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 "WinCodeViewLineTables.h"
19 #include "llvm/ADT/SmallString.h"
20 #include "llvm/ADT/Statistic.h"
21 #include "llvm/Analysis/ConstantFolding.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/IR/DataLayout.h"
31 #include "llvm/IR/DebugInfo.h"
32 #include "llvm/IR/Mangler.h"
33 #include "llvm/IR/Module.h"
34 #include "llvm/IR/Operator.h"
35 #include "llvm/MC/MCAsmInfo.h"
36 #include "llvm/MC/MCContext.h"
37 #include "llvm/MC/MCExpr.h"
38 #include "llvm/MC/MCInst.h"
39 #include "llvm/MC/MCSection.h"
40 #include "llvm/MC/MCStreamer.h"
41 #include "llvm/MC/MCSymbol.h"
42 #include "llvm/Support/ErrorHandling.h"
43 #include "llvm/Support/Format.h"
44 #include "llvm/Support/MathExtras.h"
45 #include "llvm/Support/Timer.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/Target/TargetSubtargetInfo.h"
53 #include "llvm/Transforms/Utils/GlobalStatus.h"
56 static const char *const DWARFGroupName = "DWARF Emission";
57 static const char *const DbgTimerName = "Debug Info Emission";
58 static const char *const EHTimerName = "DWARF Exception Writer";
59 static const char *const CodeViewLineTablesGroupName = "CodeView Line Tables";
61 STATISTIC(EmittedInsts, "Number of machine instrs printed");
63 char AsmPrinter::ID = 0;
65 typedef DenseMap<GCStrategy*,GCMetadataPrinter*> gcp_map_type;
66 static gcp_map_type &getGCMap(void *&P) {
68 P = new gcp_map_type();
69 return *(gcp_map_type*)P;
73 /// getGVAlignmentLog2 - Return the alignment to use for the specified global
74 /// value in log2 form. This rounds up to the preferred alignment if possible
76 static unsigned getGVAlignmentLog2(const GlobalValue *GV, const DataLayout &TD,
77 unsigned InBits = 0) {
79 if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV))
80 NumBits = TD.getPreferredAlignmentLog(GVar);
82 // If InBits is specified, round it to it.
86 // If the GV has a specified alignment, take it into account.
87 if (GV->getAlignment() == 0)
90 unsigned GVAlign = Log2_32(GV->getAlignment());
92 // If the GVAlign is larger than NumBits, or if we are required to obey
93 // NumBits because the GV has an assigned section, obey it.
94 if (GVAlign > NumBits || GV->hasSection())
99 AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
100 : MachineFunctionPass(ID),
101 TM(tm), MAI(tm.getMCAsmInfo()), MII(tm.getInstrInfo()),
102 OutContext(Streamer.getContext()),
103 OutStreamer(Streamer),
104 LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {
105 DD = 0; MMI = 0; LI = 0; MF = 0;
106 CurrentFnSym = CurrentFnSymForSize = 0;
107 GCMetadataPrinters = 0;
108 VerboseAsm = Streamer.isVerboseAsm();
111 AsmPrinter::~AsmPrinter() {
112 assert(DD == 0 && Handlers.empty() && "Debug/EH info didn't get finalized");
114 if (GCMetadataPrinters != 0) {
115 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
117 for (gcp_map_type::iterator I = GCMap.begin(), E = GCMap.end(); I != E; ++I)
120 GCMetadataPrinters = 0;
126 /// getFunctionNumber - Return a unique ID for the current function.
128 unsigned AsmPrinter::getFunctionNumber() const {
129 return MF->getFunctionNumber();
132 const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
133 return TM.getTargetLowering()->getObjFileLowering();
136 /// getDataLayout - Return information about data layout.
137 const DataLayout &AsmPrinter::getDataLayout() const {
138 return *TM.getDataLayout();
141 const MCSubtargetInfo &AsmPrinter::getSubtargetInfo() const {
142 return TM.getSubtarget<MCSubtargetInfo>();
145 void AsmPrinter::EmitToStreamer(MCStreamer &S, const MCInst &Inst) {
146 S.EmitInstruction(Inst, getSubtargetInfo());
149 StringRef AsmPrinter::getTargetTriple() const {
150 return TM.getTargetTriple();
153 /// getCurrentSection() - Return the current section we are emitting to.
154 const MCSection *AsmPrinter::getCurrentSection() const {
155 return OutStreamer.getCurrentSection().first;
160 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
161 AU.setPreservesAll();
162 MachineFunctionPass::getAnalysisUsage(AU);
163 AU.addRequired<MachineModuleInfo>();
164 AU.addRequired<GCModuleInfo>();
166 AU.addRequired<MachineLoopInfo>();
169 bool AsmPrinter::doInitialization(Module &M) {
170 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
171 MMI->AnalyzeModule(M);
173 // Initialize TargetLoweringObjectFile.
174 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
175 .Initialize(OutContext, TM);
177 OutStreamer.InitSections();
179 Mang = new Mangler(TM.getDataLayout());
181 // Allow the target to emit any magic that it wants at the start of the file.
182 EmitStartOfAsmFile(M);
184 // Very minimal debug info. It is ignored if we emit actual debug info. If we
185 // don't, this at least helps the user find where a global came from.
186 if (MAI->hasSingleParameterDotFile()) {
188 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
191 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
192 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
193 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
194 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
195 MP->beginAssembly(*this);
197 // Emit module-level inline asm if it exists.
198 if (!M.getModuleInlineAsm().empty()) {
199 OutStreamer.AddComment("Start of file scope inline assembly");
200 OutStreamer.AddBlankLine();
201 EmitInlineAsm(M.getModuleInlineAsm()+"\n");
202 OutStreamer.AddComment("End of file scope inline assembly");
203 OutStreamer.AddBlankLine();
206 if (MAI->doesSupportDebugInformation()) {
207 if (Triple(TM.getTargetTriple()).getOS() == Triple::Win32) {
208 Handlers.push_back(HandlerInfo(new WinCodeViewLineTables(this),
210 CodeViewLineTablesGroupName));
212 DD = new DwarfDebug(this, &M);
213 Handlers.push_back(HandlerInfo(DD, DbgTimerName, DWARFGroupName));
217 DwarfException *DE = 0;
218 switch (MAI->getExceptionHandlingType()) {
219 case ExceptionHandling::None:
221 case ExceptionHandling::SjLj:
222 case ExceptionHandling::DwarfCFI:
223 DE = new DwarfCFIException(this);
225 case ExceptionHandling::ARM:
226 DE = new ARMException(this);
228 case ExceptionHandling::Win64:
229 DE = new Win64Exception(this);
233 Handlers.push_back(HandlerInfo(DE, EHTimerName, DWARFGroupName));
237 static bool canBeHidden(const GlobalValue *GV, const MCAsmInfo &MAI) {
238 GlobalValue::LinkageTypes Linkage = GV->getLinkage();
239 if (Linkage != GlobalValue::LinkOnceODRLinkage)
242 if (!MAI.hasWeakDefCanBeHiddenDirective())
245 if (GV->hasUnnamedAddr())
248 // This is only used for MachO, so right now it doesn't really matter how
249 // we handle alias. Revisit this once the MachO linker implements aliases.
250 if (isa<GlobalAlias>(GV))
253 // If it is a non constant variable, it needs to be uniqued across shared
255 if (const GlobalVariable *Var = dyn_cast<GlobalVariable>(GV)) {
256 if (!Var->isConstant())
261 if (!GlobalStatus::analyzeGlobal(GV, GS) && !GS.IsCompared)
267 void AsmPrinter::EmitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const {
268 GlobalValue::LinkageTypes Linkage = GV->getLinkage();
270 case GlobalValue::CommonLinkage:
271 case GlobalValue::LinkOnceAnyLinkage:
272 case GlobalValue::LinkOnceODRLinkage:
273 case GlobalValue::WeakAnyLinkage:
274 case GlobalValue::WeakODRLinkage:
275 if (MAI->hasWeakDefDirective()) {
277 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
279 if (!canBeHidden(GV, *MAI))
280 // .weak_definition _foo
281 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
283 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefAutoPrivate);
284 } else if (MAI->hasLinkOnceDirective()) {
286 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
287 //NOTE: linkonce is handled by the section the symbol was assigned to.
290 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
293 case GlobalValue::AppendingLinkage:
294 // FIXME: appending linkage variables should go into a section of
295 // their name or something. For now, just emit them as external.
296 case GlobalValue::ExternalLinkage:
297 // If external or appending, declare as a global symbol.
