1 //===-- AsmPrinter.cpp - Common AsmPrinter code ---------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the AsmPrinter class.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/CodeGen/AsmPrinter.h"
15 #include "DwarfDebug.h"
16 #include "DwarfException.h"
17 #include "WinCodeViewLineTables.h"
18 #include "llvm/ADT/SmallString.h"
19 #include "llvm/ADT/Statistic.h"
20 #include "llvm/Analysis/ConstantFolding.h"
21 #include "llvm/CodeGen/GCMetadataPrinter.h"
22 #include "llvm/CodeGen/MachineConstantPool.h"
23 #include "llvm/CodeGen/MachineFrameInfo.h"
24 #include "llvm/CodeGen/MachineFunction.h"
25 #include "llvm/CodeGen/MachineInstrBundle.h"
26 #include "llvm/CodeGen/MachineJumpTableInfo.h"
27 #include "llvm/CodeGen/MachineLoopInfo.h"
28 #include "llvm/CodeGen/MachineModuleInfo.h"
29 #include "llvm/IR/DataLayout.h"
30 #include "llvm/IR/DebugInfo.h"
31 #include "llvm/IR/Mangler.h"
32 #include "llvm/IR/Module.h"
33 #include "llvm/IR/Operator.h"
34 #include "llvm/MC/MCAsmInfo.h"
35 #include "llvm/MC/MCContext.h"
36 #include "llvm/MC/MCExpr.h"
37 #include "llvm/MC/MCInst.h"
38 #include "llvm/MC/MCSection.h"
39 #include "llvm/MC/MCStreamer.h"
40 #include "llvm/MC/MCSymbol.h"
41 #include "llvm/Support/ErrorHandling.h"
42 #include "llvm/Support/Format.h"
43 #include "llvm/Support/MathExtras.h"
44 #include "llvm/Support/Timer.h"
45 #include "llvm/Target/TargetFrameLowering.h"
46 #include "llvm/Target/TargetInstrInfo.h"
47 #include "llvm/Target/TargetLowering.h"
48 #include "llvm/Target/TargetLoweringObjectFile.h"
49 #include "llvm/Target/TargetOptions.h"
50 #include "llvm/Target/TargetRegisterInfo.h"
51 #include "llvm/Target/TargetSubtargetInfo.h"
52 #include "llvm/Transforms/Utils/GlobalStatus.h"
55 #define DEBUG_TYPE "asm-printer"
57 static const char *const DWARFGroupName = "DWARF Emission";
58 static const char *const DbgTimerName = "Debug Info Emission";
59 static const char *const EHTimerName = "DWARF Exception Writer";
60 static const char *const CodeViewLineTablesGroupName = "CodeView Line Tables";
62 STATISTIC(EmittedInsts, "Number of machine instrs printed");
64 char AsmPrinter::ID = 0;
66 typedef DenseMap<GCStrategy*, std::unique_ptr<GCMetadataPrinter>> gcp_map_type;
67 static gcp_map_type &getGCMap(void *&P) {
69 P = new gcp_map_type();
70 return *(gcp_map_type*)P;
74 /// getGVAlignmentLog2 - Return the alignment to use for the specified global
75 /// value in log2 form. This rounds up to the preferred alignment if possible
77 static unsigned getGVAlignmentLog2(const GlobalValue *GV, const DataLayout &TD,
78 unsigned InBits = 0) {
80 if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV))
81 NumBits = TD.getPreferredAlignmentLog(GVar);
83 // If InBits is specified, round it to it.
87 // If the GV has a specified alignment, take it into account.
88 if (GV->getAlignment() == 0)
91 unsigned GVAlign = Log2_32(GV->getAlignment());
93 // If the GVAlign is larger than NumBits, or if we are required to obey
94 // NumBits because the GV has an assigned section, obey it.
95 if (GVAlign > NumBits || GV->hasSection())
100 AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
101 : MachineFunctionPass(ID),
102 TM(tm), MAI(tm.getMCAsmInfo()), MII(tm.getInstrInfo()),
103 OutContext(Streamer.getContext()),
104 OutStreamer(Streamer),
105 LastMI(nullptr), LastFn(0), Counter(~0U), SetCounter(0) {
106 DD = nullptr; MMI = nullptr; LI = nullptr; MF = nullptr;
107 CurrentFnSym = CurrentFnSymForSize = nullptr;
108 GCMetadataPrinters = nullptr;
109 VerboseAsm = Streamer.isVerboseAsm();
112 AsmPrinter::~AsmPrinter() {
113 assert(!DD && Handlers.empty() && "Debug/EH info didn't get finalized");
115 if (GCMetadataPrinters) {
116 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
119 GCMetadataPrinters = nullptr;
125 /// getFunctionNumber - Return a unique ID for the current function.
127 unsigned AsmPrinter::getFunctionNumber() const {
128 return MF->getFunctionNumber();
131 const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
132 return TM.getTargetLowering()->getObjFileLowering();
135 /// getDataLayout - Return information about data layout.
136 const DataLayout &AsmPrinter::getDataLayout() const {
137 return *TM.getDataLayout();
140 const MCSubtargetInfo &AsmPrinter::getSubtargetInfo() const {
141 return TM.getSubtarget<MCSubtargetInfo>();
144 void AsmPrinter::EmitToStreamer(MCStreamer &S, const MCInst &Inst) {
145 S.EmitInstruction(Inst, getSubtargetInfo());
148 StringRef AsmPrinter::getTargetTriple() const {
149 return TM.getTargetTriple();
152 /// getCurrentSection() - Return the current section we are emitting to.
153 const MCSection *AsmPrinter::getCurrentSection() const {
154 return OutStreamer.getCurrentSection().first;
159 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
160 AU.setPreservesAll();
161 MachineFunctionPass::getAnalysisUsage(AU);
162 AU.addRequired<MachineModuleInfo>();
163 AU.addRequired<GCModuleInfo>();
165 AU.addRequired<MachineLoopInfo>();
168 bool AsmPrinter::doInitialization(Module &M) {
169 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
170 MMI->AnalyzeModule(M);
172 // Initialize TargetLoweringObjectFile.
173 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
174 .Initialize(OutContext, TM);
176 OutStreamer.InitSections();
178 Mang = new Mangler(TM.getDataLayout());
180 // Emit the version-min deplyment target directive if needed.
182 // FIXME: If we end up with a collection of these sorts of Darwin-specific
183 // or ELF-specific things, it may make sense to have a platform helper class
184 // that will work with the target helper class. For now keep it here, as the
185 // alternative is duplicated code in each of the target asm printers that
186 // use the directive, where it would need the same conditionalization
188 Triple TT(getTargetTriple());
189 if (TT.isOSDarwin()) {
190 unsigned Major, Minor, Update;
191 TT.getOSVersion(Major, Minor, Update);
192 // If there is a version specified, Major will be non-zero.
194 OutStreamer.EmitVersionMin((TT.isMacOSX() ?
195 MCVM_OSXVersionMin : MCVM_IOSVersionMin),
196 Major, Minor, Update);
199 // Allow the target to emit any magic that it wants at the start of the file.
200 EmitStartOfAsmFile(M);
202 // Very minimal debug info. It is ignored if we emit actual debug info. If we
203 // don't, this at least helps the user find where a global came from.
204 if (MAI->hasSingleParameterDotFile()) {
206 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
209 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
210 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
212 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
213 MP->beginAssembly(*this);
215 // Emit module-level inline asm if it exists.
216 if (!M.getModuleInlineAsm().empty()) {
217 OutStreamer.AddComment("Start of file scope inline assembly");
218 OutStreamer.AddBlankLine();
219 EmitInlineAsm(M.getModuleInlineAsm()+"\n");
220 OutStreamer.AddComment("End of file scope inline assembly");
221 OutStreamer.AddBlankLine();
224 if (MAI->doesSupportDebugInformation()) {
225 if (Triple(TM.getTargetTriple()).isKnownWindowsMSVCEnvironment()) {
226 Handlers.push_back(HandlerInfo(new WinCodeViewLineTables(this),
228 CodeViewLineTablesGroupName));
230 DD = new DwarfDebug(this, &M);
231 Handlers.push_back(HandlerInfo(DD, DbgTimerName, DWARFGroupName));
235 DwarfException *DE = nullptr;
236 switch (MAI->getExceptionHandlingType()) {
237 case ExceptionHandling::None:
239 case ExceptionHandling::SjLj:
240 case ExceptionHandling::DwarfCFI:
241 DE = new DwarfCFIException(this);
243 case ExceptionHandling::ARM:
244 DE = new ARMException(this);
246 case ExceptionHandling::Win64:
247 DE = new Win64Exception(this);
251 Handlers.push_back(HandlerInfo(DE, EHTimerName, DWARFGroupName));
255 static bool canBeHidden(const GlobalValue *GV, const MCAsmInfo &MAI) {
256 GlobalValue::LinkageTypes Linkage = GV->getLinkage();
257 if (Linkage != GlobalValue::LinkOnceODRLinkage)
260 if (!MAI.hasWeakDefCanBeHiddenDirective())
263 if (GV->hasUnnamedAddr())
266 // This is only used for MachO, so right now it doesn't really matter how
267 // we handle alias. Revisit this once the MachO linker implements aliases.
