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 AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
65 : MachineFunctionPass(&ID),
66 TM(tm), MAI(tm.getMCAsmInfo()),
67 OutContext(Streamer.getContext()),
68 OutStreamer(Streamer),
69 LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {
70 DD = 0; DE = 0; MMI = 0; LI = 0;
71 GCMetadataPrinters = 0;
72 VerboseAsm = Streamer.isVerboseAsm();
75 AsmPrinter::~AsmPrinter() {
76 assert(DD == 0 && DE == 0 && "Debug/EH info didn't get finalized");
78 if (GCMetadataPrinters != 0) {
79 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
81 for (gcp_map_type::iterator I = GCMap.begin(), E = GCMap.end(); I != E; ++I)
84 GCMetadataPrinters = 0;
90 /// getFunctionNumber - Return a unique ID for the current function.
92 unsigned AsmPrinter::getFunctionNumber() const {
93 return MF->getFunctionNumber();
96 const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
97 return TM.getTargetLowering()->getObjFileLowering();
101 /// getTargetData - Return information about data layout.
102 const TargetData &AsmPrinter::getTargetData() const {
103 return *TM.getTargetData();
106 /// getCurrentSection() - Return the current section we are emitting to.
107 const MCSection *AsmPrinter::getCurrentSection() const {
108 return OutStreamer.getCurrentSection();
113 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
114 AU.setPreservesAll();
115 MachineFunctionPass::getAnalysisUsage(AU);
116 AU.addRequired<MachineModuleInfo>();
117 AU.addRequired<GCModuleInfo>();
119 AU.addRequired<MachineLoopInfo>();
122 bool AsmPrinter::doInitialization(Module &M) {
123 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
124 MMI->AnalyzeModule(M);
126 // Initialize TargetLoweringObjectFile.
127 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
128 .Initialize(OutContext, TM);
130 Mang = new Mangler(OutContext, *TM.getTargetData());
132 // Allow the target to emit any magic that it wants at the start of the file.
133 EmitStartOfAsmFile(M);
135 // Very minimal debug info. It is ignored if we emit actual debug info. If we
136 // don't, this at least helps the user find where a global came from.
137 if (MAI->hasSingleParameterDotFile()) {
139 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
142 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
143 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
144 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
145 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
146 MP->beginAssembly(*this);
148 // Emit module-level inline asm if it exists.
149 if (!M.getModuleInlineAsm().empty()) {
150 OutStreamer.AddComment("Start of file scope inline assembly");
151 OutStreamer.AddBlankLine();
152 EmitInlineAsm(M.getModuleInlineAsm(), 0/*no loc cookie*/);
153 OutStreamer.AddComment("End of file scope inline assembly");
154 OutStreamer.AddBlankLine();
157 if (MAI->doesSupportDebugInformation())
158 DD = new DwarfDebug(this, &M);
160 if (MAI->doesSupportExceptionHandling())
161 DE = new DwarfException(this);
166 void AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const {
167 switch ((GlobalValue::LinkageTypes)Linkage) {
168 case GlobalValue::CommonLinkage:
169 case GlobalValue::LinkOnceAnyLinkage:
170 case GlobalValue::LinkOnceODRLinkage:
171 case GlobalValue::WeakAnyLinkage:
172 case GlobalValue::WeakODRLinkage:
173 case GlobalValue::LinkerPrivateLinkage:
174 if (MAI->getWeakDefDirective() != 0) {
176 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
177 // .weak_definition _foo
178 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
179 } else if (const char *LinkOnce = MAI->getLinkOnceDirective()) {
181 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
182 // FIXME: linkonce should be a section attribute, handled by COFF Section
184 // http://sourceware.org/binutils/docs-2.20/as/Linkonce.html#Linkonce
186 // FIXME: It would be nice to use .linkonce samesize for non-common
188 OutStreamer.EmitRawText(StringRef(LinkOnce));
191 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
194 case GlobalValue::DLLExportLinkage:
195 case GlobalValue::AppendingLinkage:
196 // FIXME: appending linkage variables should go into a section of
197 // their name or something. For now, just emit them as external.
198 case GlobalValue::ExternalLinkage:
199 // If external or appending, declare as a global symbol.
201 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
203 case GlobalValue::PrivateLinkage:
204 case GlobalValue::InternalLinkage:
207 llvm_unreachable("Unknown linkage type!");
212 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
213 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
214 if (!GV->hasInitializer()) // External globals require no code.
217 // Check to see if this is a special global used by LLVM, if so, emit it.
218 if (EmitSpecialLLVMGlobal(GV))
221 MCSymbol *GVSym = Mang->getSymbol(GV);
222 EmitVisibility(GVSym, GV->getVisibility());
224 if (MAI->hasDotTypeDotSizeDirective())
225 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
227 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
229 const TargetData *TD = TM.getTargetData();
230 unsigned Size = TD->getTypeAllocSize(GV->getType()->getElementType());
232 // If the alignment is specified, we *must* obey it. Overaligning a global
233 // with a specified alignment is a prompt way to break globals emitted to
234 // sections and expected to be contiguous (e.g. ObjC metadata).
236 if (unsigned GVAlign = GV->getAlignment())
237 AlignLog = Log2_32(GVAlign);
239 AlignLog = TD->getPreferredAlignmentLog(GV);
241 // Handle common and BSS local symbols (.lcomm).
242 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
243 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
246 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
247 /*PrintType=*/false, GV->getParent());
248 OutStreamer.GetCommentOS() << '\n';
251 // Handle common symbols.
252 if (GVKind.isCommon()) {
254 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
258 // Handle local BSS symbols.
