AsmPrinter.cpp revision 3f997f8f132bb391d17ac2bf2db4009338783c07 
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)
49{
50  switch (AsmVerbose) {
51  case cl::BOU_UNSET: VerboseAsm = VDef;  break;
52  case cl::BOU_TRUE:  VerboseAsm = true;  break;
53  case cl::BOU_FALSE: VerboseAsm = false; break;
54  }
55}
56
57AsmPrinter::~AsmPrinter() {
58  for (gcp_iterator I = GCMetadataPrinters.begin(),
59                    E = GCMetadataPrinters.end(); I != E; ++I)
60    delete I->second;
61}
62
63/// SwitchToTextSection - Switch to the specified text section of the executable
64/// if we are not already in it!
65///
66void AsmPrinter::SwitchToTextSection(const char *NewSection,
67                                     const GlobalValue *GV) {
68  std::string NS;
69  if (GV && GV->hasSection())
70    NS = TAI->getSwitchToSectionDirective() + GV->getSection();
71  else
72    NS = NewSection;
73
74  // If we're already in this section, we're done.
75  if (CurrentSection == NS) return;
76
77  // Close the current section, if applicable.
78  if (TAI->getSectionEndDirectiveSuffix() && !CurrentSection.empty())
79    O << CurrentSection << TAI->getSectionEndDirectiveSuffix() << '\n';
80
81  CurrentSection = NS;
82
83  if (!CurrentSection.empty())
84    O << CurrentSection << TAI->getTextSectionStartSuffix() << '\n';
85
86  IsInTextSection = true;
87}
88
89/// SwitchToDataSection - Switch to the specified data section of the executable
90/// if we are not already in it!
91///
92void AsmPrinter::SwitchToDataSection(const char *NewSection,
93                                     const GlobalValue *GV) {
94  std::string NS;
95  if (GV && GV->hasSection())
96    NS = TAI->getSwitchToSectionDirective() + GV->getSection();
97  else
98    NS = NewSection;
99
100  // If we're already in this section, we're done.
101  if (CurrentSection == NS) return;
102
103  // Close the current section, if applicable.
104  if (TAI->getSectionEndDirectiveSuffix() && !CurrentSection.empty())
105    O << CurrentSection << TAI->getSectionEndDirectiveSuffix() << '\n';
106
107  CurrentSection = NS;
108
109  if (!CurrentSection.empty())
110    O << CurrentSection << TAI->getDataSectionStartSuffix() << '\n';
111
112  IsInTextSection = false;
113}
114
115/// SwitchToSection - Switch to the specified section of the executable if we
116/// are not already in it!
117void AsmPrinter::SwitchToSection(const Section* NS) {
118  const std::string& NewSection = NS->getName();
119
120  // If we're already in this section, we're done.
121  if (CurrentSection == NewSection) return;
122
123  // Close the current section, if applicable.
124  if (TAI->getSectionEndDirectiveSuffix() && !CurrentSection.empty())
125    O << CurrentSection << TAI->getSectionEndDirectiveSuffix() << '\n';
126
127  // FIXME: Make CurrentSection a Section* in the future
128  CurrentSection = NewSection;
129  CurrentSection_ = NS;
130
131  if (!CurrentSection.empty()) {
132    // If section is named we need to switch into it via special '.section'
133    // directive and also append funky flags. Otherwise - section name is just
134    // some magic assembler directive.
135    if (NS->isNamed())
136      O << TAI->getSwitchToSectionDirective()
137        << CurrentSection
138        << TAI->getSectionFlags(NS->getFlags());
139    else
140      O << CurrentSection;
141    O << TAI->getDataSectionStartSuffix() << '\n';
142  }
143
144  IsInTextSection = (NS->getFlags() & SectionFlags::Code);
145}
146
147void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
148  MachineFunctionPass::getAnalysisUsage(AU);
149  AU.addRequired<GCModuleInfo>();
150}
151
152bool AsmPrinter::doInitialization(Module &M) {
153  Mang = new Mangler(M, TAI->getGlobalPrefix(), TAI->getPrivateGlobalPrefix());
154
155  GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
156  assert(MI && "AsmPrinter didn't require GCModuleInfo?");
157
158  if (TAI->hasSingleParameterDotFile()) {
159    /* Very minimal debug info. It is ignored if we emit actual
160       debug info. If we don't, this at helps the user find where
161       a function came from. */
162    O << "\t.file\t\"" << M.getModuleIdentifier() << "\"\n";
163  }
164
165  for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
166    if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
167      MP->beginAssembly(O, *this, *TAI);
168
169  if (!M.getModuleInlineAsm().empty())
170    O << TAI->getCommentString() << " Start of file scope inline assembly\n"
171      << M.getModuleInlineAsm()
172      << '\n' << TAI->getCommentString()
173      << " End of file scope inline assembly\n";
174
175  SwitchToDataSection("");   // Reset back to no section.
176
177  MachineModuleInfo *MMI = getAnalysisIfAvailable<MachineModuleInfo>();
178  if (MMI) MMI->AnalyzeModule(M);
179  DW = getAnalysisIfAvailable<DwarfWriter>();
180  return false;
181}
182
183bool AsmPrinter::doFinalization(Module &M) {
184  if (TAI->getWeakRefDirective()) {
185    if (!ExtWeakSymbols.empty())
186      SwitchToDataSection("");
187
188    for (std::set<const GlobalValue*>::iterator i = ExtWeakSymbols.begin(),
189         e = ExtWeakSymbols.end(); i != e; ++i)
190      O << TAI->getWeakRefDirective() << Mang->getValueName(*i) << '\n';
191  }
192
193  if (TAI->getSetDirective()) {
194    if (!M.alias_empty())
195      SwitchToSection(TAI->getTextSection());
196
197    O << '\n';
198    for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
199         I!=E; ++I) {
200      std::string Name = Mang->getValueName(I);
201      std::string Target;
202
203      const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
204      Target = Mang->getValueName(GV);
205
206      if (I->hasExternalLinkage() || !TAI->getWeakRefDirective())
207        O << "\t.globl\t" << Name << '\n';
208      else if (I->hasWeakLinkage())
209        O << TAI->getWeakRefDirective() << Name << '\n';
210      else if (!I->hasLocalLinkage())
211        assert(0 && "Invalid alias linkage");
212
213      printVisibility(Name, I->getVisibility());
214
215      O << TAI->getSetDirective() << ' ' << Name << ", " << Target << '\n';
216    }
217  }
218
219  GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
220  assert(MI && "AsmPrinter didn't require GCModuleInfo?");
221  for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
222    if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
223      MP->finishAssembly(O, *this, *TAI);
224
225  // If we don't have any trampolines, then we don't require stack memory
226  // to be executable. Some targets have a directive to declare this.
227  Function* InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
228  if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
229    if (TAI->getNonexecutableStackDirective())
230      O << TAI->getNonexecutableStackDirective() << '\n';
231
232  delete Mang; Mang = 0;
233  return false;
234}
235
236const std::string &
237AsmPrinter::getCurrentFunctionEHName(const MachineFunction *MF,
238                                     std::string &Name) const {
239  assert(MF && "No machine function?");
240  Name = MF->getFunction()->getName();
241  if (Name.empty())
242    Name = Mang->getValueName(MF->getFunction());
243  Name = Mang->makeNameProper(TAI->getEHGlobalPrefix() +
244                              Name + ".eh", TAI->getGlobalPrefix());
245  return Name;
246}
247
248void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
249  // What's my mangled name?
250  CurrentFnName = Mang->getValueName(MF.getFunction());
251  IncrementFunctionNumber();
252}
253
254namespace {
255  // SectionCPs - Keep track the alignment, constpool entries per Section.
256  struct SectionCPs {
257    const Section *S;
258    unsigned Alignment;
259    SmallVector<unsigned, 4> CPEs;
260    SectionCPs(const Section *s, unsigned a) : S(s), Alignment(a) {};
261  };
262}
263
264/// EmitConstantPool - Print to the current output stream assembly
265/// representations of the constants in the constant pool MCP. This is
266/// used to print out constants which have been "spilled to memory" by
267/// the code generator.
