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"
54 STATISTIC(EmittedInsts, "Number of machine instrs printed");
56 char AsmPrinter::ID = 0;
58 typedef DenseMap<GCStrategy*,GCMetadataPrinter*> gcp_map_type;
59 static gcp_map_type &getGCMap(void *&P) {
61 P = new gcp_map_type();
62 return *(gcp_map_type*)P;
66 AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
67 : MachineFunctionPass(&ID),
68 TM(tm), MAI(tm.getMCAsmInfo()),
69 OutContext(Streamer.getContext()),
70 OutStreamer(Streamer),
71 LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {
73 GCMetadataPrinters = 0;
74 VerboseAsm = Streamer.isVerboseAsm();
77 AsmPrinter::~AsmPrinter() {
78 if (GCMetadataPrinters != 0) {
79 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
81 for (gcp_map_type::iterator I = GCMap.begin(), E = GCMap.end(); I != E; ++I)
84 GCMetadataPrinters = 0;
90 /// getFunctionNumber - Return a unique ID for the current function.
92 unsigned AsmPrinter::getFunctionNumber() const {
93 return MF->getFunctionNumber();
96 TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
97 return TM.getTargetLowering()->getObjFileLowering();
100 /// getCurrentSection() - Return the current section we are emitting to.
101 const MCSection *AsmPrinter::getCurrentSection() const {
102 return OutStreamer.getCurrentSection();
106 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
107 AU.setPreservesAll();
108 MachineFunctionPass::getAnalysisUsage(AU);
109 AU.addRequired<MachineModuleInfo>();
110 AU.addRequired<GCModuleInfo>();
112 AU.addRequired<MachineLoopInfo>();
115 bool AsmPrinter::doInitialization(Module &M) {
116 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
117 MMI->AnalyzeModule(M);
119 // Initialize TargetLoweringObjectFile.
120 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
121 .Initialize(OutContext, TM);
123 Mang = new Mangler(OutContext, *TM.getTargetData());
125 // Allow the target to emit any magic that it wants at the start of the file.
126 EmitStartOfAsmFile(M);
128 // Very minimal debug info. It is ignored if we emit actual debug info. If we
129 // don't, this at least helps the user find where a global came from.
130 if (MAI->hasSingleParameterDotFile()) {
132 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
135 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
136 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
137 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
138 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
139 MP->beginAssembly(*this);
141 // Emit module-level inline asm if it exists.
142 if (!M.getModuleInlineAsm().empty()) {
143 OutStreamer.AddComment("Start of file scope inline assembly");
144 OutStreamer.AddBlankLine();
145 EmitInlineAsm(M.getModuleInlineAsm());
146 OutStreamer.AddComment("End of file scope inline assembly");
147 OutStreamer.AddBlankLine();
150 DW = getAnalysisIfAvailable<DwarfWriter>();
152 DW->BeginModule(&M, this);
157 void AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const {
158 switch ((GlobalValue::LinkageTypes)Linkage) {
159 case GlobalValue::CommonLinkage:
160 case GlobalValue::LinkOnceAnyLinkage:
161 case GlobalValue::LinkOnceODRLinkage:
162 case GlobalValue::WeakAnyLinkage:
163 case GlobalValue::WeakODRLinkage:
164 case GlobalValue::LinkerPrivateLinkage:
165 if (MAI->getWeakDefDirective() != 0) {
167 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
168 // .weak_definition _foo
169 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
170 } else if (const char *LinkOnce = MAI->getLinkOnceDirective()) {
172 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
173 // FIXME: linkonce should be a section attribute, handled by COFF Section
175 // http://sourceware.org/binutils/docs-2.20/as/Linkonce.html#Linkonce
177 // FIXME: It would be nice to use .linkonce samesize for non-common
179 OutStreamer.EmitRawText(StringRef(LinkOnce));
182 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
185 case GlobalValue::DLLExportLinkage:
186 case GlobalValue::AppendingLinkage:
187 // FIXME: appending linkage variables should go into a section of
188 // their name or something. For now, just emit them as external.
189 case GlobalValue::ExternalLinkage:
190 // If external or appending, declare as a global symbol.
192 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
194 case GlobalValue::PrivateLinkage:
195 case GlobalValue::InternalLinkage:
198 llvm_unreachable("Unknown linkage type!");
203 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
204 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
205 if (!GV->hasInitializer()) // External globals require no code.
208 // Check to see if this is a special global used by LLVM, if so, emit it.
209 if (EmitSpecialLLVMGlobal(GV))
212 MCSymbol *GVSym = Mang->getSymbol(GV);
213 EmitVisibility(GVSym, GV->getVisibility());
215 if (MAI->hasDotTypeDotSizeDirective())
216 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
218 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
220 const TargetData *TD = TM.getTargetData();
221 unsigned Size = TD->getTypeAllocSize(GV->getType()->getElementType());
222 unsigned AlignLog = TD->getPreferredAlignmentLog(GV);
224 // Handle common and BSS local symbols (.lcomm).
225 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
226 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
229 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
230 /*PrintType=*/false, GV->getParent());
231 OutStreamer.GetCommentOS() << '\n';
234 // Handle common symbols.
235 if (GVKind.isCommon()) {
237 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
241 // Handle local BSS symbols.
242 if (MAI->hasMachoZeroFillDirective()) {
243 const MCSection *TheSection =
244 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
245 // .zerofill __DATA, __bss, _foo, 400, 5
246 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
250 if (MAI->hasLCOMMDirective()) {
252 OutStreamer.EmitLocalCommonSymbol(GVSym, Size);
257 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
259 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
263 const MCSection *TheSection =
264 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
266 // Handle the zerofill directive on darwin, which is a special form of BSS
268 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
270 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
271 // .zerofill __DATA, __common, _foo, 400, 5
272 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
276 OutStreamer.SwitchSection(TheSection);
278 EmitLinkage(GV->getLinkage(), GVSym);
279 EmitAlignment(AlignLog, GV);
282 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
283 /*PrintType=*/false, GV->getParent());
284 OutStreamer.GetCommentOS() << '\n';
286 OutStreamer.EmitLabel(GVSym);
288 EmitGlobalConstant(GV->getInitializer());
290 if (MAI->hasDotTypeDotSizeDirective())
292 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
294 OutStreamer.AddBlankLine();
297 /// EmitFunctionHeader - This method emits the header for the current
299 void AsmPrinter::EmitFunctionHeader() {
300 // Print out constants referenced by the function
303 // Print the 'header' of function.
