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 if (&FPType == &APFloat::IEEEsingle()) {
277 Attribute Attr = F.getFnAttribute("denormal-fp-math-f32");
278 StringRef Val = Attr.getValueAsString();
279 if (!Val.empty())
280 return parseDenormalFPAttribute(Val);
281
282 // If the f32 variant of the attribute isn't specified, try to use the
283 // generic one.
284 }
285
286 // TODO: Should probably avoid the connection to the IR and store directly
287 // in the MachineFunction.
288 Attribute Attr = F.getFnAttribute("denormal-fp-math");
289 return parseDenormalFPAttribute(Attr.getValueAsString());
290 }
291
292 /// Should we be emitting segmented stack stuff for the function
shouldSplitStack() const293 bool MachineFunction::shouldSplitStack() const {
294 return getFunction().hasFnAttribute("split-stack");
295 }
296
297 LLVM_NODISCARD unsigned
addFrameInst(const MCCFIInstruction & Inst)298 MachineFunction::addFrameInst(const MCCFIInstruction &Inst) {
299 FrameInstructions.push_back(Inst);
300 return FrameInstructions.size() - 1;
301 }
302
303 /// This discards all of the MachineBasicBlock numbers and recomputes them.
304 /// This guarantees that the MBB numbers are sequential, dense, and match the
305 /// ordering of the blocks within the function. If a specific MachineBasicBlock
306 /// is specified, only that block and those after it are renumbered.
RenumberBlocks(MachineBasicBlock * MBB)307 void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) {
308 if (empty()) { MBBNumbering.clear(); return; }
309 MachineFunction::iterator MBBI, E = end();
310 if (MBB == nullptr)
311 MBBI = begin();
312 else
313 MBBI = MBB->getIterator();
314
315 // Figure out the block number this should have.
316 unsigned BlockNo = 0;
317 if (MBBI != begin())
318 BlockNo = std::prev(MBBI)->getNumber() + 1;
319
320 for (; MBBI != E; ++MBBI, ++BlockNo) {
321 if (MBBI->getNumber() != (int)BlockNo) {
322 // Remove use of the old number.
323 if (MBBI->getNumber() != -1) {
324 assert(MBBNumbering[MBBI->getNumber()] == &*MBBI &&
325 "MBB number mismatch!");
326 MBBNumbering[MBBI->getNumber()] = nullptr;
327 }
328
329 // If BlockNo is already taken, set that block's number to -1.
330 if (MBBNumbering[BlockNo])
331 MBBNumbering[BlockNo]->setNumber(-1);
332
333 MBBNumbering[BlockNo] = &*MBBI;
334 MBBI->setNumber(BlockNo);
335 }
336 }
337
338 // Okay, all the blocks are renumbered. If we have compactified the block
339 // numbering, shrink MBBNumbering now.
340 assert(BlockNo <= MBBNumbering.size() && "Mismatch!");
341 MBBNumbering.resize(BlockNo);
342 }
343
344 /// This is used with -fbasic-block-sections or -fbasicblock-labels option.
345 /// A unary encoding of basic block labels is done to keep ".strtab" sizes
346 /// small.
createBBLabels()347 void MachineFunction::createBBLabels() {
348 const TargetInstrInfo *TII = getSubtarget().getInstrInfo();
349 this->BBSectionsSymbolPrefix.resize(getNumBlockIDs(), 'a');
350 for (auto MBBI = begin(), E = end(); MBBI != E; ++MBBI) {
351 assert(
352 (MBBI->getNumber() >= 0 && MBBI->getNumber() < (int)getNumBlockIDs()) &&
353 "BasicBlock number was out of range!");
354 // 'a' - Normal block.
355 // 'r' - Return block.
356 // 'l' - Landing Pad.
357 // 'L' - Return and landing pad.
358 bool isEHPad = MBBI->isEHPad();
359 bool isRetBlock = MBBI->isReturnBlock() && !TII->isTailCall(MBBI->back());
360 char type = 'a';
361 if (isEHPad && isRetBlock)
362 type = 'L';
363 else if (isEHPad)
364 type = 'l';
365 else if (isRetBlock)
366 type = 'r';
367 BBSectionsSymbolPrefix[MBBI->getNumber()] = type;
368 }
369 }
370
371 /// This method iterates over the basic blocks and assigns their IsBeginSection
372 /// and IsEndSection fields. This must be called after MBB layout is finalized
373 /// and the SectionID's are assigned to MBBs.
assignBeginEndSections()374 void MachineFunction::assignBeginEndSections() {
375 front().setIsBeginSection();
376 auto CurrentSectionID = front().getSectionID();
377 for (auto MBBI = std::next(begin()), E = end(); MBBI != E; ++MBBI) {
378 if (MBBI->getSectionID() == CurrentSectionID)
379 continue;
380 MBBI->setIsBeginSection();
381 std::prev(MBBI)->setIsEndSection();
382 CurrentSectionID = MBBI->getSectionID();
383 }
384 back().setIsEndSection();
385 }
386
387 /// Allocate a new MachineInstr. Use this instead of `new MachineInstr'.
CreateMachineInstr(const MCInstrDesc & MCID,const DebugLoc & DL,bool NoImp)388 MachineInstr *MachineFunction::CreateMachineInstr(const MCInstrDesc &MCID,
389 const DebugLoc &DL,
390 bool NoImp) {
391 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
392 MachineInstr(*this, MCID, DL, NoImp);
393 }
394
395 /// Create a new MachineInstr which is a copy of the 'Orig' instruction,
396 /// identical in all ways except the instruction has no parent, prev, or next.
