1 //===-- AsmPrinter.cpp - Common AsmPrinter code ---------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the AsmPrinter class.
11 //
12 //===----------------------------------------------------------------------===//
14 #define DEBUG_TYPE "asm-printer"
15 #include "llvm/CodeGen/AsmPrinter.h"
16 #include "DwarfDebug.h"
17 #include "DwarfException.h"
18 #include "llvm/ADT/SmallString.h"
19 #include "llvm/ADT/Statistic.h"
20 #include "llvm/Analysis/ConstantFolding.h"
21 #include "llvm/Assembly/Writer.h"
22 #include "llvm/CodeGen/GCMetadataPrinter.h"
23 #include "llvm/CodeGen/MachineConstantPool.h"
24 #include "llvm/CodeGen/MachineFrameInfo.h"
25 #include "llvm/CodeGen/MachineFunction.h"
26 #include "llvm/CodeGen/MachineJumpTableInfo.h"
27 #include "llvm/CodeGen/MachineLoopInfo.h"
28 #include "llvm/CodeGen/MachineModuleInfo.h"
29 #include "llvm/DebugInfo.h"
30 #include "llvm/IR/DataLayout.h"
31 #include "llvm/IR/Module.h"
32 #include "llvm/IR/Operator.h"
33 #include "llvm/MC/MCAsmInfo.h"
34 #include "llvm/MC/MCContext.h"
35 #include "llvm/MC/MCExpr.h"
36 #include "llvm/MC/MCInst.h"
37 #include "llvm/MC/MCSection.h"
38 #include "llvm/MC/MCStreamer.h"
39 #include "llvm/MC/MCSymbol.h"
40 #include "llvm/Support/ErrorHandling.h"
41 #include "llvm/Support/Format.h"
42 #include "llvm/Support/MathExtras.h"
43 #include "llvm/Support/Timer.h"
44 #include "llvm/Target/Mangler.h"
45 #include "llvm/Target/TargetFrameLowering.h"
46 #include "llvm/Target/TargetInstrInfo.h"
47 #include "llvm/Target/TargetLowering.h"
48 #include "llvm/Target/TargetLoweringObjectFile.h"
49 #include "llvm/Target/TargetOptions.h"
50 #include "llvm/Target/TargetRegisterInfo.h"
51 #include "llvm/Transforms/Utils/GlobalStatus.h"
52 using namespace llvm;
54 static const char *const DWARFGroupName = "DWARF Emission";
55 static const char *const DbgTimerName = "DWARF Debug Writer";
56 static const char *const EHTimerName = "DWARF Exception Writer";
58 STATISTIC(EmittedInsts, "Number of machine instrs printed");
60 char AsmPrinter::ID = 0;
62 typedef DenseMap<GCStrategy*,GCMetadataPrinter*> gcp_map_type;
63 static gcp_map_type &getGCMap(void *&P) {
64 if (P == 0)
65 P = new gcp_map_type();
66 return *(gcp_map_type*)P;
67 }
70 /// getGVAlignmentLog2 - Return the alignment to use for the specified global
71 /// value in log2 form. This rounds up to the preferred alignment if possible
72 /// and legal.
73 static unsigned getGVAlignmentLog2(const GlobalValue *GV, const DataLayout &TD,
74 unsigned InBits = 0) {
75 unsigned NumBits = 0;
76 if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV))
77 NumBits = TD.getPreferredAlignmentLog(GVar);
79 // If InBits is specified, round it to it.
80 if (InBits > NumBits)
81 NumBits = InBits;
83 // If the GV has a specified alignment, take it into account.
84 if (GV->getAlignment() == 0)
85 return NumBits;
87 unsigned GVAlign = Log2_32(GV->getAlignment());
89 // If the GVAlign is larger than NumBits, or if we are required to obey
90 // NumBits because the GV has an assigned section, obey it.
91 if (GVAlign > NumBits || GV->hasSection())
92 NumBits = GVAlign;
93 return NumBits;
94 }
96 AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
97 : MachineFunctionPass(ID),
98 TM(tm), MAI(tm.getMCAsmInfo()), MII(tm.getInstrInfo()),
99 OutContext(Streamer.getContext()),
100 OutStreamer(Streamer),
101 LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {
102 DD = 0; DE = 0; MMI = 0; LI = 0; MF = 0;
103 CurrentFnSym = CurrentFnSymForSize = 0;
104 GCMetadataPrinters = 0;
105 VerboseAsm = Streamer.isVerboseAsm();
106 }
108 AsmPrinter::~AsmPrinter() {
109 assert(DD == 0 && DE == 0 && "Debug/EH info didn't get finalized");
111 if (GCMetadataPrinters != 0) {
112 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
114 for (gcp_map_type::iterator I = GCMap.begin(), E = GCMap.end(); I != E; ++I)
115 delete I->second;
116 delete &GCMap;
117 GCMetadataPrinters = 0;
118 }
120 delete &OutStreamer;
121 }
123 /// getFunctionNumber - Return a unique ID for the current function.
124 ///
125 unsigned AsmPrinter::getFunctionNumber() const {
126 return MF->getFunctionNumber();
127 }
129 const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
130 return TM.getTargetLowering()->getObjFileLowering();
131 }
133 /// getDataLayout - Return information about data layout.
134 const DataLayout &AsmPrinter::getDataLayout() const {
135 return *TM.getDataLayout();
136 }
138 StringRef AsmPrinter::getTargetTriple() const {
139 return TM.getTargetTriple();
140 }
142 /// getCurrentSection() - Return the current section we are emitting to.
143 const MCSection *AsmPrinter::getCurrentSection() const {
144 return OutStreamer.getCurrentSection().first;
145 }
149 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
150 AU.setPreservesAll();
151 MachineFunctionPass::getAnalysisUsage(AU);
152 AU.addRequired<MachineModuleInfo>();
153 AU.addRequired<GCModuleInfo>();
154 if (isVerbose())
155 AU.addRequired<MachineLoopInfo>();
156 }
158 bool AsmPrinter::doInitialization(Module &M) {
159 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
160 MMI->AnalyzeModule(M);
162 // Initialize TargetLoweringObjectFile.
163 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
164 .Initialize(OutContext, TM);
166 OutStreamer.InitStreamer();
168 Mang = new Mangler(&TM);
170 // Allow the target to emit any magic that it wants at the start of the file.
171 EmitStartOfAsmFile(M);
173 // Very minimal debug info. It is ignored if we emit actual debug info. If we
174 // don't, this at least helps the user find where a global came from.
175 if (MAI->hasSingleParameterDotFile()) {
176 // .file "foo.c"
177 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
178 }
180 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
181 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
182 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
183 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
184 MP->beginAssembly(*this);
186 // Emit module-level inline asm if it exists.
187 if (!M.getModuleInlineAsm().empty()) {
188 OutStreamer.AddComment("Start of file scope inline assembly");
189 OutStreamer.AddBlankLine();
190 EmitInlineAsm(M.getModuleInlineAsm()+"\n");
191 OutStreamer.AddComment("End of file scope inline assembly");
192 OutStreamer.AddBlankLine();
193 }
195 if (MAI->doesSupportDebugInformation())
196 DD = new DwarfDebug(this, &M);
198 switch (MAI->getExceptionHandlingType()) {
199 case ExceptionHandling::None:
200 return false;
201 case ExceptionHandling::SjLj:
202 case ExceptionHandling::DwarfCFI:
203 DE = new DwarfCFIException(this);
204 return false;
205 case ExceptionHandling::ARM:
206 DE = new ARMException(this);
207 return false;
208 case ExceptionHandling::Win64:
209 DE = new Win64Exception(this);
210 return false;
211 }
213 llvm_unreachable("Unknown exception type.");
214 }
216 void AsmPrinter::EmitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const {
217 GlobalValue::LinkageTypes Linkage = GV->getLinkage();
218 switch (Linkage) {
219 case GlobalValue::CommonLinkage:
220 case GlobalValue::LinkOnceAnyLinkage:
221 case GlobalValue::LinkOnceODRLinkage:
222 case GlobalValue::LinkOnceODRAutoHideLinkage:
223 case GlobalValue::WeakAnyLinkage:
224 case GlobalValue::WeakODRLinkage:
225 case GlobalValue::LinkerPrivateWeakLinkage:
226 if (MAI->getWeakDefDirective() != 0) {
227 // .globl _foo
228 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
231 bool CanBeHidden = Linkage == GlobalValue::LinkOnceODRAutoHideLinkage;
233 if (!CanBeHidden && Linkage == GlobalValue::LinkOnceODRLinkage) {
234 if (GV->hasUnnamedAddr()) {
235 CanBeHidden = true;
236 } else {
237 GlobalStatus GS;
238 if (!GlobalStatus::analyzeGlobal(GV, GS) && !GS.IsCompared)
239 CanBeHidden = true;
240 }
241 }
243 if (!CanBeHidden)
244 // .weak_definition _foo
245 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
246 else
247 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefAutoPrivate);
248 } else if (MAI->getLinkOnceDirective() != 0) {
249 // .globl _foo
250 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
251 //NOTE: linkonce is handled by the section the symbol was assigned to.
252 } else {
253 // .weak _foo
254 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
255 }
256 return;
257 case GlobalValue::DLLExportLinkage:
258 case GlobalValue::AppendingLinkage:
259 // FIXME: appending linkage variables should go into a section of
260 // their name or something. For now, just emit them as external.
261 case GlobalValue::ExternalLinkage:
262 // If external or appending, declare as a global symbol.
