1 //===--- CodeGenModule.cpp - Emit LLVM Code from ASTs for a Module --------===//
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 // This coordinates the per-module state used while generating code.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "CodeGenModule.h"
14 #include "ABIInfo.h"
15 #include "CGBlocks.h"
16 #include "CGCUDARuntime.h"
17 #include "CGCXXABI.h"
18 #include "CGCall.h"
19 #include "CGDebugInfo.h"
20 #include "CGHLSLRuntime.h"
21 #include "CGObjCRuntime.h"
22 #include "CGOpenCLRuntime.h"
23 #include "CGOpenMPRuntime.h"
24 #include "CGOpenMPRuntimeGPU.h"
25 #include "CodeGenFunction.h"
26 #include "CodeGenPGO.h"
27 #include "ConstantEmitter.h"
28 #include "CoverageMappingGen.h"
29 #include "TargetInfo.h"
30 #include "clang/AST/ASTContext.h"
31 #include "clang/AST/CharUnits.h"
32 #include "clang/AST/DeclCXX.h"
33 #include "clang/AST/DeclObjC.h"
34 #include "clang/AST/DeclTemplate.h"
35 #include "clang/AST/Mangle.h"
36 #include "clang/AST/RecursiveASTVisitor.h"
37 #include "clang/AST/StmtVisitor.h"
38 #include "clang/Basic/Builtins.h"
39 #include "clang/Basic/CharInfo.h"
40 #include "clang/Basic/CodeGenOptions.h"
41 #include "clang/Basic/Diagnostic.h"
42 #include "clang/Basic/FileManager.h"
43 #include "clang/Basic/Module.h"
44 #include "clang/Basic/SourceManager.h"
45 #include "clang/Basic/TargetInfo.h"
46 #include "clang/Basic/Version.h"
47 #include "clang/CodeGen/BackendUtil.h"
48 #include "clang/CodeGen/ConstantInitBuilder.h"
49 #include "clang/Frontend/FrontendDiagnostic.h"
50 #include "llvm/ADT/STLExtras.h"
51 #include "llvm/ADT/StringExtras.h"
52 #include "llvm/ADT/StringSwitch.h"
53 #include "llvm/ADT/Triple.h"
54 #include "llvm/Analysis/TargetLibraryInfo.h"
55 #include "llvm/Frontend/OpenMP/OMPIRBuilder.h"
56 #include "llvm/IR/CallingConv.h"
57 #include "llvm/IR/DataLayout.h"
58 #include "llvm/IR/Intrinsics.h"
59 #include "llvm/IR/LLVMContext.h"
60 #include "llvm/IR/Module.h"
61 #include "llvm/IR/ProfileSummary.h"
62 #include "llvm/ProfileData/InstrProfReader.h"
63 #include "llvm/ProfileData/SampleProf.h"
64 #include "llvm/Support/CRC.h"
65 #include "llvm/Support/CodeGen.h"
66 #include "llvm/Support/CommandLine.h"
67 #include "llvm/Support/ConvertUTF.h"
68 #include "llvm/Support/ErrorHandling.h"
69 #include "llvm/Support/TimeProfiler.h"
70 #include "llvm/Support/X86TargetParser.h"
71 #include "llvm/Support/xxhash.h"
72 #include <optional>
73
74 using namespace clang;
75 using namespace CodeGen;
76
77 static llvm::cl::opt<bool> LimitedCoverage(
78 "limited-coverage-experimental", llvm::cl::Hidden,
79 llvm::cl::desc("Emit limited coverage mapping information (experimental)"));
80
81 static const char AnnotationSection[] = "llvm.metadata";
82
createCXXABI(CodeGenModule & CGM)83 static CGCXXABI *createCXXABI(CodeGenModule &CGM) {
84 switch (CGM.getContext().getCXXABIKind()) {
85 case TargetCXXABI::AppleARM64:
86 case TargetCXXABI::Fuchsia:
87 case TargetCXXABI::GenericAArch64:
88 case TargetCXXABI::GenericARM:
89 case TargetCXXABI::iOS:
90 case TargetCXXABI::WatchOS:
91 case TargetCXXABI::GenericMIPS:
92 case TargetCXXABI::GenericItanium:
93 case TargetCXXABI::WebAssembly:
94 case TargetCXXABI::XL:
95 return CreateItaniumCXXABI(CGM);
96 case TargetCXXABI::Microsoft:
97 return CreateMicrosoftCXXABI(CGM);
98 }
99
100 llvm_unreachable("invalid C++ ABI kind");
101 }
102
CodeGenModule(ASTContext & C,IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS,const HeaderSearchOptions & HSO,const PreprocessorOptions & PPO,const CodeGenOptions & CGO,llvm::Module & M,DiagnosticsEngine & diags,CoverageSourceInfo * CoverageInfo)103 CodeGenModule::CodeGenModule(ASTContext &C,
104 IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS,
105 const HeaderSearchOptions &HSO,
106 const PreprocessorOptions &PPO,
107 const CodeGenOptions &CGO, llvm::Module &M,
108 DiagnosticsEngine &diags,
109 CoverageSourceInfo *CoverageInfo)
110 : Context(C), LangOpts(C.getLangOpts()), FS(std::move(FS)),
111 HeaderSearchOpts(HSO), PreprocessorOpts(PPO), CodeGenOpts(CGO),
112 TheModule(M), Diags(diags), Target(C.getTargetInfo()),
113 ABI(createCXXABI(*this)), VMContext(M.getContext()), Types(*this),
114 VTables(*this), SanitizerMD(new SanitizerMetadata(*this)) {
115
116 // Initialize the type cache.
117 llvm::LLVMContext &LLVMContext = M.getContext();
118 VoidTy = llvm::Type::getVoidTy(LLVMContext);
119 Int8Ty = llvm::Type::getInt8Ty(LLVMContext);
120 Int16Ty = llvm::Type::getInt16Ty(LLVMContext);
121 Int32Ty = llvm::Type::getInt32Ty(LLVMContext);
122 Int64Ty = llvm::Type::getInt64Ty(LLVMContext);
123 HalfTy = llvm::Type::getHalfTy(LLVMContext);
124 BFloatTy = llvm::Type::getBFloatTy(LLVMContext);
125 FloatTy = llvm::Type::getFloatTy(LLVMContext);
126 DoubleTy = llvm::Type::getDoubleTy(LLVMContext);
127 PointerWidthInBits = C.getTargetInfo().getPointerWidth(LangAS::Default);
128 PointerAlignInBytes =
129 C.toCharUnitsFromBits(C.getTargetInfo().getPointerAlign(LangAS::Default))
130 .getQuantity();
131 SizeSizeInBytes =
132 C.toCharUnitsFromBits(C.getTargetInfo().getMaxPointerWidth()).getQuantity();
133 IntAlignInBytes =
134 C.toCharUnitsFromBits(C.getTargetInfo().getIntAlign()).getQuantity();
135 CharTy =
136 llvm::IntegerType::get(LLVMContext, C.getTargetInfo().getCharWidth());
137 IntTy = llvm::IntegerType::get(LLVMContext, C.getTargetInfo().getIntWidth());
138 IntPtrTy = llvm::IntegerType::get(LLVMContext,
139 C.getTargetInfo().getMaxPointerWidth());
140 Int8PtrTy = Int8Ty->getPointerTo(0);
141 Int8PtrPtrTy = Int8PtrTy->getPointerTo(0);
142 const llvm::DataLayout &DL = M.getDataLayout();
143 AllocaInt8PtrTy = Int8Ty->getPointerTo(DL.getAllocaAddrSpace());
144 GlobalsInt8PtrTy = Int8Ty->getPointerTo(DL.getDefaultGlobalsAddressSpace());
145 ConstGlobalsPtrTy = Int8Ty->getPointerTo(
146 C.getTargetAddressSpace(GetGlobalConstantAddressSpace()));
147 ASTAllocaAddressSpace = getTargetCodeGenInfo().getASTAllocaAddressSpace();
148
149 // Build C++20 Module initializers.
150 // TODO: Add Microsoft here once we know the mangling required for the
151 // initializers.
152 CXX20ModuleInits =
153 LangOpts.CPlusPlusModules && getCXXABI().getMangleContext().getKind() ==
154 ItaniumMangleContext::MK_Itanium;
155
156 RuntimeCC = getTargetCodeGenInfo().getABIInfo().getRuntimeCC();
157
158 if (LangOpts.ObjC)
159 createObjCRuntime();
160 if (LangOpts.OpenCL)
161 createOpenCLRuntime();
162 if (LangOpts.OpenMP)
163 createOpenMPRuntime();
164 if (LangOpts.CUDA)
165 createCUDARuntime();
166 if (LangOpts.HLSL)
167 createHLSLRuntime();
168
169 // Enable TBAA unless it's suppressed. ThreadSanitizer needs TBAA even at O0.
170 if (LangOpts.Sanitize.has(SanitizerKind::Thread) ||
171 (!CodeGenOpts.RelaxedAliasing && CodeGenOpts.OptimizationLevel > 0))
172 TBAA.reset(new CodeGenTBAA(Context, TheModule, CodeGenOpts, getLangOpts(),
173 getCXXABI().getMangleContext()));
174
175 // If debug info or coverage generation is enabled, create the CGDebugInfo
176 // object.
177 if (CodeGenOpts.getDebugInfo() != codegenoptions::NoDebugInfo ||
178 CodeGenOpts.EmitGcovArcs || CodeGenOpts.EmitGcovNotes)
179 DebugInfo.reset(new CGDebugInfo(*this));
180
181 Block.GlobalUniqueCount = 0;
182
183 if (C.getLangOpts().ObjC)
184 ObjCData.reset(new ObjCEntrypoints());
185
186 if (CodeGenOpts.hasProfileClangUse()) {
187 auto ReaderOrErr = llvm::IndexedInstrProfReader::create(
188 CodeGenOpts.ProfileInstrumentUsePath, CodeGenOpts.ProfileRemappingFile);
189 // We're checking for profile read errors in CompilerInvocation, so if
190 // there was an error it should've already been caught. If it hasn't been
191 // somehow, trip an assertion.
192 assert(ReaderOrErr);
193 PGOReader = std::move(ReaderOrErr.get());
194 }
195
196 // If coverage mapping generation is enabled, create the
197 // CoverageMappingModuleGen object.
198 if (CodeGenOpts.CoverageMapping)
199 CoverageMapping.reset(new CoverageMappingModuleGen(*this, *CoverageInfo));
200
201 // Generate the module name hash here if needed.
202 if (CodeGenOpts.UniqueInternalLinkageNames &&
203 !getModule().getSourceFileName().empty()) {
204 std::string Path = getModule().getSourceFileName();
205 // Check if a path substitution is needed from the MacroPrefixMap.
206 for (const auto &Entry : LangOpts.MacroPrefixMap)
207 if (Path.rfind(Entry.first, 0) != std::string::npos) {
208 Path = Entry.second + Path.substr(Entry.first.size());
209 break;
210 }
211 ModuleNameHash = llvm::getUniqueInternalLinkagePostfix(Path);
212 }
213 }
214
~CodeGenModule()215 CodeGenModule::~CodeGenModule() {}
216
createObjCRuntime()217 void CodeGenModule::createObjCRuntime() {
218 // This is just isGNUFamily(), but we want to force implementors of
219 // new ABIs to decide how best to do this.
220 switch (LangOpts.ObjCRuntime.getKind()) {
221 case ObjCRuntime::GNUstep:
222 case ObjCRuntime::GCC:
223 case ObjCRuntime::ObjFW:
224 ObjCRuntime.reset(CreateGNUObjCRuntime(*this));
225 return;
226
227 case ObjCRuntime::FragileMacOSX:
228 case ObjCRuntime::MacOSX:
229 case ObjCRuntime::iOS:
230 case ObjCRuntime::WatchOS:
231 ObjCRuntime.reset(CreateMacObjCRuntime(*this));
232 return;
233 }
234 llvm_unreachable("bad runtime kind");
235 }
236
createOpenCLRuntime()237 void CodeGenModule::createOpenCLRuntime() {
238 OpenCLRuntime.reset(new CGOpenCLRuntime(*this));
239 }
240
createOpenMPRuntime()241 void CodeGenModule::createOpenMPRuntime() {
242 // Select a specialized code generation class based on the target, if any.
243 // If it does not exist use the default implementation.
244 switch (getTriple().getArch()) {
245 case llvm::Triple::nvptx:
246 case llvm::Triple::nvptx64:
247 case llvm::Triple::amdgcn:
248 assert(getLangOpts().OpenMPIsDevice &&
249 "OpenMP AMDGPU/NVPTX is only prepared to deal with device code.");
250 OpenMPRuntime.reset(new CGOpenMPRuntimeGPU(*this));
251 break;
252 default:
253 if (LangOpts.OpenMPSimd)
254 OpenMPRuntime.reset(new CGOpenMPSIMDRuntime(*this));
255 else
256 OpenMPRuntime.reset(new CGOpenMPRuntime(*this));
257 break;
258 }
259 }
260
createCUDARuntime()261 void CodeGenModule::createCUDARuntime() {
262 CUDARuntime.reset(CreateNVCUDARuntime(*this));
263 }
264
createHLSLRuntime()265 void CodeGenModule::createHLSLRuntime() {
266 HLSLRuntime.reset(new CGHLSLRuntime(*this));
267 }
268
addReplacement(StringRef Name,llvm::Constant * C)269 void CodeGenModule::addReplacement(StringRef Name, llvm::Constant *C) {
270 Replacements[Name] = C;
271 }
272
applyReplacements()273 void CodeGenModule::applyReplacements() {
274 for (auto &I : Replacements) {
275 StringRef MangledName = I.first();
276 llvm::Constant *Replacement = I.second;
277 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
278 if (!Entry)
279 continue;
280 auto *OldF = cast<llvm::Function>(Entry);
281 auto *NewF = dyn_cast<llvm::Function>(Replacement);
282 if (!NewF) {
283 if (auto *Alias = dyn_cast<llvm::GlobalAlias>(Replacement)) {
284 NewF = dyn_cast<llvm::Function>(Alias->getAliasee());
285 } else {
286 auto *CE = cast<llvm::ConstantExpr>(Replacement);
287 assert(CE->getOpcode() == llvm::Instruction::BitCast ||
288 CE->getOpcode() == llvm::Instruction::GetElementPtr);
289 NewF = dyn_cast<llvm::Function>(CE->getOperand(0));
290 }
291 }
292
293 // Replace old with new, but keep the old order.
294 OldF->replaceAllUsesWith(Replacement);
295 if (NewF) {
296 NewF->removeFromParent();
297 OldF->getParent()->getFunctionList().insertAfter(OldF->getIterator(),
298 NewF);
299 }
300 OldF->eraseFromParent();
301 }
302 }
303
addGlobalValReplacement(llvm::GlobalValue * GV,llvm::Constant * C)304 void CodeGenModule::addGlobalValReplacement(llvm::GlobalValue *GV, llvm::Constant *C) {
305 GlobalValReplacements.push_back(std::make_pair(GV, C));
306 }
307
applyGlobalValReplacements()308 void CodeGenModule::applyGlobalValReplacements() {
309 for (auto &I : GlobalValReplacements) {
310 llvm::GlobalValue *GV = I.first;
311 llvm::Constant *C = I.second;
312
313 GV->replaceAllUsesWith(C);
314 GV->eraseFromParent();
315 }
316 }
317
318 // This is only used in aliases that we created and we know they have a
319 // linear structure.
getAliasedGlobal(const llvm::GlobalValue * GV)320 static const llvm::GlobalValue *getAliasedGlobal(const llvm::GlobalValue *GV) {
321 const llvm::Constant *C;
322 if (auto *GA = dyn_cast<llvm::GlobalAlias>(GV))
323 C = GA->getAliasee();
324 else if (auto *GI = dyn_cast<llvm::GlobalIFunc>(GV))
325 C = GI->getResolver();
326 else
327 return GV;
328
329 const auto *AliaseeGV = dyn_cast<llvm::GlobalValue>(C->stripPointerCasts());
330 if (!AliaseeGV)
331 return nullptr;
332
333 const llvm::GlobalValue *FinalGV = AliaseeGV->getAliaseeObject();
334 if (FinalGV == GV)
335 return nullptr;
336
337 return FinalGV;
338 }
339
checkAliasedGlobal(DiagnosticsEngine & Diags,SourceLocation Location,bool IsIFunc,const llvm::GlobalValue * Alias,const llvm::GlobalValue * & GV)340 static bool checkAliasedGlobal(DiagnosticsEngine &Diags,
341 SourceLocation Location, bool IsIFunc,
342 const llvm::GlobalValue *Alias,
343 const llvm::GlobalValue *&GV) {
344 GV = getAliasedGlobal(Alias);
345 if (!GV) {
346 Diags.Report(Location, diag::err_cyclic_alias) << IsIFunc;
347 return false;
348 }
349
350 if (GV->isDeclaration()) {
351 Diags.Report(Location, diag::err_alias_to_undefined) << IsIFunc << IsIFunc;
352 return false;
353 }
354
355 if (IsIFunc) {
356 // Check resolver function type.
357 const auto *F = dyn_cast<llvm::Function>(GV);
358 if (!F) {
359 Diags.Report(Location, diag::err_alias_to_undefined)
360 << IsIFunc << IsIFunc;
361 return false;
362 }
363
364 llvm::FunctionType *FTy = F->getFunctionType();
365 if (!FTy->getReturnType()->isPointerTy()) {
366 Diags.Report(Location, diag::err_ifunc_resolver_return);
367 return false;
368 }
369 }
370
371 return true;
372 }
373
checkAliases()374 void CodeGenModule::checkAliases() {
375 // Check if the constructed aliases are well formed. It is really unfortunate
376 // that we have to do this in CodeGen, but we only construct mangled names
377 // and aliases during codegen.
378 bool Error = false;
379 DiagnosticsEngine &Diags = getDiags();
380 for (const GlobalDecl &GD : Aliases) {
381 const auto *D = cast<ValueDecl>(GD.getDecl());
382 SourceLocation Location;
383 bool IsIFunc = D->hasAttr<IFuncAttr>();
384 if (const Attr *A = D->getDefiningAttr())
385 Location = A->getLocation();
386 else
387 llvm_unreachable("Not an alias or ifunc?");
388
389 StringRef MangledName = getMangledName(GD);
390 llvm::GlobalValue *Alias = GetGlobalValue(MangledName);
391 const llvm::GlobalValue *GV = nullptr;
392 if (!checkAliasedGlobal(Diags, Location, IsIFunc, Alias, GV)) {
393 Error = true;
394 continue;
395 }
396
397 llvm::Constant *Aliasee =
398 IsIFunc ? cast<llvm::GlobalIFunc>(Alias)->getResolver()
399 : cast<llvm::GlobalAlias>(Alias)->getAliasee();
400
401 llvm::GlobalValue *AliaseeGV;
402 if (auto CE = dyn_cast<llvm::ConstantExpr>(Aliasee))
403 AliaseeGV = cast<llvm::GlobalValue>(CE->getOperand(0));
404 else
405 AliaseeGV = cast<llvm::GlobalValue>(Aliasee);
406
407 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) {
408 StringRef AliasSection = SA->getName();
409 if (AliasSection != AliaseeGV->getSection())
410 Diags.Report(SA->getLocation(), diag::warn_alias_with_section)
411 << AliasSection << IsIFunc << IsIFunc;
412 }
413
414 // We have to handle alias to weak aliases in here. LLVM itself disallows
415 // this since the object semantics would not match the IL one. For
416 // compatibility with gcc we implement it by just pointing the alias
417 // to its aliasee's aliasee. We also warn, since the user is probably
418 // expecting the link to be weak.
419 if (auto *GA = dyn_cast<llvm::GlobalAlias>(AliaseeGV)) {
420 if (GA->isInterposable()) {
421 Diags.Report(Location, diag::warn_alias_to_weak_alias)
422 << GV->getName() << GA->getName() << IsIFunc;
423 Aliasee = llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(
424 GA->getAliasee(), Alias->getType());
425
426 if (IsIFunc)
427 cast<llvm::GlobalIFunc>(Alias)->setResolver(Aliasee);
428 else
429 cast<llvm::GlobalAlias>(Alias)->setAliasee(Aliasee);
430 }
431 }
432 }
433 if (!Error)
434 return;
435
436 for (const GlobalDecl &GD : Aliases) {
437 StringRef MangledName = getMangledName(GD);
438 llvm::GlobalValue *Alias = GetGlobalValue(MangledName);
439 Alias->replaceAllUsesWith(llvm::UndefValue::get(Alias->getType()));
440 Alias->eraseFromParent();
441 }
442 }
443
clear()444 void CodeGenModule::clear() {
445 DeferredDeclsToEmit.clear();
446 EmittedDeferredDecls.clear();
447 if (OpenMPRuntime)
448 OpenMPRuntime->clear();
449 }
450
reportDiagnostics(DiagnosticsEngine & Diags,StringRef MainFile)451 void InstrProfStats::reportDiagnostics(DiagnosticsEngine &Diags,
452 StringRef MainFile) {
453 if (!hasDiagnostics())
454 return;
455 if (VisitedInMainFile > 0 && VisitedInMainFile == MissingInMainFile) {
456 if (MainFile.empty())
457 MainFile = "<stdin>";
458 Diags.Report(diag::warn_profile_data_unprofiled) << MainFile;
459 } else {
460 if (Mismatched > 0)
461 Diags.Report(diag::warn_profile_data_out_of_date) << Visited << Mismatched;
462
463 if (Missing > 0)
464 Diags.Report(diag::warn_profile_data_missing) << Visited << Missing;
465 }
466 }
467
setVisibilityFromDLLStorageClass(const clang::LangOptions & LO,llvm::Module & M)468 static void setVisibilityFromDLLStorageClass(const clang::LangOptions &LO,
469 llvm::Module &M) {
470 if (!LO.VisibilityFromDLLStorageClass)
471 return;
472
473 llvm::GlobalValue::VisibilityTypes DLLExportVisibility =
474 CodeGenModule::GetLLVMVisibility(LO.getDLLExportVisibility());
475 llvm::GlobalValue::VisibilityTypes NoDLLStorageClassVisibility =
476 CodeGenModule::GetLLVMVisibility(LO.getNoDLLStorageClassVisibility());
477 llvm::GlobalValue::VisibilityTypes ExternDeclDLLImportVisibility =
478 CodeGenModule::GetLLVMVisibility(LO.getExternDeclDLLImportVisibility());
479 llvm::GlobalValue::VisibilityTypes ExternDeclNoDLLStorageClassVisibility =
480 CodeGenModule::GetLLVMVisibility(
481 LO.getExternDeclNoDLLStorageClassVisibility());
482
483 for (llvm::GlobalValue &GV : M.global_values()) {
484 if (GV.hasAppendingLinkage() || GV.hasLocalLinkage())
485 continue;
486
487 // Reset DSO locality before setting the visibility. This removes
488 // any effects that visibility options and annotations may have
489 // had on the DSO locality. Setting the visibility will implicitly set
490 // appropriate globals to DSO Local; however, this will be pessimistic
491 // w.r.t. to the normal compiler IRGen.
492 GV.setDSOLocal(false);
493
494 if (GV.isDeclarationForLinker()) {
495 GV.setVisibility(GV.getDLLStorageClass() ==
496 llvm::GlobalValue::DLLImportStorageClass
497 ? ExternDeclDLLImportVisibility
498 : ExternDeclNoDLLStorageClassVisibility);
499 } else {
500 GV.setVisibility(GV.getDLLStorageClass() ==
501 llvm::GlobalValue::DLLExportStorageClass
502 ? DLLExportVisibility
503 : NoDLLStorageClassVisibility);
504 }
505
506 GV.setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
507 }
508 }
509
Release()510 void CodeGenModule::Release() {
511 Module *Primary = getContext().getModuleForCodeGen();
512 if (CXX20ModuleInits && Primary && !Primary->isHeaderLikeModule())
513 EmitModuleInitializers(Primary);
514 EmitDeferred();
515 DeferredDecls.insert(EmittedDeferredDecls.begin(),
516 EmittedDeferredDecls.end());
517 EmittedDeferredDecls.clear();
518 EmitVTablesOpportunistically();
519 applyGlobalValReplacements();
520 applyReplacements();
521 emitMultiVersionFunctions();
522
523 if (Context.getLangOpts().IncrementalExtensions &&
524 GlobalTopLevelStmtBlockInFlight.first) {
525 const TopLevelStmtDecl *TLSD = GlobalTopLevelStmtBlockInFlight.second;
526 GlobalTopLevelStmtBlockInFlight.first->FinishFunction(TLSD->getEndLoc());
527 GlobalTopLevelStmtBlockInFlight = {nullptr, nullptr};
528 }
529
530 if (CXX20ModuleInits && Primary && Primary->isInterfaceOrPartition())
531 EmitCXXModuleInitFunc(Primary);
532 else
533 EmitCXXGlobalInitFunc();
534 EmitCXXGlobalCleanUpFunc();
535 registerGlobalDtorsWithAtExit();
536 EmitCXXThreadLocalInitFunc();
537 if (ObjCRuntime)
538 if (llvm::Function *ObjCInitFunction = ObjCRuntime->ModuleInitFunction())
539 AddGlobalCtor(ObjCInitFunction);
540 if (Context.getLangOpts().CUDA && CUDARuntime) {
541 if (llvm::Function *CudaCtorFunction = CUDARuntime->finalizeModule())
542 AddGlobalCtor(CudaCtorFunction);
543 }
544 if (OpenMPRuntime) {
545 if (llvm::Function *OpenMPRequiresDirectiveRegFun =
546 OpenMPRuntime->emitRequiresDirectiveRegFun()) {
547 AddGlobalCtor(OpenMPRequiresDirectiveRegFun, 0);
548 }
549 OpenMPRuntime->createOffloadEntriesAndInfoMetadata();
550 OpenMPRuntime->clear();
551 }
552 if (PGOReader) {
553 getModule().setProfileSummary(
554 PGOReader->getSummary(/* UseCS */ false).getMD(VMContext),
555 llvm::ProfileSummary::PSK_Instr);
556 if (PGOStats.hasDiagnostics())
557 PGOStats.reportDiagnostics(getDiags(), getCodeGenOpts().MainFileName);
558 }
559 llvm::stable_sort(GlobalCtors, [](const Structor &L, const Structor &R) {
560 return L.LexOrder < R.LexOrder;
561 });
562 EmitCtorList(GlobalCtors, "llvm.global_ctors");
563 EmitCtorList(GlobalDtors, "llvm.global_dtors");
564 EmitGlobalAnnotations();
565 EmitStaticExternCAliases();
566 checkAliases();
567 EmitDeferredUnusedCoverageMappings();
568 CodeGenPGO(*this).setValueProfilingFlag(getModule());
569 if (CoverageMapping)
570 CoverageMapping->emit();
571 if (CodeGenOpts.SanitizeCfiCrossDso) {
572 CodeGenFunction(*this).EmitCfiCheckFail();
573 CodeGenFunction(*this).EmitCfiCheckStub();
574 }
575 if (LangOpts.Sanitize.has(SanitizerKind::KCFI))
576 finalizeKCFITypes();
577 emitAtAvailableLinkGuard();
578 if (Context.getTargetInfo().getTriple().isWasm())
579 EmitMainVoidAlias();
580
581 if (getTriple().isAMDGPU()) {
582 // Emit reference of __amdgpu_device_library_preserve_asan_functions to
583 // preserve ASAN functions in bitcode libraries.
584 if (LangOpts.Sanitize.has(SanitizerKind::Address)) {
585 auto *FT = llvm::FunctionType::get(VoidTy, {});
586 auto *F = llvm::Function::Create(
587 FT, llvm::GlobalValue::ExternalLinkage,
588 "__amdgpu_device_library_preserve_asan_functions", &getModule());
589 auto *Var = new llvm::GlobalVariable(
590 getModule(), FT->getPointerTo(),
591 /*isConstant=*/true, llvm::GlobalValue::WeakAnyLinkage, F,
592 "__amdgpu_device_library_preserve_asan_functions_ptr", nullptr,
593 llvm::GlobalVariable::NotThreadLocal);
594 addCompilerUsedGlobal(Var);
595 }
596 // Emit amdgpu_code_object_version module flag, which is code object version
597 // times 100.
598 if (getTarget().getTargetOpts().CodeObjectVersion !=
599 TargetOptions::COV_None) {
600 getModule().addModuleFlag(llvm::Module::Error,
601 "amdgpu_code_object_version",
602 getTarget().getTargetOpts().CodeObjectVersion);
603 }
604 }
605
606 // Emit a global array containing all external kernels or device variables
607 // used by host functions and mark it as used for CUDA/HIP. This is necessary
608 // to get kernels or device variables in archives linked in even if these
609 // kernels or device variables are only used in host functions.
610 if (!Context.CUDAExternalDeviceDeclODRUsedByHost.empty()) {
611 SmallVector<llvm::Constant *, 8> UsedArray;
612 for (auto D : Context.CUDAExternalDeviceDeclODRUsedByHost) {
613 GlobalDecl GD;
614 if (auto *FD = dyn_cast<FunctionDecl>(D))
615 GD = GlobalDecl(FD, KernelReferenceKind::Kernel);
616 else
617 GD = GlobalDecl(D);
618 UsedArray.push_back(llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(
619 GetAddrOfGlobal(GD), Int8PtrTy));
620 }
621
622 llvm::ArrayType *ATy = llvm::ArrayType::get(Int8PtrTy, UsedArray.size());
623
624 auto *GV = new llvm::GlobalVariable(
625 getModule(), ATy, false, llvm::GlobalValue::InternalLinkage,
626 llvm::ConstantArray::get(ATy, UsedArray), "__clang_gpu_used_external");
627 addCompilerUsedGlobal(GV);
628 }
629
630 emitLLVMUsed();
631 if (SanStats)
632 SanStats->finish();
633
634 if (CodeGenOpts.Autolink &&
635 (Context.getLangOpts().Modules || !LinkerOptionsMetadata.empty())) {
636 EmitModuleLinkOptions();
637 }
638
639 // On ELF we pass the dependent library specifiers directly to the linker
640 // without manipulating them. This is in contrast to other platforms where
641 // they are mapped to a specific linker option by the compiler. This
642 // difference is a result of the greater variety of ELF linkers and the fact
643 // that ELF linkers tend to handle libraries in a more complicated fashion
644 // than on other platforms. This forces us to defer handling the dependent
645 // libs to the linker.
646 //
647 // CUDA/HIP device and host libraries are different. Currently there is no
648 // way to differentiate dependent libraries for host or device. Existing
649 // usage of #pragma comment(lib, *) is intended for host libraries on
650 // Windows. Therefore emit llvm.dependent-libraries only for host.
651 if (!ELFDependentLibraries.empty() && !Context.getLangOpts().CUDAIsDevice) {
652 auto *NMD = getModule().getOrInsertNamedMetadata("llvm.dependent-libraries");
653 for (auto *MD : ELFDependentLibraries)
654 NMD->addOperand(MD);
655 }
656
657 // Record mregparm value now so it is visible through rest of codegen.
658 if (Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86)
659 getModule().addModuleFlag(llvm::Module::Error, "NumRegisterParameters",
660 CodeGenOpts.NumRegisterParameters);
661
662 if (CodeGenOpts.DwarfVersion) {
663 getModule().addModuleFlag(llvm::Module::Max, "Dwarf Version",
664 CodeGenOpts.DwarfVersion);
665 }
666
667 if (CodeGenOpts.Dwarf64)
668 getModule().addModuleFlag(llvm::Module::Max, "DWARF64", 1);
669
670 if (Context.getLangOpts().SemanticInterposition)
671 // Require various optimization to respect semantic interposition.
672 getModule().setSemanticInterposition(true);
673
674 if (CodeGenOpts.EmitCodeView) {
675 // Indicate that we want CodeView in the metadata.
676 getModule().addModuleFlag(llvm::Module::Warning, "CodeView", 1);
677 }
678 if (CodeGenOpts.CodeViewGHash) {
679 getModule().addModuleFlag(llvm::Module::Warning, "CodeViewGHash", 1);
680 }
681 if (CodeGenOpts.ControlFlowGuard) {
682 // Function ID tables and checks for Control Flow Guard (cfguard=2).
683 getModule().addModuleFlag(llvm::Module::Warning, "cfguard", 2);
684 } else if (CodeGenOpts.ControlFlowGuardNoChecks) {
685 // Function ID tables for Control Flow Guard (cfguard=1).
686 getModule().addModuleFlag(llvm::Module::Warning, "cfguard", 1);
687 }
688 if (CodeGenOpts.EHContGuard) {
689 // Function ID tables for EH Continuation Guard.
690 getModule().addModuleFlag(llvm::Module::Warning, "ehcontguard", 1);
691 }
692 if (Context.getLangOpts().Kernel) {
693 // Note if we are compiling with /kernel.
694 getModule().addModuleFlag(llvm::Module::Warning, "ms-kernel", 1);
695 }
696 if (CodeGenOpts.OptimizationLevel > 0 && CodeGenOpts.StrictVTablePointers) {
697 // We don't support LTO with 2 with different StrictVTablePointers
698 // FIXME: we could support it by stripping all the information introduced
699 // by StrictVTablePointers.
700
701 getModule().addModuleFlag(llvm::Module::Error, "StrictVTablePointers",1);
702
703 llvm::Metadata *Ops[2] = {
704 llvm::MDString::get(VMContext, "StrictVTablePointers"),
705 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
706 llvm::Type::getInt32Ty(VMContext), 1))};
707
708 getModule().addModuleFlag(llvm::Module::Require,
709 "StrictVTablePointersRequirement",
710 llvm::MDNode::get(VMContext, Ops));
711 }
712 if (getModuleDebugInfo())
713 // We support a single version in the linked module. The LLVM
714 // parser will drop debug info with a different version number
715 // (and warn about it, too).
716 getModule().addModuleFlag(llvm::Module::Warning, "Debug Info Version",
717 llvm::DEBUG_METADATA_VERSION);
718
719 // We need to record the widths of enums and wchar_t, so that we can generate
720 // the correct build attributes in the ARM backend. wchar_size is also used by
721 // TargetLibraryInfo.
722 uint64_t WCharWidth =
723 Context.getTypeSizeInChars(Context.getWideCharType()).getQuantity();
724 getModule().addModuleFlag(llvm::Module::Error, "wchar_size", WCharWidth);
725
726 llvm::Triple::ArchType Arch = Context.getTargetInfo().getTriple().getArch();
727 if ( Arch == llvm::Triple::arm
728 || Arch == llvm::Triple::armeb
729 || Arch == llvm::Triple::thumb
730 || Arch == llvm::Triple::thumbeb) {
731 // The minimum width of an enum in bytes
732 uint64_t EnumWidth = Context.getLangOpts().ShortEnums ? 1 : 4;
733 getModule().addModuleFlag(llvm::Module::Error, "min_enum_size", EnumWidth);
734 }
735
736 if (Arch == llvm::Triple::riscv32 || Arch == llvm::Triple::riscv64) {
737 StringRef ABIStr = Target.getABI();
738 llvm::LLVMContext &Ctx = TheModule.getContext();
739 getModule().addModuleFlag(llvm::Module::Error, "target-abi",
740 llvm::MDString::get(Ctx, ABIStr));
741 }
742
743 if (CodeGenOpts.SanitizeCfiCrossDso) {
744 // Indicate that we want cross-DSO control flow integrity checks.
745 getModule().addModuleFlag(llvm::Module::Override, "Cross-DSO CFI", 1);
746 }
747
748 if (CodeGenOpts.WholeProgramVTables) {
749 // Indicate whether VFE was enabled for this module, so that the
750 // vcall_visibility metadata added under whole program vtables is handled
751 // appropriately in the optimizer.
752 getModule().addModuleFlag(llvm::Module::Error, "Virtual Function Elim",
753 CodeGenOpts.VirtualFunctionElimination);
754 }
755
756 if (LangOpts.Sanitize.has(SanitizerKind::CFIICall)) {
757 getModule().addModuleFlag(llvm::Module::Override,
758 "CFI Canonical Jump Tables",
759 CodeGenOpts.SanitizeCfiCanonicalJumpTables);
760 }
761
762 if (LangOpts.Sanitize.has(SanitizerKind::KCFI)) {
763 getModule().addModuleFlag(llvm::Module::Override, "kcfi", 1);
764 // KCFI assumes patchable-function-prefix is the same for all indirectly
765 // called functions. Store the expected offset for code generation.
766 if (CodeGenOpts.PatchableFunctionEntryOffset)
767 getModule().addModuleFlag(llvm::Module::Override, "kcfi-offset",
768 CodeGenOpts.PatchableFunctionEntryOffset);
769 }
770
771 if (CodeGenOpts.CFProtectionReturn &&
772 Target.checkCFProtectionReturnSupported(getDiags())) {
773 // Indicate that we want to instrument return control flow protection.
774 getModule().addModuleFlag(llvm::Module::Min, "cf-protection-return",
775 1);
776 }
777
778 if (CodeGenOpts.CFProtectionBranch &&
779 Target.checkCFProtectionBranchSupported(getDiags())) {
780 // Indicate that we want to instrument branch control flow protection.
781 getModule().addModuleFlag(llvm::Module::Min, "cf-protection-branch",
782 1);
783 }
784
785 if (CodeGenOpts.FunctionReturnThunks)
786 getModule().addModuleFlag(llvm::Module::Override, "function_return_thunk_extern", 1);
787
788 if (CodeGenOpts.IndirectBranchCSPrefix)
789 getModule().addModuleFlag(llvm::Module::Override, "indirect_branch_cs_prefix", 1);
790
791 // Add module metadata for return address signing (ignoring
792 // non-leaf/all) and stack tagging. These are actually turned on by function
793 // attributes, but we use module metadata to emit build attributes. This is
794 // needed for LTO, where the function attributes are inside bitcode
795 // serialised into a global variable by the time build attributes are
796 // emitted, so we can't access them. LTO objects could be compiled with
797 // different flags therefore module flags are set to "Min" behavior to achieve
798 // the same end result of the normal build where e.g BTI is off if any object
799 // doesn't support it.
800 if (Context.getTargetInfo().hasFeature("ptrauth") &&
801 LangOpts.getSignReturnAddressScope() !=
802 LangOptions::SignReturnAddressScopeKind::None)
803 getModule().addModuleFlag(llvm::Module::Override,
804 "sign-return-address-buildattr", 1);
805 if (LangOpts.Sanitize.has(SanitizerKind::MemtagStack))
806 getModule().addModuleFlag(llvm::Module::Override,
807 "tag-stack-memory-buildattr", 1);
808
809 if (Arch == llvm::Triple::thumb || Arch == llvm::Triple::thumbeb ||
810 Arch == llvm::Triple::arm || Arch == llvm::Triple::armeb ||
811 Arch == llvm::Triple::aarch64 || Arch == llvm::Triple::aarch64_32 ||
812 Arch == llvm::Triple::aarch64_be) {
813 if (LangOpts.BranchTargetEnforcement)
814 getModule().addModuleFlag(llvm::Module::Min, "branch-target-enforcement",
815 1);
816 if (LangOpts.hasSignReturnAddress())
817 getModule().addModuleFlag(llvm::Module::Min, "sign-return-address", 1);
818 if (LangOpts.isSignReturnAddressScopeAll())
819 getModule().addModuleFlag(llvm::Module::Min, "sign-return-address-all",
820 1);
821 if (!LangOpts.isSignReturnAddressWithAKey())
822 getModule().addModuleFlag(llvm::Module::Min,
823 "sign-return-address-with-bkey", 1);
824 }
825
826 if (!CodeGenOpts.MemoryProfileOutput.empty()) {
827 llvm::LLVMContext &Ctx = TheModule.getContext();
828 getModule().addModuleFlag(
829 llvm::Module::Error, "MemProfProfileFilename",
830 llvm::MDString::get(Ctx, CodeGenOpts.MemoryProfileOutput));
831 }
832
833 if (LangOpts.CUDAIsDevice && getTriple().isNVPTX()) {
834 // Indicate whether __nvvm_reflect should be configured to flush denormal
835 // floating point values to 0. (This corresponds to its "__CUDA_FTZ"
836 // property.)
837 getModule().addModuleFlag(llvm::Module::Override, "nvvm-reflect-ftz",
838 CodeGenOpts.FP32DenormalMode.Output !=
839 llvm::DenormalMode::IEEE);
840 }
841
842 if (LangOpts.EHAsynch)
843 getModule().addModuleFlag(llvm::Module::Warning, "eh-asynch", 1);
844
845 // Indicate whether this Module was compiled with -fopenmp
846 if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd)
847 getModule().addModuleFlag(llvm::Module::Max, "openmp", LangOpts.OpenMP);
848 if (getLangOpts().OpenMPIsDevice)
849 getModule().addModuleFlag(llvm::Module::Max, "openmp-device",
850 LangOpts.OpenMP);
851
852 // Emit OpenCL specific module metadata: OpenCL/SPIR version.
853 if (LangOpts.OpenCL || (LangOpts.CUDAIsDevice && getTriple().isSPIRV())) {
854 EmitOpenCLMetadata();
855 // Emit SPIR version.
856 if (getTriple().isSPIR()) {
857 // SPIR v2.0 s2.12 - The SPIR version used by the module is stored in the
858 // opencl.spir.version named metadata.
859 // C++ for OpenCL has a distinct mapping for version compatibility with
860 // OpenCL.
861 auto Version = LangOpts.getOpenCLCompatibleVersion();
862 llvm::Metadata *SPIRVerElts[] = {
863 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
864 Int32Ty, Version / 100)),
865 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
866 Int32Ty, (Version / 100 > 1) ? 0 : 2))};
867 llvm::NamedMDNode *SPIRVerMD =
868 TheModule.getOrInsertNamedMetadata("opencl.spir.version");
869 llvm::LLVMContext &Ctx = TheModule.getContext();
870 SPIRVerMD->addOperand(llvm::MDNode::get(Ctx, SPIRVerElts));
871 }
872 }
873
874 // HLSL related end of code gen work items.
875 if (LangOpts.HLSL)
876 getHLSLRuntime().finishCodeGen();
877
878 if (uint32_t PLevel = Context.getLangOpts().PICLevel) {
879 assert(PLevel < 3 && "Invalid PIC Level");
880 getModule().setPICLevel(static_cast<llvm::PICLevel::Level>(PLevel));
881 if (Context.getLangOpts().PIE)
882 getModule().setPIELevel(static_cast<llvm::PIELevel::Level>(PLevel));
883 }
884
885 if (getCodeGenOpts().CodeModel.size() > 0) {
886 unsigned CM = llvm::StringSwitch<unsigned>(getCodeGenOpts().CodeModel)
887 .Case("tiny", llvm::CodeModel::Tiny)
888 .Case("small", llvm::CodeModel::Small)
889 .Case("kernel", llvm::CodeModel::Kernel)
890 .Case("medium", llvm::CodeModel::Medium)
891 .Case("large", llvm::CodeModel::Large)
892 .Default(~0u);
893 if (CM != ~0u) {
894 llvm::CodeModel::Model codeModel = static_cast<llvm::CodeModel::Model>(CM);
895 getModule().setCodeModel(codeModel);
896 }
897 }
898
899 if (CodeGenOpts.NoPLT)
900 getModule().setRtLibUseGOT();
901 if (CodeGenOpts.UnwindTables)
902 getModule().setUwtable(llvm::UWTableKind(CodeGenOpts.UnwindTables));
903
904 switch (CodeGenOpts.getFramePointer()) {
905 case CodeGenOptions::FramePointerKind::None:
906 // 0 ("none") is the default.
