BitcodeReader.cpp revision 461edd937e9ec95193022629314c66d2c1e984d2 
1//===- BitcodeReader.cpp - Internal BitcodeReader implementation ----------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// 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/ParamAttrsList.h"
22#include "llvm/AutoUpgrade.h"
23#include "llvm/ADT/SmallString.h"
24#include "llvm/ADT/SmallVector.h"
25#include "llvm/Support/MathExtras.h"
26#include "llvm/Support/MemoryBuffer.h"
27using namespace llvm;
28
29void BitcodeReader::FreeState() {
30  delete Buffer;
31  Buffer = 0;
32  std::vector<PATypeHolder>().swap(TypeList);
33  ValueList.clear();
34
35  // Drop references to ParamAttrs.
36  for (unsigned i = 0, e = ParamAttrs.size(); i != e; ++i)
37    ParamAttrs[i]->dropRef();
38
39  std::vector<const ParamAttrsList*>().swap(ParamAttrs);
40  std::vector<BasicBlock*>().swap(FunctionBBs);
41  std::vector<Function*>().swap(FunctionsWithBodies);
42  DeferredFunctionInfo.clear();
43}
44
45//===----------------------------------------------------------------------===//
46//  Helper functions to implement forward reference resolution, etc.
47//===----------------------------------------------------------------------===//
48
49/// ConvertToString - Convert a string from a record into an std::string, return
50/// true on failure.
51template<typename StrTy>
52static bool ConvertToString(SmallVector<uint64_t, 64> &Record, unsigned Idx,
53                            StrTy &Result) {
54  if (Idx > Record.size())
55    return true;
56
57  for (unsigned i = Idx, e = Record.size(); i != e; ++i)
58    Result += (char)Record[i];
59  return false;
60}
61
62static GlobalValue::LinkageTypes GetDecodedLinkage(unsigned Val) {
63  switch (Val) {
64  default: // Map unknown/new linkages to external
65  case 0: return GlobalValue::ExternalLinkage;
66  case 1: return GlobalValue::WeakLinkage;
67  case 2: return GlobalValue::AppendingLinkage;
68  case 3: return GlobalValue::InternalLinkage;
69  case 4: return GlobalValue::LinkOnceLinkage;
70  case 5: return GlobalValue::DLLImportLinkage;
71  case 6: return GlobalValue::DLLExportLinkage;
72  case 7: return GlobalValue::ExternalWeakLinkage;
73  }
74}
75
76static GlobalValue::VisibilityTypes GetDecodedVisibility(unsigned Val) {
77  switch (Val) {
78  default: // Map unknown visibilities to default.
79  case 0: return GlobalValue::DefaultVisibility;
80  case 1: return GlobalValue::HiddenVisibility;
81  case 2: return GlobalValue::ProtectedVisibility;
82  }
83}
84
85static int GetDecodedCastOpcode(unsigned Val) {
86  switch (Val) {
87  default: return -1;
88  case bitc::CAST_TRUNC   : return Instruction::Trunc;
89  case bitc::CAST_ZEXT    : return Instruction::ZExt;
90  case bitc::CAST_SEXT    : return Instruction::SExt;
91  case bitc::CAST_FPTOUI  : return Instruction::FPToUI;
92  case bitc::CAST_FPTOSI  : return Instruction::FPToSI;
93  case bitc::CAST_UITOFP  : return Instruction::UIToFP;
94  case bitc::CAST_SITOFP  : return Instruction::SIToFP;
95  case bitc::CAST_FPTRUNC : return Instruction::FPTrunc;
96  case bitc::CAST_FPEXT   : return Instruction::FPExt;
97  case bitc::CAST_PTRTOINT: return Instruction::PtrToInt;
98  case bitc::CAST_INTTOPTR: return Instruction::IntToPtr;
99  case bitc::CAST_BITCAST : return Instruction::BitCast;
100  }
101}
102static int GetDecodedBinaryOpcode(unsigned Val, const Type *Ty) {
103  switch (Val) {
104  default: return -1;
105  case bitc::BINOP_ADD:  return Instruction::Add;
106  case bitc::BINOP_SUB:  return Instruction::Sub;
107  case bitc::BINOP_MUL:  return Instruction::Mul;
108  case bitc::BINOP_UDIV: return Instruction::UDiv;
109  case bitc::BINOP_SDIV:
110    return Ty->isFPOrFPVector() ? Instruction::FDiv : Instruction::SDiv;
111  case bitc::BINOP_UREM: return Instruction::URem;
112  case bitc::BINOP_SREM:
113    return Ty->isFPOrFPVector() ? Instruction::FRem : Instruction::SRem;
114  case bitc::BINOP_SHL:  return Instruction::Shl;
115  case bitc::BINOP_LSHR: return Instruction::LShr;
116  case bitc::BINOP_ASHR: return Instruction::AShr;
117  case bitc::BINOP_AND:  return Instruction::And;
118  case bitc::BINOP_OR:   return Instruction::Or;
119  case bitc::BINOP_XOR:  return Instruction::Xor;
120  }
121}
122
123
124namespace {
125  /// @brief A class for maintaining the slot number definition
126  /// as a placeholder for the actual definition for forward constants defs.
127  class ConstantPlaceHolder : public ConstantExpr {
128    ConstantPlaceHolder();                       // DO NOT IMPLEMENT
129    void operator=(const ConstantPlaceHolder &); // DO NOT IMPLEMENT
130  public:
131    Use Op;
132    explicit ConstantPlaceHolder(const Type *Ty)
133      : ConstantExpr(Ty, Instruction::UserOp1, &Op, 1),
134        Op(UndefValue::get(Type::Int32Ty), this) {
135    }
136  };
137}
138
139Constant *BitcodeReaderValueList::getConstantFwdRef(unsigned Idx,
140                                                    const Type *Ty) {
141  if (Idx >= size()) {
142    // Insert a bunch of null values.
143    Uses.resize(Idx+1);
144    OperandList = &Uses[0];
145    NumOperands = Idx+1;
146  }
147
148  if (Value *V = Uses[Idx]) {
149    assert(Ty == V->getType() && "Type mismatch in constant table!");
150    return cast<Constant>(V);
151  }
152
153  // Create and return a placeholder, which will later be RAUW'd.
154  Constant *C = new ConstantPlaceHolder(Ty);
155  Uses[Idx].init(C, this);
156  return C;
157}
158
159Value *BitcodeReaderValueList::getValueFwdRef(unsigned Idx, const Type *Ty) {
160  if (Idx >= size()) {
161    // Insert a bunch of null values.
162    Uses.resize(Idx+1);
163    OperandList = &Uses[0];
164    NumOperands = Idx+1;
165  }
166
167  if (Value *V = Uses[Idx]) {
168    assert((Ty == 0 || Ty == V->getType()) && "Type mismatch in value table!");
169    return V;
170  }
171
172  // No type specified, must be invalid reference.
173  if (Ty == 0) return 0;
174
175  // Create and return a placeholder, which will later be RAUW'd.
176  Value *V = new Argument(Ty);
177  Uses[Idx].init(V, this);
178  return V;
179}
180
181
182const Type *BitcodeReader::getTypeByID(unsigned ID, bool isTypeTable) {
183  // If the TypeID is in range, return it.
184  if (ID < TypeList.size())
185    return TypeList[ID].get();
186  if (!isTypeTable) return 0;
187
188  // The type table allows forward references.  Push as many Opaque types as
189  // needed to get up to ID.
190  while (TypeList.size() <= ID)
191    TypeList.push_back(OpaqueType::get());
192  return TypeList.back().get();
193}
194
195//===----------------------------------------------------------------------===//
196//  Functions for parsing blocks from the bitcode file
197//===----------------------------------------------------------------------===//
198
199bool BitcodeReader::ParseParamAttrBlock() {
200  if (Stream.EnterSubBlock(bitc::PARAMATTR_BLOCK_ID))
201    return Error("Malformed block record");
202
203  if (!ParamAttrs.empty())
204    return Error("Multiple PARAMATTR blocks found!");
205
206  SmallVector<uint64_t, 64> Record;
207
208  ParamAttrsVector Attrs;
209
210  // Read all the records.
211  while (1) {
212    unsigned Code = Stream.ReadCode();
213    if (Code == bitc::END_BLOCK) {
214      if (Stream.ReadBlockEnd())
215        return Error("Error at end of PARAMATTR block");
216      return false;
217    }
218
219    if (Code == bitc::ENTER_SUBBLOCK) {
220      // No known subblocks, always skip them.
221      Stream.ReadSubBlockID();
222      if (Stream.SkipBlock())
223        return Error("Malformed block record");
224      continue;
225    }
226
227    if (Code == bitc::DEFINE_ABBREV) {
228      Stream.ReadAbbrevRecord();
229      continue;
230    }
231
232    // Read a record.
233    Record.clear();
234    switch (Stream.ReadRecord(Code, Record)) {
235    default:  // Default behavior: ignore.
236      break;
237    case bitc::PARAMATTR_CODE_ENTRY: { // ENTRY: [paramidx0, attr0, ...]
