AsmPrinter.cpp revision e13c8ac5306fa2d2069f0defa932adf6aa3355bb 
1//===-- AsmPrinter.cpp - Common AsmPrinter code ---------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file implements the AsmPrinter class.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/CodeGen/AsmPrinter.h"
15#include "llvm/Assembly/Writer.h"
16#include "llvm/DerivedTypes.h"
17#include "llvm/Constants.h"
18#include "llvm/Module.h"
19#include "llvm/CodeGen/DwarfWriter.h"
20#include "llvm/CodeGen/GCMetadataPrinter.h"
21#include "llvm/CodeGen/MachineConstantPool.h"
22#include "llvm/CodeGen/MachineFrameInfo.h"
23#include "llvm/CodeGen/MachineFunction.h"
24#include "llvm/CodeGen/MachineJumpTableInfo.h"
25#include "llvm/CodeGen/MachineLoopInfo.h"
26#include "llvm/CodeGen/MachineModuleInfo.h"
27#include "llvm/Analysis/DebugInfo.h"
28#include "llvm/MC/MCContext.h"
29#include "llvm/MC/MCExpr.h"
30#include "llvm/MC/MCInst.h"
31#include "llvm/MC/MCSection.h"
32#include "llvm/MC/MCStreamer.h"
33#include "llvm/MC/MCSymbol.h"
34#include "llvm/Support/CommandLine.h"
35#include "llvm/Support/ErrorHandling.h"
36#include "llvm/Support/Format.h"
37#include "llvm/Support/FormattedStream.h"
38#include "llvm/MC/MCAsmInfo.h"
39#include "llvm/Target/Mangler.h"
40#include "llvm/Target/TargetData.h"
41#include "llvm/Target/TargetInstrInfo.h"
42#include "llvm/Target/TargetLowering.h"
43#include "llvm/Target/TargetLoweringObjectFile.h"
44#include "llvm/Target/TargetOptions.h"
45#include "llvm/Target/TargetRegisterInfo.h"
46#include "llvm/ADT/SmallPtrSet.h"
47#include "llvm/ADT/SmallString.h"
48#include <cerrno>
49using namespace llvm;
50
51static cl::opt<cl::boolOrDefault>
52AsmVerbose("asm-verbose", cl::desc("Add comments to directives."),
53           cl::init(cl::BOU_UNSET));
54
55static bool getVerboseAsm(bool VDef) {
56  switch (AsmVerbose) {
57  default:
58  case cl::BOU_UNSET: return VDef;
59  case cl::BOU_TRUE:  return true;
60  case cl::BOU_FALSE: return false;
61  }
62}
63
64char AsmPrinter::ID = 0;
65AsmPrinter::AsmPrinter(formatted_raw_ostream &o, TargetMachine &tm,
66                       const MCAsmInfo *T, bool VDef)
67  : MachineFunctionPass(&ID), FunctionNumber(0), O(o),
68    TM(tm), MAI(T), TRI(tm.getRegisterInfo()),
69
70    OutContext(*new MCContext()),
71    // FIXME: Pass instprinter to streamer.
72    OutStreamer(*createAsmStreamer(OutContext, O, *T,
73                                   TM.getTargetData()->isLittleEndian(),
74                                   getVerboseAsm(VDef), 0)),
75
76    LastMI(0), LastFn(0), Counter(~0U), PrevDLT(NULL) {
77  DW = 0; MMI = 0;
78  VerboseAsm = getVerboseAsm(VDef);
79}
80
81AsmPrinter::~AsmPrinter() {
82  for (gcp_iterator I = GCMetadataPrinters.begin(),
83                    E = GCMetadataPrinters.end(); I != E; ++I)
84    delete I->second;
85
86  delete &OutStreamer;
87  delete &OutContext;
88}
89
90TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
91  return TM.getTargetLowering()->getObjFileLowering();
92}
93
94/// getCurrentSection() - Return the current section we are emitting to.
95const MCSection *AsmPrinter::getCurrentSection() const {
96  return OutStreamer.getCurrentSection();
97}
98
99
100void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
101  AU.setPreservesAll();
102  MachineFunctionPass::getAnalysisUsage(AU);
103  AU.addRequired<GCModuleInfo>();
104  if (VerboseAsm)
105    AU.addRequired<MachineLoopInfo>();
106}
107
108bool AsmPrinter::doInitialization(Module &M) {
109  // Initialize TargetLoweringObjectFile.
110  const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
111    .Initialize(OutContext, TM);
112
113  Mang = new Mangler(*MAI);
114
115  // Allow the target to emit any magic that it wants at the start of the file.
116  EmitStartOfAsmFile(M);
117
118  if (MAI->hasSingleParameterDotFile()) {
119    // Very minimal debug info. It is ignored if we emit actual
120    // debug info. If we don't, this at least helps the user find where
121    // a function came from.
122    O << "\t.file\t\"" << M.getModuleIdentifier() << "\"\n";
123  }
124
125  GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
126  assert(MI && "AsmPrinter didn't require GCModuleInfo?");
127  for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
128    if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
129      MP->beginAssembly(O, *this, *MAI);
130
131  if (!M.getModuleInlineAsm().empty())
132    O << MAI->getCommentString() << " Start of file scope inline assembly\n"
133      << M.getModuleInlineAsm()
134      << '\n' << MAI->getCommentString()
135      << " End of file scope inline assembly\n";
136
137  MMI = getAnalysisIfAvailable<MachineModuleInfo>();
138  if (MMI)
139    MMI->AnalyzeModule(M);
140  DW = getAnalysisIfAvailable<DwarfWriter>();
141  if (DW)
142    DW->BeginModule(&M, MMI, O, this, MAI);
143
144  return false;
145}
146
147/// EmitGlobalVariable - Emit the specified global variable to the .s file.
148void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
149  if (!GV->hasInitializer())   // External globals require no code.
150    return;
151
152  // Check to see if this is a special global used by LLVM, if so, emit it.
153  if (EmitSpecialLLVMGlobal(GV))
154    return;
155
156  MCSymbol *GVSym = GetGlobalValueSymbol(GV);
157  printVisibility(GVSym, GV->getVisibility());
158
159  if (MAI->hasDotTypeDotSizeDirective()) {
160    O << "\t.type\t" << *GVSym;
161    if (MAI->getCommentString()[0] != '@')
162      O << ",@object\n";
163    else
164      O << ",%object\n";
165  }
166
167  SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
168
169  const TargetData *TD = TM.getTargetData();
170  unsigned Size = TD->getTypeAllocSize(GV->getType()->getElementType());
171  unsigned AlignLog = TD->getPreferredAlignmentLog(GV);
172
173  // Handle common and BSS local symbols (.lcomm).
174  if (GVKind.isCommon() || GVKind.isBSSLocal()) {
175    if (Size == 0) Size = 1;   // .comm Foo, 0 is undefined, avoid it.
176
177    if (VerboseAsm) {
178      WriteAsOperand(OutStreamer.GetCommentOS(), GV,
179                     /*PrintType=*/false, GV->getParent());
180      OutStreamer.GetCommentOS() << '\n';
181    }
182
183    // Handle common symbols.
184    if (GVKind.isCommon()) {
185      // .comm _foo, 42, 4
186      OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
187      return;
188    }
189
190    // Handle local BSS symbols.
191    if (MAI->hasMachoZeroFillDirective()) {
192      const MCSection *TheSection =
193        getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
194      // .zerofill __DATA, __bss, _foo, 400, 5
195      OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
196      return;
197    }
198
199    if (MAI->hasLCOMMDirective()) {
200      // .lcomm _foo, 42
201      OutStreamer.EmitLocalCommonSymbol(GVSym, Size);
202      return;
203    }
204
205    // .local _foo
206    OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
207    // .comm _foo, 42, 4
208    OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
209    return;
210  }
211
212  const MCSection *TheSection =
213    getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
214
215  // Handle the zerofill directive on darwin, which is a special form of BSS
216  // emission.