263 // .globl _foo
264 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
265 return;
266 case GlobalValue::PrivateLinkage:
267 case GlobalValue::InternalLinkage:
268 case GlobalValue::LinkerPrivateLinkage:
269 return;
270 case GlobalValue::AvailableExternallyLinkage:
271 llvm_unreachable("Should never emit this");
272 case GlobalValue::DLLImportLinkage:
273 case GlobalValue::ExternalWeakLinkage:
274 llvm_unreachable("Don't know how to emit these");
275 }
276 llvm_unreachable("Unknown linkage type!");
277 }
279 MCSymbol *AsmPrinter::getSymbol(const GlobalValue *GV) const {
280 return getObjFileLowering().getSymbol(*Mang, GV);
281 }
283 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
284 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
285 if (GV->hasInitializer()) {
286 // Check to see if this is a special global used by LLVM, if so, emit it.
287 if (EmitSpecialLLVMGlobal(GV))
288 return;
290 if (isVerbose()) {
291 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
292 /*PrintType=*/false, GV->getParent());
293 OutStreamer.GetCommentOS() << '\n';
294 }
295 }
297 MCSymbol *GVSym = getSymbol(GV);
298 EmitVisibility(GVSym, GV->getVisibility(), !GV->isDeclaration());
300 if (!GV->hasInitializer()) // External globals require no extra code.
301 return;
303 if (MAI->hasDotTypeDotSizeDirective())
304 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
306 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
308 const DataLayout *DL = TM.getDataLayout();
309 uint64_t Size = DL->getTypeAllocSize(GV->getType()->getElementType());
311 // If the alignment is specified, we *must* obey it. Overaligning a global
312 // with a specified alignment is a prompt way to break globals emitted to
313 // sections and expected to be contiguous (e.g. ObjC metadata).
314 unsigned AlignLog = getGVAlignmentLog2(GV, *DL);
316 if (DD)
317 DD->setSymbolSize(GVSym, Size);
319 // Handle common and BSS local symbols (.lcomm).
320 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
321 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
322 unsigned Align = 1 << AlignLog;
324 // Handle common symbols.
325 if (GVKind.isCommon()) {
326 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
327 Align = 0;
329 // .comm _foo, 42, 4
330 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
331 return;
332 }
334 // Handle local BSS symbols.
335 if (MAI->hasMachoZeroFillDirective()) {
336 const MCSection *TheSection =
337 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
338 // .zerofill __DATA, __bss, _foo, 400, 5
339 OutStreamer.EmitZerofill(TheSection, GVSym, Size, Align);
340 return;
341 }
343 // Use .lcomm only if it supports user-specified alignment.
344 // Otherwise, while it would still be correct to use .lcomm in some
345 // cases (e.g. when Align == 1), the external assembler might enfore
346 // some -unknown- default alignment behavior, which could cause
347 // spurious differences between external and integrated assembler.
348 // Prefer to simply fall back to .local / .comm in this case.
349 if (MAI->getLCOMMDirectiveAlignmentType() != LCOMM::NoAlignment) {
350 // .lcomm _foo, 42
351 OutStreamer.EmitLocalCommonSymbol(GVSym, Size, Align);
352 return;
353 }
355 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
356 Align = 0;
358 // .local _foo
359 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
360 // .comm _foo, 42, 4
361 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
362 return;
363 }
365 const MCSection *TheSection =
366 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
368 // Handle the zerofill directive on darwin, which is a special form of BSS
369 // emission.
370 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
371 if (Size == 0) Size = 1; // zerofill of 0 bytes is undefined.
373 // .globl _foo
374 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
375 // .zerofill __DATA, __common, _foo, 400, 5
376 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
377 return;
378 }
380 // Handle thread local data for mach-o which requires us to output an
381 // additional structure of data and mangle the original symbol so that we
382 // can reference it later.
383 //
384 // TODO: This should become an "emit thread local global" method on TLOF.
385 // All of this macho specific stuff should be sunk down into TLOFMachO and
386 // stuff like "TLSExtraDataSection" should no longer be part of the parent
387 // TLOF class. This will also make it more obvious that stuff like
388 // MCStreamer::EmitTBSSSymbol is macho specific and only called from macho
389 // specific code.
390 if (GVKind.isThreadLocal() && MAI->hasMachoTBSSDirective()) {
391 // Emit the .tbss symbol
392 MCSymbol *MangSym =
393 OutContext.GetOrCreateSymbol(GVSym->getName() + Twine("$tlv$init"));
395 if (GVKind.isThreadBSS()) {
396 TheSection = getObjFileLowering().getTLSBSSSection();
397 OutStreamer.EmitTBSSSymbol(TheSection, MangSym, Size, 1 << AlignLog);
398 } else if (GVKind.isThreadData()) {
399 OutStreamer.SwitchSection(TheSection);
401 EmitAlignment(AlignLog, GV);
402 OutStreamer.EmitLabel(MangSym);
404 EmitGlobalConstant(GV->getInitializer());
405 }
407 OutStreamer.AddBlankLine();
409 // Emit the variable struct for the runtime.
410 const MCSection *TLVSect
411 = getObjFileLowering().getTLSExtraDataSection();
413 OutStreamer.SwitchSection(TLVSect);
414 // Emit the linkage here.
415 EmitLinkage(GV, GVSym);
416 OutStreamer.EmitLabel(GVSym);
418 // Three pointers in size:
419 // - __tlv_bootstrap - used to make sure support exists
420 // - spare pointer, used when mapped by the runtime
421 // - pointer to mangled symbol above with initializer
422 unsigned PtrSize = DL->getPointerSizeInBits()/8;
423 OutStreamer.EmitSymbolValue(GetExternalSymbolSymbol("_tlv_bootstrap"),
424 PtrSize);
425 OutStreamer.EmitIntValue(0, PtrSize);
426 OutStreamer.EmitSymbolValue(MangSym, PtrSize);
428 OutStreamer.AddBlankLine();
429 return;
430 }
432 OutStreamer.SwitchSection(TheSection);
434 EmitLinkage(GV, GVSym);
435 EmitAlignment(AlignLog, GV);
437 OutStreamer.EmitLabel(GVSym);
439 EmitGlobalConstant(GV->getInitializer());
441 if (MAI->hasDotTypeDotSizeDirective())
442 // .size foo, 42
443 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
445 OutStreamer.AddBlankLine();
446 }
448 /// EmitFunctionHeader - This method emits the header for the current
449 /// function.
450 void AsmPrinter::EmitFunctionHeader() {
451 // Print out constants referenced by the function
452 EmitConstantPool();
454 // Print the 'header' of function.
455 const Function *F = MF->getFunction();
457 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
458 EmitVisibility(CurrentFnSym, F->getVisibility());
460 EmitLinkage(F, CurrentFnSym);
461 EmitAlignment(MF->getAlignment(), F);
463 if (MAI->hasDotTypeDotSizeDirective())
464 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
466 if (isVerbose()) {
467 WriteAsOperand(OutStreamer.GetCommentOS(), F,
468 /*PrintType=*/false, F->getParent());
469 OutStreamer.GetCommentOS() << '\n';
470 }
472 // Emit the CurrentFnSym. This is a virtual function to allow targets to
473 // do their wild and crazy things as required.
474 EmitFunctionEntryLabel();
476 // If the function had address-taken blocks that got deleted, then we have
477 // references to the dangling symbols. Emit them at the start of the function
478 // so that we don't get references to undefined symbols.
479 std::vector<MCSymbol*> DeadBlockSyms;
480 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
481 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
482 OutStreamer.AddComment("Address taken block that was later removed");
483 OutStreamer.EmitLabel(DeadBlockSyms[i]);
484 }
486 // Emit pre-function debug and/or EH information.
487 if (DE) {
488 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled);
489 DE->BeginFunction(MF);
490 }
491 if (DD) {
492 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
493 DD->beginFunction(MF);
494 }
496 // Emit the prefix data.
497 if (F->hasPrefixData())
498 EmitGlobalConstant(F->getPrefixData());
499 }
501 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
502 /// function. This can be overridden by targets as required to do custom stuff.
503 void AsmPrinter::EmitFunctionEntryLabel() {
504 // The function label could have already been emitted if two symbols end up
505 // conflicting due to asm renaming. Detect this and emit an error.
506 if (CurrentFnSym->isUndefined())
507 return OutStreamer.EmitLabel(CurrentFnSym);
509 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
510 "' label emitted multiple times to assembly file");
511 }
513 /// emitComments - Pretty-print comments for instructions.
514 static void emitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
515 const MachineFunction *MF = MI.getParent()->getParent();
516 const TargetMachine &TM = MF->getTarget();
518 // Check for spills and reloads
519 int FI;
521 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
523 // We assume a single instruction only has a spill or reload, not
524 // both.
525 const MachineMemOperand *MMO;
526 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
527 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
528 MMO = *MI.memoperands_begin();
529 CommentOS << MMO->getSize() << "-byte Reload\n";
530 }
531 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
532 if (FrameInfo->isSpillSlotObjectIndex(FI))
533 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
534 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
535 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
536 MMO = *MI.memoperands_begin();
537 CommentOS << MMO->getSize() << "-byte Spill\n";
538 }
539 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
540 if (FrameInfo->isSpillSlotObjectIndex(FI))
541 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
542 }
544 // Check for spill-induced copies
545 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
546 CommentOS << " Reload Reuse\n";
547 }
549 /// emitImplicitDef - This method emits the specified machine instruction
550 /// that is an implicit def.
551 void AsmPrinter::emitImplicitDef(const MachineInstr *MI) const {
552 unsigned RegNo = MI->getOperand(0).getReg();
553 OutStreamer.AddComment(Twine("implicit-def: ") +
554 TM.getRegisterInfo()->getName(RegNo));
555 OutStreamer.AddBlankLine();
556 }
558 static void emitKill(const MachineInstr *MI, AsmPrinter &AP) {
559 std::string Str = "kill:";
560 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
561 const MachineOperand &Op = MI->getOperand(i);
562 assert(Op.isReg() && "KILL instruction must have only register operands");
563 Str += ' ';
564 Str += AP.TM.getRegisterInfo()->getName(Op.getReg());
565 Str += (Op.isDef() ? "<def>" : "<kill>");
566 }
567 AP.OutStreamer.AddComment(Str);
568 AP.OutStreamer.AddBlankLine();
569 }
571 /// emitDebugValueComment - This method handles the target-independent form
572 /// of DBG_VALUE, returning true if it was able to do so. A false return
573 /// means the target will need to handle MI in EmitInstruction.
