BitcodeWriter.cpp revision 9937d116e09feb32d46a4c76eca1be6afcd3bed5 
1//===--- Bitcode/Writer/BitcodeWriter.cpp - Bitcode Writer ----------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// Bitcode writer implementation.
11//
12//===----------------------------------------------------------------------===//
13
14#include "ReaderWriter_2_9_func.h"
15#include "llvm/Bitcode/BitstreamWriter.h"
16#include "llvm/Bitcode/LLVMBitCodes.h"
17#include "ValueEnumerator.h"
18#include "llvm/Constants.h"
19#include "llvm/DerivedTypes.h"
20#include "llvm/InlineAsm.h"
21#include "llvm/Instructions.h"
22#include "llvm/Module.h"
23#include "llvm/Operator.h"
24#include "llvm/ValueSymbolTable.h"
25#include "llvm/ADT/Triple.h"
26#include "llvm/Support/ErrorHandling.h"
27#include "llvm/Support/MathExtras.h"
28#include "llvm/Support/raw_ostream.h"
29#include "llvm/Support/Program.h"
30#include <cctype>
31#include <map>
32using namespace llvm;
33
34/// These are manifest constants used by the bitcode writer. They do not need to
35/// be kept in sync with the reader, but need to be consistent within this file.
36enum {
37  CurVersion = 0,
38
39  // VALUE_SYMTAB_BLOCK abbrev id's.
40  VST_ENTRY_8_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
41  VST_ENTRY_7_ABBREV,
42  VST_ENTRY_6_ABBREV,
43  VST_BBENTRY_6_ABBREV,
44
45  // CONSTANTS_BLOCK abbrev id's.
46  CONSTANTS_SETTYPE_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
47  CONSTANTS_INTEGER_ABBREV,
48  CONSTANTS_CE_CAST_Abbrev,
49  CONSTANTS_NULL_Abbrev,
50
51  // FUNCTION_BLOCK abbrev id's.
52  FUNCTION_INST_LOAD_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
53  FUNCTION_INST_BINOP_ABBREV,
54  FUNCTION_INST_BINOP_FLAGS_ABBREV,
55  FUNCTION_INST_CAST_ABBREV,
56  FUNCTION_INST_RET_VOID_ABBREV,
57  FUNCTION_INST_RET_VAL_ABBREV,
58  FUNCTION_INST_UNREACHABLE_ABBREV
59};
60
61static unsigned GetEncodedCastOpcode(unsigned Opcode) {
62  switch (Opcode) {
63  default: llvm_unreachable("Unknown cast instruction!");
64  case Instruction::Trunc   : return bitc::CAST_TRUNC;
65  case Instruction::ZExt    : return bitc::CAST_ZEXT;
66  case Instruction::SExt    : return bitc::CAST_SEXT;
67  case Instruction::FPToUI  : return bitc::CAST_FPTOUI;
68  case Instruction::FPToSI  : return bitc::CAST_FPTOSI;
69  case Instruction::UIToFP  : return bitc::CAST_UITOFP;
70  case Instruction::SIToFP  : return bitc::CAST_SITOFP;
71  case Instruction::FPTrunc : return bitc::CAST_FPTRUNC;
72  case Instruction::FPExt   : return bitc::CAST_FPEXT;
73  case Instruction::PtrToInt: return bitc::CAST_PTRTOINT;
74  case Instruction::IntToPtr: return bitc::CAST_INTTOPTR;
75  case Instruction::BitCast : return bitc::CAST_BITCAST;
76  }
77}
78
79static unsigned GetEncodedBinaryOpcode(unsigned Opcode) {
80  switch (Opcode) {
81  default: llvm_unreachable("Unknown binary instruction!");
82  case Instruction::Add:
83  case Instruction::FAdd: return bitc::BINOP_ADD;
84  case Instruction::Sub:
85  case Instruction::FSub: return bitc::BINOP_SUB;
86  case Instruction::Mul:
87  case Instruction::FMul: return bitc::BINOP_MUL;
88  case Instruction::UDiv: return bitc::BINOP_UDIV;
89  case Instruction::FDiv:
90  case Instruction::SDiv: return bitc::BINOP_SDIV;
91  case Instruction::URem: return bitc::BINOP_UREM;
92  case Instruction::FRem:
93  case Instruction::SRem: return bitc::BINOP_SREM;
94  case Instruction::Shl:  return bitc::BINOP_SHL;
95  case Instruction::LShr: return bitc::BINOP_LSHR;
96  case Instruction::AShr: return bitc::BINOP_ASHR;
97  case Instruction::And:  return bitc::BINOP_AND;
98  case Instruction::Or:   return bitc::BINOP_OR;
99  case Instruction::Xor:  return bitc::BINOP_XOR;
100  }
101}
102
103static unsigned GetEncodedRMWOperation(AtomicRMWInst::BinOp Op) {
104  switch (Op) {
105  default: llvm_unreachable("Unknown RMW operation!");
106  case AtomicRMWInst::Xchg: return bitc::RMW_XCHG;
107  case AtomicRMWInst::Add: return bitc::RMW_ADD;
108  case AtomicRMWInst::Sub: return bitc::RMW_SUB;
109  case AtomicRMWInst::And: return bitc::RMW_AND;
110  case AtomicRMWInst::Nand: return bitc::RMW_NAND;
111  case AtomicRMWInst::Or: return bitc::RMW_OR;
112  case AtomicRMWInst::Xor: return bitc::RMW_XOR;
113  case AtomicRMWInst::Max: return bitc::RMW_MAX;
114  case AtomicRMWInst::Min: return bitc::RMW_MIN;
115  case AtomicRMWInst::UMax: return bitc::RMW_UMAX;
116  case AtomicRMWInst::UMin: return bitc::RMW_UMIN;
117  }
118}
119
120static unsigned GetEncodedOrdering(AtomicOrdering Ordering) {
121  switch (Ordering) {
122  default: llvm_unreachable("Unknown atomic ordering");
123  case NotAtomic: return bitc::ORDERING_NOTATOMIC;
124  case Unordered: return bitc::ORDERING_UNORDERED;
125  case Monotonic: return bitc::ORDERING_MONOTONIC;
126  case Acquire: return bitc::ORDERING_ACQUIRE;
127  case Release: return bitc::ORDERING_RELEASE;
128  case AcquireRelease: return bitc::ORDERING_ACQREL;
129  case SequentiallyConsistent: return bitc::ORDERING_SEQCST;
130  }
131}
132
133static unsigned GetEncodedSynchScope(SynchronizationScope SynchScope) {
134  switch (SynchScope) {
135  default: llvm_unreachable("Unknown synchronization scope");
136  case SingleThread: return bitc::SYNCHSCOPE_SINGLETHREAD;
137  case CrossThread: return bitc::SYNCHSCOPE_CROSSTHREAD;
138  }
139}
140
141static void WriteStringRecord(unsigned Code, StringRef Str,
142                              unsigned AbbrevToUse, BitstreamWriter &Stream) {
143  SmallVector<unsigned, 64> Vals;
144
145  // Code: [strchar x N]
146  for (unsigned i = 0, e = Str.size(); i != e; ++i) {
147    if (AbbrevToUse && !BitCodeAbbrevOp::isChar6(Str[i]))
148      AbbrevToUse = 0;
149    Vals.push_back(Str[i]);
150  }
151
152  // Emit the finished record.
153  Stream.EmitRecord(Code, Vals, AbbrevToUse);
154}
155
156// Emit information about parameter attributes.
157static void WriteAttributeTable(const llvm_2_9_func::ValueEnumerator &VE,
158                                BitstreamWriter &Stream) {
159  const std::vector<AttrListPtr> &Attrs = VE.getAttributes();
160  if (Attrs.empty()) return;
161
162  Stream.EnterSubblock(bitc::PARAMATTR_BLOCK_ID, 3);
163
164  SmallVector<uint64_t, 64> Record;
165  for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
166    const AttrListPtr &A = Attrs[i];
167    for (unsigned i = 0, e = A.getNumSlots(); i != e; ++i) {
168      const AttributeWithIndex &PAWI = A.getSlot(i);
169      Record.push_back(PAWI.Index);
170
171      // FIXME: remove in LLVM 3.0
172      // Store the alignment in the bitcode as a 16-bit raw value instead of a
173      // 5-bit log2 encoded value. Shift the bits above the alignment up by
174      // 11 bits.
175      uint64_t FauxAttr = PAWI.Attrs.Raw() & 0xffff;
176      if (PAWI.Attrs & Attribute::Alignment)
177        FauxAttr |= (1ull<<16)<<
178            (((PAWI.Attrs & Attribute::Alignment).Raw()-1) >> 16);
179      FauxAttr |= (PAWI.Attrs.Raw() & (0x3FFull << 21)) << 11;
180
181      Record.push_back(FauxAttr);
182    }
183
184    Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY, Record);
185    Record.clear();
186  }
187
188  Stream.ExitBlock();
189}
190
191/// WriteTypeTable - Write out the type table for a module.
192static void WriteTypeTable(const llvm_2_9_func::ValueEnumerator &VE,
193                           BitstreamWriter &Stream) {
194  const llvm_2_9_func::ValueEnumerator::TypeList &TypeList = VE.getTypes();
195
196  Stream.EnterSubblock(bitc::TYPE_BLOCK_ID_NEW, 4 /*count from # abbrevs */);
197  SmallVector<uint64_t, 64> TypeVals;
198
199  // Abbrev for TYPE_CODE_POINTER.
200  BitCodeAbbrev *Abbv = new BitCodeAbbrev();
201  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_POINTER));
202  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
203                            Log2_32_Ceil(VE.getTypes().size()+1)));
204  Abbv->Add(BitCodeAbbrevOp(0));  // Addrspace = 0
205  unsigned PtrAbbrev = Stream.EmitAbbrev(Abbv);
206
207  // Abbrev for TYPE_CODE_FUNCTION.
