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/Module.h"
19 #include "llvm/CodeGen/GCMetadataPrinter.h"
20 #include "llvm/CodeGen/MachineConstantPool.h"
21 #include "llvm/CodeGen/MachineFrameInfo.h"
22 #include "llvm/CodeGen/MachineFunction.h"
23 #include "llvm/CodeGen/MachineJumpTableInfo.h"
24 #include "llvm/CodeGen/MachineLoopInfo.h"
25 #include "llvm/CodeGen/MachineModuleInfo.h"
26 #include "llvm/Analysis/ConstantFolding.h"
27 #include "llvm/Analysis/DebugInfo.h"
28 #include "llvm/MC/MCAsmInfo.h"
29 #include "llvm/MC/MCContext.h"
30 #include "llvm/MC/MCExpr.h"
31 #include "llvm/MC/MCInst.h"
32 #include "llvm/MC/MCSection.h"
33 #include "llvm/MC/MCStreamer.h"
34 #include "llvm/MC/MCSymbol.h"
35 #include "llvm/Target/Mangler.h"
36 #include "llvm/Target/TargetData.h"
37 #include "llvm/Target/TargetInstrInfo.h"
38 #include "llvm/Target/TargetLowering.h"
39 #include "llvm/Target/TargetLoweringObjectFile.h"
40 #include "llvm/Target/TargetRegisterInfo.h"
41 #include "llvm/ADT/SmallString.h"
42 #include "llvm/ADT/Statistic.h"
43 #include "llvm/Support/ErrorHandling.h"
44 #include "llvm/Support/Format.h"
45 #include "llvm/Support/Timer.h"
48 static const char *DWARFGroupName = "DWARF Emission";
49 static const char *DbgTimerName = "DWARF Debug Writer";
50 static const char *EHTimerName = "DWARF Exception Writer";
52 STATISTIC(EmittedInsts, "Number of machine instrs printed");
54 char AsmPrinter::ID = 0;
56 typedef DenseMap<GCStrategy*,GCMetadataPrinter*> gcp_map_type;
57 static gcp_map_type &getGCMap(void *&P) {
59 P = new gcp_map_type();
60 return *(gcp_map_type*)P;
64 /// getGVAlignmentLog2 - Return the alignment to use for the specified global
65 /// value in log2 form. This rounds up to the preferred alignment if possible
67 static unsigned getGVAlignmentLog2(const GlobalValue *GV, const TargetData &TD,
68 unsigned InBits = 0) {
70 if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV))
71 NumBits = TD.getPreferredAlignmentLog(GVar);
73 // If InBits is specified, round it to it.
77 // If the GV has a specified alignment, take it into account.
78 if (GV->getAlignment() == 0)
81 unsigned GVAlign = Log2_32(GV->getAlignment());
83 // If the GVAlign is larger than NumBits, or if we are required to obey
84 // NumBits because the GV has an assigned section, obey it.
85 if (GVAlign > NumBits || GV->hasSection())
93 AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
94 : MachineFunctionPass(&ID),
95 TM(tm), MAI(tm.getMCAsmInfo()),
96 OutContext(Streamer.getContext()),
97 OutStreamer(Streamer),
98 LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {
99 DD = 0; DE = 0; MMI = 0; LI = 0;
100 GCMetadataPrinters = 0;
101 VerboseAsm = Streamer.isVerboseAsm();
104 AsmPrinter::~AsmPrinter() {
105 assert(DD == 0 && DE == 0 && "Debug/EH info didn't get finalized");
107 if (GCMetadataPrinters != 0) {
108 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
110 for (gcp_map_type::iterator I = GCMap.begin(), E = GCMap.end(); I != E; ++I)
113 GCMetadataPrinters = 0;
119 /// getFunctionNumber - Return a unique ID for the current function.
121 unsigned AsmPrinter::getFunctionNumber() const {
122 return MF->getFunctionNumber();
125 const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
126 return TM.getTargetLowering()->getObjFileLowering();
130 /// getTargetData - Return information about data layout.
131 const TargetData &AsmPrinter::getTargetData() const {
132 return *TM.getTargetData();
135 /// getCurrentSection() - Return the current section we are emitting to.
136 const MCSection *AsmPrinter::getCurrentSection() const {
137 return OutStreamer.getCurrentSection();
142 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
143 AU.setPreservesAll();
144 MachineFunctionPass::getAnalysisUsage(AU);
145 AU.addRequired<MachineModuleInfo>();
146 AU.addRequired<GCModuleInfo>();
148 AU.addRequired<MachineLoopInfo>();
151 bool AsmPrinter::doInitialization(Module &M) {
152 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
153 MMI->AnalyzeModule(M);
155 // Initialize TargetLoweringObjectFile.
156 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
157 .Initialize(OutContext, TM);
159 Mang = new Mangler(OutContext, *TM.getTargetData());
161 // Allow the target to emit any magic that it wants at the start of the file.
162 EmitStartOfAsmFile(M);
164 // Very minimal debug info. It is ignored if we emit actual debug info. If we
165 // don't, this at least helps the user find where a global came from.
166 if (MAI->hasSingleParameterDotFile()) {
168 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
171 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
172 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
173 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
174 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
175 MP->beginAssembly(*this);
177 // Emit module-level inline asm if it exists.
178 if (!M.getModuleInlineAsm().empty()) {
179 OutStreamer.AddComment("Start of file scope inline assembly");
180 OutStreamer.AddBlankLine();
181 EmitInlineAsm(M.getModuleInlineAsm(), 0/*no loc cookie*/);
182 OutStreamer.AddComment("End of file scope inline assembly");
183 OutStreamer.AddBlankLine();
186 if (MAI->doesSupportDebugInformation())
187 DD = new DwarfDebug(this, &M);
189 if (MAI->doesSupportExceptionHandling())
190 DE = new DwarfException(this);
195 void AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const {
196 switch ((GlobalValue::LinkageTypes)Linkage) {
197 case GlobalValue::CommonLinkage:
198 case GlobalValue::LinkOnceAnyLinkage:
199 case GlobalValue::LinkOnceODRLinkage:
200 case GlobalValue::WeakAnyLinkage:
201 case GlobalValue::WeakODRLinkage:
202 case GlobalValue::LinkerPrivateLinkage:
203 if (MAI->getWeakDefDirective() != 0) {
205 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
206 // .weak_definition _foo
207 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
208 } else if (const char *LinkOnce = MAI->getLinkOnceDirective()) {
210 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
211 //NOTE: linkonce is handling by the section the symbol was assigned to
214 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
217 case GlobalValue::DLLExportLinkage:
218 case GlobalValue::AppendingLinkage:
219 // FIXME: appending linkage variables should go into a section of
220 // their name or something. For now, just emit them as external.
