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/ProfileSummaryInfo.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/PseudoSourceValueManager.h"
36#include "llvm/CodeGen/TargetFrameLowering.h"
37#include "llvm/CodeGen/TargetInstrInfo.h"
38#include "llvm/CodeGen/TargetLowering.h"
39#include "llvm/CodeGen/TargetRegisterInfo.h"
40#include "llvm/CodeGen/TargetSubtargetInfo.h"
41#include "llvm/CodeGen/WasmEHFuncInfo.h"
42#include "llvm/CodeGen/WinEHFuncInfo.h"
43#include "llvm/Config/llvm-config.h"
44#include "llvm/IR/Attributes.h"
45#include "llvm/IR/BasicBlock.h"
46#include "llvm/IR/Constant.h"
47#include "llvm/IR/DataLayout.h"
48#include "llvm/IR/DerivedTypes.h"
49#include "llvm/IR/EHPersonalities.h"
50#include "llvm/IR/Function.h"
51#include "llvm/IR/GlobalValue.h"
52#include "llvm/IR/Instruction.h"
53#include "llvm/IR/Instructions.h"
54#include "llvm/IR/Metadata.h"
55#include "llvm/IR/Module.h"
56#include "llvm/IR/ModuleSlotTracker.h"
57#include "llvm/IR/Value.h"
58#include "llvm/MC/MCContext.h"
59#include "llvm/MC/MCSymbol.h"
60#include "llvm/MC/SectionKind.h"
61#include "llvm/Support/Casting.h"
62#include "llvm/Support/CommandLine.h"
63#include "llvm/Support/Compiler.h"
64#include "llvm/Support/DOTGraphTraits.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 <utility>
76#include <vector>
77
78#include "LiveDebugValues/LiveDebugValues.h"
79
80using namespace llvm;
81
82#define DEBUG_TYPE "codegen"
83
84static cl::opt<unsigned> AlignAllFunctions(
85 "align-all-functions",
86 cl::desc("Force the alignment of all functions in log2 format (e.g. 4 "
87 "means align on 16B boundaries)."),
88 cl::init(Val: 0), cl::Hidden);
89
90static const char *getPropertyName(MachineFunctionProperties::Property Prop) {
91 using P = MachineFunctionProperties::Property;
92
93 // clang-format off
94 switch(Prop) {
95 case P::FailedISel: return "FailedISel";
96 case P::IsSSA: return "IsSSA";
97 case P::Legalized: return "Legalized";
98 case P::NoPHIs: return "NoPHIs";
99 case P::NoVRegs: return "NoVRegs";
100 case P::RegBankSelected: return "RegBankSelected";
101 case P::Selected: return "Selected";
102 case P::TracksLiveness: return "TracksLiveness";
103 case P::TiedOpsRewritten: return "TiedOpsRewritten";
104 case P::FailsVerification: return "FailsVerification";
105 case P::FailedRegAlloc: return "FailedRegAlloc";
106 case P::TracksDebugUserValues: return "TracksDebugUserValues";
107 }
108 // clang-format on
109 llvm_unreachable("Invalid machine function property");
110}
111
112void setUnsafeStackSize(const Function &F, MachineFrameInfo &FrameInfo) {
113 if (!F.hasFnAttribute(Kind: Attribute::SafeStack))
114 return;
115
116 auto *Existing =
117 dyn_cast_or_null<MDTuple>(Val: F.getMetadata(KindID: LLVMContext::MD_annotation));
118
119 if (!Existing || Existing->getNumOperands() != 2)
120 return;
121
122 auto *MetadataName = "unsafe-stack-size";
123 if (auto &N = Existing->getOperand(I: 0)) {
124 if (N.equalsStr(Str: MetadataName)) {
125 if (auto &Op = Existing->getOperand(I: 1)) {
126 auto Val = mdconst::extract<ConstantInt>(MD: Op)->getZExtValue();
127 FrameInfo.setUnsafeStackSize(Val);
128 }
129 }
130 }
131}
132
133// Pin the vtable to this file.
134void MachineFunction::Delegate::anchor() {}
135
136void MachineFunctionProperties::print(raw_ostream &OS) const {
137 const char *Separator = "";
138 for (BitVector::size_type I = 0; I < Properties.size(); ++I) {
139 if (!Properties[I])
140 continue;
141 OS << Separator << getPropertyName(Prop: static_cast<Property>(I));
142 Separator = ", ";
143 }
144}
145
146//===----------------------------------------------------------------------===//
147// MachineFunction implementation
148//===----------------------------------------------------------------------===//
149
150// Out-of-line virtual method.
151MachineFunctionInfo::~MachineFunctionInfo() = default;
152
153void ilist_alloc_traits<MachineBasicBlock>::deleteNode(MachineBasicBlock *MBB) {
154 MBB->getParent()->deleteMachineBasicBlock(MBB);
155}
156
157static inline Align getFnStackAlignment(const TargetSubtargetInfo &STI,
158 const Function &F) {
159 if (auto MA = F.getFnStackAlign())
160 return *MA;
161 return STI.getFrameLowering()->getStackAlign();
162}
163
164MachineFunction::MachineFunction(Function &F, const TargetMachine &Target,
165 const TargetSubtargetInfo &STI, MCContext &Ctx,
166 unsigned FunctionNum)
167 : F(F), Target(Target), STI(STI), Ctx(Ctx) {
168 FunctionNumber = FunctionNum;
169 init();
170}
171
172void MachineFunction::handleInsertion(MachineInstr &MI) {
173 if (TheDelegate)
174 TheDelegate->MF_HandleInsertion(MI);
175}
176
177void MachineFunction::handleRemoval(MachineInstr &MI) {
178 if (TheDelegate)
179 TheDelegate->MF_HandleRemoval(MI);
180}
181
182void MachineFunction::handleChangeDesc(MachineInstr &MI,
183 const MCInstrDesc &TID) {
184 if (TheDelegate)
185 TheDelegate->MF_HandleChangeDesc(MI, TID);
186}
187
188void MachineFunction::init() {
189 // Assume the function starts in SSA form with correct liveness.
190 Properties.setIsSSA();
191 Properties.setTracksLiveness();
192 RegInfo = new (Allocator) MachineRegisterInfo(this);
193
194 MFInfo = nullptr;
195
196 // We can realign the stack if the target supports it and the user hasn't
197 // explicitly asked us not to.
198 bool CanRealignSP = STI.getFrameLowering()->isStackRealignable() &&
199 !F.hasFnAttribute(Kind: "no-realign-stack");
200 bool ForceRealignSP = F.hasFnAttribute(Kind: Attribute::StackAlignment) ||
201 F.hasFnAttribute(Kind: "stackrealign");
202 FrameInfo = new (Allocator) MachineFrameInfo(
203 getFnStackAlignment(STI, F), /*StackRealignable=*/CanRealignSP,
204 /*ForcedRealign=*/ForceRealignSP && CanRealignSP);
205
206 setUnsafeStackSize(F, FrameInfo&: *FrameInfo);
207
208 if (F.hasFnAttribute(Kind: Attribute::StackAlignment))
209 FrameInfo->ensureMaxAlignment(Alignment: *F.getFnStackAlign());
210
211 ConstantPool = new (Allocator) MachineConstantPool(getDataLayout());
212 Alignment = STI.getTargetLowering()->getMinFunctionAlignment();
213
214 // -fsanitize=function and -fsanitize=kcfi instrument indirect function calls
215 // to load a type hash before the function label. Ensure functions are aligned
216 // by a least 4 to avoid unaligned access, which is especially important for
217 // -mno-unaligned-access.
218 if (F.hasMetadata(KindID: LLVMContext::MD_func_sanitize) ||
219 F.getMetadata(KindID: LLVMContext::MD_kcfi_type))
220 Alignment = std::max(a: Alignment, b: Align(4));
221
222 if (AlignAllFunctions)
223 Alignment = Align(1ULL << AlignAllFunctions);
224
225 JumpTableInfo = nullptr;
226
227 if (isFuncletEHPersonality(Pers: classifyEHPersonality(
228 Pers: F.hasPersonalityFn() ? F.getPersonalityFn() : nullptr))) {
229 WinEHInfo = new (Allocator) WinEHFuncInfo();
230 }
231
232 if (isScopedEHPersonality(Pers: classifyEHPersonality(
233 Pers: F.hasPersonalityFn() ? F.getPersonalityFn() : nullptr))) {
234 WasmEHInfo = new (Allocator) WasmEHFuncInfo();
235 }
236
237 assert(Target.isCompatibleDataLayout(getDataLayout()) &&
238 "Can't create a MachineFunction using a Module with a "
239 "Target-incompatible DataLayout attached\n");
240
241 PSVManager = std::make_unique<PseudoSourceValueManager>(args: getTarget());
242}
243
244void MachineFunction::initTargetMachineFunctionInfo(
245 const TargetSubtargetInfo &STI) {
246 assert(!MFInfo && "MachineFunctionInfo already set");
247 MFInfo = Target.createMachineFunctionInfo(Allocator, F, STI: &STI);
248}
249
250MachineFunction::~MachineFunction() {
251 clear();
252}
253
254void MachineFunction::clear() {
255 Properties.reset();
256
257 // Clear JumpTableInfo first. Otherwise, every MBB we delete would do a
258 // linear search over the jump table entries to find and erase itself.
