BitcodeReader.cpp revision f9b83fcf95e8a280d7b117af8858596fe5b10d94 
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/AutoUpgrade.h"
23#include "llvm/ADT/SmallString.h"
24#include "llvm/Support/MathExtras.h"
25#include "llvm/Support/MemoryBuffer.h"
26using namespace llvm;
27
28void BitcodeReader::FreeState() {
29  delete Buffer;
30  Buffer = 0;
31  std::vector<PATypeHolder>().swap(TypeList);
32  ValueList.clear();
33  std::vector<const ParamAttrsList*>().swap(ParamAttrs);
34  std::vector<BasicBlock*>().swap(FunctionBBs);
35  std::vector<Function*>().swap(FunctionsWithBodies);
36  DeferredFunctionInfo.clear();
37}
38
39//===----------------------------------------------------------------------===//
40//  Helper functions to implement forward reference resolution, etc.
41//===----------------------------------------------------------------------===//
42
43/// ConvertToString - Convert a string from a record into an std::string, return
44/// true on failure.
45template<typename StrTy>
46static bool ConvertToString(SmallVector<uint64_t, 64> &Record, unsigned Idx,
47                            StrTy &Result) {
48  if (Idx > Record.size())
49    return true;
50
51  for (unsigned i = Idx, e = Record.size(); i != e; ++i)
52    Result += (char)Record[i];
53  return false;
54}
55
56static GlobalValue::LinkageTypes GetDecodedLinkage(unsigned Val) {
57  switch (Val) {
58  default: // Map unknown/new linkages to external
59  case 0: return GlobalValue::ExternalLinkage;
60  case 1: return GlobalValue::WeakLinkage;
61  case 2: return GlobalValue::AppendingLinkage;
62  case 3: return GlobalValue::InternalLinkage;
63  case 4: return GlobalValue::LinkOnceLinkage;
64  case 5: return GlobalValue::DLLImportLinkage;
65  case 6: return GlobalValue::DLLExportLinkage;
66  case 7: return GlobalValue::ExternalWeakLinkage;
67  }
68}
69
70static GlobalValue::VisibilityTypes GetDecodedVisibility(unsigned Val) {
71  switch (Val) {
72  default: // Map unknown visibilities to default.
73  case 0: return GlobalValue::DefaultVisibility;
74  case 1: return GlobalValue::HiddenVisibility;
75  case 2: return GlobalValue::ProtectedVisibility;
76  }
77}
78
79static int GetDecodedCastOpcode(unsigned Val) {
80  switch (Val) {
81  default: return -1;
82  case bitc::CAST_TRUNC   : return Instruction::Trunc;
83  case bitc::CAST_ZEXT    : return Instruction::ZExt;
84  case bitc::CAST_SEXT    : return Instruction::SExt;
85  case bitc::CAST_FPTOUI  : return Instruction::FPToUI;
86  case bitc::CAST_FPTOSI  : return Instruction::FPToSI;
87  case bitc::CAST_UITOFP  : return Instruction::UIToFP;
88  case bitc::CAST_SITOFP  : return Instruction::SIToFP;
89  case bitc::CAST_FPTRUNC : return Instruction::FPTrunc;
90  case bitc::CAST_FPEXT   : return Instruction::FPExt;
91  case bitc::CAST_PTRTOINT: return Instruction::PtrToInt;
92  case bitc::CAST_INTTOPTR: return Instruction::IntToPtr;
93  case bitc::CAST_BITCAST : return Instruction::BitCast;
94  }
95}
96static int GetDecodedBinaryOpcode(unsigned Val, const Type *Ty) {
97  switch (Val) {
98  default: return -1;
99  case bitc::BINOP_ADD:  return Instruction::Add;
100  case bitc::BINOP_SUB:  return Instruction::Sub;
101  case bitc::BINOP_MUL:  return Instruction::Mul;
102  case bitc::BINOP_UDIV: return Instruction::UDiv;
103  case bitc::BINOP_SDIV:
104    return Ty->isFPOrFPVector() ? Instruction::FDiv : Instruction::SDiv;
105  case bitc::BINOP_UREM: return Instruction::URem;
106  case bitc::BINOP_SREM:
107    return Ty->isFPOrFPVector() ? Instruction::FRem : Instruction::SRem;
108  case bitc::BINOP_SHL:  return Instruction::Shl;
109  case bitc::BINOP_LSHR: return Instruction::LShr;
110  case bitc::BINOP_ASHR: return Instruction::AShr;
111  case bitc::BINOP_AND:  return Instruction::And;
112  case bitc::BINOP_OR:   return Instruction::Or;
113  case bitc::BINOP_XOR:  return Instruction::Xor;
114  }
115}
116
117
118namespace {
119  /// @brief A class for maintaining the slot number definition
120  /// as a placeholder for the actual definition for forward constants defs.
121  class ConstantPlaceHolder : public ConstantExpr {
122    ConstantPlaceHolder();                       // DO NOT IMPLEMENT
123    void operator=(const ConstantPlaceHolder &); // DO NOT IMPLEMENT
124  public:
125    Use Op;
126    explicit ConstantPlaceHolder(const Type *Ty)
127      : ConstantExpr(Ty, Instruction::UserOp1, &Op, 1),
128        Op(UndefValue::get(Type::Int32Ty), this) {
129    }
130  };
131}
132
133Constant *BitcodeReaderValueList::getConstantFwdRef(unsigned Idx,
134                                                    const Type *Ty) {
135  if (Idx >= size()) {
136    // Insert a bunch of null values.
137    Uses.resize(Idx+1);
138    OperandList = &Uses[0];
139    NumOperands = Idx+1;
140  }
141
142  if (Value *V = Uses[Idx]) {
143    assert(Ty == V->getType() && "Type mismatch in constant table!");
144    return cast<Constant>(V);
145  }
146
147  // Create and return a placeholder, which will later be RAUW'd.
148  Constant *C = new ConstantPlaceHolder(Ty);
149  Uses[Idx].init(C, this);
150  return C;
151}
152
153Value *BitcodeReaderValueList::getValueFwdRef(unsigned Idx, const Type *Ty) {
154  if (Idx >= size()) {
155    // Insert a bunch of null values.
156    Uses.resize(Idx+1);
157    OperandList = &Uses[0];
158    NumOperands = Idx+1;
159  }
160
161  if (Value *V = Uses[Idx]) {
162    assert((Ty == 0 || Ty == V->getType()) && "Type mismatch in value table!");
163    return V;
164  }
165
166  // No type specified, must be invalid reference.
167  if (Ty == 0) return 0;
168
169  // Create and return a placeholder, which will later be RAUW'd.
170  Value *V = new Argument(Ty);
171  Uses[Idx].init(V, this);
172  return V;
173}
174
175
176const Type *BitcodeReader::getTypeByID(unsigned ID, bool isTypeTable) {
177  // If the TypeID is in range, return it.
178  if (ID < TypeList.size())
179    return TypeList[ID].get();
180  if (!isTypeTable) return 0;
181
182  // The type table allows forward references.  Push as many Opaque types as
183  // needed to get up to ID.
184  while (TypeList.size() <= ID)
185    TypeList.push_back(OpaqueType::get());
186  return TypeList.back().get();
187}
188
189//===----------------------------------------------------------------------===//
190//  Functions for parsing blocks from the bitcode file
191//===----------------------------------------------------------------------===//
192
193bool BitcodeReader::ParseParamAttrBlock() {
194  if (Stream.EnterSubBlock(bitc::PARAMATTR_BLOCK_ID))
195    return Error("Malformed block record");
196
197  if (!ParamAttrs.empty())
198    return Error("Multiple PARAMATTR blocks found!");
199
200  SmallVector<uint64_t, 64> Record;
201
202  ParamAttrsVector Attrs;
203
204  // Read all the records.
205  while (1) {
206    unsigned Code = Stream.ReadCode();
207    if (Code == bitc::END_BLOCK) {
208      if (Stream.ReadBlockEnd())
209        return Error("Error at end of PARAMATTR block");
210      return false;
211    }
212
213    if (Code == bitc::ENTER_SUBBLOCK) {
214      // No known subblocks, always skip them.
215      Stream.ReadSubBlockID();
216      if (Stream.SkipBlock())
217        return Error("Malformed block record");
218      continue;
219    }
220
221    if (Code == bitc::DEFINE_ABBREV) {
222      Stream.ReadAbbrevRecord();
223      continue;
224    }
225
226    // Read a record.
227    Record.clear();
228    switch (Stream.ReadRecord(Code, Record)) {
229    default:  // Default behavior: ignore.
230      break;
231    case bitc::PARAMATTR_CODE_ENTRY: { // ENTRY: [paramidx0, attr0, ...]
232      if (Record.size() & 1)
233        return Error("Invalid ENTRY record");
234
235      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
236        if (Record[i+1] != ParamAttr::None)
237          Attrs.push_back(ParamAttrsWithIndex::get(Record[i], Record[i+1]));
238      }
239      ParamAttrs.push_back(Attrs.empty() ? NULL : ParamAttrsList::get(Attrs));
240      Attrs.clear();
241      break;
242    }
243    }
244  }
245}
246
247
248bool BitcodeReader::ParseTypeTable() {
249  if (Stream.EnterSubBlock(bitc::TYPE_BLOCK_ID))
250    return Error("Malformed block record");
251
252  if (!TypeList.empty())
253    return Error("Multiple TYPE_BLOCKs found!");
254
255  SmallVector<uint64_t, 64> Record;
256  unsigned NumRecords = 0;
257
258  // Read all the records for this type table.