221 case GlobalValue::ExternalLinkage:
222 // If external or appending, declare as a global symbol.
224 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
226 case GlobalValue::PrivateLinkage:
227 case GlobalValue::InternalLinkage:
230 llvm_unreachable("Unknown linkage type!");
235 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
236 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
237 if (!GV->hasInitializer()) // External globals require no code.
240 // Check to see if this is a special global used by LLVM, if so, emit it.
241 if (EmitSpecialLLVMGlobal(GV))
244 MCSymbol *GVSym = Mang->getSymbol(GV);
245 EmitVisibility(GVSym, GV->getVisibility());
247 if (MAI->hasDotTypeDotSizeDirective())
248 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
250 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
252 const TargetData *TD = TM.getTargetData();
253 uint64_t Size = TD->getTypeAllocSize(GV->getType()->getElementType());
255 // If the alignment is specified, we *must* obey it. Overaligning a global
256 // with a specified alignment is a prompt way to break globals emitted to
257 // sections and expected to be contiguous (e.g. ObjC metadata).
258 unsigned AlignLog = getGVAlignmentLog2(GV, *TD);
260 // Handle common and BSS local symbols (.lcomm).
261 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
262 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
265 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
266 /*PrintType=*/false, GV->getParent());
267 OutStreamer.GetCommentOS() << '\n';
270 // Handle common symbols.
271 if (GVKind.isCommon()) {
273 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
277 // Handle local BSS symbols.
278 if (MAI->hasMachoZeroFillDirective()) {
279 const MCSection *TheSection =
280 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
281 // .zerofill __DATA, __bss, _foo, 400, 5
282 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
286 if (MAI->hasLCOMMDirective()) {
288 OutStreamer.EmitLocalCommonSymbol(GVSym, Size);
293 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
295 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
299 const MCSection *TheSection =
300 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
302 // Handle the zerofill directive on darwin, which is a special form of BSS
304 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
305 if (Size == 0) Size = 1; // zerofill of 0 bytes is undefined.
308 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
309 // .zerofill __DATA, __common, _foo, 400, 5
310 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
314 OutStreamer.SwitchSection(TheSection);
316 EmitLinkage(GV->getLinkage(), GVSym);
317 EmitAlignment(AlignLog, GV);
320 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
321 /*PrintType=*/false, GV->getParent());
322 OutStreamer.GetCommentOS() << '\n';
324 OutStreamer.EmitLabel(GVSym);
326 EmitGlobalConstant(GV->getInitializer());
328 if (MAI->hasDotTypeDotSizeDirective())
330 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
332 OutStreamer.AddBlankLine();
335 /// EmitFunctionHeader - This method emits the header for the current
337 void AsmPrinter::EmitFunctionHeader() {
338 // Print out constants referenced by the function
341 // Print the 'header' of function.
342 const Function *F = MF->getFunction();
344 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
345 EmitVisibility(CurrentFnSym, F->getVisibility());
347 EmitLinkage(F->getLinkage(), CurrentFnSym);
348 EmitAlignment(MF->getAlignment(), F);
350 if (MAI->hasDotTypeDotSizeDirective())
351 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
354 WriteAsOperand(OutStreamer.GetCommentOS(), F,
355 /*PrintType=*/false, F->getParent());
356 OutStreamer.GetCommentOS() << '\n';
359 // Emit the CurrentFnSym. This is a virtual function to allow targets to
360 // do their wild and crazy things as required.
361 EmitFunctionEntryLabel();
363 // If the function had address-taken blocks that got deleted, then we have
364 // references to the dangling symbols. Emit them at the start of the function
365 // so that we don't get references to undefined symbols.
366 std::vector<MCSymbol*> DeadBlockSyms;
367 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
368 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
369 OutStreamer.AddComment("Address taken block that was later removed");
370 OutStreamer.EmitLabel(DeadBlockSyms[i]);
373 // Add some workaround for linkonce linkage on Cygwin\MinGW.
374 if (MAI->getLinkOnceDirective() != 0 &&
375 (F->hasLinkOnceLinkage() || F->hasWeakLinkage())) {
376 // FIXME: What is this?
378 OutContext.GetOrCreateSymbol(Twine("Lllvm$workaround$fake$stub$")+
379 CurrentFnSym->getName());
380 OutStreamer.EmitLabel(FakeStub);
383 // Emit pre-function debug and/or EH information.
385 if (TimePassesIsEnabled) {
386 NamedRegionTimer T(EHTimerName, DWARFGroupName);
387 DE->BeginFunction(MF);
389 DE->BeginFunction(MF);
393 if (TimePassesIsEnabled) {
394 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
395 DD->beginFunction(MF);
397 DD->beginFunction(MF);
402 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
403 /// function. This can be overridden by targets as required to do custom stuff.
404 void AsmPrinter::EmitFunctionEntryLabel() {
405 // The function label could have already been emitted if two symbols end up
406 // conflicting due to asm renaming. Detect this and emit an error.
407 if (CurrentFnSym->isUndefined())
408 return OutStreamer.EmitLabel(CurrentFnSym);
410 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
411 "' label emitted multiple times to assembly file");
415 /// EmitComments - Pretty-print comments for instructions.
416 static void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
417 const MachineFunction *MF = MI.getParent()->getParent();
418 const TargetMachine &TM = MF->getTarget();
420 DebugLoc DL = MI.getDebugLoc();
421 if (!DL.isUnknown()) { // Print source line info.
422 DIScope Scope(DL.getScope(MF->getFunction()->getContext()));
423 // Omit the directory, because it's likely to be long and uninteresting.
