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 "llvm/Assembly/Writer.h"
17 #include "llvm/DerivedTypes.h"
18 #include "llvm/Constants.h"
19 #include "llvm/Module.h"
20 #include "llvm/CodeGen/DwarfWriter.h"
21 #include "llvm/CodeGen/GCMetadataPrinter.h"
22 #include "llvm/CodeGen/MachineConstantPool.h"
23 #include "llvm/CodeGen/MachineFrameInfo.h"
24 #include "llvm/CodeGen/MachineFunction.h"
25 #include "llvm/CodeGen/MachineJumpTableInfo.h"
26 #include "llvm/CodeGen/MachineLoopInfo.h"
27 #include "llvm/CodeGen/MachineModuleInfo.h"
28 #include "llvm/Analysis/ConstantFolding.h"
29 #include "llvm/Analysis/DebugInfo.h"
30 #include "llvm/MC/MCContext.h"
31 #include "llvm/MC/MCExpr.h"
32 #include "llvm/MC/MCInst.h"
33 #include "llvm/MC/MCSection.h"
34 #include "llvm/MC/MCStreamer.h"
35 #include "llvm/MC/MCSymbol.h"
36 #include "llvm/MC/MCAsmInfo.h"
37 #include "llvm/Target/Mangler.h"
38 #include "llvm/Target/TargetData.h"
39 #include "llvm/Target/TargetInstrInfo.h"
40 #include "llvm/Target/TargetLowering.h"
41 #include "llvm/Target/TargetLoweringObjectFile.h"
42 #include "llvm/Target/TargetOptions.h"
43 #include "llvm/Target/TargetRegisterInfo.h"
44 #include "llvm/ADT/SmallPtrSet.h"
45 #include "llvm/ADT/SmallString.h"
46 #include "llvm/ADT/Statistic.h"
47 #include "llvm/Support/CommandLine.h"
48 #include "llvm/Support/Debug.h"
49 #include "llvm/Support/ErrorHandling.h"
50 #include "llvm/Support/Format.h"
51 #include "llvm/Support/FormattedStream.h"
55 STATISTIC(EmittedInsts, "Number of machine instrs printed");
57 char AsmPrinter::ID = 0;
59 AsmPrinter::AsmPrinter(formatted_raw_ostream &o, TargetMachine &tm,
61 : MachineFunctionPass(&ID), O(o),
62 TM(tm), MAI(tm.getMCAsmInfo()), TRI(tm.getRegisterInfo()),
63 OutContext(Streamer.getContext()),
64 OutStreamer(Streamer),
65 LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {
67 VerboseAsm = Streamer.isVerboseAsm();
70 AsmPrinter::~AsmPrinter() {
71 for (gcp_iterator I = GCMetadataPrinters.begin(),
72 E = GCMetadataPrinters.end(); I != E; ++I)
78 /// getFunctionNumber - Return a unique ID for the current function.
80 unsigned AsmPrinter::getFunctionNumber() const {
81 return MF->getFunctionNumber();
84 TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
85 return TM.getTargetLowering()->getObjFileLowering();
88 /// getCurrentSection() - Return the current section we are emitting to.
89 const MCSection *AsmPrinter::getCurrentSection() const {
90 return OutStreamer.getCurrentSection();
94 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
96 MachineFunctionPass::getAnalysisUsage(AU);
97 AU.addRequired<MachineModuleInfo>();
98 AU.addRequired<GCModuleInfo>();
100 AU.addRequired<MachineLoopInfo>();
103 bool AsmPrinter::doInitialization(Module &M) {
104 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
105 MMI->AnalyzeModule(M);
107 // Initialize TargetLoweringObjectFile.
108 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
109 .Initialize(OutContext, TM);
111 Mang = new Mangler(OutContext, *TM.getTargetData());
113 // Allow the target to emit any magic that it wants at the start of the file.
114 EmitStartOfAsmFile(M);
116 // Very minimal debug info. It is ignored if we emit actual debug info. If we
117 // don't, this at least helps the user find where a global came from.
118 if (MAI->hasSingleParameterDotFile()) {
120 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
123 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
124 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
125 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
126 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
127 MP->beginAssembly(O, *this, *MAI);
129 if (!M.getModuleInlineAsm().empty())
130 O << MAI->getCommentString() << " Start of file scope inline assembly\n"
131 << M.getModuleInlineAsm()
132 << '\n' << MAI->getCommentString()
133 << " End of file scope inline assembly\n";
135 DW = getAnalysisIfAvailable<DwarfWriter>();
137 DW->BeginModule(&M, MMI, O, this, MAI);
142 void AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const {
143 switch ((GlobalValue::LinkageTypes)Linkage) {
144 case GlobalValue::CommonLinkage:
145 case GlobalValue::LinkOnceAnyLinkage:
146 case GlobalValue::LinkOnceODRLinkage:
147 case GlobalValue::WeakAnyLinkage:
148 case GlobalValue::WeakODRLinkage:
149 case GlobalValue::LinkerPrivateLinkage:
150 if (MAI->getWeakDefDirective() != 0) {
152 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
153 // .weak_definition _foo
154 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
155 } else if (const char *LinkOnce = MAI->getLinkOnceDirective()) {
157 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
158 // FIXME: linkonce should be a section attribute, handled by COFF Section
160 // http://sourceware.org/binutils/docs-2.20/as/Linkonce.html#Linkonce
162 // FIXME: It would be nice to use .linkonce samesize for non-common
167 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
170 case GlobalValue::DLLExportLinkage:
171 case GlobalValue::AppendingLinkage:
172 // FIXME: appending linkage variables should go into a section of
173 // their name or something. For now, just emit them as external.
174 case GlobalValue::ExternalLinkage:
175 // If external or appending, declare as a global symbol.
177 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
179 case GlobalValue::PrivateLinkage:
180 case GlobalValue::InternalLinkage:
183 llvm_unreachable("Unknown linkage type!");
188 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
189 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
190 if (!GV->hasInitializer()) // External globals require no code.
193 // Check to see if this is a special global used by LLVM, if so, emit it.
194 if (EmitSpecialLLVMGlobal(GV))
197 MCSymbol *GVSym = Mang->getSymbol(GV);
198 EmitVisibility(GVSym, GV->getVisibility());
200 if (MAI->hasDotTypeDotSizeDirective())
201 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
203 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
205 const TargetData *TD = TM.getTargetData();
206 unsigned Size = TD->getTypeAllocSize(GV->getType()->getElementType());
207 unsigned AlignLog = TD->getPreferredAlignmentLog(GV);
209 // Handle common and BSS local symbols (.lcomm).