208  Abbv = new BitCodeAbbrev();
209  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_FUNCTION_OLD));
210  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // isvararg
211  Abbv->Add(BitCodeAbbrevOp(0));  // FIXME: DEAD value, remove in LLVM 3.0
212  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
213  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
214                            Log2_32_Ceil(VE.getTypes().size()+1)));
215  unsigned FunctionAbbrev = Stream.EmitAbbrev(Abbv);
216
217  // Abbrev for TYPE_CODE_STRUCT_ANON.
218  Abbv = new BitCodeAbbrev();
219  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_ANON));
220  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // ispacked
221  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
222  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
223                            Log2_32_Ceil(VE.getTypes().size()+1)));
224  unsigned StructAnonAbbrev = Stream.EmitAbbrev(Abbv);
225
226  // Abbrev for TYPE_CODE_STRUCT_NAME.
227  Abbv = new BitCodeAbbrev();
228  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_NAME));
229  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
230  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
231  unsigned StructNameAbbrev = Stream.EmitAbbrev(Abbv);
232
233  // Abbrev for TYPE_CODE_STRUCT_NAMED.
234  Abbv = new BitCodeAbbrev();
235  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_NAMED));
236  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // ispacked
237  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
238  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
239                            Log2_32_Ceil(VE.getTypes().size()+1)));
240  unsigned StructNamedAbbrev = Stream.EmitAbbrev(Abbv);
241
242  // Abbrev for TYPE_CODE_ARRAY.
243  Abbv = new BitCodeAbbrev();
244  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_ARRAY));
245  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // size
246  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
247                            Log2_32_Ceil(VE.getTypes().size()+1)));
248  unsigned ArrayAbbrev = Stream.EmitAbbrev(Abbv);
249
250  // Emit an entry count so the reader can reserve space.
251  TypeVals.push_back(TypeList.size());
252  Stream.EmitRecord(bitc::TYPE_CODE_NUMENTRY, TypeVals);
253  TypeVals.clear();
254
255  // Loop over all of the types, emitting each in turn.
256  for (unsigned i = 0, e = TypeList.size(); i != e; ++i) {
257    Type *T = TypeList[i];
258    int AbbrevToUse = 0;
259    unsigned Code = 0;
260
261    switch (T->getTypeID()) {
262    default: llvm_unreachable("Unknown type!");
263    case Type::VoidTyID:      Code = bitc::TYPE_CODE_VOID;   break;
264    case Type::FloatTyID:     Code = bitc::TYPE_CODE_FLOAT;  break;
265    case Type::DoubleTyID:    Code = bitc::TYPE_CODE_DOUBLE; break;
266    case Type::X86_FP80TyID:  Code = bitc::TYPE_CODE_X86_FP80; break;
267    case Type::FP128TyID:     Code = bitc::TYPE_CODE_FP128; break;
268    case Type::PPC_FP128TyID: Code = bitc::TYPE_CODE_PPC_FP128; break;
269    case Type::LabelTyID:     Code = bitc::TYPE_CODE_LABEL;  break;
270    case Type::MetadataTyID:  Code = bitc::TYPE_CODE_METADATA; break;
271    case Type::X86_MMXTyID:   Code = bitc::TYPE_CODE_X86_MMX; break;
272    case Type::IntegerTyID:
273      // INTEGER: [width]
274      Code = bitc::TYPE_CODE_INTEGER;
275      TypeVals.push_back(cast<IntegerType>(T)->getBitWidth());
276      break;
277    case Type::PointerTyID: {
278      PointerType *PTy = cast<PointerType>(T);
279      // POINTER: [pointee type, address space]
280      Code = bitc::TYPE_CODE_POINTER;
281      TypeVals.push_back(VE.getTypeID(PTy->getElementType()));
282      unsigned AddressSpace = PTy->getAddressSpace();
283      TypeVals.push_back(AddressSpace);
284      if (AddressSpace == 0) AbbrevToUse = PtrAbbrev;
285      break;
286    }
287    case Type::FunctionTyID: {
288      FunctionType *FT = cast<FunctionType>(T);
289      // FUNCTION: [isvararg, attrid, retty, paramty x N]
290      Code = bitc::TYPE_CODE_FUNCTION_OLD;
291      TypeVals.push_back(FT->isVarArg());
292      TypeVals.push_back(0);  // FIXME: DEAD: remove in llvm 3.0
293      TypeVals.push_back(VE.getTypeID(FT->getReturnType()));
294      for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i)
295        TypeVals.push_back(VE.getTypeID(FT->getParamType(i)));
296      AbbrevToUse = FunctionAbbrev;
297      break;
298    }
299    case Type::StructTyID: {
300      StructType *ST = cast<StructType>(T);
301      // STRUCT: [ispacked, eltty x N]
302      TypeVals.push_back(ST->isPacked());
303      // Output all of the element types.
304      for (StructType::element_iterator I = ST->element_begin(),
305           E = ST->element_end(); I != E; ++I)
306        TypeVals.push_back(VE.getTypeID(*I));
307
308      if (ST->isLiteral()) {
309        Code = bitc::TYPE_CODE_STRUCT_ANON;
310        AbbrevToUse = StructAnonAbbrev;
311      } else {
312        if (ST->isOpaque()) {
313          Code = bitc::TYPE_CODE_OPAQUE;
314        } else {
315          Code = bitc::TYPE_CODE_STRUCT_NAMED;
316          AbbrevToUse = StructNamedAbbrev;
317        }
318
319        // Emit the name if it is present.
320        if (!ST->getName().empty())
321          WriteStringRecord(bitc::TYPE_CODE_STRUCT_NAME, ST->getName(),
322                            StructNameAbbrev, Stream);
323      }
324      break;
325    }
326    case Type::ArrayTyID: {
327      ArrayType *AT = cast<ArrayType>(T);
328      // ARRAY: [numelts, eltty]
329      Code = bitc::TYPE_CODE_ARRAY;
330      TypeVals.push_back(AT->getNumElements());
331      TypeVals.push_back(VE.getTypeID(AT->getElementType()));
332      AbbrevToUse = ArrayAbbrev;
333      break;
334    }
335    case Type::VectorTyID: {
336      VectorType *VT = cast<VectorType>(T);
337      // VECTOR [numelts, eltty]
338      Code = bitc::TYPE_CODE_VECTOR;
339      TypeVals.push_back(VT->getNumElements());
340      TypeVals.push_back(VE.getTypeID(VT->getElementType()));
341      break;
342    }
343    }
344
345    // Emit the finished record.
346    Stream.EmitRecord(Code, TypeVals, AbbrevToUse);
347    TypeVals.clear();
348  }
349
350  Stream.ExitBlock();
351}
352
353static unsigned getEncodedLinkage(const GlobalValue *GV) {
354  switch (GV->getLinkage()) {
355  default: llvm_unreachable("Invalid linkage!");
356  case GlobalValue::ExternalLinkage:                 return 0;
357  case GlobalValue::WeakAnyLinkage:                  return 1;
358  case GlobalValue::AppendingLinkage:                return 2;
359  case GlobalValue::InternalLinkage:                 return 3;
360  case GlobalValue::LinkOnceAnyLinkage:              return 4;
361  case GlobalValue::DLLImportLinkage:                return 5;
362  case GlobalValue::DLLExportLinkage:                return 6;
363  case GlobalValue::ExternalWeakLinkage:             return 7;
364  case GlobalValue::CommonLinkage:                   return 8;
365  case GlobalValue::PrivateLinkage:                  return 9;
366  case GlobalValue::WeakODRLinkage:                  return 10;
367  case GlobalValue::LinkOnceODRLinkage:              return 11;
368  case GlobalValue::AvailableExternallyLinkage:      return 12;
369  case GlobalValue::LinkerPrivateLinkage:            return 13;
370  case GlobalValue::LinkerPrivateWeakLinkage:        return 14;
371  case GlobalValue::LinkerPrivateWeakDefAutoLinkage: return 15;
372  }
373}
374
375static unsigned getEncodedVisibility(const GlobalValue *GV) {
376  switch (GV->getVisibility()) {
377  default: llvm_unreachable("Invalid visibility!");
378  case GlobalValue::DefaultVisibility:   return 0;
379  case GlobalValue::HiddenVisibility:    return 1;
380  case GlobalValue::ProtectedVisibility: return 2;
381  }
382}
383
384// Emit top-level description of module, including target triple, inline asm,
385// descriptors for global variables, and function prototype info.
386static void WriteModuleInfo(const Module *M,
387                            const llvm_2_9_func::ValueEnumerator &VE,
388                            BitstreamWriter &Stream) {
389  // Emit the list of dependent libraries for the Module.
390  for (Module::lib_iterator I = M->lib_begin(), E = M->lib_end(); I != E; ++I)
391    WriteStringRecord(bitc::MODULE_CODE_DEPLIB, *I, 0/*TODO*/, Stream);
392
393  // Emit various pieces of data attached to a module.
394  if (!M->getTargetTriple().empty())
395    WriteStringRecord(bitc::MODULE_CODE_TRIPLE, M->getTargetTriple(),
396                      0/*TODO*/, Stream);
397  if (!M->getDataLayout().empty())
398    WriteStringRecord(bitc::MODULE_CODE_DATALAYOUT, M->getDataLayout(),
399                      0/*TODO*/, Stream);
400  if (!M->getModuleInlineAsm().empty())
401    WriteStringRecord(bitc::MODULE_CODE_ASM, M->getModuleInlineAsm(),
402                      0/*TODO*/, Stream);
403
404  // Emit information about sections and GC, computing how many there are. Also
405  // compute the maximum alignment value.
