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()) {
286 if (Size == 0) Size = 1; // zerofill of 0 bytes is undefined.
289 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
290 // .zerofill __DATA, __common, _foo, 400, 5
291 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
295 OutStreamer.SwitchSection(TheSection);
297 EmitLinkage(GV->getLinkage(), GVSym);
298 EmitAlignment(AlignLog, GV);
301 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
302 /*PrintType=*/false, GV->getParent());
303 OutStreamer.GetCommentOS() << '\n';
305 OutStreamer.EmitLabel(GVSym);
307 EmitGlobalConstant(GV->getInitializer());
309 if (MAI->hasDotTypeDotSizeDirective())
311 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
313 OutStreamer.AddBlankLine();
316 /// EmitFunctionHeader - This method emits the header for the current
318 void AsmPrinter::EmitFunctionHeader() {
319 // Print out constants referenced by the function
322 // Print the 'header' of function.
323 const Function *F = MF->getFunction();
325 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
326 EmitVisibility(CurrentFnSym, F->getVisibility());
328 EmitLinkage(F->getLinkage(), CurrentFnSym);
329 EmitAlignment(MF->getAlignment(), F);
331 if (MAI->hasDotTypeDotSizeDirective())
332 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
335 WriteAsOperand(OutStreamer.GetCommentOS(), F,
336 /*PrintType=*/false, F->getParent());
337 OutStreamer.GetCommentOS() << '\n';
340 // Emit the CurrentFnSym. This is a virtual function to allow targets to
341 // do their wild and crazy things as required.
342 EmitFunctionEntryLabel();
344 // If the function had address-taken blocks that got deleted, then we have
345 // references to the dangling symbols. Emit them at the start of the function
346 // so that we don't get references to undefined symbols.
347 std::vector<MCSymbol*> DeadBlockSyms;
348 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
349 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
350 OutStreamer.AddComment("Address taken block that was later removed");
351 OutStreamer.EmitLabel(DeadBlockSyms[i]);
354 // Add some workaround for linkonce linkage on Cygwin\MinGW.
355 if (MAI->getLinkOnceDirective() != 0 &&
356 (F->hasLinkOnceLinkage() || F->hasWeakLinkage())) {
357 // FIXME: What is this?
359 OutContext.GetOrCreateSymbol(Twine("Lllvm$workaround$fake$stub$")+
360 CurrentFnSym->getName());
361 OutStreamer.EmitLabel(FakeStub);
364 // Emit pre-function debug and/or EH information.
366 if (TimePassesIsEnabled) {
367 NamedRegionTimer T(EHTimerName, DWARFGroupName);
368 DE->BeginFunction(MF);
370 DE->BeginFunction(MF);
374 if (TimePassesIsEnabled) {
375 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
376 DD->beginFunction(MF);
378 DD->beginFunction(MF);
383 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
384 /// function. This can be overridden by targets as required to do custom stuff.
385 void AsmPrinter::EmitFunctionEntryLabel() {
386 OutStreamer.EmitLabel(CurrentFnSym);
390 /// EmitComments - Pretty-print comments for instructions.
391 static void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
392 const MachineFunction *MF = MI.getParent()->getParent();
393 const TargetMachine &TM = MF->getTarget();
395 DebugLoc DL = MI.getDebugLoc();
396 if (!DL.isUnknown()) { // Print source line info.
397 DIScope Scope(DL.getScope(MF->getFunction()->getContext()));
398 // Omit the directory, because it's likely to be long and uninteresting.
400 CommentOS << Scope.getFilename();
402 CommentOS << "<unknown>";
403 CommentOS << ':' << DL.getLine();
404 if (DL.getCol() != 0)
405 CommentOS << ':' << DL.getCol();
409 // Check for spills and reloads
412 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
414 // We assume a single instruction only has a spill or reload, not
416 const MachineMemOperand *MMO;
417 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
418 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
419 MMO = *MI.memoperands_begin();
420 CommentOS << MMO->getSize() << "-byte Reload\n";
422 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
423 if (FrameInfo->isSpillSlotObjectIndex(FI))
424 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
425 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
426 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
427 MMO = *MI.memoperands_begin();
428 CommentOS << MMO->getSize() << "-byte Spill\n";
430 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
431 if (FrameInfo->isSpillSlotObjectIndex(FI))
432 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
435 // Check for spill-induced copies
436 unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
437 if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg,
438 SrcSubIdx, DstSubIdx)) {
439 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
440 CommentOS << " Reload Reuse\n";
444 /// EmitImplicitDef - This method emits the specified machine instruction
445 /// that is an implicit def.
446 static void EmitImplicitDef(const MachineInstr *MI, AsmPrinter &AP) {
447 unsigned RegNo = MI->getOperand(0).getReg();
448 AP.OutStreamer.AddComment(Twine("implicit-def: ") +
449 AP.TM.getRegisterInfo()->getName(RegNo));
450 AP.OutStreamer.AddBlankLine();
453 static void EmitKill(const MachineInstr *MI, AsmPrinter &AP) {
454 std::string Str = "kill:";
455 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
456 const MachineOperand &Op = MI->getOperand(i);
457 assert(Op.isReg() && "KILL instruction must have only register operands");
459 Str += AP.TM.getRegisterInfo()->getName(Op.getReg());
460 Str += (Op.isDef() ? "<def>" : "<kill>");
462 AP.OutStreamer.AddComment(Str);
463 AP.OutStreamer.AddBlankLine();
466 /// EmitDebugValueComment - This method handles the target-independent form
467 /// of DBG_VALUE, returning true if it was able to do so. A false return
468 /// means the target will need to handle MI in EmitInstruction.
