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/DebugInfo.h"
29 #include "llvm/MC/MCContext.h"
30 #include "llvm/MC/MCExpr.h"
31 #include "llvm/MC/MCInst.h"
32 #include "llvm/MC/MCSection.h"
33 #include "llvm/MC/MCStreamer.h"
34 #include "llvm/MC/MCSymbol.h"
35 #include "llvm/MC/MCAsmInfo.h"
36 #include "llvm/Target/Mangler.h"
37 #include "llvm/Target/TargetData.h"
38 #include "llvm/Target/TargetInstrInfo.h"
39 #include "llvm/Target/TargetLowering.h"
40 #include "llvm/Target/TargetLoweringObjectFile.h"
41 #include "llvm/Target/TargetOptions.h"
42 #include "llvm/Target/TargetRegisterInfo.h"
43 #include "llvm/ADT/SmallPtrSet.h"
44 #include "llvm/ADT/SmallString.h"
45 #include "llvm/ADT/Statistic.h"
46 #include "llvm/Support/CommandLine.h"
47 #include "llvm/Support/Debug.h"
48 #include "llvm/Support/ErrorHandling.h"
49 #include "llvm/Support/Format.h"
50 #include "llvm/Support/FormattedStream.h"
54 STATISTIC(EmittedInsts, "Number of machine instrs printed");
56 static cl::opt<cl::boolOrDefault>
57 AsmVerbose("asm-verbose", cl::desc("Add comments to directives."),
58 cl::init(cl::BOU_UNSET));
60 static bool getVerboseAsm(bool VDef) {
63 case cl::BOU_UNSET: return VDef;
64 case cl::BOU_TRUE: return true;
65 case cl::BOU_FALSE: return false;
69 char AsmPrinter::ID = 0;
70 AsmPrinter::AsmPrinter(formatted_raw_ostream &o, TargetMachine &tm,
71 const MCAsmInfo *T, bool VDef)
72 : MachineFunctionPass(&ID), O(o),
73 TM(tm), MAI(T), TRI(tm.getRegisterInfo()),
75 OutContext(*new MCContext()),
76 // FIXME: Pass instprinter to streamer.
77 OutStreamer(*createAsmStreamer(OutContext, O, *T,
78 TM.getTargetData()->isLittleEndian(),
79 getVerboseAsm(VDef), 0)),
81 LastMI(0), LastFn(0), Counter(~0U), PrevDLT(NULL) {
83 VerboseAsm = getVerboseAsm(VDef);
86 AsmPrinter::~AsmPrinter() {
87 for (gcp_iterator I = GCMetadataPrinters.begin(),
88 E = GCMetadataPrinters.end(); I != E; ++I)
95 /// getFunctionNumber - Return a unique ID for the current function.
97 unsigned AsmPrinter::getFunctionNumber() const {
98 return MF->getFunctionNumber();
101 TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
102 return TM.getTargetLowering()->getObjFileLowering();
105 /// getCurrentSection() - Return the current section we are emitting to.
106 const MCSection *AsmPrinter::getCurrentSection() const {
107 return OutStreamer.getCurrentSection();
111 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
112 AU.setPreservesAll();
113 MachineFunctionPass::getAnalysisUsage(AU);
114 AU.addRequired<GCModuleInfo>();
116 AU.addRequired<MachineLoopInfo>();
119 bool AsmPrinter::doInitialization(Module &M) {
120 // Initialize TargetLoweringObjectFile.
121 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
122 .Initialize(OutContext, TM);
124 Mang = new Mangler(*MAI);
126 // Allow the target to emit any magic that it wants at the start of the file.
127 EmitStartOfAsmFile(M);
129 // Very minimal debug info. It is ignored if we emit actual debug info. If we
130 // don't, this at least helps the user find where a global came from.
131 if (MAI->hasSingleParameterDotFile()) {
133 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
136 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
137 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
138 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
139 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
140 MP->beginAssembly(O, *this, *MAI);
142 if (!M.getModuleInlineAsm().empty())
143 O << MAI->getCommentString() << " Start of file scope inline assembly\n"
144 << M.getModuleInlineAsm()
145 << '\n' << MAI->getCommentString()
146 << " End of file scope inline assembly\n";
148 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
150 MMI->AnalyzeModule(M);
151 DW = getAnalysisIfAvailable<DwarfWriter>();
153 DW->BeginModule(&M, MMI, O, this, MAI);
158 void AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const {
159 switch ((GlobalValue::LinkageTypes)Linkage) {
160 case GlobalValue::CommonLinkage:
161 case GlobalValue::LinkOnceAnyLinkage:
162 case GlobalValue::LinkOnceODRLinkage:
163 case GlobalValue::WeakAnyLinkage:
164 case GlobalValue::WeakODRLinkage:
165 case GlobalValue::LinkerPrivateLinkage:
166 if (MAI->getWeakDefDirective() != 0) {
168 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
169 // .weak_definition _foo
170 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
171 } else if (const char *LinkOnce = MAI->getLinkOnceDirective()) {
173 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
174 // FIXME: linkonce should be a section attribute, handled by COFF Section
176 // http://sourceware.org/binutils/docs-2.20/as/Linkonce.html#Linkonce
178 // FIXME: It would be nice to use .linkonce samesize for non-common
183 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
186 case GlobalValue::DLLExportLinkage:
187 case GlobalValue::AppendingLinkage:
188 // FIXME: appending linkage variables should go into a section of
189 // their name or something. For now, just emit them as external.
190 case GlobalValue::ExternalLinkage:
191 // If external or appending, declare as a global symbol.
193 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
195 case GlobalValue::PrivateLinkage:
196 case GlobalValue::InternalLinkage:
199 llvm_unreachable("Unknown linkage type!");
204 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
205 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
206 if (!GV->hasInitializer()) // External globals require no code.
209 // Check to see if this is a special global used by LLVM, if so, emit it.
210 if (EmitSpecialLLVMGlobal(GV))
213 MCSymbol *GVSym = GetGlobalValueSymbol(GV);
214 EmitVisibility(GVSym, GV->getVisibility());
216 if (MAI->hasDotTypeDotSizeDirective())
217 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
219 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
221 const TargetData *TD = TM.getTargetData();
222 unsigned Size = TD->getTypeAllocSize(GV->getType()->getElementType());
223 unsigned AlignLog = TD->getPreferredAlignmentLog(GV);
225 // Handle common and BSS local symbols (.lcomm).
226 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
227 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
230 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
231 /*PrintType=*/false, GV->getParent());
232 OutStreamer.GetCommentOS() << '\n';
235 // Handle common symbols.
