BitcodeWriter.cpp revision c706907a8041faaa882f9bd87f1d1c1669023a62 
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_3_2.h"
15#include "legacy_bitcode.h"
16#include "ValueEnumerator.h"
17#include "llvm/ADT/Triple.h"
18#include "llvm/Bitcode/BitstreamWriter.h"
19#include "llvm/Bitcode/LLVMBitCodes.h"
20#include "llvm/IR/Constants.h"
21#include "llvm/IR/DebugInfoMetadata.h"
22#include "llvm/IR/DerivedTypes.h"
23#include "llvm/IR/InlineAsm.h"
24#include "llvm/IR/Instructions.h"
25#include "llvm/IR/Module.h"
26#include "llvm/IR/Operator.h"
27#include "llvm/IR/UseListOrder.h"
28#include "llvm/IR/ValueSymbolTable.h"
29#include "llvm/Support/CommandLine.h"
30#include "llvm/Support/ErrorHandling.h"
31#include "llvm/Support/MathExtras.h"
32#include "llvm/Support/Program.h"
33#include "llvm/Support/raw_ostream.h"
34#include <cctype>
35#include <map>
36using namespace llvm;
37
38/// These are manifest constants used by the bitcode writer. They do not need to
39/// be kept in sync with the reader, but need to be consistent within this file.
40enum {
41  // VALUE_SYMTAB_BLOCK abbrev id's.
42  VST_ENTRY_8_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
43  VST_ENTRY_7_ABBREV,
44  VST_ENTRY_6_ABBREV,
45  VST_BBENTRY_6_ABBREV,
46
47  // CONSTANTS_BLOCK abbrev id's.
48  CONSTANTS_SETTYPE_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
49  CONSTANTS_INTEGER_ABBREV,
50  CONSTANTS_CE_CAST_Abbrev,
51  CONSTANTS_NULL_Abbrev,
52
53  // FUNCTION_BLOCK abbrev id's.
54  FUNCTION_INST_LOAD_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
55  FUNCTION_INST_BINOP_ABBREV,
56  FUNCTION_INST_BINOP_FLAGS_ABBREV,
57  FUNCTION_INST_CAST_ABBREV,
58  FUNCTION_INST_RET_VOID_ABBREV,
59  FUNCTION_INST_RET_VAL_ABBREV,
60  FUNCTION_INST_UNREACHABLE_ABBREV
61};
62
63static unsigned GetEncodedCastOpcode(unsigned Opcode) {
64  switch (Opcode) {
65  default: llvm_unreachable("Unknown cast instruction!");
66  case Instruction::Trunc   : return bitc::CAST_TRUNC;
67  case Instruction::ZExt    : return bitc::CAST_ZEXT;
68  case Instruction::SExt    : return bitc::CAST_SEXT;
69  case Instruction::FPToUI  : return bitc::CAST_FPTOUI;
70  case Instruction::FPToSI  : return bitc::CAST_FPTOSI;
71  case Instruction::UIToFP  : return bitc::CAST_UITOFP;
72  case Instruction::SIToFP  : return bitc::CAST_SITOFP;
73  case Instruction::FPTrunc : return bitc::CAST_FPTRUNC;
74  case Instruction::FPExt   : return bitc::CAST_FPEXT;
75  case Instruction::PtrToInt: return bitc::CAST_PTRTOINT;
76  case Instruction::IntToPtr: return bitc::CAST_INTTOPTR;
77  case Instruction::BitCast : return bitc::CAST_BITCAST;
78  }
79}
80
81static unsigned GetEncodedBinaryOpcode(unsigned Opcode) {
82  switch (Opcode) {
83  default: llvm_unreachable("Unknown binary instruction!");
84  case Instruction::Add:
85  case Instruction::FAdd: return bitc::BINOP_ADD;
86  case Instruction::Sub:
87  case Instruction::FSub: return bitc::BINOP_SUB;
88  case Instruction::Mul:
89  case Instruction::FMul: return bitc::BINOP_MUL;
90  case Instruction::UDiv: return bitc::BINOP_UDIV;
91  case Instruction::FDiv:
92  case Instruction::SDiv: return bitc::BINOP_SDIV;
93  case Instruction::URem: return bitc::BINOP_UREM;
94  case Instruction::FRem:
95  case Instruction::SRem: return bitc::BINOP_SREM;
96  case Instruction::Shl:  return bitc::BINOP_SHL;
97  case Instruction::LShr: return bitc::BINOP_LSHR;
98  case Instruction::AShr: return bitc::BINOP_ASHR;
99  case Instruction::And:  return bitc::BINOP_AND;
100  case Instruction::Or:   return bitc::BINOP_OR;
101  case Instruction::Xor:  return bitc::BINOP_XOR;
102  }
103}
104
105static unsigned GetEncodedRMWOperation(AtomicRMWInst::BinOp Op) {
106  switch (Op) {
107  default: llvm_unreachable("Unknown RMW operation!");
108  case AtomicRMWInst::Xchg: return bitc::RMW_XCHG;
109  case AtomicRMWInst::Add: return bitc::RMW_ADD;
110  case AtomicRMWInst::Sub: return bitc::RMW_SUB;
111  case AtomicRMWInst::And: return bitc::RMW_AND;
112  case AtomicRMWInst::Nand: return bitc::RMW_NAND;
113  case AtomicRMWInst::Or: return bitc::RMW_OR;
114  case AtomicRMWInst::Xor: return bitc::RMW_XOR;
115  case AtomicRMWInst::Max: return bitc::RMW_MAX;
116  case AtomicRMWInst::Min: return bitc::RMW_MIN;
117  case AtomicRMWInst::UMax: return bitc::RMW_UMAX;
118  case AtomicRMWInst::UMin: return bitc::RMW_UMIN;
119  }
120}
121
122static unsigned GetEncodedOrdering(AtomicOrdering Ordering) {
123  switch (Ordering) {
124  case NotAtomic: return bitc::ORDERING_NOTATOMIC;
125  case Unordered: return bitc::ORDERING_UNORDERED;
126  case Monotonic: return bitc::ORDERING_MONOTONIC;
127  case Acquire: return bitc::ORDERING_ACQUIRE;
128  case Release: return bitc::ORDERING_RELEASE;
129  case AcquireRelease: return bitc::ORDERING_ACQREL;
130  case SequentiallyConsistent: return bitc::ORDERING_SEQCST;
131  }
132  llvm_unreachable("Invalid ordering");
133}
134
135static unsigned GetEncodedSynchScope(SynchronizationScope SynchScope) {
136  switch (SynchScope) {
137  case SingleThread: return bitc::SYNCHSCOPE_SINGLETHREAD;
138  case CrossThread: return bitc::SYNCHSCOPE_CROSSTHREAD;
139  }
140  llvm_unreachable("Invalid synch scope");
141}
142
143static void WriteStringRecord(unsigned Code, StringRef Str,
144                              unsigned AbbrevToUse, BitstreamWriter &Stream) {
145  SmallVector<unsigned, 64> Vals;
146
147  // Code: [strchar x N]
148  for (unsigned i = 0, e = Str.size(); i != e; ++i) {
149    if (AbbrevToUse && !BitCodeAbbrevOp::isChar6(Str[i]))
150      AbbrevToUse = 0;
151    Vals.push_back(Str[i]);
152  }
153
154  // Emit the finished record.
155  Stream.EmitRecord(Code, Vals, AbbrevToUse);
156}
157
158// Emit information about parameter attributes.
159static void WriteAttributeTable(const llvm_3_2::ValueEnumerator &VE,
160                                BitstreamWriter &Stream) {
161  const std::vector<AttributeSet> &Attrs = VE.getAttributes();
162  if (Attrs.empty()) return;
163
164  Stream.EnterSubblock(bitc::PARAMATTR_BLOCK_ID, 3);
165
166  SmallVector<uint64_t, 64> Record;
167  for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
168    const AttributeSet &A = Attrs[i];
169    for (unsigned i = 0, e = A.getNumSlots(); i != e; ++i) {
170      Record.push_back(A.getSlotIndex(i));
171      Record.push_back(encodeLLVMAttributesForBitcode(A, A.getSlotIndex(i)));
172    }
173
174    // This needs to use the 3.2 entry type
175    Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY_OLD, Record);
176    Record.clear();
177  }
178
179  Stream.ExitBlock();
180}
181
182/// WriteTypeTable - Write out the type table for a module.
183static void WriteTypeTable(const llvm_3_2::ValueEnumerator &VE,
184                           BitstreamWriter &Stream) {
185  const llvm_3_2::ValueEnumerator::TypeList &TypeList = VE.getTypes();
186
187  Stream.EnterSubblock(bitc::TYPE_BLOCK_ID_NEW, 4 /*count from # abbrevs */);
188  SmallVector<uint64_t, 64> TypeVals;
189
190  uint64_t NumBits = Log2_32_Ceil(VE.getTypes().size()+1);
191
192  // Abbrev for TYPE_CODE_POINTER.
193  BitCodeAbbrev *Abbv = new BitCodeAbbrev();
194  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_POINTER));
195  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
196  Abbv->Add(BitCodeAbbrevOp(0));  // Addrspace = 0
197  unsigned PtrAbbrev = Stream.EmitAbbrev(Abbv);
198
199  // Abbrev for TYPE_CODE_FUNCTION.
200  Abbv = new BitCodeAbbrev();
201  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_FUNCTION));
202  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // isvararg
203  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
204  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
205
206  unsigned FunctionAbbrev = Stream.EmitAbbrev(Abbv);
207
208  // Abbrev for TYPE_CODE_STRUCT_ANON.
209  Abbv = new BitCodeAbbrev();
210  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_ANON));
211  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // ispacked
212  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
213  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
214
215  unsigned StructAnonAbbrev = Stream.EmitAbbrev(Abbv);
216
217  // Abbrev for TYPE_CODE_STRUCT_NAME.
218  Abbv = new BitCodeAbbrev();
219  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_NAME));
220  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
221  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
222  unsigned StructNameAbbrev = Stream.EmitAbbrev(Abbv);
223
224  // Abbrev for TYPE_CODE_STRUCT_NAMED.
225  Abbv = new BitCodeAbbrev();
226  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_NAMED));
227  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // ispacked
228  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
229  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
230
231  unsigned StructNamedAbbrev = Stream.EmitAbbrev(Abbv);
232
233  // Abbrev for TYPE_CODE_ARRAY.