425 CommentOS << Scope.getFilename();
427 CommentOS << "<unknown>";
428 CommentOS << ':' << DL.getLine();
429 if (DL.getCol() != 0)
430 CommentOS << ':' << DL.getCol();
434 // Check for spills and reloads
437 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
439 // We assume a single instruction only has a spill or reload, not
441 const MachineMemOperand *MMO;
442 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
443 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
444 MMO = *MI.memoperands_begin();
445 CommentOS << MMO->getSize() << "-byte Reload\n";
447 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
448 if (FrameInfo->isSpillSlotObjectIndex(FI))
449 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
450 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
451 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
452 MMO = *MI.memoperands_begin();
453 CommentOS << MMO->getSize() << "-byte Spill\n";
455 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
456 if (FrameInfo->isSpillSlotObjectIndex(FI))
457 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
460 // Check for spill-induced copies
461 unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
462 if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg,
463 SrcSubIdx, DstSubIdx)) {
464 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
465 CommentOS << " Reload Reuse\n";
469 /// EmitImplicitDef - This method emits the specified machine instruction
470 /// that is an implicit def.
471 static void EmitImplicitDef(const MachineInstr *MI, AsmPrinter &AP) {
472 unsigned RegNo = MI->getOperand(0).getReg();
473 AP.OutStreamer.AddComment(Twine("implicit-def: ") +
474 AP.TM.getRegisterInfo()->getName(RegNo));
475 AP.OutStreamer.AddBlankLine();
478 static void EmitKill(const MachineInstr *MI, AsmPrinter &AP) {
479 std::string Str = "kill:";
480 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
481 const MachineOperand &Op = MI->getOperand(i);
482 assert(Op.isReg() && "KILL instruction must have only register operands");
484 Str += AP.TM.getRegisterInfo()->getName(Op.getReg());
485 Str += (Op.isDef() ? "<def>" : "<kill>");
487 AP.OutStreamer.AddComment(Str);
488 AP.OutStreamer.AddBlankLine();
491 /// EmitDebugValueComment - This method handles the target-independent form
492 /// of DBG_VALUE, returning true if it was able to do so. A false return
493 /// means the target will need to handle MI in EmitInstruction.
494 static bool EmitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
495 // This code handles only the 3-operand target-independent form.
496 if (MI->getNumOperands() != 3)
499 SmallString<128> Str;
500 raw_svector_ostream OS(Str);
501 OS << '\t' << AP.MAI->getCommentString() << "DEBUG_VALUE: ";
503 // cast away const; DIetc do not take const operands for some reason.
504 DIVariable V(const_cast<MDNode*>(MI->getOperand(2).getMetadata()));
505 if (V.getContext().isSubprogram())
506 OS << DISubprogram(V.getContext()).getDisplayName() << ":";
507 OS << V.getName() << " <- ";
509 // Register or immediate value. Register 0 means undef.
510 if (MI->getOperand(0).isFPImm()) {
511 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
512 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
513 OS << (double)APF.convertToFloat();
514 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
515 OS << APF.convertToDouble();
517 // There is no good way to print long double. Convert a copy to
518 // double. Ah well, it's only a comment.
520 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
522 OS << "(long double) " << APF.convertToDouble();
524 } else if (MI->getOperand(0).isImm()) {
525 OS << MI->getOperand(0).getImm();
527 assert(MI->getOperand(0).isReg() && "Unknown operand type");
528 if (MI->getOperand(0).getReg() == 0) {
529 // Suppress offset, it is not meaningful here.
531 // NOTE: Want this comment at start of line, don't emit with AddComment.
532 AP.OutStreamer.EmitRawText(OS.str());
535 OS << AP.TM.getRegisterInfo()->getName(MI->getOperand(0).getReg());
538 OS << '+' << MI->getOperand(1).getImm();
539 // NOTE: Want this comment at start of line, don't emit with AddComment.
540 AP.OutStreamer.EmitRawText(OS.str());
544 /// EmitFunctionBody - This method emits the body and trailer for a
546 void AsmPrinter::EmitFunctionBody() {
547 // Emit target-specific gunk before the function body.
548 EmitFunctionBodyStart();
550 bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo();
552 // Print out code for the function.
553 bool HasAnyRealCode = false;
554 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
556 // Print a label for the basic block.
557 EmitBasicBlockStart(I);
558 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
560 // Print the assembly for the instruction.
561 if (!II->isLabel() && !II->isImplicitDef() && !II->isKill() &&
562 !II->isDebugValue()) {
563 HasAnyRealCode = true;
567 if (ShouldPrintDebugScopes) {
568 if (TimePassesIsEnabled) {
569 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
577 EmitComments(*II, OutStreamer.GetCommentOS());
579 switch (II->getOpcode()) {
580 case TargetOpcode::DBG_LABEL:
581 case TargetOpcode::EH_LABEL:
582 case TargetOpcode::GC_LABEL:
583 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol());
585 case TargetOpcode::INLINEASM:
588 case TargetOpcode::DBG_VALUE:
590 if (!EmitDebugValueComment(II, *this))
594 case TargetOpcode::IMPLICIT_DEF:
595 if (isVerbose()) EmitImplicitDef(II, *this);
597 case TargetOpcode::KILL:
598 if (isVerbose()) EmitKill(II, *this);
605 if (ShouldPrintDebugScopes) {
606 if (TimePassesIsEnabled) {
607 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
616 // If the function is empty and the object file uses .subsections_via_symbols,
617 // then we need to emit *something* to the function body to prevent the
618 // labels from collapsing together. Just emit a noop.
619 if (MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) {
621 TM.getInstrInfo()->getNoopForMachoTarget(Noop);
622 if (Noop.getOpcode()) {
623 OutStreamer.AddComment("avoids zero-length function");
624 OutStreamer.EmitInstruction(Noop);
625 } else // Target not mc-ized yet.
626 OutStreamer.EmitRawText(StringRef("\tnop\n"));
629 // Emit target-specific gunk after the function body.
630 EmitFunctionBodyEnd();
632 // If the target wants a .size directive for the size of the function, emit
634 if (MAI->hasDotTypeDotSizeDirective()) {
635 // Create a symbol for the end of function, so we can get the size as
636 // difference between the function label and the temp label.
637 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
638 OutStreamer.EmitLabel(FnEndLabel);
640 const MCExpr *SizeExp =
641 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
642 MCSymbolRefExpr::Create(CurrentFnSym, OutContext),
644 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
647 // Emit post-function debug information.