236 if (GVKind.isCommon()) {
238 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
242 // Handle local BSS symbols.
243 if (MAI->hasMachoZeroFillDirective()) {
244 const MCSection *TheSection =
245 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
246 // .zerofill __DATA, __bss, _foo, 400, 5
247 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
251 if (MAI->hasLCOMMDirective()) {
253 OutStreamer.EmitLocalCommonSymbol(GVSym, Size);
258 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
260 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
264 const MCSection *TheSection =
265 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
267 // Handle the zerofill directive on darwin, which is a special form of BSS
269 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
271 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
272 // .zerofill __DATA, __common, _foo, 400, 5
273 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
277 OutStreamer.SwitchSection(TheSection);
279 EmitLinkage(GV->getLinkage(), GVSym);
280 EmitAlignment(AlignLog, GV);
283 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
284 /*PrintType=*/false, GV->getParent());
285 OutStreamer.GetCommentOS() << '\n';
287 OutStreamer.EmitLabel(GVSym);
289 EmitGlobalConstant(GV->getInitializer());
291 if (MAI->hasDotTypeDotSizeDirective())
293 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
295 OutStreamer.AddBlankLine();
298 /// EmitFunctionHeader - This method emits the header for the current
300 void AsmPrinter::EmitFunctionHeader() {
301 // Print out constants referenced by the function
304 // Print the 'header' of function.
305 const Function *F = MF->getFunction();
307 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
308 EmitVisibility(CurrentFnSym, F->getVisibility());
310 EmitLinkage(F->getLinkage(), CurrentFnSym);
311 EmitAlignment(MF->getAlignment(), F);
313 if (MAI->hasDotTypeDotSizeDirective())
314 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
317 WriteAsOperand(OutStreamer.GetCommentOS(), F,
318 /*PrintType=*/false, F->getParent());
319 OutStreamer.GetCommentOS() << '\n';
322 // Emit the CurrentFnSym. This is is a virtual function to allow targets to
323 // do their wild and crazy things as required.
324 EmitFunctionEntryLabel();
326 // Add some workaround for linkonce linkage on Cygwin\MinGW.
327 if (MAI->getLinkOnceDirective() != 0 &&
328 (F->hasLinkOnceLinkage() || F->hasWeakLinkage()))
329 // FIXME: What is this?
330 O << "Lllvm$workaround$fake$stub$" << *CurrentFnSym << ":\n";
332 // Emit pre-function debug and/or EH information.
333 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
334 DW->BeginFunction(MF);
337 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
338 /// function. This can be overridden by targets as required to do custom stuff.
339 void AsmPrinter::EmitFunctionEntryLabel() {
340 OutStreamer.EmitLabel(CurrentFnSym);
344 /// EmitFunctionBody - This method emits the body and trailer for a
346 void AsmPrinter::EmitFunctionBody() {
347 // Print out code for the function.
348 bool HasAnyRealCode = false;
349 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
351 // Print a label for the basic block.
352 EmitBasicBlockStart(I);
353 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
355 // Print the assembly for the instruction.
357 HasAnyRealCode = true;
361 // FIXME: Clean up processDebugLoc.
362 processDebugLoc(II, true);
370 // FIXME: Clean up processDebugLoc.
371 processDebugLoc(II, false);
375 // If the function is empty and the object file uses .subsections_via_symbols,
376 // then we need to emit *something* to the function body to prevent the
377 // labels from collapsing together. Just emit a 0 byte.
378 if (MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)
379 OutStreamer.EmitIntValue(0, 1, 0/*addrspace*/);
381 if (MAI->hasDotTypeDotSizeDirective())
382 O << "\t.size\t" << *CurrentFnSym << ", .-" << *CurrentFnSym << '\n';
384 // Emit post-function debug information.
385 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
388 // Print out jump tables referenced by the function.
393 bool AsmPrinter::doFinalization(Module &M) {
394 // Emit global variables.
395 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
397 EmitGlobalVariable(I);
399 // Emit final debug information.
400 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
403 // If the target wants to know about weak references, print them all.
404 if (MAI->getWeakRefDirective()) {
405 // FIXME: This is not lazy, it would be nice to only print weak references
406 // to stuff that is actually used. Note that doing so would require targets
407 // to notice uses in operands (due to constant exprs etc). This should
408 // happen with the MC stuff eventually.
410 // Print out module-level global variables here.
411 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
413 if (!I->hasExternalWeakLinkage()) continue;
414 OutStreamer.EmitSymbolAttribute(GetGlobalValueSymbol(I),
418 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
419 if (!I->hasExternalWeakLinkage()) continue;
420 OutStreamer.EmitSymbolAttribute(GetGlobalValueSymbol(I),
425 if (MAI->hasSetDirective()) {
426 OutStreamer.AddBlankLine();
427 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
429 MCSymbol *Name = GetGlobalValueSymbol(I);
431 const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
432 MCSymbol *Target = GetGlobalValueSymbol(GV);
434 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
435 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
436 else if (I->hasWeakLinkage())
437 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
439 assert(I->hasLocalLinkage() && "Invalid alias linkage");
441 EmitVisibility(Name, I->getVisibility());
443 // Emit the directives as assignments aka .set:
444 OutStreamer.EmitAssignment(Name,
445 MCSymbolRefExpr::Create(Target, OutContext));
449 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
450 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
451 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
452 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
453 MP->finishAssembly(O, *this, *MAI);
455 // If we don't have any trampolines, then we don't require stack memory
456 // to be executable. Some targets have a directive to declare this.
457 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
458 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
459 if (MCSection *S = MAI->getNonexecutableStackSection(OutContext))
460 OutStreamer.SwitchSection(S);
462 // Allow the target to emit any magic that it wants at the end of the file,
463 // after everything else has gone out.
466 delete Mang; Mang = 0;
469 OutStreamer.Finish();
473 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
475 // Get the function symbol.
476 CurrentFnSym = GetGlobalValueSymbol(MF.getFunction());
479 LI = &getAnalysis<MachineLoopInfo>();
483 // SectionCPs - Keep track the alignment, constpool entries per Section.
487 SmallVector<unsigned, 4> CPEs;
488 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
492 /// EmitConstantPool - Print to the current output stream assembly
493 /// representations of the constants in the constant pool MCP. This is
494 /// used to print out constants which have been "spilled to memory" by
495 /// the code generator.
497 void AsmPrinter::EmitConstantPool() {
498 const MachineConstantPool *MCP = MF->getConstantPool();
499 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
500 if (CP.empty()) return;
502 // Calculate sections for constant pool entries. We collect entries to go into
503 // the same section together to reduce amount of section switch statements.