304 const Function *F = MF->getFunction();
306 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
307 EmitVisibility(CurrentFnSym, F->getVisibility());
309 EmitLinkage(F->getLinkage(), CurrentFnSym);
310 EmitAlignment(MF->getAlignment(), F);
312 if (MAI->hasDotTypeDotSizeDirective())
313 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
316 WriteAsOperand(OutStreamer.GetCommentOS(), F,
317 /*PrintType=*/false, F->getParent());
318 OutStreamer.GetCommentOS() << '\n';
321 // Emit the CurrentFnSym. This is a virtual function to allow targets to
322 // do their wild and crazy things as required.
323 EmitFunctionEntryLabel();
325 // If the function had address-taken blocks that got deleted, then we have
326 // references to the dangling symbols. Emit them at the start of the function
327 // so that we don't get references to undefined symbols.
328 std::vector<MCSymbol*> DeadBlockSyms;
329 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
330 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
331 OutStreamer.AddComment("Address taken block that was later removed");
332 OutStreamer.EmitLabel(DeadBlockSyms[i]);
335 // Add some workaround for linkonce linkage on Cygwin\MinGW.
336 if (MAI->getLinkOnceDirective() != 0 &&
337 (F->hasLinkOnceLinkage() || F->hasWeakLinkage())) {
338 // FIXME: What is this?
340 OutContext.GetOrCreateSymbol(Twine("Lllvm$workaround$fake$stub$")+
341 CurrentFnSym->getName());
342 OutStreamer.EmitLabel(FakeStub);
345 // Emit pre-function debug and/or EH information.
346 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
347 DW->BeginFunction(MF);
350 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
351 /// function. This can be overridden by targets as required to do custom stuff.
352 void AsmPrinter::EmitFunctionEntryLabel() {
353 OutStreamer.EmitLabel(CurrentFnSym);
357 /// EmitComments - Pretty-print comments for instructions.
358 static void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
359 const MachineFunction *MF = MI.getParent()->getParent();
360 const TargetMachine &TM = MF->getTarget();
362 DebugLoc DL = MI.getDebugLoc();
363 if (!DL.isUnknown()) { // Print source line info.
364 DIScope Scope(DL.getScope(MF->getFunction()->getContext()));
365 // Omit the directory, because it's likely to be long and uninteresting.
367 CommentOS << Scope.getFilename();
369 CommentOS << "<unknown>";
370 CommentOS << ':' << DL.getLine();
371 if (DL.getCol() != 0)
372 CommentOS << ':' << DL.getCol();
376 // Check for spills and reloads
379 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
381 // We assume a single instruction only has a spill or reload, not
383 const MachineMemOperand *MMO;
384 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
385 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
386 MMO = *MI.memoperands_begin();
387 CommentOS << MMO->getSize() << "-byte Reload\n";
389 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
390 if (FrameInfo->isSpillSlotObjectIndex(FI))
391 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
392 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
393 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
394 MMO = *MI.memoperands_begin();
395 CommentOS << MMO->getSize() << "-byte Spill\n";
397 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
398 if (FrameInfo->isSpillSlotObjectIndex(FI))
399 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
402 // Check for spill-induced copies
403 unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
404 if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg,
405 SrcSubIdx, DstSubIdx)) {
406 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
407 CommentOS << " Reload Reuse\n";
413 /// EmitFunctionBody - This method emits the body and trailer for a
415 void AsmPrinter::EmitFunctionBody() {
416 // Emit target-specific gunk before the function body.
417 EmitFunctionBodyStart();
419 bool ShouldPrintDebugScopes =
420 DW && MAI->doesSupportDebugInformation() &&DW->ShouldEmitDwarfDebug();
422 // Print out code for the function.
423 bool HasAnyRealCode = false;
424 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
426 // Print a label for the basic block.
427 EmitBasicBlockStart(I);
428 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
430 // Print the assembly for the instruction.
432 HasAnyRealCode = true;
436 if (ShouldPrintDebugScopes)
440 EmitComments(*II, OutStreamer.GetCommentOS());
442 switch (II->getOpcode()) {
443 case TargetOpcode::DBG_LABEL:
444 case TargetOpcode::EH_LABEL:
445 case TargetOpcode::GC_LABEL:
446 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol());
448 case TargetOpcode::INLINEASM:
451 case TargetOpcode::IMPLICIT_DEF:
454 case TargetOpcode::KILL:
462 if (ShouldPrintDebugScopes)
467 // If the function is empty and the object file uses .subsections_via_symbols,
468 // then we need to emit *something* to the function body to prevent the
469 // labels from collapsing together. Just emit a 0 byte.
470 if (MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)
471 OutStreamer.EmitIntValue(0, 1, 0/*addrspace*/);
473 // Emit target-specific gunk after the function body.
474 EmitFunctionBodyEnd();
476 // If the target wants a .size directive for the size of the function, emit
478 if (MAI->hasDotTypeDotSizeDirective()) {
479 // Create a symbol for the end of function, so we can get the size as
480 // difference between the function label and the temp label.
481 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
482 OutStreamer.EmitLabel(FnEndLabel);
484 const MCExpr *SizeExp =
485 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
486 MCSymbolRefExpr::Create(CurrentFnSym, OutContext),
488 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
491 // Emit post-function debug information.
492 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
495 // Print out jump tables referenced by the function.
498 OutStreamer.AddBlankLine();
502 bool AsmPrinter::doFinalization(Module &M) {
503 // Emit global variables.
504 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
506 EmitGlobalVariable(I);
508 // Emit final debug information.
509 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
512 // If the target wants to know about weak references, print them all.
513 if (MAI->getWeakRefDirective()) {
514 // FIXME: This is not lazy, it would be nice to only print weak references
515 // to stuff that is actually used. Note that doing so would require targets
516 // to notice uses in operands (due to constant exprs etc). This should
517 // happen with the MC stuff eventually.
519 // Print out module-level global variables here.
520 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
522 if (!I->hasExternalWeakLinkage()) continue;
523 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
526 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
527 if (!I->hasExternalWeakLinkage()) continue;
528 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
532 if (MAI->hasSetDirective()) {
533 OutStreamer.AddBlankLine();
534 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
536 MCSymbol *Name = Mang->getSymbol(I);
538 const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
539 MCSymbol *Target = Mang->getSymbol(GV);
541 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
542 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
543 else if (I->hasWeakLinkage())
544 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
546 assert(I->hasLocalLinkage() && "Invalid alias linkage");
548 EmitVisibility(Name, I->getVisibility());
550 // Emit the directives as assignments aka .set:
551 OutStreamer.EmitAssignment(Name,
552 MCSymbolRefExpr::Create(Target, OutContext));
556 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
557 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
558 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
559 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
560 MP->finishAssembly(*this);
562 // If we don't have any trampolines, then we don't require stack memory
563 // to be executable. Some targets have a directive to declare this.
