1//===- AsmPrinter.cpp - Common AsmPrinter code ----------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements the AsmPrinter class.
10//
11//===----------------------------------------------------------------------===//
12
13#include "llvm/CodeGen/AsmPrinter.h"
14#include "CodeViewDebug.h"
15#include "DwarfDebug.h"
16#include "DwarfException.h"
17#include "PseudoProbePrinter.h"
18#include "WasmException.h"
19#include "WinCFGuard.h"
20#include "WinException.h"
21#include "llvm/ADT/APFloat.h"
22#include "llvm/ADT/APInt.h"
23#include "llvm/ADT/DenseMap.h"
24#include "llvm/ADT/STLExtras.h"
25#include "llvm/ADT/SmallPtrSet.h"
26#include "llvm/ADT/SmallString.h"
27#include "llvm/ADT/SmallVector.h"
28#include "llvm/ADT/Statistic.h"
29#include "llvm/ADT/StringExtras.h"
30#include "llvm/ADT/StringRef.h"
31#include "llvm/ADT/TinyPtrVector.h"
32#include "llvm/ADT/Twine.h"
33#include "llvm/Analysis/ConstantFolding.h"
34#include "llvm/Analysis/MemoryLocation.h"
35#include "llvm/Analysis/OptimizationRemarkEmitter.h"
36#include "llvm/BinaryFormat/COFF.h"
37#include "llvm/BinaryFormat/Dwarf.h"
38#include "llvm/BinaryFormat/ELF.h"
39#include "llvm/CodeGen/AsmPrinterAnalysis.h"
40#include "llvm/CodeGen/BasicBlockSectionsProfileReader.h"
41#include "llvm/CodeGen/GCMetadata.h"
42#include "llvm/CodeGen/GCMetadataPrinter.h"
43#include "llvm/CodeGen/InsertCodePrefetch.h"
44#include "llvm/CodeGen/LazyMachineBlockFrequencyInfo.h"
45#include "llvm/CodeGen/MachineBasicBlock.h"
46#include "llvm/CodeGen/MachineBlockHashInfo.h"
47#include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
48#include "llvm/CodeGen/MachineConstantPool.h"
49#include "llvm/CodeGen/MachineDominators.h"
50#include "llvm/CodeGen/MachineFrameInfo.h"
51#include "llvm/CodeGen/MachineFunction.h"
52#include "llvm/CodeGen/MachineFunctionPass.h"
53#include "llvm/CodeGen/MachineInstr.h"
54#include "llvm/CodeGen/MachineInstrBundle.h"
55#include "llvm/CodeGen/MachineJumpTableInfo.h"
56#include "llvm/CodeGen/MachineLoopInfo.h"
57#include "llvm/CodeGen/MachineModuleInfo.h"
58#include "llvm/CodeGen/MachineModuleInfoImpls.h"
59#include "llvm/CodeGen/MachineOperand.h"
60#include "llvm/CodeGen/MachineOptimizationRemarkEmitter.h"
61#include "llvm/CodeGen/StackMaps.h"
62#include "llvm/CodeGen/TargetFrameLowering.h"
63#include "llvm/CodeGen/TargetInstrInfo.h"
64#include "llvm/CodeGen/TargetLowering.h"
65#include "llvm/CodeGen/TargetOpcodes.h"
66#include "llvm/CodeGen/TargetRegisterInfo.h"
67#include "llvm/CodeGen/TargetSubtargetInfo.h"
68#include "llvm/Config/config.h"
69#include "llvm/IR/BasicBlock.h"
70#include "llvm/IR/Comdat.h"
71#include "llvm/IR/Constant.h"
72#include "llvm/IR/Constants.h"
73#include "llvm/IR/DataLayout.h"
74#include "llvm/IR/DebugInfoMetadata.h"
75#include "llvm/IR/DerivedTypes.h"
76#include "llvm/IR/EHPersonalities.h"
77#include "llvm/IR/Function.h"
78#include "llvm/IR/GCStrategy.h"
79#include "llvm/IR/GlobalAlias.h"
80#include "llvm/IR/GlobalIFunc.h"
81#include "llvm/IR/GlobalObject.h"
82#include "llvm/IR/GlobalValue.h"
83#include "llvm/IR/GlobalVariable.h"
84#include "llvm/IR/Instruction.h"
85#include "llvm/IR/Instructions.h"
86#include "llvm/IR/LLVMRemarkStreamer.h"
87#include "llvm/IR/Mangler.h"
88#include "llvm/IR/Metadata.h"
89#include "llvm/IR/Module.h"
90#include "llvm/IR/Operator.h"
91#include "llvm/IR/PseudoProbe.h"
92#include "llvm/IR/Type.h"
93#include "llvm/IR/Value.h"
94#include "llvm/IR/ValueHandle.h"
95#include "llvm/MC/MCAsmInfo.h"
96#include "llvm/MC/MCContext.h"
97#include "llvm/MC/MCDirectives.h"
98#include "llvm/MC/MCExpr.h"
99#include "llvm/MC/MCInst.h"
100#include "llvm/MC/MCSchedule.h"
101#include "llvm/MC/MCSection.h"
102#include "llvm/MC/MCSectionCOFF.h"
103#include "llvm/MC/MCSectionELF.h"
104#include "llvm/MC/MCSectionMachO.h"
105#include "llvm/MC/MCSectionXCOFF.h"
106#include "llvm/MC/MCStreamer.h"
107#include "llvm/MC/MCSubtargetInfo.h"
108#include "llvm/MC/MCSymbol.h"
109#include "llvm/MC/MCSymbolELF.h"
110#include "llvm/MC/MCTargetOptions.h"
111#include "llvm/MC/MCValue.h"
112#include "llvm/MC/SectionKind.h"
113#include "llvm/MC/TargetRegistry.h"
114#include "llvm/Object/ELFTypes.h"
115#include "llvm/Pass.h"
116#include "llvm/Remarks/RemarkStreamer.h"
117#include "llvm/Support/Casting.h"
118#include "llvm/Support/CommandLine.h"
119#include "llvm/Support/Compiler.h"
120#include "llvm/Support/ErrorHandling.h"
121#include "llvm/Support/FileSystem.h"
122#include "llvm/Support/Format.h"
123#include "llvm/Support/MathExtras.h"
124#include "llvm/Support/Path.h"
125#include "llvm/Support/VCSRevision.h"
126#include "llvm/Support/VirtualFileSystem.h"
127#include "llvm/Support/raw_ostream.h"
128#include "llvm/Target/TargetLoweringObjectFile.h"
129#include "llvm/Target/TargetMachine.h"
130#include "llvm/Target/TargetOptions.h"
131#include <algorithm>
132#include <cassert>
133#include <cinttypes>
134#include <cstdint>
135#include <iterator>
136#include <memory>
137#include <optional>
138#include <string>
139#include <utility>
140#include <vector>
141
142using namespace llvm;
143
144#define DEBUG_TYPE "asm-printer"
145
146// This is a replication of fields of object::PGOAnalysisMap::Features. It
147// should match the order of the fields so that
148// `object::PGOAnalysisMap::Features::decode(PgoAnalysisMapFeatures.getBits())`
149// succeeds.
150enum class PGOMapFeaturesEnum {
151 None,
152 FuncEntryCount,
153 BBFreq,
154 BrProb,
155 PropellerCFG,
156 All,
157};
158static cl::bits<PGOMapFeaturesEnum> PgoAnalysisMapFeatures(
159 "pgo-analysis-map", cl::Hidden, cl::CommaSeparated,
160 cl::values(
161 clEnumValN(PGOMapFeaturesEnum::None, "none", "Disable all options"),
162 clEnumValN(PGOMapFeaturesEnum::FuncEntryCount, "func-entry-count",
163 "Function Entry Count"),
164 clEnumValN(PGOMapFeaturesEnum::BBFreq, "bb-freq",
165 "Basic Block Frequency"),
166 clEnumValN(PGOMapFeaturesEnum::BrProb, "br-prob", "Branch Probability"),
167 clEnumValN(PGOMapFeaturesEnum::All, "all", "Enable all options")),
168 cl::desc(
169 "Enable extended information within the SHT_LLVM_BB_ADDR_MAP that is "
170 "extracted from PGO related analysis."));
171
172static cl::opt<bool> PgoAnalysisMapEmitBBSectionsCfg(
173 "pgo-analysis-map-emit-bb-sections-cfg",
174 cl::desc("Enable the post-link cfg information from the basic block "
175 "sections profile in the PGO analysis map"),
176 cl::Hidden, cl::init(Val: false));
177
178static cl::opt<bool> BBAddrMapSkipEmitBBEntries(
179 "basic-block-address-map-skip-bb-entries",
180 cl::desc("Skip emitting basic block entries in the SHT_LLVM_BB_ADDR_MAP "
181 "section. It's used to save binary size when BB entries are "
182 "unnecessary for some PGOAnalysisMap features."),
183 cl::Hidden, cl::init(Val: false));
184
185static cl::opt<bool> EmitJumpTableSizesSection(
186 "emit-jump-table-sizes-section",
187 cl::desc("Emit a section containing jump table addresses and sizes"),
188 cl::Hidden, cl::init(Val: false));
189
190// This isn't turned on by default, since several of the scheduling models are
191// not completely accurate, and we don't want to be misleading.
192static cl::opt<bool> PrintLatency(
193 "asm-print-latency",
194 cl::desc("Print instruction latencies as verbose asm comments"), cl::Hidden,
195 cl::init(Val: false));
196
197static cl::opt<std::string>
198 StackUsageFile("stack-usage-file",
199 cl::desc("Output filename for stack usage information"),
200 cl::value_desc("filename"), cl::Hidden);
201
202extern cl::opt<bool> EmitBBHash;
203
204STATISTIC(EmittedInsts, "Number of machine instrs printed");
205
206char AsmPrinter::ID = 0;
207
208namespace {
209class AddrLabelMapCallbackPtr final : CallbackVH {
210 AddrLabelMap *Map = nullptr;
211
212public:
213 AddrLabelMapCallbackPtr() = default;
214 AddrLabelMapCallbackPtr(Value *V) : CallbackVH(V) {}
215
216 void setPtr(BasicBlock *BB) {
217 ValueHandleBase::operator=(RHS: BB);
218 }
219
220 void setMap(AddrLabelMap *map) { Map = map; }
221
222 void deleted() override;
223 void allUsesReplacedWith(Value *V2) override;
224};
225} // namespace
226
227class llvm::AddrLabelMap {
228 MCContext &Context;
229 struct AddrLabelSymEntry {
230 /// The symbols for the label.
231 TinyPtrVector<MCSymbol *> Symbols;
232
233 Function *Fn; // The containing function of the BasicBlock.
234 unsigned Index; // The index in BBCallbacks for the BasicBlock.
235 };
236
237 DenseMap<AssertingVH<BasicBlock>, AddrLabelSymEntry> AddrLabelSymbols;
238
239 /// Callbacks for the BasicBlock's that we have entries for. We use this so
240 /// we get notified if a block is deleted or RAUWd.
241 std::vector<AddrLabelMapCallbackPtr> BBCallbacks;
242
243 /// This is a per-function list of symbols whose corresponding BasicBlock got
244 /// deleted. These symbols need to be emitted at some point in the file, so
245 /// AsmPrinter emits them after the function body.
246 DenseMap<AssertingVH<Function>, std::vector<MCSymbol *>>
247 DeletedAddrLabelsNeedingEmission;
248
249public:
250 AddrLabelMap(MCContext &context) : Context(context) {}
251
252 ~AddrLabelMap() {
253 assert(DeletedAddrLabelsNeedingEmission.empty() &&
254 "Some labels for deleted blocks never got emitted");
255 }
256
257 ArrayRef<MCSymbol *> getAddrLabelSymbolToEmit(BasicBlock *BB);
258
259 void takeDeletedSymbolsForFunction(Function *F,
260 std::vector<MCSymbol *> &Result);
261
262 void UpdateForDeletedBlock(BasicBlock *BB);
263 void UpdateForRAUWBlock(BasicBlock *Old, BasicBlock *New);
264};
265
266ArrayRef<MCSymbol *> AddrLabelMap::getAddrLabelSymbolToEmit(BasicBlock *BB) {
267 assert(BB->hasAddressTaken() &&
268 "Shouldn't get label for block without address taken");
269 AddrLabelSymEntry &Entry = AddrLabelSymbols[BB];
270
271 // If we already had an entry for this block, just return it.
272 if (!Entry.Symbols.empty()) {
273 assert(BB->getParent() == Entry.Fn && "Parent changed");
274 return Entry.Symbols;
275 }
276
277 // Otherwise, this is a new entry, create a new symbol for it and add an
278 // entry to BBCallbacks so we can be notified if the BB is deleted or RAUWd.
279 BBCallbacks.emplace_back(args&: BB);
280 BBCallbacks.back().setMap(this);
281 Entry.Index = BBCallbacks.size() - 1;
282 Entry.Fn = BB->getParent();
283 MCSymbol *Sym = BB->hasAddressTaken() ? Context.createNamedTempSymbol()
284 : Context.createTempSymbol();
285 Entry.Symbols.push_back(NewVal: Sym);
286 return Entry.Symbols;
287}
288
289/// If we have any deleted symbols for F, return them.
290void AddrLabelMap::takeDeletedSymbolsForFunction(
291 Function *F, std::vector<MCSymbol *> &Result) {
292 DenseMap<AssertingVH<Function>, std::vector<MCSymbol *>>::iterator I =
293 DeletedAddrLabelsNeedingEmission.find(Val: F);
294
295 // If there are no entries for the function, just return.
296 if (I == DeletedAddrLabelsNeedingEmission.end())
297 return;
298
299 // Otherwise, take the list.
300 std::swap(x&: Result, y&: I->second);
301 DeletedAddrLabelsNeedingEmission.erase(I);
302}
303
304//===- Address of Block Management ----------------------------------------===//
305
306ArrayRef<MCSymbol *>
307AsmPrinter::getAddrLabelSymbolToEmit(const BasicBlock *BB) {
308 // Lazily create AddrLabelSymbols.
309 if (!AddrLabelSymbols)
310 AddrLabelSymbols = std::make_unique<AddrLabelMap>(args&: OutContext);
311 return AddrLabelSymbols->getAddrLabelSymbolToEmit(
312 BB: const_cast<BasicBlock *>(BB));
313}
314
315void AsmPrinter::takeDeletedSymbolsForFunction(
316 const Function *F, std::vector<MCSymbol *> &Result) {
317 // If no blocks have had their addresses taken, we're done.
318 if (!AddrLabelSymbols)
319 return;
320 return AddrLabelSymbols->takeDeletedSymbolsForFunction(
321 F: const_cast<Function *>(F), Result);
322}
323
324void AddrLabelMap::UpdateForDeletedBlock(BasicBlock *BB) {
325 // If the block got deleted, there is no need for the symbol. If the symbol
326 // was already emitted, we can just forget about it, otherwise we need to
327 // queue it up for later emission when the function is output.
328 AddrLabelSymEntry Entry = std::move(AddrLabelSymbols[BB]);
329 AddrLabelSymbols.erase(Val: BB);
330 assert(!Entry.Symbols.empty() && "Didn't have a symbol, why a callback?");
331 BBCallbacks[Entry.Index] = nullptr; // Clear the callback.
332
333#if !LLVM_MEMORY_SANITIZER_BUILD
334 // BasicBlock is destroyed already, so this access is UB detectable by msan.
335 assert((BB->getParent() == nullptr || BB->getParent() == Entry.Fn) &&
336 "Block/parent mismatch");
337#endif
338
339 for (MCSymbol *Sym : Entry.Symbols) {
340 if (Sym->isDefined())
341 return;
342
343 // If the block is not yet defined, we need to emit it at the end of the
344 // function. Add the symbol to the DeletedAddrLabelsNeedingEmission list
345 // for the containing Function. Since the block is being deleted, its
346 // parent may already be removed, we have to get the function from 'Entry'.
347 DeletedAddrLabelsNeedingEmission[Entry.Fn].push_back(x: Sym);
348 }
349}
350
351void AddrLabelMap::UpdateForRAUWBlock(BasicBlock *Old, BasicBlock *New) {
352 // Get the entry for the RAUW'd block and remove it from our map.
353 AddrLabelSymEntry OldEntry = std::move(AddrLabelSymbols[Old]);
354 AddrLabelSymbols.erase(Val: Old);
355 assert(!OldEntry.Symbols.empty() && "Didn't have a symbol, why a callback?");
356
357 AddrLabelSymEntry &NewEntry = AddrLabelSymbols[New];
358
359 // If New is not address taken, just move our symbol over to it.
360 if (NewEntry.Symbols.empty()) {
361 BBCallbacks[OldEntry.Index].setPtr(New); // Update the callback.
362 NewEntry = std::move(OldEntry); // Set New's entry.
363 return;
364 }
365
366 BBCallbacks[OldEntry.Index] = nullptr; // Update the callback.
367
368 // Otherwise, we need to add the old symbols to the new block's set.
369 llvm::append_range(C&: NewEntry.Symbols, R&: OldEntry.Symbols);
370}
371
372void AddrLabelMapCallbackPtr::deleted() {
373 Map->UpdateForDeletedBlock(BB: cast<BasicBlock>(Val: getValPtr()));
374}
375
376void AddrLabelMapCallbackPtr::allUsesReplacedWith(Value *V2) {
377 Map->UpdateForRAUWBlock(Old: cast<BasicBlock>(Val: getValPtr()), New: cast<BasicBlock>(Val: V2));
378}
379
380/// getGVAlignment - Return the alignment to use for the specified global
381/// value. This rounds up to the preferred alignment if possible and legal.
382Align AsmPrinter::getGVAlignment(const GlobalObject *GV, const DataLayout &DL,
383 Align InAlign) {
384 Align Alignment;
385 if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(Val: GV))
386 Alignment = DL.getPreferredAlign(GV: GVar);
387
388 // If InAlign is specified, round it to it.
389 if (InAlign > Alignment)
390 Alignment = InAlign;
391
392 // If the GV has a specified alignment, take it into account.
393 MaybeAlign GVAlign;
394 if (auto *GVar = dyn_cast<GlobalVariable>(Val: GV))
395 GVAlign = GVar->getAlign();
396 else if (auto *F = dyn_cast<Function>(Val: GV))
397 GVAlign = F->getAlign();
398 if (!GVAlign)
399 return Alignment;
400
401 assert(GVAlign && "GVAlign must be set");
402
403 // If the GVAlign is larger than NumBits, or if we are required to obey
404 // NumBits because the GV has an assigned section, obey it.
405 if (*GVAlign > Alignment || GV->hasSection())
406 Alignment = *GVAlign;
407 return Alignment;
408}
409
410AsmPrinter::AsmPrinter(TargetMachine &tm, std::unique_ptr<MCStreamer> Streamer,
411 char &ID)
412 : MachineFunctionPass(ID), TM(tm), MAI(tm.getMCAsmInfo()),
413 OutContext(Streamer->getContext()), OutStreamer(std::move(Streamer)),
414 SM(*this) {
415 VerboseAsm = OutStreamer->isVerboseAsm();
416 DwarfUsesRelocationsAcrossSections =
417 MAI.doesDwarfUseRelocationsAcrossSections();
418 GetMMI = [this]() {
419 auto *MMIWP = getAnalysisIfAvailable<MachineModuleInfoWrapperPass>();
420 return MMIWP ? &MMIWP->getMMI() : nullptr;
421 };
422 GetORE = [this](MachineFunction &MF) {
423 return &getAnalysis<MachineOptimizationRemarkEmitterPass>().getORE();
424 };
425 GetMDT = [this](MachineFunction &MF) {
426 auto *MDTWrapper =
427 getAnalysisIfAvailable<MachineDominatorTreeWrapperPass>();
428 return MDTWrapper ? &MDTWrapper->getDomTree() : nullptr;
429 };
430 GetMLI = [this](MachineFunction &MF) {
431 auto *MLIWrapper = getAnalysisIfAvailable<MachineLoopInfoWrapperPass>();
432 return MLIWrapper ? &MLIWrapper->getLI() : nullptr;
433 };
434 BeginGCAssembly = [this](Module &M) {
435 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
436 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
437 for (const auto &I : *MI)
438 if (GCMetadataPrinter *MP = getOrCreateGCPrinter(S&: *I))
439 MP->beginAssembly(M, Info&: *MI, AP&: *this);
440 };
441 FinishGCAssembly = [this](Module &M) {
442 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
443 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
444 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E;)
445 if (GCMetadataPrinter *MP = getOrCreateGCPrinter(S&: **--I))
446 MP->finishAssembly(M, Info&: *MI, AP&: *this);
447 };
448 EmitStackMaps = [this](Module &M) {
449 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
450 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
451 bool NeedsDefault = false;
452 if (MI->begin() == MI->end())
453 // No GC strategy, use the default format.
454 NeedsDefault = true;
455 else
456 for (const auto &I : *MI) {
457 if (GCMetadataPrinter *MP = getOrCreateGCPrinter(S&: *I))
458 if (MP->emitStackMaps(SM, AP&: *this))
459 continue;
460 // The strategy doesn't have printer or doesn't emit custom stack maps.
461 // Use the default format.
462 NeedsDefault = true;
463 }
464
465 if (NeedsDefault)
466 SM.serializeToStackMapSection();
467 };
468 AssertDebugEHFinalized = [&]() {
469 assert(!DD && Handlers.size() == NumUserHandlers &&
470 "Debug/EH info didn't get finalized");
471 };
472}
473
474AsmPrinter::~AsmPrinter() { AssertDebugEHFinalized(); }
475
476bool AsmPrinter::isPositionIndependent() const {
477 return TM.isPositionIndependent();
478}
479
480/// getFunctionNumber - Return a unique ID for the current function.
481unsigned AsmPrinter::getFunctionNumber() const {
482 return MF->getFunctionNumber();
483}
484
485const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
486 return *TM.getObjFileLowering();
487}
488
489const DataLayout &AsmPrinter::getDataLayout() const {
490 assert(MMI && "MMI could not be nullptr!");
491 return MMI->getModule()->getDataLayout();
492}
493
494// Do not use the cached DataLayout because some client use it without a Module
495// (dsymutil, llvm-dwarfdump).
496unsigned AsmPrinter::getPointerSize() const {
497 return TM.getPointerSize(AS: 0); // FIXME: Default address space
498}
499
500const MCSubtargetInfo &AsmPrinter::getSubtargetInfo() const {
501 assert(MF && "getSubtargetInfo requires a valid MachineFunction!");
502 return MF->getSubtarget<MCSubtargetInfo>();
503}
504
505void AsmPrinter::EmitToStreamer(MCStreamer &S, const MCInst &Inst) {
506 S.emitInstruction(Inst, STI: getSubtargetInfo());
507}
508
509/// getCurrentSection() - Return the current section we are emitting to.
510const MCSection *AsmPrinter::getCurrentSection() const {
511 return OutStreamer->getCurrentSectionOnly();
512}
513
514/// createDwarfDebug() - Create the DwarfDebug handler.
515DwarfDebug *AsmPrinter::createDwarfDebug() { return new DwarfDebug(this); }
516
517void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
518 AU.setPreservesAll();
519 MachineFunctionPass::getAnalysisUsage(AU);
520 AU.addRequired<MachineOptimizationRemarkEmitterPass>();
521 AU.addRequired<GCModuleInfo>();
522 AU.addRequired<LazyMachineBlockFrequencyInfoPass>();
523 AU.addRequired<MachineBranchProbabilityInfoWrapperPass>();
524 if (EmitBBHash)
525 AU.addRequired<MachineBlockHashInfo>();
526 AU.addUsedIfAvailable<BasicBlockSectionsProfileReaderWrapperPass>();
527}
528
529bool AsmPrinter::doInitialization(Module &M) {
530 MMI = GetMMI();
531 HasSplitStack = false;
532 HasNoSplitStack = false;
533 DbgInfoAvailable = !M.debug_compile_units().empty();
534 const Triple &Target = TM.getTargetTriple();
535
536 AddrLabelSymbols = nullptr;
537
538 // Initialize TargetLoweringObjectFile.
539 TM.getObjFileLowering()->Initialize(ctx&: OutContext, TM);
540
541 TM.getObjFileLowering()->getModuleMetadata(M);
542
543 // On AIX, we delay emitting any section information until
544 // after emitting the .file pseudo-op. This allows additional
545 // information (such as the embedded command line) to be associated
546 // with all sections in the object file rather than a single section.
547 if (!Target.isOSBinFormatXCOFF())
548 OutStreamer->initSections(STI: TM.getMCSubtargetInfo());
549
550 // Emit the version-min deployment target directive if needed.
551 //
552 // FIXME: If we end up with a collection of these sorts of Darwin-specific
553 // or ELF-specific things, it may make sense to have a platform helper class
554 // that will work with the target helper class. For now keep it here, as the
555 // alternative is duplicated code in each of the target asm printers that
556 // use the directive, where it would need the same conditionalization
557 // anyway.
558 if (Target.isOSBinFormatMachO() && Target.isOSDarwin()) {
559 Triple TVT(M.getDarwinTargetVariantTriple());
560 OutStreamer->emitVersionForTarget(
561 Target, SDKVersion: M.getSDKVersion(),
562 DarwinTargetVariantTriple: M.getDarwinTargetVariantTriple().empty() ? nullptr : &TVT,
563 DarwinTargetVariantSDKVersion: M.getDarwinTargetVariantSDKVersion());
564 }
565
566 // Allow the target to emit any magic that it wants at the start of the file.
567 emitStartOfAsmFile(M);
568
569 // Very minimal debug info. It is ignored if we emit actual debug info. If we
570 // don't, this at least helps the user find where a global came from.
571 if (MAI.hasSingleParameterDotFile()) {
572 // .file "foo.c"
573 if (MAI.isAIX()) {
574 const char VerStr[] =
575#ifdef PACKAGE_VENDOR
576 PACKAGE_VENDOR " "
577#endif
578 PACKAGE_NAME " version " PACKAGE_VERSION
579#ifdef LLVM_REVISION
580 " (" LLVM_REVISION ")"
581#endif
582 ;
583 // TODO: Add timestamp and description.
584 OutStreamer->emitFileDirective(Filename: M.getSourceFileName(), CompilerVersion: VerStr, TimeStamp: "", Description: "");
585 } else {
586 OutStreamer->emitFileDirective(
587 Filename: llvm::sys::path::filename(path: M.getSourceFileName()));
588 }
589 }
590
591 // On AIX, emit bytes for llvm.commandline metadata after .file so that the
592 // C_INFO symbol is preserved if any csect is kept by the linker.
593 if (Target.isOSBinFormatXCOFF()) {
594 emitModuleCommandLines(M);
595 // Now we can generate section information.
596 OutStreamer->switchSection(
597 Section: OutContext.getObjectFileInfo()->getTextSection());
598
599 // To work around an AIX assembler and/or linker bug, generate
600 // a rename for the default text-section symbol name. This call has
601 // no effect when generating object code directly.
602 MCSection *TextSection =
603 OutStreamer->getContext().getObjectFileInfo()->getTextSection();
604 MCSymbolXCOFF *XSym =
605 static_cast<MCSectionXCOFF *>(TextSection)->getQualNameSymbol();
606 if (XSym->hasRename())
607 OutStreamer->emitXCOFFRenameDirective(Name: XSym, Rename: XSym->getSymbolTableName());
608 }
609
610 BeginGCAssembly(M);
611
612 // Emit module-level inline asm if it exists.
613 if (M.hasModuleInlineAsm()) {
614 OutStreamer->AddComment(T: "Start of file scope inline assembly");
615 OutStreamer->addBlankLine();
616 for (const Module::GlobalAsmFragment &Frag : M.getModuleInlineAsm()) {
617 const MCSubtargetInfo &AsmSTI = TM.getMCSubtargetInfo(
618 CPU: Frag.Props.TargetCPU, FS: Frag.Props.TargetFeatures);
619 bool DidPush = emitTargetFeaturePush(STI: AsmSTI);
620 emitInlineAsm(
621 Str: Frag.Asm, STI: AsmSTI, MCOptions: TM.Options.MCOptions, LocMDNode: nullptr,
622 AsmDialect: InlineAsm::AsmDialect(TM.getMCAsmInfo().getAssemblerDialect()));
623 emitTargetFeaturePop(STI: AsmSTI, DidPush);
624 }
625 OutStreamer->AddComment(T: "End of file scope inline assembly");
626 OutStreamer->addBlankLine();
627 }
628
629 if (MAI.doesSupportDebugInformation()) {
630 bool EmitCodeView = M.getCodeViewFlag();
631 // On Windows targets, emit minimal CodeView compiler info even when debug
632 // info is disabled.
633 if ((Target.isOSWindows() || (Target.isUEFI() && EmitCodeView)) &&
634 M.getNamedMetadata(Name: "llvm.dbg.cu"))
635 Handlers.push_back(Elt: std::make_unique<CodeViewDebug>(args: this));
636 if (!EmitCodeView || M.getDwarfVersion()) {
637 if (hasDebugInfo()) {
638 DD = createDwarfDebug();
639 Handlers.push_back(Elt: std::unique_ptr<DwarfDebug>(DD));
640 }
641 }
642 }
643
644 if (M.getNamedMetadata(Name: PseudoProbeDescMetadataName))
645 PP = std::make_unique<PseudoProbeHandler>(args: this);
646
647 switch (MAI.getExceptionHandlingType()) {
648 case ExceptionHandling::None:
649 // We may want to emit CFI for debug.
650 [[fallthrough]];
651 case ExceptionHandling::SjLj:
652 case ExceptionHandling::DwarfCFI:
653 case ExceptionHandling::ARM:
654 for (auto &F : M.getFunctionList()) {
655 if (getFunctionCFISectionType(F) != CFISection::None)
656 ModuleCFISection = getFunctionCFISectionType(F);
657 // If any function needsUnwindTableEntry(), it needs .eh_frame and hence
658 // the module needs .eh_frame. If we have found that case, we are done.
659 if (ModuleCFISection == CFISection::EH)
660 break;
661 }
662 assert(MAI.getExceptionHandlingType() == ExceptionHandling::DwarfCFI ||
663 usesCFIWithoutEH() || ModuleCFISection != CFISection::EH);
664 break;
665 default:
666 break;
667 }
668
669 EHStreamer *ES = nullptr;
670 switch (MAI.getExceptionHandlingType()) {
671 case ExceptionHandling::Default:
672 llvm_unreachable("should have resolved exception model kind");
673 case ExceptionHandling::None:
674 case ExceptionHandling::Emscripten:
675 // Emscripten EH is handled in JS glue code and emits no EH tables here.
676 if (!usesCFIWithoutEH())
677 break;
678 [[fallthrough]];
679 case ExceptionHandling::SjLj:
680 case ExceptionHandling::DwarfCFI:
681 case ExceptionHandling::ZOS:
682 ES = new DwarfCFIException(this);
683 break;
684 case ExceptionHandling::ARM:
685 ES = new ARMException(this);
686 break;
687 case ExceptionHandling::WinEH:
688 switch (MAI.getWinEHEncodingType()) {
689 default: llvm_unreachable("unsupported unwinding information encoding");
690 case WinEH::EncodingType::Invalid:
691 break;
692 case WinEH::EncodingType::X86:
693 case WinEH::EncodingType::Itanium:
694 ES = new WinException(this);
695 break;
696 }
697 break;
698 case ExceptionHandling::Wasm:
699 ES = new WasmException(this);
700 break;
701 case ExceptionHandling::AIX:
702 ES = new AIXException(this);
703 break;
704 }
705 if (ES)
706 EHHandlers.push_back(Elt: std::unique_ptr<EHStreamer>(ES));
707
708 // All CFG modes required the tables emitted.
709 if (M.getControlFlowGuardMode() != ControlFlowGuardMode::Disabled)
710 Handlers.push_back(Elt: std::make_unique<WinCFGuard>(args: this));
711
712 for (auto &Handler : Handlers)
713 Handler->beginModule(M: &M);
714 for (auto &Handler : EHHandlers)
715 Handler->beginModule(M: &M);
716
717 return false;
718}
719
720static bool canBeHidden(const GlobalValue *GV, const MCAsmInfo &MAI) {
721 if (!MAI.hasWeakDefCanBeHiddenDirective())
722 return false;
723
724 return GV->canBeOmittedFromSymbolTable();
725}
726
727void AsmPrinter::emitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const {
728 GlobalValue::LinkageTypes Linkage = GV->getLinkage();
729 switch (Linkage) {
730 case GlobalValue::CommonLinkage:
731 case GlobalValue::LinkOnceAnyLinkage:
732 case GlobalValue::LinkOnceODRLinkage:
733 case GlobalValue::WeakAnyLinkage:
734 case GlobalValue::WeakODRLinkage:
735 if (MAI.isMachO()) {
736 // .globl _foo
737 OutStreamer->emitSymbolAttribute(Symbol: GVSym, Attribute: MCSA_Global);
738
739 if (!canBeHidden(GV, MAI))
740 // .weak_definition _foo
741 OutStreamer->emitSymbolAttribute(Symbol: GVSym, Attribute: MCSA_WeakDefinition);
742 else
743 OutStreamer->emitSymbolAttribute(Symbol: GVSym, Attribute: MCSA_WeakDefAutoPrivate);
744 } else if (MAI.avoidWeakIfComdat() && GV->hasComdat()) {
745 // .globl _foo
746 OutStreamer->emitSymbolAttribute(Symbol: GVSym, Attribute: MCSA_Global);
747 //NOTE: linkonce is handled by the section the symbol was assigned to.
