BitcodeReader.cpp revision 320fc8a39e17f5725f5711248e06bcb36f122687 
1//===- BitcodeReader.cpp - Internal BitcodeReader implementation ----------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file was developed by Chris Lattner and is distributed under
6// the University of Illinois Open Source License.  See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This header defines the BitcodeReader class.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/Bitcode/ReaderWriter.h"
15#include "BitcodeReader.h"
16#include "llvm/Constants.h"
17#include "llvm/DerivedTypes.h"
18#include "llvm/InlineAsm.h"
19#include "llvm/Instructions.h"
20#include "llvm/Module.h"
21#include "llvm/ParameterAttributes.h"
22#include "llvm/ADT/SmallString.h"
23#include "llvm/Support/MathExtras.h"
24#include "llvm/Support/MemoryBuffer.h"
25using namespace llvm;
26
27void BitcodeReader::FreeState() {
28  delete Buffer;
29  Buffer = 0;
30  std::vector<PATypeHolder>().swap(TypeList);
31  ValueList.clear();
32  std::vector<const ParamAttrsList*>().swap(ParamAttrs);
33  std::vector<BasicBlock*>().swap(FunctionBBs);
34  std::vector<Function*>().swap(FunctionsWithBodies);
35  DeferredFunctionInfo.clear();
36}
37
38//===----------------------------------------------------------------------===//
39//  Helper functions to implement forward reference resolution, etc.
40//===----------------------------------------------------------------------===//
41
42/// ConvertToString - Convert a string from a record into an std::string, return
43/// true on failure.
44template<typename StrTy>
45static bool ConvertToString(SmallVector<uint64_t, 64> &Record, unsigned Idx,
46                            StrTy &Result) {
47  if (Idx > Record.size())
48    return true;
49
50  for (unsigned i = Idx, e = Record.size(); i != e; ++i)
51    Result += (char)Record[i];
52  return false;
53}
54
55static GlobalValue::LinkageTypes GetDecodedLinkage(unsigned Val) {
56  switch (Val) {
57  default: // Map unknown/new linkages to external
58  case 0: return GlobalValue::ExternalLinkage;
59  case 1: return GlobalValue::WeakLinkage;
60  case 2: return GlobalValue::AppendingLinkage;
61  case 3: return GlobalValue::InternalLinkage;
62  case 4: return GlobalValue::LinkOnceLinkage;
63  case 5: return GlobalValue::DLLImportLinkage;
64  case 6: return GlobalValue::DLLExportLinkage;
65  case 7: return GlobalValue::ExternalWeakLinkage;
66  }
67}
68
69static GlobalValue::VisibilityTypes GetDecodedVisibility(unsigned Val) {
70  switch (Val) {
71  default: // Map unknown visibilities to default.
72  case 0: return GlobalValue::DefaultVisibility;
73  case 1: return GlobalValue::HiddenVisibility;
74  case 2: return GlobalValue::ProtectedVisibility;
75  }
76}
77
78static int GetDecodedCastOpcode(unsigned Val) {
79  switch (Val) {
80  default: return -1;
81  case bitc::CAST_TRUNC   : return Instruction::Trunc;
82  case bitc::CAST_ZEXT    : return Instruction::ZExt;
83  case bitc::CAST_SEXT    : return Instruction::SExt;
84  case bitc::CAST_FPTOUI  : return Instruction::FPToUI;
85  case bitc::CAST_FPTOSI  : return Instruction::FPToSI;
86  case bitc::CAST_UITOFP  : return Instruction::UIToFP;
87  case bitc::CAST_SITOFP  : return Instruction::SIToFP;
88  case bitc::CAST_FPTRUNC : return Instruction::FPTrunc;
89  case bitc::CAST_FPEXT   : return Instruction::FPExt;
90  case bitc::CAST_PTRTOINT: return Instruction::PtrToInt;
91  case bitc::CAST_INTTOPTR: return Instruction::IntToPtr;
92  case bitc::CAST_BITCAST : return Instruction::BitCast;
93  }
94}
95static int GetDecodedBinaryOpcode(unsigned Val, const Type *Ty) {
96  switch (Val) {
97  default: return -1;
98  case bitc::BINOP_ADD:  return Instruction::Add;
99  case bitc::BINOP_SUB:  return Instruction::Sub;
100  case bitc::BINOP_MUL:  return Instruction::Mul;
101  case bitc::BINOP_UDIV: return Instruction::UDiv;
102  case bitc::BINOP_SDIV:
103    return Ty->isFPOrFPVector() ? Instruction::FDiv : Instruction::SDiv;
104  case bitc::BINOP_UREM: return Instruction::URem;
105  case bitc::BINOP_SREM:
106    return Ty->isFPOrFPVector() ? Instruction::FRem : Instruction::SRem;
107  case bitc::BINOP_SHL:  return Instruction::Shl;
108  case bitc::BINOP_LSHR: return Instruction::LShr;
109  case bitc::BINOP_ASHR: return Instruction::AShr;
110  case bitc::BINOP_AND:  return Instruction::And;
111  case bitc::BINOP_OR:   return Instruction::Or;
112  case bitc::BINOP_XOR:  return Instruction::Xor;
113  }
114}
115
116
117namespace {
118  /// @brief A class for maintaining the slot number definition
119  /// as a placeholder for the actual definition for forward constants defs.
120  class ConstantPlaceHolder : public ConstantExpr {
121    ConstantPlaceHolder();                       // DO NOT IMPLEMENT
122    void operator=(const ConstantPlaceHolder &); // DO NOT IMPLEMENT
123  public:
124    Use Op;
125    ConstantPlaceHolder(const Type *Ty)
126      : ConstantExpr(Ty, Instruction::UserOp1, &Op, 1),
127        Op(UndefValue::get(Type::Int32Ty), this) {
128    }
129  };
130}
131
132Constant *BitcodeReaderValueList::getConstantFwdRef(unsigned Idx,
133                                                    const Type *Ty) {
134  if (Idx >= size()) {
135    // Insert a bunch of null values.
136    Uses.resize(Idx+1);
137    OperandList = &Uses[0];
138    NumOperands = Idx+1;
139  }
140
141  if (Value *V = Uses[Idx]) {
142    assert(Ty == V->getType() && "Type mismatch in constant table!");
143    return cast<Constant>(V);
144  }
145
146  // Create and return a placeholder, which will later be RAUW'd.
147  Constant *C = new ConstantPlaceHolder(Ty);
148  Uses[Idx].init(C, this);
149  return C;
150}
151
152Value *BitcodeReaderValueList::getValueFwdRef(unsigned Idx, const Type *Ty) {
153  if (Idx >= size()) {
154    // Insert a bunch of null values.
155    Uses.resize(Idx+1);
156    OperandList = &Uses[0];
157    NumOperands = Idx+1;
158  }
159
160  if (Value *V = Uses[Idx]) {
161    assert((Ty == 0 || Ty == V->getType()) && "Type mismatch in value table!");
162    return V;
163  }
164
165  // No type specified, must be invalid reference.
166  if (Ty == 0) return 0;
167
168  // Create and return a placeholder, which will later be RAUW'd.
169  Value *V = new Argument(Ty);
170  Uses[Idx].init(V, this);
171  return V;
172}
173
174
175const Type *BitcodeReader::getTypeByID(unsigned ID, bool isTypeTable) {
176  // If the TypeID is in range, return it.
177  if (ID < TypeList.size())
178    return TypeList[ID].get();
179  if (!isTypeTable) return 0;
180
181  // The type table allows forward references.  Push as many Opaque types as
182  // needed to get up to ID.
183  while (TypeList.size() <= ID)
184    TypeList.push_back(OpaqueType::get());
185  return TypeList.back().get();
186}
187
188//===----------------------------------------------------------------------===//
189//  Functions for parsing blocks from the bitcode file
190//===----------------------------------------------------------------------===//
191
192bool BitcodeReader::ParseParamAttrBlock() {
193  if (Stream.EnterSubBlock(bitc::PARAMATTR_BLOCK_ID))
194    return Error("Malformed block record");
195
196  if (!ParamAttrs.empty())
197    return Error("Multiple PARAMATTR blocks found!");
198
199  SmallVector<uint64_t, 64> Record;
200
201  ParamAttrsVector Attrs;
202
203  // Read all the records.
204  while (1) {
205    unsigned Code = Stream.ReadCode();
206    if (Code == bitc::END_BLOCK) {
207      if (Stream.ReadBlockEnd())
208        return Error("Error at end of PARAMATTR block");
209      return false;
210    }
211
212    if (Code == bitc::ENTER_SUBBLOCK) {
213      // No known subblocks, always skip them.
