BitcodeWriter.cpp revision 0444de0c0e7cfc8d8f8fed6f64cd97812bdd6a41 
1//===--- Bitcode/Writer/BitcodeWriter.cpp - Bitcode Writer ----------------===//
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// Bitcode writer implementation.
11//
12//===----------------------------------------------------------------------===//
13
14#include "ReaderWriter_2_9_func.h"
15#include "llvm/Bitcode/BitstreamWriter.h"
16#include "llvm/Bitcode/LLVMBitCodes.h"
17#include "ValueEnumerator.h"
18#include "llvm/Constants.h"
19#include "llvm/DerivedTypes.h"
20#include "llvm/InlineAsm.h"
21#include "llvm/Instructions.h"
22#include "llvm/Module.h"
23#include "llvm/Operator.h"
24#include "llvm/ValueSymbolTable.h"
25#include "llvm/ADT/Triple.h"
26#include "llvm/Support/ErrorHandling.h"
27#include "llvm/Support/MathExtras.h"
28#include "llvm/Support/raw_ostream.h"
29#include "llvm/Support/Program.h"
30#include <cctype>
31#include <map>
32using namespace llvm;
33
34/// These are manifest constants used by the bitcode writer. They do not need to
35/// be kept in sync with the reader, but need to be consistent within this file.
36enum {
37  CurVersion = 0,
38
39  // VALUE_SYMTAB_BLOCK abbrev id's.
40  VST_ENTRY_8_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
41  VST_ENTRY_7_ABBREV,
42  VST_ENTRY_6_ABBREV,
43  VST_BBENTRY_6_ABBREV,
44
45  // CONSTANTS_BLOCK abbrev id's.
46  CONSTANTS_SETTYPE_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
47  CONSTANTS_INTEGER_ABBREV,
48  CONSTANTS_CE_CAST_Abbrev,
49  CONSTANTS_NULL_Abbrev,
50
51  // FUNCTION_BLOCK abbrev id's.
52  FUNCTION_INST_LOAD_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
53  FUNCTION_INST_BINOP_ABBREV,
54  FUNCTION_INST_BINOP_FLAGS_ABBREV,
55  FUNCTION_INST_CAST_ABBREV,
56  FUNCTION_INST_RET_VOID_ABBREV,
57  FUNCTION_INST_RET_VAL_ABBREV,
58  FUNCTION_INST_UNREACHABLE_ABBREV
59};
60
61static unsigned GetEncodedCastOpcode(unsigned Opcode) {
62  switch (Opcode) {
63  default: llvm_unreachable("Unknown cast instruction!");
64  case Instruction::Trunc   : return bitc::CAST_TRUNC;
65  case Instruction::ZExt    : return bitc::CAST_ZEXT;
66  case Instruction::SExt    : return bitc::CAST_SEXT;
67  case Instruction::FPToUI  : return bitc::CAST_FPTOUI;
68  case Instruction::FPToSI  : return bitc::CAST_FPTOSI;
69  case Instruction::UIToFP  : return bitc::CAST_UITOFP;
70  case Instruction::SIToFP  : return bitc::CAST_SITOFP;
71  case Instruction::FPTrunc : return bitc::CAST_FPTRUNC;
72  case Instruction::FPExt   : return bitc::CAST_FPEXT;
73  case Instruction::PtrToInt: return bitc::CAST_PTRTOINT;
74  case Instruction::IntToPtr: return bitc::CAST_INTTOPTR;
75  case Instruction::BitCast : return bitc::CAST_BITCAST;
76  }
77}
78
79static unsigned GetEncodedBinaryOpcode(unsigned Opcode) {
80  switch (Opcode) {
81  default: llvm_unreachable("Unknown binary instruction!");
82  case Instruction::Add:
83  case Instruction::FAdd: return bitc::BINOP_ADD;
84  case Instruction::Sub:
85  case Instruction::FSub: return bitc::BINOP_SUB;
86  case Instruction::Mul:
87  case Instruction::FMul: return bitc::BINOP_MUL;
88  case Instruction::UDiv: return bitc::BINOP_UDIV;
89  case Instruction::FDiv:
90  case Instruction::SDiv: return bitc::BINOP_SDIV;
91  case Instruction::URem: return bitc::BINOP_UREM;
92  case Instruction::FRem:
93  case Instruction::SRem: return bitc::BINOP_SREM;
94  case Instruction::Shl:  return bitc::BINOP_SHL;
95  case Instruction::LShr: return bitc::BINOP_LSHR;
96  case Instruction::AShr: return bitc::BINOP_ASHR;
97  case Instruction::And:  return bitc::BINOP_AND;
98  case Instruction::Or:   return bitc::BINOP_OR;
99  case Instruction::Xor:  return bitc::BINOP_XOR;
100  }
101}
102
103static unsigned GetEncodedRMWOperation(AtomicRMWInst::BinOp Op) {
104  switch (Op) {
105  default: llvm_unreachable("Unknown RMW operation!");
106  case AtomicRMWInst::Xchg: return bitc::RMW_XCHG;
107  case AtomicRMWInst::Add: return bitc::RMW_ADD;
108  case AtomicRMWInst::Sub: return bitc::RMW_SUB;
109  case AtomicRMWInst::And: return bitc::RMW_AND;
110  case AtomicRMWInst::Nand: return bitc::RMW_NAND;
111  case AtomicRMWInst::Or: return bitc::RMW_OR;
112  case AtomicRMWInst::Xor: return bitc::RMW_XOR;
113  case AtomicRMWInst::Max: return bitc::RMW_MAX;
114  case AtomicRMWInst::Min: return bitc::RMW_MIN;
115  case AtomicRMWInst::UMax: return bitc::RMW_UMAX;
116  case AtomicRMWInst::UMin: return bitc::RMW_UMIN;
117  }
118}
119
120static unsigned GetEncodedOrdering(AtomicOrdering Ordering) {
121  switch (Ordering) {
122  default: llvm_unreachable("Unknown atomic ordering");
123  case NotAtomic: return bitc::ORDERING_NOTATOMIC;
124  case Unordered: return bitc::ORDERING_UNORDERED;
125  case Monotonic: return bitc::ORDERING_MONOTONIC;
126  case Acquire: return bitc::ORDERING_ACQUIRE;
127  case Release: return bitc::ORDERING_RELEASE;
128  case AcquireRelease: return bitc::ORDERING_ACQREL;
129  case SequentiallyConsistent: return bitc::ORDERING_SEQCST;
130  }
131}
132
133static unsigned GetEncodedSynchScope(SynchronizationScope SynchScope) {
134  switch (SynchScope) {
135  default: llvm_unreachable("Unknown synchronization scope");
136  case SingleThread: return bitc::SYNCHSCOPE_SINGLETHREAD;
137  case CrossThread: return bitc::SYNCHSCOPE_CROSSTHREAD;
138  }
139}
140
141static void WriteStringRecord(unsigned Code, StringRef Str,
142                              unsigned AbbrevToUse, BitstreamWriter &Stream) {
143  SmallVector<unsigned, 64> Vals;
144
145  // Code: [strchar x N]
146  for (unsigned i = 0, e = Str.size(); i != e; ++i) {
147    if (AbbrevToUse && !BitCodeAbbrevOp::isChar6(Str[i]))
148      AbbrevToUse = 0;
149    Vals.push_back(Str[i]);
150  }
151
152  // Emit the finished record.
153  Stream.EmitRecord(Code, Vals, AbbrevToUse);
154}
155
156// Emit information about parameter attributes.
157static void WriteAttributeTable(const ValueEnumerator &VE,
158                                BitstreamWriter &Stream) {
159  const std::vector<AttrListPtr> &Attrs = VE.getAttributes();
160  if (Attrs.empty()) return;
161
162  Stream.EnterSubblock(bitc::PARAMATTR_BLOCK_ID, 3);
163
164  SmallVector<uint64_t, 64> Record;
165  for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
166    const AttrListPtr &A = Attrs[i];
167    for (unsigned i = 0, e = A.getNumSlots(); i != e; ++i) {
168      const AttributeWithIndex &PAWI = A.getSlot(i);
169      Record.push_back(PAWI.Index);
170
171      // FIXME: remove in LLVM 3.0
172      // Store the alignment in the bitcode as a 16-bit raw value instead of a
173      // 5-bit log2 encoded value. Shift the bits above the alignment up by
174      // 11 bits.
175      uint64_t FauxAttr = PAWI.Attrs.Raw() & 0xffff;
176      if (PAWI.Attrs & Attribute::Alignment)
177        FauxAttr |= (1ull<<16)<<
178            (((PAWI.Attrs & Attribute::Alignment).Raw()-1) >> 16);
179      FauxAttr |= (PAWI.Attrs.Raw() & (0x3FFull << 21)) << 11;
180
181      Record.push_back(FauxAttr);
182    }
183
184    Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY, Record);
185    Record.clear();
186  }
187
188  Stream.ExitBlock();
189}
190
191/// WriteTypeTable - Write out the type table for a module.
192static void WriteTypeTable(const ValueEnumerator &VE, BitstreamWriter &Stream) {
193  const ValueEnumerator::TypeList &TypeList = VE.getTypes();
194
195  Stream.EnterSubblock(bitc::TYPE_BLOCK_ID_NEW, 4 /*count from # abbrevs */);
196  SmallVector<uint64_t, 64> TypeVals;
197
198  // Abbrev for TYPE_CODE_POINTER.
199  BitCodeAbbrev *Abbv = new BitCodeAbbrev();
200  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_POINTER));
201  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
202                            Log2_32_Ceil(VE.getTypes().size()+1)));
203  Abbv->Add(BitCodeAbbrevOp(0));  // Addrspace = 0
204  unsigned PtrAbbrev = Stream.EmitAbbrev(Abbv);
205
206  // Abbrev for TYPE_CODE_FUNCTION.