649 if (TimePassesIsEnabled) {
650 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
657 if (TimePassesIsEnabled) {
658 NamedRegionTimer T(EHTimerName, DWARFGroupName);
666 // Print out jump tables referenced by the function.
669 OutStreamer.AddBlankLine();
672 /// getDebugValueLocation - Get location information encoded by DBG_VALUE
674 MachineLocation AsmPrinter::getDebugValueLocation(const MachineInstr *MI) const {
675 // Target specific DBG_VALUE instructions are handled by each target.
676 return MachineLocation();
679 bool AsmPrinter::doFinalization(Module &M) {
680 // Emit global variables.
681 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
683 EmitGlobalVariable(I);
685 // Finalize debug and EH information.
687 if (TimePassesIsEnabled) {
688 NamedRegionTimer T(EHTimerName, DWARFGroupName);
696 if (TimePassesIsEnabled) {
697 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
705 // If the target wants to know about weak references, print them all.
706 if (MAI->getWeakRefDirective()) {
707 // FIXME: This is not lazy, it would be nice to only print weak references
708 // to stuff that is actually used. Note that doing so would require targets
709 // to notice uses in operands (due to constant exprs etc). This should
710 // happen with the MC stuff eventually.
712 // Print out module-level global variables here.
713 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
715 if (!I->hasExternalWeakLinkage()) continue;
716 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
719 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
720 if (!I->hasExternalWeakLinkage()) continue;
721 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
725 if (MAI->hasSetDirective()) {
726 OutStreamer.AddBlankLine();
727 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
729 MCSymbol *Name = Mang->getSymbol(I);
731 const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
732 MCSymbol *Target = Mang->getSymbol(GV);
734 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
735 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
736 else if (I->hasWeakLinkage())
737 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
739 assert(I->hasLocalLinkage() && "Invalid alias linkage");
741 EmitVisibility(Name, I->getVisibility());
743 // Emit the directives as assignments aka .set:
744 OutStreamer.EmitAssignment(Name,
745 MCSymbolRefExpr::Create(Target, OutContext));
749 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
750 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
751 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
752 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
753 MP->finishAssembly(*this);
755 // If we don't have any trampolines, then we don't require stack memory
756 // to be executable. Some targets have a directive to declare this.
757 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
758 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
759 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext))
760 OutStreamer.SwitchSection(S);
762 // Allow the target to emit any magic that it wants at the end of the file,
763 // after everything else has gone out.
766 delete Mang; Mang = 0;
769 OutStreamer.Finish();
773 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
775 // Get the function symbol.
776 CurrentFnSym = Mang->getSymbol(MF.getFunction());
779 LI = &getAnalysis<MachineLoopInfo>();
783 // SectionCPs - Keep track the alignment, constpool entries per Section.
787 SmallVector<unsigned, 4> CPEs;
788 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
792 /// EmitConstantPool - Print to the current output stream assembly
793 /// representations of the constants in the constant pool MCP. This is
794 /// used to print out constants which have been "spilled to memory" by
795 /// the code generator.
797 void AsmPrinter::EmitConstantPool() {
798 const MachineConstantPool *MCP = MF->getConstantPool();
799 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
800 if (CP.empty()) return;
802 // Calculate sections for constant pool entries. We collect entries to go into
803 // the same section together to reduce amount of section switch statements.
804 SmallVector<SectionCPs, 4> CPSections;
805 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
806 const MachineConstantPoolEntry &CPE = CP[i];
807 unsigned Align = CPE.getAlignment();
810 switch (CPE.getRelocationInfo()) {
811 default: llvm_unreachable("Unknown section kind");
812 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
814 Kind = SectionKind::getReadOnlyWithRelLocal();
817 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
818 case 4: Kind = SectionKind::getMergeableConst4(); break;
819 case 8: Kind = SectionKind::getMergeableConst8(); break;
820 case 16: Kind = SectionKind::getMergeableConst16();break;
821 default: Kind = SectionKind::getMergeableConst(); break;
825 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
827 // The number of sections are small, just do a linear search from the
828 // last section to the first.
830 unsigned SecIdx = CPSections.size();
831 while (SecIdx != 0) {
832 if (CPSections[--SecIdx].S == S) {
838 SecIdx = CPSections.size();
839 CPSections.push_back(SectionCPs(S, Align));
842 if (Align > CPSections[SecIdx].Alignment)
843 CPSections[SecIdx].Alignment = Align;
844 CPSections[SecIdx].CPEs.push_back(i);
847 // Now print stuff into the calculated sections.
848 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
849 OutStreamer.SwitchSection(CPSections[i].S);
850 EmitAlignment(Log2_32(CPSections[i].Alignment));
853 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
854 unsigned CPI = CPSections[i].CPEs[j];
855 MachineConstantPoolEntry CPE = CP[CPI];
857 // Emit inter-object padding for alignment.
858 unsigned AlignMask = CPE.getAlignment() - 1;
859 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
860 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/);
862 const Type *Ty = CPE.getType();
863 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
865 // Emit the label with a comment on it.
867 OutStreamer.GetCommentOS() << "constant pool ";
868 WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(),
869 MF->getFunction()->getParent());
870 OutStreamer.GetCommentOS() << '\n';
872 OutStreamer.EmitLabel(GetCPISymbol(CPI));
874 if (CPE.isMachineConstantPoolEntry())
875 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
877 EmitGlobalConstant(CPE.Val.ConstVal);
882 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
883 /// by the current function to the current output stream.
885 void AsmPrinter::EmitJumpTableInfo() {
886 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
887 if (MJTI == 0) return;
888 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
889 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
890 if (JT.empty()) return;
892 // Pick the directive to use to print the jump table entries, and switch to
893 // the appropriate section.
894 const Function *F = MF->getFunction();
895 bool JTInDiffSection = false;
896 if (// In PIC mode, we need to emit the jump table to the same section as the
897 // function body itself, otherwise the label differences won't make sense.
898 // FIXME: Need a better predicate for this: what about custom entries?
899 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
900 // We should also do if the section name is NULL or function is declared
901 // in discardable section
902 // FIXME: this isn't the right predicate, should be based on the MCSection
904 F->isWeakForLinker()) {
905 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
907 // Otherwise, drop it in the readonly section.
