AsmPrinter.cpp revision 16fe990e56102a355f1e77aca93bf8c79d7b9eb2 
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/MC/MCInst.h"
26#include "llvm/Support/CommandLine.h"
27#include "llvm/Support/ErrorHandling.h"
28#include "llvm/Support/FormattedStream.h"
29#include "llvm/Support/Mangler.h"
30#include "llvm/Support/FormattedStream.h"
31#include "llvm/Target/TargetAsmInfo.h"
32#include "llvm/Target/TargetData.h"
33#include "llvm/Target/TargetLowering.h"
34#include "llvm/Target/TargetOptions.h"
35#include "llvm/Target/TargetRegisterInfo.h"
36#include "llvm/ADT/SmallPtrSet.h"
37#include "llvm/ADT/SmallString.h"
38#include "llvm/ADT/StringExtras.h"
39#include <cerrno>
40using namespace llvm;
41
42static cl::opt<cl::boolOrDefault>
43AsmVerbose("asm-verbose", cl::desc("Add comments to directives."),
44           cl::init(cl::BOU_UNSET));
45
46char AsmPrinter::ID = 0;
47AsmPrinter::AsmPrinter(formatted_raw_ostream &o, TargetMachine &tm,
48                       const TargetAsmInfo *T, bool VDef)
49  : MachineFunctionPass(&ID), FunctionNumber(0), O(o),
50    TM(tm), TAI(T), TRI(tm.getRegisterInfo()),
51    IsInTextSection(false), LastMI(0), LastFn(0), Counter(~0U),
52    PrevDLT(0, ~0U, ~0U) {
53  DW = 0; MMI = 0;
54  switch (AsmVerbose) {
55  case cl::BOU_UNSET: VerboseAsm = VDef;  break;
56  case cl::BOU_TRUE:  VerboseAsm = true;  break;
57  case cl::BOU_FALSE: VerboseAsm = false; break;
58  }
59}
60
61AsmPrinter::~AsmPrinter() {
62  for (gcp_iterator I = GCMetadataPrinters.begin(),
63                    E = GCMetadataPrinters.end(); I != E; ++I)
64    delete I->second;
65}
66
67/// SwitchToTextSection - Switch to the specified text section of the executable
68/// if we are not already in it!
69///
70void AsmPrinter::SwitchToTextSection(const char *NewSection,
71                                     const GlobalValue *GV) {
72  std::string NS;
73  if (GV && GV->hasSection())
74    NS = TAI->getSwitchToSectionDirective() + GV->getSection();
75  else
76    NS = NewSection;
77
78  // If we're already in this section, we're done.
79  if (CurrentSection == NS) return;
80
81  // Close the current section, if applicable.
82  if (TAI->getSectionEndDirectiveSuffix() && !CurrentSection.empty())
83    O << CurrentSection << TAI->getSectionEndDirectiveSuffix() << '\n';
84
85  CurrentSection = NS;
86
87  if (!CurrentSection.empty())
88    O << CurrentSection << TAI->getTextSectionStartSuffix() << '\n';
89
90  IsInTextSection = true;
91}
92
93/// SwitchToDataSection - Switch to the specified data section of the executable
94/// if we are not already in it!
95///
96void AsmPrinter::SwitchToDataSection(const char *NewSection,
97                                     const GlobalValue *GV) {
98  std::string NS;
99  if (GV && GV->hasSection())
100    NS = TAI->getSwitchToSectionDirective() + GV->getSection();
101  else
102    NS = NewSection;
103
104  // If we're already in this section, we're done.
105  if (CurrentSection == NS) return;
106
107  // Close the current section, if applicable.
108  if (TAI->getSectionEndDirectiveSuffix() && !CurrentSection.empty())
109    O << CurrentSection << TAI->getSectionEndDirectiveSuffix() << '\n';
110
111  CurrentSection = NS;
112
113  if (!CurrentSection.empty())
114    O << CurrentSection << TAI->getDataSectionStartSuffix() << '\n';
115
116  IsInTextSection = false;
117}
118
119/// SwitchToSection - Switch to the specified section of the executable if we
120/// are not already in it!
121void AsmPrinter::SwitchToSection(const Section* NS) {
122  const std::string& NewSection = NS->getName();
123
124  // If we're already in this section, we're done.
125  if (CurrentSection == NewSection) return;
126
127  // Close the current section, if applicable.
128  if (TAI->getSectionEndDirectiveSuffix() && !CurrentSection.empty())
129    O << CurrentSection << TAI->getSectionEndDirectiveSuffix() << '\n';
130
131  // FIXME: Make CurrentSection a Section* in the future
132  CurrentSection = NewSection;
133  CurrentSection_ = NS;
134
135  if (!CurrentSection.empty()) {
136    // If section is named we need to switch into it via special '.section'
137    // directive and also append funky flags. Otherwise - section name is just
138    // some magic assembler directive.
139    if (NS->isNamed())
140      O << TAI->getSwitchToSectionDirective()
141        << CurrentSection
142        << TAI->getSectionFlags(NS->getFlags());
143    else
144      O << CurrentSection;
145    O << TAI->getDataSectionStartSuffix() << '\n';
146  }
147
148  IsInTextSection = (NS->getFlags() & SectionFlags::Code);
149}
150
151void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
152  MachineFunctionPass::getAnalysisUsage(AU);
153  AU.addRequired<GCModuleInfo>();
154}
155
156bool AsmPrinter::doInitialization(Module &M) {
157  Mang = new Mangler(M, TAI->getGlobalPrefix(), TAI->getPrivateGlobalPrefix());
158
159  if (TAI->doesAllowQuotesInName())
160    Mang->setUseQuotes(true);
161
162  GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
163  assert(MI && "AsmPrinter didn't require GCModuleInfo?");
164
165  if (TAI->hasSingleParameterDotFile()) {
166    /* Very minimal debug info. It is ignored if we emit actual
167       debug info. If we don't, this at helps the user find where
168       a function came from. */
169    O << "\t.file\t\"" << M.getModuleIdentifier() << "\"\n";
170  }
171
172  for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
173    if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
174      MP->beginAssembly(O, *this, *TAI);
175
176  if (!M.getModuleInlineAsm().empty())
177    O << TAI->getCommentString() << " Start of file scope inline assembly\n"
178      << M.getModuleInlineAsm()
179      << '\n' << TAI->getCommentString()
180      << " End of file scope inline assembly\n";
181
182  SwitchToDataSection("");   // Reset back to no section.
183
184  if (TAI->doesSupportDebugInformation() ||
185      TAI->doesSupportExceptionHandling()) {
186    MMI = getAnalysisIfAvailable<MachineModuleInfo>();
187    if (MMI)
188      MMI->AnalyzeModule(M);
189    DW = getAnalysisIfAvailable<DwarfWriter>();
190    if (DW)
191      DW->BeginModule(&M, MMI, O, this, TAI);
192  }
193
194  return false;
195}
196
197bool AsmPrinter::doFinalization(Module &M) {
198  // Emit final debug information.
199  if (TAI->doesSupportDebugInformation() || TAI->doesSupportExceptionHandling())
200    DW->EndModule();
201
202  // If the target wants to know about weak references, print them all.
203  if (TAI->getWeakRefDirective()) {
204    // FIXME: This is not lazy, it would be nice to only print weak references
205    // to stuff that is actually used.  Note that doing so would require targets
206    // to notice uses in operands (due to constant exprs etc).  This should
207    // happen with the MC stuff eventually.
208    SwitchToDataSection("");
209
210    // Print out module-level global variables here.