207  Abbv = new BitCodeAbbrev();
208  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_FUNCTION_OLD));
209  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // isvararg
210  Abbv->Add(BitCodeAbbrevOp(0));  // FIXME: DEAD value, remove in LLVM 3.0
211  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
212  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
213                            Log2_32_Ceil(VE.getTypes().size()+1)));
214  unsigned FunctionAbbrev = Stream.EmitAbbrev(Abbv);
215
216  // Abbrev for TYPE_CODE_STRUCT_ANON.
217  Abbv = new BitCodeAbbrev();
218  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_ANON));
219  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // ispacked
220  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
221  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
222                            Log2_32_Ceil(VE.getTypes().size()+1)));
223  unsigned StructAnonAbbrev = Stream.EmitAbbrev(Abbv);
224
225  // Abbrev for TYPE_CODE_STRUCT_NAME.
226  Abbv = new BitCodeAbbrev();
227  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_NAME));
228  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
229  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
230  unsigned StructNameAbbrev = Stream.EmitAbbrev(Abbv);
231
232  // Abbrev for TYPE_CODE_STRUCT_NAMED.
233  Abbv = new BitCodeAbbrev();
234  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_NAMED));
235  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // ispacked
236  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
237  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
238                            Log2_32_Ceil(VE.getTypes().size()+1)));
239  unsigned StructNamedAbbrev = Stream.EmitAbbrev(Abbv);
240
241  // Abbrev for TYPE_CODE_ARRAY.
242  Abbv = new BitCodeAbbrev();
243  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_ARRAY));
244  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // size
245  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
246                            Log2_32_Ceil(VE.getTypes().size()+1)));
247  unsigned ArrayAbbrev = Stream.EmitAbbrev(Abbv);
248
249  // Emit an entry count so the reader can reserve space.
250  TypeVals.push_back(TypeList.size());
251  Stream.EmitRecord(bitc::TYPE_CODE_NUMENTRY, TypeVals);
252  TypeVals.clear();
253
254  // Loop over all of the types, emitting each in turn.
255  for (unsigned i = 0, e = TypeList.size(); i != e; ++i) {
256    Type *T = TypeList[i];
257    int AbbrevToUse = 0;
258    unsigned Code = 0;
259
260    switch (T->getTypeID()) {
261    default: llvm_unreachable("Unknown type!");
262    case Type::VoidTyID:      Code = bitc::TYPE_CODE_VOID;   break;
263    case Type::FloatTyID:     Code = bitc::TYPE_CODE_FLOAT;  break;
264    case Type::DoubleTyID:    Code = bitc::TYPE_CODE_DOUBLE; break;
265    case Type::X86_FP80TyID:  Code = bitc::TYPE_CODE_X86_FP80; break;
266    case Type::FP128TyID:     Code = bitc::TYPE_CODE_FP128; break;
267    case Type::PPC_FP128TyID: Code = bitc::TYPE_CODE_PPC_FP128; break;
268    case Type::LabelTyID:     Code = bitc::TYPE_CODE_LABEL;  break;
269    case Type::MetadataTyID:  Code = bitc::TYPE_CODE_METADATA; break;
270    case Type::X86_MMXTyID:   Code = bitc::TYPE_CODE_X86_MMX; break;
271    case Type::IntegerTyID:
272      // INTEGER: [width]
273      Code = bitc::TYPE_CODE_INTEGER;
274      TypeVals.push_back(cast<IntegerType>(T)->getBitWidth());
275      break;
276    case Type::PointerTyID: {
277      PointerType *PTy = cast<PointerType>(T);
278      // POINTER: [pointee type, address space]
279      Code = bitc::TYPE_CODE_POINTER;
280      TypeVals.push_back(VE.getTypeID(PTy->getElementType()));
281      unsigned AddressSpace = PTy->getAddressSpace();
282      TypeVals.push_back(AddressSpace);
283      if (AddressSpace == 0) AbbrevToUse = PtrAbbrev;
284      break;
285    }
286    case Type::FunctionTyID: {
287      FunctionType *FT = cast<FunctionType>(T);
288      // FUNCTION: [isvararg, attrid, retty, paramty x N]
289      Code = bitc::TYPE_CODE_FUNCTION_OLD;
290      TypeVals.push_back(FT->isVarArg());
291      TypeVals.push_back(0);  // FIXME: DEAD: remove in llvm 3.0
292      TypeVals.push_back(VE.getTypeID(FT->getReturnType()));
293      for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i)
294        TypeVals.push_back(VE.getTypeID(FT->getParamType(i)));
295      AbbrevToUse = FunctionAbbrev;
296      break;
297    }
298    case Type::StructTyID: {
299      StructType *ST = cast<StructType>(T);
300      // STRUCT: [ispacked, eltty x N]
301      TypeVals.push_back(ST->isPacked());
302      // Output all of the element types.
303      for (StructType::element_iterator I = ST->element_begin(),
304           E = ST->element_end(); I != E; ++I)
305        TypeVals.push_back(VE.getTypeID(*I));
306
307      if (ST->isLiteral()) {
308        Code = bitc::TYPE_CODE_STRUCT_ANON;
309        AbbrevToUse = StructAnonAbbrev;
310      } else {
311        if (ST->isOpaque()) {
312          Code = bitc::TYPE_CODE_OPAQUE;
313        } else {
314          Code = bitc::TYPE_CODE_STRUCT_NAMED;
315          AbbrevToUse = StructNamedAbbrev;
316        }
317
318        // Emit the name if it is present.
319        if (!ST->getName().empty())
320          WriteStringRecord(bitc::TYPE_CODE_STRUCT_NAME, ST->getName(),
321                            StructNameAbbrev, Stream);
322      }
323      break;
324    }
325    case Type::ArrayTyID: {
326      ArrayType *AT = cast<ArrayType>(T);
327      // ARRAY: [numelts, eltty]
328      Code = bitc::TYPE_CODE_ARRAY;
329      TypeVals.push_back(AT->getNumElements());
330      TypeVals.push_back(VE.getTypeID(AT->getElementType()));
331      AbbrevToUse = ArrayAbbrev;
332      break;
333    }
334    case Type::VectorTyID: {
335      VectorType *VT = cast<VectorType>(T);
336      // VECTOR [numelts, eltty]
337      Code = bitc::TYPE_CODE_VECTOR;
338      TypeVals.push_back(VT->getNumElements());
339      TypeVals.push_back(VE.getTypeID(VT->getElementType()));
340      break;
341    }
342    }
343
344    // Emit the finished record.
345    Stream.EmitRecord(Code, TypeVals, AbbrevToUse);
346    TypeVals.clear();
347  }
348
349  Stream.ExitBlock();
350}
351
352static unsigned getEncodedLinkage(const GlobalValue *GV) {
353  switch (GV->getLinkage()) {
354  default: llvm_unreachable("Invalid linkage!");
355  case GlobalValue::ExternalLinkage:                 return 0;
356  case GlobalValue::WeakAnyLinkage:                  return 1;
357  case GlobalValue::AppendingLinkage:                return 2;
358  case GlobalValue::InternalLinkage:                 return 3;
359  case GlobalValue::LinkOnceAnyLinkage:              return 4;
360  case GlobalValue::DLLImportLinkage:                return 5;
361  case GlobalValue::DLLExportLinkage:                return 6;
362  case GlobalValue::ExternalWeakLinkage:             return 7;
363  case GlobalValue::CommonLinkage:                   return 8;
364  case GlobalValue::PrivateLinkage:                  return 9;
365  case GlobalValue::WeakODRLinkage:                  return 10;
366  case GlobalValue::LinkOnceODRLinkage:              return 11;
367  case GlobalValue::AvailableExternallyLinkage:      return 12;
368  case GlobalValue::LinkerPrivateLinkage:            return 13;
369  case GlobalValue::LinkerPrivateWeakLinkage:        return 14;
370  case GlobalValue::LinkerPrivateWeakDefAutoLinkage: return 15;
371  }
372}
373
374static unsigned getEncodedVisibility(const GlobalValue *GV) {
375  switch (GV->getVisibility()) {
376  default: llvm_unreachable("Invalid visibility!");
377  case GlobalValue::DefaultVisibility:   return 0;
378  case GlobalValue::HiddenVisibility:    return 1;
379  case GlobalValue::ProtectedVisibility: return 2;
380  }
381}
382
383// Emit top-level description of module, including target triple, inline asm,
384// descriptors for global variables, and function prototype info.
385static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
386                            BitstreamWriter &Stream) {
387  // Emit the list of dependent libraries for the Module.
388  for (Module::lib_iterator I = M->lib_begin(), E = M->lib_end(); I != E; ++I)
389    WriteStringRecord(bitc::MODULE_CODE_DEPLIB, *I, 0/*TODO*/, Stream);
390
391  // Emit various pieces of data attached to a module.
392  if (!M->getTargetTriple().empty())
393    WriteStringRecord(bitc::MODULE_CODE_TRIPLE, M->getTargetTriple(),
394                      0/*TODO*/, Stream);
395  if (!M->getDataLayout().empty())
396    WriteStringRecord(bitc::MODULE_CODE_DATALAYOUT, M->getDataLayout(),
397                      0/*TODO*/, Stream);
398  if (!M->getModuleInlineAsm().empty())
399    WriteStringRecord(bitc::MODULE_CODE_ASM, M->getModuleInlineAsm(),
400                      0/*TODO*/, Stream);
401
402  // Emit information about sections and GC, computing how many there are. Also
403  // compute the maximum alignment value.
