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 "llvm/Assembly/Writer.h"
17 #include "llvm/DerivedTypes.h"
18 #include "llvm/Constants.h"
19 #include "llvm/Module.h"
20 #include "llvm/CodeGen/DwarfWriter.h"
21 #include "llvm/CodeGen/GCMetadataPrinter.h"
22 #include "llvm/CodeGen/MachineConstantPool.h"
23 #include "llvm/CodeGen/MachineFrameInfo.h"
24 #include "llvm/CodeGen/MachineFunction.h"
25 #include "llvm/CodeGen/MachineJumpTableInfo.h"
26 #include "llvm/CodeGen/MachineLoopInfo.h"
27 #include "llvm/CodeGen/MachineModuleInfo.h"
28 #include "llvm/Analysis/ConstantFolding.h"
29 #include "llvm/Analysis/DebugInfo.h"
30 #include "llvm/MC/MCContext.h"
31 #include "llvm/MC/MCExpr.h"
32 #include "llvm/MC/MCInst.h"
33 #include "llvm/MC/MCSection.h"
34 #include "llvm/MC/MCStreamer.h"
35 #include "llvm/MC/MCSymbol.h"
36 #include "llvm/MC/MCAsmInfo.h"
37 #include "llvm/Target/Mangler.h"
38 #include "llvm/Target/TargetData.h"
39 #include "llvm/Target/TargetInstrInfo.h"
40 #include "llvm/Target/TargetLowering.h"
41 #include "llvm/Target/TargetLoweringObjectFile.h"
42 #include "llvm/Target/TargetOptions.h"
43 #include "llvm/Target/TargetRegisterInfo.h"
44 #include "llvm/ADT/SmallPtrSet.h"
45 #include "llvm/ADT/SmallString.h"
46 #include "llvm/ADT/Statistic.h"
47 #include "llvm/Support/CommandLine.h"
48 #include "llvm/Support/Debug.h"
49 #include "llvm/Support/ErrorHandling.h"
50 #include "llvm/Support/Format.h"
51 #include "llvm/Support/FormattedStream.h"
55 STATISTIC(EmittedInsts, "Number of machine instrs printed");
57 char AsmPrinter::ID = 0;
59 AsmPrinter::AsmPrinter(formatted_raw_ostream &o, TargetMachine &tm,
61 : MachineFunctionPass(&ID), O(o),
62 TM(tm), MAI(tm.getMCAsmInfo()), TRI(tm.getRegisterInfo()),
63 OutContext(Streamer.getContext()),
64 OutStreamer(Streamer),
65 LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {
67 VerboseAsm = Streamer.isVerboseAsm();
70 AsmPrinter::~AsmPrinter() {
71 for (gcp_iterator I = GCMetadataPrinters.begin(),
72 E = GCMetadataPrinters.end(); I != E; ++I)
78 /// getFunctionNumber - Return a unique ID for the current function.
80 unsigned AsmPrinter::getFunctionNumber() const {
81 return MF->getFunctionNumber();
84 TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
85 return TM.getTargetLowering()->getObjFileLowering();
88 /// getCurrentSection() - Return the current section we are emitting to.
89 const MCSection *AsmPrinter::getCurrentSection() const {
90 return OutStreamer.getCurrentSection();
94 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
96 MachineFunctionPass::getAnalysisUsage(AU);
97 AU.addRequired<MachineModuleInfo>();
98 AU.addRequired<GCModuleInfo>();
100 AU.addRequired<MachineLoopInfo>();
103 bool AsmPrinter::doInitialization(Module &M) {
104 MMI = &getAnalysis<MachineModuleInfo>();
105 MMI->AnalyzeModule(M);
107 // Initialize TargetLoweringObjectFile.
108 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
109 .Initialize(OutContext, TM);
111 Mang = new Mangler(OutContext, *TM.getTargetData());
113 // Allow the target to emit any magic that it wants at the start of the file.
114 EmitStartOfAsmFile(M);
116 // Very minimal debug info. It is ignored if we emit actual debug info. If we
117 // don't, this at least helps the user find where a global came from.
118 if (MAI->hasSingleParameterDotFile()) {
120 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
123 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
124 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
125 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
126 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
127 MP->beginAssembly(O, *this, *MAI);
129 // Emit module-level inline asm if it exists.
130 if (!M.getModuleInlineAsm().empty()) {
131 OutStreamer.AddComment("Start of file scope inline assembly");
132 OutStreamer.AddBlankLine();
133 EmitInlineAsm(M.getModuleInlineAsm());
134 OutStreamer.AddComment("End of file scope inline assembly");
135 OutStreamer.AddBlankLine();
138 DW = getAnalysisIfAvailable<DwarfWriter>();
140 DW->BeginModule(&M, MMI, O, this, MAI);
145 void AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const {
146 switch ((GlobalValue::LinkageTypes)Linkage) {
147 case GlobalValue::CommonLinkage:
148 case GlobalValue::LinkOnceAnyLinkage:
149 case GlobalValue::LinkOnceODRLinkage:
150 case GlobalValue::WeakAnyLinkage:
151 case GlobalValue::WeakODRLinkage:
152 case GlobalValue::LinkerPrivateLinkage:
153 if (MAI->getWeakDefDirective() != 0) {
155 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
156 // .weak_definition _foo
157 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
158 } else if (const char *LinkOnce = MAI->getLinkOnceDirective()) {
160 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
161 // FIXME: linkonce should be a section attribute, handled by COFF Section
163 // http://sourceware.org/binutils/docs-2.20/as/Linkonce.html#Linkonce
165 // FIXME: It would be nice to use .linkonce samesize for non-common
167 OutStreamer.EmitRawText(StringRef(LinkOnce));
170 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
173 case GlobalValue::DLLExportLinkage:
174 case GlobalValue::AppendingLinkage:
175 // FIXME: appending linkage variables should go into a section of
176 // their name or something. For now, just emit them as external.
177 case GlobalValue::ExternalLinkage:
178 // If external or appending, declare as a global symbol.
180 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
182 case GlobalValue::PrivateLinkage:
183 case GlobalValue::InternalLinkage:
186 llvm_unreachable("Unknown linkage type!");
191 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
192 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
193 if (!GV->hasInitializer()) // External globals require no code.
196 // Check to see if this is a special global used by LLVM, if so, emit it.
197 if (EmitSpecialLLVMGlobal(GV))
200 MCSymbol *GVSym = Mang->getSymbol(GV);
201 EmitVisibility(GVSym, GV->getVisibility());
203 if (MAI->hasDotTypeDotSizeDirective())
204 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
206 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
208 const TargetData *TD = TM.getTargetData();
209 unsigned Size = TD->getTypeAllocSize(GV->getType()->getElementType());
210 unsigned AlignLog = TD->getPreferredAlignmentLog(GV);
212 // Handle common and BSS local symbols (.lcomm).