406  std::map<std::string, unsigned> SectionMap;
407  std::map<std::string, unsigned> GCMap;
408  unsigned MaxAlignment = 0;
409  unsigned MaxGlobalType = 0;
410  for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end();
411       GV != E; ++GV) {
412    MaxAlignment = std::max(MaxAlignment, GV->getAlignment());
413    MaxGlobalType = std::max(MaxGlobalType, VE.getTypeID(GV->getType()));
414    if (GV->hasSection()) {
415      // Give section names unique ID's.
416      unsigned &Entry = SectionMap[GV->getSection()];
417      if (!Entry) {
418        WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, GV->getSection(),
419                          0/*TODO*/, Stream);
420        Entry = SectionMap.size();
421      }
422    }
423  }
424  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
425    MaxAlignment = std::max(MaxAlignment, F->getAlignment());
426    if (F->hasSection()) {
427      // Give section names unique ID's.
428      unsigned &Entry = SectionMap[F->getSection()];
429      if (!Entry) {
430        WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F->getSection(),
431                          0/*TODO*/, Stream);
432        Entry = SectionMap.size();
433      }
434    }
435    if (F->hasGC()) {
436      // Same for GC names.
437      unsigned &Entry = GCMap[F->getGC()];
438      if (!Entry) {
439        WriteStringRecord(bitc::MODULE_CODE_GCNAME, F->getGC(),
440                          0/*TODO*/, Stream);
441        Entry = GCMap.size();
442      }
443    }
444  }
445
446  // Emit abbrev for globals, now that we know # sections and max alignment.
447  unsigned SimpleGVarAbbrev = 0;
448  if (!M->global_empty()) {
449    // Add an abbrev for common globals with no visibility or thread localness.
450    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
451    Abbv->Add(BitCodeAbbrevOp(bitc::MODULE_CODE_GLOBALVAR));
452    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
453                              Log2_32_Ceil(MaxGlobalType+1)));
454    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));      // Constant.
455    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));        // Initializer.
456    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));      // Linkage.
457    if (MaxAlignment == 0)                                      // Alignment.
458      Abbv->Add(BitCodeAbbrevOp(0));
459    else {
460      unsigned MaxEncAlignment = Log2_32(MaxAlignment)+1;
461      Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
462                               Log2_32_Ceil(MaxEncAlignment+1)));
463    }
464    if (SectionMap.empty())                                    // Section.
465      Abbv->Add(BitCodeAbbrevOp(0));
466    else
467      Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
468                               Log2_32_Ceil(SectionMap.size()+1)));
469    // Don't bother emitting vis + thread local.
470    SimpleGVarAbbrev = Stream.EmitAbbrev(Abbv);
471  }
472
473  // Emit the global variable information.
474  SmallVector<unsigned, 64> Vals;
475  for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end();
476       GV != E; ++GV) {
477    unsigned AbbrevToUse = 0;
478
479    // GLOBALVAR: [type, isconst, initid,
480    //             linkage, alignment, section, visibility, threadlocal,
481    //             unnamed_addr]
482    Vals.push_back(VE.getTypeID(GV->getType()));
483    Vals.push_back(GV->isConstant());
484    Vals.push_back(GV->isDeclaration() ? 0 :
485                   (VE.getValueID(GV->getInitializer()) + 1));
486    Vals.push_back(getEncodedLinkage(GV));
487    Vals.push_back(Log2_32(GV->getAlignment())+1);
488    Vals.push_back(GV->hasSection() ? SectionMap[GV->getSection()] : 0);
489    if (GV->isThreadLocal() ||
490        GV->getVisibility() != GlobalValue::DefaultVisibility ||
491        GV->hasUnnamedAddr()) {
492      Vals.push_back(getEncodedVisibility(GV));
493      Vals.push_back(GV->isThreadLocal());
494      Vals.push_back(GV->hasUnnamedAddr());
495    } else {
496      AbbrevToUse = SimpleGVarAbbrev;
497    }
498
499    Stream.EmitRecord(bitc::MODULE_CODE_GLOBALVAR, Vals, AbbrevToUse);
500    Vals.clear();
501  }
502
503  // Emit the function proto information.
504  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
505    // FUNCTION:  [type, callingconv, isproto, paramattr,
506    //             linkage, alignment, section, visibility, gc, unnamed_addr]
507    Vals.push_back(VE.getTypeID(F->getType()));
508    Vals.push_back(F->getCallingConv());
509    Vals.push_back(F->isDeclaration());
510    Vals.push_back(getEncodedLinkage(F));
511    Vals.push_back(VE.getAttributeID(F->getAttributes()));
512    Vals.push_back(Log2_32(F->getAlignment())+1);
513    Vals.push_back(F->hasSection() ? SectionMap[F->getSection()] : 0);
514    Vals.push_back(getEncodedVisibility(F));
515    Vals.push_back(F->hasGC() ? GCMap[F->getGC()] : 0);
516    Vals.push_back(F->hasUnnamedAddr());
517
518    unsigned AbbrevToUse = 0;
519    Stream.EmitRecord(bitc::MODULE_CODE_FUNCTION, Vals, AbbrevToUse);
520    Vals.clear();
521  }
522
523  // Emit the alias information.
524  for (Module::const_alias_iterator AI = M->alias_begin(), E = M->alias_end();
525       AI != E; ++AI) {
526    Vals.push_back(VE.getTypeID(AI->getType()));
527    Vals.push_back(VE.getValueID(AI->getAliasee()));
528    Vals.push_back(getEncodedLinkage(AI));
529    Vals.push_back(getEncodedVisibility(AI));
530    unsigned AbbrevToUse = 0;
531    Stream.EmitRecord(bitc::MODULE_CODE_ALIAS, Vals, AbbrevToUse);
532    Vals.clear();
533  }
534}
535
536static uint64_t GetOptimizationFlags(const Value *V) {
537  uint64_t Flags = 0;
538
539  if (const OverflowingBinaryOperator *OBO =
540        dyn_cast<OverflowingBinaryOperator>(V)) {
541    if (OBO->hasNoSignedWrap())
542      Flags |= 1 << bitc::OBO_NO_SIGNED_WRAP;
543    if (OBO->hasNoUnsignedWrap())
544      Flags |= 1 << bitc::OBO_NO_UNSIGNED_WRAP;
545  } else if (const PossiblyExactOperator *PEO =
546               dyn_cast<PossiblyExactOperator>(V)) {
547    if (PEO->isExact())
548      Flags |= 1 << bitc::PEO_EXACT;
549  }
550
551  return Flags;
552}
553
554static void WriteMDNode(const MDNode *N,
555                        const llvm_2_9_func::ValueEnumerator &VE,
556                        BitstreamWriter &Stream,
557                        SmallVector<uint64_t, 64> &Record) {
558  for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
559    if (N->getOperand(i)) {
560      Record.push_back(VE.getTypeID(N->getOperand(i)->getType()));
561      Record.push_back(VE.getValueID(N->getOperand(i)));
562    } else {
563      Record.push_back(VE.getTypeID(Type::getVoidTy(N->getContext())));
564      Record.push_back(0);
565    }
566  }
567  unsigned MDCode = N->isFunctionLocal() ? bitc::METADATA_FN_NODE :
568                                           bitc::METADATA_NODE;
569  Stream.EmitRecord(MDCode, Record, 0);
570  Record.clear();
571}
572
573static void WriteModuleMetadata(const Module *M,
574                                const llvm_2_9_func::ValueEnumerator &VE,
575                                BitstreamWriter &Stream) {
576  const llvm_2_9_func::ValueEnumerator::ValueList &Vals = VE.getMDValues();
577  bool StartedMetadataBlock = false;
578  unsigned MDSAbbrev = 0;
579  SmallVector<uint64_t, 64> Record;
580  for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
581
582    if (const MDNode *N = dyn_cast<MDNode>(Vals[i].first)) {
583      if (!N->isFunctionLocal() || !N->getFunction()) {
584        if (!StartedMetadataBlock) {
585          Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
586          StartedMetadataBlock = true;
587        }
588        WriteMDNode(N, VE, Stream, Record);
589      }
590    } else if (const MDString *MDS = dyn_cast<MDString>(Vals[i].first)) {
591      if (!StartedMetadataBlock)  {
592        Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
593
594        // Abbrev for METADATA_STRING.
595        BitCodeAbbrev *Abbv = new BitCodeAbbrev();
596        Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_STRING));
597        Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
598        Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
599        MDSAbbrev = Stream.EmitAbbrev(Abbv);
600        StartedMetadataBlock = true;
601      }
602
603      // Code: [strchar x N]
604      Record.append(MDS->begin(), MDS->end());
605
606      // Emit the finished record.
607      Stream.EmitRecord(bitc::METADATA_STRING, Record, MDSAbbrev);
608      Record.clear();
609    }
610  }
611
612  // Write named metadata.
613  for (Module::const_named_metadata_iterator I = M->named_metadata_begin(),
614       E = M->named_metadata_end(); I != E; ++I) {
615    const NamedMDNode *NMD = I;
616    if (!StartedMetadataBlock)  {
617      Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
618      StartedMetadataBlock = true;
619    }
620
621    // Write name.
622    StringRef Str = NMD->getName();
623    for (unsigned i = 0, e = Str.size(); i != e; ++i)
624      Record.push_back(Str[i]);
625    Stream.EmitRecord(bitc::METADATA_NAME, Record, 0/*TODO*/);
626    Record.clear();
627
628    // Write named metadata operands.