397 MachineInstr *
CloneMachineInstr(const MachineInstr * Orig)398 MachineFunction::CloneMachineInstr(const MachineInstr *Orig) {
399 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
400 MachineInstr(*this, *Orig);
401 }
402
CloneMachineInstrBundle(MachineBasicBlock & MBB,MachineBasicBlock::iterator InsertBefore,const MachineInstr & Orig)403 MachineInstr &MachineFunction::CloneMachineInstrBundle(MachineBasicBlock &MBB,
404 MachineBasicBlock::iterator InsertBefore, const MachineInstr &Orig) {
405 MachineInstr *FirstClone = nullptr;
406 MachineBasicBlock::const_instr_iterator I = Orig.getIterator();
407 while (true) {
408 MachineInstr *Cloned = CloneMachineInstr(&*I);
409 MBB.insert(InsertBefore, Cloned);
410 if (FirstClone == nullptr) {
411 FirstClone = Cloned;
412 } else {
413 Cloned->bundleWithPred();
414 }
415
416 if (!I->isBundledWithSucc())
417 break;
418 ++I;
419 }
420 // Copy over call site info to the cloned instruction if needed. If Orig is in
421 // a bundle, copyCallSiteInfo takes care of finding the call instruction in
422 // the bundle.
423 if (Orig.shouldUpdateCallSiteInfo())
424 copyCallSiteInfo(&Orig, FirstClone);
425 return *FirstClone;
426 }
427
428 /// Delete the given MachineInstr.
429 ///
430 /// This function also serves as the MachineInstr destructor - the real
431 /// ~MachineInstr() destructor must be empty.
432 void
DeleteMachineInstr(MachineInstr * MI)433 MachineFunction::DeleteMachineInstr(MachineInstr *MI) {
434 // Verify that a call site info is at valid state. This assertion should
435 // be triggered during the implementation of support for the
436 // call site info of a new architecture. If the assertion is triggered,
437 // back trace will tell where to insert a call to updateCallSiteInfo().
438 assert((!MI->isCandidateForCallSiteEntry() ||
439 CallSitesInfo.find(MI) == CallSitesInfo.end()) &&
440 "Call site info was not updated!");
441 // Strip it for parts. The operand array and the MI object itself are
442 // independently recyclable.
443 if (MI->Operands)
444 deallocateOperandArray(MI->CapOperands, MI->Operands);
445 // Don't call ~MachineInstr() which must be trivial anyway because
446 // ~MachineFunction drops whole lists of MachineInstrs wihout calling their
447 // destructors.
448 InstructionRecycler.Deallocate(Allocator, MI);
449 }
450
451 /// Allocate a new MachineBasicBlock. Use this instead of
452 /// `new MachineBasicBlock'.
453 MachineBasicBlock *
CreateMachineBasicBlock(const BasicBlock * bb)454 MachineFunction::CreateMachineBasicBlock(const BasicBlock *bb) {
455 return new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator))
456 MachineBasicBlock(*this, bb);
457 }
458
459 /// Delete the given MachineBasicBlock.
460 void
DeleteMachineBasicBlock(MachineBasicBlock * MBB)461 MachineFunction::DeleteMachineBasicBlock(MachineBasicBlock *MBB) {
462 assert(MBB->getParent() == this && "MBB parent mismatch!");
463 MBB->~MachineBasicBlock();
464 BasicBlockRecycler.Deallocate(Allocator, MBB);
465 }
466
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)467 MachineMemOperand *MachineFunction::getMachineMemOperand(
468 MachinePointerInfo PtrInfo, MachineMemOperand::Flags f, uint64_t s,
469 Align base_alignment, const AAMDNodes &AAInfo, const MDNode *Ranges,
470 SyncScope::ID SSID, AtomicOrdering Ordering,
471 AtomicOrdering FailureOrdering) {
472 return new (Allocator)
473 MachineMemOperand(PtrInfo, f, s, base_alignment, AAInfo, Ranges,
474 SSID, Ordering, FailureOrdering);
475 }
476
477 MachineMemOperand *
getMachineMemOperand(const MachineMemOperand * MMO,int64_t Offset,uint64_t Size)478 MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
479 int64_t Offset, uint64_t Size) {
480 const MachinePointerInfo &PtrInfo = MMO->getPointerInfo();
481
482 // If there is no pointer value, the offset isn't tracked so we need to adjust
483 // the base alignment.
484 Align Alignment = PtrInfo.V.isNull()
485 ? commonAlignment(MMO->getBaseAlign(), Offset)
486 : MMO->getBaseAlign();
487
488 return new (Allocator)
489 MachineMemOperand(PtrInfo.getWithOffset(Offset), MMO->getFlags(), Size,
490 Alignment, AAMDNodes(), nullptr, MMO->getSyncScopeID(),
491 MMO->getOrdering(), MMO->getFailureOrdering());
492 }
493
494 MachineMemOperand *
getMachineMemOperand(const MachineMemOperand * MMO,const AAMDNodes & AAInfo)495 MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