907 break;
908 case CodeGenOptions::FramePointerKind::NonLeaf:
909 getModule().setFramePointer(llvm::FramePointerKind::NonLeaf);
910 break;
911 case CodeGenOptions::FramePointerKind::All:
912 getModule().setFramePointer(llvm::FramePointerKind::All);
913 break;
914 }
915
916 SimplifyPersonality();
917
918 if (getCodeGenOpts().EmitDeclMetadata)
919 EmitDeclMetadata();
920
921 if (getCodeGenOpts().EmitGcovArcs || getCodeGenOpts().EmitGcovNotes)
922 EmitCoverageFile();
923
924 if (CGDebugInfo *DI = getModuleDebugInfo())
925 DI->finalize();
926
927 if (getCodeGenOpts().EmitVersionIdentMetadata)
928 EmitVersionIdentMetadata();
929
930 if (!getCodeGenOpts().RecordCommandLine.empty())
931 EmitCommandLineMetadata();
932
933 if (!getCodeGenOpts().StackProtectorGuard.empty())
934 getModule().setStackProtectorGuard(getCodeGenOpts().StackProtectorGuard);
935 if (!getCodeGenOpts().StackProtectorGuardReg.empty())
936 getModule().setStackProtectorGuardReg(
937 getCodeGenOpts().StackProtectorGuardReg);
938 if (!getCodeGenOpts().StackProtectorGuardSymbol.empty())
939 getModule().setStackProtectorGuardSymbol(
940 getCodeGenOpts().StackProtectorGuardSymbol);
941 if (getCodeGenOpts().StackProtectorGuardOffset != INT_MAX)
942 getModule().setStackProtectorGuardOffset(
943 getCodeGenOpts().StackProtectorGuardOffset);
944 if (getCodeGenOpts().StackAlignment)
945 getModule().setOverrideStackAlignment(getCodeGenOpts().StackAlignment);
946 if (getCodeGenOpts().SkipRaxSetup)
947 getModule().addModuleFlag(llvm::Module::Override, "SkipRaxSetup", 1);
948
949 getTargetCodeGenInfo().emitTargetMetadata(*this, MangledDeclNames);
950
951 EmitBackendOptionsMetadata(getCodeGenOpts());
952
953 // If there is device offloading code embed it in the host now.
954 EmbedObject(&getModule(), CodeGenOpts, getDiags());
955
956 // Set visibility from DLL storage class
957 // We do this at the end of LLVM IR generation; after any operation
958 // that might affect the DLL storage class or the visibility, and
959 // before anything that might act on these.
960 setVisibilityFromDLLStorageClass(LangOpts, getModule());
961 }
962
EmitOpenCLMetadata()963 void CodeGenModule::EmitOpenCLMetadata() {
964 // SPIR v2.0 s2.13 - The OpenCL version used by the module is stored in the
965 // opencl.ocl.version named metadata node.
966 // C++ for OpenCL has a distinct mapping for versions compatibile with OpenCL.
967 auto Version = LangOpts.getOpenCLCompatibleVersion();
968 llvm::Metadata *OCLVerElts[] = {
969 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
970 Int32Ty, Version / 100)),
971 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
972 Int32Ty, (Version % 100) / 10))};
973 llvm::NamedMDNode *OCLVerMD =
974 TheModule.getOrInsertNamedMetadata("opencl.ocl.version");
975 llvm::LLVMContext &Ctx = TheModule.getContext();
976 OCLVerMD->addOperand(llvm::MDNode::get(Ctx, OCLVerElts));
977 }
978
EmitBackendOptionsMetadata(const CodeGenOptions CodeGenOpts)979 void CodeGenModule::EmitBackendOptionsMetadata(
980 const CodeGenOptions CodeGenOpts) {
981 if (getTriple().isRISCV()) {
982 getModule().addModuleFlag(llvm::Module::Warning, "SmallDataLimit",
983 CodeGenOpts.SmallDataLimit);
984 }
985 }
986
UpdateCompletedType(const TagDecl * TD)987 void CodeGenModule::UpdateCompletedType(const TagDecl *TD) {
988 // Make sure that this type is translated.
989 Types.UpdateCompletedType(TD);
990 }
991
RefreshTypeCacheForClass(const CXXRecordDecl * RD)992 void CodeGenModule::RefreshTypeCacheForClass(const CXXRecordDecl *RD) {
993 // Make sure that this type is translated.
994 Types.RefreshTypeCacheForClass(RD);
995 }
996
getTBAATypeInfo(QualType QTy)997 llvm::MDNode *CodeGenModule::getTBAATypeInfo(QualType QTy) {
998 if (!TBAA)
999 return nullptr;
1000 return TBAA->getTypeInfo(QTy);
1001 }
1002
getTBAAAccessInfo(QualType AccessType)1003 TBAAAccessInfo CodeGenModule::getTBAAAccessInfo(QualType AccessType) {
1004 if (!TBAA)
1005 return TBAAAccessInfo();
1006 if (getLangOpts().CUDAIsDevice) {
1007 // As CUDA builtin surface/texture types are replaced, skip generating TBAA
1008 // access info.
1009 if (AccessType->isCUDADeviceBuiltinSurfaceType()) {
1010 if (getTargetCodeGenInfo().getCUDADeviceBuiltinSurfaceDeviceType() !=
1011 nullptr)
1012 return TBAAAccessInfo();
1013 } else if (AccessType->isCUDADeviceBuiltinTextureType()) {
1014 if (getTargetCodeGenInfo().getCUDADeviceBuiltinTextureDeviceType() !=
1015 nullptr)
1016 return TBAAAccessInfo();
1017 }
1018 }
1019 return TBAA->getAccessInfo(AccessType);
1020 }
1021
1022 TBAAAccessInfo
getTBAAVTablePtrAccessInfo(llvm::Type * VTablePtrType)1023 CodeGenModule::getTBAAVTablePtrAccessInfo(llvm::Type *VTablePtrType) {
1024 if (!TBAA)
1025 return TBAAAccessInfo();
1026 return TBAA->getVTablePtrAccessInfo(VTablePtrType);
1027 }
1028
getTBAAStructInfo(QualType QTy)1029 llvm::MDNode *CodeGenModule::getTBAAStructInfo(QualType QTy) {
1030 if (!TBAA)
1031 return nullptr;
1032 return TBAA->getTBAAStructInfo(QTy);
1033 }
1034
getTBAABaseTypeInfo(QualType QTy)1035 llvm::MDNode *CodeGenModule::getTBAABaseTypeInfo(QualType QTy) {
1036 if (!TBAA)
1037 return nullptr;
1038 return TBAA->getBaseTypeInfo(QTy);
1039 }
1040
getTBAAAccessTagInfo(TBAAAccessInfo Info)1041 llvm::MDNode *CodeGenModule::getTBAAAccessTagInfo(TBAAAccessInfo Info) {
1042 if (!TBAA)
1043 return nullptr;
1044 return TBAA->getAccessTagInfo(Info);
1045 }
1046
mergeTBAAInfoForCast(TBAAAccessInfo SourceInfo,TBAAAccessInfo TargetInfo)1047 TBAAAccessInfo CodeGenModule::mergeTBAAInfoForCast(TBAAAccessInfo SourceInfo,
1048 TBAAAccessInfo TargetInfo) {
1049 if (!TBAA)
1050 return TBAAAccessInfo();
1051 return TBAA->mergeTBAAInfoForCast(SourceInfo, TargetInfo);
1052 }
1053
1054 TBAAAccessInfo
mergeTBAAInfoForConditionalOperator(TBAAAccessInfo InfoA,TBAAAccessInfo InfoB)1055 CodeGenModule::mergeTBAAInfoForConditionalOperator(TBAAAccessInfo InfoA,
1056 TBAAAccessInfo InfoB) {
1057 if (!TBAA)
1058 return TBAAAccessInfo();
1059 return TBAA->mergeTBAAInfoForConditionalOperator(InfoA, InfoB);
1060 }
1061
1062 TBAAAccessInfo
mergeTBAAInfoForMemoryTransfer(TBAAAccessInfo DestInfo,TBAAAccessInfo SrcInfo)1063 CodeGenModule::mergeTBAAInfoForMemoryTransfer(TBAAAccessInfo DestInfo,
1064 TBAAAccessInfo SrcInfo) {
1065 if (!TBAA)
1066 return TBAAAccessInfo();
1067 return TBAA->mergeTBAAInfoForConditionalOperator(DestInfo, SrcInfo);
1068 }
1069
DecorateInstructionWithTBAA(llvm::Instruction * Inst,TBAAAccessInfo TBAAInfo)1070 void CodeGenModule::DecorateInstructionWithTBAA(llvm::Instruction *Inst,
1071 TBAAAccessInfo TBAAInfo) {
1072 if (llvm::MDNode *Tag = getTBAAAccessTagInfo(TBAAInfo))
1073 Inst->setMetadata(llvm::LLVMContext::MD_tbaa, Tag);
1074 }
1075
DecorateInstructionWithInvariantGroup(llvm::Instruction * I,const CXXRecordDecl * RD)1076 void CodeGenModule::DecorateInstructionWithInvariantGroup(
1077 llvm::Instruction *I, const CXXRecordDecl *RD) {
1078 I->setMetadata(llvm::LLVMContext::MD_invariant_group,
1079 llvm::MDNode::get(getLLVMContext(), {}));
1080 }
1081
Error(SourceLocation loc,StringRef message)1082 void CodeGenModule::Error(SourceLocation loc, StringRef message) {
1083 unsigned diagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error, "%0");
1084 getDiags().Report(Context.getFullLoc(loc), diagID) << message;
1085 }
1086
1087 /// ErrorUnsupported - Print out an error that codegen doesn't support the
1088 /// specified stmt yet.
ErrorUnsupported(const Stmt * S,const char * Type)1089 void CodeGenModule::ErrorUnsupported(const Stmt *S, const char *Type) {
1090 unsigned DiagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error,
1091 "cannot compile this %0 yet");
1092 std::string Msg = Type;
1093 getDiags().Report(Context.getFullLoc(S->getBeginLoc()), DiagID)
1094 << Msg << S->getSourceRange();
1095 }
1096
1097 /// ErrorUnsupported - Print out an error that codegen doesn't support the
1098 /// specified decl yet.
ErrorUnsupported(const Decl * D,const char * Type)1099 void CodeGenModule::ErrorUnsupported(const Decl *D, const char *Type) {
1100 unsigned DiagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error,
1101 "cannot compile this %0 yet");
1102 std::string Msg = Type;
1103 getDiags().Report(Context.getFullLoc(D->getLocation()), DiagID) << Msg;
1104 }
1105
getSize(CharUnits size)1106 llvm::ConstantInt *CodeGenModule::getSize(CharUnits size) {
1107 return llvm::ConstantInt::get(SizeTy, size.getQuantity());
1108 }
1109
setGlobalVisibility(llvm::GlobalValue * GV,const NamedDecl * D) const1110 void CodeGenModule::setGlobalVisibility(llvm::GlobalValue *GV,
1111 const NamedDecl *D) const {
1112 // Internal definitions always have default visibility.
1113 if (GV->hasLocalLinkage()) {
1114 GV->setVisibility(llvm::GlobalValue::DefaultVisibility);
1115 return;
1116 }
1117 if (!D)
1118 return;
1119 // Set visibility for definitions, and for declarations if requested globally
1120 // or set explicitly.
1121 LinkageInfo LV = D->getLinkageAndVisibility();
1122 if (GV->hasDLLExportStorageClass() || GV->hasDLLImportStorageClass()) {
1123 // Reject incompatible dlllstorage and visibility annotations.
1124 if (!LV.isVisibilityExplicit())
1125 return;
1126 if (GV->hasDLLExportStorageClass()) {
1127 if (LV.getVisibility() == HiddenVisibility)
1128 getDiags().Report(D->getLocation(),
1129 diag::err_hidden_visibility_dllexport);
1130 } else if (LV.getVisibility() != DefaultVisibility) {
1131 getDiags().Report(D->getLocation(),
1132 diag::err_non_default_visibility_dllimport);
1133 }
1134 return;
1135 }
1136
1137 if (LV.isVisibilityExplicit() || getLangOpts().SetVisibilityForExternDecls ||
1138 !GV->isDeclarationForLinker())
1139 GV->setVisibility(GetLLVMVisibility(LV.getVisibility()));
1140 }
1141
shouldAssumeDSOLocal(const CodeGenModule & CGM,llvm::GlobalValue * GV)1142 static bool shouldAssumeDSOLocal(const CodeGenModule &CGM,
1143 llvm::GlobalValue *GV) {
1144 if (GV->hasLocalLinkage())
1145 return true;
1146
1147 if (!GV->hasDefaultVisibility() && !GV->hasExternalWeakLinkage())
1148 return true;
1149
1150 // DLLImport explicitly marks the GV as external.
1151 if (GV->hasDLLImportStorageClass())
1152 return false;
1153
1154 const llvm::Triple &TT = CGM.getTriple();
1155 if (TT.isWindowsGNUEnvironment()) {
1156 // In MinGW, variables without DLLImport can still be automatically
1157 // imported from a DLL by the linker; don't mark variables that
1158 // potentially could come from another DLL as DSO local.
1159
1160 // With EmulatedTLS, TLS variables can be autoimported from other DLLs
1161 // (and this actually happens in the public interface of libstdc++), so
1162 // such variables can't be marked as DSO local. (Native TLS variables
1163 // can't be dllimported at all, though.)
1164 if (GV->isDeclarationForLinker() && isa<llvm::GlobalVariable>(GV) &&
1165 (!GV->isThreadLocal() || CGM.getCodeGenOpts().EmulatedTLS))
1166 return false;
1167 }
1168
1169 // On COFF, don't mark 'extern_weak' symbols as DSO local. If these symbols
1170 // remain unresolved in the link, they can be resolved to zero, which is
1171 // outside the current DSO.
1172 if (TT.isOSBinFormatCOFF() && GV->hasExternalWeakLinkage())
1173 return false;
1174
1175 // Every other GV is local on COFF.
1176 // Make an exception for windows OS in the triple: Some firmware builds use
1177 // *-win32-macho triples. This (accidentally?) produced windows relocations
1178 // without GOT tables in older clang versions; Keep this behaviour.
1179 // FIXME: even thread local variables?
1180 if (TT.isOSBinFormatCOFF() || (TT.isOSWindows() && TT.isOSBinFormatMachO()))
1181 return true;
1182
1183 // Only handle COFF and ELF for now.
1184 if (!TT.isOSBinFormatELF())
1185 return false;
1186
1187 // If this is not an executable, don't assume anything is local.
1188 const auto &CGOpts = CGM.getCodeGenOpts();
1189 llvm::Reloc::Model RM = CGOpts.RelocationModel;
1190 const auto &LOpts = CGM.getLangOpts();
1191 if (RM != llvm::Reloc::Static && !LOpts.PIE) {
1192 // On ELF, if -fno-semantic-interposition is specified and the target
1193 // supports local aliases, there will be neither CC1
1194 // -fsemantic-interposition nor -fhalf-no-semantic-interposition. Set
1195 // dso_local on the function if using a local alias is preferable (can avoid
1196 // PLT indirection).
1197 if (!(isa<llvm::Function>(GV) && GV->canBenefitFromLocalAlias()))
1198 return false;
1199 return !(CGM.getLangOpts().SemanticInterposition ||
1200 CGM.getLangOpts().HalfNoSemanticInterposition);
1201 }
1202
1203 // A definition cannot be preempted from an executable.
1204 if (!GV->isDeclarationForLinker())
1205 return true;
1206
1207 // Most PIC code sequences that assume that a symbol is local cannot produce a
1208 // 0 if it turns out the symbol is undefined. While this is ABI and relocation
1209 // depended, it seems worth it to handle it here.
1210 if (RM == llvm::Reloc::PIC_ && GV->hasExternalWeakLinkage())
1211 return false;
1212
1213 // PowerPC64 prefers TOC indirection to avoid copy relocations.
1214 if (TT.isPPC64())
1215 return false;
1216
1217 if (CGOpts.DirectAccessExternalData) {
1218 // If -fdirect-access-external-data (default for -fno-pic), set dso_local
1219 // for non-thread-local variables. If the symbol is not defined in the
1220 // executable, a copy relocation will be needed at link time. dso_local is
1221 // excluded for thread-local variables because they generally don't support
1222 // copy relocations.
1223 if (auto *Var = dyn_cast<llvm::GlobalVariable>(GV))
1224 if (!Var->isThreadLocal())
1225 return true;
1226
1227 // -fno-pic sets dso_local on a function declaration to allow direct
1228 // accesses when taking its address (similar to a data symbol). If the
1229 // function is not defined in the executable, a canonical PLT entry will be
1230 // needed at link time. -fno-direct-access-external-data can avoid the
1231 // canonical PLT entry. We don't generalize this condition to -fpie/-fpic as
1232 // it could just cause trouble without providing perceptible benefits.
1233 if (isa<llvm::Function>(GV) && !CGOpts.NoPLT && RM == llvm::Reloc::Static)
1234 return true;
1235 }
1236
1237 // If we can use copy relocations we can assume it is local.
1238
1239 // Otherwise don't assume it is local.
1240 return false;
1241 }
1242
setDSOLocal(llvm::GlobalValue * GV) const1243 void CodeGenModule::setDSOLocal(llvm::GlobalValue *GV) const {
1244 GV->setDSOLocal(shouldAssumeDSOLocal(*this, GV));
1245 }
1246
setDLLImportDLLExport(llvm::GlobalValue * GV,GlobalDecl GD) const1247 void CodeGenModule::setDLLImportDLLExport(llvm::GlobalValue *GV,
1248 GlobalDecl GD) const {
1249 const auto *D = dyn_cast<NamedDecl>(GD.getDecl());
1250 // C++ destructors have a few C++ ABI specific special cases.
1251 if (const auto *Dtor = dyn_cast_or_null<CXXDestructorDecl>(D)) {
1252 getCXXABI().setCXXDestructorDLLStorage(GV, Dtor, GD.getDtorType());
1253 return;
1254 }
1255 setDLLImportDLLExport(GV, D);
1256 }
1257
setDLLImportDLLExport(llvm::GlobalValue * GV,const NamedDecl * D) const1258 void CodeGenModule::setDLLImportDLLExport(llvm::GlobalValue *GV,
1259 const NamedDecl *D) const {
1260 if (D && D->isExternallyVisible()) {
1261 if (D->hasAttr<DLLImportAttr>())
1262 GV->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass);
1263 else if ((D->hasAttr<DLLExportAttr>() ||
1264 shouldMapVisibilityToDLLExport(D)) &&
1265 !GV->isDeclarationForLinker())
1266 GV->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass);
1267 }
1268 }
1269
setGVProperties(llvm::GlobalValue * GV,GlobalDecl GD) const1270 void CodeGenModule::setGVProperties(llvm::GlobalValue *GV,
1271 GlobalDecl GD) const {
1272 setDLLImportDLLExport(GV, GD);
1273 setGVPropertiesAux(GV, dyn_cast<NamedDecl>(GD.getDecl()));
1274 }
1275
setGVProperties(llvm::GlobalValue * GV,const NamedDecl * D) const1276 void CodeGenModule::setGVProperties(llvm::GlobalValue *GV,
1277 const NamedDecl *D) const {
1278 setDLLImportDLLExport(GV, D);
1279 setGVPropertiesAux(GV, D);
1280 }
1281
setGVPropertiesAux(llvm::GlobalValue * GV,const NamedDecl * D) const1282 void CodeGenModule::setGVPropertiesAux(llvm::GlobalValue *GV,
1283 const NamedDecl *D) const {
1284 setGlobalVisibility(GV, D);
1285 setDSOLocal(GV);
1286 GV->setPartition(CodeGenOpts.SymbolPartition);
1287 }
1288
GetLLVMTLSModel(StringRef S)1289 static llvm::GlobalVariable::ThreadLocalMode GetLLVMTLSModel(StringRef S) {
1290 return llvm::StringSwitch<llvm::GlobalVariable::ThreadLocalMode>(S)
1291 .Case("global-dynamic", llvm::GlobalVariable::GeneralDynamicTLSModel)
1292 .Case("local-dynamic", llvm::GlobalVariable::LocalDynamicTLSModel)
1293 .Case("initial-exec", llvm::GlobalVariable::InitialExecTLSModel)
1294 .Case("local-exec", llvm::GlobalVariable::LocalExecTLSModel);
1295 }
1296
1297 llvm::GlobalVariable::ThreadLocalMode
GetDefaultLLVMTLSModel() const1298 CodeGenModule::GetDefaultLLVMTLSModel() const {
1299 switch (CodeGenOpts.getDefaultTLSModel()) {
1300 case CodeGenOptions::GeneralDynamicTLSModel:
1301 return llvm::GlobalVariable::GeneralDynamicTLSModel;
1302 case CodeGenOptions::LocalDynamicTLSModel:
1303 return llvm::GlobalVariable::LocalDynamicTLSModel;
1304 case CodeGenOptions::InitialExecTLSModel:
1305 return llvm::GlobalVariable::InitialExecTLSModel;
1306 case CodeGenOptions::LocalExecTLSModel:
1307 return llvm::GlobalVariable::LocalExecTLSModel;
1308 }
1309 llvm_unreachable("Invalid TLS model!");
1310 }
1311
setTLSMode(llvm::GlobalValue * GV,const VarDecl & D) const1312 void CodeGenModule::setTLSMode(llvm::GlobalValue *GV, const VarDecl &D) const {
1313 assert(D.getTLSKind() && "setting TLS mode on non-TLS var!");
1314
1315 llvm::GlobalValue::ThreadLocalMode TLM;
1316 TLM = GetDefaultLLVMTLSModel();
1317
1318 // Override the TLS model if it is explicitly specified.
1319 if (const TLSModelAttr *Attr = D.getAttr<TLSModelAttr>()) {
1320 TLM = GetLLVMTLSModel(Attr->getModel());
1321 }
1322
1323 GV->setThreadLocalMode(TLM);
1324 }
1325
getCPUSpecificMangling(const CodeGenModule & CGM,StringRef Name)1326 static std::string getCPUSpecificMangling(const CodeGenModule &CGM,
1327 StringRef Name) {
1328 const TargetInfo &Target = CGM.getTarget();
1329 return (Twine('.') + Twine(Target.CPUSpecificManglingCharacter(Name))).str();
1330 }
1331
AppendCPUSpecificCPUDispatchMangling(const CodeGenModule & CGM,const CPUSpecificAttr * Attr,unsigned CPUIndex,raw_ostream & Out)1332 static void AppendCPUSpecificCPUDispatchMangling(const CodeGenModule &CGM,
1333 const CPUSpecificAttr *Attr,
1334 unsigned CPUIndex,
1335 raw_ostream &Out) {
1336 // cpu_specific gets the current name, dispatch gets the resolver if IFunc is
1337 // supported.
1338 if (Attr)
1339 Out << getCPUSpecificMangling(CGM, Attr->getCPUName(CPUIndex)->getName());
1340 else if (CGM.getTarget().supportsIFunc())
1341 Out << ".resolver";
1342 }
1343
AppendTargetVersionMangling(const CodeGenModule & CGM,const TargetVersionAttr * Attr,raw_ostream & Out)1344 static void AppendTargetVersionMangling(const CodeGenModule &CGM,
1345 const TargetVersionAttr *Attr,
1346 raw_ostream &Out) {
1347 if (Attr->isDefaultVersion())
1348 return;
1349 Out << "._";
1350 llvm::SmallVector<StringRef, 8> Feats;
1351 Attr->getFeatures(Feats);
1352 for (const auto &Feat : Feats) {
1353 Out << 'M';
1354 Out << Feat;
1355 }
1356 }
1357
AppendTargetMangling(const CodeGenModule & CGM,const TargetAttr * Attr,raw_ostream & Out)1358 static void AppendTargetMangling(const CodeGenModule &CGM,
1359 const TargetAttr *Attr, raw_ostream &Out) {
1360 if (Attr->isDefaultVersion())
1361 return;
1362
1363 Out << '.';
1364 const TargetInfo &Target = CGM.getTarget();
1365 ParsedTargetAttr Info = Target.parseTargetAttr(Attr->getFeaturesStr());
1366 llvm::sort(Info.Features, [&Target](StringRef LHS, StringRef RHS) {
1367 // Multiversioning doesn't allow "no-${feature}", so we can
1368 // only have "+" prefixes here.
1369 assert(LHS.startswith("+") && RHS.startswith("+") &&
1370 "Features should always have a prefix.");
1371 return Target.multiVersionSortPriority(LHS.substr(1)) >
1372 Target.multiVersionSortPriority(RHS.substr(1));
1373 });
1374
1375 bool IsFirst = true;
1376
1377 if (!Info.CPU.empty()) {
1378 IsFirst = false;
1379 Out << "arch_" << Info.CPU;
1380 }
1381
1382 for (StringRef Feat : Info.Features) {
1383 if (!IsFirst)
1384 Out << '_';
1385 IsFirst = false;
1386 Out << Feat.substr(1);
1387 }
1388 }
1389
1390 // Returns true if GD is a function decl with internal linkage and
1391 // needs a unique suffix after the mangled name.
isUniqueInternalLinkageDecl(GlobalDecl GD,CodeGenModule & CGM)1392 static bool isUniqueInternalLinkageDecl(GlobalDecl GD,
1393 CodeGenModule &CGM) {
1394 const Decl *D = GD.getDecl();
1395 return !CGM.getModuleNameHash().empty() && isa<FunctionDecl>(D) &&
1396 (CGM.getFunctionLinkage(GD) == llvm::GlobalValue::InternalLinkage);
1397 }
1398
AppendTargetClonesMangling(const CodeGenModule & CGM,const TargetClonesAttr * Attr,unsigned VersionIndex,raw_ostream & Out)1399 static void AppendTargetClonesMangling(const CodeGenModule &CGM,
1400 const TargetClonesAttr *Attr,
1401 unsigned VersionIndex,
1402 raw_ostream &Out) {
1403 if (CGM.getTarget().getTriple().isAArch64()) {
1404 StringRef FeatureStr = Attr->getFeatureStr(VersionIndex);
1405 if (FeatureStr == "default")
1406 return;
1407 Out << "._";
1408 SmallVector<StringRef, 8> Features;
1409 FeatureStr.split(Features, "+");
1410 for (auto &Feat : Features) {
1411 Out << 'M';
1412 Out << Feat;
1413 }
1414 } else {
1415 Out << '.';
1416 StringRef FeatureStr = Attr->getFeatureStr(VersionIndex);
1417 if (FeatureStr.startswith("arch="))
1418 Out << "arch_" << FeatureStr.substr(sizeof("arch=") - 1);
1419 else
1420 Out << FeatureStr;
1421
1422 Out << '.' << Attr->getMangledIndex(VersionIndex);
1423 }
1424 }
1425
getMangledNameImpl(CodeGenModule & CGM,GlobalDecl GD,const NamedDecl * ND,bool OmitMultiVersionMangling=false)1426 static std::string getMangledNameImpl(CodeGenModule &CGM, GlobalDecl GD,
1427 const NamedDecl *ND,
1428 bool OmitMultiVersionMangling = false) {
1429 SmallString<256> Buffer;
1430 llvm::raw_svector_ostream Out(Buffer);
1431 MangleContext &MC = CGM.getCXXABI().getMangleContext();
1432 if (!CGM.getModuleNameHash().empty())
1433 MC.needsUniqueInternalLinkageNames();
1434 bool ShouldMangle = MC.shouldMangleDeclName(ND);
1435 if (ShouldMangle)
1436 MC.mangleName(GD.getWithDecl(ND), Out);
1437 else {
1438 IdentifierInfo *II = ND->getIdentifier();
1439 assert(II && "Attempt to mangle unnamed decl.");
1440 const auto *FD = dyn_cast<FunctionDecl>(ND);
1441
1442 if (FD &&
1443 FD->getType()->castAs<FunctionType>()->getCallConv() == CC_X86RegCall) {
1444 Out << "__regcall3__" << II->getName();
1445 } else if (FD && FD->hasAttr<CUDAGlobalAttr>() &&
1446 GD.getKernelReferenceKind() == KernelReferenceKind::Stub) {
1447 Out << "__device_stub__" << II->getName();
1448 } else {
1449 Out << II->getName();
1450 }
1451 }
1452
1453 // Check if the module name hash should be appended for internal linkage
1454 // symbols. This should come before multi-version target suffixes are
1455 // appended. This is to keep the name and module hash suffix of the
1456 // internal linkage function together. The unique suffix should only be
1457 // added when name mangling is done to make sure that the final name can
1458 // be properly demangled. For example, for C functions without prototypes,
1459 // name mangling is not done and the unique suffix should not be appeneded
1460 // then.
1461 if (ShouldMangle && isUniqueInternalLinkageDecl(GD, CGM)) {
1462 assert(CGM.getCodeGenOpts().UniqueInternalLinkageNames &&
1463 "Hash computed when not explicitly requested");
1464 Out << CGM.getModuleNameHash();
1465 }
1466
1467 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
1468 if (FD->isMultiVersion() && !OmitMultiVersionMangling) {
1469 switch (FD->getMultiVersionKind()) {
1470 case MultiVersionKind::CPUDispatch:
1471 case MultiVersionKind::CPUSpecific:
1472 AppendCPUSpecificCPUDispatchMangling(CGM,
1473 FD->getAttr<CPUSpecificAttr>(),
1474 GD.getMultiVersionIndex(), Out);
1475 break;
1476 case MultiVersionKind::Target:
1477 AppendTargetMangling(CGM, FD->getAttr<TargetAttr>(), Out);
1478 break;
1479 case MultiVersionKind::TargetVersion:
1480 AppendTargetVersionMangling(CGM, FD->getAttr<TargetVersionAttr>(), Out);
1481 break;
1482 case MultiVersionKind::TargetClones:
1483 AppendTargetClonesMangling(CGM, FD->getAttr<TargetClonesAttr>(),
1484 GD.getMultiVersionIndex(), Out);
1485 break;
1486 case MultiVersionKind::None:
1487 llvm_unreachable("None multiversion type isn't valid here");
1488 }
1489 }
1490
1491 // Make unique name for device side static file-scope variable for HIP.
1492 if (CGM.getContext().shouldExternalize(ND) &&
1493 CGM.getLangOpts().GPURelocatableDeviceCode &&
1494 CGM.getLangOpts().CUDAIsDevice)
1495 CGM.printPostfixForExternalizedDecl(Out, ND);
1496
1497 return std::string(Out.str());
1498 }
1499
UpdateMultiVersionNames(GlobalDecl GD,const FunctionDecl * FD,StringRef & CurName)1500 void CodeGenModule::UpdateMultiVersionNames(GlobalDecl GD,
1501 const FunctionDecl *FD,
1502 StringRef &CurName) {
1503 if (!FD->isMultiVersion())
1504 return;
1505
1506 // Get the name of what this would be without the 'target' attribute. This
1507 // allows us to lookup the version that was emitted when this wasn't a
1508 // multiversion function.
1509 std::string NonTargetName =
1510 getMangledNameImpl(*this, GD, FD, /*OmitMultiVersionMangling=*/true);
1511 GlobalDecl OtherGD;
1512 if (lookupRepresentativeDecl(NonTargetName, OtherGD)) {
1513 assert(OtherGD.getCanonicalDecl()
1514 .getDecl()
1515 ->getAsFunction()
1516 ->isMultiVersion() &&
1517 "Other GD should now be a multiversioned function");
1518 // OtherFD is the version of this function that was mangled BEFORE
1519 // becoming a MultiVersion function. It potentially needs to be updated.
1520 const FunctionDecl *OtherFD = OtherGD.getCanonicalDecl()
1521 .getDecl()
1522 ->getAsFunction()
1523 ->getMostRecentDecl();
1524 std::string OtherName = getMangledNameImpl(*this, OtherGD, OtherFD);
1525 // This is so that if the initial version was already the 'default'
1526 // version, we don't try to update it.
1527 if (OtherName != NonTargetName) {
1528 // Remove instead of erase, since others may have stored the StringRef
1529 // to this.
1530 const auto ExistingRecord = Manglings.find(NonTargetName);
1531 if (ExistingRecord != std::end(Manglings))
1532 Manglings.remove(&(*ExistingRecord));
1533 auto Result = Manglings.insert(std::make_pair(OtherName, OtherGD));
1534 StringRef OtherNameRef = MangledDeclNames[OtherGD.getCanonicalDecl()] =
1535 Result.first->first();
1536 // If this is the current decl is being created, make sure we update the name.
1537 if (GD.getCanonicalDecl() == OtherGD.getCanonicalDecl())
1538 CurName = OtherNameRef;
1539 if (llvm::GlobalValue *Entry = GetGlobalValue(NonTargetName))
1540 Entry->setName(OtherName);
1541 }
1542 }
1543 }
1544
getMangledName(GlobalDecl GD)1545 StringRef CodeGenModule::getMangledName(GlobalDecl GD) {
1546 GlobalDecl CanonicalGD = GD.getCanonicalDecl();
1547
1548 // Some ABIs don't have constructor variants. Make sure that base and
1549 // complete constructors get mangled the same.
1550 if (const auto *CD = dyn_cast<CXXConstructorDecl>(CanonicalGD.getDecl())) {
1551 if (!getTarget().getCXXABI().hasConstructorVariants()) {
1552 CXXCtorType OrigCtorType = GD.getCtorType();
1553 assert(OrigCtorType == Ctor_Base || OrigCtorType == Ctor_Complete);
1554 if (OrigCtorType == Ctor_Base)
1555 CanonicalGD = GlobalDecl(CD, Ctor_Complete);
1556 }
1557 }
1558
1559 // In CUDA/HIP device compilation with -fgpu-rdc, the mangled name of a
1560 // static device variable depends on whether the variable is referenced by
1561 // a host or device host function. Therefore the mangled name cannot be
1562 // cached.
1563 if (!LangOpts.CUDAIsDevice || !getContext().mayExternalize(GD.getDecl())) {
1564 auto FoundName = MangledDeclNames.find(CanonicalGD);
1565 if (FoundName != MangledDeclNames.end())
1566 return FoundName->second;
1567 }
1568
1569 // Keep the first result in the case of a mangling collision.
1570 const auto *ND = cast<NamedDecl>(GD.getDecl());
1571 std::string MangledName = getMangledNameImpl(*this, GD, ND);
1572
1573 // Ensure either we have different ABIs between host and device compilations,
1574 // says host compilation following MSVC ABI but device compilation follows
1575 // Itanium C++ ABI or, if they follow the same ABI, kernel names after
1576 // mangling should be the same after name stubbing. The later checking is
1577 // very important as the device kernel name being mangled in host-compilation
1578 // is used to resolve the device binaries to be executed. Inconsistent naming
1579 // result in undefined behavior. Even though we cannot check that naming
1580 // directly between host- and device-compilations, the host- and
1581 // device-mangling in host compilation could help catching certain ones.
1582 assert(!isa<FunctionDecl>(ND) || !ND->hasAttr<CUDAGlobalAttr>() ||
1583 getContext().shouldExternalize(ND) || getLangOpts().CUDAIsDevice ||
1584 (getContext().getAuxTargetInfo() &&
1585 (getContext().getAuxTargetInfo()->getCXXABI() !=
1586 getContext().getTargetInfo().getCXXABI())) ||
1587 getCUDARuntime().getDeviceSideName(ND) ==
1588 getMangledNameImpl(
1589 *this,
1590 GD.getWithKernelReferenceKind(KernelReferenceKind::Kernel),
1591 ND));
1592
1593 auto Result = Manglings.insert(std::make_pair(MangledName, GD));
1594 return MangledDeclNames[CanonicalGD] = Result.first->first();
1595 }
1596
getBlockMangledName(GlobalDecl GD,const BlockDecl * BD)1597 StringRef CodeGenModule::getBlockMangledName(GlobalDecl GD,
1598 const BlockDecl *BD) {
1599 MangleContext &MangleCtx = getCXXABI().getMangleContext();
1600 const Decl *D = GD.getDecl();
1601
1602 SmallString<256> Buffer;
1603 llvm::raw_svector_ostream Out(Buffer);
1604 if (!D)
1605 MangleCtx.mangleGlobalBlock(BD,
1606 dyn_cast_or_null<VarDecl>(initializedGlobalDecl.getDecl()), Out);
1607 else if (const auto *CD = dyn_cast<CXXConstructorDecl>(D))
1608 MangleCtx.mangleCtorBlock(CD, GD.getCtorType(), BD, Out);
1609 else if (const auto *DD = dyn_cast<CXXDestructorDecl>(D))
1610 MangleCtx.mangleDtorBlock(DD, GD.getDtorType(), BD, Out);
1611 else
1612 MangleCtx.mangleBlock(cast<DeclContext>(D), BD, Out);
1613
1614 auto Result = Manglings.insert(std::make_pair(Out.str(), BD));
1615 return Result.first->first();
1616 }
1617
getMangledNameDecl(StringRef Name)1618 const GlobalDecl CodeGenModule::getMangledNameDecl(StringRef Name) {
1619 auto it = MangledDeclNames.begin();
1620 while (it != MangledDeclNames.end()) {
1621 if (it->second == Name)
1622 return it->first;
1623 it++;
1624 }
1625 return GlobalDecl();
1626 }
1627
GetGlobalValue(StringRef Name)1628 llvm::GlobalValue *CodeGenModule::GetGlobalValue(StringRef Name) {
1629 return getModule().getNamedValue(Name);
1630 }
1631
1632 /// AddGlobalCtor - Add a function to the list that will be called before
1633 /// main() runs.
AddGlobalCtor(llvm::Function * Ctor,int Priority,unsigned LexOrder,llvm::Constant * AssociatedData)1634 void CodeGenModule::AddGlobalCtor(llvm::Function *Ctor, int Priority,
1635 unsigned LexOrder,
1636 llvm::Constant *AssociatedData) {
1637 // FIXME: Type coercion of void()* types.
1638 GlobalCtors.push_back(Structor(Priority, LexOrder, Ctor, AssociatedData));
1639 }
1640
1641 /// AddGlobalDtor - Add a function to the list that will be called
1642 /// when the module is unloaded.
AddGlobalDtor(llvm::Function * Dtor,int Priority,bool IsDtorAttrFunc)1643 void CodeGenModule::AddGlobalDtor(llvm::Function *Dtor, int Priority,
1644 bool IsDtorAttrFunc) {
1645 if (CodeGenOpts.RegisterGlobalDtorsWithAtExit &&
1646 (!getContext().getTargetInfo().getTriple().isOSAIX() || IsDtorAttrFunc)) {
1647 DtorsUsingAtExit[Priority].push_back(Dtor);
1648 return;
1649 }
1650
1651 // FIXME: Type coercion of void()* types.
1652 GlobalDtors.push_back(Structor(Priority, ~0U, Dtor, nullptr));
1653 }
1654
EmitCtorList(CtorList & Fns,const char * GlobalName)1655 void CodeGenModule::EmitCtorList(CtorList &Fns, const char *GlobalName) {
1656 if (Fns.empty()) return;
1657
1658 // Ctor function type is void()*.
1659 llvm::FunctionType* CtorFTy = llvm::FunctionType::get(VoidTy, false);
1660 llvm::Type *CtorPFTy = llvm::PointerType::get(CtorFTy,
1661 TheModule.getDataLayout().getProgramAddressSpace());
1662
1663 // Get the type of a ctor entry, { i32, void ()*, i8* }.
1664 llvm::StructType *CtorStructTy = llvm::StructType::get(
1665 Int32Ty, CtorPFTy, VoidPtrTy);
1666
1667 // Construct the constructor and destructor arrays.
1668 ConstantInitBuilder builder(*this);
1669 auto ctors = builder.beginArray(CtorStructTy);
1670 for (const auto &I : Fns) {
1671 auto ctor = ctors.beginStruct(CtorStructTy);
1672 ctor.addInt(Int32Ty, I.Priority);
1673 ctor.add(llvm::ConstantExpr::getBitCast(I.Initializer, CtorPFTy));
1674 if (I.AssociatedData)
1675 ctor.add(llvm::ConstantExpr::getBitCast(I.AssociatedData, VoidPtrTy));
1676 else
1677 ctor.addNullPointer(VoidPtrTy);
1678 ctor.finishAndAddTo(ctors);
1679 }
1680
1681 auto list =
1682 ctors.finishAndCreateGlobal(GlobalName, getPointerAlign(),
1683 /*constant*/ false,
1684 llvm::GlobalValue::AppendingLinkage);
1685
1686 // The LTO linker doesn't seem to like it when we set an alignment
1687 // on appending variables. Take it off as a workaround.
1688 list->setAlignment(std::nullopt);
1689
1690 Fns.clear();
1691 }
1692
1693 llvm::GlobalValue::LinkageTypes
getFunctionLinkage(GlobalDecl GD)1694 CodeGenModule::getFunctionLinkage(GlobalDecl GD) {
1695 const auto *D = cast<FunctionDecl>(GD.getDecl());
1696
1697 GVALinkage Linkage = getContext().GetGVALinkageForFunction(D);
1698
1699 if (const auto *Dtor = dyn_cast<CXXDestructorDecl>(D))
1700 return getCXXABI().getCXXDestructorLinkage(Linkage, Dtor, GD.getDtorType());
1701
1702 if (isa<CXXConstructorDecl>(D) &&
1703 cast<CXXConstructorDecl>(D)->isInheritingConstructor() &&
1704 Context.getTargetInfo().getCXXABI().isMicrosoft()) {
1705 // Our approach to inheriting constructors is fundamentally different from
1706 // that used by the MS ABI, so keep our inheriting constructor thunks
1707 // internal rather than trying to pick an unambiguous mangling for them.
1708 return llvm::GlobalValue::InternalLinkage;
1709 }
1710
1711 return getLLVMLinkageForDeclarator(D, Linkage, /*IsConstantVariable=*/false);
1712 }
1713
CreateCrossDsoCfiTypeId(llvm::Metadata * MD)1714 llvm::ConstantInt *CodeGenModule::CreateCrossDsoCfiTypeId(llvm::Metadata *MD) {
1715 llvm::MDString *MDS = dyn_cast<llvm::MDString>(MD);
1716 if (!MDS) return nullptr;
1717
1718 return llvm::ConstantInt::get(Int64Ty, llvm::MD5Hash(MDS->getString()));
1719 }
1720
CreateKCFITypeId(QualType T)1721 llvm::ConstantInt *CodeGenModule::CreateKCFITypeId(QualType T) {
1722 if (auto *FnType = T->getAs<FunctionProtoType>())
1723 T = getContext().getFunctionType(
1724 FnType->getReturnType(), FnType->getParamTypes(),
1725 FnType->getExtProtoInfo().withExceptionSpec(EST_None));
1726
1727 std::string OutName;
1728 llvm::raw_string_ostream Out(OutName);
1729 getCXXABI().getMangleContext().mangleTypeName(T, Out);
1730
1731 return llvm::ConstantInt::get(Int32Ty,
1732 static_cast<uint32_t>(llvm::xxHash64(OutName)));
1733 }
1734
SetLLVMFunctionAttributes(GlobalDecl GD,const CGFunctionInfo & Info,llvm::Function * F,bool IsThunk)1735 void CodeGenModule::SetLLVMFunctionAttributes(GlobalDecl GD,
1736 const CGFunctionInfo &Info,
1737 llvm::Function *F, bool IsThunk) {
1738 unsigned CallingConv;
1739 llvm::AttributeList PAL;
1740 ConstructAttributeList(F->getName(), Info, GD, PAL, CallingConv,
1741 /*AttrOnCallSite=*/false, IsThunk);
1742 F->setAttributes(PAL);
1743 F->setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv));
1744 }
1745
removeImageAccessQualifier(std::string & TyName)1746 static void removeImageAccessQualifier(std::string& TyName) {
1747 std::string ReadOnlyQual("__read_only");
1748 std::string::size_type ReadOnlyPos = TyName.find(ReadOnlyQual);
1749 if (ReadOnlyPos != std::string::npos)
1750 // "+ 1" for the space after access qualifier.
