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), PrevDLT(NULL) {
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 // Add some workaround for linkonce linkage on Cygwin\MinGW.
311 if (MAI->getLinkOnceDirective() != 0 &&
312 (F->hasLinkOnceLinkage() || F->hasWeakLinkage()))
313 // FIXME: What is this?
314 O << "Lllvm$workaround$fake$stub$" << *CurrentFnSym << ":\n";
316 // Emit pre-function debug and/or EH information.
317 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
318 DW->BeginFunction(MF);
321 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
322 /// function. This can be overridden by targets as required to do custom stuff.
323 void AsmPrinter::EmitFunctionEntryLabel() {
324 OutStreamer.EmitLabel(CurrentFnSym);
328 /// EmitComments - Pretty-print comments for instructions.
329 static void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
330 const MachineFunction *MF = MI.getParent()->getParent();
331 const TargetMachine &TM = MF->getTarget();
333 if (!MI.getDebugLoc().isUnknown()) {
334 DILocation DLT = MF->getDILocation(MI.getDebugLoc());
336 // Print source line info.
337 DIScope Scope = DLT.getScope();
338 // Omit the directory, because it's likely to be long and uninteresting.
340 CommentOS << Scope.getFilename();
342 CommentOS << "<unknown>";
343 CommentOS << ':' << DLT.getLineNumber();
344 if (DLT.getColumnNumber() != 0)
345 CommentOS << ':' << DLT.getColumnNumber();
349 // Check for spills and reloads
352 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
354 // We assume a single instruction only has a spill or reload, not
356 const MachineMemOperand *MMO;
357 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
358 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
359 MMO = *MI.memoperands_begin();
360 CommentOS << MMO->getSize() << "-byte Reload\n";
362 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
363 if (FrameInfo->isSpillSlotObjectIndex(FI))
364 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
365 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
366 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
367 MMO = *MI.memoperands_begin();
368 CommentOS << MMO->getSize() << "-byte Spill\n";
370 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
371 if (FrameInfo->isSpillSlotObjectIndex(FI))
372 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
375 // Check for spill-induced copies
376 unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
377 if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg,
378 SrcSubIdx, DstSubIdx)) {
379 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
380 CommentOS << " Reload Reuse\n";
386 /// EmitFunctionBody - This method emits the body and trailer for a
388 void AsmPrinter::EmitFunctionBody() {
389 // Emit target-specific gunk before the function body.
390 EmitFunctionBodyStart();
392 // Print out code for the function.
393 bool HasAnyRealCode = false;
394 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
396 // Print a label for the basic block.
397 EmitBasicBlockStart(I);
398 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
400 // Print the assembly for the instruction.
402 HasAnyRealCode = true;
406 // FIXME: Clean up processDebugLoc.
407 processDebugLoc(II, true);
410 EmitComments(*II, OutStreamer.GetCommentOS());
412 switch (II->getOpcode()) {
413 case TargetOpcode::DBG_LABEL:
414 case TargetOpcode::EH_LABEL:
415 case TargetOpcode::GC_LABEL:
418 case TargetOpcode::INLINEASM:
421 case TargetOpcode::IMPLICIT_DEF:
422 printImplicitDef(II);
424 case TargetOpcode::KILL:
432 // FIXME: Clean up processDebugLoc.
433 processDebugLoc(II, false);
437 // If the function is empty and the object file uses .subsections_via_symbols,
438 // then we need to emit *something* to the function body to prevent the
439 // labels from collapsing together. Just emit a 0 byte.
440 if (MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)
441 OutStreamer.EmitIntValue(0, 1, 0/*addrspace*/);
443 // Emit target-specific gunk after the function body.
444 EmitFunctionBodyEnd();
446 if (MAI->hasDotTypeDotSizeDirective())
447 O << "\t.size\t" << *CurrentFnSym << ", .-" << *CurrentFnSym << '\n';
449 // Emit post-function debug information.
450 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
453 // Print out jump tables referenced by the function.
456 OutStreamer.AddBlankLine();
460 bool AsmPrinter::doFinalization(Module &M) {
461 // Emit global variables.
462 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
464 EmitGlobalVariable(I);
466 // Emit final debug information.
467 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
470 // If the target wants to know about weak references, print them all.
471 if (MAI->getWeakRefDirective()) {
472 // FIXME: This is not lazy, it would be nice to only print weak references
473 // to stuff that is actually used. Note that doing so would require targets
474 // to notice uses in operands (due to constant exprs etc). This should
475 // happen with the MC stuff eventually.
477 // Print out module-level global variables here.
478 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
480 if (!I->hasExternalWeakLinkage()) continue;
481 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
484 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
485 if (!I->hasExternalWeakLinkage()) continue;
486 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
490 if (MAI->hasSetDirective()) {
491 OutStreamer.AddBlankLine();
492 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
494 MCSymbol *Name = Mang->getSymbol(I);
496 const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
497 MCSymbol *Target = Mang->getSymbol(GV);
499 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
500 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
501 else if (I->hasWeakLinkage())
502 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
504 assert(I->hasLocalLinkage() && "Invalid alias linkage");
506 EmitVisibility(Name, I->getVisibility());
508 // Emit the directives as assignments aka .set:
509 OutStreamer.EmitAssignment(Name,
510 MCSymbolRefExpr::Create(Target, OutContext));
514 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
515 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
516 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
517 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
518 MP->finishAssembly(O, *this, *MAI);
520 // If we don't have any trampolines, then we don't require stack memory
521 // to be executable. Some targets have a directive to declare this.
