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/CodeGen/GCMetadataPrinter.h"
22 #include "llvm/CodeGen/MachineConstantPool.h"
23 #include "llvm/CodeGen/MachineFrameInfo.h"
24 #include "llvm/CodeGen/MachineFunction.h"
25 #include "llvm/CodeGen/MachineInstrBundle.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/Mangler.h"
32 #include "llvm/IR/Module.h"
33 #include "llvm/IR/Operator.h"
34 #include "llvm/MC/MCAsmInfo.h"
35 #include "llvm/MC/MCContext.h"
36 #include "llvm/MC/MCExpr.h"
37 #include "llvm/MC/MCInst.h"
38 #include "llvm/MC/MCSection.h"
39 #include "llvm/MC/MCStreamer.h"
40 #include "llvm/MC/MCSymbol.h"
41 #include "llvm/Support/ErrorHandling.h"
42 #include "llvm/Support/Format.h"
43 #include "llvm/Support/MathExtras.h"
44 #include "llvm/Support/Timer.h"
45 #include "llvm/Target/TargetFrameLowering.h"
46 #include "llvm/Target/TargetInstrInfo.h"
47 #include "llvm/Target/TargetLowering.h"
48 #include "llvm/Target/TargetLoweringObjectFile.h"
49 #include "llvm/Target/TargetOptions.h"
50 #include "llvm/Target/TargetRegisterInfo.h"
51 #include "llvm/Transforms/Utils/GlobalStatus.h"
52 #include "WinCodeViewLineTables.h"
55 static const char *const DWARFGroupName = "DWARF Emission";
56 static const char *const DbgTimerName = "Debug Info Emission";
57 static const char *const EHTimerName = "DWARF Exception Writer";
58 static const char *const CodeViewLineTablesGroupName = "CodeView Line Tables";
60 STATISTIC(EmittedInsts, "Number of machine instrs printed");
62 char AsmPrinter::ID = 0;
64 typedef DenseMap<GCStrategy*,GCMetadataPrinter*> gcp_map_type;
65 static gcp_map_type &getGCMap(void *&P) {
67 P = new gcp_map_type();
68 return *(gcp_map_type*)P;
72 /// getGVAlignmentLog2 - Return the alignment to use for the specified global
73 /// value in log2 form. This rounds up to the preferred alignment if possible
75 static unsigned getGVAlignmentLog2(const GlobalValue *GV, const DataLayout &TD,
76 unsigned InBits = 0) {
78 if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV))
79 NumBits = TD.getPreferredAlignmentLog(GVar);
81 // If InBits is specified, round it to it.
85 // If the GV has a specified alignment, take it into account.
86 if (GV->getAlignment() == 0)
89 unsigned GVAlign = Log2_32(GV->getAlignment());
91 // If the GVAlign is larger than NumBits, or if we are required to obey
92 // NumBits because the GV has an assigned section, obey it.
93 if (GVAlign > NumBits || GV->hasSection())
98 AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
99 : MachineFunctionPass(ID),
100 TM(tm), MAI(tm.getMCAsmInfo()), MII(tm.getInstrInfo()),
101 OutContext(Streamer.getContext()),
102 OutStreamer(Streamer),
103 LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {
104 DD = 0; MMI = 0; LI = 0; MF = 0;
105 CurrentFnSym = CurrentFnSymForSize = 0;
106 GCMetadataPrinters = 0;
107 VerboseAsm = Streamer.isVerboseAsm();
110 AsmPrinter::~AsmPrinter() {
111 assert(DD == 0 && Handlers.empty() && "Debug/EH info didn't get finalized");
113 if (GCMetadataPrinters != 0) {
114 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
116 for (gcp_map_type::iterator I = GCMap.begin(), E = GCMap.end(); I != E; ++I)
119 GCMetadataPrinters = 0;
125 /// getFunctionNumber - Return a unique ID for the current function.
127 unsigned AsmPrinter::getFunctionNumber() const {
128 return MF->getFunctionNumber();
131 const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
132 return TM.getTargetLowering()->getObjFileLowering();
135 /// getDataLayout - Return information about data layout.
136 const DataLayout &AsmPrinter::getDataLayout() const {
137 return *TM.getDataLayout();
140 StringRef AsmPrinter::getTargetTriple() const {
141 return TM.getTargetTriple();
144 /// getCurrentSection() - Return the current section we are emitting to.
145 const MCSection *AsmPrinter::getCurrentSection() const {
146 return OutStreamer.getCurrentSection().first;
151 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
152 AU.setPreservesAll();
153 MachineFunctionPass::getAnalysisUsage(AU);
154 AU.addRequired<MachineModuleInfo>();
155 AU.addRequired<GCModuleInfo>();
157 AU.addRequired<MachineLoopInfo>();
160 bool AsmPrinter::doInitialization(Module &M) {
161 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
162 MMI->AnalyzeModule(M);
164 // Initialize TargetLoweringObjectFile.
165 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
166 .Initialize(OutContext, TM);
168 OutStreamer.InitSections(false);
170 Mang = new Mangler(TM.getDataLayout());
172 // Allow the target to emit any magic that it wants at the start of the file.
173 EmitStartOfAsmFile(M);
175 // Very minimal debug info. It is ignored if we emit actual debug info. If we
176 // don't, this at least helps the user find where a global came from.
177 if (MAI->hasSingleParameterDotFile()) {
179 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
182 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
183 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
184 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
185 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
186 MP->beginAssembly(*this);
188 // Emit module-level inline asm if it exists.
189 if (!M.getModuleInlineAsm().empty()) {
190 OutStreamer.AddComment("Start of file scope inline assembly");
191 OutStreamer.AddBlankLine();
192 EmitInlineAsm(M.getModuleInlineAsm()+"\n");
193 OutStreamer.AddComment("End of file scope inline assembly");
194 OutStreamer.AddBlankLine();
197 if (MAI->doesSupportDebugInformation()) {
198 if (Triple(TM.getTargetTriple()).getOS() == Triple::Win32) {
199 Handlers.push_back(HandlerInfo(new WinCodeViewLineTables(this),
201 CodeViewLineTablesGroupName));
203 DD = new DwarfDebug(this, &M);
204 Handlers.push_back(HandlerInfo(DD, DbgTimerName, DWARFGroupName));
208 DwarfException *DE = 0;
209 switch (MAI->getExceptionHandlingType()) {
210 case ExceptionHandling::None:
212 case ExceptionHandling::SjLj:
213 case ExceptionHandling::DwarfCFI:
214 DE = new DwarfCFIException(this);
216 case ExceptionHandling::ARM:
217 DE = new ARMException(this);
219 case ExceptionHandling::Win64:
220 DE = new Win64Exception(this);
224 Handlers.push_back(HandlerInfo(DE, EHTimerName, DWARFGroupName));
228 void AsmPrinter::EmitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const {
229 GlobalValue::LinkageTypes Linkage = GV->getLinkage();
231 case GlobalValue::CommonLinkage:
232 case GlobalValue::LinkOnceAnyLinkage:
233 case GlobalValue::LinkOnceODRLinkage:
234 case GlobalValue::WeakAnyLinkage:
235 case GlobalValue::WeakODRLinkage:
236 case GlobalValue::LinkerPrivateWeakLinkage:
237 if (MAI->hasWeakDefDirective()) {
239 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
241 bool CanBeHidden = false;
243 if (Linkage == GlobalValue::LinkOnceODRLinkage &&
244 MAI->hasWeakDefCanBeHiddenDirective()) {
245 if (GV->hasUnnamedAddr()) {
249 if (!GlobalStatus::analyzeGlobal(GV, GS) && !GS.IsCompared)
255 // .weak_definition _foo
256 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
258 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefAutoPrivate);
259 } else if (MAI->hasLinkOnceDirective()) {
261 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
262 //NOTE: linkonce is handled by the section the symbol was assigned to.
265 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
268 case GlobalValue::AppendingLinkage:
269 // FIXME: appending linkage variables should go into a section of
270 // their name or something. For now, just emit them as external.
271 case GlobalValue::ExternalLinkage:
272 // If external or appending, declare as a global symbol.
274 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
276 case GlobalValue::PrivateLinkage:
277 case GlobalValue::InternalLinkage:
278 case GlobalValue::LinkerPrivateLinkage:
280 case GlobalValue::AvailableExternallyLinkage:
281 llvm_unreachable("Should never emit this");
282 case GlobalValue::ExternalWeakLinkage:
283 llvm_unreachable("Don't know how to emit these");
285 llvm_unreachable("Unknown linkage type!");
288 MCSymbol *AsmPrinter::getSymbol(const GlobalValue *GV) const {
289 return getObjFileLowering().getSymbol(*Mang, GV);
292 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
293 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
294 if (GV->hasInitializer()) {
295 // Check to see if this is a special global used by LLVM, if so, emit it.