217  if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
218    // .globl _foo
219    OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
220    // .zerofill __DATA, __common, _foo, 400, 5
221    OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
222    return;
223  }
224
225  OutStreamer.SwitchSection(TheSection);
226
227  // TODO: Factor into an 'emit linkage' thing that is shared with function
228  // bodies.
229  switch (GV->getLinkage()) {
230  case GlobalValue::CommonLinkage:
231  case GlobalValue::LinkOnceAnyLinkage:
232  case GlobalValue::LinkOnceODRLinkage:
233  case GlobalValue::WeakAnyLinkage:
234  case GlobalValue::WeakODRLinkage:
235  case GlobalValue::LinkerPrivateLinkage:
236    if (MAI->getWeakDefDirective() != 0) {
237      // .globl _foo
238      OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
239      // .weak_definition _foo
240      OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
241    } else if (const char *LinkOnce = MAI->getLinkOnceDirective()) {
242      // .globl _foo
243      OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
244      // .linkonce same_size
245      O << LinkOnce;
246    } else {
247      // .weak _foo
248      OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
249    }
250    break;
251  case GlobalValue::DLLExportLinkage:
252  case GlobalValue::AppendingLinkage:
253    // FIXME: appending linkage variables should go into a section of
254    // their name or something.  For now, just emit them as external.
255  case GlobalValue::ExternalLinkage:
256    // If external or appending, declare as a global symbol.
257    // .globl _foo
258    OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
259    break;
260  case GlobalValue::PrivateLinkage:
261  case GlobalValue::InternalLinkage:
262     break;
263  default:
264    llvm_unreachable("Unknown linkage type!");
265  }
266
267  EmitAlignment(AlignLog, GV);
268  if (VerboseAsm) {
269    WriteAsOperand(OutStreamer.GetCommentOS(), GV,
270                   /*PrintType=*/false, GV->getParent());
271    OutStreamer.GetCommentOS() << '\n';
272  }
273  OutStreamer.EmitLabel(GVSym);
274
275  EmitGlobalConstant(GV->getInitializer());
276
277  if (MAI->hasDotTypeDotSizeDirective())
278    OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
279
280  OutStreamer.AddBlankLine();
281}
282
283
284bool AsmPrinter::doFinalization(Module &M) {
285  // Emit global variables.
286  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
287       I != E; ++I)
288    EmitGlobalVariable(I);
289
290  // Emit final debug information.
291  if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
292    DW->EndModule();
293
294  // If the target wants to know about weak references, print them all.
295  if (MAI->getWeakRefDirective()) {
296    // FIXME: This is not lazy, it would be nice to only print weak references
297    // to stuff that is actually used.  Note that doing so would require targets
298    // to notice uses in operands (due to constant exprs etc).  This should
299    // happen with the MC stuff eventually.
300
301    // Print out module-level global variables here.
302    for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
303         I != E; ++I) {
304      if (!I->hasExternalWeakLinkage()) continue;
305      OutStreamer.EmitSymbolAttribute(GetGlobalValueSymbol(I),
306                                      MCSA_WeakReference);
307    }
308
309    for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
310      if (!I->hasExternalWeakLinkage()) continue;
311      OutStreamer.EmitSymbolAttribute(GetGlobalValueSymbol(I),
312                                      MCSA_WeakReference);
313    }
314  }
315
316  if (MAI->getSetDirective()) {
317    OutStreamer.AddBlankLine();
318    for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
319         I != E; ++I) {
320      MCSymbol *Name = GetGlobalValueSymbol(I);
321
322      const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
323      MCSymbol *Target = GetGlobalValueSymbol(GV);
324
325      if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
326        OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
327      else if (I->hasWeakLinkage())
328        OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
329      else
330        assert(I->hasLocalLinkage() && "Invalid alias linkage");
331
332      printVisibility(Name, I->getVisibility());
333
334      O << MAI->getSetDirective() << ' ' << *Name << ", " << *Target << '\n';
335    }
336  }
337
338  GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
339  assert(MI && "AsmPrinter didn't require GCModuleInfo?");
340  for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
341    if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
342      MP->finishAssembly(O, *this, *MAI);
343
344  // If we don't have any trampolines, then we don't require stack memory
345  // to be executable. Some targets have a directive to declare this.
346  Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
347  if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
348    if (MCSection *S = MAI->getNonexecutableStackSection(OutContext))
349      OutStreamer.SwitchSection(S);
350
351  // Allow the target to emit any magic that it wants at the end of the file,
352  // after everything else has gone out.
353  EmitEndOfAsmFile(M);
354
355  delete Mang; Mang = 0;
356  DW = 0; MMI = 0;
357
358  OutStreamer.Finish();
359  return false;
360}
361
362void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
363  // Get the function symbol.
364  CurrentFnSym = GetGlobalValueSymbol(MF.getFunction());
365  IncrementFunctionNumber();
366
367  if (VerboseAsm)
368    LI = &getAnalysis<MachineLoopInfo>();
369}
370
371namespace {
372  // SectionCPs - Keep track the alignment, constpool entries per Section.
373  struct SectionCPs {
374    const MCSection *S;
375    unsigned Alignment;
376    SmallVector<unsigned, 4> CPEs;
377    SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
378  };
379}
380
381/// EmitConstantPool - Print to the current output stream assembly
382/// representations of the constants in the constant pool MCP. This is
383/// used to print out constants which have been "spilled to memory" by
384/// the code generator.
385///
386void AsmPrinter::EmitConstantPool(MachineConstantPool *MCP) {
387  const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
388  if (CP.empty()) return;
389
390  // Calculate sections for constant pool entries. We collect entries to go into
391  // the same section together to reduce amount of section switch statements.
392  SmallVector<SectionCPs, 4> CPSections;
393  for (unsigned i = 0, e = CP.size(); i != e; ++i) {
394    const MachineConstantPoolEntry &CPE = CP[i];
395    unsigned Align = CPE.getAlignment();
396
397    SectionKind Kind;
398    switch (CPE.getRelocationInfo()) {
399    default: llvm_unreachable("Unknown section kind");
400    case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
401    case 1:
402      Kind = SectionKind::getReadOnlyWithRelLocal();
403      break;
404    case 0:
405    switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
406    case 4:  Kind = SectionKind::getMergeableConst4(); break;
407    case 8:  Kind = SectionKind::getMergeableConst8(); break;
408    case 16: Kind = SectionKind::getMergeableConst16();break;
409    default: Kind = SectionKind::getMergeableConst(); break;
410    }
411    }
412
413    const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
414
415    // The number of sections are small, just do a linear search from the
416    // last section to the first.
417    bool Found = false;
418    unsigned SecIdx = CPSections.size();
419    while (SecIdx != 0) {
420      if (CPSections[--SecIdx].S == S) {
421        Found = true;
422        break;
423      }
424    }
425    if (!Found) {
426      SecIdx = CPSections.size();
427      CPSections.push_back(SectionCPs(S, Align));
428    }
429
430    if (Align > CPSections[SecIdx].Alignment)
431      CPSections[SecIdx].Alignment = Align;
432    CPSections[SecIdx].CPEs.push_back(i);
433  }
434
435  // Now print stuff into the calculated sections.
436  for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
437    OutStreamer.SwitchSection(CPSections[i].S);
438    EmitAlignment(Log2_32(CPSections[i].Alignment));
439
440    unsigned Offset = 0;
441    for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
442      unsigned CPI = CPSections[i].CPEs[j];
443      MachineConstantPoolEntry CPE = CP[CPI];
444
445      // Emit inter-object padding for alignment.
446      unsigned AlignMask = CPE.getAlignment() - 1;
447      unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
448      OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/);
449
450      const Type *Ty = CPE.getType();
451      Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
452
453      // Emit the label with a comment on it.