210 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
211 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
214 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
215 /*PrintType=*/false, GV->getParent());
216 OutStreamer.GetCommentOS() << '\n';
219 // Handle common symbols.
220 if (GVKind.isCommon()) {
222 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
226 // Handle local BSS symbols.
227 if (MAI->hasMachoZeroFillDirective()) {
228 const MCSection *TheSection =
229 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
230 // .zerofill __DATA, __bss, _foo, 400, 5
231 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
235 if (MAI->hasLCOMMDirective()) {
237 OutStreamer.EmitLocalCommonSymbol(GVSym, Size);
242 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
244 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
248 const MCSection *TheSection =
249 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
251 // Handle the zerofill directive on darwin, which is a special form of BSS
253 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
255 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
256 // .zerofill __DATA, __common, _foo, 400, 5
257 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
261 OutStreamer.SwitchSection(TheSection);
263 EmitLinkage(GV->getLinkage(), GVSym);
264 EmitAlignment(AlignLog, GV);
267 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
268 /*PrintType=*/false, GV->getParent());
269 OutStreamer.GetCommentOS() << '\n';
271 OutStreamer.EmitLabel(GVSym);
273 EmitGlobalConstant(GV->getInitializer());
275 if (MAI->hasDotTypeDotSizeDirective())
277 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
279 OutStreamer.AddBlankLine();
282 /// EmitFunctionHeader - This method emits the header for the current
284 void AsmPrinter::EmitFunctionHeader() {
285 // Print out constants referenced by the function
288 // Print the 'header' of function.
289 const Function *F = MF->getFunction();
291 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
292 EmitVisibility(CurrentFnSym, F->getVisibility());
294 EmitLinkage(F->getLinkage(), CurrentFnSym);
295 EmitAlignment(MF->getAlignment(), F);
297 if (MAI->hasDotTypeDotSizeDirective())
298 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
301 WriteAsOperand(OutStreamer.GetCommentOS(), F,
302 /*PrintType=*/false, F->getParent());
303 OutStreamer.GetCommentOS() << '\n';
306 // Emit the CurrentFnSym. This is a virtual function to allow targets to
307 // do their wild and crazy things as required.
308 EmitFunctionEntryLabel();
310 // If the function had address-taken blocks that got deleted, then we have
311 // references to the dangling symbols. Emit them at the start of the function
312 // so that we don't get references to undefined symbols.
313 std::vector<MCSymbol*> DeadBlockSyms;
314 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
315 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
316 OutStreamer.AddComment("Address taken block that was later removed");
317 OutStreamer.EmitLabel(DeadBlockSyms[i]);
320 // Add some workaround for linkonce linkage on Cygwin\MinGW.
321 if (MAI->getLinkOnceDirective() != 0 &&
322 (F->hasLinkOnceLinkage() || F->hasWeakLinkage()))
323 // FIXME: What is this?
324 O << "Lllvm$workaround$fake$stub$" << *CurrentFnSym << ":\n";
326 // Emit pre-function debug and/or EH information.
327 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
328 DW->BeginFunction(MF);
331 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
332 /// function. This can be overridden by targets as required to do custom stuff.
333 void AsmPrinter::EmitFunctionEntryLabel() {
334 OutStreamer.EmitLabel(CurrentFnSym);
338 /// EmitComments - Pretty-print comments for instructions.
339 static void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
340 const MachineFunction *MF = MI.getParent()->getParent();
341 const TargetMachine &TM = MF->getTarget();
343 DebugLoc DL = MI.getDebugLoc();
344 if (!DL.isUnknown()) { // Print source line info.
345 DIScope Scope(DL.getScope(MF->getFunction()->getContext()));
346 // Omit the directory, because it's likely to be long and uninteresting.
348 CommentOS << Scope.getFilename();
350 CommentOS << "<unknown>";
351 CommentOS << ':' << DL.getLine();
352 if (DL.getCol() != 0)
353 CommentOS << ':' << DL.getCol();
357 // Check for spills and reloads
360 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
362 // We assume a single instruction only has a spill or reload, not
364 const MachineMemOperand *MMO;
365 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
366 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
367 MMO = *MI.memoperands_begin();
368 CommentOS << MMO->getSize() << "-byte Reload\n";
370 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
371 if (FrameInfo->isSpillSlotObjectIndex(FI))
372 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
373 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
374 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
375 MMO = *MI.memoperands_begin();
376 CommentOS << MMO->getSize() << "-byte Spill\n";
378 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
379 if (FrameInfo->isSpillSlotObjectIndex(FI))
380 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
383 // Check for spill-induced copies
384 unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
385 if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg,
386 SrcSubIdx, DstSubIdx)) {
387 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
388 CommentOS << " Reload Reuse\n";
394 /// EmitFunctionBody - This method emits the body and trailer for a
396 void AsmPrinter::EmitFunctionBody() {
397 // Emit target-specific gunk before the function body.
398 EmitFunctionBodyStart();
400 // Print out code for the function.
401 bool HasAnyRealCode = false;
402 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
404 // Print a label for the basic block.
405 EmitBasicBlockStart(I);
406 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
408 // Print the assembly for the instruction.
410 HasAnyRealCode = true;
414 // FIXME: Clean up processDebugLoc.
415 processDebugLoc(II, true);
418 EmitComments(*II, OutStreamer.GetCommentOS());
420 switch (II->getOpcode()) {
421 case TargetOpcode::DBG_LABEL:
422 case TargetOpcode::EH_LABEL:
423 case TargetOpcode::GC_LABEL:
426 case TargetOpcode::INLINEASM:
429 case TargetOpcode::IMPLICIT_DEF:
430 printImplicitDef(II);
432 case TargetOpcode::KILL:
440 // FIXME: Clean up processDebugLoc.
441 processDebugLoc(II, false);
445 // If the function is empty and the object file uses .subsections_via_symbols,
446 // then we need to emit *something* to the function body to prevent the
447 // labels from collapsing together. Just emit a 0 byte.
448 if (MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)
449 OutStreamer.EmitIntValue(0, 1, 0/*addrspace*/);
451 // Emit target-specific gunk after the function body.
452 EmitFunctionBodyEnd();
454 if (MAI->hasDotTypeDotSizeDirective())
455 O << "\t.size\t" << *CurrentFnSym << ", .-" << *CurrentFnSym << '\n';
457 // Emit post-function debug information.
458 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
461 // Print out jump tables referenced by the function.
464 OutStreamer.AddBlankLine();
468 bool AsmPrinter::doFinalization(Module &M) {
469 // Emit global variables.
