BitcodeWriter.cpp revision 0da7f6c8201b27938d3b9f048d71fd784cd1df9a 
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.h"
15#include "ValueEnumerator.h"
16#include "llvm/ADT/Triple.h"
17#include "llvm/Bitcode/BitstreamWriter.h"
18#include "llvm/Bitcode/LLVMBitCodes.h"
19#include "llvm/IR/Constants.h"
20#include "llvm/IR/DerivedTypes.h"
21#include "llvm/IR/InlineAsm.h"
22#include "llvm/IR/Instructions.h"
23#include "llvm/IR/Module.h"
24#include "llvm/IR/Operator.h"
25#include "llvm/IR/ValueSymbolTable.h"
26#include "llvm/Support/ErrorHandling.h"
27#include "llvm/Support/MathExtras.h"
28#include "llvm/Support/Program.h"
29#include "llvm/Support/raw_ostream.h"
30#include <cctype>
31#include <map>
32using namespace llvm;
33
34// Redefine older bitcode opcodes for use here. Note that these come from
35// LLVM 2.7 (which is what HC shipped with).
36#define METADATA_NODE_2_7             2
37#define METADATA_FN_NODE_2_7          3
38#define METADATA_NAMED_NODE_2_7       5
39#define METADATA_ATTACHMENT_2_7       7
40#define FUNC_CODE_INST_CALL_2_7       22
41#define FUNC_CODE_DEBUG_LOC_2_7       32
42
43// Redefine older bitcode opcodes for use here. Note that these come from
44// LLVM 2.7 - 3.0.
45#define TYPE_BLOCK_ID_OLD_3_0 10
46#define TYPE_SYMTAB_BLOCK_ID_OLD_3_0 13
47#define TYPE_CODE_STRUCT_OLD_3_0 10
48
49/// These are manifest constants used by the bitcode writer. They do not need to
50/// be kept in sync with the reader, but need to be consistent within this file.
51enum {
52  CurVersion = 0,
53
54  // VALUE_SYMTAB_BLOCK abbrev id's.
55  VST_ENTRY_8_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
56  VST_ENTRY_7_ABBREV,
57  VST_ENTRY_6_ABBREV,
58  VST_BBENTRY_6_ABBREV,
59
60  // CONSTANTS_BLOCK abbrev id's.
61  CONSTANTS_SETTYPE_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
62  CONSTANTS_INTEGER_ABBREV,
63  CONSTANTS_CE_CAST_Abbrev,
64  CONSTANTS_NULL_Abbrev,
65
66  // FUNCTION_BLOCK abbrev id's.
67  FUNCTION_INST_LOAD_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
68  FUNCTION_INST_BINOP_ABBREV,
69  FUNCTION_INST_BINOP_FLAGS_ABBREV,
70  FUNCTION_INST_CAST_ABBREV,
71  FUNCTION_INST_RET_VOID_ABBREV,
72  FUNCTION_INST_RET_VAL_ABBREV,
73  FUNCTION_INST_UNREACHABLE_ABBREV
74};
75
76
77static unsigned GetEncodedCastOpcode(unsigned Opcode) {
78  switch (Opcode) {
79  default: llvm_unreachable("Unknown cast instruction!");
80  case Instruction::Trunc   : return bitc::CAST_TRUNC;
81  case Instruction::ZExt    : return bitc::CAST_ZEXT;
82  case Instruction::SExt    : return bitc::CAST_SEXT;
83  case Instruction::FPToUI  : return bitc::CAST_FPTOUI;
84  case Instruction::FPToSI  : return bitc::CAST_FPTOSI;
85  case Instruction::UIToFP  : return bitc::CAST_UITOFP;
86  case Instruction::SIToFP  : return bitc::CAST_SITOFP;
87  case Instruction::FPTrunc : return bitc::CAST_FPTRUNC;
88  case Instruction::FPExt   : return bitc::CAST_FPEXT;
89  case Instruction::PtrToInt: return bitc::CAST_PTRTOINT;
90  case Instruction::IntToPtr: return bitc::CAST_INTTOPTR;
91  case Instruction::BitCast : return bitc::CAST_BITCAST;
92  }
93}
94
95static unsigned GetEncodedBinaryOpcode(unsigned Opcode) {
96  switch (Opcode) {
97  default: llvm_unreachable("Unknown binary instruction!");
98  case Instruction::Add:
99  case Instruction::FAdd: return bitc::BINOP_ADD;
100  case Instruction::Sub:
101  case Instruction::FSub: return bitc::BINOP_SUB;
102  case Instruction::Mul:
103  case Instruction::FMul: return bitc::BINOP_MUL;
104  case Instruction::UDiv: return bitc::BINOP_UDIV;
105  case Instruction::FDiv:
106  case Instruction::SDiv: return bitc::BINOP_SDIV;
107  case Instruction::URem: return bitc::BINOP_UREM;
108  case Instruction::FRem:
109  case Instruction::SRem: return bitc::BINOP_SREM;
110  case Instruction::Shl:  return bitc::BINOP_SHL;
111  case Instruction::LShr: return bitc::BINOP_LSHR;
112  case Instruction::AShr: return bitc::BINOP_ASHR;
113  case Instruction::And:  return bitc::BINOP_AND;
114  case Instruction::Or:   return bitc::BINOP_OR;
115  case Instruction::Xor:  return bitc::BINOP_XOR;
116  }
117}
118
119static void WriteStringRecord(unsigned Code, StringRef Str,
120                              unsigned AbbrevToUse, BitstreamWriter &Stream) {
121  SmallVector<unsigned, 64> Vals;
122
123  // Code: [strchar x N]
124  for (unsigned i = 0, e = Str.size(); i != e; ++i) {
125    if (AbbrevToUse && !BitCodeAbbrevOp::isChar6(Str[i]))
126      AbbrevToUse = 0;
127    Vals.push_back(Str[i]);
128  }
129
130  // Emit the finished record.
131  Stream.EmitRecord(Code, Vals, AbbrevToUse);
132}
133
134// Emit information about parameter attributes.
135static void WriteAttributeTable(const llvm_2_9::ValueEnumerator &VE,
136                                BitstreamWriter &Stream) {
137  const std::vector<AttributeSet> &Attrs = VE.getAttributes();
138  if (Attrs.empty()) return;
139
140  Stream.EnterSubblock(bitc::PARAMATTR_BLOCK_ID, 3);
141
142  SmallVector<uint64_t, 64> Record;
143  for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
144    const AttributeSet &A = Attrs[i];
145    for (unsigned i = 0, e = A.getNumSlots(); i != e; ++i)
146      Record.push_back(VE.getAttributeGroupID(A.getSlotAttributes(i)));
147
148    Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY, Record);
149    Record.clear();
150  }
151
152  Stream.ExitBlock();
153}
154
155static void WriteTypeSymbolTable(const llvm_2_9::ValueEnumerator &VE,
156                                 BitstreamWriter &Stream) {
157  const llvm_2_9::ValueEnumerator::TypeList &TypeList = VE.getTypes();
158  Stream.EnterSubblock(TYPE_SYMTAB_BLOCK_ID_OLD_3_0, 3);
159
160  // 7-bit fixed width VST_CODE_ENTRY strings.
161  BitCodeAbbrev *Abbv = new BitCodeAbbrev();
162  Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
163  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
164                            Log2_32_Ceil(VE.getTypes().size()+1)));
165  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
166  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
167  unsigned V7Abbrev = Stream.EmitAbbrev(Abbv);
168
169  SmallVector<unsigned, 64> NameVals;
170
171  for (unsigned i = 0, e = TypeList.size(); i != e; ++i) {
172    Type *T = TypeList[i];
173
174    switch (T->getTypeID()) {
175    case Type::StructTyID: {
176      StructType *ST = cast<StructType>(T);
177      if (ST->isLiteral()) {
178        // Skip anonymous struct definitions in type symbol table
179        // FIXME(srhines)
180        break;
181      }
182
183      // TST_ENTRY: [typeid, namechar x N]
184      NameVals.push_back(i);
185
186      const std::string &Str = ST->getName();
187      bool is7Bit = true;
188      for (unsigned i = 0, e = Str.size(); i != e; ++i) {
189        NameVals.push_back((unsigned char)Str[i]);
190        if (Str[i] & 128)
191          is7Bit = false;
192      }
193
194      // Emit the finished record.
195      Stream.EmitRecord(bitc::VST_CODE_ENTRY, NameVals, is7Bit ? V7Abbrev : 0);
196      NameVals.clear();
197
198      break;
199    }
200    default: break;
201    }
202  }
203
204#if 0
205  for (TypeSymbolTable::const_iterator TI = TST.begin(), TE = TST.end();
206       TI != TE; ++TI) {
207    // TST_ENTRY: [typeid, namechar x N]
208    NameVals.push_back(VE.getTypeID(TI->second));
209
210    const std::string &Str = TI->first;
211    bool is7Bit = true;
212    for (unsigned i = 0, e = Str.size(); i != e; ++i) {
213      NameVals.push_back((unsigned char)Str[i]);
214      if (Str[i] & 128)
215        is7Bit = false;
216    }
217
218    // Emit the finished record.
219    Stream.EmitRecord(bitc::VST_CODE_ENTRY, NameVals, is7Bit ? V7Abbrev : 0);
220    NameVals.clear();
221  }
222#endif
223
224  Stream.ExitBlock();
225}
226
227/// WriteTypeTable - Write out the type table for a module.
