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.getAliasedGlobal();
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 const MCExpr *Expr = MCSymbolRefExpr::Create(Target, OutContext);
950 if (uint64_t Offset = Alias.calculateOffset(*TM.getDataLayout()))
951 Expr = MCBinaryExpr::CreateAdd(Expr,
952 MCConstantExpr::Create(Offset, OutContext), OutContext);
953 OutStreamer.EmitAssignment(Name, Expr);
957 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
958 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
959 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
960 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(**--I))
961 MP->finishAssembly(*this);
963 // Emit llvm.ident metadata in an '.ident' directive.
966 // If we don't have any trampolines, then we don't require stack memory
967 // to be executable. Some targets have a directive to declare this.
968 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
969 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
970 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext))
971 OutStreamer.SwitchSection(S);
973 // Allow the target to emit any magic that it wants at the end of the file,
974 // after everything else has gone out.
977 delete Mang; Mang = nullptr;
980 OutStreamer.Finish();
986 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
988 // Get the function symbol.
989 CurrentFnSym = getSymbol(MF.getFunction());
990 CurrentFnSymForSize = CurrentFnSym;
993 LI = &getAnalysis<MachineLoopInfo>();
997 // SectionCPs - Keep track the alignment, constpool entries per Section.
1001 SmallVector<unsigned, 4> CPEs;
1002 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
1006 /// EmitConstantPool - Print to the current output stream assembly
1007 /// representations of the constants in the constant pool MCP. This is
1008 /// used to print out constants which have been "spilled to memory" by
1009 /// the code generator.
1011 void AsmPrinter::EmitConstantPool() {
1012 const MachineConstantPool *MCP = MF->getConstantPool();
1013 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
1014 if (CP.empty()) return;
1016 // Calculate sections for constant pool entries. We collect entries to go into
1017 // the same section together to reduce amount of section switch statements.
1018 SmallVector<SectionCPs, 4> CPSections;
1019 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
1020 const MachineConstantPoolEntry &CPE = CP[i];
1021 unsigned Align = CPE.getAlignment();
1024 switch (CPE.getRelocationInfo()) {
1025 default: llvm_unreachable("Unknown section kind");
1026 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
1028 Kind = SectionKind::getReadOnlyWithRelLocal();
1031 switch (TM.getDataLayout()->getTypeAllocSize(CPE.getType())) {
1032 case 4: Kind = SectionKind::getMergeableConst4(); break;
1033 case 8: Kind = SectionKind::getMergeableConst8(); break;
1034 case 16: Kind = SectionKind::getMergeableConst16();break;
1035 default: Kind = SectionKind::getMergeableConst(); break;
1039 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
1041 // The number of sections are small, just do a linear search from the
1042 // last section to the first.
1044 unsigned SecIdx = CPSections.size();
1045 while (SecIdx != 0) {
1046 if (CPSections[--SecIdx].S == S) {
1052 SecIdx = CPSections.size();
1053 CPSections.push_back(SectionCPs(S, Align));
1056 if (Align > CPSections[SecIdx].Alignment)
1057 CPSections[SecIdx].Alignment = Align;
1058 CPSections[SecIdx].CPEs.push_back(i);
1061 // Now print stuff into the calculated sections.
1062 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
1063 OutStreamer.SwitchSection(CPSections[i].S);
1064 EmitAlignment(Log2_32(CPSections[i].Alignment));
1066 unsigned Offset = 0;
1067 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
1068 unsigned CPI = CPSections[i].CPEs[j];
1069 MachineConstantPoolEntry CPE = CP[CPI];
1071 // Emit inter-object padding for alignment.
1072 unsigned AlignMask = CPE.getAlignment() - 1;
1073 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
1074 OutStreamer.EmitZeros(NewOffset - Offset);
1076 Type *Ty = CPE.getType();
1077 Offset = NewOffset + TM.getDataLayout()->getTypeAllocSize(Ty);
1078 OutStreamer.EmitLabel(GetCPISymbol(CPI));
1080 if (CPE.isMachineConstantPoolEntry())
1081 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
1083 EmitGlobalConstant(CPE.Val.ConstVal);
1088 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
1089 /// by the current function to the current output stream.
1091 void AsmPrinter::EmitJumpTableInfo() {
1092 const DataLayout *DL = MF->getTarget().getDataLayout();
1093 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1095 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
1096 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1097 if (JT.empty()) return;
1099 // Pick the directive to use to print the jump table entries, and switch to
1100 // the appropriate section.
1101 const Function *F = MF->getFunction();
1102 bool JTInDiffSection = false;
1103 if (// In PIC mode, we need to emit the jump table to the same section as the
1104 // function body itself, otherwise the label differences won't make sense.
1105 // FIXME: Need a better predicate for this: what about custom entries?
1106 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
1107 // We should also do if the section name is NULL or function is declared
1108 // in discardable section
1109 // FIXME: this isn't the right predicate, should be based on the MCSection
1110 // for the function.
1111 F->isWeakForLinker()) {
1112 OutStreamer.SwitchSection(
1113 getObjFileLowering().SectionForGlobal(F, *Mang, TM));
1115 // Otherwise, drop it in the readonly section.
