AsmPrinter.cpp revision c82bd82aed933fa52a52b3b5d440fdf49fc85d88 
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/GCMetadataPrinter.h"
20#include "llvm/CodeGen/MachineConstantPool.h"
21#include "llvm/CodeGen/MachineJumpTableInfo.h"
22#include "llvm/CodeGen/MachineModuleInfo.h"
23#include "llvm/CodeGen/DwarfWriter.h"
24#include "llvm/Analysis/DebugInfo.h"
25#include "llvm/Support/CommandLine.h"
26#include "llvm/Support/Mangler.h"
27#include "llvm/Support/raw_ostream.h"
28#include "llvm/Target/TargetAsmInfo.h"
29#include "llvm/Target/TargetData.h"
30#include "llvm/Target/TargetLowering.h"
31#include "llvm/Target/TargetOptions.h"
32#include "llvm/Target/TargetRegisterInfo.h"
33#include "llvm/ADT/SmallPtrSet.h"
34#include "llvm/ADT/SmallString.h"
35#include "llvm/ADT/StringExtras.h"
36#include <cerrno>
37using namespace llvm;
38
39static cl::opt<cl::boolOrDefault>
40AsmVerbose("asm-verbose", cl::desc("Add comments to directives."),
41           cl::init(cl::BOU_UNSET));
42
43char AsmPrinter::ID = 0;
44AsmPrinter::AsmPrinter(raw_ostream &o, TargetMachine &tm,
45                       const TargetAsmInfo *T, CodeGenOpt::Level OL, bool VDef)
46  : MachineFunctionPass(&ID), FunctionNumber(0), OptLevel(OL), O(o),
47    TM(tm), TAI(T), TRI(tm.getRegisterInfo()),
48    IsInTextSection(false), LastMI(0), LastFn(0), Counter(~0U),
49    PrevDLT(0, ~0U, ~0U) {
50  DW = 0; MMI = 0;
51  switch (AsmVerbose) {
52  case cl::BOU_UNSET: VerboseAsm = VDef;  break;
53  case cl::BOU_TRUE:  VerboseAsm = true;  break;
54  case cl::BOU_FALSE: VerboseAsm = false; break;
55  }
56}
57
58AsmPrinter::~AsmPrinter() {
59  for (gcp_iterator I = GCMetadataPrinters.begin(),
60                    E = GCMetadataPrinters.end(); I != E; ++I)
61    delete I->second;
62}
63
64/// SwitchToTextSection - Switch to the specified text section of the executable
65/// if we are not already in it!
66///
67void AsmPrinter::SwitchToTextSection(const char *NewSection,
68                                     const GlobalValue *GV) {
69  std::string NS;
70  if (GV && GV->hasSection())
71    NS = TAI->getSwitchToSectionDirective() + GV->getSection();
72  else
73    NS = NewSection;
74
75  // If we're already in this section, we're done.
76  if (CurrentSection == NS) return;
77
78  // Close the current section, if applicable.
79  if (TAI->getSectionEndDirectiveSuffix() && !CurrentSection.empty())
80    O << CurrentSection << TAI->getSectionEndDirectiveSuffix() << '\n';
81
82  CurrentSection = NS;
83
84  if (!CurrentSection.empty())
85    O << CurrentSection << TAI->getTextSectionStartSuffix() << '\n';
86
87  IsInTextSection = true;
88}
89
90/// SwitchToDataSection - Switch to the specified data section of the executable
91/// if we are not already in it!
92///
93void AsmPrinter::SwitchToDataSection(const char *NewSection,
94                                     const GlobalValue *GV) {
95  std::string NS;
96  if (GV && GV->hasSection())
97    NS = TAI->getSwitchToSectionDirective() + GV->getSection();
98  else
99    NS = NewSection;
100
101  // If we're already in this section, we're done.
102  if (CurrentSection == NS) return;
103
104  // Close the current section, if applicable.
105  if (TAI->getSectionEndDirectiveSuffix() && !CurrentSection.empty())
106    O << CurrentSection << TAI->getSectionEndDirectiveSuffix() << '\n';
107
108  CurrentSection = NS;
109
110  if (!CurrentSection.empty())
111    O << CurrentSection << TAI->getDataSectionStartSuffix() << '\n';
112
113  IsInTextSection = false;
114}
115
116/// SwitchToSection - Switch to the specified section of the executable if we
117/// are not already in it!
118void AsmPrinter::SwitchToSection(const Section* NS) {
119  const std::string& NewSection = NS->getName();
120
121  // If we're already in this section, we're done.
122  if (CurrentSection == NewSection) return;
123
124  // Close the current section, if applicable.
125  if (TAI->getSectionEndDirectiveSuffix() && !CurrentSection.empty())
126    O << CurrentSection << TAI->getSectionEndDirectiveSuffix() << '\n';
127
128  // FIXME: Make CurrentSection a Section* in the future
129  CurrentSection = NewSection;
130  CurrentSection_ = NS;
131
132  if (!CurrentSection.empty()) {
133    // If section is named we need to switch into it via special '.section'
134    // directive and also append funky flags. Otherwise - section name is just
135    // some magic assembler directive.
136    if (NS->isNamed())
137      O << TAI->getSwitchToSectionDirective()
138        << CurrentSection
139        << TAI->getSectionFlags(NS->getFlags());
140    else
141      O << CurrentSection;
142    O << TAI->getDataSectionStartSuffix() << '\n';
143  }
144
145  IsInTextSection = (NS->getFlags() & SectionFlags::Code);
146}
147
148void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
149  MachineFunctionPass::getAnalysisUsage(AU);
150  AU.addRequired<GCModuleInfo>();
151}
152
153bool AsmPrinter::doInitialization(Module &M) {
154  Mang = new Mangler(M, TAI->getGlobalPrefix(), TAI->getPrivateGlobalPrefix());
155
156  if (TAI->doesAllowQuotesInName())
157    Mang->setUseQuotes(true);
158
159  GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
160  assert(MI && "AsmPrinter didn't require GCModuleInfo?");
161
162  if (TAI->hasSingleParameterDotFile()) {
163    /* Very minimal debug info. It is ignored if we emit actual
164       debug info. If we don't, this at helps the user find where
165       a function came from. */
166    O << "\t.file\t\"" << M.getModuleIdentifier() << "\"\n";
167  }
168
169  for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
170    if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
171      MP->beginAssembly(O, *this, *TAI);
172
173  if (!M.getModuleInlineAsm().empty())
174    O << TAI->getCommentString() << " Start of file scope inline assembly\n"
175      << M.getModuleInlineAsm()
176      << '\n' << TAI->getCommentString()
177      << " End of file scope inline assembly\n";
178
179  SwitchToDataSection("");   // Reset back to no section.
180
181  if (TAI->doesSupportDebugInformation() ||
182      TAI->doesSupportExceptionHandling()) {
183    MMI = getAnalysisIfAvailable<MachineModuleInfo>();
184    if (MMI)
185      MMI->AnalyzeModule(M);
186    DW = getAnalysisIfAvailable<DwarfWriter>();
187    if (DW)
188      DW->BeginModule(&M, MMI, O, this, TAI);
189  }
190
191  return false;
192}
193
194bool AsmPrinter::doFinalization(Module &M) {
195  // Emit final debug information.
196  if (TAI->doesSupportDebugInformation() || TAI->doesSupportExceptionHandling())
197    DW->EndModule();
198
199  // If the target wants to know about weak references, print them all.
200  if (TAI->getWeakRefDirective()) {
201    // FIXME: This is not lazy, it would be nice to only print weak references
202    // to stuff that is actually used.  Note that doing so would require targets
203    // to notice uses in operands (due to constant exprs etc).  This should
204    // happen with the MC stuff eventually.
205    SwitchToDataSection("");
206
207    // Print out module-level global variables here.
