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 #define DEBUG_TYPE "asm-printer"
15 #include "llvm/CodeGen/AsmPrinter.h"
16 #include "DwarfDebug.h"
17 #include "DwarfException.h"
18 #include "llvm/ADT/SmallString.h"
19 #include "llvm/ADT/Statistic.h"
20 #include "llvm/Analysis/ConstantFolding.h"
21 #include "llvm/Assembly/Writer.h"
22 #include "llvm/CodeGen/GCMetadataPrinter.h"
23 #include "llvm/CodeGen/MachineConstantPool.h"
24 #include "llvm/CodeGen/MachineFrameInfo.h"
25 #include "llvm/CodeGen/MachineFunction.h"
26 #include "llvm/CodeGen/MachineInstrBundle.h"
27 #include "llvm/CodeGen/MachineJumpTableInfo.h"
28 #include "llvm/CodeGen/MachineLoopInfo.h"
29 #include "llvm/CodeGen/MachineModuleInfo.h"
30 #include "llvm/DebugInfo.h"
31 #include "llvm/IR/DataLayout.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/Mangler.h"
46 #include "llvm/Target/TargetFrameLowering.h"
47 #include "llvm/Target/TargetInstrInfo.h"
48 #include "llvm/Target/TargetLowering.h"
49 #include "llvm/Target/TargetLoweringObjectFile.h"
50 #include "llvm/Target/TargetOptions.h"
51 #include "llvm/Target/TargetRegisterInfo.h"
52 #include "llvm/Transforms/Utils/GlobalStatus.h"
55 static const char *const DWARFGroupName = "DWARF Emission";
56 static const char *const DbgTimerName = "DWARF Debug Writer";
57 static const char *const EHTimerName = "DWARF Exception Writer";
59 STATISTIC(EmittedInsts, "Number of machine instrs printed");
61 char AsmPrinter::ID = 0;
63 typedef DenseMap<GCStrategy*,GCMetadataPrinter*> gcp_map_type;
64 static gcp_map_type &getGCMap(void *&P) {
66 P = new gcp_map_type();
67 return *(gcp_map_type*)P;
71 /// getGVAlignmentLog2 - Return the alignment to use for the specified global
72 /// value in log2 form. This rounds up to the preferred alignment if possible
74 static unsigned getGVAlignmentLog2(const GlobalValue *GV, const DataLayout &TD,
75 unsigned InBits = 0) {
77 if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV))
78 NumBits = TD.getPreferredAlignmentLog(GVar);
80 // If InBits is specified, round it to it.
84 // If the GV has a specified alignment, take it into account.
85 if (GV->getAlignment() == 0)
88 unsigned GVAlign = Log2_32(GV->getAlignment());
90 // If the GVAlign is larger than NumBits, or if we are required to obey
91 // NumBits because the GV has an assigned section, obey it.
92 if (GVAlign > NumBits || GV->hasSection())
97 AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
98 : MachineFunctionPass(ID),
99 TM(tm), MAI(tm.getMCAsmInfo()), MII(tm.getInstrInfo()),
100 OutContext(Streamer.getContext()),
101 OutStreamer(Streamer),
102 LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {
103 DD = 0; DE = 0; MMI = 0; LI = 0; MF = 0;
104 CurrentFnSym = CurrentFnSymForSize = 0;
105 GCMetadataPrinters = 0;
106 VerboseAsm = Streamer.isVerboseAsm();
109 AsmPrinter::~AsmPrinter() {
110 assert(DD == 0 && DE == 0 && "Debug/EH info didn't get finalized");
112 if (GCMetadataPrinters != 0) {
113 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
115 for (gcp_map_type::iterator I = GCMap.begin(), E = GCMap.end(); I != E; ++I)
118 GCMetadataPrinters = 0;
124 /// getFunctionNumber - Return a unique ID for the current function.
126 unsigned AsmPrinter::getFunctionNumber() const {
127 return MF->getFunctionNumber();
130 const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
131 return TM.getTargetLowering()->getObjFileLowering();
134 /// getDataLayout - Return information about data layout.
135 const DataLayout &AsmPrinter::getDataLayout() const {
136 return *TM.getDataLayout();
139 StringRef AsmPrinter::getTargetTriple() const {
140 return TM.getTargetTriple();
143 /// getCurrentSection() - Return the current section we are emitting to.
144 const MCSection *AsmPrinter::getCurrentSection() const {
145 return OutStreamer.getCurrentSection().first;
150 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
151 AU.setPreservesAll();
152 MachineFunctionPass::getAnalysisUsage(AU);
153 AU.addRequired<MachineModuleInfo>();
154 AU.addRequired<GCModuleInfo>();
156 AU.addRequired<MachineLoopInfo>();
159 bool AsmPrinter::doInitialization(Module &M) {
160 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
161 MMI->AnalyzeModule(M);
163 // Initialize TargetLoweringObjectFile.
164 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
165 .Initialize(OutContext, TM);
167 OutStreamer.InitStreamer();
169 Mang = new Mangler(&TM);
171 // Allow the target to emit any magic that it wants at the start of the file.
172 EmitStartOfAsmFile(M);
174 // Very minimal debug info. It is ignored if we emit actual debug info. If we
175 // don't, this at least helps the user find where a global came from.
176 if (MAI->hasSingleParameterDotFile()) {
178 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
181 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
182 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
183 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
184 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
185 MP->beginAssembly(*this);
187 // Emit module-level inline asm if it exists.
188 if (!M.getModuleInlineAsm().empty()) {
189 OutStreamer.AddComment("Start of file scope inline assembly");
190 OutStreamer.AddBlankLine();
191 EmitInlineAsm(M.getModuleInlineAsm()+"\n");
192 OutStreamer.AddComment("End of file scope inline assembly");
193 OutStreamer.AddBlankLine();
196 if (MAI->doesSupportDebugInformation())
197 DD = new DwarfDebug(this, &M);
199 switch (MAI->getExceptionHandlingType()) {
200 case ExceptionHandling::None:
202 case ExceptionHandling::SjLj:
203 case ExceptionHandling::DwarfCFI:
204 DE = new DwarfCFIException(this);
206 case ExceptionHandling::ARM:
207 DE = new ARMException(this);
209 case ExceptionHandling::Win64:
210 DE = new Win64Exception(this);
214 llvm_unreachable("Unknown exception type.");
217 void AsmPrinter::EmitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const {
218 GlobalValue::LinkageTypes Linkage = GV->getLinkage();
220 case GlobalValue::CommonLinkage:
221 case GlobalValue::LinkOnceAnyLinkage:
222 case GlobalValue::LinkOnceODRLinkage:
223 case GlobalValue::WeakAnyLinkage:
224 case GlobalValue::WeakODRLinkage:
225 case GlobalValue::LinkerPrivateWeakLinkage:
226 if (MAI->hasWeakDefDirective()) {
228 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
230 bool CanBeHidden = false;
232 if (Linkage == GlobalValue::LinkOnceODRLinkage &&
233 MAI->hasWeakDefCanBeHiddenDirective()) {
234 if (GV->hasUnnamedAddr()) {
238 if (!GlobalStatus::analyzeGlobal(GV, GS) && !GS.IsCompared)
244 // .weak_definition _foo
245 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
247 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefAutoPrivate);
248 } else if (MAI->hasLinkOnceDirective()) {
250 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
251 //NOTE: linkonce is handled by the section the symbol was assigned to.
254 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
257 case GlobalValue::DLLExportLinkage:
258 case GlobalValue::AppendingLinkage:
259 // FIXME: appending linkage variables should go into a section of
260 // their name or something. For now, just emit them as external.
261 case GlobalValue::ExternalLinkage:
262 // If external or appending, declare as a global symbol.
264 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
266 case GlobalValue::PrivateLinkage:
267 case GlobalValue::InternalLinkage:
268 case GlobalValue::LinkerPrivateLinkage:
270 case GlobalValue::AvailableExternallyLinkage:
271 llvm_unreachable("Should never emit this");
272 case GlobalValue::DLLImportLinkage:
273 case GlobalValue::ExternalWeakLinkage:
274 llvm_unreachable("Don't know how to emit these");
276 llvm_unreachable("Unknown linkage type!");
279 MCSymbol *AsmPrinter::getSymbol(const GlobalValue *GV) const {
280 return getObjFileLowering().getSymbol(*Mang, GV);
283 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
284 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
285 if (GV->hasInitializer()) {
286 // Check to see if this is a special global used by LLVM, if so, emit it.