1751 TyName.erase(ReadOnlyPos, ReadOnlyQual.size() + 1);
1752 else {
1753 std::string WriteOnlyQual("__write_only");
1754 std::string::size_type WriteOnlyPos = TyName.find(WriteOnlyQual);
1755 if (WriteOnlyPos != std::string::npos)
1756 TyName.erase(WriteOnlyPos, WriteOnlyQual.size() + 1);
1757 else {
1758 std::string ReadWriteQual("__read_write");
1759 std::string::size_type ReadWritePos = TyName.find(ReadWriteQual);
1760 if (ReadWritePos != std::string::npos)
1761 TyName.erase(ReadWritePos, ReadWriteQual.size() + 1);
1762 }
1763 }
1764 }
1765
1766 // Returns the address space id that should be produced to the
1767 // kernel_arg_addr_space metadata. This is always fixed to the ids
1768 // as specified in the SPIR 2.0 specification in order to differentiate
1769 // for example in clGetKernelArgInfo() implementation between the address
1770 // spaces with targets without unique mapping to the OpenCL address spaces
1771 // (basically all single AS CPUs).
ArgInfoAddressSpace(LangAS AS)1772 static unsigned ArgInfoAddressSpace(LangAS AS) {
1773 switch (AS) {
1774 case LangAS::opencl_global:
1775 return 1;
1776 case LangAS::opencl_constant:
1777 return 2;
1778 case LangAS::opencl_local:
1779 return 3;
1780 case LangAS::opencl_generic:
1781 return 4; // Not in SPIR 2.0 specs.
1782 case LangAS::opencl_global_device:
1783 return 5;
1784 case LangAS::opencl_global_host:
1785 return 6;
1786 default:
1787 return 0; // Assume private.
1788 }
1789 }
1790
GenKernelArgMetadata(llvm::Function * Fn,const FunctionDecl * FD,CodeGenFunction * CGF)1791 void CodeGenModule::GenKernelArgMetadata(llvm::Function *Fn,
1792 const FunctionDecl *FD,
1793 CodeGenFunction *CGF) {
1794 assert(((FD && CGF) || (!FD && !CGF)) &&
1795 "Incorrect use - FD and CGF should either be both null or not!");
1796 // Create MDNodes that represent the kernel arg metadata.
1797 // Each MDNode is a list in the form of "key", N number of values which is
1798 // the same number of values as their are kernel arguments.
1799
1800 const PrintingPolicy &Policy = Context.getPrintingPolicy();
1801
1802 // MDNode for the kernel argument address space qualifiers.
1803 SmallVector<llvm::Metadata *, 8> addressQuals;
1804
1805 // MDNode for the kernel argument access qualifiers (images only).
1806 SmallVector<llvm::Metadata *, 8> accessQuals;
1807
1808 // MDNode for the kernel argument type names.
1809 SmallVector<llvm::Metadata *, 8> argTypeNames;
1810
1811 // MDNode for the kernel argument base type names.
1812 SmallVector<llvm::Metadata *, 8> argBaseTypeNames;
1813
1814 // MDNode for the kernel argument type qualifiers.
1815 SmallVector<llvm::Metadata *, 8> argTypeQuals;
1816
1817 // MDNode for the kernel argument names.
1818 SmallVector<llvm::Metadata *, 8> argNames;
1819
1820 if (FD && CGF)
1821 for (unsigned i = 0, e = FD->getNumParams(); i != e; ++i) {
1822 const ParmVarDecl *parm = FD->getParamDecl(i);
1823 // Get argument name.
1824 argNames.push_back(llvm::MDString::get(VMContext, parm->getName()));
1825
1826 if (!getLangOpts().OpenCL)
1827 continue;
1828 QualType ty = parm->getType();
1829 std::string typeQuals;
1830
1831 // Get image and pipe access qualifier:
1832 if (ty->isImageType() || ty->isPipeType()) {
1833 const Decl *PDecl = parm;
1834 if (const auto *TD = ty->getAs<TypedefType>())
1835 PDecl = TD->getDecl();
1836 const OpenCLAccessAttr *A = PDecl->getAttr<OpenCLAccessAttr>();
1837 if (A && A->isWriteOnly())
1838 accessQuals.push_back(llvm::MDString::get(VMContext, "write_only"));
1839 else if (A && A->isReadWrite())
1840 accessQuals.push_back(llvm::MDString::get(VMContext, "read_write"));
1841 else
1842 accessQuals.push_back(llvm::MDString::get(VMContext, "read_only"));
1843 } else
1844 accessQuals.push_back(llvm::MDString::get(VMContext, "none"));
1845
1846 auto getTypeSpelling = [&](QualType Ty) {
1847 auto typeName = Ty.getUnqualifiedType().getAsString(Policy);
1848
1849 if (Ty.isCanonical()) {
1850 StringRef typeNameRef = typeName;
1851 // Turn "unsigned type" to "utype"
1852 if (typeNameRef.consume_front("unsigned "))
1853 return std::string("u") + typeNameRef.str();
1854 if (typeNameRef.consume_front("signed "))
1855 return typeNameRef.str();
1856 }
1857
1858 return typeName;
1859 };
1860
1861 if (ty->isPointerType()) {
1862 QualType pointeeTy = ty->getPointeeType();
1863
1864 // Get address qualifier.
1865 addressQuals.push_back(
1866 llvm::ConstantAsMetadata::get(CGF->Builder.getInt32(
1867 ArgInfoAddressSpace(pointeeTy.getAddressSpace()))));
1868
1869 // Get argument type name.
1870 std::string typeName = getTypeSpelling(pointeeTy) + "*";
1871 std::string baseTypeName =
1872 getTypeSpelling(pointeeTy.getCanonicalType()) + "*";
1873 argTypeNames.push_back(llvm::MDString::get(VMContext, typeName));
1874 argBaseTypeNames.push_back(
1875 llvm::MDString::get(VMContext, baseTypeName));
1876
1877 // Get argument type qualifiers:
1878 if (ty.isRestrictQualified())
1879 typeQuals = "restrict";
1880 if (pointeeTy.isConstQualified() ||
1881 (pointeeTy.getAddressSpace() == LangAS::opencl_constant))
1882 typeQuals += typeQuals.empty() ? "const" : " const";
1883 if (pointeeTy.isVolatileQualified())
1884 typeQuals += typeQuals.empty() ? "volatile" : " volatile";
1885 } else {
1886 uint32_t AddrSpc = 0;
1887 bool isPipe = ty->isPipeType();
1888 if (ty->isImageType() || isPipe)
1889 AddrSpc = ArgInfoAddressSpace(LangAS::opencl_global);
1890
1891 addressQuals.push_back(
1892 llvm::ConstantAsMetadata::get(CGF->Builder.getInt32(AddrSpc)));
1893
1894 // Get argument type name.
1895 ty = isPipe ? ty->castAs<PipeType>()->getElementType() : ty;
1896 std::string typeName = getTypeSpelling(ty);
1897 std::string baseTypeName = getTypeSpelling(ty.getCanonicalType());
1898
1899 // Remove access qualifiers on images
1900 // (as they are inseparable from type in clang implementation,
1901 // but OpenCL spec provides a special query to get access qualifier
1902 // via clGetKernelArgInfo with CL_KERNEL_ARG_ACCESS_QUALIFIER):
1903 if (ty->isImageType()) {
1904 removeImageAccessQualifier(typeName);
1905 removeImageAccessQualifier(baseTypeName);
1906 }
1907
1908 argTypeNames.push_back(llvm::MDString::get(VMContext, typeName));
1909 argBaseTypeNames.push_back(
1910 llvm::MDString::get(VMContext, baseTypeName));
1911
1912 if (isPipe)
1913 typeQuals = "pipe";
1914 }
1915 argTypeQuals.push_back(llvm::MDString::get(VMContext, typeQuals));
1916 }
1917
1918 if (getLangOpts().OpenCL) {
1919 Fn->setMetadata("kernel_arg_addr_space",
1920 llvm::MDNode::get(VMContext, addressQuals));
1921 Fn->setMetadata("kernel_arg_access_qual",
1922 llvm::MDNode::get(VMContext, accessQuals));
1923 Fn->setMetadata("kernel_arg_type",
1924 llvm::MDNode::get(VMContext, argTypeNames));
1925 Fn->setMetadata("kernel_arg_base_type",
1926 llvm::MDNode::get(VMContext, argBaseTypeNames));
1927 Fn->setMetadata("kernel_arg_type_qual",
1928 llvm::MDNode::get(VMContext, argTypeQuals));
1929 }
1930 if (getCodeGenOpts().EmitOpenCLArgMetadata ||
1931 getCodeGenOpts().HIPSaveKernelArgName)
1932 Fn->setMetadata("kernel_arg_name",
1933 llvm::MDNode::get(VMContext, argNames));
1934 }
1935
1936 /// Determines whether the language options require us to model
1937 /// unwind exceptions. We treat -fexceptions as mandating this
1938 /// except under the fragile ObjC ABI with only ObjC exceptions
1939 /// enabled. This means, for example, that C with -fexceptions
1940 /// enables this.
hasUnwindExceptions(const LangOptions & LangOpts)1941 static bool hasUnwindExceptions(const LangOptions &LangOpts) {
1942 // If exceptions are completely disabled, obviously this is false.
1943 if (!LangOpts.Exceptions) return false;
1944
1945 // If C++ exceptions are enabled, this is true.
1946 if (LangOpts.CXXExceptions) return true;
1947
1948 // If ObjC exceptions are enabled, this depends on the ABI.
1949 if (LangOpts.ObjCExceptions) {
1950 return LangOpts.ObjCRuntime.hasUnwindExceptions();
1951 }
1952
1953 return true;
1954 }
1955
requiresMemberFunctionPointerTypeMetadata(CodeGenModule & CGM,const CXXMethodDecl * MD)1956 static bool requiresMemberFunctionPointerTypeMetadata(CodeGenModule &CGM,
1957 const CXXMethodDecl *MD) {
1958 // Check that the type metadata can ever actually be used by a call.
1959 if (!CGM.getCodeGenOpts().LTOUnit ||
1960 !CGM.HasHiddenLTOVisibility(MD->getParent()))
1961 return false;
1962
1963 // Only functions whose address can be taken with a member function pointer
1964 // need this sort of type metadata.
1965 return !MD->isStatic() && !MD->isVirtual() && !isa<CXXConstructorDecl>(MD) &&
1966 !isa<CXXDestructorDecl>(MD);
1967 }
1968
1969 std::vector<const CXXRecordDecl *>
getMostBaseClasses(const CXXRecordDecl * RD)1970 CodeGenModule::getMostBaseClasses(const CXXRecordDecl *RD) {
1971 llvm::SetVector<const CXXRecordDecl *> MostBases;
1972
1973 std::function<void (const CXXRecordDecl *)> CollectMostBases;
1974 CollectMostBases = [&](const CXXRecordDecl *RD) {
1975 if (RD->getNumBases() == 0)
1976 MostBases.insert(RD);
1977 for (const CXXBaseSpecifier &B : RD->bases())
1978 CollectMostBases(B.getType()->getAsCXXRecordDecl());
1979 };
1980 CollectMostBases(RD);
1981 return MostBases.takeVector();
1982 }
1983
1984 llvm::GlobalVariable *
GetOrCreateRTTIProxyGlobalVariable(llvm::Constant * Addr)1985 CodeGenModule::GetOrCreateRTTIProxyGlobalVariable(llvm::Constant *Addr) {
1986 auto It = RTTIProxyMap.find(Addr);
1987 if (It != RTTIProxyMap.end())
1988 return It->second;
1989
1990 auto *FTRTTIProxy = new llvm::GlobalVariable(
1991 TheModule, Addr->getType(),
1992 /*isConstant=*/true, llvm::GlobalValue::PrivateLinkage, Addr,
1993 "__llvm_rtti_proxy");
1994 FTRTTIProxy->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
1995
1996 RTTIProxyMap[Addr] = FTRTTIProxy;
1997 return FTRTTIProxy;
1998 }
1999
SetLLVMFunctionAttributesForDefinition(const Decl * D,llvm::Function * F)2000 void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
2001 llvm::Function *F) {
2002 llvm::AttrBuilder B(F->getContext());
2003
2004 if ((!D || !D->hasAttr<NoUwtableAttr>()) && CodeGenOpts.UnwindTables)
2005 B.addUWTableAttr(llvm::UWTableKind(CodeGenOpts.UnwindTables));
2006
2007 if (CodeGenOpts.StackClashProtector)
2008 B.addAttribute("probe-stack", "inline-asm");
2009
2010 if (!hasUnwindExceptions(LangOpts))
2011 B.addAttribute(llvm::Attribute::NoUnwind);
2012
2013 if (D && D->hasAttr<NoStackProtectorAttr>())
2014 ; // Do nothing.
2015 else if (D && D->hasAttr<StrictGuardStackCheckAttr>() &&
2016 LangOpts.getStackProtector() == LangOptions::SSPOn)
2017 B.addAttribute(llvm::Attribute::StackProtectStrong);
2018 else if (LangOpts.getStackProtector() == LangOptions::SSPOn)
2019 B.addAttribute(llvm::Attribute::StackProtect);
2020 else if (LangOpts.getStackProtector() == LangOptions::SSPStrong)
2021 B.addAttribute(llvm::Attribute::StackProtectStrong);
2022 else if (LangOpts.getStackProtector() == LangOptions::SSPReq)
2023 B.addAttribute(llvm::Attribute::StackProtectReq);
2024
2025 if (!D) {
2026 // If we don't have a declaration to control inlining, the function isn't
2027 // explicitly marked as alwaysinline for semantic reasons, and inlining is
2028 // disabled, mark the function as noinline.
2029 if (!F->hasFnAttribute(llvm::Attribute::AlwaysInline) &&
2030 CodeGenOpts.getInlining() == CodeGenOptions::OnlyAlwaysInlining)
2031 B.addAttribute(llvm::Attribute::NoInline);
2032
2033 F->addFnAttrs(B);
2034 return;
2035 }
2036
2037 // Track whether we need to add the optnone LLVM attribute,
2038 // starting with the default for this optimization level.
2039 bool ShouldAddOptNone =
2040 !CodeGenOpts.DisableO0ImplyOptNone && CodeGenOpts.OptimizationLevel == 0;
2041 // We can't add optnone in the following cases, it won't pass the verifier.
2042 ShouldAddOptNone &= !D->hasAttr<MinSizeAttr>();
2043 ShouldAddOptNone &= !D->hasAttr<AlwaysInlineAttr>();
2044
2045 // Add optnone, but do so only if the function isn't always_inline.
2046 if ((ShouldAddOptNone || D->hasAttr<OptimizeNoneAttr>()) &&
2047 !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) {
2048 B.addAttribute(llvm::Attribute::OptimizeNone);
2049
2050 // OptimizeNone implies noinline; we should not be inlining such functions.
2051 B.addAttribute(llvm::Attribute::NoInline);
2052
2053 // We still need to handle naked functions even though optnone subsumes
2054 // much of their semantics.
2055 if (D->hasAttr<NakedAttr>())
2056 B.addAttribute(llvm::Attribute::Naked);
2057
2058 // OptimizeNone wins over OptimizeForSize and MinSize.
2059 F->removeFnAttr(llvm::Attribute::OptimizeForSize);
2060 F->removeFnAttr(llvm::Attribute::MinSize);
2061 } else if (D->hasAttr<NakedAttr>()) {
2062 // Naked implies noinline: we should not be inlining such functions.
2063 B.addAttribute(llvm::Attribute::Naked);
2064 B.addAttribute(llvm::Attribute::NoInline);
2065 } else if (D->hasAttr<NoDuplicateAttr>()) {
2066 B.addAttribute(llvm::Attribute::NoDuplicate);
2067 } else if (D->hasAttr<NoInlineAttr>() && !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) {
2068 // Add noinline if the function isn't always_inline.
2069 B.addAttribute(llvm::Attribute::NoInline);
2070 } else if (D->hasAttr<AlwaysInlineAttr>() &&
2071 !F->hasFnAttribute(llvm::Attribute::NoInline)) {
2072 // (noinline wins over always_inline, and we can't specify both in IR)
2073 B.addAttribute(llvm::Attribute::AlwaysInline);
2074 } else if (CodeGenOpts.getInlining() == CodeGenOptions::OnlyAlwaysInlining) {
2075 // If we're not inlining, then force everything that isn't always_inline to
2076 // carry an explicit noinline attribute.
2077 if (!F->hasFnAttribute(llvm::Attribute::AlwaysInline))
2078 B.addAttribute(llvm::Attribute::NoInline);
2079 } else {
2080 // Otherwise, propagate the inline hint attribute and potentially use its
2081 // absence to mark things as noinline.
2082 if (auto *FD = dyn_cast<FunctionDecl>(D)) {
2083 // Search function and template pattern redeclarations for inline.
2084 auto CheckForInline = [](const FunctionDecl *FD) {
2085 auto CheckRedeclForInline = [](const FunctionDecl *Redecl) {
2086 return Redecl->isInlineSpecified();
2087 };
2088 if (any_of(FD->redecls(), CheckRedeclForInline))
2089 return true;
2090 const FunctionDecl *Pattern = FD->getTemplateInstantiationPattern();
2091 if (!Pattern)
2092 return false;
2093 return any_of(Pattern->redecls(), CheckRedeclForInline);
2094 };
2095 if (CheckForInline(FD)) {
2096 B.addAttribute(llvm::Attribute::InlineHint);
2097 } else if (CodeGenOpts.getInlining() ==
2098 CodeGenOptions::OnlyHintInlining &&
2099 !FD->isInlined() &&
2100 !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) {
2101 B.addAttribute(llvm::Attribute::NoInline);
2102 }
2103 }
2104 }
2105
2106 // Add other optimization related attributes if we are optimizing this
2107 // function.
2108 if (!D->hasAttr<OptimizeNoneAttr>()) {
2109 if (D->hasAttr<ColdAttr>()) {
2110 if (!ShouldAddOptNone)
2111 B.addAttribute(llvm::Attribute::OptimizeForSize);
2112 B.addAttribute(llvm::Attribute::Cold);
2113 }
2114 if (D->hasAttr<HotAttr>())
2115 B.addAttribute(llvm::Attribute::Hot);
2116 if (D->hasAttr<MinSizeAttr>())
2117 B.addAttribute(llvm::Attribute::MinSize);
2118 }
2119
2120 F->addFnAttrs(B);
2121
2122 unsigned alignment = D->getMaxAlignment() / Context.getCharWidth();
2123 if (alignment)
2124 F->setAlignment(llvm::Align(alignment));
2125
2126 if (!D->hasAttr<AlignedAttr>())
2127 if (LangOpts.FunctionAlignment)
2128 F->setAlignment(llvm::Align(1ull << LangOpts.FunctionAlignment));
2129
2130 // Some C++ ABIs require 2-byte alignment for member functions, in order to
2131 // reserve a bit for differentiating between virtual and non-virtual member
2132 // functions. If the current target's C++ ABI requires this and this is a
2133 // member function, set its alignment accordingly.
2134 if (getTarget().getCXXABI().areMemberFunctionsAligned()) {
2135 if (F->getAlignment() < 2 && isa<CXXMethodDecl>(D))
2136 F->setAlignment(llvm::Align(2));
2137 }
2138
2139 // In the cross-dso CFI mode with canonical jump tables, we want !type
2140 // attributes on definitions only.
2141 if (CodeGenOpts.SanitizeCfiCrossDso &&
2142 CodeGenOpts.SanitizeCfiCanonicalJumpTables) {
2143 if (auto *FD = dyn_cast<FunctionDecl>(D)) {
2144 // Skip available_externally functions. They won't be codegen'ed in the
2145 // current module anyway.
2146 if (getContext().GetGVALinkageForFunction(FD) != GVA_AvailableExternally)
2147 CreateFunctionTypeMetadataForIcall(FD, F);
2148 }
2149 }
2150
2151 // Emit type metadata on member functions for member function pointer checks.
2152 // These are only ever necessary on definitions; we're guaranteed that the
2153 // definition will be present in the LTO unit as a result of LTO visibility.
2154 auto *MD = dyn_cast<CXXMethodDecl>(D);
2155 if (MD && requiresMemberFunctionPointerTypeMetadata(*this, MD)) {
2156 for (const CXXRecordDecl *Base : getMostBaseClasses(MD->getParent())) {
2157 llvm::Metadata *Id =
2158 CreateMetadataIdentifierForType(Context.getMemberPointerType(
2159 MD->getType(), Context.getRecordType(Base).getTypePtr()));
2160 F->addTypeMetadata(0, Id);
2161 }
2162 }
2163 }
2164
setLLVMFunctionFEnvAttributes(const FunctionDecl * D,llvm::Function * F)2165 void CodeGenModule::setLLVMFunctionFEnvAttributes(const FunctionDecl *D,
2166 llvm::Function *F) {
2167 if (D->hasAttr<StrictFPAttr>()) {
2168 llvm::AttrBuilder FuncAttrs(F->getContext());
2169 FuncAttrs.addAttribute("strictfp");
2170 F->addFnAttrs(FuncAttrs);
2171 }
2172 }
2173
SetCommonAttributes(GlobalDecl GD,llvm::GlobalValue * GV)2174 void CodeGenModule::SetCommonAttributes(GlobalDecl GD, llvm::GlobalValue *GV) {
2175 const Decl *D = GD.getDecl();
2176 if (isa_and_nonnull<NamedDecl>(D))
2177 setGVProperties(GV, GD);
2178 else
2179 GV->setVisibility(llvm::GlobalValue::DefaultVisibility);
2180
2181 if (D && D->hasAttr<UsedAttr>())
2182 addUsedOrCompilerUsedGlobal(GV);
2183
2184 if (CodeGenOpts.KeepStaticConsts && D && isa<VarDecl>(D)) {
2185 const auto *VD = cast<VarDecl>(D);
2186 if (VD->getType().isConstQualified() &&
2187 VD->getStorageDuration() == SD_Static)
2188 addUsedOrCompilerUsedGlobal(GV);
2189 }
2190 }
2191
GetCPUAndFeaturesAttributes(GlobalDecl GD,llvm::AttrBuilder & Attrs)2192 bool CodeGenModule::GetCPUAndFeaturesAttributes(GlobalDecl GD,
2193 llvm::AttrBuilder &Attrs) {
2194 // Add target-cpu and target-features attributes to functions. If
2195 // we have a decl for the function and it has a target attribute then
2196 // parse that and add it to the feature set.
2197 StringRef TargetCPU = getTarget().getTargetOpts().CPU;
2198 StringRef TuneCPU = getTarget().getTargetOpts().TuneCPU;
2199 std::vector<std::string> Features;
2200 const auto *FD = dyn_cast_or_null<FunctionDecl>(GD.getDecl());
2201 FD = FD ? FD->getMostRecentDecl() : FD;
2202 const auto *TD = FD ? FD->getAttr<TargetAttr>() : nullptr;
2203 const auto *TV = FD ? FD->getAttr<TargetVersionAttr>() : nullptr;
2204 assert((!TD || !TV) && "both target_version and target specified");
2205 const auto *SD = FD ? FD->getAttr<CPUSpecificAttr>() : nullptr;
2206 const auto *TC = FD ? FD->getAttr<TargetClonesAttr>() : nullptr;
2207 bool AddedAttr = false;
2208 if (TD || TV || SD || TC) {
2209 llvm::StringMap<bool> FeatureMap;
2210 getContext().getFunctionFeatureMap(FeatureMap, GD);
2211
2212 // Produce the canonical string for this set of features.
2213 for (const llvm::StringMap<bool>::value_type &Entry : FeatureMap)
2214 Features.push_back((Entry.getValue() ? "+" : "-") + Entry.getKey().str());
2215
2216 // Now add the target-cpu and target-features to the function.
2217 // While we populated the feature map above, we still need to
2218 // get and parse the target attribute so we can get the cpu for
2219 // the function.
2220 if (TD) {
2221 ParsedTargetAttr ParsedAttr =
2222 Target.parseTargetAttr(TD->getFeaturesStr());
2223 if (!ParsedAttr.CPU.empty() &&
2224 getTarget().isValidCPUName(ParsedAttr.CPU)) {
2225 TargetCPU = ParsedAttr.CPU;
2226 TuneCPU = ""; // Clear the tune CPU.
2227 }
2228 if (!ParsedAttr.Tune.empty() &&
2229 getTarget().isValidCPUName(ParsedAttr.Tune))
2230 TuneCPU = ParsedAttr.Tune;
2231 }
2232
2233 if (SD) {
2234 // Apply the given CPU name as the 'tune-cpu' so that the optimizer can
2235 // favor this processor.
2236 TuneCPU = getTarget().getCPUSpecificTuneName(
2237 SD->getCPUName(GD.getMultiVersionIndex())->getName());
2238 }
2239 } else {
2240 // Otherwise just add the existing target cpu and target features to the
2241 // function.
2242 Features = getTarget().getTargetOpts().Features;
2243 }
2244
2245 if (!TargetCPU.empty()) {
2246 Attrs.addAttribute("target-cpu", TargetCPU);
2247 AddedAttr = true;
2248 }
2249 if (!TuneCPU.empty()) {
2250 Attrs.addAttribute("tune-cpu", TuneCPU);
2251 AddedAttr = true;
2252 }
2253 if (!Features.empty()) {
2254 llvm::sort(Features);
2255 Attrs.addAttribute("target-features", llvm::join(Features, ","));
2256 AddedAttr = true;
2257 }
2258
2259 return AddedAttr;
2260 }
2261
setNonAliasAttributes(GlobalDecl GD,llvm::GlobalObject * GO)2262 void CodeGenModule::setNonAliasAttributes(GlobalDecl GD,
2263 llvm::GlobalObject *GO) {
2264 const Decl *D = GD.getDecl();
2265 SetCommonAttributes(GD, GO);
2266
2267 if (D) {
2268 if (auto *GV = dyn_cast<llvm::GlobalVariable>(GO)) {
2269 if (D->hasAttr<RetainAttr>())
2270 addUsedGlobal(GV);
2271 if (auto *SA = D->getAttr<PragmaClangBSSSectionAttr>())
2272 GV->addAttribute("bss-section", SA->getName());
2273 if (auto *SA = D->getAttr<PragmaClangDataSectionAttr>())
2274 GV->addAttribute("data-section", SA->getName());
2275 if (auto *SA = D->getAttr<PragmaClangRodataSectionAttr>())
2276 GV->addAttribute("rodata-section", SA->getName());
2277 if (auto *SA = D->getAttr<PragmaClangRelroSectionAttr>())
2278 GV->addAttribute("relro-section", SA->getName());
2279 }
2280
2281 if (auto *F = dyn_cast<llvm::Function>(GO)) {
2282 if (D->hasAttr<RetainAttr>())
2283 addUsedGlobal(F);
2284 if (auto *SA = D->getAttr<PragmaClangTextSectionAttr>())
2285 if (!D->getAttr<SectionAttr>())
2286 F->addFnAttr("implicit-section-name", SA->getName());
2287
2288 llvm::AttrBuilder Attrs(F->getContext());
2289 if (GetCPUAndFeaturesAttributes(GD, Attrs)) {
2290 // We know that GetCPUAndFeaturesAttributes will always have the
2291 // newest set, since it has the newest possible FunctionDecl, so the
2292 // new ones should replace the old.
2293 llvm::AttributeMask RemoveAttrs;
2294 RemoveAttrs.addAttribute("target-cpu");
2295 RemoveAttrs.addAttribute("target-features");
2296 RemoveAttrs.addAttribute("tune-cpu");
2297 F->removeFnAttrs(RemoveAttrs);
2298 F->addFnAttrs(Attrs);
2299 }
2300 }
2301
2302 if (const auto *CSA = D->getAttr<CodeSegAttr>())
2303 GO->setSection(CSA->getName());
2304 else if (const auto *SA = D->getAttr<SectionAttr>())
2305 GO->setSection(SA->getName());
2306 }
2307
2308 getTargetCodeGenInfo().setTargetAttributes(D, GO, *this);
2309 }
2310
SetInternalFunctionAttributes(GlobalDecl GD,llvm::Function * F,const CGFunctionInfo & FI)2311 void CodeGenModule::SetInternalFunctionAttributes(GlobalDecl GD,
2312 llvm::Function *F,
2313 const CGFunctionInfo &FI) {
2314 const Decl *D = GD.getDecl();
2315 SetLLVMFunctionAttributes(GD, FI, F, /*IsThunk=*/false);
2316 SetLLVMFunctionAttributesForDefinition(D, F);
2317
2318 F->setLinkage(llvm::Function::InternalLinkage);
2319
2320 setNonAliasAttributes(GD, F);
2321 }
2322
setLinkageForGV(llvm::GlobalValue * GV,const NamedDecl * ND)2323 static void setLinkageForGV(llvm::GlobalValue *GV, const NamedDecl *ND) {
2324 // Set linkage and visibility in case we never see a definition.
2325 LinkageInfo LV = ND->getLinkageAndVisibility();
2326 // Don't set internal linkage on declarations.
2327 // "extern_weak" is overloaded in LLVM; we probably should have
2328 // separate linkage types for this.
2329 if (isExternallyVisible(LV.getLinkage()) &&
2330 (ND->hasAttr<WeakAttr>() || ND->isWeakImported()))
2331 GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage);
2332 }
2333
CreateFunctionTypeMetadataForIcall(const FunctionDecl * FD,llvm::Function * F)2334 void CodeGenModule::CreateFunctionTypeMetadataForIcall(const FunctionDecl *FD,
2335 llvm::Function *F) {
2336 // Only if we are checking indirect calls.
2337 if (!LangOpts.Sanitize.has(SanitizerKind::CFIICall))
2338 return;
2339
2340 // Non-static class methods are handled via vtable or member function pointer
2341 // checks elsewhere.
2342 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic())
2343 return;
2344
2345 llvm::Metadata *MD = CreateMetadataIdentifierForType(FD->getType());
2346 F->addTypeMetadata(0, MD);
2347 F->addTypeMetadata(0, CreateMetadataIdentifierGeneralized(FD->getType()));
2348
2349 // Emit a hash-based bit set entry for cross-DSO calls.
2350 if (CodeGenOpts.SanitizeCfiCrossDso)
2351 if (auto CrossDsoTypeId = CreateCrossDsoCfiTypeId(MD))
2352 F->addTypeMetadata(0, llvm::ConstantAsMetadata::get(CrossDsoTypeId));
2353 }
2354
setKCFIType(const FunctionDecl * FD,llvm::Function * F)2355 void CodeGenModule::setKCFIType(const FunctionDecl *FD, llvm::Function *F) {
2356 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic())
2357 return;
2358
2359 llvm::LLVMContext &Ctx = F->getContext();
2360 llvm::MDBuilder MDB(Ctx);
2361 F->setMetadata(llvm::LLVMContext::MD_kcfi_type,
2362 llvm::MDNode::get(
2363 Ctx, MDB.createConstant(CreateKCFITypeId(FD->getType()))));
2364 }
2365
allowKCFIIdentifier(StringRef Name)2366 static bool allowKCFIIdentifier(StringRef Name) {
2367 // KCFI type identifier constants are only necessary for external assembly
2368 // functions, which means it's safe to skip unusual names. Subset of
2369 // MCAsmInfo::isAcceptableChar() and MCAsmInfoXCOFF::isAcceptableChar().
2370 return llvm::all_of(Name, [](const char &C) {
2371 return llvm::isAlnum(C) || C == '_' || C == '.';
2372 });
2373 }
2374
finalizeKCFITypes()2375 void CodeGenModule::finalizeKCFITypes() {
2376 llvm::Module &M = getModule();
2377 for (auto &F : M.functions()) {
2378 // Remove KCFI type metadata from non-address-taken local functions.
2379 bool AddressTaken = F.hasAddressTaken();
2380 if (!AddressTaken && F.hasLocalLinkage())
2381 F.eraseMetadata(llvm::LLVMContext::MD_kcfi_type);
2382
2383 // Generate a constant with the expected KCFI type identifier for all
2384 // address-taken function declarations to support annotating indirectly
2385 // called assembly functions.
2386 if (!AddressTaken || !F.isDeclaration())
2387 continue;
2388
2389 const llvm::ConstantInt *Type;
2390 if (const llvm::MDNode *MD = F.getMetadata(llvm::LLVMContext::MD_kcfi_type))
2391 Type = llvm::mdconst::extract<llvm::ConstantInt>(MD->getOperand(0));
2392 else
2393 continue;
2394
2395 StringRef Name = F.getName();
2396 if (!allowKCFIIdentifier(Name))
2397 continue;
2398
2399 std::string Asm = (".weak __kcfi_typeid_" + Name + "\n.set __kcfi_typeid_" +
2400 Name + ", " + Twine(Type->getZExtValue()) + "\n")
2401 .str();
2402 M.appendModuleInlineAsm(Asm);
2403 }
2404 }
2405
SetFunctionAttributes(GlobalDecl GD,llvm::Function * F,bool IsIncompleteFunction,bool IsThunk)2406 void CodeGenModule::SetFunctionAttributes(GlobalDecl GD, llvm::Function *F,
2407 bool IsIncompleteFunction,
2408 bool IsThunk) {
2409
2410 if (llvm::Intrinsic::ID IID = F->getIntrinsicID()) {
2411 // If this is an intrinsic function, set the function's attributes
2412 // to the intrinsic's attributes.
2413 F->setAttributes(llvm::Intrinsic::getAttributes(getLLVMContext(), IID));
2414 return;
2415 }
2416
2417 const auto *FD = cast<FunctionDecl>(GD.getDecl());
2418
2419 if (!IsIncompleteFunction)
2420 SetLLVMFunctionAttributes(GD, getTypes().arrangeGlobalDeclaration(GD), F,
2421 IsThunk);
2422
2423 // Add the Returned attribute for "this", except for iOS 5 and earlier
2424 // where substantial code, including the libstdc++ dylib, was compiled with
2425 // GCC and does not actually return "this".
2426 if (!IsThunk && getCXXABI().HasThisReturn(GD) &&
2427 !(getTriple().isiOS() && getTriple().isOSVersionLT(6))) {
2428 assert(!F->arg_empty() &&
2429 F->arg_begin()->getType()
2430 ->canLosslesslyBitCastTo(F->getReturnType()) &&
2431 "unexpected this return");
2432 F->addParamAttr(0, llvm::Attribute::Returned);
2433 }
2434
2435 // Only a few attributes are set on declarations; these may later be
2436 // overridden by a definition.
2437
2438 setLinkageForGV(F, FD);
2439 setGVProperties(F, FD);
2440
2441 // Setup target-specific attributes.
2442 if (!IsIncompleteFunction && F->isDeclaration())
2443 getTargetCodeGenInfo().setTargetAttributes(FD, F, *this);
2444
2445 if (const auto *CSA = FD->getAttr<CodeSegAttr>())
2446 F->setSection(CSA->getName());
2447 else if (const auto *SA = FD->getAttr<SectionAttr>())
2448 F->setSection(SA->getName());
2449
2450 if (const auto *EA = FD->getAttr<ErrorAttr>()) {
2451 if (EA->isError())
2452 F->addFnAttr("dontcall-error", EA->getUserDiagnostic());
2453 else if (EA->isWarning())
2454 F->addFnAttr("dontcall-warn", EA->getUserDiagnostic());
2455 }
2456
2457 // If we plan on emitting this inline builtin, we can't treat it as a builtin.
2458 if (FD->isInlineBuiltinDeclaration()) {
2459 const FunctionDecl *FDBody;
2460 bool HasBody = FD->hasBody(FDBody);
2461 (void)HasBody;
2462 assert(HasBody && "Inline builtin declarations should always have an "
2463 "available body!");
2464 if (shouldEmitFunction(FDBody))
2465 F->addFnAttr(llvm::Attribute::NoBuiltin);
2466 }
2467
2468 if (FD->isReplaceableGlobalAllocationFunction()) {
2469 // A replaceable global allocation function does not act like a builtin by
2470 // default, only if it is invoked by a new-expression or delete-expression.
2471 F->addFnAttr(llvm::Attribute::NoBuiltin);
2472 }
2473
2474 if (isa<CXXConstructorDecl>(FD) || isa<CXXDestructorDecl>(FD))
2475 F->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2476 else if (const auto *MD = dyn_cast<CXXMethodDecl>(FD))
2477 if (MD->isVirtual())
2478 F->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2479
2480 // Don't emit entries for function declarations in the cross-DSO mode. This
2481 // is handled with better precision by the receiving DSO. But if jump tables
2482 // are non-canonical then we need type metadata in order to produce the local
2483 // jump table.
2484 if (!CodeGenOpts.SanitizeCfiCrossDso ||
2485 !CodeGenOpts.SanitizeCfiCanonicalJumpTables)
2486 CreateFunctionTypeMetadataForIcall(FD, F);
2487
2488 if (LangOpts.Sanitize.has(SanitizerKind::KCFI))
2489 setKCFIType(FD, F);
2490
2491 if (getLangOpts().OpenMP && FD->hasAttr<OMPDeclareSimdDeclAttr>())
2492 getOpenMPRuntime().emitDeclareSimdFunction(FD, F);
2493
2494 if (CodeGenOpts.InlineMaxStackSize != UINT_MAX)
2495 F->addFnAttr("inline-max-stacksize", llvm::utostr(CodeGenOpts.InlineMaxStackSize));
2496
2497 if (const auto *CB = FD->getAttr<CallbackAttr>()) {
2498 // Annotate the callback behavior as metadata:
2499 // - The callback callee (as argument number).
2500 // - The callback payloads (as argument numbers).
2501 llvm::LLVMContext &Ctx = F->getContext();
2502 llvm::MDBuilder MDB(Ctx);
2503
2504 // The payload indices are all but the first one in the encoding. The first
2505 // identifies the callback callee.
2506 int CalleeIdx = *CB->encoding_begin();
2507 ArrayRef<int> PayloadIndices(CB->encoding_begin() + 1, CB->encoding_end());
2508 F->addMetadata(llvm::LLVMContext::MD_callback,
2509 *llvm::MDNode::get(Ctx, {MDB.createCallbackEncoding(
2510 CalleeIdx, PayloadIndices,
2511 /* VarArgsArePassed */ false)}));
2512 }
2513 }
2514
addUsedGlobal(llvm::GlobalValue * GV)2515 void CodeGenModule::addUsedGlobal(llvm::GlobalValue *GV) {
2516 assert((isa<llvm::Function>(GV) || !GV->isDeclaration()) &&
2517 "Only globals with definition can force usage.");
2518 LLVMUsed.emplace_back(GV);
2519 }
2520
addCompilerUsedGlobal(llvm::GlobalValue * GV)2521 void CodeGenModule::addCompilerUsedGlobal(llvm::GlobalValue *GV) {
2522 assert(!GV->isDeclaration() &&
2523 "Only globals with definition can force usage.");
2524 LLVMCompilerUsed.emplace_back(GV);
2525 }
2526
addUsedOrCompilerUsedGlobal(llvm::GlobalValue * GV)2527 void CodeGenModule::addUsedOrCompilerUsedGlobal(llvm::GlobalValue *GV) {
2528 assert((isa<llvm::Function>(GV) || !GV->isDeclaration()) &&
2529 "Only globals with definition can force usage.");
2530 if (getTriple().isOSBinFormatELF())
2531 LLVMCompilerUsed.emplace_back(GV);
2532 else
2533 LLVMUsed.emplace_back(GV);
2534 }
2535
emitUsed(CodeGenModule & CGM,StringRef Name,std::vector<llvm::WeakTrackingVH> & List)2536 static void emitUsed(CodeGenModule &CGM, StringRef Name,
2537 std::vector<llvm::WeakTrackingVH> &List) {
2538 // Don't create llvm.used if there is no need.
2539 if (List.empty())
2540 return;
2541
2542 // Convert List to what ConstantArray needs.
2543 SmallVector<llvm::Constant*, 8> UsedArray;
2544 UsedArray.resize(List.size());
2545 for (unsigned i = 0, e = List.size(); i != e; ++i) {
2546 UsedArray[i] =
2547 llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(
2548 cast<llvm::Constant>(&*List[i]), CGM.Int8PtrTy);
2549 }
2550
2551 if (UsedArray.empty())
2552 return;
2553 llvm::ArrayType *ATy = llvm::ArrayType::get(CGM.Int8PtrTy, UsedArray.size());
2554
2555 auto *GV = new llvm::GlobalVariable(
2556 CGM.getModule(), ATy, false, llvm::GlobalValue::AppendingLinkage,
2557 llvm::ConstantArray::get(ATy, UsedArray), Name);
2558
2559 GV->setSection("llvm.metadata");
2560 }
2561
emitLLVMUsed()2562 void CodeGenModule::emitLLVMUsed() {
2563 emitUsed(*this, "llvm.used", LLVMUsed);
2564 emitUsed(*this, "llvm.compiler.used", LLVMCompilerUsed);
2565 }
2566
AppendLinkerOptions(StringRef Opts)2567 void CodeGenModule::AppendLinkerOptions(StringRef Opts) {
2568 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opts);
2569 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts));
2570 }
2571
AddDetectMismatch(StringRef Name,StringRef Value)2572 void CodeGenModule::AddDetectMismatch(StringRef Name, StringRef Value) {
2573 llvm::SmallString<32> Opt;
2574 getTargetCodeGenInfo().getDetectMismatchOption(Name, Value, Opt);
2575 if (Opt.empty())
2576 return;
2577 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opt);
2578 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts));
2579 }
2580
AddDependentLib(StringRef Lib)2581 void CodeGenModule::AddDependentLib(StringRef Lib) {
2582 auto &C = getLLVMContext();
2583 if (getTarget().getTriple().isOSBinFormatELF()) {
2584 ELFDependentLibraries.push_back(
2585 llvm::MDNode::get(C, llvm::MDString::get(C, Lib)));
2586 return;
2587 }
2588
2589 llvm::SmallString<24> Opt;
2590 getTargetCodeGenInfo().getDependentLibraryOption(Lib, Opt);
2591 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opt);
2592 LinkerOptionsMetadata.push_back(llvm::MDNode::get(C, MDOpts));
2593 }
2594
2595 /// Add link options implied by the given module, including modules
2596 /// it depends on, using a postorder walk.
addLinkOptionsPostorder(CodeGenModule & CGM,Module * Mod,SmallVectorImpl<llvm::MDNode * > & Metadata,llvm::SmallPtrSet<Module *,16> & Visited)2597 static void addLinkOptionsPostorder(CodeGenModule &CGM, Module *Mod,
2598 SmallVectorImpl<llvm::MDNode *> &Metadata,
2599 llvm::SmallPtrSet<Module *, 16> &Visited) {
2600 // Import this module's parent.
2601 if (Mod->Parent && Visited.insert(Mod->Parent).second) {
2602 addLinkOptionsPostorder(CGM, Mod->Parent, Metadata, Visited);
2603 }
2604
2605 // Import this module's dependencies.
2606 for (Module *Import : llvm::reverse(Mod->Imports)) {
2607 if (Visited.insert(Import).second)
2608 addLinkOptionsPostorder(CGM, Import, Metadata, Visited);
2609 }
2610
2611 // Add linker options to link against the libraries/frameworks
2612 // described by this module.
2613 llvm::LLVMContext &Context = CGM.getLLVMContext();
2614 bool IsELF = CGM.getTarget().getTriple().isOSBinFormatELF();
2615
2616 // For modules that use export_as for linking, use that module
2617 // name instead.
2618 if (Mod->UseExportAsModuleLinkName)
2619 return;
2620
2621 for (const Module::LinkLibrary &LL : llvm::reverse(Mod->LinkLibraries)) {
2622 // Link against a framework. Frameworks are currently Darwin only, so we
2623 // don't to ask TargetCodeGenInfo for the spelling of the linker option.
2624 if (LL.IsFramework) {
2625 llvm::Metadata *Args[2] = {llvm::MDString::get(Context, "-framework"),
2626 llvm::MDString::get(Context, LL.Library)};
2627
2628 Metadata.push_back(llvm::MDNode::get(Context, Args));
2629 continue;
2630 }
2631
2632 // Link against a library.