208    for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
209         I != E; ++I) {
210      if (I->hasExternalWeakLinkage())
211        O << TAI->getWeakRefDirective() << Mang->getValueName(I) << '\n';
212    }
213
214    for (Module::const_iterator I = M.begin(), E = M.end();
215         I != E; ++I) {
216      if (I->hasExternalWeakLinkage())
217        O << TAI->getWeakRefDirective() << Mang->getValueName(I) << '\n';
218    }
219  }
220
221  if (TAI->getSetDirective()) {
222    if (!M.alias_empty())
223      SwitchToSection(TAI->getTextSection());
224
225    O << '\n';
226    for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
227         I != E; ++I) {
228      std::string Name = Mang->getValueName(I);
229      std::string Target;
230
231      const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
232      Target = Mang->getValueName(GV);
233
234      if (I->hasExternalLinkage() || !TAI->getWeakRefDirective())
235        O << "\t.globl\t" << Name << '\n';
236      else if (I->hasWeakLinkage())
237        O << TAI->getWeakRefDirective() << Name << '\n';
238      else if (!I->hasLocalLinkage())
239        assert(0 && "Invalid alias linkage");
240
241      printVisibility(Name, I->getVisibility());
242
243      O << TAI->getSetDirective() << ' ' << Name << ", " << Target << '\n';
244    }
245  }
246
247  GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
248  assert(MI && "AsmPrinter didn't require GCModuleInfo?");
249  for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
250    if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
251      MP->finishAssembly(O, *this, *TAI);
252
253  // If we don't have any trampolines, then we don't require stack memory
254  // to be executable. Some targets have a directive to declare this.
255  Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
256  if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
257    if (TAI->getNonexecutableStackDirective())
258      O << TAI->getNonexecutableStackDirective() << '\n';
259
260  delete Mang; Mang = 0;
261  DW = 0; MMI = 0;
262  return false;
263}
264
265const std::string &
266AsmPrinter::getCurrentFunctionEHName(const MachineFunction *MF,
267                                     std::string &Name) const {
268  assert(MF && "No machine function?");
269  Name = MF->getFunction()->getName();
270  if (Name.empty())
271    Name = Mang->getValueName(MF->getFunction());
272  Name = Mang->makeNameProper(TAI->getEHGlobalPrefix() +
273                              Name + ".eh", TAI->getGlobalPrefix());
274  return Name;
275}
276
277void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
278  // What's my mangled name?
279  CurrentFnName = Mang->getValueName(MF.getFunction());
280  IncrementFunctionNumber();
281}
282
283namespace {
284  // SectionCPs - Keep track the alignment, constpool entries per Section.
285  struct SectionCPs {
286    const Section *S;
287    unsigned Alignment;
288    SmallVector<unsigned, 4> CPEs;
289    SectionCPs(const Section *s, unsigned a) : S(s), Alignment(a) {};
290  };
291}
292
293/// EmitConstantPool - Print to the current output stream assembly
294/// representations of the constants in the constant pool MCP. This is
295/// used to print out constants which have been "spilled to memory" by
296/// the code generator.
297///
298void AsmPrinter::EmitConstantPool(MachineConstantPool *MCP) {
299  const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
300  if (CP.empty()) return;
301
302  // Calculate sections for constant pool entries. We collect entries to go into
303  // the same section together to reduce amount of section switch statements.
304  SmallVector<SectionCPs, 4> CPSections;
305  for (unsigned i = 0, e = CP.size(); i != e; ++i) {
306    MachineConstantPoolEntry CPE = CP[i];
307    unsigned Align = CPE.getAlignment();
308    const Section* S = TAI->SelectSectionForMachineConst(CPE.getType());
309    // The number of sections are small, just do a linear search from the
310    // last section to the first.
311    bool Found = false;
312    unsigned SecIdx = CPSections.size();
313    while (SecIdx != 0) {
314      if (CPSections[--SecIdx].S == S) {
315        Found = true;
316        break;
317      }
318    }
319    if (!Found) {
320      SecIdx = CPSections.size();
321      CPSections.push_back(SectionCPs(S, Align));
322    }
323
324    if (Align > CPSections[SecIdx].Alignment)
325      CPSections[SecIdx].Alignment = Align;
326    CPSections[SecIdx].CPEs.push_back(i);
327  }
328
329  // Now print stuff into the calculated sections.
330  for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
331    SwitchToSection(CPSections[i].S);
332    EmitAlignment(Log2_32(CPSections[i].Alignment));
333
334    unsigned Offset = 0;
335    for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
336      unsigned CPI = CPSections[i].CPEs[j];
337      MachineConstantPoolEntry CPE = CP[CPI];
338
339      // Emit inter-object padding for alignment.
340      unsigned AlignMask = CPE.getAlignment() - 1;
341      unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
342      EmitZeros(NewOffset - Offset);
343
344      const Type *Ty = CPE.getType();
345      Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
346
347      O << TAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << '_'
348        << CPI << ":\t\t\t\t\t";
349      if (VerboseAsm) {
350        O << TAI->getCommentString() << ' ';
351        WriteTypeSymbolic(O, CPE.getType(), 0);
352      }
353      O << '\n';
354      if (CPE.isMachineConstantPoolEntry())
355        EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
356      else
357        EmitGlobalConstant(CPE.Val.ConstVal);
358    }
359  }
360}
361
362/// EmitJumpTableInfo - Print assembly representations of the jump tables used
363/// by the current function to the current output stream.
364///
365void AsmPrinter::EmitJumpTableInfo(MachineJumpTableInfo *MJTI,
366                                   MachineFunction &MF) {
367  const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
368  if (JT.empty()) return;
369
370  bool IsPic = TM.getRelocationModel() == Reloc::PIC_;
371
372  // Pick the directive to use to print the jump table entries, and switch to
373  // the appropriate section.
374  TargetLowering *LoweringInfo = TM.getTargetLowering();
375
376  const char* JumpTableDataSection = TAI->getJumpTableDataSection();
377  const Function *F = MF.getFunction();
378  unsigned SectionFlags = TAI->SectionFlagsForGlobal(F);
379  bool JTInDiffSection = false;
380  if ((IsPic && !(LoweringInfo && LoweringInfo->usesGlobalOffsetTable())) ||
381      !JumpTableDataSection ||
382      SectionFlags & SectionFlags::Linkonce) {
383    // In PIC mode, we need to emit the jump table to the same section as the
384    // function body itself, otherwise the label differences won't make sense.
385    // We should also do if the section name is NULL or function is declared in
386    // discardable section.
387    SwitchToSection(TAI->SectionForGlobal(F));
388  } else {
389    SwitchToDataSection(JumpTableDataSection);
390    JTInDiffSection = true;
391  }
392
393  EmitAlignment(Log2_32(MJTI->getAlignment()));
394
395  for (unsigned i = 0, e = JT.size(); i != e; ++i) {
396    const std::vector<MachineBasicBlock*> &JTBBs = JT[i].MBBs;
397
398    // If this jump table was deleted, ignore it.
399    if (JTBBs.empty()) continue;
400
401    // For PIC codegen, if possible we want to use the SetDirective to reduce
402    // the number of relocations the assembler will generate for the jump table.
403    // Set directives are all printed before the jump table itself.
404    SmallPtrSet<MachineBasicBlock*, 16> EmittedSets;
405    if (TAI->getSetDirective() && IsPic)
406      for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
407        if (EmittedSets.insert(JTBBs[ii]))
408          printPICJumpTableSetLabel(i, JTBBs[ii]);
409
410    // On some targets (e.g. darwin) we want to emit two consequtive labels
411    // before each jump table.  The first label is never referenced, but tells
412    // the assembler and linker the extents of the jump table object.  The
413    // second label is actually referenced by the code.
414    if (JTInDiffSection) {
415      if (const char *JTLabelPrefix = TAI->getJumpTableSpecialLabelPrefix())
416        O << JTLabelPrefix << "JTI" << getFunctionNumber() << '_' << i << ":\n";
417    }
418
419    O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
420      << '_' << i << ":\n";
421
422    for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
423      printPICJumpTableEntry(MJTI, JTBBs[ii], i);
424      O << '\n';
425    }
426  }
427}
428
429void AsmPrinter::printPICJumpTableEntry(const MachineJumpTableInfo *MJTI,
430                                        const MachineBasicBlock *MBB,
431                                        unsigned uid)  const {
432  bool IsPic = TM.getRelocationModel() == Reloc::PIC_;
433
434  // Use JumpTableDirective otherwise honor the entry size from the jump table
435  // info.
436  const char *JTEntryDirective = TAI->getJumpTableDirective();
437  bool HadJTEntryDirective = JTEntryDirective != NULL;
438  if (!HadJTEntryDirective) {
439    JTEntryDirective = MJTI->getEntrySize() == 4 ?
440      TAI->getData32bitsDirective() : TAI->getData64bitsDirective();
441  }
442
443  O << JTEntryDirective << ' ';
444
445  // If we have emitted set directives for the jump table entries, print
446  // them rather than the entries themselves.  If we're emitting PIC, then
447  // emit the table entries as differences between two text section labels.
