                                CharUnits Field2Off) const;
10547 };
10548 } // end anonymous namespace
10549 
computeInfo(CGFunctionInfo & FI) const10550 void RISCVABIInfo::computeInfo(CGFunctionInfo &FI) const {
10551   QualType RetTy = FI.getReturnType();
10552   if (!getCXXABI().classifyReturnType(FI))
10553     FI.getReturnInfo() = classifyReturnType(RetTy);
10554 
10555   // IsRetIndirect is true if classifyArgumentType indicated the value should
10556   // be passed indirect, or if the type size is a scalar greater than 2*XLen
10557   // and not a complex type with elements <= FLen. e.g. fp128 is passed direct
10558   // in LLVM IR, relying on the backend lowering code to rewrite the argument
10559   // list and pass indirectly on RV32.
10560   bool IsRetIndirect = FI.getReturnInfo().getKind() == ABIArgInfo::Indirect;
10561   if (!IsRetIndirect && RetTy->isScalarType() &&
10562       getContext().getTypeSize(RetTy) > (2 * XLen)) {
10563     if (RetTy->isComplexType() && FLen) {
10564       QualType EltTy = RetTy->castAs<ComplexType>()->getElementType();
10565       IsRetIndirect = getContext().getTypeSize(EltTy) > FLen;
10566     } else {
10567       // This is a normal scalar > 2*XLen, such as fp128 on RV32.
10568       IsRetIndirect = true;
10569     }
10570   }
10571 
10572   // We must track the number of GPRs used in order to conform to the RISC-V
10573   // ABI, as integer scalars passed in registers should have signext/zeroext
10574   // when promoted, but are anyext if passed on the stack. As GPR usage is
10575   // different for variadic arguments, we must also track whether we are
10576   // examining a vararg or not.
10577   int ArgGPRsLeft = IsRetIndirect ? NumArgGPRs - 1 : NumArgGPRs;
10578   int ArgFPRsLeft = FLen ? NumArgFPRs : 0;
10579   int NumFixedArgs = FI.getNumRequiredArgs();
10580 
10581   int ArgNum = 0;
10582   for (auto &ArgInfo : FI.arguments()) {
10583     bool IsFixed = ArgNum < NumFixedArgs;
10584     ArgInfo.info =
10585         classifyArgumentType(ArgInfo.type, IsFixed, ArgGPRsLeft, ArgFPRsLeft);
10586     ArgNum++;
10587   }
10588 }
10589 
10590 // Returns true if the struct is a potential candidate for the floating point
10591 // calling convention. If this function returns true, the caller is
10592 // responsible for checking that if there is only a single field then that
10593 // field is a float.
detectFPCCEligibleStructHelper(QualType Ty,CharUnits CurOff,llvm::Type * & Field1Ty,CharUnits & Field1Off,llvm::Type * & Field2Ty,CharUnits & Field2Off) const10594 bool RISCVABIInfo::detectFPCCEligibleStructHelper(QualType Ty, CharUnits CurOff,
10595                                                   llvm::Type *&Field1Ty,
10596                                                   CharUnits &Field1Off,
10597                                                   llvm::Type *&Field2Ty,
10598                                                   CharUnits &Field2Off) const {
10599   bool IsInt = Ty->isIntegralOrEnumerationType();
10600   bool IsFloat = Ty->isRealFloatingType();
10601 
10602   if (IsInt || IsFloat) {
10603     uint64_t Size = getContext().getTypeSize(Ty);
10604     if (IsInt && Size > XLen)
10605       return false;
10606     // Can't be eligible if larger than the FP registers. Half precision isn't
10607     // currently supported on RISC-V and the ABI hasn't been confirmed, so
10608     // default to the integer ABI in that case.
10609     if (IsFloat && (Size > FLen || Size < 32))
10610       return false;
10611     // Can't be eligible if an integer type was already found (int+int pairs
10612     // are not eligible).
10613     if (IsInt && Field1Ty && Field1Ty->isIntegerTy())
10614       return false;
10615     if (!Field1Ty) {
10616       Field1Ty = CGT.ConvertType(Ty);
10617       Field1Off = CurOff;
10618       return true;
10619     }
10620     if (!Field2Ty) {
10621       Field2Ty = CGT.ConvertType(Ty);
10622       Field2Off = CurOff;
10623       return true;
10624     }
10625     return false;
10626   }
10627 
10628   if (auto CTy = Ty->getAs<ComplexType>()) {
10629     if (Field1Ty)
10630       return false;
10631     QualType EltTy = CTy->getElementType();
10632     if (getContext().getTypeSize(EltTy) > FLen)
10633       return false;
10634     Field1Ty = CGT.ConvertType(EltTy);
10635     Field1Off = CurOff;
10636     Field2Ty = Field1Ty;
10637     Field2Off = Field1Off + getContext().getTypeSizeInChars(EltTy);
10638     return true;
10639   }
10640 
10641   if (const ConstantArrayType *ATy = getContext().getAsConstantArrayType(Ty)) {
10642     uint64_t ArraySize = ATy->getSize().getZExtValue();
10643     QualType EltTy = ATy->getElementType();
10644     CharUnits EltSize = getContext().getTypeSizeInChars(EltTy);
10645     for (uint64_t i = 0; i < ArraySize; ++i) {
10646       bool Ret = detectFPCCEligibleStructHelper(EltTy, CurOff, Field1Ty,
10647                                                 Field1Off, Field2Ty, Field2Off);
10648       if (!Ret)
10649         return false;
10650       CurOff += EltSize;
10651     }
10652     return true;
10653   }
10654 
10655   if (const auto *RTy = Ty->getAs<RecordType>()) {
10656     // Structures with either a non-trivial destructor or a non-trivial
10657     // copy constructor are not eligible for the FP calling convention.