296 if (EmitSpecialLLVMGlobal(GV))
300 GV->printAsOperand(OutStreamer.GetCommentOS(),
301 /*PrintType=*/false, GV->getParent());
302 OutStreamer.GetCommentOS() << '\n';
306 MCSymbol *GVSym = getSymbol(GV);
307 EmitVisibility(GVSym, GV->getVisibility(), !GV->isDeclaration());
309 if (!GV->hasInitializer()) // External globals require no extra code.
312 if (MAI->hasDotTypeDotSizeDirective())
313 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
315 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
317 const DataLayout *DL = TM.getDataLayout();
318 uint64_t Size = DL->getTypeAllocSize(GV->getType()->getElementType());
320 // If the alignment is specified, we *must* obey it. Overaligning a global
321 // with a specified alignment is a prompt way to break globals emitted to
322 // sections and expected to be contiguous (e.g. ObjC metadata).
323 unsigned AlignLog = getGVAlignmentLog2(GV, *DL);
325 for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
326 const HandlerInfo &OI = Handlers[I];
327 NamedRegionTimer T(OI.TimerName, OI.TimerGroupName, TimePassesIsEnabled);
328 OI.Handler->setSymbolSize(GVSym, Size);
331 // Handle common and BSS local symbols (.lcomm).
332 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
333 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
334 unsigned Align = 1 << AlignLog;
336 // Handle common symbols.
337 if (GVKind.isCommon()) {
338 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
342 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
346 // Handle local BSS symbols.
347 if (MAI->hasMachoZeroFillDirective()) {
348 const MCSection *TheSection =
349 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
350 // .zerofill __DATA, __bss, _foo, 400, 5
351 OutStreamer.EmitZerofill(TheSection, GVSym, Size, Align);
355 // Use .lcomm only if it supports user-specified alignment.
356 // Otherwise, while it would still be correct to use .lcomm in some
357 // cases (e.g. when Align == 1), the external assembler might enfore
358 // some -unknown- default alignment behavior, which could cause
359 // spurious differences between external and integrated assembler.
360 // Prefer to simply fall back to .local / .comm in this case.
361 if (MAI->getLCOMMDirectiveAlignmentType() != LCOMM::NoAlignment) {
363 OutStreamer.EmitLocalCommonSymbol(GVSym, Size, Align);
367 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
371 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
373 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
377 const MCSection *TheSection =
378 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
380 // Handle the zerofill directive on darwin, which is a special form of BSS
382 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
383 if (Size == 0) Size = 1; // zerofill of 0 bytes is undefined.
386 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
387 // .zerofill __DATA, __common, _foo, 400, 5
388 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
392 // Handle thread local data for mach-o which requires us to output an
393 // additional structure of data and mangle the original symbol so that we
394 // can reference it later.
396 // TODO: This should become an "emit thread local global" method on TLOF.
397 // All of this macho specific stuff should be sunk down into TLOFMachO and
398 // stuff like "TLSExtraDataSection" should no longer be part of the parent
399 // TLOF class. This will also make it more obvious that stuff like
400 // MCStreamer::EmitTBSSSymbol is macho specific and only called from macho
402 if (GVKind.isThreadLocal() && MAI->hasMachoTBSSDirective()) {
403 // Emit the .tbss symbol
405 OutContext.GetOrCreateSymbol(GVSym->getName() + Twine("$tlv$init"));
407 if (GVKind.isThreadBSS()) {
408 TheSection = getObjFileLowering().getTLSBSSSection();
409 OutStreamer.EmitTBSSSymbol(TheSection, MangSym, Size, 1 << AlignLog);
410 } else if (GVKind.isThreadData()) {
411 OutStreamer.SwitchSection(TheSection);
413 EmitAlignment(AlignLog, GV);
414 OutStreamer.EmitLabel(MangSym);
416 EmitGlobalConstant(GV->getInitializer());
419 OutStreamer.AddBlankLine();
421 // Emit the variable struct for the runtime.
422 const MCSection *TLVSect
423 = getObjFileLowering().getTLSExtraDataSection();
425 OutStreamer.SwitchSection(TLVSect);
426 // Emit the linkage here.
427 EmitLinkage(GV, GVSym);
428 OutStreamer.EmitLabel(GVSym);
430 // Three pointers in size:
431 // - __tlv_bootstrap - used to make sure support exists
432 // - spare pointer, used when mapped by the runtime
433 // - pointer to mangled symbol above with initializer
434 unsigned PtrSize = DL->getPointerTypeSize(GV->getType());
435 OutStreamer.EmitSymbolValue(GetExternalSymbolSymbol("_tlv_bootstrap"),
437 OutStreamer.EmitIntValue(0, PtrSize);
438 OutStreamer.EmitSymbolValue(MangSym, PtrSize);
440 OutStreamer.AddBlankLine();
444 OutStreamer.SwitchSection(TheSection);
446 EmitLinkage(GV, GVSym);
447 EmitAlignment(AlignLog, GV);
449 OutStreamer.EmitLabel(GVSym);
451 EmitGlobalConstant(GV->getInitializer());
453 if (MAI->hasDotTypeDotSizeDirective())
455 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
457 OutStreamer.AddBlankLine();
460 /// EmitFunctionHeader - This method emits the header for the current
462 void AsmPrinter::EmitFunctionHeader() {
463 // Print out constants referenced by the function
466 // Print the 'header' of function.
467 const Function *F = MF->getFunction();
469 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
470 EmitVisibility(CurrentFnSym, F->getVisibility());
472 EmitLinkage(F, CurrentFnSym);
473 EmitAlignment(MF->getAlignment(), F);
475 if (MAI->hasDotTypeDotSizeDirective())
476 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
479 F->printAsOperand(OutStreamer.GetCommentOS(),
480 /*PrintType=*/false, F->getParent());
481 OutStreamer.GetCommentOS() << '\n';
484 // Emit the CurrentFnSym. This is a virtual function to allow targets to
485 // do their wild and crazy things as required.
486 EmitFunctionEntryLabel();
488 // If the function had address-taken blocks that got deleted, then we have
489 // references to the dangling symbols. Emit them at the start of the function
490 // so that we don't get references to undefined symbols.
491 std::vector<MCSymbol*> DeadBlockSyms;
492 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
493 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
494 OutStreamer.AddComment("Address taken block that was later removed");
495 OutStreamer.EmitLabel(DeadBlockSyms[i]);
498 // Emit pre-function debug and/or EH information.
499 for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
500 const HandlerInfo &OI = Handlers[I];
501 NamedRegionTimer T(OI.TimerName, OI.TimerGroupName, TimePassesIsEnabled);
502 OI.Handler->beginFunction(MF);
505 // Emit the prefix data.
506 if (F->hasPrefixData())
507 EmitGlobalConstant(F->getPrefixData());
510 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
511 /// function. This can be overridden by targets as required to do custom stuff.
512 void AsmPrinter::EmitFunctionEntryLabel() {
513 // The function label could have already been emitted if two symbols end up
514 // conflicting due to asm renaming. Detect this and emit an error.
515 if (CurrentFnSym->isUndefined())
516 return OutStreamer.EmitLabel(CurrentFnSym);
518 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
519 "' label emitted multiple times to assembly file");
522 /// emitComments - Pretty-print comments for instructions.
523 static void emitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
524 const MachineFunction *MF = MI.getParent()->getParent();
525 const TargetMachine &TM = MF->getTarget();
527 // Check for spills and reloads
530 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
532 // We assume a single instruction only has a spill or reload, not
534 const MachineMemOperand *MMO;
535 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
536 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
537 MMO = *MI.memoperands_begin();
538 CommentOS << MMO->getSize() << "-byte Reload\n";
540 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
541 if (FrameInfo->isSpillSlotObjectIndex(FI))
542 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
543 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
544 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
545 MMO = *MI.memoperands_begin();
546 CommentOS << MMO->getSize() << "-byte Spill\n";
548 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
549 if (FrameInfo->isSpillSlotObjectIndex(FI))
550 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
553 // Check for spill-induced copies
554 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
555 CommentOS << " Reload Reuse\n";
558 /// emitImplicitDef - This method emits the specified machine instruction
559 /// that is an implicit def.
560 void AsmPrinter::emitImplicitDef(const MachineInstr *MI) const {
561 unsigned RegNo = MI->getOperand(0).getReg();
562 OutStreamer.AddComment(Twine("implicit-def: ") +
563 TM.getRegisterInfo()->getName(RegNo));
564 OutStreamer.AddBlankLine();
567 static void emitKill(const MachineInstr *MI, AsmPrinter &AP) {
568 std::string Str = "kill:";
569 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
570 const MachineOperand &Op = MI->getOperand(i);
571 assert(Op.isReg() && "KILL instruction must have only register operands");
573 Str += AP.TM.getRegisterInfo()->getName(Op.getReg());
574 Str += (Op.isDef() ? "<def>" : "<kill>");
576 AP.OutStreamer.AddComment(Str);
577 AP.OutStreamer.AddBlankLine();
580 /// emitDebugValueComment - This method handles the target-independent form
581 /// of DBG_VALUE, returning true if it was able to do so. A false return
582 /// means the target will need to handle MI in EmitInstruction.