259 if (MAI->hasMachoZeroFillDirective()) {
260 const MCSection *TheSection =
261 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
262 // .zerofill __DATA, __bss, _foo, 400, 5
263 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
267 if (MAI->hasLCOMMDirective()) {
269 OutStreamer.EmitLocalCommonSymbol(GVSym, Size);
274 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
276 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
280 const MCSection *TheSection =
281 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
283 // Handle the zerofill directive on darwin, which is a special form of BSS
285 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
287 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
288 // .zerofill __DATA, __common, _foo, 400, 5
289 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
293 OutStreamer.SwitchSection(TheSection);
295 EmitLinkage(GV->getLinkage(), GVSym);
296 EmitAlignment(AlignLog, GV);
299 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
300 /*PrintType=*/false, GV->getParent());
301 OutStreamer.GetCommentOS() << '\n';
303 OutStreamer.EmitLabel(GVSym);
305 EmitGlobalConstant(GV->getInitializer());
307 if (MAI->hasDotTypeDotSizeDirective())
309 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
311 OutStreamer.AddBlankLine();
314 /// EmitFunctionHeader - This method emits the header for the current
316 void AsmPrinter::EmitFunctionHeader() {
317 // Print out constants referenced by the function
320 // Print the 'header' of function.
321 const Function *F = MF->getFunction();
323 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
324 EmitVisibility(CurrentFnSym, F->getVisibility());
326 EmitLinkage(F->getLinkage(), CurrentFnSym);
327 EmitAlignment(MF->getAlignment(), F);
329 if (MAI->hasDotTypeDotSizeDirective())
330 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
333 WriteAsOperand(OutStreamer.GetCommentOS(), F,
334 /*PrintType=*/false, F->getParent());
335 OutStreamer.GetCommentOS() << '\n';
338 // Emit the CurrentFnSym. This is a virtual function to allow targets to
339 // do their wild and crazy things as required.
340 EmitFunctionEntryLabel();
342 // If the function had address-taken blocks that got deleted, then we have
343 // references to the dangling symbols. Emit them at the start of the function
344 // so that we don't get references to undefined symbols.
345 std::vector<MCSymbol*> DeadBlockSyms;
346 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
347 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
348 OutStreamer.AddComment("Address taken block that was later removed");
349 OutStreamer.EmitLabel(DeadBlockSyms[i]);
352 // Add some workaround for linkonce linkage on Cygwin\MinGW.
353 if (MAI->getLinkOnceDirective() != 0 &&
354 (F->hasLinkOnceLinkage() || F->hasWeakLinkage())) {
355 // FIXME: What is this?
357 OutContext.GetOrCreateSymbol(Twine("Lllvm$workaround$fake$stub$")+
358 CurrentFnSym->getName());
359 OutStreamer.EmitLabel(FakeStub);
362 // Emit pre-function debug and/or EH information.
364 if (TimePassesIsEnabled) {
365 NamedRegionTimer T(EHTimerName, DWARFGroupName);
366 DE->BeginFunction(MF);
368 DE->BeginFunction(MF);
372 if (TimePassesIsEnabled) {
373 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
374 DD->beginFunction(MF);
376 DD->beginFunction(MF);
381 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
382 /// function. This can be overridden by targets as required to do custom stuff.
383 void AsmPrinter::EmitFunctionEntryLabel() {
384 OutStreamer.EmitLabel(CurrentFnSym);
388 /// EmitComments - Pretty-print comments for instructions.
389 static void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
390 const MachineFunction *MF = MI.getParent()->getParent();
391 const TargetMachine &TM = MF->getTarget();
393 DebugLoc DL = MI.getDebugLoc();
394 if (!DL.isUnknown()) { // Print source line info.
395 DIScope Scope(DL.getScope(MF->getFunction()->getContext()));
396 // Omit the directory, because it's likely to be long and uninteresting.
398 CommentOS << Scope.getFilename();
400 CommentOS << "<unknown>";
401 CommentOS << ':' << DL.getLine();
402 if (DL.getCol() != 0)
403 CommentOS << ':' << DL.getCol();
407 // Check for spills and reloads
410 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
412 // We assume a single instruction only has a spill or reload, not
414 const MachineMemOperand *MMO;
415 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
416 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
417 MMO = *MI.memoperands_begin();
418 CommentOS << MMO->getSize() << "-byte Reload\n";
420 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
421 if (FrameInfo->isSpillSlotObjectIndex(FI))
422 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
423 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
424 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
425 MMO = *MI.memoperands_begin();
426 CommentOS << MMO->getSize() << "-byte Spill\n";
428 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
429 if (FrameInfo->isSpillSlotObjectIndex(FI))
430 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
433 // Check for spill-induced copies
434 unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
435 if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg,
436 SrcSubIdx, DstSubIdx)) {
437 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
438 CommentOS << " Reload Reuse\n";
442 /// EmitImplicitDef - This method emits the specified machine instruction
443 /// that is an implicit def.
444 static void EmitImplicitDef(const MachineInstr *MI, AsmPrinter &AP) {
445 unsigned RegNo = MI->getOperand(0).getReg();
446 AP.OutStreamer.AddComment(Twine("implicit-def: ") +
447 AP.TM.getRegisterInfo()->getName(RegNo));
448 AP.OutStreamer.AddBlankLine();
451 static void EmitKill(const MachineInstr *MI, AsmPrinter &AP) {
452 std::string Str = "kill:";
453 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
454 const MachineOperand &Op = MI->getOperand(i);
455 assert(Op.isReg() && "KILL instruction must have only register operands");
457 Str += AP.TM.getRegisterInfo()->getName(Op.getReg());
458 Str += (Op.isDef() ? "<def>" : "<kill>");
460 AP.OutStreamer.AddComment(Str);
461 AP.OutStreamer.AddBlankLine();
464 /// EmitDebugValueComment - This method handles the target-independent form
465 /// of DBG_VALUE, returning true if it was able to do so. A false return
466 /// means the target will need to handle MI in EmitInstruction.
467 static bool EmitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
468 // This code handles only the 3-operand target-independent form.
