1 //===- MachineFunction.cpp ------------------------------------------------===//
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 // Collect native machine code information for a function. This allows
10 // target-specific information about the generated code to be stored with each
11 // function.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "llvm/CodeGen/MachineFunction.h"
16 #include "llvm/ADT/BitVector.h"
17 #include "llvm/ADT/DenseMap.h"
18 #include "llvm/ADT/DenseSet.h"
19 #include "llvm/ADT/STLExtras.h"
20 #include "llvm/ADT/SmallString.h"
21 #include "llvm/ADT/SmallVector.h"
22 #include "llvm/ADT/StringRef.h"
23 #include "llvm/ADT/Twine.h"
24 #include "llvm/Analysis/ConstantFolding.h"
25 #include "llvm/Analysis/EHPersonalities.h"
26 #include "llvm/CodeGen/MachineBasicBlock.h"
27 #include "llvm/CodeGen/MachineConstantPool.h"
28 #include "llvm/CodeGen/MachineFrameInfo.h"
29 #include "llvm/CodeGen/MachineInstr.h"
30 #include "llvm/CodeGen/MachineJumpTableInfo.h"
31 #include "llvm/CodeGen/MachineMemOperand.h"
32 #include "llvm/CodeGen/MachineModuleInfo.h"
33 #include "llvm/CodeGen/MachineRegisterInfo.h"
34 #include "llvm/CodeGen/PseudoSourceValue.h"
35 #include "llvm/CodeGen/TargetFrameLowering.h"
36 #include "llvm/CodeGen/TargetInstrInfo.h"
37 #include "llvm/CodeGen/TargetLowering.h"
38 #include "llvm/CodeGen/TargetRegisterInfo.h"
39 #include "llvm/CodeGen/TargetSubtargetInfo.h"
40 #include "llvm/CodeGen/WasmEHFuncInfo.h"
41 #include "llvm/CodeGen/WinEHFuncInfo.h"
42 #include "llvm/Config/llvm-config.h"
43 #include "llvm/IR/Attributes.h"
44 #include "llvm/IR/BasicBlock.h"
45 #include "llvm/IR/Constant.h"
46 #include "llvm/IR/DataLayout.h"
47 #include "llvm/IR/DebugInfoMetadata.h"
48 #include "llvm/IR/DerivedTypes.h"
49 #include "llvm/IR/Function.h"
50 #include "llvm/IR/GlobalValue.h"
51 #include "llvm/IR/Instruction.h"
52 #include "llvm/IR/Instructions.h"
53 #include "llvm/IR/Metadata.h"
54 #include "llvm/IR/Module.h"
55 #include "llvm/IR/ModuleSlotTracker.h"
56 #include "llvm/IR/Value.h"
57 #include "llvm/MC/MCContext.h"
58 #include "llvm/MC/MCSymbol.h"
59 #include "llvm/MC/SectionKind.h"
60 #include "llvm/Support/Casting.h"
61 #include "llvm/Support/CommandLine.h"
62 #include "llvm/Support/Compiler.h"
63 #include "llvm/Support/DOTGraphTraits.h"
64 #include "llvm/Support/Debug.h"
65 #include "llvm/Support/ErrorHandling.h"
66 #include "llvm/Support/GraphWriter.h"
67 #include "llvm/Support/raw_ostream.h"
68 #include "llvm/Target/TargetMachine.h"
69 #include <algorithm>
70 #include <cassert>
71 #include <cstddef>
72 #include <cstdint>
73 #include <iterator>
74 #include <string>
75 #include <type_traits>
76 #include <utility>
77 #include <vector>
78
79 using namespace llvm;
80
81 #define DEBUG_TYPE "codegen"
82
83 static cl::opt<unsigned> AlignAllFunctions(
84 "align-all-functions",
85 cl::desc("Force the alignment of all functions in log2 format (e.g. 4 "
86 "means align on 16B boundaries)."),
87 cl::init(0), cl::Hidden);
88
getPropertyName(MachineFunctionProperties::Property Prop)89 static const char *getPropertyName(MachineFunctionProperties::Property Prop) {
90 using P = MachineFunctionProperties::Property;
91
92 switch(Prop) {
93 case P::FailedISel: return "FailedISel";
94 case P::IsSSA: return "IsSSA";
95 case P::Legalized: return "Legalized";
96 case P::NoPHIs: return "NoPHIs";
97 case P::NoVRegs: return "NoVRegs";
98 case P::RegBankSelected: return "RegBankSelected";
99 case P::Selected: return "Selected";
100 case P::TracksLiveness: return "TracksLiveness";
101 case P::TiedOpsRewritten: return "TiedOpsRewritten";
102 }
103 llvm_unreachable("Invalid machine function property");
104 }
105
106 // Pin the vtable to this file.
anchor()107 void MachineFunction::Delegate::anchor() {}
108
print(raw_ostream & OS) const109 void MachineFunctionProperties::print(raw_ostream &OS) const {
110 const char *Separator = "";
111 for (BitVector::size_type I = 0; I < Properties.size(); ++I) {
112 if (!Properties[I])
113 continue;
114 OS << Separator << getPropertyName(static_cast<Property>(I));
115 Separator = ", ";
116 }
117 }
118
119 //===----------------------------------------------------------------------===//
120 // MachineFunction implementation
121 //===----------------------------------------------------------------------===//
122
123 // Out-of-line virtual method.
124 MachineFunctionInfo::~MachineFunctionInfo() = default;
125
deleteNode(MachineBasicBlock * MBB)126 void ilist_alloc_traits<MachineBasicBlock>::deleteNode(MachineBasicBlock *MBB) {
127 MBB->getParent()->DeleteMachineBasicBlock(MBB);
128 }
129
getFnStackAlignment(const TargetSubtargetInfo * STI,const Function & F)130 static inline unsigned getFnStackAlignment(const TargetSubtargetInfo *STI,
131 const Function &F) {
132 if (F.hasFnAttribute(Attribute::StackAlignment))
133 return F.getFnStackAlignment();
134 return STI->getFrameLowering()->getStackAlign().value();
135 }
136
MachineFunction(Function & F,const LLVMTargetMachine & Target,const TargetSubtargetInfo & STI,unsigned FunctionNum,MachineModuleInfo & mmi)137 MachineFunction::MachineFunction(Function &F, const LLVMTargetMachine &Target,
138 const TargetSubtargetInfo &STI,
139 unsigned FunctionNum, MachineModuleInfo &mmi)
140 : F(F), Target(Target), STI(&STI), Ctx(mmi.getContext()), MMI(mmi) {
141 FunctionNumber = FunctionNum;
142 init();
143 }
144
handleInsertion(MachineInstr & MI)145 void MachineFunction::handleInsertion(MachineInstr &MI) {
146 if (TheDelegate)
147 TheDelegate->MF_HandleInsertion(MI);
148 }
149
handleRemoval(MachineInstr & MI)150 void MachineFunction::handleRemoval(MachineInstr &MI) {
151 if (TheDelegate)
152 TheDelegate->MF_HandleRemoval(MI);
153 }
154
init()155 void MachineFunction::init() {
156 // Assume the function starts in SSA form with correct liveness.
157 Properties.set(MachineFunctionProperties::Property::IsSSA);
158 Properties.set(MachineFunctionProperties::Property::TracksLiveness);
159 if (STI->getRegisterInfo())
160 RegInfo = new (Allocator) MachineRegisterInfo(this);
161 else
162 RegInfo = nullptr;
163
164 MFInfo = nullptr;
165 // We can realign the stack if the target supports it and the user hasn't
166 // explicitly asked us not to.