583 static bool emitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
584 // This code handles only the 3-operand target-independent form.
585 if (MI->getNumOperands() != 3)
588 SmallString<128> Str;
589 raw_svector_ostream OS(Str);
590 OS << "DEBUG_VALUE: ";
592 DIVariable V(MI->getOperand(2).getMetadata());
593 if (V.getContext().isSubprogram()) {
594 StringRef Name = DISubprogram(V.getContext()).getDisplayName();
598 OS << V.getName() << " <- ";
600 // The second operand is only an offset if it's an immediate.
601 bool Deref = MI->getOperand(0).isReg() && MI->getOperand(1).isImm();
602 int64_t Offset = Deref ? MI->getOperand(1).getImm() : 0;
604 // Register or immediate value. Register 0 means undef.
605 if (MI->getOperand(0).isFPImm()) {
606 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
607 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
608 OS << (double)APF.convertToFloat();
609 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
610 OS << APF.convertToDouble();
612 // There is no good way to print long double. Convert a copy to
613 // double. Ah well, it's only a comment.
615 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
617 OS << "(long double) " << APF.convertToDouble();
619 } else if (MI->getOperand(0).isImm()) {
620 OS << MI->getOperand(0).getImm();
621 } else if (MI->getOperand(0).isCImm()) {
622 MI->getOperand(0).getCImm()->getValue().print(OS, false /*isSigned*/);
625 if (MI->getOperand(0).isReg()) {
626 Reg = MI->getOperand(0).getReg();
628 assert(MI->getOperand(0).isFI() && "Unknown operand type");
629 const TargetFrameLowering *TFI = AP.TM.getFrameLowering();
630 Offset += TFI->getFrameIndexReference(*AP.MF,
631 MI->getOperand(0).getIndex(), Reg);
635 // Suppress offset, it is not meaningful here.
637 // NOTE: Want this comment at start of line, don't emit with AddComment.
638 AP.OutStreamer.emitRawComment(OS.str());
643 OS << AP.TM.getRegisterInfo()->getName(Reg);
647 OS << '+' << Offset << ']';
649 // NOTE: Want this comment at start of line, don't emit with AddComment.
650 AP.OutStreamer.emitRawComment(OS.str());
654 AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() {
655 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI &&
656 MF->getFunction()->needsUnwindTableEntry())
659 if (MMI->hasDebugInfo())
665 bool AsmPrinter::needsSEHMoves() {
666 return MAI->getExceptionHandlingType() == ExceptionHandling::Win64 &&
667 MF->getFunction()->needsUnwindTableEntry();
670 void AsmPrinter::emitPrologLabel(const MachineInstr &MI) {
671 const MCSymbol *Label = MI.getOperand(0).getMCSymbol();
673 if (MAI->getExceptionHandlingType() != ExceptionHandling::DwarfCFI)
676 if (needsCFIMoves() == CFI_M_None)
679 if (MMI->getCompactUnwindEncoding() != 0)
680 OutStreamer.EmitCompactUnwindEncoding(MMI->getCompactUnwindEncoding());
682 const MachineModuleInfo &MMI = MF->getMMI();
683 const std::vector<MCCFIInstruction> &Instrs = MMI.getFrameInstructions();
684 bool FoundOne = false;
686 for (std::vector<MCCFIInstruction>::const_iterator I = Instrs.begin(),
687 E = Instrs.end(); I != E; ++I) {
688 if (I->getLabel() == Label) {
689 emitCFIInstruction(*I);
696 /// EmitFunctionBody - This method emits the body and trailer for a
698 void AsmPrinter::EmitFunctionBody() {
699 // Emit target-specific gunk before the function body.
700 EmitFunctionBodyStart();
702 bool ShouldPrintDebugScopes = MMI->hasDebugInfo();
704 // Print out code for the function.
705 bool HasAnyRealCode = false;
706 const MachineInstr *LastMI = 0;
707 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
709 // Print a label for the basic block.
710 EmitBasicBlockStart(I);
711 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
715 // Print the assembly for the instruction.
716 if (!II->isLabel() && !II->isImplicitDef() && !II->isKill() &&
717 !II->isDebugValue()) {
718 HasAnyRealCode = true;
722 if (ShouldPrintDebugScopes) {
723 for (unsigned III = 0, EEE = Handlers.size(); III != EEE; ++III) {
724 const HandlerInfo &OI = Handlers[III];
725 NamedRegionTimer T(OI.TimerName, OI.TimerGroupName,
726 TimePassesIsEnabled);
727 OI.Handler->beginInstruction(II);
732 emitComments(*II, OutStreamer.GetCommentOS());
734 switch (II->getOpcode()) {
735 case TargetOpcode::PROLOG_LABEL:
736 emitPrologLabel(*II);
739 case TargetOpcode::EH_LABEL:
740 case TargetOpcode::GC_LABEL:
741 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol());
743 case TargetOpcode::INLINEASM:
746 case TargetOpcode::DBG_VALUE:
748 if (!emitDebugValueComment(II, *this))
752 case TargetOpcode::IMPLICIT_DEF:
753 if (isVerbose()) emitImplicitDef(II);
755 case TargetOpcode::KILL:
756 if (isVerbose()) emitKill(II, *this);
759 if (!TM.hasMCUseLoc())
760 MCLineEntry::Make(&OutStreamer, getCurrentSection());
766 if (ShouldPrintDebugScopes) {
767 for (unsigned III = 0, EEE = Handlers.size(); III != EEE; ++III) {
768 const HandlerInfo &OI = Handlers[III];
769 NamedRegionTimer T(OI.TimerName, OI.TimerGroupName,
770 TimePassesIsEnabled);
771 OI.Handler->endInstruction();
777 // If the last instruction was a prolog label, then we have a situation where
778 // we emitted a prolog but no function body. This results in the ending prolog
779 // label equaling the end of function label and an invalid "row" in the
780 // FDE. We need to emit a noop in this situation so that the FDE's rows are
782 bool RequiresNoop = LastMI && LastMI->isPrologLabel();
784 // If the function is empty and the object file uses .subsections_via_symbols,
785 // then we need to emit *something* to the function body to prevent the
786 // labels from collapsing together. Just emit a noop.
787 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) || RequiresNoop) {
789 TM.getInstrInfo()->getNoopForMachoTarget(Noop);
790 if (Noop.getOpcode()) {
791 OutStreamer.AddComment("avoids zero-length function");
792 OutStreamer.EmitInstruction(Noop);
793 } else // Target not mc-ized yet.
794 OutStreamer.EmitRawText(StringRef("\tnop\n"));
797 const Function *F = MF->getFunction();
798 for (Function::const_iterator i = F->begin(), e = F->end(); i != e; ++i) {
799 const BasicBlock *BB = i;
800 if (!BB->hasAddressTaken())
802 MCSymbol *Sym = GetBlockAddressSymbol(BB);
803 if (Sym->isDefined())
805 OutStreamer.AddComment("Address of block that was removed by CodeGen");
806 OutStreamer.EmitLabel(Sym);
809 // Emit target-specific gunk after the function body.
810 EmitFunctionBodyEnd();
812 // If the target wants a .size directive for the size of the function, emit
814 if (MAI->hasDotTypeDotSizeDirective()) {
815 // Create a symbol for the end of function, so we can get the size as
816 // difference between the function label and the temp label.
817 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
818 OutStreamer.EmitLabel(FnEndLabel);
820 const MCExpr *SizeExp =
821 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
822 MCSymbolRefExpr::Create(CurrentFnSymForSize,
825 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
828 // Emit post-function debug and/or EH information.
829 for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
830 const HandlerInfo &OI = Handlers[I];
831 NamedRegionTimer T(OI.TimerName, OI.TimerGroupName, TimePassesIsEnabled);
832 OI.Handler->endFunction(MF);
836 // Print out jump tables referenced by the function.
839 OutStreamer.AddBlankLine();
842 /// EmitDwarfRegOp - Emit dwarf register operation.
843 void AsmPrinter::EmitDwarfRegOp(const MachineLocation &MLoc,
844 bool Indirect) const {
845 const TargetRegisterInfo *TRI = TM.getRegisterInfo();
846 int Reg = TRI->getDwarfRegNum(MLoc.getReg(), false);
848 for (MCSuperRegIterator SR(MLoc.getReg(), TRI); SR.isValid() && Reg < 0;
850 Reg = TRI->getDwarfRegNum(*SR, false);
851 // FIXME: Get the bit range this register uses of the superregister
852 // so that we can produce a DW_OP_bit_piece
855 // FIXME: Handle cases like a super register being encoded as
856 // DW_OP_reg 32 DW_OP_piece 4 DW_OP_reg 33
858 // FIXME: We have no reasonable way of handling errors in here. The
859 // caller might be in the middle of an dwarf expression. We should
860 // probably assert that Reg >= 0 once debug info generation is more mature.
