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);
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 StringRef Name = DISubprogram(V.getContext()).getDisplayName();
570 OS << V.getName() << " <- ";
572 // Register or immediate value. Register 0 means undef.
573 if (MI->getOperand(0).isFPImm()) {
574 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
575 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
576 OS << (double)APF.convertToFloat();
577 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
578 OS << APF.convertToDouble();
580 // There is no good way to print long double. Convert a copy to
581 // double. Ah well, it's only a comment.
583 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
585 OS << "(long double) " << APF.convertToDouble();
587 } else if (MI->getOperand(0).isImm()) {
588 OS << MI->getOperand(0).getImm();
589 } else if (MI->getOperand(0).isCImm()) {
590 MI->getOperand(0).getCImm()->getValue().print(OS, false /*isSigned*/);
592 assert(MI->getOperand(0).isReg() && "Unknown operand type");
593 if (MI->getOperand(0).getReg() == 0) {
594 // Suppress offset, it is not meaningful here.
596 // NOTE: Want this comment at start of line, don't emit with AddComment.
597 AP.OutStreamer.EmitRawText(OS.str());
600 OS << AP.TM.getRegisterInfo()->getName(MI->getOperand(0).getReg());
603 OS << '+' << MI->getOperand(1).getImm();
604 // NOTE: Want this comment at start of line, don't emit with AddComment.
605 AP.OutStreamer.EmitRawText(OS.str());
609 AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() {
610 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI &&
611 MF->getFunction()->needsUnwindTableEntry())
614 if (MMI->hasDebugInfo())
620 bool AsmPrinter::needsSEHMoves() {
621 return MAI->getExceptionHandlingType() == ExceptionHandling::Win64 &&
622 MF->getFunction()->needsUnwindTableEntry();
625 bool AsmPrinter::needsRelocationsForDwarfStringPool() const {
626 return MAI->doesDwarfUseRelocationsAcrossSections();
629 void AsmPrinter::emitPrologLabel(const MachineInstr &MI) {
630 MCSymbol *Label = MI.getOperand(0).getMCSymbol();
632 if (MAI->getExceptionHandlingType() != ExceptionHandling::DwarfCFI)
635 if (needsCFIMoves() == CFI_M_None)
638 if (MMI->getCompactUnwindEncoding() != 0)
639 OutStreamer.EmitCompactUnwindEncoding(MMI->getCompactUnwindEncoding());
641 MachineModuleInfo &MMI = MF->getMMI();
642 std::vector<MCCFIInstruction> Instructions = MMI.getFrameInstructions();
643 bool FoundOne = false;
645 for (std::vector<MCCFIInstruction>::iterator I = Instructions.begin(),
646 E = Instructions.end(); I != E; ++I) {
647 if (I->getLabel() == Label) {
648 emitCFIInstruction(*I);
655 /// EmitFunctionBody - This method emits the body and trailer for a
657 void AsmPrinter::EmitFunctionBody() {
658 // Emit target-specific gunk before the function body.
659 EmitFunctionBodyStart();
661 bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo();
663 // Print out code for the function.
664 bool HasAnyRealCode = false;
665 const MachineInstr *LastMI = 0;
666 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
668 // Print a label for the basic block.
669 EmitBasicBlockStart(I);
670 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
674 // Print the assembly for the instruction.
675 if (!II->isLabel() && !II->isImplicitDef() && !II->isKill() &&
676 !II->isDebugValue()) {
677 HasAnyRealCode = true;
681 if (ShouldPrintDebugScopes) {
682 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
683 DD->beginInstruction(II);
687 emitComments(*II, OutStreamer.GetCommentOS());
689 switch (II->getOpcode()) {
690 case TargetOpcode::PROLOG_LABEL:
691 emitPrologLabel(*II);
694 case TargetOpcode::EH_LABEL:
695 case TargetOpcode::GC_LABEL:
696 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol());
698 case TargetOpcode::INLINEASM:
701 case TargetOpcode::DBG_VALUE:
703 if (!emitDebugValueComment(II, *this))
707 case TargetOpcode::IMPLICIT_DEF:
708 if (isVerbose()) emitImplicitDef(II, *this);
710 case TargetOpcode::KILL:
711 if (isVerbose()) emitKill(II, *this);
714 if (!TM.hasMCUseLoc())
715 MCLineEntry::Make(&OutStreamer, getCurrentSection());
721 if (ShouldPrintDebugScopes) {
722 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
723 DD->endInstruction(II);
728 // If the last instruction was a prolog label, then we have a situation where
729 // we emitted a prolog but no function body. This results in the ending prolog
730 // label equaling the end of function label and an invalid "row" in the
731 // FDE. We need to emit a noop in this situation so that the FDE's rows are
733 bool RequiresNoop = LastMI && LastMI->isPrologLabel();
735 // If the function is empty and the object file uses .subsections_via_symbols,
736 // then we need to emit *something* to the function body to prevent the
737 // labels from collapsing together. Just emit a noop.
738 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) || RequiresNoop) {
740 TM.getInstrInfo()->getNoopForMachoTarget(Noop);
741 if (Noop.getOpcode()) {
742 OutStreamer.AddComment("avoids zero-length function");
743 OutStreamer.EmitInstruction(Noop);
744 } else // Target not mc-ized yet.
745 OutStreamer.EmitRawText(StringRef("\tnop\n"));
748 const Function *F = MF->getFunction();
749 for (Function::const_iterator i = F->begin(), e = F->end(); i != e; ++i) {
750 const BasicBlock *BB = i;
751 if (!BB->hasAddressTaken())
753 MCSymbol *Sym = GetBlockAddressSymbol(BB);
754 if (Sym->isDefined())
756 OutStreamer.AddComment("Address of block that was removed by CodeGen");
757 OutStreamer.EmitLabel(Sym);
760 // Emit target-specific gunk after the function body.
761 EmitFunctionBodyEnd();
763 // If the target wants a .size directive for the size of the function, emit
765 if (MAI->hasDotTypeDotSizeDirective()) {
766 // Create a symbol for the end of function, so we can get the size as
767 // difference between the function label and the temp label.
768 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
769 OutStreamer.EmitLabel(FnEndLabel);
771 const MCExpr *SizeExp =
772 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
773 MCSymbolRefExpr::Create(CurrentFnSymForSize,
776 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
779 // Emit post-function debug information.