259  while (1) {
260    unsigned Code = Stream.ReadCode();
261    if (Code == bitc::END_BLOCK) {
262      if (NumRecords != TypeList.size())
263        return Error("Invalid type forward reference in TYPE_BLOCK");
264      if (Stream.ReadBlockEnd())
265        return Error("Error at end of type table block");
266      return false;
267    }
268
269    if (Code == bitc::ENTER_SUBBLOCK) {
270      // No known subblocks, always skip them.
271      Stream.ReadSubBlockID();
272      if (Stream.SkipBlock())
273        return Error("Malformed block record");
274      continue;
275    }
276
277    if (Code == bitc::DEFINE_ABBREV) {
278      Stream.ReadAbbrevRecord();
279      continue;
280    }
281
282    // Read a record.
283    Record.clear();
284    const Type *ResultTy = 0;
285    switch (Stream.ReadRecord(Code, Record)) {
286    default:  // Default behavior: unknown type.
287      ResultTy = 0;
288      break;
289    case bitc::TYPE_CODE_NUMENTRY: // TYPE_CODE_NUMENTRY: [numentries]
290      // TYPE_CODE_NUMENTRY contains a count of the number of types in the
291      // type list.  This allows us to reserve space.
292      if (Record.size() < 1)
293        return Error("Invalid TYPE_CODE_NUMENTRY record");
294      TypeList.reserve(Record[0]);
295      continue;
296    case bitc::TYPE_CODE_VOID:      // VOID
297      ResultTy = Type::VoidTy;
298      break;
299    case bitc::TYPE_CODE_FLOAT:     // FLOAT
300      ResultTy = Type::FloatTy;
301      break;
302    case bitc::TYPE_CODE_DOUBLE:    // DOUBLE
303      ResultTy = Type::DoubleTy;
304      break;
305    case bitc::TYPE_CODE_X86_FP80:  // X86_FP80
306      ResultTy = Type::X86_FP80Ty;
307      break;
308    case bitc::TYPE_CODE_FP128:     // FP128
309      ResultTy = Type::FP128Ty;
310      break;
311    case bitc::TYPE_CODE_PPC_FP128: // PPC_FP128
312      ResultTy = Type::PPC_FP128Ty;
313      break;
314    case bitc::TYPE_CODE_LABEL:     // LABEL
315      ResultTy = Type::LabelTy;
316      break;
317    case bitc::TYPE_CODE_OPAQUE:    // OPAQUE
318      ResultTy = 0;
319      break;
320    case bitc::TYPE_CODE_INTEGER:   // INTEGER: [width]
321      if (Record.size() < 1)
322        return Error("Invalid Integer type record");
323
324      ResultTy = IntegerType::get(Record[0]);
325      break;
326    case bitc::TYPE_CODE_POINTER: { // POINTER: [pointee type] or
327                                    //          [pointee type, address space]
328      if (Record.size() < 1)
329        return Error("Invalid POINTER type record");
330      unsigned AddressSpace = 0;
331      if (Record.size() == 2)
332        AddressSpace = Record[1];
333      ResultTy = PointerType::get(getTypeByID(Record[0], true), AddressSpace);
334      break;
335    }
336    case bitc::TYPE_CODE_FUNCTION: {
337      // FIXME: attrid is dead, remove it in LLVM 3.0
338      // FUNCTION: [vararg, attrid, retty, paramty x N]
339      if (Record.size() < 3)
340        return Error("Invalid FUNCTION type record");
341      std::vector<const Type*> ArgTys;
342      for (unsigned i = 3, e = Record.size(); i != e; ++i)
343        ArgTys.push_back(getTypeByID(Record[i], true));
344
345      ResultTy = FunctionType::get(getTypeByID(Record[2], true), ArgTys,
346                                   Record[0]);
347      break;
348    }
349    case bitc::TYPE_CODE_STRUCT: {  // STRUCT: [ispacked, eltty x N]
350      if (Record.size() < 1)
351        return Error("Invalid STRUCT type record");
352      std::vector<const Type*> EltTys;
353      for (unsigned i = 1, e = Record.size(); i != e; ++i)
354        EltTys.push_back(getTypeByID(Record[i], true));
355      ResultTy = StructType::get(EltTys, Record[0]);
356      break;
357    }
358    case bitc::TYPE_CODE_ARRAY:     // ARRAY: [numelts, eltty]
359      if (Record.size() < 2)
360        return Error("Invalid ARRAY type record");
361      ResultTy = ArrayType::get(getTypeByID(Record[1], true), Record[0]);
362      break;
363    case bitc::TYPE_CODE_VECTOR:    // VECTOR: [numelts, eltty]
364      if (Record.size() < 2)
365        return Error("Invalid VECTOR type record");
366      ResultTy = VectorType::get(getTypeByID(Record[1], true), Record[0]);
367      break;
368    }
369
370    if (NumRecords == TypeList.size()) {
371      // If this is a new type slot, just append it.
372      TypeList.push_back(ResultTy ? ResultTy : OpaqueType::get());
373      ++NumRecords;
374    } else if (ResultTy == 0) {
375      // Otherwise, this was forward referenced, so an opaque type was created,
376      // but the result type is actually just an opaque.  Leave the one we
377      // created previously.
378      ++NumRecords;
379    } else {
380      // Otherwise, this was forward referenced, so an opaque type was created.
381      // Resolve the opaque type to the real type now.
382      assert(NumRecords < TypeList.size() && "Typelist imbalance");
383      const OpaqueType *OldTy = cast<OpaqueType>(TypeList[NumRecords++].get());
384
385      // Don't directly push the new type on the Tab. Instead we want to replace
386      // the opaque type we previously inserted with the new concrete value. The
387      // refinement from the abstract (opaque) type to the new type causes all
388      // uses of the abstract type to use the concrete type (NewTy). This will
389      // also cause the opaque type to be deleted.
390      const_cast<OpaqueType*>(OldTy)->refineAbstractTypeTo(ResultTy);
391
392      // This should have replaced the old opaque type with the new type in the
393      // value table... or with a preexisting type that was already in the
394      // system.  Let's just make sure it did.
395      assert(TypeList[NumRecords-1].get() != OldTy &&
396             "refineAbstractType didn't work!");
397    }
398  }
399}
400
401
402bool BitcodeReader::ParseTypeSymbolTable() {
403  if (Stream.EnterSubBlock(bitc::TYPE_SYMTAB_BLOCK_ID))
404    return Error("Malformed block record");
405
406  SmallVector<uint64_t, 64> Record;
407
408  // Read all the records for this type table.
409  std::string TypeName;
410  while (1) {
411    unsigned Code = Stream.ReadCode();
412    if (Code == bitc::END_BLOCK) {
413      if (Stream.ReadBlockEnd())
414        return Error("Error at end of type symbol table block");
415      return false;
416    }
417
418    if (Code == bitc::ENTER_SUBBLOCK) {
419      // No known subblocks, always skip them.
420      Stream.ReadSubBlockID();
421      if (Stream.SkipBlock())
422        return Error("Malformed block record");
423      continue;
424    }
425
426    if (Code == bitc::DEFINE_ABBREV) {
427      Stream.ReadAbbrevRecord();
428      continue;
429    }
430
431    // Read a record.
432    Record.clear();
433    switch (Stream.ReadRecord(Code, Record)) {
434    default:  // Default behavior: unknown type.
435      break;
436    case bitc::TST_CODE_ENTRY:    // TST_ENTRY: [typeid, namechar x N]
437      if (ConvertToString(Record, 1, TypeName))
438        return Error("Invalid TST_ENTRY record");
439      unsigned TypeID = Record[0];
440      if (TypeID >= TypeList.size())
441        return Error("Invalid Type ID in TST_ENTRY record");
442
443      TheModule->addTypeName(TypeName, TypeList[TypeID].get());
444      TypeName.clear();
445      break;
446    }
447  }
448}
449
450bool BitcodeReader::ParseValueSymbolTable() {
451  if (Stream.EnterSubBlock(bitc::VALUE_SYMTAB_BLOCK_ID))
452    return Error("Malformed block record");
453
454  SmallVector<uint64_t, 64> Record;
455
456  // Read all the records for this value table.
457  SmallString<128> ValueName;
458  while (1) {
459    unsigned Code = Stream.ReadCode();
460    if (Code == bitc::END_BLOCK) {
461      if (Stream.ReadBlockEnd())
462        return Error("Error at end of value symbol table block");
463      return false;
464    }
465    if (Code == bitc::ENTER_SUBBLOCK) {
466      // No known subblocks, always skip them.
467      Stream.ReadSubBlockID();
468      if (Stream.SkipBlock())
469        return Error("Malformed block record");
470      continue;
471    }
472
473    if (Code == bitc::DEFINE_ABBREV) {
474      Stream.ReadAbbrevRecord();
475      continue;
476    }
477
478    // Read a record.