287 if (EmitSpecialLLVMGlobal(GV))
291 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
292 /*PrintType=*/false, GV->getParent());
293 OutStreamer.GetCommentOS() << '\n';
297 MCSymbol *GVSym = getSymbol(GV);
298 EmitVisibility(GVSym, GV->getVisibility(), !GV->isDeclaration());
300 if (!GV->hasInitializer()) // External globals require no extra code.
303 if (MAI->hasDotTypeDotSizeDirective())
304 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
306 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
308 const DataLayout *DL = TM.getDataLayout();
309 uint64_t Size = DL->getTypeAllocSize(GV->getType()->getElementType());
311 // If the alignment is specified, we *must* obey it. Overaligning a global
312 // with a specified alignment is a prompt way to break globals emitted to
313 // sections and expected to be contiguous (e.g. ObjC metadata).
314 unsigned AlignLog = getGVAlignmentLog2(GV, *DL);
317 DD->setSymbolSize(GVSym, Size);
319 // Handle common and BSS local symbols (.lcomm).
320 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
321 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
322 unsigned Align = 1 << AlignLog;
324 // Handle common symbols.
325 if (GVKind.isCommon()) {
326 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
330 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
334 // Handle local BSS symbols.
335 if (MAI->hasMachoZeroFillDirective()) {
336 const MCSection *TheSection =
337 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
338 // .zerofill __DATA, __bss, _foo, 400, 5
339 OutStreamer.EmitZerofill(TheSection, GVSym, Size, Align);
343 // Use .lcomm only if it supports user-specified alignment.
344 // Otherwise, while it would still be correct to use .lcomm in some
345 // cases (e.g. when Align == 1), the external assembler might enfore
346 // some -unknown- default alignment behavior, which could cause
347 // spurious differences between external and integrated assembler.
348 // Prefer to simply fall back to .local / .comm in this case.
349 if (MAI->getLCOMMDirectiveAlignmentType() != LCOMM::NoAlignment) {
351 OutStreamer.EmitLocalCommonSymbol(GVSym, Size, Align);
355 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
359 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
361 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
365 const MCSection *TheSection =
366 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
368 // Handle the zerofill directive on darwin, which is a special form of BSS
370 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
371 if (Size == 0) Size = 1; // zerofill of 0 bytes is undefined.
374 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
375 // .zerofill __DATA, __common, _foo, 400, 5
376 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
380 // Handle thread local data for mach-o which requires us to output an
381 // additional structure of data and mangle the original symbol so that we
382 // can reference it later.
384 // TODO: This should become an "emit thread local global" method on TLOF.
385 // All of this macho specific stuff should be sunk down into TLOFMachO and
386 // stuff like "TLSExtraDataSection" should no longer be part of the parent
387 // TLOF class. This will also make it more obvious that stuff like
388 // MCStreamer::EmitTBSSSymbol is macho specific and only called from macho
390 if (GVKind.isThreadLocal() && MAI->hasMachoTBSSDirective()) {
391 // Emit the .tbss symbol
393 OutContext.GetOrCreateSymbol(GVSym->getName() + Twine("$tlv$init"));
395 if (GVKind.isThreadBSS()) {
396 TheSection = getObjFileLowering().getTLSBSSSection();
397 OutStreamer.EmitTBSSSymbol(TheSection, MangSym, Size, 1 << AlignLog);
398 } else if (GVKind.isThreadData()) {
399 OutStreamer.SwitchSection(TheSection);
401 EmitAlignment(AlignLog, GV);
402 OutStreamer.EmitLabel(MangSym);
404 EmitGlobalConstant(GV->getInitializer());
407 OutStreamer.AddBlankLine();
409 // Emit the variable struct for the runtime.
410 const MCSection *TLVSect
411 = getObjFileLowering().getTLSExtraDataSection();
413 OutStreamer.SwitchSection(TLVSect);
414 // Emit the linkage here.
415 EmitLinkage(GV, GVSym);
416 OutStreamer.EmitLabel(GVSym);
418 // Three pointers in size:
419 // - __tlv_bootstrap - used to make sure support exists
420 // - spare pointer, used when mapped by the runtime
421 // - pointer to mangled symbol above with initializer
422 unsigned PtrSize = DL->getPointerTypeSize(GV->getType());
423 OutStreamer.EmitSymbolValue(GetExternalSymbolSymbol("_tlv_bootstrap"),
425 OutStreamer.EmitIntValue(0, PtrSize);
426 OutStreamer.EmitSymbolValue(MangSym, PtrSize);
428 OutStreamer.AddBlankLine();
432 OutStreamer.SwitchSection(TheSection);
434 EmitLinkage(GV, GVSym);
435 EmitAlignment(AlignLog, GV);
437 OutStreamer.EmitLabel(GVSym);
439 EmitGlobalConstant(GV->getInitializer());
441 if (MAI->hasDotTypeDotSizeDirective())
443 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
445 OutStreamer.AddBlankLine();
448 /// EmitFunctionHeader - This method emits the header for the current
450 void AsmPrinter::EmitFunctionHeader() {
451 // Print out constants referenced by the function
454 // Print the 'header' of function.
455 const Function *F = MF->getFunction();
457 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
458 EmitVisibility(CurrentFnSym, F->getVisibility());
460 EmitLinkage(F, CurrentFnSym);
461 EmitAlignment(MF->getAlignment(), F);
463 if (MAI->hasDotTypeDotSizeDirective())
464 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
467 WriteAsOperand(OutStreamer.GetCommentOS(), F,
468 /*PrintType=*/false, F->getParent());
469 OutStreamer.GetCommentOS() << '\n';
472 // Emit the CurrentFnSym. This is a virtual function to allow targets to
473 // do their wild and crazy things as required.
474 EmitFunctionEntryLabel();
476 // If the function had address-taken blocks that got deleted, then we have
477 // references to the dangling symbols. Emit them at the start of the function
478 // so that we don't get references to undefined symbols.
479 std::vector<MCSymbol*> DeadBlockSyms;
480 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
481 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
482 OutStreamer.AddComment("Address taken block that was later removed");
483 OutStreamer.EmitLabel(DeadBlockSyms[i]);
486 // Emit pre-function debug and/or EH information.
488 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled);
489 DE->BeginFunction(MF);
492 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
493 DD->beginFunction(MF);
496 // Emit the prefix data.
497 if (F->hasPrefixData())
498 EmitGlobalConstant(F->getPrefixData());
501 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
502 /// function. This can be overridden by targets as required to do custom stuff.
503 void AsmPrinter::EmitFunctionEntryLabel() {
504 // The function label could have already been emitted if two symbols end up
505 // conflicting due to asm renaming. Detect this and emit an error.
506 if (CurrentFnSym->isUndefined())
507 return OutStreamer.EmitLabel(CurrentFnSym);
509 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
510 "' label emitted multiple times to assembly file");
513 /// emitComments - Pretty-print comments for instructions.
514 static void emitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
515 const MachineFunction *MF = MI.getParent()->getParent();
516 const TargetMachine &TM = MF->getTarget();
518 // Check for spills and reloads
521 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
523 // We assume a single instruction only has a spill or reload, not
525 const MachineMemOperand *MMO;
526 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
527 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
528 MMO = *MI.memoperands_begin();
529 CommentOS << MMO->getSize() << "-byte Reload\n";
531 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
532 if (FrameInfo->isSpillSlotObjectIndex(FI))
533 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
534 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
535 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
536 MMO = *MI.memoperands_begin();
537 CommentOS << MMO->getSize() << "-byte Spill\n";
539 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
540 if (FrameInfo->isSpillSlotObjectIndex(FI))
541 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
544 // Check for spill-induced copies
545 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
546 CommentOS << " Reload Reuse\n";
549 /// emitImplicitDef - This method emits the specified machine instruction
550 /// that is an implicit def.
551 void AsmPrinter::emitImplicitDef(const MachineInstr *MI) const {
552 unsigned RegNo = MI->getOperand(0).getReg();
553 OutStreamer.AddComment(Twine("implicit-def: ") +
554 TM.getRegisterInfo()->getName(RegNo));
555 OutStreamer.AddBlankLine();
558 static void emitKill(const MachineInstr *MI, AsmPrinter &AP) {
559 std::string Str = "kill:";
560 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
561 const MachineOperand &Op = MI->getOperand(i);
562 assert(Op.isReg() && "KILL instruction must have only register operands");
564 Str += AP.TM.getRegisterInfo()->getName(Op.getReg());
565 Str += (Op.isDef() ? "<def>" : "<kill>");
567 AP.OutStreamer.AddComment(Str);
568 AP.OutStreamer.AddBlankLine();
571 /// emitDebugValueComment - This method handles the target-independent form
572 /// of DBG_VALUE, returning true if it was able to do so. A false return
573 /// means the target will need to handle MI in EmitInstruction.