781 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
785 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled);
790 // Print out jump tables referenced by the function.
793 OutStreamer.AddBlankLine();
796 /// getDebugValueLocation - Get location information encoded by DBG_VALUE
798 MachineLocation AsmPrinter::
799 getDebugValueLocation(const MachineInstr *MI) const {
800 // Target specific DBG_VALUE instructions are handled by each target.
801 return MachineLocation();
804 /// EmitDwarfRegOp - Emit dwarf register operation.
805 void AsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc) const {
806 const TargetRegisterInfo *TRI = TM.getRegisterInfo();
807 int Reg = TRI->getDwarfRegNum(MLoc.getReg(), false);
809 for (MCSuperRegIterator SR(MLoc.getReg(), TRI); SR.isValid() && Reg < 0;
811 Reg = TRI->getDwarfRegNum(*SR, false);
812 // FIXME: Get the bit range this register uses of the superregister
813 // so that we can produce a DW_OP_bit_piece
816 // FIXME: Handle cases like a super register being encoded as
817 // DW_OP_reg 32 DW_OP_piece 4 DW_OP_reg 33
819 // FIXME: We have no reasonable way of handling errors in here. The
820 // caller might be in the middle of an dwarf expression. We should
821 // probably assert that Reg >= 0 once debug info generation is more mature.
823 if (MLoc.isIndirect()) {
825 OutStreamer.AddComment(
826 dwarf::OperationEncodingString(dwarf::DW_OP_breg0 + Reg));
827 EmitInt8(dwarf::DW_OP_breg0 + Reg);
829 OutStreamer.AddComment("DW_OP_bregx");
830 EmitInt8(dwarf::DW_OP_bregx);
831 OutStreamer.AddComment(Twine(Reg));
834 EmitSLEB128(MLoc.getOffset());
837 OutStreamer.AddComment(
838 dwarf::OperationEncodingString(dwarf::DW_OP_reg0 + Reg));
839 EmitInt8(dwarf::DW_OP_reg0 + Reg);
841 OutStreamer.AddComment("DW_OP_regx");
842 EmitInt8(dwarf::DW_OP_regx);
843 OutStreamer.AddComment(Twine(Reg));
848 // FIXME: Produce a DW_OP_bit_piece if we used a superregister
851 bool AsmPrinter::doFinalization(Module &M) {
852 // Emit global variables.
853 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
855 EmitGlobalVariable(I);
857 // Emit visibility info for declarations
858 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
859 const Function &F = *I;
860 if (!F.isDeclaration())
862 GlobalValue::VisibilityTypes V = F.getVisibility();
863 if (V == GlobalValue::DefaultVisibility)
866 MCSymbol *Name = Mang->getSymbol(&F);
867 EmitVisibility(Name, V, false);
870 // Emit module flags.
871 SmallVector<Module::ModuleFlagEntry, 8> ModuleFlags;
872 M.getModuleFlagsMetadata(ModuleFlags);
873 if (!ModuleFlags.empty())
874 getObjFileLowering().emitModuleFlags(OutStreamer, ModuleFlags, Mang, TM);
876 // Finalize debug and EH information.
879 NamedRegionTimer T(EHTimerName, DWARFGroupName, TimePassesIsEnabled);
886 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
892 // If the target wants to know about weak references, print them all.
893 if (MAI->getWeakRefDirective()) {
894 // FIXME: This is not lazy, it would be nice to only print weak references
895 // to stuff that is actually used. Note that doing so would require targets
896 // to notice uses in operands (due to constant exprs etc). This should
897 // happen with the MC stuff eventually.
899 // Print out module-level global variables here.
900 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
902 if (!I->hasExternalWeakLinkage()) continue;
903 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
906 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
907 if (!I->hasExternalWeakLinkage()) continue;
908 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
912 if (MAI->hasSetDirective()) {
913 OutStreamer.AddBlankLine();
914 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
916 MCSymbol *Name = Mang->getSymbol(I);
918 const GlobalValue *GV = I->getAliasedGlobal();
919 MCSymbol *Target = Mang->getSymbol(GV);
921 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
922 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
923 else if (I->hasWeakLinkage())
924 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
926 assert(I->hasLocalLinkage() && "Invalid alias linkage");
928 EmitVisibility(Name, I->getVisibility());
930 // Emit the directives as assignments aka .set:
931 OutStreamer.EmitAssignment(Name,
932 MCSymbolRefExpr::Create(Target, OutContext));
936 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
937 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
938 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
939 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
940 MP->finishAssembly(*this);
942 // If we don't have any trampolines, then we don't require stack memory
943 // to be executable. Some targets have a directive to declare this.
944 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
945 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
946 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext))
947 OutStreamer.SwitchSection(S);
949 // Allow the target to emit any magic that it wants at the end of the file,
950 // after everything else has gone out.
953 delete Mang; Mang = 0;
956 OutStreamer.Finish();
962 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
964 // Get the function symbol.
965 CurrentFnSym = Mang->getSymbol(MF.getFunction());
966 CurrentFnSymForSize = CurrentFnSym;
969 LI = &getAnalysis<MachineLoopInfo>();
973 // SectionCPs - Keep track the alignment, constpool entries per Section.
977 SmallVector<unsigned, 4> CPEs;
978 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
982 /// EmitConstantPool - Print to the current output stream assembly
983 /// representations of the constants in the constant pool MCP. This is
984 /// used to print out constants which have been "spilled to memory" by
985 /// the code generator.
987 void AsmPrinter::EmitConstantPool() {
988 const MachineConstantPool *MCP = MF->getConstantPool();
989 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
990 if (CP.empty()) return;
992 // Calculate sections for constant pool entries. We collect entries to go into
993 // the same section together to reduce amount of section switch statements.
994 SmallVector<SectionCPs, 4> CPSections;
995 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
996 const MachineConstantPoolEntry &CPE = CP[i];
997 unsigned Align = CPE.getAlignment();
1000 switch (CPE.getRelocationInfo()) {
1001 default: llvm_unreachable("Unknown section kind");
1002 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
1004 Kind = SectionKind::getReadOnlyWithRelLocal();
1007 switch (TM.getDataLayout()->getTypeAllocSize(CPE.getType())) {
1008 case 4: Kind = SectionKind::getMergeableConst4(); break;
1009 case 8: Kind = SectionKind::getMergeableConst8(); break;
1010 case 16: Kind = SectionKind::getMergeableConst16();break;
1011 default: Kind = SectionKind::getMergeableConst(); break;
1015 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
1017 // The number of sections are small, just do a linear search from the
1018 // last section to the first.
