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 char AsmPrinter::ID = 0;
57 AsmPrinter::AsmPrinter(formatted_raw_ostream &o, TargetMachine &tm,
58 MCContext &Ctx, MCStreamer &Streamer,
60 : MachineFunctionPass(&ID), O(o),
61 TM(tm), MAI(T), TRI(tm.getRegisterInfo()),
62 OutContext(Ctx), OutStreamer(Streamer),
63 LastMI(0), LastFn(0), Counter(~0U), PrevDLT(NULL) {
65 VerboseAsm = Streamer.isVerboseAsm();
68 AsmPrinter::~AsmPrinter() {
69 for (gcp_iterator I = GCMetadataPrinters.begin(),
70 E = GCMetadataPrinters.end(); I != E; ++I)
77 /// getFunctionNumber - Return a unique ID for the current function.
79 unsigned AsmPrinter::getFunctionNumber() const {
80 return MF->getFunctionNumber();
83 TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
84 return TM.getTargetLowering()->getObjFileLowering();
87 /// getCurrentSection() - Return the current section we are emitting to.
88 const MCSection *AsmPrinter::getCurrentSection() const {
89 return OutStreamer.getCurrentSection();
93 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
95 MachineFunctionPass::getAnalysisUsage(AU);
96 AU.addRequired<GCModuleInfo>();
98 AU.addRequired<MachineLoopInfo>();
101 bool AsmPrinter::doInitialization(Module &M) {
102 // Initialize TargetLoweringObjectFile.
103 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
104 .Initialize(OutContext, TM);
106 Mang = new Mangler(*MAI);
108 // Allow the target to emit any magic that it wants at the start of the file.
109 EmitStartOfAsmFile(M);
111 // Very minimal debug info. It is ignored if we emit actual debug info. If we
112 // don't, this at least helps the user find where a global came from.
113 if (MAI->hasSingleParameterDotFile()) {
115 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
118 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
119 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
120 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
121 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
122 MP->beginAssembly(O, *this, *MAI);
124 if (!M.getModuleInlineAsm().empty())
125 O << MAI->getCommentString() << " Start of file scope inline assembly\n"
126 << M.getModuleInlineAsm()
127 << '\n' << MAI->getCommentString()
128 << " End of file scope inline assembly\n";
130 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
132 MMI->AnalyzeModule(M);
133 DW = getAnalysisIfAvailable<DwarfWriter>();
135 DW->BeginModule(&M, MMI, O, this, MAI);
140 void AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const {
141 switch ((GlobalValue::LinkageTypes)Linkage) {
142 case GlobalValue::CommonLinkage:
143 case GlobalValue::LinkOnceAnyLinkage:
144 case GlobalValue::LinkOnceODRLinkage:
145 case GlobalValue::WeakAnyLinkage:
146 case GlobalValue::WeakODRLinkage:
147 case GlobalValue::LinkerPrivateLinkage:
148 if (MAI->getWeakDefDirective() != 0) {
150 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
151 // .weak_definition _foo
152 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
153 } else if (const char *LinkOnce = MAI->getLinkOnceDirective()) {
155 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
156 // FIXME: linkonce should be a section attribute, handled by COFF Section
158 // http://sourceware.org/binutils/docs-2.20/as/Linkonce.html#Linkonce
160 // FIXME: It would be nice to use .linkonce samesize for non-common
165 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
168 case GlobalValue::DLLExportLinkage:
169 case GlobalValue::AppendingLinkage:
170 // FIXME: appending linkage variables should go into a section of
171 // their name or something. For now, just emit them as external.
172 case GlobalValue::ExternalLinkage:
173 // If external or appending, declare as a global symbol.
175 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
177 case GlobalValue::PrivateLinkage:
178 case GlobalValue::InternalLinkage:
181 llvm_unreachable("Unknown linkage type!");
186 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
187 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
188 if (!GV->hasInitializer()) // External globals require no code.
191 // Check to see if this is a special global used by LLVM, if so, emit it.
192 if (EmitSpecialLLVMGlobal(GV))
195 MCSymbol *GVSym = GetGlobalValueSymbol(GV);
196 EmitVisibility(GVSym, GV->getVisibility());
198 if (MAI->hasDotTypeDotSizeDirective())
199 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
201 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
203 const TargetData *TD = TM.getTargetData();
204 unsigned Size = TD->getTypeAllocSize(GV->getType()->getElementType());
205 unsigned AlignLog = TD->getPreferredAlignmentLog(GV);
207 // Handle common and BSS local symbols (.lcomm).
208 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
209 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
212 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
213 /*PrintType=*/false, GV->getParent());
214 OutStreamer.GetCommentOS() << '\n';
217 // Handle common symbols.
218 if (GVKind.isCommon()) {
220 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
224 // Handle local BSS symbols.
225 if (MAI->hasMachoZeroFillDirective()) {
226 const MCSection *TheSection =
227 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
228 // .zerofill __DATA, __bss, _foo, 400, 5
229 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
233 if (MAI->hasLCOMMDirective()) {
235 OutStreamer.EmitLocalCommonSymbol(GVSym, Size);
240 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
242 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
246 const MCSection *TheSection =
247 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
249 // Handle the zerofill directive on darwin, which is a special form of BSS
251 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
253 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
254 // .zerofill __DATA, __common, _foo, 400, 5
255 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
259 OutStreamer.SwitchSection(TheSection);
261 EmitLinkage(GV->getLinkage(), GVSym);
262 EmitAlignment(AlignLog, GV);
265 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
266 /*PrintType=*/false, GV->getParent());
267 OutStreamer.GetCommentOS() << '\n';
269 OutStreamer.EmitLabel(GVSym);
271 EmitGlobalConstant(GV->getInitializer());
273 if (MAI->hasDotTypeDotSizeDirective())
275 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
277 OutStreamer.AddBlankLine();
280 /// EmitFunctionHeader - This method emits the header for the current
282 void AsmPrinter::EmitFunctionHeader() {
283 // Print out constants referenced by the function
286 // Print the 'header' of function.
287 const Function *F = MF->getFunction();
289 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
290 EmitVisibility(CurrentFnSym, F->getVisibility());
292 EmitLinkage(F->getLinkage(), CurrentFnSym);
293 EmitAlignment(MF->getAlignment(), F);
295 if (MAI->hasDotTypeDotSizeDirective())
296 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
299 WriteAsOperand(OutStreamer.GetCommentOS(), F,
300 /*PrintType=*/false, F->getParent());
301 OutStreamer.GetCommentOS() << '\n';
304 // Emit the CurrentFnSym. This is is a virtual function to allow targets to
305 // do their wild and crazy things as required.