268 if (isa<GlobalAlias>(GV))
271 // If it is a non constant variable, it needs to be uniqued across shared
273 if (const GlobalVariable *Var = dyn_cast<GlobalVariable>(GV)) {
274 if (!Var->isConstant())
279 if (!GlobalStatus::analyzeGlobal(GV, GS) && !GS.IsCompared)
285 void AsmPrinter::EmitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const {
286 GlobalValue::LinkageTypes Linkage = GV->getLinkage();
288 case GlobalValue::CommonLinkage:
289 case GlobalValue::LinkOnceAnyLinkage:
290 case GlobalValue::LinkOnceODRLinkage:
291 case GlobalValue::WeakAnyLinkage:
292 case GlobalValue::WeakODRLinkage:
293 if (MAI->hasWeakDefDirective()) {
295 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
297 if (!canBeHidden(GV, *MAI))
298 // .weak_definition _foo
299 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
301 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefAutoPrivate);
302 } else if (MAI->hasLinkOnceDirective()) {
304 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
305 //NOTE: linkonce is handled by the section the symbol was assigned to.
308 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
311 case GlobalValue::AppendingLinkage:
312 // FIXME: appending linkage variables should go into a section of
313 // their name or something. For now, just emit them as external.
314 case GlobalValue::ExternalLinkage:
315 // If external or appending, declare as a global symbol.
317 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
319 case GlobalValue::PrivateLinkage:
320 case GlobalValue::InternalLinkage:
322 case GlobalValue::AvailableExternallyLinkage:
323 llvm_unreachable("Should never emit this");
324 case GlobalValue::ExternalWeakLinkage:
325 llvm_unreachable("Don't know how to emit these");
327 llvm_unreachable("Unknown linkage type!");
330 void AsmPrinter::getNameWithPrefix(SmallVectorImpl<char> &Name,
331 const GlobalValue *GV) const {
332 TM.getNameWithPrefix(Name, GV, *Mang);
335 MCSymbol *AsmPrinter::getSymbol(const GlobalValue *GV) const {
336 return TM.getSymbol(GV, *Mang);
339 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
340 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
341 if (GV->hasInitializer()) {
342 // Check to see if this is a special global used by LLVM, if so, emit it.
343 if (EmitSpecialLLVMGlobal(GV))
347 GV->printAsOperand(OutStreamer.GetCommentOS(),
348 /*PrintType=*/false, GV->getParent());
349 OutStreamer.GetCommentOS() << '\n';
353 MCSymbol *GVSym = getSymbol(GV);
354 EmitVisibility(GVSym, GV->getVisibility(), !GV->isDeclaration());
356 if (!GV->hasInitializer()) // External globals require no extra code.
359 if (MAI->hasDotTypeDotSizeDirective())
360 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
362 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
364 const DataLayout *DL = TM.getDataLayout();
365 uint64_t Size = DL->getTypeAllocSize(GV->getType()->getElementType());
367 // If the alignment is specified, we *must* obey it. Overaligning a global
368 // with a specified alignment is a prompt way to break globals emitted to
369 // sections and expected to be contiguous (e.g. ObjC metadata).
370 unsigned AlignLog = getGVAlignmentLog2(GV, *DL);
372 for (const HandlerInfo &HI : Handlers) {
373 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
374 HI.Handler->setSymbolSize(GVSym, Size);
377 // Handle common and BSS local symbols (.lcomm).
378 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
379 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
380 unsigned Align = 1 << AlignLog;
382 // Handle common symbols.
383 if (GVKind.isCommon()) {
384 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
388 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
392 // Handle local BSS symbols.
393 if (MAI->hasMachoZeroFillDirective()) {
394 const MCSection *TheSection =
395 getObjFileLowering().SectionForGlobal(GV, GVKind, *Mang, TM);
396 // .zerofill __DATA, __bss, _foo, 400, 5
397 OutStreamer.EmitZerofill(TheSection, GVSym, Size, Align);
401 // Use .lcomm only if it supports user-specified alignment.
402 // Otherwise, while it would still be correct to use .lcomm in some
403 // cases (e.g. when Align == 1), the external assembler might enfore
404 // some -unknown- default alignment behavior, which could cause
405 // spurious differences between external and integrated assembler.
406 // Prefer to simply fall back to .local / .comm in this case.
407 if (MAI->getLCOMMDirectiveAlignmentType() != LCOMM::NoAlignment) {
409 OutStreamer.EmitLocalCommonSymbol(GVSym, Size, Align);
413 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
417 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
419 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
423 const MCSection *TheSection =
424 getObjFileLowering().SectionForGlobal(GV, GVKind, *Mang, TM);
426 // Handle the zerofill directive on darwin, which is a special form of BSS
428 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
429 if (Size == 0) Size = 1; // zerofill of 0 bytes is undefined.
432 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
433 // .zerofill __DATA, __common, _foo, 400, 5
434 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
438 // Handle thread local data for mach-o which requires us to output an
439 // additional structure of data and mangle the original symbol so that we
440 // can reference it later.
442 // TODO: This should become an "emit thread local global" method on TLOF.
443 // All of this macho specific stuff should be sunk down into TLOFMachO and
444 // stuff like "TLSExtraDataSection" should no longer be part of the parent
445 // TLOF class. This will also make it more obvious that stuff like
446 // MCStreamer::EmitTBSSSymbol is macho specific and only called from macho
448 if (GVKind.isThreadLocal() && MAI->hasMachoTBSSDirective()) {
449 // Emit the .tbss symbol
451 OutContext.GetOrCreateSymbol(GVSym->getName() + Twine("$tlv$init"));
453 if (GVKind.isThreadBSS()) {
454 TheSection = getObjFileLowering().getTLSBSSSection();
455 OutStreamer.EmitTBSSSymbol(TheSection, MangSym, Size, 1 << AlignLog);
456 } else if (GVKind.isThreadData()) {
457 OutStreamer.SwitchSection(TheSection);
459 EmitAlignment(AlignLog, GV);
460 OutStreamer.EmitLabel(MangSym);
462 EmitGlobalConstant(GV->getInitializer());
465 OutStreamer.AddBlankLine();
467 // Emit the variable struct for the runtime.
468 const MCSection *TLVSect
469 = getObjFileLowering().getTLSExtraDataSection();
471 OutStreamer.SwitchSection(TLVSect);
472 // Emit the linkage here.
473 EmitLinkage(GV, GVSym);
474 OutStreamer.EmitLabel(GVSym);
476 // Three pointers in size:
477 // - __tlv_bootstrap - used to make sure support exists
478 // - spare pointer, used when mapped by the runtime
479 // - pointer to mangled symbol above with initializer
480 unsigned PtrSize = DL->getPointerTypeSize(GV->getType());
481 OutStreamer.EmitSymbolValue(GetExternalSymbolSymbol("_tlv_bootstrap"),
483 OutStreamer.EmitIntValue(0, PtrSize);
484 OutStreamer.EmitSymbolValue(MangSym, PtrSize);
486 OutStreamer.AddBlankLine();
490 OutStreamer.SwitchSection(TheSection);
492 EmitLinkage(GV, GVSym);
493 EmitAlignment(AlignLog, GV);
495 OutStreamer.EmitLabel(GVSym);
497 EmitGlobalConstant(GV->getInitializer());
499 if (MAI->hasDotTypeDotSizeDirective())
501 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
503 OutStreamer.AddBlankLine();
506 /// EmitFunctionHeader - This method emits the header for the current
508 void AsmPrinter::EmitFunctionHeader() {
509 // Print out constants referenced by the function
512 // Print the 'header' of function.
513 const Function *F = MF->getFunction();
515 OutStreamer.SwitchSection(
516 getObjFileLowering().SectionForGlobal(F, *Mang, TM));
517 EmitVisibility(CurrentFnSym, F->getVisibility());
519 EmitLinkage(F, CurrentFnSym);
520 EmitAlignment(MF->getAlignment(), F);
522 if (MAI->hasDotTypeDotSizeDirective())
523 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
526 F->printAsOperand(OutStreamer.GetCommentOS(),
527 /*PrintType=*/false, F->getParent());
528 OutStreamer.GetCommentOS() << '\n';
531 // Emit the CurrentFnSym. This is a virtual function to allow targets to
532 // do their wild and crazy things as required.
533 EmitFunctionEntryLabel();
535 // If the function had address-taken blocks that got deleted, then we have
536 // references to the dangling symbols. Emit them at the start of the function
537 // so that we don't get references to undefined symbols.
538 std::vector<MCSymbol*> DeadBlockSyms;
539 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
540 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
541 OutStreamer.AddComment("Address taken block that was later removed");
542 OutStreamer.EmitLabel(DeadBlockSyms[i]);
545 // Emit pre-function debug and/or EH information.
546 for (const HandlerInfo &HI : Handlers) {
547 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
548 HI.Handler->beginFunction(MF);
551 // Emit the prefix data.
552 if (F->hasPrefixData())
553 EmitGlobalConstant(F->getPrefixData());
556 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
557 /// function. This can be overridden by targets as required to do custom stuff.