167 bool CanRealignSP = STI->getFrameLowering()->isStackRealignable() &&
168 !F.hasFnAttribute("no-realign-stack");
169 FrameInfo = new (Allocator) MachineFrameInfo(
170 getFnStackAlignment(STI, F), /*StackRealignable=*/CanRealignSP,
171 /*ForcedRealign=*/CanRealignSP &&
172 F.hasFnAttribute(Attribute::StackAlignment));
173
174 if (F.hasFnAttribute(Attribute::StackAlignment))
175 FrameInfo->ensureMaxAlignment(*F.getFnStackAlign());
176
177 ConstantPool = new (Allocator) MachineConstantPool(getDataLayout());
178 Alignment = STI->getTargetLowering()->getMinFunctionAlignment();
179
180 // FIXME: Shouldn't use pref alignment if explicit alignment is set on F.
181 // FIXME: Use Function::hasOptSize().
182 if (!F.hasFnAttribute(Attribute::OptimizeForSize))
183 Alignment = std::max(Alignment,
184 STI->getTargetLowering()->getPrefFunctionAlignment());
185
186 if (AlignAllFunctions)
187 Alignment = Align(1ULL << AlignAllFunctions);
188
189 JumpTableInfo = nullptr;
190
191 if (isFuncletEHPersonality(classifyEHPersonality(
192 F.hasPersonalityFn() ? F.getPersonalityFn() : nullptr))) {
193 WinEHInfo = new (Allocator) WinEHFuncInfo();
194 }
195
196 if (isScopedEHPersonality(classifyEHPersonality(
197 F.hasPersonalityFn() ? F.getPersonalityFn() : nullptr))) {
198 WasmEHInfo = new (Allocator) WasmEHFuncInfo();
199 }
200
201 assert(Target.isCompatibleDataLayout(getDataLayout()) &&
202 "Can't create a MachineFunction using a Module with a "
203 "Target-incompatible DataLayout attached\n");
204
205 PSVManager =
206 std::make_unique<PseudoSourceValueManager>(*(getSubtarget().
207 getInstrInfo()));
208 }
209
~MachineFunction()210 MachineFunction::~MachineFunction() {
211 clear();
212 }
213
clear()214 void MachineFunction::clear() {
215 Properties.reset();
216 // Don't call destructors on MachineInstr and MachineOperand. All of their
217 // memory comes from the BumpPtrAllocator which is about to be purged.
218 //
219 // Do call MachineBasicBlock destructors, it contains std::vectors.
220 for (iterator I = begin(), E = end(); I != E; I = BasicBlocks.erase(I))
221 I->Insts.clearAndLeakNodesUnsafely();
222 MBBNumbering.clear();
223
224 InstructionRecycler.clear(Allocator);
225 OperandRecycler.clear(Allocator);
226 BasicBlockRecycler.clear(Allocator);
227 CodeViewAnnotations.clear();
228 VariableDbgInfos.clear();
229 if (RegInfo) {
230 RegInfo->~MachineRegisterInfo();
231 Allocator.Deallocate(RegInfo);
232 }
233 if (MFInfo) {
234 MFInfo->~MachineFunctionInfo();
235 Allocator.Deallocate(MFInfo);
236 }
237
238 FrameInfo->~MachineFrameInfo();
239 Allocator.Deallocate(FrameInfo);
240
241 ConstantPool->~MachineConstantPool();
242 Allocator.Deallocate(ConstantPool);
243
244 if (JumpTableInfo) {
245 JumpTableInfo->~MachineJumpTableInfo();
246 Allocator.Deallocate(JumpTableInfo);
247 }
248
249 if (WinEHInfo) {
250 WinEHInfo->~WinEHFuncInfo();
251 Allocator.Deallocate(WinEHInfo);
252 }
253
254 if (WasmEHInfo) {
255 WasmEHInfo->~WasmEHFuncInfo();
256 Allocator.Deallocate(WasmEHInfo);
257 }
258 }
259
getDataLayout() const260 const DataLayout &MachineFunction::getDataLayout() const {
261 return F.getParent()->getDataLayout();
262 }
263
264 /// Get the JumpTableInfo for this function.
265 /// If it does not already exist, allocate one.
266 MachineJumpTableInfo *MachineFunction::
getOrCreateJumpTableInfo(unsigned EntryKind)267 getOrCreateJumpTableInfo(unsigned EntryKind) {
268 if (JumpTableInfo) return JumpTableInfo;
269
270 JumpTableInfo = new (Allocator)
271 MachineJumpTableInfo((MachineJumpTableInfo::JTEntryKind)EntryKind);
272 return JumpTableInfo;
273 }
274
getDenormalMode(const fltSemantics & FPType) const275 DenormalMode MachineFunction::getDenormalMode(const fltSemantics &FPType) const {
276 return F.getDenormalMode(FPType);
277 }
278
279 /// Should we be emitting segmented stack stuff for the function
shouldSplitStack() const280 bool MachineFunction::shouldSplitStack() const {
281 return getFunction().hasFnAttribute("split-stack");
282 }
283
284 LLVM_NODISCARD unsigned
addFrameInst(const MCCFIInstruction & Inst)285 MachineFunction::addFrameInst(const MCCFIInstruction &Inst) {
286 FrameInstructions.push_back(Inst);
287 return FrameInstructions.size() - 1;
288 }
289
290 /// This discards all of the MachineBasicBlock numbers and recomputes them.
291 /// This guarantees that the MBB numbers are sequential, dense, and match the
292 /// ordering of the blocks within the function. If a specific MachineBasicBlock
293 /// is specified, only that block and those after it are renumbered.
RenumberBlocks(MachineBasicBlock * MBB)294 void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) {
295 if (empty()) { MBBNumbering.clear(); return; }
296 MachineFunction::iterator MBBI, E = end();
297 if (MBB == nullptr)
298 MBBI = begin();
299 else
300 MBBI = MBB->getIterator();
301
302 // Figure out the block number this should have.
303 unsigned BlockNo = 0;
304 if (MBBI != begin())
305 BlockNo = std::prev(MBBI)->getNumber() + 1;
306
307 for (; MBBI != E; ++MBBI, ++BlockNo) {
308 if (MBBI->getNumber() != (int)BlockNo) {
309 // Remove use of the old number.
310 if (MBBI->getNumber() != -1) {
311 assert(MBBNumbering[MBBI->getNumber()] == &*MBBI &&
312 "MBB number mismatch!");
313 MBBNumbering[MBBI->getNumber()] = nullptr;
314 }
315
316 // If BlockNo is already taken, set that block's number to -1.
317 if (MBBNumbering[BlockNo])
318 MBBNumbering[BlockNo]->setNumber(-1);
319
320 MBBNumbering[BlockNo] = &*MBBI;
321 MBBI->setNumber(BlockNo);
322 }
323 }
324
325 // Okay, all the blocks are renumbered. If we have compactified the block
326 // numbering, shrink MBBNumbering now.
