1 //===-- AsmPrinter.cpp - Common AsmPrinter code ---------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the AsmPrinter class.
12 //===----------------------------------------------------------------------===//
14 #define DEBUG_TYPE "asm-printer"
15 #include "llvm/CodeGen/AsmPrinter.h"
16 #include "DwarfDebug.h"
17 #include "DwarfException.h"
18 #include "llvm/ADT/SmallString.h"
19 #include "llvm/ADT/Statistic.h"
20 #include "llvm/Analysis/ConstantFolding.h"
21 #include "llvm/Assembly/Writer.h"
22 #include "llvm/CodeGen/GCMetadataPrinter.h"
23 #include "llvm/CodeGen/MachineConstantPool.h"
24 #include "llvm/CodeGen/MachineFrameInfo.h"
25 #include "llvm/CodeGen/MachineFunction.h"
26 #include "llvm/CodeGen/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/TargetInstrInfo.h"
46 #include "llvm/Target/TargetLowering.h"
47 #include "llvm/Target/TargetLoweringObjectFile.h"
48 #include "llvm/Target/TargetOptions.h"
49 #include "llvm/Target/TargetRegisterInfo.h"
52 static const char *DWARFGroupName = "DWARF Emission";
53 static const char *DbgTimerName = "DWARF Debug Writer";
54 static const char *EHTimerName = "DWARF Exception Writer";
56 STATISTIC(EmittedInsts, "Number of machine instrs printed");
58 char AsmPrinter::ID = 0;
60 typedef DenseMap<GCStrategy*,GCMetadataPrinter*> gcp_map_type;
61 static gcp_map_type &getGCMap(void *&P) {
63 P = new gcp_map_type();
64 return *(gcp_map_type*)P;
68 /// getGVAlignmentLog2 - Return the alignment to use for the specified global
69 /// value in log2 form. This rounds up to the preferred alignment if possible
71 static unsigned getGVAlignmentLog2(const GlobalValue *GV, const DataLayout &TD,
72 unsigned InBits = 0) {
74 if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV))
75 NumBits = TD.getPreferredAlignmentLog(GVar);
77 // If InBits is specified, round it to it.
81 // If the GV has a specified alignment, take it into account.
82 if (GV->getAlignment() == 0)
85 unsigned GVAlign = Log2_32(GV->getAlignment());
87 // If the GVAlign is larger than NumBits, or if we are required to obey
88 // NumBits because the GV has an assigned section, obey it.
89 if (GVAlign > NumBits || GV->hasSection())
94 AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
95 : MachineFunctionPass(ID),
96 TM(tm), MAI(tm.getMCAsmInfo()),
97 OutContext(Streamer.getContext()),
98 OutStreamer(Streamer),
99 LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {
100 DD = 0; DE = 0; MMI = 0; LI = 0;
101 CurrentFnSym = CurrentFnSymForSize = 0;
102 GCMetadataPrinters = 0;
103 VerboseAsm = Streamer.isVerboseAsm();
106 AsmPrinter::~AsmPrinter() {
107 assert(DD == 0 && DE == 0 && "Debug/EH info didn't get finalized");
109 if (GCMetadataPrinters != 0) {
110 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
112 for (gcp_map_type::iterator I = GCMap.begin(), E = GCMap.end(); I != E; ++I)
115 GCMetadataPrinters = 0;
121 /// getFunctionNumber - Return a unique ID for the current function.
123 unsigned AsmPrinter::getFunctionNumber() const {
124 return MF->getFunctionNumber();
127 const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
128 return TM.getTargetLowering()->getObjFileLowering();
131 /// getDataLayout - Return information about data layout.
132 const DataLayout &AsmPrinter::getDataLayout() const {
133 return *TM.getDataLayout();
136 StringRef AsmPrinter::getTargetTriple() const {
137 return TM.getTargetTriple();
140 /// getCurrentSection() - Return the current section we are emitting to.
141 const MCSection *AsmPrinter::getCurrentSection() const {
142 return OutStreamer.getCurrentSection().first;
147 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
148 AU.setPreservesAll();
149 MachineFunctionPass::getAnalysisUsage(AU);
150 AU.addRequired<MachineModuleInfo>();
151 AU.addRequired<GCModuleInfo>();
153 AU.addRequired<MachineLoopInfo>();
156 bool AsmPrinter::doInitialization(Module &M) {
157 OutStreamer.InitStreamer();
159 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
160 MMI->AnalyzeModule(M);
162 // Initialize TargetLoweringObjectFile.
163 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
164 .Initialize(OutContext, TM);
166 Mang = new Mangler(OutContext, *TM.getDataLayout());
168 // Allow the target to emit any magic that it wants at the start of the file.
169 EmitStartOfAsmFile(M);
171 // Very minimal debug info. It is ignored if we emit actual debug info. If we
172 // don't, this at least helps the user find where a global came from.
173 if (MAI->hasSingleParameterDotFile()) {
175 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
178 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
179 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
180 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
181 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
182 MP->beginAssembly(*this);
184 // Emit module-level inline asm if it exists.
185 if (!M.getModuleInlineAsm().empty()) {
186 OutStreamer.AddComment("Start of file scope inline assembly");
187 OutStreamer.AddBlankLine();
188 EmitInlineAsm(M.getModuleInlineAsm()+"\n");
189 OutStreamer.AddComment("End of file scope inline assembly");
190 OutStreamer.AddBlankLine();
193 if (MAI->doesSupportDebugInformation())
194 DD = new DwarfDebug(this, &M);
196 switch (MAI->getExceptionHandlingType()) {
197 case ExceptionHandling::None:
199 case ExceptionHandling::SjLj:
200 case ExceptionHandling::DwarfCFI:
201 DE = new DwarfCFIException(this);
203 case ExceptionHandling::ARM:
204 DE = new ARMException(this);
206 case ExceptionHandling::Win64:
207 DE = new Win64Exception(this);
211 llvm_unreachable("Unknown exception type.");
214 void AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const {
215 switch ((GlobalValue::LinkageTypes)Linkage) {
216 case GlobalValue::CommonLinkage:
217 case GlobalValue::LinkOnceAnyLinkage:
218 case GlobalValue::LinkOnceODRLinkage:
219 case GlobalValue::LinkOnceODRAutoHideLinkage:
220 case GlobalValue::WeakAnyLinkage:
221 case GlobalValue::WeakODRLinkage:
222 case GlobalValue::LinkerPrivateWeakLinkage:
223 if (MAI->getWeakDefDirective() != 0) {
225 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
227 if ((GlobalValue::LinkageTypes)Linkage !=
228 GlobalValue::LinkOnceODRAutoHideLinkage)
229 // .weak_definition _foo
230 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
232 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefAutoPrivate);
233 } else if (MAI->getLinkOnceDirective() != 0) {
235 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
236 //NOTE: linkonce is handled by the section the symbol was assigned to.
239 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
242 case GlobalValue::DLLExportLinkage:
243 case GlobalValue::AppendingLinkage:
244 // FIXME: appending linkage variables should go into a section of
245 // their name or something. For now, just emit them as external.
246 case GlobalValue::ExternalLinkage:
247 // If external or appending, declare as a global symbol.
249 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
251 case GlobalValue::PrivateLinkage:
252 case GlobalValue::InternalLinkage:
253 case GlobalValue::LinkerPrivateLinkage:
256 llvm_unreachable("Unknown linkage type!");
261 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
262 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
263 if (GV->hasInitializer()) {
264 // Check to see if this is a special global used by LLVM, if so, emit it.
265 if (EmitSpecialLLVMGlobal(GV))
269 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
270 /*PrintType=*/false, GV->getParent());
271 OutStreamer.GetCommentOS() << '\n';
275 MCSymbol *GVSym = Mang->getSymbol(GV);
276 EmitVisibility(GVSym, GV->getVisibility(), !GV->isDeclaration());
278 if (!GV->hasInitializer()) // External globals require no extra code.
281 if (MAI->hasDotTypeDotSizeDirective())
282 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
284 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
286 const DataLayout *TD = TM.getDataLayout();
287 uint64_t Size = TD->getTypeAllocSize(GV->getType()->getElementType());
289 // If the alignment is specified, we *must* obey it. Overaligning a global
290 // with a specified alignment is a prompt way to break globals emitted to
291 // sections and expected to be contiguous (e.g. ObjC metadata).