908 const MCSection *ReadOnlySection =
909 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
910 OutStreamer.SwitchSection(ReadOnlySection);
911 JTInDiffSection = true;
914 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData())));
916 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
917 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
919 // If this jump table was deleted, ignore it.
920 if (JTBBs.empty()) continue;
922 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
923 // .set directive for each unique entry. This reduces the number of
924 // relocations the assembler will generate for the jump table.
925 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
926 MAI->hasSetDirective()) {
927 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
928 const TargetLowering *TLI = TM.getTargetLowering();
929 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
930 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
931 const MachineBasicBlock *MBB = JTBBs[ii];
932 if (!EmittedSets.insert(MBB)) continue;
934 // .set LJTSet, LBB32-base
936 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
937 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
938 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
942 // On some targets (e.g. Darwin) we want to emit two consequtive labels
943 // before each jump table. The first label is never referenced, but tells
944 // the assembler and linker the extents of the jump table object. The
945 // second label is actually referenced by the code.
946 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
947 // FIXME: This doesn't have to have any specific name, just any randomly
948 // named and numbered 'l' label would work. Simplify GetJTISymbol.
949 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
951 OutStreamer.EmitLabel(GetJTISymbol(JTI));
953 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
954 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
958 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
960 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
961 const MachineBasicBlock *MBB,
962 unsigned UID) const {
963 const MCExpr *Value = 0;
964 switch (MJTI->getEntryKind()) {
965 case MachineJumpTableInfo::EK_Inline:
966 llvm_unreachable("Cannot emit EK_Inline jump table entry"); break;
967 case MachineJumpTableInfo::EK_Custom32:
968 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
971 case MachineJumpTableInfo::EK_BlockAddress:
972 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
974 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
976 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
977 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
978 // with a relocation as gp-relative, e.g.:
980 MCSymbol *MBBSym = MBB->getSymbol();
981 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
985 case MachineJumpTableInfo::EK_LabelDifference32: {
986 // EK_LabelDifference32 - Each entry is the address of the block minus
987 // the address of the jump table. This is used for PIC jump tables where
988 // gprel32 is not supported. e.g.:
989 // .word LBB123 - LJTI1_2
990 // If the .set directive is supported, this is emitted as:
991 // .set L4_5_set_123, LBB123 - LJTI1_2
992 // .word L4_5_set_123
994 // If we have emitted set directives for the jump table entries, print
995 // them rather than the entries themselves. If we're emitting PIC, then
996 // emit the table entries as differences between two text section labels.
997 if (MAI->hasSetDirective()) {
998 // If we used .set, reference the .set's symbol.
999 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
1003 // Otherwise, use the difference as the jump table entry.
1004 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1005 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
1006 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
1011 assert(Value && "Unknown entry kind!");
1013 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData());
1014 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0);
1018 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
1019 /// special global used by LLVM. If so, emit it and return true, otherwise
1020 /// do nothing and return false.
1021 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
1022 if (GV->getName() == "llvm.used") {
1023 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
1024 EmitLLVMUsedList(GV->getInitializer());
1028 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
1029 if (GV->getSection() == "llvm.metadata" ||
1030 GV->hasAvailableExternallyLinkage())
1033 if (!GV->hasAppendingLinkage()) return false;
1035 assert(GV->hasInitializer() && "Not a special LLVM global!");
1037 const TargetData *TD = TM.getTargetData();
1038 unsigned Align = Log2_32(TD->getPointerPrefAlignment());
1039 if (GV->getName() == "llvm.global_ctors") {
1040 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection());
1041 EmitAlignment(Align);
1042 EmitXXStructorList(GV->getInitializer());
1044 if (TM.getRelocationModel() == Reloc::Static &&
1045 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1046 StringRef Sym(".constructors_used");
1047 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1053 if (GV->getName() == "llvm.global_dtors") {
1054 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection());
1055 EmitAlignment(Align);
1056 EmitXXStructorList(GV->getInitializer());
1058 if (TM.getRelocationModel() == Reloc::Static &&
1059 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1060 StringRef Sym(".destructors_used");
1061 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1070 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1071 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1072 /// is true, as being used with this directive.
1073 void AsmPrinter::EmitLLVMUsedList(Constant *List) {
1074 // Should be an array of 'i8*'.
1075 ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1076 if (InitList == 0) return;
1078 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1079 const GlobalValue *GV =
1080 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1081 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
1082 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip);
1086 /// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the
1087 /// function pointers, ignoring the init priority.
1088 void AsmPrinter::EmitXXStructorList(Constant *List) {
1089 // Should be an array of '{ int, void ()* }' structs. The first value is the
1090 // init priority, which we ignore.
1091 if (!isa<ConstantArray>(List)) return;
1092 ConstantArray *InitList = cast<ConstantArray>(List);
1093 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
1094 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
1095 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs.
1097 if (CS->getOperand(1)->isNullValue())
1098 return; // Found a null terminator, exit printing.
1099 // Emit the function pointer.
1100 EmitGlobalConstant(CS->getOperand(1));
1104 //===--------------------------------------------------------------------===//
1105 // Emission and print routines
1108 /// EmitInt8 - Emit a byte directive and value.
1110 void AsmPrinter::EmitInt8(int Value) const {
1111 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/);
1114 /// EmitInt16 - Emit a short directive and value.
1116 void AsmPrinter::EmitInt16(int Value) const {
1117 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/);
1120 /// EmitInt32 - Emit a long directive and value.
1122 void AsmPrinter::EmitInt32(int Value) const {
1123 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/);
1126 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
1127 /// in bytes of the directive is specified by Size and Hi/Lo specify the
1128 /// labels. This implicitly uses .set if it is available.
1129 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1130 unsigned Size) const {
1131 // Get the Hi-Lo expression.
1132 const MCExpr *Diff =
1133 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1134 MCSymbolRefExpr::Create(Lo, OutContext),
1137 if (!MAI->hasSetDirective()) {
1138 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/);
1142 // Otherwise, emit with .set (aka assignment).
1143 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1144 OutStreamer.EmitAssignment(SetLabel, Diff);
1145 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/);
1148 /// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo"
1149 /// where the size in bytes of the directive is specified by Size and Hi/Lo
1150 /// specify the labels. This implicitly uses .set if it is available.
