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"
47 STATISTIC(EmittedInsts, "Number of machine instrs printed");
49 char AsmPrinter::ID = 0;
51 typedef DenseMap<GCStrategy*,GCMetadataPrinter*> gcp_map_type;
52 static gcp_map_type &getGCMap(void *&P) {
54 P = new gcp_map_type();
55 return *(gcp_map_type*)P;
59 AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
60 : MachineFunctionPass(&ID),
61 TM(tm), MAI(tm.getMCAsmInfo()),
62 OutContext(Streamer.getContext()),
63 OutStreamer(Streamer),
64 LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {
65 DD = 0; DE = 0; MMI = 0; LI = 0;
66 GCMetadataPrinters = 0;
67 VerboseAsm = Streamer.isVerboseAsm();
70 AsmPrinter::~AsmPrinter() {
71 assert(DD == 0 && DE == 0 && "Debug/EH info didn't get finalized");
73 if (GCMetadataPrinters != 0) {
74 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
76 for (gcp_map_type::iterator I = GCMap.begin(), E = GCMap.end(); I != E; ++I)
79 GCMetadataPrinters = 0;
85 /// getFunctionNumber - Return a unique ID for the current function.
87 unsigned AsmPrinter::getFunctionNumber() const {
88 return MF->getFunctionNumber();
91 TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
92 return TM.getTargetLowering()->getObjFileLowering();
96 /// getTargetData - Return information about data layout.
97 const TargetData &AsmPrinter::getTargetData() const {
98 return *TM.getTargetData();
101 /// getCurrentSection() - Return the current section we are emitting to.
102 const MCSection *AsmPrinter::getCurrentSection() const {
103 return OutStreamer.getCurrentSection();
108 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
109 AU.setPreservesAll();
110 MachineFunctionPass::getAnalysisUsage(AU);
111 AU.addRequired<MachineModuleInfo>();
112 AU.addRequired<GCModuleInfo>();
114 AU.addRequired<MachineLoopInfo>();
117 bool AsmPrinter::doInitialization(Module &M) {
118 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
119 MMI->AnalyzeModule(M);
121 // Initialize TargetLoweringObjectFile.
122 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
123 .Initialize(OutContext, TM);
125 Mang = new Mangler(OutContext, *TM.getTargetData());
127 // Allow the target to emit any magic that it wants at the start of the file.
128 EmitStartOfAsmFile(M);
130 // Very minimal debug info. It is ignored if we emit actual debug info. If we
131 // don't, this at least helps the user find where a global came from.
132 if (MAI->hasSingleParameterDotFile()) {
134 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
137 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
138 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
139 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
140 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
141 MP->beginAssembly(*this);
143 // Emit module-level inline asm if it exists.
144 if (!M.getModuleInlineAsm().empty()) {
145 OutStreamer.AddComment("Start of file scope inline assembly");
146 OutStreamer.AddBlankLine();
147 EmitInlineAsm(M.getModuleInlineAsm(), 0/*no loc cookie*/);
148 OutStreamer.AddComment("End of file scope inline assembly");
149 OutStreamer.AddBlankLine();
152 if (MAI->doesSupportDebugInformation())
153 DD = new DwarfDebug(this, &M);
155 if (MAI->doesSupportExceptionHandling())
156 DE = new DwarfException(this);
161 void AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const {
162 switch ((GlobalValue::LinkageTypes)Linkage) {
163 case GlobalValue::CommonLinkage:
164 case GlobalValue::LinkOnceAnyLinkage:
165 case GlobalValue::LinkOnceODRLinkage:
166 case GlobalValue::WeakAnyLinkage:
167 case GlobalValue::WeakODRLinkage:
168 case GlobalValue::LinkerPrivateLinkage:
169 if (MAI->getWeakDefDirective() != 0) {
171 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
172 // .weak_definition _foo
173 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
174 } else if (const char *LinkOnce = MAI->getLinkOnceDirective()) {
176 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
177 // FIXME: linkonce should be a section attribute, handled by COFF Section
179 // http://sourceware.org/binutils/docs-2.20/as/Linkonce.html#Linkonce
181 // FIXME: It would be nice to use .linkonce samesize for non-common
183 OutStreamer.EmitRawText(StringRef(LinkOnce));
186 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
189 case GlobalValue::DLLExportLinkage:
190 case GlobalValue::AppendingLinkage:
191 // FIXME: appending linkage variables should go into a section of
192 // their name or something. For now, just emit them as external.
193 case GlobalValue::ExternalLinkage:
194 // If external or appending, declare as a global symbol.
196 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
198 case GlobalValue::PrivateLinkage:
199 case GlobalValue::InternalLinkage:
202 llvm_unreachable("Unknown linkage type!");
207 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
208 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
209 if (!GV->hasInitializer()) // External globals require no code.
212 // Check to see if this is a special global used by LLVM, if so, emit it.
213 if (EmitSpecialLLVMGlobal(GV))
216 MCSymbol *GVSym = Mang->getSymbol(GV);
217 EmitVisibility(GVSym, GV->getVisibility());
219 if (MAI->hasDotTypeDotSizeDirective())
220 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
222 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
224 const TargetData *TD = TM.getTargetData();
225 unsigned Size = TD->getTypeAllocSize(GV->getType()->getElementType());
226 unsigned AlignLog = TD->getPreferredAlignmentLog(GV);
228 // Handle common and BSS local symbols (.lcomm).
229 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
230 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
233 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
234 /*PrintType=*/false, GV->getParent());
235 OutStreamer.GetCommentOS() << '\n';
238 // Handle common symbols.