558 void AsmPrinter::EmitFunctionEntryLabel() {
559 // The function label could have already been emitted if two symbols end up
560 // conflicting due to asm renaming. Detect this and emit an error.
561 if (CurrentFnSym->isUndefined())
562 return OutStreamer.EmitLabel(CurrentFnSym);
564 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
565 "' label emitted multiple times to assembly file");
568 /// emitComments - Pretty-print comments for instructions.
569 static void emitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
570 const MachineFunction *MF = MI.getParent()->getParent();
571 const TargetMachine &TM = MF->getTarget();
573 // Check for spills and reloads
576 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
578 // We assume a single instruction only has a spill or reload, not
580 const MachineMemOperand *MMO;
581 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
582 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
583 MMO = *MI.memoperands_begin();
584 CommentOS << MMO->getSize() << "-byte Reload\n";
586 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
587 if (FrameInfo->isSpillSlotObjectIndex(FI))
588 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
589 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
590 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
591 MMO = *MI.memoperands_begin();
592 CommentOS << MMO->getSize() << "-byte Spill\n";
594 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
595 if (FrameInfo->isSpillSlotObjectIndex(FI))
596 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
599 // Check for spill-induced copies
600 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
601 CommentOS << " Reload Reuse\n";
604 /// emitImplicitDef - This method emits the specified machine instruction
605 /// that is an implicit def.
606 void AsmPrinter::emitImplicitDef(const MachineInstr *MI) const {
607 unsigned RegNo = MI->getOperand(0).getReg();
608 OutStreamer.AddComment(Twine("implicit-def: ") +
609 TM.getRegisterInfo()->getName(RegNo));
610 OutStreamer.AddBlankLine();
613 static void emitKill(const MachineInstr *MI, AsmPrinter &AP) {
614 std::string Str = "kill:";
615 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
616 const MachineOperand &Op = MI->getOperand(i);
617 assert(Op.isReg() && "KILL instruction must have only register operands");
619 Str += AP.TM.getRegisterInfo()->getName(Op.getReg());
620 Str += (Op.isDef() ? "<def>" : "<kill>");
622 AP.OutStreamer.AddComment(Str);
623 AP.OutStreamer.AddBlankLine();
626 /// emitDebugValueComment - This method handles the target-independent form
627 /// of DBG_VALUE, returning true if it was able to do so. A false return
628 /// means the target will need to handle MI in EmitInstruction.
629 static bool emitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
630 // This code handles only the 3-operand target-independent form.
631 if (MI->getNumOperands() != 3)
634 SmallString<128> Str;
635 raw_svector_ostream OS(Str);
636 OS << "DEBUG_VALUE: ";
638 DIVariable V(MI->getOperand(2).getMetadata());
639 if (V.getContext().isSubprogram()) {
640 StringRef Name = DISubprogram(V.getContext()).getDisplayName();
644 OS << V.getName() << " <- ";
646 // The second operand is only an offset if it's an immediate.
647 bool Deref = MI->getOperand(0).isReg() && MI->getOperand(1).isImm();
648 int64_t Offset = Deref ? MI->getOperand(1).getImm() : 0;
650 // Register or immediate value. Register 0 means undef.
651 if (MI->getOperand(0).isFPImm()) {
652 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
653 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
654 OS << (double)APF.convertToFloat();
655 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
656 OS << APF.convertToDouble();
658 // There is no good way to print long double. Convert a copy to
659 // double. Ah well, it's only a comment.
661 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
663 OS << "(long double) " << APF.convertToDouble();
665 } else if (MI->getOperand(0).isImm()) {
666 OS << MI->getOperand(0).getImm();
667 } else if (MI->getOperand(0).isCImm()) {
668 MI->getOperand(0).getCImm()->getValue().print(OS, false /*isSigned*/);
671 if (MI->getOperand(0).isReg()) {
672 Reg = MI->getOperand(0).getReg();
674 assert(MI->getOperand(0).isFI() && "Unknown operand type");
675 const TargetFrameLowering *TFI = AP.TM.getFrameLowering();
676 Offset += TFI->getFrameIndexReference(*AP.MF,
677 MI->getOperand(0).getIndex(), Reg);
681 // Suppress offset, it is not meaningful here.
683 // NOTE: Want this comment at start of line, don't emit with AddComment.
684 AP.OutStreamer.emitRawComment(OS.str());
689 OS << AP.TM.getRegisterInfo()->getName(Reg);
693 OS << '+' << Offset << ']';
695 // NOTE: Want this comment at start of line, don't emit with AddComment.
696 AP.OutStreamer.emitRawComment(OS.str());
700 AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() {
701 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI &&
702 MF->getFunction()->needsUnwindTableEntry())
705 if (MMI->hasDebugInfo())
711 bool AsmPrinter::needsSEHMoves() {
712 return MAI->getExceptionHandlingType() == ExceptionHandling::Win64 &&
713 MF->getFunction()->needsUnwindTableEntry();
716 void AsmPrinter::emitCFIInstruction(const MachineInstr &MI) {
717 ExceptionHandling::ExceptionsType ExceptionHandlingType =
718 MAI->getExceptionHandlingType();
719 if (ExceptionHandlingType != ExceptionHandling::DwarfCFI &&
720 ExceptionHandlingType != ExceptionHandling::ARM)
723 if (needsCFIMoves() == CFI_M_None)
726 if (MMI->getCompactUnwindEncoding() != 0)
727 OutStreamer.EmitCompactUnwindEncoding(MMI->getCompactUnwindEncoding());
729 const MachineModuleInfo &MMI = MF->getMMI();
730 const std::vector<MCCFIInstruction> &Instrs = MMI.getFrameInstructions();
731 unsigned CFIIndex = MI.getOperand(0).getCFIIndex();
732 const MCCFIInstruction &CFI = Instrs[CFIIndex];
733 emitCFIInstruction(CFI);
736 /// EmitFunctionBody - This method emits the body and trailer for a
738 void AsmPrinter::EmitFunctionBody() {
739 // Emit target-specific gunk before the function body.
740 EmitFunctionBodyStart();
742 bool ShouldPrintDebugScopes = MMI->hasDebugInfo();
744 // Print out code for the function.
745 bool HasAnyRealCode = false;
746 const MachineInstr *LastMI = nullptr;
747 for (auto &MBB : *MF) {
748 // Print a label for the basic block.
749 EmitBasicBlockStart(MBB);
750 for (auto &MI : MBB) {
753 // Print the assembly for the instruction.
754 if (!MI.isPosition() && !MI.isImplicitDef() && !MI.isKill() &&
755 !MI.isDebugValue()) {
756 HasAnyRealCode = true;
760 if (ShouldPrintDebugScopes) {
761 for (const HandlerInfo &HI : Handlers) {
762 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
763 TimePassesIsEnabled);
764 HI.Handler->beginInstruction(&MI);
769 emitComments(MI, OutStreamer.GetCommentOS());
771 switch (MI.getOpcode()) {
772 case TargetOpcode::CFI_INSTRUCTION:
773 emitCFIInstruction(MI);
776 case TargetOpcode::EH_LABEL:
777 case TargetOpcode::GC_LABEL:
778 OutStreamer.EmitLabel(MI.getOperand(0).getMCSymbol());
780 case TargetOpcode::INLINEASM:
783 case TargetOpcode::DBG_VALUE:
785 if (!emitDebugValueComment(&MI, *this))
786 EmitInstruction(&MI);
789 case TargetOpcode::IMPLICIT_DEF:
790 if (isVerbose()) emitImplicitDef(&MI);
792 case TargetOpcode::KILL:
793 if (isVerbose()) emitKill(&MI, *this);
796 EmitInstruction(&MI);
800 if (ShouldPrintDebugScopes) {
801 for (const HandlerInfo &HI : Handlers) {
802 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
803 TimePassesIsEnabled);
804 HI.Handler->endInstruction();
810 // If the last instruction was a prolog label, then we have a situation where
811 // we emitted a prolog but no function body. This results in the ending prolog
812 // label equaling the end of function label and an invalid "row" in the
813 // FDE. We need to emit a noop in this situation so that the FDE's rows are
815 bool RequiresNoop = LastMI && LastMI->isCFIInstruction();
817 // If the function is empty and the object file uses .subsections_via_symbols,
818 // then we need to emit *something* to the function body to prevent the
819 // labels from collapsing together. Just emit a noop.
820 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) || RequiresNoop) {
822 TM.getInstrInfo()->getNoopForMachoTarget(Noop);
823 if (Noop.getOpcode()) {
824 OutStreamer.AddComment("avoids zero-length function");
825 OutStreamer.EmitInstruction(Noop, getSubtargetInfo());
826 } else // Target not mc-ized yet.
827 OutStreamer.EmitRawText(StringRef("\tnop\n"));
830 const Function *F = MF->getFunction();
831 for (const auto &BB : *F) {
832 if (!BB.hasAddressTaken())
834 MCSymbol *Sym = GetBlockAddressSymbol(&BB);
835 if (Sym->isDefined())
837 OutStreamer.AddComment("Address of block that was removed by CodeGen");
838 OutStreamer.EmitLabel(Sym);
841 // Emit target-specific gunk after the function body.
