BitcodeWriter.cpp revision 073d48da50a1b68ae2d1a69c44d5cc18fd9e41dc 
1//===--- Bitcode/Writer/BitcodeWriter.cpp - Bitcode Writer ----------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file was developed by Chris Lattner and is distributed under
6// the University of Illinois Open Source License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// Bitcode writer implementation.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/Bitcode/ReaderWriter.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/ParameterAttributes.h"
24#include "llvm/TypeSymbolTable.h"
25#include "llvm/ValueSymbolTable.h"
26#include "llvm/Support/MathExtras.h"
27using namespace llvm;
28
29/// These are manifest constants used by the bitcode writer. They do not need to
30/// be kept in sync with the reader, but need to be consistent within this file.
31enum {
32  CurVersion = 0,
33
34  // VALUE_SYMTAB_BLOCK abbrev id's.
35  VST_ENTRY_8_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
36  VST_ENTRY_7_ABBREV,
37  VST_ENTRY_6_ABBREV,
38  VST_BBENTRY_6_ABBREV,
39
40  // CONSTANTS_BLOCK abbrev id's.
41  CONSTANTS_SETTYPE_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
42  CONSTANTS_INTEGER_ABBREV,
43  CONSTANTS_CE_CAST_Abbrev,
44  CONSTANTS_NULL_Abbrev,
45
46  // FUNCTION_BLOCK abbrev id's.
47  FUNCTION_INST_LOAD_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
48  FUNCTION_INST_BINOP_ABBREV,
49  FUNCTION_INST_CAST_ABBREV,
50  FUNCTION_INST_RET_VOID_ABBREV,
51  FUNCTION_INST_RET_VAL_ABBREV,
52  FUNCTION_INST_UNREACHABLE_ABBREV
53};
54
55
56static unsigned GetEncodedCastOpcode(unsigned Opcode) {
57  switch (Opcode) {
58  default: assert(0 && "Unknown cast instruction!");
59  case Instruction::Trunc   : return bitc::CAST_TRUNC;
60  case Instruction::ZExt    : return bitc::CAST_ZEXT;
61  case Instruction::SExt    : return bitc::CAST_SEXT;
62  case Instruction::FPToUI  : return bitc::CAST_FPTOUI;
63  case Instruction::FPToSI  : return bitc::CAST_FPTOSI;
64  case Instruction::UIToFP  : return bitc::CAST_UITOFP;
65  case Instruction::SIToFP  : return bitc::CAST_SITOFP;
66  case Instruction::FPTrunc : return bitc::CAST_FPTRUNC;
67  case Instruction::FPExt   : return bitc::CAST_FPEXT;
68  case Instruction::PtrToInt: return bitc::CAST_PTRTOINT;
69  case Instruction::IntToPtr: return bitc::CAST_INTTOPTR;
70  case Instruction::BitCast : return bitc::CAST_BITCAST;
71  }
72}
73
74static unsigned GetEncodedBinaryOpcode(unsigned Opcode) {
75  switch (Opcode) {
76  default: assert(0 && "Unknown binary instruction!");
77  case Instruction::Add:  return bitc::BINOP_ADD;
78  case Instruction::Sub:  return bitc::BINOP_SUB;
79  case Instruction::Mul:  return bitc::BINOP_MUL;
80  case Instruction::UDiv: return bitc::BINOP_UDIV;
81  case Instruction::FDiv:
82  case Instruction::SDiv: return bitc::BINOP_SDIV;
83  case Instruction::URem: return bitc::BINOP_UREM;
84  case Instruction::FRem:
85  case Instruction::SRem: return bitc::BINOP_SREM;
86  case Instruction::Shl:  return bitc::BINOP_SHL;
87  case Instruction::LShr: return bitc::BINOP_LSHR;
88  case Instruction::AShr: return bitc::BINOP_ASHR;
89  case Instruction::And:  return bitc::BINOP_AND;
90  case Instruction::Or:   return bitc::BINOP_OR;
91  case Instruction::Xor:  return bitc::BINOP_XOR;
92  }
93}
94
95
96
97static void WriteStringRecord(unsigned Code, const std::string &Str,
98                              unsigned AbbrevToUse, BitstreamWriter &Stream) {
99  SmallVector<unsigned, 64> Vals;
100
101  // Code: [strchar x N]
102  for (unsigned i = 0, e = Str.size(); i != e; ++i)
103    Vals.push_back(Str[i]);
104
105  // Emit the finished record.
106  Stream.EmitRecord(Code, Vals, AbbrevToUse);
107}
108
109// Emit information about parameter attributes.
110static void WriteParamAttrTable(const ValueEnumerator &VE,
111                                BitstreamWriter &Stream) {
112  const std::vector<const ParamAttrsList*> &Attrs = VE.getParamAttrs();
113  if (Attrs.empty()) return;
114
115  Stream.EnterSubblock(bitc::PARAMATTR_BLOCK_ID, 3);
116
117  SmallVector<uint64_t, 64> Record;
118  for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
119    const ParamAttrsList *A = Attrs[i];
120    for (unsigned op = 0, e = A->size(); op != e; ++op) {
121      Record.push_back(A->getParamIndex(op));
122      Record.push_back(A->getParamAttrsAtIndex(op));
123    }
124
125    Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY, Record);
126    Record.clear();
127  }
128
129  Stream.ExitBlock();
130}
131
132/// WriteTypeTable - Write out the type table for a module.
133static void WriteTypeTable(const ValueEnumerator &VE, BitstreamWriter &Stream) {
134  const ValueEnumerator::TypeList &TypeList = VE.getTypes();
135
136  Stream.EnterSubblock(bitc::TYPE_BLOCK_ID, 4 /*count from # abbrevs */);
137  SmallVector<uint64_t, 64> TypeVals;
138
139  // Abbrev for TYPE_CODE_POINTER.
140  BitCodeAbbrev *Abbv = new BitCodeAbbrev();
141  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_POINTER));
142  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
143                            Log2_32_Ceil(VE.getTypes().size()+1)));
144  unsigned PtrAbbrev = Stream.EmitAbbrev(Abbv);
145
146  // Abbrev for TYPE_CODE_FUNCTION.
147  Abbv = new BitCodeAbbrev();
148  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_FUNCTION));
149  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // isvararg
150  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
151                            Log2_32_Ceil(VE.getParamAttrs().size()+1)));
152  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
153  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
154                            Log2_32_Ceil(VE.getTypes().size()+1)));
155  unsigned FunctionAbbrev = Stream.EmitAbbrev(Abbv);
156
157  // Abbrev for TYPE_CODE_STRUCT.