228static void WriteTypeTable(const llvm_2_9::ValueEnumerator &VE,
229                           BitstreamWriter &Stream) {
230  const llvm_2_9::ValueEnumerator::TypeList &TypeList = VE.getTypes();
231
232  Stream.EnterSubblock(TYPE_BLOCK_ID_OLD_3_0, 4 /*count from # abbrevs */);
233  SmallVector<uint64_t, 64> TypeVals;
234
235  // Abbrev for TYPE_CODE_POINTER.
236  BitCodeAbbrev *Abbv = new BitCodeAbbrev();
237  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_POINTER));
238  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
239                            Log2_32_Ceil(VE.getTypes().size()+1)));
240  Abbv->Add(BitCodeAbbrevOp(0));  // Addrspace = 0
241  unsigned PtrAbbrev = Stream.EmitAbbrev(Abbv);
242
243  // Abbrev for TYPE_CODE_FUNCTION.
244  Abbv = new BitCodeAbbrev();
245  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_FUNCTION_OLD));
246  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // isvararg
247  Abbv->Add(BitCodeAbbrevOp(0));  // FIXME: DEAD value, remove in LLVM 3.0
248  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
249  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
250                            Log2_32_Ceil(VE.getTypes().size()+1)));
251  unsigned FunctionAbbrev = Stream.EmitAbbrev(Abbv);
252
253#if 0
254  // Abbrev for TYPE_CODE_STRUCT_ANON.
255  Abbv = new BitCodeAbbrev();
256  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_ANON));
257  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // ispacked
258  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
259  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
260                            Log2_32_Ceil(VE.getTypes().size()+1)));
261  unsigned StructAnonAbbrev = Stream.EmitAbbrev(Abbv);
262
263  // Abbrev for TYPE_CODE_STRUCT_NAME.
264  Abbv = new BitCodeAbbrev();
265  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_NAME));
266  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
267  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
268  unsigned StructNameAbbrev = Stream.EmitAbbrev(Abbv);
269
270  // Abbrev for TYPE_CODE_STRUCT_NAMED.
271  Abbv = new BitCodeAbbrev();
272  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_NAMED));
273  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // ispacked
274  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
275  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
276                            Log2_32_Ceil(VE.getTypes().size()+1)));
277  unsigned StructNamedAbbrev = Stream.EmitAbbrev(Abbv);
278#endif
279
280  // Abbrev for TYPE_CODE_STRUCT.
281  Abbv = new BitCodeAbbrev();
282  Abbv->Add(BitCodeAbbrevOp(TYPE_CODE_STRUCT_OLD_3_0));
283  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // ispacked
284  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
285  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
286                            Log2_32_Ceil(VE.getTypes().size()+1)));
287  unsigned StructAbbrev = Stream.EmitAbbrev(Abbv);
288
289  // Abbrev for TYPE_CODE_ARRAY.
290  Abbv = new BitCodeAbbrev();
291  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_ARRAY));
292  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // size
293  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
294                            Log2_32_Ceil(VE.getTypes().size()+1)));
295  unsigned ArrayAbbrev = Stream.EmitAbbrev(Abbv);
296
297  // Emit an entry count so the reader can reserve space.
298  TypeVals.push_back(TypeList.size());
299  Stream.EmitRecord(bitc::TYPE_CODE_NUMENTRY, TypeVals);
300  TypeVals.clear();
301
302  // Loop over all of the types, emitting each in turn.
303  for (unsigned i = 0, e = TypeList.size(); i != e; ++i) {
304    Type *T = TypeList[i];
305    int AbbrevToUse = 0;
306    unsigned Code = 0;
307
308    switch (T->getTypeID()) {
309    default: llvm_unreachable("Unknown type!");
310    case Type::VoidTyID:      Code = bitc::TYPE_CODE_VOID;   break;
311    case Type::FloatTyID:     Code = bitc::TYPE_CODE_FLOAT;  break;
312    case Type::DoubleTyID:    Code = bitc::TYPE_CODE_DOUBLE; break;
313    case Type::X86_FP80TyID:  Code = bitc::TYPE_CODE_X86_FP80; break;
314    case Type::FP128TyID:     Code = bitc::TYPE_CODE_FP128; break;
315    case Type::PPC_FP128TyID: Code = bitc::TYPE_CODE_PPC_FP128; break;
316    case Type::LabelTyID:     Code = bitc::TYPE_CODE_LABEL;  break;
317    case Type::MetadataTyID:  Code = bitc::TYPE_CODE_METADATA; break;
318    case Type::X86_MMXTyID:   Code = bitc::TYPE_CODE_X86_MMX; break;
319    case Type::IntegerTyID:
320      // INTEGER: [width]
321      Code = bitc::TYPE_CODE_INTEGER;
322      TypeVals.push_back(cast<IntegerType>(T)->getBitWidth());
323      break;
324    case Type::PointerTyID: {
325      PointerType *PTy = cast<PointerType>(T);
326      // POINTER: [pointee type, address space]
327      Code = bitc::TYPE_CODE_POINTER;
328      TypeVals.push_back(VE.getTypeID(PTy->getElementType()));
329      unsigned AddressSpace = PTy->getAddressSpace();
330      TypeVals.push_back(AddressSpace);
331      if (AddressSpace == 0) AbbrevToUse = PtrAbbrev;
332      break;
333    }
334    case Type::FunctionTyID: {
335      FunctionType *FT = cast<FunctionType>(T);
336      // FUNCTION: [isvararg, attrid, retty, paramty x N]
337      Code = bitc::TYPE_CODE_FUNCTION_OLD;
338      TypeVals.push_back(FT->isVarArg());
339      TypeVals.push_back(0);  // FIXME: DEAD: remove in llvm 3.0
340      TypeVals.push_back(VE.getTypeID(FT->getReturnType()));
341      for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i)
342        TypeVals.push_back(VE.getTypeID(FT->getParamType(i)));
343      AbbrevToUse = FunctionAbbrev;
344      break;
345    }
346    case Type::StructTyID: {
347      StructType *ST = cast<StructType>(T);
348      // STRUCT: [ispacked, eltty x N]
349      TypeVals.push_back(ST->isPacked());
350      // Output all of the element types.
351      for (StructType::element_iterator I = ST->element_begin(),
352           E = ST->element_end(); I != E; ++I)
353        TypeVals.push_back(VE.getTypeID(*I));
354      AbbrevToUse = StructAbbrev;
355      break;
356    }
357    case Type::ArrayTyID: {
358      ArrayType *AT = cast<ArrayType>(T);
359      // ARRAY: [numelts, eltty]
360      Code = bitc::TYPE_CODE_ARRAY;
361      TypeVals.push_back(AT->getNumElements());
362      TypeVals.push_back(VE.getTypeID(AT->getElementType()));
363      AbbrevToUse = ArrayAbbrev;
364      break;
365    }
366    case Type::VectorTyID: {
367      VectorType *VT = cast<VectorType>(T);
368      // VECTOR [numelts, eltty]
369      Code = bitc::TYPE_CODE_VECTOR;
370      TypeVals.push_back(VT->getNumElements());
371      TypeVals.push_back(VE.getTypeID(VT->getElementType()));
372      break;
373    }
374    }
375
376    // Emit the finished record.
377    Stream.EmitRecord(Code, TypeVals, AbbrevToUse);
378    TypeVals.clear();
379  }
380
381  Stream.ExitBlock();
382
383  WriteTypeSymbolTable(VE, Stream);
384}
385
386static unsigned getEncodedLinkage(const GlobalValue *GV) {
387  switch (GV->getLinkage()) {
388  case GlobalValue::ExternalLinkage:                 return 0;
389  case GlobalValue::WeakAnyLinkage:                  return 1;
390  case GlobalValue::AppendingLinkage:                return 2;
391  case GlobalValue::InternalLinkage:                 return 3;
392  case GlobalValue::LinkOnceAnyLinkage:              return 4;
393  case GlobalValue::DLLImportLinkage:                return 5;
394  case GlobalValue::DLLExportLinkage:                return 6;
395  case GlobalValue::ExternalWeakLinkage:             return 7;
396  case GlobalValue::CommonLinkage:                   return 8;
397  case GlobalValue::PrivateLinkage:                  return 9;
398  case GlobalValue::WeakODRLinkage:                  return 10;
399  case GlobalValue::LinkOnceODRLinkage:              return 11;
400  case GlobalValue::AvailableExternallyLinkage:      return 12;
401  case GlobalValue::LinkerPrivateLinkage:            return 13;
402  case GlobalValue::LinkerPrivateWeakLinkage:        return 14;
403  case GlobalValue::LinkOnceODRAutoHideLinkage:      return 15;
404  }
405  llvm_unreachable("Invalid linkage");
406}
407
408static unsigned getEncodedVisibility(const GlobalValue *GV) {
409  switch (GV->getVisibility()) {
410  default: llvm_unreachable("Invalid visibility!");
411  case GlobalValue::DefaultVisibility:   return 0;
412  case GlobalValue::HiddenVisibility:    return 1;
413  case GlobalValue::ProtectedVisibility: return 2;
414  }
415}
416
417// Emit top-level description of module, including target triple, inline asm,
418// descriptors for global variables, and function prototype info.
419static void WriteModuleInfo(const Module *M,
420                            const llvm_2_9::ValueEnumerator &VE,
421                            BitstreamWriter &Stream) {
422  // Emit various pieces of data attached to a module.