327 assert(BlockNo <= MBBNumbering.size() && "Mismatch!");
328 MBBNumbering.resize(BlockNo);
329 }
330
331 /// This method iterates over the basic blocks and assigns their IsBeginSection
332 /// and IsEndSection fields. This must be called after MBB layout is finalized
333 /// and the SectionID's are assigned to MBBs.
assignBeginEndSections()334 void MachineFunction::assignBeginEndSections() {
335 front().setIsBeginSection();
336 auto CurrentSectionID = front().getSectionID();
337 for (auto MBBI = std::next(begin()), E = end(); MBBI != E; ++MBBI) {
338 if (MBBI->getSectionID() == CurrentSectionID)
339 continue;
340 MBBI->setIsBeginSection();
341 std::prev(MBBI)->setIsEndSection();
342 CurrentSectionID = MBBI->getSectionID();
343 }
344 back().setIsEndSection();
345 }
346
347 /// Allocate a new MachineInstr. Use this instead of `new MachineInstr'.
CreateMachineInstr(const MCInstrDesc & MCID,const DebugLoc & DL,bool NoImplicit)348 MachineInstr *MachineFunction::CreateMachineInstr(const MCInstrDesc &MCID,
349 const DebugLoc &DL,
350 bool NoImplicit) {
351 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
352 MachineInstr(*this, MCID, DL, NoImplicit);
353 }
354
355 /// Create a new MachineInstr which is a copy of the 'Orig' instruction,
356 /// identical in all ways except the instruction has no parent, prev, or next.
357 MachineInstr *
CloneMachineInstr(const MachineInstr * Orig)358 MachineFunction::CloneMachineInstr(const MachineInstr *Orig) {
359 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
360 MachineInstr(*this, *Orig);
361 }
362
CloneMachineInstrBundle(MachineBasicBlock & MBB,MachineBasicBlock::iterator InsertBefore,const MachineInstr & Orig)363 MachineInstr &MachineFunction::CloneMachineInstrBundle(MachineBasicBlock &MBB,
364 MachineBasicBlock::iterator InsertBefore, const MachineInstr &Orig) {
365 MachineInstr *FirstClone = nullptr;
366 MachineBasicBlock::const_instr_iterator I = Orig.getIterator();
367 while (true) {
368 MachineInstr *Cloned = CloneMachineInstr(&*I);
369 MBB.insert(InsertBefore, Cloned);
370 if (FirstClone == nullptr) {
371 FirstClone = Cloned;
372 } else {
373 Cloned->bundleWithPred();
374 }
375
376 if (!I->isBundledWithSucc())
377 break;
378 ++I;
379 }
380 // Copy over call site info to the cloned instruction if needed. If Orig is in
381 // a bundle, copyCallSiteInfo takes care of finding the call instruction in
382 // the bundle.
383 if (Orig.shouldUpdateCallSiteInfo())
384 copyCallSiteInfo(&Orig, FirstClone);
385 return *FirstClone;
386 }
387
388 /// Delete the given MachineInstr.
389 ///
390 /// This function also serves as the MachineInstr destructor - the real
391 /// ~MachineInstr() destructor must be empty.
392 void
DeleteMachineInstr(MachineInstr * MI)393 MachineFunction::DeleteMachineInstr(MachineInstr *MI) {
394 // Verify that a call site info is at valid state. This assertion should
395 // be triggered during the implementation of support for the
396 // call site info of a new architecture. If the assertion is triggered,
397 // back trace will tell where to insert a call to updateCallSiteInfo().
398 assert((!MI->isCandidateForCallSiteEntry() ||
399 CallSitesInfo.find(MI) == CallSitesInfo.end()) &&
400 "Call site info was not updated!");
401 // Strip it for parts. The operand array and the MI object itself are
402 // independently recyclable.
403 if (MI->Operands)
404 deallocateOperandArray(MI->CapOperands, MI->Operands);
405 // Don't call ~MachineInstr() which must be trivial anyway because
406 // ~MachineFunction drops whole lists of MachineInstrs wihout calling their
407 // destructors.
408 InstructionRecycler.Deallocate(Allocator, MI);
409 }
410
411 /// Allocate a new MachineBasicBlock. Use this instead of
412 /// `new MachineBasicBlock'.
413 MachineBasicBlock *
CreateMachineBasicBlock(const BasicBlock * bb)414 MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) {
415 return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator))
416 MachineBasicBlock(*this, bb);
417 }
418
419 /// Delete the given MachineBasicBlock.
420 void
DeleteMachineBasicBlock(MachineBasicBlock * MBB)421 MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) {
422 assert(MBB->getParent() == this && "MBB parent mismatch!");
423 // Clean up any references to MBB in jump tables before deleting it.
424 if (JumpTableInfo)
425 JumpTableInfo->RemoveMBBFromJumpTables(MBB);
426 MBB->~MachineBasicBlock();
427 BasicBlockRecycler.Deallocate(Allocator, MBB);
428 }
429
getMachineMemOperand(MachinePointerInfo PtrInfo,MachineMemOperand::Flags f,uint64_t s,Align base_alignment,const AAMDNodes & AAInfo,const MDNode * Ranges,SyncScope::ID SSID,AtomicOrdering Ordering,AtomicOrdering FailureOrdering)430 MachineMemOperand *MachineFunction::getMachineMemOperand(
431 MachinePointerInfo PtrInfo, MachineMemOperand::Flags f, uint64_t s,
432 Align base_alignment, const AAMDNodes &AAInfo, const MDNode *Ranges,
433 SyncScope::ID SSID, AtomicOrdering Ordering,
434 AtomicOrdering FailureOrdering) {
435 return new (Allocator)
436 MachineMemOperand(PtrInfo, f, s, base_alignment, AAInfo, Ranges,
437 SSID, Ordering, FailureOrdering);
438 }
439
getMachineMemOperand(const MachineMemOperand * MMO,MachinePointerInfo & PtrInfo,uint64_t Size)440 MachineMemOperand *MachineFunction::getMachineMemOperand(
441 const MachineMemOperand *MMO, MachinePointerInfo &PtrInfo, uint64_t Size) {
442 return new (Allocator) MachineMemOperand(
443 PtrInfo, MMO->getFlags(), Size, MMO->getBaseAlign(), AAMDNodes(), nullptr,
444 MMO->getSyncScopeID(), MMO->getOrdering(), MMO->getFailureOrdering());
445 }
446
447 MachineMemOperand *
getMachineMemOperand(const MachineMemOperand * MMO,int64_t Offset,uint64_t Size)448 MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
449 int64_t Offset, uint64_t Size) {
450 const MachinePointerInfo &PtrInfo = MMO->getPointerInfo();
451
452 // If there is no pointer value, the offset isn't tracked so we need to adjust
453 // the base alignment.
454 Align Alignment = PtrInfo.V.isNull()
455 ? commonAlignment(MMO->getBaseAlign(), Offset)
456 : MMO->getBaseAlign();
457
458 // Do not preserve ranges, since we don't necessarily know what the high bits
459 // are anymore.