158  Abbv = new BitCodeAbbrev();
159  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT));
160  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // ispacked
161  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
162  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
163                            Log2_32_Ceil(VE.getTypes().size()+1)));
164  unsigned StructAbbrev = Stream.EmitAbbrev(Abbv);
165
166  // Abbrev for TYPE_CODE_ARRAY.
167  Abbv = new BitCodeAbbrev();
168  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_ARRAY));
169  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // size
170  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
171                            Log2_32_Ceil(VE.getTypes().size()+1)));
172  unsigned ArrayAbbrev = Stream.EmitAbbrev(Abbv);
173
174  // Emit an entry count so the reader can reserve space.
175  TypeVals.push_back(TypeList.size());
176  Stream.EmitRecord(bitc::TYPE_CODE_NUMENTRY, TypeVals);
177  TypeVals.clear();
178
179  // Loop over all of the types, emitting each in turn.
180  for (unsigned i = 0, e = TypeList.size(); i != e; ++i) {
181    const Type *T = TypeList[i].first;
182    int AbbrevToUse = 0;
183    unsigned Code = 0;
184
185    switch (T->getTypeID()) {
186    default: assert(0 && "Unknown type!");
187    case Type::VoidTyID:   Code = bitc::TYPE_CODE_VOID;   break;
188    case Type::FloatTyID:  Code = bitc::TYPE_CODE_FLOAT;  break;
189    case Type::DoubleTyID: Code = bitc::TYPE_CODE_DOUBLE; break;
190    case Type::X86_FP80TyID: Code = bitc::TYPE_CODE_X86_FP80; break;
191    case Type::FP128TyID: Code = bitc::TYPE_CODE_FP128; break;
192    case Type::PPC_FP128TyID: Code = bitc::TYPE_CODE_PPC_FP128; break;
193    case Type::LabelTyID:  Code = bitc::TYPE_CODE_LABEL;  break;
194    case Type::OpaqueTyID: Code = bitc::TYPE_CODE_OPAQUE; break;
195    case Type::IntegerTyID:
196      // INTEGER: [width]
197      Code = bitc::TYPE_CODE_INTEGER;
198      TypeVals.push_back(cast<IntegerType>(T)->getBitWidth());
199      break;
200    case Type::PointerTyID:
201      // POINTER: [pointee type]
202      Code = bitc::TYPE_CODE_POINTER;
203      TypeVals.push_back(VE.getTypeID(cast<PointerType>(T)->getElementType()));
204      AbbrevToUse = PtrAbbrev;
205      break;
206
207    case Type::FunctionTyID: {
208      const FunctionType *FT = cast<FunctionType>(T);
209      // FUNCTION: [isvararg, attrid, retty, paramty x N]
210      Code = bitc::TYPE_CODE_FUNCTION;
211      TypeVals.push_back(FT->isVarArg());
212      TypeVals.push_back(VE.getParamAttrID(FT->getParamAttrs()));
213      TypeVals.push_back(VE.getTypeID(FT->getReturnType()));
214      for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i)
215        TypeVals.push_back(VE.getTypeID(FT->getParamType(i)));
216      AbbrevToUse = FunctionAbbrev;
217      break;
218    }
219    case Type::StructTyID: {
220      const StructType *ST = cast<StructType>(T);
221      // STRUCT: [ispacked, eltty x N]
222      Code = bitc::TYPE_CODE_STRUCT;
223      TypeVals.push_back(ST->isPacked());
224      // Output all of the element types.
225      for (StructType::element_iterator I = ST->element_begin(),
226           E = ST->element_end(); I != E; ++I)
227        TypeVals.push_back(VE.getTypeID(*I));
228      AbbrevToUse = StructAbbrev;
229      break;
230    }
231    case Type::ArrayTyID: {
232      const ArrayType *AT = cast<ArrayType>(T);
233      // ARRAY: [numelts, eltty]
234      Code = bitc::TYPE_CODE_ARRAY;
235      TypeVals.push_back(AT->getNumElements());
236      TypeVals.push_back(VE.getTypeID(AT->getElementType()));
237      AbbrevToUse = ArrayAbbrev;
238      break;
239    }
240    case Type::VectorTyID: {
241      const VectorType *VT = cast<VectorType>(T);
242      // VECTOR [numelts, eltty]
243      Code = bitc::TYPE_CODE_VECTOR;
244      TypeVals.push_back(VT->getNumElements());
245      TypeVals.push_back(VE.getTypeID(VT->getElementType()));
246      break;
247    }
248    }
249
250    // Emit the finished record.
251    Stream.EmitRecord(Code, TypeVals, AbbrevToUse);
252    TypeVals.clear();
253  }
254
255  Stream.ExitBlock();
256}
257
258static unsigned getEncodedLinkage(const GlobalValue *GV) {
259  switch (GV->getLinkage()) {
260  default: assert(0 && "Invalid linkage!");
261  case GlobalValue::GhostLinkage:  // Map ghost linkage onto external.
262  case GlobalValue::ExternalLinkage:     return 0;
263  case GlobalValue::WeakLinkage:         return 1;
264  case GlobalValue::AppendingLinkage:    return 2;
265  case GlobalValue::InternalLinkage:     return 3;
266  case GlobalValue::LinkOnceLinkage:     return 4;
267  case GlobalValue::DLLImportLinkage:    return 5;
268  case GlobalValue::DLLExportLinkage:    return 6;
269  case GlobalValue::ExternalWeakLinkage: return 7;
270  }
271}
272
273static unsigned getEncodedVisibility(const GlobalValue *GV) {
274  switch (GV->getVisibility()) {
275  default: assert(0 && "Invalid visibility!");
276  case GlobalValue::DefaultVisibility:   return 0;
277  case GlobalValue::HiddenVisibility:    return 1;
278  case GlobalValue::ProtectedVisibility: return 2;
279  }
280}
281
282// Emit top-level description of module, including target triple, inline asm,
283// descriptors for global variables, and function prototype info.
284static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
285                            BitstreamWriter &Stream) {
286  // Emit the list of dependent libraries for the Module.
287  for (Module::lib_iterator I = M->lib_begin(), E = M->lib_end(); I != E; ++I)
288    WriteStringRecord(bitc::MODULE_CODE_DEPLIB, *I, 0/*TODO*/, Stream);
289
290  // Emit various pieces of data attached to a module.