1020 unsigned SecIdx = CPSections.size();
1021 while (SecIdx != 0) {
1022 if (CPSections[--SecIdx].S == S) {
1028 SecIdx = CPSections.size();
1029 CPSections.push_back(SectionCPs(S, Align));
1032 if (Align > CPSections[SecIdx].Alignment)
1033 CPSections[SecIdx].Alignment = Align;
1034 CPSections[SecIdx].CPEs.push_back(i);
1037 // Now print stuff into the calculated sections.
1038 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
1039 OutStreamer.SwitchSection(CPSections[i].S);
1040 EmitAlignment(Log2_32(CPSections[i].Alignment));
1042 unsigned Offset = 0;
1043 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
1044 unsigned CPI = CPSections[i].CPEs[j];
1045 MachineConstantPoolEntry CPE = CP[CPI];
1047 // Emit inter-object padding for alignment.
1048 unsigned AlignMask = CPE.getAlignment() - 1;
1049 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
1050 OutStreamer.EmitZeros(NewOffset - Offset);
1052 Type *Ty = CPE.getType();
1053 Offset = NewOffset + TM.getDataLayout()->getTypeAllocSize(Ty);
1054 OutStreamer.EmitLabel(GetCPISymbol(CPI));
1056 if (CPE.isMachineConstantPoolEntry())
1057 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
1059 EmitGlobalConstant(CPE.Val.ConstVal);
1064 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
1065 /// by the current function to the current output stream.
1067 void AsmPrinter::EmitJumpTableInfo() {
1068 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1069 if (MJTI == 0) return;
1070 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
1071 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1072 if (JT.empty()) return;
1074 // Pick the directive to use to print the jump table entries, and switch to
1075 // the appropriate section.
1076 const Function *F = MF->getFunction();
1077 bool JTInDiffSection = false;
1078 if (// In PIC mode, we need to emit the jump table to the same section as the
1079 // function body itself, otherwise the label differences won't make sense.
1080 // FIXME: Need a better predicate for this: what about custom entries?
1081 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
1082 // We should also do if the section name is NULL or function is declared
1083 // in discardable section
1084 // FIXME: this isn't the right predicate, should be based on the MCSection
1085 // for the function.
1086 F->isWeakForLinker()) {
1087 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
1089 // Otherwise, drop it in the readonly section.
1090 const MCSection *ReadOnlySection =
1091 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
1092 OutStreamer.SwitchSection(ReadOnlySection);
1093 JTInDiffSection = true;
1096 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getDataLayout())));
1098 // Jump tables in code sections are marked with a data_region directive
1099 // where that's supported.
1100 if (!JTInDiffSection)
1101 OutStreamer.EmitDataRegion(MCDR_DataRegionJT32);
1103 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
1104 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1106 // If this jump table was deleted, ignore it.
1107 if (JTBBs.empty()) continue;
1109 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
1110 // .set directive for each unique entry. This reduces the number of
1111 // relocations the assembler will generate for the jump table.
1112 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
1113 MAI->hasSetDirective()) {
1114 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
1115 const TargetLowering *TLI = TM.getTargetLowering();
1116 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
1117 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
1118 const MachineBasicBlock *MBB = JTBBs[ii];
1119 if (!EmittedSets.insert(MBB)) continue;
1121 // .set LJTSet, LBB32-base
1123 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1124 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
1125 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
1129 // On some targets (e.g. Darwin) we want to emit two consecutive labels
1130 // before each jump table. The first label is never referenced, but tells
1131 // the assembler and linker the extents of the jump table object. The
1132 // second label is actually referenced by the code.
1133 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
1134 // FIXME: This doesn't have to have any specific name, just any randomly
1135 // named and numbered 'l' label would work. Simplify GetJTISymbol.
1136 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
1138 OutStreamer.EmitLabel(GetJTISymbol(JTI));
1140 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
1141 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
1143 if (!JTInDiffSection)
1144 OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
1147 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
1149 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
1150 const MachineBasicBlock *MBB,
1151 unsigned UID) const {
1152 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block");
1153 const MCExpr *Value = 0;
1154 switch (MJTI->getEntryKind()) {
1155 case MachineJumpTableInfo::EK_Inline:
1156 llvm_unreachable("Cannot emit EK_Inline jump table entry");
1157 case MachineJumpTableInfo::EK_Custom32:
1158 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
1161 case MachineJumpTableInfo::EK_BlockAddress:
1162 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
1164 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1166 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
1167 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
1168 // with a relocation as gp-relative, e.g.:
1170 MCSymbol *MBBSym = MBB->getSymbol();
1171 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1175 case MachineJumpTableInfo::EK_GPRel64BlockAddress: {
1176 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded
1177 // with a relocation as gp-relative, e.g.:
1179 MCSymbol *MBBSym = MBB->getSymbol();
1180 OutStreamer.EmitGPRel64Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1184 case MachineJumpTableInfo::EK_LabelDifference32: {
1185 // EK_LabelDifference32 - Each entry is the address of the block minus
1186 // the address of the jump table. This is used for PIC jump tables where
1187 // gprel32 is not supported. e.g.:
1188 // .word LBB123 - LJTI1_2
1189 // If the .set directive is supported, this is emitted as:
1190 // .set L4_5_set_123, LBB123 - LJTI1_2
1191 // .word L4_5_set_123
1193 // If we have emitted set directives for the jump table entries, print
1194 // them rather than the entries themselves. If we're emitting PIC, then
1195 // emit the table entries as differences between two text section labels.
1196 if (MAI->hasSetDirective()) {
1197 // If we used .set, reference the .set's symbol.
1198 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
1202 // Otherwise, use the difference as the jump table entry.
1203 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1204 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
1205 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
1210 assert(Value && "Unknown entry kind!");
1212 unsigned EntrySize = MJTI->getEntrySize(*TM.getDataLayout());
1213 OutStreamer.EmitValue(Value, EntrySize);
1217 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
1218 /// special global used by LLVM. If so, emit it and return true, otherwise
1219 /// do nothing and return false.