862 if (MLoc.isIndirect() || Indirect) {
864 OutStreamer.AddComment(
865 dwarf::OperationEncodingString(dwarf::DW_OP_breg0 + Reg));
866 EmitInt8(dwarf::DW_OP_breg0 + Reg);
868 OutStreamer.AddComment("DW_OP_bregx");
869 EmitInt8(dwarf::DW_OP_bregx);
870 OutStreamer.AddComment(Twine(Reg));
873 EmitSLEB128(!MLoc.isIndirect() ? 0 : MLoc.getOffset());
874 if (MLoc.isIndirect() && Indirect)
875 EmitInt8(dwarf::DW_OP_deref);
878 OutStreamer.AddComment(
879 dwarf::OperationEncodingString(dwarf::DW_OP_reg0 + Reg));
880 EmitInt8(dwarf::DW_OP_reg0 + Reg);
882 OutStreamer.AddComment("DW_OP_regx");
883 EmitInt8(dwarf::DW_OP_regx);
884 OutStreamer.AddComment(Twine(Reg));
889 // FIXME: Produce a DW_OP_bit_piece if we used a superregister
892 bool AsmPrinter::doFinalization(Module &M) {
893 // Emit global variables.
894 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
896 EmitGlobalVariable(I);
898 // Emit visibility info for declarations
899 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
900 const Function &F = *I;
901 if (!F.isDeclaration())
903 GlobalValue::VisibilityTypes V = F.getVisibility();
904 if (V == GlobalValue::DefaultVisibility)
907 MCSymbol *Name = getSymbol(&F);
908 EmitVisibility(Name, V, false);
911 // Emit module flags.
912 SmallVector<Module::ModuleFlagEntry, 8> ModuleFlags;
913 M.getModuleFlagsMetadata(ModuleFlags);
914 if (!ModuleFlags.empty())
915 getObjFileLowering().emitModuleFlags(OutStreamer, ModuleFlags, Mang, TM);
917 // Make sure we wrote out everything we need.
920 // Finalize debug and EH information.
921 for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
922 const HandlerInfo &OI = Handlers[I];
923 NamedRegionTimer T(OI.TimerName, OI.TimerGroupName,
924 TimePassesIsEnabled);
925 OI.Handler->endModule();
931 // If the target wants to know about weak references, print them all.
932 if (MAI->getWeakRefDirective()) {
933 // FIXME: This is not lazy, it would be nice to only print weak references
934 // to stuff that is actually used. Note that doing so would require targets
935 // to notice uses in operands (due to constant exprs etc). This should
936 // happen with the MC stuff eventually.
938 // Print out module-level global variables here.
939 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
941 if (!I->hasExternalWeakLinkage()) continue;
942 OutStreamer.EmitSymbolAttribute(getSymbol(I), MCSA_WeakReference);
945 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
946 if (!I->hasExternalWeakLinkage()) continue;
947 OutStreamer.EmitSymbolAttribute(getSymbol(I), MCSA_WeakReference);
951 if (MAI->hasSetDirective()) {
952 OutStreamer.AddBlankLine();
953 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
955 MCSymbol *Name = getSymbol(I);
957 const GlobalValue *GV = I->getAliasedGlobal();
958 if (GV->isDeclaration()) {
959 report_fatal_error(Name->getName() +
960 ": Target doesn't support aliases to declarations");
963 MCSymbol *Target = getSymbol(GV);
965 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
966 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
967 else if (I->hasWeakLinkage() || I->hasLinkOnceLinkage())
968 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
970 assert(I->hasLocalLinkage() && "Invalid alias linkage");
972 EmitVisibility(Name, I->getVisibility());
974 // Emit the directives as assignments aka .set:
975 OutStreamer.EmitAssignment(Name,
976 MCSymbolRefExpr::Create(Target, OutContext));
980 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
981 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
982 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
983 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
984 MP->finishAssembly(*this);
986 // Emit llvm.ident metadata in an '.ident' directive.
989 // If we don't have any trampolines, then we don't require stack memory
990 // to be executable. Some targets have a directive to declare this.
991 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
992 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
993 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext))
994 OutStreamer.SwitchSection(S);
996 // Allow the target to emit any magic that it wants at the end of the file,
997 // after everything else has gone out.
1000 delete Mang; Mang = 0;
1003 OutStreamer.Finish();
1004 OutStreamer.reset();
1009 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
1011 // Get the function symbol.
1012 CurrentFnSym = getSymbol(MF.getFunction());
1013 CurrentFnSymForSize = CurrentFnSym;
1016 LI = &getAnalysis<MachineLoopInfo>();
1020 // SectionCPs - Keep track the alignment, constpool entries per Section.
1024 SmallVector<unsigned, 4> CPEs;
1025 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
1029 /// EmitConstantPool - Print to the current output stream assembly
1030 /// representations of the constants in the constant pool MCP. This is
1031 /// used to print out constants which have been "spilled to memory" by
1032 /// the code generator.
1034 void AsmPrinter::EmitConstantPool() {
1035 const MachineConstantPool *MCP = MF->getConstantPool();
1036 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
1037 if (CP.empty()) return;
1039 // Calculate sections for constant pool entries. We collect entries to go into
1040 // the same section together to reduce amount of section switch statements.
1041 SmallVector<SectionCPs, 4> CPSections;
1042 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
1043 const MachineConstantPoolEntry &CPE = CP[i];
1044 unsigned Align = CPE.getAlignment();
1047 switch (CPE.getRelocationInfo()) {
1048 default: llvm_unreachable("Unknown section kind");
1049 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
1051 Kind = SectionKind::getReadOnlyWithRelLocal();
1054 switch (TM.getDataLayout()->getTypeAllocSize(CPE.getType())) {
1055 case 4: Kind = SectionKind::getMergeableConst4(); break;
1056 case 8: Kind = SectionKind::getMergeableConst8(); break;
1057 case 16: Kind = SectionKind::getMergeableConst16();break;
1058 default: Kind = SectionKind::getMergeableConst(); break;
1062 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
1064 // The number of sections are small, just do a linear search from the
1065 // last section to the first.
1067 unsigned SecIdx = CPSections.size();
1068 while (SecIdx != 0) {
1069 if (CPSections[--SecIdx].S == S) {
1075 SecIdx = CPSections.size();
1076 CPSections.push_back(SectionCPs(S, Align));
1079 if (Align > CPSections[SecIdx].Alignment)
1080 CPSections[SecIdx].Alignment = Align;
1081 CPSections[SecIdx].CPEs.push_back(i);
1084 // Now print stuff into the calculated sections.
1085 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
1086 OutStreamer.SwitchSection(CPSections[i].S);
1087 EmitAlignment(Log2_32(CPSections[i].Alignment));
1089 unsigned Offset = 0;
1090 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
1091 unsigned CPI = CPSections[i].CPEs[j];
1092 MachineConstantPoolEntry CPE = CP[CPI];
1094 // Emit inter-object padding for alignment.
1095 unsigned AlignMask = CPE.getAlignment() - 1;
1096 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
1097 OutStreamer.EmitZeros(NewOffset - Offset);
1099 Type *Ty = CPE.getType();
1100 Offset = NewOffset + TM.getDataLayout()->getTypeAllocSize(Ty);
1101 OutStreamer.EmitLabel(GetCPISymbol(CPI));
1103 if (CPE.isMachineConstantPoolEntry())
1104 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
1106 EmitGlobalConstant(CPE.Val.ConstVal);
1111 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
1112 /// by the current function to the current output stream.
1114 void AsmPrinter::EmitJumpTableInfo() {
1115 const DataLayout *DL = MF->getTarget().getDataLayout();
1116 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1117 if (MJTI == 0) return;
1118 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
1119 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1120 if (JT.empty()) return;
1122 // Pick the directive to use to print the jump table entries, and switch to
1123 // the appropriate section.
1124 const Function *F = MF->getFunction();
1125 bool JTInDiffSection = false;
1126 if (// In PIC mode, we need to emit the jump table to the same section as the
1127 // function body itself, otherwise the label differences won't make sense.
1128 // FIXME: Need a better predicate for this: what about custom entries?
1129 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
1130 // We should also do if the section name is NULL or function is declared
1131 // in discardable section
1132 // FIXME: this isn't the right predicate, should be based on the MCSection
1133 // for the function.
1134 F->isWeakForLinker()) {
1135 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
1137 // Otherwise, drop it in the readonly section.
1138 const MCSection *ReadOnlySection =
1139 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
1140 OutStreamer.SwitchSection(ReadOnlySection);
1141 JTInDiffSection = true;
1144 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getDataLayout())));
1146 // Jump tables in code sections are marked with a data_region directive
1147 // where that's supported.
1148 if (!JTInDiffSection)
1149 OutStreamer.EmitDataRegion(MCDR_DataRegionJT32);
1151 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
1152 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1154 // If this jump table was deleted, ignore it.