291  if (!M->getTargetTriple().empty())
292    WriteStringRecord(bitc::MODULE_CODE_TRIPLE, M->getTargetTriple(),
293                      0/*TODO*/, Stream);
294  if (!M->getDataLayout().empty())
295    WriteStringRecord(bitc::MODULE_CODE_DATALAYOUT, M->getDataLayout(),
296                      0/*TODO*/, Stream);
297  if (!M->getModuleInlineAsm().empty())
298    WriteStringRecord(bitc::MODULE_CODE_ASM, M->getModuleInlineAsm(),
299                      0/*TODO*/, Stream);
300
301  // Emit information about sections, computing how many there are.  Also
302  // compute the maximum alignment value.
303  std::map<std::string, unsigned> SectionMap;
304  unsigned MaxAlignment = 0;
305  unsigned MaxGlobalType = 0;
306  for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end();
307       GV != E; ++GV) {
308    MaxAlignment = std::max(MaxAlignment, GV->getAlignment());
309    MaxGlobalType = std::max(MaxGlobalType, VE.getTypeID(GV->getType()));
310
311    if (!GV->hasSection()) continue;
312    // Give section names unique ID's.
313    unsigned &Entry = SectionMap[GV->getSection()];
314    if (Entry != 0) continue;
315    WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, GV->getSection(),
316                      0/*TODO*/, Stream);
317    Entry = SectionMap.size();
318  }
319  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
320    MaxAlignment = std::max(MaxAlignment, F->getAlignment());
321    if (!F->hasSection()) continue;
322    // Give section names unique ID's.
323    unsigned &Entry = SectionMap[F->getSection()];
324    if (Entry != 0) continue;
325    WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F->getSection(),
326                      0/*TODO*/, Stream);
327    Entry = SectionMap.size();
328  }
329
330  // Emit abbrev for globals, now that we know # sections and max alignment.
331  unsigned SimpleGVarAbbrev = 0;
332  if (!M->global_empty()) {
333    // Add an abbrev for common globals with no visibility or thread localness.
334    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
335    Abbv->Add(BitCodeAbbrevOp(bitc::MODULE_CODE_GLOBALVAR));
336    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
337                              Log2_32_Ceil(MaxGlobalType+1)));
338    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));      // Constant.
339    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));        // Initializer.
340    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3));      // Linkage.
341    if (MaxAlignment == 0)                                      // Alignment.
342      Abbv->Add(BitCodeAbbrevOp(0));
343    else {
344      unsigned MaxEncAlignment = Log2_32(MaxAlignment)+1;
345      Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
346                               Log2_32_Ceil(MaxEncAlignment+1)));
347    }
348    if (SectionMap.empty())                                    // Section.
349      Abbv->Add(BitCodeAbbrevOp(0));
350    else
351      Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
352                               Log2_32_Ceil(SectionMap.size()+1)));
353    // Don't bother emitting vis + thread local.
354    SimpleGVarAbbrev = Stream.EmitAbbrev(Abbv);
355  }
356
357  // Emit the global variable information.
358  SmallVector<unsigned, 64> Vals;
359  for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end();
360       GV != E; ++GV) {
361    unsigned AbbrevToUse = 0;
362
363    // GLOBALVAR: [type, isconst, initid,
364    //             linkage, alignment, section, visibility, threadlocal]
365    Vals.push_back(VE.getTypeID(GV->getType()));
366    Vals.push_back(GV->isConstant());
367    Vals.push_back(GV->isDeclaration() ? 0 :
368                   (VE.getValueID(GV->getInitializer()) + 1));
369    Vals.push_back(getEncodedLinkage(GV));
370    Vals.push_back(Log2_32(GV->getAlignment())+1);
371    Vals.push_back(GV->hasSection() ? SectionMap[GV->getSection()] : 0);
372    if (GV->isThreadLocal() ||
373        GV->getVisibility() != GlobalValue::DefaultVisibility) {
374      Vals.push_back(getEncodedVisibility(GV));
375      Vals.push_back(GV->isThreadLocal());
376    } else {
377      AbbrevToUse = SimpleGVarAbbrev;
378    }
379
380    Stream.EmitRecord(bitc::MODULE_CODE_GLOBALVAR, Vals, AbbrevToUse);
381    Vals.clear();
382  }
383
384  // Emit the function proto information.
385  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
386    // FUNCTION:  [type, callingconv, isproto, linkage, alignment, section,
387    //             visibility]
388    Vals.push_back(VE.getTypeID(F->getType()));
389    Vals.push_back(F->getCallingConv());
390    Vals.push_back(F->isDeclaration());
391    Vals.push_back(getEncodedLinkage(F));
392
393    // Note: we emit the param attr ID number for the function type of this
394    // function.  In the future, we intend for attrs to be properties of
395    // functions, instead of on the type.  This is to support this future work.
396    Vals.push_back(VE.getParamAttrID(F->getFunctionType()->getParamAttrs()));
397
398    Vals.push_back(Log2_32(F->getAlignment())+1);
399    Vals.push_back(F->hasSection() ? SectionMap[F->getSection()] : 0);
400    Vals.push_back(getEncodedVisibility(F));
401
402    unsigned AbbrevToUse = 0;
403    Stream.EmitRecord(bitc::MODULE_CODE_FUNCTION, Vals, AbbrevToUse);
404    Vals.clear();
405  }
406
407
408  // Emit the alias information.
409  for (Module::const_alias_iterator AI = M->alias_begin(), E = M->alias_end();
410       AI != E; ++AI) {
411    Vals.push_back(VE.getTypeID(AI->getType()));
412    Vals.push_back(VE.getValueID(AI->getAliasee()));
413    Vals.push_back(getEncodedLinkage(AI));
414    unsigned AbbrevToUse = 0;
415    Stream.EmitRecord(bitc::MODULE_CODE_ALIAS, Vals, AbbrevToUse);
416    Vals.clear();
417  }
418}
419
420
421static void WriteConstants(unsigned FirstVal, unsigned LastVal,
422                           const ValueEnumerator &VE,
423                           BitstreamWriter &Stream, bool isGlobal) {
424  if (FirstVal == LastVal) return;
425
426  Stream.EnterSubblock(bitc::CONSTANTS_BLOCK_ID, 4);
427
428  unsigned AggregateAbbrev = 0;
429  unsigned String8Abbrev = 0;
430  unsigned CString7Abbrev = 0;
431  unsigned CString6Abbrev = 0;
432  // If this is a constant pool for the module, emit module-specific abbrevs.
433  if (isGlobal) {
434    // Abbrev for CST_CODE_AGGREGATE.
435    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
436    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_AGGREGATE));
437    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
438    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, Log2_32_Ceil(LastVal+1)));
439    AggregateAbbrev = Stream.EmitAbbrev(Abbv);
440
441    // Abbrev for CST_CODE_STRING.