629    for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i)
630      Record.push_back(VE.getValueID(NMD->getOperand(i)));
631    Stream.EmitRecord(bitc::METADATA_NAMED_NODE, Record, 0);
632    Record.clear();
633  }
634
635  if (StartedMetadataBlock)
636    Stream.ExitBlock();
637}
638
639static void WriteFunctionLocalMetadata(const Function &F,
640                                       const llvm_2_9_func::ValueEnumerator &VE,
641                                       BitstreamWriter &Stream) {
642  bool StartedMetadataBlock = false;
643  SmallVector<uint64_t, 64> Record;
644  const SmallVector<const MDNode *, 8> &Vals = VE.getFunctionLocalMDValues();
645  for (unsigned i = 0, e = Vals.size(); i != e; ++i)
646    if (const MDNode *N = Vals[i])
647      if (N->isFunctionLocal() && N->getFunction() == &F) {
648        if (!StartedMetadataBlock) {
649          Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
650          StartedMetadataBlock = true;
651        }
652        WriteMDNode(N, VE, Stream, Record);
653      }
654
655  if (StartedMetadataBlock)
656    Stream.ExitBlock();
657}
658
659static void WriteMetadataAttachment(const Function &F,
660                                    const llvm_2_9_func::ValueEnumerator &VE,
661                                    BitstreamWriter &Stream) {
662  Stream.EnterSubblock(bitc::METADATA_ATTACHMENT_ID, 3);
663
664  SmallVector<uint64_t, 64> Record;
665
666  // Write metadata attachments
667  // METADATA_ATTACHMENT - [m x [value, [n x [id, mdnode]]]
668  SmallVector<std::pair<unsigned, MDNode*>, 4> MDs;
669
670  for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
671    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
672         I != E; ++I) {
673      MDs.clear();
674      I->getAllMetadataOtherThanDebugLoc(MDs);
675
676      // If no metadata, ignore instruction.
677      if (MDs.empty()) continue;
678
679      Record.push_back(VE.getInstructionID(I));
680
681      for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
682        Record.push_back(MDs[i].first);
683        Record.push_back(VE.getValueID(MDs[i].second));
684      }
685      Stream.EmitRecord(bitc::METADATA_ATTACHMENT, Record, 0);
686      Record.clear();
687    }
688
689  Stream.ExitBlock();
690}
691
692static void WriteModuleMetadataStore(const Module *M, BitstreamWriter &Stream) {
693  SmallVector<uint64_t, 64> Record;
694
695  // Write metadata kinds
696  // METADATA_KIND - [n x [id, name]]
697  SmallVector<StringRef, 4> Names;
698  M->getMDKindNames(Names);
699
700  if (Names.empty()) return;
701
702  Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
703
704  for (unsigned MDKindID = 0, e = Names.size(); MDKindID != e; ++MDKindID) {
705    Record.push_back(MDKindID);
706    StringRef KName = Names[MDKindID];
707    Record.append(KName.begin(), KName.end());
708
709    Stream.EmitRecord(bitc::METADATA_KIND, Record, 0);
710    Record.clear();
711  }
712
713  Stream.ExitBlock();
714}
715
716static void WriteConstants(unsigned FirstVal, unsigned LastVal,
717                           const llvm_2_9_func::ValueEnumerator &VE,
718                           BitstreamWriter &Stream, bool isGlobal) {
719  if (FirstVal == LastVal) return;
720
721  Stream.EnterSubblock(bitc::CONSTANTS_BLOCK_ID, 4);
722
723  unsigned AggregateAbbrev = 0;
724  unsigned String8Abbrev = 0;
725  unsigned CString7Abbrev = 0;
726  unsigned CString6Abbrev = 0;
727  // If this is a constant pool for the module, emit module-specific abbrevs.
728  if (isGlobal) {
729    // Abbrev for CST_CODE_AGGREGATE.
730    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
731    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_AGGREGATE));
732    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
733    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, Log2_32_Ceil(LastVal+1)));
734    AggregateAbbrev = Stream.EmitAbbrev(Abbv);
735
736    // Abbrev for CST_CODE_STRING.
737    Abbv = new BitCodeAbbrev();
738    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_STRING));
739    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
740    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
741    String8Abbrev = Stream.EmitAbbrev(Abbv);
742    // Abbrev for CST_CODE_CSTRING.
743    Abbv = new BitCodeAbbrev();
744    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
745    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
746    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
747    CString7Abbrev = Stream.EmitAbbrev(Abbv);
748    // Abbrev for CST_CODE_CSTRING.
749    Abbv = new BitCodeAbbrev();
750    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
751    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
752    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
753    CString6Abbrev = Stream.EmitAbbrev(Abbv);
754  }
755
756  SmallVector<uint64_t, 64> Record;
757
758  const llvm_2_9_func::ValueEnumerator::ValueList &Vals = VE.getValues();
759  Type *LastTy = 0;
760  for (unsigned i = FirstVal; i != LastVal; ++i) {
761    const Value *V = Vals[i].first;
762    // If we need to switch types, do so now.
763    if (V->getType() != LastTy) {
764      LastTy = V->getType();
765      Record.push_back(VE.getTypeID(LastTy));
766      Stream.EmitRecord(bitc::CST_CODE_SETTYPE, Record,
767                        CONSTANTS_SETTYPE_ABBREV);
768      Record.clear();
769    }
770
771    if (const InlineAsm *IA = dyn_cast<InlineAsm>(V)) {
772      Record.push_back(unsigned(IA->hasSideEffects()) |
773                       unsigned(IA->isAlignStack()) << 1);
774
775      // Add the asm string.
776      const std::string &AsmStr = IA->getAsmString();
777      Record.push_back(AsmStr.size());
778      for (unsigned i = 0, e = AsmStr.size(); i != e; ++i)
779        Record.push_back(AsmStr[i]);
780
781      // Add the constraint string.
782      const std::string &ConstraintStr = IA->getConstraintString();
783      Record.push_back(ConstraintStr.size());
784      for (unsigned i = 0, e = ConstraintStr.size(); i != e; ++i)
785        Record.push_back(ConstraintStr[i]);
786      Stream.EmitRecord(bitc::CST_CODE_INLINEASM, Record);
787      Record.clear();
788      continue;
789    }
790    const Constant *C = cast<Constant>(V);
791    unsigned Code = -1U;
792    unsigned AbbrevToUse = 0;
793    if (C->isNullValue()) {
794      Code = bitc::CST_CODE_NULL;
795    } else if (isa<UndefValue>(C)) {
796      Code = bitc::CST_CODE_UNDEF;
797    } else if (const ConstantInt *IV = dyn_cast<ConstantInt>(C)) {
798      if (IV->getBitWidth() <= 64) {
799        uint64_t V = IV->getSExtValue();
800        if ((int64_t)V >= 0)
801          Record.push_back(V << 1);
802        else
803          Record.push_back((-V << 1) | 1);
804        Code = bitc::CST_CODE_INTEGER;
805        AbbrevToUse = CONSTANTS_INTEGER_ABBREV;
806      } else {                             // Wide integers, > 64 bits in size.
807        // We have an arbitrary precision integer value to write whose
808        // bit width is > 64. However, in canonical unsigned integer
809        // format it is likely that the high bits are going to be zero.
810        // So, we only write the number of active words.
811        unsigned NWords = IV->getValue().getActiveWords();
812        const uint64_t *RawWords = IV->getValue().getRawData();
813        for (unsigned i = 0; i != NWords; ++i) {
814          int64_t V = RawWords[i];
815          if (V >= 0)
816            Record.push_back(V << 1);
817          else
818            Record.push_back((-V << 1) | 1);
819        }
820        Code = bitc::CST_CODE_WIDE_INTEGER;
821      }
822    } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
823      Code = bitc::CST_CODE_FLOAT;
824      Type *Ty = CFP->getType();
825      if (Ty->isFloatTy() || Ty->isDoubleTy()) {
826        Record.push_back(CFP->getValueAPF().bitcastToAPInt().getZExtValue());
827      } else if (Ty->isX86_FP80Ty()) {
828        // api needed to prevent premature destruction
829        // bits are not in the same order as a normal i80 APInt, compensate.
830        APInt api = CFP->getValueAPF().bitcastToAPInt();
831        const uint64_t *p = api.getRawData();
832        Record.push_back((p[1] << 48) | (p[0] >> 16));
833        Record.push_back(p[0] & 0xffffLL);
834      } else if (Ty->isFP128Ty() || Ty->isPPC_FP128Ty()) {
835        APInt api = CFP->getValueAPF().bitcastToAPInt();
836        const uint64_t *p = api.getRawData();
837        Record.push_back(p[0]);
838        Record.push_back(p[1]);
839      } else {
840        assert (0 && "Unknown FP type!");
841      }
842    } else if (isa<ConstantDataSequential>(C) &&
843               cast<ConstantDataSequential>(C)->isString()) {
844      const ConstantDataSequential *Str = cast<ConstantDataSequential>(C);
845      // Emit constant strings specially.
846      unsigned NumElts = Str->getNumElements();
847      // If this is a null-terminated string, use the denser CSTRING encoding.
848      if (Str->isCString()) {
849        Code = bitc::CST_CODE_CSTRING;
850        --NumElts;  // Don't encode the null, which isn't allowed by char6.