213 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
214 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
217 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
218 /*PrintType=*/false, GV->getParent());
219 OutStreamer.GetCommentOS() << '\n';
222 // Handle common symbols.
223 if (GVKind.isCommon()) {
225 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
229 // Handle local BSS symbols.
230 if (MAI->hasMachoZeroFillDirective()) {
231 const MCSection *TheSection =
232 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
233 // .zerofill __DATA, __bss, _foo, 400, 5
234 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
238 if (MAI->hasLCOMMDirective()) {
240 OutStreamer.EmitLocalCommonSymbol(GVSym, Size);
245 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
247 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
251 const MCSection *TheSection =
252 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
254 // Handle the zerofill directive on darwin, which is a special form of BSS
256 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
258 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
259 // .zerofill __DATA, __common, _foo, 400, 5
260 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
264 OutStreamer.SwitchSection(TheSection);
266 EmitLinkage(GV->getLinkage(), GVSym);
267 EmitAlignment(AlignLog, GV);
270 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
271 /*PrintType=*/false, GV->getParent());
272 OutStreamer.GetCommentOS() << '\n';
274 OutStreamer.EmitLabel(GVSym);
276 EmitGlobalConstant(GV->getInitializer());
278 if (MAI->hasDotTypeDotSizeDirective())
280 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
282 OutStreamer.AddBlankLine();
285 /// EmitFunctionHeader - This method emits the header for the current
287 void AsmPrinter::EmitFunctionHeader() {
288 // Print out constants referenced by the function
291 // Print the 'header' of function.
292 const Function *F = MF->getFunction();
294 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
295 EmitVisibility(CurrentFnSym, F->getVisibility());
297 EmitLinkage(F->getLinkage(), CurrentFnSym);
298 EmitAlignment(MF->getAlignment(), F);
300 if (MAI->hasDotTypeDotSizeDirective())
301 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
304 WriteAsOperand(OutStreamer.GetCommentOS(), F,
305 /*PrintType=*/false, F->getParent());
306 OutStreamer.GetCommentOS() << '\n';
309 // Emit the CurrentFnSym. This is a virtual function to allow targets to
310 // do their wild and crazy things as required.
311 EmitFunctionEntryLabel();
313 // If the function had address-taken blocks that got deleted, then we have
314 // references to the dangling symbols. Emit them at the start of the function
315 // so that we don't get references to undefined symbols.
316 std::vector<MCSymbol*> DeadBlockSyms;
317 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
318 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
319 OutStreamer.AddComment("Address taken block that was later removed");
320 OutStreamer.EmitLabel(DeadBlockSyms[i]);
323 // Add some workaround for linkonce linkage on Cygwin\MinGW.
324 if (MAI->getLinkOnceDirective() != 0 &&
325 (F->hasLinkOnceLinkage() || F->hasWeakLinkage())) {
326 // FIXME: What is this?
328 OutContext.GetOrCreateSymbol(Twine("Lllvm$workaround$fake$stub$")+
329 CurrentFnSym->getName());
330 OutStreamer.EmitLabel(FakeStub);
333 // Emit pre-function debug and/or EH information.
334 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
335 DW->BeginFunction(MF);
338 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
339 /// function. This can be overridden by targets as required to do custom stuff.
340 void AsmPrinter::EmitFunctionEntryLabel() {
341 OutStreamer.EmitLabel(CurrentFnSym);
345 /// EmitComments - Pretty-print comments for instructions.
346 static void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
347 const MachineFunction *MF = MI.getParent()->getParent();
348 const TargetMachine &TM = MF->getTarget();
350 DebugLoc DL = MI.getDebugLoc();
351 if (!DL.isUnknown()) { // Print source line info.
352 DIScope Scope(DL.getScope(MF->getFunction()->getContext()));
353 // Omit the directory, because it's likely to be long and uninteresting.
355 CommentOS << Scope.getFilename();
357 CommentOS << "<unknown>";
358 CommentOS << ':' << DL.getLine();
359 if (DL.getCol() != 0)
360 CommentOS << ':' << DL.getCol();
364 // Check for spills and reloads
367 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
369 // We assume a single instruction only has a spill or reload, not
371 const MachineMemOperand *MMO;
372 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
373 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
374 MMO = *MI.memoperands_begin();
375 CommentOS << MMO->getSize() << "-byte Reload\n";
377 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
378 if (FrameInfo->isSpillSlotObjectIndex(FI))
379 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
380 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
381 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
382 MMO = *MI.memoperands_begin();
383 CommentOS << MMO->getSize() << "-byte Spill\n";
385 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
386 if (FrameInfo->isSpillSlotObjectIndex(FI))
387 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
390 // Check for spill-induced copies
391 unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
392 if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg,
393 SrcSubIdx, DstSubIdx)) {
394 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
395 CommentOS << " Reload Reuse\n";
401 /// EmitFunctionBody - This method emits the body and trailer for a
403 void AsmPrinter::EmitFunctionBody() {
404 // Emit target-specific gunk before the function body.
405 EmitFunctionBodyStart();
407 // Print out code for the function.
408 bool HasAnyRealCode = false;
409 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
411 // Print a label for the basic block.
412 EmitBasicBlockStart(I);
413 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
415 // Print the assembly for the instruction.
417 HasAnyRealCode = true;
421 // FIXME: Clean up processDebugLoc.
422 processDebugLoc(II, true);
425 EmitComments(*II, OutStreamer.GetCommentOS());
427 switch (II->getOpcode()) {
428 case TargetOpcode::DBG_LABEL:
429 case TargetOpcode::EH_LABEL:
430 case TargetOpcode::GC_LABEL:
433 case TargetOpcode::INLINEASM:
436 case TargetOpcode::IMPLICIT_DEF:
437 printImplicitDef(II);
439 case TargetOpcode::KILL:
447 // FIXME: Clean up processDebugLoc.
448 processDebugLoc(II, false);
452 // If the function is empty and the object file uses .subsections_via_symbols,
453 // then we need to emit *something* to the function body to prevent the
454 // labels from collapsing together. Just emit a 0 byte.
455 if (MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)
456 OutStreamer.EmitIntValue(0, 1, 0/*addrspace*/);
458 // Emit target-specific gunk after the function body.
459 EmitFunctionBodyEnd();
461 // If the target wants a .size directive for the size of the function, emit
463 if (MAI->hasDotTypeDotSizeDirective()) {
464 // Create a symbol for the end of function, so we can get the size as
465 // difference between the function label and the temp label.
466 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
467 OutStreamer.EmitLabel(FnEndLabel);
469 const MCExpr *SizeExp =
470 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
471 MCSymbolRefExpr::Create(CurrentFnSym, OutContext),
473 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
476 // Emit post-function debug information.
477 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
480 // Print out jump tables referenced by the function.