460 return new (Allocator)
461 MachineMemOperand(PtrInfo.getWithOffset(Offset), MMO->getFlags(), Size,
462 Alignment, MMO->getAAInfo(), nullptr, MMO->getSyncScopeID(),
463 MMO->getOrdering(), MMO->getFailureOrdering());
464 }
465
466 MachineMemOperand *
getMachineMemOperand(const MachineMemOperand * MMO,const AAMDNodes & AAInfo)467 MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
468 const AAMDNodes &AAInfo) {
469 MachinePointerInfo MPI = MMO->getValue() ?
470 MachinePointerInfo(MMO->getValue(), MMO->getOffset()) :
471 MachinePointerInfo(MMO->getPseudoValue(), MMO->getOffset());
472
473 return new (Allocator) MachineMemOperand(
474 MPI, MMO->getFlags(), MMO->getSize(), MMO->getBaseAlign(), AAInfo,
475 MMO->getRanges(), MMO->getSyncScopeID(), MMO->getOrdering(),
476 MMO->getFailureOrdering());
477 }
478
479 MachineMemOperand *
getMachineMemOperand(const MachineMemOperand * MMO,MachineMemOperand::Flags Flags)480 MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
481 MachineMemOperand::Flags Flags) {
482 return new (Allocator) MachineMemOperand(
483 MMO->getPointerInfo(), Flags, MMO->getSize(), MMO->getBaseAlign(),
484 MMO->getAAInfo(), MMO->getRanges(), MMO->getSyncScopeID(),
485 MMO->getOrdering(), MMO->getFailureOrdering());
486 }
487
createMIExtraInfo(ArrayRef<MachineMemOperand * > MMOs,MCSymbol * PreInstrSymbol,MCSymbol * PostInstrSymbol,MDNode * HeapAllocMarker)488 MachineInstr::ExtraInfo *MachineFunction::createMIExtraInfo(
489 ArrayRef<MachineMemOperand *> MMOs, MCSymbol *PreInstrSymbol,
490 MCSymbol *PostInstrSymbol, MDNode *HeapAllocMarker) {
491 return MachineInstr::ExtraInfo::create(Allocator, MMOs, PreInstrSymbol,
492 PostInstrSymbol, HeapAllocMarker);
493 }
494
createExternalSymbolName(StringRef Name)495 const char *MachineFunction::createExternalSymbolName(StringRef Name) {
496 char *Dest = Allocator.Allocate<char>(Name.size() + 1);
497 llvm::copy(Name, Dest);
498 Dest[Name.size()] = 0;
499 return Dest;
500 }
501
allocateRegMask()502 uint32_t *MachineFunction::allocateRegMask() {
503 unsigned NumRegs = getSubtarget().getRegisterInfo()->getNumRegs();
504 unsigned Size = MachineOperand::getRegMaskSize(NumRegs);
505 uint32_t *Mask = Allocator.Allocate<uint32_t>(Size);
506 memset(Mask, 0, Size * sizeof(Mask[0]));
507 return Mask;
508 }
509
allocateShuffleMask(ArrayRef<int> Mask)510 ArrayRef<int> MachineFunction::allocateShuffleMask(ArrayRef<int> Mask) {
511 int* AllocMask = Allocator.Allocate<int>(Mask.size());
512 copy(Mask, AllocMask);
513 return {AllocMask, Mask.size()};
514 }
515
516 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
dump() const517 LLVM_DUMP_METHOD void MachineFunction::dump() const {
518 print(dbgs());
519 }
520 #endif
521
getName() const522 StringRef MachineFunction::getName() const {
523 return getFunction().getName();
524 }
525
print(raw_ostream & OS,const SlotIndexes * Indexes) const526 void MachineFunction::print(raw_ostream &OS, const SlotIndexes *Indexes) const {
527 OS << "# Machine code for function " << getName() << ": ";
528 getProperties().print(OS);
529 OS << '\n';
530
531 // Print Frame Information
532 FrameInfo->print(*this, OS);
533
534 // Print JumpTable Information
535 if (JumpTableInfo)
536 JumpTableInfo->print(OS);
537
538 // Print Constant Pool
539 ConstantPool->print(OS);
540
541 const TargetRegisterInfo *TRI = getSubtarget().getRegisterInfo();
542
543 if (RegInfo && !RegInfo->livein_empty()) {
544 OS << "Function Live Ins: ";
545 for (MachineRegisterInfo::livein_iterator
546 I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) {
547 OS << printReg(I->first, TRI);
548 if (I->second)
549 OS << " in " << printReg(I->second, TRI);
550 if (std::next(I) != E)
551 OS << ", ";
552 }
553 OS << '\n';
554 }
555
556 ModuleSlotTracker MST(getFunction().getParent());
557 MST.incorporateFunction(getFunction());
558 for (const auto &BB : *this) {
559 OS << '\n';
560 // If we print the whole function, print it at its most verbose level.
561 BB.print(OS, MST, Indexes, /*IsStandalone=*/true);
562 }
563
564 OS << "\n# End machine code for function " << getName() << ".\n\n";
565 }
566
567 /// True if this function needs frame moves for debug or exceptions.
needsFrameMoves() const568 bool MachineFunction::needsFrameMoves() const {
569 return getMMI().hasDebugInfo() ||
570 getTarget().Options.ForceDwarfFrameSection ||
571 F.needsUnwindTableEntry();
572 }
573
574 namespace llvm {
575
576 template<>
577 struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits {
DOTGraphTraitsllvm::DOTGraphTraits578 DOTGraphTraits(bool isSimple = false) : DefaultDOTGraphTraits(isSimple) {}
579
getGraphNamellvm::DOTGraphTraits580 static std::string getGraphName(const MachineFunction *F) {
581 return ("CFG for '" + F->getName() + "' function").str();
582 }
583
getNodeLabelllvm::DOTGraphTraits584 std::string getNodeLabel(const MachineBasicBlock *Node,
585 const MachineFunction *Graph) {
586 std::string OutStr;
587 {
588 raw_string_ostream OSS(OutStr);
589
590 if (isSimple()) {
591 OSS << printMBBReference(*Node);
592 if (const BasicBlock *BB = Node->getBasicBlock())
593 OSS << ": " << BB->getName();
594 } else
595 Node->print(OSS);
596 }
597
598 if (OutStr[0] == '\n') OutStr.erase(OutStr.begin());
599
600 // Process string output to make it nicer...
601 for (unsigned i = 0; i != OutStr.length(); ++i)
602 if (OutStr[i] == '\n') { // Left justify
603 OutStr[i] = '\\';
604 OutStr.insert(OutStr.begin()+i+1, 'l');
605 }
606 return OutStr;
607 }
608 };
609
610 } // end namespace llvm
611
viewCFG() const612 void MachineFunction::viewCFG() const
613 {
614 #ifndef NDEBUG
615 ViewGraph(this, "mf" + getName());
616 #else
617 errs() << "MachineFunction::viewCFG is only available in debug builds on "
618 << "systems with Graphviz or gv!\n";
619 #endif // NDEBUG
620 }
621
viewCFGOnly() const622 void MachineFunction::viewCFGOnly() const
623 {
624 #ifndef NDEBUG
625 ViewGraph(this, "mf" + getName(), true);
626 #else
627 errs() << "MachineFunction::viewCFGOnly is only available in debug builds on "
628 << "systems with Graphviz or gv!\n";
629 #endif // NDEBUG
630 }
631
632 /// Add the specified physical register as a live-in value and
633 /// create a corresponding virtual register for it.
addLiveIn(MCRegister PReg,const TargetRegisterClass * RC)634 Register MachineFunction::addLiveIn(MCRegister PReg,
635 const TargetRegisterClass *RC) {
636 MachineRegisterInfo &MRI = getRegInfo();
637 Register VReg = MRI.getLiveInVirtReg(PReg);
638 if (VReg) {
639 const TargetRegisterClass *VRegRC = MRI.getRegClass(VReg);
640 (void)VRegRC;
641 // A physical register can be added several times.
642 // Between two calls, the register class of the related virtual register
643 // may have been constrained to match some operation constraints.
644 // In that case, check that the current register class includes the
645 // physical register and is a sub class of the specified RC.