404  std::map<std::string, unsigned> SectionMap;
405  std::map<std::string, unsigned> GCMap;
406  unsigned MaxAlignment = 0;
407  unsigned MaxGlobalType = 0;
408  for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end();
409       GV != E; ++GV) {
410    MaxAlignment = std::max(MaxAlignment, GV->getAlignment());
411    MaxGlobalType = std::max(MaxGlobalType, VE.getTypeID(GV->getType()));
412    if (GV->hasSection()) {
413      // Give section names unique ID's.
414      unsigned &Entry = SectionMap[GV->getSection()];
415      if (!Entry) {
416        WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, GV->getSection(),
417                          0/*TODO*/, Stream);
418        Entry = SectionMap.size();
419      }
420    }
421  }
422  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
423    MaxAlignment = std::max(MaxAlignment, F->getAlignment());
424    if (F->hasSection()) {
425      // Give section names unique ID's.
426      unsigned &Entry = SectionMap[F->getSection()];
427      if (!Entry) {
428        WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F->getSection(),
429                          0/*TODO*/, Stream);
430        Entry = SectionMap.size();
431      }
432    }
433    if (F->hasGC()) {
434      // Same for GC names.
435      unsigned &Entry = GCMap[F->getGC()];
436      if (!Entry) {
437        WriteStringRecord(bitc::MODULE_CODE_GCNAME, F->getGC(),
438                          0/*TODO*/, Stream);
439        Entry = GCMap.size();
440      }
441    }
442  }
443
444  // Emit abbrev for globals, now that we know # sections and max alignment.
445  unsigned SimpleGVarAbbrev = 0;
446  if (!M->global_empty()) {
447    // Add an abbrev for common globals with no visibility or thread localness.
448    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
449    Abbv->Add(BitCodeAbbrevOp(bitc::MODULE_CODE_GLOBALVAR));
450    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
451                              Log2_32_Ceil(MaxGlobalType+1)));
452    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));      // Constant.
453    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));        // Initializer.
454    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));      // Linkage.
455    if (MaxAlignment == 0)                                      // Alignment.
456      Abbv->Add(BitCodeAbbrevOp(0));
457    else {
458      unsigned MaxEncAlignment = Log2_32(MaxAlignment)+1;
459      Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
460                               Log2_32_Ceil(MaxEncAlignment+1)));
461    }
462    if (SectionMap.empty())                                    // Section.
463      Abbv->Add(BitCodeAbbrevOp(0));
464    else
465      Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
466                               Log2_32_Ceil(SectionMap.size()+1)));
467    // Don't bother emitting vis + thread local.
468    SimpleGVarAbbrev = Stream.EmitAbbrev(Abbv);
469  }
470
471  // Emit the global variable information.
472  SmallVector<unsigned, 64> Vals;
473  for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end();
474       GV != E; ++GV) {
475    unsigned AbbrevToUse = 0;
476
477    // GLOBALVAR: [type, isconst, initid,
478    //             linkage, alignment, section, visibility, threadlocal,
479    //             unnamed_addr]
480    Vals.push_back(VE.getTypeID(GV->getType()));
481    Vals.push_back(GV->isConstant());
482    Vals.push_back(GV->isDeclaration() ? 0 :
483                   (VE.getValueID(GV->getInitializer()) + 1));
484    Vals.push_back(getEncodedLinkage(GV));
485    Vals.push_back(Log2_32(GV->getAlignment())+1);
486    Vals.push_back(GV->hasSection() ? SectionMap[GV->getSection()] : 0);
487    if (GV->isThreadLocal() ||
488        GV->getVisibility() != GlobalValue::DefaultVisibility ||
489        GV->hasUnnamedAddr()) {
490      Vals.push_back(getEncodedVisibility(GV));
491      Vals.push_back(GV->isThreadLocal());
492      Vals.push_back(GV->hasUnnamedAddr());
493    } else {
494      AbbrevToUse = SimpleGVarAbbrev;
495    }
496
497    Stream.EmitRecord(bitc::MODULE_CODE_GLOBALVAR, Vals, AbbrevToUse);
498    Vals.clear();
499  }
500
501  // Emit the function proto information.
502  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
503    // FUNCTION:  [type, callingconv, isproto, paramattr,
504    //             linkage, alignment, section, visibility, gc, unnamed_addr]
505    Vals.push_back(VE.getTypeID(F->getType()));
506    Vals.push_back(F->getCallingConv());
507    Vals.push_back(F->isDeclaration());
508    Vals.push_back(getEncodedLinkage(F));
509    Vals.push_back(VE.getAttributeID(F->getAttributes()));
510    Vals.push_back(Log2_32(F->getAlignment())+1);
511    Vals.push_back(F->hasSection() ? SectionMap[F->getSection()] : 0);
512    Vals.push_back(getEncodedVisibility(F));
513    Vals.push_back(F->hasGC() ? GCMap[F->getGC()] : 0);
514    Vals.push_back(F->hasUnnamedAddr());
515
516    unsigned AbbrevToUse = 0;
517    Stream.EmitRecord(bitc::MODULE_CODE_FUNCTION, Vals, AbbrevToUse);
518    Vals.clear();
519  }
520
521  // Emit the alias information.
522  for (Module::const_alias_iterator AI = M->alias_begin(), E = M->alias_end();
523       AI != E; ++AI) {
524    Vals.push_back(VE.getTypeID(AI->getType()));
525    Vals.push_back(VE.getValueID(AI->getAliasee()));
526    Vals.push_back(getEncodedLinkage(AI));
527    Vals.push_back(getEncodedVisibility(AI));
528    unsigned AbbrevToUse = 0;
529    Stream.EmitRecord(bitc::MODULE_CODE_ALIAS, Vals, AbbrevToUse);
530    Vals.clear();
531  }
532}
533
534static uint64_t GetOptimizationFlags(const Value *V) {
535  uint64_t Flags = 0;
536
537  if (const OverflowingBinaryOperator *OBO =
538        dyn_cast<OverflowingBinaryOperator>(V)) {
539    if (OBO->hasNoSignedWrap())
540      Flags |= 1 << bitc::OBO_NO_SIGNED_WRAP;
541    if (OBO->hasNoUnsignedWrap())
542      Flags |= 1 << bitc::OBO_NO_UNSIGNED_WRAP;
543  } else if (const PossiblyExactOperator *PEO =
544               dyn_cast<PossiblyExactOperator>(V)) {
545    if (PEO->isExact())
546      Flags |= 1 << bitc::PEO_EXACT;
547  }
548
549  return Flags;
550}
551
552static void WriteMDNode(const MDNode *N,
553                        const ValueEnumerator &VE,
554                        BitstreamWriter &Stream,
555                        SmallVector<uint64_t, 64> &Record) {
556  for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
557    if (N->getOperand(i)) {
558      Record.push_back(VE.getTypeID(N->getOperand(i)->getType()));
559      Record.push_back(VE.getValueID(N->getOperand(i)));
560    } else {
561      Record.push_back(VE.getTypeID(Type::getVoidTy(N->getContext())));
562      Record.push_back(0);
563    }
564  }
565  unsigned MDCode = N->isFunctionLocal() ? bitc::METADATA_FN_NODE :
566                                           bitc::METADATA_NODE;
567  Stream.EmitRecord(MDCode, Record, 0);
568  Record.clear();
569}
570
571static void WriteModuleMetadata(const Module *M,
572                                const ValueEnumerator &VE,
573                                BitstreamWriter &Stream) {
574  const ValueEnumerator::ValueList &Vals = VE.getMDValues();
575  bool StartedMetadataBlock = false;
576  unsigned MDSAbbrev = 0;
577  SmallVector<uint64_t, 64> Record;
578  for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
579
580    if (const MDNode *N = dyn_cast<MDNode>(Vals[i].first)) {
581      if (!N->isFunctionLocal() || !N->getFunction()) {
582        if (!StartedMetadataBlock) {
583          Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
584          StartedMetadataBlock = true;
585        }
586        WriteMDNode(N, VE, Stream, Record);
587      }
588    } else if (const MDString *MDS = dyn_cast<MDString>(Vals[i].first)) {
589      if (!StartedMetadataBlock)  {
590        Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
591
592        // Abbrev for METADATA_STRING.
593        BitCodeAbbrev *Abbv = new BitCodeAbbrev();
594        Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_STRING));
595        Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
596        Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
597        MDSAbbrev = Stream.EmitAbbrev(Abbv);
598        StartedMetadataBlock = true;
599      }
600
601      // Code: [strchar x N]
602      Record.append(MDS->begin(), MDS->end());
603
604      // Emit the finished record.
605      Stream.EmitRecord(bitc::METADATA_STRING, Record, MDSAbbrev);
606      Record.clear();
607    }
608  }
609
610  // Write named metadata.
611  for (Module::const_named_metadata_iterator I = M->named_metadata_begin(),
612       E = M->named_metadata_end(); I != E; ++I) {
613    const NamedMDNode *NMD = I;
614    if (!StartedMetadataBlock)  {
615      Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
616      StartedMetadataBlock = true;
617    }
618
619    // Write name.
620    StringRef Str = NMD->getName();
621    for (unsigned i = 0, e = Str.size(); i != e; ++i)
622      Record.push_back(Str[i]);
623    Stream.EmitRecord(bitc::METADATA_NAME, Record, 0/*TODO*/);
624    Record.clear();
625
626    // Write named metadata operands.