483 OutStreamer.AddBlankLine();
487 bool AsmPrinter::doFinalization(Module &M) {
488 // Emit global variables.
489 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
491 EmitGlobalVariable(I);
493 // Emit final debug information.
494 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
497 // If the target wants to know about weak references, print them all.
498 if (MAI->getWeakRefDirective()) {
499 // FIXME: This is not lazy, it would be nice to only print weak references
500 // to stuff that is actually used. Note that doing so would require targets
501 // to notice uses in operands (due to constant exprs etc). This should
502 // happen with the MC stuff eventually.
504 // Print out module-level global variables here.
505 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
507 if (!I->hasExternalWeakLinkage()) continue;
508 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
511 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
512 if (!I->hasExternalWeakLinkage()) continue;
513 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
517 if (MAI->hasSetDirective()) {
518 OutStreamer.AddBlankLine();
519 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
521 MCSymbol *Name = Mang->getSymbol(I);
523 const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
524 MCSymbol *Target = Mang->getSymbol(GV);
526 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
527 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
528 else if (I->hasWeakLinkage())
529 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
531 assert(I->hasLocalLinkage() && "Invalid alias linkage");
533 EmitVisibility(Name, I->getVisibility());
535 // Emit the directives as assignments aka .set:
536 OutStreamer.EmitAssignment(Name,
537 MCSymbolRefExpr::Create(Target, OutContext));
541 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
542 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
543 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
544 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
545 MP->finishAssembly(O, *this, *MAI);
547 // If we don't have any trampolines, then we don't require stack memory
548 // to be executable. Some targets have a directive to declare this.
549 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
550 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
551 if (MCSection *S = MAI->getNonexecutableStackSection(OutContext))
552 OutStreamer.SwitchSection(S);
554 // Allow the target to emit any magic that it wants at the end of the file,
555 // after everything else has gone out.
558 delete Mang; Mang = 0;
561 OutStreamer.Finish();
565 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
567 // Get the function symbol.
568 CurrentFnSym = Mang->getSymbol(MF.getFunction());
571 LI = &getAnalysis<MachineLoopInfo>();
575 // SectionCPs - Keep track the alignment, constpool entries per Section.
579 SmallVector<unsigned, 4> CPEs;
580 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
584 /// EmitConstantPool - Print to the current output stream assembly
585 /// representations of the constants in the constant pool MCP. This is
586 /// used to print out constants which have been "spilled to memory" by
587 /// the code generator.
589 void AsmPrinter::EmitConstantPool() {
590 const MachineConstantPool *MCP = MF->getConstantPool();
591 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
592 if (CP.empty()) return;
594 // Calculate sections for constant pool entries. We collect entries to go into
595 // the same section together to reduce amount of section switch statements.
596 SmallVector<SectionCPs, 4> CPSections;
597 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
598 const MachineConstantPoolEntry &CPE = CP[i];
599 unsigned Align = CPE.getAlignment();
602 switch (CPE.getRelocationInfo()) {
603 default: llvm_unreachable("Unknown section kind");
604 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
606 Kind = SectionKind::getReadOnlyWithRelLocal();
609 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
610 case 4: Kind = SectionKind::getMergeableConst4(); break;
611 case 8: Kind = SectionKind::getMergeableConst8(); break;
612 case 16: Kind = SectionKind::getMergeableConst16();break;
613 default: Kind = SectionKind::getMergeableConst(); break;
617 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
619 // The number of sections are small, just do a linear search from the
620 // last section to the first.
622 unsigned SecIdx = CPSections.size();
623 while (SecIdx != 0) {
624 if (CPSections[--SecIdx].S == S) {
630 SecIdx = CPSections.size();
631 CPSections.push_back(SectionCPs(S, Align));
634 if (Align > CPSections[SecIdx].Alignment)
635 CPSections[SecIdx].Alignment = Align;
636 CPSections[SecIdx].CPEs.push_back(i);
639 // Now print stuff into the calculated sections.
640 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
641 OutStreamer.SwitchSection(CPSections[i].S);
642 EmitAlignment(Log2_32(CPSections[i].Alignment));
645 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
646 unsigned CPI = CPSections[i].CPEs[j];
647 MachineConstantPoolEntry CPE = CP[CPI];
649 // Emit inter-object padding for alignment.
650 unsigned AlignMask = CPE.getAlignment() - 1;
651 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
652 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/);
654 const Type *Ty = CPE.getType();
655 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
657 // Emit the label with a comment on it.
659 OutStreamer.GetCommentOS() << "constant pool ";
660 WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(),
661 MF->getFunction()->getParent());
662 OutStreamer.GetCommentOS() << '\n';
664 OutStreamer.EmitLabel(GetCPISymbol(CPI));
666 if (CPE.isMachineConstantPoolEntry())
667 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
669 EmitGlobalConstant(CPE.Val.ConstVal);
674 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
675 /// by the current function to the current output stream.
677 void AsmPrinter::EmitJumpTableInfo() {
678 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
679 if (MJTI == 0) return;
680 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
681 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
682 if (JT.empty()) return;
684 // Pick the directive to use to print the jump table entries, and switch to
685 // the appropriate section.
686 const Function *F = MF->getFunction();
687 bool JTInDiffSection = false;
688 if (// In PIC mode, we need to emit the jump table to the same section as the
689 // function body itself, otherwise the label differences won't make sense.
690 // FIXME: Need a better predicate for this: what about custom entries?
691 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
692 // We should also do if the section name is NULL or function is declared
693 // in discardable section
694 // FIXME: this isn't the right predicate, should be based on the MCSection
696 F->isWeakForLinker()) {
697 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
699 // Otherwise, drop it in the readonly section.
700 const MCSection *ReadOnlySection =
701 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
702 OutStreamer.SwitchSection(ReadOnlySection);
703 JTInDiffSection = true;
706 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData())));
708 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
709 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
711 // If this jump table was deleted, ignore it.
712 if (JTBBs.empty()) continue;
714 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
715 // .set directive for each unique entry. This reduces the number of
716 // relocations the assembler will generate for the jump table.
717 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
718 MAI->hasSetDirective()) {
719 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
720 const TargetLowering *TLI = TM.getTargetLowering();
721 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
722 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
723 const MachineBasicBlock *MBB = JTBBs[ii];
724 if (!EmittedSets.insert(MBB)) continue;
726 // .set LJTSet, LBB32-base
728 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
729 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
730 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
734 // On some targets (e.g. Darwin) we want to emit two consequtive labels
735 // before each jump table. The first label is never referenced, but tells
736 // the assembler and linker the extents of the jump table object. The
737 // second label is actually referenced by the code.
738 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
739 // FIXME: This doesn't have to have any specific name, just any randomly
740 // named and numbered 'l' label would work. Simplify GetJTISymbol.