504 SmallVector<SectionCPs, 4> CPSections;
505 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
506 const MachineConstantPoolEntry &CPE = CP[i];
507 unsigned Align = CPE.getAlignment();
510 switch (CPE.getRelocationInfo()) {
511 default: llvm_unreachable("Unknown section kind");
512 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
514 Kind = SectionKind::getReadOnlyWithRelLocal();
517 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
518 case 4: Kind = SectionKind::getMergeableConst4(); break;
519 case 8: Kind = SectionKind::getMergeableConst8(); break;
520 case 16: Kind = SectionKind::getMergeableConst16();break;
521 default: Kind = SectionKind::getMergeableConst(); break;
525 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
527 // The number of sections are small, just do a linear search from the
528 // last section to the first.
530 unsigned SecIdx = CPSections.size();
531 while (SecIdx != 0) {
532 if (CPSections[--SecIdx].S == S) {
538 SecIdx = CPSections.size();
539 CPSections.push_back(SectionCPs(S, Align));
542 if (Align > CPSections[SecIdx].Alignment)
543 CPSections[SecIdx].Alignment = Align;
544 CPSections[SecIdx].CPEs.push_back(i);
547 // Now print stuff into the calculated sections.
548 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
549 OutStreamer.SwitchSection(CPSections[i].S);
550 EmitAlignment(Log2_32(CPSections[i].Alignment));
553 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
554 unsigned CPI = CPSections[i].CPEs[j];
555 MachineConstantPoolEntry CPE = CP[CPI];
557 // Emit inter-object padding for alignment.
558 unsigned AlignMask = CPE.getAlignment() - 1;
559 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
560 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/);
562 const Type *Ty = CPE.getType();
563 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
565 // Emit the label with a comment on it.
567 OutStreamer.GetCommentOS() << "constant pool ";
568 WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(),
569 MF->getFunction()->getParent());
570 OutStreamer.GetCommentOS() << '\n';
572 OutStreamer.EmitLabel(GetCPISymbol(CPI));
574 if (CPE.isMachineConstantPoolEntry())
575 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
577 EmitGlobalConstant(CPE.Val.ConstVal);
582 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
583 /// by the current function to the current output stream.
585 void AsmPrinter::EmitJumpTableInfo() {
586 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
587 if (MJTI == 0) return;
588 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
589 if (JT.empty()) return;
591 // Pick the directive to use to print the jump table entries, and switch to
592 // the appropriate section.
593 const Function *F = MF->getFunction();
594 bool JTInDiffSection = false;
595 if (// In PIC mode, we need to emit the jump table to the same section as the
596 // function body itself, otherwise the label differences won't make sense.
597 // FIXME: Need a better predicate for this: what about custom entries?
598 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
599 // We should also do if the section name is NULL or function is declared
600 // in discardable section
601 // FIXME: this isn't the right predicate, should be based on the MCSection
603 F->isWeakForLinker()) {
604 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
606 // Otherwise, drop it in the readonly section.
607 const MCSection *ReadOnlySection =
608 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
609 OutStreamer.SwitchSection(ReadOnlySection);
610 JTInDiffSection = true;
613 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData())));
615 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
616 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
618 // If this jump table was deleted, ignore it.
619 if (JTBBs.empty()) continue;
621 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
622 // .set directive for each unique entry. This reduces the number of
623 // relocations the assembler will generate for the jump table.
624 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
625 MAI->hasSetDirective()) {
626 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
627 const TargetLowering *TLI = TM.getTargetLowering();
628 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
629 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
630 const MachineBasicBlock *MBB = JTBBs[ii];
631 if (!EmittedSets.insert(MBB)) continue;
633 // .set LJTSet, LBB32-base
635 MCSymbolRefExpr::Create(MBB->getSymbol(OutContext), OutContext);
636 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
637 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
641 // On some targets (e.g. Darwin) we want to emit two consequtive labels
642 // before each jump table. The first label is never referenced, but tells
643 // the assembler and linker the extents of the jump table object. The
644 // second label is actually referenced by the code.
645 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
646 // FIXME: This doesn't have to have any specific name, just any randomly
647 // named and numbered 'l' label would work. Simplify GetJTISymbol.
648 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
650 OutStreamer.EmitLabel(GetJTISymbol(JTI));
652 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
653 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
657 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
659 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
660 const MachineBasicBlock *MBB,
661 unsigned UID) const {
662 const MCExpr *Value = 0;
663 switch (MJTI->getEntryKind()) {
664 case MachineJumpTableInfo::EK_Custom32:
665 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
668 case MachineJumpTableInfo::EK_BlockAddress:
669 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
671 Value = MCSymbolRefExpr::Create(MBB->getSymbol(OutContext), OutContext);
673 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
674 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
675 // with a relocation as gp-relative, e.g.:
677 MCSymbol *MBBSym = MBB->getSymbol(OutContext);
678 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
682 case MachineJumpTableInfo::EK_LabelDifference32: {
683 // EK_LabelDifference32 - Each entry is the address of the block minus
684 // the address of the jump table. This is used for PIC jump tables where
685 // gprel32 is not supported. e.g.:
686 // .word LBB123 - LJTI1_2
687 // If the .set directive is supported, this is emitted as:
688 // .set L4_5_set_123, LBB123 - LJTI1_2
689 // .word L4_5_set_123
691 // If we have emitted set directives for the jump table entries, print
692 // them rather than the entries themselves. If we're emitting PIC, then
693 // emit the table entries as differences between two text section labels.
694 if (MAI->hasSetDirective()) {
695 // If we used .set, reference the .set's symbol.
696 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
700 // Otherwise, use the difference as the jump table entry.
701 Value = MCSymbolRefExpr::Create(MBB->getSymbol(OutContext), OutContext);
702 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
703 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
708 assert(Value && "Unknown entry kind!");
710 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData());
711 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0);
715 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
716 /// special global used by LLVM. If so, emit it and return true, otherwise
717 /// do nothing and return false.