214      Stream.ReadSubBlockID();
215      if (Stream.SkipBlock())
216        return Error("Malformed block record");
217      continue;
218    }
219
220    if (Code == bitc::DEFINE_ABBREV) {
221      Stream.ReadAbbrevRecord();
222      continue;
223    }
224
225    // Read a record.
226    Record.clear();
227    switch (Stream.ReadRecord(Code, Record)) {
228    default:  // Default behavior: ignore.
229      break;
230    case bitc::PARAMATTR_CODE_ENTRY: { // ENTRY: [paramidx0, attr0, ...]
231      if (Record.size() & 1)
232        return Error("Invalid ENTRY record");
233
234      ParamAttrsWithIndex PAWI;
235      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
236        PAWI.index = Record[i];
237        PAWI.attrs = Record[i+1];
238        Attrs.push_back(PAWI);
239      }
240      ParamAttrs.push_back(ParamAttrsList::get(Attrs));
241      Attrs.clear();
242      break;
243    }
244    }
245  }
246}
247
248
249bool BitcodeReader::ParseTypeTable() {
250  if (Stream.EnterSubBlock(bitc::TYPE_BLOCK_ID))
251    return Error("Malformed block record");
252
253  if (!TypeList.empty())
254    return Error("Multiple TYPE_BLOCKs found!");
255
256  SmallVector<uint64_t, 64> Record;
257  unsigned NumRecords = 0;
258
259  // Read all the records for this type table.
260  while (1) {
261    unsigned Code = Stream.ReadCode();
262    if (Code == bitc::END_BLOCK) {
263      if (NumRecords != TypeList.size())
264        return Error("Invalid type forward reference in TYPE_BLOCK");
265      if (Stream.ReadBlockEnd())
266        return Error("Error at end of type table block");
267      return false;
268    }
269
270    if (Code == bitc::ENTER_SUBBLOCK) {
271      // No known subblocks, always skip them.
272      Stream.ReadSubBlockID();
273      if (Stream.SkipBlock())
274        return Error("Malformed block record");
275      continue;
276    }
277
278    if (Code == bitc::DEFINE_ABBREV) {
279      Stream.ReadAbbrevRecord();
280      continue;
281    }
282
283    // Read a record.
284    Record.clear();
285    const Type *ResultTy = 0;
286    switch (Stream.ReadRecord(Code, Record)) {
287    default:  // Default behavior: unknown type.
288      ResultTy = 0;
289      break;
290    case bitc::TYPE_CODE_NUMENTRY: // TYPE_CODE_NUMENTRY: [numentries]
291      // TYPE_CODE_NUMENTRY contains a count of the number of types in the
292      // type list.  This allows us to reserve space.
293      if (Record.size() < 1)
294        return Error("Invalid TYPE_CODE_NUMENTRY record");
295      TypeList.reserve(Record[0]);
296      continue;
297    case bitc::TYPE_CODE_VOID:      // VOID
298      ResultTy = Type::VoidTy;
299      break;
300    case bitc::TYPE_CODE_FLOAT:     // FLOAT
301      ResultTy = Type::FloatTy;
302      break;
303    case bitc::TYPE_CODE_DOUBLE:    // DOUBLE
304      ResultTy = Type::DoubleTy;
305      break;
306    case bitc::TYPE_CODE_X86_FP80:  // X86_FP80
307      ResultTy = Type::X86_FP80Ty;
308      break;
309    case bitc::TYPE_CODE_FP128:     // FP128
310      ResultTy = Type::FP128Ty;
311      break;
312    case bitc::TYPE_CODE_PPC_FP128: // PPC_FP128
313      ResultTy = Type::PPC_FP128Ty;
314      break;
315    case bitc::TYPE_CODE_LABEL:     // LABEL
316      ResultTy = Type::LabelTy;
317      break;
318    case bitc::TYPE_CODE_OPAQUE:    // OPAQUE
319      ResultTy = 0;
320      break;
321    case bitc::TYPE_CODE_INTEGER:   // INTEGER: [width]
322      if (Record.size() < 1)
323        return Error("Invalid Integer type record");
324
325      ResultTy = IntegerType::get(Record[0]);
326      break;
327    case bitc::TYPE_CODE_POINTER:   // POINTER: [pointee type]
328      if (Record.size() < 1)
329        return Error("Invalid POINTER type record");
330      ResultTy = PointerType::get(getTypeByID(Record[0], true));
331      break;
332    case bitc::TYPE_CODE_FUNCTION: {
333      // FUNCTION: [vararg, attrid, retty, paramty x N]
334      if (Record.size() < 3)
335        return Error("Invalid FUNCTION type record");
336      std::vector<const Type*> ArgTys;
337      for (unsigned i = 3, e = Record.size(); i != e; ++i)
338        ArgTys.push_back(getTypeByID(Record[i], true));
339
340      ResultTy = FunctionType::get(getTypeByID(Record[2], true), ArgTys,
341                                   Record[0], getParamAttrs(Record[1]));
342      break;
343    }
344    case bitc::TYPE_CODE_STRUCT: {  // STRUCT: [ispacked, eltty x N]
345      if (Record.size() < 1)
346        return Error("Invalid STRUCT type record");
347      std::vector<const Type*> EltTys;
348      for (unsigned i = 1, e = Record.size(); i != e; ++i)
349        EltTys.push_back(getTypeByID(Record[i], true));
350      ResultTy = StructType::get(EltTys, Record[0]);
351      break;
352    }
353    case bitc::TYPE_CODE_ARRAY:     // ARRAY: [numelts, eltty]
354      if (Record.size() < 2)
355        return Error("Invalid ARRAY type record");
356      ResultTy = ArrayType::get(getTypeByID(Record[1], true), Record[0]);
357      break;
358    case bitc::TYPE_CODE_VECTOR:    // VECTOR: [numelts, eltty]
359      if (Record.size() < 2)
360        return Error("Invalid VECTOR type record");
361      ResultTy = VectorType::get(getTypeByID(Record[1], true), Record[0]);
362      break;
363    }
364
365    if (NumRecords == TypeList.size()) {
366      // If this is a new type slot, just append it.
367      TypeList.push_back(ResultTy ? ResultTy : OpaqueType::get());
368      ++NumRecords;
369    } else if (ResultTy == 0) {
370      // Otherwise, this was forward referenced, so an opaque type was created,
371      // but the result type is actually just an opaque.  Leave the one we
372      // created previously.
373      ++NumRecords;
374    } else {
375      // Otherwise, this was forward referenced, so an opaque type was created.
376      // Resolve the opaque type to the real type now.
377      assert(NumRecords < TypeList.size() && "Typelist imbalance");
378      const OpaqueType *OldTy = cast<OpaqueType>(TypeList[NumRecords++].get());
379
380      // Don't directly push the new type on the Tab. Instead we want to replace
381      // the opaque type we previously inserted with the new concrete value. The
382      // refinement from the abstract (opaque) type to the new type causes all
383      // uses of the abstract type to use the concrete type (NewTy). This will
384      // also cause the opaque type to be deleted.
385      const_cast<OpaqueType*>(OldTy)->refineAbstractTypeTo(ResultTy);
386
387      // This should have replaced the old opaque type with the new type in the
388      // value table... or with a preexisting type that was already in the
389      // system.  Let's just make sure it did.
390      assert(TypeList[NumRecords-1].get() != OldTy &&
391             "refineAbstractType didn't work!");
392    }
393  }
394}
395
396
397bool BitcodeReader::ParseTypeSymbolTable() {
398  if (Stream.EnterSubBlock(bitc::TYPE_SYMTAB_BLOCK_ID))
399    return Error("Malformed block record");
400
401  SmallVector<uint64_t, 64> Record;
402
403  // Read all the records for this type table.
404  std::string TypeName;
405  while (1) {
406    unsigned Code = Stream.ReadCode();
407    if (Code == bitc::END_BLOCK) {
408      if (Stream.ReadBlockEnd())
409        return Error("Error at end of type symbol table block");
410      return false;
411    }
412
413    if (Code == bitc::ENTER_SUBBLOCK) {
414      // No known subblocks, always skip them.
415      Stream.ReadSubBlockID();
416      if (Stream.SkipBlock())
417        return Error("Malformed block record");
418      continue;
419    }
420
421    if (Code == bitc::DEFINE_ABBREV) {
422      Stream.ReadAbbrevRecord();
423      continue;
424    }
425
426    // Read a record.
427    Record.clear();
428    switch (Stream.ReadRecord(Code, Record)) {
429    default:  // Default behavior: unknown type.