574 static bool emitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
575 // This code handles only the 3-operand target-independent form.
576 if (MI->getNumOperands() != 3)
579 SmallString<128> Str;
580 raw_svector_ostream OS(Str);
581 OS << '\t' << AP.MAI->getCommentString() << "DEBUG_VALUE: ";
583 // cast away const; DIetc do not take const operands for some reason.
584 DIVariable V(const_cast<MDNode*>(MI->getOperand(2).getMetadata()));
585 if (V.getContext().isSubprogram()) {
586 StringRef Name = DISubprogram(V.getContext()).getDisplayName();
590 OS << V.getName() << " <- ";
592 // The second operand is only an offset if it's an immediate.
593 bool Deref = MI->getOperand(0).isReg() && MI->getOperand(1).isImm();
594 int64_t Offset = Deref ? MI->getOperand(1).getImm() : 0;
596 // Register or immediate value. Register 0 means undef.
597 if (MI->getOperand(0).isFPImm()) {
598 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
599 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
600 OS << (double)APF.convertToFloat();
601 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
602 OS << APF.convertToDouble();
604 // There is no good way to print long double. Convert a copy to
605 // double. Ah well, it's only a comment.
607 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
609 OS << "(long double) " << APF.convertToDouble();
611 } else if (MI->getOperand(0).isImm()) {
612 OS << MI->getOperand(0).getImm();
613 } else if (MI->getOperand(0).isCImm()) {
614 MI->getOperand(0).getCImm()->getValue().print(OS, false /*isSigned*/);
617 if (MI->getOperand(0).isReg()) {
618 Reg = MI->getOperand(0).getReg();
620 assert(MI->getOperand(0).isFI() && "Unknown operand type");
621 const TargetFrameLowering *TFI = AP.TM.getFrameLowering();
622 Offset += TFI->getFrameIndexReference(*AP.MF,
623 MI->getOperand(0).getIndex(), Reg);
627 // Suppress offset, it is not meaningful here.
629 // NOTE: Want this comment at start of line, don't emit with AddComment.
630 AP.OutStreamer.EmitRawText(OS.str());
635 OS << AP.TM.getRegisterInfo()->getName(Reg);
639 OS << '+' << Offset << ']';
641 // NOTE: Want this comment at start of line, don't emit with AddComment.
642 AP.OutStreamer.EmitRawText(OS.str());
646 AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() {
647 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI &&
648 MF->getFunction()->needsUnwindTableEntry())
651 if (MMI->hasDebugInfo())
657 bool AsmPrinter::needsSEHMoves() {
658 return MAI->getExceptionHandlingType() == ExceptionHandling::Win64 &&
659 MF->getFunction()->needsUnwindTableEntry();
662 bool AsmPrinter::needsRelocationsForDwarfStringPool() const {
663 return MAI->doesDwarfUseRelocationsAcrossSections();
666 void AsmPrinter::emitPrologLabel(const MachineInstr &MI) {
667 const MCSymbol *Label = MI.getOperand(0).getMCSymbol();
669 if (MAI->getExceptionHandlingType() != ExceptionHandling::DwarfCFI)
672 if (needsCFIMoves() == CFI_M_None)
675 if (MMI->getCompactUnwindEncoding() != 0)
676 OutStreamer.EmitCompactUnwindEncoding(MMI->getCompactUnwindEncoding());
678 const MachineModuleInfo &MMI = MF->getMMI();
679 const std::vector<MCCFIInstruction> &Instrs = MMI.getFrameInstructions();
680 bool FoundOne = false;
682 for (std::vector<MCCFIInstruction>::const_iterator I = Instrs.begin(),
683 E = Instrs.end(); I != E; ++I) {
684 if (I->getLabel() == Label) {
685 emitCFIInstruction(*I);
692 /// EmitFunctionBody - This method emits the body and trailer for a
694 void AsmPrinter::EmitFunctionBody() {
695 // Emit target-specific gunk before the function body.
696 EmitFunctionBodyStart();
698 bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo();
700 // Print out code for the function.
701 bool HasAnyRealCode = false;
702 const MachineInstr *LastMI = 0;
703 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
705 // Print a label for the basic block.
706 EmitBasicBlockStart(I);
707 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
711 // Print the assembly for the instruction.
712 if (!II->isLabel() && !II->isImplicitDef() && !II->isKill() &&
713 !II->isDebugValue()) {
714 HasAnyRealCode = true;
718 if (ShouldPrintDebugScopes) {
719 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
720 DD->beginInstruction(II);
724 emitComments(*II, OutStreamer.GetCommentOS());
726 switch (II->getOpcode()) {
727 case TargetOpcode::PROLOG_LABEL:
728 emitPrologLabel(*II);
731 case TargetOpcode::EH_LABEL:
732 case TargetOpcode::GC_LABEL:
733 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol());
735 case TargetOpcode::INLINEASM:
738 case TargetOpcode::DBG_VALUE:
740 if (!emitDebugValueComment(II, *this))
744 case TargetOpcode::IMPLICIT_DEF:
745 if (isVerbose()) emitImplicitDef(II);
747 case TargetOpcode::KILL:
748 if (isVerbose()) emitKill(II, *this);
751 if (!TM.hasMCUseLoc())
752 MCLineEntry::Make(&OutStreamer, getCurrentSection());
758 if (ShouldPrintDebugScopes) {
759 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
760 DD->endInstruction(II);
765 // If the last instruction was a prolog label, then we have a situation where
766 // we emitted a prolog but no function body. This results in the ending prolog
767 // label equaling the end of function label and an invalid "row" in the
768 // FDE. We need to emit a noop in this situation so that the FDE's rows are
770 bool RequiresNoop = LastMI && LastMI->isPrologLabel();
772 // If the function is empty and the object file uses .subsections_via_symbols,
773 // then we need to emit *something* to the function body to prevent the
774 // labels from collapsing together. Just emit a noop.
775 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) || RequiresNoop) {
777 TM.getInstrInfo()->getNoopForMachoTarget(Noop);
778 if (Noop.getOpcode()) {
779 OutStreamer.AddComment("avoids zero-length function");
780 OutStreamer.EmitInstruction(Noop);
781 } else // Target not mc-ized yet.
782 OutStreamer.EmitRawText(StringRef("\tnop\n"));
785 const Function *F = MF->getFunction();
786 for (Function::const_iterator i = F->begin(), e = F->end(); i != e; ++i) {
787 const BasicBlock *BB = i;
788 if (!BB->hasAddressTaken())
790 MCSymbol *Sym = GetBlockAddressSymbol(BB);
791 if (Sym->isDefined())
793 OutStreamer.AddComment("Address of block that was removed by CodeGen");
794 OutStreamer.EmitLabel(Sym);
797 // Emit target-specific gunk after the function body.
798 EmitFunctionBodyEnd();
800 // If the target wants a .size directive for the size of the function, emit
802 if (MAI->hasDotTypeDotSizeDirective()) {
803 // Create a symbol for the end of function, so we can get the size as
804 // difference between the function label and the temp label.
805 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
806 OutStreamer.EmitLabel(FnEndLabel);
808 const MCExpr *SizeExp =
809 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
810 MCSymbolRefExpr::Create(CurrentFnSymForSize,
813 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
816 // Emit post-function debug information.
818 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
822 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled);
827 // Print out jump tables referenced by the function.
830 OutStreamer.AddBlankLine();
833 /// EmitDwarfRegOp - Emit dwarf register operation.
834 void AsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc,
835 bool Indirect) const {
836 const TargetRegisterInfo *TRI = TM.getRegisterInfo();
837 int Reg = TRI->getDwarfRegNum(MLoc.getReg(), false);
839 for (MCSuperRegIterator SR(MLoc.getReg(), TRI); SR.isValid() && Reg < 0;
841 Reg = TRI->getDwarfRegNum(*SR, false);
842 // FIXME: Get the bit range this register uses of the superregister
843 // so that we can produce a DW_OP_bit_piece
846 // FIXME: Handle cases like a super register being encoded as
847 // DW_OP_reg 32 DW_OP_piece 4 DW_OP_reg 33
849 // FIXME: We have no reasonable way of handling errors in here. The
850 // caller might be in the middle of an dwarf expression. We should
851 // probably assert that Reg >= 0 once debug info generation is more mature.