627    for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i)
628      Record.push_back(VE.getValueID(NMD->getOperand(i)));
629    Stream.EmitRecord(bitc::METADATA_NAMED_NODE, Record, 0);
630    Record.clear();
631  }
632
633  if (StartedMetadataBlock)
634    Stream.ExitBlock();
635}
636
637static void WriteFunctionLocalMetadata(const Function &F,
638                                       const ValueEnumerator &VE,
639                                       BitstreamWriter &Stream) {
640  bool StartedMetadataBlock = false;
641  SmallVector<uint64_t, 64> Record;
642  const SmallVector<const MDNode *, 8> &Vals = VE.getFunctionLocalMDValues();
643  for (unsigned i = 0, e = Vals.size(); i != e; ++i)
644    if (const MDNode *N = Vals[i])
645      if (N->isFunctionLocal() && N->getFunction() == &F) {
646        if (!StartedMetadataBlock) {
647          Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
648          StartedMetadataBlock = true;
649        }
650        WriteMDNode(N, VE, Stream, Record);
651      }
652
653  if (StartedMetadataBlock)
654    Stream.ExitBlock();
655}
656
657static void WriteMetadataAttachment(const Function &F,
658                                    const ValueEnumerator &VE,
659                                    BitstreamWriter &Stream) {
660  Stream.EnterSubblock(bitc::METADATA_ATTACHMENT_ID, 3);
661
662  SmallVector<uint64_t, 64> Record;
663
664  // Write metadata attachments
665  // METADATA_ATTACHMENT - [m x [value, [n x [id, mdnode]]]
666  SmallVector<std::pair<unsigned, MDNode*>, 4> MDs;
667
668  for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
669    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
670         I != E; ++I) {
671      MDs.clear();
672      I->getAllMetadataOtherThanDebugLoc(MDs);
673
674      // If no metadata, ignore instruction.
675      if (MDs.empty()) continue;
676
677      Record.push_back(VE.getInstructionID(I));
678
679      for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
680        Record.push_back(MDs[i].first);
681        Record.push_back(VE.getValueID(MDs[i].second));
682      }
683      Stream.EmitRecord(bitc::METADATA_ATTACHMENT, Record, 0);
684      Record.clear();
685    }
686
687  Stream.ExitBlock();
688}
689
690static void WriteModuleMetadataStore(const Module *M, BitstreamWriter &Stream) {
691  SmallVector<uint64_t, 64> Record;
692
693  // Write metadata kinds
694  // METADATA_KIND - [n x [id, name]]
695  SmallVector<StringRef, 4> Names;
696  M->getMDKindNames(Names);
697
698  if (Names.empty()) return;
699
700  Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
701
702  for (unsigned MDKindID = 0, e = Names.size(); MDKindID != e; ++MDKindID) {
703    Record.push_back(MDKindID);
704    StringRef KName = Names[MDKindID];
705    Record.append(KName.begin(), KName.end());
706
707    Stream.EmitRecord(bitc::METADATA_KIND, Record, 0);
708    Record.clear();
709  }
710
711  Stream.ExitBlock();
712}
713
714static void WriteConstants(unsigned FirstVal, unsigned LastVal,
715                           const ValueEnumerator &VE,
716                           BitstreamWriter &Stream, bool isGlobal) {
717  if (FirstVal == LastVal) return;
718
719  Stream.EnterSubblock(bitc::CONSTANTS_BLOCK_ID, 4);
720
721  unsigned AggregateAbbrev = 0;
722  unsigned String8Abbrev = 0;
723  unsigned CString7Abbrev = 0;
724  unsigned CString6Abbrev = 0;
725  // If this is a constant pool for the module, emit module-specific abbrevs.
726  if (isGlobal) {
727    // Abbrev for CST_CODE_AGGREGATE.
728    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
729    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_AGGREGATE));
730    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
731    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, Log2_32_Ceil(LastVal+1)));
732    AggregateAbbrev = Stream.EmitAbbrev(Abbv);
733
734    // Abbrev for CST_CODE_STRING.
735    Abbv = new BitCodeAbbrev();
736    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_STRING));
737    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
738    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
739    String8Abbrev = Stream.EmitAbbrev(Abbv);
740    // Abbrev for CST_CODE_CSTRING.
741    Abbv = new BitCodeAbbrev();
742    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
743    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
744    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
745    CString7Abbrev = Stream.EmitAbbrev(Abbv);
746    // Abbrev for CST_CODE_CSTRING.
747    Abbv = new BitCodeAbbrev();
748    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
749    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
750    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
751    CString6Abbrev = Stream.EmitAbbrev(Abbv);
752  }
753
754  SmallVector<uint64_t, 64> Record;
755
756  const ValueEnumerator::ValueList &Vals = VE.getValues();
757  Type *LastTy = 0;
758  for (unsigned i = FirstVal; i != LastVal; ++i) {
759    const Value *V = Vals[i].first;
760    // If we need to switch types, do so now.
761    if (V->getType() != LastTy) {
762      LastTy = V->getType();
763      Record.push_back(VE.getTypeID(LastTy));
764      Stream.EmitRecord(bitc::CST_CODE_SETTYPE, Record,
765                        CONSTANTS_SETTYPE_ABBREV);
766      Record.clear();
767    }
768
769    if (const InlineAsm *IA = dyn_cast<InlineAsm>(V)) {
770      Record.push_back(unsigned(IA->hasSideEffects()) |
771                       unsigned(IA->isAlignStack()) << 1);
772
773      // Add the asm string.
774      const std::string &AsmStr = IA->getAsmString();
775      Record.push_back(AsmStr.size());
776      for (unsigned i = 0, e = AsmStr.size(); i != e; ++i)
777        Record.push_back(AsmStr[i]);
778
779      // Add the constraint string.
780      const std::string &ConstraintStr = IA->getConstraintString();
781      Record.push_back(ConstraintStr.size());
782      for (unsigned i = 0, e = ConstraintStr.size(); i != e; ++i)
783        Record.push_back(ConstraintStr[i]);
784      Stream.EmitRecord(bitc::CST_CODE_INLINEASM, Record);
785      Record.clear();
786      continue;
787    }
788    const Constant *C = cast<Constant>(V);
789    unsigned Code = -1U;
790    unsigned AbbrevToUse = 0;
791    if (C->isNullValue()) {
792      Code = bitc::CST_CODE_NULL;
793    } else if (isa<UndefValue>(C)) {
794      Code = bitc::CST_CODE_UNDEF;
795    } else if (const ConstantInt *IV = dyn_cast<ConstantInt>(C)) {
796      if (IV->getBitWidth() <= 64) {
797        uint64_t V = IV->getSExtValue();
798        if ((int64_t)V >= 0)
799          Record.push_back(V << 1);
800        else
801          Record.push_back((-V << 1) | 1);
802        Code = bitc::CST_CODE_INTEGER;
803        AbbrevToUse = CONSTANTS_INTEGER_ABBREV;
804      } else {                             // Wide integers, > 64 bits in size.
805        // We have an arbitrary precision integer value to write whose
806        // bit width is > 64. However, in canonical unsigned integer
807        // format it is likely that the high bits are going to be zero.
808        // So, we only write the number of active words.
809        unsigned NWords = IV->getValue().getActiveWords();
810        const uint64_t *RawWords = IV->getValue().getRawData();
811        for (unsigned i = 0; i != NWords; ++i) {
812          int64_t V = RawWords[i];
813          if (V >= 0)
814            Record.push_back(V << 1);
815          else
816            Record.push_back((-V << 1) | 1);
817        }
818        Code = bitc::CST_CODE_WIDE_INTEGER;
819      }
820    } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
821      Code = bitc::CST_CODE_FLOAT;
822      Type *Ty = CFP->getType();
823      if (Ty->isFloatTy() || Ty->isDoubleTy()) {
824        Record.push_back(CFP->getValueAPF().bitcastToAPInt().getZExtValue());
825      } else if (Ty->isX86_FP80Ty()) {
826        // api needed to prevent premature destruction
827        // bits are not in the same order as a normal i80 APInt, compensate.
828        APInt api = CFP->getValueAPF().bitcastToAPInt();
829        const uint64_t *p = api.getRawData();
830        Record.push_back((p[1] << 48) | (p[0] >> 16));
831        Record.push_back(p[0] & 0xffffLL);
832      } else if (Ty->isFP128Ty() || Ty->isPPC_FP128Ty()) {
833        APInt api = CFP->getValueAPF().bitcastToAPInt();
834        const uint64_t *p = api.getRawData();
835        Record.push_back(p[0]);
836        Record.push_back(p[1]);
837      } else {
838        assert (0 && "Unknown FP type!");
839      }
840    } else if (isa<ConstantDataSequential>(C) &&
841               cast<ConstantDataSequential>(C)->isString()) {
842      const ConstantDataSequential *Str = cast<ConstantDataSequential>(C);
843      // Emit constant strings specially.
844      unsigned NumElts = Str->getNumElements();
845      // If this is a null-terminated string, use the denser CSTRING encoding.
846      if (Str->isCString()) {
847        Code = bitc::CST_CODE_CSTRING;
848        --NumElts;  // Don't encode the null, which isn't allowed by char6.
