BitcodeReader.cpp revision 8ba2d5befc05ca73d3bac8708819bbbe759e2cf9 
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/IntrinsicInst.h"
20#include "llvm/LLVMContext.h"
21#include "llvm/Metadata.h"
22#include "llvm/Module.h"
23#include "llvm/Operator.h"
24#include "llvm/AutoUpgrade.h"
25#include "llvm/ADT/SmallString.h"
26#include "llvm/ADT/SmallVector.h"
27#include "llvm/Support/MathExtras.h"
28#include "llvm/Support/MemoryBuffer.h"
29#include "llvm/OperandTraits.h"
30using namespace llvm;
31
32void BitcodeReader::FreeState() {
33  delete Buffer;
34  Buffer = 0;
35  std::vector<PATypeHolder>().swap(TypeList);
36  ValueList.clear();
37  MDValueList.clear();
38
39  std::vector<AttrListPtr>().swap(MAttributes);
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::WeakAnyLinkage;
67  case 2:  return GlobalValue::AppendingLinkage;
68  case 3:  return GlobalValue::InternalLinkage;
69  case 4:  return GlobalValue::LinkOnceAnyLinkage;
70  case 5:  return GlobalValue::DLLImportLinkage;
71  case 6:  return GlobalValue::DLLExportLinkage;
72  case 7:  return GlobalValue::ExternalWeakLinkage;
73  case 8:  return GlobalValue::CommonLinkage;
74  case 9:  return GlobalValue::PrivateLinkage;
75  case 10: return GlobalValue::WeakODRLinkage;
76  case 11: return GlobalValue::LinkOnceODRLinkage;
77  case 12: return GlobalValue::AvailableExternallyLinkage;
78  case 13: return GlobalValue::LinkerPrivateLinkage;
79  }
80}
81
82static GlobalValue::VisibilityTypes GetDecodedVisibility(unsigned Val) {
83  switch (Val) {
84  default: // Map unknown visibilities to default.
85  case 0: return GlobalValue::DefaultVisibility;
86  case 1: return GlobalValue::HiddenVisibility;
87  case 2: return GlobalValue::ProtectedVisibility;
88  }
89}
90
91static int GetDecodedCastOpcode(unsigned Val) {
92  switch (Val) {
93  default: return -1;
94  case bitc::CAST_TRUNC   : return Instruction::Trunc;
95  case bitc::CAST_ZEXT    : return Instruction::ZExt;
96  case bitc::CAST_SEXT    : return Instruction::SExt;
97  case bitc::CAST_FPTOUI  : return Instruction::FPToUI;
98  case bitc::CAST_FPTOSI  : return Instruction::FPToSI;
99  case bitc::CAST_UITOFP  : return Instruction::UIToFP;
100  case bitc::CAST_SITOFP  : return Instruction::SIToFP;
101  case bitc::CAST_FPTRUNC : return Instruction::FPTrunc;
102  case bitc::CAST_FPEXT   : return Instruction::FPExt;
103  case bitc::CAST_PTRTOINT: return Instruction::PtrToInt;
104  case bitc::CAST_INTTOPTR: return Instruction::IntToPtr;
105  case bitc::CAST_BITCAST : return Instruction::BitCast;
106  }
107}
108static int GetDecodedBinaryOpcode(unsigned Val, const Type *Ty) {
109  switch (Val) {
110  default: return -1;
111  case bitc::BINOP_ADD:
112    return Ty->isFPOrFPVector() ? Instruction::FAdd : Instruction::Add;
113  case bitc::BINOP_SUB:
114    return Ty->isFPOrFPVector() ? Instruction::FSub : Instruction::Sub;
115  case bitc::BINOP_MUL:
116    return Ty->isFPOrFPVector() ? Instruction::FMul : Instruction::Mul;
117  case bitc::BINOP_UDIV: return Instruction::UDiv;
118  case bitc::BINOP_SDIV:
119    return Ty->isFPOrFPVector() ? Instruction::FDiv : Instruction::SDiv;
120  case bitc::BINOP_UREM: return Instruction::URem;
121  case bitc::BINOP_SREM:
122    return Ty->isFPOrFPVector() ? Instruction::FRem : Instruction::SRem;
123  case bitc::BINOP_SHL:  return Instruction::Shl;
124  case bitc::BINOP_LSHR: return Instruction::LShr;
125  case bitc::BINOP_ASHR: return Instruction::AShr;
126  case bitc::BINOP_AND:  return Instruction::And;
127  case bitc::BINOP_OR:   return Instruction::Or;
128  case bitc::BINOP_XOR:  return Instruction::Xor;
129  }
130}
131
132namespace llvm {
133namespace {
134  /// @brief A class for maintaining the slot number definition
135  /// as a placeholder for the actual definition for forward constants defs.
136  class ConstantPlaceHolder : public ConstantExpr {
137    ConstantPlaceHolder();                       // DO NOT IMPLEMENT
138    void operator=(const ConstantPlaceHolder &); // DO NOT IMPLEMENT
139  public:
140    // allocate space for exactly one operand
141    void *operator new(size_t s) {
142      return User::operator new(s, 1);
143    }
144    explicit ConstantPlaceHolder(const Type *Ty, LLVMContext& Context)
145      : ConstantExpr(Ty, Instruction::UserOp1, &Op<0>(), 1) {
146      Op<0>() = UndefValue::get(Type::getInt32Ty(Context));
147    }
148
149    /// @brief Methods to support type inquiry through isa, cast, and dyn_cast.
150    static inline bool classof(const ConstantPlaceHolder *) { return true; }
151    static bool classof(const Value *V) {
152      return isa<ConstantExpr>(V) &&
153             cast<ConstantExpr>(V)->getOpcode() == Instruction::UserOp1;
154    }
155
156
157    /// Provide fast operand accessors
158    //DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
159  };
160}
161
162// FIXME: can we inherit this from ConstantExpr?
163template <>
164struct OperandTraits<ConstantPlaceHolder> : public FixedNumOperandTraits<1> {
165};
166}
167
168
169void BitcodeReaderValueList::AssignValue(Value *V, unsigned Idx) {
170  if (Idx == size()) {
171    push_back(V);
172    return;
173  }
174
175  if (Idx >= size())
176    resize(Idx+1);
177
178  WeakVH &OldV = ValuePtrs[Idx];
179  if (OldV == 0) {
180    OldV = V;
181    return;
182  }
183
184  // Handle constants and non-constants (e.g. instrs) differently for
185  // efficiency.
186  if (Constant *PHC = dyn_cast<Constant>(&*OldV)) {
187    ResolveConstants.push_back(std::make_pair(PHC, Idx));
188    OldV = V;
189  } else {
190    // If there was a forward reference to this value, replace it.
191    Value *PrevVal = OldV;
192    OldV->replaceAllUsesWith(V);
193    delete PrevVal;
194  }
195}
196
197
198Constant *BitcodeReaderValueList::getConstantFwdRef(unsigned Idx,
199                                                    const Type *Ty) {
200  if (Idx >= size())
201    resize(Idx + 1);
202
203  if (Value *V = ValuePtrs[Idx]) {
204    assert(Ty == V->getType() && "Type mismatch in constant table!");
205    return cast<Constant>(V);
206  }
207
208  // Create and return a placeholder, which will later be RAUW'd.
209  Constant *C = new ConstantPlaceHolder(Ty, Context);
210  ValuePtrs[Idx] = C;
211  return C;
212}
213
214Value *BitcodeReaderValueList::getValueFwdRef(unsigned Idx, const Type *Ty) {
215  if (Idx >= size())
216    resize(Idx + 1);
217
218  if (Value *V = ValuePtrs[Idx]) {
219    assert((Ty == 0 || Ty == V->getType()) && "Type mismatch in value table!");
220    return V;
221  }
222
223  // No type specified, must be invalid reference.
224  if (Ty == 0) return 0;
225
226  // Create and return a placeholder, which will later be RAUW'd.
227  Value *V = new Argument(Ty);
228  ValuePtrs[Idx] = V;
229  return V;
230}
231
232/// ResolveConstantForwardRefs - Once all constants are read, this method bulk
233/// resolves any forward references.  The idea behind this is that we sometimes
234/// get constants (such as large arrays) which reference *many* forward ref
235/// constants.  Replacing each of these causes a lot of thrashing when
236/// building/reuniquing the constant.  Instead of doing this, we look at all the
237/// uses and rewrite all the place holders at once for any constant that uses
238/// a placeholder.
239void BitcodeReaderValueList::ResolveConstantForwardRefs() {
240  // Sort the values by-pointer so that they are efficient to look up with a
241  // binary search.
242  std::sort(ResolveConstants.begin(), ResolveConstants.end());
243
244  SmallVector<Constant*, 64> NewOps;
245
246  while (!ResolveConstants.empty()) {
247    Value *RealVal = operator[](ResolveConstants.back().second);
248    Constant *Placeholder = ResolveConstants.back().first;
249    ResolveConstants.pop_back();
250
251    // Loop over all users of the placeholder, updating them to reference the
252    // new value.  If they reference more than one placeholder, update them all
253    // at once.
254    while (!Placeholder->use_empty()) {
255      Value::use_iterator UI = Placeholder->use_begin();
256
257      // If the using object isn't uniqued, just update the operands.  This
258      // handles instructions and initializers for global variables.
259      if (!isa<Constant>(*UI) || isa<GlobalValue>(*UI)) {
260        UI.getUse().set(RealVal);
261        continue;
262      }
263
264      // Otherwise, we have a constant that uses the placeholder.  Replace that
265      // constant with a new constant that has *all* placeholder uses updated.
266      Constant *UserC = cast<Constant>(*UI);
267      for (User::op_iterator I = UserC->op_begin(), E = UserC->op_end();
268           I != E; ++I) {
269        Value *NewOp;
270        if (!isa<ConstantPlaceHolder>(*I)) {
271          // Not a placeholder reference.
272          NewOp = *I;
273        } else if (*I == Placeholder) {
274          // Common case is that it just references this one placeholder.
275          NewOp = RealVal;
276        } else {
277          // Otherwise, look up the placeholder in ResolveConstants.
278          ResolveConstantsTy::iterator It =
279            std::lower_bound(ResolveConstants.begin(), ResolveConstants.end(),
280                             std::pair<Constant*, unsigned>(cast<Constant>(*I),
281                                                            0));
282          assert(It != ResolveConstants.end() && It->first == *I);
283          NewOp = operator[](It->second);
284        }
285
286        NewOps.push_back(cast<Constant>(NewOp));
287      }
288
289      // Make the new constant.
290      Constant *NewC;
291      if (ConstantArray *UserCA = dyn_cast<ConstantArray>(UserC)) {
292        NewC = ConstantArray::get(UserCA->getType(), &NewOps[0],
293                                        NewOps.size());
294      } else if (ConstantStruct *UserCS = dyn_cast<ConstantStruct>(UserC)) {
295        NewC = ConstantStruct::get(Context, &NewOps[0], NewOps.size(),
296                                         UserCS->getType()->isPacked());
297      } else if (isa<ConstantVector>(UserC)) {
298        NewC = ConstantVector::get(&NewOps[0], NewOps.size());
299      } else {
300        assert(isa<ConstantExpr>(UserC) && "Must be a ConstantExpr.");
301        NewC = cast<ConstantExpr>(UserC)->getWithOperands(&NewOps[0],
302                                                          NewOps.size());
303      }
304
305      UserC->replaceAllUsesWith(NewC);
306      UserC->destroyConstant();
307      NewOps.clear();
308    }
309
310    // Update all ValueHandles, they should be the only users at this point.