448  // If we're emitting non-PIC code, then emit the entries as direct
449  // references to the target basic blocks.
450  if (IsPic) {
451    if (TAI->getSetDirective()) {
452      O << TAI->getPrivateGlobalPrefix() << getFunctionNumber()
453        << '_' << uid << "_set_" << MBB->getNumber();
454    } else {
455      printBasicBlockLabel(MBB, false, false, false);
456      // If the arch uses custom Jump Table directives, don't calc relative to
457      // JT
458      if (!HadJTEntryDirective)
459        O << '-' << TAI->getPrivateGlobalPrefix() << "JTI"
460          << getFunctionNumber() << '_' << uid;
461    }
462  } else {
463    printBasicBlockLabel(MBB, false, false, false);
464  }
465}
466
467
468/// EmitSpecialLLVMGlobal - Check to see if the specified global is a
469/// special global used by LLVM.  If so, emit it and return true, otherwise
470/// do nothing and return false.
471bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
472  if (GV->getName() == "llvm.used") {
473    if (TAI->getUsedDirective() != 0)    // No need to emit this at all.
474      EmitLLVMUsedList(GV->getInitializer());
475    return true;
476  }
477
478  // Ignore debug and non-emitted data.
479  if (GV->getSection() == "llvm.metadata" ||
480      GV->hasAvailableExternallyLinkage())
481    return true;
482
483  if (!GV->hasAppendingLinkage()) return false;
484
485  assert(GV->hasInitializer() && "Not a special LLVM global!");
486
487  const TargetData *TD = TM.getTargetData();
488  unsigned Align = Log2_32(TD->getPointerPrefAlignment());
489  if (GV->getName() == "llvm.global_ctors") {
490    SwitchToDataSection(TAI->getStaticCtorsSection());
491    EmitAlignment(Align, 0);
492    EmitXXStructorList(GV->getInitializer());
493    return true;
494  }
495
496  if (GV->getName() == "llvm.global_dtors") {
497    SwitchToDataSection(TAI->getStaticDtorsSection());
498    EmitAlignment(Align, 0);
499    EmitXXStructorList(GV->getInitializer());
500    return true;
501  }
502
503  return false;
504}
505
506/// findGlobalValue - if CV is an expression equivalent to a single
507/// global value, return that value.
508const GlobalValue * AsmPrinter::findGlobalValue(const Constant *CV) {
509  if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
510    return GV;
511  else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
512    const TargetData *TD = TM.getTargetData();
513    unsigned Opcode = CE->getOpcode();
514    switch (Opcode) {
515    case Instruction::GetElementPtr: {
516      const Constant *ptrVal = CE->getOperand(0);
517      SmallVector<Value*, 8> idxVec(CE->op_begin()+1, CE->op_end());
518      if (TD->getIndexedOffset(ptrVal->getType(), &idxVec[0], idxVec.size()))
519        return 0;
520      return findGlobalValue(ptrVal);
521    }
522    case Instruction::BitCast:
523      return findGlobalValue(CE->getOperand(0));
524    default:
525      return 0;
526    }
527  }
528  return 0;
529}
530
531/// EmitLLVMUsedList - For targets that define a TAI::UsedDirective, mark each
532/// global in the specified llvm.used list for which emitUsedDirectiveFor
533/// is true, as being used with this directive.
534
535void AsmPrinter::EmitLLVMUsedList(Constant *List) {
536  const char *Directive = TAI->getUsedDirective();
537
538  // Should be an array of 'i8*'.
539  ConstantArray *InitList = dyn_cast<ConstantArray>(List);
540  if (InitList == 0) return;
541
542  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
543    const GlobalValue *GV = findGlobalValue(InitList->getOperand(i));
544    if (TAI->emitUsedDirectiveFor(GV, Mang)) {
545      O << Directive;
546      EmitConstantValueOnly(InitList->getOperand(i));
547      O << '\n';
548    }
549  }
550}
551
552/// EmitXXStructorList - Emit the ctor or dtor list.  This just prints out the
553/// function pointers, ignoring the init priority.
554void AsmPrinter::EmitXXStructorList(Constant *List) {
555  // Should be an array of '{ int, void ()* }' structs.  The first value is the
556  // init priority, which we ignore.
557  if (!isa<ConstantArray>(List)) return;
558  ConstantArray *InitList = cast<ConstantArray>(List);
559  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
560    if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
561      if (CS->getNumOperands() != 2) return;  // Not array of 2-element structs.
562
563      if (CS->getOperand(1)->isNullValue())
564        return;  // Found a null terminator, exit printing.
565      // Emit the function pointer.
566      EmitGlobalConstant(CS->getOperand(1));
567    }
568}
569
570/// getGlobalLinkName - Returns the asm/link name of of the specified
571/// global variable.  Should be overridden by each target asm printer to
572/// generate the appropriate value.
573const std::string &AsmPrinter::getGlobalLinkName(const GlobalVariable *GV,
574                                                 std::string &LinkName) const {
575  if (isa<Function>(GV)) {
576    LinkName += TAI->getFunctionAddrPrefix();
577    LinkName += Mang->getValueName(GV);
578    LinkName += TAI->getFunctionAddrSuffix();
579  } else {
580    LinkName += TAI->getGlobalVarAddrPrefix();
581    LinkName += Mang->getValueName(GV);
582    LinkName += TAI->getGlobalVarAddrSuffix();
583  }
584
585  return LinkName;
586}
587
588/// EmitExternalGlobal - Emit the external reference to a global variable.
589/// Should be overridden if an indirect reference should be used.
590void AsmPrinter::EmitExternalGlobal(const GlobalVariable *GV) {
591  std::string GLN;
592  O << getGlobalLinkName(GV, GLN);
593}
594
595
596
597//===----------------------------------------------------------------------===//
598/// LEB 128 number encoding.
599
600/// PrintULEB128 - Print a series of hexidecimal values (separated by commas)
601/// representing an unsigned leb128 value.
602void AsmPrinter::PrintULEB128(unsigned Value) const {
603  char Buffer[20];
604  do {
605    unsigned char Byte = static_cast<unsigned char>(Value & 0x7f);
606    Value >>= 7;
607    if (Value) Byte |= 0x80;
608    O << "0x" << utohex_buffer(Byte, Buffer+20);
609    if (Value) O << ", ";
610  } while (Value);
611}
612
613/// PrintSLEB128 - Print a series of hexidecimal values (separated by commas)
614/// representing a signed leb128 value.
615void AsmPrinter::PrintSLEB128(int Value) const {
616  int Sign = Value >> (8 * sizeof(Value) - 1);
617  bool IsMore;
618  char Buffer[20];
619
620  do {
621    unsigned char Byte = static_cast<unsigned char>(Value & 0x7f);
622    Value >>= 7;
623    IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0;
624    if (IsMore) Byte |= 0x80;
625    O << "0x" << utohex_buffer(Byte, Buffer+20);
626    if (IsMore) O << ", ";
627  } while (IsMore);
628}
629
630//===--------------------------------------------------------------------===//
631// Emission and print routines
632//
633
634/// PrintHex - Print a value as a hexidecimal value.
635///
636void AsmPrinter::PrintHex(int Value) const {
637  char Buffer[20];
638  O << "0x" << utohex_buffer(static_cast<unsigned>(Value), Buffer+20);
639}
640
641/// EOL - Print a newline character to asm stream.  If a comment is present
642/// then it will be printed first.  Comments should not contain '\n'.
643void AsmPrinter::EOL() const {
644  O << '\n';
645}
646
647void AsmPrinter::EOL(const std::string &Comment) const {
648  if (VerboseAsm && !Comment.empty()) {
649    O << '\t'
650      << TAI->getCommentString()
651      << ' '
652      << Comment;
653  }
654  O << '\n';
655}
656
657void AsmPrinter::EOL(const char* Comment) const {
658  if (VerboseAsm && *Comment) {
659    O << '\t'
660      << TAI->getCommentString()
661      << ' '
662      << Comment;
663  }
664  O << '\n';
665}
666
667/// EmitULEB128Bytes - Emit an assembler byte data directive to compose an
668/// unsigned leb128 value.