748 } else {
749 // .weak _foo
750 OutStreamer->emitSymbolAttribute(Symbol: GVSym, Attribute: MCSA_Weak);
751 }
752 return;
753 case GlobalValue::ExternalLinkage:
754 OutStreamer->emitSymbolAttribute(Symbol: GVSym, Attribute: MCSA_Global);
755 return;
756 case GlobalValue::PrivateLinkage:
757 case GlobalValue::InternalLinkage:
758 return;
759 case GlobalValue::ExternalWeakLinkage:
760 case GlobalValue::AvailableExternallyLinkage:
761 case GlobalValue::AppendingLinkage:
762 llvm_unreachable("Should never emit this");
763 }
764 llvm_unreachable("Unknown linkage type!");
765}
766
767void AsmPrinter::getNameWithPrefix(SmallVectorImpl<char> &Name,
768 const GlobalValue *GV) const {
769 TM.getNameWithPrefix(Name, GV, Mang&: getObjFileLowering().getMangler());
770}
771
772MCSymbol *AsmPrinter::getSymbol(const GlobalValue *GV) const {
773 return TM.getSymbol(GV);
774}
775
776MCSymbol *AsmPrinter::getSymbolPreferLocal(const GlobalValue &GV) const {
777 // On ELF, use .Lfoo$local if GV is a non-interposable GlobalObject with an
778 // exact definion (intersection of GlobalValue::hasExactDefinition() and
779 // !isInterposable()). These linkages include: external, appending, internal,
780 // private. It may be profitable to use a local alias for external. The
781 // assembler would otherwise be conservative and assume a global default
782 // visibility symbol can be interposable, even if the code generator already
783 // assumed it.
784 if (TM.getTargetTriple().isOSBinFormatELF() && GV.canBenefitFromLocalAlias()) {
785 const Module &M = *GV.getParent();
786 if (TM.getRelocationModel() != Reloc::Static &&
787 M.getPIELevel() == PIELevel::Default && GV.isDSOLocal())
788 return getSymbolWithGlobalValueBase(GV: &GV, Suffix: "$local");
789 }
790 return TM.getSymbol(GV: &GV);
791}
792
793/// EmitGlobalVariable - Emit the specified global variable to the .s file.
794void AsmPrinter::emitGlobalVariable(const GlobalVariable *GV) {
795 MaybeAlign AlignmentGranule = getRequiredGlobalAlignmentGranule(GV: *GV);
796 emitGlobalVariable(GV, AlignmentGranule);
797 if (AlignmentGranule)
798 OutStreamer->emitValueToAlignment(Alignment: *AlignmentGranule);
799}
800
801void AsmPrinter::emitGlobalVariable(const GlobalVariable *GV,
802 MaybeAlign AlignmentGranule) {
803 bool IsEmuTLSVar = TM.useEmulatedTLS() && GV->isThreadLocal();
804 assert(!(IsEmuTLSVar && GV->hasCommonLinkage()) &&
805 "No emulated TLS variables in the common section");
806
807 // Never emit TLS variable xyz in emulated TLS model.
808 // The initialization value is in __emutls_t.xyz instead of xyz.
809 if (IsEmuTLSVar)
810 return;
811
812 if (GV->hasInitializer()) {
813 // Check to see if this is a special global used by LLVM, if so, emit it.
814 if (emitSpecialLLVMGlobal(GV))
815 return;
816
817 // Skip the emission of global equivalents. The symbol can be emitted later
818 // on by emitGlobalGOTEquivs in case it turns out to be needed.
819 if (GlobalGOTEquivs.count(Key: getSymbol(GV)))
820 return;
821
822 if (isVerbose()) {
823 // When printing the control variable __emutls_v.*,
824 // we don't need to print the original TLS variable name.
825 GV->printAsOperand(O&: OutStreamer->getCommentOS(),
826 /*PrintType=*/false, M: GV->getParent());
827 OutStreamer->getCommentOS() << '\n';
828 }
829 }
830
831 MCSymbol *GVSym = getSymbol(GV);
832 MCSymbol *EmittedSym = GVSym;
833
834 // getOrCreateEmuTLSControlSym only creates the symbol with name and default
835 // attributes.
836 // GV's or GVSym's attributes will be used for the EmittedSym.
837 emitVisibility(Sym: EmittedSym, Visibility: GV->getVisibility(), IsDefinition: !GV->isDeclaration());
838
839 if (GV->isTagged()) {
840 Triple T = TM.getTargetTriple();
841
842 if (T.getArch() != Triple::aarch64)
843 OutContext.reportError(L: SMLoc(),
844 Msg: "tagged symbols (-fsanitize=memtag-globals) are "
845 "only supported on AArch64");
846 OutStreamer->emitSymbolAttribute(Symbol: EmittedSym, Attribute: MCSA_Memtag);
847 }
848
849 if (!GV->hasInitializer()) // External globals require no extra code.
850 return;
851
852 GVSym->redefineIfPossible();
853 if (GVSym->isDefined() || GVSym->isVariable())
854 OutContext.reportError(L: SMLoc(), Msg: "symbol '" + Twine(GVSym->getName()) +
855 "' is already defined");
856
857 if (MAI.hasDotTypeDotSizeDirective())
858 OutStreamer->emitSymbolAttribute(Symbol: EmittedSym, Attribute: MCSA_ELF_TypeObject);
859
860 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GO: GV, TM);
861
862 const DataLayout &DL = GV->getDataLayout();
863 uint64_t Size = GV->getGlobalSize(DL);
864
865 // If the alignment is specified, we *must* obey it. Overaligning a global
866 // with a specified alignment is a prompt way to break globals emitted to
867 // sections and expected to be contiguous (e.g. ObjC metadata).
868 //
869 // If we get passed in an explicit alignment granule, it is up to the caller
870 // to ensure that is not the case (i.e. that the GV is not in a section).
871 Align Alignment = getGVAlignment(GV, DL);
872
873 if (AlignmentGranule) {
874 assert(!GV->hasSection());
875 Size = alignTo(Size, A: *AlignmentGranule);
876 if (Alignment < *AlignmentGranule)
877 Alignment = *AlignmentGranule;
878 }
879
880 for (auto &Handler : Handlers)
881 Handler->setSymbolSize(Sym: GVSym, Size);
882
883 // Handle common symbols
884 if (GVKind.isCommon()) {
885 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
886 // .comm _foo, 42, 4
887 OutStreamer->emitCommonSymbol(Symbol: GVSym, Size, ByteAlignment: Alignment);
888 return;
889 }
890
891 // Determine to which section this global should be emitted.
892 MCSection *TheSection = getObjFileLowering().SectionForGlobal(GO: GV, Kind: GVKind, TM);
893
894 // If we have a bss global going to a section that supports the
895 // zerofill directive, do so here.
896 if (GVKind.isBSS() && MAI.isMachO() && TheSection->isBssSection()) {
897 if (Size == 0)
898 Size = 1; // zerofill of 0 bytes is undefined.
899 emitLinkage(GV, GVSym);
900 // .zerofill __DATA, __bss, _foo, 400, 5
901 OutStreamer->emitZerofill(Section: TheSection, Symbol: GVSym, Size, ByteAlignment: Alignment);
902 return;
903 }
904
905 // If this is a BSS local symbol and we are emitting in the BSS
906 // section use .lcomm/.comm directive.
907 if (GVKind.isBSSLocal() &&
908 getObjFileLowering().getBSSSection() == TheSection) {
909 if (Size == 0)
910 Size = 1; // .comm Foo, 0 is undefined, avoid it.
911
912 // Use .lcomm only if it supports user-specified alignment.
913 // Otherwise, while it would still be correct to use .lcomm in some
914 // cases (e.g. when Align == 1), the external assembler might enfore
915 // some -unknown- default alignment behavior, which could cause
916 // spurious differences between external and integrated assembler.
917 // Prefer to simply fall back to .local / .comm in this case.
918 if (MAI.getLCOMMDirectiveAlignmentType() != LCOMM::NoAlignment) {
919 // .lcomm _foo, 42
920 OutStreamer->emitLocalCommonSymbol(Symbol: GVSym, Size, ByteAlignment: Alignment);
921 return;
922 }
923
924 // .local _foo
925 OutStreamer->emitSymbolAttribute(Symbol: GVSym, Attribute: MCSA_Local);
926 // .comm _foo, 42, 4
927 OutStreamer->emitCommonSymbol(Symbol: GVSym, Size, ByteAlignment: Alignment);
928 return;
929 }
930
931 // Handle thread local data for mach-o which requires us to output an
932 // additional structure of data and mangle the original symbol so that we
933 // can reference it later.
934 //
935 // TODO: This should become an "emit thread local global" method on TLOF.
936 // All of this macho specific stuff should be sunk down into TLOFMachO and
937 // stuff like "TLSExtraDataSection" should no longer be part of the parent
938 // TLOF class. This will also make it more obvious that stuff like
939 // MCStreamer::EmitTBSSSymbol is macho specific and only called from macho
940 // specific code.
941 if (GVKind.isThreadLocal() && MAI.isMachO()) {
942 // Emit the .tbss symbol
943 MCSymbol *MangSym =
944 OutContext.getOrCreateSymbol(Name: GVSym->getName() + Twine("$tlv$init"));
945
946 if (GVKind.isThreadBSS()) {
947 TheSection = getObjFileLowering().getTLSBSSSection();
948 OutStreamer->emitTBSSSymbol(Section: TheSection, Symbol: MangSym, Size, ByteAlignment: Alignment);
949 } else if (GVKind.isThreadData()) {
950 OutStreamer->switchSection(Section: TheSection);
951
952 emitAlignment(Alignment, GV);
953 OutStreamer->emitLabel(Symbol: MangSym);
954
955 emitGlobalConstant(DL: GV->getDataLayout(),
956 CV: GV->getInitializer());
957 }
958
959 OutStreamer->addBlankLine();
960
961 // Emit the variable struct for the runtime.
962 MCSection *TLVSect = getObjFileLowering().getTLSExtraDataSection();
963
964 OutStreamer->switchSection(Section: TLVSect);
965 // Emit the linkage here.
966 emitLinkage(GV, GVSym);
967 OutStreamer->emitLabel(Symbol: GVSym);
968
969 // Three pointers in size:
970 // - __tlv_bootstrap - used to make sure support exists
971 // - spare pointer, used when mapped by the runtime
972 // - pointer to mangled symbol above with initializer
973 unsigned PtrSize = DL.getPointerTypeSize(Ty: GV->getType());
974 OutStreamer->emitSymbolValue(Sym: GetExternalSymbolSymbol(Sym: "_tlv_bootstrap"),
975 Size: PtrSize);
976 OutStreamer->emitIntValue(Value: 0, Size: PtrSize);
977 OutStreamer->emitSymbolValue(Sym: MangSym, Size: PtrSize);
978
979 OutStreamer->addBlankLine();
980 return;
981 }
982
983 MCSymbol *EmittedInitSym = GVSym;
984
985 OutStreamer->switchSection(Section: TheSection);
986
987 emitLinkage(GV, GVSym: EmittedInitSym);
988 emitAlignment(Alignment, GV);
989
990 OutStreamer->emitLabel(Symbol: EmittedInitSym);
991 MCSymbol *LocalAlias = getSymbolPreferLocal(GV: *GV);
992 if (LocalAlias != EmittedInitSym)
993 OutStreamer->emitLabel(Symbol: LocalAlias);
994
995 emitGlobalConstant(DL: GV->getDataLayout(), CV: GV->getInitializer());
996
997 if (MAI.hasDotTypeDotSizeDirective())
998 // .size foo, 42
999 OutStreamer->emitELFSize(Symbol: EmittedInitSym,
1000 Value: MCConstantExpr::create(Value: Size, Ctx&: OutContext));
1001
1002 OutStreamer->addBlankLine();
1003}
1004
1005/// Emit the directive and value for debug thread local expression
1006///
1007/// \p Value - The value to emit.
1008/// \p Size - The size of the integer (in bytes) to emit.
1009void AsmPrinter::emitDebugValue(const MCExpr *Value, unsigned Size) const {
1010 OutStreamer->emitValue(Value, Size);
1011}
1012
1013void AsmPrinter::emitFunctionHeaderComment() {}
1014
1015void AsmPrinter::emitFunctionPrefix(ArrayRef<const Constant *> Prefix) {
1016 const Function &F = MF->getFunction();
1017 if (!MAI.hasSubsectionsViaSymbols()) {
1018 for (auto &C : Prefix)
1019 emitGlobalConstant(DL: F.getDataLayout(), CV: C);
1020 return;
1021 }
1022 // Preserving prefix-like data on platforms which use subsections-via-symbols
1023 // is a bit tricky. Here we introduce a symbol for the prefix-like data
1024 // and use the .alt_entry attribute to mark the function's real entry point
1025 // as an alternative entry point to the symbol that precedes the function..
1026 OutStreamer->emitLabel(Symbol: OutContext.createLinkerPrivateTempSymbol());
1027
1028 for (auto &C : Prefix) {
1029 emitGlobalConstant(DL: F.getDataLayout(), CV: C);
1030 }
1031
1032 // Emit an .alt_entry directive for the actual function symbol.
1033 OutStreamer->emitSymbolAttribute(Symbol: CurrentFnSym, Attribute: MCSA_AltEntry);
1034}
1035
1036/// EmitFunctionHeader - This method emits the header for the current
1037/// function.
1038void AsmPrinter::emitFunctionHeader() {
1039 const Function &F = MF->getFunction();
1040
1041 if (isVerbose())
1042 OutStreamer->getCommentOS()
1043 << "-- Begin function "
1044 << GlobalValue::dropLLVMManglingEscape(Name: F.getName()) << '\n';
1045
1046 // Print out constants referenced by the function
1047 emitConstantPool();
1048
1049 // Print the 'header' of function.
1050 // If basic block sections are desired, explicitly request a unique section
1051 // for this function's entry block.
1052 if (MF->front().isBeginSection())
1053 MF->setSection(getObjFileLowering().getUniqueSectionForFunction(F, TM));
1054 else
1055 MF->setSection(getObjFileLowering().SectionForGlobal(GO: &F, TM));
1056 OutStreamer->switchSection(Section: MF->getSection());
1057
1058 if (MAI.isAIX())
1059 emitLinkage(GV: &F, GVSym: CurrentFnDescSym);
1060 else
1061 emitVisibility(Sym: CurrentFnSym, Visibility: F.getVisibility());
1062
1063 emitLinkage(GV: &F, GVSym: CurrentFnSym);
1064 if (MAI.hasFunctionAlignment()) {
1065 Align PrefAlign = MF->getPreferredAlignment();
1066 if (MAI.useIntegratedAssembler() && MAI.hasPreferredAlignment()) {
1067 // Emit .p2align for the effective minimum alignment (which accounts for
1068 // F's own align attribute via getGVAlignment), then emit .prefalign only
1069 // when the preferred alignment is greater. The end symbol must be
1070 // created here, before the function body, so that .prefalign can
1071 // reference it; emitFunctionBody will emit the label at the function
1072 // end.
1073 Align MinAlign = emitAlignment(Alignment: MF->getAlignment(), GV: &F);
1074 if (MinAlign < PrefAlign) {
1075 CurrentFnEnd = createTempSymbol(Name: "func_end");
1076 OutStreamer->emitPrefAlign(A: PrefAlign, End: *CurrentFnEnd,
1077 /*EmitNops=*/true, /*Fill=*/0,
1078 STI: getSubtargetInfo());
1079 }
1080 } else {
1081 emitAlignment(Alignment: PrefAlign, GV: &F);
1082 }
1083 }
1084
1085 if (MAI.hasDotTypeDotSizeDirective())
1086 OutStreamer->emitSymbolAttribute(Symbol: CurrentFnSym, Attribute: MCSA_ELF_TypeFunction);
1087
1088 if (F.hasFnAttribute(Kind: Attribute::Cold))
1089 OutStreamer->emitSymbolAttribute(Symbol: CurrentFnSym, Attribute: MCSA_Cold);
1090
1091 // Emit the prefix data.
1092 if (F.hasPrefixData())
1093 emitFunctionPrefix(Prefix: {F.getPrefixData()});
1094
1095 // Emit KCFI type information before patchable-function-prefix nops.
1096 emitKCFITypeId(MF: *MF);
1097
1098 // Emit M NOPs for -fpatchable-function-entry=N,M where M>0. We arbitrarily
1099 // place prefix data before NOPs.
1100 unsigned PatchableFunctionPrefix =
1101 F.getFnAttributeAsParsedInteger(Kind: "patchable-function-prefix");
1102 unsigned PatchableFunctionEntry =
1103 F.getFnAttributeAsParsedInteger(Kind: "patchable-function-entry");
1104 if (PatchableFunctionPrefix) {
1105 CurrentPatchableFunctionEntrySym =
1106 OutContext.createLinkerPrivateTempSymbol();
1107 OutStreamer->emitLabel(Symbol: CurrentPatchableFunctionEntrySym);
1108 emitNops(N: PatchableFunctionPrefix);
1109 } else if (PatchableFunctionEntry) {
1110 // May be reassigned when emitting the body, to reference the label after
1111 // the initial BTI (AArch64) or endbr32/endbr64 (x86).
1112 CurrentPatchableFunctionEntrySym = CurrentFnBegin;
1113 }
1114
1115 // Emit the function prologue data for the indirect call sanitizer.
1116 if (const MDNode *MD = F.getMetadata(KindID: LLVMContext::MD_func_sanitize)) {
1117 assert(MD->getNumOperands() == 2);
1118
1119 auto *PrologueSig = mdconst::extract<Constant>(MD: MD->getOperand(I: 0));
1120 auto *TypeHash = mdconst::extract<Constant>(MD: MD->getOperand(I: 1));
1121 emitFunctionPrefix(Prefix: {PrologueSig, TypeHash});
1122 }
1123
1124 if (isVerbose()) {
1125 F.printAsOperand(O&: OutStreamer->getCommentOS(),
1126 /*PrintType=*/false, M: F.getParent());
1127 emitFunctionHeaderComment();
1128 OutStreamer->getCommentOS() << '\n';
1129 }
1130
1131 // Emit the function descriptor. This is a virtual function to allow targets
1132 // to emit their specific function descriptor. Right now it is only used by
1133 // the AIX target. The PowerPC 64-bit V1 ELF target also uses function
1134 // descriptors and should be converted to use this hook as well.
1135 if (MAI.isAIX())
1136 emitFunctionDescriptor();
1137
1138 // Emit the CurrentFnSym. This is a virtual function to allow targets to do
1139 // their wild and crazy things as required.
1140 emitFunctionEntryLabel();
1141
1142 // If the function had address-taken blocks that got deleted, then we have
1143 // references to the dangling symbols. Emit them at the start of the function
1144 // so that we don't get references to undefined symbols.
1145 std::vector<MCSymbol*> DeadBlockSyms;
1146 takeDeletedSymbolsForFunction(F: &F, Result&: DeadBlockSyms);
1147 for (MCSymbol *DeadBlockSym : DeadBlockSyms) {
1148 OutStreamer->AddComment(T: "Address taken block that was later removed");
1149 OutStreamer->emitLabel(Symbol: DeadBlockSym);
1150 }
1151
1152 if (CurrentFnBegin) {
1153 if (MAI.useAssignmentForEHBegin()) {
1154 MCSymbol *CurPos = OutContext.createTempSymbol();
1155 OutStreamer->emitLabel(Symbol: CurPos);
1156 OutStreamer->emitAssignment(Symbol: CurrentFnBegin,
1157 Value: MCSymbolRefExpr::create(Symbol: CurPos, Ctx&: OutContext));
1158 } else {
1159 OutStreamer->emitLabel(Symbol: CurrentFnBegin);
1160 }
1161 }
1162
1163 // Emit pre-function debug and/or EH information.
1164 for (auto &Handler : Handlers) {
1165 Handler->beginFunction(MF);
1166 Handler->beginBasicBlockSection(MBB: MF->front());
1167 }
1168 for (auto &Handler : EHHandlers) {
1169 Handler->beginFunction(MF);
1170 Handler->beginBasicBlockSection(MBB: MF->front());
1171 }
1172
1173 // Emit the prologue data.
1174 if (F.hasPrologueData())
1175 emitGlobalConstant(DL: F.getDataLayout(), CV: F.getPrologueData());
1176}
1177
1178/// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
1179/// function. This can be overridden by targets as required to do custom stuff.
1180void AsmPrinter::emitFunctionEntryLabel() {
1181 CurrentFnSym->redefineIfPossible();
1182 OutStreamer->emitLabel(Symbol: CurrentFnSym);
1183
1184 if (TM.getTargetTriple().isOSBinFormatELF()) {
1185 MCSymbol *Sym = getSymbolPreferLocal(GV: MF->getFunction());
1186 if (Sym != CurrentFnSym) {
1187 CurrentFnBeginLocal = Sym;
1188 OutStreamer->emitLabel(Symbol: Sym);
1189 OutStreamer->emitSymbolAttribute(Symbol: Sym, Attribute: MCSA_ELF_TypeFunction);
1190 }
1191 }
1192}
1193
1194/// emitComments - Pretty-print comments for instructions.
1195static void emitComments(const MachineInstr &MI, const MCSubtargetInfo *STI,
1196 raw_ostream &CommentOS) {
1197 const MachineFunction *MF = MI.getMF();
1198 const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
1199
1200 // Check for spills and reloads
1201
1202 // We assume a single instruction only has a spill or reload, not
1203 // both.
1204 std::optional<LocationSize> Size;
1205 if ((Size = MI.getRestoreSize(TII))) {
1206 CommentOS << Size->getValue() << "-byte Reload\n";
1207 } else if ((Size = MI.getFoldedRestoreSize(TII))) {
1208 if (!Size->hasValue())
1209 CommentOS << "Unknown-size Folded Reload\n";
1210 else if (Size->getValue())
1211 CommentOS << Size->getValue() << "-byte Folded Reload\n";
1212 } else if ((Size = MI.getSpillSize(TII))) {
1213 CommentOS << Size->getValue() << "-byte Spill\n";
1214 } else if ((Size = MI.getFoldedSpillSize(TII))) {
1215 if (!Size->hasValue())
1216 CommentOS << "Unknown-size Folded Spill\n";
1217 else if (Size->getValue())
1218 CommentOS << Size->getValue() << "-byte Folded Spill\n";
1219 }
1220
1221 // Check for spill-induced copies
1222 if (MI.getAsmPrinterFlag(Flag: MachineInstr::ReloadReuse))
1223 CommentOS << " Reload Reuse\n";
1224
1225 if (PrintLatency) {
1226 const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
1227 const MCSchedModel &SCModel = STI->getSchedModel();
1228 int Latency = SCModel.computeInstrLatency<MCSubtargetInfo, MCInstrInfo,
1229 InstrItineraryData, MachineInstr>(
1230 STI: *STI, MCII: *TII, Inst: MI);
1231 // Report only interesting latencies.
1232 if (1 < Latency)
1233 CommentOS << " Latency: " << Latency << "\n";
1234 }
1235}
1236
1237/// emitImplicitDef - This method emits the specified machine instruction
1238/// that is an implicit def.
1239void AsmPrinter::emitImplicitDef(const MachineInstr *MI) const {
1240 Register RegNo = MI->getOperand(i: 0).getReg();
1241
1242 SmallString<128> Str;
1243 raw_svector_ostream OS(Str);
1244 OS << "implicit-def: "
1245 << printReg(Reg: RegNo, TRI: MF->getSubtarget().getRegisterInfo());
1246
1247 OutStreamer->AddComment(T: OS.str());
1248 OutStreamer->addBlankLine();
1249}
1250
1251static void emitKill(const MachineInstr *MI, AsmPrinter &AP) {
1252 std::string Str;
1253 raw_string_ostream OS(Str);
1254 OS << "kill:";
1255 for (const MachineOperand &Op : MI->operands()) {
1256 assert(Op.isReg() && "KILL instruction must have only register operands");
1257 OS << ' ' << (Op.isDef() ? "def " : "killed ")
1258 << printReg(Reg: Op.getReg(), TRI: AP.MF->getSubtarget().getRegisterInfo());
1259 }
1260 AP.OutStreamer->AddComment(T: Str);
1261 AP.OutStreamer->addBlankLine();
1262}
1263
1264static void emitFakeUse(const MachineInstr *MI, AsmPrinter &AP) {
1265 std::string Str;
1266 raw_string_ostream OS(Str);
1267 OS << "fake_use:";
1268 for (const MachineOperand &Op : MI->operands()) {
1269 // In some circumstances we can end up with fake uses of constants; skip
1270 // these.
1271 if (!Op.isReg())
1272 continue;
1273 OS << ' ' << printReg(Reg: Op.getReg(), TRI: AP.MF->getSubtarget().getRegisterInfo());
1274 }
1275 AP.OutStreamer->AddComment(T: OS.str());
1276 AP.OutStreamer->addBlankLine();
1277}
1278
1279/// emitDebugValueComment - This method handles the target-independent form
1280/// of DBG_VALUE, returning true if it was able to do so. A false return
1281/// means the target will need to handle MI in EmitInstruction.
1282static bool emitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
1283 // This code handles only the 4-operand target-independent form.
1284 if (MI->isNonListDebugValue() && MI->getNumOperands() != 4)
1285 return false;
1286
1287 SmallString<128> Str;
1288 raw_svector_ostream OS(Str);
1289 OS << "DEBUG_VALUE: ";
1290
1291 const DILocalVariable *V = MI->getDebugVariable();
1292 if (auto *SP = dyn_cast<DISubprogram>(Val: V->getScope())) {
1293 StringRef Name = SP->getName();
1294 if (!Name.empty())
1295 OS << Name << ":";
1296 }
1297 OS << V->getName();
1298 OS << " <- ";
1299
1300 const DIExpression *Expr = MI->getDebugExpression();
1301 // First convert this to a non-variadic expression if possible, to simplify
1302 // the output.
1303 if (auto NonVariadicExpr = DIExpression::convertToNonVariadicExpression(Expr))
1304 Expr = *NonVariadicExpr;
1305 // Then, output the possibly-simplified expression.
1306 if (Expr->getNumElements()) {
1307 OS << '[';
1308 ListSeparator LS;
1309 for (auto &Op : Expr->expr_ops()) {
1310 OS << LS << dwarf::OperationEncodingString(Encoding: Op.getOp());
1311 for (unsigned I = 0; I < Op.getNumArgs(); ++I)
1312 OS << ' ' << Op.getArg(I);
1313 }
1314 OS << "] ";
1315 }
1316
1317 // Register or immediate value. Register 0 means undef.
1318 for (const MachineOperand &Op : MI->debug_operands()) {
1319 if (&Op != MI->debug_operands().begin())
1320 OS << ", ";
1321 switch (Op.getType()) {
1322 case MachineOperand::MO_FPImmediate: {
1323 APFloat APF = APFloat(Op.getFPImm()->getValueAPF());
1324 Type *ImmTy = Op.getFPImm()->getType();
1325 if (ImmTy->isBFloatTy() || ImmTy->isHalfTy() || ImmTy->isFloatTy() ||
1326 ImmTy->isDoubleTy()) {
1327 OS << APF.convertToDouble();
1328 } else {
1329 // There is no good way to print long double. Convert a copy to
1330 // double. Ah well, it's only a comment.
1331 bool ignored;
1332 APF.convert(ToSemantics: APFloat::IEEEdouble(), RM: APFloat::rmNearestTiesToEven,
1333 losesInfo: &ignored);
1334 OS << "(long double) " << APF.convertToDouble();
1335 }
1336 break;
1337 }
1338 case MachineOperand::MO_Immediate: {
1339 OS << Op.getImm();
1340 break;
1341 }
1342 case MachineOperand::MO_CImmediate: {
1343 Op.getCImm()->getValue().print(OS, isSigned: false /*isSigned*/);
1344 break;
1345 }
1346 case MachineOperand::MO_TargetIndex: {
1347 OS << "!target-index(" << Op.getIndex() << "," << Op.getOffset() << ")";
1348 break;
1349 }
1350 case MachineOperand::MO_Register:
1351 case MachineOperand::MO_FrameIndex: {
1352 Register Reg;
1353 std::optional<StackOffset> Offset;
1354 if (Op.isReg()) {
1355 Reg = Op.getReg();
1356 } else {
1357 const TargetFrameLowering *TFI =
1358 AP.MF->getSubtarget().getFrameLowering();
1359 Offset = TFI->getFrameIndexReference(MF: *AP.MF, FI: Op.getIndex(), FrameReg&: Reg);
1360 }
1361 if (!Reg) {
1362 // Suppress offset, it is not meaningful here.
1363 OS << "undef";
1364 break;
1365 }
1366 // The second operand is only an offset if it's an immediate.
1367 if (MI->isIndirectDebugValue())
1368 Offset = StackOffset::getFixed(Fixed: MI->getDebugOffset().getImm());
1369 if (Offset)
1370 OS << '[';
1371 OS << printReg(Reg, TRI: AP.MF->getSubtarget().getRegisterInfo());
1372 if (Offset)
1373 OS << '+' << Offset->getFixed() << ']';
1374 break;
1375 }
1376 default:
1377 llvm_unreachable("Unknown operand type");
1378 }
1379 }
1380
1381 // NOTE: Want this comment at start of line, don't emit with AddComment.
1382 AP.OutStreamer->emitRawComment(T: Str);
1383 return true;
1384}
1385
1386/// This method handles the target-independent form of DBG_LABEL, returning
1387/// true if it was able to do so. A false return means the target will need
1388/// to handle MI in EmitInstruction.
1389static bool emitDebugLabelComment(const MachineInstr *MI, AsmPrinter &AP) {
1390 if (MI->getNumOperands() != 1)
1391 return false;
1392
1393 SmallString<128> Str;
1394 raw_svector_ostream OS(Str);
1395 OS << "DEBUG_LABEL: ";
1396
1397 const DILabel *V = MI->getDebugLabel();
1398 if (auto *SP = dyn_cast<DISubprogram>(
1399 Val: V->getScope()->getNonLexicalBlockFileScope())) {
1400 StringRef Name = SP->getName();
1401 if (!Name.empty())
1402 OS << Name << ":";
1403 }
1404 OS << V->getName();
1405
1406 // NOTE: Want this comment at start of line, don't emit with AddComment.
1407 AP.OutStreamer->emitRawComment(T: OS.str());
1408 return true;
1409}
1410
1411AsmPrinter::CFISection
1412AsmPrinter::getFunctionCFISectionType(const Function &F) const {
1413 // Ignore functions that won't get emitted.
1414 if (F.isDeclarationForLinker())
1415 return CFISection::None;
1416
1417 if (MAI.getExceptionHandlingType() == ExceptionHandling::DwarfCFI &&
1418 F.needsUnwindTableEntry())
1419 return CFISection::EH;
1420
1421 if (MAI.usesCFIWithoutEH() && F.hasUWTable())
1422 return CFISection::EH;
1423
1424 if (hasDebugInfo() || TM.Options.ForceDwarfFrameSection)
1425 return CFISection::Debug;
1426
1427 return CFISection::None;
1428}
1429
1430AsmPrinter::CFISection
1431AsmPrinter::getFunctionCFISectionType(const MachineFunction &MF) const {
1432 return getFunctionCFISectionType(F: MF.getFunction());
1433}
1434
1435bool AsmPrinter::needsSEHMoves() {
1436 return MAI.usesWindowsCFI() && MF->getFunction().needsUnwindTableEntry();
1437}
1438
1439bool AsmPrinter::usesCFIWithoutEH() const {
1440 return MAI.usesCFIWithoutEH() && ModuleCFISection != CFISection::None;
1441}
1442
1443void AsmPrinter::emitCFIInstruction(const MachineInstr &MI) {
1444 ExceptionHandling ExceptionHandlingType = MAI.getExceptionHandlingType();
1445 if (!usesCFIWithoutEH() &&
1446 ExceptionHandlingType != ExceptionHandling::DwarfCFI &&
1447 ExceptionHandlingType != ExceptionHandling::ARM)
1448 return;
1449
1450 if (getFunctionCFISectionType(MF: *MF) == CFISection::None)
1451 return;
1452
1453 // If there is no "real" instruction following this CFI instruction, skip
1454 // emitting it; it would be beyond the end of the function's FDE range.