574 static bool emitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
575 // This code handles only the 3-operand target-independent form.
576 if (MI->getNumOperands() != 3)
577 return false;
579 SmallString<128> Str;
580 raw_svector_ostream OS(Str);
581 OS << '\t' << AP.MAI->getCommentString() << "DEBUG_VALUE: ";
583 // cast away const; DIetc do not take const operands for some reason.
584 DIVariable V(const_cast<MDNode*>(MI->getOperand(2).getMetadata()));
585 if (V.getContext().isSubprogram()) {
586 StringRef Name = DISubprogram(V.getContext()).getDisplayName();
587 if (!Name.empty())
588 OS << Name << ":";
589 }
590 OS << V.getName() << " <- ";
592 // The second operand is only an offset if it's an immediate.
593 bool Deref = MI->getOperand(0).isReg() && MI->getOperand(1).isImm();
594 int64_t Offset = Deref ? MI->getOperand(1).getImm() : 0;
596 // Register or immediate value. Register 0 means undef.
597 if (MI->getOperand(0).isFPImm()) {
598 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
599 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
600 OS << (double)APF.convertToFloat();
601 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
602 OS << APF.convertToDouble();
603 } else {
604 // There is no good way to print long double. Convert a copy to
605 // double. Ah well, it's only a comment.
606 bool ignored;
607 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
608 &ignored);
609 OS << "(long double) " << APF.convertToDouble();
610 }
611 } else if (MI->getOperand(0).isImm()) {
612 OS << MI->getOperand(0).getImm();
613 } else if (MI->getOperand(0).isCImm()) {
614 MI->getOperand(0).getCImm()->getValue().print(OS, false /*isSigned*/);
615 } else {
616 unsigned Reg;
617 if (MI->getOperand(0).isReg()) {
618 Reg = MI->getOperand(0).getReg();
619 } else {
620 assert(MI->getOperand(0).isFI() && "Unknown operand type");
621 const TargetFrameLowering *TFI = AP.TM.getFrameLowering();
622 Offset += TFI->getFrameIndexReference(*AP.MF,
623 MI->getOperand(0).getIndex(), Reg);
624 Deref = true;
625 }
626 if (Reg == 0) {
627 // Suppress offset, it is not meaningful here.
628 OS << "undef";
629 // NOTE: Want this comment at start of line, don't emit with AddComment.
630 AP.OutStreamer.EmitRawText(OS.str());
631 return true;
632 }
633 if (Deref)
634 OS << '[';
635 OS << AP.TM.getRegisterInfo()->getName(Reg);
636 }
638 if (Deref)
639 OS << '+' << Offset << ']';
641 // NOTE: Want this comment at start of line, don't emit with AddComment.
642 AP.OutStreamer.EmitRawText(OS.str());
643 return true;
644 }
646 AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() {
647 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI &&
648 MF->getFunction()->needsUnwindTableEntry())
649 return CFI_M_EH;
651 if (MMI->hasDebugInfo())
652 return CFI_M_Debug;
654 return CFI_M_None;
655 }
657 bool AsmPrinter::needsSEHMoves() {
658 return MAI->getExceptionHandlingType() == ExceptionHandling::Win64 &&
659 MF->getFunction()->needsUnwindTableEntry();
660 }
662 bool AsmPrinter::needsRelocationsForDwarfStringPool() const {
663 return MAI->doesDwarfUseRelocationsAcrossSections();
664 }
666 void AsmPrinter::emitPrologLabel(const MachineInstr &MI) {
667 const MCSymbol *Label = MI.getOperand(0).getMCSymbol();
669 if (MAI->getExceptionHandlingType() != ExceptionHandling::DwarfCFI)
670 return;
672 if (needsCFIMoves() == CFI_M_None)
673 return;
675 if (MMI->getCompactUnwindEncoding() != 0)
676 OutStreamer.EmitCompactUnwindEncoding(MMI->getCompactUnwindEncoding());
678 const MachineModuleInfo &MMI = MF->getMMI();
679 const std::vector<MCCFIInstruction> &Instrs = MMI.getFrameInstructions();
680 bool FoundOne = false;
681 (void)FoundOne;
682 for (std::vector<MCCFIInstruction>::const_iterator I = Instrs.begin(),
683 E = Instrs.end(); I != E; ++I) {
684 if (I->getLabel() == Label) {
685 emitCFIInstruction(*I);
686 FoundOne = true;
687 }
688 }
689 assert(FoundOne);
690 }
692 /// EmitFunctionBody - This method emits the body and trailer for a
693 /// function.
694 void AsmPrinter::EmitFunctionBody() {
695 // Emit target-specific gunk before the function body.
696 EmitFunctionBodyStart();
698 bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo();
700 // Print out code for the function.
701 bool HasAnyRealCode = false;
702 const MachineInstr *LastMI = 0;
703 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
704 I != E; ++I) {
705 // Print a label for the basic block.
706 EmitBasicBlockStart(I);
707 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
708 II != IE; ++II) {
709 LastMI = II;
711 // Print the assembly for the instruction.
712 if (!II->isLabel() && !II->isImplicitDef() && !II->isKill() &&
713 !II->isDebugValue()) {
714 HasAnyRealCode = true;
715 ++EmittedInsts;
716 }
718 if (ShouldPrintDebugScopes) {
719 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
720 DD->beginInstruction(II);
721 }
723 if (isVerbose())
724 emitComments(*II, OutStreamer.GetCommentOS());
726 switch (II->getOpcode()) {
727 case TargetOpcode::PROLOG_LABEL:
728 emitPrologLabel(*II);
729 break;
731 case TargetOpcode::EH_LABEL:
732 case TargetOpcode::GC_LABEL:
733 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol());
734 break;
735 case TargetOpcode::INLINEASM:
736 EmitInlineAsm(II);
737 break;
738 case TargetOpcode::DBG_VALUE:
739 if (isVerbose()) {
740 if (!emitDebugValueComment(II, *this))
741 EmitInstruction(II);
742 }
743 break;
744 case TargetOpcode::IMPLICIT_DEF:
745 if (isVerbose()) emitImplicitDef(II);
746 break;
747 case TargetOpcode::KILL:
748 if (isVerbose()) emitKill(II, *this);
749 break;
750 default:
751 if (!TM.hasMCUseLoc())
752 MCLineEntry::Make(&OutStreamer, getCurrentSection());
754 EmitInstruction(II);
755 break;
756 }
758 if (ShouldPrintDebugScopes) {
759 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
760 DD->endInstruction(II);
761 }
762 }
763 }
765 // If the last instruction was a prolog label, then we have a situation where
766 // we emitted a prolog but no function body. This results in the ending prolog
767 // label equaling the end of function label and an invalid "row" in the
768 // FDE. We need to emit a noop in this situation so that the FDE's rows are
769 // valid.
770 bool RequiresNoop = LastMI && LastMI->isPrologLabel();
772 // If the function is empty and the object file uses .subsections_via_symbols,
773 // then we need to emit *something* to the function body to prevent the
774 // labels from collapsing together. Just emit a noop.
775 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) || RequiresNoop) {
776 MCInst Noop;
777 TM.getInstrInfo()->getNoopForMachoTarget(Noop);
778 if (Noop.getOpcode()) {
779 OutStreamer.AddComment("avoids zero-length function");
780 OutStreamer.EmitInstruction(Noop);
781 } else // Target not mc-ized yet.
782 OutStreamer.EmitRawText(StringRef("\tnop\n"));
783 }
785 const Function *F = MF->getFunction();
786 for (Function::const_iterator i = F->begin(), e = F->end(); i != e; ++i) {
787 const BasicBlock *BB = i;
788 if (!BB->hasAddressTaken())
789 continue;
790 MCSymbol *Sym = GetBlockAddressSymbol(BB);
791 if (Sym->isDefined())
792 continue;
793 OutStreamer.AddComment("Address of block that was removed by CodeGen");
794 OutStreamer.EmitLabel(Sym);
795 }
797 // Emit target-specific gunk after the function body.
798 EmitFunctionBodyEnd();
800 // If the target wants a .size directive for the size of the function, emit
801 // it.
802 if (MAI->hasDotTypeDotSizeDirective()) {
803 // Create a symbol for the end of function, so we can get the size as
804 // difference between the function label and the temp label.
805 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
806 OutStreamer.EmitLabel(FnEndLabel);
808 const MCExpr *SizeExp =
809 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
810 MCSymbolRefExpr::Create(CurrentFnSymForSize,
811 OutContext),
812 OutContext);
813 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
814 }
816 // Emit post-function debug information.
817 if (DD) {
818 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
819 DD->endFunction(MF);
820 }
821 if (DE) {
822 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled);
823 DE->EndFunction();
824 }
825 MMI->EndFunction();
827 // Print out jump tables referenced by the function.
828 EmitJumpTableInfo();
830 OutStreamer.AddBlankLine();
831 }
833 /// EmitDwarfRegOp - Emit dwarf register operation.
834 void AsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc,
835 bool Indirect) const {
836 const TargetRegisterInfo *TRI = TM.getRegisterInfo();
837 int Reg = TRI->getDwarfRegNum(MLoc.getReg(), false);
839 for (MCSuperRegIterator SR(MLoc.getReg(), TRI); SR.isValid() && Reg < 0;
840 ++SR) {
841 Reg = TRI->getDwarfRegNum(*SR, false);
842 // FIXME: Get the bit range this register uses of the superregister
843 // so that we can produce a DW_OP_bit_piece
844 }
846 // FIXME: Handle cases like a super register being encoded as
847 // DW_OP_reg 32 DW_OP_piece 4 DW_OP_reg 33
849 // FIXME: We have no reasonable way of handling errors in here. The
850 // caller might be in the middle of an dwarf expression. We should
851 // probably assert that Reg >= 0 once debug info generation is more mature.