669void AsmPrinter::EmitULEB128Bytes(unsigned Value) const {
670  if (TAI->hasLEB128()) {
671    O << "\t.uleb128\t"
672      << Value;
673  } else {
674    O << TAI->getData8bitsDirective();
675    PrintULEB128(Value);
676  }
677}
678
679/// EmitSLEB128Bytes - print an assembler byte data directive to compose a
680/// signed leb128 value.
681void AsmPrinter::EmitSLEB128Bytes(int Value) const {
682  if (TAI->hasLEB128()) {
683    O << "\t.sleb128\t"
684      << Value;
685  } else {
686    O << TAI->getData8bitsDirective();
687    PrintSLEB128(Value);
688  }
689}
690
691/// EmitInt8 - Emit a byte directive and value.
692///
693void AsmPrinter::EmitInt8(int Value) const {
694  O << TAI->getData8bitsDirective();
695  PrintHex(Value & 0xFF);
696}
697
698/// EmitInt16 - Emit a short directive and value.
699///
700void AsmPrinter::EmitInt16(int Value) const {
701  O << TAI->getData16bitsDirective();
702  PrintHex(Value & 0xFFFF);
703}
704
705/// EmitInt32 - Emit a long directive and value.
706///
707void AsmPrinter::EmitInt32(int Value) const {
708  O << TAI->getData32bitsDirective();
709  PrintHex(Value);
710}
711
712/// EmitInt64 - Emit a long long directive and value.
713///
714void AsmPrinter::EmitInt64(uint64_t Value) const {
715  if (TAI->getData64bitsDirective()) {
716    O << TAI->getData64bitsDirective();
717    PrintHex(Value);
718  } else {
719    if (TM.getTargetData()->isBigEndian()) {
720      EmitInt32(unsigned(Value >> 32)); O << '\n';
721      EmitInt32(unsigned(Value));
722    } else {
723      EmitInt32(unsigned(Value)); O << '\n';
724      EmitInt32(unsigned(Value >> 32));
725    }
726  }
727}
728
729/// toOctal - Convert the low order bits of X into an octal digit.
730///
731static inline char toOctal(int X) {
732  return (X&7)+'0';
733}
734
735/// printStringChar - Print a char, escaped if necessary.
736///
737static void printStringChar(raw_ostream &O, unsigned char C) {
738  if (C == '"') {
739    O << "\\\"";
740  } else if (C == '\\') {
741    O << "\\\\";
742  } else if (isprint((unsigned char)C)) {
743    O << C;
744  } else {
745    switch(C) {
746    case '\b': O << "\\b"; break;
747    case '\f': O << "\\f"; break;
748    case '\n': O << "\\n"; break;
749    case '\r': O << "\\r"; break;
750    case '\t': O << "\\t"; break;
751    default:
752      O << '\\';
753      O << toOctal(C >> 6);
754      O << toOctal(C >> 3);
755      O << toOctal(C >> 0);
756      break;
757    }
758  }
759}
760
761/// EmitString - Emit a string with quotes and a null terminator.
762/// Special characters are emitted properly.
763/// \literal (Eg. '\t') \endliteral
764void AsmPrinter::EmitString(const std::string &String) const {
765  EmitString(String.c_str(), String.size());
766}
767
768void AsmPrinter::EmitString(const char *String, unsigned Size) const {
769  const char* AscizDirective = TAI->getAscizDirective();
770  if (AscizDirective)
771    O << AscizDirective;
772  else
773    O << TAI->getAsciiDirective();
774  O << '\"';
775  for (unsigned i = 0; i < Size; ++i)
776    printStringChar(O, String[i]);
777  if (AscizDirective)
778    O << '\"';
779  else
780    O << "\\0\"";
781}
782
783
784/// EmitFile - Emit a .file directive.
785void AsmPrinter::EmitFile(unsigned Number, const std::string &Name) const {
786  O << "\t.file\t" << Number << " \"";
787  for (unsigned i = 0, N = Name.size(); i < N; ++i)
788    printStringChar(O, Name[i]);
789  O << '\"';
790}
791
792
793//===----------------------------------------------------------------------===//
794
795// EmitAlignment - Emit an alignment directive to the specified power of
796// two boundary.  For example, if you pass in 3 here, you will get an 8
797// byte alignment.  If a global value is specified, and if that global has
798// an explicit alignment requested, it will unconditionally override the
799// alignment request.  However, if ForcedAlignBits is specified, this value
800// has final say: the ultimate alignment will be the max of ForcedAlignBits
801// and the alignment computed with NumBits and the global.
802//
803// The algorithm is:
804//     Align = NumBits;
805//     if (GV && GV->hasalignment) Align = GV->getalignment();
806//     Align = std::max(Align, ForcedAlignBits);
807//
808void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
809                               unsigned ForcedAlignBits,
810                               bool UseFillExpr) const {
811  if (GV && GV->getAlignment())
812    NumBits = Log2_32(GV->getAlignment());
813  NumBits = std::max(NumBits, ForcedAlignBits);
814
815  if (NumBits == 0) return;   // No need to emit alignment.
816  if (TAI->getAlignmentIsInBytes()) NumBits = 1 << NumBits;
817  O << TAI->getAlignDirective() << NumBits;
818
819  unsigned FillValue = TAI->getTextAlignFillValue();
820  UseFillExpr &= IsInTextSection && FillValue;
821  if (UseFillExpr) {
822    O << ',';
823    PrintHex(FillValue);
824  }
825  O << '\n';
826}
827
828
829/// EmitZeros - Emit a block of zeros.
830///
831void AsmPrinter::EmitZeros(uint64_t NumZeros, unsigned AddrSpace) const {
832  if (NumZeros) {
833    if (TAI->getZeroDirective()) {
834      O << TAI->getZeroDirective() << NumZeros;
835      if (TAI->getZeroDirectiveSuffix())
836        O << TAI->getZeroDirectiveSuffix();
837      O << '\n';
838    } else {
839      for (; NumZeros; --NumZeros)
840        O << TAI->getData8bitsDirective(AddrSpace) << "0\n";
841    }
842  }
843}
844
845// Print out the specified constant, without a storage class.  Only the
846// constants valid in constant expressions can occur here.
847void AsmPrinter::EmitConstantValueOnly(const Constant *CV) {
848  if (CV->isNullValue() || isa<UndefValue>(CV))
849    O << '0';
850  else if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
851    O << CI->getZExtValue();
852  } else if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV)) {
853    // This is a constant address for a global variable or function. Use the
854    // name of the variable or function as the address value, possibly
855    // decorating it with GlobalVarAddrPrefix/Suffix or
856    // FunctionAddrPrefix/Suffix (these all default to "" )
857    if (isa<Function>(GV)) {
858      O << TAI->getFunctionAddrPrefix()
859        << Mang->getValueName(GV)
860        << TAI->getFunctionAddrSuffix();
861    } else {
862      O << TAI->getGlobalVarAddrPrefix()
863        << Mang->getValueName(GV)
864        << TAI->getGlobalVarAddrSuffix();
865    }
866  } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
867    const TargetData *TD = TM.getTargetData();
868    unsigned Opcode = CE->getOpcode();
869    switch (Opcode) {
870    case Instruction::GetElementPtr: {
871      // generate a symbolic expression for the byte address
872      const Constant *ptrVal = CE->getOperand(0);
873      SmallVector<Value*, 8> idxVec(CE->op_begin()+1, CE->op_end());
874      if (int64_t Offset = TD->getIndexedOffset(ptrVal->getType(), &idxVec[0],
875                                                idxVec.size())) {
876        // Truncate/sext the offset to the pointer size.
877        if (TD->getPointerSizeInBits() != 64) {
878          int SExtAmount = 64-TD->getPointerSizeInBits();
879          Offset = (Offset << SExtAmount) >> SExtAmount;
880        }
881
882        if (Offset)
883          O << '(';
884        EmitConstantValueOnly(ptrVal);
885        if (Offset > 0)
886          O << ") + " << Offset;
887        else if (Offset < 0)
888          O << ") - " << -Offset;
889      } else {
890        EmitConstantValueOnly(ptrVal);
891      }
892      break;
893    }
894    case Instruction::Trunc:
895    case Instruction::ZExt:
896    case Instruction::SExt:
897    case Instruction::FPTrunc:
898    case Instruction::FPExt:
899    case Instruction::UIToFP:
900    case Instruction::SIToFP:
901    case Instruction::FPToUI:
902    case Instruction::FPToSI:
903      assert(0 && "FIXME: Don't yet support this kind of constant cast expr");
904      break;
905    case Instruction::BitCast:
906      return EmitConstantValueOnly(CE->getOperand(0));
907
908    case Instruction::IntToPtr: {
909      // Handle casts to pointers by changing them into casts to the appropriate
910      // integer type.  This promotes constant folding and simplifies this code.