292 unsigned AlignLog = getGVAlignmentLog2(GV, *TD);
294 // Handle common and BSS local symbols (.lcomm).
295 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
296 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
297 unsigned Align = 1 << AlignLog;
299 // Handle common symbols.
300 if (GVKind.isCommon()) {
301 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
305 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
309 // Handle local BSS symbols.
310 if (MAI->hasMachoZeroFillDirective()) {
311 const MCSection *TheSection =
312 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
313 // .zerofill __DATA, __bss, _foo, 400, 5
314 OutStreamer.EmitZerofill(TheSection, GVSym, Size, Align);
318 // Use .lcomm only if it supports user-specified alignment.
319 // Otherwise, while it would still be correct to use .lcomm in some
320 // cases (e.g. when Align == 1), the external assembler might enfore
321 // some -unknown- default alignment behavior, which could cause
322 // spurious differences between external and integrated assembler.
323 // Prefer to simply fall back to .local / .comm in this case.
324 if (MAI->getLCOMMDirectiveAlignmentType() != LCOMM::NoAlignment) {
326 OutStreamer.EmitLocalCommonSymbol(GVSym, Size, Align);
330 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
334 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
336 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
340 const MCSection *TheSection =
341 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
343 // Handle the zerofill directive on darwin, which is a special form of BSS
345 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
346 if (Size == 0) Size = 1; // zerofill of 0 bytes is undefined.
349 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
350 // .zerofill __DATA, __common, _foo, 400, 5
351 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
355 // Handle thread local data for mach-o which requires us to output an
356 // additional structure of data and mangle the original symbol so that we
357 // can reference it later.
359 // TODO: This should become an "emit thread local global" method on TLOF.
360 // All of this macho specific stuff should be sunk down into TLOFMachO and
361 // stuff like "TLSExtraDataSection" should no longer be part of the parent
362 // TLOF class. This will also make it more obvious that stuff like
363 // MCStreamer::EmitTBSSSymbol is macho specific and only called from macho
365 if (GVKind.isThreadLocal() && MAI->hasMachoTBSSDirective()) {
366 // Emit the .tbss symbol
368 OutContext.GetOrCreateSymbol(GVSym->getName() + Twine("$tlv$init"));
370 if (GVKind.isThreadBSS())
371 OutStreamer.EmitTBSSSymbol(TheSection, MangSym, Size, 1 << AlignLog);
372 else if (GVKind.isThreadData()) {
373 OutStreamer.SwitchSection(TheSection);
375 EmitAlignment(AlignLog, GV);
376 OutStreamer.EmitLabel(MangSym);
378 EmitGlobalConstant(GV->getInitializer());
381 OutStreamer.AddBlankLine();
383 // Emit the variable struct for the runtime.
384 const MCSection *TLVSect
385 = getObjFileLowering().getTLSExtraDataSection();
387 OutStreamer.SwitchSection(TLVSect);
388 // Emit the linkage here.
389 EmitLinkage(GV->getLinkage(), GVSym);
390 OutStreamer.EmitLabel(GVSym);
392 // Three pointers in size:
393 // - __tlv_bootstrap - used to make sure support exists
394 // - spare pointer, used when mapped by the runtime
395 // - pointer to mangled symbol above with initializer
396 unsigned PtrSize = TD->getPointerSizeInBits()/8;
397 OutStreamer.EmitSymbolValue(GetExternalSymbolSymbol("_tlv_bootstrap"),
399 OutStreamer.EmitIntValue(0, PtrSize);
400 OutStreamer.EmitSymbolValue(MangSym, PtrSize);
402 OutStreamer.AddBlankLine();
406 OutStreamer.SwitchSection(TheSection);
408 EmitLinkage(GV->getLinkage(), GVSym);
409 EmitAlignment(AlignLog, GV);
411 OutStreamer.EmitLabel(GVSym);
413 EmitGlobalConstant(GV->getInitializer());
415 if (MAI->hasDotTypeDotSizeDirective())
417 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
419 OutStreamer.AddBlankLine();
422 /// EmitFunctionHeader - This method emits the header for the current
424 void AsmPrinter::EmitFunctionHeader() {
425 // Print out constants referenced by the function
428 // Print the 'header' of function.
429 const Function *F = MF->getFunction();
431 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
432 EmitVisibility(CurrentFnSym, F->getVisibility());
434 EmitLinkage(F->getLinkage(), CurrentFnSym);
435 EmitAlignment(MF->getAlignment(), F);
437 if (MAI->hasDotTypeDotSizeDirective())
438 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
441 WriteAsOperand(OutStreamer.GetCommentOS(), F,
442 /*PrintType=*/false, F->getParent());
443 OutStreamer.GetCommentOS() << '\n';
446 // Emit the CurrentFnSym. This is a virtual function to allow targets to
447 // do their wild and crazy things as required.
448 EmitFunctionEntryLabel();
450 // If the function had address-taken blocks that got deleted, then we have
451 // references to the dangling symbols. Emit them at the start of the function
452 // so that we don't get references to undefined symbols.
453 std::vector<MCSymbol*> DeadBlockSyms;
454 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
455 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
456 OutStreamer.AddComment("Address taken block that was later removed");
457 OutStreamer.EmitLabel(DeadBlockSyms[i]);
460 // Add some workaround for linkonce linkage on Cygwin\MinGW.
461 if (MAI->getLinkOnceDirective() != 0 &&
462 (F->hasLinkOnceLinkage() || F->hasWeakLinkage())) {
463 // FIXME: What is this?
465 OutContext.GetOrCreateSymbol(Twine("Lllvm$workaround$fake$stub$")+
466 CurrentFnSym->getName());
467 OutStreamer.EmitLabel(FakeStub);
470 // Emit pre-function debug and/or EH information.
472 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled);
473 DE->BeginFunction(MF);
476 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
477 DD->beginFunction(MF);
481 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
482 /// function. This can be overridden by targets as required to do custom stuff.
483 void AsmPrinter::EmitFunctionEntryLabel() {
484 // The function label could have already been emitted if two symbols end up
485 // conflicting due to asm renaming. Detect this and emit an error.
486 if (CurrentFnSym->isUndefined())
487 return OutStreamer.EmitLabel(CurrentFnSym);
489 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
490 "' label emitted multiple times to assembly file");
493 /// emitComments - Pretty-print comments for instructions.
494 static void emitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
495 const MachineFunction *MF = MI.getParent()->getParent();
496 const TargetMachine &TM = MF->getTarget();
498 // Check for spills and reloads
501 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
503 // We assume a single instruction only has a spill or reload, not
505 const MachineMemOperand *MMO;
506 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
507 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
508 MMO = *MI.memoperands_begin();
509 CommentOS << MMO->getSize() << "-byte Reload\n";
511 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
512 if (FrameInfo->isSpillSlotObjectIndex(FI))
513 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
514 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
515 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
516 MMO = *MI.memoperands_begin();
517 CommentOS << MMO->getSize() << "-byte Spill\n";
519 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
520 if (FrameInfo->isSpillSlotObjectIndex(FI))
521 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
524 // Check for spill-induced copies
525 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
526 CommentOS << " Reload Reuse\n";
529 /// emitImplicitDef - This method emits the specified machine instruction
530 /// that is an implicit def.
531 static void emitImplicitDef(const MachineInstr *MI, AsmPrinter &AP) {
532 unsigned RegNo = MI->getOperand(0).getReg();
533 AP.OutStreamer.AddComment(Twine("implicit-def: ") +
534 AP.TM.getRegisterInfo()->getName(RegNo));
535 AP.OutStreamer.AddBlankLine();
538 static void emitKill(const MachineInstr *MI, AsmPrinter &AP) {
539 std::string Str = "kill:";
540 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
541 const MachineOperand &Op = MI->getOperand(i);
542 assert(Op.isReg() && "KILL instruction must have only register operands");
544 Str += AP.TM.getRegisterInfo()->getName(Op.getReg());
545 Str += (Op.isDef() ? "<def>" : "<kill>");
547 AP.OutStreamer.AddComment(Str);
548 AP.OutStreamer.AddBlankLine();
551 /// emitDebugValueComment - This method handles the target-independent form
552 /// of DBG_VALUE, returning true if it was able to do so. A false return
553 /// means the target will need to handle MI in EmitInstruction.