1116 const MCSection *ReadOnlySection =
1117 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
1118 OutStreamer.SwitchSection(ReadOnlySection);
1119 JTInDiffSection = true;
1122 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getDataLayout())));
1124 // Jump tables in code sections are marked with a data_region directive
1125 // where that's supported.
1126 if (!JTInDiffSection)
1127 OutStreamer.EmitDataRegion(MCDR_DataRegionJT32);
1129 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
1130 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1132 // If this jump table was deleted, ignore it.
1133 if (JTBBs.empty()) continue;
1135 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
1136 // .set directive for each unique entry. This reduces the number of
1137 // relocations the assembler will generate for the jump table.
1138 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
1139 MAI->hasSetDirective()) {
1140 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
1141 const TargetLowering *TLI = TM.getTargetLowering();
1142 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
1143 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
1144 const MachineBasicBlock *MBB = JTBBs[ii];
1145 if (!EmittedSets.insert(MBB)) continue;
1147 // .set LJTSet, LBB32-base
1149 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1150 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
1151 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
1155 // On some targets (e.g. Darwin) we want to emit two consecutive labels
1156 // before each jump table. The first label is never referenced, but tells
1157 // the assembler and linker the extents of the jump table object. The
1158 // second label is actually referenced by the code.
1159 if (JTInDiffSection && DL->hasLinkerPrivateGlobalPrefix())
1160 // FIXME: This doesn't have to have any specific name, just any randomly
1161 // named and numbered 'l' label would work. Simplify GetJTISymbol.
1162 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
1164 OutStreamer.EmitLabel(GetJTISymbol(JTI));
1166 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
1167 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
1169 if (!JTInDiffSection)
1170 OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
1173 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
1175 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
1176 const MachineBasicBlock *MBB,
1177 unsigned UID) const {
1178 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block");
1179 const MCExpr *Value = nullptr;
1180 switch (MJTI->getEntryKind()) {
1181 case MachineJumpTableInfo::EK_Inline:
1182 llvm_unreachable("Cannot emit EK_Inline jump table entry");
1183 case MachineJumpTableInfo::EK_Custom32:
1184 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
1187 case MachineJumpTableInfo::EK_BlockAddress:
1188 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
1190 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1192 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
1193 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
1194 // with a relocation as gp-relative, e.g.:
1196 MCSymbol *MBBSym = MBB->getSymbol();
1197 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1201 case MachineJumpTableInfo::EK_GPRel64BlockAddress: {
1202 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded
1203 // with a relocation as gp-relative, e.g.:
1205 MCSymbol *MBBSym = MBB->getSymbol();
1206 OutStreamer.EmitGPRel64Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1210 case MachineJumpTableInfo::EK_LabelDifference32: {
1211 // EK_LabelDifference32 - Each entry is the address of the block minus
1212 // the address of the jump table. This is used for PIC jump tables where
1213 // gprel32 is not supported. e.g.:
1214 // .word LBB123 - LJTI1_2
1215 // If the .set directive is supported, this is emitted as:
1216 // .set L4_5_set_123, LBB123 - LJTI1_2
1217 // .word L4_5_set_123
1219 // If we have emitted set directives for the jump table entries, print
1220 // them rather than the entries themselves. If we're emitting PIC, then
1221 // emit the table entries as differences between two text section labels.
1222 if (MAI->hasSetDirective()) {
1223 // If we used .set, reference the .set's symbol.
1224 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
1228 // Otherwise, use the difference as the jump table entry.
1229 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1230 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
1231 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
1236 assert(Value && "Unknown entry kind!");
1238 unsigned EntrySize = MJTI->getEntrySize(*TM.getDataLayout());
1239 OutStreamer.EmitValue(Value, EntrySize);
1243 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
1244 /// special global used by LLVM. If so, emit it and return true, otherwise
1245 /// do nothing and return false.
1246 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
1247 if (GV->getName() == "llvm.used") {
1248 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
1249 EmitLLVMUsedList(cast<ConstantArray>(GV->getInitializer()));
1253 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
1254 if (GV->getSection() == "llvm.metadata" ||
1255 GV->hasAvailableExternallyLinkage())
1258 if (!GV->hasAppendingLinkage()) return false;
1260 assert(GV->hasInitializer() && "Not a special LLVM global!");
1262 if (GV->getName() == "llvm.global_ctors") {
1263 EmitXXStructorList(GV->getInitializer(), /* isCtor */ true);
1265 if (TM.getRelocationModel() == Reloc::Static &&
1266 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1267 StringRef Sym(".constructors_used");
1268 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1274 if (GV->getName() == "llvm.global_dtors") {
1275 EmitXXStructorList(GV->getInitializer(), /* isCtor */ false);
1277 if (TM.getRelocationModel() == Reloc::Static &&
1278 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1279 StringRef Sym(".destructors_used");
1280 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1289 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1290 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1291 /// is true, as being used with this directive.
1292 void AsmPrinter::EmitLLVMUsedList(const ConstantArray *InitList) {
1293 // Should be an array of 'i8*'.
1294 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1295 const GlobalValue *GV =
1296 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1298 OutStreamer.EmitSymbolAttribute(getSymbol(GV), MCSA_NoDeadStrip);
1302 /// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
1304 void AsmPrinter::EmitXXStructorList(const Constant *List, bool isCtor) {
1305 // Should be an array of '{ int, void ()* }' structs. The first value is the
1307 if (!isa<ConstantArray>(List)) return;
1309 // Sanity check the structors list.