234  Abbv = new BitCodeAbbrev();
235  Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_ARRAY));
236  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // size
237  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
238
239  unsigned ArrayAbbrev = Stream.EmitAbbrev(Abbv);
240
241  // Emit an entry count so the reader can reserve space.
242  TypeVals.push_back(TypeList.size());
243  Stream.EmitRecord(bitc::TYPE_CODE_NUMENTRY, TypeVals);
244  TypeVals.clear();
245
246  // Loop over all of the types, emitting each in turn.
247  for (unsigned i = 0, e = TypeList.size(); i != e; ++i) {
248    Type *T = TypeList[i];
249    int AbbrevToUse = 0;
250    unsigned Code = 0;
251
252    switch (T->getTypeID()) {
253    default: llvm_unreachable("Unknown type!");
254    case Type::VoidTyID:      Code = bitc::TYPE_CODE_VOID;      break;
255    case Type::HalfTyID:      Code = bitc::TYPE_CODE_HALF;      break;
256    case Type::FloatTyID:     Code = bitc::TYPE_CODE_FLOAT;     break;
257    case Type::DoubleTyID:    Code = bitc::TYPE_CODE_DOUBLE;    break;
258    case Type::X86_FP80TyID:  Code = bitc::TYPE_CODE_X86_FP80;  break;
259    case Type::FP128TyID:     Code = bitc::TYPE_CODE_FP128;     break;
260    case Type::PPC_FP128TyID: Code = bitc::TYPE_CODE_PPC_FP128; break;
261    case Type::LabelTyID:     Code = bitc::TYPE_CODE_LABEL;     break;
262    case Type::MetadataTyID:  Code = bitc::TYPE_CODE_METADATA;  break;
263    case Type::X86_MMXTyID:   Code = bitc::TYPE_CODE_X86_MMX;   break;
264    case Type::IntegerTyID:
265      // INTEGER: [width]
266      Code = bitc::TYPE_CODE_INTEGER;
267      TypeVals.push_back(cast<IntegerType>(T)->getBitWidth());
268      break;
269    case Type::PointerTyID: {
270      PointerType *PTy = cast<PointerType>(T);
271      // POINTER: [pointee type, address space]
272      Code = bitc::TYPE_CODE_POINTER;
273      TypeVals.push_back(VE.getTypeID(PTy->getElementType()));
274      unsigned AddressSpace = PTy->getAddressSpace();
275      TypeVals.push_back(AddressSpace);
276      if (AddressSpace == 0) AbbrevToUse = PtrAbbrev;
277      break;
278    }
279    case Type::FunctionTyID: {
280      FunctionType *FT = cast<FunctionType>(T);
281      // FUNCTION: [isvararg, retty, paramty x N]
282      Code = bitc::TYPE_CODE_FUNCTION;
283      TypeVals.push_back(FT->isVarArg());
284      TypeVals.push_back(VE.getTypeID(FT->getReturnType()));
285      for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i)
286        TypeVals.push_back(VE.getTypeID(FT->getParamType(i)));
287      AbbrevToUse = FunctionAbbrev;
288      break;
289    }
290    case Type::StructTyID: {
291      StructType *ST = cast<StructType>(T);
292      // STRUCT: [ispacked, eltty x N]
293      TypeVals.push_back(ST->isPacked());
294      // Output all of the element types.
295      for (StructType::element_iterator I = ST->element_begin(),
296           E = ST->element_end(); I != E; ++I)
297        TypeVals.push_back(VE.getTypeID(*I));
298
299      if (ST->isLiteral()) {
300        Code = bitc::TYPE_CODE_STRUCT_ANON;
301        AbbrevToUse = StructAnonAbbrev;
302      } else {
303        if (ST->isOpaque()) {
304          Code = bitc::TYPE_CODE_OPAQUE;
305        } else {
306          Code = bitc::TYPE_CODE_STRUCT_NAMED;
307          AbbrevToUse = StructNamedAbbrev;
308        }
309
310        // Emit the name if it is present.
311        if (!ST->getName().empty())
312          WriteStringRecord(bitc::TYPE_CODE_STRUCT_NAME, ST->getName(),
313                            StructNameAbbrev, Stream);
314      }
315      break;
316    }
317    case Type::ArrayTyID: {
318      ArrayType *AT = cast<ArrayType>(T);
319      // ARRAY: [numelts, eltty]
320      Code = bitc::TYPE_CODE_ARRAY;
321      TypeVals.push_back(AT->getNumElements());
322      TypeVals.push_back(VE.getTypeID(AT->getElementType()));
323      AbbrevToUse = ArrayAbbrev;
324      break;
325    }
326    case Type::VectorTyID: {
327      VectorType *VT = cast<VectorType>(T);
328      // VECTOR [numelts, eltty]
329      Code = bitc::TYPE_CODE_VECTOR;
330      TypeVals.push_back(VT->getNumElements());
331      TypeVals.push_back(VE.getTypeID(VT->getElementType()));
332      break;
333    }
334    }
335
336    // Emit the finished record.
337    Stream.EmitRecord(Code, TypeVals, AbbrevToUse);
338    TypeVals.clear();
339  }
340
341  Stream.ExitBlock();
342}
343
344static unsigned getEncodedLinkage(const GlobalValue &GV) {
345  switch (GV.getLinkage()) {
346  case GlobalValue::ExternalLinkage:
347    return 0;
348  case GlobalValue::WeakAnyLinkage:
349    return 1;
350  case GlobalValue::AppendingLinkage:
351    return 2;
352  case GlobalValue::InternalLinkage:
353    return 3;
354  case GlobalValue::LinkOnceAnyLinkage:
355    return 4;
356  case GlobalValue::ExternalWeakLinkage:
357    return 7;
358  case GlobalValue::CommonLinkage:
359    return 8;
360  case GlobalValue::PrivateLinkage:
361    return 9;
362  case GlobalValue::WeakODRLinkage:
363    return 10;
364  case GlobalValue::LinkOnceODRLinkage:
365    return 11;
366  case GlobalValue::AvailableExternallyLinkage:
367    return 12;
368  }
369  llvm_unreachable("Invalid linkage");
370}
371
372static unsigned getEncodedVisibility(const GlobalValue &GV) {
373  switch (GV.getVisibility()) {
374  case GlobalValue::DefaultVisibility:   return 0;
375  case GlobalValue::HiddenVisibility:    return 1;
376  case GlobalValue::ProtectedVisibility: return 2;
377  }
378  llvm_unreachable("Invalid visibility");
379}
380
381static unsigned getEncodedThreadLocalMode(const GlobalVariable &GV) {
382  switch (GV.getThreadLocalMode()) {
383    case GlobalVariable::NotThreadLocal:         return 0;
384    case GlobalVariable::GeneralDynamicTLSModel: return 1;
385    case GlobalVariable::LocalDynamicTLSModel:   return 2;
386    case GlobalVariable::InitialExecTLSModel:    return 3;
387    case GlobalVariable::LocalExecTLSModel:      return 4;
388  }
389  llvm_unreachable("Invalid TLS model");
390}
391
392// Emit top-level description of module, including target triple, inline asm,
393// descriptors for global variables, and function prototype info.
394static void WriteModuleInfo(const Module *M,
395                            const llvm_3_2::ValueEnumerator &VE,
396                            BitstreamWriter &Stream) {
397  // Emit various pieces of data attached to a module.
398  if (!M->getTargetTriple().empty())
399    WriteStringRecord(bitc::MODULE_CODE_TRIPLE, M->getTargetTriple(),
400                      0/*TODO*/, Stream);
401  const std::string &DL = M->getDataLayoutStr();
402  if (!DL.empty())
403    WriteStringRecord(bitc::MODULE_CODE_DATALAYOUT, DL, 0 /*TODO*/, Stream);
404  if (!M->getModuleInlineAsm().empty())
405    WriteStringRecord(bitc::MODULE_CODE_ASM, M->getModuleInlineAsm(),
406                      0/*TODO*/, Stream);
407
408  // Emit information about sections and GC, computing how many there are. Also
409  // compute the maximum alignment value.
410  std::map<std::string, unsigned> SectionMap;
411  std::map<std::string, unsigned> GCMap;
412  unsigned MaxAlignment = 0;
413  unsigned MaxGlobalType = 0;
414  for (const GlobalValue &GV : M->globals()) {
415    MaxAlignment = std::max(MaxAlignment, GV.getAlignment());
416    MaxGlobalType = std::max(MaxGlobalType, VE.getTypeID(GV.getType()));
417    if (GV.hasSection()) {
418      // Give section names unique ID's.
419      unsigned &Entry = SectionMap[GV.getSection()];
420      if (!Entry) {
421        WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, GV.getSection(),
422                          0/*TODO*/, Stream);
423        Entry = SectionMap.size();
424      }
425    }
426  }
427  for (const Function &F : *M) {
428    MaxAlignment = std::max(MaxAlignment, F.getAlignment());
429    if (F.hasSection()) {
430      // Give section names unique ID's.
431      unsigned &Entry = SectionMap[F.getSection()];
432      if (!Entry) {
433        WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F.getSection(),
434                          0/*TODO*/, Stream);
435        Entry = SectionMap.size();
436      }
437    }
438    if (F.hasGC()) {
439      // Same for GC names.
440      unsigned &Entry = GCMap[F.getGC()];
441      if (!Entry) {
442        WriteStringRecord(bitc::MODULE_CODE_GCNAME, F.getGC(),
443                          0/*TODO*/, Stream);
444        Entry = GCMap.size();
445      }
446    }
447  }
448
449  // Emit abbrev for globals, now that we know # sections and max alignment.
450  unsigned SimpleGVarAbbrev = 0;
451  if (!M->global_empty()) {
452    // Add an abbrev for common globals with no visibility or thread localness.
453    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
454    Abbv->Add(BitCodeAbbrevOp(bitc::MODULE_CODE_GLOBALVAR));
455    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
456                              Log2_32_Ceil(MaxGlobalType+1)));
457    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));      // Constant.
458    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));        // Initializer.
459    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));      // Linkage.
460    if (MaxAlignment == 0)                                      // Alignment.
461      Abbv->Add(BitCodeAbbrevOp(0));
462    else {
463      unsigned MaxEncAlignment = Log2_32(MaxAlignment)+1;
464      Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
465                               Log2_32_Ceil(MaxEncAlignment+1)));
466    }
467    if (SectionMap.empty())                                    // Section.