479    Record.clear();
480    switch (Stream.ReadRecord(Code, Record)) {
481    default:  // Default behavior: unknown type.
482      break;
483    case bitc::VST_CODE_ENTRY: {  // VST_ENTRY: [valueid, namechar x N]
484      if (ConvertToString(Record, 1, ValueName))
485        return Error("Invalid TST_ENTRY record");
486      unsigned ValueID = Record[0];
487      if (ValueID >= ValueList.size())
488        return Error("Invalid Value ID in VST_ENTRY record");
489      Value *V = ValueList[ValueID];
490
491      V->setName(&ValueName[0], ValueName.size());
492      ValueName.clear();
493      break;
494    }
495    case bitc::VST_CODE_BBENTRY: {
496      if (ConvertToString(Record, 1, ValueName))
497        return Error("Invalid VST_BBENTRY record");
498      BasicBlock *BB = getBasicBlock(Record[0]);
499      if (BB == 0)
500        return Error("Invalid BB ID in VST_BBENTRY record");
501
502      BB->setName(&ValueName[0], ValueName.size());
503      ValueName.clear();
504      break;
505    }
506    }
507  }
508}
509
510/// DecodeSignRotatedValue - Decode a signed value stored with the sign bit in
511/// the LSB for dense VBR encoding.
512static uint64_t DecodeSignRotatedValue(uint64_t V) {
513  if ((V & 1) == 0)
514    return V >> 1;
515  if (V != 1)
516    return -(V >> 1);
517  // There is no such thing as -0 with integers.  "-0" really means MININT.
518  return 1ULL << 63;
519}
520
521/// ResolveGlobalAndAliasInits - Resolve all of the initializers for global
522/// values and aliases that we can.
523bool BitcodeReader::ResolveGlobalAndAliasInits() {
524  std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInitWorklist;
525  std::vector<std::pair<GlobalAlias*, unsigned> > AliasInitWorklist;
526
527  GlobalInitWorklist.swap(GlobalInits);
528  AliasInitWorklist.swap(AliasInits);
529
530  while (!GlobalInitWorklist.empty()) {
531    unsigned ValID = GlobalInitWorklist.back().second;
532    if (ValID >= ValueList.size()) {
533      // Not ready to resolve this yet, it requires something later in the file.
534      GlobalInits.push_back(GlobalInitWorklist.back());
535    } else {
536      if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
537        GlobalInitWorklist.back().first->setInitializer(C);
538      else
539        return Error("Global variable initializer is not a constant!");
540    }
541    GlobalInitWorklist.pop_back();
542  }
543
544  while (!AliasInitWorklist.empty()) {
545    unsigned ValID = AliasInitWorklist.back().second;
546    if (ValID >= ValueList.size()) {
547      AliasInits.push_back(AliasInitWorklist.back());
548    } else {
549      if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
550        AliasInitWorklist.back().first->setAliasee(C);
551      else
552        return Error("Alias initializer is not a constant!");
553    }
554    AliasInitWorklist.pop_back();
555  }
556  return false;
557}
558
559
560bool BitcodeReader::ParseConstants() {
561  if (Stream.EnterSubBlock(bitc::CONSTANTS_BLOCK_ID))
562    return Error("Malformed block record");
563
564  SmallVector<uint64_t, 64> Record;
565
566  // Read all the records for this value table.
567  const Type *CurTy = Type::Int32Ty;
568  unsigned NextCstNo = ValueList.size();
569  while (1) {
570    unsigned Code = Stream.ReadCode();
571    if (Code == bitc::END_BLOCK) {
572      if (NextCstNo != ValueList.size())
573        return Error("Invalid constant reference!");
574
575      if (Stream.ReadBlockEnd())
576        return Error("Error at end of constants block");
577      return false;
578    }
579
580    if (Code == bitc::ENTER_SUBBLOCK) {
581      // No known subblocks, always skip them.
582      Stream.ReadSubBlockID();
583      if (Stream.SkipBlock())
584        return Error("Malformed block record");
585      continue;
586    }
587
588    if (Code == bitc::DEFINE_ABBREV) {
589      Stream.ReadAbbrevRecord();
590      continue;
591    }
592
593    // Read a record.
594    Record.clear();
595    Value *V = 0;
596    switch (Stream.ReadRecord(Code, Record)) {
597    default:  // Default behavior: unknown constant
598    case bitc::CST_CODE_UNDEF:     // UNDEF
599      V = UndefValue::get(CurTy);
600      break;
601    case bitc::CST_CODE_SETTYPE:   // SETTYPE: [typeid]
602      if (Record.empty())
603        return Error("Malformed CST_SETTYPE record");
604      if (Record[0] >= TypeList.size())
605        return Error("Invalid Type ID in CST_SETTYPE record");
606      CurTy = TypeList[Record[0]];
607      continue;  // Skip the ValueList manipulation.
608    case bitc::CST_CODE_NULL:      // NULL
609      V = Constant::getNullValue(CurTy);
610      break;
611    case bitc::CST_CODE_INTEGER:   // INTEGER: [intval]
612      if (!isa<IntegerType>(CurTy) || Record.empty())
613        return Error("Invalid CST_INTEGER record");
614      V = ConstantInt::get(CurTy, DecodeSignRotatedValue(Record[0]));
615      break;
616    case bitc::CST_CODE_WIDE_INTEGER: {// WIDE_INTEGER: [n x intval]
617      if (!isa<IntegerType>(CurTy) || Record.empty())
618        return Error("Invalid WIDE_INTEGER record");
619
620      unsigned NumWords = Record.size();
621      SmallVector<uint64_t, 8> Words;
622      Words.resize(NumWords);
623      for (unsigned i = 0; i != NumWords; ++i)
624        Words[i] = DecodeSignRotatedValue(Record[i]);
625      V = ConstantInt::get(APInt(cast<IntegerType>(CurTy)->getBitWidth(),
626                                 NumWords, &Words[0]));
627      break;
628    }
629    case bitc::CST_CODE_FLOAT: {    // FLOAT: [fpval]
630      if (Record.empty())
631        return Error("Invalid FLOAT record");
632      if (CurTy == Type::FloatTy)
633        V = ConstantFP::get(CurTy, APFloat(APInt(32, (uint32_t)Record[0])));
634      else if (CurTy == Type::DoubleTy)
635        V = ConstantFP::get(CurTy, APFloat(APInt(64, Record[0])));
636      else if (CurTy == Type::X86_FP80Ty)
637        V = ConstantFP::get(CurTy, APFloat(APInt(80, 2, &Record[0])));
638      else if (CurTy == Type::FP128Ty)
639        V = ConstantFP::get(CurTy, APFloat(APInt(128, 2, &Record[0]), true));
640      else if (CurTy == Type::PPC_FP128Ty)
641        V = ConstantFP::get(CurTy, APFloat(APInt(128, 2, &Record[0])));
642      else
643        V = UndefValue::get(CurTy);
644      break;
645    }
646
647    case bitc::CST_CODE_AGGREGATE: {// AGGREGATE: [n x value number]
648      if (Record.empty())
649        return Error("Invalid CST_AGGREGATE record");
650
651      unsigned Size = Record.size();
652      std::vector<Constant*> Elts;
653
654      if (const StructType *STy = dyn_cast<StructType>(CurTy)) {
655        for (unsigned i = 0; i != Size; ++i)
656          Elts.push_back(ValueList.getConstantFwdRef(Record[i],
657                                                     STy->getElementType(i)));
658        V = ConstantStruct::get(STy, Elts);
659      } else if (const ArrayType *ATy = dyn_cast<ArrayType>(CurTy)) {
660        const Type *EltTy = ATy->getElementType();
661        for (unsigned i = 0; i != Size; ++i)
662          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
663        V = ConstantArray::get(ATy, Elts);
664      } else if (const VectorType *VTy = dyn_cast<VectorType>(CurTy)) {
665        const Type *EltTy = VTy->getElementType();
666        for (unsigned i = 0; i != Size; ++i)
667          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
668        V = ConstantVector::get(Elts);
669      } else {
670        V = UndefValue::get(CurTy);
671      }
672      break;
673    }
674    case bitc::CST_CODE_STRING: { // STRING: [values]
675      if (Record.empty())
676        return Error("Invalid CST_AGGREGATE record");
677
678      const ArrayType *ATy = cast<ArrayType>(CurTy);
679      const Type *EltTy = ATy->getElementType();
680
681      unsigned Size = Record.size();
682      std::vector<Constant*> Elts;
683      for (unsigned i = 0; i != Size; ++i)
684        Elts.push_back(ConstantInt::get(EltTy, Record[i]));
685      V = ConstantArray::get(ATy, Elts);
686      break;
687    }
688    case bitc::CST_CODE_CSTRING: { // CSTRING: [values]
689      if (Record.empty())
690        return Error("Invalid CST_AGGREGATE record");
691
692      const ArrayType *ATy = cast<ArrayType>(CurTy);
693      const Type *EltTy = ATy->getElementType();
694
695      unsigned Size = Record.size();
696      std::vector<Constant*> Elts;
697      for (unsigned i = 0; i != Size; ++i)
698        Elts.push_back(ConstantInt::get(EltTy, Record[i]));
699      Elts.push_back(Constant::getNullValue(EltTy));
700      V = ConstantArray::get(ATy, Elts);
701      break;
702    }
703    case bitc::CST_CODE_CE_BINOP: {  // CE_BINOP: [opcode, opval, opval]
704      if (Record.size() < 3) return Error("Invalid CE_BINOP record");
705      int Opc = GetDecodedBinaryOpcode(Record[0], CurTy);