849      } else {
850        Code = bitc::CST_CODE_STRING;
851        AbbrevToUse = String8Abbrev;
852      }
853      bool isCStr7 = Code == bitc::CST_CODE_CSTRING;
854      bool isCStrChar6 = Code == bitc::CST_CODE_CSTRING;
855      for (unsigned i = 0; i != NumElts; ++i) {
856        unsigned char V = Str->getElementAsInteger(i);
857        Record.push_back(V);
858        isCStr7 &= (V & 128) == 0;
859        if (isCStrChar6)
860          isCStrChar6 = BitCodeAbbrevOp::isChar6(V);
861      }
862
863      if (isCStrChar6)
864        AbbrevToUse = CString6Abbrev;
865      else if (isCStr7)
866        AbbrevToUse = CString7Abbrev;
867    } else if (const ConstantDataSequential *CDS =
868                  dyn_cast<ConstantDataSequential>(C)) {
869      Code = bitc::CST_CODE_DATA;
870      Type *EltTy = CDS->getType()->getElementType();
871      if (isa<IntegerType>(EltTy)) {
872        for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i)
873          Record.push_back(CDS->getElementAsInteger(i));
874      } else if (EltTy->isFloatTy()) {
875        for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
876          union { float F; uint32_t I; };
877          F = CDS->getElementAsFloat(i);
878          Record.push_back(I);
879        }
880      } else {
881        assert(EltTy->isDoubleTy() && "Unknown ConstantData element type");
882        for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
883          union { double F; uint64_t I; };
884          F = CDS->getElementAsDouble(i);
885          Record.push_back(I);
886        }
887      }
888    } else if (isa<ConstantArray>(C) || isa<ConstantStruct>(C) ||
889               isa<ConstantVector>(C)) {
890      Code = bitc::CST_CODE_AGGREGATE;
891      for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i)
892        Record.push_back(VE.getValueID(C->getOperand(i)));
893      AbbrevToUse = AggregateAbbrev;
894    } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
895      switch (CE->getOpcode()) {
896      default:
897        if (Instruction::isCast(CE->getOpcode())) {
898          Code = bitc::CST_CODE_CE_CAST;
899          Record.push_back(GetEncodedCastOpcode(CE->getOpcode()));
900          Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
901          Record.push_back(VE.getValueID(C->getOperand(0)));
902          AbbrevToUse = CONSTANTS_CE_CAST_Abbrev;
903        } else {
904          assert(CE->getNumOperands() == 2 && "Unknown constant expr!");
905          Code = bitc::CST_CODE_CE_BINOP;
906          Record.push_back(GetEncodedBinaryOpcode(CE->getOpcode()));
907          Record.push_back(VE.getValueID(C->getOperand(0)));
908          Record.push_back(VE.getValueID(C->getOperand(1)));
909          uint64_t Flags = GetOptimizationFlags(CE);
910          if (Flags != 0)
911            Record.push_back(Flags);
912        }
913        break;
914      case Instruction::GetElementPtr:
915        Code = bitc::CST_CODE_CE_GEP;
916        if (cast<GEPOperator>(C)->isInBounds())
917          Code = bitc::CST_CODE_CE_INBOUNDS_GEP;
918        for (unsigned i = 0, e = CE->getNumOperands(); i != e; ++i) {
919          Record.push_back(VE.getTypeID(C->getOperand(i)->getType()));
920          Record.push_back(VE.getValueID(C->getOperand(i)));
921        }
922        break;
923      case Instruction::Select:
924        Code = bitc::CST_CODE_CE_SELECT;
925        Record.push_back(VE.getValueID(C->getOperand(0)));
926        Record.push_back(VE.getValueID(C->getOperand(1)));
927        Record.push_back(VE.getValueID(C->getOperand(2)));
928        break;
929      case Instruction::ExtractElement:
930        Code = bitc::CST_CODE_CE_EXTRACTELT;
931        Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
932        Record.push_back(VE.getValueID(C->getOperand(0)));
933        Record.push_back(VE.getValueID(C->getOperand(1)));
934        break;
935      case Instruction::InsertElement:
936        Code = bitc::CST_CODE_CE_INSERTELT;
937        Record.push_back(VE.getValueID(C->getOperand(0)));
938        Record.push_back(VE.getValueID(C->getOperand(1)));
939        Record.push_back(VE.getValueID(C->getOperand(2)));
940        break;
941      case Instruction::ShuffleVector:
942        // If the return type and argument types are the same, this is a
943        // standard shufflevector instruction.  If the types are different,
944        // then the shuffle is widening or truncating the input vectors, and
945        // the argument type must also be encoded.
946        if (C->getType() == C->getOperand(0)->getType()) {
947          Code = bitc::CST_CODE_CE_SHUFFLEVEC;
948        } else {
949          Code = bitc::CST_CODE_CE_SHUFVEC_EX;
950          Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
951        }
952        Record.push_back(VE.getValueID(C->getOperand(0)));
953        Record.push_back(VE.getValueID(C->getOperand(1)));
954        Record.push_back(VE.getValueID(C->getOperand(2)));
955        break;
956      case Instruction::ICmp:
957      case Instruction::FCmp:
958        Code = bitc::CST_CODE_CE_CMP;
959        Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
960        Record.push_back(VE.getValueID(C->getOperand(0)));
961        Record.push_back(VE.getValueID(C->getOperand(1)));
962        Record.push_back(CE->getPredicate());
963        break;
964      }
965    } else if (const BlockAddress *BA = dyn_cast<BlockAddress>(C)) {
966      Code = bitc::CST_CODE_BLOCKADDRESS;
967      Record.push_back(VE.getTypeID(BA->getFunction()->getType()));
968      Record.push_back(VE.getValueID(BA->getFunction()));
969      Record.push_back(VE.getGlobalBasicBlockID(BA->getBasicBlock()));
970    } else {
971#ifndef NDEBUG
972      C->dump();
973#endif
974      llvm_unreachable("Unknown constant!");
975    }
976    Stream.EmitRecord(Code, Record, AbbrevToUse);
977    Record.clear();
978  }
979
980  Stream.ExitBlock();
981}
982
983static void WriteModuleConstants(const ValueEnumerator &VE,
984                                 BitstreamWriter &Stream) {
985  const ValueEnumerator::ValueList &Vals = VE.getValues();
986
987  // Find the first constant to emit, which is the first non-globalvalue value.
988  // We know globalvalues have been emitted by WriteModuleInfo.
989  for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
990    if (!isa<GlobalValue>(Vals[i].first)) {
991      WriteConstants(i, Vals.size(), VE, Stream, true);
992      return;
993    }
994  }
995}
996
997/// PushValueAndType - The file has to encode both the value and type id for
998/// many values, because we need to know what type to create for forward
999/// references.  However, most operands are not forward references, so this type
1000/// field is not needed.
1001///
1002/// This function adds V's value ID to Vals.  If the value ID is higher than the
1003/// instruction ID, then it is a forward reference, and it also includes the
1004/// type ID.
1005static bool PushValueAndType(const Value *V, unsigned InstID,
1006                             SmallVector<unsigned, 64> &Vals,
1007                             ValueEnumerator &VE) {
1008  unsigned ValID = VE.getValueID(V);
1009  Vals.push_back(ValID);
1010  if (ValID >= InstID) {
1011    Vals.push_back(VE.getTypeID(V->getType()));
1012    return true;
1013  }
1014  return false;
1015}
1016
1017/// WriteInstruction - Emit an instruction to the specified stream.
1018static void WriteInstruction(const Instruction &I, unsigned InstID,
1019                             ValueEnumerator &VE, BitstreamWriter &Stream,
1020                             SmallVector<unsigned, 64> &Vals) {
1021  unsigned Code = 0;
1022  unsigned AbbrevToUse = 0;
1023  VE.setInstructionID(&I);
1024  switch (I.getOpcode()) {
1025  default:
1026    if (Instruction::isCast(I.getOpcode())) {
1027      Code = bitc::FUNC_CODE_INST_CAST;
1028      if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1029        AbbrevToUse = FUNCTION_INST_CAST_ABBREV;
1030      Vals.push_back(VE.getTypeID(I.getType()));
1031      Vals.push_back(GetEncodedCastOpcode(I.getOpcode()));
1032    } else {
1033      assert(isa<BinaryOperator>(I) && "Unknown instruction!");
1034      Code = bitc::FUNC_CODE_INST_BINOP;
1035      if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1036        AbbrevToUse = FUNCTION_INST_BINOP_ABBREV;
1037      Vals.push_back(VE.getValueID(I.getOperand(1)));
1038      Vals.push_back(GetEncodedBinaryOpcode(I.getOpcode()));
1039      uint64_t Flags = GetOptimizationFlags(&I);
1040      if (Flags != 0) {
1041        if (AbbrevToUse == FUNCTION_INST_BINOP_ABBREV)
1042          AbbrevToUse = FUNCTION_INST_BINOP_FLAGS_ABBREV;
1043        Vals.push_back(Flags);
1044      }
1045    }
1046    break;
1047
1048  case Instruction::GetElementPtr:
1049    Code = bitc::FUNC_CODE_INST_GEP;
1050    if (cast<GEPOperator>(&I)->isInBounds())
1051      Code = bitc::FUNC_CODE_INST_INBOUNDS_GEP;
1052    for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1053      PushValueAndType(I.getOperand(i), InstID, Vals, VE);
1054    break;
1055  case Instruction::ExtractValue: {
1056    Code = bitc::FUNC_CODE_INST_EXTRACTVAL;
1057    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1058    const ExtractValueInst *EVI = cast<ExtractValueInst>(&I);
1059    for (const unsigned *i = EVI->idx_begin(), *e = EVI->idx_end(); i != e; ++i)
1060      Vals.push_back(*i);
1061    break;
1062  }
1063  case Instruction::InsertValue: {
1064    Code = bitc::FUNC_CODE_INST_INSERTVAL;