423  if (!M->getTargetTriple().empty())
424    WriteStringRecord(bitc::MODULE_CODE_TRIPLE, M->getTargetTriple(),
425                      0/*TODO*/, Stream);
426  if (!M->getDataLayout().empty())
427    WriteStringRecord(bitc::MODULE_CODE_DATALAYOUT, M->getDataLayout(),
428                      0/*TODO*/, Stream);
429  if (!M->getModuleInlineAsm().empty())
430    WriteStringRecord(bitc::MODULE_CODE_ASM, M->getModuleInlineAsm(),
431                      0/*TODO*/, Stream);
432
433  // Emit information about sections and GC, computing how many there are. Also
434  // compute the maximum alignment value.
435  std::map<std::string, unsigned> SectionMap;
436  std::map<std::string, unsigned> GCMap;
437  unsigned MaxAlignment = 0;
438  unsigned MaxGlobalType = 0;
439  for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end();
440       GV != E; ++GV) {
441    MaxAlignment = std::max(MaxAlignment, GV->getAlignment());
442    MaxGlobalType = std::max(MaxGlobalType, VE.getTypeID(GV->getType()));
443
444    if (!GV->hasSection()) continue;
445    // Give section names unique ID's.
446    unsigned &Entry = SectionMap[GV->getSection()];
447    if (Entry != 0) continue;
448    WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, GV->getSection(),
449                      0/*TODO*/, Stream);
450    Entry = SectionMap.size();
451  }
452  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
453    MaxAlignment = std::max(MaxAlignment, F->getAlignment());
454    if (F->hasSection()) {
455      // Give section names unique ID's.
456      unsigned &Entry = SectionMap[F->getSection()];
457      if (!Entry) {
458        WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F->getSection(),
459                          0/*TODO*/, Stream);
460        Entry = SectionMap.size();
461      }
462    }
463    if (F->hasGC()) {
464      // Same for GC names.
465      unsigned &Entry = GCMap[F->getGC()];
466      if (!Entry) {
467        WriteStringRecord(bitc::MODULE_CODE_GCNAME, F->getGC(),
468                          0/*TODO*/, Stream);
469        Entry = GCMap.size();
470      }
471    }
472  }
473
474  // Emit abbrev for globals, now that we know # sections and max alignment.
475  unsigned SimpleGVarAbbrev = 0;
476  if (!M->global_empty()) {
477    // Add an abbrev for common globals with no visibility or thread localness.
478    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
479    Abbv->Add(BitCodeAbbrevOp(bitc::MODULE_CODE_GLOBALVAR));
480    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
481                              Log2_32_Ceil(MaxGlobalType+1)));
482    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));      // Constant.
483    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));        // Initializer.
484    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));      // Linkage.
485    if (MaxAlignment == 0)                                      // Alignment.
486      Abbv->Add(BitCodeAbbrevOp(0));
487    else {
488      unsigned MaxEncAlignment = Log2_32(MaxAlignment)+1;
489      Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
490                               Log2_32_Ceil(MaxEncAlignment+1)));
491    }
492    if (SectionMap.empty())                                    // Section.
493      Abbv->Add(BitCodeAbbrevOp(0));
494    else
495      Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
496                               Log2_32_Ceil(SectionMap.size()+1)));
497    // Don't bother emitting vis + thread local.
498    SimpleGVarAbbrev = Stream.EmitAbbrev(Abbv);
499  }
500
501  // Emit the global variable information.
502  SmallVector<unsigned, 64> Vals;
503  for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end();
504       GV != E; ++GV) {
505    unsigned AbbrevToUse = 0;
506
507    // GLOBALVAR: [type, isconst, initid,
508    //             linkage, alignment, section, visibility, threadlocal,
509    //             unnamed_addr]
510    Vals.push_back(VE.getTypeID(GV->getType()));
511    Vals.push_back(GV->isConstant());
512    Vals.push_back(GV->isDeclaration() ? 0 :
513                   (VE.getValueID(GV->getInitializer()) + 1));
514    Vals.push_back(getEncodedLinkage(GV));
515    Vals.push_back(Log2_32(GV->getAlignment())+1);
516    Vals.push_back(GV->hasSection() ? SectionMap[GV->getSection()] : 0);
517    if (GV->isThreadLocal() ||
518        GV->getVisibility() != GlobalValue::DefaultVisibility ||
519        GV->hasUnnamedAddr()) {
520      Vals.push_back(getEncodedVisibility(GV));
521      Vals.push_back(GV->isThreadLocal());
522      Vals.push_back(GV->hasUnnamedAddr());
523    } else {
524      AbbrevToUse = SimpleGVarAbbrev;
525    }
526
527    Stream.EmitRecord(bitc::MODULE_CODE_GLOBALVAR, Vals, AbbrevToUse);
528    Vals.clear();
529  }
530
531  // Emit the function proto information.
532  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
533    // FUNCTION:  [type, callingconv, isproto, paramattr,
534    //             linkage, alignment, section, visibility, gc, unnamed_addr]
535    Vals.push_back(VE.getTypeID(F->getType()));
536    Vals.push_back(F->getCallingConv());
537    Vals.push_back(F->isDeclaration());
538    Vals.push_back(getEncodedLinkage(F));
539    Vals.push_back(VE.getAttributeID(F->getAttributes()));
540    Vals.push_back(Log2_32(F->getAlignment())+1);
541    Vals.push_back(F->hasSection() ? SectionMap[F->getSection()] : 0);
542    Vals.push_back(getEncodedVisibility(F));
543    Vals.push_back(F->hasGC() ? GCMap[F->getGC()] : 0);
544    Vals.push_back(F->hasUnnamedAddr());
545
546    unsigned AbbrevToUse = 0;
547    Stream.EmitRecord(bitc::MODULE_CODE_FUNCTION, Vals, AbbrevToUse);
548    Vals.clear();
549  }
550
551  // Emit the alias information.
552  for (Module::const_alias_iterator AI = M->alias_begin(), E = M->alias_end();
553       AI != E; ++AI) {
554    Vals.push_back(VE.getTypeID(AI->getType()));
555    Vals.push_back(VE.getValueID(AI->getAliasee()));
556    Vals.push_back(getEncodedLinkage(AI));
557    Vals.push_back(getEncodedVisibility(AI));
558    unsigned AbbrevToUse = 0;
559    Stream.EmitRecord(bitc::MODULE_CODE_ALIAS, Vals, AbbrevToUse);
560    Vals.clear();
561  }
562}
563
564static uint64_t GetOptimizationFlags(const Value *V) {
565  uint64_t Flags = 0;
566
567  if (const OverflowingBinaryOperator *OBO =
568        dyn_cast<OverflowingBinaryOperator>(V)) {
569    if (OBO->hasNoSignedWrap())
570      Flags |= 1 << bitc::OBO_NO_SIGNED_WRAP;
571    if (OBO->hasNoUnsignedWrap())
572      Flags |= 1 << bitc::OBO_NO_UNSIGNED_WRAP;
573  } else if (const PossiblyExactOperator *PEO =
574               dyn_cast<PossiblyExactOperator>(V)) {
575    if (PEO->isExact())
576      Flags |= 1 << bitc::PEO_EXACT;
577  }
578
579  return Flags;
580}
581
582static void WriteMDNode(const MDNode *N,
583                        const llvm_2_9::ValueEnumerator &VE,
584                        BitstreamWriter &Stream,
585                        SmallVector<uint64_t, 64> &Record) {
586  for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
587    if (N->getOperand(i)) {
588      Record.push_back(VE.getTypeID(N->getOperand(i)->getType()));
589      Record.push_back(VE.getValueID(N->getOperand(i)));
590    } else {
591      Record.push_back(VE.getTypeID(Type::getVoidTy(N->getContext())));
592      Record.push_back(0);
593    }
594  }
595  unsigned MDCode = N->isFunctionLocal() ? METADATA_FN_NODE_2_7 :
596                                           METADATA_NODE_2_7;
597  Stream.EmitRecord(MDCode, Record, 0);
598  Record.clear();
599}
600
601static void WriteModuleMetadata(const Module *M,
602                                const llvm_2_9::ValueEnumerator &VE,
603                                BitstreamWriter &Stream) {
604  const llvm_2_9::ValueEnumerator::ValueList &Vals = VE.getMDValues();
605  bool StartedMetadataBlock = false;
606  unsigned MDSAbbrev = 0;
607  SmallVector<uint64_t, 64> Record;
608  for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
609
610    if (const MDNode *N = dyn_cast<MDNode>(Vals[i].first)) {
611      if (!N->isFunctionLocal() || !N->getFunction()) {
612        if (!StartedMetadataBlock) {
613          Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
614          StartedMetadataBlock = true;
615        }
616        WriteMDNode(N, VE, Stream, Record);
617      }
618    } else if (const MDString *MDS = dyn_cast<MDString>(Vals[i].first)) {
619      if (!StartedMetadataBlock)  {
620        Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
621
622        // Abbrev for METADATA_STRING.
623        BitCodeAbbrev *Abbv = new BitCodeAbbrev();
624        Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_STRING));
625        Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
626        Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
627        MDSAbbrev = Stream.EmitAbbrev(Abbv);
628        StartedMetadataBlock = true;
629      }
630
631      // Code: [strchar x N]
632      Record.append(MDS->begin(), MDS->end());
633
634      // Emit the finished record.
635      Stream.EmitRecord(bitc::METADATA_STRING, Record, MDSAbbrev);
636      Record.clear();
637    }
638  }
639
640  // Write named metadata.