311    Placeholder->replaceAllUsesWith(RealVal);
312    delete Placeholder;
313  }
314}
315
316void BitcodeReaderMDValueList::AssignValue(Value *V, unsigned Idx) {
317  if (Idx == size()) {
318    push_back(V);
319    return;
320  }
321
322  if (Idx >= size())
323    resize(Idx+1);
324
325  WeakVH &OldV = MDValuePtrs[Idx];
326  if (OldV == 0) {
327    OldV = V;
328    return;
329  }
330
331  // If there was a forward reference to this value, replace it.
332  Value *PrevVal = OldV;
333  OldV->replaceAllUsesWith(V);
334  delete PrevVal;
335  // Deleting PrevVal sets Idx value in MDValuePtrs to null. Set new
336  // value for Idx.
337  MDValuePtrs[Idx] = V;
338}
339
340Value *BitcodeReaderMDValueList::getValueFwdRef(unsigned Idx) {
341  if (Idx >= size())
342    resize(Idx + 1);
343
344  if (Value *V = MDValuePtrs[Idx]) {
345    assert(V->getType()->isMetadataTy() && "Type mismatch in value table!");
346    return V;
347  }
348
349  // Create and return a placeholder, which will later be RAUW'd.
350  Value *V = new Argument(Type::getMetadataTy(Context));
351  MDValuePtrs[Idx] = V;
352  return V;
353}
354
355const Type *BitcodeReader::getTypeByID(unsigned ID, bool isTypeTable) {
356  // If the TypeID is in range, return it.
357  if (ID < TypeList.size())
358    return TypeList[ID].get();
359  if (!isTypeTable) return 0;
360
361  // The type table allows forward references.  Push as many Opaque types as
362  // needed to get up to ID.
363  while (TypeList.size() <= ID)
364    TypeList.push_back(OpaqueType::get(Context));
365  return TypeList.back().get();
366}
367
368//===----------------------------------------------------------------------===//
369//  Functions for parsing blocks from the bitcode file
370//===----------------------------------------------------------------------===//
371
372bool BitcodeReader::ParseAttributeBlock() {
373  if (Stream.EnterSubBlock(bitc::PARAMATTR_BLOCK_ID))
374    return Error("Malformed block record");
375
376  if (!MAttributes.empty())
377    return Error("Multiple PARAMATTR blocks found!");
378
379  SmallVector<uint64_t, 64> Record;
380
381  SmallVector<AttributeWithIndex, 8> Attrs;
382
383  // Read all the records.
384  while (1) {
385    unsigned Code = Stream.ReadCode();
386    if (Code == bitc::END_BLOCK) {
387      if (Stream.ReadBlockEnd())
388        return Error("Error at end of PARAMATTR block");
389      return false;
390    }
391
392    if (Code == bitc::ENTER_SUBBLOCK) {
393      // No known subblocks, always skip them.
394      Stream.ReadSubBlockID();
395      if (Stream.SkipBlock())
396        return Error("Malformed block record");
397      continue;
398    }
399
400    if (Code == bitc::DEFINE_ABBREV) {
401      Stream.ReadAbbrevRecord();
402      continue;
403    }
404
405    // Read a record.
406    Record.clear();
407    switch (Stream.ReadRecord(Code, Record)) {
408    default:  // Default behavior: ignore.
409      break;
410    case bitc::PARAMATTR_CODE_ENTRY: { // ENTRY: [paramidx0, attr0, ...]
411      if (Record.size() & 1)
412        return Error("Invalid ENTRY record");
413
414      // FIXME : Remove this autoupgrade code in LLVM 3.0.
415      // If Function attributes are using index 0 then transfer them
416      // to index ~0. Index 0 is used for return value attributes but used to be
417      // used for function attributes.
418      Attributes RetAttribute = Attribute::None;
419      Attributes FnAttribute = Attribute::None;
420      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
421        // FIXME: remove in LLVM 3.0
422        // The alignment is stored as a 16-bit raw value from bits 31--16.
423        // We shift the bits above 31 down by 11 bits.
424
425        unsigned Alignment = (Record[i+1] & (0xffffull << 16)) >> 16;
426        if (Alignment && !isPowerOf2_32(Alignment))
427          return Error("Alignment is not a power of two.");
428
429        Attributes ReconstitutedAttr = Record[i+1] & 0xffff;
430        if (Alignment)
431          ReconstitutedAttr |= Attribute::constructAlignmentFromInt(Alignment);
432        ReconstitutedAttr |= (Record[i+1] & (0xffffull << 32)) >> 11;
433        Record[i+1] = ReconstitutedAttr;
434
435        if (Record[i] == 0)
436          RetAttribute = Record[i+1];
437        else if (Record[i] == ~0U)
438          FnAttribute = Record[i+1];
439      }
440
441      unsigned OldRetAttrs = (Attribute::NoUnwind|Attribute::NoReturn|
442                              Attribute::ReadOnly|Attribute::ReadNone);
443
444      if (FnAttribute == Attribute::None && RetAttribute != Attribute::None &&
445          (RetAttribute & OldRetAttrs) != 0) {
446        if (FnAttribute == Attribute::None) { // add a slot so they get added.
447          Record.push_back(~0U);
448          Record.push_back(0);
449        }
450
451        FnAttribute  |= RetAttribute & OldRetAttrs;
452        RetAttribute &= ~OldRetAttrs;
453      }
454
455      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
456        if (Record[i] == 0) {
457          if (RetAttribute != Attribute::None)
458            Attrs.push_back(AttributeWithIndex::get(0, RetAttribute));
459        } else if (Record[i] == ~0U) {
460          if (FnAttribute != Attribute::None)
461            Attrs.push_back(AttributeWithIndex::get(~0U, FnAttribute));
462        } else if (Record[i+1] != Attribute::None)
463          Attrs.push_back(AttributeWithIndex::get(Record[i], Record[i+1]));
464      }
465
466      MAttributes.push_back(AttrListPtr::get(Attrs.begin(), Attrs.end()));
467      Attrs.clear();
468      break;
469    }
470    }
471  }
472}
473
474
475bool BitcodeReader::ParseTypeTable() {
476  if (Stream.EnterSubBlock(bitc::TYPE_BLOCK_ID))
477    return Error("Malformed block record");
478
479  if (!TypeList.empty())
480    return Error("Multiple TYPE_BLOCKs found!");
481
482  SmallVector<uint64_t, 64> Record;
483  unsigned NumRecords = 0;
484
485  // Read all the records for this type table.
486  while (1) {
487    unsigned Code = Stream.ReadCode();
488    if (Code == bitc::END_BLOCK) {
489      if (NumRecords != TypeList.size())
490        return Error("Invalid type forward reference in TYPE_BLOCK");
491      if (Stream.ReadBlockEnd())
492        return Error("Error at end of type table block");
493      return false;
494    }
495
496    if (Code == bitc::ENTER_SUBBLOCK) {
497      // No known subblocks, always skip them.
498      Stream.ReadSubBlockID();
499      if (Stream.SkipBlock())
500        return Error("Malformed block record");
501      continue;
502    }
503
504    if (Code == bitc::DEFINE_ABBREV) {
505      Stream.ReadAbbrevRecord();
506      continue;
507    }
508
509    // Read a record.
510    Record.clear();
511    const Type *ResultTy = 0;
512    switch (Stream.ReadRecord(Code, Record)) {
513    default:  // Default behavior: unknown type.
514      ResultTy = 0;
515      break;
516    case bitc::TYPE_CODE_NUMENTRY: // TYPE_CODE_NUMENTRY: [numentries]
517      // TYPE_CODE_NUMENTRY contains a count of the number of types in the
518      // type list.  This allows us to reserve space.
519      if (Record.size() < 1)
520        return Error("Invalid TYPE_CODE_NUMENTRY record");
521      TypeList.reserve(Record[0]);
522      continue;
523    case bitc::TYPE_CODE_VOID:      // VOID
524      ResultTy = Type::getVoidTy(Context);
525      break;
526    case bitc::TYPE_CODE_FLOAT:     // FLOAT
527      ResultTy = Type::getFloatTy(Context);
528      break;
529    case bitc::TYPE_CODE_DOUBLE:    // DOUBLE
530      ResultTy = Type::getDoubleTy(Context);
531      break;
532    case bitc::TYPE_CODE_X86_FP80:  // X86_FP80
533      ResultTy = Type::getX86_FP80Ty(Context);
534      break;
535    case bitc::TYPE_CODE_FP128:     // FP128
536      ResultTy = Type::getFP128Ty(Context);
537      break;
538    case bitc::TYPE_CODE_PPC_FP128: // PPC_FP128
539      ResultTy = Type::getPPC_FP128Ty(Context);
540      break;
541    case bitc::TYPE_CODE_LABEL:     // LABEL
542      ResultTy = Type::getLabelTy(Context);
543      break;
544    case bitc::TYPE_CODE_OPAQUE:    // OPAQUE
545      ResultTy = 0;
546      break;
547    case bitc::TYPE_CODE_METADATA:  // METADATA
548      ResultTy = Type::getMetadataTy(Context);
549      break;
550    case bitc::TYPE_CODE_INTEGER:   // INTEGER: [width]
551      if (Record.size() < 1)
552        return Error("Invalid Integer type record");
553
554      ResultTy = IntegerType::get(Context, Record[0]);
555      break;
556    case bitc::TYPE_CODE_POINTER: { // POINTER: [pointee type] or
557                                    //          [pointee type, address space]
558      if (Record.size() < 1)
559        return Error("Invalid POINTER type record");
560      unsigned AddressSpace = 0;
561      if (Record.size() == 2)
562        AddressSpace = Record[1];
563      ResultTy = PointerType::get(getTypeByID(Record[0], true),
564                                        AddressSpace);
565      break;
566    }
567    case bitc::TYPE_CODE_FUNCTION: {
568      // FIXME: attrid is dead, remove it in LLVM 3.0
569      // FUNCTION: [vararg, attrid, retty, paramty x N]
570      if (Record.size() < 3)
571        return Error("Invalid FUNCTION type record");
572      std::vector<const Type*> ArgTys;
573      for (unsigned i = 3, e = Record.size(); i != e; ++i)
574        ArgTys.push_back(getTypeByID(Record[i], true));
575
576      ResultTy = FunctionType::get(getTypeByID(Record[2], true), ArgTys,
577                                   Record[0]);
578      break;
579    }
580    case bitc::TYPE_CODE_STRUCT: {  // STRUCT: [ispacked, eltty x N]
581      if (Record.size() < 1)
582        return Error("Invalid STRUCT type record");
583      std::vector<const Type*> EltTys;
584      for (unsigned i = 1, e = Record.size(); i != e; ++i)
585        EltTys.push_back(getTypeByID(Record[i], true));
586      ResultTy = StructType::get(Context, EltTys, Record[0]);
587      break;
588    }
589    case bitc::TYPE_CODE_ARRAY:     // ARRAY: [numelts, eltty]
590      if (Record.size() < 2)
591        return Error("Invalid ARRAY type record");
592      ResultTy = ArrayType::get(getTypeByID(Record[1], true), Record[0]);
593      break;
594    case bitc::TYPE_CODE_VECTOR:    // VECTOR: [numelts, eltty]
595      if (Record.size() < 2)
596        return Error("Invalid VECTOR type record");
597      ResultTy = VectorType::get(getTypeByID(Record[1], true), Record[0]);
598      break;
599    }
600
601    if (NumRecords == TypeList.size()) {
602      // If this is a new type slot, just append it.
603      TypeList.push_back(ResultTy ? ResultTy : OpaqueType::get(Context));
604      ++NumRecords;
605    } else if (ResultTy == 0) {
606      // Otherwise, this was forward referenced, so an opaque type was created,
607      // but the result type is actually just an opaque.  Leave the one we
608      // created previously.
609      ++NumRecords;
610    } else {
611      // Otherwise, this was forward referenced, so an opaque type was created.
612      // Resolve the opaque type to the real type now.