2633 if (IsELF) {
2634 llvm::Metadata *Args[2] = {
2635 llvm::MDString::get(Context, "lib"),
2636 llvm::MDString::get(Context, LL.Library),
2637 };
2638 Metadata.push_back(llvm::MDNode::get(Context, Args));
2639 } else {
2640 llvm::SmallString<24> Opt;
2641 CGM.getTargetCodeGenInfo().getDependentLibraryOption(LL.Library, Opt);
2642 auto *OptString = llvm::MDString::get(Context, Opt);
2643 Metadata.push_back(llvm::MDNode::get(Context, OptString));
2644 }
2645 }
2646 }
2647
EmitModuleInitializers(clang::Module * Primary)2648 void CodeGenModule::EmitModuleInitializers(clang::Module *Primary) {
2649 // Emit the initializers in the order that sub-modules appear in the
2650 // source, first Global Module Fragments, if present.
2651 if (auto GMF = Primary->getGlobalModuleFragment()) {
2652 for (Decl *D : getContext().getModuleInitializers(GMF)) {
2653 if (isa<ImportDecl>(D))
2654 continue;
2655 assert(isa<VarDecl>(D) && "GMF initializer decl is not a var?");
2656 EmitTopLevelDecl(D);
2657 }
2658 }
2659 // Second any associated with the module, itself.
2660 for (Decl *D : getContext().getModuleInitializers(Primary)) {
2661 // Skip import decls, the inits for those are called explicitly.
2662 if (isa<ImportDecl>(D))
2663 continue;
2664 EmitTopLevelDecl(D);
2665 }
2666 // Third any associated with the Privat eMOdule Fragment, if present.
2667 if (auto PMF = Primary->getPrivateModuleFragment()) {
2668 for (Decl *D : getContext().getModuleInitializers(PMF)) {
2669 assert(isa<VarDecl>(D) && "PMF initializer decl is not a var?");
2670 EmitTopLevelDecl(D);
2671 }
2672 }
2673 }
2674
EmitModuleLinkOptions()2675 void CodeGenModule::EmitModuleLinkOptions() {
2676 // Collect the set of all of the modules we want to visit to emit link
2677 // options, which is essentially the imported modules and all of their
2678 // non-explicit child modules.
2679 llvm::SetVector<clang::Module *> LinkModules;
2680 llvm::SmallPtrSet<clang::Module *, 16> Visited;
2681 SmallVector<clang::Module *, 16> Stack;
2682
2683 // Seed the stack with imported modules.
2684 for (Module *M : ImportedModules) {
2685 // Do not add any link flags when an implementation TU of a module imports
2686 // a header of that same module.
2687 if (M->getTopLevelModuleName() == getLangOpts().CurrentModule &&
2688 !getLangOpts().isCompilingModule())
2689 continue;
2690 if (Visited.insert(M).second)
2691 Stack.push_back(M);
2692 }
2693
2694 // Find all of the modules to import, making a little effort to prune
2695 // non-leaf modules.
2696 while (!Stack.empty()) {
2697 clang::Module *Mod = Stack.pop_back_val();
2698
2699 bool AnyChildren = false;
2700
2701 // Visit the submodules of this module.
2702 for (const auto &SM : Mod->submodules()) {
2703 // Skip explicit children; they need to be explicitly imported to be
2704 // linked against.
2705 if (SM->IsExplicit)
2706 continue;
2707
2708 if (Visited.insert(SM).second) {
2709 Stack.push_back(SM);
2710 AnyChildren = true;
2711 }
2712 }
2713
2714 // We didn't find any children, so add this module to the list of
2715 // modules to link against.
2716 if (!AnyChildren) {
2717 LinkModules.insert(Mod);
2718 }
2719 }
2720
2721 // Add link options for all of the imported modules in reverse topological
2722 // order. We don't do anything to try to order import link flags with respect
2723 // to linker options inserted by things like #pragma comment().
2724 SmallVector<llvm::MDNode *, 16> MetadataArgs;
2725 Visited.clear();
2726 for (Module *M : LinkModules)
2727 if (Visited.insert(M).second)
2728 addLinkOptionsPostorder(*this, M, MetadataArgs, Visited);
2729 std::reverse(MetadataArgs.begin(), MetadataArgs.end());
2730 LinkerOptionsMetadata.append(MetadataArgs.begin(), MetadataArgs.end());
2731
2732 // Add the linker options metadata flag.
2733 auto *NMD = getModule().getOrInsertNamedMetadata("llvm.linker.options");
2734 for (auto *MD : LinkerOptionsMetadata)
2735 NMD->addOperand(MD);
2736 }
2737
EmitDeferred()2738 void CodeGenModule::EmitDeferred() {
2739 // Emit deferred declare target declarations.
2740 if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd)
2741 getOpenMPRuntime().emitDeferredTargetDecls();
2742
2743 // Emit code for any potentially referenced deferred decls. Since a
2744 // previously unused static decl may become used during the generation of code
2745 // for a static function, iterate until no changes are made.
2746
2747 if (!DeferredVTables.empty()) {
2748 EmitDeferredVTables();
2749
2750 // Emitting a vtable doesn't directly cause more vtables to
2751 // become deferred, although it can cause functions to be
2752 // emitted that then need those vtables.
2753 assert(DeferredVTables.empty());
2754 }
2755
2756 // Emit CUDA/HIP static device variables referenced by host code only.
2757 // Note we should not clear CUDADeviceVarODRUsedByHost since it is still
2758 // needed for further handling.
2759 if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice)
2760 llvm::append_range(DeferredDeclsToEmit,
2761 getContext().CUDADeviceVarODRUsedByHost);
2762
2763 // Stop if we're out of both deferred vtables and deferred declarations.
2764 if (DeferredDeclsToEmit.empty())
2765 return;
2766
2767 // Grab the list of decls to emit. If EmitGlobalDefinition schedules more
2768 // work, it will not interfere with this.
2769 std::vector<GlobalDecl> CurDeclsToEmit;
2770 CurDeclsToEmit.swap(DeferredDeclsToEmit);
2771
2772 for (GlobalDecl &D : CurDeclsToEmit) {
2773 // We should call GetAddrOfGlobal with IsForDefinition set to true in order
2774 // to get GlobalValue with exactly the type we need, not something that
2775 // might had been created for another decl with the same mangled name but
2776 // different type.
2777 llvm::GlobalValue *GV = dyn_cast<llvm::GlobalValue>(
2778 GetAddrOfGlobal(D, ForDefinition));
2779
2780 // In case of different address spaces, we may still get a cast, even with
2781 // IsForDefinition equal to true. Query mangled names table to get
2782 // GlobalValue.
2783 if (!GV)
2784 GV = GetGlobalValue(getMangledName(D));
2785
2786 // Make sure GetGlobalValue returned non-null.
2787 assert(GV);
2788
2789 // Check to see if we've already emitted this. This is necessary
2790 // for a couple of reasons: first, decls can end up in the
2791 // deferred-decls queue multiple times, and second, decls can end
2792 // up with definitions in unusual ways (e.g. by an extern inline
2793 // function acquiring a strong function redefinition). Just
2794 // ignore these cases.
2795 if (!GV->isDeclaration())
2796 continue;
2797
2798 // If this is OpenMP, check if it is legal to emit this global normally.
2799 if (LangOpts.OpenMP && OpenMPRuntime && OpenMPRuntime->emitTargetGlobal(D))
2800 continue;
2801
2802 // Otherwise, emit the definition and move on to the next one.
2803 EmitGlobalDefinition(D, GV);
2804
2805 // If we found out that we need to emit more decls, do that recursively.
2806 // This has the advantage that the decls are emitted in a DFS and related
2807 // ones are close together, which is convenient for testing.
2808 if (!DeferredVTables.empty() || !DeferredDeclsToEmit.empty()) {
2809 EmitDeferred();
2810 assert(DeferredVTables.empty() && DeferredDeclsToEmit.empty());
2811 }
2812 }
2813 }
2814
EmitVTablesOpportunistically()2815 void CodeGenModule::EmitVTablesOpportunistically() {
2816 // Try to emit external vtables as available_externally if they have emitted
2817 // all inlined virtual functions. It runs after EmitDeferred() and therefore
2818 // is not allowed to create new references to things that need to be emitted
2819 // lazily. Note that it also uses fact that we eagerly emitting RTTI.
2820
2821 assert((OpportunisticVTables.empty() || shouldOpportunisticallyEmitVTables())
2822 && "Only emit opportunistic vtables with optimizations");
2823
2824 for (const CXXRecordDecl *RD : OpportunisticVTables) {
2825 assert(getVTables().isVTableExternal(RD) &&
2826 "This queue should only contain external vtables");
2827 if (getCXXABI().canSpeculativelyEmitVTable(RD))
2828 VTables.GenerateClassData(RD);
2829 }
2830 OpportunisticVTables.clear();
2831 }
2832
EmitGlobalAnnotations()2833 void CodeGenModule::EmitGlobalAnnotations() {
2834 if (Annotations.empty())
2835 return;
2836
2837 // Create a new global variable for the ConstantStruct in the Module.
2838 llvm::Constant *Array = llvm::ConstantArray::get(llvm::ArrayType::get(
2839 Annotations[0]->getType(), Annotations.size()), Annotations);
2840 auto *gv = new llvm::GlobalVariable(getModule(), Array->getType(), false,
2841 llvm::GlobalValue::AppendingLinkage,
2842 Array, "llvm.global.annotations");
2843 gv->setSection(AnnotationSection);
2844 }
2845
EmitAnnotationString(StringRef Str)2846 llvm::Constant *CodeGenModule::EmitAnnotationString(StringRef Str) {
2847 llvm::Constant *&AStr = AnnotationStrings[Str];
2848 if (AStr)
2849 return AStr;
2850
2851 // Not found yet, create a new global.
2852 llvm::Constant *s = llvm::ConstantDataArray::getString(getLLVMContext(), Str);
2853 auto *gv = new llvm::GlobalVariable(
2854 getModule(), s->getType(), true, llvm::GlobalValue::PrivateLinkage, s,
2855 ".str", nullptr, llvm::GlobalValue::NotThreadLocal,
2856 ConstGlobalsPtrTy->getAddressSpace());
2857 gv->setSection(AnnotationSection);
2858 gv->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2859 AStr = gv;
2860 return gv;
2861 }
2862
EmitAnnotationUnit(SourceLocation Loc)2863 llvm::Constant *CodeGenModule::EmitAnnotationUnit(SourceLocation Loc) {
2864 SourceManager &SM = getContext().getSourceManager();
2865 PresumedLoc PLoc = SM.getPresumedLoc(Loc);
2866 if (PLoc.isValid())
2867 return EmitAnnotationString(PLoc.getFilename());
2868 return EmitAnnotationString(SM.getBufferName(Loc));
2869 }
2870
EmitAnnotationLineNo(SourceLocation L)2871 llvm::Constant *CodeGenModule::EmitAnnotationLineNo(SourceLocation L) {
2872 SourceManager &SM = getContext().getSourceManager();
2873 PresumedLoc PLoc = SM.getPresumedLoc(L);
2874 unsigned LineNo = PLoc.isValid() ? PLoc.getLine() :
2875 SM.getExpansionLineNumber(L);
2876 return llvm::ConstantInt::get(Int32Ty, LineNo);
2877 }
2878
EmitAnnotationArgs(const AnnotateAttr * Attr)2879 llvm::Constant *CodeGenModule::EmitAnnotationArgs(const AnnotateAttr *Attr) {
2880 ArrayRef<Expr *> Exprs = {Attr->args_begin(), Attr->args_size()};
2881 if (Exprs.empty())
2882 return llvm::ConstantPointerNull::get(ConstGlobalsPtrTy);
2883
2884 llvm::FoldingSetNodeID ID;
2885 for (Expr *E : Exprs) {
2886 ID.Add(cast<clang::ConstantExpr>(E)->getAPValueResult());
2887 }
2888 llvm::Constant *&Lookup = AnnotationArgs[ID.ComputeHash()];
2889 if (Lookup)
2890 return Lookup;
2891
2892 llvm::SmallVector<llvm::Constant *, 4> LLVMArgs;
2893 LLVMArgs.reserve(Exprs.size());
2894 ConstantEmitter ConstEmiter(*this);
2895 llvm::transform(Exprs, std::back_inserter(LLVMArgs), [&](const Expr *E) {
2896 const auto *CE = cast<clang::ConstantExpr>(E);
2897 return ConstEmiter.emitAbstract(CE->getBeginLoc(), CE->getAPValueResult(),
2898 CE->getType());
2899 });
2900 auto *Struct = llvm::ConstantStruct::getAnon(LLVMArgs);
2901 auto *GV = new llvm::GlobalVariable(getModule(), Struct->getType(), true,
2902 llvm::GlobalValue::PrivateLinkage, Struct,
2903 ".args");
2904 GV->setSection(AnnotationSection);
2905 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2906 auto *Bitcasted = llvm::ConstantExpr::getBitCast(GV, GlobalsInt8PtrTy);
2907
2908 Lookup = Bitcasted;
2909 return Bitcasted;
2910 }
2911
EmitAnnotateAttr(llvm::GlobalValue * GV,const AnnotateAttr * AA,SourceLocation L)2912 llvm::Constant *CodeGenModule::EmitAnnotateAttr(llvm::GlobalValue *GV,
2913 const AnnotateAttr *AA,
2914 SourceLocation L) {
2915 // Get the globals for file name, annotation, and the line number.
2916 llvm::Constant *AnnoGV = EmitAnnotationString(AA->getAnnotation()),
2917 *UnitGV = EmitAnnotationUnit(L),
2918 *LineNoCst = EmitAnnotationLineNo(L),
2919 *Args = EmitAnnotationArgs(AA);
2920
2921 llvm::Constant *GVInGlobalsAS = GV;
2922 if (GV->getAddressSpace() !=
2923 getDataLayout().getDefaultGlobalsAddressSpace()) {
2924 GVInGlobalsAS = llvm::ConstantExpr::getAddrSpaceCast(
2925 GV, GV->getValueType()->getPointerTo(
2926 getDataLayout().getDefaultGlobalsAddressSpace()));
2927 }
2928
2929 // Create the ConstantStruct for the global annotation.
2930 llvm::Constant *Fields[] = {
2931 llvm::ConstantExpr::getBitCast(GVInGlobalsAS, GlobalsInt8PtrTy),
2932 llvm::ConstantExpr::getBitCast(AnnoGV, ConstGlobalsPtrTy),
2933 llvm::ConstantExpr::getBitCast(UnitGV, ConstGlobalsPtrTy),
2934 LineNoCst,
2935 Args,
2936 };
2937 return llvm::ConstantStruct::getAnon(Fields);
2938 }
2939
AddGlobalAnnotations(const ValueDecl * D,llvm::GlobalValue * GV)2940 void CodeGenModule::AddGlobalAnnotations(const ValueDecl *D,
2941 llvm::GlobalValue *GV) {
2942 assert(D->hasAttr<AnnotateAttr>() && "no annotate attribute");
2943 // Get the struct elements for these annotations.
2944 for (const auto *I : D->specific_attrs<AnnotateAttr>())
2945 Annotations.push_back(EmitAnnotateAttr(GV, I, D->getLocation()));
2946 }
2947
isInNoSanitizeList(SanitizerMask Kind,llvm::Function * Fn,SourceLocation Loc) const2948 bool CodeGenModule::isInNoSanitizeList(SanitizerMask Kind, llvm::Function *Fn,
2949 SourceLocation Loc) const {
2950 const auto &NoSanitizeL = getContext().getNoSanitizeList();
2951 // NoSanitize by function name.
2952 if (NoSanitizeL.containsFunction(Kind, Fn->getName()))
2953 return true;
2954 // NoSanitize by location. Check "mainfile" prefix.
2955 auto &SM = Context.getSourceManager();
2956 const FileEntry &MainFile = *SM.getFileEntryForID(SM.getMainFileID());
2957 if (NoSanitizeL.containsMainFile(Kind, MainFile.getName()))
2958 return true;
2959
2960 // Check "src" prefix.
2961 if (Loc.isValid())
2962 return NoSanitizeL.containsLocation(Kind, Loc);
2963 // If location is unknown, this may be a compiler-generated function. Assume
2964 // it's located in the main file.
2965 return NoSanitizeL.containsFile(Kind, MainFile.getName());
2966 }
2967
isInNoSanitizeList(SanitizerMask Kind,llvm::GlobalVariable * GV,SourceLocation Loc,QualType Ty,StringRef Category) const2968 bool CodeGenModule::isInNoSanitizeList(SanitizerMask Kind,
2969 llvm::GlobalVariable *GV,
2970 SourceLocation Loc, QualType Ty,
2971 StringRef Category) const {
2972 const auto &NoSanitizeL = getContext().getNoSanitizeList();
2973 if (NoSanitizeL.containsGlobal(Kind, GV->getName(), Category))
2974 return true;
2975 auto &SM = Context.getSourceManager();
2976 if (NoSanitizeL.containsMainFile(
2977 Kind, SM.getFileEntryForID(SM.getMainFileID())->getName(), Category))
2978 return true;
2979 if (NoSanitizeL.containsLocation(Kind, Loc, Category))
2980 return true;
2981
2982 // Check global type.
2983 if (!Ty.isNull()) {
2984 // Drill down the array types: if global variable of a fixed type is
2985 // not sanitized, we also don't instrument arrays of them.
2986 while (auto AT = dyn_cast<ArrayType>(Ty.getTypePtr()))
2987 Ty = AT->getElementType();
2988 Ty = Ty.getCanonicalType().getUnqualifiedType();
2989 // Only record types (classes, structs etc.) are ignored.
2990 if (Ty->isRecordType()) {
2991 std::string TypeStr = Ty.getAsString(getContext().getPrintingPolicy());
2992 if (NoSanitizeL.containsType(Kind, TypeStr, Category))
2993 return true;
2994 }
2995 }
2996 return false;
2997 }
2998
imbueXRayAttrs(llvm::Function * Fn,SourceLocation Loc,StringRef Category) const2999 bool CodeGenModule::imbueXRayAttrs(llvm::Function *Fn, SourceLocation Loc,
3000 StringRef Category) const {
3001 const auto &XRayFilter = getContext().getXRayFilter();
3002 using ImbueAttr = XRayFunctionFilter::ImbueAttribute;
3003 auto Attr = ImbueAttr::NONE;
3004 if (Loc.isValid())
3005 Attr = XRayFilter.shouldImbueLocation(Loc, Category);
3006 if (Attr == ImbueAttr::NONE)
3007 Attr = XRayFilter.shouldImbueFunction(Fn->getName());
3008 switch (Attr) {
3009 case ImbueAttr::NONE:
3010 return false;
3011 case ImbueAttr::ALWAYS:
3012 Fn->addFnAttr("function-instrument", "xray-always");
3013 break;
3014 case ImbueAttr::ALWAYS_ARG1:
3015 Fn->addFnAttr("function-instrument", "xray-always");
3016 Fn->addFnAttr("xray-log-args", "1");
3017 break;
3018 case ImbueAttr::NEVER:
3019 Fn->addFnAttr("function-instrument", "xray-never");
3020 break;
3021 }
3022 return true;
3023 }
3024
3025 ProfileList::ExclusionType
isFunctionBlockedByProfileList(llvm::Function * Fn,SourceLocation Loc) const3026 CodeGenModule::isFunctionBlockedByProfileList(llvm::Function *Fn,
3027 SourceLocation Loc) const {
3028 const auto &ProfileList = getContext().getProfileList();
3029 // If the profile list is empty, then instrument everything.
3030 if (ProfileList.isEmpty())
3031 return ProfileList::Allow;
3032 CodeGenOptions::ProfileInstrKind Kind = getCodeGenOpts().getProfileInstr();
3033 // First, check the function name.
3034 if (auto V = ProfileList.isFunctionExcluded(Fn->getName(), Kind))
3035 return *V;
3036 // Next, check the source location.
3037 if (Loc.isValid())
3038 if (auto V = ProfileList.isLocationExcluded(Loc, Kind))
3039 return *V;
3040 // If location is unknown, this may be a compiler-generated function. Assume
3041 // it's located in the main file.
3042 auto &SM = Context.getSourceManager();
3043 if (const auto *MainFile = SM.getFileEntryForID(SM.getMainFileID()))
3044 if (auto V = ProfileList.isFileExcluded(MainFile->getName(), Kind))
3045 return *V;
3046 return ProfileList.getDefault(Kind);
3047 }
3048
3049 ProfileList::ExclusionType
isFunctionBlockedFromProfileInstr(llvm::Function * Fn,SourceLocation Loc) const3050 CodeGenModule::isFunctionBlockedFromProfileInstr(llvm::Function *Fn,
3051 SourceLocation Loc) const {
3052 auto V = isFunctionBlockedByProfileList(Fn, Loc);
3053 if (V != ProfileList::Allow)
3054 return V;
3055
3056 auto NumGroups = getCodeGenOpts().ProfileTotalFunctionGroups;
3057 if (NumGroups > 1) {
3058 auto Group = llvm::crc32(arrayRefFromStringRef(Fn->getName())) % NumGroups;
3059 if (Group != getCodeGenOpts().ProfileSelectedFunctionGroup)
3060 return ProfileList::Skip;
3061 }
3062 return ProfileList::Allow;
3063 }
3064
MustBeEmitted(const ValueDecl * Global)3065 bool CodeGenModule::MustBeEmitted(const ValueDecl *Global) {
3066 // Never defer when EmitAllDecls is specified.
3067 if (LangOpts.EmitAllDecls)
3068 return true;
3069
3070 if (CodeGenOpts.KeepStaticConsts) {
3071 const auto *VD = dyn_cast<VarDecl>(Global);
3072 if (VD && VD->getType().isConstQualified() &&
3073 VD->getStorageDuration() == SD_Static)
3074 return true;
3075 }
3076
3077 return getContext().DeclMustBeEmitted(Global);
3078 }
3079
MayBeEmittedEagerly(const ValueDecl * Global)3080 bool CodeGenModule::MayBeEmittedEagerly(const ValueDecl *Global) {
3081 // In OpenMP 5.0 variables and function may be marked as
3082 // device_type(host/nohost) and we should not emit them eagerly unless we sure
3083 // that they must be emitted on the host/device. To be sure we need to have
3084 // seen a declare target with an explicit mentioning of the function, we know
3085 // we have if the level of the declare target attribute is -1. Note that we
3086 // check somewhere else if we should emit this at all.
3087 if (LangOpts.OpenMP >= 50 && !LangOpts.OpenMPSimd) {
3088 std::optional<OMPDeclareTargetDeclAttr *> ActiveAttr =
3089 OMPDeclareTargetDeclAttr::getActiveAttr(Global);
3090 if (!ActiveAttr || (*ActiveAttr)->getLevel() != (unsigned)-1)
3091 return false;
3092 }
3093
3094 if (const auto *FD = dyn_cast<FunctionDecl>(Global)) {
3095 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
3096 // Implicit template instantiations may change linkage if they are later
3097 // explicitly instantiated, so they should not be emitted eagerly.
3098 return false;
3099 }
3100 if (const auto *VD = dyn_cast<VarDecl>(Global)) {
3101 if (Context.getInlineVariableDefinitionKind(VD) ==
3102 ASTContext::InlineVariableDefinitionKind::WeakUnknown)
3103 // A definition of an inline constexpr static data member may change
3104 // linkage later if it's redeclared outside the class.
3105 return false;
3106 if (CXX20ModuleInits && VD->getOwningModule() &&
3107 !VD->getOwningModule()->isModuleMapModule()) {
3108 // For CXX20, module-owned initializers need to be deferred, since it is
3109 // not known at this point if they will be run for the current module or
3110 // as part of the initializer for an imported one.
3111 return false;
3112 }
3113 }
3114 // If OpenMP is enabled and threadprivates must be generated like TLS, delay
3115 // codegen for global variables, because they may be marked as threadprivate.
3116 if (LangOpts.OpenMP && LangOpts.OpenMPUseTLS &&
3117 getContext().getTargetInfo().isTLSSupported() && isa<VarDecl>(Global) &&
3118 !isTypeConstant(Global->getType(), false) &&
3119 !OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(Global))
3120 return false;
3121
3122 return true;
3123 }
3124
GetAddrOfMSGuidDecl(const MSGuidDecl * GD)3125 ConstantAddress CodeGenModule::GetAddrOfMSGuidDecl(const MSGuidDecl *GD) {
3126 StringRef Name = getMangledName(GD);
3127
3128 // The UUID descriptor should be pointer aligned.
3129 CharUnits Alignment = CharUnits::fromQuantity(PointerAlignInBytes);
3130
3131 // Look for an existing global.
3132 if (llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name))
3133 return ConstantAddress(GV, GV->getValueType(), Alignment);
3134
3135 ConstantEmitter Emitter(*this);
3136 llvm::Constant *Init;
3137
3138 APValue &V = GD->getAsAPValue();
3139 if (!V.isAbsent()) {
3140 // If possible, emit the APValue version of the initializer. In particular,
3141 // this gets the type of the constant right.
3142 Init = Emitter.emitForInitializer(
3143 GD->getAsAPValue(), GD->getType().getAddressSpace(), GD->getType());
3144 } else {
3145 // As a fallback, directly construct the constant.
3146 // FIXME: This may get padding wrong under esoteric struct layout rules.
3147 // MSVC appears to create a complete type 'struct __s_GUID' that it
3148 // presumably uses to represent these constants.
3149 MSGuidDecl::Parts Parts = GD->getParts();
3150 llvm::Constant *Fields[4] = {
3151 llvm::ConstantInt::get(Int32Ty, Parts.Part1),
3152 llvm::ConstantInt::get(Int16Ty, Parts.Part2),
3153 llvm::ConstantInt::get(Int16Ty, Parts.Part3),
3154 llvm::ConstantDataArray::getRaw(
3155 StringRef(reinterpret_cast<char *>(Parts.Part4And5), 8), 8,
3156 Int8Ty)};
3157 Init = llvm::ConstantStruct::getAnon(Fields);
3158 }
3159
3160 auto *GV = new llvm::GlobalVariable(
3161 getModule(), Init->getType(),
3162 /*isConstant=*/true, llvm::GlobalValue::LinkOnceODRLinkage, Init, Name);
3163 if (supportsCOMDAT())
3164 GV->setComdat(TheModule.getOrInsertComdat(GV->getName()));
3165 setDSOLocal(GV);
3166
3167 if (!V.isAbsent()) {
3168 Emitter.finalize(GV);
3169 return ConstantAddress(GV, GV->getValueType(), Alignment);
3170 }
3171
3172 llvm::Type *Ty = getTypes().ConvertTypeForMem(GD->getType());
3173 llvm::Constant *Addr = llvm::ConstantExpr::getBitCast(
3174 GV, Ty->getPointerTo(GV->getAddressSpace()));
3175 return ConstantAddress(Addr, Ty, Alignment);
3176 }
3177
GetAddrOfUnnamedGlobalConstantDecl(const UnnamedGlobalConstantDecl * GCD)3178 ConstantAddress CodeGenModule::GetAddrOfUnnamedGlobalConstantDecl(
3179 const UnnamedGlobalConstantDecl *GCD) {
3180 CharUnits Alignment = getContext().getTypeAlignInChars(GCD->getType());
3181
3182 llvm::GlobalVariable **Entry = nullptr;
3183 Entry = &UnnamedGlobalConstantDeclMap[GCD];
3184 if (*Entry)
3185 return ConstantAddress(*Entry, (*Entry)->getValueType(), Alignment);
3186
3187 ConstantEmitter Emitter(*this);
3188 llvm::Constant *Init;
3189
3190 const APValue &V = GCD->getValue();
3191
3192 assert(!V.isAbsent());
3193 Init = Emitter.emitForInitializer(V, GCD->getType().getAddressSpace(),
3194 GCD->getType());
3195
3196 auto *GV = new llvm::GlobalVariable(getModule(), Init->getType(),
3197 /*isConstant=*/true,
3198 llvm::GlobalValue::PrivateLinkage, Init,
3199 ".constant");
3200 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
3201 GV->setAlignment(Alignment.getAsAlign());
3202
3203 Emitter.finalize(GV);
3204
3205 *Entry = GV;
3206 return ConstantAddress(GV, GV->getValueType(), Alignment);
3207 }
3208
GetAddrOfTemplateParamObject(const TemplateParamObjectDecl * TPO)3209 ConstantAddress CodeGenModule::GetAddrOfTemplateParamObject(
3210 const TemplateParamObjectDecl *TPO) {
3211 StringRef Name = getMangledName(TPO);
3212 CharUnits Alignment = getNaturalTypeAlignment(TPO->getType());
3213
3214 if (llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name))
3215 return ConstantAddress(GV, GV->getValueType(), Alignment);
3216
3217 ConstantEmitter Emitter(*this);
3218 llvm::Constant *Init = Emitter.emitForInitializer(
3219 TPO->getValue(), TPO->getType().getAddressSpace(), TPO->getType());
3220
3221 if (!Init) {
3222 ErrorUnsupported(TPO, "template parameter object");
3223 return ConstantAddress::invalid();
3224 }
3225
3226 auto *GV = new llvm::GlobalVariable(
3227 getModule(), Init->getType(),
3228 /*isConstant=*/true, llvm::GlobalValue::LinkOnceODRLinkage, Init, Name);
3229 if (supportsCOMDAT())
3230 GV->setComdat(TheModule.getOrInsertComdat(GV->getName()));
3231 Emitter.finalize(GV);
3232
3233 return ConstantAddress(GV, GV->getValueType(), Alignment);
3234 }
3235
GetWeakRefReference(const ValueDecl * VD)3236 ConstantAddress CodeGenModule::GetWeakRefReference(const ValueDecl *VD) {
3237 const AliasAttr *AA = VD->getAttr<AliasAttr>();
3238 assert(AA && "No alias?");
3239
3240 CharUnits Alignment = getContext().getDeclAlign(VD);
3241 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(VD->getType());
3242
3243 // See if there is already something with the target's name in the module.
3244 llvm::GlobalValue *Entry = GetGlobalValue(AA->getAliasee());
3245 if (Entry) {
3246 unsigned AS = getTypes().getTargetAddressSpace(VD->getType());
3247 auto Ptr = llvm::ConstantExpr::getBitCast(Entry, DeclTy->getPointerTo(AS));
3248 return ConstantAddress(Ptr, DeclTy, Alignment);
3249 }
3250
3251 llvm::Constant *Aliasee;
3252 if (isa<llvm::FunctionType>(DeclTy))
3253 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy,
3254 GlobalDecl(cast<FunctionDecl>(VD)),
3255 /*ForVTable=*/false);
3256 else
3257 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), DeclTy, LangAS::Default,
3258 nullptr);
3259
3260 auto *F = cast<llvm::GlobalValue>(Aliasee);
3261 F->setLinkage(llvm::Function::ExternalWeakLinkage);
3262 WeakRefReferences.insert(F);
3263
3264 return ConstantAddress(Aliasee, DeclTy, Alignment);
3265 }
3266
EmitGlobal(GlobalDecl GD)3267 void CodeGenModule::EmitGlobal(GlobalDecl GD) {
3268 const auto *Global = cast<ValueDecl>(GD.getDecl());
3269
3270 // Weak references don't produce any output by themselves.
3271 if (Global->hasAttr<WeakRefAttr>())
3272 return;
3273
3274 // If this is an alias definition (which otherwise looks like a declaration)
3275 // emit it now.
3276 if (Global->hasAttr<AliasAttr>())
3277 return EmitAliasDefinition(GD);
3278
3279 // IFunc like an alias whose value is resolved at runtime by calling resolver.
3280 if (Global->hasAttr<IFuncAttr>())
3281 return emitIFuncDefinition(GD);
3282
3283 // If this is a cpu_dispatch multiversion function, emit the resolver.
3284 if (Global->hasAttr<CPUDispatchAttr>())
3285 return emitCPUDispatchDefinition(GD);
3286
3287 // If this is CUDA, be selective about which declarations we emit.
3288 if (LangOpts.CUDA) {
3289 if (LangOpts.CUDAIsDevice) {
3290 if (!Global->hasAttr<CUDADeviceAttr>() &&
3291 !Global->hasAttr<CUDAGlobalAttr>() &&
3292 !Global->hasAttr<CUDAConstantAttr>() &&
3293 !Global->hasAttr<CUDASharedAttr>() &&
3294 !Global->getType()->isCUDADeviceBuiltinSurfaceType() &&
3295 !Global->getType()->isCUDADeviceBuiltinTextureType())
3296 return;
3297 } else {
3298 // We need to emit host-side 'shadows' for all global
3299 // device-side variables because the CUDA runtime needs their
3300 // size and host-side address in order to provide access to
3301 // their device-side incarnations.
3302
3303 // So device-only functions are the only things we skip.
3304 if (isa<FunctionDecl>(Global) && !Global->hasAttr<CUDAHostAttr>() &&
3305 Global->hasAttr<CUDADeviceAttr>())
3306 return;
3307
3308 assert((isa<FunctionDecl>(Global) || isa<VarDecl>(Global)) &&
3309 "Expected Variable or Function");
3310 }
3311 }
3312
3313 if (LangOpts.OpenMP) {
3314 // If this is OpenMP, check if it is legal to emit this global normally.
3315 if (OpenMPRuntime && OpenMPRuntime->emitTargetGlobal(GD))
3316 return;
3317 if (auto *DRD = dyn_cast<OMPDeclareReductionDecl>(Global)) {
3318 if (MustBeEmitted(Global))
3319 EmitOMPDeclareReduction(DRD);
3320 return;
3321 } else if (auto *DMD = dyn_cast<OMPDeclareMapperDecl>(Global)) {
3322 if (MustBeEmitted(Global))
3323 EmitOMPDeclareMapper(DMD);
3324 return;
3325 }
3326 }
3327
3328 // Ignore declarations, they will be emitted on their first use.
3329 if (const auto *FD = dyn_cast<FunctionDecl>(Global)) {
3330 // Forward declarations are emitted lazily on first use.
3331 if (!FD->doesThisDeclarationHaveABody()) {
3332 if (!FD->doesDeclarationForceExternallyVisibleDefinition())
3333 return;
3334
3335 StringRef MangledName = getMangledName(GD);
3336
3337 // Compute the function info and LLVM type.
3338 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD);
3339 llvm::Type *Ty = getTypes().GetFunctionType(FI);
3340
3341 GetOrCreateLLVMFunction(MangledName, Ty, GD, /*ForVTable=*/false,
3342 /*DontDefer=*/false);
3343 return;
3344 }
3345 } else {
3346 const auto *VD = cast<VarDecl>(Global);
3347 assert(VD->isFileVarDecl() && "Cannot emit local var decl as global.");
3348 if (VD->isThisDeclarationADefinition() != VarDecl::Definition &&
3349 !Context.isMSStaticDataMemberInlineDefinition(VD)) {
3350 if (LangOpts.OpenMP) {
3351 // Emit declaration of the must-be-emitted declare target variable.
3352 if (std::optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res =
3353 OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(VD)) {
3354 bool UnifiedMemoryEnabled =
3355 getOpenMPRuntime().hasRequiresUnifiedSharedMemory();
3356 if ((*Res == OMPDeclareTargetDeclAttr::MT_To ||
3357 *Res == OMPDeclareTargetDeclAttr::MT_Enter) &&
3358 !UnifiedMemoryEnabled) {
3359 (void)GetAddrOfGlobalVar(VD);
3360 } else {
3361 assert(((*Res == OMPDeclareTargetDeclAttr::MT_Link) ||
3362 ((*Res == OMPDeclareTargetDeclAttr::MT_To ||
3363 *Res == OMPDeclareTargetDeclAttr::MT_Enter) &&
3364 UnifiedMemoryEnabled)) &&
3365 "Link clause or to clause with unified memory expected.");
3366 (void)getOpenMPRuntime().getAddrOfDeclareTargetVar(VD);
3367 }
3368
3369 return;
3370 }
3371 }
3372 // If this declaration may have caused an inline variable definition to
3373 // change linkage, make sure that it's emitted.
3374 if (Context.getInlineVariableDefinitionKind(VD) ==
3375 ASTContext::InlineVariableDefinitionKind::Strong)
3376 GetAddrOfGlobalVar(VD);
3377 return;
3378 }
3379 }
3380
3381 // Defer code generation to first use when possible, e.g. if this is an inline
3382 // function. If the global must always be emitted, do it eagerly if possible
3383 // to benefit from cache locality.
3384 if (MustBeEmitted(Global) && MayBeEmittedEagerly(Global)) {
3385 // Emit the definition if it can't be deferred.
3386 EmitGlobalDefinition(GD);
3387 return;
3388 }
3389
3390 // If we're deferring emission of a C++ variable with an
3391 // initializer, remember the order in which it appeared in the file.
3392 if (getLangOpts().CPlusPlus && isa<VarDecl>(Global) &&
3393 cast<VarDecl>(Global)->hasInit()) {
3394 DelayedCXXInitPosition[Global] = CXXGlobalInits.size();
3395 CXXGlobalInits.push_back(nullptr);
3396 }
3397
3398 StringRef MangledName = getMangledName(GD);
3399 if (GetGlobalValue(MangledName) != nullptr) {
3400 // The value has already been used and should therefore be emitted.
3401 addDeferredDeclToEmit(GD);
3402 } else if (MustBeEmitted(Global)) {
3403 // The value must be emitted, but cannot be emitted eagerly.
3404 assert(!MayBeEmittedEagerly(Global));
3405 addDeferredDeclToEmit(GD);
3406 EmittedDeferredDecls[MangledName] = GD;
3407 } else {
3408 // Otherwise, remember that we saw a deferred decl with this name. The
3409 // first use of the mangled name will cause it to move into
3410 // DeferredDeclsToEmit.
3411 DeferredDecls[MangledName] = GD;
3412 }
3413 }
3414
3415 // Check if T is a class type with a destructor that's not dllimport.
HasNonDllImportDtor(QualType T)3416 static bool HasNonDllImportDtor(QualType T) {
3417 if (const auto *RT = T->getBaseElementTypeUnsafe()->getAs<RecordType>())
3418 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
3419 if (RD->getDestructor() && !RD->getDestructor()->hasAttr<DLLImportAttr>())
3420 return true;
3421
3422 return false;
3423 }
3424
3425 namespace {
3426 struct FunctionIsDirectlyRecursive
3427 : public ConstStmtVisitor<FunctionIsDirectlyRecursive, bool> {
3428 const StringRef Name;
3429 const Builtin::Context &BI;
FunctionIsDirectlyRecursive__anonfb6b25460911::FunctionIsDirectlyRecursive3430 FunctionIsDirectlyRecursive(StringRef N, const Builtin::Context &C)
3431 : Name(N), BI(C) {}
3432
VisitCallExpr__anonfb6b25460911::FunctionIsDirectlyRecursive3433 bool VisitCallExpr(const CallExpr *E) {
3434 const FunctionDecl *FD = E->getDirectCallee();
3435 if (!FD)
3436 return false;
3437 AsmLabelAttr *Attr = FD->getAttr<AsmLabelAttr>();
3438 if (Attr && Name == Attr->getLabel())
3439 return true;
3440 unsigned BuiltinID = FD->getBuiltinID();
3441 if (!BuiltinID || !BI.isLibFunction(BuiltinID))
3442 return false;
3443 StringRef BuiltinName = BI.getName(BuiltinID);
3444 if (BuiltinName.startswith("__builtin_") &&
3445 Name == BuiltinName.slice(strlen("__builtin_"), StringRef::npos)) {
3446 return true;
3447 }
3448 return false;
3449 }
3450
VisitStmt__anonfb6b25460911::FunctionIsDirectlyRecursive3451 bool VisitStmt(const Stmt *S) {
3452 for (const Stmt *Child : S->children())
3453 if (Child && this->Visit(Child))
3454 return true;
3455 return false;
3456 }
3457 };
3458
3459 // Make sure we're not referencing non-imported vars or functions.
3460 struct DLLImportFunctionVisitor
3461 : public RecursiveASTVisitor<DLLImportFunctionVisitor> {
3462 bool SafeToInline = true;
3463
shouldVisitImplicitCode__anonfb6b25460911::DLLImportFunctionVisitor3464 bool shouldVisitImplicitCode() const { return true; }
3465
VisitVarDecl__anonfb6b25460911::DLLImportFunctionVisitor3466 bool VisitVarDecl(VarDecl *VD) {
3467 if (VD->getTLSKind()) {
3468 // A thread-local variable cannot be imported.
3469 SafeToInline = false;
3470 return SafeToInline;
3471 }
3472
3473 // A variable definition might imply a destructor call.
3474 if (VD->isThisDeclarationADefinition())
3475 SafeToInline = !HasNonDllImportDtor(VD->getType());
3476
3477 return SafeToInline;
3478 }
3479
VisitCXXBindTemporaryExpr__anonfb6b25460911::DLLImportFunctionVisitor3480 bool VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) {
3481 if (const auto *D = E->getTemporary()->getDestructor())
3482 SafeToInline = D->hasAttr<DLLImportAttr>();
3483 return SafeToInline;
3484 }
3485
VisitDeclRefExpr__anonfb6b25460911::DLLImportFunctionVisitor3486 bool VisitDeclRefExpr(DeclRefExpr *E) {
3487 ValueDecl *VD = E->getDecl();
3488 if (isa<FunctionDecl>(VD))
3489 SafeToInline = VD->hasAttr<DLLImportAttr>();
3490 else if (VarDecl *V = dyn_cast<VarDecl>(VD))
3491 SafeToInline = !V->hasGlobalStorage() || V->hasAttr<DLLImportAttr>();
3492 return SafeToInline;
3493 }
3494
VisitCXXConstructExpr__anonfb6b25460911::DLLImportFunctionVisitor3495 bool VisitCXXConstructExpr(CXXConstructExpr *E) {
3496 SafeToInline = E->getConstructor()->hasAttr<DLLImportAttr>();
3497 return SafeToInline;
3498 }
3499
VisitCXXMemberCallExpr__anonfb6b25460911::DLLImportFunctionVisitor3500 bool VisitCXXMemberCallExpr(CXXMemberCallExpr *E) {
3501 CXXMethodDecl *M = E->getMethodDecl();
3502 if (!M) {
3503 // Call through a pointer to member function. This is safe to inline.
3504 SafeToInline = true;
3505 } else {
3506 SafeToInline = M->hasAttr<DLLImportAttr>();
3507 }
3508 return SafeToInline;
3509 }
3510
VisitCXXDeleteExpr__anonfb6b25460911::DLLImportFunctionVisitor3511 bool VisitCXXDeleteExpr(CXXDeleteExpr *E) {
3512 SafeToInline = E->getOperatorDelete()->hasAttr<DLLImportAttr>();
3513 return SafeToInline;
3514 }
3515
VisitCXXNewExpr__anonfb6b25460911::DLLImportFunctionVisitor3516 bool VisitCXXNewExpr(CXXNewExpr *E) {
3517 SafeToInline = E->getOperatorNew()->hasAttr<DLLImportAttr>();
3518 return SafeToInline;
3519 }
3520 };
3521 }
3522
3523 // isTriviallyRecursive - Check if this function calls another
3524 // decl that, because of the asm attribute or the other decl being a builtin,
3525 // ends up pointing to itself.
3526 bool
isTriviallyRecursive(const FunctionDecl * FD)3527 CodeGenModule::isTriviallyRecursive(const FunctionDecl *FD) {
3528 StringRef Name;
3529 if (getCXXABI().getMangleContext().shouldMangleDeclName(FD)) {
3530 // asm labels are a special kind of mangling we have to support.