646 assert((VRegRC == RC || (VRegRC->contains(PReg) &&
647 RC->hasSubClassEq(VRegRC))) &&
648 "Register class mismatch!");
649 return VReg;
650 }
651 VReg = MRI.createVirtualRegister(RC);
652 MRI.addLiveIn(PReg, VReg);
653 return VReg;
654 }
655
656 /// Return the MCSymbol for the specified non-empty jump table.
657 /// If isLinkerPrivate is specified, an 'l' label is returned, otherwise a
658 /// normal 'L' label is returned.
getJTISymbol(unsigned JTI,MCContext & Ctx,bool isLinkerPrivate) const659 MCSymbol *MachineFunction::getJTISymbol(unsigned JTI, MCContext &Ctx,
660 bool isLinkerPrivate) const {
661 const DataLayout &DL = getDataLayout();
662 assert(JumpTableInfo && "No jump tables");
663 assert(JTI < JumpTableInfo->getJumpTables().size() && "Invalid JTI!");
664
665 StringRef Prefix = isLinkerPrivate ? DL.getLinkerPrivateGlobalPrefix()
666 : DL.getPrivateGlobalPrefix();
667 SmallString<60> Name;
668 raw_svector_ostream(Name)
669 << Prefix << "JTI" << getFunctionNumber() << '_' << JTI;
670 return Ctx.getOrCreateSymbol(Name);
671 }
672
673 /// Return a function-local symbol to represent the PIC base.
getPICBaseSymbol() const674 MCSymbol *MachineFunction::getPICBaseSymbol() const {
675 const DataLayout &DL = getDataLayout();
676 return Ctx.getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
677 Twine(getFunctionNumber()) + "$pb");
678 }
679
680 /// \name Exception Handling
681 /// \{
682
683 LandingPadInfo &
getOrCreateLandingPadInfo(MachineBasicBlock * LandingPad)684 MachineFunction::getOrCreateLandingPadInfo(MachineBasicBlock *LandingPad) {
685 unsigned N = LandingPads.size();
686 for (unsigned i = 0; i < N; ++i) {
687 LandingPadInfo &LP = LandingPads[i];
688 if (LP.LandingPadBlock == LandingPad)
689 return LP;
690 }
691
692 LandingPads.push_back(LandingPadInfo(LandingPad));
693 return LandingPads[N];
694 }
695
addInvoke(MachineBasicBlock * LandingPad,MCSymbol * BeginLabel,MCSymbol * EndLabel)696 void MachineFunction::addInvoke(MachineBasicBlock *LandingPad,
697 MCSymbol *BeginLabel, MCSymbol *EndLabel) {
698 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
699 LP.BeginLabels.push_back(BeginLabel);
700 LP.EndLabels.push_back(EndLabel);
701 }
702
addLandingPad(MachineBasicBlock * LandingPad)703 MCSymbol *MachineFunction::addLandingPad(MachineBasicBlock *LandingPad) {
704 MCSymbol *LandingPadLabel = Ctx.createTempSymbol();
705 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
706 LP.LandingPadLabel = LandingPadLabel;
707
708 const Instruction *FirstI = LandingPad->getBasicBlock()->getFirstNonPHI();
709 if (const auto *LPI = dyn_cast<LandingPadInst>(FirstI)) {
710 if (const auto *PF =
711 dyn_cast<Function>(F.getPersonalityFn()->stripPointerCasts()))
712 getMMI().addPersonality(PF);
713
714 if (LPI->isCleanup())
715 addCleanup(LandingPad);
716
717 // FIXME: New EH - Add the clauses in reverse order. This isn't 100%
718 // correct, but we need to do it this way because of how the DWARF EH
719 // emitter processes the clauses.
720 for (unsigned I = LPI->getNumClauses(); I != 0; --I) {
721 Value *Val = LPI->getClause(I - 1);
722 if (LPI->isCatch(I - 1)) {
723 addCatchTypeInfo(LandingPad,
724 dyn_cast<GlobalValue>(Val->stripPointerCasts()));
725 } else {
726 // Add filters in a list.
727 auto *CVal = cast<Constant>(Val);
728 SmallVector<const GlobalValue *, 4> FilterList;
729 for (User::op_iterator II = CVal->op_begin(), IE = CVal->op_end();
730 II != IE; ++II)
731 FilterList.push_back(cast<GlobalValue>((*II)->stripPointerCasts()));
732
733 addFilterTypeInfo(LandingPad, FilterList);
734 }
735 }
736
737 } else if (const auto *CPI = dyn_cast<CatchPadInst>(FirstI)) {
738 for (unsigned I = CPI->getNumArgOperands(); I != 0; --I) {
739 Value *TypeInfo = CPI->getArgOperand(I - 1)->stripPointerCasts();
740 addCatchTypeInfo(LandingPad, dyn_cast<GlobalValue>(TypeInfo));
741 }
742
743 } else {
744 assert(isa<CleanupPadInst>(FirstI) && "Invalid landingpad!");
745 }
746
747 return LandingPadLabel;
748 }
749
addCatchTypeInfo(MachineBasicBlock * LandingPad,ArrayRef<const GlobalValue * > TyInfo)750 void MachineFunction::addCatchTypeInfo(MachineBasicBlock *LandingPad,
751 ArrayRef<const GlobalValue *> TyInfo) {
752 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
753 for (unsigned N = TyInfo.size(); N; --N)
754 LP.TypeIds.push_back(getTypeIDFor(TyInfo[N - 1]));
755 }
756
addFilterTypeInfo(MachineBasicBlock * LandingPad,ArrayRef<const GlobalValue * > TyInfo)757 void MachineFunction::addFilterTypeInfo(MachineBasicBlock *LandingPad,
758 ArrayRef<const GlobalValue *> TyInfo) {
759 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
760 std::vector<unsigned> IdsInFilter(TyInfo.size());
761 for (unsigned I = 0, E = TyInfo.size(); I != E; ++I)
762 IdsInFilter[I] = getTypeIDFor(TyInfo[I]);
763 LP.TypeIds.push_back(getFilterIDFor(IdsInFilter));
764 }
765
tidyLandingPads(DenseMap<MCSymbol *,uintptr_t> * LPMap,bool TidyIfNoBeginLabels)766 void MachineFunction::tidyLandingPads(DenseMap<MCSymbol *, uintptr_t> *LPMap,
767 bool TidyIfNoBeginLabels) {
768 for (unsigned i = 0; i != LandingPads.size(); ) {
769 LandingPadInfo &LandingPad = LandingPads[i];
770 if (LandingPad.LandingPadLabel &&
771 !LandingPad.LandingPadLabel->isDefined() &&
772 (!LPMap || (*LPMap)[LandingPad.LandingPadLabel] == 0))
773 LandingPad.LandingPadLabel = nullptr;
774
775 // Special case: we *should* emit LPs with null LP MBB. This indicates
776 // "nounwind" case.
777 if (!LandingPad.LandingPadLabel && LandingPad.LandingPadBlock) {
778 LandingPads.erase(LandingPads.begin() + i);
779 continue;
780 }
781
782 if (TidyIfNoBeginLabels) {
783 for (unsigned j = 0, e = LandingPads[i].BeginLabels.size(); j != e; ++j) {
784 MCSymbol *BeginLabel = LandingPad.BeginLabels[j];
785 MCSymbol *EndLabel = LandingPad.EndLabels[j];
786 if ((BeginLabel->isDefined() || (LPMap && (*LPMap)[BeginLabel] != 0)) &&
787 (EndLabel->isDefined() || (LPMap && (*LPMap)[EndLabel] != 0)))
788 continue;
789
790 LandingPad.BeginLabels.erase(LandingPad.BeginLabels.begin() + j);
791 LandingPad.EndLabels.erase(LandingPad.EndLabels.begin() + j);
792 --j;
793 --e;
794 }
795
796 // Remove landing pads with no try-ranges.