496 const AAMDNodes &AAInfo) {
497 MachinePointerInfo MPI = MMO->getValue() ?
498 MachinePointerInfo(MMO->getValue(), MMO->getOffset()) :
499 MachinePointerInfo(MMO->getPseudoValue(), MMO->getOffset());
500
501 return new (Allocator) MachineMemOperand(
502 MPI, MMO->getFlags(), MMO->getSize(), MMO->getBaseAlign(), AAInfo,
503 MMO->getRanges(), MMO->getSyncScopeID(), MMO->getOrdering(),
504 MMO->getFailureOrdering());
505 }
506
507 MachineMemOperand *
getMachineMemOperand(const MachineMemOperand * MMO,MachineMemOperand::Flags Flags)508 MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
509 MachineMemOperand::Flags Flags) {
510 return new (Allocator) MachineMemOperand(
511 MMO->getPointerInfo(), Flags, MMO->getSize(), MMO->getBaseAlign(),
512 MMO->getAAInfo(), MMO->getRanges(), MMO->getSyncScopeID(),
513 MMO->getOrdering(), MMO->getFailureOrdering());
514 }
515
createMIExtraInfo(ArrayRef<MachineMemOperand * > MMOs,MCSymbol * PreInstrSymbol,MCSymbol * PostInstrSymbol,MDNode * HeapAllocMarker)516 MachineInstr::ExtraInfo *MachineFunction::createMIExtraInfo(
517 ArrayRef<MachineMemOperand *> MMOs, MCSymbol *PreInstrSymbol,
518 MCSymbol *PostInstrSymbol, MDNode *HeapAllocMarker) {
519 return MachineInstr::ExtraInfo::create(Allocator, MMOs, PreInstrSymbol,
520 PostInstrSymbol, HeapAllocMarker);
521 }
522
createExternalSymbolName(StringRef Name)523 const char *MachineFunction::createExternalSymbolName(StringRef Name) {
524 char *Dest = Allocator.Allocate<char>(Name.size() + 1);
525 llvm::copy(Name, Dest);
526 Dest[Name.size()] = 0;
527 return Dest;
528 }
529
allocateRegMask()530 uint32_t *MachineFunction::allocateRegMask() {
531 unsigned NumRegs = getSubtarget().getRegisterInfo()->getNumRegs();
532 unsigned Size = MachineOperand::getRegMaskSize(NumRegs);
533 uint32_t *Mask = Allocator.Allocate<uint32_t>(Size);
534 memset(Mask, 0, Size * sizeof(Mask[0]));
535 return Mask;
536 }
537
allocateShuffleMask(ArrayRef<int> Mask)538 ArrayRef<int> MachineFunction::allocateShuffleMask(ArrayRef<int> Mask) {
539 int* AllocMask = Allocator.Allocate<int>(Mask.size());
540 copy(Mask, AllocMask);
541 return {AllocMask, Mask.size()};
542 }
543
544 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
dump() const545 LLVM_DUMP_METHOD void MachineFunction::dump() const {
546 print(dbgs());
547 }
548 #endif
549
getName() const550 StringRef MachineFunction::getName() const {
551 return getFunction().getName();
552 }
553
print(raw_ostream & OS,const SlotIndexes * Indexes) const554 void MachineFunction::print(raw_ostream &OS, const SlotIndexes *Indexes) const {
555 OS << "# Machine code for function " << getName() << ": ";
556 getProperties().print(OS);
557 OS << '\n';
558
559 // Print Frame Information
560 FrameInfo->print(*this, OS);
561
562 // Print JumpTable Information
563 if (JumpTableInfo)
564 JumpTableInfo->print(OS);
565
566 // Print Constant Pool
567 ConstantPool->print(OS);
568
569 const TargetRegisterInfo *TRI = getSubtarget().getRegisterInfo();
570
571 if (RegInfo && !RegInfo->livein_empty()) {
572 OS << "Function Live Ins: ";
573 for (MachineRegisterInfo::livein_iterator
574 I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) {
575 OS << printReg(I->first, TRI);
576 if (I->second)
577 OS << " in " << printReg(I->second, TRI);
578 if (std::next(I) != E)
579 OS << ", ";
580 }
581 OS << '\n';
582 }
583
584 ModuleSlotTracker MST(getFunction().getParent());
585 MST.incorporateFunction(getFunction());
586 for (const auto &BB : *this) {
587 OS << '\n';
588 // If we print the whole function, print it at its most verbose level.
589 BB.print(OS, MST, Indexes, /*IsStandalone=*/true);
590 }
591
592 OS << "\n# End machine code for function " << getName() << ".\n\n";
593 }
594
595 /// True if this function needs frame moves for debug or exceptions.
needsFrameMoves() const596 bool MachineFunction::needsFrameMoves() const {
597 return getMMI().hasDebugInfo() ||
598 getTarget().Options.ForceDwarfFrameSection ||
599 F.needsUnwindTableEntry();
600 }
601
602 namespace llvm {
603
604 template<>
605 struct DOTGraphTraits<const MachineFunction*> : public DefaultDOTGraphTraits {
DOTGraphTraitsllvm::DOTGraphTraits606 DOTGraphTraits(bool isSimple = false) : DefaultDOTGraphTraits(isSimple) {}
607
getGraphNamellvm::DOTGraphTraits608 static std::string getGraphName(const MachineFunction *F) {
609 return ("CFG for '" + F->getName() + "' function").str();
610 }
611
getNodeLabelllvm::DOTGraphTraits612 std::string getNodeLabel(const MachineBasicBlock *Node,
613 const MachineFunction *Graph) {
614 std::string OutStr;
615 {
616 raw_string_ostream OSS(OutStr);
617
618 if (isSimple()) {
619 OSS << printMBBReference(*Node);
620 if (const BasicBlock *BB = Node->getBasicBlock())
621 OSS << ": " << BB->getName();
622 } else
623 Node->print(OSS);
624 }
625
626 if (OutStr[0] == '\n') OutStr.erase(OutStr.begin());
627
628 // Process string output to make it nicer...