3531 AsmLabelAttr *Attr = FD->getAttr<AsmLabelAttr>();
3532 if (!Attr)
3533 return false;
3534 Name = Attr->getLabel();
3535 } else {
3536 Name = FD->getName();
3537 }
3538
3539 FunctionIsDirectlyRecursive Walker(Name, Context.BuiltinInfo);
3540 const Stmt *Body = FD->getBody();
3541 return Body ? Walker.Visit(Body) : false;
3542 }
3543
shouldEmitFunction(GlobalDecl GD)3544 bool CodeGenModule::shouldEmitFunction(GlobalDecl GD) {
3545 if (getFunctionLinkage(GD) != llvm::Function::AvailableExternallyLinkage)
3546 return true;
3547 const auto *F = cast<FunctionDecl>(GD.getDecl());
3548 if (CodeGenOpts.OptimizationLevel == 0 && !F->hasAttr<AlwaysInlineAttr>())
3549 return false;
3550
3551 if (F->hasAttr<DLLImportAttr>() && !F->hasAttr<AlwaysInlineAttr>()) {
3552 // Check whether it would be safe to inline this dllimport function.
3553 DLLImportFunctionVisitor Visitor;
3554 Visitor.TraverseFunctionDecl(const_cast<FunctionDecl*>(F));
3555 if (!Visitor.SafeToInline)
3556 return false;
3557
3558 if (const CXXDestructorDecl *Dtor = dyn_cast<CXXDestructorDecl>(F)) {
3559 // Implicit destructor invocations aren't captured in the AST, so the
3560 // check above can't see them. Check for them manually here.
3561 for (const Decl *Member : Dtor->getParent()->decls())
3562 if (isa<FieldDecl>(Member))
3563 if (HasNonDllImportDtor(cast<FieldDecl>(Member)->getType()))
3564 return false;
3565 for (const CXXBaseSpecifier &B : Dtor->getParent()->bases())
3566 if (HasNonDllImportDtor(B.getType()))
3567 return false;
3568 }
3569 }
3570
3571 // Inline builtins declaration must be emitted. They often are fortified
3572 // functions.
3573 if (F->isInlineBuiltinDeclaration())
3574 return true;
3575
3576 // PR9614. Avoid cases where the source code is lying to us. An available
3577 // externally function should have an equivalent function somewhere else,
3578 // but a function that calls itself through asm label/`__builtin_` trickery is
3579 // clearly not equivalent to the real implementation.
3580 // This happens in glibc's btowc and in some configure checks.
3581 return !isTriviallyRecursive(F);
3582 }
3583
shouldOpportunisticallyEmitVTables()3584 bool CodeGenModule::shouldOpportunisticallyEmitVTables() {
3585 return CodeGenOpts.OptimizationLevel > 0;
3586 }
3587
EmitMultiVersionFunctionDefinition(GlobalDecl GD,llvm::GlobalValue * GV)3588 void CodeGenModule::EmitMultiVersionFunctionDefinition(GlobalDecl GD,
3589 llvm::GlobalValue *GV) {
3590 const auto *FD = cast<FunctionDecl>(GD.getDecl());
3591
3592 if (FD->isCPUSpecificMultiVersion()) {
3593 auto *Spec = FD->getAttr<CPUSpecificAttr>();
3594 for (unsigned I = 0; I < Spec->cpus_size(); ++I)
3595 EmitGlobalFunctionDefinition(GD.getWithMultiVersionIndex(I), nullptr);
3596 } else if (FD->isTargetClonesMultiVersion()) {
3597 auto *Clone = FD->getAttr<TargetClonesAttr>();
3598 for (unsigned I = 0; I < Clone->featuresStrs_size(); ++I)
3599 if (Clone->isFirstOfVersion(I))
3600 EmitGlobalFunctionDefinition(GD.getWithMultiVersionIndex(I), nullptr);
3601 // Ensure that the resolver function is also emitted.
3602 GetOrCreateMultiVersionResolver(GD);
3603 } else
3604 EmitGlobalFunctionDefinition(GD, GV);
3605 }
3606
EmitGlobalDefinition(GlobalDecl GD,llvm::GlobalValue * GV)3607 void CodeGenModule::EmitGlobalDefinition(GlobalDecl GD, llvm::GlobalValue *GV) {
3608 const auto *D = cast<ValueDecl>(GD.getDecl());
3609
3610 PrettyStackTraceDecl CrashInfo(const_cast<ValueDecl *>(D), D->getLocation(),
3611 Context.getSourceManager(),
3612 "Generating code for declaration");
3613
3614 if (const auto *FD = dyn_cast<FunctionDecl>(D)) {
3615 // At -O0, don't generate IR for functions with available_externally
3616 // linkage.
3617 if (!shouldEmitFunction(GD))
3618 return;
3619
3620 llvm::TimeTraceScope TimeScope("CodeGen Function", [&]() {
3621 std::string Name;
3622 llvm::raw_string_ostream OS(Name);
3623 FD->getNameForDiagnostic(OS, getContext().getPrintingPolicy(),
3624 /*Qualified=*/true);
3625 return Name;
3626 });
3627
3628 if (const auto *Method = dyn_cast<CXXMethodDecl>(D)) {
3629 // Make sure to emit the definition(s) before we emit the thunks.
3630 // This is necessary for the generation of certain thunks.
3631 if (isa<CXXConstructorDecl>(Method) || isa<CXXDestructorDecl>(Method))
3632 ABI->emitCXXStructor(GD);
3633 else if (FD->isMultiVersion())
3634 EmitMultiVersionFunctionDefinition(GD, GV);
3635 else
3636 EmitGlobalFunctionDefinition(GD, GV);
3637
3638 if (Method->isVirtual())
3639 getVTables().EmitThunks(GD);
3640
3641 return;
3642 }
3643
3644 if (FD->isMultiVersion())
3645 return EmitMultiVersionFunctionDefinition(GD, GV);
3646 return EmitGlobalFunctionDefinition(GD, GV);
3647 }
3648
3649 if (const auto *VD = dyn_cast<VarDecl>(D))
3650 return EmitGlobalVarDefinition(VD, !VD->hasDefinition());
3651
3652 llvm_unreachable("Invalid argument to EmitGlobalDefinition()");
3653 }
3654
3655 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old,
3656 llvm::Function *NewFn);
3657
3658 static unsigned
TargetMVPriority(const TargetInfo & TI,const CodeGenFunction::MultiVersionResolverOption & RO)3659 TargetMVPriority(const TargetInfo &TI,
3660 const CodeGenFunction::MultiVersionResolverOption &RO) {
3661 unsigned Priority = 0;
3662 unsigned NumFeatures = 0;
3663 for (StringRef Feat : RO.Conditions.Features) {
3664 Priority = std::max(Priority, TI.multiVersionSortPriority(Feat));
3665 NumFeatures++;
3666 }
3667
3668 if (!RO.Conditions.Architecture.empty())
3669 Priority = std::max(
3670 Priority, TI.multiVersionSortPriority(RO.Conditions.Architecture));
3671
3672 Priority += TI.multiVersionFeatureCost() * NumFeatures;
3673
3674 return Priority;
3675 }
3676
3677 // Multiversion functions should be at most 'WeakODRLinkage' so that a different
3678 // TU can forward declare the function without causing problems. Particularly
3679 // in the cases of CPUDispatch, this causes issues. This also makes sure we
3680 // work with internal linkage functions, so that the same function name can be
3681 // used with internal linkage in multiple TUs.
getMultiversionLinkage(CodeGenModule & CGM,GlobalDecl GD)3682 llvm::GlobalValue::LinkageTypes getMultiversionLinkage(CodeGenModule &CGM,
3683 GlobalDecl GD) {
3684 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
3685 if (FD->getFormalLinkage() == InternalLinkage)
3686 return llvm::GlobalValue::InternalLinkage;
3687 return llvm::GlobalValue::WeakODRLinkage;
3688 }
3689
emitMultiVersionFunctions()3690 void CodeGenModule::emitMultiVersionFunctions() {
3691 std::vector<GlobalDecl> MVFuncsToEmit;
3692 MultiVersionFuncs.swap(MVFuncsToEmit);
3693 for (GlobalDecl GD : MVFuncsToEmit) {
3694 const auto *FD = cast<FunctionDecl>(GD.getDecl());
3695 assert(FD && "Expected a FunctionDecl");
3696
3697 SmallVector<CodeGenFunction::MultiVersionResolverOption, 10> Options;
3698 if (FD->isTargetMultiVersion()) {
3699 getContext().forEachMultiversionedFunctionVersion(
3700 FD, [this, &GD, &Options](const FunctionDecl *CurFD) {
3701 GlobalDecl CurGD{
3702 (CurFD->isDefined() ? CurFD->getDefinition() : CurFD)};
3703 StringRef MangledName = getMangledName(CurGD);
3704 llvm::Constant *Func = GetGlobalValue(MangledName);
3705 if (!Func) {
3706 if (CurFD->isDefined()) {
3707 EmitGlobalFunctionDefinition(CurGD, nullptr);
3708 Func = GetGlobalValue(MangledName);
3709 } else {
3710 const CGFunctionInfo &FI =
3711 getTypes().arrangeGlobalDeclaration(GD);
3712 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI);
3713 Func = GetAddrOfFunction(CurGD, Ty, /*ForVTable=*/false,
3714 /*DontDefer=*/false, ForDefinition);
3715 }
3716 assert(Func && "This should have just been created");
3717 }
3718 if (CurFD->getMultiVersionKind() == MultiVersionKind::Target) {
3719 const auto *TA = CurFD->getAttr<TargetAttr>();
3720 llvm::SmallVector<StringRef, 8> Feats;
3721 TA->getAddedFeatures(Feats);
3722 Options.emplace_back(cast<llvm::Function>(Func),
3723 TA->getArchitecture(), Feats);
3724 } else {
3725 const auto *TVA = CurFD->getAttr<TargetVersionAttr>();
3726 llvm::SmallVector<StringRef, 8> Feats;
3727 TVA->getFeatures(Feats);
3728 Options.emplace_back(cast<llvm::Function>(Func),
3729 /*Architecture*/ "", Feats);
3730 }
3731 });
3732 } else if (FD->isTargetClonesMultiVersion()) {
3733 const auto *TC = FD->getAttr<TargetClonesAttr>();
3734 for (unsigned VersionIndex = 0; VersionIndex < TC->featuresStrs_size();
3735 ++VersionIndex) {
3736 if (!TC->isFirstOfVersion(VersionIndex))
3737 continue;
3738 GlobalDecl CurGD{(FD->isDefined() ? FD->getDefinition() : FD),
3739 VersionIndex};
3740 StringRef Version = TC->getFeatureStr(VersionIndex);
3741 StringRef MangledName = getMangledName(CurGD);
3742 llvm::Constant *Func = GetGlobalValue(MangledName);
3743 if (!Func) {
3744 if (FD->isDefined()) {
3745 EmitGlobalFunctionDefinition(CurGD, nullptr);
3746 Func = GetGlobalValue(MangledName);
3747 } else {
3748 const CGFunctionInfo &FI =
3749 getTypes().arrangeGlobalDeclaration(CurGD);
3750 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI);
3751 Func = GetAddrOfFunction(CurGD, Ty, /*ForVTable=*/false,
3752 /*DontDefer=*/false, ForDefinition);
3753 }
3754 assert(Func && "This should have just been created");
3755 }
3756
3757 StringRef Architecture;
3758 llvm::SmallVector<StringRef, 1> Feature;
3759
3760 if (getTarget().getTriple().isAArch64()) {
3761 if (Version != "default") {
3762 llvm::SmallVector<StringRef, 8> VerFeats;
3763 Version.split(VerFeats, "+");
3764 for (auto &CurFeat : VerFeats)
3765 Feature.push_back(CurFeat.trim());
3766 }
3767 } else {
3768 if (Version.startswith("arch="))
3769 Architecture = Version.drop_front(sizeof("arch=") - 1);
3770 else if (Version != "default")
3771 Feature.push_back(Version);
3772 }
3773
3774 Options.emplace_back(cast<llvm::Function>(Func), Architecture, Feature);
3775 }
3776 } else {
3777 assert(0 && "Expected a target or target_clones multiversion function");
3778 continue;
3779 }
3780
3781 llvm::Constant *ResolverConstant = GetOrCreateMultiVersionResolver(GD);
3782 if (auto *IFunc = dyn_cast<llvm::GlobalIFunc>(ResolverConstant))
3783 ResolverConstant = IFunc->getResolver();
3784 llvm::Function *ResolverFunc = cast<llvm::Function>(ResolverConstant);
3785
3786 ResolverFunc->setLinkage(getMultiversionLinkage(*this, GD));
3787
3788 if (supportsCOMDAT())
3789 ResolverFunc->setComdat(
3790 getModule().getOrInsertComdat(ResolverFunc->getName()));
3791
3792 const TargetInfo &TI = getTarget();
3793 llvm::stable_sort(
3794 Options, [&TI](const CodeGenFunction::MultiVersionResolverOption &LHS,
3795 const CodeGenFunction::MultiVersionResolverOption &RHS) {
3796 return TargetMVPriority(TI, LHS) > TargetMVPriority(TI, RHS);
3797 });
3798 CodeGenFunction CGF(*this);
3799 CGF.EmitMultiVersionResolver(ResolverFunc, Options);
3800 }
3801
3802 // Ensure that any additions to the deferred decls list caused by emitting a
3803 // variant are emitted. This can happen when the variant itself is inline and
3804 // calls a function without linkage.
3805 if (!MVFuncsToEmit.empty())
3806 EmitDeferred();
3807
3808 // Ensure that any additions to the multiversion funcs list from either the
3809 // deferred decls or the multiversion functions themselves are emitted.
3810 if (!MultiVersionFuncs.empty())
3811 emitMultiVersionFunctions();
3812 }
3813
emitCPUDispatchDefinition(GlobalDecl GD)3814 void CodeGenModule::emitCPUDispatchDefinition(GlobalDecl GD) {
3815 const auto *FD = cast<FunctionDecl>(GD.getDecl());
3816 assert(FD && "Not a FunctionDecl?");
3817 assert(FD->isCPUDispatchMultiVersion() && "Not a multiversion function?");
3818 const auto *DD = FD->getAttr<CPUDispatchAttr>();
3819 assert(DD && "Not a cpu_dispatch Function?");
3820
3821 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD);
3822 llvm::FunctionType *DeclTy = getTypes().GetFunctionType(FI);
3823
3824 StringRef ResolverName = getMangledName(GD);
3825 UpdateMultiVersionNames(GD, FD, ResolverName);
3826
3827 llvm::Type *ResolverType;
3828 GlobalDecl ResolverGD;
3829 if (getTarget().supportsIFunc()) {
3830 ResolverType = llvm::FunctionType::get(
3831 llvm::PointerType::get(DeclTy,
3832 getTypes().getTargetAddressSpace(FD->getType())),
3833 false);
3834 }
3835 else {
3836 ResolverType = DeclTy;
3837 ResolverGD = GD;
3838 }
3839
3840 auto *ResolverFunc = cast<llvm::Function>(GetOrCreateLLVMFunction(
3841 ResolverName, ResolverType, ResolverGD, /*ForVTable=*/false));
3842 ResolverFunc->setLinkage(getMultiversionLinkage(*this, GD));
3843 if (supportsCOMDAT())
3844 ResolverFunc->setComdat(
3845 getModule().getOrInsertComdat(ResolverFunc->getName()));
3846
3847 SmallVector<CodeGenFunction::MultiVersionResolverOption, 10> Options;
3848 const TargetInfo &Target = getTarget();
3849 unsigned Index = 0;
3850 for (const IdentifierInfo *II : DD->cpus()) {
3851 // Get the name of the target function so we can look it up/create it.
3852 std::string MangledName = getMangledNameImpl(*this, GD, FD, true) +
3853 getCPUSpecificMangling(*this, II->getName());
3854
3855 llvm::Constant *Func = GetGlobalValue(MangledName);
3856
3857 if (!Func) {
3858 GlobalDecl ExistingDecl = Manglings.lookup(MangledName);
3859 if (ExistingDecl.getDecl() &&
3860 ExistingDecl.getDecl()->getAsFunction()->isDefined()) {
3861 EmitGlobalFunctionDefinition(ExistingDecl, nullptr);
3862 Func = GetGlobalValue(MangledName);
3863 } else {
3864 if (!ExistingDecl.getDecl())
3865 ExistingDecl = GD.getWithMultiVersionIndex(Index);
3866
3867 Func = GetOrCreateLLVMFunction(
3868 MangledName, DeclTy, ExistingDecl,
3869 /*ForVTable=*/false, /*DontDefer=*/true,
3870 /*IsThunk=*/false, llvm::AttributeList(), ForDefinition);
3871 }
3872 }
3873
3874 llvm::SmallVector<StringRef, 32> Features;
3875 Target.getCPUSpecificCPUDispatchFeatures(II->getName(), Features);
3876 llvm::transform(Features, Features.begin(),
3877 [](StringRef Str) { return Str.substr(1); });
3878 llvm::erase_if(Features, [&Target](StringRef Feat) {
3879 return !Target.validateCpuSupports(Feat);
3880 });
3881 Options.emplace_back(cast<llvm::Function>(Func), StringRef{}, Features);
3882 ++Index;
3883 }
3884
3885 llvm::stable_sort(
3886 Options, [](const CodeGenFunction::MultiVersionResolverOption &LHS,
3887 const CodeGenFunction::MultiVersionResolverOption &RHS) {
3888 return llvm::X86::getCpuSupportsMask(LHS.Conditions.Features) >
3889 llvm::X86::getCpuSupportsMask(RHS.Conditions.Features);
3890 });
3891
3892 // If the list contains multiple 'default' versions, such as when it contains
3893 // 'pentium' and 'generic', don't emit the call to the generic one (since we
3894 // always run on at least a 'pentium'). We do this by deleting the 'least
3895 // advanced' (read, lowest mangling letter).
3896 while (Options.size() > 1 &&
3897 llvm::X86::getCpuSupportsMask(
3898 (Options.end() - 2)->Conditions.Features) == 0) {
3899 StringRef LHSName = (Options.end() - 2)->Function->getName();
3900 StringRef RHSName = (Options.end() - 1)->Function->getName();
3901 if (LHSName.compare(RHSName) < 0)
3902 Options.erase(Options.end() - 2);
3903 else
3904 Options.erase(Options.end() - 1);
3905 }
3906
3907 CodeGenFunction CGF(*this);
3908 CGF.EmitMultiVersionResolver(ResolverFunc, Options);
3909
3910 if (getTarget().supportsIFunc()) {
3911 llvm::GlobalValue::LinkageTypes Linkage = getMultiversionLinkage(*this, GD);
3912 auto *IFunc = cast<llvm::GlobalValue>(GetOrCreateMultiVersionResolver(GD));
3913
3914 // Fix up function declarations that were created for cpu_specific before
3915 // cpu_dispatch was known
3916 if (!isa<llvm::GlobalIFunc>(IFunc)) {
3917 assert(cast<llvm::Function>(IFunc)->isDeclaration());
3918 auto *GI = llvm::GlobalIFunc::create(DeclTy, 0, Linkage, "", ResolverFunc,
3919 &getModule());
3920 GI->takeName(IFunc);
3921 IFunc->replaceAllUsesWith(GI);
3922 IFunc->eraseFromParent();
3923 IFunc = GI;
3924 }
3925
3926 std::string AliasName = getMangledNameImpl(
3927 *this, GD, FD, /*OmitMultiVersionMangling=*/true);
3928 llvm::Constant *AliasFunc = GetGlobalValue(AliasName);
3929 if (!AliasFunc) {
3930 auto *GA = llvm::GlobalAlias::create(DeclTy, 0, Linkage, AliasName, IFunc,
3931 &getModule());
3932 SetCommonAttributes(GD, GA);
3933 }
3934 }
3935 }
3936
3937 /// If a dispatcher for the specified mangled name is not in the module, create
3938 /// and return an llvm Function with the specified type.
GetOrCreateMultiVersionResolver(GlobalDecl GD)3939 llvm::Constant *CodeGenModule::GetOrCreateMultiVersionResolver(GlobalDecl GD) {
3940 const auto *FD = cast<FunctionDecl>(GD.getDecl());
3941 assert(FD && "Not a FunctionDecl?");
3942
3943 std::string MangledName =
3944 getMangledNameImpl(*this, GD, FD, /*OmitMultiVersionMangling=*/true);
3945
3946 // Holds the name of the resolver, in ifunc mode this is the ifunc (which has
3947 // a separate resolver).
3948 std::string ResolverName = MangledName;
3949 if (getTarget().supportsIFunc())
3950 ResolverName += ".ifunc";
3951 else if (FD->isTargetMultiVersion())
3952 ResolverName += ".resolver";
3953
3954 // If the resolver has already been created, just return it.
3955 if (llvm::GlobalValue *ResolverGV = GetGlobalValue(ResolverName))
3956 return ResolverGV;
3957
3958 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD);
3959 llvm::FunctionType *DeclTy = getTypes().GetFunctionType(FI);
3960
3961 // The resolver needs to be created. For target and target_clones, defer
3962 // creation until the end of the TU.
3963 if (FD->isTargetMultiVersion() || FD->isTargetClonesMultiVersion())
3964 MultiVersionFuncs.push_back(GD);
3965
3966 // For cpu_specific, don't create an ifunc yet because we don't know if the
3967 // cpu_dispatch will be emitted in this translation unit.
3968 if (getTarget().supportsIFunc() && !FD->isCPUSpecificMultiVersion()) {
3969 llvm::Type *ResolverType = llvm::FunctionType::get(
3970 llvm::PointerType::get(DeclTy,
3971 getTypes().getTargetAddressSpace(FD->getType())),
3972 false);
3973 llvm::Constant *Resolver = GetOrCreateLLVMFunction(
3974 MangledName + ".resolver", ResolverType, GlobalDecl{},
3975 /*ForVTable=*/false);
3976 llvm::GlobalIFunc *GIF =
3977 llvm::GlobalIFunc::create(DeclTy, 0, getMultiversionLinkage(*this, GD),
3978 "", Resolver, &getModule());
3979 GIF->setName(ResolverName);
3980 SetCommonAttributes(FD, GIF);
3981
3982 return GIF;
3983 }
3984
3985 llvm::Constant *Resolver = GetOrCreateLLVMFunction(
3986 ResolverName, DeclTy, GlobalDecl{}, /*ForVTable=*/false);
3987 assert(isa<llvm::GlobalValue>(Resolver) &&
3988 "Resolver should be created for the first time");
3989 SetCommonAttributes(FD, cast<llvm::GlobalValue>(Resolver));
3990 return Resolver;
3991 }
3992
3993 /// GetOrCreateLLVMFunction - If the specified mangled name is not in the
3994 /// module, create and return an llvm Function with the specified type. If there
3995 /// is something in the module with the specified name, return it potentially
3996 /// bitcasted to the right type.
3997 ///
3998 /// If D is non-null, it specifies a decl that correspond to this. This is used
3999 /// to set the attributes on the function when it is first created.
GetOrCreateLLVMFunction(StringRef MangledName,llvm::Type * Ty,GlobalDecl GD,bool ForVTable,bool DontDefer,bool IsThunk,llvm::AttributeList ExtraAttrs,ForDefinition_t IsForDefinition)4000 llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction(
4001 StringRef MangledName, llvm::Type *Ty, GlobalDecl GD, bool ForVTable,
4002 bool DontDefer, bool IsThunk, llvm::AttributeList ExtraAttrs,
4003 ForDefinition_t IsForDefinition) {
4004 const Decl *D = GD.getDecl();
4005
4006 // Any attempts to use a MultiVersion function should result in retrieving
4007 // the iFunc instead. Name Mangling will handle the rest of the changes.
4008 if (const FunctionDecl *FD = cast_or_null<FunctionDecl>(D)) {
4009 // For the device mark the function as one that should be emitted.
4010 if (getLangOpts().OpenMPIsDevice && OpenMPRuntime &&
4011 !OpenMPRuntime->markAsGlobalTarget(GD) && FD->isDefined() &&
4012 !DontDefer && !IsForDefinition) {
4013 if (const FunctionDecl *FDDef = FD->getDefinition()) {
4014 GlobalDecl GDDef;
4015 if (const auto *CD = dyn_cast<CXXConstructorDecl>(FDDef))
4016 GDDef = GlobalDecl(CD, GD.getCtorType());
4017 else if (const auto *DD = dyn_cast<CXXDestructorDecl>(FDDef))
4018 GDDef = GlobalDecl(DD, GD.getDtorType());
4019 else
4020 GDDef = GlobalDecl(FDDef);
4021 EmitGlobal(GDDef);
4022 }
4023 }
4024
4025 if (FD->isMultiVersion()) {
4026 UpdateMultiVersionNames(GD, FD, MangledName);
4027 if (!IsForDefinition)
4028 return GetOrCreateMultiVersionResolver(GD);
4029 }
4030 }
4031
4032 // Lookup the entry, lazily creating it if necessary.
4033 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
4034 if (Entry) {
4035 if (WeakRefReferences.erase(Entry)) {
4036 const FunctionDecl *FD = cast_or_null<FunctionDecl>(D);
4037 if (FD && !FD->hasAttr<WeakAttr>())
4038 Entry->setLinkage(llvm::Function::ExternalLinkage);
4039 }
4040
4041 // Handle dropped DLL attributes.
4042 if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>() &&
4043 !shouldMapVisibilityToDLLExport(cast_or_null<NamedDecl>(D))) {
4044 Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
4045 setDSOLocal(Entry);
4046 }
4047
4048 // If there are two attempts to define the same mangled name, issue an
4049 // error.
4050 if (IsForDefinition && !Entry->isDeclaration()) {
4051 GlobalDecl OtherGD;
4052 // Check that GD is not yet in DiagnosedConflictingDefinitions is required
4053 // to make sure that we issue an error only once.
4054 if (lookupRepresentativeDecl(MangledName, OtherGD) &&
4055 (GD.getCanonicalDecl().getDecl() !=
4056 OtherGD.getCanonicalDecl().getDecl()) &&
4057 DiagnosedConflictingDefinitions.insert(GD).second) {
4058 getDiags().Report(D->getLocation(), diag::err_duplicate_mangled_name)
4059 << MangledName;
4060 getDiags().Report(OtherGD.getDecl()->getLocation(),
4061 diag::note_previous_definition);
4062 }
4063 }
4064
4065 if ((isa<llvm::Function>(Entry) || isa<llvm::GlobalAlias>(Entry)) &&
4066 (Entry->getValueType() == Ty)) {
4067 return Entry;
4068 }
4069
4070 // Make sure the result is of the correct type.
4071 // (If function is requested for a definition, we always need to create a new
4072 // function, not just return a bitcast.)
4073 if (!IsForDefinition)
4074 return llvm::ConstantExpr::getBitCast(
4075 Entry, Ty->getPointerTo(Entry->getAddressSpace()));
4076 }
4077
4078 // This function doesn't have a complete type (for example, the return
4079 // type is an incomplete struct). Use a fake type instead, and make
4080 // sure not to try to set attributes.
4081 bool IsIncompleteFunction = false;
4082
4083 llvm::FunctionType *FTy;
4084 if (isa<llvm::FunctionType>(Ty)) {
4085 FTy = cast<llvm::FunctionType>(Ty);
4086 } else {
4087 FTy = llvm::FunctionType::get(VoidTy, false);
4088 IsIncompleteFunction = true;
4089 }
4090
4091 llvm::Function *F =
4092 llvm::Function::Create(FTy, llvm::Function::ExternalLinkage,
4093 Entry ? StringRef() : MangledName, &getModule());
4094
4095 // If we already created a function with the same mangled name (but different
4096 // type) before, take its name and add it to the list of functions to be
4097 // replaced with F at the end of CodeGen.
4098 //
4099 // This happens if there is a prototype for a function (e.g. "int f()") and
4100 // then a definition of a different type (e.g. "int f(int x)").
4101 if (Entry) {
4102 F->takeName(Entry);
4103
4104 // This might be an implementation of a function without a prototype, in
4105 // which case, try to do special replacement of calls which match the new
4106 // prototype. The really key thing here is that we also potentially drop
4107 // arguments from the call site so as to make a direct call, which makes the
4108 // inliner happier and suppresses a number of optimizer warnings (!) about
4109 // dropping arguments.
4110 if (!Entry->use_empty()) {
4111 ReplaceUsesOfNonProtoTypeWithRealFunction(Entry, F);
4112 Entry->removeDeadConstantUsers();
4113 }
4114
4115 llvm::Constant *BC = llvm::ConstantExpr::getBitCast(
4116 F, Entry->getValueType()->getPointerTo(Entry->getAddressSpace()));
4117 addGlobalValReplacement(Entry, BC);
4118 }
4119
4120 assert(F->getName() == MangledName && "name was uniqued!");
4121 if (D)
4122 SetFunctionAttributes(GD, F, IsIncompleteFunction, IsThunk);
4123 if (ExtraAttrs.hasFnAttrs()) {
4124 llvm::AttrBuilder B(F->getContext(), ExtraAttrs.getFnAttrs());
4125 F->addFnAttrs(B);
4126 }
4127
4128 if (!DontDefer) {
4129 // All MSVC dtors other than the base dtor are linkonce_odr and delegate to
4130 // each other bottoming out with the base dtor. Therefore we emit non-base
4131 // dtors on usage, even if there is no dtor definition in the TU.
4132 if (isa_and_nonnull<CXXDestructorDecl>(D) &&
4133 getCXXABI().useThunkForDtorVariant(cast<CXXDestructorDecl>(D),
4134 GD.getDtorType()))
4135 addDeferredDeclToEmit(GD);
4136
4137 // This is the first use or definition of a mangled name. If there is a
4138 // deferred decl with this name, remember that we need to emit it at the end
4139 // of the file.
4140 auto DDI = DeferredDecls.find(MangledName);
4141 if (DDI != DeferredDecls.end()) {
4142 // Move the potentially referenced deferred decl to the
4143 // DeferredDeclsToEmit list, and remove it from DeferredDecls (since we
4144 // don't need it anymore).
4145 addDeferredDeclToEmit(DDI->second);
4146 EmittedDeferredDecls[DDI->first] = DDI->second;
4147 DeferredDecls.erase(DDI);
4148
4149 // Otherwise, there are cases we have to worry about where we're
4150 // using a declaration for which we must emit a definition but where
4151 // we might not find a top-level definition:
4152 // - member functions defined inline in their classes
4153 // - friend functions defined inline in some class
4154 // - special member functions with implicit definitions
4155 // If we ever change our AST traversal to walk into class methods,
4156 // this will be unnecessary.
4157 //
4158 // We also don't emit a definition for a function if it's going to be an
4159 // entry in a vtable, unless it's already marked as used.
4160 } else if (getLangOpts().CPlusPlus && D) {
4161 // Look for a declaration that's lexically in a record.
4162 for (const auto *FD = cast<FunctionDecl>(D)->getMostRecentDecl(); FD;
4163 FD = FD->getPreviousDecl()) {
4164 if (isa<CXXRecordDecl>(FD->getLexicalDeclContext())) {
4165 if (FD->doesThisDeclarationHaveABody()) {
4166 addDeferredDeclToEmit(GD.getWithDecl(FD));
4167 break;
4168 }
4169 }
4170 }
4171 }
4172 }
4173
4174 // Make sure the result is of the requested type.
4175 if (!IsIncompleteFunction) {
4176 assert(F->getFunctionType() == Ty);
4177 return F;
4178 }
4179
4180 return llvm::ConstantExpr::getBitCast(F,
4181 Ty->getPointerTo(F->getAddressSpace()));
4182 }
4183
4184 /// GetAddrOfFunction - Return the address of the given function. If Ty is
4185 /// non-null, then this function will use the specified type if it has to
4186 /// create it (this occurs when we see a definition of the function).
GetAddrOfFunction(GlobalDecl GD,llvm::Type * Ty,bool ForVTable,bool DontDefer,ForDefinition_t IsForDefinition)4187 llvm::Constant *CodeGenModule::GetAddrOfFunction(GlobalDecl GD,
4188 llvm::Type *Ty,
4189 bool ForVTable,
4190 bool DontDefer,
4191 ForDefinition_t IsForDefinition) {
4192 assert(!cast<FunctionDecl>(GD.getDecl())->isConsteval() &&
4193 "consteval function should never be emitted");
4194 // If there was no specific requested type, just convert it now.
4195 if (!Ty) {
4196 const auto *FD = cast<FunctionDecl>(GD.getDecl());
4197 Ty = getTypes().ConvertType(FD->getType());
4198 }
4199
4200 // Devirtualized destructor calls may come through here instead of via
4201 // getAddrOfCXXStructor. Make sure we use the MS ABI base destructor instead
4202 // of the complete destructor when necessary.
4203 if (const auto *DD = dyn_cast<CXXDestructorDecl>(GD.getDecl())) {
4204 if (getTarget().getCXXABI().isMicrosoft() &&
4205 GD.getDtorType() == Dtor_Complete &&
4206 DD->getParent()->getNumVBases() == 0)
4207 GD = GlobalDecl(DD, Dtor_Base);
4208 }
4209
4210 StringRef MangledName = getMangledName(GD);
4211 auto *F = GetOrCreateLLVMFunction(MangledName, Ty, GD, ForVTable, DontDefer,
4212 /*IsThunk=*/false, llvm::AttributeList(),
4213 IsForDefinition);
4214 // Returns kernel handle for HIP kernel stub function.
4215 if (LangOpts.CUDA && !LangOpts.CUDAIsDevice &&
4216 cast<FunctionDecl>(GD.getDecl())->hasAttr<CUDAGlobalAttr>()) {
4217 auto *Handle = getCUDARuntime().getKernelHandle(
4218 cast<llvm::Function>(F->stripPointerCasts()), GD);
4219 if (IsForDefinition)
4220 return F;
4221 return llvm::ConstantExpr::getBitCast(Handle, Ty->getPointerTo());
4222 }
4223 return F;
4224 }
4225
GetFunctionStart(const ValueDecl * Decl)4226 llvm::Constant *CodeGenModule::GetFunctionStart(const ValueDecl *Decl) {
4227 llvm::GlobalValue *F =
4228 cast<llvm::GlobalValue>(GetAddrOfFunction(Decl)->stripPointerCasts());
4229
4230 return llvm::ConstantExpr::getBitCast(
4231 llvm::NoCFIValue::get(F),
4232 llvm::Type::getInt8PtrTy(VMContext, F->getAddressSpace()));
4233 }
4234
4235 static const FunctionDecl *
GetRuntimeFunctionDecl(ASTContext & C,StringRef Name)4236 GetRuntimeFunctionDecl(ASTContext &C, StringRef Name) {
4237 TranslationUnitDecl *TUDecl = C.getTranslationUnitDecl();
4238 DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl);
4239
4240 IdentifierInfo &CII = C.Idents.get(Name);
4241 for (const auto *Result : DC->lookup(&CII))
4242 if (const auto *FD = dyn_cast<FunctionDecl>(Result))
4243 return FD;
4244
4245 if (!C.getLangOpts().CPlusPlus)
4246 return nullptr;
4247
4248 // Demangle the premangled name from getTerminateFn()
4249 IdentifierInfo &CXXII =
4250 (Name == "_ZSt9terminatev" || Name == "?terminate@@YAXXZ")
4251 ? C.Idents.get("terminate")
4252 : C.Idents.get(Name);
4253
4254 for (const auto &N : {"__cxxabiv1", "std"}) {
4255 IdentifierInfo &NS = C.Idents.get(N);
4256 for (const auto *Result : DC->lookup(&NS)) {
4257 const NamespaceDecl *ND = dyn_cast<NamespaceDecl>(Result);
4258 if (auto *LSD = dyn_cast<LinkageSpecDecl>(Result))
4259 for (const auto *Result : LSD->lookup(&NS))
4260 if ((ND = dyn_cast<NamespaceDecl>(Result)))
4261 break;
4262
4263 if (ND)
4264 for (const auto *Result : ND->lookup(&CXXII))
4265 if (const auto *FD = dyn_cast<FunctionDecl>(Result))
4266 return FD;
4267 }
4268 }
4269
4270 return nullptr;
4271 }
4272
4273 /// CreateRuntimeFunction - Create a new runtime function with the specified
4274 /// type and name.
4275 llvm::FunctionCallee
CreateRuntimeFunction(llvm::FunctionType * FTy,StringRef Name,llvm::AttributeList ExtraAttrs,bool Local,bool AssumeConvergent)4276 CodeGenModule::CreateRuntimeFunction(llvm::FunctionType *FTy, StringRef Name,
4277 llvm::AttributeList ExtraAttrs, bool Local,
4278 bool AssumeConvergent) {
4279 if (AssumeConvergent) {
4280 ExtraAttrs =
4281 ExtraAttrs.addFnAttribute(VMContext, llvm::Attribute::Convergent);
4282 }
4283
4284 llvm::Constant *C =
4285 GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(), /*ForVTable=*/false,
4286 /*DontDefer=*/false, /*IsThunk=*/false,
4287 ExtraAttrs);
4288
4289 if (auto *F = dyn_cast<llvm::Function>(C)) {
4290 if (F->empty()) {
4291 F->setCallingConv(getRuntimeCC());
4292
4293 // In Windows Itanium environments, try to mark runtime functions
4294 // dllimport. For Mingw and MSVC, don't. We don't really know if the user
4295 // will link their standard library statically or dynamically. Marking
4296 // functions imported when they are not imported can cause linker errors
4297 // and warnings.
4298 if (!Local && getTriple().isWindowsItaniumEnvironment() &&
4299 !getCodeGenOpts().LTOVisibilityPublicStd) {
4300 const FunctionDecl *FD = GetRuntimeFunctionDecl(Context, Name);
4301 if (!FD || FD->hasAttr<DLLImportAttr>()) {
4302 F->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
4303 F->setLinkage(llvm::GlobalValue::ExternalLinkage);
4304 }
4305 }
4306 setDSOLocal(F);
4307 }
4308 }
4309
4310 return {FTy, C};
4311 }
4312
4313 /// isTypeConstant - Determine whether an object of this type can be emitted
4314 /// as a constant.
4315 ///
4316 /// If ExcludeCtor is true, the duration when the object's constructor runs
4317 /// will not be considered. The caller will need to verify that the object is
4318 /// not written to during its construction.
isTypeConstant(QualType Ty,bool ExcludeCtor)4319 bool CodeGenModule::isTypeConstant(QualType Ty, bool ExcludeCtor) {
4320 if (!Ty.isConstant(Context) && !Ty->isReferenceType())
4321 return false;
4322
4323 if (Context.getLangOpts().CPlusPlus) {
4324 if (const CXXRecordDecl *Record
4325 = Context.getBaseElementType(Ty)->getAsCXXRecordDecl())
4326 return ExcludeCtor && !Record->hasMutableFields() &&
4327 Record->hasTrivialDestructor();
4328 }
4329
4330 return true;
4331 }
4332
4333 /// GetOrCreateLLVMGlobal - If the specified mangled name is not in the module,
4334 /// create and return an llvm GlobalVariable with the specified type and address
4335 /// space. If there is something in the module with the specified name, return
4336 /// it potentially bitcasted to the right type.
4337 ///
4338 /// If D is non-null, it specifies a decl that correspond to this. This is used
4339 /// to set the attributes on the global when it is first created.
4340 ///
4341 /// If IsForDefinition is true, it is guaranteed that an actual global with
4342 /// type Ty will be returned, not conversion of a variable with the same
4343 /// mangled name but some other type.
4344 llvm::Constant *
GetOrCreateLLVMGlobal(StringRef MangledName,llvm::Type * Ty,LangAS AddrSpace,const VarDecl * D,ForDefinition_t IsForDefinition)4345 CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, llvm::Type *Ty,
4346 LangAS AddrSpace, const VarDecl *D,
4347 ForDefinition_t IsForDefinition) {
4348 // Lookup the entry, lazily creating it if necessary.
4349 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
4350 unsigned TargetAS = getContext().getTargetAddressSpace(AddrSpace);
4351 if (Entry) {
4352 if (WeakRefReferences.erase(Entry)) {
4353 if (D && !D->hasAttr<WeakAttr>())
4354 Entry->setLinkage(llvm::Function::ExternalLinkage);
4355 }
4356
4357 // Handle dropped DLL attributes.
4358 if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>() &&
4359 !shouldMapVisibilityToDLLExport(D))
4360 Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
4361
4362 if (LangOpts.OpenMP && !LangOpts.OpenMPSimd && D)
4363 getOpenMPRuntime().registerTargetGlobalVariable(D, Entry);
4364
4365 if (Entry->getValueType() == Ty && Entry->getAddressSpace() == TargetAS)
4366 return Entry;
4367
4368 // If there are two attempts to define the same mangled name, issue an
4369 // error.
4370 if (IsForDefinition && !Entry->isDeclaration()) {
4371 GlobalDecl OtherGD;
4372 const VarDecl *OtherD;
4373
4374 // Check that D is not yet in DiagnosedConflictingDefinitions is required
4375 // to make sure that we issue an error only once.
4376 if (D && lookupRepresentativeDecl(MangledName, OtherGD) &&
4377 (D->getCanonicalDecl() != OtherGD.getCanonicalDecl().getDecl()) &&
4378 (OtherD = dyn_cast<VarDecl>(OtherGD.getDecl())) &&
4379 OtherD->hasInit() &&
4380 DiagnosedConflictingDefinitions.insert(D).second) {
4381 getDiags().Report(D->getLocation(), diag::err_duplicate_mangled_name)
4382 << MangledName;
4383 getDiags().Report(OtherGD.getDecl()->getLocation(),
4384 diag::note_previous_definition);
4385 }
4386 }
4387
4388 // Make sure the result is of the correct type.
4389 if (Entry->getType()->getAddressSpace() != TargetAS) {
4390 return llvm::ConstantExpr::getAddrSpaceCast(Entry,
4391 Ty->getPointerTo(TargetAS));
4392 }
4393
4394 // (If global is requested for a definition, we always need to create a new
4395 // global, not just return a bitcast.)
4396 if (!IsForDefinition)
4397 return llvm::ConstantExpr::getBitCast(Entry, Ty->getPointerTo(TargetAS));
4398 }
4399
4400 auto DAddrSpace = GetGlobalVarAddressSpace(D);
4401
4402 auto *GV = new llvm::GlobalVariable(
4403 getModule(), Ty, false, llvm::GlobalValue::ExternalLinkage, nullptr,
4404 MangledName, nullptr, llvm::GlobalVariable::NotThreadLocal,
4405 getContext().getTargetAddressSpace(DAddrSpace));
4406
4407 // If we already created a global with the same mangled name (but different
4408 // type) before, take its name and remove it from its parent.
4409 if (Entry) {
4410 GV->takeName(Entry);
4411
4412 if (!Entry->use_empty()) {
4413 llvm::Constant *NewPtrForOldDecl =
4414 llvm::ConstantExpr::getBitCast(GV, Entry->getType());
4415 Entry->replaceAllUsesWith(NewPtrForOldDecl);
4416 }
4417
4418 Entry->eraseFromParent();
4419 }
4420
4421 // This is the first use or definition of a mangled name. If there is a
4422 // deferred decl with this name, remember that we need to emit it at the end
4423 // of the file.
4424 auto DDI = DeferredDecls.find(MangledName);
4425 if (DDI != DeferredDecls.end()) {
4426 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit
4427 // list, and remove it from DeferredDecls (since we don't need it anymore).
4428 addDeferredDeclToEmit(DDI->second);
4429 EmittedDeferredDecls[DDI->first] = DDI->second;
4430 DeferredDecls.erase(DDI);
4431 }
4432
4433 // Handle things which are present even on external declarations.
4434 if (D) {
4435 if (LangOpts.OpenMP && !LangOpts.OpenMPSimd)
4436 getOpenMPRuntime().registerTargetGlobalVariable(D, GV);
4437
4438 // FIXME: This code is overly simple and should be merged with other global
4439 // handling.