564 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
565 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
566 if (MCSection *S = MAI->getNonexecutableStackSection(OutContext))
567 OutStreamer.SwitchSection(S);
569 // Allow the target to emit any magic that it wants at the end of the file,
570 // after everything else has gone out.
573 delete Mang; Mang = 0;
576 OutStreamer.Finish();
580 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
582 // Get the function symbol.
583 CurrentFnSym = Mang->getSymbol(MF.getFunction());
586 LI = &getAnalysis<MachineLoopInfo>();
590 // SectionCPs - Keep track the alignment, constpool entries per Section.
594 SmallVector<unsigned, 4> CPEs;
595 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
599 /// EmitConstantPool - Print to the current output stream assembly
600 /// representations of the constants in the constant pool MCP. This is
601 /// used to print out constants which have been "spilled to memory" by
602 /// the code generator.
604 void AsmPrinter::EmitConstantPool() {
605 const MachineConstantPool *MCP = MF->getConstantPool();
606 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
607 if (CP.empty()) return;
609 // Calculate sections for constant pool entries. We collect entries to go into
610 // the same section together to reduce amount of section switch statements.
611 SmallVector<SectionCPs, 4> CPSections;
612 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
613 const MachineConstantPoolEntry &CPE = CP[i];
614 unsigned Align = CPE.getAlignment();
617 switch (CPE.getRelocationInfo()) {
618 default: llvm_unreachable("Unknown section kind");
619 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
621 Kind = SectionKind::getReadOnlyWithRelLocal();
624 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
625 case 4: Kind = SectionKind::getMergeableConst4(); break;
626 case 8: Kind = SectionKind::getMergeableConst8(); break;
627 case 16: Kind = SectionKind::getMergeableConst16();break;
628 default: Kind = SectionKind::getMergeableConst(); break;
632 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
634 // The number of sections are small, just do a linear search from the
635 // last section to the first.
637 unsigned SecIdx = CPSections.size();
638 while (SecIdx != 0) {
639 if (CPSections[--SecIdx].S == S) {
645 SecIdx = CPSections.size();
646 CPSections.push_back(SectionCPs(S, Align));
649 if (Align > CPSections[SecIdx].Alignment)
650 CPSections[SecIdx].Alignment = Align;
651 CPSections[SecIdx].CPEs.push_back(i);
654 // Now print stuff into the calculated sections.
655 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
656 OutStreamer.SwitchSection(CPSections[i].S);
657 EmitAlignment(Log2_32(CPSections[i].Alignment));
660 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
661 unsigned CPI = CPSections[i].CPEs[j];
662 MachineConstantPoolEntry CPE = CP[CPI];
664 // Emit inter-object padding for alignment.
665 unsigned AlignMask = CPE.getAlignment() - 1;
666 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
667 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/);
669 const Type *Ty = CPE.getType();
670 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
672 // Emit the label with a comment on it.
674 OutStreamer.GetCommentOS() << "constant pool ";
675 WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(),
676 MF->getFunction()->getParent());
677 OutStreamer.GetCommentOS() << '\n';
679 OutStreamer.EmitLabel(GetCPISymbol(CPI));
681 if (CPE.isMachineConstantPoolEntry())
682 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
684 EmitGlobalConstant(CPE.Val.ConstVal);
689 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
690 /// by the current function to the current output stream.
692 void AsmPrinter::EmitJumpTableInfo() {
693 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
694 if (MJTI == 0) return;
695 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
696 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
697 if (JT.empty()) return;
699 // Pick the directive to use to print the jump table entries, and switch to
700 // the appropriate section.
701 const Function *F = MF->getFunction();
702 bool JTInDiffSection = false;
703 if (// In PIC mode, we need to emit the jump table to the same section as the
704 // function body itself, otherwise the label differences won't make sense.
705 // FIXME: Need a better predicate for this: what about custom entries?
706 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
707 // We should also do if the section name is NULL or function is declared
708 // in discardable section
709 // FIXME: this isn't the right predicate, should be based on the MCSection
711 F->isWeakForLinker()) {
712 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
714 // Otherwise, drop it in the readonly section.
715 const MCSection *ReadOnlySection =
716 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
717 OutStreamer.SwitchSection(ReadOnlySection);
718 JTInDiffSection = true;
721 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData())));
723 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
724 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
726 // If this jump table was deleted, ignore it.
727 if (JTBBs.empty()) continue;
729 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
730 // .set directive for each unique entry. This reduces the number of
731 // relocations the assembler will generate for the jump table.
732 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
733 MAI->hasSetDirective()) {
734 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
735 const TargetLowering *TLI = TM.getTargetLowering();
736 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
737 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
738 const MachineBasicBlock *MBB = JTBBs[ii];
739 if (!EmittedSets.insert(MBB)) continue;
741 // .set LJTSet, LBB32-base
743 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
744 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
745 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
749 // On some targets (e.g. Darwin) we want to emit two consequtive labels
750 // before each jump table. The first label is never referenced, but tells
751 // the assembler and linker the extents of the jump table object. The
752 // second label is actually referenced by the code.
753 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
754 // FIXME: This doesn't have to have any specific name, just any randomly
755 // named and numbered 'l' label would work. Simplify GetJTISymbol.
756 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
758 OutStreamer.EmitLabel(GetJTISymbol(JTI));
760 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
761 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
765 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
767 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
768 const MachineBasicBlock *MBB,
769 unsigned UID) const {
770 const MCExpr *Value = 0;
771 switch (MJTI->getEntryKind()) {
772 case MachineJumpTableInfo::EK_Inline:
773 llvm_unreachable("Cannot emit EK_Inline jump table entry"); break;
774 case MachineJumpTableInfo::EK_Custom32:
775 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
778 case MachineJumpTableInfo::EK_BlockAddress:
779 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
781 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
783 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
784 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
785 // with a relocation as gp-relative, e.g.:
787 MCSymbol *MBBSym = MBB->getSymbol();
788 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
792 case MachineJumpTableInfo::EK_LabelDifference32: {
793 // EK_LabelDifference32 - Each entry is the address of the block minus
794 // the address of the jump table. This is used for PIC jump tables where
795 // gprel32 is not supported. e.g.:
796 // .word LBB123 - LJTI1_2
797 // If the .set directive is supported, this is emitted as:
798 // .set L4_5_set_123, LBB123 - LJTI1_2
799 // .word L4_5_set_123
801 // If we have emitted set directives for the jump table entries, print
802 // them rather than the entries themselves. If we're emitting PIC, then
803 // emit the table entries as differences between two text section labels.