911      Constant *Op = CE->getOperand(0);
912      Op = ConstantExpr::getIntegerCast(Op, TD->getIntPtrType(), false/*ZExt*/);
913      return EmitConstantValueOnly(Op);
914    }
915
916
917    case Instruction::PtrToInt: {
918      // Support only foldable casts to/from pointers that can be eliminated by
919      // changing the pointer to the appropriately sized integer type.
920      Constant *Op = CE->getOperand(0);
921      const Type *Ty = CE->getType();
922
923      // We can emit the pointer value into this slot if the slot is an
924      // integer slot greater or equal to the size of the pointer.
925      if (TD->getTypeAllocSize(Ty) >= TD->getTypeAllocSize(Op->getType()))
926        return EmitConstantValueOnly(Op);
927
928      O << "((";
929      EmitConstantValueOnly(Op);
930      APInt ptrMask = APInt::getAllOnesValue(TD->getTypeAllocSizeInBits(Ty));
931
932      SmallString<40> S;
933      ptrMask.toStringUnsigned(S);
934      O << ") & " << S.c_str() << ')';
935      break;
936    }
937    case Instruction::Add:
938    case Instruction::Sub:
939    case Instruction::And:
940    case Instruction::Or:
941    case Instruction::Xor:
942      O << '(';
943      EmitConstantValueOnly(CE->getOperand(0));
944      O << ')';
945      switch (Opcode) {
946      case Instruction::Add:
947       O << " + ";
948       break;
949      case Instruction::Sub:
950       O << " - ";
951       break;
952      case Instruction::And:
953       O << " & ";
954       break;
955      case Instruction::Or:
956       O << " | ";
957       break;
958      case Instruction::Xor:
959       O << " ^ ";
960       break;
961      default:
962       break;
963      }
964      O << '(';
965      EmitConstantValueOnly(CE->getOperand(1));
966      O << ')';
967      break;
968    default:
969      assert(0 && "Unsupported operator!");
970    }
971  } else {
972    assert(0 && "Unknown constant value!");
973  }
974}
975
976/// printAsCString - Print the specified array as a C compatible string, only if
977/// the predicate isString is true.
978///
979static void printAsCString(raw_ostream &O, const ConstantArray *CVA,
980                           unsigned LastElt) {
981  assert(CVA->isString() && "Array is not string compatible!");
982
983  O << '\"';
984  for (unsigned i = 0; i != LastElt; ++i) {
985    unsigned char C =
986        (unsigned char)cast<ConstantInt>(CVA->getOperand(i))->getZExtValue();
987    printStringChar(O, C);
988  }
989  O << '\"';
990}
991
992/// EmitString - Emit a zero-byte-terminated string constant.
993///
994void AsmPrinter::EmitString(const ConstantArray *CVA) const {
995  unsigned NumElts = CVA->getNumOperands();
996  if (TAI->getAscizDirective() && NumElts &&
997      cast<ConstantInt>(CVA->getOperand(NumElts-1))->getZExtValue() == 0) {
998    O << TAI->getAscizDirective();
999    printAsCString(O, CVA, NumElts-1);
1000  } else {
1001    O << TAI->getAsciiDirective();
1002    printAsCString(O, CVA, NumElts);
1003  }
1004  O << '\n';
1005}
1006
1007void AsmPrinter::EmitGlobalConstantArray(const ConstantArray *CVA,
1008                                         unsigned AddrSpace) {
1009  if (CVA->isString()) {
1010    EmitString(CVA);
1011  } else { // Not a string.  Print the values in successive locations
1012    for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i)
1013      EmitGlobalConstant(CVA->getOperand(i), AddrSpace);
1014  }
1015}
1016
1017void AsmPrinter::EmitGlobalConstantVector(const ConstantVector *CP) {
1018  const VectorType *PTy = CP->getType();
1019
1020  for (unsigned I = 0, E = PTy->getNumElements(); I < E; ++I)
1021    EmitGlobalConstant(CP->getOperand(I));
1022}
1023
1024void AsmPrinter::EmitGlobalConstantStruct(const ConstantStruct *CVS,
1025                                          unsigned AddrSpace) {
1026  // Print the fields in successive locations. Pad to align if needed!
1027  const TargetData *TD = TM.getTargetData();
1028  unsigned Size = TD->getTypeAllocSize(CVS->getType());
1029  const StructLayout *cvsLayout = TD->getStructLayout(CVS->getType());
1030  uint64_t sizeSoFar = 0;
1031  for (unsigned i = 0, e = CVS->getNumOperands(); i != e; ++i) {
1032    const Constant* field = CVS->getOperand(i);
1033
1034    // Check if padding is needed and insert one or more 0s.
1035    uint64_t fieldSize = TD->getTypeAllocSize(field->getType());
1036    uint64_t padSize = ((i == e-1 ? Size : cvsLayout->getElementOffset(i+1))
1037                        - cvsLayout->getElementOffset(i)) - fieldSize;
1038    sizeSoFar += fieldSize + padSize;
1039
1040    // Now print the actual field value.
1041    EmitGlobalConstant(field, AddrSpace);
1042
1043    // Insert padding - this may include padding to increase the size of the
1044    // current field up to the ABI size (if the struct is not packed) as well
1045    // as padding to ensure that the next field starts at the right offset.
1046    EmitZeros(padSize, AddrSpace);
1047  }
1048  assert(sizeSoFar == cvsLayout->getSizeInBytes() &&
1049         "Layout of constant struct may be incorrect!");
1050}
1051
1052void AsmPrinter::EmitGlobalConstantFP(const ConstantFP *CFP,
1053                                      unsigned AddrSpace) {
1054  // FP Constants are printed as integer constants to avoid losing
1055  // precision...
1056  const TargetData *TD = TM.getTargetData();
1057  if (CFP->getType() == Type::DoubleTy) {
1058    double Val = CFP->getValueAPF().convertToDouble();  // for comment only
1059    uint64_t i = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1060    if (TAI->getData64bitsDirective(AddrSpace)) {
1061      O << TAI->getData64bitsDirective(AddrSpace) << i;
1062      if (VerboseAsm)
1063        O << '\t' << TAI->getCommentString() << " double value: " << Val;
1064      O << '\n';
1065    } else if (TD->isBigEndian()) {
1066      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i >> 32);
1067      if (VerboseAsm)
1068        O << '\t' << TAI->getCommentString()
1069          << " double most significant word " << Val;
1070      O << '\n';
1071      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i);
1072      if (VerboseAsm)
1073        O << '\t' << TAI->getCommentString()
1074          << " double least significant word " << Val;
1075      O << '\n';
1076    } else {
1077      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i);
1078      if (VerboseAsm)
1079        O << '\t' << TAI->getCommentString()
1080          << " double least significant word " << Val;
1081      O << '\n';
1082      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i >> 32);
1083      if (VerboseAsm)
1084        O << '\t' << TAI->getCommentString()
1085          << " double most significant word " << Val;
1086      O << '\n';
1087    }
1088    return;
1089  } else if (CFP->getType() == Type::FloatTy) {
1090    float Val = CFP->getValueAPF().convertToFloat();  // for comment only
1091    O << TAI->getData32bitsDirective(AddrSpace)
1092      << CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1093    if (VerboseAsm)
1094      O << '\t' << TAI->getCommentString() << " float " << Val;
1095    O << '\n';
1096    return;
1097  } else if (CFP->getType() == Type::X86_FP80Ty) {
1098    // all long double variants are printed as hex
1099    // api needed to prevent premature destruction
1100    APInt api = CFP->getValueAPF().bitcastToAPInt();
1101    const uint64_t *p = api.getRawData();
1102    // Convert to double so we can print the approximate val as a comment.