1065    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1066    PushValueAndType(I.getOperand(1), InstID, Vals, VE);
1067    const InsertValueInst *IVI = cast<InsertValueInst>(&I);
1068    for (const unsigned *i = IVI->idx_begin(), *e = IVI->idx_end(); i != e; ++i)
1069      Vals.push_back(*i);
1070    break;
1071  }
1072  case Instruction::Select:
1073    Code = bitc::FUNC_CODE_INST_VSELECT;
1074    PushValueAndType(I.getOperand(1), InstID, Vals, VE);
1075    Vals.push_back(VE.getValueID(I.getOperand(2)));
1076    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1077    break;
1078  case Instruction::ExtractElement:
1079    Code = bitc::FUNC_CODE_INST_EXTRACTELT;
1080    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1081    Vals.push_back(VE.getValueID(I.getOperand(1)));
1082    break;
1083  case Instruction::InsertElement:
1084    Code = bitc::FUNC_CODE_INST_INSERTELT;
1085    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1086    Vals.push_back(VE.getValueID(I.getOperand(1)));
1087    Vals.push_back(VE.getValueID(I.getOperand(2)));
1088    break;
1089  case Instruction::ShuffleVector:
1090    Code = bitc::FUNC_CODE_INST_SHUFFLEVEC;
1091    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1092    Vals.push_back(VE.getValueID(I.getOperand(1)));
1093    Vals.push_back(VE.getValueID(I.getOperand(2)));
1094    break;
1095  case Instruction::ICmp:
1096  case Instruction::FCmp:
1097    // compare returning Int1Ty or vector of Int1Ty
1098    Code = bitc::FUNC_CODE_INST_CMP2;
1099    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1100    Vals.push_back(VE.getValueID(I.getOperand(1)));
1101    Vals.push_back(cast<CmpInst>(I).getPredicate());
1102    break;
1103
1104  case Instruction::Ret:
1105    {
1106      Code = bitc::FUNC_CODE_INST_RET;
1107      unsigned NumOperands = I.getNumOperands();
1108      if (NumOperands == 0)
1109        AbbrevToUse = FUNCTION_INST_RET_VOID_ABBREV;
1110      else if (NumOperands == 1) {
1111        if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1112          AbbrevToUse = FUNCTION_INST_RET_VAL_ABBREV;
1113      } else {
1114        for (unsigned i = 0, e = NumOperands; i != e; ++i)
1115          PushValueAndType(I.getOperand(i), InstID, Vals, VE);
1116      }
1117    }
1118    break;
1119  case Instruction::Br:
1120    {
1121      Code = bitc::FUNC_CODE_INST_BR;
1122      BranchInst &II = cast<BranchInst>(I);
1123      Vals.push_back(VE.getValueID(II.getSuccessor(0)));
1124      if (II.isConditional()) {
1125        Vals.push_back(VE.getValueID(II.getSuccessor(1)));
1126        Vals.push_back(VE.getValueID(II.getCondition()));
1127      }
1128    }
1129    break;
1130  case Instruction::Switch:
1131    Code = bitc::FUNC_CODE_INST_SWITCH;
1132    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1133    for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1134      Vals.push_back(VE.getValueID(I.getOperand(i)));
1135    break;
1136  case Instruction::IndirectBr:
1137    Code = bitc::FUNC_CODE_INST_INDIRECTBR;
1138    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1139    for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1140      Vals.push_back(VE.getValueID(I.getOperand(i)));
1141    break;
1142
1143  case Instruction::Invoke: {
1144    const InvokeInst *II = cast<InvokeInst>(&I);
1145    const Value *Callee(II->getCalledValue());
1146    PointerType *PTy = cast<PointerType>(Callee->getType());
1147    FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1148    Code = bitc::FUNC_CODE_INST_INVOKE;
1149
1150    Vals.push_back(VE.getAttributeID(II->getAttributes()));
1151    Vals.push_back(II->getCallingConv());
1152    Vals.push_back(VE.getValueID(II->getNormalDest()));
1153    Vals.push_back(VE.getValueID(II->getUnwindDest()));
1154    PushValueAndType(Callee, InstID, Vals, VE);
1155
1156    // Emit value #'s for the fixed parameters.
1157    for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
1158      Vals.push_back(VE.getValueID(I.getOperand(i)));  // fixed param.
1159
1160    // Emit type/value pairs for varargs params.
1161    if (FTy->isVarArg()) {
1162      for (unsigned i = FTy->getNumParams(), e = I.getNumOperands()-3;
1163           i != e; ++i)
1164        PushValueAndType(I.getOperand(i), InstID, Vals, VE); // vararg
1165    }
1166    break;
1167  }
1168  case Instruction::Resume:
1169    Code = bitc::FUNC_CODE_INST_RESUME;
1170    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1171    break;
1172  case Instruction::Unreachable:
1173    Code = bitc::FUNC_CODE_INST_UNREACHABLE;
1174    AbbrevToUse = FUNCTION_INST_UNREACHABLE_ABBREV;
1175    break;
1176
1177  case Instruction::PHI: {
1178    const PHINode &PN = cast<PHINode>(I);
1179    Code = bitc::FUNC_CODE_INST_PHI;
1180    Vals.push_back(VE.getTypeID(PN.getType()));
1181    for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
1182      Vals.push_back(VE.getValueID(PN.getIncomingValue(i)));
1183      Vals.push_back(VE.getValueID(PN.getIncomingBlock(i)));
1184    }
1185    break;
1186  }
1187
1188  case Instruction::LandingPad: {
1189    const LandingPadInst &LP = cast<LandingPadInst>(I);
1190    Code = bitc::FUNC_CODE_INST_LANDINGPAD;
1191    Vals.push_back(VE.getTypeID(LP.getType()));
1192    PushValueAndType(LP.getPersonalityFn(), InstID, Vals, VE);
1193    Vals.push_back(LP.isCleanup());
1194    Vals.push_back(LP.getNumClauses());
1195    for (unsigned I = 0, E = LP.getNumClauses(); I != E; ++I) {
1196      if (LP.isCatch(I))
1197        Vals.push_back(LandingPadInst::Catch);
1198      else
1199        Vals.push_back(LandingPadInst::Filter);
1200      PushValueAndType(LP.getClause(I), InstID, Vals, VE);
1201    }
1202    break;
1203  }
1204
1205  case Instruction::Alloca:
1206    Code = bitc::FUNC_CODE_INST_ALLOCA;
1207    Vals.push_back(VE.getTypeID(I.getType()));
1208    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1209    Vals.push_back(VE.getValueID(I.getOperand(0))); // size.
1210    Vals.push_back(Log2_32(cast<AllocaInst>(I).getAlignment())+1);
1211    break;
1212
1213  case Instruction::Load:
1214    if (cast<LoadInst>(I).isAtomic()) {
1215      Code = bitc::FUNC_CODE_INST_LOADATOMIC;
1216      PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1217    } else {
1218      Code = bitc::FUNC_CODE_INST_LOAD;
1219      if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))  // ptr
1220        AbbrevToUse = FUNCTION_INST_LOAD_ABBREV;
1221    }
1222    Vals.push_back(Log2_32(cast<LoadInst>(I).getAlignment())+1);
1223    Vals.push_back(cast<LoadInst>(I).isVolatile());
1224    if (cast<LoadInst>(I).isAtomic()) {
1225      Vals.push_back(GetEncodedOrdering(cast<LoadInst>(I).getOrdering()));
1226      Vals.push_back(GetEncodedSynchScope(cast<LoadInst>(I).getSynchScope()));
1227    }
1228    break;
1229  case Instruction::Store:
1230    if (cast<StoreInst>(I).isAtomic())
1231      Code = bitc::FUNC_CODE_INST_STOREATOMIC;
1232    else
1233      Code = bitc::FUNC_CODE_INST_STORE;
1234    PushValueAndType(I.getOperand(1), InstID, Vals, VE);  // ptrty + ptr
1235    Vals.push_back(VE.getValueID(I.getOperand(0)));       // val.
1236    Vals.push_back(Log2_32(cast<StoreInst>(I).getAlignment())+1);
1237    Vals.push_back(cast<StoreInst>(I).isVolatile());
1238    if (cast<StoreInst>(I).isAtomic()) {
1239      Vals.push_back(GetEncodedOrdering(cast<StoreInst>(I).getOrdering()));
1240      Vals.push_back(GetEncodedSynchScope(cast<StoreInst>(I).getSynchScope()));
1241    }
1242    break;
1243  case Instruction::AtomicCmpXchg:
1244    Code = bitc::FUNC_CODE_INST_CMPXCHG;
1245    PushValueAndType(I.getOperand(0), InstID, Vals, VE);  // ptrty + ptr
1246    Vals.push_back(VE.getValueID(I.getOperand(1)));       // cmp.
1247    Vals.push_back(VE.getValueID(I.getOperand(2)));       // newval.
1248    Vals.push_back(cast<AtomicCmpXchgInst>(I).isVolatile());
1249    Vals.push_back(GetEncodedOrdering(
1250                     cast<AtomicCmpXchgInst>(I).getOrdering()));
1251    Vals.push_back(GetEncodedSynchScope(
1252                     cast<AtomicCmpXchgInst>(I).getSynchScope()));
1253    break;
1254  case Instruction::AtomicRMW:
1255    Code = bitc::FUNC_CODE_INST_ATOMICRMW;
1256    PushValueAndType(I.getOperand(0), InstID, Vals, VE);  // ptrty + ptr
1257    Vals.push_back(VE.getValueID(I.getOperand(1)));       // val.
1258    Vals.push_back(GetEncodedRMWOperation(
1259                     cast<AtomicRMWInst>(I).getOperation()));
1260    Vals.push_back(cast<AtomicRMWInst>(I).isVolatile());
1261    Vals.push_back(GetEncodedOrdering(cast<AtomicRMWInst>(I).getOrdering()));
1262    Vals.push_back(GetEncodedSynchScope(
1263                     cast<AtomicRMWInst>(I).getSynchScope()));
1264    break;
1265  case Instruction::Fence:
1266    Code = bitc::FUNC_CODE_INST_FENCE;
1267    Vals.push_back(GetEncodedOrdering(cast<FenceInst>(I).getOrdering()));
1268    Vals.push_back(GetEncodedSynchScope(cast<FenceInst>(I).getSynchScope()));
1269    break;
1270  case Instruction::Call: {
1271    const CallInst &CI = cast<CallInst>(I);
1272    PointerType *PTy = cast<PointerType>(CI.getCalledValue()->getType());
1273    FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1274
1275    Code = bitc::FUNC_CODE_INST_CALL;
1276
1277    Vals.push_back(VE.getAttributeID(CI.getAttributes()));
1278    Vals.push_back((CI.getCallingConv() << 1) | unsigned(CI.isTailCall()));
1279    PushValueAndType(CI.getCalledValue(), InstID, Vals, VE);  // Callee
1280
1281    // Emit value #'s for the fixed parameters.