268///
269void AsmPrinter::EmitConstantPool(MachineConstantPool *MCP) {
270  const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
271  if (CP.empty()) return;
272
273  // Calculate sections for constant pool entries. We collect entries to go into
274  // the same section together to reduce amount of section switch statements.
275  SmallVector<SectionCPs, 4> CPSections;
276  for (unsigned i = 0, e = CP.size(); i != e; ++i) {
277    MachineConstantPoolEntry CPE = CP[i];
278    unsigned Align = CPE.getAlignment();
279    const Section* S = TAI->SelectSectionForMachineConst(CPE.getType());
280    // The number of sections are small, just do a linear search from the
281    // last section to the first.
282    bool Found = false;
283    unsigned SecIdx = CPSections.size();
284    while (SecIdx != 0) {
285      if (CPSections[--SecIdx].S == S) {
286        Found = true;
287        break;
288      }
289    }
290    if (!Found) {
291      SecIdx = CPSections.size();
292      CPSections.push_back(SectionCPs(S, Align));
293    }
294
295    if (Align > CPSections[SecIdx].Alignment)
296      CPSections[SecIdx].Alignment = Align;
297    CPSections[SecIdx].CPEs.push_back(i);
298  }
299
300  // Now print stuff into the calculated sections.
301  for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
302    SwitchToSection(CPSections[i].S);
303    EmitAlignment(Log2_32(CPSections[i].Alignment));
304
305    unsigned Offset = 0;
306    for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
307      unsigned CPI = CPSections[i].CPEs[j];
308      MachineConstantPoolEntry CPE = CP[CPI];
309
310      // Emit inter-object padding for alignment.
311      unsigned AlignMask = CPE.getAlignment() - 1;
312      unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
313      EmitZeros(NewOffset - Offset);
314
315      const Type *Ty = CPE.getType();
316      Offset = NewOffset + TM.getTargetData()->getTypePaddedSize(Ty);
317
318      O << TAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << '_'
319        << CPI << ":\t\t\t\t\t";
320      if (VerboseAsm) {
321        O << TAI->getCommentString() << ' ';
322        WriteTypeSymbolic(O, CPE.getType(), 0);
323      }
324      O << '\n';
325      if (CPE.isMachineConstantPoolEntry())
326        EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
327      else
328        EmitGlobalConstant(CPE.Val.ConstVal);
329    }
330  }
331}
332
333/// EmitJumpTableInfo - Print assembly representations of the jump tables used
334/// by the current function to the current output stream.
335///
336void AsmPrinter::EmitJumpTableInfo(MachineJumpTableInfo *MJTI,
337                                   MachineFunction &MF) {
338  const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
339  if (JT.empty()) return;
340
341  bool IsPic = TM.getRelocationModel() == Reloc::PIC_;
342
343  // Pick the directive to use to print the jump table entries, and switch to
344  // the appropriate section.
345  TargetLowering *LoweringInfo = TM.getTargetLowering();
346
347  const char* JumpTableDataSection = TAI->getJumpTableDataSection();
348  const Function *F = MF.getFunction();
349  unsigned SectionFlags = TAI->SectionFlagsForGlobal(F);
350  if ((IsPic && !(LoweringInfo && LoweringInfo->usesGlobalOffsetTable())) ||
351     !JumpTableDataSection ||
352      SectionFlags & SectionFlags::Linkonce) {
353    // In PIC mode, we need to emit the jump table to the same section as the
354    // function body itself, otherwise the label differences won't make sense.
355    // We should also do if the section name is NULL or function is declared in
356    // discardable section.
357    SwitchToSection(TAI->SectionForGlobal(F));
358  } else {
359    SwitchToDataSection(JumpTableDataSection);
360  }
361
362  EmitAlignment(Log2_32(MJTI->getAlignment()));
363
364  for (unsigned i = 0, e = JT.size(); i != e; ++i) {
365    const std::vector<MachineBasicBlock*> &JTBBs = JT[i].MBBs;
366
367    // If this jump table was deleted, ignore it.
368    if (JTBBs.empty()) continue;
369
370    // For PIC codegen, if possible we want to use the SetDirective to reduce
371    // the number of relocations the assembler will generate for the jump table.
372    // Set directives are all printed before the jump table itself.
373    SmallPtrSet<MachineBasicBlock*, 16> EmittedSets;
374    if (TAI->getSetDirective() && IsPic)
375      for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
376        if (EmittedSets.insert(JTBBs[ii]))
377          printPICJumpTableSetLabel(i, JTBBs[ii]);
378
379    // On some targets (e.g. darwin) we want to emit two consequtive labels
380    // before each jump table.  The first label is never referenced, but tells
381    // the assembler and linker the extents of the jump table object.  The
382    // second label is actually referenced by the code.
383    if (const char *JTLabelPrefix = TAI->getJumpTableSpecialLabelPrefix())
384      O << JTLabelPrefix << "JTI" << getFunctionNumber() << '_' << i << ":\n";
385
386    O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
387      << '_' << i << ":\n";
388
389    for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
390      printPICJumpTableEntry(MJTI, JTBBs[ii], i);
391      O << '\n';
392    }
393  }
394}
395
396void AsmPrinter::printPICJumpTableEntry(const MachineJumpTableInfo *MJTI,
397                                        const MachineBasicBlock *MBB,
398                                        unsigned uid)  const {
399  bool IsPic = TM.getRelocationModel() == Reloc::PIC_;
400
401  // Use JumpTableDirective otherwise honor the entry size from the jump table
402  // info.
403  const char *JTEntryDirective = TAI->getJumpTableDirective();
404  bool HadJTEntryDirective = JTEntryDirective != NULL;
405  if (!HadJTEntryDirective) {
406    JTEntryDirective = MJTI->getEntrySize() == 4 ?
407      TAI->getData32bitsDirective() : TAI->getData64bitsDirective();
408  }
409
410  O << JTEntryDirective << ' ';
411
412  // If we have emitted set directives for the jump table entries, print
413  // them rather than the entries themselves.  If we're emitting PIC, then
414  // emit the table entries as differences between two text section labels.
415  // If we're emitting non-PIC code, then emit the entries as direct
416  // references to the target basic blocks.
417  if (IsPic) {
418    if (TAI->getSetDirective()) {
419      O << TAI->getPrivateGlobalPrefix() << getFunctionNumber()
420        << '_' << uid << "_set_" << MBB->getNumber();
421    } else {
422      printBasicBlockLabel(MBB, false, false, false);
423      // If the arch uses custom Jump Table directives, don't calc relative to
424      // JT
425      if (!HadJTEntryDirective)
426        O << '-' << TAI->getPrivateGlobalPrefix() << "JTI"
427          << getFunctionNumber() << '_' << uid;
428    }
429  } else {
430    printBasicBlockLabel(MBB, false, false, false);
431  }
432}
433
434
435/// EmitSpecialLLVMGlobal - Check to see if the specified global is a
436/// special global used by LLVM.  If so, emit it and return true, otherwise
437/// do nothing and return false.
438bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
439  if (GV->getName() == "llvm.used") {
440    if (TAI->getUsedDirective() != 0)    // No need to emit this at all.
441      EmitLLVMUsedList(GV->getInitializer());
442    return true;
443  }
444
445  // Ignore debug and non-emitted data.
446  if (GV->getSection() == "llvm.metadata" ||
447      GV->hasAvailableExternallyLinkage())
448    return true;
449
450  if (!GV->hasAppendingLinkage()) return false;
451
452  assert(GV->hasInitializer() && "Not a special LLVM global!");
453
454  const TargetData *TD = TM.getTargetData();
455  unsigned Align = Log2_32(TD->getPointerPrefAlignment());
456  if (GV->getName() == "llvm.global_ctors") {
457    SwitchToDataSection(TAI->getStaticCtorsSection());
458    EmitAlignment(Align, 0);
459    EmitXXStructorList(GV->getInitializer());
460    return true;
461  }
462
463  if (GV->getName() == "llvm.global_dtors") {
464    SwitchToDataSection(TAI->getStaticDtorsSection());
465    EmitAlignment(Align, 0);
466    EmitXXStructorList(GV->getInitializer());
467    return true;
468  }
469
470  return false;
471}
472
473/// findGlobalValue - if CV is an expression equivalent to a single
474/// global value, return that value.