797 if (LandingPads[i].BeginLabels.empty()) {
798 LandingPads.erase(LandingPads.begin() + i);
799 continue;
800 }
801 }
802
803 // If there is no landing pad, ensure that the list of typeids is empty.
804 // If the only typeid is a cleanup, this is the same as having no typeids.
805 if (!LandingPad.LandingPadBlock ||
806 (LandingPad.TypeIds.size() == 1 && !LandingPad.TypeIds[0]))
807 LandingPad.TypeIds.clear();
808 ++i;
809 }
810 }
811
addCleanup(MachineBasicBlock * LandingPad)812 void MachineFunction::addCleanup(MachineBasicBlock *LandingPad) {
813 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
814 LP.TypeIds.push_back(0);
815 }
816
addSEHCatchHandler(MachineBasicBlock * LandingPad,const Function * Filter,const BlockAddress * RecoverBA)817 void MachineFunction::addSEHCatchHandler(MachineBasicBlock *LandingPad,
818 const Function *Filter,
819 const BlockAddress *RecoverBA) {
820 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
821 SEHHandler Handler;
822 Handler.FilterOrFinally = Filter;
823 Handler.RecoverBA = RecoverBA;
824 LP.SEHHandlers.push_back(Handler);
825 }
826
addSEHCleanupHandler(MachineBasicBlock * LandingPad,const Function * Cleanup)827 void MachineFunction::addSEHCleanupHandler(MachineBasicBlock *LandingPad,
828 const Function *Cleanup) {
829 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
830 SEHHandler Handler;
831 Handler.FilterOrFinally = Cleanup;
832 Handler.RecoverBA = nullptr;
833 LP.SEHHandlers.push_back(Handler);
834 }
835
setCallSiteLandingPad(MCSymbol * Sym,ArrayRef<unsigned> Sites)836 void MachineFunction::setCallSiteLandingPad(MCSymbol *Sym,
837 ArrayRef<unsigned> Sites) {
838 LPadToCallSiteMap[Sym].append(Sites.begin(), Sites.end());
839 }
840
getTypeIDFor(const GlobalValue * TI)841 unsigned MachineFunction::getTypeIDFor(const GlobalValue *TI) {
842 for (unsigned i = 0, N = TypeInfos.size(); i != N; ++i)
843 if (TypeInfos[i] == TI) return i + 1;
844
845 TypeInfos.push_back(TI);
846 return TypeInfos.size();
847 }
848
getFilterIDFor(std::vector<unsigned> & TyIds)849 int MachineFunction::getFilterIDFor(std::vector<unsigned> &TyIds) {
850 // If the new filter coincides with the tail of an existing filter, then
851 // re-use the existing filter. Folding filters more than this requires
852 // re-ordering filters and/or their elements - probably not worth it.
853 for (unsigned i : FilterEnds) {
854 unsigned j = TyIds.size();
855
856 while (i && j)
857 if (FilterIds[--i] != TyIds[--j])
858 goto try_next;
859
860 if (!j)
861 // The new filter coincides with range [i, end) of the existing filter.
862 return -(1 + i);
863
864 try_next:;
865 }
866
867 // Add the new filter.
868 int FilterID = -(1 + FilterIds.size());
869 FilterIds.reserve(FilterIds.size() + TyIds.size() + 1);
870 llvm::append_range(FilterIds, TyIds);
871 FilterEnds.push_back(FilterIds.size());
872 FilterIds.push_back(0); // terminator
873 return FilterID;
874 }
875
876 MachineFunction::CallSiteInfoMap::iterator
getCallSiteInfo(const MachineInstr * MI)877 MachineFunction::getCallSiteInfo(const MachineInstr *MI) {
878 assert(MI->isCandidateForCallSiteEntry() &&
879 "Call site info refers only to call (MI) candidates");
880
881 if (!Target.Options.EmitCallSiteInfo)
882 return CallSitesInfo.end();
883 return CallSitesInfo.find(MI);
884 }
885
886 /// Return the call machine instruction or find a call within bundle.
getCallInstr(const MachineInstr * MI)887 static const MachineInstr *getCallInstr(const MachineInstr *MI) {
888 if (!MI->isBundle())
889 return MI;
890
891 for (auto &BMI : make_range(getBundleStart(MI->getIterator()),
892 getBundleEnd(MI->getIterator())))
893 if (BMI.isCandidateForCallSiteEntry())
894 return &BMI;
895
896 llvm_unreachable("Unexpected bundle without a call site candidate");
897 }
898
eraseCallSiteInfo(const MachineInstr * MI)899 void MachineFunction::eraseCallSiteInfo(const MachineInstr *MI) {
900 assert(MI->shouldUpdateCallSiteInfo() &&
901 "Call site info refers only to call (MI) candidates or "
902 "candidates inside bundles");
903
904 const MachineInstr *CallMI = getCallInstr(MI);
905 CallSiteInfoMap::iterator CSIt = getCallSiteInfo(CallMI);
906 if (CSIt == CallSitesInfo.end())
907 return;
908 CallSitesInfo.erase(CSIt);
909 }
910
copyCallSiteInfo(const MachineInstr * Old,const MachineInstr * New)911 void MachineFunction::copyCallSiteInfo(const MachineInstr *Old,
912 const MachineInstr *New) {
913 assert(Old->shouldUpdateCallSiteInfo() &&
914 "Call site info refers only to call (MI) candidates or "
915 "candidates inside bundles");
916
917 if (!New->isCandidateForCallSiteEntry())
918 return eraseCallSiteInfo(Old);
919
920 const MachineInstr *OldCallMI = getCallInstr(Old);
921 CallSiteInfoMap::iterator CSIt = getCallSiteInfo(OldCallMI);
922 if (CSIt == CallSitesInfo.end())
923 return;
924
925 CallSiteInfo CSInfo = CSIt->second;
926 CallSitesInfo[New] = CSInfo;
927 }
928
moveCallSiteInfo(const MachineInstr * Old,const MachineInstr * New)929 void MachineFunction::moveCallSiteInfo(const MachineInstr *Old,
930 const MachineInstr *New) {
931 assert(Old->shouldUpdateCallSiteInfo() &&
932 "Call site info refers only to call (MI) candidates or "
933 "candidates inside bundles");
934
935 if (!New->isCandidateForCallSiteEntry())
936 return eraseCallSiteInfo(Old);
937
938 const MachineInstr *OldCallMI = getCallInstr(Old);
939 CallSiteInfoMap::iterator CSIt = getCallSiteInfo(OldCallMI);
940 if (CSIt == CallSitesInfo.end())
941 return;
942
943 CallSiteInfo CSInfo = std::move(CSIt->second);
944 CallSitesInfo.erase(CSIt);
945 CallSitesInfo[New] = CSInfo;
946 }
947
setDebugInstrNumberingCount(unsigned Num)948 void MachineFunction::setDebugInstrNumberingCount(unsigned Num) {
949 DebugInstrNumberingCount = Num;
950 }
951
makeDebugValueSubstitution(DebugInstrOperandPair A,DebugInstrOperandPair B)952 void MachineFunction::makeDebugValueSubstitution(DebugInstrOperandPair A,
953 DebugInstrOperandPair B) {
954 auto Result = DebugValueSubstitutions.insert(std::make_pair(A, B));
955 (void)Result;
956 assert(Result.second && "Substitution for an already substituted value?");
957 }
958
substituteDebugValuesForInst(const MachineInstr & Old,MachineInstr & New,unsigned MaxOperand)959 void MachineFunction::substituteDebugValuesForInst(const MachineInstr &Old,
960 MachineInstr &New,
961 unsigned MaxOperand) {
962 // If the Old instruction wasn't tracked at all, there is no work to do.