239 if (GVKind.isCommon()) {
241 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
245 // Handle local BSS symbols.
246 if (MAI->hasMachoZeroFillDirective()) {
247 const MCSection *TheSection =
248 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
249 // .zerofill __DATA, __bss, _foo, 400, 5
250 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
254 if (MAI->hasLCOMMDirective()) {
256 OutStreamer.EmitLocalCommonSymbol(GVSym, Size);
261 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
263 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
267 const MCSection *TheSection =
268 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
270 // Handle the zerofill directive on darwin, which is a special form of BSS
272 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
274 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
275 // .zerofill __DATA, __common, _foo, 400, 5
276 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
280 OutStreamer.SwitchSection(TheSection);
282 EmitLinkage(GV->getLinkage(), GVSym);
283 EmitAlignment(AlignLog, GV);
286 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
287 /*PrintType=*/false, GV->getParent());
288 OutStreamer.GetCommentOS() << '\n';
290 OutStreamer.EmitLabel(GVSym);
292 EmitGlobalConstant(GV->getInitializer());
294 if (MAI->hasDotTypeDotSizeDirective())
296 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
298 OutStreamer.AddBlankLine();
301 /// EmitFunctionHeader - This method emits the header for the current
303 void AsmPrinter::EmitFunctionHeader() {
304 // Print out constants referenced by the function
307 // Print the 'header' of function.
308 const Function *F = MF->getFunction();
310 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
311 EmitVisibility(CurrentFnSym, F->getVisibility());
313 EmitLinkage(F->getLinkage(), CurrentFnSym);
314 EmitAlignment(MF->getAlignment(), F);
316 if (MAI->hasDotTypeDotSizeDirective())
317 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
320 WriteAsOperand(OutStreamer.GetCommentOS(), F,
321 /*PrintType=*/false, F->getParent());
322 OutStreamer.GetCommentOS() << '\n';
325 // Emit the CurrentFnSym. This is a virtual function to allow targets to
326 // do their wild and crazy things as required.
327 EmitFunctionEntryLabel();
329 // If the function had address-taken blocks that got deleted, then we have
330 // references to the dangling symbols. Emit them at the start of the function
331 // so that we don't get references to undefined symbols.
332 std::vector<MCSymbol*> DeadBlockSyms;
333 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
334 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
335 OutStreamer.AddComment("Address taken block that was later removed");
336 OutStreamer.EmitLabel(DeadBlockSyms[i]);
339 // Add some workaround for linkonce linkage on Cygwin\MinGW.
340 if (MAI->getLinkOnceDirective() != 0 &&
341 (F->hasLinkOnceLinkage() || F->hasWeakLinkage())) {
342 // FIXME: What is this?
344 OutContext.GetOrCreateSymbol(Twine("Lllvm$workaround$fake$stub$")+
345 CurrentFnSym->getName());
346 OutStreamer.EmitLabel(FakeStub);
349 // Emit pre-function debug and/or EH information.
350 if (DE) DE->BeginFunction(MF);
351 if (DD) DD->beginFunction(MF);
354 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
355 /// function. This can be overridden by targets as required to do custom stuff.
356 void AsmPrinter::EmitFunctionEntryLabel() {
357 OutStreamer.EmitLabel(CurrentFnSym);
361 /// EmitComments - Pretty-print comments for instructions.
362 static void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
363 const MachineFunction *MF = MI.getParent()->getParent();
364 const TargetMachine &TM = MF->getTarget();
366 DebugLoc DL = MI.getDebugLoc();
367 if (!DL.isUnknown()) { // Print source line info.
368 DIScope Scope(DL.getScope(MF->getFunction()->getContext()));
369 // Omit the directory, because it's likely to be long and uninteresting.
371 CommentOS << Scope.getFilename();
373 CommentOS << "<unknown>";
374 CommentOS << ':' << DL.getLine();
375 if (DL.getCol() != 0)
376 CommentOS << ':' << DL.getCol();
380 // Check for spills and reloads
383 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
385 // We assume a single instruction only has a spill or reload, not
387 const MachineMemOperand *MMO;
388 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
389 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
390 MMO = *MI.memoperands_begin();
391 CommentOS << MMO->getSize() << "-byte Reload\n";
393 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
394 if (FrameInfo->isSpillSlotObjectIndex(FI))
395 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
396 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
397 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
398 MMO = *MI.memoperands_begin();
399 CommentOS << MMO->getSize() << "-byte Spill\n";
401 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
402 if (FrameInfo->isSpillSlotObjectIndex(FI))
403 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
406 // Check for spill-induced copies
407 unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
408 if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg,
409 SrcSubIdx, DstSubIdx)) {
410 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
411 CommentOS << " Reload Reuse\n";
415 /// EmitImplicitDef - This method emits the specified machine instruction
416 /// that is an implicit def.
417 static void EmitImplicitDef(const MachineInstr *MI, AsmPrinter &AP) {
418 unsigned RegNo = MI->getOperand(0).getReg();
419 AP.OutStreamer.AddComment(Twine("implicit-def: ") +
420 AP.TM.getRegisterInfo()->getName(RegNo));
421 AP.OutStreamer.AddBlankLine();
424 static void EmitKill(const MachineInstr *MI, AsmPrinter &AP) {
425 std::string Str = "kill:";
426 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
427 const MachineOperand &Op = MI->getOperand(i);
428 assert(Op.isReg() && "KILL instruction must have only register operands");
430 Str += AP.TM.getRegisterInfo()->getName(Op.getReg());
431 Str += (Op.isDef() ? "<def>" : "<kill>");
433 AP.OutStreamer.AddComment(Str);
434 AP.OutStreamer.AddBlankLine();
437 /// EmitDebugValueComment - This method handles the target-independent form
438 /// of DBG_VALUE, returning true if it was able to do so. A false return
439 /// means the target will need to handle MI in EmitInstruction.