522 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
523 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
524 if (MCSection *S = MAI->getNonexecutableStackSection(OutContext))
525 OutStreamer.SwitchSection(S);
527 // Allow the target to emit any magic that it wants at the end of the file,
528 // after everything else has gone out.
531 delete Mang; Mang = 0;
534 OutStreamer.Finish();
538 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
540 // Get the function symbol.
541 CurrentFnSym = Mang->getSymbol(MF.getFunction());
544 LI = &getAnalysis<MachineLoopInfo>();
548 // SectionCPs - Keep track the alignment, constpool entries per Section.
552 SmallVector<unsigned, 4> CPEs;
553 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
557 /// EmitConstantPool - Print to the current output stream assembly
558 /// representations of the constants in the constant pool MCP. This is
559 /// used to print out constants which have been "spilled to memory" by
560 /// the code generator.
562 void AsmPrinter::EmitConstantPool() {
563 const MachineConstantPool *MCP = MF->getConstantPool();
564 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
565 if (CP.empty()) return;
567 // Calculate sections for constant pool entries. We collect entries to go into
568 // the same section together to reduce amount of section switch statements.
569 SmallVector<SectionCPs, 4> CPSections;
570 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
571 const MachineConstantPoolEntry &CPE = CP[i];
572 unsigned Align = CPE.getAlignment();
575 switch (CPE.getRelocationInfo()) {
576 default: llvm_unreachable("Unknown section kind");
577 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
579 Kind = SectionKind::getReadOnlyWithRelLocal();
582 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
583 case 4: Kind = SectionKind::getMergeableConst4(); break;
584 case 8: Kind = SectionKind::getMergeableConst8(); break;
585 case 16: Kind = SectionKind::getMergeableConst16();break;
586 default: Kind = SectionKind::getMergeableConst(); break;
590 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
592 // The number of sections are small, just do a linear search from the
593 // last section to the first.
595 unsigned SecIdx = CPSections.size();
596 while (SecIdx != 0) {
597 if (CPSections[--SecIdx].S == S) {
603 SecIdx = CPSections.size();
604 CPSections.push_back(SectionCPs(S, Align));
607 if (Align > CPSections[SecIdx].Alignment)
608 CPSections[SecIdx].Alignment = Align;
609 CPSections[SecIdx].CPEs.push_back(i);
612 // Now print stuff into the calculated sections.
613 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
614 OutStreamer.SwitchSection(CPSections[i].S);
615 EmitAlignment(Log2_32(CPSections[i].Alignment));
618 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
619 unsigned CPI = CPSections[i].CPEs[j];
620 MachineConstantPoolEntry CPE = CP[CPI];
622 // Emit inter-object padding for alignment.
623 unsigned AlignMask = CPE.getAlignment() - 1;
624 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
625 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/);
627 const Type *Ty = CPE.getType();
628 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
630 // Emit the label with a comment on it.
632 OutStreamer.GetCommentOS() << "constant pool ";
633 WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(),
634 MF->getFunction()->getParent());
635 OutStreamer.GetCommentOS() << '\n';
637 OutStreamer.EmitLabel(GetCPISymbol(CPI));
639 if (CPE.isMachineConstantPoolEntry())
640 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
642 EmitGlobalConstant(CPE.Val.ConstVal);
647 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
648 /// by the current function to the current output stream.
650 void AsmPrinter::EmitJumpTableInfo() {
651 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
652 if (MJTI == 0) return;
653 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
654 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
655 if (JT.empty()) return;
657 // Pick the directive to use to print the jump table entries, and switch to
658 // the appropriate section.
659 const Function *F = MF->getFunction();
660 bool JTInDiffSection = false;
661 if (// In PIC mode, we need to emit the jump table to the same section as the
662 // function body itself, otherwise the label differences won't make sense.
663 // FIXME: Need a better predicate for this: what about custom entries?
664 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
665 // We should also do if the section name is NULL or function is declared
666 // in discardable section
667 // FIXME: this isn't the right predicate, should be based on the MCSection
669 F->isWeakForLinker()) {
670 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
672 // Otherwise, drop it in the readonly section.
673 const MCSection *ReadOnlySection =
674 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
675 OutStreamer.SwitchSection(ReadOnlySection);
676 JTInDiffSection = true;
679 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData())));
681 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
682 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
684 // If this jump table was deleted, ignore it.
685 if (JTBBs.empty()) continue;
687 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
688 // .set directive for each unique entry. This reduces the number of
689 // relocations the assembler will generate for the jump table.
690 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
691 MAI->hasSetDirective()) {
692 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
693 const TargetLowering *TLI = TM.getTargetLowering();
694 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
695 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
696 const MachineBasicBlock *MBB = JTBBs[ii];
697 if (!EmittedSets.insert(MBB)) continue;
699 // .set LJTSet, LBB32-base
701 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
702 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
703 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
707 // On some targets (e.g. Darwin) we want to emit two consequtive labels
708 // before each jump table. The first label is never referenced, but tells
709 // the assembler and linker the extents of the jump table object. The
710 // second label is actually referenced by the code.
711 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
712 // FIXME: This doesn't have to have any specific name, just any randomly
713 // named and numbered 'l' label would work. Simplify GetJTISymbol.