963 unsigned OldInstrNum = Old.peekDebugInstrNum();
964 if (!OldInstrNum)
965 return;
966
967 // Iterate over all operands looking for defs to create substitutions for.
968 // Avoid creating new instr numbers unless we create a new substitution.
969 // While this has no functional effect, it risks confusing someone reading
970 // MIR output.
971 // Examine all the operands, or the first N specified by the caller.
972 MaxOperand = std::min(MaxOperand, Old.getNumOperands());
973 for (unsigned int I = 0; I < Old.getNumOperands(); ++I) {
974 const auto &OldMO = Old.getOperand(I);
975 auto &NewMO = New.getOperand(I);
976 (void)NewMO;
977
978 if (!OldMO.isReg() || !OldMO.isDef())
979 continue;
980 assert(NewMO.isDef());
981
982 unsigned NewInstrNum = New.getDebugInstrNum();
983 makeDebugValueSubstitution(std::make_pair(OldInstrNum, I),
984 std::make_pair(NewInstrNum, I));
985 }
986 }
987
988 /// \}
989
990 //===----------------------------------------------------------------------===//
991 // MachineJumpTableInfo implementation
992 //===----------------------------------------------------------------------===//
993
994 /// Return the size of each entry in the jump table.
getEntrySize(const DataLayout & TD) const995 unsigned MachineJumpTableInfo::getEntrySize(const DataLayout &TD) const {
996 // The size of a jump table entry is 4 bytes unless the entry is just the
997 // address of a block, in which case it is the pointer size.
998 switch (getEntryKind()) {
999 case MachineJumpTableInfo::EK_BlockAddress:
1000 return TD.getPointerSize();
1001 case MachineJumpTableInfo::EK_GPRel64BlockAddress:
1002 return 8;
1003 case MachineJumpTableInfo::EK_GPRel32BlockAddress:
1004 case MachineJumpTableInfo::EK_LabelDifference32:
1005 case MachineJumpTableInfo::EK_Custom32:
1006 return 4;
1007 case MachineJumpTableInfo::EK_Inline:
1008 return 0;
1009 }
1010 llvm_unreachable("Unknown jump table encoding!");
1011 }
1012
1013 /// Return the alignment of each entry in the jump table.
getEntryAlignment(const DataLayout & TD) const1014 unsigned MachineJumpTableInfo::getEntryAlignment(const DataLayout &TD) const {
1015 // The alignment of a jump table entry is the alignment of int32 unless the
1016 // entry is just the address of a block, in which case it is the pointer
1017 // alignment.
1018 switch (getEntryKind()) {
1019 case MachineJumpTableInfo::EK_BlockAddress:
1020 return TD.getPointerABIAlignment(0).value();
1021 case MachineJumpTableInfo::EK_GPRel64BlockAddress:
1022 return TD.getABIIntegerTypeAlignment(64).value();
1023 case MachineJumpTableInfo::EK_GPRel32BlockAddress:
1024 case MachineJumpTableInfo::EK_LabelDifference32:
1025 case MachineJumpTableInfo::EK_Custom32:
1026 return TD.getABIIntegerTypeAlignment(32).value();
1027 case MachineJumpTableInfo::EK_Inline:
1028 return 1;
1029 }
1030 llvm_unreachable("Unknown jump table encoding!");
1031 }
1032
1033 /// Create a new jump table entry in the jump table info.
createJumpTableIndex(const std::vector<MachineBasicBlock * > & DestBBs)1034 unsigned MachineJumpTableInfo::createJumpTableIndex(
1035 const std::vector<MachineBasicBlock*> &DestBBs) {
1036 assert(!DestBBs.empty() && "Cannot create an empty jump table!");
1037 JumpTables.push_back(MachineJumpTableEntry(DestBBs));
1038 return JumpTables.size()-1;
1039 }
1040
1041 /// If Old is the target of any jump tables, update the jump tables to branch
1042 /// to New instead.
ReplaceMBBInJumpTables(MachineBasicBlock * Old,MachineBasicBlock * New)1043 bool MachineJumpTableInfo::ReplaceMBBInJumpTables(MachineBasicBlock *Old,
1044 MachineBasicBlock *New) {
1045 assert(Old != New && "Not making a change?");
1046 bool MadeChange = false;
1047 for (size_t i = 0, e = JumpTables.size(); i != e; ++i)
1048 ReplaceMBBInJumpTable(i, Old, New);
1049 return MadeChange;
1050 }
1051
1052 /// If MBB is present in any jump tables, remove it.
RemoveMBBFromJumpTables(MachineBasicBlock * MBB)1053 bool MachineJumpTableInfo::RemoveMBBFromJumpTables(MachineBasicBlock *MBB) {
1054 bool MadeChange = false;
1055 for (MachineJumpTableEntry &JTE : JumpTables) {
1056 auto removeBeginItr = std::remove(JTE.MBBs.begin(), JTE.MBBs.end(), MBB);
1057 MadeChange |= (removeBeginItr != JTE.MBBs.end());
1058 JTE.MBBs.erase(removeBeginItr, JTE.MBBs.end());
1059 }
1060 return MadeChange;
1061 }
1062
1063 /// If Old is a target of the jump tables, update the jump table to branch to
1064 /// New instead.
