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 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());
231 unsigned AlignLog = TD->getPreferredAlignmentLog(GV);
233 // Handle common and BSS local symbols (.lcomm).
234 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
235 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
238 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
239 /*PrintType=*/false, GV->getParent());
240 OutStreamer.GetCommentOS() << '\n';
243 // Handle common symbols.
244 if (GVKind.isCommon()) {
246 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
250 // Handle local BSS symbols.
251 if (MAI->hasMachoZeroFillDirective()) {
252 const MCSection *TheSection =
253 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
254 // .zerofill __DATA, __bss, _foo, 400, 5
255 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
259 if (MAI->hasLCOMMDirective()) {
261 OutStreamer.EmitLocalCommonSymbol(GVSym, Size);
266 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
268 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
272 const MCSection *TheSection =
273 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
275 // Handle the zerofill directive on darwin, which is a special form of BSS
277 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
279 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
280 // .zerofill __DATA, __common, _foo, 400, 5
281 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
285 OutStreamer.SwitchSection(TheSection);
287 EmitLinkage(GV->getLinkage(), GVSym);
288 EmitAlignment(AlignLog, GV);
291 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
292 /*PrintType=*/false, GV->getParent());
293 OutStreamer.GetCommentOS() << '\n';
295 OutStreamer.EmitLabel(GVSym);
297 EmitGlobalConstant(GV->getInitializer());
299 if (MAI->hasDotTypeDotSizeDirective())
301 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
303 OutStreamer.AddBlankLine();
306 /// EmitFunctionHeader - This method emits the header for the current
308 void AsmPrinter::EmitFunctionHeader() {
309 // Print out constants referenced by the function
312 // Print the 'header' of function.
313 const Function *F = MF->getFunction();
315 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
316 EmitVisibility(CurrentFnSym, F->getVisibility());
318 EmitLinkage(F->getLinkage(), CurrentFnSym);
319 EmitAlignment(MF->getAlignment(), F);
321 if (MAI->hasDotTypeDotSizeDirective())
322 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
325 WriteAsOperand(OutStreamer.GetCommentOS(), F,
326 /*PrintType=*/false, F->getParent());
327 OutStreamer.GetCommentOS() << '\n';
330 // Emit the CurrentFnSym. This is a virtual function to allow targets to
331 // do their wild and crazy things as required.
332 EmitFunctionEntryLabel();
334 // If the function had address-taken blocks that got deleted, then we have
335 // references to the dangling symbols. Emit them at the start of the function
336 // so that we don't get references to undefined symbols.
337 std::vector<MCSymbol*> DeadBlockSyms;
338 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
339 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
340 OutStreamer.AddComment("Address taken block that was later removed");
341 OutStreamer.EmitLabel(DeadBlockSyms[i]);
344 // Add some workaround for linkonce linkage on Cygwin\MinGW.
345 if (MAI->getLinkOnceDirective() != 0 &&
346 (F->hasLinkOnceLinkage() || F->hasWeakLinkage())) {
347 // FIXME: What is this?
349 OutContext.GetOrCreateSymbol(Twine("Lllvm$workaround$fake$stub$")+
350 CurrentFnSym->getName());
351 OutStreamer.EmitLabel(FakeStub);
354 // Emit pre-function debug and/or EH information.
356 if (TimePassesIsEnabled) {
357 NamedRegionTimer T(EHTimerName, DWARFGroupName);
358 DE->BeginFunction(MF);
360 DE->BeginFunction(MF);
364 if (TimePassesIsEnabled) {
365 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
366 DD->beginFunction(MF);
368 DD->beginFunction(MF);
373 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
374 /// function. This can be overridden by targets as required to do custom stuff.
375 void AsmPrinter::EmitFunctionEntryLabel() {
376 OutStreamer.EmitLabel(CurrentFnSym);
380 /// EmitComments - Pretty-print comments for instructions.
381 static void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
382 const MachineFunction *MF = MI.getParent()->getParent();
383 const TargetMachine &TM = MF->getTarget();
385 DebugLoc DL = MI.getDebugLoc();
386 if (!DL.isUnknown()) { // Print source line info.
387 DIScope Scope(DL.getScope(MF->getFunction()->getContext()));
388 // Omit the directory, because it's likely to be long and uninteresting.
390 CommentOS << Scope.getFilename();
392 CommentOS << "<unknown>";
393 CommentOS << ':' << DL.getLine();
394 if (DL.getCol() != 0)
395 CommentOS << ':' << DL.getCol();
399 // Check for spills and reloads
402 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
404 // We assume a single instruction only has a spill or reload, not
406 const MachineMemOperand *MMO;
407 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
408 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
409 MMO = *MI.memoperands_begin();
410 CommentOS << MMO->getSize() << "-byte Reload\n";
412 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
413 if (FrameInfo->isSpillSlotObjectIndex(FI))
414 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
415 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
416 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
417 MMO = *MI.memoperands_begin();
418 CommentOS << MMO->getSize() << "-byte Spill\n";
420 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
421 if (FrameInfo->isSpillSlotObjectIndex(FI))
422 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
425 // Check for spill-induced copies
426 unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
427 if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg,
428 SrcSubIdx, DstSubIdx)) {
429 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
430 CommentOS << " Reload Reuse\n";
434 /// EmitImplicitDef - This method emits the specified machine instruction
435 /// that is an implicit def.