475const GlobalValue * AsmPrinter::findGlobalValue(const Constant *CV) {
476  if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
477    return GV;
478  else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
479    const TargetData *TD = TM.getTargetData();
480    unsigned Opcode = CE->getOpcode();
481    switch (Opcode) {
482    case Instruction::GetElementPtr: {
483      const Constant *ptrVal = CE->getOperand(0);
484      SmallVector<Value*, 8> idxVec(CE->op_begin()+1, CE->op_end());
485      if (TD->getIndexedOffset(ptrVal->getType(), &idxVec[0], idxVec.size()))
486        return 0;
487      return findGlobalValue(ptrVal);
488    }
489    case Instruction::BitCast:
490      return findGlobalValue(CE->getOperand(0));
491    default:
492      return 0;
493    }
494  }
495  return 0;
496}
497
498/// EmitLLVMUsedList - For targets that define a TAI::UsedDirective, mark each
499/// global in the specified llvm.used list for which emitUsedDirectiveFor
500/// is true, as being used with this directive.
501
502void AsmPrinter::EmitLLVMUsedList(Constant *List) {
503  const char *Directive = TAI->getUsedDirective();
504
505  // Should be an array of 'sbyte*'.
506  ConstantArray *InitList = dyn_cast<ConstantArray>(List);
507  if (InitList == 0) return;
508
509  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
510    const GlobalValue *GV = findGlobalValue(InitList->getOperand(i));
511    if (TAI->emitUsedDirectiveFor(GV, Mang)) {
512      O << Directive;
513      EmitConstantValueOnly(InitList->getOperand(i));
514      O << '\n';
515    }
516  }
517}
518
519/// EmitXXStructorList - Emit the ctor or dtor list.  This just prints out the
520/// function pointers, ignoring the init priority.
521void AsmPrinter::EmitXXStructorList(Constant *List) {
522  // Should be an array of '{ int, void ()* }' structs.  The first value is the
523  // init priority, which we ignore.
524  if (!isa<ConstantArray>(List)) return;
525  ConstantArray *InitList = cast<ConstantArray>(List);
526  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
527    if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
528      if (CS->getNumOperands() != 2) return;  // Not array of 2-element structs.
529
530      if (CS->getOperand(1)->isNullValue())
531        return;  // Found a null terminator, exit printing.
532      // Emit the function pointer.
533      EmitGlobalConstant(CS->getOperand(1));
534    }
535}
536
537/// getGlobalLinkName - Returns the asm/link name of of the specified
538/// global variable.  Should be overridden by each target asm printer to
539/// generate the appropriate value.
540const std::string &AsmPrinter::getGlobalLinkName(const GlobalVariable *GV,
541                                                 std::string &LinkName) const {
542  if (isa<Function>(GV)) {
543    LinkName += TAI->getFunctionAddrPrefix();
544    LinkName += Mang->getValueName(GV);
545    LinkName += TAI->getFunctionAddrSuffix();
546  } else {
547    LinkName += TAI->getGlobalVarAddrPrefix();
548    LinkName += Mang->getValueName(GV);
549    LinkName += TAI->getGlobalVarAddrSuffix();
550  }
551
552  return LinkName;
553}
554
555/// EmitExternalGlobal - Emit the external reference to a global variable.
556/// Should be overridden if an indirect reference should be used.
557void AsmPrinter::EmitExternalGlobal(const GlobalVariable *GV) {
558  std::string GLN;
559  O << getGlobalLinkName(GV, GLN);
560}
561
562
563
564//===----------------------------------------------------------------------===//
565/// LEB 128 number encoding.
566
567/// PrintULEB128 - Print a series of hexidecimal values (separated by commas)
568/// representing an unsigned leb128 value.
569void AsmPrinter::PrintULEB128(unsigned Value) const {
570  char Buffer[20];
571  do {
572    unsigned char Byte = static_cast<unsigned char>(Value & 0x7f);
573    Value >>= 7;
574    if (Value) Byte |= 0x80;
575    O << "0x" << utohex_buffer(Byte, Buffer+20);
576    if (Value) O << ", ";
577  } while (Value);
578}
579
580/// PrintSLEB128 - Print a series of hexidecimal values (separated by commas)
581/// representing a signed leb128 value.
582void AsmPrinter::PrintSLEB128(int Value) const {
583  int Sign = Value >> (8 * sizeof(Value) - 1);
584  bool IsMore;
585  char Buffer[20];
586
587  do {
588    unsigned char Byte = static_cast<unsigned char>(Value & 0x7f);
589    Value >>= 7;
590    IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0;
591    if (IsMore) Byte |= 0x80;
592    O << "0x" << utohex_buffer(Byte, Buffer+20);
593    if (IsMore) O << ", ";
594  } while (IsMore);
595}
596
597//===--------------------------------------------------------------------===//
598// Emission and print routines
599//
600
601/// PrintHex - Print a value as a hexidecimal value.
602///
603void AsmPrinter::PrintHex(int Value) const {
604  char Buffer[20];
605  O << "0x" << utohex_buffer(static_cast<unsigned>(Value), Buffer+20);
606}
607
608/// EOL - Print a newline character to asm stream.  If a comment is present
609/// then it will be printed first.  Comments should not contain '\n'.
610void AsmPrinter::EOL() const {
611  O << '\n';
612}
613
614void AsmPrinter::EOL(const std::string &Comment) const {
615  if (VerboseAsm && !Comment.empty()) {
616    O << '\t'
617      << TAI->getCommentString()
618      << ' '
619      << Comment;
620  }
621  O << '\n';
622}
623
624void AsmPrinter::EOL(const char* Comment) const {
625  if (VerboseAsm && *Comment) {
626    O << '\t'
627      << TAI->getCommentString()
628      << ' '
629      << Comment;
630  }
631  O << '\n';
632}
633
634/// EmitULEB128Bytes - Emit an assembler byte data directive to compose an
635/// unsigned leb128 value.
636void AsmPrinter::EmitULEB128Bytes(unsigned Value) const {
637  if (TAI->hasLEB128()) {
638    O << "\t.uleb128\t"
639      << Value;
640  } else {
641    O << TAI->getData8bitsDirective();
642    PrintULEB128(Value);
643  }
644}
645
646/// EmitSLEB128Bytes - print an assembler byte data directive to compose a
647/// signed leb128 value.
648void AsmPrinter::EmitSLEB128Bytes(int Value) const {
649  if (TAI->hasLEB128()) {
650    O << "\t.sleb128\t"
651      << Value;
652  } else {
653    O << TAI->getData8bitsDirective();
654    PrintSLEB128(Value);
655  }
656}
657
658/// EmitInt8 - Emit a byte directive and value.
659///
660void AsmPrinter::EmitInt8(int Value) const {
661  O << TAI->getData8bitsDirective();
662  PrintHex(Value & 0xFF);
663}
664
665/// EmitInt16 - Emit a short directive and value.
666///
667void AsmPrinter::EmitInt16(int Value) const {
668  O << TAI->getData16bitsDirective();
669  PrintHex(Value & 0xFFFF);
670}
671
672/// EmitInt32 - Emit a long directive and value.
673///
674void AsmPrinter::EmitInt32(int Value) const {
675  O << TAI->getData32bitsDirective();
676  PrintHex(Value);
677}
678
679/// EmitInt64 - Emit a long long directive and value.
680///
681void AsmPrinter::EmitInt64(uint64_t Value) const {
682  if (TAI->getData64bitsDirective()) {
683    O << TAI->getData64bitsDirective();
684    PrintHex(Value);
685  } else {
686    if (TM.getTargetData()->isBigEndian()) {
687      EmitInt32(unsigned(Value >> 32)); O << '\n';
688      EmitInt32(unsigned(Value));
689    } else {
690      EmitInt32(unsigned(Value)); O << '\n';
691      EmitInt32(unsigned(Value >> 32));
692    }
693  }
694}
695
696/// toOctal - Convert the low order bits of X into an octal digit.