4440 GV->setConstant(isTypeConstant(D->getType(), false));
4441
4442 GV->setAlignment(getContext().getDeclAlign(D).getAsAlign());
4443
4444 setLinkageForGV(GV, D);
4445
4446 if (D->getTLSKind()) {
4447 if (D->getTLSKind() == VarDecl::TLS_Dynamic)
4448 CXXThreadLocals.push_back(D);
4449 setTLSMode(GV, *D);
4450 }
4451
4452 setGVProperties(GV, D);
4453
4454 // If required by the ABI, treat declarations of static data members with
4455 // inline initializers as definitions.
4456 if (getContext().isMSStaticDataMemberInlineDefinition(D)) {
4457 EmitGlobalVarDefinition(D);
4458 }
4459
4460 // Emit section information for extern variables.
4461 if (D->hasExternalStorage()) {
4462 if (const SectionAttr *SA = D->getAttr<SectionAttr>())
4463 GV->setSection(SA->getName());
4464 }
4465
4466 // Handle XCore specific ABI requirements.
4467 if (getTriple().getArch() == llvm::Triple::xcore &&
4468 D->getLanguageLinkage() == CLanguageLinkage &&
4469 D->getType().isConstant(Context) &&
4470 isExternallyVisible(D->getLinkageAndVisibility().getLinkage()))
4471 GV->setSection(".cp.rodata");
4472
4473 // Check if we a have a const declaration with an initializer, we may be
4474 // able to emit it as available_externally to expose it's value to the
4475 // optimizer.
4476 if (Context.getLangOpts().CPlusPlus && GV->hasExternalLinkage() &&
4477 D->getType().isConstQualified() && !GV->hasInitializer() &&
4478 !D->hasDefinition() && D->hasInit() && !D->hasAttr<DLLImportAttr>()) {
4479 const auto *Record =
4480 Context.getBaseElementType(D->getType())->getAsCXXRecordDecl();
4481 bool HasMutableFields = Record && Record->hasMutableFields();
4482 if (!HasMutableFields) {
4483 const VarDecl *InitDecl;
4484 const Expr *InitExpr = D->getAnyInitializer(InitDecl);
4485 if (InitExpr) {
4486 ConstantEmitter emitter(*this);
4487 llvm::Constant *Init = emitter.tryEmitForInitializer(*InitDecl);
4488 if (Init) {
4489 auto *InitType = Init->getType();
4490 if (GV->getValueType() != InitType) {
4491 // The type of the initializer does not match the definition.
4492 // This happens when an initializer has a different type from
4493 // the type of the global (because of padding at the end of a
4494 // structure for instance).
4495 GV->setName(StringRef());
4496 // Make a new global with the correct type, this is now guaranteed
4497 // to work.
4498 auto *NewGV = cast<llvm::GlobalVariable>(
4499 GetAddrOfGlobalVar(D, InitType, IsForDefinition)
4500 ->stripPointerCasts());
4501
4502 // Erase the old global, since it is no longer used.
4503 GV->eraseFromParent();
4504 GV = NewGV;
4505 } else {
4506 GV->setInitializer(Init);
4507 GV->setConstant(true);
4508 GV->setLinkage(llvm::GlobalValue::AvailableExternallyLinkage);
4509 }
4510 emitter.finalize(GV);
4511 }
4512 }
4513 }
4514 }
4515 }
4516
4517 if (GV->isDeclaration()) {
4518 getTargetCodeGenInfo().setTargetAttributes(D, GV, *this);
4519 // External HIP managed variables needed to be recorded for transformation
4520 // in both device and host compilations.
4521 if (getLangOpts().CUDA && D && D->hasAttr<HIPManagedAttr>() &&
4522 D->hasExternalStorage())
4523 getCUDARuntime().handleVarRegistration(D, *GV);
4524 }
4525
4526 if (D)
4527 SanitizerMD->reportGlobal(GV, *D);
4528
4529 LangAS ExpectedAS =
4530 D ? D->getType().getAddressSpace()
4531 : (LangOpts.OpenCL ? LangAS::opencl_global : LangAS::Default);
4532 assert(getContext().getTargetAddressSpace(ExpectedAS) == TargetAS);
4533 if (DAddrSpace != ExpectedAS) {
4534 return getTargetCodeGenInfo().performAddrSpaceCast(
4535 *this, GV, DAddrSpace, ExpectedAS, Ty->getPointerTo(TargetAS));
4536 }
4537
4538 return GV;
4539 }
4540
4541 llvm::Constant *
GetAddrOfGlobal(GlobalDecl GD,ForDefinition_t IsForDefinition)4542 CodeGenModule::GetAddrOfGlobal(GlobalDecl GD, ForDefinition_t IsForDefinition) {
4543 const Decl *D = GD.getDecl();
4544
4545 if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D))
4546 return getAddrOfCXXStructor(GD, /*FnInfo=*/nullptr, /*FnType=*/nullptr,
4547 /*DontDefer=*/false, IsForDefinition);
4548
4549 if (isa<CXXMethodDecl>(D)) {
4550 auto FInfo =
4551 &getTypes().arrangeCXXMethodDeclaration(cast<CXXMethodDecl>(D));
4552 auto Ty = getTypes().GetFunctionType(*FInfo);
4553 return GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer=*/false,
4554 IsForDefinition);
4555 }
4556
4557 if (isa<FunctionDecl>(D)) {
4558 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD);
4559 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI);
4560 return GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer=*/false,
4561 IsForDefinition);
4562 }
4563
4564 return GetAddrOfGlobalVar(cast<VarDecl>(D), /*Ty=*/nullptr, IsForDefinition);
4565 }
4566
CreateOrReplaceCXXRuntimeVariable(StringRef Name,llvm::Type * Ty,llvm::GlobalValue::LinkageTypes Linkage,llvm::Align Alignment)4567 llvm::GlobalVariable *CodeGenModule::CreateOrReplaceCXXRuntimeVariable(
4568 StringRef Name, llvm::Type *Ty, llvm::GlobalValue::LinkageTypes Linkage,
4569 llvm::Align Alignment) {
4570 llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name);
4571 llvm::GlobalVariable *OldGV = nullptr;
4572
4573 if (GV) {
4574 // Check if the variable has the right type.
4575 if (GV->getValueType() == Ty)
4576 return GV;
4577
4578 // Because C++ name mangling, the only way we can end up with an already
4579 // existing global with the same name is if it has been declared extern "C".
4580 assert(GV->isDeclaration() && "Declaration has wrong type!");
4581 OldGV = GV;
4582 }
4583
4584 // Create a new variable.
4585 GV = new llvm::GlobalVariable(getModule(), Ty, /*isConstant=*/true,
4586 Linkage, nullptr, Name);
4587
4588 if (OldGV) {
4589 // Replace occurrences of the old variable if needed.
4590 GV->takeName(OldGV);
4591
4592 if (!OldGV->use_empty()) {
4593 llvm::Constant *NewPtrForOldDecl =
4594 llvm::ConstantExpr::getBitCast(GV, OldGV->getType());
4595 OldGV->replaceAllUsesWith(NewPtrForOldDecl);
4596 }
4597
4598 OldGV->eraseFromParent();
4599 }
4600
4601 if (supportsCOMDAT() && GV->isWeakForLinker() &&
4602 !GV->hasAvailableExternallyLinkage())
4603 GV->setComdat(TheModule.getOrInsertComdat(GV->getName()));
4604
4605 GV->setAlignment(Alignment);
4606
4607 return GV;
4608 }
4609
4610 /// GetAddrOfGlobalVar - Return the llvm::Constant for the address of the
4611 /// given global variable. If Ty is non-null and if the global doesn't exist,
4612 /// then it will be created with the specified type instead of whatever the
4613 /// normal requested type would be. If IsForDefinition is true, it is guaranteed
4614 /// that an actual global with type Ty will be returned, not conversion of a
4615 /// variable with the same mangled name but some other type.
GetAddrOfGlobalVar(const VarDecl * D,llvm::Type * Ty,ForDefinition_t IsForDefinition)4616 llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D,
4617 llvm::Type *Ty,
4618 ForDefinition_t IsForDefinition) {
4619 assert(D->hasGlobalStorage() && "Not a global variable");
4620 QualType ASTTy = D->getType();
4621 if (!Ty)
4622 Ty = getTypes().ConvertTypeForMem(ASTTy);
4623
4624 StringRef MangledName = getMangledName(D);
4625 return GetOrCreateLLVMGlobal(MangledName, Ty, ASTTy.getAddressSpace(), D,
4626 IsForDefinition);
4627 }
4628
4629 /// CreateRuntimeVariable - Create a new runtime global variable with the
4630 /// specified type and name.
4631 llvm::Constant *
CreateRuntimeVariable(llvm::Type * Ty,StringRef Name)4632 CodeGenModule::CreateRuntimeVariable(llvm::Type *Ty,
4633 StringRef Name) {
4634 LangAS AddrSpace = getContext().getLangOpts().OpenCL ? LangAS::opencl_global
4635 : LangAS::Default;
4636 auto *Ret = GetOrCreateLLVMGlobal(Name, Ty, AddrSpace, nullptr);
4637 setDSOLocal(cast<llvm::GlobalValue>(Ret->stripPointerCasts()));
4638 return Ret;
4639 }
4640
EmitTentativeDefinition(const VarDecl * D)4641 void CodeGenModule::EmitTentativeDefinition(const VarDecl *D) {
4642 assert(!D->getInit() && "Cannot emit definite definitions here!");
4643
4644 StringRef MangledName = getMangledName(D);
4645 llvm::GlobalValue *GV = GetGlobalValue(MangledName);
4646
4647 // We already have a definition, not declaration, with the same mangled name.
4648 // Emitting of declaration is not required (and actually overwrites emitted
4649 // definition).
4650 if (GV && !GV->isDeclaration())
4651 return;
4652
4653 // If we have not seen a reference to this variable yet, place it into the
4654 // deferred declarations table to be emitted if needed later.
4655 if (!MustBeEmitted(D) && !GV) {
4656 DeferredDecls[MangledName] = D;
4657 return;
4658 }
4659
4660 // The tentative definition is the only definition.
4661 EmitGlobalVarDefinition(D);
4662 }
4663
EmitExternalDeclaration(const VarDecl * D)4664 void CodeGenModule::EmitExternalDeclaration(const VarDecl *D) {
4665 EmitExternalVarDeclaration(D);
4666 }
4667
GetTargetTypeStoreSize(llvm::Type * Ty) const4668 CharUnits CodeGenModule::GetTargetTypeStoreSize(llvm::Type *Ty) const {
4669 return Context.toCharUnitsFromBits(
4670 getDataLayout().getTypeStoreSizeInBits(Ty));
4671 }
4672
GetGlobalVarAddressSpace(const VarDecl * D)4673 LangAS CodeGenModule::GetGlobalVarAddressSpace(const VarDecl *D) {
4674 if (LangOpts.OpenCL) {
4675 LangAS AS = D ? D->getType().getAddressSpace() : LangAS::opencl_global;
4676 assert(AS == LangAS::opencl_global ||
4677 AS == LangAS::opencl_global_device ||
4678 AS == LangAS::opencl_global_host ||
4679 AS == LangAS::opencl_constant ||
4680 AS == LangAS::opencl_local ||
4681 AS >= LangAS::FirstTargetAddressSpace);
4682 return AS;
4683 }
4684
4685 if (LangOpts.SYCLIsDevice &&
4686 (!D || D->getType().getAddressSpace() == LangAS::Default))
4687 return LangAS::sycl_global;
4688
4689 if (LangOpts.CUDA && LangOpts.CUDAIsDevice) {
4690 if (D && D->hasAttr<CUDAConstantAttr>())
4691 return LangAS::cuda_constant;
4692 else if (D && D->hasAttr<CUDASharedAttr>())
4693 return LangAS::cuda_shared;
4694 else if (D && D->hasAttr<CUDADeviceAttr>())
4695 return LangAS::cuda_device;
4696 else if (D && D->getType().isConstQualified())
4697 return LangAS::cuda_constant;
4698 else
4699 return LangAS::cuda_device;
4700 }
4701
4702 if (LangOpts.OpenMP) {
4703 LangAS AS;
4704 if (OpenMPRuntime->hasAllocateAttributeForGlobalVar(D, AS))
4705 return AS;
4706 }
4707 return getTargetCodeGenInfo().getGlobalVarAddressSpace(*this, D);
4708 }
4709
GetGlobalConstantAddressSpace() const4710 LangAS CodeGenModule::GetGlobalConstantAddressSpace() const {
4711 // OpenCL v1.2 s6.5.3: a string literal is in the constant address space.
4712 if (LangOpts.OpenCL)
4713 return LangAS::opencl_constant;
4714 if (LangOpts.SYCLIsDevice)
4715 return LangAS::sycl_global;
4716 if (LangOpts.HIP && LangOpts.CUDAIsDevice && getTriple().isSPIRV())
4717 // For HIPSPV map literals to cuda_device (maps to CrossWorkGroup in SPIR-V)
4718 // instead of default AS (maps to Generic in SPIR-V). Otherwise, we end up
4719 // with OpVariable instructions with Generic storage class which is not
4720 // allowed (SPIR-V V1.6 s3.42.8). Also, mapping literals to SPIR-V
4721 // UniformConstant storage class is not viable as pointers to it may not be
4722 // casted to Generic pointers which are used to model HIP's "flat" pointers.
4723 return LangAS::cuda_device;
4724 if (auto AS = getTarget().getConstantAddressSpace())
4725 return *AS;
4726 return LangAS::Default;
4727 }
4728
4729 // In address space agnostic languages, string literals are in default address
4730 // space in AST. However, certain targets (e.g. amdgcn) request them to be
4731 // emitted in constant address space in LLVM IR. To be consistent with other
4732 // parts of AST, string literal global variables in constant address space
4733 // need to be casted to default address space before being put into address
4734 // map and referenced by other part of CodeGen.
4735 // In OpenCL, string literals are in constant address space in AST, therefore
4736 // they should not be casted to default address space.
4737 static llvm::Constant *
castStringLiteralToDefaultAddressSpace(CodeGenModule & CGM,llvm::GlobalVariable * GV)4738 castStringLiteralToDefaultAddressSpace(CodeGenModule &CGM,
4739 llvm::GlobalVariable *GV) {
4740 llvm::Constant *Cast = GV;
4741 if (!CGM.getLangOpts().OpenCL) {
4742 auto AS = CGM.GetGlobalConstantAddressSpace();
4743 if (AS != LangAS::Default)
4744 Cast = CGM.getTargetCodeGenInfo().performAddrSpaceCast(
4745 CGM, GV, AS, LangAS::Default,
4746 GV->getValueType()->getPointerTo(
4747 CGM.getContext().getTargetAddressSpace(LangAS::Default)));
4748 }
4749 return Cast;
4750 }
4751
4752 template<typename SomeDecl>
MaybeHandleStaticInExternC(const SomeDecl * D,llvm::GlobalValue * GV)4753 void CodeGenModule::MaybeHandleStaticInExternC(const SomeDecl *D,
4754 llvm::GlobalValue *GV) {
4755 if (!getLangOpts().CPlusPlus)
4756 return;
4757
4758 // Must have 'used' attribute, or else inline assembly can't rely on
4759 // the name existing.
4760 if (!D->template hasAttr<UsedAttr>())
4761 return;
4762
4763 // Must have internal linkage and an ordinary name.
4764 if (!D->getIdentifier() || D->getFormalLinkage() != InternalLinkage)
4765 return;
4766
4767 // Must be in an extern "C" context. Entities declared directly within
4768 // a record are not extern "C" even if the record is in such a context.
4769 const SomeDecl *First = D->getFirstDecl();
4770 if (First->getDeclContext()->isRecord() || !First->isInExternCContext())
4771 return;
4772
4773 // OK, this is an internal linkage entity inside an extern "C" linkage
4774 // specification. Make a note of that so we can give it the "expected"
4775 // mangled name if nothing else is using that name.
4776 std::pair<StaticExternCMap::iterator, bool> R =
4777 StaticExternCValues.insert(std::make_pair(D->getIdentifier(), GV));
4778
4779 // If we have multiple internal linkage entities with the same name
4780 // in extern "C" regions, none of them gets that name.
4781 if (!R.second)
4782 R.first->second = nullptr;
4783 }
4784
shouldBeInCOMDAT(CodeGenModule & CGM,const Decl & D)4785 static bool shouldBeInCOMDAT(CodeGenModule &CGM, const Decl &D) {
4786 if (!CGM.supportsCOMDAT())
4787 return false;
4788
4789 if (D.hasAttr<SelectAnyAttr>())
4790 return true;
4791
4792 GVALinkage Linkage;
4793 if (auto *VD = dyn_cast<VarDecl>(&D))
4794 Linkage = CGM.getContext().GetGVALinkageForVariable(VD);
4795 else
4796 Linkage = CGM.getContext().GetGVALinkageForFunction(cast<FunctionDecl>(&D));
4797
4798 switch (Linkage) {
4799 case GVA_Internal:
4800 case GVA_AvailableExternally:
4801 case GVA_StrongExternal:
4802 return false;
4803 case GVA_DiscardableODR:
4804 case GVA_StrongODR:
4805 return true;
4806 }
4807 llvm_unreachable("No such linkage");
4808 }
4809
maybeSetTrivialComdat(const Decl & D,llvm::GlobalObject & GO)4810 void CodeGenModule::maybeSetTrivialComdat(const Decl &D,
4811 llvm::GlobalObject &GO) {
4812 if (!shouldBeInCOMDAT(*this, D))
4813 return;
4814 GO.setComdat(TheModule.getOrInsertComdat(GO.getName()));
4815 }
4816
4817 /// Pass IsTentative as true if you want to create a tentative definition.
EmitGlobalVarDefinition(const VarDecl * D,bool IsTentative)4818 void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D,
4819 bool IsTentative) {
4820 // OpenCL global variables of sampler type are translated to function calls,
4821 // therefore no need to be translated.
4822 QualType ASTTy = D->getType();
4823 if (getLangOpts().OpenCL && ASTTy->isSamplerT())
4824 return;
4825
4826 // If this is OpenMP device, check if it is legal to emit this global
4827 // normally.
4828 if (LangOpts.OpenMPIsDevice && OpenMPRuntime &&
4829 OpenMPRuntime->emitTargetGlobalVariable(D))
4830 return;
4831
4832 llvm::TrackingVH<llvm::Constant> Init;
4833 bool NeedsGlobalCtor = false;
4834 // Whether the definition of the variable is available externally.
4835 // If yes, we shouldn't emit the GloablCtor and GlobalDtor for the variable
4836 // since this is the job for its original source.
4837 bool IsDefinitionAvailableExternally =
4838 getContext().GetGVALinkageForVariable(D) == GVA_AvailableExternally;
4839 bool NeedsGlobalDtor =
4840 !IsDefinitionAvailableExternally &&
4841 D->needsDestruction(getContext()) == QualType::DK_cxx_destructor;
4842
4843 const VarDecl *InitDecl;
4844 const Expr *InitExpr = D->getAnyInitializer(InitDecl);
4845
4846 std::optional<ConstantEmitter> emitter;
4847
4848 // CUDA E.2.4.1 "__shared__ variables cannot have an initialization
4849 // as part of their declaration." Sema has already checked for
4850 // error cases, so we just need to set Init to UndefValue.
4851 bool IsCUDASharedVar =
4852 getLangOpts().CUDAIsDevice && D->hasAttr<CUDASharedAttr>();
4853 // Shadows of initialized device-side global variables are also left
4854 // undefined.
4855 // Managed Variables should be initialized on both host side and device side.
4856 bool IsCUDAShadowVar =
4857 !getLangOpts().CUDAIsDevice && !D->hasAttr<HIPManagedAttr>() &&
4858 (D->hasAttr<CUDAConstantAttr>() || D->hasAttr<CUDADeviceAttr>() ||
4859 D->hasAttr<CUDASharedAttr>());
4860 bool IsCUDADeviceShadowVar =
4861 getLangOpts().CUDAIsDevice && !D->hasAttr<HIPManagedAttr>() &&
4862 (D->getType()->isCUDADeviceBuiltinSurfaceType() ||
4863 D->getType()->isCUDADeviceBuiltinTextureType());
4864 if (getLangOpts().CUDA &&
4865 (IsCUDASharedVar || IsCUDAShadowVar || IsCUDADeviceShadowVar))
4866 Init = llvm::UndefValue::get(getTypes().ConvertTypeForMem(ASTTy));
4867 else if (D->hasAttr<LoaderUninitializedAttr>())
4868 Init = llvm::UndefValue::get(getTypes().ConvertTypeForMem(ASTTy));
4869 else if (!InitExpr) {
4870 // This is a tentative definition; tentative definitions are
4871 // implicitly initialized with { 0 }.
4872 //
4873 // Note that tentative definitions are only emitted at the end of
4874 // a translation unit, so they should never have incomplete
4875 // type. In addition, EmitTentativeDefinition makes sure that we
4876 // never attempt to emit a tentative definition if a real one
4877 // exists. A use may still exists, however, so we still may need
4878 // to do a RAUW.
4879 assert(!ASTTy->isIncompleteType() && "Unexpected incomplete type");
4880 Init = EmitNullConstant(D->getType());
4881 } else {
4882 initializedGlobalDecl = GlobalDecl(D);
4883 emitter.emplace(*this);
4884 llvm::Constant *Initializer = emitter->tryEmitForInitializer(*InitDecl);
4885 if (!Initializer) {
4886 QualType T = InitExpr->getType();
4887 if (D->getType()->isReferenceType())
4888 T = D->getType();
4889
4890 if (getLangOpts().CPlusPlus) {
4891 if (InitDecl->hasFlexibleArrayInit(getContext()))
4892 ErrorUnsupported(D, "flexible array initializer");
4893 Init = EmitNullConstant(T);
4894
4895 if (!IsDefinitionAvailableExternally)
4896 NeedsGlobalCtor = true;
4897 } else {
4898 ErrorUnsupported(D, "static initializer");
4899 Init = llvm::UndefValue::get(getTypes().ConvertType(T));
4900 }
4901 } else {
4902 Init = Initializer;
4903 // We don't need an initializer, so remove the entry for the delayed
4904 // initializer position (just in case this entry was delayed) if we
4905 // also don't need to register a destructor.
4906 if (getLangOpts().CPlusPlus && !NeedsGlobalDtor)
4907 DelayedCXXInitPosition.erase(D);
4908
4909 #ifndef NDEBUG
4910 CharUnits VarSize = getContext().getTypeSizeInChars(ASTTy) +
4911 InitDecl->getFlexibleArrayInitChars(getContext());
4912 CharUnits CstSize = CharUnits::fromQuantity(
4913 getDataLayout().getTypeAllocSize(Init->getType()));
4914 assert(VarSize == CstSize && "Emitted constant has unexpected size");
4915 #endif
4916 }
4917 }
4918
4919 llvm::Type* InitType = Init->getType();
4920 llvm::Constant *Entry =
4921 GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative));
4922
4923 // Strip off pointer casts if we got them.
4924 Entry = Entry->stripPointerCasts();
4925
4926 // Entry is now either a Function or GlobalVariable.
4927 auto *GV = dyn_cast<llvm::GlobalVariable>(Entry);
4928
4929 // We have a definition after a declaration with the wrong type.
4930 // We must make a new GlobalVariable* and update everything that used OldGV
4931 // (a declaration or tentative definition) with the new GlobalVariable*
4932 // (which will be a definition).
4933 //
4934 // This happens if there is a prototype for a global (e.g.
4935 // "extern int x[];") and then a definition of a different type (e.g.
4936 // "int x[10];"). This also happens when an initializer has a different type
4937 // from the type of the global (this happens with unions).
4938 if (!GV || GV->getValueType() != InitType ||
4939 GV->getType()->getAddressSpace() !=
4940 getContext().getTargetAddressSpace(GetGlobalVarAddressSpace(D))) {
4941
4942 // Move the old entry aside so that we'll create a new one.
4943 Entry->setName(StringRef());
4944
4945 // Make a new global with the correct type, this is now guaranteed to work.
4946 GV = cast<llvm::GlobalVariable>(
4947 GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative))
4948 ->stripPointerCasts());
4949
4950 // Replace all uses of the old global with the new global
4951 llvm::Constant *NewPtrForOldDecl =
4952 llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV,
4953 Entry->getType());
4954 Entry->replaceAllUsesWith(NewPtrForOldDecl);
4955
4956 // Erase the old global, since it is no longer used.
4957 cast<llvm::GlobalValue>(Entry)->eraseFromParent();
4958 }
4959
4960 MaybeHandleStaticInExternC(D, GV);
4961
4962 if (D->hasAttr<AnnotateAttr>())
4963 AddGlobalAnnotations(D, GV);
4964
4965 // Set the llvm linkage type as appropriate.
4966 llvm::GlobalValue::LinkageTypes Linkage =
4967 getLLVMLinkageVarDefinition(D, GV->isConstant());
4968
4969 // CUDA B.2.1 "The __device__ qualifier declares a variable that resides on
4970 // the device. [...]"
4971 // CUDA B.2.2 "The __constant__ qualifier, optionally used together with
4972 // __device__, declares a variable that: [...]
4973 // Is accessible from all the threads within the grid and from the host
4974 // through the runtime library (cudaGetSymbolAddress() / cudaGetSymbolSize()
4975 // / cudaMemcpyToSymbol() / cudaMemcpyFromSymbol())."
4976 if (GV && LangOpts.CUDA) {
4977 if (LangOpts.CUDAIsDevice) {
4978 if (Linkage != llvm::GlobalValue::InternalLinkage &&
4979 (D->hasAttr<CUDADeviceAttr>() || D->hasAttr<CUDAConstantAttr>() ||
4980 D->getType()->isCUDADeviceBuiltinSurfaceType() ||
4981 D->getType()->isCUDADeviceBuiltinTextureType()))
4982 GV->setExternallyInitialized(true);
4983 } else {
4984 getCUDARuntime().internalizeDeviceSideVar(D, Linkage);
4985 }
4986 getCUDARuntime().handleVarRegistration(D, *GV);
4987 }
4988
4989 GV->setInitializer(Init);
4990 if (emitter)
4991 emitter->finalize(GV);
4992
4993 // If it is safe to mark the global 'constant', do so now.
4994 GV->setConstant(!NeedsGlobalCtor && !NeedsGlobalDtor &&
4995 isTypeConstant(D->getType(), true));
4996
4997 // If it is in a read-only section, mark it 'constant'.
4998 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) {
4999 const ASTContext::SectionInfo &SI = Context.SectionInfos[SA->getName()];
5000 if ((SI.SectionFlags & ASTContext::PSF_Write) == 0)
5001 GV->setConstant(true);
5002 }
5003
5004 CharUnits AlignVal = getContext().getDeclAlign(D);
5005 // Check for alignment specifed in an 'omp allocate' directive.
5006 if (std::optional<CharUnits> AlignValFromAllocate =
5007 getOMPAllocateAlignment(D))
5008 AlignVal = *AlignValFromAllocate;
5009 GV->setAlignment(AlignVal.getAsAlign());
5010
5011 // On Darwin, unlike other Itanium C++ ABI platforms, the thread-wrapper
5012 // function is only defined alongside the variable, not also alongside
5013 // callers. Normally, all accesses to a thread_local go through the
5014 // thread-wrapper in order to ensure initialization has occurred, underlying
5015 // variable will never be used other than the thread-wrapper, so it can be
5016 // converted to internal linkage.
5017 //
5018 // However, if the variable has the 'constinit' attribute, it _can_ be
5019 // referenced directly, without calling the thread-wrapper, so the linkage
5020 // must not be changed.
5021 //
5022 // Additionally, if the variable isn't plain external linkage, e.g. if it's
5023 // weak or linkonce, the de-duplication semantics are important to preserve,
5024 // so we don't change the linkage.
5025 if (D->getTLSKind() == VarDecl::TLS_Dynamic &&
5026 Linkage == llvm::GlobalValue::ExternalLinkage &&
5027 Context.getTargetInfo().getTriple().isOSDarwin() &&
5028 !D->hasAttr<ConstInitAttr>())
5029 Linkage = llvm::GlobalValue::InternalLinkage;
5030
5031 GV->setLinkage(Linkage);
5032 if (D->hasAttr<DLLImportAttr>())
5033 GV->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass);
5034 else if (D->hasAttr<DLLExportAttr>())
5035 GV->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass);
5036 else
5037 GV->setDLLStorageClass(llvm::GlobalVariable::DefaultStorageClass);
5038
5039 if (Linkage == llvm::GlobalVariable::CommonLinkage) {
5040 // common vars aren't constant even if declared const.
5041 GV->setConstant(false);
5042 // Tentative definition of global variables may be initialized with
5043 // non-zero null pointers. In this case they should have weak linkage
5044 // since common linkage must have zero initializer and must not have
5045 // explicit section therefore cannot have non-zero initial value.
5046 if (!GV->getInitializer()->isNullValue())
5047 GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage);
5048 }
5049
5050 setNonAliasAttributes(D, GV);
5051
5052 if (D->getTLSKind() && !GV->isThreadLocal()) {
5053 if (D->getTLSKind() == VarDecl::TLS_Dynamic)
5054 CXXThreadLocals.push_back(D);
5055 setTLSMode(GV, *D);
5056 }
5057
5058 maybeSetTrivialComdat(*D, *GV);
5059
5060 // Emit the initializer function if necessary.
5061 if (NeedsGlobalCtor || NeedsGlobalDtor)
5062 EmitCXXGlobalVarDeclInitFunc(D, GV, NeedsGlobalCtor);
5063
5064 SanitizerMD->reportGlobal(GV, *D, NeedsGlobalCtor);
5065
5066 // Emit global variable debug information.
5067 if (CGDebugInfo *DI = getModuleDebugInfo())
5068 if (getCodeGenOpts().hasReducedDebugInfo())
5069 DI->EmitGlobalVariable(GV, D);
5070 }
5071
EmitExternalVarDeclaration(const VarDecl * D)5072 void CodeGenModule::EmitExternalVarDeclaration(const VarDecl *D) {
5073 if (CGDebugInfo *DI = getModuleDebugInfo())
5074 if (getCodeGenOpts().hasReducedDebugInfo()) {
5075 QualType ASTTy = D->getType();
5076 llvm::Type *Ty = getTypes().ConvertTypeForMem(D->getType());
5077 llvm::Constant *GV =
5078 GetOrCreateLLVMGlobal(D->getName(), Ty, ASTTy.getAddressSpace(), D);
5079 DI->EmitExternalVariable(
5080 cast<llvm::GlobalVariable>(GV->stripPointerCasts()), D);
5081 }
5082 }
5083
isVarDeclStrongDefinition(const ASTContext & Context,CodeGenModule & CGM,const VarDecl * D,bool NoCommon)5084 static bool isVarDeclStrongDefinition(const ASTContext &Context,
5085 CodeGenModule &CGM, const VarDecl *D,
5086 bool NoCommon) {
5087 // Don't give variables common linkage if -fno-common was specified unless it
5088 // was overridden by a NoCommon attribute.
5089 if ((NoCommon || D->hasAttr<NoCommonAttr>()) && !D->hasAttr<CommonAttr>())
5090 return true;
5091
5092 // C11 6.9.2/2:
5093 // A declaration of an identifier for an object that has file scope without
5094 // an initializer, and without a storage-class specifier or with the
5095 // storage-class specifier static, constitutes a tentative definition.
5096 if (D->getInit() || D->hasExternalStorage())
5097 return true;
5098
5099 // A variable cannot be both common and exist in a section.
5100 if (D->hasAttr<SectionAttr>())
5101 return true;
5102
5103 // A variable cannot be both common and exist in a section.
5104 // We don't try to determine which is the right section in the front-end.
5105 // If no specialized section name is applicable, it will resort to default.
5106 if (D->hasAttr<PragmaClangBSSSectionAttr>() ||
5107 D->hasAttr<PragmaClangDataSectionAttr>() ||
5108 D->hasAttr<PragmaClangRelroSectionAttr>() ||
5109 D->hasAttr<PragmaClangRodataSectionAttr>())
5110 return true;
5111
5112 // Thread local vars aren't considered common linkage.
5113 if (D->getTLSKind())
5114 return true;
5115
5116 // Tentative definitions marked with WeakImportAttr are true definitions.
5117 if (D->hasAttr<WeakImportAttr>())
5118 return true;
5119
5120 // A variable cannot be both common and exist in a comdat.
5121 if (shouldBeInCOMDAT(CGM, *D))
5122 return true;
5123
5124 // Declarations with a required alignment do not have common linkage in MSVC
5125 // mode.
5126 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
5127 if (D->hasAttr<AlignedAttr>())
5128 return true;
5129 QualType VarType = D->getType();
5130 if (Context.isAlignmentRequired(VarType))
5131 return true;
5132
5133 if (const auto *RT = VarType->getAs<RecordType>()) {
5134 const RecordDecl *RD = RT->getDecl();
5135 for (const FieldDecl *FD : RD->fields()) {
5136 if (FD->isBitField())
5137 continue;
5138 if (FD->hasAttr<AlignedAttr>())
5139 return true;
5140 if (Context.isAlignmentRequired(FD->getType()))
5141 return true;
5142 }
5143 }
5144 }
5145
5146 // Microsoft's link.exe doesn't support alignments greater than 32 bytes for
5147 // common symbols, so symbols with greater alignment requirements cannot be
5148 // common.
5149 // Other COFF linkers (ld.bfd and LLD) support arbitrary power-of-two
5150 // alignments for common symbols via the aligncomm directive, so this
5151 // restriction only applies to MSVC environments.
5152 if (Context.getTargetInfo().getTriple().isKnownWindowsMSVCEnvironment() &&
5153 Context.getTypeAlignIfKnown(D->getType()) >
5154 Context.toBits(CharUnits::fromQuantity(32)))
5155 return true;
5156
5157 return false;
5158 }
5159
getLLVMLinkageForDeclarator(const DeclaratorDecl * D,GVALinkage Linkage,bool IsConstantVariable)5160 llvm::GlobalValue::LinkageTypes CodeGenModule::getLLVMLinkageForDeclarator(
5161 const DeclaratorDecl *D, GVALinkage Linkage, bool IsConstantVariable) {
5162 if (Linkage == GVA_Internal)
5163 return llvm::Function::InternalLinkage;
5164
5165 if (D->hasAttr<WeakAttr>())
5166 return llvm::GlobalVariable::WeakAnyLinkage;
5167
5168 if (const auto *FD = D->getAsFunction())
5169 if (FD->isMultiVersion() && Linkage == GVA_AvailableExternally)
5170 return llvm::GlobalVariable::LinkOnceAnyLinkage;
5171
5172 // We are guaranteed to have a strong definition somewhere else,
5173 // so we can use available_externally linkage.
5174 if (Linkage == GVA_AvailableExternally)
5175 return llvm::GlobalValue::AvailableExternallyLinkage;
5176
5177 // Note that Apple's kernel linker doesn't support symbol
5178 // coalescing, so we need to avoid linkonce and weak linkages there.
5179 // Normally, this means we just map to internal, but for explicit
5180 // instantiations we'll map to external.
5181
5182 // In C++, the compiler has to emit a definition in every translation unit
5183 // that references the function. We should use linkonce_odr because
5184 // a) if all references in this translation unit are optimized away, we
5185 // don't need to codegen it. b) if the function persists, it needs to be
5186 // merged with other definitions. c) C++ has the ODR, so we know the
5187 // definition is dependable.
5188 if (Linkage == GVA_DiscardableODR)
5189 return !Context.getLangOpts().AppleKext ? llvm::Function::LinkOnceODRLinkage
5190 : llvm::Function::InternalLinkage;
5191
5192 // An explicit instantiation of a template has weak linkage, since
5193 // explicit instantiations can occur in multiple translation units
5194 // and must all be equivalent. However, we are not allowed to
5195 // throw away these explicit instantiations.
5196 //
5197 // CUDA/HIP: For -fno-gpu-rdc case, device code is limited to one TU,
5198 // so say that CUDA templates are either external (for kernels) or internal.
5199 // This lets llvm perform aggressive inter-procedural optimizations. For
5200 // -fgpu-rdc case, device function calls across multiple TU's are allowed,
5201 // therefore we need to follow the normal linkage paradigm.
5202 if (Linkage == GVA_StrongODR) {
5203 if (getLangOpts().AppleKext)
5204 return llvm::Function::ExternalLinkage;
5205 if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice &&
5206 !getLangOpts().GPURelocatableDeviceCode)
5207 return D->hasAttr<CUDAGlobalAttr>() ? llvm::Function::ExternalLinkage
5208 : llvm::Function::InternalLinkage;
5209 return llvm::Function::WeakODRLinkage;
5210 }
5211
5212 // C++ doesn't have tentative definitions and thus cannot have common
5213 // linkage.
5214 if (!getLangOpts().CPlusPlus && isa<VarDecl>(D) &&
5215 !isVarDeclStrongDefinition(Context, *this, cast<VarDecl>(D),
5216 CodeGenOpts.NoCommon))
5217 return llvm::GlobalVariable::CommonLinkage;
5218
5219 // selectany symbols are externally visible, so use weak instead of
5220 // linkonce. MSVC optimizes away references to const selectany globals, so
5221 // all definitions should be the same and ODR linkage should be used.
5222 // http://msdn.microsoft.com/en-us/library/5tkz6s71.aspx
5223 if (D->hasAttr<SelectAnyAttr>())
5224 return llvm::GlobalVariable::WeakODRLinkage;
5225
5226 // Otherwise, we have strong external linkage.
5227 assert(Linkage == GVA_StrongExternal);
5228 return llvm::GlobalVariable::ExternalLinkage;
5229 }
5230
getLLVMLinkageVarDefinition(const VarDecl * VD,bool IsConstant)5231 llvm::GlobalValue::LinkageTypes CodeGenModule::getLLVMLinkageVarDefinition(
5232 const VarDecl *VD, bool IsConstant) {
5233 GVALinkage Linkage = getContext().GetGVALinkageForVariable(VD);
5234 return getLLVMLinkageForDeclarator(VD, Linkage, IsConstant);
5235 }
5236
5237 /// Replace the uses of a function that was declared with a non-proto type.
5238 /// We want to silently drop extra arguments from call sites
replaceUsesOfNonProtoConstant(llvm::Constant * old,llvm::Function * newFn)5239 static void replaceUsesOfNonProtoConstant(llvm::Constant *old,
5240 llvm::Function *newFn) {
5241 // Fast path.
5242 if (old->use_empty()) return;
5243
5244 llvm::Type *newRetTy = newFn->getReturnType();
5245 SmallVector<llvm::Value*, 4> newArgs;
5246
5247 for (llvm::Value::use_iterator ui = old->use_begin(), ue = old->use_end();
5248 ui != ue; ) {
5249 llvm::Value::use_iterator use = ui++; // Increment before the use is erased.
5250 llvm::User *user = use->getUser();
5251
5252 // Recognize and replace uses of bitcasts. Most calls to
5253 // unprototyped functions will use bitcasts.
5254 if (auto *bitcast = dyn_cast<llvm::ConstantExpr>(user)) {
5255 if (bitcast->getOpcode() == llvm::Instruction::BitCast)
5256 replaceUsesOfNonProtoConstant(bitcast, newFn);
5257 continue;
5258 }
5259
5260 // Recognize calls to the function.
5261 llvm::CallBase *callSite = dyn_cast<llvm::CallBase>(user);
5262 if (!callSite) continue;
5263 if (!callSite->isCallee(&*use))
5264 continue;
5265
5266 // If the return types don't match exactly, then we can't
5267 // transform this call unless it's dead.
5268 if (callSite->getType() != newRetTy && !callSite->use_empty())
5269 continue;
5270
5271 // Get the call site's attribute list.
5272 SmallVector<llvm::AttributeSet, 8> newArgAttrs;
5273 llvm::AttributeList oldAttrs = callSite->getAttributes();
5274
5275 // If the function was passed too few arguments, don't transform.
5276 unsigned newNumArgs = newFn->arg_size();
5277 if (callSite->arg_size() < newNumArgs)
5278 continue;
5279
5280 // If extra arguments were passed, we silently drop them.
5281 // If any of the types mismatch, we don't transform.
5282 unsigned argNo = 0;
5283 bool dontTransform = false;
5284 for (llvm::Argument &A : newFn->args()) {
5285 if (callSite->getArgOperand(argNo)->getType() != A.getType()) {
5286 dontTransform = true;
5287 break;
5288 }
5289
5290 // Add any parameter attributes.
5291 newArgAttrs.push_back(oldAttrs.getParamAttrs(argNo));
5292 argNo++;
5293 }
5294 if (dontTransform)
5295 continue;
5296
5297 // Okay, we can transform this. Create the new call instruction and copy
5298 // over the required information.
5299 newArgs.append(callSite->arg_begin(), callSite->arg_begin() + argNo);
5300
5301 // Copy over any operand bundles.
5302 SmallVector<llvm::OperandBundleDef, 1> newBundles;
5303 callSite->getOperandBundlesAsDefs(newBundles);
5304
5305 llvm::CallBase *newCall;
5306 if (isa<llvm::CallInst>(callSite)) {
5307 newCall =
5308 llvm::CallInst::Create(newFn, newArgs, newBundles, "", callSite);
5309 } else {
5310 auto *oldInvoke = cast<llvm::InvokeInst>(callSite);
5311 newCall = llvm::InvokeInst::Create(newFn, oldInvoke->getNormalDest(),
5312 oldInvoke->getUnwindDest(), newArgs,
5313 newBundles, "", callSite);
5314 }
5315 newArgs.clear(); // for the next iteration
5316
5317 if (!newCall->getType()->isVoidTy())
5318 newCall->takeName(callSite);
5319 newCall->setAttributes(
5320 llvm::AttributeList::get(newFn->getContext(), oldAttrs.getFnAttrs(),
5321 oldAttrs.getRetAttrs(), newArgAttrs));
5322 newCall->setCallingConv(callSite->getCallingConv());
5323
5324 // Finally, remove the old call, replacing any uses with the new one.
5325 if (!callSite->use_empty())
5326 callSite->replaceAllUsesWith(newCall);
5327
5328 // Copy debug location attached to CI.
5329 if (callSite->getDebugLoc())
5330 newCall->setDebugLoc(callSite->getDebugLoc());
5331
5332 callSite->eraseFromParent();
5333 }
5334 }
5335
5336 /// ReplaceUsesOfNonProtoTypeWithRealFunction - This function is called when we
5337 /// implement a function with no prototype, e.g. "int foo() {}". If there are
5338 /// existing call uses of the old function in the module, this adjusts them to
5339 /// call the new function directly.
5340 ///
5341 /// This is not just a cleanup: the always_inline pass requires direct calls to
5342 /// functions to be able to inline them. If there is a bitcast in the way, it
5343 /// won't inline them. Instcombine normally deletes these calls, but it isn't
5344 /// run at -O0.
ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue * Old,llvm::Function * NewFn)5345 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old,
5346 llvm::Function *NewFn) {
5347 // If we're redefining a global as a function, don't transform it.
5348 if (!isa<llvm::Function>(Old)) return;
5349
5350 replaceUsesOfNonProtoConstant(Old, NewFn);
5351 }
5352
HandleCXXStaticMemberVarInstantiation(VarDecl * VD)5353 void CodeGenModule::HandleCXXStaticMemberVarInstantiation(VarDecl *VD) {
5354 auto DK = VD->isThisDeclarationADefinition();
5355 if (DK == VarDecl::Definition && VD->hasAttr<DLLImportAttr>())
5356 return;
5357
5358 TemplateSpecializationKind TSK = VD->getTemplateSpecializationKind();
5359 // If we have a definition, this might be a deferred decl. If the
5360 // instantiation is explicit, make sure we emit it at the end.
5361 if (VD->getDefinition() && TSK == TSK_ExplicitInstantiationDefinition)
5362 GetAddrOfGlobalVar(VD);
5363
5364 EmitTopLevelDecl(VD);
5365 }
5366
EmitGlobalFunctionDefinition(GlobalDecl GD,llvm::GlobalValue * GV)5367 void CodeGenModule::EmitGlobalFunctionDefinition(GlobalDecl GD,
5368 llvm::GlobalValue *GV) {
5369 const auto *D = cast<FunctionDecl>(GD.getDecl());
5370
5371 // Compute the function info and LLVM type.