842 EmitFunctionBodyEnd();
844 // If the target wants a .size directive for the size of the function, emit
846 if (MAI->hasDotTypeDotSizeDirective()) {
847 // Create a symbol for the end of function, so we can get the size as
848 // difference between the function label and the temp label.
849 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
850 OutStreamer.EmitLabel(FnEndLabel);
852 const MCExpr *SizeExp =
853 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
854 MCSymbolRefExpr::Create(CurrentFnSymForSize,
857 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
860 // Emit post-function debug and/or EH information.
861 for (const HandlerInfo &HI : Handlers) {
862 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
863 HI.Handler->endFunction(MF);
867 // Print out jump tables referenced by the function.
870 OutStreamer.AddBlankLine();
873 bool AsmPrinter::doFinalization(Module &M) {
874 // Emit global variables.
875 for (const auto &G : M.globals())
876 EmitGlobalVariable(&G);
878 // Emit visibility info for declarations
879 for (const Function &F : M) {
880 if (!F.isDeclaration())
882 GlobalValue::VisibilityTypes V = F.getVisibility();
883 if (V == GlobalValue::DefaultVisibility)
886 MCSymbol *Name = getSymbol(&F);
887 EmitVisibility(Name, V, false);
890 // Emit module flags.
891 SmallVector<Module::ModuleFlagEntry, 8> ModuleFlags;
892 M.getModuleFlagsMetadata(ModuleFlags);
893 if (!ModuleFlags.empty())
894 getObjFileLowering().emitModuleFlags(OutStreamer, ModuleFlags, *Mang, TM);
896 // Make sure we wrote out everything we need.
899 // Finalize debug and EH information.
900 for (const HandlerInfo &HI : Handlers) {
901 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
902 TimePassesIsEnabled);
903 HI.Handler->endModule();
909 // If the target wants to know about weak references, print them all.
910 if (MAI->getWeakRefDirective()) {
911 // FIXME: This is not lazy, it would be nice to only print weak references
912 // to stuff that is actually used. Note that doing so would require targets
913 // to notice uses in operands (due to constant exprs etc). This should
914 // happen with the MC stuff eventually.
916 // Print out module-level global variables here.
917 for (const auto &G : M.globals()) {
918 if (!G.hasExternalWeakLinkage())
920 OutStreamer.EmitSymbolAttribute(getSymbol(&G), MCSA_WeakReference);
923 for (const auto &F : M) {
924 if (!F.hasExternalWeakLinkage())
926 OutStreamer.EmitSymbolAttribute(getSymbol(&F), MCSA_WeakReference);
930 if (MAI->hasSetDirective()) {
931 OutStreamer.AddBlankLine();
932 for (const auto &Alias : M.aliases()) {
933 MCSymbol *Name = getSymbol(&Alias);
935 const GlobalValue *GV = Alias.getAliasee();
936 assert(!GV->isDeclaration());
937 MCSymbol *Target = getSymbol(GV);
939 if (Alias.hasExternalLinkage() || !MAI->getWeakRefDirective())
940 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
941 else if (Alias.hasWeakLinkage() || Alias.hasLinkOnceLinkage())
942 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
944 assert(Alias.hasLocalLinkage() && "Invalid alias linkage");
946 EmitVisibility(Name, Alias.getVisibility());
948 // Emit the directives as assignments aka .set:
949 OutStreamer.EmitAssignment(Name,
950 MCSymbolRefExpr::Create(Target, OutContext));
954 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
955 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
956 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
957 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(**--I))
958 MP->finishAssembly(*this);
960 // Emit llvm.ident metadata in an '.ident' directive.
963 // If we don't have any trampolines, then we don't require stack memory
964 // to be executable. Some targets have a directive to declare this.
965 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
966 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
967 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext))
968 OutStreamer.SwitchSection(S);
970 // Allow the target to emit any magic that it wants at the end of the file,
971 // after everything else has gone out.
974 delete Mang; Mang = nullptr;
977 OutStreamer.Finish();
983 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
985 // Get the function symbol.
986 CurrentFnSym = getSymbol(MF.getFunction());
987 CurrentFnSymForSize = CurrentFnSym;
990 LI = &getAnalysis<MachineLoopInfo>();
994 // SectionCPs - Keep track the alignment, constpool entries per Section.
998 SmallVector<unsigned, 4> CPEs;
999 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
1003 /// EmitConstantPool - Print to the current output stream assembly
1004 /// representations of the constants in the constant pool MCP. This is
1005 /// used to print out constants which have been "spilled to memory" by
1006 /// the code generator.
1008 void AsmPrinter::EmitConstantPool() {
1009 const MachineConstantPool *MCP = MF->getConstantPool();
1010 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
1011 if (CP.empty()) return;
1013 // Calculate sections for constant pool entries. We collect entries to go into
1014 // the same section together to reduce amount of section switch statements.
1015 SmallVector<SectionCPs, 4> CPSections;
1016 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
1017 const MachineConstantPoolEntry &CPE = CP[i];
1018 unsigned Align = CPE.getAlignment();
1021 switch (CPE.getRelocationInfo()) {
1022 default: llvm_unreachable("Unknown section kind");
1023 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
1025 Kind = SectionKind::getReadOnlyWithRelLocal();
1028 switch (TM.getDataLayout()->getTypeAllocSize(CPE.getType())) {
1029 case 4: Kind = SectionKind::getMergeableConst4(); break;
1030 case 8: Kind = SectionKind::getMergeableConst8(); break;
1031 case 16: Kind = SectionKind::getMergeableConst16();break;
1032 default: Kind = SectionKind::getMergeableConst(); break;
1036 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
1038 // The number of sections are small, just do a linear search from the
1039 // last section to the first.
1041 unsigned SecIdx = CPSections.size();
1042 while (SecIdx != 0) {
1043 if (CPSections[--SecIdx].S == S) {
1049 SecIdx = CPSections.size();
1050 CPSections.push_back(SectionCPs(S, Align));
1053 if (Align > CPSections[SecIdx].Alignment)
1054 CPSections[SecIdx].Alignment = Align;
1055 CPSections[SecIdx].CPEs.push_back(i);
1058 // Now print stuff into the calculated sections.
1059 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
1060 OutStreamer.SwitchSection(CPSections[i].S);
1061 EmitAlignment(Log2_32(CPSections[i].Alignment));
1063 unsigned Offset = 0;
1064 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
1065 unsigned CPI = CPSections[i].CPEs[j];
1066 MachineConstantPoolEntry CPE = CP[CPI];
1068 // Emit inter-object padding for alignment.
1069 unsigned AlignMask = CPE.getAlignment() - 1;
1070 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
1071 OutStreamer.EmitZeros(NewOffset - Offset);
1073 Type *Ty = CPE.getType();
1074 Offset = NewOffset + TM.getDataLayout()->getTypeAllocSize(Ty);
1075 OutStreamer.EmitLabel(GetCPISymbol(CPI));
1077 if (CPE.isMachineConstantPoolEntry())
1078 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
1080 EmitGlobalConstant(CPE.Val.ConstVal);
1085 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
1086 /// by the current function to the current output stream.
1088 void AsmPrinter::EmitJumpTableInfo() {
1089 const DataLayout *DL = MF->getTarget().getDataLayout();
1090 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1092 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
1093 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1094 if (JT.empty()) return;
1096 // Pick the directive to use to print the jump table entries, and switch to
1097 // the appropriate section.
1098 const Function *F = MF->getFunction();
1099 bool JTInDiffSection = false;
1100 if (// In PIC mode, we need to emit the jump table to the same section as the
1101 // function body itself, otherwise the label differences won't make sense.
1102 // FIXME: Need a better predicate for this: what about custom entries?
1103 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
1104 // We should also do if the section name is NULL or function is declared
1105 // in discardable section
1106 // FIXME: this isn't the right predicate, should be based on the MCSection
1107 // for the function.
1108 F->isWeakForLinker()) {
1109 OutStreamer.SwitchSection(
1110 getObjFileLowering().SectionForGlobal(F, *Mang, TM));
1112 // Otherwise, drop it in the readonly section.
1113 const MCSection *ReadOnlySection =
1114 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
1115 OutStreamer.SwitchSection(ReadOnlySection);
1116 JTInDiffSection = true;
1119 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getDataLayout())));
1121 // Jump tables in code sections are marked with a data_region directive
1122 // where that's supported.
1123 if (!JTInDiffSection)
1124 OutStreamer.EmitDataRegion(MCDR_DataRegionJT32);
1126 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
1127 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1129 // If this jump table was deleted, ignore it.
1130 if (JTBBs.empty()) continue;
1132 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
1133 // .set directive for each unique entry. This reduces the number of
1134 // relocations the assembler will generate for the jump table.
1135 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
1136 MAI->hasSetDirective()) {
1137 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
1138 const TargetLowering *TLI = TM.getTargetLowering();
1139 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
1140 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
1141 const MachineBasicBlock *MBB = JTBBs[ii];
1142 if (!EmittedSets.insert(MBB)) continue;
1144 // .set LJTSet, LBB32-base
1146 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1147 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
1148 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
1152 // On some targets (e.g. Darwin) we want to emit two consecutive labels
1153 // before each jump table. The first label is never referenced, but tells
1154 // the assembler and linker the extents of the jump table object. The
1155 // second label is actually referenced by the code.