853 if (MLoc.isIndirect() || Indirect) {
854 if (Reg < 32) {
855 OutStreamer.AddComment(
856 dwarf::OperationEncodingString(dwarf::DW_OP_breg0 + Reg));
857 EmitInt8(dwarf::DW_OP_breg0 + Reg);
858 } else {
859 OutStreamer.AddComment("DW_OP_bregx");
860 EmitInt8(dwarf::DW_OP_bregx);
861 OutStreamer.AddComment(Twine(Reg));
862 EmitULEB128(Reg);
863 }
864 EmitSLEB128(!MLoc.isIndirect() ? 0 : MLoc.getOffset());
865 if (MLoc.isIndirect() && Indirect)
866 EmitInt8(dwarf::DW_OP_deref);
867 } else {
868 if (Reg < 32) {
869 OutStreamer.AddComment(
870 dwarf::OperationEncodingString(dwarf::DW_OP_reg0 + Reg));
871 EmitInt8(dwarf::DW_OP_reg0 + Reg);
872 } else {
873 OutStreamer.AddComment("DW_OP_regx");
874 EmitInt8(dwarf::DW_OP_regx);
875 OutStreamer.AddComment(Twine(Reg));
876 EmitULEB128(Reg);
877 }
878 }
880 // FIXME: Produce a DW_OP_bit_piece if we used a superregister
881 }
883 bool AsmPrinter::doFinalization(Module &M) {
884 // Emit global variables.
885 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
886 I != E; ++I)
887 EmitGlobalVariable(I);
889 // Emit visibility info for declarations
890 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
891 const Function &F = *I;
892 if (!F.isDeclaration())
893 continue;
894 GlobalValue::VisibilityTypes V = F.getVisibility();
895 if (V == GlobalValue::DefaultVisibility)
896 continue;
898 MCSymbol *Name = getSymbol(&F);
899 EmitVisibility(Name, V, false);
900 }
902 // Emit module flags.
903 SmallVector<Module::ModuleFlagEntry, 8> ModuleFlags;
904 M.getModuleFlagsMetadata(ModuleFlags);
905 if (!ModuleFlags.empty())
906 getObjFileLowering().emitModuleFlags(OutStreamer, ModuleFlags, Mang, TM);
908 // Make sure we wrote out everything we need.
909 OutStreamer.Flush();
911 // Finalize debug and EH information.
912 if (DE) {
913 {
914 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled);
915 DE->EndModule();
916 }
917 delete DE; DE = 0;
918 }
919 if (DD) {
920 {
921 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
922 DD->endModule();
923 }
924 delete DD; DD = 0;
925 }
927 // If the target wants to know about weak references, print them all.
928 if (MAI->getWeakRefDirective()) {
929 // FIXME: This is not lazy, it would be nice to only print weak references
930 // to stuff that is actually used. Note that doing so would require targets
931 // to notice uses in operands (due to constant exprs etc). This should
932 // happen with the MC stuff eventually.
934 // Print out module-level global variables here.
935 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
936 I != E; ++I) {
937 if (!I->hasExternalWeakLinkage()) continue;
938 OutStreamer.EmitSymbolAttribute(getSymbol(I), MCSA_WeakReference);
939 }
941 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
942 if (!I->hasExternalWeakLinkage()) continue;
943 OutStreamer.EmitSymbolAttribute(getSymbol(I), MCSA_WeakReference);
944 }
945 }
947 if (MAI->hasSetDirective()) {
948 OutStreamer.AddBlankLine();
949 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
950 I != E; ++I) {
951 MCSymbol *Name = getSymbol(I);
953 const GlobalValue *GV = I->getAliasedGlobal();
954 MCSymbol *Target = getSymbol(GV);
956 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
957 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
958 else if (I->hasWeakLinkage() || I->hasLinkOnceLinkage())
959 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
960 else
961 assert(I->hasLocalLinkage() && "Invalid alias linkage");
963 EmitVisibility(Name, I->getVisibility());
965 // Emit the directives as assignments aka .set:
966 OutStreamer.EmitAssignment(Name,
967 MCSymbolRefExpr::Create(Target, OutContext));
968 }
969 }
971 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
972 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
973 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
974 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
975 MP->finishAssembly(*this);
977 // Emit llvm.ident metadata in an '.ident' directive.
978 EmitModuleIdents(M);
980 // If we don't have any trampolines, then we don't require stack memory
981 // to be executable. Some targets have a directive to declare this.
982 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
983 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
984 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext))
985 OutStreamer.SwitchSection(S);
987 // Allow the target to emit any magic that it wants at the end of the file,
988 // after everything else has gone out.
989 EmitEndOfAsmFile(M);
991 delete Mang; Mang = 0;
992 MMI = 0;
994 OutStreamer.Finish();
995 OutStreamer.reset();
997 return false;
998 }
1000 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
1001 this->MF = &MF;
1002 // Get the function symbol.
1003 CurrentFnSym = getSymbol(MF.getFunction());
1004 CurrentFnSymForSize = CurrentFnSym;
1006 if (isVerbose())
1007 LI = &getAnalysis<MachineLoopInfo>();
1008 }
1010 namespace {
1011 // SectionCPs - Keep track the alignment, constpool entries per Section.
1012 struct SectionCPs {
1013 const MCSection *S;
1014 unsigned Alignment;
1015 SmallVector<unsigned, 4> CPEs;
1016 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
1017 };
1018 }
1020 /// EmitConstantPool - Print to the current output stream assembly
1021 /// representations of the constants in the constant pool MCP. This is
1022 /// used to print out constants which have been "spilled to memory" by
1023 /// the code generator.
1024 ///
1025 void AsmPrinter::EmitConstantPool() {
1026 const MachineConstantPool *MCP = MF->getConstantPool();
1027 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
1028 if (CP.empty()) return;
1030 // Calculate sections for constant pool entries. We collect entries to go into
1031 // the same section together to reduce amount of section switch statements.
1032 SmallVector<SectionCPs, 4> CPSections;
1033 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
1034 const MachineConstantPoolEntry &CPE = CP[i];
1035 unsigned Align = CPE.getAlignment();
1037 SectionKind Kind;
1038 switch (CPE.getRelocationInfo()) {
1039 default: llvm_unreachable("Unknown section kind");
1040 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
1041 case 1:
1042 Kind = SectionKind::getReadOnlyWithRelLocal();
1043 break;
1044 case 0:
1045 switch (TM.getDataLayout()->getTypeAllocSize(CPE.getType())) {
1046 case 4: Kind = SectionKind::getMergeableConst4(); break;
1047 case 8: Kind = SectionKind::getMergeableConst8(); break;
1048 case 16: Kind = SectionKind::getMergeableConst16();break;
1049 default: Kind = SectionKind::getMergeableConst(); break;
1050 }
1051 }
1053 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
1055 // The number of sections are small, just do a linear search from the
1056 // last section to the first.
1057 bool Found = false;
1058 unsigned SecIdx = CPSections.size();
1059 while (SecIdx != 0) {
1060 if (CPSections[--SecIdx].S == S) {
1061 Found = true;
1062 break;
1063 }
1064 }
1065 if (!Found) {
1066 SecIdx = CPSections.size();
1067 CPSections.push_back(SectionCPs(S, Align));
1068 }
1070 if (Align > CPSections[SecIdx].Alignment)
1071 CPSections[SecIdx].Alignment = Align;
1072 CPSections[SecIdx].CPEs.push_back(i);
1073 }
1075 // Now print stuff into the calculated sections.
1076 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
1077 OutStreamer.SwitchSection(CPSections[i].S);
1078 EmitAlignment(Log2_32(CPSections[i].Alignment));
1080 unsigned Offset = 0;
1081 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
1082 unsigned CPI = CPSections[i].CPEs[j];
1083 MachineConstantPoolEntry CPE = CP[CPI];
1085 // Emit inter-object padding for alignment.
1086 unsigned AlignMask = CPE.getAlignment() - 1;
1087 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
1088 OutStreamer.EmitZeros(NewOffset - Offset);
1090 Type *Ty = CPE.getType();
1091 Offset = NewOffset + TM.getDataLayout()->getTypeAllocSize(Ty);
1092 OutStreamer.EmitLabel(GetCPISymbol(CPI));
1094 if (CPE.isMachineConstantPoolEntry())
1095 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
1096 else
1097 EmitGlobalConstant(CPE.Val.ConstVal);
1098 }
1099 }
1100 }
1102 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
1103 /// by the current function to the current output stream.
1104 ///
1105 void AsmPrinter::EmitJumpTableInfo() {
1106 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1107 if (MJTI == 0) return;
1108 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
1109 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1110 if (JT.empty()) return;
1112 // Pick the directive to use to print the jump table entries, and switch to
1113 // the appropriate section.
1114 const Function *F = MF->getFunction();
1115 bool JTInDiffSection = false;
1116 if (// In PIC mode, we need to emit the jump table to the same section as the
1117 // function body itself, otherwise the label differences won't make sense.
1118 // FIXME: Need a better predicate for this: what about custom entries?
1119 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
1120 // We should also do if the section name is NULL or function is declared
1121 // in discardable section
1122 // FIXME: this isn't the right predicate, should be based on the MCSection
1123 // for the function.
1124 F->isWeakForLinker()) {
1125 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
1126 } else {
1127 // Otherwise, drop it in the readonly section.
1128 const MCSection *ReadOnlySection =
1129 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
1130 OutStreamer.SwitchSection(ReadOnlySection);
1131 JTInDiffSection = true;
1132 }
1134 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getDataLayout())));
1136 // Jump tables in code sections are marked with a data_region directive
1137 // where that's supported.
1138 if (!JTInDiffSection)
1139 OutStreamer.EmitDataRegion(MCDR_DataRegionJT32);
1141 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
1142 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1144 // If this jump table was deleted, ignore it.