718 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
719 if (GV->getName() == "llvm.used") {
720 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
721 EmitLLVMUsedList(GV->getInitializer());
725 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
726 if (GV->getSection() == "llvm.metadata" ||
727 GV->hasAvailableExternallyLinkage())
730 if (!GV->hasAppendingLinkage()) return false;
732 assert(GV->hasInitializer() && "Not a special LLVM global!");
734 const TargetData *TD = TM.getTargetData();
735 unsigned Align = Log2_32(TD->getPointerPrefAlignment());
736 if (GV->getName() == "llvm.global_ctors") {
737 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection());
738 EmitAlignment(Align, 0);
739 EmitXXStructorList(GV->getInitializer());
741 if (TM.getRelocationModel() == Reloc::Static &&
742 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
743 StringRef Sym(".constructors_used");
744 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
750 if (GV->getName() == "llvm.global_dtors") {
751 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection());
752 EmitAlignment(Align, 0);
753 EmitXXStructorList(GV->getInitializer());
755 if (TM.getRelocationModel() == Reloc::Static &&
756 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
757 StringRef Sym(".destructors_used");
758 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
767 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
768 /// global in the specified llvm.used list for which emitUsedDirectiveFor
769 /// is true, as being used with this directive.
770 void AsmPrinter::EmitLLVMUsedList(Constant *List) {
771 // Should be an array of 'i8*'.
772 ConstantArray *InitList = dyn_cast<ConstantArray>(List);
773 if (InitList == 0) return;
775 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
776 const GlobalValue *GV =
777 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
778 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
779 OutStreamer.EmitSymbolAttribute(GetGlobalValueSymbol(GV),
784 /// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the
785 /// function pointers, ignoring the init priority.
786 void AsmPrinter::EmitXXStructorList(Constant *List) {
787 // Should be an array of '{ int, void ()* }' structs. The first value is the
788 // init priority, which we ignore.
789 if (!isa<ConstantArray>(List)) return;
790 ConstantArray *InitList = cast<ConstantArray>(List);
791 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
792 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
793 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs.
795 if (CS->getOperand(1)->isNullValue())
796 return; // Found a null terminator, exit printing.
797 // Emit the function pointer.
798 EmitGlobalConstant(CS->getOperand(1));
802 //===--------------------------------------------------------------------===//
803 // Emission and print routines
806 /// EmitInt8 - Emit a byte directive and value.
808 void AsmPrinter::EmitInt8(int Value) const {
809 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/);
812 /// EmitInt16 - Emit a short directive and value.
814 void AsmPrinter::EmitInt16(int Value) const {
815 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/);
818 /// EmitInt32 - Emit a long directive and value.
820 void AsmPrinter::EmitInt32(int Value) const {
821 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/);
824 /// EmitInt64 - Emit a long long directive and value.
826 void AsmPrinter::EmitInt64(uint64_t Value) const {
827 OutStreamer.EmitIntValue(Value, 8, 0/*addrspace*/);
830 //===----------------------------------------------------------------------===//
832 // EmitAlignment - Emit an alignment directive to the specified power of
833 // two boundary. For example, if you pass in 3 here, you will get an 8
834 // byte alignment. If a global value is specified, and if that global has
835 // an explicit alignment requested, it will unconditionally override the
836 // alignment request. However, if ForcedAlignBits is specified, this value
837 // has final say: the ultimate alignment will be the max of ForcedAlignBits
838 // and the alignment computed with NumBits and the global.
842 // if (GV && GV->hasalignment) Align = GV->getalignment();
843 // Align = std::max(Align, ForcedAlignBits);
845 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
846 unsigned ForcedAlignBits,
847 bool UseFillExpr) const {
848 if (GV && GV->getAlignment())
849 NumBits = Log2_32(GV->getAlignment());
850 NumBits = std::max(NumBits, ForcedAlignBits);
852 if (NumBits == 0) return; // No need to emit alignment.
854 unsigned FillValue = 0;
855 if (getCurrentSection()->getKind().isText())
856 FillValue = MAI->getTextAlignFillValue();
858 OutStreamer.EmitValueToAlignment(1 << NumBits, FillValue, 1, 0);
861 /// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
863 static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) {
864 MCContext &Ctx = AP.OutContext;
866 if (CV->isNullValue() || isa<UndefValue>(CV))
867 return MCConstantExpr::Create(0, Ctx);
869 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
870 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
872 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
873 return MCSymbolRefExpr::Create(AP.GetGlobalValueSymbol(GV), Ctx);
874 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
875 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
877 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
879 llvm_unreachable("Unknown constant value to lower!");
880 return MCConstantExpr::Create(0, Ctx);
883 switch (CE->getOpcode()) {
884 case Instruction::ZExt:
885 case Instruction::SExt:
886 case Instruction::FPTrunc:
887 case Instruction::FPExt:
888 case Instruction::UIToFP:
889 case Instruction::SIToFP:
890 case Instruction::FPToUI:
891 case Instruction::FPToSI:
892 default: llvm_unreachable("FIXME: Don't support this constant cast expr");
893 case Instruction::GetElementPtr: {
894 const TargetData &TD = *AP.TM.getTargetData();
895 // Generate a symbolic expression for the byte address
896 const Constant *PtrVal = CE->getOperand(0);
897 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
898 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0],
901 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
905 // Truncate/sext the offset to the pointer size.
906 if (TD.getPointerSizeInBits() != 64) {
907 int SExtAmount = 64-TD.getPointerSizeInBits();
908 Offset = (Offset << SExtAmount) >> SExtAmount;
911 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
915 case Instruction::Trunc:
916 // We emit the value and depend on the assembler to truncate the generated
917 // expression properly. This is important for differences between
918 // blockaddress labels. Since the two labels are in the same function, it
919 // is reasonable to treat their delta as a 32-bit value.
921 case Instruction::BitCast:
922 return LowerConstant(CE->getOperand(0), AP);
924 case Instruction::IntToPtr: {
925 const TargetData &TD = *AP.TM.getTargetData();
926 // Handle casts to pointers by changing them into casts to the appropriate
927 // integer type. This promotes constant folding and simplifies this code.
928 Constant *Op = CE->getOperand(0);
929 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
931 return LowerConstant(Op, AP);
934 case Instruction::PtrToInt: {
935 const TargetData &TD = *AP.TM.getTargetData();
936 // Support only foldable casts to/from pointers that can be eliminated by
937 // changing the pointer to the appropriately sized integer type.
938 Constant *Op = CE->getOperand(0);
939 const Type *Ty = CE->getType();
941 const MCExpr *OpExpr = LowerConstant(Op, AP);
943 // We can emit the pointer value into this slot if the slot is an
944 // integer slot equal to the size of the pointer.