641  for (Module::const_named_metadata_iterator I = M->named_metadata_begin(),
642       E = M->named_metadata_end(); I != E; ++I) {
643    const NamedMDNode *NMD = I;
644    if (!StartedMetadataBlock)  {
645      Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
646      StartedMetadataBlock = true;
647    }
648
649    // Write name.
650    StringRef Str = NMD->getName();
651    for (unsigned i = 0, e = Str.size(); i != e; ++i)
652      Record.push_back(Str[i]);
653    Stream.EmitRecord(bitc::METADATA_NAME, Record, 0/*TODO*/);
654    Record.clear();
655
656    // Write named metadata operands.
657    for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i)
658      Record.push_back(VE.getValueID(NMD->getOperand(i)));
659    Stream.EmitRecord(METADATA_NAMED_NODE_2_7, Record, 0);
660    Record.clear();
661  }
662
663  if (StartedMetadataBlock)
664    Stream.ExitBlock();
665}
666
667static void WriteFunctionLocalMetadata(const Function &F,
668                                       const llvm_2_9::ValueEnumerator &VE,
669                                       BitstreamWriter &Stream) {
670  bool StartedMetadataBlock = false;
671  SmallVector<uint64_t, 64> Record;
672  const SmallVector<const MDNode *, 8> &Vals = VE.getFunctionLocalMDValues();
673  for (unsigned i = 0, e = Vals.size(); i != e; ++i)
674    if (const MDNode *N = Vals[i])
675      if (N->isFunctionLocal() && N->getFunction() == &F) {
676        if (!StartedMetadataBlock) {
677          Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
678          StartedMetadataBlock = true;
679        }
680        WriteMDNode(N, VE, Stream, Record);
681      }
682
683  if (StartedMetadataBlock)
684    Stream.ExitBlock();
685}
686
687static void WriteMetadataAttachment(const Function &F,
688                                    const llvm_2_9::ValueEnumerator &VE,
689                                    BitstreamWriter &Stream) {
690  Stream.EnterSubblock(bitc::METADATA_ATTACHMENT_ID, 3);
691
692  SmallVector<uint64_t, 64> Record;
693
694  // Write metadata attachments
695  // METADATA_ATTACHMENT - [m x [value, [n x [id, mdnode]]]
696  SmallVector<std::pair<unsigned, MDNode*>, 4> MDs;
697
698  for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
699    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
700         I != E; ++I) {
701      MDs.clear();
702      I->getAllMetadataOtherThanDebugLoc(MDs);
703
704      // If no metadata, ignore instruction.
705      if (MDs.empty()) continue;
706
707      Record.push_back(VE.getInstructionID(I));
708
709      for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
710        Record.push_back(MDs[i].first);
711        Record.push_back(VE.getValueID(MDs[i].second));
712      }
713      Stream.EmitRecord(METADATA_ATTACHMENT_2_7, Record, 0);
714      Record.clear();
715    }
716
717  Stream.ExitBlock();
718}
719
720static void WriteModuleMetadataStore(const Module *M, BitstreamWriter &Stream) {
721  SmallVector<uint64_t, 64> Record;
722
723  // Write metadata kinds
724  // METADATA_KIND - [n x [id, name]]
725  SmallVector<StringRef, 4> Names;
726  M->getMDKindNames(Names);
727
728  if (Names.empty()) return;
729
730  Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
731
732  for (unsigned MDKindID = 0, e = Names.size(); MDKindID != e; ++MDKindID) {
733    Record.push_back(MDKindID);
734    StringRef KName = Names[MDKindID];
735    Record.append(KName.begin(), KName.end());
736
737    Stream.EmitRecord(bitc::METADATA_KIND, Record, 0);
738    Record.clear();
739  }
740
741  Stream.ExitBlock();
742}
743
744static void WriteConstants(unsigned FirstVal, unsigned LastVal,
745                           const llvm_2_9::ValueEnumerator &VE,
746                           BitstreamWriter &Stream, bool isGlobal) {
747  if (FirstVal == LastVal) return;
748
749  Stream.EnterSubblock(bitc::CONSTANTS_BLOCK_ID, 4);
750
751  unsigned AggregateAbbrev = 0;
752  unsigned String8Abbrev = 0;
753  unsigned CString7Abbrev = 0;
754  unsigned CString6Abbrev = 0;
755  // If this is a constant pool for the module, emit module-specific abbrevs.
756  if (isGlobal) {
757    // Abbrev for CST_CODE_AGGREGATE.
758    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
759    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_AGGREGATE));
760    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
761    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, Log2_32_Ceil(LastVal+1)));
762    AggregateAbbrev = Stream.EmitAbbrev(Abbv);
763
764    // Abbrev for CST_CODE_STRING.
765    Abbv = new BitCodeAbbrev();
766    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_STRING));
767    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
768    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
769    String8Abbrev = Stream.EmitAbbrev(Abbv);
770    // Abbrev for CST_CODE_CSTRING.
771    Abbv = new BitCodeAbbrev();
772    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
773    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
774    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
775    CString7Abbrev = Stream.EmitAbbrev(Abbv);
776    // Abbrev for CST_CODE_CSTRING.
777    Abbv = new BitCodeAbbrev();
778    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
779    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
780    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
781    CString6Abbrev = Stream.EmitAbbrev(Abbv);
782  }
783
784  SmallVector<uint64_t, 64> Record;
785
786  const llvm_2_9::ValueEnumerator::ValueList &Vals = VE.getValues();
787  Type *LastTy = 0;
788  for (unsigned i = FirstVal; i != LastVal; ++i) {
789    const Value *V = Vals[i].first;
790    // If we need to switch types, do so now.
791    if (V->getType() != LastTy) {
792      LastTy = V->getType();
793      Record.push_back(VE.getTypeID(LastTy));
794      Stream.EmitRecord(bitc::CST_CODE_SETTYPE, Record,
795                        CONSTANTS_SETTYPE_ABBREV);
796      Record.clear();
797    }
798
799    if (const InlineAsm *IA = dyn_cast<InlineAsm>(V)) {
800      Record.push_back(unsigned(IA->hasSideEffects()) |
801                       unsigned(IA->isAlignStack()) << 1);
802
803      // Add the asm string.
804      const std::string &AsmStr = IA->getAsmString();
805      Record.push_back(AsmStr.size());
806      for (unsigned i = 0, e = AsmStr.size(); i != e; ++i)
807        Record.push_back(AsmStr[i]);
808
809      // Add the constraint string.
810      const std::string &ConstraintStr = IA->getConstraintString();
811      Record.push_back(ConstraintStr.size());
812      for (unsigned i = 0, e = ConstraintStr.size(); i != e; ++i)
813        Record.push_back(ConstraintStr[i]);
814      Stream.EmitRecord(bitc::CST_CODE_INLINEASM, Record);
815      Record.clear();
816      continue;
817    }
818    const Constant *C = cast<Constant>(V);
819    unsigned Code = -1U;
820    unsigned AbbrevToUse = 0;
821    if (C->isNullValue()) {
822      Code = bitc::CST_CODE_NULL;
823    } else if (isa<UndefValue>(C)) {
824      Code = bitc::CST_CODE_UNDEF;
825    } else if (const ConstantInt *IV = dyn_cast<ConstantInt>(C)) {
826      if (IV->getBitWidth() <= 64) {
827        uint64_t V = IV->getSExtValue();
828        if ((int64_t)V >= 0)
829          Record.push_back(V << 1);
830        else
831          Record.push_back((-V << 1) | 1);
832        Code = bitc::CST_CODE_INTEGER;
833        AbbrevToUse = CONSTANTS_INTEGER_ABBREV;
834      } else {                             // Wide integers, > 64 bits in size.
835        // We have an arbitrary precision integer value to write whose
836        // bit width is > 64. However, in canonical unsigned integer
837        // format it is likely that the high bits are going to be zero.
838        // So, we only write the number of active words.
839        unsigned NWords = IV->getValue().getActiveWords();
840        const uint64_t *RawWords = IV->getValue().getRawData();
841        for (unsigned i = 0; i != NWords; ++i) {
842          int64_t V = RawWords[i];
843          if (V >= 0)
844            Record.push_back(V << 1);
845          else
846            Record.push_back((-V << 1) | 1);
847        }
848        Code = bitc::CST_CODE_WIDE_INTEGER;
849      }
850    } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
851      Code = bitc::CST_CODE_FLOAT;
852      Type *Ty = CFP->getType();
853      if (Ty->isFloatTy() || Ty->isDoubleTy()) {
854        Record.push_back(CFP->getValueAPF().bitcastToAPInt().getZExtValue());
855      } else if (Ty->isX86_FP80Ty()) {
856        // api needed to prevent premature destruction
857        // bits are not in the same order as a normal i80 APInt, compensate.
858        APInt api = CFP->getValueAPF().bitcastToAPInt();
859        const uint64_t *p = api.getRawData();
860        Record.push_back((p[1] << 48) | (p[0] >> 16));
861        Record.push_back(p[0] & 0xffffLL);
862      } else if (Ty->isFP128Ty() || Ty->isPPC_FP128Ty()) {
863        APInt api = CFP->getValueAPF().bitcastToAPInt();
864        const uint64_t *p = api.getRawData();
865        Record.push_back(p[0]);
866        Record.push_back(p[1]);
867      } else {
868        assert (0 && "Unknown FP type!");
869      }
870    } else if (isa<ConstantDataSequential>(C) &&
871               cast<ConstantDataSequential>(C)->isString()) {
872      const ConstantDataSequential *Str = cast<ConstantDataSequential>(C);
873      // Emit constant strings specially.