613      assert(NumRecords < TypeList.size() && "Typelist imbalance");
614      const OpaqueType *OldTy = cast<OpaqueType>(TypeList[NumRecords++].get());
615
616      // Don't directly push the new type on the Tab. Instead we want to replace
617      // the opaque type we previously inserted with the new concrete value. The
618      // refinement from the abstract (opaque) type to the new type causes all
619      // uses of the abstract type to use the concrete type (NewTy). This will
620      // also cause the opaque type to be deleted.
621      const_cast<OpaqueType*>(OldTy)->refineAbstractTypeTo(ResultTy);
622
623      // This should have replaced the old opaque type with the new type in the
624      // value table... or with a preexisting type that was already in the
625      // system.  Let's just make sure it did.
626      assert(TypeList[NumRecords-1].get() != OldTy &&
627             "refineAbstractType didn't work!");
628    }
629  }
630}
631
632
633bool BitcodeReader::ParseTypeSymbolTable() {
634  if (Stream.EnterSubBlock(bitc::TYPE_SYMTAB_BLOCK_ID))
635    return Error("Malformed block record");
636
637  SmallVector<uint64_t, 64> Record;
638
639  // Read all the records for this type table.
640  std::string TypeName;
641  while (1) {
642    unsigned Code = Stream.ReadCode();
643    if (Code == bitc::END_BLOCK) {
644      if (Stream.ReadBlockEnd())
645        return Error("Error at end of type symbol table block");
646      return false;
647    }
648
649    if (Code == bitc::ENTER_SUBBLOCK) {
650      // No known subblocks, always skip them.
651      Stream.ReadSubBlockID();
652      if (Stream.SkipBlock())
653        return Error("Malformed block record");
654      continue;
655    }
656
657    if (Code == bitc::DEFINE_ABBREV) {
658      Stream.ReadAbbrevRecord();
659      continue;
660    }
661
662    // Read a record.
663    Record.clear();
664    switch (Stream.ReadRecord(Code, Record)) {
665    default:  // Default behavior: unknown type.
666      break;
667    case bitc::TST_CODE_ENTRY:    // TST_ENTRY: [typeid, namechar x N]
668      if (ConvertToString(Record, 1, TypeName))
669        return Error("Invalid TST_ENTRY record");
670      unsigned TypeID = Record[0];
671      if (TypeID >= TypeList.size())
672        return Error("Invalid Type ID in TST_ENTRY record");
673
674      TheModule->addTypeName(TypeName, TypeList[TypeID].get());
675      TypeName.clear();
676      break;
677    }
678  }
679}
680
681bool BitcodeReader::ParseValueSymbolTable() {
682  if (Stream.EnterSubBlock(bitc::VALUE_SYMTAB_BLOCK_ID))
683    return Error("Malformed block record");
684
685  SmallVector<uint64_t, 64> Record;
686
687  // Read all the records for this value table.
688  SmallString<128> ValueName;
689  while (1) {
690    unsigned Code = Stream.ReadCode();
691    if (Code == bitc::END_BLOCK) {
692      if (Stream.ReadBlockEnd())
693        return Error("Error at end of value symbol table block");
694      return false;
695    }
696    if (Code == bitc::ENTER_SUBBLOCK) {
697      // No known subblocks, always skip them.
698      Stream.ReadSubBlockID();
699      if (Stream.SkipBlock())
700        return Error("Malformed block record");
701      continue;
702    }
703
704    if (Code == bitc::DEFINE_ABBREV) {
705      Stream.ReadAbbrevRecord();
706      continue;
707    }
708
709    // Read a record.
710    Record.clear();
711    switch (Stream.ReadRecord(Code, Record)) {
712    default:  // Default behavior: unknown type.
713      break;
714    case bitc::VST_CODE_ENTRY: {  // VST_ENTRY: [valueid, namechar x N]
715      if (ConvertToString(Record, 1, ValueName))
716        return Error("Invalid VST_ENTRY record");
717      unsigned ValueID = Record[0];
718      if (ValueID >= ValueList.size())
719        return Error("Invalid Value ID in VST_ENTRY record");
720      Value *V = ValueList[ValueID];
721
722      V->setName(StringRef(ValueName.data(), ValueName.size()));
723      ValueName.clear();
724      break;
725    }
726    case bitc::VST_CODE_BBENTRY: {
727      if (ConvertToString(Record, 1, ValueName))
728        return Error("Invalid VST_BBENTRY record");
729      BasicBlock *BB = getBasicBlock(Record[0]);
730      if (BB == 0)
731        return Error("Invalid BB ID in VST_BBENTRY record");
732
733      BB->setName(StringRef(ValueName.data(), ValueName.size()));
734      ValueName.clear();
735      break;
736    }
737    }
738  }
739}
740
741bool BitcodeReader::ParseMetadata() {
742  unsigned NextValueNo = MDValueList.size();
743
744  if (Stream.EnterSubBlock(bitc::METADATA_BLOCK_ID))
745    return Error("Malformed block record");
746
747  SmallVector<uint64_t, 64> Record;
748
749  // Read all the records.
750  while (1) {
751    unsigned Code = Stream.ReadCode();
752    if (Code == bitc::END_BLOCK) {
753      if (Stream.ReadBlockEnd())
754        return Error("Error at end of PARAMATTR block");
755      return false;
756    }
757
758    if (Code == bitc::ENTER_SUBBLOCK) {
759      // No known subblocks, always skip them.
760      Stream.ReadSubBlockID();
761      if (Stream.SkipBlock())
762        return Error("Malformed block record");
763      continue;
764    }
765
766    if (Code == bitc::DEFINE_ABBREV) {
767      Stream.ReadAbbrevRecord();
768      continue;
769    }
770
771    // Read a record.
772    Record.clear();
773    switch (Stream.ReadRecord(Code, Record)) {
774    default:  // Default behavior: ignore.
775      break;
776    case bitc::METADATA_NAME: {
777      // Read named of the named metadata.
778      unsigned NameLength = Record.size();
779      SmallString<8> Name;
780      Name.resize(NameLength);
781      for (unsigned i = 0; i != NameLength; ++i)
782        Name[i] = Record[i];
783      Record.clear();
784      Code = Stream.ReadCode();
785
786      // METADATA_NAME is always followed by METADATA_NAMED_NODE.
787      if (Stream.ReadRecord(Code, Record) != bitc::METADATA_NAMED_NODE)
788        assert ( 0 && "Inavlid Named Metadata record");
789
790      // Read named metadata elements.
791      unsigned Size = Record.size();
792      SmallVector<MetadataBase*, 8> Elts;
793      for (unsigned i = 0; i != Size; ++i) {
794        Value *MD = MDValueList.getValueFwdRef(Record[i]);
795        if (MetadataBase *B = dyn_cast<MetadataBase>(MD))
796        Elts.push_back(B);
797      }
798      Value *V = NamedMDNode::Create(Context, Name.str(), Elts.data(),
799                                     Elts.size(), TheModule);
800      MDValueList.AssignValue(V, NextValueNo++);
801      break;
802    }
803    case bitc::METADATA_NODE: {
804      if (Record.empty() || Record.size() % 2 == 1)
805        return Error("Invalid METADATA_NODE record");
806
807      unsigned Size = Record.size();
808      SmallVector<Value*, 8> Elts;
809      for (unsigned i = 0; i != Size; i += 2) {
810        const Type *Ty = getTypeByID(Record[i], false);
811        if (Ty->isMetadataTy())
812          Elts.push_back(MDValueList.getValueFwdRef(Record[i+1]));
813        else if (Ty != Type::getVoidTy(Context))
814          Elts.push_back(ValueList.getValueFwdRef(Record[i+1], Ty));
815        else
816          Elts.push_back(NULL);
817      }
818      Value *V = MDNode::get(Context, &Elts[0], Elts.size());
819      MDValueList.AssignValue(V, NextValueNo++);
820      break;
821    }
822    case bitc::METADATA_STRING: {
823      unsigned MDStringLength = Record.size();
824      SmallString<8> String;
825      String.resize(MDStringLength);
826      for (unsigned i = 0; i != MDStringLength; ++i)
827        String[i] = Record[i];
828      Value *V = MDString::get(Context,
829                               StringRef(String.data(), String.size()));
830      MDValueList.AssignValue(V, NextValueNo++);
831      break;
832    }
833    case bitc::METADATA_KIND: {
834      unsigned RecordLength = Record.size();
835      if (Record.empty() || RecordLength < 2)
836        return Error("Invalid METADATA_KIND record");
837      SmallString<8> Name;
838      Name.resize(RecordLength-1);
839      unsigned Kind = Record[0];
840      for (unsigned i = 1; i != RecordLength; ++i)
841        Name[i-1] = Record[i];
842      MetadataContext &TheMetadata = Context.getMetadata();
843      TheMetadata.MDHandlerNames[Name.str()] = Kind;
844      break;
845    }
846    }
847  }
848}
849
850/// DecodeSignRotatedValue - Decode a signed value stored with the sign bit in
851/// the LSB for dense VBR encoding.
852static uint64_t DecodeSignRotatedValue(uint64_t V) {
853  if ((V & 1) == 0)
854    return V >> 1;
855  if (V != 1)
856    return -(V >> 1);
857  // There is no such thing as -0 with integers.  "-0" really means MININT.
858  return 1ULL << 63;
859}
860
861/// ResolveGlobalAndAliasInits - Resolve all of the initializers for global
862/// values and aliases that we can.
863bool BitcodeReader::ResolveGlobalAndAliasInits() {
864  std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInitWorklist;
865  std::vector<std::pair<GlobalAlias*, unsigned> > AliasInitWorklist;
866
867  GlobalInitWorklist.swap(GlobalInits);
868  AliasInitWorklist.swap(AliasInits);
869
870  while (!GlobalInitWorklist.empty()) {
871    unsigned ValID = GlobalInitWorklist.back().second;
872    if (ValID >= ValueList.size()) {
873      // Not ready to resolve this yet, it requires something later in the file.
874      GlobalInits.push_back(GlobalInitWorklist.back());
875    } else {
876      if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
877        GlobalInitWorklist.back().first->setInitializer(C);
878      else
879        return Error("Global variable initializer is not a constant!");
880    }
881    GlobalInitWorklist.pop_back();
882  }
883
884  while (!AliasInitWorklist.empty()) {
885    unsigned ValID = AliasInitWorklist.back().second;
886    if (ValID >= ValueList.size()) {
887      AliasInits.push_back(AliasInitWorklist.back());
888    } else {
889      if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
890        AliasInitWorklist.back().first->setAliasee(C);
891      else
892        return Error("Alias initializer is not a constant!");
893    }
894    AliasInitWorklist.pop_back();
895  }
896  return false;
897}
898
899bool BitcodeReader::ParseConstants() {
900  if (Stream.EnterSubBlock(bitc::CONSTANTS_BLOCK_ID))
901    return Error("Malformed block record");
902
903  SmallVector<uint64_t, 64> Record;
904
905  // Read all the records for this value table.
906  const Type *CurTy = Type::getInt32Ty(Context);
907  unsigned NextCstNo = ValueList.size();
908  while (1) {
909    unsigned Code = Stream.ReadCode();
910    if (Code == bitc::END_BLOCK)
911      break;
912
913    if (Code == bitc::ENTER_SUBBLOCK) {
914      // No known subblocks, always skip them.
915      Stream.ReadSubBlockID();
916      if (Stream.SkipBlock())
917        return Error("Malformed block record");
918      continue;
919    }
920
921    if (Code == bitc::DEFINE_ABBREV) {
922      Stream.ReadAbbrevRecord();
923      continue;
924    }
925
926    // Read a record.