454      if (VerboseAsm) {
455        OutStreamer.GetCommentOS() << "constant pool ";
456        WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(),
457                          MF->getFunction()->getParent());
458        OutStreamer.GetCommentOS() << '\n';
459      }
460      OutStreamer.EmitLabel(GetCPISymbol(CPI));
461
462      if (CPE.isMachineConstantPoolEntry())
463        EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
464      else
465        EmitGlobalConstant(CPE.Val.ConstVal);
466    }
467  }
468}
469
470/// EmitJumpTableInfo - Print assembly representations of the jump tables used
471/// by the current function to the current output stream.
472///
473void AsmPrinter::EmitJumpTableInfo(MachineJumpTableInfo *MJTI,
474                                   MachineFunction &MF) {
475  const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
476  if (JT.empty()) return;
477
478  bool IsPic = TM.getRelocationModel() == Reloc::PIC_;
479
480  // Pick the directive to use to print the jump table entries, and switch to
481  // the appropriate section.
482  TargetLowering *LoweringInfo = TM.getTargetLowering();
483
484  const Function *F = MF.getFunction();
485  bool JTInDiffSection = false;
486  if (F->isWeakForLinker() ||
487      (IsPic && !LoweringInfo->usesGlobalOffsetTable())) {
488    // In PIC mode, we need to emit the jump table to the same section as the
489    // function body itself, otherwise the label differences won't make sense.
490    // We should also do if the section name is NULL or function is declared in
491    // discardable section.
492    OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang,
493                                                                    TM));
494  } else {
495    // Otherwise, drop it in the readonly section.
496    const MCSection *ReadOnlySection =
497      getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
498    OutStreamer.SwitchSection(ReadOnlySection);
499    JTInDiffSection = true;
500  }
501
502  EmitAlignment(Log2_32(MJTI->getAlignment()));
503
504  for (unsigned i = 0, e = JT.size(); i != e; ++i) {
505    const std::vector<MachineBasicBlock*> &JTBBs = JT[i].MBBs;
506
507    // If this jump table was deleted, ignore it.
508    if (JTBBs.empty()) continue;
509
510    // For PIC codegen, if possible we want to use the SetDirective to reduce
511    // the number of relocations the assembler will generate for the jump table.
512    // Set directives are all printed before the jump table itself.
513    SmallPtrSet<MachineBasicBlock*, 16> EmittedSets;
514    if (MAI->getSetDirective() && IsPic)
515      for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
516        if (EmittedSets.insert(JTBBs[ii]))
517          printPICJumpTableSetLabel(i, JTBBs[ii]);
518
519    // On some targets (e.g. Darwin) we want to emit two consequtive labels
520    // before each jump table.  The first label is never referenced, but tells
521    // the assembler and linker the extents of the jump table object.  The
522    // second label is actually referenced by the code.
523    if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
524      OutStreamer.EmitLabel(GetJTISymbol(i, true));
525
526    OutStreamer.EmitLabel(GetJTISymbol(i));
527
528    for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
529      printPICJumpTableEntry(MJTI, JTBBs[ii], i);
530      O << '\n';
531    }
532  }
533}
534
535void AsmPrinter::printPICJumpTableEntry(const MachineJumpTableInfo *MJTI,
536                                        const MachineBasicBlock *MBB,
537                                        unsigned uid)  const {
538  bool isPIC = TM.getRelocationModel() == Reloc::PIC_;
539
540  // Use JumpTableDirective otherwise honor the entry size from the jump table
541  // info.
542  const char *JTEntryDirective = MAI->getJumpTableDirective(isPIC);
543  bool HadJTEntryDirective = JTEntryDirective != NULL;
544  if (!HadJTEntryDirective) {
545    JTEntryDirective = MJTI->getEntrySize() == 4 ?
546      MAI->getData32bitsDirective() : MAI->getData64bitsDirective();
547  }
548
549  O << JTEntryDirective << ' ';
550
551  // If we have emitted set directives for the jump table entries, print
552  // them rather than the entries themselves.  If we're emitting PIC, then
553  // emit the table entries as differences between two text section labels.
554  // If we're emitting non-PIC code, then emit the entries as direct
555  // references to the target basic blocks.
556  if (!isPIC) {
557    O << *GetMBBSymbol(MBB->getNumber());
558  } else if (MAI->getSetDirective()) {
559    O << MAI->getPrivateGlobalPrefix() << getFunctionNumber()
560      << '_' << uid << "_set_" << MBB->getNumber();
561  } else {
562    O << *GetMBBSymbol(MBB->getNumber());
563    // If the arch uses custom Jump Table directives, don't calc relative to
564    // JT.
565    if (!HadJTEntryDirective)
566      O << '-' << *GetJTISymbol(uid);
567  }
568}
569
570
571/// EmitSpecialLLVMGlobal - Check to see if the specified global is a
572/// special global used by LLVM.  If so, emit it and return true, otherwise
573/// do nothing and return false.
574bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
575  if (GV->getName() == "llvm.used") {
576    if (MAI->hasNoDeadStrip())    // No need to emit this at all.
577      EmitLLVMUsedList(GV->getInitializer());
578    return true;
579  }
580
581  // Ignore debug and non-emitted data.  This handles llvm.compiler.used.
582  if (GV->getSection() == "llvm.metadata" ||
583      GV->hasAvailableExternallyLinkage())
584    return true;
585
586  if (!GV->hasAppendingLinkage()) return false;
587
588  assert(GV->hasInitializer() && "Not a special LLVM global!");
589
590  const TargetData *TD = TM.getTargetData();
591  unsigned Align = Log2_32(TD->getPointerPrefAlignment());
592  if (GV->getName() == "llvm.global_ctors") {
593    OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection());
594    EmitAlignment(Align, 0);
595    EmitXXStructorList(GV->getInitializer());
596
597    if (TM.getRelocationModel() == Reloc::Static &&
598        MAI->hasStaticCtorDtorReferenceInStaticMode()) {
599      StringRef Sym(".constructors_used");
600      OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
601                                      MCSA_Reference);
602    }
603    return true;
604  }
605
606  if (GV->getName() == "llvm.global_dtors") {
607    OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection());
608    EmitAlignment(Align, 0);
609    EmitXXStructorList(GV->getInitializer());
610
611    if (TM.getRelocationModel() == Reloc::Static &&
612        MAI->hasStaticCtorDtorReferenceInStaticMode()) {
613      StringRef Sym(".destructors_used");
614      OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
615                                      MCSA_Reference);
616    }
617    return true;
618  }
619
620  return false;
621}
622
623/// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
624/// global in the specified llvm.used list for which emitUsedDirectiveFor
625/// is true, as being used with this directive.
626void AsmPrinter::EmitLLVMUsedList(Constant *List) {
627  // Should be an array of 'i8*'.
628  ConstantArray *InitList = dyn_cast<ConstantArray>(List);
629  if (InitList == 0) return;
630
631  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
632    const GlobalValue *GV =
633      dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
634    if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
635      OutStreamer.EmitSymbolAttribute(GetGlobalValueSymbol(GV),
636                                      MCSA_NoDeadStrip);
637  }
638}
639
640/// EmitXXStructorList - Emit the ctor or dtor list.  This just prints out the
641/// function pointers, ignoring the init priority.
642void AsmPrinter::EmitXXStructorList(Constant *List) {
643  // Should be an array of '{ int, void ()* }' structs.  The first value is the
644  // init priority, which we ignore.
645  if (!isa<ConstantArray>(List)) return;
646  ConstantArray *InitList = cast<ConstantArray>(List);
647  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
648    if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
649      if (CS->getNumOperands() != 2) return;  // Not array of 2-element structs.
650
651      if (CS->getOperand(1)->isNullValue())
652        return;  // Found a null terminator, exit printing.
653      // Emit the function pointer.
654      EmitGlobalConstant(CS->getOperand(1));
655    }
656}
657
658//===--------------------------------------------------------------------===//
659// Emission and print routines
660//
661
662/// EmitInt8 - Emit a byte directive and value.
663///
664void AsmPrinter::EmitInt8(int Value) const {
665  OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/);
666}
667
668/// EmitInt16 - Emit a short directive and value.