299 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
301 case GlobalValue::PrivateLinkage:
302 case GlobalValue::InternalLinkage:
304 case GlobalValue::AvailableExternallyLinkage:
305 llvm_unreachable("Should never emit this");
306 case GlobalValue::ExternalWeakLinkage:
307 llvm_unreachable("Don't know how to emit these");
309 llvm_unreachable("Unknown linkage type!");
312 void AsmPrinter::getNameWithPrefix(SmallVectorImpl<char> &Name,
313 const GlobalValue *GV) const {
314 TM.getNameWithPrefix(Name, GV, *Mang);
317 MCSymbol *AsmPrinter::getSymbol(const GlobalValue *GV) const {
318 return TM.getSymbol(GV, *Mang);
321 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
322 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
323 if (GV->hasInitializer()) {
324 // Check to see if this is a special global used by LLVM, if so, emit it.
325 if (EmitSpecialLLVMGlobal(GV))
329 GV->printAsOperand(OutStreamer.GetCommentOS(),
330 /*PrintType=*/false, GV->getParent());
331 OutStreamer.GetCommentOS() << '\n';
335 MCSymbol *GVSym = getSymbol(GV);
336 EmitVisibility(GVSym, GV->getVisibility(), !GV->isDeclaration());
338 if (!GV->hasInitializer()) // External globals require no extra code.
341 if (MAI->hasDotTypeDotSizeDirective())
342 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
344 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
346 const DataLayout *DL = TM.getDataLayout();
347 uint64_t Size = DL->getTypeAllocSize(GV->getType()->getElementType());
349 // If the alignment is specified, we *must* obey it. Overaligning a global
350 // with a specified alignment is a prompt way to break globals emitted to
351 // sections and expected to be contiguous (e.g. ObjC metadata).
352 unsigned AlignLog = getGVAlignmentLog2(GV, *DL);
354 for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
355 const HandlerInfo &OI = Handlers[I];
356 NamedRegionTimer T(OI.TimerName, OI.TimerGroupName, TimePassesIsEnabled);
357 OI.Handler->setSymbolSize(GVSym, Size);
360 // Handle common and BSS local symbols (.lcomm).
361 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
362 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
363 unsigned Align = 1 << AlignLog;
365 // Handle common symbols.
366 if (GVKind.isCommon()) {
367 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
371 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
375 // Handle local BSS symbols.
376 if (MAI->hasMachoZeroFillDirective()) {
377 const MCSection *TheSection =
378 getObjFileLowering().SectionForGlobal(GV, GVKind, *Mang, TM);
379 // .zerofill __DATA, __bss, _foo, 400, 5
380 OutStreamer.EmitZerofill(TheSection, GVSym, Size, Align);
384 // Use .lcomm only if it supports user-specified alignment.
385 // Otherwise, while it would still be correct to use .lcomm in some
386 // cases (e.g. when Align == 1), the external assembler might enfore
387 // some -unknown- default alignment behavior, which could cause
388 // spurious differences between external and integrated assembler.
389 // Prefer to simply fall back to .local / .comm in this case.
390 if (MAI->getLCOMMDirectiveAlignmentType() != LCOMM::NoAlignment) {
392 OutStreamer.EmitLocalCommonSymbol(GVSym, Size, Align);
396 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
400 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
402 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
406 const MCSection *TheSection =
407 getObjFileLowering().SectionForGlobal(GV, GVKind, *Mang, TM);
409 // Handle the zerofill directive on darwin, which is a special form of BSS
411 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
412 if (Size == 0) Size = 1; // zerofill of 0 bytes is undefined.
415 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
416 // .zerofill __DATA, __common, _foo, 400, 5
417 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
421 // Handle thread local data for mach-o which requires us to output an
422 // additional structure of data and mangle the original symbol so that we
423 // can reference it later.
425 // TODO: This should become an "emit thread local global" method on TLOF.
426 // All of this macho specific stuff should be sunk down into TLOFMachO and
427 // stuff like "TLSExtraDataSection" should no longer be part of the parent
428 // TLOF class. This will also make it more obvious that stuff like
429 // MCStreamer::EmitTBSSSymbol is macho specific and only called from macho
431 if (GVKind.isThreadLocal() && MAI->hasMachoTBSSDirective()) {
432 // Emit the .tbss symbol
434 OutContext.GetOrCreateSymbol(GVSym->getName() + Twine("$tlv$init"));
436 if (GVKind.isThreadBSS()) {
437 TheSection = getObjFileLowering().getTLSBSSSection();
438 OutStreamer.EmitTBSSSymbol(TheSection, MangSym, Size, 1 << AlignLog);
439 } else if (GVKind.isThreadData()) {
440 OutStreamer.SwitchSection(TheSection);
442 EmitAlignment(AlignLog, GV);
443 OutStreamer.EmitLabel(MangSym);
445 EmitGlobalConstant(GV->getInitializer());
448 OutStreamer.AddBlankLine();
450 // Emit the variable struct for the runtime.
451 const MCSection *TLVSect
452 = getObjFileLowering().getTLSExtraDataSection();
454 OutStreamer.SwitchSection(TLVSect);
455 // Emit the linkage here.
456 EmitLinkage(GV, GVSym);
457 OutStreamer.EmitLabel(GVSym);
459 // Three pointers in size:
460 // - __tlv_bootstrap - used to make sure support exists
461 // - spare pointer, used when mapped by the runtime
462 // - pointer to mangled symbol above with initializer
463 unsigned PtrSize = DL->getPointerTypeSize(GV->getType());
464 OutStreamer.EmitSymbolValue(GetExternalSymbolSymbol("_tlv_bootstrap"),
466 OutStreamer.EmitIntValue(0, PtrSize);
467 OutStreamer.EmitSymbolValue(MangSym, PtrSize);
469 OutStreamer.AddBlankLine();
473 OutStreamer.SwitchSection(TheSection);
475 EmitLinkage(GV, GVSym);
476 EmitAlignment(AlignLog, GV);
478 OutStreamer.EmitLabel(GVSym);
480 EmitGlobalConstant(GV->getInitializer());
482 if (MAI->hasDotTypeDotSizeDirective())
484 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
486 OutStreamer.AddBlankLine();
489 /// EmitFunctionHeader - This method emits the header for the current
491 void AsmPrinter::EmitFunctionHeader() {
492 // Print out constants referenced by the function
495 // Print the 'header' of function.
496 const Function *F = MF->getFunction();
498 OutStreamer.SwitchSection(
499 getObjFileLowering().SectionForGlobal(F, *Mang, TM));
500 EmitVisibility(CurrentFnSym, F->getVisibility());
502 EmitLinkage(F, CurrentFnSym);
503 EmitAlignment(MF->getAlignment(), F);
505 if (MAI->hasDotTypeDotSizeDirective())
506 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
509 F->printAsOperand(OutStreamer.GetCommentOS(),
510 /*PrintType=*/false, F->getParent());
511 OutStreamer.GetCommentOS() << '\n';
514 // Emit the CurrentFnSym. This is a virtual function to allow targets to
515 // do their wild and crazy things as required.
516 EmitFunctionEntryLabel();
518 // If the function had address-taken blocks that got deleted, then we have
519 // references to the dangling symbols. Emit them at the start of the function
520 // so that we don't get references to undefined symbols.
521 std::vector<MCSymbol*> DeadBlockSyms;
522 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
523 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
524 OutStreamer.AddComment("Address taken block that was later removed");
525 OutStreamer.EmitLabel(DeadBlockSyms[i]);
528 // Emit pre-function debug and/or EH information.
529 for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
530 const HandlerInfo &OI = Handlers[I];
531 NamedRegionTimer T(OI.TimerName, OI.TimerGroupName, TimePassesIsEnabled);
532 OI.Handler->beginFunction(MF);
535 // Emit the prefix data.
536 if (F->hasPrefixData())
537 EmitGlobalConstant(F->getPrefixData());
540 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
541 /// function. This can be overridden by targets as required to do custom stuff.
542 void AsmPrinter::EmitFunctionEntryLabel() {
543 // The function label could have already been emitted if two symbols end up
544 // conflicting due to asm renaming. Detect this and emit an error.
545 if (CurrentFnSym->isUndefined())
546 return OutStreamer.EmitLabel(CurrentFnSym);
548 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
549 "' label emitted multiple times to assembly file");
552 /// emitComments - Pretty-print comments for instructions.
553 static void emitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
554 const MachineFunction *MF = MI.getParent()->getParent();
555 const TargetMachine &TM = MF->getTarget();
557 // Check for spills and reloads
560 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
562 // We assume a single instruction only has a spill or reload, not
564 const MachineMemOperand *MMO;
565 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
566 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
567 MMO = *MI.memoperands_begin();
568 CommentOS << MMO->getSize() << "-byte Reload\n";
570 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
571 if (FrameInfo->isSpillSlotObjectIndex(FI))
572 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
573 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
574 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
575 MMO = *MI.memoperands_begin();
576 CommentOS << MMO->getSize() << "-byte Spill\n";
578 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
579 if (FrameInfo->isSpillSlotObjectIndex(FI))
580 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
583 // Check for spill-induced copies
584 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
585 CommentOS << " Reload Reuse\n";
588 /// emitImplicitDef - This method emits the specified machine instruction
589 /// that is an implicit def.