469 if (MI->getNumOperands() != 3)
472 SmallString<128> Str;
473 raw_svector_ostream OS(Str);
474 OS << '\t' << AP.MAI->getCommentString() << "DEBUG_VALUE: ";
476 // cast away const; DIetc do not take const operands for some reason.
477 DIVariable V(const_cast<MDNode*>(MI->getOperand(2).getMetadata()));
478 OS << V.getName() << " <- ";
480 // Register or immediate value. Register 0 means undef.
481 if (MI->getOperand(0).isFPImm()) {
482 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
483 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
484 OS << (double)APF.convertToFloat();
485 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
486 OS << APF.convertToDouble();
488 // There is no good way to print long double. Convert a copy to
489 // double. Ah well, it's only a comment.
491 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
493 OS << "(long double) " << APF.convertToDouble();
495 } else if (MI->getOperand(0).isImm()) {
496 OS << MI->getOperand(0).getImm();
498 assert(MI->getOperand(0).isReg() && "Unknown operand type");
499 if (MI->getOperand(0).getReg() == 0) {
500 // Suppress offset, it is not meaningful here.
502 // NOTE: Want this comment at start of line, don't emit with AddComment.
503 AP.OutStreamer.EmitRawText(OS.str());
506 OS << AP.TM.getRegisterInfo()->getName(MI->getOperand(0).getReg());
509 OS << '+' << MI->getOperand(1).getImm();
510 // NOTE: Want this comment at start of line, don't emit with AddComment.
511 AP.OutStreamer.EmitRawText(OS.str());
515 /// EmitFunctionBody - This method emits the body and trailer for a
517 void AsmPrinter::EmitFunctionBody() {
518 // Emit target-specific gunk before the function body.
519 EmitFunctionBodyStart();
521 bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo();
523 // Print out code for the function.
524 bool HasAnyRealCode = false;
525 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
527 // Print a label for the basic block.
528 EmitBasicBlockStart(I);
529 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
531 // Print the assembly for the instruction.
533 HasAnyRealCode = true;
537 if (ShouldPrintDebugScopes) {
538 if (TimePassesIsEnabled) {
539 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
547 EmitComments(*II, OutStreamer.GetCommentOS());
549 switch (II->getOpcode()) {
550 case TargetOpcode::DBG_LABEL:
551 case TargetOpcode::EH_LABEL:
552 case TargetOpcode::GC_LABEL:
553 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol());
555 case TargetOpcode::INLINEASM:
558 case TargetOpcode::DBG_VALUE:
560 if (!EmitDebugValueComment(II, *this))
564 case TargetOpcode::IMPLICIT_DEF:
565 if (isVerbose()) EmitImplicitDef(II, *this);
567 case TargetOpcode::KILL:
568 if (isVerbose()) EmitKill(II, *this);
575 if (ShouldPrintDebugScopes) {
576 if (TimePassesIsEnabled) {
577 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
586 // If the function is empty and the object file uses .subsections_via_symbols,
587 // then we need to emit *something* to the function body to prevent the
588 // labels from collapsing together. Just emit a noop.
589 if (MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) {
591 TM.getInstrInfo()->getNoopForMachoTarget(Noop);
592 if (Noop.getOpcode()) {
593 OutStreamer.AddComment("avoids zero-length function");
594 OutStreamer.EmitInstruction(Noop);
595 } else // Target not mc-ized yet.
596 OutStreamer.EmitRawText(StringRef("\tnop\n"));
599 // Emit target-specific gunk after the function body.
600 EmitFunctionBodyEnd();
602 // If the target wants a .size directive for the size of the function, emit
604 if (MAI->hasDotTypeDotSizeDirective()) {
605 // Create a symbol for the end of function, so we can get the size as
606 // difference between the function label and the temp label.
607 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
608 OutStreamer.EmitLabel(FnEndLabel);
610 const MCExpr *SizeExp =
611 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
612 MCSymbolRefExpr::Create(CurrentFnSym, OutContext),
614 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
617 // Emit post-function debug information.
619 if (TimePassesIsEnabled) {
620 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
627 if (TimePassesIsEnabled) {
628 NamedRegionTimer T(EHTimerName, DWARFGroupName);
636 // Print out jump tables referenced by the function.
639 OutStreamer.AddBlankLine();
643 bool AsmPrinter::doFinalization(Module &M) {
644 // Emit global variables.
645 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
647 EmitGlobalVariable(I);
649 // Finalize debug and EH information.
651 if (TimePassesIsEnabled) {
652 NamedRegionTimer T(EHTimerName, DWARFGroupName);
660 if (TimePassesIsEnabled) {
661 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
669 // If the target wants to know about weak references, print them all.
670 if (MAI->getWeakRefDirective()) {
671 // FIXME: This is not lazy, it would be nice to only print weak references
672 // to stuff that is actually used. Note that doing so would require targets
673 // to notice uses in operands (due to constant exprs etc). This should
674 // happen with the MC stuff eventually.
676 // Print out module-level global variables here.
677 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
679 if (!I->hasExternalWeakLinkage()) continue;
680 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
683 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
684 if (!I->hasExternalWeakLinkage()) continue;
685 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
689 if (MAI->hasSetDirective()) {
690 OutStreamer.AddBlankLine();
691 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
693 MCSymbol *Name = Mang->getSymbol(I);
695 const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
696 MCSymbol *Target = Mang->getSymbol(GV);
698 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
699 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
700 else if (I->hasWeakLinkage())
701 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
703 assert(I->hasLocalLinkage() && "Invalid alias linkage");
705 EmitVisibility(Name, I->getVisibility());
707 // Emit the directives as assignments aka .set:
708 OutStreamer.EmitAssignment(Name,
709 MCSymbolRefExpr::Create(Target, OutContext));
713 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
714 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
715 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
716 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
717 MP->finishAssembly(*this);
719 // If we don't have any trampolines, then we don't require stack memory
720 // to be executable. Some targets have a directive to declare this.