1145 if (JTBBs.empty()) continue;
1147 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
1148 // .set directive for each unique entry. This reduces the number of
1149 // relocations the assembler will generate for the jump table.
1150 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
1151 MAI->hasSetDirective()) {
1152 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
1153 const TargetLowering *TLI = TM.getTargetLowering();
1154 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
1155 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
1156 const MachineBasicBlock *MBB = JTBBs[ii];
1157 if (!EmittedSets.insert(MBB)) continue;
1159 // .set LJTSet, LBB32-base
1160 const MCExpr *LHS =
1161 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1162 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
1163 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
1164 }
1165 }
1167 // On some targets (e.g. Darwin) we want to emit two consecutive labels
1168 // before each jump table. The first label is never referenced, but tells
1169 // the assembler and linker the extents of the jump table object. The
1170 // second label is actually referenced by the code.
1171 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
1172 // FIXME: This doesn't have to have any specific name, just any randomly
1173 // named and numbered 'l' label would work. Simplify GetJTISymbol.
1174 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
1176 OutStreamer.EmitLabel(GetJTISymbol(JTI));
1178 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
1179 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
1180 }
1181 if (!JTInDiffSection)
1182 OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
1183 }
1185 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
1186 /// current stream.
1187 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
1188 const MachineBasicBlock *MBB,
1189 unsigned UID) const {
1190 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block");
1191 const MCExpr *Value = 0;
1192 switch (MJTI->getEntryKind()) {
1193 case MachineJumpTableInfo::EK_Inline:
1194 llvm_unreachable("Cannot emit EK_Inline jump table entry");
1195 case MachineJumpTableInfo::EK_Custom32:
1196 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
1197 OutContext);
1198 break;
1199 case MachineJumpTableInfo::EK_BlockAddress:
1200 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
1201 // .word LBB123
1202 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1203 break;
1204 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
1205 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
1206 // with a relocation as gp-relative, e.g.:
1207 // .gprel32 LBB123
1208 MCSymbol *MBBSym = MBB->getSymbol();
1209 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1210 return;
1211 }
1213 case MachineJumpTableInfo::EK_GPRel64BlockAddress: {
1214 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded
1215 // with a relocation as gp-relative, e.g.:
1216 // .gpdword LBB123
1217 MCSymbol *MBBSym = MBB->getSymbol();
1218 OutStreamer.EmitGPRel64Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1219 return;
1220 }
1222 case MachineJumpTableInfo::EK_LabelDifference32: {
1223 // EK_LabelDifference32 - Each entry is the address of the block minus
1224 // the address of the jump table. This is used for PIC jump tables where
1225 // gprel32 is not supported. e.g.:
1226 // .word LBB123 - LJTI1_2
1227 // If the .set directive is supported, this is emitted as:
1228 // .set L4_5_set_123, LBB123 - LJTI1_2
1229 // .word L4_5_set_123
1231 // If we have emitted set directives for the jump table entries, print
1232 // them rather than the entries themselves. If we're emitting PIC, then
1233 // emit the table entries as differences between two text section labels.
1234 if (MAI->hasSetDirective()) {
1235 // If we used .set, reference the .set's symbol.
1236 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
1237 OutContext);
1238 break;
1239 }
1240 // Otherwise, use the difference as the jump table entry.
1241 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1242 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
1243 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
1244 break;
1245 }
1246 }
1248 assert(Value && "Unknown entry kind!");
1250 unsigned EntrySize = MJTI->getEntrySize(*TM.getDataLayout());
1251 OutStreamer.EmitValue(Value, EntrySize);
1252 }
1255 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
1256 /// special global used by LLVM. If so, emit it and return true, otherwise
1257 /// do nothing and return false.
1258 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
1259 if (GV->getName() == "llvm.used") {
1260 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
1261 EmitLLVMUsedList(cast<ConstantArray>(GV->getInitializer()));
1262 return true;
1263 }
1265 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
1266 if (GV->getSection() == "llvm.metadata" ||
1267 GV->hasAvailableExternallyLinkage())
1268 return true;
1270 if (!GV->hasAppendingLinkage()) return false;
1272 assert(GV->hasInitializer() && "Not a special LLVM global!");
1274 if (GV->getName() == "llvm.global_ctors") {
1275 EmitXXStructorList(GV->getInitializer(), /* isCtor */ true);
1277 if (TM.getRelocationModel() == Reloc::Static &&
1278 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1279 StringRef Sym(".constructors_used");
1280 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1281 MCSA_Reference);
1282 }
1283 return true;
1284 }
1286 if (GV->getName() == "llvm.global_dtors") {
1287 EmitXXStructorList(GV->getInitializer(), /* isCtor */ false);
1289 if (TM.getRelocationModel() == Reloc::Static &&
1290 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1291 StringRef Sym(".destructors_used");
1292 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1293 MCSA_Reference);
1294 }
1295 return true;
1296 }
1298 return false;
1299 }
1301 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1302 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1303 /// is true, as being used with this directive.
1304 void AsmPrinter::EmitLLVMUsedList(const ConstantArray *InitList) {
1305 // Should be an array of 'i8*'.
1306 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1307 const GlobalValue *GV =
1308 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1309 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
1310 OutStreamer.EmitSymbolAttribute(getSymbol(GV), MCSA_NoDeadStrip);
1311 }
1312 }
1314 /// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
1315 /// priority.
1316 void AsmPrinter::EmitXXStructorList(const Constant *List, bool isCtor) {
1317 // Should be an array of '{ int, void ()* }' structs. The first value is the
1318 // init priority.
1319 if (!isa<ConstantArray>(List)) return;
1321 // Sanity check the structors list.
1322 const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1323 if (!InitList) return; // Not an array!
1324 StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType());
1325 if (!ETy || ETy->getNumElements() != 2) return; // Not an array of pairs!
1326 if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) ||
1327 !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr).
1329 // Gather the structors in a form that's convenient for sorting by priority.
1330 typedef std::pair<unsigned, Constant *> Structor;
1331 SmallVector<Structor, 8> Structors;
1332 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1333 ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i));
1334 if (!CS) continue; // Malformed.
1335 if (CS->getOperand(1)->isNullValue())
1336 break; // Found a null terminator, skip the rest.
1337 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
1338 if (!Priority) continue; // Malformed.
1339 Structors.push_back(std::make_pair(Priority->getLimitedValue(65535),
1340 CS->getOperand(1)));
1341 }
1343 // Emit the function pointers in the target-specific order
1344 const DataLayout *DL = TM.getDataLayout();
1345 unsigned Align = Log2_32(DL->getPointerPrefAlignment());
1346 std::stable_sort(Structors.begin(), Structors.end(), less_first());
1347 for (unsigned i = 0, e = Structors.size(); i != e; ++i) {
1348 const MCSection *OutputSection =
1349 (isCtor ?
1350 getObjFileLowering().getStaticCtorSection(Structors[i].first) :
1351 getObjFileLowering().getStaticDtorSection(Structors[i].first));
1352 OutStreamer.SwitchSection(OutputSection);
1353 if (OutStreamer.getCurrentSection() != OutStreamer.getPreviousSection())
1354 EmitAlignment(Align);
1355 EmitXXStructor(Structors[i].second);
1356 }
1357 }
1359 void AsmPrinter::EmitModuleIdents(Module &M) {
1360 if (!MAI->hasIdentDirective())
1361 return;
1363 if (const NamedMDNode *NMD = M.getNamedMetadata("llvm.ident")) {
1364 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
1365 const MDNode *N = NMD->getOperand(i);
1366 assert(N->getNumOperands() == 1 &&
1367 "llvm.ident metadata entry can have only one operand");
1368 const MDString *S = cast<MDString>(N->getOperand(0));
1369 OutStreamer.EmitIdent(S->getString());
1370 }
1371 }
1372 }
1374 //===--------------------------------------------------------------------===//
1375 // Emission and print routines
1376 //
1378 /// EmitInt8 - Emit a byte directive and value.
1379 ///
1380 void AsmPrinter::EmitInt8(int Value) const {
1381 OutStreamer.EmitIntValue(Value, 1);
1382 }
1384 /// EmitInt16 - Emit a short directive and value.
1385 ///
1386 void AsmPrinter::EmitInt16(int Value) const {
1387 OutStreamer.EmitIntValue(Value, 2);
1388 }
1390 /// EmitInt32 - Emit a long directive and value.
1391 ///
1392 void AsmPrinter::EmitInt32(int Value) const {
1393 OutStreamer.EmitIntValue(Value, 4);
1394 }
1396 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
1397 /// in bytes of the directive is specified by Size and Hi/Lo specify the
1398 /// labels. This implicitly uses .set if it is available.
1399 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1400 unsigned Size) const {
1401 // Get the Hi-Lo expression.
1402 const MCExpr *Diff =
1403 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1404 MCSymbolRefExpr::Create(Lo, OutContext),
1405 OutContext);
1407 if (!MAI->hasSetDirective()) {
1408 OutStreamer.EmitValue(Diff, Size);
1409 return;
1410 }
1412 // Otherwise, emit with .set (aka assignment).
1413 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1414 OutStreamer.EmitAssignment(SetLabel, Diff);
1415 OutStreamer.EmitSymbolValue(SetLabel, Size);
1416 }
1418 /// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo"
1419 /// where the size in bytes of the directive is specified by Size and Hi/Lo
1420 /// specify the labels. This implicitly uses .set if it is available.
1421 void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset,
1422 const MCSymbol *Lo, unsigned Size)
1423 const {
1425 // Emit Hi+Offset - Lo
1426 // Get the Hi+Offset expression.
1427 const MCExpr *Plus =
1428 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext),
1429 MCConstantExpr::Create(Offset, OutContext),
1430 OutContext);
1432 // Get the Hi+Offset-Lo expression.