554 static bool emitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
555 // This code handles only the 3-operand target-independent form.
556 if (MI->getNumOperands() != 3)
559 SmallString<128> Str;
560 raw_svector_ostream OS(Str);
561 OS << '\t' << AP.MAI->getCommentString() << "DEBUG_VALUE: ";
563 // cast away const; DIetc do not take const operands for some reason.
564 DIVariable V(const_cast<MDNode*>(MI->getOperand(2).getMetadata()));
565 if (V.getContext().isSubprogram())
566 OS << DISubprogram(V.getContext()).getDisplayName() << ":";
567 OS << V.getName() << " <- ";
569 // Register or immediate value. Register 0 means undef.
570 if (MI->getOperand(0).isFPImm()) {
571 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
572 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
573 OS << (double)APF.convertToFloat();
574 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
575 OS << APF.convertToDouble();
577 // There is no good way to print long double. Convert a copy to
578 // double. Ah well, it's only a comment.
580 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
582 OS << "(long double) " << APF.convertToDouble();
584 } else if (MI->getOperand(0).isImm()) {
585 OS << MI->getOperand(0).getImm();
586 } else if (MI->getOperand(0).isCImm()) {
587 MI->getOperand(0).getCImm()->getValue().print(OS, false /*isSigned*/);
589 assert(MI->getOperand(0).isReg() && "Unknown operand type");
590 if (MI->getOperand(0).getReg() == 0) {
591 // Suppress offset, it is not meaningful here.
593 // NOTE: Want this comment at start of line, don't emit with AddComment.
594 AP.OutStreamer.EmitRawText(OS.str());
597 OS << AP.TM.getRegisterInfo()->getName(MI->getOperand(0).getReg());
600 // It's only an offset if it's an immediate.
601 if (MI->getOperand(1).isImm())
602 OS << '+' << MI->getOperand(1).getImm();
603 // NOTE: Want this comment at start of line, don't emit with AddComment.
604 AP.OutStreamer.EmitRawText(OS.str());
608 AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() {
609 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI &&
610 MF->getFunction()->needsUnwindTableEntry())
613 if (MMI->hasDebugInfo())
619 bool AsmPrinter::needsSEHMoves() {
620 return MAI->getExceptionHandlingType() == ExceptionHandling::Win64 &&
621 MF->getFunction()->needsUnwindTableEntry();
624 bool AsmPrinter::needsRelocationsForDwarfStringPool() const {
625 return MAI->doesDwarfUseRelocationsAcrossSections();
628 void AsmPrinter::emitPrologLabel(const MachineInstr &MI) {
629 MCSymbol *Label = MI.getOperand(0).getMCSymbol();
631 if (MAI->getExceptionHandlingType() != ExceptionHandling::DwarfCFI)
634 if (needsCFIMoves() == CFI_M_None)
637 if (MMI->getCompactUnwindEncoding() != 0)
638 OutStreamer.EmitCompactUnwindEncoding(MMI->getCompactUnwindEncoding());
640 MachineModuleInfo &MMI = MF->getMMI();
641 std::vector<MachineMove> &Moves = MMI.getFrameMoves();
642 bool FoundOne = false;
644 for (std::vector<MachineMove>::iterator I = Moves.begin(),
645 E = Moves.end(); I != E; ++I) {
646 if (I->getLabel() == Label) {
647 EmitCFIFrameMove(*I);
654 /// EmitFunctionBody - This method emits the body and trailer for a
656 void AsmPrinter::EmitFunctionBody() {
657 // Emit target-specific gunk before the function body.
658 EmitFunctionBodyStart();
660 bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo();
662 // Print out code for the function.
663 bool HasAnyRealCode = false;
664 const MachineInstr *LastMI = 0;
665 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
667 // Print a label for the basic block.
668 EmitBasicBlockStart(I);
669 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
673 // Print the assembly for the instruction.
674 if (!II->isLabel() && !II->isImplicitDef() && !II->isKill() &&
675 !II->isDebugValue()) {
676 HasAnyRealCode = true;
680 if (ShouldPrintDebugScopes) {
681 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
682 DD->beginInstruction(II);
686 emitComments(*II, OutStreamer.GetCommentOS());
688 switch (II->getOpcode()) {
689 case TargetOpcode::PROLOG_LABEL:
690 emitPrologLabel(*II);
693 case TargetOpcode::EH_LABEL:
694 case TargetOpcode::GC_LABEL:
695 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol());
697 case TargetOpcode::INLINEASM:
700 case TargetOpcode::DBG_VALUE:
702 if (!emitDebugValueComment(II, *this))
706 case TargetOpcode::IMPLICIT_DEF:
707 if (isVerbose()) emitImplicitDef(II, *this);
709 case TargetOpcode::KILL:
710 if (isVerbose()) emitKill(II, *this);
713 if (!TM.hasMCUseLoc())
714 MCLineEntry::Make(&OutStreamer, getCurrentSection());
720 if (ShouldPrintDebugScopes) {
721 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
722 DD->endInstruction(II);
727 // If the last instruction was a prolog label, then we have a situation where
728 // we emitted a prolog but no function body. This results in the ending prolog
729 // label equaling the end of function label and an invalid "row" in the
730 // FDE. We need to emit a noop in this situation so that the FDE's rows are
732 bool RequiresNoop = LastMI && LastMI->isPrologLabel();
734 // If the function is empty and the object file uses .subsections_via_symbols,
735 // then we need to emit *something* to the function body to prevent the
736 // labels from collapsing together. Just emit a noop.
737 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) || RequiresNoop) {
739 TM.getInstrInfo()->getNoopForMachoTarget(Noop);
740 if (Noop.getOpcode()) {
741 OutStreamer.AddComment("avoids zero-length function");
742 OutStreamer.EmitInstruction(Noop);
743 } else // Target not mc-ized yet.
744 OutStreamer.EmitRawText(StringRef("\tnop\n"));
747 const Function *F = MF->getFunction();
748 for (Function::const_iterator i = F->begin(), e = F->end(); i != e; ++i) {
749 const BasicBlock *BB = i;
750 if (!BB->hasAddressTaken())
752 MCSymbol *Sym = GetBlockAddressSymbol(BB);
753 if (Sym->isDefined())
755 OutStreamer.AddComment("Address of block that was removed by CodeGen");
756 OutStreamer.EmitLabel(Sym);
759 // Emit target-specific gunk after the function body.
760 EmitFunctionBodyEnd();
762 // If the target wants a .size directive for the size of the function, emit
764 if (MAI->hasDotTypeDotSizeDirective()) {
765 // Create a symbol for the end of function, so we can get the size as
766 // difference between the function label and the temp label.
767 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
768 OutStreamer.EmitLabel(FnEndLabel);
770 const MCExpr *SizeExp =
771 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
772 MCSymbolRefExpr::Create(CurrentFnSymForSize,
775 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
778 // Emit post-function debug information.
780 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
784 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled);
789 // Print out jump tables referenced by the function.
792 OutStreamer.AddBlankLine();
795 /// getDebugValueLocation - Get location information encoded by DBG_VALUE
797 MachineLocation AsmPrinter::
798 getDebugValueLocation(const MachineInstr *MI) const {
799 // Target specific DBG_VALUE instructions are handled by each target.
800 return MachineLocation();
803 /// EmitDwarfRegOp - Emit dwarf register operation.
804 void AsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc) const {
805 const TargetRegisterInfo *TRI = TM.getRegisterInfo();
806 int Reg = TRI->getDwarfRegNum(MLoc.getReg(), false);
808 for (MCSuperRegIterator SR(MLoc.getReg(), TRI); SR.isValid() && Reg < 0;
810 Reg = TRI->getDwarfRegNum(*SR, false);
811 // FIXME: Get the bit range this register uses of the superregister
812 // so that we can produce a DW_OP_bit_piece
815 // FIXME: Handle cases like a super register being encoded as
816 // DW_OP_reg 32 DW_OP_piece 4 DW_OP_reg 33
818 // FIXME: We have no reasonable way of handling errors in here. The
819 // caller might be in the middle of an dwarf expression. We should
820 // probably assert that Reg >= 0 once debug info generation is more mature.