853 if (MLoc.isIndirect() || Indirect) {
855 OutStreamer.AddComment(
856 dwarf::OperationEncodingString(dwarf::DW_OP_breg0 + Reg));
857 EmitInt8(dwarf::DW_OP_breg0 + Reg);
859 OutStreamer.AddComment("DW_OP_bregx");
860 EmitInt8(dwarf::DW_OP_bregx);
861 OutStreamer.AddComment(Twine(Reg));
864 EmitSLEB128(!MLoc.isIndirect() ? 0 : MLoc.getOffset());
865 if (MLoc.isIndirect() && Indirect)
866 EmitInt8(dwarf::DW_OP_deref);
869 OutStreamer.AddComment(
870 dwarf::OperationEncodingString(dwarf::DW_OP_reg0 + Reg));
871 EmitInt8(dwarf::DW_OP_reg0 + Reg);
873 OutStreamer.AddComment("DW_OP_regx");
874 EmitInt8(dwarf::DW_OP_regx);
875 OutStreamer.AddComment(Twine(Reg));
880 // FIXME: Produce a DW_OP_bit_piece if we used a superregister
883 bool AsmPrinter::doFinalization(Module &M) {
884 // Emit global variables.
885 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
887 EmitGlobalVariable(I);
889 // Emit visibility info for declarations
890 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
891 const Function &F = *I;
892 if (!F.isDeclaration())
894 GlobalValue::VisibilityTypes V = F.getVisibility();
895 if (V == GlobalValue::DefaultVisibility)
898 MCSymbol *Name = getSymbol(&F);
899 EmitVisibility(Name, V, false);
902 // Emit module flags.
903 SmallVector<Module::ModuleFlagEntry, 8> ModuleFlags;
904 M.getModuleFlagsMetadata(ModuleFlags);
905 if (!ModuleFlags.empty())
906 getObjFileLowering().emitModuleFlags(OutStreamer, ModuleFlags, Mang, TM);
908 // Make sure we wrote out everything we need.
911 // Finalize debug and EH information.
914 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled);
921 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
927 // If the target wants to know about weak references, print them all.
928 if (MAI->getWeakRefDirective()) {
929 // FIXME: This is not lazy, it would be nice to only print weak references
930 // to stuff that is actually used. Note that doing so would require targets
931 // to notice uses in operands (due to constant exprs etc). This should
932 // happen with the MC stuff eventually.
934 // Print out module-level global variables here.
935 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
937 if (!I->hasExternalWeakLinkage()) continue;
938 OutStreamer.EmitSymbolAttribute(getSymbol(I), MCSA_WeakReference);
941 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
942 if (!I->hasExternalWeakLinkage()) continue;
943 OutStreamer.EmitSymbolAttribute(getSymbol(I), MCSA_WeakReference);
947 if (MAI->hasSetDirective()) {
948 OutStreamer.AddBlankLine();
949 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
951 MCSymbol *Name = getSymbol(I);
953 const GlobalValue *GV = I->getAliasedGlobal();
954 if (GV->isDeclaration()) {
955 report_fatal_error(Name->getName() +
956 ": Target doesn't support aliases to declarations");
959 MCSymbol *Target = getSymbol(GV);
961 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
962 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
963 else if (I->hasWeakLinkage() || I->hasLinkOnceLinkage())
964 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
966 assert(I->hasLocalLinkage() && "Invalid alias linkage");
968 EmitVisibility(Name, I->getVisibility());
970 // Emit the directives as assignments aka .set:
971 OutStreamer.EmitAssignment(Name,
972 MCSymbolRefExpr::Create(Target, OutContext));
976 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
977 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
978 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
979 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
980 MP->finishAssembly(*this);
982 // Emit llvm.ident metadata in an '.ident' directive.
985 // If we don't have any trampolines, then we don't require stack memory
986 // to be executable. Some targets have a directive to declare this.
987 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
988 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
989 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext))
990 OutStreamer.SwitchSection(S);
992 // Allow the target to emit any magic that it wants at the end of the file,
993 // after everything else has gone out.
996 delete Mang; Mang = 0;
999 OutStreamer.Finish();
1000 OutStreamer.reset();
1005 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
1007 // Get the function symbol.
1008 CurrentFnSym = getSymbol(MF.getFunction());
1009 CurrentFnSymForSize = CurrentFnSym;
1012 LI = &getAnalysis<MachineLoopInfo>();
1016 // SectionCPs - Keep track the alignment, constpool entries per Section.
1020 SmallVector<unsigned, 4> CPEs;
1021 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
1025 /// EmitConstantPool - Print to the current output stream assembly
1026 /// representations of the constants in the constant pool MCP. This is
1027 /// used to print out constants which have been "spilled to memory" by
1028 /// the code generator.
1030 void AsmPrinter::EmitConstantPool() {
1031 const MachineConstantPool *MCP = MF->getConstantPool();
1032 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
1033 if (CP.empty()) return;
1035 // Calculate sections for constant pool entries. We collect entries to go into
1036 // the same section together to reduce amount of section switch statements.
1037 SmallVector<SectionCPs, 4> CPSections;
1038 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
1039 const MachineConstantPoolEntry &CPE = CP[i];
1040 unsigned Align = CPE.getAlignment();
1043 switch (CPE.getRelocationInfo()) {
1044 default: llvm_unreachable("Unknown section kind");
1045 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
1047 Kind = SectionKind::getReadOnlyWithRelLocal();
1050 switch (TM.getDataLayout()->getTypeAllocSize(CPE.getType())) {
1051 case 4: Kind = SectionKind::getMergeableConst4(); break;
1052 case 8: Kind = SectionKind::getMergeableConst8(); break;
1053 case 16: Kind = SectionKind::getMergeableConst16();break;
1054 default: Kind = SectionKind::getMergeableConst(); break;
1058 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
1060 // The number of sections are small, just do a linear search from the
1061 // last section to the first.
1063 unsigned SecIdx = CPSections.size();
1064 while (SecIdx != 0) {
1065 if (CPSections[--SecIdx].S == S) {
1071 SecIdx = CPSections.size();
1072 CPSections.push_back(SectionCPs(S, Align));
1075 if (Align > CPSections[SecIdx].Alignment)
1076 CPSections[SecIdx].Alignment = Align;
1077 CPSections[SecIdx].CPEs.push_back(i);
1080 // Now print stuff into the calculated sections.
1081 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
1082 OutStreamer.SwitchSection(CPSections[i].S);
1083 EmitAlignment(Log2_32(CPSections[i].Alignment));
1085 unsigned Offset = 0;
1086 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
1087 unsigned CPI = CPSections[i].CPEs[j];
1088 MachineConstantPoolEntry CPE = CP[CPI];
1090 // Emit inter-object padding for alignment.
1091 unsigned AlignMask = CPE.getAlignment() - 1;
1092 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
1093 OutStreamer.EmitZeros(NewOffset - Offset);
1095 Type *Ty = CPE.getType();
1096 Offset = NewOffset + TM.getDataLayout()->getTypeAllocSize(Ty);
1097 OutStreamer.EmitLabel(GetCPISymbol(CPI));
1099 if (CPE.isMachineConstantPoolEntry())
1100 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
1102 EmitGlobalConstant(CPE.Val.ConstVal);
1107 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
1108 /// by the current function to the current output stream.
1110 void AsmPrinter::EmitJumpTableInfo() {
1111 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1112 if (MJTI == 0) return;
1113 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
1114 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1115 if (JT.empty()) return;
1117 // Pick the directive to use to print the jump table entries, and switch to
1118 // the appropriate section.
1119 const Function *F = MF->getFunction();
1120 bool JTInDiffSection = false;
1121 if (// In PIC mode, we need to emit the jump table to the same section as the
1122 // function body itself, otherwise the label differences won't make sense.
1123 // FIXME: Need a better predicate for this: what about custom entries?
1124 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
1125 // We should also do if the section name is NULL or function is declared
1126 // in discardable section
1127 // FIXME: this isn't the right predicate, should be based on the MCSection
1128 // for the function.
1129 F->isWeakForLinker()) {
1130 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
1132 // Otherwise, drop it in the readonly section.
1133 const MCSection *ReadOnlySection =
1134 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
1135 OutStreamer.SwitchSection(ReadOnlySection);
1136 JTInDiffSection = true;
1139 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getDataLayout())));
1141 // Jump tables in code sections are marked with a data_region directive
1142 // where that's supported.
1143 if (!JTInDiffSection)
1144 OutStreamer.EmitDataRegion(MCDR_DataRegionJT32);
1146 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
1147 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1149 // If this jump table was deleted, ignore it.
1150 if (JTBBs.empty()) continue;
1152 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
1153 // .set directive for each unique entry. This reduces the number of
1154 // relocations the assembler will generate for the jump table.