436 static void EmitImplicitDef(const MachineInstr *MI, AsmPrinter &AP) {
437 unsigned RegNo = MI->getOperand(0).getReg();
438 AP.OutStreamer.AddComment(Twine("implicit-def: ") +
439 AP.TM.getRegisterInfo()->getName(RegNo));
440 AP.OutStreamer.AddBlankLine();
443 static void EmitKill(const MachineInstr *MI, AsmPrinter &AP) {
444 std::string Str = "kill:";
445 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
446 const MachineOperand &Op = MI->getOperand(i);
447 assert(Op.isReg() && "KILL instruction must have only register operands");
449 Str += AP.TM.getRegisterInfo()->getName(Op.getReg());
450 Str += (Op.isDef() ? "<def>" : "<kill>");
452 AP.OutStreamer.AddComment(Str);
453 AP.OutStreamer.AddBlankLine();
456 /// EmitDebugValueComment - This method handles the target-independent form
457 /// of DBG_VALUE, returning true if it was able to do so. A false return
458 /// means the target will need to handle MI in EmitInstruction.
459 static bool EmitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
460 // This code handles only the 3-operand target-independent form.
461 if (MI->getNumOperands() != 3)
464 SmallString<128> Str;
465 raw_svector_ostream OS(Str);
466 OS << '\t' << AP.MAI->getCommentString() << "DEBUG_VALUE: ";
468 // cast away const; DIetc do not take const operands for some reason.
469 DIVariable V(const_cast<MDNode*>(MI->getOperand(2).getMetadata()));
470 OS << V.getName() << " <- ";
472 // Register or immediate value. Register 0 means undef.
473 if (MI->getOperand(0).isFPImm()) {
474 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
475 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
476 OS << (double)APF.convertToFloat();
477 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
478 OS << APF.convertToDouble();
480 // There is no good way to print long double. Convert a copy to
481 // double. Ah well, it's only a comment.
483 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
485 OS << "(long double) " << APF.convertToDouble();
487 } else if (MI->getOperand(0).isImm()) {
488 OS << MI->getOperand(0).getImm();
490 assert(MI->getOperand(0).isReg() && "Unknown operand type");
491 if (MI->getOperand(0).getReg() == 0) {
492 // Suppress offset, it is not meaningful here.
494 // NOTE: Want this comment at start of line, don't emit with AddComment.
495 AP.OutStreamer.EmitRawText(OS.str());
498 OS << AP.TM.getRegisterInfo()->getName(MI->getOperand(0).getReg());
501 OS << '+' << MI->getOperand(1).getImm();
502 // NOTE: Want this comment at start of line, don't emit with AddComment.
503 AP.OutStreamer.EmitRawText(OS.str());
507 /// EmitFunctionBody - This method emits the body and trailer for a
509 void AsmPrinter::EmitFunctionBody() {
510 // Emit target-specific gunk before the function body.
511 EmitFunctionBodyStart();
513 bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo();
515 // Print out code for the function.
516 bool HasAnyRealCode = false;
517 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
519 // Print a label for the basic block.
520 EmitBasicBlockStart(I);
521 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
523 // Print the assembly for the instruction.
525 HasAnyRealCode = true;
529 if (ShouldPrintDebugScopes) {
530 if (TimePassesIsEnabled) {
531 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
539 EmitComments(*II, OutStreamer.GetCommentOS());
541 switch (II->getOpcode()) {
542 case TargetOpcode::DBG_LABEL:
543 case TargetOpcode::EH_LABEL:
544 case TargetOpcode::GC_LABEL:
545 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol());
547 case TargetOpcode::INLINEASM:
550 case TargetOpcode::DBG_VALUE:
552 if (!EmitDebugValueComment(II, *this))
556 case TargetOpcode::IMPLICIT_DEF:
557 if (isVerbose()) EmitImplicitDef(II, *this);
559 case TargetOpcode::KILL:
560 if (isVerbose()) EmitKill(II, *this);
567 if (ShouldPrintDebugScopes) {
568 if (TimePassesIsEnabled) {
569 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
578 // If the function is empty and the object file uses .subsections_via_symbols,
579 // then we need to emit *something* to the function body to prevent the
580 // labels from collapsing together. Just emit a 0 byte.
581 if (MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)
582 OutStreamer.EmitIntValue(0, 1, 0/*addrspace*/);
584 // Emit target-specific gunk after the function body.
585 EmitFunctionBodyEnd();
587 // If the target wants a .size directive for the size of the function, emit
589 if (MAI->hasDotTypeDotSizeDirective()) {
590 // Create a symbol for the end of function, so we can get the size as
591 // difference between the function label and the temp label.
592 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
593 OutStreamer.EmitLabel(FnEndLabel);
595 const MCExpr *SizeExp =
596 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
597 MCSymbolRefExpr::Create(CurrentFnSym, OutContext),
599 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
602 // Emit post-function debug information.