874      unsigned NumElts = Str->getNumElements();
875      // If this is a null-terminated string, use the denser CSTRING encoding.
876      if (Str->isCString()) {
877        Code = bitc::CST_CODE_CSTRING;
878        --NumElts;  // Don't encode the null, which isn't allowed by char6.
879      } else {
880        Code = bitc::CST_CODE_STRING;
881        AbbrevToUse = String8Abbrev;
882      }
883      bool isCStr7 = Code == bitc::CST_CODE_CSTRING;
884      bool isCStrChar6 = Code == bitc::CST_CODE_CSTRING;
885      for (unsigned i = 0; i != NumElts; ++i) {
886        unsigned char V = Str->getElementAsInteger(i);
887        Record.push_back(V);
888        isCStr7 &= (V & 128) == 0;
889        if (isCStrChar6)
890          isCStrChar6 = BitCodeAbbrevOp::isChar6(V);
891      }
892
893      if (isCStrChar6)
894        AbbrevToUse = CString6Abbrev;
895      else if (isCStr7)
896        AbbrevToUse = CString7Abbrev;
897    } else if (const ConstantDataSequential *CDS =
898                  dyn_cast<ConstantDataSequential>(C)) {
899      // We must replace ConstantDataSequential's representation with the
900      // legacy ConstantArray/ConstantVector/ConstantStruct version.
901      // ValueEnumerator is similarly modified to mark the appropriate
902      // Constants as used (so they are emitted).
903      Code = bitc::CST_CODE_AGGREGATE;
904      for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i)
905        Record.push_back(VE.getValueID(CDS->getElementAsConstant(i)));
906      AbbrevToUse = AggregateAbbrev;
907    } else if (isa<ConstantArray>(C) || isa<ConstantStruct>(C) ||
908               isa<ConstantVector>(C)) {
909      Code = bitc::CST_CODE_AGGREGATE;
910      for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i)
911        Record.push_back(VE.getValueID(C->getOperand(i)));
912      AbbrevToUse = AggregateAbbrev;
913    } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
914      switch (CE->getOpcode()) {
915      default:
916        if (Instruction::isCast(CE->getOpcode())) {
917          Code = bitc::CST_CODE_CE_CAST;
918          Record.push_back(GetEncodedCastOpcode(CE->getOpcode()));
919          Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
920          Record.push_back(VE.getValueID(C->getOperand(0)));
921          AbbrevToUse = CONSTANTS_CE_CAST_Abbrev;
922        } else {
923          assert(CE->getNumOperands() == 2 && "Unknown constant expr!");
924          Code = bitc::CST_CODE_CE_BINOP;
925          Record.push_back(GetEncodedBinaryOpcode(CE->getOpcode()));
926          Record.push_back(VE.getValueID(C->getOperand(0)));
927          Record.push_back(VE.getValueID(C->getOperand(1)));
928          uint64_t Flags = GetOptimizationFlags(CE);
929          if (Flags != 0)
930            Record.push_back(Flags);
931        }
932        break;
933      case Instruction::GetElementPtr:
934        Code = bitc::CST_CODE_CE_GEP;
935        if (cast<GEPOperator>(C)->isInBounds())
936          Code = bitc::CST_CODE_CE_INBOUNDS_GEP;
937        for (unsigned i = 0, e = CE->getNumOperands(); i != e; ++i) {
938          Record.push_back(VE.getTypeID(C->getOperand(i)->getType()));
939          Record.push_back(VE.getValueID(C->getOperand(i)));
940        }
941        break;
942      case Instruction::Select:
943        Code = bitc::CST_CODE_CE_SELECT;
944        Record.push_back(VE.getValueID(C->getOperand(0)));
945        Record.push_back(VE.getValueID(C->getOperand(1)));
946        Record.push_back(VE.getValueID(C->getOperand(2)));
947        break;
948      case Instruction::ExtractElement:
949        Code = bitc::CST_CODE_CE_EXTRACTELT;
950        Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
951        Record.push_back(VE.getValueID(C->getOperand(0)));
952        Record.push_back(VE.getValueID(C->getOperand(1)));
953        break;
954      case Instruction::InsertElement:
955        Code = bitc::CST_CODE_CE_INSERTELT;
956        Record.push_back(VE.getValueID(C->getOperand(0)));
957        Record.push_back(VE.getValueID(C->getOperand(1)));
958        Record.push_back(VE.getValueID(C->getOperand(2)));
959        break;
960      case Instruction::ShuffleVector:
961        // If the return type and argument types are the same, this is a
962        // standard shufflevector instruction.  If the types are different,
963        // then the shuffle is widening or truncating the input vectors, and
964        // the argument type must also be encoded.
965        if (C->getType() == C->getOperand(0)->getType()) {
966          Code = bitc::CST_CODE_CE_SHUFFLEVEC;
967        } else {
968          Code = bitc::CST_CODE_CE_SHUFVEC_EX;
969          Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
970        }
971        Record.push_back(VE.getValueID(C->getOperand(0)));
972        Record.push_back(VE.getValueID(C->getOperand(1)));
973        Record.push_back(VE.getValueID(C->getOperand(2)));
974        break;
975      case Instruction::ICmp:
976      case Instruction::FCmp:
977        Code = bitc::CST_CODE_CE_CMP;
978        Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
979        Record.push_back(VE.getValueID(C->getOperand(0)));
980        Record.push_back(VE.getValueID(C->getOperand(1)));
981        Record.push_back(CE->getPredicate());
982        break;
983      }
984    } else if (const BlockAddress *BA = dyn_cast<BlockAddress>(C)) {
985      Code = bitc::CST_CODE_BLOCKADDRESS;
986      Record.push_back(VE.getTypeID(BA->getFunction()->getType()));
987      Record.push_back(VE.getValueID(BA->getFunction()));
988      Record.push_back(VE.getGlobalBasicBlockID(BA->getBasicBlock()));
989    } else {
990#ifndef NDEBUG
991      C->dump();
992#endif
993      llvm_unreachable("Unknown constant!");
994    }
995    Stream.EmitRecord(Code, Record, AbbrevToUse);
996    Record.clear();
997  }
998
999  Stream.ExitBlock();
1000}
1001
1002static void WriteModuleConstants(const llvm_2_9::ValueEnumerator &VE,
1003                                 BitstreamWriter &Stream) {
1004  const llvm_2_9::ValueEnumerator::ValueList &Vals = VE.getValues();
1005
1006  // Find the first constant to emit, which is the first non-globalvalue value.
1007  // We know globalvalues have been emitted by WriteModuleInfo.
1008  for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
1009    if (!isa<GlobalValue>(Vals[i].first)) {
1010      WriteConstants(i, Vals.size(), VE, Stream, true);
1011      return;
1012    }
1013  }
1014}
1015
1016/// PushValueAndType - The file has to encode both the value and type id for
1017/// many values, because we need to know what type to create for forward
1018/// references.  However, most operands are not forward references, so this type
1019/// field is not needed.
1020///
1021/// This function adds V's value ID to Vals.  If the value ID is higher than the
1022/// instruction ID, then it is a forward reference, and it also includes the
1023/// type ID.
1024static bool PushValueAndType(const Value *V, unsigned InstID,
1025                             SmallVector<unsigned, 64> &Vals,
1026                             llvm_2_9::ValueEnumerator &VE) {
1027  unsigned ValID = VE.getValueID(V);
1028  Vals.push_back(ValID);
1029  if (ValID >= InstID) {
1030    Vals.push_back(VE.getTypeID(V->getType()));
1031    return true;
1032  }
1033  return false;
1034}
1035
1036/// WriteInstruction - Emit an instruction to the specified stream.