1282    for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
1283      Vals.push_back(VE.getValueID(CI.getArgOperand(i)));  // fixed param.
1284
1285    // Emit type/value pairs for varargs params.
1286    if (FTy->isVarArg()) {
1287      for (unsigned i = FTy->getNumParams(), e = CI.getNumArgOperands();
1288           i != e; ++i)
1289        PushValueAndType(CI.getArgOperand(i), InstID, Vals, VE);  // varargs
1290    }
1291    break;
1292  }
1293  case Instruction::VAArg:
1294    Code = bitc::FUNC_CODE_INST_VAARG;
1295    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));   // valistty
1296    Vals.push_back(VE.getValueID(I.getOperand(0))); // valist.
1297    Vals.push_back(VE.getTypeID(I.getType())); // restype.
1298    break;
1299  }
1300
1301  Stream.EmitRecord(Code, Vals, AbbrevToUse);
1302  Vals.clear();
1303}
1304
1305// Emit names for globals/functions etc.
1306static void WriteValueSymbolTable(const ValueSymbolTable &VST,
1307                                  const ValueEnumerator &VE,
1308                                  BitstreamWriter &Stream) {
1309  if (VST.empty()) return;
1310  Stream.EnterSubblock(bitc::VALUE_SYMTAB_BLOCK_ID, 4);
1311
1312  // FIXME: Set up the abbrev, we know how many values there are!
1313  // FIXME: We know if the type names can use 7-bit ascii.
1314  SmallVector<unsigned, 64> NameVals;
1315
1316  for (ValueSymbolTable::const_iterator SI = VST.begin(), SE = VST.end();
1317       SI != SE; ++SI) {
1318
1319    const ValueName &Name = *SI;
1320
1321    // Figure out the encoding to use for the name.
1322    bool is7Bit = true;
1323    bool isChar6 = true;
1324    for (const char *C = Name.getKeyData(), *E = C+Name.getKeyLength();
1325         C != E; ++C) {
1326      if (isChar6)
1327        isChar6 = BitCodeAbbrevOp::isChar6(*C);
1328      if ((unsigned char)*C & 128) {
1329        is7Bit = false;
1330        break;  // don't bother scanning the rest.
1331      }
1332    }
1333
1334    unsigned AbbrevToUse = VST_ENTRY_8_ABBREV;
1335
1336    // VST_ENTRY:   [valueid, namechar x N]
1337    // VST_BBENTRY: [bbid, namechar x N]
1338    unsigned Code;
1339    if (isa<BasicBlock>(SI->getValue())) {
1340      Code = bitc::VST_CODE_BBENTRY;
1341      if (isChar6)
1342        AbbrevToUse = VST_BBENTRY_6_ABBREV;
1343    } else {
1344      Code = bitc::VST_CODE_ENTRY;
1345      if (isChar6)
1346        AbbrevToUse = VST_ENTRY_6_ABBREV;
1347      else if (is7Bit)
1348        AbbrevToUse = VST_ENTRY_7_ABBREV;
1349    }
1350
1351    NameVals.push_back(VE.getValueID(SI->getValue()));
1352    for (const char *P = Name.getKeyData(),
1353         *E = Name.getKeyData()+Name.getKeyLength(); P != E; ++P)
1354      NameVals.push_back((unsigned char)*P);
1355
1356    // Emit the finished record.
1357    Stream.EmitRecord(Code, NameVals, AbbrevToUse);
1358    NameVals.clear();
1359  }
1360  Stream.ExitBlock();
1361}
1362
1363/// WriteFunction - Emit a function body to the module stream.
1364static void WriteFunction(const Function &F, ValueEnumerator &VE,
1365                          BitstreamWriter &Stream) {
1366  Stream.EnterSubblock(bitc::FUNCTION_BLOCK_ID, 4);
1367  VE.incorporateFunction(F);
1368
1369  SmallVector<unsigned, 64> Vals;
1370
1371  // Emit the number of basic blocks, so the reader can create them ahead of
1372  // time.
1373  Vals.push_back(VE.getBasicBlocks().size());
1374  Stream.EmitRecord(bitc::FUNC_CODE_DECLAREBLOCKS, Vals);
1375  Vals.clear();
1376
1377  // If there are function-local constants, emit them now.
1378  unsigned CstStart, CstEnd;
1379  VE.getFunctionConstantRange(CstStart, CstEnd);
1380  WriteConstants(CstStart, CstEnd, VE, Stream, false);
1381
1382  // If there is function-local metadata, emit it now.
1383  WriteFunctionLocalMetadata(F, VE, Stream);
1384
1385  // Keep a running idea of what the instruction ID is.
1386  unsigned InstID = CstEnd;
1387
1388  bool NeedsMetadataAttachment = false;
1389
1390  DebugLoc LastDL;
1391
1392  // Finally, emit all the instructions, in order.
1393  for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
1394    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
1395         I != E; ++I) {
1396      WriteInstruction(*I, InstID, VE, Stream, Vals);
1397
1398      if (!I->getType()->isVoidTy())
1399        ++InstID;
1400
1401      // If the instruction has metadata, write a metadata attachment later.
1402      NeedsMetadataAttachment |= I->hasMetadataOtherThanDebugLoc();
1403
1404      // If the instruction has a debug location, emit it.
1405      DebugLoc DL = I->getDebugLoc();
1406      if (DL.isUnknown()) {
1407        // nothing todo.
1408      } else if (DL == LastDL) {
1409        // Just repeat the same debug loc as last time.
1410        Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC_AGAIN, Vals);
1411      } else {
1412        MDNode *Scope, *IA;
1413        DL.getScopeAndInlinedAt(Scope, IA, I->getContext());
1414
1415        Vals.push_back(DL.getLine());
1416        Vals.push_back(DL.getCol());
1417        Vals.push_back(Scope ? VE.getValueID(Scope)+1 : 0);
1418        Vals.push_back(IA ? VE.getValueID(IA)+1 : 0);
1419        Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC, Vals);
1420        Vals.clear();
1421
1422        LastDL = DL;
1423      }
1424    }
1425
1426  // Emit names for all the instructions etc.
1427  WriteValueSymbolTable(F.getValueSymbolTable(), VE, Stream);
1428
1429  if (NeedsMetadataAttachment)
1430    WriteMetadataAttachment(F, VE, Stream);
1431  VE.purgeFunction();
1432  Stream.ExitBlock();
1433}
1434
1435// Emit blockinfo, which defines the standard abbreviations etc.
1436static void WriteBlockInfo(const ValueEnumerator &VE, BitstreamWriter &Stream) {
1437  // We only want to emit block info records for blocks that have multiple
1438  // instances: CONSTANTS_BLOCK, FUNCTION_BLOCK and VALUE_SYMTAB_BLOCK.  Other
1439  // blocks can defined their abbrevs inline.
1440  Stream.EnterBlockInfoBlock(2);
1441
1442  { // 8-bit fixed-width VST_ENTRY/VST_BBENTRY strings.
1443    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1444    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3));
1445    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1446    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1447    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
1448    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1449                                   Abbv) != VST_ENTRY_8_ABBREV)
1450      llvm_unreachable("Unexpected abbrev ordering!");
1451  }
1452
1453  { // 7-bit fixed width VST_ENTRY strings.
1454    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1455    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1456    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1457    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1458    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
1459    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1460                                   Abbv) != VST_ENTRY_7_ABBREV)
1461      llvm_unreachable("Unexpected abbrev ordering!");
1462  }
1463  { // 6-bit char6 VST_ENTRY strings.
1464    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1465    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1466    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1467    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1468    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1469    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1470                                   Abbv) != VST_ENTRY_6_ABBREV)
1471      llvm_unreachable("Unexpected abbrev ordering!");
1472  }
1473  { // 6-bit char6 VST_BBENTRY strings.
1474    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1475    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_BBENTRY));
1476    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1477    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1478    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1479    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1480                                   Abbv) != VST_BBENTRY_6_ABBREV)
1481      llvm_unreachable("Unexpected abbrev ordering!");
1482  }
1483
1484
1485
1486  { // SETTYPE abbrev for CONSTANTS_BLOCK.
1487    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1488    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_SETTYPE));
1489    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1490                              Log2_32_Ceil(VE.getTypes().size()+1)));
1491    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1492                                   Abbv) != CONSTANTS_SETTYPE_ABBREV)
1493      llvm_unreachable("Unexpected abbrev ordering!");
1494  }
1495
1496  { // INTEGER abbrev for CONSTANTS_BLOCK.
1497    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1498    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_INTEGER));
1499    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1500    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1501                                   Abbv) != CONSTANTS_INTEGER_ABBREV)
1502      llvm_unreachable("Unexpected abbrev ordering!");
1503  }
1504
1505  { // CE_CAST abbrev for CONSTANTS_BLOCK.
1506    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1507    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CE_CAST));
1508    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // cast opc
1509    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // typeid
1510                              Log2_32_Ceil(VE.getTypes().size()+1)));
1511    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));    // value id
1512
1513    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1514                                   Abbv) != CONSTANTS_CE_CAST_Abbrev)
1515      llvm_unreachable("Unexpected abbrev ordering!");
1516  }
1517  { // NULL abbrev for CONSTANTS_BLOCK.