468      Abbv->Add(BitCodeAbbrevOp(0));
469    else
470      Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
471                               Log2_32_Ceil(SectionMap.size()+1)));
472    // Don't bother emitting vis + thread local.
473    SimpleGVarAbbrev = Stream.EmitAbbrev(Abbv);
474  }
475
476  // Emit the global variable information.
477  SmallVector<unsigned, 64> Vals;
478  for (const GlobalVariable &GV : M->globals()) {
479    unsigned AbbrevToUse = 0;
480
481    // GLOBALVAR: [type, isconst, initid,
482    //             linkage, alignment, section, visibility, threadlocal,
483    //             unnamed_addr]
484    Vals.push_back(VE.getTypeID(GV.getType()));
485    Vals.push_back(GV.isConstant());
486    Vals.push_back(GV.isDeclaration() ? 0 :
487                   (VE.getValueID(GV.getInitializer()) + 1));
488    Vals.push_back(getEncodedLinkage(GV));
489    Vals.push_back(Log2_32(GV.getAlignment())+1);
490    Vals.push_back(GV.hasSection() ? SectionMap[GV.getSection()] : 0);
491    if (GV.isThreadLocal() ||
492        GV.getVisibility() != GlobalValue::DefaultVisibility ||
493        GV.hasUnnamedAddr() || GV.isExternallyInitialized()) {
494      Vals.push_back(getEncodedVisibility(GV));
495      Vals.push_back(getEncodedThreadLocalMode(GV));
496      Vals.push_back(GV.hasUnnamedAddr());
497      Vals.push_back(GV.isExternallyInitialized());
498    } else {
499      AbbrevToUse = SimpleGVarAbbrev;
500    }
501
502    Stream.EmitRecord(bitc::MODULE_CODE_GLOBALVAR, Vals, AbbrevToUse);
503    Vals.clear();
504  }
505
506  // Emit the function proto information.
507  for (const Function &F : *M) {
508    // FUNCTION:  [type, callingconv, isproto, linkage, paramattrs, alignment,
509    //             section, visibility, gc, unnamed_addr]
510    Vals.push_back(VE.getTypeID(F.getType()));
511    Vals.push_back(F.getCallingConv());
512    Vals.push_back(F.isDeclaration());
513    Vals.push_back(getEncodedLinkage(F));
514    Vals.push_back(VE.getAttributeID(F.getAttributes()));
515    Vals.push_back(Log2_32(F.getAlignment())+1);
516    Vals.push_back(F.hasSection() ? SectionMap[F.getSection()] : 0);
517    Vals.push_back(getEncodedVisibility(F));
518    Vals.push_back(F.hasGC() ? GCMap[F.getGC()] : 0);
519    Vals.push_back(F.hasUnnamedAddr());
520
521    unsigned AbbrevToUse = 0;
522    Stream.EmitRecord(bitc::MODULE_CODE_FUNCTION, Vals, AbbrevToUse);
523    Vals.clear();
524  }
525
526  // Emit the alias information.
527  for (const GlobalAlias &A : M->aliases()) {
528    // ALIAS: [alias type, aliasee val#, linkage, visibility]
529    Vals.push_back(VE.getTypeID(A.getType()));
530    Vals.push_back(VE.getValueID(A.getAliasee()));
531    Vals.push_back(getEncodedLinkage(A));
532    Vals.push_back(getEncodedVisibility(A));
533    unsigned AbbrevToUse = 0;
534    Stream.EmitRecord(bitc::MODULE_CODE_ALIAS, Vals, AbbrevToUse);
535    Vals.clear();
536  }
537}
538
539static uint64_t GetOptimizationFlags(const Value *V) {
540  uint64_t Flags = 0;
541
542  if (const auto *OBO = dyn_cast<OverflowingBinaryOperator>(V)) {
543    if (OBO->hasNoSignedWrap())
544      Flags |= 1 << bitc::OBO_NO_SIGNED_WRAP;
545    if (OBO->hasNoUnsignedWrap())
546      Flags |= 1 << bitc::OBO_NO_UNSIGNED_WRAP;
547  } else if (const auto *PEO = dyn_cast<PossiblyExactOperator>(V)) {
548    if (PEO->isExact())
549      Flags |= 1 << bitc::PEO_EXACT;
550  } else if (const auto *FPMO = dyn_cast<FPMathOperator>(V)) {
551    // FIXME(srhines): We don't handle fast math in llvm-rs-cc today.
552    if (false) {
553      if (FPMO->hasUnsafeAlgebra())
554        Flags |= FastMathFlags::UnsafeAlgebra;
555      if (FPMO->hasNoNaNs())
556        Flags |= FastMathFlags::NoNaNs;
557      if (FPMO->hasNoInfs())
558        Flags |= FastMathFlags::NoInfs;
559      if (FPMO->hasNoSignedZeros())
560        Flags |= FastMathFlags::NoSignedZeros;
561      if (FPMO->hasAllowReciprocal())
562        Flags |= FastMathFlags::AllowReciprocal;
563    }
564  }
565
566  return Flags;
567}
568
569static void WriteValueAsMetadata(const ValueAsMetadata *MD,
570                                 const llvm_3_2::ValueEnumerator &VE,
571                                 BitstreamWriter &Stream,
572                                 SmallVectorImpl<uint64_t> &Record) {
573  // Mimic an MDNode with a value as one operand.
574  Value *V = MD->getValue();
575  Record.push_back(VE.getTypeID(V->getType()));
576  Record.push_back(VE.getValueID(V));
577  Stream.EmitRecord(bitc::METADATA_OLD_NODE, Record, 0);
578  Record.clear();
579}
580
581static void WriteMDTuple(const MDTuple *N, const llvm_3_2::ValueEnumerator &VE,
582                         BitstreamWriter &Stream,
583                         SmallVectorImpl<uint64_t> &Record, unsigned Abbrev) {
584  for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
585    Metadata *MD = N->getOperand(i);
586    assert(!(MD && isa<LocalAsMetadata>(MD)) &&
587           "Unexpected function-local metadata");
588    if (!MD) {
589      // TODO(srhines): I don't believe this case can exist for RS.
590      Record.push_back(VE.getTypeID(llvm::Type::getVoidTy(N->getContext())));
591      Record.push_back(0);
592    } else if (const auto *MDC = dyn_cast<ConstantAsMetadata>(MD)) {
593      Record.push_back(VE.getTypeID(MDC->getType()));
594      Record.push_back(VE.getValueID(MDC->getValue()));
595    } else {
596      Record.push_back(VE.getTypeID(
597          llvm::Type::getMetadataTy(N->getContext())));
598      Record.push_back(VE.getMetadataID(MD));
599    }
600  }
601  Stream.EmitRecord(bitc::METADATA_OLD_NODE, Record, Abbrev);
602  Record.clear();
603}
604
605/*static void WriteMDLocation(const MDLocation *N, const llvm_3_2::ValueEnumerator &VE,
606                            BitstreamWriter &Stream,
607                            SmallVectorImpl<uint64_t> &Record,
608                            unsigned Abbrev) {
609  Record.push_back(N->isDistinct());
610  Record.push_back(N->getLine());
611  Record.push_back(N->getColumn());
612  Record.push_back(VE.getMetadataID(N->getScope()));
613  Record.push_back(VE.getMetadataOrNullID(N->getInlinedAt()));
614
615  Stream.EmitRecord(bitc::METADATA_LOCATION, Record, Abbrev);
616  Record.clear();
617}
618
619static void WriteGenericDebugNode(const GenericDebugNode *,
620                                  const llvm_3_2::ValueEnumerator &, BitstreamWriter &,
621                                  SmallVectorImpl<uint64_t> &, unsigned) {
622  llvm_unreachable("unimplemented");
623}*/
624
625static void WriteModuleMetadata(const Module *M,
626                                const llvm_3_2::ValueEnumerator &VE,
627                                BitstreamWriter &Stream) {
628  const auto &MDs = VE.getMDs();
629  if (MDs.empty() && M->named_metadata_empty())
630    return;
631
632  // RenderScript files *ALWAYS* have metadata!
633  Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
634
635  unsigned MDSAbbrev = 0;
636  if (VE.hasMDString()) {
637    // Abbrev for METADATA_STRING.
638    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
639    Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_STRING));
640    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
641    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
642    MDSAbbrev = Stream.EmitAbbrev(Abbv);
643  }
644
645  unsigned MDLocationAbbrev = 0;
646  if (VE.hasMDLocation()) {
647    // TODO(srhines): Should be unreachable for RenderScript.
648    // Abbrev for METADATA_LOCATION.
649    //
650    // Assume the column is usually under 128, and always output the inlined-at
651    // location (it's never more expensive than building an array size 1).
652    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
653    Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_LOCATION));
654    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
655    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
656    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
657    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
658    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
659    MDLocationAbbrev = Stream.EmitAbbrev(Abbv);
660  }
661
662  unsigned NameAbbrev = 0;
663  if (!M->named_metadata_empty()) {
664    // Abbrev for METADATA_NAME.
665    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
666    Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_NAME));
667    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
668    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
669    NameAbbrev = Stream.EmitAbbrev(Abbv);
670  }
671
672  unsigned MDTupleAbbrev = 0;
673  //unsigned GenericDebugNodeAbbrev = 0;
674  SmallVector<uint64_t, 64> Record;
675  for (const Metadata *MD : MDs) {
676    if (const MDNode *N = dyn_cast<MDNode>(MD)) {
677      switch (N->getMetadataID()) {
678      default:
679        llvm_unreachable("Invalid MDNode subclass");
680#define HANDLE_SPECIALIZED_MDNODE_LEAF(CLASS)
681#define HANDLE_MDNODE_LEAF(CLASS)                                              \
682  case Metadata::CLASS##Kind:                                                  \
683    Write##CLASS(cast<CLASS>(N), VE, Stream, Record, CLASS##Abbrev);           \
684    continue;
685#include "llvm/IR/Metadata.def"
686      }
687    }
688    if (const auto *MDC = dyn_cast<ConstantAsMetadata>(MD)) {
689      WriteValueAsMetadata(MDC, VE, Stream, Record);
690      continue;
691    }
692    const MDString *MDS = cast<MDString>(MD);
693    // Code: [strchar x N]
694    Record.append(MDS->bytes_begin(), MDS->bytes_end());
695
696    // Emit the finished record.
697    Stream.EmitRecord(bitc::METADATA_STRING, Record, MDSAbbrev);
698    Record.clear();
699  }
700
701  // Write named metadata.