10658     if (getRecordArgABI(Ty, CGT.getCXXABI()))
10659       return false;
10660     if (isEmptyRecord(getContext(), Ty, true))
10661       return true;
10662     const RecordDecl *RD = RTy->getDecl();
10663     // Unions aren't eligible unless they're empty (which is caught above).
10664     if (RD->isUnion())
10665       return false;
10666     int ZeroWidthBitFieldCount = 0;
10667     for (const FieldDecl *FD : RD->fields()) {
10668       const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
10669       uint64_t FieldOffInBits = Layout.getFieldOffset(FD->getFieldIndex());
10670       QualType QTy = FD->getType();
10671       if (FD->isBitField()) {
10672         unsigned BitWidth = FD->getBitWidthValue(getContext());
10673         // Allow a bitfield with a type greater than XLen as long as the
10674         // bitwidth is XLen or less.
10675         if (getContext().getTypeSize(QTy) > XLen && BitWidth <= XLen)
10676           QTy = getContext().getIntTypeForBitwidth(XLen, false);
10677         if (BitWidth == 0) {
10678           ZeroWidthBitFieldCount++;
10679           continue;
10680         }
10681       }
10682 
10683       bool Ret = detectFPCCEligibleStructHelper(
10684           QTy, CurOff + getContext().toCharUnitsFromBits(FieldOffInBits),
10685           Field1Ty, Field1Off, Field2Ty, Field2Off);
10686       if (!Ret)
10687         return false;
10688 
10689       // As a quirk of the ABI, zero-width bitfields aren't ignored for fp+fp
10690       // or int+fp structs, but are ignored for a struct with an fp field and
10691       // any number of zero-width bitfields.
10692       if (Field2Ty && ZeroWidthBitFieldCount > 0)
10693         return false;
10694     }
10695     return Field1Ty != nullptr;
10696   }
10697 
10698   return false;
10699 }
10700 
10701 // Determine if a struct is eligible for passing according to the floating
10702 // point calling convention (i.e., when flattened it contains a single fp
10703 // value, fp+fp, or int+fp of appropriate size). If so, NeededArgFPRs and
10704 // NeededArgGPRs are incremented appropriately.
detectFPCCEligibleStruct(QualType Ty,llvm::Type * & Field1Ty,CharUnits & Field1Off,llvm::Type * & Field2Ty,CharUnits & Field2Off,int & NeededArgGPRs,int & NeededArgFPRs) const10705 bool RISCVABIInfo::detectFPCCEligibleStruct(QualType Ty, llvm::Type *&Field1Ty,
10706                                             CharUnits &Field1Off,
10707                                             llvm::Type *&Field2Ty,
10708                                             CharUnits &Field2Off,
10709                                             int &NeededArgGPRs,
10710                                             int &NeededArgFPRs) const {
10711   Field1Ty = nullptr;
10712   Field2Ty = nullptr;
10713   NeededArgGPRs = 0;
10714   NeededArgFPRs = 0;
10715   bool IsCandidate = detectFPCCEligibleStructHelper(
10716       Ty, CharUnits::Zero(), Field1Ty, Field1Off, Field2Ty, Field2Off);
10717   // Not really a candidate if we have a single int but no float.
10718   if (Field1Ty && !Field2Ty && !Field1Ty->isFloatingPointTy())
10719     return false;
10720   if (!IsCandidate)
10721     return false;
10722   if (Field1Ty && Field1Ty->isFloatingPointTy())
10723     NeededArgFPRs++;
10724   else if (Field1Ty)
10725     NeededArgGPRs++;
10726   if (Field2Ty && Field2Ty->isFloatingPointTy())
10727     NeededArgFPRs++;
10728   else if (Field2Ty)
10729     NeededArgGPRs++;
10730   return true;
10731 }
10732 
10733 // Call getCoerceAndExpand for the two-element flattened struct described by
10734 // Field1Ty, Field1Off, Field2Ty, Field2Off. This method will create an
10735 // appropriate coerceToType and unpaddedCoerceToType.