211    for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
212         I != E; ++I) {
213      if (I->hasExternalWeakLinkage())
214        O << TAI->getWeakRefDirective() << Mang->getMangledName(I) << '\n';
215    }
216
217    for (Module::const_iterator I = M.begin(), E = M.end();
218         I != E; ++I) {
219      if (I->hasExternalWeakLinkage())
220        O << TAI->getWeakRefDirective() << Mang->getMangledName(I) << '\n';
221    }
222  }
223
224  if (TAI->getSetDirective()) {
225    if (!M.alias_empty())
226      SwitchToSection(TAI->getTextSection());
227
228    O << '\n';
229    for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
230         I != E; ++I) {
231      std::string Name = Mang->getMangledName(I);
232
233      const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
234      std::string Target = Mang->getMangledName(GV);
235
236      if (I->hasExternalLinkage() || !TAI->getWeakRefDirective())
237        O << "\t.globl\t" << Name << '\n';
238      else if (I->hasWeakLinkage())
239        O << TAI->getWeakRefDirective() << Name << '\n';
240      else if (!I->hasLocalLinkage())
241        llvm_unreachable("Invalid alias linkage");
242
243      printVisibility(Name, I->getVisibility());
244
245      O << TAI->getSetDirective() << ' ' << Name << ", " << Target << '\n';
246    }
247  }
248
249  GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
250  assert(MI && "AsmPrinter didn't require GCModuleInfo?");
251  for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
252    if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
253      MP->finishAssembly(O, *this, *TAI);
254
255  // If we don't have any trampolines, then we don't require stack memory
256  // to be executable. Some targets have a directive to declare this.
257  Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
258  if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
259    if (TAI->getNonexecutableStackDirective())
260      O << TAI->getNonexecutableStackDirective() << '\n';
261
262  delete Mang; Mang = 0;
263  DW = 0; MMI = 0;
264  return false;
265}
266
267std::string
268AsmPrinter::getCurrentFunctionEHName(const MachineFunction *MF) const {
269  assert(MF && "No machine function?");
270  return Mang->getMangledName(MF->getFunction(), ".eh",
271                              TAI->is_EHSymbolPrivate());
272}
273
274void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
275  // What's my mangled name?
276  CurrentFnName = Mang->getMangledName(MF.getFunction());
277  IncrementFunctionNumber();
278}
279
280namespace {
281  // SectionCPs - Keep track the alignment, constpool entries per Section.
282  struct SectionCPs {
283    const Section *S;
284    unsigned Alignment;
285    SmallVector<unsigned, 4> CPEs;
286    SectionCPs(const Section *s, unsigned a) : S(s), Alignment(a) {};
287  };
288}
289
290/// EmitConstantPool - Print to the current output stream assembly
291/// representations of the constants in the constant pool MCP. This is
292/// used to print out constants which have been "spilled to memory" by
293/// the code generator.
294///
295void AsmPrinter::EmitConstantPool(MachineConstantPool *MCP) {
296  const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
297  if (CP.empty()) return;
298
299  // Calculate sections for constant pool entries. We collect entries to go into
300  // the same section together to reduce amount of section switch statements.
301  SmallVector<SectionCPs, 4> CPSections;
302  for (unsigned i = 0, e = CP.size(); i != e; ++i) {
303    MachineConstantPoolEntry CPE = CP[i];
304    unsigned Align = CPE.getAlignment();
305    const Section* S = TAI->SelectSectionForMachineConst(CPE.getType());
306    // The number of sections are small, just do a linear search from the
307    // last section to the first.
308    bool Found = false;
309    unsigned SecIdx = CPSections.size();
310    while (SecIdx != 0) {
311      if (CPSections[--SecIdx].S == S) {
312        Found = true;
313        break;
314      }
315    }
316    if (!Found) {
317      SecIdx = CPSections.size();
318      CPSections.push_back(SectionCPs(S, Align));
319    }
320
321    if (Align > CPSections[SecIdx].Alignment)
322      CPSections[SecIdx].Alignment = Align;
323    CPSections[SecIdx].CPEs.push_back(i);
324  }
325
326  // Now print stuff into the calculated sections.
327  for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
328    SwitchToSection(CPSections[i].S);
329    EmitAlignment(Log2_32(CPSections[i].Alignment));
330
331    unsigned Offset = 0;
332    for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
333      unsigned CPI = CPSections[i].CPEs[j];
334      MachineConstantPoolEntry CPE = CP[CPI];
335
336      // Emit inter-object padding for alignment.
337      unsigned AlignMask = CPE.getAlignment() - 1;
338      unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
339      EmitZeros(NewOffset - Offset);
340
341      const Type *Ty = CPE.getType();
342      Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
343
344      O << TAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << '_'
345        << CPI << ":\t\t\t\t\t";
346      if (VerboseAsm) {
347        O << TAI->getCommentString() << ' ';
348        WriteTypeSymbolic(O, CPE.getType(), 0);
349      }
350      O << '\n';
351      if (CPE.isMachineConstantPoolEntry())
352        EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
353      else
354        EmitGlobalConstant(CPE.Val.ConstVal);
355    }
356  }
357}
358
359/// EmitJumpTableInfo - Print assembly representations of the jump tables used
360/// by the current function to the current output stream.
361///
362void AsmPrinter::EmitJumpTableInfo(MachineJumpTableInfo *MJTI,
363                                   MachineFunction &MF) {
364  const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
365  if (JT.empty()) return;
366
367  bool IsPic = TM.getRelocationModel() == Reloc::PIC_;
368
369  // Pick the directive to use to print the jump table entries, and switch to
370  // the appropriate section.
371  TargetLowering *LoweringInfo = TM.getTargetLowering();
372
373  const char* JumpTableDataSection = TAI->getJumpTableDataSection();
374  const Function *F = MF.getFunction();
375  unsigned SectionFlags = TAI->SectionFlagsForGlobal(F);
376  bool JTInDiffSection = false;
377  if ((IsPic && !(LoweringInfo && LoweringInfo->usesGlobalOffsetTable())) ||
378      !JumpTableDataSection ||
379      SectionFlags & SectionFlags::Linkonce) {
380    // In PIC mode, we need to emit the jump table to the same section as the
381    // function body itself, otherwise the label differences won't make sense.
382    // We should also do if the section name is NULL or function is declared in
383    // discardable section.
384    SwitchToSection(TAI->SectionForGlobal(F));
385  } else {
386    SwitchToDataSection(JumpTableDataSection);
387    JTInDiffSection = true;
388  }
389
390  EmitAlignment(Log2_32(MJTI->getAlignment()));
391
392  for (unsigned i = 0, e = JT.size(); i != e; ++i) {
393    const std::vector<MachineBasicBlock*> &JTBBs = JT[i].MBBs;
394
395    // If this jump table was deleted, ignore it.
396    if (JTBBs.empty()) continue;
397
398    // For PIC codegen, if possible we want to use the SetDirective to reduce
399    // the number of relocations the assembler will generate for the jump table.
400    // Set directives are all printed before the jump table itself.
401    SmallPtrSet<MachineBasicBlock*, 16> EmittedSets;
402    if (TAI->getSetDirective() && IsPic)
403      for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
404        if (EmittedSets.insert(JTBBs[ii]))
405          printPICJumpTableSetLabel(i, JTBBs[ii]);
406
407    // On some targets (e.g. darwin) we want to emit two consequtive labels
408    // before each jump table.  The first label is never referenced, but tells
409    // the assembler and linker the extents of the jump table object.  The
410    // second label is actually referenced by the code.
411    if (JTInDiffSection) {
412      if (const char *JTLabelPrefix = TAI->getJumpTableSpecialLabelPrefix())
413        O << JTLabelPrefix << "JTI" << getFunctionNumber() << '_' << i << ":\n";
414    }
415
416    O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
417      << '_' << i << ":\n";
418
419    for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
420      printPICJumpTableEntry(MJTI, JTBBs[ii], i);
421      O << '\n';
422    }
423  }
424}
425
426void AsmPrinter::printPICJumpTableEntry(const MachineJumpTableInfo *MJTI,
427                                        const MachineBasicBlock *MBB,
428                                        unsigned uid)  const {
429  bool IsPic = TM.getRelocationModel() == Reloc::PIC_;
430
431  // Use JumpTableDirective otherwise honor the entry size from the jump table
432  // info.