430      break;
431    case bitc::TST_CODE_ENTRY:    // TST_ENTRY: [typeid, namechar x N]
432      if (ConvertToString(Record, 1, TypeName))
433        return Error("Invalid TST_ENTRY record");
434      unsigned TypeID = Record[0];
435      if (TypeID >= TypeList.size())
436        return Error("Invalid Type ID in TST_ENTRY record");
437
438      TheModule->addTypeName(TypeName, TypeList[TypeID].get());
439      TypeName.clear();
440      break;
441    }
442  }
443}
444
445bool BitcodeReader::ParseValueSymbolTable() {
446  if (Stream.EnterSubBlock(bitc::VALUE_SYMTAB_BLOCK_ID))
447    return Error("Malformed block record");
448
449  SmallVector<uint64_t, 64> Record;
450
451  // Read all the records for this value table.
452  SmallString<128> ValueName;
453  while (1) {
454    unsigned Code = Stream.ReadCode();
455    if (Code == bitc::END_BLOCK) {
456      if (Stream.ReadBlockEnd())
457        return Error("Error at end of value symbol table block");
458      return false;
459    }
460    if (Code == bitc::ENTER_SUBBLOCK) {
461      // No known subblocks, always skip them.
462      Stream.ReadSubBlockID();
463      if (Stream.SkipBlock())
464        return Error("Malformed block record");
465      continue;
466    }
467
468    if (Code == bitc::DEFINE_ABBREV) {
469      Stream.ReadAbbrevRecord();
470      continue;
471    }
472
473    // Read a record.
474    Record.clear();
475    switch (Stream.ReadRecord(Code, Record)) {
476    default:  // Default behavior: unknown type.
477      break;
478    case bitc::VST_CODE_ENTRY: {  // VST_ENTRY: [valueid, namechar x N]
479      if (ConvertToString(Record, 1, ValueName))
480        return Error("Invalid TST_ENTRY record");
481      unsigned ValueID = Record[0];
482      if (ValueID >= ValueList.size())
483        return Error("Invalid Value ID in VST_ENTRY record");
484      Value *V = ValueList[ValueID];
485
486      V->setName(&ValueName[0], ValueName.size());
487      ValueName.clear();
488      break;
489    }
490    case bitc::VST_CODE_BBENTRY: {
491      if (ConvertToString(Record, 1, ValueName))
492        return Error("Invalid VST_BBENTRY record");
493      BasicBlock *BB = getBasicBlock(Record[0]);
494      if (BB == 0)
495        return Error("Invalid BB ID in VST_BBENTRY record");
496
497      BB->setName(&ValueName[0], ValueName.size());
498      ValueName.clear();
499      break;
500    }
501    }
502  }
503}
504
505/// DecodeSignRotatedValue - Decode a signed value stored with the sign bit in
506/// the LSB for dense VBR encoding.
507static uint64_t DecodeSignRotatedValue(uint64_t V) {
508  if ((V & 1) == 0)
509    return V >> 1;
510  if (V != 1)
511    return -(V >> 1);
512  // There is no such thing as -0 with integers.  "-0" really means MININT.
513  return 1ULL << 63;
514}
515
516/// ResolveGlobalAndAliasInits - Resolve all of the initializers for global
517/// values and aliases that we can.
518bool BitcodeReader::ResolveGlobalAndAliasInits() {
519  std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInitWorklist;
520  std::vector<std::pair<GlobalAlias*, unsigned> > AliasInitWorklist;
521
522  GlobalInitWorklist.swap(GlobalInits);
523  AliasInitWorklist.swap(AliasInits);
524
525  while (!GlobalInitWorklist.empty()) {
526    unsigned ValID = GlobalInitWorklist.back().second;
527    if (ValID >= ValueList.size()) {
528      // Not ready to resolve this yet, it requires something later in the file.
529      GlobalInits.push_back(GlobalInitWorklist.back());
530    } else {
531      if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
532        GlobalInitWorklist.back().first->setInitializer(C);
533      else
534        return Error("Global variable initializer is not a constant!");
535    }
536    GlobalInitWorklist.pop_back();
537  }
538
539  while (!AliasInitWorklist.empty()) {
540    unsigned ValID = AliasInitWorklist.back().second;
541    if (ValID >= ValueList.size()) {
542      AliasInits.push_back(AliasInitWorklist.back());
543    } else {
544      if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
545        AliasInitWorklist.back().first->setAliasee(C);
546      else
547        return Error("Alias initializer is not a constant!");
548    }
549    AliasInitWorklist.pop_back();
550  }
551  return false;
552}
553
554
555bool BitcodeReader::ParseConstants() {
556  if (Stream.EnterSubBlock(bitc::CONSTANTS_BLOCK_ID))
557    return Error("Malformed block record");
558
559  SmallVector<uint64_t, 64> Record;
560
561  // Read all the records for this value table.
562  const Type *CurTy = Type::Int32Ty;
563  unsigned NextCstNo = ValueList.size();
564  while (1) {
565    unsigned Code = Stream.ReadCode();
566    if (Code == bitc::END_BLOCK) {
567      if (NextCstNo != ValueList.size())
568        return Error("Invalid constant reference!");
569
570      if (Stream.ReadBlockEnd())
571        return Error("Error at end of constants block");
572      return false;
573    }
574
575    if (Code == bitc::ENTER_SUBBLOCK) {
576      // No known subblocks, always skip them.
577      Stream.ReadSubBlockID();
578      if (Stream.SkipBlock())
579        return Error("Malformed block record");
580      continue;
581    }
582
583    if (Code == bitc::DEFINE_ABBREV) {
584      Stream.ReadAbbrevRecord();
585      continue;
586    }
587
588    // Read a record.
589    Record.clear();
590    Value *V = 0;
591    switch (Stream.ReadRecord(Code, Record)) {
592    default:  // Default behavior: unknown constant
593    case bitc::CST_CODE_UNDEF:     // UNDEF
594      V = UndefValue::get(CurTy);
595      break;
596    case bitc::CST_CODE_SETTYPE:   // SETTYPE: [typeid]
597      if (Record.empty())
598        return Error("Malformed CST_SETTYPE record");
599      if (Record[0] >= TypeList.size())
600        return Error("Invalid Type ID in CST_SETTYPE record");
601      CurTy = TypeList[Record[0]];
602      continue;  // Skip the ValueList manipulation.
603    case bitc::CST_CODE_NULL:      // NULL
604      V = Constant::getNullValue(CurTy);
605      break;
606    case bitc::CST_CODE_INTEGER:   // INTEGER: [intval]
607      if (!isa<IntegerType>(CurTy) || Record.empty())
608        return Error("Invalid CST_INTEGER record");
609      V = ConstantInt::get(CurTy, DecodeSignRotatedValue(Record[0]));
610      break;
611    case bitc::CST_CODE_WIDE_INTEGER: {// WIDE_INTEGER: [n x intval]
612      if (!isa<IntegerType>(CurTy) || Record.empty())
613        return Error("Invalid WIDE_INTEGER record");
614
615      unsigned NumWords = Record.size();
616      SmallVector<uint64_t, 8> Words;
617      Words.resize(NumWords);
618      for (unsigned i = 0; i != NumWords; ++i)
619        Words[i] = DecodeSignRotatedValue(Record[i]);
620      V = ConstantInt::get(APInt(cast<IntegerType>(CurTy)->getBitWidth(),
621                                 NumWords, &Words[0]));
622      break;
623    }
624    case bitc::CST_CODE_FLOAT:     // FLOAT: [fpval]
625      if (Record.empty())
626        return Error("Invalid FLOAT record");
627      if (CurTy == Type::FloatTy)
628        V = ConstantFP::get(CurTy, BitsToFloat(Record[0]));
629      else if (CurTy == Type::DoubleTy)
630        V = ConstantFP::get(CurTy, BitsToDouble(Record[0]));
631      else
632        V = UndefValue::get(CurTy);
633      break;
634
635    case bitc::CST_CODE_AGGREGATE: {// AGGREGATE: [n x value number]
636      if (Record.empty())
637        return Error("Invalid CST_AGGREGATE record");
638
639      unsigned Size = Record.size();
640      std::vector<Constant*> Elts;
641
642      if (const StructType *STy = dyn_cast<StructType>(CurTy)) {
643        for (unsigned i = 0; i != Size; ++i)
644          Elts.push_back(ValueList.getConstantFwdRef(Record[i],
645                                                     STy->getElementType(i)));
646        V = ConstantStruct::get(STy, Elts);
647      } else if (const ArrayType *ATy = dyn_cast<ArrayType>(CurTy)) {
648        const Type *EltTy = ATy->getElementType();
649        for (unsigned i = 0; i != Size; ++i)
650          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
651        V = ConstantArray::get(ATy, Elts);
652      } else if (const VectorType *VTy = dyn_cast<VectorType>(CurTy)) {
653        const Type *EltTy = VTy->getElementType();
654        for (unsigned i = 0; i != Size; ++i)
655          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
656        V = ConstantVector::get(Elts);
657      } else {
658        V = UndefValue::get(CurTy);
659      }
660      break;
661    }
662    case bitc::CST_CODE_STRING: { // STRING: [values]
663      if (Record.empty())
664        return Error("Invalid CST_AGGREGATE record");
665
666      const ArrayType *ATy = cast<ArrayType>(CurTy);
667      const Type *EltTy = ATy->getElementType();
668
669      unsigned Size = Record.size();
670      std::vector<Constant*> Elts;
671      for (unsigned i = 0; i != Size; ++i)
672        Elts.push_back(ConstantInt::get(EltTy, Record[i]));
673      V = ConstantArray::get(ATy, Elts);
674      break;
675    }
676    case bitc::CST_CODE_CSTRING: { // CSTRING: [values]
677      if (Record.empty())
678        return Error("Invalid CST_AGGREGATE record");
679
680      const ArrayType *ATy = cast<ArrayType>(CurTy);
681      const Type *EltTy = ATy->getElementType();
682
683      unsigned Size = Record.size();
684      std::vector<Constant*> Elts;
685      for (unsigned i = 0; i != Size; ++i)
686        Elts.push_back(ConstantInt::get(EltTy, Record[i]));
687      Elts.push_back(Constant::getNullValue(EltTy));
688      V = ConstantArray::get(ATy, Elts);
689      break;
690    }
691    case bitc::CST_CODE_CE_BINOP: {  // CE_BINOP: [opcode, opval, opval]
692      if (Record.size() < 3) return Error("Invalid CE_BINOP record");
693      int Opc = GetDecodedBinaryOpcode(Record[0], CurTy);
