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