433  const char *JTEntryDirective = TAI->getJumpTableDirective();
434  bool HadJTEntryDirective = JTEntryDirective != NULL;
435  if (!HadJTEntryDirective) {
436    JTEntryDirective = MJTI->getEntrySize() == 4 ?
437      TAI->getData32bitsDirective() : TAI->getData64bitsDirective();
438  }
439
440  O << JTEntryDirective << ' ';
441
442  // If we have emitted set directives for the jump table entries, print
443  // them rather than the entries themselves.  If we're emitting PIC, then
444  // emit the table entries as differences between two text section labels.
445  // If we're emitting non-PIC code, then emit the entries as direct
446  // references to the target basic blocks.
447  if (IsPic) {
448    if (TAI->getSetDirective()) {
449      O << TAI->getPrivateGlobalPrefix() << getFunctionNumber()
450        << '_' << uid << "_set_" << MBB->getNumber();
451    } else {
452      printBasicBlockLabel(MBB, false, false, false);
453      // If the arch uses custom Jump Table directives, don't calc relative to
454      // JT
455      if (!HadJTEntryDirective)
456        O << '-' << TAI->getPrivateGlobalPrefix() << "JTI"
457          << getFunctionNumber() << '_' << uid;
458    }
459  } else {
460    printBasicBlockLabel(MBB, false, false, false);
461  }
462}
463
464
465/// EmitSpecialLLVMGlobal - Check to see if the specified global is a
466/// special global used by LLVM.  If so, emit it and return true, otherwise
467/// do nothing and return false.
468bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
469  if (GV->getName() == "llvm.used") {
470    if (TAI->getUsedDirective() != 0)    // No need to emit this at all.
471      EmitLLVMUsedList(GV->getInitializer());
472    return true;
473  }
474
475  // Ignore debug and non-emitted data.
476  if (GV->getSection() == "llvm.metadata" ||
477      GV->hasAvailableExternallyLinkage())
478    return true;
479
480  if (!GV->hasAppendingLinkage()) return false;
481
482  assert(GV->hasInitializer() && "Not a special LLVM global!");
483
484  const TargetData *TD = TM.getTargetData();
485  unsigned Align = Log2_32(TD->getPointerPrefAlignment());
486  if (GV->getName() == "llvm.global_ctors") {
487    SwitchToDataSection(TAI->getStaticCtorsSection());
488    EmitAlignment(Align, 0);
489    EmitXXStructorList(GV->getInitializer());
490    return true;
491  }
492
493  if (GV->getName() == "llvm.global_dtors") {
494    SwitchToDataSection(TAI->getStaticDtorsSection());
495    EmitAlignment(Align, 0);
496    EmitXXStructorList(GV->getInitializer());
497    return true;
498  }
499
500  return false;
501}
502
503/// EmitLLVMUsedList - For targets that define a TAI::UsedDirective, mark each
504/// global in the specified llvm.used list for which emitUsedDirectiveFor
505/// is true, as being used with this directive.
506void AsmPrinter::EmitLLVMUsedList(Constant *List) {
507  const char *Directive = TAI->getUsedDirective();
508
509  // Should be an array of 'i8*'.
510  ConstantArray *InitList = dyn_cast<ConstantArray>(List);
511  if (InitList == 0) return;
512
513  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
514    const GlobalValue *GV =
515      dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
516    if (GV && TAI->emitUsedDirectiveFor(GV, Mang)) {
517      O << Directive;
518      EmitConstantValueOnly(InitList->getOperand(i));
519      O << '\n';
520    }
521  }
522}
523
524/// EmitXXStructorList - Emit the ctor or dtor list.  This just prints out the
525/// function pointers, ignoring the init priority.
526void AsmPrinter::EmitXXStructorList(Constant *List) {
527  // Should be an array of '{ int, void ()* }' structs.  The first value is the
528  // init priority, which we ignore.
529  if (!isa<ConstantArray>(List)) return;
530  ConstantArray *InitList = cast<ConstantArray>(List);
531  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
532    if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
533      if (CS->getNumOperands() != 2) return;  // Not array of 2-element structs.
534
535      if (CS->getOperand(1)->isNullValue())
536        return;  // Found a null terminator, exit printing.
537      // Emit the function pointer.
538      EmitGlobalConstant(CS->getOperand(1));
539    }
540}
541
542/// getGlobalLinkName - Returns the asm/link name of of the specified
543/// global variable.  Should be overridden by each target asm printer to
544/// generate the appropriate value.
545const std::string &AsmPrinter::getGlobalLinkName(const GlobalVariable *GV,
546                                                 std::string &LinkName) const {
547  if (isa<Function>(GV)) {
548    LinkName += TAI->getFunctionAddrPrefix();
549    LinkName += Mang->getMangledName(GV);
550    LinkName += TAI->getFunctionAddrSuffix();
551  } else {
552    LinkName += TAI->getGlobalVarAddrPrefix();
553    LinkName += Mang->getMangledName(GV);
554    LinkName += TAI->getGlobalVarAddrSuffix();
555  }
556
557  return LinkName;
558}
559
560/// EmitExternalGlobal - Emit the external reference to a global variable.
561/// Should be overridden if an indirect reference should be used.
562void AsmPrinter::EmitExternalGlobal(const GlobalVariable *GV) {
563  std::string GLN;
564  O << getGlobalLinkName(GV, GLN);
565}
566
567
568
569//===----------------------------------------------------------------------===//
570/// LEB 128 number encoding.
571
572/// PrintULEB128 - Print a series of hexidecimal values (separated by commas)
573/// representing an unsigned leb128 value.
574void AsmPrinter::PrintULEB128(unsigned Value) const {
575  char Buffer[20];
576  do {
577    unsigned char Byte = static_cast<unsigned char>(Value & 0x7f);
578    Value >>= 7;
579    if (Value) Byte |= 0x80;
580    O << "0x" << utohex_buffer(Byte, Buffer+20);
581    if (Value) O << ", ";
582  } while (Value);
583}
584
585/// PrintSLEB128 - Print a series of hexidecimal values (separated by commas)
586/// representing a signed leb128 value.
587void AsmPrinter::PrintSLEB128(int Value) const {
588  int Sign = Value >> (8 * sizeof(Value) - 1);
589  bool IsMore;
590  char Buffer[20];
591
592  do {
593    unsigned char Byte = static_cast<unsigned char>(Value & 0x7f);
594    Value >>= 7;
595    IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0;
596    if (IsMore) Byte |= 0x80;
597    O << "0x" << utohex_buffer(Byte, Buffer+20);
598    if (IsMore) O << ", ";
599  } while (IsMore);
600}
601
602//===--------------------------------------------------------------------===//
603// Emission and print routines
604//
605
606/// PrintHex - Print a value as a hexidecimal value.
607///
608void AsmPrinter::PrintHex(int Value) const {
609  char Buffer[20];
610  O << "0x" << utohex_buffer(static_cast<unsigned>(Value), Buffer+20);
611}
612
613/// EOL - Print a newline character to asm stream.  If a comment is present
614/// then it will be printed first.  Comments should not contain '\n'.
615void AsmPrinter::EOL() const {
616  O << '\n';
617}
618
619void AsmPrinter::EOL(const std::string &Comment) const {
620  if (VerboseAsm && !Comment.empty()) {
621    O << '\t'
622      << TAI->getCommentString()
623      << ' '
624      << Comment;
625  }
626  O << '\n';
627}
628
629void AsmPrinter::EOL(const char* Comment) const {
630  if (VerboseAsm && *Comment) {
631    O << '\t'
632      << TAI->getCommentString()
633      << ' '
634      << Comment;
635  }
636  O << '\n';
637}
638
639/// EmitULEB128Bytes - Emit an assembler byte data directive to compose an
640/// unsigned leb128 value.
641void AsmPrinter::EmitULEB128Bytes(unsigned Value) const {
642  if (TAI->hasLEB128()) {
643    O << "\t.uleb128\t"
644      << Value;
645  } else {
646    O << TAI->getData8bitsDirective();
647    PrintULEB128(Value);
648  }
649}
650
651/// EmitSLEB128Bytes - print an assembler byte data directive to compose a
652/// signed leb128 value.