440 static bool EmitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
441 // This code handles only the 3-operand target-independent form.
442 if (MI->getNumOperands() != 3)
445 SmallString<128> Str;
446 raw_svector_ostream OS(Str);
447 OS << '\t' << AP.MAI->getCommentString() << "DEBUG_VALUE: ";
449 // cast away const; DIetc do not take const operands for some reason.
450 DIVariable V((MDNode*)(MI->getOperand(2).getMetadata()));
451 OS << V.getName() << " <- ";
453 // Register or immediate value. Register 0 means undef.
454 if (MI->getOperand(0).isFPImm()) {
455 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
456 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
457 OS << (double)APF.convertToFloat();
458 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
459 OS << APF.convertToDouble();
461 // There is no good way to print long double. Convert a copy to
462 // double. Ah well, it's only a comment.
464 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
466 OS << "(long double) " << APF.convertToDouble();
468 } else if (MI->getOperand(0).isImm()) {
469 OS << MI->getOperand(0).getImm();
470 } else if (MI->getOperand(0).isReg()) {
471 if (MI->getOperand(0).getReg() == 0) {
472 // Suppress offset, it is not meaningful here.
474 // NOTE: Want this comment at start of line, don't emit with AddComment.
475 AP.OutStreamer.EmitRawText(OS.str());
478 OS << AP.TM.getRegisterInfo()->getName(MI->getOperand(0).getReg());
480 llvm_unreachable("Unknown operand type");
482 OS << '+' << MI->getOperand(1).getImm();
483 // NOTE: Want this comment at start of line, don't emit with AddComment.
484 AP.OutStreamer.EmitRawText(OS.str());
488 /// EmitFunctionBody - This method emits the body and trailer for a
490 void AsmPrinter::EmitFunctionBody() {
491 // Emit target-specific gunk before the function body.
492 EmitFunctionBodyStart();
494 bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo();
496 // Print out code for the function.
497 bool HasAnyRealCode = false;
498 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
500 // Print a label for the basic block.
501 EmitBasicBlockStart(I);
502 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
504 // Print the assembly for the instruction.
506 HasAnyRealCode = true;
510 if (ShouldPrintDebugScopes)
514 EmitComments(*II, OutStreamer.GetCommentOS());
516 switch (II->getOpcode()) {
517 case TargetOpcode::DBG_LABEL:
518 case TargetOpcode::EH_LABEL:
519 case TargetOpcode::GC_LABEL:
520 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol());
522 case TargetOpcode::INLINEASM:
525 case TargetOpcode::DBG_VALUE:
527 if (!EmitDebugValueComment(II, *this))
531 case TargetOpcode::IMPLICIT_DEF:
532 if (isVerbose()) EmitImplicitDef(II, *this);
534 case TargetOpcode::KILL:
535 if (isVerbose()) EmitKill(II, *this);
542 if (ShouldPrintDebugScopes)
547 // If the function is empty and the object file uses .subsections_via_symbols,
548 // then we need to emit *something* to the function body to prevent the
549 // labels from collapsing together. Just emit a 0 byte.
550 if (MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)
551 OutStreamer.EmitIntValue(0, 1, 0/*addrspace*/);
553 // Emit target-specific gunk after the function body.
554 EmitFunctionBodyEnd();
556 // If the target wants a .size directive for the size of the function, emit
558 if (MAI->hasDotTypeDotSizeDirective()) {
559 // Create a symbol for the end of function, so we can get the size as
560 // difference between the function label and the temp label.
561 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
562 OutStreamer.EmitLabel(FnEndLabel);
564 const MCExpr *SizeExp =
565 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
566 MCSymbolRefExpr::Create(CurrentFnSym, OutContext),
568 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
571 // Emit post-function debug information.
572 if (DD) DD->endFunction(MF);
573 if (DE) DE->EndFunction();
576 // Print out jump tables referenced by the function.
579 OutStreamer.AddBlankLine();
583 bool AsmPrinter::doFinalization(Module &M) {
584 // Emit global variables.
585 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
587 EmitGlobalVariable(I);
589 // Finalize debug and EH information.
599 // If the target wants to know about weak references, print them all.
600 if (MAI->getWeakRefDirective()) {
601 // FIXME: This is not lazy, it would be nice to only print weak references
602 // to stuff that is actually used. Note that doing so would require targets
603 // to notice uses in operands (due to constant exprs etc). This should
604 // happen with the MC stuff eventually.
606 // Print out module-level global variables here.
607 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
609 if (!I->hasExternalWeakLinkage()) continue;
610 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
613 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
614 if (!I->hasExternalWeakLinkage()) continue;
615 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
619 if (MAI->hasSetDirective()) {
620 OutStreamer.AddBlankLine();
621 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
623 MCSymbol *Name = Mang->getSymbol(I);
625 const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
626 MCSymbol *Target = Mang->getSymbol(GV);
628 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
629 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
630 else if (I->hasWeakLinkage())
631 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
633 assert(I->hasLocalLinkage() && "Invalid alias linkage");
635 EmitVisibility(Name, I->getVisibility());
637 // Emit the directives as assignments aka .set:
638 OutStreamer.EmitAssignment(Name,
639 MCSymbolRefExpr::Create(Target, OutContext));
643 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
644 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
645 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
646 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
647 MP->finishAssembly(*this);
649 // If we don't have any trampolines, then we don't require stack memory
650 // to be executable. Some targets have a directive to declare this.