741 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
743 OutStreamer.EmitLabel(GetJTISymbol(JTI));
745 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
746 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
750 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
752 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
753 const MachineBasicBlock *MBB,
754 unsigned UID) const {
755 const MCExpr *Value = 0;
756 switch (MJTI->getEntryKind()) {
757 case MachineJumpTableInfo::EK_Inline:
758 llvm_unreachable("Cannot emit EK_Inline jump table entry"); break;
759 case MachineJumpTableInfo::EK_Custom32:
760 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
763 case MachineJumpTableInfo::EK_BlockAddress:
764 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
766 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
768 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
769 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
770 // with a relocation as gp-relative, e.g.:
772 MCSymbol *MBBSym = MBB->getSymbol();
773 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
777 case MachineJumpTableInfo::EK_LabelDifference32: {
778 // EK_LabelDifference32 - Each entry is the address of the block minus
779 // the address of the jump table. This is used for PIC jump tables where
780 // gprel32 is not supported. e.g.:
781 // .word LBB123 - LJTI1_2
782 // If the .set directive is supported, this is emitted as:
783 // .set L4_5_set_123, LBB123 - LJTI1_2
784 // .word L4_5_set_123
786 // If we have emitted set directives for the jump table entries, print
787 // them rather than the entries themselves. If we're emitting PIC, then
788 // emit the table entries as differences between two text section labels.
789 if (MAI->hasSetDirective()) {
790 // If we used .set, reference the .set's symbol.
791 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
795 // Otherwise, use the difference as the jump table entry.
796 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
797 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
798 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
803 assert(Value && "Unknown entry kind!");
805 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData());
806 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0);
810 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
811 /// special global used by LLVM. If so, emit it and return true, otherwise
812 /// do nothing and return false.
813 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
814 if (GV->getName() == "llvm.used") {
815 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
816 EmitLLVMUsedList(GV->getInitializer());
820 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
821 if (GV->getSection() == "llvm.metadata" ||
822 GV->hasAvailableExternallyLinkage())
825 if (!GV->hasAppendingLinkage()) return false;
827 assert(GV->hasInitializer() && "Not a special LLVM global!");
829 const TargetData *TD = TM.getTargetData();
830 unsigned Align = Log2_32(TD->getPointerPrefAlignment());
831 if (GV->getName() == "llvm.global_ctors") {
832 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection());
833 EmitAlignment(Align, 0);
834 EmitXXStructorList(GV->getInitializer());
836 if (TM.getRelocationModel() == Reloc::Static &&
837 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
838 StringRef Sym(".constructors_used");
839 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
845 if (GV->getName() == "llvm.global_dtors") {
846 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection());
847 EmitAlignment(Align, 0);
848 EmitXXStructorList(GV->getInitializer());
850 if (TM.getRelocationModel() == Reloc::Static &&
851 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
852 StringRef Sym(".destructors_used");
853 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
862 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
863 /// global in the specified llvm.used list for which emitUsedDirectiveFor
864 /// is true, as being used with this directive.
865 void AsmPrinter::EmitLLVMUsedList(Constant *List) {
866 // Should be an array of 'i8*'.
867 ConstantArray *InitList = dyn_cast<ConstantArray>(List);
868 if (InitList == 0) return;
870 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
871 const GlobalValue *GV =
872 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
873 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
874 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip);
878 /// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the
879 /// function pointers, ignoring the init priority.
880 void AsmPrinter::EmitXXStructorList(Constant *List) {
881 // Should be an array of '{ int, void ()* }' structs. The first value is the
882 // init priority, which we ignore.
883 if (!isa<ConstantArray>(List)) return;
884 ConstantArray *InitList = cast<ConstantArray>(List);
885 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
886 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
887 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs.
889 if (CS->getOperand(1)->isNullValue())
890 return; // Found a null terminator, exit printing.
891 // Emit the function pointer.
892 EmitGlobalConstant(CS->getOperand(1));
896 /// EmitInlineAsm - Emit a blob of inline asm to the output streamer.
897 void AsmPrinter::EmitInlineAsm(StringRef Str) const {
898 assert(!Str.empty() && "Can't emit empty inline asm block");
900 // If the output streamer is actually a .s file, just emit the blob textually.
901 // This is useful in case the asm parser doesn't handle something but the
902 // system assembler does.
903 if (OutStreamer.hasRawTextSupport()) {
904 OutStreamer.EmitRawText(Str);
908 errs() << "Inline asm not supported by this streamer!\n";
912 //===--------------------------------------------------------------------===//
913 // Emission and print routines
916 /// EmitInt8 - Emit a byte directive and value.
918 void AsmPrinter::EmitInt8(int Value) const {
919 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/);
922 /// EmitInt16 - Emit a short directive and value.
924 void AsmPrinter::EmitInt16(int Value) const {
925 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/);
928 /// EmitInt32 - Emit a long directive and value.
930 void AsmPrinter::EmitInt32(int Value) const {
931 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/);
934 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
935 /// in bytes of the directive is specified by Size and Hi/Lo specify the
936 /// labels. This implicitly uses .set if it is available.
937 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
938 unsigned Size) const {
939 // Get the Hi-Lo expression.
941 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
942 MCSymbolRefExpr::Create(Lo, OutContext),
945 if (!MAI->hasSetDirective()) {
946 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/);
950 // Otherwise, emit with .set (aka assignment).
952 OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) +
953 "set" + Twine(SetCounter++));
954 OutStreamer.EmitAssignment(SetLabel, Diff);
955 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/);
959 //===----------------------------------------------------------------------===//
961 // EmitAlignment - Emit an alignment directive to the specified power of
962 // two boundary. For example, if you pass in 3 here, you will get an 8
963 // byte alignment. If a global value is specified, and if that global has
964 // an explicit alignment requested, it will unconditionally override the
965 // alignment request. However, if ForcedAlignBits is specified, this value
966 // has final say: the ultimate alignment will be the max of ForcedAlignBits
967 // and the alignment computed with NumBits and the global.
971 // if (GV && GV->hasalignment) Align = GV->getalignment();
972 // Align = std::max(Align, ForcedAlignBits);
974 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
975 unsigned ForcedAlignBits,
976 bool UseFillExpr) const {
977 if (GV && GV->getAlignment())
978 NumBits = Log2_32(GV->getAlignment());
979 NumBits = std::max(NumBits, ForcedAlignBits);
981 if (NumBits == 0) return; // No need to emit alignment.
983 if (getCurrentSection()->getKind().isText())
984 OutStreamer.EmitCodeAlignment(1 << NumBits);
986 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
989 /// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
991 static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) {
992 MCContext &Ctx = AP.OutContext;
994 if (CV->isNullValue() || isa<UndefValue>(CV))
995 return MCConstantExpr::Create(0, Ctx);
997 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
998 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1000 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1001 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx);
1002 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1003 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1005 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1007 llvm_unreachable("Unknown constant value to lower!");
1008 return MCConstantExpr::Create(0, Ctx);
1011 switch (CE->getOpcode()) {
1013 // If the code isn't optimized, there may be outstanding folding
1014 // opportunities. Attempt to fold the expression using TargetData as a
1015 // last resort before giving up.