702  for (const NamedMDNode &NMD : M->named_metadata()) {
703    // Write name.
704    StringRef Str = NMD.getName();
705    Record.append(Str.bytes_begin(), Str.bytes_end());
706    Stream.EmitRecord(bitc::METADATA_NAME, Record, NameAbbrev);
707    Record.clear();
708
709    // Write named metadata operands.
710    for (const MDNode *N : NMD.operands())
711      Record.push_back(VE.getMetadataID(N));
712    Stream.EmitRecord(bitc::METADATA_NAMED_NODE, Record, 0);
713    Record.clear();
714  }
715
716  Stream.ExitBlock();
717}
718
719static void WriteFunctionLocalMetadata(const Function &F,
720                                       const llvm_3_2::ValueEnumerator &VE,
721                                       BitstreamWriter &Stream) {
722  bool StartedMetadataBlock = false;
723  SmallVector<uint64_t, 64> Record;
724  const SmallVectorImpl<const LocalAsMetadata *> &MDs =
725      VE.getFunctionLocalMDs();
726  for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
727    assert(MDs[i] && "Expected valid function-local metadata");
728    if (!StartedMetadataBlock) {
729      Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
730      StartedMetadataBlock = true;
731    }
732    WriteValueAsMetadata(MDs[i], VE, Stream, Record);
733  }
734
735  if (StartedMetadataBlock)
736    Stream.ExitBlock();
737}
738
739static void WriteMetadataAttachment(const Function &F,
740                                    const llvm_3_2::ValueEnumerator &VE,
741                                    BitstreamWriter &Stream) {
742  Stream.EnterSubblock(bitc::METADATA_ATTACHMENT_ID, 3);
743
744  SmallVector<uint64_t, 64> Record;
745
746  // Write metadata attachments
747  // METADATA_ATTACHMENT - [m x [value, [n x [id, mdnode]]]
748  SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
749
750  for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
751    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
752         I != E; ++I) {
753      MDs.clear();
754      I->getAllMetadataOtherThanDebugLoc(MDs);
755
756      // If no metadata, ignore instruction.
757      if (MDs.empty()) continue;
758
759      Record.push_back(VE.getInstructionID(I));
760
761      for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
762        Record.push_back(MDs[i].first);
763        Record.push_back(VE.getMetadataID(MDs[i].second));
764      }
765      Stream.EmitRecord(bitc::METADATA_ATTACHMENT, Record, 0);
766      Record.clear();
767    }
768
769  Stream.ExitBlock();
770}
771
772static void WriteModuleMetadataStore(const Module *M, BitstreamWriter &Stream) {
773  SmallVector<uint64_t, 64> Record;
774
775  // Write metadata kinds
776  // METADATA_KIND - [n x [id, name]]
777  SmallVector<StringRef, 4> Names;
778  M->getMDKindNames(Names);
779
780  if (Names.empty()) return;
781
782  Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
783
784  for (unsigned MDKindID = 0, e = Names.size(); MDKindID != e; ++MDKindID) {
785    Record.push_back(MDKindID);
786    StringRef KName = Names[MDKindID];
787    Record.append(KName.begin(), KName.end());
788
789    Stream.EmitRecord(bitc::METADATA_KIND, Record, 0);
790    Record.clear();
791  }
792
793  Stream.ExitBlock();
794}
795
796static void emitSignedInt64(SmallVectorImpl<uint64_t> &Vals, uint64_t V) {
797  if ((int64_t)V >= 0)
798    Vals.push_back(V << 1);
799  else
800    Vals.push_back((-V << 1) | 1);
801}
802
803static void WriteConstants(unsigned FirstVal, unsigned LastVal,
804                           const llvm_3_2::ValueEnumerator &VE,
805                           BitstreamWriter &Stream, bool isGlobal) {
806  if (FirstVal == LastVal) return;
807
808  Stream.EnterSubblock(bitc::CONSTANTS_BLOCK_ID, 4);
809
810  unsigned AggregateAbbrev = 0;
811  unsigned String8Abbrev = 0;
812  unsigned CString7Abbrev = 0;
813  unsigned CString6Abbrev = 0;
814  // If this is a constant pool for the module, emit module-specific abbrevs.
815  if (isGlobal) {
816    // Abbrev for CST_CODE_AGGREGATE.
817    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
818    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_AGGREGATE));
819    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
820    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, Log2_32_Ceil(LastVal+1)));
821    AggregateAbbrev = Stream.EmitAbbrev(Abbv);
822
823    // Abbrev for CST_CODE_STRING.
824    Abbv = new BitCodeAbbrev();
825    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_STRING));
826    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
827    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
828    String8Abbrev = Stream.EmitAbbrev(Abbv);
829    // Abbrev for CST_CODE_CSTRING.
830    Abbv = new BitCodeAbbrev();
831    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
832    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
833    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
834    CString7Abbrev = Stream.EmitAbbrev(Abbv);
835    // Abbrev for CST_CODE_CSTRING.
836    Abbv = new BitCodeAbbrev();
837    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
838    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
839    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
840    CString6Abbrev = Stream.EmitAbbrev(Abbv);
841  }
842
843  SmallVector<uint64_t, 64> Record;
844
845  const llvm_3_2::ValueEnumerator::ValueList &Vals = VE.getValues();
846  Type *LastTy = nullptr;
847  for (unsigned i = FirstVal; i != LastVal; ++i) {
848    const Value *V = Vals[i].first;
849    // If we need to switch types, do so now.
850    if (V->getType() != LastTy) {
851      LastTy = V->getType();
852      Record.push_back(VE.getTypeID(LastTy));
853      Stream.EmitRecord(bitc::CST_CODE_SETTYPE, Record,
854                        CONSTANTS_SETTYPE_ABBREV);
855      Record.clear();
856    }
857
858    if (const InlineAsm *IA = dyn_cast<InlineAsm>(V)) {
859      Record.push_back(unsigned(IA->hasSideEffects()) |
860                       unsigned(IA->isAlignStack()) << 1 |
861                       unsigned(IA->getDialect()&1) << 2);
862
863      // Add the asm string.
864      const std::string &AsmStr = IA->getAsmString();
865      Record.push_back(AsmStr.size());
866      for (unsigned i = 0, e = AsmStr.size(); i != e; ++i)
867        Record.push_back(AsmStr[i]);
868
869      // Add the constraint string.
870      const std::string &ConstraintStr = IA->getConstraintString();
871      Record.push_back(ConstraintStr.size());
872      for (unsigned i = 0, e = ConstraintStr.size(); i != e; ++i)
873        Record.push_back(ConstraintStr[i]);
874      Stream.EmitRecord(bitc::CST_CODE_INLINEASM, Record);
875      Record.clear();
876      continue;
877    }
878    const Constant *C = cast<Constant>(V);
879    unsigned Code = -1U;
880    unsigned AbbrevToUse = 0;
881    if (C->isNullValue()) {
882      Code = bitc::CST_CODE_NULL;
883    } else if (isa<UndefValue>(C)) {
884      Code = bitc::CST_CODE_UNDEF;
885    } else if (const ConstantInt *IV = dyn_cast<ConstantInt>(C)) {
886      if (IV->getBitWidth() <= 64) {
887        uint64_t V = IV->getSExtValue();
888        emitSignedInt64(Record, V);
889        Code = bitc::CST_CODE_INTEGER;
890        AbbrevToUse = CONSTANTS_INTEGER_ABBREV;
891      } else {                             // Wide integers, > 64 bits in size.
892        // We have an arbitrary precision integer value to write whose
893        // bit width is > 64. However, in canonical unsigned integer
894        // format it is likely that the high bits are going to be zero.
895        // So, we only write the number of active words.
896        unsigned NWords = IV->getValue().getActiveWords();
897        const uint64_t *RawWords = IV->getValue().getRawData();
898        for (unsigned i = 0; i != NWords; ++i) {
899          emitSignedInt64(Record, RawWords[i]);
900        }
901        Code = bitc::CST_CODE_WIDE_INTEGER;
902      }
903    } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
904      Code = bitc::CST_CODE_FLOAT;
905      Type *Ty = CFP->getType();
906      if (Ty->isHalfTy() || Ty->isFloatTy() || Ty->isDoubleTy()) {
907        Record.push_back(CFP->getValueAPF().bitcastToAPInt().getZExtValue());
908      } else if (Ty->isX86_FP80Ty()) {
909        // api needed to prevent premature destruction
910        // bits are not in the same order as a normal i80 APInt, compensate.
911        APInt api = CFP->getValueAPF().bitcastToAPInt();
912        const uint64_t *p = api.getRawData();
913        Record.push_back((p[1] << 48) | (p[0] >> 16));
914        Record.push_back(p[0] & 0xffffLL);
915      } else if (Ty->isFP128Ty() || Ty->isPPC_FP128Ty()) {
916        APInt api = CFP->getValueAPF().bitcastToAPInt();
917        const uint64_t *p = api.getRawData();
918        Record.push_back(p[0]);
919        Record.push_back(p[1]);
920      } else {
921        assert (0 && "Unknown FP type!");
922      }
923    } else if (isa<ConstantDataSequential>(C) &&
924               cast<ConstantDataSequential>(C)->isString()) {
925      const ConstantDataSequential *Str = cast<ConstantDataSequential>(C);
926      // Emit constant strings specially.
927      unsigned NumElts = Str->getNumElements();
928      // If this is a null-terminated string, use the denser CSTRING encoding.
929      if (Str->isCString()) {
930        Code = bitc::CST_CODE_CSTRING;
931        --NumElts;  // Don't encode the null, which isn't allowed by char6.