927    Record.clear();
928    Value *V = 0;
929    unsigned BitCode = Stream.ReadRecord(Code, Record);
930    switch (BitCode) {
931    default:  // Default behavior: unknown constant
932    case bitc::CST_CODE_UNDEF:     // UNDEF
933      V = UndefValue::get(CurTy);
934      break;
935    case bitc::CST_CODE_SETTYPE:   // SETTYPE: [typeid]
936      if (Record.empty())
937        return Error("Malformed CST_SETTYPE record");
938      if (Record[0] >= TypeList.size())
939        return Error("Invalid Type ID in CST_SETTYPE record");
940      CurTy = TypeList[Record[0]];
941      continue;  // Skip the ValueList manipulation.
942    case bitc::CST_CODE_NULL:      // NULL
943      V = Constant::getNullValue(CurTy);
944      break;
945    case bitc::CST_CODE_INTEGER:   // INTEGER: [intval]
946      if (!isa<IntegerType>(CurTy) || Record.empty())
947        return Error("Invalid CST_INTEGER record");
948      V = ConstantInt::get(CurTy, DecodeSignRotatedValue(Record[0]));
949      break;
950    case bitc::CST_CODE_WIDE_INTEGER: {// WIDE_INTEGER: [n x intval]
951      if (!isa<IntegerType>(CurTy) || Record.empty())
952        return Error("Invalid WIDE_INTEGER record");
953
954      unsigned NumWords = Record.size();
955      SmallVector<uint64_t, 8> Words;
956      Words.resize(NumWords);
957      for (unsigned i = 0; i != NumWords; ++i)
958        Words[i] = DecodeSignRotatedValue(Record[i]);
959      V = ConstantInt::get(Context,
960                           APInt(cast<IntegerType>(CurTy)->getBitWidth(),
961                           NumWords, &Words[0]));
962      break;
963    }
964    case bitc::CST_CODE_FLOAT: {    // FLOAT: [fpval]
965      if (Record.empty())
966        return Error("Invalid FLOAT record");
967      if (CurTy->isFloatTy())
968        V = ConstantFP::get(Context, APFloat(APInt(32, (uint32_t)Record[0])));
969      else if (CurTy->isDoubleTy())
970        V = ConstantFP::get(Context, APFloat(APInt(64, Record[0])));
971      else if (CurTy->isX86_FP80Ty()) {
972        // Bits are not stored the same way as a normal i80 APInt, compensate.
973        uint64_t Rearrange[2];
974        Rearrange[0] = (Record[1] & 0xffffLL) | (Record[0] << 16);
975        Rearrange[1] = Record[0] >> 48;
976        V = ConstantFP::get(Context, APFloat(APInt(80, 2, Rearrange)));
977      } else if (CurTy->isFP128Ty())
978        V = ConstantFP::get(Context, APFloat(APInt(128, 2, &Record[0]), true));
979      else if (CurTy->isPPC_FP128Ty())
980        V = ConstantFP::get(Context, APFloat(APInt(128, 2, &Record[0])));
981      else
982        V = UndefValue::get(CurTy);
983      break;
984    }
985
986    case bitc::CST_CODE_AGGREGATE: {// AGGREGATE: [n x value number]
987      if (Record.empty())
988        return Error("Invalid CST_AGGREGATE record");
989
990      unsigned Size = Record.size();
991      std::vector<Constant*> Elts;
992
993      if (const StructType *STy = dyn_cast<StructType>(CurTy)) {
994        for (unsigned i = 0; i != Size; ++i)
995          Elts.push_back(ValueList.getConstantFwdRef(Record[i],
996                                                     STy->getElementType(i)));
997        V = ConstantStruct::get(STy, Elts);
998      } else if (const ArrayType *ATy = dyn_cast<ArrayType>(CurTy)) {
999        const Type *EltTy = ATy->getElementType();
1000        for (unsigned i = 0; i != Size; ++i)
1001          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
1002        V = ConstantArray::get(ATy, Elts);
1003      } else if (const VectorType *VTy = dyn_cast<VectorType>(CurTy)) {
1004        const Type *EltTy = VTy->getElementType();
1005        for (unsigned i = 0; i != Size; ++i)
1006          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
1007        V = ConstantVector::get(Elts);
1008      } else {
1009        V = UndefValue::get(CurTy);
1010      }
1011      break;
1012    }
1013    case bitc::CST_CODE_STRING: { // STRING: [values]
1014      if (Record.empty())
1015        return Error("Invalid CST_AGGREGATE record");
1016
1017      const ArrayType *ATy = cast<ArrayType>(CurTy);
1018      const Type *EltTy = ATy->getElementType();
1019
1020      unsigned Size = Record.size();
1021      std::vector<Constant*> Elts;
1022      for (unsigned i = 0; i != Size; ++i)
1023        Elts.push_back(ConstantInt::get(EltTy, Record[i]));
1024      V = ConstantArray::get(ATy, Elts);
1025      break;
1026    }
1027    case bitc::CST_CODE_CSTRING: { // CSTRING: [values]
1028      if (Record.empty())
1029        return Error("Invalid CST_AGGREGATE record");
1030
1031      const ArrayType *ATy = cast<ArrayType>(CurTy);
1032      const Type *EltTy = ATy->getElementType();
1033
1034      unsigned Size = Record.size();
1035      std::vector<Constant*> Elts;
1036      for (unsigned i = 0; i != Size; ++i)
1037        Elts.push_back(ConstantInt::get(EltTy, Record[i]));
1038      Elts.push_back(Constant::getNullValue(EltTy));
1039      V = ConstantArray::get(ATy, Elts);
1040      break;
1041    }
1042    case bitc::CST_CODE_CE_BINOP: {  // CE_BINOP: [opcode, opval, opval]
1043      if (Record.size() < 3) return Error("Invalid CE_BINOP record");
1044      int Opc = GetDecodedBinaryOpcode(Record[0], CurTy);
1045      if (Opc < 0) {
1046        V = UndefValue::get(CurTy);  // Unknown binop.
1047      } else {
1048        Constant *LHS = ValueList.getConstantFwdRef(Record[1], CurTy);
1049        Constant *RHS = ValueList.getConstantFwdRef(Record[2], CurTy);
1050        unsigned Flags = 0;
1051        if (Record.size() >= 4) {
1052          if (Opc == Instruction::Add ||
1053              Opc == Instruction::Sub ||
1054              Opc == Instruction::Mul) {
1055            if (Record[3] & (1 << bitc::OBO_NO_SIGNED_WRAP))
1056              Flags |= OverflowingBinaryOperator::NoSignedWrap;
1057            if (Record[3] & (1 << bitc::OBO_NO_UNSIGNED_WRAP))
1058              Flags |= OverflowingBinaryOperator::NoUnsignedWrap;
1059          } else if (Opc == Instruction::SDiv) {
1060            if (Record[3] & (1 << bitc::SDIV_EXACT))
1061              Flags |= SDivOperator::IsExact;
1062          }
1063        }
1064        V = ConstantExpr::get(Opc, LHS, RHS, Flags);
1065      }
1066      break;
1067    }
1068    case bitc::CST_CODE_CE_CAST: {  // CE_CAST: [opcode, opty, opval]
1069      if (Record.size() < 3) return Error("Invalid CE_CAST record");
1070      int Opc = GetDecodedCastOpcode(Record[0]);
1071      if (Opc < 0) {
1072        V = UndefValue::get(CurTy);  // Unknown cast.
1073      } else {
1074        const Type *OpTy = getTypeByID(Record[1]);
1075        if (!OpTy) return Error("Invalid CE_CAST record");
1076        Constant *Op = ValueList.getConstantFwdRef(Record[2], OpTy);
1077        V = ConstantExpr::getCast(Opc, Op, CurTy);
1078      }
1079      break;
1080    }
1081    case bitc::CST_CODE_CE_INBOUNDS_GEP:
1082    case bitc::CST_CODE_CE_GEP: {  // CE_GEP:        [n x operands]
1083      if (Record.size() & 1) return Error("Invalid CE_GEP record");
1084      SmallVector<Constant*, 16> Elts;
1085      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
1086        const Type *ElTy = getTypeByID(Record[i]);
1087        if (!ElTy) return Error("Invalid CE_GEP record");
1088        Elts.push_back(ValueList.getConstantFwdRef(Record[i+1], ElTy));
1089      }
1090      if (BitCode == bitc::CST_CODE_CE_INBOUNDS_GEP)
1091        V = ConstantExpr::getInBoundsGetElementPtr(Elts[0], &Elts[1],
1092                                                   Elts.size()-1);
1093      else
1094        V = ConstantExpr::getGetElementPtr(Elts[0], &Elts[1],
1095                                           Elts.size()-1);
1096      break;
1097    }
1098    case bitc::CST_CODE_CE_SELECT:  // CE_SELECT: [opval#, opval#, opval#]
1099      if (Record.size() < 3) return Error("Invalid CE_SELECT record");
1100      V = ConstantExpr::getSelect(ValueList.getConstantFwdRef(Record[0],
1101                                                              Type::getInt1Ty(Context)),
1102                                  ValueList.getConstantFwdRef(Record[1],CurTy),
1103                                  ValueList.getConstantFwdRef(Record[2],CurTy));
1104      break;
1105    case bitc::CST_CODE_CE_EXTRACTELT: { // CE_EXTRACTELT: [opty, opval, opval]
1106      if (Record.size() < 3) return Error("Invalid CE_EXTRACTELT record");
1107      const VectorType *OpTy =
1108        dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
1109      if (OpTy == 0) return Error("Invalid CE_EXTRACTELT record");
1110      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1111      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], Type::getInt32Ty(Context));
1112      V = ConstantExpr::getExtractElement(Op0, Op1);
1113      break;
1114    }
1115    case bitc::CST_CODE_CE_INSERTELT: { // CE_INSERTELT: [opval, opval, opval]
1116      const VectorType *OpTy = dyn_cast<VectorType>(CurTy);
1117      if (Record.size() < 3 || OpTy == 0)
1118        return Error("Invalid CE_INSERTELT record");
1119      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
1120      Constant *Op1 = ValueList.getConstantFwdRef(Record[1],
1121                                                  OpTy->getElementType());
1122      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], Type::getInt32Ty(Context));
1123      V = ConstantExpr::getInsertElement(Op0, Op1, Op2);
1124      break;
1125    }
1126    case bitc::CST_CODE_CE_SHUFFLEVEC: { // CE_SHUFFLEVEC: [opval, opval, opval]
1127      const VectorType *OpTy = dyn_cast<VectorType>(CurTy);
1128      if (Record.size() < 3 || OpTy == 0)
1129        return Error("Invalid CE_SHUFFLEVEC record");
1130      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
1131      Constant *Op1 = ValueList.getConstantFwdRef(Record[1], OpTy);
1132      const Type *ShufTy = VectorType::get(Type::getInt32Ty(Context),
1133                                                 OpTy->getNumElements());
1134      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], ShufTy);
1135      V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
1136      break;
1137    }
1138    case bitc::CST_CODE_CE_SHUFVEC_EX: { // [opty, opval, opval, opval]
1139      const VectorType *RTy = dyn_cast<VectorType>(CurTy);
1140      const VectorType *OpTy = dyn_cast<VectorType>(getTypeByID(Record[0]));
1141      if (Record.size() < 4 || RTy == 0 || OpTy == 0)
1142        return Error("Invalid CE_SHUFVEC_EX record");
1143      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1144      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
1145      const Type *ShufTy = VectorType::get(Type::getInt32Ty(Context),
1146                                                 RTy->getNumElements());
1147      Constant *Op2 = ValueList.getConstantFwdRef(Record[3], ShufTy);
1148      V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
1149      break;
1150    }
1151    case bitc::CST_CODE_CE_CMP: {     // CE_CMP: [opty, opval, opval, pred]
1152      if (Record.size() < 4) return Error("Invalid CE_CMP record");
1153      const Type *OpTy = getTypeByID(Record[0]);
1154      if (OpTy == 0) return Error("Invalid CE_CMP record");
1155      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1156      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
1157
1158      if (OpTy->isFloatingPoint())
1159        V = ConstantExpr::getFCmp(Record[3], Op0, Op1);
1160      else
1161        V = ConstantExpr::getICmp(Record[3], Op0, Op1);
1162      break;
1163    }
1164    case bitc::CST_CODE_INLINEASM: {
1165      if (Record.size() < 2) return Error("Invalid INLINEASM record");
1166      std::string AsmStr, ConstrStr;
1167      bool HasSideEffects = Record[0] & 1;
1168      bool IsAlignStack = Record[0] >> 1;
1169      unsigned AsmStrSize = Record[1];
1170      if (2+AsmStrSize >= Record.size())
1171        return Error("Invalid INLINEASM record");
1172      unsigned ConstStrSize = Record[2+AsmStrSize];
1173      if (3+AsmStrSize+ConstStrSize > Record.size())
1174        return Error("Invalid INLINEASM record");
1175
1176      for (unsigned i = 0; i != AsmStrSize; ++i)
1177        AsmStr += (char)Record[2+i];
1178      for (unsigned i = 0; i != ConstStrSize; ++i)
1179        ConstrStr += (char)Record[3+AsmStrSize+i];
1180      const PointerType *PTy = cast<PointerType>(CurTy);
1181      V = InlineAsm::get(cast<FunctionType>(PTy->getElementType()),
1182                         AsmStr, ConstrStr, HasSideEffects, IsAlignStack);
1183      break;
1184    }
1185    }
1186
1187    ValueList.AssignValue(V, NextCstNo);
1188    ++NextCstNo;
1189  }
1190
1191  if (NextCstNo != ValueList.size())
1192    return Error("Invalid constant reference!");
1193
1194  if (Stream.ReadBlockEnd())
1195    return Error("Error at end of constants block");
1196
1197  // Once all the constants have been read, go through and resolve forward
1198  // references.