697///
698static inline char toOctal(int X) {
699  return (X&7)+'0';
700}
701
702/// printStringChar - Print a char, escaped if necessary.
703///
704static void printStringChar(raw_ostream &O, unsigned char C) {
705  if (C == '"') {
706    O << "\\\"";
707  } else if (C == '\\') {
708    O << "\\\\";
709  } else if (isprint((unsigned char)C)) {
710    O << C;
711  } else {
712    switch(C) {
713    case '\b': O << "\\b"; break;
714    case '\f': O << "\\f"; break;
715    case '\n': O << "\\n"; break;
716    case '\r': O << "\\r"; break;
717    case '\t': O << "\\t"; break;
718    default:
719      O << '\\';
720      O << toOctal(C >> 6);
721      O << toOctal(C >> 3);
722      O << toOctal(C >> 0);
723      break;
724    }
725  }
726}
727
728/// EmitString - Emit a string with quotes and a null terminator.
729/// Special characters are emitted properly.
730/// \literal (Eg. '\t') \endliteral
731void AsmPrinter::EmitString(const std::string &String) const {
732  EmitString(String.c_str(), String.size());
733}
734
735void AsmPrinter::EmitString(const char *String, unsigned Size) const {
736  const char* AscizDirective = TAI->getAscizDirective();
737  if (AscizDirective)
738    O << AscizDirective;
739  else
740    O << TAI->getAsciiDirective();
741  O << '\"';
742  for (unsigned i = 0; i < Size; ++i)
743    printStringChar(O, String[i]);
744  if (AscizDirective)
745    O << '\"';
746  else
747    O << "\\0\"";
748}
749
750
751/// EmitFile - Emit a .file directive.
752void AsmPrinter::EmitFile(unsigned Number, const std::string &Name) const {
753  O << "\t.file\t" << Number << " \"";
754  for (unsigned i = 0, N = Name.size(); i < N; ++i)
755    printStringChar(O, Name[i]);
756  O << '\"';
757}
758
759
760//===----------------------------------------------------------------------===//
761
762// EmitAlignment - Emit an alignment directive to the specified power of
763// two boundary.  For example, if you pass in 3 here, you will get an 8
764// byte alignment.  If a global value is specified, and if that global has
765// an explicit alignment requested, it will unconditionally override the
766// alignment request.  However, if ForcedAlignBits is specified, this value
767// has final say: the ultimate alignment will be the max of ForcedAlignBits
768// and the alignment computed with NumBits and the global.
769//
770// The algorithm is:
771//     Align = NumBits;
772//     if (GV && GV->hasalignment) Align = GV->getalignment();
773//     Align = std::max(Align, ForcedAlignBits);
774//
775void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
776                               unsigned ForcedAlignBits,
777                               bool UseFillExpr) const {
778  if (GV && GV->getAlignment())
779    NumBits = Log2_32(GV->getAlignment());
780  NumBits = std::max(NumBits, ForcedAlignBits);
781
782  if (NumBits == 0) return;   // No need to emit alignment.
783  if (TAI->getAlignmentIsInBytes()) NumBits = 1 << NumBits;
784  O << TAI->getAlignDirective() << NumBits;
785
786  unsigned FillValue = TAI->getTextAlignFillValue();
787  UseFillExpr &= IsInTextSection && FillValue;
788  if (UseFillExpr) {
789    O << ',';
790    PrintHex(FillValue);
791  }
792  O << '\n';
793}
794
795
796/// EmitZeros - Emit a block of zeros.
797///
798void AsmPrinter::EmitZeros(uint64_t NumZeros, unsigned AddrSpace) const {
799  if (NumZeros) {
800    if (TAI->getZeroDirective()) {
801      O << TAI->getZeroDirective() << NumZeros;
802      if (TAI->getZeroDirectiveSuffix())
803        O << TAI->getZeroDirectiveSuffix();
804      O << '\n';
805    } else {
806      for (; NumZeros; --NumZeros)
807        O << TAI->getData8bitsDirective(AddrSpace) << "0\n";
808    }
809  }
810}
811
812// Print out the specified constant, without a storage class.  Only the
813// constants valid in constant expressions can occur here.
814void AsmPrinter::EmitConstantValueOnly(const Constant *CV) {
815  if (CV->isNullValue() || isa<UndefValue>(CV))
816    O << '0';
817  else if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
818    O << CI->getZExtValue();
819  } else if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV)) {
820    // This is a constant address for a global variable or function. Use the
821    // name of the variable or function as the address value, possibly
822    // decorating it with GlobalVarAddrPrefix/Suffix or
823    // FunctionAddrPrefix/Suffix (these all default to "" )
824    if (isa<Function>(GV)) {
825      O << TAI->getFunctionAddrPrefix()
826        << Mang->getValueName(GV)
827        << TAI->getFunctionAddrSuffix();
828    } else {
829      O << TAI->getGlobalVarAddrPrefix()
830        << Mang->getValueName(GV)
831        << TAI->getGlobalVarAddrSuffix();
832    }
833  } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
834    const TargetData *TD = TM.getTargetData();
835    unsigned Opcode = CE->getOpcode();
836    switch (Opcode) {
837    case Instruction::GetElementPtr: {
838      // generate a symbolic expression for the byte address
839      const Constant *ptrVal = CE->getOperand(0);
840      SmallVector<Value*, 8> idxVec(CE->op_begin()+1, CE->op_end());
841      if (int64_t Offset = TD->getIndexedOffset(ptrVal->getType(), &idxVec[0],
842                                                idxVec.size())) {
843        // Truncate/sext the offset to the pointer size.
844        if (TD->getPointerSizeInBits() != 64) {
845          int SExtAmount = 64-TD->getPointerSizeInBits();
846          Offset = (Offset << SExtAmount) >> SExtAmount;
847        }
848
849        if (Offset)
850          O << '(';
851        EmitConstantValueOnly(ptrVal);
852        if (Offset > 0)
853          O << ") + " << Offset;
854        else if (Offset < 0)
855          O << ") - " << -Offset;
856      } else {
857        EmitConstantValueOnly(ptrVal);
858      }
859      break;
860    }
861    case Instruction::Trunc:
862    case Instruction::ZExt:
863    case Instruction::SExt:
864    case Instruction::FPTrunc:
865    case Instruction::FPExt:
866    case Instruction::UIToFP:
867    case Instruction::SIToFP:
868    case Instruction::FPToUI:
869    case Instruction::FPToSI:
870      assert(0 && "FIXME: Don't yet support this kind of constant cast expr");
871      break;
872    case Instruction::BitCast:
873      return EmitConstantValueOnly(CE->getOperand(0));
874
875    case Instruction::IntToPtr: {
876      // Handle casts to pointers by changing them into casts to the appropriate
877      // integer type.  This promotes constant folding and simplifies this code.
878      Constant *Op = CE->getOperand(0);
879      Op = ConstantExpr::getIntegerCast(Op, TD->getIntPtrType(), false/*ZExt*/);
880      return EmitConstantValueOnly(Op);
881    }
882
883
884    case Instruction::PtrToInt: {
885      // Support only foldable casts to/from pointers that can be eliminated by
886      // changing the pointer to the appropriately sized integer type.
887      Constant *Op = CE->getOperand(0);
888      const Type *Ty = CE->getType();
889
890      // We can emit the pointer value into this slot if the slot is an
891      // integer slot greater or equal to the size of the pointer.