629 for (unsigned i = 0; i != OutStr.length(); ++i)
630 if (OutStr[i] == '\n') { // Left justify
631 OutStr[i] = '\\';
632 OutStr.insert(OutStr.begin()+i+1, 'l');
633 }
634 return OutStr;
635 }
636 };
637
638 } // end namespace llvm
639
viewCFG() const640 void MachineFunction::viewCFG() const
641 {
642 #ifndef NDEBUG
643 ViewGraph(this, "mf" + getName());
644 #else
645 errs() << "MachineFunction::viewCFG is only available in debug builds on "
646 << "systems with Graphviz or gv!\n";
647 #endif // NDEBUG
648 }
649
viewCFGOnly() const650 void MachineFunction::viewCFGOnly() const
651 {
652 #ifndef NDEBUG
653 ViewGraph(this, "mf" + getName(), true);
654 #else
655 errs() << "MachineFunction::viewCFGOnly is only available in debug builds on "
656 << "systems with Graphviz or gv!\n";
657 #endif // NDEBUG
658 }
659
660 /// Add the specified physical register as a live-in value and
661 /// create a corresponding virtual register for it.
addLiveIn(MCRegister PReg,const TargetRegisterClass * RC)662 Register MachineFunction::addLiveIn(MCRegister PReg,
663 const TargetRegisterClass *RC) {
664 MachineRegisterInfo &MRI = getRegInfo();
665 Register VReg = MRI.getLiveInVirtReg(PReg);
666 if (VReg) {
667 const TargetRegisterClass *VRegRC = MRI.getRegClass(VReg);
668 (void)VRegRC;
669 // A physical register can be added several times.
670 // Between two calls, the register class of the related virtual register
671 // may have been constrained to match some operation constraints.
672 // In that case, check that the current register class includes the
673 // physical register and is a sub class of the specified RC.
674 assert((VRegRC == RC || (VRegRC->contains(PReg) &&
675 RC->hasSubClassEq(VRegRC))) &&
676 "Register class mismatch!");
677 return VReg;
678 }
679 VReg = MRI.createVirtualRegister(RC);
680 MRI.addLiveIn(PReg, VReg);
681 return VReg;
682 }
683
684 /// Return the MCSymbol for the specified non-empty jump table.
685 /// If isLinkerPrivate is specified, an 'l' label is returned, otherwise a
686 /// normal 'L' label is returned.
getJTISymbol(unsigned JTI,MCContext & Ctx,bool isLinkerPrivate) const687 MCSymbol *MachineFunction::getJTISymbol(unsigned JTI, MCContext &Ctx,
688 bool isLinkerPrivate) const {
689 const DataLayout &DL = getDataLayout();
690 assert(JumpTableInfo && "No jump tables");
691 assert(JTI < JumpTableInfo->getJumpTables().size() && "Invalid JTI!");
692
693 StringRef Prefix = isLinkerPrivate ? DL.getLinkerPrivateGlobalPrefix()
694 : DL.getPrivateGlobalPrefix();
695 SmallString<60> Name;
696 raw_svector_ostream(Name)
697 << Prefix << "JTI" << getFunctionNumber() << '_' << JTI;
698 return Ctx.getOrCreateSymbol(Name);
699 }
700
701 /// Return a function-local symbol to represent the PIC base.
getPICBaseSymbol() const702 MCSymbol *MachineFunction::getPICBaseSymbol() const {
703 const DataLayout &DL = getDataLayout();
704 return Ctx.getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
705 Twine(getFunctionNumber()) + "$pb");
706 }
707
708 /// \name Exception Handling
709 /// \{
710
711 LandingPadInfo &
getOrCreateLandingPadInfo(MachineBasicBlock * LandingPad)712 MachineFunction::getOrCreateLandingPadInfo(MachineBasicBlock *LandingPad) {
713 unsigned N = LandingPads.size();
714 for (unsigned i = 0; i < N; ++i) {
715 LandingPadInfo &LP = LandingPads[i];
716 if (LP.LandingPadBlock == LandingPad)
717 return LP;
718 }
719
720 LandingPads.push_back(LandingPadInfo(LandingPad));
721 return LandingPads[N];
722 }
723
addInvoke(MachineBasicBlock * LandingPad,MCSymbol * BeginLabel,MCSymbol * EndLabel)724 void MachineFunction::addInvoke(MachineBasicBlock *LandingPad,
725 MCSymbol *BeginLabel, MCSymbol *EndLabel) {
726 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
727 LP.BeginLabels.push_back(BeginLabel);
728 LP.EndLabels.push_back(EndLabel);
729 }
730
addLandingPad(MachineBasicBlock * LandingPad)731 MCSymbol *MachineFunction::addLandingPad(MachineBasicBlock *LandingPad) {
732 MCSymbol *LandingPadLabel = Ctx.createTempSymbol();
733 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
734 LP.LandingPadLabel = LandingPadLabel;
735
736 const Instruction *FirstI = LandingPad->getBasicBlock()->getFirstNonPHI();
737 if (const auto *LPI = dyn_cast<LandingPadInst>(FirstI)) {
738 if (const auto *PF =
739 dyn_cast<Function>(F.getPersonalityFn()->stripPointerCasts()))
740 getMMI().addPersonality(PF);
741
742 if (LPI->isCleanup())
743 addCleanup(LandingPad);
744
745 // FIXME: New EH - Add the clauses in reverse order. This isn't 100%
746 // correct, but we need to do it this way because of how the DWARF EH
747 // emitter processes the clauses.
748 for (unsigned I = LPI->getNumClauses(); I != 0; --I) {
749 Value *Val = LPI->getClause(I - 1);
750 if (LPI->isCatch(I - 1)) {
751 addCatchTypeInfo(LandingPad,
752 dyn_cast<GlobalValue>(Val->stripPointerCasts()));
753 } else {
754 // Add filters in a list.