604 if (TimePassesIsEnabled) {
605 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
612 if (TimePassesIsEnabled) {
613 NamedRegionTimer T(EHTimerName, DWARFGroupName);
621 // Print out jump tables referenced by the function.
624 OutStreamer.AddBlankLine();
628 bool AsmPrinter::doFinalization(Module &M) {
629 // Emit global variables.
630 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
632 EmitGlobalVariable(I);
634 // Finalize debug and EH information.
636 if (TimePassesIsEnabled) {
637 NamedRegionTimer T(EHTimerName, DWARFGroupName);
645 if (TimePassesIsEnabled) {
646 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
654 // If the target wants to know about weak references, print them all.
655 if (MAI->getWeakRefDirective()) {
656 // FIXME: This is not lazy, it would be nice to only print weak references
657 // to stuff that is actually used. Note that doing so would require targets
658 // to notice uses in operands (due to constant exprs etc). This should
659 // happen with the MC stuff eventually.
661 // Print out module-level global variables here.
662 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
664 if (!I->hasExternalWeakLinkage()) continue;
665 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
668 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
669 if (!I->hasExternalWeakLinkage()) continue;
670 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
674 if (MAI->hasSetDirective()) {
675 OutStreamer.AddBlankLine();
676 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
678 MCSymbol *Name = Mang->getSymbol(I);
680 const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
681 MCSymbol *Target = Mang->getSymbol(GV);
683 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
684 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
685 else if (I->hasWeakLinkage())
686 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
688 assert(I->hasLocalLinkage() && "Invalid alias linkage");
690 EmitVisibility(Name, I->getVisibility());
692 // Emit the directives as assignments aka .set:
693 OutStreamer.EmitAssignment(Name,
694 MCSymbolRefExpr::Create(Target, OutContext));
698 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
699 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
700 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
701 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
702 MP->finishAssembly(*this);
704 // If we don't have any trampolines, then we don't require stack memory
705 // to be executable. Some targets have a directive to declare this.
706 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
707 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
708 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext))
709 OutStreamer.SwitchSection(S);
711 // Allow the target to emit any magic that it wants at the end of the file,
712 // after everything else has gone out.
715 delete Mang; Mang = 0;
718 OutStreamer.Finish();
722 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
724 // Get the function symbol.
725 CurrentFnSym = Mang->getSymbol(MF.getFunction());
728 LI = &getAnalysis<MachineLoopInfo>();
732 // SectionCPs - Keep track the alignment, constpool entries per Section.
736 SmallVector<unsigned, 4> CPEs;
737 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
741 /// EmitConstantPool - Print to the current output stream assembly
742 /// representations of the constants in the constant pool MCP. This is
743 /// used to print out constants which have been "spilled to memory" by
744 /// the code generator.
746 void AsmPrinter::EmitConstantPool() {
747 const MachineConstantPool *MCP = MF->getConstantPool();
748 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
749 if (CP.empty()) return;
751 // Calculate sections for constant pool entries. We collect entries to go into
752 // the same section together to reduce amount of section switch statements.
753 SmallVector<SectionCPs, 4> CPSections;
754 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
755 const MachineConstantPoolEntry &CPE = CP[i];
756 unsigned Align = CPE.getAlignment();
759 switch (CPE.getRelocationInfo()) {
760 default: llvm_unreachable("Unknown section kind");
761 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
763 Kind = SectionKind::getReadOnlyWithRelLocal();
766 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
767 case 4: Kind = SectionKind::getMergeableConst4(); break;
768 case 8: Kind = SectionKind::getMergeableConst8(); break;
769 case 16: Kind = SectionKind::getMergeableConst16();break;
770 default: Kind = SectionKind::getMergeableConst(); break;
774 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
776 // The number of sections are small, just do a linear search from the
777 // last section to the first.
779 unsigned SecIdx = CPSections.size();
780 while (SecIdx != 0) {
781 if (CPSections[--SecIdx].S == S) {
787 SecIdx = CPSections.size();
788 CPSections.push_back(SectionCPs(S, Align));
791 if (Align > CPSections[SecIdx].Alignment)
792 CPSections[SecIdx].Alignment = Align;
793 CPSections[SecIdx].CPEs.push_back(i);
796 // Now print stuff into the calculated sections.
797 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
798 OutStreamer.SwitchSection(CPSections[i].S);
799 EmitAlignment(Log2_32(CPSections[i].Alignment));
802 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
803 unsigned CPI = CPSections[i].CPEs[j];
804 MachineConstantPoolEntry CPE = CP[CPI];
806 // Emit inter-object padding for alignment.
807 unsigned AlignMask = CPE.getAlignment() - 1;
808 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
809 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/);
811 const Type *Ty = CPE.getType();
812 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
814 // Emit the label with a comment on it.
816 OutStreamer.GetCommentOS() << "constant pool ";
817 WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(),
818 MF->getFunction()->getParent());
819 OutStreamer.GetCommentOS() << '\n';
821 OutStreamer.EmitLabel(GetCPISymbol(CPI));
823 if (CPE.isMachineConstantPoolEntry())
824 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
826 EmitGlobalConstant(CPE.Val.ConstVal);
831 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
832 /// by the current function to the current output stream.