721 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
722 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
723 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext))
724 OutStreamer.SwitchSection(S);
726 // Allow the target to emit any magic that it wants at the end of the file,
727 // after everything else has gone out.
730 delete Mang; Mang = 0;
733 OutStreamer.Finish();
737 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
739 // Get the function symbol.
740 CurrentFnSym = Mang->getSymbol(MF.getFunction());
743 LI = &getAnalysis<MachineLoopInfo>();
747 // SectionCPs - Keep track the alignment, constpool entries per Section.
751 SmallVector<unsigned, 4> CPEs;
752 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
756 /// EmitConstantPool - Print to the current output stream assembly
757 /// representations of the constants in the constant pool MCP. This is
758 /// used to print out constants which have been "spilled to memory" by
759 /// the code generator.
761 void AsmPrinter::EmitConstantPool() {
762 const MachineConstantPool *MCP = MF->getConstantPool();
763 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
764 if (CP.empty()) return;
766 // Calculate sections for constant pool entries. We collect entries to go into
767 // the same section together to reduce amount of section switch statements.
768 SmallVector<SectionCPs, 4> CPSections;
769 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
770 const MachineConstantPoolEntry &CPE = CP[i];
771 unsigned Align = CPE.getAlignment();
774 switch (CPE.getRelocationInfo()) {
775 default: llvm_unreachable("Unknown section kind");
776 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
778 Kind = SectionKind::getReadOnlyWithRelLocal();
781 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
782 case 4: Kind = SectionKind::getMergeableConst4(); break;
783 case 8: Kind = SectionKind::getMergeableConst8(); break;
784 case 16: Kind = SectionKind::getMergeableConst16();break;
785 default: Kind = SectionKind::getMergeableConst(); break;
789 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
791 // The number of sections are small, just do a linear search from the
792 // last section to the first.
794 unsigned SecIdx = CPSections.size();
795 while (SecIdx != 0) {
796 if (CPSections[--SecIdx].S == S) {
802 SecIdx = CPSections.size();
803 CPSections.push_back(SectionCPs(S, Align));
806 if (Align > CPSections[SecIdx].Alignment)
807 CPSections[SecIdx].Alignment = Align;
808 CPSections[SecIdx].CPEs.push_back(i);
811 // Now print stuff into the calculated sections.
812 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
813 OutStreamer.SwitchSection(CPSections[i].S);
814 EmitAlignment(Log2_32(CPSections[i].Alignment));
817 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
818 unsigned CPI = CPSections[i].CPEs[j];
819 MachineConstantPoolEntry CPE = CP[CPI];
821 // Emit inter-object padding for alignment.
822 unsigned AlignMask = CPE.getAlignment() - 1;
823 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
824 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/);
826 const Type *Ty = CPE.getType();
827 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
829 // Emit the label with a comment on it.
831 OutStreamer.GetCommentOS() << "constant pool ";
832 WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(),
833 MF->getFunction()->getParent());
834 OutStreamer.GetCommentOS() << '\n';
836 OutStreamer.EmitLabel(GetCPISymbol(CPI));
838 if (CPE.isMachineConstantPoolEntry())
839 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
841 EmitGlobalConstant(CPE.Val.ConstVal);
846 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
847 /// by the current function to the current output stream.
849 void AsmPrinter::EmitJumpTableInfo() {
850 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
851 if (MJTI == 0) return;
852 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
853 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
854 if (JT.empty()) return;
856 // Pick the directive to use to print the jump table entries, and switch to
857 // the appropriate section.
858 const Function *F = MF->getFunction();
859 bool JTInDiffSection = false;
860 if (// In PIC mode, we need to emit the jump table to the same section as the
861 // function body itself, otherwise the label differences won't make sense.
862 // FIXME: Need a better predicate for this: what about custom entries?
863 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
864 // We should also do if the section name is NULL or function is declared
865 // in discardable section
866 // FIXME: this isn't the right predicate, should be based on the MCSection
868 F->isWeakForLinker()) {
869 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
871 // Otherwise, drop it in the readonly section.
872 const MCSection *ReadOnlySection =
873 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
874 OutStreamer.SwitchSection(ReadOnlySection);
875 JTInDiffSection = true;
878 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData())));
880 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
881 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
883 // If this jump table was deleted, ignore it.
884 if (JTBBs.empty()) continue;
886 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
887 // .set directive for each unique entry. This reduces the number of
888 // relocations the assembler will generate for the jump table.
889 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
890 MAI->hasSetDirective()) {
891 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
892 const TargetLowering *TLI = TM.getTargetLowering();
893 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
894 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
895 const MachineBasicBlock *MBB = JTBBs[ii];
896 if (!EmittedSets.insert(MBB)) continue;
898 // .set LJTSet, LBB32-base
900 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
901 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
902 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
906 // On some targets (e.g. Darwin) we want to emit two consequtive labels
907 // before each jump table. The first label is never referenced, but tells
908 // the assembler and linker the extents of the jump table object. The
909 // second label is actually referenced by the code.
910 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
911 // FIXME: This doesn't have to have any specific name, just any randomly
912 // named and numbered 'l' label would work. Simplify GetJTISymbol.
913 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
915 OutStreamer.EmitLabel(GetJTISymbol(JTI));
917 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
918 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
922 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
924 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
925 const MachineBasicBlock *MBB,
926 unsigned UID) const {
927 const MCExpr *Value = 0;
928 switch (MJTI->getEntryKind()) {
929 case MachineJumpTableInfo::EK_Inline:
930 llvm_unreachable("Cannot emit EK_Inline jump table entry"); break;
931 case MachineJumpTableInfo::EK_Custom32:
932 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
935 case MachineJumpTableInfo::EK_BlockAddress:
936 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
938 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
940 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
941 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
942 // with a relocation as gp-relative, e.g.:
944 MCSymbol *MBBSym = MBB->getSymbol();
945 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
949 case MachineJumpTableInfo::EK_LabelDifference32: {
950 // EK_LabelDifference32 - Each entry is the address of the block minus
951 // the address of the jump table. This is used for PIC jump tables where
952 // gprel32 is not supported. e.g.:
953 // .word LBB123 - LJTI1_2
954 // If the .set directive is supported, this is emitted as:
955 // .set L4_5_set_123, LBB123 - LJTI1_2
956 // .word L4_5_set_123
958 // If we have emitted set directives for the jump table entries, print
959 // them rather than the entries themselves. If we're emitting PIC, then
960 // emit the table entries as differences between two text section labels.