1151 void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset,
1152 const MCSymbol *Lo, unsigned Size)
1155 // Emit Hi+Offset - Lo
1156 // Get the Hi+Offset expression.
1157 const MCExpr *Plus =
1158 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext),
1159 MCConstantExpr::Create(Offset, OutContext),
1162 // Get the Hi+Offset-Lo expression.
1163 const MCExpr *Diff =
1164 MCBinaryExpr::CreateSub(Plus,
1165 MCSymbolRefExpr::Create(Lo, OutContext),
1168 if (!MAI->hasSetDirective())
1169 OutStreamer.EmitValue(Diff, 4, 0/*AddrSpace*/);
1171 // Otherwise, emit with .set (aka assignment).
1172 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1173 OutStreamer.EmitAssignment(SetLabel, Diff);
1174 OutStreamer.EmitSymbolValue(SetLabel, 4, 0/*AddrSpace*/);
1179 //===----------------------------------------------------------------------===//
1181 // EmitAlignment - Emit an alignment directive to the specified power of
1182 // two boundary. For example, if you pass in 3 here, you will get an 8
1183 // byte alignment. If a global value is specified, and if that global has
1184 // an explicit alignment requested, it will override the alignment request
1185 // if required for correctness.
1187 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV) const {
1188 if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getTargetData(), NumBits);
1190 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.
1192 if (getCurrentSection()->getKind().isText())
1193 OutStreamer.EmitCodeAlignment(1 << NumBits);
1195 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
1198 //===----------------------------------------------------------------------===//
1199 // Constant emission.
1200 //===----------------------------------------------------------------------===//
1202 /// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
1204 static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) {
1205 MCContext &Ctx = AP.OutContext;
1207 if (CV->isNullValue() || isa<UndefValue>(CV))
1208 return MCConstantExpr::Create(0, Ctx);
1210 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1211 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1213 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1214 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx);
1215 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1216 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1218 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1220 llvm_unreachable("Unknown constant value to lower!");
1221 return MCConstantExpr::Create(0, Ctx);
1224 switch (CE->getOpcode()) {
1226 // If the code isn't optimized, there may be outstanding folding
1227 // opportunities. Attempt to fold the expression using TargetData as a
1228 // last resort before giving up.
1230 ConstantFoldConstantExpression(CE, AP.TM.getTargetData()))
1232 return LowerConstant(C, AP);
1236 llvm_unreachable("FIXME: Don't support this constant expr");
1237 case Instruction::GetElementPtr: {
1238 const TargetData &TD = *AP.TM.getTargetData();
1239 // Generate a symbolic expression for the byte address
1240 const Constant *PtrVal = CE->getOperand(0);
1241 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
1242 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0],
1245 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
1249 // Truncate/sext the offset to the pointer size.
1250 if (TD.getPointerSizeInBits() != 64) {
1251 int SExtAmount = 64-TD.getPointerSizeInBits();
1252 Offset = (Offset << SExtAmount) >> SExtAmount;
1255 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1259 case Instruction::Trunc:
1260 // We emit the value and depend on the assembler to truncate the generated
1261 // expression properly. This is important for differences between
1262 // blockaddress labels. Since the two labels are in the same function, it
1263 // is reasonable to treat their delta as a 32-bit value.
1265 case Instruction::BitCast:
1266 return LowerConstant(CE->getOperand(0), AP);
1268 case Instruction::IntToPtr: {
1269 const TargetData &TD = *AP.TM.getTargetData();
1270 // Handle casts to pointers by changing them into casts to the appropriate
1271 // integer type. This promotes constant folding and simplifies this code.
1272 Constant *Op = CE->getOperand(0);
1273 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
1275 return LowerConstant(Op, AP);
1278 case Instruction::PtrToInt: {
1279 const TargetData &TD = *AP.TM.getTargetData();
1280 // Support only foldable casts to/from pointers that can be eliminated by
1281 // changing the pointer to the appropriately sized integer type.
1282 Constant *Op = CE->getOperand(0);
1283 const Type *Ty = CE->getType();
1285 const MCExpr *OpExpr = LowerConstant(Op, AP);
1287 // We can emit the pointer value into this slot if the slot is an
1288 // integer slot equal to the size of the pointer.
1289 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
1292 // Otherwise the pointer is smaller than the resultant integer, mask off
1293 // the high bits so we are sure to get a proper truncation if the input is
1295 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
1296 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1297 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1300 // The MC library also has a right-shift operator, but it isn't consistently
1301 // signed or unsigned between different targets.
1302 case Instruction::Add:
1303 case Instruction::Sub:
1304 case Instruction::Mul:
1305 case Instruction::SDiv:
1306 case Instruction::SRem:
1307 case Instruction::Shl:
1308 case Instruction::And:
1309 case Instruction::Or:
1310 case Instruction::Xor: {
1311 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP);
1312 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP);
1313 switch (CE->getOpcode()) {
1314 default: llvm_unreachable("Unknown binary operator constant cast expr");
1315 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1316 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1317 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1318 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1319 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1320 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1321 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1322 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1323 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1329 static void EmitGlobalConstantImpl(const Constant *C, unsigned AddrSpace,
1332 static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
1334 if (AddrSpace != 0 || !CA->isString()) {
1335 // Not a string. Print the values in successive locations
1336 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1337 EmitGlobalConstantImpl(CA->getOperand(i), AddrSpace, AP);
1341 // Otherwise, it can be emitted as .ascii.
1342 SmallVector<char, 128> TmpVec;
1343 TmpVec.reserve(CA->getNumOperands());
1344 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1345 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
1347 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace);
1350 static void EmitGlobalConstantVector(const ConstantVector *CV,
1351 unsigned AddrSpace, AsmPrinter &AP) {
1352 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1353 EmitGlobalConstantImpl(CV->getOperand(i), AddrSpace, AP);
1356 static void EmitGlobalConstantStruct(const ConstantStruct *CS,
1357 unsigned AddrSpace, AsmPrinter &AP) {
1358 // Print the fields in successive locations. Pad to align if needed!