coerceAndExpandFPCCEligibleStruct(llvm::Type * Field1Ty,CharUnits Field1Off,llvm::Type * Field2Ty,CharUnits Field2Off) const10736 ABIArgInfo RISCVABIInfo::coerceAndExpandFPCCEligibleStruct(
10737     llvm::Type *Field1Ty, CharUnits Field1Off, llvm::Type *Field2Ty,
10738     CharUnits Field2Off) const {
10739   SmallVector<llvm::Type *, 3> CoerceElts;
10740   SmallVector<llvm::Type *, 2> UnpaddedCoerceElts;
10741   if (!Field1Off.isZero())
10742     CoerceElts.push_back(llvm::ArrayType::get(
10743         llvm::Type::getInt8Ty(getVMContext()), Field1Off.getQuantity()));
10744 
10745   CoerceElts.push_back(Field1Ty);
10746   UnpaddedCoerceElts.push_back(Field1Ty);
10747 
10748   if (!Field2Ty) {
10749     return ABIArgInfo::getCoerceAndExpand(
10750         llvm::StructType::get(getVMContext(), CoerceElts, !Field1Off.isZero()),
10751         UnpaddedCoerceElts[0]);
10752   }
10753 
10754   CharUnits Field2Align =
10755       CharUnits::fromQuantity(getDataLayout().getABITypeAlignment(Field2Ty));
10756   CharUnits Field1End = Field1Off +
10757       CharUnits::fromQuantity(getDataLayout().getTypeStoreSize(Field1Ty));
10758   CharUnits Field2OffNoPadNoPack = Field1End.alignTo(Field2Align);
10759 
10760   CharUnits Padding = CharUnits::Zero();
10761   if (Field2Off > Field2OffNoPadNoPack)
10762     Padding = Field2Off - Field2OffNoPadNoPack;
10763   else if (Field2Off != Field2Align && Field2Off > Field1End)
10764     Padding = Field2Off - Field1End;
10765 
10766   bool IsPacked = !Field2Off.isMultipleOf(Field2Align);
10767 
10768   if (!Padding.isZero())
10769     CoerceElts.push_back(llvm::ArrayType::get(
10770         llvm::Type::getInt8Ty(getVMContext()), Padding.getQuantity()));
10771 
10772   CoerceElts.push_back(Field2Ty);
10773   UnpaddedCoerceElts.push_back(Field2Ty);
10774 
10775   auto CoerceToType =
10776       llvm::StructType::get(getVMContext(), CoerceElts, IsPacked);
10777   auto UnpaddedCoerceToType =
10778       llvm::StructType::get(getVMContext(), UnpaddedCoerceElts, IsPacked);
10779 
10780   return ABIArgInfo::getCoerceAndExpand(CoerceToType, UnpaddedCoerceToType);
10781 }
10782 
classifyArgumentType(QualType Ty,bool IsFixed,int & ArgGPRsLeft,int & ArgFPRsLeft) const10783 ABIArgInfo RISCVABIInfo::classifyArgumentType(QualType Ty, bool IsFixed,
10784                                               int &ArgGPRsLeft,
10785                                               int &ArgFPRsLeft) const {
10786   assert(ArgGPRsLeft <= NumArgGPRs && "Arg GPR tracking underflow");
10787   Ty = useFirstFieldIfTransparentUnion(Ty);
10788 
10789   // Structures with either a non-trivial destructor or a non-trivial
10790   // copy constructor are always passed indirectly.
10791   if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
10792     if (ArgGPRsLeft)
10793       ArgGPRsLeft -= 1;
10794     return getNaturalAlignIndirect(Ty, /*ByVal=*/RAA ==
10795                                            CGCXXABI::RAA_DirectInMemory);
10796   }
10797 
10798   // Ignore empty structs/unions.
10799   if (isEmptyRecord(getContext(), Ty, true))
10800     return ABIArgInfo::getIgnore();
10801 
10802   uint64_t Size = getContext().getTypeSize(Ty);
10803 
10804   // Pass floating point values via FPRs if possible.
10805   if (IsFixed && Ty->isFloatingType() && !Ty->isComplexType() &&
10806       FLen >= Size && ArgFPRsLeft) {
10807     ArgFPRsLeft--;
10808     return ABIArgInfo::getDirect();
10809   }
10810 
10811   // Complex types for the hard float ABI must be passed direct rather than
10812   // using CoerceAndExpand.
10813   if (IsFixed && Ty->isComplexType() && FLen && ArgFPRsLeft >= 2) {
10814     QualType EltTy = Ty->castAs<ComplexType>()->getElementType();
10815     if (getContext().getTypeSize(EltTy) <= FLen) {
10816       ArgFPRsLeft -= 2;
10817       return ABIArgInfo::getDirect();
10818     }
10819   }
10820 
10821   if (IsFixed && FLen && Ty->isStructureOrClassType()) {
10822     llvm::Type *Field1Ty = nullptr;
10823     llvm::Type *Field2Ty = nullptr;
10824     CharUnits Field1Off = CharUnits::Zero();
10825     CharUnits Field2Off = CharUnits::Zero();
10826     int NeededArgGPRs = 0;
10827     int NeededArgFPRs = 0;
10828     bool IsCandidate =
10829         detectFPCCEligibleStruct(Ty, Field1Ty, Field1Off, Field2Ty, Field2Off,
10830                                  NeededArgGPRs, NeededArgFPRs);
10831     if (IsCandidate && NeededArgGPRs <= ArgGPRsLeft &&
10832         NeededArgFPRs <= ArgFPRsLeft) {
10833       ArgGPRsLeft -= NeededArgGPRs;
10834       ArgFPRsLeft -= NeededArgFPRs;
10835       return coerceAndExpandFPCCEligibleStruct(Field1Ty, Field1Off, Field2Ty,
10836                                                Field2Off);
10837     }
10838   }
10839 
10840   uint64_t NeededAlign = getContext().getTypeAlign(Ty);
10841   bool MustUseStack = false;
10842   // Determine the number of GPRs needed to pass the current argument
10843   // according to the ABI. 2*XLen-aligned varargs are passed in "aligned"
10844   // register pairs, so may consume 3 registers.
10845   int NeededArgGPRs = 1;
10846   if (!IsFixed && NeededAlign == 2 * XLen)
10847     NeededArgGPRs = 2 + (ArgGPRsLeft % 2);
10848   else if (Size > XLen && Size <= 2 * XLen)
10849     NeededArgGPRs = 2;
10850 
10851   if (NeededArgGPRs > ArgGPRsLeft) {
10852     MustUseStack = true;
10853     NeededArgGPRs = ArgGPRsLeft;
10854   }
10855 
10856   ArgGPRsLeft -= NeededArgGPRs;
10857 
10858   if (!isAggregateTypeForABI(Ty) && !Ty->isVectorType()) {
10859     // Treat an enum type as its underlying type.