259 if (JumpTableInfo) {
260 JumpTableInfo->~MachineJumpTableInfo();
261 Allocator.Deallocate(Ptr: JumpTableInfo);
262 JumpTableInfo = nullptr;
263 }
264
265 // Don't call destructors on MachineInstr and MachineOperand. All of their
266 // memory comes from the BumpPtrAllocator which is about to be purged.
267 //
268 // Do call MachineBasicBlock destructors, it contains std::vectors.
269 for (iterator I = begin(), E = end(); I != E; I = BasicBlocks.erase(where: I))
270 I->Insts.clearAndLeakNodesUnsafely();
271 MBBNumbering.clear();
272
273 InstructionRecycler.clear(Allocator);
274 OperandRecycler.clear(Allocator);
275 BasicBlockRecycler.clear(Allocator);
276 CodeViewAnnotations.clear();
277 VariableDbgInfos.clear();
278 if (RegInfo) {
279 RegInfo->~MachineRegisterInfo();
280 Allocator.Deallocate(Ptr: RegInfo);
281 }
282 if (MFInfo) {
283 MFInfo->~MachineFunctionInfo();
284 Allocator.Deallocate(Ptr: MFInfo);
285 }
286
287 FrameInfo->~MachineFrameInfo();
288 Allocator.Deallocate(Ptr: FrameInfo);
289
290 ConstantPool->~MachineConstantPool();
291 Allocator.Deallocate(Ptr: ConstantPool);
292
293 if (WinEHInfo) {
294 WinEHInfo->~WinEHFuncInfo();
295 Allocator.Deallocate(Ptr: WinEHInfo);
296 }
297
298 if (WasmEHInfo) {
299 WasmEHInfo->~WasmEHFuncInfo();
300 Allocator.Deallocate(Ptr: WasmEHInfo);
301 }
302}
303
304const DataLayout &MachineFunction::getDataLayout() const {
305 return F.getDataLayout();
306}
307
308/// Get the JumpTableInfo for this function.
309/// If it does not already exist, allocate one.
310MachineJumpTableInfo *MachineFunction::
311getOrCreateJumpTableInfo(unsigned EntryKind) {
312 if (JumpTableInfo) return JumpTableInfo;
313
314 JumpTableInfo = new (Allocator)
315 MachineJumpTableInfo((MachineJumpTableInfo::JTEntryKind)EntryKind);
316 return JumpTableInfo;
317}
318
319DenormalMode MachineFunction::getDenormalMode(const fltSemantics &FPType) const {
320 return F.getDenormalMode(FPType);
321}
322
323/// Should we be emitting segmented stack stuff for the function
324bool MachineFunction::shouldSplitStack() const {
325 return getFunction().hasFnAttribute(Kind: "split-stack");
326}
327
328Align MachineFunction::getPreferredAlignment() const {
329 Align PrefAlignment;
330
331 if (MaybeAlign A = F.getPreferredAlignment())
332 PrefAlignment = *A;
333 else if (!F.hasOptSize())
334 PrefAlignment = STI.getTargetLowering()->getPrefFunctionAlignment();
335 else
336 PrefAlignment = Align(1);
337
338 return std::max(a: PrefAlignment, b: getAlignment());
339}
340
341[[nodiscard]] unsigned
342MachineFunction::addFrameInst(const MCCFIInstruction &Inst) {
343 FrameInstructions.push_back(x: Inst);
344 return FrameInstructions.size() - 1;
345}
346
347/// This discards all of the MachineBasicBlock numbers and recomputes them.
348/// This guarantees that the MBB numbers are sequential, dense, and match the
349/// ordering of the blocks within the function. If a specific MachineBasicBlock
350/// is specified, only that block and those after it are renumbered.
351void MachineFunction::RenumberBlocks(MachineBasicBlock *MBB) {
352 if (empty()) { MBBNumbering.clear(); return; }
353 MachineFunction::iterator MBBI, E = end();
354 if (MBB == nullptr)
355 MBBI = begin();
356 else
357 MBBI = MBB->getIterator();
358
359 // Figure out the block number this should have.
360 unsigned BlockNo = 0;
361 if (MBBI != begin())
362 BlockNo = std::prev(x: MBBI)->getNumber() + 1;
363
364 for (; MBBI != E; ++MBBI, ++BlockNo) {
365 if (MBBI->getNumber() != (int)BlockNo) {
366 // Remove use of the old number.
367 if (MBBI->getNumber() != -1) {
368 assert(MBBNumbering[MBBI->getNumber()] == &*MBBI &&
369 "MBB number mismatch!");
370 MBBNumbering[MBBI->getNumber()] = nullptr;
371 }
372
373 // If BlockNo is already taken, set that block's number to -1.
374 if (MBBNumbering[BlockNo])
375 MBBNumbering[BlockNo]->setNumber(-1);
376
377 MBBNumbering[BlockNo] = &*MBBI;
378 MBBI->setNumber(BlockNo);
379 }
380 }
381
382 // Okay, all the blocks are renumbered. If we have compactified the block
383 // numbering, shrink MBBNumbering now.
384 assert(BlockNo <= MBBNumbering.size() && "Mismatch!");
385 MBBNumbering.resize(new_size: BlockNo);
386 MBBNumberingEpoch++;
387}
388
389int64_t MachineFunction::estimateFunctionSizeInBytes() {
390 const TargetInstrInfo &TII = *getSubtarget().getInstrInfo();
391 const Align FunctionAlignment = getAlignment();
392 MachineFunction::iterator MBBI = begin(), E = end();
393 /// Offset - Distance from the beginning of the function to the end
394 /// of the basic block.
395 int64_t Offset = 0;
396
397 for (; MBBI != E; ++MBBI) {
398 const Align Alignment = MBBI->getAlignment();
399 int64_t BlockSize = 0;
400
401 for (auto &MI : *MBBI) {
402 BlockSize += TII.getInstSizeInBytes(MI);
403 }
404
405 int64_t OffsetBB;
406 if (Alignment <= FunctionAlignment) {
407 OffsetBB = alignTo(Size: Offset, A: Alignment);
408 } else {
409 // The alignment of this MBB is larger than the function's alignment, so
410 // we can't tell whether or not it will insert nops. Assume that it will.
411 OffsetBB = alignTo(Size: Offset, A: Alignment) + Alignment.value() -
412 FunctionAlignment.value();
413 }
414 Offset = OffsetBB + BlockSize;
415 }
416
417 return Offset;
418}
419
420/// This method iterates over the basic blocks and assigns their IsBeginSection
421/// and IsEndSection fields. This must be called after MBB layout is finalized
422/// and the SectionID's are assigned to MBBs.
423void MachineFunction::assignBeginEndSections() {
424 front().setIsBeginSection();
425 auto CurrentSectionID = front().getSectionID();
426 for (auto MBBI = std::next(x: begin()), E = end(); MBBI != E; ++MBBI) {
427 if (MBBI->getSectionID() == CurrentSectionID)
428 continue;
429 MBBI->setIsBeginSection();
430 std::prev(x: MBBI)->setIsEndSection();
431 CurrentSectionID = MBBI->getSectionID();
432 }
433 back().setIsEndSection();
434}
435
436/// Allocate a new MachineInstr. Use this instead of `new MachineInstr'.
437MachineInstr *MachineFunction::CreateMachineInstr(const MCInstrDesc &MCID,
438 DebugLoc DL,
439 bool NoImplicit) {
440 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
441 MachineInstr(*this, MCID, std::move(DL), NoImplicit);
442}
443
444/// Create a new MachineInstr which is a copy of the 'Orig' instruction,
445/// identical in all ways except the instruction has no parent, prev, or next.
446MachineInstr *
447MachineFunction::CloneMachineInstr(const MachineInstr *Orig) {
448 return new (InstructionRecycler.Allocate<MachineInstr>(Allocator))
449 MachineInstr(*this, *Orig);
450}
451
452MachineInstr &MachineFunction::cloneMachineInstrBundle(
453 MachineBasicBlock &MBB, MachineBasicBlock::iterator InsertBefore,
454 const MachineInstr &Orig) {
455 MachineInstr *FirstClone = nullptr;
456 MachineBasicBlock::const_instr_iterator I = Orig.getIterator();
457 while (true) {
458 MachineInstr *Cloned = CloneMachineInstr(Orig: &*I);
459 MBB.insert(I: InsertBefore, MI: Cloned);
460 if (FirstClone == nullptr) {
461 FirstClone = Cloned;
462 } else {
463 Cloned->bundleWithPred();
464 }
465
466 if (!I->isBundledWithSucc())
467 break;
468 ++I;
469 }
470 // Copy over call info to the cloned instruction if needed. If Orig is in
471 // a bundle, copyAdditionalCallInfo takes care of finding the call instruction
472 // in the bundle.