834 void AsmPrinter::EmitJumpTableInfo() {
835 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
836 if (MJTI == 0) return;
837 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
838 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
839 if (JT.empty()) return;
841 // Pick the directive to use to print the jump table entries, and switch to
842 // the appropriate section.
843 const Function *F = MF->getFunction();
844 bool JTInDiffSection = false;
845 if (// In PIC mode, we need to emit the jump table to the same section as the
846 // function body itself, otherwise the label differences won't make sense.
847 // FIXME: Need a better predicate for this: what about custom entries?
848 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
849 // We should also do if the section name is NULL or function is declared
850 // in discardable section
851 // FIXME: this isn't the right predicate, should be based on the MCSection
853 F->isWeakForLinker()) {
854 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
856 // Otherwise, drop it in the readonly section.
857 const MCSection *ReadOnlySection =
858 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
859 OutStreamer.SwitchSection(ReadOnlySection);
860 JTInDiffSection = true;
863 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData())));
865 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
866 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
868 // If this jump table was deleted, ignore it.
869 if (JTBBs.empty()) continue;
871 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
872 // .set directive for each unique entry. This reduces the number of
873 // relocations the assembler will generate for the jump table.
874 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
875 MAI->hasSetDirective()) {
876 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
877 const TargetLowering *TLI = TM.getTargetLowering();
878 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
879 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
880 const MachineBasicBlock *MBB = JTBBs[ii];
881 if (!EmittedSets.insert(MBB)) continue;
883 // .set LJTSet, LBB32-base
885 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
886 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
887 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
891 // On some targets (e.g. Darwin) we want to emit two consequtive labels
892 // before each jump table. The first label is never referenced, but tells
893 // the assembler and linker the extents of the jump table object. The
894 // second label is actually referenced by the code.
895 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
896 // FIXME: This doesn't have to have any specific name, just any randomly
897 // named and numbered 'l' label would work. Simplify GetJTISymbol.
898 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
900 OutStreamer.EmitLabel(GetJTISymbol(JTI));
902 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
903 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
907 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
909 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
910 const MachineBasicBlock *MBB,
911 unsigned UID) const {
912 const MCExpr *Value = 0;
913 switch (MJTI->getEntryKind()) {
914 case MachineJumpTableInfo::EK_Inline:
915 llvm_unreachable("Cannot emit EK_Inline jump table entry"); break;
916 case MachineJumpTableInfo::EK_Custom32:
917 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
920 case MachineJumpTableInfo::EK_BlockAddress:
921 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
923 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
925 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
926 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
927 // with a relocation as gp-relative, e.g.:
929 MCSymbol *MBBSym = MBB->getSymbol();
930 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
934 case MachineJumpTableInfo::EK_LabelDifference32: {
935 // EK_LabelDifference32 - Each entry is the address of the block minus
936 // the address of the jump table. This is used for PIC jump tables where
937 // gprel32 is not supported. e.g.:
938 // .word LBB123 - LJTI1_2
939 // If the .set directive is supported, this is emitted as:
940 // .set L4_5_set_123, LBB123 - LJTI1_2
941 // .word L4_5_set_123
943 // If we have emitted set directives for the jump table entries, print
944 // them rather than the entries themselves. If we're emitting PIC, then
945 // emit the table entries as differences between two text section labels.
946 if (MAI->hasSetDirective()) {
947 // If we used .set, reference the .set's symbol.
948 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
952 // Otherwise, use the difference as the jump table entry.
953 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
954 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
955 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
960 assert(Value && "Unknown entry kind!");
962 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData());
963 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0);
967 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
968 /// special global used by LLVM. If so, emit it and return true, otherwise
969 /// do nothing and return false.
970 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
971 if (GV->getName() == "llvm.used") {
972 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
973 EmitLLVMUsedList(GV->getInitializer());
977 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
978 if (GV->getSection() == "llvm.metadata" ||
979 GV->hasAvailableExternallyLinkage())
982 if (!GV->hasAppendingLinkage()) return false;
984 assert(GV->hasInitializer() && "Not a special LLVM global!");
986 const TargetData *TD = TM.getTargetData();
987 unsigned Align = Log2_32(TD->getPointerPrefAlignment());
988 if (GV->getName() == "llvm.global_ctors") {
989 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection());
990 EmitAlignment(Align, 0);
991 EmitXXStructorList(GV->getInitializer());
993 if (TM.getRelocationModel() == Reloc::Static &&
994 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
995 StringRef Sym(".constructors_used");
996 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1002 if (GV->getName() == "llvm.global_dtors") {
1003 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection());
1004 EmitAlignment(Align, 0);
1005 EmitXXStructorList(GV->getInitializer());
1007 if (TM.getRelocationModel() == Reloc::Static &&
1008 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1009 StringRef Sym(".destructors_used");
1010 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1019 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1020 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1021 /// is true, as being used with this directive.
1022 void AsmPrinter::EmitLLVMUsedList(Constant *List) {
1023 // Should be an array of 'i8*'.
1024 ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1025 if (InitList == 0) return;
1027 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1028 const GlobalValue *GV =
1029 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1030 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
1031 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip);
1035 /// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the
1036 /// function pointers, ignoring the init priority.