306 EmitFunctionEntryLabel();
308 // Add some workaround for linkonce linkage on Cygwin\MinGW.
309 if (MAI->getLinkOnceDirective() != 0 &&
310 (F->hasLinkOnceLinkage() || F->hasWeakLinkage()))
311 // FIXME: What is this?
312 O << "Lllvm$workaround$fake$stub$" << *CurrentFnSym << ":\n";
314 // Emit pre-function debug and/or EH information.
315 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
316 DW->BeginFunction(MF);
319 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
320 /// function. This can be overridden by targets as required to do custom stuff.
321 void AsmPrinter::EmitFunctionEntryLabel() {
322 OutStreamer.EmitLabel(CurrentFnSym);
326 /// EmitFunctionBody - This method emits the body and trailer for a
328 void AsmPrinter::EmitFunctionBody() {
329 // Emit target-specific gunk before the function body.
330 EmitFunctionBodyStart();
332 // Print out code for the function.
333 bool HasAnyRealCode = false;
334 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
336 // Print a label for the basic block.
337 EmitBasicBlockStart(I);
338 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
340 // Print the assembly for the instruction.
342 HasAnyRealCode = true;
346 // FIXME: Clean up processDebugLoc.
347 processDebugLoc(II, true);
349 switch (II->getOpcode()) {
350 case TargetInstrInfo::DBG_LABEL:
351 case TargetInstrInfo::EH_LABEL:
352 case TargetInstrInfo::GC_LABEL:
355 case TargetInstrInfo::INLINEASM:
358 case TargetInstrInfo::IMPLICIT_DEF:
359 printImplicitDef(II);
361 case TargetInstrInfo::KILL:
371 // FIXME: Clean up processDebugLoc.
372 processDebugLoc(II, false);
376 // If the function is empty and the object file uses .subsections_via_symbols,
377 // then we need to emit *something* to the function body to prevent the
378 // labels from collapsing together. Just emit a 0 byte.
379 if (MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)
380 OutStreamer.EmitIntValue(0, 1, 0/*addrspace*/);
382 // Emit target-specific gunk after the function body.
383 EmitFunctionBodyEnd();
385 if (MAI->hasDotTypeDotSizeDirective())
386 O << "\t.size\t" << *CurrentFnSym << ", .-" << *CurrentFnSym << '\n';
388 // Emit post-function debug information.
389 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
392 // Print out jump tables referenced by the function.
395 OutStreamer.AddBlankLine();
399 bool AsmPrinter::doFinalization(Module &M) {
400 // Emit global variables.
401 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
403 EmitGlobalVariable(I);
405 // Emit final debug information.
406 if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
409 // If the target wants to know about weak references, print them all.
410 if (MAI->getWeakRefDirective()) {
411 // FIXME: This is not lazy, it would be nice to only print weak references
412 // to stuff that is actually used. Note that doing so would require targets
413 // to notice uses in operands (due to constant exprs etc). This should
414 // happen with the MC stuff eventually.
416 // Print out module-level global variables here.
417 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
419 if (!I->hasExternalWeakLinkage()) continue;
420 OutStreamer.EmitSymbolAttribute(GetGlobalValueSymbol(I),
424 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
425 if (!I->hasExternalWeakLinkage()) continue;
426 OutStreamer.EmitSymbolAttribute(GetGlobalValueSymbol(I),
431 if (MAI->hasSetDirective()) {
432 OutStreamer.AddBlankLine();
433 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
435 MCSymbol *Name = GetGlobalValueSymbol(I);
437 const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
438 MCSymbol *Target = GetGlobalValueSymbol(GV);
440 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
441 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
442 else if (I->hasWeakLinkage())
443 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
445 assert(I->hasLocalLinkage() && "Invalid alias linkage");
447 EmitVisibility(Name, I->getVisibility());
449 // Emit the directives as assignments aka .set:
450 OutStreamer.EmitAssignment(Name,
451 MCSymbolRefExpr::Create(Target, OutContext));
455 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
456 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
457 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
458 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
459 MP->finishAssembly(O, *this, *MAI);
461 // If we don't have any trampolines, then we don't require stack memory
462 // to be executable. Some targets have a directive to declare this.
463 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
464 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
465 if (MCSection *S = MAI->getNonexecutableStackSection(OutContext))
466 OutStreamer.SwitchSection(S);
468 // Allow the target to emit any magic that it wants at the end of the file,
469 // after everything else has gone out.
472 delete Mang; Mang = 0;
475 OutStreamer.Finish();
479 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
481 // Get the function symbol.
482 CurrentFnSym = GetGlobalValueSymbol(MF.getFunction());
485 LI = &getAnalysis<MachineLoopInfo>();
489 // SectionCPs - Keep track the alignment, constpool entries per Section.
493 SmallVector<unsigned, 4> CPEs;
494 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
498 /// EmitConstantPool - Print to the current output stream assembly
499 /// representations of the constants in the constant pool MCP. This is
500 /// used to print out constants which have been "spilled to memory" by
501 /// the code generator.
503 void AsmPrinter::EmitConstantPool() {
504 const MachineConstantPool *MCP = MF->getConstantPool();
505 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
506 if (CP.empty()) return;
508 // Calculate sections for constant pool entries. We collect entries to go into
509 // the same section together to reduce amount of section switch statements.
510 SmallVector<SectionCPs, 4> CPSections;
511 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
512 const MachineConstantPoolEntry &CPE = CP[i];
513 unsigned Align = CPE.getAlignment();
516 switch (CPE.getRelocationInfo()) {
517 default: llvm_unreachable("Unknown section kind");
518 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
520 Kind = SectionKind::getReadOnlyWithRelLocal();
523 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
524 case 4: Kind = SectionKind::getMergeableConst4(); break;
525 case 8: Kind = SectionKind::getMergeableConst8(); break;
526 case 16: Kind = SectionKind::getMergeableConst16();break;
527 default: Kind = SectionKind::getMergeableConst(); break;
531 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
533 // The number of sections are small, just do a linear search from the
534 // last section to the first.