442    Abbv = new BitCodeAbbrev();
443    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_STRING));
444    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
445    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
446    String8Abbrev = Stream.EmitAbbrev(Abbv);
447    // Abbrev for CST_CODE_CSTRING.
448    Abbv = new BitCodeAbbrev();
449    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
450    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
451    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
452    CString7Abbrev = Stream.EmitAbbrev(Abbv);
453    // Abbrev for CST_CODE_CSTRING.
454    Abbv = new BitCodeAbbrev();
455    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
456    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
457    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
458    CString6Abbrev = Stream.EmitAbbrev(Abbv);
459  }
460
461  SmallVector<uint64_t, 64> Record;
462
463  const ValueEnumerator::ValueList &Vals = VE.getValues();
464  const Type *LastTy = 0;
465  for (unsigned i = FirstVal; i != LastVal; ++i) {
466    const Value *V = Vals[i].first;
467    // If we need to switch types, do so now.
468    if (V->getType() != LastTy) {
469      LastTy = V->getType();
470      Record.push_back(VE.getTypeID(LastTy));
471      Stream.EmitRecord(bitc::CST_CODE_SETTYPE, Record,
472                        CONSTANTS_SETTYPE_ABBREV);
473      Record.clear();
474    }
475
476    if (const InlineAsm *IA = dyn_cast<InlineAsm>(V)) {
477      Record.push_back(unsigned(IA->hasSideEffects()));
478
479      // Add the asm string.
480      const std::string &AsmStr = IA->getAsmString();
481      Record.push_back(AsmStr.size());
482      for (unsigned i = 0, e = AsmStr.size(); i != e; ++i)
483        Record.push_back(AsmStr[i]);
484
485      // Add the constraint string.
486      const std::string &ConstraintStr = IA->getConstraintString();
487      Record.push_back(ConstraintStr.size());
488      for (unsigned i = 0, e = ConstraintStr.size(); i != e; ++i)
489        Record.push_back(ConstraintStr[i]);
490      Stream.EmitRecord(bitc::CST_CODE_INLINEASM, Record);
491      Record.clear();
492      continue;
493    }
494    const Constant *C = cast<Constant>(V);
495    unsigned Code = -1U;
496    unsigned AbbrevToUse = 0;
497    if (C->isNullValue()) {
498      Code = bitc::CST_CODE_NULL;
499    } else if (isa<UndefValue>(C)) {
500      Code = bitc::CST_CODE_UNDEF;
501    } else if (const ConstantInt *IV = dyn_cast<ConstantInt>(C)) {
502      if (IV->getBitWidth() <= 64) {
503        int64_t V = IV->getSExtValue();
504        if (V >= 0)
505          Record.push_back(V << 1);
506        else
507          Record.push_back((-V << 1) | 1);
508        Code = bitc::CST_CODE_INTEGER;
509        AbbrevToUse = CONSTANTS_INTEGER_ABBREV;
510      } else {                             // Wide integers, > 64 bits in size.
511        // We have an arbitrary precision integer value to write whose
512        // bit width is > 64. However, in canonical unsigned integer
513        // format it is likely that the high bits are going to be zero.
514        // So, we only write the number of active words.
515        unsigned NWords = IV->getValue().getActiveWords();
516        const uint64_t *RawWords = IV->getValue().getRawData();
517        for (unsigned i = 0; i != NWords; ++i) {
518          int64_t V = RawWords[i];
519          if (V >= 0)
520            Record.push_back(V << 1);
521          else
522            Record.push_back((-V << 1) | 1);
523        }
524        Code = bitc::CST_CODE_WIDE_INTEGER;
525      }
526    } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
527      Code = bitc::CST_CODE_FLOAT;
528      const Type *Ty = CFP->getType();
529      if (Ty == Type::FloatTy)
530        Record.push_back(FloatToBits(CFP->getValueAPF().convertToFloat()));
531      else if (Ty == Type::DoubleTy) {
532        Record.push_back(DoubleToBits(CFP->getValueAPF().convertToDouble()));
533      // FIXME: make long double constants work.
534      } else if (Ty == Type::X86_FP80Ty ||
535                 Ty == Type::FP128Ty || Ty == Type::PPC_FP128Ty) {
536        assert (0 && "Long double constants not handled yet.");
537      } else {
538        assert (0 && "Unknown FP type!");
539      }
540    } else if (isa<ConstantArray>(C) && cast<ConstantArray>(C)->isString()) {
541      // Emit constant strings specially.
542      unsigned NumOps = C->getNumOperands();
543      // If this is a null-terminated string, use the denser CSTRING encoding.
544      if (C->getOperand(NumOps-1)->isNullValue()) {
545        Code = bitc::CST_CODE_CSTRING;
546        --NumOps;  // Don't encode the null, which isn't allowed by char6.