469 static bool EmitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
470 // This code handles only the 3-operand target-independent form.
471 if (MI->getNumOperands() != 3)
474 SmallString<128> Str;
475 raw_svector_ostream OS(Str);
476 OS << '\t' << AP.MAI->getCommentString() << "DEBUG_VALUE: ";
478 // cast away const; DIetc do not take const operands for some reason.
479 DIVariable V(const_cast<MDNode*>(MI->getOperand(2).getMetadata()));
480 OS << V.getName() << " <- ";
482 // Register or immediate value. Register 0 means undef.
483 if (MI->getOperand(0).isFPImm()) {
484 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
485 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
486 OS << (double)APF.convertToFloat();
487 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
488 OS << APF.convertToDouble();
490 // There is no good way to print long double. Convert a copy to
491 // double. Ah well, it's only a comment.
493 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
495 OS << "(long double) " << APF.convertToDouble();
497 } else if (MI->getOperand(0).isImm()) {
498 OS << MI->getOperand(0).getImm();
500 assert(MI->getOperand(0).isReg() && "Unknown operand type");
501 if (MI->getOperand(0).getReg() == 0) {
502 // Suppress offset, it is not meaningful here.
504 // NOTE: Want this comment at start of line, don't emit with AddComment.
505 AP.OutStreamer.EmitRawText(OS.str());
508 OS << AP.TM.getRegisterInfo()->getName(MI->getOperand(0).getReg());
511 OS << '+' << MI->getOperand(1).getImm();
512 // NOTE: Want this comment at start of line, don't emit with AddComment.
513 AP.OutStreamer.EmitRawText(OS.str());
517 /// EmitFunctionBody - This method emits the body and trailer for a
519 void AsmPrinter::EmitFunctionBody() {
520 // Emit target-specific gunk before the function body.
521 EmitFunctionBodyStart();
523 bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo();
525 // Print out code for the function.
526 bool HasAnyRealCode = false;
527 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
529 // Print a label for the basic block.
530 EmitBasicBlockStart(I);
531 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
533 // Print the assembly for the instruction.
534 if (!II->isLabel() && !II->isImplicitDef() && !II->isKill()) {
535 HasAnyRealCode = true;
539 if (ShouldPrintDebugScopes) {
540 if (TimePassesIsEnabled) {
541 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
549 EmitComments(*II, OutStreamer.GetCommentOS());
551 switch (II->getOpcode()) {
552 case TargetOpcode::DBG_LABEL:
553 case TargetOpcode::EH_LABEL:
554 case TargetOpcode::GC_LABEL:
555 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol());
557 case TargetOpcode::INLINEASM:
560 case TargetOpcode::DBG_VALUE:
562 if (!EmitDebugValueComment(II, *this))
566 case TargetOpcode::IMPLICIT_DEF:
567 if (isVerbose()) EmitImplicitDef(II, *this);
569 case TargetOpcode::KILL:
570 if (isVerbose()) EmitKill(II, *this);
577 if (ShouldPrintDebugScopes) {
578 if (TimePassesIsEnabled) {
579 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
588 // If the function is empty and the object file uses .subsections_via_symbols,
589 // then we need to emit *something* to the function body to prevent the
590 // labels from collapsing together. Just emit a noop.
591 if (MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) {
593 TM.getInstrInfo()->getNoopForMachoTarget(Noop);
594 if (Noop.getOpcode()) {
595 OutStreamer.AddComment("avoids zero-length function");
596 OutStreamer.EmitInstruction(Noop);
597 } else // Target not mc-ized yet.
598 OutStreamer.EmitRawText(StringRef("\tnop\n"));
601 // Emit target-specific gunk after the function body.
602 EmitFunctionBodyEnd();
604 // If the target wants a .size directive for the size of the function, emit
606 if (MAI->hasDotTypeDotSizeDirective()) {
607 // Create a symbol for the end of function, so we can get the size as
608 // difference between the function label and the temp label.
609 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
610 OutStreamer.EmitLabel(FnEndLabel);
612 const MCExpr *SizeExp =
613 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
614 MCSymbolRefExpr::Create(CurrentFnSym, OutContext),
616 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
619 // Emit post-function debug information.
621 if (TimePassesIsEnabled) {
622 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
629 if (TimePassesIsEnabled) {
630 NamedRegionTimer T(EHTimerName, DWARFGroupName);
638 // Print out jump tables referenced by the function.
641 OutStreamer.AddBlankLine();
644 /// getDebugValueLocation - Get location information encoded by DBG_VALUE
646 MachineLocation AsmPrinter::getDebugValueLocation(const MachineInstr *MI) const {
647 // Target specific DBG_VALUE instructions are handled by each target.
648 return MachineLocation();
651 bool AsmPrinter::doFinalization(Module &M) {
652 // Emit global variables.