5372 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD);
5373 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI);
5374
5375 // Get or create the prototype for the function.
5376 if (!GV || (GV->getValueType() != Ty))
5377 GV = cast<llvm::GlobalValue>(GetAddrOfFunction(GD, Ty, /*ForVTable=*/false,
5378 /*DontDefer=*/true,
5379 ForDefinition));
5380
5381 // Already emitted.
5382 if (!GV->isDeclaration())
5383 return;
5384
5385 // We need to set linkage and visibility on the function before
5386 // generating code for it because various parts of IR generation
5387 // want to propagate this information down (e.g. to local static
5388 // declarations).
5389 auto *Fn = cast<llvm::Function>(GV);
5390 setFunctionLinkage(GD, Fn);
5391
5392 // FIXME: this is redundant with part of setFunctionDefinitionAttributes
5393 setGVProperties(Fn, GD);
5394
5395 MaybeHandleStaticInExternC(D, Fn);
5396
5397 maybeSetTrivialComdat(*D, *Fn);
5398
5399 // Set CodeGen attributes that represent floating point environment.
5400 setLLVMFunctionFEnvAttributes(D, Fn);
5401
5402 CodeGenFunction(*this).GenerateCode(GD, Fn, FI);
5403
5404 setNonAliasAttributes(GD, Fn);
5405 SetLLVMFunctionAttributesForDefinition(D, Fn);
5406
5407 if (const ConstructorAttr *CA = D->getAttr<ConstructorAttr>())
5408 AddGlobalCtor(Fn, CA->getPriority());
5409 if (const DestructorAttr *DA = D->getAttr<DestructorAttr>())
5410 AddGlobalDtor(Fn, DA->getPriority(), true);
5411 if (D->hasAttr<AnnotateAttr>())
5412 AddGlobalAnnotations(D, Fn);
5413 }
5414
EmitAliasDefinition(GlobalDecl GD)5415 void CodeGenModule::EmitAliasDefinition(GlobalDecl GD) {
5416 const auto *D = cast<ValueDecl>(GD.getDecl());
5417 const AliasAttr *AA = D->getAttr<AliasAttr>();
5418 assert(AA && "Not an alias?");
5419
5420 StringRef MangledName = getMangledName(GD);
5421
5422 if (AA->getAliasee() == MangledName) {
5423 Diags.Report(AA->getLocation(), diag::err_cyclic_alias) << 0;
5424 return;
5425 }
5426
5427 // If there is a definition in the module, then it wins over the alias.
5428 // This is dubious, but allow it to be safe. Just ignore the alias.
5429 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
5430 if (Entry && !Entry->isDeclaration())
5431 return;
5432
5433 Aliases.push_back(GD);
5434
5435 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType());
5436
5437 // Create a reference to the named value. This ensures that it is emitted
5438 // if a deferred decl.
5439 llvm::Constant *Aliasee;
5440 llvm::GlobalValue::LinkageTypes LT;
5441 if (isa<llvm::FunctionType>(DeclTy)) {
5442 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, GD,
5443 /*ForVTable=*/false);
5444 LT = getFunctionLinkage(GD);
5445 } else {
5446 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), DeclTy, LangAS::Default,
5447 /*D=*/nullptr);
5448 if (const auto *VD = dyn_cast<VarDecl>(GD.getDecl()))
5449 LT = getLLVMLinkageVarDefinition(VD, D->getType().isConstQualified());
5450 else
5451 LT = getFunctionLinkage(GD);
5452 }
5453
5454 // Create the new alias itself, but don't set a name yet.
5455 unsigned AS = Aliasee->getType()->getPointerAddressSpace();
5456 auto *GA =
5457 llvm::GlobalAlias::create(DeclTy, AS, LT, "", Aliasee, &getModule());
5458
5459 if (Entry) {
5460 if (GA->getAliasee() == Entry) {
5461 Diags.Report(AA->getLocation(), diag::err_cyclic_alias) << 0;
5462 return;
5463 }
5464
5465 assert(Entry->isDeclaration());
5466
5467 // If there is a declaration in the module, then we had an extern followed
5468 // by the alias, as in:
5469 // extern int test6();
5470 // ...
5471 // int test6() __attribute__((alias("test7")));
5472 //
5473 // Remove it and replace uses of it with the alias.
5474 GA->takeName(Entry);
5475
5476 Entry->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GA,
5477 Entry->getType()));
5478 Entry->eraseFromParent();
5479 } else {
5480 GA->setName(MangledName);
5481 }
5482
5483 // Set attributes which are particular to an alias; this is a
5484 // specialization of the attributes which may be set on a global
5485 // variable/function.
5486 if (D->hasAttr<WeakAttr>() || D->hasAttr<WeakRefAttr>() ||
5487 D->isWeakImported()) {
5488 GA->setLinkage(llvm::Function::WeakAnyLinkage);
5489 }
5490
5491 if (const auto *VD = dyn_cast<VarDecl>(D))
5492 if (VD->getTLSKind())
5493 setTLSMode(GA, *VD);
5494
5495 SetCommonAttributes(GD, GA);
5496
5497 // Emit global alias debug information.
5498 if (isa<VarDecl>(D))
5499 if (CGDebugInfo *DI = getModuleDebugInfo())
5500 DI->EmitGlobalAlias(cast<llvm::GlobalValue>(GA->getAliasee()->stripPointerCasts()), GD);
5501 }
5502
emitIFuncDefinition(GlobalDecl GD)5503 void CodeGenModule::emitIFuncDefinition(GlobalDecl GD) {
5504 const auto *D = cast<ValueDecl>(GD.getDecl());
5505 const IFuncAttr *IFA = D->getAttr<IFuncAttr>();
5506 assert(IFA && "Not an ifunc?");
5507
5508 StringRef MangledName = getMangledName(GD);
5509
5510 if (IFA->getResolver() == MangledName) {
5511 Diags.Report(IFA->getLocation(), diag::err_cyclic_alias) << 1;
5512 return;
5513 }
5514
5515 // Report an error if some definition overrides ifunc.
5516 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
5517 if (Entry && !Entry->isDeclaration()) {
5518 GlobalDecl OtherGD;
5519 if (lookupRepresentativeDecl(MangledName, OtherGD) &&
5520 DiagnosedConflictingDefinitions.insert(GD).second) {
5521 Diags.Report(D->getLocation(), diag::err_duplicate_mangled_name)
5522 << MangledName;
5523 Diags.Report(OtherGD.getDecl()->getLocation(),
5524 diag::note_previous_definition);
5525 }
5526 return;
5527 }
5528
5529 Aliases.push_back(GD);
5530
5531 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType());
5532 llvm::Type *ResolverTy = llvm::GlobalIFunc::getResolverFunctionType(DeclTy);
5533 llvm::Constant *Resolver =
5534 GetOrCreateLLVMFunction(IFA->getResolver(), ResolverTy, {},
5535 /*ForVTable=*/false);
5536 llvm::GlobalIFunc *GIF =
5537 llvm::GlobalIFunc::create(DeclTy, 0, llvm::Function::ExternalLinkage,
5538 "", Resolver, &getModule());
5539 if (Entry) {
5540 if (GIF->getResolver() == Entry) {
5541 Diags.Report(IFA->getLocation(), diag::err_cyclic_alias) << 1;
5542 return;
5543 }
5544 assert(Entry->isDeclaration());
5545
5546 // If there is a declaration in the module, then we had an extern followed
5547 // by the ifunc, as in:
5548 // extern int test();
5549 // ...
5550 // int test() __attribute__((ifunc("resolver")));
5551 //
5552 // Remove it and replace uses of it with the ifunc.
5553 GIF->takeName(Entry);
5554
5555 Entry->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GIF,
5556 Entry->getType()));
5557 Entry->eraseFromParent();
5558 } else
5559 GIF->setName(MangledName);
5560
5561 SetCommonAttributes(GD, GIF);
5562 }
5563
getIntrinsic(unsigned IID,ArrayRef<llvm::Type * > Tys)5564 llvm::Function *CodeGenModule::getIntrinsic(unsigned IID,
5565 ArrayRef<llvm::Type*> Tys) {
5566 return llvm::Intrinsic::getDeclaration(&getModule(), (llvm::Intrinsic::ID)IID,
5567 Tys);
5568 }
5569
5570 static llvm::StringMapEntry<llvm::GlobalVariable *> &
GetConstantCFStringEntry(llvm::StringMap<llvm::GlobalVariable * > & Map,const StringLiteral * Literal,bool TargetIsLSB,bool & IsUTF16,unsigned & StringLength)5571 GetConstantCFStringEntry(llvm::StringMap<llvm::GlobalVariable *> &Map,
5572 const StringLiteral *Literal, bool TargetIsLSB,
5573 bool &IsUTF16, unsigned &StringLength) {
5574 StringRef String = Literal->getString();
5575 unsigned NumBytes = String.size();
5576
5577 // Check for simple case.
5578 if (!Literal->containsNonAsciiOrNull()) {
5579 StringLength = NumBytes;
5580 return *Map.insert(std::make_pair(String, nullptr)).first;
5581 }
5582
5583 // Otherwise, convert the UTF8 literals into a string of shorts.
5584 IsUTF16 = true;
5585
5586 SmallVector<llvm::UTF16, 128> ToBuf(NumBytes + 1); // +1 for ending nulls.
5587 const llvm::UTF8 *FromPtr = (const llvm::UTF8 *)String.data();
5588 llvm::UTF16 *ToPtr = &ToBuf[0];
5589
5590 (void)llvm::ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes, &ToPtr,
5591 ToPtr + NumBytes, llvm::strictConversion);
5592
5593 // ConvertUTF8toUTF16 returns the length in ToPtr.
5594 StringLength = ToPtr - &ToBuf[0];
5595
5596 // Add an explicit null.
5597 *ToPtr = 0;
5598 return *Map.insert(std::make_pair(
5599 StringRef(reinterpret_cast<const char *>(ToBuf.data()),
5600 (StringLength + 1) * 2),
5601 nullptr)).first;
5602 }
5603
5604 ConstantAddress
GetAddrOfConstantCFString(const StringLiteral * Literal)5605 CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) {
5606 unsigned StringLength = 0;
5607 bool isUTF16 = false;
5608 llvm::StringMapEntry<llvm::GlobalVariable *> &Entry =
5609 GetConstantCFStringEntry(CFConstantStringMap, Literal,
5610 getDataLayout().isLittleEndian(), isUTF16,
5611 StringLength);
5612
5613 if (auto *C = Entry.second)
5614 return ConstantAddress(
5615 C, C->getValueType(), CharUnits::fromQuantity(C->getAlignment()));
5616
5617 llvm::Constant *Zero = llvm::Constant::getNullValue(Int32Ty);
5618 llvm::Constant *Zeros[] = { Zero, Zero };
5619
5620 const ASTContext &Context = getContext();
5621 const llvm::Triple &Triple = getTriple();
5622
5623 const auto CFRuntime = getLangOpts().CFRuntime;
5624 const bool IsSwiftABI =
5625 static_cast<unsigned>(CFRuntime) >=
5626 static_cast<unsigned>(LangOptions::CoreFoundationABI::Swift);
5627 const bool IsSwift4_1 = CFRuntime == LangOptions::CoreFoundationABI::Swift4_1;
5628
5629 // If we don't already have it, get __CFConstantStringClassReference.
5630 if (!CFConstantStringClassRef) {
5631 const char *CFConstantStringClassName = "__CFConstantStringClassReference";
5632 llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy);
5633 Ty = llvm::ArrayType::get(Ty, 0);
5634
5635 switch (CFRuntime) {
5636 default: break;
5637 case LangOptions::CoreFoundationABI::Swift: [[fallthrough]];
5638 case LangOptions::CoreFoundationABI::Swift5_0:
5639 CFConstantStringClassName =
5640 Triple.isOSDarwin() ? "$s15SwiftFoundation19_NSCFConstantStringCN"
5641 : "$s10Foundation19_NSCFConstantStringCN";
5642 Ty = IntPtrTy;
5643 break;
5644 case LangOptions::CoreFoundationABI::Swift4_2:
5645 CFConstantStringClassName =
5646 Triple.isOSDarwin() ? "$S15SwiftFoundation19_NSCFConstantStringCN"
5647 : "$S10Foundation19_NSCFConstantStringCN";
5648 Ty = IntPtrTy;
5649 break;
5650 case LangOptions::CoreFoundationABI::Swift4_1:
5651 CFConstantStringClassName =
5652 Triple.isOSDarwin() ? "__T015SwiftFoundation19_NSCFConstantStringCN"
5653 : "__T010Foundation19_NSCFConstantStringCN";
5654 Ty = IntPtrTy;
5655 break;
5656 }
5657
5658 llvm::Constant *C = CreateRuntimeVariable(Ty, CFConstantStringClassName);
5659
5660 if (Triple.isOSBinFormatELF() || Triple.isOSBinFormatCOFF()) {
5661 llvm::GlobalValue *GV = nullptr;
5662
5663 if ((GV = dyn_cast<llvm::GlobalValue>(C))) {
5664 IdentifierInfo &II = Context.Idents.get(GV->getName());
5665 TranslationUnitDecl *TUDecl = Context.getTranslationUnitDecl();
5666 DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl);
5667
5668 const VarDecl *VD = nullptr;
5669 for (const auto *Result : DC->lookup(&II))
5670 if ((VD = dyn_cast<VarDecl>(Result)))
5671 break;
5672
5673 if (Triple.isOSBinFormatELF()) {
5674 if (!VD)
5675 GV->setLinkage(llvm::GlobalValue::ExternalLinkage);
5676 } else {
5677 GV->setLinkage(llvm::GlobalValue::ExternalLinkage);
5678 if (!VD || !VD->hasAttr<DLLExportAttr>())
5679 GV->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
5680 else
5681 GV->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
5682 }
5683
5684 setDSOLocal(GV);
5685 }
5686 }
5687
5688 // Decay array -> ptr
5689 CFConstantStringClassRef =
5690 IsSwiftABI ? llvm::ConstantExpr::getPtrToInt(C, Ty)
5691 : llvm::ConstantExpr::getGetElementPtr(Ty, C, Zeros);
5692 }
5693
5694 QualType CFTy = Context.getCFConstantStringType();
5695
5696 auto *STy = cast<llvm::StructType>(getTypes().ConvertType(CFTy));
5697
5698 ConstantInitBuilder Builder(*this);
5699 auto Fields = Builder.beginStruct(STy);
5700
5701 // Class pointer.
5702 Fields.add(cast<llvm::Constant>(CFConstantStringClassRef));
5703
5704 // Flags.
5705 if (IsSwiftABI) {
5706 Fields.addInt(IntPtrTy, IsSwift4_1 ? 0x05 : 0x01);
5707 Fields.addInt(Int64Ty, isUTF16 ? 0x07d0 : 0x07c8);
5708 } else {
5709 Fields.addInt(IntTy, isUTF16 ? 0x07d0 : 0x07C8);
5710 }
5711
5712 // String pointer.
5713 llvm::Constant *C = nullptr;
5714 if (isUTF16) {
5715 auto Arr = llvm::ArrayRef(
5716 reinterpret_cast<uint16_t *>(const_cast<char *>(Entry.first().data())),
5717 Entry.first().size() / 2);
5718 C = llvm::ConstantDataArray::get(VMContext, Arr);
5719 } else {
5720 C = llvm::ConstantDataArray::getString(VMContext, Entry.first());
5721 }
5722
5723 // Note: -fwritable-strings doesn't make the backing store strings of
5724 // CFStrings writable. (See <rdar://problem/10657500>)
5725 auto *GV =
5726 new llvm::GlobalVariable(getModule(), C->getType(), /*isConstant=*/true,
5727 llvm::GlobalValue::PrivateLinkage, C, ".str");
5728 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
5729 // Don't enforce the target's minimum global alignment, since the only use
5730 // of the string is via this class initializer.
5731 CharUnits Align = isUTF16 ? Context.getTypeAlignInChars(Context.ShortTy)
5732 : Context.getTypeAlignInChars(Context.CharTy);
5733 GV->setAlignment(Align.getAsAlign());
5734
5735 // FIXME: We set the section explicitly to avoid a bug in ld64 224.1.
5736 // Without it LLVM can merge the string with a non unnamed_addr one during
5737 // LTO. Doing that changes the section it ends in, which surprises ld64.
5738 if (Triple.isOSBinFormatMachO())
5739 GV->setSection(isUTF16 ? "__TEXT,__ustring"
5740 : "__TEXT,__cstring,cstring_literals");
5741 // Make sure the literal ends up in .rodata to allow for safe ICF and for
5742 // the static linker to adjust permissions to read-only later on.
5743 else if (Triple.isOSBinFormatELF())
5744 GV->setSection(".rodata");
5745
5746 // String.
5747 llvm::Constant *Str =
5748 llvm::ConstantExpr::getGetElementPtr(GV->getValueType(), GV, Zeros);
5749
5750 if (isUTF16)
5751 // Cast the UTF16 string to the correct type.
5752 Str = llvm::ConstantExpr::getBitCast(Str, Int8PtrTy);
5753 Fields.add(Str);
5754
5755 // String length.
5756 llvm::IntegerType *LengthTy =
5757 llvm::IntegerType::get(getModule().getContext(),
5758 Context.getTargetInfo().getLongWidth());
5759 if (IsSwiftABI) {
5760 if (CFRuntime == LangOptions::CoreFoundationABI::Swift4_1 ||
5761 CFRuntime == LangOptions::CoreFoundationABI::Swift4_2)
5762 LengthTy = Int32Ty;
5763 else
5764 LengthTy = IntPtrTy;
5765 }
5766 Fields.addInt(LengthTy, StringLength);
5767
5768 // Swift ABI requires 8-byte alignment to ensure that the _Atomic(uint64_t) is
5769 // properly aligned on 32-bit platforms.
5770 CharUnits Alignment =
5771 IsSwiftABI ? Context.toCharUnitsFromBits(64) : getPointerAlign();
5772
5773 // The struct.
5774 GV = Fields.finishAndCreateGlobal("_unnamed_cfstring_", Alignment,
5775 /*isConstant=*/false,
5776 llvm::GlobalVariable::PrivateLinkage);
5777 GV->addAttribute("objc_arc_inert");
5778 switch (Triple.getObjectFormat()) {
5779 case llvm::Triple::UnknownObjectFormat:
5780 llvm_unreachable("unknown file format");
5781 case llvm::Triple::DXContainer:
5782 case llvm::Triple::GOFF:
5783 case llvm::Triple::SPIRV:
5784 case llvm::Triple::XCOFF:
5785 llvm_unreachable("unimplemented");
5786 case llvm::Triple::COFF:
5787 case llvm::Triple::ELF:
5788 case llvm::Triple::Wasm:
5789 GV->setSection("cfstring");
5790 break;
5791 case llvm::Triple::MachO:
5792 GV->setSection("__DATA,__cfstring");
5793 break;
5794 }
5795 Entry.second = GV;
5796
5797 return ConstantAddress(GV, GV->getValueType(), Alignment);
5798 }
5799
getExpressionLocationsEnabled() const5800 bool CodeGenModule::getExpressionLocationsEnabled() const {
5801 return !CodeGenOpts.EmitCodeView || CodeGenOpts.DebugColumnInfo;
5802 }
5803
getObjCFastEnumerationStateType()5804 QualType CodeGenModule::getObjCFastEnumerationStateType() {
5805 if (ObjCFastEnumerationStateType.isNull()) {
5806 RecordDecl *D = Context.buildImplicitRecord("__objcFastEnumerationState");
5807 D->startDefinition();
5808
5809 QualType FieldTypes[] = {
5810 Context.UnsignedLongTy,
5811 Context.getPointerType(Context.getObjCIdType()),
5812 Context.getPointerType(Context.UnsignedLongTy),
5813 Context.getConstantArrayType(Context.UnsignedLongTy,
5814 llvm::APInt(32, 5), nullptr, ArrayType::Normal, 0)
5815 };
5816
5817 for (size_t i = 0; i < 4; ++i) {
5818 FieldDecl *Field = FieldDecl::Create(Context,
5819 D,
5820 SourceLocation(),
5821 SourceLocation(), nullptr,
5822 FieldTypes[i], /*TInfo=*/nullptr,
5823 /*BitWidth=*/nullptr,
5824 /*Mutable=*/false,
5825 ICIS_NoInit);
5826 Field->setAccess(AS_public);
5827 D->addDecl(Field);
5828 }
5829
5830 D->completeDefinition();
5831 ObjCFastEnumerationStateType = Context.getTagDeclType(D);
5832 }
5833
5834 return ObjCFastEnumerationStateType;
5835 }
5836
5837 llvm::Constant *
GetConstantArrayFromStringLiteral(const StringLiteral * E)5838 CodeGenModule::GetConstantArrayFromStringLiteral(const StringLiteral *E) {
5839 assert(!E->getType()->isPointerType() && "Strings are always arrays");
5840
5841 // Don't emit it as the address of the string, emit the string data itself
5842 // as an inline array.
5843 if (E->getCharByteWidth() == 1) {
5844 SmallString<64> Str(E->getString());
5845
5846 // Resize the string to the right size, which is indicated by its type.
5847 const ConstantArrayType *CAT = Context.getAsConstantArrayType(E->getType());
5848 Str.resize(CAT->getSize().getZExtValue());
5849 return llvm::ConstantDataArray::getString(VMContext, Str, false);
5850 }
5851
5852 auto *AType = cast<llvm::ArrayType>(getTypes().ConvertType(E->getType()));
5853 llvm::Type *ElemTy = AType->getElementType();
5854 unsigned NumElements = AType->getNumElements();
5855
5856 // Wide strings have either 2-byte or 4-byte elements.
5857 if (ElemTy->getPrimitiveSizeInBits() == 16) {
5858 SmallVector<uint16_t, 32> Elements;
5859 Elements.reserve(NumElements);
5860
5861 for(unsigned i = 0, e = E->getLength(); i != e; ++i)
5862 Elements.push_back(E->getCodeUnit(i));
5863 Elements.resize(NumElements);
5864 return llvm::ConstantDataArray::get(VMContext, Elements);
5865 }
5866
5867 assert(ElemTy->getPrimitiveSizeInBits() == 32);
5868 SmallVector<uint32_t, 32> Elements;
5869 Elements.reserve(NumElements);
5870
5871 for(unsigned i = 0, e = E->getLength(); i != e; ++i)
5872 Elements.push_back(E->getCodeUnit(i));
5873 Elements.resize(NumElements);
5874 return llvm::ConstantDataArray::get(VMContext, Elements);
5875 }
5876
5877 static llvm::GlobalVariable *
GenerateStringLiteral(llvm::Constant * C,llvm::GlobalValue::LinkageTypes LT,CodeGenModule & CGM,StringRef GlobalName,CharUnits Alignment)5878 GenerateStringLiteral(llvm::Constant *C, llvm::GlobalValue::LinkageTypes LT,
5879 CodeGenModule &CGM, StringRef GlobalName,
5880 CharUnits Alignment) {
5881 unsigned AddrSpace = CGM.getContext().getTargetAddressSpace(
5882 CGM.GetGlobalConstantAddressSpace());
5883
5884 llvm::Module &M = CGM.getModule();
5885 // Create a global variable for this string
5886 auto *GV = new llvm::GlobalVariable(
5887 M, C->getType(), !CGM.getLangOpts().WritableStrings, LT, C, GlobalName,
5888 nullptr, llvm::GlobalVariable::NotThreadLocal, AddrSpace);
5889 GV->setAlignment(Alignment.getAsAlign());
5890 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
5891 if (GV->isWeakForLinker()) {
5892 assert(CGM.supportsCOMDAT() && "Only COFF uses weak string literals");
5893 GV->setComdat(M.getOrInsertComdat(GV->getName()));
5894 }
5895 CGM.setDSOLocal(GV);
5896
5897 return GV;
5898 }
5899
5900 /// GetAddrOfConstantStringFromLiteral - Return a pointer to a
5901 /// constant array for the given string literal.
5902 ConstantAddress
GetAddrOfConstantStringFromLiteral(const StringLiteral * S,StringRef Name)5903 CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S,
5904 StringRef Name) {
5905 CharUnits Alignment = getContext().getAlignOfGlobalVarInChars(S->getType());
5906
5907 llvm::Constant *C = GetConstantArrayFromStringLiteral(S);
5908 llvm::GlobalVariable **Entry = nullptr;
5909 if (!LangOpts.WritableStrings) {
5910 Entry = &ConstantStringMap[C];
5911 if (auto GV = *Entry) {
5912 if (uint64_t(Alignment.getQuantity()) > GV->getAlignment())
5913 GV->setAlignment(Alignment.getAsAlign());
5914 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV),
5915 GV->getValueType(), Alignment);
5916 }
5917 }
5918
5919 SmallString<256> MangledNameBuffer;
5920 StringRef GlobalVariableName;
5921 llvm::GlobalValue::LinkageTypes LT;
5922
5923 // Mangle the string literal if that's how the ABI merges duplicate strings.
5924 // Don't do it if they are writable, since we don't want writes in one TU to
5925 // affect strings in another.
5926 if (getCXXABI().getMangleContext().shouldMangleStringLiteral(S) &&
5927 !LangOpts.WritableStrings) {
5928 llvm::raw_svector_ostream Out(MangledNameBuffer);
5929 getCXXABI().getMangleContext().mangleStringLiteral(S, Out);
5930 LT = llvm::GlobalValue::LinkOnceODRLinkage;
5931 GlobalVariableName = MangledNameBuffer;
5932 } else {
5933 LT = llvm::GlobalValue::PrivateLinkage;
5934 GlobalVariableName = Name;
5935 }
5936
5937 auto GV = GenerateStringLiteral(C, LT, *this, GlobalVariableName, Alignment);
5938
5939 CGDebugInfo *DI = getModuleDebugInfo();
5940 if (DI && getCodeGenOpts().hasReducedDebugInfo())
5941 DI->AddStringLiteralDebugInfo(GV, S);
5942
5943 if (Entry)
5944 *Entry = GV;
5945
5946 SanitizerMD->reportGlobal(GV, S->getStrTokenLoc(0), "<string literal>");
5947
5948 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV),
5949 GV->getValueType(), Alignment);
5950 }
5951
5952 /// GetAddrOfConstantStringFromObjCEncode - Return a pointer to a constant
5953 /// array for the given ObjCEncodeExpr node.
5954 ConstantAddress
GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr * E)5955 CodeGenModule::GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *E) {
5956 std::string Str;
5957 getContext().getObjCEncodingForType(E->getEncodedType(), Str);
5958
5959 return GetAddrOfConstantCString(Str);
5960 }
5961
5962 /// GetAddrOfConstantCString - Returns a pointer to a character array containing
5963 /// the literal and a terminating '\0' character.
5964 /// The result has pointer to array type.
GetAddrOfConstantCString(const std::string & Str,const char * GlobalName)5965 ConstantAddress CodeGenModule::GetAddrOfConstantCString(
5966 const std::string &Str, const char *GlobalName) {
5967 StringRef StrWithNull(Str.c_str(), Str.size() + 1);
5968 CharUnits Alignment =
5969 getContext().getAlignOfGlobalVarInChars(getContext().CharTy);
5970
5971 llvm::Constant *C =
5972 llvm::ConstantDataArray::getString(getLLVMContext(), StrWithNull, false);
5973
5974 // Don't share any string literals if strings aren't constant.
5975 llvm::GlobalVariable **Entry = nullptr;
5976 if (!LangOpts.WritableStrings) {
5977 Entry = &ConstantStringMap[C];
5978 if (auto GV = *Entry) {
5979 if (uint64_t(Alignment.getQuantity()) > GV->getAlignment())
5980 GV->setAlignment(Alignment.getAsAlign());
5981 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV),
5982 GV->getValueType(), Alignment);
5983 }
5984 }
5985
5986 // Get the default prefix if a name wasn't specified.
5987 if (!GlobalName)
5988 GlobalName = ".str";
5989 // Create a global variable for this.
5990 auto GV = GenerateStringLiteral(C, llvm::GlobalValue::PrivateLinkage, *this,
5991 GlobalName, Alignment);
5992 if (Entry)
5993 *Entry = GV;
5994
5995 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV),
5996 GV->getValueType(), Alignment);
5997 }
5998
GetAddrOfGlobalTemporary(const MaterializeTemporaryExpr * E,const Expr * Init)5999 ConstantAddress CodeGenModule::GetAddrOfGlobalTemporary(
6000 const MaterializeTemporaryExpr *E, const Expr *Init) {
6001 assert((E->getStorageDuration() == SD_Static ||
6002 E->getStorageDuration() == SD_Thread) && "not a global temporary");
6003 const auto *VD = cast<VarDecl>(E->getExtendingDecl());
6004
6005 // If we're not materializing a subobject of the temporary, keep the
6006 // cv-qualifiers from the type of the MaterializeTemporaryExpr.
6007 QualType MaterializedType = Init->getType();
6008 if (Init == E->getSubExpr())
6009 MaterializedType = E->getType();
6010
6011 CharUnits Align = getContext().getTypeAlignInChars(MaterializedType);
6012
6013 auto InsertResult = MaterializedGlobalTemporaryMap.insert({E, nullptr});
6014 if (!InsertResult.second) {
6015 // We've seen this before: either we already created it or we're in the
6016 // process of doing so.
6017 if (!InsertResult.first->second) {
6018 // We recursively re-entered this function, probably during emission of
6019 // the initializer. Create a placeholder. We'll clean this up in the
6020 // outer call, at the end of this function.
6021 llvm::Type *Type = getTypes().ConvertTypeForMem(MaterializedType);
6022 InsertResult.first->second = new llvm::GlobalVariable(
6023 getModule(), Type, false, llvm::GlobalVariable::InternalLinkage,
6024 nullptr);
6025 }
6026 return ConstantAddress(InsertResult.first->second,
6027 llvm::cast<llvm::GlobalVariable>(
6028 InsertResult.first->second->stripPointerCasts())
6029 ->getValueType(),
6030 Align);
6031 }
6032
6033 // FIXME: If an externally-visible declaration extends multiple temporaries,
6034 // we need to give each temporary the same name in every translation unit (and
6035 // we also need to make the temporaries externally-visible).
6036 SmallString<256> Name;
6037 llvm::raw_svector_ostream Out(Name);
6038 getCXXABI().getMangleContext().mangleReferenceTemporary(
6039 VD, E->getManglingNumber(), Out);
6040
6041 APValue *Value = nullptr;
6042 if (E->getStorageDuration() == SD_Static && VD && VD->evaluateValue()) {
6043 // If the initializer of the extending declaration is a constant
6044 // initializer, we should have a cached constant initializer for this
6045 // temporary. Note that this might have a different value from the value
6046 // computed by evaluating the initializer if the surrounding constant
6047 // expression modifies the temporary.
6048 Value = E->getOrCreateValue(false);
6049 }
6050
6051 // Try evaluating it now, it might have a constant initializer.
6052 Expr::EvalResult EvalResult;
6053 if (!Value && Init->EvaluateAsRValue(EvalResult, getContext()) &&
6054 !EvalResult.hasSideEffects())
6055 Value = &EvalResult.Val;
6056
6057 LangAS AddrSpace =
6058 VD ? GetGlobalVarAddressSpace(VD) : MaterializedType.getAddressSpace();
6059
6060 std::optional<ConstantEmitter> emitter;
6061 llvm::Constant *InitialValue = nullptr;
6062 bool Constant = false;
6063 llvm::Type *Type;
6064 if (Value) {
6065 // The temporary has a constant initializer, use it.
6066 emitter.emplace(*this);
6067 InitialValue = emitter->emitForInitializer(*Value, AddrSpace,
6068 MaterializedType);
6069 Constant = isTypeConstant(MaterializedType, /*ExcludeCtor*/Value);
6070 Type = InitialValue->getType();
6071 } else {
6072 // No initializer, the initialization will be provided when we
6073 // initialize the declaration which performed lifetime extension.
6074 Type = getTypes().ConvertTypeForMem(MaterializedType);
6075 }
6076
6077 // Create a global variable for this lifetime-extended temporary.
6078 llvm::GlobalValue::LinkageTypes Linkage =
6079 getLLVMLinkageVarDefinition(VD, Constant);
6080 if (Linkage == llvm::GlobalVariable::ExternalLinkage) {
6081 const VarDecl *InitVD;
6082 if (VD->isStaticDataMember() && VD->getAnyInitializer(InitVD) &&
6083 isa<CXXRecordDecl>(InitVD->getLexicalDeclContext())) {
6084 // Temporaries defined inside a class get linkonce_odr linkage because the
6085 // class can be defined in multiple translation units.
6086 Linkage = llvm::GlobalVariable::LinkOnceODRLinkage;
6087 } else {
6088 // There is no need for this temporary to have external linkage if the
6089 // VarDecl has external linkage.
6090 Linkage = llvm::GlobalVariable::InternalLinkage;
6091 }
6092 }
6093 auto TargetAS = getContext().getTargetAddressSpace(AddrSpace);
6094 auto *GV = new llvm::GlobalVariable(
6095 getModule(), Type, Constant, Linkage, InitialValue, Name.c_str(),
6096 /*InsertBefore=*/nullptr, llvm::GlobalVariable::NotThreadLocal, TargetAS);
6097 if (emitter) emitter->finalize(GV);
6098 // Don't assign dllimport or dllexport to local linkage globals.
6099 if (!llvm::GlobalValue::isLocalLinkage(Linkage)) {
6100 setGVProperties(GV, VD);
6101 if (GV->getDLLStorageClass() == llvm::GlobalVariable::DLLExportStorageClass)
6102 // The reference temporary should never be dllexport.
6103 GV->setDLLStorageClass(llvm::GlobalVariable::DefaultStorageClass);
6104 }
6105 GV->setAlignment(Align.getAsAlign());
6106 if (supportsCOMDAT() && GV->isWeakForLinker())
6107 GV->setComdat(TheModule.getOrInsertComdat(GV->getName()));
6108 if (VD->getTLSKind())
6109 setTLSMode(GV, *VD);
6110 llvm::Constant *CV = GV;
6111 if (AddrSpace != LangAS::Default)
6112 CV = getTargetCodeGenInfo().performAddrSpaceCast(
6113 *this, GV, AddrSpace, LangAS::Default,
6114 Type->getPointerTo(
6115 getContext().getTargetAddressSpace(LangAS::Default)));
6116
6117 // Update the map with the new temporary. If we created a placeholder above,
6118 // replace it with the new global now.
6119 llvm::Constant *&Entry = MaterializedGlobalTemporaryMap[E];
6120 if (Entry) {
6121 Entry->replaceAllUsesWith(
6122 llvm::ConstantExpr::getBitCast(CV, Entry->getType()));
6123 llvm::cast<llvm::GlobalVariable>(Entry)->eraseFromParent();
6124 }
6125 Entry = CV;
6126
6127 return ConstantAddress(CV, Type, Align);
6128 }
6129
6130 /// EmitObjCPropertyImplementations - Emit information for synthesized
6131 /// properties for an implementation.
EmitObjCPropertyImplementations(const ObjCImplementationDecl * D)6132 void CodeGenModule::EmitObjCPropertyImplementations(const
6133 ObjCImplementationDecl *D) {
6134 for (const auto *PID : D->property_impls()) {
6135 // Dynamic is just for type-checking.
6136 if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) {
6137 ObjCPropertyDecl *PD = PID->getPropertyDecl();
6138
6139 // Determine which methods need to be implemented, some may have
6140 // been overridden. Note that ::isPropertyAccessor is not the method
6141 // we want, that just indicates if the decl came from a
6142 // property. What we want to know is if the method is defined in
6143 // this implementation.
6144 auto *Getter = PID->getGetterMethodDecl();
6145 if (!Getter || Getter->isSynthesizedAccessorStub())
6146 CodeGenFunction(*this).GenerateObjCGetter(
6147 const_cast<ObjCImplementationDecl *>(D), PID);
6148 auto *Setter = PID->getSetterMethodDecl();
6149 if (!PD->isReadOnly() && (!Setter || Setter->isSynthesizedAccessorStub()))
6150 CodeGenFunction(*this).GenerateObjCSetter(
6151 const_cast<ObjCImplementationDecl *>(D), PID);
6152 }
6153 }
6154 }
6155
needsDestructMethod(ObjCImplementationDecl * impl)6156 static bool needsDestructMethod(ObjCImplementationDecl *impl) {
6157 const ObjCInterfaceDecl *iface = impl->getClassInterface();
6158 for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
6159 ivar; ivar = ivar->getNextIvar())
6160 if (ivar->getType().isDestructedType())
6161 return true;
6162
6163 return false;
6164 }
6165
AllTrivialInitializers(CodeGenModule & CGM,ObjCImplementationDecl * D)6166 static bool AllTrivialInitializers(CodeGenModule &CGM,
6167 ObjCImplementationDecl *D) {
6168 CodeGenFunction CGF(CGM);
6169 for (ObjCImplementationDecl::init_iterator B = D->init_begin(),
6170 E = D->init_end(); B != E; ++B) {
6171 CXXCtorInitializer *CtorInitExp = *B;
6172 Expr *Init = CtorInitExp->getInit();
6173 if (!CGF.isTrivialInitializer(Init))
6174 return false;
6175 }
6176 return true;
6177 }
6178
6179 /// EmitObjCIvarInitializations - Emit information for ivar initialization
6180 /// for an implementation.
EmitObjCIvarInitializations(ObjCImplementationDecl * D)6181 void CodeGenModule::EmitObjCIvarInitializations(ObjCImplementationDecl *D) {
6182 // We might need a .cxx_destruct even if we don't have any ivar initializers.
6183 if (needsDestructMethod(D)) {
6184 IdentifierInfo *II = &getContext().Idents.get(".cxx_destruct");
6185 Selector cxxSelector = getContext().Selectors.getSelector(0, &II);
6186 ObjCMethodDecl *DTORMethod = ObjCMethodDecl::Create(
6187 getContext(), D->getLocation(), D->getLocation(), cxxSelector,
6188 getContext().VoidTy, nullptr, D,
6189 /*isInstance=*/true, /*isVariadic=*/false,
6190 /*isPropertyAccessor=*/true, /*isSynthesizedAccessorStub=*/false,
6191 /*isImplicitlyDeclared=*/true,
6192 /*isDefined=*/false, ObjCMethodDecl::Required);
6193 D->addInstanceMethod(DTORMethod);
6194 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, DTORMethod, false);
6195 D->setHasDestructors(true);
6196 }
6197
6198 // If the implementation doesn't have any ivar initializers, we don't need
6199 // a .cxx_construct.
6200 if (D->getNumIvarInitializers() == 0 ||
6201 AllTrivialInitializers(*this, D))
6202 return;
6203
6204 IdentifierInfo *II = &getContext().Idents.get(".cxx_construct");
6205 Selector cxxSelector = getContext().Selectors.getSelector(0, &II);
6206 // The constructor returns 'self'.
6207 ObjCMethodDecl *CTORMethod = ObjCMethodDecl::Create(
6208 getContext(), D->getLocation(), D->getLocation(), cxxSelector,
6209 getContext().getObjCIdType(), nullptr, D, /*isInstance=*/true,
6210 /*isVariadic=*/false,
6211 /*isPropertyAccessor=*/true, /*isSynthesizedAccessorStub=*/false,
6212 /*isImplicitlyDeclared=*/true,
6213 /*isDefined=*/false, ObjCMethodDecl::Required);
6214 D->addInstanceMethod(CTORMethod);
6215 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, CTORMethod, true);
6216 D->setHasNonZeroConstructors(true);
6217 }
6218
6219 // EmitLinkageSpec - Emit all declarations in a linkage spec.
EmitLinkageSpec(const LinkageSpecDecl * LSD)6220 void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) {
6221 if (LSD->getLanguage() != LinkageSpecDecl::lang_c &&
6222 LSD->getLanguage() != LinkageSpecDecl::lang_cxx) {
6223 ErrorUnsupported(LSD, "linkage spec");
6224 return;
6225 }
6226
6227 EmitDeclContext(LSD);
6228 }
6229
EmitTopLevelStmt(const TopLevelStmtDecl * D)6230 void CodeGenModule::EmitTopLevelStmt(const TopLevelStmtDecl *D) {
6231 std::unique_ptr<CodeGenFunction> &CurCGF =
6232 GlobalTopLevelStmtBlockInFlight.first;
6233
6234 // We emitted a top-level stmt but after it there is initialization.
6235 // Stop squashing the top-level stmts into a single function.
6236 if (CurCGF && CXXGlobalInits.back() != CurCGF->CurFn) {
6237 CurCGF->FinishFunction(D->getEndLoc());
6238 CurCGF = nullptr;
6239 }
6240
6241 if (!CurCGF) {
6242 // void __stmts__N(void)
6243 // FIXME: Ask the ABI name mangler to pick a name.
6244 std::string Name = "__stmts__" + llvm::utostr(CXXGlobalInits.size());
6245 FunctionArgList Args;
6246 QualType RetTy = getContext().VoidTy;
6247 const CGFunctionInfo &FnInfo =
6248 getTypes().arrangeBuiltinFunctionDeclaration(RetTy, Args);
6249 llvm::FunctionType *FnTy = getTypes().GetFunctionType(FnInfo);
6250 llvm::Function *Fn = llvm::Function::Create(
6251 FnTy, llvm::GlobalValue::InternalLinkage, Name, &getModule());
6252
6253 CurCGF.reset(new CodeGenFunction(*this));
6254 GlobalTopLevelStmtBlockInFlight.second = D;
6255 CurCGF->StartFunction(GlobalDecl(), RetTy, Fn, FnInfo, Args,
6256 D->getBeginLoc(), D->getBeginLoc());
6257 CXXGlobalInits.push_back(Fn);
6258 }
6259
6260 CurCGF->EmitStmt(D->getStmt());
6261 }
6262
EmitDeclContext(const DeclContext * DC)6263 void CodeGenModule::EmitDeclContext(const DeclContext *DC) {
6264 for (auto *I : DC->decls()) {
6265 // Unlike other DeclContexts, the contents of an ObjCImplDecl at TU scope
6266 // are themselves considered "top-level", so EmitTopLevelDecl on an
6267 // ObjCImplDecl does not recursively visit them. We need to do that in
6268 // case they're nested inside another construct (LinkageSpecDecl /
6269 // ExportDecl) that does stop them from being considered "top-level".
6270 if (auto *OID = dyn_cast<ObjCImplDecl>(I)) {
6271 for (auto *M : OID->methods())
6272 EmitTopLevelDecl(M);
6273 }
6274
6275 EmitTopLevelDecl(I);
6276 }
6277 }
6278
6279 /// EmitTopLevelDecl - Emit code for a single top level declaration.
EmitTopLevelDecl(Decl * D)6280 void CodeGenModule::EmitTopLevelDecl(Decl *D) {
6281 // Ignore dependent declarations.
6282 if (D->isTemplated())
6283 return;
6284
6285 // Consteval function shouldn't be emitted.
6286 if (auto *FD = dyn_cast<FunctionDecl>(D))
6287 if (FD->isConsteval())
6288 return;
6289
6290 switch (D->getKind()) {
6291 case Decl::CXXConversion:
6292 case Decl::CXXMethod:
6293 case Decl::Function:
6294 EmitGlobal(cast<FunctionDecl>(D));
6295 // Always provide some coverage mapping
6296 // even for the functions that aren't emitted.
6297 AddDeferredUnusedCoverageMapping(D);
6298 break;
6299
6300 case Decl::CXXDeductionGuide:
6301 // Function-like, but does not result in code emission.