694      if (Opc < 0) {
695        V = UndefValue::get(CurTy);  // Unknown binop.
696      } else {
697        Constant *LHS = ValueList.getConstantFwdRef(Record[1], CurTy);
698        Constant *RHS = ValueList.getConstantFwdRef(Record[2], CurTy);
699        V = ConstantExpr::get(Opc, LHS, RHS);
700      }
701      break;
702    }
703    case bitc::CST_CODE_CE_CAST: {  // CE_CAST: [opcode, opty, opval]
704      if (Record.size() < 3) return Error("Invalid CE_CAST record");
705      int Opc = GetDecodedCastOpcode(Record[0]);
706      if (Opc < 0) {
707        V = UndefValue::get(CurTy);  // Unknown cast.
708      } else {
709        const Type *OpTy = getTypeByID(Record[1]);
710        if (!OpTy) return Error("Invalid CE_CAST record");
711        Constant *Op = ValueList.getConstantFwdRef(Record[2], OpTy);
712        V = ConstantExpr::getCast(Opc, Op, CurTy);
713      }
714      break;
715    }
716    case bitc::CST_CODE_CE_GEP: {  // CE_GEP:        [n x operands]
717      if (Record.size() & 1) return Error("Invalid CE_GEP record");
718      SmallVector<Constant*, 16> Elts;
719      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
720        const Type *ElTy = getTypeByID(Record[i]);
721        if (!ElTy) return Error("Invalid CE_GEP record");
722        Elts.push_back(ValueList.getConstantFwdRef(Record[i+1], ElTy));
723      }
724      V = ConstantExpr::getGetElementPtr(Elts[0], &Elts[1], Elts.size()-1);
725      break;
726    }
727    case bitc::CST_CODE_CE_SELECT:  // CE_SELECT: [opval#, opval#, opval#]
728      if (Record.size() < 3) return Error("Invalid CE_SELECT record");
729      V = ConstantExpr::getSelect(ValueList.getConstantFwdRef(Record[0],
730                                                              Type::Int1Ty),
731                                  ValueList.getConstantFwdRef(Record[1],CurTy),
732                                  ValueList.getConstantFwdRef(Record[2],CurTy));
733      break;
734    case bitc::CST_CODE_CE_EXTRACTELT: { // CE_EXTRACTELT: [opty, opval, opval]
735      if (Record.size() < 3) return Error("Invalid CE_EXTRACTELT record");
736      const VectorType *OpTy =
737        dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
738      if (OpTy == 0) return Error("Invalid CE_EXTRACTELT record");
739      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
740      Constant *Op1 = ValueList.getConstantFwdRef(Record[2],
741                                                  OpTy->getElementType());
742      V = ConstantExpr::getExtractElement(Op0, Op1);
743      break;
744    }
745    case bitc::CST_CODE_CE_INSERTELT: { // CE_INSERTELT: [opval, opval, opval]
746      const VectorType *OpTy = dyn_cast<VectorType>(CurTy);
747      if (Record.size() < 3 || OpTy == 0)
748        return Error("Invalid CE_INSERTELT record");
749      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
750      Constant *Op1 = ValueList.getConstantFwdRef(Record[1],
751                                                  OpTy->getElementType());
752      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], Type::Int32Ty);
753      V = ConstantExpr::getInsertElement(Op0, Op1, Op2);
754      break;
755    }
756    case bitc::CST_CODE_CE_SHUFFLEVEC: { // CE_SHUFFLEVEC: [opval, opval, opval]
757      const VectorType *OpTy = dyn_cast<VectorType>(CurTy);
758      if (Record.size() < 3 || OpTy == 0)
759        return Error("Invalid CE_INSERTELT record");
760      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
761      Constant *Op1 = ValueList.getConstantFwdRef(Record[1], OpTy);
762      const Type *ShufTy=VectorType::get(Type::Int32Ty, OpTy->getNumElements());
763      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], ShufTy);
764      V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
765      break;
766    }
767    case bitc::CST_CODE_CE_CMP: {     // CE_CMP: [opty, opval, opval, pred]
768      if (Record.size() < 4) return Error("Invalid CE_CMP record");
769      const Type *OpTy = getTypeByID(Record[0]);
770      if (OpTy == 0) return Error("Invalid CE_CMP record");
771      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
772      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
773
774      if (OpTy->isFloatingPoint())
775        V = ConstantExpr::getFCmp(Record[3], Op0, Op1);
776      else
777        V = ConstantExpr::getICmp(Record[3], Op0, Op1);
778      break;
779    }
780    case bitc::CST_CODE_INLINEASM: {
781      if (Record.size() < 2) return Error("Invalid INLINEASM record");
782      std::string AsmStr, ConstrStr;
783      bool HasSideEffects = Record[0];
784      unsigned AsmStrSize = Record[1];
785      if (2+AsmStrSize >= Record.size())
786        return Error("Invalid INLINEASM record");
787      unsigned ConstStrSize = Record[2+AsmStrSize];
788      if (3+AsmStrSize+ConstStrSize > Record.size())
789        return Error("Invalid INLINEASM record");
790
791      for (unsigned i = 0; i != AsmStrSize; ++i)
792        AsmStr += (char)Record[2+i];
793      for (unsigned i = 0; i != ConstStrSize; ++i)
794        ConstrStr += (char)Record[3+AsmStrSize+i];
795      const PointerType *PTy = cast<PointerType>(CurTy);
796      V = InlineAsm::get(cast<FunctionType>(PTy->getElementType()),
797                         AsmStr, ConstrStr, HasSideEffects);
798      break;
799    }
800    }
801
802    ValueList.AssignValue(V, NextCstNo);
803    ++NextCstNo;
804  }
805}
806
807/// RememberAndSkipFunctionBody - When we see the block for a function body,
808/// remember where it is and then skip it.  This lets us lazily deserialize the
809/// functions.
810bool BitcodeReader::RememberAndSkipFunctionBody() {
811  // Get the function we are talking about.
812  if (FunctionsWithBodies.empty())
813    return Error("Insufficient function protos");
814
815  Function *Fn = FunctionsWithBodies.back();
816  FunctionsWithBodies.pop_back();
817
818  // Save the current stream state.
819  uint64_t CurBit = Stream.GetCurrentBitNo();
820  DeferredFunctionInfo[Fn] = std::make_pair(CurBit, Fn->getLinkage());
821
822  // Set the functions linkage to GhostLinkage so we know it is lazily
823  // deserialized.
824  Fn->setLinkage(GlobalValue::GhostLinkage);
825
826  // Skip over the function block for now.
827  if (Stream.SkipBlock())
828    return Error("Malformed block record");
829  return false;
830}
831
832bool BitcodeReader::ParseModule(const std::string &ModuleID) {
833  // Reject multiple MODULE_BLOCK's in a single bitstream.
834  if (TheModule)
835    return Error("Multiple MODULE_BLOCKs in same stream");
836
837  if (Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
838    return Error("Malformed block record");
839
840  // Otherwise, create the module.
841  TheModule = new Module(ModuleID);
842
843  SmallVector<uint64_t, 64> Record;
844  std::vector<std::string> SectionTable;
845
846  // Read all the records for this module.