804 if (MAI->hasSetDirective()) {
805 // If we used .set, reference the .set's symbol.
806 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
810 // Otherwise, use the difference as the jump table entry.
811 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
812 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
813 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
818 assert(Value && "Unknown entry kind!");
820 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData());
821 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0);
825 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
826 /// special global used by LLVM. If so, emit it and return true, otherwise
827 /// do nothing and return false.
828 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
829 if (GV->getName() == "llvm.used") {
830 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
831 EmitLLVMUsedList(GV->getInitializer());
835 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
836 if (GV->getSection() == "llvm.metadata" ||
837 GV->hasAvailableExternallyLinkage())
840 if (!GV->hasAppendingLinkage()) return false;
842 assert(GV->hasInitializer() && "Not a special LLVM global!");
844 const TargetData *TD = TM.getTargetData();
845 unsigned Align = Log2_32(TD->getPointerPrefAlignment());
846 if (GV->getName() == "llvm.global_ctors") {
847 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection());
848 EmitAlignment(Align, 0);
849 EmitXXStructorList(GV->getInitializer());
851 if (TM.getRelocationModel() == Reloc::Static &&
852 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
853 StringRef Sym(".constructors_used");
854 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
860 if (GV->getName() == "llvm.global_dtors") {
861 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection());
862 EmitAlignment(Align, 0);
863 EmitXXStructorList(GV->getInitializer());
865 if (TM.getRelocationModel() == Reloc::Static &&
866 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
867 StringRef Sym(".destructors_used");
868 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
877 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
878 /// global in the specified llvm.used list for which emitUsedDirectiveFor
879 /// is true, as being used with this directive.
880 void AsmPrinter::EmitLLVMUsedList(Constant *List) {
881 // Should be an array of 'i8*'.
882 ConstantArray *InitList = dyn_cast<ConstantArray>(List);
883 if (InitList == 0) return;
885 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
886 const GlobalValue *GV =
887 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
888 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
889 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip);
893 /// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the
894 /// function pointers, ignoring the init priority.
895 void AsmPrinter::EmitXXStructorList(Constant *List) {
896 // Should be an array of '{ int, void ()* }' structs. The first value is the
897 // init priority, which we ignore.
898 if (!isa<ConstantArray>(List)) return;
899 ConstantArray *InitList = cast<ConstantArray>(List);
900 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
901 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
902 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs.
904 if (CS->getOperand(1)->isNullValue())
905 return; // Found a null terminator, exit printing.
906 // Emit the function pointer.
907 EmitGlobalConstant(CS->getOperand(1));
911 /// EmitInlineAsm - Emit a blob of inline asm to the output streamer.
912 void AsmPrinter::EmitInlineAsm(StringRef Str) const {
913 assert(!Str.empty() && "Can't emit empty inline asm block");
915 // If the output streamer is actually a .s file, just emit the blob textually.
916 // This is useful in case the asm parser doesn't handle something but the
917 // system assembler does.
918 if (OutStreamer.hasRawTextSupport()) {
919 OutStreamer.EmitRawText(Str);
923 errs() << "Inline asm not supported by this streamer!\n";
927 //===--------------------------------------------------------------------===//
928 // Emission and print routines
931 /// EmitInt8 - Emit a byte directive and value.
933 void AsmPrinter::EmitInt8(int Value) const {
934 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/);
937 /// EmitInt16 - Emit a short directive and value.
939 void AsmPrinter::EmitInt16(int Value) const {
940 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/);
943 /// EmitInt32 - Emit a long directive and value.
945 void AsmPrinter::EmitInt32(int Value) const {
946 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/);
949 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
950 /// in bytes of the directive is specified by Size and Hi/Lo specify the
951 /// labels. This implicitly uses .set if it is available.
952 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
953 unsigned Size) const {
954 // Get the Hi-Lo expression.
956 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
957 MCSymbolRefExpr::Create(Lo, OutContext),
960 if (!MAI->hasSetDirective()) {
961 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/);
965 // Otherwise, emit with .set (aka assignment).
967 OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) +
968 "set" + Twine(SetCounter++));
969 OutStreamer.EmitAssignment(SetLabel, Diff);
970 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/);
974 //===----------------------------------------------------------------------===//
976 // EmitAlignment - Emit an alignment directive to the specified power of
977 // two boundary. For example, if you pass in 3 here, you will get an 8
978 // byte alignment. If a global value is specified, and if that global has
979 // an explicit alignment requested, it will unconditionally override the
980 // alignment request. However, if ForcedAlignBits is specified, this value
981 // has final say: the ultimate alignment will be the max of ForcedAlignBits
982 // and the alignment computed with NumBits and the global.
986 // if (GV && GV->hasalignment) Align = GV->getalignment();
987 // Align = std::max(Align, ForcedAlignBits);
989 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
990 unsigned ForcedAlignBits,
991 bool UseFillExpr) const {
992 if (GV && GV->getAlignment())
993 NumBits = Log2_32(GV->getAlignment());
994 NumBits = std::max(NumBits, ForcedAlignBits);
996 if (NumBits == 0) return; // No need to emit alignment.
998 if (getCurrentSection()->getKind().isText())
999 OutStreamer.EmitCodeAlignment(1 << NumBits);
1001 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
1004 /// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
1006 static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) {
1007 MCContext &Ctx = AP.OutContext;
1009 if (CV->isNullValue() || isa<UndefValue>(CV))
1010 return MCConstantExpr::Create(0, Ctx);
1012 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1013 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1015 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1016 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx);
1017 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1018 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1020 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1022 llvm_unreachable("Unknown constant value to lower!");
1023 return MCConstantExpr::Create(0, Ctx);
1026 switch (CE->getOpcode()) {
1028 // If the code isn't optimized, there may be outstanding folding
1029 // opportunities. Attempt to fold the expression using TargetData as a
1030 // last resort before giving up.