945 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
948 // Otherwise the pointer is smaller than the resultant integer, mask off
949 // the high bits so we are sure to get a proper truncation if the input is
951 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
952 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
953 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
956 case Instruction::Add:
957 case Instruction::Sub:
958 case Instruction::And:
959 case Instruction::Or:
960 case Instruction::Xor: {
961 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP);
962 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP);
963 switch (CE->getOpcode()) {
964 default: llvm_unreachable("Unknown binary operator constant cast expr");
965 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
966 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
967 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
968 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
969 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
975 static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
977 if (AddrSpace != 0 || !CA->isString()) {
978 // Not a string. Print the values in successive locations
979 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
980 AP.EmitGlobalConstant(CA->getOperand(i), AddrSpace);
984 // Otherwise, it can be emitted as .ascii.
985 SmallVector<char, 128> TmpVec;
986 TmpVec.reserve(CA->getNumOperands());
987 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
988 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
990 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace);
993 static void EmitGlobalConstantVector(const ConstantVector *CV,
994 unsigned AddrSpace, AsmPrinter &AP) {
995 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
996 AP.EmitGlobalConstant(CV->getOperand(i), AddrSpace);
999 static void EmitGlobalConstantStruct(const ConstantStruct *CS,
1000 unsigned AddrSpace, AsmPrinter &AP) {
1001 // Print the fields in successive locations. Pad to align if needed!
1002 const TargetData *TD = AP.TM.getTargetData();
1003 unsigned Size = TD->getTypeAllocSize(CS->getType());
1004 const StructLayout *Layout = TD->getStructLayout(CS->getType());
1005 uint64_t SizeSoFar = 0;
1006 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1007 const Constant *Field = CS->getOperand(i);
1009 // Check if padding is needed and insert one or more 0s.
1010 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
1011 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1012 - Layout->getElementOffset(i)) - FieldSize;
1013 SizeSoFar += FieldSize + PadSize;
1015 // Now print the actual field value.
1016 AP.EmitGlobalConstant(Field, AddrSpace);
1018 // Insert padding - this may include padding to increase the size of the
1019 // current field up to the ABI size (if the struct is not packed) as well
1020 // as padding to ensure that the next field starts at the right offset.
1021 AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
1023 assert(SizeSoFar == Layout->getSizeInBytes() &&
1024 "Layout of constant struct may be incorrect!");
1027 static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
1029 // FP Constants are printed as integer constants to avoid losing
1031 if (CFP->getType()->isDoubleTy()) {
1032 if (AP.VerboseAsm) {
1033 double Val = CFP->getValueAPF().convertToDouble();
1034 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n';
1037 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1038 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1042 if (CFP->getType()->isFloatTy()) {
1043 if (AP.VerboseAsm) {
1044 float Val = CFP->getValueAPF().convertToFloat();
1045 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n';
1047 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1048 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace);
1052 if (CFP->getType()->isX86_FP80Ty()) {
1053 // all long double variants are printed as hex
1054 // api needed to prevent premature destruction
1055 APInt API = CFP->getValueAPF().bitcastToAPInt();
1056 const uint64_t *p = API.getRawData();
1057 if (AP.VerboseAsm) {
1058 // Convert to double so we can print the approximate val as a comment.
1059 APFloat DoubleVal = CFP->getValueAPF();
1061 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1063 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= "
1064 << DoubleVal.convertToDouble() << '\n';
1067 if (AP.TM.getTargetData()->isBigEndian()) {
1068 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1069 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1071 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1072 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1075 // Emit the tail padding for the long double.
1076 const TargetData &TD = *AP.TM.getTargetData();
1077 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
1078 TD.getTypeStoreSize(CFP->getType()), AddrSpace);
1082 assert(CFP->getType()->isPPC_FP128Ty() &&
1083 "Floating point constant type not handled");
1084 // All long double variants are printed as hex api needed to prevent
1085 // premature destruction.
1086 APInt API = CFP->getValueAPF().bitcastToAPInt();
1087 const uint64_t *p = API.getRawData();
1088 if (AP.TM.getTargetData()->isBigEndian()) {
1089 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1090 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1092 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1093 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1097 static void EmitGlobalConstantLargeInt(const ConstantInt *CI,
1098 unsigned AddrSpace, AsmPrinter &AP) {
1099 const TargetData *TD = AP.TM.getTargetData();
1100 unsigned BitWidth = CI->getBitWidth();
1101 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
1103 // We don't expect assemblers to support integer data directives
1104 // for more than 64 bits, so we emit the data in at most 64-bit
1105 // quantities at a time.
1106 const uint64_t *RawData = CI->getValue().getRawData();
1107 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1108 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1109 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1113 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1114 void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1115 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) {
1116 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1117 return OutStreamer.EmitZeros(Size, AddrSpace);
1120 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1121 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1128 OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue());
1129 OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1132 EmitGlobalConstantLargeInt(CI, AddrSpace, *this);
1137 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1138 return EmitGlobalConstantArray(CVA, AddrSpace, *this);
1140 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1141 return EmitGlobalConstantStruct(CVS, AddrSpace, *this);
1143 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1144 return EmitGlobalConstantFP(CFP, AddrSpace, *this);
1146 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1147 return EmitGlobalConstantVector(V, AddrSpace, *this);
1149 if (isa<ConstantPointerNull>(CV)) {
1150 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1151 OutStreamer.EmitIntValue(0, Size, AddrSpace);
1155 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1156 // thread the streamer with EmitValue.
1157 OutStreamer.EmitValue(LowerConstant(CV, *this),
1158 TM.getTargetData()->getTypeAllocSize(CV->getType()),
1162 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1163 // Target doesn't support this yet!
1164 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1167 /// PrintSpecial - Print information related to the specified machine instr
1168 /// that is independent of the operand, and may be independent of the instr
1169 /// itself. This can be useful for portably encoding the comment character
1170 /// or other bits of target-specific knowledge into the asmstrings. The
1171 /// syntax used is ${:comment}. Targets can override this to add support
1172 /// for their own strange codes.
1173 void AsmPrinter::PrintSpecial(const MachineInstr *MI, const char *Code) const {
1174 if (!strcmp(Code, "private")) {
1175 O << MAI->getPrivateGlobalPrefix();
1176 } else if (!strcmp(Code, "comment")) {
1178 O << MAI->getCommentString();
1179 } else if (!strcmp(Code, "uid")) {
1180 // Comparing the address of MI isn't sufficient, because machineinstrs may
1181 // be allocated to the same address across functions.
1182 const Function *ThisF = MI->getParent()->getParent()->getFunction();
1184 // If this is a new LastFn instruction, bump the counter.