669///
670void AsmPrinter::EmitInt16(int Value) const {
671  OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/);
672}
673
674/// EmitInt32 - Emit a long directive and value.
675///
676void AsmPrinter::EmitInt32(int Value) const {
677  OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/);
678}
679
680/// EmitInt64 - Emit a long long directive and value.
681///
682void AsmPrinter::EmitInt64(uint64_t Value) const {
683  OutStreamer.EmitIntValue(Value, 8, 0/*addrspace*/);
684}
685
686
687/// toOctal - Convert the low order bits of X into an octal digit.
688///
689static inline char toOctal(int X) {
690  return (X&7)+'0';
691}
692
693/// printStringChar - Print a char, escaped if necessary.
694///
695static void printStringChar(formatted_raw_ostream &O, unsigned char C) {
696  if (C == '"') {
697    O << "\\\"";
698  } else if (C == '\\') {
699    O << "\\\\";
700  } else if (isprint((unsigned char)C)) {
701    O << C;
702  } else {
703    switch(C) {
704    case '\b': O << "\\b"; break;
705    case '\f': O << "\\f"; break;
706    case '\n': O << "\\n"; break;
707    case '\r': O << "\\r"; break;
708    case '\t': O << "\\t"; break;
709    default:
710      O << '\\';
711      O << toOctal(C >> 6);
712      O << toOctal(C >> 3);
713      O << toOctal(C >> 0);
714      break;
715    }
716  }
717}
718
719/// EmitFile - Emit a .file directive.
720void AsmPrinter::EmitFile(unsigned Number, StringRef Name) const {
721  O << "\t.file\t" << Number << " \"";
722  for (unsigned i = 0, N = Name.size(); i < N; ++i)
723    printStringChar(O, Name[i]);
724  O << '\"';
725}
726
727
728//===----------------------------------------------------------------------===//
729
730// EmitAlignment - Emit an alignment directive to the specified power of
731// two boundary.  For example, if you pass in 3 here, you will get an 8
732// byte alignment.  If a global value is specified, and if that global has
733// an explicit alignment requested, it will unconditionally override the
734// alignment request.  However, if ForcedAlignBits is specified, this value
735// has final say: the ultimate alignment will be the max of ForcedAlignBits
736// and the alignment computed with NumBits and the global.
737//
738// The algorithm is:
739//     Align = NumBits;
740//     if (GV && GV->hasalignment) Align = GV->getalignment();
741//     Align = std::max(Align, ForcedAlignBits);
742//
743void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
744                               unsigned ForcedAlignBits,
745                               bool UseFillExpr) const {
746  if (GV && GV->getAlignment())
747    NumBits = Log2_32(GV->getAlignment());
748  NumBits = std::max(NumBits, ForcedAlignBits);
749
750  if (NumBits == 0) return;   // No need to emit alignment.
751
752  unsigned FillValue = 0;
753  if (getCurrentSection()->getKind().isText())
754    FillValue = MAI->getTextAlignFillValue();
755
756  OutStreamer.EmitValueToAlignment(1 << NumBits, FillValue, 1, 0);
757}
758
759/// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
760///
761static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) {
762  MCContext &Ctx = AP.OutContext;
763
764  if (CV->isNullValue() || isa<UndefValue>(CV))
765    return MCConstantExpr::Create(0, Ctx);
766
767  if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
768    return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
769
770  if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
771    return MCSymbolRefExpr::Create(AP.GetGlobalValueSymbol(GV), Ctx);
772  if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
773    return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
774
775  const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
776  if (CE == 0) {
777    llvm_unreachable("Unknown constant value to lower!");
778    return MCConstantExpr::Create(0, Ctx);
779  }
780
781  switch (CE->getOpcode()) {
782  case Instruction::ZExt:
783  case Instruction::SExt:
784  case Instruction::FPTrunc:
785  case Instruction::FPExt:
786  case Instruction::UIToFP:
787  case Instruction::SIToFP:
788  case Instruction::FPToUI:
789  case Instruction::FPToSI:
790  default: llvm_unreachable("FIXME: Don't support this constant cast expr");
791  case Instruction::GetElementPtr: {
792    const TargetData &TD = *AP.TM.getTargetData();
793    // Generate a symbolic expression for the byte address
794    const Constant *PtrVal = CE->getOperand(0);
795    SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
796    int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0],
797                                         IdxVec.size());
798
799    const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
800    if (Offset == 0)
801      return Base;
802
803    // Truncate/sext the offset to the pointer size.
804    if (TD.getPointerSizeInBits() != 64) {
805      int SExtAmount = 64-TD.getPointerSizeInBits();
806      Offset = (Offset << SExtAmount) >> SExtAmount;
807    }
808
809    return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
810                                   Ctx);
811  }
812
813  case Instruction::Trunc:
814    // We emit the value and depend on the assembler to truncate the generated
815    // expression properly.  This is important for differences between
816    // blockaddress labels.  Since the two labels are in the same function, it
817    // is reasonable to treat their delta as a 32-bit value.
818    // FALL THROUGH.
819  case Instruction::BitCast:
820    return LowerConstant(CE->getOperand(0), AP);
821
822  case Instruction::IntToPtr: {
823    const TargetData &TD = *AP.TM.getTargetData();
824    // Handle casts to pointers by changing them into casts to the appropriate
825    // integer type.  This promotes constant folding and simplifies this code.
826    Constant *Op = CE->getOperand(0);
827    Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
828                                      false/*ZExt*/);
829    return LowerConstant(Op, AP);
830  }
831
832  case Instruction::PtrToInt: {
833    const TargetData &TD = *AP.TM.getTargetData();
834    // Support only foldable casts to/from pointers that can be eliminated by
835    // changing the pointer to the appropriately sized integer type.
836    Constant *Op = CE->getOperand(0);
837    const Type *Ty = CE->getType();
838
839    const MCExpr *OpExpr = LowerConstant(Op, AP);
840
841    // We can emit the pointer value into this slot if the slot is an
842    // integer slot equal to the size of the pointer.
843    if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
844      return OpExpr;
845
846    // Otherwise the pointer is smaller than the resultant integer, mask off
847    // the high bits so we are sure to get a proper truncation if the input is
848    // a constant expr.
849    unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
850    const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
851    return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
852  }
853
854  case Instruction::Add:
855  case Instruction::Sub:
856  case Instruction::And:
857  case Instruction::Or:
858  case Instruction::Xor: {
859    const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP);
860    const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP);
861    switch (CE->getOpcode()) {
862    default: llvm_unreachable("Unknown binary operator constant cast expr");
863    case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
864    case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
865    case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
866    case Instruction::Or:  return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
867    case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
868    }
869  }
870  }
871}
872
873static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
874                                    AsmPrinter &AP) {
875  if (AddrSpace != 0 || !CA->isString()) {
876    // Not a string.  Print the values in successive locations
877    for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
878      AP.EmitGlobalConstant(CA->getOperand(i), AddrSpace);
879    return;
880  }
881
882  // Otherwise, it can be emitted as .ascii.
883  SmallVector<char, 128> TmpVec;
884  TmpVec.reserve(CA->getNumOperands());
885  for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
886    TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
887
888  AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace);
889}
890
891static void EmitGlobalConstantVector(const ConstantVector *CV,
892                                     unsigned AddrSpace, AsmPrinter &AP) {
893  for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
894    AP.EmitGlobalConstant(CV->getOperand(i), AddrSpace);
895}
896
897static void EmitGlobalConstantStruct(const ConstantStruct *CS,
898                                     unsigned AddrSpace, AsmPrinter &AP) {
899  // Print the fields in successive locations. Pad to align if needed!
900  const TargetData *TD = AP.TM.getTargetData();
901  unsigned Size = TD->getTypeAllocSize(CS->getType());
902  const StructLayout *Layout = TD->getStructLayout(CS->getType());
903  uint64_t SizeSoFar = 0;
904  for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
905    const Constant *Field = CS->getOperand(i);
906
907    // Check if padding is needed and insert one or more 0s.