547      } else {
548        Code = bitc::CST_CODE_STRING;
549        AbbrevToUse = String8Abbrev;
550      }
551      bool isCStr7 = Code == bitc::CST_CODE_CSTRING;
552      bool isCStrChar6 = Code == bitc::CST_CODE_CSTRING;
553      for (unsigned i = 0; i != NumOps; ++i) {
554        unsigned char V = cast<ConstantInt>(C->getOperand(i))->getZExtValue();
555        Record.push_back(V);
556        isCStr7 &= (V & 128) == 0;
557        if (isCStrChar6)
558          isCStrChar6 = BitCodeAbbrevOp::isChar6(V);
559      }
560
561      if (isCStrChar6)
562        AbbrevToUse = CString6Abbrev;
563      else if (isCStr7)
564        AbbrevToUse = CString7Abbrev;
565    } else if (isa<ConstantArray>(C) || isa<ConstantStruct>(V) ||
566               isa<ConstantVector>(V)) {
567      Code = bitc::CST_CODE_AGGREGATE;
568      for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i)
569        Record.push_back(VE.getValueID(C->getOperand(i)));
570      AbbrevToUse = AggregateAbbrev;
571    } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
572      switch (CE->getOpcode()) {
573      default:
574        if (Instruction::isCast(CE->getOpcode())) {
575          Code = bitc::CST_CODE_CE_CAST;
576          Record.push_back(GetEncodedCastOpcode(CE->getOpcode()));
577          Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
578          Record.push_back(VE.getValueID(C->getOperand(0)));
579          AbbrevToUse = CONSTANTS_CE_CAST_Abbrev;
580        } else {
581          assert(CE->getNumOperands() == 2 && "Unknown constant expr!");
582          Code = bitc::CST_CODE_CE_BINOP;
583          Record.push_back(GetEncodedBinaryOpcode(CE->getOpcode()));
584          Record.push_back(VE.getValueID(C->getOperand(0)));
585          Record.push_back(VE.getValueID(C->getOperand(1)));
586        }
587        break;
588      case Instruction::GetElementPtr:
589        Code = bitc::CST_CODE_CE_GEP;
590        for (unsigned i = 0, e = CE->getNumOperands(); i != e; ++i) {
591          Record.push_back(VE.getTypeID(C->getOperand(i)->getType()));
592          Record.push_back(VE.getValueID(C->getOperand(i)));
593        }
594        break;
595      case Instruction::Select:
596        Code = bitc::CST_CODE_CE_SELECT;
597        Record.push_back(VE.getValueID(C->getOperand(0)));
598        Record.push_back(VE.getValueID(C->getOperand(1)));
599        Record.push_back(VE.getValueID(C->getOperand(2)));
600        break;
601      case Instruction::ExtractElement:
602        Code = bitc::CST_CODE_CE_EXTRACTELT;
603        Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
604        Record.push_back(VE.getValueID(C->getOperand(0)));
605        Record.push_back(VE.getValueID(C->getOperand(1)));
606        break;
607      case Instruction::InsertElement:
608        Code = bitc::CST_CODE_CE_INSERTELT;
609        Record.push_back(VE.getValueID(C->getOperand(0)));
610        Record.push_back(VE.getValueID(C->getOperand(1)));
611        Record.push_back(VE.getValueID(C->getOperand(2)));
612        break;
613      case Instruction::ShuffleVector:
614        Code = bitc::CST_CODE_CE_SHUFFLEVEC;
615        Record.push_back(VE.getValueID(C->getOperand(0)));
616        Record.push_back(VE.getValueID(C->getOperand(1)));
617        Record.push_back(VE.getValueID(C->getOperand(2)));
618        break;
619      case Instruction::ICmp:
620      case Instruction::FCmp:
621        Code = bitc::CST_CODE_CE_CMP;
622        Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
623        Record.push_back(VE.getValueID(C->getOperand(0)));
624        Record.push_back(VE.getValueID(C->getOperand(1)));
625        Record.push_back(CE->getPredicate());
626        break;
627      }
628    } else {
629      assert(0 && "Unknown constant!");
630    }
631    Stream.EmitRecord(Code, Record, AbbrevToUse);
632    Record.clear();
633  }
634
635  Stream.ExitBlock();
636}
637
638static void WriteModuleConstants(const ValueEnumerator &VE,
639                                 BitstreamWriter &Stream) {
640  const ValueEnumerator::ValueList &Vals = VE.getValues();
641
642  // Find the first constant to emit, which is the first non-globalvalue value.
643  // We know globalvalues have been emitted by WriteModuleInfo.
644  for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
645    if (!isa<GlobalValue>(Vals[i].first)) {
646      WriteConstants(i, Vals.size(), VE, Stream, true);
647      return;
648    }
649  }
650}
651
652/// PushValueAndType - The file has to encode both the value and type id for
653/// many values, because we need to know what type to create for forward
654/// references.  However, most operands are not forward references, so this type
655/// field is not needed.
656///
657/// This function adds V's value ID to Vals.  If the value ID is higher than the
658/// instruction ID, then it is a forward reference, and it also includes the
659/// type ID.
660static bool PushValueAndType(Value *V, unsigned InstID,
661                             SmallVector<unsigned, 64> &Vals,
662                             ValueEnumerator &VE) {
663  unsigned ValID = VE.getValueID(V);
664  Vals.push_back(ValID);
665  if (ValID >= InstID) {
666    Vals.push_back(VE.getTypeID(V->getType()));
667    return true;
668  }
669  return false;
670}
671
672/// WriteInstruction - Emit an instruction to the specified stream.
673static void WriteInstruction(const Instruction &I, unsigned InstID,
674                             ValueEnumerator &VE, BitstreamWriter &Stream,
675                             SmallVector<unsigned, 64> &Vals) {
676  unsigned Code = 0;
677  unsigned AbbrevToUse = 0;
678  switch (I.getOpcode()) {
679  default:
680    if (Instruction::isCast(I.getOpcode())) {
681      Code = bitc::FUNC_CODE_INST_CAST;
682      if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
683        AbbrevToUse = FUNCTION_INST_CAST_ABBREV;
684      Vals.push_back(VE.getTypeID(I.getType()));
685      Vals.push_back(GetEncodedCastOpcode(I.getOpcode()));
686    } else {
687      assert(isa<BinaryOperator>(I) && "Unknown instruction!");
688      Code = bitc::FUNC_CODE_INST_BINOP;
689      if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
690        AbbrevToUse = FUNCTION_INST_BINOP_ABBREV;
691      Vals.push_back(VE.getValueID(I.getOperand(1)));
692      Vals.push_back(GetEncodedBinaryOpcode(I.getOpcode()));
693    }
694    break;
695
696  case Instruction::GetElementPtr:
697    Code = bitc::FUNC_CODE_INST_GEP;
698    for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
699      PushValueAndType(I.getOperand(i), InstID, Vals, VE);
700    break;
701  case Instruction::Select:
702    Code = bitc::FUNC_CODE_INST_SELECT;
703    PushValueAndType(I.getOperand(1), InstID, Vals, VE);
704    Vals.push_back(VE.getValueID(I.getOperand(2)));
705    Vals.push_back(VE.getValueID(I.getOperand(0)));
706    break;
707  case Instruction::ExtractElement:
708    Code = bitc::FUNC_CODE_INST_EXTRACTELT;
709    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
710    Vals.push_back(VE.getValueID(I.getOperand(1)));
711    break;
712  case Instruction::InsertElement:
713    Code = bitc::FUNC_CODE_INST_INSERTELT;
714    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
715    Vals.push_back(VE.getValueID(I.getOperand(1)));
716    Vals.push_back(VE.getValueID(I.getOperand(2)));
717    break;
718  case Instruction::ShuffleVector:
719    Code = bitc::FUNC_CODE_INST_SHUFFLEVEC;
720    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
721    Vals.push_back(VE.getValueID(I.getOperand(1)));
722    Vals.push_back(VE.getValueID(I.getOperand(2)));
723    break;
724  case Instruction::ICmp:
725  case Instruction::FCmp:
726    Code = bitc::FUNC_CODE_INST_CMP;
727    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
728    Vals.push_back(VE.getValueID(I.getOperand(1)));
729    Vals.push_back(cast<CmpInst>(I).getPredicate());
730    break;
731
732  case Instruction::Ret:
733    Code = bitc::FUNC_CODE_INST_RET;
734    if (!I.getNumOperands())
735      AbbrevToUse = FUNCTION_INST_RET_VOID_ABBREV;
736    else if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
737      AbbrevToUse = FUNCTION_INST_RET_VAL_ABBREV;
738    break;
739  case Instruction::Br:
740    Code = bitc::FUNC_CODE_INST_BR;
741    Vals.push_back(VE.getValueID(I.getOperand(0)));
742    if (cast<BranchInst>(I).isConditional()) {
743      Vals.push_back(VE.getValueID(I.getOperand(1)));
744      Vals.push_back(VE.getValueID(I.getOperand(2)));
745    }
746    break;
747  case Instruction::Switch:
748    Code = bitc::FUNC_CODE_INST_SWITCH;
749    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
750    for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
751      Vals.push_back(VE.getValueID(I.getOperand(i)));
752    break;
753  case Instruction::Invoke: {
754    const PointerType *PTy = cast<PointerType>(I.getOperand(0)->getType());
755    const FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
756    Code = bitc::FUNC_CODE_INST_INVOKE;
757
758    // Note: we emit the param attr ID number for the function type of this
759    // function.  In the future, we intend for attrs to be properties of
760    // functions, instead of on the type.  This is to support this future work.
