AsmPrinter.cpp revision 7d696d80409aad20bb5da0fc4eccab941dd371d4 
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/ErrorHandling.h"
27#include "llvm/Support/Mangler.h"
28#include "llvm/Support/raw_ostream.h"
29#include "llvm/Target/TargetAsmInfo.h"
30#include "llvm/Target/TargetData.h"
31#include "llvm/Target/TargetLowering.h"
32#include "llvm/Target/TargetOptions.h"
33#include "llvm/Target/TargetRegisterInfo.h"
34#include "llvm/ADT/SmallPtrSet.h"
35#include "llvm/ADT/SmallString.h"
36#include "llvm/ADT/StringExtras.h"
37#include <cerrno>
38using namespace llvm;
39
40static cl::opt<cl::boolOrDefault>
41AsmVerbose("asm-verbose", cl::desc("Add comments to directives."),
42           cl::init(cl::BOU_UNSET));
43
44char AsmPrinter::ID = 0;
45AsmPrinter::AsmPrinter(raw_ostream &o, TargetMachine &tm,
46                       const TargetAsmInfo *T, bool VDef)
47  : MachineFunctionPass(&ID), FunctionNumber(0), O(o),
48    TM(tm), TAI(T), TRI(tm.getRegisterInfo()),
49    IsInTextSection(false), LastMI(0), LastFn(0), Counter(~0U),
50    PrevDLT(0, ~0U, ~0U) {
51  DW = 0; MMI = 0;
52  switch (AsmVerbose) {
53  case cl::BOU_UNSET: VerboseAsm = VDef;  break;
54  case cl::BOU_TRUE:  VerboseAsm = true;  break;
55  case cl::BOU_FALSE: VerboseAsm = false; break;
56  }
57}
58
59AsmPrinter::~AsmPrinter() {
60  for (gcp_iterator I = GCMetadataPrinters.begin(),
61                    E = GCMetadataPrinters.end(); I != E; ++I)
62    delete I->second;
63}
64
65/// SwitchToTextSection - Switch to the specified text section of the executable
66/// if we are not already in it!
67///
68void AsmPrinter::SwitchToTextSection(const char *NewSection,
69                                     const GlobalValue *GV) {
70  std::string NS;
71  if (GV && GV->hasSection())
72    NS = TAI->getSwitchToSectionDirective() + GV->getSection();
73  else
74    NS = NewSection;
75
76  // If we're already in this section, we're done.
77  if (CurrentSection == NS) return;
78
79  // Close the current section, if applicable.
80  if (TAI->getSectionEndDirectiveSuffix() && !CurrentSection.empty())
81    O << CurrentSection << TAI->getSectionEndDirectiveSuffix() << '\n';
82
83  CurrentSection = NS;
84
85  if (!CurrentSection.empty())
86    O << CurrentSection << TAI->getTextSectionStartSuffix() << '\n';
87
88  IsInTextSection = true;
89}
90
91/// SwitchToDataSection - Switch to the specified data section of the executable
92/// if we are not already in it!
93///
94void AsmPrinter::SwitchToDataSection(const char *NewSection,
95                                     const GlobalValue *GV) {
96  std::string NS;
97  if (GV && GV->hasSection())
98    NS = TAI->getSwitchToSectionDirective() + GV->getSection();
99  else
100    NS = NewSection;
101
102  // If we're already in this section, we're done.
103  if (CurrentSection == NS) return;
104
105  // Close the current section, if applicable.
106  if (TAI->getSectionEndDirectiveSuffix() && !CurrentSection.empty())
107    O << CurrentSection << TAI->getSectionEndDirectiveSuffix() << '\n';
108
109  CurrentSection = NS;
110
111  if (!CurrentSection.empty())
112    O << CurrentSection << TAI->getDataSectionStartSuffix() << '\n';
113
114  IsInTextSection = false;
115}
116
117/// SwitchToSection - Switch to the specified section of the executable if we
118/// are not already in it!
119void AsmPrinter::SwitchToSection(const Section* NS) {
120  const std::string& NewSection = NS->getName();
121
122  // If we're already in this section, we're done.
123  if (CurrentSection == NewSection) return;
124
125  // Close the current section, if applicable.
126  if (TAI->getSectionEndDirectiveSuffix() && !CurrentSection.empty())
127    O << CurrentSection << TAI->getSectionEndDirectiveSuffix() << '\n';
128
129  // FIXME: Make CurrentSection a Section* in the future
130  CurrentSection = NewSection;
131  CurrentSection_ = NS;
132
133  if (!CurrentSection.empty()) {
134    // If section is named we need to switch into it via special '.section'
135    // directive and also append funky flags. Otherwise - section name is just
136    // some magic assembler directive.
137    if (NS->isNamed())
138      O << TAI->getSwitchToSectionDirective()
139        << CurrentSection
140        << TAI->getSectionFlags(NS->getFlags());
141    else
142      O << CurrentSection;
143    O << TAI->getDataSectionStartSuffix() << '\n';
144  }
145
146  IsInTextSection = (NS->getFlags() & SectionFlags::Code);
147}
148
149void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
150  MachineFunctionPass::getAnalysisUsage(AU);
151  AU.addRequired<GCModuleInfo>();
152}
153
154bool AsmPrinter::doInitialization(Module &M) {
155  Mang = new Mangler(M, TAI->getGlobalPrefix(), TAI->getPrivateGlobalPrefix());
156
157  if (TAI->doesAllowQuotesInName())
158    Mang->setUseQuotes(true);
159
160  GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
161  assert(MI && "AsmPrinter didn't require GCModuleInfo?");
162
163  if (TAI->hasSingleParameterDotFile()) {
164    /* Very minimal debug info. It is ignored if we emit actual
165       debug info. If we don't, this at helps the user find where
166       a function came from. */
167    O << "\t.file\t\"" << M.getModuleIdentifier() << "\"\n";
168  }
169
170  for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
171    if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
172      MP->beginAssembly(O, *this, *TAI);
173
174  if (!M.getModuleInlineAsm().empty())
175    O << TAI->getCommentString() << " Start of file scope inline assembly\n"
176      << M.getModuleInlineAsm()
177      << '\n' << TAI->getCommentString()
178      << " End of file scope inline assembly\n";
179
180  SwitchToDataSection("");   // Reset back to no section.
181
182  if (TAI->doesSupportDebugInformation() ||
183      TAI->doesSupportExceptionHandling()) {
184    MMI = getAnalysisIfAvailable<MachineModuleInfo>();
185    if (MMI)
186      MMI->AnalyzeModule(M);
187    DW = getAnalysisIfAvailable<DwarfWriter>();
188    if (DW)
189      DW->BeginModule(&M, MMI, O, this, TAI);
190  }
191
192  return false;
193}
194
195bool AsmPrinter::doFinalization(Module &M) {
196  // Emit final debug information.
197  if (TAI->doesSupportDebugInformation() || TAI->doesSupportExceptionHandling())
198    DW->EndModule();
199
200  // If the target wants to know about weak references, print them all.
201  if (TAI->getWeakRefDirective()) {
202    // FIXME: This is not lazy, it would be nice to only print weak references
203    // to stuff that is actually used.  Note that doing so would require targets
204    // to notice uses in operands (due to constant exprs etc).  This should
205    // happen with the MC stuff eventually.
206    SwitchToDataSection("");
207
208    // Print out module-level global variables here.
209    for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
210         I != E; ++I) {
211      if (I->hasExternalWeakLinkage())
212        O << TAI->getWeakRefDirective() << Mang->getValueName(I) << '\n';
213    }
214
215    for (Module::const_iterator I = M.begin(), E = M.end();
216         I != E; ++I) {
217      if (I->hasExternalWeakLinkage())
218        O << TAI->getWeakRefDirective() << Mang->getValueName(I) << '\n';
219    }
220  }
221
222  if (TAI->getSetDirective()) {
223    if (!M.alias_empty())
224      SwitchToSection(TAI->getTextSection());
225
226    O << '\n';
227    for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
228         I != E; ++I) {
229      std::string Name = Mang->getValueName(I);
230      std::string Target;
231
232      const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
233      Target = Mang->getValueName(GV);
234
235      if (I->hasExternalLinkage() || !TAI->getWeakRefDirective())
236        O << "\t.globl\t" << Name << '\n';
237      else if (I->hasWeakLinkage())
238        O << TAI->getWeakRefDirective() << Name << '\n';
239      else if (!I->hasLocalLinkage())
240        assert(0 && "Invalid alias linkage");
241
242      printVisibility(Name, I->getVisibility());
243
244      O << TAI->getSetDirective() << ' ' << Name << ", " << Target << '\n';
245    }
246  }
247
248  GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
249  assert(MI && "AsmPrinter didn't require GCModuleInfo?");
250  for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
251    if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
252      MP->finishAssembly(O, *this, *TAI);
253
254  // If we don't have any trampolines, then we don't require stack memory
255  // to be executable. Some targets have a directive to declare this.