961 if (MAI->hasSetDirective()) {
962 // If we used .set, reference the .set's symbol.
963 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
967 // Otherwise, use the difference as the jump table entry.
968 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
969 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
970 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
975 assert(Value && "Unknown entry kind!");
977 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData());
978 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0);
982 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
983 /// special global used by LLVM. If so, emit it and return true, otherwise
984 /// do nothing and return false.
985 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
986 if (GV->getName() == "llvm.used") {
987 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
988 EmitLLVMUsedList(GV->getInitializer());
992 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
993 if (GV->getSection() == "llvm.metadata" ||
994 GV->hasAvailableExternallyLinkage())
997 if (!GV->hasAppendingLinkage()) return false;
999 assert(GV->hasInitializer() && "Not a special LLVM global!");
1001 const TargetData *TD = TM.getTargetData();
1002 unsigned Align = Log2_32(TD->getPointerPrefAlignment());
1003 if (GV->getName() == "llvm.global_ctors") {
1004 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection());
1005 EmitAlignment(Align, 0);
1006 EmitXXStructorList(GV->getInitializer());
1008 if (TM.getRelocationModel() == Reloc::Static &&
1009 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1010 StringRef Sym(".constructors_used");
1011 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1017 if (GV->getName() == "llvm.global_dtors") {
1018 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection());
1019 EmitAlignment(Align, 0);
1020 EmitXXStructorList(GV->getInitializer());
1022 if (TM.getRelocationModel() == Reloc::Static &&
1023 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1024 StringRef Sym(".destructors_used");
1025 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1034 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1035 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1036 /// is true, as being used with this directive.
1037 void AsmPrinter::EmitLLVMUsedList(Constant *List) {
1038 // Should be an array of 'i8*'.
1039 ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1040 if (InitList == 0) return;
1042 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1043 const GlobalValue *GV =
1044 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1045 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
1046 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip);
1050 /// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the
1051 /// function pointers, ignoring the init priority.
1052 void AsmPrinter::EmitXXStructorList(Constant *List) {
1053 // Should be an array of '{ int, void ()* }' structs. The first value is the
1054 // init priority, which we ignore.
1055 if (!isa<ConstantArray>(List)) return;
1056 ConstantArray *InitList = cast<ConstantArray>(List);
1057 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
1058 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
1059 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs.
1061 if (CS->getOperand(1)->isNullValue())
1062 return; // Found a null terminator, exit printing.
1063 // Emit the function pointer.
1064 EmitGlobalConstant(CS->getOperand(1));
1068 //===--------------------------------------------------------------------===//
1069 // Emission and print routines
1072 /// EmitInt8 - Emit a byte directive and value.
1074 void AsmPrinter::EmitInt8(int Value) const {
1075 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/);
1078 /// EmitInt16 - Emit a short directive and value.
1080 void AsmPrinter::EmitInt16(int Value) const {
1081 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/);
1084 /// EmitInt32 - Emit a long directive and value.
1086 void AsmPrinter::EmitInt32(int Value) const {
1087 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/);
1090 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
1091 /// in bytes of the directive is specified by Size and Hi/Lo specify the
1092 /// labels. This implicitly uses .set if it is available.
1093 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1094 unsigned Size) const {
1095 // Get the Hi-Lo expression.
1096 const MCExpr *Diff =
1097 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1098 MCSymbolRefExpr::Create(Lo, OutContext),
1101 if (!MAI->hasSetDirective()) {
1102 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/);
1106 // Otherwise, emit with .set (aka assignment).
1107 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1108 OutStreamer.EmitAssignment(SetLabel, Diff);
1109 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/);
1112 /// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo"
1113 /// where the size in bytes of the directive is specified by Size and Hi/Lo
1114 /// specify the labels. This implicitly uses .set if it is available.
1115 void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset,
1116 const MCSymbol *Lo, unsigned Size)
1119 // Emit Hi+Offset - Lo
1120 // Get the Hi+Offset expression.
1121 const MCExpr *Plus =
1122 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext),
1123 MCConstantExpr::Create(Offset, OutContext),
1126 // Get the Hi+Offset-Lo expression.
1127 const MCExpr *Diff =
1128 MCBinaryExpr::CreateSub(Plus,
1129 MCSymbolRefExpr::Create(Lo, OutContext),
1132 if (!MAI->hasSetDirective())
1133 OutStreamer.EmitValue(Diff, 4, 0/*AddrSpace*/);
1135 // Otherwise, emit with .set (aka assignment).
1136 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1137 OutStreamer.EmitAssignment(SetLabel, Diff);
1138 OutStreamer.EmitSymbolValue(SetLabel, 4, 0/*AddrSpace*/);
1143 //===----------------------------------------------------------------------===//
1145 // EmitAlignment - Emit an alignment directive to the specified power of
1146 // two boundary. For example, if you pass in 3 here, you will get an 8
1147 // byte alignment. If a global value is specified, and if that global has
1148 // an explicit alignment requested, it will unconditionally override the
1149 // alignment request. However, if ForcedAlignBits is specified, this value
1150 // has final say: the ultimate alignment will be the max of ForcedAlignBits
1151 // and the alignment computed with NumBits and the global.