761    Vals.push_back(VE.getParamAttrID(FTy->getParamAttrs()));
762
763    Vals.push_back(cast<InvokeInst>(I).getCallingConv());
764    Vals.push_back(VE.getValueID(I.getOperand(1)));      // normal dest
765    Vals.push_back(VE.getValueID(I.getOperand(2)));      // unwind dest
766    PushValueAndType(I.getOperand(0), InstID, Vals, VE); // callee
767
768    // Emit value #'s for the fixed parameters.
769    for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
770      Vals.push_back(VE.getValueID(I.getOperand(i+3)));  // fixed param.
771
772    // Emit type/value pairs for varargs params.
773    if (FTy->isVarArg()) {
774      for (unsigned i = 3+FTy->getNumParams(), e = I.getNumOperands();
775           i != e; ++i)
776        PushValueAndType(I.getOperand(i), InstID, Vals, VE); // vararg
777    }
778    break;
779  }
780  case Instruction::Unwind:
781    Code = bitc::FUNC_CODE_INST_UNWIND;
782    break;
783  case Instruction::Unreachable:
784    Code = bitc::FUNC_CODE_INST_UNREACHABLE;
785    AbbrevToUse = FUNCTION_INST_UNREACHABLE_ABBREV;
786    break;
787
788  case Instruction::PHI:
789    Code = bitc::FUNC_CODE_INST_PHI;
790    Vals.push_back(VE.getTypeID(I.getType()));
791    for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
792      Vals.push_back(VE.getValueID(I.getOperand(i)));
793    break;
794
795  case Instruction::Malloc:
796    Code = bitc::FUNC_CODE_INST_MALLOC;
797    Vals.push_back(VE.getTypeID(I.getType()));
798    Vals.push_back(VE.getValueID(I.getOperand(0))); // size.
799    Vals.push_back(Log2_32(cast<MallocInst>(I).getAlignment())+1);
800    break;
801
802  case Instruction::Free:
803    Code = bitc::FUNC_CODE_INST_FREE;
804    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
805    break;
806
807  case Instruction::Alloca:
808    Code = bitc::FUNC_CODE_INST_ALLOCA;
809    Vals.push_back(VE.getTypeID(I.getType()));
810    Vals.push_back(VE.getValueID(I.getOperand(0))); // size.
811    Vals.push_back(Log2_32(cast<AllocaInst>(I).getAlignment())+1);
812    break;
813
814  case Instruction::Load:
815    Code = bitc::FUNC_CODE_INST_LOAD;
816    if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))  // ptr
817      AbbrevToUse = FUNCTION_INST_LOAD_ABBREV;
818
819    Vals.push_back(Log2_32(cast<LoadInst>(I).getAlignment())+1);
820    Vals.push_back(cast<LoadInst>(I).isVolatile());
821    break;
822  case Instruction::Store:
823    Code = bitc::FUNC_CODE_INST_STORE;
824    PushValueAndType(I.getOperand(0), InstID, Vals, VE);  // val.
825    Vals.push_back(VE.getValueID(I.getOperand(1)));       // ptr.
826    Vals.push_back(Log2_32(cast<StoreInst>(I).getAlignment())+1);
827    Vals.push_back(cast<StoreInst>(I).isVolatile());
828    break;
829  case Instruction::Call: {
830    const PointerType *PTy = cast<PointerType>(I.getOperand(0)->getType());
831    const FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
832
833    Code = bitc::FUNC_CODE_INST_CALL;
834
835    // Note: we emit the param attr ID number for the function type of this
836    // function.  In the future, we intend for attrs to be properties of
837    // functions, instead of on the type.  This is to support this future work.
838    Vals.push_back(VE.getParamAttrID(FTy->getParamAttrs()));
839
840    Vals.push_back((cast<CallInst>(I).getCallingConv() << 1) |
841                   unsigned(cast<CallInst>(I).isTailCall()));
842    PushValueAndType(I.getOperand(0), InstID, Vals, VE);  // Callee
843
844    // Emit value #'s for the fixed parameters.
845    for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
846      Vals.push_back(VE.getValueID(I.getOperand(i+1)));  // fixed param.
847
848    // Emit type/value pairs for varargs params.
849    if (FTy->isVarArg()) {
850      unsigned NumVarargs = I.getNumOperands()-1-FTy->getNumParams();
851      for (unsigned i = I.getNumOperands()-NumVarargs, e = I.getNumOperands();
852           i != e; ++i)
853        PushValueAndType(I.getOperand(i), InstID, Vals, VE);  // varargs
854    }
855    break;
856  }
857  case Instruction::VAArg:
858    Code = bitc::FUNC_CODE_INST_VAARG;
859    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));   // valistty
860    Vals.push_back(VE.getValueID(I.getOperand(0))); // valist.
861    Vals.push_back(VE.getTypeID(I.getType())); // restype.
862    break;
863  }
864
865  Stream.EmitRecord(Code, Vals, AbbrevToUse);
866  Vals.clear();
867}
868
869// Emit names for globals/functions etc.
870static void WriteValueSymbolTable(const ValueSymbolTable &VST,
871                                  const ValueEnumerator &VE,
872                                  BitstreamWriter &Stream) {
873  if (VST.empty()) return;
874  Stream.EnterSubblock(bitc::VALUE_SYMTAB_BLOCK_ID, 4);
875
876  // FIXME: Set up the abbrev, we know how many values there are!
877  // FIXME: We know if the type names can use 7-bit ascii.