10860     if (const EnumType *EnumTy = Ty->getAs<EnumType>())
10861       Ty = EnumTy->getDecl()->getIntegerType();
10862 
10863     // All integral types are promoted to XLen width, unless passed on the
10864     // stack.
10865     if (Size < XLen && Ty->isIntegralOrEnumerationType() && !MustUseStack) {
10866       return extendType(Ty);
10867     }
10868 
10869     if (const auto *EIT = Ty->getAs<ExtIntType>()) {
10870       if (EIT->getNumBits() < XLen && !MustUseStack)
10871         return extendType(Ty);
10872       if (EIT->getNumBits() > 128 ||
10873           (!getContext().getTargetInfo().hasInt128Type() &&
10874            EIT->getNumBits() > 64))
10875         return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
10876     }
10877 
10878     return ABIArgInfo::getDirect();
10879   }
10880 
10881   // Aggregates which are <= 2*XLen will be passed in registers if possible,
10882   // so coerce to integers.
10883   if (Size <= 2 * XLen) {
10884     unsigned Alignment = getContext().getTypeAlign(Ty);
10885 
10886     // Use a single XLen int if possible, 2*XLen if 2*XLen alignment is
10887     // required, and a 2-element XLen array if only XLen alignment is required.
10888     if (Size <= XLen) {
10889       return ABIArgInfo::getDirect(
10890           llvm::IntegerType::get(getVMContext(), XLen));
10891     } else if (Alignment == 2 * XLen) {
10892       return ABIArgInfo::getDirect(
10893           llvm::IntegerType::get(getVMContext(), 2 * XLen));
10894     } else {
10895       return ABIArgInfo::getDirect(llvm::ArrayType::get(
10896           llvm::IntegerType::get(getVMContext(), XLen), 2));
10897     }
10898   }
10899   return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
10900 }
10901 
classifyReturnType(QualType RetTy) const10902 ABIArgInfo RISCVABIInfo::classifyReturnType(QualType RetTy) const {
10903   if (RetTy->isVoidType())
10904     return ABIArgInfo::getIgnore();
10905 
10906   int ArgGPRsLeft = 2;
10907   int ArgFPRsLeft = FLen ? 2 : 0;
10908 
10909   // The rules for return and argument types are the same, so defer to
10910   // classifyArgumentType.
10911   return classifyArgumentType(RetTy, /*IsFixed=*/true, ArgGPRsLeft,
10912                               ArgFPRsLeft);
10913 }
10914 
EmitVAArg(CodeGenFunction & CGF,Address VAListAddr,QualType Ty) const10915 Address RISCVABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
10916                                 QualType Ty) const {
10917   CharUnits SlotSize = CharUnits::fromQuantity(XLen / 8);
10918 
10919   // Empty records are ignored for parameter passing purposes.
10920   if (isEmptyRecord(getContext(), Ty, true)) {
10921     Address Addr(CGF.Builder.CreateLoad(VAListAddr), SlotSize);
10922     Addr = CGF.Builder.CreateElementBitCast(Addr, CGF.ConvertTypeForMem(Ty));
10923     return Addr;
10924   }
10925 
10926   auto TInfo = getContext().getTypeInfoInChars(Ty);
10927 
10928   // Arguments bigger than 2*Xlen bytes are passed indirectly.
10929   bool IsIndirect = TInfo.Width > 2 * SlotSize;
10930 
10931   return emitVoidPtrVAArg(CGF, VAListAddr, Ty, IsIndirect, TInfo,
10932                           SlotSize, /*AllowHigherAlign=*/true);
10933 }
10934 
extendType(QualType Ty) const10935 ABIArgInfo RISCVABIInfo::extendType(QualType Ty) const {
10936   int TySize = getContext().getTypeSize(Ty);
10937   // RV64 ABI requires unsigned 32 bit integers to be sign extended.
10938   if (XLen == 64 && Ty->isUnsignedIntegerOrEnumerationType() && TySize == 32)
10939     return ABIArgInfo::getSignExtend(Ty);
10940   return ABIArgInfo::getExtend(Ty);
10941 }
10942 
10943 namespace {
10944 class RISCVTargetCodeGenInfo : public TargetCodeGenInfo {
10945 public:
RISCVTargetCodeGenInfo(CodeGen::CodeGenTypes & CGT,unsigned XLen,unsigned FLen)10946   RISCVTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, unsigned XLen,
10947                          unsigned FLen)
10948       : TargetCodeGenInfo(std::make_unique<RISCVABIInfo>(CGT, XLen, FLen)) {}
10949 
setTargetAttributes(const Decl * D,llvm::GlobalValue * GV,CodeGen::CodeGenModule & CGM) const10950   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
10951                            CodeGen::CodeGenModule &CGM) const override {
10952     const auto *FD = dyn_cast_or_null<FunctionDecl>(D);
10953     if (!FD) return;
10954 
10955     const auto *Attr = FD->getAttr<RISCVInterruptAttr>();
10956     if (!Attr)
10957       return;
10958 
10959     const char *Kind;
10960     switch (Attr->getInterrupt()) {
10961     case RISCVInterruptAttr::user: Kind = "user"; break;
10962     case RISCVInterruptAttr::supervisor: Kind = "supervisor"; break;
10963     case RISCVInterruptAttr::machine: Kind = "machine"; break;
10964     }
10965 
10966     auto *Fn = cast<llvm::Function>(GV);
10967 
10968     Fn->addFnAttr("interrupt", Kind);
10969   }
10970 };
10971 } // namespace
10972 
10973 //===----------------------------------------------------------------------===//
10974 // VE ABI Implementation.