706      if (Opc < 0) {
707        V = UndefValue::get(CurTy);  // Unknown binop.
708      } else {
709        Constant *LHS = ValueList.getConstantFwdRef(Record[1], CurTy);
710        Constant *RHS = ValueList.getConstantFwdRef(Record[2], CurTy);
711        V = ConstantExpr::get(Opc, LHS, RHS);
712      }
713      break;
714    }
715    case bitc::CST_CODE_CE_CAST: {  // CE_CAST: [opcode, opty, opval]
716      if (Record.size() < 3) return Error("Invalid CE_CAST record");
717      int Opc = GetDecodedCastOpcode(Record[0]);
718      if (Opc < 0) {
719        V = UndefValue::get(CurTy);  // Unknown cast.
720      } else {
721        const Type *OpTy = getTypeByID(Record[1]);
722        if (!OpTy) return Error("Invalid CE_CAST record");
723        Constant *Op = ValueList.getConstantFwdRef(Record[2], OpTy);
724        V = ConstantExpr::getCast(Opc, Op, CurTy);
725      }
726      break;
727    }
728    case bitc::CST_CODE_CE_GEP: {  // CE_GEP:        [n x operands]
729      if (Record.size() & 1) return Error("Invalid CE_GEP record");
730      SmallVector<Constant*, 16> Elts;
731      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
732        const Type *ElTy = getTypeByID(Record[i]);
733        if (!ElTy) return Error("Invalid CE_GEP record");
734        Elts.push_back(ValueList.getConstantFwdRef(Record[i+1], ElTy));
735      }
736      V = ConstantExpr::getGetElementPtr(Elts[0], &Elts[1], Elts.size()-1);
737      break;
738    }
739    case bitc::CST_CODE_CE_SELECT:  // CE_SELECT: [opval#, opval#, opval#]
740      if (Record.size() < 3) return Error("Invalid CE_SELECT record");
741      V = ConstantExpr::getSelect(ValueList.getConstantFwdRef(Record[0],
742                                                              Type::Int1Ty),
743                                  ValueList.getConstantFwdRef(Record[1],CurTy),
744                                  ValueList.getConstantFwdRef(Record[2],CurTy));
745      break;
746    case bitc::CST_CODE_CE_EXTRACTELT: { // CE_EXTRACTELT: [opty, opval, opval]
747      if (Record.size() < 3) return Error("Invalid CE_EXTRACTELT record");
748      const VectorType *OpTy =
749        dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
750      if (OpTy == 0) return Error("Invalid CE_EXTRACTELT record");
751      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
752      Constant *Op1 = ValueList.getConstantFwdRef(Record[2],
753                                                  OpTy->getElementType());
754      V = ConstantExpr::getExtractElement(Op0, Op1);
755      break;
756    }
757    case bitc::CST_CODE_CE_INSERTELT: { // CE_INSERTELT: [opval, opval, opval]
758      const VectorType *OpTy = dyn_cast<VectorType>(CurTy);
759      if (Record.size() < 3 || OpTy == 0)
760        return Error("Invalid CE_INSERTELT record");
761      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
762      Constant *Op1 = ValueList.getConstantFwdRef(Record[1],
763                                                  OpTy->getElementType());
764      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], Type::Int32Ty);
765      V = ConstantExpr::getInsertElement(Op0, Op1, Op2);
766      break;
767    }
768    case bitc::CST_CODE_CE_SHUFFLEVEC: { // CE_SHUFFLEVEC: [opval, opval, opval]
769      const VectorType *OpTy = dyn_cast<VectorType>(CurTy);
770      if (Record.size() < 3 || OpTy == 0)
771        return Error("Invalid CE_INSERTELT record");
772      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
773      Constant *Op1 = ValueList.getConstantFwdRef(Record[1], OpTy);
774      const Type *ShufTy=VectorType::get(Type::Int32Ty, OpTy->getNumElements());
775      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], ShufTy);
776      V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
777      break;
778    }
779    case bitc::CST_CODE_CE_CMP: {     // CE_CMP: [opty, opval, opval, pred]
780      if (Record.size() < 4) return Error("Invalid CE_CMP record");
781      const Type *OpTy = getTypeByID(Record[0]);
782      if (OpTy == 0) return Error("Invalid CE_CMP record");
783      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
784      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
785
786      if (OpTy->isFloatingPoint())
787        V = ConstantExpr::getFCmp(Record[3], Op0, Op1);
788      else
789        V = ConstantExpr::getICmp(Record[3], Op0, Op1);
790      break;
791    }
792    case bitc::CST_CODE_INLINEASM: {
793      if (Record.size() < 2) return Error("Invalid INLINEASM record");
794      std::string AsmStr, ConstrStr;
795      bool HasSideEffects = Record[0];
796      unsigned AsmStrSize = Record[1];
797      if (2+AsmStrSize >= Record.size())
798        return Error("Invalid INLINEASM record");
799      unsigned ConstStrSize = Record[2+AsmStrSize];
800      if (3+AsmStrSize+ConstStrSize > Record.size())
801        return Error("Invalid INLINEASM record");
802
803      for (unsigned i = 0; i != AsmStrSize; ++i)
804        AsmStr += (char)Record[2+i];
805      for (unsigned i = 0; i != ConstStrSize; ++i)
806        ConstrStr += (char)Record[3+AsmStrSize+i];
807      const PointerType *PTy = cast<PointerType>(CurTy);
808      V = InlineAsm::get(cast<FunctionType>(PTy->getElementType()),
809                         AsmStr, ConstrStr, HasSideEffects);
810      break;
811    }
812    }
813
814    ValueList.AssignValue(V, NextCstNo);
815    ++NextCstNo;
816  }
817}
818
819/// RememberAndSkipFunctionBody - When we see the block for a function body,
820/// remember where it is and then skip it.  This lets us lazily deserialize the
821/// functions.
822bool BitcodeReader::RememberAndSkipFunctionBody() {
823  // Get the function we are talking about.
824  if (FunctionsWithBodies.empty())
825    return Error("Insufficient function protos");
826
827  Function *Fn = FunctionsWithBodies.back();
828  FunctionsWithBodies.pop_back();
829
830  // Save the current stream state.
831  uint64_t CurBit = Stream.GetCurrentBitNo();
832  DeferredFunctionInfo[Fn] = std::make_pair(CurBit, Fn->getLinkage());
833
834  // Set the functions linkage to GhostLinkage so we know it is lazily
835  // deserialized.
836  Fn->setLinkage(GlobalValue::GhostLinkage);
837
838  // Skip over the function block for now.
839  if (Stream.SkipBlock())
840    return Error("Malformed block record");
841  return false;
842}
843
844bool BitcodeReader::ParseModule(const std::string &ModuleID) {
845  // Reject multiple MODULE_BLOCK's in a single bitstream.
846  if (TheModule)
847    return Error("Multiple MODULE_BLOCKs in same stream");
848
849  if (Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
850    return Error("Malformed block record");
851
852  // Otherwise, create the module.
853  TheModule = new Module(ModuleID);
854
855  SmallVector<uint64_t, 64> Record;
856  std::vector<std::string> SectionTable;
857  std::vector<std::string> CollectorTable;
858
859  // Read all the records for this module.
860  while (!Stream.AtEndOfStream()) {
861    unsigned Code = Stream.ReadCode();
862    if (Code == bitc::END_BLOCK) {
863      if (Stream.ReadBlockEnd())
864        return Error("Error at end of module block");
865
866      // Patch the initializers for globals and aliases up.
867      ResolveGlobalAndAliasInits();
868      if (!GlobalInits.empty() || !AliasInits.empty())
869        return Error("Malformed global initializer set");
870      if (!FunctionsWithBodies.empty())
871        return Error("Too few function bodies found");
872
873      // Look for intrinsic functions which need to be upgraded at some point
874      for (Module::iterator FI = TheModule->begin(), FE = TheModule->end();
875           FI != FE; ++FI) {
876        Function* NewFn;
877        if (UpgradeIntrinsicFunction(FI, NewFn))
878          UpgradedIntrinsics.push_back(std::make_pair(FI, NewFn));
879      }
880
881      // Force deallocation of memory for these vectors to favor the client that
882      // want lazy deserialization.
883      std::vector<std::pair<GlobalVariable*, unsigned> >().swap(GlobalInits);
884      std::vector<std::pair<GlobalAlias*, unsigned> >().swap(AliasInits);
885      std::vector<Function*>().swap(FunctionsWithBodies);
886      return false;
887    }
888
889    if (Code == bitc::ENTER_SUBBLOCK) {
890      switch (Stream.ReadSubBlockID()) {
891      default:  // Skip unknown content.