473 if (Orig.shouldUpdateAdditionalCallInfo())
474 copyAdditionalCallInfo(Old: &Orig, New: FirstClone);
475 return *FirstClone;
476}
477
478/// Delete the given MachineInstr.
479///
480/// This function also serves as the MachineInstr destructor - the real
481/// ~MachineInstr() destructor must be empty.
482void MachineFunction::deleteMachineInstr(MachineInstr *MI) {
483 // Verify that a call site info is at valid state. This assertion should
484 // be triggered during the implementation of support for the
485 // call site info of a new architecture. If the assertion is triggered,
486 // back trace will tell where to insert a call to updateCallSiteInfo().
487 assert((!MI->isCandidateForAdditionalCallInfo() ||
488 !CallSitesInfo.contains(MI)) &&
489 "Call site info was not updated!");
490 // Verify that the "called globals" info is in a valid state.
491 assert((!MI->isCandidateForAdditionalCallInfo() ||
492 !CalledGlobalsInfo.contains(MI)) &&
493 "Called globals info was not updated!");
494 // Strip it for parts. The operand array and the MI object itself are
495 // independently recyclable.
496 if (MI->Operands)
497 deallocateOperandArray(Cap: MI->CapOperands, Array: MI->Operands);
498 // Don't call ~MachineInstr() which must be trivial anyway because
499 // ~MachineFunction drops whole lists of MachineInstrs wihout calling their
500 // destructors.
501 InstructionRecycler.Deallocate(Allocator, Element: MI);
502}
503
504/// Allocate a new MachineBasicBlock. Use this instead of
505/// `new MachineBasicBlock'.
506MachineBasicBlock *
507MachineFunction::CreateMachineBasicBlock(const BasicBlock *BB,
508 std::optional<UniqueBBID> BBID) {
509 MachineBasicBlock *MBB =
510 new (BasicBlockRecycler.Allocate<MachineBasicBlock>(Allocator))
511 MachineBasicBlock(*this, BB);
512 // Set BBID for `-basic-block-sections=list` and `-basic-block-address-map` to
513 // allow robust mapping of profiles to basic blocks.
514 if (Target.Options.BBAddrMap ||
515 Target.getBBSectionsType() == BasicBlockSection::List)
516 MBB->setBBID(BBID.has_value() ? *BBID : UniqueBBID{.BaseID: NextBBID++, .CloneID: 0});
517 return MBB;
518}
519
520/// Delete the given MachineBasicBlock.
521void MachineFunction::deleteMachineBasicBlock(MachineBasicBlock *MBB) {
522 assert(MBB->getParent() == this && "MBB parent mismatch!");
523 // Clean up any references to MBB in jump tables before deleting it.
524 if (JumpTableInfo)
525 JumpTableInfo->RemoveMBBFromJumpTables(MBB);
526 MBB->~MachineBasicBlock();
527 BasicBlockRecycler.Deallocate(Allocator, Element: MBB);
528}
529
530MachineMemOperand *MachineFunction::getMachineMemOperand(
531 MachinePointerInfo PtrInfo, MachineMemOperand::Flags F, LocationSize Size,
532 Align BaseAlignment, const AAMDNodes &AAInfo, const MDNode *Ranges,
533 SyncScope::ID SSID, AtomicOrdering Ordering,
534 AtomicOrdering FailureOrdering) {
535 assert((!Size.hasValue() ||
536 Size.getValue().getKnownMinValue() != ~UINT64_C(0)) &&
537 "Unexpected an unknown size to be represented using "
538 "LocationSize::beforeOrAfter()");
539 return new (Allocator)
540 MachineMemOperand(PtrInfo, F, Size, BaseAlignment, AAInfo, Ranges, SSID,
541 Ordering, FailureOrdering);
542}
543
544MachineMemOperand *MachineFunction::getMachineMemOperand(
545 MachinePointerInfo PtrInfo, MachineMemOperand::Flags f, LLT MemTy,
546 Align base_alignment, const AAMDNodes &AAInfo, const MDNode *Ranges,
547 SyncScope::ID SSID, AtomicOrdering Ordering,
548 AtomicOrdering FailureOrdering) {
549 return new (Allocator)
550 MachineMemOperand(PtrInfo, f, MemTy, base_alignment, AAInfo, Ranges, SSID,
551 Ordering, FailureOrdering);
552}
553
554MachineMemOperand *
555MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
556 const MachinePointerInfo &PtrInfo,
557 LocationSize Size) {
558 assert((!Size.hasValue() ||
559 Size.getValue().getKnownMinValue() != ~UINT64_C(0)) &&
560 "Unexpected an unknown size to be represented using "
561 "LocationSize::beforeOrAfter()");
562 return new (Allocator)
563 MachineMemOperand(PtrInfo, MMO->getFlags(), Size, MMO->getBaseAlign(),
564 AAMDNodes(), nullptr, MMO->getSyncScopeID(),
565 MMO->getSuccessOrdering(), MMO->getFailureOrdering());
566}
567
568MachineMemOperand *MachineFunction::getMachineMemOperand(
569 const MachineMemOperand *MMO, const MachinePointerInfo &PtrInfo, LLT Ty) {
570 return new (Allocator)
571 MachineMemOperand(PtrInfo, MMO->getFlags(), Ty, MMO->getBaseAlign(),
572 AAMDNodes(), nullptr, MMO->getSyncScopeID(),
573 MMO->getSuccessOrdering(), MMO->getFailureOrdering());
574}
575
576MachineMemOperand *
577MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
578 int64_t Offset, LLT Ty) {
579 const MachinePointerInfo &PtrInfo = MMO->getPointerInfo();
580
581 // If there is no pointer value, the offset isn't tracked so we need to adjust
582 // the base alignment.
583 Align Alignment = PtrInfo.V.isNull()
584 ? commonAlignment(A: MMO->getBaseAlign(), Offset)
585 : MMO->getBaseAlign();
586
587 // Do not preserve ranges, since we don't necessarily know what the high bits
588 // are anymore.
589 return new (Allocator) MachineMemOperand(
590 PtrInfo.getWithOffset(O: Offset), MMO->getFlags(), Ty, Alignment,
591 MMO->getAAInfo(), nullptr, MMO->getSyncScopeID(),
592 MMO->getSuccessOrdering(), MMO->getFailureOrdering());
593}
594
595MachineMemOperand *
596MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
597 const AAMDNodes &AAInfo) {
598 MachinePointerInfo MPI = MMO->getValue() ?
599 MachinePointerInfo(MMO->getValue(), MMO->getOffset()) :
600 MachinePointerInfo(MMO->getPseudoValue(), MMO->getOffset());
601
602 return new (Allocator) MachineMemOperand(
603 MPI, MMO->getFlags(), MMO->getSize(), MMO->getBaseAlign(), AAInfo,
604 MMO->getRanges(), MMO->getSyncScopeID(), MMO->getSuccessOrdering(),
605 MMO->getFailureOrdering());
606}
607
608MachineMemOperand *
609MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
610 MachineMemOperand::Flags Flags) {
611 return new (Allocator) MachineMemOperand(
612 MMO->getPointerInfo(), Flags, MMO->getSize(), MMO->getBaseAlign(),
613 MMO->getAAInfo(), MMO->getRanges(), MMO->getSyncScopeID(),
614 MMO->getSuccessOrdering(), MMO->getFailureOrdering());
615}
616
617MachineInstr::ExtraInfo *MachineFunction::createMIExtraInfo(
618 ArrayRef<MachineMemOperand *> MMOs, MCSymbol *PreInstrSymbol,
619 MCSymbol *PostInstrSymbol, MDNode *HeapAllocMarker, MDNode *PCSections,
620 uint32_t CFIType, MDNode *MMRAs, Value *DS) {
621 return MachineInstr::ExtraInfo::create(Allocator, MMOs, PreInstrSymbol,
622 PostInstrSymbol, HeapAllocMarker,
623 PCSections, CFIType, MMRAs, DS);
624}
625
626const char *MachineFunction::createExternalSymbolName(StringRef Name) {
627 char *Dest = Allocator.Allocate<char>(Num: Name.size() + 1);
628 llvm::copy(Range&: Name, Out: Dest);
629 Dest[Name.size()] = 0;
630 return Dest;
631}
632
633uint32_t *MachineFunction::allocateRegMask() {
634 unsigned NumRegs = getSubtarget().getRegisterInfo()->getNumRegs();
635 unsigned Size = MachineOperand::getRegMaskSize(NumRegs);
636 uint32_t *Mask = Allocator.Allocate<uint32_t>(Num: Size);
637 memset(s: Mask, c: 0, n: Size * sizeof(Mask[0]));
638 return Mask;
639}
640
641ArrayRef<int> MachineFunction::allocateShuffleMask(ArrayRef<int> Mask) {
642 int* AllocMask = Allocator.Allocate<int>(Num: Mask.size());
643 copy(Range&: Mask, Out: AllocMask);
644 return {AllocMask, Mask.size()};
645}
646
647#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
648LLVM_DUMP_METHOD void MachineFunction::dump() const {
649 print(dbgs());
650}
651#endif
652
653StringRef MachineFunction::getName() const {
654 return getFunction().getName();
655}
656
657void MachineFunction::print(raw_ostream &OS, const SlotIndexes *Indexes) const {
658 OS << "# Machine code for function " << getName() << ": ";
659 getProperties().print(OS);
660 OS << '\n';
661
662 // Print Frame Information
663 FrameInfo->print(MF: *this, OS);
664
665 // Print JumpTable Information
666 if (JumpTableInfo)
667 JumpTableInfo->print(OS);
668
669 // Print Constant Pool
670 ConstantPool->print(OS);
671
672 const TargetRegisterInfo *TRI = getSubtarget().getRegisterInfo();
673
674 if (RegInfo && !RegInfo->livein_empty()) {
675 OS << "Function Live Ins: ";
676 for (MachineRegisterInfo::livein_iterator
677 I = RegInfo->livein_begin(), E = RegInfo->livein_end(); I != E; ++I) {
678 OS << printReg(Reg: I->first, TRI);
679 if (I->second)
680 OS << " in " << printReg(Reg: I->second, TRI);
681 if (std::next(x: I) != E)
682 OS << ", ";
683 }
684 OS << '\n';
685 }
686
687 ModuleSlotTracker MST(getFunction().getParent());
688 MST.incorporateFunction(F: getFunction());
689 for (const auto &BB : *this) {
690 OS << '\n';
691 // If we print the whole function, print it at its most verbose level.