847  while (!Stream.AtEndOfStream()) {
848    unsigned Code = Stream.ReadCode();
849    if (Code == bitc::END_BLOCK) {
850      if (Stream.ReadBlockEnd())
851        return Error("Error at end of module block");
852
853      // Patch the initializers for globals and aliases up.
854      ResolveGlobalAndAliasInits();
855      if (!GlobalInits.empty() || !AliasInits.empty())
856        return Error("Malformed global initializer set");
857      if (!FunctionsWithBodies.empty())
858        return Error("Too few function bodies found");
859
860      // Force deallocation of memory for these vectors to favor the client that
861      // want lazy deserialization.
862      std::vector<std::pair<GlobalVariable*, unsigned> >().swap(GlobalInits);
863      std::vector<std::pair<GlobalAlias*, unsigned> >().swap(AliasInits);
864      std::vector<Function*>().swap(FunctionsWithBodies);
865      return false;
866    }
867
868    if (Code == bitc::ENTER_SUBBLOCK) {
869      switch (Stream.ReadSubBlockID()) {
870      default:  // Skip unknown content.
871        if (Stream.SkipBlock())
872          return Error("Malformed block record");
873        break;
874      case bitc::BLOCKINFO_BLOCK_ID:
875        if (Stream.ReadBlockInfoBlock())
876          return Error("Malformed BlockInfoBlock");
877        break;
878      case bitc::PARAMATTR_BLOCK_ID:
879        if (ParseParamAttrBlock())
880          return true;
881        break;
882      case bitc::TYPE_BLOCK_ID:
883        if (ParseTypeTable())
884          return true;
885        break;
886      case bitc::TYPE_SYMTAB_BLOCK_ID:
887        if (ParseTypeSymbolTable())
888          return true;
889        break;
890      case bitc::VALUE_SYMTAB_BLOCK_ID:
891        if (ParseValueSymbolTable())
892          return true;
893        break;
894      case bitc::CONSTANTS_BLOCK_ID:
895        if (ParseConstants() || ResolveGlobalAndAliasInits())
896          return true;
897        break;
898      case bitc::FUNCTION_BLOCK_ID:
899        // If this is the first function body we've seen, reverse the
900        // FunctionsWithBodies list.
901        if (!HasReversedFunctionsWithBodies) {
902          std::reverse(FunctionsWithBodies.begin(), FunctionsWithBodies.end());
903          HasReversedFunctionsWithBodies = true;
904        }
905
906        if (RememberAndSkipFunctionBody())
907          return true;
908        break;
909      }
910      continue;
911    }
912
913    if (Code == bitc::DEFINE_ABBREV) {
914      Stream.ReadAbbrevRecord();
915      continue;
916    }
917
918    // Read a record.
919    switch (Stream.ReadRecord(Code, Record)) {
920    default: break;  // Default behavior, ignore unknown content.
921    case bitc::MODULE_CODE_VERSION:  // VERSION: [version#]
922      if (Record.size() < 1)
923        return Error("Malformed MODULE_CODE_VERSION");
924      // Only version #0 is supported so far.
925      if (Record[0] != 0)
926        return Error("Unknown bitstream version!");
927      break;
928    case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
929      std::string S;
930      if (ConvertToString(Record, 0, S))
931        return Error("Invalid MODULE_CODE_TRIPLE record");
932      TheModule->setTargetTriple(S);
933      break;
934    }
935    case bitc::MODULE_CODE_DATALAYOUT: {  // DATALAYOUT: [strchr x N]
936      std::string S;
937      if (ConvertToString(Record, 0, S))
938        return Error("Invalid MODULE_CODE_DATALAYOUT record");
939      TheModule->setDataLayout(S);
940      break;
941    }
942    case bitc::MODULE_CODE_ASM: {  // ASM: [strchr x N]
943      std::string S;
944      if (ConvertToString(Record, 0, S))
945        return Error("Invalid MODULE_CODE_ASM record");
946      TheModule->setModuleInlineAsm(S);
947      break;
948    }
949    case bitc::MODULE_CODE_DEPLIB: {  // DEPLIB: [strchr x N]
950      std::string S;
951      if (ConvertToString(Record, 0, S))
952        return Error("Invalid MODULE_CODE_DEPLIB record");
953      TheModule->addLibrary(S);
954      break;
955    }
956    case bitc::MODULE_CODE_SECTIONNAME: {  // SECTIONNAME: [strchr x N]
957      std::string S;
958      if (ConvertToString(Record, 0, S))
959        return Error("Invalid MODULE_CODE_SECTIONNAME record");
960      SectionTable.push_back(S);
961      break;
962    }
963    // GLOBALVAR: [type, isconst, initid,
964    //             linkage, alignment, section, visibility, threadlocal]
965    case bitc::MODULE_CODE_GLOBALVAR: {
966      if (Record.size() < 6)
967        return Error("Invalid MODULE_CODE_GLOBALVAR record");
968      const Type *Ty = getTypeByID(Record[0]);
969      if (!isa<PointerType>(Ty))
970        return Error("Global not a pointer type!");
971      Ty = cast<PointerType>(Ty)->getElementType();
972
973      bool isConstant = Record[1];
974      GlobalValue::LinkageTypes Linkage = GetDecodedLinkage(Record[3]);
975      unsigned Alignment = (1 << Record[4]) >> 1;
976      std::string Section;
977      if (Record[5]) {
978        if (Record[5]-1 >= SectionTable.size())
979          return Error("Invalid section ID");
980        Section = SectionTable[Record[5]-1];
981      }
982      GlobalValue::VisibilityTypes Visibility = GlobalValue::DefaultVisibility;
983      if (Record.size() > 6)
984        Visibility = GetDecodedVisibility(Record[6]);
985      bool isThreadLocal = false;
986      if (Record.size() > 7)
987        isThreadLocal = Record[7];
988
989      GlobalVariable *NewGV =
990        new GlobalVariable(Ty, isConstant, Linkage, 0, "", TheModule);
991      NewGV->setAlignment(Alignment);
992      if (!Section.empty())
993        NewGV->setSection(Section);
994      NewGV->setVisibility(Visibility);
995      NewGV->setThreadLocal(isThreadLocal);
996
997      ValueList.push_back(NewGV);
998
999      // Remember which value to use for the global initializer.
1000      if (unsigned InitID = Record[2])
1001        GlobalInits.push_back(std::make_pair(NewGV, InitID-1));
1002      break;
1003    }
1004    // FUNCTION:  [type, callingconv, isproto, linkage, paramattr,
1005    //             alignment, section, visibility]
1006    case bitc::MODULE_CODE_FUNCTION: {
1007      if (Record.size() < 8)
1008        return Error("Invalid MODULE_CODE_FUNCTION record");
1009      const Type *Ty = getTypeByID(Record[0]);
1010      if (!isa<PointerType>(Ty))
1011        return Error("Function not a pointer type!");
1012      const FunctionType *FTy =
1013        dyn_cast<FunctionType>(cast<PointerType>(Ty)->getElementType());
1014      if (!FTy)
1015        return Error("Function not a pointer to function type!");
1016
1017      Function *Func = new Function(FTy, GlobalValue::ExternalLinkage,
1018                                    "", TheModule);
1019
1020      Func->setCallingConv(Record[1]);
1021      bool isProto = Record[2];
1022      Func->setLinkage(GetDecodedLinkage(Record[3]));
1023
1024      assert(Func->getFunctionType()->getParamAttrs() ==
1025             getParamAttrs(Record[4]));
1026
1027      Func->setAlignment((1 << Record[5]) >> 1);
1028      if (Record[6]) {
1029        if (Record[6]-1 >= SectionTable.size())
1030          return Error("Invalid section ID");
1031        Func->setSection(SectionTable[Record[6]-1]);
1032      }
1033      Func->setVisibility(GetDecodedVisibility(Record[7]));
1034
1035      ValueList.push_back(Func);
1036
1037      // If this is a function with a body, remember the prototype we are
1038      // creating now, so that we can match up the body with them later.
1039      if (!isProto)
1040        FunctionsWithBodies.push_back(Func);
1041      break;
1042    }
1043    // ALIAS: [alias type, aliasee val#, linkage]
1044    case bitc::MODULE_CODE_ALIAS: {
1045      if (Record.size() < 3)
1046        return Error("Invalid MODULE_ALIAS record");
1047      const Type *Ty = getTypeByID(Record[0]);
1048      if (!isa<PointerType>(Ty))
1049        return Error("Function not a pointer type!");
1050
1051      GlobalAlias *NewGA = new GlobalAlias(Ty, GetDecodedLinkage(Record[2]),
1052                                           "", 0, TheModule);
1053      ValueList.push_back(NewGA);
1054      AliasInits.push_back(std::make_pair(NewGA, Record[1]));
1055      break;
1056    }
1057    /// MODULE_CODE_PURGEVALS: [numvals]
1058    case bitc::MODULE_CODE_PURGEVALS:
1059      // Trim down the value list to the specified size.