822 if (MLoc.isIndirect()) {
824 OutStreamer.AddComment(
825 dwarf::OperationEncodingString(dwarf::DW_OP_breg0 + Reg));
826 EmitInt8(dwarf::DW_OP_breg0 + Reg);
828 OutStreamer.AddComment("DW_OP_bregx");
829 EmitInt8(dwarf::DW_OP_bregx);
830 OutStreamer.AddComment(Twine(Reg));
833 EmitSLEB128(MLoc.getOffset());
836 OutStreamer.AddComment(
837 dwarf::OperationEncodingString(dwarf::DW_OP_reg0 + Reg));
838 EmitInt8(dwarf::DW_OP_reg0 + Reg);
840 OutStreamer.AddComment("DW_OP_regx");
841 EmitInt8(dwarf::DW_OP_regx);
842 OutStreamer.AddComment(Twine(Reg));
847 // FIXME: Produce a DW_OP_bit_piece if we used a superregister
850 bool AsmPrinter::doFinalization(Module &M) {
851 // Emit global variables.
852 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
854 EmitGlobalVariable(I);
856 // Emit visibility info for declarations
857 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
858 const Function &F = *I;
859 if (!F.isDeclaration())
861 GlobalValue::VisibilityTypes V = F.getVisibility();
862 if (V == GlobalValue::DefaultVisibility)
865 MCSymbol *Name = Mang->getSymbol(&F);
866 EmitVisibility(Name, V, false);
869 // Emit module flags.
870 SmallVector<Module::ModuleFlagEntry, 8> ModuleFlags;
871 M.getModuleFlagsMetadata(ModuleFlags);
872 if (!ModuleFlags.empty())
873 getObjFileLowering().emitModuleFlags(OutStreamer, ModuleFlags, Mang, TM);
875 // Finalize debug and EH information.
878 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled);
885 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
891 // If the target wants to know about weak references, print them all.
892 if (MAI->getWeakRefDirective()) {
893 // FIXME: This is not lazy, it would be nice to only print weak references
894 // to stuff that is actually used. Note that doing so would require targets
895 // to notice uses in operands (due to constant exprs etc). This should
896 // happen with the MC stuff eventually.
898 // Print out module-level global variables here.
899 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
901 if (!I->hasExternalWeakLinkage()) continue;
902 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
905 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
906 if (!I->hasExternalWeakLinkage()) continue;
907 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
911 if (MAI->hasSetDirective()) {
912 OutStreamer.AddBlankLine();
913 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
915 MCSymbol *Name = Mang->getSymbol(I);
917 const GlobalValue *GV = I->getAliasedGlobal();
918 MCSymbol *Target = Mang->getSymbol(GV);
920 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
921 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
922 else if (I->hasWeakLinkage())
923 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
925 assert(I->hasLocalLinkage() && "Invalid alias linkage");
927 EmitVisibility(Name, I->getVisibility());
929 // Emit the directives as assignments aka .set:
930 OutStreamer.EmitAssignment(Name,
931 MCSymbolRefExpr::Create(Target, OutContext));
935 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
936 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
937 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
938 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
939 MP->finishAssembly(*this);
941 // If we don't have any trampolines, then we don't require stack memory
942 // to be executable. Some targets have a directive to declare this.
943 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
944 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
945 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext))
946 OutStreamer.SwitchSection(S);
948 // Allow the target to emit any magic that it wants at the end of the file,
949 // after everything else has gone out.
952 delete Mang; Mang = 0;
955 OutStreamer.Finish();
961 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
963 // Get the function symbol.
964 CurrentFnSym = Mang->getSymbol(MF.getFunction());
965 CurrentFnSymForSize = CurrentFnSym;
968 LI = &getAnalysis<MachineLoopInfo>();
972 // SectionCPs - Keep track the alignment, constpool entries per Section.
976 SmallVector<unsigned, 4> CPEs;
977 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
981 /// EmitConstantPool - Print to the current output stream assembly
982 /// representations of the constants in the constant pool MCP. This is
983 /// used to print out constants which have been "spilled to memory" by
984 /// the code generator.
986 void AsmPrinter::EmitConstantPool() {
987 const MachineConstantPool *MCP = MF->getConstantPool();
988 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
989 if (CP.empty()) return;
991 // Calculate sections for constant pool entries. We collect entries to go into
992 // the same section together to reduce amount of section switch statements.
993 SmallVector<SectionCPs, 4> CPSections;
994 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
995 const MachineConstantPoolEntry &CPE = CP[i];
996 unsigned Align = CPE.getAlignment();
999 switch (CPE.getRelocationInfo()) {
1000 default: llvm_unreachable("Unknown section kind");
1001 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
1003 Kind = SectionKind::getReadOnlyWithRelLocal();
1006 switch (TM.getDataLayout()->getTypeAllocSize(CPE.getType())) {
1007 case 4: Kind = SectionKind::getMergeableConst4(); break;
1008 case 8: Kind = SectionKind::getMergeableConst8(); break;
1009 case 16: Kind = SectionKind::getMergeableConst16();break;
1010 default: Kind = SectionKind::getMergeableConst(); break;
1014 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
1016 // The number of sections are small, just do a linear search from the
1017 // last section to the first.
1019 unsigned SecIdx = CPSections.size();
1020 while (SecIdx != 0) {
1021 if (CPSections[--SecIdx].S == S) {
1027 SecIdx = CPSections.size();
1028 CPSections.push_back(SectionCPs(S, Align));
1031 if (Align > CPSections[SecIdx].Alignment)
1032 CPSections[SecIdx].Alignment = Align;
1033 CPSections[SecIdx].CPEs.push_back(i);
1036 // Now print stuff into the calculated sections.
1037 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
1038 OutStreamer.SwitchSection(CPSections[i].S);
1039 EmitAlignment(Log2_32(CPSections[i].Alignment));
1041 unsigned Offset = 0;
1042 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
1043 unsigned CPI = CPSections[i].CPEs[j];
1044 MachineConstantPoolEntry CPE = CP[CPI];
1046 // Emit inter-object padding for alignment.
1047 unsigned AlignMask = CPE.getAlignment() - 1;
1048 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
1049 OutStreamer.EmitZeros(NewOffset - Offset);
1051 Type *Ty = CPE.getType();
1052 Offset = NewOffset + TM.getDataLayout()->getTypeAllocSize(Ty);
1053 OutStreamer.EmitLabel(GetCPISymbol(CPI));
1055 if (CPE.isMachineConstantPoolEntry())
1056 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
1058 EmitGlobalConstant(CPE.Val.ConstVal);
1063 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
1064 /// by the current function to the current output stream.
1066 void AsmPrinter::EmitJumpTableInfo() {
1067 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1068 if (MJTI == 0) return;
1069 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
1070 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1071 if (JT.empty()) return;
1073 // Pick the directive to use to print the jump table entries, and switch to
1074 // the appropriate section.
1075 const Function *F = MF->getFunction();
1076 bool JTInDiffSection = false;
1077 if (// In PIC mode, we need to emit the jump table to the same section as the
1078 // function body itself, otherwise the label differences won't make sense.
1079 // FIXME: Need a better predicate for this: what about custom entries?
1080 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
1081 // We should also do if the section name is NULL or function is declared
1082 // in discardable section
1083 // FIXME: this isn't the right predicate, should be based on the MCSection
1084 // for the function.
1085 F->isWeakForLinker()) {
1086 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
1088 // Otherwise, drop it in the readonly section.
1089 const MCSection *ReadOnlySection =
1090 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
1091 OutStreamer.SwitchSection(ReadOnlySection);
1092 JTInDiffSection = true;
1095 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getDataLayout())));
1097 // Jump tables in code sections are marked with a data_region directive
1098 // where that's supported.
1099 if (!JTInDiffSection)
1100 OutStreamer.EmitDataRegion(MCDR_DataRegionJT32);
1102 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
1103 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1105 // If this jump table was deleted, ignore it.
1106 if (JTBBs.empty()) continue;
1108 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
1109 // .set directive for each unique entry. This reduces the number of
1110 // relocations the assembler will generate for the jump table.