692 BB.print(OS, MST, Indexes, /*IsStandalone=*/true);
693 }
694
695 OS << "\n# End machine code for function " << getName() << ".\n\n";
696}
697
698/// True if this function needs frame moves for debug or exceptions.
699bool MachineFunction::needsFrameMoves() const {
700 // TODO: Ideally, what we'd like is to have a switch that allows emitting
701 // synchronous (precise at call-sites only) CFA into .eh_frame. However, even
702 // under this switch, we'd like .debug_frame to be precise when using -g. At
703 // this moment, there's no way to specify that some CFI directives go into
704 // .eh_frame only, while others go into .debug_frame only.
705 return getTarget().Options.ForceDwarfFrameSection ||
706 F.needsUnwindTableEntry() ||
707 !F.getParent()->debug_compile_units().empty();
708}
709
710MachineFunction::CallSiteInfo::CallSiteInfo(const CallBase &CB) {
711 if (MDNode *Node = CB.getMetadata(KindID: llvm::LLVMContext::MD_call_target))
712 CallTarget = Node;
713
714 // Numeric callee_type ids are only for indirect calls.
715 if (!CB.isIndirectCall())
716 return;
717
718 MDNode *CalleeTypeList = CB.getMetadata(KindID: LLVMContext::MD_callee_type);
719 if (!CalleeTypeList)
720 return;
721
722 for (const MDOperand &Op : CalleeTypeList->operands()) {
723 MDNode *TypeMD = cast<MDNode>(Val: Op);
724 MDString *TypeIdStr = cast<MDString>(Val: TypeMD->getOperand(I: 1));
725 // Compute numeric type id from generalized type id string
726 uint64_t TypeIdVal = MD5Hash(Str: TypeIdStr->getString());
727 IntegerType *Int64Ty = Type::getInt64Ty(C&: CB.getContext());
728 CalleeTypeIds.push_back(
729 Elt: ConstantInt::get(Ty: Int64Ty, V: TypeIdVal, /*IsSigned=*/false));
730 }
731}
732
733template <>
734struct llvm::DOTGraphTraits<const MachineFunction *>
735 : public DefaultDOTGraphTraits {
736 DOTGraphTraits(bool isSimple = false) : DefaultDOTGraphTraits(isSimple) {}
737
738 static std::string getGraphName(const MachineFunction *F) {
739 return ("CFG for '" + F->getName() + "' function").str();
740 }
741
742 std::string getNodeLabel(const MachineBasicBlock *Node,
743 const MachineFunction *Graph) {
744 std::string OutStr;
745 {
746 raw_string_ostream OSS(OutStr);
747
748 if (isSimple()) {
749 OSS << printMBBReference(MBB: *Node);
750 if (const BasicBlock *BB = Node->getBasicBlock())
751 OSS << ": " << BB->getName();
752 } else
753 Node->print(OS&: OSS);
754 }
755
756 if (OutStr[0] == '\n')
757 OutStr.erase(position: OutStr.begin());
758
759 // Process string output to make it nicer...
760 for (unsigned i = 0; i != OutStr.length(); ++i)
761 if (OutStr[i] == '\n') { // Left justify
762 OutStr[i] = '\\';
763 OutStr.insert(p: OutStr.begin() + i + 1, c: 'l');
764 }
765 return OutStr;
766 }
767};
768
769void MachineFunction::viewCFG() const
770{
771#ifndef NDEBUG
772 ViewGraph(this, "mf" + getName());
773#else
774 errs() << "MachineFunction::viewCFG is only available in debug builds on "
775 << "systems with Graphviz or gv!\n";
776#endif // NDEBUG
777}
778
779void MachineFunction::viewCFGOnly() const
780{
781#ifndef NDEBUG
782 ViewGraph(this, "mf" + getName(), true);
783#else
784 errs() << "MachineFunction::viewCFGOnly is only available in debug builds on "
785 << "systems with Graphviz or gv!\n";
786#endif // NDEBUG
787}
788
789/// Add the specified physical register as a live-in value and
790/// create a corresponding virtual register for it.
791Register MachineFunction::addLiveIn(MCRegister PReg,
792 const TargetRegisterClass *RC) {
793 MachineRegisterInfo &MRI = getRegInfo();
794 Register VReg = MRI.getLiveInVirtReg(PReg);
795 if (VReg) {
796 const TargetRegisterClass *VRegRC = MRI.getRegClass(Reg: VReg);
797 (void)VRegRC;
798 // A physical register can be added several times.
799 // Between two calls, the register class of the related virtual register
800 // may have been constrained to match some operation constraints.
801 // In that case, check that the current register class includes the
802 // physical register and is a sub class of the specified RC.
803 assert((VRegRC == RC || (VRegRC->contains(PReg) &&
804 RC->hasSubClassEq(VRegRC))) &&
805 "Register class mismatch!");
806 return VReg;
807 }
808 VReg = MRI.createVirtualRegister(RegClass: RC);
809 MRI.addLiveIn(Reg: PReg, vreg: VReg);
810 return VReg;
811}
812
813/// Return the MCSymbol for the specified non-empty jump table.
814/// If isLinkerPrivate is specified, an 'l' label is returned, otherwise a
815/// normal 'L' label is returned.
816MCSymbol *MachineFunction::getJTISymbol(unsigned JTI, MCContext &Ctx,
817 bool isLinkerPrivate) const {
818 const DataLayout &DL = getDataLayout();
819 assert(JumpTableInfo && "No jump tables");
820 assert(JTI < JumpTableInfo->getJumpTables().size() && "Invalid JTI!");
821
822 StringRef Prefix = isLinkerPrivate ? DL.getLinkerPrivateGlobalPrefix()
823 : DL.getInternalSymbolPrefix();
824 SmallString<60> Name;
825 raw_svector_ostream(Name)
826 << Prefix << "JTI" << getFunctionNumber() << '_' << JTI;
827 return Ctx.getOrCreateSymbol(Name);
828}
829
830/// Return a function-local symbol to represent the PIC base.
831MCSymbol *MachineFunction::getPICBaseSymbol() const {
832 const DataLayout &DL = getDataLayout();
833 return Ctx.getOrCreateSymbol(Name: Twine(DL.getInternalSymbolPrefix()) +
834 Twine(getFunctionNumber()) + "$pb");
835}
836
837/// \name Exception Handling
838/// \{
839
840LandingPadInfo &
841MachineFunction::getOrCreateLandingPadInfo(MachineBasicBlock *LandingPad) {
842 unsigned N = LandingPads.size();
843 for (unsigned i = 0; i < N; ++i) {
844 LandingPadInfo &LP = LandingPads[i];
845 if (LP.LandingPadBlock == LandingPad)
846 return LP;
847 }
848
849 LandingPads.push_back(x: LandingPadInfo(LandingPad));
850 return LandingPads[N];
851}
852
853void MachineFunction::addInvoke(MachineBasicBlock *LandingPad,
854 MCSymbol *BeginLabel, MCSymbol *EndLabel) {
855 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
856 LP.BeginLabels.push_back(Elt: BeginLabel);
857 LP.EndLabels.push_back(Elt: EndLabel);
858}
859
860MCSymbol *MachineFunction::addLandingPad(MachineBasicBlock *LandingPad) {
861 MCSymbol *LandingPadLabel = Ctx.createTempSymbol();
862 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
863 LP.LandingPadLabel = LandingPadLabel;
864
865 BasicBlock::const_iterator FirstI =
866 LandingPad->getBasicBlock()->getFirstNonPHIIt();
867 if (const auto *LPI = dyn_cast<LandingPadInst>(Val&: FirstI)) {
868 // If there's no typeid list specified, then "cleanup" is implicit.