714 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
716 OutStreamer.EmitLabel(GetJTISymbol(JTI));
718 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
719 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
723 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
725 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
726 const MachineBasicBlock *MBB,
727 unsigned UID) const {
728 const MCExpr *Value = 0;
729 switch (MJTI->getEntryKind()) {
730 case MachineJumpTableInfo::EK_Inline:
731 llvm_unreachable("Cannot emit EK_Inline jump table entry"); break;
732 case MachineJumpTableInfo::EK_Custom32:
733 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
736 case MachineJumpTableInfo::EK_BlockAddress:
737 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
739 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
741 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
742 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
743 // with a relocation as gp-relative, e.g.:
745 MCSymbol *MBBSym = MBB->getSymbol();
746 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
750 case MachineJumpTableInfo::EK_LabelDifference32: {
751 // EK_LabelDifference32 - Each entry is the address of the block minus
752 // the address of the jump table. This is used for PIC jump tables where
753 // gprel32 is not supported. e.g.:
754 // .word LBB123 - LJTI1_2
755 // If the .set directive is supported, this is emitted as:
756 // .set L4_5_set_123, LBB123 - LJTI1_2
757 // .word L4_5_set_123
759 // If we have emitted set directives for the jump table entries, print
760 // them rather than the entries themselves. If we're emitting PIC, then
761 // emit the table entries as differences between two text section labels.
762 if (MAI->hasSetDirective()) {
763 // If we used .set, reference the .set's symbol.
764 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
768 // Otherwise, use the difference as the jump table entry.
769 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
770 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
771 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
776 assert(Value && "Unknown entry kind!");
778 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData());
779 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0);
783 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
784 /// special global used by LLVM. If so, emit it and return true, otherwise
785 /// do nothing and return false.
786 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
787 if (GV->getName() == "llvm.used") {
788 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
789 EmitLLVMUsedList(GV->getInitializer());
793 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
794 if (GV->getSection() == "llvm.metadata" ||
795 GV->hasAvailableExternallyLinkage())
798 if (!GV->hasAppendingLinkage()) return false;
800 assert(GV->hasInitializer() && "Not a special LLVM global!");
802 const TargetData *TD = TM.getTargetData();
803 unsigned Align = Log2_32(TD->getPointerPrefAlignment());
804 if (GV->getName() == "llvm.global_ctors") {
805 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection());
806 EmitAlignment(Align, 0);
807 EmitXXStructorList(GV->getInitializer());
809 if (TM.getRelocationModel() == Reloc::Static &&
810 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
811 StringRef Sym(".constructors_used");
812 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
818 if (GV->getName() == "llvm.global_dtors") {
819 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection());
820 EmitAlignment(Align, 0);
821 EmitXXStructorList(GV->getInitializer());
823 if (TM.getRelocationModel() == Reloc::Static &&
824 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
825 StringRef Sym(".destructors_used");
826 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
835 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
836 /// global in the specified llvm.used list for which emitUsedDirectiveFor
837 /// is true, as being used with this directive.
838 void AsmPrinter::EmitLLVMUsedList(Constant *List) {
839 // Should be an array of 'i8*'.
840 ConstantArray *InitList = dyn_cast<ConstantArray>(List);
841 if (InitList == 0) return;
843 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
844 const GlobalValue *GV =
845 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
846 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
847 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip);
851 /// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the
852 /// function pointers, ignoring the init priority.
853 void AsmPrinter::EmitXXStructorList(Constant *List) {
854 // Should be an array of '{ int, void ()* }' structs. The first value is the
855 // init priority, which we ignore.
856 if (!isa<ConstantArray>(List)) return;
857 ConstantArray *InitList = cast<ConstantArray>(List);
858 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
859 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
860 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs.
862 if (CS->getOperand(1)->isNullValue())
863 return; // Found a null terminator, exit printing.
864 // Emit the function pointer.
865 EmitGlobalConstant(CS->getOperand(1));
869 //===--------------------------------------------------------------------===//
870 // Emission and print routines
873 /// EmitInt8 - Emit a byte directive and value.
875 void AsmPrinter::EmitInt8(int Value) const {
876 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/);
879 /// EmitInt16 - Emit a short directive and value.
881 void AsmPrinter::EmitInt16(int Value) const {
882 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/);
885 /// EmitInt32 - Emit a long directive and value.
887 void AsmPrinter::EmitInt32(int Value) const {
888 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/);
891 /// EmitInt64 - Emit a long long directive and value.
893 void AsmPrinter::EmitInt64(uint64_t Value) const {
894 OutStreamer.EmitIntValue(Value, 8, 0/*addrspace*/);
897 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
898 /// in bytes of the directive is specified by Size and Hi/Lo specify the
899 /// labels. This implicitly uses .set if it is available.
900 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
901 unsigned Size) const {
902 // Get the Hi-Lo expression.
904 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
905 MCSymbolRefExpr::Create(Lo, OutContext),
908 if (!MAI->hasSetDirective()) {
909 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/);
913 // Otherwise, emit with .set (aka assignment).
915 OutContext.GetOrCreateTemporarySymbol(Twine(MAI->getPrivateGlobalPrefix()) +
916 "set" + Twine(SetCounter++));
917 OutStreamer.EmitAssignment(SetLabel, Diff);
918 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/);
922 //===----------------------------------------------------------------------===//
924 // EmitAlignment - Emit an alignment directive to the specified power of
925 // two boundary. For example, if you pass in 3 here, you will get an 8
926 // byte alignment. If a global value is specified, and if that global has
927 // an explicit alignment requested, it will unconditionally override the
928 // alignment request. However, if ForcedAlignBits is specified, this value
929 // has final say: the ultimate alignment will be the max of ForcedAlignBits
930 // and the alignment computed with NumBits and the global.