238      if (Record.size() & 1)
239        return Error("Invalid ENTRY record");
240
241      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
242        if (Record[i+1] != ParamAttr::None)
243          Attrs.push_back(ParamAttrsWithIndex::get(Record[i], Record[i+1]));
244      }
245      if (Attrs.empty()) {
246        ParamAttrs.push_back(0);
247      } else {
248        ParamAttrs.push_back(ParamAttrsList::get(Attrs));
249        ParamAttrs.back()->addRef();
250      }
251
252      Attrs.clear();
253      break;
254    }
255    }
256  }
257}
258
259
260bool BitcodeReader::ParseTypeTable() {
261  if (Stream.EnterSubBlock(bitc::TYPE_BLOCK_ID))
262    return Error("Malformed block record");
263
264  if (!TypeList.empty())
265    return Error("Multiple TYPE_BLOCKs found!");
266
267  SmallVector<uint64_t, 64> Record;
268  unsigned NumRecords = 0;
269
270  // Read all the records for this type table.
271  while (1) {
272    unsigned Code = Stream.ReadCode();
273    if (Code == bitc::END_BLOCK) {
274      if (NumRecords != TypeList.size())
275        return Error("Invalid type forward reference in TYPE_BLOCK");
276      if (Stream.ReadBlockEnd())
277        return Error("Error at end of type table block");
278      return false;
279    }
280
281    if (Code == bitc::ENTER_SUBBLOCK) {
282      // No known subblocks, always skip them.
283      Stream.ReadSubBlockID();
284      if (Stream.SkipBlock())
285        return Error("Malformed block record");
286      continue;
287    }
288
289    if (Code == bitc::DEFINE_ABBREV) {
290      Stream.ReadAbbrevRecord();
291      continue;
292    }
293
294    // Read a record.
295    Record.clear();
296    const Type *ResultTy = 0;
297    switch (Stream.ReadRecord(Code, Record)) {
298    default:  // Default behavior: unknown type.
299      ResultTy = 0;
300      break;
301    case bitc::TYPE_CODE_NUMENTRY: // TYPE_CODE_NUMENTRY: [numentries]
302      // TYPE_CODE_NUMENTRY contains a count of the number of types in the
303      // type list.  This allows us to reserve space.
304      if (Record.size() < 1)
305        return Error("Invalid TYPE_CODE_NUMENTRY record");
306      TypeList.reserve(Record[0]);
307      continue;
308    case bitc::TYPE_CODE_VOID:      // VOID
309      ResultTy = Type::VoidTy;
310      break;
311    case bitc::TYPE_CODE_FLOAT:     // FLOAT
312      ResultTy = Type::FloatTy;
313      break;
314    case bitc::TYPE_CODE_DOUBLE:    // DOUBLE
315      ResultTy = Type::DoubleTy;
316      break;
317    case bitc::TYPE_CODE_X86_FP80:  // X86_FP80
318      ResultTy = Type::X86_FP80Ty;
319      break;
320    case bitc::TYPE_CODE_FP128:     // FP128
321      ResultTy = Type::FP128Ty;
322      break;
323    case bitc::TYPE_CODE_PPC_FP128: // PPC_FP128
324      ResultTy = Type::PPC_FP128Ty;
325      break;
326    case bitc::TYPE_CODE_LABEL:     // LABEL
327      ResultTy = Type::LabelTy;
328      break;
329    case bitc::TYPE_CODE_OPAQUE:    // OPAQUE
330      ResultTy = 0;
331      break;
332    case bitc::TYPE_CODE_INTEGER:   // INTEGER: [width]
333      if (Record.size() < 1)
334        return Error("Invalid Integer type record");
335
336      ResultTy = IntegerType::get(Record[0]);
337      break;
338    case bitc::TYPE_CODE_POINTER: { // POINTER: [pointee type] or
339                                    //          [pointee type, address space]
340      if (Record.size() < 1)
341        return Error("Invalid POINTER type record");
342      unsigned AddressSpace = 0;
343      if (Record.size() == 2)
344        AddressSpace = Record[1];
345      ResultTy = PointerType::get(getTypeByID(Record[0], true), AddressSpace);
346      break;
347    }
348    case bitc::TYPE_CODE_FUNCTION: {
349      // FIXME: attrid is dead, remove it in LLVM 3.0
350      // FUNCTION: [vararg, attrid, retty, paramty x N]
351      if (Record.size() < 3)
352        return Error("Invalid FUNCTION type record");
353      std::vector<const Type*> ArgTys;
354      for (unsigned i = 3, e = Record.size(); i != e; ++i)
355        ArgTys.push_back(getTypeByID(Record[i], true));
356
357      ResultTy = FunctionType::get(getTypeByID(Record[2], true), ArgTys,
358                                   Record[0]);
359      break;
360    }
361    case bitc::TYPE_CODE_STRUCT: {  // STRUCT: [ispacked, eltty x N]
362      if (Record.size() < 1)
363        return Error("Invalid STRUCT type record");
364      std::vector<const Type*> EltTys;
365      for (unsigned i = 1, e = Record.size(); i != e; ++i)
366        EltTys.push_back(getTypeByID(Record[i], true));
367      ResultTy = StructType::get(EltTys, Record[0]);
368      break;
369    }
370    case bitc::TYPE_CODE_ARRAY:     // ARRAY: [numelts, eltty]
371      if (Record.size() < 2)
372        return Error("Invalid ARRAY type record");
373      ResultTy = ArrayType::get(getTypeByID(Record[1], true), Record[0]);
374      break;
375    case bitc::TYPE_CODE_VECTOR:    // VECTOR: [numelts, eltty]
376      if (Record.size() < 2)
377        return Error("Invalid VECTOR type record");
378      ResultTy = VectorType::get(getTypeByID(Record[1], true), Record[0]);
379      break;
380    }
381
382    if (NumRecords == TypeList.size()) {
383      // If this is a new type slot, just append it.
384      TypeList.push_back(ResultTy ? ResultTy : OpaqueType::get());
385      ++NumRecords;
386    } else if (ResultTy == 0) {
387      // Otherwise, this was forward referenced, so an opaque type was created,
388      // but the result type is actually just an opaque.  Leave the one we
389      // created previously.
390      ++NumRecords;
391    } else {
392      // Otherwise, this was forward referenced, so an opaque type was created.
393      // Resolve the opaque type to the real type now.
394      assert(NumRecords < TypeList.size() && "Typelist imbalance");
395      const OpaqueType *OldTy = cast<OpaqueType>(TypeList[NumRecords++].get());
396
397      // Don't directly push the new type on the Tab. Instead we want to replace
398      // the opaque type we previously inserted with the new concrete value. The
399      // refinement from the abstract (opaque) type to the new type causes all
400      // uses of the abstract type to use the concrete type (NewTy). This will
401      // also cause the opaque type to be deleted.
402      const_cast<OpaqueType*>(OldTy)->refineAbstractTypeTo(ResultTy);
403
404      // This should have replaced the old opaque type with the new type in the
405      // value table... or with a preexisting type that was already in the
406      // system.  Let's just make sure it did.
407      assert(TypeList[NumRecords-1].get() != OldTy &&
408             "refineAbstractType didn't work!");
409    }
410  }
411}
412
413
414bool BitcodeReader::ParseTypeSymbolTable() {
415  if (Stream.EnterSubBlock(bitc::TYPE_SYMTAB_BLOCK_ID))
416    return Error("Malformed block record");
417
418  SmallVector<uint64_t, 64> Record;
419
420  // Read all the records for this type table.
421  std::string TypeName;
422  while (1) {
423    unsigned Code = Stream.ReadCode();
424    if (Code == bitc::END_BLOCK) {
425      if (Stream.ReadBlockEnd())
426        return Error("Error at end of type symbol table block");
427      return false;
428    }
429
430    if (Code == bitc::ENTER_SUBBLOCK) {
431      // No known subblocks, always skip them.
432      Stream.ReadSubBlockID();
433      if (Stream.SkipBlock())
434        return Error("Malformed block record");
435      continue;
436    }
437
438    if (Code == bitc::DEFINE_ABBREV) {
439      Stream.ReadAbbrevRecord();
440      continue;
441    }
442
443    // Read a record.
444    Record.clear();
445    switch (Stream.ReadRecord(Code, Record)) {
446    default:  // Default behavior: unknown type.
447      break;
448    case bitc::TST_CODE_ENTRY:    // TST_ENTRY: [typeid, namechar x N]
449      if (ConvertToString(Record, 1, TypeName))
450        return Error("Invalid TST_ENTRY record");
451      unsigned TypeID = Record[0];
452      if (TypeID >= TypeList.size())
453        return Error("Invalid Type ID in TST_ENTRY record");
454
455      TheModule->addTypeName(TypeName, TypeList[TypeID].get());
456      TypeName.clear();
457      break;
458    }
459  }
460}
461
462bool BitcodeReader::ParseValueSymbolTable() {
463  if (Stream.EnterSubBlock(bitc::VALUE_SYMTAB_BLOCK_ID))
464    return Error("Malformed block record");
465
466  SmallVector<uint64_t, 64> Record;
467
468  // Read all the records for this value table.
469  SmallString<128> ValueName;
470  while (1) {
471    unsigned Code = Stream.ReadCode();
472    if (Code == bitc::END_BLOCK) {
473      if (Stream.ReadBlockEnd())
474        return Error("Error at end of value symbol table block");
475      return false;
476    }
477    if (Code == bitc::ENTER_SUBBLOCK) {
478      // No known subblocks, always skip them.
479      Stream.ReadSubBlockID();
480      if (Stream.SkipBlock())
481        return Error("Malformed block record");
482      continue;
483    }
484
485    if (Code == bitc::DEFINE_ABBREV) {
486      Stream.ReadAbbrevRecord();
487      continue;
488    }
489
490    // Read a record.
491    Record.clear();
492    switch (Stream.ReadRecord(Code, Record)) {
493    default:  // Default behavior: unknown type.