932      } else {
933        Code = bitc::CST_CODE_STRING;
934        AbbrevToUse = String8Abbrev;
935      }
936      bool isCStr7 = Code == bitc::CST_CODE_CSTRING;
937      bool isCStrChar6 = Code == bitc::CST_CODE_CSTRING;
938      for (unsigned i = 0; i != NumElts; ++i) {
939        unsigned char V = Str->getElementAsInteger(i);
940        Record.push_back(V);
941        isCStr7 &= (V & 128) == 0;
942        if (isCStrChar6)
943          isCStrChar6 = BitCodeAbbrevOp::isChar6(V);
944      }
945
946      if (isCStrChar6)
947        AbbrevToUse = CString6Abbrev;
948      else if (isCStr7)
949        AbbrevToUse = CString7Abbrev;
950    } else if (const ConstantDataSequential *CDS =
951                  dyn_cast<ConstantDataSequential>(C)) {
952      Code = bitc::CST_CODE_DATA;
953      Type *EltTy = CDS->getType()->getElementType();
954      if (isa<IntegerType>(EltTy)) {
955        for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i)
956          Record.push_back(CDS->getElementAsInteger(i));
957      } else if (EltTy->isFloatTy()) {
958        for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
959          union { float F; uint32_t I; };
960          F = CDS->getElementAsFloat(i);
961          Record.push_back(I);
962        }
963      } else {
964        assert(EltTy->isDoubleTy() && "Unknown ConstantData element type");
965        for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
966          union { double F; uint64_t I; };
967          F = CDS->getElementAsDouble(i);
968          Record.push_back(I);
969        }
970      }
971    } else if (isa<ConstantArray>(C) || isa<ConstantStruct>(C) ||
972               isa<ConstantVector>(C)) {
973      Code = bitc::CST_CODE_AGGREGATE;
974      for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i)
975        Record.push_back(VE.getValueID(C->getOperand(i)));
976      AbbrevToUse = AggregateAbbrev;
977    } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
978      switch (CE->getOpcode()) {
979      default:
980        if (Instruction::isCast(CE->getOpcode())) {
981          Code = bitc::CST_CODE_CE_CAST;
982          Record.push_back(GetEncodedCastOpcode(CE->getOpcode()));
983          Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
984          Record.push_back(VE.getValueID(C->getOperand(0)));
985          AbbrevToUse = CONSTANTS_CE_CAST_Abbrev;
986        } else {
987          assert(CE->getNumOperands() == 2 && "Unknown constant expr!");
988          Code = bitc::CST_CODE_CE_BINOP;
989          Record.push_back(GetEncodedBinaryOpcode(CE->getOpcode()));
990          Record.push_back(VE.getValueID(C->getOperand(0)));
991          Record.push_back(VE.getValueID(C->getOperand(1)));
992          uint64_t Flags = GetOptimizationFlags(CE);
993          if (Flags != 0)
994            Record.push_back(Flags);
995        }
996        break;
997      case Instruction::GetElementPtr:
998        Code = bitc::CST_CODE_CE_GEP;
999        if (cast<GEPOperator>(C)->isInBounds())
1000          Code = bitc::CST_CODE_CE_INBOUNDS_GEP;
1001        for (unsigned i = 0, e = CE->getNumOperands(); i != e; ++i) {
1002          Record.push_back(VE.getTypeID(C->getOperand(i)->getType()));
1003          Record.push_back(VE.getValueID(C->getOperand(i)));
1004        }
1005        break;
1006      case Instruction::Select:
1007        Code = bitc::CST_CODE_CE_SELECT;
1008        Record.push_back(VE.getValueID(C->getOperand(0)));
1009        Record.push_back(VE.getValueID(C->getOperand(1)));
1010        Record.push_back(VE.getValueID(C->getOperand(2)));
1011        break;
1012      case Instruction::ExtractElement:
1013        Code = bitc::CST_CODE_CE_EXTRACTELT;
1014        Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
1015        Record.push_back(VE.getValueID(C->getOperand(0)));
1016        Record.push_back(VE.getValueID(C->getOperand(1)));
1017        break;
1018      case Instruction::InsertElement:
1019        Code = bitc::CST_CODE_CE_INSERTELT;
1020        Record.push_back(VE.getValueID(C->getOperand(0)));
1021        Record.push_back(VE.getValueID(C->getOperand(1)));
1022        Record.push_back(VE.getValueID(C->getOperand(2)));
1023        break;
1024      case Instruction::ShuffleVector:
1025        // If the return type and argument types are the same, this is a
1026        // standard shufflevector instruction.  If the types are different,
1027        // then the shuffle is widening or truncating the input vectors, and
1028        // the argument type must also be encoded.
1029        if (C->getType() == C->getOperand(0)->getType()) {
1030          Code = bitc::CST_CODE_CE_SHUFFLEVEC;
1031        } else {
1032          Code = bitc::CST_CODE_CE_SHUFVEC_EX;
1033          Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
1034        }
1035        Record.push_back(VE.getValueID(C->getOperand(0)));
1036        Record.push_back(VE.getValueID(C->getOperand(1)));
1037        Record.push_back(VE.getValueID(C->getOperand(2)));
1038        break;
1039      case Instruction::ICmp:
1040      case Instruction::FCmp:
1041        Code = bitc::CST_CODE_CE_CMP;
1042        Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
1043        Record.push_back(VE.getValueID(C->getOperand(0)));
1044        Record.push_back(VE.getValueID(C->getOperand(1)));
1045        Record.push_back(CE->getPredicate());
1046        break;
1047      }
1048    } else if (const BlockAddress *BA = dyn_cast<BlockAddress>(C)) {
1049      Code = bitc::CST_CODE_BLOCKADDRESS;
1050      Record.push_back(VE.getTypeID(BA->getFunction()->getType()));
1051      Record.push_back(VE.getValueID(BA->getFunction()));
1052      Record.push_back(VE.getGlobalBasicBlockID(BA->getBasicBlock()));
1053    } else {
1054#ifndef NDEBUG
1055      C->dump();
1056#endif
1057      llvm_unreachable("Unknown constant!");
1058    }
1059    Stream.EmitRecord(Code, Record, AbbrevToUse);
1060    Record.clear();
1061  }
1062
1063  Stream.ExitBlock();
1064}
1065
1066static void WriteModuleConstants(const llvm_3_2::ValueEnumerator &VE,
1067                                 BitstreamWriter &Stream) {
1068  const llvm_3_2::ValueEnumerator::ValueList &Vals = VE.getValues();
1069
1070  // Find the first constant to emit, which is the first non-globalvalue value.
1071  // We know globalvalues have been emitted by WriteModuleInfo.
1072  for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
1073    if (!isa<GlobalValue>(Vals[i].first)) {
1074      WriteConstants(i, Vals.size(), VE, Stream, true);
1075      return;
1076    }
1077  }
1078}
1079
1080/// PushValueAndType - The file has to encode both the value and type id for
1081/// many values, because we need to know what type to create for forward
1082/// references.  However, most operands are not forward references, so this type
1083/// field is not needed.
1084///
1085/// This function adds V's value ID to Vals.  If the value ID is higher than the
1086/// instruction ID, then it is a forward reference, and it also includes the
1087/// type ID.
1088static bool PushValueAndType(const Value *V, unsigned InstID,
1089                             SmallVector<unsigned, 64> &Vals,
1090                             llvm_3_2::ValueEnumerator &VE) {
1091  unsigned ValID = VE.getValueID(V);
1092  Vals.push_back(ValID);
1093  if (ValID >= InstID) {
1094    Vals.push_back(VE.getTypeID(V->getType()));
1095    return true;
1096  }
1097  return false;
1098}
1099
1100/// WriteInstruction - Emit an instruction to the specified stream.
1101static void WriteInstruction(const Instruction &I, unsigned InstID,
1102                             llvm_3_2::ValueEnumerator &VE,
1103                             BitstreamWriter &Stream,
1104                             SmallVector<unsigned, 64> &Vals) {
1105  unsigned Code = 0;
1106  unsigned AbbrevToUse = 0;
1107  VE.setInstructionID(&I);
1108  switch (I.getOpcode()) {
1109  default:
1110    if (Instruction::isCast(I.getOpcode())) {
1111      Code = bitc::FUNC_CODE_INST_CAST;
1112      if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1113        AbbrevToUse = FUNCTION_INST_CAST_ABBREV;
1114      Vals.push_back(VE.getTypeID(I.getType()));
1115      Vals.push_back(GetEncodedCastOpcode(I.getOpcode()));
1116    } else {
1117      assert(isa<BinaryOperator>(I) && "Unknown instruction!");
1118      Code = bitc::FUNC_CODE_INST_BINOP;
1119      if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1120        AbbrevToUse = FUNCTION_INST_BINOP_ABBREV;
1121      Vals.push_back(VE.getValueID(I.getOperand(1)));
1122      Vals.push_back(GetEncodedBinaryOpcode(I.getOpcode()));
1123      uint64_t Flags = GetOptimizationFlags(&I);
1124      if (Flags != 0) {
1125        if (AbbrevToUse == FUNCTION_INST_BINOP_ABBREV)
1126          AbbrevToUse = FUNCTION_INST_BINOP_FLAGS_ABBREV;
1127        Vals.push_back(Flags);
1128      }
1129    }
1130    break;
1131
1132  case Instruction::GetElementPtr:
1133    Code = bitc::FUNC_CODE_INST_GEP_OLD;
1134    if (cast<GEPOperator>(&I)->isInBounds())
1135      Code = bitc::FUNC_CODE_INST_INBOUNDS_GEP_OLD;
1136    for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1137      PushValueAndType(I.getOperand(i), InstID, Vals, VE);
1138    break;
1139  case Instruction::ExtractValue: {
1140    Code = bitc::FUNC_CODE_INST_EXTRACTVAL;
1141    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1142    const ExtractValueInst *EVI = cast<ExtractValueInst>(&I);
1143    for (const unsigned *i = EVI->idx_begin(), *e = EVI->idx_end(); i != e; ++i)
1144      Vals.push_back(*i);
1145    break;
1146  }
1147  case Instruction::InsertValue: {
1148    Code = bitc::FUNC_CODE_INST_INSERTVAL;
1149    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1150    PushValueAndType(I.getOperand(1), InstID, Vals, VE);