590 void AsmPrinter::emitImplicitDef(const MachineInstr *MI) const {
591 unsigned RegNo = MI->getOperand(0).getReg();
592 OutStreamer.AddComment(Twine("implicit-def: ") +
593 TM.getRegisterInfo()->getName(RegNo));
594 OutStreamer.AddBlankLine();
597 static void emitKill(const MachineInstr *MI, AsmPrinter &AP) {
598 std::string Str = "kill:";
599 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
600 const MachineOperand &Op = MI->getOperand(i);
601 assert(Op.isReg() && "KILL instruction must have only register operands");
603 Str += AP.TM.getRegisterInfo()->getName(Op.getReg());
604 Str += (Op.isDef() ? "<def>" : "<kill>");
606 AP.OutStreamer.AddComment(Str);
607 AP.OutStreamer.AddBlankLine();
610 /// emitDebugValueComment - This method handles the target-independent form
611 /// of DBG_VALUE, returning true if it was able to do so. A false return
612 /// means the target will need to handle MI in EmitInstruction.
613 static bool emitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
614 // This code handles only the 3-operand target-independent form.
615 if (MI->getNumOperands() != 3)
618 SmallString<128> Str;
619 raw_svector_ostream OS(Str);
620 OS << "DEBUG_VALUE: ";
622 DIVariable V(MI->getOperand(2).getMetadata());
623 if (V.getContext().isSubprogram()) {
624 StringRef Name = DISubprogram(V.getContext()).getDisplayName();
628 OS << V.getName() << " <- ";
630 // The second operand is only an offset if it's an immediate.
631 bool Deref = MI->getOperand(0).isReg() && MI->getOperand(1).isImm();
632 int64_t Offset = Deref ? MI->getOperand(1).getImm() : 0;
634 // Register or immediate value. Register 0 means undef.
635 if (MI->getOperand(0).isFPImm()) {
636 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
637 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
638 OS << (double)APF.convertToFloat();
639 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
640 OS << APF.convertToDouble();
642 // There is no good way to print long double. Convert a copy to
643 // double. Ah well, it's only a comment.
645 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
647 OS << "(long double) " << APF.convertToDouble();
649 } else if (MI->getOperand(0).isImm()) {
650 OS << MI->getOperand(0).getImm();
651 } else if (MI->getOperand(0).isCImm()) {
652 MI->getOperand(0).getCImm()->getValue().print(OS, false /*isSigned*/);
655 if (MI->getOperand(0).isReg()) {
656 Reg = MI->getOperand(0).getReg();
658 assert(MI->getOperand(0).isFI() && "Unknown operand type");
659 const TargetFrameLowering *TFI = AP.TM.getFrameLowering();
660 Offset += TFI->getFrameIndexReference(*AP.MF,
661 MI->getOperand(0).getIndex(), Reg);
665 // Suppress offset, it is not meaningful here.
667 // NOTE: Want this comment at start of line, don't emit with AddComment.
668 AP.OutStreamer.emitRawComment(OS.str());
673 OS << AP.TM.getRegisterInfo()->getName(Reg);
677 OS << '+' << Offset << ']';
679 // NOTE: Want this comment at start of line, don't emit with AddComment.
680 AP.OutStreamer.emitRawComment(OS.str());
684 AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() {
685 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI &&
686 MF->getFunction()->needsUnwindTableEntry())
689 if (MMI->hasDebugInfo())
695 bool AsmPrinter::needsSEHMoves() {
696 return MAI->getExceptionHandlingType() == ExceptionHandling::Win64 &&
697 MF->getFunction()->needsUnwindTableEntry();
700 void AsmPrinter::emitCFIInstruction(const MachineInstr &MI) {
701 ExceptionHandling::ExceptionsType ExceptionHandlingType =
702 MAI->getExceptionHandlingType();
703 if (ExceptionHandlingType != ExceptionHandling::DwarfCFI &&
704 ExceptionHandlingType != ExceptionHandling::ARM)
707 if (needsCFIMoves() == CFI_M_None)
710 if (MMI->getCompactUnwindEncoding() != 0)
711 OutStreamer.EmitCompactUnwindEncoding(MMI->getCompactUnwindEncoding());
713 const MachineModuleInfo &MMI = MF->getMMI();
714 const std::vector<MCCFIInstruction> &Instrs = MMI.getFrameInstructions();
715 unsigned CFIIndex = MI.getOperand(0).getCFIIndex();
716 const MCCFIInstruction &CFI = Instrs[CFIIndex];
717 emitCFIInstruction(CFI);
720 /// EmitFunctionBody - This method emits the body and trailer for a
722 void AsmPrinter::EmitFunctionBody() {
723 // Emit target-specific gunk before the function body.
724 EmitFunctionBodyStart();
726 bool ShouldPrintDebugScopes = MMI->hasDebugInfo();
728 // Print out code for the function.
729 bool HasAnyRealCode = false;
730 const MachineInstr *LastMI = 0;
731 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
733 // Print a label for the basic block.
734 EmitBasicBlockStart(I);
735 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
739 // Print the assembly for the instruction.
740 if (!II->isPosition() && !II->isImplicitDef() && !II->isKill() &&
741 !II->isDebugValue()) {
742 HasAnyRealCode = true;
746 if (ShouldPrintDebugScopes) {
747 for (unsigned III = 0, EEE = Handlers.size(); III != EEE; ++III) {
748 const HandlerInfo &OI = Handlers[III];
749 NamedRegionTimer T(OI.TimerName, OI.TimerGroupName,
750 TimePassesIsEnabled);
751 OI.Handler->beginInstruction(II);
756 emitComments(*II, OutStreamer.GetCommentOS());
758 switch (II->getOpcode()) {
759 case TargetOpcode::CFI_INSTRUCTION:
760 emitCFIInstruction(*II);
763 case TargetOpcode::EH_LABEL:
764 case TargetOpcode::GC_LABEL:
765 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol());
767 case TargetOpcode::INLINEASM:
770 case TargetOpcode::DBG_VALUE:
772 if (!emitDebugValueComment(II, *this))
776 case TargetOpcode::IMPLICIT_DEF:
777 if (isVerbose()) emitImplicitDef(II);
779 case TargetOpcode::KILL:
780 if (isVerbose()) emitKill(II, *this);
787 if (ShouldPrintDebugScopes) {
788 for (unsigned III = 0, EEE = Handlers.size(); III != EEE; ++III) {
789 const HandlerInfo &OI = Handlers[III];
790 NamedRegionTimer T(OI.TimerName, OI.TimerGroupName,
791 TimePassesIsEnabled);
792 OI.Handler->endInstruction();
798 // If the last instruction was a prolog label, then we have a situation where
799 // we emitted a prolog but no function body. This results in the ending prolog
800 // label equaling the end of function label and an invalid "row" in the
801 // FDE. We need to emit a noop in this situation so that the FDE's rows are
803 bool RequiresNoop = LastMI && LastMI->isCFIInstruction();
805 // If the function is empty and the object file uses .subsections_via_symbols,
806 // then we need to emit *something* to the function body to prevent the
807 // labels from collapsing together. Just emit a noop.
808 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) || RequiresNoop) {
810 TM.getInstrInfo()->getNoopForMachoTarget(Noop);
811 if (Noop.getOpcode()) {
812 OutStreamer.AddComment("avoids zero-length function");
813 OutStreamer.EmitInstruction(Noop, getSubtargetInfo());
814 } else // Target not mc-ized yet.
815 OutStreamer.EmitRawText(StringRef("\tnop\n"));
818 const Function *F = MF->getFunction();
819 for (Function::const_iterator i = F->begin(), e = F->end(); i != e; ++i) {
820 const BasicBlock *BB = i;
821 if (!BB->hasAddressTaken())
823 MCSymbol *Sym = GetBlockAddressSymbol(BB);
824 if (Sym->isDefined())
826 OutStreamer.AddComment("Address of block that was removed by CodeGen");
827 OutStreamer.EmitLabel(Sym);
830 // Emit target-specific gunk after the function body.
831 EmitFunctionBodyEnd();
833 // If the target wants a .size directive for the size of the function, emit
835 if (MAI->hasDotTypeDotSizeDirective()) {
836 // Create a symbol for the end of function, so we can get the size as
837 // difference between the function label and the temp label.
838 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
839 OutStreamer.EmitLabel(FnEndLabel);
841 const MCExpr *SizeExp =
842 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
843 MCSymbolRefExpr::Create(CurrentFnSymForSize,
846 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
849 // Emit post-function debug and/or EH information.