1111 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
1112 MAI->hasSetDirective()) {
1113 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
1114 const TargetLowering *TLI = TM.getTargetLowering();
1115 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
1116 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
1117 const MachineBasicBlock *MBB = JTBBs[ii];
1118 if (!EmittedSets.insert(MBB)) continue;
1120 // .set LJTSet, LBB32-base
1122 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1123 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
1124 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
1128 // On some targets (e.g. Darwin) we want to emit two consecutive labels
1129 // before each jump table. The first label is never referenced, but tells
1130 // the assembler and linker the extents of the jump table object. The
1131 // second label is actually referenced by the code.
1132 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
1133 // FIXME: This doesn't have to have any specific name, just any randomly
1134 // named and numbered 'l' label would work. Simplify GetJTISymbol.
1135 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
1137 OutStreamer.EmitLabel(GetJTISymbol(JTI));
1139 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
1140 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
1142 if (!JTInDiffSection)
1143 OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
1146 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
1148 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
1149 const MachineBasicBlock *MBB,
1150 unsigned UID) const {
1151 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block");
1152 const MCExpr *Value = 0;
1153 switch (MJTI->getEntryKind()) {
1154 case MachineJumpTableInfo::EK_Inline:
1155 llvm_unreachable("Cannot emit EK_Inline jump table entry");
1156 case MachineJumpTableInfo::EK_Custom32:
1157 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
1160 case MachineJumpTableInfo::EK_BlockAddress:
1161 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
1163 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1165 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
1166 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
1167 // with a relocation as gp-relative, e.g.:
1169 MCSymbol *MBBSym = MBB->getSymbol();
1170 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1174 case MachineJumpTableInfo::EK_GPRel64BlockAddress: {
1175 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded
1176 // with a relocation as gp-relative, e.g.:
1178 MCSymbol *MBBSym = MBB->getSymbol();
1179 OutStreamer.EmitGPRel64Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1183 case MachineJumpTableInfo::EK_LabelDifference32: {
1184 // EK_LabelDifference32 - Each entry is the address of the block minus
1185 // the address of the jump table. This is used for PIC jump tables where
1186 // gprel32 is not supported. e.g.:
1187 // .word LBB123 - LJTI1_2
1188 // If the .set directive is supported, this is emitted as:
1189 // .set L4_5_set_123, LBB123 - LJTI1_2
1190 // .word L4_5_set_123
1192 // If we have emitted set directives for the jump table entries, print
1193 // them rather than the entries themselves. If we're emitting PIC, then
1194 // emit the table entries as differences between two text section labels.
1195 if (MAI->hasSetDirective()) {
1196 // If we used .set, reference the .set's symbol.
1197 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
1201 // Otherwise, use the difference as the jump table entry.
1202 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1203 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
1204 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
1209 assert(Value && "Unknown entry kind!");
1211 unsigned EntrySize = MJTI->getEntrySize(*TM.getDataLayout());
1212 OutStreamer.EmitValue(Value, EntrySize);
1216 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
1217 /// special global used by LLVM. If so, emit it and return true, otherwise
1218 /// do nothing and return false.
1219 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
1220 if (GV->getName() == "llvm.used") {
1221 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
1222 EmitLLVMUsedList(cast<ConstantArray>(GV->getInitializer()));
1226 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
1227 if (GV->getSection() == "llvm.metadata" ||
1228 GV->hasAvailableExternallyLinkage())
1231 if (!GV->hasAppendingLinkage()) return false;
1233 assert(GV->hasInitializer() && "Not a special LLVM global!");
1235 if (GV->getName() == "llvm.global_ctors") {
1236 EmitXXStructorList(GV->getInitializer(), /* isCtor */ true);
1238 if (TM.getRelocationModel() == Reloc::Static &&
1239 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1240 StringRef Sym(".constructors_used");
1241 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1247 if (GV->getName() == "llvm.global_dtors") {
1248 EmitXXStructorList(GV->getInitializer(), /* isCtor */ false);
1250 if (TM.getRelocationModel() == Reloc::Static &&
1251 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1252 StringRef Sym(".destructors_used");
1253 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1259 if (GV->getName() == "llvm.tls_init_funcs") {
1260 EmitTLSInitFuncs(cast<ConstantArray>(GV->getInitializer()));
1267 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1268 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1269 /// is true, as being used with this directive.
1270 void AsmPrinter::EmitLLVMUsedList(const ConstantArray *InitList) {
1271 // Should be an array of 'i8*'.
1272 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1273 const GlobalValue *GV =
1274 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1275 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
1276 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip);
1280 typedef std::pair<unsigned, Constant*> Structor;
1282 static bool priority_order(const Structor& lhs, const Structor& rhs) {
1283 return lhs.first < rhs.first;
1286 /// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
1288 void AsmPrinter::EmitXXStructorList(const Constant *List, bool isCtor) {
1289 // Should be an array of '{ int, void ()* }' structs. The first value is the
1291 if (!isa<ConstantArray>(List)) return;
1293 // Sanity check the structors list.
1294 const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1295 if (!InitList) return; // Not an array!
1296 StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType());
1297 if (!ETy || ETy->getNumElements() != 2) return; // Not an array of pairs!
1298 if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) ||
1299 !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr).
1301 // Gather the structors in a form that's convenient for sorting by priority.
1302 SmallVector<Structor, 8> Structors;
1303 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1304 ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i));
1305 if (!CS) continue; // Malformed.
1306 if (CS->getOperand(1)->isNullValue())
1307 break; // Found a null terminator, skip the rest.
1308 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
1309 if (!Priority) continue; // Malformed.
1310 Structors.push_back(std::make_pair(Priority->getLimitedValue(65535),
1311 CS->getOperand(1)));
1314 // Emit the function pointers in the target-specific order
1315 const DataLayout *TD = TM.getDataLayout();
1316 unsigned Align = Log2_32(TD->getPointerPrefAlignment());
1317 std::stable_sort(Structors.begin(), Structors.end(), priority_order);
1318 for (unsigned i = 0, e = Structors.size(); i != e; ++i) {
1319 const MCSection *OutputSection =
1321 getObjFileLowering().getStaticCtorSection(Structors[i].first) :
1322 getObjFileLowering().getStaticDtorSection(Structors[i].first));
1323 OutStreamer.SwitchSection(OutputSection);
1324 if (OutStreamer.getCurrentSection() != OutStreamer.getPreviousSection())
1325 EmitAlignment(Align);
1326 EmitXXStructor(Structors[i].second);
1330 /// EmitTLSInitFuncs - Emit the TLS initialization functions.
1331 void AsmPrinter::EmitTLSInitFuncs(const ConstantArray *InitList) {
1332 const DataLayout *TD = TM.getDataLayout();
1333 OutStreamer.SwitchSection(getObjFileLowering().getTLSThreadInitSection());
1334 EmitAlignment(Log2_32(TD->getPointerPrefAlignment()));
1335 for (unsigned I = 0, E = InitList->getNumOperands(); I != E; ++I)
1337 dyn_cast<Constant>(InitList->getOperand(I)->stripPointerCasts()));
1340 //===--------------------------------------------------------------------===//
1341 // Emission and print routines
1344 /// EmitInt8 - Emit a byte directive and value.
1346 void AsmPrinter::EmitInt8(int Value) const {
1347 OutStreamer.EmitIntValue(Value, 1);
1350 /// EmitInt16 - Emit a short directive and value.
1352 void AsmPrinter::EmitInt16(int Value) const {
1353 OutStreamer.EmitIntValue(Value, 2);
1356 /// EmitInt32 - Emit a long directive and value.
1358 void AsmPrinter::EmitInt32(int Value) const {
1359 OutStreamer.EmitIntValue(Value, 4);
1362 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
1363 /// in bytes of the directive is specified by Size and Hi/Lo specify the
1364 /// labels. This implicitly uses .set if it is available.
1365 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1366 unsigned Size) const {
1367 // Get the Hi-Lo expression.
1368 const MCExpr *Diff =
1369 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1370 MCSymbolRefExpr::Create(Lo, OutContext),
1373 if (!MAI->hasSetDirective()) {
1374 OutStreamer.EmitValue(Diff, Size);
1378 // Otherwise, emit with .set (aka assignment).