892        if (Stream.SkipBlock())
893          return Error("Malformed block record");
894        break;
895      case bitc::BLOCKINFO_BLOCK_ID:
896        if (Stream.ReadBlockInfoBlock())
897          return Error("Malformed BlockInfoBlock");
898        break;
899      case bitc::PARAMATTR_BLOCK_ID:
900        if (ParseParamAttrBlock())
901          return true;
902        break;
903      case bitc::TYPE_BLOCK_ID:
904        if (ParseTypeTable())
905          return true;
906        break;
907      case bitc::TYPE_SYMTAB_BLOCK_ID:
908        if (ParseTypeSymbolTable())
909          return true;
910        break;
911      case bitc::VALUE_SYMTAB_BLOCK_ID:
912        if (ParseValueSymbolTable())
913          return true;
914        break;
915      case bitc::CONSTANTS_BLOCK_ID:
916        if (ParseConstants() || ResolveGlobalAndAliasInits())
917          return true;
918        break;
919      case bitc::FUNCTION_BLOCK_ID:
920        // If this is the first function body we've seen, reverse the
921        // FunctionsWithBodies list.
922        if (!HasReversedFunctionsWithBodies) {
923          std::reverse(FunctionsWithBodies.begin(), FunctionsWithBodies.end());
924          HasReversedFunctionsWithBodies = true;
925        }
926
927        if (RememberAndSkipFunctionBody())
928          return true;
929        break;
930      }
931      continue;
932    }
933
934    if (Code == bitc::DEFINE_ABBREV) {
935      Stream.ReadAbbrevRecord();
936      continue;
937    }
938
939    // Read a record.
940    switch (Stream.ReadRecord(Code, Record)) {
941    default: break;  // Default behavior, ignore unknown content.
942    case bitc::MODULE_CODE_VERSION:  // VERSION: [version#]
943      if (Record.size() < 1)
944        return Error("Malformed MODULE_CODE_VERSION");
945      // Only version #0 is supported so far.
946      if (Record[0] != 0)
947        return Error("Unknown bitstream version!");
948      break;
949    case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
950      std::string S;
951      if (ConvertToString(Record, 0, S))
952        return Error("Invalid MODULE_CODE_TRIPLE record");
953      TheModule->setTargetTriple(S);
954      break;
955    }
956    case bitc::MODULE_CODE_DATALAYOUT: {  // DATALAYOUT: [strchr x N]
957      std::string S;
958      if (ConvertToString(Record, 0, S))
959        return Error("Invalid MODULE_CODE_DATALAYOUT record");
960      TheModule->setDataLayout(S);
961      break;
962    }
963    case bitc::MODULE_CODE_ASM: {  // ASM: [strchr x N]
964      std::string S;
965      if (ConvertToString(Record, 0, S))
966        return Error("Invalid MODULE_CODE_ASM record");
967      TheModule->setModuleInlineAsm(S);
968      break;
969    }
970    case bitc::MODULE_CODE_DEPLIB: {  // DEPLIB: [strchr x N]
971      std::string S;
972      if (ConvertToString(Record, 0, S))
973        return Error("Invalid MODULE_CODE_DEPLIB record");
974      TheModule->addLibrary(S);
975      break;
976    }
977    case bitc::MODULE_CODE_SECTIONNAME: {  // SECTIONNAME: [strchr x N]
978      std::string S;
979      if (ConvertToString(Record, 0, S))
980        return Error("Invalid MODULE_CODE_SECTIONNAME record");
981      SectionTable.push_back(S);
982      break;
983    }
984    case bitc::MODULE_CODE_COLLECTORNAME: {  // SECTIONNAME: [strchr x N]
985      std::string S;
986      if (ConvertToString(Record, 0, S))
987        return Error("Invalid MODULE_CODE_COLLECTORNAME record");
988      CollectorTable.push_back(S);
989      break;
990    }
991    // GLOBALVAR: [pointer type, isconst, initid,
992    //             linkage, alignment, section, visibility, threadlocal]
993    case bitc::MODULE_CODE_GLOBALVAR: {
994      if (Record.size() < 6)
995        return Error("Invalid MODULE_CODE_GLOBALVAR record");
996      const Type *Ty = getTypeByID(Record[0]);
997      if (!isa<PointerType>(Ty))
998        return Error("Global not a pointer type!");
999      unsigned AddressSpace = cast<PointerType>(Ty)->getAddressSpace();
1000      Ty = cast<PointerType>(Ty)->getElementType();
1001
1002      bool isConstant = Record[1];
1003      GlobalValue::LinkageTypes Linkage = GetDecodedLinkage(Record[3]);
1004      unsigned Alignment = (1 << Record[4]) >> 1;
1005      std::string Section;
1006      if (Record[5]) {
1007        if (Record[5]-1 >= SectionTable.size())
1008          return Error("Invalid section ID");
1009        Section = SectionTable[Record[5]-1];
1010      }
1011      GlobalValue::VisibilityTypes Visibility = GlobalValue::DefaultVisibility;
1012      if (Record.size() > 6)
1013        Visibility = GetDecodedVisibility(Record[6]);
1014      bool isThreadLocal = false;
1015      if (Record.size() > 7)
1016        isThreadLocal = Record[7];
1017
1018      GlobalVariable *NewGV =
1019        new GlobalVariable(Ty, isConstant, Linkage, 0, "", TheModule,
1020                           isThreadLocal, AddressSpace);
1021      NewGV->setAlignment(Alignment);
1022      if (!Section.empty())
1023        NewGV->setSection(Section);
1024      NewGV->setVisibility(Visibility);
1025      NewGV->setThreadLocal(isThreadLocal);
1026
1027      ValueList.push_back(NewGV);
1028
1029      // Remember which value to use for the global initializer.
1030      if (unsigned InitID = Record[2])
1031        GlobalInits.push_back(std::make_pair(NewGV, InitID-1));
1032      break;
1033    }
1034    // FUNCTION:  [type, callingconv, isproto, linkage, paramattr,
1035    //             alignment, section, visibility, collector]
1036    case bitc::MODULE_CODE_FUNCTION: {
1037      if (Record.size() < 8)
1038        return Error("Invalid MODULE_CODE_FUNCTION record");
1039      const Type *Ty = getTypeByID(Record[0]);
1040      if (!isa<PointerType>(Ty))
1041        return Error("Function not a pointer type!");
1042      const FunctionType *FTy =
1043        dyn_cast<FunctionType>(cast<PointerType>(Ty)->getElementType());
1044      if (!FTy)
1045        return Error("Function not a pointer to function type!");
1046
1047      Function *Func = new Function(FTy, GlobalValue::ExternalLinkage,
1048                                    "", TheModule);
1049
1050      Func->setCallingConv(Record[1]);
1051      bool isProto = Record[2];
1052      Func->setLinkage(GetDecodedLinkage(Record[3]));
1053      const ParamAttrsList *PAL = getParamAttrs(Record[4]);
1054      Func->setParamAttrs(PAL);
1055
1056      Func->setAlignment((1 << Record[5]) >> 1);
1057      if (Record[6]) {
1058        if (Record[6]-1 >= SectionTable.size())
1059          return Error("Invalid section ID");
1060        Func->setSection(SectionTable[Record[6]-1]);
1061      }
1062      Func->setVisibility(GetDecodedVisibility(Record[7]));
1063      if (Record.size() > 8 && Record[8]) {
1064        if (Record[8]-1 > CollectorTable.size())
1065          return Error("Invalid collector ID");
1066        Func->setCollector(CollectorTable[Record[8]-1].c_str());
1067      }
1068
1069      ValueList.push_back(Func);
1070
1071      // If this is a function with a body, remember the prototype we are
1072      // creating now, so that we can match up the body with them later.
1073      if (!isProto)
1074        FunctionsWithBodies.push_back(Func);
1075      break;
1076    }
1077    // ALIAS: [alias type, aliasee val#, linkage]
1078    case bitc::MODULE_CODE_ALIAS: {
1079      if (Record.size() < 3)
1080        return Error("Invalid MODULE_ALIAS record");
1081      const Type *Ty = getTypeByID(Record[0]);
1082      if (!isa<PointerType>(Ty))
1083        return Error("Function not a pointer type!");
1084
1085      GlobalAlias *NewGA = new GlobalAlias(Ty, GetDecodedLinkage(Record[2]),
1086                                           "", 0, TheModule);
1087      ValueList.push_back(NewGA);
1088      AliasInits.push_back(std::make_pair(NewGA, Record[1]));
1089      break;
1090    }
1091    /// MODULE_CODE_PURGEVALS: [numvals]
1092    case bitc::MODULE_CODE_PURGEVALS:
1093      // Trim down the value list to the specified size.
1094      if (Record.size() < 1 || Record[0] > ValueList.size())
1095        return Error("Invalid MODULE_PURGEVALS record");
1096      ValueList.shrinkTo(Record[0]);
1097      break;
1098    }
1099    Record.clear();
1100  }
1101
1102  return Error("Premature end of bitstream");
1103}
1104
1105
1106bool BitcodeReader::ParseBitcode() {
1107  TheModule = 0;
1108
1109  if (Buffer->getBufferSize() & 3)
1110    return Error("Bitcode stream should be a multiple of 4 bytes in length");
1111
1112  unsigned char *BufPtr = (unsigned char *)Buffer->getBufferStart();
1113  Stream.init(BufPtr, BufPtr+Buffer->getBufferSize());
1114
1115  // Sniff for the signature.