850 for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
851 const HandlerInfo &OI = Handlers[I];
852 NamedRegionTimer T(OI.TimerName, OI.TimerGroupName, TimePassesIsEnabled);
853 OI.Handler->endFunction(MF);
857 // Print out jump tables referenced by the function.
860 OutStreamer.AddBlankLine();
863 bool AsmPrinter::doFinalization(Module &M) {
864 // Emit global variables.
865 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
867 EmitGlobalVariable(I);
869 // Emit visibility info for declarations
870 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
871 const Function &F = *I;
872 if (!F.isDeclaration())
874 GlobalValue::VisibilityTypes V = F.getVisibility();
875 if (V == GlobalValue::DefaultVisibility)
878 MCSymbol *Name = getSymbol(&F);
879 EmitVisibility(Name, V, false);
882 // Emit module flags.
883 SmallVector<Module::ModuleFlagEntry, 8> ModuleFlags;
884 M.getModuleFlagsMetadata(ModuleFlags);
885 if (!ModuleFlags.empty())
886 getObjFileLowering().emitModuleFlags(OutStreamer, ModuleFlags, *Mang, TM);
888 // Make sure we wrote out everything we need.
891 // Finalize debug and EH information.
892 for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
893 const HandlerInfo &OI = Handlers[I];
894 NamedRegionTimer T(OI.TimerName, OI.TimerGroupName,
895 TimePassesIsEnabled);
896 OI.Handler->endModule();
902 // If the target wants to know about weak references, print them all.
903 if (MAI->getWeakRefDirective()) {
904 // FIXME: This is not lazy, it would be nice to only print weak references
905 // to stuff that is actually used. Note that doing so would require targets
906 // to notice uses in operands (due to constant exprs etc). This should
907 // happen with the MC stuff eventually.
909 // Print out module-level global variables here.
910 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
912 if (!I->hasExternalWeakLinkage()) continue;
913 OutStreamer.EmitSymbolAttribute(getSymbol(I), MCSA_WeakReference);
916 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
917 if (!I->hasExternalWeakLinkage()) continue;
918 OutStreamer.EmitSymbolAttribute(getSymbol(I), MCSA_WeakReference);
922 if (MAI->hasSetDirective()) {
923 OutStreamer.AddBlankLine();
924 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
926 MCSymbol *Name = getSymbol(I);
928 const GlobalValue *GV = I->getAliasedGlobal();
929 assert(!GV->isDeclaration());
930 MCSymbol *Target = getSymbol(GV);
932 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
933 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
934 else if (I->hasWeakLinkage() || I->hasLinkOnceLinkage())
935 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
937 assert(I->hasLocalLinkage() && "Invalid alias linkage");
939 EmitVisibility(Name, I->getVisibility());
941 // Emit the directives as assignments aka .set:
942 OutStreamer.EmitAssignment(Name,
943 MCSymbolRefExpr::Create(Target, OutContext));
947 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
948 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
949 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
950 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
951 MP->finishAssembly(*this);
953 // Emit llvm.ident metadata in an '.ident' directive.
956 // If we don't have any trampolines, then we don't require stack memory
957 // to be executable. Some targets have a directive to declare this.
958 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
959 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
960 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext))
961 OutStreamer.SwitchSection(S);
963 // Allow the target to emit any magic that it wants at the end of the file,
964 // after everything else has gone out.
967 delete Mang; Mang = 0;
970 OutStreamer.Finish();
976 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
978 // Get the function symbol.
979 CurrentFnSym = getSymbol(MF.getFunction());
980 CurrentFnSymForSize = CurrentFnSym;
983 LI = &getAnalysis<MachineLoopInfo>();
987 // SectionCPs - Keep track the alignment, constpool entries per Section.
991 SmallVector<unsigned, 4> CPEs;
992 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
996 /// EmitConstantPool - Print to the current output stream assembly
997 /// representations of the constants in the constant pool MCP. This is
998 /// used to print out constants which have been "spilled to memory" by
999 /// the code generator.
1001 void AsmPrinter::EmitConstantPool() {
1002 const MachineConstantPool *MCP = MF->getConstantPool();
1003 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
1004 if (CP.empty()) return;
1006 // Calculate sections for constant pool entries. We collect entries to go into
1007 // the same section together to reduce amount of section switch statements.
1008 SmallVector<SectionCPs, 4> CPSections;
1009 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
1010 const MachineConstantPoolEntry &CPE = CP[i];
1011 unsigned Align = CPE.getAlignment();
1014 switch (CPE.getRelocationInfo()) {
1015 default: llvm_unreachable("Unknown section kind");
1016 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
1018 Kind = SectionKind::getReadOnlyWithRelLocal();
1021 switch (TM.getDataLayout()->getTypeAllocSize(CPE.getType())) {
1022 case 4: Kind = SectionKind::getMergeableConst4(); break;
1023 case 8: Kind = SectionKind::getMergeableConst8(); break;
1024 case 16: Kind = SectionKind::getMergeableConst16();break;
1025 default: Kind = SectionKind::getMergeableConst(); break;
1029 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
1031 // The number of sections are small, just do a linear search from the
1032 // last section to the first.
1034 unsigned SecIdx = CPSections.size();
1035 while (SecIdx != 0) {
1036 if (CPSections[--SecIdx].S == S) {
1042 SecIdx = CPSections.size();
1043 CPSections.push_back(SectionCPs(S, Align));
1046 if (Align > CPSections[SecIdx].Alignment)
1047 CPSections[SecIdx].Alignment = Align;
1048 CPSections[SecIdx].CPEs.push_back(i);
1051 // Now print stuff into the calculated sections.
1052 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
1053 OutStreamer.SwitchSection(CPSections[i].S);
1054 EmitAlignment(Log2_32(CPSections[i].Alignment));
1056 unsigned Offset = 0;
1057 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
1058 unsigned CPI = CPSections[i].CPEs[j];
1059 MachineConstantPoolEntry CPE = CP[CPI];
1061 // Emit inter-object padding for alignment.
1062 unsigned AlignMask = CPE.getAlignment() - 1;
1063 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
1064 OutStreamer.EmitZeros(NewOffset - Offset);
1066 Type *Ty = CPE.getType();
1067 Offset = NewOffset + TM.getDataLayout()->getTypeAllocSize(Ty);
1068 OutStreamer.EmitLabel(GetCPISymbol(CPI));
1070 if (CPE.isMachineConstantPoolEntry())
1071 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
1073 EmitGlobalConstant(CPE.Val.ConstVal);
1078 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
1079 /// by the current function to the current output stream.
1081 void AsmPrinter::EmitJumpTableInfo() {
1082 const DataLayout *DL = MF->getTarget().getDataLayout();
1083 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1084 if (MJTI == 0) return;
1085 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
1086 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1087 if (JT.empty()) return;
1089 // Pick the directive to use to print the jump table entries, and switch to
1090 // the appropriate section.
1091 const Function *F = MF->getFunction();
1092 bool JTInDiffSection = false;
1093 if (// In PIC mode, we need to emit the jump table to the same section as the
1094 // function body itself, otherwise the label differences won't make sense.
1095 // FIXME: Need a better predicate for this: what about custom entries?
1096 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
1097 // We should also do if the section name is NULL or function is declared
1098 // in discardable section
1099 // FIXME: this isn't the right predicate, should be based on the MCSection
1100 // for the function.
1101 F->isWeakForLinker()) {
1102 OutStreamer.SwitchSection(
1103 getObjFileLowering().SectionForGlobal(F, *Mang, TM));
1105 // Otherwise, drop it in the readonly section.
1106 const MCSection *ReadOnlySection =
1107 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
1108 OutStreamer.SwitchSection(ReadOnlySection);
1109 JTInDiffSection = true;
1112 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getDataLayout())));
1114 // Jump tables in code sections are marked with a data_region directive
1115 // where that's supported.
1116 if (!JTInDiffSection)
1117 OutStreamer.EmitDataRegion(MCDR_DataRegionJT32);
1119 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
1120 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1122 // If this jump table was deleted, ignore it.
1123 if (JTBBs.empty()) continue;
1125 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
1126 // .set directive for each unique entry. This reduces the number of
1127 // relocations the assembler will generate for the jump table.
1128 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
1129 MAI->hasSetDirective()) {
1130 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
1131 const TargetLowering *TLI = TM.getTargetLowering();
1132 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
1133 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
1134 const MachineBasicBlock *MBB = JTBBs[ii];
1135 if (!EmittedSets.insert(MBB)) continue;
1137 // .set LJTSet, LBB32-base
1139 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1140 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
1141 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
1145 // On some targets (e.g. Darwin) we want to emit two consecutive labels
1146 // before each jump table. The first label is never referenced, but tells
1147 // the assembler and linker the extents of the jump table object. The
1148 // second label is actually referenced by the code.