1155 if (JTBBs.empty()) continue;
1157 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
1158 // .set directive for each unique entry. This reduces the number of
1159 // relocations the assembler will generate for the jump table.
1160 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
1161 MAI->hasSetDirective()) {
1162 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
1163 const TargetLowering *TLI = TM.getTargetLowering();
1164 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
1165 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
1166 const MachineBasicBlock *MBB = JTBBs[ii];
1167 if (!EmittedSets.insert(MBB)) continue;
1169 // .set LJTSet, LBB32-base
1171 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1172 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
1173 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
1177 // On some targets (e.g. Darwin) we want to emit two consecutive labels
1178 // before each jump table. The first label is never referenced, but tells
1179 // the assembler and linker the extents of the jump table object. The
1180 // second label is actually referenced by the code.
1181 if (JTInDiffSection && DL->hasLinkerPrivateGlobalPrefix())
1182 // FIXME: This doesn't have to have any specific name, just any randomly
1183 // named and numbered 'l' label would work. Simplify GetJTISymbol.
1184 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
1186 OutStreamer.EmitLabel(GetJTISymbol(JTI));
1188 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
1189 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
1191 if (!JTInDiffSection)
1192 OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
1195 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
1197 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
1198 const MachineBasicBlock *MBB,
1199 unsigned UID) const {
1200 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block");
1201 const MCExpr *Value = 0;
1202 switch (MJTI->getEntryKind()) {
1203 case MachineJumpTableInfo::EK_Inline:
1204 llvm_unreachable("Cannot emit EK_Inline jump table entry");
1205 case MachineJumpTableInfo::EK_Custom32:
1206 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
1209 case MachineJumpTableInfo::EK_BlockAddress:
1210 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
1212 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1214 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
1215 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
1216 // with a relocation as gp-relative, e.g.:
1218 MCSymbol *MBBSym = MBB->getSymbol();
1219 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1223 case MachineJumpTableInfo::EK_GPRel64BlockAddress: {
1224 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded
1225 // with a relocation as gp-relative, e.g.:
1227 MCSymbol *MBBSym = MBB->getSymbol();
1228 OutStreamer.EmitGPRel64Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1232 case MachineJumpTableInfo::EK_LabelDifference32: {
1233 // EK_LabelDifference32 - Each entry is the address of the block minus
1234 // the address of the jump table. This is used for PIC jump tables where
1235 // gprel32 is not supported. e.g.:
1236 // .word LBB123 - LJTI1_2
1237 // If the .set directive is supported, this is emitted as:
1238 // .set L4_5_set_123, LBB123 - LJTI1_2
1239 // .word L4_5_set_123
1241 // If we have emitted set directives for the jump table entries, print
1242 // them rather than the entries themselves. If we're emitting PIC, then
1243 // emit the table entries as differences between two text section labels.
1244 if (MAI->hasSetDirective()) {
1245 // If we used .set, reference the .set's symbol.
1246 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
1250 // Otherwise, use the difference as the jump table entry.
1251 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1252 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
1253 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
1258 assert(Value && "Unknown entry kind!");
1260 unsigned EntrySize = MJTI->getEntrySize(*TM.getDataLayout());
1261 OutStreamer.EmitValue(Value, EntrySize);
1265 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
1266 /// special global used by LLVM. If so, emit it and return true, otherwise
1267 /// do nothing and return false.
1268 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
1269 if (GV->getName() == "llvm.used") {
1270 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
1271 EmitLLVMUsedList(cast<ConstantArray>(GV->getInitializer()));
1275 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
1276 if (GV->getSection() == "llvm.metadata" ||
1277 GV->hasAvailableExternallyLinkage())
1280 if (!GV->hasAppendingLinkage()) return false;
1282 assert(GV->hasInitializer() && "Not a special LLVM global!");
1284 if (GV->getName() == "llvm.global_ctors") {
1285 EmitXXStructorList(GV->getInitializer(), /* isCtor */ true);
1287 if (TM.getRelocationModel() == Reloc::Static &&
1288 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1289 StringRef Sym(".constructors_used");
1290 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1296 if (GV->getName() == "llvm.global_dtors") {
1297 EmitXXStructorList(GV->getInitializer(), /* isCtor */ false);
1299 if (TM.getRelocationModel() == Reloc::Static &&
1300 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1301 StringRef Sym(".destructors_used");
1302 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1311 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1312 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1313 /// is true, as being used with this directive.
1314 void AsmPrinter::EmitLLVMUsedList(const ConstantArray *InitList) {
1315 // Should be an array of 'i8*'.
1316 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1317 const GlobalValue *GV =
1318 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1319 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
1320 OutStreamer.EmitSymbolAttribute(getSymbol(GV), MCSA_NoDeadStrip);
1324 /// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
1326 void AsmPrinter::EmitXXStructorList(const Constant *List, bool isCtor) {
1327 // Should be an array of '{ int, void ()* }' structs. The first value is the
1329 if (!isa<ConstantArray>(List)) return;
1331 // Sanity check the structors list.
1332 const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1333 if (!InitList) return; // Not an array!
1334 StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType());
1335 if (!ETy || ETy->getNumElements() != 2) return; // Not an array of pairs!
1336 if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) ||
1337 !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr).
1339 // Gather the structors in a form that's convenient for sorting by priority.
1340 typedef std::pair<unsigned, Constant *> Structor;
1341 SmallVector<Structor, 8> Structors;
1342 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1343 ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i));
1344 if (!CS) continue; // Malformed.
1345 if (CS->getOperand(1)->isNullValue())
1346 break; // Found a null terminator, skip the rest.
1347 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
1348 if (!Priority) continue; // Malformed.
1349 Structors.push_back(std::make_pair(Priority->getLimitedValue(65535),
1350 CS->getOperand(1)));
1353 // Emit the function pointers in the target-specific order
1354 const DataLayout *DL = TM.getDataLayout();
1355 unsigned Align = Log2_32(DL->getPointerPrefAlignment());
1356 std::stable_sort(Structors.begin(), Structors.end(), less_first());
1357 for (unsigned i = 0, e = Structors.size(); i != e; ++i) {
1358 const MCSection *OutputSection =
1360 getObjFileLowering().getStaticCtorSection(Structors[i].first) :
1361 getObjFileLowering().getStaticDtorSection(Structors[i].first));
1362 OutStreamer.SwitchSection(OutputSection);
1363 if (OutStreamer.getCurrentSection() != OutStreamer.getPreviousSection())
1364 EmitAlignment(Align);
1365 EmitXXStructor(Structors[i].second);
1369 void AsmPrinter::EmitModuleIdents(Module &M) {
1370 if (!MAI->hasIdentDirective())
1373 if (const NamedMDNode *NMD = M.getNamedMetadata("llvm.ident")) {
1374 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
1375 const MDNode *N = NMD->getOperand(i);
1376 assert(N->getNumOperands() == 1 &&
1377 "llvm.ident metadata entry can have only one operand");
1378 const MDString *S = cast<MDString>(N->getOperand(0));
1379 OutStreamer.EmitIdent(S->getString());
1384 //===--------------------------------------------------------------------===//
1385 // Emission and print routines
1388 /// EmitInt8 - Emit a byte directive and value.
1390 void AsmPrinter::EmitInt8(int Value) const {
1391 OutStreamer.EmitIntValue(Value, 1);
1394 /// EmitInt16 - Emit a short directive and value.
1396 void AsmPrinter::EmitInt16(int Value) const {
1397 OutStreamer.EmitIntValue(Value, 2);
1400 /// EmitInt32 - Emit a long directive and value.
1402 void AsmPrinter::EmitInt32(int Value) const {
1403 OutStreamer.EmitIntValue(Value, 4);
1406 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
1407 /// in bytes of the directive is specified by Size and Hi/Lo specify the
1408 /// labels. This implicitly uses .set if it is available.
1409 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1410 unsigned Size) const {
1411 // Get the Hi-Lo expression.
1412 const MCExpr *Diff =
1413 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1414 MCSymbolRefExpr::Create(Lo, OutContext),
1417 if (!MAI->hasSetDirective()) {
1418 OutStreamer.EmitValue(Diff, Size);
1422 // Otherwise, emit with .set (aka assignment).
1423 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1424 OutStreamer.EmitAssignment(SetLabel, Diff);
1425 OutStreamer.EmitSymbolValue(SetLabel, Size);
1428 /// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo"
1429 /// where the size in bytes of the directive is specified by Size and Hi/Lo
1430 /// specify the labels. This implicitly uses .set if it is available.
1431 void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset,
1433 unsigned Size) const {
1435 // Emit Hi+Offset - Lo
1436 // Get the Hi+Offset expression.
1437 const MCExpr *Plus =
1438 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext),
1439 MCConstantExpr::Create(Offset, OutContext),
1442 // Get the Hi+Offset-Lo expression.