1153 // The algorithm is:
1155 // if (GV && GV->hasalignment) Align = GV->getalignment();
1156 // Align = std::max(Align, ForcedAlignBits);
1158 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
1159 unsigned ForcedAlignBits,
1160 bool UseFillExpr) const {
1161 if (GV && GV->getAlignment())
1162 NumBits = Log2_32(GV->getAlignment());
1163 NumBits = std::max(NumBits, ForcedAlignBits);
1165 if (NumBits == 0) return; // No need to emit alignment.
1167 if (getCurrentSection()->getKind().isText())
1168 OutStreamer.EmitCodeAlignment(1 << NumBits);
1170 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
1173 //===----------------------------------------------------------------------===//
1174 // Constant emission.
1175 //===----------------------------------------------------------------------===//
1177 /// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
1179 static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) {
1180 MCContext &Ctx = AP.OutContext;
1182 if (CV->isNullValue() || isa<UndefValue>(CV))
1183 return MCConstantExpr::Create(0, Ctx);
1185 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1186 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1188 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1189 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx);
1190 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1191 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1193 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1195 llvm_unreachable("Unknown constant value to lower!");
1196 return MCConstantExpr::Create(0, Ctx);
1199 switch (CE->getOpcode()) {
1201 // If the code isn't optimized, there may be outstanding folding
1202 // opportunities. Attempt to fold the expression using TargetData as a
1203 // last resort before giving up.
1205 ConstantFoldConstantExpression(CE, AP.TM.getTargetData()))
1207 return LowerConstant(C, AP);
1211 llvm_unreachable("FIXME: Don't support this constant expr");
1212 case Instruction::GetElementPtr: {
1213 const TargetData &TD = *AP.TM.getTargetData();
1214 // Generate a symbolic expression for the byte address
1215 const Constant *PtrVal = CE->getOperand(0);
1216 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
1217 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0],
1220 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
1224 // Truncate/sext the offset to the pointer size.
1225 if (TD.getPointerSizeInBits() != 64) {
1226 int SExtAmount = 64-TD.getPointerSizeInBits();
1227 Offset = (Offset << SExtAmount) >> SExtAmount;
1230 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1234 case Instruction::Trunc:
1235 // We emit the value and depend on the assembler to truncate the generated
1236 // expression properly. This is important for differences between
1237 // blockaddress labels. Since the two labels are in the same function, it
1238 // is reasonable to treat their delta as a 32-bit value.
1240 case Instruction::BitCast:
1241 return LowerConstant(CE->getOperand(0), AP);
1243 case Instruction::IntToPtr: {
1244 const TargetData &TD = *AP.TM.getTargetData();
1245 // Handle casts to pointers by changing them into casts to the appropriate
1246 // integer type. This promotes constant folding and simplifies this code.
1247 Constant *Op = CE->getOperand(0);
1248 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
1250 return LowerConstant(Op, AP);
1253 case Instruction::PtrToInt: {
1254 const TargetData &TD = *AP.TM.getTargetData();
1255 // Support only foldable casts to/from pointers that can be eliminated by
1256 // changing the pointer to the appropriately sized integer type.
1257 Constant *Op = CE->getOperand(0);
1258 const Type *Ty = CE->getType();
1260 const MCExpr *OpExpr = LowerConstant(Op, AP);
1262 // We can emit the pointer value into this slot if the slot is an
1263 // integer slot equal to the size of the pointer.
1264 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
1267 // Otherwise the pointer is smaller than the resultant integer, mask off
1268 // the high bits so we are sure to get a proper truncation if the input is
1270 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
1271 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1272 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1275 // The MC library also has a right-shift operator, but it isn't consistently
1276 // signed or unsigned between different targets.
1277 case Instruction::Add:
1278 case Instruction::Sub:
1279 case Instruction::Mul:
1280 case Instruction::SDiv:
1281 case Instruction::SRem:
1282 case Instruction::Shl:
1283 case Instruction::And:
1284 case Instruction::Or:
1285 case Instruction::Xor: {
1286 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP);
1287 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP);
1288 switch (CE->getOpcode()) {
1289 default: llvm_unreachable("Unknown binary operator constant cast expr");
1290 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1291 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1292 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1293 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1294 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1295 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1296 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1297 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1298 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1304 static void EmitGlobalConstantImpl(const Constant *C, unsigned AddrSpace,
1307 static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
1309 if (AddrSpace != 0 || !CA->isString()) {
1310 // Not a string. Print the values in successive locations
1311 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1312 EmitGlobalConstantImpl(CA->getOperand(i), AddrSpace, AP);
1316 // Otherwise, it can be emitted as .ascii.
1317 SmallVector<char, 128> TmpVec;
1318 TmpVec.reserve(CA->getNumOperands());
1319 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1320 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
1322 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace);
1325 static void EmitGlobalConstantVector(const ConstantVector *CV,
1326 unsigned AddrSpace, AsmPrinter &AP) {
1327 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1328 EmitGlobalConstantImpl(CV->getOperand(i), AddrSpace, AP);
1331 static void EmitGlobalConstantStruct(const ConstantStruct *CS,
1332 unsigned AddrSpace, AsmPrinter &AP) {
1333 // Print the fields in successive locations. Pad to align if needed!
1334 const TargetData *TD = AP.TM.getTargetData();
1335 unsigned Size = TD->getTypeAllocSize(CS->getType());
1336 const StructLayout *Layout = TD->getStructLayout(CS->getType());
1337 uint64_t SizeSoFar = 0;
1338 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1339 const Constant *Field = CS->getOperand(i);
1341 // Check if padding is needed and insert one or more 0s.
1342 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
1343 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1344 - Layout->getElementOffset(i)) - FieldSize;
1345 SizeSoFar += FieldSize + PadSize;
1347 // Now print the actual field value.
1348 EmitGlobalConstantImpl(Field, AddrSpace, AP);
1350 // Insert padding - this may include padding to increase the size of the
1351 // current field up to the ABI size (if the struct is not packed) as well
1352 // as padding to ensure that the next field starts at the right offset.