ReplaceMBBInJumpTable(unsigned Idx,MachineBasicBlock * Old,MachineBasicBlock * New)1065 bool MachineJumpTableInfo::ReplaceMBBInJumpTable(unsigned Idx,
1066 MachineBasicBlock *Old,
1067 MachineBasicBlock *New) {
1068 assert(Old != New && "Not making a change?");
1069 bool MadeChange = false;
1070 MachineJumpTableEntry &JTE = JumpTables[Idx];
1071 for (size_t j = 0, e = JTE.MBBs.size(); j != e; ++j)
1072 if (JTE.MBBs[j] == Old) {
1073 JTE.MBBs[j] = New;
1074 MadeChange = true;
1075 }
1076 return MadeChange;
1077 }
1078
print(raw_ostream & OS) const1079 void MachineJumpTableInfo::print(raw_ostream &OS) const {
1080 if (JumpTables.empty()) return;
1081
1082 OS << "Jump Tables:\n";
1083
1084 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) {
1085 OS << printJumpTableEntryReference(i) << ':';
1086 for (unsigned j = 0, f = JumpTables[i].MBBs.size(); j != f; ++j)
1087 OS << ' ' << printMBBReference(*JumpTables[i].MBBs[j]);
1088 if (i != e)
1089 OS << '\n';
1090 }
1091
1092 OS << '\n';
1093 }
1094
1095 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
dump() const1096 LLVM_DUMP_METHOD void MachineJumpTableInfo::dump() const { print(dbgs()); }
1097 #endif
1098
printJumpTableEntryReference(unsigned Idx)1099 Printable llvm::printJumpTableEntryReference(unsigned Idx) {
1100 return Printable([Idx](raw_ostream &OS) { OS << "%jump-table." << Idx; });
1101 }
1102
1103 //===----------------------------------------------------------------------===//
1104 // MachineConstantPool implementation
1105 //===----------------------------------------------------------------------===//
1106
anchor()1107 void MachineConstantPoolValue::anchor() {}
1108
getSizeInBytes(const DataLayout & DL) const1109 unsigned MachineConstantPoolValue::getSizeInBytes(const DataLayout &DL) const {
1110 return DL.getTypeAllocSize(Ty);
1111 }
1112
getSizeInBytes(const DataLayout & DL) const1113 unsigned MachineConstantPoolEntry::getSizeInBytes(const DataLayout &DL) const {
1114 if (isMachineConstantPoolEntry())
1115 return Val.MachineCPVal->getSizeInBytes(DL);
1116 return DL.getTypeAllocSize(Val.ConstVal->getType());
1117 }
1118
needsRelocation() const1119 bool MachineConstantPoolEntry::needsRelocation() const {
1120 if (isMachineConstantPoolEntry())
1121 return true;
1122 return Val.ConstVal->needsDynamicRelocation();
1123 }
1124
1125 SectionKind
getSectionKind(const DataLayout * DL) const1126 MachineConstantPoolEntry::getSectionKind(const DataLayout *DL) const {
1127 if (needsRelocation())
1128 return SectionKind::getReadOnlyWithRel();
1129 switch (getSizeInBytes(*DL)) {
1130 case 4:
1131 return SectionKind::getMergeableConst4();
1132 case 8:
1133 return SectionKind::getMergeableConst8();
1134 case 16:
1135 return SectionKind::getMergeableConst16();
1136 case 32:
1137 return SectionKind::getMergeableConst32();
1138 default:
1139 return SectionKind::getReadOnly();
1140 }
1141 }
1142
~MachineConstantPool()1143 MachineConstantPool::~MachineConstantPool() {
1144 // A constant may be a member of both Constants and MachineCPVsSharingEntries,
1145 // so keep track of which we've deleted to avoid double deletions.
1146 DenseSet<MachineConstantPoolValue*> Deleted;
1147 for (unsigned i = 0, e = Constants.size(); i != e; ++i)
1148 if (Constants[i].isMachineConstantPoolEntry()) {
1149 Deleted.insert(Constants[i].Val.MachineCPVal);
1150 delete Constants[i].Val.MachineCPVal;
1151 }
1152 for (MachineConstantPoolValue *CPV : MachineCPVsSharingEntries) {
1153 if (Deleted.count(CPV) == 0)
1154 delete CPV;
1155 }
1156 }
1157
1158 /// Test whether the given two constants can be allocated the same constant pool
1159 /// entry.
CanShareConstantPoolEntry(const Constant * A,const Constant * B,const DataLayout & DL)1160 static bool CanShareConstantPoolEntry(const Constant *A, const Constant *B,
1161 const DataLayout &DL) {
1162 // Handle the trivial case quickly.
1163 if (A == B) return true;
1164
1165 // If they have the same type but weren't the same constant, quickly
1166 // reject them.
1167 if (A->getType() == B->getType()) return false;
1168
1169 // We can't handle structs or arrays.
1170 if (isa<StructType>(A->getType()) || isa<ArrayType>(A->getType()) ||
1171 isa<StructType>(B->getType()) || isa<ArrayType>(B->getType()))
1172 return false;
1173
1174 // For now, only support constants with the same size.
1175 uint64_t StoreSize = DL.getTypeStoreSize(A->getType());
1176 if (StoreSize != DL.getTypeStoreSize(B->getType()) || StoreSize > 128)
1177 return false;
1178
1179 Type *IntTy = IntegerType::get(A->getContext(), StoreSize*8);
1180
1181 // Try constant folding a bitcast of both instructions to an integer. If we
1182 // get two identical ConstantInt's, then we are good to share them. We use
1183 // the constant folding APIs to do this so that we get the benefit of
1184 // DataLayout.
1185 if (isa<PointerType>(A->getType()))
1186 A = ConstantFoldCastOperand(Instruction::PtrToInt,
1187 const_cast<Constant *>(A), IntTy, DL);
1188 else if (A->getType() != IntTy)
1189 A = ConstantFoldCastOperand(Instruction::BitCast, const_cast<Constant *>(A),
1190 IntTy, DL);
1191 if (isa<PointerType>(B->getType()))
1192 B = ConstantFoldCastOperand(Instruction::PtrToInt,
1193 const_cast<Constant *>(B), IntTy, DL);
1194 else if (B->getType() != IntTy)
1195 B = ConstantFoldCastOperand(Instruction::BitCast, const_cast<Constant *>(B),
1196 IntTy, DL);
1197
1198 return A == B;
1199 }
1200
1201 /// Create a new entry in the constant pool or return an existing one.
1202 /// User must specify the log2 of the minimum required alignment for the object.
getConstantPoolIndex(const Constant * C,Align Alignment)1203 unsigned MachineConstantPool::getConstantPoolIndex(const Constant *C,
1204 Align Alignment) {
1205 if (Alignment > PoolAlignment) PoolAlignment = Alignment;
1206
1207 // Check to see if we already have this constant.
1208 //
1209 // FIXME, this could be made much more efficient for large constant pools.
1210 for (unsigned i = 0, e = Constants.size(); i != e; ++i)
1211 if (!Constants[i].isMachineConstantPoolEntry() &&
1212 CanShareConstantPoolEntry(Constants[i].Val.ConstVal, C, DL)) {
1213 if (Constants[i].getAlign() < Alignment)
1214 Constants[i].Alignment = Alignment;
1215 return i;
1216 }
1217
1218 Constants.push_back(MachineConstantPoolEntry(C, Alignment));
1219 return Constants.size()-1;
1220 }
1221
getConstantPoolIndex(MachineConstantPoolValue * V,Align Alignment)1222 unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V,
1223 Align Alignment) {
1224 if (Alignment > PoolAlignment) PoolAlignment = Alignment;
1225
1226 // Check to see if we already have this constant.
1227 //
1228 // FIXME, this could be made much more efficient for large constant pools.
1229 int Idx = V->getExistingMachineCPValue(this, Alignment);
1230 if (Idx != -1) {
1231 MachineCPVsSharingEntries.insert(V);
1232 return (unsigned)Idx;
1233 }
1234
1235 Constants.push_back(MachineConstantPoolEntry(V, Alignment));
1236 return Constants.size()-1;
1237 }
1238
print(raw_ostream & OS) const1239 void MachineConstantPool::print(raw_ostream &OS) const {
1240 if (Constants.empty()) return;
1241
1242 OS << "Constant Pool:\n";
1243 for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
1244 OS << " cp#" << i << ": ";
1245 if (Constants[i].isMachineConstantPoolEntry())
1246 Constants[i].Val.MachineCPVal->print(OS);
1247 else
1248 Constants[i].Val.ConstVal->printAsOperand(OS, /*PrintType=*/false);
1249 OS << ", align=" << Constants[i].getAlign().value();
1250 OS << "\n";
1251 }
1252 }
1253
1254 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
dump() const1255 LLVM_DUMP_METHOD void MachineConstantPool::dump() const { print(dbgs()); }
1256 #endif
1257