1443 const MCExpr *Diff =
1444 MCBinaryExpr::CreateSub(Plus,
1445 MCSymbolRefExpr::Create(Lo, OutContext),
1448 if (!MAI->hasSetDirective())
1449 OutStreamer.EmitValue(Diff, Size);
1451 // Otherwise, emit with .set (aka assignment).
1452 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1453 OutStreamer.EmitAssignment(SetLabel, Diff);
1454 OutStreamer.EmitSymbolValue(SetLabel, Size);
1458 /// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
1459 /// where the size in bytes of the directive is specified by Size and Label
1460 /// specifies the label. This implicitly uses .set if it is available.
1461 void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset,
1463 bool IsSectionRelative) const {
1464 if (MAI->needsDwarfSectionOffsetDirective() && IsSectionRelative) {
1465 OutStreamer.EmitCOFFSecRel32(Label);
1469 // Emit Label+Offset (or just Label if Offset is zero)
1470 const MCExpr *Expr = MCSymbolRefExpr::Create(Label, OutContext);
1472 Expr = MCBinaryExpr::CreateAdd(
1473 Expr, MCConstantExpr::Create(Offset, OutContext), OutContext);
1475 OutStreamer.EmitValue(Expr, Size);
1478 //===----------------------------------------------------------------------===//
1480 // EmitAlignment - Emit an alignment directive to the specified power of
1481 // two boundary. For example, if you pass in 3 here, you will get an 8
1482 // byte alignment. If a global value is specified, and if that global has
1483 // an explicit alignment requested, it will override the alignment request
1484 // if required for correctness.
1486 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV) const {
1487 if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getDataLayout(), NumBits);
1489 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.
1491 if (getCurrentSection()->getKind().isText())
1492 OutStreamer.EmitCodeAlignment(1 << NumBits);
1494 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
1497 //===----------------------------------------------------------------------===//
1498 // Constant emission.
1499 //===----------------------------------------------------------------------===//
1501 /// lowerConstant - Lower the specified LLVM Constant to an MCExpr.
1503 static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP) {
1504 MCContext &Ctx = AP.OutContext;
1506 if (CV->isNullValue() || isa<UndefValue>(CV))
1507 return MCConstantExpr::Create(0, Ctx);
1509 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1510 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1512 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1513 return MCSymbolRefExpr::Create(AP.getSymbol(GV), Ctx);
1515 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1516 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1518 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1520 llvm_unreachable("Unknown constant value to lower!");
1523 if (const MCExpr *RelocExpr =
1524 AP.getObjFileLowering().getExecutableRelativeSymbol(CE, AP.Mang))
1527 switch (CE->getOpcode()) {
1529 // If the code isn't optimized, there may be outstanding folding
1530 // opportunities. Attempt to fold the expression using DataLayout as a
1531 // last resort before giving up.
1533 ConstantFoldConstantExpression(CE, AP.TM.getDataLayout()))
1535 return lowerConstant(C, AP);
1537 // Otherwise report the problem to the user.
1540 raw_string_ostream OS(S);
1541 OS << "Unsupported expression in static initializer: ";
1542 CE->printAsOperand(OS, /*PrintType=*/false,
1543 !AP.MF ? 0 : AP.MF->getFunction()->getParent());
1544 report_fatal_error(OS.str());
1546 case Instruction::GetElementPtr: {
1547 const DataLayout &DL = *AP.TM.getDataLayout();
1548 // Generate a symbolic expression for the byte address
1549 APInt OffsetAI(DL.getPointerTypeSizeInBits(CE->getType()), 0);
1550 cast<GEPOperator>(CE)->accumulateConstantOffset(DL, OffsetAI);
1552 const MCExpr *Base = lowerConstant(CE->getOperand(0), AP);
1556 int64_t Offset = OffsetAI.getSExtValue();
1557 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1561 case Instruction::Trunc:
1562 // We emit the value and depend on the assembler to truncate the generated
1563 // expression properly. This is important for differences between
1564 // blockaddress labels. Since the two labels are in the same function, it
1565 // is reasonable to treat their delta as a 32-bit value.
1567 case Instruction::BitCast:
1568 return lowerConstant(CE->getOperand(0), AP);
1570 case Instruction::IntToPtr: {
1571 const DataLayout &DL = *AP.TM.getDataLayout();
1572 // Handle casts to pointers by changing them into casts to the appropriate
1573 // integer type. This promotes constant folding and simplifies this code.
1574 Constant *Op = CE->getOperand(0);
1575 Op = ConstantExpr::getIntegerCast(Op, DL.getIntPtrType(CV->getType()),
1577 return lowerConstant(Op, AP);
1580 case Instruction::PtrToInt: {
1581 const DataLayout &DL = *AP.TM.getDataLayout();
1582 // Support only foldable casts to/from pointers that can be eliminated by
1583 // changing the pointer to the appropriately sized integer type.
1584 Constant *Op = CE->getOperand(0);
1585 Type *Ty = CE->getType();
1587 const MCExpr *OpExpr = lowerConstant(Op, AP);
1589 // We can emit the pointer value into this slot if the slot is an
1590 // integer slot equal to the size of the pointer.
1591 if (DL.getTypeAllocSize(Ty) == DL.getTypeAllocSize(Op->getType()))
1594 // Otherwise the pointer is smaller than the resultant integer, mask off
1595 // the high bits so we are sure to get a proper truncation if the input is
1597 unsigned InBits = DL.getTypeAllocSizeInBits(Op->getType());
1598 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1599 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1602 // The MC library also has a right-shift operator, but it isn't consistently
1603 // signed or unsigned between different targets.
1604 case Instruction::Add:
1605 case Instruction::Sub:
1606 case Instruction::Mul:
1607 case Instruction::SDiv:
1608 case Instruction::SRem:
1609 case Instruction::Shl:
1610 case Instruction::And:
1611 case Instruction::Or:
1612 case Instruction::Xor: {
1613 const MCExpr *LHS = lowerConstant(CE->getOperand(0), AP);
1614 const MCExpr *RHS = lowerConstant(CE->getOperand(1), AP);
1615 switch (CE->getOpcode()) {
1616 default: llvm_unreachable("Unknown binary operator constant cast expr");
1617 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1618 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1619 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1620 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1621 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1622 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1623 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1624 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1625 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1631 static void emitGlobalConstantImpl(const Constant *C, AsmPrinter &AP);
1633 /// isRepeatedByteSequence - Determine whether the given value is
1634 /// composed of a repeated sequence of identical bytes and return the
1635 /// byte value. If it is not a repeated sequence, return -1.
1636 static int isRepeatedByteSequence(const ConstantDataSequential *V) {
1637 StringRef Data = V->getRawDataValues();
1638 assert(!Data.empty() && "Empty aggregates should be CAZ node");
1640 for (unsigned i = 1, e = Data.size(); i != e; ++i)
1641 if (Data[i] != C) return -1;
1642 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1.
1646 /// isRepeatedByteSequence - Determine whether the given value is
1647 /// composed of a repeated sequence of identical bytes and return the
1648 /// byte value. If it is not a repeated sequence, return -1.
1649 static int isRepeatedByteSequence(const Value *V, TargetMachine &TM) {
1651 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
1652 if (CI->getBitWidth() > 64) return -1;
1654 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(V->getType());
1655 uint64_t Value = CI->getZExtValue();
1657 // Make sure the constant is at least 8 bits long and has a power
1658 // of 2 bit width. This guarantees the constant bit width is
1659 // always a multiple of 8 bits, avoiding issues with padding out
1660 // to Size and other such corner cases.
1661 if (CI->getBitWidth() < 8 || !isPowerOf2_64(CI->getBitWidth())) return -1;
1663 uint8_t Byte = static_cast<uint8_t>(Value);
1665 for (unsigned i = 1; i < Size; ++i) {
1667 if (static_cast<uint8_t>(Value) != Byte) return -1;
1671 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) {
1672 // Make sure all array elements are sequences of the same repeated
1674 assert(CA->getNumOperands() != 0 && "Should be a CAZ");
1675 int Byte = isRepeatedByteSequence(CA->getOperand(0), TM);
1676 if (Byte == -1) return -1;
1678 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i) {
1679 int ThisByte = isRepeatedByteSequence(CA->getOperand(i), TM);
1680 if (ThisByte == -1) return -1;
1681 if (Byte != ThisByte) return -1;
1686 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V))
1687 return isRepeatedByteSequence(CDS);
1692 static void emitGlobalConstantDataSequential(const ConstantDataSequential *CDS,
1695 // See if we can aggregate this into a .fill, if so, emit it as such.
1696 int Value = isRepeatedByteSequence(CDS, AP.TM);
1698 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CDS->getType());
1699 // Don't emit a 1-byte object as a .fill.
1701 return AP.OutStreamer.EmitFill(Bytes, Value);
1704 // If this can be emitted with .ascii/.asciz, emit it as such.
1705 if (CDS->isString())
1706 return AP.OutStreamer.EmitBytes(CDS->getAsString());
1708 // Otherwise, emit the values in successive locations.