256  Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
257  if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
258    if (TAI->getNonexecutableStackDirective())
259      O << TAI->getNonexecutableStackDirective() << '\n';
260
261  delete Mang; Mang = 0;
262  DW = 0; MMI = 0;
263  return false;
264}
265
266const std::string &
267AsmPrinter::getCurrentFunctionEHName(const MachineFunction *MF,
268                                     std::string &Name) const {
269  assert(MF && "No machine function?");
270  Name = MF->getFunction()->getName();
271  if (Name.empty())
272    Name = Mang->getValueName(MF->getFunction());
273  Name = Mang->makeNameProper(TAI->getEHGlobalPrefix() +
274                              Name + ".eh", TAI->getGlobalPrefix());
275  return Name;
276}
277
278void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
279  // What's my mangled name?
280  CurrentFnName = Mang->getValueName(MF.getFunction());
281  IncrementFunctionNumber();
282}
283
284namespace {
285  // SectionCPs - Keep track the alignment, constpool entries per Section.
286  struct SectionCPs {
287    const Section *S;
288    unsigned Alignment;
289    SmallVector<unsigned, 4> CPEs;
290    SectionCPs(const Section *s, unsigned a) : S(s), Alignment(a) {};
291  };
292}
293
294/// EmitConstantPool - Print to the current output stream assembly
295/// representations of the constants in the constant pool MCP. This is
296/// used to print out constants which have been "spilled to memory" by
297/// the code generator.
298///
299void AsmPrinter::EmitConstantPool(MachineConstantPool *MCP) {
300  const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
301  if (CP.empty()) return;
302
303  // Calculate sections for constant pool entries. We collect entries to go into
304  // the same section together to reduce amount of section switch statements.
305  SmallVector<SectionCPs, 4> CPSections;
306  for (unsigned i = 0, e = CP.size(); i != e; ++i) {
307    MachineConstantPoolEntry CPE = CP[i];
308    unsigned Align = CPE.getAlignment();
309    const Section* S = TAI->SelectSectionForMachineConst(CPE.getType());
310    // The number of sections are small, just do a linear search from the
311    // last section to the first.
312    bool Found = false;
313    unsigned SecIdx = CPSections.size();
314    while (SecIdx != 0) {
315      if (CPSections[--SecIdx].S == S) {
316        Found = true;
317        break;
318      }
319    }
320    if (!Found) {
321      SecIdx = CPSections.size();
322      CPSections.push_back(SectionCPs(S, Align));
323    }
324
325    if (Align > CPSections[SecIdx].Alignment)
326      CPSections[SecIdx].Alignment = Align;
327    CPSections[SecIdx].CPEs.push_back(i);
328  }
329
330  // Now print stuff into the calculated sections.
331  for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
332    SwitchToSection(CPSections[i].S);
333    EmitAlignment(Log2_32(CPSections[i].Alignment));
334
335    unsigned Offset = 0;
336    for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
337      unsigned CPI = CPSections[i].CPEs[j];
338      MachineConstantPoolEntry CPE = CP[CPI];
339
340      // Emit inter-object padding for alignment.
341      unsigned AlignMask = CPE.getAlignment() - 1;
342      unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
343      EmitZeros(NewOffset - Offset);
344
345      const Type *Ty = CPE.getType();
346      Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
347
348      O << TAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << '_'
349        << CPI << ":\t\t\t\t\t";
350      if (VerboseAsm) {
351        O << TAI->getCommentString() << ' ';
352        WriteTypeSymbolic(O, CPE.getType(), 0);
353      }
354      O << '\n';
355      if (CPE.isMachineConstantPoolEntry())
356        EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
357      else
358        EmitGlobalConstant(CPE.Val.ConstVal);
359    }
360  }
361}
362
363/// EmitJumpTableInfo - Print assembly representations of the jump tables used
364/// by the current function to the current output stream.
365///
366void AsmPrinter::EmitJumpTableInfo(MachineJumpTableInfo *MJTI,
367                                   MachineFunction &MF) {
368  const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
369  if (JT.empty()) return;
370
371  bool IsPic = TM.getRelocationModel() == Reloc::PIC_;
372
373  // Pick the directive to use to print the jump table entries, and switch to
374  // the appropriate section.
375  TargetLowering *LoweringInfo = TM.getTargetLowering();
376
377  const char* JumpTableDataSection = TAI->getJumpTableDataSection();
378  const Function *F = MF.getFunction();
379  unsigned SectionFlags = TAI->SectionFlagsForGlobal(F);
380  bool JTInDiffSection = false;
381  if ((IsPic && !(LoweringInfo && LoweringInfo->usesGlobalOffsetTable())) ||
382      !JumpTableDataSection ||
383      SectionFlags & SectionFlags::Linkonce) {
384    // In PIC mode, we need to emit the jump table to the same section as the
385    // function body itself, otherwise the label differences won't make sense.
386    // We should also do if the section name is NULL or function is declared in
387    // discardable section.
388    SwitchToSection(TAI->SectionForGlobal(F));
389  } else {
390    SwitchToDataSection(JumpTableDataSection);
391    JTInDiffSection = true;
392  }
393
394  EmitAlignment(Log2_32(MJTI->getAlignment()));
395
396  for (unsigned i = 0, e = JT.size(); i != e; ++i) {
397    const std::vector<MachineBasicBlock*> &JTBBs = JT[i].MBBs;
398
399    // If this jump table was deleted, ignore it.
400    if (JTBBs.empty()) continue;
401
402    // For PIC codegen, if possible we want to use the SetDirective to reduce
403    // the number of relocations the assembler will generate for the jump table.
404    // Set directives are all printed before the jump table itself.
405    SmallPtrSet<MachineBasicBlock*, 16> EmittedSets;
406    if (TAI->getSetDirective() && IsPic)
407      for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
408        if (EmittedSets.insert(JTBBs[ii]))
409          printPICJumpTableSetLabel(i, JTBBs[ii]);
410
411    // On some targets (e.g. darwin) we want to emit two consequtive labels
412    // before each jump table.  The first label is never referenced, but tells
413    // the assembler and linker the extents of the jump table object.  The
414    // second label is actually referenced by the code.
415    if (JTInDiffSection) {
416      if (const char *JTLabelPrefix = TAI->getJumpTableSpecialLabelPrefix())
417        O << JTLabelPrefix << "JTI" << getFunctionNumber() << '_' << i << ":\n";
418    }
419
420    O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
421      << '_' << i << ":\n";
422
423    for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
424      printPICJumpTableEntry(MJTI, JTBBs[ii], i);
425      O << '\n';
426    }
427  }
428}
429
430void AsmPrinter::printPICJumpTableEntry(const MachineJumpTableInfo *MJTI,
431                                        const MachineBasicBlock *MBB,
432                                        unsigned uid)  const {
433  bool IsPic = TM.getRelocationModel() == Reloc::PIC_;
434
435  // Use JumpTableDirective otherwise honor the entry size from the jump table
436  // info.
437  const char *JTEntryDirective = TAI->getJumpTableDirective();
438  bool HadJTEntryDirective = JTEntryDirective != NULL;
439  if (!HadJTEntryDirective) {
440    JTEntryDirective = MJTI->getEntrySize() == 4 ?
441      TAI->getData32bitsDirective() : TAI->getData64bitsDirective();
442  }
443
444  O << JTEntryDirective << ' ';
445
446  // If we have emitted set directives for the jump table entries, print
447  // them rather than the entries themselves.  If we're emitting PIC, then
448  // emit the table entries as differences between two text section labels.
449  // If we're emitting non-PIC code, then emit the entries as direct
450  // references to the target basic blocks.