10975 //
10976 namespace {
10977 class VEABIInfo : public DefaultABIInfo {
10978 public:
VEABIInfo(CodeGenTypes & CGT)10979   VEABIInfo(CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
10980 
10981 private:
10982   ABIArgInfo classifyReturnType(QualType RetTy) const;
10983   ABIArgInfo classifyArgumentType(QualType RetTy) const;
10984   void computeInfo(CGFunctionInfo &FI) const override;
10985 };
10986 } // end anonymous namespace
10987 
classifyReturnType(QualType Ty) const10988 ABIArgInfo VEABIInfo::classifyReturnType(QualType Ty) const {
10989   if (Ty->isAnyComplexType())
10990     return ABIArgInfo::getDirect();
10991   uint64_t Size = getContext().getTypeSize(Ty);
10992   if (Size < 64 && Ty->isIntegerType())
10993     return ABIArgInfo::getExtend(Ty);
10994   return DefaultABIInfo::classifyReturnType(Ty);
10995 }
10996 
classifyArgumentType(QualType Ty) const10997 ABIArgInfo VEABIInfo::classifyArgumentType(QualType Ty) const {
10998   if (Ty->isAnyComplexType())
10999     return ABIArgInfo::getDirect();
11000   uint64_t Size = getContext().getTypeSize(Ty);
11001   if (Size < 64 && Ty->isIntegerType())
11002     return ABIArgInfo::getExtend(Ty);
11003   return DefaultABIInfo::classifyArgumentType(Ty);
11004 }
11005 
computeInfo(CGFunctionInfo & FI) const11006 void VEABIInfo::computeInfo(CGFunctionInfo &FI) const {
11007   FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
11008   for (auto &Arg : FI.arguments())
11009     Arg.info = classifyArgumentType(Arg.type);
11010 }
11011 
11012 namespace {
11013 class VETargetCodeGenInfo : public TargetCodeGenInfo {
11014 public:
VETargetCodeGenInfo(CodeGenTypes & CGT)11015   VETargetCodeGenInfo(CodeGenTypes &CGT)
11016       : TargetCodeGenInfo(std::make_unique<VEABIInfo>(CGT)) {}
11017   // VE ABI requires the arguments of variadic and prototype-less functions
11018   // are passed in both registers and memory.
isNoProtoCallVariadic(const CallArgList & args,const FunctionNoProtoType * fnType) const11019   bool isNoProtoCallVariadic(const CallArgList &args,
11020                              const FunctionNoProtoType *fnType) const override {
11021     return true;
11022   }
11023 };
11024 } // end anonymous namespace
11025 
11026 //===----------------------------------------------------------------------===//
11027 // Driver code
11028 //===----------------------------------------------------------------------===//
11029 
supportsCOMDAT() const11030 bool CodeGenModule::supportsCOMDAT() const {
11031   return getTriple().supportsCOMDAT();
11032 }
11033 
getTargetCodeGenInfo()11034 const TargetCodeGenInfo &CodeGenModule::getTargetCodeGenInfo() {
11035   if (TheTargetCodeGenInfo)
11036     return *TheTargetCodeGenInfo;
11037 
11038   // Helper to set the unique_ptr while still keeping the return value.
11039   auto SetCGInfo = [&](TargetCodeGenInfo *P) -> const TargetCodeGenInfo & {
11040     this->TheTargetCodeGenInfo.reset(P);
11041     return *P;
11042   };
11043 
11044   const llvm::Triple &Triple = getTarget().getTriple();
11045   switch (Triple.getArch()) {
11046   default:
11047     return SetCGInfo(new DefaultTargetCodeGenInfo(Types));
11048 
11049   case llvm::Triple::le32:
11050     return SetCGInfo(new PNaClTargetCodeGenInfo(Types));
11051   case llvm::Triple::m68k:
11052     return SetCGInfo(new M68kTargetCodeGenInfo(Types));
11053   case llvm::Triple::mips:
11054   case llvm::Triple::mipsel:
11055     if (Triple.getOS() == llvm::Triple::NaCl)
11056       return SetCGInfo(new PNaClTargetCodeGenInfo(Types));
11057     return SetCGInfo(new MIPSTargetCodeGenInfo(Types, true));
11058 
11059   case llvm::Triple::mips64:
11060   case llvm::Triple::mips64el:
11061     return SetCGInfo(new MIPSTargetCodeGenInfo(Types, false));
11062 
11063   case llvm::Triple::avr:
11064     return SetCGInfo(new AVRTargetCodeGenInfo(Types));
11065 
11066   case llvm::Triple::aarch64:
11067   case llvm::Triple::aarch64_32:
11068   case llvm::Triple::aarch64_be: {
11069     AArch64ABIInfo::ABIKind Kind = AArch64ABIInfo::AAPCS;
11070     if (getTarget().getABI() == "darwinpcs")
11071       Kind = AArch64ABIInfo::DarwinPCS;
11072     else if (Triple.isOSWindows())
11073       return SetCGInfo(
11074           new WindowsAArch64TargetCodeGenInfo(Types, AArch64ABIInfo::Win64));
11075 