653 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
655 EmitGlobalVariable(I);
657 // Finalize debug and EH information.
659 if (TimePassesIsEnabled) {
660 NamedRegionTimer T(EHTimerName, DWARFGroupName);
668 if (TimePassesIsEnabled) {
669 NamedRegionTimer T(DbgTimerName, DWARFGroupName);
677 // If the target wants to know about weak references, print them all.
678 if (MAI->getWeakRefDirective()) {
679 // FIXME: This is not lazy, it would be nice to only print weak references
680 // to stuff that is actually used. Note that doing so would require targets
681 // to notice uses in operands (due to constant exprs etc). This should
682 // happen with the MC stuff eventually.
684 // Print out module-level global variables here.
685 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
687 if (!I->hasExternalWeakLinkage()) continue;
688 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
691 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
692 if (!I->hasExternalWeakLinkage()) continue;
693 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
697 if (MAI->hasSetDirective()) {
698 OutStreamer.AddBlankLine();
699 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
701 MCSymbol *Name = Mang->getSymbol(I);
703 const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
704 MCSymbol *Target = Mang->getSymbol(GV);
706 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
707 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
708 else if (I->hasWeakLinkage())
709 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
711 assert(I->hasLocalLinkage() && "Invalid alias linkage");
713 EmitVisibility(Name, I->getVisibility());
715 // Emit the directives as assignments aka .set:
716 OutStreamer.EmitAssignment(Name,
717 MCSymbolRefExpr::Create(Target, OutContext));
721 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
722 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
723 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
724 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
725 MP->finishAssembly(*this);
727 // If we don't have any trampolines, then we don't require stack memory
728 // to be executable. Some targets have a directive to declare this.
729 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
730 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
731 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext))
732 OutStreamer.SwitchSection(S);
734 // Allow the target to emit any magic that it wants at the end of the file,
735 // after everything else has gone out.
738 delete Mang; Mang = 0;
741 OutStreamer.Finish();
745 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
747 // Get the function symbol.
748 CurrentFnSym = Mang->getSymbol(MF.getFunction());
751 LI = &getAnalysis<MachineLoopInfo>();
755 // SectionCPs - Keep track the alignment, constpool entries per Section.
759 SmallVector<unsigned, 4> CPEs;
760 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
764 /// EmitConstantPool - Print to the current output stream assembly
765 /// representations of the constants in the constant pool MCP. This is
766 /// used to print out constants which have been "spilled to memory" by
767 /// the code generator.
769 void AsmPrinter::EmitConstantPool() {
770 const MachineConstantPool *MCP = MF->getConstantPool();
771 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
772 if (CP.empty()) return;
774 // Calculate sections for constant pool entries. We collect entries to go into
775 // the same section together to reduce amount of section switch statements.
776 SmallVector<SectionCPs, 4> CPSections;
777 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
778 const MachineConstantPoolEntry &CPE = CP[i];
779 unsigned Align = CPE.getAlignment();
782 switch (CPE.getRelocationInfo()) {
783 default: llvm_unreachable("Unknown section kind");
784 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
786 Kind = SectionKind::getReadOnlyWithRelLocal();
789 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
790 case 4: Kind = SectionKind::getMergeableConst4(); break;
791 case 8: Kind = SectionKind::getMergeableConst8(); break;
792 case 16: Kind = SectionKind::getMergeableConst16();break;
793 default: Kind = SectionKind::getMergeableConst(); break;
797 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
799 // The number of sections are small, just do a linear search from the
800 // last section to the first.
802 unsigned SecIdx = CPSections.size();
803 while (SecIdx != 0) {
804 if (CPSections[--SecIdx].S == S) {
810 SecIdx = CPSections.size();
811 CPSections.push_back(SectionCPs(S, Align));
814 if (Align > CPSections[SecIdx].Alignment)
815 CPSections[SecIdx].Alignment = Align;
816 CPSections[SecIdx].CPEs.push_back(i);
819 // Now print stuff into the calculated sections.
820 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
821 OutStreamer.SwitchSection(CPSections[i].S);
822 EmitAlignment(Log2_32(CPSections[i].Alignment));
825 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
826 unsigned CPI = CPSections[i].CPEs[j];
827 MachineConstantPoolEntry CPE = CP[CPI];
829 // Emit inter-object padding for alignment.
830 unsigned AlignMask = CPE.getAlignment() - 1;
831 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
832 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/);
834 const Type *Ty = CPE.getType();
835 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
837 // Emit the label with a comment on it.
839 OutStreamer.GetCommentOS() << "constant pool ";
840 WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(),
841 MF->getFunction()->getParent());
842 OutStreamer.GetCommentOS() << '\n';
844 OutStreamer.EmitLabel(GetCPISymbol(CPI));
846 if (CPE.isMachineConstantPoolEntry())
847 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
849 EmitGlobalConstant(CPE.Val.ConstVal);
854 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
855 /// by the current function to the current output stream.
857 void AsmPrinter::EmitJumpTableInfo() {
858 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
859 if (MJTI == 0) return;
860 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
861 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
862 if (JT.empty()) return;
864 // Pick the directive to use to print the jump table entries, and switch to
865 // the appropriate section.