1103    APFloat DoubleVal = CFP->getValueAPF();
1104    bool ignored;
1105    DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1106                      &ignored);
1107    if (TD->isBigEndian()) {
1108      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[1]);
1109      if (VerboseAsm)
1110        O << '\t' << TAI->getCommentString()
1111          << " long double most significant halfword of ~"
1112          << DoubleVal.convertToDouble();
1113      O << '\n';
1114      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 48);
1115      if (VerboseAsm)
1116        O << '\t' << TAI->getCommentString() << " long double next halfword";
1117      O << '\n';
1118      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 32);
1119      if (VerboseAsm)
1120        O << '\t' << TAI->getCommentString() << " long double next halfword";
1121      O << '\n';
1122      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 16);
1123      if (VerboseAsm)
1124        O << '\t' << TAI->getCommentString() << " long double next halfword";
1125      O << '\n';
1126      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0]);
1127      if (VerboseAsm)
1128        O << '\t' << TAI->getCommentString()
1129          << " long double least significant halfword";
1130      O << '\n';
1131     } else {
1132      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0]);
1133      if (VerboseAsm)
1134        O << '\t' << TAI->getCommentString()
1135          << " long double least significant halfword of ~"
1136          << DoubleVal.convertToDouble();
1137      O << '\n';
1138      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 16);
1139      if (VerboseAsm)
1140        O << '\t' << TAI->getCommentString()
1141          << " long double next halfword";
1142      O << '\n';
1143      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 32);
1144      if (VerboseAsm)
1145        O << '\t' << TAI->getCommentString()
1146          << " long double next halfword";
1147      O << '\n';
1148      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 48);
1149      if (VerboseAsm)
1150        O << '\t' << TAI->getCommentString()
1151          << " long double next halfword";
1152      O << '\n';
1153      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[1]);
1154      if (VerboseAsm)
1155        O << '\t' << TAI->getCommentString()
1156          << " long double most significant halfword";
1157      O << '\n';
1158    }
1159    EmitZeros(TD->getTypeAllocSize(Type::X86_FP80Ty) -
1160              TD->getTypeStoreSize(Type::X86_FP80Ty), AddrSpace);
1161    return;
1162  } else if (CFP->getType() == Type::PPC_FP128Ty) {
1163    // all long double variants are printed as hex
1164    // api needed to prevent premature destruction
1165    APInt api = CFP->getValueAPF().bitcastToAPInt();
1166    const uint64_t *p = api.getRawData();
1167    if (TD->isBigEndian()) {
1168      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0] >> 32);
1169      if (VerboseAsm)
1170        O << '\t' << TAI->getCommentString()
1171          << " long double most significant word";
1172      O << '\n';
1173      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0]);
1174      if (VerboseAsm)
1175        O << '\t' << TAI->getCommentString()
1176        << " long double next word";
1177      O << '\n';
1178      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1] >> 32);
1179      if (VerboseAsm)
1180        O << '\t' << TAI->getCommentString()
1181          << " long double next word";
1182      O << '\n';
1183      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1]);
1184      if (VerboseAsm)
1185        O << '\t' << TAI->getCommentString()
1186          << " long double least significant word";
1187      O << '\n';
1188     } else {
1189      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1]);
1190      if (VerboseAsm)
1191        O << '\t' << TAI->getCommentString()
1192          << " long double least significant word";
1193      O << '\n';
1194      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1] >> 32);
1195      if (VerboseAsm)
1196        O << '\t' << TAI->getCommentString()
1197          << " long double next word";
1198      O << '\n';
1199      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0]);
1200      if (VerboseAsm)
1201        O << '\t' << TAI->getCommentString()
1202          << " long double next word";
1203      O << '\n';
1204      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0] >> 32);
1205      if (VerboseAsm)
1206        O << '\t' << TAI->getCommentString()
1207          << " long double most significant word";
1208      O << '\n';
1209    }
1210    return;
1211  } else assert(0 && "Floating point constant type not handled");
1212}
1213
1214void AsmPrinter::EmitGlobalConstantLargeInt(const ConstantInt *CI,
1215                                            unsigned AddrSpace) {
1216  const TargetData *TD = TM.getTargetData();
1217  unsigned BitWidth = CI->getBitWidth();
1218  assert(isPowerOf2_32(BitWidth) &&
1219         "Non-power-of-2-sized integers not handled!");
1220
1221  // We don't expect assemblers to support integer data directives
1222  // for more than 64 bits, so we emit the data in at most 64-bit
1223  // quantities at a time.
1224  const uint64_t *RawData = CI->getValue().getRawData();
1225  for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1226    uint64_t Val;
1227    if (TD->isBigEndian())
1228      Val = RawData[e - i - 1];
1229    else
1230      Val = RawData[i];
1231
1232    if (TAI->getData64bitsDirective(AddrSpace))
1233      O << TAI->getData64bitsDirective(AddrSpace) << Val << '\n';
1234    else if (TD->isBigEndian()) {
1235      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val >> 32);
1236      if (VerboseAsm)
1237        O << '\t' << TAI->getCommentString()
1238          << " Double-word most significant word " << Val;
1239      O << '\n';
1240      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val);
1241      if (VerboseAsm)
1242        O << '\t' << TAI->getCommentString()
1243          << " Double-word least significant word " << Val;
1244      O << '\n';
1245    } else {
1246      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val);
1247      if (VerboseAsm)
1248        O << '\t' << TAI->getCommentString()
1249          << " Double-word least significant word " << Val;
1250      O << '\n';
1251      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val >> 32);
1252      if (VerboseAsm)
1253        O << '\t' << TAI->getCommentString()
1254          << " Double-word most significant word " << Val;
1255      O << '\n';
1256    }
1257  }
1258}
1259
1260/// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1261void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1262  const TargetData *TD = TM.getTargetData();
1263  const Type *type = CV->getType();
1264  unsigned Size = TD->getTypeAllocSize(type);
1265
1266  if (CV->isNullValue() || isa<UndefValue>(CV)) {
1267    EmitZeros(Size, AddrSpace);
1268    return;
1269  } else if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) {
1270    EmitGlobalConstantArray(CVA , AddrSpace);
1271    return;
1272  } else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) {
1273    EmitGlobalConstantStruct(CVS, AddrSpace);
1274    return;
1275  } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) {
1276    EmitGlobalConstantFP(CFP, AddrSpace);
1277    return;
1278  } else if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1279    // Small integers are handled below; large integers are handled here.
1280    if (Size > 4) {
1281      EmitGlobalConstantLargeInt(CI, AddrSpace);
1282      return;
1283    }
1284  } else if (const ConstantVector *CP = dyn_cast<ConstantVector>(CV)) {
1285    EmitGlobalConstantVector(CP);
1286    return;
1287  }
1288
1289  printDataDirective(type, AddrSpace);
1290  EmitConstantValueOnly(CV);
1291  if (VerboseAsm) {
1292    if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1293      SmallString<40> S;
1294      CI->getValue().toStringUnsigned(S, 16);
1295      O << "\t\t\t" << TAI->getCommentString() << " 0x" << S.c_str();
1296    }
1297  }
1298  O << '\n';
1299}
1300
1301void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1302  // Target doesn't support this yet!
1303  abort();
1304}
1305
1306/// PrintSpecial - Print information related to the specified machine instr
1307/// that is independent of the operand, and may be independent of the instr
1308/// itself.  This can be useful for portably encoding the comment character
1309/// or other bits of target-specific knowledge into the asmstrings.  The
1310/// syntax used is ${:comment}.  Targets can override this to add support
1311/// for their own strange codes.
1312void AsmPrinter::PrintSpecial(const MachineInstr *MI, const char *Code) const {
1313  if (!strcmp(Code, "private")) {
1314    O << TAI->getPrivateGlobalPrefix();
1315  } else if (!strcmp(Code, "comment")) {
1316    if (VerboseAsm)
1317      O << TAI->getCommentString();
1318  } else if (!strcmp(Code, "uid")) {
1319    // Comparing the address of MI isn't sufficient, because machineinstrs may
1320    // be allocated to the same address across functions.
1321    const Function *ThisF = MI->getParent()->getParent()->getFunction();
1322
1323    // If this is a new LastFn instruction, bump the counter.
1324    if (LastMI != MI || LastFn != ThisF) {
1325      ++Counter;
1326      LastMI = MI;
1327      LastFn = ThisF;
1328    }
1329    O << Counter;
1330  } else {
1331    cerr << "Unknown special formatter '" << Code
1332         << "' for machine instr: " << *MI;
1333    exit(1);
1334  }
1335}
1336
1337/// processDebugLoc - Processes the debug information of each machine
1338/// instruction's DebugLoc.