494      break;
495    case bitc::VST_CODE_ENTRY: {  // VST_ENTRY: [valueid, namechar x N]
496      if (ConvertToString(Record, 1, ValueName))
497        return Error("Invalid TST_ENTRY record");
498      unsigned ValueID = Record[0];
499      if (ValueID >= ValueList.size())
500        return Error("Invalid Value ID in VST_ENTRY record");
501      Value *V = ValueList[ValueID];
502
503      V->setName(&ValueName[0], ValueName.size());
504      ValueName.clear();
505      break;
506    }
507    case bitc::VST_CODE_BBENTRY: {
508      if (ConvertToString(Record, 1, ValueName))
509        return Error("Invalid VST_BBENTRY record");
510      BasicBlock *BB = getBasicBlock(Record[0]);
511      if (BB == 0)
512        return Error("Invalid BB ID in VST_BBENTRY record");
513
514      BB->setName(&ValueName[0], ValueName.size());
515      ValueName.clear();
516      break;
517    }
518    }
519  }
520}
521
522/// DecodeSignRotatedValue - Decode a signed value stored with the sign bit in
523/// the LSB for dense VBR encoding.
524static uint64_t DecodeSignRotatedValue(uint64_t V) {
525  if ((V & 1) == 0)
526    return V >> 1;
527  if (V != 1)
528    return -(V >> 1);
529  // There is no such thing as -0 with integers.  "-0" really means MININT.
530  return 1ULL << 63;
531}
532
533/// ResolveGlobalAndAliasInits - Resolve all of the initializers for global
534/// values and aliases that we can.
535bool BitcodeReader::ResolveGlobalAndAliasInits() {
536  std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInitWorklist;
537  std::vector<std::pair<GlobalAlias*, unsigned> > AliasInitWorklist;
538
539  GlobalInitWorklist.swap(GlobalInits);
540  AliasInitWorklist.swap(AliasInits);
541
542  while (!GlobalInitWorklist.empty()) {
543    unsigned ValID = GlobalInitWorklist.back().second;
544    if (ValID >= ValueList.size()) {
545      // Not ready to resolve this yet, it requires something later in the file.
546      GlobalInits.push_back(GlobalInitWorklist.back());
547    } else {
548      if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
549        GlobalInitWorklist.back().first->setInitializer(C);
550      else
551        return Error("Global variable initializer is not a constant!");
552    }
553    GlobalInitWorklist.pop_back();
554  }
555
556  while (!AliasInitWorklist.empty()) {
557    unsigned ValID = AliasInitWorklist.back().second;
558    if (ValID >= ValueList.size()) {
559      AliasInits.push_back(AliasInitWorklist.back());
560    } else {
561      if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
562        AliasInitWorklist.back().first->setAliasee(C);
563      else
564        return Error("Alias initializer is not a constant!");
565    }
566    AliasInitWorklist.pop_back();
567  }
568  return false;
569}
570
571
572bool BitcodeReader::ParseConstants() {
573  if (Stream.EnterSubBlock(bitc::CONSTANTS_BLOCK_ID))
574    return Error("Malformed block record");
575
576  SmallVector<uint64_t, 64> Record;
577
578  // Read all the records for this value table.
579  const Type *CurTy = Type::Int32Ty;
580  unsigned NextCstNo = ValueList.size();
581  while (1) {
582    unsigned Code = Stream.ReadCode();
583    if (Code == bitc::END_BLOCK) {
584      if (NextCstNo != ValueList.size())
585        return Error("Invalid constant reference!");
586
587      if (Stream.ReadBlockEnd())
588        return Error("Error at end of constants block");
589      return false;
590    }
591
592    if (Code == bitc::ENTER_SUBBLOCK) {
593      // No known subblocks, always skip them.
594      Stream.ReadSubBlockID();
595      if (Stream.SkipBlock())
596        return Error("Malformed block record");
597      continue;
598    }
599
600    if (Code == bitc::DEFINE_ABBREV) {
601      Stream.ReadAbbrevRecord();
602      continue;
603    }
604
605    // Read a record.
606    Record.clear();
607    Value *V = 0;
608    switch (Stream.ReadRecord(Code, Record)) {
609    default:  // Default behavior: unknown constant
610    case bitc::CST_CODE_UNDEF:     // UNDEF
611      V = UndefValue::get(CurTy);
612      break;
613    case bitc::CST_CODE_SETTYPE:   // SETTYPE: [typeid]
614      if (Record.empty())
615        return Error("Malformed CST_SETTYPE record");
616      if (Record[0] >= TypeList.size())
617        return Error("Invalid Type ID in CST_SETTYPE record");
618      CurTy = TypeList[Record[0]];
619      continue;  // Skip the ValueList manipulation.
620    case bitc::CST_CODE_NULL:      // NULL
621      V = Constant::getNullValue(CurTy);
622      break;
623    case bitc::CST_CODE_INTEGER:   // INTEGER: [intval]
624      if (!isa<IntegerType>(CurTy) || Record.empty())
625        return Error("Invalid CST_INTEGER record");
626      V = ConstantInt::get(CurTy, DecodeSignRotatedValue(Record[0]));
627      break;
628    case bitc::CST_CODE_WIDE_INTEGER: {// WIDE_INTEGER: [n x intval]
629      if (!isa<IntegerType>(CurTy) || Record.empty())
630        return Error("Invalid WIDE_INTEGER record");
631
632      unsigned NumWords = Record.size();
633      SmallVector<uint64_t, 8> Words;
634      Words.resize(NumWords);
635      for (unsigned i = 0; i != NumWords; ++i)
636        Words[i] = DecodeSignRotatedValue(Record[i]);
637      V = ConstantInt::get(APInt(cast<IntegerType>(CurTy)->getBitWidth(),
638                                 NumWords, &Words[0]));
639      break;
640    }
641    case bitc::CST_CODE_FLOAT: {    // FLOAT: [fpval]
642      if (Record.empty())
643        return Error("Invalid FLOAT record");
644      if (CurTy == Type::FloatTy)
645        V = ConstantFP::get(CurTy, APFloat(APInt(32, (uint32_t)Record[0])));
646      else if (CurTy == Type::DoubleTy)
647        V = ConstantFP::get(CurTy, APFloat(APInt(64, Record[0])));
648      else if (CurTy == Type::X86_FP80Ty)
649        V = ConstantFP::get(CurTy, APFloat(APInt(80, 2, &Record[0])));
650      else if (CurTy == Type::FP128Ty)
651        V = ConstantFP::get(CurTy, APFloat(APInt(128, 2, &Record[0]), true));
652      else if (CurTy == Type::PPC_FP128Ty)
653        V = ConstantFP::get(CurTy, APFloat(APInt(128, 2, &Record[0])));
654      else
655        V = UndefValue::get(CurTy);
656      break;
657    }
658
659    case bitc::CST_CODE_AGGREGATE: {// AGGREGATE: [n x value number]
660      if (Record.empty())
661        return Error("Invalid CST_AGGREGATE record");
662
663      unsigned Size = Record.size();
664      std::vector<Constant*> Elts;
665
666      if (const StructType *STy = dyn_cast<StructType>(CurTy)) {
667        for (unsigned i = 0; i != Size; ++i)
668          Elts.push_back(ValueList.getConstantFwdRef(Record[i],
669                                                     STy->getElementType(i)));
670        V = ConstantStruct::get(STy, Elts);
671      } else if (const ArrayType *ATy = dyn_cast<ArrayType>(CurTy)) {
672        const Type *EltTy = ATy->getElementType();
673        for (unsigned i = 0; i != Size; ++i)
674          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
675        V = ConstantArray::get(ATy, Elts);
676      } else if (const VectorType *VTy = dyn_cast<VectorType>(CurTy)) {
677        const Type *EltTy = VTy->getElementType();
678        for (unsigned i = 0; i != Size; ++i)
679          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
680        V = ConstantVector::get(Elts);
681      } else {
682        V = UndefValue::get(CurTy);
683      }
684      break;
685    }
686    case bitc::CST_CODE_STRING: { // STRING: [values]
687      if (Record.empty())
688        return Error("Invalid CST_AGGREGATE record");
689
690      const ArrayType *ATy = cast<ArrayType>(CurTy);
691      const Type *EltTy = ATy->getElementType();
692
693      unsigned Size = Record.size();
694      std::vector<Constant*> Elts;
695      for (unsigned i = 0; i != Size; ++i)
696        Elts.push_back(ConstantInt::get(EltTy, Record[i]));
697      V = ConstantArray::get(ATy, Elts);
698      break;
699    }
700    case bitc::CST_CODE_CSTRING: { // CSTRING: [values]
701      if (Record.empty())
702        return Error("Invalid CST_AGGREGATE record");
703
704      const ArrayType *ATy = cast<ArrayType>(CurTy);
705      const Type *EltTy = ATy->getElementType();
706
707      unsigned Size = Record.size();
708      std::vector<Constant*> Elts;
709      for (unsigned i = 0; i != Size; ++i)
710        Elts.push_back(ConstantInt::get(EltTy, Record[i]));
711      Elts.push_back(Constant::getNullValue(EltTy));
712      V = ConstantArray::get(ATy, Elts);
713      break;
714    }
715    case bitc::CST_CODE_CE_BINOP: {  // CE_BINOP: [opcode, opval, opval]
716      if (Record.size() < 3) return Error("Invalid CE_BINOP record");
717      int Opc = GetDecodedBinaryOpcode(Record[0], CurTy);