1060      if (Record.size() < 1 || Record[0] > ValueList.size())
1061        return Error("Invalid MODULE_PURGEVALS record");
1062      ValueList.shrinkTo(Record[0]);
1063      break;
1064    }
1065    Record.clear();
1066  }
1067
1068  return Error("Premature end of bitstream");
1069}
1070
1071
1072bool BitcodeReader::ParseBitcode() {
1073  TheModule = 0;
1074
1075  if (Buffer->getBufferSize() & 3)
1076    return Error("Bitcode stream should be a multiple of 4 bytes in length");
1077
1078  unsigned char *BufPtr = (unsigned char *)Buffer->getBufferStart();
1079  Stream.init(BufPtr, BufPtr+Buffer->getBufferSize());
1080
1081  // Sniff for the signature.
1082  if (Stream.Read(8) != 'B' ||
1083      Stream.Read(8) != 'C' ||
1084      Stream.Read(4) != 0x0 ||
1085      Stream.Read(4) != 0xC ||
1086      Stream.Read(4) != 0xE ||
1087      Stream.Read(4) != 0xD)
1088    return Error("Invalid bitcode signature");
1089
1090  // We expect a number of well-defined blocks, though we don't necessarily
1091  // need to understand them all.
1092  while (!Stream.AtEndOfStream()) {
1093    unsigned Code = Stream.ReadCode();
1094
1095    if (Code != bitc::ENTER_SUBBLOCK)
1096      return Error("Invalid record at top-level");
1097
1098    unsigned BlockID = Stream.ReadSubBlockID();
1099
1100    // We only know the MODULE subblock ID.
1101    switch (BlockID) {
1102    case bitc::BLOCKINFO_BLOCK_ID:
1103      if (Stream.ReadBlockInfoBlock())
1104        return Error("Malformed BlockInfoBlock");
1105      break;
1106    case bitc::MODULE_BLOCK_ID:
1107      if (ParseModule(Buffer->getBufferIdentifier()))
1108        return true;
1109      break;
1110    default:
1111      if (Stream.SkipBlock())
1112        return Error("Malformed block record");
1113      break;
1114    }
1115  }
1116
1117  return false;
1118}
1119
1120
1121/// ParseFunctionBody - Lazily parse the specified function body block.
1122bool BitcodeReader::ParseFunctionBody(Function *F) {
1123  if (Stream.EnterSubBlock(bitc::FUNCTION_BLOCK_ID))
1124    return Error("Malformed block record");
1125
1126  unsigned ModuleValueListSize = ValueList.size();
1127
1128  // Add all the function arguments to the value table.
1129  for(Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
1130    ValueList.push_back(I);
1131
1132  unsigned NextValueNo = ValueList.size();
1133  BasicBlock *CurBB = 0;
1134  unsigned CurBBNo = 0;
1135
1136  // Read all the records.
1137  SmallVector<uint64_t, 64> Record;
1138  while (1) {
1139    unsigned Code = Stream.ReadCode();
1140    if (Code == bitc::END_BLOCK) {
1141      if (Stream.ReadBlockEnd())
1142        return Error("Error at end of function block");
1143      break;
1144    }
1145
1146    if (Code == bitc::ENTER_SUBBLOCK) {
1147      switch (Stream.ReadSubBlockID()) {
1148      default:  // Skip unknown content.
1149        if (Stream.SkipBlock())
1150          return Error("Malformed block record");
1151        break;
1152      case bitc::CONSTANTS_BLOCK_ID:
1153        if (ParseConstants()) return true;
1154        NextValueNo = ValueList.size();
1155        break;
1156      case bitc::VALUE_SYMTAB_BLOCK_ID:
1157        if (ParseValueSymbolTable()) return true;
1158        break;
1159      }
1160      continue;
1161    }
1162
1163    if (Code == bitc::DEFINE_ABBREV) {
1164      Stream.ReadAbbrevRecord();
1165      continue;
1166    }
1167
1168    // Read a record.
1169    Record.clear();
1170    Instruction *I = 0;
1171    switch (Stream.ReadRecord(Code, Record)) {
1172    default: // Default behavior: reject
1173      return Error("Unknown instruction");
1174    case bitc::FUNC_CODE_DECLAREBLOCKS:     // DECLAREBLOCKS: [nblocks]
1175      if (Record.size() < 1 || Record[0] == 0)
1176        return Error("Invalid DECLAREBLOCKS record");
1177      // Create all the basic blocks for the function.
1178      FunctionBBs.resize(Record[0]);
1179      for (unsigned i = 0, e = FunctionBBs.size(); i != e; ++i)
1180        FunctionBBs[i] = new BasicBlock("", F);
1181      CurBB = FunctionBBs[0];
1182      continue;
1183
1184    case bitc::FUNC_CODE_INST_BINOP: {    // BINOP: [opval, ty, opval, opcode]
1185      unsigned OpNum = 0;
1186      Value *LHS, *RHS;
1187      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
1188          getValue(Record, OpNum, LHS->getType(), RHS) ||
1189          OpNum+1 != Record.size())
1190        return Error("Invalid BINOP record");
1191
1192      int Opc = GetDecodedBinaryOpcode(Record[OpNum], LHS->getType());
1193      if (Opc == -1) return Error("Invalid BINOP record");
1194      I = BinaryOperator::create((Instruction::BinaryOps)Opc, LHS, RHS);
1195      break;
1196    }
1197    case bitc::FUNC_CODE_INST_CAST: {    // CAST: [opval, opty, destty, castopc]
1198      unsigned OpNum = 0;
1199      Value *Op;
1200      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
1201          OpNum+2 != Record.size())
1202        return Error("Invalid CAST record");
1203
1204      const Type *ResTy = getTypeByID(Record[OpNum]);
1205      int Opc = GetDecodedCastOpcode(Record[OpNum+1]);
1206      if (Opc == -1 || ResTy == 0)
1207        return Error("Invalid CAST record");
1208      I = CastInst::create((Instruction::CastOps)Opc, Op, ResTy);
1209      break;
1210    }
1211    case bitc::FUNC_CODE_INST_GEP: { // GEP: [n x operands]
1212      unsigned OpNum = 0;
1213      Value *BasePtr;
1214      if (getValueTypePair(Record, OpNum, NextValueNo, BasePtr))
1215        return Error("Invalid GEP record");
1216
1217      SmallVector<Value*, 16> GEPIdx;
1218      while (OpNum != Record.size()) {
1219        Value *Op;
1220        if (getValueTypePair(Record, OpNum, NextValueNo, Op))
1221          return Error("Invalid GEP record");
1222        GEPIdx.push_back(Op);
1223      }
1224
1225      I = new GetElementPtrInst(BasePtr, &GEPIdx[0], GEPIdx.size());
1226      break;
1227    }
1228
1229    case bitc::FUNC_CODE_INST_SELECT: { // SELECT: [opval, ty, opval, opval]
1230      unsigned OpNum = 0;
1231      Value *TrueVal, *FalseVal, *Cond;
1232      if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
1233          getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
1234          getValue(Record, OpNum, Type::Int1Ty, Cond))
1235        return Error("Invalid SELECT record");
1236
1237      I = new SelectInst(Cond, TrueVal, FalseVal);
1238      break;
1239    }
1240
1241    case bitc::FUNC_CODE_INST_EXTRACTELT: { // EXTRACTELT: [opty, opval, opval]
1242      unsigned OpNum = 0;
1243      Value *Vec, *Idx;
1244      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
1245          getValue(Record, OpNum, Type::Int32Ty, Idx))
1246        return Error("Invalid EXTRACTELT record");
1247      I = new ExtractElementInst(Vec, Idx);
1248      break;
1249    }
1250
1251    case bitc::FUNC_CODE_INST_INSERTELT: { // INSERTELT: [ty, opval,opval,opval]
1252      unsigned OpNum = 0;
1253      Value *Vec, *Elt, *Idx;
1254      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
1255          getValue(Record, OpNum,
1256                   cast<VectorType>(Vec->getType())->getElementType(), Elt) ||
1257          getValue(Record, OpNum, Type::Int32Ty, Idx))
1258        return Error("Invalid INSERTELT record");
1259      I = new InsertElementInst(Vec, Elt, Idx);
1260      break;
1261    }
1262
1263    case bitc::FUNC_CODE_INST_SHUFFLEVEC: {// SHUFFLEVEC: [opval,ty,opval,opval]
1264      unsigned OpNum = 0;
1265      Value *Vec1, *Vec2, *Mask;
1266      if (getValueTypePair(Record, OpNum, NextValueNo, Vec1) ||
1267          getValue(Record, OpNum, Vec1->getType(), Vec2))
1268        return Error("Invalid SHUFFLEVEC record");
1269
1270      const Type *MaskTy =
1271        VectorType::get(Type::Int32Ty,
1272                        cast<VectorType>(Vec1->getType())->getNumElements());
1273
1274      if (getValue(Record, OpNum, MaskTy, Mask))
1275        return Error("Invalid SHUFFLEVEC record");
1276      I = new ShuffleVectorInst(Vec1, Vec2, Mask);
1277      break;
1278    }
1279