1433 const MCExpr *Diff =
1434 MCBinaryExpr::CreateSub(Plus,
1435 MCSymbolRefExpr::Create(Lo, OutContext),
1436 OutContext);
1438 if (!MAI->hasSetDirective())
1439 OutStreamer.EmitValue(Diff, Size);
1440 else {
1441 // Otherwise, emit with .set (aka assignment).
1442 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1443 OutStreamer.EmitAssignment(SetLabel, Diff);
1444 OutStreamer.EmitSymbolValue(SetLabel, Size);
1445 }
1446 }
1448 /// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
1449 /// where the size in bytes of the directive is specified by Size and Label
1450 /// specifies the label. This implicitly uses .set if it is available.
1451 void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset,
1452 unsigned Size, bool IsSectionRelative)
1453 const {
1454 if (MAI->needsDwarfSectionOffsetDirective() && IsSectionRelative) {
1455 OutStreamer.EmitCOFFSecRel32(Label);
1456 return;
1457 }
1459 // Emit Label+Offset (or just Label if Offset is zero)
1460 const MCExpr *Expr = MCSymbolRefExpr::Create(Label, OutContext);
1461 if (Offset)
1462 Expr = MCBinaryExpr::CreateAdd(Expr,
1463 MCConstantExpr::Create(Offset, OutContext),
1464 OutContext);
1466 OutStreamer.EmitValue(Expr, Size);
1467 }
1470 //===----------------------------------------------------------------------===//
1472 // EmitAlignment - Emit an alignment directive to the specified power of
1473 // two boundary. For example, if you pass in 3 here, you will get an 8
1474 // byte alignment. If a global value is specified, and if that global has
1475 // an explicit alignment requested, it will override the alignment request
1476 // if required for correctness.
1477 //
1478 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV) const {
1479 if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getDataLayout(), NumBits);
1481 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.
1483 if (getCurrentSection()->getKind().isText())
1484 OutStreamer.EmitCodeAlignment(1 << NumBits);
1485 else
1486 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
1487 }
1489 //===----------------------------------------------------------------------===//
1490 // Constant emission.
1491 //===----------------------------------------------------------------------===//
1493 /// lowerConstant - Lower the specified LLVM Constant to an MCExpr.
1494 ///
1495 static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP) {
1496 MCContext &Ctx = AP.OutContext;
1498 if (CV->isNullValue() || isa<UndefValue>(CV))
1499 return MCConstantExpr::Create(0, Ctx);
1501 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1502 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1504 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1505 return MCSymbolRefExpr::Create(AP.getSymbol(GV), Ctx);
1507 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1508 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1510 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1511 if (CE == 0) {
1512 llvm_unreachable("Unknown constant value to lower!");
1513 }
1515 switch (CE->getOpcode()) {
1516 default:
1517 // If the code isn't optimized, there may be outstanding folding
1518 // opportunities. Attempt to fold the expression using DataLayout as a
1519 // last resort before giving up.
1520 if (Constant *C =
1521 ConstantFoldConstantExpression(CE, AP.TM.getDataLayout()))
1522 if (C != CE)
1523 return lowerConstant(C, AP);
1525 // Otherwise report the problem to the user.
1526 {
1527 std::string S;
1528 raw_string_ostream OS(S);
1529 OS << "Unsupported expression in static initializer: ";
1530 WriteAsOperand(OS, CE, /*PrintType=*/false,
1531 !AP.MF ? 0 : AP.MF->getFunction()->getParent());
1532 report_fatal_error(OS.str());
1533 }
1534 case Instruction::GetElementPtr: {
1535 const DataLayout &DL = *AP.TM.getDataLayout();
1536 // Generate a symbolic expression for the byte address
1537 APInt OffsetAI(DL.getPointerTypeSizeInBits(CE->getType()), 0);
1538 cast<GEPOperator>(CE)->accumulateConstantOffset(DL, OffsetAI);
1540 const MCExpr *Base = lowerConstant(CE->getOperand(0), AP);
1541 if (!OffsetAI)
1542 return Base;
1544 int64_t Offset = OffsetAI.getSExtValue();
1545 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1546 Ctx);
1547 }
1549 case Instruction::Trunc:
1550 // We emit the value and depend on the assembler to truncate the generated
1551 // expression properly. This is important for differences between
1552 // blockaddress labels. Since the two labels are in the same function, it
1553 // is reasonable to treat their delta as a 32-bit value.
1554 // FALL THROUGH.
1555 case Instruction::BitCast:
1556 return lowerConstant(CE->getOperand(0), AP);
1558 case Instruction::IntToPtr: {
1559 const DataLayout &DL = *AP.TM.getDataLayout();
1560 // Handle casts to pointers by changing them into casts to the appropriate
1561 // integer type. This promotes constant folding and simplifies this code.
1562 Constant *Op = CE->getOperand(0);
1563 Op = ConstantExpr::getIntegerCast(Op, DL.getIntPtrType(CV->getType()),
1564 false/*ZExt*/);
1565 return lowerConstant(Op, AP);
1566 }
1568 case Instruction::PtrToInt: {
1569 const DataLayout &DL = *AP.TM.getDataLayout();
1570 // Support only foldable casts to/from pointers that can be eliminated by
1571 // changing the pointer to the appropriately sized integer type.
1572 Constant *Op = CE->getOperand(0);
1573 Type *Ty = CE->getType();
1575 const MCExpr *OpExpr = lowerConstant(Op, AP);
1577 // We can emit the pointer value into this slot if the slot is an
1578 // integer slot equal to the size of the pointer.
1579 if (DL.getTypeAllocSize(Ty) == DL.getTypeAllocSize(Op->getType()))
1580 return OpExpr;
1582 // Otherwise the pointer is smaller than the resultant integer, mask off
1583 // the high bits so we are sure to get a proper truncation if the input is
1584 // a constant expr.
1585 unsigned InBits = DL.getTypeAllocSizeInBits(Op->getType());
1586 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1587 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1588 }
1590 // The MC library also has a right-shift operator, but it isn't consistently
1591 // signed or unsigned between different targets.
1592 case Instruction::Add:
1593 case Instruction::Sub:
1594 case Instruction::Mul:
1595 case Instruction::SDiv:
1596 case Instruction::SRem:
1597 case Instruction::Shl:
1598 case Instruction::And:
1599 case Instruction::Or:
1600 case Instruction::Xor: {
1601 const MCExpr *LHS = lowerConstant(CE->getOperand(0), AP);
1602 const MCExpr *RHS = lowerConstant(CE->getOperand(1), AP);
1603 switch (CE->getOpcode()) {
1604 default: llvm_unreachable("Unknown binary operator constant cast expr");
1605 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1606 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1607 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1608 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1609 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1610 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1611 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1612 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1613 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1614 }
1615 }
1616 }
1617 }
1619 static void emitGlobalConstantImpl(const Constant *C, AsmPrinter &AP);
1621 /// isRepeatedByteSequence - Determine whether the given value is
1622 /// composed of a repeated sequence of identical bytes and return the
1623 /// byte value. If it is not a repeated sequence, return -1.
1624 static int isRepeatedByteSequence(const ConstantDataSequential *V) {
1625 StringRef Data = V->getRawDataValues();
1626 assert(!Data.empty() && "Empty aggregates should be CAZ node");
1627 char C = Data[0];
1628 for (unsigned i = 1, e = Data.size(); i != e; ++i)
1629 if (Data[i] != C) return -1;
1630 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1.
1631 }
1634 /// isRepeatedByteSequence - Determine whether the given value is
1635 /// composed of a repeated sequence of identical bytes and return the
1636 /// byte value. If it is not a repeated sequence, return -1.
1637 static int isRepeatedByteSequence(const Value *V, TargetMachine &TM) {
1639 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
1640 if (CI->getBitWidth() > 64) return -1;
1642 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(V->getType());
1643 uint64_t Value = CI->getZExtValue();
1645 // Make sure the constant is at least 8 bits long and has a power
1646 // of 2 bit width. This guarantees the constant bit width is
1647 // always a multiple of 8 bits, avoiding issues with padding out
1648 // to Size and other such corner cases.
1649 if (CI->getBitWidth() < 8 || !isPowerOf2_64(CI->getBitWidth())) return -1;
1651 uint8_t Byte = static_cast<uint8_t>(Value);
1653 for (unsigned i = 1; i < Size; ++i) {
1654 Value >>= 8;
1655 if (static_cast<uint8_t>(Value) != Byte) return -1;
1656 }
1657 return Byte;
1658 }
1659 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) {
1660 // Make sure all array elements are sequences of the same repeated
1661 // byte.
1662 assert(CA->getNumOperands() != 0 && "Should be a CAZ");
1663 int Byte = isRepeatedByteSequence(CA->getOperand(0), TM);
1664 if (Byte == -1) return -1;
1666 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i) {
1667 int ThisByte = isRepeatedByteSequence(CA->getOperand(i), TM);
1668 if (ThisByte == -1) return -1;
1669 if (Byte != ThisByte) return -1;
1670 }
1671 return Byte;
1672 }
1674 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V))
1675 return isRepeatedByteSequence(CDS);
1677 return -1;
1678 }
1680 static void emitGlobalConstantDataSequential(const ConstantDataSequential *CDS,
1681 AsmPrinter &AP){
1683 // See if we can aggregate this into a .fill, if so, emit it as such.
1684 int Value = isRepeatedByteSequence(CDS, AP.TM);
1685 if (Value != -1) {
1686 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CDS->getType());
1687 // Don't emit a 1-byte object as a .fill.
1688 if (Bytes > 1)
1689 return AP.OutStreamer.EmitFill(Bytes, Value);
1690 }
1692 // If this can be emitted with .ascii/.asciz, emit it as such.
1693 if (CDS->isString())
1694 return AP.OutStreamer.EmitBytes(CDS->getAsString());
1696 // Otherwise, emit the values in successive locations.