653void AsmPrinter::EmitSLEB128Bytes(int Value) const {
654  if (TAI->hasLEB128()) {
655    O << "\t.sleb128\t"
656      << Value;
657  } else {
658    O << TAI->getData8bitsDirective();
659    PrintSLEB128(Value);
660  }
661}
662
663/// EmitInt8 - Emit a byte directive and value.
664///
665void AsmPrinter::EmitInt8(int Value) const {
666  O << TAI->getData8bitsDirective();
667  PrintHex(Value & 0xFF);
668}
669
670/// EmitInt16 - Emit a short directive and value.
671///
672void AsmPrinter::EmitInt16(int Value) const {
673  O << TAI->getData16bitsDirective();
674  PrintHex(Value & 0xFFFF);
675}
676
677/// EmitInt32 - Emit a long directive and value.
678///
679void AsmPrinter::EmitInt32(int Value) const {
680  O << TAI->getData32bitsDirective();
681  PrintHex(Value);
682}
683
684/// EmitInt64 - Emit a long long directive and value.
685///
686void AsmPrinter::EmitInt64(uint64_t Value) const {
687  if (TAI->getData64bitsDirective()) {
688    O << TAI->getData64bitsDirective();
689    PrintHex(Value);
690  } else {
691    if (TM.getTargetData()->isBigEndian()) {
692      EmitInt32(unsigned(Value >> 32)); O << '\n';
693      EmitInt32(unsigned(Value));
694    } else {
695      EmitInt32(unsigned(Value)); O << '\n';
696      EmitInt32(unsigned(Value >> 32));
697    }
698  }
699}
700
701/// toOctal - Convert the low order bits of X into an octal digit.
702///
703static inline char toOctal(int X) {
704  return (X&7)+'0';
705}
706
707/// printStringChar - Print a char, escaped if necessary.
708///
709static void printStringChar(formatted_raw_ostream &O, unsigned char C) {
710  if (C == '"') {
711    O << "\\\"";
712  } else if (C == '\\') {
713    O << "\\\\";
714  } else if (isprint((unsigned char)C)) {
715    O << C;
716  } else {
717    switch(C) {
718    case '\b': O << "\\b"; break;
719    case '\f': O << "\\f"; break;
720    case '\n': O << "\\n"; break;
721    case '\r': O << "\\r"; break;
722    case '\t': O << "\\t"; break;
723    default:
724      O << '\\';
725      O << toOctal(C >> 6);
726      O << toOctal(C >> 3);
727      O << toOctal(C >> 0);
728      break;
729    }
730  }
731}
732
733/// EmitString - Emit a string with quotes and a null terminator.
734/// Special characters are emitted properly.
735/// \literal (Eg. '\t') \endliteral
736void AsmPrinter::EmitString(const std::string &String) const {
737  EmitString(String.c_str(), String.size());
738}
739
740void AsmPrinter::EmitString(const char *String, unsigned Size) const {
741  const char* AscizDirective = TAI->getAscizDirective();
742  if (AscizDirective)
743    O << AscizDirective;
744  else
745    O << TAI->getAsciiDirective();
746  O << '\"';
747  for (unsigned i = 0; i < Size; ++i)
748    printStringChar(O, String[i]);
749  if (AscizDirective)
750    O << '\"';
751  else
752    O << "\\0\"";
753}
754
755
756/// EmitFile - Emit a .file directive.
757void AsmPrinter::EmitFile(unsigned Number, const std::string &Name) const {
758  O << "\t.file\t" << Number << " \"";
759  for (unsigned i = 0, N = Name.size(); i < N; ++i)
760    printStringChar(O, Name[i]);
761  O << '\"';
762}
763
764
765//===----------------------------------------------------------------------===//
766
767// EmitAlignment - Emit an alignment directive to the specified power of
768// two boundary.  For example, if you pass in 3 here, you will get an 8
769// byte alignment.  If a global value is specified, and if that global has
770// an explicit alignment requested, it will unconditionally override the
771// alignment request.  However, if ForcedAlignBits is specified, this value
772// has final say: the ultimate alignment will be the max of ForcedAlignBits
773// and the alignment computed with NumBits and the global.
774//
775// The algorithm is:
776//     Align = NumBits;
777//     if (GV && GV->hasalignment) Align = GV->getalignment();
778//     Align = std::max(Align, ForcedAlignBits);
779//
780void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
781                               unsigned ForcedAlignBits,
782                               bool UseFillExpr) const {
783  if (GV && GV->getAlignment())
784    NumBits = Log2_32(GV->getAlignment());
785  NumBits = std::max(NumBits, ForcedAlignBits);
786
787  if (NumBits == 0) return;   // No need to emit alignment.
788  if (TAI->getAlignmentIsInBytes()) NumBits = 1 << NumBits;
789  O << TAI->getAlignDirective() << NumBits;
790
791  unsigned FillValue = TAI->getTextAlignFillValue();
792  UseFillExpr &= IsInTextSection && FillValue;
793  if (UseFillExpr) {
794    O << ',';
795    PrintHex(FillValue);
796  }
797  O << '\n';
798}
799
800
801/// EmitZeros - Emit a block of zeros.
802///
803void AsmPrinter::EmitZeros(uint64_t NumZeros, unsigned AddrSpace) const {
804  if (NumZeros) {
805    if (TAI->getZeroDirective()) {
806      O << TAI->getZeroDirective() << NumZeros;
807      if (TAI->getZeroDirectiveSuffix())
808        O << TAI->getZeroDirectiveSuffix();
809      O << '\n';
810    } else {
811      for (; NumZeros; --NumZeros)
812        O << TAI->getData8bitsDirective(AddrSpace) << "0\n";
813    }
814  }
815}
816
817// Print out the specified constant, without a storage class.  Only the
818// constants valid in constant expressions can occur here.
819void AsmPrinter::EmitConstantValueOnly(const Constant *CV) {
820  if (CV->isNullValue() || isa<UndefValue>(CV))
821    O << '0';
822  else if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
823    O << CI->getZExtValue();
824  } else if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV)) {
825    // This is a constant address for a global variable or function. Use the
826    // name of the variable or function as the address value, possibly
827    // decorating it with GlobalVarAddrPrefix/Suffix or
828    // FunctionAddrPrefix/Suffix (these all default to "" )
829    if (isa<Function>(GV)) {
830      O << TAI->getFunctionAddrPrefix()
831        << Mang->getMangledName(GV)
832        << TAI->getFunctionAddrSuffix();
833    } else {
834      O << TAI->getGlobalVarAddrPrefix()
835        << Mang->getMangledName(GV)
836        << TAI->getGlobalVarAddrSuffix();
837    }
838  } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
839    const TargetData *TD = TM.getTargetData();
840    unsigned Opcode = CE->getOpcode();
841    switch (Opcode) {
842    case Instruction::GetElementPtr: {
843      // generate a symbolic expression for the byte address
844      const Constant *ptrVal = CE->getOperand(0);
845      SmallVector<Value*, 8> idxVec(CE->op_begin()+1, CE->op_end());
846      if (int64_t Offset = TD->getIndexedOffset(ptrVal->getType(), &idxVec[0],
847                                                idxVec.size())) {
848        // Truncate/sext the offset to the pointer size.
849        if (TD->getPointerSizeInBits() != 64) {
850          int SExtAmount = 64-TD->getPointerSizeInBits();
851          Offset = (Offset << SExtAmount) >> SExtAmount;
852        }
853
854        if (Offset)
855          O << '(';
856        EmitConstantValueOnly(ptrVal);
857        if (Offset > 0)
858          O << ") + " << Offset;
859        else if (Offset < 0)
860          O << ") - " << -Offset;
861      } else {
862        EmitConstantValueOnly(ptrVal);
863      }
864      break;
865    }
866    case Instruction::Trunc:
867    case Instruction::ZExt:
868    case Instruction::SExt:
869    case Instruction::FPTrunc:
870    case Instruction::FPExt:
871    case Instruction::UIToFP:
872    case Instruction::SIToFP:
873    case Instruction::FPToUI:
874    case Instruction::FPToSI:
875      llvm_unreachable("FIXME: Don't yet support this kind of constant cast expr");
876      break;
877    case Instruction::BitCast:
878      return EmitConstantValueOnly(CE->getOperand(0));
879
880    case Instruction::IntToPtr: {
881      // Handle casts to pointers by changing them into casts to the appropriate
882      // integer type.  This promotes constant folding and simplifies this code.