1220 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
1221 if (GV->getName() == "llvm.used") {
1222 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
1223 EmitLLVMUsedList(cast<ConstantArray>(GV->getInitializer()));
1227 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
1228 if (GV->getSection() == "llvm.metadata" ||
1229 GV->hasAvailableExternallyLinkage())
1232 if (!GV->hasAppendingLinkage()) return false;
1234 assert(GV->hasInitializer() && "Not a special LLVM global!");
1236 if (GV->getName() == "llvm.global_ctors") {
1237 EmitXXStructorList(GV->getInitializer(), /* isCtor */ true);
1239 if (TM.getRelocationModel() == Reloc::Static &&
1240 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1241 StringRef Sym(".constructors_used");
1242 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1248 if (GV->getName() == "llvm.global_dtors") {
1249 EmitXXStructorList(GV->getInitializer(), /* isCtor */ false);
1251 if (TM.getRelocationModel() == Reloc::Static &&
1252 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1253 StringRef Sym(".destructors_used");
1254 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1263 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1264 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1265 /// is true, as being used with this directive.
1266 void AsmPrinter::EmitLLVMUsedList(const ConstantArray *InitList) {
1267 // Should be an array of 'i8*'.
1268 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1269 const GlobalValue *GV =
1270 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1271 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
1272 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip);
1276 typedef std::pair<unsigned, Constant*> Structor;
1278 static bool priority_order(const Structor& lhs, const Structor& rhs) {
1279 return lhs.first < rhs.first;
1282 /// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
1284 void AsmPrinter::EmitXXStructorList(const Constant *List, bool isCtor) {
1285 // Should be an array of '{ int, void ()* }' structs. The first value is the
1287 if (!isa<ConstantArray>(List)) return;
1289 // Sanity check the structors list.
1290 const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1291 if (!InitList) return; // Not an array!
1292 StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType());
1293 if (!ETy || ETy->getNumElements() != 2) return; // Not an array of pairs!
1294 if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) ||
1295 !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr).
1297 // Gather the structors in a form that's convenient for sorting by priority.
1298 SmallVector<Structor, 8> Structors;
1299 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1300 ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i));
1301 if (!CS) continue; // Malformed.
1302 if (CS->getOperand(1)->isNullValue())
1303 break; // Found a null terminator, skip the rest.
1304 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
1305 if (!Priority) continue; // Malformed.
1306 Structors.push_back(std::make_pair(Priority->getLimitedValue(65535),
1307 CS->getOperand(1)));
1310 // Emit the function pointers in the target-specific order
1311 const DataLayout *TD = TM.getDataLayout();
1312 unsigned Align = Log2_32(TD->getPointerPrefAlignment());
1313 std::stable_sort(Structors.begin(), Structors.end(), priority_order);
1314 for (unsigned i = 0, e = Structors.size(); i != e; ++i) {
1315 const MCSection *OutputSection =
1317 getObjFileLowering().getStaticCtorSection(Structors[i].first) :
1318 getObjFileLowering().getStaticDtorSection(Structors[i].first));
1319 OutStreamer.SwitchSection(OutputSection);
1320 if (OutStreamer.getCurrentSection() != OutStreamer.getPreviousSection())
1321 EmitAlignment(Align);
1322 EmitXXStructor(Structors[i].second);
1326 //===--------------------------------------------------------------------===//
1327 // Emission and print routines
1330 /// EmitInt8 - Emit a byte directive and value.
1332 void AsmPrinter::EmitInt8(int Value) const {
1333 OutStreamer.EmitIntValue(Value, 1);
1336 /// EmitInt16 - Emit a short directive and value.
1338 void AsmPrinter::EmitInt16(int Value) const {
1339 OutStreamer.EmitIntValue(Value, 2);
1342 /// EmitInt32 - Emit a long directive and value.
1344 void AsmPrinter::EmitInt32(int Value) const {
1345 OutStreamer.EmitIntValue(Value, 4);
1348 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
1349 /// in bytes of the directive is specified by Size and Hi/Lo specify the
1350 /// labels. This implicitly uses .set if it is available.
1351 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1352 unsigned Size) const {
1353 // Get the Hi-Lo expression.
1354 const MCExpr *Diff =
1355 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1356 MCSymbolRefExpr::Create(Lo, OutContext),
1359 if (!MAI->hasSetDirective()) {
1360 OutStreamer.EmitValue(Diff, Size);
1364 // Otherwise, emit with .set (aka assignment).
1365 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1366 OutStreamer.EmitAssignment(SetLabel, Diff);
1367 OutStreamer.EmitSymbolValue(SetLabel, Size);
1370 /// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo"
1371 /// where the size in bytes of the directive is specified by Size and Hi/Lo
1372 /// specify the labels. This implicitly uses .set if it is available.
1373 void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset,
1374 const MCSymbol *Lo, unsigned Size)
1377 // Emit Hi+Offset - Lo
1378 // Get the Hi+Offset expression.
1379 const MCExpr *Plus =
1380 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext),
1381 MCConstantExpr::Create(Offset, OutContext),
1384 // Get the Hi+Offset-Lo expression.
1385 const MCExpr *Diff =
1386 MCBinaryExpr::CreateSub(Plus,
1387 MCSymbolRefExpr::Create(Lo, OutContext),
1390 if (!MAI->hasSetDirective())
1391 OutStreamer.EmitValue(Diff, 4);
1393 // Otherwise, emit with .set (aka assignment).
1394 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1395 OutStreamer.EmitAssignment(SetLabel, Diff);
1396 OutStreamer.EmitSymbolValue(SetLabel, 4);
1400 /// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
1401 /// where the size in bytes of the directive is specified by Size and Label
1402 /// specifies the label. This implicitly uses .set if it is available.
1403 void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset,
1407 // Emit Label+Offset (or just Label if Offset is zero)
1408 const MCExpr *Expr = MCSymbolRefExpr::Create(Label, OutContext);
1410 Expr = MCBinaryExpr::CreateAdd(Expr,
1411 MCConstantExpr::Create(Offset, OutContext),
1414 OutStreamer.EmitValue(Expr, Size);
1418 //===----------------------------------------------------------------------===//
1420 // EmitAlignment - Emit an alignment directive to the specified power of
1421 // two boundary. For example, if you pass in 3 here, you will get an 8
1422 // byte alignment. If a global value is specified, and if that global has
1423 // an explicit alignment requested, it will override the alignment request
1424 // if required for correctness.