892      if (TD->getTypePaddedSize(Ty) >= TD->getTypePaddedSize(Op->getType()))
893        return EmitConstantValueOnly(Op);
894
895      O << "((";
896      EmitConstantValueOnly(Op);
897      APInt ptrMask = APInt::getAllOnesValue(TD->getTypePaddedSizeInBits(Ty));
898
899      SmallString<40> S;
900      ptrMask.toStringUnsigned(S);
901      O << ") & " << S.c_str() << ')';
902      break;
903    }
904    case Instruction::Add:
905    case Instruction::Sub:
906    case Instruction::And:
907    case Instruction::Or:
908    case Instruction::Xor:
909      O << '(';
910      EmitConstantValueOnly(CE->getOperand(0));
911      O << ')';
912      switch (Opcode) {
913      case Instruction::Add:
914       O << " + ";
915       break;
916      case Instruction::Sub:
917       O << " - ";
918       break;
919      case Instruction::And:
920       O << " & ";
921       break;
922      case Instruction::Or:
923       O << " | ";
924       break;
925      case Instruction::Xor:
926       O << " ^ ";
927       break;
928      default:
929       break;
930      }
931      O << '(';
932      EmitConstantValueOnly(CE->getOperand(1));
933      O << ')';
934      break;
935    default:
936      assert(0 && "Unsupported operator!");
937    }
938  } else {
939    assert(0 && "Unknown constant value!");
940  }
941}
942
943/// printAsCString - Print the specified array as a C compatible string, only if
944/// the predicate isString is true.
945///
946static void printAsCString(raw_ostream &O, const ConstantArray *CVA,
947                           unsigned LastElt) {
948  assert(CVA->isString() && "Array is not string compatible!");
949
950  O << '\"';
951  for (unsigned i = 0; i != LastElt; ++i) {
952    unsigned char C =
953        (unsigned char)cast<ConstantInt>(CVA->getOperand(i))->getZExtValue();
954    printStringChar(O, C);
955  }
956  O << '\"';
957}
958
959/// EmitString - Emit a zero-byte-terminated string constant.
960///
961void AsmPrinter::EmitString(const ConstantArray *CVA) const {
962  unsigned NumElts = CVA->getNumOperands();
963  if (TAI->getAscizDirective() && NumElts &&
964      cast<ConstantInt>(CVA->getOperand(NumElts-1))->getZExtValue() == 0) {
965    O << TAI->getAscizDirective();
966    printAsCString(O, CVA, NumElts-1);
967  } else {
968    O << TAI->getAsciiDirective();
969    printAsCString(O, CVA, NumElts);
970  }
971  O << '\n';
972}
973
974void AsmPrinter::EmitGlobalConstantArray(const ConstantArray *CVA,
975                                         unsigned AddrSpace) {
976  if (CVA->isString()) {
977    EmitString(CVA);
978  } else { // Not a string.  Print the values in successive locations
979    for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i)
980      EmitGlobalConstant(CVA->getOperand(i), AddrSpace);
981  }
982}
983
984void AsmPrinter::EmitGlobalConstantVector(const ConstantVector *CP) {
985  const VectorType *PTy = CP->getType();
986
987  for (unsigned I = 0, E = PTy->getNumElements(); I < E; ++I)
988    EmitGlobalConstant(CP->getOperand(I));
989}
990
991void AsmPrinter::EmitGlobalConstantStruct(const ConstantStruct *CVS,
992                                          unsigned AddrSpace) {
993  // Print the fields in successive locations. Pad to align if needed!
994  const TargetData *TD = TM.getTargetData();
995  unsigned Size = TD->getTypePaddedSize(CVS->getType());
996  const StructLayout *cvsLayout = TD->getStructLayout(CVS->getType());
997  uint64_t sizeSoFar = 0;
998  for (unsigned i = 0, e = CVS->getNumOperands(); i != e; ++i) {
999    const Constant* field = CVS->getOperand(i);
1000
1001    // Check if padding is needed and insert one or more 0s.
1002    uint64_t fieldSize = TD->getTypePaddedSize(field->getType());
1003    uint64_t padSize = ((i == e-1 ? Size : cvsLayout->getElementOffset(i+1))
1004                        - cvsLayout->getElementOffset(i)) - fieldSize;
1005    sizeSoFar += fieldSize + padSize;
1006
1007    // Now print the actual field value.
1008    EmitGlobalConstant(field, AddrSpace);
1009
1010    // Insert padding - this may include padding to increase the size of the
1011    // current field up to the ABI size (if the struct is not packed) as well
1012    // as padding to ensure that the next field starts at the right offset.
1013    EmitZeros(padSize, AddrSpace);
1014  }
1015  assert(sizeSoFar == cvsLayout->getSizeInBytes() &&
1016         "Layout of constant struct may be incorrect!");
1017}
1018
1019void AsmPrinter::EmitGlobalConstantFP(const ConstantFP *CFP,
1020                                      unsigned AddrSpace) {
1021  // FP Constants are printed as integer constants to avoid losing
1022  // precision...
1023  const TargetData *TD = TM.getTargetData();
1024  if (CFP->getType() == Type::DoubleTy) {
1025    double Val = CFP->getValueAPF().convertToDouble();  // for comment only
1026    uint64_t i = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1027    if (TAI->getData64bitsDirective(AddrSpace)) {
1028      O << TAI->getData64bitsDirective(AddrSpace) << i;
1029      if (VerboseAsm)
1030        O << '\t' << TAI->getCommentString() << " double value: " << Val;
1031      O << '\n';
1032    } else if (TD->isBigEndian()) {
1033      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i >> 32);
1034      if (VerboseAsm)
1035        O << '\t' << TAI->getCommentString()
1036          << " double most significant word " << Val;
1037      O << '\n';
1038      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i);
1039      if (VerboseAsm)
1040        O << '\t' << TAI->getCommentString()
1041          << " double least significant word " << Val;
1042      O << '\n';
1043    } else {
1044      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i);
1045      if (VerboseAsm)
1046        O << '\t' << TAI->getCommentString()
1047          << " double least significant word " << Val;
1048      O << '\n';
1049      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i >> 32);
1050      if (VerboseAsm)
1051        O << '\t' << TAI->getCommentString()
1052          << " double most significant word " << Val;
1053      O << '\n';
1054    }
1055    return;
1056  } else if (CFP->getType() == Type::FloatTy) {
1057    float Val = CFP->getValueAPF().convertToFloat();  // for comment only
1058    O << TAI->getData32bitsDirective(AddrSpace)
1059      << CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1060    if (VerboseAsm)
1061      O << '\t' << TAI->getCommentString() << " float " << Val;
1062    O << '\n';
1063    return;
1064  } else if (CFP->getType() == Type::X86_FP80Ty) {
1065    // all long double variants are printed as hex
1066    // api needed to prevent premature destruction
1067    APInt api = CFP->getValueAPF().bitcastToAPInt();
1068    const uint64_t *p = api.getRawData();
1069    // Convert to double so we can print the approximate val as a comment.