1379 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1380 OutStreamer.EmitAssignment(SetLabel, Diff);
1381 OutStreamer.EmitSymbolValue(SetLabel, Size);
1384 /// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo"
1385 /// where the size in bytes of the directive is specified by Size and Hi/Lo
1386 /// specify the labels. This implicitly uses .set if it is available.
1387 void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset,
1388 const MCSymbol *Lo, unsigned Size)
1391 // Emit Hi+Offset - Lo
1392 // Get the Hi+Offset expression.
1393 const MCExpr *Plus =
1394 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext),
1395 MCConstantExpr::Create(Offset, OutContext),
1398 // Get the Hi+Offset-Lo expression.
1399 const MCExpr *Diff =
1400 MCBinaryExpr::CreateSub(Plus,
1401 MCSymbolRefExpr::Create(Lo, OutContext),
1404 if (!MAI->hasSetDirective())
1405 OutStreamer.EmitValue(Diff, 4);
1407 // Otherwise, emit with .set (aka assignment).
1408 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1409 OutStreamer.EmitAssignment(SetLabel, Diff);
1410 OutStreamer.EmitSymbolValue(SetLabel, 4);
1414 /// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
1415 /// where the size in bytes of the directive is specified by Size and Label
1416 /// specifies the label. This implicitly uses .set if it is available.
1417 void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset,
1421 // Emit Label+Offset (or just Label if Offset is zero)
1422 const MCExpr *Expr = MCSymbolRefExpr::Create(Label, OutContext);
1424 Expr = MCBinaryExpr::CreateAdd(Expr,
1425 MCConstantExpr::Create(Offset, OutContext),
1428 OutStreamer.EmitValue(Expr, Size);
1432 //===----------------------------------------------------------------------===//
1434 // EmitAlignment - Emit an alignment directive to the specified power of
1435 // two boundary. For example, if you pass in 3 here, you will get an 8
1436 // byte alignment. If a global value is specified, and if that global has
1437 // an explicit alignment requested, it will override the alignment request
1438 // if required for correctness.
1440 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV) const {
1441 if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getDataLayout(), NumBits);
1443 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.
1445 if (getCurrentSection()->getKind().isText())
1446 OutStreamer.EmitCodeAlignment(1 << NumBits);
1448 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
1451 //===----------------------------------------------------------------------===//
1452 // Constant emission.
1453 //===----------------------------------------------------------------------===//
1455 /// lowerConstant - Lower the specified LLVM Constant to an MCExpr.
1457 static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP) {
1458 MCContext &Ctx = AP.OutContext;
1460 if (CV->isNullValue() || isa<UndefValue>(CV))
1461 return MCConstantExpr::Create(0, Ctx);
1463 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1464 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1466 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1467 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx);
1469 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1470 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1472 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1474 llvm_unreachable("Unknown constant value to lower!");
1477 switch (CE->getOpcode()) {
1479 // If the code isn't optimized, there may be outstanding folding
1480 // opportunities. Attempt to fold the expression using DataLayout as a
1481 // last resort before giving up.
1483 ConstantFoldConstantExpression(CE, AP.TM.getDataLayout()))
1485 return lowerConstant(C, AP);
1487 // Otherwise report the problem to the user.
1490 raw_string_ostream OS(S);
1491 OS << "Unsupported expression in static initializer: ";
1492 WriteAsOperand(OS, CE, /*PrintType=*/false,
1493 !AP.MF ? 0 : AP.MF->getFunction()->getParent());
1494 report_fatal_error(OS.str());
1496 case Instruction::GetElementPtr: {
1497 const DataLayout &TD = *AP.TM.getDataLayout();
1498 // Generate a symbolic expression for the byte address
1499 APInt OffsetAI(TD.getPointerSizeInBits(), 0);
1500 cast<GEPOperator>(CE)->accumulateConstantOffset(TD, OffsetAI);
1502 const MCExpr *Base = lowerConstant(CE->getOperand(0), AP);
1506 int64_t Offset = OffsetAI.getSExtValue();
1507 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1511 case Instruction::Trunc:
1512 // We emit the value and depend on the assembler to truncate the generated
1513 // expression properly. This is important for differences between
1514 // blockaddress labels. Since the two labels are in the same function, it
1515 // is reasonable to treat their delta as a 32-bit value.
1517 case Instruction::BitCast:
1518 return lowerConstant(CE->getOperand(0), AP);
1520 case Instruction::IntToPtr: {
1521 const DataLayout &TD = *AP.TM.getDataLayout();
1522 // Handle casts to pointers by changing them into casts to the appropriate
1523 // integer type. This promotes constant folding and simplifies this code.
1524 Constant *Op = CE->getOperand(0);
1525 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
1527 return lowerConstant(Op, AP);
1530 case Instruction::PtrToInt: {
1531 const DataLayout &TD = *AP.TM.getDataLayout();
1532 // Support only foldable casts to/from pointers that can be eliminated by
1533 // changing the pointer to the appropriately sized integer type.
1534 Constant *Op = CE->getOperand(0);
1535 Type *Ty = CE->getType();
1537 const MCExpr *OpExpr = lowerConstant(Op, AP);
1539 // We can emit the pointer value into this slot if the slot is an
1540 // integer slot equal to the size of the pointer.
1541 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
1544 // Otherwise the pointer is smaller than the resultant integer, mask off
1545 // the high bits so we are sure to get a proper truncation if the input is
1547 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
1548 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1549 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1552 // The MC library also has a right-shift operator, but it isn't consistently
1553 // signed or unsigned between different targets.
1554 case Instruction::Add:
1555 case Instruction::Sub:
1556 case Instruction::Mul:
1557 case Instruction::SDiv:
1558 case Instruction::SRem:
1559 case Instruction::Shl:
1560 case Instruction::And:
1561 case Instruction::Or:
1562 case Instruction::Xor: {
1563 const MCExpr *LHS = lowerConstant(CE->getOperand(0), AP);
1564 const MCExpr *RHS = lowerConstant(CE->getOperand(1), AP);
1565 switch (CE->getOpcode()) {
1566 default: llvm_unreachable("Unknown binary operator constant cast expr");
1567 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1568 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1569 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1570 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1571 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1572 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1573 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1574 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1575 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1581 static void emitGlobalConstantImpl(const Constant *C, unsigned AddrSpace,
1584 /// isRepeatedByteSequence - Determine whether the given value is
1585 /// composed of a repeated sequence of identical bytes and return the
1586 /// byte value. If it is not a repeated sequence, return -1.
1587 static int isRepeatedByteSequence(const ConstantDataSequential *V) {
1588 StringRef Data = V->getRawDataValues();
1589 assert(!Data.empty() && "Empty aggregates should be CAZ node");
1591 for (unsigned i = 1, e = Data.size(); i != e; ++i)
1592 if (Data[i] != C) return -1;
1593 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1.
1597 /// isRepeatedByteSequence - Determine whether the given value is
1598 /// composed of a repeated sequence of identical bytes and return the
1599 /// byte value. If it is not a repeated sequence, return -1.
1600 static int isRepeatedByteSequence(const Value *V, TargetMachine &TM) {
1602 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
1603 if (CI->getBitWidth() > 64) return -1;
1605 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(V->getType());
1606 uint64_t Value = CI->getZExtValue();
1608 // Make sure the constant is at least 8 bits long and has a power
1609 // of 2 bit width. This guarantees the constant bit width is
1610 // always a multiple of 8 bits, avoiding issues with padding out
1611 // to Size and other such corner cases.
1612 if (CI->getBitWidth() < 8 || !isPowerOf2_64(CI->getBitWidth())) return -1;
1614 uint8_t Byte = static_cast<uint8_t>(Value);
1616 for (unsigned i = 1; i < Size; ++i) {
1618 if (static_cast<uint8_t>(Value) != Byte) return -1;
1622 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) {
1623 // Make sure all array elements are sequences of the same repeated
1625 assert(CA->getNumOperands() != 0 && "Should be a CAZ");
1626 int Byte = isRepeatedByteSequence(CA->getOperand(0), TM);
1627 if (Byte == -1) return -1;
1629 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i) {
1630 int ThisByte = isRepeatedByteSequence(CA->getOperand(i), TM);
1631 if (ThisByte == -1) return -1;
1632 if (Byte != ThisByte) return -1;
1637 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V))
1638 return isRepeatedByteSequence(CDS);
1643 static void emitGlobalConstantDataSequential(const ConstantDataSequential *CDS,
1644 unsigned AddrSpace,AsmPrinter &AP){
1646 // See if we can aggregate this into a .fill, if so, emit it as such.