1280    case bitc::FUNC_CODE_INST_CMP: { // CMP: [opty, opval, opval, pred]
1281      unsigned OpNum = 0;
1282      Value *LHS, *RHS;
1283      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
1284          getValue(Record, OpNum, LHS->getType(), RHS) ||
1285          OpNum+1 != Record.size())
1286        return Error("Invalid CMP record");
1287
1288      if (LHS->getType()->isFPOrFPVector())
1289        I = new FCmpInst((FCmpInst::Predicate)Record[OpNum], LHS, RHS);
1290      else
1291        I = new ICmpInst((ICmpInst::Predicate)Record[OpNum], LHS, RHS);
1292      break;
1293    }
1294
1295    case bitc::FUNC_CODE_INST_RET: // RET: [opty,opval<optional>]
1296      if (Record.size() == 0) {
1297        I = new ReturnInst();
1298        break;
1299      } else {
1300        unsigned OpNum = 0;
1301        Value *Op;
1302        if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
1303            OpNum != Record.size())
1304          return Error("Invalid RET record");
1305        I = new ReturnInst(Op);
1306        break;
1307      }
1308    case bitc::FUNC_CODE_INST_BR: { // BR: [bb#, bb#, opval] or [bb#]
1309      if (Record.size() != 1 && Record.size() != 3)
1310        return Error("Invalid BR record");
1311      BasicBlock *TrueDest = getBasicBlock(Record[0]);
1312      if (TrueDest == 0)
1313        return Error("Invalid BR record");
1314
1315      if (Record.size() == 1)
1316        I = new BranchInst(TrueDest);
1317      else {
1318        BasicBlock *FalseDest = getBasicBlock(Record[1]);
1319        Value *Cond = getFnValueByID(Record[2], Type::Int1Ty);
1320        if (FalseDest == 0 || Cond == 0)
1321          return Error("Invalid BR record");
1322        I = new BranchInst(TrueDest, FalseDest, Cond);
1323      }
1324      break;
1325    }
1326    case bitc::FUNC_CODE_INST_SWITCH: { // SWITCH: [opty, opval, n, n x ops]
1327      if (Record.size() < 3 || (Record.size() & 1) == 0)
1328        return Error("Invalid SWITCH record");
1329      const Type *OpTy = getTypeByID(Record[0]);
1330      Value *Cond = getFnValueByID(Record[1], OpTy);
1331      BasicBlock *Default = getBasicBlock(Record[2]);
1332      if (OpTy == 0 || Cond == 0 || Default == 0)
1333        return Error("Invalid SWITCH record");
1334      unsigned NumCases = (Record.size()-3)/2;
1335      SwitchInst *SI = new SwitchInst(Cond, Default, NumCases);
1336      for (unsigned i = 0, e = NumCases; i != e; ++i) {
1337        ConstantInt *CaseVal =
1338          dyn_cast_or_null<ConstantInt>(getFnValueByID(Record[3+i*2], OpTy));
1339        BasicBlock *DestBB = getBasicBlock(Record[1+3+i*2]);
1340        if (CaseVal == 0 || DestBB == 0) {
1341          delete SI;
1342          return Error("Invalid SWITCH record!");
1343        }
1344        SI->addCase(CaseVal, DestBB);
1345      }
1346      I = SI;
1347      break;
1348    }
1349
1350    case bitc::FUNC_CODE_INST_INVOKE: { // INVOKE: [cc,fnty, op0,op1,op2, ...]
1351      if (Record.size() < 4) return Error("Invalid INVOKE record");
1352      unsigned CCInfo = Record[1];
1353      BasicBlock *NormalBB = getBasicBlock(Record[2]);
1354      BasicBlock *UnwindBB = getBasicBlock(Record[3]);
1355
1356      unsigned OpNum = 4;
1357      Value *Callee;
1358      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
1359        return Error("Invalid INVOKE record");
1360
1361      const PointerType *CalleeTy = dyn_cast<PointerType>(Callee->getType());
1362      const FunctionType *FTy = !CalleeTy ? 0 :
1363        dyn_cast<FunctionType>(CalleeTy->getElementType());
1364
1365      // Check that the right number of fixed parameters are here.
1366      if (FTy == 0 || NormalBB == 0 || UnwindBB == 0 ||
1367          Record.size() < OpNum+FTy->getNumParams())
1368        return Error("Invalid INVOKE record");
1369
1370      assert(FTy->getParamAttrs() == getParamAttrs(Record[0]));
1371
1372      SmallVector<Value*, 16> Ops;
1373      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
1374        Ops.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
1375        if (Ops.back() == 0) return Error("Invalid INVOKE record");
1376      }
1377
1378      if (!FTy->isVarArg()) {
1379        if (Record.size() != OpNum)
1380          return Error("Invalid INVOKE record");
1381      } else {
1382        // Read type/value pairs for varargs params.
1383        while (OpNum != Record.size()) {
1384          Value *Op;
1385          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
1386            return Error("Invalid INVOKE record");
1387          Ops.push_back(Op);
1388        }
1389      }
1390
1391      I = new InvokeInst(Callee, NormalBB, UnwindBB, &Ops[0], Ops.size());
1392      cast<InvokeInst>(I)->setCallingConv(CCInfo);
1393      break;
1394    }
1395    case bitc::FUNC_CODE_INST_UNWIND: // UNWIND
1396      I = new UnwindInst();
1397      break;
1398    case bitc::FUNC_CODE_INST_UNREACHABLE: // UNREACHABLE
1399      I = new UnreachableInst();
1400      break;
1401    case bitc::FUNC_CODE_INST_PHI: { // PHI: [ty, val0,bb0, ...]
1402      if (Record.size() < 1 || ((Record.size()-1)&1))
1403        return Error("Invalid PHI record");
1404      const Type *Ty = getTypeByID(Record[0]);
1405      if (!Ty) return Error("Invalid PHI record");
1406
1407      PHINode *PN = new PHINode(Ty);
1408      PN->reserveOperandSpace(Record.size()-1);
1409
1410      for (unsigned i = 0, e = Record.size()-1; i != e; i += 2) {
1411        Value *V = getFnValueByID(Record[1+i], Ty);
1412        BasicBlock *BB = getBasicBlock(Record[2+i]);
1413        if (!V || !BB) return Error("Invalid PHI record");
1414        PN->addIncoming(V, BB);
1415      }
1416      I = PN;
1417      break;
1418    }
1419
1420    case bitc::FUNC_CODE_INST_MALLOC: { // MALLOC: [instty, op, align]
1421      if (Record.size() < 3)
1422        return Error("Invalid MALLOC record");
1423      const PointerType *Ty =
1424        dyn_cast_or_null<PointerType>(getTypeByID(Record[0]));
1425      Value *Size = getFnValueByID(Record[1], Type::Int32Ty);
1426      unsigned Align = Record[2];
1427      if (!Ty || !Size) return Error("Invalid MALLOC record");
1428      I = new MallocInst(Ty->getElementType(), Size, (1 << Align) >> 1);
1429      break;
1430    }
1431    case bitc::FUNC_CODE_INST_FREE: { // FREE: [op, opty]
1432      unsigned OpNum = 0;
1433      Value *Op;
1434      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
1435          OpNum != Record.size())
1436        return Error("Invalid FREE record");
1437      I = new FreeInst(Op);
1438      break;
1439    }
1440    case bitc::FUNC_CODE_INST_ALLOCA: { // ALLOCA: [instty, op, align]
1441      if (Record.size() < 3)
1442        return Error("Invalid ALLOCA record");
1443      const PointerType *Ty =
1444        dyn_cast_or_null<PointerType>(getTypeByID(Record[0]));
1445      Value *Size = getFnValueByID(Record[1], Type::Int32Ty);
1446      unsigned Align = Record[2];
1447      if (!Ty || !Size) return Error("Invalid ALLOCA record");
1448      I = new AllocaInst(Ty->getElementType(), Size, (1 << Align) >> 1);
1449      break;
1450    }
1451    case bitc::FUNC_CODE_INST_LOAD: { // LOAD: [opty, op, align, vol]
1452      unsigned OpNum = 0;
1453      Value *Op;
1454      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
1455          OpNum+2 != Record.size())
1456        return Error("Invalid LOAD record");
1457
1458      I = new LoadInst(Op, "", Record[OpNum+1], (1 << Record[OpNum]) >> 1);
1459      break;
1460    }
1461    case bitc::FUNC_CODE_INST_STORE: { // STORE:[val, valty, ptr, align, vol]
1462      unsigned OpNum = 0;
1463      Value *Val, *Ptr;
1464      if (getValueTypePair(Record, OpNum, NextValueNo, Val) ||
1465          getValue(Record, OpNum, PointerType::get(Val->getType()), Ptr) ||
1466          OpNum+2 != Record.size())
1467        return Error("Invalid STORE record");
1468
1469      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1);
1470      break;
1471    }
1472    case bitc::FUNC_CODE_INST_CALL: { // CALL: [cc, fnty, fnid, arg0, arg1...]