869 // Otherwise, id 0 is reserved for the cleanup action.
870 if (LPI->isCleanup() && LPI->getNumClauses() != 0)
871 LP.TypeIds.push_back(x: 0);
872
873 // FIXME: New EH - Add the clauses in reverse order. This isn't 100%
874 // correct, but we need to do it this way because of how the DWARF EH
875 // emitter processes the clauses.
876 for (unsigned I = LPI->getNumClauses(); I != 0; --I) {
877 Value *Val = LPI->getClause(Idx: I - 1);
878 if (LPI->isCatch(Idx: I - 1)) {
879 LP.TypeIds.push_back(
880 x: getTypeIDFor(TI: dyn_cast<GlobalValue>(Val: Val->stripPointerCasts())));
881 } else {
882 // Add filters in a list.
883 auto *CVal = cast<Constant>(Val);
884 SmallVector<unsigned, 4> FilterList;
885 for (const Use &U : CVal->operands())
886 FilterList.push_back(
887 Elt: getTypeIDFor(TI: cast<GlobalValue>(Val: U->stripPointerCasts())));
888
889 LP.TypeIds.push_back(x: getFilterIDFor(TyIds: FilterList));
890 }
891 }
892
893 } else if (const auto *CPI = dyn_cast<CatchPadInst>(Val&: FirstI)) {
894 for (unsigned I = CPI->arg_size(); I != 0; --I) {
895 auto *TypeInfo =
896 dyn_cast<GlobalValue>(Val: CPI->getArgOperand(i: I - 1)->stripPointerCasts());
897 LP.TypeIds.push_back(x: getTypeIDFor(TI: TypeInfo));
898 }
899
900 } else {
901 assert(isa<CleanupPadInst>(FirstI) && "Invalid landingpad!");
902 }
903
904 return LandingPadLabel;
905}
906
907void MachineFunction::setCallSiteLandingPad(MCSymbol *Sym,
908 ArrayRef<unsigned> Sites) {
909 LPadToCallSiteMap[Sym].append(in_start: Sites.begin(), in_end: Sites.end());
910}
911
912unsigned MachineFunction::getTypeIDFor(const GlobalValue *TI) {
913 for (unsigned i = 0, N = TypeInfos.size(); i != N; ++i)
914 if (TypeInfos[i] == TI) return i + 1;
915
916 TypeInfos.push_back(x: TI);
917 return TypeInfos.size();
918}
919
920int MachineFunction::getFilterIDFor(ArrayRef<unsigned> TyIds) {
921 // If the new filter coincides with the tail of an existing filter, then
922 // re-use the existing filter. Folding filters more than this requires
923 // re-ordering filters and/or their elements - probably not worth it.
924 for (unsigned i : FilterEnds) {
925 unsigned j = TyIds.size();
926
927 while (i && j)
928 if (FilterIds[--i] != TyIds[--j])
929 goto try_next;
930
931 if (!j)
932 // The new filter coincides with range [i, end) of the existing filter.
933 return -(1 + i);
934
935try_next:;
936 }
937
938 // Add the new filter.
939 int FilterID = -(1 + FilterIds.size());
940 FilterIds.reserve(n: FilterIds.size() + TyIds.size() + 1);
941 llvm::append_range(C&: FilterIds, R&: TyIds);
942 FilterEnds.push_back(x: FilterIds.size());
943 FilterIds.push_back(x: 0); // terminator
944 return FilterID;
945}
946
947MachineFunction::CallSiteInfoMap::iterator
948MachineFunction::getCallSiteInfo(const MachineInstr *MI) {
949 assert(MI->isCandidateForAdditionalCallInfo() &&
950 "Call site info refers only to call (MI) candidates");
951
952 if (!Target.Options.EmitCallSiteInfo && !Target.Options.EmitCallGraphSection)
953 return CallSitesInfo.end();
954 return CallSitesInfo.find(Val: MI);
955}
956
957/// Return the call machine instruction or find a call within bundle.
958static const MachineInstr *getCallInstr(const MachineInstr *MI) {
959 if (!MI->isBundle())
960 return MI;
961
962 for (const auto &BMI : make_range(x: getBundleStart(I: MI->getIterator()),
963 y: getBundleEnd(I: MI->getIterator())))
964 if (BMI.isCandidateForAdditionalCallInfo())
965 return &BMI;
966
967 llvm_unreachable("Unexpected bundle without a call site candidate");
968}
969
970void MachineFunction::eraseAdditionalCallInfo(const MachineInstr *MI) {
971 assert(MI->shouldUpdateAdditionalCallInfo() &&
972 "Call info refers only to call (MI) candidates or "
973 "candidates inside bundles");
974
975 const MachineInstr *CallMI = getCallInstr(MI);
976
977 CallSiteInfoMap::iterator CSIt = getCallSiteInfo(MI: CallMI);
978 if (CSIt != CallSitesInfo.end())
979 CallSitesInfo.erase(I: CSIt);
980
981 CalledGlobalsInfo.erase(Val: CallMI);
982}
983
984void MachineFunction::copyAdditionalCallInfo(const MachineInstr *Old,
985 const MachineInstr *New) {
986 assert(Old->shouldUpdateAdditionalCallInfo() &&
987 "Call info refers only to call (MI) candidates or "
988 "candidates inside bundles");
989
990 if (!New->isCandidateForAdditionalCallInfo())
991 return eraseAdditionalCallInfo(MI: Old);
992
993 const MachineInstr *OldCallMI = getCallInstr(MI: Old);
994 CallSiteInfoMap::iterator CSIt = getCallSiteInfo(MI: OldCallMI);
995 if (CSIt != CallSitesInfo.end()) {
996 CallSiteInfo CSInfo = CSIt->second;
997 CallSitesInfo[New] = std::move(CSInfo);
998 }
999
1000 CalledGlobalsMap::iterator CGIt = CalledGlobalsInfo.find(Val: OldCallMI);
1001 if (CGIt != CalledGlobalsInfo.end()) {
1002 CalledGlobalInfo CGInfo = CGIt->second;
1003 CalledGlobalsInfo[New] = std::move(CGInfo);
1004 }
1005}
1006
1007void MachineFunction::moveAdditionalCallInfo(const MachineInstr *Old,
1008 const MachineInstr *New) {
1009 assert(Old->shouldUpdateAdditionalCallInfo() &&
1010 "Call info refers only to call (MI) candidates or "
1011 "candidates inside bundles");
1012
1013 if (!New->isCandidateForAdditionalCallInfo())
1014 return eraseAdditionalCallInfo(MI: Old);
1015
1016 const MachineInstr *OldCallMI = getCallInstr(MI: Old);
1017 CallSiteInfoMap::iterator CSIt = getCallSiteInfo(MI: OldCallMI);
1018 if (CSIt != CallSitesInfo.end()) {
1019 CallSiteInfo CSInfo = std::move(CSIt->second);
1020 CallSitesInfo.erase(I: CSIt);
1021 CallSitesInfo[New] = std::move(CSInfo);
1022 }
1023
1024 CalledGlobalsMap::iterator CGIt = CalledGlobalsInfo.find(Val: OldCallMI);
1025 if (CGIt != CalledGlobalsInfo.end()) {
1026 CalledGlobalInfo CGInfo = std::move(CGIt->second);
1027 CalledGlobalsInfo.erase(I: CGIt);
1028 CalledGlobalsInfo[New] = std::move(CGInfo);
1029 }
1030}
1031
1032void MachineFunction::setDebugInstrNumberingCount(unsigned Num) {
1033 DebugInstrNumberingCount = Num;
1034}
1035
1036void MachineFunction::makeDebugValueSubstitution(DebugInstrOperandPair A,
1037 DebugInstrOperandPair B,
1038 unsigned Subreg) {
1039 // Catch any accidental self-loops.
1040 assert(A.first != B.first);
1041 // Don't allow any substitutions _from_ the memory operand number.
1042 assert(A.second != DebugOperandMemNumber);
1043
1044 DebugValueSubstitutions.push_back(Elt: {A, B, Subreg});
1045}
1046
1047void MachineFunction::substituteDebugValuesForInst(const MachineInstr &Old,
1048 MachineInstr &New,
1049 unsigned MaxOperand) {
1050 // If the Old instruction wasn't tracked at all, there is no work to do.
1051 unsigned OldInstrNum = Old.peekDebugInstrNum();
1052 if (!OldInstrNum)
1053 return;
1054
1055 // Iterate over all operands looking for defs to create substitutions for.
1056 // Avoid creating new instr numbers unless we create a new substitution.