755 auto *CVal = cast<Constant>(Val);
756 SmallVector<const GlobalValue *, 4> FilterList;
757 for (User::op_iterator II = CVal->op_begin(), IE = CVal->op_end();
758 II != IE; ++II)
759 FilterList.push_back(cast<GlobalValue>((*II)->stripPointerCasts()));
760
761 addFilterTypeInfo(LandingPad, FilterList);
762 }
763 }
764
765 } else if (const auto *CPI = dyn_cast<CatchPadInst>(FirstI)) {
766 for (unsigned I = CPI->getNumArgOperands(); I != 0; --I) {
767 Value *TypeInfo = CPI->getArgOperand(I - 1)->stripPointerCasts();
768 addCatchTypeInfo(LandingPad, dyn_cast<GlobalValue>(TypeInfo));
769 }
770
771 } else {
772 assert(isa<CleanupPadInst>(FirstI) && "Invalid landingpad!");
773 }
774
775 return LandingPadLabel;
776 }
777
addCatchTypeInfo(MachineBasicBlock * LandingPad,ArrayRef<const GlobalValue * > TyInfo)778 void MachineFunction::addCatchTypeInfo(MachineBasicBlock *LandingPad,
779 ArrayRef<const GlobalValue *> TyInfo) {
780 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
781 for (unsigned N = TyInfo.size(); N; --N)
782 LP.TypeIds.push_back(getTypeIDFor(TyInfo[N - 1]));
783 }
784
addFilterTypeInfo(MachineBasicBlock * LandingPad,ArrayRef<const GlobalValue * > TyInfo)785 void MachineFunction::addFilterTypeInfo(MachineBasicBlock *LandingPad,
786 ArrayRef<const GlobalValue *> TyInfo) {
787 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
788 std::vector<unsigned> IdsInFilter(TyInfo.size());
789 for (unsigned I = 0, E = TyInfo.size(); I != E; ++I)
790 IdsInFilter[I] = getTypeIDFor(TyInfo[I]);
791 LP.TypeIds.push_back(getFilterIDFor(IdsInFilter));
792 }
793
tidyLandingPads(DenseMap<MCSymbol *,uintptr_t> * LPMap,bool TidyIfNoBeginLabels)794 void MachineFunction::tidyLandingPads(DenseMap<MCSymbol *, uintptr_t> *LPMap,
795 bool TidyIfNoBeginLabels) {
796 for (unsigned i = 0; i != LandingPads.size(); ) {
797 LandingPadInfo &LandingPad = LandingPads[i];
798 if (LandingPad.LandingPadLabel &&
799 !LandingPad.LandingPadLabel->isDefined() &&
800 (!LPMap || (*LPMap)[LandingPad.LandingPadLabel] == 0))
801 LandingPad.LandingPadLabel = nullptr;
802
803 // Special case: we *should* emit LPs with null LP MBB. This indicates
804 // "nounwind" case.
805 if (!LandingPad.LandingPadLabel && LandingPad.LandingPadBlock) {
806 LandingPads.erase(LandingPads.begin() + i);
807 continue;
808 }
809
810 if (TidyIfNoBeginLabels) {
811 for (unsigned j = 0, e = LandingPads[i].BeginLabels.size(); j != e; ++j) {
812 MCSymbol *BeginLabel = LandingPad.BeginLabels[j];
813 MCSymbol *EndLabel = LandingPad.EndLabels[j];
814 if ((BeginLabel->isDefined() || (LPMap && (*LPMap)[BeginLabel] != 0)) &&
815 (EndLabel->isDefined() || (LPMap && (*LPMap)[EndLabel] != 0)))
816 continue;
817
818 LandingPad.BeginLabels.erase(LandingPad.BeginLabels.begin() + j);
819 LandingPad.EndLabels.erase(LandingPad.EndLabels.begin() + j);
820 --j;
821 --e;
822 }
823
824 // Remove landing pads with no try-ranges.
825 if (LandingPads[i].BeginLabels.empty()) {
826 LandingPads.erase(LandingPads.begin() + i);
827 continue;
828 }
829 }
830
831 // If there is no landing pad, ensure that the list of typeids is empty.
832 // If the only typeid is a cleanup, this is the same as having no typeids.
833 if (!LandingPad.LandingPadBlock ||
834 (LandingPad.TypeIds.size() == 1 && !LandingPad.TypeIds[0]))
835 LandingPad.TypeIds.clear();
836 ++i;
837 }
838 }
839
addCleanup(MachineBasicBlock * LandingPad)840 void MachineFunction::addCleanup(MachineBasicBlock *LandingPad) {
841 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
842 LP.TypeIds.push_back(0);
843 }
844
addSEHCatchHandler(MachineBasicBlock * LandingPad,const Function * Filter,const BlockAddress * RecoverBA)845 void MachineFunction::addSEHCatchHandler(MachineBasicBlock *LandingPad,
846 const Function *Filter,
847 const BlockAddress *RecoverBA) {
848 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
849 SEHHandler Handler;
850 Handler.FilterOrFinally = Filter;
851 Handler.RecoverBA = RecoverBA;
852 LP.SEHHandlers.push_back(Handler);
853 }
854
addSEHCleanupHandler(MachineBasicBlock * LandingPad,const Function * Cleanup)855 void MachineFunction::addSEHCleanupHandler(MachineBasicBlock *LandingPad,
856 const Function *Cleanup) {
857 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
858 SEHHandler Handler;
859 Handler.FilterOrFinally = Cleanup;
860 Handler.RecoverBA = nullptr;
861 LP.SEHHandlers.push_back(Handler);
862 }
863
setCallSiteLandingPad(MCSymbol * Sym,ArrayRef<unsigned> Sites)864 void MachineFunction::setCallSiteLandingPad(MCSymbol *Sym,
865 ArrayRef<unsigned> Sites) {
866 LPadToCallSiteMap[Sym].append(Sites.begin(), Sites.end());
867 }
868
getTypeIDFor(const GlobalValue * TI)869 unsigned MachineFunction::getTypeIDFor(const GlobalValue *TI) {
870 for (unsigned i = 0, N = TypeInfos.size(); i != N; ++i)
871 if (TypeInfos[i] == TI) return i + 1;
872
873 TypeInfos.push_back(TI);
874 return TypeInfos.size();
875 }
876
getFilterIDFor(std::vector<unsigned> & TyIds)877 int MachineFunction::getFilterIDFor(std::vector<unsigned> &TyIds) {
878 // If the new filter coincides with the tail of an existing filter, then
879 // re-use the existing filter. Folding filters more than this requires
880 // re-ordering filters and/or their elements - probably not worth it.