866 const Function *F = MF->getFunction();
867 bool JTInDiffSection = false;
868 if (// In PIC mode, we need to emit the jump table to the same section as the
869 // function body itself, otherwise the label differences won't make sense.
870 // FIXME: Need a better predicate for this: what about custom entries?
871 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
872 // We should also do if the section name is NULL or function is declared
873 // in discardable section
874 // FIXME: this isn't the right predicate, should be based on the MCSection
876 F->isWeakForLinker()) {
877 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
879 // Otherwise, drop it in the readonly section.
880 const MCSection *ReadOnlySection =
881 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
882 OutStreamer.SwitchSection(ReadOnlySection);
883 JTInDiffSection = true;
886 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData())));
888 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
889 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
891 // If this jump table was deleted, ignore it.
892 if (JTBBs.empty()) continue;
894 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
895 // .set directive for each unique entry. This reduces the number of
896 // relocations the assembler will generate for the jump table.
897 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
898 MAI->hasSetDirective()) {
899 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
900 const TargetLowering *TLI = TM.getTargetLowering();
901 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
902 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
903 const MachineBasicBlock *MBB = JTBBs[ii];
904 if (!EmittedSets.insert(MBB)) continue;
906 // .set LJTSet, LBB32-base
908 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
909 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
910 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
914 // On some targets (e.g. Darwin) we want to emit two consequtive labels
915 // before each jump table. The first label is never referenced, but tells
916 // the assembler and linker the extents of the jump table object. The
917 // second label is actually referenced by the code.
918 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
919 // FIXME: This doesn't have to have any specific name, just any randomly
920 // named and numbered 'l' label would work. Simplify GetJTISymbol.
921 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
923 OutStreamer.EmitLabel(GetJTISymbol(JTI));
925 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
926 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
930 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
932 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
933 const MachineBasicBlock *MBB,
934 unsigned UID) const {
935 const MCExpr *Value = 0;
936 switch (MJTI->getEntryKind()) {
937 case MachineJumpTableInfo::EK_Inline:
938 llvm_unreachable("Cannot emit EK_Inline jump table entry"); break;
939 case MachineJumpTableInfo::EK_Custom32:
940 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
943 case MachineJumpTableInfo::EK_BlockAddress:
944 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
946 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
948 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
949 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
950 // with a relocation as gp-relative, e.g.:
952 MCSymbol *MBBSym = MBB->getSymbol();
953 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
957 case MachineJumpTableInfo::EK_LabelDifference32: {
958 // EK_LabelDifference32 - Each entry is the address of the block minus
959 // the address of the jump table. This is used for PIC jump tables where
960 // gprel32 is not supported. e.g.:
961 // .word LBB123 - LJTI1_2
962 // If the .set directive is supported, this is emitted as:
963 // .set L4_5_set_123, LBB123 - LJTI1_2
964 // .word L4_5_set_123
966 // If we have emitted set directives for the jump table entries, print
967 // them rather than the entries themselves. If we're emitting PIC, then
968 // emit the table entries as differences between two text section labels.
969 if (MAI->hasSetDirective()) {
970 // If we used .set, reference the .set's symbol.
971 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
975 // Otherwise, use the difference as the jump table entry.
976 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
977 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
978 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
983 assert(Value && "Unknown entry kind!");
985 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData());
986 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0);
990 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
991 /// special global used by LLVM. If so, emit it and return true, otherwise
992 /// do nothing and return false.
993 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
994 if (GV->getName() == "llvm.used") {
995 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
996 EmitLLVMUsedList(GV->getInitializer());
1000 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
1001 if (GV->getSection() == "llvm.metadata" ||
1002 GV->hasAvailableExternallyLinkage())
1005 if (!GV->hasAppendingLinkage()) return false;
1007 assert(GV->hasInitializer() && "Not a special LLVM global!");
1009 const TargetData *TD = TM.getTargetData();
1010 unsigned Align = Log2_32(TD->getPointerPrefAlignment());
1011 if (GV->getName() == "llvm.global_ctors") {
1012 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection());
1013 EmitAlignment(Align, 0);
1014 EmitXXStructorList(GV->getInitializer());
1016 if (TM.getRelocationModel() == Reloc::Static &&
1017 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1018 StringRef Sym(".constructors_used");
1019 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1025 if (GV->getName() == "llvm.global_dtors") {
1026 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection());
1027 EmitAlignment(Align, 0);
1028 EmitXXStructorList(GV->getInitializer());
1030 if (TM.getRelocationModel() == Reloc::Static &&
1031 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1032 StringRef Sym(".destructors_used");
1033 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1042 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1043 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1044 /// is true, as being used with this directive.
1045 void AsmPrinter::EmitLLVMUsedList(Constant *List) {
1046 // Should be an array of 'i8*'.
1047 ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1048 if (InitList == 0) return;
1050 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1051 const GlobalValue *GV =
1052 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1053 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
1054 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip);
1058 /// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the
1059 /// function pointers, ignoring the init priority.
1060 void AsmPrinter::EmitXXStructorList(Constant *List) {
1061 // Should be an array of '{ int, void ()* }' structs. The first value is the
1062 // init priority, which we ignore.