908    uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
909    uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
910                        - Layout->getElementOffset(i)) - FieldSize;
911    SizeSoFar += FieldSize + PadSize;
912
913    // Now print the actual field value.
914    AP.EmitGlobalConstant(Field, AddrSpace);
915
916    // Insert padding - this may include padding to increase the size of the
917    // current field up to the ABI size (if the struct is not packed) as well
918    // as padding to ensure that the next field starts at the right offset.
919    AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
920  }
921  assert(SizeSoFar == Layout->getSizeInBytes() &&
922         "Layout of constant struct may be incorrect!");
923}
924
925static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
926                                 AsmPrinter &AP) {
927  // FP Constants are printed as integer constants to avoid losing
928  // precision.
929  if (CFP->getType()->isDoubleTy()) {
930    if (AP.VerboseAsm) {
931      double Val = CFP->getValueAPF().convertToDouble();
932      AP.OutStreamer.GetCommentOS() << "double " << Val << '\n';
933    }
934
935    uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
936    AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
937    return;
938  }
939
940  if (CFP->getType()->isFloatTy()) {
941    if (AP.VerboseAsm) {
942      float Val = CFP->getValueAPF().convertToFloat();
943      AP.OutStreamer.GetCommentOS() << "float " << Val << '\n';
944    }
945    uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
946    AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace);
947    return;
948  }
949
950  if (CFP->getType()->isX86_FP80Ty()) {
951    // all long double variants are printed as hex
952    // api needed to prevent premature destruction
953    APInt API = CFP->getValueAPF().bitcastToAPInt();
954    const uint64_t *p = API.getRawData();
955    if (AP.VerboseAsm) {
956      // Convert to double so we can print the approximate val as a comment.
957      APFloat DoubleVal = CFP->getValueAPF();
958      bool ignored;
959      DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
960                        &ignored);
961      AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= "
962        << DoubleVal.convertToDouble() << '\n';
963    }
964
965    if (AP.TM.getTargetData()->isBigEndian()) {
966      AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
967      AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
968    } else {
969      AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
970      AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
971    }
972
973    // Emit the tail padding for the long double.
974    const TargetData &TD = *AP.TM.getTargetData();
975    AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
976                             TD.getTypeStoreSize(CFP->getType()), AddrSpace);
977    return;
978  }
979
980  assert(CFP->getType()->isPPC_FP128Ty() &&
981         "Floating point constant type not handled");
982  // All long double variants are printed as hex api needed to prevent
983  // premature destruction.
984  APInt API = CFP->getValueAPF().bitcastToAPInt();
985  const uint64_t *p = API.getRawData();
986  if (AP.TM.getTargetData()->isBigEndian()) {
987    AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
988    AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
989  } else {
990    AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
991    AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
992  }
993}
994
995static void EmitGlobalConstantLargeInt(const ConstantInt *CI,
996                                       unsigned AddrSpace, AsmPrinter &AP) {
997  const TargetData *TD = AP.TM.getTargetData();
998  unsigned BitWidth = CI->getBitWidth();
999  assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
1000
1001  // We don't expect assemblers to support integer data directives
1002  // for more than 64 bits, so we emit the data in at most 64-bit
1003  // quantities at a time.
1004  const uint64_t *RawData = CI->getValue().getRawData();
1005  for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1006    uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1007    AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1008  }
1009}
1010
1011/// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1012void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1013  if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) {
1014    uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1015    return OutStreamer.EmitZeros(Size, AddrSpace);
1016  }
1017
1018  if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1019    unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1020    switch (Size) {
1021    case 1:
1022    case 2:
1023    case 4:
1024    case 8:
1025      if (VerboseAsm)
1026        OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue());
1027      OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1028      return;
1029    default:
1030      EmitGlobalConstantLargeInt(CI, AddrSpace, *this);
1031      return;
1032    }
1033  }
1034
1035  if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1036    return EmitGlobalConstantArray(CVA, AddrSpace, *this);
1037
1038  if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1039    return EmitGlobalConstantStruct(CVS, AddrSpace, *this);
1040
1041  if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1042    return EmitGlobalConstantFP(CFP, AddrSpace, *this);
1043
1044  if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1045    return EmitGlobalConstantVector(V, AddrSpace, *this);
1046
1047  if (isa<ConstantPointerNull>(CV)) {
1048    unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1049    OutStreamer.EmitIntValue(0, Size, AddrSpace);
1050    return;
1051  }
1052
1053  // Otherwise, it must be a ConstantExpr.  Lower it to an MCExpr, then emit it
1054  // thread the streamer with EmitValue.
1055  OutStreamer.EmitValue(LowerConstant(CV, *this),
1056                        TM.getTargetData()->getTypeAllocSize(CV->getType()),
1057                        AddrSpace);
1058}
1059
1060void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1061  // Target doesn't support this yet!
1062  llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1063}
1064
1065/// PrintSpecial - Print information related to the specified machine instr
1066/// that is independent of the operand, and may be independent of the instr
1067/// itself.  This can be useful for portably encoding the comment character
1068/// or other bits of target-specific knowledge into the asmstrings.  The
1069/// syntax used is ${:comment}.  Targets can override this to add support
1070/// for their own strange codes.
1071void AsmPrinter::PrintSpecial(const MachineInstr *MI, const char *Code) const {
1072  if (!strcmp(Code, "private")) {
1073    O << MAI->getPrivateGlobalPrefix();
1074  } else if (!strcmp(Code, "comment")) {
1075    if (VerboseAsm)
1076      O << MAI->getCommentString();
1077  } else if (!strcmp(Code, "uid")) {
1078    // Comparing the address of MI isn't sufficient, because machineinstrs may
1079    // be allocated to the same address across functions.
1080    const Function *ThisF = MI->getParent()->getParent()->getFunction();
1081
1082    // If this is a new LastFn instruction, bump the counter.
1083    if (LastMI != MI || LastFn != ThisF) {
1084      ++Counter;
1085      LastMI = MI;
1086      LastFn = ThisF;
1087    }
1088    O << Counter;
1089  } else {
1090    std::string msg;
1091    raw_string_ostream Msg(msg);
1092    Msg << "Unknown special formatter '" << Code
1093         << "' for machine instr: " << *MI;
1094    llvm_report_error(Msg.str());
1095  }
1096}
1097
1098/// processDebugLoc - Processes the debug information of each machine
1099/// instruction's DebugLoc.
1100void AsmPrinter::processDebugLoc(const MachineInstr *MI,
1101                                 bool BeforePrintingInsn) {
1102  if (!MAI || !DW || !MAI->doesSupportDebugInformation()
1103      || !DW->ShouldEmitDwarfDebug())
1104    return;
1105  DebugLoc DL = MI->getDebugLoc();
1106  if (DL.isUnknown())
1107    return;
1108  DILocation CurDLT = MF->getDILocation(DL);
1109  if (CurDLT.getScope().isNull())
1110    return;
1111
1112  if (!BeforePrintingInsn) {
1113    // After printing instruction
1114    DW->EndScope(MI);
1115  } else if (CurDLT.getNode() != PrevDLT) {
1116    unsigned L = DW->RecordSourceLine(CurDLT.getLineNumber(),
1117                                      CurDLT.getColumnNumber(),
1118                                      CurDLT.getScope().getNode());
1119    printLabel(L);
1120    O << '\n';
1121    DW->BeginScope(MI, L);
1122    PrevDLT = CurDLT.getNode();
1123  }
1124}
1125
1126
1127/// printInlineAsm - This method formats and prints the specified machine
1128/// instruction that is an inline asm.
1129void AsmPrinter::printInlineAsm(const MachineInstr *MI) const {
1130  unsigned NumOperands = MI->getNumOperands();
1131
1132  // Count the number of register definitions.