881 for (std::vector<unsigned>::iterator I = FilterEnds.begin(),
882 E = FilterEnds.end(); I != E; ++I) {
883 unsigned i = *I, j = TyIds.size();
884
885 while (i && j)
886 if (FilterIds[--i] != TyIds[--j])
887 goto try_next;
888
889 if (!j)
890 // The new filter coincides with range [i, end) of the existing filter.
891 return -(1 + i);
892
893 try_next:;
894 }
895
896 // Add the new filter.
897 int FilterID = -(1 + FilterIds.size());
898 FilterIds.reserve(FilterIds.size() + TyIds.size() + 1);
899 FilterIds.insert(FilterIds.end(), TyIds.begin(), TyIds.end());
900 FilterEnds.push_back(FilterIds.size());
901 FilterIds.push_back(0); // terminator
902 return FilterID;
903 }
904
905 MachineFunction::CallSiteInfoMap::iterator
getCallSiteInfo(const MachineInstr * MI)906 MachineFunction::getCallSiteInfo(const MachineInstr *MI) {
907 assert(MI->isCandidateForCallSiteEntry() &&
908 "Call site info refers only to call (MI) candidates");
909
910 if (!Target.Options.EmitCallSiteInfo)
911 return CallSitesInfo.end();
912 return CallSitesInfo.find(MI);
913 }
914
915 /// Return the call machine instruction or find a call within bundle.
getCallInstr(const MachineInstr * MI)916 static const MachineInstr *getCallInstr(const MachineInstr *MI) {
917 if (!MI->isBundle())
918 return MI;
919
920 for (auto &BMI : make_range(getBundleStart(MI->getIterator()),
921 getBundleEnd(MI->getIterator())))
922 if (BMI.isCandidateForCallSiteEntry())
923 return &BMI;
924
925 llvm_unreachable("Unexpected bundle without a call site candidate");
926 }
927
eraseCallSiteInfo(const MachineInstr * MI)928 void MachineFunction::eraseCallSiteInfo(const MachineInstr *MI) {
929 assert(MI->shouldUpdateCallSiteInfo() &&
930 "Call site info refers only to call (MI) candidates or "
931 "candidates inside bundles");
932
933 const MachineInstr *CallMI = getCallInstr(MI);
934 CallSiteInfoMap::iterator CSIt = getCallSiteInfo(CallMI);
935 if (CSIt == CallSitesInfo.end())
936 return;
937 CallSitesInfo.erase(CSIt);
938 }
939
copyCallSiteInfo(const MachineInstr * Old,const MachineInstr * New)940 void MachineFunction::copyCallSiteInfo(const MachineInstr *Old,
941 const MachineInstr *New) {
942 assert(Old->shouldUpdateCallSiteInfo() &&
943 "Call site info refers only to call (MI) candidates or "
944 "candidates inside bundles");
945
946 if (!New->isCandidateForCallSiteEntry())
947 return eraseCallSiteInfo(Old);
948
949 const MachineInstr *OldCallMI = getCallInstr(Old);
950 CallSiteInfoMap::iterator CSIt = getCallSiteInfo(OldCallMI);
951 if (CSIt == CallSitesInfo.end())
952 return;
953
954 CallSiteInfo CSInfo = CSIt->second;
955 CallSitesInfo[New] = CSInfo;
956 }
957
moveCallSiteInfo(const MachineInstr * Old,const MachineInstr * New)958 void MachineFunction::moveCallSiteInfo(const MachineInstr *Old,
959 const MachineInstr *New) {
960 assert(Old->shouldUpdateCallSiteInfo() &&
961 "Call site info refers only to call (MI) candidates or "
962 "candidates inside bundles");
963
964 if (!New->isCandidateForCallSiteEntry())
965 return eraseCallSiteInfo(Old);
966
967 const MachineInstr *OldCallMI = getCallInstr(Old);
968 CallSiteInfoMap::iterator CSIt = getCallSiteInfo(OldCallMI);
969 if (CSIt == CallSitesInfo.end())
970 return;
971
972 CallSiteInfo CSInfo = std::move(CSIt->second);
973 CallSitesInfo.erase(CSIt);
974 CallSitesInfo[New] = CSInfo;
975 }
976
977 /// \}
978
979 //===----------------------------------------------------------------------===//
980 // MachineJumpTableInfo implementation
981 //===----------------------------------------------------------------------===//
982
983 /// Return the size of each entry in the jump table.
getEntrySize(const DataLayout & TD) const984 unsigned MachineJumpTableInfo::getEntrySize(const DataLayout &TD) const {
985 // The size of a jump table entry is 4 bytes unless the entry is just the
986 // address of a block, in which case it is the pointer size.