1149 if (JTInDiffSection && DL->hasLinkerPrivateGlobalPrefix())
1150 // FIXME: This doesn't have to have any specific name, just any randomly
1151 // named and numbered 'l' label would work. Simplify GetJTISymbol.
1152 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
1154 OutStreamer.EmitLabel(GetJTISymbol(JTI));
1156 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
1157 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
1159 if (!JTInDiffSection)
1160 OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
1163 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
1165 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
1166 const MachineBasicBlock *MBB,
1167 unsigned UID) const {
1168 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block");
1169 const MCExpr *Value = 0;
1170 switch (MJTI->getEntryKind()) {
1171 case MachineJumpTableInfo::EK_Inline:
1172 llvm_unreachable("Cannot emit EK_Inline jump table entry");
1173 case MachineJumpTableInfo::EK_Custom32:
1174 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
1177 case MachineJumpTableInfo::EK_BlockAddress:
1178 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
1180 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1182 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
1183 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
1184 // with a relocation as gp-relative, e.g.:
1186 MCSymbol *MBBSym = MBB->getSymbol();
1187 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1191 case MachineJumpTableInfo::EK_GPRel64BlockAddress: {
1192 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded
1193 // with a relocation as gp-relative, e.g.:
1195 MCSymbol *MBBSym = MBB->getSymbol();
1196 OutStreamer.EmitGPRel64Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1200 case MachineJumpTableInfo::EK_LabelDifference32: {
1201 // EK_LabelDifference32 - Each entry is the address of the block minus
1202 // the address of the jump table. This is used for PIC jump tables where
1203 // gprel32 is not supported. e.g.:
1204 // .word LBB123 - LJTI1_2
1205 // If the .set directive is supported, this is emitted as:
1206 // .set L4_5_set_123, LBB123 - LJTI1_2
1207 // .word L4_5_set_123
1209 // If we have emitted set directives for the jump table entries, print
1210 // them rather than the entries themselves. If we're emitting PIC, then
1211 // emit the table entries as differences between two text section labels.
1212 if (MAI->hasSetDirective()) {
1213 // If we used .set, reference the .set's symbol.
1214 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
1218 // Otherwise, use the difference as the jump table entry.
1219 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1220 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
1221 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
1226 assert(Value && "Unknown entry kind!");
1228 unsigned EntrySize = MJTI->getEntrySize(*TM.getDataLayout());
1229 OutStreamer.EmitValue(Value, EntrySize);
1233 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
1234 /// special global used by LLVM. If so, emit it and return true, otherwise
1235 /// do nothing and return false.
1236 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
1237 if (GV->getName() == "llvm.used") {
1238 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
1239 EmitLLVMUsedList(cast<ConstantArray>(GV->getInitializer()));
1243 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
1244 if (GV->getSection() == "llvm.metadata" ||
1245 GV->hasAvailableExternallyLinkage())
1248 if (!GV->hasAppendingLinkage()) return false;
1250 assert(GV->hasInitializer() && "Not a special LLVM global!");
1252 if (GV->getName() == "llvm.global_ctors") {
1253 EmitXXStructorList(GV->getInitializer(), /* isCtor */ true);
1255 if (TM.getRelocationModel() == Reloc::Static &&
1256 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1257 StringRef Sym(".constructors_used");
1258 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1264 if (GV->getName() == "llvm.global_dtors") {
1265 EmitXXStructorList(GV->getInitializer(), /* isCtor */ false);
1267 if (TM.getRelocationModel() == Reloc::Static &&
1268 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1269 StringRef Sym(".destructors_used");
1270 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1279 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1280 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1281 /// is true, as being used with this directive.
1282 void AsmPrinter::EmitLLVMUsedList(const ConstantArray *InitList) {
1283 // Should be an array of 'i8*'.
1284 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1285 const GlobalValue *GV =
1286 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1288 OutStreamer.EmitSymbolAttribute(getSymbol(GV), MCSA_NoDeadStrip);
1292 /// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
1294 void AsmPrinter::EmitXXStructorList(const Constant *List, bool isCtor) {
1295 // Should be an array of '{ int, void ()* }' structs. The first value is the
1297 if (!isa<ConstantArray>(List)) return;
1299 // Sanity check the structors list.
1300 const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1301 if (!InitList) return; // Not an array!
1302 StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType());
1303 if (!ETy || ETy->getNumElements() != 2) return; // Not an array of pairs!
1304 if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) ||
1305 !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr).
1307 // Gather the structors in a form that's convenient for sorting by priority.
1308 typedef std::pair<unsigned, Constant *> Structor;
1309 SmallVector<Structor, 8> Structors;
1310 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1311 ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i));
1312 if (!CS) continue; // Malformed.
1313 if (CS->getOperand(1)->isNullValue())
1314 break; // Found a null terminator, skip the rest.
1315 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
1316 if (!Priority) continue; // Malformed.
1317 Structors.push_back(std::make_pair(Priority->getLimitedValue(65535),
1318 CS->getOperand(1)));
1321 // Emit the function pointers in the target-specific order
1322 const DataLayout *DL = TM.getDataLayout();
1323 unsigned Align = Log2_32(DL->getPointerPrefAlignment());
1324 std::stable_sort(Structors.begin(), Structors.end(), less_first());
1325 for (unsigned i = 0, e = Structors.size(); i != e; ++i) {
1326 const MCSection *OutputSection =
1328 getObjFileLowering().getStaticCtorSection(Structors[i].first) :
1329 getObjFileLowering().getStaticDtorSection(Structors[i].first));
1330 OutStreamer.SwitchSection(OutputSection);
1331 if (OutStreamer.getCurrentSection() != OutStreamer.getPreviousSection())
1332 EmitAlignment(Align);
1333 EmitXXStructor(Structors[i].second);
1337 void AsmPrinter::EmitModuleIdents(Module &M) {
1338 if (!MAI->hasIdentDirective())
1341 if (const NamedMDNode *NMD = M.getNamedMetadata("llvm.ident")) {
1342 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
1343 const MDNode *N = NMD->getOperand(i);
1344 assert(N->getNumOperands() == 1 &&
1345 "llvm.ident metadata entry can have only one operand");
1346 const MDString *S = cast<MDString>(N->getOperand(0));
1347 OutStreamer.EmitIdent(S->getString());
1352 //===--------------------------------------------------------------------===//
1353 // Emission and print routines
1356 /// EmitInt8 - Emit a byte directive and value.
1358 void AsmPrinter::EmitInt8(int Value) const {
1359 OutStreamer.EmitIntValue(Value, 1);
1362 /// EmitInt16 - Emit a short directive and value.
1364 void AsmPrinter::EmitInt16(int Value) const {
1365 OutStreamer.EmitIntValue(Value, 2);
1368 /// EmitInt32 - Emit a long directive and value.
1370 void AsmPrinter::EmitInt32(int Value) const {
1371 OutStreamer.EmitIntValue(Value, 4);
1374 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
1375 /// in bytes of the directive is specified by Size and Hi/Lo specify the
1376 /// labels. This implicitly uses .set if it is available.
1377 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1378 unsigned Size) const {
1379 // Get the Hi-Lo expression.
1380 const MCExpr *Diff =
1381 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1382 MCSymbolRefExpr::Create(Lo, OutContext),
1385 if (!MAI->hasSetDirective()) {
1386 OutStreamer.EmitValue(Diff, Size);
1390 // Otherwise, emit with .set (aka assignment).
1391 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1392 OutStreamer.EmitAssignment(SetLabel, Diff);
1393 OutStreamer.EmitSymbolValue(SetLabel, Size);
1396 /// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo"
1397 /// where the size in bytes of the directive is specified by Size and Hi/Lo
1398 /// specify the labels. This implicitly uses .set if it is available.
1399 void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset,
1401 unsigned Size) const {
1403 // Emit Hi+Offset - Lo
1404 // Get the Hi+Offset expression.
1405 const MCExpr *Plus =
1406 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext),
1407 MCConstantExpr::Create(Offset, OutContext),
1410 // Get the Hi+Offset-Lo expression.
1411 const MCExpr *Diff =
1412 MCBinaryExpr::CreateSub(Plus,
1413 MCSymbolRefExpr::Create(Lo, OutContext),
1416 if (!MAI->hasSetDirective())
1417 OutStreamer.EmitValue(Diff, Size);
1419 // Otherwise, emit with .set (aka assignment).
1420 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1421 OutStreamer.EmitAssignment(SetLabel, Diff);
1422 OutStreamer.EmitSymbolValue(SetLabel, Size);
1426 /// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
1427 /// where the size in bytes of the directive is specified by Size and Label
1428 /// specifies the label. This implicitly uses .set if it is available.