1185 if (LastMI != MI || LastFn != ThisF) {
1193 raw_string_ostream Msg(msg);
1194 Msg << "Unknown special formatter '" << Code
1195 << "' for machine instr: " << *MI;
1196 llvm_report_error(Msg.str());
1200 /// processDebugLoc - Processes the debug information of each machine
1201 /// instruction's DebugLoc.
1202 void AsmPrinter::processDebugLoc(const MachineInstr *MI,
1203 bool BeforePrintingInsn) {
1204 if (!MAI || !DW || !MAI->doesSupportDebugInformation()
1205 || !DW->ShouldEmitDwarfDebug())
1207 DebugLoc DL = MI->getDebugLoc();
1210 DILocation CurDLT = MF->getDILocation(DL);
1211 if (CurDLT.getScope().isNull())
1214 if (!BeforePrintingInsn) {
1215 // After printing instruction
1217 } else if (CurDLT.getNode() != PrevDLT) {
1218 unsigned L = DW->RecordSourceLine(CurDLT.getLineNumber(),
1219 CurDLT.getColumnNumber(),
1220 CurDLT.getScope().getNode());
1223 DW->BeginScope(MI, L);
1224 PrevDLT = CurDLT.getNode();
1229 /// printInlineAsm - This method formats and prints the specified machine
1230 /// instruction that is an inline asm.
1231 void AsmPrinter::printInlineAsm(const MachineInstr *MI) const {
1232 unsigned NumOperands = MI->getNumOperands();
1234 // Count the number of register definitions.
1235 unsigned NumDefs = 0;
1236 for (; MI->getOperand(NumDefs).isReg() && MI->getOperand(NumDefs).isDef();
1238 assert(NumDefs != NumOperands-1 && "No asm string?");
1240 assert(MI->getOperand(NumDefs).isSymbol() && "No asm string?");
1242 // Disassemble the AsmStr, printing out the literal pieces, the operands, etc.
1243 const char *AsmStr = MI->getOperand(NumDefs).getSymbolName();
1247 // If this asmstr is empty, just print the #APP/#NOAPP markers.
1248 // These are useful to see where empty asm's wound up.
1249 if (AsmStr[0] == 0) {
1250 O << MAI->getCommentString() << MAI->getInlineAsmStart() << "\n\t";
1251 O << MAI->getCommentString() << MAI->getInlineAsmEnd() << '\n';
1255 O << MAI->getCommentString() << MAI->getInlineAsmStart() << "\n\t";
1257 // The variant of the current asmprinter.
1258 int AsmPrinterVariant = MAI->getAssemblerDialect();
1260 int CurVariant = -1; // The number of the {.|.|.} region we are in.
1261 const char *LastEmitted = AsmStr; // One past the last character emitted.
1263 while (*LastEmitted) {
1264 switch (*LastEmitted) {
1266 // Not a special case, emit the string section literally.
1267 const char *LiteralEnd = LastEmitted+1;
1268 while (*LiteralEnd && *LiteralEnd != '{' && *LiteralEnd != '|' &&
1269 *LiteralEnd != '}' && *LiteralEnd != '$' && *LiteralEnd != '\n')
1271 if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1272 O.write(LastEmitted, LiteralEnd-LastEmitted);
1273 LastEmitted = LiteralEnd;
1277 ++LastEmitted; // Consume newline character.
1278 O << '\n'; // Indent code with newline.
1281 ++LastEmitted; // Consume '$' character.
1285 switch (*LastEmitted) {
1286 default: Done = false; break;
1287 case '$': // $$ -> $
1288 if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1290 ++LastEmitted; // Consume second '$' character.
1292 case '(': // $( -> same as GCC's { character.
1293 ++LastEmitted; // Consume '(' character.
1294 if (CurVariant != -1) {
1295 llvm_report_error("Nested variants found in inline asm string: '"
1296 + std::string(AsmStr) + "'");
1298 CurVariant = 0; // We're in the first variant now.
1301 ++LastEmitted; // consume '|' character.
1302 if (CurVariant == -1)
1303 O << '|'; // this is gcc's behavior for | outside a variant
1305 ++CurVariant; // We're in the next variant.
1307 case ')': // $) -> same as GCC's } char.
1308 ++LastEmitted; // consume ')' character.
1309 if (CurVariant == -1)
1310 O << '}'; // this is gcc's behavior for } outside a variant
1317 bool HasCurlyBraces = false;
1318 if (*LastEmitted == '{') { // ${variable}
1319 ++LastEmitted; // Consume '{' character.
1320 HasCurlyBraces = true;
1323 // If we have ${:foo}, then this is not a real operand reference, it is a
1324 // "magic" string reference, just like in .td files. Arrange to call
1326 if (HasCurlyBraces && *LastEmitted == ':') {
1328 const char *StrStart = LastEmitted;
1329 const char *StrEnd = strchr(StrStart, '}');
1331 llvm_report_error("Unterminated ${:foo} operand in inline asm string: '"
1332 + std::string(AsmStr) + "'");
1335 std::string Val(StrStart, StrEnd);
1336 PrintSpecial(MI, Val.c_str());
1337 LastEmitted = StrEnd+1;
1341 const char *IDStart = LastEmitted;
1344 long Val = strtol(IDStart, &IDEnd, 10); // We only accept numbers for IDs.
1345 if (!isdigit(*IDStart) || (Val == 0 && errno == EINVAL)) {
1346 llvm_report_error("Bad $ operand number in inline asm string: '"
1347 + std::string(AsmStr) + "'");
1349 LastEmitted = IDEnd;
1351 char Modifier[2] = { 0, 0 };
1353 if (HasCurlyBraces) {
1354 // If we have curly braces, check for a modifier character. This
1355 // supports syntax like ${0:u}, which correspond to "%u0" in GCC asm.
1356 if (*LastEmitted == ':') {
1357 ++LastEmitted; // Consume ':' character.
1358 if (*LastEmitted == 0) {
1359 llvm_report_error("Bad ${:} expression in inline asm string: '"
1360 + std::string(AsmStr) + "'");
1363 Modifier[0] = *LastEmitted;
1364 ++LastEmitted; // Consume modifier character.
1367 if (*LastEmitted != '}') {
1368 llvm_report_error("Bad ${} expression in inline asm string: '"
1369 + std::string(AsmStr) + "'");
1371 ++LastEmitted; // Consume '}' character.
1374 if ((unsigned)Val >= NumOperands-1) {
1375 llvm_report_error("Invalid $ operand number in inline asm string: '"
1376 + std::string(AsmStr) + "'");
1379 // Okay, we finally have a value number. Ask the target to print this
1381 if (CurVariant == -1 || CurVariant == AsmPrinterVariant) {
1386 // Scan to find the machine operand number for the operand.