1063 if (!isa<ConstantArray>(List)) return;
1064 ConstantArray *InitList = cast<ConstantArray>(List);
1065 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
1066 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
1067 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs.
1069 if (CS->getOperand(1)->isNullValue())
1070 return; // Found a null terminator, exit printing.
1071 // Emit the function pointer.
1072 EmitGlobalConstant(CS->getOperand(1));
1076 //===--------------------------------------------------------------------===//
1077 // Emission and print routines
1080 /// EmitInt8 - Emit a byte directive and value.
1082 void AsmPrinter::EmitInt8(int Value) const {
1083 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/);
1086 /// EmitInt16 - Emit a short directive and value.
1088 void AsmPrinter::EmitInt16(int Value) const {
1089 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/);
1092 /// EmitInt32 - Emit a long directive and value.
1094 void AsmPrinter::EmitInt32(int Value) const {
1095 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/);
1098 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
1099 /// in bytes of the directive is specified by Size and Hi/Lo specify the
1100 /// labels. This implicitly uses .set if it is available.
1101 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1102 unsigned Size) const {
1103 // Get the Hi-Lo expression.
1104 const MCExpr *Diff =
1105 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1106 MCSymbolRefExpr::Create(Lo, OutContext),
1109 if (!MAI->hasSetDirective()) {
1110 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/);
1114 // Otherwise, emit with .set (aka assignment).
1115 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1116 OutStreamer.EmitAssignment(SetLabel, Diff);
1117 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/);
1120 /// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo"
1121 /// where the size in bytes of the directive is specified by Size and Hi/Lo
1122 /// specify the labels. This implicitly uses .set if it is available.
1123 void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset,
1124 const MCSymbol *Lo, unsigned Size)
1127 // Emit Hi+Offset - Lo
1128 // Get the Hi+Offset expression.
1129 const MCExpr *Plus =
1130 MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext),
1131 MCConstantExpr::Create(Offset, OutContext),
1134 // Get the Hi+Offset-Lo expression.
1135 const MCExpr *Diff =
1136 MCBinaryExpr::CreateSub(Plus,
1137 MCSymbolRefExpr::Create(Lo, OutContext),
1140 if (!MAI->hasSetDirective())
1141 OutStreamer.EmitValue(Diff, 4, 0/*AddrSpace*/);
1143 // Otherwise, emit with .set (aka assignment).
1144 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1145 OutStreamer.EmitAssignment(SetLabel, Diff);
1146 OutStreamer.EmitSymbolValue(SetLabel, 4, 0/*AddrSpace*/);
1151 //===----------------------------------------------------------------------===//
1153 // EmitAlignment - Emit an alignment directive to the specified power of
1154 // two boundary. For example, if you pass in 3 here, you will get an 8
1155 // byte alignment. If a global value is specified, and if that global has
1156 // an explicit alignment requested, it will unconditionally override the
1157 // alignment request. However, if ForcedAlignBits is specified, this value
1158 // has final say: the ultimate alignment will be the max of ForcedAlignBits
1159 // and the alignment computed with NumBits and the global.
1161 // The algorithm is:
1163 // if (GV && GV->hasalignment) Align = GV->getAlignment();
1165 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV) const {
1166 if (GV && GV->getAlignment())
1167 NumBits = Log2_32(GV->getAlignment());
1169 if (NumBits == 0) return; // No need to emit alignment.
1171 if (getCurrentSection()->getKind().isText())
1172 OutStreamer.EmitCodeAlignment(1 << NumBits);
1174 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
1177 //===----------------------------------------------------------------------===//
1178 // Constant emission.
1179 //===----------------------------------------------------------------------===//
1181 /// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
1183 static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) {
1184 MCContext &Ctx = AP.OutContext;
1186 if (CV->isNullValue() || isa<UndefValue>(CV))
1187 return MCConstantExpr::Create(0, Ctx);
1189 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1190 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1192 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1193 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx);
1194 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1195 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1197 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1199 llvm_unreachable("Unknown constant value to lower!");
1200 return MCConstantExpr::Create(0, Ctx);
1203 switch (CE->getOpcode()) {
1205 // If the code isn't optimized, there may be outstanding folding
1206 // opportunities. Attempt to fold the expression using TargetData as a
1207 // last resort before giving up.
1209 ConstantFoldConstantExpression(CE, AP.TM.getTargetData()))
1211 return LowerConstant(C, AP);
1215 llvm_unreachable("FIXME: Don't support this constant expr");
1216 case Instruction::GetElementPtr: {
1217 const TargetData &TD = *AP.TM.getTargetData();
1218 // Generate a symbolic expression for the byte address
1219 const Constant *PtrVal = CE->getOperand(0);
1220 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
1221 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0],
1224 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
1228 // Truncate/sext the offset to the pointer size.
1229 if (TD.getPointerSizeInBits() != 64) {
1230 int SExtAmount = 64-TD.getPointerSizeInBits();
1231 Offset = (Offset << SExtAmount) >> SExtAmount;
1234 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1238 case Instruction::Trunc:
1239 // We emit the value and depend on the assembler to truncate the generated
1240 // expression properly. This is important for differences between
1241 // blockaddress labels. Since the two labels are in the same function, it
1242 // is reasonable to treat their delta as a 32-bit value.