1070    APFloat DoubleVal = CFP->getValueAPF();
1071    bool ignored;
1072    DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1073                      &ignored);
1074    if (TD->isBigEndian()) {
1075      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[1]);
1076      if (VerboseAsm)
1077        O << '\t' << TAI->getCommentString()
1078          << " long double most significant halfword of ~"
1079          << DoubleVal.convertToDouble();
1080      O << '\n';
1081      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 48);
1082      if (VerboseAsm)
1083        O << '\t' << TAI->getCommentString() << " long double next halfword";
1084      O << '\n';
1085      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 32);
1086      if (VerboseAsm)
1087        O << '\t' << TAI->getCommentString() << " long double next halfword";
1088      O << '\n';
1089      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 16);
1090      if (VerboseAsm)
1091        O << '\t' << TAI->getCommentString() << " long double next halfword";
1092      O << '\n';
1093      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0]);
1094      if (VerboseAsm)
1095        O << '\t' << TAI->getCommentString()
1096          << " long double least significant halfword";
1097      O << '\n';
1098     } else {
1099      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0]);
1100      if (VerboseAsm)
1101        O << '\t' << TAI->getCommentString()
1102          << " long double least significant halfword of ~"
1103          << DoubleVal.convertToDouble();
1104      O << '\n';
1105      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 16);
1106      if (VerboseAsm)
1107        O << '\t' << TAI->getCommentString()
1108          << " long double next halfword";
1109      O << '\n';
1110      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 32);
1111      if (VerboseAsm)
1112        O << '\t' << TAI->getCommentString()
1113          << " long double next halfword";
1114      O << '\n';
1115      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 48);
1116      if (VerboseAsm)
1117        O << '\t' << TAI->getCommentString()
1118          << " long double next halfword";
1119      O << '\n';
1120      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[1]);
1121      if (VerboseAsm)
1122        O << '\t' << TAI->getCommentString()
1123          << " long double most significant halfword";
1124      O << '\n';
1125    }
1126    EmitZeros(TD->getTypePaddedSize(Type::X86_FP80Ty) -
1127              TD->getTypeStoreSize(Type::X86_FP80Ty), AddrSpace);
1128    return;
1129  } else if (CFP->getType() == Type::PPC_FP128Ty) {
1130    // all long double variants are printed as hex
1131    // api needed to prevent premature destruction
1132    APInt api = CFP->getValueAPF().bitcastToAPInt();
1133    const uint64_t *p = api.getRawData();
1134    if (TD->isBigEndian()) {
1135      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0] >> 32);
1136      if (VerboseAsm)
1137        O << '\t' << TAI->getCommentString()
1138          << " long double most significant word";
1139      O << '\n';
1140      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0]);
1141      if (VerboseAsm)
1142        O << '\t' << TAI->getCommentString()
1143        << " long double next word";
1144      O << '\n';
1145      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1] >> 32);
1146      if (VerboseAsm)
1147        O << '\t' << TAI->getCommentString()
1148          << " long double next word";
1149      O << '\n';
1150      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1]);
1151      if (VerboseAsm)
1152        O << '\t' << TAI->getCommentString()
1153          << " long double least significant word";
1154      O << '\n';
1155     } else {
1156      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1]);
1157      if (VerboseAsm)
1158        O << '\t' << TAI->getCommentString()
1159          << " long double least significant word";
1160      O << '\n';
1161      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1] >> 32);
1162      if (VerboseAsm)
1163        O << '\t' << TAI->getCommentString()
1164          << " long double next word";
1165      O << '\n';
1166      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0]);
1167      if (VerboseAsm)
1168        O << '\t' << TAI->getCommentString()
1169          << " long double next word";
1170      O << '\n';
1171      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0] >> 32);
1172      if (VerboseAsm)
1173        O << '\t' << TAI->getCommentString()
1174          << " long double most significant word";
1175      O << '\n';
1176    }
1177    return;
1178  } else assert(0 && "Floating point constant type not handled");
1179}
1180
1181void AsmPrinter::EmitGlobalConstantLargeInt(const ConstantInt *CI,
1182                                            unsigned AddrSpace) {
1183  const TargetData *TD = TM.getTargetData();
1184  unsigned BitWidth = CI->getBitWidth();
1185  assert(isPowerOf2_32(BitWidth) &&
1186         "Non-power-of-2-sized integers not handled!");
1187
1188  // We don't expect assemblers to support integer data directives
1189  // for more than 64 bits, so we emit the data in at most 64-bit
1190  // quantities at a time.
1191  const uint64_t *RawData = CI->getValue().getRawData();
1192  for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1193    uint64_t Val;
1194    if (TD->isBigEndian())
1195      Val = RawData[e - i - 1];
1196    else
1197      Val = RawData[i];
1198
1199    if (TAI->getData64bitsDirective(AddrSpace))
1200      O << TAI->getData64bitsDirective(AddrSpace) << Val << '\n';
1201    else if (TD->isBigEndian()) {
1202      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val >> 32);
1203      if (VerboseAsm)
1204        O << '\t' << TAI->getCommentString()
1205          << " Double-word most significant word " << Val;
1206      O << '\n';
1207      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val);
1208      if (VerboseAsm)
1209        O << '\t' << TAI->getCommentString()
1210          << " Double-word least significant word " << Val;
1211      O << '\n';
1212    } else {
1213      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val);
1214      if (VerboseAsm)
1215        O << '\t' << TAI->getCommentString()
1216          << " Double-word least significant word " << Val;
1217      O << '\n';
1218      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val >> 32);
1219      if (VerboseAsm)
1220        O << '\t' << TAI->getCommentString()
1221          << " Double-word most significant word " << Val;
1222      O << '\n';
1223    }
1224  }
1225}
1226
1227/// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1228void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1229  const TargetData *TD = TM.getTargetData();
1230  const Type *type = CV->getType();
1231  unsigned Size = TD->getTypePaddedSize(type);
1232
1233  if (CV->isNullValue() || isa<UndefValue>(CV)) {
1234    EmitZeros(Size, AddrSpace);
1235    return;
1236  } else if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) {
1237    EmitGlobalConstantArray(CVA , AddrSpace);
1238    return;
1239  } else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) {
1240    EmitGlobalConstantStruct(CVS, AddrSpace);
1241    return;
1242  } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) {
1243    EmitGlobalConstantFP(CFP, AddrSpace);
1244    return;
1245  } else if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1246    // Small integers are handled below; large integers are handled here.
1247    if (Size > 4) {
1248      EmitGlobalConstantLargeInt(CI, AddrSpace);
1249      return;
1250    }
1251  } else if (const ConstantVector *CP = dyn_cast<ConstantVector>(CV)) {
1252    EmitGlobalConstantVector(CP);
1253    return;
1254  }
1255
1256  printDataDirective(type, AddrSpace);
1257  EmitConstantValueOnly(CV);
1258  if (VerboseAsm) {
1259    if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1260      SmallString<40> S;
1261      CI->getValue().toStringUnsigned(S, 16);
1262      O << "\t\t\t" << TAI->getCommentString() << " 0x" << S.c_str();
1263    }
1264  }
1265  O << '\n';
1266}
1267
1268void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1269  // Target doesn't support this yet!
1270  abort();
1271}
1272
1273/// PrintSpecial - Print information related to the specified machine instr
1274/// that is independent of the operand, and may be independent of the instr
1275/// itself.  This can be useful for portably encoding the comment character
1276/// or other bits of target-specific knowledge into the asmstrings.  The
1277/// syntax used is ${:comment}.  Targets can override this to add support
1278/// for their own strange codes.
1279void AsmPrinter::PrintSpecial(const MachineInstr *MI, const char *Code) const {
1280  if (!strcmp(Code, "private")) {
1281    O << TAI->getPrivateGlobalPrefix();
1282  } else if (!strcmp(Code, "comment")) {
1283    if (VerboseAsm)
1284      O << TAI->getCommentString();
1285  } else if (!strcmp(Code, "uid")) {
1286    // Assign a unique ID to this machine instruction.
1287    static const MachineInstr *LastMI = 0;
1288    static const Function *F = 0;
1289    static unsigned Counter = 0U-1;
1290
1291    // Comparing the address of MI isn't sufficient, because machineinstrs may
1292    // be allocated to the same address across functions.
1293    const Function *ThisF = MI->getParent()->getParent()->getFunction();
1294
1295    // If this is a new machine instruction, bump the counter.
1296    if (LastMI != MI || F != ThisF) {
1297      ++Counter;
1298      LastMI = MI;
1299      F = ThisF;
1300    }
1301    O << Counter;
1302  } else {
1303    cerr << "Unknown special formatter '" << Code
1304         << "' for machine instr: " << *MI;
1305    exit(1);
1306  }
1307}
1308
1309/// processDebugLoc - Processes the debug information of each machine
1310/// instruction's DebugLoc.
1311void AsmPrinter::processDebugLoc(DebugLoc DL) {
1312  if (TAI->doesSupportDebugInformation() && DW->ShouldEmitDwarfDebug()) {
1313    if (!DL.isUnknown()) {
1314      static DebugLocTuple PrevDLT(0, ~0U, ~0U);
1315      DebugLocTuple CurDLT = MF->getDebugLocTuple(DL);
1316
1317      if (CurDLT.CompileUnit != 0 && PrevDLT != CurDLT)
1318        printLabel(DW->RecordSourceLine(CurDLT.Line, CurDLT.Col,
1319                                        DICompileUnit(CurDLT.CompileUnit)));
1320
1321      PrevDLT = CurDLT;
1322    }
1323  }
1324}
1325
1326/// printInlineAsm - This method formats and prints the specified machine
1327/// instruction that is an inline asm.