470 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
472 EmitGlobalVariable(I);
474 // Emit final debug information.
475 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
478 // If the target wants to know about weak references, print them all.
479 if (MAI->getWeakRefDirective()) {
480 // FIXME: This is not lazy, it would be nice to only print weak references
481 // to stuff that is actually used. Note that doing so would require targets
482 // to notice uses in operands (due to constant exprs etc). This should
483 // happen with the MC stuff eventually.
485 // Print out module-level global variables here.
486 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
488 if (!I->hasExternalWeakLinkage()) continue;
489 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
492 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
493 if (!I->hasExternalWeakLinkage()) continue;
494 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
498 if (MAI->hasSetDirective()) {
499 OutStreamer.AddBlankLine();
500 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
502 MCSymbol *Name = Mang->getSymbol(I);
504 const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
505 MCSymbol *Target = Mang->getSymbol(GV);
507 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
508 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
509 else if (I->hasWeakLinkage())
510 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
512 assert(I->hasLocalLinkage() && "Invalid alias linkage");
514 EmitVisibility(Name, I->getVisibility());
516 // Emit the directives as assignments aka .set:
517 OutStreamer.EmitAssignment(Name,
518 MCSymbolRefExpr::Create(Target, OutContext));
522 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
523 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
524 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
525 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
526 MP->finishAssembly(O, *this, *MAI);
528 // If we don't have any trampolines, then we don't require stack memory
529 // to be executable. Some targets have a directive to declare this.
530 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
531 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
532 if (MCSection *S = MAI->getNonexecutableStackSection(OutContext))
533 OutStreamer.SwitchSection(S);
535 // Allow the target to emit any magic that it wants at the end of the file,
536 // after everything else has gone out.
539 delete Mang; Mang = 0;
542 OutStreamer.Finish();
546 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
548 // Get the function symbol.
549 CurrentFnSym = Mang->getSymbol(MF.getFunction());
552 LI = &getAnalysis<MachineLoopInfo>();
556 // SectionCPs - Keep track the alignment, constpool entries per Section.
560 SmallVector<unsigned, 4> CPEs;
561 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
565 /// EmitConstantPool - Print to the current output stream assembly
566 /// representations of the constants in the constant pool MCP. This is
567 /// used to print out constants which have been "spilled to memory" by
568 /// the code generator.
570 void AsmPrinter::EmitConstantPool() {
571 const MachineConstantPool *MCP = MF->getConstantPool();
572 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
573 if (CP.empty()) return;
575 // Calculate sections for constant pool entries. We collect entries to go into
576 // the same section together to reduce amount of section switch statements.
577 SmallVector<SectionCPs, 4> CPSections;
578 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
579 const MachineConstantPoolEntry &CPE = CP[i];
580 unsigned Align = CPE.getAlignment();
583 switch (CPE.getRelocationInfo()) {
584 default: llvm_unreachable("Unknown section kind");
585 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
587 Kind = SectionKind::getReadOnlyWithRelLocal();
590 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
591 case 4: Kind = SectionKind::getMergeableConst4(); break;
592 case 8: Kind = SectionKind::getMergeableConst8(); break;
593 case 16: Kind = SectionKind::getMergeableConst16();break;
594 default: Kind = SectionKind::getMergeableConst(); break;
598 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
600 // The number of sections are small, just do a linear search from the
601 // last section to the first.
603 unsigned SecIdx = CPSections.size();
604 while (SecIdx != 0) {
605 if (CPSections[--SecIdx].S == S) {
611 SecIdx = CPSections.size();
612 CPSections.push_back(SectionCPs(S, Align));
615 if (Align > CPSections[SecIdx].Alignment)
616 CPSections[SecIdx].Alignment = Align;
617 CPSections[SecIdx].CPEs.push_back(i);
620 // Now print stuff into the calculated sections.
621 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
622 OutStreamer.SwitchSection(CPSections[i].S);
623 EmitAlignment(Log2_32(CPSections[i].Alignment));
626 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
627 unsigned CPI = CPSections[i].CPEs[j];
628 MachineConstantPoolEntry CPE = CP[CPI];
630 // Emit inter-object padding for alignment.
631 unsigned AlignMask = CPE.getAlignment() - 1;
632 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
633 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/);
635 const Type *Ty = CPE.getType();
636 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
638 // Emit the label with a comment on it.
640 OutStreamer.GetCommentOS() << "constant pool ";
641 WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(),
642 MF->getFunction()->getParent());
643 OutStreamer.GetCommentOS() << '\n';
645 OutStreamer.EmitLabel(GetCPISymbol(CPI));
647 if (CPE.isMachineConstantPoolEntry())
648 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
650 EmitGlobalConstant(CPE.Val.ConstVal);
655 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
656 /// by the current function to the current output stream.
658 void AsmPrinter::EmitJumpTableInfo() {
659 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
660 if (MJTI == 0) return;
661 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
662 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
663 if (JT.empty()) return;
665 // Pick the directive to use to print the jump table entries, and switch to
666 // the appropriate section.
667 const Function *F = MF->getFunction();
668 bool JTInDiffSection = false;
669 if (// In PIC mode, we need to emit the jump table to the same section as the
670 // function body itself, otherwise the label differences won't make sense.
671 // FIXME: Need a better predicate for this: what about custom entries?
672 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
673 // We should also do if the section name is NULL or function is declared
674 // in discardable section
675 // FIXME: this isn't the right predicate, should be based on the MCSection
677 F->isWeakForLinker()) {
678 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
680 // Otherwise, drop it in the readonly section.
681 const MCSection *ReadOnlySection =
682 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
683 OutStreamer.SwitchSection(ReadOnlySection);
684 JTInDiffSection = true;
687 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData())));
689 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
690 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
692 // If this jump table was deleted, ignore it.
693 if (JTBBs.empty()) continue;
695 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
696 // .set directive for each unique entry. This reduces the number of
697 // relocations the assembler will generate for the jump table.
698 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
699 MAI->hasSetDirective()) {
700 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
701 const TargetLowering *TLI = TM.getTargetLowering();
702 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
703 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
704 const MachineBasicBlock *MBB = JTBBs[ii];
705 if (!EmittedSets.insert(MBB)) continue;
707 // .set LJTSet, LBB32-base
709 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
710 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
711 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
715 // On some targets (e.g. Darwin) we want to emit two consequtive labels
716 // before each jump table. The first label is never referenced, but tells
717 // the assembler and linker the extents of the jump table object. The
718 // second label is actually referenced by the code.