987 switch (getEntryKind()) {
988 case MachineJumpTableInfo::EK_BlockAddress:
989 return TD.getPointerSize();
990 case MachineJumpTableInfo::EK_GPRel64BlockAddress:
991 return 8;
992 case MachineJumpTableInfo::EK_GPRel32BlockAddress:
993 case MachineJumpTableInfo::EK_LabelDifference32:
994 case MachineJumpTableInfo::EK_Custom32:
995 return 4;
996 case MachineJumpTableInfo::EK_Inline:
997 return 0;
998 }
999 llvm_unreachable("Unknown jump table encoding!");
1000 }
1001
1002 /// Return the alignment of each entry in the jump table.
getEntryAlignment(const DataLayout & TD) const1003 unsigned MachineJumpTableInfo::getEntryAlignment(const DataLayout &TD) const {
1004 // The alignment of a jump table entry is the alignment of int32 unless the
1005 // entry is just the address of a block, in which case it is the pointer
1006 // alignment.
1007 switch (getEntryKind()) {
1008 case MachineJumpTableInfo::EK_BlockAddress:
1009 return TD.getPointerABIAlignment(0).value();
1010 case MachineJumpTableInfo::EK_GPRel64BlockAddress:
1011 return TD.getABIIntegerTypeAlignment(64).value();
1012 case MachineJumpTableInfo::EK_GPRel32BlockAddress:
1013 case MachineJumpTableInfo::EK_LabelDifference32:
1014 case MachineJumpTableInfo::EK_Custom32:
1015 return TD.getABIIntegerTypeAlignment(32).value();
1016 case MachineJumpTableInfo::EK_Inline:
1017 return 1;
1018 }
1019 llvm_unreachable("Unknown jump table encoding!");
1020 }
1021
1022 /// Create a new jump table entry in the jump table info.
createJumpTableIndex(const std::vector<MachineBasicBlock * > & DestBBs)1023 unsigned MachineJumpTableInfo::createJumpTableIndex(
1024 const std::vector<MachineBasicBlock*> &DestBBs) {
1025 assert(!DestBBs.empty() && "Cannot create an empty jump table!");
1026 JumpTables.push_back(MachineJumpTableEntry(DestBBs));
1027 return JumpTables.size()-1;
1028 }
1029
1030 /// If Old is the target of any jump tables, update the jump tables to branch
1031 /// to New instead.
ReplaceMBBInJumpTables(MachineBasicBlock * Old,MachineBasicBlock * New)1032 bool MachineJumpTableInfo::ReplaceMBBInJumpTables(MachineBasicBlock *Old,
1033 MachineBasicBlock *New) {
1034 assert(Old != New && "Not making a change?");
1035 bool MadeChange = false;
1036 for (size_t i = 0, e = JumpTables.size(); i != e; ++i)
1037 ReplaceMBBInJumpTable(i, Old, New);
1038 return MadeChange;
1039 }
1040
1041 /// If Old is a target of the jump tables, update the jump table to branch to
1042 /// New instead.
ReplaceMBBInJumpTable(unsigned Idx,MachineBasicBlock * Old,MachineBasicBlock * New)1043 bool MachineJumpTableInfo::ReplaceMBBInJumpTable(unsigned Idx,
1044 MachineBasicBlock *Old,
1045 MachineBasicBlock *New) {
1046 assert(Old != New && "Not making a change?");
1047 bool MadeChange = false;
1048 MachineJumpTableEntry &JTE = JumpTables[Idx];
1049 for (size_t j = 0, e = JTE.MBBs.size(); j != e; ++j)
1050 if (JTE.MBBs[j] == Old) {
1051 JTE.MBBs[j] = New;
1052 MadeChange = true;
1053 }
1054 return MadeChange;
1055 }
1056
print(raw_ostream & OS) const1057 void MachineJumpTableInfo::print(raw_ostream &OS) const {
1058 if (JumpTables.empty()) return;
1059
1060 OS << "Jump Tables:\n";
1061
1062 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) {
1063 OS << printJumpTableEntryReference(i) << ':';
1064 for (unsigned j = 0, f = JumpTables[i].MBBs.size(); j != f; ++j)
1065 OS << ' ' << printMBBReference(*JumpTables[i].MBBs[j]);
1066 if (i != e)
1067 OS << '\n';
1068 }
1069
1070 OS << '\n';
1071 }
1072
1073 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
dump() const1074 LLVM_DUMP_METHOD void MachineJumpTableInfo::dump() const { print(dbgs()); }
1075 #endif
1076
printJumpTableEntryReference(unsigned Idx)1077 Printable llvm::printJumpTableEntryReference(unsigned Idx) {
1078 return Printable([Idx](raw_ostream &OS) { OS << "%jump-table." << Idx; });
1079 }
1080
1081 //===----------------------------------------------------------------------===//
1082 // MachineConstantPool implementation
1083 //===----------------------------------------------------------------------===//
1084
anchor()1085 void MachineConstantPoolValue::anchor() {}
1086
getType() const1087 Type *MachineConstantPoolEntry::getType() const {
1088 if (isMachineConstantPoolEntry())
1089 return Val.MachineCPVal->getType();
1090 return Val.ConstVal->getType();
1091 }
1092
needsRelocation() const1093 bool MachineConstantPoolEntry::needsRelocation() const {
1094 if (isMachineConstantPoolEntry())
1095 return true;
1096 return Val.ConstVal->needsRelocation();
1097 }
1098
1099 SectionKind
getSectionKind(const DataLayout * DL) const1100 MachineConstantPoolEntry::getSectionKind(const DataLayout *DL) const {
1101 if (needsRelocation())
1102 return SectionKind::getReadOnlyWithRel();
1103 switch (DL->getTypeAllocSize(getType())) {
1104 case 4:
1105 return SectionKind::getMergeableConst4();
1106 case 8:
1107 return SectionKind::getMergeableConst8();
1108 case 16:
1109 return SectionKind::getMergeableConst16();
1110 case 32:
1111 return SectionKind::getMergeableConst32();
1112 default:
1113 return SectionKind::getReadOnly();
1114 }
1115 }
1116
~MachineConstantPool()1117 MachineConstantPool::~MachineConstantPool() {
1118 // A constant may be a member of both Constants and MachineCPVsSharingEntries,
1119 // so keep track of which we've deleted to avoid double deletions.