451  if (IsPic) {
452    if (TAI->getSetDirective()) {
453      O << TAI->getPrivateGlobalPrefix() << getFunctionNumber()
454        << '_' << uid << "_set_" << MBB->getNumber();
455    } else {
456      printBasicBlockLabel(MBB, false, false, false);
457      // If the arch uses custom Jump Table directives, don't calc relative to
458      // JT
459      if (!HadJTEntryDirective)
460        O << '-' << TAI->getPrivateGlobalPrefix() << "JTI"
461          << getFunctionNumber() << '_' << uid;
462    }
463  } else {
464    printBasicBlockLabel(MBB, false, false, false);
465  }
466}
467
468
469/// EmitSpecialLLVMGlobal - Check to see if the specified global is a
470/// special global used by LLVM.  If so, emit it and return true, otherwise
471/// do nothing and return false.
472bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
473  if (GV->getName() == "llvm.used") {
474    if (TAI->getUsedDirective() != 0)    // No need to emit this at all.
475      EmitLLVMUsedList(GV->getInitializer());
476    return true;
477  }
478
479  // Ignore debug and non-emitted data.
480  if (GV->getSection() == "llvm.metadata" ||
481      GV->hasAvailableExternallyLinkage())
482    return true;
483
484  if (!GV->hasAppendingLinkage()) return false;
485
486  assert(GV->hasInitializer() && "Not a special LLVM global!");
487
488  const TargetData *TD = TM.getTargetData();
489  unsigned Align = Log2_32(TD->getPointerPrefAlignment());
490  if (GV->getName() == "llvm.global_ctors") {
491    SwitchToDataSection(TAI->getStaticCtorsSection());
492    EmitAlignment(Align, 0);
493    EmitXXStructorList(GV->getInitializer());
494    return true;
495  }
496
497  if (GV->getName() == "llvm.global_dtors") {
498    SwitchToDataSection(TAI->getStaticDtorsSection());
499    EmitAlignment(Align, 0);
500    EmitXXStructorList(GV->getInitializer());
501    return true;
502  }
503
504  return false;
505}
506
507/// findGlobalValue - if CV is an expression equivalent to a single
508/// global value, return that value.
509const GlobalValue * AsmPrinter::findGlobalValue(const Constant *CV) {
510  if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
511    return GV;
512  else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
513    const TargetData *TD = TM.getTargetData();
514    unsigned Opcode = CE->getOpcode();
515    switch (Opcode) {
516    case Instruction::GetElementPtr: {
517      const Constant *ptrVal = CE->getOperand(0);
518      SmallVector<Value*, 8> idxVec(CE->op_begin()+1, CE->op_end());
519      if (TD->getIndexedOffset(ptrVal->getType(), &idxVec[0], idxVec.size()))
520        return 0;
521      return findGlobalValue(ptrVal);
522    }
523    case Instruction::BitCast:
524      return findGlobalValue(CE->getOperand(0));
525    default:
526      return 0;
527    }
528  }
529  return 0;
530}
531
532/// EmitLLVMUsedList - For targets that define a TAI::UsedDirective, mark each
533/// global in the specified llvm.used list for which emitUsedDirectiveFor
534/// is true, as being used with this directive.
535
536void AsmPrinter::EmitLLVMUsedList(Constant *List) {
537  const char *Directive = TAI->getUsedDirective();
538
539  // Should be an array of 'i8*'.
540  ConstantArray *InitList = dyn_cast<ConstantArray>(List);
541  if (InitList == 0) return;
542
543  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
544    const GlobalValue *GV = findGlobalValue(InitList->getOperand(i));
545    if (TAI->emitUsedDirectiveFor(GV, Mang)) {
546      O << Directive;
547      EmitConstantValueOnly(InitList->getOperand(i));
548      O << '\n';
549    }
550  }
551}
552
553/// EmitXXStructorList - Emit the ctor or dtor list.  This just prints out the
554/// function pointers, ignoring the init priority.
555void AsmPrinter::EmitXXStructorList(Constant *List) {
556  // Should be an array of '{ int, void ()* }' structs.  The first value is the
557  // init priority, which we ignore.
558  if (!isa<ConstantArray>(List)) return;
559  ConstantArray *InitList = cast<ConstantArray>(List);
560  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
561    if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
562      if (CS->getNumOperands() != 2) return;  // Not array of 2-element structs.
563
564      if (CS->getOperand(1)->isNullValue())
565        return;  // Found a null terminator, exit printing.
566      // Emit the function pointer.
567      EmitGlobalConstant(CS->getOperand(1));
568    }
569}
570
571/// getGlobalLinkName - Returns the asm/link name of of the specified
572/// global variable.  Should be overridden by each target asm printer to
573/// generate the appropriate value.
574const std::string &AsmPrinter::getGlobalLinkName(const GlobalVariable *GV,
575                                                 std::string &LinkName) const {
576  if (isa<Function>(GV)) {
577    LinkName += TAI->getFunctionAddrPrefix();
578    LinkName += Mang->getValueName(GV);
579    LinkName += TAI->getFunctionAddrSuffix();
580  } else {
581    LinkName += TAI->getGlobalVarAddrPrefix();
582    LinkName += Mang->getValueName(GV);
583    LinkName += TAI->getGlobalVarAddrSuffix();
584  }
585
586  return LinkName;
587}
588
589/// EmitExternalGlobal - Emit the external reference to a global variable.
590/// Should be overridden if an indirect reference should be used.
591void AsmPrinter::EmitExternalGlobal(const GlobalVariable *GV) {
592  std::string GLN;
593  O << getGlobalLinkName(GV, GLN);
594}
595
596
597
598//===----------------------------------------------------------------------===//
599/// LEB 128 number encoding.
600
601/// PrintULEB128 - Print a series of hexidecimal values (separated by commas)
602/// representing an unsigned leb128 value.
603void AsmPrinter::PrintULEB128(unsigned Value) const {
604  char Buffer[20];
605  do {
606    unsigned char Byte = static_cast<unsigned char>(Value & 0x7f);
607    Value >>= 7;
608    if (Value) Byte |= 0x80;
609    O << "0x" << utohex_buffer(Byte, Buffer+20);
610    if (Value) O << ", ";
611  } while (Value);
612}
613
614/// PrintSLEB128 - Print a series of hexidecimal values (separated by commas)
615/// representing a signed leb128 value.
616void AsmPrinter::PrintSLEB128(int Value) const {
617  int Sign = Value >> (8 * sizeof(Value) - 1);
618  bool IsMore;
619  char Buffer[20];
620
621  do {
622    unsigned char Byte = static_cast<unsigned char>(Value & 0x7f);
623    Value >>= 7;
624    IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0;
625    if (IsMore) Byte |= 0x80;
626    O << "0x" << utohex_buffer(Byte, Buffer+20);
627    if (IsMore) O << ", ";
628  } while (IsMore);
629}
630
631//===--------------------------------------------------------------------===//
632// Emission and print routines
633//
634
635/// PrintHex - Print a value as a hexidecimal value.
636///
637void AsmPrinter::PrintHex(int Value) const {
638  char Buffer[20];
639  O << "0x" << utohex_buffer(static_cast<unsigned>(Value), Buffer+20);
640}
641
642/// EOL - Print a newline character to asm stream.  If a comment is present
643/// then it will be printed first.  Comments should not contain '\n'.
644void AsmPrinter::EOL() const {
645  O << '\n';
646}
647
648void AsmPrinter::EOL(const std::string &Comment) const {
649  if (VerboseAsm && !Comment.empty()) {
650    O << '\t'
651      << TAI->getCommentString()
652      << ' '
653      << Comment;
654  }
655  O << '\n';
656}
657
658void AsmPrinter::EOL(const char* Comment) const {
659  if (VerboseAsm && *Comment) {
660    O << '\t'
661      << TAI->getCommentString()
662      << ' '
663      << Comment;
664  }
665  O << '\n';
666}
667
668/// EmitULEB128Bytes - Emit an assembler byte data directive to compose an
669/// unsigned leb128 value.
670void AsmPrinter::EmitULEB128Bytes(unsigned Value) const {
671  if (TAI->hasLEB128()) {
672    O << "\t.uleb128\t"
673      << Value;
674  } else {
675    O << TAI->getData8bitsDirective();
676    PrintULEB128(Value);
677  }
678}
679
680/// EmitSLEB128Bytes - print an assembler byte data directive to compose a
681/// signed leb128 value.
682void AsmPrinter::EmitSLEB128Bytes(int Value) const {
683  if (TAI->hasLEB128()) {
684    O << "\t.sleb128\t"
685      << Value;
686  } else {
687    O << TAI->getData8bitsDirective();
688    PrintSLEB128(Value);
689  }
690}
691
692/// EmitInt8 - Emit a byte directive and value.