719 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
720 // FIXME: This doesn't have to have any specific name, just any randomly
721 // named and numbered 'l' label would work. Simplify GetJTISymbol.
722 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
724 OutStreamer.EmitLabel(GetJTISymbol(JTI));
726 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
727 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
731 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
733 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
734 const MachineBasicBlock *MBB,
735 unsigned UID) const {
736 const MCExpr *Value = 0;
737 switch (MJTI->getEntryKind()) {
738 case MachineJumpTableInfo::EK_Inline:
739 llvm_unreachable("Cannot emit EK_Inline jump table entry"); break;
740 case MachineJumpTableInfo::EK_Custom32:
741 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
744 case MachineJumpTableInfo::EK_BlockAddress:
745 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
747 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
749 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
750 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
751 // with a relocation as gp-relative, e.g.:
753 MCSymbol *MBBSym = MBB->getSymbol();
754 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
758 case MachineJumpTableInfo::EK_LabelDifference32: {
759 // EK_LabelDifference32 - Each entry is the address of the block minus
760 // the address of the jump table. This is used for PIC jump tables where
761 // gprel32 is not supported. e.g.:
762 // .word LBB123 - LJTI1_2
763 // If the .set directive is supported, this is emitted as:
764 // .set L4_5_set_123, LBB123 - LJTI1_2
765 // .word L4_5_set_123
767 // If we have emitted set directives for the jump table entries, print
768 // them rather than the entries themselves. If we're emitting PIC, then
769 // emit the table entries as differences between two text section labels.
770 if (MAI->hasSetDirective()) {
771 // If we used .set, reference the .set's symbol.
772 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
776 // Otherwise, use the difference as the jump table entry.
777 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
778 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
779 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
784 assert(Value && "Unknown entry kind!");
786 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData());
787 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0);
791 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
792 /// special global used by LLVM. If so, emit it and return true, otherwise
793 /// do nothing and return false.
794 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
795 if (GV->getName() == "llvm.used") {
796 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
797 EmitLLVMUsedList(GV->getInitializer());
801 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
802 if (GV->getSection() == "llvm.metadata" ||
803 GV->hasAvailableExternallyLinkage())
806 if (!GV->hasAppendingLinkage()) return false;
808 assert(GV->hasInitializer() && "Not a special LLVM global!");
810 const TargetData *TD = TM.getTargetData();
811 unsigned Align = Log2_32(TD->getPointerPrefAlignment());
812 if (GV->getName() == "llvm.global_ctors") {
813 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection());
814 EmitAlignment(Align, 0);
815 EmitXXStructorList(GV->getInitializer());
817 if (TM.getRelocationModel() == Reloc::Static &&
818 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
819 StringRef Sym(".constructors_used");
820 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
826 if (GV->getName() == "llvm.global_dtors") {
827 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection());
828 EmitAlignment(Align, 0);
829 EmitXXStructorList(GV->getInitializer());
831 if (TM.getRelocationModel() == Reloc::Static &&
832 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
833 StringRef Sym(".destructors_used");
834 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
843 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
844 /// global in the specified llvm.used list for which emitUsedDirectiveFor
845 /// is true, as being used with this directive.
846 void AsmPrinter::EmitLLVMUsedList(Constant *List) {
847 // Should be an array of 'i8*'.
848 ConstantArray *InitList = dyn_cast<ConstantArray>(List);
849 if (InitList == 0) return;
851 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
852 const GlobalValue *GV =
853 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
854 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
855 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip);
859 /// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the
860 /// function pointers, ignoring the init priority.
861 void AsmPrinter::EmitXXStructorList(Constant *List) {
862 // Should be an array of '{ int, void ()* }' structs. The first value is the
863 // init priority, which we ignore.
864 if (!isa<ConstantArray>(List)) return;
865 ConstantArray *InitList = cast<ConstantArray>(List);
866 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
867 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
868 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs.
870 if (CS->getOperand(1)->isNullValue())
871 return; // Found a null terminator, exit printing.
872 // Emit the function pointer.
873 EmitGlobalConstant(CS->getOperand(1));
877 //===--------------------------------------------------------------------===//
878 // Emission and print routines
881 /// EmitInt8 - Emit a byte directive and value.
883 void AsmPrinter::EmitInt8(int Value) const {
884 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/);
887 /// EmitInt16 - Emit a short directive and value.
889 void AsmPrinter::EmitInt16(int Value) const {
890 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/);
893 /// EmitInt32 - Emit a long directive and value.
895 void AsmPrinter::EmitInt32(int Value) const {
896 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/);
899 /// EmitInt64 - Emit a long long directive and value.
901 void AsmPrinter::EmitInt64(uint64_t Value) const {
902 OutStreamer.EmitIntValue(Value, 8, 0/*addrspace*/);
905 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
906 /// in bytes of the directive is specified by Size and Hi/Lo specify the
907 /// labels. This implicitly uses .set if it is available.
908 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
909 unsigned Size) const {
910 // Get the Hi-Lo expression.
912 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
913 MCSymbolRefExpr::Create(Lo, OutContext),
916 if (!MAI->hasSetDirective()) {
917 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/);
921 // Otherwise, emit with .set (aka assignment).
923 OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) +
924 "set" + Twine(SetCounter++));
925 OutStreamer.EmitAssignment(SetLabel, Diff);
926 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/);
930 //===----------------------------------------------------------------------===//
932 // EmitAlignment - Emit an alignment directive to the specified power of
933 // two boundary. For example, if you pass in 3 here, you will get an 8
934 // byte alignment. If a global value is specified, and if that global has
935 // an explicit alignment requested, it will unconditionally override the
936 // alignment request. However, if ForcedAlignBits is specified, this value
937 // has final say: the ultimate alignment will be the max of ForcedAlignBits
938 // and the alignment computed with NumBits and the global.
942 // if (GV && GV->hasalignment) Align = GV->getalignment();
943 // Align = std::max(Align, ForcedAlignBits);
945 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
946 unsigned ForcedAlignBits,
947 bool UseFillExpr) const {
948 if (GV && GV->getAlignment())
949 NumBits = Log2_32(GV->getAlignment());
950 NumBits = std::max(NumBits, ForcedAlignBits);
952 if (NumBits == 0) return; // No need to emit alignment.