1244 case Instruction::BitCast:
1245 return LowerConstant(CE->getOperand(0), AP);
1247 case Instruction::IntToPtr: {
1248 const TargetData &TD = *AP.TM.getTargetData();
1249 // Handle casts to pointers by changing them into casts to the appropriate
1250 // integer type. This promotes constant folding and simplifies this code.
1251 Constant *Op = CE->getOperand(0);
1252 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
1254 return LowerConstant(Op, AP);
1257 case Instruction::PtrToInt: {
1258 const TargetData &TD = *AP.TM.getTargetData();
1259 // Support only foldable casts to/from pointers that can be eliminated by
1260 // changing the pointer to the appropriately sized integer type.
1261 Constant *Op = CE->getOperand(0);
1262 const Type *Ty = CE->getType();
1264 const MCExpr *OpExpr = LowerConstant(Op, AP);
1266 // We can emit the pointer value into this slot if the slot is an
1267 // integer slot equal to the size of the pointer.
1268 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
1271 // Otherwise the pointer is smaller than the resultant integer, mask off
1272 // the high bits so we are sure to get a proper truncation if the input is
1274 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
1275 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1276 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1279 // The MC library also has a right-shift operator, but it isn't consistently
1280 // signed or unsigned between different targets.
1281 case Instruction::Add:
1282 case Instruction::Sub:
1283 case Instruction::Mul:
1284 case Instruction::SDiv:
1285 case Instruction::SRem:
1286 case Instruction::Shl:
1287 case Instruction::And:
1288 case Instruction::Or:
1289 case Instruction::Xor: {
1290 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP);
1291 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP);
1292 switch (CE->getOpcode()) {
1293 default: llvm_unreachable("Unknown binary operator constant cast expr");
1294 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1295 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1296 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1297 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1298 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1299 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1300 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1301 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1302 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1308 static void EmitGlobalConstantImpl(const Constant *C, unsigned AddrSpace,
1311 static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
1313 if (AddrSpace != 0 || !CA->isString()) {
1314 // Not a string. Print the values in successive locations
1315 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1316 EmitGlobalConstantImpl(CA->getOperand(i), AddrSpace, AP);
1320 // Otherwise, it can be emitted as .ascii.
1321 SmallVector<char, 128> TmpVec;
1322 TmpVec.reserve(CA->getNumOperands());
1323 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1324 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
1326 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace);
1329 static void EmitGlobalConstantVector(const ConstantVector *CV,
1330 unsigned AddrSpace, AsmPrinter &AP) {
1331 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1332 EmitGlobalConstantImpl(CV->getOperand(i), AddrSpace, AP);
1335 static void EmitGlobalConstantStruct(const ConstantStruct *CS,
1336 unsigned AddrSpace, AsmPrinter &AP) {
1337 // Print the fields in successive locations. Pad to align if needed!
1338 const TargetData *TD = AP.TM.getTargetData();
1339 unsigned Size = TD->getTypeAllocSize(CS->getType());
1340 const StructLayout *Layout = TD->getStructLayout(CS->getType());
1341 uint64_t SizeSoFar = 0;
1342 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1343 const Constant *Field = CS->getOperand(i);
1345 // Check if padding is needed and insert one or more 0s.
1346 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
1347 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1348 - Layout->getElementOffset(i)) - FieldSize;
1349 SizeSoFar += FieldSize + PadSize;
1351 // Now print the actual field value.
1352 EmitGlobalConstantImpl(Field, AddrSpace, AP);
1354 // Insert padding - this may include padding to increase the size of the
1355 // current field up to the ABI size (if the struct is not packed) as well
1356 // as padding to ensure that the next field starts at the right offset.
1357 AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
1359 assert(SizeSoFar == Layout->getSizeInBytes() &&
1360 "Layout of constant struct may be incorrect!");
1363 static void EmitGlobalConstantUnion(const ConstantUnion *CU,
1364 unsigned AddrSpace, AsmPrinter &AP) {
1365 const TargetData *TD = AP.TM.getTargetData();
1366 unsigned Size = TD->getTypeAllocSize(CU->getType());
1368 const Constant *Contents = CU->getOperand(0);
1369 unsigned FilledSize = TD->getTypeAllocSize(Contents->getType());
1371 // Print the actually filled part
1372 EmitGlobalConstantImpl(Contents, AddrSpace, AP);
1374 // And pad with enough zeroes
1375 AP.OutStreamer.EmitZeros(Size-FilledSize, AddrSpace);
1378 static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
1380 // FP Constants are printed as integer constants to avoid losing
1382 if (CFP->getType()->isDoubleTy()) {
1383 if (AP.isVerbose()) {
1384 double Val = CFP->getValueAPF().convertToDouble();
1385 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n';
1388 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1389 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1393 if (CFP->getType()->isFloatTy()) {
1394 if (AP.isVerbose()) {
1395 float Val = CFP->getValueAPF().convertToFloat();
1396 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n';
1398 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1399 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace);
1403 if (CFP->getType()->isX86_FP80Ty()) {
1404 // all long double variants are printed as hex
1405 // API needed to prevent premature destruction
1406 APInt API = CFP->getValueAPF().bitcastToAPInt();
1407 const uint64_t *p = API.getRawData();
1408 if (AP.isVerbose()) {
1409 // Convert to double so we can print the approximate val as a comment.