651 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
652 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
653 if (MCSection *S = MAI->getNonexecutableStackSection(OutContext))
654 OutStreamer.SwitchSection(S);
656 // Allow the target to emit any magic that it wants at the end of the file,
657 // after everything else has gone out.
660 delete Mang; Mang = 0;
663 OutStreamer.Finish();
667 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
669 // Get the function symbol.
670 CurrentFnSym = Mang->getSymbol(MF.getFunction());
673 LI = &getAnalysis<MachineLoopInfo>();
677 // SectionCPs - Keep track the alignment, constpool entries per Section.
681 SmallVector<unsigned, 4> CPEs;
682 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
686 /// EmitConstantPool - Print to the current output stream assembly
687 /// representations of the constants in the constant pool MCP. This is
688 /// used to print out constants which have been "spilled to memory" by
689 /// the code generator.
691 void AsmPrinter::EmitConstantPool() {
692 const MachineConstantPool *MCP = MF->getConstantPool();
693 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
694 if (CP.empty()) return;
696 // Calculate sections for constant pool entries. We collect entries to go into
697 // the same section together to reduce amount of section switch statements.
698 SmallVector<SectionCPs, 4> CPSections;
699 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
700 const MachineConstantPoolEntry &CPE = CP[i];
701 unsigned Align = CPE.getAlignment();
704 switch (CPE.getRelocationInfo()) {
705 default: llvm_unreachable("Unknown section kind");
706 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
708 Kind = SectionKind::getReadOnlyWithRelLocal();
711 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
712 case 4: Kind = SectionKind::getMergeableConst4(); break;
713 case 8: Kind = SectionKind::getMergeableConst8(); break;
714 case 16: Kind = SectionKind::getMergeableConst16();break;
715 default: Kind = SectionKind::getMergeableConst(); break;
719 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
721 // The number of sections are small, just do a linear search from the
722 // last section to the first.
724 unsigned SecIdx = CPSections.size();
725 while (SecIdx != 0) {
726 if (CPSections[--SecIdx].S == S) {
732 SecIdx = CPSections.size();
733 CPSections.push_back(SectionCPs(S, Align));
736 if (Align > CPSections[SecIdx].Alignment)
737 CPSections[SecIdx].Alignment = Align;
738 CPSections[SecIdx].CPEs.push_back(i);
741 // Now print stuff into the calculated sections.
742 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
743 OutStreamer.SwitchSection(CPSections[i].S);
744 EmitAlignment(Log2_32(CPSections[i].Alignment));
747 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
748 unsigned CPI = CPSections[i].CPEs[j];
749 MachineConstantPoolEntry CPE = CP[CPI];
751 // Emit inter-object padding for alignment.
752 unsigned AlignMask = CPE.getAlignment() - 1;
753 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
754 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/);
756 const Type *Ty = CPE.getType();
757 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
759 // Emit the label with a comment on it.
761 OutStreamer.GetCommentOS() << "constant pool ";
762 WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(),
763 MF->getFunction()->getParent());
764 OutStreamer.GetCommentOS() << '\n';
766 OutStreamer.EmitLabel(GetCPISymbol(CPI));
768 if (CPE.isMachineConstantPoolEntry())
769 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
771 EmitGlobalConstant(CPE.Val.ConstVal);
776 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
777 /// by the current function to the current output stream.
779 void AsmPrinter::EmitJumpTableInfo() {
780 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
781 if (MJTI == 0) return;
782 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
783 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
784 if (JT.empty()) return;
786 // Pick the directive to use to print the jump table entries, and switch to
787 // the appropriate section.
788 const Function *F = MF->getFunction();
789 bool JTInDiffSection = false;
790 if (// In PIC mode, we need to emit the jump table to the same section as the
791 // function body itself, otherwise the label differences won't make sense.
792 // FIXME: Need a better predicate for this: what about custom entries?
793 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
794 // We should also do if the section name is NULL or function is declared
795 // in discardable section
796 // FIXME: this isn't the right predicate, should be based on the MCSection
798 F->isWeakForLinker()) {
799 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
801 // Otherwise, drop it in the readonly section.
802 const MCSection *ReadOnlySection =
803 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
804 OutStreamer.SwitchSection(ReadOnlySection);
805 JTInDiffSection = true;
808 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData())));
810 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
811 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
813 // If this jump table was deleted, ignore it.
814 if (JTBBs.empty()) continue;
816 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
817 // .set directive for each unique entry. This reduces the number of
818 // relocations the assembler will generate for the jump table.
819 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
820 MAI->hasSetDirective()) {
821 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
822 const TargetLowering *TLI = TM.getTargetLowering();
823 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
824 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
825 const MachineBasicBlock *MBB = JTBBs[ii];
826 if (!EmittedSets.insert(MBB)) continue;
828 // .set LJTSet, LBB32-base
830 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
831 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
832 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
836 // On some targets (e.g. Darwin) we want to emit two consequtive labels
837 // before each jump table. The first label is never referenced, but tells
838 // the assembler and linker the extents of the jump table object. The
839 // second label is actually referenced by the code.
840 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
841 // FIXME: This doesn't have to have any specific name, just any randomly
842 // named and numbered 'l' label would work. Simplify GetJTISymbol.