954 if (getCurrentSection()->getKind().isText())
955 OutStreamer.EmitCodeAlignment(1 << NumBits);
957 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
960 /// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
962 static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) {
963 MCContext &Ctx = AP.OutContext;
965 if (CV->isNullValue() || isa<UndefValue>(CV))
966 return MCConstantExpr::Create(0, Ctx);
968 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
969 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
971 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
972 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx);
973 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
974 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
976 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
978 llvm_unreachable("Unknown constant value to lower!");
979 return MCConstantExpr::Create(0, Ctx);
982 switch (CE->getOpcode()) {
984 // If the code isn't optimized, there may be outstanding folding
985 // opportunities. Attempt to fold the expression using TargetData as a
986 // last resort before giving up.
988 ConstantFoldConstantExpression(CE, AP.TM.getTargetData()))
990 return LowerConstant(C, AP);
994 llvm_unreachable("FIXME: Don't support this constant expr");
995 case Instruction::GetElementPtr: {
996 const TargetData &TD = *AP.TM.getTargetData();
997 // Generate a symbolic expression for the byte address
998 const Constant *PtrVal = CE->getOperand(0);
999 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
1000 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0],
1003 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
1007 // Truncate/sext the offset to the pointer size.
1008 if (TD.getPointerSizeInBits() != 64) {
1009 int SExtAmount = 64-TD.getPointerSizeInBits();
1010 Offset = (Offset << SExtAmount) >> SExtAmount;
1013 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1017 case Instruction::Trunc:
1018 // We emit the value and depend on the assembler to truncate the generated
1019 // expression properly. This is important for differences between
1020 // blockaddress labels. Since the two labels are in the same function, it
1021 // is reasonable to treat their delta as a 32-bit value.
1023 case Instruction::BitCast:
1024 return LowerConstant(CE->getOperand(0), AP);
1026 case Instruction::IntToPtr: {
1027 const TargetData &TD = *AP.TM.getTargetData();
1028 // Handle casts to pointers by changing them into casts to the appropriate
1029 // integer type. This promotes constant folding and simplifies this code.
1030 Constant *Op = CE->getOperand(0);
1031 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
1033 return LowerConstant(Op, AP);
1036 case Instruction::PtrToInt: {
1037 const TargetData &TD = *AP.TM.getTargetData();
1038 // Support only foldable casts to/from pointers that can be eliminated by
1039 // changing the pointer to the appropriately sized integer type.
1040 Constant *Op = CE->getOperand(0);
1041 const Type *Ty = CE->getType();
1043 const MCExpr *OpExpr = LowerConstant(Op, AP);
1045 // We can emit the pointer value into this slot if the slot is an
1046 // integer slot equal to the size of the pointer.
1047 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
1050 // Otherwise the pointer is smaller than the resultant integer, mask off
1051 // the high bits so we are sure to get a proper truncation if the input is
1053 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
1054 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1055 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1058 // The MC library also has a right-shift operator, but it isn't consistently
1059 // signed or unsigned between different targets.
1060 case Instruction::Add:
1061 case Instruction::Sub:
1062 case Instruction::Mul:
1063 case Instruction::SDiv:
1064 case Instruction::SRem:
1065 case Instruction::Shl:
1066 case Instruction::And:
1067 case Instruction::Or:
1068 case Instruction::Xor: {
1069 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP);
1070 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP);
1071 switch (CE->getOpcode()) {
1072 default: llvm_unreachable("Unknown binary operator constant cast expr");
1073 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1074 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1075 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1076 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1077 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1078 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1079 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1080 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1081 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1087 static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
1089 if (AddrSpace != 0 || !CA->isString()) {
1090 // Not a string. Print the values in successive locations
1091 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1092 AP.EmitGlobalConstant(CA->getOperand(i), AddrSpace);
1096 // Otherwise, it can be emitted as .ascii.
1097 SmallVector<char, 128> TmpVec;
1098 TmpVec.reserve(CA->getNumOperands());
1099 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1100 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
1102 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace);
1105 static void EmitGlobalConstantVector(const ConstantVector *CV,
1106 unsigned AddrSpace, AsmPrinter &AP) {
1107 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1108 AP.EmitGlobalConstant(CV->getOperand(i), AddrSpace);
1111 static void EmitGlobalConstantStruct(const ConstantStruct *CS,
1112 unsigned AddrSpace, AsmPrinter &AP) {
1113 // Print the fields in successive locations. Pad to align if needed!
1114 const TargetData *TD = AP.TM.getTargetData();
1115 unsigned Size = TD->getTypeAllocSize(CS->getType());
1116 const StructLayout *Layout = TD->getStructLayout(CS->getType());
1117 uint64_t SizeSoFar = 0;
1118 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1119 const Constant *Field = CS->getOperand(i);
1121 // Check if padding is needed and insert one or more 0s.
1122 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
1123 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1124 - Layout->getElementOffset(i)) - FieldSize;
1125 SizeSoFar += FieldSize + PadSize;
1127 // Now print the actual field value.
1128 AP.EmitGlobalConstant(Field, AddrSpace);
1130 // Insert padding - this may include padding to increase the size of the
1131 // current field up to the ABI size (if the struct is not packed) as well
1132 // as padding to ensure that the next field starts at the right offset.
1133 AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
1135 assert(SizeSoFar == Layout->getSizeInBytes() &&
1136 "Layout of constant struct may be incorrect!");
1139 static void EmitGlobalConstantUnion(const ConstantUnion *CU,
1140 unsigned AddrSpace, AsmPrinter &AP) {
1141 const TargetData *TD = AP.TM.getTargetData();
1142 unsigned Size = TD->getTypeAllocSize(CU->getType());
1144 const Constant *Contents = CU->getOperand(0);
1145 unsigned FilledSize = TD->getTypeAllocSize(Contents->getType());
1147 // Print the actually filled part
1148 AP.EmitGlobalConstant(Contents, AddrSpace);
1150 // And pad with enough zeroes
1151 AP.OutStreamer.EmitZeros(Size-FilledSize, AddrSpace);
1154 static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
1156 // FP Constants are printed as integer constants to avoid losing
1158 if (CFP->getType()->isDoubleTy()) {
1159 if (AP.VerboseAsm) {
1160 double Val = CFP->getValueAPF().convertToDouble();
1161 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n';
1164 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1165 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1169 if (CFP->getType()->isFloatTy()) {
1170 if (AP.VerboseAsm) {
1171 float Val = CFP->getValueAPF().convertToFloat();
1172 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n';
1174 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1175 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace);
1179 if (CFP->getType()->isX86_FP80Ty()) {
1180 // all long double variants are printed as hex
1181 // api needed to prevent premature destruction
1182 APInt API = CFP->getValueAPF().bitcastToAPInt();
1183 const uint64_t *p = API.getRawData();
1184 if (AP.VerboseAsm) {
1185 // Convert to double so we can print the approximate val as a comment.