851      } else {
852        Code = bitc::CST_CODE_STRING;
853        AbbrevToUse = String8Abbrev;
854      }
855      bool isCStr7 = Code == bitc::CST_CODE_CSTRING;
856      bool isCStrChar6 = Code == bitc::CST_CODE_CSTRING;
857      for (unsigned i = 0; i != NumElts; ++i) {
858        unsigned char V = Str->getElementAsInteger(i);
859        Record.push_back(V);
860        isCStr7 &= (V & 128) == 0;
861        if (isCStrChar6)
862          isCStrChar6 = BitCodeAbbrevOp::isChar6(V);
863      }
864
865      if (isCStrChar6)
866        AbbrevToUse = CString6Abbrev;
867      else if (isCStr7)
868        AbbrevToUse = CString7Abbrev;
869    } else if (const ConstantDataSequential *CDS =
870                  dyn_cast<ConstantDataSequential>(C)) {
871      Code = bitc::CST_CODE_DATA;
872      Type *EltTy = CDS->getType()->getElementType();
873      if (isa<IntegerType>(EltTy)) {
874        for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i)
875          Record.push_back(CDS->getElementAsInteger(i));
876      } else if (EltTy->isFloatTy()) {
877        for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
878          union { float F; uint32_t I; };
879          F = CDS->getElementAsFloat(i);
880          Record.push_back(I);
881        }
882      } else {
883        assert(EltTy->isDoubleTy() && "Unknown ConstantData element type");
884        for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
885          union { double F; uint64_t I; };
886          F = CDS->getElementAsDouble(i);
887          Record.push_back(I);
888        }
889      }
890    } else if (isa<ConstantArray>(C) || isa<ConstantStruct>(C) ||
891               isa<ConstantVector>(C)) {
892      Code = bitc::CST_CODE_AGGREGATE;
893      for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i)
894        Record.push_back(VE.getValueID(C->getOperand(i)));
895      AbbrevToUse = AggregateAbbrev;
896    } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
897      switch (CE->getOpcode()) {
898      default:
899        if (Instruction::isCast(CE->getOpcode())) {
900          Code = bitc::CST_CODE_CE_CAST;
901          Record.push_back(GetEncodedCastOpcode(CE->getOpcode()));
902          Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
903          Record.push_back(VE.getValueID(C->getOperand(0)));
904          AbbrevToUse = CONSTANTS_CE_CAST_Abbrev;
905        } else {
906          assert(CE->getNumOperands() == 2 && "Unknown constant expr!");
907          Code = bitc::CST_CODE_CE_BINOP;
908          Record.push_back(GetEncodedBinaryOpcode(CE->getOpcode()));
909          Record.push_back(VE.getValueID(C->getOperand(0)));
910          Record.push_back(VE.getValueID(C->getOperand(1)));
911          uint64_t Flags = GetOptimizationFlags(CE);
912          if (Flags != 0)
913            Record.push_back(Flags);
914        }
915        break;
916      case Instruction::GetElementPtr:
917        Code = bitc::CST_CODE_CE_GEP;
918        if (cast<GEPOperator>(C)->isInBounds())
919          Code = bitc::CST_CODE_CE_INBOUNDS_GEP;
920        for (unsigned i = 0, e = CE->getNumOperands(); i != e; ++i) {
921          Record.push_back(VE.getTypeID(C->getOperand(i)->getType()));
922          Record.push_back(VE.getValueID(C->getOperand(i)));
923        }
924        break;
925      case Instruction::Select:
926        Code = bitc::CST_CODE_CE_SELECT;
927        Record.push_back(VE.getValueID(C->getOperand(0)));
928        Record.push_back(VE.getValueID(C->getOperand(1)));
929        Record.push_back(VE.getValueID(C->getOperand(2)));
930        break;
931      case Instruction::ExtractElement:
932        Code = bitc::CST_CODE_CE_EXTRACTELT;
933        Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
934        Record.push_back(VE.getValueID(C->getOperand(0)));
935        Record.push_back(VE.getValueID(C->getOperand(1)));
936        break;
937      case Instruction::InsertElement:
938        Code = bitc::CST_CODE_CE_INSERTELT;
939        Record.push_back(VE.getValueID(C->getOperand(0)));
940        Record.push_back(VE.getValueID(C->getOperand(1)));
941        Record.push_back(VE.getValueID(C->getOperand(2)));
942        break;
943      case Instruction::ShuffleVector:
944        // If the return type and argument types are the same, this is a
945        // standard shufflevector instruction.  If the types are different,
946        // then the shuffle is widening or truncating the input vectors, and
947        // the argument type must also be encoded.
948        if (C->getType() == C->getOperand(0)->getType()) {
949          Code = bitc::CST_CODE_CE_SHUFFLEVEC;
950        } else {
951          Code = bitc::CST_CODE_CE_SHUFVEC_EX;
952          Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
953        }
954        Record.push_back(VE.getValueID(C->getOperand(0)));
955        Record.push_back(VE.getValueID(C->getOperand(1)));
956        Record.push_back(VE.getValueID(C->getOperand(2)));
957        break;
958      case Instruction::ICmp:
959      case Instruction::FCmp:
960        Code = bitc::CST_CODE_CE_CMP;
961        Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
962        Record.push_back(VE.getValueID(C->getOperand(0)));
963        Record.push_back(VE.getValueID(C->getOperand(1)));
964        Record.push_back(CE->getPredicate());
965        break;
966      }
967    } else if (const BlockAddress *BA = dyn_cast<BlockAddress>(C)) {
968      Code = bitc::CST_CODE_BLOCKADDRESS;
969      Record.push_back(VE.getTypeID(BA->getFunction()->getType()));
970      Record.push_back(VE.getValueID(BA->getFunction()));
971      Record.push_back(VE.getGlobalBasicBlockID(BA->getBasicBlock()));
972    } else {
973#ifndef NDEBUG
974      C->dump();
975#endif
976      llvm_unreachable("Unknown constant!");
977    }
978    Stream.EmitRecord(Code, Record, AbbrevToUse);
979    Record.clear();
980  }
981
982  Stream.ExitBlock();
983}
984
985static void WriteModuleConstants(const llvm_2_9_func::ValueEnumerator &VE,
986                                 BitstreamWriter &Stream) {
987  const llvm_2_9_func::ValueEnumerator::ValueList &Vals = VE.getValues();
988
989  // Find the first constant to emit, which is the first non-globalvalue value.
990  // We know globalvalues have been emitted by WriteModuleInfo.
991  for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
992    if (!isa<GlobalValue>(Vals[i].first)) {
993      WriteConstants(i, Vals.size(), VE, Stream, true);
994      return;
995    }
996  }
997}
998
999/// PushValueAndType - The file has to encode both the value and type id for
1000/// many values, because we need to know what type to create for forward
1001/// references.  However, most operands are not forward references, so this type
1002/// field is not needed.
1003///
1004/// This function adds V's value ID to Vals.  If the value ID is higher than the
1005/// instruction ID, then it is a forward reference, and it also includes the
1006/// type ID.
1007static bool PushValueAndType(const Value *V, unsigned InstID,
1008                             SmallVector<unsigned, 64> &Vals,
1009                             llvm_2_9_func::ValueEnumerator &VE) {
1010  unsigned ValID = VE.getValueID(V);
1011  Vals.push_back(ValID);
1012  if (ValID >= InstID) {
1013    Vals.push_back(VE.getTypeID(V->getType()));
1014    return true;
1015  }
1016  return false;
1017}
1018
1019/// WriteInstruction - Emit an instruction to the specified stream.
1020static void WriteInstruction(const Instruction &I, unsigned InstID,
1021                             llvm_2_9_func::ValueEnumerator &VE,
1022                             BitstreamWriter &Stream,
1023                             SmallVector<unsigned, 64> &Vals) {
1024  unsigned Code = 0;
1025  unsigned AbbrevToUse = 0;
1026  VE.setInstructionID(&I);
1027  switch (I.getOpcode()) {
1028  default:
1029    if (Instruction::isCast(I.getOpcode())) {
1030      Code = bitc::FUNC_CODE_INST_CAST;
1031      if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1032        AbbrevToUse = FUNCTION_INST_CAST_ABBREV;
1033      Vals.push_back(VE.getTypeID(I.getType()));
1034      Vals.push_back(GetEncodedCastOpcode(I.getOpcode()));
1035    } else {
1036      assert(isa<BinaryOperator>(I) && "Unknown instruction!");
1037      Code = bitc::FUNC_CODE_INST_BINOP;
1038      if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1039        AbbrevToUse = FUNCTION_INST_BINOP_ABBREV;
1040      Vals.push_back(VE.getValueID(I.getOperand(1)));
1041      Vals.push_back(GetEncodedBinaryOpcode(I.getOpcode()));
1042      uint64_t Flags = GetOptimizationFlags(&I);
1043      if (Flags != 0) {
1044        if (AbbrevToUse == FUNCTION_INST_BINOP_ABBREV)
1045          AbbrevToUse = FUNCTION_INST_BINOP_FLAGS_ABBREV;
1046        Vals.push_back(Flags);
1047      }
1048    }
1049    break;
1050
1051  case Instruction::GetElementPtr:
1052    Code = bitc::FUNC_CODE_INST_GEP;
1053    if (cast<GEPOperator>(&I)->isInBounds())
1054      Code = bitc::FUNC_CODE_INST_INBOUNDS_GEP;
1055    for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1056      PushValueAndType(I.getOperand(i), InstID, Vals, VE);
1057    break;
1058  case Instruction::ExtractValue: {
1059    Code = bitc::FUNC_CODE_INST_EXTRACTVAL;
1060    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1061    const ExtractValueInst *EVI = cast<ExtractValueInst>(&I);
1062    for (const unsigned *i = EVI->idx_begin(), *e = EVI->idx_end(); i != e; ++i)
1063      Vals.push_back(*i);
1064    break;
1065  }
1066  case Instruction::InsertValue: {