1037 void AsmPrinter::EmitXXStructorList(Constant *List) {
1038 // Should be an array of '{ int, void ()* }' structs. The first value is the
1039 // init priority, which we ignore.
1040 if (!isa<ConstantArray>(List)) return;
1041 ConstantArray *InitList = cast<ConstantArray>(List);
1042 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
1043 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
1044 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs.
1046 if (CS->getOperand(1)->isNullValue())
1047 return; // Found a null terminator, exit printing.
1048 // Emit the function pointer.
1049 EmitGlobalConstant(CS->getOperand(1));
1053 //===--------------------------------------------------------------------===//
1054 // Emission and print routines
1057 /// EmitInt8 - Emit a byte directive and value.
1059 void AsmPrinter::EmitInt8(int Value) const {
1060 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/);
1063 /// EmitInt16 - Emit a short directive and value.
1065 void AsmPrinter::EmitInt16(int Value) const {
1066 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/);
1069 /// EmitInt32 - Emit a long directive and value.
1071 void AsmPrinter::EmitInt32(int Value) const {
1072 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/);
1075 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
1076 /// in bytes of the directive is specified by Size and Hi/Lo specify the
1077 /// labels. This implicitly uses .set if it is available.
1078 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1079 unsigned Size) const {
1080 // Get the Hi-Lo expression.
1081 const MCExpr *Diff =
1082 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1083 MCSymbolRefExpr::Create(Lo, OutContext),
1086 if (!MAI->hasSetDirective()) {
1087 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/);
1091 // Otherwise, emit with .set (aka assignment).
1092 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1093 OutStreamer.EmitAssignment(SetLabel, Diff);
1094 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/);
1097 /// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo"
1098 /// where the size in bytes of the directive is specified by Size and Hi/Lo
1099 /// specify the labels. This implicitly uses .set if it is available.
1100 void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset,
1101 const MCSymbol *Lo, unsigned Size)
1104 // Emit Hi+Offset - Lo
1105 // Get the Hi+Offset expression.
1106 const MCExpr *Plus =
1107 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext),
1108 MCConstantExpr::Create(Offset, OutContext),
1111 // Get the Hi+Offset-Lo expression.
1112 const MCExpr *Diff =
1113 MCBinaryExpr::CreateSub(Plus,
1114 MCSymbolRefExpr::Create(Lo, OutContext),
1117 if (!MAI->hasSetDirective())
1118 OutStreamer.EmitValue(Diff, 4, 0/*AddrSpace*/);
1120 // Otherwise, emit with .set (aka assignment).
1121 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1122 OutStreamer.EmitAssignment(SetLabel, Diff);
1123 OutStreamer.EmitSymbolValue(SetLabel, 4, 0/*AddrSpace*/);
1128 //===----------------------------------------------------------------------===//
1130 // EmitAlignment - Emit an alignment directive to the specified power of
1131 // two boundary. For example, if you pass in 3 here, you will get an 8
1132 // byte alignment. If a global value is specified, and if that global has
1133 // an explicit alignment requested, it will unconditionally override the
1134 // alignment request. However, if ForcedAlignBits is specified, this value
1135 // has final say: the ultimate alignment will be the max of ForcedAlignBits
1136 // and the alignment computed with NumBits and the global.
1138 // The algorithm is:
1140 // if (GV && GV->hasalignment) Align = GV->getalignment();
1141 // Align = std::max(Align, ForcedAlignBits);
1143 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
1144 unsigned ForcedAlignBits,
1145 bool UseFillExpr) const {
1146 if (GV && GV->getAlignment())
1147 NumBits = Log2_32(GV->getAlignment());
1148 NumBits = std::max(NumBits, ForcedAlignBits);
1150 if (NumBits == 0) return; // No need to emit alignment.
1152 if (getCurrentSection()->getKind().isText())
1153 OutStreamer.EmitCodeAlignment(1 << NumBits);
1155 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
1158 /// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
1160 static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) {
1161 MCContext &Ctx = AP.OutContext;
1163 if (CV->isNullValue() || isa<UndefValue>(CV))
1164 return MCConstantExpr::Create(0, Ctx);
1166 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1167 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1169 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1170 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx);
1171 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1172 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1174 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1176 llvm_unreachable("Unknown constant value to lower!");
1177 return MCConstantExpr::Create(0, Ctx);
1180 switch (CE->getOpcode()) {
1182 // If the code isn't optimized, there may be outstanding folding
1183 // opportunities. Attempt to fold the expression using TargetData as a
1184 // last resort before giving up.
1186 ConstantFoldConstantExpression(CE, AP.TM.getTargetData()))
1188 return LowerConstant(C, AP);
1192 llvm_unreachable("FIXME: Don't support this constant expr");
1193 case Instruction::GetElementPtr: {
1194 const TargetData &TD = *AP.TM.getTargetData();
1195 // Generate a symbolic expression for the byte address
1196 const Constant *PtrVal = CE->getOperand(0);
1197 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
1198 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0],
1201 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
1205 // Truncate/sext the offset to the pointer size.