1186 APFloat DoubleVal = CFP->getValueAPF();
1188 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1190 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= "
1191 << DoubleVal.convertToDouble() << '\n';
1194 if (AP.TM.getTargetData()->isBigEndian()) {
1195 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1196 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1198 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1199 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1202 // Emit the tail padding for the long double.
1203 const TargetData &TD = *AP.TM.getTargetData();
1204 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
1205 TD.getTypeStoreSize(CFP->getType()), AddrSpace);
1209 assert(CFP->getType()->isPPC_FP128Ty() &&
1210 "Floating point constant type not handled");
1211 // All long double variants are printed as hex api needed to prevent
1212 // premature destruction.
1213 APInt API = CFP->getValueAPF().bitcastToAPInt();
1214 const uint64_t *p = API.getRawData();
1215 if (AP.TM.getTargetData()->isBigEndian()) {
1216 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1217 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1219 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1220 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1224 static void EmitGlobalConstantLargeInt(const ConstantInt *CI,
1225 unsigned AddrSpace, AsmPrinter &AP) {
1226 const TargetData *TD = AP.TM.getTargetData();
1227 unsigned BitWidth = CI->getBitWidth();
1228 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
1230 // We don't expect assemblers to support integer data directives
1231 // for more than 64 bits, so we emit the data in at most 64-bit
1232 // quantities at a time.
1233 const uint64_t *RawData = CI->getValue().getRawData();
1234 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1235 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1236 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1240 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1241 void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1242 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) {
1243 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1244 if (Size == 0) Size = 1; // An empty "_foo:" followed by a section is undef.
1245 return OutStreamer.EmitZeros(Size, AddrSpace);
1248 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1249 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1256 OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue());
1257 OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1260 EmitGlobalConstantLargeInt(CI, AddrSpace, *this);
1265 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1266 return EmitGlobalConstantArray(CVA, AddrSpace, *this);
1268 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1269 return EmitGlobalConstantStruct(CVS, AddrSpace, *this);
1271 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1272 return EmitGlobalConstantFP(CFP, AddrSpace, *this);
1274 if (isa<ConstantPointerNull>(CV)) {
1275 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1276 OutStreamer.EmitIntValue(0, Size, AddrSpace);
1280 if (const ConstantUnion *CVU = dyn_cast<ConstantUnion>(CV))
1281 return EmitGlobalConstantUnion(CVU, AddrSpace, *this);
1283 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1284 return EmitGlobalConstantVector(V, AddrSpace, *this);
1286 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1287 // thread the streamer with EmitValue.
1288 OutStreamer.EmitValue(LowerConstant(CV, *this),
1289 TM.getTargetData()->getTypeAllocSize(CV->getType()),
1293 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1294 // Target doesn't support this yet!
1295 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1298 /// PrintSpecial - Print information related to the specified machine instr
1299 /// that is independent of the operand, and may be independent of the instr
1300 /// itself. This can be useful for portably encoding the comment character
1301 /// or other bits of target-specific knowledge into the asmstrings. The
1302 /// syntax used is ${:comment}. Targets can override this to add support
1303 /// for their own strange codes.
1304 void AsmPrinter::PrintSpecial(const MachineInstr *MI, const char *Code) const {
1305 if (!strcmp(Code, "private")) {
1306 O << MAI->getPrivateGlobalPrefix();
1307 } else if (!strcmp(Code, "comment")) {
1309 O << MAI->getCommentString();
1310 } else if (!strcmp(Code, "uid")) {
1311 // Comparing the address of MI isn't sufficient, because machineinstrs may
1312 // be allocated to the same address across functions.
1313 const Function *ThisF = MI->getParent()->getParent()->getFunction();
1315 // If this is a new LastFn instruction, bump the counter.
1316 if (LastMI != MI || LastFn != ThisF) {
1324 raw_string_ostream Msg(msg);
1325 Msg << "Unknown special formatter '" << Code
1326 << "' for machine instr: " << *MI;
1327 llvm_report_error(Msg.str());
1331 /// processDebugLoc - Processes the debug information of each machine
1332 /// instruction's DebugLoc.
1333 void AsmPrinter::processDebugLoc(const MachineInstr *MI,
1334 bool BeforePrintingInsn) {
1335 if (!MAI || !DW || !MAI->doesSupportDebugInformation()
1336 || !DW->ShouldEmitDwarfDebug())
1339 if (!BeforePrintingInsn)
1340 // After printing instruction
1347 /// printInlineAsm - This method formats and prints the specified machine
1348 /// instruction that is an inline asm.
1349 void AsmPrinter::printInlineAsm(const MachineInstr *MI) const {
1350 unsigned NumOperands = MI->getNumOperands();
1352 // Count the number of register definitions.
1353 unsigned NumDefs = 0;
1354 for (; MI->getOperand(NumDefs).isReg() && MI->getOperand(NumDefs).isDef();
1356 assert(NumDefs != NumOperands-1 && "No asm string?");
1358 assert(MI->getOperand(NumDefs).isSymbol() && "No asm string?");
1360 // Disassemble the AsmStr, printing out the literal pieces, the operands, etc.
1361 const char *AsmStr = MI->getOperand(NumDefs).getSymbolName();
1365 // If this asmstr is empty, just print the #APP/#NOAPP markers.
1366 // These are useful to see where empty asm's wound up.
1367 if (AsmStr[0] == 0) {
1368 O << MAI->getCommentString() << MAI->getInlineAsmStart() << "\n\t";
1369 O << MAI->getCommentString() << MAI->getInlineAsmEnd() << '\n';
1373 O << MAI->getCommentString() << MAI->getInlineAsmStart() << "\n\t";
1375 // The variant of the current asmprinter.
1376 int AsmPrinterVariant = MAI->getAssemblerDialect();
1378 int CurVariant = -1; // The number of the {.|.|.} region we are in.
1379 const char *LastEmitted = AsmStr; // One past the last character emitted.
1381 while (*LastEmitted) {
1382 switch (*LastEmitted) {
1384 // Not a special case, emit the string section literally.
1385 const char *LiteralEnd = LastEmitted+1;
1386 while (*LiteralEnd && *LiteralEnd != '{' && *LiteralEnd != '|' &&
1387 *LiteralEnd != '}' && *LiteralEnd != '$' && *LiteralEnd != '\n')
1389 if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1390 O.write(LastEmitted, LiteralEnd-LastEmitted);
1391 LastEmitted = LiteralEnd;
1395 ++LastEmitted; // Consume newline character.
1396 O << '\n'; // Indent code with newline.
1399 ++LastEmitted; // Consume '$' character.