1151    const InsertValueInst *IVI = cast<InsertValueInst>(&I);
1152    for (const unsigned *i = IVI->idx_begin(), *e = IVI->idx_end(); i != e; ++i)
1153      Vals.push_back(*i);
1154    break;
1155  }
1156  case Instruction::Select:
1157    Code = bitc::FUNC_CODE_INST_VSELECT;
1158    PushValueAndType(I.getOperand(1), InstID, Vals, VE);
1159    Vals.push_back(VE.getValueID(I.getOperand(2)));
1160    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1161    break;
1162  case Instruction::ExtractElement:
1163    Code = bitc::FUNC_CODE_INST_EXTRACTELT;
1164    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1165    Vals.push_back(VE.getValueID(I.getOperand(1)));
1166    break;
1167  case Instruction::InsertElement:
1168    Code = bitc::FUNC_CODE_INST_INSERTELT;
1169    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1170    Vals.push_back(VE.getValueID(I.getOperand(1)));
1171    Vals.push_back(VE.getValueID(I.getOperand(2)));
1172    break;
1173  case Instruction::ShuffleVector:
1174    Code = bitc::FUNC_CODE_INST_SHUFFLEVEC;
1175    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1176    Vals.push_back(VE.getValueID(I.getOperand(1)));
1177    Vals.push_back(VE.getValueID(I.getOperand(2)));
1178    break;
1179  case Instruction::ICmp:
1180  case Instruction::FCmp:
1181    // compare returning Int1Ty or vector of Int1Ty
1182    Code = bitc::FUNC_CODE_INST_CMP2;
1183    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1184    Vals.push_back(VE.getValueID(I.getOperand(1)));
1185    Vals.push_back(cast<CmpInst>(I).getPredicate());
1186    break;
1187
1188  case Instruction::Ret:
1189    {
1190      Code = bitc::FUNC_CODE_INST_RET;
1191      unsigned NumOperands = I.getNumOperands();
1192      if (NumOperands == 0)
1193        AbbrevToUse = FUNCTION_INST_RET_VOID_ABBREV;
1194      else if (NumOperands == 1) {
1195        if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1196          AbbrevToUse = FUNCTION_INST_RET_VAL_ABBREV;
1197      } else {
1198        for (unsigned i = 0, e = NumOperands; i != e; ++i)
1199          PushValueAndType(I.getOperand(i), InstID, Vals, VE);
1200      }
1201    }
1202    break;
1203  case Instruction::Br:
1204    {
1205      Code = bitc::FUNC_CODE_INST_BR;
1206      const BranchInst &II = cast<BranchInst>(I);
1207      Vals.push_back(VE.getValueID(II.getSuccessor(0)));
1208      if (II.isConditional()) {
1209        Vals.push_back(VE.getValueID(II.getSuccessor(1)));
1210        Vals.push_back(VE.getValueID(II.getCondition()));
1211      }
1212    }
1213    break;
1214  case Instruction::Switch:
1215    {
1216      Code = bitc::FUNC_CODE_INST_SWITCH;
1217      const SwitchInst &SI = cast<SwitchInst>(I);
1218      Vals.push_back(VE.getTypeID(SI.getCondition()->getType()));
1219      Vals.push_back(VE.getValueID(SI.getCondition()));
1220      Vals.push_back(VE.getValueID(SI.getDefaultDest()));
1221      for (SwitchInst::ConstCaseIt i = SI.case_begin(), e = SI.case_end();
1222           i != e; ++i) {
1223        Vals.push_back(VE.getValueID(i.getCaseValue()));
1224        Vals.push_back(VE.getValueID(i.getCaseSuccessor()));
1225      }
1226    }
1227    break;
1228  case Instruction::IndirectBr:
1229    Code = bitc::FUNC_CODE_INST_INDIRECTBR;
1230    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1231    for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1232      Vals.push_back(VE.getValueID(I.getOperand(i)));
1233    break;
1234
1235  case Instruction::Invoke: {
1236    const InvokeInst *II = cast<InvokeInst>(&I);
1237    const Value *Callee(II->getCalledValue());
1238    PointerType *PTy = cast<PointerType>(Callee->getType());
1239    FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1240    Code = bitc::FUNC_CODE_INST_INVOKE;
1241
1242    Vals.push_back(VE.getAttributeID(II->getAttributes()));
1243    Vals.push_back(II->getCallingConv());
1244    Vals.push_back(VE.getValueID(II->getNormalDest()));
1245    Vals.push_back(VE.getValueID(II->getUnwindDest()));
1246    PushValueAndType(Callee, InstID, Vals, VE);
1247
1248    // Emit value #'s for the fixed parameters.
1249    for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
1250      Vals.push_back(VE.getValueID(I.getOperand(i)));  // fixed param.
1251
1252    // Emit type/value pairs for varargs params.
1253    if (FTy->isVarArg()) {
1254      for (unsigned i = FTy->getNumParams(), e = I.getNumOperands()-3;
1255           i != e; ++i)
1256        PushValueAndType(I.getOperand(i), InstID, Vals, VE); // vararg
1257    }
1258    break;
1259  }
1260  case Instruction::Resume:
1261    Code = bitc::FUNC_CODE_INST_RESUME;
1262    PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1263    break;
1264  case Instruction::Unreachable:
1265    Code = bitc::FUNC_CODE_INST_UNREACHABLE;
1266    AbbrevToUse = FUNCTION_INST_UNREACHABLE_ABBREV;
1267    break;
1268
1269  case Instruction::PHI: {
1270    const PHINode &PN = cast<PHINode>(I);
1271    Code = bitc::FUNC_CODE_INST_PHI;
1272    Vals.push_back(VE.getTypeID(PN.getType()));
1273    for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
1274      Vals.push_back(VE.getValueID(PN.getIncomingValue(i)));
1275      Vals.push_back(VE.getValueID(PN.getIncomingBlock(i)));
1276    }
1277    break;
1278  }
1279
1280  case Instruction::LandingPad: {
1281    const LandingPadInst &LP = cast<LandingPadInst>(I);
1282    Code = bitc::FUNC_CODE_INST_LANDINGPAD;
1283    Vals.push_back(VE.getTypeID(LP.getType()));
1284    PushValueAndType(LP.getPersonalityFn(), InstID, Vals, VE);
1285    Vals.push_back(LP.isCleanup());
1286    Vals.push_back(LP.getNumClauses());
1287    for (unsigned I = 0, E = LP.getNumClauses(); I != E; ++I) {
1288      if (LP.isCatch(I))
1289        Vals.push_back(LandingPadInst::Catch);
1290      else
1291        Vals.push_back(LandingPadInst::Filter);
1292      PushValueAndType(LP.getClause(I), InstID, Vals, VE);
1293    }
1294    break;
1295  }
1296
1297  case Instruction::Alloca: {
1298    Code = bitc::FUNC_CODE_INST_ALLOCA;
1299    Vals.push_back(VE.getTypeID(I.getType()));
1300    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1301    Vals.push_back(VE.getValueID(I.getOperand(0))); // size.
1302    Vals.push_back(Log2_32(cast<AllocaInst>(I).getAlignment())+1);
1303    break;
1304  }
1305
1306  case Instruction::Load:
1307    if (cast<LoadInst>(I).isAtomic()) {
1308      Code = bitc::FUNC_CODE_INST_LOADATOMIC;
1309      PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1310    } else {
1311      Code = bitc::FUNC_CODE_INST_LOAD;
1312      if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))  // ptr
1313        AbbrevToUse = FUNCTION_INST_LOAD_ABBREV;
1314    }
1315    Vals.push_back(Log2_32(cast<LoadInst>(I).getAlignment())+1);
1316    Vals.push_back(cast<LoadInst>(I).isVolatile());
1317    if (cast<LoadInst>(I).isAtomic()) {
1318      Vals.push_back(GetEncodedOrdering(cast<LoadInst>(I).getOrdering()));
1319      Vals.push_back(GetEncodedSynchScope(cast<LoadInst>(I).getSynchScope()));
1320    }
1321    break;
1322  case Instruction::Store:
1323    if (cast<StoreInst>(I).isAtomic())
1324      Code = bitc::FUNC_CODE_INST_STOREATOMIC;
1325    else
1326      Code = bitc::FUNC_CODE_INST_STORE;
1327    PushValueAndType(I.getOperand(1), InstID, Vals, VE);  // ptrty + ptr
1328    Vals.push_back(VE.getValueID(I.getOperand(0)));       // val.
1329    Vals.push_back(Log2_32(cast<StoreInst>(I).getAlignment())+1);
1330    Vals.push_back(cast<StoreInst>(I).isVolatile());
1331    if (cast<StoreInst>(I).isAtomic()) {
1332      Vals.push_back(GetEncodedOrdering(cast<StoreInst>(I).getOrdering()));
1333      Vals.push_back(GetEncodedSynchScope(cast<StoreInst>(I).getSynchScope()));
1334    }
1335    break;
1336  case Instruction::AtomicCmpXchg:
1337    Code = bitc::FUNC_CODE_INST_CMPXCHG;
1338    PushValueAndType(I.getOperand(0), InstID, Vals, VE);  // ptrty + ptr
1339    Vals.push_back(VE.getValueID(I.getOperand(1)));       // cmp.
1340    Vals.push_back(VE.getValueID(I.getOperand(2)));       // newval.
1341    Vals.push_back(cast<AtomicCmpXchgInst>(I).isVolatile());
1342    Vals.push_back(GetEncodedOrdering(
1343                     cast<AtomicCmpXchgInst>(I).getSuccessOrdering()));
1344    Vals.push_back(GetEncodedSynchScope(
1345                     cast<AtomicCmpXchgInst>(I).getSynchScope()));
1346    break;
1347  case Instruction::AtomicRMW:
1348    Code = bitc::FUNC_CODE_INST_ATOMICRMW;
1349    PushValueAndType(I.getOperand(0), InstID, Vals, VE);  // ptrty + ptr
1350    Vals.push_back(VE.getValueID(I.getOperand(1)));       // val.
1351    Vals.push_back(GetEncodedRMWOperation(
1352                     cast<AtomicRMWInst>(I).getOperation()));
1353    Vals.push_back(cast<AtomicRMWInst>(I).isVolatile());
1354    Vals.push_back(GetEncodedOrdering(cast<AtomicRMWInst>(I).getOrdering()));
1355    Vals.push_back(GetEncodedSynchScope(
1356                     cast<AtomicRMWInst>(I).getSynchScope()));
1357    break;
1358  case Instruction::Fence:
1359    Code = bitc::FUNC_CODE_INST_FENCE;
1360    Vals.push_back(GetEncodedOrdering(cast<FenceInst>(I).getOrdering()));
1361    Vals.push_back(GetEncodedSynchScope(cast<FenceInst>(I).getSynchScope()));
1362    break;
1363  case Instruction::Call: {
1364    const CallInst &CI = cast<CallInst>(I);
1365    PointerType *PTy = cast<PointerType>(CI.getCalledValue()->getType());
1366    FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1367
1368    Code = bitc::FUNC_CODE_INST_CALL;
1369
1370    Vals.push_back(VE.getAttributeID(CI.getAttributes()));
1371    Vals.push_back((CI.getCallingConv() << 1) | unsigned(CI.isTailCall()));
1372    PushValueAndType(CI.getCalledValue(), InstID, Vals, VE);  // Callee
1373
1374    // Emit value #'s for the fixed parameters.