1155 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
1156 MAI->hasSetDirective()) {
1157 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
1158 const TargetLowering *TLI = TM.getTargetLowering();
1159 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
1160 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
1161 const MachineBasicBlock *MBB = JTBBs[ii];
1162 if (!EmittedSets.insert(MBB)) continue;
1164 // .set LJTSet, LBB32-base
1166 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1167 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
1168 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
1172 // On some targets (e.g. Darwin) we want to emit two consecutive labels
1173 // before each jump table. The first label is never referenced, but tells
1174 // the assembler and linker the extents of the jump table object. The
1175 // second label is actually referenced by the code.
1176 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
1177 // FIXME: This doesn't have to have any specific name, just any randomly
1178 // named and numbered 'l' label would work. Simplify GetJTISymbol.
1179 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
1181 OutStreamer.EmitLabel(GetJTISymbol(JTI));
1183 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
1184 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
1186 if (!JTInDiffSection)
1187 OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
1190 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
1192 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
1193 const MachineBasicBlock *MBB,
1194 unsigned UID) const {
1195 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block");
1196 const MCExpr *Value = 0;
1197 switch (MJTI->getEntryKind()) {
1198 case MachineJumpTableInfo::EK_Inline:
1199 llvm_unreachable("Cannot emit EK_Inline jump table entry");
1200 case MachineJumpTableInfo::EK_Custom32:
1201 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
1204 case MachineJumpTableInfo::EK_BlockAddress:
1205 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
1207 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1209 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
1210 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
1211 // with a relocation as gp-relative, e.g.:
1213 MCSymbol *MBBSym = MBB->getSymbol();
1214 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1218 case MachineJumpTableInfo::EK_GPRel64BlockAddress: {
1219 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded
1220 // with a relocation as gp-relative, e.g.:
1222 MCSymbol *MBBSym = MBB->getSymbol();
1223 OutStreamer.EmitGPRel64Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1227 case MachineJumpTableInfo::EK_LabelDifference32: {
1228 // EK_LabelDifference32 - Each entry is the address of the block minus
1229 // the address of the jump table. This is used for PIC jump tables where
1230 // gprel32 is not supported. e.g.:
1231 // .word LBB123 - LJTI1_2
1232 // If the .set directive is supported, this is emitted as:
1233 // .set L4_5_set_123, LBB123 - LJTI1_2
1234 // .word L4_5_set_123
1236 // If we have emitted set directives for the jump table entries, print
1237 // them rather than the entries themselves. If we're emitting PIC, then
1238 // emit the table entries as differences between two text section labels.
1239 if (MAI->hasSetDirective()) {
1240 // If we used .set, reference the .set's symbol.
1241 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
1245 // Otherwise, use the difference as the jump table entry.
1246 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1247 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
1248 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
1253 assert(Value && "Unknown entry kind!");
1255 unsigned EntrySize = MJTI->getEntrySize(*TM.getDataLayout());
1256 OutStreamer.EmitValue(Value, EntrySize);
1260 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
1261 /// special global used by LLVM. If so, emit it and return true, otherwise
1262 /// do nothing and return false.
1263 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
1264 if (GV->getName() == "llvm.used") {
1265 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
1266 EmitLLVMUsedList(cast<ConstantArray>(GV->getInitializer()));
1270 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
1271 if (GV->getSection() == "llvm.metadata" ||
1272 GV->hasAvailableExternallyLinkage())
1275 if (!GV->hasAppendingLinkage()) return false;
1277 assert(GV->hasInitializer() && "Not a special LLVM global!");
1279 if (GV->getName() == "llvm.global_ctors") {
1280 EmitXXStructorList(GV->getInitializer(), /* isCtor */ true);
1282 if (TM.getRelocationModel() == Reloc::Static &&
1283 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1284 StringRef Sym(".constructors_used");
1285 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1291 if (GV->getName() == "llvm.global_dtors") {
1292 EmitXXStructorList(GV->getInitializer(), /* isCtor */ false);
1294 if (TM.getRelocationModel() == Reloc::Static &&
1295 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1296 StringRef Sym(".destructors_used");
1297 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1306 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1307 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1308 /// is true, as being used with this directive.
1309 void AsmPrinter::EmitLLVMUsedList(const ConstantArray *InitList) {
1310 // Should be an array of 'i8*'.
1311 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1312 const GlobalValue *GV =
1313 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1314 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
1315 OutStreamer.EmitSymbolAttribute(getSymbol(GV), MCSA_NoDeadStrip);
1319 /// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
1321 void AsmPrinter::EmitXXStructorList(const Constant *List, bool isCtor) {
1322 // Should be an array of '{ int, void ()* }' structs. The first value is the
1324 if (!isa<ConstantArray>(List)) return;
1326 // Sanity check the structors list.
1327 const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1328 if (!InitList) return; // Not an array!
1329 StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType());
1330 if (!ETy || ETy->getNumElements() != 2) return; // Not an array of pairs!
1331 if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) ||
1332 !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr).
1334 // Gather the structors in a form that's convenient for sorting by priority.
1335 typedef std::pair<unsigned, Constant *> Structor;
1336 SmallVector<Structor, 8> Structors;
1337 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1338 ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i));
1339 if (!CS) continue; // Malformed.
1340 if (CS->getOperand(1)->isNullValue())
1341 break; // Found a null terminator, skip the rest.
1342 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
1343 if (!Priority) continue; // Malformed.
1344 Structors.push_back(std::make_pair(Priority->getLimitedValue(65535),
1345 CS->getOperand(1)));
1348 // Emit the function pointers in the target-specific order
1349 const DataLayout *DL = TM.getDataLayout();
1350 unsigned Align = Log2_32(DL->getPointerPrefAlignment());
1351 std::stable_sort(Structors.begin(), Structors.end(), less_first());
1352 for (unsigned i = 0, e = Structors.size(); i != e; ++i) {
1353 const MCSection *OutputSection =
1355 getObjFileLowering().getStaticCtorSection(Structors[i].first) :
1356 getObjFileLowering().getStaticDtorSection(Structors[i].first));
1357 OutStreamer.SwitchSection(OutputSection);
1358 if (OutStreamer.getCurrentSection() != OutStreamer.getPreviousSection())
1359 EmitAlignment(Align);
1360 EmitXXStructor(Structors[i].second);
1364 void AsmPrinter::EmitModuleIdents(Module &M) {
1365 if (!MAI->hasIdentDirective())
1368 if (const NamedMDNode *NMD = M.getNamedMetadata("llvm.ident")) {
1369 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
1370 const MDNode *N = NMD->getOperand(i);
1371 assert(N->getNumOperands() == 1 &&
1372 "llvm.ident metadata entry can have only one operand");
1373 const MDString *S = cast<MDString>(N->getOperand(0));
1374 OutStreamer.EmitIdent(S->getString());
1379 //===--------------------------------------------------------------------===//
1380 // Emission and print routines
1383 /// EmitInt8 - Emit a byte directive and value.
1385 void AsmPrinter::EmitInt8(int Value) const {
1386 OutStreamer.EmitIntValue(Value, 1);
1389 /// EmitInt16 - Emit a short directive and value.
1391 void AsmPrinter::EmitInt16(int Value) const {
1392 OutStreamer.EmitIntValue(Value, 2);
1395 /// EmitInt32 - Emit a long directive and value.
1397 void AsmPrinter::EmitInt32(int Value) const {
1398 OutStreamer.EmitIntValue(Value, 4);
1401 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
1402 /// in bytes of the directive is specified by Size and Hi/Lo specify the
1403 /// labels. This implicitly uses .set if it is available.
1404 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1405 unsigned Size) const {
1406 // Get the Hi-Lo expression.
1407 const MCExpr *Diff =
1408 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1409 MCSymbolRefExpr::Create(Lo, OutContext),
1412 if (!MAI->hasSetDirective()) {
1413 OutStreamer.EmitValue(Diff, Size);
1417 // Otherwise, emit with .set (aka assignment).
1418 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1419 OutStreamer.EmitAssignment(SetLabel, Diff);
1420 OutStreamer.EmitSymbolValue(SetLabel, Size);
1423 /// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo"
1424 /// where the size in bytes of the directive is specified by Size and Hi/Lo
1425 /// specify the labels. This implicitly uses .set if it is available.
1426 void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset,
1427 const MCSymbol *Lo, unsigned Size)
1430 // Emit Hi+Offset - Lo
1431 // Get the Hi+Offset expression.
1432 const MCExpr *Plus =
1433 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext),
1434 MCConstantExpr::Create(Offset, OutContext),
1437 // Get the Hi+Offset-Lo expression.
1438 const MCExpr *Diff =
1439 MCBinaryExpr::CreateSub(Plus,
1440 MCSymbolRefExpr::Create(Lo, OutContext),
1443 if (!MAI->hasSetDirective())
1444 OutStreamer.EmitValue(Diff, Size);
1446 // Otherwise, emit with .set (aka assignment).