1156 if (JTInDiffSection && DL->hasLinkerPrivateGlobalPrefix())
1157 // FIXME: This doesn't have to have any specific name, just any randomly
1158 // named and numbered 'l' label would work. Simplify GetJTISymbol.
1159 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
1161 OutStreamer.EmitLabel(GetJTISymbol(JTI));
1163 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
1164 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
1166 if (!JTInDiffSection)
1167 OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
1170 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
1172 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
1173 const MachineBasicBlock *MBB,
1174 unsigned UID) const {
1175 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block");
1176 const MCExpr *Value = nullptr;
1177 switch (MJTI->getEntryKind()) {
1178 case MachineJumpTableInfo::EK_Inline:
1179 llvm_unreachable("Cannot emit EK_Inline jump table entry");
1180 case MachineJumpTableInfo::EK_Custom32:
1181 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
1184 case MachineJumpTableInfo::EK_BlockAddress:
1185 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
1187 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1189 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
1190 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
1191 // with a relocation as gp-relative, e.g.:
1193 MCSymbol *MBBSym = MBB->getSymbol();
1194 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1198 case MachineJumpTableInfo::EK_GPRel64BlockAddress: {
1199 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded
1200 // with a relocation as gp-relative, e.g.:
1202 MCSymbol *MBBSym = MBB->getSymbol();
1203 OutStreamer.EmitGPRel64Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1207 case MachineJumpTableInfo::EK_LabelDifference32: {
1208 // EK_LabelDifference32 - Each entry is the address of the block minus
1209 // the address of the jump table. This is used for PIC jump tables where
1210 // gprel32 is not supported. e.g.:
1211 // .word LBB123 - LJTI1_2
1212 // If the .set directive is supported, this is emitted as:
1213 // .set L4_5_set_123, LBB123 - LJTI1_2
1214 // .word L4_5_set_123
1216 // If we have emitted set directives for the jump table entries, print
1217 // them rather than the entries themselves. If we're emitting PIC, then
1218 // emit the table entries as differences between two text section labels.
1219 if (MAI->hasSetDirective()) {
1220 // If we used .set, reference the .set's symbol.
1221 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
1225 // Otherwise, use the difference as the jump table entry.
1226 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1227 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
1228 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
1233 assert(Value && "Unknown entry kind!");
1235 unsigned EntrySize = MJTI->getEntrySize(*TM.getDataLayout());
1236 OutStreamer.EmitValue(Value, EntrySize);
1240 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
1241 /// special global used by LLVM. If so, emit it and return true, otherwise
1242 /// do nothing and return false.
1243 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
1244 if (GV->getName() == "llvm.used") {
1245 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
1246 EmitLLVMUsedList(cast<ConstantArray>(GV->getInitializer()));
1250 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
1251 if (GV->getSection() == "llvm.metadata" ||
1252 GV->hasAvailableExternallyLinkage())
1255 if (!GV->hasAppendingLinkage()) return false;
1257 assert(GV->hasInitializer() && "Not a special LLVM global!");
1259 if (GV->getName() == "llvm.global_ctors") {
1260 EmitXXStructorList(GV->getInitializer(), /* isCtor */ true);
1262 if (TM.getRelocationModel() == Reloc::Static &&
1263 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1264 StringRef Sym(".constructors_used");
1265 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1271 if (GV->getName() == "llvm.global_dtors") {
1272 EmitXXStructorList(GV->getInitializer(), /* isCtor */ false);
1274 if (TM.getRelocationModel() == Reloc::Static &&
1275 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1276 StringRef Sym(".destructors_used");
1277 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1286 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1287 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1288 /// is true, as being used with this directive.
1289 void AsmPrinter::EmitLLVMUsedList(const ConstantArray *InitList) {
1290 // Should be an array of 'i8*'.
1291 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1292 const GlobalValue *GV =
1293 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1295 OutStreamer.EmitSymbolAttribute(getSymbol(GV), MCSA_NoDeadStrip);
1301 Structor() : Priority(0), Func(nullptr), ComdatKey(nullptr) {}
1303 llvm::Constant *Func;
1304 llvm::GlobalValue *ComdatKey;
1308 /// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
1310 void AsmPrinter::EmitXXStructorList(const Constant *List, bool isCtor) {
1311 // Should be an array of '{ int, void ()* }' structs. The first value is the
1313 if (!isa<ConstantArray>(List)) return;
1315 // Sanity check the structors list.
1316 const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1317 if (!InitList) return; // Not an array!
1318 StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType());
1319 // FIXME: Only allow the 3-field form in LLVM 4.0.
1320 if (!ETy || ETy->getNumElements() < 2 || ETy->getNumElements() > 3)
1321 return; // Not an array of two or three elements!
1322 if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) ||
1323 !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr).
1324 if (ETy->getNumElements() == 3 && !isa<PointerType>(ETy->getTypeAtIndex(2U)))
1325 return; // Not (int, ptr, ptr).
1327 // Gather the structors in a form that's convenient for sorting by priority.
1328 SmallVector<Structor, 8> Structors;
1329 for (Value *O : InitList->operands()) {
1330 ConstantStruct *CS = dyn_cast<ConstantStruct>(O);
1331 if (!CS) continue; // Malformed.
1332 if (CS->getOperand(1)->isNullValue())
1333 break; // Found a null terminator, skip the rest.
1334 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
1335 if (!Priority) continue; // Malformed.
1336 Structors.push_back(Structor());
1337 Structor &S = Structors.back();
1338 S.Priority = Priority->getLimitedValue(65535);
1339 S.Func = CS->getOperand(1);
1340 if (ETy->getNumElements() == 3 && !CS->getOperand(2)->isNullValue())
1341 S.ComdatKey = dyn_cast<GlobalValue>(CS->getOperand(2)->stripPointerCasts());
1344 // Emit the function pointers in the target-specific order
1345 const DataLayout *DL = TM.getDataLayout();
1346 unsigned Align = Log2_32(DL->getPointerPrefAlignment());
1347 std::stable_sort(Structors.begin(), Structors.end(),
1348 [](const Structor &L,
1349 const Structor &R) { return L.Priority < R.Priority; });
1350 for (Structor &S : Structors) {
1351 const TargetLoweringObjectFile &Obj = getObjFileLowering();
1352 const MCSymbol *KeySym = nullptr;
1353 const MCSection *KeySec = nullptr;
1355 KeySym = getSymbol(S.ComdatKey);
1356 KeySec = getObjFileLowering().SectionForGlobal(S.ComdatKey, *Mang, TM);
1358 const MCSection *OutputSection =
1359 (isCtor ? Obj.getStaticCtorSection(S.Priority, KeySym, KeySec)
1360 : Obj.getStaticDtorSection(S.Priority, KeySym, KeySec));
1361 OutStreamer.SwitchSection(OutputSection);
1362 if (OutStreamer.getCurrentSection() != OutStreamer.getPreviousSection())
1363 EmitAlignment(Align);
1364 EmitXXStructor(S.Func);
1368 void AsmPrinter::EmitModuleIdents(Module &M) {
1369 if (!MAI->hasIdentDirective())
1372 if (const NamedMDNode *NMD = M.getNamedMetadata("llvm.ident")) {
1373 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
1374 const MDNode *N = NMD->getOperand(i);
1375 assert(N->getNumOperands() == 1 &&
1376 "llvm.ident metadata entry can have only one operand");
1377 const MDString *S = cast<MDString>(N->getOperand(0));
1378 OutStreamer.EmitIdent(S->getString());
1383 //===--------------------------------------------------------------------===//
1384 // Emission and print routines
1387 /// EmitInt8 - Emit a byte directive and value.
1389 void AsmPrinter::EmitInt8(int Value) const {
1390 OutStreamer.EmitIntValue(Value, 1);
1393 /// EmitInt16 - Emit a short directive and value.
1395 void AsmPrinter::EmitInt16(int Value) const {
1396 OutStreamer.EmitIntValue(Value, 2);
1399 /// EmitInt32 - Emit a long directive and value.
1401 void AsmPrinter::EmitInt32(int Value) const {
1402 OutStreamer.EmitIntValue(Value, 4);
1405 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
1406 /// in bytes of the directive is specified by Size and Hi/Lo specify the
1407 /// labels. This implicitly uses .set if it is available.
1408 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1409 unsigned Size) const {
1410 // Get the Hi-Lo expression.
1411 const MCExpr *Diff =
1412 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1413 MCSymbolRefExpr::Create(Lo, OutContext),
1416 if (!MAI->hasSetDirective()) {
1417 OutStreamer.EmitValue(Diff, Size);
1421 // Otherwise, emit with .set (aka assignment).
1422 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1423 OutStreamer.EmitAssignment(SetLabel, Diff);
1424 OutStreamer.EmitSymbolValue(SetLabel, Size);
1427 /// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo"
1428 /// where the size in bytes of the directive is specified by Size and Hi/Lo
1429 /// specify the labels. This implicitly uses .set if it is available.
1430 void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset,
1432 unsigned Size) const {
1434 // Emit Hi+Offset - Lo
1435 // Get the Hi+Offset expression.