1067    Code = bitc::FUNC_CODE_INST_INSERTVAL;
1068    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1069    PushValueAndType(I.getOperand(1), InstID, Vals, VE);
1070    const InsertValueInst *IVI = cast<InsertValueInst>(&I);
1071    for (const unsigned *i = IVI->idx_begin(), *e = IVI->idx_end(); i != e; ++i)
1072      Vals.push_back(*i);
1073    break;
1074  }
1075  case Instruction::Select:
1076    Code = bitc::FUNC_CODE_INST_VSELECT;
1077    PushValueAndType(I.getOperand(1), InstID, Vals, VE);
1078    Vals.push_back(VE.getValueID(I.getOperand(2)));
1079    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1080    break;
1081  case Instruction::ExtractElement:
1082    Code = bitc::FUNC_CODE_INST_EXTRACTELT;
1083    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1084    Vals.push_back(VE.getValueID(I.getOperand(1)));
1085    break;
1086  case Instruction::InsertElement:
1087    Code = bitc::FUNC_CODE_INST_INSERTELT;
1088    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1089    Vals.push_back(VE.getValueID(I.getOperand(1)));
1090    Vals.push_back(VE.getValueID(I.getOperand(2)));
1091    break;
1092  case Instruction::ShuffleVector:
1093    Code = bitc::FUNC_CODE_INST_SHUFFLEVEC;
1094    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1095    Vals.push_back(VE.getValueID(I.getOperand(1)));
1096    Vals.push_back(VE.getValueID(I.getOperand(2)));
1097    break;
1098  case Instruction::ICmp:
1099  case Instruction::FCmp:
1100    // compare returning Int1Ty or vector of Int1Ty
1101    Code = bitc::FUNC_CODE_INST_CMP2;
1102    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1103    Vals.push_back(VE.getValueID(I.getOperand(1)));
1104    Vals.push_back(cast<CmpInst>(I).getPredicate());
1105    break;
1106
1107  case Instruction::Ret:
1108    {
1109      Code = bitc::FUNC_CODE_INST_RET;
1110      unsigned NumOperands = I.getNumOperands();
1111      if (NumOperands == 0)
1112        AbbrevToUse = FUNCTION_INST_RET_VOID_ABBREV;
1113      else if (NumOperands == 1) {
1114        if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1115          AbbrevToUse = FUNCTION_INST_RET_VAL_ABBREV;
1116      } else {
1117        for (unsigned i = 0, e = NumOperands; i != e; ++i)
1118          PushValueAndType(I.getOperand(i), InstID, Vals, VE);
1119      }
1120    }
1121    break;
1122  case Instruction::Br:
1123    {
1124      Code = bitc::FUNC_CODE_INST_BR;
1125      BranchInst &II = cast<BranchInst>(I);
1126      Vals.push_back(VE.getValueID(II.getSuccessor(0)));
1127      if (II.isConditional()) {
1128        Vals.push_back(VE.getValueID(II.getSuccessor(1)));
1129        Vals.push_back(VE.getValueID(II.getCondition()));
1130      }
1131    }
1132    break;
1133  case Instruction::Switch:
1134    Code = bitc::FUNC_CODE_INST_SWITCH;
1135    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1136    for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1137      Vals.push_back(VE.getValueID(I.getOperand(i)));
1138    break;
1139  case Instruction::IndirectBr:
1140    Code = bitc::FUNC_CODE_INST_INDIRECTBR;
1141    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1142    for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1143      Vals.push_back(VE.getValueID(I.getOperand(i)));
1144    break;
1145
1146  case Instruction::Invoke: {
1147    const InvokeInst *II = cast<InvokeInst>(&I);
1148    const Value *Callee(II->getCalledValue());
1149    PointerType *PTy = cast<PointerType>(Callee->getType());
1150    FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1151    Code = bitc::FUNC_CODE_INST_INVOKE;
1152
1153    Vals.push_back(VE.getAttributeID(II->getAttributes()));
1154    Vals.push_back(II->getCallingConv());
1155    Vals.push_back(VE.getValueID(II->getNormalDest()));
1156    Vals.push_back(VE.getValueID(II->getUnwindDest()));
1157    PushValueAndType(Callee, InstID, Vals, VE);
1158
1159    // Emit value #'s for the fixed parameters.
1160    for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
1161      Vals.push_back(VE.getValueID(I.getOperand(i)));  // fixed param.
1162
1163    // Emit type/value pairs for varargs params.
1164    if (FTy->isVarArg()) {
1165      for (unsigned i = FTy->getNumParams(), e = I.getNumOperands()-3;
1166           i != e; ++i)
1167        PushValueAndType(I.getOperand(i), InstID, Vals, VE); // vararg
1168    }
1169    break;
1170  }
1171  case Instruction::Resume:
1172    Code = bitc::FUNC_CODE_INST_RESUME;
1173    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1174    break;
1175  case Instruction::Unreachable:
1176    Code = bitc::FUNC_CODE_INST_UNREACHABLE;
1177    AbbrevToUse = FUNCTION_INST_UNREACHABLE_ABBREV;
1178    break;
1179
1180  case Instruction::PHI: {
1181    const PHINode &PN = cast<PHINode>(I);
1182    Code = bitc::FUNC_CODE_INST_PHI;
1183    Vals.push_back(VE.getTypeID(PN.getType()));
1184    for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
1185      Vals.push_back(VE.getValueID(PN.getIncomingValue(i)));
1186      Vals.push_back(VE.getValueID(PN.getIncomingBlock(i)));
1187    }
1188    break;
1189  }
1190
1191  case Instruction::LandingPad: {
1192    const LandingPadInst &LP = cast<LandingPadInst>(I);
1193    Code = bitc::FUNC_CODE_INST_LANDINGPAD;
1194    Vals.push_back(VE.getTypeID(LP.getType()));
1195    PushValueAndType(LP.getPersonalityFn(), InstID, Vals, VE);
1196    Vals.push_back(LP.isCleanup());
1197    Vals.push_back(LP.getNumClauses());
1198    for (unsigned I = 0, E = LP.getNumClauses(); I != E; ++I) {
1199      if (LP.isCatch(I))
1200        Vals.push_back(LandingPadInst::Catch);
1201      else
1202        Vals.push_back(LandingPadInst::Filter);
1203      PushValueAndType(LP.getClause(I), InstID, Vals, VE);
1204    }
1205    break;
1206  }
1207
1208  case Instruction::Alloca:
1209    Code = bitc::FUNC_CODE_INST_ALLOCA;
1210    Vals.push_back(VE.getTypeID(I.getType()));
1211    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1212    Vals.push_back(VE.getValueID(I.getOperand(0))); // size.
1213    Vals.push_back(Log2_32(cast<AllocaInst>(I).getAlignment())+1);
1214    break;
1215
1216  case Instruction::Load:
1217    if (cast<LoadInst>(I).isAtomic()) {
1218      Code = bitc::FUNC_CODE_INST_LOADATOMIC;
1219      PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1220    } else {
1221      Code = bitc::FUNC_CODE_INST_LOAD;
1222      if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))  // ptr
1223        AbbrevToUse = FUNCTION_INST_LOAD_ABBREV;
1224    }
1225    Vals.push_back(Log2_32(cast<LoadInst>(I).getAlignment())+1);
1226    Vals.push_back(cast<LoadInst>(I).isVolatile());
1227    if (cast<LoadInst>(I).isAtomic()) {
1228      Vals.push_back(GetEncodedOrdering(cast<LoadInst>(I).getOrdering()));
1229      Vals.push_back(GetEncodedSynchScope(cast<LoadInst>(I).getSynchScope()));
1230    }
1231    break;
1232  case Instruction::Store:
1233    if (cast<StoreInst>(I).isAtomic())
1234      Code = bitc::FUNC_CODE_INST_STOREATOMIC;
1235    else
1236      Code = bitc::FUNC_CODE_INST_STORE;
1237    PushValueAndType(I.getOperand(1), InstID, Vals, VE);  // ptrty + ptr
1238    Vals.push_back(VE.getValueID(I.getOperand(0)));       // val.
1239    Vals.push_back(Log2_32(cast<StoreInst>(I).getAlignment())+1);
1240    Vals.push_back(cast<StoreInst>(I).isVolatile());
1241    if (cast<StoreInst>(I).isAtomic()) {
1242      Vals.push_back(GetEncodedOrdering(cast<StoreInst>(I).getOrdering()));
1243      Vals.push_back(GetEncodedSynchScope(cast<StoreInst>(I).getSynchScope()));
1244    }
1245    break;
1246  case Instruction::AtomicCmpXchg:
1247    Code = bitc::FUNC_CODE_INST_CMPXCHG;
1248    PushValueAndType(I.getOperand(0), InstID, Vals, VE);  // ptrty + ptr
1249    Vals.push_back(VE.getValueID(I.getOperand(1)));       // cmp.
1250    Vals.push_back(VE.getValueID(I.getOperand(2)));       // newval.
1251    Vals.push_back(cast<AtomicCmpXchgInst>(I).isVolatile());
1252    Vals.push_back(GetEncodedOrdering(
1253                     cast<AtomicCmpXchgInst>(I).getOrdering()));
1254    Vals.push_back(GetEncodedSynchScope(
1255                     cast<AtomicCmpXchgInst>(I).getSynchScope()));
1256    break;
1257  case Instruction::AtomicRMW:
1258    Code = bitc::FUNC_CODE_INST_ATOMICRMW;
1259    PushValueAndType(I.getOperand(0), InstID, Vals, VE);  // ptrty + ptr
1260    Vals.push_back(VE.getValueID(I.getOperand(1)));       // val.
1261    Vals.push_back(GetEncodedRMWOperation(
1262                     cast<AtomicRMWInst>(I).getOperation()));
1263    Vals.push_back(cast<AtomicRMWInst>(I).isVolatile());
1264    Vals.push_back(GetEncodedOrdering(cast<AtomicRMWInst>(I).getOrdering()));
1265    Vals.push_back(GetEncodedSynchScope(
1266                     cast<AtomicRMWInst>(I).getSynchScope()));
1267    break;
1268  case Instruction::Fence:
1269    Code = bitc::FUNC_CODE_INST_FENCE;
1270    Vals.push_back(GetEncodedOrdering(cast<FenceInst>(I).getOrdering()));
1271    Vals.push_back(GetEncodedSynchScope(cast<FenceInst>(I).getSynchScope()));
1272    break;
1273  case Instruction::Call: {
1274    const CallInst &CI = cast<CallInst>(I);
1275    PointerType *PTy = cast<PointerType>(CI.getCalledValue()->getType());
1276    FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1277
1278    Code = bitc::FUNC_CODE_INST_CALL;
1279
1280    Vals.push_back(VE.getAttributeID(CI.getAttributes()));
1281    Vals.push_back((CI.getCallingConv() << 1) | unsigned(CI.isTailCall()));
1282    PushValueAndType(CI.getCalledValue(), InstID, Vals, VE);  // Callee
1283
1284    // Emit value #'s for the fixed parameters.