536 unsigned SecIdx = CPSections.size();
537 while (SecIdx != 0) {
538 if (CPSections[--SecIdx].S == S) {
544 SecIdx = CPSections.size();
545 CPSections.push_back(SectionCPs(S, Align));
548 if (Align > CPSections[SecIdx].Alignment)
549 CPSections[SecIdx].Alignment = Align;
550 CPSections[SecIdx].CPEs.push_back(i);
553 // Now print stuff into the calculated sections.
554 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
555 OutStreamer.SwitchSection(CPSections[i].S);
556 EmitAlignment(Log2_32(CPSections[i].Alignment));
559 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
560 unsigned CPI = CPSections[i].CPEs[j];
561 MachineConstantPoolEntry CPE = CP[CPI];
563 // Emit inter-object padding for alignment.
564 unsigned AlignMask = CPE.getAlignment() - 1;
565 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
566 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/);
568 const Type *Ty = CPE.getType();
569 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
571 // Emit the label with a comment on it.
573 OutStreamer.GetCommentOS() << "constant pool ";
574 WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(),
575 MF->getFunction()->getParent());
576 OutStreamer.GetCommentOS() << '\n';
578 OutStreamer.EmitLabel(GetCPISymbol(CPI));
580 if (CPE.isMachineConstantPoolEntry())
581 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
583 EmitGlobalConstant(CPE.Val.ConstVal);
588 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
589 /// by the current function to the current output stream.
591 void AsmPrinter::EmitJumpTableInfo() {
592 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
593 if (MJTI == 0) return;
594 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
595 if (JT.empty()) return;
597 // Pick the directive to use to print the jump table entries, and switch to
598 // the appropriate section.
599 const Function *F = MF->getFunction();
600 bool JTInDiffSection = false;
601 if (// In PIC mode, we need to emit the jump table to the same section as the
602 // function body itself, otherwise the label differences won't make sense.
603 // FIXME: Need a better predicate for this: what about custom entries?
604 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
605 // We should also do if the section name is NULL or function is declared
606 // in discardable section
607 // FIXME: this isn't the right predicate, should be based on the MCSection
609 F->isWeakForLinker()) {
610 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
612 // Otherwise, drop it in the readonly section.
613 const MCSection *ReadOnlySection =
614 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
615 OutStreamer.SwitchSection(ReadOnlySection);
616 JTInDiffSection = true;
619 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData())));
621 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
622 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
624 // If this jump table was deleted, ignore it.
625 if (JTBBs.empty()) continue;
627 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
628 // .set directive for each unique entry. This reduces the number of
629 // relocations the assembler will generate for the jump table.
630 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
631 MAI->hasSetDirective()) {
632 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
633 const TargetLowering *TLI = TM.getTargetLowering();
634 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
635 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
636 const MachineBasicBlock *MBB = JTBBs[ii];
637 if (!EmittedSets.insert(MBB)) continue;
639 // .set LJTSet, LBB32-base
641 MCSymbolRefExpr::Create(MBB->getSymbol(OutContext), OutContext);
642 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
643 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
647 // On some targets (e.g. Darwin) we want to emit two consequtive labels
648 // before each jump table. The first label is never referenced, but tells
649 // the assembler and linker the extents of the jump table object. The
650 // second label is actually referenced by the code.
651 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
652 // FIXME: This doesn't have to have any specific name, just any randomly
653 // named and numbered 'l' label would work. Simplify GetJTISymbol.
654 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
656 OutStreamer.EmitLabel(GetJTISymbol(JTI));
658 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
659 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
663 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
665 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
666 const MachineBasicBlock *MBB,
667 unsigned UID) const {
668 const MCExpr *Value = 0;
669 switch (MJTI->getEntryKind()) {
670 case MachineJumpTableInfo::EK_Custom32:
671 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
674 case MachineJumpTableInfo::EK_BlockAddress:
675 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
677 Value = MCSymbolRefExpr::Create(MBB->getSymbol(OutContext), OutContext);
679 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
680 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
681 // with a relocation as gp-relative, e.g.:
683 MCSymbol *MBBSym = MBB->getSymbol(OutContext);
684 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
688 case MachineJumpTableInfo::EK_LabelDifference32: {
689 // EK_LabelDifference32 - Each entry is the address of the block minus
690 // the address of the jump table. This is used for PIC jump tables where
691 // gprel32 is not supported. e.g.:
692 // .word LBB123 - LJTI1_2
693 // If the .set directive is supported, this is emitted as:
694 // .set L4_5_set_123, LBB123 - LJTI1_2
695 // .word L4_5_set_123
697 // If we have emitted set directives for the jump table entries, print
698 // them rather than the entries themselves. If we're emitting PIC, then
699 // emit the table entries as differences between two text section labels.
700 if (MAI->hasSetDirective()) {
701 // If we used .set, reference the .set's symbol.
702 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
706 // Otherwise, use the difference as the jump table entry.
707 Value = MCSymbolRefExpr::Create(MBB->getSymbol(OutContext), OutContext);
708 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
709 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
714 assert(Value && "Unknown entry kind!");
716 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData());
717 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0);
721 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
722 /// special global used by LLVM. If so, emit it and return true, otherwise
723 /// do nothing and return false.
724 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
725 if (GV->getName() == "llvm.used") {
726 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
727 EmitLLVMUsedList(GV->getInitializer());
731 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
732 if (GV->getSection() == "llvm.metadata" ||
733 GV->hasAvailableExternallyLinkage())
736 if (!GV->hasAppendingLinkage()) return false;
738 assert(GV->hasInitializer() && "Not a special LLVM global!");
740 const TargetData *TD = TM.getTargetData();
741 unsigned Align = Log2_32(TD->getPointerPrefAlignment());
742 if (GV->getName() == "llvm.global_ctors") {
743 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection());
744 EmitAlignment(Align, 0);
745 EmitXXStructorList(GV->getInitializer());
747 if (TM.getRelocationModel() == Reloc::Static &&
748 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
749 StringRef Sym(".constructors_used");
750 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
756 if (GV->getName() == "llvm.global_dtors") {
757 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection());
758 EmitAlignment(Align, 0);
759 EmitXXStructorList(GV->getInitializer());
761 if (TM.getRelocationModel() == Reloc::Static &&
762 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
763 StringRef Sym(".destructors_used");
764 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
773 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
774 /// global in the specified llvm.used list for which emitUsedDirectiveFor
775 /// is true, as being used with this directive.