1199  ValueList.ResolveConstantForwardRefs();
1200  return false;
1201}
1202
1203/// RememberAndSkipFunctionBody - When we see the block for a function body,
1204/// remember where it is and then skip it.  This lets us lazily deserialize the
1205/// functions.
1206bool BitcodeReader::RememberAndSkipFunctionBody() {
1207  // Get the function we are talking about.
1208  if (FunctionsWithBodies.empty())
1209    return Error("Insufficient function protos");
1210
1211  Function *Fn = FunctionsWithBodies.back();
1212  FunctionsWithBodies.pop_back();
1213
1214  // Save the current stream state.
1215  uint64_t CurBit = Stream.GetCurrentBitNo();
1216  DeferredFunctionInfo[Fn] = std::make_pair(CurBit, Fn->getLinkage());
1217
1218  // Set the functions linkage to GhostLinkage so we know it is lazily
1219  // deserialized.
1220  Fn->setLinkage(GlobalValue::GhostLinkage);
1221
1222  // Skip over the function block for now.
1223  if (Stream.SkipBlock())
1224    return Error("Malformed block record");
1225  return false;
1226}
1227
1228bool BitcodeReader::ParseModule(const std::string &ModuleID) {
1229  // Reject multiple MODULE_BLOCK's in a single bitstream.
1230  if (TheModule)
1231    return Error("Multiple MODULE_BLOCKs in same stream");
1232
1233  if (Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
1234    return Error("Malformed block record");
1235
1236  // Otherwise, create the module.
1237  TheModule = new Module(ModuleID, Context);
1238
1239  SmallVector<uint64_t, 64> Record;
1240  std::vector<std::string> SectionTable;
1241  std::vector<std::string> GCTable;
1242
1243  // Read all the records for this module.
1244  while (!Stream.AtEndOfStream()) {
1245    unsigned Code = Stream.ReadCode();
1246    if (Code == bitc::END_BLOCK) {
1247      if (Stream.ReadBlockEnd())
1248        return Error("Error at end of module block");
1249
1250      // Patch the initializers for globals and aliases up.
1251      ResolveGlobalAndAliasInits();
1252      if (!GlobalInits.empty() || !AliasInits.empty())
1253        return Error("Malformed global initializer set");
1254      if (!FunctionsWithBodies.empty())
1255        return Error("Too few function bodies found");
1256
1257      // Look for intrinsic functions which need to be upgraded at some point
1258      for (Module::iterator FI = TheModule->begin(), FE = TheModule->end();
1259           FI != FE; ++FI) {
1260        Function* NewFn;
1261        if (UpgradeIntrinsicFunction(FI, NewFn))
1262          UpgradedIntrinsics.push_back(std::make_pair(FI, NewFn));
1263      }
1264
1265      // Force deallocation of memory for these vectors to favor the client that
1266      // want lazy deserialization.
1267      std::vector<std::pair<GlobalVariable*, unsigned> >().swap(GlobalInits);
1268      std::vector<std::pair<GlobalAlias*, unsigned> >().swap(AliasInits);
1269      std::vector<Function*>().swap(FunctionsWithBodies);
1270      return false;
1271    }
1272
1273    if (Code == bitc::ENTER_SUBBLOCK) {
1274      switch (Stream.ReadSubBlockID()) {
1275      default:  // Skip unknown content.
1276        if (Stream.SkipBlock())
1277          return Error("Malformed block record");
1278        break;
1279      case bitc::BLOCKINFO_BLOCK_ID:
1280        if (Stream.ReadBlockInfoBlock())
1281          return Error("Malformed BlockInfoBlock");
1282        break;
1283      case bitc::PARAMATTR_BLOCK_ID:
1284        if (ParseAttributeBlock())
1285          return true;
1286        break;
1287      case bitc::TYPE_BLOCK_ID:
1288        if (ParseTypeTable())
1289          return true;
1290        break;
1291      case bitc::TYPE_SYMTAB_BLOCK_ID:
1292        if (ParseTypeSymbolTable())
1293          return true;
1294        break;
1295      case bitc::VALUE_SYMTAB_BLOCK_ID:
1296        if (ParseValueSymbolTable())
1297          return true;
1298        break;
1299      case bitc::CONSTANTS_BLOCK_ID:
1300        if (ParseConstants() || ResolveGlobalAndAliasInits())
1301          return true;
1302        break;
1303      case bitc::METADATA_BLOCK_ID:
1304        if (ParseMetadata())
1305          return true;
1306        break;
1307      case bitc::FUNCTION_BLOCK_ID:
1308        // If this is the first function body we've seen, reverse the
1309        // FunctionsWithBodies list.
1310        if (!HasReversedFunctionsWithBodies) {
1311          std::reverse(FunctionsWithBodies.begin(), FunctionsWithBodies.end());
1312          HasReversedFunctionsWithBodies = true;
1313        }
1314
1315        if (RememberAndSkipFunctionBody())
1316          return true;
1317        break;
1318      }
1319      continue;
1320    }
1321
1322    if (Code == bitc::DEFINE_ABBREV) {
1323      Stream.ReadAbbrevRecord();
1324      continue;
1325    }
1326
1327    // Read a record.
1328    switch (Stream.ReadRecord(Code, Record)) {
1329    default: break;  // Default behavior, ignore unknown content.
1330    case bitc::MODULE_CODE_VERSION:  // VERSION: [version#]
1331      if (Record.size() < 1)
1332        return Error("Malformed MODULE_CODE_VERSION");
1333      // Only version #0 is supported so far.
1334      if (Record[0] != 0)
1335        return Error("Unknown bitstream version!");
1336      break;
1337    case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
1338      std::string S;
1339      if (ConvertToString(Record, 0, S))
1340        return Error("Invalid MODULE_CODE_TRIPLE record");
1341      TheModule->setTargetTriple(S);
1342      break;
1343    }
1344    case bitc::MODULE_CODE_DATALAYOUT: {  // DATALAYOUT: [strchr x N]
1345      std::string S;
1346      if (ConvertToString(Record, 0, S))
1347        return Error("Invalid MODULE_CODE_DATALAYOUT record");
1348      TheModule->setDataLayout(S);
1349      break;
1350    }
1351    case bitc::MODULE_CODE_ASM: {  // ASM: [strchr x N]
1352      std::string S;
1353      if (ConvertToString(Record, 0, S))
1354        return Error("Invalid MODULE_CODE_ASM record");
1355      TheModule->setModuleInlineAsm(S);
1356      break;
1357    }
1358    case bitc::MODULE_CODE_DEPLIB: {  // DEPLIB: [strchr x N]
1359      std::string S;
1360      if (ConvertToString(Record, 0, S))
1361        return Error("Invalid MODULE_CODE_DEPLIB record");
1362      TheModule->addLibrary(S);
1363      break;
1364    }
1365    case bitc::MODULE_CODE_SECTIONNAME: {  // SECTIONNAME: [strchr x N]
1366      std::string S;
1367      if (ConvertToString(Record, 0, S))
1368        return Error("Invalid MODULE_CODE_SECTIONNAME record");
1369      SectionTable.push_back(S);
1370      break;
1371    }
1372    case bitc::MODULE_CODE_GCNAME: {  // SECTIONNAME: [strchr x N]
1373      std::string S;
1374      if (ConvertToString(Record, 0, S))
1375        return Error("Invalid MODULE_CODE_GCNAME record");
1376      GCTable.push_back(S);
1377      break;
1378    }
1379    // GLOBALVAR: [pointer type, isconst, initid,
1380    //             linkage, alignment, section, visibility, threadlocal]
1381    case bitc::MODULE_CODE_GLOBALVAR: {
1382      if (Record.size() < 6)
1383        return Error("Invalid MODULE_CODE_GLOBALVAR record");
1384      const Type *Ty = getTypeByID(Record[0]);
1385      if (!isa<PointerType>(Ty))
1386        return Error("Global not a pointer type!");
1387      unsigned AddressSpace = cast<PointerType>(Ty)->getAddressSpace();
1388      Ty = cast<PointerType>(Ty)->getElementType();
1389
1390      bool isConstant = Record[1];
1391      GlobalValue::LinkageTypes Linkage = GetDecodedLinkage(Record[3]);
1392      unsigned Alignment = (1 << Record[4]) >> 1;
1393      std::string Section;
1394      if (Record[5]) {
1395        if (Record[5]-1 >= SectionTable.size())
1396          return Error("Invalid section ID");
1397        Section = SectionTable[Record[5]-1];
1398      }
1399      GlobalValue::VisibilityTypes Visibility = GlobalValue::DefaultVisibility;
1400      if (Record.size() > 6)
1401        Visibility = GetDecodedVisibility(Record[6]);
1402      bool isThreadLocal = false;
1403      if (Record.size() > 7)
1404        isThreadLocal = Record[7];
1405
1406      GlobalVariable *NewGV =
1407        new GlobalVariable(*TheModule, Ty, isConstant, Linkage, 0, "", 0,
1408                           isThreadLocal, AddressSpace);
1409      NewGV->setAlignment(Alignment);
1410      if (!Section.empty())
1411        NewGV->setSection(Section);
1412      NewGV->setVisibility(Visibility);
1413      NewGV->setThreadLocal(isThreadLocal);
1414
1415      ValueList.push_back(NewGV);
1416
1417      // Remember which value to use for the global initializer.