6302 break;
6303
6304 case Decl::Var:
6305 case Decl::Decomposition:
6306 case Decl::VarTemplateSpecialization:
6307 EmitGlobal(cast<VarDecl>(D));
6308 if (auto *DD = dyn_cast<DecompositionDecl>(D))
6309 for (auto *B : DD->bindings())
6310 if (auto *HD = B->getHoldingVar())
6311 EmitGlobal(HD);
6312 break;
6313
6314 // Indirect fields from global anonymous structs and unions can be
6315 // ignored; only the actual variable requires IR gen support.
6316 case Decl::IndirectField:
6317 break;
6318
6319 // C++ Decls
6320 case Decl::Namespace:
6321 EmitDeclContext(cast<NamespaceDecl>(D));
6322 break;
6323 case Decl::ClassTemplateSpecialization: {
6324 const auto *Spec = cast<ClassTemplateSpecializationDecl>(D);
6325 if (CGDebugInfo *DI = getModuleDebugInfo())
6326 if (Spec->getSpecializationKind() ==
6327 TSK_ExplicitInstantiationDefinition &&
6328 Spec->hasDefinition())
6329 DI->completeTemplateDefinition(*Spec);
6330 } [[fallthrough]];
6331 case Decl::CXXRecord: {
6332 CXXRecordDecl *CRD = cast<CXXRecordDecl>(D);
6333 if (CGDebugInfo *DI = getModuleDebugInfo()) {
6334 if (CRD->hasDefinition())
6335 DI->EmitAndRetainType(getContext().getRecordType(cast<RecordDecl>(D)));
6336 if (auto *ES = D->getASTContext().getExternalSource())
6337 if (ES->hasExternalDefinitions(D) == ExternalASTSource::EK_Never)
6338 DI->completeUnusedClass(*CRD);
6339 }
6340 // Emit any static data members, they may be definitions.
6341 for (auto *I : CRD->decls())
6342 if (isa<VarDecl>(I) || isa<CXXRecordDecl>(I))
6343 EmitTopLevelDecl(I);
6344 break;
6345 }
6346 // No code generation needed.
6347 case Decl::UsingShadow:
6348 case Decl::ClassTemplate:
6349 case Decl::VarTemplate:
6350 case Decl::Concept:
6351 case Decl::VarTemplatePartialSpecialization:
6352 case Decl::FunctionTemplate:
6353 case Decl::TypeAliasTemplate:
6354 case Decl::Block:
6355 case Decl::Empty:
6356 case Decl::Binding:
6357 break;
6358 case Decl::Using: // using X; [C++]
6359 if (CGDebugInfo *DI = getModuleDebugInfo())
6360 DI->EmitUsingDecl(cast<UsingDecl>(*D));
6361 break;
6362 case Decl::UsingEnum: // using enum X; [C++]
6363 if (CGDebugInfo *DI = getModuleDebugInfo())
6364 DI->EmitUsingEnumDecl(cast<UsingEnumDecl>(*D));
6365 break;
6366 case Decl::NamespaceAlias:
6367 if (CGDebugInfo *DI = getModuleDebugInfo())
6368 DI->EmitNamespaceAlias(cast<NamespaceAliasDecl>(*D));
6369 break;
6370 case Decl::UsingDirective: // using namespace X; [C++]
6371 if (CGDebugInfo *DI = getModuleDebugInfo())
6372 DI->EmitUsingDirective(cast<UsingDirectiveDecl>(*D));
6373 break;
6374 case Decl::CXXConstructor:
6375 getCXXABI().EmitCXXConstructors(cast<CXXConstructorDecl>(D));
6376 break;
6377 case Decl::CXXDestructor:
6378 getCXXABI().EmitCXXDestructors(cast<CXXDestructorDecl>(D));
6379 break;
6380
6381 case Decl::StaticAssert:
6382 // Nothing to do.
6383 break;
6384
6385 // Objective-C Decls
6386
6387 // Forward declarations, no (immediate) code generation.
6388 case Decl::ObjCInterface:
6389 case Decl::ObjCCategory:
6390 break;
6391
6392 case Decl::ObjCProtocol: {
6393 auto *Proto = cast<ObjCProtocolDecl>(D);
6394 if (Proto->isThisDeclarationADefinition())
6395 ObjCRuntime->GenerateProtocol(Proto);
6396 break;
6397 }
6398
6399 case Decl::ObjCCategoryImpl:
6400 // Categories have properties but don't support synthesize so we
6401 // can ignore them here.
6402 ObjCRuntime->GenerateCategory(cast<ObjCCategoryImplDecl>(D));
6403 break;
6404
6405 case Decl::ObjCImplementation: {
6406 auto *OMD = cast<ObjCImplementationDecl>(D);
6407 EmitObjCPropertyImplementations(OMD);
6408 EmitObjCIvarInitializations(OMD);
6409 ObjCRuntime->GenerateClass(OMD);
6410 // Emit global variable debug information.
6411 if (CGDebugInfo *DI = getModuleDebugInfo())
6412 if (getCodeGenOpts().hasReducedDebugInfo())
6413 DI->getOrCreateInterfaceType(getContext().getObjCInterfaceType(
6414 OMD->getClassInterface()), OMD->getLocation());
6415 break;
6416 }
6417 case Decl::ObjCMethod: {
6418 auto *OMD = cast<ObjCMethodDecl>(D);
6419 // If this is not a prototype, emit the body.
6420 if (OMD->getBody())
6421 CodeGenFunction(*this).GenerateObjCMethod(OMD);
6422 break;
6423 }
6424 case Decl::ObjCCompatibleAlias:
6425 ObjCRuntime->RegisterAlias(cast<ObjCCompatibleAliasDecl>(D));
6426 break;
6427
6428 case Decl::PragmaComment: {
6429 const auto *PCD = cast<PragmaCommentDecl>(D);
6430 switch (PCD->getCommentKind()) {
6431 case PCK_Unknown:
6432 llvm_unreachable("unexpected pragma comment kind");
6433 case PCK_Linker:
6434 AppendLinkerOptions(PCD->getArg());
6435 break;
6436 case PCK_Lib:
6437 AddDependentLib(PCD->getArg());
6438 break;
6439 case PCK_Compiler:
6440 case PCK_ExeStr:
6441 case PCK_User:
6442 break; // We ignore all of these.
6443 }
6444 break;
6445 }
6446
6447 case Decl::PragmaDetectMismatch: {
6448 const auto *PDMD = cast<PragmaDetectMismatchDecl>(D);
6449 AddDetectMismatch(PDMD->getName(), PDMD->getValue());
6450 break;
6451 }
6452
6453 case Decl::LinkageSpec:
6454 EmitLinkageSpec(cast<LinkageSpecDecl>(D));
6455 break;
6456
6457 case Decl::FileScopeAsm: {
6458 // File-scope asm is ignored during device-side CUDA compilation.
6459 if (LangOpts.CUDA && LangOpts.CUDAIsDevice)
6460 break;
6461 // File-scope asm is ignored during device-side OpenMP compilation.
6462 if (LangOpts.OpenMPIsDevice)
6463 break;
6464 // File-scope asm is ignored during device-side SYCL compilation.
6465 if (LangOpts.SYCLIsDevice)
6466 break;
6467 auto *AD = cast<FileScopeAsmDecl>(D);
6468 getModule().appendModuleInlineAsm(AD->getAsmString()->getString());
6469 break;
6470 }
6471
6472 case Decl::TopLevelStmt:
6473 EmitTopLevelStmt(cast<TopLevelStmtDecl>(D));
6474 break;
6475
6476 case Decl::Import: {
6477 auto *Import = cast<ImportDecl>(D);
6478
6479 // If we've already imported this module, we're done.
6480 if (!ImportedModules.insert(Import->getImportedModule()))
6481 break;
6482
6483 // Emit debug information for direct imports.
6484 if (!Import->getImportedOwningModule()) {
6485 if (CGDebugInfo *DI = getModuleDebugInfo())
6486 DI->EmitImportDecl(*Import);
6487 }
6488
6489 // For C++ standard modules we are done - we will call the module
6490 // initializer for imported modules, and that will likewise call those for
6491 // any imports it has.
6492 if (CXX20ModuleInits && Import->getImportedOwningModule() &&
6493 !Import->getImportedOwningModule()->isModuleMapModule())
6494 break;
6495
6496 // For clang C++ module map modules the initializers for sub-modules are
6497 // emitted here.
6498
6499 // Find all of the submodules and emit the module initializers.
6500 llvm::SmallPtrSet<clang::Module *, 16> Visited;
6501 SmallVector<clang::Module *, 16> Stack;
6502 Visited.insert(Import->getImportedModule());
6503 Stack.push_back(Import->getImportedModule());
6504
6505 while (!Stack.empty()) {
6506 clang::Module *Mod = Stack.pop_back_val();
6507 if (!EmittedModuleInitializers.insert(Mod).second)
6508 continue;
6509
6510 for (auto *D : Context.getModuleInitializers(Mod))
6511 EmitTopLevelDecl(D);
6512
6513 // Visit the submodules of this module.
6514 for (clang::Module::submodule_iterator Sub = Mod->submodule_begin(),
6515 SubEnd = Mod->submodule_end();
6516 Sub != SubEnd; ++Sub) {
6517 // Skip explicit children; they need to be explicitly imported to emit
6518 // the initializers.
6519 if ((*Sub)->IsExplicit)
6520 continue;
6521
6522 if (Visited.insert(*Sub).second)
6523 Stack.push_back(*Sub);
6524 }
6525 }
6526 break;
6527 }
6528
6529 case Decl::Export:
6530 EmitDeclContext(cast<ExportDecl>(D));
6531 break;
6532
6533 case Decl::OMPThreadPrivate:
6534 EmitOMPThreadPrivateDecl(cast<OMPThreadPrivateDecl>(D));
6535 break;
6536
6537 case Decl::OMPAllocate:
6538 EmitOMPAllocateDecl(cast<OMPAllocateDecl>(D));
6539 break;
6540
6541 case Decl::OMPDeclareReduction:
6542 EmitOMPDeclareReduction(cast<OMPDeclareReductionDecl>(D));
6543 break;
6544
6545 case Decl::OMPDeclareMapper:
6546 EmitOMPDeclareMapper(cast<OMPDeclareMapperDecl>(D));
6547 break;
6548
6549 case Decl::OMPRequires:
6550 EmitOMPRequiresDecl(cast<OMPRequiresDecl>(D));
6551 break;
6552
6553 case Decl::Typedef:
6554 case Decl::TypeAlias: // using foo = bar; [C++11]
6555 if (CGDebugInfo *DI = getModuleDebugInfo())
6556 DI->EmitAndRetainType(
6557 getContext().getTypedefType(cast<TypedefNameDecl>(D)));
6558 break;
6559
6560 case Decl::Record:
6561 if (CGDebugInfo *DI = getModuleDebugInfo())
6562 if (cast<RecordDecl>(D)->getDefinition())
6563 DI->EmitAndRetainType(getContext().getRecordType(cast<RecordDecl>(D)));
6564 break;
6565
6566 case Decl::Enum:
6567 if (CGDebugInfo *DI = getModuleDebugInfo())
6568 if (cast<EnumDecl>(D)->getDefinition())
6569 DI->EmitAndRetainType(getContext().getEnumType(cast<EnumDecl>(D)));
6570 break;
6571
6572 case Decl::HLSLBuffer:
6573 getHLSLRuntime().addBuffer(cast<HLSLBufferDecl>(D));
6574 break;
6575
6576 default:
6577 // Make sure we handled everything we should, every other kind is a
6578 // non-top-level decl. FIXME: Would be nice to have an isTopLevelDeclKind
6579 // function. Need to recode Decl::Kind to do that easily.
6580 assert(isa<TypeDecl>(D) && "Unsupported decl kind");
6581 break;
6582 }
6583 }
6584
AddDeferredUnusedCoverageMapping(Decl * D)6585 void CodeGenModule::AddDeferredUnusedCoverageMapping(Decl *D) {
6586 // Do we need to generate coverage mapping?
6587 if (!CodeGenOpts.CoverageMapping)
6588 return;
6589 switch (D->getKind()) {
6590 case Decl::CXXConversion:
6591 case Decl::CXXMethod:
6592 case Decl::Function:
6593 case Decl::ObjCMethod:
6594 case Decl::CXXConstructor:
6595 case Decl::CXXDestructor: {
6596 if (!cast<FunctionDecl>(D)->doesThisDeclarationHaveABody())
6597 break;
6598 SourceManager &SM = getContext().getSourceManager();
6599 if (LimitedCoverage && SM.getMainFileID() != SM.getFileID(D->getBeginLoc()))
6600 break;
6601 auto I = DeferredEmptyCoverageMappingDecls.find(D);
6602 if (I == DeferredEmptyCoverageMappingDecls.end())
6603 DeferredEmptyCoverageMappingDecls[D] = true;
6604 break;
6605 }
6606 default:
6607 break;
6608 };
6609 }
6610
ClearUnusedCoverageMapping(const Decl * D)6611 void CodeGenModule::ClearUnusedCoverageMapping(const Decl *D) {
6612 // Do we need to generate coverage mapping?
6613 if (!CodeGenOpts.CoverageMapping)
6614 return;
6615 if (const auto *Fn = dyn_cast<FunctionDecl>(D)) {
6616 if (Fn->isTemplateInstantiation())
6617 ClearUnusedCoverageMapping(Fn->getTemplateInstantiationPattern());
6618 }
6619 auto I = DeferredEmptyCoverageMappingDecls.find(D);
6620 if (I == DeferredEmptyCoverageMappingDecls.end())
6621 DeferredEmptyCoverageMappingDecls[D] = false;
6622 else
6623 I->second = false;
6624 }
6625
EmitDeferredUnusedCoverageMappings()6626 void CodeGenModule::EmitDeferredUnusedCoverageMappings() {
6627 // We call takeVector() here to avoid use-after-free.
6628 // FIXME: DeferredEmptyCoverageMappingDecls is getting mutated because
6629 // we deserialize function bodies to emit coverage info for them, and that
6630 // deserializes more declarations. How should we handle that case?
6631 for (const auto &Entry : DeferredEmptyCoverageMappingDecls.takeVector()) {
6632 if (!Entry.second)
6633 continue;
6634 const Decl *D = Entry.first;
6635 switch (D->getKind()) {
6636 case Decl::CXXConversion:
6637 case Decl::CXXMethod:
6638 case Decl::Function:
6639 case Decl::ObjCMethod: {
6640 CodeGenPGO PGO(*this);
6641 GlobalDecl GD(cast<FunctionDecl>(D));
6642 PGO.emitEmptyCounterMapping(D, getMangledName(GD),
6643 getFunctionLinkage(GD));
6644 break;
6645 }
6646 case Decl::CXXConstructor: {
6647 CodeGenPGO PGO(*this);
6648 GlobalDecl GD(cast<CXXConstructorDecl>(D), Ctor_Base);
6649 PGO.emitEmptyCounterMapping(D, getMangledName(GD),
6650 getFunctionLinkage(GD));
6651 break;
6652 }
6653 case Decl::CXXDestructor: {
6654 CodeGenPGO PGO(*this);
6655 GlobalDecl GD(cast<CXXDestructorDecl>(D), Dtor_Base);
6656 PGO.emitEmptyCounterMapping(D, getMangledName(GD),
6657 getFunctionLinkage(GD));
6658 break;
6659 }
6660 default:
6661 break;
6662 };
6663 }
6664 }
6665
EmitMainVoidAlias()6666 void CodeGenModule::EmitMainVoidAlias() {
6667 // In order to transition away from "__original_main" gracefully, emit an
6668 // alias for "main" in the no-argument case so that libc can detect when
6669 // new-style no-argument main is in used.
6670 if (llvm::Function *F = getModule().getFunction("main")) {
6671 if (!F->isDeclaration() && F->arg_size() == 0 && !F->isVarArg() &&
6672 F->getReturnType()->isIntegerTy(Context.getTargetInfo().getIntWidth())) {
6673 auto *GA = llvm::GlobalAlias::create("__main_void", F);
6674 GA->setVisibility(llvm::GlobalValue::HiddenVisibility);
6675 }
6676 }
6677 }
6678
6679 /// Turns the given pointer into a constant.
GetPointerConstant(llvm::LLVMContext & Context,const void * Ptr)6680 static llvm::Constant *GetPointerConstant(llvm::LLVMContext &Context,
6681 const void *Ptr) {
6682 uintptr_t PtrInt = reinterpret_cast<uintptr_t>(Ptr);
6683 llvm::Type *i64 = llvm::Type::getInt64Ty(Context);
6684 return llvm::ConstantInt::get(i64, PtrInt);
6685 }
6686
EmitGlobalDeclMetadata(CodeGenModule & CGM,llvm::NamedMDNode * & GlobalMetadata,GlobalDecl D,llvm::GlobalValue * Addr)6687 static void EmitGlobalDeclMetadata(CodeGenModule &CGM,
6688 llvm::NamedMDNode *&GlobalMetadata,
6689 GlobalDecl D,
6690 llvm::GlobalValue *Addr) {
6691 if (!GlobalMetadata)
6692 GlobalMetadata =
6693 CGM.getModule().getOrInsertNamedMetadata("clang.global.decl.ptrs");
6694
6695 // TODO: should we report variant information for ctors/dtors?
6696 llvm::Metadata *Ops[] = {llvm::ConstantAsMetadata::get(Addr),
6697 llvm::ConstantAsMetadata::get(GetPointerConstant(
6698 CGM.getLLVMContext(), D.getDecl()))};
6699 GlobalMetadata->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops));
6700 }
6701
CheckAndReplaceExternCIFuncs(llvm::GlobalValue * Elem,llvm::GlobalValue * CppFunc)6702 bool CodeGenModule::CheckAndReplaceExternCIFuncs(llvm::GlobalValue *Elem,
6703 llvm::GlobalValue *CppFunc) {
6704 // Store the list of ifuncs we need to replace uses in.
6705 llvm::SmallVector<llvm::GlobalIFunc *> IFuncs;
6706 // List of ConstantExprs that we should be able to delete when we're done
6707 // here.
6708 llvm::SmallVector<llvm::ConstantExpr *> CEs;
6709
6710 // It isn't valid to replace the extern-C ifuncs if all we find is itself!
6711 if (Elem == CppFunc)
6712 return false;
6713
6714 // First make sure that all users of this are ifuncs (or ifuncs via a
6715 // bitcast), and collect the list of ifuncs and CEs so we can work on them
6716 // later.
6717 for (llvm::User *User : Elem->users()) {
6718 // Users can either be a bitcast ConstExpr that is used by the ifuncs, OR an
6719 // ifunc directly. In any other case, just give up, as we don't know what we
6720 // could break by changing those.
6721 if (auto *ConstExpr = dyn_cast<llvm::ConstantExpr>(User)) {
6722 if (ConstExpr->getOpcode() != llvm::Instruction::BitCast)
6723 return false;
6724
6725 for (llvm::User *CEUser : ConstExpr->users()) {
6726 if (auto *IFunc = dyn_cast<llvm::GlobalIFunc>(CEUser)) {
6727 IFuncs.push_back(IFunc);
6728 } else {
6729 return false;
6730 }
6731 }
6732 CEs.push_back(ConstExpr);
6733 } else if (auto *IFunc = dyn_cast<llvm::GlobalIFunc>(User)) {
6734 IFuncs.push_back(IFunc);
6735 } else {
6736 // This user is one we don't know how to handle, so fail redirection. This
6737 // will result in an ifunc retaining a resolver name that will ultimately
6738 // fail to be resolved to a defined function.
6739 return false;
6740 }
6741 }
6742
6743 // Now we know this is a valid case where we can do this alias replacement, we
6744 // need to remove all of the references to Elem (and the bitcasts!) so we can
6745 // delete it.
6746 for (llvm::GlobalIFunc *IFunc : IFuncs)
6747 IFunc->setResolver(nullptr);
6748 for (llvm::ConstantExpr *ConstExpr : CEs)
6749 ConstExpr->destroyConstant();
6750
6751 // We should now be out of uses for the 'old' version of this function, so we
6752 // can erase it as well.
6753 Elem->eraseFromParent();
6754
6755 for (llvm::GlobalIFunc *IFunc : IFuncs) {
6756 // The type of the resolver is always just a function-type that returns the
6757 // type of the IFunc, so create that here. If the type of the actual
6758 // resolver doesn't match, it just gets bitcast to the right thing.
6759 auto *ResolverTy =
6760 llvm::FunctionType::get(IFunc->getType(), /*isVarArg*/ false);
6761 llvm::Constant *Resolver = GetOrCreateLLVMFunction(
6762 CppFunc->getName(), ResolverTy, {}, /*ForVTable*/ false);
6763 IFunc->setResolver(Resolver);
6764 }
6765 return true;
6766 }
6767
6768 /// For each function which is declared within an extern "C" region and marked
6769 /// as 'used', but has internal linkage, create an alias from the unmangled
6770 /// name to the mangled name if possible. People expect to be able to refer
6771 /// to such functions with an unmangled name from inline assembly within the
6772 /// same translation unit.
EmitStaticExternCAliases()6773 void CodeGenModule::EmitStaticExternCAliases() {
6774 if (!getTargetCodeGenInfo().shouldEmitStaticExternCAliases())
6775 return;
6776 for (auto &I : StaticExternCValues) {
6777 IdentifierInfo *Name = I.first;
6778 llvm::GlobalValue *Val = I.second;
6779
6780 // If Val is null, that implies there were multiple declarations that each
6781 // had a claim to the unmangled name. In this case, generation of the alias
6782 // is suppressed. See CodeGenModule::MaybeHandleStaticInExternC.
6783 if (!Val)
6784 break;
6785
6786 llvm::GlobalValue *ExistingElem =
6787 getModule().getNamedValue(Name->getName());
6788
6789 // If there is either not something already by this name, or we were able to
6790 // replace all uses from IFuncs, create the alias.
6791 if (!ExistingElem || CheckAndReplaceExternCIFuncs(ExistingElem, Val))
6792 addCompilerUsedGlobal(llvm::GlobalAlias::create(Name->getName(), Val));
6793 }
6794 }
6795
lookupRepresentativeDecl(StringRef MangledName,GlobalDecl & Result) const6796 bool CodeGenModule::lookupRepresentativeDecl(StringRef MangledName,
6797 GlobalDecl &Result) const {
6798 auto Res = Manglings.find(MangledName);
6799 if (Res == Manglings.end())
6800 return false;
6801 Result = Res->getValue();
6802 return true;
6803 }
6804
6805 /// Emits metadata nodes associating all the global values in the
6806 /// current module with the Decls they came from. This is useful for
6807 /// projects using IR gen as a subroutine.
6808 ///
6809 /// Since there's currently no way to associate an MDNode directly
6810 /// with an llvm::GlobalValue, we create a global named metadata
6811 /// with the name 'clang.global.decl.ptrs'.
EmitDeclMetadata()6812 void CodeGenModule::EmitDeclMetadata() {
6813 llvm::NamedMDNode *GlobalMetadata = nullptr;
6814
6815 for (auto &I : MangledDeclNames) {
6816 llvm::GlobalValue *Addr = getModule().getNamedValue(I.second);
6817 // Some mangled names don't necessarily have an associated GlobalValue
6818 // in this module, e.g. if we mangled it for DebugInfo.
6819 if (Addr)
6820 EmitGlobalDeclMetadata(*this, GlobalMetadata, I.first, Addr);
6821 }
6822 }
6823
6824 /// Emits metadata nodes for all the local variables in the current
6825 /// function.
EmitDeclMetadata()6826 void CodeGenFunction::EmitDeclMetadata() {
6827 if (LocalDeclMap.empty()) return;
6828
6829 llvm::LLVMContext &Context = getLLVMContext();
6830
6831 // Find the unique metadata ID for this name.
6832 unsigned DeclPtrKind = Context.getMDKindID("clang.decl.ptr");
6833
6834 llvm::NamedMDNode *GlobalMetadata = nullptr;
6835
6836 for (auto &I : LocalDeclMap) {
6837 const Decl *D = I.first;
6838 llvm::Value *Addr = I.second.getPointer();
6839 if (auto *Alloca = dyn_cast<llvm::AllocaInst>(Addr)) {
6840 llvm::Value *DAddr = GetPointerConstant(getLLVMContext(), D);
6841 Alloca->setMetadata(
6842 DeclPtrKind, llvm::MDNode::get(
6843 Context, llvm::ValueAsMetadata::getConstant(DAddr)));
6844 } else if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr)) {
6845 GlobalDecl GD = GlobalDecl(cast<VarDecl>(D));
6846 EmitGlobalDeclMetadata(CGM, GlobalMetadata, GD, GV);
6847 }
6848 }
6849 }
6850
EmitVersionIdentMetadata()6851 void CodeGenModule::EmitVersionIdentMetadata() {
6852 llvm::NamedMDNode *IdentMetadata =
6853 TheModule.getOrInsertNamedMetadata("llvm.ident");
6854 std::string Version = getClangFullVersion();
6855 llvm::LLVMContext &Ctx = TheModule.getContext();
6856
6857 llvm::Metadata *IdentNode[] = {llvm::MDString::get(Ctx, Version)};
6858 IdentMetadata->addOperand(llvm::MDNode::get(Ctx, IdentNode));
6859 }
6860
EmitCommandLineMetadata()6861 void CodeGenModule::EmitCommandLineMetadata() {
6862 llvm::NamedMDNode *CommandLineMetadata =
6863 TheModule.getOrInsertNamedMetadata("llvm.commandline");
6864 std::string CommandLine = getCodeGenOpts().RecordCommandLine;
6865 llvm::LLVMContext &Ctx = TheModule.getContext();
6866
6867 llvm::Metadata *CommandLineNode[] = {llvm::MDString::get(Ctx, CommandLine)};
6868 CommandLineMetadata->addOperand(llvm::MDNode::get(Ctx, CommandLineNode));
6869 }
6870
EmitCoverageFile()6871 void CodeGenModule::EmitCoverageFile() {
6872 if (getCodeGenOpts().CoverageDataFile.empty() &&
6873 getCodeGenOpts().CoverageNotesFile.empty())
6874 return;
6875
6876 llvm::NamedMDNode *CUNode = TheModule.getNamedMetadata("llvm.dbg.cu");
6877 if (!CUNode)
6878 return;
6879
6880 llvm::NamedMDNode *GCov = TheModule.getOrInsertNamedMetadata("llvm.gcov");
6881 llvm::LLVMContext &Ctx = TheModule.getContext();
6882 auto *CoverageDataFile =
6883 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageDataFile);
6884 auto *CoverageNotesFile =
6885 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageNotesFile);
6886 for (int i = 0, e = CUNode->getNumOperands(); i != e; ++i) {
6887 llvm::MDNode *CU = CUNode->getOperand(i);
6888 llvm::Metadata *Elts[] = {CoverageNotesFile, CoverageDataFile, CU};
6889 GCov->addOperand(llvm::MDNode::get(Ctx, Elts));
6890 }
6891 }
6892
GetAddrOfRTTIDescriptor(QualType Ty,bool ForEH)6893 llvm::Constant *CodeGenModule::GetAddrOfRTTIDescriptor(QualType Ty,
6894 bool ForEH) {
6895 // Return a bogus pointer if RTTI is disabled, unless it's for EH.
6896 // FIXME: should we even be calling this method if RTTI is disabled
6897 // and it's not for EH?
6898 if ((!ForEH && !getLangOpts().RTTI) || getLangOpts().CUDAIsDevice ||
6899 (getLangOpts().OpenMP && getLangOpts().OpenMPIsDevice &&
6900 getTriple().isNVPTX()))
6901 return llvm::Constant::getNullValue(Int8PtrTy);
6902
6903 if (ForEH && Ty->isObjCObjectPointerType() &&
6904 LangOpts.ObjCRuntime.isGNUFamily())
6905 return ObjCRuntime->GetEHType(Ty);
6906
6907 return getCXXABI().getAddrOfRTTIDescriptor(Ty);
6908 }
6909
EmitOMPThreadPrivateDecl(const OMPThreadPrivateDecl * D)6910 void CodeGenModule::EmitOMPThreadPrivateDecl(const OMPThreadPrivateDecl *D) {
6911 // Do not emit threadprivates in simd-only mode.
6912 if (LangOpts.OpenMP && LangOpts.OpenMPSimd)
6913 return;
6914 for (auto RefExpr : D->varlists()) {
6915 auto *VD = cast<VarDecl>(cast<DeclRefExpr>(RefExpr)->getDecl());
6916 bool PerformInit =
6917 VD->getAnyInitializer() &&
6918 !VD->getAnyInitializer()->isConstantInitializer(getContext(),
6919 /*ForRef=*/false);
6920
6921 Address Addr(GetAddrOfGlobalVar(VD),
6922 getTypes().ConvertTypeForMem(VD->getType()),
6923 getContext().getDeclAlign(VD));
6924 if (auto InitFunction = getOpenMPRuntime().emitThreadPrivateVarDefinition(
6925 VD, Addr, RefExpr->getBeginLoc(), PerformInit))
6926 CXXGlobalInits.push_back(InitFunction);
6927 }
6928 }
6929
6930 llvm::Metadata *
CreateMetadataIdentifierImpl(QualType T,MetadataTypeMap & Map,StringRef Suffix)6931 CodeGenModule::CreateMetadataIdentifierImpl(QualType T, MetadataTypeMap &Map,
6932 StringRef Suffix) {
6933 if (auto *FnType = T->getAs<FunctionProtoType>())
6934 T = getContext().getFunctionType(
6935 FnType->getReturnType(), FnType->getParamTypes(),
6936 FnType->getExtProtoInfo().withExceptionSpec(EST_None));
6937
6938 llvm::Metadata *&InternalId = Map[T.getCanonicalType()];
6939 if (InternalId)
6940 return InternalId;
6941
6942 if (isExternallyVisible(T->getLinkage())) {
6943 std::string OutName;
6944 llvm::raw_string_ostream Out(OutName);
6945 getCXXABI().getMangleContext().mangleTypeName(T, Out);
6946 Out << Suffix;
6947
6948 InternalId = llvm::MDString::get(getLLVMContext(), Out.str());
6949 } else {
6950 InternalId = llvm::MDNode::getDistinct(getLLVMContext(),
6951 llvm::ArrayRef<llvm::Metadata *>());
6952 }
6953
6954 return InternalId;
6955 }
6956
CreateMetadataIdentifierForType(QualType T)6957 llvm::Metadata *CodeGenModule::CreateMetadataIdentifierForType(QualType T) {
6958 return CreateMetadataIdentifierImpl(T, MetadataIdMap, "");
6959 }
6960
6961 llvm::Metadata *
CreateMetadataIdentifierForVirtualMemPtrType(QualType T)6962 CodeGenModule::CreateMetadataIdentifierForVirtualMemPtrType(QualType T) {
6963 return CreateMetadataIdentifierImpl(T, VirtualMetadataIdMap, ".virtual");
6964 }
6965
6966 // Generalize pointer types to a void pointer with the qualifiers of the
6967 // originally pointed-to type, e.g. 'const char *' and 'char * const *'
6968 // generalize to 'const void *' while 'char *' and 'const char **' generalize to
6969 // 'void *'.
GeneralizeType(ASTContext & Ctx,QualType Ty)6970 static QualType GeneralizeType(ASTContext &Ctx, QualType Ty) {
6971 if (!Ty->isPointerType())
6972 return Ty;
6973
6974 return Ctx.getPointerType(
6975 QualType(Ctx.VoidTy).withCVRQualifiers(
6976 Ty->getPointeeType().getCVRQualifiers()));
6977 }
6978
6979 // Apply type generalization to a FunctionType's return and argument types
GeneralizeFunctionType(ASTContext & Ctx,QualType Ty)6980 static QualType GeneralizeFunctionType(ASTContext &Ctx, QualType Ty) {
6981 if (auto *FnType = Ty->getAs<FunctionProtoType>()) {
6982 SmallVector<QualType, 8> GeneralizedParams;
6983 for (auto &Param : FnType->param_types())
6984 GeneralizedParams.push_back(GeneralizeType(Ctx, Param));
6985
6986 return Ctx.getFunctionType(
6987 GeneralizeType(Ctx, FnType->getReturnType()),
6988 GeneralizedParams, FnType->getExtProtoInfo());
6989 }
6990
6991 if (auto *FnType = Ty->getAs<FunctionNoProtoType>())
6992 return Ctx.getFunctionNoProtoType(
6993 GeneralizeType(Ctx, FnType->getReturnType()));
6994
6995 llvm_unreachable("Encountered unknown FunctionType");
6996 }
6997
CreateMetadataIdentifierGeneralized(QualType T)6998 llvm::Metadata *CodeGenModule::CreateMetadataIdentifierGeneralized(QualType T) {
6999 return CreateMetadataIdentifierImpl(GeneralizeFunctionType(getContext(), T),
7000 GeneralizedMetadataIdMap, ".generalized");
7001 }
7002
7003 /// Returns whether this module needs the "all-vtables" type identifier.
NeedAllVtablesTypeId() const7004 bool CodeGenModule::NeedAllVtablesTypeId() const {
7005 // Returns true if at least one of vtable-based CFI checkers is enabled and
7006 // is not in the trapping mode.
7007 return ((LangOpts.Sanitize.has(SanitizerKind::CFIVCall) &&
7008 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIVCall)) ||
7009 (LangOpts.Sanitize.has(SanitizerKind::CFINVCall) &&
7010 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFINVCall)) ||
7011 (LangOpts.Sanitize.has(SanitizerKind::CFIDerivedCast) &&
7012 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIDerivedCast)) ||
7013 (LangOpts.Sanitize.has(SanitizerKind::CFIUnrelatedCast) &&
7014 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIUnrelatedCast)));
7015 }
7016
AddVTableTypeMetadata(llvm::GlobalVariable * VTable,CharUnits Offset,const CXXRecordDecl * RD)7017 void CodeGenModule::AddVTableTypeMetadata(llvm::GlobalVariable *VTable,
7018 CharUnits Offset,
7019 const CXXRecordDecl *RD) {
7020 llvm::Metadata *MD =
7021 CreateMetadataIdentifierForType(QualType(RD->getTypeForDecl(), 0));
7022 VTable->addTypeMetadata(Offset.getQuantity(), MD);
7023
7024 if (CodeGenOpts.SanitizeCfiCrossDso)
7025 if (auto CrossDsoTypeId = CreateCrossDsoCfiTypeId(MD))
7026 VTable->addTypeMetadata(Offset.getQuantity(),
7027 llvm::ConstantAsMetadata::get(CrossDsoTypeId));
7028
7029 if (NeedAllVtablesTypeId()) {
7030 llvm::Metadata *MD = llvm::MDString::get(getLLVMContext(), "all-vtables");
7031 VTable->addTypeMetadata(Offset.getQuantity(), MD);
7032 }
7033 }
7034
getSanStats()7035 llvm::SanitizerStatReport &CodeGenModule::getSanStats() {
7036 if (!SanStats)
7037 SanStats = std::make_unique<llvm::SanitizerStatReport>(&getModule());
7038
7039 return *SanStats;
7040 }
7041
7042 llvm::Value *
createOpenCLIntToSamplerConversion(const Expr * E,CodeGenFunction & CGF)7043 CodeGenModule::createOpenCLIntToSamplerConversion(const Expr *E,
7044 CodeGenFunction &CGF) {
7045 llvm::Constant *C = ConstantEmitter(CGF).emitAbstract(E, E->getType());
7046 auto *SamplerT = getOpenCLRuntime().getSamplerType(E->getType().getTypePtr());
7047 auto *FTy = llvm::FunctionType::get(SamplerT, {C->getType()}, false);
7048 auto *Call = CGF.EmitRuntimeCall(
7049 CreateRuntimeFunction(FTy, "__translate_sampler_initializer"), {C});
7050 return Call;
7051 }
7052
getNaturalPointeeTypeAlignment(QualType T,LValueBaseInfo * BaseInfo,TBAAAccessInfo * TBAAInfo)7053 CharUnits CodeGenModule::getNaturalPointeeTypeAlignment(
7054 QualType T, LValueBaseInfo *BaseInfo, TBAAAccessInfo *TBAAInfo) {
7055 return getNaturalTypeAlignment(T->getPointeeType(), BaseInfo, TBAAInfo,
7056 /* forPointeeType= */ true);
7057 }
7058
getNaturalTypeAlignment(QualType T,LValueBaseInfo * BaseInfo,TBAAAccessInfo * TBAAInfo,bool forPointeeType)7059 CharUnits CodeGenModule::getNaturalTypeAlignment(QualType T,
7060 LValueBaseInfo *BaseInfo,
7061 TBAAAccessInfo *TBAAInfo,
7062 bool forPointeeType) {
7063 if (TBAAInfo)
7064 *TBAAInfo = getTBAAAccessInfo(T);
7065
7066 // FIXME: This duplicates logic in ASTContext::getTypeAlignIfKnown. But
7067 // that doesn't return the information we need to compute BaseInfo.
7068
7069 // Honor alignment typedef attributes even on incomplete types.
7070 // We also honor them straight for C++ class types, even as pointees;
7071 // there's an expressivity gap here.
7072 if (auto TT = T->getAs<TypedefType>()) {
7073 if (auto Align = TT->getDecl()->getMaxAlignment()) {
7074 if (BaseInfo)
7075 *BaseInfo = LValueBaseInfo(AlignmentSource::AttributedType);
7076 return getContext().toCharUnitsFromBits(Align);
7077 }
7078 }
7079
7080 bool AlignForArray = T->isArrayType();
7081
7082 // Analyze the base element type, so we don't get confused by incomplete
7083 // array types.
7084 T = getContext().getBaseElementType(T);
7085
7086 if (T->isIncompleteType()) {
7087 // We could try to replicate the logic from
7088 // ASTContext::getTypeAlignIfKnown, but nothing uses the alignment if the
7089 // type is incomplete, so it's impossible to test. We could try to reuse
7090 // getTypeAlignIfKnown, but that doesn't return the information we need
7091 // to set BaseInfo. So just ignore the possibility that the alignment is
7092 // greater than one.
7093 if (BaseInfo)
7094 *BaseInfo = LValueBaseInfo(AlignmentSource::Type);
7095 return CharUnits::One();
7096 }
7097
7098 if (BaseInfo)
7099 *BaseInfo = LValueBaseInfo(AlignmentSource::Type);
7100
7101 CharUnits Alignment;
7102 const CXXRecordDecl *RD;
7103 if (T.getQualifiers().hasUnaligned()) {
7104 Alignment = CharUnits::One();
7105 } else if (forPointeeType && !AlignForArray &&
7106 (RD = T->getAsCXXRecordDecl())) {
7107 // For C++ class pointees, we don't know whether we're pointing at a
7108 // base or a complete object, so we generally need to use the
7109 // non-virtual alignment.
7110 Alignment = getClassPointerAlignment(RD);
7111 } else {
7112 Alignment = getContext().getTypeAlignInChars(T);
7113 }
7114
7115 // Cap to the global maximum type alignment unless the alignment
7116 // was somehow explicit on the type.
7117 if (unsigned MaxAlign = getLangOpts().MaxTypeAlign) {
7118 if (Alignment.getQuantity() > MaxAlign &&
7119 !getContext().isAlignmentRequired(T))
7120 Alignment = CharUnits::fromQuantity(MaxAlign);
7121 }
7122 return Alignment;
7123 }
7124
stopAutoInit()7125 bool CodeGenModule::stopAutoInit() {
7126 unsigned StopAfter = getContext().getLangOpts().TrivialAutoVarInitStopAfter;
7127 if (StopAfter) {
7128 // This number is positive only when -ftrivial-auto-var-init-stop-after=* is
7129 // used
7130 if (NumAutoVarInit >= StopAfter) {
7131 return true;
7132 }
7133 if (!NumAutoVarInit) {
7134 unsigned DiagID = getDiags().getCustomDiagID(
7135 DiagnosticsEngine::Warning,
7136 "-ftrivial-auto-var-init-stop-after=%0 has been enabled to limit the "
7137 "number of times ftrivial-auto-var-init=%1 gets applied.");
7138 getDiags().Report(DiagID)
7139 << StopAfter
7140 << (getContext().getLangOpts().getTrivialAutoVarInit() ==
7141 LangOptions::TrivialAutoVarInitKind::Zero
7142 ? "zero"
7143 : "pattern");
7144 }
7145 ++NumAutoVarInit;
7146 }
7147 return false;
7148 }
7149
printPostfixForExternalizedDecl(llvm::raw_ostream & OS,const Decl * D) const7150 void CodeGenModule::printPostfixForExternalizedDecl(llvm::raw_ostream &OS,
7151 const Decl *D) const {
7152 // ptxas does not allow '.' in symbol names. On the other hand, HIP prefers
7153 // postfix beginning with '.' since the symbol name can be demangled.
7154 if (LangOpts.HIP)
7155 OS << (isa<VarDecl>(D) ? ".static." : ".intern.");
7156 else
7157 OS << (isa<VarDecl>(D) ? "__static__" : "__intern__");
7158
7159 // If the CUID is not specified we try to generate a unique postfix.
7160 if (getLangOpts().CUID.empty()) {
7161 SourceManager &SM = getContext().getSourceManager();
7162 PresumedLoc PLoc = SM.getPresumedLoc(D->getLocation());
7163 assert(PLoc.isValid() && "Source location is expected to be valid.");
7164
7165 // Get the hash of the user defined macros.
7166 llvm::MD5 Hash;
7167 llvm::MD5::MD5Result Result;
7168 for (const auto &Arg : PreprocessorOpts.Macros)
7169 Hash.update(Arg.first);
7170 Hash.final(Result);
7171
7172 // Get the UniqueID for the file containing the decl.
7173 llvm::sys::fs::UniqueID ID;
7174 if (auto EC = llvm::sys::fs::getUniqueID(PLoc.getFilename(), ID)) {
7175 PLoc = SM.getPresumedLoc(D->getLocation(), /*UseLineDirectives=*/false);
7176 assert(PLoc.isValid() && "Source location is expected to be valid.");
7177 if (auto EC = llvm::sys::fs::getUniqueID(PLoc.getFilename(), ID))
7178 SM.getDiagnostics().Report(diag::err_cannot_open_file)
7179 << PLoc.getFilename() << EC.message();
7180 }
7181 OS << llvm::format("%x", ID.getFile()) << llvm::format("%x", ID.getDevice())
7182 << "_" << llvm::utohexstr(Result.low(), /*LowerCase=*/true, /*Width=*/8);
7183 } else {
7184 OS << getContext().getCUIDHash();
7185 }
7186 }
7187
moveLazyEmissionStates(CodeGenModule * NewBuilder)7188 void CodeGenModule::moveLazyEmissionStates(CodeGenModule *NewBuilder) {
7189 assert(DeferredDeclsToEmit.empty() &&
7190 "Should have emitted all decls deferred to emit.");
7191 assert(NewBuilder->DeferredDecls.empty() &&
7192 "Newly created module should not have deferred decls");
7193 NewBuilder->DeferredDecls = std::move(DeferredDecls);
7194
7195 assert(NewBuilder->DeferredVTables.empty() &&
7196 "Newly created module should not have deferred vtables");
7197 NewBuilder->DeferredVTables = std::move(DeferredVTables);
7198
7199 assert(NewBuilder->MangledDeclNames.empty() &&
7200 "Newly created module should not have mangled decl names");
7201 assert(NewBuilder->Manglings.empty() &&
7202 "Newly created module should not have manglings");
7203 NewBuilder->Manglings = std::move(Manglings);
7204
7205 assert(WeakRefReferences.empty() && "Not all WeakRefRefs have been applied");
7206 NewBuilder->WeakRefReferences = std::move(WeakRefReferences);
7207
7208 NewBuilder->TBAA = std::move(TBAA);
7209
7210 assert(NewBuilder->EmittedDeferredDecls.empty() &&
7211 "Still have (unmerged) EmittedDeferredDecls deferred decls");
7212
7213 NewBuilder->EmittedDeferredDecls = std::move(EmittedDeferredDecls);
7214
7215 NewBuilder->ABI->MangleCtx = std::move(ABI->MangleCtx);
7216 }
7217