883      Constant *Op = CE->getOperand(0);
884      Op = ConstantExpr::getIntegerCast(Op, TD->getIntPtrType(), false/*ZExt*/);
885      return EmitConstantValueOnly(Op);
886    }
887
888
889    case Instruction::PtrToInt: {
890      // Support only foldable casts to/from pointers that can be eliminated by
891      // changing the pointer to the appropriately sized integer type.
892      Constant *Op = CE->getOperand(0);
893      const Type *Ty = CE->getType();
894
895      // We can emit the pointer value into this slot if the slot is an
896      // integer slot greater or equal to the size of the pointer.
897      if (TD->getTypeAllocSize(Ty) >= TD->getTypeAllocSize(Op->getType()))
898        return EmitConstantValueOnly(Op);
899
900      O << "((";
901      EmitConstantValueOnly(Op);
902      APInt ptrMask = APInt::getAllOnesValue(TD->getTypeAllocSizeInBits(Ty));
903
904      SmallString<40> S;
905      ptrMask.toStringUnsigned(S);
906      O << ") & " << S.c_str() << ')';
907      break;
908    }
909    case Instruction::Add:
910    case Instruction::Sub:
911    case Instruction::And:
912    case Instruction::Or:
913    case Instruction::Xor:
914      O << '(';
915      EmitConstantValueOnly(CE->getOperand(0));
916      O << ')';
917      switch (Opcode) {
918      case Instruction::Add:
919       O << " + ";
920       break;
921      case Instruction::Sub:
922       O << " - ";
923       break;
924      case Instruction::And:
925       O << " & ";
926       break;
927      case Instruction::Or:
928       O << " | ";
929       break;
930      case Instruction::Xor:
931       O << " ^ ";
932       break;
933      default:
934       break;
935      }
936      O << '(';
937      EmitConstantValueOnly(CE->getOperand(1));
938      O << ')';
939      break;
940    default:
941      llvm_unreachable("Unsupported operator!");
942    }
943  } else {
944    llvm_unreachable("Unknown constant value!");
945  }
946}
947
948/// printAsCString - Print the specified array as a C compatible string, only if
949/// the predicate isString is true.
950///
951static void printAsCString(formatted_raw_ostream &O, const ConstantArray *CVA,
952                           unsigned LastElt) {
953  assert(CVA->isString() && "Array is not string compatible!");
954
955  O << '\"';
956  for (unsigned i = 0; i != LastElt; ++i) {
957    unsigned char C =
958        (unsigned char)cast<ConstantInt>(CVA->getOperand(i))->getZExtValue();
959    printStringChar(O, C);
960  }
961  O << '\"';
962}
963
964/// EmitString - Emit a zero-byte-terminated string constant.
965///
966void AsmPrinter::EmitString(const ConstantArray *CVA) const {
967  unsigned NumElts = CVA->getNumOperands();
968  if (TAI->getAscizDirective() && NumElts &&
969      cast<ConstantInt>(CVA->getOperand(NumElts-1))->getZExtValue() == 0) {
970    O << TAI->getAscizDirective();
971    printAsCString(O, CVA, NumElts-1);
972  } else {
973    O << TAI->getAsciiDirective();
974    printAsCString(O, CVA, NumElts);
975  }
976  O << '\n';
977}
978
979void AsmPrinter::EmitGlobalConstantArray(const ConstantArray *CVA,
980                                         unsigned AddrSpace) {
981  if (CVA->isString()) {
982    EmitString(CVA);
983  } else { // Not a string.  Print the values in successive locations
984    for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i)
985      EmitGlobalConstant(CVA->getOperand(i), AddrSpace);
986  }
987}
988
989void AsmPrinter::EmitGlobalConstantVector(const ConstantVector *CP) {
990  const VectorType *PTy = CP->getType();
991
992  for (unsigned I = 0, E = PTy->getNumElements(); I < E; ++I)
993    EmitGlobalConstant(CP->getOperand(I));
994}
995
996void AsmPrinter::EmitGlobalConstantStruct(const ConstantStruct *CVS,
997                                          unsigned AddrSpace) {
998  // Print the fields in successive locations. Pad to align if needed!
999  const TargetData *TD = TM.getTargetData();
1000  unsigned Size = TD->getTypeAllocSize(CVS->getType());
1001  const StructLayout *cvsLayout = TD->getStructLayout(CVS->getType());
1002  uint64_t sizeSoFar = 0;
1003  for (unsigned i = 0, e = CVS->getNumOperands(); i != e; ++i) {
1004    const Constant* field = CVS->getOperand(i);
1005
1006    // Check if padding is needed and insert one or more 0s.
1007    uint64_t fieldSize = TD->getTypeAllocSize(field->getType());
1008    uint64_t padSize = ((i == e-1 ? Size : cvsLayout->getElementOffset(i+1))
1009                        - cvsLayout->getElementOffset(i)) - fieldSize;
1010    sizeSoFar += fieldSize + padSize;
1011
1012    // Now print the actual field value.
1013    EmitGlobalConstant(field, AddrSpace);
1014
1015    // Insert padding - this may include padding to increase the size of the
1016    // current field up to the ABI size (if the struct is not packed) as well
1017    // as padding to ensure that the next field starts at the right offset.
1018    EmitZeros(padSize, AddrSpace);
1019  }
1020  assert(sizeSoFar == cvsLayout->getSizeInBytes() &&
1021         "Layout of constant struct may be incorrect!");
1022}
1023
1024void AsmPrinter::EmitGlobalConstantFP(const ConstantFP *CFP,
1025                                      unsigned AddrSpace) {
1026  // FP Constants are printed as integer constants to avoid losing
1027  // precision...
1028  const TargetData *TD = TM.getTargetData();
1029  if (CFP->getType() == Type::DoubleTy) {
1030    double Val = CFP->getValueAPF().convertToDouble();  // for comment only
1031    uint64_t i = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1032    if (TAI->getData64bitsDirective(AddrSpace)) {
1033      O << TAI->getData64bitsDirective(AddrSpace) << i;
1034      if (VerboseAsm)
1035        O << '\t' << TAI->getCommentString() << " double value: " << Val;
1036      O << '\n';
1037    } else if (TD->isBigEndian()) {
1038      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i >> 32);
1039      if (VerboseAsm)
1040        O << '\t' << TAI->getCommentString()
1041          << " double most significant word " << Val;
1042      O << '\n';
1043      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i);
1044      if (VerboseAsm)
1045        O << '\t' << TAI->getCommentString()
1046          << " double least significant word " << Val;
1047      O << '\n';
1048    } else {
1049      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i);
1050      if (VerboseAsm)
1051        O << '\t' << TAI->getCommentString()
1052          << " double least significant word " << Val;
1053      O << '\n';
1054      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i >> 32);
1055      if (VerboseAsm)
1056        O << '\t' << TAI->getCommentString()
1057          << " double most significant word " << Val;
1058      O << '\n';
1059    }
1060    return;
1061  } else if (CFP->getType() == Type::FloatTy) {
1062    float Val = CFP->getValueAPF().convertToFloat();  // for comment only
1063    O << TAI->getData32bitsDirective(AddrSpace)
1064      << CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1065    if (VerboseAsm)
1066      O << '\t' << TAI->getCommentString() << " float " << Val;
1067    O << '\n';
1068    return;
1069  } else if (CFP->getType() == Type::X86_FP80Ty) {
1070    // all long double variants are printed as hex
1071    // api needed to prevent premature destruction
1072    APInt api = CFP->getValueAPF().bitcastToAPInt();
1073    const uint64_t *p = api.getRawData();
1074    // Convert to double so we can print the approximate val as a comment.