1310 const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1311 if (!InitList) return; // Not an array!
1312 StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType());
1313 if (!ETy || ETy->getNumElements() != 2) return; // Not an array of pairs!
1314 if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) ||
1315 !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr).
1317 // Gather the structors in a form that's convenient for sorting by priority.
1318 typedef std::pair<unsigned, Constant *> Structor;
1319 SmallVector<Structor, 8> Structors;
1320 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1321 ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i));
1322 if (!CS) continue; // Malformed.
1323 if (CS->getOperand(1)->isNullValue())
1324 break; // Found a null terminator, skip the rest.
1325 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
1326 if (!Priority) continue; // Malformed.
1327 Structors.push_back(std::make_pair(Priority->getLimitedValue(65535),
1328 CS->getOperand(1)));
1331 // Emit the function pointers in the target-specific order
1332 const DataLayout *DL = TM.getDataLayout();
1333 unsigned Align = Log2_32(DL->getPointerPrefAlignment());
1334 std::stable_sort(Structors.begin(), Structors.end(), less_first());
1335 for (unsigned i = 0, e = Structors.size(); i != e; ++i) {
1336 const MCSection *OutputSection =
1338 getObjFileLowering().getStaticCtorSection(Structors[i].first) :
1339 getObjFileLowering().getStaticDtorSection(Structors[i].first));
1340 OutStreamer.SwitchSection(OutputSection);
1341 if (OutStreamer.getCurrentSection() != OutStreamer.getPreviousSection())
1342 EmitAlignment(Align);
1343 EmitXXStructor(Structors[i].second);
1347 void AsmPrinter::EmitModuleIdents(Module &M) {
1348 if (!MAI->hasIdentDirective())
1351 if (const NamedMDNode *NMD = M.getNamedMetadata("llvm.ident")) {
1352 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
1353 const MDNode *N = NMD->getOperand(i);
1354 assert(N->getNumOperands() == 1 &&
1355 "llvm.ident metadata entry can have only one operand");
1356 const MDString *S = cast<MDString>(N->getOperand(0));
1357 OutStreamer.EmitIdent(S->getString());
1362 //===--------------------------------------------------------------------===//
1363 // Emission and print routines
1366 /// EmitInt8 - Emit a byte directive and value.
1368 void AsmPrinter::EmitInt8(int Value) const {
1369 OutStreamer.EmitIntValue(Value, 1);
1372 /// EmitInt16 - Emit a short directive and value.
1374 void AsmPrinter::EmitInt16(int Value) const {
1375 OutStreamer.EmitIntValue(Value, 2);
1378 /// EmitInt32 - Emit a long directive and value.
1380 void AsmPrinter::EmitInt32(int Value) const {
1381 OutStreamer.EmitIntValue(Value, 4);
1384 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
1385 /// in bytes of the directive is specified by Size and Hi/Lo specify the
1386 /// labels. This implicitly uses .set if it is available.
1387 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1388 unsigned Size) const {
1389 // Get the Hi-Lo expression.
1390 const MCExpr *Diff =
1391 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1392 MCSymbolRefExpr::Create(Lo, OutContext),
1395 if (!MAI->hasSetDirective()) {
1396 OutStreamer.EmitValue(Diff, Size);
1400 // Otherwise, emit with .set (aka assignment).
1401 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1402 OutStreamer.EmitAssignment(SetLabel, Diff);
1403 OutStreamer.EmitSymbolValue(SetLabel, Size);
1406 /// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo"
1407 /// where the size in bytes of the directive is specified by Size and Hi/Lo
1408 /// specify the labels. This implicitly uses .set if it is available.
1409 void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset,
1411 unsigned Size) const {
1413 // Emit Hi+Offset - Lo
1414 // Get the Hi+Offset expression.
1415 const MCExpr *Plus =
1416 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext),
1417 MCConstantExpr::Create(Offset, OutContext),
1420 // Get the Hi+Offset-Lo expression.
1421 const MCExpr *Diff =
1422 MCBinaryExpr::CreateSub(Plus,
1423 MCSymbolRefExpr::Create(Lo, OutContext),
1426 if (!MAI->hasSetDirective())
1427 OutStreamer.EmitValue(Diff, Size);
1429 // Otherwise, emit with .set (aka assignment).
1430 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1431 OutStreamer.EmitAssignment(SetLabel, Diff);
1432 OutStreamer.EmitSymbolValue(SetLabel, Size);
1436 /// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
1437 /// where the size in bytes of the directive is specified by Size and Label
1438 /// specifies the label. This implicitly uses .set if it is available.
1439 void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset,
1441 bool IsSectionRelative) const {
1442 if (MAI->needsDwarfSectionOffsetDirective() && IsSectionRelative) {
1443 OutStreamer.EmitCOFFSecRel32(Label);
1447 // Emit Label+Offset (or just Label if Offset is zero)
1448 const MCExpr *Expr = MCSymbolRefExpr::Create(Label, OutContext);
1450 Expr = MCBinaryExpr::CreateAdd(
1451 Expr, MCConstantExpr::Create(Offset, OutContext), OutContext);
1453 OutStreamer.EmitValue(Expr, Size);
1456 //===----------------------------------------------------------------------===//
1458 // EmitAlignment - Emit an alignment directive to the specified power of
1459 // two boundary. For example, if you pass in 3 here, you will get an 8
1460 // byte alignment. If a global value is specified, and if that global has
1461 // an explicit alignment requested, it will override the alignment request
1462 // if required for correctness.