878  SmallVector<unsigned, 64> NameVals;
879
880  for (ValueSymbolTable::const_iterator SI = VST.begin(), SE = VST.end();
881       SI != SE; ++SI) {
882
883    const ValueName &Name = *SI;
884
885    // Figure out the encoding to use for the name.
886    bool is7Bit = true;
887    bool isChar6 = true;
888    for (const char *C = Name.getKeyData(), *E = C+Name.getKeyLength();
889         C != E; ++C) {
890      if (isChar6)
891        isChar6 = BitCodeAbbrevOp::isChar6(*C);
892      if ((unsigned char)*C & 128) {
893        is7Bit = false;
894        break;  // don't bother scanning the rest.
895      }
896    }
897
898    unsigned AbbrevToUse = VST_ENTRY_8_ABBREV;
899
900    // VST_ENTRY:   [valueid, namechar x N]
901    // VST_BBENTRY: [bbid, namechar x N]
902    unsigned Code;
903    if (isa<BasicBlock>(SI->getValue())) {
904      Code = bitc::VST_CODE_BBENTRY;
905      if (isChar6)
906        AbbrevToUse = VST_BBENTRY_6_ABBREV;
907    } else {
908      Code = bitc::VST_CODE_ENTRY;
909      if (isChar6)
910        AbbrevToUse = VST_ENTRY_6_ABBREV;
911      else if (is7Bit)
912        AbbrevToUse = VST_ENTRY_7_ABBREV;
913    }
914
915    NameVals.push_back(VE.getValueID(SI->getValue()));
916    for (const char *P = Name.getKeyData(),
917         *E = Name.getKeyData()+Name.getKeyLength(); P != E; ++P)
918      NameVals.push_back((unsigned char)*P);
919
920    // Emit the finished record.
921    Stream.EmitRecord(Code, NameVals, AbbrevToUse);
922    NameVals.clear();
923  }
924  Stream.ExitBlock();
925}
926
927/// WriteFunction - Emit a function body to the module stream.
928static void WriteFunction(const Function &F, ValueEnumerator &VE,
929                          BitstreamWriter &Stream) {
930  Stream.EnterSubblock(bitc::FUNCTION_BLOCK_ID, 4);
931  VE.incorporateFunction(F);
932
933  SmallVector<unsigned, 64> Vals;
934
935  // Emit the number of basic blocks, so the reader can create them ahead of
936  // time.
937  Vals.push_back(VE.getBasicBlocks().size());
938  Stream.EmitRecord(bitc::FUNC_CODE_DECLAREBLOCKS, Vals);
939  Vals.clear();
940
941  // If there are function-local constants, emit them now.
942  unsigned CstStart, CstEnd;
943  VE.getFunctionConstantRange(CstStart, CstEnd);
944  WriteConstants(CstStart, CstEnd, VE, Stream, false);
945
946  // Keep a running idea of what the instruction ID is.
947  unsigned InstID = CstEnd;
948
949  // Finally, emit all the instructions, in order.
950  for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
951    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
952         I != E; ++I) {
953      WriteInstruction(*I, InstID, VE, Stream, Vals);
954      if (I->getType() != Type::VoidTy)
955        ++InstID;
956    }
957
958  // Emit names for all the instructions etc.
959  WriteValueSymbolTable(F.getValueSymbolTable(), VE, Stream);
960
961  VE.purgeFunction();
962  Stream.ExitBlock();
963}
964
965/// WriteTypeSymbolTable - Emit a block for the specified type symtab.
966static void WriteTypeSymbolTable(const TypeSymbolTable &TST,
967                                 const ValueEnumerator &VE,
968                                 BitstreamWriter &Stream) {
969  if (TST.empty()) return;
970
971  Stream.EnterSubblock(bitc::TYPE_SYMTAB_BLOCK_ID, 3);
972
973  // 7-bit fixed width VST_CODE_ENTRY strings.
974  BitCodeAbbrev *Abbv = new BitCodeAbbrev();
975  Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
976  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
977                            Log2_32_Ceil(VE.getTypes().size()+1)));
978  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
979  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
980  unsigned V7Abbrev = Stream.EmitAbbrev(Abbv);
981
982  SmallVector<unsigned, 64> NameVals;
983
984  for (TypeSymbolTable::const_iterator TI = TST.begin(), TE = TST.end();
985       TI != TE; ++TI) {
986    // TST_ENTRY: [typeid, namechar x N]
987    NameVals.push_back(VE.getTypeID(TI->second));
988
989    const std::string &Str = TI->first;
990    bool is7Bit = true;
991    for (unsigned i = 0, e = Str.size(); i != e; ++i) {
992      NameVals.push_back((unsigned char)Str[i]);
993      if (Str[i] & 128)
994        is7Bit = false;
995    }
996
997    // Emit the finished record.
998    Stream.EmitRecord(bitc::VST_CODE_ENTRY, NameVals, is7Bit ? V7Abbrev : 0);
999    NameVals.clear();
1000  }
1001
1002  Stream.ExitBlock();
1003}
1004
1005// Emit blockinfo, which defines the standard abbreviations etc.
1006static void WriteBlockInfo(const ValueEnumerator &VE, BitstreamWriter &Stream) {
1007  // We only want to emit block info records for blocks that have multiple
1008  // instances: CONSTANTS_BLOCK, FUNCTION_BLOCK and VALUE_SYMTAB_BLOCK.  Other
1009  // blocks can defined their abbrevs inline.
1010  Stream.EnterBlockInfoBlock(2);
1011
1012  { // 8-bit fixed-width VST_ENTRY/VST_BBENTRY strings.
1013    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1014    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3));
1015    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1016    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1017    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
1018    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1019                                   Abbv) != VST_ENTRY_8_ABBREV)
1020      assert(0 && "Unexpected abbrev ordering!");
1021  }
1022
1023  { // 7-bit fixed width VST_ENTRY strings.
1024    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1025    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1026    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1027    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1028    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
1029    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1030                                   Abbv) != VST_ENTRY_7_ABBREV)
1031      assert(0 && "Unexpected abbrev ordering!");
1032  }
1033  { // 6-bit char6 VST_ENTRY strings.
1034    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1035    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1036    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1037    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1038    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1039    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1040                                   Abbv) != VST_ENTRY_6_ABBREV)
1041      assert(0 && "Unexpected abbrev ordering!");
1042  }
1043  { // 6-bit char6 VST_BBENTRY strings.
1044    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1045    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_BBENTRY));
1046    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1047    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1048    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1049    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1050                                   Abbv) != VST_BBENTRY_6_ABBREV)
1051      assert(0 && "Unexpected abbrev ordering!");
1052  }
1053
1054
1055
1056  { // SETTYPE abbrev for CONSTANTS_BLOCK.