843 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
845 OutStreamer.EmitLabel(GetJTISymbol(JTI));
847 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
848 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
852 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
854 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
855 const MachineBasicBlock *MBB,
856 unsigned UID) const {
857 const MCExpr *Value = 0;
858 switch (MJTI->getEntryKind()) {
859 case MachineJumpTableInfo::EK_Inline:
860 llvm_unreachable("Cannot emit EK_Inline jump table entry"); break;
861 case MachineJumpTableInfo::EK_Custom32:
862 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
865 case MachineJumpTableInfo::EK_BlockAddress:
866 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
868 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
870 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
871 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
872 // with a relocation as gp-relative, e.g.:
874 MCSymbol *MBBSym = MBB->getSymbol();
875 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
879 case MachineJumpTableInfo::EK_LabelDifference32: {
880 // EK_LabelDifference32 - Each entry is the address of the block minus
881 // the address of the jump table. This is used for PIC jump tables where
882 // gprel32 is not supported. e.g.:
883 // .word LBB123 - LJTI1_2
884 // If the .set directive is supported, this is emitted as:
885 // .set L4_5_set_123, LBB123 - LJTI1_2
886 // .word L4_5_set_123
888 // If we have emitted set directives for the jump table entries, print
889 // them rather than the entries themselves. If we're emitting PIC, then
890 // emit the table entries as differences between two text section labels.
891 if (MAI->hasSetDirective()) {
892 // If we used .set, reference the .set's symbol.
893 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
897 // Otherwise, use the difference as the jump table entry.
898 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
899 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
900 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
905 assert(Value && "Unknown entry kind!");
907 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData());
908 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0);
912 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
913 /// special global used by LLVM. If so, emit it and return true, otherwise
914 /// do nothing and return false.
915 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
916 if (GV->getName() == "llvm.used") {
917 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
918 EmitLLVMUsedList(GV->getInitializer());
922 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
923 if (GV->getSection() == "llvm.metadata" ||
924 GV->hasAvailableExternallyLinkage())
927 if (!GV->hasAppendingLinkage()) return false;
929 assert(GV->hasInitializer() && "Not a special LLVM global!");
931 const TargetData *TD = TM.getTargetData();
932 unsigned Align = Log2_32(TD->getPointerPrefAlignment());
933 if (GV->getName() == "llvm.global_ctors") {
934 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection());
935 EmitAlignment(Align, 0);
936 EmitXXStructorList(GV->getInitializer());
938 if (TM.getRelocationModel() == Reloc::Static &&
939 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
940 StringRef Sym(".constructors_used");
941 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
947 if (GV->getName() == "llvm.global_dtors") {
948 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection());
949 EmitAlignment(Align, 0);
950 EmitXXStructorList(GV->getInitializer());
952 if (TM.getRelocationModel() == Reloc::Static &&
953 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
954 StringRef Sym(".destructors_used");
955 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
964 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
965 /// global in the specified llvm.used list for which emitUsedDirectiveFor
966 /// is true, as being used with this directive.
967 void AsmPrinter::EmitLLVMUsedList(Constant *List) {
968 // Should be an array of 'i8*'.
969 ConstantArray *InitList = dyn_cast<ConstantArray>(List);
970 if (InitList == 0) return;
972 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
973 const GlobalValue *GV =
974 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
975 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
976 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip);
980 /// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the
981 /// function pointers, ignoring the init priority.
982 void AsmPrinter::EmitXXStructorList(Constant *List) {
983 // Should be an array of '{ int, void ()* }' structs. The first value is the
984 // init priority, which we ignore.
985 if (!isa<ConstantArray>(List)) return;
986 ConstantArray *InitList = cast<ConstantArray>(List);
987 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
988 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
989 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs.
991 if (CS->getOperand(1)->isNullValue())
992 return; // Found a null terminator, exit printing.
993 // Emit the function pointer.
994 EmitGlobalConstant(CS->getOperand(1));
998 //===--------------------------------------------------------------------===//
999 // Emission and print routines
1002 /// EmitInt8 - Emit a byte directive and value.
1004 void AsmPrinter::EmitInt8(int Value) const {
1005 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/);
1008 /// EmitInt16 - Emit a short directive and value.
1010 void AsmPrinter::EmitInt16(int Value) const {
1011 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/);
1014 /// EmitInt32 - Emit a long directive and value.
1016 void AsmPrinter::EmitInt32(int Value) const {
1017 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/);
1020 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
1021 /// in bytes of the directive is specified by Size and Hi/Lo specify the
1022 /// labels. This implicitly uses .set if it is available.
1023 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1024 unsigned Size) const {
1025 // Get the Hi-Lo expression.
1026 const MCExpr *Diff =
1027 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1028 MCSymbolRefExpr::Create(Lo, OutContext),
1031 if (!MAI->hasSetDirective()) {
1032 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/);
1036 // Otherwise, emit with .set (aka assignment).
1037 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1038 OutStreamer.EmitAssignment(SetLabel, Diff);
1039 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/);
1043 //===----------------------------------------------------------------------===//
1045 // EmitAlignment - Emit an alignment directive to the specified power of
1046 // two boundary. For example, if you pass in 3 here, you will get an 8
1047 // byte alignment. If a global value is specified, and if that global has
1048 // an explicit alignment requested, it will unconditionally override the
1049 // alignment request. However, if ForcedAlignBits is specified, this value
1050 // has final say: the ultimate alignment will be the max of ForcedAlignBits
1051 // and the alignment computed with NumBits and the global.
1053 // The algorithm is:
1055 // if (GV && GV->hasalignment) Align = GV->getalignment();
1056 // Align = std::max(Align, ForcedAlignBits);
1058 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
1059 unsigned ForcedAlignBits,
1060 bool UseFillExpr) const {
1061 if (GV && GV->getAlignment())
1062 NumBits = Log2_32(GV->getAlignment());
1063 NumBits = std::max(NumBits, ForcedAlignBits);
1065 if (NumBits == 0) return; // No need to emit alignment.