718      if (Opc < 0) {
719        V = UndefValue::get(CurTy);  // Unknown binop.
720      } else {
721        Constant *LHS = ValueList.getConstantFwdRef(Record[1], CurTy);
722        Constant *RHS = ValueList.getConstantFwdRef(Record[2], CurTy);
723        V = ConstantExpr::get(Opc, LHS, RHS);
724      }
725      break;
726    }
727    case bitc::CST_CODE_CE_CAST: {  // CE_CAST: [opcode, opty, opval]
728      if (Record.size() < 3) return Error("Invalid CE_CAST record");
729      int Opc = GetDecodedCastOpcode(Record[0]);
730      if (Opc < 0) {
731        V = UndefValue::get(CurTy);  // Unknown cast.
732      } else {
733        const Type *OpTy = getTypeByID(Record[1]);
734        if (!OpTy) return Error("Invalid CE_CAST record");
735        Constant *Op = ValueList.getConstantFwdRef(Record[2], OpTy);
736        V = ConstantExpr::getCast(Opc, Op, CurTy);
737      }
738      break;
739    }
740    case bitc::CST_CODE_CE_GEP: {  // CE_GEP:        [n x operands]
741      if (Record.size() & 1) return Error("Invalid CE_GEP record");
742      SmallVector<Constant*, 16> Elts;
743      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
744        const Type *ElTy = getTypeByID(Record[i]);
745        if (!ElTy) return Error("Invalid CE_GEP record");
746        Elts.push_back(ValueList.getConstantFwdRef(Record[i+1], ElTy));
747      }
748      V = ConstantExpr::getGetElementPtr(Elts[0], &Elts[1], Elts.size()-1);
749      break;
750    }
751    case bitc::CST_CODE_CE_SELECT:  // CE_SELECT: [opval#, opval#, opval#]
752      if (Record.size() < 3) return Error("Invalid CE_SELECT record");
753      V = ConstantExpr::getSelect(ValueList.getConstantFwdRef(Record[0],
754                                                              Type::Int1Ty),
755                                  ValueList.getConstantFwdRef(Record[1],CurTy),
756                                  ValueList.getConstantFwdRef(Record[2],CurTy));
757      break;
758    case bitc::CST_CODE_CE_EXTRACTELT: { // CE_EXTRACTELT: [opty, opval, opval]
759      if (Record.size() < 3) return Error("Invalid CE_EXTRACTELT record");
760      const VectorType *OpTy =
761        dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
762      if (OpTy == 0) return Error("Invalid CE_EXTRACTELT record");
763      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
764      Constant *Op1 = ValueList.getConstantFwdRef(Record[2],
765                                                  OpTy->getElementType());
766      V = ConstantExpr::getExtractElement(Op0, Op1);
767      break;
768    }
769    case bitc::CST_CODE_CE_INSERTELT: { // CE_INSERTELT: [opval, opval, opval]
770      const VectorType *OpTy = dyn_cast<VectorType>(CurTy);
771      if (Record.size() < 3 || OpTy == 0)
772        return Error("Invalid CE_INSERTELT record");
773      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
774      Constant *Op1 = ValueList.getConstantFwdRef(Record[1],
775                                                  OpTy->getElementType());
776      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], Type::Int32Ty);
777      V = ConstantExpr::getInsertElement(Op0, Op1, Op2);
778      break;
779    }
780    case bitc::CST_CODE_CE_SHUFFLEVEC: { // CE_SHUFFLEVEC: [opval, opval, opval]
781      const VectorType *OpTy = dyn_cast<VectorType>(CurTy);
782      if (Record.size() < 3 || OpTy == 0)
783        return Error("Invalid CE_INSERTELT record");
784      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
785      Constant *Op1 = ValueList.getConstantFwdRef(Record[1], OpTy);
786      const Type *ShufTy=VectorType::get(Type::Int32Ty, OpTy->getNumElements());
787      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], ShufTy);
788      V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
789      break;
790    }
791    case bitc::CST_CODE_CE_CMP: {     // CE_CMP: [opty, opval, opval, pred]
792      if (Record.size() < 4) return Error("Invalid CE_CMP record");
793      const Type *OpTy = getTypeByID(Record[0]);
794      if (OpTy == 0) return Error("Invalid CE_CMP record");
795      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
796      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
797
798      if (OpTy->isFloatingPoint())
799        V = ConstantExpr::getFCmp(Record[3], Op0, Op1);
800      else
801        V = ConstantExpr::getICmp(Record[3], Op0, Op1);
802      break;
803    }
804    case bitc::CST_CODE_INLINEASM: {
805      if (Record.size() < 2) return Error("Invalid INLINEASM record");
806      std::string AsmStr, ConstrStr;
807      bool HasSideEffects = Record[0];
808      unsigned AsmStrSize = Record[1];
809      if (2+AsmStrSize >= Record.size())
810        return Error("Invalid INLINEASM record");
811      unsigned ConstStrSize = Record[2+AsmStrSize];
812      if (3+AsmStrSize+ConstStrSize > Record.size())
813        return Error("Invalid INLINEASM record");
814
815      for (unsigned i = 0; i != AsmStrSize; ++i)
816        AsmStr += (char)Record[2+i];
817      for (unsigned i = 0; i != ConstStrSize; ++i)
818        ConstrStr += (char)Record[3+AsmStrSize+i];
819      const PointerType *PTy = cast<PointerType>(CurTy);
820      V = InlineAsm::get(cast<FunctionType>(PTy->getElementType()),
821                         AsmStr, ConstrStr, HasSideEffects);
822      break;
823    }
824    }
825
826    ValueList.AssignValue(V, NextCstNo);
827    ++NextCstNo;
828  }
829}
830
831/// RememberAndSkipFunctionBody - When we see the block for a function body,
832/// remember where it is and then skip it.  This lets us lazily deserialize the
833/// functions.
834bool BitcodeReader::RememberAndSkipFunctionBody() {
835  // Get the function we are talking about.
836  if (FunctionsWithBodies.empty())
837    return Error("Insufficient function protos");
838
839  Function *Fn = FunctionsWithBodies.back();
840  FunctionsWithBodies.pop_back();
841
842  // Save the current stream state.
843  uint64_t CurBit = Stream.GetCurrentBitNo();
844  DeferredFunctionInfo[Fn] = std::make_pair(CurBit, Fn->getLinkage());
845
846  // Set the functions linkage to GhostLinkage so we know it is lazily
847  // deserialized.
848  Fn->setLinkage(GlobalValue::GhostLinkage);
849
850  // Skip over the function block for now.
851  if (Stream.SkipBlock())
852    return Error("Malformed block record");
853  return false;
854}
855
856bool BitcodeReader::ParseModule(const std::string &ModuleID) {
857  // Reject multiple MODULE_BLOCK's in a single bitstream.
858  if (TheModule)
859    return Error("Multiple MODULE_BLOCKs in same stream");
860
861  if (Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
862    return Error("Malformed block record");
863
864  // Otherwise, create the module.
865  TheModule = new Module(ModuleID);
866
867  SmallVector<uint64_t, 64> Record;
868  std::vector<std::string> SectionTable;
869  std::vector<std::string> CollectorTable;
870
871  // Read all the records for this module.
872  while (!Stream.AtEndOfStream()) {
873    unsigned Code = Stream.ReadCode();
874    if (Code == bitc::END_BLOCK) {
875      if (Stream.ReadBlockEnd())
876        return Error("Error at end of module block");
877
878      // Patch the initializers for globals and aliases up.
879      ResolveGlobalAndAliasInits();
880      if (!GlobalInits.empty() || !AliasInits.empty())
881        return Error("Malformed global initializer set");
882      if (!FunctionsWithBodies.empty())
883        return Error("Too few function bodies found");
884
885      // Look for intrinsic functions which need to be upgraded at some point
886      for (Module::iterator FI = TheModule->begin(), FE = TheModule->end();
887           FI != FE; ++FI) {
888        Function* NewFn;
889        if (UpgradeIntrinsicFunction(FI, NewFn))
890          UpgradedIntrinsics.push_back(std::make_pair(FI, NewFn));
891      }
892
893      // Force deallocation of memory for these vectors to favor the client that
894      // want lazy deserialization.
895      std::vector<std::pair<GlobalVariable*, unsigned> >().swap(GlobalInits);
896      std::vector<std::pair<GlobalAlias*, unsigned> >().swap(AliasInits);
897      std::vector<Function*>().swap(FunctionsWithBodies);
898      return false;
899    }
900
901    if (Code == bitc::ENTER_SUBBLOCK) {
902      switch (Stream.ReadSubBlockID()) {
903      default:  // Skip unknown content.
904        if (Stream.SkipBlock())
905          return Error("Malformed block record");
906        break;
907      case bitc::BLOCKINFO_BLOCK_ID:
908        if (Stream.ReadBlockInfoBlock())
909          return Error("Malformed BlockInfoBlock");
910        break;
911      case bitc::PARAMATTR_BLOCK_ID:
912        if (ParseParamAttrBlock())
913          return true;
914        break;
915      case bitc::TYPE_BLOCK_ID:
916        if (ParseTypeTable())
917          return true;
918        break;
919      case bitc::TYPE_SYMTAB_BLOCK_ID:
920        if (ParseTypeSymbolTable())
921          return true;
922        break;
923      case bitc::VALUE_SYMTAB_BLOCK_ID:
924        if (ParseValueSymbolTable())
925          return true;
926        break;
927      case bitc::CONSTANTS_BLOCK_ID:
928        if (ParseConstants() || ResolveGlobalAndAliasInits())
929          return true;
930        break;
931      case bitc::FUNCTION_BLOCK_ID:
932        // If this is the first function body we've seen, reverse the
933        // FunctionsWithBodies list.