1455 auto *MBB = MI.getParent();
1456 auto I = std::next(x: MI.getIterator());
1457 while (I != MBB->end() && I->isTransient())
1458 ++I;
1459 if (I == MBB->instr_end() &&
1460 MBB->getReverseIterator() == MBB->getParent()->rbegin())
1461 return;
1462
1463 const std::vector<MCCFIInstruction> &Instrs = MF->getFrameInstructions();
1464 unsigned CFIIndex = MI.getOperand(i: 0).getCFIIndex();
1465 const MCCFIInstruction &CFI = Instrs[CFIIndex];
1466 emitCFIInstruction(Inst: CFI);
1467}
1468
1469void AsmPrinter::emitFrameAlloc(const MachineInstr &MI) {
1470 // The operands are the MCSymbol and the frame offset of the allocation.
1471 MCSymbol *FrameAllocSym = MI.getOperand(i: 0).getMCSymbol();
1472 int FrameOffset = MI.getOperand(i: 1).getImm();
1473
1474 // Emit a symbol assignment.
1475 OutStreamer->emitAssignment(Symbol: FrameAllocSym,
1476 Value: MCConstantExpr::create(Value: FrameOffset, Ctx&: OutContext));
1477}
1478
1479/// Returns the BB metadata to be emitted in the SHT_LLVM_BB_ADDR_MAP section
1480/// for a given basic block. This can be used to capture more precise profile
1481/// information.
1482static uint32_t getBBAddrMapMetadata(const MachineBasicBlock &MBB) {
1483 const TargetInstrInfo *TII = MBB.getParent()->getSubtarget().getInstrInfo();
1484 return object::BBAddrMap::BBEntry::Metadata{
1485 .HasReturn: MBB.isReturnBlock(), .HasTailCall: !MBB.empty() && TII->isTailCall(Inst: MBB.back()),
1486 .IsEHPad: MBB.isEHPad(), .CanFallThrough: const_cast<MachineBasicBlock &>(MBB).canFallThrough(),
1487 .HasIndirectBranch: !MBB.empty() && MBB.rbegin()->isIndirectBranch()}
1488 .encode();
1489}
1490
1491static llvm::object::BBAddrMap::Features
1492getBBAddrMapFeature(const MachineFunction &MF, int NumMBBSectionRanges,
1493 bool HasCalls, const CFGProfile *FuncCFGProfile) {
1494 // Ensure that the user has not passed in additional options while also
1495 // specifying all or none.
1496 if ((PgoAnalysisMapFeatures.isSet(V: PGOMapFeaturesEnum::None) ||
1497 PgoAnalysisMapFeatures.isSet(V: PGOMapFeaturesEnum::All)) &&
1498 popcount(Value: PgoAnalysisMapFeatures.getBits()) != 1) {
1499 MF.getFunction().getContext().emitError(
1500 ErrorStr: "-pgo-analysis-map can accept only all or none with no additional "
1501 "values.");
1502 }
1503
1504 bool NoFeatures = PgoAnalysisMapFeatures.isSet(V: PGOMapFeaturesEnum::None);
1505 bool AllFeatures = PgoAnalysisMapFeatures.isSet(V: PGOMapFeaturesEnum::All);
1506 bool FuncEntryCountEnabled =
1507 AllFeatures || (!NoFeatures && PgoAnalysisMapFeatures.isSet(
1508 V: PGOMapFeaturesEnum::FuncEntryCount));
1509 bool BBFreqEnabled =
1510 AllFeatures ||
1511 (!NoFeatures && PgoAnalysisMapFeatures.isSet(V: PGOMapFeaturesEnum::BBFreq));
1512 bool BrProbEnabled =
1513 AllFeatures ||
1514 (!NoFeatures && PgoAnalysisMapFeatures.isSet(V: PGOMapFeaturesEnum::BrProb));
1515 bool PostLinkCfgEnabled = FuncCFGProfile && PgoAnalysisMapEmitBBSectionsCfg;
1516
1517 if ((BBFreqEnabled || BrProbEnabled) && BBAddrMapSkipEmitBBEntries) {
1518 MF.getFunction().getContext().emitError(
1519 ErrorStr: "BB entries info is required for BBFreq and BrProb features");
1520 }
1521 return {.FuncEntryCount: FuncEntryCountEnabled, .BBFreq: BBFreqEnabled, .BrProb: BrProbEnabled,
1522 .MultiBBRange: MF.hasBBSections() && NumMBBSectionRanges > 1,
1523 // Use static_cast to avoid breakage of tests on windows.
1524 .OmitBBEntries: static_cast<bool>(BBAddrMapSkipEmitBBEntries), .CallsiteEndOffsets: HasCalls,
1525 .BBHash: static_cast<bool>(EmitBBHash), .PostLinkCfg: PostLinkCfgEnabled};
1526}
1527
1528void AsmPrinter::emitBBAddrMapSection(const MachineFunction &MF) {
1529 MCSection *BBAddrMapSection =
1530 getObjFileLowering().getBBAddrMapSection(TextSec: *MF.getSection());
1531 assert(BBAddrMapSection && ".llvm_bb_addr_map section is not initialized.");
1532 bool HasCalls = !CurrentFnCallsiteEndSymbols.empty();
1533
1534 const BasicBlockSectionsProfileReader *BBSPR = nullptr;
1535 if (auto *BBSPRPass =
1536 getAnalysisIfAvailable<BasicBlockSectionsProfileReaderWrapperPass>())
1537 BBSPR = &BBSPRPass->getBBSPR();
1538 const CFGProfile *FuncCFGProfile = nullptr;
1539 if (BBSPR)
1540 FuncCFGProfile = BBSPR->getFunctionCFGProfile(FuncName: MF.getFunction().getName());
1541
1542 const MCSymbol *FunctionSymbol = getFunctionBegin();
1543
1544 OutStreamer->pushSection();
1545 OutStreamer->switchSection(Section: BBAddrMapSection);
1546 OutStreamer->AddComment(T: "version");
1547 uint8_t BBAddrMapVersion = OutStreamer->getContext().getBBAddrMapVersion();
1548 OutStreamer->emitInt8(Value: BBAddrMapVersion);
1549 OutStreamer->AddComment(T: "feature");
1550 auto Features = getBBAddrMapFeature(MF, NumMBBSectionRanges: MBBSectionRanges.size(), HasCalls,
1551 FuncCFGProfile);
1552 OutStreamer->emitInt16(Value: Features.encode());
1553 // Emit BB Information for each basic block in the function.
1554 if (Features.MultiBBRange) {
1555 OutStreamer->AddComment(T: "number of basic block ranges");
1556 OutStreamer->emitULEB128IntValue(Value: MBBSectionRanges.size());
1557 }
1558 // Number of blocks in each MBB section.
1559 DenseMap<MBBSectionID, unsigned> MBBSectionNumBlocks;
1560 const MCSymbol *PrevMBBEndSymbol = nullptr;
1561 if (!Features.MultiBBRange) {
1562 OutStreamer->AddComment(T: "function address");
1563 OutStreamer->emitSymbolValue(Sym: FunctionSymbol, Size: getPointerSize());
1564 OutStreamer->AddComment(T: "number of basic blocks");
1565 OutStreamer->emitULEB128IntValue(Value: MF.size());
1566 PrevMBBEndSymbol = FunctionSymbol;
1567 } else {
1568 unsigned BBCount = 0;
1569 for (const MachineBasicBlock &MBB : MF) {
1570 BBCount++;
1571 if (MBB.isEndSection()) {
1572 // Store each section's basic block count when it ends.
1573 MBBSectionNumBlocks[MBB.getSectionID()] = BBCount;
1574 // Reset the count for the next section.
1575 BBCount = 0;
1576 }
1577 }
1578 }
1579 // Emit the BB entry for each basic block in the function.
1580 for (const MachineBasicBlock &MBB : MF) {
1581 const MCSymbol *MBBSymbol =
1582 MBB.isEntryBlock() ? FunctionSymbol : MBB.getSymbol();
1583 bool IsBeginSection =
1584 Features.MultiBBRange && (MBB.isBeginSection() || MBB.isEntryBlock());
1585 if (IsBeginSection) {
1586 OutStreamer->AddComment(T: "base address");
1587 OutStreamer->emitSymbolValue(Sym: MBBSymbol, Size: getPointerSize());
1588 OutStreamer->AddComment(T: "number of basic blocks");
1589 OutStreamer->emitULEB128IntValue(Value: MBBSectionNumBlocks[MBB.getSectionID()]);
1590 PrevMBBEndSymbol = MBBSymbol;
1591 }
1592
1593 auto MBHI =
1594 Features.BBHash ? &getAnalysis<MachineBlockHashInfo>() : nullptr;
1595
1596 if (!Features.OmitBBEntries) {
1597 OutStreamer->AddComment(T: "BB id");
1598 // Emit the BB ID for this basic block.
1599 // We only emit BaseID since CloneID is unset for
1600 // -basic-block-adress-map.
1601 // TODO: Emit the full BBID when labels and sections can be mixed
1602 // together.
1603 OutStreamer->emitULEB128IntValue(Value: MBB.getBBID()->BaseID);
1604 // Emit the basic block offset relative to the end of the previous block.
1605 // This is zero unless the block is padded due to alignment.
1606 emitLabelDifferenceAsULEB128(Hi: MBBSymbol, Lo: PrevMBBEndSymbol);
1607 const MCSymbol *CurrentLabel = MBBSymbol;
1608 if (HasCalls) {
1609 auto CallsiteEndSymbols = CurrentFnCallsiteEndSymbols.lookup(Val: &MBB);
1610 OutStreamer->AddComment(T: "number of callsites");
1611 OutStreamer->emitULEB128IntValue(Value: CallsiteEndSymbols.size());
1612 for (const MCSymbol *CallsiteEndSymbol : CallsiteEndSymbols) {
1613 // Emit the callsite offset.
1614 emitLabelDifferenceAsULEB128(Hi: CallsiteEndSymbol, Lo: CurrentLabel);
1615 CurrentLabel = CallsiteEndSymbol;
1616 }
1617 }
1618 // Emit the offset to the end of the block, which can be used to compute
1619 // the total block size.
1620 emitLabelDifferenceAsULEB128(Hi: MBB.getEndSymbol(), Lo: CurrentLabel);
1621 // Emit the Metadata.
1622 OutStreamer->emitULEB128IntValue(Value: getBBAddrMapMetadata(MBB));
1623 // Emit the Hash.
1624 if (MBHI) {
1625 OutStreamer->emitInt64(Value: MBHI->getMBBHash(MBB));
1626 }
1627 }
1628 PrevMBBEndSymbol = MBB.getEndSymbol();
1629 }
1630
1631 if (Features.hasPGOAnalysis()) {
1632 assert(BBAddrMapVersion >= 2 &&
1633 "PGOAnalysisMap only supports version 2 or later");
1634
1635 if (Features.FuncEntryCount) {
1636 OutStreamer->AddComment(T: "function entry count");
1637 auto MaybeEntryCount = MF.getFunction().getEntryCount();
1638 OutStreamer->emitULEB128IntValue(Value: MaybeEntryCount ? *MaybeEntryCount : 0);
1639 }
1640 const MachineBlockFrequencyInfo *MBFI =
1641 Features.BBFreq
1642 ? &getAnalysis<LazyMachineBlockFrequencyInfoPass>().getBFI()
1643 : nullptr;
1644 const MachineBranchProbabilityInfo *MBPI =
1645 Features.BrProb
1646 ? &getAnalysis<MachineBranchProbabilityInfoWrapperPass>().getMBPI()
1647 : nullptr;
1648
1649 if (Features.BBFreq || Features.BrProb) {
1650 for (const MachineBasicBlock &MBB : MF) {
1651 if (Features.BBFreq) {
1652 OutStreamer->AddComment(T: "basic block frequency");
1653 OutStreamer->emitULEB128IntValue(
1654 Value: MBFI->getBlockFreq(MBB: &MBB).getFrequency());
1655 if (Features.PostLinkCfg) {
1656 OutStreamer->AddComment(T: "basic block frequency (propeller)");
1657 OutStreamer->emitULEB128IntValue(
1658 Value: FuncCFGProfile->getBlockCount(BBID: *MBB.getBBID()));
1659 }
1660 }
1661 if (Features.BrProb) {
1662 unsigned SuccCount = MBB.succ_size();
1663 OutStreamer->AddComment(T: "basic block successor count");
1664 OutStreamer->emitULEB128IntValue(Value: SuccCount);
1665 for (const MachineBasicBlock *SuccMBB : MBB.successors()) {
1666 OutStreamer->AddComment(T: "successor BB ID");
1667 OutStreamer->emitULEB128IntValue(Value: SuccMBB->getBBID()->BaseID);
1668 OutStreamer->AddComment(T: "successor branch probability");
1669 OutStreamer->emitULEB128IntValue(
1670 Value: MBPI->getEdgeProbability(Src: &MBB, Dst: SuccMBB).getNumerator());
1671 if (Features.PostLinkCfg) {
1672 OutStreamer->AddComment(T: "successor branch frequency (propeller)");
1673 OutStreamer->emitULEB128IntValue(Value: FuncCFGProfile->getEdgeCount(
1674 SrcBBID: *MBB.getBBID(), SinkBBID: *SuccMBB->getBBID()));
1675 }
1676 }
1677 }
1678 }
1679 }
1680 }
1681
1682 OutStreamer->popSection();
1683}
1684
1685void AsmPrinter::emitKCFITrapEntry(const MachineFunction &MF,
1686 const MCSymbol *Symbol) {
1687 MCSection *Section =
1688 getObjFileLowering().getKCFITrapSection(TextSec: *MF.getSection());
1689 if (!Section)
1690 return;
1691
1692 OutStreamer->pushSection();
1693 OutStreamer->switchSection(Section);
1694
1695 MCSymbol *Loc = OutContext.createLinkerPrivateTempSymbol();
1696 OutStreamer->emitLabel(Symbol: Loc);
1697 OutStreamer->emitAbsoluteSymbolDiff(Hi: Symbol, Lo: Loc, Size: 4);
1698
1699 OutStreamer->popSection();
1700}
1701
1702void AsmPrinter::emitKCFITypeId(const MachineFunction &MF) {
1703 const Function &F = MF.getFunction();
1704 if (const MDNode *MD = F.getMetadata(KindID: LLVMContext::MD_kcfi_type))
1705 emitGlobalConstant(DL: F.getDataLayout(),
1706 CV: mdconst::extract<ConstantInt>(MD: MD->getOperand(I: 0)));
1707}
1708
1709void AsmPrinter::emitPseudoProbe(const MachineInstr &MI) {
1710 if (PP) {
1711 auto GUID = MI.getOperand(i: 0).getImm();
1712 auto Index = MI.getOperand(i: 1).getImm();
1713 auto Type = MI.getOperand(i: 2).getImm();
1714 auto Attr = MI.getOperand(i: 3).getImm();
1715 DILocation *DebugLoc = MI.getDebugLoc();
1716 PP->emitPseudoProbe(Guid: GUID, Index, Type, Attr, DebugLoc);
1717 }
1718}
1719
1720void AsmPrinter::emitStackSizeSection(const MachineFunction &MF) {
1721 if (!MF.getTarget().Options.EmitStackSizeSection)
1722 return;
1723
1724 MCSection *StackSizeSection =
1725 getObjFileLowering().getStackSizesSection(TextSec: *MF.getSection());
1726 if (!StackSizeSection)
1727 return;
1728
1729 const MachineFrameInfo &FrameInfo = MF.getFrameInfo();
1730 // Don't emit functions with dynamic stack allocations.
1731 if (FrameInfo.hasVarSizedObjects())
1732 return;
1733
1734 OutStreamer->pushSection();
1735 OutStreamer->switchSection(Section: StackSizeSection);
1736
1737 const MCSymbol *FunctionSymbol = getFunctionBegin();
1738 uint64_t StackSize =
1739 FrameInfo.getStackSize() + FrameInfo.getUnsafeStackSize();
1740 OutStreamer->emitSymbolValue(Sym: FunctionSymbol, Size: TM.getProgramPointerSize());
1741 OutStreamer->emitULEB128IntValue(Value: StackSize);
1742
1743 OutStreamer->popSection();
1744}
1745
1746void AsmPrinter::emitStackUsage(const MachineFunction &MF) {
1747 const std::string OutputFilename =
1748 !StackUsageFile.empty() ? StackUsageFile
1749 : MF.getTarget().Options.StackUsageFile;
1750
1751 // OutputFilename empty implies -fstack-usage is not passed.
1752 if (OutputFilename.empty())
1753 return;
1754
1755 const MachineFrameInfo &FrameInfo = MF.getFrameInfo();
1756 uint64_t StackSize =
1757 FrameInfo.getStackSize() + FrameInfo.getUnsafeStackSize();
1758
1759 if (StackUsageStream == nullptr) {
1760 std::error_code EC;
1761 StackUsageStream =
1762 std::make_unique<raw_fd_ostream>(args: OutputFilename, args&: EC, args: sys::fs::OF_Text);
1763 if (EC) {
1764 errs() << "Could not open file: " << EC.message();
1765 return;
1766 }
1767 }
1768
1769 if (const DISubprogram *DSP = MF.getFunction().getSubprogram())
1770 *StackUsageStream << DSP->getFilename() << ':' << DSP->getLine();
1771 else
1772 *StackUsageStream << MF.getFunction().getParent()->getName();
1773
1774 *StackUsageStream << ':' << MF.getName() << '\t' << StackSize << '\t';
1775 if (FrameInfo.hasVarSizedObjects())
1776 *StackUsageStream << "dynamic\n";
1777 else
1778 *StackUsageStream << "static\n";
1779}
1780
1781/// Extracts a numeric type identifier of a Function's type from
1782/// callgraph metadata. Returns null if metadata cannot be found.
1783static ConstantInt *extractNumericCGTypeId(const Function &F) {
1784 SmallVector<MDNode *, 2> Types;
1785 F.getMetadata(KindID: LLVMContext::MD_callgraph, MDs&: Types);
1786 for (const auto &Type : Types) {
1787 if (Type->getNumOperands() == 1 && isa<MDString>(Val: Type->getOperand(I: 0))) {
1788 MDString *MDTypeId = cast<MDString>(Val: Type->getOperand(I: 0));
1789 uint64_t TypeIdVal = llvm::MD5Hash(Str: MDTypeId->getString());
1790 IntegerType *Int64Ty = Type::getInt64Ty(C&: F.getContext());
1791 return ConstantInt::get(Ty: Int64Ty, V: TypeIdVal);
1792 }
1793 }
1794 return nullptr;
1795}
1796
1797/// Emits .llvm.callgraph section.
1798void AsmPrinter::emitCallGraphSection(const MachineFunction &MF,
1799 FunctionCallGraphInfo &FuncCGInfo) {
1800 if (!MF.getTarget().Options.EmitCallGraphSection)
1801 return;
1802
1803 // Switch to the call graph section for the function
1804 MCSection *FuncCGSection =
1805 getObjFileLowering().getCallGraphSection(TextSec: *getCurrentSection());
1806 assert(FuncCGSection && "null callgraph section");
1807 OutStreamer->pushSection();
1808 OutStreamer->switchSection(Section: FuncCGSection);
1809
1810 const Function &F = MF.getFunction();
1811 // If this function has external linkage or has its address taken and
1812 // it is not a callback, then anything could call it.
1813 bool IsIndirectTarget =
1814 !F.hasLocalLinkage() || F.hasAddressTaken(nullptr,
1815 /*IgnoreCallbackUses=*/true,
1816 /*IgnoreAssumeLikeCalls=*/true,
1817 /*IgnoreLLVMUsed=*/IngoreLLVMUsed: false);
1818
1819 const auto &DirectCallees = FuncCGInfo.DirectCallees;
1820 const auto &IndirectCalleeTypeIDs = FuncCGInfo.IndirectCalleeTypeIDs;
1821
1822 using namespace callgraph;
1823 Flags CGFlags = Flags::None;
1824 if (IsIndirectTarget)
1825 CGFlags |= Flags::IsIndirectTarget;
1826 if (DirectCallees.size() > 0)
1827 CGFlags |= Flags::HasDirectCallees;
1828 if (IndirectCalleeTypeIDs.size() > 0)
1829 CGFlags |= Flags::HasIndirectCallees;
1830
1831 // Emit function's call graph information.
1832 // 1) CallGraphSectionFormatVersion
1833 // 2) Flags
1834 // a. LSB bit 0 is set to 1 if the function is a potential indirect
1835 // target.
1836 // b. LSB bit 1 is set to 1 if there are direct callees.
1837 // c. LSB bit 2 is set to 1 if there are indirect callees.
1838 // d. Rest of the 5 bits in Flags are reserved for any future use.
1839 // 3) Function entry PC.
1840 // 4) FunctionTypeID if the function is indirect target and its type id
1841 // is known, otherwise it is set to 0.
1842 // 5) Number of unique direct callees, if at least one exists.
1843 // 6) For each unique direct callee, the callee's PC.
1844 // 7) Number of unique indirect target type IDs, if at least one exists.
1845 // 8) Each unique indirect target type id.
1846 OutStreamer->emitInt8(Value: CallGraphSectionFormatVersion::V_0);
1847 OutStreamer->emitInt8(Value: static_cast<uint8_t>(CGFlags));
1848 OutStreamer->emitSymbolValue(Sym: getSymbol(GV: &F), Size: TM.getProgramPointerSize());
1849 const auto *TypeId = extractNumericCGTypeId(F);
1850 if (IsIndirectTarget && TypeId)
1851 OutStreamer->emitInt64(Value: TypeId->getZExtValue());
1852 else
1853 OutStreamer->emitInt64(Value: 0);
1854
1855 if (DirectCallees.size() > 0) {
1856 OutStreamer->emitULEB128IntValue(Value: DirectCallees.size());
1857 for (const auto &CalleeSymbol : DirectCallees)
1858 OutStreamer->emitSymbolValue(Sym: CalleeSymbol, Size: TM.getProgramPointerSize());
1859 FuncCGInfo.DirectCallees.clear();
1860 }
1861 if (IndirectCalleeTypeIDs.size() > 0) {
1862 OutStreamer->emitULEB128IntValue(Value: IndirectCalleeTypeIDs.size());
1863 for (const auto &CalleeTypeId : IndirectCalleeTypeIDs)
1864 OutStreamer->emitInt64(Value: CalleeTypeId);
1865 FuncCGInfo.IndirectCalleeTypeIDs.clear();
1866 }
1867 // End of emitting call graph section contents.
1868 OutStreamer->popSection();
1869}
1870
1871void AsmPrinter::emitPCSectionsLabel(const MachineFunction &MF,
1872 const MDNode &MD) {
1873 MCSymbol *S = MF.getContext().createTempSymbol(Name: "pcsection");
1874 OutStreamer->emitLabel(Symbol: S);
1875 PCSectionsSymbols[&MD].emplace_back(Args&: S);
1876}
1877
1878void AsmPrinter::emitPCSections(const MachineFunction &MF) {
1879 const Function &F = MF.getFunction();
1880 if (PCSectionsSymbols.empty() && !F.hasMetadata(KindID: LLVMContext::MD_pcsections))
1881 return;
1882
1883 const CodeModel::Model CM = MF.getTarget().getCodeModel();
1884 const unsigned RelativeRelocSize =
1885 (CM == CodeModel::Medium || CM == CodeModel::Large) ? getPointerSize()
1886 : 4;
1887
1888 // Switch to PCSection, short-circuiting the common case where the current
1889 // section is still valid (assume most MD_pcsections contain just 1 section).
1890 auto SwitchSection = [&, Prev = StringRef()](const StringRef &Sec) mutable {
1891 if (Sec == Prev)
1892 return;
1893 MCSection *S = getObjFileLowering().getPCSection(Name: Sec, TextSec: MF.getSection());
1894 assert(S && "PC section is not initialized");
1895 OutStreamer->switchSection(Section: S);
1896 Prev = Sec;
1897 };
1898 // Emit symbols into sections and data as specified in the pcsections MDNode.
1899 auto EmitForMD = [&](const MDNode &MD, ArrayRef<const MCSymbol *> Syms,
1900 bool Deltas) {
1901 // Expect the first operand to be a section name. After that, a tuple of
1902 // constants may appear, which will simply be emitted into the current
1903 // section (the user of MD_pcsections decides the format of encoded data).
1904 assert(isa<MDString>(MD.getOperand(0)) && "first operand not a string");
1905 bool ConstULEB128 = false;
1906 for (const MDOperand &MDO : MD.operands()) {
1907 if (auto *S = dyn_cast<MDString>(Val: MDO)) {
1908 // Found string, start of new section!
1909 // Find options for this section "<section>!<opts>" - supported options:
1910 // C = Compress constant integers of size 2-8 bytes as ULEB128.
1911 const StringRef SecWithOpt = S->getString();
1912 const size_t OptStart = SecWithOpt.find(C: '!'); // likely npos
1913 const StringRef Sec = SecWithOpt.substr(Start: 0, N: OptStart);
1914 const StringRef Opts = SecWithOpt.substr(Start: OptStart); // likely empty
1915 ConstULEB128 = Opts.contains(C: 'C');
1916#ifndef NDEBUG
1917 for (char O : Opts)
1918 assert((O == '!' || O == 'C') && "Invalid !pcsections options");
1919#endif
1920 SwitchSection(Sec);
1921 const MCSymbol *Prev = Syms.front();
1922 for (const MCSymbol *Sym : Syms) {
1923 if (Sym == Prev || !Deltas) {
1924 // Use the entry itself as the base of the relative offset.
1925 MCSymbol *Base = MF.getContext().createTempSymbol(Name: "pcsection_base");
1926 OutStreamer->emitLabel(Symbol: Base);
1927 // Emit relative relocation `addr - base`, which avoids a dynamic
1928 // relocation in the final binary. User will get the address with
1929 // `base + addr`.
1930 emitLabelDifference(Hi: Sym, Lo: Base, Size: RelativeRelocSize);
1931 } else {
1932 // Emit delta between symbol and previous symbol.
1933 if (ConstULEB128)
1934 emitLabelDifferenceAsULEB128(Hi: Sym, Lo: Prev);
1935 else
1936 emitLabelDifference(Hi: Sym, Lo: Prev, Size: 4);
1937 }
1938 Prev = Sym;
1939 }
1940 } else {
1941 // Emit auxiliary data after PC.
1942 assert(isa<MDNode>(MDO) && "expecting either string or tuple");
1943 const auto *AuxMDs = cast<MDNode>(Val: MDO);
1944 for (const MDOperand &AuxMDO : AuxMDs->operands()) {
1945 assert(isa<ConstantAsMetadata>(AuxMDO) && "expecting a constant");
1946 const Constant *C = cast<ConstantAsMetadata>(Val: AuxMDO)->getValue();
1947 const DataLayout &DL = F.getDataLayout();
1948 const uint64_t Size = DL.getTypeStoreSize(Ty: C->getType());
1949
1950 if (auto *CI = dyn_cast<ConstantInt>(Val: C);
1951 CI && ConstULEB128 && Size > 1 && Size <= 8) {
1952 emitULEB128(Value: CI->getZExtValue());
1953 } else {
1954 emitGlobalConstant(DL, CV: C);
1955 }
1956 }
1957 }
1958 }
1959 };
1960
1961 OutStreamer->pushSection();
1962 // Emit PCs for function start and function size.
1963 if (const MDNode *MD = F.getMetadata(KindID: LLVMContext::MD_pcsections))
1964 EmitForMD(*MD, {getFunctionBegin(), getFunctionEnd()}, true);
1965 // Emit PCs for instructions collected.
1966 for (const auto &MS : PCSectionsSymbols)
1967 EmitForMD(*MS.first, MS.second, false);
1968 OutStreamer->popSection();
1969 PCSectionsSymbols.clear();
1970}
1971
1972/// Returns true if function begin and end labels should be emitted.
1973static bool needFuncLabels(const MachineFunction &MF, const AsmPrinter &Asm) {
1974 if (Asm.hasDebugInfo() || !MF.getLandingPads().empty() ||
1975 MF.hasEHFunclets() ||
1976 MF.getFunction().hasMetadata(KindID: LLVMContext::MD_pcsections))
1977 return true;
1978
1979 // We might emit an EH table that uses function begin and end labels even if
1980 // we don't have any landingpads.
1981 if (!MF.getFunction().hasPersonalityFn())
1982 return false;
1983 return !isNoOpWithoutInvoke(
1984 Pers: classifyEHPersonality(Pers: MF.getFunction().getPersonalityFn()));
1985}
1986
1987// Return the mnemonic of a MachineInstr if available, or the MachineInstr
1988// opcode name otherwise.
1989static StringRef getMIMnemonic(const MachineInstr &MI, MCStreamer &Streamer) {
1990 const TargetInstrInfo *TII =
1991 MI.getParent()->getParent()->getSubtarget().getInstrInfo();
1992 MCInst MCI;
1993 MCI.setOpcode(MI.getOpcode());
1994 if (StringRef Name = Streamer.getMnemonic(MI: MCI); !Name.empty())
1995 return Name;
1996 StringRef Name = TII->getName(Opcode: MI.getOpcode());
1997 assert(!Name.empty() && "Missing mnemonic and name for opcode");
1998 return Name;
1999}
2000
2001void AsmPrinter::handleCallsiteForCallgraph(
2002 FunctionCallGraphInfo &FuncCGInfo,
2003 const MachineFunction::CallSiteInfoMap &CallSitesInfoMap,
2004 const MachineInstr &MI) {
2005 assert(MI.isCall() && "This method is meant for call instructions only.");
2006 const MachineOperand &CalleeOperand = MI.getOperand(i: 0);
2007 if (CalleeOperand.isGlobal() || CalleeOperand.isSymbol()) {
2008 // Handle direct calls.
2009 MCSymbol *CalleeSymbol = nullptr;
2010 switch (CalleeOperand.getType()) {
2011 case llvm::MachineOperand::MO_GlobalAddress:
2012 CalleeSymbol = getSymbol(GV: CalleeOperand.getGlobal());
2013 break;
2014 case llvm::MachineOperand::MO_ExternalSymbol:
2015 CalleeSymbol = GetExternalSymbolSymbol(Sym: CalleeOperand.getSymbolName());
2016 break;
2017 default:
2018 llvm_unreachable(
2019 "Expected to only handle direct call instructions here.");
2020 }
2021 FuncCGInfo.DirectCallees.insert(X: CalleeSymbol);
2022 return; // Early exit after handling the direct call instruction.
2023 }
2024 const auto &CallSiteInfo = CallSitesInfoMap.find(Val: &MI);
2025 if (CallSiteInfo == CallSitesInfoMap.end())
2026 return;
2027 // Handle indirect callsite info.
2028 // Only indirect calls have type identifiers set.
2029 for (ConstantInt *CalleeTypeId : CallSiteInfo->second.CalleeTypeIds) {
2030 uint64_t CalleeTypeIdVal = CalleeTypeId->getZExtValue();
2031 FuncCGInfo.IndirectCalleeTypeIDs.insert(X: CalleeTypeIdVal);
2032 }
2033}
2034
2035/// Helper to emit a symbol for the prefetch target associated with the given
2036/// BBID and callsite index.
2037void AsmPrinter::emitPrefetchTargetSymbol(const UniqueBBID &BBID,
2038 unsigned CallsiteIndex) {
2039 SmallString<128> FunctionName;
2040 getNameWithPrefix(Name&: FunctionName, GV: &MF->getFunction());
2041 MCSymbol *PrefetchTargetSymbol = OutContext.getOrCreateSymbol(
2042 Name: getPrefetchTargetSymbolName(FunctionName, BBID, CallsiteIndex));
2043 // If the function is weak-linkage it may be replaced by a strong
2044 // version, in which case the prefetch targets should also be replaced.
2045 OutStreamer->emitSymbolAttribute(
2046 Symbol: PrefetchTargetSymbol,
2047 Attribute: MF->getFunction().isWeakForLinker() ? MCSA_Weak : MCSA_Global);
2048 OutStreamer->emitLabel(Symbol: PrefetchTargetSymbol);
2049}
2050
2051/// Emit dangling prefetch targets that were not mapped to any basic block.
2052void AsmPrinter::emitDanglingPrefetchTargets() {
2053 const DenseMap<UniqueBBID, SmallVector<unsigned>> &MFPrefetchTargets =
2054 MF->getPrefetchTargets();
2055 if (MFPrefetchTargets.empty())
2056 return;
2057 DenseSet<UniqueBBID> MFBBIDs;
2058 for (const MachineBasicBlock &MBB : *MF)
2059 if (std::optional<UniqueBBID> BBID = MBB.getBBID())
2060 MFBBIDs.insert(V: *BBID);
2061
2062 for (const auto &[BBID, CallsiteIndexes] : MFPrefetchTargets) {
2063 if (MFBBIDs.contains(V: BBID))
2064 continue;
2065 for (unsigned CallsiteIndex : CallsiteIndexes)
2066 emitPrefetchTargetSymbol(BBID, CallsiteIndex);
2067 }
2068}
2069
2070/// EmitFunctionBody - This method emits the body and trailer for a
2071/// function.
2072void AsmPrinter::emitFunctionBody() {
2073 emitFunctionHeader();
2074
2075 // Emit target-specific gunk before the function body.