1032 ConstantFoldConstantExpression(CE, AP.TM.getTargetData()))
1034 return LowerConstant(C, AP);
1038 llvm_unreachable("FIXME: Don't support this constant expr");
1039 case Instruction::GetElementPtr: {
1040 const TargetData &TD = *AP.TM.getTargetData();
1041 // Generate a symbolic expression for the byte address
1042 const Constant *PtrVal = CE->getOperand(0);
1043 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
1044 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0],
1047 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
1051 // Truncate/sext the offset to the pointer size.
1052 if (TD.getPointerSizeInBits() != 64) {
1053 int SExtAmount = 64-TD.getPointerSizeInBits();
1054 Offset = (Offset << SExtAmount) >> SExtAmount;
1057 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1061 case Instruction::Trunc:
1062 // We emit the value and depend on the assembler to truncate the generated
1063 // expression properly. This is important for differences between
1064 // blockaddress labels. Since the two labels are in the same function, it
1065 // is reasonable to treat their delta as a 32-bit value.
1067 case Instruction::BitCast:
1068 return LowerConstant(CE->getOperand(0), AP);
1070 case Instruction::IntToPtr: {
1071 const TargetData &TD = *AP.TM.getTargetData();
1072 // Handle casts to pointers by changing them into casts to the appropriate
1073 // integer type. This promotes constant folding and simplifies this code.
1074 Constant *Op = CE->getOperand(0);
1075 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
1077 return LowerConstant(Op, AP);
1080 case Instruction::PtrToInt: {
1081 const TargetData &TD = *AP.TM.getTargetData();
1082 // Support only foldable casts to/from pointers that can be eliminated by
1083 // changing the pointer to the appropriately sized integer type.
1084 Constant *Op = CE->getOperand(0);
1085 const Type *Ty = CE->getType();
1087 const MCExpr *OpExpr = LowerConstant(Op, AP);
1089 // We can emit the pointer value into this slot if the slot is an
1090 // integer slot equal to the size of the pointer.
1091 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
1094 // Otherwise the pointer is smaller than the resultant integer, mask off
1095 // the high bits so we are sure to get a proper truncation if the input is
1097 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
1098 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1099 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1102 // The MC library also has a right-shift operator, but it isn't consistently
1103 // signed or unsigned between different targets.
1104 case Instruction::Add:
1105 case Instruction::Sub:
1106 case Instruction::Mul:
1107 case Instruction::SDiv:
1108 case Instruction::SRem:
1109 case Instruction::Shl:
1110 case Instruction::And:
1111 case Instruction::Or:
1112 case Instruction::Xor: {
1113 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP);
1114 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP);
1115 switch (CE->getOpcode()) {
1116 default: llvm_unreachable("Unknown binary operator constant cast expr");
1117 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1118 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1119 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1120 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1121 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1122 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1123 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1124 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1125 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1131 static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
1133 if (AddrSpace != 0 || !CA->isString()) {
1134 // Not a string. Print the values in successive locations
1135 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1136 AP.EmitGlobalConstant(CA->getOperand(i), AddrSpace);
1140 // Otherwise, it can be emitted as .ascii.
1141 SmallVector<char, 128> TmpVec;
1142 TmpVec.reserve(CA->getNumOperands());
1143 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1144 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
1146 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace);
1149 static void EmitGlobalConstantVector(const ConstantVector *CV,
1150 unsigned AddrSpace, AsmPrinter &AP) {
1151 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1152 AP.EmitGlobalConstant(CV->getOperand(i), AddrSpace);
1155 static void EmitGlobalConstantStruct(const ConstantStruct *CS,
1156 unsigned AddrSpace, AsmPrinter &AP) {
1157 // Print the fields in successive locations. Pad to align if needed!
1158 const TargetData *TD = AP.TM.getTargetData();
1159 unsigned Size = TD->getTypeAllocSize(CS->getType());
1160 const StructLayout *Layout = TD->getStructLayout(CS->getType());
1161 uint64_t SizeSoFar = 0;
1162 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1163 const Constant *Field = CS->getOperand(i);
1165 // Check if padding is needed and insert one or more 0s.
1166 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
1167 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1168 - Layout->getElementOffset(i)) - FieldSize;
1169 SizeSoFar += FieldSize + PadSize;
1171 // Now print the actual field value.
1172 AP.EmitGlobalConstant(Field, AddrSpace);
1174 // Insert padding - this may include padding to increase the size of the
1175 // current field up to the ABI size (if the struct is not packed) as well
1176 // as padding to ensure that the next field starts at the right offset.
1177 AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
1179 assert(SizeSoFar == Layout->getSizeInBytes() &&
1180 "Layout of constant struct may be incorrect!");
1183 static void EmitGlobalConstantUnion(const ConstantUnion *CU,
1184 unsigned AddrSpace, AsmPrinter &AP) {
1185 const TargetData *TD = AP.TM.getTargetData();
1186 unsigned Size = TD->getTypeAllocSize(CU->getType());
1188 const Constant *Contents = CU->getOperand(0);
1189 unsigned FilledSize = TD->getTypeAllocSize(Contents->getType());
1191 // Print the actually filled part
1192 AP.EmitGlobalConstant(Contents, AddrSpace);
1194 // And pad with enough zeroes
1195 AP.OutStreamer.EmitZeros(Size-FilledSize, AddrSpace);
1198 static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
1200 // FP Constants are printed as integer constants to avoid losing
1202 if (CFP->getType()->isDoubleTy()) {
1203 if (AP.VerboseAsm) {
1204 double Val = CFP->getValueAPF().convertToDouble();
1205 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n';
1208 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1209 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1213 if (CFP->getType()->isFloatTy()) {
1214 if (AP.VerboseAsm) {
1215 float Val = CFP->getValueAPF().convertToFloat();
1216 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n';
1218 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1219 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace);
1223 if (CFP->getType()->isX86_FP80Ty()) {
1224 // all long double variants are printed as hex
1225 // api needed to prevent premature destruction
1226 APInt API = CFP->getValueAPF().bitcastToAPInt();
1227 const uint64_t *p = API.getRawData();
1228 if (AP.VerboseAsm) {
1229 // Convert to double so we can print the approximate val as a comment.
1230 APFloat DoubleVal = CFP->getValueAPF();
1232 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1234 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= "
1235 << DoubleVal.convertToDouble() << '\n';
1238 if (AP.TM.getTargetData()->isBigEndian()) {
1239 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1240 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1242 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1243 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1246 // Emit the tail padding for the long double.
1247 const TargetData &TD = *AP.TM.getTargetData();
1248 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
1249 TD.getTypeStoreSize(CFP->getType()), AddrSpace);
1253 assert(CFP->getType()->isPPC_FP128Ty() &&
1254 "Floating point constant type not handled");
1255 // All long double variants are printed as hex api needed to prevent
1256 // premature destruction.