1206 if (TD.getPointerSizeInBits() != 64) {
1207 int SExtAmount = 64-TD.getPointerSizeInBits();
1208 Offset = (Offset << SExtAmount) >> SExtAmount;
1211 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1215 case Instruction::Trunc:
1216 // We emit the value and depend on the assembler to truncate the generated
1217 // expression properly. This is important for differences between
1218 // blockaddress labels. Since the two labels are in the same function, it
1219 // is reasonable to treat their delta as a 32-bit value.
1221 case Instruction::BitCast:
1222 return LowerConstant(CE->getOperand(0), AP);
1224 case Instruction::IntToPtr: {
1225 const TargetData &TD = *AP.TM.getTargetData();
1226 // Handle casts to pointers by changing them into casts to the appropriate
1227 // integer type. This promotes constant folding and simplifies this code.
1228 Constant *Op = CE->getOperand(0);
1229 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
1231 return LowerConstant(Op, AP);
1234 case Instruction::PtrToInt: {
1235 const TargetData &TD = *AP.TM.getTargetData();
1236 // Support only foldable casts to/from pointers that can be eliminated by
1237 // changing the pointer to the appropriately sized integer type.
1238 Constant *Op = CE->getOperand(0);
1239 const Type *Ty = CE->getType();
1241 const MCExpr *OpExpr = LowerConstant(Op, AP);
1243 // We can emit the pointer value into this slot if the slot is an
1244 // integer slot equal to the size of the pointer.
1245 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
1248 // Otherwise the pointer is smaller than the resultant integer, mask off
1249 // the high bits so we are sure to get a proper truncation if the input is
1251 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
1252 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1253 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1256 // The MC library also has a right-shift operator, but it isn't consistently
1257 // signed or unsigned between different targets.
1258 case Instruction::Add:
1259 case Instruction::Sub:
1260 case Instruction::Mul:
1261 case Instruction::SDiv:
1262 case Instruction::SRem:
1263 case Instruction::Shl:
1264 case Instruction::And:
1265 case Instruction::Or:
1266 case Instruction::Xor: {
1267 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP);
1268 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP);
1269 switch (CE->getOpcode()) {
1270 default: llvm_unreachable("Unknown binary operator constant cast expr");
1271 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1272 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1273 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1274 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1275 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1276 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1277 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1278 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1279 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1285 static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
1287 if (AddrSpace != 0 || !CA->isString()) {
1288 // Not a string. Print the values in successive locations
1289 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1290 AP.EmitGlobalConstant(CA->getOperand(i), AddrSpace);
1294 // Otherwise, it can be emitted as .ascii.
1295 SmallVector<char, 128> TmpVec;
1296 TmpVec.reserve(CA->getNumOperands());
1297 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1298 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
1300 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace);
1303 static void EmitGlobalConstantVector(const ConstantVector *CV,
1304 unsigned AddrSpace, AsmPrinter &AP) {
1305 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1306 AP.EmitGlobalConstant(CV->getOperand(i), AddrSpace);
1309 static void EmitGlobalConstantStruct(const ConstantStruct *CS,
1310 unsigned AddrSpace, AsmPrinter &AP) {
1311 // Print the fields in successive locations. Pad to align if needed!
1312 const TargetData *TD = AP.TM.getTargetData();
1313 unsigned Size = TD->getTypeAllocSize(CS->getType());
1314 const StructLayout *Layout = TD->getStructLayout(CS->getType());
1315 uint64_t SizeSoFar = 0;
1316 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1317 const Constant *Field = CS->getOperand(i);
1319 // Check if padding is needed and insert one or more 0s.
1320 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
1321 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1322 - Layout->getElementOffset(i)) - FieldSize;
1323 SizeSoFar += FieldSize + PadSize;
1325 // Now print the actual field value.
1326 AP.EmitGlobalConstant(Field, AddrSpace);
1328 // Insert padding - this may include padding to increase the size of the
1329 // current field up to the ABI size (if the struct is not packed) as well
1330 // as padding to ensure that the next field starts at the right offset.
1331 AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
1333 assert(SizeSoFar == Layout->getSizeInBytes() &&
1334 "Layout of constant struct may be incorrect!");
1337 static void EmitGlobalConstantUnion(const ConstantUnion *CU,
1338 unsigned AddrSpace, AsmPrinter &AP) {
1339 const TargetData *TD = AP.TM.getTargetData();
1340 unsigned Size = TD->getTypeAllocSize(CU->getType());
1342 const Constant *Contents = CU->getOperand(0);
1343 unsigned FilledSize = TD->getTypeAllocSize(Contents->getType());
1345 // Print the actually filled part
1346 AP.EmitGlobalConstant(Contents, AddrSpace);
1348 // And pad with enough zeroes
1349 AP.OutStreamer.EmitZeros(Size-FilledSize, AddrSpace);
1352 static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
1354 // FP Constants are printed as integer constants to avoid losing
1356 if (CFP->getType()->isDoubleTy()) {
1357 if (AP.isVerbose()) {
1358 double Val = CFP->getValueAPF().convertToDouble();
1359 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n';
1362 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1363 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1367 if (CFP->getType()->isFloatTy()) {
1368 if (AP.isVerbose()) {
1369 float Val = CFP->getValueAPF().convertToFloat();
1370 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n';
1372 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1373 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace);
1377 if (CFP->getType()->isX86_FP80Ty()) {
1378 // all long double variants are printed as hex
1379 // API needed to prevent premature destruction
1380 APInt API = CFP->getValueAPF().bitcastToAPInt();
1381 const uint64_t *p = API.getRawData();
1382 if (AP.isVerbose()) {
1383 // Convert to double so we can print the approximate val as a comment.