2076 emitFunctionBodyStart();
2077
2078 if (isVerbose()) {
2079 MDT = GetMDT(*MF);
2080 // Get MachineLoopInfo or compute it on the fly if it's unavailable, which
2081 // needs a MachineDominatorTree only for an irreducible CFG.
2082 MLI = GetMLI(*MF);
2083 if (!MLI) {
2084 OwnedMLI = std::make_unique<MachineLoopInfo>();
2085 OwnedMLI->calculate(MF&: *MF, GetDomTree: [&]() -> const MachineDominatorTree & {
2086 if (!MDT) {
2087 OwnedMDT = std::make_unique<MachineDominatorTree>();
2088 OwnedMDT->recalculate(Func&: *MF);
2089 MDT = OwnedMDT.get();
2090 }
2091 return *MDT;
2092 });
2093 MLI = OwnedMLI.get();
2094 }
2095 }
2096
2097 // Print out code for the function.
2098 bool HasAnyRealCode = false;
2099 int NumInstsInFunction = 0;
2100 // Only x86 needs this padding; the Arm unwinders back the PC up themselves.
2101 bool NeedsEHaNops = MMI->getModule()->getModuleFlag(Key: "eh-asynch") &&
2102 TM.getTargetTriple().isX86();
2103
2104 const MCSubtargetInfo *STI = nullptr;
2105 if (this->MF)
2106 STI = &getSubtargetInfo();
2107 else
2108 STI = &TM.getMCSubtargetInfo();
2109
2110 bool CanDoExtraAnalysis = ORE->allowExtraAnalysis(DEBUG_TYPE);
2111 // Create a slot for the entry basic block section so that the section
2112 // order is preserved when iterating over MBBSectionRanges.
2113 if (!MF->empty())
2114 MBBSectionRanges[MF->front().getSectionID()] =
2115 MBBSectionRange{.BeginLabel: CurrentFnBegin, .EndLabel: nullptr};
2116
2117 FunctionCallGraphInfo FuncCGInfo;
2118 const auto &CallSitesInfoMap = MF->getCallSitesInfo();
2119
2120 // Dangling targets are not mapped to any blocks and must be emitted at the
2121 // beginning of the function.
2122 emitDanglingPrefetchTargets();
2123
2124 const auto &MFPrefetchTargets = MF->getPrefetchTargets();
2125 for (auto &MBB : *MF) {
2126 // Print a label for the basic block.
2127 emitBasicBlockStart(MBB);
2128 DenseMap<StringRef, unsigned> MnemonicCounts;
2129
2130 const SmallVector<unsigned> *PrefetchTargets = nullptr;
2131 if (auto BBID = MBB.getBBID()) {
2132 auto R = MFPrefetchTargets.find(Val: *BBID);
2133 if (R != MFPrefetchTargets.end())
2134 PrefetchTargets = &R->second;
2135 }
2136 auto PrefetchTargetIt =
2137 PrefetchTargets ? PrefetchTargets->begin() : nullptr;
2138 auto PrefetchTargetEnd = PrefetchTargets ? PrefetchTargets->end() : nullptr;
2139 unsigned LastCallsiteIndex = 0;
2140
2141 for (auto &MI : MBB) {
2142 if (PrefetchTargetIt != PrefetchTargetEnd &&
2143 *PrefetchTargetIt == LastCallsiteIndex) {
2144 emitPrefetchTargetSymbol(BBID: *MBB.getBBID(), CallsiteIndex: *PrefetchTargetIt);
2145 ++PrefetchTargetIt;
2146 }
2147
2148 // Print the assembly for the instruction.
2149 if (!MI.isPosition() && !MI.isImplicitDef() && !MI.isKill() &&
2150 !MI.isDebugInstr()) {
2151 HasAnyRealCode = true;
2152 }
2153
2154 // If there is a pre-instruction symbol, emit a label for it here.
2155 if (MCSymbol *S = MI.getPreInstrSymbol())
2156 OutStreamer->emitLabel(Symbol: S);
2157
2158 if (MDNode *MD = MI.getPCSections())
2159 emitPCSectionsLabel(MF: *MF, MD: *MD);
2160
2161 for (auto &Handler : Handlers)
2162 Handler->beginInstruction(MI: &MI);
2163
2164 if (isVerbose())
2165 emitComments(MI, STI, CommentOS&: OutStreamer->getCommentOS());
2166
2167#ifndef NDEBUG
2168 MCFragment *OldFragment = OutStreamer->getCurrentFragment();
2169 size_t OldFragSize = OldFragment->getFixedSize();
2170#endif
2171
2172 switch (MI.getOpcode()) {
2173 case TargetOpcode::CFI_INSTRUCTION:
2174 emitCFIInstruction(MI);
2175 break;
2176 case TargetOpcode::LOCAL_ESCAPE:
2177 emitFrameAlloc(MI);
2178 break;
2179 case TargetOpcode::ANNOTATION_LABEL:
2180 case TargetOpcode::GC_LABEL:
2181 OutStreamer->emitLabel(Symbol: MI.getOperand(i: 0).getMCSymbol());
2182 break;
2183 case TargetOpcode::EH_LABEL:
2184 OutStreamer->AddComment(T: "EH_LABEL");
2185 OutStreamer->emitLabel(Symbol: MI.getOperand(i: 0).getMCSymbol());
2186 // For AsynchEH, insert a Nop if followed by a trap inst
2187 // Or the exception won't be caught.
2188 // (see MCConstantExpr::create(1,..) in WinException.cpp)
2189 // Ignore SDiv/UDiv because a DIV with Const-0 divisor
2190 // must have being turned into an UndefValue.
2191 // Div with variable opnds won't be the first instruction in
2192 // an EH region as it must be led by at least a Load
2193 {
2194 auto MI2 = std::next(x: MI.getIterator());
2195 if (NeedsEHaNops && MI2 != MBB.end() &&
2196 (MI2->mayLoadOrStore() || MI2->mayRaiseFPException()))
2197 emitNops(N: 1);
2198 }
2199 break;
2200 case TargetOpcode::INLINEASM:
2201 case TargetOpcode::INLINEASM_BR:
2202 emitInlineAsm(MI: &MI);
2203 break;
2204 case TargetOpcode::DBG_VALUE:
2205 case TargetOpcode::DBG_VALUE_LIST:
2206 if (isVerbose()) {
2207 if (!emitDebugValueComment(MI: &MI, AP&: *this))
2208 emitInstruction(&MI);
2209 }
2210 break;
2211 case TargetOpcode::DBG_INSTR_REF:
2212 // This instruction reference will have been resolved to a machine
2213 // location, and a nearby DBG_VALUE created. We can safely ignore
2214 // the instruction reference.
2215 break;
2216 case TargetOpcode::DBG_PHI:
2217 // This instruction is only used to label a program point, it's purely
2218 // meta information.
2219 break;
2220 case TargetOpcode::DBG_LABEL:
2221 if (isVerbose()) {
2222 if (!emitDebugLabelComment(MI: &MI, AP&: *this))
2223 emitInstruction(&MI);
2224 }
2225 break;
2226 case TargetOpcode::IMPLICIT_DEF:
2227 if (isVerbose()) emitImplicitDef(MI: &MI);
2228 break;
2229 case TargetOpcode::KILL:
2230 if (isVerbose()) emitKill(MI: &MI, AP&: *this);
2231 break;
2232 case TargetOpcode::FAKE_USE:
2233 if (isVerbose())
2234 emitFakeUse(MI: &MI, AP&: *this);
2235 break;
2236 case TargetOpcode::PSEUDO_PROBE:
2237 emitPseudoProbe(MI);
2238 break;
2239 case TargetOpcode::ARITH_FENCE:
2240 if (isVerbose())
2241 OutStreamer->emitRawComment(T: "ARITH_FENCE");
2242 break;
2243 case TargetOpcode::MEMBARRIER:
2244 OutStreamer->emitRawComment(T: "MEMBARRIER");
2245 break;
2246 case TargetOpcode::JUMP_TABLE_DEBUG_INFO:
2247 // This instruction is only used to note jump table debug info, it's
2248 // purely meta information.
2249 break;
2250 case TargetOpcode::INIT_UNDEF:
2251 // This is only used to influence register allocation behavior, no
2252 // actual initialization is needed.
2253 break;
2254 case TargetOpcode::RELOC_NONE: {
2255 // Generate a temporary label for the current PC.
2256 MCSymbol *Sym = OutContext.createTempSymbol(Name: "reloc_none");
2257 OutStreamer->emitLabel(Symbol: Sym);
2258 const MCExpr *Dot = MCSymbolRefExpr::create(Symbol: Sym, Ctx&: OutContext);
2259 const MCExpr *Value = MCSymbolRefExpr::create(
2260 Symbol: OutContext.getOrCreateSymbol(Name: MI.getOperand(i: 0).getSymbolName()),
2261 Ctx&: OutContext);
2262 OutStreamer->emitRelocDirective(Offset: *Dot, Name: "BFD_RELOC_NONE", Expr: Value, Loc: SMLoc());
2263 break;
2264 }
2265 default:
2266 emitInstruction(&MI);
2267
2268 auto CountInstruction = [&](const MachineInstr &MI) {
2269 // Skip Meta instructions inside bundles.
2270 if (MI.isMetaInstruction())
2271 return;
2272 ++NumInstsInFunction;
2273 if (CanDoExtraAnalysis) {
2274 StringRef Name = getMIMnemonic(MI, Streamer&: *OutStreamer);
2275 ++MnemonicCounts[Name];
2276 }
2277 };
2278 if (!MI.isBundle()) {
2279 CountInstruction(MI);
2280 break;
2281 }
2282 // Separately count all the instructions in a bundle.
2283 for (auto It = std::next(x: MI.getIterator());
2284 It != MBB.end() && It->isInsideBundle(); ++It) {
2285 CountInstruction(*It);
2286 }
2287 break;
2288 }
2289
2290#ifndef NDEBUG
2291 // Verify that the instruction size reported by InstrInfo matches the
2292 // actually emitted size. Many backends performing branch relaxation
2293 // on the MIR level rely on this for correctness.
2294 // TODO: We currently can't distinguish whether a parse error occurred
2295 // when handling INLINEASM.
2296 if (OutStreamer->isObj() && !OutContext.hadError() &&
2297 (MI.getOpcode() != TargetOpcode::INLINEASM &&
2298 MI.getOpcode() != TargetOpcode::INLINEASM_BR)) {
2299 const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
2300 TargetInstrInfo::InstSizeVerifyMode Mode =
2301 TII->getInstSizeVerifyMode(MI);
2302 if (Mode != TargetInstrInfo::InstSizeVerifyMode::NoVerify) {
2303 unsigned ExpectedSize = TII->getInstSizeInBytes(MI);
2304 MCFragment *NewFragment = OutStreamer->getCurrentFragment();
2305 unsigned ActualSize;
2306 if (OldFragment == NewFragment) {
2307 ActualSize = NewFragment->getFixedSize() - OldFragSize;
2308 } else {
2309 ActualSize = OldFragment->getFixedSize() - OldFragSize;
2310 const MCFragment *F = OldFragment->getNext();
2311 for (; F != NewFragment; F = F->getNext())
2312 ActualSize += F->getFixedSize();
2313 ActualSize += NewFragment->getFixedSize();
2314 }
2315 bool AllowOverEstimate =
2316 Mode == TargetInstrInfo::InstSizeVerifyMode::AllowOverEstimate;
2317 bool Valid = AllowOverEstimate ? ActualSize <= ExpectedSize
2318 : ActualSize == ExpectedSize;
2319 if (!Valid) {
2320 dbgs() << "In function: " << MF->getName() << "\n";
2321 dbgs() << "Size mismatch for: " << MI;
2322 if (MI.isBundled()) {
2323 dbgs() << "{\n";
2324 auto It = MI.getIterator(), End = MBB.instr_end();
2325 for (++It; It != End && It->isInsideBundle(); ++It)
2326 dbgs().indent(2) << *It;
2327 dbgs() << "}\n";
2328 }
2329 dbgs() << "Expected " << (AllowOverEstimate ? "maximum" : "exact")
2330 << " size: " << ExpectedSize << "\n";
2331 dbgs() << "Actual size: " << ActualSize << "\n";
2332 abort();
2333 }
2334 }
2335 }
2336#endif
2337
2338 if (MI.isCall()) {
2339 if (MF->getTarget().Options.BBAddrMap)
2340 OutStreamer->emitLabel(Symbol: createCallsiteEndSymbol(MBB));
2341 LastCallsiteIndex++;
2342 }
2343
2344 if (TM.Options.EmitCallGraphSection && MI.isCall())
2345 handleCallsiteForCallgraph(FuncCGInfo, CallSitesInfoMap, MI);
2346
2347 // If there is a post-instruction symbol, emit a label for it here.
2348 if (MCSymbol *S = MI.getPostInstrSymbol()) {
2349 // Emit the weak symbol attribute used for the prefetch target fallback.
2350 if (TM.getTargetTriple().isOSBinFormatELF()) {
2351 MCSymbolELF *ESym = static_cast<MCSymbolELF *>(S);
2352 if (ESym->getBinding() == ELF::STB_WEAK)
2353 OutStreamer->emitSymbolAttribute(Symbol: S, Attribute: MCSA_Weak);
2354 }
2355 OutStreamer->emitLabel(Symbol: S);
2356 }
2357
2358 for (auto &Handler : Handlers)
2359 Handler->endInstruction();
2360 }
2361 // Emit the remaining prefetch targets for this block. This includes
2362 // nonexisting callsite indexes.
2363 while (PrefetchTargetIt != PrefetchTargetEnd) {
2364 emitPrefetchTargetSymbol(BBID: *MBB.getBBID(), CallsiteIndex: *PrefetchTargetIt);
2365 ++PrefetchTargetIt;
2366 }
2367
2368 // We must emit temporary symbol for the end of this basic block, if either
2369 // we have BBLabels enabled or if this basic blocks marks the end of a
2370 // section.
2371 if (MF->getTarget().Options.BBAddrMap ||
2372 (MAI.hasDotTypeDotSizeDirective() && MBB.isEndSection()))
2373 OutStreamer->emitLabel(Symbol: MBB.getEndSymbol());
2374
2375 if (MBB.isEndSection()) {
2376 // The size directive for the section containing the entry block is
2377 // handled separately by the function section.
2378 if (!MBB.sameSection(MBB: &MF->front())) {
2379 if (MAI.hasDotTypeDotSizeDirective()) {
2380 // Emit the size directive for the basic block section.
2381 const MCExpr *SizeExp = MCBinaryExpr::createSub(
2382 LHS: MCSymbolRefExpr::create(Symbol: MBB.getEndSymbol(), Ctx&: OutContext),
2383 RHS: MCSymbolRefExpr::create(Symbol: CurrentSectionBeginSym, Ctx&: OutContext),
2384 Ctx&: OutContext);
2385 OutStreamer->emitELFSize(Symbol: CurrentSectionBeginSym, Value: SizeExp);
2386 }
2387 assert(!MBBSectionRanges.contains(MBB.getSectionID()) &&
2388 "Overwrite section range");
2389 MBBSectionRanges[MBB.getSectionID()] =
2390 MBBSectionRange{.BeginLabel: CurrentSectionBeginSym, .EndLabel: MBB.getEndSymbol()};
2391 }
2392 }
2393 emitBasicBlockEnd(MBB);
2394
2395 if (CanDoExtraAnalysis) {
2396 // Skip empty blocks.
2397 if (MBB.empty())
2398 continue;
2399
2400 MachineOptimizationRemarkAnalysis R(DEBUG_TYPE, "InstructionMix",
2401 MBB.begin()->getDebugLoc(), &MBB);
2402
2403 // Generate instruction mix remark. First, sort counts in descending order
2404 // by count and name.
2405 SmallVector<std::pair<StringRef, unsigned>, 128> MnemonicVec;
2406 for (auto &KV : MnemonicCounts)
2407 MnemonicVec.emplace_back(Args&: KV.first, Args&: KV.second);
2408
2409 sort(C&: MnemonicVec, Comp: [](const std::pair<StringRef, unsigned> &A,
2410 const std::pair<StringRef, unsigned> &B) {
2411 if (A.second > B.second)
2412 return true;
2413 if (A.second == B.second)
2414 return StringRef(A.first) < StringRef(B.first);
2415 return false;
2416 });
2417 R << "BasicBlock: " << ore::NV("BasicBlock", MBB.getName()) << "\n";
2418 for (auto &KV : MnemonicVec) {
2419 auto Name = (Twine("INST_") + getToken(Source: KV.first.trim()).first).str();
2420 R << KV.first << ": " << ore::NV(Name, KV.second) << "\n";
2421 }
2422 ORE->emit(OptDiag&: R);
2423 }
2424 }
2425
2426 EmittedInsts += NumInstsInFunction;
2427 MachineOptimizationRemarkAnalysis R(DEBUG_TYPE, "InstructionCount",
2428 MF->getFunction().getSubprogram(),
2429 &MF->front());
2430 R << ore::NV("NumInstructions", NumInstsInFunction)
2431 << " instructions in function";
2432 ORE->emit(OptDiag&: R);
2433
2434 if (ORE->allowExtraAnalysis(PassName: "target-features")) {
2435 const Function &F = MF->getFunction();
2436 std::string FunctionName;
2437 raw_string_ostream OS(FunctionName);
2438 F.printAsOperand(O&: OS, /*PrintType=*/false);
2439
2440 MachineOptimizationRemarkAnalysis Remark(
2441 "target-features", "EnabledFeatures", F.getSubprogram(), &MF->front());
2442 Remark << "Enabled features for " << ore::NV("Function", FunctionName)
2443 << ": ";
2444 // The processor feature table is sorted by feature name.
2445 ListSeparator LS(",");
2446 for (const auto *Feature : MF->getSubtarget().getEnabledProcessorFeatures())
2447 Remark << LS << ore::NV("Feature", Feature->key());
2448 ORE->emit(OptDiag&: Remark);
2449 }
2450
2451 // If the function is empty and the object file uses .subsections_via_symbols,
2452 // then we need to emit *something* to the function body to prevent the
2453 // labels from collapsing together. Just emit a noop.
2454 // Similarly, don't emit empty functions on Windows either. It can lead to
2455 // duplicate entries (two functions with the same RVA) in the Guard CF Table
2456 // after linking, causing the kernel not to load the binary:
2457 // https://developercommunity.visualstudio.com/content/problem/45366/vc-linker-creates-invalid-dll-with-clang-cl.html
2458 // FIXME: Hide this behind some API in e.g. MCAsmInfo or MCTargetStreamer.
2459 const Triple &TT = TM.getTargetTriple();
2460 if (!HasAnyRealCode && (MAI.hasSubsectionsViaSymbols() ||
2461 (TT.isOSWindows() && TT.isOSBinFormatCOFF()))) {
2462 MCInst Noop = MF->getSubtarget().getInstrInfo()->getNop();
2463
2464 // Targets can opt-out of emitting the noop here by leaving the opcode
2465 // unspecified.
2466 if (Noop.getOpcode()) {
2467 OutStreamer->AddComment(T: "avoids zero-length function");
2468 emitNops(N: 1);
2469 }
2470 }
2471
2472 // Switch to the original section in case basic block sections was used.
2473 OutStreamer->switchSection(Section: MF->getSection());
2474
2475 const Function &F = MF->getFunction();
2476 for (const auto &BB : F) {
2477 if (!BB.hasAddressTaken())
2478 continue;
2479 MCSymbol *Sym = GetBlockAddressSymbol(BB: &BB);
2480 if (Sym->isDefined())
2481 continue;
2482 OutStreamer->AddComment(T: "Address of block that was removed by CodeGen");
2483 OutStreamer->emitLabel(Symbol: Sym);
2484 }
2485
2486 // Emit target-specific gunk after the function body.
2487 emitFunctionBodyEnd();
2488
2489 // Tail-pad functions that want it.
2490 if (F.hasFnAttribute(Kind: "tail-pad-to-size")) {
2491 auto *FnEndSym = createTempSymbol(Name: "tail_pad_start");
2492 OutStreamer->emitLabel(Symbol: FnEndSym);
2493
2494 uint64_t PadToSize = F.getFnAttributeAsParsedInteger(Kind: "tail-pad-to-size");
2495 uint64_t FillValue =
2496 PadToSize ? F.getFnAttributeAsParsedInteger(Kind: "tail-pad-value") : 0;
2497
2498 // .fill ((PadToSize - FuncSize) & (PadToSize - FuncSize >= 0)) FillValue
2499 const MCExpr *FuncSize = MCBinaryExpr::createSub(
2500 LHS: MCSymbolRefExpr::create(Symbol: FnEndSym, Ctx&: OutContext),
2501 RHS: MCSymbolRefExpr::create(Symbol: CurrentFnSymForSize, Ctx&: OutContext), Ctx&: OutContext);
2502 const MCExpr *SizeConst = MCConstantExpr::create(Value: PadToSize, Ctx&: OutContext);
2503 const MCExpr *Zero = MCConstantExpr::create(Value: 0, Ctx&: OutContext);
2504 const MCExpr *SubExpr =
2505 MCBinaryExpr::createSub(LHS: SizeConst, RHS: FuncSize, Ctx&: OutContext);
2506 const MCExpr *Cmp = MCBinaryExpr::createGTE(LHS: SubExpr, RHS: Zero, Ctx&: OutContext);
2507 const MCExpr *FillExpr = MCBinaryExpr::createAnd(LHS: SubExpr, RHS: Cmp, Ctx&: OutContext);
2508 OutStreamer->emitFill(NumBytes: *FillExpr, FillValue);
2509 }
2510
2511 // Even though wasm supports .type and .size in general, function symbols
2512 // are automatically sized.
2513 bool EmitFunctionSize = MAI.hasDotTypeDotSizeDirective() && !TT.isWasm();
2514
2515 // SPIR-V supports label instructions only inside a block, not after the
2516 // function body.
2517 if (TT.getObjectFormat() != Triple::SPIRV &&
2518 (EmitFunctionSize || needFuncLabels(MF: *MF, Asm: *this) || CurrentFnEnd)) {
2519 // Create a symbol for the end of function, if not already pre-created
2520 // (e.g. for .prefalign directive).
2521 if (!CurrentFnEnd)
2522 CurrentFnEnd = createTempSymbol(Name: "func_end");
2523 OutStreamer->emitLabel(Symbol: CurrentFnEnd);
2524 }
2525
2526 // If the target wants a .size directive for the size of the function, emit
2527 // it.
2528 if (EmitFunctionSize) {
2529 // We can get the size as difference between the function label and the
2530 // temp label.
2531 const MCExpr *SizeExp = MCBinaryExpr::createSub(
2532 LHS: MCSymbolRefExpr::create(Symbol: CurrentFnEnd, Ctx&: OutContext),
2533 RHS: MCSymbolRefExpr::create(Symbol: CurrentFnSymForSize, Ctx&: OutContext), Ctx&: OutContext);
2534 OutStreamer->emitELFSize(Symbol: CurrentFnSym, Value: SizeExp);
2535 if (CurrentFnBeginLocal)
2536 OutStreamer->emitELFSize(Symbol: CurrentFnBeginLocal, Value: SizeExp);
2537 }
2538
2539 // Call endBasicBlockSection on the last block now, if it wasn't already
2540 // called.
2541 if (!MF->back().isEndSection()) {
2542 for (auto &Handler : Handlers)
2543 Handler->endBasicBlockSection(MBB: MF->back());
2544 for (auto &Handler : EHHandlers)
2545 Handler->endBasicBlockSection(MBB: MF->back());
2546 }
2547 for (auto &Handler : Handlers)
2548 Handler->markFunctionEnd();
2549 for (auto &Handler : EHHandlers)
2550 Handler->markFunctionEnd();
2551 // Update the end label of the entry block's section.
2552 MBBSectionRanges[MF->front().getSectionID()].EndLabel = CurrentFnEnd;
2553
2554 // Print out jump tables referenced by the function.
2555 emitJumpTableInfo();
2556
2557 // Emit post-function debug and/or EH information.
2558 for (auto &Handler : Handlers)
2559 Handler->endFunction(MF);
2560 for (auto &Handler : EHHandlers)
2561 Handler->endFunction(MF);
2562
2563 // Emit section containing BB address offsets and their metadata, when
2564 // BB labels are requested for this function. Skip empty functions.
2565 if (HasAnyRealCode) {
2566 if (MF->getTarget().Options.BBAddrMap)
2567 emitBBAddrMapSection(MF: *MF);
2568 else if (PgoAnalysisMapFeatures.getBits() != 0)
2569 MF->getContext().reportWarning(
2570 L: SMLoc(), Msg: "pgo-analysis-map is enabled for function " + MF->getName() +
2571 " but it does not have labels");
2572 }
2573
2574 // Emit sections containing instruction and function PCs.
2575 emitPCSections(MF: *MF);
2576
2577 // Emit section containing stack size metadata.
2578 emitStackSizeSection(MF: *MF);
2579
2580 // Emit section containing call graph metadata.
2581 emitCallGraphSection(MF: *MF, FuncCGInfo);
2582
2583 // Emit .su file containing function stack size information.
2584 emitStackUsage(MF: *MF);
2585
2586 emitPatchableFunctionEntries();
2587
2588 if (isVerbose())
2589 OutStreamer->getCommentOS() << "-- End function\n";
2590
2591 OutStreamer->addBlankLine();
2592}
2593
2594/// Compute the number of Global Variables that uses a Constant.
2595static unsigned getNumGlobalVariableUses(const Constant *C,
2596 bool &HasNonGlobalUsers) {
2597 if (!C) {
2598 HasNonGlobalUsers = true;
2599 return 0;
2600 }
2601
2602 if (isa<GlobalVariable>(Val: C))
2603 return 1;
2604
2605 unsigned NumUses = 0;
2606 for (const auto *CU : C->users())
2607 NumUses +=
2608 getNumGlobalVariableUses(C: dyn_cast<Constant>(Val: CU), HasNonGlobalUsers);
2609
2610 return NumUses;
2611}
2612
2613/// Only consider global GOT equivalents if at least one user is a
2614/// cstexpr inside an initializer of another global variables. Also, don't
2615/// handle cstexpr inside instructions. During global variable emission,
2616/// candidates are skipped and are emitted later in case at least one cstexpr
2617/// isn't replaced by a PC relative GOT entry access.
2618static bool isGOTEquivalentCandidate(const GlobalVariable *GV,
2619 unsigned &NumGOTEquivUsers,
2620 bool &HasNonGlobalUsers) {
2621 // Global GOT equivalents are unnamed private globals with a constant
2622 // pointer initializer to another global symbol. They must point to a
2623 // GlobalVariable or Function, i.e., as GlobalValue.
2624 if (!GV->hasGlobalUnnamedAddr() || !GV->hasInitializer() ||
2625 !GV->isConstant() || !GV->isDiscardableIfUnused() ||
2626 !isa<GlobalValue>(Val: GV->getOperand(i_nocapture: 0)))
2627 return false;
2628
2629 // To be a got equivalent, at least one of its users need to be a constant
2630 // expression used by another global variable.
2631 for (const auto *U : GV->users())
2632 NumGOTEquivUsers +=
2633 getNumGlobalVariableUses(C: dyn_cast<Constant>(Val: U), HasNonGlobalUsers);
2634
2635 return NumGOTEquivUsers > 0;
2636}
2637
2638/// Unnamed constant global variables solely contaning a pointer to
2639/// another globals variable is equivalent to a GOT table entry; it contains the
2640/// the address of another symbol. Optimize it and replace accesses to these
2641/// "GOT equivalents" by using the GOT entry for the final global instead.
2642/// Compute GOT equivalent candidates among all global variables to avoid
2643/// emitting them if possible later on, after it use is replaced by a GOT entry
2644/// access.
2645void AsmPrinter::computeGlobalGOTEquivs(Module &M) {
2646 if (!getObjFileLowering().supportIndirectSymViaGOTPCRel())
2647 return;
2648
2649 for (const auto &G : M.globals()) {
2650 unsigned NumGOTEquivUsers = 0;
2651 bool HasNonGlobalUsers = false;
2652 if (!isGOTEquivalentCandidate(GV: &G, NumGOTEquivUsers, HasNonGlobalUsers))
2653 continue;
2654 // If non-global variables use it, we still need to emit it.
2655 // Add 1 here, then emit it in `emitGlobalGOTEquivs`.
2656 if (HasNonGlobalUsers)
2657 NumGOTEquivUsers += 1;
2658 const MCSymbol *GOTEquivSym = getSymbol(GV: &G);
2659 GlobalGOTEquivs[GOTEquivSym] = std::make_pair(x: &G, y&: NumGOTEquivUsers);
2660 }
2661}
2662
2663/// Constant expressions using GOT equivalent globals may not be eligible
2664/// for PC relative GOT entry conversion, in such cases we need to emit such
2665/// globals we previously omitted in EmitGlobalVariable.
2666void AsmPrinter::emitGlobalGOTEquivs() {
2667 if (!getObjFileLowering().supportIndirectSymViaGOTPCRel())
2668 return;
2669
2670 SmallVector<const GlobalVariable *, 8> FailedCandidates;
2671 for (auto &I : GlobalGOTEquivs) {
2672 const GlobalVariable *GV = I.second.first;
2673 unsigned Cnt = I.second.second;
2674 if (Cnt)
2675 FailedCandidates.push_back(Elt: GV);
2676 }
2677 GlobalGOTEquivs.clear();
2678
2679 for (const auto *GV : FailedCandidates)
2680 emitGlobalVariable(GV);
2681}
2682
2683void AsmPrinter::emitGlobalAlias(const Module &M, const GlobalAlias &GA) {
2684 MCSymbol *Name = getSymbol(GV: &GA);
2685 const GlobalObject *BaseObject = GA.getAliaseeObject();
2686
2687 bool IsFunction = GA.getValueType()->isFunctionTy();
2688 // Treat bitcasts of functions as functions also. This is important at least
2689 // on WebAssembly where object and function addresses can't alias each other.
2690 if (!IsFunction)
2691 IsFunction = isa_and_nonnull<Function>(Val: BaseObject);
2692
2693 // AIX's assembly directive `.set` is not usable for aliasing purpose,
2694 // so AIX has to use the extra-label-at-definition strategy. At this
2695 // point, all the extra label is emitted, we just have to emit linkage for
2696 // those labels.
2697 if (TM.getTargetTriple().isOSBinFormatXCOFF()) {
2698 // Linkage for alias of global variable has been emitted.
2699 if (isa_and_nonnull<GlobalVariable>(Val: BaseObject))
2700 return;
2701
2702 emitLinkage(GV: &GA, GVSym: Name);
2703 // If it's a function, also emit linkage for aliases of function entry
2704 // point.
2705 if (IsFunction)
2706 emitLinkage(GV: &GA,
2707 GVSym: getObjFileLowering().getFunctionEntryPointSymbol(Func: &GA, TM));
2708 return;
2709 }
2710
2711 if (GA.hasExternalLinkage() || !MAI.getWeakRefDirective())
2712 OutStreamer->emitSymbolAttribute(Symbol: Name, Attribute: MCSA_Global);
2713 else if (GA.hasWeakLinkage() || GA.hasLinkOnceLinkage())
2714 OutStreamer->emitSymbolAttribute(Symbol: Name, Attribute: MCSA_WeakReference);
2715 else
2716 assert(GA.hasLocalLinkage() && "Invalid alias linkage");
2717
2718 // Set the symbol type to function if the alias has a function type.
2719 // This affects codegen when the aliasee is not a function.
2720 if (IsFunction) {
2721 OutStreamer->emitSymbolAttribute(Symbol: Name, Attribute: MCSA_ELF_TypeFunction);
2722 if (TM.getTargetTriple().isOSBinFormatCOFF()) {
2723 OutStreamer->beginCOFFSymbolDef(Symbol: Name);
2724 OutStreamer->emitCOFFSymbolStorageClass(
2725 StorageClass: GA.hasLocalLinkage() ? COFF::IMAGE_SYM_CLASS_STATIC
2726 : COFF::IMAGE_SYM_CLASS_EXTERNAL);
2727 OutStreamer->emitCOFFSymbolType(Type: COFF::IMAGE_SYM_DTYPE_FUNCTION
2728 << COFF::SCT_COMPLEX_TYPE_SHIFT);
2729 OutStreamer->endCOFFSymbolDef();
2730 }
2731 }
2732
2733 emitVisibility(Sym: Name, Visibility: GA.getVisibility());
2734
2735 const MCExpr *Expr = lowerConstant(CV: GA.getAliasee());
2736
2737 if (MAI.isMachO() && isa<MCBinaryExpr>(Val: Expr))
2738 OutStreamer->emitSymbolAttribute(Symbol: Name, Attribute: MCSA_AltEntry);
2739
2740 // Emit the directives as assignments aka .set:
2741 OutStreamer->emitAssignment(Symbol: Name, Value: Expr);
2742 MCSymbol *LocalAlias = getSymbolPreferLocal(GV: GA);
2743 if (LocalAlias != Name)
2744 OutStreamer->emitAssignment(Symbol: LocalAlias, Value: Expr);
2745
2746 // If the aliasee does not correspond to a symbol in the output, i.e. the
2747 // alias is not of an object or the aliased object is private, then set the
2748 // size of the alias symbol from the type of the alias. We don't do this in
2749 // other situations as the alias and aliasee having differing types but same
2750 // size may be intentional.