1464 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalObject *GV) const {
1465 if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getDataLayout(), NumBits);
1467 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.
1469 if (getCurrentSection()->getKind().isText())
1470 OutStreamer.EmitCodeAlignment(1 << NumBits);
1472 OutStreamer.EmitValueToAlignment(1 << NumBits);
1475 //===----------------------------------------------------------------------===//
1476 // Constant emission.
1477 //===----------------------------------------------------------------------===//
1479 /// lowerConstant - Lower the specified LLVM Constant to an MCExpr.
1481 static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP) {
1482 MCContext &Ctx = AP.OutContext;
1484 if (CV->isNullValue() || isa<UndefValue>(CV))
1485 return MCConstantExpr::Create(0, Ctx);
1487 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1488 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1490 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1491 return MCSymbolRefExpr::Create(AP.getSymbol(GV), Ctx);
1493 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1494 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1496 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1498 llvm_unreachable("Unknown constant value to lower!");
1501 if (const MCExpr *RelocExpr =
1502 AP.getObjFileLowering().getExecutableRelativeSymbol(CE, *AP.Mang,
1506 switch (CE->getOpcode()) {
1508 // If the code isn't optimized, there may be outstanding folding
1509 // opportunities. Attempt to fold the expression using DataLayout as a
1510 // last resort before giving up.
1512 ConstantFoldConstantExpression(CE, AP.TM.getDataLayout()))
1514 return lowerConstant(C, AP);
1516 // Otherwise report the problem to the user.
1519 raw_string_ostream OS(S);
1520 OS << "Unsupported expression in static initializer: ";
1521 CE->printAsOperand(OS, /*PrintType=*/false,
1522 !AP.MF ? nullptr : AP.MF->getFunction()->getParent());
1523 report_fatal_error(OS.str());
1525 case Instruction::GetElementPtr: {
1526 const DataLayout &DL = *AP.TM.getDataLayout();
1527 // Generate a symbolic expression for the byte address
1528 APInt OffsetAI(DL.getPointerTypeSizeInBits(CE->getType()), 0);
1529 cast<GEPOperator>(CE)->accumulateConstantOffset(DL, OffsetAI);
1531 const MCExpr *Base = lowerConstant(CE->getOperand(0), AP);
1535 int64_t Offset = OffsetAI.getSExtValue();
1536 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1540 case Instruction::Trunc:
1541 // We emit the value and depend on the assembler to truncate the generated
1542 // expression properly. This is important for differences between
1543 // blockaddress labels. Since the two labels are in the same function, it
1544 // is reasonable to treat their delta as a 32-bit value.
1546 case Instruction::BitCast:
1547 return lowerConstant(CE->getOperand(0), AP);
1549 case Instruction::IntToPtr: {
1550 const DataLayout &DL = *AP.TM.getDataLayout();
1551 // Handle casts to pointers by changing them into casts to the appropriate
1552 // integer type. This promotes constant folding and simplifies this code.
1553 Constant *Op = CE->getOperand(0);
1554 Op = ConstantExpr::getIntegerCast(Op, DL.getIntPtrType(CV->getType()),
1556 return lowerConstant(Op, AP);
1559 case Instruction::PtrToInt: {
1560 const DataLayout &DL = *AP.TM.getDataLayout();
1561 // Support only foldable casts to/from pointers that can be eliminated by
1562 // changing the pointer to the appropriately sized integer type.
1563 Constant *Op = CE->getOperand(0);
1564 Type *Ty = CE->getType();
1566 const MCExpr *OpExpr = lowerConstant(Op, AP);
1568 // We can emit the pointer value into this slot if the slot is an
1569 // integer slot equal to the size of the pointer.
1570 if (DL.getTypeAllocSize(Ty) == DL.getTypeAllocSize(Op->getType()))
1573 // Otherwise the pointer is smaller than the resultant integer, mask off
1574 // the high bits so we are sure to get a proper truncation if the input is
1576 unsigned InBits = DL.getTypeAllocSizeInBits(Op->getType());
1577 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1578 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1581 // The MC library also has a right-shift operator, but it isn't consistently
1582 // signed or unsigned between different targets.
1583 case Instruction::Add:
1584 case Instruction::Sub:
1585 case Instruction::Mul:
1586 case Instruction::SDiv:
1587 case Instruction::SRem:
1588 case Instruction::Shl:
1589 case Instruction::And:
1590 case Instruction::Or:
1591 case Instruction::Xor: {
1592 const MCExpr *LHS = lowerConstant(CE->getOperand(0), AP);
1593 const MCExpr *RHS = lowerConstant(CE->getOperand(1), AP);
1594 switch (CE->getOpcode()) {
1595 default: llvm_unreachable("Unknown binary operator constant cast expr");
1596 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1597 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1598 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1599 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1600 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1601 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1602 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1603 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1604 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1610 static void emitGlobalConstantImpl(const Constant *C, AsmPrinter &AP);
1612 /// isRepeatedByteSequence - Determine whether the given value is
1613 /// composed of a repeated sequence of identical bytes and return the
1614 /// byte value. If it is not a repeated sequence, return -1.