1418      if (unsigned InitID = Record[2])
1419        GlobalInits.push_back(std::make_pair(NewGV, InitID-1));
1420      break;
1421    }
1422    // FUNCTION:  [type, callingconv, isproto, linkage, paramattr,
1423    //             alignment, section, visibility, gc]
1424    case bitc::MODULE_CODE_FUNCTION: {
1425      if (Record.size() < 8)
1426        return Error("Invalid MODULE_CODE_FUNCTION record");
1427      const Type *Ty = getTypeByID(Record[0]);
1428      if (!isa<PointerType>(Ty))
1429        return Error("Function not a pointer type!");
1430      const FunctionType *FTy =
1431        dyn_cast<FunctionType>(cast<PointerType>(Ty)->getElementType());
1432      if (!FTy)
1433        return Error("Function not a pointer to function type!");
1434
1435      Function *Func = Function::Create(FTy, GlobalValue::ExternalLinkage,
1436                                        "", TheModule);
1437
1438      Func->setCallingConv(static_cast<CallingConv::ID>(Record[1]));
1439      bool isProto = Record[2];
1440      Func->setLinkage(GetDecodedLinkage(Record[3]));
1441      Func->setAttributes(getAttributes(Record[4]));
1442
1443      Func->setAlignment((1 << Record[5]) >> 1);
1444      if (Record[6]) {
1445        if (Record[6]-1 >= SectionTable.size())
1446          return Error("Invalid section ID");
1447        Func->setSection(SectionTable[Record[6]-1]);
1448      }
1449      Func->setVisibility(GetDecodedVisibility(Record[7]));
1450      if (Record.size() > 8 && Record[8]) {
1451        if (Record[8]-1 > GCTable.size())
1452          return Error("Invalid GC ID");
1453        Func->setGC(GCTable[Record[8]-1].c_str());
1454      }
1455      ValueList.push_back(Func);
1456
1457      // If this is a function with a body, remember the prototype we are
1458      // creating now, so that we can match up the body with them later.
1459      if (!isProto)
1460        FunctionsWithBodies.push_back(Func);
1461      break;
1462    }
1463    // ALIAS: [alias type, aliasee val#, linkage]
1464    // ALIAS: [alias type, aliasee val#, linkage, visibility]
1465    case bitc::MODULE_CODE_ALIAS: {
1466      if (Record.size() < 3)
1467        return Error("Invalid MODULE_ALIAS record");
1468      const Type *Ty = getTypeByID(Record[0]);
1469      if (!isa<PointerType>(Ty))
1470        return Error("Function not a pointer type!");
1471
1472      GlobalAlias *NewGA = new GlobalAlias(Ty, GetDecodedLinkage(Record[2]),
1473                                           "", 0, TheModule);
1474      // Old bitcode files didn't have visibility field.
1475      if (Record.size() > 3)
1476        NewGA->setVisibility(GetDecodedVisibility(Record[3]));
1477      ValueList.push_back(NewGA);
1478      AliasInits.push_back(std::make_pair(NewGA, Record[1]));
1479      break;
1480    }
1481    /// MODULE_CODE_PURGEVALS: [numvals]
1482    case bitc::MODULE_CODE_PURGEVALS:
1483      // Trim down the value list to the specified size.
1484      if (Record.size() < 1 || Record[0] > ValueList.size())
1485        return Error("Invalid MODULE_PURGEVALS record");
1486      ValueList.shrinkTo(Record[0]);
1487      break;
1488    }
1489    Record.clear();
1490  }
1491
1492  return Error("Premature end of bitstream");
1493}
1494
1495bool BitcodeReader::ParseBitcode() {
1496  TheModule = 0;
1497
1498  if (Buffer->getBufferSize() & 3)
1499    return Error("Bitcode stream should be a multiple of 4 bytes in length");
1500
1501  unsigned char *BufPtr = (unsigned char *)Buffer->getBufferStart();
1502  unsigned char *BufEnd = BufPtr+Buffer->getBufferSize();
1503
1504  // If we have a wrapper header, parse it and ignore the non-bc file contents.
1505  // The magic number is 0x0B17C0DE stored in little endian.
1506  if (isBitcodeWrapper(BufPtr, BufEnd))
1507    if (SkipBitcodeWrapperHeader(BufPtr, BufEnd))
1508      return Error("Invalid bitcode wrapper header");
1509
1510  StreamFile.init(BufPtr, BufEnd);
1511  Stream.init(StreamFile);
1512
1513  // Sniff for the signature.
1514  if (Stream.Read(8) != 'B' ||
1515      Stream.Read(8) != 'C' ||
1516      Stream.Read(4) != 0x0 ||
1517      Stream.Read(4) != 0xC ||
1518      Stream.Read(4) != 0xE ||
1519      Stream.Read(4) != 0xD)
1520    return Error("Invalid bitcode signature");
1521
1522  // We expect a number of well-defined blocks, though we don't necessarily
1523  // need to understand them all.
1524  while (!Stream.AtEndOfStream()) {
1525    unsigned Code = Stream.ReadCode();
1526
1527    if (Code != bitc::ENTER_SUBBLOCK)
1528      return Error("Invalid record at top-level");
1529
1530    unsigned BlockID = Stream.ReadSubBlockID();
1531
1532    // We only know the MODULE subblock ID.
1533    switch (BlockID) {
1534    case bitc::BLOCKINFO_BLOCK_ID:
1535      if (Stream.ReadBlockInfoBlock())
1536        return Error("Malformed BlockInfoBlock");
1537      break;
1538    case bitc::MODULE_BLOCK_ID:
1539      if (ParseModule(Buffer->getBufferIdentifier()))
1540        return true;
1541      break;
1542    default:
1543      if (Stream.SkipBlock())
1544        return Error("Malformed block record");
1545      break;
1546    }
1547  }
1548
1549  return false;
1550}
1551
1552/// ParseMetadataAttachment - Parse metadata attachments.
1553bool BitcodeReader::ParseMetadataAttachment() {
1554  if (Stream.EnterSubBlock(bitc::METADATA_ATTACHMENT_ID))
1555    return Error("Malformed block record");
1556
1557  MetadataContext &TheMetadata = Context.getMetadata();
1558  SmallVector<uint64_t, 64> Record;
1559  while(1) {
1560    unsigned Code = Stream.ReadCode();
1561    if (Code == bitc::END_BLOCK) {
1562      if (Stream.ReadBlockEnd())
1563        return Error("Error at end of PARAMATTR block");
1564      break;
1565    }
1566    if (Code == bitc::DEFINE_ABBREV) {
1567      Stream.ReadAbbrevRecord();
1568      continue;
1569    }
1570    // Read a metadata attachment record.
1571    Record.clear();
1572    switch (Stream.ReadRecord(Code, Record)) {
1573    default:  // Default behavior: ignore.
1574      break;
1575    case bitc::METADATA_ATTACHMENT: {
1576      unsigned RecordLength = Record.size();
1577      if (Record.empty() || (RecordLength - 1) % 2 == 1)
1578        return Error ("Invalid METADATA_ATTACHMENT reader!");
1579      Instruction *Inst = InstructionList[Record[0]];
1580      for (unsigned i = 1; i != RecordLength; i = i+2) {
1581        unsigned Kind = Record[i];
1582        Value *Node = MDValueList.getValueFwdRef(Record[i+1]);
1583        TheMetadata.addMD(Kind, cast<MDNode>(Node), Inst);
1584      }
1585      break;
1586    }
1587    }
1588  }
1589  return false;
1590}
1591
1592/// ParseFunctionBody - Lazily parse the specified function body block.
1593bool BitcodeReader::ParseFunctionBody(Function *F) {
1594  if (Stream.EnterSubBlock(bitc::FUNCTION_BLOCK_ID))
1595    return Error("Malformed block record");
1596
1597  unsigned ModuleValueListSize = ValueList.size();
1598
1599  // Add all the function arguments to the value table.
1600  for(Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
1601    ValueList.push_back(I);
1602
1603  unsigned NextValueNo = ValueList.size();
1604  BasicBlock *CurBB = 0;
1605  unsigned CurBBNo = 0;
1606
1607  // Read all the records.
1608  SmallVector<uint64_t, 64> Record;
1609  while (1) {
1610    unsigned Code = Stream.ReadCode();
1611    if (Code == bitc::END_BLOCK) {
1612      if (Stream.ReadBlockEnd())
1613        return Error("Error at end of function block");
1614      break;
1615    }
1616
1617    if (Code == bitc::ENTER_SUBBLOCK) {
1618      switch (Stream.ReadSubBlockID()) {
1619      default:  // Skip unknown content.
1620        if (Stream.SkipBlock())
1621          return Error("Malformed block record");
1622        break;
1623      case bitc::CONSTANTS_BLOCK_ID:
1624        if (ParseConstants()) return true;
1625        NextValueNo = ValueList.size();
1626        break;
1627      case bitc::VALUE_SYMTAB_BLOCK_ID:
1628        if (ParseValueSymbolTable()) return true;
1629        break;
1630      case bitc::METADATA_ATTACHMENT_ID:
1631        if (ParseMetadataAttachment()) return true;
1632        break;
1633      }
1634      continue;
1635    }
1636
1637    if (Code == bitc::DEFINE_ABBREV) {
1638      Stream.ReadAbbrevRecord();
1639      continue;
1640    }
1641
1642    // Read a record.
1643    Record.clear();
1644    Instruction *I = 0;
1645    unsigned BitCode = Stream.ReadRecord(Code, Record);
1646    switch (BitCode) {
1647    default: // Default behavior: reject
1648      return Error("Unknown instruction");
1649    case bitc::FUNC_CODE_DECLAREBLOCKS:     // DECLAREBLOCKS: [nblocks]
1650      if (Record.size() < 1 || Record[0] == 0)
1651        return Error("Invalid DECLAREBLOCKS record");
1652      // Create all the basic blocks for the function.