1116  if (Stream.Read(8) != 'B' ||
1117      Stream.Read(8) != 'C' ||
1118      Stream.Read(4) != 0x0 ||
1119      Stream.Read(4) != 0xC ||
1120      Stream.Read(4) != 0xE ||
1121      Stream.Read(4) != 0xD)
1122    return Error("Invalid bitcode signature");
1123
1124  // We expect a number of well-defined blocks, though we don't necessarily
1125  // need to understand them all.
1126  while (!Stream.AtEndOfStream()) {
1127    unsigned Code = Stream.ReadCode();
1128
1129    if (Code != bitc::ENTER_SUBBLOCK)
1130      return Error("Invalid record at top-level");
1131
1132    unsigned BlockID = Stream.ReadSubBlockID();
1133
1134    // We only know the MODULE subblock ID.
1135    switch (BlockID) {
1136    case bitc::BLOCKINFO_BLOCK_ID:
1137      if (Stream.ReadBlockInfoBlock())
1138        return Error("Malformed BlockInfoBlock");
1139      break;
1140    case bitc::MODULE_BLOCK_ID:
1141      if (ParseModule(Buffer->getBufferIdentifier()))
1142        return true;
1143      break;
1144    default:
1145      if (Stream.SkipBlock())
1146        return Error("Malformed block record");
1147      break;
1148    }
1149  }
1150
1151  return false;
1152}
1153
1154
1155/// ParseFunctionBody - Lazily parse the specified function body block.
1156bool BitcodeReader::ParseFunctionBody(Function *F) {
1157  if (Stream.EnterSubBlock(bitc::FUNCTION_BLOCK_ID))
1158    return Error("Malformed block record");
1159
1160  unsigned ModuleValueListSize = ValueList.size();
1161
1162  // Add all the function arguments to the value table.
1163  for(Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
1164    ValueList.push_back(I);
1165
1166  unsigned NextValueNo = ValueList.size();
1167  BasicBlock *CurBB = 0;
1168  unsigned CurBBNo = 0;
1169
1170  // Read all the records.
1171  SmallVector<uint64_t, 64> Record;
1172  while (1) {
1173    unsigned Code = Stream.ReadCode();
1174    if (Code == bitc::END_BLOCK) {
1175      if (Stream.ReadBlockEnd())
1176        return Error("Error at end of function block");
1177      break;
1178    }
1179
1180    if (Code == bitc::ENTER_SUBBLOCK) {
1181      switch (Stream.ReadSubBlockID()) {
1182      default:  // Skip unknown content.
1183        if (Stream.SkipBlock())
1184          return Error("Malformed block record");
1185        break;
1186      case bitc::CONSTANTS_BLOCK_ID:
1187        if (ParseConstants()) return true;
1188        NextValueNo = ValueList.size();
1189        break;
1190      case bitc::VALUE_SYMTAB_BLOCK_ID:
1191        if (ParseValueSymbolTable()) return true;
1192        break;
1193      }
1194      continue;
1195    }
1196
1197    if (Code == bitc::DEFINE_ABBREV) {
1198      Stream.ReadAbbrevRecord();
1199      continue;
1200    }
1201
1202    // Read a record.
1203    Record.clear();
1204    Instruction *I = 0;
1205    switch (Stream.ReadRecord(Code, Record)) {
1206    default: // Default behavior: reject
1207      return Error("Unknown instruction");
1208    case bitc::FUNC_CODE_DECLAREBLOCKS:     // DECLAREBLOCKS: [nblocks]
1209      if (Record.size() < 1 || Record[0] == 0)
1210        return Error("Invalid DECLAREBLOCKS record");
1211      // Create all the basic blocks for the function.
1212      FunctionBBs.resize(Record[0]);
1213      for (unsigned i = 0, e = FunctionBBs.size(); i != e; ++i)
1214        FunctionBBs[i] = new BasicBlock("", F);
1215      CurBB = FunctionBBs[0];
1216      continue;
1217
1218    case bitc::FUNC_CODE_INST_BINOP: {    // BINOP: [opval, ty, opval, opcode]
1219      unsigned OpNum = 0;
1220      Value *LHS, *RHS;
1221      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
1222          getValue(Record, OpNum, LHS->getType(), RHS) ||
1223          OpNum+1 != Record.size())
1224        return Error("Invalid BINOP record");
1225
1226      int Opc = GetDecodedBinaryOpcode(Record[OpNum], LHS->getType());
1227      if (Opc == -1) return Error("Invalid BINOP record");
1228      I = BinaryOperator::create((Instruction::BinaryOps)Opc, LHS, RHS);
1229      break;
1230    }
1231    case bitc::FUNC_CODE_INST_CAST: {    // CAST: [opval, opty, destty, castopc]
1232      unsigned OpNum = 0;
1233      Value *Op;
1234      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
1235          OpNum+2 != Record.size())
1236        return Error("Invalid CAST record");
1237
1238      const Type *ResTy = getTypeByID(Record[OpNum]);
1239      int Opc = GetDecodedCastOpcode(Record[OpNum+1]);
1240      if (Opc == -1 || ResTy == 0)
1241        return Error("Invalid CAST record");
1242      I = CastInst::create((Instruction::CastOps)Opc, Op, ResTy);
1243      break;
1244    }
1245    case bitc::FUNC_CODE_INST_GEP: { // GEP: [n x operands]
1246      unsigned OpNum = 0;
1247      Value *BasePtr;
1248      if (getValueTypePair(Record, OpNum, NextValueNo, BasePtr))
1249        return Error("Invalid GEP record");
1250
1251      SmallVector<Value*, 16> GEPIdx;
1252      while (OpNum != Record.size()) {
1253        Value *Op;
1254        if (getValueTypePair(Record, OpNum, NextValueNo, Op))
1255          return Error("Invalid GEP record");
1256        GEPIdx.push_back(Op);
1257      }
1258
1259      I = new GetElementPtrInst(BasePtr, GEPIdx.begin(), GEPIdx.end());
1260      break;
1261    }
1262
1263    case bitc::FUNC_CODE_INST_SELECT: { // SELECT: [opval, ty, opval, opval]
1264      unsigned OpNum = 0;
1265      Value *TrueVal, *FalseVal, *Cond;
1266      if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
1267          getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
1268          getValue(Record, OpNum, Type::Int1Ty, Cond))
1269        return Error("Invalid SELECT record");
1270
1271      I = new SelectInst(Cond, TrueVal, FalseVal);
1272      break;
1273    }
1274
1275    case bitc::FUNC_CODE_INST_EXTRACTELT: { // EXTRACTELT: [opty, opval, opval]
1276      unsigned OpNum = 0;
1277      Value *Vec, *Idx;
1278      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
1279          getValue(Record, OpNum, Type::Int32Ty, Idx))
1280        return Error("Invalid EXTRACTELT record");
1281      I = new ExtractElementInst(Vec, Idx);
1282      break;
1283    }
1284
1285    case bitc::FUNC_CODE_INST_INSERTELT: { // INSERTELT: [ty, opval,opval,opval]
1286      unsigned OpNum = 0;
1287      Value *Vec, *Elt, *Idx;
1288      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
1289          getValue(Record, OpNum,
1290                   cast<VectorType>(Vec->getType())->getElementType(), Elt) ||
1291          getValue(Record, OpNum, Type::Int32Ty, Idx))
1292        return Error("Invalid INSERTELT record");
1293      I = new InsertElementInst(Vec, Elt, Idx);
1294      break;
1295    }
1296
1297    case bitc::FUNC_CODE_INST_SHUFFLEVEC: {// SHUFFLEVEC: [opval,ty,opval,opval]
1298      unsigned OpNum = 0;
1299      Value *Vec1, *Vec2, *Mask;
1300      if (getValueTypePair(Record, OpNum, NextValueNo, Vec1) ||
1301          getValue(Record, OpNum, Vec1->getType(), Vec2))
1302        return Error("Invalid SHUFFLEVEC record");
1303
1304      const Type *MaskTy =
1305        VectorType::get(Type::Int32Ty,
1306                        cast<VectorType>(Vec1->getType())->getNumElements());
1307
1308      if (getValue(Record, OpNum, MaskTy, Mask))
1309        return Error("Invalid SHUFFLEVEC record");
1310      I = new ShuffleVectorInst(Vec1, Vec2, Mask);
1311      break;
1312    }
1313
1314    case bitc::FUNC_CODE_INST_CMP: { // CMP: [opty, opval, opval, pred]
1315      unsigned OpNum = 0;
1316      Value *LHS, *RHS;
1317      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
1318          getValue(Record, OpNum, LHS->getType(), RHS) ||
1319          OpNum+1 != Record.size())
1320        return Error("Invalid CMP record");
1321
1322      if (LHS->getType()->isFPOrFPVector())
1323        I = new FCmpInst((FCmpInst::Predicate)Record[OpNum], LHS, RHS);
1324      else
1325        I = new ICmpInst((ICmpInst::Predicate)Record[OpNum], LHS, RHS);
1326      break;
1327    }
1328
1329    case bitc::FUNC_CODE_INST_RET: // RET: [opty,opval<optional>]
1330      if (Record.size() == 0) {
1331        I = new ReturnInst();
1332        break;
1333      } else {
1334        unsigned OpNum = 0;
1335        Value *Op;
1336        if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
1337            OpNum != Record.size())
1338          return Error("Invalid RET record");
1339        I = new ReturnInst(Op);
1340        break;
1341      }
1342    case bitc::FUNC_CODE_INST_BR: { // BR: [bb#, bb#, opval] or [bb#]
1343      if (Record.size() != 1 && Record.size() != 3)
1344        return Error("Invalid BR record");
1345      BasicBlock *TrueDest = getBasicBlock(Record[0]);
1346      if (TrueDest == 0)
1347        return Error("Invalid BR record");
1348
1349      if (Record.size() == 1)
1350        I = new BranchInst(TrueDest);
1351      else {
1352        BasicBlock *FalseDest = getBasicBlock(Record[1]);
1353        Value *Cond = getFnValueByID(Record[2], Type::Int1Ty);
1354        if (FalseDest == 0 || Cond == 0)
1355          return Error("Invalid BR record");
1356        I = new BranchInst(TrueDest, FalseDest, Cond);
1357      }
1358      break;
1359    }
1360    case bitc::FUNC_CODE_INST_SWITCH: { // SWITCH: [opty, opval, n, n x ops]
1361      if (Record.size() < 3 || (Record.size() & 1) == 0)
1362        return Error("Invalid SWITCH record");
1363      const Type *OpTy = getTypeByID(Record[0]);
1364      Value *Cond = getFnValueByID(Record[1], OpTy);
1365      BasicBlock *Default = getBasicBlock(Record[2]);
1366      if (OpTy == 0 || Cond == 0 || Default == 0)
1367        return Error("Invalid SWITCH record");
1368      unsigned NumCases = (Record.size()-3)/2;
1369      SwitchInst *SI = new SwitchInst(Cond, Default, NumCases);
1370      for (unsigned i = 0, e = NumCases; i != e; ++i) {
1371        ConstantInt *CaseVal =
1372          dyn_cast_or_null<ConstantInt>(getFnValueByID(Record[3+i*2], OpTy));
1373        BasicBlock *DestBB = getBasicBlock(Record[1+3+i*2]);
1374        if (CaseVal == 0 || DestBB == 0) {
1375          delete SI;
1376          return Error("Invalid SWITCH record!");
1377        }
1378        SI->addCase(CaseVal, DestBB);
1379      }
1380      I = SI;
1381      break;
1382    }
1383
1384    case bitc::FUNC_CODE_INST_INVOKE: {
1385      // INVOKE: [attrs, cc, normBB, unwindBB, fnty, op0,op1,op2, ...]