1133  unsigned NumDefs = 0;
1134  for (; MI->getOperand(NumDefs).isReg() && MI->getOperand(NumDefs).isDef();
1135       ++NumDefs)
1136    assert(NumDefs != NumOperands-1 && "No asm string?");
1137
1138  assert(MI->getOperand(NumDefs).isSymbol() && "No asm string?");
1139
1140  // Disassemble the AsmStr, printing out the literal pieces, the operands, etc.
1141  const char *AsmStr = MI->getOperand(NumDefs).getSymbolName();
1142
1143  O << '\t';
1144
1145  // If this asmstr is empty, just print the #APP/#NOAPP markers.
1146  // These are useful to see where empty asm's wound up.
1147  if (AsmStr[0] == 0) {
1148    O << MAI->getCommentString() << MAI->getInlineAsmStart() << "\n\t";
1149    O << MAI->getCommentString() << MAI->getInlineAsmEnd() << '\n';
1150    return;
1151  }
1152
1153  O << MAI->getCommentString() << MAI->getInlineAsmStart() << "\n\t";
1154
1155  // The variant of the current asmprinter.
1156  int AsmPrinterVariant = MAI->getAssemblerDialect();
1157
1158  int CurVariant = -1;            // The number of the {.|.|.} region we are in.
1159  const char *LastEmitted = AsmStr; // One past the last character emitted.
1160
1161  while (*LastEmitted) {
1162    switch (*LastEmitted) {
1163    default: {
1164      // Not a special case, emit the string section literally.
1165      const char *LiteralEnd = LastEmitted+1;
1166      while (*LiteralEnd && *LiteralEnd != '{' && *LiteralEnd != '|' &&
1167             *LiteralEnd != '}' && *LiteralEnd != '$' && *LiteralEnd != '\n')
1168        ++LiteralEnd;
1169      if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1170        O.write(LastEmitted, LiteralEnd-LastEmitted);
1171      LastEmitted = LiteralEnd;
1172      break;
1173    }
1174    case '\n':
1175      ++LastEmitted;   // Consume newline character.
1176      O << '\n';       // Indent code with newline.
1177      break;
1178    case '$': {
1179      ++LastEmitted;   // Consume '$' character.
1180      bool Done = true;
1181
1182      // Handle escapes.
1183      switch (*LastEmitted) {
1184      default: Done = false; break;
1185      case '$':     // $$ -> $
1186        if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1187          O << '$';
1188        ++LastEmitted;  // Consume second '$' character.
1189        break;
1190      case '(':             // $( -> same as GCC's { character.
1191        ++LastEmitted;      // Consume '(' character.
1192        if (CurVariant != -1) {
1193          llvm_report_error("Nested variants found in inline asm string: '"
1194                            + std::string(AsmStr) + "'");
1195        }
1196        CurVariant = 0;     // We're in the first variant now.
1197        break;
1198      case '|':
1199        ++LastEmitted;  // consume '|' character.
1200        if (CurVariant == -1)
1201          O << '|';       // this is gcc's behavior for | outside a variant
1202        else
1203          ++CurVariant;   // We're in the next variant.
1204        break;
1205      case ')':         // $) -> same as GCC's } char.
1206        ++LastEmitted;  // consume ')' character.
1207        if (CurVariant == -1)
1208          O << '}';     // this is gcc's behavior for } outside a variant
1209        else
1210          CurVariant = -1;
1211        break;
1212      }
1213      if (Done) break;
1214
1215      bool HasCurlyBraces = false;
1216      if (*LastEmitted == '{') {     // ${variable}
1217        ++LastEmitted;               // Consume '{' character.
1218        HasCurlyBraces = true;
1219      }
1220
1221      // If we have ${:foo}, then this is not a real operand reference, it is a
1222      // "magic" string reference, just like in .td files.  Arrange to call
1223      // PrintSpecial.
1224      if (HasCurlyBraces && *LastEmitted == ':') {
1225        ++LastEmitted;
1226        const char *StrStart = LastEmitted;
1227        const char *StrEnd = strchr(StrStart, '}');
1228        if (StrEnd == 0) {
1229          llvm_report_error("Unterminated ${:foo} operand in inline asm string: '"
1230                            + std::string(AsmStr) + "'");
1231        }
1232
1233        std::string Val(StrStart, StrEnd);
1234        PrintSpecial(MI, Val.c_str());
1235        LastEmitted = StrEnd+1;
1236        break;
1237      }
1238
1239      const char *IDStart = LastEmitted;
1240      char *IDEnd;
1241      errno = 0;
1242      long Val = strtol(IDStart, &IDEnd, 10); // We only accept numbers for IDs.
1243      if (!isdigit(*IDStart) || (Val == 0 && errno == EINVAL)) {
1244        llvm_report_error("Bad $ operand number in inline asm string: '"
1245                          + std::string(AsmStr) + "'");
1246      }
1247      LastEmitted = IDEnd;
1248
1249      char Modifier[2] = { 0, 0 };
1250
1251      if (HasCurlyBraces) {
1252        // If we have curly braces, check for a modifier character.  This
1253        // supports syntax like ${0:u}, which correspond to "%u0" in GCC asm.
1254        if (*LastEmitted == ':') {
1255          ++LastEmitted;    // Consume ':' character.
1256          if (*LastEmitted == 0) {
1257            llvm_report_error("Bad ${:} expression in inline asm string: '"
1258                              + std::string(AsmStr) + "'");
1259          }
1260
1261          Modifier[0] = *LastEmitted;
1262          ++LastEmitted;    // Consume modifier character.
1263        }
1264
1265        if (*LastEmitted != '}') {
1266          llvm_report_error("Bad ${} expression in inline asm string: '"
1267                            + std::string(AsmStr) + "'");
1268        }
1269        ++LastEmitted;    // Consume '}' character.
1270      }
1271
1272      if ((unsigned)Val >= NumOperands-1) {
1273        llvm_report_error("Invalid $ operand number in inline asm string: '"
1274                          + std::string(AsmStr) + "'");
1275      }
1276
1277      // Okay, we finally have a value number.  Ask the target to print this
1278      // operand!
1279      if (CurVariant == -1 || CurVariant == AsmPrinterVariant) {
1280        unsigned OpNo = 1;
1281
1282        bool Error = false;
1283
1284        // Scan to find the machine operand number for the operand.
1285        for (; Val; --Val) {
1286          if (OpNo >= MI->getNumOperands()) break;
1287          unsigned OpFlags = MI->getOperand(OpNo).getImm();
1288          OpNo += InlineAsm::getNumOperandRegisters(OpFlags) + 1;
1289        }
1290
1291        if (OpNo >= MI->getNumOperands()) {
1292          Error = true;
1293        } else {
1294          unsigned OpFlags = MI->getOperand(OpNo).getImm();
1295          ++OpNo;  // Skip over the ID number.
1296
1297          if (Modifier[0] == 'l')  // labels are target independent
1298            O << *GetMBBSymbol(MI->getOperand(OpNo).getMBB()->getNumber());
1299          else {
1300            AsmPrinter *AP = const_cast<AsmPrinter*>(this);
1301            if ((OpFlags & 7) == 4) {
1302              Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant,
1303                                                Modifier[0] ? Modifier : 0);
1304            } else {
1305              Error = AP->PrintAsmOperand(MI, OpNo, AsmPrinterVariant,
1306                                          Modifier[0] ? Modifier : 0);
1307            }
1308          }
1309        }
1310        if (Error) {
1311          std::string msg;
1312          raw_string_ostream Msg(msg);
1313          Msg << "Invalid operand found in inline asm: '" << AsmStr << "'\n";
1314          MI->print(Msg);
1315          llvm_report_error(Msg.str());
1316        }
1317      }
1318      break;
1319    }
1320    }
1321  }
1322  O << "\n\t" << MAI->getCommentString() << MAI->getInlineAsmEnd();
1323}
1324
1325/// printImplicitDef - This method prints the specified machine instruction
1326/// that is an implicit def.