934        if (!HasReversedFunctionsWithBodies) {
935          std::reverse(FunctionsWithBodies.begin(), FunctionsWithBodies.end());
936          HasReversedFunctionsWithBodies = true;
937        }
938
939        if (RememberAndSkipFunctionBody())
940          return true;
941        break;
942      }
943      continue;
944    }
945
946    if (Code == bitc::DEFINE_ABBREV) {
947      Stream.ReadAbbrevRecord();
948      continue;
949    }
950
951    // Read a record.
952    switch (Stream.ReadRecord(Code, Record)) {
953    default: break;  // Default behavior, ignore unknown content.
954    case bitc::MODULE_CODE_VERSION:  // VERSION: [version#]
955      if (Record.size() < 1)
956        return Error("Malformed MODULE_CODE_VERSION");
957      // Only version #0 is supported so far.
958      if (Record[0] != 0)
959        return Error("Unknown bitstream version!");
960      break;
961    case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
962      std::string S;
963      if (ConvertToString(Record, 0, S))
964        return Error("Invalid MODULE_CODE_TRIPLE record");
965      TheModule->setTargetTriple(S);
966      break;
967    }
968    case bitc::MODULE_CODE_DATALAYOUT: {  // DATALAYOUT: [strchr x N]
969      std::string S;
970      if (ConvertToString(Record, 0, S))
971        return Error("Invalid MODULE_CODE_DATALAYOUT record");
972      TheModule->setDataLayout(S);
973      break;
974    }
975    case bitc::MODULE_CODE_ASM: {  // ASM: [strchr x N]
976      std::string S;
977      if (ConvertToString(Record, 0, S))
978        return Error("Invalid MODULE_CODE_ASM record");
979      TheModule->setModuleInlineAsm(S);
980      break;
981    }
982    case bitc::MODULE_CODE_DEPLIB: {  // DEPLIB: [strchr x N]
983      std::string S;
984      if (ConvertToString(Record, 0, S))
985        return Error("Invalid MODULE_CODE_DEPLIB record");
986      TheModule->addLibrary(S);
987      break;
988    }
989    case bitc::MODULE_CODE_SECTIONNAME: {  // SECTIONNAME: [strchr x N]
990      std::string S;
991      if (ConvertToString(Record, 0, S))
992        return Error("Invalid MODULE_CODE_SECTIONNAME record");
993      SectionTable.push_back(S);
994      break;
995    }
996    case bitc::MODULE_CODE_COLLECTORNAME: {  // SECTIONNAME: [strchr x N]
997      std::string S;
998      if (ConvertToString(Record, 0, S))
999        return Error("Invalid MODULE_CODE_COLLECTORNAME record");
1000      CollectorTable.push_back(S);
1001      break;
1002    }
1003    // GLOBALVAR: [pointer type, isconst, initid,
1004    //             linkage, alignment, section, visibility, threadlocal]
1005    case bitc::MODULE_CODE_GLOBALVAR: {
1006      if (Record.size() < 6)
1007        return Error("Invalid MODULE_CODE_GLOBALVAR record");
1008      const Type *Ty = getTypeByID(Record[0]);
1009      if (!isa<PointerType>(Ty))
1010        return Error("Global not a pointer type!");
1011      unsigned AddressSpace = cast<PointerType>(Ty)->getAddressSpace();
1012      Ty = cast<PointerType>(Ty)->getElementType();
1013
1014      bool isConstant = Record[1];
1015      GlobalValue::LinkageTypes Linkage = GetDecodedLinkage(Record[3]);
1016      unsigned Alignment = (1 << Record[4]) >> 1;
1017      std::string Section;
1018      if (Record[5]) {
1019        if (Record[5]-1 >= SectionTable.size())
1020          return Error("Invalid section ID");
1021        Section = SectionTable[Record[5]-1];
1022      }
1023      GlobalValue::VisibilityTypes Visibility = GlobalValue::DefaultVisibility;
1024      if (Record.size() > 6)
1025        Visibility = GetDecodedVisibility(Record[6]);
1026      bool isThreadLocal = false;
1027      if (Record.size() > 7)
1028        isThreadLocal = Record[7];
1029
1030      GlobalVariable *NewGV =
1031        new GlobalVariable(Ty, isConstant, Linkage, 0, "", TheModule,
1032                           isThreadLocal, AddressSpace);
1033      NewGV->setAlignment(Alignment);
1034      if (!Section.empty())
1035        NewGV->setSection(Section);
1036      NewGV->setVisibility(Visibility);
1037      NewGV->setThreadLocal(isThreadLocal);
1038
1039      ValueList.push_back(NewGV);
1040
1041      // Remember which value to use for the global initializer.
1042      if (unsigned InitID = Record[2])
1043        GlobalInits.push_back(std::make_pair(NewGV, InitID-1));
1044      break;
1045    }
1046    // FUNCTION:  [type, callingconv, isproto, linkage, paramattr,
1047    //             alignment, section, visibility, collector]
1048    case bitc::MODULE_CODE_FUNCTION: {
1049      if (Record.size() < 8)
1050        return Error("Invalid MODULE_CODE_FUNCTION record");
1051      const Type *Ty = getTypeByID(Record[0]);
1052      if (!isa<PointerType>(Ty))
1053        return Error("Function not a pointer type!");
1054      const FunctionType *FTy =
1055        dyn_cast<FunctionType>(cast<PointerType>(Ty)->getElementType());
1056      if (!FTy)
1057        return Error("Function not a pointer to function type!");
1058
1059      Function *Func = new Function(FTy, GlobalValue::ExternalLinkage,
1060                                    "", TheModule);
1061
1062      Func->setCallingConv(Record[1]);
1063      bool isProto = Record[2];
1064      Func->setLinkage(GetDecodedLinkage(Record[3]));
1065      const ParamAttrsList *PAL = getParamAttrs(Record[4]);
1066      Func->setParamAttrs(PAL);
1067
1068      Func->setAlignment((1 << Record[5]) >> 1);
1069      if (Record[6]) {
1070        if (Record[6]-1 >= SectionTable.size())
1071          return Error("Invalid section ID");
1072        Func->setSection(SectionTable[Record[6]-1]);
1073      }
1074      Func->setVisibility(GetDecodedVisibility(Record[7]));
1075      if (Record.size() > 8 && Record[8]) {
1076        if (Record[8]-1 > CollectorTable.size())
1077          return Error("Invalid collector ID");
1078        Func->setCollector(CollectorTable[Record[8]-1].c_str());
1079      }
1080
1081      ValueList.push_back(Func);
1082
1083      // If this is a function with a body, remember the prototype we are
1084      // creating now, so that we can match up the body with them later.
1085      if (!isProto)
1086        FunctionsWithBodies.push_back(Func);
1087      break;
1088    }
1089    // ALIAS: [alias type, aliasee val#, linkage]
1090    // ALIAS: [alias type, aliasee val#, linkage, visibility]
1091    case bitc::MODULE_CODE_ALIAS: {
1092      if (Record.size() < 3)
1093        return Error("Invalid MODULE_ALIAS record");
1094      const Type *Ty = getTypeByID(Record[0]);
1095      if (!isa<PointerType>(Ty))
1096        return Error("Function not a pointer type!");
1097
1098      GlobalAlias *NewGA = new GlobalAlias(Ty, GetDecodedLinkage(Record[2]),
1099                                           "", 0, TheModule);
1100      // Old bitcode files didn't have visibility field.
1101      if (Record.size() > 3)
1102        NewGA->setVisibility(GetDecodedVisibility(Record[3]));
1103      ValueList.push_back(NewGA);
1104      AliasInits.push_back(std::make_pair(NewGA, Record[1]));
1105      break;
1106    }
1107    /// MODULE_CODE_PURGEVALS: [numvals]
1108    case bitc::MODULE_CODE_PURGEVALS:
1109      // Trim down the value list to the specified size.
1110      if (Record.size() < 1 || Record[0] > ValueList.size())
1111        return Error("Invalid MODULE_PURGEVALS record");
1112      ValueList.shrinkTo(Record[0]);
1113      break;
1114    }
1115    Record.clear();
1116  }
1117
1118  return Error("Premature end of bitstream");
1119}
1120
1121
1122bool BitcodeReader::ParseBitcode() {
1123  TheModule = 0;
1124
1125  if (Buffer->getBufferSize() & 3)
1126    return Error("Bitcode stream should be a multiple of 4 bytes in length");
1127
1128  unsigned char *BufPtr = (unsigned char *)Buffer->getBufferStart();
1129  Stream.init(BufPtr, BufPtr+Buffer->getBufferSize());
1130
1131  // Sniff for the signature.
1132  if (Stream.Read(8) != 'B' ||
1133      Stream.Read(8) != 'C' ||
1134      Stream.Read(4) != 0x0 ||
1135      Stream.Read(4) != 0xC ||
1136      Stream.Read(4) != 0xE ||
1137      Stream.Read(4) != 0xD)
1138    return Error("Invalid bitcode signature");
1139
1140  // We expect a number of well-defined blocks, though we don't necessarily
1141  // need to understand them all.