1285    for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
1286      Vals.push_back(VE.getValueID(CI.getArgOperand(i)));  // fixed param.
1287
1288    // Emit type/value pairs for varargs params.
1289    if (FTy->isVarArg()) {
1290      for (unsigned i = FTy->getNumParams(), e = CI.getNumArgOperands();
1291           i != e; ++i)
1292        PushValueAndType(CI.getArgOperand(i), InstID, Vals, VE);  // varargs
1293    }
1294    break;
1295  }
1296  case Instruction::VAArg:
1297    Code = bitc::FUNC_CODE_INST_VAARG;
1298    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));   // valistty
1299    Vals.push_back(VE.getValueID(I.getOperand(0))); // valist.
1300    Vals.push_back(VE.getTypeID(I.getType())); // restype.
1301    break;
1302  }
1303
1304  Stream.EmitRecord(Code, Vals, AbbrevToUse);
1305  Vals.clear();
1306}
1307
1308// Emit names for globals/functions etc.
1309static void WriteValueSymbolTable(const ValueSymbolTable &VST,
1310                                  const llvm_2_9_func::ValueEnumerator &VE,
1311                                  BitstreamWriter &Stream) {
1312  if (VST.empty()) return;
1313  Stream.EnterSubblock(bitc::VALUE_SYMTAB_BLOCK_ID, 4);
1314
1315  // FIXME: Set up the abbrev, we know how many values there are!
1316  // FIXME: We know if the type names can use 7-bit ascii.
1317  SmallVector<unsigned, 64> NameVals;
1318
1319  for (ValueSymbolTable::const_iterator SI = VST.begin(), SE = VST.end();
1320       SI != SE; ++SI) {
1321
1322    const ValueName &Name = *SI;
1323
1324    // Figure out the encoding to use for the name.
1325    bool is7Bit = true;
1326    bool isChar6 = true;
1327    for (const char *C = Name.getKeyData(), *E = C+Name.getKeyLength();
1328         C != E; ++C) {
1329      if (isChar6)
1330        isChar6 = BitCodeAbbrevOp::isChar6(*C);
1331      if ((unsigned char)*C & 128) {
1332        is7Bit = false;
1333        break;  // don't bother scanning the rest.
1334      }
1335    }
1336
1337    unsigned AbbrevToUse = VST_ENTRY_8_ABBREV;
1338
1339    // VST_ENTRY:   [valueid, namechar x N]
1340    // VST_BBENTRY: [bbid, namechar x N]
1341    unsigned Code;
1342    if (isa<BasicBlock>(SI->getValue())) {
1343      Code = bitc::VST_CODE_BBENTRY;
1344      if (isChar6)
1345        AbbrevToUse = VST_BBENTRY_6_ABBREV;
1346    } else {
1347      Code = bitc::VST_CODE_ENTRY;
1348      if (isChar6)
1349        AbbrevToUse = VST_ENTRY_6_ABBREV;
1350      else if (is7Bit)
1351        AbbrevToUse = VST_ENTRY_7_ABBREV;
1352    }
1353
1354    NameVals.push_back(VE.getValueID(SI->getValue()));
1355    for (const char *P = Name.getKeyData(),
1356         *E = Name.getKeyData()+Name.getKeyLength(); P != E; ++P)
1357      NameVals.push_back((unsigned char)*P);
1358
1359    // Emit the finished record.
1360    Stream.EmitRecord(Code, NameVals, AbbrevToUse);
1361    NameVals.clear();
1362  }
1363  Stream.ExitBlock();
1364}
1365
1366/// WriteFunction - Emit a function body to the module stream.
1367static void WriteFunction(const Function &F, llvm_2_9_func::ValueEnumerator &VE,
1368                          BitstreamWriter &Stream) {
1369  Stream.EnterSubblock(bitc::FUNCTION_BLOCK_ID, 4);
1370  VE.incorporateFunction(F);
1371
1372  SmallVector<unsigned, 64> Vals;
1373
1374  // Emit the number of basic blocks, so the reader can create them ahead of
1375  // time.
1376  Vals.push_back(VE.getBasicBlocks().size());
1377  Stream.EmitRecord(bitc::FUNC_CODE_DECLAREBLOCKS, Vals);
1378  Vals.clear();
1379
1380  // If there are function-local constants, emit them now.
1381  unsigned CstStart, CstEnd;
1382  VE.getFunctionConstantRange(CstStart, CstEnd);
1383  WriteConstants(CstStart, CstEnd, VE, Stream, false);
1384
1385  // If there is function-local metadata, emit it now.
1386  WriteFunctionLocalMetadata(F, VE, Stream);
1387
1388  // Keep a running idea of what the instruction ID is.
1389  unsigned InstID = CstEnd;
1390
1391  bool NeedsMetadataAttachment = false;
1392
1393  DebugLoc LastDL;
1394
1395  // Finally, emit all the instructions, in order.
1396  for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
1397    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
1398         I != E; ++I) {
1399      WriteInstruction(*I, InstID, VE, Stream, Vals);
1400
1401      if (!I->getType()->isVoidTy())
1402        ++InstID;
1403
1404      // If the instruction has metadata, write a metadata attachment later.
1405      NeedsMetadataAttachment |= I->hasMetadataOtherThanDebugLoc();
1406
1407      // If the instruction has a debug location, emit it.
1408      DebugLoc DL = I->getDebugLoc();
1409      if (DL.isUnknown()) {
1410        // nothing todo.
1411      } else if (DL == LastDL) {
1412        // Just repeat the same debug loc as last time.
1413        Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC_AGAIN, Vals);
1414      } else {
1415        MDNode *Scope, *IA;
1416        DL.getScopeAndInlinedAt(Scope, IA, I->getContext());
1417
1418        Vals.push_back(DL.getLine());
1419        Vals.push_back(DL.getCol());
1420        Vals.push_back(Scope ? VE.getValueID(Scope)+1 : 0);
1421        Vals.push_back(IA ? VE.getValueID(IA)+1 : 0);
1422        Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC, Vals);
1423        Vals.clear();
1424
1425        LastDL = DL;
1426      }
1427    }
1428
1429  // Emit names for all the instructions etc.
1430  WriteValueSymbolTable(F.getValueSymbolTable(), VE, Stream);
1431
1432  if (NeedsMetadataAttachment)
1433    WriteMetadataAttachment(F, VE, Stream);
1434  VE.purgeFunction();
1435  Stream.ExitBlock();
1436}
1437
1438// Emit blockinfo, which defines the standard abbreviations etc.
1439static void WriteBlockInfo(const llvm_2_9_func::ValueEnumerator &VE,
1440                           BitstreamWriter &Stream) {
1441  // We only want to emit block info records for blocks that have multiple
1442  // instances: CONSTANTS_BLOCK, FUNCTION_BLOCK and VALUE_SYMTAB_BLOCK.  Other
1443  // blocks can defined their abbrevs inline.
1444  Stream.EnterBlockInfoBlock(2);
1445
1446  { // 8-bit fixed-width VST_ENTRY/VST_BBENTRY strings.
1447    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1448    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3));
1449    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1450    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1451    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
1452    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1453                                   Abbv) != VST_ENTRY_8_ABBREV)
1454      llvm_unreachable("Unexpected abbrev ordering!");
1455  }
1456
1457  { // 7-bit fixed width VST_ENTRY strings.
1458    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1459    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1460    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1461    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1462    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
1463    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1464                                   Abbv) != VST_ENTRY_7_ABBREV)
1465      llvm_unreachable("Unexpected abbrev ordering!");
1466  }
1467  { // 6-bit char6 VST_ENTRY strings.
1468    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1469    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1470    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1471    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1472    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1473    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1474                                   Abbv) != VST_ENTRY_6_ABBREV)
1475      llvm_unreachable("Unexpected abbrev ordering!");
1476  }
1477  { // 6-bit char6 VST_BBENTRY strings.
1478    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1479    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_BBENTRY));
1480    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1481    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1482    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1483    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1484                                   Abbv) != VST_BBENTRY_6_ABBREV)
1485      llvm_unreachable("Unexpected abbrev ordering!");
1486  }
1487
1488
1489
1490  { // SETTYPE abbrev for CONSTANTS_BLOCK.
1491    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1492    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_SETTYPE));
1493    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1494                              Log2_32_Ceil(VE.getTypes().size()+1)));
1495    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1496                                   Abbv) != CONSTANTS_SETTYPE_ABBREV)
1497      llvm_unreachable("Unexpected abbrev ordering!");
1498  }
1499
1500  { // INTEGER abbrev for CONSTANTS_BLOCK.
1501    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1502    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_INTEGER));
1503    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1504    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1505                                   Abbv) != CONSTANTS_INTEGER_ABBREV)
1506      llvm_unreachable("Unexpected abbrev ordering!");
1507  }
1508
1509  { // CE_CAST abbrev for CONSTANTS_BLOCK.
1510    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1511    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CE_CAST));
1512    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // cast opc
1513    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // typeid
1514                              Log2_32_Ceil(VE.getTypes().size()+1)));
1515    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));    // value id
1516
1517    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1518                                   Abbv) != CONSTANTS_CE_CAST_Abbrev)
1519      llvm_unreachable("Unexpected abbrev ordering!");
1520  }
1521  { // NULL abbrev for CONSTANTS_BLOCK.