1709 unsigned ElementByteSize = CDS->getElementByteSize();
1710 if (isa<IntegerType>(CDS->getElementType())) {
1711 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1713 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1714 CDS->getElementAsInteger(i));
1715 AP.OutStreamer.EmitIntValue(CDS->getElementAsInteger(i),
1718 } else if (ElementByteSize == 4) {
1719 // FP Constants are printed as integer constants to avoid losing
1721 assert(CDS->getElementType()->isFloatTy());
1722 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1728 F = CDS->getElementAsFloat(i);
1730 AP.OutStreamer.GetCommentOS() << "float " << F << '\n';
1731 AP.OutStreamer.EmitIntValue(I, 4);
1734 assert(CDS->getElementType()->isDoubleTy());
1735 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1741 F = CDS->getElementAsDouble(i);
1743 AP.OutStreamer.GetCommentOS() << "double " << F << '\n';
1744 AP.OutStreamer.EmitIntValue(I, 8);
1748 const DataLayout &DL = *AP.TM.getDataLayout();
1749 unsigned Size = DL.getTypeAllocSize(CDS->getType());
1750 unsigned EmittedSize = DL.getTypeAllocSize(CDS->getType()->getElementType()) *
1751 CDS->getNumElements();
1752 if (unsigned Padding = Size - EmittedSize)
1753 AP.OutStreamer.EmitZeros(Padding);
1757 static void emitGlobalConstantArray(const ConstantArray *CA, AsmPrinter &AP) {
1758 // See if we can aggregate some values. Make sure it can be
1759 // represented as a series of bytes of the constant value.
1760 int Value = isRepeatedByteSequence(CA, AP.TM);
1763 uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CA->getType());
1764 AP.OutStreamer.EmitFill(Bytes, Value);
1767 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1768 emitGlobalConstantImpl(CA->getOperand(i), AP);
1772 static void emitGlobalConstantVector(const ConstantVector *CV, AsmPrinter &AP) {
1773 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1774 emitGlobalConstantImpl(CV->getOperand(i), AP);
1776 const DataLayout &DL = *AP.TM.getDataLayout();
1777 unsigned Size = DL.getTypeAllocSize(CV->getType());
1778 unsigned EmittedSize = DL.getTypeAllocSize(CV->getType()->getElementType()) *
1779 CV->getType()->getNumElements();
1780 if (unsigned Padding = Size - EmittedSize)
1781 AP.OutStreamer.EmitZeros(Padding);
1784 static void emitGlobalConstantStruct(const ConstantStruct *CS, AsmPrinter &AP) {
1785 // Print the fields in successive locations. Pad to align if needed!
1786 const DataLayout *DL = AP.TM.getDataLayout();
1787 unsigned Size = DL->getTypeAllocSize(CS->getType());
1788 const StructLayout *Layout = DL->getStructLayout(CS->getType());
1789 uint64_t SizeSoFar = 0;
1790 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1791 const Constant *Field = CS->getOperand(i);
1793 // Check if padding is needed and insert one or more 0s.
1794 uint64_t FieldSize = DL->getTypeAllocSize(Field->getType());
1795 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1796 - Layout->getElementOffset(i)) - FieldSize;
1797 SizeSoFar += FieldSize + PadSize;
1799 // Now print the actual field value.
1800 emitGlobalConstantImpl(Field, AP);
1802 // Insert padding - this may include padding to increase the size of the
1803 // current field up to the ABI size (if the struct is not packed) as well
1804 // as padding to ensure that the next field starts at the right offset.
1805 AP.OutStreamer.EmitZeros(PadSize);
1807 assert(SizeSoFar == Layout->getSizeInBytes() &&
1808 "Layout of constant struct may be incorrect!");
1811 static void emitGlobalConstantFP(const ConstantFP *CFP, AsmPrinter &AP) {
1812 APInt API = CFP->getValueAPF().bitcastToAPInt();
1814 // First print a comment with what we think the original floating-point value
1815 // should have been.
1816 if (AP.isVerbose()) {
1817 SmallString<8> StrVal;
1818 CFP->getValueAPF().toString(StrVal);
1820 CFP->getType()->print(AP.OutStreamer.GetCommentOS());
1821 AP.OutStreamer.GetCommentOS() << ' ' << StrVal << '\n';
1824 // Now iterate through the APInt chunks, emitting them in endian-correct
1825 // order, possibly with a smaller chunk at beginning/end (e.g. for x87 80-bit
1827 unsigned NumBytes = API.getBitWidth() / 8;
1828 unsigned TrailingBytes = NumBytes % sizeof(uint64_t);
1829 const uint64_t *p = API.getRawData();
1831 // PPC's long double has odd notions of endianness compared to how LLVM
1832 // handles it: p[0] goes first for *big* endian on PPC.
1833 if (AP.TM.getDataLayout()->isBigEndian() != CFP->getType()->isPPC_FP128Ty()) {
1834 int Chunk = API.getNumWords() - 1;
1837 AP.OutStreamer.EmitIntValue(p[Chunk--], TrailingBytes);
1839 for (; Chunk >= 0; --Chunk)
1840 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1843 for (Chunk = 0; Chunk < NumBytes / sizeof(uint64_t); ++Chunk)
1844 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1847 AP.OutStreamer.EmitIntValue(p[Chunk], TrailingBytes);
1850 // Emit the tail padding for the long double.
1851 const DataLayout &DL = *AP.TM.getDataLayout();
1852 AP.OutStreamer.EmitZeros(DL.getTypeAllocSize(CFP->getType()) -
1853 DL.getTypeStoreSize(CFP->getType()));
1856 static void emitGlobalConstantLargeInt(const ConstantInt *CI, AsmPrinter &AP) {
1857 const DataLayout *DL = AP.TM.getDataLayout();
1858 unsigned BitWidth = CI->getBitWidth();
1860 // Copy the value as we may massage the layout for constants whose bit width
1861 // is not a multiple of 64-bits.
1862 APInt Realigned(CI->getValue());
1863 uint64_t ExtraBits = 0;
1864 unsigned ExtraBitsSize = BitWidth & 63;
1866 if (ExtraBitsSize) {
1867 // The bit width of the data is not a multiple of 64-bits.
1868 // The extra bits are expected to be at the end of the chunk of the memory.
1870 // * Nothing to be done, just record the extra bits to emit.
1872 // * Record the extra bits to emit.
1873 // * Realign the raw data to emit the chunks of 64-bits.
1874 if (DL->isBigEndian()) {
1875 // Basically the structure of the raw data is a chunk of 64-bits cells:
1876 // 0 1 BitWidth / 64
1877 // [chunk1][chunk2] ... [chunkN].
1878 // The most significant chunk is chunkN and it should be emitted first.
1879 // However, due to the alignment issue chunkN contains useless bits.
1880 // Realign the chunks so that they contain only useless information:
1881 // ExtraBits 0 1 (BitWidth / 64) - 1
1882 // chu[nk1 chu][nk2 chu] ... [nkN-1 chunkN]
1883 ExtraBits = Realigned.getRawData()[0] &
1884 (((uint64_t)-1) >> (64 - ExtraBitsSize));
1885 Realigned = Realigned.lshr(ExtraBitsSize);
1887 ExtraBits = Realigned.getRawData()[BitWidth / 64];
1890 // We don't expect assemblers to support integer data directives
1891 // for more than 64 bits, so we emit the data in at most 64-bit
1892 // quantities at a time.
1893 const uint64_t *RawData = Realigned.getRawData();
1894 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1895 uint64_t Val = DL->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1896 AP.OutStreamer.EmitIntValue(Val, 8);
1899 if (ExtraBitsSize) {
1900 // Emit the extra bits after the 64-bits chunks.
1902 // Emit a directive that fills the expected size.
1903 uint64_t Size = AP.TM.getDataLayout()->getTypeAllocSize(CI->getType());
1904 Size -= (BitWidth / 64) * 8;
1905 assert(Size && Size * 8 >= ExtraBitsSize &&
1906 (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize)))
1907 == ExtraBits && "Directive too small for extra bits.");
1908 AP.OutStreamer.EmitIntValue(ExtraBits, Size);
1912 static void emitGlobalConstantImpl(const Constant *CV, AsmPrinter &AP) {
1913 const DataLayout *DL = AP.TM.getDataLayout();
1914 uint64_t Size = DL->getTypeAllocSize(CV->getType());
1915 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV))
1916 return AP.OutStreamer.EmitZeros(Size);
1918 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1925 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1926 CI->getZExtValue());
1927 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size);
1930 emitGlobalConstantLargeInt(CI, AP);
1935 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1936 return emitGlobalConstantFP(CFP, AP);
1938 if (isa<ConstantPointerNull>(CV)) {
1939 AP.OutStreamer.EmitIntValue(0, Size);
1943 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV))
1944 return emitGlobalConstantDataSequential(CDS, AP);
1946 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1947 return emitGlobalConstantArray(CVA, AP);
1949 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1950 return emitGlobalConstantStruct(CVS, AP);
1952 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
1953 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
1955 if (CE->getOpcode() == Instruction::BitCast)
1956 return emitGlobalConstantImpl(CE->getOperand(0), AP);
1959 // If the constant expression's size is greater than 64-bits, then we have
1960 // to emit the value in chunks. Try to constant fold the value and emit it
1962 Constant *New = ConstantFoldConstantExpression(CE, DL);
1963 if (New && New != CE)
1964 return emitGlobalConstantImpl(New, AP);
1968 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1969 return emitGlobalConstantVector(V, AP);
1971 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1972 // thread the streamer with EmitValue.