1327void AsmPrinter::printImplicitDef(const MachineInstr *MI) const {
1328  if (!VerboseAsm) return;
1329  O.PadToColumn(MAI->getCommentColumn());
1330  O << MAI->getCommentString() << " implicit-def: "
1331    << TRI->getName(MI->getOperand(0).getReg());
1332}
1333
1334void AsmPrinter::printKill(const MachineInstr *MI) const {
1335  if (!VerboseAsm) return;
1336  O.PadToColumn(MAI->getCommentColumn());
1337  O << MAI->getCommentString() << " kill:";
1338  for (unsigned n = 0, e = MI->getNumOperands(); n != e; ++n) {
1339    const MachineOperand &op = MI->getOperand(n);
1340    assert(op.isReg() && "KILL instruction must have only register operands");
1341    O << ' ' << TRI->getName(op.getReg()) << (op.isDef() ? "<def>" : "<kill>");
1342  }
1343}
1344
1345/// printLabel - This method prints a local label used by debug and
1346/// exception handling tables.
1347void AsmPrinter::printLabel(const MachineInstr *MI) const {
1348  printLabel(MI->getOperand(0).getImm());
1349}
1350
1351void AsmPrinter::printLabel(unsigned Id) const {
1352  O << MAI->getPrivateGlobalPrefix() << "label" << Id << ':';
1353}
1354
1355/// PrintAsmOperand - Print the specified operand of MI, an INLINEASM
1356/// instruction, using the specified assembler variant.  Targets should
1357/// override this to format as appropriate.
1358bool AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
1359                                 unsigned AsmVariant, const char *ExtraCode) {
1360  // Target doesn't support this yet!
1361  return true;
1362}
1363
1364bool AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
1365                                       unsigned AsmVariant,
1366                                       const char *ExtraCode) {
1367  // Target doesn't support this yet!
1368  return true;
1369}
1370
1371MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA,
1372                                            const char *Suffix) const {
1373  return GetBlockAddressSymbol(BA->getFunction(), BA->getBasicBlock(), Suffix);
1374}
1375
1376MCSymbol *AsmPrinter::GetBlockAddressSymbol(const Function *F,
1377                                            const BasicBlock *BB,
1378                                            const char *Suffix) const {
1379  assert(BB->hasName() &&
1380         "Address of anonymous basic block not supported yet!");
1381
1382  // This code must use the function name itself, and not the function number,
1383  // since it must be possible to generate the label name from within other
1384  // functions.
1385  SmallString<60> FnName;
1386  Mang->getNameWithPrefix(FnName, F, false);
1387
1388  // FIXME: THIS IS BROKEN IF THE LLVM BASIC BLOCK DOESN'T HAVE A NAME!
1389  SmallString<60> NameResult;
1390  Mang->getNameWithPrefix(NameResult,
1391                          StringRef("BA") + Twine((unsigned)FnName.size()) +
1392                          "_" + FnName.str() + "_" + BB->getName() + Suffix,
1393                          Mangler::Private);
1394
1395  return OutContext.GetOrCreateSymbol(NameResult.str());
1396}
1397
1398MCSymbol *AsmPrinter::GetMBBSymbol(unsigned MBBID) const {
1399  SmallString<60> Name;
1400  raw_svector_ostream(Name) << MAI->getPrivateGlobalPrefix() << "BB"
1401    << getFunctionNumber() << '_' << MBBID;
1402  return OutContext.GetOrCreateSymbol(Name.str());
1403}
1404
1405/// GetCPISymbol - Return the symbol for the specified constant pool entry.
1406MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1407  SmallString<60> Name;
1408  raw_svector_ostream(Name) << MAI->getPrivateGlobalPrefix() << "CPI"
1409    << getFunctionNumber() << '_' << CPID;
1410  return OutContext.GetOrCreateSymbol(Name.str());
1411}
1412
1413/// GetJTISymbol - Return the symbol for the specified jump table entry.
1414MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1415  const char *Prefix = isLinkerPrivate ? MAI->getLinkerPrivateGlobalPrefix() :
1416                                         MAI->getPrivateGlobalPrefix();
1417  SmallString<60> Name;
1418  raw_svector_ostream(Name) << Prefix << "JTI" << getFunctionNumber() << '_'
1419    << JTID;
1420  return OutContext.GetOrCreateSymbol(Name.str());
1421}
1422
1423/// GetGlobalValueSymbol - Return the MCSymbol for the specified global
1424/// value.
1425MCSymbol *AsmPrinter::GetGlobalValueSymbol(const GlobalValue *GV) const {
1426  SmallString<60> NameStr;
1427  Mang->getNameWithPrefix(NameStr, GV, false);
1428  return OutContext.GetOrCreateSymbol(NameStr.str());
1429}
1430
1431/// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1432/// global value name as its base, with the specified suffix, and where the
1433/// symbol is forced to have private linkage if ForcePrivate is true.
1434MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1435                                                   StringRef Suffix,
1436                                                   bool ForcePrivate) const {
1437  SmallString<60> NameStr;
1438  Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1439  NameStr.append(Suffix.begin(), Suffix.end());
1440  return OutContext.GetOrCreateSymbol(NameStr.str());
1441}
1442
1443/// GetExternalSymbolSymbol - Return the MCSymbol for the specified
1444/// ExternalSymbol.
1445MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
1446  SmallString<60> NameStr;
1447  Mang->getNameWithPrefix(NameStr, Sym);
1448  return OutContext.GetOrCreateSymbol(NameStr.str());
1449}
1450
1451
1452
1453/// PrintParentLoopComment - Print comments about parent loops of this one.
1454static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1455                                   unsigned FunctionNumber) {
1456  if (Loop == 0) return;
1457  PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
1458  OS.indent(Loop->getLoopDepth()*2)
1459    << "Parent Loop BB" << FunctionNumber << "_"
1460    << Loop->getHeader()->getNumber()
1461    << " Depth=" << Loop->getLoopDepth() << '\n';
1462}
1463
1464
1465/// PrintChildLoopComment - Print comments about child loops within
1466/// the loop for this basic block, with nesting.
1467static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1468                                  unsigned FunctionNumber) {
1469  // Add child loop information
1470  for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
1471    OS.indent((*CL)->getLoopDepth()*2)
1472      << "Child Loop BB" << FunctionNumber << "_"
1473      << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
1474      << '\n';
1475    PrintChildLoopComment(OS, *CL, FunctionNumber);
1476  }
1477}
1478
1479/// EmitComments - Pretty-print comments for basic blocks.
1480static void PrintBasicBlockLoopComments(const MachineBasicBlock &MBB,
1481                                        const MachineLoopInfo *LI,
1482                                        const AsmPrinter &AP) {
1483  // Add loop depth information
1484  const MachineLoop *Loop = LI->getLoopFor(&MBB);
1485  if (Loop == 0) return;
1486
1487  MachineBasicBlock *Header = Loop->getHeader();
1488  assert(Header && "No header for loop");
1489
1490  // If this block is not a loop header, just print out what is the loop header
1491  // and return.
1492  if (Header != &MBB) {
1493    AP.OutStreamer.AddComment("  in Loop: Header=BB" +
1494                              Twine(AP.getFunctionNumber())+"_" +
1495                              Twine(Loop->getHeader()->getNumber())+
1496                              " Depth="+Twine(Loop->getLoopDepth()));
1497    return;
1498  }
1499
1500  // Otherwise, it is a loop header.  Print out information about child and
1501  // parent loops.
1502  raw_ostream &OS = AP.OutStreamer.GetCommentOS();
1503
1504  PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
1505
1506  OS << "=>";
1507  OS.indent(Loop->getLoopDepth()*2-2);
1508
1509  OS << "This ";
1510  if (Loop->empty())
1511    OS << "Inner ";
1512  OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
1513
1514  PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
1515}
1516
1517
1518/// EmitBasicBlockStart - This method prints the label for the specified
1519/// MachineBasicBlock, an alignment (if present) and a comment describing
1520/// it if appropriate.
1521void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
1522  // Emit an alignment directive for this block, if needed.