1473      if (Record.size() < 2)
1474        return Error("Invalid CALL record");
1475
1476      unsigned CCInfo = Record[1];
1477
1478      unsigned OpNum = 2;
1479      Value *Callee;
1480      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
1481        return Error("Invalid CALL record");
1482
1483      const PointerType *OpTy = dyn_cast<PointerType>(Callee->getType());
1484      const FunctionType *FTy = 0;
1485      if (OpTy) FTy = dyn_cast<FunctionType>(OpTy->getElementType());
1486      if (!FTy || Record.size() < FTy->getNumParams()+OpNum)
1487        return Error("Invalid CALL record");
1488
1489      assert(FTy->getParamAttrs() == getParamAttrs(Record[0]));
1490
1491      SmallVector<Value*, 16> Args;
1492      // Read the fixed params.
1493      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
1494        Args.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
1495        if (Args.back() == 0) return Error("Invalid CALL record");
1496      }
1497
1498      // Read type/value pairs for varargs params.
1499      if (!FTy->isVarArg()) {
1500        if (OpNum != Record.size())
1501          return Error("Invalid CALL record");
1502      } else {
1503        while (OpNum != Record.size()) {
1504          Value *Op;
1505          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
1506            return Error("Invalid CALL record");
1507          Args.push_back(Op);
1508        }
1509      }
1510
1511      I = new CallInst(Callee, Args.begin(), Args.end());
1512      cast<CallInst>(I)->setCallingConv(CCInfo>>1);
1513      cast<CallInst>(I)->setTailCall(CCInfo & 1);
1514      break;
1515    }
1516    case bitc::FUNC_CODE_INST_VAARG: { // VAARG: [valistty, valist, instty]
1517      if (Record.size() < 3)
1518        return Error("Invalid VAARG record");
1519      const Type *OpTy = getTypeByID(Record[0]);
1520      Value *Op = getFnValueByID(Record[1], OpTy);
1521      const Type *ResTy = getTypeByID(Record[2]);
1522      if (!OpTy || !Op || !ResTy)
1523        return Error("Invalid VAARG record");
1524      I = new VAArgInst(Op, ResTy);
1525      break;
1526    }
1527    }
1528
1529    // Add instruction to end of current BB.  If there is no current BB, reject
1530    // this file.
1531    if (CurBB == 0) {
1532      delete I;
1533      return Error("Invalid instruction with no BB");
1534    }
1535    CurBB->getInstList().push_back(I);
1536
1537    // If this was a terminator instruction, move to the next block.
1538    if (isa<TerminatorInst>(I)) {
1539      ++CurBBNo;
1540      CurBB = CurBBNo < FunctionBBs.size() ? FunctionBBs[CurBBNo] : 0;
1541    }
1542
1543    // Non-void values get registered in the value table for future use.
1544    if (I && I->getType() != Type::VoidTy)
1545      ValueList.AssignValue(I, NextValueNo++);
1546  }
1547
1548  // Check the function list for unresolved values.
1549  if (Argument *A = dyn_cast<Argument>(ValueList.back())) {
1550    if (A->getParent() == 0) {
1551      // We found at least one unresolved value.  Nuke them all to avoid leaks.
1552      for (unsigned i = ModuleValueListSize, e = ValueList.size(); i != e; ++i){
1553        if ((A = dyn_cast<Argument>(ValueList.back())) && A->getParent() == 0) {
1554          A->replaceAllUsesWith(UndefValue::get(A->getType()));
1555          delete A;
1556        }
1557      }
1558      return Error("Never resolved value found in function!");
1559    }
1560  }
1561
1562  // Trim the value list down to the size it was before we parsed this function.
1563  ValueList.shrinkTo(ModuleValueListSize);
1564  std::vector<BasicBlock*>().swap(FunctionBBs);
1565
1566  return false;
1567}
1568
1569//===----------------------------------------------------------------------===//
1570// ModuleProvider implementation
1571//===----------------------------------------------------------------------===//
1572
1573
1574bool BitcodeReader::materializeFunction(Function *F, std::string *ErrInfo) {
1575  // If it already is material, ignore the request.
1576  if (!F->hasNotBeenReadFromBitcode()) return false;
1577
1578  DenseMap<Function*, std::pair<uint64_t, unsigned> >::iterator DFII =
1579    DeferredFunctionInfo.find(F);
1580  assert(DFII != DeferredFunctionInfo.end() && "Deferred function not found!");
1581
1582  // Move the bit stream to the saved position of the deferred function body and
1583  // restore the real linkage type for the function.
1584  Stream.JumpToBit(DFII->second.first);
1585  F->setLinkage((GlobalValue::LinkageTypes)DFII->second.second);
1586
1587  if (ParseFunctionBody(F)) {
1588    if (ErrInfo) *ErrInfo = ErrorString;
1589    return true;
1590  }
1591
1592  return false;
1593}
1594
1595void BitcodeReader::dematerializeFunction(Function *F) {
1596  // If this function isn't materialized, or if it is a proto, this is a noop.
1597  if (F->hasNotBeenReadFromBitcode() || F->isDeclaration())
1598    return;
1599
1600  assert(DeferredFunctionInfo.count(F) && "No info to read function later?");
1601
1602  // Just forget the function body, we can remat it later.
1603  F->deleteBody();
1604  F->setLinkage(GlobalValue::GhostLinkage);
1605}
1606
1607
1608Module *BitcodeReader::materializeModule(std::string *ErrInfo) {
1609  for (DenseMap<Function*, std::pair<uint64_t, unsigned> >::iterator I =
1610       DeferredFunctionInfo.begin(), E = DeferredFunctionInfo.end(); I != E;
1611       ++I) {
1612    Function *F = I->first;
1613    if (F->hasNotBeenReadFromBitcode() &&
1614        materializeFunction(F, ErrInfo))
1615      return 0;
1616  }
1617  return TheModule;
1618}
1619
1620
1621/// This method is provided by the parent ModuleProvde class and overriden
1622/// here. It simply releases the module from its provided and frees up our
1623/// state.
1624/// @brief Release our hold on the generated module
1625Module *BitcodeReader::releaseModule(std::string *ErrInfo) {
1626  // Since we're losing control of this Module, we must hand it back complete
1627  Module *M = ModuleProvider::releaseModule(ErrInfo);
1628  FreeState();
1629  return M;
1630}
1631
1632
1633//===----------------------------------------------------------------------===//
1634// External interface
1635//===----------------------------------------------------------------------===//
1636
1637/// getBitcodeModuleProvider - lazy function-at-a-time loading from a file.
1638///
1639ModuleProvider *llvm::getBitcodeModuleProvider(MemoryBuffer *Buffer,
1640                                               std::string *ErrMsg) {
1641  BitcodeReader *R = new BitcodeReader(Buffer);
1642  if (R->ParseBitcode()) {
1643    if (ErrMsg)
1644      *ErrMsg = R->getErrorString();
1645
1646    // Don't let the BitcodeReader dtor delete 'Buffer'.
1647    R->releaseMemoryBuffer();
1648    delete R;
1649    return 0;
1650  }
1651  return R;
1652}
1653
1654/// ParseBitcodeFile - Read the specified bitcode file, returning the module.
1655/// If an error occurs, return null and fill in *ErrMsg if non-null.
1656Module *llvm::ParseBitcodeFile(MemoryBuffer *Buffer, std::string *ErrMsg){
1657  BitcodeReader *R;
1658  R = static_cast<BitcodeReader*>(getBitcodeModuleProvider(Buffer, ErrMsg));
1659  if (!R) return 0;
1660
1661  // Read in the entire module.
1662  Module *M = R->materializeModule(ErrMsg);
1663
1664  // Don't let the BitcodeReader dtor delete 'Buffer', regardless of whether
1665  // there was an error.
1666  R->releaseMemoryBuffer();
1667
1668  // If there was no error, tell ModuleProvider not to delete it when its dtor
1669  // is run.
1670  if (M)
1671    M = R->releaseModule(ErrMsg);
1672
1673  delete R;
1674  return M;
1675}
1676