1436 const MCExpr *Plus =
1437 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext),
1438 MCConstantExpr::Create(Offset, OutContext),
1441 // Get the Hi+Offset-Lo expression.
1442 const MCExpr *Diff =
1443 MCBinaryExpr::CreateSub(Plus,
1444 MCSymbolRefExpr::Create(Lo, OutContext),
1447 if (!MAI->hasSetDirective())
1448 OutStreamer.EmitValue(Diff, Size);
1450 // Otherwise, emit with .set (aka assignment).
1451 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1452 OutStreamer.EmitAssignment(SetLabel, Diff);
1453 OutStreamer.EmitSymbolValue(SetLabel, Size);
1457 /// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
1458 /// where the size in bytes of the directive is specified by Size and Label
1459 /// specifies the label. This implicitly uses .set if it is available.
1460 void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset,
1462 bool IsSectionRelative) const {
1463 if (MAI->needsDwarfSectionOffsetDirective() && IsSectionRelative) {
1464 OutStreamer.EmitCOFFSecRel32(Label);
1468 // Emit Label+Offset (or just Label if Offset is zero)
1469 const MCExpr *Expr = MCSymbolRefExpr::Create(Label, OutContext);
1471 Expr = MCBinaryExpr::CreateAdd(
1472 Expr, MCConstantExpr::Create(Offset, OutContext), OutContext);
1474 OutStreamer.EmitValue(Expr, Size);
1477 //===----------------------------------------------------------------------===//
1479 // EmitAlignment - Emit an alignment directive to the specified power of
1480 // two boundary. For example, if you pass in 3 here, you will get an 8
1481 // byte alignment. If a global value is specified, and if that global has
1482 // an explicit alignment requested, it will override the alignment request
1483 // if required for correctness.
1485 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalObject *GV) const {
1486 if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getDataLayout(), NumBits);
1488 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.
1490 if (getCurrentSection()->getKind().isText())
1491 OutStreamer.EmitCodeAlignment(1 << NumBits);
1493 OutStreamer.EmitValueToAlignment(1 << NumBits);
1496 //===----------------------------------------------------------------------===//
1497 // Constant emission.
1498 //===----------------------------------------------------------------------===//
1500 /// lowerConstant - Lower the specified LLVM Constant to an MCExpr.
1502 static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP) {
1503 MCContext &Ctx = AP.OutContext;
1505 if (CV->isNullValue() || isa<UndefValue>(CV))
1506 return MCConstantExpr::Create(0, Ctx);
1508 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1509 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1511 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1512 return MCSymbolRefExpr::Create(AP.getSymbol(GV), Ctx);
1514 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1515 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1517 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1519 llvm_unreachable("Unknown constant value to lower!");
1522 if (const MCExpr *RelocExpr =
1523 AP.getObjFileLowering().getExecutableRelativeSymbol(CE, *AP.Mang,
1527 switch (CE->getOpcode()) {
1529 // If the code isn't optimized, there may be outstanding folding
1530 // opportunities. Attempt to fold the expression using DataLayout as a
1531 // last resort before giving up.
1533 ConstantFoldConstantExpression(CE, AP.TM.getDataLayout()))
1535 return lowerConstant(C, AP);
1537 // Otherwise report the problem to the user.
1540 raw_string_ostream OS(S);
1541 OS << "Unsupported expression in static initializer: ";
1542 CE->printAsOperand(OS, /*PrintType=*/false,
1543 !AP.MF ? nullptr : AP.MF->getFunction()->getParent());
1544 report_fatal_error(OS.str());
1546 case Instruction::GetElementPtr: {
1547 const DataLayout &DL = *AP.TM.getDataLayout();
1548 // Generate a symbolic expression for the byte address
1549 APInt OffsetAI(DL.getPointerTypeSizeInBits(CE->getType()), 0);
1550 cast<GEPOperator>(CE)->accumulateConstantOffset(DL, OffsetAI);
1552 const MCExpr *Base = lowerConstant(CE->getOperand(0), AP);
1556 int64_t Offset = OffsetAI.getSExtValue();
1557 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1561 case Instruction::Trunc:
1562 // We emit the value and depend on the assembler to truncate the generated
1563 // expression properly. This is important for differences between
1564 // blockaddress labels. Since the two labels are in the same function, it
1565 // is reasonable to treat their delta as a 32-bit value.
1567 case Instruction::BitCast:
1568 return lowerConstant(CE->getOperand(0), AP);
1570 case Instruction::IntToPtr: {
1571 const DataLayout &DL = *AP.TM.getDataLayout();
1572 // Handle casts to pointers by changing them into casts to the appropriate
1573 // integer type. This promotes constant folding and simplifies this code.
1574 Constant *Op = CE->getOperand(0);
1575 Op = ConstantExpr::getIntegerCast(Op, DL.getIntPtrType(CV->getType()),
1577 return lowerConstant(Op, AP);
1580 case Instruction::PtrToInt: {
1581 const DataLayout &DL = *AP.TM.getDataLayout();
1582 // Support only foldable casts to/from pointers that can be eliminated by
1583 // changing the pointer to the appropriately sized integer type.
1584 Constant *Op = CE->getOperand(0);
1585 Type *Ty = CE->getType();
1587 const MCExpr *OpExpr = lowerConstant(Op, AP);
1589 // We can emit the pointer value into this slot if the slot is an
1590 // integer slot equal to the size of the pointer.
1591 if (DL.getTypeAllocSize(Ty) == DL.getTypeAllocSize(Op->getType()))
1594 // Otherwise the pointer is smaller than the resultant integer, mask off
1595 // the high bits so we are sure to get a proper truncation if the input is
1597 unsigned InBits = DL.getTypeAllocSizeInBits(Op->getType());
1598 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1599 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1602 // The MC library also has a right-shift operator, but it isn't consistently
1603 // signed or unsigned between different targets.
1604 case Instruction::Add:
1605 case Instruction::Sub:
1606 case Instruction::Mul:
1607 case Instruction::SDiv:
1608 case Instruction::SRem:
1609 case Instruction::Shl:
1610 case Instruction::And:
1611 case Instruction::Or:
1612 case Instruction::Xor: {
1613 const MCExpr *LHS = lowerConstant(CE->getOperand(0), AP);
1614 const MCExpr *RHS = lowerConstant(CE->getOperand(1), AP);
1615 switch (CE->getOpcode()) {
1616 default: llvm_unreachable("Unknown binary operator constant cast expr");
1617 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1618 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1619 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1620 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1621 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1622 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1623 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1624 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1625 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1631 static void emitGlobalConstantImpl(const Constant *C, AsmPrinter &AP);
1633 /// isRepeatedByteSequence - Determine whether the given value is
1634 /// composed of a repeated sequence of identical bytes and return the
1635 /// byte value. If it is not a repeated sequence, return -1.
1636 static int isRepeatedByteSequence(const ConstantDataSequential *V) {
1637 StringRef Data = V->getRawDataValues();
1638 assert(!Data.empty() && "Empty aggregates should be CAZ node");
1640 for (unsigned i = 1, e = Data.size(); i != e; ++i)
1641 if (Data[i] != C) return -1;
1642 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1.
1646 /// isRepeatedByteSequence - Determine whether the given value is
1647 /// composed of a repeated sequence of identical bytes and return the
1648 /// byte value. If it is not a repeated sequence, return -1.
1649 static int isRepeatedByteSequence(const Value *V, TargetMachine &TM) {
1651 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
1652 if (CI->getBitWidth() > 64) return -1;
1654 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(V->getType());
1655 uint64_t Value = CI->getZExtValue();
1657 // Make sure the constant is at least 8 bits long and has a power
1658 // of 2 bit width. This guarantees the constant bit width is
1659 // always a multiple of 8 bits, avoiding issues with padding out
1660 // to Size and other such corner cases.
1661 if (CI->getBitWidth() < 8 || !isPowerOf2_64(CI->getBitWidth())) return -1;
1663 uint8_t Byte = static_cast<uint8_t>(Value);
1665 for (unsigned i = 1; i < Size; ++i) {
1667 if (static_cast<uint8_t>(Value) != Byte) return -1;
1671 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) {
1672 // Make sure all array elements are sequences of the same repeated
1674 assert(CA->getNumOperands() != 0 && "Should be a CAZ");
1675 int Byte = isRepeatedByteSequence(CA->getOperand(0), TM);
1676 if (Byte == -1) return -1;
1678 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i) {
1679 int ThisByte = isRepeatedByteSequence(CA->getOperand(i), TM);
1680 if (ThisByte == -1) return -1;
1681 if (Byte != ThisByte) return -1;
1686 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V))
1687 return isRepeatedByteSequence(CDS);
1692 static void emitGlobalConstantDataSequential(const ConstantDataSequential *CDS,
1695 // See if we can aggregate this into a .fill, if so, emit it as such.
1696 int Value = isRepeatedByteSequence(CDS, AP.TM);
1698 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CDS->getType());
1699 // Don't emit a 1-byte object as a .fill.
1701 return AP.OutStreamer.EmitFill(Bytes, Value);
1704 // If this can be emitted with .ascii/.asciz, emit it as such.