1067 if (getCurrentSection()->getKind().isText())
1068 OutStreamer.EmitCodeAlignment(1 << NumBits);
1070 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
1073 /// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
1075 static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) {
1076 MCContext &Ctx = AP.OutContext;
1078 if (CV->isNullValue() || isa<UndefValue>(CV))
1079 return MCConstantExpr::Create(0, Ctx);
1081 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1082 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1084 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1085 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx);
1086 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1087 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1089 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1091 llvm_unreachable("Unknown constant value to lower!");
1092 return MCConstantExpr::Create(0, Ctx);
1095 switch (CE->getOpcode()) {
1097 // If the code isn't optimized, there may be outstanding folding
1098 // opportunities. Attempt to fold the expression using TargetData as a
1099 // last resort before giving up.
1101 ConstantFoldConstantExpression(CE, AP.TM.getTargetData()))
1103 return LowerConstant(C, AP);
1107 llvm_unreachable("FIXME: Don't support this constant expr");
1108 case Instruction::GetElementPtr: {
1109 const TargetData &TD = *AP.TM.getTargetData();
1110 // Generate a symbolic expression for the byte address
1111 const Constant *PtrVal = CE->getOperand(0);
1112 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
1113 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0],
1116 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
1120 // Truncate/sext the offset to the pointer size.
1121 if (TD.getPointerSizeInBits() != 64) {
1122 int SExtAmount = 64-TD.getPointerSizeInBits();
1123 Offset = (Offset << SExtAmount) >> SExtAmount;
1126 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1130 case Instruction::Trunc:
1131 // We emit the value and depend on the assembler to truncate the generated
1132 // expression properly. This is important for differences between
1133 // blockaddress labels. Since the two labels are in the same function, it
1134 // is reasonable to treat their delta as a 32-bit value.
1136 case Instruction::BitCast:
1137 return LowerConstant(CE->getOperand(0), AP);
1139 case Instruction::IntToPtr: {
1140 const TargetData &TD = *AP.TM.getTargetData();
1141 // Handle casts to pointers by changing them into casts to the appropriate
1142 // integer type. This promotes constant folding and simplifies this code.
1143 Constant *Op = CE->getOperand(0);
1144 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
1146 return LowerConstant(Op, AP);
1149 case Instruction::PtrToInt: {
1150 const TargetData &TD = *AP.TM.getTargetData();
1151 // Support only foldable casts to/from pointers that can be eliminated by
1152 // changing the pointer to the appropriately sized integer type.
1153 Constant *Op = CE->getOperand(0);
1154 const Type *Ty = CE->getType();
1156 const MCExpr *OpExpr = LowerConstant(Op, AP);
1158 // We can emit the pointer value into this slot if the slot is an
1159 // integer slot equal to the size of the pointer.
1160 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
1163 // Otherwise the pointer is smaller than the resultant integer, mask off
1164 // the high bits so we are sure to get a proper truncation if the input is
1166 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
1167 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1168 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1171 // The MC library also has a right-shift operator, but it isn't consistently
1172 // signed or unsigned between different targets.
1173 case Instruction::Add:
1174 case Instruction::Sub:
1175 case Instruction::Mul:
1176 case Instruction::SDiv:
1177 case Instruction::SRem:
1178 case Instruction::Shl:
1179 case Instruction::And:
1180 case Instruction::Or:
1181 case Instruction::Xor: {
1182 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP);
1183 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP);
1184 switch (CE->getOpcode()) {
1185 default: llvm_unreachable("Unknown binary operator constant cast expr");
1186 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1187 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1188 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1189 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1190 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1191 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1192 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1193 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1194 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1200 static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
1202 if (AddrSpace != 0 || !CA->isString()) {
1203 // Not a string. Print the values in successive locations
1204 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1205 AP.EmitGlobalConstant(CA->getOperand(i), AddrSpace);
1209 // Otherwise, it can be emitted as .ascii.
1210 SmallVector<char, 128> TmpVec;
1211 TmpVec.reserve(CA->getNumOperands());
1212 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1213 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
1215 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace);
1218 static void EmitGlobalConstantVector(const ConstantVector *CV,
1219 unsigned AddrSpace, AsmPrinter &AP) {
1220 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1221 AP.EmitGlobalConstant(CV->getOperand(i), AddrSpace);
1224 static void EmitGlobalConstantStruct(const ConstantStruct *CS,
1225 unsigned AddrSpace, AsmPrinter &AP) {
1226 // Print the fields in successive locations. Pad to align if needed!
1227 const TargetData *TD = AP.TM.getTargetData();
1228 unsigned Size = TD->getTypeAllocSize(CS->getType());
1229 const StructLayout *Layout = TD->getStructLayout(CS->getType());
1230 uint64_t SizeSoFar = 0;
1231 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1232 const Constant *Field = CS->getOperand(i);
1234 // Check if padding is needed and insert one or more 0s.
1235 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
1236 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1237 - Layout->getElementOffset(i)) - FieldSize;
1238 SizeSoFar += FieldSize + PadSize;
1240 // Now print the actual field value.
1241 AP.EmitGlobalConstant(Field, AddrSpace);
1243 // Insert padding - this may include padding to increase the size of the
1244 // current field up to the ABI size (if the struct is not packed) as well
1245 // as padding to ensure that the next field starts at the right offset.