1257 APInt API = CFP->getValueAPF().bitcastToAPInt();
1258 const uint64_t *p = API.getRawData();
1259 if (AP.TM.getTargetData()->isBigEndian()) {
1260 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1261 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1263 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1264 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1268 static void EmitGlobalConstantLargeInt(const ConstantInt *CI,
1269 unsigned AddrSpace, AsmPrinter &AP) {
1270 const TargetData *TD = AP.TM.getTargetData();
1271 unsigned BitWidth = CI->getBitWidth();
1272 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
1274 // We don't expect assemblers to support integer data directives
1275 // for more than 64 bits, so we emit the data in at most 64-bit
1276 // quantities at a time.
1277 const uint64_t *RawData = CI->getValue().getRawData();
1278 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1279 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1280 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1284 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1285 void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1286 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) {
1287 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1288 if (Size == 0) Size = 1; // An empty "_foo:" followed by a section is undef.
1289 return OutStreamer.EmitZeros(Size, AddrSpace);
1292 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1293 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1300 OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue());
1301 OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1304 EmitGlobalConstantLargeInt(CI, AddrSpace, *this);
1309 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1310 return EmitGlobalConstantArray(CVA, AddrSpace, *this);
1312 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1313 return EmitGlobalConstantStruct(CVS, AddrSpace, *this);
1315 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1316 return EmitGlobalConstantFP(CFP, AddrSpace, *this);
1318 if (isa<ConstantPointerNull>(CV)) {
1319 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1320 OutStreamer.EmitIntValue(0, Size, AddrSpace);
1324 if (const ConstantUnion *CVU = dyn_cast<ConstantUnion>(CV))
1325 return EmitGlobalConstantUnion(CVU, AddrSpace, *this);
1327 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1328 return EmitGlobalConstantVector(V, AddrSpace, *this);
1330 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1331 // thread the streamer with EmitValue.
1332 OutStreamer.EmitValue(LowerConstant(CV, *this),
1333 TM.getTargetData()->getTypeAllocSize(CV->getType()),
1337 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1338 // Target doesn't support this yet!
1339 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1342 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1344 OS << '+' << Offset;
1345 else if (Offset < 0)
1349 /// PrintSpecial - Print information related to the specified machine instr
1350 /// that is independent of the operand, and may be independent of the instr
1351 /// itself. This can be useful for portably encoding the comment character
1352 /// or other bits of target-specific knowledge into the asmstrings. The
1353 /// syntax used is ${:comment}. Targets can override this to add support
1354 /// for their own strange codes.
1355 void AsmPrinter::PrintSpecial(const MachineInstr *MI, raw_ostream &OS,
1356 const char *Code) const {
1357 if (!strcmp(Code, "private")) {
1358 OS << MAI->getPrivateGlobalPrefix();
1359 } else if (!strcmp(Code, "comment")) {
1360 OS << MAI->getCommentString();
1361 } else if (!strcmp(Code, "uid")) {
1362 // Comparing the address of MI isn't sufficient, because machineinstrs may
1363 // be allocated to the same address across functions.
1364 const Function *ThisF = MI->getParent()->getParent()->getFunction();
1366 // If this is a new LastFn instruction, bump the counter.
1367 if (LastMI != MI || LastFn != ThisF) {
1375 raw_string_ostream Msg(msg);
1376 Msg << "Unknown special formatter '" << Code
1377 << "' for machine instr: " << *MI;
1378 llvm_report_error(Msg.str());
1382 /// EmitInlineAsm - This method formats and emits the specified machine
1383 /// instruction that is an inline asm.
1384 void AsmPrinter::EmitInlineAsm(const MachineInstr *MI) const {
1385 assert(MI->isInlineAsm() && "printInlineAsm only works on inline asms");
1387 unsigned NumOperands = MI->getNumOperands();
1389 // Count the number of register definitions to find the asm string.
1390 unsigned NumDefs = 0;
1391 for (; MI->getOperand(NumDefs).isReg() && MI->getOperand(NumDefs).isDef();
1393 assert(NumDefs != NumOperands-1 && "No asm string?");
1395 assert(MI->getOperand(NumDefs).isSymbol() && "No asm string?");
1397 // Disassemble the AsmStr, printing out the literal pieces, the operands, etc.
1398 const char *AsmStr = MI->getOperand(NumDefs).getSymbolName();
1400 // If this asmstr is empty, just print the #APP/#NOAPP markers.
1401 // These are useful to see where empty asm's wound up.
1402 if (AsmStr[0] == 0) {
1403 if (!OutStreamer.hasRawTextSupport()) return;
1405 OutStreamer.EmitRawText(Twine("\t")+MAI->getCommentString()+
1406 MAI->getInlineAsmStart());
1407 OutStreamer.EmitRawText(Twine("\t")+MAI->getCommentString()+
1408 MAI->getInlineAsmEnd());
1412 // Emit the #APP start marker. This has to happen even if verbose-asm isn't
1413 // enabled, so we use EmitRawText.
1414 if (OutStreamer.hasRawTextSupport())
1415 OutStreamer.EmitRawText(Twine("\t")+MAI->getCommentString()+
1416 MAI->getInlineAsmStart());
1418 // Emit the inline asm to a temporary string so we can emit it through
1420 SmallString<256> StringData;
1421 raw_svector_ostream OS(StringData);
1425 // The variant of the current asmprinter.
1426 int AsmPrinterVariant = MAI->getAssemblerDialect();
1428 int CurVariant = -1; // The number of the {.|.|.} region we are in.
1429 const char *LastEmitted = AsmStr; // One past the last character emitted.
1431 while (*LastEmitted) {
1432 switch (*LastEmitted) {
1434 // Not a special case, emit the string section literally.
1435 const char *LiteralEnd = LastEmitted+1;
1436 while (*LiteralEnd && *LiteralEnd != '{' && *LiteralEnd != '|' &&
1437 *LiteralEnd != '}' && *LiteralEnd != '$' && *LiteralEnd != '\n')
1439 if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1440 OS.write(LastEmitted, LiteralEnd-LastEmitted);
1441 LastEmitted = LiteralEnd;
1445 ++LastEmitted; // Consume newline character.
1446 OS << '\n'; // Indent code with newline.
1449 ++LastEmitted; // Consume '$' character.