1447 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1448 OutStreamer.EmitAssignment(SetLabel, Diff);
1449 OutStreamer.EmitSymbolValue(SetLabel, Size);
1453 /// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
1454 /// where the size in bytes of the directive is specified by Size and Label
1455 /// specifies the label. This implicitly uses .set if it is available.
1456 void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset,
1457 unsigned Size, bool IsSectionRelative)
1459 if (MAI->needsDwarfSectionOffsetDirective() && IsSectionRelative) {
1460 OutStreamer.EmitCOFFSecRel32(Label);
1464 // Emit Label+Offset (or just Label if Offset is zero)
1465 const MCExpr *Expr = MCSymbolRefExpr::Create(Label, OutContext);
1467 Expr = MCBinaryExpr::CreateAdd(Expr,
1468 MCConstantExpr::Create(Offset, OutContext),
1471 OutStreamer.EmitValue(Expr, Size);
1475 //===----------------------------------------------------------------------===//
1477 // EmitAlignment - Emit an alignment directive to the specified power of
1478 // two boundary. For example, if you pass in 3 here, you will get an 8
1479 // byte alignment. If a global value is specified, and if that global has
1480 // an explicit alignment requested, it will override the alignment request
1481 // if required for correctness.
1483 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV) const {
1484 if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getDataLayout(), NumBits);
1486 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.
1488 if (getCurrentSection()->getKind().isText())
1489 OutStreamer.EmitCodeAlignment(1 << NumBits);
1491 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
1494 //===----------------------------------------------------------------------===//
1495 // Constant emission.
1496 //===----------------------------------------------------------------------===//
1498 /// lowerConstant - Lower the specified LLVM Constant to an MCExpr.
1500 static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP) {
1501 MCContext &Ctx = AP.OutContext;
1503 if (CV->isNullValue() || isa<UndefValue>(CV))
1504 return MCConstantExpr::Create(0, Ctx);
1506 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1507 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1509 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1510 return MCSymbolRefExpr::Create(AP.getSymbol(GV), Ctx);
1512 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1513 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1515 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1517 llvm_unreachable("Unknown constant value to lower!");
1520 switch (CE->getOpcode()) {
1522 // If the code isn't optimized, there may be outstanding folding
1523 // opportunities. Attempt to fold the expression using DataLayout as a
1524 // last resort before giving up.
1526 ConstantFoldConstantExpression(CE, AP.TM.getDataLayout()))
1528 return lowerConstant(C, AP);
1530 // Otherwise report the problem to the user.
1533 raw_string_ostream OS(S);
1534 OS << "Unsupported expression in static initializer: ";
1535 WriteAsOperand(OS, CE, /*PrintType=*/false,
1536 !AP.MF ? 0 : AP.MF->getFunction()->getParent());
1537 report_fatal_error(OS.str());
1539 case Instruction::GetElementPtr: {
1540 const DataLayout &DL = *AP.TM.getDataLayout();
1541 // Generate a symbolic expression for the byte address
1542 APInt OffsetAI(DL.getPointerTypeSizeInBits(CE->getType()), 0);
1543 cast<GEPOperator>(CE)->accumulateConstantOffset(DL, OffsetAI);
1545 const MCExpr *Base = lowerConstant(CE->getOperand(0), AP);
1549 int64_t Offset = OffsetAI.getSExtValue();
1550 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1554 case Instruction::Trunc:
1555 // We emit the value and depend on the assembler to truncate the generated
1556 // expression properly. This is important for differences between
1557 // blockaddress labels. Since the two labels are in the same function, it
1558 // is reasonable to treat their delta as a 32-bit value.
1560 case Instruction::BitCast:
1561 return lowerConstant(CE->getOperand(0), AP);
1563 case Instruction::IntToPtr: {
1564 const DataLayout &DL = *AP.TM.getDataLayout();
1565 // Handle casts to pointers by changing them into casts to the appropriate
1566 // integer type. This promotes constant folding and simplifies this code.
1567 Constant *Op = CE->getOperand(0);
1568 Op = ConstantExpr::getIntegerCast(Op, DL.getIntPtrType(CV->getType()),
1570 return lowerConstant(Op, AP);
1573 case Instruction::PtrToInt: {
1574 const DataLayout &DL = *AP.TM.getDataLayout();
1575 // Support only foldable casts to/from pointers that can be eliminated by
1576 // changing the pointer to the appropriately sized integer type.
1577 Constant *Op = CE->getOperand(0);
1578 Type *Ty = CE->getType();
1580 const MCExpr *OpExpr = lowerConstant(Op, AP);
1582 // We can emit the pointer value into this slot if the slot is an
1583 // integer slot equal to the size of the pointer.
1584 if (DL.getTypeAllocSize(Ty) == DL.getTypeAllocSize(Op->getType()))
1587 // Otherwise the pointer is smaller than the resultant integer, mask off
1588 // the high bits so we are sure to get a proper truncation if the input is
1590 unsigned InBits = DL.getTypeAllocSizeInBits(Op->getType());
1591 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1592 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1595 // The MC library also has a right-shift operator, but it isn't consistently
1596 // signed or unsigned between different targets.
1597 case Instruction::Add:
1598 case Instruction::Sub:
1599 case Instruction::Mul:
1600 case Instruction::SDiv:
1601 case Instruction::SRem:
1602 case Instruction::Shl:
1603 case Instruction::And:
1604 case Instruction::Or:
1605 case Instruction::Xor: {
1606 const MCExpr *LHS = lowerConstant(CE->getOperand(0), AP);
1607 const MCExpr *RHS = lowerConstant(CE->getOperand(1), AP);
1608 switch (CE->getOpcode()) {
1609 default: llvm_unreachable("Unknown binary operator constant cast expr");
1610 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1611 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1612 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1613 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1614 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1615 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1616 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1617 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1618 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1624 static void emitGlobalConstantImpl(const Constant *C, AsmPrinter &AP);
1626 /// isRepeatedByteSequence - Determine whether the given value is
1627 /// composed of a repeated sequence of identical bytes and return the
1628 /// byte value. If it is not a repeated sequence, return -1.
1629 static int isRepeatedByteSequence(const ConstantDataSequential *V) {
1630 StringRef Data = V->getRawDataValues();
1631 assert(!Data.empty() && "Empty aggregates should be CAZ node");
1633 for (unsigned i = 1, e = Data.size(); i != e; ++i)
1634 if (Data[i] != C) return -1;
1635 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1.
1639 /// isRepeatedByteSequence - Determine whether the given value is
1640 /// composed of a repeated sequence of identical bytes and return the
1641 /// byte value. If it is not a repeated sequence, return -1.
1642 static int isRepeatedByteSequence(const Value *V, TargetMachine &TM) {
1644 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
1645 if (CI->getBitWidth() > 64) return -1;
1647 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(V->getType());
1648 uint64_t Value = CI->getZExtValue();
1650 // Make sure the constant is at least 8 bits long and has a power
1651 // of 2 bit width. This guarantees the constant bit width is
1652 // always a multiple of 8 bits, avoiding issues with padding out
1653 // to Size and other such corner cases.
1654 if (CI->getBitWidth() < 8 || !isPowerOf2_64(CI->getBitWidth())) return -1;
1656 uint8_t Byte = static_cast<uint8_t>(Value);
1658 for (unsigned i = 1; i < Size; ++i) {
1660 if (static_cast<uint8_t>(Value) != Byte) return -1;
1664 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) {
1665 // Make sure all array elements are sequences of the same repeated
1667 assert(CA->getNumOperands() != 0 && "Should be a CAZ");
1668 int Byte = isRepeatedByteSequence(CA->getOperand(0), TM);
1669 if (Byte == -1) return -1;
1671 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i) {
1672 int ThisByte = isRepeatedByteSequence(CA->getOperand(i), TM);
1673 if (ThisByte == -1) return -1;
1674 if (Byte != ThisByte) return -1;
1679 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V))
1680 return isRepeatedByteSequence(CDS);
1685 static void emitGlobalConstantDataSequential(const ConstantDataSequential *CDS,
1688 // See if we can aggregate this into a .fill, if so, emit it as such.
1689 int Value = isRepeatedByteSequence(CDS, AP.TM);
1691 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CDS->getType());
1692 // Don't emit a 1-byte object as a .fill.
1694 return AP.OutStreamer.EmitFill(Bytes, Value);
1697 // If this can be emitted with .ascii/.asciz, emit it as such.
1698 if (CDS->isString())
1699 return AP.OutStreamer.EmitBytes(CDS->getAsString());
1701 // Otherwise, emit the values in successive locations.