1615 static int isRepeatedByteSequence(const ConstantDataSequential *V) {
1616 StringRef Data = V->getRawDataValues();
1617 assert(!Data.empty() && "Empty aggregates should be CAZ node");
1619 for (unsigned i = 1, e = Data.size(); i != e; ++i)
1620 if (Data[i] != C) return -1;
1621 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1.
1625 /// isRepeatedByteSequence - Determine whether the given value is
1626 /// composed of a repeated sequence of identical bytes and return the
1627 /// byte value. If it is not a repeated sequence, return -1.
1628 static int isRepeatedByteSequence(const Value *V, TargetMachine &TM) {
1630 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
1631 if (CI->getBitWidth() > 64) return -1;
1633 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(V->getType());
1634 uint64_t Value = CI->getZExtValue();
1636 // Make sure the constant is at least 8 bits long and has a power
1637 // of 2 bit width. This guarantees the constant bit width is
1638 // always a multiple of 8 bits, avoiding issues with padding out
1639 // to Size and other such corner cases.
1640 if (CI->getBitWidth() < 8 || !isPowerOf2_64(CI->getBitWidth())) return -1;
1642 uint8_t Byte = static_cast<uint8_t>(Value);
1644 for (unsigned i = 1; i < Size; ++i) {
1646 if (static_cast<uint8_t>(Value) != Byte) return -1;
1650 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) {
1651 // Make sure all array elements are sequences of the same repeated
1653 assert(CA->getNumOperands() != 0 && "Should be a CAZ");
1654 int Byte = isRepeatedByteSequence(CA->getOperand(0), TM);
1655 if (Byte == -1) return -1;
1657 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i) {
1658 int ThisByte = isRepeatedByteSequence(CA->getOperand(i), TM);
1659 if (ThisByte == -1) return -1;
1660 if (Byte != ThisByte) return -1;
1665 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V))
1666 return isRepeatedByteSequence(CDS);
1671 static void emitGlobalConstantDataSequential(const ConstantDataSequential *CDS,
1674 // See if we can aggregate this into a .fill, if so, emit it as such.
1675 int Value = isRepeatedByteSequence(CDS, AP.TM);
1677 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CDS->getType());
1678 // Don't emit a 1-byte object as a .fill.
1680 return AP.OutStreamer.EmitFill(Bytes, Value);
1683 // If this can be emitted with .ascii/.asciz, emit it as such.
1684 if (CDS->isString())
1685 return AP.OutStreamer.EmitBytes(CDS->getAsString());
1687 // Otherwise, emit the values in successive locations.
1688 unsigned ElementByteSize = CDS->getElementByteSize();
1689 if (isa<IntegerType>(CDS->getElementType())) {
1690 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1692 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1693 CDS->getElementAsInteger(i));
1694 AP.OutStreamer.EmitIntValue(CDS->getElementAsInteger(i),
1697 } else if (ElementByteSize == 4) {
1698 // FP Constants are printed as integer constants to avoid losing
1700 assert(CDS->getElementType()->isFloatTy());
1701 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1707 F = CDS->getElementAsFloat(i);
1709 AP.OutStreamer.GetCommentOS() << "float " << F << '\n';
1710 AP.OutStreamer.EmitIntValue(I, 4);
1713 assert(CDS->getElementType()->isDoubleTy());
1714 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1720 F = CDS->getElementAsDouble(i);
1722 AP.OutStreamer.GetCommentOS() << "double " << F << '\n';
1723 AP.OutStreamer.EmitIntValue(I, 8);
1727 const DataLayout &DL = *AP.TM.getDataLayout();
1728 unsigned Size = DL.getTypeAllocSize(CDS->getType());
1729 unsigned EmittedSize = DL.getTypeAllocSize(CDS->getType()->getElementType()) *
1730 CDS->getNumElements();
1731 if (unsigned Padding = Size - EmittedSize)
1732 AP.OutStreamer.EmitZeros(Padding);
1736 static void emitGlobalConstantArray(const ConstantArray *CA, AsmPrinter &AP) {
1737 // See if we can aggregate some values. Make sure it can be
1738 // represented as a series of bytes of the constant value.
1739 int Value = isRepeatedByteSequence(CA, AP.TM);
1742 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CA->getType());
1743 AP.OutStreamer.EmitFill(Bytes, Value);
1746 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1747 emitGlobalConstantImpl(CA->getOperand(i), AP);
1751 static void emitGlobalConstantVector(const ConstantVector *CV, AsmPrinter &AP) {
1752 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1753 emitGlobalConstantImpl(CV->getOperand(i), AP);
1755 const DataLayout &DL = *AP.TM.getDataLayout();
1756 unsigned Size = DL.getTypeAllocSize(CV->getType());
1757 unsigned EmittedSize = DL.getTypeAllocSize(CV->getType()->getElementType()) *
1758 CV->getType()->getNumElements();
1759 if (unsigned Padding = Size - EmittedSize)
1760 AP.OutStreamer.EmitZeros(Padding);
1763 static void emitGlobalConstantStruct(const ConstantStruct *CS, AsmPrinter &AP) {
1764 // Print the fields in successive locations. Pad to align if needed!