1075    APFloat DoubleVal = CFP->getValueAPF();
1076    bool ignored;
1077    DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1078                      &ignored);
1079    if (TD->isBigEndian()) {
1080      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[1]);
1081      if (VerboseAsm)
1082        O << '\t' << TAI->getCommentString()
1083          << " long double most significant halfword of ~"
1084          << DoubleVal.convertToDouble();
1085      O << '\n';
1086      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 48);
1087      if (VerboseAsm)
1088        O << '\t' << TAI->getCommentString() << " long double next halfword";
1089      O << '\n';
1090      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 32);
1091      if (VerboseAsm)
1092        O << '\t' << TAI->getCommentString() << " long double next halfword";
1093      O << '\n';
1094      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 16);
1095      if (VerboseAsm)
1096        O << '\t' << TAI->getCommentString() << " long double next halfword";
1097      O << '\n';
1098      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0]);
1099      if (VerboseAsm)
1100        O << '\t' << TAI->getCommentString()
1101          << " long double least significant halfword";
1102      O << '\n';
1103     } else {
1104      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0]);
1105      if (VerboseAsm)
1106        O << '\t' << TAI->getCommentString()
1107          << " long double least significant halfword of ~"
1108          << DoubleVal.convertToDouble();
1109      O << '\n';
1110      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 16);
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] >> 32);
1116      if (VerboseAsm)
1117        O << '\t' << TAI->getCommentString()
1118          << " long double next halfword";
1119      O << '\n';
1120      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 48);
1121      if (VerboseAsm)
1122        O << '\t' << TAI->getCommentString()
1123          << " long double next halfword";
1124      O << '\n';
1125      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[1]);
1126      if (VerboseAsm)
1127        O << '\t' << TAI->getCommentString()
1128          << " long double most significant halfword";
1129      O << '\n';
1130    }
1131    EmitZeros(TD->getTypeAllocSize(Type::X86_FP80Ty) -
1132              TD->getTypeStoreSize(Type::X86_FP80Ty), AddrSpace);
1133    return;
1134  } else if (CFP->getType() == Type::PPC_FP128Ty) {
1135    // all long double variants are printed as hex
1136    // api needed to prevent premature destruction
1137    APInt api = CFP->getValueAPF().bitcastToAPInt();
1138    const uint64_t *p = api.getRawData();
1139    if (TD->isBigEndian()) {
1140      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0] >> 32);
1141      if (VerboseAsm)
1142        O << '\t' << TAI->getCommentString()
1143          << " long double most significant word";
1144      O << '\n';
1145      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0]);
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] >> 32);
1151      if (VerboseAsm)
1152        O << '\t' << TAI->getCommentString()
1153          << " long double next word";
1154      O << '\n';
1155      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1]);
1156      if (VerboseAsm)
1157        O << '\t' << TAI->getCommentString()
1158          << " long double least significant word";
1159      O << '\n';
1160     } else {
1161      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1]);
1162      if (VerboseAsm)
1163        O << '\t' << TAI->getCommentString()
1164          << " long double least significant word";
1165      O << '\n';
1166      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1] >> 32);
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]);
1172      if (VerboseAsm)
1173        O << '\t' << TAI->getCommentString()
1174          << " long double next word";
1175      O << '\n';
1176      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0] >> 32);
1177      if (VerboseAsm)
1178        O << '\t' << TAI->getCommentString()
1179          << " long double most significant word";
1180      O << '\n';
1181    }
1182    return;
1183  } else llvm_unreachable("Floating point constant type not handled");
1184}
1185
1186void AsmPrinter::EmitGlobalConstantLargeInt(const ConstantInt *CI,
1187                                            unsigned AddrSpace) {
1188  const TargetData *TD = TM.getTargetData();
1189  unsigned BitWidth = CI->getBitWidth();
1190  assert(isPowerOf2_32(BitWidth) &&
1191         "Non-power-of-2-sized integers not handled!");
1192
1193  // We don't expect assemblers to support integer data directives
1194  // for more than 64 bits, so we emit the data in at most 64-bit
1195  // quantities at a time.
1196  const uint64_t *RawData = CI->getValue().getRawData();
1197  for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1198    uint64_t Val;
1199    if (TD->isBigEndian())
1200      Val = RawData[e - i - 1];
1201    else
1202      Val = RawData[i];
1203
1204    if (TAI->getData64bitsDirective(AddrSpace))
1205      O << TAI->getData64bitsDirective(AddrSpace) << Val << '\n';
1206    else if (TD->isBigEndian()) {
1207      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val >> 32);
1208      if (VerboseAsm)
1209        O << '\t' << TAI->getCommentString()
1210          << " Double-word most significant word " << Val;
1211      O << '\n';
1212      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val);
1213      if (VerboseAsm)
1214        O << '\t' << TAI->getCommentString()
1215          << " Double-word least significant word " << Val;
1216      O << '\n';
1217    } else {
1218      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val);
1219      if (VerboseAsm)
1220        O << '\t' << TAI->getCommentString()
1221          << " Double-word least significant word " << Val;
1222      O << '\n';
1223      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val >> 32);
1224      if (VerboseAsm)
1225        O << '\t' << TAI->getCommentString()
1226          << " Double-word most significant word " << Val;
1227      O << '\n';
1228    }
1229  }
1230}
1231
1232/// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1233void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1234  const TargetData *TD = TM.getTargetData();
1235  const Type *type = CV->getType();
1236  unsigned Size = TD->getTypeAllocSize(type);
1237
1238  if (CV->isNullValue() || isa<UndefValue>(CV)) {
1239    EmitZeros(Size, AddrSpace);
1240    return;
1241  } else if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) {
1242    EmitGlobalConstantArray(CVA , AddrSpace);
1243    return;
1244  } else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) {
1245    EmitGlobalConstantStruct(CVS, AddrSpace);
1246    return;
1247  } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) {
1248    EmitGlobalConstantFP(CFP, AddrSpace);
1249    return;
1250  } else if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1251    // Small integers are handled below; large integers are handled here.
1252    if (Size > 4) {
1253      EmitGlobalConstantLargeInt(CI, AddrSpace);
1254      return;
1255    }
1256  } else if (const ConstantVector *CP = dyn_cast<ConstantVector>(CV)) {
1257    EmitGlobalConstantVector(CP);
1258    return;
1259  }
1260
1261  printDataDirective(type, AddrSpace);
1262  EmitConstantValueOnly(CV);
1263  if (VerboseAsm) {
1264    if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1265      SmallString<40> S;
1266      CI->getValue().toStringUnsigned(S, 16);
1267      O << "\t\t\t" << TAI->getCommentString() << " 0x" << S.c_str();
1268    }
1269  }
1270  O << '\n';
1271}
1272
1273void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1274  // Target doesn't support this yet!
1275  llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1276}
1277
1278/// PrintSpecial - Print information related to the specified machine instr
1279/// that is independent of the operand, and may be independent of the instr
1280/// itself.  This can be useful for portably encoding the comment character
1281/// or other bits of target-specific knowledge into the asmstrings.  The
1282/// syntax used is ${:comment}.  Targets can override this to add support
1283/// for their own strange codes.
1284void AsmPrinter::PrintSpecial(const MachineInstr *MI, const char *Code) const {
1285  if (!strcmp(Code, "private")) {
1286    O << TAI->getPrivateGlobalPrefix();
1287  } else if (!strcmp(Code, "comment")) {
1288    if (VerboseAsm)
1289      O << TAI->getCommentString();
1290  } else if (!strcmp(Code, "uid")) {
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 LastFn instruction, bump the counter.
1296    if (LastMI != MI || LastFn != ThisF) {
1297      ++Counter;
1298      LastMI = MI;
1299      LastFn = ThisF;
1300    }
1301    O << Counter;
1302  } else {
1303    std::string msg;
1304    raw_string_ostream Msg(msg);
1305    Msg << "Unknown special formatter '" << Code
1306         << "' for machine instr: " << *MI;
1307    llvm_report_error(Msg.str());
1308  }
1309}
1310
1311/// processDebugLoc - Processes the debug information of each machine
1312/// instruction's DebugLoc.