2751 if (MAI.hasDotTypeDotSizeDirective() && GA.getValueType()->isSized() &&
2752 (!BaseObject || BaseObject->hasPrivateLinkage())) {
2753 const DataLayout &DL = M.getDataLayout();
2754 uint64_t Size = DL.getTypeAllocSize(Ty: GA.getValueType());
2755 OutStreamer->emitELFSize(Symbol: Name, Value: MCConstantExpr::create(Value: Size, Ctx&: OutContext));
2756 }
2757}
2758
2759void AsmPrinter::emitGlobalIFunc(Module &M, const GlobalIFunc &GI) {
2760 auto EmitLinkage = [&](MCSymbol *Sym) {
2761 if (GI.hasExternalLinkage() || !MAI.getWeakRefDirective())
2762 OutStreamer->emitSymbolAttribute(Symbol: Sym, Attribute: MCSA_Global);
2763 else if (GI.hasWeakLinkage() || GI.hasLinkOnceLinkage())
2764 OutStreamer->emitSymbolAttribute(Symbol: Sym, Attribute: MCSA_WeakReference);
2765 else
2766 assert(GI.hasLocalLinkage() && "Invalid ifunc linkage");
2767 };
2768
2769 if (TM.getTargetTriple().isOSBinFormatELF()) {
2770 MCSymbol *Name = getSymbol(GV: &GI);
2771 EmitLinkage(Name);
2772 OutStreamer->emitSymbolAttribute(Symbol: Name, Attribute: MCSA_ELF_TypeIndFunction);
2773 emitVisibility(Sym: Name, Visibility: GI.getVisibility());
2774
2775 // Emit the directives as assignments aka .set:
2776 const MCExpr *Expr = lowerConstant(CV: GI.getResolver());
2777 OutStreamer->emitAssignment(Symbol: Name, Value: Expr);
2778 MCSymbol *LocalAlias = getSymbolPreferLocal(GV: GI);
2779 if (LocalAlias != Name)
2780 OutStreamer->emitAssignment(Symbol: LocalAlias, Value: Expr);
2781
2782 return;
2783 }
2784
2785 if (!TM.getTargetTriple().isOSBinFormatMachO() || !getIFuncMCSubtargetInfo())
2786 reportFatalUsageError(reason: "IFuncs are not supported on this platform");
2787
2788 // On Darwin platforms, emit a manually-constructed .symbol_resolver that
2789 // implements the symbol resolution duties of the IFunc.
2790 //
2791 // Normally, this would be handled by linker magic, but unfortunately there
2792 // are a few limitations in ld64 and ld-prime's implementation of
2793 // .symbol_resolver that mean we can't always use them:
2794 //
2795 // * resolvers cannot be the target of an alias
2796 // * resolvers cannot have private linkage
2797 // * resolvers cannot have linkonce linkage
2798 // * resolvers cannot appear in executables
2799 // * resolvers cannot appear in bundles
2800 //
2801 // This works around that by emitting a close approximation of what the
2802 // linker would have done.
2803
2804 MCSymbol *LazyPointer =
2805 GetExternalSymbolSymbol(Sym: GI.getName() + ".lazy_pointer");
2806 MCSymbol *StubHelper = GetExternalSymbolSymbol(Sym: GI.getName() + ".stub_helper");
2807
2808 OutStreamer->switchSection(Section: OutContext.getObjectFileInfo()->getDataSection());
2809
2810 const DataLayout &DL = M.getDataLayout();
2811 emitAlignment(Alignment: Align(DL.getPointerSize()));
2812 OutStreamer->emitLabel(Symbol: LazyPointer);
2813 emitVisibility(Sym: LazyPointer, Visibility: GI.getVisibility());
2814 OutStreamer->emitValue(Value: MCSymbolRefExpr::create(Symbol: StubHelper, Ctx&: OutContext), Size: 8);
2815
2816 OutStreamer->switchSection(Section: OutContext.getObjectFileInfo()->getTextSection());
2817
2818 const TargetSubtargetInfo *STI =
2819 TM.getSubtargetImpl(*GI.getResolverFunction());
2820 const TargetLowering *TLI = STI->getTargetLowering();
2821 Align TextAlign(TLI->getMinFunctionAlignment());
2822
2823 MCSymbol *Stub = getSymbol(GV: &GI);
2824 EmitLinkage(Stub);
2825 OutStreamer->emitCodeAlignment(Alignment: TextAlign, STI: *getIFuncMCSubtargetInfo());
2826 OutStreamer->emitLabel(Symbol: Stub);
2827 emitVisibility(Sym: Stub, Visibility: GI.getVisibility());
2828 emitMachOIFuncStubBody(M, GI, LazyPointer);
2829
2830 OutStreamer->emitCodeAlignment(Alignment: TextAlign, STI: *getIFuncMCSubtargetInfo());
2831 OutStreamer->emitLabel(Symbol: StubHelper);
2832 emitVisibility(Sym: StubHelper, Visibility: GI.getVisibility());
2833 emitMachOIFuncStubHelperBody(M, GI, LazyPointer);
2834}
2835
2836void AsmPrinter::emitRemarksSection(remarks::RemarkStreamer &RS) {
2837 if (!RS.wantsSection())
2838 return;
2839 if (!RS.getFilename())
2840 return;
2841
2842 MCSection *RemarksSection =
2843 OutContext.getObjectFileInfo()->getRemarksSection();
2844 if (!RemarksSection && RS.needsSection()) {
2845 OutContext.reportWarning(L: SMLoc(), Msg: "Current object file format does not "
2846 "support remarks sections.");
2847 }
2848 if (!RemarksSection)
2849 return;
2850
2851 SmallString<128> Filename = *RS.getFilename();
2852 sys::fs::make_absolute(path&: Filename);
2853 assert(!Filename.empty() && "The filename can't be empty.");
2854
2855 std::string Buf;
2856 raw_string_ostream OS(Buf);
2857
2858 remarks::RemarkSerializer &RemarkSerializer = RS.getSerializer();
2859 std::unique_ptr<remarks::MetaSerializer> MetaSerializer =
2860 RemarkSerializer.metaSerializer(OS, ExternalFilename: Filename);
2861 MetaSerializer->emit();
2862
2863 // Switch to the remarks section.
2864 OutStreamer->switchSection(Section: RemarksSection);
2865 OutStreamer->emitBinaryData(Data: Buf);
2866}
2867
2868static uint64_t globalSize(const llvm::GlobalVariable &G) {
2869 const Constant *Initializer = G.getInitializer();
2870 return G.getParent()->getDataLayout().getTypeAllocSize(
2871 Ty: Initializer->getType());
2872}
2873
2874static bool shouldTagGlobal(const llvm::GlobalVariable &G) {
2875 // We used to do this in clang, but there are optimization passes that turn
2876 // non-constant globals into constants. So now, clang only tells us whether
2877 // it would *like* a global to be tagged, but we still make the decision here.
2878 //
2879 // For now, don't instrument constant data, as it'll be in .rodata anyway. It
2880 // may be worth instrumenting these in future to stop them from being used as
2881 // gadgets.
2882 if (G.getName().starts_with(Prefix: "llvm.") || G.isThreadLocal() || G.isConstant())
2883 return false;
2884
2885 // Globals can be placed implicitly or explicitly in sections. There's two
2886 // different types of globals that meet this criteria that cause problems:
2887 // 1. Function pointers that are going into various init arrays (either
2888 // explicitly through `__attribute__((section(<foo>)))` or implicitly
2889 // through `__attribute__((constructor)))`, such as ".(pre)init(_array)",
2890 // ".fini(_array)", ".ctors", and ".dtors". These function pointers end up
2891 // overaligned and overpadded, making iterating over them problematic, and
2892 // each function pointer is individually tagged (so the iteration over
2893 // them causes SIGSEGV/MTE[AS]ERR).
2894 // 2. Global variables put into an explicit section, where the section's name
2895 // is a valid C-style identifier. The linker emits a `__start_<name>` and
2896 // `__stop_<name>` symbol for the section, so that you can iterate over
2897 // globals within this section. Unfortunately, again, these globals would
2898 // be tagged and so iteration causes SIGSEGV/MTE[AS]ERR.
2899 //
2900 // To mitigate both these cases, and because specifying a section is rare
2901 // outside of these two cases, disable MTE protection for globals in any
2902 // section.
2903 if (G.hasSection())
2904 return false;
2905
2906 return globalSize(G) > 0;
2907}
2908
2909static void tagGlobalDefinition(Module &M, GlobalVariable *G) {
2910 uint64_t SizeInBytes = globalSize(G: *G);
2911
2912 uint64_t NewSize = alignTo(Value: SizeInBytes, Align: 16);
2913 if (SizeInBytes != NewSize) {
2914 // Pad the initializer out to the next multiple of 16 bytes.
2915 llvm::SmallVector<uint8_t> Init(NewSize - SizeInBytes, 0);
2916 Constant *Padding = ConstantDataArray::get(Context&: M.getContext(), Elts&: Init);
2917 Constant *Initializer = G->getInitializer();
2918 Initializer = ConstantStruct::getAnon(V: {Initializer, Padding});
2919 auto *NewGV = new GlobalVariable(
2920 M, Initializer->getType(), G->isConstant(), G->getLinkage(),
2921 Initializer, "", G, G->getThreadLocalMode(), G->getAddressSpace());
2922 NewGV->copyAttributesFrom(Src: G);
2923 NewGV->setComdat(G->getComdat());
2924 NewGV->copyMetadata(Src: G, Offset: 0);
2925
2926 NewGV->takeName(V: G);
2927 G->replaceAllUsesWith(V: NewGV);
2928 G->eraseFromParent();
2929 G = NewGV;
2930 }
2931
2932 if (G->getAlign().valueOrOne() < 16)
2933 G->setAlignment(Align(16));
2934
2935 // Ensure that tagged globals don't get merged by ICF - as they should have
2936 // different tags at runtime.
2937 G->setUnnamedAddr(GlobalValue::UnnamedAddr::None);
2938}
2939
2940static void removeMemtagFromGlobal(GlobalVariable &G) {
2941 auto Meta = G.getSanitizerMetadata();
2942 Meta.Memtag = false;
2943 G.setSanitizerMetadata(Meta);
2944}
2945
2946bool AsmPrinter::doFinalization(Module &M) {
2947 // Set the MachineFunction to nullptr so that we can catch attempted
2948 // accesses to MF specific features at the module level and so that
2949 // we can conditionalize accesses based on whether or not it is nullptr.
2950 MF = nullptr;
2951 const Triple &Target = TM.getTargetTriple();
2952
2953 std::vector<GlobalVariable *> GlobalsToTag;
2954 for (GlobalVariable &G : M.globals()) {
2955 if (G.isDeclaration() || !G.isTagged())
2956 continue;
2957 if (!shouldTagGlobal(G)) {
2958 assert(G.hasSanitizerMetadata()); // because isTagged.
2959 removeMemtagFromGlobal(G);
2960 assert(!G.isTagged());
2961 continue;
2962 }
2963 GlobalsToTag.push_back(x: &G);
2964 }
2965 for (GlobalVariable *G : GlobalsToTag)
2966 tagGlobalDefinition(M, G);
2967
2968 // Gather all GOT equivalent globals in the module. We really need two
2969 // passes over the globals: one to compute and another to avoid its emission
2970 // in EmitGlobalVariable, otherwise we would not be able to handle cases
2971 // where the got equivalent shows up before its use.
2972 computeGlobalGOTEquivs(M);
2973
2974 // Emit global variables.
2975 for (const auto &G : M.globals())
2976 emitGlobalVariable(GV: &G);
2977
2978 // Emit remaining GOT equivalent globals.
2979 emitGlobalGOTEquivs();
2980
2981 const TargetLoweringObjectFile &TLOF = getObjFileLowering();
2982
2983 // Emit linkage(XCOFF) and visibility info for declarations
2984 for (const Function &F : M) {
2985 if (!F.isDeclarationForLinker())
2986 continue;
2987
2988 MCSymbol *Name = getSymbol(GV: &F);
2989 // Function getSymbol gives us the function descriptor symbol for XCOFF.
2990
2991 if (!Target.isOSBinFormatXCOFF()) {
2992 GlobalValue::VisibilityTypes V = F.getVisibility();
2993 if (V == GlobalValue::DefaultVisibility)
2994 continue;
2995
2996 emitVisibility(Sym: Name, Visibility: V, IsDefinition: false);
2997 continue;
2998 }
2999
3000 if (F.isIntrinsic())
3001 continue;
3002
3003 // Handle the XCOFF case.
3004 // Variable `Name` is the function descriptor symbol (see above). Get the
3005 // function entry point symbol.
3006 MCSymbol *FnEntryPointSym = TLOF.getFunctionEntryPointSymbol(Func: &F, TM);
3007 // Emit linkage for the function entry point.
3008 emitLinkage(GV: &F, GVSym: FnEntryPointSym);
3009
3010 // If a function's address is taken, which means it may be called via a
3011 // function pointer, we need the function descriptor for it.
3012 if (F.hasAddressTaken())
3013 emitLinkage(GV: &F, GVSym: Name);
3014 }
3015
3016 // Emit the remarks section contents.
3017 // FIXME: Figure out when is the safest time to emit this section. It should
3018 // not come after debug info.
3019 if (remarks::RemarkStreamer *RS = M.getContext().getMainRemarkStreamer())
3020 emitRemarksSection(RS&: *RS);
3021
3022 TLOF.emitModuleMetadata(Streamer&: *OutStreamer, M);
3023
3024 if (Target.isOSBinFormatELF()) {
3025 MachineModuleInfoELF &MMIELF = MMI->getObjFileInfo<MachineModuleInfoELF>();
3026
3027 // Output stubs for external and common global variables.
3028 MachineModuleInfoELF::SymbolListTy Stubs = MMIELF.GetGVStubList();
3029 if (!Stubs.empty()) {
3030 OutStreamer->switchSection(Section: TLOF.getDataSection());
3031 const DataLayout &DL = M.getDataLayout();
3032
3033 emitAlignment(Alignment: Align(DL.getPointerSize()));
3034 for (const auto &Stub : Stubs) {
3035 OutStreamer->emitLabel(Symbol: Stub.first);
3036 OutStreamer->emitSymbolValue(Sym: Stub.second.getPointer(),
3037 Size: DL.getPointerSize());
3038 }
3039 }
3040 }
3041
3042 if (Target.isOSBinFormatCOFF()) {
3043 MachineModuleInfoCOFF &MMICOFF =
3044 MMI->getObjFileInfo<MachineModuleInfoCOFF>();
3045
3046 // Output stubs for external and common global variables.
3047 MachineModuleInfoCOFF::SymbolListTy Stubs = MMICOFF.GetGVStubList();
3048 if (!Stubs.empty()) {
3049 const DataLayout &DL = M.getDataLayout();
3050
3051 for (const auto &Stub : Stubs) {
3052 SmallString<256> SectionName = StringRef(".rdata$");
3053 SectionName += Stub.first->getName();
3054 OutStreamer->switchSection(Section: OutContext.getCOFFSection(
3055 Section: SectionName,
3056 Characteristics: COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
3057 COFF::IMAGE_SCN_LNK_COMDAT,
3058 COMDATSymName: Stub.first->getName(), Selection: COFF::IMAGE_COMDAT_SELECT_ANY));
3059 emitAlignment(Alignment: Align(DL.getPointerSize()));
3060 OutStreamer->emitSymbolAttribute(Symbol: Stub.first, Attribute: MCSA_Global);
3061 OutStreamer->emitLabel(Symbol: Stub.first);
3062 OutStreamer->emitSymbolValue(Sym: Stub.second.getPointer(),
3063 Size: DL.getPointerSize());
3064 }
3065 }
3066 }
3067
3068 // This needs to happen before emitting debug information since that can end
3069 // arbitrary sections.
3070 if (auto *TS = OutStreamer->getTargetStreamer())
3071 TS->emitConstantPools();
3072
3073 // Emit Stack maps before any debug info. Mach-O requires that no data or
3074 // text sections come after debug info has been emitted. This matters for
3075 // stack maps as they are arbitrary data, and may even have a custom format
3076 // through user plugins.
3077 EmitStackMaps(M);
3078
3079 // Print aliases in topological order, that is, for each alias a = b,
3080 // b must be printed before a.
3081 // This is because on some targets (e.g. PowerPC) linker expects aliases in
3082 // such an order to generate correct TOC information.
3083 SmallVector<const GlobalAlias *, 16> AliasStack;
3084 SmallPtrSet<const GlobalAlias *, 16> AliasVisited;
3085 for (const auto &Alias : M.aliases()) {
3086 if (Alias.hasAvailableExternallyLinkage())
3087 continue;
3088 for (const GlobalAlias *Cur = &Alias; Cur;
3089 Cur = dyn_cast<GlobalAlias>(Val: Cur->getAliasee())) {
3090 if (!AliasVisited.insert(Ptr: Cur).second)
3091 break;
3092 AliasStack.push_back(Elt: Cur);
3093 }
3094 for (const GlobalAlias *AncestorAlias : llvm::reverse(C&: AliasStack))
3095 emitGlobalAlias(M, GA: *AncestorAlias);
3096 AliasStack.clear();
3097 }
3098
3099 // IFuncs must come before deubginfo in case the backend decides to emit them
3100 // as actual functions, since on Mach-O targets, we cannot create regular
3101 // sections after DWARF.
3102 for (const auto &IFunc : M.ifuncs())
3103 emitGlobalIFunc(M, GI: IFunc);
3104 if (TM.getTargetTriple().isOSBinFormatXCOFF() && hasDebugInfo()) {
3105 // Emit section end. This is used to tell the debug line section where the
3106 // end is for a text section if we don't use .loc to represent the debug
3107 // line.
3108 auto *Sec = OutContext.getObjectFileInfo()->getTextSection();
3109 OutStreamer->switchSectionNoPrint(Section: Sec);
3110 MCSymbol *Sym = Sec->getEndSymbol(Ctx&: OutContext);
3111 OutStreamer->emitLabel(Symbol: Sym);
3112 }
3113
3114 // Finalize debug and EH information.
3115 for (auto &Handler : Handlers)
3116 Handler->endModule();
3117 for (auto &Handler : EHHandlers)
3118 Handler->endModule();
3119
3120 // This deletes all the ephemeral handlers that AsmPrinter added, while
3121 // keeping all the user-added handlers alive until the AsmPrinter is
3122 // destroyed.
3123 EHHandlers.clear();
3124 Handlers.erase(CS: Handlers.begin() + NumUserHandlers, CE: Handlers.end());
3125 DD = nullptr;
3126
3127 // If the target wants to know about weak references, print them all.
3128 if (MAI.getWeakRefDirective()) {
3129 // FIXME: This is not lazy, it would be nice to only print weak references
3130 // to stuff that is actually used. Note that doing so would require targets
3131 // to notice uses in operands (due to constant exprs etc). This should
3132 // happen with the MC stuff eventually.
3133
3134 // Print out module-level global objects here.
3135 for (const auto &GO : M.global_objects()) {
3136 if (!GO.hasExternalWeakLinkage())
3137 continue;
3138 OutStreamer->emitSymbolAttribute(Symbol: getSymbol(GV: &GO), Attribute: MCSA_WeakReference);
3139 }
3140 if (shouldEmitWeakSwiftAsyncExtendedFramePointerFlags()) {
3141 auto SymbolName = "swift_async_extendedFramePointerFlags";
3142 auto Global = M.getGlobalVariable(Name: SymbolName);
3143 if (!Global) {
3144 auto PtrTy = PointerType::getUnqual(C&: M.getContext());
3145 Global = new GlobalVariable(M, PtrTy, false,
3146 GlobalValue::ExternalWeakLinkage, nullptr,
3147 SymbolName);
3148 OutStreamer->emitSymbolAttribute(Symbol: getSymbol(GV: Global), Attribute: MCSA_WeakReference);
3149 }
3150 }
3151 }
3152
3153 FinishGCAssembly(M);
3154
3155 // Emit llvm.ident metadata in an '.ident' directive.
3156 emitModuleIdents(M);
3157
3158 // Emit bytes for llvm.commandline metadata.
3159 // The command line metadata is emitted earlier on XCOFF.
3160 if (!Target.isOSBinFormatXCOFF())
3161 emitModuleCommandLines(M);
3162
3163 // Emit .note.GNU-split-stack and .note.GNU-no-split-stack sections if
3164 // split-stack is used.
3165 if (TM.getTargetTriple().isOSBinFormatELF() && HasSplitStack) {
3166 OutStreamer->switchSection(Section: OutContext.getELFSection(Section: ".note.GNU-split-stack",
3167 Type: ELF::SHT_PROGBITS, Flags: 0));
3168 if (HasNoSplitStack)
3169 OutStreamer->switchSection(Section: OutContext.getELFSection(
3170 Section: ".note.GNU-no-split-stack", Type: ELF::SHT_PROGBITS, Flags: 0));
3171 }
3172
3173 // If we don't have any trampolines, then we don't require stack memory
3174 // to be executable. Some targets have a directive to declare this.
3175 Function *InitTrampolineIntrinsic = M.getFunction(Name: "llvm.init.trampoline");
3176 bool HasTrampolineUses =
3177 InitTrampolineIntrinsic && !InitTrampolineIntrinsic->use_empty();
3178 MCSection *S = MAI.getStackSection(Ctx&: OutContext, /*Exec=*/HasTrampolineUses);
3179 if (S)
3180 OutStreamer->switchSection(Section: S);
3181
3182 if (TM.Options.EmitAddrsig) {
3183 // Emit address-significance attributes for all globals.
3184 OutStreamer->emitAddrsig();
3185 for (const GlobalValue &GV : M.global_values()) {
3186 if (!GV.use_empty() && !GV.isThreadLocal() &&
3187 !GV.hasDLLImportStorageClass() &&
3188 !GV.getName().starts_with(Prefix: "llvm.") &&
3189 !GV.hasAtLeastLocalUnnamedAddr())
3190 OutStreamer->emitAddrsigSym(Sym: getSymbol(GV: &GV));
3191 }
3192 }
3193
3194 // Emit symbol partition specifications (ELF only).
3195 if (Target.isOSBinFormatELF()) {
3196 unsigned UniqueID = 0;
3197 for (const GlobalValue &GV : M.global_values()) {
3198 if (!GV.hasPartition() || GV.isDeclarationForLinker() ||
3199 GV.getVisibility() != GlobalValue::DefaultVisibility)
3200 continue;
3201
3202 OutStreamer->switchSection(
3203 Section: OutContext.getELFSection(Section: ".llvm_sympart", Type: ELF::SHT_LLVM_SYMPART, Flags: 0, EntrySize: 0,
3204 Group: "", IsComdat: false, UniqueID: ++UniqueID, LinkedToSym: nullptr));
3205 OutStreamer->emitBytes(Data: GV.getPartition());
3206 OutStreamer->emitZeros(NumBytes: 1);
3207 OutStreamer->emitValue(
3208 Value: MCSymbolRefExpr::create(Symbol: getSymbol(GV: &GV), Ctx&: OutContext),
3209 Size: MAI.getCodePointerSize());
3210 }
3211 }
3212
3213 // Allow the target to emit any magic that it wants at the end of the file,
3214 // after everything else has gone out.
3215 emitEndOfAsmFile(M);
3216
3217 MMI = nullptr;
3218 AddrLabelSymbols = nullptr;
3219
3220 OutStreamer->finish();
3221 OutStreamer->reset();
3222 OwnedMLI.reset();
3223 OwnedMDT.reset();
3224
3225 return false;
3226}
3227
3228MCSymbol *AsmPrinter::getMBBExceptionSym(const MachineBasicBlock &MBB) {
3229 auto Res = MBBSectionExceptionSyms.try_emplace(Key: MBB.getSectionID());
3230 if (Res.second)
3231 Res.first->second = createTempSymbol(Name: "exception");
3232 return Res.first->second;
3233}
3234
3235MCSymbol *AsmPrinter::createCallsiteEndSymbol(const MachineBasicBlock &MBB) {
3236 MCContext &Ctx = MF->getContext();
3237 MCSymbol *Sym = Ctx.createTempSymbol(Name: "BB" + Twine(MF->getFunctionNumber()) +
3238 "_" + Twine(MBB.getNumber()) + "_CS");
3239 CurrentFnCallsiteEndSymbols[&MBB].push_back(Elt: Sym);
3240 return Sym;
3241}
3242
3243void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
3244 this->MF = &MF;
3245 const Function &F = MF.getFunction();
3246
3247 // Record that there are split-stack functions, so we will emit a special
3248 // section to tell the linker.
3249 if (MF.shouldSplitStack()) {
3250 HasSplitStack = true;
3251
3252 if (!MF.getFrameInfo().needsSplitStackProlog())
3253 HasNoSplitStack = true;
3254 } else
3255 HasNoSplitStack = true;
3256
3257 // Get the function symbol.
3258 if (!MAI.isAIX()) {
3259 CurrentFnSym = getSymbol(GV: &MF.getFunction());
3260 } else {
3261 assert(TM.getTargetTriple().isOSAIX() &&
3262 "Only AIX uses the function descriptor hooks.");
3263 // AIX is unique here in that the name of the symbol emitted for the
3264 // function body does not have the same name as the source function's
3265 // C-linkage name.
3266 assert(CurrentFnDescSym && "The function descriptor symbol needs to be"
3267 " initalized first.");
3268
3269 // Get the function entry point symbol.
3270 CurrentFnSym = getObjFileLowering().getFunctionEntryPointSymbol(Func: &F, TM);
3271 }
3272
3273 CurrentFnSymForSize = CurrentFnSym;
3274 CurrentFnBegin = nullptr;
3275 CurrentFnBeginLocal = nullptr;
3276 CurrentFnEnd = nullptr;
3277 CurrentSectionBeginSym = nullptr;
3278 CurrentFnCallsiteEndSymbols.clear();
3279 MBBSectionRanges.clear();
3280 MBBSectionExceptionSyms.clear();
3281 bool NeedsLocalForSize = MAI.needsLocalForSize();
3282 if (F.hasFnAttribute(Kind: "patchable-function-entry") ||
3283 F.hasFnAttribute(Kind: "tail-pad-to-size") ||
3284 F.hasFnAttribute(Kind: "function-instrument") ||
3285 F.hasFnAttribute(Kind: "xray-instruction-threshold") ||
3286 needFuncLabels(MF, Asm: *this) || NeedsLocalForSize ||
3287 MF.getTarget().Options.EmitStackSizeSection ||
3288 MF.getTarget().Options.EmitCallGraphSection ||
3289 MF.getTarget().Options.BBAddrMap) {
3290 CurrentFnBegin = createTempSymbol(Name: "func_begin");
3291 if (NeedsLocalForSize)
3292 CurrentFnSymForSize = CurrentFnBegin;
3293 }
3294
3295 ORE = GetORE(MF);
3296}
3297
3298namespace {
3299
3300// Keep track the alignment, constpool entries per Section.
3301 struct SectionCPs {
3302 MCSection *S;
3303 Align Alignment;
3304 SmallVector<unsigned, 4> CPEs;
3305
3306 SectionCPs(MCSection *s, Align a) : S(s), Alignment(a) {}
3307 };
3308
3309} // end anonymous namespace
3310
3311StringRef AsmPrinter::getConstantSectionSuffix(const Constant *C) const {
3312 if (TM.Options.EnableStaticDataPartitioning && C && SDPI && PSI)
3313 return SDPI->getConstantSectionPrefix(C, PSI);
3314
3315 return "";
3316}
3317
3318/// EmitConstantPool - Print to the current output stream assembly
3319/// representations of the constants in the constant pool MCP. This is
3320/// used to print out constants which have been "spilled to memory" by
3321/// the code generator.
3322void AsmPrinter::emitConstantPool() {
3323 const MachineConstantPool *MCP = MF->getConstantPool();
3324 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
3325 if (CP.empty()) return;
3326
3327 // Calculate sections for constant pool entries. We collect entries to go into
3328 // the same section together to reduce amount of section switch statements.
3329 SmallVector<SectionCPs, 4> CPSections;
3330 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
3331 const MachineConstantPoolEntry &CPE = CP[i];
3332 Align Alignment = CPE.getAlign();
3333
3334 SectionKind Kind = CPE.getSectionKind(DL: &getDataLayout());
3335
3336 const Constant *C = nullptr;
3337 if (!CPE.isMachineConstantPoolEntry())
3338 C = CPE.Val.ConstVal;
3339
3340 MCSection *S = getObjFileLowering().getSectionForConstant(
3341 DL: getDataLayout(), Kind, C, Alignment, F: &MF->getFunction(),
3342 SectionSuffix: getConstantSectionSuffix(C));
3343
3344 // The number of sections are small, just do a linear search from the
3345 // last section to the first.
3346 bool Found = false;
3347 unsigned SecIdx = CPSections.size();
3348 while (SecIdx != 0) {
3349 if (CPSections[--SecIdx].S == S) {
3350 Found = true;
3351 break;
3352 }
3353 }
3354 if (!Found) {
3355 SecIdx = CPSections.size();
3356 CPSections.push_back(Elt: SectionCPs(S, Alignment));
3357 }
3358
3359 if (Alignment > CPSections[SecIdx].Alignment)
3360 CPSections[SecIdx].Alignment = Alignment;
3361 CPSections[SecIdx].CPEs.push_back(Elt: i);
3362 }
3363
3364 // Now print stuff into the calculated sections.
3365 const MCSection *CurSection = nullptr;
3366 unsigned Offset = 0;
3367 for (const SectionCPs &CPSection : CPSections) {
3368 for (unsigned CPI : CPSection.CPEs) {
3369 MCSymbol *Sym = GetCPISymbol(CPID: CPI);
3370 if (!Sym->isUndefined())
3371 continue;
3372
3373 if (CurSection != CPSection.S) {
3374 OutStreamer->switchSection(Section: CPSection.S);
3375 emitAlignment(Alignment: Align(CPSection.Alignment));
3376 CurSection = CPSection.S;
3377 Offset = 0;
3378 }
3379
3380 MachineConstantPoolEntry CPE = CP[CPI];
3381
3382 // Emit inter-object padding for alignment.
3383 unsigned NewOffset = alignTo(Size: Offset, A: CPE.getAlign());
3384 OutStreamer->emitZeros(NumBytes: NewOffset - Offset);
3385
3386 if (MAI.hasDotTypeDotSizeDirective())
3387 OutStreamer->emitSymbolAttribute(Symbol: Sym, Attribute: MCSA_ELF_TypeObject);
3388 OutStreamer->emitLabel(Symbol: Sym);
3389
3390 if (CPE.isMachineConstantPoolEntry())
3391 emitMachineConstantPoolValue(MCPV: CPE.Val.MachineCPVal);
3392 else
3393 emitGlobalConstant(DL: getDataLayout(), CV: CPE.Val.ConstVal);
3394
3395 unsigned EntrySize = CPE.getSizeInBytes(DL: getDataLayout());
3396 if (MAI.hasDotTypeDotSizeDirective())
3397 OutStreamer->emitELFSize(Symbol: Sym,
3398 Value: MCConstantExpr::create(Value: EntrySize, Ctx&: OutContext));
3399
3400 Offset = NewOffset + EntrySize;
3401 }
3402 }
3403}
3404
3405// Print assembly representations of the jump tables used by the current
3406// function.
3407void AsmPrinter::emitJumpTableInfo() {
3408 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
3409 if (!MJTI) return;
3410
3411 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
3412 if (JT.empty()) return;
3413
3414 if (!TM.Options.EnableStaticDataPartitioning) {
3415 emitJumpTableImpl(MJTI: *MJTI, JumpTableIndices: llvm::to_vector(Range: llvm::seq<unsigned>(Size: JT.size())));
3416 return;
3417 }
3418
3419 SmallVector<unsigned> HotJumpTableIndices, ColdJumpTableIndices;
3420 // When static data partitioning is enabled, collect jump table entries that
3421 // go into the same section together to reduce the amount of section switch
3422 // statements.
3423 for (unsigned JTI = 0, JTSize = JT.size(); JTI < JTSize; ++JTI) {
3424 if (JT[JTI].Hotness == MachineFunctionDataHotness::Cold) {
3425 ColdJumpTableIndices.push_back(Elt: JTI);
3426 } else {
3427 HotJumpTableIndices.push_back(Elt: JTI);
3428 }
3429 }
3430
3431 emitJumpTableImpl(MJTI: *MJTI, JumpTableIndices: HotJumpTableIndices);
3432 emitJumpTableImpl(MJTI: *MJTI, JumpTableIndices: ColdJumpTableIndices);
3433}
3434
3435void AsmPrinter::emitJumpTableImpl(const MachineJumpTableInfo &MJTI,
3436 ArrayRef<unsigned> JumpTableIndices) {
3437 if (MJTI.getEntryKind() == MachineJumpTableInfo::EK_Inline ||
3438 JumpTableIndices.empty())
3439 return;
3440
3441 const TargetLoweringObjectFile &TLOF = getObjFileLowering();
3442 const Function &F = MF->getFunction();
3443 const std::vector<MachineJumpTableEntry> &JT = MJTI.getJumpTables();
3444 MCSection *JumpTableSection = nullptr;
3445
3446 const bool UseLabelDifference =
3447 MJTI.getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
3448 MJTI.getEntryKind() == MachineJumpTableInfo::EK_LabelDifference64;
3449 // Pick the directive to use to print the jump table entries, and switch to
3450 // the appropriate section.