1647 int Value = isRepeatedByteSequence(CDS, AP.TM);
1649 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CDS->getType());
1650 // Don't emit a 1-byte object as a .fill.
1652 return AP.OutStreamer.EmitFill(Bytes, Value, AddrSpace);
1655 // If this can be emitted with .ascii/.asciz, emit it as such.
1656 if (CDS->isString())
1657 return AP.OutStreamer.EmitBytes(CDS->getAsString(), AddrSpace);
1659 // Otherwise, emit the values in successive locations.
1660 unsigned ElementByteSize = CDS->getElementByteSize();
1661 if (isa<IntegerType>(CDS->getElementType())) {
1662 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1664 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1665 CDS->getElementAsInteger(i));
1666 AP.OutStreamer.EmitIntValue(CDS->getElementAsInteger(i),
1667 ElementByteSize, AddrSpace);
1669 } else if (ElementByteSize == 4) {
1670 // FP Constants are printed as integer constants to avoid losing
1672 assert(CDS->getElementType()->isFloatTy());
1673 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1679 F = CDS->getElementAsFloat(i);
1681 AP.OutStreamer.GetCommentOS() << "float " << F << '\n';
1682 AP.OutStreamer.EmitIntValue(I, 4, AddrSpace);
1685 assert(CDS->getElementType()->isDoubleTy());
1686 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1692 F = CDS->getElementAsDouble(i);
1694 AP.OutStreamer.GetCommentOS() << "double " << F << '\n';
1695 AP.OutStreamer.EmitIntValue(I, 8, AddrSpace);
1699 const DataLayout &TD = *AP.TM.getDataLayout();
1700 unsigned Size = TD.getTypeAllocSize(CDS->getType());
1701 unsigned EmittedSize = TD.getTypeAllocSize(CDS->getType()->getElementType()) *
1702 CDS->getNumElements();
1703 if (unsigned Padding = Size - EmittedSize)
1704 AP.OutStreamer.EmitZeros(Padding, AddrSpace);
1708 static void emitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
1710 // See if we can aggregate some values. Make sure it can be
1711 // represented as a series of bytes of the constant value.
1712 int Value = isRepeatedByteSequence(CA, AP.TM);
1715 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CA->getType());
1716 AP.OutStreamer.EmitFill(Bytes, Value, AddrSpace);
1719 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1720 emitGlobalConstantImpl(CA->getOperand(i), AddrSpace, AP);
1724 static void emitGlobalConstantVector(const ConstantVector *CV,
1725 unsigned AddrSpace, AsmPrinter &AP) {
1726 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1727 emitGlobalConstantImpl(CV->getOperand(i), AddrSpace, AP);
1729 const DataLayout &TD = *AP.TM.getDataLayout();
1730 unsigned Size = TD.getTypeAllocSize(CV->getType());
1731 unsigned EmittedSize = TD.getTypeAllocSize(CV->getType()->getElementType()) *
1732 CV->getType()->getNumElements();
1733 if (unsigned Padding = Size - EmittedSize)
1734 AP.OutStreamer.EmitZeros(Padding, AddrSpace);
1737 static void emitGlobalConstantStruct(const ConstantStruct *CS,
1738 unsigned AddrSpace, AsmPrinter &AP) {
1739 // Print the fields in successive locations. Pad to align if needed!
1740 const DataLayout *TD = AP.TM.getDataLayout();
1741 unsigned Size = TD->getTypeAllocSize(CS->getType());
1742 const StructLayout *Layout = TD->getStructLayout(CS->getType());
1743 uint64_t SizeSoFar = 0;
1744 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1745 const Constant *Field = CS->getOperand(i);
1747 // Check if padding is needed and insert one or more 0s.
1748 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
1749 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1750 - Layout->getElementOffset(i)) - FieldSize;
1751 SizeSoFar += FieldSize + PadSize;
1753 // Now print the actual field value.
1754 emitGlobalConstantImpl(Field, AddrSpace, AP);
1756 // Insert padding - this may include padding to increase the size of the
1757 // current field up to the ABI size (if the struct is not packed) as well
1758 // as padding to ensure that the next field starts at the right offset.
1759 AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
1761 assert(SizeSoFar == Layout->getSizeInBytes() &&
1762 "Layout of constant struct may be incorrect!");
1765 static void emitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
1767 APInt API = CFP->getValueAPF().bitcastToAPInt();
1769 // First print a comment with what we think the original floating-point value
1770 // should have been.
1771 if (AP.isVerbose()) {
1772 SmallString<8> StrVal;
1773 CFP->getValueAPF().toString(StrVal);
1775 CFP->getType()->print(AP.OutStreamer.GetCommentOS());
1776 AP.OutStreamer.GetCommentOS() << ' ' << StrVal << '\n';
1779 // Now iterate through the APInt chunks, emitting them in endian-correct
1780 // order, possibly with a smaller chunk at beginning/end (e.g. for x87 80-bit
1782 unsigned NumBytes = API.getBitWidth() / 8;
1783 unsigned TrailingBytes = NumBytes % sizeof(uint64_t);
1784 const uint64_t *p = API.getRawData();
1786 // PPC's long double has odd notions of endianness compared to how LLVM
1787 // handles it: p[0] goes first for *big* endian on PPC.
1788 if (AP.TM.getDataLayout()->isBigEndian() != CFP->getType()->isPPC_FP128Ty()) {
1789 int Chunk = API.getNumWords() - 1;
1792 AP.OutStreamer.EmitIntValue(p[Chunk--], TrailingBytes, AddrSpace);
1794 for (; Chunk >= 0; --Chunk)
1795 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t), AddrSpace);
1798 for (Chunk = 0; Chunk < NumBytes / sizeof(uint64_t); ++Chunk)
1799 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t), AddrSpace);
1802 AP.OutStreamer.EmitIntValue(p[Chunk], TrailingBytes, AddrSpace);
1805 // Emit the tail padding for the long double.
1806 const DataLayout &TD = *AP.TM.getDataLayout();
1807 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
1808 TD.getTypeStoreSize(CFP->getType()), AddrSpace);
1811 static void emitGlobalConstantLargeInt(const ConstantInt *CI,
1812 unsigned AddrSpace, AsmPrinter &AP) {
1813 const DataLayout *TD = AP.TM.getDataLayout();
1814 unsigned BitWidth = CI->getBitWidth();
1815 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
1817 // We don't expect assemblers to support integer data directives
1818 // for more than 64 bits, so we emit the data in at most 64-bit
1819 // quantities at a time.
1820 const uint64_t *RawData = CI->getValue().getRawData();
1821 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1822 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1823 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1827 static void emitGlobalConstantImpl(const Constant *CV, unsigned AddrSpace,
1829 const DataLayout *TD = AP.TM.getDataLayout();
1830 uint64_t Size = TD->getTypeAllocSize(CV->getType());
1831 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV))
1832 return AP.OutStreamer.EmitZeros(Size, AddrSpace);
1834 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1841 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1842 CI->getZExtValue());
1843 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1846 emitGlobalConstantLargeInt(CI, AddrSpace, AP);
1851 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1852 return emitGlobalConstantFP(CFP, AddrSpace, AP);
1854 if (isa<ConstantPointerNull>(CV)) {
1855 AP.OutStreamer.EmitIntValue(0, Size, AddrSpace);
1859 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV))
1860 return emitGlobalConstantDataSequential(CDS, AddrSpace, AP);
1862 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1863 return emitGlobalConstantArray(CVA, AddrSpace, AP);
1865 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1866 return emitGlobalConstantStruct(CVS, AddrSpace, AP);
1868 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
1869 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
1871 if (CE->getOpcode() == Instruction::BitCast)
1872 return emitGlobalConstantImpl(CE->getOperand(0), AddrSpace, AP);
1875 // If the constant expression's size is greater than 64-bits, then we have
1876 // to emit the value in chunks. Try to constant fold the value and emit it
1878 Constant *New = ConstantFoldConstantExpression(CE, TD);
1879 if (New && New != CE)
1880 return emitGlobalConstantImpl(New, AddrSpace, AP);
1884 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1885 return emitGlobalConstantVector(V, AddrSpace, AP);
1887 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1888 // thread the streamer with EmitValue.