1313void AsmPrinter::processDebugLoc(DebugLoc DL) {
1314  if (TAI->doesSupportDebugInformation() && DW->ShouldEmitDwarfDebug()) {
1315    if (!DL.isUnknown()) {
1316      DebugLocTuple CurDLT = MF->getDebugLocTuple(DL);
1317
1318      if (CurDLT.CompileUnit != 0 && PrevDLT != CurDLT)
1319        printLabel(DW->RecordSourceLine(CurDLT.Line, CurDLT.Col,
1320                                        DICompileUnit(CurDLT.CompileUnit)));
1321
1322      PrevDLT = CurDLT;
1323    }
1324  }
1325}
1326
1327/// printInlineAsm - This method formats and prints the specified machine
1328/// instruction that is an inline asm.
1329void AsmPrinter::printInlineAsm(const MachineInstr *MI) const {
1330  unsigned NumOperands = MI->getNumOperands();
1331
1332  // Count the number of register definitions.
1333  unsigned NumDefs = 0;
1334  for (; MI->getOperand(NumDefs).isReg() && MI->getOperand(NumDefs).isDef();
1335       ++NumDefs)
1336    assert(NumDefs != NumOperands-1 && "No asm string?");
1337
1338  assert(MI->getOperand(NumDefs).isSymbol() && "No asm string?");
1339
1340  // Disassemble the AsmStr, printing out the literal pieces, the operands, etc.
1341  const char *AsmStr = MI->getOperand(NumDefs).getSymbolName();
1342
1343  // If this asmstr is empty, just print the #APP/#NOAPP markers.
1344  // These are useful to see where empty asm's wound up.
1345  if (AsmStr[0] == 0) {
1346    O << TAI->getInlineAsmStart() << "\n\t" << TAI->getInlineAsmEnd() << '\n';
1347    return;
1348  }
1349
1350  O << TAI->getInlineAsmStart() << "\n\t";
1351
1352  // The variant of the current asmprinter.
1353  int AsmPrinterVariant = TAI->getAssemblerDialect();
1354
1355  int CurVariant = -1;            // The number of the {.|.|.} region we are in.
1356  const char *LastEmitted = AsmStr; // One past the last character emitted.
1357
1358  while (*LastEmitted) {
1359    switch (*LastEmitted) {
1360    default: {
1361      // Not a special case, emit the string section literally.
1362      const char *LiteralEnd = LastEmitted+1;
1363      while (*LiteralEnd && *LiteralEnd != '{' && *LiteralEnd != '|' &&
1364             *LiteralEnd != '}' && *LiteralEnd != '$' && *LiteralEnd != '\n')
1365        ++LiteralEnd;
1366      if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1367        O.write(LastEmitted, LiteralEnd-LastEmitted);
1368      LastEmitted = LiteralEnd;
1369      break;
1370    }
1371    case '\n':
1372      ++LastEmitted;   // Consume newline character.
1373      O << '\n';       // Indent code with newline.
1374      break;
1375    case '$': {
1376      ++LastEmitted;   // Consume '$' character.
1377      bool Done = true;
1378
1379      // Handle escapes.
1380      switch (*LastEmitted) {
1381      default: Done = false; break;
1382      case '$':     // $$ -> $
1383        if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1384          O << '$';
1385        ++LastEmitted;  // Consume second '$' character.
1386        break;
1387      case '(':             // $( -> same as GCC's { character.
1388        ++LastEmitted;      // Consume '(' character.
1389        if (CurVariant != -1) {
1390          llvm_report_error("Nested variants found in inline asm string: '"
1391                            + std::string(AsmStr) + "'");
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          llvm_report_error("Unterminated ${:foo} operand in inline asm string: '"
1427                            + std::string(AsmStr) + "'");
1428        }
1429
1430        std::string Val(StrStart, StrEnd);
1431        PrintSpecial(MI, Val.c_str());
1432        LastEmitted = StrEnd+1;
1433        break;
1434      }
1435
1436      const char *IDStart = LastEmitted;
1437      char *IDEnd;
1438      errno = 0;
1439      long Val = strtol(IDStart, &IDEnd, 10); // We only accept numbers for IDs.
1440      if (!isdigit(*IDStart) || (Val == 0 && errno == EINVAL)) {
1441        llvm_report_error("Bad $ operand number in inline asm string: '"
1442                          + std::string(AsmStr) + "'");
1443      }
1444      LastEmitted = IDEnd;
1445
1446      char Modifier[2] = { 0, 0 };
1447
1448      if (HasCurlyBraces) {
1449        // If we have curly braces, check for a modifier character.  This
1450        // supports syntax like ${0:u}, which correspond to "%u0" in GCC asm.
1451        if (*LastEmitted == ':') {
1452          ++LastEmitted;    // Consume ':' character.
1453          if (*LastEmitted == 0) {
1454            llvm_report_error("Bad ${:} expression in inline asm string: '"
1455                              + std::string(AsmStr) + "'");
1456          }
1457
1458          Modifier[0] = *LastEmitted;
1459          ++LastEmitted;    // Consume modifier character.
1460        }
1461
1462        if (*LastEmitted != '}') {
1463          llvm_report_error("Bad ${} expression in inline asm string: '"
1464                            + std::string(AsmStr) + "'");
1465        }
1466        ++LastEmitted;    // Consume '}' character.
1467      }
1468
1469      if ((unsigned)Val >= NumOperands-1) {
1470        llvm_report_error("Invalid $ operand number in inline asm string: '"
1471                          + std::string(AsmStr) + "'");
1472      }
1473
1474      // Okay, we finally have a value number.  Ask the target to print this
1475      // operand!
1476      if (CurVariant == -1 || CurVariant == AsmPrinterVariant) {
1477        unsigned OpNo = 1;
1478
1479        bool Error = false;
1480
1481        // Scan to find the machine operand number for the operand.
1482        for (; Val; --Val) {
1483          if (OpNo >= MI->getNumOperands()) break;
1484          unsigned OpFlags = MI->getOperand(OpNo).getImm();
1485          OpNo += InlineAsm::getNumOperandRegisters(OpFlags) + 1;
1486        }
1487
1488        if (OpNo >= MI->getNumOperands()) {
1489          Error = true;
1490        } else {
1491          unsigned OpFlags = MI->getOperand(OpNo).getImm();
1492          ++OpNo;  // Skip over the ID number.
1493
1494          if (Modifier[0]=='l')  // labels are target independent
1495            printBasicBlockLabel(MI->getOperand(OpNo).getMBB(),
1496                                 false, false, false);
1497          else {
1498            AsmPrinter *AP = const_cast<AsmPrinter*>(this);
1499            if ((OpFlags & 7) == 4) {
1500              Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant,
1501                                                Modifier[0] ? Modifier : 0);
1502            } else {
1503              Error = AP->PrintAsmOperand(MI, OpNo, AsmPrinterVariant,
1504                                          Modifier[0] ? Modifier : 0);
1505            }
1506          }
1507        }
1508        if (Error) {
1509          std::string msg;
1510          raw_string_ostream Msg(msg);
1511          Msg << "Invalid operand found in inline asm: '"
1512               << AsmStr << "'\n";
1513          MI->print(Msg);
1514          llvm_report_error(Msg.str());
1515        }
1516      }
1517      break;
1518    }
1519    }
1520  }
1521  O << "\n\t" << TAI->getInlineAsmEnd() << '\n';
1522}
1523
1524/// printImplicitDef - This method prints the specified machine instruction
1525/// that is an implicit def.
1526void AsmPrinter::printImplicitDef(const MachineInstr *MI) const {
1527  if (VerboseAsm)
1528    O << '\t' << TAI->getCommentString() << " implicit-def: "
1529      << TRI->getAsmName(MI->getOperand(0).getReg()) << '\n';
1530}
1531
1532/// printLabel - This method prints a local label used by debug and
1533/// exception handling tables.
1534void AsmPrinter::printLabel(const MachineInstr *MI) const {
1535  printLabel(MI->getOperand(0).getImm());
1536}
1537
1538void AsmPrinter::printLabel(unsigned Id) const {
1539  O << TAI->getPrivateGlobalPrefix() << "label" << Id << ":\n";
1540}
1541
1542/// printDeclare - This method prints a local variable declaration used by
1543/// debug tables.