1653      FunctionBBs.resize(Record[0]);
1654      for (unsigned i = 0, e = FunctionBBs.size(); i != e; ++i)
1655        FunctionBBs[i] = BasicBlock::Create(Context, "", F);
1656      CurBB = FunctionBBs[0];
1657      continue;
1658
1659    case bitc::FUNC_CODE_INST_BINOP: {    // BINOP: [opval, ty, opval, opcode]
1660      unsigned OpNum = 0;
1661      Value *LHS, *RHS;
1662      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
1663          getValue(Record, OpNum, LHS->getType(), RHS) ||
1664          OpNum+1 > Record.size())
1665        return Error("Invalid BINOP record");
1666
1667      int Opc = GetDecodedBinaryOpcode(Record[OpNum++], LHS->getType());
1668      if (Opc == -1) return Error("Invalid BINOP record");
1669      I = BinaryOperator::Create((Instruction::BinaryOps)Opc, LHS, RHS);
1670      InstructionList.push_back(I);
1671      if (OpNum < Record.size()) {
1672        if (Opc == Instruction::Add ||
1673            Opc == Instruction::Sub ||
1674            Opc == Instruction::Mul) {
1675          if (Record[3] & (1 << bitc::OBO_NO_SIGNED_WRAP))
1676            cast<BinaryOperator>(I)->setHasNoSignedWrap(true);
1677          if (Record[3] & (1 << bitc::OBO_NO_UNSIGNED_WRAP))
1678            cast<BinaryOperator>(I)->setHasNoUnsignedWrap(true);
1679        } else if (Opc == Instruction::SDiv) {
1680          if (Record[3] & (1 << bitc::SDIV_EXACT))
1681            cast<BinaryOperator>(I)->setIsExact(true);
1682        }
1683      }
1684      break;
1685    }
1686    case bitc::FUNC_CODE_INST_CAST: {    // CAST: [opval, opty, destty, castopc]
1687      unsigned OpNum = 0;
1688      Value *Op;
1689      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
1690          OpNum+2 != Record.size())
1691        return Error("Invalid CAST record");
1692
1693      const Type *ResTy = getTypeByID(Record[OpNum]);
1694      int Opc = GetDecodedCastOpcode(Record[OpNum+1]);
1695      if (Opc == -1 || ResTy == 0)
1696        return Error("Invalid CAST record");
1697      I = CastInst::Create((Instruction::CastOps)Opc, Op, ResTy);
1698      InstructionList.push_back(I);
1699      break;
1700    }
1701    case bitc::FUNC_CODE_INST_INBOUNDS_GEP:
1702    case bitc::FUNC_CODE_INST_GEP: { // GEP: [n x operands]
1703      unsigned OpNum = 0;
1704      Value *BasePtr;
1705      if (getValueTypePair(Record, OpNum, NextValueNo, BasePtr))
1706        return Error("Invalid GEP record");
1707
1708      SmallVector<Value*, 16> GEPIdx;
1709      while (OpNum != Record.size()) {
1710        Value *Op;
1711        if (getValueTypePair(Record, OpNum, NextValueNo, Op))
1712          return Error("Invalid GEP record");
1713        GEPIdx.push_back(Op);
1714      }
1715
1716      I = GetElementPtrInst::Create(BasePtr, GEPIdx.begin(), GEPIdx.end());
1717      InstructionList.push_back(I);
1718      if (BitCode == bitc::FUNC_CODE_INST_INBOUNDS_GEP)
1719        cast<GetElementPtrInst>(I)->setIsInBounds(true);
1720      break;
1721    }
1722
1723    case bitc::FUNC_CODE_INST_EXTRACTVAL: {
1724                                       // EXTRACTVAL: [opty, opval, n x indices]
1725      unsigned OpNum = 0;
1726      Value *Agg;
1727      if (getValueTypePair(Record, OpNum, NextValueNo, Agg))
1728        return Error("Invalid EXTRACTVAL record");
1729
1730      SmallVector<unsigned, 4> EXTRACTVALIdx;
1731      for (unsigned RecSize = Record.size();
1732           OpNum != RecSize; ++OpNum) {
1733        uint64_t Index = Record[OpNum];
1734        if ((unsigned)Index != Index)
1735          return Error("Invalid EXTRACTVAL index");
1736        EXTRACTVALIdx.push_back((unsigned)Index);
1737      }
1738
1739      I = ExtractValueInst::Create(Agg,
1740                                   EXTRACTVALIdx.begin(), EXTRACTVALIdx.end());
1741      InstructionList.push_back(I);
1742      break;
1743    }
1744
1745    case bitc::FUNC_CODE_INST_INSERTVAL: {
1746                           // INSERTVAL: [opty, opval, opty, opval, n x indices]
1747      unsigned OpNum = 0;
1748      Value *Agg;
1749      if (getValueTypePair(Record, OpNum, NextValueNo, Agg))
1750        return Error("Invalid INSERTVAL record");
1751      Value *Val;
1752      if (getValueTypePair(Record, OpNum, NextValueNo, Val))
1753        return Error("Invalid INSERTVAL record");
1754
1755      SmallVector<unsigned, 4> INSERTVALIdx;
1756      for (unsigned RecSize = Record.size();
1757           OpNum != RecSize; ++OpNum) {
1758        uint64_t Index = Record[OpNum];
1759        if ((unsigned)Index != Index)
1760          return Error("Invalid INSERTVAL index");
1761        INSERTVALIdx.push_back((unsigned)Index);
1762      }
1763
1764      I = InsertValueInst::Create(Agg, Val,
1765                                  INSERTVALIdx.begin(), INSERTVALIdx.end());
1766      InstructionList.push_back(I);
1767      break;
1768    }
1769
1770    case bitc::FUNC_CODE_INST_SELECT: { // SELECT: [opval, ty, opval, opval]
1771      // obsolete form of select
1772      // handles select i1 ... in old bitcode
1773      unsigned OpNum = 0;
1774      Value *TrueVal, *FalseVal, *Cond;
1775      if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
1776          getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
1777          getValue(Record, OpNum, Type::getInt1Ty(Context), Cond))
1778        return Error("Invalid SELECT record");
1779
1780      I = SelectInst::Create(Cond, TrueVal, FalseVal);
1781      InstructionList.push_back(I);
1782      break;
1783    }
1784
1785    case bitc::FUNC_CODE_INST_VSELECT: {// VSELECT: [ty,opval,opval,predty,pred]
1786      // new form of select
1787      // handles select i1 or select [N x i1]
1788      unsigned OpNum = 0;
1789      Value *TrueVal, *FalseVal, *Cond;
1790      if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
1791          getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
1792          getValueTypePair(Record, OpNum, NextValueNo, Cond))
1793        return Error("Invalid SELECT record");
1794
1795      // select condition can be either i1 or [N x i1]
1796      if (const VectorType* vector_type =
1797          dyn_cast<const VectorType>(Cond->getType())) {
1798        // expect <n x i1>
1799        if (vector_type->getElementType() != Type::getInt1Ty(Context))
1800          return Error("Invalid SELECT condition type");
1801      } else {
1802        // expect i1
1803        if (Cond->getType() != Type::getInt1Ty(Context))
1804          return Error("Invalid SELECT condition type");
1805      }
1806
1807      I = SelectInst::Create(Cond, TrueVal, FalseVal);
1808      InstructionList.push_back(I);
1809      break;
1810    }
1811
1812    case bitc::FUNC_CODE_INST_EXTRACTELT: { // EXTRACTELT: [opty, opval, opval]
1813      unsigned OpNum = 0;
1814      Value *Vec, *Idx;
1815      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
1816          getValue(Record, OpNum, Type::getInt32Ty(Context), Idx))
1817        return Error("Invalid EXTRACTELT record");
1818      I = ExtractElementInst::Create(Vec, Idx);
1819      InstructionList.push_back(I);
1820      break;
1821    }
1822
1823    case bitc::FUNC_CODE_INST_INSERTELT: { // INSERTELT: [ty, opval,opval,opval]
1824      unsigned OpNum = 0;
1825      Value *Vec, *Elt, *Idx;
1826      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
1827          getValue(Record, OpNum,
1828                   cast<VectorType>(Vec->getType())->getElementType(), Elt) ||
1829          getValue(Record, OpNum, Type::getInt32Ty(Context), Idx))
1830        return Error("Invalid INSERTELT record");
1831      I = InsertElementInst::Create(Vec, Elt, Idx);
1832      InstructionList.push_back(I);
1833      break;
1834    }
1835
1836    case bitc::FUNC_CODE_INST_SHUFFLEVEC: {// SHUFFLEVEC: [opval,ty,opval,opval]
1837      unsigned OpNum = 0;
1838      Value *Vec1, *Vec2, *Mask;
1839      if (getValueTypePair(Record, OpNum, NextValueNo, Vec1) ||
1840          getValue(Record, OpNum, Vec1->getType(), Vec2))
1841        return Error("Invalid SHUFFLEVEC record");
1842
1843      if (getValueTypePair(Record, OpNum, NextValueNo, Mask))
1844        return Error("Invalid SHUFFLEVEC record");
1845      I = new ShuffleVectorInst(Vec1, Vec2, Mask);
1846      InstructionList.push_back(I);
1847      break;
1848    }
1849
1850    case bitc::FUNC_CODE_INST_CMP:   // CMP: [opty, opval, opval, pred]
1851      // Old form of ICmp/FCmp returning bool
1852      // Existed to differentiate between icmp/fcmp and vicmp/vfcmp which were
1853      // both legal on vectors but had different behaviour.
1854    case bitc::FUNC_CODE_INST_CMP2: { // CMP2: [opty, opval, opval, pred]
1855      // FCmp/ICmp returning bool or vector of bool
1856
1857      unsigned OpNum = 0;
1858      Value *LHS, *RHS;
1859      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
1860          getValue(Record, OpNum, LHS->getType(), RHS) ||
1861          OpNum+1 != Record.size())
1862        return Error("Invalid CMP record");
1863
1864      if (LHS->getType()->isFPOrFPVector())
1865        I = new FCmpInst((FCmpInst::Predicate)Record[OpNum], LHS, RHS);
1866      else
1867        I = new ICmpInst((ICmpInst::Predicate)Record[OpNum], LHS, RHS);
1868      InstructionList.push_back(I);
1869      break;
1870    }
1871
1872    case bitc::FUNC_CODE_INST_GETRESULT: { // GETRESULT: [ty, val, n]
1873      if (Record.size() != 2)
1874        return Error("Invalid GETRESULT record");
1875      unsigned OpNum = 0;
1876      Value *Op;
1877      getValueTypePair(Record, OpNum, NextValueNo, Op);
1878      unsigned Index = Record[1];
1879      I = ExtractValueInst::Create(Op, Index);
1880      InstructionList.push_back(I);
1881      break;
1882    }
1883
1884    case bitc::FUNC_CODE_INST_RET: // RET: [opty,opval<optional>]
1885      {
1886        unsigned Size = Record.size();
1887        if (Size == 0) {
1888          I = ReturnInst::Create(Context);
1889          InstructionList.push_back(I);
1890          break;
1891        }
1892
1893        unsigned OpNum = 0;
1894        SmallVector<Value *,4> Vs;
1895        do {
1896          Value *Op = NULL;
1897          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
1898            return Error("Invalid RET record");
1899          Vs.push_back(Op);
1900        } while(OpNum != Record.size());
1901
1902        const Type *ReturnType = F->getReturnType();
1903        if (Vs.size() > 1 ||
1904            (isa<StructType>(ReturnType) &&
1905             (Vs.empty() || Vs[0]->getType() != ReturnType))) {
1906          Value *RV = UndefValue::get(ReturnType);
1907          for (unsigned i = 0, e = Vs.size(); i != e; ++i) {
1908            I = InsertValueInst::Create(RV, Vs[i], i, "mrv");
1909            InstructionList.push_back(I);
1910            CurBB->getInstList().push_back(I);
1911            ValueList.AssignValue(I, NextValueNo++);
1912            RV = I;
1913          }
1914          I = ReturnInst::Create(Context, RV);
1915          InstructionList.push_back(I);
1916          break;
1917        }
1918
1919        I = ReturnInst::Create(Context, Vs[0]);
1920        InstructionList.push_back(I);
1921        break;
1922      }
1923    case bitc::FUNC_CODE_INST_BR: { // BR: [bb#, bb#, opval] or [bb#]
1924      if (Record.size() != 1 && Record.size() != 3)
1925        return Error("Invalid BR record");
1926      BasicBlock *TrueDest = getBasicBlock(Record[0]);
1927      if (TrueDest == 0)
1928        return Error("Invalid BR record");
1929
1930      if (Record.size() == 1) {
1931        I = BranchInst::Create(TrueDest);
1932        InstructionList.push_back(I);
1933      }
1934      else {
1935        BasicBlock *FalseDest = getBasicBlock(Record[1]);
1936        Value *Cond = getFnValueByID(Record[2], Type::getInt1Ty(Context));
1937        if (FalseDest == 0 || Cond == 0)
1938          return Error("Invalid BR record");
1939        I = BranchInst::Create(TrueDest, FalseDest, Cond);
1940        InstructionList.push_back(I);
1941      }
1942      break;
1943    }
1944    case bitc::FUNC_CODE_INST_SWITCH: { // SWITCH: [opty, opval, n, n x ops]
1945      if (Record.size() < 3 || (Record.size() & 1) == 0)
1946        return Error("Invalid SWITCH record");
1947      const Type *OpTy = getTypeByID(Record[0]);
1948      Value *Cond = getFnValueByID(Record[1], OpTy);
1949      BasicBlock *Default = getBasicBlock(Record[2]);
1950      if (OpTy == 0 || Cond == 0 || Default == 0)
1951        return Error("Invalid SWITCH record");
1952      unsigned NumCases = (Record.size()-3)/2;
1953      SwitchInst *SI = SwitchInst::Create(Cond, Default, NumCases);
1954      InstructionList.push_back(SI);
1955      for (unsigned i = 0, e = NumCases; i != e; ++i) {
1956        ConstantInt *CaseVal =
1957          dyn_cast_or_null<ConstantInt>(getFnValueByID(Record[3+i*2], OpTy));
1958        BasicBlock *DestBB = getBasicBlock(Record[1+3+i*2]);
1959        if (CaseVal == 0 || DestBB == 0) {
1960          delete SI;
1961          return Error("Invalid SWITCH record!");
1962        }
1963        SI->addCase(CaseVal, DestBB);
1964      }
1965      I = SI;
1966      break;
1967    }
1968
1969    case bitc::FUNC_CODE_INST_INVOKE: {
1970      // INVOKE: [attrs, cc, normBB, unwindBB, fnty, op0,op1,op2, ...]