1142  while (!Stream.AtEndOfStream()) {
1143    unsigned Code = Stream.ReadCode();
1144
1145    if (Code != bitc::ENTER_SUBBLOCK)
1146      return Error("Invalid record at top-level");
1147
1148    unsigned BlockID = Stream.ReadSubBlockID();
1149
1150    // We only know the MODULE subblock ID.
1151    switch (BlockID) {
1152    case bitc::BLOCKINFO_BLOCK_ID:
1153      if (Stream.ReadBlockInfoBlock())
1154        return Error("Malformed BlockInfoBlock");
1155      break;
1156    case bitc::MODULE_BLOCK_ID:
1157      if (ParseModule(Buffer->getBufferIdentifier()))
1158        return true;
1159      break;
1160    default:
1161      if (Stream.SkipBlock())
1162        return Error("Malformed block record");
1163      break;
1164    }
1165  }
1166
1167  return false;
1168}
1169
1170
1171/// ParseFunctionBody - Lazily parse the specified function body block.
1172bool BitcodeReader::ParseFunctionBody(Function *F) {
1173  if (Stream.EnterSubBlock(bitc::FUNCTION_BLOCK_ID))
1174    return Error("Malformed block record");
1175
1176  unsigned ModuleValueListSize = ValueList.size();
1177
1178  // Add all the function arguments to the value table.
1179  for(Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
1180    ValueList.push_back(I);
1181
1182  unsigned NextValueNo = ValueList.size();
1183  BasicBlock *CurBB = 0;
1184  unsigned CurBBNo = 0;
1185
1186  // Read all the records.
1187  SmallVector<uint64_t, 64> Record;
1188  while (1) {
1189    unsigned Code = Stream.ReadCode();
1190    if (Code == bitc::END_BLOCK) {
1191      if (Stream.ReadBlockEnd())
1192        return Error("Error at end of function block");
1193      break;
1194    }
1195
1196    if (Code == bitc::ENTER_SUBBLOCK) {
1197      switch (Stream.ReadSubBlockID()) {
1198      default:  // Skip unknown content.
1199        if (Stream.SkipBlock())
1200          return Error("Malformed block record");
1201        break;
1202      case bitc::CONSTANTS_BLOCK_ID:
1203        if (ParseConstants()) return true;
1204        NextValueNo = ValueList.size();
1205        break;
1206      case bitc::VALUE_SYMTAB_BLOCK_ID:
1207        if (ParseValueSymbolTable()) return true;
1208        break;
1209      }
1210      continue;
1211    }
1212
1213    if (Code == bitc::DEFINE_ABBREV) {
1214      Stream.ReadAbbrevRecord();
1215      continue;
1216    }
1217
1218    // Read a record.
1219    Record.clear();
1220    Instruction *I = 0;
1221    switch (Stream.ReadRecord(Code, Record)) {
1222    default: // Default behavior: reject
1223      return Error("Unknown instruction");
1224    case bitc::FUNC_CODE_DECLAREBLOCKS:     // DECLAREBLOCKS: [nblocks]
1225      if (Record.size() < 1 || Record[0] == 0)
1226        return Error("Invalid DECLAREBLOCKS record");
1227      // Create all the basic blocks for the function.
1228      FunctionBBs.resize(Record[0]);
1229      for (unsigned i = 0, e = FunctionBBs.size(); i != e; ++i)
1230        FunctionBBs[i] = new BasicBlock("", F);
1231      CurBB = FunctionBBs[0];
1232      continue;
1233
1234    case bitc::FUNC_CODE_INST_BB_UNWINDDEST:   // BB_UNWINDDEST: [bb#]
1235      if (CurBB->getUnwindDest())
1236        return Error("Only permit one BB_UNWINDDEST per BB");
1237      if (Record.size() != 1)
1238        return Error("Invalid BB_UNWINDDEST record");
1239
1240      CurBB->setUnwindDest(getBasicBlock(Record[0]));
1241      continue;
1242
1243    case bitc::FUNC_CODE_INST_BINOP: {    // BINOP: [opval, ty, opval, opcode]
1244      unsigned OpNum = 0;
1245      Value *LHS, *RHS;
1246      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
1247          getValue(Record, OpNum, LHS->getType(), RHS) ||
1248          OpNum+1 != Record.size())
1249        return Error("Invalid BINOP record");
1250
1251      int Opc = GetDecodedBinaryOpcode(Record[OpNum], LHS->getType());
1252      if (Opc == -1) return Error("Invalid BINOP record");
1253      I = BinaryOperator::create((Instruction::BinaryOps)Opc, LHS, RHS);
1254      break;
1255    }
1256    case bitc::FUNC_CODE_INST_CAST: {    // CAST: [opval, opty, destty, castopc]
1257      unsigned OpNum = 0;
1258      Value *Op;
1259      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
1260          OpNum+2 != Record.size())
1261        return Error("Invalid CAST record");
1262
1263      const Type *ResTy = getTypeByID(Record[OpNum]);
1264      int Opc = GetDecodedCastOpcode(Record[OpNum+1]);
1265      if (Opc == -1 || ResTy == 0)
1266        return Error("Invalid CAST record");
1267      I = CastInst::create((Instruction::CastOps)Opc, Op, ResTy);
1268      break;
1269    }
1270    case bitc::FUNC_CODE_INST_GEP: { // GEP: [n x operands]
1271      unsigned OpNum = 0;
1272      Value *BasePtr;
1273      if (getValueTypePair(Record, OpNum, NextValueNo, BasePtr))
1274        return Error("Invalid GEP record");
1275
1276      SmallVector<Value*, 16> GEPIdx;
1277      while (OpNum != Record.size()) {
1278        Value *Op;
1279        if (getValueTypePair(Record, OpNum, NextValueNo, Op))
1280          return Error("Invalid GEP record");
1281        GEPIdx.push_back(Op);
1282      }
1283
1284      I = new GetElementPtrInst(BasePtr, GEPIdx.begin(), GEPIdx.end());
1285      break;
1286    }
1287
1288    case bitc::FUNC_CODE_INST_SELECT: { // SELECT: [opval, ty, opval, opval]
1289      unsigned OpNum = 0;
1290      Value *TrueVal, *FalseVal, *Cond;
1291      if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
1292          getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
1293          getValue(Record, OpNum, Type::Int1Ty, Cond))
1294        return Error("Invalid SELECT record");
1295
1296      I = new SelectInst(Cond, TrueVal, FalseVal);
1297      break;
1298    }
1299
1300    case bitc::FUNC_CODE_INST_EXTRACTELT: { // EXTRACTELT: [opty, opval, opval]
1301      unsigned OpNum = 0;
1302      Value *Vec, *Idx;
1303      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
1304          getValue(Record, OpNum, Type::Int32Ty, Idx))
1305        return Error("Invalid EXTRACTELT record");
1306      I = new ExtractElementInst(Vec, Idx);
1307      break;
1308    }
1309
1310    case bitc::FUNC_CODE_INST_INSERTELT: { // INSERTELT: [ty, opval,opval,opval]
1311      unsigned OpNum = 0;
1312      Value *Vec, *Elt, *Idx;
1313      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
1314          getValue(Record, OpNum,
1315                   cast<VectorType>(Vec->getType())->getElementType(), Elt) ||
1316          getValue(Record, OpNum, Type::Int32Ty, Idx))
1317        return Error("Invalid INSERTELT record");
1318      I = new InsertElementInst(Vec, Elt, Idx);
1319      break;
1320    }
1321
1322    case bitc::FUNC_CODE_INST_SHUFFLEVEC: {// SHUFFLEVEC: [opval,ty,opval,opval]
1323      unsigned OpNum = 0;
1324      Value *Vec1, *Vec2, *Mask;
1325      if (getValueTypePair(Record, OpNum, NextValueNo, Vec1) ||
1326          getValue(Record, OpNum, Vec1->getType(), Vec2))
1327        return Error("Invalid SHUFFLEVEC record");
1328
1329      const Type *MaskTy =
1330        VectorType::get(Type::Int32Ty,
1331                        cast<VectorType>(Vec1->getType())->getNumElements());
1332
1333      if (getValue(Record, OpNum, MaskTy, Mask))
1334        return Error("Invalid SHUFFLEVEC record");
1335      I = new ShuffleVectorInst(Vec1, Vec2, Mask);
1336      break;
1337    }
1338
1339    case bitc::FUNC_CODE_INST_CMP: { // CMP: [opty, opval, opval, pred]
1340      unsigned OpNum = 0;
1341      Value *LHS, *RHS;
1342      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
1343          getValue(Record, OpNum, LHS->getType(), RHS) ||
1344          OpNum+1 != Record.size())
1345        return Error("Invalid CMP record");
1346
1347      if (LHS->getType()->isFPOrFPVector())
1348        I = new FCmpInst((FCmpInst::Predicate)Record[OpNum], LHS, RHS);
1349      else
1350        I = new ICmpInst((ICmpInst::Predicate)Record[OpNum], LHS, RHS);
1351      break;
1352    }
1353    case bitc::FUNC_CODE_INST_GETRESULT: { // GETRESULT: [ty, val, n]
1354      if (Record.size() != 2)
1355        return Error("Invalid GETRESULT record");
1356      unsigned OpNum = 0;
1357      Value *Op;
1358      getValueTypePair(Record, OpNum, NextValueNo, Op);
1359      unsigned Index = Record[1];
1360      I = new GetResultInst(Op, Index);
1361      break;
1362    }
1363
1364    case bitc::FUNC_CODE_INST_RET: // RET: [opty,opval<optional>]
1365      {
1366        unsigned Size = Record.size();
1367        if (Size == 0) {
1368          I = new ReturnInst();
1369          break;
1370        } else {
1371          unsigned OpNum = 0;
1372          SmallVector<Value *,4> Vs;
1373          do {
1374            Value *Op = NULL;
1375            if (getValueTypePair(Record, OpNum, NextValueNo, Op))
1376              return Error("Invalid RET record");
1377            Vs.push_back(Op);
1378          } while(OpNum != Record.size());
1379
1380          // SmallVector Vs has at least one element.