1386      if (Record.size() < 4) return Error("Invalid INVOKE record");
1387      const ParamAttrsList *PAL = getParamAttrs(Record[0]);
1388      unsigned CCInfo = Record[1];
1389      BasicBlock *NormalBB = getBasicBlock(Record[2]);
1390      BasicBlock *UnwindBB = getBasicBlock(Record[3]);
1391
1392      unsigned OpNum = 4;
1393      Value *Callee;
1394      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
1395        return Error("Invalid INVOKE record");
1396
1397      const PointerType *CalleeTy = dyn_cast<PointerType>(Callee->getType());
1398      const FunctionType *FTy = !CalleeTy ? 0 :
1399        dyn_cast<FunctionType>(CalleeTy->getElementType());
1400
1401      // Check that the right number of fixed parameters are here.
1402      if (FTy == 0 || NormalBB == 0 || UnwindBB == 0 ||
1403          Record.size() < OpNum+FTy->getNumParams())
1404        return Error("Invalid INVOKE record");
1405
1406      SmallVector<Value*, 16> Ops;
1407      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
1408        Ops.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
1409        if (Ops.back() == 0) return Error("Invalid INVOKE record");
1410      }
1411
1412      if (!FTy->isVarArg()) {
1413        if (Record.size() != OpNum)
1414          return Error("Invalid INVOKE record");
1415      } else {
1416        // Read type/value pairs for varargs params.
1417        while (OpNum != Record.size()) {
1418          Value *Op;
1419          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
1420            return Error("Invalid INVOKE record");
1421          Ops.push_back(Op);
1422        }
1423      }
1424
1425      I = new InvokeInst(Callee, NormalBB, UnwindBB, Ops.begin(), Ops.end());
1426      cast<InvokeInst>(I)->setCallingConv(CCInfo);
1427      cast<InvokeInst>(I)->setParamAttrs(PAL);
1428      break;
1429    }
1430    case bitc::FUNC_CODE_INST_UNWIND: // UNWIND
1431      I = new UnwindInst();
1432      break;
1433    case bitc::FUNC_CODE_INST_UNREACHABLE: // UNREACHABLE
1434      I = new UnreachableInst();
1435      break;
1436    case bitc::FUNC_CODE_INST_PHI: { // PHI: [ty, val0,bb0, ...]
1437      if (Record.size() < 1 || ((Record.size()-1)&1))
1438        return Error("Invalid PHI record");
1439      const Type *Ty = getTypeByID(Record[0]);
1440      if (!Ty) return Error("Invalid PHI record");
1441
1442      PHINode *PN = new PHINode(Ty);
1443      PN->reserveOperandSpace(Record.size()-1);
1444
1445      for (unsigned i = 0, e = Record.size()-1; i != e; i += 2) {
1446        Value *V = getFnValueByID(Record[1+i], Ty);
1447        BasicBlock *BB = getBasicBlock(Record[2+i]);
1448        if (!V || !BB) return Error("Invalid PHI record");
1449        PN->addIncoming(V, BB);
1450      }
1451      I = PN;
1452      break;
1453    }
1454
1455    case bitc::FUNC_CODE_INST_MALLOC: { // MALLOC: [instty, op, align]
1456      if (Record.size() < 3)
1457        return Error("Invalid MALLOC record");
1458      const PointerType *Ty =
1459        dyn_cast_or_null<PointerType>(getTypeByID(Record[0]));
1460      Value *Size = getFnValueByID(Record[1], Type::Int32Ty);
1461      unsigned Align = Record[2];
1462      if (!Ty || !Size) return Error("Invalid MALLOC record");
1463      I = new MallocInst(Ty->getElementType(), Size, (1 << Align) >> 1);
1464      break;
1465    }
1466    case bitc::FUNC_CODE_INST_FREE: { // FREE: [op, opty]
1467      unsigned OpNum = 0;
1468      Value *Op;
1469      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
1470          OpNum != Record.size())
1471        return Error("Invalid FREE record");
1472      I = new FreeInst(Op);
1473      break;
1474    }
1475    case bitc::FUNC_CODE_INST_ALLOCA: { // ALLOCA: [instty, op, align]
1476      if (Record.size() < 3)
1477        return Error("Invalid ALLOCA record");
1478      const PointerType *Ty =
1479        dyn_cast_or_null<PointerType>(getTypeByID(Record[0]));
1480      Value *Size = getFnValueByID(Record[1], Type::Int32Ty);
1481      unsigned Align = Record[2];
1482      if (!Ty || !Size) return Error("Invalid ALLOCA record");
1483      I = new AllocaInst(Ty->getElementType(), Size, (1 << Align) >> 1);
1484      break;
1485    }
1486    case bitc::FUNC_CODE_INST_LOAD: { // LOAD: [opty, op, align, vol]
1487      unsigned OpNum = 0;
1488      Value *Op;
1489      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
1490          OpNum+2 != Record.size())
1491        return Error("Invalid LOAD record");
1492
1493      I = new LoadInst(Op, "", Record[OpNum+1], (1 << Record[OpNum]) >> 1);
1494      break;
1495    }
1496    case bitc::FUNC_CODE_INST_STORE2: { // STORE2:[ptrty, ptr, val, align, vol]
1497      unsigned OpNum = 0;
1498      Value *Val, *Ptr;
1499      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
1500          getValue(Record, OpNum,
1501                    cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
1502          OpNum+2 != Record.size())
1503        return Error("Invalid STORE record");
1504
1505      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1);
1506      break;
1507    }
1508    case bitc::FUNC_CODE_INST_STORE: { // STORE:[val, valty, ptr, align, vol]
1509      // FIXME: Legacy form of store instruction. Should be removed in LLVM 3.0.
1510      unsigned OpNum = 0;
1511      Value *Val, *Ptr;
1512      if (getValueTypePair(Record, OpNum, NextValueNo, Val) ||
1513          getValue(Record, OpNum, PointerType::getUnqual(Val->getType()), Ptr)||
1514          OpNum+2 != Record.size())
1515        return Error("Invalid STORE record");
1516
1517      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1);
1518      break;
1519    }
1520    case bitc::FUNC_CODE_INST_CALL: {
1521      // CALL: [paramattrs, cc, fnty, fnid, arg0, arg1...]
1522      if (Record.size() < 3)
1523        return Error("Invalid CALL record");
1524
1525      const ParamAttrsList *PAL = getParamAttrs(Record[0]);
1526      unsigned CCInfo = Record[1];
1527
1528      unsigned OpNum = 2;
1529      Value *Callee;
1530      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
1531        return Error("Invalid CALL record");
1532
1533      const PointerType *OpTy = dyn_cast<PointerType>(Callee->getType());
1534      const FunctionType *FTy = 0;
1535      if (OpTy) FTy = dyn_cast<FunctionType>(OpTy->getElementType());
1536      if (!FTy || Record.size() < FTy->getNumParams()+OpNum)
1537        return Error("Invalid CALL record");
1538
1539      SmallVector<Value*, 16> Args;
1540      // Read the fixed params.