934 // if (GV && GV->hasalignment) Align = GV->getalignment();
935 // Align = std::max(Align, ForcedAlignBits);
937 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
938 unsigned ForcedAlignBits,
939 bool UseFillExpr) const {
940 if (GV && GV->getAlignment())
941 NumBits = Log2_32(GV->getAlignment());
942 NumBits = std::max(NumBits, ForcedAlignBits);
944 if (NumBits == 0) return; // No need to emit alignment.
946 if (getCurrentSection()->getKind().isText())
947 OutStreamer.EmitCodeAlignment(1 << NumBits);
949 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
952 /// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
954 static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) {
955 MCContext &Ctx = AP.OutContext;
957 if (CV->isNullValue() || isa<UndefValue>(CV))
958 return MCConstantExpr::Create(0, Ctx);
960 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
961 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
963 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
964 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx);
965 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
966 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
968 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
970 llvm_unreachable("Unknown constant value to lower!");
971 return MCConstantExpr::Create(0, Ctx);
974 switch (CE->getOpcode()) {
976 // If the code isn't optimized, there may be outstanding folding
977 // opportunities. Attempt to fold the expression using TargetData as a
978 // last resort before giving up.
980 ConstantFoldConstantExpression(CE, AP.TM.getTargetData()))
982 return LowerConstant(C, AP);
986 llvm_unreachable("FIXME: Don't support this constant expr");
987 case Instruction::GetElementPtr: {
988 const TargetData &TD = *AP.TM.getTargetData();
989 // Generate a symbolic expression for the byte address
990 const Constant *PtrVal = CE->getOperand(0);
991 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
992 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0],
995 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
999 // Truncate/sext the offset to the pointer size.
1000 if (TD.getPointerSizeInBits() != 64) {
1001 int SExtAmount = 64-TD.getPointerSizeInBits();
1002 Offset = (Offset << SExtAmount) >> SExtAmount;
1005 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1009 case Instruction::Trunc:
1010 // We emit the value and depend on the assembler to truncate the generated
1011 // expression properly. This is important for differences between
1012 // blockaddress labels. Since the two labels are in the same function, it
1013 // is reasonable to treat their delta as a 32-bit value.
1015 case Instruction::BitCast:
1016 return LowerConstant(CE->getOperand(0), AP);
1018 case Instruction::IntToPtr: {
1019 const TargetData &TD = *AP.TM.getTargetData();
1020 // Handle casts to pointers by changing them into casts to the appropriate
1021 // integer type. This promotes constant folding and simplifies this code.
1022 Constant *Op = CE->getOperand(0);
1023 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
1025 return LowerConstant(Op, AP);
1028 case Instruction::PtrToInt: {
1029 const TargetData &TD = *AP.TM.getTargetData();
1030 // Support only foldable casts to/from pointers that can be eliminated by
1031 // changing the pointer to the appropriately sized integer type.
1032 Constant *Op = CE->getOperand(0);
1033 const Type *Ty = CE->getType();
1035 const MCExpr *OpExpr = LowerConstant(Op, AP);
1037 // We can emit the pointer value into this slot if the slot is an
1038 // integer slot equal to the size of the pointer.
1039 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
1042 // Otherwise the pointer is smaller than the resultant integer, mask off
1043 // the high bits so we are sure to get a proper truncation if the input is
1045 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
1046 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1047 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1050 // The MC library also has a right-shift operator, but it isn't consistently
1051 // signed or unsigned between different targets.
1052 case Instruction::Add:
1053 case Instruction::Sub:
1054 case Instruction::Mul:
1055 case Instruction::SDiv:
1056 case Instruction::SRem:
1057 case Instruction::Shl:
1058 case Instruction::And:
1059 case Instruction::Or:
1060 case Instruction::Xor: {
1061 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP);
1062 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP);
1063 switch (CE->getOpcode()) {
1064 default: llvm_unreachable("Unknown binary operator constant cast expr");
1065 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1066 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1067 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1068 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1069 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1070 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1071 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1072 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1073 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1079 static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
1081 if (AddrSpace != 0 || !CA->isString()) {
1082 // Not a string. Print the values in successive locations
1083 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1084 AP.EmitGlobalConstant(CA->getOperand(i), AddrSpace);
1088 // Otherwise, it can be emitted as .ascii.
1089 SmallVector<char, 128> TmpVec;
1090 TmpVec.reserve(CA->getNumOperands());
1091 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1092 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
1094 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace);
1097 static void EmitGlobalConstantVector(const ConstantVector *CV,
1098 unsigned AddrSpace, AsmPrinter &AP) {
1099 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1100 AP.EmitGlobalConstant(CV->getOperand(i), AddrSpace);
1103 static void EmitGlobalConstantStruct(const ConstantStruct *CS,
1104 unsigned AddrSpace, AsmPrinter &AP) {
1105 // Print the fields in successive locations. Pad to align if needed!
1106 const TargetData *TD = AP.TM.getTargetData();
1107 unsigned Size = TD->getTypeAllocSize(CS->getType());
1108 const StructLayout *Layout = TD->getStructLayout(CS->getType());
1109 uint64_t SizeSoFar = 0;
1110 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1111 const Constant *Field = CS->getOperand(i);
1113 // Check if padding is needed and insert one or more 0s.