776 void AsmPrinter::EmitLLVMUsedList(Constant *List) {
777 // Should be an array of 'i8*'.
778 ConstantArray *InitList = dyn_cast<ConstantArray>(List);
779 if (InitList == 0) return;
781 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
782 const GlobalValue *GV =
783 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
784 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
785 OutStreamer.EmitSymbolAttribute(GetGlobalValueSymbol(GV),
790 /// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the
791 /// function pointers, ignoring the init priority.
792 void AsmPrinter::EmitXXStructorList(Constant *List) {
793 // Should be an array of '{ int, void ()* }' structs. The first value is the
794 // init priority, which we ignore.
795 if (!isa<ConstantArray>(List)) return;
796 ConstantArray *InitList = cast<ConstantArray>(List);
797 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
798 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
799 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs.
801 if (CS->getOperand(1)->isNullValue())
802 return; // Found a null terminator, exit printing.
803 // Emit the function pointer.
804 EmitGlobalConstant(CS->getOperand(1));
808 //===--------------------------------------------------------------------===//
809 // Emission and print routines
812 /// EmitInt8 - Emit a byte directive and value.
814 void AsmPrinter::EmitInt8(int Value) const {
815 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/);
818 /// EmitInt16 - Emit a short directive and value.
820 void AsmPrinter::EmitInt16(int Value) const {
821 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/);
824 /// EmitInt32 - Emit a long directive and value.
826 void AsmPrinter::EmitInt32(int Value) const {
827 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/);
830 /// EmitInt64 - Emit a long long directive and value.
832 void AsmPrinter::EmitInt64(uint64_t Value) const {
833 OutStreamer.EmitIntValue(Value, 8, 0/*addrspace*/);
836 //===----------------------------------------------------------------------===//
838 // EmitAlignment - Emit an alignment directive to the specified power of
839 // two boundary. For example, if you pass in 3 here, you will get an 8
840 // byte alignment. If a global value is specified, and if that global has
841 // an explicit alignment requested, it will unconditionally override the
842 // alignment request. However, if ForcedAlignBits is specified, this value
843 // has final say: the ultimate alignment will be the max of ForcedAlignBits
844 // and the alignment computed with NumBits and the global.
848 // if (GV && GV->hasalignment) Align = GV->getalignment();
849 // Align = std::max(Align, ForcedAlignBits);
851 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
852 unsigned ForcedAlignBits,
853 bool UseFillExpr) const {
854 if (GV && GV->getAlignment())
855 NumBits = Log2_32(GV->getAlignment());
856 NumBits = std::max(NumBits, ForcedAlignBits);
858 if (NumBits == 0) return; // No need to emit alignment.
860 unsigned FillValue = 0;
861 if (getCurrentSection()->getKind().isText())
862 FillValue = MAI->getTextAlignFillValue();
864 OutStreamer.EmitValueToAlignment(1 << NumBits, FillValue, 1, 0);
867 /// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
869 static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) {
870 MCContext &Ctx = AP.OutContext;
872 if (CV->isNullValue() || isa<UndefValue>(CV))
873 return MCConstantExpr::Create(0, Ctx);
875 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
876 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
878 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
879 return MCSymbolRefExpr::Create(AP.GetGlobalValueSymbol(GV), Ctx);
880 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
881 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
883 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
885 llvm_unreachable("Unknown constant value to lower!");
886 return MCConstantExpr::Create(0, Ctx);
889 switch (CE->getOpcode()) {
890 case Instruction::ZExt:
891 case Instruction::SExt:
892 case Instruction::FPTrunc:
893 case Instruction::FPExt:
894 case Instruction::UIToFP:
895 case Instruction::SIToFP:
896 case Instruction::FPToUI:
897 case Instruction::FPToSI:
898 default: llvm_unreachable("FIXME: Don't support this constant cast expr");
899 case Instruction::GetElementPtr: {
900 const TargetData &TD = *AP.TM.getTargetData();
901 // Generate a symbolic expression for the byte address
902 const Constant *PtrVal = CE->getOperand(0);
903 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
904 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0],
907 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
911 // Truncate/sext the offset to the pointer size.
912 if (TD.getPointerSizeInBits() != 64) {
913 int SExtAmount = 64-TD.getPointerSizeInBits();
914 Offset = (Offset << SExtAmount) >> SExtAmount;
917 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
921 case Instruction::Trunc:
922 // We emit the value and depend on the assembler to truncate the generated
923 // expression properly. This is important for differences between
924 // blockaddress labels. Since the two labels are in the same function, it
925 // is reasonable to treat their delta as a 32-bit value.
927 case Instruction::BitCast:
928 return LowerConstant(CE->getOperand(0), AP);
930 case Instruction::IntToPtr: {
931 const TargetData &TD = *AP.TM.getTargetData();
932 // Handle casts to pointers by changing them into casts to the appropriate
933 // integer type. This promotes constant folding and simplifies this code.
934 Constant *Op = CE->getOperand(0);
935 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
937 return LowerConstant(Op, AP);
940 case Instruction::PtrToInt: {
941 const TargetData &TD = *AP.TM.getTargetData();
942 // Support only foldable casts to/from pointers that can be eliminated by
943 // changing the pointer to the appropriately sized integer type.
944 Constant *Op = CE->getOperand(0);
945 const Type *Ty = CE->getType();
947 const MCExpr *OpExpr = LowerConstant(Op, AP);
949 // We can emit the pointer value into this slot if the slot is an
950 // integer slot equal to the size of the pointer.
951 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
954 // Otherwise the pointer is smaller than the resultant integer, mask off
955 // the high bits so we are sure to get a proper truncation if the input is
957 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
958 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
959 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
962 case Instruction::Add:
963 case Instruction::Sub:
964 case Instruction::And:
965 case Instruction::Or:
966 case Instruction::Xor: {
967 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP);
968 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP);
969 switch (CE->getOpcode()) {
970 default: llvm_unreachable("Unknown binary operator constant cast expr");
971 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
972 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
973 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
974 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
975 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
981 static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
983 if (AddrSpace != 0 || !CA->isString()) {
984 // Not a string. Print the values in successive locations
985 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
986 AP.EmitGlobalConstant(CA->getOperand(i), AddrSpace);
990 // Otherwise, it can be emitted as .ascii.