1037static void WriteInstruction(const Instruction &I, unsigned InstID,
1038                             llvm_2_9::ValueEnumerator &VE,
1039                             BitstreamWriter &Stream,
1040                             SmallVector<unsigned, 64> &Vals) {
1041  unsigned Code = 0;
1042  unsigned AbbrevToUse = 0;
1043  VE.setInstructionID(&I);
1044  switch (I.getOpcode()) {
1045  default:
1046    if (Instruction::isCast(I.getOpcode())) {
1047      Code = bitc::FUNC_CODE_INST_CAST;
1048      if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1049        AbbrevToUse = FUNCTION_INST_CAST_ABBREV;
1050      Vals.push_back(VE.getTypeID(I.getType()));
1051      Vals.push_back(GetEncodedCastOpcode(I.getOpcode()));
1052    } else {
1053      assert(isa<BinaryOperator>(I) && "Unknown instruction!");
1054      Code = bitc::FUNC_CODE_INST_BINOP;
1055      if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1056        AbbrevToUse = FUNCTION_INST_BINOP_ABBREV;
1057      Vals.push_back(VE.getValueID(I.getOperand(1)));
1058      Vals.push_back(GetEncodedBinaryOpcode(I.getOpcode()));
1059      uint64_t Flags = GetOptimizationFlags(&I);
1060      if (Flags != 0) {
1061        if (AbbrevToUse == FUNCTION_INST_BINOP_ABBREV)
1062          AbbrevToUse = FUNCTION_INST_BINOP_FLAGS_ABBREV;
1063        Vals.push_back(Flags);
1064      }
1065    }
1066    break;
1067
1068  case Instruction::GetElementPtr:
1069    Code = bitc::FUNC_CODE_INST_GEP;
1070    if (cast<GEPOperator>(&I)->isInBounds())
1071      Code = bitc::FUNC_CODE_INST_INBOUNDS_GEP;
1072    for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1073      PushValueAndType(I.getOperand(i), InstID, Vals, VE);
1074    break;
1075  case Instruction::ExtractValue: {
1076    Code = bitc::FUNC_CODE_INST_EXTRACTVAL;
1077    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1078    const ExtractValueInst *EVI = cast<ExtractValueInst>(&I);
1079    for (const unsigned *i = EVI->idx_begin(), *e = EVI->idx_end(); i != e; ++i)
1080      Vals.push_back(*i);
1081    break;
1082  }
1083  case Instruction::InsertValue: {
1084    Code = bitc::FUNC_CODE_INST_INSERTVAL;
1085    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1086    PushValueAndType(I.getOperand(1), InstID, Vals, VE);
1087    const InsertValueInst *IVI = cast<InsertValueInst>(&I);
1088    for (const unsigned *i = IVI->idx_begin(), *e = IVI->idx_end(); i != e; ++i)
1089      Vals.push_back(*i);
1090    break;
1091  }
1092  case Instruction::Select:
1093    Code = bitc::FUNC_CODE_INST_VSELECT;
1094    PushValueAndType(I.getOperand(1), InstID, Vals, VE);
1095    Vals.push_back(VE.getValueID(I.getOperand(2)));
1096    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1097    break;
1098  case Instruction::ExtractElement:
1099    Code = bitc::FUNC_CODE_INST_EXTRACTELT;
1100    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1101    Vals.push_back(VE.getValueID(I.getOperand(1)));
1102    break;
1103  case Instruction::InsertElement:
1104    Code = bitc::FUNC_CODE_INST_INSERTELT;
1105    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1106    Vals.push_back(VE.getValueID(I.getOperand(1)));
1107    Vals.push_back(VE.getValueID(I.getOperand(2)));
1108    break;
1109  case Instruction::ShuffleVector:
1110    Code = bitc::FUNC_CODE_INST_SHUFFLEVEC;
1111    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1112    Vals.push_back(VE.getValueID(I.getOperand(1)));
1113    Vals.push_back(VE.getValueID(I.getOperand(2)));
1114    break;
1115  case Instruction::ICmp:
1116  case Instruction::FCmp:
1117    // compare returning Int1Ty or vector of Int1Ty
1118    Code = bitc::FUNC_CODE_INST_CMP2;
1119    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1120    Vals.push_back(VE.getValueID(I.getOperand(1)));
1121    Vals.push_back(cast<CmpInst>(I).getPredicate());
1122    break;
1123
1124  case Instruction::Ret:
1125    {
1126      Code = bitc::FUNC_CODE_INST_RET;
1127      unsigned NumOperands = I.getNumOperands();
1128      if (NumOperands == 0)
1129        AbbrevToUse = FUNCTION_INST_RET_VOID_ABBREV;
1130      else if (NumOperands == 1) {
1131        if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1132          AbbrevToUse = FUNCTION_INST_RET_VAL_ABBREV;
1133      } else {
1134        for (unsigned i = 0, e = NumOperands; i != e; ++i)
1135          PushValueAndType(I.getOperand(i), InstID, Vals, VE);
1136      }
1137    }
1138    break;
1139  case Instruction::Br:
1140    {
1141      Code = bitc::FUNC_CODE_INST_BR;
1142      const BranchInst &II = cast<BranchInst>(I);
1143      Vals.push_back(VE.getValueID(II.getSuccessor(0)));
1144      if (II.isConditional()) {
1145        Vals.push_back(VE.getValueID(II.getSuccessor(1)));
1146        Vals.push_back(VE.getValueID(II.getCondition()));
1147      }
1148    }
1149    break;
1150  case Instruction::Switch:
1151    {
1152      Code = bitc::FUNC_CODE_INST_SWITCH;
1153      const SwitchInst &SI = cast<SwitchInst>(I);
1154
1155      Vals.push_back(VE.getTypeID(SI.getCondition()->getType()));
1156      Vals.push_back(VE.getValueID(SI.getCondition()));
1157      Vals.push_back(VE.getValueID(SI.getDefaultDest()));
1158      for (SwitchInst::ConstCaseIt i = SI.case_begin(), e = SI.case_end();
1159           i != e; ++i) {
1160        const IntegersSubset& CaseRanges = i.getCaseValueEx();
1161
1162        if (CaseRanges.isSingleNumber()) {
1163          Vals.push_back(VE.getValueID(CaseRanges.getSingleNumber(0).toConstantInt()));
1164          Vals.push_back(VE.getValueID(i.getCaseSuccessor()));
1165        } else if (CaseRanges.isSingleNumbersOnly()) {
1166          for (unsigned ri = 0, rn = CaseRanges.getNumItems();
1167               ri != rn; ++ri) {
1168            Vals.push_back(VE.getValueID(CaseRanges.getSingleNumber(ri).toConstantInt()));
1169            Vals.push_back(VE.getValueID(i.getCaseSuccessor()));
1170          }
1171        } else {
1172          llvm_unreachable("Not single number?");
1173        }
1174      }
1175    }
1176    break;
1177  case Instruction::IndirectBr:
1178    Code = bitc::FUNC_CODE_INST_INDIRECTBR;
1179    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1180    for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1181      Vals.push_back(VE.getValueID(I.getOperand(i)));
1182    break;
1183
1184  case Instruction::Invoke: {
1185    const InvokeInst *II = cast<InvokeInst>(&I);
1186    const Value *Callee(II->getCalledValue());
1187    PointerType *PTy = cast<PointerType>(Callee->getType());
1188    FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1189    Code = bitc::FUNC_CODE_INST_INVOKE;
1190
1191    Vals.push_back(VE.getAttributeID(II->getAttributes()));
1192    Vals.push_back(II->getCallingConv());
1193    Vals.push_back(VE.getValueID(II->getNormalDest()));
1194    Vals.push_back(VE.getValueID(II->getUnwindDest()));
1195    PushValueAndType(Callee, InstID, Vals, VE);
1196
1197    // Emit value #'s for the fixed parameters.
1198    for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
1199      Vals.push_back(VE.getValueID(I.getOperand(i)));  // fixed param.
1200
1201    // Emit type/value pairs for varargs params.
1202    if (FTy->isVarArg()) {
1203      for (unsigned i = FTy->getNumParams(), e = I.getNumOperands()-3;
1204           i != e; ++i)
1205        PushValueAndType(I.getOperand(i), InstID, Vals, VE); // vararg
1206    }
1207    break;
1208  }
1209  case Instruction::Unreachable:
1210    Code = bitc::FUNC_CODE_INST_UNREACHABLE;
1211    AbbrevToUse = FUNCTION_INST_UNREACHABLE_ABBREV;
1212    break;
1213
1214  case Instruction::PHI: {
1215    const PHINode &PN = cast<PHINode>(I);
1216    Code = bitc::FUNC_CODE_INST_PHI;
1217    Vals.push_back(VE.getTypeID(PN.getType()));
1218    for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
1219      Vals.push_back(VE.getValueID(PN.getIncomingValue(i)));
1220      Vals.push_back(VE.getValueID(PN.getIncomingBlock(i)));
1221    }
1222    break;
1223  }
1224
1225  case Instruction::Alloca:
1226    Code = bitc::FUNC_CODE_INST_ALLOCA;
1227    Vals.push_back(VE.getTypeID(I.getType()));
1228    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1229    Vals.push_back(VE.getValueID(I.getOperand(0))); // size.
1230    Vals.push_back(Log2_32(cast<AllocaInst>(I).getAlignment())+1);
1231    break;
1232
1233  case Instruction::Load:
1234    Code = bitc::FUNC_CODE_INST_LOAD;
1235    if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))  // ptr
1236      AbbrevToUse = FUNCTION_INST_LOAD_ABBREV;
1237
1238    Vals.push_back(Log2_32(cast<LoadInst>(I).getAlignment())+1);
1239    Vals.push_back(cast<LoadInst>(I).isVolatile());
1240    break;
1241  case Instruction::Store:
1242    Code = bitc::FUNC_CODE_INST_STORE;
1243    PushValueAndType(I.getOperand(1), InstID, Vals, VE);  // ptrty + ptr
1244    Vals.push_back(VE.getValueID(I.getOperand(0)));       // val.
1245    Vals.push_back(Log2_32(cast<StoreInst>(I).getAlignment())+1);
1246    Vals.push_back(cast<StoreInst>(I).isVolatile());
1247    break;
1248  case Instruction::Call: {
1249    const CallInst &CI = cast<CallInst>(I);
1250    PointerType *PTy = cast<PointerType>(CI.getCalledValue()->getType());
1251    FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1252
1253    Code = FUNC_CODE_INST_CALL_2_7;
1254
1255    Vals.push_back(VE.getAttributeID(CI.getAttributes()));
1256    Vals.push_back((CI.getCallingConv() << 1) | unsigned(CI.isTailCall()));
1257    PushValueAndType(CI.getCalledValue(), InstID, Vals, VE);  // Callee
1258
1259    // Emit value #'s for the fixed parameters.
1260    for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
1261      Vals.push_back(VE.getValueID(CI.getArgOperand(i)));  // fixed param.
1262
1263    // Emit type/value pairs for varargs params.