1339void AsmPrinter::processDebugLoc(DebugLoc DL) {
1340  if (TAI->doesSupportDebugInformation() && DW->ShouldEmitDwarfDebug()) {
1341    if (!DL.isUnknown()) {
1342      DebugLocTuple CurDLT = MF->getDebugLocTuple(DL);
1343
1344      if (CurDLT.CompileUnit != 0 && PrevDLT != CurDLT)
1345        printLabel(DW->RecordSourceLine(CurDLT.Line, CurDLT.Col,
1346                                        DICompileUnit(CurDLT.CompileUnit)));
1347
1348      PrevDLT = CurDLT;
1349    }
1350  }
1351}
1352
1353/// printInlineAsm - This method formats and prints the specified machine
1354/// instruction that is an inline asm.
1355void AsmPrinter::printInlineAsm(const MachineInstr *MI) const {
1356  unsigned NumOperands = MI->getNumOperands();
1357
1358  // Count the number of register definitions.
1359  unsigned NumDefs = 0;
1360  for (; MI->getOperand(NumDefs).isReg() && MI->getOperand(NumDefs).isDef();
1361       ++NumDefs)
1362    assert(NumDefs != NumOperands-1 && "No asm string?");
1363
1364  assert(MI->getOperand(NumDefs).isSymbol() && "No asm string?");
1365
1366  // Disassemble the AsmStr, printing out the literal pieces, the operands, etc.
1367  const char *AsmStr = MI->getOperand(NumDefs).getSymbolName();
1368
1369  // If this asmstr is empty, just print the #APP/#NOAPP markers.
1370  // These are useful to see where empty asm's wound up.
1371  if (AsmStr[0] == 0) {
1372    O << TAI->getInlineAsmStart() << "\n\t" << TAI->getInlineAsmEnd() << '\n';
1373    return;
1374  }
1375
1376  O << TAI->getInlineAsmStart() << "\n\t";
1377
1378  // The variant of the current asmprinter.
1379  int AsmPrinterVariant = TAI->getAssemblerDialect();
1380
1381  int CurVariant = -1;            // The number of the {.|.|.} region we are in.
1382  const char *LastEmitted = AsmStr; // One past the last character emitted.
1383
1384  while (*LastEmitted) {
1385    switch (*LastEmitted) {
1386    default: {
1387      // Not a special case, emit the string section literally.
1388      const char *LiteralEnd = LastEmitted+1;
1389      while (*LiteralEnd && *LiteralEnd != '{' && *LiteralEnd != '|' &&
1390             *LiteralEnd != '}' && *LiteralEnd != '$' && *LiteralEnd != '\n')
1391        ++LiteralEnd;
1392      if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1393        O.write(LastEmitted, LiteralEnd-LastEmitted);
1394      LastEmitted = LiteralEnd;
1395      break;
1396    }
1397    case '\n':
1398      ++LastEmitted;   // Consume newline character.
1399      O << '\n';       // Indent code with newline.
1400      break;
1401    case '$': {
1402      ++LastEmitted;   // Consume '$' character.
1403      bool Done = true;
1404
1405      // Handle escapes.
1406      switch (*LastEmitted) {
1407      default: Done = false; break;
1408      case '$':     // $$ -> $
1409        if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1410          O << '$';
1411        ++LastEmitted;  // Consume second '$' character.
1412        break;
1413      case '(':             // $( -> same as GCC's { character.
1414        ++LastEmitted;      // Consume '(' character.
1415        if (CurVariant != -1) {
1416          cerr << "Nested variants found in inline asm string: '"
1417               << AsmStr << "'\n";
1418          exit(1);
1419        }
1420        CurVariant = 0;     // We're in the first variant now.
1421        break;
1422      case '|':
1423        ++LastEmitted;  // consume '|' character.
1424        if (CurVariant == -1)
1425          O << '|';       // this is gcc's behavior for | outside a variant
1426        else
1427          ++CurVariant;   // We're in the next variant.
1428        break;
1429      case ')':         // $) -> same as GCC's } char.
1430        ++LastEmitted;  // consume ')' character.
1431        if (CurVariant == -1)
1432          O << '}';     // this is gcc's behavior for } outside a variant
1433        else
1434          CurVariant = -1;
1435        break;
1436      }
1437      if (Done) break;
1438
1439      bool HasCurlyBraces = false;
1440      if (*LastEmitted == '{') {     // ${variable}
1441        ++LastEmitted;               // Consume '{' character.
1442        HasCurlyBraces = true;
1443      }
1444
1445      // If we have ${:foo}, then this is not a real operand reference, it is a
1446      // "magic" string reference, just like in .td files.  Arrange to call
1447      // PrintSpecial.
1448      if (HasCurlyBraces && *LastEmitted == ':') {
1449        ++LastEmitted;
1450        const char *StrStart = LastEmitted;
1451        const char *StrEnd = strchr(StrStart, '}');
1452        if (StrEnd == 0) {
1453          cerr << "Unterminated ${:foo} operand in inline asm string: '"
1454               << AsmStr << "'\n";
1455          exit(1);
1456        }
1457
1458        std::string Val(StrStart, StrEnd);
1459        PrintSpecial(MI, Val.c_str());
1460        LastEmitted = StrEnd+1;
1461        break;
1462      }
1463
1464      const char *IDStart = LastEmitted;
1465      char *IDEnd;
1466      errno = 0;
1467      long Val = strtol(IDStart, &IDEnd, 10); // We only accept numbers for IDs.
1468      if (!isdigit(*IDStart) || (Val == 0 && errno == EINVAL)) {
1469        cerr << "Bad $ operand number in inline asm string: '"
1470             << AsmStr << "'\n";
1471        exit(1);
1472      }
1473      LastEmitted = IDEnd;
1474
1475      char Modifier[2] = { 0, 0 };
1476
1477      if (HasCurlyBraces) {
1478        // If we have curly braces, check for a modifier character.  This
1479        // supports syntax like ${0:u}, which correspond to "%u0" in GCC asm.
1480        if (*LastEmitted == ':') {
1481          ++LastEmitted;    // Consume ':' character.
1482          if (*LastEmitted == 0) {
1483            cerr << "Bad ${:} expression in inline asm string: '"
1484                 << AsmStr << "'\n";
1485            exit(1);
1486          }
1487
1488          Modifier[0] = *LastEmitted;
1489          ++LastEmitted;    // Consume modifier character.
1490        }
1491
1492        if (*LastEmitted != '}') {
1493          cerr << "Bad ${} expression in inline asm string: '"
1494               << AsmStr << "'\n";
1495          exit(1);
1496        }
1497        ++LastEmitted;    // Consume '}' character.
1498      }
1499
1500      if ((unsigned)Val >= NumOperands-1) {
1501        cerr << "Invalid $ operand number in inline asm string: '"
1502             << AsmStr << "'\n";
1503        exit(1);
1504      }
1505
1506      // Okay, we finally have a value number.  Ask the target to print this
1507      // operand!
1508      if (CurVariant == -1 || CurVariant == AsmPrinterVariant) {
1509        unsigned OpNo = 1;
1510
1511        bool Error = false;
1512
1513        // Scan to find the machine operand number for the operand.
1514        for (; Val; --Val) {
1515          if (OpNo >= MI->getNumOperands()) break;
1516          unsigned OpFlags = MI->getOperand(OpNo).getImm();
1517          OpNo += InlineAsm::getNumOperandRegisters(OpFlags) + 1;
1518        }
1519
1520        if (OpNo >= MI->getNumOperands()) {
1521          Error = true;
1522        } else {
1523          unsigned OpFlags = MI->getOperand(OpNo).getImm();
1524          ++OpNo;  // Skip over the ID number.
1525
1526          if (Modifier[0]=='l')  // labels are target independent
1527            printBasicBlockLabel(MI->getOperand(OpNo).getMBB(),
1528                                 false, false, false);
1529          else {
1530            AsmPrinter *AP = const_cast<AsmPrinter*>(this);
1531            if ((OpFlags & 7) == 4) {
1532              Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant,
1533                                                Modifier[0] ? Modifier : 0);
1534            } else {
1535              Error = AP->PrintAsmOperand(MI, OpNo, AsmPrinterVariant,
1536                                          Modifier[0] ? Modifier : 0);
1537            }
1538          }
1539        }
1540        if (Error) {
1541          cerr << "Invalid operand found in inline asm: '"
1542               << AsmStr << "'\n";
1543          MI->dump();
1544          exit(1);
1545        }
1546      }
1547      break;
1548    }
1549    }
1550  }
1551  O << "\n\t" << TAI->getInlineAsmEnd() << '\n';
1552}
1553
1554/// printImplicitDef - This method prints the specified machine instruction
1555/// that is an implicit def.