1426 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV) const {
1427 if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getDataLayout(), NumBits);
1429 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.
1431 if (getCurrentSection()->getKind().isText())
1432 OutStreamer.EmitCodeAlignment(1 << NumBits);
1434 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
1437 //===----------------------------------------------------------------------===//
1438 // Constant emission.
1439 //===----------------------------------------------------------------------===//
1441 /// lowerConstant - Lower the specified LLVM Constant to an MCExpr.
1443 static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP) {
1444 MCContext &Ctx = AP.OutContext;
1446 if (CV->isNullValue() || isa<UndefValue>(CV))
1447 return MCConstantExpr::Create(0, Ctx);
1449 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1450 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1452 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1453 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx);
1455 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1456 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1458 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1460 llvm_unreachable("Unknown constant value to lower!");
1463 switch (CE->getOpcode()) {
1465 // If the code isn't optimized, there may be outstanding folding
1466 // opportunities. Attempt to fold the expression using DataLayout as a
1467 // last resort before giving up.
1469 ConstantFoldConstantExpression(CE, AP.TM.getDataLayout()))
1471 return lowerConstant(C, AP);
1473 // Otherwise report the problem to the user.
1476 raw_string_ostream OS(S);
1477 OS << "Unsupported expression in static initializer: ";
1478 WriteAsOperand(OS, CE, /*PrintType=*/false,
1479 !AP.MF ? 0 : AP.MF->getFunction()->getParent());
1480 report_fatal_error(OS.str());
1482 case Instruction::GetElementPtr: {
1483 const DataLayout &TD = *AP.TM.getDataLayout();
1484 // Generate a symbolic expression for the byte address
1485 APInt OffsetAI(TD.getPointerSizeInBits(), 0);
1486 cast<GEPOperator>(CE)->accumulateConstantOffset(TD, OffsetAI);
1488 const MCExpr *Base = lowerConstant(CE->getOperand(0), AP);
1492 int64_t Offset = OffsetAI.getSExtValue();
1493 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1497 case Instruction::Trunc:
1498 // We emit the value and depend on the assembler to truncate the generated
1499 // expression properly. This is important for differences between
1500 // blockaddress labels. Since the two labels are in the same function, it
1501 // is reasonable to treat their delta as a 32-bit value.
1503 case Instruction::BitCast:
1504 return lowerConstant(CE->getOperand(0), AP);
1506 case Instruction::IntToPtr: {
1507 const DataLayout &TD = *AP.TM.getDataLayout();
1508 // Handle casts to pointers by changing them into casts to the appropriate
1509 // integer type. This promotes constant folding and simplifies this code.
1510 Constant *Op = CE->getOperand(0);
1511 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
1513 return lowerConstant(Op, AP);
1516 case Instruction::PtrToInt: {
1517 const DataLayout &TD = *AP.TM.getDataLayout();
1518 // Support only foldable casts to/from pointers that can be eliminated by
1519 // changing the pointer to the appropriately sized integer type.
1520 Constant *Op = CE->getOperand(0);
1521 Type *Ty = CE->getType();
1523 const MCExpr *OpExpr = lowerConstant(Op, AP);
1525 // We can emit the pointer value into this slot if the slot is an
1526 // integer slot equal to the size of the pointer.
1527 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
1530 // Otherwise the pointer is smaller than the resultant integer, mask off
1531 // the high bits so we are sure to get a proper truncation if the input is
1533 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
1534 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1535 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1538 // The MC library also has a right-shift operator, but it isn't consistently
1539 // signed or unsigned between different targets.
1540 case Instruction::Add:
1541 case Instruction::Sub:
1542 case Instruction::Mul:
1543 case Instruction::SDiv:
1544 case Instruction::SRem:
1545 case Instruction::Shl:
1546 case Instruction::And:
1547 case Instruction::Or:
1548 case Instruction::Xor: {
1549 const MCExpr *LHS = lowerConstant(CE->getOperand(0), AP);
1550 const MCExpr *RHS = lowerConstant(CE->getOperand(1), AP);
1551 switch (CE->getOpcode()) {
1552 default: llvm_unreachable("Unknown binary operator constant cast expr");
1553 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1554 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1555 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1556 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1557 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1558 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1559 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1560 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1561 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1567 static void emitGlobalConstantImpl(const Constant *C, unsigned AddrSpace,
1570 /// isRepeatedByteSequence - Determine whether the given value is
1571 /// composed of a repeated sequence of identical bytes and return the
1572 /// byte value. If it is not a repeated sequence, return -1.
1573 static int isRepeatedByteSequence(const ConstantDataSequential *V) {
1574 StringRef Data = V->getRawDataValues();
1575 assert(!Data.empty() && "Empty aggregates should be CAZ node");
1577 for (unsigned i = 1, e = Data.size(); i != e; ++i)
1578 if (Data[i] != C) return -1;
1579 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1.
1583 /// isRepeatedByteSequence - Determine whether the given value is
1584 /// composed of a repeated sequence of identical bytes and return the
1585 /// byte value. If it is not a repeated sequence, return -1.
1586 static int isRepeatedByteSequence(const Value *V, TargetMachine &TM) {
1588 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
1589 if (CI->getBitWidth() > 64) return -1;
1591 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(V->getType());
1592 uint64_t Value = CI->getZExtValue();
1594 // Make sure the constant is at least 8 bits long and has a power
1595 // of 2 bit width. This guarantees the constant bit width is
1596 // always a multiple of 8 bits, avoiding issues with padding out
1597 // to Size and other such corner cases.