1057 // While this has no functional effect, it risks confusing someone reading
1058 // MIR output.
1059 // Examine all the operands, or the first N specified by the caller.
1060 MaxOperand = std::min(a: MaxOperand, b: Old.getNumOperands());
1061 for (unsigned int I = 0; I < MaxOperand; ++I) {
1062 const auto &OldMO = Old.getOperand(i: I);
1063 auto &NewMO = New.getOperand(i: I);
1064 (void)NewMO;
1065
1066 if (!OldMO.isReg() || !OldMO.isDef())
1067 continue;
1068 assert(NewMO.isDef());
1069
1070 unsigned NewInstrNum = New.getDebugInstrNum();
1071 makeDebugValueSubstitution(A: std::make_pair(x&: OldInstrNum, y&: I),
1072 B: std::make_pair(x&: NewInstrNum, y&: I));
1073 }
1074}
1075
1076auto MachineFunction::salvageCopySSA(
1077 MachineInstr &MI, DenseMap<Register, DebugInstrOperandPair> &DbgPHICache)
1078 -> DebugInstrOperandPair {
1079 const TargetInstrInfo &TII = *getSubtarget().getInstrInfo();
1080
1081 // Check whether this copy-like instruction has already been salvaged into
1082 // an operand pair.
1083 Register Dest;
1084 if (auto CopyDstSrc = TII.isCopyLikeInstr(MI)) {
1085 Dest = CopyDstSrc->Destination->getReg();
1086 } else {
1087 assert(MI.isSubregToReg());
1088 Dest = MI.getOperand(i: 0).getReg();
1089 }
1090
1091 auto CacheIt = DbgPHICache.find(Val: Dest);
1092 if (CacheIt != DbgPHICache.end())
1093 return CacheIt->second;
1094
1095 // Calculate the instruction number to use, or install a DBG_PHI.
1096 auto OperandPair = salvageCopySSAImpl(MI);
1097 DbgPHICache.insert(KV: {Dest, OperandPair});
1098 return OperandPair;
1099}
1100
1101auto MachineFunction::salvageCopySSAImpl(MachineInstr &MI)
1102 -> DebugInstrOperandPair {
1103 MachineRegisterInfo &MRI = getRegInfo();
1104 const TargetRegisterInfo &TRI = *MRI.getTargetRegisterInfo();
1105 const TargetInstrInfo &TII = *getSubtarget().getInstrInfo();
1106
1107 // Chase the value read by a copy-like instruction back to the instruction
1108 // that ultimately _defines_ that value. This may pass:
1109 // * Through multiple intermediate copies, including subregister moves /
1110 // copies,
1111 // * Copies from physical registers that must then be traced back to the
1112 // defining instruction,
1113 // * Or, physical registers may be live-in to (only) the entry block, which
1114 // requires a DBG_PHI to be created.
1115 // We can pursue this problem in that order: trace back through copies,
1116 // optionally through a physical register, to a defining instruction. We
1117 // should never move from physreg to vreg. As we're still in SSA form, no need
1118 // to worry about partial definitions of registers.
1119
1120 // Helper lambda to interpret a copy-like instruction. Takes instruction,
1121 // returns the register read and any subregister identifying which part is
1122 // read.
1123 auto GetRegAndSubreg =
1124 [&](const MachineInstr &Cpy) -> std::pair<Register, unsigned> {
1125 Register NewReg, OldReg;
1126 unsigned SubReg;
1127 if (Cpy.isCopy()) {
1128 OldReg = Cpy.getOperand(i: 0).getReg();
1129 NewReg = Cpy.getOperand(i: 1).getReg();
1130 SubReg = Cpy.getOperand(i: 1).getSubReg();
1131 } else if (Cpy.isSubregToReg()) {
1132 OldReg = Cpy.getOperand(i: 0).getReg();
1133 NewReg = Cpy.getOperand(i: 1).getReg();
1134 SubReg = Cpy.getOperand(i: 2).getImm();
1135 } else {
1136 auto CopyDetails = *TII.isCopyInstr(MI: Cpy);
1137 const MachineOperand &Src = *CopyDetails.Source;
1138 const MachineOperand &Dest = *CopyDetails.Destination;
1139 OldReg = Dest.getReg();
1140 NewReg = Src.getReg();
1141 SubReg = Src.getSubReg();
1142 }
1143
1144 return {NewReg, SubReg};
1145 };
1146
1147 // First seek either the defining instruction, or a copy from a physreg.
1148 // During search, the current state is the current copy instruction, and which
1149 // register we've read. Accumulate qualifying subregisters into SubregsSeen;
1150 // deal with those later.
1151 auto State = GetRegAndSubreg(MI);
1152 auto CurInst = MI.getIterator();
1153 SmallVector<unsigned, 4> SubregsSeen;
1154 while (true) {
1155 // If we've found a copy from a physreg, first portion of search is over.
1156 if (!State.first.isVirtual())
1157 break;
1158
1159 // Record any subregister qualifier.
1160 if (State.second)
1161 SubregsSeen.push_back(Elt: State.second);
1162
1163 assert(MRI.hasOneDef(State.first));
1164 MachineInstr &Inst = *MRI.def_begin(RegNo: State.first)->getParent();
1165 CurInst = Inst.getIterator();
1166
1167 // Any non-copy instruction is the defining instruction we're seeking.
1168 if (!Inst.isCopyLike() && !TII.isCopyLikeInstr(MI: Inst))
1169 break;
1170 State = GetRegAndSubreg(Inst);
1171 };
1172
1173 // Helper lambda to apply additional subregister substitutions to a known
1174 // instruction/operand pair. Adds new (fake) substitutions so that we can
1175 // record the subregister. FIXME: this isn't very space efficient if multiple
1176 // values are tracked back through the same copies; cache something later.
1177 auto ApplySubregisters =
1178 [&](DebugInstrOperandPair P) -> DebugInstrOperandPair {
1179 for (unsigned Subreg : reverse(C&: SubregsSeen)) {
1180 // Fetch a new instruction number, not attached to an actual instruction.
1181 unsigned NewInstrNumber = getNewDebugInstrNum();
1182 // Add a substitution from the "new" number to the known one, with a
1183 // qualifying subreg.
1184 makeDebugValueSubstitution(A: {NewInstrNumber, 0}, B: P, Subreg);
1185 // Return the new number; to find the underlying value, consumers need to
1186 // deal with the qualifying subreg.
1187 P = {NewInstrNumber, 0};
1188 }
1189 return P;
1190 };
1191
1192 // If we managed to find the defining instruction after COPYs, return an
1193 // instruction / operand pair after adding subregister qualifiers.
1194 if (State.first.isVirtual()) {
1195 // Virtual register def -- we can just look up where this happens.
1196 MachineInstr *Inst = MRI.def_begin(RegNo: State.first)->getParent();
1197 for (auto &MO : Inst->all_defs()) {
1198 if (MO.getReg() != State.first)
1199 continue;
1200 return ApplySubregisters({Inst->getDebugInstrNum(), MO.getOperandNo()});
1201 }
1202
1203 llvm_unreachable("Vreg def with no corresponding operand?");
1204 }
1205
1206 // Our search ended in a copy from a physreg: walk back up the function
1207 // looking for whatever defines the physreg.
1208 assert(CurInst->isCopyLike() || TII.isCopyInstr(*CurInst));
1209 State = GetRegAndSubreg(*CurInst);
1210 Register RegToSeek = State.first;
1211
1212 auto RMII = CurInst->getReverseIterator();
1213 auto PrevInstrs = make_range(x: RMII, y: CurInst->getParent()->instr_rend());
1214 for (auto &ToExamine : PrevInstrs) {
1215 for (auto &MO : ToExamine.all_defs()) {
1216 // Test for operand that defines something aliasing RegToSeek.
1217 if (!TRI.regsOverlap(RegA: RegToSeek, RegB: MO.getReg()))
1218 continue;
1219
1220 return ApplySubregisters(
1221 {ToExamine.getDebugInstrNum(), MO.getOperandNo()});
1222 }
1223 }
1224
1225 MachineBasicBlock &InsertBB = *CurInst->getParent();
1226
1227 // We reached the start of the block before finding a defining instruction.
1228 // There are numerous scenarios where this can happen:
1229 // * Constant physical registers,
1230 // * Several intrinsics that allow LLVM-IR to read arbitary registers,
1231 // * Arguments in the entry block,
1232 // * Exception handling landing pads.
1233 // Validating all of them is too difficult, so just insert a DBG_PHI reading
1234 // the variable value at this position, rather than checking it makes sense.
1235
1236 // Create DBG_PHI for specified physreg.