1387 for (; Val; --Val) {
1388 if (OpNo >= MI->getNumOperands()) break;
1389 unsigned OpFlags = MI->getOperand(OpNo).getImm();
1390 OpNo += InlineAsm::getNumOperandRegisters(OpFlags) + 1;
1393 if (OpNo >= MI->getNumOperands()) {
1396 unsigned OpFlags = MI->getOperand(OpNo).getImm();
1397 ++OpNo; // Skip over the ID number.
1399 if (Modifier[0] == 'l') // labels are target independent
1400 O << *MI->getOperand(OpNo).getMBB()->getSymbol(OutContext);
1402 AsmPrinter *AP = const_cast<AsmPrinter*>(this);
1403 if ((OpFlags & 7) == 4) {
1404 Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant,
1405 Modifier[0] ? Modifier : 0);
1407 Error = AP->PrintAsmOperand(MI, OpNo, AsmPrinterVariant,
1408 Modifier[0] ? Modifier : 0);
1414 raw_string_ostream Msg(msg);
1415 Msg << "Invalid operand found in inline asm: '" << AsmStr << "'\n";
1417 llvm_report_error(Msg.str());
1424 O << "\n\t" << MAI->getCommentString() << MAI->getInlineAsmEnd();
1427 /// printImplicitDef - This method prints the specified machine instruction
1428 /// that is an implicit def.
1429 void AsmPrinter::printImplicitDef(const MachineInstr *MI) const {
1430 if (!VerboseAsm) return;
1431 O.PadToColumn(MAI->getCommentColumn());
1432 O << MAI->getCommentString() << " implicit-def: "
1433 << TRI->getName(MI->getOperand(0).getReg());
1436 void AsmPrinter::printKill(const MachineInstr *MI) const {
1437 if (!VerboseAsm) return;
1438 O.PadToColumn(MAI->getCommentColumn());
1439 O << MAI->getCommentString() << " kill:";
1440 for (unsigned n = 0, e = MI->getNumOperands(); n != e; ++n) {
1441 const MachineOperand &op = MI->getOperand(n);
1442 assert(op.isReg() && "KILL instruction must have only register operands");
1443 O << ' ' << TRI->getName(op.getReg()) << (op.isDef() ? "<def>" : "<kill>");
1447 /// printLabel - This method prints a local label used by debug and
1448 /// exception handling tables.
1449 void AsmPrinter::printLabel(const MachineInstr *MI) const {
1450 printLabel(MI->getOperand(0).getImm());
1453 void AsmPrinter::printLabel(unsigned Id) const {
1454 O << MAI->getPrivateGlobalPrefix() << "label" << Id << ':';
1457 /// PrintAsmOperand - Print the specified operand of MI, an INLINEASM
1458 /// instruction, using the specified assembler variant. Targets should
1459 /// override this to format as appropriate.
1460 bool AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
1461 unsigned AsmVariant, const char *ExtraCode) {
1462 // Target doesn't support this yet!
1466 bool AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
1467 unsigned AsmVariant,
1468 const char *ExtraCode) {
1469 // Target doesn't support this yet!
1473 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA,
1474 const char *Suffix) const {
1475 return GetBlockAddressSymbol(BA->getFunction(), BA->getBasicBlock(), Suffix);
1478 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const Function *F,
1479 const BasicBlock *BB,
1480 const char *Suffix) const {
1481 assert(BB->hasName() &&
1482 "Address of anonymous basic block not supported yet!");
1484 // This code must use the function name itself, and not the function number,
1485 // since it must be possible to generate the label name from within other
1487 SmallString<60> FnName;
1488 Mang->getNameWithPrefix(FnName, F, false);
1490 // FIXME: THIS IS BROKEN IF THE LLVM BASIC BLOCK DOESN'T HAVE A NAME!
1491 SmallString<60> NameResult;
1492 Mang->getNameWithPrefix(NameResult,
1493 StringRef("BA") + Twine((unsigned)FnName.size()) +
1494 "_" + FnName.str() + "_" + BB->getName() + Suffix,
1497 return OutContext.GetOrCreateSymbol(NameResult.str());
1500 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1501 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1502 SmallString<60> Name;
1503 raw_svector_ostream(Name) << MAI->getPrivateGlobalPrefix() << "CPI"
1504 << getFunctionNumber() << '_' << CPID;
1505 return OutContext.GetOrCreateSymbol(Name.str());
1508 /// GetJTISymbol - Return the symbol for the specified jump table entry.
1509 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1510 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
1513 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
1514 /// FIXME: privatize to AsmPrinter.
1515 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
1516 SmallString<60> Name;
1517 raw_svector_ostream(Name) << MAI->getPrivateGlobalPrefix()
1518 << getFunctionNumber() << '_' << UID << "_set_" << MBBID;
1519 return OutContext.GetOrCreateSymbol(Name.str());
1522 /// GetGlobalValueSymbol - Return the MCSymbol for the specified global
1524 MCSymbol *AsmPrinter::GetGlobalValueSymbol(const GlobalValue *GV) const {
1525 SmallString<60> NameStr;
1526 Mang->getNameWithPrefix(NameStr, GV, false);
1527 return OutContext.GetOrCreateSymbol(NameStr.str());
1530 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1531 /// global value name as its base, with the specified suffix, and where the
1532 /// symbol is forced to have private linkage if ForcePrivate is true.
1533 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1535 bool ForcePrivate) const {
1536 SmallString<60> NameStr;
1537 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1538 NameStr.append(Suffix.begin(), Suffix.end());
1539 return OutContext.GetOrCreateSymbol(NameStr.str());
1542 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
1544 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
1545 SmallString<60> NameStr;
1546 Mang->getNameWithPrefix(NameStr, Sym);
1547 return OutContext.GetOrCreateSymbol(NameStr.str());
1552 /// PrintParentLoopComment - Print comments about parent loops of this one.
1553 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1554 unsigned FunctionNumber) {
1555 if (Loop == 0) return;
1556 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
1557 OS.indent(Loop->getLoopDepth()*2)
1558 << "Parent Loop BB" << FunctionNumber << "_"
1559 << Loop->getHeader()->getNumber()
1560 << " Depth=" << Loop->getLoopDepth() << '\n';
1564 /// PrintChildLoopComment - Print comments about child loops within
1565 /// the loop for this basic block, with nesting.