1697 unsigned ElementByteSize = CDS->getElementByteSize();
1698 if (isa<IntegerType>(CDS->getElementType())) {
1699 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1700 if (AP.isVerbose())
1701 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1702 CDS->getElementAsInteger(i));
1703 AP.OutStreamer.EmitIntValue(CDS->getElementAsInteger(i),
1704 ElementByteSize);
1705 }
1706 } else if (ElementByteSize == 4) {
1707 // FP Constants are printed as integer constants to avoid losing
1708 // precision.
1709 assert(CDS->getElementType()->isFloatTy());
1710 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1711 union {
1712 float F;
1713 uint32_t I;
1714 };
1716 F = CDS->getElementAsFloat(i);
1717 if (AP.isVerbose())
1718 AP.OutStreamer.GetCommentOS() << "float " << F << '\n';
1719 AP.OutStreamer.EmitIntValue(I, 4);
1720 }
1721 } else {
1722 assert(CDS->getElementType()->isDoubleTy());
1723 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1724 union {
1725 double F;
1726 uint64_t I;
1727 };
1729 F = CDS->getElementAsDouble(i);
1730 if (AP.isVerbose())
1731 AP.OutStreamer.GetCommentOS() << "double " << F << '\n';
1732 AP.OutStreamer.EmitIntValue(I, 8);
1733 }
1734 }
1736 const DataLayout &DL = *AP.TM.getDataLayout();
1737 unsigned Size = DL.getTypeAllocSize(CDS->getType());
1738 unsigned EmittedSize = DL.getTypeAllocSize(CDS->getType()->getElementType()) *
1739 CDS->getNumElements();
1740 if (unsigned Padding = Size - EmittedSize)
1741 AP.OutStreamer.EmitZeros(Padding);
1743 }
1745 static void emitGlobalConstantArray(const ConstantArray *CA, AsmPrinter &AP) {
1746 // See if we can aggregate some values. Make sure it can be
1747 // represented as a series of bytes of the constant value.
1748 int Value = isRepeatedByteSequence(CA, AP.TM);
1750 if (Value != -1) {
1751 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CA->getType());
1752 AP.OutStreamer.EmitFill(Bytes, Value);
1753 }
1754 else {
1755 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1756 emitGlobalConstantImpl(CA->getOperand(i), AP);
1757 }
1758 }
1760 static void emitGlobalConstantVector(const ConstantVector *CV, AsmPrinter &AP) {
1761 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1762 emitGlobalConstantImpl(CV->getOperand(i), AP);
1764 const DataLayout &DL = *AP.TM.getDataLayout();
1765 unsigned Size = DL.getTypeAllocSize(CV->getType());
1766 unsigned EmittedSize = DL.getTypeAllocSize(CV->getType()->getElementType()) *
1767 CV->getType()->getNumElements();
1768 if (unsigned Padding = Size - EmittedSize)
1769 AP.OutStreamer.EmitZeros(Padding);
1770 }
1772 static void emitGlobalConstantStruct(const ConstantStruct *CS, AsmPrinter &AP) {
1773 // Print the fields in successive locations. Pad to align if needed!
1774 const DataLayout *DL = AP.TM.getDataLayout();
1775 unsigned Size = DL->getTypeAllocSize(CS->getType());
1776 const StructLayout *Layout = DL->getStructLayout(CS->getType());
1777 uint64_t SizeSoFar = 0;
1778 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1779 const Constant *Field = CS->getOperand(i);
1781 // Check if padding is needed and insert one or more 0s.
1782 uint64_t FieldSize = DL->getTypeAllocSize(Field->getType());
1783 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1784 - Layout->getElementOffset(i)) - FieldSize;
1785 SizeSoFar += FieldSize + PadSize;
1787 // Now print the actual field value.
1788 emitGlobalConstantImpl(Field, AP);
1790 // Insert padding - this may include padding to increase the size of the
1791 // current field up to the ABI size (if the struct is not packed) as well
1792 // as padding to ensure that the next field starts at the right offset.
1793 AP.OutStreamer.EmitZeros(PadSize);
1794 }
1795 assert(SizeSoFar == Layout->getSizeInBytes() &&
1796 "Layout of constant struct may be incorrect!");
1797 }
1799 static void emitGlobalConstantFP(const ConstantFP *CFP, AsmPrinter &AP) {
1800 APInt API = CFP->getValueAPF().bitcastToAPInt();
1802 // First print a comment with what we think the original floating-point value
1803 // should have been.
1804 if (AP.isVerbose()) {
1805 SmallString<8> StrVal;
1806 CFP->getValueAPF().toString(StrVal);
1808 CFP->getType()->print(AP.OutStreamer.GetCommentOS());
1809 AP.OutStreamer.GetCommentOS() << ' ' << StrVal << '\n';
1810 }
1812 // Now iterate through the APInt chunks, emitting them in endian-correct
1813 // order, possibly with a smaller chunk at beginning/end (e.g. for x87 80-bit
1814 // floats).
1815 unsigned NumBytes = API.getBitWidth() / 8;
1816 unsigned TrailingBytes = NumBytes % sizeof(uint64_t);
1817 const uint64_t *p = API.getRawData();
1819 // PPC's long double has odd notions of endianness compared to how LLVM
1820 // handles it: p[0] goes first for *big* endian on PPC.
1821 if (AP.TM.getDataLayout()->isBigEndian() != CFP->getType()->isPPC_FP128Ty()) {
1822 int Chunk = API.getNumWords() - 1;
1824 if (TrailingBytes)
1825 AP.OutStreamer.EmitIntValue(p[Chunk--], TrailingBytes);
1827 for (; Chunk >= 0; --Chunk)
1828 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1829 } else {
1830 unsigned Chunk;
1831 for (Chunk = 0; Chunk < NumBytes / sizeof(uint64_t); ++Chunk)
1832 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1834 if (TrailingBytes)
1835 AP.OutStreamer.EmitIntValue(p[Chunk], TrailingBytes);
1836 }
1838 // Emit the tail padding for the long double.
1839 const DataLayout &DL = *AP.TM.getDataLayout();
1840 AP.OutStreamer.EmitZeros(DL.getTypeAllocSize(CFP->getType()) -
1841 DL.getTypeStoreSize(CFP->getType()));
1842 }
1844 static void emitGlobalConstantLargeInt(const ConstantInt *CI, AsmPrinter &AP) {
1845 const DataLayout *DL = AP.TM.getDataLayout();
1846 unsigned BitWidth = CI->getBitWidth();
1848 // Copy the value as we may massage the layout for constants whose bit width
1849 // is not a multiple of 64-bits.
1850 APInt Realigned(CI->getValue());
1851 uint64_t ExtraBits = 0;
1852 unsigned ExtraBitsSize = BitWidth & 63;
1854 if (ExtraBitsSize) {
1855 // The bit width of the data is not a multiple of 64-bits.
1856 // The extra bits are expected to be at the end of the chunk of the memory.
1857 // Little endian:
1858 // * Nothing to be done, just record the extra bits to emit.
1859 // Big endian:
1860 // * Record the extra bits to emit.
1861 // * Realign the raw data to emit the chunks of 64-bits.
1862 if (DL->isBigEndian()) {
1863 // Basically the structure of the raw data is a chunk of 64-bits cells:
1864 // 0 1 BitWidth / 64
1865 // [chunk1][chunk2] ... [chunkN].
1866 // The most significant chunk is chunkN and it should be emitted first.
1867 // However, due to the alignment issue chunkN contains useless bits.
1868 // Realign the chunks so that they contain only useless information:
1869 // ExtraBits 0 1 (BitWidth / 64) - 1
1870 // chu[nk1 chu][nk2 chu] ... [nkN-1 chunkN]
1871 ExtraBits = Realigned.getRawData()[0] &
1872 (((uint64_t)-1) >> (64 - ExtraBitsSize));
1873 Realigned = Realigned.lshr(ExtraBitsSize);
1874 } else
1875 ExtraBits = Realigned.getRawData()[BitWidth / 64];
1876 }
1878 // We don't expect assemblers to support integer data directives
1879 // for more than 64 bits, so we emit the data in at most 64-bit
1880 // quantities at a time.
1881 const uint64_t *RawData = Realigned.getRawData();
1882 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1883 uint64_t Val = DL->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1884 AP.OutStreamer.EmitIntValue(Val, 8);
1885 }
1887 if (ExtraBitsSize) {
1888 // Emit the extra bits after the 64-bits chunks.
1890 // Emit a directive that fills the expected size.
1891 uint64_t Size = AP.TM.getDataLayout()->getTypeAllocSize(CI->getType());
1892 Size -= (BitWidth / 64) * 8;
1893 assert(Size && Size * 8 >= ExtraBitsSize &&
1894 (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize)))
1895 == ExtraBits && "Directive too small for extra bits.");
1896 AP.OutStreamer.EmitIntValue(ExtraBits, Size);
1897 }
1898 }
1900 static void emitGlobalConstantImpl(const Constant *CV, AsmPrinter &AP) {
1901 const DataLayout *DL = AP.TM.getDataLayout();
1902 uint64_t Size = DL->getTypeAllocSize(CV->getType());
1903 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV))
1904 return AP.OutStreamer.EmitZeros(Size);
1906 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1907 switch (Size) {
1908 case 1:
1909 case 2:
1910 case 4:
1911 case 8:
1912 if (AP.isVerbose())
1913 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1914 CI->getZExtValue());
1915 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size);
1916 return;
1917 default:
1918 emitGlobalConstantLargeInt(CI, AP);
1919 return;
1920 }
1921 }
1923 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1924 return emitGlobalConstantFP(CFP, AP);
1926 if (isa<ConstantPointerNull>(CV)) {
1927 AP.OutStreamer.EmitIntValue(0, Size);
1928 return;
1929 }
1931 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV))
1932 return emitGlobalConstantDataSequential(CDS, AP);
1934 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1935 return emitGlobalConstantArray(CVA, AP);
1937 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1938 return emitGlobalConstantStruct(CVS, AP);
1940 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
1941 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
1942 // vectors).