1765 const DataLayout *DL = AP.TM.getDataLayout();
1766 unsigned Size = DL->getTypeAllocSize(CS->getType());
1767 const StructLayout *Layout = DL->getStructLayout(CS->getType());
1768 uint64_t SizeSoFar = 0;
1769 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1770 const Constant *Field = CS->getOperand(i);
1772 // Check if padding is needed and insert one or more 0s.
1773 uint64_t FieldSize = DL->getTypeAllocSize(Field->getType());
1774 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1775 - Layout->getElementOffset(i)) - FieldSize;
1776 SizeSoFar += FieldSize + PadSize;
1778 // Now print the actual field value.
1779 emitGlobalConstantImpl(Field, AP);
1781 // Insert padding - this may include padding to increase the size of the
1782 // current field up to the ABI size (if the struct is not packed) as well
1783 // as padding to ensure that the next field starts at the right offset.
1784 AP.OutStreamer.EmitZeros(PadSize);
1786 assert(SizeSoFar == Layout->getSizeInBytes() &&
1787 "Layout of constant struct may be incorrect!");
1790 static void emitGlobalConstantFP(const ConstantFP *CFP, AsmPrinter &AP) {
1791 APInt API = CFP->getValueAPF().bitcastToAPInt();
1793 // First print a comment with what we think the original floating-point value
1794 // should have been.
1795 if (AP.isVerbose()) {
1796 SmallString<8> StrVal;
1797 CFP->getValueAPF().toString(StrVal);
1799 CFP->getType()->print(AP.OutStreamer.GetCommentOS());
1800 AP.OutStreamer.GetCommentOS() << ' ' << StrVal << '\n';
1803 // Now iterate through the APInt chunks, emitting them in endian-correct
1804 // order, possibly with a smaller chunk at beginning/end (e.g. for x87 80-bit
1806 unsigned NumBytes = API.getBitWidth() / 8;
1807 unsigned TrailingBytes = NumBytes % sizeof(uint64_t);
1808 const uint64_t *p = API.getRawData();
1810 // PPC's long double has odd notions of endianness compared to how LLVM
1811 // handles it: p[0] goes first for *big* endian on PPC.
1812 if (AP.TM.getDataLayout()->isBigEndian() != CFP->getType()->isPPC_FP128Ty()) {
1813 int Chunk = API.getNumWords() - 1;
1816 AP.OutStreamer.EmitIntValue(p[Chunk--], TrailingBytes);
1818 for (; Chunk >= 0; --Chunk)
1819 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1822 for (Chunk = 0; Chunk < NumBytes / sizeof(uint64_t); ++Chunk)
1823 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1826 AP.OutStreamer.EmitIntValue(p[Chunk], TrailingBytes);
1829 // Emit the tail padding for the long double.
1830 const DataLayout &DL = *AP.TM.getDataLayout();
1831 AP.OutStreamer.EmitZeros(DL.getTypeAllocSize(CFP->getType()) -
1832 DL.getTypeStoreSize(CFP->getType()));
1835 static void emitGlobalConstantLargeInt(const ConstantInt *CI, AsmPrinter &AP) {
1836 const DataLayout *DL = AP.TM.getDataLayout();
1837 unsigned BitWidth = CI->getBitWidth();
1839 // Copy the value as we may massage the layout for constants whose bit width
1840 // is not a multiple of 64-bits.
1841 APInt Realigned(CI->getValue());
1842 uint64_t ExtraBits = 0;
1843 unsigned ExtraBitsSize = BitWidth & 63;
1845 if (ExtraBitsSize) {
1846 // The bit width of the data is not a multiple of 64-bits.
1847 // The extra bits are expected to be at the end of the chunk of the memory.
1849 // * Nothing to be done, just record the extra bits to emit.
1851 // * Record the extra bits to emit.
1852 // * Realign the raw data to emit the chunks of 64-bits.
1853 if (DL->isBigEndian()) {
1854 // Basically the structure of the raw data is a chunk of 64-bits cells:
1855 // 0 1 BitWidth / 64
1856 // [chunk1][chunk2] ... [chunkN].
1857 // The most significant chunk is chunkN and it should be emitted first.
1858 // However, due to the alignment issue chunkN contains useless bits.
1859 // Realign the chunks so that they contain only useless information:
1860 // ExtraBits 0 1 (BitWidth / 64) - 1
1861 // chu[nk1 chu][nk2 chu] ... [nkN-1 chunkN]
1862 ExtraBits = Realigned.getRawData()[0] &
1863 (((uint64_t)-1) >> (64 - ExtraBitsSize));
1864 Realigned = Realigned.lshr(ExtraBitsSize);
1866 ExtraBits = Realigned.getRawData()[BitWidth / 64];
1869 // We don't expect assemblers to support integer data directives
1870 // for more than 64 bits, so we emit the data in at most 64-bit
1871 // quantities at a time.
1872 const uint64_t *RawData = Realigned.getRawData();
1873 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1874 uint64_t Val = DL->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1875 AP.OutStreamer.EmitIntValue(Val, 8);
1878 if (ExtraBitsSize) {
1879 // Emit the extra bits after the 64-bits chunks.
1881 // Emit a directive that fills the expected size.