11076     return SetCGInfo(new AArch64TargetCodeGenInfo(Types, Kind));
11077   }
11078 
11079   case llvm::Triple::wasm32:
11080   case llvm::Triple::wasm64: {
11081     WebAssemblyABIInfo::ABIKind Kind = WebAssemblyABIInfo::MVP;
11082     if (getTarget().getABI() == "experimental-mv")
11083       Kind = WebAssemblyABIInfo::ExperimentalMV;
11084     return SetCGInfo(new WebAssemblyTargetCodeGenInfo(Types, Kind));
11085   }
11086 
11087   case llvm::Triple::arm:
11088   case llvm::Triple::armeb:
11089   case llvm::Triple::thumb:
11090   case llvm::Triple::thumbeb: {
11091     if (Triple.getOS() == llvm::Triple::Win32) {
11092       return SetCGInfo(
11093           new WindowsARMTargetCodeGenInfo(Types, ARMABIInfo::AAPCS_VFP));
11094     }
11095 
11096     ARMABIInfo::ABIKind Kind = ARMABIInfo::AAPCS;
11097     StringRef ABIStr = getTarget().getABI();
11098     if (ABIStr == "apcs-gnu")
11099       Kind = ARMABIInfo::APCS;
11100     else if (ABIStr == "aapcs16")
11101       Kind = ARMABIInfo::AAPCS16_VFP;
11102     else if (CodeGenOpts.FloatABI == "hard" ||
11103              (CodeGenOpts.FloatABI != "soft" &&
11104               (Triple.getEnvironment() == llvm::Triple::GNUEABIHF ||
11105                Triple.getEnvironment() == llvm::Triple::MuslEABIHF ||
11106                Triple.getEnvironment() == llvm::Triple::EABIHF)))
11107       Kind = ARMABIInfo::AAPCS_VFP;
11108 
11109     return SetCGInfo(new ARMTargetCodeGenInfo(Types, Kind));
11110   }
11111 
11112   case llvm::Triple::ppc: {
11113     if (Triple.isOSAIX())
11114       return SetCGInfo(new AIXTargetCodeGenInfo(Types, /*Is64Bit*/ false));
11115 
11116     bool IsSoftFloat =
11117         CodeGenOpts.FloatABI == "soft" || getTarget().hasFeature("spe");
11118     bool RetSmallStructInRegABI =
11119         PPC32TargetCodeGenInfo::isStructReturnInRegABI(Triple, CodeGenOpts);
11120     return SetCGInfo(
11121         new PPC32TargetCodeGenInfo(Types, IsSoftFloat, RetSmallStructInRegABI));
11122   }
11123   case llvm::Triple::ppcle: {
11124     bool IsSoftFloat = CodeGenOpts.FloatABI == "soft";
11125     bool RetSmallStructInRegABI =
11126         PPC32TargetCodeGenInfo::isStructReturnInRegABI(Triple, CodeGenOpts);
11127     return SetCGInfo(
11128         new PPC32TargetCodeGenInfo(Types, IsSoftFloat, RetSmallStructInRegABI));
11129   }
11130   case llvm::Triple::ppc64:
11131     if (Triple.isOSAIX())
11132       return SetCGInfo(new AIXTargetCodeGenInfo(Types, /*Is64Bit*/ true));
11133 
11134     if (Triple.isOSBinFormatELF()) {
11135       PPC64_SVR4_ABIInfo::ABIKind Kind = PPC64_SVR4_ABIInfo::ELFv1;
11136       if (getTarget().getABI() == "elfv2")
11137         Kind = PPC64_SVR4_ABIInfo::ELFv2;
11138       bool IsSoftFloat = CodeGenOpts.FloatABI == "soft";
11139 
11140       return SetCGInfo(
11141           new PPC64_SVR4_TargetCodeGenInfo(Types, Kind, IsSoftFloat));
11142     }
11143     return SetCGInfo(new PPC64TargetCodeGenInfo(Types));
11144   case llvm::Triple::ppc64le: {
11145     assert(Triple.isOSBinFormatELF() && "PPC64 LE non-ELF not supported!");
11146     PPC64_SVR4_ABIInfo::ABIKind Kind = PPC64_SVR4_ABIInfo::ELFv2;
11147     if (getTarget().getABI() == "elfv1")
11148       Kind = PPC64_SVR4_ABIInfo::ELFv1;
11149     bool IsSoftFloat = CodeGenOpts.FloatABI == "soft";
11150 
11151     return SetCGInfo(
11152         new PPC64_SVR4_TargetCodeGenInfo(Types, Kind, IsSoftFloat));
11153   }
11154 
11155   case llvm::Triple::nvptx:
11156   case llvm::Triple::nvptx64:
11157     return SetCGInfo(new NVPTXTargetCodeGenInfo(Types));
11158 
11159   case llvm::Triple::msp430:
11160     return SetCGInfo(new MSP430TargetCodeGenInfo(Types));
11161 
11162   case llvm::Triple::riscv32:
11163   case llvm::Triple::riscv64: {
11164     StringRef ABIStr = getTarget().getABI();
11165     unsigned XLen = getTarget().getPointerWidth(0);
11166     unsigned ABIFLen = 0;
11167     if (ABIStr.endswith("f"))
11168       ABIFLen = 32;
11169     else if (ABIStr.endswith("d"))
11170       ABIFLen = 64;
11171     return SetCGInfo(new RISCVTargetCodeGenInfo(Types, XLen, ABIFLen));
11172   }
11173 
11174   case llvm::Triple::systemz: {
11175     bool SoftFloat = CodeGenOpts.FloatABI == "soft";
11176     bool HasVector = !SoftFloat && getTarget().getABI() == "vector";
11177     return SetCGInfo(new SystemZTargetCodeGenInfo(Types, HasVector, SoftFloat));