1403 switch (*LastEmitted) {
1404 default: Done = false; break;
1405 case '$': // $$ -> $
1406 if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1408 ++LastEmitted; // Consume second '$' character.
1410 case '(': // $( -> same as GCC's { character.
1411 ++LastEmitted; // Consume '(' character.
1412 if (CurVariant != -1) {
1413 llvm_report_error("Nested variants found in inline asm string: '"
1414 + std::string(AsmStr) + "'");
1416 CurVariant = 0; // We're in the first variant now.
1419 ++LastEmitted; // consume '|' character.
1420 if (CurVariant == -1)
1421 O << '|'; // this is gcc's behavior for | outside a variant
1423 ++CurVariant; // We're in the next variant.
1425 case ')': // $) -> same as GCC's } char.
1426 ++LastEmitted; // consume ')' character.
1427 if (CurVariant == -1)
1428 O << '}'; // this is gcc's behavior for } outside a variant
1435 bool HasCurlyBraces = false;
1436 if (*LastEmitted == '{') { // ${variable}
1437 ++LastEmitted; // Consume '{' character.
1438 HasCurlyBraces = true;
1441 // If we have ${:foo}, then this is not a real operand reference, it is a
1442 // "magic" string reference, just like in .td files. Arrange to call
1444 if (HasCurlyBraces && *LastEmitted == ':') {
1446 const char *StrStart = LastEmitted;
1447 const char *StrEnd = strchr(StrStart, '}');
1449 llvm_report_error("Unterminated ${:foo} operand in inline asm string: '"
1450 + std::string(AsmStr) + "'");
1453 std::string Val(StrStart, StrEnd);
1454 PrintSpecial(MI, Val.c_str());
1455 LastEmitted = StrEnd+1;
1459 const char *IDStart = LastEmitted;
1462 long Val = strtol(IDStart, &IDEnd, 10); // We only accept numbers for IDs.
1463 if (!isdigit(*IDStart) || (Val == 0 && errno == EINVAL)) {
1464 llvm_report_error("Bad $ operand number in inline asm string: '"
1465 + std::string(AsmStr) + "'");
1467 LastEmitted = IDEnd;
1469 char Modifier[2] = { 0, 0 };
1471 if (HasCurlyBraces) {
1472 // If we have curly braces, check for a modifier character. This
1473 // supports syntax like ${0:u}, which correspond to "%u0" in GCC asm.
1474 if (*LastEmitted == ':') {
1475 ++LastEmitted; // Consume ':' character.
1476 if (*LastEmitted == 0) {
1477 llvm_report_error("Bad ${:} expression in inline asm string: '"
1478 + std::string(AsmStr) + "'");
1481 Modifier[0] = *LastEmitted;
1482 ++LastEmitted; // Consume modifier character.
1485 if (*LastEmitted != '}') {
1486 llvm_report_error("Bad ${} expression in inline asm string: '"
1487 + std::string(AsmStr) + "'");
1489 ++LastEmitted; // Consume '}' character.
1492 if ((unsigned)Val >= NumOperands-1) {
1493 llvm_report_error("Invalid $ operand number in inline asm string: '"
1494 + std::string(AsmStr) + "'");
1497 // Okay, we finally have a value number. Ask the target to print this
1499 if (CurVariant == -1 || CurVariant == AsmPrinterVariant) {
1504 // Scan to find the machine operand number for the operand.
1505 for (; Val; --Val) {
1506 if (OpNo >= MI->getNumOperands()) break;
1507 unsigned OpFlags = MI->getOperand(OpNo).getImm();
1508 OpNo += InlineAsm::getNumOperandRegisters(OpFlags) + 1;
1511 if (OpNo >= MI->getNumOperands()) {
1514 unsigned OpFlags = MI->getOperand(OpNo).getImm();
1515 ++OpNo; // Skip over the ID number.
1517 if (Modifier[0] == 'l') // labels are target independent
1518 O << *MI->getOperand(OpNo).getMBB()->getSymbol();
1520 AsmPrinter *AP = const_cast<AsmPrinter*>(this);
1521 if ((OpFlags & 7) == 4) {
1522 Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant,
1523 Modifier[0] ? Modifier : 0);
1525 Error = AP->PrintAsmOperand(MI, OpNo, AsmPrinterVariant,
1526 Modifier[0] ? Modifier : 0);
1532 raw_string_ostream Msg(msg);
1533 Msg << "Invalid operand found in inline asm: '" << AsmStr << "'\n";
1535 llvm_report_error(Msg.str());
1542 O << "\n\t" << MAI->getCommentString() << MAI->getInlineAsmEnd();
1543 OutStreamer.AddBlankLine();
1546 /// printImplicitDef - This method prints the specified machine instruction
1547 /// that is an implicit def.
1548 void AsmPrinter::printImplicitDef(const MachineInstr *MI) const {
1549 if (!VerboseAsm) return;
1550 O.PadToColumn(MAI->getCommentColumn());
1551 O << MAI->getCommentString() << " implicit-def: "
1552 << TRI->getName(MI->getOperand(0).getReg());
1553 OutStreamer.AddBlankLine();
1556 void AsmPrinter::printKill(const MachineInstr *MI) const {
1557 if (!VerboseAsm) return;
1558 O.PadToColumn(MAI->getCommentColumn());
1559 O << MAI->getCommentString() << " kill:";
1560 for (unsigned n = 0, e = MI->getNumOperands(); n != e; ++n) {
1561 const MachineOperand &op = MI->getOperand(n);
1562 assert(op.isReg() && "KILL instruction must have only register operands");
1563 O << ' ' << TRI->getName(op.getReg()) << (op.isDef() ? "<def>" : "<kill>");
1565 OutStreamer.AddBlankLine();
1568 /// printLabel - This method prints a local label used by debug and
1569 /// exception handling tables.
1570 void AsmPrinter::printLabelInst(const MachineInstr *MI) const {
1571 OutStreamer.EmitLabel(MI->getOperand(0).getMCSymbol());
1574 /// PrintAsmOperand - Print the specified operand of MI, an INLINEASM
1575 /// instruction, using the specified assembler variant. Targets should
1576 /// override this to format as appropriate.
1577 bool AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
1578 unsigned AsmVariant, const char *ExtraCode) {
1579 // Target doesn't support this yet!
1583 bool AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
1584 unsigned AsmVariant,
1585 const char *ExtraCode) {
1586 // Target doesn't support this yet!