1882 uint64_t Size = AP.TM.getDataLayout()->getTypeAllocSize(CI->getType());
1883 Size -= (BitWidth / 64) * 8;
1884 assert(Size && Size * 8 >= ExtraBitsSize &&
1885 (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize)))
1886 == ExtraBits && "Directive too small for extra bits.");
1887 AP.OutStreamer.EmitIntValue(ExtraBits, Size);
1891 static void emitGlobalConstantImpl(const Constant *CV, AsmPrinter &AP) {
1892 const DataLayout *DL = AP.TM.getDataLayout();
1893 uint64_t Size = DL->getTypeAllocSize(CV->getType());
1894 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV))
1895 return AP.OutStreamer.EmitZeros(Size);
1897 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1904 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1905 CI->getZExtValue());
1906 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size);
1909 emitGlobalConstantLargeInt(CI, AP);
1914 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1915 return emitGlobalConstantFP(CFP, AP);
1917 if (isa<ConstantPointerNull>(CV)) {
1918 AP.OutStreamer.EmitIntValue(0, Size);
1922 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV))
1923 return emitGlobalConstantDataSequential(CDS, AP);
1925 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1926 return emitGlobalConstantArray(CVA, AP);
1928 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1929 return emitGlobalConstantStruct(CVS, AP);
1931 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
1932 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
1934 if (CE->getOpcode() == Instruction::BitCast)
1935 return emitGlobalConstantImpl(CE->getOperand(0), AP);
1938 // If the constant expression's size is greater than 64-bits, then we have
1939 // to emit the value in chunks. Try to constant fold the value and emit it
1941 Constant *New = ConstantFoldConstantExpression(CE, DL);
1942 if (New && New != CE)
1943 return emitGlobalConstantImpl(New, AP);
1947 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1948 return emitGlobalConstantVector(V, AP);
1950 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1951 // thread the streamer with EmitValue.
1952 AP.OutStreamer.EmitValue(lowerConstant(CV, AP), Size);
1955 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1956 void AsmPrinter::EmitGlobalConstant(const Constant *CV) {
1957 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(CV->getType());
1959 emitGlobalConstantImpl(CV, *this);
1960 else if (MAI->hasSubsectionsViaSymbols()) {
1961 // If the global has zero size, emit a single byte so that two labels don't
1962 // look like they are at the same location.
1963 OutStreamer.EmitIntValue(0, 1);
1967 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1968 // Target doesn't support this yet!
1969 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1972 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1974 OS << '+' << Offset;
1975 else if (Offset < 0)
1979 //===----------------------------------------------------------------------===//
1980 // Symbol Lowering Routines.
1981 //===----------------------------------------------------------------------===//
1983 /// GetTempSymbol - Return the MCSymbol corresponding to the assembler
1984 /// temporary label with the specified stem and unique ID.
1985 MCSymbol *AsmPrinter::GetTempSymbol(Twine Name, unsigned ID) const {
1986 const DataLayout *DL = TM.getDataLayout();
1987 return OutContext.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix()) +
1991 /// GetTempSymbol - Return an assembler temporary label with the specified
1993 MCSymbol *AsmPrinter::GetTempSymbol(Twine Name) const {
1994 const DataLayout *DL = TM.getDataLayout();
1995 return OutContext.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix())+
2000 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
2001 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
2004 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
2005 return MMI->getAddrLabelSymbol(BB);
2008 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
2009 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
2010 const DataLayout *DL = TM.getDataLayout();
2011 return OutContext.GetOrCreateSymbol
2012 (Twine(DL->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
2013 + "_" + Twine(CPID));
2016 /// GetJTISymbol - Return the symbol for the specified jump table entry.
2017 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
2018 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
2021 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
2022 /// FIXME: privatize to AsmPrinter.
2023 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
2024 const DataLayout *DL = TM.getDataLayout();
2025 return OutContext.GetOrCreateSymbol
2026 (Twine(DL->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
2027 Twine(UID) + "_set_" + Twine(MBBID));
2030 MCSymbol *AsmPrinter::getSymbolWithGlobalValueBase(const GlobalValue *GV,
2031 StringRef Suffix) const {
2032 return getObjFileLowering().getSymbolWithGlobalValueBase(GV, Suffix, *Mang,
2036 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
2038 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
2039 SmallString<60> NameStr;
2040 Mang->getNameWithPrefix(NameStr, Sym);
2041 return OutContext.GetOrCreateSymbol(NameStr.str());
2046 /// PrintParentLoopComment - Print comments about parent loops of this one.
2047 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2048 unsigned FunctionNumber) {
2050 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
2051 OS.indent(Loop->getLoopDepth()*2)
2052 << "Parent Loop BB" << FunctionNumber << "_"
2053 << Loop->getHeader()->getNumber()
2054 << " Depth=" << Loop->getLoopDepth() << '\n';
2058 /// PrintChildLoopComment - Print comments about child loops within
2059 /// the loop for this basic block, with nesting.
2060 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2061 unsigned FunctionNumber) {
2062 // Add child loop information
2063 for (const MachineLoop *CL : *Loop) {
2064 OS.indent(CL->getLoopDepth()*2)
2065 << "Child Loop BB" << FunctionNumber << "_"
2066 << CL->getHeader()->getNumber() << " Depth " << CL->getLoopDepth()
2068 PrintChildLoopComment(OS, CL, FunctionNumber);
2072 /// emitBasicBlockLoopComments - Pretty-print comments for basic blocks.