1384 APFloat DoubleVal = CFP->getValueAPF();
1386 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1388 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= "
1389 << DoubleVal.convertToDouble() << '\n';
1392 if (AP.TM.getTargetData()->isBigEndian()) {
1393 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1394 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1396 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1397 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1400 // Emit the tail padding for the long double.
1401 const TargetData &TD = *AP.TM.getTargetData();
1402 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
1403 TD.getTypeStoreSize(CFP->getType()), AddrSpace);
1407 assert(CFP->getType()->isPPC_FP128Ty() &&
1408 "Floating point constant type not handled");
1409 // All long double variants are printed as hex
1410 // API needed to prevent premature destruction.
1411 APInt API = CFP->getValueAPF().bitcastToAPInt();
1412 const uint64_t *p = API.getRawData();
1413 if (AP.TM.getTargetData()->isBigEndian()) {
1414 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1415 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1417 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1418 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1422 static void EmitGlobalConstantLargeInt(const ConstantInt *CI,
1423 unsigned AddrSpace, AsmPrinter &AP) {
1424 const TargetData *TD = AP.TM.getTargetData();
1425 unsigned BitWidth = CI->getBitWidth();
1426 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
1428 // We don't expect assemblers to support integer data directives
1429 // for more than 64 bits, so we emit the data in at most 64-bit
1430 // quantities at a time.
1431 const uint64_t *RawData = CI->getValue().getRawData();
1432 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1433 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1434 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1438 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1439 void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1440 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) {
1441 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1442 if (Size == 0) Size = 1; // An empty "_foo:" followed by a section is undef.
1443 return OutStreamer.EmitZeros(Size, AddrSpace);
1446 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1447 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1454 OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue());
1455 OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1458 EmitGlobalConstantLargeInt(CI, AddrSpace, *this);
1463 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1464 return EmitGlobalConstantArray(CVA, AddrSpace, *this);
1466 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1467 return EmitGlobalConstantStruct(CVS, AddrSpace, *this);
1469 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1470 return EmitGlobalConstantFP(CFP, AddrSpace, *this);
1472 if (isa<ConstantPointerNull>(CV)) {
1473 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1474 OutStreamer.EmitIntValue(0, Size, AddrSpace);
1478 if (const ConstantUnion *CVU = dyn_cast<ConstantUnion>(CV))
1479 return EmitGlobalConstantUnion(CVU, AddrSpace, *this);
1481 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1482 return EmitGlobalConstantVector(V, AddrSpace, *this);
1484 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1485 // thread the streamer with EmitValue.
1486 OutStreamer.EmitValue(LowerConstant(CV, *this),
1487 TM.getTargetData()->getTypeAllocSize(CV->getType()),
1491 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1492 // Target doesn't support this yet!
1493 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1496 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1498 OS << '+' << Offset;
1499 else if (Offset < 0)
1503 //===----------------------------------------------------------------------===//
1504 // Symbol Lowering Routines.
1505 //===----------------------------------------------------------------------===//
1507 /// GetTempSymbol - Return the MCSymbol corresponding to the assembler
1508 /// temporary label with the specified stem and unique ID.
1509 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const {
1510 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) +
1514 /// GetTempSymbol - Return an assembler temporary label with the specified
1516 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const {
1517 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix())+
1522 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
1523 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
1526 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
1527 return MMI->getAddrLabelSymbol(BB);
1530 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1531 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1532 return OutContext.GetOrCreateSymbol
1533 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
1534 + "_" + Twine(CPID));
1537 /// GetJTISymbol - Return the symbol for the specified jump table entry.
1538 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1539 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
1542 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
1543 /// FIXME: privatize to AsmPrinter.
1544 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
1545 return OutContext.GetOrCreateSymbol
1546 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
1547 Twine(UID) + "_set_" + Twine(MBBID));
1550 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1551 /// global value name as its base, with the specified suffix, and where the
1552 /// symbol is forced to have private linkage if ForcePrivate is true.
1553 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1555 bool ForcePrivate) const {
1556 SmallString<60> NameStr;
1557 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1558 NameStr.append(Suffix.begin(), Suffix.end());
1559 return OutContext.GetOrCreateSymbol(NameStr.str());
1562 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
1564 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
1565 SmallString<60> NameStr;
1566 Mang->getNameWithPrefix(NameStr, Sym);
1567 return OutContext.GetOrCreateSymbol(NameStr.str());
1572 /// PrintParentLoopComment - Print comments about parent loops of this one.