1017 ConstantFoldConstantExpression(CE, AP.TM.getTargetData()))
1019 return LowerConstant(C, AP);
1023 llvm_unreachable("FIXME: Don't support this constant expr");
1024 case Instruction::GetElementPtr: {
1025 const TargetData &TD = *AP.TM.getTargetData();
1026 // Generate a symbolic expression for the byte address
1027 const Constant *PtrVal = CE->getOperand(0);
1028 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
1029 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0],
1032 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
1036 // Truncate/sext the offset to the pointer size.
1037 if (TD.getPointerSizeInBits() != 64) {
1038 int SExtAmount = 64-TD.getPointerSizeInBits();
1039 Offset = (Offset << SExtAmount) >> SExtAmount;
1042 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1046 case Instruction::Trunc:
1047 // We emit the value and depend on the assembler to truncate the generated
1048 // expression properly. This is important for differences between
1049 // blockaddress labels. Since the two labels are in the same function, it
1050 // is reasonable to treat their delta as a 32-bit value.
1052 case Instruction::BitCast:
1053 return LowerConstant(CE->getOperand(0), AP);
1055 case Instruction::IntToPtr: {
1056 const TargetData &TD = *AP.TM.getTargetData();
1057 // Handle casts to pointers by changing them into casts to the appropriate
1058 // integer type. This promotes constant folding and simplifies this code.
1059 Constant *Op = CE->getOperand(0);
1060 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
1062 return LowerConstant(Op, AP);
1065 case Instruction::PtrToInt: {
1066 const TargetData &TD = *AP.TM.getTargetData();
1067 // Support only foldable casts to/from pointers that can be eliminated by
1068 // changing the pointer to the appropriately sized integer type.
1069 Constant *Op = CE->getOperand(0);
1070 const Type *Ty = CE->getType();
1072 const MCExpr *OpExpr = LowerConstant(Op, AP);
1074 // We can emit the pointer value into this slot if the slot is an
1075 // integer slot equal to the size of the pointer.
1076 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
1079 // Otherwise the pointer is smaller than the resultant integer, mask off
1080 // the high bits so we are sure to get a proper truncation if the input is
1082 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
1083 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1084 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1087 // The MC library also has a right-shift operator, but it isn't consistently
1088 // signed or unsigned between different targets.
1089 case Instruction::Add:
1090 case Instruction::Sub:
1091 case Instruction::Mul:
1092 case Instruction::SDiv:
1093 case Instruction::SRem:
1094 case Instruction::Shl:
1095 case Instruction::And:
1096 case Instruction::Or:
1097 case Instruction::Xor: {
1098 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP);
1099 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP);
1100 switch (CE->getOpcode()) {
1101 default: llvm_unreachable("Unknown binary operator constant cast expr");
1102 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1103 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1104 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1105 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1106 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1107 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1108 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1109 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1110 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1116 static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
1118 if (AddrSpace != 0 || !CA->isString()) {
1119 // Not a string. Print the values in successive locations
1120 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1121 AP.EmitGlobalConstant(CA->getOperand(i), AddrSpace);
1125 // Otherwise, it can be emitted as .ascii.
1126 SmallVector<char, 128> TmpVec;
1127 TmpVec.reserve(CA->getNumOperands());
1128 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1129 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
1131 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace);
1134 static void EmitGlobalConstantVector(const ConstantVector *CV,
1135 unsigned AddrSpace, AsmPrinter &AP) {
1136 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1137 AP.EmitGlobalConstant(CV->getOperand(i), AddrSpace);
1140 static void EmitGlobalConstantStruct(const ConstantStruct *CS,
1141 unsigned AddrSpace, AsmPrinter &AP) {
1142 // Print the fields in successive locations. Pad to align if needed!
1143 const TargetData *TD = AP.TM.getTargetData();
1144 unsigned Size = TD->getTypeAllocSize(CS->getType());
1145 const StructLayout *Layout = TD->getStructLayout(CS->getType());
1146 uint64_t SizeSoFar = 0;
1147 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1148 const Constant *Field = CS->getOperand(i);
1150 // Check if padding is needed and insert one or more 0s.
1151 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
1152 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1153 - Layout->getElementOffset(i)) - FieldSize;
1154 SizeSoFar += FieldSize + PadSize;
1156 // Now print the actual field value.
1157 AP.EmitGlobalConstant(Field, AddrSpace);
1159 // Insert padding - this may include padding to increase the size of the
1160 // current field up to the ABI size (if the struct is not packed) as well
1161 // as padding to ensure that the next field starts at the right offset.
1162 AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
1164 assert(SizeSoFar == Layout->getSizeInBytes() &&
1165 "Layout of constant struct may be incorrect!");
1168 static void EmitGlobalConstantUnion(const ConstantUnion *CU,
1169 unsigned AddrSpace, AsmPrinter &AP) {
1170 const TargetData *TD = AP.TM.getTargetData();
1171 unsigned Size = TD->getTypeAllocSize(CU->getType());
1173 const Constant *Contents = CU->getOperand(0);
1174 unsigned FilledSize = TD->getTypeAllocSize(Contents->getType());
1176 // Print the actually filled part
1177 AP.EmitGlobalConstant(Contents, AddrSpace);
1179 // And pad with enough zeroes
1180 AP.OutStreamer.EmitZeros(Size-FilledSize, AddrSpace);
1183 static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
1185 // FP Constants are printed as integer constants to avoid losing
1187 if (CFP->getType()->isDoubleTy()) {
1188 if (AP.VerboseAsm) {
1189 double Val = CFP->getValueAPF().convertToDouble();
1190 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n';
1193 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1194 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1198 if (CFP->getType()->isFloatTy()) {
1199 if (AP.VerboseAsm) {
1200 float Val = CFP->getValueAPF().convertToFloat();
1201 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n';
1203 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1204 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace);
1208 if (CFP->getType()->isX86_FP80Ty()) {
1209 // all long double variants are printed as hex
1210 // api needed to prevent premature destruction
1211 APInt API = CFP->getValueAPF().bitcastToAPInt();
1212 const uint64_t *p = API.getRawData();
1213 if (AP.VerboseAsm) {
1214 // Convert to double so we can print the approximate val as a comment.
1215 APFloat DoubleVal = CFP->getValueAPF();
1217 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1219 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= "
1220 << DoubleVal.convertToDouble() << '\n';
1223 if (AP.TM.getTargetData()->isBigEndian()) {
1224 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1225 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1227 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1228 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1231 // Emit the tail padding for the long double.