1359 const TargetData *TD = AP.TM.getTargetData();
1360 unsigned Size = TD->getTypeAllocSize(CS->getType());
1361 const StructLayout *Layout = TD->getStructLayout(CS->getType());
1362 uint64_t SizeSoFar = 0;
1363 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1364 const Constant *Field = CS->getOperand(i);
1366 // Check if padding is needed and insert one or more 0s.
1367 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
1368 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1369 - Layout->getElementOffset(i)) - FieldSize;
1370 SizeSoFar += FieldSize + PadSize;
1372 // Now print the actual field value.
1373 EmitGlobalConstantImpl(Field, AddrSpace, AP);
1375 // Insert padding - this may include padding to increase the size of the
1376 // current field up to the ABI size (if the struct is not packed) as well
1377 // as padding to ensure that the next field starts at the right offset.
1378 AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
1380 assert(SizeSoFar == Layout->getSizeInBytes() &&
1381 "Layout of constant struct may be incorrect!");
1384 static void EmitGlobalConstantUnion(const ConstantUnion *CU,
1385 unsigned AddrSpace, AsmPrinter &AP) {
1386 const TargetData *TD = AP.TM.getTargetData();
1387 unsigned Size = TD->getTypeAllocSize(CU->getType());
1389 const Constant *Contents = CU->getOperand(0);
1390 unsigned FilledSize = TD->getTypeAllocSize(Contents->getType());
1392 // Print the actually filled part
1393 EmitGlobalConstantImpl(Contents, AddrSpace, AP);
1395 // And pad with enough zeroes
1396 AP.OutStreamer.EmitZeros(Size-FilledSize, AddrSpace);
1399 static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
1401 // FP Constants are printed as integer constants to avoid losing
1403 if (CFP->getType()->isDoubleTy()) {
1404 if (AP.isVerbose()) {
1405 double Val = CFP->getValueAPF().convertToDouble();
1406 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n';
1409 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1410 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1414 if (CFP->getType()->isFloatTy()) {
1415 if (AP.isVerbose()) {
1416 float Val = CFP->getValueAPF().convertToFloat();
1417 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n';
1419 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1420 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace);
1424 if (CFP->getType()->isX86_FP80Ty()) {
1425 // all long double variants are printed as hex
1426 // API needed to prevent premature destruction
1427 APInt API = CFP->getValueAPF().bitcastToAPInt();
1428 const uint64_t *p = API.getRawData();
1429 if (AP.isVerbose()) {
1430 // Convert to double so we can print the approximate val as a comment.
1431 APFloat DoubleVal = CFP->getValueAPF();
1433 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1435 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= "
1436 << DoubleVal.convertToDouble() << '\n';
1439 if (AP.TM.getTargetData()->isBigEndian()) {
1440 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1441 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1443 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1444 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1447 // Emit the tail padding for the long double.
1448 const TargetData &TD = *AP.TM.getTargetData();
1449 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
1450 TD.getTypeStoreSize(CFP->getType()), AddrSpace);
1454 assert(CFP->getType()->isPPC_FP128Ty() &&
1455 "Floating point constant type not handled");
1456 // All long double variants are printed as hex
1457 // API needed to prevent premature destruction.
1458 APInt API = CFP->getValueAPF().bitcastToAPInt();
1459 const uint64_t *p = API.getRawData();
1460 if (AP.TM.getTargetData()->isBigEndian()) {
1461 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1462 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1464 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1465 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1469 static void EmitGlobalConstantLargeInt(const ConstantInt *CI,
1470 unsigned AddrSpace, AsmPrinter &AP) {
1471 const TargetData *TD = AP.TM.getTargetData();
1472 unsigned BitWidth = CI->getBitWidth();
1473 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
1475 // We don't expect assemblers to support integer data directives
1476 // for more than 64 bits, so we emit the data in at most 64-bit
1477 // quantities at a time.
1478 const uint64_t *RawData = CI->getValue().getRawData();
1479 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1480 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1481 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1485 static void EmitGlobalConstantImpl(const Constant *CV, unsigned AddrSpace,
1487 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) {
1488 uint64_t Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType());
1489 return AP.OutStreamer.EmitZeros(Size, AddrSpace);
1492 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1493 unsigned Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType());
1500 AP.OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue());
1501 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1504 EmitGlobalConstantLargeInt(CI, AddrSpace, AP);
1509 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1510 return EmitGlobalConstantArray(CVA, AddrSpace, AP);
1512 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1513 return EmitGlobalConstantStruct(CVS, AddrSpace, AP);
1515 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1516 return EmitGlobalConstantFP(CFP, AddrSpace, AP);
1518 if (isa<ConstantPointerNull>(CV)) {
1519 unsigned Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType());
1520 AP.OutStreamer.EmitIntValue(0, Size, AddrSpace);
1524 if (const ConstantUnion *CVU = dyn_cast<ConstantUnion>(CV))
1525 return EmitGlobalConstantUnion(CVU, AddrSpace, AP);
1527 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1528 return EmitGlobalConstantVector(V, AddrSpace, AP);
1530 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1531 // thread the streamer with EmitValue.
1532 AP.OutStreamer.EmitValue(LowerConstant(CV, AP),
1533 AP.TM.getTargetData()->getTypeAllocSize(CV->getType()),
1537 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1538 void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1539 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1541 EmitGlobalConstantImpl(CV, AddrSpace, *this);
1542 else if (MAI->hasSubsectionsViaSymbols()) {
1543 // If the global has zero size, emit a single byte so that two labels don't
1544 // look like they are at the same location.
1545 OutStreamer.EmitIntValue(0, 1, AddrSpace);
1549 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1550 // Target doesn't support this yet!
1551 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1554 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1556 OS << '+' << Offset;
1557 else if (Offset < 0)
1561 //===----------------------------------------------------------------------===//
1562 // Symbol Lowering Routines.
1563 //===----------------------------------------------------------------------===//
1565 /// GetTempSymbol - Return the MCSymbol corresponding to the assembler
1566 /// temporary label with the specified stem and unique ID.
1567 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const {
1568 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) +
1572 /// GetTempSymbol - Return an assembler temporary label with the specified
1574 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const {
1575 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix())+
1580 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
1581 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
1584 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
1585 return MMI->getAddrLabelSymbol(BB);
1588 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1589 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1590 return OutContext.GetOrCreateSymbol
1591 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
1592 + "_" + Twine(CPID));
1595 /// GetJTISymbol - Return the symbol for the specified jump table entry.