1264    if (FTy->isVarArg()) {
1265      for (unsigned i = FTy->getNumParams(), e = CI.getNumArgOperands();
1266           i != e; ++i)
1267        PushValueAndType(CI.getArgOperand(i), InstID, Vals, VE);  // varargs
1268    }
1269    break;
1270  }
1271  case Instruction::VAArg:
1272    Code = bitc::FUNC_CODE_INST_VAARG;
1273    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));   // valistty
1274    Vals.push_back(VE.getValueID(I.getOperand(0))); // valist.
1275    Vals.push_back(VE.getTypeID(I.getType())); // restype.
1276    break;
1277  }
1278
1279  Stream.EmitRecord(Code, Vals, AbbrevToUse);
1280  Vals.clear();
1281}
1282
1283// Emit names for globals/functions etc.
1284static void WriteValueSymbolTable(const ValueSymbolTable &VST,
1285                                  const llvm_2_9::ValueEnumerator &VE,
1286                                  BitstreamWriter &Stream) {
1287  if (VST.empty()) return;
1288  Stream.EnterSubblock(bitc::VALUE_SYMTAB_BLOCK_ID, 4);
1289
1290  // FIXME: Set up the abbrev, we know how many values there are!
1291  // FIXME: We know if the type names can use 7-bit ascii.
1292  SmallVector<unsigned, 64> NameVals;
1293
1294  for (ValueSymbolTable::const_iterator SI = VST.begin(), SE = VST.end();
1295       SI != SE; ++SI) {
1296
1297    const ValueName &Name = *SI;
1298
1299    // Figure out the encoding to use for the name.
1300    bool is7Bit = true;
1301    bool isChar6 = true;
1302    for (const char *C = Name.getKeyData(), *E = C+Name.getKeyLength();
1303         C != E; ++C) {
1304      if (isChar6)
1305        isChar6 = BitCodeAbbrevOp::isChar6(*C);
1306      if ((unsigned char)*C & 128) {
1307        is7Bit = false;
1308        break;  // don't bother scanning the rest.
1309      }
1310    }
1311
1312    unsigned AbbrevToUse = VST_ENTRY_8_ABBREV;
1313
1314    // VST_ENTRY:   [valueid, namechar x N]
1315    // VST_BBENTRY: [bbid, namechar x N]
1316    unsigned Code;
1317    if (isa<BasicBlock>(SI->getValue())) {
1318      Code = bitc::VST_CODE_BBENTRY;
1319      if (isChar6)
1320        AbbrevToUse = VST_BBENTRY_6_ABBREV;
1321    } else {
1322      Code = bitc::VST_CODE_ENTRY;
1323      if (isChar6)
1324        AbbrevToUse = VST_ENTRY_6_ABBREV;
1325      else if (is7Bit)
1326        AbbrevToUse = VST_ENTRY_7_ABBREV;
1327    }
1328
1329    NameVals.push_back(VE.getValueID(SI->getValue()));
1330    for (const char *P = Name.getKeyData(),
1331         *E = Name.getKeyData()+Name.getKeyLength(); P != E; ++P)
1332      NameVals.push_back((unsigned char)*P);
1333
1334    // Emit the finished record.
1335    Stream.EmitRecord(Code, NameVals, AbbrevToUse);
1336    NameVals.clear();
1337  }
1338  Stream.ExitBlock();
1339}
1340
1341/// WriteFunction - Emit a function body to the module stream.
1342static void WriteFunction(const Function &F, llvm_2_9::ValueEnumerator &VE,
1343                          BitstreamWriter &Stream) {
1344  Stream.EnterSubblock(bitc::FUNCTION_BLOCK_ID, 4);
1345  VE.incorporateFunction(F);
1346
1347  SmallVector<unsigned, 64> Vals;
1348
1349  // Emit the number of basic blocks, so the reader can create them ahead of
1350  // time.
1351  Vals.push_back(VE.getBasicBlocks().size());
1352  Stream.EmitRecord(bitc::FUNC_CODE_DECLAREBLOCKS, Vals);
1353  Vals.clear();
1354
1355  // If there are function-local constants, emit them now.
1356  unsigned CstStart, CstEnd;
1357  VE.getFunctionConstantRange(CstStart, CstEnd);
1358  WriteConstants(CstStart, CstEnd, VE, Stream, false);
1359
1360  // If there is function-local metadata, emit it now.
1361  WriteFunctionLocalMetadata(F, VE, Stream);
1362
1363  // Keep a running idea of what the instruction ID is.
1364  unsigned InstID = CstEnd;
1365
1366  bool NeedsMetadataAttachment = false;
1367
1368  DebugLoc LastDL;
1369
1370  // Finally, emit all the instructions, in order.
1371  for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
1372    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
1373         I != E; ++I) {
1374      WriteInstruction(*I, InstID, VE, Stream, Vals);
1375
1376      if (!I->getType()->isVoidTy())
1377        ++InstID;
1378
1379      // If the instruction has metadata, write a metadata attachment later.
1380      NeedsMetadataAttachment |= I->hasMetadataOtherThanDebugLoc();
1381
1382      // If the instruction has a debug location, emit it.
1383      DebugLoc DL = I->getDebugLoc();
1384      if (DL.isUnknown()) {
1385        // nothing todo.
1386      } else if (DL == LastDL) {
1387        // Just repeat the same debug loc as last time.
1388        Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC_AGAIN, Vals);
1389      } else {
1390        MDNode *Scope, *IA;
1391        DL.getScopeAndInlinedAt(Scope, IA, I->getContext());
1392
1393        Vals.push_back(DL.getLine());
1394        Vals.push_back(DL.getCol());
1395        Vals.push_back(Scope ? VE.getValueID(Scope)+1 : 0);
1396        Vals.push_back(IA ? VE.getValueID(IA)+1 : 0);
1397        Stream.EmitRecord(FUNC_CODE_DEBUG_LOC_2_7, Vals);
1398        Vals.clear();
1399
1400        LastDL = DL;
1401      }
1402    }
1403
1404  // Emit names for all the instructions etc.
1405  WriteValueSymbolTable(F.getValueSymbolTable(), VE, Stream);
1406
1407  if (NeedsMetadataAttachment)
1408    WriteMetadataAttachment(F, VE, Stream);
1409  VE.purgeFunction();
1410  Stream.ExitBlock();
1411}
1412
1413// Emit blockinfo, which defines the standard abbreviations etc.
1414static void WriteBlockInfo(const llvm_2_9::ValueEnumerator &VE,
1415                           BitstreamWriter &Stream) {
1416  // We only want to emit block info records for blocks that have multiple
1417  // instances: CONSTANTS_BLOCK, FUNCTION_BLOCK and VALUE_SYMTAB_BLOCK.  Other
1418  // blocks can defined their abbrevs inline.
1419  Stream.EnterBlockInfoBlock(2);
1420
1421  { // 8-bit fixed-width VST_ENTRY/VST_BBENTRY strings.
1422    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1423    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3));
1424    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1425    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1426    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
1427    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1428                                   Abbv) != VST_ENTRY_8_ABBREV)
1429      llvm_unreachable("Unexpected abbrev ordering!");
1430  }
1431
1432  { // 7-bit fixed width VST_ENTRY strings.
1433    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1434    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1435    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1436    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1437    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
1438    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1439                                   Abbv) != VST_ENTRY_7_ABBREV)
1440      llvm_unreachable("Unexpected abbrev ordering!");
1441  }
1442  { // 6-bit char6 VST_ENTRY strings.
1443    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1444    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1445    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1446    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1447    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1448    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1449                                   Abbv) != VST_ENTRY_6_ABBREV)
1450      llvm_unreachable("Unexpected abbrev ordering!");
1451  }
1452  { // 6-bit char6 VST_BBENTRY strings.
1453    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1454    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_BBENTRY));
1455    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1456    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1457    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1458    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1459                                   Abbv) != VST_BBENTRY_6_ABBREV)
1460      llvm_unreachable("Unexpected abbrev ordering!");
1461  }
1462
1463
1464
1465  { // SETTYPE abbrev for CONSTANTS_BLOCK.
1466    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1467    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_SETTYPE));
1468    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1469                              Log2_32_Ceil(VE.getTypes().size()+1)));
1470    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1471                                   Abbv) != CONSTANTS_SETTYPE_ABBREV)
1472      llvm_unreachable("Unexpected abbrev ordering!");
1473  }
1474
1475  { // INTEGER abbrev for CONSTANTS_BLOCK.
1476    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1477    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_INTEGER));
1478    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1479    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1480                                   Abbv) != CONSTANTS_INTEGER_ABBREV)
1481      llvm_unreachable("Unexpected abbrev ordering!");
1482  }
1483
1484  { // CE_CAST abbrev for CONSTANTS_BLOCK.
1485    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1486    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CE_CAST));
1487    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // cast opc
1488    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // typeid
1489                              Log2_32_Ceil(VE.getTypes().size()+1)));
1490    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));    // value id
1491
1492    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1493                                   Abbv) != CONSTANTS_CE_CAST_Abbrev)
1494      llvm_unreachable("Unexpected abbrev ordering!");
1495  }
1496  { // NULL abbrev for CONSTANTS_BLOCK.
1497    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1498    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_NULL));
1499    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1500                                   Abbv) != CONSTANTS_NULL_Abbrev)
1501      llvm_unreachable("Unexpected abbrev ordering!");
1502  }
1503
1504  // FIXME: This should only use space for first class types!
1505
1506  { // INST_LOAD abbrev for FUNCTION_BLOCK.