1246 AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
1248 assert(SizeSoFar == Layout->getSizeInBytes() &&
1249 "Layout of constant struct may be incorrect!");
1252 static void EmitGlobalConstantUnion(const ConstantUnion *CU,
1253 unsigned AddrSpace, AsmPrinter &AP) {
1254 const TargetData *TD = AP.TM.getTargetData();
1255 unsigned Size = TD->getTypeAllocSize(CU->getType());
1257 const Constant *Contents = CU->getOperand(0);
1258 unsigned FilledSize = TD->getTypeAllocSize(Contents->getType());
1260 // Print the actually filled part
1261 AP.EmitGlobalConstant(Contents, AddrSpace);
1263 // And pad with enough zeroes
1264 AP.OutStreamer.EmitZeros(Size-FilledSize, AddrSpace);
1267 static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
1269 // FP Constants are printed as integer constants to avoid losing
1271 if (CFP->getType()->isDoubleTy()) {
1272 if (AP.isVerbose()) {
1273 double Val = CFP->getValueAPF().convertToDouble();
1274 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n';
1277 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1278 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1282 if (CFP->getType()->isFloatTy()) {
1283 if (AP.isVerbose()) {
1284 float Val = CFP->getValueAPF().convertToFloat();
1285 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n';
1287 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1288 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace);
1292 if (CFP->getType()->isX86_FP80Ty()) {
1293 // all long double variants are printed as hex
1294 // API needed to prevent premature destruction
1295 APInt API = CFP->getValueAPF().bitcastToAPInt();
1296 const uint64_t *p = API.getRawData();
1297 if (AP.isVerbose()) {
1298 // Convert to double so we can print the approximate val as a comment.
1299 APFloat DoubleVal = CFP->getValueAPF();
1301 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1303 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= "
1304 << DoubleVal.convertToDouble() << '\n';
1307 if (AP.TM.getTargetData()->isBigEndian()) {
1308 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1309 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1311 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1312 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1315 // Emit the tail padding for the long double.
1316 const TargetData &TD = *AP.TM.getTargetData();
1317 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
1318 TD.getTypeStoreSize(CFP->getType()), AddrSpace);
1322 assert(CFP->getType()->isPPC_FP128Ty() &&
1323 "Floating point constant type not handled");
1324 // All long double variants are printed as hex
1325 // API needed to prevent premature destruction.
1326 APInt API = CFP->getValueAPF().bitcastToAPInt();
1327 const uint64_t *p = API.getRawData();
1328 if (AP.TM.getTargetData()->isBigEndian()) {
1329 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1330 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1332 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1333 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1337 static void EmitGlobalConstantLargeInt(const ConstantInt *CI,
1338 unsigned AddrSpace, AsmPrinter &AP) {
1339 const TargetData *TD = AP.TM.getTargetData();
1340 unsigned BitWidth = CI->getBitWidth();
1341 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
1343 // We don't expect assemblers to support integer data directives
1344 // for more than 64 bits, so we emit the data in at most 64-bit
1345 // quantities at a time.
1346 const uint64_t *RawData = CI->getValue().getRawData();
1347 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1348 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1349 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1353 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1354 void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1355 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) {
1356 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1357 if (Size == 0) Size = 1; // An empty "_foo:" followed by a section is undef.
1358 return OutStreamer.EmitZeros(Size, AddrSpace);
1361 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1362 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1369 OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue());
1370 OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1373 EmitGlobalConstantLargeInt(CI, AddrSpace, *this);
1378 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1379 return EmitGlobalConstantArray(CVA, AddrSpace, *this);
1381 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1382 return EmitGlobalConstantStruct(CVS, AddrSpace, *this);
1384 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1385 return EmitGlobalConstantFP(CFP, AddrSpace, *this);
1387 if (isa<ConstantPointerNull>(CV)) {
1388 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1389 OutStreamer.EmitIntValue(0, Size, AddrSpace);
1393 if (const ConstantUnion *CVU = dyn_cast<ConstantUnion>(CV))
1394 return EmitGlobalConstantUnion(CVU, AddrSpace, *this);
1396 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1397 return EmitGlobalConstantVector(V, AddrSpace, *this);
1399 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1400 // thread the streamer with EmitValue.
1401 OutStreamer.EmitValue(LowerConstant(CV, *this),
1402 TM.getTargetData()->getTypeAllocSize(CV->getType()),
1406 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1407 // Target doesn't support this yet!
1408 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1411 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1413 OS << '+' << Offset;
1414 else if (Offset < 0)
1418 //===----------------------------------------------------------------------===//
1419 // Symbol Lowering Routines.
1420 //===----------------------------------------------------------------------===//
1422 /// GetTempSymbol - Return the MCSymbol corresponding to the assembler
1423 /// temporary label with the specified stem and unique ID.
1424 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const {
1425 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) +
1429 /// GetTempSymbol - Return an assembler temporary label with the specified
1431 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const {
1432 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix())+
1437 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
1438 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
1441 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
1442 return MMI->getAddrLabelSymbol(BB);
1445 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1446 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1447 return OutContext.GetOrCreateSymbol
1448 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
1449 + "_" + Twine(CPID));
1452 /// GetJTISymbol - Return the symbol for the specified jump table entry.
1453 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1454 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
1457 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
1458 /// FIXME: privatize to AsmPrinter.
1459 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
1460 return OutContext.GetOrCreateSymbol
1461 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
1462 Twine(UID) + "_set_" + Twine(MBBID));
1465 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1466 /// global value name as its base, with the specified suffix, and where the
1467 /// symbol is forced to have private linkage if ForcePrivate is true.
1468 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1470 bool ForcePrivate) const {
1471 SmallString<60> NameStr;
1472 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1473 NameStr.append(Suffix.begin(), Suffix.end());
1474 return OutContext.GetOrCreateSymbol(NameStr.str());
1477 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
1479 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
1480 SmallString<60> NameStr;
1481 Mang->getNameWithPrefix(NameStr, Sym);
1482 return OutContext.GetOrCreateSymbol(NameStr.str());
1487 /// PrintParentLoopComment - Print comments about parent loops of this one.