1541      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
1542        if (FTy->getParamType(i)->getTypeID()==Type::LabelTyID)
1543          Args.push_back(getBasicBlock(Record[OpNum]));
1544        else
1545          Args.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
1546        if (Args.back() == 0) return Error("Invalid CALL record");
1547      }
1548
1549      // Read type/value pairs for varargs params.
1550      if (!FTy->isVarArg()) {
1551        if (OpNum != Record.size())
1552          return Error("Invalid CALL record");
1553      } else {
1554        while (OpNum != Record.size()) {
1555          Value *Op;
1556          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
1557            return Error("Invalid CALL record");
1558          Args.push_back(Op);
1559        }
1560      }
1561
1562      I = new CallInst(Callee, Args.begin(), Args.end());
1563      cast<CallInst>(I)->setCallingConv(CCInfo>>1);
1564      cast<CallInst>(I)->setTailCall(CCInfo & 1);
1565      cast<CallInst>(I)->setParamAttrs(PAL);
1566      break;
1567    }
1568    case bitc::FUNC_CODE_INST_VAARG: { // VAARG: [valistty, valist, instty]
1569      if (Record.size() < 3)
1570        return Error("Invalid VAARG record");
1571      const Type *OpTy = getTypeByID(Record[0]);
1572      Value *Op = getFnValueByID(Record[1], OpTy);
1573      const Type *ResTy = getTypeByID(Record[2]);
1574      if (!OpTy || !Op || !ResTy)
1575        return Error("Invalid VAARG record");
1576      I = new VAArgInst(Op, ResTy);
1577      break;
1578    }
1579    }
1580
1581    // Add instruction to end of current BB.  If there is no current BB, reject
1582    // this file.
1583    if (CurBB == 0) {
1584      delete I;
1585      return Error("Invalid instruction with no BB");
1586    }
1587    CurBB->getInstList().push_back(I);
1588
1589    // If this was a terminator instruction, move to the next block.
1590    if (isa<TerminatorInst>(I)) {
1591      ++CurBBNo;
1592      CurBB = CurBBNo < FunctionBBs.size() ? FunctionBBs[CurBBNo] : 0;
1593    }
1594
1595    // Non-void values get registered in the value table for future use.
1596    if (I && I->getType() != Type::VoidTy)
1597      ValueList.AssignValue(I, NextValueNo++);
1598  }
1599
1600  // Check the function list for unresolved values.
1601  if (Argument *A = dyn_cast<Argument>(ValueList.back())) {
1602    if (A->getParent() == 0) {
1603      // We found at least one unresolved value.  Nuke them all to avoid leaks.
1604      for (unsigned i = ModuleValueListSize, e = ValueList.size(); i != e; ++i){
1605        if ((A = dyn_cast<Argument>(ValueList.back())) && A->getParent() == 0) {
1606          A->replaceAllUsesWith(UndefValue::get(A->getType()));
1607          delete A;
1608        }
1609      }
1610      return Error("Never resolved value found in function!");
1611    }
1612  }
1613
1614  // Trim the value list down to the size it was before we parsed this function.
1615  ValueList.shrinkTo(ModuleValueListSize);
1616  std::vector<BasicBlock*>().swap(FunctionBBs);
1617
1618  return false;
1619}
1620
1621//===----------------------------------------------------------------------===//
1622// ModuleProvider implementation
1623//===----------------------------------------------------------------------===//
1624
1625
1626bool BitcodeReader::materializeFunction(Function *F, std::string *ErrInfo) {
1627  // If it already is material, ignore the request.
1628  if (!F->hasNotBeenReadFromBitcode()) return false;
1629
1630  DenseMap<Function*, std::pair<uint64_t, unsigned> >::iterator DFII =
1631    DeferredFunctionInfo.find(F);
1632  assert(DFII != DeferredFunctionInfo.end() && "Deferred function not found!");
1633
1634  // Move the bit stream to the saved position of the deferred function body and
1635  // restore the real linkage type for the function.
1636  Stream.JumpToBit(DFII->second.first);
1637  F->setLinkage((GlobalValue::LinkageTypes)DFII->second.second);
1638
1639  if (ParseFunctionBody(F)) {
1640    if (ErrInfo) *ErrInfo = ErrorString;
1641    return true;
1642  }
1643
1644  // Upgrade any old intrinsic calls in the function.
1645  for (UpgradedIntrinsicMap::iterator I = UpgradedIntrinsics.begin(),
1646       E = UpgradedIntrinsics.end(); I != E; ++I) {
1647    if (I->first != I->second) {
1648      for (Value::use_iterator UI = I->first->use_begin(),
1649           UE = I->first->use_end(); UI != UE; ) {
1650        if (CallInst* CI = dyn_cast<CallInst>(*UI++))
1651          UpgradeIntrinsicCall(CI, I->second);
1652      }
1653    }
1654  }
1655
1656  return false;
1657}
1658
1659void BitcodeReader::dematerializeFunction(Function *F) {
1660  // If this function isn't materialized, or if it is a proto, this is a noop.
1661  if (F->hasNotBeenReadFromBitcode() || F->isDeclaration())
1662    return;
1663
1664  assert(DeferredFunctionInfo.count(F) && "No info to read function later?");
1665
1666  // Just forget the function body, we can remat it later.
1667  F->deleteBody();
1668  F->setLinkage(GlobalValue::GhostLinkage);
1669}
1670
1671
1672Module *BitcodeReader::materializeModule(std::string *ErrInfo) {
1673  for (DenseMap<Function*, std::pair<uint64_t, unsigned> >::iterator I =
1674       DeferredFunctionInfo.begin(), E = DeferredFunctionInfo.end(); I != E;
1675       ++I) {
1676    Function *F = I->first;
1677    if (F->hasNotBeenReadFromBitcode() &&
1678        materializeFunction(F, ErrInfo))
1679      return 0;
1680  }
1681
1682  // Upgrade any intrinsic calls that slipped through (should not happen!) and
1683  // delete the old functions to clean up. We can't do this unless the entire
1684  // module is materialized because there could always be another function body
1685  // with calls to the old function.
1686  for (std::vector<std::pair<Function*, Function*> >::iterator I =
1687       UpgradedIntrinsics.begin(), E = UpgradedIntrinsics.end(); I != E; ++I) {
1688    if (I->first != I->second) {
1689      for (Value::use_iterator UI = I->first->use_begin(),
1690           UE = I->first->use_end(); UI != UE; ) {
1691        if (CallInst* CI = dyn_cast<CallInst>(*UI++))
1692          UpgradeIntrinsicCall(CI, I->second);
1693      }
1694      ValueList.replaceUsesOfWith(I->first, I->second);
1695      I->first->eraseFromParent();
1696    }
1697  }
1698  std::vector<std::pair<Function*, Function*> >().swap(UpgradedIntrinsics);
1699
1700  return TheModule;
1701}
1702
1703
1704/// This method is provided by the parent ModuleProvde class and overriden
1705/// here. It simply releases the module from its provided and frees up our
1706/// state.
1707/// @brief Release our hold on the generated module
1708Module *BitcodeReader::releaseModule(std::string *ErrInfo) {
1709  // Since we're losing control of this Module, we must hand it back complete
1710  Module *M = ModuleProvider::releaseModule(ErrInfo);
1711  FreeState();
1712  return M;
1713}
1714
1715
1716//===----------------------------------------------------------------------===//
1717// External interface
1718//===----------------------------------------------------------------------===//
1719
1720/// getBitcodeModuleProvider - lazy function-at-a-time loading from a file.
1721///
1722ModuleProvider *llvm::getBitcodeModuleProvider(MemoryBuffer *Buffer,
1723                                               std::string *ErrMsg) {
1724  BitcodeReader *R = new BitcodeReader(Buffer);
1725  if (R->ParseBitcode()) {
1726    if (ErrMsg)
1727      *ErrMsg = R->getErrorString();
1728
1729    // Don't let the BitcodeReader dtor delete 'Buffer'.
1730    R->releaseMemoryBuffer();
1731    delete R;
1732    return 0;
1733  }
1734  return R;
1735}
1736
1737/// ParseBitcodeFile - Read the specified bitcode file, returning the module.
1738/// If an error occurs, return null and fill in *ErrMsg if non-null.
1739Module *llvm::ParseBitcodeFile(MemoryBuffer *Buffer, std::string *ErrMsg){
1740  BitcodeReader *R;
1741  R = static_cast<BitcodeReader*>(getBitcodeModuleProvider(Buffer, ErrMsg));
1742  if (!R) return 0;
1743
1744  // Read in the entire module.
1745  Module *M = R->materializeModule(ErrMsg);
1746
1747  // Don't let the BitcodeReader dtor delete 'Buffer', regardless of whether
1748  // there was an error.
1749  R->releaseMemoryBuffer();
1750
1751  // If there was no error, tell ModuleProvider not to delete it when its dtor
1752  // is run.
1753  if (M)
1754    M = R->releaseModule(ErrMsg);
1755
1756  delete R;
1757  return M;
1758}
1759