1523  if (unsigned Align = MBB->getAlignment())
1524    EmitAlignment(Log2_32(Align));
1525
1526  // If the block has its address taken, emit a special label to satisfy
1527  // references to the block. This is done so that we don't need to
1528  // remember the number of this label, and so that we can make
1529  // forward references to labels without knowing what their numbers
1530  // will be.
1531  if (MBB->hasAddressTaken()) {
1532    const BasicBlock *BB = MBB->getBasicBlock();
1533    if (VerboseAsm)
1534      OutStreamer.AddComment("Address Taken");
1535    OutStreamer.EmitLabel(GetBlockAddressSymbol(BB->getParent(), BB));
1536  }
1537
1538  // Print the main label for the block.
1539  if (MBB->pred_empty() || MBB->isOnlyReachableByFallthrough()) {
1540    if (VerboseAsm) {
1541      // NOTE: Want this comment at start of line.
1542      O << MAI->getCommentString() << " BB#" << MBB->getNumber() << ':';
1543      if (const BasicBlock *BB = MBB->getBasicBlock())
1544        if (BB->hasName())
1545          OutStreamer.AddComment("%" + BB->getName());
1546
1547      PrintBasicBlockLoopComments(*MBB, LI, *this);
1548      OutStreamer.AddBlankLine();
1549    }
1550  } else {
1551    if (VerboseAsm) {
1552      if (const BasicBlock *BB = MBB->getBasicBlock())
1553        if (BB->hasName())
1554          OutStreamer.AddComment("%" + BB->getName());
1555      PrintBasicBlockLoopComments(*MBB, LI, *this);
1556    }
1557
1558    OutStreamer.EmitLabel(GetMBBSymbol(MBB->getNumber()));
1559  }
1560}
1561
1562/// printPICJumpTableSetLabel - This method prints a set label for the
1563/// specified MachineBasicBlock for a jumptable entry.
1564void AsmPrinter::printPICJumpTableSetLabel(unsigned uid,
1565                                           const MachineBasicBlock *MBB) const {
1566  if (!MAI->getSetDirective())
1567    return;
1568
1569  O << MAI->getSetDirective() << ' ' << MAI->getPrivateGlobalPrefix()
1570    << getFunctionNumber() << '_' << uid << "_set_" << MBB->getNumber() << ','
1571    << *GetMBBSymbol(MBB->getNumber())
1572    << '-' << *GetJTISymbol(uid) << '\n';
1573}
1574
1575void AsmPrinter::printPICJumpTableSetLabel(unsigned uid, unsigned uid2,
1576                                           const MachineBasicBlock *MBB) const {
1577  if (!MAI->getSetDirective())
1578    return;
1579
1580  O << MAI->getSetDirective() << ' ' << MAI->getPrivateGlobalPrefix()
1581    << getFunctionNumber() << '_' << uid << '_' << uid2
1582    << "_set_" << MBB->getNumber() << ','
1583    << *GetMBBSymbol(MBB->getNumber())
1584    << '-' << MAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
1585    << '_' << uid << '_' << uid2 << '\n';
1586}
1587
1588void AsmPrinter::printVisibility(MCSymbol *Sym, unsigned Visibility) const {
1589  MCSymbolAttr Attr = MCSA_Invalid;
1590
1591  switch (Visibility) {
1592  default: break;
1593  case GlobalValue::HiddenVisibility:
1594    Attr = MAI->getHiddenVisibilityAttr();
1595    break;
1596  case GlobalValue::ProtectedVisibility:
1597    Attr = MAI->getProtectedVisibilityAttr();
1598    break;
1599  }
1600
1601  if (Attr != MCSA_Invalid)
1602    OutStreamer.EmitSymbolAttribute(Sym, Attr);
1603}
1604
1605void AsmPrinter::printOffset(int64_t Offset) const {
1606  if (Offset > 0)
1607    O << '+' << Offset;
1608  else if (Offset < 0)
1609    O << Offset;
1610}
1611
1612GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1613  if (!S->usesMetadata())
1614    return 0;
1615
1616  gcp_iterator GCPI = GCMetadataPrinters.find(S);
1617  if (GCPI != GCMetadataPrinters.end())
1618    return GCPI->second;
1619
1620  const char *Name = S->getName().c_str();
1621
1622  for (GCMetadataPrinterRegistry::iterator
1623         I = GCMetadataPrinterRegistry::begin(),
1624         E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1625    if (strcmp(Name, I->getName()) == 0) {
1626      GCMetadataPrinter *GMP = I->instantiate();
1627      GMP->S = S;
1628      GCMetadataPrinters.insert(std::make_pair(S, GMP));
1629      return GMP;
1630    }
1631
1632  llvm_report_error("no GCMetadataPrinter registered for GC: " + Twine(Name));
1633  return 0;
1634}
1635
1636/// EmitComments - Pretty-print comments for instructions
1637void AsmPrinter::EmitComments(const MachineInstr &MI) const {
1638  if (!VerboseAsm)
1639    return;
1640
1641  bool Newline = false;
1642
1643  if (!MI.getDebugLoc().isUnknown()) {
1644    DILocation DLT = MF->getDILocation(MI.getDebugLoc());
1645
1646    // Print source line info.
1647    O.PadToColumn(MAI->getCommentColumn());
1648    O << MAI->getCommentString() << ' ';
1649    DIScope Scope = DLT.getScope();
1650    // Omit the directory, because it's likely to be long and uninteresting.
1651    if (!Scope.isNull())
1652      O << Scope.getFilename();
1653    else
1654      O << "<unknown>";
1655    O << ':' << DLT.getLineNumber();
1656    if (DLT.getColumnNumber() != 0)
1657      O << ':' << DLT.getColumnNumber();
1658    Newline = true;
1659  }
1660
1661  // Check for spills and reloads
1662  int FI;
1663
1664  const MachineFrameInfo *FrameInfo =
1665    MI.getParent()->getParent()->getFrameInfo();
1666
1667  // We assume a single instruction only has a spill or reload, not
1668  // both.
1669  const MachineMemOperand *MMO;
1670  if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
1671    if (FrameInfo->isSpillSlotObjectIndex(FI)) {
1672      MMO = *MI.memoperands_begin();
1673      if (Newline) O << '\n';
1674      O.PadToColumn(MAI->getCommentColumn());
1675      O << MAI->getCommentString() << ' ' << MMO->getSize() << "-byte Reload";
1676      Newline = true;
1677    }
1678  }
1679  else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
1680    if (FrameInfo->isSpillSlotObjectIndex(FI)) {
1681      if (Newline) O << '\n';
1682      O.PadToColumn(MAI->getCommentColumn());
1683      O << MAI->getCommentString() << ' '
1684        << MMO->getSize() << "-byte Folded Reload";
1685      Newline = true;
1686    }
1687  }
1688  else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
1689    if (FrameInfo->isSpillSlotObjectIndex(FI)) {
1690      MMO = *MI.memoperands_begin();
1691      if (Newline) O << '\n';
1692      O.PadToColumn(MAI->getCommentColumn());
1693      O << MAI->getCommentString() << ' ' << MMO->getSize() << "-byte Spill";
1694      Newline = true;
1695    }
1696  }
1697  else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
1698    if (FrameInfo->isSpillSlotObjectIndex(FI)) {
1699      if (Newline) O << '\n';
1700      O.PadToColumn(MAI->getCommentColumn());
1701      O << MAI->getCommentString() << ' '
1702        << MMO->getSize() << "-byte Folded Spill";
1703      Newline = true;
1704    }
1705  }
1706
1707  // Check for spill-induced copies
1708  unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
1709  if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg,
1710                                      SrcSubIdx, DstSubIdx)) {
1711    if (MI.getAsmPrinterFlag(ReloadReuse)) {
1712      if (Newline) O << '\n';
1713      O.PadToColumn(MAI->getCommentColumn());
1714      O << MAI->getCommentString() << " Reload Reuse";
1715    }
1716  }
1717}
1718
1719