693///
694void AsmPrinter::EmitInt8(int Value) const {
695  O << TAI->getData8bitsDirective();
696  PrintHex(Value & 0xFF);
697}
698
699/// EmitInt16 - Emit a short directive and value.
700///
701void AsmPrinter::EmitInt16(int Value) const {
702  O << TAI->getData16bitsDirective();
703  PrintHex(Value & 0xFFFF);
704}
705
706/// EmitInt32 - Emit a long directive and value.
707///
708void AsmPrinter::EmitInt32(int Value) const {
709  O << TAI->getData32bitsDirective();
710  PrintHex(Value);
711}
712
713/// EmitInt64 - Emit a long long directive and value.
714///
715void AsmPrinter::EmitInt64(uint64_t Value) const {
716  if (TAI->getData64bitsDirective()) {
717    O << TAI->getData64bitsDirective();
718    PrintHex(Value);
719  } else {
720    if (TM.getTargetData()->isBigEndian()) {
721      EmitInt32(unsigned(Value >> 32)); O << '\n';
722      EmitInt32(unsigned(Value));
723    } else {
724      EmitInt32(unsigned(Value)); O << '\n';
725      EmitInt32(unsigned(Value >> 32));
726    }
727  }
728}
729
730/// toOctal - Convert the low order bits of X into an octal digit.
731///
732static inline char toOctal(int X) {
733  return (X&7)+'0';
734}
735
736/// printStringChar - Print a char, escaped if necessary.
737///
738static void printStringChar(raw_ostream &O, unsigned char C) {
739  if (C == '"') {
740    O << "\\\"";
741  } else if (C == '\\') {
742    O << "\\\\";
743  } else if (isprint((unsigned char)C)) {
744    O << C;
745  } else {
746    switch(C) {
747    case '\b': O << "\\b"; break;
748    case '\f': O << "\\f"; break;
749    case '\n': O << "\\n"; break;
750    case '\r': O << "\\r"; break;
751    case '\t': O << "\\t"; break;
752    default:
753      O << '\\';
754      O << toOctal(C >> 6);
755      O << toOctal(C >> 3);
756      O << toOctal(C >> 0);
757      break;
758    }
759  }
760}
761
762/// EmitString - Emit a string with quotes and a null terminator.
763/// Special characters are emitted properly.
764/// \literal (Eg. '\t') \endliteral
765void AsmPrinter::EmitString(const std::string &String) const {
766  EmitString(String.c_str(), String.size());
767}
768
769void AsmPrinter::EmitString(const char *String, unsigned Size) const {
770  const char* AscizDirective = TAI->getAscizDirective();
771  if (AscizDirective)
772    O << AscizDirective;
773  else
774    O << TAI->getAsciiDirective();
775  O << '\"';
776  for (unsigned i = 0; i < Size; ++i)
777    printStringChar(O, String[i]);
778  if (AscizDirective)
779    O << '\"';
780  else
781    O << "\\0\"";
782}
783
784
785/// EmitFile - Emit a .file directive.
786void AsmPrinter::EmitFile(unsigned Number, const std::string &Name) const {
787  O << "\t.file\t" << Number << " \"";
788  for (unsigned i = 0, N = Name.size(); i < N; ++i)
789    printStringChar(O, Name[i]);
790  O << '\"';
791}
792
793
794//===----------------------------------------------------------------------===//
795
796// EmitAlignment - Emit an alignment directive to the specified power of
797// two boundary.  For example, if you pass in 3 here, you will get an 8
798// byte alignment.  If a global value is specified, and if that global has
799// an explicit alignment requested, it will unconditionally override the
800// alignment request.  However, if ForcedAlignBits is specified, this value
801// has final say: the ultimate alignment will be the max of ForcedAlignBits
802// and the alignment computed with NumBits and the global.
803//
804// The algorithm is:
805//     Align = NumBits;
806//     if (GV && GV->hasalignment) Align = GV->getalignment();
807//     Align = std::max(Align, ForcedAlignBits);
808//
809void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
810                               unsigned ForcedAlignBits,
811                               bool UseFillExpr) const {
812  if (GV && GV->getAlignment())
813    NumBits = Log2_32(GV->getAlignment());
814  NumBits = std::max(NumBits, ForcedAlignBits);
815
816  if (NumBits == 0) return;   // No need to emit alignment.
817  if (TAI->getAlignmentIsInBytes()) NumBits = 1 << NumBits;
818  O << TAI->getAlignDirective() << NumBits;
819
820  unsigned FillValue = TAI->getTextAlignFillValue();
821  UseFillExpr &= IsInTextSection && FillValue;
822  if (UseFillExpr) {
823    O << ',';
824    PrintHex(FillValue);
825  }
826  O << '\n';
827}
828
829
830/// EmitZeros - Emit a block of zeros.
831///
832void AsmPrinter::EmitZeros(uint64_t NumZeros, unsigned AddrSpace) const {
833  if (NumZeros) {
834    if (TAI->getZeroDirective()) {
835      O << TAI->getZeroDirective() << NumZeros;
836      if (TAI->getZeroDirectiveSuffix())
837        O << TAI->getZeroDirectiveSuffix();
838      O << '\n';
839    } else {
840      for (; NumZeros; --NumZeros)
841        O << TAI->getData8bitsDirective(AddrSpace) << "0\n";
842    }
843  }
844}
845
846// Print out the specified constant, without a storage class.  Only the
847// constants valid in constant expressions can occur here.
848void AsmPrinter::EmitConstantValueOnly(const Constant *CV) {
849  if (CV->isNullValue() || isa<UndefValue>(CV))
850    O << '0';
851  else if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
852    O << CI->getZExtValue();
853  } else if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV)) {
854    // This is a constant address for a global variable or function. Use the
855    // name of the variable or function as the address value, possibly
856    // decorating it with GlobalVarAddrPrefix/Suffix or
857    // FunctionAddrPrefix/Suffix (these all default to "" )
858    if (isa<Function>(GV)) {
859      O << TAI->getFunctionAddrPrefix()
860        << Mang->getValueName(GV)
861        << TAI->getFunctionAddrSuffix();
862    } else {
863      O << TAI->getGlobalVarAddrPrefix()
864        << Mang->getValueName(GV)
865        << TAI->getGlobalVarAddrSuffix();
866    }
867  } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
868    const TargetData *TD = TM.getTargetData();
869    unsigned Opcode = CE->getOpcode();
870    switch (Opcode) {
871    case Instruction::GetElementPtr: {
872      // generate a symbolic expression for the byte address
873      const Constant *ptrVal = CE->getOperand(0);
874      SmallVector<Value*, 8> idxVec(CE->op_begin()+1, CE->op_end());
875      if (int64_t Offset = TD->getIndexedOffset(ptrVal->getType(), &idxVec[0],
876                                                idxVec.size())) {
877        // Truncate/sext the offset to the pointer size.
878        if (TD->getPointerSizeInBits() != 64) {
879          int SExtAmount = 64-TD->getPointerSizeInBits();
880          Offset = (Offset << SExtAmount) >> SExtAmount;
881        }
882
883        if (Offset)
884          O << '(';
885        EmitConstantValueOnly(ptrVal);
886        if (Offset > 0)
887          O << ") + " << Offset;
888        else if (Offset < 0)
889          O << ") - " << -Offset;
890      } else {
891        EmitConstantValueOnly(ptrVal);
892      }
893      break;
894    }
895    case Instruction::Trunc:
896    case Instruction::ZExt:
897    case Instruction::SExt:
898    case Instruction::FPTrunc:
899    case Instruction::FPExt:
900    case Instruction::UIToFP:
901    case Instruction::SIToFP:
902    case Instruction::FPToUI:
903    case Instruction::FPToSI:
904      assert(0 && "FIXME: Don't yet support this kind of constant cast expr");
905      break;
906    case Instruction::BitCast:
907      return EmitConstantValueOnly(CE->getOperand(0));
908
909    case Instruction::IntToPtr: {
910      // Handle casts to pointers by changing them into casts to the appropriate
911      // integer type.  This promotes constant folding and simplifies this code.
912      Constant *Op = CE->getOperand(0);
913      Op = ConstantExpr::getIntegerCast(Op, TD->getIntPtrType(), false/*ZExt*/);
914      return EmitConstantValueOnly(Op);
915    }
916
917
918    case Instruction::PtrToInt: {
919      // Support only foldable casts to/from pointers that can be eliminated by
920      // changing the pointer to the appropriately sized integer type.