1237 auto Builder = BuildMI(BB&: InsertBB, I: InsertBB.getFirstNonPHI(), MIMD: DebugLoc(),
1238 MCID: TII.get(Opcode: TargetOpcode::DBG_PHI));
1239 Builder.addReg(RegNo: State.first);
1240 unsigned NewNum = getNewDebugInstrNum();
1241 Builder.addImm(Val: NewNum);
1242 return ApplySubregisters({NewNum, 0u});
1243}
1244
1245void MachineFunction::finalizeDebugInstrRefs() {
1246 auto *TII = getSubtarget().getInstrInfo();
1247
1248 auto MakeUndefDbgValue = [&](MachineInstr &MI) {
1249 const MCInstrDesc &RefII = TII->get(Opcode: TargetOpcode::DBG_VALUE_LIST);
1250 MI.setDesc(RefII);
1251 MI.setDebugValueUndef();
1252 };
1253
1254 DenseMap<Register, DebugInstrOperandPair> ArgDbgPHIs;
1255 for (auto &MBB : *this) {
1256 for (auto &MI : MBB) {
1257 if (!MI.isDebugRef())
1258 continue;
1259
1260 bool IsValidRef = true;
1261
1262 for (MachineOperand &MO : MI.debug_operands()) {
1263 if (!MO.isReg())
1264 continue;
1265
1266 Register Reg = MO.getReg();
1267
1268 // Some vregs can be deleted as redundant in the meantime. Mark those
1269 // as DBG_VALUE $noreg. Additionally, some normal instructions are
1270 // quickly deleted, leaving dangling references to vregs with no def.
1271 if (Reg == 0 || !RegInfo->hasOneDef(RegNo: Reg)) {
1272 IsValidRef = false;
1273 break;
1274 }
1275
1276 assert(Reg.isVirtual());
1277 MachineInstr &DefMI = *RegInfo->def_instr_begin(RegNo: Reg);
1278
1279 // If we've found a copy-like instruction, follow it back to the
1280 // instruction that defines the source value, see salvageCopySSA docs
1281 // for why this is important.
1282 if (DefMI.isCopyLike() || TII->isCopyInstr(MI: DefMI)) {
1283 auto Result = salvageCopySSA(MI&: DefMI, DbgPHICache&: ArgDbgPHIs);
1284 MO.ChangeToDbgInstrRef(InstrIdx: Result.first, OpIdx: Result.second);
1285 } else {
1286 // Otherwise, identify the operand number that the VReg refers to.
1287 unsigned OperandIdx = 0;
1288 for (const auto &DefMO : DefMI.operands()) {
1289 if (DefMO.isReg() && DefMO.isDef() && DefMO.getReg() == Reg)
1290 break;
1291 ++OperandIdx;
1292 }
1293 assert(OperandIdx < DefMI.getNumOperands());
1294
1295 // Morph this instr ref to point at the given instruction and operand.
1296 unsigned ID = DefMI.getDebugInstrNum();
1297 MO.ChangeToDbgInstrRef(InstrIdx: ID, OpIdx: OperandIdx);
1298 }
1299 }
1300
1301 if (!IsValidRef)
1302 MakeUndefDbgValue(MI);
1303 }
1304 }
1305}
1306
1307bool MachineFunction::shouldUseDebugInstrRef() const {
1308 // Disable instr-ref at -O0: it's very slow (in compile time). We can still
1309 // have optimized code inlined into this unoptimized code, however with
1310 // fewer and less aggressive optimizations happening, coverage and accuracy
1311 // should not suffer.
1312 if (getTarget().getOptLevel() == CodeGenOptLevel::None)
1313 return false;
1314
1315 // Don't use instr-ref if this function is marked optnone.
1316 if (F.hasFnAttribute(Kind: Attribute::OptimizeNone))
1317 return false;
1318
1319 if (llvm::debuginfoShouldUseDebugInstrRef(T: getTarget().getTargetTriple()))
1320 return true;
1321
1322 return false;
1323}
1324
1325bool MachineFunction::useDebugInstrRef() const {
1326 return UseDebugInstrRef;
1327}
1328
1329void MachineFunction::setUseDebugInstrRef(bool Use) {
1330 UseDebugInstrRef = Use;
1331}
1332
1333// Use one million as a high / reserved number.
1334const unsigned MachineFunction::DebugOperandMemNumber = 1000000;
1335
1336/// \}
1337
1338//===----------------------------------------------------------------------===//
1339// MachineJumpTableInfo implementation
1340//===----------------------------------------------------------------------===//
1341
1342MachineJumpTableEntry::MachineJumpTableEntry(
1343 const std::vector<MachineBasicBlock *> &MBBs)
1344 : MBBs(MBBs), Hotness(MachineFunctionDataHotness::Unknown) {}
1345
1346/// Return the size of each entry in the jump table.
1347unsigned MachineJumpTableInfo::getEntrySize(const DataLayout &TD) const {
1348 // The size of a jump table entry is 4 bytes unless the entry is just the
1349 // address of a block, in which case it is the pointer size.
1350 switch (getEntryKind()) {
1351 case MachineJumpTableInfo::EK_BlockAddress:
1352 return TD.getPointerSize();
1353 case MachineJumpTableInfo::EK_GPRel64BlockAddress:
1354 case MachineJumpTableInfo::EK_LabelDifference64:
1355 return 8;
1356 case MachineJumpTableInfo::EK_GPRel32BlockAddress:
1357 case MachineJumpTableInfo::EK_LabelDifference32:
1358 case MachineJumpTableInfo::EK_Custom32:
1359 return 4;
1360 case MachineJumpTableInfo::EK_Inline:
1361 return 0;
1362 }
1363 llvm_unreachable("Unknown jump table encoding!");
1364}
1365
1366/// Return the alignment of each entry in the jump table.
1367unsigned MachineJumpTableInfo::getEntryAlignment(const DataLayout &TD) const {
1368 // The alignment of a jump table entry is the alignment of int32 unless the
1369 // entry is just the address of a block, in which case it is the pointer
1370 // alignment.
1371 switch (getEntryKind()) {
1372 case MachineJumpTableInfo::EK_BlockAddress:
1373 return TD.getPointerABIAlignment(AS: 0).value();
1374 case MachineJumpTableInfo::EK_GPRel64BlockAddress:
1375 case MachineJumpTableInfo::EK_LabelDifference64:
1376 return TD.getABIIntegerTypeAlignment(BitWidth: 64).value();
1377 case MachineJumpTableInfo::EK_GPRel32BlockAddress:
1378 case MachineJumpTableInfo::EK_LabelDifference32:
1379 case MachineJumpTableInfo::EK_Custom32:
1380 return TD.getABIIntegerTypeAlignment(BitWidth: 32).value();
1381 case MachineJumpTableInfo::EK_Inline:
1382 return 1;
1383 }
1384 llvm_unreachable("Unknown jump table encoding!");
1385}
1386
1387/// Create a new jump table entry in the jump table info.
1388unsigned MachineJumpTableInfo::createJumpTableIndex(
1389 const std::vector<MachineBasicBlock*> &DestBBs) {
1390 assert(!DestBBs.empty() && "Cannot create an empty jump table!");
1391 JumpTables.push_back(x: MachineJumpTableEntry(DestBBs));
1392 return JumpTables.size()-1;
1393}
1394
1395bool MachineJumpTableInfo::updateJumpTableEntryHotness(
1396 size_t JTI, MachineFunctionDataHotness Hotness) {
1397 assert(JTI < JumpTables.size() && "Invalid JTI!");
1398 // Record the largest hotness value.
1399 if (Hotness <= JumpTables[JTI].Hotness)
1400 return false;
1401
1402 JumpTables[JTI].Hotness = Hotness;
1403 return true;
1404}
1405
1406/// If Old is the target of any jump tables, update the jump tables to branch
1407/// to New instead.
1408bool MachineJumpTableInfo::ReplaceMBBInJumpTables(MachineBasicBlock *Old,
1409 MachineBasicBlock *New) {
1410 assert(Old != New && "Not making a change?");
1411 bool MadeChange = false;
1412 for (size_t i = 0, e = JumpTables.size(); i != e; ++i)
1413 ReplaceMBBInJumpTable(Idx: i, Old, New);
1414 return MadeChange;
1415}
1416
1417/// If MBB is present in any jump tables, remove it.
1418bool MachineJumpTableInfo::RemoveMBBFromJumpTables(MachineBasicBlock *MBB) {
1419 bool MadeChange = false;
1420 for (MachineJumpTableEntry &JTE : JumpTables) {
1421 auto removeBeginItr = std::remove(first: JTE.MBBs.begin(), last: JTE.MBBs.end(), value: MBB);
1422 MadeChange |= (removeBeginItr != JTE.MBBs.end());
1423 JTE.MBBs.erase(first: removeBeginItr, last: JTE.MBBs.end());
1424 }
1425 return MadeChange;
1426}
1427
1428/// If Old is a target of the jump tables, update the jump table to branch to
1429/// New instead.