1507    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1508    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_LOAD));
1509    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Ptr
1510    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4)); // Align
1511    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // volatile
1512    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1513                                   Abbv) != FUNCTION_INST_LOAD_ABBREV)
1514      llvm_unreachable("Unexpected abbrev ordering!");
1515  }
1516  { // INST_BINOP abbrev for FUNCTION_BLOCK.
1517    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1518    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1519    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1520    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1521    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1522    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1523                                   Abbv) != FUNCTION_INST_BINOP_ABBREV)
1524      llvm_unreachable("Unexpected abbrev ordering!");
1525  }
1526  { // INST_BINOP_FLAGS abbrev for FUNCTION_BLOCK.
1527    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1528    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1529    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1530    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1531    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1532    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7)); // flags
1533    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1534                                   Abbv) != FUNCTION_INST_BINOP_FLAGS_ABBREV)
1535      llvm_unreachable("Unexpected abbrev ordering!");
1536  }
1537  { // INST_CAST abbrev for FUNCTION_BLOCK.
1538    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1539    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_CAST));
1540    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));    // OpVal
1541    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // dest ty
1542                              Log2_32_Ceil(VE.getTypes().size()+1)));
1543    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // opc
1544    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1545                                   Abbv) != FUNCTION_INST_CAST_ABBREV)
1546      llvm_unreachable("Unexpected abbrev ordering!");
1547  }
1548
1549  { // INST_RET abbrev for FUNCTION_BLOCK.
1550    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1551    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1552    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1553                                   Abbv) != FUNCTION_INST_RET_VOID_ABBREV)
1554      llvm_unreachable("Unexpected abbrev ordering!");
1555  }
1556  { // INST_RET abbrev for FUNCTION_BLOCK.
1557    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1558    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1559    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ValID
1560    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1561                                   Abbv) != FUNCTION_INST_RET_VAL_ABBREV)
1562      llvm_unreachable("Unexpected abbrev ordering!");
1563  }
1564  { // INST_UNREACHABLE abbrev for FUNCTION_BLOCK.
1565    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1566    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_UNREACHABLE));
1567    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1568                                   Abbv) != FUNCTION_INST_UNREACHABLE_ABBREV)
1569      llvm_unreachable("Unexpected abbrev ordering!");
1570  }
1571
1572  Stream.ExitBlock();
1573}
1574
1575
1576/// WriteModule - Emit the specified module to the bitstream.
1577static void WriteModule(const Module *M, BitstreamWriter &Stream) {
1578  Stream.EnterSubblock(bitc::MODULE_BLOCK_ID, 3);
1579
1580  // Emit the version number if it is non-zero.
1581  if (CurVersion) {
1582    SmallVector<unsigned, 1> Vals;
1583    Vals.push_back(CurVersion);
1584    Stream.EmitRecord(bitc::MODULE_CODE_VERSION, Vals);
1585  }
1586
1587  // Analyze the module, enumerating globals, functions, etc.
1588  llvm_2_9::ValueEnumerator VE(M);
1589
1590  // Emit blockinfo, which defines the standard abbreviations etc.
1591  WriteBlockInfo(VE, Stream);
1592
1593  // Emit information about parameter attributes.
1594  WriteAttributeTable(VE, Stream);
1595
1596  // Emit information describing all of the types in the module.
1597  WriteTypeTable(VE, Stream);
1598
1599  // Emit top-level description of module, including target triple, inline asm,
1600  // descriptors for global variables, and function prototype info.
1601  WriteModuleInfo(M, VE, Stream);
1602
1603  // Emit constants.
1604  WriteModuleConstants(VE, Stream);
1605
1606  // Emit metadata.
1607  WriteModuleMetadata(M, VE, Stream);
1608
1609  // Emit function bodies.
1610  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F)
1611    if (!F->isDeclaration())
1612      WriteFunction(*F, VE, Stream);
1613
1614  // Emit metadata.
1615  WriteModuleMetadataStore(M, Stream);
1616
1617  // Emit names for globals/functions etc.
1618  WriteValueSymbolTable(M->getValueSymbolTable(), VE, Stream);
1619
1620  Stream.ExitBlock();
1621}
1622
1623/// EmitDarwinBCHeader - If generating a bc file on darwin, we have to emit a
1624/// header and trailer to make it compatible with the system archiver.  To do
1625/// this we emit the following header, and then emit a trailer that pads the
1626/// file out to be a multiple of 16 bytes.
1627///
1628/// struct bc_header {
1629///   uint32_t Magic;         // 0x0B17C0DE
1630///   uint32_t Version;       // Version, currently always 0.
1631///   uint32_t BitcodeOffset; // Offset to traditional bitcode file.
1632///   uint32_t BitcodeSize;   // Size of traditional bitcode file.
1633///   uint32_t CPUType;       // CPU specifier.
1634///   ... potentially more later ...
1635/// };
1636enum {
1637  DarwinBCSizeFieldOffset = 3*4, // Offset to bitcode_size.
1638  DarwinBCHeaderSize = 5*4
1639};
1640
1641static void WriteInt32ToBuffer(uint32_t Value, SmallVectorImpl<char> &Buffer,
1642                               uint32_t &Position) {
1643  Buffer[Position + 0] = (unsigned char) (Value >>  0);
1644  Buffer[Position + 1] = (unsigned char) (Value >>  8);
1645  Buffer[Position + 2] = (unsigned char) (Value >> 16);
1646  Buffer[Position + 3] = (unsigned char) (Value >> 24);
1647  Position += 4;
1648}
1649
1650static void EmitDarwinBCHeaderAndTrailer(SmallVectorImpl<char> &Buffer,
1651                                         const Triple &TT) {
1652  unsigned CPUType = ~0U;
1653
1654  // Match x86_64-*, i[3-9]86-*, powerpc-*, powerpc64-*, arm-*, thumb-*,
1655  // armv[0-9]-*, thumbv[0-9]-*, armv5te-*, or armv6t2-*. The CPUType is a magic
1656  // number from /usr/include/mach/machine.h.  It is ok to reproduce the
1657  // specific constants here because they are implicitly part of the Darwin ABI.
1658  enum {
1659    DARWIN_CPU_ARCH_ABI64      = 0x01000000,
1660    DARWIN_CPU_TYPE_X86        = 7,
1661    DARWIN_CPU_TYPE_ARM        = 12,
1662    DARWIN_CPU_TYPE_POWERPC    = 18
1663  };
1664
1665  Triple::ArchType Arch = TT.getArch();
1666  if (Arch == Triple::x86_64)
1667    CPUType = DARWIN_CPU_TYPE_X86 | DARWIN_CPU_ARCH_ABI64;
1668  else if (Arch == Triple::x86)
1669    CPUType = DARWIN_CPU_TYPE_X86;
1670  else if (Arch == Triple::ppc)
1671    CPUType = DARWIN_CPU_TYPE_POWERPC;
1672  else if (Arch == Triple::ppc64)
1673    CPUType = DARWIN_CPU_TYPE_POWERPC | DARWIN_CPU_ARCH_ABI64;
1674  else if (Arch == Triple::arm || Arch == Triple::thumb)
1675    CPUType = DARWIN_CPU_TYPE_ARM;
1676
1677  // Traditional Bitcode starts after header.
1678  assert(Buffer.size() >= DarwinBCHeaderSize &&
1679         "Expected header size to be reserved");
1680  unsigned BCOffset = DarwinBCHeaderSize;
1681  unsigned BCSize = Buffer.size()-DarwinBCHeaderSize;
1682
1683  // Write the magic and version.
1684  unsigned Position = 0;
1685  WriteInt32ToBuffer(0x0B17C0DE , Buffer, Position);
1686  WriteInt32ToBuffer(0          , Buffer, Position); // Version.
1687  WriteInt32ToBuffer(BCOffset   , Buffer, Position);
1688  WriteInt32ToBuffer(BCSize     , Buffer, Position);
1689  WriteInt32ToBuffer(CPUType    , Buffer, Position);
1690
1691  // If the file is not a multiple of 16 bytes, insert dummy padding.
1692  while (Buffer.size() & 15)
1693    Buffer.push_back(0);
1694}
1695
1696/// WriteBitcodeToFile - Write the specified module to the specified output
1697/// stream.
1698void llvm_2_9::WriteBitcodeToFile(const Module *M, raw_ostream &Out) {
1699  SmallVector<char, 1024> Buffer;
1700  Buffer.reserve(256*1024);
1701
1702  // If this is darwin or another generic macho target, reserve space for the
1703  // header.
1704  Triple TT(M->getTargetTriple());
1705  if (TT.isOSDarwin())
1706    Buffer.insert(Buffer.begin(), DarwinBCHeaderSize, 0);
1707
1708  // Emit the module into the buffer.
1709  {
1710    BitstreamWriter Stream(Buffer);
1711
1712    // Emit the file header.
1713    Stream.Emit((unsigned)'B', 8);
1714    Stream.Emit((unsigned)'C', 8);
1715    Stream.Emit(0x0, 4);
1716    Stream.Emit(0xC, 4);
1717    Stream.Emit(0xE, 4);
1718    Stream.Emit(0xD, 4);
1719
1720    // Emit the module.
1721    WriteModule(M, Stream);
1722  }
1723
1724  if (TT.isOSDarwin())
1725    EmitDarwinBCHeaderAndTrailer(Buffer, TT);
1726
1727  // Write the generated bitstream to "Out".
1728  Out.write((char*)&Buffer.front(), Buffer.size());
1729}
1730