1410 APFloat DoubleVal = CFP->getValueAPF();
1412 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1414 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= "
1415 << DoubleVal.convertToDouble() << '\n';
1418 if (AP.TM.getTargetData()->isBigEndian()) {
1419 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1420 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1422 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1423 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1426 // Emit the tail padding for the long double.
1427 const TargetData &TD = *AP.TM.getTargetData();
1428 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
1429 TD.getTypeStoreSize(CFP->getType()), AddrSpace);
1433 assert(CFP->getType()->isPPC_FP128Ty() &&
1434 "Floating point constant type not handled");
1435 // All long double variants are printed as hex
1436 // API needed to prevent premature destruction.
1437 APInt API = CFP->getValueAPF().bitcastToAPInt();
1438 const uint64_t *p = API.getRawData();
1439 if (AP.TM.getTargetData()->isBigEndian()) {
1440 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1441 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1443 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1444 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1448 static void EmitGlobalConstantLargeInt(const ConstantInt *CI,
1449 unsigned AddrSpace, AsmPrinter &AP) {
1450 const TargetData *TD = AP.TM.getTargetData();
1451 unsigned BitWidth = CI->getBitWidth();
1452 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
1454 // We don't expect assemblers to support integer data directives
1455 // for more than 64 bits, so we emit the data in at most 64-bit
1456 // quantities at a time.
1457 const uint64_t *RawData = CI->getValue().getRawData();
1458 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1459 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1460 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1464 static void EmitGlobalConstantImpl(const Constant *CV, unsigned AddrSpace,
1466 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) {
1467 uint64_t Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType());
1468 return AP.OutStreamer.EmitZeros(Size, AddrSpace);
1471 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1472 unsigned Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType());
1479 AP.OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue());
1480 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1483 EmitGlobalConstantLargeInt(CI, AddrSpace, AP);
1488 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1489 return EmitGlobalConstantArray(CVA, AddrSpace, AP);
1491 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1492 return EmitGlobalConstantStruct(CVS, AddrSpace, AP);
1494 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1495 return EmitGlobalConstantFP(CFP, AddrSpace, AP);
1497 if (isa<ConstantPointerNull>(CV)) {
1498 unsigned Size = AP.TM.getTargetData()->getTypeAllocSize(CV->getType());
1499 AP.OutStreamer.EmitIntValue(0, Size, AddrSpace);
1503 if (const ConstantUnion *CVU = dyn_cast<ConstantUnion>(CV))
1504 return EmitGlobalConstantUnion(CVU, AddrSpace, AP);
1506 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1507 return EmitGlobalConstantVector(V, AddrSpace, AP);
1509 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1510 // thread the streamer with EmitValue.
1511 AP.OutStreamer.EmitValue(LowerConstant(CV, AP),
1512 AP.TM.getTargetData()->getTypeAllocSize(CV->getType()),
1516 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1517 void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1518 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1520 EmitGlobalConstantImpl(CV, AddrSpace, *this);
1521 else if (MAI->hasSubsectionsViaSymbols()) {
1522 // If the global has zero size, emit a single byte so that two labels don't
1523 // look like they are at the same location.
1524 OutStreamer.EmitIntValue(0, 1, AddrSpace);
1528 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1529 // Target doesn't support this yet!
1530 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1533 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1535 OS << '+' << Offset;
1536 else if (Offset < 0)
1540 //===----------------------------------------------------------------------===//
1541 // Symbol Lowering Routines.
1542 //===----------------------------------------------------------------------===//
1544 /// GetTempSymbol - Return the MCSymbol corresponding to the assembler
1545 /// temporary label with the specified stem and unique ID.
1546 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const {
1547 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) +
1551 /// GetTempSymbol - Return an assembler temporary label with the specified
1553 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const {
1554 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix())+
1559 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
1560 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
1563 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
1564 return MMI->getAddrLabelSymbol(BB);
1567 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1568 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1569 return OutContext.GetOrCreateSymbol
1570 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
1571 + "_" + Twine(CPID));
1574 /// GetJTISymbol - Return the symbol for the specified jump table entry.
1575 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1576 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
1579 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
1580 /// FIXME: privatize to AsmPrinter.
1581 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
1582 return OutContext.GetOrCreateSymbol
1583 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
1584 Twine(UID) + "_set_" + Twine(MBBID));
1587 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1588 /// global value name as its base, with the specified suffix, and where the
1589 /// symbol is forced to have private linkage if ForcePrivate is true.
1590 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1592 bool ForcePrivate) const {
1593 SmallString<60> NameStr;
1594 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1595 NameStr.append(Suffix.begin(), Suffix.end());
1596 return OutContext.GetOrCreateSymbol(NameStr.str());
1599 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
1601 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
1602 SmallString<60> NameStr;
1603 Mang->getNameWithPrefix(NameStr, Sym);
1604 return OutContext.GetOrCreateSymbol(NameStr.str());
1609 /// PrintParentLoopComment - Print comments about parent loops of this one.