1353 AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
1355 assert(SizeSoFar == Layout->getSizeInBytes() &&
1356 "Layout of constant struct may be incorrect!");
1359 static void EmitGlobalConstantUnion(const ConstantUnion *CU,
1360 unsigned AddrSpace, AsmPrinter &AP) {
1361 const TargetData *TD = AP.TM.getTargetData();
1362 unsigned Size = TD->getTypeAllocSize(CU->getType());
1364 const Constant *Contents = CU->getOperand(0);
1365 unsigned FilledSize = TD->getTypeAllocSize(Contents->getType());
1367 // Print the actually filled part
1368 EmitGlobalConstantImpl(Contents, AddrSpace, AP);
1370 // And pad with enough zeroes
1371 AP.OutStreamer.EmitZeros(Size-FilledSize, AddrSpace);
1374 static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
1376 // FP Constants are printed as integer constants to avoid losing
1378 if (CFP->getType()->isDoubleTy()) {
1379 if (AP.isVerbose()) {
1380 double Val = CFP->getValueAPF().convertToDouble();
1381 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n';
1384 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1385 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1389 if (CFP->getType()->isFloatTy()) {
1390 if (AP.isVerbose()) {
1391 float Val = CFP->getValueAPF().convertToFloat();
1392 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n';
1394 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1395 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace);
1399 if (CFP->getType()->isX86_FP80Ty()) {
1400 // all long double variants are printed as hex
1401 // API needed to prevent premature destruction
1402 APInt API = CFP->getValueAPF().bitcastToAPInt();
1403 const uint64_t *p = API.getRawData();
1404 if (AP.isVerbose()) {
1405 // Convert to double so we can print the approximate val as a comment.
1406 APFloat DoubleVal = CFP->getValueAPF();
1408 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1410 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= "
1411 << DoubleVal.convertToDouble() << '\n';
1414 if (AP.TM.getTargetData()->isBigEndian()) {
1415 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1416 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1418 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1419 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1422 // Emit the tail padding for the long double.
1423 const TargetData &TD = *AP.TM.getTargetData();
1424 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
1425 TD.getTypeStoreSize(CFP->getType()), AddrSpace);
1429 assert(CFP->getType()->isPPC_FP128Ty() &&
1430 "Floating point constant type not handled");
1431 // All long double variants are printed as hex
1432 // API needed to prevent premature destruction.
1433 APInt API = CFP->getValueAPF().bitcastToAPInt();
1434 const uint64_t *p = API.getRawData();
1435 if (AP.TM.getTargetData()->isBigEndian()) {
1436 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1437 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1439 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1440 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1444 static void EmitGlobalConstantLargeInt(const ConstantInt *CI,
1445 unsigned AddrSpace, AsmPrinter &AP) {
1446 const TargetData *TD = AP.TM.getTargetData();
1447 unsigned BitWidth = CI->getBitWidth();
1448 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
1450 // We don't expect assemblers to support integer data directives
1451 // for more than 64 bits, so we emit the data in at most 64-bit
1452 // quantities at a time.
1453 const uint64_t *RawData = CI->getValue().getRawData();
1454 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1455 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1456 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1460 static void EmitGlobalConstantImpl(const Constant *CV, unsigned AddrSpace,
1462 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) {
1463 uint64_t Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType());
1464 return AP.OutStreamer.EmitZeros(Size, AddrSpace);
1467 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1468 unsigned Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType());
1475 AP.OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue());
1476 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1479 EmitGlobalConstantLargeInt(CI, AddrSpace, AP);
1484 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1485 return EmitGlobalConstantArray(CVA, AddrSpace, AP);
1487 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1488 return EmitGlobalConstantStruct(CVS, AddrSpace, AP);
1490 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1491 return EmitGlobalConstantFP(CFP, AddrSpace, AP);
1493 if (isa<ConstantPointerNull>(CV)) {
1494 unsigned Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType());
1495 AP.OutStreamer.EmitIntValue(0, Size, AddrSpace);
1499 if (const ConstantUnion *CVU = dyn_cast<ConstantUnion>(CV))
1500 return EmitGlobalConstantUnion(CVU, AddrSpace, AP);
1502 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1503 return EmitGlobalConstantVector(V, AddrSpace, AP);
1505 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1506 // thread the streamer with EmitValue.
1507 AP.OutStreamer.EmitValue(LowerConstant(CV, AP),
1508 AP.TM.getTargetData()->getTypeAllocSize(CV->getType()),
1512 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1513 void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1514 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1516 EmitGlobalConstantImpl(CV, AddrSpace, *this);
1517 else if (MAI->hasSubsectionsViaSymbols()) {
1518 // If the global has zero size, emit a single byte so that two labels don't
1519 // look like they are at the same location.
1520 OutStreamer.EmitIntValue(0, 1, AddrSpace);
1524 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1525 // Target doesn't support this yet!
1526 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1529 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1531 OS << '+' << Offset;
1532 else if (Offset < 0)
1536 //===----------------------------------------------------------------------===//
1537 // Symbol Lowering Routines.
1538 //===----------------------------------------------------------------------===//
1540 /// GetTempSymbol - Return the MCSymbol corresponding to the assembler
1541 /// temporary label with the specified stem and unique ID.
1542 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const {
1543 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) +
1547 /// GetTempSymbol - Return an assembler temporary label with the specified
1549 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const {
1550 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix())+
1555 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
1556 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
1559 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
1560 return MMI->getAddrLabelSymbol(BB);
1563 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1564 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1565 return OutContext.GetOrCreateSymbol
1566 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
1567 + "_" + Twine(CPID));
1570 /// GetJTISymbol - Return the symbol for the specified jump table entry.
1571 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1572 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
1575 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
1576 /// FIXME: privatize to AsmPrinter.
1577 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
1578 return OutContext.GetOrCreateSymbol
1579 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
1580 Twine(UID) + "_set_" + Twine(MBBID));
1583 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1584 /// global value name as its base, with the specified suffix, and where the
1585 /// symbol is forced to have private linkage if ForcePrivate is true.