921      Constant *Op = CE->getOperand(0);
922      const Type *Ty = CE->getType();
923
924      // We can emit the pointer value into this slot if the slot is an
925      // integer slot greater or equal to the size of the pointer.
926      if (TD->getTypeAllocSize(Ty) >= TD->getTypeAllocSize(Op->getType()))
927        return EmitConstantValueOnly(Op);
928
929      O << "((";
930      EmitConstantValueOnly(Op);
931      APInt ptrMask = APInt::getAllOnesValue(TD->getTypeAllocSizeInBits(Ty));
932
933      SmallString<40> S;
934      ptrMask.toStringUnsigned(S);
935      O << ") & " << S.c_str() << ')';
936      break;
937    }
938    case Instruction::Add:
939    case Instruction::Sub:
940    case Instruction::And:
941    case Instruction::Or:
942    case Instruction::Xor:
943      O << '(';
944      EmitConstantValueOnly(CE->getOperand(0));
945      O << ')';
946      switch (Opcode) {
947      case Instruction::Add:
948       O << " + ";
949       break;
950      case Instruction::Sub:
951       O << " - ";
952       break;
953      case Instruction::And:
954       O << " & ";
955       break;
956      case Instruction::Or:
957       O << " | ";
958       break;
959      case Instruction::Xor:
960       O << " ^ ";
961       break;
962      default:
963       break;
964      }
965      O << '(';
966      EmitConstantValueOnly(CE->getOperand(1));
967      O << ')';
968      break;
969    default:
970      assert(0 && "Unsupported operator!");
971    }
972  } else {
973    assert(0 && "Unknown constant value!");
974  }
975}
976
977/// printAsCString - Print the specified array as a C compatible string, only if
978/// the predicate isString is true.
979///
980static void printAsCString(raw_ostream &O, const ConstantArray *CVA,
981                           unsigned LastElt) {
982  assert(CVA->isString() && "Array is not string compatible!");
983
984  O << '\"';
985  for (unsigned i = 0; i != LastElt; ++i) {
986    unsigned char C =
987        (unsigned char)cast<ConstantInt>(CVA->getOperand(i))->getZExtValue();
988    printStringChar(O, C);
989  }
990  O << '\"';
991}
992
993/// EmitString - Emit a zero-byte-terminated string constant.
994///
995void AsmPrinter::EmitString(const ConstantArray *CVA) const {
996  unsigned NumElts = CVA->getNumOperands();
997  if (TAI->getAscizDirective() && NumElts &&
998      cast<ConstantInt>(CVA->getOperand(NumElts-1))->getZExtValue() == 0) {
999    O << TAI->getAscizDirective();
1000    printAsCString(O, CVA, NumElts-1);
1001  } else {
1002    O << TAI->getAsciiDirective();
1003    printAsCString(O, CVA, NumElts);
1004  }
1005  O << '\n';
1006}
1007
1008void AsmPrinter::EmitGlobalConstantArray(const ConstantArray *CVA,
1009                                         unsigned AddrSpace) {
1010  if (CVA->isString()) {
1011    EmitString(CVA);
1012  } else { // Not a string.  Print the values in successive locations
1013    for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i)
1014      EmitGlobalConstant(CVA->getOperand(i), AddrSpace);
1015  }
1016}
1017
1018void AsmPrinter::EmitGlobalConstantVector(const ConstantVector *CP) {
1019  const VectorType *PTy = CP->getType();
1020
1021  for (unsigned I = 0, E = PTy->getNumElements(); I < E; ++I)
1022    EmitGlobalConstant(CP->getOperand(I));
1023}
1024
1025void AsmPrinter::EmitGlobalConstantStruct(const ConstantStruct *CVS,
1026                                          unsigned AddrSpace) {
1027  // Print the fields in successive locations. Pad to align if needed!
1028  const TargetData *TD = TM.getTargetData();
1029  unsigned Size = TD->getTypeAllocSize(CVS->getType());
1030  const StructLayout *cvsLayout = TD->getStructLayout(CVS->getType());
1031  uint64_t sizeSoFar = 0;
1032  for (unsigned i = 0, e = CVS->getNumOperands(); i != e; ++i) {
1033    const Constant* field = CVS->getOperand(i);
1034
1035    // Check if padding is needed and insert one or more 0s.
1036    uint64_t fieldSize = TD->getTypeAllocSize(field->getType());
1037    uint64_t padSize = ((i == e-1 ? Size : cvsLayout->getElementOffset(i+1))
1038                        - cvsLayout->getElementOffset(i)) - fieldSize;
1039    sizeSoFar += fieldSize + padSize;
1040
1041    // Now print the actual field value.
1042    EmitGlobalConstant(field, AddrSpace);
1043
1044    // Insert padding - this may include padding to increase the size of the
1045    // current field up to the ABI size (if the struct is not packed) as well
1046    // as padding to ensure that the next field starts at the right offset.
1047    EmitZeros(padSize, AddrSpace);
1048  }
1049  assert(sizeSoFar == cvsLayout->getSizeInBytes() &&
1050         "Layout of constant struct may be incorrect!");
1051}
1052
1053void AsmPrinter::EmitGlobalConstantFP(const ConstantFP *CFP,
1054                                      unsigned AddrSpace) {
1055  // FP Constants are printed as integer constants to avoid losing
1056  // precision...
1057  const TargetData *TD = TM.getTargetData();
1058  if (CFP->getType() == Type::DoubleTy) {
1059    double Val = CFP->getValueAPF().convertToDouble();  // for comment only
1060    uint64_t i = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1061    if (TAI->getData64bitsDirective(AddrSpace)) {
1062      O << TAI->getData64bitsDirective(AddrSpace) << i;
1063      if (VerboseAsm)
1064        O << '\t' << TAI->getCommentString() << " double value: " << Val;
1065      O << '\n';
1066    } else if (TD->isBigEndian()) {
1067      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i >> 32);
1068      if (VerboseAsm)
1069        O << '\t' << TAI->getCommentString()
1070          << " double most significant word " << Val;
1071      O << '\n';
1072      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i);
1073      if (VerboseAsm)
1074        O << '\t' << TAI->getCommentString()
1075          << " double least significant word " << Val;
1076      O << '\n';
1077    } else {
1078      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i);
1079      if (VerboseAsm)
1080        O << '\t' << TAI->getCommentString()
1081          << " double least significant word " << Val;
1082      O << '\n';
1083      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(i >> 32);
1084      if (VerboseAsm)
1085        O << '\t' << TAI->getCommentString()
1086          << " double most significant word " << Val;
1087      O << '\n';
1088    }
1089    return;
1090  } else if (CFP->getType() == Type::FloatTy) {
1091    float Val = CFP->getValueAPF().convertToFloat();  // for comment only
1092    O << TAI->getData32bitsDirective(AddrSpace)
1093      << CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1094    if (VerboseAsm)
1095      O << '\t' << TAI->getCommentString() << " float " << Val;
1096    O << '\n';
1097    return;
1098  } else if (CFP->getType() == Type::X86_FP80Ty) {
1099    // all long double variants are printed as hex
1100    // api needed to prevent premature destruction
1101    APInt api = CFP->getValueAPF().bitcastToAPInt();
1102    const uint64_t *p = api.getRawData();
1103    // Convert to double so we can print the approximate val as a comment.