1705 if (CDS->isString())
1706 return AP.OutStreamer.EmitBytes(CDS->getAsString());
1708 // Otherwise, emit the values in successive locations.
1709 unsigned ElementByteSize = CDS->getElementByteSize();
1710 if (isa<IntegerType>(CDS->getElementType())) {
1711 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1713 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1714 CDS->getElementAsInteger(i));
1715 AP.OutStreamer.EmitIntValue(CDS->getElementAsInteger(i),
1718 } else if (ElementByteSize == 4) {
1719 // FP Constants are printed as integer constants to avoid losing
1721 assert(CDS->getElementType()->isFloatTy());
1722 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1728 F = CDS->getElementAsFloat(i);
1730 AP.OutStreamer.GetCommentOS() << "float " << F << '\n';
1731 AP.OutStreamer.EmitIntValue(I, 4);
1734 assert(CDS->getElementType()->isDoubleTy());
1735 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1741 F = CDS->getElementAsDouble(i);
1743 AP.OutStreamer.GetCommentOS() << "double " << F << '\n';
1744 AP.OutStreamer.EmitIntValue(I, 8);
1748 const DataLayout &DL = *AP.TM.getDataLayout();
1749 unsigned Size = DL.getTypeAllocSize(CDS->getType());
1750 unsigned EmittedSize = DL.getTypeAllocSize(CDS->getType()->getElementType()) *
1751 CDS->getNumElements();
1752 if (unsigned Padding = Size - EmittedSize)
1753 AP.OutStreamer.EmitZeros(Padding);
1757 static void emitGlobalConstantArray(const ConstantArray *CA, AsmPrinter &AP) {
1758 // See if we can aggregate some values. Make sure it can be
1759 // represented as a series of bytes of the constant value.
1760 int Value = isRepeatedByteSequence(CA, AP.TM);
1763 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CA->getType());
1764 AP.OutStreamer.EmitFill(Bytes, Value);
1767 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1768 emitGlobalConstantImpl(CA->getOperand(i), AP);
1772 static void emitGlobalConstantVector(const ConstantVector *CV, AsmPrinter &AP) {
1773 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1774 emitGlobalConstantImpl(CV->getOperand(i), AP);
1776 const DataLayout &DL = *AP.TM.getDataLayout();
1777 unsigned Size = DL.getTypeAllocSize(CV->getType());
1778 unsigned EmittedSize = DL.getTypeAllocSize(CV->getType()->getElementType()) *
1779 CV->getType()->getNumElements();
1780 if (unsigned Padding = Size - EmittedSize)
1781 AP.OutStreamer.EmitZeros(Padding);
1784 static void emitGlobalConstantStruct(const ConstantStruct *CS, AsmPrinter &AP) {
1785 // Print the fields in successive locations. Pad to align if needed!
1786 const DataLayout *DL = AP.TM.getDataLayout();
1787 unsigned Size = DL->getTypeAllocSize(CS->getType());
1788 const StructLayout *Layout = DL->getStructLayout(CS->getType());
1789 uint64_t SizeSoFar = 0;
1790 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1791 const Constant *Field = CS->getOperand(i);
1793 // Check if padding is needed and insert one or more 0s.
1794 uint64_t FieldSize = DL->getTypeAllocSize(Field->getType());
1795 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1796 - Layout->getElementOffset(i)) - FieldSize;
1797 SizeSoFar += FieldSize + PadSize;
1799 // Now print the actual field value.
1800 emitGlobalConstantImpl(Field, AP);
1802 // Insert padding - this may include padding to increase the size of the
1803 // current field up to the ABI size (if the struct is not packed) as well
1804 // as padding to ensure that the next field starts at the right offset.
1805 AP.OutStreamer.EmitZeros(PadSize);
1807 assert(SizeSoFar == Layout->getSizeInBytes() &&
1808 "Layout of constant struct may be incorrect!");
1811 static void emitGlobalConstantFP(const ConstantFP *CFP, AsmPrinter &AP) {
1812 APInt API = CFP->getValueAPF().bitcastToAPInt();
1814 // First print a comment with what we think the original floating-point value
1815 // should have been.
1816 if (AP.isVerbose()) {
1817 SmallString<8> StrVal;
1818 CFP->getValueAPF().toString(StrVal);
1820 CFP->getType()->print(AP.OutStreamer.GetCommentOS());
1821 AP.OutStreamer.GetCommentOS() << ' ' << StrVal << '\n';
1824 // Now iterate through the APInt chunks, emitting them in endian-correct
1825 // order, possibly with a smaller chunk at beginning/end (e.g. for x87 80-bit
1827 unsigned NumBytes = API.getBitWidth() / 8;
1828 unsigned TrailingBytes = NumBytes % sizeof(uint64_t);
1829 const uint64_t *p = API.getRawData();
1831 // PPC's long double has odd notions of endianness compared to how LLVM
1832 // handles it: p[0] goes first for *big* endian on PPC.
1833 if (AP.TM.getDataLayout()->isBigEndian() != CFP->getType()->isPPC_FP128Ty()) {
1834 int Chunk = API.getNumWords() - 1;
1837 AP.OutStreamer.EmitIntValue(p[Chunk--], TrailingBytes);
1839 for (; Chunk >= 0; --Chunk)
1840 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1843 for (Chunk = 0; Chunk < NumBytes / sizeof(uint64_t); ++Chunk)
1844 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1847 AP.OutStreamer.EmitIntValue(p[Chunk], TrailingBytes);
1850 // Emit the tail padding for the long double.
1851 const DataLayout &DL = *AP.TM.getDataLayout();
1852 AP.OutStreamer.EmitZeros(DL.getTypeAllocSize(CFP->getType()) -
1853 DL.getTypeStoreSize(CFP->getType()));
1856 static void emitGlobalConstantLargeInt(const ConstantInt *CI, AsmPrinter &AP) {
1857 const DataLayout *DL = AP.TM.getDataLayout();
1858 unsigned BitWidth = CI->getBitWidth();
1860 // Copy the value as we may massage the layout for constants whose bit width
1861 // is not a multiple of 64-bits.
1862 APInt Realigned(CI->getValue());
1863 uint64_t ExtraBits = 0;
1864 unsigned ExtraBitsSize = BitWidth & 63;
1866 if (ExtraBitsSize) {
1867 // The bit width of the data is not a multiple of 64-bits.
1868 // The extra bits are expected to be at the end of the chunk of the memory.
1870 // * Nothing to be done, just record the extra bits to emit.
1872 // * Record the extra bits to emit.
1873 // * Realign the raw data to emit the chunks of 64-bits.
1874 if (DL->isBigEndian()) {
1875 // Basically the structure of the raw data is a chunk of 64-bits cells:
1876 // 0 1 BitWidth / 64
1877 // [chunk1][chunk2] ... [chunkN].
1878 // The most significant chunk is chunkN and it should be emitted first.
1879 // However, due to the alignment issue chunkN contains useless bits.
1880 // Realign the chunks so that they contain only useless information:
1881 // ExtraBits 0 1 (BitWidth / 64) - 1
1882 // chu[nk1 chu][nk2 chu] ... [nkN-1 chunkN]
1883 ExtraBits = Realigned.getRawData()[0] &
1884 (((uint64_t)-1) >> (64 - ExtraBitsSize));
1885 Realigned = Realigned.lshr(ExtraBitsSize);
1887 ExtraBits = Realigned.getRawData()[BitWidth / 64];
1890 // We don't expect assemblers to support integer data directives
1891 // for more than 64 bits, so we emit the data in at most 64-bit
1892 // quantities at a time.
1893 const uint64_t *RawData = Realigned.getRawData();
1894 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1895 uint64_t Val = DL->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1896 AP.OutStreamer.EmitIntValue(Val, 8);
1899 if (ExtraBitsSize) {
1900 // Emit the extra bits after the 64-bits chunks.
1902 // Emit a directive that fills the expected size.
1903 uint64_t Size = AP.TM.getDataLayout()->getTypeAllocSize(CI->getType());
1904 Size -= (BitWidth / 64) * 8;
1905 assert(Size && Size * 8 >= ExtraBitsSize &&
1906 (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize)))
1907 == ExtraBits && "Directive too small for extra bits.");
1908 AP.OutStreamer.EmitIntValue(ExtraBits, Size);
1912 static void emitGlobalConstantImpl(const Constant *CV, AsmPrinter &AP) {
1913 const DataLayout *DL = AP.TM.getDataLayout();
1914 uint64_t Size = DL->getTypeAllocSize(CV->getType());
1915 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV))
1916 return AP.OutStreamer.EmitZeros(Size);
1918 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1925 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1926 CI->getZExtValue());
1927 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size);
1930 emitGlobalConstantLargeInt(CI, AP);
1935 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1936 return emitGlobalConstantFP(CFP, AP);
1938 if (isa<ConstantPointerNull>(CV)) {
1939 AP.OutStreamer.EmitIntValue(0, Size);
1943 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV))
1944 return emitGlobalConstantDataSequential(CDS, AP);
1946 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1947 return emitGlobalConstantArray(CVA, AP);
1949 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1950 return emitGlobalConstantStruct(CVS, AP);
1952 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
1953 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
1955 if (CE->getOpcode() == Instruction::BitCast)
1956 return emitGlobalConstantImpl(CE->getOperand(0), AP);
1959 // If the constant expression's size is greater than 64-bits, then we have
1960 // to emit the value in chunks. Try to constant fold the value and emit it
1962 Constant *New = ConstantFoldConstantExpression(CE, DL);
1963 if (New && New != CE)
1964 return emitGlobalConstantImpl(New, AP);
1968 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1969 return emitGlobalConstantVector(V, AP);
1971 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1972 // thread the streamer with EmitValue.