2073 static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
2074 const MachineLoopInfo *LI,
2075 const AsmPrinter &AP) {
2076 // Add loop depth information
2077 const MachineLoop *Loop = LI->getLoopFor(&MBB);
2080 MachineBasicBlock *Header = Loop->getHeader();
2081 assert(Header && "No header for loop");
2083 // If this block is not a loop header, just print out what is the loop header
2085 if (Header != &MBB) {
2086 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
2087 Twine(AP.getFunctionNumber())+"_" +
2088 Twine(Loop->getHeader()->getNumber())+
2089 " Depth="+Twine(Loop->getLoopDepth()));
2093 // Otherwise, it is a loop header. Print out information about child and
2095 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
2097 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
2100 OS.indent(Loop->getLoopDepth()*2-2);
2105 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
2107 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
2111 /// EmitBasicBlockStart - This method prints the label for the specified
2112 /// MachineBasicBlock, an alignment (if present) and a comment describing
2113 /// it if appropriate.
2114 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock &MBB) const {
2115 // Emit an alignment directive for this block, if needed.
2116 if (unsigned Align = MBB.getAlignment())
2117 EmitAlignment(Align);
2119 // If the block has its address taken, emit any labels that were used to
2120 // reference the block. It is possible that there is more than one label
2121 // here, because multiple LLVM BB's may have been RAUW'd to this block after
2122 // the references were generated.
2123 if (MBB.hasAddressTaken()) {
2124 const BasicBlock *BB = MBB.getBasicBlock();
2126 OutStreamer.AddComment("Block address taken");
2128 std::vector<MCSymbol*> Symbols = MMI->getAddrLabelSymbolToEmit(BB);
2129 for (auto *Sym : Symbols)
2130 OutStreamer.EmitLabel(Sym);
2133 // Print some verbose block comments.
2135 if (const BasicBlock *BB = MBB.getBasicBlock())
2137 OutStreamer.AddComment("%" + BB->getName());
2138 emitBasicBlockLoopComments(MBB, LI, *this);
2141 // Print the main label for the block.
2142 if (MBB.pred_empty() || isBlockOnlyReachableByFallthrough(&MBB)) {
2144 // NOTE: Want this comment at start of line, don't emit with AddComment.
2145 OutStreamer.emitRawComment(" BB#" + Twine(MBB.getNumber()) + ":", false);
2148 OutStreamer.EmitLabel(MBB.getSymbol());
2152 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility,
2153 bool IsDefinition) const {
2154 MCSymbolAttr Attr = MCSA_Invalid;
2156 switch (Visibility) {
2158 case GlobalValue::HiddenVisibility:
2160 Attr = MAI->getHiddenVisibilityAttr();
2162 Attr = MAI->getHiddenDeclarationVisibilityAttr();
2164 case GlobalValue::ProtectedVisibility:
2165 Attr = MAI->getProtectedVisibilityAttr();
2169 if (Attr != MCSA_Invalid)
2170 OutStreamer.EmitSymbolAttribute(Sym, Attr);
2173 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
2174 /// exactly one predecessor and the control transfer mechanism between
2175 /// the predecessor and this block is a fall-through.
2177 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
2178 // If this is a landing pad, it isn't a fall through. If it has no preds,
2179 // then nothing falls through to it.
2180 if (MBB->isLandingPad() || MBB->pred_empty())
2183 // If there isn't exactly one predecessor, it can't be a fall through.
2184 if (MBB->pred_size() > 1)
2187 // The predecessor has to be immediately before this block.
2188 MachineBasicBlock *Pred = *MBB->pred_begin();
2189 if (!Pred->isLayoutSuccessor(MBB))
2192 // If the block is completely empty, then it definitely does fall through.
2196 // Check the terminators in the previous blocks
2197 for (const auto &MI : Pred->terminators()) {
2198 // If it is not a simple branch, we are in a table somewhere.
2199 if (!MI.isBranch() || MI.isIndirectBranch())
2202 // If we are the operands of one of the branches, this is not a fall
2203 // through. Note that targets with delay slots will usually bundle
2204 // terminators with the delay slot instruction.
2205 for (ConstMIBundleOperands OP(&MI); OP.isValid(); ++OP) {
2208 if (OP->isMBB() && OP->getMBB() == MBB)
2218 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy &S) {
2219 if (!S.usesMetadata())
2222 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
2223 gcp_map_type::iterator GCPI = GCMap.find(&S);
2224 if (GCPI != GCMap.end())
2225 return GCPI->second.get();
2227 const char *Name = S.getName().c_str();
2229 for (GCMetadataPrinterRegistry::iterator
2230 I = GCMetadataPrinterRegistry::begin(),
2231 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
2232 if (strcmp(Name, I->getName()) == 0) {
2233 std::unique_ptr<GCMetadataPrinter> GMP = I->instantiate();
2235 auto IterBool = GCMap.insert(std::make_pair(&S, std::move(GMP)));
2236 return IterBool.first->second.get();
2239 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));
2242 /// Pin vtable to this file.
2243 AsmPrinterHandler::~AsmPrinterHandler() {}