3451 const bool JTInDiffSection =
3452 !TLOF.shouldPutJumpTableInFunctionSection(UsesLabelDifference: UseLabelDifference, F);
3453 if (JTInDiffSection) {
3454 if (TM.Options.EnableStaticDataPartitioning) {
3455 JumpTableSection =
3456 TLOF.getSectionForJumpTable(F, TM, JTE: &JT[JumpTableIndices.front()]);
3457 } else {
3458 JumpTableSection = TLOF.getSectionForJumpTable(F, TM);
3459 }
3460 OutStreamer->switchSection(Section: JumpTableSection);
3461 }
3462
3463 const DataLayout &DL = MF->getDataLayout();
3464 emitAlignment(Alignment: Align(MJTI.getEntryAlignment(TD: DL)));
3465
3466 // Jump tables in code sections are marked with a data_region directive
3467 // where that's supported.
3468 if (!JTInDiffSection)
3469 OutStreamer->emitDataRegion(Kind: MCDR_DataRegionJT32);
3470
3471 for (const unsigned JumpTableIndex : JumpTableIndices) {
3472 ArrayRef<MachineBasicBlock *> JTBBs = JT[JumpTableIndex].MBBs;
3473
3474 // If this jump table was deleted, ignore it.
3475 if (JTBBs.empty())
3476 continue;
3477
3478 // For the EK_LabelDifference32 entry, if using .set avoids a relocation,
3479 /// emit a .set directive for each unique entry.
3480 if (MJTI.getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
3481 MAI.doesSetDirectiveSuppressReloc()) {
3482 SmallPtrSet<const MachineBasicBlock *, 16> EmittedSets;
3483 const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
3484 const MCExpr *Base =
3485 TLI->getPICJumpTableRelocBaseExpr(MF, JTI: JumpTableIndex, Ctx&: OutContext);
3486 for (const MachineBasicBlock *MBB : JTBBs) {
3487 if (!EmittedSets.insert(Ptr: MBB).second)
3488 continue;
3489
3490 // .set LJTSet, LBB32-base
3491 const MCExpr *LHS =
3492 MCSymbolRefExpr::create(Symbol: MBB->getSymbol(), Ctx&: OutContext);
3493 OutStreamer->emitAssignment(
3494 Symbol: GetJTSetSymbol(UID: JumpTableIndex, MBBID: MBB->getNumber()),
3495 Value: MCBinaryExpr::createSub(LHS, RHS: Base, Ctx&: OutContext));
3496 }
3497 }
3498
3499 // On some targets (e.g. Darwin) we want to emit two consecutive labels
3500 // before each jump table. The first label is never referenced, but tells
3501 // the assembler and linker the extents of the jump table object. The
3502 // second label is actually referenced by the code.
3503 if (JTInDiffSection && DL.hasLinkerPrivateGlobalPrefix())
3504 // FIXME: This doesn't have to have any specific name, just any randomly
3505 // named and numbered local label started with 'l' would work. Simplify
3506 // GetJTISymbol.
3507 OutStreamer->emitLabel(Symbol: GetJTISymbol(JTID: JumpTableIndex, isLinkerPrivate: true));
3508
3509 MCSymbol *JTISymbol = GetJTISymbol(JTID: JumpTableIndex);
3510 if (JTInDiffSection && MAI.hasDotTypeDotSizeDirective())
3511 OutStreamer->emitSymbolAttribute(Symbol: JTISymbol, Attribute: MCSA_ELF_TypeObject);
3512 OutStreamer->emitLabel(Symbol: JTISymbol);
3513
3514 // Defer MCAssembler based constant folding due to a performance issue. The
3515 // label differences will be evaluated at write time.
3516 for (const MachineBasicBlock *MBB : JTBBs)
3517 emitJumpTableEntry(MJTI, MBB, uid: JumpTableIndex);
3518
3519 if (JTInDiffSection && MAI.hasDotTypeDotSizeDirective())
3520 OutStreamer->emitELFSize(
3521 Symbol: JTISymbol, Value: MCConstantExpr::create(
3522 Value: JTBBs.size() * MJTI.getEntrySize(TD: DL), Ctx&: OutContext));
3523 }
3524
3525 if (EmitJumpTableSizesSection)
3526 emitJumpTableSizesSection(MJTI, F: MF->getFunction());
3527
3528 if (!JTInDiffSection)
3529 OutStreamer->emitDataRegion(Kind: MCDR_DataRegionEnd);
3530}
3531
3532void AsmPrinter::emitJumpTableSizesSection(const MachineJumpTableInfo &MJTI,
3533 const Function &F) const {
3534 const std::vector<MachineJumpTableEntry> &JT = MJTI.getJumpTables();
3535
3536 if (JT.empty())
3537 return;
3538
3539 StringRef GroupName = F.hasComdat() ? F.getComdat()->getName() : "";
3540 MCSection *JumpTableSizesSection = nullptr;
3541 StringRef sectionName = ".llvm_jump_table_sizes";
3542
3543 bool isElf = TM.getTargetTriple().isOSBinFormatELF();
3544 bool isCoff = TM.getTargetTriple().isOSBinFormatCOFF();
3545
3546 if (!isCoff && !isElf)
3547 return;
3548
3549 if (isElf) {
3550 auto *LinkedToSym = static_cast<MCSymbolELF *>(CurrentFnSym);
3551 int Flags = F.hasComdat() ? static_cast<int>(ELF::SHF_GROUP) : 0;
3552
3553 JumpTableSizesSection = OutContext.getELFSection(
3554 Section: sectionName, Type: ELF::SHT_LLVM_JT_SIZES, Flags, EntrySize: 0, Group: GroupName, IsComdat: F.hasComdat(),
3555 UniqueID: MCSection::NonUniqueID, LinkedToSym);
3556 } else if (isCoff) {
3557 if (F.hasComdat()) {
3558 JumpTableSizesSection = OutContext.getCOFFSection(
3559 Section: sectionName,
3560 Characteristics: COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
3561 COFF::IMAGE_SCN_LNK_COMDAT | COFF::IMAGE_SCN_MEM_DISCARDABLE,
3562 COMDATSymName: F.getComdat()->getName(), Selection: COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE);
3563 } else {
3564 JumpTableSizesSection = OutContext.getCOFFSection(
3565 Section: sectionName, Characteristics: COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
3566 COFF::IMAGE_SCN_MEM_READ |
3567 COFF::IMAGE_SCN_MEM_DISCARDABLE);
3568 }
3569 }
3570
3571 OutStreamer->switchSection(Section: JumpTableSizesSection);
3572
3573 for (unsigned JTI = 0, E = JT.size(); JTI != E; ++JTI) {
3574 const std::vector<MachineBasicBlock *> &JTBBs = JT[JTI].MBBs;
3575 OutStreamer->emitSymbolValue(Sym: GetJTISymbol(JTID: JTI), Size: TM.getProgramPointerSize());
3576 OutStreamer->emitIntValue(Value: JTBBs.size(), Size: TM.getProgramPointerSize());
3577 }
3578}
3579
3580/// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
3581/// current stream.
3582void AsmPrinter::emitJumpTableEntry(const MachineJumpTableInfo &MJTI,
3583 const MachineBasicBlock *MBB,
3584 unsigned UID) const {
3585 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block");
3586 const MCExpr *Value = nullptr;
3587 switch (MJTI.getEntryKind()) {
3588 case MachineJumpTableInfo::EK_Inline:
3589 llvm_unreachable("Cannot emit EK_Inline jump table entry");
3590 case MachineJumpTableInfo::EK_GPRel32BlockAddress:
3591 case MachineJumpTableInfo::EK_GPRel64BlockAddress:
3592 llvm_unreachable("MIPS specific");
3593 case MachineJumpTableInfo::EK_Custom32:
3594 Value = MF->getSubtarget().getTargetLowering()->LowerCustomJumpTableEntry(
3595 &MJTI, MBB, UID, OutContext);
3596 break;
3597 case MachineJumpTableInfo::EK_BlockAddress:
3598 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
3599 // .word LBB123
3600 Value = MCSymbolRefExpr::create(Symbol: MBB->getSymbol(), Ctx&: OutContext);
3601 break;
3602
3603 case MachineJumpTableInfo::EK_LabelDifference32:
3604 case MachineJumpTableInfo::EK_LabelDifference64: {
3605 // Each entry is the address of the block minus the address of the jump
3606 // table. This is used for PIC jump tables where gprel32 is not supported.
3607 // e.g.:
3608 // .word LBB123 - LJTI1_2
3609 // If the .set directive avoids relocations, this is emitted as:
3610 // .set L4_5_set_123, LBB123 - LJTI1_2
3611 // .word L4_5_set_123
3612 if (MJTI.getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
3613 MAI.doesSetDirectiveSuppressReloc()) {
3614 Value = MCSymbolRefExpr::create(Symbol: GetJTSetSymbol(UID, MBBID: MBB->getNumber()),
3615 Ctx&: OutContext);
3616 break;
3617 }
3618 Value = MCSymbolRefExpr::create(Symbol: MBB->getSymbol(), Ctx&: OutContext);
3619 const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
3620 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF, JTI: UID, Ctx&: OutContext);
3621 Value = MCBinaryExpr::createSub(LHS: Value, RHS: Base, Ctx&: OutContext);
3622 break;
3623 }
3624 }
3625
3626 assert(Value && "Unknown entry kind!");
3627
3628 unsigned EntrySize = MJTI.getEntrySize(TD: getDataLayout());
3629 OutStreamer->emitValue(Value, Size: EntrySize);
3630}
3631
3632/// EmitSpecialLLVMGlobal - Check to see if the specified global is a
3633/// special global used by LLVM. If so, emit it and return true, otherwise
3634/// do nothing and return false.
3635bool AsmPrinter::emitSpecialLLVMGlobal(const GlobalVariable *GV) {
3636 if (GV->getName() == "llvm.used") {
3637 if (MAI.hasNoDeadStrip()) // No need to emit this at all.
3638 emitLLVMUsedList(InitList: cast<ConstantArray>(Val: GV->getInitializer()));
3639 return true;
3640 }
3641
3642 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
3643 if (GV->getSection() == "llvm.metadata" ||
3644 GV->hasAvailableExternallyLinkage())
3645 return true;
3646
3647 if (GV->getName() == "llvm.arm64ec.symbolmap") {
3648 // For ARM64EC, print the table that maps between symbols and the
3649 // corresponding thunks to translate between x64 and AArch64 code.
3650 // This table is generated by AArch64Arm64ECCallLowering.
3651 OutStreamer->switchSection(
3652 Section: OutContext.getCOFFSection(Section: ".hybmp$x", Characteristics: COFF::IMAGE_SCN_LNK_INFO));
3653 auto *Arr = cast<ConstantArray>(Val: GV->getInitializer());
3654 for (auto &U : Arr->operands()) {
3655 auto *C = cast<Constant>(Val: U);
3656 auto *Src = cast<GlobalValue>(Val: C->getOperand(i: 0)->stripPointerCasts());
3657 auto *Dst = cast<GlobalValue>(Val: C->getOperand(i: 1)->stripPointerCasts());
3658 int Kind = cast<ConstantInt>(Val: C->getOperand(i: 2))->getZExtValue();
3659
3660 if (Src->hasDLLImportStorageClass()) {
3661 // For now, we assume dllimport functions aren't directly called.
3662 // (We might change this later to match MSVC.)
3663 OutStreamer->emitCOFFSymbolIndex(
3664 Symbol: OutContext.getOrCreateSymbol(Name: "__imp_" + Src->getName()));
3665 OutStreamer->emitCOFFSymbolIndex(Symbol: getSymbol(GV: Dst));
3666 OutStreamer->emitInt32(Value: Kind);
3667 } else {
3668 // FIXME: For non-dllimport functions, MSVC emits the same entry
3669 // twice, for reasons I don't understand. I have to assume the linker
3670 // ignores the redundant entry; there aren't any reasonable semantics
3671 // to attach to it.
3672 OutStreamer->emitCOFFSymbolIndex(Symbol: getSymbol(GV: Src));
3673 OutStreamer->emitCOFFSymbolIndex(Symbol: getSymbol(GV: Dst));
3674 OutStreamer->emitInt32(Value: Kind);
3675 }
3676 }
3677 return true;
3678 }
3679
3680 if (!GV->hasAppendingLinkage()) return false;
3681
3682 assert(GV->hasInitializer() && "Not a special LLVM global!");
3683
3684 if (GV->getName() == "llvm.global_ctors") {
3685 emitXXStructorList(DL: GV->getDataLayout(), List: GV->getInitializer(),
3686 /* isCtor */ IsCtor: true);
3687
3688 return true;
3689 }
3690
3691 if (GV->getName() == "llvm.global_dtors") {
3692 emitXXStructorList(DL: GV->getDataLayout(), List: GV->getInitializer(),
3693 /* isCtor */ IsCtor: false);
3694
3695 return true;
3696 }
3697
3698 GV->getContext().emitError(
3699 ErrorStr: "unknown special variable with appending linkage: " +
3700 GV->getNameOrAsOperand());
3701 return true;
3702}
3703
3704/// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
3705/// global in the specified llvm.used list.
3706void AsmPrinter::emitLLVMUsedList(const ConstantArray *InitList) {
3707 // Should be an array of 'i8*'.
3708 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
3709 const GlobalValue *GV =
3710 dyn_cast<GlobalValue>(Val: InitList->getOperand(i_nocapture: i)->stripPointerCasts());
3711 if (GV)
3712 OutStreamer->emitSymbolAttribute(Symbol: getSymbol(GV), Attribute: MCSA_NoDeadStrip);
3713 }
3714}
3715
3716void AsmPrinter::preprocessXXStructorList(const DataLayout &DL,
3717 const Constant *List,
3718 SmallVector<Structor, 8> &Structors) {
3719 // Should be an array of '{ i32, void ()*, i8* }' structs. The first value is
3720 // the init priority.
3721 if (!isa<ConstantArray>(Val: List))
3722 return;
3723
3724 // Gather the structors in a form that's convenient for sorting by priority.
3725 for (Value *O : cast<ConstantArray>(Val: List)->operands()) {
3726 auto *CS = cast<ConstantStruct>(Val: O);
3727 if (CS->getOperand(i_nocapture: 1)->isNullValue())
3728 break; // Found a null terminator, skip the rest.
3729 ConstantInt *Priority = dyn_cast<ConstantInt>(Val: CS->getOperand(i_nocapture: 0));
3730 if (!Priority)
3731 continue; // Malformed.
3732 Structors.push_back(Elt: Structor());
3733 Structor &S = Structors.back();
3734 S.Priority = Priority->getLimitedValue(Limit: 65535);
3735 S.Func = CS->getOperand(i_nocapture: 1);
3736 if (!CS->getOperand(i_nocapture: 2)->isNullValue()) {
3737 if (TM.getTargetTriple().isOSAIX()) {
3738 CS->getContext().emitError(
3739 ErrorStr: "associated data of XXStructor list is not yet supported on AIX");
3740 }
3741
3742 S.ComdatKey =
3743 dyn_cast<GlobalValue>(Val: CS->getOperand(i_nocapture: 2)->stripPointerCasts());
3744 }
3745 }
3746
3747 // Emit the function pointers in the target-specific order
3748 llvm::stable_sort(Range&: Structors, C: [](const Structor &L, const Structor &R) {
3749 return L.Priority < R.Priority;
3750 });
3751}
3752
3753/// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
3754/// priority.
3755void AsmPrinter::emitXXStructorList(const DataLayout &DL, const Constant *List,
3756 bool IsCtor) {
3757 SmallVector<Structor, 8> Structors;
3758 preprocessXXStructorList(DL, List, Structors);
3759 if (Structors.empty())
3760 return;
3761
3762 // Emit the structors in reverse order if we are using the .ctor/.dtor
3763 // initialization scheme.
3764 if (!TM.Options.UseInitArray)
3765 std::reverse(first: Structors.begin(), last: Structors.end());
3766
3767 const Align Align = DL.getPointerPrefAlignment(AS: DL.getProgramAddressSpace());
3768 for (Structor &S : Structors) {
3769 const TargetLoweringObjectFile &Obj = getObjFileLowering();
3770 const MCSymbol *KeySym = nullptr;
3771 if (GlobalValue *GV = S.ComdatKey) {
3772 if (GV->isDeclarationForLinker())
3773 // If the associated variable is not defined in this module
3774 // (it might be available_externally, or have been an
3775 // available_externally definition that was dropped by the
3776 // EliminateAvailableExternally pass), some other TU
3777 // will provide its dynamic initializer.
3778 continue;
3779
3780 KeySym = getSymbol(GV);
3781 }
3782
3783 MCSection *OutputSection =
3784 (IsCtor ? Obj.getStaticCtorSection(Priority: S.Priority, KeySym)
3785 : Obj.getStaticDtorSection(Priority: S.Priority, KeySym));
3786 OutStreamer->switchSection(Section: OutputSection);
3787 if (OutStreamer->getCurrentSection() != OutStreamer->getPreviousSection())
3788 emitAlignment(Alignment: Align);
3789 emitXXStructor(DL, CV: S.Func);
3790 }
3791}
3792
3793void AsmPrinter::emitModuleIdents(Module &M) {
3794 if (!MAI.hasIdentDirective())
3795 return;
3796
3797 if (const NamedMDNode *NMD = M.getNamedMetadata(Name: "llvm.ident")) {
3798 for (const MDNode *N : NMD->operands()) {
3799 assert(N->getNumOperands() == 1 &&
3800 "llvm.ident metadata entry can have only one operand");
3801 const MDString *S = cast<MDString>(Val: N->getOperand(I: 0));
3802 OutStreamer->emitIdent(IdentString: S->getString());
3803 }
3804 }
3805}
3806
3807void AsmPrinter::emitModuleCommandLines(Module &M) {
3808 MCSection *CommandLine = getObjFileLowering().getSectionForCommandLines();
3809 if (!CommandLine)
3810 return;
3811
3812 const NamedMDNode *NMD = M.getNamedMetadata(Name: "llvm.commandline");
3813 if (!NMD || !NMD->getNumOperands())
3814 return;
3815
3816 OutStreamer->pushSection();
3817 OutStreamer->switchSection(Section: CommandLine);
3818 OutStreamer->emitZeros(NumBytes: 1);
3819 for (const MDNode *N : NMD->operands()) {
3820 assert(N->getNumOperands() == 1 &&
3821 "llvm.commandline metadata entry can have only one operand");
3822 const MDString *S = cast<MDString>(Val: N->getOperand(I: 0));
3823 OutStreamer->emitBytes(Data: S->getString());
3824 OutStreamer->emitZeros(NumBytes: 1);
3825 }
3826 OutStreamer->popSection();
3827}
3828
3829//===--------------------------------------------------------------------===//
3830// Emission and print routines
3831//
3832
3833/// Emit a byte directive and value.
3834///
3835void AsmPrinter::emitInt8(int Value) const { OutStreamer->emitInt8(Value); }
3836
3837/// Emit a short directive and value.
3838void AsmPrinter::emitInt16(int Value) const { OutStreamer->emitInt16(Value); }
3839
3840/// Emit a long directive and value.
3841void AsmPrinter::emitInt32(int Value) const { OutStreamer->emitInt32(Value); }
3842
3843/// EmitSLEB128 - emit the specified signed leb128 value.
3844void AsmPrinter::emitSLEB128(int64_t Value, const char *Desc) const {
3845 if (isVerbose() && Desc)
3846 OutStreamer->AddComment(T: Desc);
3847
3848 OutStreamer->emitSLEB128IntValue(Value);
3849}
3850
3851void AsmPrinter::emitULEB128(uint64_t Value, const char *Desc,
3852 unsigned PadTo) const {
3853 if (isVerbose() && Desc)
3854 OutStreamer->AddComment(T: Desc);
3855
3856 OutStreamer->emitULEB128IntValue(Value, PadTo);
3857}
3858
3859/// Emit a long long directive and value.
3860void AsmPrinter::emitInt64(uint64_t Value) const {
3861 OutStreamer->emitInt64(Value);
3862}
3863
3864/// Emit something like ".long Hi-Lo" where the size in bytes of the directive
3865/// is specified by Size and Hi/Lo specify the labels. This implicitly uses
3866/// .set if it avoids relocations.
3867void AsmPrinter::emitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
3868 unsigned Size) const {
3869 OutStreamer->emitAbsoluteSymbolDiff(Hi, Lo, Size);
3870}
3871
3872/// Emit something like ".uleb128 Hi-Lo".
3873void AsmPrinter::emitLabelDifferenceAsULEB128(const MCSymbol *Hi,
3874 const MCSymbol *Lo) const {
3875 OutStreamer->emitAbsoluteSymbolDiffAsULEB128(Hi, Lo);
3876}
3877
3878/// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
3879/// where the size in bytes of the directive is specified by Size and Label
3880/// specifies the label. This implicitly uses .set if it is available.
3881void AsmPrinter::emitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset,
3882 unsigned Size,
3883 bool IsSectionRelative) const {
3884 if (MAI.needsDwarfSectionOffsetDirective() && IsSectionRelative) {
3885 OutStreamer->emitCOFFSecRel32(Symbol: Label, Offset);
3886 if (Size > 4)
3887 OutStreamer->emitZeros(NumBytes: Size - 4);
3888 return;
3889 }
3890
3891 // Emit Label+Offset (or just Label if Offset is zero)
3892 const MCExpr *Expr = MCSymbolRefExpr::create(Symbol: Label, Ctx&: OutContext);
3893 if (Offset)
3894 Expr = MCBinaryExpr::createAdd(
3895 LHS: Expr, RHS: MCConstantExpr::create(Value: Offset, Ctx&: OutContext), Ctx&: OutContext);
3896
3897 OutStreamer->emitValue(Value: Expr, Size);
3898}
3899
3900//===----------------------------------------------------------------------===//
3901
3902// EmitAlignment - Emit an alignment directive to the specified power of
3903// two boundary. If a global value is specified, and if that global has
3904// an explicit alignment requested, it will override the alignment request
3905// if required for correctness.
3906Align AsmPrinter::emitAlignment(Align Alignment, const GlobalObject *GV,
3907 unsigned MaxBytesToEmit) const {
3908 if (GV)
3909 Alignment = getGVAlignment(GV, DL: GV->getDataLayout(), InAlign: Alignment);
3910
3911 if (Alignment == Align(1))
3912 return Alignment; // 1-byte aligned: no need to emit alignment.
3913
3914 if (getCurrentSection()->isText()) {
3915 const MCSubtargetInfo *STI = nullptr;
3916 if (this->MF)
3917 STI = &getSubtargetInfo();
3918 else
3919 STI = &TM.getMCSubtargetInfo();
3920 OutStreamer->emitCodeAlignment(Alignment, STI: *STI, MaxBytesToEmit);
3921 } else
3922 OutStreamer->emitValueToAlignment(Alignment, Fill: 0, FillLen: 1, MaxBytesToEmit);
3923 return Alignment;
3924}
3925
3926//===----------------------------------------------------------------------===//
3927// Constant emission.
3928//===----------------------------------------------------------------------===//
3929
3930const MCExpr *AsmPrinter::lowerConstant(const Constant *CV,
3931 const Constant *BaseCV,
3932 uint64_t Offset) {
3933 MCContext &Ctx = OutContext;
3934
3935 if (CV->isNullValue() || isa<UndefValue>(Val: CV))
3936 return MCConstantExpr::create(Value: 0, Ctx);
3937
3938 if (const ConstantInt *CI = dyn_cast<ConstantInt>(Val: CV))
3939 return MCConstantExpr::create(Value: CI->getZExtValue(), Ctx);
3940
3941 if (const ConstantByte *CB = dyn_cast<ConstantByte>(Val: CV))
3942 return MCConstantExpr::create(Value: CB->getZExtValue(), Ctx);
3943
3944 if (const ConstantPtrAuth *CPA = dyn_cast<ConstantPtrAuth>(Val: CV))
3945 return lowerConstantPtrAuth(CPA: *CPA);
3946
3947 if (const GlobalValue *GV = dyn_cast<GlobalValue>(Val: CV))
3948 return MCSymbolRefExpr::create(Symbol: getSymbol(GV), Ctx);
3949
3950 if (const BlockAddress *BA = dyn_cast<BlockAddress>(Val: CV))
3951 return lowerBlockAddressConstant(BA: *BA);
3952
3953 if (const auto *Equiv = dyn_cast<DSOLocalEquivalent>(Val: CV))
3954 return getObjFileLowering().lowerDSOLocalEquivalent(
3955 LHS: getSymbol(GV: Equiv->getGlobalValue()), RHS: nullptr, Addend: 0, PCRelativeOffset: std::nullopt, TM);
3956
3957 if (const NoCFIValue *NC = dyn_cast<NoCFIValue>(Val: CV))
3958 return MCSymbolRefExpr::create(Symbol: getSymbol(GV: NC->getGlobalValue()), Ctx);
3959
3960 const ConstantExpr *CE = dyn_cast<ConstantExpr>(Val: CV);
3961 if (!CE) {
3962 llvm_unreachable("Unknown constant value to lower!");
3963 }
3964
3965 // The constant expression opcodes are limited to those that are necessary
3966 // to represent relocations on supported targets. Expressions involving only
3967 // constant addresses are constant folded instead.
3968 switch (CE->getOpcode()) {
3969 default:
3970 break; // Error
3971 case Instruction::AddrSpaceCast: {
3972 const Constant *Op = CE->getOperand(i_nocapture: 0);
3973 unsigned DstAS = CE->getType()->getPointerAddressSpace();
3974 unsigned SrcAS = Op->getType()->getPointerAddressSpace();
3975 if (TM.isNoopAddrSpaceCast(SrcAS, DestAS: DstAS))
3976 return lowerConstant(CV: Op);
3977
3978 break; // Error
3979 }
3980 case Instruction::GetElementPtr: {
3981 // Generate a symbolic expression for the byte address
3982 APInt OffsetAI(getDataLayout().getIndexTypeSizeInBits(Ty: CE->getType()), 0);
3983 cast<GEPOperator>(Val: CE)->accumulateConstantOffset(DL: getDataLayout(), Offset&: OffsetAI);
3984
3985 const MCExpr *Base = lowerConstant(CV: CE->getOperand(i_nocapture: 0));
3986 if (!OffsetAI)
3987 return Base;
3988
3989 int64_t Offset = OffsetAI.getSExtValue();
3990 return MCBinaryExpr::createAdd(LHS: Base, RHS: MCConstantExpr::create(Value: Offset, Ctx),
3991 Ctx);
3992 }
3993
3994 case Instruction::Trunc:
3995 // We emit the value and depend on the assembler to truncate the generated
3996 // expression properly. This is important for differences between
3997 // blockaddress labels. Since the two labels are in the same function, it
3998 // is reasonable to treat their delta as a 32-bit value.
3999 [[fallthrough]];
4000 case Instruction::BitCast:
4001 return lowerConstant(CV: CE->getOperand(i_nocapture: 0), BaseCV, Offset);
4002
4003 case Instruction::IntToPtr: {
4004 const DataLayout &DL = getDataLayout();
4005
4006 // Handle casts to pointers by changing them into casts to the appropriate
4007 // integer type. This promotes constant folding and simplifies this code.
4008 Constant *Op = CE->getOperand(i_nocapture: 0);
4009 Op = ConstantFoldIntegerCast(C: Op, DestTy: DL.getIntPtrType(CV->getType()),
4010 /*IsSigned*/ false, DL);
4011 if (Op)
4012 return lowerConstant(CV: Op);
4013
4014 break; // Error
4015 }
4016
4017 case Instruction::PtrToAddr:
4018 case Instruction::PtrToInt: {
4019 const DataLayout &DL = getDataLayout();
4020
4021 // Support only foldable casts to/from pointers that can be eliminated by
4022 // changing the pointer to the appropriately sized integer type.
4023 Constant *Op = CE->getOperand(i_nocapture: 0);
4024 Type *Ty = CE->getType();
4025
4026 const MCExpr *OpExpr = lowerConstant(CV: Op);
4027
4028 // We can emit the pointer value into this slot if the slot is an
4029 // integer slot equal to the size of the pointer.
4030 //
4031 // If the pointer is larger than the resultant integer, then
4032 // as with Trunc just depend on the assembler to truncate it.
4033 if (DL.getTypeAllocSize(Ty).getFixedValue() <=
4034 DL.getTypeAllocSize(Ty: Op->getType()).getFixedValue())
4035 return OpExpr;
4036
4037 break; // Error
4038 }
4039
4040 case Instruction::Sub: {
4041 GlobalValue *LHSGV, *RHSGV;
4042 APInt LHSOffset, RHSOffset;
4043 DSOLocalEquivalent *DSOEquiv;
4044 if (IsConstantOffsetFromGlobal(C: CE->getOperand(i_nocapture: 0), GV&: LHSGV, Offset&: LHSOffset,
4045 DL: getDataLayout(), DSOEquiv: &DSOEquiv) &&
4046 IsConstantOffsetFromGlobal(C: CE->getOperand(i_nocapture: 1), GV&: RHSGV, Offset&: RHSOffset,
4047 DL: getDataLayout())) {
4048 auto *LHSSym = getSymbol(GV: LHSGV);
4049 auto *RHSSym = getSymbol(GV: RHSGV);
4050 int64_t Addend = (LHSOffset - RHSOffset).getSExtValue();
4051 std::optional<int64_t> PCRelativeOffset;
4052 if (getObjFileLowering().hasPLTPCRelative() && RHSGV == BaseCV)
4053 PCRelativeOffset = Offset;
4054
4055 // Try the generic symbol difference first.
4056 const MCExpr *Res = getObjFileLowering().lowerRelativeReference(
4057 LHS: LHSGV, RHS: RHSGV, Addend, PCRelativeOffset, TM);
4058
4059 // (ELF-specific) If the generic symbol difference does not apply, and
4060 // LHS is a dso_local_equivalent of a function, reference the PLT entry
4061 // instead. Note: A default visibility symbol is by default preemptible
4062 // during linking, and should not be referenced with PC-relative
4063 // relocations. Therefore, use a PLT relocation even if the function is
4064 // dso_local.
4065 if (DSOEquiv && TM.getTargetTriple().isOSBinFormatELF())
4066 Res = getObjFileLowering().lowerDSOLocalEquivalent(
4067 LHS: LHSSym, RHS: RHSSym, Addend, PCRelativeOffset, TM);
4068
4069 // Otherwise, return LHS-RHS+Addend.
4070 if (!Res) {
4071 Res =
4072 MCBinaryExpr::createSub(LHS: MCSymbolRefExpr::create(Symbol: LHSSym, Ctx),
4073 RHS: MCSymbolRefExpr::create(Symbol: RHSSym, Ctx), Ctx);
4074 if (Addend != 0)
4075 Res = MCBinaryExpr::createAdd(
4076 LHS: Res, RHS: MCConstantExpr::create(Value: Addend, Ctx), Ctx);
4077 }
4078 return Res;
4079 }
4080
4081 const MCExpr *LHS = lowerConstant(CV: CE->getOperand(i_nocapture: 0));
4082 const MCExpr *RHS = lowerConstant(CV: CE->getOperand(i_nocapture: 1));
4083 return MCBinaryExpr::createSub(LHS, RHS, Ctx);
4084 break;
4085 }
4086
4087 case Instruction::Add: {
4088 const MCExpr *LHS = lowerConstant(CV: CE->getOperand(i_nocapture: 0));
4089 const MCExpr *RHS = lowerConstant(CV: CE->getOperand(i_nocapture: 1));
4090 return MCBinaryExpr::createAdd(LHS, RHS, Ctx);
4091 }
4092 }
4093
4094 // If the code isn't optimized, there may be outstanding folding
4095 // opportunities. Attempt to fold the expression using DataLayout as a
4096 // last resort before giving up.
4097 Constant *C = ConstantFoldConstant(C: CE, DL: getDataLayout());
4098 if (C != CE)
4099 return lowerConstant(CV: C);
4100
4101 // Otherwise report the problem to the user.