1328void AsmPrinter::printInlineAsm(const MachineInstr *MI) const {
1329  unsigned NumOperands = MI->getNumOperands();
1330
1331  // Count the number of register definitions.
1332  unsigned NumDefs = 0;
1333  for (; MI->getOperand(NumDefs).isReg() && MI->getOperand(NumDefs).isDef();
1334       ++NumDefs)
1335    assert(NumDefs != NumOperands-1 && "No asm string?");
1336
1337  assert(MI->getOperand(NumDefs).isSymbol() && "No asm string?");
1338
1339  // Disassemble the AsmStr, printing out the literal pieces, the operands, etc.
1340  const char *AsmStr = MI->getOperand(NumDefs).getSymbolName();
1341
1342  // If this asmstr is empty, just print the #APP/#NOAPP markers.
1343  // These are useful to see where empty asm's wound up.
1344  if (AsmStr[0] == 0) {
1345    O << TAI->getInlineAsmStart() << "\n\t" << TAI->getInlineAsmEnd() << '\n';
1346    return;
1347  }
1348
1349  O << TAI->getInlineAsmStart() << "\n\t";
1350
1351  // The variant of the current asmprinter.
1352  int AsmPrinterVariant = TAI->getAssemblerDialect();
1353
1354  int CurVariant = -1;            // The number of the {.|.|.} region we are in.
1355  const char *LastEmitted = AsmStr; // One past the last character emitted.
1356
1357  while (*LastEmitted) {
1358    switch (*LastEmitted) {
1359    default: {
1360      // Not a special case, emit the string section literally.
1361      const char *LiteralEnd = LastEmitted+1;
1362      while (*LiteralEnd && *LiteralEnd != '{' && *LiteralEnd != '|' &&
1363             *LiteralEnd != '}' && *LiteralEnd != '$' && *LiteralEnd != '\n')
1364        ++LiteralEnd;
1365      if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1366        O.write(LastEmitted, LiteralEnd-LastEmitted);
1367      LastEmitted = LiteralEnd;
1368      break;
1369    }
1370    case '\n':
1371      ++LastEmitted;   // Consume newline character.
1372      O << '\n';       // Indent code with newline.
1373      break;
1374    case '$': {
1375      ++LastEmitted;   // Consume '$' character.
1376      bool Done = true;
1377
1378      // Handle escapes.
1379      switch (*LastEmitted) {
1380      default: Done = false; break;
1381      case '$':     // $$ -> $
1382        if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1383          O << '$';
1384        ++LastEmitted;  // Consume second '$' character.
1385        break;
1386      case '(':             // $( -> same as GCC's { character.
1387        ++LastEmitted;      // Consume '(' character.
1388        if (CurVariant != -1) {
1389          cerr << "Nested variants found in inline asm string: '"
1390               << AsmStr << "'\n";
1391          exit(1);
1392        }
1393        CurVariant = 0;     // We're in the first variant now.
1394        break;
1395      case '|':
1396        ++LastEmitted;  // consume '|' character.
1397        if (CurVariant == -1)
1398          O << '|';       // this is gcc's behavior for | outside a variant
1399        else
1400          ++CurVariant;   // We're in the next variant.
1401        break;
1402      case ')':         // $) -> same as GCC's } char.
1403        ++LastEmitted;  // consume ')' character.
1404        if (CurVariant == -1)
1405          O << '}';     // this is gcc's behavior for } outside a variant
1406        else
1407          CurVariant = -1;
1408        break;
1409      }
1410      if (Done) break;
1411
1412      bool HasCurlyBraces = false;
1413      if (*LastEmitted == '{') {     // ${variable}
1414        ++LastEmitted;               // Consume '{' character.
1415        HasCurlyBraces = true;
1416      }
1417
1418      // If we have ${:foo}, then this is not a real operand reference, it is a
1419      // "magic" string reference, just like in .td files.  Arrange to call
1420      // PrintSpecial.
1421      if (HasCurlyBraces && *LastEmitted == ':') {
1422        ++LastEmitted;
1423        const char *StrStart = LastEmitted;
1424        const char *StrEnd = strchr(StrStart, '}');
1425        if (StrEnd == 0) {
1426          cerr << "Unterminated ${:foo} operand in inline asm string: '"
1427               << AsmStr << "'\n";
1428          exit(1);
1429        }
1430
1431        std::string Val(StrStart, StrEnd);
1432        PrintSpecial(MI, Val.c_str());
1433        LastEmitted = StrEnd+1;
1434        break;
1435      }
1436
1437      const char *IDStart = LastEmitted;
1438      char *IDEnd;
1439      errno = 0;
1440      long Val = strtol(IDStart, &IDEnd, 10); // We only accept numbers for IDs.
1441      if (!isdigit(*IDStart) || (Val == 0 && errno == EINVAL)) {
1442        cerr << "Bad $ operand number in inline asm string: '"
1443             << AsmStr << "'\n";
1444        exit(1);
1445      }
1446      LastEmitted = IDEnd;
1447
1448      char Modifier[2] = { 0, 0 };
1449
1450      if (HasCurlyBraces) {
1451        // If we have curly braces, check for a modifier character.  This
1452        // supports syntax like ${0:u}, which correspond to "%u0" in GCC asm.
1453        if (*LastEmitted == ':') {
1454          ++LastEmitted;    // Consume ':' character.
1455          if (*LastEmitted == 0) {
1456            cerr << "Bad ${:} expression in inline asm string: '"
1457                 << AsmStr << "'\n";
1458            exit(1);
1459          }
1460
1461          Modifier[0] = *LastEmitted;
1462          ++LastEmitted;    // Consume modifier character.
1463        }
1464
1465        if (*LastEmitted != '}') {
1466          cerr << "Bad ${} expression in inline asm string: '"
1467               << AsmStr << "'\n";
1468          exit(1);
1469        }
1470        ++LastEmitted;    // Consume '}' character.
1471      }
1472
1473      if ((unsigned)Val >= NumOperands-1) {
1474        cerr << "Invalid $ operand number in inline asm string: '"
1475             << AsmStr << "'\n";
1476        exit(1);
1477      }
1478
1479      // Okay, we finally have a value number.  Ask the target to print this
1480      // operand!
1481      if (CurVariant == -1 || CurVariant == AsmPrinterVariant) {
1482        unsigned OpNo = 1;
1483
1484        bool Error = false;
1485
1486        // Scan to find the machine operand number for the operand.
1487        for (; Val; --Val) {
1488          if (OpNo >= MI->getNumOperands()) break;
1489          unsigned OpFlags = MI->getOperand(OpNo).getImm();
1490          OpNo += InlineAsm::getNumOperandRegisters(OpFlags) + 1;
1491        }
1492
1493        if (OpNo >= MI->getNumOperands()) {
1494          Error = true;
1495        } else {
1496          unsigned OpFlags = MI->getOperand(OpNo).getImm();
1497          ++OpNo;  // Skip over the ID number.
1498
1499          if (Modifier[0]=='l')  // labels are target independent
1500            printBasicBlockLabel(MI->getOperand(OpNo).getMBB(),
1501                                 false, false, false);
1502          else {
1503            AsmPrinter *AP = const_cast<AsmPrinter*>(this);
1504            if ((OpFlags & 7) == 4) {
1505              Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant,
1506                                                Modifier[0] ? Modifier : 0);
1507            } else {
1508              Error = AP->PrintAsmOperand(MI, OpNo, AsmPrinterVariant,
1509                                          Modifier[0] ? Modifier : 0);
1510            }
1511          }
1512        }
1513        if (Error) {
1514          cerr << "Invalid operand found in inline asm: '"
1515               << AsmStr << "'\n";
1516          MI->dump();
1517          exit(1);
1518        }
1519      }
1520      break;
1521    }
1522    }
1523  }
1524  O << "\n\t" << TAI->getInlineAsmEnd() << '\n';
1525}
1526
1527/// printImplicitDef - This method prints the specified machine instruction
1528/// that is an implicit def.
1529void AsmPrinter::printImplicitDef(const MachineInstr *MI) const {
1530  if (VerboseAsm)
1531    O << '\t' << TAI->getCommentString() << " implicit-def: "
1532      << TRI->getAsmName(MI->getOperand(0).getReg()) << '\n';
1533}
1534
1535/// printLabel - This method prints a local label used by debug and
1536/// exception handling tables.