1375    for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
1376      Vals.push_back(VE.getValueID(CI.getArgOperand(i)));  // fixed param.
1377
1378    // Emit type/value pairs for varargs params.
1379    if (FTy->isVarArg()) {
1380      for (unsigned i = FTy->getNumParams(), e = CI.getNumArgOperands();
1381           i != e; ++i)
1382        PushValueAndType(CI.getArgOperand(i), InstID, Vals, VE);  // varargs
1383    }
1384    break;
1385  }
1386  case Instruction::VAArg:
1387    Code = bitc::FUNC_CODE_INST_VAARG;
1388    Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));   // valistty
1389    Vals.push_back(VE.getValueID(I.getOperand(0))); // valist.
1390    Vals.push_back(VE.getTypeID(I.getType())); // restype.
1391    break;
1392  }
1393
1394  Stream.EmitRecord(Code, Vals, AbbrevToUse);
1395  Vals.clear();
1396}
1397
1398// Emit names for globals/functions etc.
1399static void WriteValueSymbolTable(const ValueSymbolTable &VST,
1400                                  const llvm_3_2::ValueEnumerator &VE,
1401                                  BitstreamWriter &Stream) {
1402  if (VST.empty()) return;
1403  Stream.EnterSubblock(bitc::VALUE_SYMTAB_BLOCK_ID, 4);
1404
1405  // FIXME: Set up the abbrev, we know how many values there are!
1406  // FIXME: We know if the type names can use 7-bit ascii.
1407  SmallVector<unsigned, 64> NameVals;
1408
1409  for (ValueSymbolTable::const_iterator SI = VST.begin(), SE = VST.end();
1410       SI != SE; ++SI) {
1411
1412    const ValueName &Name = *SI;
1413
1414    // Figure out the encoding to use for the name.
1415    bool is7Bit = true;
1416    bool isChar6 = true;
1417    for (const char *C = Name.getKeyData(), *E = C+Name.getKeyLength();
1418         C != E; ++C) {
1419      if (isChar6)
1420        isChar6 = BitCodeAbbrevOp::isChar6(*C);
1421      if ((unsigned char)*C & 128) {
1422        is7Bit = false;
1423        break;  // don't bother scanning the rest.
1424      }
1425    }
1426
1427    unsigned AbbrevToUse = VST_ENTRY_8_ABBREV;
1428
1429    // VST_ENTRY:   [valueid, namechar x N]
1430    // VST_BBENTRY: [bbid, namechar x N]
1431    unsigned Code;
1432    if (isa<BasicBlock>(SI->getValue())) {
1433      Code = bitc::VST_CODE_BBENTRY;
1434      if (isChar6)
1435        AbbrevToUse = VST_BBENTRY_6_ABBREV;
1436    } else {
1437      Code = bitc::VST_CODE_ENTRY;
1438      if (isChar6)
1439        AbbrevToUse = VST_ENTRY_6_ABBREV;
1440      else if (is7Bit)
1441        AbbrevToUse = VST_ENTRY_7_ABBREV;
1442    }
1443
1444    NameVals.push_back(VE.getValueID(SI->getValue()));
1445    for (const char *P = Name.getKeyData(),
1446         *E = Name.getKeyData()+Name.getKeyLength(); P != E; ++P)
1447      NameVals.push_back((unsigned char)*P);
1448
1449    // Emit the finished record.
1450    Stream.EmitRecord(Code, NameVals, AbbrevToUse);
1451    NameVals.clear();
1452  }
1453  Stream.ExitBlock();
1454}
1455
1456static void WriteUseList(llvm_3_2::ValueEnumerator &VE, UseListOrder &&Order,
1457                         BitstreamWriter &Stream) {
1458  assert(Order.Shuffle.size() >= 2 && "Shuffle too small");
1459  unsigned Code;
1460  if (isa<BasicBlock>(Order.V))
1461    Code = bitc::USELIST_CODE_BB;
1462  else
1463    Code = bitc::USELIST_CODE_DEFAULT;
1464
1465  SmallVector<uint64_t, 64> Record;
1466  for (unsigned I : Order.Shuffle)
1467    Record.push_back(I);
1468  Record.push_back(VE.getValueID(Order.V));
1469  Stream.EmitRecord(Code, Record);
1470}
1471
1472static void WriteUseListBlock(const Function *F, llvm_3_2::ValueEnumerator &VE,
1473                              BitstreamWriter &Stream) {
1474  auto hasMore = [&]() {
1475    return !VE.UseListOrders.empty() && VE.UseListOrders.back().F == F;
1476  };
1477  if (!hasMore())
1478    // Nothing to do.
1479    return;
1480
1481  Stream.EnterSubblock(bitc::USELIST_BLOCK_ID, 3);
1482  while (hasMore()) {
1483    WriteUseList(VE, std::move(VE.UseListOrders.back()), Stream);
1484    VE.UseListOrders.pop_back();
1485  }
1486  Stream.ExitBlock();
1487}
1488
1489/// WriteFunction - Emit a function body to the module stream.
1490static void WriteFunction(const Function &F, llvm_3_2::ValueEnumerator &VE,
1491                          BitstreamWriter &Stream) {
1492  Stream.EnterSubblock(bitc::FUNCTION_BLOCK_ID, 4);
1493  VE.incorporateFunction(F);
1494
1495  SmallVector<unsigned, 64> Vals;
1496
1497  // Emit the number of basic blocks, so the reader can create them ahead of
1498  // time.
1499  Vals.push_back(VE.getBasicBlocks().size());
1500  Stream.EmitRecord(bitc::FUNC_CODE_DECLAREBLOCKS, Vals);
1501  Vals.clear();
1502
1503  // If there are function-local constants, emit them now.
1504  unsigned CstStart, CstEnd;
1505  VE.getFunctionConstantRange(CstStart, CstEnd);
1506  WriteConstants(CstStart, CstEnd, VE, Stream, false);
1507
1508  // If there is function-local metadata, emit it now.
1509  WriteFunctionLocalMetadata(F, VE, Stream);
1510
1511  // Keep a running idea of what the instruction ID is.
1512  unsigned InstID = CstEnd;
1513
1514  bool NeedsMetadataAttachment = false;
1515
1516  DebugLoc LastDL;
1517
1518  // Finally, emit all the instructions, in order.
1519  for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
1520    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
1521         I != E; ++I) {
1522      WriteInstruction(*I, InstID, VE, Stream, Vals);
1523
1524      if (!I->getType()->isVoidTy())
1525        ++InstID;
1526
1527      // If the instruction has metadata, write a metadata attachment later.
1528      NeedsMetadataAttachment |= I->hasMetadataOtherThanDebugLoc();
1529
1530      // If the instruction has a debug location, emit it.
1531      DebugLoc DL = I->getDebugLoc();
1532      if (DL.isUnknown()) {
1533        // nothing todo.
1534      } else if (DL == LastDL) {
1535        // Just repeat the same debug loc as last time.
1536        Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC_AGAIN, Vals);
1537      } else {
1538        MDNode *Scope, *IA;
1539        DL.getScopeAndInlinedAt(Scope, IA, I->getContext());
1540        assert(Scope && "Expected valid scope");
1541
1542        Vals.push_back(DL.getLine());
1543        Vals.push_back(DL.getCol());
1544        Vals.push_back(VE.getMetadataOrNullID(Scope));
1545        Vals.push_back(VE.getMetadataOrNullID(IA));
1546        Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC, Vals);
1547        Vals.clear();
1548
1549        LastDL = DL;
1550      }
1551    }
1552
1553  // Emit names for all the instructions etc.
1554  WriteValueSymbolTable(F.getValueSymbolTable(), VE, Stream);
1555
1556  if (NeedsMetadataAttachment)
1557    WriteMetadataAttachment(F, VE, Stream);
1558  if (shouldPreserveBitcodeUseListOrder())
1559    WriteUseListBlock(&F, VE, Stream);
1560  VE.purgeFunction();
1561  Stream.ExitBlock();
1562}
1563
1564// Emit blockinfo, which defines the standard abbreviations etc.
1565static void WriteBlockInfo(const llvm_3_2::ValueEnumerator &VE,
1566                           BitstreamWriter &Stream) {
1567  // We only want to emit block info records for blocks that have multiple
1568  // instances: CONSTANTS_BLOCK, FUNCTION_BLOCK and VALUE_SYMTAB_BLOCK.  Other
1569  // blocks can defined their abbrevs inline.
1570  Stream.EnterBlockInfoBlock(2);
1571
1572  { // 8-bit fixed-width VST_ENTRY/VST_BBENTRY strings.
1573    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1574    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3));
1575    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1576    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1577    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
1578    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1579                                   Abbv) != VST_ENTRY_8_ABBREV)
1580      llvm_unreachable("Unexpected abbrev ordering!");
1581  }
1582
1583  { // 7-bit fixed width VST_ENTRY strings.
1584    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1585    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1586    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1587    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1588    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
1589    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1590                                   Abbv) != VST_ENTRY_7_ABBREV)
1591      llvm_unreachable("Unexpected abbrev ordering!");
1592  }
1593  { // 6-bit char6 VST_ENTRY strings.
1594    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1595    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1596    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1597    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1598    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1599    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1600                                   Abbv) != VST_ENTRY_6_ABBREV)
1601      llvm_unreachable("Unexpected abbrev ordering!");
1602  }
1603  { // 6-bit char6 VST_BBENTRY strings.
1604    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1605    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_BBENTRY));
1606    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1607    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1608    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1609    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1610                                   Abbv) != VST_BBENTRY_6_ABBREV)
1611      llvm_unreachable("Unexpected abbrev ordering!");
1612  }
1613
1614
1615
1616  { // SETTYPE abbrev for CONSTANTS_BLOCK.
1617    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1618    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_SETTYPE));
1619    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1620                              Log2_32_Ceil(VE.getTypes().size()+1)));
1621    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1622                                   Abbv) != CONSTANTS_SETTYPE_ABBREV)
1623      llvm_unreachable("Unexpected abbrev ordering!");
1624  }
1625
1626  { // INTEGER abbrev for CONSTANTS_BLOCK.
1627    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1628    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_INTEGER));
1629    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1630    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1631                                   Abbv) != CONSTANTS_INTEGER_ABBREV)
1632      llvm_unreachable("Unexpected abbrev ordering!");
1633  }
1634
1635  { // CE_CAST abbrev for CONSTANTS_BLOCK.