1429 void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset,
1431 bool IsSectionRelative) const {
1432 if (MAI->needsDwarfSectionOffsetDirective() && IsSectionRelative) {
1433 OutStreamer.EmitCOFFSecRel32(Label);
1437 // Emit Label+Offset (or just Label if Offset is zero)
1438 const MCExpr *Expr = MCSymbolRefExpr::Create(Label, OutContext);
1440 Expr = MCBinaryExpr::CreateAdd(
1441 Expr, MCConstantExpr::Create(Offset, OutContext), OutContext);
1443 OutStreamer.EmitValue(Expr, Size);
1446 //===----------------------------------------------------------------------===//
1448 // EmitAlignment - Emit an alignment directive to the specified power of
1449 // two boundary. For example, if you pass in 3 here, you will get an 8
1450 // byte alignment. If a global value is specified, and if that global has
1451 // an explicit alignment requested, it will override the alignment request
1452 // if required for correctness.
1454 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV) const {
1455 if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getDataLayout(), NumBits);
1457 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.
1459 if (getCurrentSection()->getKind().isText())
1460 OutStreamer.EmitCodeAlignment(1 << NumBits);
1462 OutStreamer.EmitValueToAlignment(1 << NumBits);
1465 //===----------------------------------------------------------------------===//
1466 // Constant emission.
1467 //===----------------------------------------------------------------------===//
1469 /// lowerConstant - Lower the specified LLVM Constant to an MCExpr.
1471 static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP) {
1472 MCContext &Ctx = AP.OutContext;
1474 if (CV->isNullValue() || isa<UndefValue>(CV))
1475 return MCConstantExpr::Create(0, Ctx);
1477 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1478 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1480 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1481 return MCSymbolRefExpr::Create(AP.getSymbol(GV), Ctx);
1483 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1484 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1486 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1488 llvm_unreachable("Unknown constant value to lower!");
1491 if (const MCExpr *RelocExpr =
1492 AP.getObjFileLowering().getExecutableRelativeSymbol(CE, *AP.Mang,
1496 switch (CE->getOpcode()) {
1498 // If the code isn't optimized, there may be outstanding folding
1499 // opportunities. Attempt to fold the expression using DataLayout as a
1500 // last resort before giving up.
1502 ConstantFoldConstantExpression(CE, AP.TM.getDataLayout()))
1504 return lowerConstant(C, AP);
1506 // Otherwise report the problem to the user.
1509 raw_string_ostream OS(S);
1510 OS << "Unsupported expression in static initializer: ";
1511 CE->printAsOperand(OS, /*PrintType=*/false,
1512 !AP.MF ? 0 : AP.MF->getFunction()->getParent());
1513 report_fatal_error(OS.str());
1515 case Instruction::GetElementPtr: {
1516 const DataLayout &DL = *AP.TM.getDataLayout();
1517 // Generate a symbolic expression for the byte address
1518 APInt OffsetAI(DL.getPointerTypeSizeInBits(CE->getType()), 0);
1519 cast<GEPOperator>(CE)->accumulateConstantOffset(DL, OffsetAI);
1521 const MCExpr *Base = lowerConstant(CE->getOperand(0), AP);
1525 int64_t Offset = OffsetAI.getSExtValue();
1526 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1530 case Instruction::Trunc:
1531 // We emit the value and depend on the assembler to truncate the generated
1532 // expression properly. This is important for differences between
1533 // blockaddress labels. Since the two labels are in the same function, it
1534 // is reasonable to treat their delta as a 32-bit value.
1536 case Instruction::BitCast:
1537 return lowerConstant(CE->getOperand(0), AP);
1539 case Instruction::IntToPtr: {
1540 const DataLayout &DL = *AP.TM.getDataLayout();
1541 // Handle casts to pointers by changing them into casts to the appropriate
1542 // integer type. This promotes constant folding and simplifies this code.
1543 Constant *Op = CE->getOperand(0);
1544 Op = ConstantExpr::getIntegerCast(Op, DL.getIntPtrType(CV->getType()),
1546 return lowerConstant(Op, AP);
1549 case Instruction::PtrToInt: {
1550 const DataLayout &DL = *AP.TM.getDataLayout();
1551 // Support only foldable casts to/from pointers that can be eliminated by
1552 // changing the pointer to the appropriately sized integer type.
1553 Constant *Op = CE->getOperand(0);
1554 Type *Ty = CE->getType();
1556 const MCExpr *OpExpr = lowerConstant(Op, AP);
1558 // We can emit the pointer value into this slot if the slot is an
1559 // integer slot equal to the size of the pointer.
1560 if (DL.getTypeAllocSize(Ty) == DL.getTypeAllocSize(Op->getType()))
1563 // Otherwise the pointer is smaller than the resultant integer, mask off
1564 // the high bits so we are sure to get a proper truncation if the input is
1566 unsigned InBits = DL.getTypeAllocSizeInBits(Op->getType());
1567 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1568 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1571 // The MC library also has a right-shift operator, but it isn't consistently
1572 // signed or unsigned between different targets.
1573 case Instruction::Add:
1574 case Instruction::Sub:
1575 case Instruction::Mul:
1576 case Instruction::SDiv:
1577 case Instruction::SRem:
1578 case Instruction::Shl:
1579 case Instruction::And:
1580 case Instruction::Or:
1581 case Instruction::Xor: {
1582 const MCExpr *LHS = lowerConstant(CE->getOperand(0), AP);
1583 const MCExpr *RHS = lowerConstant(CE->getOperand(1), AP);
1584 switch (CE->getOpcode()) {
1585 default: llvm_unreachable("Unknown binary operator constant cast expr");
1586 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1587 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1588 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1589 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1590 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1591 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1592 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1593 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1594 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1600 static void emitGlobalConstantImpl(const Constant *C, AsmPrinter &AP);
1602 /// isRepeatedByteSequence - Determine whether the given value is
1603 /// composed of a repeated sequence of identical bytes and return the
1604 /// byte value. If it is not a repeated sequence, return -1.
1605 static int isRepeatedByteSequence(const ConstantDataSequential *V) {
1606 StringRef Data = V->getRawDataValues();
1607 assert(!Data.empty() && "Empty aggregates should be CAZ node");
1609 for (unsigned i = 1, e = Data.size(); i != e; ++i)
1610 if (Data[i] != C) return -1;
1611 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1.
1615 /// isRepeatedByteSequence - Determine whether the given value is
1616 /// composed of a repeated sequence of identical bytes and return the
1617 /// byte value. If it is not a repeated sequence, return -1.
1618 static int isRepeatedByteSequence(const Value *V, TargetMachine &TM) {
1620 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
1621 if (CI->getBitWidth() > 64) return -1;
1623 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(V->getType());
1624 uint64_t Value = CI->getZExtValue();
1626 // Make sure the constant is at least 8 bits long and has a power
1627 // of 2 bit width. This guarantees the constant bit width is
1628 // always a multiple of 8 bits, avoiding issues with padding out
1629 // to Size and other such corner cases.
1630 if (CI->getBitWidth() < 8 || !isPowerOf2_64(CI->getBitWidth())) return -1;
1632 uint8_t Byte = static_cast<uint8_t>(Value);
1634 for (unsigned i = 1; i < Size; ++i) {
1636 if (static_cast<uint8_t>(Value) != Byte) return -1;
1640 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) {
1641 // Make sure all array elements are sequences of the same repeated
1643 assert(CA->getNumOperands() != 0 && "Should be a CAZ");
1644 int Byte = isRepeatedByteSequence(CA->getOperand(0), TM);
1645 if (Byte == -1) return -1;
1647 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i) {
1648 int ThisByte = isRepeatedByteSequence(CA->getOperand(i), TM);
1649 if (ThisByte == -1) return -1;
1650 if (Byte != ThisByte) return -1;
1655 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V))
1656 return isRepeatedByteSequence(CDS);
1661 static void emitGlobalConstantDataSequential(const ConstantDataSequential *CDS,
1664 // See if we can aggregate this into a .fill, if so, emit it as such.
1665 int Value = isRepeatedByteSequence(CDS, AP.TM);
1667 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CDS->getType());
1668 // Don't emit a 1-byte object as a .fill.
1670 return AP.OutStreamer.EmitFill(Bytes, Value);
1673 // If this can be emitted with .ascii/.asciz, emit it as such.
1674 if (CDS->isString())
1675 return AP.OutStreamer.EmitBytes(CDS->getAsString());
1677 // Otherwise, emit the values in successive locations.