1430bool MachineJumpTableInfo::ReplaceMBBInJumpTable(unsigned Idx,
1431 MachineBasicBlock *Old,
1432 MachineBasicBlock *New) {
1433 assert(Old != New && "Not making a change?");
1434 bool MadeChange = false;
1435 MachineJumpTableEntry &JTE = JumpTables[Idx];
1436 for (MachineBasicBlock *&MBB : JTE.MBBs)
1437 if (MBB == Old) {
1438 MBB = New;
1439 MadeChange = true;
1440 }
1441 return MadeChange;
1442}
1443
1444void MachineJumpTableInfo::print(raw_ostream &OS) const {
1445 if (JumpTables.empty()) return;
1446
1447 OS << "Jump Tables:\n";
1448
1449 for (unsigned i = 0, e = JumpTables.size(); i != e; ++i) {
1450 OS << printJumpTableEntryReference(Idx: i) << ':';
1451 for (const MachineBasicBlock *MBB : JumpTables[i].MBBs)
1452 OS << ' ' << printMBBReference(MBB: *MBB);
1453 OS << '\n';
1454 }
1455
1456 OS << '\n';
1457}
1458
1459#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
1460LLVM_DUMP_METHOD void MachineJumpTableInfo::dump() const { print(dbgs()); }
1461#endif
1462
1463Printable llvm::printJumpTableEntryReference(unsigned Idx) {
1464 return Printable([Idx](raw_ostream &OS) { OS << "%jump-table." << Idx; });
1465}
1466
1467//===----------------------------------------------------------------------===//
1468// MachineConstantPool implementation
1469//===----------------------------------------------------------------------===//
1470
1471void MachineConstantPoolValue::anchor() {}
1472
1473unsigned MachineConstantPoolValue::getSizeInBytes(const DataLayout &DL) const {
1474 return DL.getTypeAllocSize(Ty);
1475}
1476
1477unsigned MachineConstantPoolEntry::getSizeInBytes(const DataLayout &DL) const {
1478 if (isMachineConstantPoolEntry())
1479 return Val.MachineCPVal->getSizeInBytes(DL);
1480 return DL.getTypeAllocSize(Ty: Val.ConstVal->getType());
1481}
1482
1483bool MachineConstantPoolEntry::needsRelocation() const {
1484 if (isMachineConstantPoolEntry())
1485 return true;
1486 return Val.ConstVal->needsDynamicRelocation();
1487}
1488
1489SectionKind
1490MachineConstantPoolEntry::getSectionKind(const DataLayout *DL) const {
1491 if (needsRelocation())
1492 return SectionKind::getReadOnlyWithRel();
1493 switch (getSizeInBytes(DL: *DL)) {
1494 case 4:
1495 return SectionKind::getMergeableConst4();
1496 case 8:
1497 return SectionKind::getMergeableConst8();
1498 case 16:
1499 return SectionKind::getMergeableConst16();
1500 case 32:
1501 return SectionKind::getMergeableConst32();
1502 default:
1503 return SectionKind::getReadOnly();
1504 }
1505}
1506
1507MachineConstantPool::~MachineConstantPool() {
1508 // A constant may be a member of both Constants and MachineCPVsSharingEntries,
1509 // so keep track of which we've deleted to avoid double deletions.
1510 DenseSet<MachineConstantPoolValue*> Deleted;
1511 for (const MachineConstantPoolEntry &C : Constants)
1512 if (C.isMachineConstantPoolEntry()) {
1513 Deleted.insert(V: C.Val.MachineCPVal);
1514 delete C.Val.MachineCPVal;
1515 }
1516 for (MachineConstantPoolValue *CPV : MachineCPVsSharingEntries) {
1517 if (Deleted.count(V: CPV) == 0)
1518 delete CPV;
1519 }
1520}
1521
1522/// Test whether the given two constants can be allocated the same constant pool
1523/// entry referenced by \param A.
1524static bool CanShareConstantPoolEntry(const Constant *A, const Constant *B,
1525 const DataLayout &DL) {
1526 // Handle the trivial case quickly.
1527 if (A == B) return true;
1528
1529 // If they have the same type but weren't the same constant, quickly
1530 // reject them.
1531 if (A->getType() == B->getType()) return false;
1532
1533 // We can't handle structs or arrays.
1534 if (isa<StructType>(Val: A->getType()) || isa<ArrayType>(Val: A->getType()) ||
1535 isa<StructType>(Val: B->getType()) || isa<ArrayType>(Val: B->getType()))
1536 return false;
1537
1538 // For now, only support constants with the same size.
1539 uint64_t StoreSize = DL.getTypeStoreSize(Ty: A->getType());
1540 if (StoreSize != DL.getTypeStoreSize(Ty: B->getType()) || StoreSize > 128)
1541 return false;
1542
1543 bool ContainsUndefOrPoisonA = A->containsUndefOrPoisonElement();
1544
1545 Type *IntTy = IntegerType::get(C&: A->getContext(), NumBits: StoreSize*8);
1546
1547 // Try constant folding a bitcast of both instructions to an integer. If we
1548 // get two identical ConstantInt's, then we are good to share them. We use
1549 // the constant folding APIs to do this so that we get the benefit of
1550 // DataLayout.
1551 if (isa<PointerType>(Val: A->getType()))
1552 A = ConstantFoldCastOperand(Opcode: Instruction::PtrToInt,
1553 C: const_cast<Constant *>(A), DestTy: IntTy, DL);
1554 else if (A->getType() != IntTy)
1555 A = ConstantFoldCastOperand(Opcode: Instruction::BitCast, C: const_cast<Constant *>(A),
1556 DestTy: IntTy, DL);
1557 if (isa<PointerType>(Val: B->getType()))
1558 B = ConstantFoldCastOperand(Opcode: Instruction::PtrToInt,
1559 C: const_cast<Constant *>(B), DestTy: IntTy, DL);
1560 else if (B->getType() != IntTy)
1561 B = ConstantFoldCastOperand(Opcode: Instruction::BitCast, C: const_cast<Constant *>(B),
1562 DestTy: IntTy, DL);
1563
1564 if (A != B)
1565 return false;
1566
1567 // Constants only safely match if A doesn't contain undef/poison.
1568 // As we'll be reusing A, it doesn't matter if B contain undef/poison.
1569 // TODO: Handle cases where A and B have the same undef/poison elements.
1570 // TODO: Merge A and B with mismatching undef/poison elements.
1571 return !ContainsUndefOrPoisonA;
1572}
1573
1574/// Create a new entry in the constant pool or return an existing one.
1575/// User must specify the log2 of the minimum required alignment for the object.
1576unsigned MachineConstantPool::getConstantPoolIndex(const Constant *C,
1577 Align Alignment) {
1578 if (Alignment > PoolAlignment) PoolAlignment = Alignment;
1579
1580 // Check to see if we already have this constant.
1581 //
1582 // FIXME, this could be made much more efficient for large constant pools.
1583 for (unsigned i = 0, e = Constants.size(); i != e; ++i)
1584 if (!Constants[i].isMachineConstantPoolEntry() &&
1585 CanShareConstantPoolEntry(A: Constants[i].Val.ConstVal, B: C, DL)) {
1586 if (Constants[i].getAlign() < Alignment)
1587 Constants[i].Alignment = Alignment;
1588 return i;
1589 }
1590
1591 Constants.push_back(x: MachineConstantPoolEntry(C, Alignment));
1592 return Constants.size()-1;
1593}
1594
1595unsigned MachineConstantPool::getConstantPoolIndex(MachineConstantPoolValue *V,
1596 Align Alignment) {
1597 if (Alignment > PoolAlignment) PoolAlignment = Alignment;
1598
1599 // Check to see if we already have this constant.
1600 //
1601 // FIXME, this could be made much more efficient for large constant pools.
1602 int Idx = V->getExistingMachineCPValue(CP: this, Alignment);
1603 if (Idx != -1) {
1604 MachineCPVsSharingEntries.insert(V);
1605 return (unsigned)Idx;
1606 }
1607
1608 Constants.push_back(x: MachineConstantPoolEntry(V, Alignment));
1609 return Constants.size()-1;
1610}
1611
1612void MachineConstantPool::print(raw_ostream &OS) const {
1613 if (Constants.empty()) return;
1614
1615 OS << "Constant Pool:\n";
1616 for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
1617 OS << " cp#" << i << ": ";
1618 if (Constants[i].isMachineConstantPoolEntry())
1619 Constants[i].Val.MachineCPVal->print(O&: OS);
1620 else
1621 Constants[i].Val.ConstVal->printAsOperand(O&: OS, /*PrintType=*/false);
1622 OS << ", align=" << Constants[i].getAlign().value();
1623 OS << "\n";
1624 }
1625}
1626
1627//===----------------------------------------------------------------------===//
1628// Template specialization for MachineFunction implementation of
1629// ProfileSummaryInfo::getEntryCount().
1630//===----------------------------------------------------------------------===//
1631template <>
1632std::optional<Function::ProfileCount>
1633ProfileSummaryInfo::getEntryCount<llvm::MachineFunction>(
1634 const llvm::MachineFunction *F) const {
1635 return F->getFunction().getEntryCount();
1636}
1637
1638#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
1639LLVM_DUMP_METHOD void MachineConstantPool::dump() const { print(dbgs()); }
1640#endif
1641