991 SmallVector<char, 128> TmpVec;
992 TmpVec.reserve(CA->getNumOperands());
993 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
994 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
996 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace);
999 static void EmitGlobalConstantVector(const ConstantVector *CV,
1000 unsigned AddrSpace, AsmPrinter &AP) {
1001 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1002 AP.EmitGlobalConstant(CV->getOperand(i), AddrSpace);
1005 static void EmitGlobalConstantStruct(const ConstantStruct *CS,
1006 unsigned AddrSpace, AsmPrinter &AP) {
1007 // Print the fields in successive locations. Pad to align if needed!
1008 const TargetData *TD = AP.TM.getTargetData();
1009 unsigned Size = TD->getTypeAllocSize(CS->getType());
1010 const StructLayout *Layout = TD->getStructLayout(CS->getType());
1011 uint64_t SizeSoFar = 0;
1012 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1013 const Constant *Field = CS->getOperand(i);
1015 // Check if padding is needed and insert one or more 0s.
1016 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
1017 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1018 - Layout->getElementOffset(i)) - FieldSize;
1019 SizeSoFar += FieldSize + PadSize;
1021 // Now print the actual field value.
1022 AP.EmitGlobalConstant(Field, AddrSpace);
1024 // Insert padding - this may include padding to increase the size of the
1025 // current field up to the ABI size (if the struct is not packed) as well
1026 // as padding to ensure that the next field starts at the right offset.
1027 AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
1029 assert(SizeSoFar == Layout->getSizeInBytes() &&
1030 "Layout of constant struct may be incorrect!");
1033 static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
1035 // FP Constants are printed as integer constants to avoid losing
1037 if (CFP->getType()->isDoubleTy()) {
1038 if (AP.VerboseAsm) {
1039 double Val = CFP->getValueAPF().convertToDouble();
1040 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n';
1043 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1044 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1048 if (CFP->getType()->isFloatTy()) {
1049 if (AP.VerboseAsm) {
1050 float Val = CFP->getValueAPF().convertToFloat();
1051 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n';
1053 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1054 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace);
1058 if (CFP->getType()->isX86_FP80Ty()) {
1059 // all long double variants are printed as hex
1060 // api needed to prevent premature destruction
1061 APInt API = CFP->getValueAPF().bitcastToAPInt();
1062 const uint64_t *p = API.getRawData();
1063 if (AP.VerboseAsm) {
1064 // Convert to double so we can print the approximate val as a comment.
1065 APFloat DoubleVal = CFP->getValueAPF();
1067 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1069 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= "
1070 << DoubleVal.convertToDouble() << '\n';
1073 if (AP.TM.getTargetData()->isBigEndian()) {
1074 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1075 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1077 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1078 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1081 // Emit the tail padding for the long double.
1082 const TargetData &TD = *AP.TM.getTargetData();
1083 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
1084 TD.getTypeStoreSize(CFP->getType()), AddrSpace);
1088 assert(CFP->getType()->isPPC_FP128Ty() &&
1089 "Floating point constant type not handled");
1090 // All long double variants are printed as hex api needed to prevent
1091 // premature destruction.
1092 APInt API = CFP->getValueAPF().bitcastToAPInt();
1093 const uint64_t *p = API.getRawData();
1094 if (AP.TM.getTargetData()->isBigEndian()) {
1095 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1096 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1098 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1099 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1103 static void EmitGlobalConstantLargeInt(const ConstantInt *CI,
1104 unsigned AddrSpace, AsmPrinter &AP) {
1105 const TargetData *TD = AP.TM.getTargetData();
1106 unsigned BitWidth = CI->getBitWidth();
1107 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
1109 // We don't expect assemblers to support integer data directives
1110 // for more than 64 bits, so we emit the data in at most 64-bit
1111 // quantities at a time.
1112 const uint64_t *RawData = CI->getValue().getRawData();
1113 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1114 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1115 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1119 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1120 void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1121 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) {
1122 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1123 return OutStreamer.EmitZeros(Size, AddrSpace);
1126 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1127 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1134 OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue());
1135 OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1138 EmitGlobalConstantLargeInt(CI, AddrSpace, *this);
1143 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1144 return EmitGlobalConstantArray(CVA, AddrSpace, *this);
1146 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1147 return EmitGlobalConstantStruct(CVS, AddrSpace, *this);
1149 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1150 return EmitGlobalConstantFP(CFP, AddrSpace, *this);
1152 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1153 return EmitGlobalConstantVector(V, AddrSpace, *this);
1155 if (isa<ConstantPointerNull>(CV)) {
1156 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1157 OutStreamer.EmitIntValue(0, Size, AddrSpace);
1161 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1162 // thread the streamer with EmitValue.
1163 OutStreamer.EmitValue(LowerConstant(CV, *this),
1164 TM.getTargetData()->getTypeAllocSize(CV->getType()),
1168 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1169 // Target doesn't support this yet!
1170 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1173 /// PrintSpecial - Print information related to the specified machine instr
1174 /// that is independent of the operand, and may be independent of the instr
1175 /// itself. This can be useful for portably encoding the comment character
1176 /// or other bits of target-specific knowledge into the asmstrings. The
1177 /// syntax used is ${:comment}. Targets can override this to add support
1178 /// for their own strange codes.
1179 void AsmPrinter::PrintSpecial(const MachineInstr *MI, const char *Code) const {
1180 if (!strcmp(Code, "private")) {
1181 O << MAI->getPrivateGlobalPrefix();
1182 } else if (!strcmp(Code, "comment")) {
1184 O << MAI->getCommentString();
1185 } else if (!strcmp(Code, "uid")) {
1186 // Comparing the address of MI isn't sufficient, because machineinstrs may
1187 // be allocated to the same address across functions.
1188 const Function *ThisF = MI->getParent()->getParent()->getFunction();
1190 // If this is a new LastFn instruction, bump the counter.
1191 if (LastMI != MI || LastFn != ThisF) {
1199 raw_string_ostream Msg(msg);
1200 Msg << "Unknown special formatter '" << Code
1201 << "' for machine instr: " << *MI;
1202 llvm_report_error(Msg.str());
1206 /// processDebugLoc - Processes the debug information of each machine
1207 /// instruction's DebugLoc.