1522    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1523    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_NULL));
1524    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1525                                   Abbv) != CONSTANTS_NULL_Abbrev)
1526      llvm_unreachable("Unexpected abbrev ordering!");
1527  }
1528
1529  // FIXME: This should only use space for first class types!
1530
1531  { // INST_LOAD abbrev for FUNCTION_BLOCK.
1532    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1533    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_LOAD));
1534    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Ptr
1535    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4)); // Align
1536    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // volatile
1537    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1538                                   Abbv) != FUNCTION_INST_LOAD_ABBREV)
1539      llvm_unreachable("Unexpected abbrev ordering!");
1540  }
1541  { // INST_BINOP abbrev for FUNCTION_BLOCK.
1542    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1543    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1544    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1545    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1546    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1547    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1548                                   Abbv) != FUNCTION_INST_BINOP_ABBREV)
1549      llvm_unreachable("Unexpected abbrev ordering!");
1550  }
1551  { // INST_BINOP_FLAGS abbrev for FUNCTION_BLOCK.
1552    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1553    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1554    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1555    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1556    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1557    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7)); // flags
1558    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1559                                   Abbv) != FUNCTION_INST_BINOP_FLAGS_ABBREV)
1560      llvm_unreachable("Unexpected abbrev ordering!");
1561  }
1562  { // INST_CAST abbrev for FUNCTION_BLOCK.
1563    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1564    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_CAST));
1565    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));    // OpVal
1566    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // dest ty
1567                              Log2_32_Ceil(VE.getTypes().size()+1)));
1568    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // opc
1569    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1570                                   Abbv) != FUNCTION_INST_CAST_ABBREV)
1571      llvm_unreachable("Unexpected abbrev ordering!");
1572  }
1573
1574  { // INST_RET abbrev for FUNCTION_BLOCK.
1575    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1576    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1577    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1578                                   Abbv) != FUNCTION_INST_RET_VOID_ABBREV)
1579      llvm_unreachable("Unexpected abbrev ordering!");
1580  }
1581  { // INST_RET abbrev for FUNCTION_BLOCK.
1582    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1583    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1584    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ValID
1585    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1586                                   Abbv) != FUNCTION_INST_RET_VAL_ABBREV)
1587      llvm_unreachable("Unexpected abbrev ordering!");
1588  }
1589  { // INST_UNREACHABLE abbrev for FUNCTION_BLOCK.
1590    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1591    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_UNREACHABLE));
1592    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1593                                   Abbv) != FUNCTION_INST_UNREACHABLE_ABBREV)
1594      llvm_unreachable("Unexpected abbrev ordering!");
1595  }
1596
1597  Stream.ExitBlock();
1598}
1599
1600
1601/// WriteModule - Emit the specified module to the bitstream.
1602static void WriteModule(const Module *M, BitstreamWriter &Stream) {
1603  Stream.EnterSubblock(bitc::MODULE_BLOCK_ID, 3);
1604
1605  // Emit the version number if it is non-zero.
1606  if (CurVersion) {
1607    SmallVector<unsigned, 1> Vals;
1608    Vals.push_back(CurVersion);
1609    Stream.EmitRecord(bitc::MODULE_CODE_VERSION, Vals);
1610  }
1611
1612  // Analyze the module, enumerating globals, functions, etc.
1613  llvm_2_9_func::ValueEnumerator VE(M);
1614
1615  // Emit blockinfo, which defines the standard abbreviations etc.
1616  WriteBlockInfo(VE, Stream);
1617
1618  // Emit information about parameter attributes.
1619  WriteAttributeTable(VE, Stream);
1620
1621  // Emit information describing all of the types in the module.
1622  WriteTypeTable(VE, Stream);
1623
1624  // Emit top-level description of module, including target triple, inline asm,
1625  // descriptors for global variables, and function prototype info.
1626  WriteModuleInfo(M, VE, Stream);
1627
1628  // Emit constants.
1629  WriteModuleConstants(VE, Stream);
1630
1631  // Emit metadata.
1632  WriteModuleMetadata(M, VE, Stream);
1633
1634  // Emit function bodies.
1635  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F)
1636    if (!F->isDeclaration())
1637      WriteFunction(*F, VE, Stream);
1638
1639  // Emit metadata.
1640  WriteModuleMetadataStore(M, Stream);
1641
1642  // Emit names for globals/functions etc.
1643  WriteValueSymbolTable(M->getValueSymbolTable(), VE, Stream);
1644
1645  Stream.ExitBlock();
1646}
1647
1648/// EmitDarwinBCHeader - If generating a bc file on darwin, we have to emit a
1649/// header and trailer to make it compatible with the system archiver.  To do
1650/// this we emit the following header, and then emit a trailer that pads the
1651/// file out to be a multiple of 16 bytes.
1652///
1653/// struct bc_header {
1654///   uint32_t Magic;         // 0x0B17C0DE
1655///   uint32_t Version;       // Version, currently always 0.
1656///   uint32_t BitcodeOffset; // Offset to traditional bitcode file.
1657///   uint32_t BitcodeSize;   // Size of traditional bitcode file.
1658///   uint32_t CPUType;       // CPU specifier.
1659///   ... potentially more later ...
1660/// };
1661enum {
1662  DarwinBCSizeFieldOffset = 3*4, // Offset to bitcode_size.
1663  DarwinBCHeaderSize = 5*4
1664};
1665
1666static void WriteInt32ToBuffer(uint32_t Value, SmallVectorImpl<char> &Buffer,
1667                               uint32_t &Position) {
1668  Buffer[Position + 0] = (unsigned char) (Value >>  0);
1669  Buffer[Position + 1] = (unsigned char) (Value >>  8);
1670  Buffer[Position + 2] = (unsigned char) (Value >> 16);
1671  Buffer[Position + 3] = (unsigned char) (Value >> 24);
1672  Position += 4;
1673}
1674
1675static void EmitDarwinBCHeaderAndTrailer(SmallVectorImpl<char> &Buffer,
1676                                         const Triple &TT) {
1677  unsigned CPUType = ~0U;
1678
1679  // Match x86_64-*, i[3-9]86-*, powerpc-*, powerpc64-*, arm-*, thumb-*,
1680  // armv[0-9]-*, thumbv[0-9]-*, armv5te-*, or armv6t2-*. The CPUType is a magic
1681  // number from /usr/include/mach/machine.h.  It is ok to reproduce the
1682  // specific constants here because they are implicitly part of the Darwin ABI.
1683  enum {
1684    DARWIN_CPU_ARCH_ABI64      = 0x01000000,
1685    DARWIN_CPU_TYPE_X86        = 7,
1686    DARWIN_CPU_TYPE_ARM        = 12,
1687    DARWIN_CPU_TYPE_POWERPC    = 18
1688  };
1689
1690  Triple::ArchType Arch = TT.getArch();
1691  if (Arch == Triple::x86_64)
1692    CPUType = DARWIN_CPU_TYPE_X86 | DARWIN_CPU_ARCH_ABI64;
1693  else if (Arch == Triple::x86)
1694    CPUType = DARWIN_CPU_TYPE_X86;
1695  else if (Arch == Triple::ppc)
1696    CPUType = DARWIN_CPU_TYPE_POWERPC;
1697  else if (Arch == Triple::ppc64)
1698    CPUType = DARWIN_CPU_TYPE_POWERPC | DARWIN_CPU_ARCH_ABI64;
1699  else if (Arch == Triple::arm || Arch == Triple::thumb)
1700    CPUType = DARWIN_CPU_TYPE_ARM;
1701
1702  // Traditional Bitcode starts after header.
1703  assert(Buffer.size() >= DarwinBCHeaderSize &&
1704         "Expected header size to be reserved");
1705  unsigned BCOffset = DarwinBCHeaderSize;
1706  unsigned BCSize = Buffer.size()-DarwinBCHeaderSize;
1707
1708  // Write the magic and version.
1709  unsigned Position = 0;
1710  WriteInt32ToBuffer(0x0B17C0DE , Buffer, Position);
1711  WriteInt32ToBuffer(0          , Buffer, Position); // Version.
1712  WriteInt32ToBuffer(BCOffset   , Buffer, Position);
1713  WriteInt32ToBuffer(BCSize     , Buffer, Position);
1714  WriteInt32ToBuffer(CPUType    , Buffer, Position);
1715
1716  // If the file is not a multiple of 16 bytes, insert dummy padding.
1717  while (Buffer.size() & 15)
1718    Buffer.push_back(0);
1719}
1720
1721/// WriteBitcodeToFile - Write the specified module to the specified output
1722/// stream.
1723void llvm_2_9_func::WriteBitcodeToFile(const Module *M, raw_ostream &Out) {
1724  SmallVector<char, 1024> Buffer;
1725  Buffer.reserve(256*1024);
1726
1727  // If this is darwin or another generic macho target, reserve space for the
1728  // header.
1729  Triple TT(M->getTargetTriple());
1730  if (TT.isOSDarwin())
1731    Buffer.insert(Buffer.begin(), DarwinBCHeaderSize, 0);
1732
1733  // Emit the module into the buffer.
1734  {
1735    BitstreamWriter Stream(Buffer);
1736
1737    // Emit the file header.
1738    Stream.Emit((unsigned)'B', 8);
1739    Stream.Emit((unsigned)'C', 8);
1740    Stream.Emit(0x0, 4);
1741    Stream.Emit(0xC, 4);
1742    Stream.Emit(0xE, 4);
1743    Stream.Emit(0xD, 4);
1744
1745    // Emit the module.
1746    WriteModule(M, Stream);
1747  }
1748
1749  if (TT.isOSDarwin())
1750    EmitDarwinBCHeaderAndTrailer(Buffer, TT);
1751
1752  // Write the generated bitstream to "Out".
1753  Out.write((char*)&Buffer.front(), Buffer.size());
1754}
1755