1598 if (CI->getBitWidth() < 8 || !isPowerOf2_64(CI->getBitWidth())) return -1;
1600 uint8_t Byte = static_cast<uint8_t>(Value);
1602 for (unsigned i = 1; i < Size; ++i) {
1604 if (static_cast<uint8_t>(Value) != Byte) return -1;
1608 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) {
1609 // Make sure all array elements are sequences of the same repeated
1611 assert(CA->getNumOperands() != 0 && "Should be a CAZ");
1612 int Byte = isRepeatedByteSequence(CA->getOperand(0), TM);
1613 if (Byte == -1) return -1;
1615 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i) {
1616 int ThisByte = isRepeatedByteSequence(CA->getOperand(i), TM);
1617 if (ThisByte == -1) return -1;
1618 if (Byte != ThisByte) return -1;
1623 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V))
1624 return isRepeatedByteSequence(CDS);
1629 static void emitGlobalConstantDataSequential(const ConstantDataSequential *CDS,
1630 unsigned AddrSpace,AsmPrinter &AP){
1632 // See if we can aggregate this into a .fill, if so, emit it as such.
1633 int Value = isRepeatedByteSequence(CDS, AP.TM);
1635 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CDS->getType());
1636 // Don't emit a 1-byte object as a .fill.
1638 return AP.OutStreamer.EmitFill(Bytes, Value, AddrSpace);
1641 // If this can be emitted with .ascii/.asciz, emit it as such.
1642 if (CDS->isString())
1643 return AP.OutStreamer.EmitBytes(CDS->getAsString(), AddrSpace);
1645 // Otherwise, emit the values in successive locations.
1646 unsigned ElementByteSize = CDS->getElementByteSize();
1647 if (isa<IntegerType>(CDS->getElementType())) {
1648 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1650 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1651 CDS->getElementAsInteger(i));
1652 AP.OutStreamer.EmitIntValue(CDS->getElementAsInteger(i),
1653 ElementByteSize, AddrSpace);
1655 } else if (ElementByteSize == 4) {
1656 // FP Constants are printed as integer constants to avoid losing
1658 assert(CDS->getElementType()->isFloatTy());
1659 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1665 F = CDS->getElementAsFloat(i);
1667 AP.OutStreamer.GetCommentOS() << "float " << F << '\n';
1668 AP.OutStreamer.EmitIntValue(I, 4, AddrSpace);
1671 assert(CDS->getElementType()->isDoubleTy());
1672 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1678 F = CDS->getElementAsDouble(i);
1680 AP.OutStreamer.GetCommentOS() << "double " << F << '\n';
1681 AP.OutStreamer.EmitIntValue(I, 8, AddrSpace);
1685 const DataLayout &TD = *AP.TM.getDataLayout();
1686 unsigned Size = TD.getTypeAllocSize(CDS->getType());
1687 unsigned EmittedSize = TD.getTypeAllocSize(CDS->getType()->getElementType()) *
1688 CDS->getNumElements();
1689 if (unsigned Padding = Size - EmittedSize)
1690 AP.OutStreamer.EmitZeros(Padding, AddrSpace);
1694 static void emitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
1696 // See if we can aggregate some values. Make sure it can be
1697 // represented as a series of bytes of the constant value.
1698 int Value = isRepeatedByteSequence(CA, AP.TM);
1701 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CA->getType());
1702 AP.OutStreamer.EmitFill(Bytes, Value, AddrSpace);
1705 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1706 emitGlobalConstantImpl(CA->getOperand(i), AddrSpace, AP);
1710 static void emitGlobalConstantVector(const ConstantVector *CV,
1711 unsigned AddrSpace, AsmPrinter &AP) {
1712 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1713 emitGlobalConstantImpl(CV->getOperand(i), AddrSpace, AP);
1715 const DataLayout &TD = *AP.TM.getDataLayout();
1716 unsigned Size = TD.getTypeAllocSize(CV->getType());
1717 unsigned EmittedSize = TD.getTypeAllocSize(CV->getType()->getElementType()) *
1718 CV->getType()->getNumElements();
1719 if (unsigned Padding = Size - EmittedSize)
1720 AP.OutStreamer.EmitZeros(Padding, AddrSpace);
1723 static void emitGlobalConstantStruct(const ConstantStruct *CS,
1724 unsigned AddrSpace, AsmPrinter &AP) {
1725 // Print the fields in successive locations. Pad to align if needed!
1726 const DataLayout *TD = AP.TM.getDataLayout();
1727 unsigned Size = TD->getTypeAllocSize(CS->getType());
1728 const StructLayout *Layout = TD->getStructLayout(CS->getType());
1729 uint64_t SizeSoFar = 0;
1730 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1731 const Constant *Field = CS->getOperand(i);
1733 // Check if padding is needed and insert one or more 0s.
1734 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
1735 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1736 - Layout->getElementOffset(i)) - FieldSize;
1737 SizeSoFar += FieldSize + PadSize;
1739 // Now print the actual field value.
1740 emitGlobalConstantImpl(Field, AddrSpace, AP);
1742 // Insert padding - this may include padding to increase the size of the
1743 // current field up to the ABI size (if the struct is not packed) as well
1744 // as padding to ensure that the next field starts at the right offset.
1745 AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
1747 assert(SizeSoFar == Layout->getSizeInBytes() &&
1748 "Layout of constant struct may be incorrect!");
1751 static void emitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
1753 APInt API = CFP->getValueAPF().bitcastToAPInt();
1755 // First print a comment with what we think the original floating-point value
1756 // should have been.
1757 if (AP.isVerbose()) {
1758 SmallString<8> StrVal;
1759 CFP->getValueAPF().toString(StrVal);
1761 CFP->getType()->print(AP.OutStreamer.GetCommentOS());
1762 AP.OutStreamer.GetCommentOS() << ' ' << StrVal << '\n';
1765 // Now iterate through the APInt chunks, emitting them in endian-correct
1766 // order, possibly with a smaller chunk at beginning/end (e.g. for x87 80-bit
1768 unsigned NumBytes = API.getBitWidth() / 8;
1769 unsigned TrailingBytes = NumBytes % sizeof(uint64_t);
1770 const uint64_t *p = API.getRawData();
1772 // PPC's long double has odd notions of endianness compared to how LLVM
1773 // handles it: p[0] goes first for *big* endian on PPC.
1774 if (AP.TM.getDataLayout()->isBigEndian() != CFP->getType()->isPPC_FP128Ty()) {
1775 int Chunk = API.getNumWords() - 1;
1778 AP.OutStreamer.EmitIntValue(p[Chunk--], TrailingBytes, AddrSpace);
1780 for (; Chunk >= 0; --Chunk)
1781 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t), AddrSpace);
1784 for (Chunk = 0; Chunk < NumBytes / sizeof(uint64_t); ++Chunk)
1785 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t), AddrSpace);
1788 AP.OutStreamer.EmitIntValue(p[Chunk], TrailingBytes, AddrSpace);
1791 // Emit the tail padding for the long double.