1114 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
1115 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1116 - Layout->getElementOffset(i)) - FieldSize;
1117 SizeSoFar += FieldSize + PadSize;
1119 // Now print the actual field value.
1120 AP.EmitGlobalConstant(Field, AddrSpace);
1122 // Insert padding - this may include padding to increase the size of the
1123 // current field up to the ABI size (if the struct is not packed) as well
1124 // as padding to ensure that the next field starts at the right offset.
1125 AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
1127 assert(SizeSoFar == Layout->getSizeInBytes() &&
1128 "Layout of constant struct may be incorrect!");
1131 static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
1133 // FP Constants are printed as integer constants to avoid losing
1135 if (CFP->getType()->isDoubleTy()) {
1136 if (AP.VerboseAsm) {
1137 double Val = CFP->getValueAPF().convertToDouble();
1138 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n';
1141 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1142 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1146 if (CFP->getType()->isFloatTy()) {
1147 if (AP.VerboseAsm) {
1148 float Val = CFP->getValueAPF().convertToFloat();
1149 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n';
1151 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1152 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace);
1156 if (CFP->getType()->isX86_FP80Ty()) {
1157 // all long double variants are printed as hex
1158 // api needed to prevent premature destruction
1159 APInt API = CFP->getValueAPF().bitcastToAPInt();
1160 const uint64_t *p = API.getRawData();
1161 if (AP.VerboseAsm) {
1162 // Convert to double so we can print the approximate val as a comment.
1163 APFloat DoubleVal = CFP->getValueAPF();
1165 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1167 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= "
1168 << DoubleVal.convertToDouble() << '\n';
1171 if (AP.TM.getTargetData()->isBigEndian()) {
1172 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1173 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1175 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1176 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1179 // Emit the tail padding for the long double.
1180 const TargetData &TD = *AP.TM.getTargetData();
1181 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
1182 TD.getTypeStoreSize(CFP->getType()), AddrSpace);
1186 assert(CFP->getType()->isPPC_FP128Ty() &&
1187 "Floating point constant type not handled");
1188 // All long double variants are printed as hex api needed to prevent
1189 // premature destruction.
1190 APInt API = CFP->getValueAPF().bitcastToAPInt();
1191 const uint64_t *p = API.getRawData();
1192 if (AP.TM.getTargetData()->isBigEndian()) {
1193 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1194 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1196 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1197 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1201 static void EmitGlobalConstantLargeInt(const ConstantInt *CI,
1202 unsigned AddrSpace, AsmPrinter &AP) {
1203 const TargetData *TD = AP.TM.getTargetData();
1204 unsigned BitWidth = CI->getBitWidth();
1205 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
1207 // We don't expect assemblers to support integer data directives
1208 // for more than 64 bits, so we emit the data in at most 64-bit
1209 // quantities at a time.
1210 const uint64_t *RawData = CI->getValue().getRawData();
1211 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1212 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1213 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1217 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1218 void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1219 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) {
1220 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1221 if (Size == 0) Size = 1; // An empty "_foo:" followed by a section is undef.
1222 return OutStreamer.EmitZeros(Size, AddrSpace);
1225 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1226 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1233 OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue());
1234 OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1237 EmitGlobalConstantLargeInt(CI, AddrSpace, *this);
1242 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1243 return EmitGlobalConstantArray(CVA, AddrSpace, *this);
1245 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1246 return EmitGlobalConstantStruct(CVS, AddrSpace, *this);
1248 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1249 return EmitGlobalConstantFP(CFP, AddrSpace, *this);
1251 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1252 return EmitGlobalConstantVector(V, AddrSpace, *this);
1254 if (isa<ConstantPointerNull>(CV)) {
1255 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1256 OutStreamer.EmitIntValue(0, Size, AddrSpace);
1260 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1261 // thread the streamer with EmitValue.
1262 OutStreamer.EmitValue(LowerConstant(CV, *this),
1263 TM.getTargetData()->getTypeAllocSize(CV->getType()),
1267 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1268 // Target doesn't support this yet!
1269 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1272 /// PrintSpecial - Print information related to the specified machine instr
1273 /// that is independent of the operand, and may be independent of the instr
1274 /// itself. This can be useful for portably encoding the comment character
1275 /// or other bits of target-specific knowledge into the asmstrings. The
1276 /// syntax used is ${:comment}. Targets can override this to add support
1277 /// for their own strange codes.
1278 void AsmPrinter::PrintSpecial(const MachineInstr *MI, const char *Code) const {
1279 if (!strcmp(Code, "private")) {
1280 O << MAI->getPrivateGlobalPrefix();
1281 } else if (!strcmp(Code, "comment")) {
1283 O << MAI->getCommentString();
1284 } else if (!strcmp(Code, "uid")) {
1285 // Comparing the address of MI isn't sufficient, because machineinstrs may
1286 // be allocated to the same address across functions.
1287 const Function *ThisF = MI->getParent()->getParent()->getFunction();
1289 // If this is a new LastFn instruction, bump the counter.
1290 if (LastMI != MI || LastFn != ThisF) {
1298 raw_string_ostream Msg(msg);
1299 Msg << "Unknown special formatter '" << Code
1300 << "' for machine instr: " << *MI;
1301 llvm_report_error(Msg.str());
1305 /// processDebugLoc - Processes the debug information of each machine
1306 /// instruction's DebugLoc.