11178   }
11179 
11180   case llvm::Triple::tce:
11181   case llvm::Triple::tcele:
11182     return SetCGInfo(new TCETargetCodeGenInfo(Types));
11183 
11184   case llvm::Triple::x86: {
11185     bool IsDarwinVectorABI = Triple.isOSDarwin();
11186     bool RetSmallStructInRegABI =
11187         X86_32TargetCodeGenInfo::isStructReturnInRegABI(Triple, CodeGenOpts);
11188     bool IsWin32FloatStructABI = Triple.isOSWindows() && !Triple.isOSCygMing();
11189 
11190     if (Triple.getOS() == llvm::Triple::Win32) {
11191       return SetCGInfo(new WinX86_32TargetCodeGenInfo(
11192           Types, IsDarwinVectorABI, RetSmallStructInRegABI,
11193           IsWin32FloatStructABI, CodeGenOpts.NumRegisterParameters));
11194     } else {
11195       return SetCGInfo(new X86_32TargetCodeGenInfo(
11196           Types, IsDarwinVectorABI, RetSmallStructInRegABI,
11197           IsWin32FloatStructABI, CodeGenOpts.NumRegisterParameters,
11198           CodeGenOpts.FloatABI == "soft"));
11199     }
11200   }
11201 
11202   case llvm::Triple::x86_64: {
11203     StringRef ABI = getTarget().getABI();
11204     X86AVXABILevel AVXLevel =
11205         (ABI == "avx512"
11206              ? X86AVXABILevel::AVX512
11207              : ABI == "avx" ? X86AVXABILevel::AVX : X86AVXABILevel::None);
11208 
11209     switch (Triple.getOS()) {
11210     case llvm::Triple::Win32:
11211       return SetCGInfo(new WinX86_64TargetCodeGenInfo(Types, AVXLevel));
11212     default:
11213       return SetCGInfo(new X86_64TargetCodeGenInfo(Types, AVXLevel));
11214     }
11215   }
11216   case llvm::Triple::hexagon:
11217     return SetCGInfo(new HexagonTargetCodeGenInfo(Types));
11218   case llvm::Triple::lanai:
11219     return SetCGInfo(new LanaiTargetCodeGenInfo(Types));
11220   case llvm::Triple::r600:
11221     return SetCGInfo(new AMDGPUTargetCodeGenInfo(Types));
11222   case llvm::Triple::amdgcn:
11223     return SetCGInfo(new AMDGPUTargetCodeGenInfo(Types));
11224   case llvm::Triple::sparc:
11225     return SetCGInfo(new SparcV8TargetCodeGenInfo(Types));
11226   case llvm::Triple::sparcv9:
11227     return SetCGInfo(new SparcV9TargetCodeGenInfo(Types));
11228   case llvm::Triple::xcore:
11229     return SetCGInfo(new XCoreTargetCodeGenInfo(Types));
11230   case llvm::Triple::arc:
11231     return SetCGInfo(new ARCTargetCodeGenInfo(Types));
11232   case llvm::Triple::spir:
11233   case llvm::Triple::spir64:
11234     return SetCGInfo(new SPIRTargetCodeGenInfo(Types));
11235   case llvm::Triple::ve:
11236     return SetCGInfo(new VETargetCodeGenInfo(Types));
11237   }
11238 }
11239 
11240 /// Create an OpenCL kernel for an enqueued block.
11241 ///
11242 /// The kernel has the same function type as the block invoke function. Its
11243 /// name is the name of the block invoke function postfixed with "_kernel".
11244 /// It simply calls the block invoke function then returns.
11245 llvm::Function *
createEnqueuedBlockKernel(CodeGenFunction & CGF,llvm::Function * Invoke,llvm::Value * BlockLiteral) const11246 TargetCodeGenInfo::createEnqueuedBlockKernel(CodeGenFunction &CGF,
11247                                              llvm::Function *Invoke,
11248                                              llvm::Value *BlockLiteral) const {
11249   auto *InvokeFT = Invoke->getFunctionType();
11250   llvm::SmallVector<llvm::Type *, 2> ArgTys;
11251   for (auto &P : InvokeFT->params())
11252     ArgTys.push_back(P);
11253   auto &C = CGF.getLLVMContext();
11254   std::string Name = Invoke->getName().str() + "_kernel";
11255   auto *FT = llvm::FunctionType::get(llvm::Type::getVoidTy(C), ArgTys, false);
11256   auto *F = llvm::Function::Create(FT, llvm::GlobalValue::InternalLinkage, Name,
11257                                    &CGF.CGM.getModule());
11258   auto IP = CGF.Builder.saveIP();
11259   auto *BB = llvm::BasicBlock::Create(C, "entry", F);
11260   auto &Builder = CGF.Builder;
11261   Builder.SetInsertPoint(BB);
11262   llvm::SmallVector<llvm::Value *, 2> Args;
11263   for (auto &A : F->args())
11264     Args.push_back(&A);
11265   llvm::CallInst *call = Builder.CreateCall(Invoke, Args);
11266   call->setCallingConv(Invoke->getCallingConv());
11267   Builder.CreateRetVoid();
11268   Builder.restoreIP(IP);
11269   return F;
11270 }
11271 
11272 /// Create an OpenCL kernel for an enqueued block.