1590 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
1591 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
1594 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
1595 return MMI->getAddrLabelSymbol(BB);
1598 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1599 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1600 return OutContext.GetOrCreateSymbol
1601 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
1602 + "_" + Twine(CPID));
1605 /// GetJTISymbol - Return the symbol for the specified jump table entry.
1606 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1607 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
1610 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
1611 /// FIXME: privatize to AsmPrinter.
1612 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
1613 return OutContext.GetOrCreateSymbol
1614 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
1615 Twine(UID) + "_set_" + Twine(MBBID));
1618 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1619 /// global value name as its base, with the specified suffix, and where the
1620 /// symbol is forced to have private linkage if ForcePrivate is true.
1621 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1623 bool ForcePrivate) const {
1624 SmallString<60> NameStr;
1625 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1626 NameStr.append(Suffix.begin(), Suffix.end());
1627 return OutContext.GetOrCreateSymbol(NameStr.str());
1630 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
1632 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
1633 SmallString<60> NameStr;
1634 Mang->getNameWithPrefix(NameStr, Sym);
1635 return OutContext.GetOrCreateSymbol(NameStr.str());
1640 /// PrintParentLoopComment - Print comments about parent loops of this one.
1641 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1642 unsigned FunctionNumber) {
1643 if (Loop == 0) return;
1644 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
1645 OS.indent(Loop->getLoopDepth()*2)
1646 << "Parent Loop BB" << FunctionNumber << "_"
1647 << Loop->getHeader()->getNumber()
1648 << " Depth=" << Loop->getLoopDepth() << '\n';
1652 /// PrintChildLoopComment - Print comments about child loops within
1653 /// the loop for this basic block, with nesting.
1654 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1655 unsigned FunctionNumber) {
1656 // Add child loop information
1657 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
1658 OS.indent((*CL)->getLoopDepth()*2)
1659 << "Child Loop BB" << FunctionNumber << "_"
1660 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
1662 PrintChildLoopComment(OS, *CL, FunctionNumber);
1666 /// PrintBasicBlockLoopComments - Pretty-print comments for basic blocks.
1667 static void PrintBasicBlockLoopComments(const MachineBasicBlock &MBB,
1668 const MachineLoopInfo *LI,
1669 const AsmPrinter &AP) {
1670 // Add loop depth information
1671 const MachineLoop *Loop = LI->getLoopFor(&MBB);
1672 if (Loop == 0) return;
1674 MachineBasicBlock *Header = Loop->getHeader();
1675 assert(Header && "No header for loop");
1677 // If this block is not a loop header, just print out what is the loop header
1679 if (Header != &MBB) {
1680 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
1681 Twine(AP.getFunctionNumber())+"_" +
1682 Twine(Loop->getHeader()->getNumber())+
1683 " Depth="+Twine(Loop->getLoopDepth()));
1687 // Otherwise, it is a loop header. Print out information about child and
1689 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
1691 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
1694 OS.indent(Loop->getLoopDepth()*2-2);
1699 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
1701 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
1705 /// EmitBasicBlockStart - This method prints the label for the specified
1706 /// MachineBasicBlock, an alignment (if present) and a comment describing
1707 /// it if appropriate.
1708 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
1709 // Emit an alignment directive for this block, if needed.
1710 if (unsigned Align = MBB->getAlignment())
1711 EmitAlignment(Log2_32(Align));
1713 // If the block has its address taken, emit any labels that were used to
1714 // reference the block. It is possible that there is more than one label
1715 // here, because multiple LLVM BB's may have been RAUW'd to this block after
1716 // the references were generated.
1717 if (MBB->hasAddressTaken()) {
1718 const BasicBlock *BB = MBB->getBasicBlock();
1720 OutStreamer.AddComment("Block address taken");
1722 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
1724 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
1725 OutStreamer.EmitLabel(Syms[i]);
1728 // Print the main label for the block.
1729 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
1731 // NOTE: Want this comment at start of line.
1732 O << MAI->getCommentString() << " BB#" << MBB->getNumber() << ':';
1733 if (const BasicBlock *BB = MBB->getBasicBlock())
1735 OutStreamer.AddComment("%" + BB->getName());
1737 PrintBasicBlockLoopComments(*MBB, LI, *this);
1738 OutStreamer.AddBlankLine();
1742 if (const BasicBlock *BB = MBB->getBasicBlock())
1744 OutStreamer.AddComment("%" + BB->getName());
1745 PrintBasicBlockLoopComments(*MBB, LI, *this);
1748 OutStreamer.EmitLabel(MBB->getSymbol());
1752 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility) const {
1753 MCSymbolAttr Attr = MCSA_Invalid;
1755 switch (Visibility) {
1757 case GlobalValue::HiddenVisibility:
1758 Attr = MAI->getHiddenVisibilityAttr();
1760 case GlobalValue::ProtectedVisibility:
1761 Attr = MAI->getProtectedVisibilityAttr();
1765 if (Attr != MCSA_Invalid)
1766 OutStreamer.EmitSymbolAttribute(Sym, Attr);
1769 void AsmPrinter::printOffset(int64_t Offset) const {
1772 else if (Offset < 0)
1776 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
1777 /// exactly one predecessor and the control transfer mechanism between
1778 /// the predecessor and this block is a fall-through.
1779 bool AsmPrinter::isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB)
1781 // If this is a landing pad, it isn't a fall through. If it has no preds,
1782 // then nothing falls through to it.
1783 if (MBB->isLandingPad() || MBB->pred_empty())
1786 // If there isn't exactly one predecessor, it can't be a fall through.
1787 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
1789 if (PI2 != MBB->pred_end())
1792 // The predecessor has to be immediately before this block.
1793 const MachineBasicBlock *Pred = *PI;
1795 if (!Pred->isLayoutSuccessor(MBB))
1798 // If the block is completely empty, then it definitely does fall through.
1802 // Otherwise, check the last instruction.
1803 const MachineInstr &LastInst = Pred->back();
1804 return !LastInst.getDesc().isBarrier();
1809 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1810 if (!S->usesMetadata())
1813 gcp_iterator GCPI = GCMetadataPrinters.find(S);
1814 if (GCPI != GCMetadataPrinters.end())
1815 return GCPI->second;
1817 const char *Name = S->getName().c_str();
1819 for (GCMetadataPrinterRegistry::iterator
1820 I = GCMetadataPrinterRegistry::begin(),
1821 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1822 if (strcmp(Name, I->getName()) == 0) {
1823 GCMetadataPrinter *GMP = I->instantiate();
1825 GCMetadataPrinters.insert(std::make_pair(S, GMP));
1829 llvm_report_error("no GCMetadataPrinter registered for GC: " + Twine(Name));