1307 void AsmPrinter::processDebugLoc(const MachineInstr *MI,
1308 bool BeforePrintingInsn) {
1309 if (!MAI || !DW || !MAI->doesSupportDebugInformation()
1310 || !DW->ShouldEmitDwarfDebug())
1312 DebugLoc DL = MI->getDebugLoc();
1315 DILocation CurDLT = MF->getDILocation(DL);
1316 if (!CurDLT.getScope().Verify())
1319 if (!BeforePrintingInsn) {
1320 // After printing instruction
1322 } else if (CurDLT.getNode() != PrevDLT) {
1323 MCSymbol *L = DW->RecordSourceLine(CurDLT.getLineNumber(),
1324 CurDLT.getColumnNumber(),
1325 CurDLT.getScope().getNode());
1326 DW->BeginScope(MI, L);
1327 PrevDLT = CurDLT.getNode();
1332 /// printInlineAsm - This method formats and prints the specified machine
1333 /// instruction that is an inline asm.
1334 void AsmPrinter::printInlineAsm(const MachineInstr *MI) const {
1335 unsigned NumOperands = MI->getNumOperands();
1337 // Count the number of register definitions.
1338 unsigned NumDefs = 0;
1339 for (; MI->getOperand(NumDefs).isReg() && MI->getOperand(NumDefs).isDef();
1341 assert(NumDefs != NumOperands-1 && "No asm string?");
1343 assert(MI->getOperand(NumDefs).isSymbol() && "No asm string?");
1345 // Disassemble the AsmStr, printing out the literal pieces, the operands, etc.
1346 const char *AsmStr = MI->getOperand(NumDefs).getSymbolName();
1350 // If this asmstr is empty, just print the #APP/#NOAPP markers.
1351 // These are useful to see where empty asm's wound up.
1352 if (AsmStr[0] == 0) {
1353 O << MAI->getCommentString() << MAI->getInlineAsmStart() << "\n\t";
1354 O << MAI->getCommentString() << MAI->getInlineAsmEnd() << '\n';
1358 O << MAI->getCommentString() << MAI->getInlineAsmStart() << "\n\t";
1360 // The variant of the current asmprinter.
1361 int AsmPrinterVariant = MAI->getAssemblerDialect();
1363 int CurVariant = -1; // The number of the {.|.|.} region we are in.
1364 const char *LastEmitted = AsmStr; // One past the last character emitted.
1366 while (*LastEmitted) {
1367 switch (*LastEmitted) {
1369 // Not a special case, emit the string section literally.
1370 const char *LiteralEnd = LastEmitted+1;
1371 while (*LiteralEnd && *LiteralEnd != '{' && *LiteralEnd != '|' &&
1372 *LiteralEnd != '}' && *LiteralEnd != '$' && *LiteralEnd != '\n')
1374 if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1375 O.write(LastEmitted, LiteralEnd-LastEmitted);
1376 LastEmitted = LiteralEnd;
1380 ++LastEmitted; // Consume newline character.
1381 O << '\n'; // Indent code with newline.
1384 ++LastEmitted; // Consume '$' character.
1388 switch (*LastEmitted) {
1389 default: Done = false; break;
1390 case '$': // $$ -> $
1391 if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1393 ++LastEmitted; // Consume second '$' character.
1395 case '(': // $( -> same as GCC's { character.
1396 ++LastEmitted; // Consume '(' character.
1397 if (CurVariant != -1) {
1398 llvm_report_error("Nested variants found in inline asm string: '"
1399 + std::string(AsmStr) + "'");
1401 CurVariant = 0; // We're in the first variant now.
1404 ++LastEmitted; // consume '|' character.
1405 if (CurVariant == -1)
1406 O << '|'; // this is gcc's behavior for | outside a variant
1408 ++CurVariant; // We're in the next variant.
1410 case ')': // $) -> same as GCC's } char.
1411 ++LastEmitted; // consume ')' character.
1412 if (CurVariant == -1)
1413 O << '}'; // this is gcc's behavior for } outside a variant
1420 bool HasCurlyBraces = false;
1421 if (*LastEmitted == '{') { // ${variable}
1422 ++LastEmitted; // Consume '{' character.
1423 HasCurlyBraces = true;
1426 // If we have ${:foo}, then this is not a real operand reference, it is a
1427 // "magic" string reference, just like in .td files. Arrange to call
1429 if (HasCurlyBraces && *LastEmitted == ':') {
1431 const char *StrStart = LastEmitted;
1432 const char *StrEnd = strchr(StrStart, '}');
1434 llvm_report_error("Unterminated ${:foo} operand in inline asm string: '"
1435 + std::string(AsmStr) + "'");
1438 std::string Val(StrStart, StrEnd);
1439 PrintSpecial(MI, Val.c_str());
1440 LastEmitted = StrEnd+1;
1444 const char *IDStart = LastEmitted;
1447 long Val = strtol(IDStart, &IDEnd, 10); // We only accept numbers for IDs.
1448 if (!isdigit(*IDStart) || (Val == 0 && errno == EINVAL)) {
1449 llvm_report_error("Bad $ operand number in inline asm string: '"
1450 + std::string(AsmStr) + "'");
1452 LastEmitted = IDEnd;
1454 char Modifier[2] = { 0, 0 };
1456 if (HasCurlyBraces) {
1457 // If we have curly braces, check for a modifier character. This
1458 // supports syntax like ${0:u}, which correspond to "%u0" in GCC asm.
1459 if (*LastEmitted == ':') {
1460 ++LastEmitted; // Consume ':' character.