1232 const TargetData &TD = *AP.TM.getTargetData();
1233 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
1234 TD.getTypeStoreSize(CFP->getType()), AddrSpace);
1238 assert(CFP->getType()->isPPC_FP128Ty() &&
1239 "Floating point constant type not handled");
1240 // All long double variants are printed as hex api needed to prevent
1241 // premature destruction.
1242 APInt API = CFP->getValueAPF().bitcastToAPInt();
1243 const uint64_t *p = API.getRawData();
1244 if (AP.TM.getTargetData()->isBigEndian()) {
1245 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1246 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1248 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1249 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1253 static void EmitGlobalConstantLargeInt(const ConstantInt *CI,
1254 unsigned AddrSpace, AsmPrinter &AP) {
1255 const TargetData *TD = AP.TM.getTargetData();
1256 unsigned BitWidth = CI->getBitWidth();
1257 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
1259 // We don't expect assemblers to support integer data directives
1260 // for more than 64 bits, so we emit the data in at most 64-bit
1261 // quantities at a time.
1262 const uint64_t *RawData = CI->getValue().getRawData();
1263 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1264 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1265 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1269 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1270 void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1271 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) {
1272 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1273 if (Size == 0) Size = 1; // An empty "_foo:" followed by a section is undef.
1274 return OutStreamer.EmitZeros(Size, AddrSpace);
1277 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1278 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1285 OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue());
1286 OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1289 EmitGlobalConstantLargeInt(CI, AddrSpace, *this);
1294 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1295 return EmitGlobalConstantArray(CVA, AddrSpace, *this);
1297 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1298 return EmitGlobalConstantStruct(CVS, AddrSpace, *this);
1300 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1301 return EmitGlobalConstantFP(CFP, AddrSpace, *this);
1303 if (isa<ConstantPointerNull>(CV)) {
1304 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1305 OutStreamer.EmitIntValue(0, Size, AddrSpace);
1309 if (const ConstantUnion *CVU = dyn_cast<ConstantUnion>(CV))
1310 return EmitGlobalConstantUnion(CVU, AddrSpace, *this);
1312 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1313 return EmitGlobalConstantVector(V, AddrSpace, *this);
1315 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1316 // thread the streamer with EmitValue.
1317 OutStreamer.EmitValue(LowerConstant(CV, *this),
1318 TM.getTargetData()->getTypeAllocSize(CV->getType()),
1322 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1323 // Target doesn't support this yet!
1324 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1327 /// PrintSpecial - Print information related to the specified machine instr
1328 /// that is independent of the operand, and may be independent of the instr
1329 /// itself. This can be useful for portably encoding the comment character
1330 /// or other bits of target-specific knowledge into the asmstrings. The
1331 /// syntax used is ${:comment}. Targets can override this to add support
1332 /// for their own strange codes.
1333 void AsmPrinter::PrintSpecial(const MachineInstr *MI, raw_ostream &OS,
1334 const char *Code) const {
1335 if (!strcmp(Code, "private")) {
1336 OS << MAI->getPrivateGlobalPrefix();
1337 } else if (!strcmp(Code, "comment")) {
1338 OS << MAI->getCommentString();
1339 } else if (!strcmp(Code, "uid")) {
1340 // Comparing the address of MI isn't sufficient, because machineinstrs may
1341 // be allocated to the same address across functions.
1342 const Function *ThisF = MI->getParent()->getParent()->getFunction();
1344 // If this is a new LastFn instruction, bump the counter.
1345 if (LastMI != MI || LastFn != ThisF) {
1353 raw_string_ostream Msg(msg);
1354 Msg << "Unknown special formatter '" << Code
1355 << "' for machine instr: " << *MI;
1356 llvm_report_error(Msg.str());
1360 /// processDebugLoc - Processes the debug information of each machine
1361 /// instruction's DebugLoc.
1362 void AsmPrinter::processDebugLoc(const MachineInstr *MI,
1363 bool BeforePrintingInsn) {
1364 if (!MAI || !DW || !MAI->doesSupportDebugInformation()
1365 || !DW->ShouldEmitDwarfDebug())
1368 if (!BeforePrintingInsn)
1369 // After printing instruction
1376 /// printInlineAsm - This method formats and prints the specified machine
1377 /// instruction that is an inline asm.
1378 void AsmPrinter::printInlineAsm(const MachineInstr *MI) const {
1379 assert(MI->isInlineAsm() && "printInlineAsm only works on inline asms");
1381 unsigned NumOperands = MI->getNumOperands();
1383 // Count the number of register definitions to find the asm string.
1384 unsigned NumDefs = 0;
1385 for (; MI->getOperand(NumDefs).isReg() && MI->getOperand(NumDefs).isDef();
1387 assert(NumDefs != NumOperands-1 && "No asm string?");
1389 assert(MI->getOperand(NumDefs).isSymbol() && "No asm string?");
1391 // Disassemble the AsmStr, printing out the literal pieces, the operands, etc.
1392 const char *AsmStr = MI->getOperand(NumDefs).getSymbolName();
1394 // If this asmstr is empty, just print the #APP/#NOAPP markers.
1395 // These are useful to see where empty asm's wound up.
1396 if (AsmStr[0] == 0) {
1397 if (!OutStreamer.hasRawTextSupport()) return;
1399 OutStreamer.EmitRawText(Twine("\t")+MAI->getCommentString()+
1400 MAI->getInlineAsmStart());
1401 OutStreamer.EmitRawText(Twine("\t")+MAI->getCommentString()+
1402 MAI->getInlineAsmEnd());
1406 // Emit the #APP start marker. This has to happen even if verbose-asm isn't
1407 // enabled, so we use EmitRawText.
1408 if (OutStreamer.hasRawTextSupport())
1409 OutStreamer.EmitRawText(Twine("\t")+MAI->getCommentString()+
1410 MAI->getInlineAsmStart());
1412 // Emit the inline asm to a temporary string so we can emit it through
1415 SmallString<256> StringData;
1416 raw_svector_ostream OS(StringData);
1418 raw_ostream &OS = O;
1422 // The variant of the current asmprinter.
1423 int AsmPrinterVariant = MAI->getAssemblerDialect();
1425 int CurVariant = -1; // The number of the {.|.|.} region we are in.
1426 const char *LastEmitted = AsmStr; // One past the last character emitted.
1428 while (*LastEmitted) {
1429 switch (*LastEmitted) {
1431 // Not a special case, emit the string section literally.
1432 const char *LiteralEnd = LastEmitted+1;
1433 while (*LiteralEnd && *LiteralEnd != '{' && *LiteralEnd != '|' &&
1434 *LiteralEnd != '}' && *LiteralEnd != '$' && *LiteralEnd != '\n')
1436 if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1437 OS.write(LastEmitted, LiteralEnd-LastEmitted);
1438 LastEmitted = LiteralEnd;
1442 ++LastEmitted; // Consume newline character.