1702 unsigned ElementByteSize = CDS->getElementByteSize();
1703 if (isa<IntegerType>(CDS->getElementType())) {
1704 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1706 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1707 CDS->getElementAsInteger(i));
1708 AP.OutStreamer.EmitIntValue(CDS->getElementAsInteger(i),
1711 } else if (ElementByteSize == 4) {
1712 // FP Constants are printed as integer constants to avoid losing
1714 assert(CDS->getElementType()->isFloatTy());
1715 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1721 F = CDS->getElementAsFloat(i);
1723 AP.OutStreamer.GetCommentOS() << "float " << F << '\n';
1724 AP.OutStreamer.EmitIntValue(I, 4);
1727 assert(CDS->getElementType()->isDoubleTy());
1728 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1734 F = CDS->getElementAsDouble(i);
1736 AP.OutStreamer.GetCommentOS() << "double " << F << '\n';
1737 AP.OutStreamer.EmitIntValue(I, 8);
1741 const DataLayout &DL = *AP.TM.getDataLayout();
1742 unsigned Size = DL.getTypeAllocSize(CDS->getType());
1743 unsigned EmittedSize = DL.getTypeAllocSize(CDS->getType()->getElementType()) *
1744 CDS->getNumElements();
1745 if (unsigned Padding = Size - EmittedSize)
1746 AP.OutStreamer.EmitZeros(Padding);
1750 static void emitGlobalConstantArray(const ConstantArray *CA, AsmPrinter &AP) {
1751 // See if we can aggregate some values. Make sure it can be
1752 // represented as a series of bytes of the constant value.
1753 int Value = isRepeatedByteSequence(CA, AP.TM);
1756 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CA->getType());
1757 AP.OutStreamer.EmitFill(Bytes, Value);
1760 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1761 emitGlobalConstantImpl(CA->getOperand(i), AP);
1765 static void emitGlobalConstantVector(const ConstantVector *CV, AsmPrinter &AP) {
1766 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1767 emitGlobalConstantImpl(CV->getOperand(i), AP);
1769 const DataLayout &DL = *AP.TM.getDataLayout();
1770 unsigned Size = DL.getTypeAllocSize(CV->getType());
1771 unsigned EmittedSize = DL.getTypeAllocSize(CV->getType()->getElementType()) *
1772 CV->getType()->getNumElements();
1773 if (unsigned Padding = Size - EmittedSize)
1774 AP.OutStreamer.EmitZeros(Padding);
1777 static void emitGlobalConstantStruct(const ConstantStruct *CS, AsmPrinter &AP) {
1778 // Print the fields in successive locations. Pad to align if needed!
1779 const DataLayout *DL = AP.TM.getDataLayout();
1780 unsigned Size = DL->getTypeAllocSize(CS->getType());
1781 const StructLayout *Layout = DL->getStructLayout(CS->getType());
1782 uint64_t SizeSoFar = 0;
1783 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1784 const Constant *Field = CS->getOperand(i);
1786 // Check if padding is needed and insert one or more 0s.
1787 uint64_t FieldSize = DL->getTypeAllocSize(Field->getType());
1788 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1789 - Layout->getElementOffset(i)) - FieldSize;
1790 SizeSoFar += FieldSize + PadSize;
1792 // Now print the actual field value.
1793 emitGlobalConstantImpl(Field, AP);
1795 // Insert padding - this may include padding to increase the size of the
1796 // current field up to the ABI size (if the struct is not packed) as well
1797 // as padding to ensure that the next field starts at the right offset.
1798 AP.OutStreamer.EmitZeros(PadSize);
1800 assert(SizeSoFar == Layout->getSizeInBytes() &&
1801 "Layout of constant struct may be incorrect!");
1804 static void emitGlobalConstantFP(const ConstantFP *CFP, AsmPrinter &AP) {
1805 APInt API = CFP->getValueAPF().bitcastToAPInt();
1807 // First print a comment with what we think the original floating-point value
1808 // should have been.
1809 if (AP.isVerbose()) {
1810 SmallString<8> StrVal;
1811 CFP->getValueAPF().toString(StrVal);
1813 CFP->getType()->print(AP.OutStreamer.GetCommentOS());
1814 AP.OutStreamer.GetCommentOS() << ' ' << StrVal << '\n';
1817 // Now iterate through the APInt chunks, emitting them in endian-correct
1818 // order, possibly with a smaller chunk at beginning/end (e.g. for x87 80-bit
1820 unsigned NumBytes = API.getBitWidth() / 8;
1821 unsigned TrailingBytes = NumBytes % sizeof(uint64_t);
1822 const uint64_t *p = API.getRawData();
1824 // PPC's long double has odd notions of endianness compared to how LLVM
1825 // handles it: p[0] goes first for *big* endian on PPC.
1826 if (AP.TM.getDataLayout()->isBigEndian() != CFP->getType()->isPPC_FP128Ty()) {
1827 int Chunk = API.getNumWords() - 1;
1830 AP.OutStreamer.EmitIntValue(p[Chunk--], TrailingBytes);
1832 for (; Chunk >= 0; --Chunk)
1833 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1836 for (Chunk = 0; Chunk < NumBytes / sizeof(uint64_t); ++Chunk)
1837 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1840 AP.OutStreamer.EmitIntValue(p[Chunk], TrailingBytes);
1843 // Emit the tail padding for the long double.
1844 const DataLayout &DL = *AP.TM.getDataLayout();
1845 AP.OutStreamer.EmitZeros(DL.getTypeAllocSize(CFP->getType()) -
1846 DL.getTypeStoreSize(CFP->getType()));
1849 static void emitGlobalConstantLargeInt(const ConstantInt *CI, AsmPrinter &AP) {
1850 const DataLayout *DL = AP.TM.getDataLayout();
1851 unsigned BitWidth = CI->getBitWidth();
1853 // Copy the value as we may massage the layout for constants whose bit width
1854 // is not a multiple of 64-bits.
1855 APInt Realigned(CI->getValue());
1856 uint64_t ExtraBits = 0;
1857 unsigned ExtraBitsSize = BitWidth & 63;
1859 if (ExtraBitsSize) {
1860 // The bit width of the data is not a multiple of 64-bits.
1861 // The extra bits are expected to be at the end of the chunk of the memory.
1863 // * Nothing to be done, just record the extra bits to emit.
1865 // * Record the extra bits to emit.
1866 // * Realign the raw data to emit the chunks of 64-bits.
1867 if (DL->isBigEndian()) {
1868 // Basically the structure of the raw data is a chunk of 64-bits cells:
1869 // 0 1 BitWidth / 64
1870 // [chunk1][chunk2] ... [chunkN].
1871 // The most significant chunk is chunkN and it should be emitted first.
1872 // However, due to the alignment issue chunkN contains useless bits.
1873 // Realign the chunks so that they contain only useless information:
1874 // ExtraBits 0 1 (BitWidth / 64) - 1
1875 // chu[nk1 chu][nk2 chu] ... [nkN-1 chunkN]
1876 ExtraBits = Realigned.getRawData()[0] &
1877 (((uint64_t)-1) >> (64 - ExtraBitsSize));
1878 Realigned = Realigned.lshr(ExtraBitsSize);
1880 ExtraBits = Realigned.getRawData()[BitWidth / 64];
1883 // We don't expect assemblers to support integer data directives
1884 // for more than 64 bits, so we emit the data in at most 64-bit
1885 // quantities at a time.
1886 const uint64_t *RawData = Realigned.getRawData();
1887 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1888 uint64_t Val = DL->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1889 AP.OutStreamer.EmitIntValue(Val, 8);
1892 if (ExtraBitsSize) {
1893 // Emit the extra bits after the 64-bits chunks.
1895 // Emit a directive that fills the expected size.
1896 uint64_t Size = AP.TM.getDataLayout()->getTypeAllocSize(CI->getType());
1897 Size -= (BitWidth / 64) * 8;
1898 assert(Size && Size * 8 >= ExtraBitsSize &&
1899 (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize)))
1900 == ExtraBits && "Directive too small for extra bits.");
1901 AP.OutStreamer.EmitIntValue(ExtraBits, Size);
1905 static void emitGlobalConstantImpl(const Constant *CV, AsmPrinter &AP) {
1906 const DataLayout *DL = AP.TM.getDataLayout();
1907 uint64_t Size = DL->getTypeAllocSize(CV->getType());
1908 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV))
1909 return AP.OutStreamer.EmitZeros(Size);
1911 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1918 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1919 CI->getZExtValue());
1920 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size);
1923 emitGlobalConstantLargeInt(CI, AP);
1928 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1929 return emitGlobalConstantFP(CFP, AP);
1931 if (isa<ConstantPointerNull>(CV)) {
1932 AP.OutStreamer.EmitIntValue(0, Size);
1936 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV))
1937 return emitGlobalConstantDataSequential(CDS, AP);
1939 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1940 return emitGlobalConstantArray(CVA, AP);
1942 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1943 return emitGlobalConstantStruct(CVS, AP);
1945 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
1946 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
1948 if (CE->getOpcode() == Instruction::BitCast)
1949 return emitGlobalConstantImpl(CE->getOperand(0), AP);
1952 // If the constant expression's size is greater than 64-bits, then we have
1953 // to emit the value in chunks. Try to constant fold the value and emit it
1955 Constant *New = ConstantFoldConstantExpression(CE, DL);
1956 if (New && New != CE)
1957 return emitGlobalConstantImpl(New, AP);
1961 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1962 return emitGlobalConstantVector(V, AP);
1964 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1965 // thread the streamer with EmitValue.