1678 unsigned ElementByteSize = CDS->getElementByteSize();
1679 if (isa<IntegerType>(CDS->getElementType())) {
1680 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1682 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1683 CDS->getElementAsInteger(i));
1684 AP.OutStreamer.EmitIntValue(CDS->getElementAsInteger(i),
1687 } else if (ElementByteSize == 4) {
1688 // FP Constants are printed as integer constants to avoid losing
1690 assert(CDS->getElementType()->isFloatTy());
1691 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1697 F = CDS->getElementAsFloat(i);
1699 AP.OutStreamer.GetCommentOS() << "float " << F << '\n';
1700 AP.OutStreamer.EmitIntValue(I, 4);
1703 assert(CDS->getElementType()->isDoubleTy());
1704 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1710 F = CDS->getElementAsDouble(i);
1712 AP.OutStreamer.GetCommentOS() << "double " << F << '\n';
1713 AP.OutStreamer.EmitIntValue(I, 8);
1717 const DataLayout &DL = *AP.TM.getDataLayout();
1718 unsigned Size = DL.getTypeAllocSize(CDS->getType());
1719 unsigned EmittedSize = DL.getTypeAllocSize(CDS->getType()->getElementType()) *
1720 CDS->getNumElements();
1721 if (unsigned Padding = Size - EmittedSize)
1722 AP.OutStreamer.EmitZeros(Padding);
1726 static void emitGlobalConstantArray(const ConstantArray *CA, AsmPrinter &AP) {
1727 // See if we can aggregate some values. Make sure it can be
1728 // represented as a series of bytes of the constant value.
1729 int Value = isRepeatedByteSequence(CA, AP.TM);
1732 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CA->getType());
1733 AP.OutStreamer.EmitFill(Bytes, Value);
1736 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1737 emitGlobalConstantImpl(CA->getOperand(i), AP);
1741 static void emitGlobalConstantVector(const ConstantVector *CV, AsmPrinter &AP) {
1742 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1743 emitGlobalConstantImpl(CV->getOperand(i), AP);
1745 const DataLayout &DL = *AP.TM.getDataLayout();
1746 unsigned Size = DL.getTypeAllocSize(CV->getType());
1747 unsigned EmittedSize = DL.getTypeAllocSize(CV->getType()->getElementType()) *
1748 CV->getType()->getNumElements();
1749 if (unsigned Padding = Size - EmittedSize)
1750 AP.OutStreamer.EmitZeros(Padding);
1753 static void emitGlobalConstantStruct(const ConstantStruct *CS, AsmPrinter &AP) {
1754 // Print the fields in successive locations. Pad to align if needed!
1755 const DataLayout *DL = AP.TM.getDataLayout();
1756 unsigned Size = DL->getTypeAllocSize(CS->getType());
1757 const StructLayout *Layout = DL->getStructLayout(CS->getType());
1758 uint64_t SizeSoFar = 0;
1759 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1760 const Constant *Field = CS->getOperand(i);
1762 // Check if padding is needed and insert one or more 0s.
1763 uint64_t FieldSize = DL->getTypeAllocSize(Field->getType());
1764 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1765 - Layout->getElementOffset(i)) - FieldSize;
1766 SizeSoFar += FieldSize + PadSize;
1768 // Now print the actual field value.
1769 emitGlobalConstantImpl(Field, AP);
1771 // Insert padding - this may include padding to increase the size of the
1772 // current field up to the ABI size (if the struct is not packed) as well
1773 // as padding to ensure that the next field starts at the right offset.
1774 AP.OutStreamer.EmitZeros(PadSize);
1776 assert(SizeSoFar == Layout->getSizeInBytes() &&
1777 "Layout of constant struct may be incorrect!");
1780 static void emitGlobalConstantFP(const ConstantFP *CFP, AsmPrinter &AP) {
1781 APInt API = CFP->getValueAPF().bitcastToAPInt();
1783 // First print a comment with what we think the original floating-point value
1784 // should have been.
1785 if (AP.isVerbose()) {
1786 SmallString<8> StrVal;
1787 CFP->getValueAPF().toString(StrVal);
1789 CFP->getType()->print(AP.OutStreamer.GetCommentOS());
1790 AP.OutStreamer.GetCommentOS() << ' ' << StrVal << '\n';
1793 // Now iterate through the APInt chunks, emitting them in endian-correct
1794 // order, possibly with a smaller chunk at beginning/end (e.g. for x87 80-bit
1796 unsigned NumBytes = API.getBitWidth() / 8;
1797 unsigned TrailingBytes = NumBytes % sizeof(uint64_t);
1798 const uint64_t *p = API.getRawData();
1800 // PPC's long double has odd notions of endianness compared to how LLVM
1801 // handles it: p[0] goes first for *big* endian on PPC.
1802 if (AP.TM.getDataLayout()->isBigEndian() != CFP->getType()->isPPC_FP128Ty()) {
1803 int Chunk = API.getNumWords() - 1;
1806 AP.OutStreamer.EmitIntValue(p[Chunk--], TrailingBytes);
1808 for (; Chunk >= 0; --Chunk)
1809 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1812 for (Chunk = 0; Chunk < NumBytes / sizeof(uint64_t); ++Chunk)
1813 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1816 AP.OutStreamer.EmitIntValue(p[Chunk], TrailingBytes);
1819 // Emit the tail padding for the long double.
1820 const DataLayout &DL = *AP.TM.getDataLayout();
1821 AP.OutStreamer.EmitZeros(DL.getTypeAllocSize(CFP->getType()) -
1822 DL.getTypeStoreSize(CFP->getType()));
1825 static void emitGlobalConstantLargeInt(const ConstantInt *CI, AsmPrinter &AP) {
1826 const DataLayout *DL = AP.TM.getDataLayout();
1827 unsigned BitWidth = CI->getBitWidth();
1829 // Copy the value as we may massage the layout for constants whose bit width
1830 // is not a multiple of 64-bits.
1831 APInt Realigned(CI->getValue());
1832 uint64_t ExtraBits = 0;
1833 unsigned ExtraBitsSize = BitWidth & 63;
1835 if (ExtraBitsSize) {
1836 // The bit width of the data is not a multiple of 64-bits.
1837 // The extra bits are expected to be at the end of the chunk of the memory.
1839 // * Nothing to be done, just record the extra bits to emit.
1841 // * Record the extra bits to emit.
1842 // * Realign the raw data to emit the chunks of 64-bits.
1843 if (DL->isBigEndian()) {
1844 // Basically the structure of the raw data is a chunk of 64-bits cells:
1845 // 0 1 BitWidth / 64
1846 // [chunk1][chunk2] ... [chunkN].
1847 // The most significant chunk is chunkN and it should be emitted first.
1848 // However, due to the alignment issue chunkN contains useless bits.
1849 // Realign the chunks so that they contain only useless information:
1850 // ExtraBits 0 1 (BitWidth / 64) - 1
1851 // chu[nk1 chu][nk2 chu] ... [nkN-1 chunkN]
1852 ExtraBits = Realigned.getRawData()[0] &
1853 (((uint64_t)-1) >> (64 - ExtraBitsSize));
1854 Realigned = Realigned.lshr(ExtraBitsSize);
1856 ExtraBits = Realigned.getRawData()[BitWidth / 64];
1859 // We don't expect assemblers to support integer data directives
1860 // for more than 64 bits, so we emit the data in at most 64-bit
1861 // quantities at a time.
1862 const uint64_t *RawData = Realigned.getRawData();
1863 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1864 uint64_t Val = DL->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1865 AP.OutStreamer.EmitIntValue(Val, 8);
1868 if (ExtraBitsSize) {
1869 // Emit the extra bits after the 64-bits chunks.
1871 // Emit a directive that fills the expected size.
1872 uint64_t Size = AP.TM.getDataLayout()->getTypeAllocSize(CI->getType());
1873 Size -= (BitWidth / 64) * 8;
1874 assert(Size && Size * 8 >= ExtraBitsSize &&
1875 (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize)))
1876 == ExtraBits && "Directive too small for extra bits.");
1877 AP.OutStreamer.EmitIntValue(ExtraBits, Size);
1881 static void emitGlobalConstantImpl(const Constant *CV, AsmPrinter &AP) {
1882 const DataLayout *DL = AP.TM.getDataLayout();
1883 uint64_t Size = DL->getTypeAllocSize(CV->getType());
1884 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV))
1885 return AP.OutStreamer.EmitZeros(Size);
1887 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1894 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1895 CI->getZExtValue());
1896 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size);
1899 emitGlobalConstantLargeInt(CI, AP);
1904 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1905 return emitGlobalConstantFP(CFP, AP);
1907 if (isa<ConstantPointerNull>(CV)) {
1908 AP.OutStreamer.EmitIntValue(0, Size);
1912 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV))
1913 return emitGlobalConstantDataSequential(CDS, AP);
1915 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1916 return emitGlobalConstantArray(CVA, AP);
1918 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1919 return emitGlobalConstantStruct(CVS, AP);
1921 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
1922 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
1924 if (CE->getOpcode() == Instruction::BitCast)
1925 return emitGlobalConstantImpl(CE->getOperand(0), AP);
1928 // If the constant expression's size is greater than 64-bits, then we have
1929 // to emit the value in chunks. Try to constant fold the value and emit it
1931 Constant *New = ConstantFoldConstantExpression(CE, DL);
1932 if (New && New != CE)
1933 return emitGlobalConstantImpl(New, AP);
1937 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1938 return emitGlobalConstantVector(V, AP);
1940 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1941 // thread the streamer with EmitValue.