1443 OS << '\n'; // Indent code with newline.
1446 ++LastEmitted; // Consume '$' character.
1450 switch (*LastEmitted) {
1451 default: Done = false; break;
1452 case '$': // $$ -> $
1453 if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1455 ++LastEmitted; // Consume second '$' character.
1457 case '(': // $( -> same as GCC's { character.
1458 ++LastEmitted; // Consume '(' character.
1459 if (CurVariant != -1) {
1460 llvm_report_error("Nested variants found in inline asm string: '"
1461 + std::string(AsmStr) + "'");
1463 CurVariant = 0; // We're in the first variant now.
1466 ++LastEmitted; // consume '|' character.
1467 if (CurVariant == -1)
1468 OS << '|'; // this is gcc's behavior for | outside a variant
1470 ++CurVariant; // We're in the next variant.
1472 case ')': // $) -> same as GCC's } char.
1473 ++LastEmitted; // consume ')' character.
1474 if (CurVariant == -1)
1475 OS << '}'; // this is gcc's behavior for } outside a variant
1482 bool HasCurlyBraces = false;
1483 if (*LastEmitted == '{') { // ${variable}
1484 ++LastEmitted; // Consume '{' character.
1485 HasCurlyBraces = true;
1488 // If we have ${:foo}, then this is not a real operand reference, it is a
1489 // "magic" string reference, just like in .td files. Arrange to call
1491 if (HasCurlyBraces && *LastEmitted == ':') {
1493 const char *StrStart = LastEmitted;
1494 const char *StrEnd = strchr(StrStart, '}');
1496 llvm_report_error(Twine("Unterminated ${:foo} operand in inline asm"
1497 " string: '") + Twine(AsmStr_ + "'"));
1499 std::string Val(StrStart, StrEnd);
1500 PrintSpecial(MI, OS, Val.c_str());
1501 LastEmitted = StrEnd+1;
1505 const char *IDStart = LastEmitted;
1508 long Val = strtol(IDStart, &IDEnd, 10); // We only accept numbers for IDs.
1509 if (!isdigit(*IDStart) || (Val == 0 && errno == EINVAL)) {
1510 llvm_report_error("Bad $ operand number in inline asm string: '"
1511 + std::string(AsmStr) + "'");
1513 LastEmitted = IDEnd;
1515 char Modifier[2] = { 0, 0 };
1517 if (HasCurlyBraces) {
1518 // If we have curly braces, check for a modifier character. This
1519 // supports syntax like ${0:u}, which correspond to "%u0" in GCC asm.
1520 if (*LastEmitted == ':') {
1521 ++LastEmitted; // Consume ':' character.
1522 if (*LastEmitted == 0) {
1523 llvm_report_error("Bad ${:} expression in inline asm string: '"
1524 + std::string(AsmStr) + "'");
1527 Modifier[0] = *LastEmitted;
1528 ++LastEmitted; // Consume modifier character.
1531 if (*LastEmitted != '}') {
1532 llvm_report_error("Bad ${} expression in inline asm string: '"
1533 + std::string(AsmStr) + "'");
1535 ++LastEmitted; // Consume '}' character.
1538 if ((unsigned)Val >= NumOperands-1) {
1539 llvm_report_error("Invalid $ operand number in inline asm string: '"
1540 + std::string(AsmStr) + "'");
1543 // Okay, we finally have a value number. Ask the target to print this
1545 if (CurVariant == -1 || CurVariant == AsmPrinterVariant) {
1550 // Scan to find the machine operand number for the operand.
1551 for (; Val; --Val) {
1552 if (OpNo >= MI->getNumOperands()) break;
1553 unsigned OpFlags = MI->getOperand(OpNo).getImm();
1554 OpNo += InlineAsm::getNumOperandRegisters(OpFlags) + 1;
1557 if (OpNo >= MI->getNumOperands()) {
1560 unsigned OpFlags = MI->getOperand(OpNo).getImm();
1561 ++OpNo; // Skip over the ID number.
1563 if (Modifier[0] == 'l') // labels are target independent
1564 OS << *MI->getOperand(OpNo).getMBB()->getSymbol();
1566 AsmPrinter *AP = const_cast<AsmPrinter*>(this);
1567 if ((OpFlags & 7) == 4) {
1568 Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant,
1569 Modifier[0] ? Modifier : 0);
1571 Error = AP->PrintAsmOperand(MI, OpNo, AsmPrinterVariant,
1572 Modifier[0] ? Modifier : 0);
1578 raw_string_ostream Msg(msg);
1579 Msg << "Invalid operand found in inline asm: '" << AsmStr << "'\n";
1581 llvm_report_error(Msg.str());
1591 EmitInlineAsm(OS.str());
1594 // Emit the #NOAPP end marker. This has to happen even if verbose-asm isn't
1595 // enabled, so we use EmitRawText.
1596 if (OutStreamer.hasRawTextSupport())
1597 OutStreamer.EmitRawText(Twine("\t")+MAI->getCommentString()+
1598 MAI->getInlineAsmEnd());
1601 /// printImplicitDef - This method prints the specified machine instruction
1602 /// that is an implicit def.
1603 void AsmPrinter::printImplicitDef(const MachineInstr *MI) const {
1604 if (!VerboseAsm) return;
1605 OutStreamer.AddComment(Twine("implicit-def: ") +
1606 TRI->getName(MI->getOperand(0).getReg()));
1607 OutStreamer.AddBlankLine();
1610 void AsmPrinter::printKill(const MachineInstr *MI) const {
1611 if (!VerboseAsm) return;
1612 O.PadToColumn(MAI->getCommentColumn());
1614 std::string Str = "kill:";
1615 for (unsigned n = 0, e = MI->getNumOperands(); n != e; ++n) {
1616 const MachineOperand &Op = MI->getOperand(n);
1617 assert(Op.isReg() && "KILL instruction must have only register operands");
1619 Str += TRI->getName(Op.getReg());
1620 Str += (Op.isDef() ? "<def>" : "<kill>");
1622 OutStreamer.AddComment(Str);
1623 OutStreamer.AddBlankLine();
1626 /// printLabel - This method prints a local label used by debug and
1627 /// exception handling tables.
1628 void AsmPrinter::printLabelInst(const MachineInstr *MI) const {
1629 OutStreamer.EmitLabel(MI->getOperand(0).getMCSymbol());
1632 /// PrintAsmOperand - Print the specified operand of MI, an INLINEASM
1633 /// instruction, using the specified assembler variant. Targets should
1634 /// override this to format as appropriate.
1635 bool AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
1636 unsigned AsmVariant, const char *ExtraCode) {
1637 // Target doesn't support this yet!