1566 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1567 unsigned FunctionNumber) {
1568 // Add child loop information
1569 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
1570 OS.indent((*CL)->getLoopDepth()*2)
1571 << "Child Loop BB" << FunctionNumber << "_"
1572 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
1574 PrintChildLoopComment(OS, *CL, FunctionNumber);
1578 /// EmitComments - Pretty-print comments for basic blocks.
1579 static void PrintBasicBlockLoopComments(const MachineBasicBlock &MBB,
1580 const MachineLoopInfo *LI,
1581 const AsmPrinter &AP) {
1582 // Add loop depth information
1583 const MachineLoop *Loop = LI->getLoopFor(&MBB);
1584 if (Loop == 0) return;
1586 MachineBasicBlock *Header = Loop->getHeader();
1587 assert(Header && "No header for loop");
1589 // If this block is not a loop header, just print out what is the loop header
1591 if (Header != &MBB) {
1592 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
1593 Twine(AP.getFunctionNumber())+"_" +
1594 Twine(Loop->getHeader()->getNumber())+
1595 " Depth="+Twine(Loop->getLoopDepth()));
1599 // Otherwise, it is a loop header. Print out information about child and
1601 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
1603 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
1606 OS.indent(Loop->getLoopDepth()*2-2);
1611 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
1613 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
1617 /// EmitBasicBlockStart - This method prints the label for the specified
1618 /// MachineBasicBlock, an alignment (if present) and a comment describing
1619 /// it if appropriate.
1620 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
1621 // Emit an alignment directive for this block, if needed.
1622 if (unsigned Align = MBB->getAlignment())
1623 EmitAlignment(Log2_32(Align));
1625 // If the block has its address taken, emit a special label to satisfy
1626 // references to the block. This is done so that we don't need to
1627 // remember the number of this label, and so that we can make
1628 // forward references to labels without knowing what their numbers
1630 if (MBB->hasAddressTaken()) {
1631 const BasicBlock *BB = MBB->getBasicBlock();
1633 OutStreamer.AddComment("Address Taken");
1634 OutStreamer.EmitLabel(GetBlockAddressSymbol(BB->getParent(), BB));
1637 // Print the main label for the block.
1638 if (MBB->pred_empty() || MBB->isOnlyReachableByFallthrough()) {
1640 // NOTE: Want this comment at start of line.
1641 O << MAI->getCommentString() << " BB#" << MBB->getNumber() << ':';
1642 if (const BasicBlock *BB = MBB->getBasicBlock())
1644 OutStreamer.AddComment("%" + BB->getName());
1646 PrintBasicBlockLoopComments(*MBB, LI, *this);
1647 OutStreamer.AddBlankLine();
1651 if (const BasicBlock *BB = MBB->getBasicBlock())
1653 OutStreamer.AddComment("%" + BB->getName());
1654 PrintBasicBlockLoopComments(*MBB, LI, *this);
1657 OutStreamer.EmitLabel(MBB->getSymbol(OutContext));
1661 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility) const {
1662 MCSymbolAttr Attr = MCSA_Invalid;
1664 switch (Visibility) {
1666 case GlobalValue::HiddenVisibility:
1667 Attr = MAI->getHiddenVisibilityAttr();
1669 case GlobalValue::ProtectedVisibility:
1670 Attr = MAI->getProtectedVisibilityAttr();
1674 if (Attr != MCSA_Invalid)
1675 OutStreamer.EmitSymbolAttribute(Sym, Attr);
1678 void AsmPrinter::printOffset(int64_t Offset) const {
1681 else if (Offset < 0)
1685 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1686 if (!S->usesMetadata())
1689 gcp_iterator GCPI = GCMetadataPrinters.find(S);
1690 if (GCPI != GCMetadataPrinters.end())
1691 return GCPI->second;
1693 const char *Name = S->getName().c_str();
1695 for (GCMetadataPrinterRegistry::iterator
1696 I = GCMetadataPrinterRegistry::begin(),
1697 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1698 if (strcmp(Name, I->getName()) == 0) {
1699 GCMetadataPrinter *GMP = I->instantiate();
1701 GCMetadataPrinters.insert(std::make_pair(S, GMP));
1705 llvm_report_error("no GCMetadataPrinter registered for GC: " + Twine(Name));
1709 /// EmitComments - Pretty-print comments for instructions
1710 void AsmPrinter::EmitComments(const MachineInstr &MI) const {
1714 bool Newline = false;
1716 if (!MI.getDebugLoc().isUnknown()) {
1717 DILocation DLT = MF->getDILocation(MI.getDebugLoc());
1719 // Print source line info.
1720 O.PadToColumn(MAI->getCommentColumn());
1721 O << MAI->getCommentString() << ' ';
1722 DIScope Scope = DLT.getScope();
1723 // Omit the directory, because it's likely to be long and uninteresting.
1724 if (!Scope.isNull())
1725 O << Scope.getFilename();
1728 O << ':' << DLT.getLineNumber();
1729 if (DLT.getColumnNumber() != 0)
1730 O << ':' << DLT.getColumnNumber();
1734 // Check for spills and reloads
1737 const MachineFrameInfo *FrameInfo =
1738 MI.getParent()->getParent()->getFrameInfo();
1740 // We assume a single instruction only has a spill or reload, not
1742 const MachineMemOperand *MMO;
1743 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
1744 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
1745 MMO = *MI.memoperands_begin();
1746 if (Newline) O << '\n';
1747 O.PadToColumn(MAI->getCommentColumn());
1748 O << MAI->getCommentString() << ' ' << MMO->getSize() << "-byte Reload";
1752 else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
1753 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
1754 if (Newline) O << '\n';
1755 O.PadToColumn(MAI->getCommentColumn());
1756 O << MAI->getCommentString() << ' '
1757 << MMO->getSize() << "-byte Folded Reload";
1761 else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
1762 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
1763 MMO = *MI.memoperands_begin();
1764 if (Newline) O << '\n';
1765 O.PadToColumn(MAI->getCommentColumn());
1766 O << MAI->getCommentString() << ' ' << MMO->getSize() << "-byte Spill";
1770 else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
1771 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
1772 if (Newline) O << '\n';
1773 O.PadToColumn(MAI->getCommentColumn());
1774 O << MAI->getCommentString() << ' '
1775 << MMO->getSize() << "-byte Folded Spill";
1780 // Check for spill-induced copies
1781 unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
1782 if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg,
1783 SrcSubIdx, DstSubIdx)) {
1784 if (MI.getAsmPrinterFlag(ReloadReuse)) {
1785 if (Newline) O << '\n';
1786 O.PadToColumn(MAI->getCommentColumn());
1787 O << MAI->getCommentString() << " Reload Reuse";