1636    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1637    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CE_CAST));
1638    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // cast opc
1639    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // typeid
1640                              Log2_32_Ceil(VE.getTypes().size()+1)));
1641    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));    // value id
1642
1643    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1644                                   Abbv) != CONSTANTS_CE_CAST_Abbrev)
1645      llvm_unreachable("Unexpected abbrev ordering!");
1646  }
1647  { // NULL abbrev for CONSTANTS_BLOCK.
1648    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1649    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_NULL));
1650    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1651                                   Abbv) != CONSTANTS_NULL_Abbrev)
1652      llvm_unreachable("Unexpected abbrev ordering!");
1653  }
1654
1655  // FIXME: This should only use space for first class types!
1656
1657  { // INST_LOAD abbrev for FUNCTION_BLOCK.
1658    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1659    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_LOAD));
1660    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Ptr
1661    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4)); // Align
1662    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // volatile
1663    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1664                                   Abbv) != FUNCTION_INST_LOAD_ABBREV)
1665      llvm_unreachable("Unexpected abbrev ordering!");
1666  }
1667  { // INST_BINOP abbrev for FUNCTION_BLOCK.
1668    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1669    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1670    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1671    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1672    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1673    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1674                                   Abbv) != FUNCTION_INST_BINOP_ABBREV)
1675      llvm_unreachable("Unexpected abbrev ordering!");
1676  }
1677  { // INST_BINOP_FLAGS abbrev for FUNCTION_BLOCK.
1678    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1679    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1680    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1681    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1682    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1683    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7)); // flags
1684    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1685                                   Abbv) != FUNCTION_INST_BINOP_FLAGS_ABBREV)
1686      llvm_unreachable("Unexpected abbrev ordering!");
1687  }
1688  { // INST_CAST abbrev for FUNCTION_BLOCK.
1689    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1690    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_CAST));
1691    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));    // OpVal
1692    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // dest ty
1693                              Log2_32_Ceil(VE.getTypes().size()+1)));
1694    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // opc
1695    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1696                                   Abbv) != FUNCTION_INST_CAST_ABBREV)
1697      llvm_unreachable("Unexpected abbrev ordering!");
1698  }
1699
1700  { // INST_RET abbrev for FUNCTION_BLOCK.
1701    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1702    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1703    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1704                                   Abbv) != FUNCTION_INST_RET_VOID_ABBREV)
1705      llvm_unreachable("Unexpected abbrev ordering!");
1706  }
1707  { // INST_RET abbrev for FUNCTION_BLOCK.
1708    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1709    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1710    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ValID
1711    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1712                                   Abbv) != FUNCTION_INST_RET_VAL_ABBREV)
1713      llvm_unreachable("Unexpected abbrev ordering!");
1714  }
1715  { // INST_UNREACHABLE abbrev for FUNCTION_BLOCK.
1716    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1717    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_UNREACHABLE));
1718    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1719                                   Abbv) != FUNCTION_INST_UNREACHABLE_ABBREV)
1720      llvm_unreachable("Unexpected abbrev ordering!");
1721  }
1722
1723  Stream.ExitBlock();
1724}
1725
1726/// WriteModule - Emit the specified module to the bitstream.
1727static void WriteModule(const Module *M, BitstreamWriter &Stream) {
1728  Stream.EnterSubblock(bitc::MODULE_BLOCK_ID, 3);
1729
1730  SmallVector<unsigned, 1> Vals;
1731  // TODO(srhines): RenderScript is always version 0 for now.
1732  unsigned CurVersion = 0;
1733  if (CurVersion) {
1734    Vals.push_back(CurVersion);
1735    Stream.EmitRecord(bitc::MODULE_CODE_VERSION, Vals);
1736  }
1737
1738  // Analyze the module, enumerating globals, functions, etc.
1739  llvm_3_2::ValueEnumerator VE(*M);
1740
1741  // Emit blockinfo, which defines the standard abbreviations etc.
1742  WriteBlockInfo(VE, Stream);
1743
1744  // Emit information about parameter attributes.
1745  WriteAttributeTable(VE, Stream);
1746
1747  // Emit information describing all of the types in the module.
1748  WriteTypeTable(VE, Stream);
1749
1750  // Emit top-level description of module, including target triple, inline asm,
1751  // descriptors for global variables, and function prototype info.
1752  WriteModuleInfo(M, VE, Stream);
1753
1754  // Emit constants.
1755  WriteModuleConstants(VE, Stream);
1756
1757  // Emit metadata.
1758  WriteModuleMetadata(M, VE, Stream);
1759
1760  // Emit metadata.
1761  WriteModuleMetadataStore(M, Stream);
1762
1763  // Emit names for globals/functions etc.
1764  WriteValueSymbolTable(M->getValueSymbolTable(), VE, Stream);
1765
1766  // Emit module-level use-lists.
1767  if (shouldPreserveBitcodeUseListOrder())
1768    WriteUseListBlock(nullptr, VE, Stream);
1769
1770  // Emit function bodies.
1771  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F)
1772    if (!F->isDeclaration())
1773      WriteFunction(*F, VE, Stream);
1774
1775  Stream.ExitBlock();
1776}
1777
1778/// EmitDarwinBCHeader - If generating a bc file on darwin, we have to emit a
1779/// header and trailer to make it compatible with the system archiver.  To do
1780/// this we emit the following header, and then emit a trailer that pads the
1781/// file out to be a multiple of 16 bytes.
1782///
1783/// struct bc_header {
1784///   uint32_t Magic;         // 0x0B17C0DE
1785///   uint32_t Version;       // Version, currently always 0.
1786///   uint32_t BitcodeOffset; // Offset to traditional bitcode file.
1787///   uint32_t BitcodeSize;   // Size of traditional bitcode file.
1788///   uint32_t CPUType;       // CPU specifier.
1789///   ... potentially more later ...
1790/// };
1791enum {
1792  DarwinBCSizeFieldOffset = 3*4, // Offset to bitcode_size.
1793  DarwinBCHeaderSize = 5*4
1794};
1795
1796static void WriteInt32ToBuffer(uint32_t Value, SmallVectorImpl<char> &Buffer,
1797                               uint32_t &Position) {
1798  Buffer[Position + 0] = (unsigned char) (Value >>  0);
1799  Buffer[Position + 1] = (unsigned char) (Value >>  8);
1800  Buffer[Position + 2] = (unsigned char) (Value >> 16);
1801  Buffer[Position + 3] = (unsigned char) (Value >> 24);
1802  Position += 4;
1803}
1804
1805static void EmitDarwinBCHeaderAndTrailer(SmallVectorImpl<char> &Buffer,
1806                                         const Triple &TT) {
1807  unsigned CPUType = ~0U;
1808
1809  // Match x86_64-*, i[3-9]86-*, powerpc-*, powerpc64-*, arm-*, thumb-*,
1810  // armv[0-9]-*, thumbv[0-9]-*, armv5te-*, or armv6t2-*. The CPUType is a magic
1811  // number from /usr/include/mach/machine.h.  It is ok to reproduce the
1812  // specific constants here because they are implicitly part of the Darwin ABI.
1813  enum {
1814    DARWIN_CPU_ARCH_ABI64      = 0x01000000,
1815    DARWIN_CPU_TYPE_X86        = 7,
1816    DARWIN_CPU_TYPE_ARM        = 12,
1817    DARWIN_CPU_TYPE_POWERPC    = 18
1818  };
1819
1820  Triple::ArchType Arch = TT.getArch();
1821  if (Arch == Triple::x86_64)
1822    CPUType = DARWIN_CPU_TYPE_X86 | DARWIN_CPU_ARCH_ABI64;
1823  else if (Arch == Triple::x86)
1824    CPUType = DARWIN_CPU_TYPE_X86;
1825  else if (Arch == Triple::ppc)
1826    CPUType = DARWIN_CPU_TYPE_POWERPC;
1827  else if (Arch == Triple::ppc64)
1828    CPUType = DARWIN_CPU_TYPE_POWERPC | DARWIN_CPU_ARCH_ABI64;
1829  else if (Arch == Triple::arm || Arch == Triple::thumb)
1830    CPUType = DARWIN_CPU_TYPE_ARM;
1831
1832  // Traditional Bitcode starts after header.
1833  assert(Buffer.size() >= DarwinBCHeaderSize &&
1834         "Expected header size to be reserved");
1835  unsigned BCOffset = DarwinBCHeaderSize;
1836  unsigned BCSize = Buffer.size()-DarwinBCHeaderSize;
1837
1838  // Write the magic and version.
1839  unsigned Position = 0;
1840  WriteInt32ToBuffer(0x0B17C0DE , Buffer, Position);
1841  WriteInt32ToBuffer(0          , Buffer, Position); // Version.
1842  WriteInt32ToBuffer(BCOffset   , Buffer, Position);
1843  WriteInt32ToBuffer(BCSize     , Buffer, Position);
1844  WriteInt32ToBuffer(CPUType    , Buffer, Position);
1845
1846  // If the file is not a multiple of 16 bytes, insert dummy padding.
1847  while (Buffer.size() & 15)
1848    Buffer.push_back(0);
1849}
1850
1851/// WriteBitcodeToFile - Write the specified module to the specified output
1852/// stream.
1853void llvm_3_2::WriteBitcodeToFile(const Module *M, raw_ostream &Out) {
1854  SmallVector<char, 0> Buffer;
1855  Buffer.reserve(256*1024);
1856
1857  // If this is darwin or another generic macho target, reserve space for the
1858  // header.
1859  Triple TT(M->getTargetTriple());
1860  if (TT.isOSDarwin())
1861    Buffer.insert(Buffer.begin(), DarwinBCHeaderSize, 0);
1862
1863  // Emit the module into the buffer.
1864  {
1865    BitstreamWriter Stream(Buffer);
1866
1867    // Emit the file header.
1868    Stream.Emit((unsigned)'B', 8);
1869    Stream.Emit((unsigned)'C', 8);
1870    Stream.Emit(0x0, 4);
1871    Stream.Emit(0xC, 4);
1872    Stream.Emit(0xE, 4);
1873    Stream.Emit(0xD, 4);
1874
1875    // Emit the module.
1876    WriteModule(M, Stream);
1877  }
1878
1879  if (TT.isOSDarwin())
1880    EmitDarwinBCHeaderAndTrailer(Buffer, TT);
1881
1882  // Write the generated bitstream to "Out".
1883  Out.write((char*)&Buffer.front(), Buffer.size());
1884}
1885