1792 const DataLayout &TD = *AP.TM.getDataLayout();
1793 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
1794 TD.getTypeStoreSize(CFP->getType()), AddrSpace);
1797 static void emitGlobalConstantLargeInt(const ConstantInt *CI,
1798 unsigned AddrSpace, AsmPrinter &AP) {
1799 const DataLayout *TD = AP.TM.getDataLayout();
1800 unsigned BitWidth = CI->getBitWidth();
1802 // Copy the value as we may massage the layout for constants whose bit width
1803 // is not a multiple of 64-bits.
1804 APInt Realigned(CI->getValue());
1805 uint64_t ExtraBits = 0;
1806 unsigned ExtraBitsSize = BitWidth & 63;
1808 if (ExtraBitsSize) {
1809 // The bit width of the data is not a multiple of 64-bits.
1810 // The extra bits are expected to be at the end of the chunk of the memory.
1812 // * Nothing to be done, just record the extra bits to emit.
1814 // * Record the extra bits to emit.
1815 // * Realign the raw data to emit the chunks of 64-bits.
1816 if (TD->isBigEndian()) {
1817 // Basically the structure of the raw data is a chunk of 64-bits cells:
1818 // 0 1 BitWidth / 64
1819 // [chunk1][chunk2] ... [chunkN].
1820 // The most significant chunk is chunkN and it should be emitted first.
1821 // However, due to the alignment issue chunkN contains useless bits.
1822 // Realign the chunks so that they contain only useless information:
1823 // ExtraBits 0 1 (BitWidth / 64) - 1
1824 // chu[nk1 chu][nk2 chu] ... [nkN-1 chunkN]
1825 ExtraBits = Realigned.getRawData()[0] &
1826 (((uint64_t)-1) >> (64 - ExtraBitsSize));
1827 Realigned = Realigned.lshr(ExtraBitsSize);
1829 ExtraBits = Realigned.getRawData()[BitWidth / 64];
1832 // We don't expect assemblers to support integer data directives
1833 // for more than 64 bits, so we emit the data in at most 64-bit
1834 // quantities at a time.
1835 const uint64_t *RawData = Realigned.getRawData();
1836 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1837 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1838 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1841 if (ExtraBitsSize) {
1842 // Emit the extra bits after the 64-bits chunks.
1844 // Emit a directive that fills the expected size.
1845 uint64_t Size = AP.TM.getDataLayout()->getTypeAllocSize(CI->getType());
1846 Size -= (BitWidth / 64) * 8;
1847 assert(Size && Size * 8 >= ExtraBitsSize &&
1848 (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize)))
1849 == ExtraBits && "Directive too small for extra bits.");
1850 AP.OutStreamer.EmitIntValue(ExtraBits, Size, AddrSpace);
1854 static void emitGlobalConstantImpl(const Constant *CV, unsigned AddrSpace,
1856 const DataLayout *TD = AP.TM.getDataLayout();
1857 uint64_t Size = TD->getTypeAllocSize(CV->getType());
1858 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV))
1859 return AP.OutStreamer.EmitZeros(Size, AddrSpace);
1861 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1868 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1869 CI->getZExtValue());
1870 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1873 emitGlobalConstantLargeInt(CI, AddrSpace, AP);
1878 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1879 return emitGlobalConstantFP(CFP, AddrSpace, AP);
1881 if (isa<ConstantPointerNull>(CV)) {
1882 AP.OutStreamer.EmitIntValue(0, Size, AddrSpace);
1886 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV))
1887 return emitGlobalConstantDataSequential(CDS, AddrSpace, AP);
1889 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1890 return emitGlobalConstantArray(CVA, AddrSpace, AP);
1892 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1893 return emitGlobalConstantStruct(CVS, AddrSpace, AP);
1895 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
1896 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
1898 if (CE->getOpcode() == Instruction::BitCast)
1899 return emitGlobalConstantImpl(CE->getOperand(0), AddrSpace, AP);
1902 // If the constant expression's size is greater than 64-bits, then we have
1903 // to emit the value in chunks. Try to constant fold the value and emit it
1905 Constant *New = ConstantFoldConstantExpression(CE, TD);
1906 if (New && New != CE)
1907 return emitGlobalConstantImpl(New, AddrSpace, AP);
1911 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1912 return emitGlobalConstantVector(V, AddrSpace, AP);
1914 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1915 // thread the streamer with EmitValue.
1916 AP.OutStreamer.EmitValue(lowerConstant(CV, AP), Size, AddrSpace);
1919 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1920 void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1921 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(CV->getType());
1923 emitGlobalConstantImpl(CV, AddrSpace, *this);
1924 else if (MAI->hasSubsectionsViaSymbols()) {
1925 // If the global has zero size, emit a single byte so that two labels don't
1926 // look like they are at the same location.
1927 OutStreamer.EmitIntValue(0, 1, AddrSpace);
1931 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1932 // Target doesn't support this yet!
1933 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1936 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1938 OS << '+' << Offset;
1939 else if (Offset < 0)
1943 //===----------------------------------------------------------------------===//
1944 // Symbol Lowering Routines.
1945 //===----------------------------------------------------------------------===//
1947 /// GetTempSymbol - Return the MCSymbol corresponding to the assembler
1948 /// temporary label with the specified stem and unique ID.
1949 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const {
1950 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) +
1954 /// GetTempSymbol - Return an assembler temporary label with the specified
1956 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const {
1957 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix())+
1962 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
1963 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
1966 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
1967 return MMI->getAddrLabelSymbol(BB);
1970 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1971 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1972 return OutContext.GetOrCreateSymbol
1973 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
1974 + "_" + Twine(CPID));
1977 /// GetJTISymbol - Return the symbol for the specified jump table entry.
1978 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1979 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
1982 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
1983 /// FIXME: privatize to AsmPrinter.
1984 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
1985 return OutContext.GetOrCreateSymbol
1986 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
1987 Twine(UID) + "_set_" + Twine(MBBID));
1990 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1991 /// global value name as its base, with the specified suffix, and where the
1992 /// symbol is forced to have private linkage if ForcePrivate is true.