1208 void AsmPrinter::processDebugLoc(const MachineInstr *MI,
1209 bool BeforePrintingInsn) {
1210 if (!MAI || !DW || !MAI->doesSupportDebugInformation()
1211 || !DW->ShouldEmitDwarfDebug())
1213 DebugLoc DL = MI->getDebugLoc();
1216 DILocation CurDLT = MF->getDILocation(DL);
1217 if (CurDLT.getScope().isNull())
1220 if (!BeforePrintingInsn) {
1221 // After printing instruction
1223 } else if (CurDLT.getNode() != PrevDLT) {
1224 unsigned L = DW->RecordSourceLine(CurDLT.getLineNumber(),
1225 CurDLT.getColumnNumber(),
1226 CurDLT.getScope().getNode());
1229 DW->BeginScope(MI, L);
1230 PrevDLT = CurDLT.getNode();
1235 /// printInlineAsm - This method formats and prints the specified machine
1236 /// instruction that is an inline asm.
1237 void AsmPrinter::printInlineAsm(const MachineInstr *MI) const {
1238 unsigned NumOperands = MI->getNumOperands();
1240 // Count the number of register definitions.
1241 unsigned NumDefs = 0;
1242 for (; MI->getOperand(NumDefs).isReg() && MI->getOperand(NumDefs).isDef();
1244 assert(NumDefs != NumOperands-1 && "No asm string?");
1246 assert(MI->getOperand(NumDefs).isSymbol() && "No asm string?");
1248 // Disassemble the AsmStr, printing out the literal pieces, the operands, etc.
1249 const char *AsmStr = MI->getOperand(NumDefs).getSymbolName();
1253 // If this asmstr is empty, just print the #APP/#NOAPP markers.
1254 // These are useful to see where empty asm's wound up.
1255 if (AsmStr[0] == 0) {
1256 O << MAI->getCommentString() << MAI->getInlineAsmStart() << "\n\t";
1257 O << MAI->getCommentString() << MAI->getInlineAsmEnd() << '\n';
1261 O << MAI->getCommentString() << MAI->getInlineAsmStart() << "\n\t";
1263 // The variant of the current asmprinter.
1264 int AsmPrinterVariant = MAI->getAssemblerDialect();
1266 int CurVariant = -1; // The number of the {.|.|.} region we are in.
1267 const char *LastEmitted = AsmStr; // One past the last character emitted.
1269 while (*LastEmitted) {
1270 switch (*LastEmitted) {
1272 // Not a special case, emit the string section literally.
1273 const char *LiteralEnd = LastEmitted+1;
1274 while (*LiteralEnd && *LiteralEnd != '{' && *LiteralEnd != '|' &&
1275 *LiteralEnd != '}' && *LiteralEnd != '$' && *LiteralEnd != '\n')
1277 if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1278 O.write(LastEmitted, LiteralEnd-LastEmitted);
1279 LastEmitted = LiteralEnd;
1283 ++LastEmitted; // Consume newline character.
1284 O << '\n'; // Indent code with newline.
1287 ++LastEmitted; // Consume '$' character.
1291 switch (*LastEmitted) {
1292 default: Done = false; break;
1293 case '$': // $$ -> $
1294 if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1296 ++LastEmitted; // Consume second '$' character.
1298 case '(': // $( -> same as GCC's { character.
1299 ++LastEmitted; // Consume '(' character.
1300 if (CurVariant != -1) {
1301 llvm_report_error("Nested variants found in inline asm string: '"
1302 + std::string(AsmStr) + "'");
1304 CurVariant = 0; // We're in the first variant now.
1307 ++LastEmitted; // consume '|' character.
1308 if (CurVariant == -1)
1309 O << '|'; // this is gcc's behavior for | outside a variant
1311 ++CurVariant; // We're in the next variant.
1313 case ')': // $) -> same as GCC's } char.
1314 ++LastEmitted; // consume ')' character.
1315 if (CurVariant == -1)
1316 O << '}'; // this is gcc's behavior for } outside a variant
1323 bool HasCurlyBraces = false;
1324 if (*LastEmitted == '{') { // ${variable}
1325 ++LastEmitted; // Consume '{' character.
1326 HasCurlyBraces = true;
1329 // If we have ${:foo}, then this is not a real operand reference, it is a
1330 // "magic" string reference, just like in .td files. Arrange to call
1332 if (HasCurlyBraces && *LastEmitted == ':') {
1334 const char *StrStart = LastEmitted;
1335 const char *StrEnd = strchr(StrStart, '}');
1337 llvm_report_error("Unterminated ${:foo} operand in inline asm string: '"
1338 + std::string(AsmStr) + "'");
1341 std::string Val(StrStart, StrEnd);
1342 PrintSpecial(MI, Val.c_str());
1343 LastEmitted = StrEnd+1;
1347 const char *IDStart = LastEmitted;
1350 long Val = strtol(IDStart, &IDEnd, 10); // We only accept numbers for IDs.
1351 if (!isdigit(*IDStart) || (Val == 0 && errno == EINVAL)) {
1352 llvm_report_error("Bad $ operand number in inline asm string: '"
1353 + std::string(AsmStr) + "'");
1355 LastEmitted = IDEnd;
1357 char Modifier[2] = { 0, 0 };
1359 if (HasCurlyBraces) {
1360 // If we have curly braces, check for a modifier character. This
1361 // supports syntax like ${0:u}, which correspond to "%u0" in GCC asm.
1362 if (*LastEmitted == ':') {
1363 ++LastEmitted; // Consume ':' character.
1364 if (*LastEmitted == 0) {
1365 llvm_report_error("Bad ${:} expression in inline asm string: '"
1366 + std::string(AsmStr) + "'");
1369 Modifier[0] = *LastEmitted;
1370 ++LastEmitted; // Consume modifier character.
1373 if (*LastEmitted != '}') {
1374 llvm_report_error("Bad ${} expression in inline asm string: '"
1375 + std::string(AsmStr) + "'");
1377 ++LastEmitted; // Consume '}' character.
1380 if ((unsigned)Val >= NumOperands-1) {
1381 llvm_report_error("Invalid $ operand number in inline asm string: '"
1382 + std::string(AsmStr) + "'");
1385 // Okay, we finally have a value number. Ask the target to print this
1387 if (CurVariant == -1 || CurVariant == AsmPrinterVariant) {
1392 // Scan to find the machine operand number for the operand.