1057    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1058    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_SETTYPE));
1059    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1060                              Log2_32_Ceil(VE.getTypes().size()+1)));
1061    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1062                                   Abbv) != CONSTANTS_SETTYPE_ABBREV)
1063      assert(0 && "Unexpected abbrev ordering!");
1064  }
1065
1066  { // INTEGER abbrev for CONSTANTS_BLOCK.
1067    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1068    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_INTEGER));
1069    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1070    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1071                                   Abbv) != CONSTANTS_INTEGER_ABBREV)
1072      assert(0 && "Unexpected abbrev ordering!");
1073  }
1074
1075  { // CE_CAST abbrev for CONSTANTS_BLOCK.
1076    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1077    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CE_CAST));
1078    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // cast opc
1079    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // typeid
1080                              Log2_32_Ceil(VE.getTypes().size()+1)));
1081    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));    // value id
1082
1083    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1084                                   Abbv) != CONSTANTS_CE_CAST_Abbrev)
1085      assert(0 && "Unexpected abbrev ordering!");
1086  }
1087  { // NULL abbrev for CONSTANTS_BLOCK.
1088    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1089    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_NULL));
1090    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1091                                   Abbv) != CONSTANTS_NULL_Abbrev)
1092      assert(0 && "Unexpected abbrev ordering!");
1093  }
1094
1095  // FIXME: This should only use space for first class types!
1096
1097  { // INST_LOAD abbrev for FUNCTION_BLOCK.
1098    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1099    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_LOAD));
1100    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Ptr
1101    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4)); // Align
1102    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // volatile
1103    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1104                                   Abbv) != FUNCTION_INST_LOAD_ABBREV)
1105      assert(0 && "Unexpected abbrev ordering!");
1106  }
1107  { // INST_BINOP abbrev for FUNCTION_BLOCK.
1108    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1109    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1110    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1111    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1112    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1113    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1114                                   Abbv) != FUNCTION_INST_BINOP_ABBREV)
1115      assert(0 && "Unexpected abbrev ordering!");
1116  }
1117  { // INST_CAST abbrev for FUNCTION_BLOCK.
1118    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1119    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_CAST));
1120    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));    // OpVal
1121    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // dest ty
1122                              Log2_32_Ceil(VE.getTypes().size()+1)));
1123    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // opc
1124    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1125                                   Abbv) != FUNCTION_INST_CAST_ABBREV)
1126      assert(0 && "Unexpected abbrev ordering!");
1127  }
1128
1129  { // INST_RET abbrev for FUNCTION_BLOCK.
1130    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1131    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1132    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1133                                   Abbv) != FUNCTION_INST_RET_VOID_ABBREV)
1134      assert(0 && "Unexpected abbrev ordering!");
1135  }
1136  { // INST_RET abbrev for FUNCTION_BLOCK.
1137    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1138    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1139    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ValID
1140    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1141                                   Abbv) != FUNCTION_INST_RET_VAL_ABBREV)
1142      assert(0 && "Unexpected abbrev ordering!");
1143  }
1144  { // INST_UNREACHABLE abbrev for FUNCTION_BLOCK.
1145    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1146    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_UNREACHABLE));
1147    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1148                                   Abbv) != FUNCTION_INST_UNREACHABLE_ABBREV)
1149      assert(0 && "Unexpected abbrev ordering!");
1150  }
1151
1152  Stream.ExitBlock();
1153}
1154
1155
1156/// WriteModule - Emit the specified module to the bitstream.
1157static void WriteModule(const Module *M, BitstreamWriter &Stream) {
1158  Stream.EnterSubblock(bitc::MODULE_BLOCK_ID, 3);
1159
1160  // Emit the version number if it is non-zero.
1161  if (CurVersion) {
1162    SmallVector<unsigned, 1> Vals;
1163    Vals.push_back(CurVersion);
1164    Stream.EmitRecord(bitc::MODULE_CODE_VERSION, Vals);
1165  }
1166
1167  // Analyze the module, enumerating globals, functions, etc.
1168  ValueEnumerator VE(M);
1169
1170  // Emit blockinfo, which defines the standard abbreviations etc.
1171  WriteBlockInfo(VE, Stream);
1172
1173  // Emit information about parameter attributes.
1174  WriteParamAttrTable(VE, Stream);
1175
1176  // Emit information describing all of the types in the module.
1177  WriteTypeTable(VE, Stream);
1178
1179  // Emit top-level description of module, including target triple, inline asm,
1180  // descriptors for global variables, and function prototype info.
1181  WriteModuleInfo(M, VE, Stream);
1182
1183  // Emit constants.
1184  WriteModuleConstants(VE, Stream);
1185
1186  // If we have any aggregate values in the value table, purge them - these can
1187  // only be used to initialize global variables.  Doing so makes the value
1188  // namespace smaller for code in functions.
1189  int NumNonAggregates = VE.PurgeAggregateValues();
1190  if (NumNonAggregates != -1) {
1191    SmallVector<unsigned, 1> Vals;
1192    Vals.push_back(NumNonAggregates);
1193    Stream.EmitRecord(bitc::MODULE_CODE_PURGEVALS, Vals);
1194  }
1195
1196  // Emit function bodies.
1197  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I)
1198    if (!I->isDeclaration())
1199      WriteFunction(*I, VE, Stream);
1200
1201  // Emit the type symbol table information.
1202  WriteTypeSymbolTable(M->getTypeSymbolTable(), VE, Stream);
1203
1204  // Emit names for globals/functions etc.
1205  WriteValueSymbolTable(M->getValueSymbolTable(), VE, Stream);
1206
1207  Stream.ExitBlock();
1208}
1209
1210
1211/// WriteBitcodeToFile - Write the specified module to the specified output
1212/// stream.
1213void llvm::WriteBitcodeToFile(const Module *M, std::ostream &Out) {
1214  std::vector<unsigned char> Buffer;
1215  BitstreamWriter Stream(Buffer);
1216
1217  Buffer.reserve(256*1024);
1218
1219  // Emit the file header.
1220  Stream.Emit((unsigned)'B', 8);
1221  Stream.Emit((unsigned)'C', 8);
1222  Stream.Emit(0x0, 4);
1223  Stream.Emit(0xC, 4);
1224  Stream.Emit(0xE, 4);
1225  Stream.Emit(0xD, 4);
1226
1227  // Emit the module.
1228  WriteModule(M, Stream);
1229
1230  // Write the generated bitstream to "Out".
1231  Out.write((char*)&Buffer.front(), Buffer.size());
1232
1233  // Make sure it hits disk now.
1234  Out.flush();
1235}
1236