1453 switch (*LastEmitted) {
1454 default: Done = false; break;
1455 case '$': // $$ -> $
1456 if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1458 ++LastEmitted; // Consume second '$' character.
1460 case '(': // $( -> same as GCC's { character.
1461 ++LastEmitted; // Consume '(' character.
1462 if (CurVariant != -1) {
1463 llvm_report_error("Nested variants found in inline asm string: '"
1464 + std::string(AsmStr) + "'");
1466 CurVariant = 0; // We're in the first variant now.
1469 ++LastEmitted; // consume '|' character.
1470 if (CurVariant == -1)
1471 OS << '|'; // this is gcc's behavior for | outside a variant
1473 ++CurVariant; // We're in the next variant.
1475 case ')': // $) -> same as GCC's } char.
1476 ++LastEmitted; // consume ')' character.
1477 if (CurVariant == -1)
1478 OS << '}'; // this is gcc's behavior for } outside a variant
1485 bool HasCurlyBraces = false;
1486 if (*LastEmitted == '{') { // ${variable}
1487 ++LastEmitted; // Consume '{' character.
1488 HasCurlyBraces = true;
1491 // If we have ${:foo}, then this is not a real operand reference, it is a
1492 // "magic" string reference, just like in .td files. Arrange to call
1494 if (HasCurlyBraces && *LastEmitted == ':') {
1496 const char *StrStart = LastEmitted;
1497 const char *StrEnd = strchr(StrStart, '}');
1499 llvm_report_error(Twine("Unterminated ${:foo} operand in inline asm"
1500 " string: '") + Twine(AsmStr) + "'");
1502 std::string Val(StrStart, StrEnd);
1503 PrintSpecial(MI, OS, Val.c_str());
1504 LastEmitted = StrEnd+1;
1508 const char *IDStart = LastEmitted;
1511 long Val = strtol(IDStart, &IDEnd, 10); // We only accept numbers for IDs.
1512 if (!isdigit(*IDStart) || (Val == 0 && errno == EINVAL)) {
1513 llvm_report_error("Bad $ operand number in inline asm string: '"
1514 + std::string(AsmStr) + "'");
1516 LastEmitted = IDEnd;
1518 char Modifier[2] = { 0, 0 };
1520 if (HasCurlyBraces) {
1521 // If we have curly braces, check for a modifier character. This
1522 // supports syntax like ${0:u}, which correspond to "%u0" in GCC asm.
1523 if (*LastEmitted == ':') {
1524 ++LastEmitted; // Consume ':' character.
1525 if (*LastEmitted == 0) {
1526 llvm_report_error("Bad ${:} expression in inline asm string: '"
1527 + std::string(AsmStr) + "'");
1530 Modifier[0] = *LastEmitted;
1531 ++LastEmitted; // Consume modifier character.
1534 if (*LastEmitted != '}') {
1535 llvm_report_error("Bad ${} expression in inline asm string: '"
1536 + std::string(AsmStr) + "'");
1538 ++LastEmitted; // Consume '}' character.
1541 if ((unsigned)Val >= NumOperands-1) {
1542 llvm_report_error("Invalid $ operand number in inline asm string: '"
1543 + std::string(AsmStr) + "'");
1546 // Okay, we finally have a value number. Ask the target to print this
1548 if (CurVariant == -1 || CurVariant == AsmPrinterVariant) {
1553 // Scan to find the machine operand number for the operand.
1554 for (; Val; --Val) {
1555 if (OpNo >= MI->getNumOperands()) break;
1556 unsigned OpFlags = MI->getOperand(OpNo).getImm();
1557 OpNo += InlineAsm::getNumOperandRegisters(OpFlags) + 1;
1560 if (OpNo >= MI->getNumOperands()) {
1563 unsigned OpFlags = MI->getOperand(OpNo).getImm();
1564 ++OpNo; // Skip over the ID number.
1566 if (Modifier[0] == 'l') // labels are target independent
1567 OS << *MI->getOperand(OpNo).getMBB()->getSymbol();
1569 AsmPrinter *AP = const_cast<AsmPrinter*>(this);
1570 if ((OpFlags & 7) == 4) {
1571 Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant,
1572 Modifier[0] ? Modifier : 0,
1575 Error = AP->PrintAsmOperand(MI, OpNo, AsmPrinterVariant,
1576 Modifier[0] ? Modifier : 0, OS);
1582 raw_string_ostream Msg(msg);
1583 Msg << "Invalid operand found in inline asm: '" << AsmStr << "'\n";
1585 llvm_report_error(Msg.str());
1594 EmitInlineAsm(OS.str());
1596 // Emit the #NOAPP end marker. This has to happen even if verbose-asm isn't
1597 // enabled, so we use EmitRawText.
1598 if (OutStreamer.hasRawTextSupport())
1599 OutStreamer.EmitRawText(Twine("\t")+MAI->getCommentString()+
1600 MAI->getInlineAsmEnd());
1603 /// EmitImplicitDef - This method emits the specified machine instruction
1604 /// that is an implicit def.
1605 void AsmPrinter::EmitImplicitDef(const MachineInstr *MI) const {
1606 if (!VerboseAsm) return;
1607 unsigned RegNo = MI->getOperand(0).getReg();
1608 OutStreamer.AddComment(Twine("implicit-def: ") +
1609 TM.getRegisterInfo()->getName(RegNo));
1610 OutStreamer.AddBlankLine();
1613 void AsmPrinter::EmitKill(const MachineInstr *MI) const {
1614 if (!VerboseAsm) return;
1616 std::string Str = "kill:";
1617 for (unsigned n = 0, e = MI->getNumOperands(); n != e; ++n) {
1618 const MachineOperand &Op = MI->getOperand(n);
1619 assert(Op.isReg() && "KILL instruction must have only register operands");
1621 Str += TM.getRegisterInfo()->getName(Op.getReg());
1622 Str += (Op.isDef() ? "<def>" : "<kill>");
1624 OutStreamer.AddComment(Str);
1625 OutStreamer.AddBlankLine();
1628 /// PrintAsmOperand - Print the specified operand of MI, an INLINEASM
1629 /// instruction, using the specified assembler variant. Targets should
1630 /// override this to format as appropriate.
1631 bool AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
1632 unsigned AsmVariant, const char *ExtraCode,
1634 // Target doesn't support this yet!
1638 bool AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
1639 unsigned AsmVariant,
1640 const char *ExtraCode, raw_ostream &O) {
1641 // Target doesn't support this yet!