4102 std::string S;
4103 raw_string_ostream OS(S);
4104 OS << "unsupported expression in static initializer: ";
4105 CE->printAsOperand(O&: OS, /*PrintType=*/false,
4106 M: !MF ? nullptr : MF->getFunction().getParent());
4107 CE->getContext().emitError(ErrorStr: S);
4108 return MCConstantExpr::create(Value: 0, Ctx);
4109}
4110
4111static void emitGlobalConstantImpl(const DataLayout &DL, const Constant *C,
4112 AsmPrinter &AP,
4113 const Constant *BaseCV = nullptr,
4114 uint64_t Offset = 0,
4115 AsmPrinter::AliasMapTy *AliasList = nullptr);
4116
4117static void emitGlobalConstantFP(const ConstantFP *CFP, AsmPrinter &AP);
4118static void emitGlobalConstantFP(APFloat APF, Type *ET, AsmPrinter &AP);
4119
4120/// isRepeatedByteSequence - Determine whether the given value is
4121/// composed of a repeated sequence of identical bytes and return the
4122/// byte value. If it is not a repeated sequence, return -1.
4123static int isRepeatedByteSequence(const ConstantDataSequential *V) {
4124 StringRef Data = V->getRawDataValues();
4125 assert(!Data.empty() && "Empty aggregates should be CAZ node");
4126 char C = Data[0];
4127 for (unsigned i = 1, e = Data.size(); i != e; ++i)
4128 if (Data[i] != C) return -1;
4129 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1.
4130}
4131
4132/// isRepeatedByteSequence - Determine whether the given value is
4133/// composed of a repeated sequence of identical bytes and return the
4134/// byte value. If it is not a repeated sequence, return -1.
4135static int isRepeatedByteSequence(const Value *V, const DataLayout &DL) {
4136 if (const ConstantInt *CI = dyn_cast<ConstantInt>(Val: V)) {
4137 uint64_t Size = DL.getTypeAllocSizeInBits(Ty: V->getType());
4138 assert(Size % 8 == 0);
4139
4140 // Extend the element to take zero padding into account.
4141 APInt Value = CI->getValue().zext(width: Size);
4142 if (!Value.isSplat(SplatSizeInBits: 8))
4143 return -1;
4144
4145 return Value.zextOrTrunc(width: 8).getZExtValue();
4146 }
4147 if (const ConstantArray *CA = dyn_cast<ConstantArray>(Val: V)) {
4148 // Make sure all array elements are sequences of the same repeated
4149 // byte.
4150 assert(CA->getNumOperands() != 0 && "Should be a CAZ");
4151 Constant *Op0 = CA->getOperand(i_nocapture: 0);
4152 int Byte = isRepeatedByteSequence(V: Op0, DL);
4153 if (Byte == -1)
4154 return -1;
4155
4156 // All array elements must be equal.
4157 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i)
4158 if (CA->getOperand(i_nocapture: i) != Op0)
4159 return -1;
4160 return Byte;
4161 }
4162
4163 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(Val: V))
4164 return isRepeatedByteSequence(V: CDS);
4165
4166 return -1;
4167}
4168
4169static void emitGlobalAliasInline(AsmPrinter &AP, uint64_t Offset,
4170 AsmPrinter::AliasMapTy *AliasList) {
4171 if (AliasList) {
4172 auto AliasIt = AliasList->find(Val: Offset);
4173 if (AliasIt != AliasList->end()) {
4174 for (const GlobalAlias *GA : AliasIt->second)
4175 AP.OutStreamer->emitLabel(Symbol: AP.getSymbol(GV: GA));
4176 AliasList->erase(Val: Offset);
4177 }
4178 }
4179}
4180
4181static void emitGlobalConstantDataSequential(
4182 const DataLayout &DL, const ConstantDataSequential *CDS, AsmPrinter &AP,
4183 AsmPrinter::AliasMapTy *AliasList) {
4184 // See if we can aggregate this into a .fill, if so, emit it as such.
4185 int Value = isRepeatedByteSequence(V: CDS, DL);
4186 if (Value != -1) {
4187 uint64_t Bytes = DL.getTypeAllocSize(Ty: CDS->getType());
4188 // Don't emit a 1-byte object as a .fill.
4189 if (Bytes > 1)
4190 return AP.OutStreamer->emitFill(NumBytes: Bytes, FillValue: Value);
4191 }
4192
4193 // If this can be emitted with .ascii/.asciz, emit it as such.
4194 if (CDS->isString())
4195 return AP.OutStreamer->emitBytes(Data: CDS->getAsString());
4196
4197 // Otherwise, emit the values in successive locations.
4198 uint64_t ElementByteSize = CDS->getElementByteSize();
4199 if (isa<IntegerType>(Val: CDS->getElementType()) ||
4200 isa<ByteType>(Val: CDS->getElementType())) {
4201 for (uint64_t I = 0, E = CDS->getNumElements(); I != E; ++I) {
4202 emitGlobalAliasInline(AP, Offset: ElementByteSize * I, AliasList);
4203 if (AP.isVerbose())
4204 AP.OutStreamer->getCommentOS()
4205 << format(Fmt: "0x%" PRIx64 "\n", Vals: CDS->getElementAsInteger(i: I));
4206 AP.OutStreamer->emitIntValue(Value: CDS->getElementAsInteger(i: I),
4207 Size: ElementByteSize);
4208 }
4209 } else {
4210 Type *ET = CDS->getElementType();
4211 for (uint64_t I = 0, E = CDS->getNumElements(); I != E; ++I) {
4212 emitGlobalAliasInline(AP, Offset: ElementByteSize * I, AliasList);
4213 emitGlobalConstantFP(APF: CDS->getElementAsAPFloat(i: I), ET, AP);
4214 }
4215 }
4216
4217 unsigned Size = DL.getTypeAllocSize(Ty: CDS->getType());
4218 unsigned EmittedSize =
4219 DL.getTypeAllocSize(Ty: CDS->getElementType()) * CDS->getNumElements();
4220 assert(EmittedSize <= Size && "Size cannot be less than EmittedSize!");
4221 if (unsigned Padding = Size - EmittedSize)
4222 AP.OutStreamer->emitZeros(NumBytes: Padding);
4223}
4224
4225static void emitGlobalConstantArray(const DataLayout &DL,
4226 const ConstantArray *CA, AsmPrinter &AP,
4227 const Constant *BaseCV, uint64_t Offset,
4228 AsmPrinter::AliasMapTy *AliasList) {
4229 // See if we can aggregate some values. Make sure it can be
4230 // represented as a series of bytes of the constant value.
4231 int Value = isRepeatedByteSequence(V: CA, DL);
4232
4233 if (Value != -1) {
4234 uint64_t Bytes = DL.getTypeAllocSize(Ty: CA->getType());
4235 AP.OutStreamer->emitFill(NumBytes: Bytes, FillValue: Value);
4236 } else {
4237 for (unsigned I = 0, E = CA->getNumOperands(); I != E; ++I) {
4238 emitGlobalConstantImpl(DL, C: CA->getOperand(i_nocapture: I), AP, BaseCV, Offset,
4239 AliasList);
4240 Offset += DL.getTypeAllocSize(Ty: CA->getOperand(i_nocapture: I)->getType());
4241 }
4242 }
4243}
4244
4245static void emitGlobalConstantLargeInt(const ConstantInt *CI, AsmPrinter &AP);
4246
4247static void emitGlobalConstantVector(const DataLayout &DL, const Constant *CV,
4248 AsmPrinter &AP,
4249 AsmPrinter::AliasMapTy *AliasList) {
4250 uint64_t AllocSize = DL.getTypeAllocSize(Ty: CV->getType());
4251
4252 if (CV->isNullValue())
4253 return AP.OutStreamer->emitZeros(NumBytes: AllocSize);
4254
4255 auto *VTy = cast<FixedVectorType>(Val: CV->getType());
4256 Type *ElementType = VTy->getElementType();
4257 uint64_t ElementSizeInBits = DL.getTypeSizeInBits(Ty: ElementType);
4258 uint64_t ElementAllocSizeInBits = DL.getTypeAllocSizeInBits(Ty: ElementType);
4259 uint64_t EmittedSize;
4260 if (ElementSizeInBits != ElementAllocSizeInBits) {
4261 // If the allocation size of an element is different from the size in bits,
4262 // printing each element separately will insert incorrect padding.
4263 //
4264 // The general algorithm here is complicated; instead of writing it out
4265 // here, just use the existing code in ConstantFolding.
4266 Type *IntT =
4267 IntegerType::get(C&: CV->getContext(), NumBits: DL.getTypeSizeInBits(Ty: CV->getType()));
4268 ConstantInt *CI = dyn_cast_or_null<ConstantInt>(Val: ConstantFoldConstant(
4269 C: ConstantExpr::getBitCast(C: const_cast<Constant *>(CV), Ty: IntT), DL));
4270 if (!CI) {
4271 report_fatal_error(
4272 reason: "Cannot lower vector global with unusual element type");
4273 }
4274 emitGlobalAliasInline(AP, Offset: 0, AliasList);
4275 emitGlobalConstantLargeInt(CI, AP);
4276 EmittedSize = DL.getTypeStoreSize(Ty: CV->getType());
4277 } else {
4278 for (unsigned I = 0, E = VTy->getNumElements(); I != E; ++I) {
4279 emitGlobalAliasInline(AP, Offset: AllocSize * I, AliasList);
4280 emitGlobalConstantImpl(DL, C: CV->getAggregateElement(Elt: I), AP);
4281 }
4282 EmittedSize = DL.getTypeAllocSize(Ty: ElementType) * VTy->getNumElements();
4283 }
4284
4285 if (unsigned Padding = AllocSize - EmittedSize)
4286 AP.OutStreamer->emitZeros(NumBytes: Padding);
4287}
4288
4289static void emitGlobalConstantStruct(const DataLayout &DL,
4290 const ConstantStruct *CS, AsmPrinter &AP,
4291 const Constant *BaseCV, uint64_t Offset,
4292 AsmPrinter::AliasMapTy *AliasList) {
4293 // Print the fields in successive locations. Pad to align if needed!
4294 uint64_t Size = DL.getTypeAllocSize(Ty: CS->getType());
4295 const StructLayout *Layout = DL.getStructLayout(Ty: CS->getType());
4296 uint64_t SizeSoFar = 0;
4297 for (unsigned I = 0, E = CS->getNumOperands(); I != E; ++I) {
4298 const Constant *Field = CS->getOperand(i_nocapture: I);
4299
4300 // Print the actual field value.
4301 emitGlobalConstantImpl(DL, C: Field, AP, BaseCV, Offset: Offset + SizeSoFar,
4302 AliasList);
4303
4304 // Check if padding is needed and insert one or more 0s.
4305 uint64_t FieldSize = DL.getTypeAllocSize(Ty: Field->getType());
4306 uint64_t PadSize = ((I == E - 1 ? Size : Layout->getElementOffset(Idx: I + 1)) -
4307 Layout->getElementOffset(Idx: I)) -
4308 FieldSize;
4309 SizeSoFar += FieldSize + PadSize;
4310
4311 // Insert padding - this may include padding to increase the size of the
4312 // current field up to the ABI size (if the struct is not packed) as well
4313 // as padding to ensure that the next field starts at the right offset.
4314 AP.OutStreamer->emitZeros(NumBytes: PadSize);
4315 }
4316 assert(SizeSoFar == Layout->getSizeInBytes() &&
4317 "Layout of constant struct may be incorrect!");
4318}
4319
4320static void emitGlobalConstantFP(APFloat APF, Type *ET, AsmPrinter &AP) {
4321 assert(ET && "Unknown float type");
4322 APInt API = APF.bitcastToAPInt();
4323
4324 // First print a comment with what we think the original floating-point value
4325 // should have been.
4326 if (AP.isVerbose()) {
4327 SmallString<8> StrVal;
4328 APF.toString(Str&: StrVal);
4329 ET->print(O&: AP.OutStreamer->getCommentOS());
4330 AP.OutStreamer->getCommentOS() << ' ' << StrVal << '\n';
4331 }
4332
4333 // Now iterate through the APInt chunks, emitting them in endian-correct
4334 // order, possibly with a smaller chunk at beginning/end (e.g. for x87 80-bit
4335 // floats).
4336 unsigned NumBytes = API.getBitWidth() / 8;
4337 unsigned TrailingBytes = NumBytes % sizeof(uint64_t);
4338 const uint64_t *p = API.getRawData();
4339
4340 // PPC's long double has odd notions of endianness compared to how LLVM
4341 // handles it: p[0] goes first for *big* endian on PPC.
4342 if (AP.getDataLayout().isBigEndian() && !ET->isPPC_FP128Ty()) {
4343 int Chunk = API.getNumWords() - 1;
4344
4345 if (TrailingBytes)
4346 AP.OutStreamer->emitIntValueInHexWithPadding(Value: p[Chunk--], Size: TrailingBytes);
4347
4348 for (; Chunk >= 0; --Chunk)
4349 AP.OutStreamer->emitIntValueInHexWithPadding(Value: p[Chunk], Size: sizeof(uint64_t));
4350 } else {
4351 unsigned Chunk;
4352 for (Chunk = 0; Chunk < NumBytes / sizeof(uint64_t); ++Chunk)
4353 AP.OutStreamer->emitIntValueInHexWithPadding(Value: p[Chunk], Size: sizeof(uint64_t));
4354
4355 if (TrailingBytes)
4356 AP.OutStreamer->emitIntValueInHexWithPadding(Value: p[Chunk], Size: TrailingBytes);
4357 }
4358
4359 // Emit the tail padding for the long double.
4360 const DataLayout &DL = AP.getDataLayout();
4361 AP.OutStreamer->emitZeros(NumBytes: DL.getTypeAllocSize(Ty: ET) - DL.getTypeStoreSize(Ty: ET));
4362}
4363
4364static void emitGlobalConstantFP(const ConstantFP *CFP, AsmPrinter &AP) {
4365 emitGlobalConstantFP(APF: CFP->getValueAPF(), ET: CFP->getType(), AP);
4366}
4367
4368static void emitGlobalConstantLargeAPInt(const APInt &Val,
4369 uint64_t TypeStoreSize,
4370 AsmPrinter &AP) {
4371 const DataLayout &DL = AP.getDataLayout();
4372 unsigned BitWidth = Val.getBitWidth();
4373
4374 // Copy the value as we may massage the layout for constants whose bit width
4375 // is not a multiple of 64-bits.
4376 APInt Realigned(Val);
4377 uint64_t ExtraBits = 0;
4378 unsigned ExtraBitsSize = BitWidth & 63;
4379
4380 if (ExtraBitsSize) {
4381 // The bit width of the data is not a multiple of 64-bits.
4382 // The extra bits are expected to be at the end of the chunk of the memory.
4383 // Little endian:
4384 // * Nothing to be done, just record the extra bits to emit.
4385 // Big endian:
4386 // * Record the extra bits to emit.
4387 // * Realign the raw data to emit the chunks of 64-bits.
4388 if (DL.isBigEndian()) {
4389 // Basically the structure of the raw data is a chunk of 64-bits cells:
4390 // 0 1 BitWidth / 64
4391 // [chunk1][chunk2] ... [chunkN].
4392 // The most significant chunk is chunkN and it should be emitted first.
4393 // However, due to the alignment issue chunkN contains useless bits.
4394 // Realign the chunks so that they contain only useful information:
4395 // ExtraBits 0 1 (BitWidth / 64) - 1
4396 // chu[nk1 chu][nk2 chu] ... [nkN-1 chunkN]
4397 ExtraBitsSize = alignTo(Value: ExtraBitsSize, Align: 8);
4398 ExtraBits =
4399 Realigned.getRawData()[0] & (((uint64_t)-1) >> (64 - ExtraBitsSize));
4400 if (BitWidth >= 64)
4401 Realigned.lshrInPlace(ShiftAmt: ExtraBitsSize);
4402 } else
4403 ExtraBits = Realigned.getRawData()[BitWidth / 64];
4404 }
4405
4406 // We don't expect assemblers to support data directives
4407 // for more than 64 bits, so we emit the data in at most 64-bit
4408 // quantities at a time.
4409 const uint64_t *RawData = Realigned.getRawData();
4410 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
4411 uint64_t ChunkVal = DL.isBigEndian() ? RawData[e - i - 1] : RawData[i];
4412 AP.OutStreamer->emitIntValue(Value: ChunkVal, Size: 8);
4413 }
4414
4415 if (ExtraBitsSize) {
4416 // Emit the extra bits after the 64-bits chunks.
4417
4418 // Emit a directive that fills the expected size.
4419 uint64_t Size = TypeStoreSize - (BitWidth / 64) * 8;
4420 assert(Size && Size * 8 >= ExtraBitsSize &&
4421 (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize))) ==
4422 ExtraBits &&
4423 "Directive too small for extra bits.");
4424 AP.OutStreamer->emitIntValue(Value: ExtraBits, Size);
4425 }
4426}
4427
4428static void emitGlobalConstantLargeByte(const ConstantByte *CB,
4429 AsmPrinter &AP) {
4430 emitGlobalConstantLargeAPInt(
4431 Val: CB->getValue(), TypeStoreSize: AP.getDataLayout().getTypeStoreSize(Ty: CB->getType()), AP);
4432}
4433
4434static void emitGlobalConstantLargeInt(const ConstantInt *CI, AsmPrinter &AP) {
4435 emitGlobalConstantLargeAPInt(
4436 Val: CI->getValue(), TypeStoreSize: AP.getDataLayout().getTypeStoreSize(Ty: CI->getType()), AP);
4437}
4438
4439/// Transform a not absolute MCExpr containing a reference to a GOT
4440/// equivalent global, by a target specific GOT pc relative access to the
4441/// final symbol.
4442static void handleIndirectSymViaGOTPCRel(AsmPrinter &AP, const MCExpr **ME,
4443 const Constant *BaseCst,
4444 uint64_t Offset) {
4445 // The global @foo below illustrates a global that uses a got equivalent.
4446 //
4447 // @bar = global i32 42
4448 // @gotequiv = private unnamed_addr constant i32* @bar
4449 // @foo = i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequiv to i64),
4450 // i64 ptrtoint (i32* @foo to i64))
4451 // to i32)
4452 //
4453 // The cstexpr in @foo is converted into the MCExpr `ME`, where we actually
4454 // check whether @foo is suitable to use a GOTPCREL. `ME` is usually in the
4455 // form:
4456 //
4457 // foo = cstexpr, where
4458 // cstexpr := <gotequiv> - "." + <cst>
4459 // cstexpr := <gotequiv> - (<foo> - <offset from @foo base>) + <cst>
4460 //
4461 // After canonicalization by evaluateAsRelocatable `ME` turns into:
4462 //
4463 // cstexpr := <gotequiv> - <foo> + gotpcrelcst, where
4464 // gotpcrelcst := <offset from @foo base> + <cst>
4465 MCValue MV;
4466 if (!(*ME)->evaluateAsRelocatable(Res&: MV, Asm: nullptr) || MV.isAbsolute())
4467 return;
4468 const MCSymbol *GOTEquivSym = MV.getAddSym();
4469 if (!GOTEquivSym)
4470 return;
4471
4472 // Check that GOT equivalent symbol is cached.
4473 if (!AP.GlobalGOTEquivs.count(Key: GOTEquivSym))
4474 return;
4475
4476 const GlobalValue *BaseGV = dyn_cast_or_null<GlobalValue>(Val: BaseCst);
4477 if (!BaseGV)
4478 return;
4479
4480 // Check for a valid base symbol
4481 const MCSymbol *BaseSym = AP.getSymbol(GV: BaseGV);
4482 const MCSymbol *SymB = MV.getSubSym();
4483
4484 if (!SymB || BaseSym != SymB)
4485 return;
4486
4487 // Make sure to match:
4488 //
4489 // gotpcrelcst := <offset from @foo base> + <cst>
4490 //
4491 int64_t GOTPCRelCst = Offset + MV.getConstant();
4492 if (!AP.getObjFileLowering().supportGOTPCRelWithOffset() && GOTPCRelCst != 0)
4493 return;
4494
4495 // Emit the GOT PC relative to replace the got equivalent global, i.e.:
4496 //
4497 // bar:
4498 // .long 42
4499 // gotequiv:
4500 // .quad bar
4501 // foo:
4502 // .long gotequiv - "." + <cst>
4503 //
4504 // is replaced by the target specific equivalent to:
4505 //
4506 // bar:
4507 // .long 42
4508 // foo:
4509 // .long bar@GOTPCREL+<gotpcrelcst>
4510 AsmPrinter::GOTEquivUsePair Result = AP.GlobalGOTEquivs[GOTEquivSym];
4511 const GlobalVariable *GV = Result.first;
4512 int NumUses = (int)Result.second;
4513 const GlobalValue *FinalGV = dyn_cast<GlobalValue>(Val: GV->getOperand(i_nocapture: 0));
4514 const MCSymbol *FinalSym = AP.getSymbol(GV: FinalGV);
4515 *ME = AP.getObjFileLowering().getIndirectSymViaGOTPCRel(
4516 GV: FinalGV, Sym: FinalSym, MV, Offset, MMI: AP.MMI, Streamer&: *AP.OutStreamer);
4517
4518 // Update GOT equivalent usage information
4519 --NumUses;
4520 if (NumUses >= 0)
4521 AP.GlobalGOTEquivs[GOTEquivSym] = std::make_pair(x&: GV, y&: NumUses);
4522}
4523
4524static void emitGlobalConstantImpl(const DataLayout &DL, const Constant *CV,
4525 AsmPrinter &AP, const Constant *BaseCV,
4526 uint64_t Offset,
4527 AsmPrinter::AliasMapTy *AliasList) {
4528 assert((!AliasList || AP.TM.getTargetTriple().isOSBinFormatXCOFF()) &&
4529 "AliasList only expected for XCOFF");
4530 emitGlobalAliasInline(AP, Offset, AliasList);
4531 uint64_t Size = DL.getTypeAllocSize(Ty: CV->getType());
4532
4533 // Globals with sub-elements such as combinations of arrays and structs
4534 // are handled recursively by emitGlobalConstantImpl. Keep track of the
4535 // constant symbol base and the current position with BaseCV and Offset.
4536 if (!BaseCV && CV->hasOneUse())
4537 BaseCV = dyn_cast<Constant>(Val: CV->user_back());
4538
4539 if (isa<ConstantAggregateZero>(Val: CV)) {
4540 StructType *structType;
4541 if (AliasList && (structType = llvm::dyn_cast<StructType>(Val: CV->getType()))) {
4542 unsigned numElements = {structType->getNumElements()};
4543 if (numElements != 0) {
4544 // Handle cases of aliases to direct struct elements
4545 const StructLayout *Layout = DL.getStructLayout(Ty: structType);
4546 uint64_t SizeSoFar = 0;
4547 for (unsigned int i = 0; i < numElements - 1; ++i) {
4548 uint64_t GapToNext = Layout->getElementOffset(Idx: i + 1) - SizeSoFar;
4549 AP.OutStreamer->emitZeros(NumBytes: GapToNext);
4550 SizeSoFar += GapToNext;
4551 emitGlobalAliasInline(AP, Offset: Offset + SizeSoFar, AliasList);
4552 }
4553 AP.OutStreamer->emitZeros(NumBytes: Size - SizeSoFar);
4554 return;
4555 }
4556 }
4557 return AP.OutStreamer->emitZeros(NumBytes: Size);
4558 }
4559
4560 if (isa<UndefValue>(Val: CV))
4561 return AP.OutStreamer->emitZeros(NumBytes: Size);
4562
4563 if (const ConstantInt *CI = dyn_cast<ConstantInt>(Val: CV)) {
4564 if (isa<VectorType>(Val: CV->getType()))
4565 return emitGlobalConstantVector(DL, CV, AP, AliasList);
4566
4567 const uint64_t StoreSize = DL.getTypeStoreSize(Ty: CV->getType());
4568 if (StoreSize <= 8) {
4569 if (AP.isVerbose())
4570 AP.OutStreamer->getCommentOS()
4571 << format(Fmt: "0x%" PRIx64 "\n", Vals: CI->getZExtValue());
4572 AP.OutStreamer->emitIntValue(Value: CI->getZExtValue(), Size: StoreSize);
4573 } else {
4574 emitGlobalConstantLargeInt(CI, AP);
4575 }
4576
4577 // Emit tail padding if needed
4578 if (Size != StoreSize)
4579 AP.OutStreamer->emitZeros(NumBytes: Size - StoreSize);
4580
4581 return;
4582 }
4583
4584 if (const ConstantByte *CB = dyn_cast<ConstantByte>(Val: CV)) {
4585 if (isa<VectorType>(Val: CV->getType()))
4586 return emitGlobalConstantVector(DL, CV, AP, AliasList);
4587
4588 const uint64_t StoreSize = DL.getTypeStoreSize(Ty: CV->getType());
4589 if (StoreSize <= 8) {
4590 if (AP.isVerbose())
4591 AP.OutStreamer->getCommentOS()
4592 << format(Fmt: "0x%" PRIx64 "\n", Vals: CB->getZExtValue());
4593 AP.OutStreamer->emitIntValue(Value: CB->getZExtValue(), Size: StoreSize);
4594 } else {
4595 emitGlobalConstantLargeByte(CB, AP);
4596 }
4597
4598 // Emit tail padding if needed
4599 if (Size != StoreSize)
4600 AP.OutStreamer->emitZeros(NumBytes: Size - StoreSize);
4601
4602 return;
4603 }
4604
4605 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(Val: CV)) {
4606 if (isa<VectorType>(Val: CV->getType()))
4607 return emitGlobalConstantVector(DL, CV, AP, AliasList);
4608 else
4609 return emitGlobalConstantFP(CFP, AP);
4610 }
4611
4612 if (isa<ConstantPointerNull>(Val: CV)) {
4613 AP.OutStreamer->emitIntValue(Value: 0, Size);
4614 return;
4615 }
4616
4617 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(Val: CV))
4618 return emitGlobalConstantDataSequential(DL, CDS, AP, AliasList);
4619
4620 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(Val: CV))
4621 return emitGlobalConstantArray(DL, CA: CVA, AP, BaseCV, Offset, AliasList);
4622
4623 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(Val: CV))
4624 return emitGlobalConstantStruct(DL, CS: CVS, AP, BaseCV, Offset, AliasList);
4625
4626 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(Val: CV)) {
4627 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
4628 // vectors).
4629 if (CE->getOpcode() == Instruction::BitCast)
4630 return emitGlobalConstantImpl(DL, CV: CE->getOperand(i_nocapture: 0), AP);
4631
4632 if (Size > 8) {
4633 // If the constant expression's size is greater than 64-bits, then we have
4634 // to emit the value in chunks. Try to constant fold the value and emit it
4635 // that way.
4636 Constant *New = ConstantFoldConstant(C: CE, DL);
4637 if (New != CE)
4638 return emitGlobalConstantImpl(DL, CV: New, AP);
4639 }
4640 }
4641
4642 if (isa<ConstantVector>(Val: CV))
4643 return emitGlobalConstantVector(DL, CV, AP, AliasList);
4644
4645 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
4646 // thread the streamer with EmitValue.
4647 const MCExpr *ME = AP.lowerConstant(CV, BaseCV, Offset);
4648
4649 // Since lowerConstant already folded and got rid of all IR pointer and
4650 // integer casts, detect GOT equivalent accesses by looking into the MCExpr
4651 // directly.
4652 if (AP.getObjFileLowering().supportIndirectSymViaGOTPCRel())
4653 handleIndirectSymViaGOTPCRel(AP, ME: &ME, BaseCst: BaseCV, Offset);
4654
4655 AP.OutStreamer->emitValue(Value: ME, Size);
4656}
4657
4658/// EmitGlobalConstant - Print a general LLVM constant to the .s file.
4659void AsmPrinter::emitGlobalConstant(const DataLayout &DL, const Constant *CV,
4660 AliasMapTy *AliasList) {
4661 uint64_t Size = DL.getTypeAllocSize(Ty: CV->getType());
4662 if (Size)
4663 emitGlobalConstantImpl(DL, CV, AP&: *this, BaseCV: nullptr, Offset: 0, AliasList);
4664 else if (MAI.hasSubsectionsViaSymbols()) {
4665 // If the global has zero size, emit a single byte so that two labels don't
4666 // look like they are at the same location.
4667 OutStreamer->emitIntValue(Value: 0, Size: 1);
4668 }
4669 if (!AliasList)
4670 return;
4671 // TODO: These remaining aliases are not emitted in the correct location. Need
4672 // to handle the case where the alias offset doesn't refer to any sub-element.
4673 for (auto &AliasPair : *AliasList) {
4674 for (const GlobalAlias *GA : AliasPair.second)
4675 OutStreamer->emitLabel(Symbol: getSymbol(GV: GA));
4676 }
4677}
4678
4679void AsmPrinter::emitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
4680 // Target doesn't support this yet!
4681 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
4682}
4683
4684void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
4685 if (Offset > 0)
4686 OS << '+' << Offset;
4687 else if (Offset < 0)
4688 OS << Offset;
4689}
4690
4691void AsmPrinter::emitNops(unsigned N) {
4692 MCInst Nop = MF->getSubtarget().getInstrInfo()->getNop();
4693 for (; N; --N)
4694 EmitToStreamer(S&: *OutStreamer, Inst: Nop);
4695}
4696
4697//===----------------------------------------------------------------------===//
4698// Symbol Lowering Routines.
4699//===----------------------------------------------------------------------===//
4700
4701MCSymbol *AsmPrinter::createTempSymbol(const Twine &Name) const {
4702 return OutContext.createTempSymbol(Name, AlwaysAddSuffix: true);
4703}
4704
4705MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
4706 return const_cast<AsmPrinter *>(this)->getAddrLabelSymbol(
4707 BB: BA->getBasicBlock());
4708}
4709
4710MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
4711 return const_cast<AsmPrinter *>(this)->getAddrLabelSymbol(BB);
4712}
4713
4714const MCExpr *AsmPrinter::lowerBlockAddressConstant(const BlockAddress &BA) {
4715 return MCSymbolRefExpr::create(Symbol: GetBlockAddressSymbol(BA: &BA), Ctx&: OutContext);
4716}
4717
4718/// GetCPISymbol - Return the symbol for the specified constant pool entry.
4719MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
4720 if (getSubtargetInfo().getTargetTriple().isWindowsMSVCEnvironment() ||
4721 getSubtargetInfo().getTargetTriple().isUEFI()) {
4722 const MachineConstantPoolEntry &CPE =
4723 MF->getConstantPool()->getConstants()[CPID];
4724 if (!CPE.isMachineConstantPoolEntry()) {
4725 const DataLayout &DL = MF->getDataLayout();
4726 SectionKind Kind = CPE.getSectionKind(DL: &DL);
4727 const Constant *C = CPE.Val.ConstVal;
4728 Align Alignment = CPE.Alignment;
4729 auto *S = getObjFileLowering().getSectionForConstant(
4730 DL, Kind, C, Alignment, F: &MF->getFunction());
4731 if (S && TM.getTargetTriple().isOSBinFormatCOFF()) {
4732 if (MCSymbol *Sym =
4733 static_cast<const MCSectionCOFF *>(S)->getCOMDATSymbol()) {
4734 if (Sym->isUndefined())
4735 OutStreamer->emitSymbolAttribute(Symbol: Sym, Attribute: MCSA_Global);
4736 return Sym;
4737 }
4738 }
4739 }
4740 }
4741
4742 const DataLayout &DL = getDataLayout();
4743 return OutContext.getOrCreateSymbol(Name: Twine(DL.getInternalSymbolPrefix()) +
4744 "CPI" + Twine(getFunctionNumber()) + "_" +
4745 Twine(CPID));
4746}
4747
4748/// GetJTISymbol - Return the symbol for the specified jump table entry.
4749MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
4750 return MF->getJTISymbol(JTI: JTID, Ctx&: OutContext, isLinkerPrivate);
4751}
4752
4753/// GetJTSetSymbol - Return the symbol for the specified jump table .set
4754/// FIXME: privatize to AsmPrinter.
4755MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
4756 const DataLayout &DL = getDataLayout();
4757 return OutContext.getOrCreateSymbol(Name: Twine(DL.getInternalSymbolPrefix()) +
4758 Twine(getFunctionNumber()) + "_" +
4759 Twine(UID) + "_set_" + Twine(MBBID));
4760}
4761
4762MCSymbol *AsmPrinter::getSymbolWithGlobalValueBase(const GlobalValue *GV,
4763 StringRef Suffix) const {
4764 return getObjFileLowering().getSymbolWithGlobalValueBase(GV, Suffix, TM);
4765}
4766
4767/// Return the MCSymbol for the specified ExternalSymbol.
4768MCSymbol *AsmPrinter::GetExternalSymbolSymbol(const Twine &Sym) const {
4769 SmallString<60> NameStr;
4770 Mangler::getNameWithPrefix(OutName&: NameStr, GVName: Sym, DL: getDataLayout());
4771 return OutContext.getOrCreateSymbol(Name: NameStr);
4772}
4773
4774/// PrintParentLoopComment - Print comments about parent loops of this one.
4775static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
4776 unsigned FunctionNumber) {
4777 if (!Loop) return;
4778 PrintParentLoopComment(OS, Loop: Loop->getParentLoop(), FunctionNumber);
4779 OS.indent(NumSpaces: Loop->getLoopDepth()*2)
4780 << "Parent Loop BB" << FunctionNumber << "_"
4781 << Loop->getHeader()->getNumber()
4782 << " Depth=" << Loop->getLoopDepth() << '\n';
4783}
4784
4785/// PrintChildLoopComment - Print comments about child loops within
4786/// the loop for this basic block, with nesting.