1966 AP.OutStreamer.EmitValue(lowerConstant(CV, AP), Size);
1969 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1970 void AsmPrinter::EmitGlobalConstant(const Constant *CV) {
1971 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(CV->getType());
1973 emitGlobalConstantImpl(CV, *this);
1974 else if (MAI->hasSubsectionsViaSymbols()) {
1975 // If the global has zero size, emit a single byte so that two labels don't
1976 // look like they are at the same location.
1977 OutStreamer.EmitIntValue(0, 1);
1981 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1982 // Target doesn't support this yet!
1983 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1986 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1988 OS << '+' << Offset;
1989 else if (Offset < 0)
1993 //===----------------------------------------------------------------------===//
1994 // Symbol Lowering Routines.
1995 //===----------------------------------------------------------------------===//
1997 /// GetTempSymbol - Return the MCSymbol corresponding to the assembler
1998 /// temporary label with the specified stem and unique ID.
1999 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const {
2000 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) +
2004 /// GetTempSymbol - Return an assembler temporary label with the specified
2006 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const {
2007 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix())+
2012 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
2013 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
2016 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
2017 return MMI->getAddrLabelSymbol(BB);
2020 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
2021 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
2022 return OutContext.GetOrCreateSymbol
2023 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
2024 + "_" + Twine(CPID));
2027 /// GetJTISymbol - Return the symbol for the specified jump table entry.
2028 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
2029 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
2032 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
2033 /// FIXME: privatize to AsmPrinter.
2034 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
2035 return OutContext.GetOrCreateSymbol
2036 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
2037 Twine(UID) + "_set_" + Twine(MBBID));
2040 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
2041 /// global value name as its base, with the specified suffix, and where the
2042 /// symbol is forced to have private linkage if ForcePrivate is true.
2043 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
2045 bool ForcePrivate) const {
2046 SmallString<60> NameStr;
2047 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
2048 NameStr.append(Suffix.begin(), Suffix.end());
2049 return OutContext.GetOrCreateSymbol(NameStr.str());
2052 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
2054 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
2055 SmallString<60> NameStr;
2056 Mang->getNameWithPrefix(NameStr, Sym);
2057 return OutContext.GetOrCreateSymbol(NameStr.str());
2062 /// PrintParentLoopComment - Print comments about parent loops of this one.
2063 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2064 unsigned FunctionNumber) {
2065 if (Loop == 0) return;
2066 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
2067 OS.indent(Loop->getLoopDepth()*2)
2068 << "Parent Loop BB" << FunctionNumber << "_"
2069 << Loop->getHeader()->getNumber()
2070 << " Depth=" << Loop->getLoopDepth() << '\n';
2074 /// PrintChildLoopComment - Print comments about child loops within
2075 /// the loop for this basic block, with nesting.
2076 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2077 unsigned FunctionNumber) {
2078 // Add child loop information
2079 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
2080 OS.indent((*CL)->getLoopDepth()*2)
2081 << "Child Loop BB" << FunctionNumber << "_"
2082 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
2084 PrintChildLoopComment(OS, *CL, FunctionNumber);
2088 /// emitBasicBlockLoopComments - Pretty-print comments for basic blocks.
2089 static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
2090 const MachineLoopInfo *LI,
2091 const AsmPrinter &AP) {
2092 // Add loop depth information
2093 const MachineLoop *Loop = LI->getLoopFor(&MBB);
2094 if (Loop == 0) return;
2096 MachineBasicBlock *Header = Loop->getHeader();
2097 assert(Header && "No header for loop");
2099 // If this block is not a loop header, just print out what is the loop header
2101 if (Header != &MBB) {
2102 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
2103 Twine(AP.getFunctionNumber())+"_" +
2104 Twine(Loop->getHeader()->getNumber())+
2105 " Depth="+Twine(Loop->getLoopDepth()));
2109 // Otherwise, it is a loop header. Print out information about child and
2111 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
2113 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
2116 OS.indent(Loop->getLoopDepth()*2-2);
2121 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
2123 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
2127 /// EmitBasicBlockStart - This method prints the label for the specified
2128 /// MachineBasicBlock, an alignment (if present) and a comment describing
2129 /// it if appropriate.
2130 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
2131 // Emit an alignment directive for this block, if needed.
2132 if (unsigned Align = MBB->getAlignment())
2133 EmitAlignment(Align);
2135 // If the block has its address taken, emit any labels that were used to
2136 // reference the block. It is possible that there is more than one label
2137 // here, because multiple LLVM BB's may have been RAUW'd to this block after
2138 // the references were generated.
2139 if (MBB->hasAddressTaken()) {
2140 const BasicBlock *BB = MBB->getBasicBlock();
2142 OutStreamer.AddComment("Block address taken");
2144 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
2146 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
2147 OutStreamer.EmitLabel(Syms[i]);
2150 // Print some verbose block comments.
2152 if (const BasicBlock *BB = MBB->getBasicBlock())
2154 OutStreamer.AddComment("%" + BB->getName());
2155 emitBasicBlockLoopComments(*MBB, LI, *this);
2158 // Print the main label for the block.
2159 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
2160 if (isVerbose() && OutStreamer.hasRawTextSupport()) {
2161 // NOTE: Want this comment at start of line, don't emit with AddComment.
2162 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" +
2163 Twine(MBB->getNumber()) + ":");
2166 OutStreamer.EmitLabel(MBB->getSymbol());
2170 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility,
2171 bool IsDefinition) const {
2172 MCSymbolAttr Attr = MCSA_Invalid;
2174 switch (Visibility) {
2176 case GlobalValue::HiddenVisibility:
2178 Attr = MAI->getHiddenVisibilityAttr();
2180 Attr = MAI->getHiddenDeclarationVisibilityAttr();
2182 case GlobalValue::ProtectedVisibility:
2183 Attr = MAI->getProtectedVisibilityAttr();
2187 if (Attr != MCSA_Invalid)
2188 OutStreamer.EmitSymbolAttribute(Sym, Attr);
2191 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
2192 /// exactly one predecessor and the control transfer mechanism between
2193 /// the predecessor and this block is a fall-through.
2195 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
2196 // If this is a landing pad, it isn't a fall through. If it has no preds,
2197 // then nothing falls through to it.
2198 if (MBB->isLandingPad() || MBB->pred_empty())
2201 // If there isn't exactly one predecessor, it can't be a fall through.
2202 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
2204 if (PI2 != MBB->pred_end())
2207 // The predecessor has to be immediately before this block.
2208 MachineBasicBlock *Pred = *PI;
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 (MachineBasicBlock::iterator II = Pred->getFirstTerminator(),
2219 IE = Pred->end(); II != IE; ++II) {
2220 MachineInstr &MI = *II;
2222 // If it is not a simple branch, we are in a table somewhere.
2223 if (!MI.isBranch() || MI.isIndirectBranch())
2226 // If we are the operands of one of the branches, this is not a fall
2227 // through. Note that targets with delay slots will usually bundle
2228 // terminators with the delay slot instruction.
2229 for (ConstMIBundleOperands OP(&MI); OP.isValid(); ++OP) {
2232 if (OP->isMBB() && OP->getMBB() == MBB)
2242 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
2243 if (!S->usesMetadata())
2246 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
2247 gcp_map_type::iterator GCPI = GCMap.find(S);
2248 if (GCPI != GCMap.end())
2249 return GCPI->second;
2251 const char *Name = S->getName().c_str();
2253 for (GCMetadataPrinterRegistry::iterator
2254 I = GCMetadataPrinterRegistry::begin(),
2255 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
2256 if (strcmp(Name, I->getName()) == 0) {
2257 GCMetadataPrinter *GMP = I->instantiate();
2259 GCMap.insert(std::make_pair(S, GMP));
2263 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));