1104    APFloat DoubleVal = CFP->getValueAPF();
1105    bool ignored;
1106    DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1107                      &ignored);
1108    if (TD->isBigEndian()) {
1109      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[1]);
1110      if (VerboseAsm)
1111        O << '\t' << TAI->getCommentString()
1112          << " long double most significant halfword of ~"
1113          << DoubleVal.convertToDouble();
1114      O << '\n';
1115      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 48);
1116      if (VerboseAsm)
1117        O << '\t' << TAI->getCommentString() << " long double next halfword";
1118      O << '\n';
1119      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 32);
1120      if (VerboseAsm)
1121        O << '\t' << TAI->getCommentString() << " long double next halfword";
1122      O << '\n';
1123      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 16);
1124      if (VerboseAsm)
1125        O << '\t' << TAI->getCommentString() << " long double next halfword";
1126      O << '\n';
1127      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0]);
1128      if (VerboseAsm)
1129        O << '\t' << TAI->getCommentString()
1130          << " long double least significant halfword";
1131      O << '\n';
1132     } else {
1133      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0]);
1134      if (VerboseAsm)
1135        O << '\t' << TAI->getCommentString()
1136          << " long double least significant halfword of ~"
1137          << DoubleVal.convertToDouble();
1138      O << '\n';
1139      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 16);
1140      if (VerboseAsm)
1141        O << '\t' << TAI->getCommentString()
1142          << " long double next halfword";
1143      O << '\n';
1144      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 32);
1145      if (VerboseAsm)
1146        O << '\t' << TAI->getCommentString()
1147          << " long double next halfword";
1148      O << '\n';
1149      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[0] >> 48);
1150      if (VerboseAsm)
1151        O << '\t' << TAI->getCommentString()
1152          << " long double next halfword";
1153      O << '\n';
1154      O << TAI->getData16bitsDirective(AddrSpace) << uint16_t(p[1]);
1155      if (VerboseAsm)
1156        O << '\t' << TAI->getCommentString()
1157          << " long double most significant halfword";
1158      O << '\n';
1159    }
1160    EmitZeros(TD->getTypeAllocSize(Type::X86_FP80Ty) -
1161              TD->getTypeStoreSize(Type::X86_FP80Ty), AddrSpace);
1162    return;
1163  } else if (CFP->getType() == Type::PPC_FP128Ty) {
1164    // all long double variants are printed as hex
1165    // api needed to prevent premature destruction
1166    APInt api = CFP->getValueAPF().bitcastToAPInt();
1167    const uint64_t *p = api.getRawData();
1168    if (TD->isBigEndian()) {
1169      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0] >> 32);
1170      if (VerboseAsm)
1171        O << '\t' << TAI->getCommentString()
1172          << " long double most significant word";
1173      O << '\n';
1174      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0]);
1175      if (VerboseAsm)
1176        O << '\t' << TAI->getCommentString()
1177        << " long double next word";
1178      O << '\n';
1179      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1] >> 32);
1180      if (VerboseAsm)
1181        O << '\t' << TAI->getCommentString()
1182          << " long double next word";
1183      O << '\n';
1184      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1]);
1185      if (VerboseAsm)
1186        O << '\t' << TAI->getCommentString()
1187          << " long double least significant word";
1188      O << '\n';
1189     } else {
1190      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1]);
1191      if (VerboseAsm)
1192        O << '\t' << TAI->getCommentString()
1193          << " long double least significant word";
1194      O << '\n';
1195      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[1] >> 32);
1196      if (VerboseAsm)
1197        O << '\t' << TAI->getCommentString()
1198          << " long double next word";
1199      O << '\n';
1200      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0]);
1201      if (VerboseAsm)
1202        O << '\t' << TAI->getCommentString()
1203          << " long double next word";
1204      O << '\n';
1205      O << TAI->getData32bitsDirective(AddrSpace) << uint32_t(p[0] >> 32);
1206      if (VerboseAsm)
1207        O << '\t' << TAI->getCommentString()
1208          << " long double most significant word";
1209      O << '\n';
1210    }
1211    return;
1212  } else assert(0 && "Floating point constant type not handled");
1213}
1214
1215void AsmPrinter::EmitGlobalConstantLargeInt(const ConstantInt *CI,
1216                                            unsigned AddrSpace) {
1217  const TargetData *TD = TM.getTargetData();
1218  unsigned BitWidth = CI->getBitWidth();
1219  assert(isPowerOf2_32(BitWidth) &&
1220         "Non-power-of-2-sized integers not handled!");
1221
1222  // We don't expect assemblers to support integer data directives
1223  // for more than 64 bits, so we emit the data in at most 64-bit
1224  // quantities at a time.
1225  const uint64_t *RawData = CI->getValue().getRawData();
1226  for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1227    uint64_t Val;
1228    if (TD->isBigEndian())
1229      Val = RawData[e - i - 1];
1230    else
1231      Val = RawData[i];
1232
1233    if (TAI->getData64bitsDirective(AddrSpace))
1234      O << TAI->getData64bitsDirective(AddrSpace) << Val << '\n';
1235    else if (TD->isBigEndian()) {
1236      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val >> 32);
1237      if (VerboseAsm)
1238        O << '\t' << TAI->getCommentString()
1239          << " Double-word most significant word " << Val;
1240      O << '\n';
1241      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val);
1242      if (VerboseAsm)
1243        O << '\t' << TAI->getCommentString()
1244          << " Double-word least significant word " << Val;
1245      O << '\n';
1246    } else {
1247      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val);
1248      if (VerboseAsm)
1249        O << '\t' << TAI->getCommentString()
1250          << " Double-word least significant word " << Val;
1251      O << '\n';
1252      O << TAI->getData32bitsDirective(AddrSpace) << unsigned(Val >> 32);
1253      if (VerboseAsm)
1254        O << '\t' << TAI->getCommentString()
1255          << " Double-word most significant word " << Val;
1256      O << '\n';
1257    }
1258  }
1259}
1260
1261/// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1262void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1263  const TargetData *TD = TM.getTargetData();
1264  const Type *type = CV->getType();
1265  unsigned Size = TD->getTypeAllocSize(type);
1266
1267  if (CV->isNullValue() || isa<UndefValue>(CV)) {
1268    EmitZeros(Size, AddrSpace);
1269    return;
1270  } else if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) {
1271    EmitGlobalConstantArray(CVA , AddrSpace);
1272    return;
1273  } else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) {
1274    EmitGlobalConstantStruct(CVS, AddrSpace);
1275    return;
1276  } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) {
1277    EmitGlobalConstantFP(CFP, AddrSpace);
1278    return;
1279  } else if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1280    // Small integers are handled below; large integers are handled here.
1281    if (Size > 4) {
1282      EmitGlobalConstantLargeInt(CI, AddrSpace);
1283      return;
1284    }
1285  } else if (const ConstantVector *CP = dyn_cast<ConstantVector>(CV)) {
1286    EmitGlobalConstantVector(CP);
1287    return;
1288  }
1289
1290  printDataDirective(type, AddrSpace);
1291  EmitConstantValueOnly(CV);
1292  if (VerboseAsm) {
1293    if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1294      SmallString<40> S;
1295      CI->getValue().toStringUnsigned(S, 16);
1296      O << "\t\t\t" << TAI->getCommentString() << " 0x" << S.c_str();
1297    }
1298  }
1299  O << '\n';
1300}
1301
1302void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1303  // Target doesn't support this yet!
1304  LLVM_UNREACHABLE("Target does not support EmitMachineConstantPoolValue");
1305}
1306
1307/// PrintSpecial - Print information related to the specified machine instr
1308/// that is independent of the operand, and may be independent of the instr
1309/// itself.  This can be useful for portably encoding the comment character
1310/// or other bits of target-specific knowledge into the asmstrings.  The
1311/// syntax used is ${:comment}.  Targets can override this to add support
1312/// for their own strange codes.
1313void AsmPrinter::PrintSpecial(const MachineInstr *MI, const char *Code) const {
1314  if (!strcmp(Code, "private")) {
1315    O << TAI->getPrivateGlobalPrefix();
1316  } else if (!strcmp(Code, "comment")) {
1317    if (VerboseAsm)
1318      O << TAI->getCommentString();
1319  } else if (!strcmp(Code, "uid")) {
1320    // Comparing the address of MI isn't sufficient, because machineinstrs may
1321    // be allocated to the same address across functions.
1322    const Function *ThisF = MI->getParent()->getParent()->getFunction();
1323
1324    // If this is a new LastFn instruction, bump the counter.
1325    if (LastMI != MI || LastFn != ThisF) {
1326      ++Counter;
1327      LastMI = MI;
1328      LastFn = ThisF;
1329    }
1330    O << Counter;
1331  } else {
1332    std::string msg;
1333    raw_string_ostream Msg(msg);
1334    Msg << "Unknown special formatter '" << Code
1335         << "' for machine instr: " << *MI;
1336    llvm_report_error(Msg.str());
1337  }
1338}
1339
1340/// processDebugLoc - Processes the debug information of each machine
1341/// instruction's DebugLoc.