1461 if (*LastEmitted == 0) {
1462 llvm_report_error("Bad ${:} expression in inline asm string: '"
1463 + std::string(AsmStr) + "'");
1466 Modifier[0] = *LastEmitted;
1467 ++LastEmitted; // Consume modifier character.
1470 if (*LastEmitted != '}') {
1471 llvm_report_error("Bad ${} expression in inline asm string: '"
1472 + std::string(AsmStr) + "'");
1474 ++LastEmitted; // Consume '}' character.
1477 if ((unsigned)Val >= NumOperands-1) {
1478 llvm_report_error("Invalid $ operand number in inline asm string: '"
1479 + std::string(AsmStr) + "'");
1482 // Okay, we finally have a value number. Ask the target to print this
1484 if (CurVariant == -1 || CurVariant == AsmPrinterVariant) {
1489 // Scan to find the machine operand number for the operand.
1490 for (; Val; --Val) {
1491 if (OpNo >= MI->getNumOperands()) break;
1492 unsigned OpFlags = MI->getOperand(OpNo).getImm();
1493 OpNo += InlineAsm::getNumOperandRegisters(OpFlags) + 1;
1496 if (OpNo >= MI->getNumOperands()) {
1499 unsigned OpFlags = MI->getOperand(OpNo).getImm();
1500 ++OpNo; // Skip over the ID number.
1502 if (Modifier[0] == 'l') // labels are target independent
1503 O << *MI->getOperand(OpNo).getMBB()->getSymbol();
1505 AsmPrinter *AP = const_cast<AsmPrinter*>(this);
1506 if ((OpFlags & 7) == 4) {
1507 Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant,
1508 Modifier[0] ? Modifier : 0);
1510 Error = AP->PrintAsmOperand(MI, OpNo, AsmPrinterVariant,
1511 Modifier[0] ? Modifier : 0);
1517 raw_string_ostream Msg(msg);
1518 Msg << "Invalid operand found in inline asm: '" << AsmStr << "'\n";
1520 llvm_report_error(Msg.str());
1527 O << "\n\t" << MAI->getCommentString() << MAI->getInlineAsmEnd();
1528 OutStreamer.AddBlankLine();
1531 /// printImplicitDef - This method prints the specified machine instruction
1532 /// that is an implicit def.
1533 void AsmPrinter::printImplicitDef(const MachineInstr *MI) const {
1534 if (!VerboseAsm) return;
1535 O.PadToColumn(MAI->getCommentColumn());
1536 O << MAI->getCommentString() << " implicit-def: "
1537 << TRI->getName(MI->getOperand(0).getReg());
1538 OutStreamer.AddBlankLine();
1541 void AsmPrinter::printKill(const MachineInstr *MI) const {
1542 if (!VerboseAsm) return;
1543 O.PadToColumn(MAI->getCommentColumn());
1544 O << MAI->getCommentString() << " kill:";
1545 for (unsigned n = 0, e = MI->getNumOperands(); n != e; ++n) {
1546 const MachineOperand &op = MI->getOperand(n);
1547 assert(op.isReg() && "KILL instruction must have only register operands");
1548 O << ' ' << TRI->getName(op.getReg()) << (op.isDef() ? "<def>" : "<kill>");
1550 OutStreamer.AddBlankLine();
1553 /// printLabel - This method prints a local label used by debug and
1554 /// exception handling tables.
1555 void AsmPrinter::printLabelInst(const MachineInstr *MI) const {
1556 OutStreamer.EmitLabel(MI->getOperand(0).getMCSymbol());
1559 /// PrintAsmOperand - Print the specified operand of MI, an INLINEASM
1560 /// instruction, using the specified assembler variant. Targets should
1561 /// override this to format as appropriate.
1562 bool AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
1563 unsigned AsmVariant, const char *ExtraCode) {
1564 // Target doesn't support this yet!
1568 bool AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
1569 unsigned AsmVariant,
1570 const char *ExtraCode) {
1571 // Target doesn't support this yet!
1575 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
1576 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
1579 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
1580 return MMI->getAddrLabelSymbol(BB);
1583 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1584 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1585 return OutContext.GetOrCreateTemporarySymbol
1586 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
1587 + "_" + Twine(CPID));
1590 /// GetJTISymbol - Return the symbol for the specified jump table entry.
1591 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1592 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
1595 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
1596 /// FIXME: privatize to AsmPrinter.
1597 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
1598 return OutContext.GetOrCreateTemporarySymbol
1599 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
1600 Twine(UID) + "_set_" + Twine(MBBID));
1603 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1604 /// global value name as its base, with the specified suffix, and where the
1605 /// symbol is forced to have private linkage if ForcePrivate is true.
1606 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1608 bool ForcePrivate) const {
1609 SmallString<60> NameStr;
1610 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1611 NameStr.append(Suffix.begin(), Suffix.end());
1612 if (!GV->hasPrivateLinkage() && !ForcePrivate)
1613 return OutContext.GetOrCreateSymbol(NameStr.str());
1614 return OutContext.GetOrCreateTemporarySymbol(NameStr.str());
1617 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
1619 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
1620 SmallString<60> NameStr;
1621 Mang->getNameWithPrefix(NameStr, Sym);
1622 return OutContext.GetOrCreateSymbol(NameStr.str());
1627 /// PrintParentLoopComment - Print comments about parent loops of this one.