1381          I = new ReturnInst(&Vs[0], Vs.size());
1382          break;
1383        }
1384      }
1385    case bitc::FUNC_CODE_INST_BR: { // BR: [bb#, bb#, opval] or [bb#]
1386      if (Record.size() != 1 && Record.size() != 3)
1387        return Error("Invalid BR record");
1388      BasicBlock *TrueDest = getBasicBlock(Record[0]);
1389      if (TrueDest == 0)
1390        return Error("Invalid BR record");
1391
1392      if (Record.size() == 1)
1393        I = new BranchInst(TrueDest);
1394      else {
1395        BasicBlock *FalseDest = getBasicBlock(Record[1]);
1396        Value *Cond = getFnValueByID(Record[2], Type::Int1Ty);
1397        if (FalseDest == 0 || Cond == 0)
1398          return Error("Invalid BR record");
1399        I = new BranchInst(TrueDest, FalseDest, Cond);
1400      }
1401      break;
1402    }
1403    case bitc::FUNC_CODE_INST_SWITCH: { // SWITCH: [opty, opval, n, n x ops]
1404      if (Record.size() < 3 || (Record.size() & 1) == 0)
1405        return Error("Invalid SWITCH record");
1406      const Type *OpTy = getTypeByID(Record[0]);
1407      Value *Cond = getFnValueByID(Record[1], OpTy);
1408      BasicBlock *Default = getBasicBlock(Record[2]);
1409      if (OpTy == 0 || Cond == 0 || Default == 0)
1410        return Error("Invalid SWITCH record");
1411      unsigned NumCases = (Record.size()-3)/2;
1412      SwitchInst *SI = new SwitchInst(Cond, Default, NumCases);
1413      for (unsigned i = 0, e = NumCases; i != e; ++i) {
1414        ConstantInt *CaseVal =
1415          dyn_cast_or_null<ConstantInt>(getFnValueByID(Record[3+i*2], OpTy));
1416        BasicBlock *DestBB = getBasicBlock(Record[1+3+i*2]);
1417        if (CaseVal == 0 || DestBB == 0) {
1418          delete SI;
1419          return Error("Invalid SWITCH record!");
1420        }
1421        SI->addCase(CaseVal, DestBB);
1422      }
1423      I = SI;
1424      break;
1425    }
1426
1427    case bitc::FUNC_CODE_INST_INVOKE: {
1428      // INVOKE: [attrs, cc, normBB, unwindBB, fnty, op0,op1,op2, ...]
1429      if (Record.size() < 4) return Error("Invalid INVOKE record");
1430      const ParamAttrsList *PAL = getParamAttrs(Record[0]);
1431      unsigned CCInfo = Record[1];
1432      BasicBlock *NormalBB = getBasicBlock(Record[2]);
1433      BasicBlock *UnwindBB = getBasicBlock(Record[3]);
1434
1435      unsigned OpNum = 4;
1436      Value *Callee;
1437      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
1438        return Error("Invalid INVOKE record");
1439
1440      const PointerType *CalleeTy = dyn_cast<PointerType>(Callee->getType());
1441      const FunctionType *FTy = !CalleeTy ? 0 :
1442        dyn_cast<FunctionType>(CalleeTy->getElementType());
1443
1444      // Check that the right number of fixed parameters are here.
1445      if (FTy == 0 || NormalBB == 0 || UnwindBB == 0 ||
1446          Record.size() < OpNum+FTy->getNumParams())
1447        return Error("Invalid INVOKE record");
1448
1449      SmallVector<Value*, 16> Ops;
1450      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
1451        Ops.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
1452        if (Ops.back() == 0) return Error("Invalid INVOKE record");
1453      }
1454
1455      if (!FTy->isVarArg()) {
1456        if (Record.size() != OpNum)
1457          return Error("Invalid INVOKE record");
1458      } else {
1459        // Read type/value pairs for varargs params.
1460        while (OpNum != Record.size()) {
1461          Value *Op;
1462          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
1463            return Error("Invalid INVOKE record");
1464          Ops.push_back(Op);
1465        }
1466      }
1467
1468      I = new InvokeInst(Callee, NormalBB, UnwindBB, Ops.begin(), Ops.end());
1469      cast<InvokeInst>(I)->setCallingConv(CCInfo);
1470      cast<InvokeInst>(I)->setParamAttrs(PAL);
1471      break;
1472    }
1473    case bitc::FUNC_CODE_INST_UNWIND: // UNWIND
1474      I = new UnwindInst();
1475      break;
1476    case bitc::FUNC_CODE_INST_UNREACHABLE: // UNREACHABLE
1477      I = new UnreachableInst();
1478      break;
1479    case bitc::FUNC_CODE_INST_PHI: { // PHI: [ty, val0,bb0, ...]
1480      if (Record.size() < 1 || ((Record.size()-1)&1))
1481        return Error("Invalid PHI record");
1482      const Type *Ty = getTypeByID(Record[0]);
1483      if (!Ty) return Error("Invalid PHI record");
1484
1485      PHINode *PN = new PHINode(Ty);
1486      PN->reserveOperandSpace(Record.size()-1);
1487
1488      for (unsigned i = 0, e = Record.size()-1; i != e; i += 2) {
1489        Value *V = getFnValueByID(Record[1+i], Ty);
1490        BasicBlock *BB = getBasicBlock(Record[2+i]);
1491        if (!V || !BB) return Error("Invalid PHI record");
1492        PN->addIncoming(V, BB);
1493      }
1494      I = PN;
1495      break;
1496    }
1497
1498    case bitc::FUNC_CODE_INST_MALLOC: { // MALLOC: [instty, op, align]
1499      if (Record.size() < 3)
1500        return Error("Invalid MALLOC record");
1501      const PointerType *Ty =
1502        dyn_cast_or_null<PointerType>(getTypeByID(Record[0]));
1503      Value *Size = getFnValueByID(Record[1], Type::Int32Ty);
1504      unsigned Align = Record[2];
1505      if (!Ty || !Size) return Error("Invalid MALLOC record");
1506      I = new MallocInst(Ty->getElementType(), Size, (1 << Align) >> 1);
1507      break;
1508    }
1509    case bitc::FUNC_CODE_INST_FREE: { // FREE: [op, opty]
1510      unsigned OpNum = 0;
1511      Value *Op;
1512      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
1513          OpNum != Record.size())
1514        return Error("Invalid FREE record");
1515      I = new FreeInst(Op);
1516      break;
1517    }
1518    case bitc::FUNC_CODE_INST_ALLOCA: { // ALLOCA: [instty, op, align]
1519      if (Record.size() < 3)
1520        return Error("Invalid ALLOCA record");
1521      const PointerType *Ty =
1522        dyn_cast_or_null<PointerType>(getTypeByID(Record[0]));
1523      Value *Size = getFnValueByID(Record[1], Type::Int32Ty);
1524      unsigned Align = Record[2];
1525      if (!Ty || !Size) return Error("Invalid ALLOCA record");
1526      I = new AllocaInst(Ty->getElementType(), Size, (1 << Align) >> 1);
1527      break;
1528    }
1529    case bitc::FUNC_CODE_INST_LOAD: { // LOAD: [opty, op, align, vol]
1530      unsigned OpNum = 0;
1531      Value *Op;
1532      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
1533          OpNum+2 != Record.size())
1534        return Error("Invalid LOAD record");
1535
1536      I = new LoadInst(Op, "", Record[OpNum+1], (1 << Record[OpNum]) >> 1);
1537      break;
1538    }
1539    case bitc::FUNC_CODE_INST_STORE2: { // STORE2:[ptrty, ptr, val, align, vol]
1540      unsigned OpNum = 0;
1541      Value *Val, *Ptr;
1542      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
1543          getValue(Record, OpNum,
1544                    cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
1545          OpNum+2 != Record.size())
1546        return Error("Invalid STORE record");
1547
1548      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1);
1549      break;
1550    }
1551    case bitc::FUNC_CODE_INST_STORE: { // STORE:[val, valty, ptr, align, vol]
1552      // FIXME: Legacy form of store instruction. Should be removed in LLVM 3.0.
1553      unsigned OpNum = 0;
1554      Value *Val, *Ptr;
1555      if (getValueTypePair(Record, OpNum, NextValueNo, Val) ||
1556          getValue(Record, OpNum, PointerType::getUnqual(Val->getType()), Ptr)||
1557          OpNum+2 != Record.size())
1558        return Error("Invalid STORE record");
1559
1560      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1);
1561      break;
1562    }
1563    case bitc::FUNC_CODE_INST_CALL: {
1564      // CALL: [paramattrs, cc, fnty, fnid, arg0, arg1...]