1342void AsmPrinter::processDebugLoc(DebugLoc DL) {
1343  if (TAI->doesSupportDebugInformation() && DW->ShouldEmitDwarfDebug()) {
1344    if (!DL.isUnknown()) {
1345      DebugLocTuple CurDLT = MF->getDebugLocTuple(DL);
1346
1347      if (CurDLT.CompileUnit != 0 && PrevDLT != CurDLT)
1348        printLabel(DW->RecordSourceLine(CurDLT.Line, CurDLT.Col,
1349                                        DICompileUnit(CurDLT.CompileUnit)));
1350
1351      PrevDLT = CurDLT;
1352    }
1353  }
1354}
1355
1356/// printInlineAsm - This method formats and prints the specified machine
1357/// instruction that is an inline asm.
1358void AsmPrinter::printInlineAsm(const MachineInstr *MI) const {
1359  unsigned NumOperands = MI->getNumOperands();
1360
1361  // Count the number of register definitions.
1362  unsigned NumDefs = 0;
1363  for (; MI->getOperand(NumDefs).isReg() && MI->getOperand(NumDefs).isDef();
1364       ++NumDefs)
1365    assert(NumDefs != NumOperands-1 && "No asm string?");
1366
1367  assert(MI->getOperand(NumDefs).isSymbol() && "No asm string?");
1368
1369  // Disassemble the AsmStr, printing out the literal pieces, the operands, etc.
1370  const char *AsmStr = MI->getOperand(NumDefs).getSymbolName();
1371
1372  // If this asmstr is empty, just print the #APP/#NOAPP markers.
1373  // These are useful to see where empty asm's wound up.
1374  if (AsmStr[0] == 0) {
1375    O << TAI->getInlineAsmStart() << "\n\t" << TAI->getInlineAsmEnd() << '\n';
1376    return;
1377  }
1378
1379  O << TAI->getInlineAsmStart() << "\n\t";
1380
1381  // The variant of the current asmprinter.
1382  int AsmPrinterVariant = TAI->getAssemblerDialect();
1383
1384  int CurVariant = -1;            // The number of the {.|.|.} region we are in.
1385  const char *LastEmitted = AsmStr; // One past the last character emitted.
1386
1387  while (*LastEmitted) {
1388    switch (*LastEmitted) {
1389    default: {
1390      // Not a special case, emit the string section literally.
1391      const char *LiteralEnd = LastEmitted+1;
1392      while (*LiteralEnd && *LiteralEnd != '{' && *LiteralEnd != '|' &&
1393             *LiteralEnd != '}' && *LiteralEnd != '$' && *LiteralEnd != '\n')
1394        ++LiteralEnd;
1395      if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1396        O.write(LastEmitted, LiteralEnd-LastEmitted);
1397      LastEmitted = LiteralEnd;
1398      break;
1399    }
1400    case '\n':
1401      ++LastEmitted;   // Consume newline character.
1402      O << '\n';       // Indent code with newline.
1403      break;
1404    case '$': {
1405      ++LastEmitted;   // Consume '$' character.
1406      bool Done = true;
1407
1408      // Handle escapes.
1409      switch (*LastEmitted) {
1410      default: Done = false; break;
1411      case '$':     // $$ -> $
1412        if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
1413          O << '$';
1414        ++LastEmitted;  // Consume second '$' character.
1415        break;
1416      case '(':             // $( -> same as GCC's { character.
1417        ++LastEmitted;      // Consume '(' character.
1418        if (CurVariant != -1) {
1419          llvm_report_error("Nested variants found in inline asm string: '"
1420                            + std::string(AsmStr) + "'");
1421        }
1422        CurVariant = 0;     // We're in the first variant now.
1423        break;
1424      case '|':
1425        ++LastEmitted;  // consume '|' character.
1426        if (CurVariant == -1)
1427          O << '|';       // this is gcc's behavior for | outside a variant
1428        else
1429          ++CurVariant;   // We're in the next variant.
1430        break;
1431      case ')':         // $) -> same as GCC's } char.
1432        ++LastEmitted;  // consume ')' character.
1433        if (CurVariant == -1)
1434          O << '}';     // this is gcc's behavior for } outside a variant
1435        else
1436          CurVariant = -1;
1437        break;
1438      }
1439      if (Done) break;
1440
1441      bool HasCurlyBraces = false;
1442      if (*LastEmitted == '{') {     // ${variable}
1443        ++LastEmitted;               // Consume '{' character.
1444        HasCurlyBraces = true;
1445      }
1446
1447      // If we have ${:foo}, then this is not a real operand reference, it is a
1448      // "magic" string reference, just like in .td files.  Arrange to call
1449      // PrintSpecial.
1450      if (HasCurlyBraces && *LastEmitted == ':') {
1451        ++LastEmitted;
1452        const char *StrStart = LastEmitted;
1453        const char *StrEnd = strchr(StrStart, '}');
1454        if (StrEnd == 0) {
1455          llvm_report_error("Unterminated ${:foo} operand in inline asm string: '"
1456                            + std::string(AsmStr) + "'");
1457        }
1458
1459        std::string Val(StrStart, StrEnd);
1460        PrintSpecial(MI, Val.c_str());
1461        LastEmitted = StrEnd+1;
1462        break;
1463      }
1464
1465      const char *IDStart = LastEmitted;
1466      char *IDEnd;
1467      errno = 0;
1468      long Val = strtol(IDStart, &IDEnd, 10); // We only accept numbers for IDs.
1469      if (!isdigit(*IDStart) || (Val == 0 && errno == EINVAL)) {
1470        llvm_report_error("Bad $ operand number in inline asm string: '"
1471                          + std::string(AsmStr) + "'");
1472      }
1473      LastEmitted = IDEnd;
1474
1475      char Modifier[2] = { 0, 0 };
1476
1477      if (HasCurlyBraces) {
1478        // If we have curly braces, check for a modifier character.  This
1479        // supports syntax like ${0:u}, which correspond to "%u0" in GCC asm.
1480        if (*LastEmitted == ':') {
1481          ++LastEmitted;    // Consume ':' character.
1482          if (*LastEmitted == 0) {
1483            llvm_report_error("Bad ${:} expression in inline asm string: '"
1484                              + std::string(AsmStr) + "'");
1485          }
1486
1487          Modifier[0] = *LastEmitted;
1488          ++LastEmitted;    // Consume modifier character.
1489        }
1490
1491        if (*LastEmitted != '}') {
1492          llvm_report_error("Bad ${} expression in inline asm string: '"
1493                            + std::string(AsmStr) + "'");
1494        }
1495        ++LastEmitted;    // Consume '}' character.
1496      }
1497
1498      if ((unsigned)Val >= NumOperands-1) {
1499        llvm_report_error("Invalid $ operand number in inline asm string: '"
1500                          + std::string(AsmStr) + "'");
1501      }
1502
1503      // Okay, we finally have a value number.  Ask the target to print this
1504      // operand!
1505      if (CurVariant == -1 || CurVariant == AsmPrinterVariant) {
1506        unsigned OpNo = 1;
1507
1508        bool Error = false;
1509
1510        // Scan to find the machine operand number for the operand.
1511        for (; Val; --Val) {
1512          if (OpNo >= MI->getNumOperands()) break;
1513          unsigned OpFlags = MI->getOperand(OpNo).getImm();
1514          OpNo += InlineAsm::getNumOperandRegisters(OpFlags) + 1;
1515        }
1516
1517        if (OpNo >= MI->getNumOperands()) {
1518          Error = true;
1519        } else {
1520          unsigned OpFlags = MI->getOperand(OpNo).getImm();
1521          ++OpNo;  // Skip over the ID number.
1522
1523          if (Modifier[0]=='l')  // labels are target independent
1524            printBasicBlockLabel(MI->getOperand(OpNo).getMBB(),
1525                                 false, false, false);
1526          else {
1527            AsmPrinter *AP = const_cast<AsmPrinter*>(this);
1528            if ((OpFlags & 7) == 4) {
1529              Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant,
1530                                                Modifier[0] ? Modifier : 0);
1531            } else {
1532              Error = AP->PrintAsmOperand(MI, OpNo, AsmPrinterVariant,
1533                                          Modifier[0] ? Modifier : 0);
1534            }
1535          }
1536        }
1537        if (Error) {
1538          std::string msg;
1539          raw_string_ostream Msg(msg);
1540          Msg << "Invalid operand found in inline asm: '"
1541               << AsmStr << "'\n";
1542          MI->print(Msg);
1543          llvm_report_error(Msg.str());
1544        }
1545      }
1546      break;
1547    }
1548    }
1549  }
1550  O << "\n\t" << TAI->getInlineAsmEnd() << '\n';
1551}
1552
1553/// printImplicitDef - This method prints the specified machine instruction
1554/// that is an implicit def.