1628 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1629 unsigned FunctionNumber) {
1630 if (Loop == 0) return;
1631 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
1632 OS.indent(Loop->getLoopDepth()*2)
1633 << "Parent Loop BB" << FunctionNumber << "_"
1634 << Loop->getHeader()->getNumber()
1635 << " Depth=" << Loop->getLoopDepth() << '\n';
1639 /// PrintChildLoopComment - Print comments about child loops within
1640 /// the loop for this basic block, with nesting.
1641 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1642 unsigned FunctionNumber) {
1643 // Add child loop information
1644 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
1645 OS.indent((*CL)->getLoopDepth()*2)
1646 << "Child Loop BB" << FunctionNumber << "_"
1647 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
1649 PrintChildLoopComment(OS, *CL, FunctionNumber);
1653 /// PrintBasicBlockLoopComments - Pretty-print comments for basic blocks.
1654 static void PrintBasicBlockLoopComments(const MachineBasicBlock &MBB,
1655 const MachineLoopInfo *LI,
1656 const AsmPrinter &AP) {
1657 // Add loop depth information
1658 const MachineLoop *Loop = LI->getLoopFor(&MBB);
1659 if (Loop == 0) return;
1661 MachineBasicBlock *Header = Loop->getHeader();
1662 assert(Header && "No header for loop");
1664 // If this block is not a loop header, just print out what is the loop header
1666 if (Header != &MBB) {
1667 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
1668 Twine(AP.getFunctionNumber())+"_" +
1669 Twine(Loop->getHeader()->getNumber())+
1670 " Depth="+Twine(Loop->getLoopDepth()));
1674 // Otherwise, it is a loop header. Print out information about child and
1676 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
1678 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
1681 OS.indent(Loop->getLoopDepth()*2-2);
1686 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
1688 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
1692 /// EmitBasicBlockStart - This method prints the label for the specified
1693 /// MachineBasicBlock, an alignment (if present) and a comment describing
1694 /// it if appropriate.
1695 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
1696 // Emit an alignment directive for this block, if needed.
1697 if (unsigned Align = MBB->getAlignment())
1698 EmitAlignment(Log2_32(Align));
1700 // If the block has its address taken, emit a special label to satisfy
1701 // references to the block. This is done so that we don't need to
1702 // remember the number of this label, and so that we can make
1703 // forward references to labels without knowing what their numbers
1705 if (MBB->hasAddressTaken()) {
1706 const BasicBlock *BB = MBB->getBasicBlock();
1708 OutStreamer.AddComment("Address Taken");
1709 OutStreamer.EmitLabel(GetBlockAddressSymbol(BB));
1712 // Print the main label for the block.
1713 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
1715 // NOTE: Want this comment at start of line.
1716 O << MAI->getCommentString() << " BB#" << MBB->getNumber() << ':';
1717 if (const BasicBlock *BB = MBB->getBasicBlock())
1719 OutStreamer.AddComment("%" + BB->getName());
1721 PrintBasicBlockLoopComments(*MBB, LI, *this);
1722 OutStreamer.AddBlankLine();
1726 if (const BasicBlock *BB = MBB->getBasicBlock())
1728 OutStreamer.AddComment("%" + BB->getName());
1729 PrintBasicBlockLoopComments(*MBB, LI, *this);
1732 OutStreamer.EmitLabel(MBB->getSymbol());
1736 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility) const {
1737 MCSymbolAttr Attr = MCSA_Invalid;
1739 switch (Visibility) {
1741 case GlobalValue::HiddenVisibility:
1742 Attr = MAI->getHiddenVisibilityAttr();
1744 case GlobalValue::ProtectedVisibility:
1745 Attr = MAI->getProtectedVisibilityAttr();
1749 if (Attr != MCSA_Invalid)
1750 OutStreamer.EmitSymbolAttribute(Sym, Attr);
1753 void AsmPrinter::printOffset(int64_t Offset) const {
1756 else if (Offset < 0)
1760 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
1761 /// exactly one predecessor and the control transfer mechanism between
1762 /// the predecessor and this block is a fall-through.
1763 bool AsmPrinter::isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB)
1765 // If this is a landing pad, it isn't a fall through. If it has no preds,
1766 // then nothing falls through to it.
1767 if (MBB->isLandingPad() || MBB->pred_empty())
1770 // If there isn't exactly one predecessor, it can't be a fall through.
1771 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
1773 if (PI2 != MBB->pred_end())
1776 // The predecessor has to be immediately before this block.
1777 const MachineBasicBlock *Pred = *PI;
1779 if (!Pred->isLayoutSuccessor(MBB))
1782 // If the block is completely empty, then it definitely does fall through.
1786 // Otherwise, check the last instruction.
1787 const MachineInstr &LastInst = Pred->back();
1788 return !LastInst.getDesc().isBarrier();
1793 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1794 if (!S->usesMetadata())
1797 gcp_iterator GCPI = GCMetadataPrinters.find(S);
1798 if (GCPI != GCMetadataPrinters.end())
1799 return GCPI->second;
1801 const char *Name = S->getName().c_str();
1803 for (GCMetadataPrinterRegistry::iterator
1804 I = GCMetadataPrinterRegistry::begin(),
1805 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1806 if (strcmp(Name, I->getName()) == 0) {
1807 GCMetadataPrinter *GMP = I->instantiate();
1809 GCMetadataPrinters.insert(std::make_pair(S, GMP));
1813 llvm_report_error("no GCMetadataPrinter registered for GC: " + Twine(Name));