4787static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
4788 unsigned FunctionNumber) {
4789 // Add child loop information
4790 for (const MachineLoop *CL : *Loop) {
4791 OS.indent(NumSpaces: CL->getLoopDepth()*2)
4792 << "Child Loop BB" << FunctionNumber << "_"
4793 << CL->getHeader()->getNumber() << " Depth " << CL->getLoopDepth()
4794 << '\n';
4795 PrintChildLoopComment(OS, Loop: CL, FunctionNumber);
4796 }
4797}
4798
4799/// emitBasicBlockLoopComments - Pretty-print comments for basic blocks.
4800static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
4801 const MachineLoopInfo *LI,
4802 const AsmPrinter &AP) {
4803 // Add loop depth information
4804 const MachineLoop *Loop = LI->getLoopFor(BB: &MBB);
4805 if (!Loop) return;
4806
4807 MachineBasicBlock *Header = Loop->getHeader();
4808 assert(Header && "No header for loop");
4809
4810 // If this block is not a loop header, just print out what is the loop header
4811 // and return.
4812 if (Header != &MBB) {
4813 AP.OutStreamer->AddComment(T: " in Loop: Header=BB" +
4814 Twine(AP.getFunctionNumber())+"_" +
4815 Twine(Loop->getHeader()->getNumber())+
4816 " Depth="+Twine(Loop->getLoopDepth()));
4817 return;
4818 }
4819
4820 // Otherwise, it is a loop header. Print out information about child and
4821 // parent loops.
4822 raw_ostream &OS = AP.OutStreamer->getCommentOS();
4823
4824 PrintParentLoopComment(OS, Loop: Loop->getParentLoop(), FunctionNumber: AP.getFunctionNumber());
4825
4826 OS << "=>";
4827 OS.indent(NumSpaces: Loop->getLoopDepth()*2-2);
4828
4829 OS << "This ";
4830 if (Loop->isInnermost())
4831 OS << "Inner ";
4832 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
4833
4834 PrintChildLoopComment(OS, Loop, FunctionNumber: AP.getFunctionNumber());
4835}
4836
4837/// emitBasicBlockStart - This method prints the label for the specified
4838/// MachineBasicBlock, an alignment (if present) and a comment describing
4839/// it if appropriate.
4840void AsmPrinter::emitBasicBlockStart(const MachineBasicBlock &MBB) {
4841 // End the previous funclet and start a new one.
4842 if (MBB.isEHFuncletEntry()) {
4843 for (auto &Handler : Handlers) {
4844 Handler->endFunclet();
4845 Handler->beginFunclet(MBB);
4846 }
4847 for (auto &Handler : EHHandlers) {
4848 Handler->endFunclet();
4849 Handler->beginFunclet(MBB);
4850 }
4851 }
4852
4853 // Switch to a new section if this basic block must begin a section. The
4854 // entry block is always placed in the function section and is handled
4855 // separately.
4856 if (MBB.isBeginSection() && !MBB.isEntryBlock()) {
4857 OutStreamer->switchSection(
4858 Section: getObjFileLowering().getSectionForMachineBasicBlock(F: MF->getFunction(),
4859 MBB, TM));
4860 CurrentSectionBeginSym = MBB.getSymbol();
4861 }
4862
4863 for (auto &Handler : Handlers)
4864 Handler->beginCodeAlignment(MBB);
4865
4866 // Emit an alignment directive for this block, if needed.
4867 const Align Alignment = MBB.getAlignment();
4868 if (Alignment != Align(1))
4869 emitAlignment(Alignment, GV: nullptr, MaxBytesToEmit: MBB.getMaxBytesForAlignment());
4870
4871 // If the block has its address taken, emit any labels that were used to
4872 // reference the block. It is possible that there is more than one label
4873 // here, because multiple LLVM BB's may have been RAUW'd to this block after
4874 // the references were generated.
4875 if (MBB.isIRBlockAddressTaken()) {
4876 if (isVerbose())
4877 OutStreamer->AddComment(T: "Block address taken");
4878
4879 BasicBlock *BB = MBB.getAddressTakenIRBlock();
4880 assert(BB && BB->hasAddressTaken() && "Missing BB");
4881 for (MCSymbol *Sym : getAddrLabelSymbolToEmit(BB))
4882 OutStreamer->emitLabel(Symbol: Sym);
4883 } else if (isVerbose() && MBB.isMachineBlockAddressTaken()) {
4884 OutStreamer->AddComment(T: "Block address taken");
4885 } else if (isVerbose() && MBB.isInlineAsmBrIndirectTarget()) {
4886 OutStreamer->AddComment(T: "Inline asm indirect target");
4887 }
4888
4889 // Print some verbose block comments.
4890 if (isVerbose()) {
4891 if (const BasicBlock *BB = MBB.getBasicBlock()) {
4892 if (BB->hasName()) {
4893 BB->printAsOperand(O&: OutStreamer->getCommentOS(),
4894 /*PrintType=*/false, M: BB->getModule());
4895 OutStreamer->getCommentOS() << '\n';
4896 }
4897 }
4898
4899 assert(MLI != nullptr && "MachineLoopInfo should has been computed");
4900 emitBasicBlockLoopComments(MBB, LI: MLI, AP: *this);
4901 }
4902
4903 // Print the main label for the block.
4904 if (shouldEmitLabelForBasicBlock(MBB)) {
4905 if (isVerbose() && MBB.hasLabelMustBeEmitted())
4906 OutStreamer->AddComment(T: "Label of block must be emitted");
4907 OutStreamer->emitLabel(Symbol: MBB.getSymbol());
4908 } else {
4909 if (isVerbose()) {
4910 // NOTE: Want this comment at start of line, don't emit with AddComment.
4911 OutStreamer->emitRawComment(T: " %bb." + Twine(MBB.getNumber()) + ":",
4912 TabPrefix: false);
4913 }
4914 }
4915
4916 if (MBB.isEHContTarget() &&
4917 MAI.getExceptionHandlingType() == ExceptionHandling::WinEH) {
4918 OutStreamer->emitLabel(Symbol: MBB.getEHContSymbol());
4919 }
4920
4921 // With BB sections, each basic block must handle CFI information on its own
4922 // if it begins a section (Entry block call is handled separately, next to
4923 // beginFunction).
4924 if (MBB.isBeginSection() && !MBB.isEntryBlock()) {
4925 for (auto &Handler : Handlers)
4926 Handler->beginBasicBlockSection(MBB);
4927 for (auto &Handler : EHHandlers)
4928 Handler->beginBasicBlockSection(MBB);
4929 }
4930}
4931
4932void AsmPrinter::emitBasicBlockEnd(const MachineBasicBlock &MBB) {
4933 // Check if CFI information needs to be updated for this MBB with basic block
4934 // sections.
4935 if (MBB.isEndSection()) {
4936 for (auto &Handler : Handlers)
4937 Handler->endBasicBlockSection(MBB);
4938 for (auto &Handler : EHHandlers)
4939 Handler->endBasicBlockSection(MBB);
4940 }
4941}
4942
4943void AsmPrinter::emitVisibility(MCSymbol *Sym, unsigned Visibility,
4944 bool IsDefinition) const {
4945 MCSymbolAttr Attr = MCSA_Invalid;
4946
4947 switch (Visibility) {
4948 default: break;
4949 case GlobalValue::HiddenVisibility:
4950 if (IsDefinition)
4951 Attr = MAI.getHiddenVisibilityAttr();
4952 else
4953 Attr = MAI.getHiddenDeclarationVisibilityAttr();
4954 break;
4955 case GlobalValue::ProtectedVisibility:
4956 Attr = MAI.getProtectedVisibilityAttr();
4957 break;
4958 }
4959
4960 if (Attr != MCSA_Invalid)
4961 OutStreamer->emitSymbolAttribute(Symbol: Sym, Attribute: Attr);
4962}
4963
4964bool AsmPrinter::shouldEmitLabelForBasicBlock(
4965 const MachineBasicBlock &MBB) const {
4966 // With `-fbasic-block-sections=`, a label is needed for every non-entry block
4967 // in the labels mode (option `=labels`) and every section beginning in the
4968 // sections mode (`=all` and `=list=`).
4969 if ((MF->getTarget().Options.BBAddrMap || MBB.isBeginSection()) &&
4970 !MBB.isEntryBlock())
4971 return true;
4972 // A label is needed for any block with at least one predecessor (when that
4973 // predecessor is not the fallthrough predecessor, or if it is an EH funclet
4974 // entry, or if a label is forced).
4975 return !MBB.pred_empty() &&
4976 (!isBlockOnlyReachableByFallthrough(MBB: &MBB) || MBB.isEHFuncletEntry() ||
4977 MBB.hasLabelMustBeEmitted());
4978}
4979
4980/// isBlockOnlyReachableByFallthough - Return true if the basic block has
4981/// exactly one predecessor and the control transfer mechanism between
4982/// the predecessor and this block is a fall-through.
4983bool AsmPrinter::
4984isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
4985 // If this is a landing pad, it isn't a fall through. If it has no preds,
4986 // then nothing falls through to it.
4987 if (MBB->isEHPad() || MBB->pred_empty())
4988 return false;
4989
4990 // If there isn't exactly one predecessor, it can't be a fall through.
4991 if (MBB->pred_size() > 1)
4992 return false;
4993
4994 // The predecessor has to be immediately before this block.
4995 MachineBasicBlock *Pred = *MBB->pred_begin();
4996 if (!Pred->isLayoutSuccessor(MBB))
4997 return false;
4998
4999 // If the block is completely empty, then it definitely does fall through.
5000 if (Pred->empty())
5001 return true;
5002
5003 // Check the terminators in the previous blocks
5004 for (const auto &MI : Pred->terminators()) {
5005 // If it is not a simple branch, we are in a table somewhere.
5006 if (!MI.isBranch() || MI.isIndirectBranch())
5007 return false;
5008
5009 // If we are the operands of one of the branches, this is not a fall
5010 // through. Note that targets with delay slots will usually bundle
5011 // terminators with the delay slot instruction.
5012 for (ConstMIBundleOperands OP(MI); OP.isValid(); ++OP) {
5013 if (OP->isJTI())
5014 return false;
5015 if (OP->isMBB() && OP->getMBB() == MBB)
5016 return false;
5017 }
5018 }
5019
5020 return true;
5021}
5022
5023GCMetadataPrinter *AsmPrinter::getOrCreateGCPrinter(GCStrategy &S) {
5024 if (!S.usesMetadata())
5025 return nullptr;
5026
5027 auto [GCPI, Inserted] = GCMetadataPrinters.try_emplace(Key: &S);
5028 if (!Inserted)
5029 return GCPI->second.get();
5030
5031 auto Name = S.getName();
5032
5033 for (const GCMetadataPrinterRegistry::entry &GCMetaPrinter :
5034 GCMetadataPrinterRegistry::entries())
5035 if (Name == GCMetaPrinter.getName()) {
5036 std::unique_ptr<GCMetadataPrinter> GMP = GCMetaPrinter.instantiate();
5037 GMP->S = &S;
5038 GCPI->second = std::move(GMP);
5039 return GCPI->second.get();
5040 }
5041
5042 report_fatal_error(reason: "no GCMetadataPrinter registered for GC: " + Twine(Name));
5043}
5044
5045void AsmPrinter::addAsmPrinterHandler(
5046 std::unique_ptr<AsmPrinterHandler> Handler) {
5047 Handlers.insert(I: Handlers.begin(), Elt: std::move(Handler));
5048 NumUserHandlers++;
5049}
5050
5051/// Pin vtables to this file.
5052AsmPrinterHandler::~AsmPrinterHandler() = default;
5053
5054void AsmPrinterHandler::markFunctionEnd() {}
5055
5056// In the binary's "xray_instr_map" section, an array of these function entries
5057// describes each instrumentation point. When XRay patches your code, the index
5058// into this table will be given to your handler as a patch point identifier.
5059void AsmPrinter::XRayFunctionEntry::emit(int Bytes, MCStreamer *Out) const {
5060 auto Kind8 = static_cast<uint8_t>(Kind);
5061 Out->emitBinaryData(Data: StringRef(reinterpret_cast<const char *>(&Kind8), 1));
5062 Out->emitBinaryData(
5063 Data: StringRef(reinterpret_cast<const char *>(&AlwaysInstrument), 1));
5064 Out->emitBinaryData(Data: StringRef(reinterpret_cast<const char *>(&Version), 1));
5065 auto Padding = (4 * Bytes) - ((2 * Bytes) + 3);
5066 assert(Padding >= 0 && "Instrumentation map entry > 4 * Word Size");
5067 Out->emitZeros(NumBytes: Padding);
5068}
5069
5070void AsmPrinter::emitXRayTable() {
5071 if (Sleds.empty())
5072 return;
5073
5074 auto PrevSection = OutStreamer->getCurrentSectionOnly();
5075 const Function &F = MF->getFunction();
5076 MCSection *InstMap = nullptr;
5077 MCSection *FnSledIndex = nullptr;
5078 const Triple &TT = TM.getTargetTriple();
5079 // Use PC-relative addresses on all targets.
5080 if (TT.isOSBinFormatELF()) {
5081 auto LinkedToSym = static_cast<const MCSymbolELF *>(CurrentFnSym);
5082 auto Flags = ELF::SHF_ALLOC | ELF::SHF_LINK_ORDER;
5083 StringRef GroupName;
5084 if (F.hasComdat()) {
5085 Flags |= ELF::SHF_GROUP;
5086 GroupName = F.getComdat()->getName();
5087 }
5088 InstMap = OutContext.getELFSection(Section: "xray_instr_map", Type: ELF::SHT_PROGBITS,
5089 Flags, EntrySize: 0, Group: GroupName, IsComdat: F.hasComdat(),
5090 UniqueID: MCSection::NonUniqueID, LinkedToSym);
5091
5092 if (TM.Options.XRayFunctionIndex)
5093 FnSledIndex = OutContext.getELFSection(
5094 Section: "xray_fn_idx", Type: ELF::SHT_PROGBITS, Flags, EntrySize: 0, Group: GroupName, IsComdat: F.hasComdat(),
5095 UniqueID: MCSection::NonUniqueID, LinkedToSym);
5096 } else if (MF->getSubtarget().getTargetTriple().isOSBinFormatMachO()) {
5097 InstMap = OutContext.getMachOSection(Segment: "__DATA", Section: "xray_instr_map",
5098 TypeAndAttributes: MachO::S_ATTR_LIVE_SUPPORT,
5099 K: SectionKind::getReadOnlyWithRel());
5100 if (TM.Options.XRayFunctionIndex)
5101 FnSledIndex = OutContext.getMachOSection(Segment: "__DATA", Section: "xray_fn_idx",
5102 TypeAndAttributes: MachO::S_ATTR_LIVE_SUPPORT,
5103 K: SectionKind::getReadOnly());
5104 } else {
5105 llvm_unreachable("Unsupported target");
5106 }
5107
5108 auto WordSizeBytes = MAI.getCodePointerSize();
5109
5110 // Now we switch to the instrumentation map section. Because this is done
5111 // per-function, we are able to create an index entry that will represent the
5112 // range of sleds associated with a function.
5113 auto &Ctx = OutContext;
5114 MCSymbol *SledsStart =
5115 OutContext.createLinkerPrivateSymbol(Name: "xray_sleds_start");
5116 OutStreamer->switchSection(Section: InstMap);
5117 OutStreamer->emitLabel(Symbol: SledsStart);
5118 for (const auto &Sled : Sleds) {
5119 MCSymbol *Dot = Ctx.createTempSymbol();
5120 OutStreamer->emitLabel(Symbol: Dot);
5121 OutStreamer->emitValueImpl(
5122 Value: MCBinaryExpr::createSub(LHS: MCSymbolRefExpr::create(Symbol: Sled.Sled, Ctx),
5123 RHS: MCSymbolRefExpr::create(Symbol: Dot, Ctx), Ctx),
5124 Size: WordSizeBytes);
5125 OutStreamer->emitValueImpl(
5126 Value: MCBinaryExpr::createSub(
5127 LHS: MCSymbolRefExpr::create(Symbol: CurrentFnBegin, Ctx),
5128 RHS: MCBinaryExpr::createAdd(LHS: MCSymbolRefExpr::create(Symbol: Dot, Ctx),
5129 RHS: MCConstantExpr::create(Value: WordSizeBytes, Ctx),
5130 Ctx),
5131 Ctx),
5132 Size: WordSizeBytes);
5133 Sled.emit(Bytes: WordSizeBytes, Out: OutStreamer.get());
5134 }
5135 MCSymbol *SledsEnd = OutContext.createTempSymbol(Name: "xray_sleds_end", AlwaysAddSuffix: true);
5136 OutStreamer->emitLabel(Symbol: SledsEnd);
5137
5138 // We then emit a single entry in the index per function. We use the symbols
5139 // that bound the instrumentation map as the range for a specific function.
5140 // Each entry contains 2 words and needs to be word-aligned.
5141 if (FnSledIndex) {
5142 OutStreamer->switchSection(Section: FnSledIndex);
5143 OutStreamer->emitValueToAlignment(Alignment: Align(WordSizeBytes));
5144 // For Mach-O, use an "l" symbol as the atom of this subsection. The label
5145 // difference uses a SUBTRACTOR external relocation which references the
5146 // symbol.
5147 MCSymbol *Dot = Ctx.createLinkerPrivateSymbol(Name: "xray_fn_idx");
5148 OutStreamer->emitLabel(Symbol: Dot);
5149 OutStreamer->emitValueImpl(
5150 Value: MCBinaryExpr::createSub(LHS: MCSymbolRefExpr::create(Symbol: SledsStart, Ctx),
5151 RHS: MCSymbolRefExpr::create(Symbol: Dot, Ctx), Ctx),
5152 Size: WordSizeBytes);
5153 OutStreamer->emitValueImpl(Value: MCConstantExpr::create(Value: Sleds.size(), Ctx),
5154 Size: WordSizeBytes);
5155 OutStreamer->switchSection(Section: PrevSection);
5156 }
5157 Sleds.clear();
5158}
5159
5160void AsmPrinter::recordSled(MCSymbol *Sled, const MachineInstr &MI,
5161 SledKind Kind, uint8_t Version) {
5162 const Function &F = MI.getMF()->getFunction();
5163 auto Attr = F.getFnAttribute(Kind: "function-instrument");
5164 bool LogArgs = F.hasFnAttribute(Kind: "xray-log-args");
5165 bool AlwaysInstrument =
5166 Attr.isStringAttribute() && Attr.getValueAsString() == "xray-always";
5167 if (Kind == SledKind::FUNCTION_ENTER && LogArgs)
5168 Kind = SledKind::LOG_ARGS_ENTER;
5169 Sleds.emplace_back(Args: XRayFunctionEntry{.Sled: Sled, .Function: CurrentFnSym, .Kind: Kind,
5170 .AlwaysInstrument: AlwaysInstrument, .Fn: &F, .Version: Version});
5171}
5172
5173void AsmPrinter::emitPatchableFunctionEntries() {
5174 const Function &F = MF->getFunction();
5175 unsigned PatchableFunctionPrefix =
5176 F.getFnAttributeAsParsedInteger(Kind: "patchable-function-prefix");
5177 unsigned PatchableFunctionEntry =
5178 F.getFnAttributeAsParsedInteger(Kind: "patchable-function-entry");
5179 if (!PatchableFunctionPrefix && !PatchableFunctionEntry)
5180 return;
5181 const unsigned PointerSize = getPointerSize();
5182 if (TM.getTargetTriple().isOSBinFormatELF()) {
5183 auto Flags = ELF::SHF_WRITE | ELF::SHF_ALLOC;
5184 const MCSymbolELF *LinkedToSym = nullptr;
5185 StringRef GroupName, SectionName;
5186
5187 if (F.hasFnAttribute(Kind: "patchable-function-entry-section"))
5188 SectionName = F.getFnAttribute(Kind: "patchable-function-entry-section")
5189 .getValueAsString();
5190 if (SectionName.empty())
5191 SectionName = "__patchable_function_entries";
5192
5193 // GNU as < 2.35 did not support section flag 'o'. GNU ld < 2.36 did not
5194 // support mixed SHF_LINK_ORDER and non-SHF_LINK_ORDER sections.
5195 if (MAI.useIntegratedAssembler() || MAI.binutilsIsAtLeast(Major: 2, Minor: 36)) {
5196 Flags |= ELF::SHF_LINK_ORDER;
5197 if (F.hasComdat()) {
5198 Flags |= ELF::SHF_GROUP;
5199 GroupName = F.getComdat()->getName();
5200 }
5201 LinkedToSym = static_cast<const MCSymbolELF *>(CurrentFnSym);
5202 }
5203 OutStreamer->switchSection(Section: OutContext.getELFSection(
5204 Section: SectionName, Type: ELF::SHT_PROGBITS, Flags, EntrySize: 0, Group: GroupName, IsComdat: F.hasComdat(),
5205 UniqueID: MCSection::NonUniqueID, LinkedToSym));
5206 emitAlignment(Alignment: Align(PointerSize));
5207 OutStreamer->emitSymbolValue(Sym: CurrentPatchableFunctionEntrySym, Size: PointerSize);
5208 }
5209}
5210
5211uint16_t AsmPrinter::getDwarfVersion() const {
5212 return OutStreamer->getContext().getDwarfVersion();
5213}
5214
5215void AsmPrinter::setDwarfVersion(uint16_t Version) {
5216 OutStreamer->getContext().setDwarfVersion(Version);
5217}
5218
5219bool AsmPrinter::isDwarf64() const {
5220 return OutStreamer->getContext().getDwarfFormat() == dwarf::DWARF64;
5221}
5222
5223unsigned int AsmPrinter::getDwarfOffsetByteSize() const {
5224 return dwarf::getDwarfOffsetByteSize(
5225 Format: OutStreamer->getContext().getDwarfFormat());
5226}
5227
5228dwarf::FormParams AsmPrinter::getDwarfFormParams() const {
5229 return {.Version: getDwarfVersion(), .AddrSize: uint8_t(MAI.getCodePointerSize()),
5230 .Format: OutStreamer->getContext().getDwarfFormat(),
5231 .DwarfUsesRelocationsAcrossSections: doesDwarfUseRelocationsAcrossSections()};
5232}
5233
5234unsigned int AsmPrinter::getUnitLengthFieldByteSize() const {
5235 return dwarf::getUnitLengthFieldByteSize(
5236 Format: OutStreamer->getContext().getDwarfFormat());
5237}
5238
5239std::tuple<const MCSymbol *, uint64_t, const MCSymbol *,
5240 codeview::JumpTableEntrySize>
5241AsmPrinter::getCodeViewJumpTableInfo(int JTI, const MachineInstr *BranchInstr,
5242 const MCSymbol *BranchLabel) const {
5243 const auto TLI = MF->getSubtarget().getTargetLowering();
5244 const auto BaseExpr =
5245 TLI->getPICJumpTableRelocBaseExpr(MF, JTI, Ctx&: MMI->getContext());
5246 const auto Base = &cast<MCSymbolRefExpr>(Val: BaseExpr)->getSymbol();
5247
5248 // By default, for the architectures that support CodeView,
5249 // EK_LabelDifference32 is implemented as an Int32 from the base address.
5250 return std::make_tuple(args: Base, args: 0, args&: BranchLabel,
5251 args: codeview::JumpTableEntrySize::Int32);
5252}
5253
5254void AsmPrinter::emitCOFFReplaceableFunctionData(Module &M) {
5255 const Triple &TT = TM.getTargetTriple();
5256 assert(TT.isOSBinFormatCOFF());
5257
5258 bool IsTargetArm64EC = TT.isWindowsArm64EC();
5259 SmallVector<char> Buf;
5260 SmallVector<MCSymbol *> FuncOverrideDefaultSymbols;
5261 bool SwitchedToDirectiveSection = false;
5262 for (const Function &F : M.functions()) {
5263 if (F.hasFnAttribute(Kind: "loader-replaceable")) {
5264 if (!SwitchedToDirectiveSection) {
5265 OutStreamer->switchSection(
5266 Section: OutContext.getObjectFileInfo()->getDrectveSection());
5267 SwitchedToDirectiveSection = true;
5268 }
5269
5270 StringRef Name = F.getName();
5271
5272 // For hybrid-patchable targets, strip the prefix so that we can mark
5273 // the real function as replaceable.
5274 if (IsTargetArm64EC && Name.ends_with(Suffix: HybridPatchableTargetSuffix)) {
5275 Name = Name.drop_back(N: HybridPatchableTargetSuffix.size());
5276 }
5277
5278 MCSymbol *FuncOverrideSymbol =
5279 MMI->getContext().getOrCreateSymbol(Name: Name + "_$fo$");
5280 OutStreamer->beginCOFFSymbolDef(Symbol: FuncOverrideSymbol);
5281 OutStreamer->emitCOFFSymbolStorageClass(StorageClass: COFF::IMAGE_SYM_CLASS_EXTERNAL);
5282 OutStreamer->emitCOFFSymbolType(Type: COFF::IMAGE_SYM_DTYPE_NULL);
5283 OutStreamer->endCOFFSymbolDef();
5284
5285 MCSymbol *FuncOverrideDefaultSymbol =
5286 MMI->getContext().getOrCreateSymbol(Name: Name + "_$fo_default$");
5287 OutStreamer->beginCOFFSymbolDef(Symbol: FuncOverrideDefaultSymbol);
5288 OutStreamer->emitCOFFSymbolStorageClass(StorageClass: COFF::IMAGE_SYM_CLASS_EXTERNAL);
5289 OutStreamer->emitCOFFSymbolType(Type: COFF::IMAGE_SYM_DTYPE_NULL);
5290 OutStreamer->endCOFFSymbolDef();
5291 FuncOverrideDefaultSymbols.push_back(Elt: FuncOverrideDefaultSymbol);
5292
5293 OutStreamer->emitBytes(Data: (Twine(" /ALTERNATENAME:") +
5294 FuncOverrideSymbol->getName() + "=" +
5295 FuncOverrideDefaultSymbol->getName())
5296 .toStringRef(Out&: Buf));
5297 Buf.clear();
5298 }
5299 }
5300
5301 if (SwitchedToDirectiveSection)
5302 OutStreamer->popSection();
5303
5304 if (FuncOverrideDefaultSymbols.empty())
5305 return;
5306
5307 // MSVC emits the symbols for the default variables pointing at the start of
5308 // the .data section, but doesn't actually allocate any space for them. LLVM
5309 // can't do this, so have all of the variables pointing at a single byte
5310 // instead.
5311 OutStreamer->switchSection(Section: OutContext.getObjectFileInfo()->getDataSection());
5312 for (MCSymbol *Symbol : FuncOverrideDefaultSymbols) {
5313 OutStreamer->emitLabel(Symbol);
5314 }
5315 OutStreamer->emitZeros(NumBytes: 1);
5316 OutStreamer->popSection();
5317}
5318
5319void AsmPrinter::emitCOFFFeatureSymbol(Module &M) {
5320 const Triple &TT = TM.getTargetTriple();
5321 assert(TT.isOSBinFormatCOFF());
5322
5323 // Emit an absolute @feat.00 symbol.
5324 MCSymbol *S = MMI->getContext().getOrCreateSymbol(Name: StringRef("@feat.00"));
5325 OutStreamer->beginCOFFSymbolDef(Symbol: S);
5326 OutStreamer->emitCOFFSymbolStorageClass(StorageClass: COFF::IMAGE_SYM_CLASS_STATIC);
5327 OutStreamer->emitCOFFSymbolType(Type: COFF::IMAGE_SYM_DTYPE_NULL);
5328 OutStreamer->endCOFFSymbolDef();
5329 int64_t Feat00Value = 0;
5330
5331 if (TT.getArch() == Triple::x86) {
5332 // According to the PE-COFF spec, the LSB of this value marks the object
5333 // for "registered SEH". This means that all SEH handler entry points
5334 // must be registered in .sxdata. Use of any unregistered handlers will
5335 // cause the process to terminate immediately. LLVM does not know how to
5336 // register any SEH handlers, so its object files should be safe.
5337 Feat00Value |= COFF::Feat00Flags::SafeSEH;
5338 }
5339
5340 if (M.getControlFlowGuardMode() == ControlFlowGuardMode::Enabled) {
5341 // Object is CFG-aware. Only set if we actually inserted the checks.
5342 Feat00Value |= COFF::Feat00Flags::GuardCF;
5343 }
5344
5345 if (M.getModuleFlag(Key: "ehcontguard")) {
5346 // Object also has EHCont.
5347 Feat00Value |= COFF::Feat00Flags::GuardEHCont;
5348 }
5349
5350 if (M.getModuleFlag(Key: "ms-kernel")) {
5351 // Object is compiled with /kernel.
5352 Feat00Value |= COFF::Feat00Flags::Kernel;
5353 }
5354
5355 OutStreamer->emitSymbolAttribute(Symbol: S, Attribute: MCSA_Global);
5356 OutStreamer->emitAssignment(
5357 Symbol: S, Value: MCConstantExpr::create(Value: Feat00Value, Ctx&: MMI->getContext()));
5358}
5359
5360namespace llvm {
5361namespace {
5362MachineFunctionAnalysisManager &getMFAM(Module &M, ModuleAnalysisManager &MAM,
5363 MachineFunction &MF) {
5364 FunctionAnalysisManager &FAM =
5365 MAM.getResult<FunctionAnalysisManagerModuleProxy>(IR&: M).getManager();
5366 MachineFunctionAnalysisManager &MFAM =
5367 FAM.getResult<MachineFunctionAnalysisManagerFunctionProxy>(
5368 IR&: MF.getFunction())
5369 .getManager();
5370 return MFAM;
5371}
5372} // anonymous namespace
5373
5374void setupModuleAsmPrinter(Module &M, ModuleAnalysisManager &MAM,
5375 AsmPrinter &AsmPrinter) {
5376 MachineModuleInfo &MMI = MAM.getResult<MachineModuleAnalysis>(IR&: M).getMMI();
5377 AsmPrinter.GetMMI = [&MMI]() { return &MMI; };
5378 AsmPrinter.MMI = &MMI;
5379 AsmPrinter.GetORE = [&MAM, &M](MachineFunction &MF) {
5380 return &getMFAM(M, MAM, MF)
5381 .getResult<MachineOptimizationRemarkEmitterAnalysis>(IR&: MF);
5382 };
5383 AsmPrinter.GetMDT = [&MAM, &M](MachineFunction &MF) {
5384 return &getMFAM(M, MAM, MF).getResult<MachineDominatorTreeAnalysis>(IR&: MF);
5385 };
5386 AsmPrinter.GetMLI = [&MAM, &M](MachineFunction &MF) {
5387 return &getMFAM(M, MAM, MF).getResult<MachineLoopAnalysis>(IR&: MF);
5388 };
5389 // TODO(boomanaiden154): Get GC working with the new pass manager.
5390 AsmPrinter.BeginGCAssembly = [](Module &M) {};
5391 AsmPrinter.FinishGCAssembly = [](Module &M) {};
5392 AsmPrinter.EmitStackMaps = [](Module &M) {};
5393 AsmPrinter.AssertDebugEHFinalized = []() {};
5394}
5395
5396void setupMachineFunctionAsmPrinter(MachineFunctionAnalysisManager &MFAM,
5397 MachineFunction &MF,
5398 AsmPrinter &AsmPrinter) {
5399 const ModuleAnalysisManagerMachineFunctionProxy::Result &MAMProxy =
5400 MFAM.getResult<ModuleAnalysisManagerMachineFunctionProxy>(IR&: MF);
5401 MachineModuleInfo &MMI =
5402 MAMProxy
5403 .getCachedResult<MachineModuleAnalysis>(IR&: *MF.getFunction().getParent())
5404 ->getMMI();
5405 AsmPrinter.GetMMI = [&MMI]() { return &MMI; };
5406 AsmPrinter.MMI = &MMI;
5407 AsmPrinter.GetORE = [&MFAM](MachineFunction &MF) {
5408 return &MFAM.getResult<MachineOptimizationRemarkEmitterAnalysis>(IR&: MF);
5409 };
5410 AsmPrinter.GetMDT = [&MFAM](MachineFunction &MF) {
5411 return &MFAM.getResult<MachineDominatorTreeAnalysis>(IR&: MF);
5412 };
5413 AsmPrinter.GetMLI = [&MFAM](MachineFunction &MF) {
5414 return &MFAM.getResult<MachineLoopAnalysis>(IR&: MF);
5415 };
5416 // TODO(boomanaiden154): Get GC working with the new pass manager.
5417 AsmPrinter.BeginGCAssembly = [](Module &M) {};
5418 AsmPrinter.FinishGCAssembly = [](Module &M) {};
5419 AsmPrinter.EmitStackMaps = [](Module &M) {};
5420 AsmPrinter.AssertDebugEHFinalized = []() {};
5421}
5422
5423AnalysisKey AsmPrinterAnalysis::Key;
5424
5425} // namespace llvm
5426