1488 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1489 unsigned FunctionNumber) {
1490 if (Loop == 0) return;
1491 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
1492 OS.indent(Loop->getLoopDepth()*2)
1493 << "Parent Loop BB" << FunctionNumber << "_"
1494 << Loop->getHeader()->getNumber()
1495 << " Depth=" << Loop->getLoopDepth() << '\n';
1499 /// PrintChildLoopComment - Print comments about child loops within
1500 /// the loop for this basic block, with nesting.
1501 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1502 unsigned FunctionNumber) {
1503 // Add child loop information
1504 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
1505 OS.indent((*CL)->getLoopDepth()*2)
1506 << "Child Loop BB" << FunctionNumber << "_"
1507 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
1509 PrintChildLoopComment(OS, *CL, FunctionNumber);
1513 /// EmitBasicBlockLoopComments - Pretty-print comments for basic blocks.
1514 static void EmitBasicBlockLoopComments(const MachineBasicBlock &MBB,
1515 const MachineLoopInfo *LI,
1516 const AsmPrinter &AP) {
1517 // Add loop depth information
1518 const MachineLoop *Loop = LI->getLoopFor(&MBB);
1519 if (Loop == 0) return;
1521 MachineBasicBlock *Header = Loop->getHeader();
1522 assert(Header && "No header for loop");
1524 // If this block is not a loop header, just print out what is the loop header
1526 if (Header != &MBB) {
1527 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
1528 Twine(AP.getFunctionNumber())+"_" +
1529 Twine(Loop->getHeader()->getNumber())+
1530 " Depth="+Twine(Loop->getLoopDepth()));
1534 // Otherwise, it is a loop header. Print out information about child and
1536 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
1538 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
1541 OS.indent(Loop->getLoopDepth()*2-2);
1546 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
1548 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
1552 /// EmitBasicBlockStart - This method prints the label for the specified
1553 /// MachineBasicBlock, an alignment (if present) and a comment describing
1554 /// it if appropriate.
1555 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
1556 // Emit an alignment directive for this block, if needed.
1557 if (unsigned Align = MBB->getAlignment())
1558 EmitAlignment(Log2_32(Align));
1560 // If the block has its address taken, emit any labels that were used to
1561 // reference the block. It is possible that there is more than one label
1562 // here, because multiple LLVM BB's may have been RAUW'd to this block after
1563 // the references were generated.
1564 if (MBB->hasAddressTaken()) {
1565 const BasicBlock *BB = MBB->getBasicBlock();
1567 OutStreamer.AddComment("Block address taken");
1569 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
1571 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
1572 OutStreamer.EmitLabel(Syms[i]);
1575 // Print the main label for the block.
1576 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
1577 if (isVerbose() && OutStreamer.hasRawTextSupport()) {
1578 if (const BasicBlock *BB = MBB->getBasicBlock())
1580 OutStreamer.AddComment("%" + BB->getName());
1582 EmitBasicBlockLoopComments(*MBB, LI, *this);
1584 // NOTE: Want this comment at start of line, don't emit with AddComment.
1585 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" +
1586 Twine(MBB->getNumber()) + ":");
1590 if (const BasicBlock *BB = MBB->getBasicBlock())
1592 OutStreamer.AddComment("%" + BB->getName());
1593 EmitBasicBlockLoopComments(*MBB, LI, *this);
1596 OutStreamer.EmitLabel(MBB->getSymbol());
1600 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility) const {
1601 MCSymbolAttr Attr = MCSA_Invalid;
1603 switch (Visibility) {
1605 case GlobalValue::HiddenVisibility:
1606 Attr = MAI->getHiddenVisibilityAttr();
1608 case GlobalValue::ProtectedVisibility:
1609 Attr = MAI->getProtectedVisibilityAttr();
1613 if (Attr != MCSA_Invalid)
1614 OutStreamer.EmitSymbolAttribute(Sym, Attr);
1617 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
1618 /// exactly one predecessor and the control transfer mechanism between
1619 /// the predecessor and this block is a fall-through.
1621 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
1622 // If this is a landing pad, it isn't a fall through. If it has no preds,
1623 // then nothing falls through to it.
1624 if (MBB->isLandingPad() || MBB->pred_empty())
1627 // If there isn't exactly one predecessor, it can't be a fall through.
1628 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
1630 if (PI2 != MBB->pred_end())
1633 // The predecessor has to be immediately before this block.
1634 const MachineBasicBlock *Pred = *PI;
1636 if (!Pred->isLayoutSuccessor(MBB))
1639 // If the block is completely empty, then it definitely does fall through.
1643 // Otherwise, check the last instruction.
1644 const MachineInstr &LastInst = Pred->back();
1645 return !LastInst.getDesc().isBarrier();
1650 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1651 if (!S->usesMetadata())
1654 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
1655 gcp_map_type::iterator GCPI = GCMap.find(S);
1656 if (GCPI != GCMap.end())
1657 return GCPI->second;
1659 const char *Name = S->getName().c_str();
1661 for (GCMetadataPrinterRegistry::iterator
1662 I = GCMetadataPrinterRegistry::begin(),
1663 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1664 if (strcmp(Name, I->getName()) == 0) {
1665 GCMetadataPrinter *GMP = I->instantiate();
1667 GCMap.insert(std::make_pair(S, GMP));
1671 llvm_report_error("no GCMetadataPrinter registered for GC: " + Twine(Name));