1610 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1611 unsigned FunctionNumber) {
1612 if (Loop == 0) return;
1613 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
1614 OS.indent(Loop->getLoopDepth()*2)
1615 << "Parent Loop BB" << FunctionNumber << "_"
1616 << Loop->getHeader()->getNumber()
1617 << " Depth=" << Loop->getLoopDepth() << '\n';
1621 /// PrintChildLoopComment - Print comments about child loops within
1622 /// the loop for this basic block, with nesting.
1623 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1624 unsigned FunctionNumber) {
1625 // Add child loop information
1626 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
1627 OS.indent((*CL)->getLoopDepth()*2)
1628 << "Child Loop BB" << FunctionNumber << "_"
1629 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
1631 PrintChildLoopComment(OS, *CL, FunctionNumber);
1635 /// EmitBasicBlockLoopComments - Pretty-print comments for basic blocks.
1636 static void EmitBasicBlockLoopComments(const MachineBasicBlock &MBB,
1637 const MachineLoopInfo *LI,
1638 const AsmPrinter &AP) {
1639 // Add loop depth information
1640 const MachineLoop *Loop = LI->getLoopFor(&MBB);
1641 if (Loop == 0) return;
1643 MachineBasicBlock *Header = Loop->getHeader();
1644 assert(Header && "No header for loop");
1646 // If this block is not a loop header, just print out what is the loop header
1648 if (Header != &MBB) {
1649 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
1650 Twine(AP.getFunctionNumber())+"_" +
1651 Twine(Loop->getHeader()->getNumber())+
1652 " Depth="+Twine(Loop->getLoopDepth()));
1656 // Otherwise, it is a loop header. Print out information about child and
1658 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
1660 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
1663 OS.indent(Loop->getLoopDepth()*2-2);
1668 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
1670 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
1674 /// EmitBasicBlockStart - This method prints the label for the specified
1675 /// MachineBasicBlock, an alignment (if present) and a comment describing
1676 /// it if appropriate.
1677 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
1678 // Emit an alignment directive for this block, if needed.
1679 if (unsigned Align = MBB->getAlignment())
1680 EmitAlignment(Log2_32(Align));
1682 // If the block has its address taken, emit any labels that were used to
1683 // reference the block. It is possible that there is more than one label
1684 // here, because multiple LLVM BB's may have been RAUW'd to this block after
1685 // the references were generated.
1686 if (MBB->hasAddressTaken()) {
1687 const BasicBlock *BB = MBB->getBasicBlock();
1689 OutStreamer.AddComment("Block address taken");
1691 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
1693 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
1694 OutStreamer.EmitLabel(Syms[i]);
1697 // Print the main label for the block.
1698 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
1699 if (isVerbose() && OutStreamer.hasRawTextSupport()) {
1700 if (const BasicBlock *BB = MBB->getBasicBlock())
1702 OutStreamer.AddComment("%" + BB->getName());
1704 EmitBasicBlockLoopComments(*MBB, LI, *this);
1706 // NOTE: Want this comment at start of line, don't emit with AddComment.
1707 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" +
1708 Twine(MBB->getNumber()) + ":");
1712 if (const BasicBlock *BB = MBB->getBasicBlock())
1714 OutStreamer.AddComment("%" + BB->getName());
1715 EmitBasicBlockLoopComments(*MBB, LI, *this);
1718 OutStreamer.EmitLabel(MBB->getSymbol());
1722 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility) const {
1723 MCSymbolAttr Attr = MCSA_Invalid;
1725 switch (Visibility) {
1727 case GlobalValue::HiddenVisibility:
1728 Attr = MAI->getHiddenVisibilityAttr();
1730 case GlobalValue::ProtectedVisibility:
1731 Attr = MAI->getProtectedVisibilityAttr();
1735 if (Attr != MCSA_Invalid)
1736 OutStreamer.EmitSymbolAttribute(Sym, Attr);
1739 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
1740 /// exactly one predecessor and the control transfer mechanism between
1741 /// the predecessor and this block is a fall-through.
1743 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
1744 // If this is a landing pad, it isn't a fall through. If it has no preds,
1745 // then nothing falls through to it.
1746 if (MBB->isLandingPad() || MBB->pred_empty())
1749 // If there isn't exactly one predecessor, it can't be a fall through.
1750 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
1752 if (PI2 != MBB->pred_end())
1755 // The predecessor has to be immediately before this block.
1756 const MachineBasicBlock *Pred = *PI;
1758 if (!Pred->isLayoutSuccessor(MBB))
1761 // If the block is completely empty, then it definitely does fall through.
1765 // Otherwise, check the last instruction.
1766 const MachineInstr &LastInst = Pred->back();
1767 return !LastInst.getDesc().isBarrier();
1772 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1773 if (!S->usesMetadata())
1776 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
1777 gcp_map_type::iterator GCPI = GCMap.find(S);
1778 if (GCPI != GCMap.end())
1779 return GCPI->second;
1781 const char *Name = S->getName().c_str();
1783 for (GCMetadataPrinterRegistry::iterator
1784 I = GCMetadataPrinterRegistry::begin(),
1785 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1786 if (strcmp(Name, I->getName()) == 0) {
1787 GCMetadataPrinter *GMP = I->instantiate();
1789 GCMap.insert(std::make_pair(S, GMP));
1793 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));