1393 for (; Val; --Val) {
1394 if (OpNo >= MI->getNumOperands()) break;
1395 unsigned OpFlags = MI->getOperand(OpNo).getImm();
1396 OpNo += InlineAsm::getNumOperandRegisters(OpFlags) + 1;
1399 if (OpNo >= MI->getNumOperands()) {
1402 unsigned OpFlags = MI->getOperand(OpNo).getImm();
1403 ++OpNo; // Skip over the ID number.
1405 if (Modifier[0] == 'l') // labels are target independent
1406 O << *MI->getOperand(OpNo).getMBB()->getSymbol(OutContext);
1408 AsmPrinter *AP = const_cast<AsmPrinter*>(this);
1409 if ((OpFlags & 7) == 4) {
1410 Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant,
1411 Modifier[0] ? Modifier : 0);
1413 Error = AP->PrintAsmOperand(MI, OpNo, AsmPrinterVariant,
1414 Modifier[0] ? Modifier : 0);
1420 raw_string_ostream Msg(msg);
1421 Msg << "Invalid operand found in inline asm: '" << AsmStr << "'\n";
1423 llvm_report_error(Msg.str());
1430 O << "\n\t" << MAI->getCommentString() << MAI->getInlineAsmEnd() << '\n';
1433 /// printImplicitDef - This method prints the specified machine instruction
1434 /// that is an implicit def.
1435 void AsmPrinter::printImplicitDef(const MachineInstr *MI) const {
1436 if (!VerboseAsm) return;
1437 O.PadToColumn(MAI->getCommentColumn());
1438 O << MAI->getCommentString() << " implicit-def: "
1439 << TRI->getName(MI->getOperand(0).getReg()) << '\n';
1442 void AsmPrinter::printKill(const MachineInstr *MI) const {
1443 if (!VerboseAsm) return;
1444 O.PadToColumn(MAI->getCommentColumn());
1445 O << MAI->getCommentString() << " kill:";
1446 for (unsigned n = 0, e = MI->getNumOperands(); n != e; ++n) {
1447 const MachineOperand &op = MI->getOperand(n);
1448 assert(op.isReg() && "KILL instruction must have only register operands");
1449 O << ' ' << TRI->getName(op.getReg()) << (op.isDef() ? "<def>" : "<kill>");
1454 /// printLabel - This method prints a local label used by debug and
1455 /// exception handling tables.
1456 void AsmPrinter::printLabelInst(const MachineInstr *MI) const {
1457 printLabel(MI->getOperand(0).getImm());
1461 void AsmPrinter::printLabel(unsigned Id) const {
1462 O << MAI->getPrivateGlobalPrefix() << "label" << Id << ':';
1465 /// PrintAsmOperand - Print the specified operand of MI, an INLINEASM
1466 /// instruction, using the specified assembler variant. Targets should
1467 /// override this to format as appropriate.
1468 bool AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
1469 unsigned AsmVariant, const char *ExtraCode) {
1470 // Target doesn't support this yet!
1474 bool AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
1475 unsigned AsmVariant,
1476 const char *ExtraCode) {
1477 // Target doesn't support this yet!
1481 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA,
1482 const char *Suffix) const {
1483 return GetBlockAddressSymbol(BA->getFunction(), BA->getBasicBlock(), Suffix);
1486 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const Function *F,
1487 const BasicBlock *BB,
1488 const char *Suffix) const {
1489 assert(BB->hasName() &&
1490 "Address of anonymous basic block not supported yet!");
1492 // This code must use the function name itself, and not the function number,
1493 // since it must be possible to generate the label name from within other
1495 SmallString<60> FnName;
1496 Mang->getNameWithPrefix(FnName, F, false);
1498 // FIXME: THIS IS BROKEN IF THE LLVM BASIC BLOCK DOESN'T HAVE A NAME!
1499 SmallString<60> NameResult;
1500 Mang->getNameWithPrefix(NameResult,
1501 StringRef("BA") + Twine((unsigned)FnName.size()) +
1502 "_" + FnName.str() + "_" + BB->getName() + Suffix,
1505 return OutContext.GetOrCreateSymbol(NameResult.str());
1508 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1509 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1510 SmallString<60> Name;
1511 raw_svector_ostream(Name) << MAI->getPrivateGlobalPrefix() << "CPI"
1512 << getFunctionNumber() << '_' << CPID;
1513 return OutContext.GetOrCreateSymbol(Name.str());
1516 /// GetJTISymbol - Return the symbol for the specified jump table entry.
1517 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1518 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
1521 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
1522 /// FIXME: privatize to AsmPrinter.
1523 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
1524 SmallString<60> Name;
1525 raw_svector_ostream(Name) << MAI->getPrivateGlobalPrefix()
1526 << getFunctionNumber() << '_' << UID << "_set_" << MBBID;
1527 return OutContext.GetOrCreateSymbol(Name.str());
1530 /// GetGlobalValueSymbol - Return the MCSymbol for the specified global
1532 MCSymbol *AsmPrinter::GetGlobalValueSymbol(const GlobalValue *GV) const {
1533 SmallString<60> NameStr;
1534 Mang->getNameWithPrefix(NameStr, GV, false);
1535 return OutContext.GetOrCreateSymbol(NameStr.str());
1538 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1539 /// global value name as its base, with the specified suffix, and where the
1540 /// symbol is forced to have private linkage if ForcePrivate is true.
1541 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1543 bool ForcePrivate) const {
1544 SmallString<60> NameStr;
1545 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1546 NameStr.append(Suffix.begin(), Suffix.end());
1547 return OutContext.GetOrCreateSymbol(NameStr.str());
1550 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
1552 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
1553 SmallString<60> NameStr;
1554 Mang->getNameWithPrefix(NameStr, Sym);
1555 return OutContext.GetOrCreateSymbol(NameStr.str());
1560 /// PrintParentLoopComment - Print comments about parent loops of this one.
1561 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1562 unsigned FunctionNumber) {
1563 if (Loop == 0) return;
1564 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
1565 OS.indent(Loop->getLoopDepth()*2)
1566 << "Parent Loop BB" << FunctionNumber << "_"
1567 << Loop->getHeader()->getNumber()
1568 << " Depth=" << Loop->getLoopDepth() << '\n';
1572 /// PrintChildLoopComment - Print comments about child loops within
1573 /// the loop for this basic block, with nesting.