1565      if (Record.size() < 3)
1566        return Error("Invalid CALL record");
1567
1568      const ParamAttrsList *PAL = getParamAttrs(Record[0]);
1569      unsigned CCInfo = Record[1];
1570
1571      unsigned OpNum = 2;
1572      Value *Callee;
1573      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
1574        return Error("Invalid CALL record");
1575
1576      const PointerType *OpTy = dyn_cast<PointerType>(Callee->getType());
1577      const FunctionType *FTy = 0;
1578      if (OpTy) FTy = dyn_cast<FunctionType>(OpTy->getElementType());
1579      if (!FTy || Record.size() < FTy->getNumParams()+OpNum)
1580        return Error("Invalid CALL record");
1581
1582      SmallVector<Value*, 16> Args;
1583      // Read the fixed params.
1584      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
1585        if (FTy->getParamType(i)->getTypeID()==Type::LabelTyID)
1586          Args.push_back(getBasicBlock(Record[OpNum]));
1587        else
1588          Args.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
1589        if (Args.back() == 0) return Error("Invalid CALL record");
1590      }
1591
1592      // Read type/value pairs for varargs params.
1593      if (!FTy->isVarArg()) {
1594        if (OpNum != Record.size())
1595          return Error("Invalid CALL record");
1596      } else {
1597        while (OpNum != Record.size()) {
1598          Value *Op;
1599          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
1600            return Error("Invalid CALL record");
1601          Args.push_back(Op);
1602        }
1603      }
1604
1605      I = new CallInst(Callee, Args.begin(), Args.end());
1606      cast<CallInst>(I)->setCallingConv(CCInfo>>1);
1607      cast<CallInst>(I)->setTailCall(CCInfo & 1);
1608      cast<CallInst>(I)->setParamAttrs(PAL);
1609      break;
1610    }
1611    case bitc::FUNC_CODE_INST_VAARG: { // VAARG: [valistty, valist, instty]
1612      if (Record.size() < 3)
1613        return Error("Invalid VAARG record");
1614      const Type *OpTy = getTypeByID(Record[0]);
1615      Value *Op = getFnValueByID(Record[1], OpTy);
1616      const Type *ResTy = getTypeByID(Record[2]);
1617      if (!OpTy || !Op || !ResTy)
1618        return Error("Invalid VAARG record");
1619      I = new VAArgInst(Op, ResTy);
1620      break;
1621    }
1622    }
1623
1624    // Add instruction to end of current BB.  If there is no current BB, reject
1625    // this file.
1626    if (CurBB == 0) {
1627      delete I;
1628      return Error("Invalid instruction with no BB");
1629    }
1630    CurBB->getInstList().push_back(I);
1631
1632    // If this was a terminator instruction, move to the next block.
1633    if (isa<TerminatorInst>(I)) {
1634      ++CurBBNo;
1635      CurBB = CurBBNo < FunctionBBs.size() ? FunctionBBs[CurBBNo] : 0;
1636    }
1637
1638    // Non-void values get registered in the value table for future use.
1639    if (I && I->getType() != Type::VoidTy)
1640      ValueList.AssignValue(I, NextValueNo++);
1641  }
1642
1643  // Check the function list for unresolved values.
1644  if (Argument *A = dyn_cast<Argument>(ValueList.back())) {
1645    if (A->getParent() == 0) {
1646      // We found at least one unresolved value.  Nuke them all to avoid leaks.
1647      for (unsigned i = ModuleValueListSize, e = ValueList.size(); i != e; ++i){
1648        if ((A = dyn_cast<Argument>(ValueList.back())) && A->getParent() == 0) {
1649          A->replaceAllUsesWith(UndefValue::get(A->getType()));
1650          delete A;
1651        }
1652      }
1653      return Error("Never resolved value found in function!");
1654    }
1655  }
1656
1657  // Trim the value list down to the size it was before we parsed this function.
1658  ValueList.shrinkTo(ModuleValueListSize);
1659  std::vector<BasicBlock*>().swap(FunctionBBs);
1660
1661  return false;
1662}
1663
1664//===----------------------------------------------------------------------===//
1665// ModuleProvider implementation
1666//===----------------------------------------------------------------------===//
1667
1668
1669bool BitcodeReader::materializeFunction(Function *F, std::string *ErrInfo) {
1670  // If it already is material, ignore the request.
1671  if (!F->hasNotBeenReadFromBitcode()) return false;
1672
1673  DenseMap<Function*, std::pair<uint64_t, unsigned> >::iterator DFII =
1674    DeferredFunctionInfo.find(F);
1675  assert(DFII != DeferredFunctionInfo.end() && "Deferred function not found!");
1676
1677  // Move the bit stream to the saved position of the deferred function body and
1678  // restore the real linkage type for the function.
1679  Stream.JumpToBit(DFII->second.first);
1680  F->setLinkage((GlobalValue::LinkageTypes)DFII->second.second);
1681
1682  if (ParseFunctionBody(F)) {
1683    if (ErrInfo) *ErrInfo = ErrorString;
1684    return true;
1685  }
1686
1687  // Upgrade any old intrinsic calls in the function.
1688  for (UpgradedIntrinsicMap::iterator I = UpgradedIntrinsics.begin(),
1689       E = UpgradedIntrinsics.end(); I != E; ++I) {
1690    if (I->first != I->second) {
1691      for (Value::use_iterator UI = I->first->use_begin(),
1692           UE = I->first->use_end(); UI != UE; ) {
1693        if (CallInst* CI = dyn_cast<CallInst>(*UI++))
1694          UpgradeIntrinsicCall(CI, I->second);
1695      }
1696    }
1697  }
1698
1699  return false;
1700}
1701
1702void BitcodeReader::dematerializeFunction(Function *F) {
1703  // If this function isn't materialized, or if it is a proto, this is a noop.
1704  if (F->hasNotBeenReadFromBitcode() || F->isDeclaration())
1705    return;
1706
1707  assert(DeferredFunctionInfo.count(F) && "No info to read function later?");
1708
1709  // Just forget the function body, we can remat it later.
1710  F->deleteBody();
1711  F->setLinkage(GlobalValue::GhostLinkage);
1712}
1713
1714
1715Module *BitcodeReader::materializeModule(std::string *ErrInfo) {
1716  for (DenseMap<Function*, std::pair<uint64_t, unsigned> >::iterator I =
1717       DeferredFunctionInfo.begin(), E = DeferredFunctionInfo.end(); I != E;
1718       ++I) {
1719    Function *F = I->first;
1720    if (F->hasNotBeenReadFromBitcode() &&
1721        materializeFunction(F, ErrInfo))
1722      return 0;
1723  }
1724
1725  // Upgrade any intrinsic calls that slipped through (should not happen!) and
1726  // delete the old functions to clean up. We can't do this unless the entire
1727  // module is materialized because there could always be another function body
1728  // with calls to the old function.
1729  for (std::vector<std::pair<Function*, Function*> >::iterator I =
1730       UpgradedIntrinsics.begin(), E = UpgradedIntrinsics.end(); I != E; ++I) {
1731    if (I->first != I->second) {
1732      for (Value::use_iterator UI = I->first->use_begin(),
1733           UE = I->first->use_end(); UI != UE; ) {
1734        if (CallInst* CI = dyn_cast<CallInst>(*UI++))
1735          UpgradeIntrinsicCall(CI, I->second);
1736      }
1737      ValueList.replaceUsesOfWith(I->first, I->second);
1738      I->first->eraseFromParent();
1739    }
1740  }
1741  std::vector<std::pair<Function*, Function*> >().swap(UpgradedIntrinsics);
1742
1743  return TheModule;
1744}
1745
1746
1747/// This method is provided by the parent ModuleProvde class and overriden
1748/// here. It simply releases the module from its provided and frees up our
1749/// state.
1750/// @brief Release our hold on the generated module
1751Module *BitcodeReader::releaseModule(std::string *ErrInfo) {
1752  // Since we're losing control of this Module, we must hand it back complete
1753  Module *M = ModuleProvider::releaseModule(ErrInfo);
1754  FreeState();
1755  return M;
1756}
1757
1758
1759//===----------------------------------------------------------------------===//
1760// External interface
1761//===----------------------------------------------------------------------===//
1762
1763/// getBitcodeModuleProvider - lazy function-at-a-time loading from a file.
1764///
1765ModuleProvider *llvm::getBitcodeModuleProvider(MemoryBuffer *Buffer,
1766                                               std::string *ErrMsg) {
1767  BitcodeReader *R = new BitcodeReader(Buffer);
1768  if (R->ParseBitcode()) {
1769    if (ErrMsg)
1770      *ErrMsg = R->getErrorString();
1771
1772    // Don't let the BitcodeReader dtor delete 'Buffer'.
1773    R->releaseMemoryBuffer();
1774    delete R;
1775    return 0;
1776  }
1777  return R;
1778}
1779
1780/// ParseBitcodeFile - Read the specified bitcode file, returning the module.
1781/// If an error occurs, return null and fill in *ErrMsg if non-null.
1782Module *llvm::ParseBitcodeFile(MemoryBuffer *Buffer, std::string *ErrMsg){
1783  BitcodeReader *R;
1784  R = static_cast<BitcodeReader*>(getBitcodeModuleProvider(Buffer, ErrMsg));
1785  if (!R) return 0;
1786
1787  // Read in the entire module.
1788  Module *M = R->materializeModule(ErrMsg);
1789
1790  // Don't let the BitcodeReader dtor delete 'Buffer', regardless of whether
1791  // there was an error.
1792  R->releaseMemoryBuffer();
1793
1794  // If there was no error, tell ModuleProvider not to delete it when its dtor
1795  // is run.
1796  if (M)
1797    M = R->releaseModule(ErrMsg);
1798
1799  delete R;
1800  return M;
1801}
1802