1973 AP.OutStreamer.EmitValue(lowerConstant(CV, AP), Size);
1976 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1977 void AsmPrinter::EmitGlobalConstant(const Constant *CV) {
1978 uint64_t Size = TM.getDataLayout()->getTypeAllocSize(CV->getType());
1980 emitGlobalConstantImpl(CV, *this);
1981 else if (MAI->hasSubsectionsViaSymbols()) {
1982 // If the global has zero size, emit a single byte so that two labels don't
1983 // look like they are at the same location.
1984 OutStreamer.EmitIntValue(0, 1);
1988 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1989 // Target doesn't support this yet!
1990 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1993 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1995 OS << '+' << Offset;
1996 else if (Offset < 0)
2000 //===----------------------------------------------------------------------===//
2001 // Symbol Lowering Routines.
2002 //===----------------------------------------------------------------------===//
2004 /// GetTempSymbol - Return the MCSymbol corresponding to the assembler
2005 /// temporary label with the specified stem and unique ID.
2006 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const {
2007 const DataLayout *DL = TM.getDataLayout();
2008 return OutContext.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix()) +
2012 /// GetTempSymbol - Return an assembler temporary label with the specified
2014 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const {
2015 const DataLayout *DL = TM.getDataLayout();
2016 return OutContext.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix())+
2021 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
2022 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
2025 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
2026 return MMI->getAddrLabelSymbol(BB);
2029 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
2030 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
2031 const DataLayout *DL = TM.getDataLayout();
2032 return OutContext.GetOrCreateSymbol
2033 (Twine(DL->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
2034 + "_" + Twine(CPID));
2037 /// GetJTISymbol - Return the symbol for the specified jump table entry.
2038 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
2039 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
2042 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
2043 /// FIXME: privatize to AsmPrinter.
2044 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
2045 const DataLayout *DL = TM.getDataLayout();
2046 return OutContext.GetOrCreateSymbol
2047 (Twine(DL->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
2048 Twine(UID) + "_set_" + Twine(MBBID));
2051 MCSymbol *AsmPrinter::getSymbolWithGlobalValueBase(const GlobalValue *GV,
2052 StringRef Suffix) const {
2053 return getObjFileLowering().getSymbolWithGlobalValueBase(*Mang, GV, Suffix);
2056 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
2058 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
2059 SmallString<60> NameStr;
2060 Mang->getNameWithPrefix(NameStr, Sym);
2061 return OutContext.GetOrCreateSymbol(NameStr.str());
2066 /// PrintParentLoopComment - Print comments about parent loops of this one.
2067 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2068 unsigned FunctionNumber) {
2069 if (Loop == 0) return;
2070 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
2071 OS.indent(Loop->getLoopDepth()*2)
2072 << "Parent Loop BB" << FunctionNumber << "_"
2073 << Loop->getHeader()->getNumber()
2074 << " Depth=" << Loop->getLoopDepth() << '\n';
2078 /// PrintChildLoopComment - Print comments about child loops within
2079 /// the loop for this basic block, with nesting.
2080 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2081 unsigned FunctionNumber) {
2082 // Add child loop information
2083 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
2084 OS.indent((*CL)->getLoopDepth()*2)
2085 << "Child Loop BB" << FunctionNumber << "_"
2086 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
2088 PrintChildLoopComment(OS, *CL, FunctionNumber);
2092 /// emitBasicBlockLoopComments - Pretty-print comments for basic blocks.
2093 static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
2094 const MachineLoopInfo *LI,
2095 const AsmPrinter &AP) {
2096 // Add loop depth information
2097 const MachineLoop *Loop = LI->getLoopFor(&MBB);
2098 if (Loop == 0) return;
2100 MachineBasicBlock *Header = Loop->getHeader();
2101 assert(Header && "No header for loop");
2103 // If this block is not a loop header, just print out what is the loop header
2105 if (Header != &MBB) {
2106 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
2107 Twine(AP.getFunctionNumber())+"_" +
2108 Twine(Loop->getHeader()->getNumber())+
2109 " Depth="+Twine(Loop->getLoopDepth()));
2113 // Otherwise, it is a loop header. Print out information about child and
2115 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
2117 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
2120 OS.indent(Loop->getLoopDepth()*2-2);
2125 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
2127 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
2131 /// EmitBasicBlockStart - This method prints the label for the specified
2132 /// MachineBasicBlock, an alignment (if present) and a comment describing
2133 /// it if appropriate.
2134 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
2135 // Emit an alignment directive for this block, if needed.
2136 if (unsigned Align = MBB->getAlignment())
2137 EmitAlignment(Align);
2139 // If the block has its address taken, emit any labels that were used to
2140 // reference the block. It is possible that there is more than one label
2141 // here, because multiple LLVM BB's may have been RAUW'd to this block after
2142 // the references were generated.
2143 if (MBB->hasAddressTaken()) {
2144 const BasicBlock *BB = MBB->getBasicBlock();
2146 OutStreamer.AddComment("Block address taken");
2148 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
2150 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
2151 OutStreamer.EmitLabel(Syms[i]);
2154 // Print some verbose block comments.
2156 if (const BasicBlock *BB = MBB->getBasicBlock())
2158 OutStreamer.AddComment("%" + BB->getName());
2159 emitBasicBlockLoopComments(*MBB, LI, *this);
2162 // Print the main label for the block.
2163 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
2164 if (isVerbose() && OutStreamer.hasRawTextSupport()) {
2165 // NOTE: Want this comment at start of line, don't emit with AddComment.
2166 OutStreamer.emitRawComment(" BB#" + Twine(MBB->getNumber()) + ":", false);
2169 OutStreamer.EmitLabel(MBB->getSymbol());
2173 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility,
2174 bool IsDefinition) const {
2175 MCSymbolAttr Attr = MCSA_Invalid;
2177 switch (Visibility) {
2179 case GlobalValue::HiddenVisibility:
2181 Attr = MAI->getHiddenVisibilityAttr();
2183 Attr = MAI->getHiddenDeclarationVisibilityAttr();
2185 case GlobalValue::ProtectedVisibility:
2186 Attr = MAI->getProtectedVisibilityAttr();
2190 if (Attr != MCSA_Invalid)
2191 OutStreamer.EmitSymbolAttribute(Sym, Attr);
2194 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
2195 /// exactly one predecessor and the control transfer mechanism between
2196 /// the predecessor and this block is a fall-through.
2198 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
2199 // If this is a landing pad, it isn't a fall through. If it has no preds,
2200 // then nothing falls through to it.
2201 if (MBB->isLandingPad() || MBB->pred_empty())
2204 // If there isn't exactly one predecessor, it can't be a fall through.
2205 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
2207 if (PI2 != MBB->pred_end())
2210 // The predecessor has to be immediately before this block.
2211 MachineBasicBlock *Pred = *PI;
2213 if (!Pred->isLayoutSuccessor(MBB))
2216 // If the block is completely empty, then it definitely does fall through.
2220 // Check the terminators in the previous blocks
2221 for (MachineBasicBlock::iterator II = Pred->getFirstTerminator(),
2222 IE = Pred->end(); II != IE; ++II) {
2223 MachineInstr &MI = *II;
2225 // If it is not a simple branch, we are in a table somewhere.
2226 if (!MI.isBranch() || MI.isIndirectBranch())
2229 // If we are the operands of one of the branches, this is not a fall
2230 // through. Note that targets with delay slots will usually bundle
2231 // terminators with the delay slot instruction.
2232 for (ConstMIBundleOperands OP(&MI); OP.isValid(); ++OP) {
2235 if (OP->isMBB() && OP->getMBB() == MBB)
2245 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
2246 if (!S->usesMetadata())
2249 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
2250 gcp_map_type::iterator GCPI = GCMap.find(S);
2251 if (GCPI != GCMap.end())
2252 return GCPI->second;
2254 const char *Name = S->getName().c_str();
2256 for (GCMetadataPrinterRegistry::iterator
2257 I = GCMetadataPrinterRegistry::begin(),
2258 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
2259 if (strcmp(Name, I->getName()) == 0) {
2260 GCMetadataPrinter *GMP = I->instantiate();
2262 GCMap.insert(std::make_pair(S, GMP));
2266 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));
2269 /// Pin vtable to this file.
2270 AsmPrinterHandler::~AsmPrinterHandler() {}