1537void AsmPrinter::printLabel(const MachineInstr *MI) const {
1538  printLabel(MI->getOperand(0).getImm());
1539}
1540
1541void AsmPrinter::printLabel(unsigned Id) const {
1542  O << TAI->getPrivateGlobalPrefix() << "label" << Id << ":\n";
1543}
1544
1545/// printDeclare - This method prints a local variable declaration used by
1546/// debug tables.
1547/// FIXME: It doesn't really print anything rather it inserts a DebugVariable
1548/// entry into dwarf table.
1549void AsmPrinter::printDeclare(const MachineInstr *MI) const {
1550  unsigned FI = MI->getOperand(0).getIndex();
1551  GlobalValue *GV = MI->getOperand(1).getGlobal();
1552  DW->RecordVariable(cast<GlobalVariable>(GV), FI, MI);
1553}
1554
1555/// PrintAsmOperand - Print the specified operand of MI, an INLINEASM
1556/// instruction, using the specified assembler variant.  Targets should
1557/// overried this to format as appropriate.
1558bool AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
1559                                 unsigned AsmVariant, const char *ExtraCode) {
1560  // Target doesn't support this yet!
1561  return true;
1562}
1563
1564bool AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
1565                                       unsigned AsmVariant,
1566                                       const char *ExtraCode) {
1567  // Target doesn't support this yet!
1568  return true;
1569}
1570
1571/// printBasicBlockLabel - This method prints the label for the specified
1572/// MachineBasicBlock
1573void AsmPrinter::printBasicBlockLabel(const MachineBasicBlock *MBB,
1574                                      bool printAlign,
1575                                      bool printColon,
1576                                      bool printComment) const {
1577  if (printAlign) {
1578    unsigned Align = MBB->getAlignment();
1579    if (Align)
1580      EmitAlignment(Log2_32(Align));
1581  }
1582
1583  O << TAI->getPrivateGlobalPrefix() << "BB" << getFunctionNumber() << '_'
1584    << MBB->getNumber();
1585  if (printColon)
1586    O << ':';
1587  if (printComment && MBB->getBasicBlock())
1588    O << '\t' << TAI->getCommentString() << ' '
1589      << MBB->getBasicBlock()->getNameStart();
1590}
1591
1592/// printPICJumpTableSetLabel - This method prints a set label for the
1593/// specified MachineBasicBlock for a jumptable entry.
1594void AsmPrinter::printPICJumpTableSetLabel(unsigned uid,
1595                                           const MachineBasicBlock *MBB) const {
1596  if (!TAI->getSetDirective())
1597    return;
1598
1599  O << TAI->getSetDirective() << ' ' << TAI->getPrivateGlobalPrefix()
1600    << getFunctionNumber() << '_' << uid << "_set_" << MBB->getNumber() << ',';
1601  printBasicBlockLabel(MBB, false, false, false);
1602  O << '-' << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
1603    << '_' << uid << '\n';
1604}
1605
1606void AsmPrinter::printPICJumpTableSetLabel(unsigned uid, unsigned uid2,
1607                                           const MachineBasicBlock *MBB) const {
1608  if (!TAI->getSetDirective())
1609    return;
1610
1611  O << TAI->getSetDirective() << ' ' << TAI->getPrivateGlobalPrefix()
1612    << getFunctionNumber() << '_' << uid << '_' << uid2
1613    << "_set_" << MBB->getNumber() << ',';
1614  printBasicBlockLabel(MBB, false, false, false);
1615  O << '-' << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
1616    << '_' << uid << '_' << uid2 << '\n';
1617}
1618
1619/// printDataDirective - This method prints the asm directive for the
1620/// specified type.
1621void AsmPrinter::printDataDirective(const Type *type, unsigned AddrSpace) {
1622  const TargetData *TD = TM.getTargetData();
1623  switch (type->getTypeID()) {
1624  case Type::IntegerTyID: {
1625    unsigned BitWidth = cast<IntegerType>(type)->getBitWidth();
1626    if (BitWidth <= 8)
1627      O << TAI->getData8bitsDirective(AddrSpace);
1628    else if (BitWidth <= 16)
1629      O << TAI->getData16bitsDirective(AddrSpace);
1630    else if (BitWidth <= 32)
1631      O << TAI->getData32bitsDirective(AddrSpace);
1632    else if (BitWidth <= 64) {
1633      assert(TAI->getData64bitsDirective(AddrSpace) &&
1634             "Target cannot handle 64-bit constant exprs!");
1635      O << TAI->getData64bitsDirective(AddrSpace);
1636    } else {
1637      assert(0 && "Target cannot handle given data directive width!");
1638    }
1639    break;
1640  }
1641  case Type::PointerTyID:
1642    if (TD->getPointerSize() == 8) {
1643      assert(TAI->getData64bitsDirective(AddrSpace) &&
1644             "Target cannot handle 64-bit pointer exprs!");
1645      O << TAI->getData64bitsDirective(AddrSpace);
1646    } else if (TD->getPointerSize() == 2) {
1647      O << TAI->getData16bitsDirective(AddrSpace);
1648    } else if (TD->getPointerSize() == 1) {
1649      O << TAI->getData8bitsDirective(AddrSpace);
1650    } else {
1651      O << TAI->getData32bitsDirective(AddrSpace);
1652    }
1653    break;
1654  case Type::FloatTyID: case Type::DoubleTyID:
1655  case Type::X86_FP80TyID: case Type::FP128TyID: case Type::PPC_FP128TyID:
1656    assert (0 && "Should have already output floating point constant.");
1657  default:
1658    assert (0 && "Can't handle printing this type of thing");
1659    break;
1660  }
1661}
1662
1663void AsmPrinter::printSuffixedName(const char *Name, const char *Suffix,
1664                                   const char *Prefix) {
1665  if (Name[0]=='\"')
1666    O << '\"';
1667  O << TAI->getPrivateGlobalPrefix();
1668  if (Prefix) O << Prefix;
1669  if (Name[0]=='\"')
1670    O << '\"';
1671  if (Name[0]=='\"')
1672    O << Name[1];
1673  else
1674    O << Name;
1675  O << Suffix;
1676  if (Name[0]=='\"')
1677    O << '\"';
1678}
1679
1680void AsmPrinter::printSuffixedName(const std::string &Name, const char* Suffix) {
1681  printSuffixedName(Name.c_str(), Suffix);
1682}
1683
1684void AsmPrinter::printVisibility(const std::string& Name,
1685                                 unsigned Visibility) const {
1686  if (Visibility == GlobalValue::HiddenVisibility) {
1687    if (const char *Directive = TAI->getHiddenDirective())
1688      O << Directive << Name << '\n';
1689  } else if (Visibility == GlobalValue::ProtectedVisibility) {
1690    if (const char *Directive = TAI->getProtectedDirective())
1691      O << Directive << Name << '\n';
1692  }
1693}
1694
1695void AsmPrinter::printOffset(int64_t Offset) const {
1696  if (Offset > 0)
1697    O << '+' << Offset;
1698  else if (Offset < 0)
1699    O << Offset;
1700}
1701
1702GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1703  if (!S->usesMetadata())
1704    return 0;
1705
1706  gcp_iterator GCPI = GCMetadataPrinters.find(S);
1707  if (GCPI != GCMetadataPrinters.end())
1708    return GCPI->second;
1709
1710  const char *Name = S->getName().c_str();
1711
1712  for (GCMetadataPrinterRegistry::iterator
1713         I = GCMetadataPrinterRegistry::begin(),
1714         E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1715    if (strcmp(Name, I->getName()) == 0) {
1716      GCMetadataPrinter *GMP = I->instantiate();
1717      GMP->S = S;
1718      GCMetadataPrinters.insert(std::make_pair(S, GMP));
1719      return GMP;
1720    }
1721
1722  cerr << "no GCMetadataPrinter registered for GC: " << Name << "\n";
1723  abort();
1724}
1725