1573 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1574 unsigned FunctionNumber) {
1575 if (Loop == 0) return;
1576 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
1577 OS.indent(Loop->getLoopDepth()*2)
1578 << "Parent Loop BB" << FunctionNumber << "_"
1579 << Loop->getHeader()->getNumber()
1580 << " Depth=" << Loop->getLoopDepth() << '\n';
1584 /// PrintChildLoopComment - Print comments about child loops within
1585 /// the loop for this basic block, with nesting.
1586 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1587 unsigned FunctionNumber) {
1588 // Add child loop information
1589 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
1590 OS.indent((*CL)->getLoopDepth()*2)
1591 << "Child Loop BB" << FunctionNumber << "_"
1592 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
1594 PrintChildLoopComment(OS, *CL, FunctionNumber);
1598 /// EmitBasicBlockLoopComments - Pretty-print comments for basic blocks.
1599 static void EmitBasicBlockLoopComments(const MachineBasicBlock &MBB,
1600 const MachineLoopInfo *LI,
1601 const AsmPrinter &AP) {
1602 // Add loop depth information
1603 const MachineLoop *Loop = LI->getLoopFor(&MBB);
1604 if (Loop == 0) return;
1606 MachineBasicBlock *Header = Loop->getHeader();
1607 assert(Header && "No header for loop");
1609 // If this block is not a loop header, just print out what is the loop header
1611 if (Header != &MBB) {
1612 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
1613 Twine(AP.getFunctionNumber())+"_" +
1614 Twine(Loop->getHeader()->getNumber())+
1615 " Depth="+Twine(Loop->getLoopDepth()));
1619 // Otherwise, it is a loop header. Print out information about child and
1621 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
1623 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
1626 OS.indent(Loop->getLoopDepth()*2-2);
1631 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
1633 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
1637 /// EmitBasicBlockStart - This method prints the label for the specified
1638 /// MachineBasicBlock, an alignment (if present) and a comment describing
1639 /// it if appropriate.
1640 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
1641 // Emit an alignment directive for this block, if needed.
1642 if (unsigned Align = MBB->getAlignment())
1643 EmitAlignment(Log2_32(Align));
1645 // If the block has its address taken, emit any labels that were used to
1646 // reference the block. It is possible that there is more than one label
1647 // here, because multiple LLVM BB's may have been RAUW'd to this block after
1648 // the references were generated.
1649 if (MBB->hasAddressTaken()) {
1650 const BasicBlock *BB = MBB->getBasicBlock();
1652 OutStreamer.AddComment("Block address taken");
1654 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
1656 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
1657 OutStreamer.EmitLabel(Syms[i]);
1660 // Print the main label for the block.
1661 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
1662 if (isVerbose() && OutStreamer.hasRawTextSupport()) {
1663 if (const BasicBlock *BB = MBB->getBasicBlock())
1665 OutStreamer.AddComment("%" + BB->getName());
1667 EmitBasicBlockLoopComments(*MBB, LI, *this);
1669 // NOTE: Want this comment at start of line, don't emit with AddComment.
1670 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" +
1671 Twine(MBB->getNumber()) + ":");
1675 if (const BasicBlock *BB = MBB->getBasicBlock())
1677 OutStreamer.AddComment("%" + BB->getName());
1678 EmitBasicBlockLoopComments(*MBB, LI, *this);
1681 OutStreamer.EmitLabel(MBB->getSymbol());
1685 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility) const {
1686 MCSymbolAttr Attr = MCSA_Invalid;
1688 switch (Visibility) {
1690 case GlobalValue::HiddenVisibility:
1691 Attr = MAI->getHiddenVisibilityAttr();
1693 case GlobalValue::ProtectedVisibility:
1694 Attr = MAI->getProtectedVisibilityAttr();
1698 if (Attr != MCSA_Invalid)
1699 OutStreamer.EmitSymbolAttribute(Sym, Attr);
1702 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
1703 /// exactly one predecessor and the control transfer mechanism between
1704 /// the predecessor and this block is a fall-through.
1706 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
1707 // If this is a landing pad, it isn't a fall through. If it has no preds,
1708 // then nothing falls through to it.
1709 if (MBB->isLandingPad() || MBB->pred_empty())
1712 // If there isn't exactly one predecessor, it can't be a fall through.
1713 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
1715 if (PI2 != MBB->pred_end())
1718 // The predecessor has to be immediately before this block.
1719 const MachineBasicBlock *Pred = *PI;
1721 if (!Pred->isLayoutSuccessor(MBB))
1724 // If the block is completely empty, then it definitely does fall through.
1728 // Otherwise, check the last instruction.
1729 const MachineInstr &LastInst = Pred->back();
1730 return !LastInst.getDesc().isBarrier();
1735 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1736 if (!S->usesMetadata())
1739 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
1740 gcp_map_type::iterator GCPI = GCMap.find(S);
1741 if (GCPI != GCMap.end())
1742 return GCPI->second;
1744 const char *Name = S->getName().c_str();
1746 for (GCMetadataPrinterRegistry::iterator
1747 I = GCMetadataPrinterRegistry::begin(),
1748 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1749 if (strcmp(Name, I->getName()) == 0) {
1750 GCMetadataPrinter *GMP = I->instantiate();
1752 GCMap.insert(std::make_pair(S, GMP));
1756 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));