1586 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1588 bool ForcePrivate) const {
1589 SmallString<60> NameStr;
1590 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1591 NameStr.append(Suffix.begin(), Suffix.end());
1592 return OutContext.GetOrCreateSymbol(NameStr.str());
1595 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
1597 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
1598 SmallString<60> NameStr;
1599 Mang->getNameWithPrefix(NameStr, Sym);
1600 return OutContext.GetOrCreateSymbol(NameStr.str());
1605 /// PrintParentLoopComment - Print comments about parent loops of this one.
1606 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1607 unsigned FunctionNumber) {
1608 if (Loop == 0) return;
1609 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
1610 OS.indent(Loop->getLoopDepth()*2)
1611 << "Parent Loop BB" << FunctionNumber << "_"
1612 << Loop->getHeader()->getNumber()
1613 << " Depth=" << Loop->getLoopDepth() << '\n';
1617 /// PrintChildLoopComment - Print comments about child loops within
1618 /// the loop for this basic block, with nesting.
1619 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1620 unsigned FunctionNumber) {
1621 // Add child loop information
1622 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
1623 OS.indent((*CL)->getLoopDepth()*2)
1624 << "Child Loop BB" << FunctionNumber << "_"
1625 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
1627 PrintChildLoopComment(OS, *CL, FunctionNumber);
1631 /// EmitBasicBlockLoopComments - Pretty-print comments for basic blocks.
1632 static void EmitBasicBlockLoopComments(const MachineBasicBlock &MBB,
1633 const MachineLoopInfo *LI,
1634 const AsmPrinter &AP) {
1635 // Add loop depth information
1636 const MachineLoop *Loop = LI->getLoopFor(&MBB);
1637 if (Loop == 0) return;
1639 MachineBasicBlock *Header = Loop->getHeader();
1640 assert(Header && "No header for loop");
1642 // If this block is not a loop header, just print out what is the loop header
1644 if (Header != &MBB) {
1645 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
1646 Twine(AP.getFunctionNumber())+"_" +
1647 Twine(Loop->getHeader()->getNumber())+
1648 " Depth="+Twine(Loop->getLoopDepth()));
1652 // Otherwise, it is a loop header. Print out information about child and
1654 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
1656 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
1659 OS.indent(Loop->getLoopDepth()*2-2);
1664 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
1666 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
1670 /// EmitBasicBlockStart - This method prints the label for the specified
1671 /// MachineBasicBlock, an alignment (if present) and a comment describing
1672 /// it if appropriate.
1673 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
1674 // Emit an alignment directive for this block, if needed.
1675 if (unsigned Align = MBB->getAlignment())
1676 EmitAlignment(Log2_32(Align));
1678 // If the block has its address taken, emit any labels that were used to
1679 // reference the block. It is possible that there is more than one label
1680 // here, because multiple LLVM BB's may have been RAUW'd to this block after
1681 // the references were generated.
1682 if (MBB->hasAddressTaken()) {
1683 const BasicBlock *BB = MBB->getBasicBlock();
1685 OutStreamer.AddComment("Block address taken");
1687 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
1689 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
1690 OutStreamer.EmitLabel(Syms[i]);
1693 // Print the main label for the block.
1694 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
1695 if (isVerbose() && OutStreamer.hasRawTextSupport()) {
1696 if (const BasicBlock *BB = MBB->getBasicBlock())
1698 OutStreamer.AddComment("%" + BB->getName());
1700 EmitBasicBlockLoopComments(*MBB, LI, *this);
1702 // NOTE: Want this comment at start of line, don't emit with AddComment.
1703 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" +
1704 Twine(MBB->getNumber()) + ":");
1708 if (const BasicBlock *BB = MBB->getBasicBlock())
1710 OutStreamer.AddComment("%" + BB->getName());
1711 EmitBasicBlockLoopComments(*MBB, LI, *this);
1714 OutStreamer.EmitLabel(MBB->getSymbol());
1718 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility) const {
1719 MCSymbolAttr Attr = MCSA_Invalid;
1721 switch (Visibility) {
1723 case GlobalValue::HiddenVisibility:
1724 Attr = MAI->getHiddenVisibilityAttr();
1726 case GlobalValue::ProtectedVisibility:
1727 Attr = MAI->getProtectedVisibilityAttr();
1731 if (Attr != MCSA_Invalid)
1732 OutStreamer.EmitSymbolAttribute(Sym, Attr);
1735 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
1736 /// exactly one predecessor and the control transfer mechanism between
1737 /// the predecessor and this block is a fall-through.
1739 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
1740 // If this is a landing pad, it isn't a fall through. If it has no preds,
1741 // then nothing falls through to it.
1742 if (MBB->isLandingPad() || MBB->pred_empty())
1745 // If there isn't exactly one predecessor, it can't be a fall through.
1746 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
1748 if (PI2 != MBB->pred_end())
1751 // The predecessor has to be immediately before this block.
1752 const MachineBasicBlock *Pred = *PI;
1754 if (!Pred->isLayoutSuccessor(MBB))
1757 // If the block is completely empty, then it definitely does fall through.
1761 // Otherwise, check the last instruction.
1762 const MachineInstr &LastInst = Pred->back();
1763 return !LastInst.getDesc().isBarrier();
1768 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1769 if (!S->usesMetadata())
1772 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
1773 gcp_map_type::iterator GCPI = GCMap.find(S);
1774 if (GCPI != GCMap.end())
1775 return GCPI->second;
1777 const char *Name = S->getName().c_str();
1779 for (GCMetadataPrinterRegistry::iterator
1780 I = GCMetadataPrinterRegistry::begin(),
1781 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1782 if (strcmp(Name, I->getName()) == 0) {
1783 GCMetadataPrinter *GMP = I->instantiate();
1785 GCMap.insert(std::make_pair(S, GMP));
1789 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));