1518    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1519    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_NULL));
1520    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1521                                   Abbv) != CONSTANTS_NULL_Abbrev)
1522      llvm_unreachable("Unexpected abbrev ordering!");
1523  }
1524
1525  // FIXME: This should only use space for first class types!
1526
1527  { // INST_LOAD abbrev for FUNCTION_BLOCK.
1528    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1529    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_LOAD));
1530    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Ptr
1531    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4)); // Align
1532    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // volatile
1533    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1534                                   Abbv) != FUNCTION_INST_LOAD_ABBREV)
1535      llvm_unreachable("Unexpected abbrev ordering!");
1536  }
1537  { // INST_BINOP abbrev for FUNCTION_BLOCK.
1538    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1539    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1540    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1541    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1542    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1543    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1544                                   Abbv) != FUNCTION_INST_BINOP_ABBREV)
1545      llvm_unreachable("Unexpected abbrev ordering!");
1546  }
1547  { // INST_BINOP_FLAGS abbrev for FUNCTION_BLOCK.
1548    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1549    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1550    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1551    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1552    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1553    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7)); // flags
1554    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1555                                   Abbv) != FUNCTION_INST_BINOP_FLAGS_ABBREV)
1556      llvm_unreachable("Unexpected abbrev ordering!");
1557  }
1558  { // INST_CAST abbrev for FUNCTION_BLOCK.
1559    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1560    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_CAST));
1561    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));    // OpVal
1562    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // dest ty
1563                              Log2_32_Ceil(VE.getTypes().size()+1)));
1564    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // opc
1565    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1566                                   Abbv) != FUNCTION_INST_CAST_ABBREV)
1567      llvm_unreachable("Unexpected abbrev ordering!");
1568  }
1569
1570  { // INST_RET abbrev for FUNCTION_BLOCK.
1571    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1572    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1573    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1574                                   Abbv) != FUNCTION_INST_RET_VOID_ABBREV)
1575      llvm_unreachable("Unexpected abbrev ordering!");
1576  }
1577  { // INST_RET abbrev for FUNCTION_BLOCK.
1578    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1579    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1580    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ValID
1581    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1582                                   Abbv) != FUNCTION_INST_RET_VAL_ABBREV)
1583      llvm_unreachable("Unexpected abbrev ordering!");
1584  }
1585  { // INST_UNREACHABLE abbrev for FUNCTION_BLOCK.
1586    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1587    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_UNREACHABLE));
1588    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1589                                   Abbv) != FUNCTION_INST_UNREACHABLE_ABBREV)
1590      llvm_unreachable("Unexpected abbrev ordering!");
1591  }
1592
1593  Stream.ExitBlock();
1594}
1595
1596
1597/// WriteModule - Emit the specified module to the bitstream.
1598static void WriteModule(const Module *M, BitstreamWriter &Stream) {
1599  Stream.EnterSubblock(bitc::MODULE_BLOCK_ID, 3);
1600
1601  // Emit the version number if it is non-zero.
1602  if (CurVersion) {
1603    SmallVector<unsigned, 1> Vals;
1604    Vals.push_back(CurVersion);
1605    Stream.EmitRecord(bitc::MODULE_CODE_VERSION, Vals);
1606  }
1607
1608  // Analyze the module, enumerating globals, functions, etc.
1609  ValueEnumerator VE(M);
1610
1611  // Emit blockinfo, which defines the standard abbreviations etc.
1612  WriteBlockInfo(VE, Stream);
1613
1614  // Emit information about parameter attributes.
1615  WriteAttributeTable(VE, Stream);
1616
1617  // Emit information describing all of the types in the module.
1618  WriteTypeTable(VE, Stream);
1619
1620  // Emit top-level description of module, including target triple, inline asm,
1621  // descriptors for global variables, and function prototype info.
1622  WriteModuleInfo(M, VE, Stream);
1623
1624  // Emit constants.
1625  WriteModuleConstants(VE, Stream);
1626
1627  // Emit metadata.
1628  WriteModuleMetadata(M, VE, Stream);
1629
1630  // Emit function bodies.
1631  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F)
1632    if (!F->isDeclaration())
1633      WriteFunction(*F, VE, Stream);
1634
1635  // Emit metadata.
1636  WriteModuleMetadataStore(M, Stream);
1637
1638  // Emit names for globals/functions etc.
1639  WriteValueSymbolTable(M->getValueSymbolTable(), VE, Stream);
1640
1641  Stream.ExitBlock();
1642}
1643
1644/// EmitDarwinBCHeader - If generating a bc file on darwin, we have to emit a
1645/// header and trailer to make it compatible with the system archiver.  To do
1646/// this we emit the following header, and then emit a trailer that pads the
1647/// file out to be a multiple of 16 bytes.
1648///
1649/// struct bc_header {
1650///   uint32_t Magic;         // 0x0B17C0DE
1651///   uint32_t Version;       // Version, currently always 0.
1652///   uint32_t BitcodeOffset; // Offset to traditional bitcode file.
1653///   uint32_t BitcodeSize;   // Size of traditional bitcode file.
1654///   uint32_t CPUType;       // CPU specifier.
1655///   ... potentially more later ...
1656/// };
1657enum {
1658  DarwinBCSizeFieldOffset = 3*4, // Offset to bitcode_size.
1659  DarwinBCHeaderSize = 5*4
1660};
1661
1662static void WriteInt32ToBuffer(uint32_t Value, SmallVectorImpl<char> &Buffer,
1663                               uint32_t &Position) {
1664  Buffer[Position + 0] = (unsigned char) (Value >>  0);
1665  Buffer[Position + 1] = (unsigned char) (Value >>  8);
1666  Buffer[Position + 2] = (unsigned char) (Value >> 16);
1667  Buffer[Position + 3] = (unsigned char) (Value >> 24);
1668  Position += 4;
1669}
1670
1671static void EmitDarwinBCHeaderAndTrailer(SmallVectorImpl<char> &Buffer,
1672                                         const Triple &TT) {
1673  unsigned CPUType = ~0U;
1674
1675  // Match x86_64-*, i[3-9]86-*, powerpc-*, powerpc64-*, arm-*, thumb-*,
1676  // armv[0-9]-*, thumbv[0-9]-*, armv5te-*, or armv6t2-*. The CPUType is a magic
1677  // number from /usr/include/mach/machine.h.  It is ok to reproduce the
1678  // specific constants here because they are implicitly part of the Darwin ABI.
1679  enum {
1680    DARWIN_CPU_ARCH_ABI64      = 0x01000000,
1681    DARWIN_CPU_TYPE_X86        = 7,
1682    DARWIN_CPU_TYPE_ARM        = 12,
1683    DARWIN_CPU_TYPE_POWERPC    = 18
1684  };
1685
1686  Triple::ArchType Arch = TT.getArch();
1687  if (Arch == Triple::x86_64)
1688    CPUType = DARWIN_CPU_TYPE_X86 | DARWIN_CPU_ARCH_ABI64;
1689  else if (Arch == Triple::x86)
1690    CPUType = DARWIN_CPU_TYPE_X86;
1691  else if (Arch == Triple::ppc)
1692    CPUType = DARWIN_CPU_TYPE_POWERPC;
1693  else if (Arch == Triple::ppc64)
1694    CPUType = DARWIN_CPU_TYPE_POWERPC | DARWIN_CPU_ARCH_ABI64;
1695  else if (Arch == Triple::arm || Arch == Triple::thumb)
1696    CPUType = DARWIN_CPU_TYPE_ARM;
1697
1698  // Traditional Bitcode starts after header.
1699  assert(Buffer.size() >= DarwinBCHeaderSize &&
1700         "Expected header size to be reserved");
1701  unsigned BCOffset = DarwinBCHeaderSize;
1702  unsigned BCSize = Buffer.size()-DarwinBCHeaderSize;
1703
1704  // Write the magic and version.
1705  unsigned Position = 0;
1706  WriteInt32ToBuffer(0x0B17C0DE , Buffer, Position);
1707  WriteInt32ToBuffer(0          , Buffer, Position); // Version.
1708  WriteInt32ToBuffer(BCOffset   , Buffer, Position);
1709  WriteInt32ToBuffer(BCSize     , Buffer, Position);
1710  WriteInt32ToBuffer(CPUType    , Buffer, Position);
1711
1712  // If the file is not a multiple of 16 bytes, insert dummy padding.
1713  while (Buffer.size() & 15)
1714    Buffer.push_back(0);
1715}
1716
1717/// WriteBitcodeToFile - Write the specified module to the specified output
1718/// stream.
1719void llvm_2_9_func::WriteBitcodeToFile(const Module *M, raw_ostream &Out) {
1720  SmallVector<char, 1024> Buffer;
1721  Buffer.reserve(256*1024);
1722
1723  // If this is darwin or another generic macho target, reserve space for the
1724  // header.
1725  Triple TT(M->getTargetTriple());
1726  if (TT.isOSDarwin())
1727    Buffer.insert(Buffer.begin(), DarwinBCHeaderSize, 0);
1728
1729  // Emit the module into the buffer.
1730  {
1731    BitstreamWriter Stream(Buffer);
1732
1733    // Emit the file header.
1734    Stream.Emit((unsigned)'B', 8);
1735    Stream.Emit((unsigned)'C', 8);
1736    Stream.Emit(0x0, 4);
1737    Stream.Emit(0xC, 4);
1738    Stream.Emit(0xE, 4);
1739    Stream.Emit(0xD, 4);
1740
1741    // Emit the module.
1742    WriteModule(M, Stream);
1743  }
1744
1745  if (TT.isOSDarwin())
1746    EmitDarwinBCHeaderAndTrailer(Buffer, TT);
1747
1748  // Write the generated bitstream to "Out".
1749  Out.write((char*)&Buffer.front(), Buffer.size());
1750}
1751