1120 DenseSet<MachineConstantPoolValue*> Deleted;
1121 for (unsigned i = 0, e = Constants.size(); i != e; ++i)
1122 if (Constants[i].isMachineConstantPoolEntry()) {
1123 Deleted.insert(Constants[i].Val.MachineCPVal);
1124 delete Constants[i].Val.MachineCPVal;
1125 }
1126 for (DenseSet<MachineConstantPoolValue*>::iterator I =
1127 MachineCPVsSharingEntries.begin(), E = MachineCPVsSharingEntries.end();
1128 I != E; ++I) {
1129 if (Deleted.count(*I) == 0)
1130 delete *I;
1131 }
1132 }
1133
1134 /// Test whether the given two constants can be allocated the same constant pool
1135 /// entry.
CanShareConstantPoolEntry(const Constant * A,const Constant * B,const DataLayout & DL)1136 static bool CanShareConstantPoolEntry(const Constant *A, const Constant *B,
1137 const DataLayout &DL) {
1138 // Handle the trivial case quickly.
1139 if (A == B) return true;
1140
1141 // If they have the same type but weren't the same constant, quickly
1142 // reject them.
1143 if (A->getType() == B->getType()) return false;
1144
1145 // We can't handle structs or arrays.
1146 if (isa<StructType>(A->getType()) || isa<ArrayType>(A->getType()) ||
1147 isa<StructType>(B->getType()) || isa<ArrayType>(B->getType()))
1148 return false;
1149
1150 // For now, only support constants with the same size.
1151 uint64_t StoreSize = DL.getTypeStoreSize(A->getType());
1152 if (StoreSize != DL.getTypeStoreSize(B->getType()) || StoreSize > 128)
1153 return false;
1154
1155 Type *IntTy = IntegerType::get(A->getContext(), StoreSize*8);
1156
1157 // Try constant folding a bitcast of both instructions to an integer. If we
1158 // get two identical ConstantInt's, then we are good to share them. We use
1159 // the constant folding APIs to do this so that we get the benefit of
1160 // DataLayout.
1161 if (isa<PointerType>(A->getType()))
1162 A = ConstantFoldCastOperand(Instruction::PtrToInt,
1163 const_cast<Constant *>(A), IntTy, DL);
1164 else if (A->getType() != IntTy)
1165 A = ConstantFoldCastOperand(Instruction::BitCast, const_cast<Constant *>(A),
1166 IntTy, DL);
1167 if (isa<PointerType>(B->getType()))
1168 B = ConstantFoldCastOperand(Instruction::PtrToInt,
1169 const_cast<Constant *>(B), IntTy, DL);
1170 else if (B->getType() != IntTy)
1171 B = ConstantFoldCastOperand(Instruction::BitCast, const_cast<Constant *>(B),
1172 IntTy, DL);
1173
1174 return A == B;
1175 }
1176
1177 /// Create a new entry in the constant pool or return an existing one.
1178 /// User must specify the log2 of the minimum required alignment for the object.
getConstantPoolIndex(const Constant * C,Align Alignment)1179 unsigned MachineConstantPool::getConstantPoolIndex(const Constant *C,
1180 Align Alignment) {
1181 if (Alignment > PoolAlignment) PoolAlignment = Alignment;
1182
1183 // Check to see if we already have this constant.
1184 //
1185 // FIXME, this could be made much more efficient for large constant pools.
1186 for (unsigned i = 0, e = Constants.size(); i != e; ++i)
1187 if (!Constants[i].isMachineConstantPoolEntry() &&
1188 CanShareConstantPoolEntry(Constants[i].Val.ConstVal, C, DL)) {
1189 if (Constants[i].getAlign() < Alignment)
1190 Constants[i].Alignment = Alignment;
1191 return i;
1192 }
1193
1194 Constants.push_back(MachineConstantPoolEntry(C, Alignment));
1195 return Constants.size()-1;
1196 }
1197
getConstantPoolIndex(MachineConstantPoolValue * V,Align Alignment)1198 unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V,
1199 Align Alignment) {
1200 if (Alignment > PoolAlignment) PoolAlignment = Alignment;
1201
1202 // Check to see if we already have this constant.
1203 //
1204 // FIXME, this could be made much more efficient for large constant pools.
1205 int Idx = V->getExistingMachineCPValue(this, Alignment);
1206 if (Idx != -1) {
1207 MachineCPVsSharingEntries.insert(V);
1208 return (unsigned)Idx;
1209 }
1210
1211 Constants.push_back(MachineConstantPoolEntry(V, Alignment));
1212 return Constants.size()-1;
1213 }
1214
print(raw_ostream & OS) const1215 void MachineConstantPool::print(raw_ostream &OS) const {
1216 if (Constants.empty()) return;
1217
1218 OS << "Constant Pool:\n";
1219 for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
1220 OS << " cp#" << i << ": ";
1221 if (Constants[i].isMachineConstantPoolEntry())
1222 Constants[i].Val.MachineCPVal->print(OS);
1223 else
1224 Constants[i].Val.ConstVal->printAsOperand(OS, /*PrintType=*/false);
1225 OS << ", align=" << Constants[i].getAlign().value();
1226 OS << "\n";
1227 }
1228 }
1229
1230 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
dump() const1231 LLVM_DUMP_METHOD void MachineConstantPool::dump() const { print(dbgs()); }
1232 #endif
1233