1641 bool AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
1642 unsigned AsmVariant,
1643 const char *ExtraCode) {
1644 // Target doesn't support this yet!
1648 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
1649 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
1652 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
1653 return MMI->getAddrLabelSymbol(BB);
1656 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1657 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1658 return OutContext.GetOrCreateSymbol
1659 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
1660 + "_" + Twine(CPID));
1663 /// GetJTISymbol - Return the symbol for the specified jump table entry.
1664 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1665 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
1668 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
1669 /// FIXME: privatize to AsmPrinter.
1670 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
1671 return OutContext.GetOrCreateSymbol
1672 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
1673 Twine(UID) + "_set_" + Twine(MBBID));
1676 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1677 /// global value name as its base, with the specified suffix, and where the
1678 /// symbol is forced to have private linkage if ForcePrivate is true.
1679 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1681 bool ForcePrivate) const {
1682 SmallString<60> NameStr;
1683 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1684 NameStr.append(Suffix.begin(), Suffix.end());
1685 return OutContext.GetOrCreateSymbol(NameStr.str());
1688 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
1690 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
1691 SmallString<60> NameStr;
1692 Mang->getNameWithPrefix(NameStr, Sym);
1693 return OutContext.GetOrCreateSymbol(NameStr.str());
1698 /// PrintParentLoopComment - Print comments about parent loops of this one.
1699 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1700 unsigned FunctionNumber) {
1701 if (Loop == 0) return;
1702 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
1703 OS.indent(Loop->getLoopDepth()*2)
1704 << "Parent Loop BB" << FunctionNumber << "_"
1705 << Loop->getHeader()->getNumber()
1706 << " Depth=" << Loop->getLoopDepth() << '\n';
1710 /// PrintChildLoopComment - Print comments about child loops within
1711 /// the loop for this basic block, with nesting.
1712 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1713 unsigned FunctionNumber) {
1714 // Add child loop information
1715 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
1716 OS.indent((*CL)->getLoopDepth()*2)
1717 << "Child Loop BB" << FunctionNumber << "_"
1718 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
1720 PrintChildLoopComment(OS, *CL, FunctionNumber);
1724 /// PrintBasicBlockLoopComments - Pretty-print comments for basic blocks.
1725 static void PrintBasicBlockLoopComments(const MachineBasicBlock &MBB,
1726 const MachineLoopInfo *LI,
1727 const AsmPrinter &AP) {
1728 // Add loop depth information
1729 const MachineLoop *Loop = LI->getLoopFor(&MBB);
1730 if (Loop == 0) return;
1732 MachineBasicBlock *Header = Loop->getHeader();
1733 assert(Header && "No header for loop");
1735 // If this block is not a loop header, just print out what is the loop header
1737 if (Header != &MBB) {
1738 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
1739 Twine(AP.getFunctionNumber())+"_" +
1740 Twine(Loop->getHeader()->getNumber())+
1741 " Depth="+Twine(Loop->getLoopDepth()));
1745 // Otherwise, it is a loop header. Print out information about child and
1747 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
1749 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
1752 OS.indent(Loop->getLoopDepth()*2-2);
1757 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
1759 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
1763 /// EmitBasicBlockStart - This method prints the label for the specified
1764 /// MachineBasicBlock, an alignment (if present) and a comment describing
1765 /// it if appropriate.
1766 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
1767 // Emit an alignment directive for this block, if needed.
1768 if (unsigned Align = MBB->getAlignment())
1769 EmitAlignment(Log2_32(Align));
1771 // If the block has its address taken, emit any labels that were used to
1772 // reference the block. It is possible that there is more than one label
1773 // here, because multiple LLVM BB's may have been RAUW'd to this block after
1774 // the references were generated.
1775 if (MBB->hasAddressTaken()) {
1776 const BasicBlock *BB = MBB->getBasicBlock();
1778 OutStreamer.AddComment("Block address taken");
1780 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
1782 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
1783 OutStreamer.EmitLabel(Syms[i]);
1786 // Print the main label for the block.
1787 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
1788 if (VerboseAsm && OutStreamer.hasRawTextSupport()) {
1789 if (const BasicBlock *BB = MBB->getBasicBlock())
1791 OutStreamer.AddComment("%" + BB->getName());
1793 PrintBasicBlockLoopComments(*MBB, LI, *this);
1795 // NOTE: Want this comment at start of line, don't emit with AddComment.
1796 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" +
1797 Twine(MBB->getNumber()) + ":");
1801 if (const BasicBlock *BB = MBB->getBasicBlock())
1803 OutStreamer.AddComment("%" + BB->getName());
1804 PrintBasicBlockLoopComments(*MBB, LI, *this);
1807 OutStreamer.EmitLabel(MBB->getSymbol());
1811 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility) const {
1812 MCSymbolAttr Attr = MCSA_Invalid;
1814 switch (Visibility) {
1816 case GlobalValue::HiddenVisibility:
1817 Attr = MAI->getHiddenVisibilityAttr();
1819 case GlobalValue::ProtectedVisibility:
1820 Attr = MAI->getProtectedVisibilityAttr();
1824 if (Attr != MCSA_Invalid)
1825 OutStreamer.EmitSymbolAttribute(Sym, Attr);
1828 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1830 OS << '+' << Offset;
1831 else if (Offset < 0)
1835 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
1836 /// exactly one predecessor and the control transfer mechanism between
1837 /// the predecessor and this block is a fall-through.
1838 bool AsmPrinter::isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB)
1840 // If this is a landing pad, it isn't a fall through. If it has no preds,
1841 // then nothing falls through to it.
1842 if (MBB->isLandingPad() || MBB->pred_empty())
1845 // If there isn't exactly one predecessor, it can't be a fall through.
1846 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
1848 if (PI2 != MBB->pred_end())
1851 // The predecessor has to be immediately before this block.
1852 const MachineBasicBlock *Pred = *PI;
1854 if (!Pred->isLayoutSuccessor(MBB))
1857 // If the block is completely empty, then it definitely does fall through.
1861 // Otherwise, check the last instruction.
1862 const MachineInstr &LastInst = Pred->back();
1863 return !LastInst.getDesc().isBarrier();
1868 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1869 if (!S->usesMetadata())
1872 gcp_iterator GCPI = GCMetadataPrinters.find(S);
1873 if (GCPI != GCMetadataPrinters.end())
1874 return GCPI->second;
1876 const char *Name = S->getName().c_str();
1878 for (GCMetadataPrinterRegistry::iterator
1879 I = GCMetadataPrinterRegistry::begin(),
1880 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1881 if (strcmp(Name, I->getName()) == 0) {
1882 GCMetadataPrinter *GMP = I->instantiate();
1884 GCMetadataPrinters.insert(std::make_pair(S, GMP));
1888 llvm_report_error("no GCMetadataPrinter registered for GC: " + Twine(Name));