1574 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1575 unsigned FunctionNumber) {
1576 // Add child loop information
1577 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
1578 OS.indent((*CL)->getLoopDepth()*2)
1579 << "Child Loop BB" << FunctionNumber << "_"
1580 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
1582 PrintChildLoopComment(OS, *CL, FunctionNumber);
1586 /// PrintBasicBlockLoopComments - Pretty-print comments for basic blocks.
1587 static void PrintBasicBlockLoopComments(const MachineBasicBlock &MBB,
1588 const MachineLoopInfo *LI,
1589 const AsmPrinter &AP) {
1590 // Add loop depth information
1591 const MachineLoop *Loop = LI->getLoopFor(&MBB);
1592 if (Loop == 0) return;
1594 MachineBasicBlock *Header = Loop->getHeader();
1595 assert(Header && "No header for loop");
1597 // If this block is not a loop header, just print out what is the loop header
1599 if (Header != &MBB) {
1600 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
1601 Twine(AP.getFunctionNumber())+"_" +
1602 Twine(Loop->getHeader()->getNumber())+
1603 " Depth="+Twine(Loop->getLoopDepth()));
1607 // Otherwise, it is a loop header. Print out information about child and
1609 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
1611 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
1614 OS.indent(Loop->getLoopDepth()*2-2);
1619 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
1621 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
1625 /// EmitBasicBlockStart - This method prints the label for the specified
1626 /// MachineBasicBlock, an alignment (if present) and a comment describing
1627 /// it if appropriate.
1628 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
1629 // Emit an alignment directive for this block, if needed.
1630 if (unsigned Align = MBB->getAlignment())
1631 EmitAlignment(Log2_32(Align));
1633 // If the block has its address taken, emit a special label to satisfy
1634 // references to the block. This is done so that we don't need to
1635 // remember the number of this label, and so that we can make
1636 // forward references to labels without knowing what their numbers
1638 if (MBB->hasAddressTaken()) {
1639 const BasicBlock *BB = MBB->getBasicBlock();
1641 OutStreamer.AddComment("Address Taken");
1642 OutStreamer.EmitLabel(GetBlockAddressSymbol(BB->getParent(), BB));
1645 // Print the main label for the block.
1646 if (MBB->pred_empty() || MBB->isOnlyReachableByFallthrough()) {
1648 // NOTE: Want this comment at start of line.
1649 O << MAI->getCommentString() << " BB#" << MBB->getNumber() << ':';
1650 if (const BasicBlock *BB = MBB->getBasicBlock())
1652 OutStreamer.AddComment("%" + BB->getName());
1654 PrintBasicBlockLoopComments(*MBB, LI, *this);
1655 OutStreamer.AddBlankLine();
1659 if (const BasicBlock *BB = MBB->getBasicBlock())
1661 OutStreamer.AddComment("%" + BB->getName());
1662 PrintBasicBlockLoopComments(*MBB, LI, *this);
1665 OutStreamer.EmitLabel(MBB->getSymbol(OutContext));
1669 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility) const {
1670 MCSymbolAttr Attr = MCSA_Invalid;
1672 switch (Visibility) {
1674 case GlobalValue::HiddenVisibility:
1675 Attr = MAI->getHiddenVisibilityAttr();
1677 case GlobalValue::ProtectedVisibility:
1678 Attr = MAI->getProtectedVisibilityAttr();
1682 if (Attr != MCSA_Invalid)
1683 OutStreamer.EmitSymbolAttribute(Sym, Attr);
1686 void AsmPrinter::printOffset(int64_t Offset) const {
1689 else if (Offset < 0)
1693 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1694 if (!S->usesMetadata())
1697 gcp_iterator GCPI = GCMetadataPrinters.find(S);
1698 if (GCPI != GCMetadataPrinters.end())
1699 return GCPI->second;
1701 const char *Name = S->getName().c_str();
1703 for (GCMetadataPrinterRegistry::iterator
1704 I = GCMetadataPrinterRegistry::begin(),
1705 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1706 if (strcmp(Name, I->getName()) == 0) {
1707 GCMetadataPrinter *GMP = I->instantiate();
1709 GCMetadataPrinters.insert(std::make_pair(S, GMP));
1713 llvm_report_error("no GCMetadataPrinter registered for GC: " + Twine(Name));
1717 /// EmitComments - Pretty-print comments for instructions
1718 void AsmPrinter::EmitComments(const MachineInstr &MI) const {
1722 if (!MI.getDebugLoc().isUnknown()) {
1723 DILocation DLT = MF->getDILocation(MI.getDebugLoc());
1725 // Print source line info.
1726 O.PadToColumn(MAI->getCommentColumn());
1727 O << MAI->getCommentString() << ' ';
1728 DIScope Scope = DLT.getScope();
1729 // Omit the directory, because it's likely to be long and uninteresting.
1730 if (!Scope.isNull())
1731 O << Scope.getFilename();
1734 O << ':' << DLT.getLineNumber();
1735 if (DLT.getColumnNumber() != 0)
1736 O << ':' << DLT.getColumnNumber();
1740 // Check for spills and reloads
1743 const MachineFrameInfo *FrameInfo =
1744 MI.getParent()->getParent()->getFrameInfo();
1746 // We assume a single instruction only has a spill or reload, not
1748 const MachineMemOperand *MMO;
1749 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
1750 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
1751 MMO = *MI.memoperands_begin();
1752 O.PadToColumn(MAI->getCommentColumn());
1753 O << MAI->getCommentString() << ' ' << MMO->getSize() << "-byte Reload\n";
1756 else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
1757 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
1758 O.PadToColumn(MAI->getCommentColumn());
1759 O << MAI->getCommentString() << ' '
1760 << MMO->getSize() << "-byte Folded Reload\n";
1763 else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
1764 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
1765 MMO = *MI.memoperands_begin();
1766 O.PadToColumn(MAI->getCommentColumn());
1767 O << MAI->getCommentString() << ' ' << MMO->getSize() << "-byte Spill\n";
1770 else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
1771 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
1772 O.PadToColumn(MAI->getCommentColumn());
1773 O << MAI->getCommentString() << ' '
1774 << MMO->getSize() << "-byte Folded Spill\n";
1778 // Check for spill-induced copies
1779 unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
1780 if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg,
1781 SrcSubIdx, DstSubIdx)) {
1782 if (MI.getAsmPrinterFlag(ReloadReuse)) {
1783 O.PadToColumn(MAI->getCommentColumn());
1784 O << MAI->getCommentString() << " Reload Reuse\n";