1556void AsmPrinter::printImplicitDef(const MachineInstr *MI) const {
1557  if (VerboseAsm)
1558    O << '\t' << TAI->getCommentString() << " implicit-def: "
1559      << TRI->getAsmName(MI->getOperand(0).getReg()) << '\n';
1560}
1561
1562/// printLabel - This method prints a local label used by debug and
1563/// exception handling tables.
1564void AsmPrinter::printLabel(const MachineInstr *MI) const {
1565  printLabel(MI->getOperand(0).getImm());
1566}
1567
1568void AsmPrinter::printLabel(unsigned Id) const {
1569  O << TAI->getPrivateGlobalPrefix() << "label" << Id << ":\n";
1570}
1571
1572/// printDeclare - This method prints a local variable declaration used by
1573/// debug tables.
1574/// FIXME: It doesn't really print anything rather it inserts a DebugVariable
1575/// entry into dwarf table.
1576void AsmPrinter::printDeclare(const MachineInstr *MI) const {
1577  unsigned FI = MI->getOperand(0).getIndex();
1578  GlobalValue *GV = MI->getOperand(1).getGlobal();
1579  DW->RecordVariable(cast<GlobalVariable>(GV), FI, MI);
1580}
1581
1582/// PrintAsmOperand - Print the specified operand of MI, an INLINEASM
1583/// instruction, using the specified assembler variant.  Targets should
1584/// overried this to format as appropriate.
1585bool AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
1586                                 unsigned AsmVariant, const char *ExtraCode) {
1587  // Target doesn't support this yet!
1588  return true;
1589}
1590
1591bool AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
1592                                       unsigned AsmVariant,
1593                                       const char *ExtraCode) {
1594  // Target doesn't support this yet!
1595  return true;
1596}
1597
1598/// printBasicBlockLabel - This method prints the label for the specified
1599/// MachineBasicBlock
1600void AsmPrinter::printBasicBlockLabel(const MachineBasicBlock *MBB,
1601                                      bool printAlign,
1602                                      bool printColon,
1603                                      bool printComment) const {
1604  if (printAlign) {
1605    unsigned Align = MBB->getAlignment();
1606    if (Align)
1607      EmitAlignment(Log2_32(Align));
1608  }
1609
1610  O << TAI->getPrivateGlobalPrefix() << "BB" << getFunctionNumber() << '_'
1611    << MBB->getNumber();
1612  if (printColon)
1613    O << ':';
1614  if (printComment && MBB->getBasicBlock())
1615    O << '\t' << TAI->getCommentString() << ' '
1616      << MBB->getBasicBlock()->getNameStart();
1617}
1618
1619/// printPICJumpTableSetLabel - This method prints a set label for the
1620/// specified MachineBasicBlock for a jumptable entry.
1621void AsmPrinter::printPICJumpTableSetLabel(unsigned uid,
1622                                           const MachineBasicBlock *MBB) const {
1623  if (!TAI->getSetDirective())
1624    return;
1625
1626  O << TAI->getSetDirective() << ' ' << TAI->getPrivateGlobalPrefix()
1627    << getFunctionNumber() << '_' << uid << "_set_" << MBB->getNumber() << ',';
1628  printBasicBlockLabel(MBB, false, false, false);
1629  O << '-' << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
1630    << '_' << uid << '\n';
1631}
1632
1633void AsmPrinter::printPICJumpTableSetLabel(unsigned uid, unsigned uid2,
1634                                           const MachineBasicBlock *MBB) const {
1635  if (!TAI->getSetDirective())
1636    return;
1637
1638  O << TAI->getSetDirective() << ' ' << TAI->getPrivateGlobalPrefix()
1639    << getFunctionNumber() << '_' << uid << '_' << uid2
1640    << "_set_" << MBB->getNumber() << ',';
1641  printBasicBlockLabel(MBB, false, false, false);
1642  O << '-' << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
1643    << '_' << uid << '_' << uid2 << '\n';
1644}
1645
1646/// printDataDirective - This method prints the asm directive for the
1647/// specified type.
1648void AsmPrinter::printDataDirective(const Type *type, unsigned AddrSpace) {
1649  const TargetData *TD = TM.getTargetData();
1650  switch (type->getTypeID()) {
1651  case Type::IntegerTyID: {
1652    unsigned BitWidth = cast<IntegerType>(type)->getBitWidth();
1653    if (BitWidth <= 8)
1654      O << TAI->getData8bitsDirective(AddrSpace);
1655    else if (BitWidth <= 16)
1656      O << TAI->getData16bitsDirective(AddrSpace);
1657    else if (BitWidth <= 32)
1658      O << TAI->getData32bitsDirective(AddrSpace);
1659    else if (BitWidth <= 64) {
1660      assert(TAI->getData64bitsDirective(AddrSpace) &&
1661             "Target cannot handle 64-bit constant exprs!");
1662      O << TAI->getData64bitsDirective(AddrSpace);
1663    } else {
1664      assert(0 && "Target cannot handle given data directive width!");
1665    }
1666    break;
1667  }
1668  case Type::PointerTyID:
1669    if (TD->getPointerSize() == 8) {
1670      assert(TAI->getData64bitsDirective(AddrSpace) &&
1671             "Target cannot handle 64-bit pointer exprs!");
1672      O << TAI->getData64bitsDirective(AddrSpace);
1673    } else if (TD->getPointerSize() == 2) {
1674      O << TAI->getData16bitsDirective(AddrSpace);
1675    } else if (TD->getPointerSize() == 1) {
1676      O << TAI->getData8bitsDirective(AddrSpace);
1677    } else {
1678      O << TAI->getData32bitsDirective(AddrSpace);
1679    }
1680    break;
1681  case Type::FloatTyID: case Type::DoubleTyID:
1682  case Type::X86_FP80TyID: case Type::FP128TyID: case Type::PPC_FP128TyID:
1683    assert (0 && "Should have already output floating point constant.");
1684  default:
1685    assert (0 && "Can't handle printing this type of thing");
1686    break;
1687  }
1688}
1689
1690void AsmPrinter::printSuffixedName(const char *Name, const char *Suffix,
1691                                   const char *Prefix) {
1692  if (Name[0]=='\"')
1693    O << '\"';
1694  O << TAI->getPrivateGlobalPrefix();
1695  if (Prefix) O << Prefix;
1696  if (Name[0]=='\"')
1697    O << '\"';
1698  if (Name[0]=='\"')
1699    O << Name[1];
1700  else
1701    O << Name;
1702  O << Suffix;
1703  if (Name[0]=='\"')
1704    O << '\"';
1705}
1706
1707void AsmPrinter::printSuffixedName(const std::string &Name, const char* Suffix) {
1708  printSuffixedName(Name.c_str(), Suffix);
1709}
1710
1711void AsmPrinter::printVisibility(const std::string& Name,
1712                                 unsigned Visibility) const {
1713  if (Visibility == GlobalValue::HiddenVisibility) {
1714    if (const char *Directive = TAI->getHiddenDirective())
1715      O << Directive << Name << '\n';
1716  } else if (Visibility == GlobalValue::ProtectedVisibility) {
1717    if (const char *Directive = TAI->getProtectedDirective())
1718      O << Directive << Name << '\n';
1719  }
1720}
1721
1722void AsmPrinter::printOffset(int64_t Offset) const {
1723  if (Offset > 0)
1724    O << '+' << Offset;
1725  else if (Offset < 0)
1726    O << Offset;
1727}
1728
1729GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1730  if (!S->usesMetadata())
1731    return 0;
1732
1733  gcp_iterator GCPI = GCMetadataPrinters.find(S);
1734  if (GCPI != GCMetadataPrinters.end())
1735    return GCPI->second;
1736
1737  const char *Name = S->getName().c_str();
1738
1739  for (GCMetadataPrinterRegistry::iterator
1740         I = GCMetadataPrinterRegistry::begin(),
1741         E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1742    if (strcmp(Name, I->getName()) == 0) {
1743      GCMetadataPrinter *GMP = I->instantiate();
1744      GMP->S = S;
1745      GCMetadataPrinters.insert(std::make_pair(S, GMP));
1746      return GMP;
1747    }
1748
1749  cerr << "no GCMetadataPrinter registered for GC: " << Name << "\n";
1750  abort();
1751}
1752