1993 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1995 bool ForcePrivate) const {
1996 SmallString<60> NameStr;
1997 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1998 NameStr.append(Suffix.begin(), Suffix.end());
1999 return OutContext.GetOrCreateSymbol(NameStr.str());
2002 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
2004 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
2005 SmallString<60> NameStr;
2006 Mang->getNameWithPrefix(NameStr, Sym);
2007 return OutContext.GetOrCreateSymbol(NameStr.str());
2012 /// PrintParentLoopComment - Print comments about parent loops of this one.
2013 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2014 unsigned FunctionNumber) {
2015 if (Loop == 0) return;
2016 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
2017 OS.indent(Loop->getLoopDepth()*2)
2018 << "Parent Loop BB" << FunctionNumber << "_"
2019 << Loop->getHeader()->getNumber()
2020 << " Depth=" << Loop->getLoopDepth() << '\n';
2024 /// PrintChildLoopComment - Print comments about child loops within
2025 /// the loop for this basic block, with nesting.
2026 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2027 unsigned FunctionNumber) {
2028 // Add child loop information
2029 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
2030 OS.indent((*CL)->getLoopDepth()*2)
2031 << "Child Loop BB" << FunctionNumber << "_"
2032 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
2034 PrintChildLoopComment(OS, *CL, FunctionNumber);
2038 /// emitBasicBlockLoopComments - Pretty-print comments for basic blocks.
2039 static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
2040 const MachineLoopInfo *LI,
2041 const AsmPrinter &AP) {
2042 // Add loop depth information
2043 const MachineLoop *Loop = LI->getLoopFor(&MBB);
2044 if (Loop == 0) return;
2046 MachineBasicBlock *Header = Loop->getHeader();
2047 assert(Header && "No header for loop");
2049 // If this block is not a loop header, just print out what is the loop header
2051 if (Header != &MBB) {
2052 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
2053 Twine(AP.getFunctionNumber())+"_" +
2054 Twine(Loop->getHeader()->getNumber())+
2055 " Depth="+Twine(Loop->getLoopDepth()));
2059 // Otherwise, it is a loop header. Print out information about child and
2061 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
2063 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
2066 OS.indent(Loop->getLoopDepth()*2-2);
2071 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
2073 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
2077 /// EmitBasicBlockStart - This method prints the label for the specified
2078 /// MachineBasicBlock, an alignment (if present) and a comment describing
2079 /// it if appropriate.
2080 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
2081 // Emit an alignment directive for this block, if needed.
2082 if (unsigned Align = MBB->getAlignment())
2083 EmitAlignment(Align);
2085 // If the block has its address taken, emit any labels that were used to
2086 // reference the block. It is possible that there is more than one label
2087 // here, because multiple LLVM BB's may have been RAUW'd to this block after
2088 // the references were generated.
2089 if (MBB->hasAddressTaken()) {
2090 const BasicBlock *BB = MBB->getBasicBlock();
2092 OutStreamer.AddComment("Block address taken");
2094 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
2096 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
2097 OutStreamer.EmitLabel(Syms[i]);
2100 // Print some verbose block comments.
2102 if (const BasicBlock *BB = MBB->getBasicBlock())
2104 OutStreamer.AddComment("%" + BB->getName());
2105 emitBasicBlockLoopComments(*MBB, LI, *this);
2108 // Print the main label for the block.
2109 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
2110 if (isVerbose() && OutStreamer.hasRawTextSupport()) {
2111 // NOTE: Want this comment at start of line, don't emit with AddComment.
2112 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" +
2113 Twine(MBB->getNumber()) + ":");
2116 OutStreamer.EmitLabel(MBB->getSymbol());
2120 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility,
2121 bool IsDefinition) const {
2122 MCSymbolAttr Attr = MCSA_Invalid;
2124 switch (Visibility) {
2126 case GlobalValue::HiddenVisibility:
2128 Attr = MAI->getHiddenVisibilityAttr();
2130 Attr = MAI->getHiddenDeclarationVisibilityAttr();
2132 case GlobalValue::ProtectedVisibility:
2133 Attr = MAI->getProtectedVisibilityAttr();
2137 if (Attr != MCSA_Invalid)
2138 OutStreamer.EmitSymbolAttribute(Sym, Attr);
2141 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
2142 /// exactly one predecessor and the control transfer mechanism between
2143 /// the predecessor and this block is a fall-through.
2145 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
2146 // If this is a landing pad, it isn't a fall through. If it has no preds,
2147 // then nothing falls through to it.
2148 if (MBB->isLandingPad() || MBB->pred_empty())
2151 // If there isn't exactly one predecessor, it can't be a fall through.
2152 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
2154 if (PI2 != MBB->pred_end())
2157 // The predecessor has to be immediately before this block.
2158 MachineBasicBlock *Pred = *PI;
2160 if (!Pred->isLayoutSuccessor(MBB))
2163 // If the block is completely empty, then it definitely does fall through.
2167 // Check the terminators in the previous blocks
2168 for (MachineBasicBlock::iterator II = Pred->getFirstTerminator(),
2169 IE = Pred->end(); II != IE; ++II) {
2170 MachineInstr &MI = *II;
2172 // If it is not a simple branch, we are in a table somewhere.
2173 if (!MI.isBranch() || MI.isIndirectBranch())
2176 // If we are the operands of one of the branches, this is not
2178 for (MachineInstr::mop_iterator OI = MI.operands_begin(),
2179 OE = MI.operands_end(); OI != OE; ++OI) {
2180 const MachineOperand& OP = *OI;
2183 if (OP.isMBB() && OP.getMBB() == MBB)
2193 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
2194 if (!S->usesMetadata())
2197 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
2198 gcp_map_type::iterator GCPI = GCMap.find(S);
2199 if (GCPI != GCMap.end())
2200 return GCPI->second;
2202 const char *Name = S->getName().c_str();
2204 for (GCMetadataPrinterRegistry::iterator
2205 I = GCMetadataPrinterRegistry::begin(),
2206 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
2207 if (strcmp(Name, I->getName()) == 0) {
2208 GCMetadataPrinter *GMP = I->instantiate();
2210 GCMap.insert(std::make_pair(S, GMP));
2214 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));