1544/// FIXME: It doesn't really print anything rather it inserts a DebugVariable
1545/// entry into dwarf table.
1546void AsmPrinter::printDeclare(const MachineInstr *MI) const {
1547  unsigned FI = MI->getOperand(0).getIndex();
1548  GlobalValue *GV = MI->getOperand(1).getGlobal();
1549  DW->RecordVariable(cast<GlobalVariable>(GV), FI, MI);
1550}
1551
1552/// PrintAsmOperand - Print the specified operand of MI, an INLINEASM
1553/// instruction, using the specified assembler variant.  Targets should
1554/// overried this to format as appropriate.
1555bool AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
1556                                 unsigned AsmVariant, const char *ExtraCode) {
1557  // Target doesn't support this yet!
1558  return true;
1559}
1560
1561bool AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
1562                                       unsigned AsmVariant,
1563                                       const char *ExtraCode) {
1564  // Target doesn't support this yet!
1565  return true;
1566}
1567
1568/// printBasicBlockLabel - This method prints the label for the specified
1569/// MachineBasicBlock
1570void AsmPrinter::printBasicBlockLabel(const MachineBasicBlock *MBB,
1571                                      bool printAlign,
1572                                      bool printColon,
1573                                      bool printComment) const {
1574  if (printAlign) {
1575    unsigned Align = MBB->getAlignment();
1576    if (Align)
1577      EmitAlignment(Log2_32(Align));
1578  }
1579
1580  O << TAI->getPrivateGlobalPrefix() << "BB" << getFunctionNumber() << '_'
1581    << MBB->getNumber();
1582  if (printColon)
1583    O << ':';
1584  if (printComment && MBB->getBasicBlock())
1585    O << '\t' << TAI->getCommentString() << ' '
1586      << MBB->getBasicBlock()->getNameStart();
1587}
1588
1589/// printPICJumpTableSetLabel - This method prints a set label for the
1590/// specified MachineBasicBlock for a jumptable entry.
1591void AsmPrinter::printPICJumpTableSetLabel(unsigned uid,
1592                                           const MachineBasicBlock *MBB) const {
1593  if (!TAI->getSetDirective())
1594    return;
1595
1596  O << TAI->getSetDirective() << ' ' << TAI->getPrivateGlobalPrefix()
1597    << getFunctionNumber() << '_' << uid << "_set_" << MBB->getNumber() << ',';
1598  printBasicBlockLabel(MBB, false, false, false);
1599  O << '-' << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
1600    << '_' << uid << '\n';
1601}
1602
1603void AsmPrinter::printPICJumpTableSetLabel(unsigned uid, unsigned uid2,
1604                                           const MachineBasicBlock *MBB) const {
1605  if (!TAI->getSetDirective())
1606    return;
1607
1608  O << TAI->getSetDirective() << ' ' << TAI->getPrivateGlobalPrefix()
1609    << getFunctionNumber() << '_' << uid << '_' << uid2
1610    << "_set_" << MBB->getNumber() << ',';
1611  printBasicBlockLabel(MBB, false, false, false);
1612  O << '-' << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
1613    << '_' << uid << '_' << uid2 << '\n';
1614}
1615
1616/// printDataDirective - This method prints the asm directive for the
1617/// specified type.
1618void AsmPrinter::printDataDirective(const Type *type, unsigned AddrSpace) {
1619  const TargetData *TD = TM.getTargetData();
1620  switch (type->getTypeID()) {
1621  case Type::FloatTyID: case Type::DoubleTyID:
1622  case Type::X86_FP80TyID: case Type::FP128TyID: case Type::PPC_FP128TyID:
1623    assert(0 && "Should have already output floating point constant.");
1624  default:
1625    assert(0 && "Can't handle printing this type of thing");
1626  case Type::IntegerTyID: {
1627    unsigned BitWidth = cast<IntegerType>(type)->getBitWidth();
1628    if (BitWidth <= 8)
1629      O << TAI->getData8bitsDirective(AddrSpace);
1630    else if (BitWidth <= 16)
1631      O << TAI->getData16bitsDirective(AddrSpace);
1632    else if (BitWidth <= 32)
1633      O << TAI->getData32bitsDirective(AddrSpace);
1634    else if (BitWidth <= 64) {
1635      assert(TAI->getData64bitsDirective(AddrSpace) &&
1636             "Target cannot handle 64-bit constant exprs!");
1637      O << TAI->getData64bitsDirective(AddrSpace);
1638    } else {
1639      llvm_unreachable("Target cannot handle given data directive width!");
1640    }
1641    break;
1642  }
1643  case Type::PointerTyID:
1644    if (TD->getPointerSize() == 8) {
1645      assert(TAI->getData64bitsDirective(AddrSpace) &&
1646             "Target cannot handle 64-bit pointer exprs!");
1647      O << TAI->getData64bitsDirective(AddrSpace);
1648    } else if (TD->getPointerSize() == 2) {
1649      O << TAI->getData16bitsDirective(AddrSpace);
1650    } else if (TD->getPointerSize() == 1) {
1651      O << TAI->getData8bitsDirective(AddrSpace);
1652    } else {
1653      O << TAI->getData32bitsDirective(AddrSpace);
1654    }
1655    break;
1656  }
1657}
1658
1659void AsmPrinter::printVisibility(const std::string& Name,
1660                                 unsigned Visibility) const {
1661  if (Visibility == GlobalValue::HiddenVisibility) {
1662    if (const char *Directive = TAI->getHiddenDirective())
1663      O << Directive << Name << '\n';
1664  } else if (Visibility == GlobalValue::ProtectedVisibility) {
1665    if (const char *Directive = TAI->getProtectedDirective())
1666      O << Directive << Name << '\n';
1667  }
1668}
1669
1670void AsmPrinter::printOffset(int64_t Offset) const {
1671  if (Offset > 0)
1672    O << '+' << Offset;
1673  else if (Offset < 0)
1674    O << Offset;
1675}
1676
1677GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1678  if (!S->usesMetadata())
1679    return 0;
1680
1681  gcp_iterator GCPI = GCMetadataPrinters.find(S);
1682  if (GCPI != GCMetadataPrinters.end())
1683    return GCPI->second;
1684
1685  const char *Name = S->getName().c_str();
1686
1687  for (GCMetadataPrinterRegistry::iterator
1688         I = GCMetadataPrinterRegistry::begin(),
1689         E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1690    if (strcmp(Name, I->getName()) == 0) {
1691      GCMetadataPrinter *GMP = I->instantiate();
1692      GMP->S = S;
1693      GCMetadataPrinters.insert(std::make_pair(S, GMP));
1694      return GMP;
1695    }
1696
1697  cerr << "no GCMetadataPrinter registered for GC: " << Name << "\n";
1698  llvm_unreachable(0);
1699}
1700
1701/// EmitComments - Pretty-print comments for instructions
1702void AsmPrinter::EmitComments(const MachineInstr &MI) const
1703{
1704  if (!MI.getDebugLoc().isUnknown()) {
1705    DebugLocTuple DLT = MF->getDebugLocTuple(MI.getDebugLoc());
1706
1707    // Print source line info
1708    O.PadToColumn(TAI->getCommentColumn(), 1);
1709    O << TAI->getCommentString() << " SrcLine " << DLT.Line << ":" << DLT.Col;
1710  }
1711}
1712
1713/// EmitComments - Pretty-print comments for instructions
1714void AsmPrinter::EmitComments(const MCInst &MI) const
1715{
1716  if (!MI.getDebugLoc().isUnknown()) {
1717    DebugLocTuple DLT = MF->getDebugLocTuple(MI.getDebugLoc());
1718
1719    // Print source line info
1720    O.PadToColumn(TAI->getCommentColumn(), 1);
1721    O << TAI->getCommentString() << " SrcLine " << DLT.Line << ":" << DLT.Col;
1722  }
1723}
1724