1942 AP.OutStreamer.EmitValue(lowerConstant(CV, AP), Size);
1945 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1946 void AsmPrinter::EmitGlobalConstant(const Constant *CV) {
1947 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(CV->getType());
1949 emitGlobalConstantImpl(CV, *this);
1950 else if (MAI->hasSubsectionsViaSymbols()) {
1951 // If the global has zero size, emit a single byte so that two labels don't
1952 // look like they are at the same location.
1953 OutStreamer.EmitIntValue(0, 1);
1957 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1958 // Target doesn't support this yet!
1959 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1962 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1964 OS << '+' << Offset;
1965 else if (Offset < 0)
1969 //===----------------------------------------------------------------------===//
1970 // Symbol Lowering Routines.
1971 //===----------------------------------------------------------------------===//
1973 /// GetTempSymbol - Return the MCSymbol corresponding to the assembler
1974 /// temporary label with the specified stem and unique ID.
1975 MCSymbol *AsmPrinter::GetTempSymbol(Twine Name, unsigned ID) const {
1976 const DataLayout *DL = TM.getDataLayout();
1977 return OutContext.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix()) +
1981 /// GetTempSymbol - Return an assembler temporary label with the specified
1983 MCSymbol *AsmPrinter::GetTempSymbol(Twine Name) const {
1984 const DataLayout *DL = TM.getDataLayout();
1985 return OutContext.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix())+
1990 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
1991 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
1994 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
1995 return MMI->getAddrLabelSymbol(BB);
1998 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1999 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
2000 const DataLayout *DL = TM.getDataLayout();
2001 return OutContext.GetOrCreateSymbol
2002 (Twine(DL->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
2003 + "_" + Twine(CPID));
2006 /// GetJTISymbol - Return the symbol for the specified jump table entry.
2007 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
2008 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
2011 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
2012 /// FIXME: privatize to AsmPrinter.
2013 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
2014 const DataLayout *DL = TM.getDataLayout();
2015 return OutContext.GetOrCreateSymbol
2016 (Twine(DL->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
2017 Twine(UID) + "_set_" + Twine(MBBID));
2020 MCSymbol *AsmPrinter::getSymbolWithGlobalValueBase(const GlobalValue *GV,
2021 StringRef Suffix) const {
2022 return getObjFileLowering().getSymbolWithGlobalValueBase(GV, Suffix, *Mang,
2026 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
2028 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
2029 SmallString<60> NameStr;
2030 Mang->getNameWithPrefix(NameStr, Sym);
2031 return OutContext.GetOrCreateSymbol(NameStr.str());
2036 /// PrintParentLoopComment - Print comments about parent loops of this one.
2037 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2038 unsigned FunctionNumber) {
2039 if (Loop == 0) return;
2040 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
2041 OS.indent(Loop->getLoopDepth()*2)
2042 << "Parent Loop BB" << FunctionNumber << "_"
2043 << Loop->getHeader()->getNumber()
2044 << " Depth=" << Loop->getLoopDepth() << '\n';
2048 /// PrintChildLoopComment - Print comments about child loops within
2049 /// the loop for this basic block, with nesting.
2050 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2051 unsigned FunctionNumber) {
2052 // Add child loop information
2053 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
2054 OS.indent((*CL)->getLoopDepth()*2)
2055 << "Child Loop BB" << FunctionNumber << "_"
2056 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
2058 PrintChildLoopComment(OS, *CL, FunctionNumber);
2062 /// emitBasicBlockLoopComments - Pretty-print comments for basic blocks.
2063 static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
2064 const MachineLoopInfo *LI,
2065 const AsmPrinter &AP) {
2066 // Add loop depth information
2067 const MachineLoop *Loop = LI->getLoopFor(&MBB);
2068 if (Loop == 0) return;
2070 MachineBasicBlock *Header = Loop->getHeader();
2071 assert(Header && "No header for loop");
2073 // If this block is not a loop header, just print out what is the loop header
2075 if (Header != &MBB) {
2076 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
2077 Twine(AP.getFunctionNumber())+"_" +
2078 Twine(Loop->getHeader()->getNumber())+
2079 " Depth="+Twine(Loop->getLoopDepth()));
2083 // Otherwise, it is a loop header. Print out information about child and
2085 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
2087 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
2090 OS.indent(Loop->getLoopDepth()*2-2);
2095 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
2097 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
2101 /// EmitBasicBlockStart - This method prints the label for the specified
2102 /// MachineBasicBlock, an alignment (if present) and a comment describing
2103 /// it if appropriate.
2104 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
2105 // Emit an alignment directive for this block, if needed.
2106 if (unsigned Align = MBB->getAlignment())
2107 EmitAlignment(Align);
2109 // If the block has its address taken, emit any labels that were used to
2110 // reference the block. It is possible that there is more than one label
2111 // here, because multiple LLVM BB's may have been RAUW'd to this block after
2112 // the references were generated.
2113 if (MBB->hasAddressTaken()) {
2114 const BasicBlock *BB = MBB->getBasicBlock();
2116 OutStreamer.AddComment("Block address taken");
2118 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
2120 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
2121 OutStreamer.EmitLabel(Syms[i]);
2124 // Print some verbose block comments.
2126 if (const BasicBlock *BB = MBB->getBasicBlock())
2128 OutStreamer.AddComment("%" + BB->getName());
2129 emitBasicBlockLoopComments(*MBB, LI, *this);
2132 // Print the main label for the block.
2133 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
2135 // NOTE: Want this comment at start of line, don't emit with AddComment.
2136 OutStreamer.emitRawComment(" BB#" + Twine(MBB->getNumber()) + ":", false);
2139 OutStreamer.EmitLabel(MBB->getSymbol());
2143 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility,
2144 bool IsDefinition) const {
2145 MCSymbolAttr Attr = MCSA_Invalid;
2147 switch (Visibility) {
2149 case GlobalValue::HiddenVisibility:
2151 Attr = MAI->getHiddenVisibilityAttr();
2153 Attr = MAI->getHiddenDeclarationVisibilityAttr();
2155 case GlobalValue::ProtectedVisibility:
2156 Attr = MAI->getProtectedVisibilityAttr();
2160 if (Attr != MCSA_Invalid)
2161 OutStreamer.EmitSymbolAttribute(Sym, Attr);
2164 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
2165 /// exactly one predecessor and the control transfer mechanism between
2166 /// the predecessor and this block is a fall-through.
2168 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
2169 // If this is a landing pad, it isn't a fall through. If it has no preds,
2170 // then nothing falls through to it.
2171 if (MBB->isLandingPad() || MBB->pred_empty())
2174 // If there isn't exactly one predecessor, it can't be a fall through.
2175 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
2177 if (PI2 != MBB->pred_end())
2180 // The predecessor has to be immediately before this block.
2181 MachineBasicBlock *Pred = *PI;
2183 if (!Pred->isLayoutSuccessor(MBB))
2186 // If the block is completely empty, then it definitely does fall through.
2190 // Check the terminators in the previous blocks
2191 for (MachineBasicBlock::iterator II = Pred->getFirstTerminator(),
2192 IE = Pred->end(); II != IE; ++II) {
2193 MachineInstr &MI = *II;
2195 // If it is not a simple branch, we are in a table somewhere.
2196 if (!MI.isBranch() || MI.isIndirectBranch())
2199 // If we are the operands of one of the branches, this is not a fall
2200 // through. Note that targets with delay slots will usually bundle
2201 // terminators with the delay slot instruction.
2202 for (ConstMIBundleOperands OP(&MI); OP.isValid(); ++OP) {
2205 if (OP->isMBB() && OP->getMBB() == MBB)
2215 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
2216 if (!S->usesMetadata())
2219 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
2220 gcp_map_type::iterator GCPI = GCMap.find(S);
2221 if (GCPI != GCMap.end())
2222 return GCPI->second;
2224 const char *Name = S->getName().c_str();
2226 for (GCMetadataPrinterRegistry::iterator
2227 I = GCMetadataPrinterRegistry::begin(),
2228 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
2229 if (strcmp(Name, I->getName()) == 0) {
2230 GCMetadataPrinter *GMP = I->instantiate();
2232 GCMap.insert(std::make_pair(S, GMP));
2236 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));
2239 /// Pin vtable to this file.
2240 AsmPrinterHandler::~AsmPrinterHandler() {}