11273 ///
11274 /// The type of the first argument (the block literal) is the struct type
11275 /// of the block literal instead of a pointer type. The first argument
11276 /// (block literal) is passed directly by value to the kernel. The kernel
11277 /// allocates the same type of struct on stack and stores the block literal
11278 /// to it and passes its pointer to the block invoke function. The kernel
11279 /// has "enqueued-block" function attribute and kernel argument metadata.
createEnqueuedBlockKernel(CodeGenFunction & CGF,llvm::Function * Invoke,llvm::Value * BlockLiteral) const11280 llvm::Function *AMDGPUTargetCodeGenInfo::createEnqueuedBlockKernel(
11281     CodeGenFunction &CGF, llvm::Function *Invoke,
11282     llvm::Value *BlockLiteral) const {
11283   auto &Builder = CGF.Builder;
11284   auto &C = CGF.getLLVMContext();
11285 
11286   auto *BlockTy = BlockLiteral->getType()->getPointerElementType();
11287   auto *InvokeFT = Invoke->getFunctionType();
11288   llvm::SmallVector<llvm::Type *, 2> ArgTys;
11289   llvm::SmallVector<llvm::Metadata *, 8> AddressQuals;
11290   llvm::SmallVector<llvm::Metadata *, 8> AccessQuals;
11291   llvm::SmallVector<llvm::Metadata *, 8> ArgTypeNames;
11292   llvm::SmallVector<llvm::Metadata *, 8> ArgBaseTypeNames;
11293   llvm::SmallVector<llvm::Metadata *, 8> ArgTypeQuals;
11294   llvm::SmallVector<llvm::Metadata *, 8> ArgNames;
11295 
11296   ArgTys.push_back(BlockTy);
11297   ArgTypeNames.push_back(llvm::MDString::get(C, "__block_literal"));
11298   AddressQuals.push_back(llvm::ConstantAsMetadata::get(Builder.getInt32(0)));
11299   ArgBaseTypeNames.push_back(llvm::MDString::get(C, "__block_literal"));
11300   ArgTypeQuals.push_back(llvm::MDString::get(C, ""));
11301   AccessQuals.push_back(llvm::MDString::get(C, "none"));
11302   ArgNames.push_back(llvm::MDString::get(C, "block_literal"));
11303   for (unsigned I = 1, E = InvokeFT->getNumParams(); I < E; ++I) {
11304     ArgTys.push_back(InvokeFT->getParamType(I));
11305     ArgTypeNames.push_back(llvm::MDString::get(C, "void*"));
11306     AddressQuals.push_back(llvm::ConstantAsMetadata::get(Builder.getInt32(3)));
11307     AccessQuals.push_back(llvm::MDString::get(C, "none"));
11308     ArgBaseTypeNames.push_back(llvm::MDString::get(C, "void*"));
11309     ArgTypeQuals.push_back(llvm::MDString::get(C, ""));
11310     ArgNames.push_back(
11311         llvm::MDString::get(C, (Twine("local_arg") + Twine(I)).str()));
11312   }
11313   std::string Name = Invoke->getName().str() + "_kernel";
11314   auto *FT = llvm::FunctionType::get(llvm::Type::getVoidTy(C), ArgTys, false);
11315   auto *F = llvm::Function::Create(FT, llvm::GlobalValue::InternalLinkage, Name,
11316                                    &CGF.CGM.getModule());
11317   F->addFnAttr("enqueued-block");
11318   auto IP = CGF.Builder.saveIP();
11319   auto *BB = llvm::BasicBlock::Create(C, "entry", F);
11320   Builder.SetInsertPoint(BB);
11321   const auto BlockAlign = CGF.CGM.getDataLayout().getPrefTypeAlign(BlockTy);
11322   auto *BlockPtr = Builder.CreateAlloca(BlockTy, nullptr);
11323   BlockPtr->setAlignment(BlockAlign);
11324   Builder.CreateAlignedStore(F->arg_begin(), BlockPtr, BlockAlign);
11325   auto *Cast = Builder.CreatePointerCast(BlockPtr, InvokeFT->getParamType(0));
11326   llvm::SmallVector<llvm::Value *, 2> Args;
11327   Args.push_back(Cast);
11328   for (auto I = F->arg_begin() + 1, E = F->arg_end(); I != E; ++I)
11329     Args.push_back(I);
11330   llvm::CallInst *call = Builder.CreateCall(Invoke, Args);
11331   call->setCallingConv(Invoke->getCallingConv());
11332   Builder.CreateRetVoid();
11333   Builder.restoreIP(IP);
11334 
11335   F->setMetadata("kernel_arg_addr_space", llvm::MDNode::get(C, AddressQuals));
11336   F->setMetadata("kernel_arg_access_qual", llvm::MDNode::get(C, AccessQuals));
11337   F->setMetadata("kernel_arg_type", llvm::MDNode::get(C, ArgTypeNames));
11338   F->setMetadata("kernel_arg_base_type",
11339                  llvm::MDNode::get(C, ArgBaseTypeNames));
11340   F->setMetadata("kernel_arg_type_qual", llvm::MDNode::get(C, ArgTypeQuals));
11341   if (CGF.CGM.getCodeGenOpts().EmitOpenCLArgMetadata)
11342     F->setMetadata("kernel_arg_name", llvm::MDNode::get(C, ArgNames));
11343 
11344   return F;
11345 }
11346