1596 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1597 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
1600 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
1601 /// FIXME: privatize to AsmPrinter.
1602 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
1603 return OutContext.GetOrCreateSymbol
1604 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
1605 Twine(UID) + "_set_" + Twine(MBBID));
1608 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1609 /// global value name as its base, with the specified suffix, and where the
1610 /// symbol is forced to have private linkage if ForcePrivate is true.
1611 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1613 bool ForcePrivate) const {
1614 SmallString<60> NameStr;
1615 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1616 NameStr.append(Suffix.begin(), Suffix.end());
1617 return OutContext.GetOrCreateSymbol(NameStr.str());
1620 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
1622 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
1623 SmallString<60> NameStr;
1624 Mang->getNameWithPrefix(NameStr, Sym);
1625 return OutContext.GetOrCreateSymbol(NameStr.str());
1630 /// PrintParentLoopComment - Print comments about parent loops of this one.
1631 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1632 unsigned FunctionNumber) {
1633 if (Loop == 0) return;
1634 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
1635 OS.indent(Loop->getLoopDepth()*2)
1636 << "Parent Loop BB" << FunctionNumber << "_"
1637 << Loop->getHeader()->getNumber()
1638 << " Depth=" << Loop->getLoopDepth() << '\n';
1642 /// PrintChildLoopComment - Print comments about child loops within
1643 /// the loop for this basic block, with nesting.
1644 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1645 unsigned FunctionNumber) {
1646 // Add child loop information
1647 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
1648 OS.indent((*CL)->getLoopDepth()*2)
1649 << "Child Loop BB" << FunctionNumber << "_"
1650 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
1652 PrintChildLoopComment(OS, *CL, FunctionNumber);
1656 /// EmitBasicBlockLoopComments - Pretty-print comments for basic blocks.
1657 static void EmitBasicBlockLoopComments(const MachineBasicBlock &MBB,
1658 const MachineLoopInfo *LI,
1659 const AsmPrinter &AP) {
1660 // Add loop depth information
1661 const MachineLoop *Loop = LI->getLoopFor(&MBB);
1662 if (Loop == 0) return;
1664 MachineBasicBlock *Header = Loop->getHeader();
1665 assert(Header && "No header for loop");
1667 // If this block is not a loop header, just print out what is the loop header
1669 if (Header != &MBB) {
1670 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
1671 Twine(AP.getFunctionNumber())+"_" +
1672 Twine(Loop->getHeader()->getNumber())+
1673 " Depth="+Twine(Loop->getLoopDepth()));
1677 // Otherwise, it is a loop header. Print out information about child and
1679 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
1681 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
1684 OS.indent(Loop->getLoopDepth()*2-2);
1689 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
1691 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
1695 /// EmitBasicBlockStart - This method prints the label for the specified
1696 /// MachineBasicBlock, an alignment (if present) and a comment describing
1697 /// it if appropriate.
1698 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
1699 // Emit an alignment directive for this block, if needed.
1700 if (unsigned Align = MBB->getAlignment())
1701 EmitAlignment(Log2_32(Align));
1703 // If the block has its address taken, emit any labels that were used to
1704 // reference the block. It is possible that there is more than one label
1705 // here, because multiple LLVM BB's may have been RAUW'd to this block after
1706 // the references were generated.
1707 if (MBB->hasAddressTaken()) {
1708 const BasicBlock *BB = MBB->getBasicBlock();
1710 OutStreamer.AddComment("Block address taken");
1712 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
1714 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
1715 OutStreamer.EmitLabel(Syms[i]);
1718 // Print the main label for the block.
1719 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
1720 if (isVerbose() && OutStreamer.hasRawTextSupport()) {
1721 if (const BasicBlock *BB = MBB->getBasicBlock())
1723 OutStreamer.AddComment("%" + BB->getName());
1725 EmitBasicBlockLoopComments(*MBB, LI, *this);
1727 // NOTE: Want this comment at start of line, don't emit with AddComment.
1728 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" +
1729 Twine(MBB->getNumber()) + ":");
1733 if (const BasicBlock *BB = MBB->getBasicBlock())
1735 OutStreamer.AddComment("%" + BB->getName());
1736 EmitBasicBlockLoopComments(*MBB, LI, *this);
1739 OutStreamer.EmitLabel(MBB->getSymbol());
1743 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility) const {
1744 MCSymbolAttr Attr = MCSA_Invalid;
1746 switch (Visibility) {
1748 case GlobalValue::HiddenVisibility:
1749 Attr = MAI->getHiddenVisibilityAttr();
1751 case GlobalValue::ProtectedVisibility:
1752 Attr = MAI->getProtectedVisibilityAttr();
1756 if (Attr != MCSA_Invalid)
1757 OutStreamer.EmitSymbolAttribute(Sym, Attr);
1760 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
1761 /// exactly one predecessor and the control transfer mechanism between
1762 /// the predecessor and this block is a fall-through.
1764 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
1765 // If this is a landing pad, it isn't a fall through. If it has no preds,
1766 // then nothing falls through to it.
1767 if (MBB->isLandingPad() || MBB->pred_empty())
1770 // If there isn't exactly one predecessor, it can't be a fall through.
1771 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
1773 if (PI2 != MBB->pred_end())
1776 // The predecessor has to be immediately before this block.
1777 const MachineBasicBlock *Pred = *PI;
1779 if (!Pred->isLayoutSuccessor(MBB))
1782 // If the block is completely empty, then it definitely does fall through.
1786 // Otherwise, check the last instruction.
1787 const MachineInstr &LastInst = Pred->back();
1788 return !LastInst.getDesc().isBarrier();
1793 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1794 if (!S->usesMetadata())
1797 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
1798 gcp_map_type::iterator GCPI = GCMap.find(S);
1799 if (GCPI != GCMap.end())
1800 return GCPI->second;
1802 const char *Name = S->getName().c_str();
1804 for (GCMetadataPrinterRegistry::iterator
1805 I = GCMetadataPrinterRegistry::begin(),
1806 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1807 if (strcmp(Name, I->getName()) == 0) {
1808 GCMetadataPrinter *GMP = I->instantiate();
1810 GCMap.insert(std::make_pair(S, GMP));
1814 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));