1943 if (CE->getOpcode() == Instruction::BitCast)
1944 return emitGlobalConstantImpl(CE->getOperand(0), AP);
1946 if (Size > 8) {
1947 // If the constant expression's size is greater than 64-bits, then we have
1948 // to emit the value in chunks. Try to constant fold the value and emit it
1949 // that way.
1950 Constant *New = ConstantFoldConstantExpression(CE, DL);
1951 if (New && New != CE)
1952 return emitGlobalConstantImpl(New, AP);
1953 }
1954 }
1956 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1957 return emitGlobalConstantVector(V, AP);
1959 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1960 // thread the streamer with EmitValue.
1961 AP.OutStreamer.EmitValue(lowerConstant(CV, AP), Size);
1962 }
1964 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1965 void AsmPrinter::EmitGlobalConstant(const Constant *CV) {
1966 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(CV->getType());
1967 if (Size)
1968 emitGlobalConstantImpl(CV, *this);
1969 else if (MAI->hasSubsectionsViaSymbols()) {
1970 // If the global has zero size, emit a single byte so that two labels don't
1971 // look like they are at the same location.
1972 OutStreamer.EmitIntValue(0, 1);
1973 }
1974 }
1976 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1977 // Target doesn't support this yet!
1978 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1979 }
1981 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1982 if (Offset > 0)
1983 OS << '+' << Offset;
1984 else if (Offset < 0)
1985 OS << Offset;
1986 }
1988 //===----------------------------------------------------------------------===//
1989 // Symbol Lowering Routines.
1990 //===----------------------------------------------------------------------===//
1992 /// GetTempSymbol - Return the MCSymbol corresponding to the assembler
1993 /// temporary label with the specified stem and unique ID.
1994 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const {
1995 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) +
1996 Name + Twine(ID));
1997 }
1999 /// GetTempSymbol - Return an assembler temporary label with the specified
2000 /// stem.
2001 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const {
2002 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix())+
2003 Name);
2004 }
2007 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
2008 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
2009 }
2011 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
2012 return MMI->getAddrLabelSymbol(BB);
2013 }
2015 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
2016 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
2017 return OutContext.GetOrCreateSymbol
2018 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
2019 + "_" + Twine(CPID));
2020 }
2022 /// GetJTISymbol - Return the symbol for the specified jump table entry.
2023 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
2024 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
2025 }
2027 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
2028 /// FIXME: privatize to AsmPrinter.
2029 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
2030 return OutContext.GetOrCreateSymbol
2031 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
2032 Twine(UID) + "_set_" + Twine(MBBID));
2033 }
2035 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
2036 /// global value name as its base, with the specified suffix, and where the
2037 /// symbol is forced to have private linkage if ForcePrivate is true.
2038 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
2039 StringRef Suffix,
2040 bool ForcePrivate) const {
2041 SmallString<60> NameStr;
2042 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
2043 NameStr.append(Suffix.begin(), Suffix.end());
2044 return OutContext.GetOrCreateSymbol(NameStr.str());
2045 }
2047 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
2048 /// ExternalSymbol.
2049 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
2050 SmallString<60> NameStr;
2051 Mang->getNameWithPrefix(NameStr, Sym);
2052 return OutContext.GetOrCreateSymbol(NameStr.str());
2053 }
2057 /// PrintParentLoopComment - Print comments about parent loops of this one.
2058 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2059 unsigned FunctionNumber) {
2060 if (Loop == 0) return;
2061 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
2062 OS.indent(Loop->getLoopDepth()*2)
2063 << "Parent Loop BB" << FunctionNumber << "_"
2064 << Loop->getHeader()->getNumber()
2065 << " Depth=" << Loop->getLoopDepth() << '\n';
2066 }
2069 /// PrintChildLoopComment - Print comments about child loops within
2070 /// the loop for this basic block, with nesting.
2071 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2072 unsigned FunctionNumber) {
2073 // Add child loop information
2074 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
2075 OS.indent((*CL)->getLoopDepth()*2)
2076 << "Child Loop BB" << FunctionNumber << "_"
2077 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
2078 << '\n';
2079 PrintChildLoopComment(OS, *CL, FunctionNumber);
2080 }
2081 }
2083 /// emitBasicBlockLoopComments - Pretty-print comments for basic blocks.
2084 static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
2085 const MachineLoopInfo *LI,
2086 const AsmPrinter &AP) {
2087 // Add loop depth information
2088 const MachineLoop *Loop = LI->getLoopFor(&MBB);
2089 if (Loop == 0) return;
2091 MachineBasicBlock *Header = Loop->getHeader();
2092 assert(Header && "No header for loop");
2094 // If this block is not a loop header, just print out what is the loop header
2095 // and return.
2096 if (Header != &MBB) {
2097 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
2098 Twine(AP.getFunctionNumber())+"_" +
2099 Twine(Loop->getHeader()->getNumber())+
2100 " Depth="+Twine(Loop->getLoopDepth()));
2101 return;
2102 }
2104 // Otherwise, it is a loop header. Print out information about child and
2105 // parent loops.
2106 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
2108 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
2110 OS << "=>";
2111 OS.indent(Loop->getLoopDepth()*2-2);
2113 OS << "This ";
2114 if (Loop->empty())
2115 OS << "Inner ";
2116 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
2118 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
2119 }
2122 /// EmitBasicBlockStart - This method prints the label for the specified
2123 /// MachineBasicBlock, an alignment (if present) and a comment describing
2124 /// it if appropriate.
2125 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
2126 // Emit an alignment directive for this block, if needed.
2127 if (unsigned Align = MBB->getAlignment())
2128 EmitAlignment(Align);
2130 // If the block has its address taken, emit any labels that were used to
2131 // reference the block. It is possible that there is more than one label
2132 // here, because multiple LLVM BB's may have been RAUW'd to this block after
2133 // the references were generated.
2134 if (MBB->hasAddressTaken()) {
2135 const BasicBlock *BB = MBB->getBasicBlock();
2136 if (isVerbose())
2137 OutStreamer.AddComment("Block address taken");
2139 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
2141 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
2142 OutStreamer.EmitLabel(Syms[i]);
2143 }
2145 // Print some verbose block comments.
2146 if (isVerbose()) {
2147 if (const BasicBlock *BB = MBB->getBasicBlock())
2148 if (BB->hasName())
2149 OutStreamer.AddComment("%" + BB->getName());
2150 emitBasicBlockLoopComments(*MBB, LI, *this);
2151 }
2153 // Print the main label for the block.
2154 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
2155 if (isVerbose() && OutStreamer.hasRawTextSupport()) {
2156 // NOTE: Want this comment at start of line, don't emit with AddComment.
2157 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" +
2158 Twine(MBB->getNumber()) + ":");
2159 }
2160 } else {
2161 OutStreamer.EmitLabel(MBB->getSymbol());
2162 }
2163 }
2165 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility,
2166 bool IsDefinition) const {
2167 MCSymbolAttr Attr = MCSA_Invalid;
2169 switch (Visibility) {
2170 default: break;
2171 case GlobalValue::HiddenVisibility:
2172 if (IsDefinition)
2173 Attr = MAI->getHiddenVisibilityAttr();
2174 else
2175 Attr = MAI->getHiddenDeclarationVisibilityAttr();
2176 break;
2177 case GlobalValue::ProtectedVisibility:
2178 Attr = MAI->getProtectedVisibilityAttr();
2179 break;
2180 }
2182 if (Attr != MCSA_Invalid)
2183 OutStreamer.EmitSymbolAttribute(Sym, Attr);
2184 }
2186 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
2187 /// exactly one predecessor and the control transfer mechanism between
2188 /// the predecessor and this block is a fall-through.
2189 bool AsmPrinter::
2190 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
2191 // If this is a landing pad, it isn't a fall through. If it has no preds,
2192 // then nothing falls through to it.
2193 if (MBB->isLandingPad() || MBB->pred_empty())
2194 return false;
2196 // If there isn't exactly one predecessor, it can't be a fall through.
2197 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
2198 ++PI2;
2199 if (PI2 != MBB->pred_end())
2200 return false;
2202 // The predecessor has to be immediately before this block.
2203 MachineBasicBlock *Pred = *PI;
2205 if (!Pred->isLayoutSuccessor(MBB))
2206 return false;
2208 // If the block is completely empty, then it definitely does fall through.
2209 if (Pred->empty())
2210 return true;
2212 // Check the terminators in the previous blocks
2213 for (MachineBasicBlock::iterator II = Pred->getFirstTerminator(),
2214 IE = Pred->end(); II != IE; ++II) {
2215 MachineInstr &MI = *II;
2217 // If it is not a simple branch, we are in a table somewhere.
2218 if (!MI.isBranch() || MI.isIndirectBranch())
2219 return false;
2221 // If we are the operands of one of the branches, this is not
2222 // a fall through.
2223 for (MachineInstr::mop_iterator OI = MI.operands_begin(),
2224 OE = MI.operands_end(); OI != OE; ++OI) {
2225 const MachineOperand& OP = *OI;
2226 if (OP.isJTI())
2227 return false;
2228 if (OP.isMBB() && OP.getMBB() == MBB)
2229 return false;
2230 }
2231 }
2233 return true;
2234 }
2238 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
2239 if (!S->usesMetadata())
2240 return 0;
2242 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
2243 gcp_map_type::iterator GCPI = GCMap.find(S);
2244 if (GCPI != GCMap.end())
2245 return GCPI->second;
2247 const char *Name = S->getName().c_str();
2249 for (GCMetadataPrinterRegistry::iterator
2250 I = GCMetadataPrinterRegistry::begin(),
2251 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
2252 if (strcmp(Name, I->getName()) == 0) {
2253 GCMetadataPrinter *GMP = I->instantiate();
2254 GMP->S = S;
2255 GCMap.insert(std::make_pair(S, GMP));
2256 return GMP;
2257 }
2259 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));
2260 }