1555void AsmPrinter::printImplicitDef(const MachineInstr *MI) const {
1556  if (VerboseAsm)
1557    O << '\t' << TAI->getCommentString() << " implicit-def: "
1558      << TRI->getAsmName(MI->getOperand(0).getReg()) << '\n';
1559}
1560
1561/// printLabel - This method prints a local label used by debug and
1562/// exception handling tables.
1563void AsmPrinter::printLabel(const MachineInstr *MI) const {
1564  printLabel(MI->getOperand(0).getImm());
1565}
1566
1567void AsmPrinter::printLabel(unsigned Id) const {
1568  O << TAI->getPrivateGlobalPrefix() << "label" << Id << ":\n";
1569}
1570
1571/// printDeclare - This method prints a local variable declaration used by
1572/// debug tables.
1573/// FIXME: It doesn't really print anything rather it inserts a DebugVariable
1574/// entry into dwarf table.
1575void AsmPrinter::printDeclare(const MachineInstr *MI) const {
1576  unsigned FI = MI->getOperand(0).getIndex();
1577  GlobalValue *GV = MI->getOperand(1).getGlobal();
1578  DW->RecordVariable(cast<GlobalVariable>(GV), FI, MI);
1579}
1580
1581/// PrintAsmOperand - Print the specified operand of MI, an INLINEASM
1582/// instruction, using the specified assembler variant.  Targets should
1583/// overried this to format as appropriate.
1584bool AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
1585                                 unsigned AsmVariant, const char *ExtraCode) {
1586  // Target doesn't support this yet!
1587  return true;
1588}
1589
1590bool AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
1591                                       unsigned AsmVariant,
1592                                       const char *ExtraCode) {
1593  // Target doesn't support this yet!
1594  return true;
1595}
1596
1597/// printBasicBlockLabel - This method prints the label for the specified
1598/// MachineBasicBlock
1599void AsmPrinter::printBasicBlockLabel(const MachineBasicBlock *MBB,
1600                                      bool printAlign,
1601                                      bool printColon,
1602                                      bool printComment) const {
1603  if (printAlign) {
1604    unsigned Align = MBB->getAlignment();
1605    if (Align)
1606      EmitAlignment(Log2_32(Align));
1607  }
1608
1609  O << TAI->getPrivateGlobalPrefix() << "BB" << getFunctionNumber() << '_'
1610    << MBB->getNumber();
1611  if (printColon)
1612    O << ':';
1613  if (printComment && MBB->getBasicBlock())
1614    O << '\t' << TAI->getCommentString() << ' '
1615      << MBB->getBasicBlock()->getNameStart();
1616}
1617
1618/// printPICJumpTableSetLabel - This method prints a set label for the
1619/// specified MachineBasicBlock for a jumptable entry.
1620void AsmPrinter::printPICJumpTableSetLabel(unsigned uid,
1621                                           const MachineBasicBlock *MBB) const {
1622  if (!TAI->getSetDirective())
1623    return;
1624
1625  O << TAI->getSetDirective() << ' ' << TAI->getPrivateGlobalPrefix()
1626    << getFunctionNumber() << '_' << uid << "_set_" << MBB->getNumber() << ',';
1627  printBasicBlockLabel(MBB, false, false, false);
1628  O << '-' << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
1629    << '_' << uid << '\n';
1630}
1631
1632void AsmPrinter::printPICJumpTableSetLabel(unsigned uid, unsigned uid2,
1633                                           const MachineBasicBlock *MBB) const {
1634  if (!TAI->getSetDirective())
1635    return;
1636
1637  O << TAI->getSetDirective() << ' ' << TAI->getPrivateGlobalPrefix()
1638    << getFunctionNumber() << '_' << uid << '_' << uid2
1639    << "_set_" << MBB->getNumber() << ',';
1640  printBasicBlockLabel(MBB, false, false, false);
1641  O << '-' << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
1642    << '_' << uid << '_' << uid2 << '\n';
1643}
1644
1645/// printDataDirective - This method prints the asm directive for the
1646/// specified type.
1647void AsmPrinter::printDataDirective(const Type *type, unsigned AddrSpace) {
1648  const TargetData *TD = TM.getTargetData();
1649  switch (type->getTypeID()) {
1650  case Type::IntegerTyID: {
1651    unsigned BitWidth = cast<IntegerType>(type)->getBitWidth();
1652    if (BitWidth <= 8)
1653      O << TAI->getData8bitsDirective(AddrSpace);
1654    else if (BitWidth <= 16)
1655      O << TAI->getData16bitsDirective(AddrSpace);
1656    else if (BitWidth <= 32)
1657      O << TAI->getData32bitsDirective(AddrSpace);
1658    else if (BitWidth <= 64) {
1659      assert(TAI->getData64bitsDirective(AddrSpace) &&
1660             "Target cannot handle 64-bit constant exprs!");
1661      O << TAI->getData64bitsDirective(AddrSpace);
1662    } else {
1663      assert(0 && "Target cannot handle given data directive width!");
1664    }
1665    break;
1666  }
1667  case Type::PointerTyID:
1668    if (TD->getPointerSize() == 8) {
1669      assert(TAI->getData64bitsDirective(AddrSpace) &&
1670             "Target cannot handle 64-bit pointer exprs!");
1671      O << TAI->getData64bitsDirective(AddrSpace);
1672    } else if (TD->getPointerSize() == 2) {
1673      O << TAI->getData16bitsDirective(AddrSpace);
1674    } else if (TD->getPointerSize() == 1) {
1675      O << TAI->getData8bitsDirective(AddrSpace);
1676    } else {
1677      O << TAI->getData32bitsDirective(AddrSpace);
1678    }
1679    break;
1680  case Type::FloatTyID: case Type::DoubleTyID:
1681  case Type::X86_FP80TyID: case Type::FP128TyID: case Type::PPC_FP128TyID:
1682    assert (0 && "Should have already output floating point constant.");
1683  default:
1684    assert (0 && "Can't handle printing this type of thing");
1685    break;
1686  }
1687}
1688
1689void AsmPrinter::printSuffixedName(const char *Name, const char *Suffix,
1690                                   const char *Prefix) {
1691  if (Name[0]=='\"')
1692    O << '\"';
1693  O << TAI->getPrivateGlobalPrefix();
1694  if (Prefix) O << Prefix;
1695  if (Name[0]=='\"')
1696    O << '\"';
1697  if (Name[0]=='\"')
1698    O << Name[1];
1699  else
1700    O << Name;
1701  O << Suffix;
1702  if (Name[0]=='\"')
1703    O << '\"';
1704}
1705
1706void AsmPrinter::printSuffixedName(const std::string &Name, const char* Suffix) {
1707  printSuffixedName(Name.c_str(), Suffix);
1708}
1709
1710void AsmPrinter::printVisibility(const std::string& Name,
1711                                 unsigned Visibility) const {
1712  if (Visibility == GlobalValue::HiddenVisibility) {
1713    if (const char *Directive = TAI->getHiddenDirective())
1714      O << Directive << Name << '\n';
1715  } else if (Visibility == GlobalValue::ProtectedVisibility) {
1716    if (const char *Directive = TAI->getProtectedDirective())
1717      O << Directive << Name << '\n';
1718  }
1719}
1720
1721void AsmPrinter::printOffset(int64_t Offset) const {
1722  if (Offset > 0)
1723    O << '+' << Offset;
1724  else if (Offset < 0)
1725    O << Offset;
1726}
1727
1728GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1729  if (!S->usesMetadata())
1730    return 0;
1731
1732  gcp_iterator GCPI = GCMetadataPrinters.find(S);
1733  if (GCPI != GCMetadataPrinters.end())
1734    return GCPI->second;
1735
1736  const char *Name = S->getName().c_str();
1737
1738  for (GCMetadataPrinterRegistry::iterator
1739         I = GCMetadataPrinterRegistry::begin(),
1740         E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1741    if (strcmp(Name, I->getName()) == 0) {
1742      GCMetadataPrinter *GMP = I->instantiate();
1743      GMP->S = S;
1744      GCMetadataPrinters.insert(std::make_pair(S, GMP));
1745      return GMP;
1746    }
1747
1748  cerr << "no GCMetadataPrinter registered for GC: " << Name << "\n";
1749  llvm_unreachable();
1750}
1751