1973 AP.OutStreamer.EmitValue(lowerConstant(CV, AP), Size);
1976 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1977 void AsmPrinter::EmitGlobalConstant(const Constant *CV) {
1978 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(CV->getType());
1980 emitGlobalConstantImpl(CV, *this);
1981 else if (MAI->hasSubsectionsViaSymbols()) {
1982 // If the global has zero size, emit a single byte so that two labels don't
1983 // look like they are at the same location.
1984 OutStreamer.EmitIntValue(0, 1);
1988 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1989 // Target doesn't support this yet!
1990 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1993 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1995 OS << '+' << Offset;
1996 else if (Offset < 0)
2000 //===----------------------------------------------------------------------===//
2001 // Symbol Lowering Routines.
2002 //===----------------------------------------------------------------------===//
2004 /// GetTempSymbol - Return the MCSymbol corresponding to the assembler
2005 /// temporary label with the specified stem and unique ID.
2006 MCSymbol *AsmPrinter::GetTempSymbol(Twine Name, unsigned ID) const {
2007 const DataLayout *DL = TM.getDataLayout();
2008 return OutContext.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix()) +
2012 /// GetTempSymbol - Return an assembler temporary label with the specified
2014 MCSymbol *AsmPrinter::GetTempSymbol(Twine Name) const {
2015 const DataLayout *DL = TM.getDataLayout();
2016 return OutContext.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix())+
2021 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
2022 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
2025 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
2026 return MMI->getAddrLabelSymbol(BB);
2029 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
2030 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
2031 const DataLayout *DL = TM.getDataLayout();
2032 return OutContext.GetOrCreateSymbol
2033 (Twine(DL->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
2034 + "_" + Twine(CPID));
2037 /// GetJTISymbol - Return the symbol for the specified jump table entry.
2038 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
2039 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
2042 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
2043 /// FIXME: privatize to AsmPrinter.
2044 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
2045 const DataLayout *DL = TM.getDataLayout();
2046 return OutContext.GetOrCreateSymbol
2047 (Twine(DL->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
2048 Twine(UID) + "_set_" + Twine(MBBID));
2051 MCSymbol *AsmPrinter::getSymbolWithGlobalValueBase(const GlobalValue *GV,
2052 StringRef Suffix) const {
2053 return getObjFileLowering().getSymbolWithGlobalValueBase(GV, Suffix, *Mang,
2057 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
2059 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
2060 SmallString<60> NameStr;
2061 Mang->getNameWithPrefix(NameStr, Sym);
2062 return OutContext.GetOrCreateSymbol(NameStr.str());
2067 /// PrintParentLoopComment - Print comments about parent loops of this one.
2068 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2069 unsigned FunctionNumber) {
2071 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
2072 OS.indent(Loop->getLoopDepth()*2)
2073 << "Parent Loop BB" << FunctionNumber << "_"
2074 << Loop->getHeader()->getNumber()
2075 << " Depth=" << Loop->getLoopDepth() << '\n';
2079 /// PrintChildLoopComment - Print comments about child loops within
2080 /// the loop for this basic block, with nesting.
2081 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2082 unsigned FunctionNumber) {
2083 // Add child loop information
2084 for (const MachineLoop *CL : *Loop) {
2085 OS.indent(CL->getLoopDepth()*2)
2086 << "Child Loop BB" << FunctionNumber << "_"
2087 << CL->getHeader()->getNumber() << " Depth " << CL->getLoopDepth()
2089 PrintChildLoopComment(OS, CL, FunctionNumber);
2093 /// emitBasicBlockLoopComments - Pretty-print comments for basic blocks.
2094 static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
2095 const MachineLoopInfo *LI,
2096 const AsmPrinter &AP) {
2097 // Add loop depth information
2098 const MachineLoop *Loop = LI->getLoopFor(&MBB);
2101 MachineBasicBlock *Header = Loop->getHeader();
2102 assert(Header && "No header for loop");
2104 // If this block is not a loop header, just print out what is the loop header
2106 if (Header != &MBB) {
2107 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
2108 Twine(AP.getFunctionNumber())+"_" +
2109 Twine(Loop->getHeader()->getNumber())+
2110 " Depth="+Twine(Loop->getLoopDepth()));
2114 // Otherwise, it is a loop header. Print out information about child and
2116 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
2118 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
2121 OS.indent(Loop->getLoopDepth()*2-2);
2126 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
2128 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
2132 /// EmitBasicBlockStart - This method prints the label for the specified
2133 /// MachineBasicBlock, an alignment (if present) and a comment describing
2134 /// it if appropriate.
2135 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock &MBB) const {
2136 // Emit an alignment directive for this block, if needed.
2137 if (unsigned Align = MBB.getAlignment())
2138 EmitAlignment(Align);
2140 // If the block has its address taken, emit any labels that were used to
2141 // reference the block. It is possible that there is more than one label
2142 // here, because multiple LLVM BB's may have been RAUW'd to this block after
2143 // the references were generated.
2144 if (MBB.hasAddressTaken()) {
2145 const BasicBlock *BB = MBB.getBasicBlock();
2147 OutStreamer.AddComment("Block address taken");
2149 std::vector<MCSymbol*> Symbols = MMI->getAddrLabelSymbolToEmit(BB);
2150 for (auto *Sym : Symbols)
2151 OutStreamer.EmitLabel(Sym);
2154 // Print some verbose block comments.
2156 if (const BasicBlock *BB = MBB.getBasicBlock())
2158 OutStreamer.AddComment("%" + BB->getName());
2159 emitBasicBlockLoopComments(MBB, LI, *this);
2162 // Print the main label for the block.
2163 if (MBB.pred_empty() || isBlockOnlyReachableByFallthrough(&MBB)) {
2165 // NOTE: Want this comment at start of line, don't emit with AddComment.
2166 OutStreamer.emitRawComment(" BB#" + Twine(MBB.getNumber()) + ":", false);
2169 OutStreamer.EmitLabel(MBB.getSymbol());
2173 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility,
2174 bool IsDefinition) const {
2175 MCSymbolAttr Attr = MCSA_Invalid;
2177 switch (Visibility) {
2179 case GlobalValue::HiddenVisibility:
2181 Attr = MAI->getHiddenVisibilityAttr();
2183 Attr = MAI->getHiddenDeclarationVisibilityAttr();
2185 case GlobalValue::ProtectedVisibility:
2186 Attr = MAI->getProtectedVisibilityAttr();
2190 if (Attr != MCSA_Invalid)
2191 OutStreamer.EmitSymbolAttribute(Sym, Attr);
2194 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
2195 /// exactly one predecessor and the control transfer mechanism between
2196 /// the predecessor and this block is a fall-through.
2198 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
2199 // If this is a landing pad, it isn't a fall through. If it has no preds,
2200 // then nothing falls through to it.
2201 if (MBB->isLandingPad() || MBB->pred_empty())
2204 // If there isn't exactly one predecessor, it can't be a fall through.
2205 if (MBB->pred_size() > 1)
2208 // The predecessor has to be immediately before this block.
2209 MachineBasicBlock *Pred = *MBB->pred_begin();
2210 if (!Pred->isLayoutSuccessor(MBB))
2213 // If the block is completely empty, then it definitely does fall through.
2217 // Check the terminators in the previous blocks
2218 for (const auto &MI : Pred->terminators()) {
2219 // If it is not a simple branch, we are in a table somewhere.
2220 if (!MI.isBranch() || MI.isIndirectBranch())
2223 // If we are the operands of one of the branches, this is not a fall
2224 // through. Note that targets with delay slots will usually bundle
2225 // terminators with the delay slot instruction.
2226 for (ConstMIBundleOperands OP(&MI); OP.isValid(); ++OP) {
2229 if (OP->isMBB() && OP->getMBB() == MBB)
2239 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy &S) {
2240 if (!S.usesMetadata())
2243 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
2244 gcp_map_type::iterator GCPI = GCMap.find(&S);
2245 if (GCPI != GCMap.end())
2246 return GCPI->second.get();
2248 const char *Name = S.getName().c_str();
2250 for (GCMetadataPrinterRegistry::iterator
2251 I = GCMetadataPrinterRegistry::begin(),
2252 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
2253 if (strcmp(Name, I->getName()) == 0) {
2254 std::unique_ptr<GCMetadataPrinter> GMP = I->instantiate();
2256 auto IterBool = GCMap.insert(std::make_pair(&S, std::move(GMP)));
2257 return IterBool.first->second.get();
2260 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));
2263 /// Pin vtable to this file.
2264 AsmPrinterHandler::~AsmPrinterHandler() {}