1889 AP.OutStreamer.EmitValue(lowerConstant(CV, AP), Size, AddrSpace);
1892 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1893 void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1894 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(CV->getType());
1896 emitGlobalConstantImpl(CV, AddrSpace, *this);
1897 else if (MAI->hasSubsectionsViaSymbols()) {
1898 // If the global has zero size, emit a single byte so that two labels don't
1899 // look like they are at the same location.
1900 OutStreamer.EmitIntValue(0, 1, AddrSpace);
1904 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1905 // Target doesn't support this yet!
1906 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1909 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1911 OS << '+' << Offset;
1912 else if (Offset < 0)
1916 //===----------------------------------------------------------------------===//
1917 // Symbol Lowering Routines.
1918 //===----------------------------------------------------------------------===//
1920 /// GetTempSymbol - Return the MCSymbol corresponding to the assembler
1921 /// temporary label with the specified stem and unique ID.
1922 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const {
1923 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) +
1927 /// GetTempSymbol - Return an assembler temporary label with the specified
1929 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const {
1930 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix())+
1935 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
1936 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
1939 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
1940 return MMI->getAddrLabelSymbol(BB);
1943 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1944 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1945 return OutContext.GetOrCreateSymbol
1946 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
1947 + "_" + Twine(CPID));
1950 /// GetJTISymbol - Return the symbol for the specified jump table entry.
1951 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1952 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
1955 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
1956 /// FIXME: privatize to AsmPrinter.
1957 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
1958 return OutContext.GetOrCreateSymbol
1959 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
1960 Twine(UID) + "_set_" + Twine(MBBID));
1963 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1964 /// global value name as its base, with the specified suffix, and where the
1965 /// symbol is forced to have private linkage if ForcePrivate is true.
1966 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1968 bool ForcePrivate) const {
1969 SmallString<60> NameStr;
1970 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1971 NameStr.append(Suffix.begin(), Suffix.end());
1972 return OutContext.GetOrCreateSymbol(NameStr.str());
1975 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
1977 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
1978 SmallString<60> NameStr;
1979 Mang->getNameWithPrefix(NameStr, Sym);
1980 return OutContext.GetOrCreateSymbol(NameStr.str());
1985 /// PrintParentLoopComment - Print comments about parent loops of this one.
1986 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1987 unsigned FunctionNumber) {
1988 if (Loop == 0) return;
1989 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
1990 OS.indent(Loop->getLoopDepth()*2)
1991 << "Parent Loop BB" << FunctionNumber << "_"
1992 << Loop->getHeader()->getNumber()
1993 << " Depth=" << Loop->getLoopDepth() << '\n';
1997 /// PrintChildLoopComment - Print comments about child loops within
1998 /// the loop for this basic block, with nesting.
1999 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2000 unsigned FunctionNumber) {
2001 // Add child loop information
2002 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
2003 OS.indent((*CL)->getLoopDepth()*2)
2004 << "Child Loop BB" << FunctionNumber << "_"
2005 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
2007 PrintChildLoopComment(OS, *CL, FunctionNumber);
2011 /// emitBasicBlockLoopComments - Pretty-print comments for basic blocks.
2012 static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
2013 const MachineLoopInfo *LI,
2014 const AsmPrinter &AP) {
2015 // Add loop depth information
2016 const MachineLoop *Loop = LI->getLoopFor(&MBB);
2017 if (Loop == 0) return;
2019 MachineBasicBlock *Header = Loop->getHeader();
2020 assert(Header && "No header for loop");
2022 // If this block is not a loop header, just print out what is the loop header
2024 if (Header != &MBB) {
2025 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
2026 Twine(AP.getFunctionNumber())+"_" +
2027 Twine(Loop->getHeader()->getNumber())+
2028 " Depth="+Twine(Loop->getLoopDepth()));
2032 // Otherwise, it is a loop header. Print out information about child and
2034 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
2036 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
2039 OS.indent(Loop->getLoopDepth()*2-2);
2044 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
2046 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
2050 /// EmitBasicBlockStart - This method prints the label for the specified
2051 /// MachineBasicBlock, an alignment (if present) and a comment describing
2052 /// it if appropriate.
2053 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
2054 // Emit an alignment directive for this block, if needed.
2055 if (unsigned Align = MBB->getAlignment())
2056 EmitAlignment(Align);
2058 // If the block has its address taken, emit any labels that were used to
2059 // reference the block. It is possible that there is more than one label
2060 // here, because multiple LLVM BB's may have been RAUW'd to this block after
2061 // the references were generated.
2062 if (MBB->hasAddressTaken()) {
2063 const BasicBlock *BB = MBB->getBasicBlock();
2065 OutStreamer.AddComment("Block address taken");
2067 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
2069 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
2070 OutStreamer.EmitLabel(Syms[i]);
2073 // Print some verbose block comments.
2075 if (const BasicBlock *BB = MBB->getBasicBlock())
2077 OutStreamer.AddComment("%" + BB->getName());
2078 emitBasicBlockLoopComments(*MBB, LI, *this);
2081 // Print the main label for the block.
2082 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
2083 if (isVerbose() && OutStreamer.hasRawTextSupport()) {
2084 // NOTE: Want this comment at start of line, don't emit with AddComment.
2085 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" +
2086 Twine(MBB->getNumber()) + ":");
2089 OutStreamer.EmitLabel(MBB->getSymbol());
2093 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility,
2094 bool IsDefinition) const {
2095 MCSymbolAttr Attr = MCSA_Invalid;
2097 switch (Visibility) {
2099 case GlobalValue::HiddenVisibility:
2101 Attr = MAI->getHiddenVisibilityAttr();
2103 Attr = MAI->getHiddenDeclarationVisibilityAttr();
2105 case GlobalValue::ProtectedVisibility:
2106 Attr = MAI->getProtectedVisibilityAttr();
2110 if (Attr != MCSA_Invalid)
2111 OutStreamer.EmitSymbolAttribute(Sym, Attr);
2114 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
2115 /// exactly one predecessor and the control transfer mechanism between
2116 /// the predecessor and this block is a fall-through.
2118 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
2119 // If this is a landing pad, it isn't a fall through. If it has no preds,
2120 // then nothing falls through to it.
2121 if (MBB->isLandingPad() || MBB->pred_empty())
2124 // If there isn't exactly one predecessor, it can't be a fall through.
2125 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
2127 if (PI2 != MBB->pred_end())
2130 // The predecessor has to be immediately before this block.
2131 MachineBasicBlock *Pred = *PI;
2133 if (!Pred->isLayoutSuccessor(MBB))
2136 // If the block is completely empty, then it definitely does fall through.
2140 // Check the terminators in the previous blocks
2141 for (MachineBasicBlock::iterator II = Pred->getFirstTerminator(),
2142 IE = Pred->end(); II != IE; ++II) {
2143 MachineInstr &MI = *II;
2145 // If it is not a simple branch, we are in a table somewhere.
2146 if (!MI.isBranch() || MI.isIndirectBranch())
2149 // If we are the operands of one of the branches, this is not
2151 for (MachineInstr::mop_iterator OI = MI.operands_begin(),
2152 OE = MI.operands_end(); OI != OE; ++OI) {
2153 const MachineOperand& OP = *OI;
2156 if (OP.isMBB() && OP.getMBB() == MBB)
2166 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
2167 if (!S->usesMetadata())
2170 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
2171 gcp_map_type::iterator GCPI = GCMap.find(S);
2172 if (GCPI != GCMap.end())
2173 return GCPI->second;
2175 const char *Name = S->getName().c_str();
2177 for (GCMetadataPrinterRegistry::iterator
2178 I = GCMetadataPrinterRegistry::begin(),
2179 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
2180 if (strcmp(Name, I->getName()) == 0) {
2181 GCMetadataPrinter *GMP = I->instantiate();
2183 GCMap.insert(std::make_pair(S, GMP));
2187 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));