1645 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
1646 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
1649 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
1650 return MMI->getAddrLabelSymbol(BB);
1653 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1654 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1655 return OutContext.GetOrCreateSymbol
1656 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
1657 + "_" + Twine(CPID));
1660 /// GetJTISymbol - Return the symbol for the specified jump table entry.
1661 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1662 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
1665 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
1666 /// FIXME: privatize to AsmPrinter.
1667 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
1668 return OutContext.GetOrCreateSymbol
1669 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
1670 Twine(UID) + "_set_" + Twine(MBBID));
1673 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1674 /// global value name as its base, with the specified suffix, and where the
1675 /// symbol is forced to have private linkage if ForcePrivate is true.
1676 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1678 bool ForcePrivate) const {
1679 SmallString<60> NameStr;
1680 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1681 NameStr.append(Suffix.begin(), Suffix.end());
1682 return OutContext.GetOrCreateSymbol(NameStr.str());
1685 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
1687 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
1688 SmallString<60> NameStr;
1689 Mang->getNameWithPrefix(NameStr, Sym);
1690 return OutContext.GetOrCreateSymbol(NameStr.str());
1695 /// PrintParentLoopComment - Print comments about parent loops of this one.
1696 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1697 unsigned FunctionNumber) {
1698 if (Loop == 0) return;
1699 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
1700 OS.indent(Loop->getLoopDepth()*2)
1701 << "Parent Loop BB" << FunctionNumber << "_"
1702 << Loop->getHeader()->getNumber()
1703 << " Depth=" << Loop->getLoopDepth() << '\n';
1707 /// PrintChildLoopComment - Print comments about child loops within
1708 /// the loop for this basic block, with nesting.
1709 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1710 unsigned FunctionNumber) {
1711 // Add child loop information
1712 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
1713 OS.indent((*CL)->getLoopDepth()*2)
1714 << "Child Loop BB" << FunctionNumber << "_"
1715 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
1717 PrintChildLoopComment(OS, *CL, FunctionNumber);
1721 /// EmitBasicBlockLoopComments - Pretty-print comments for basic blocks.
1722 static void EmitBasicBlockLoopComments(const MachineBasicBlock &MBB,
1723 const MachineLoopInfo *LI,
1724 const AsmPrinter &AP) {
1725 // Add loop depth information
1726 const MachineLoop *Loop = LI->getLoopFor(&MBB);
1727 if (Loop == 0) return;
1729 MachineBasicBlock *Header = Loop->getHeader();
1730 assert(Header && "No header for loop");
1732 // If this block is not a loop header, just print out what is the loop header
1734 if (Header != &MBB) {
1735 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
1736 Twine(AP.getFunctionNumber())+"_" +
1737 Twine(Loop->getHeader()->getNumber())+
1738 " Depth="+Twine(Loop->getLoopDepth()));
1742 // Otherwise, it is a loop header. Print out information about child and
1744 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
1746 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
1749 OS.indent(Loop->getLoopDepth()*2-2);
1754 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
1756 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
1760 /// EmitBasicBlockStart - This method prints the label for the specified
1761 /// MachineBasicBlock, an alignment (if present) and a comment describing
1762 /// it if appropriate.
1763 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
1764 // Emit an alignment directive for this block, if needed.
1765 if (unsigned Align = MBB->getAlignment())
1766 EmitAlignment(Log2_32(Align));
1768 // If the block has its address taken, emit any labels that were used to
1769 // reference the block. It is possible that there is more than one label
1770 // here, because multiple LLVM BB's may have been RAUW'd to this block after
1771 // the references were generated.
1772 if (MBB->hasAddressTaken()) {
1773 const BasicBlock *BB = MBB->getBasicBlock();
1775 OutStreamer.AddComment("Block address taken");
1777 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
1779 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
1780 OutStreamer.EmitLabel(Syms[i]);
1783 // Print the main label for the block.
1784 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
1785 if (VerboseAsm && OutStreamer.hasRawTextSupport()) {
1786 if (const BasicBlock *BB = MBB->getBasicBlock())
1788 OutStreamer.AddComment("%" + BB->getName());
1790 EmitBasicBlockLoopComments(*MBB, LI, *this);
1792 // NOTE: Want this comment at start of line, don't emit with AddComment.
1793 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" +
1794 Twine(MBB->getNumber()) + ":");
1798 if (const BasicBlock *BB = MBB->getBasicBlock())
1800 OutStreamer.AddComment("%" + BB->getName());
1801 EmitBasicBlockLoopComments(*MBB, LI, *this);
1804 OutStreamer.EmitLabel(MBB->getSymbol());
1808 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility) const {
1809 MCSymbolAttr Attr = MCSA_Invalid;
1811 switch (Visibility) {
1813 case GlobalValue::HiddenVisibility:
1814 Attr = MAI->getHiddenVisibilityAttr();
1816 case GlobalValue::ProtectedVisibility:
1817 Attr = MAI->getProtectedVisibilityAttr();
1821 if (Attr != MCSA_Invalid)
1822 OutStreamer.EmitSymbolAttribute(Sym, Attr);
1825 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
1826 /// exactly one predecessor and the control transfer mechanism between
1827 /// the predecessor and this block is a fall-through.
1829 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
1830 // If this is a landing pad, it isn't a fall through. If it has no preds,
1831 // then nothing falls through to it.
1832 if (MBB->isLandingPad() || MBB->pred_empty())
1835 // If there isn't exactly one predecessor, it can't be a fall through.
1836 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
1838 if (PI2 != MBB->pred_end())
1841 // The predecessor has to be immediately before this block.
1842 const MachineBasicBlock *Pred = *PI;
1844 if (!Pred->isLayoutSuccessor(MBB))
1847 // If the block is completely empty, then it definitely does fall through.
1851 // Otherwise, check the last instruction.
1852 const MachineInstr &LastInst = Pred->back();
1853 return !LastInst.getDesc().isBarrier();
1858 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1859 if (!S->usesMetadata())
1862 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
1863 gcp_map_type::iterator GCPI = GCMap.find(S);
1864 if (GCPI != GCMap.end())
1865 return GCPI->second;
1867 const char *Name = S->getName().c_str();
1869 for (GCMetadataPrinterRegistry::iterator
1870 I = GCMetadataPrinterRegistry::begin(),
1871 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1872 if (strcmp(Name, I->getName()) == 0) {
1873 GCMetadataPrinter *GMP = I->instantiate();
1875 GCMap.insert(std::make_pair(S, GMP));
1879 llvm_report_error("no GCMetadataPrinter registered for GC: " + Twine(Name));