1971      if (Record.size() < 4) return Error("Invalid INVOKE record");
1972      AttrListPtr PAL = getAttributes(Record[0]);
1973      unsigned CCInfo = Record[1];
1974      BasicBlock *NormalBB = getBasicBlock(Record[2]);
1975      BasicBlock *UnwindBB = getBasicBlock(Record[3]);
1976
1977      unsigned OpNum = 4;
1978      Value *Callee;
1979      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
1980        return Error("Invalid INVOKE record");
1981
1982      const PointerType *CalleeTy = dyn_cast<PointerType>(Callee->getType());
1983      const FunctionType *FTy = !CalleeTy ? 0 :
1984        dyn_cast<FunctionType>(CalleeTy->getElementType());
1985
1986      // Check that the right number of fixed parameters are here.
1987      if (FTy == 0 || NormalBB == 0 || UnwindBB == 0 ||
1988          Record.size() < OpNum+FTy->getNumParams())
1989        return Error("Invalid INVOKE record");
1990
1991      SmallVector<Value*, 16> Ops;
1992      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
1993        Ops.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
1994        if (Ops.back() == 0) return Error("Invalid INVOKE record");
1995      }
1996
1997      if (!FTy->isVarArg()) {
1998        if (Record.size() != OpNum)
1999          return Error("Invalid INVOKE record");
2000      } else {
2001        // Read type/value pairs for varargs params.
2002        while (OpNum != Record.size()) {
2003          Value *Op;
2004          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2005            return Error("Invalid INVOKE record");
2006          Ops.push_back(Op);
2007        }
2008      }
2009
2010      I = InvokeInst::Create(Callee, NormalBB, UnwindBB,
2011                             Ops.begin(), Ops.end());
2012      InstructionList.push_back(I);
2013      cast<InvokeInst>(I)->setCallingConv(
2014        static_cast<CallingConv::ID>(CCInfo));
2015      cast<InvokeInst>(I)->setAttributes(PAL);
2016      break;
2017    }
2018    case bitc::FUNC_CODE_INST_UNWIND: // UNWIND
2019      I = new UnwindInst(Context);
2020      InstructionList.push_back(I);
2021      break;
2022    case bitc::FUNC_CODE_INST_UNREACHABLE: // UNREACHABLE
2023      I = new UnreachableInst(Context);
2024      InstructionList.push_back(I);
2025      break;
2026    case bitc::FUNC_CODE_INST_PHI: { // PHI: [ty, val0,bb0, ...]
2027      if (Record.size() < 1 || ((Record.size()-1)&1))
2028        return Error("Invalid PHI record");
2029      const Type *Ty = getTypeByID(Record[0]);
2030      if (!Ty) return Error("Invalid PHI record");
2031
2032      PHINode *PN = PHINode::Create(Ty);
2033      InstructionList.push_back(PN);
2034      PN->reserveOperandSpace((Record.size()-1)/2);
2035
2036      for (unsigned i = 0, e = Record.size()-1; i != e; i += 2) {
2037        Value *V = getFnValueByID(Record[1+i], Ty);
2038        BasicBlock *BB = getBasicBlock(Record[2+i]);
2039        if (!V || !BB) return Error("Invalid PHI record");
2040        PN->addIncoming(V, BB);
2041      }
2042      I = PN;
2043      break;
2044    }
2045
2046    case bitc::FUNC_CODE_INST_MALLOC: { // MALLOC: [instty, op, align]
2047      // Autoupgrade malloc instruction to malloc call.
2048      // FIXME: Remove in LLVM 3.0.
2049      if (Record.size() < 3)
2050        return Error("Invalid MALLOC record");
2051      const PointerType *Ty =
2052        dyn_cast_or_null<PointerType>(getTypeByID(Record[0]));
2053      Value *Size = getFnValueByID(Record[1], Type::getInt32Ty(Context));
2054      if (!Ty || !Size) return Error("Invalid MALLOC record");
2055      if (!CurBB) return Error("Invalid malloc instruction with no BB");
2056      const Type *Int32Ty = IntegerType::getInt32Ty(CurBB->getContext());
2057      I = CallInst::CreateMalloc(CurBB, Int32Ty, Ty->getElementType(),
2058                                 Size, NULL);
2059      InstructionList.push_back(I);
2060      break;
2061    }
2062    case bitc::FUNC_CODE_INST_FREE: { // FREE: [op, opty]
2063      unsigned OpNum = 0;
2064      Value *Op;
2065      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
2066          OpNum != Record.size())
2067        return Error("Invalid FREE record");
2068      I = new FreeInst(Op);
2069      InstructionList.push_back(I);
2070      break;
2071    }
2072    case bitc::FUNC_CODE_INST_ALLOCA: { // ALLOCA: [instty, op, align]
2073      if (Record.size() < 3)
2074        return Error("Invalid ALLOCA record");
2075      const PointerType *Ty =
2076        dyn_cast_or_null<PointerType>(getTypeByID(Record[0]));
2077      Value *Size = getFnValueByID(Record[1], Type::getInt32Ty(Context));
2078      unsigned Align = Record[2];
2079      if (!Ty || !Size) return Error("Invalid ALLOCA record");
2080      I = new AllocaInst(Ty->getElementType(), Size, (1 << Align) >> 1);
2081      InstructionList.push_back(I);
2082      break;
2083    }
2084    case bitc::FUNC_CODE_INST_LOAD: { // LOAD: [opty, op, align, vol]
2085      unsigned OpNum = 0;
2086      Value *Op;
2087      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
2088          OpNum+2 != Record.size())
2089        return Error("Invalid LOAD record");
2090
2091      I = new LoadInst(Op, "", Record[OpNum+1], (1 << Record[OpNum]) >> 1);
2092      InstructionList.push_back(I);
2093      break;
2094    }
2095    case bitc::FUNC_CODE_INST_STORE2: { // STORE2:[ptrty, ptr, val, align, vol]
2096      unsigned OpNum = 0;
2097      Value *Val, *Ptr;
2098      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
2099          getValue(Record, OpNum,
2100                    cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
2101          OpNum+2 != Record.size())
2102        return Error("Invalid STORE record");
2103
2104      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1);
2105      InstructionList.push_back(I);
2106      break;
2107    }
2108    case bitc::FUNC_CODE_INST_STORE: { // STORE:[val, valty, ptr, align, vol]
2109      // FIXME: Legacy form of store instruction. Should be removed in LLVM 3.0.
2110      unsigned OpNum = 0;
2111      Value *Val, *Ptr;
2112      if (getValueTypePair(Record, OpNum, NextValueNo, Val) ||
2113          getValue(Record, OpNum,
2114                   PointerType::getUnqual(Val->getType()), Ptr)||
2115          OpNum+2 != Record.size())
2116        return Error("Invalid STORE record");
2117
2118      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1);
2119      InstructionList.push_back(I);
2120      break;
2121    }
2122    case bitc::FUNC_CODE_INST_CALL: {
2123      // CALL: [paramattrs, cc, fnty, fnid, arg0, arg1...]
2124      if (Record.size() < 3)
2125        return Error("Invalid CALL record");
2126
2127      AttrListPtr PAL = getAttributes(Record[0]);
2128      unsigned CCInfo = Record[1];
2129
2130      unsigned OpNum = 2;
2131      Value *Callee;
2132      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
2133        return Error("Invalid CALL record");
2134
2135      const PointerType *OpTy = dyn_cast<PointerType>(Callee->getType());
2136      const FunctionType *FTy = 0;
2137      if (OpTy) FTy = dyn_cast<FunctionType>(OpTy->getElementType());
2138      if (!FTy || Record.size() < FTy->getNumParams()+OpNum)
2139        return Error("Invalid CALL record");
2140
2141      SmallVector<Value*, 16> Args;
2142      // Read the fixed params.
2143      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
2144        if (FTy->getParamType(i)->getTypeID()==Type::LabelTyID)
2145          Args.push_back(getBasicBlock(Record[OpNum]));
2146        else
2147          Args.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
2148        if (Args.back() == 0) return Error("Invalid CALL record");
2149      }
2150
2151      // Read type/value pairs for varargs params.
2152      if (!FTy->isVarArg()) {
2153        if (OpNum != Record.size())
2154          return Error("Invalid CALL record");
2155      } else {
2156        while (OpNum != Record.size()) {
2157          Value *Op;
2158          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2159            return Error("Invalid CALL record");
2160          Args.push_back(Op);
2161        }
2162      }
2163
2164      I = CallInst::Create(Callee, Args.begin(), Args.end());
2165      InstructionList.push_back(I);
2166      cast<CallInst>(I)->setCallingConv(
2167        static_cast<CallingConv::ID>(CCInfo>>1));
2168      cast<CallInst>(I)->setTailCall(CCInfo & 1);
2169      cast<CallInst>(I)->setAttributes(PAL);
2170      break;
2171    }
2172    case bitc::FUNC_CODE_INST_VAARG: { // VAARG: [valistty, valist, instty]
2173      if (Record.size() < 3)
2174        return Error("Invalid VAARG record");
2175      const Type *OpTy = getTypeByID(Record[0]);
2176      Value *Op = getFnValueByID(Record[1], OpTy);
2177      const Type *ResTy = getTypeByID(Record[2]);
2178      if (!OpTy || !Op || !ResTy)
2179        return Error("Invalid VAARG record");
2180      I = new VAArgInst(Op, ResTy);
2181      InstructionList.push_back(I);
2182      break;
2183    }
2184    }
2185
2186    // Add instruction to end of current BB.  If there is no current BB, reject
2187    // this file.
2188    if (CurBB == 0) {
2189      delete I;
2190      return Error("Invalid instruction with no BB");
2191    }
2192    CurBB->getInstList().push_back(I);
2193
2194    // If this was a terminator instruction, move to the next block.
2195    if (isa<TerminatorInst>(I)) {
2196      ++CurBBNo;
2197      CurBB = CurBBNo < FunctionBBs.size() ? FunctionBBs[CurBBNo] : 0;
2198    }
2199
2200    // Non-void values get registered in the value table for future use.
2201    if (I && I->getType() != Type::getVoidTy(Context))
2202      ValueList.AssignValue(I, NextValueNo++);
2203  }
2204
2205  // Check the function list for unresolved values.
2206  if (Argument *A = dyn_cast<Argument>(ValueList.back())) {
2207    if (A->getParent() == 0) {
2208      // We found at least one unresolved value.  Nuke them all to avoid leaks.
2209      for (unsigned i = ModuleValueListSize, e = ValueList.size(); i != e; ++i){
2210        if ((A = dyn_cast<Argument>(ValueList.back())) && A->getParent() == 0) {
2211          A->replaceAllUsesWith(UndefValue::get(A->getType()));
2212          delete A;
2213        }
2214      }
2215      return Error("Never resolved value found in function!");
2216    }
2217  }
2218
2219  // Trim the value list down to the size it was before we parsed this function.
2220  ValueList.shrinkTo(ModuleValueListSize);
2221  std::vector<BasicBlock*>().swap(FunctionBBs);
2222
2223  return false;
2224}
2225
2226//===----------------------------------------------------------------------===//
2227// ModuleProvider implementation
2228//===----------------------------------------------------------------------===//
2229
2230
2231bool BitcodeReader::materializeFunction(Function *F, std::string *ErrInfo) {
2232  // If it already is material, ignore the request.
2233  if (!F->hasNotBeenReadFromBitcode()) return false;
2234
2235  DenseMap<Function*, std::pair<uint64_t, unsigned> >::iterator DFII =
2236    DeferredFunctionInfo.find(F);
2237  assert(DFII != DeferredFunctionInfo.end() && "Deferred function not found!");
2238
2239  // Move the bit stream to the saved position of the deferred function body and
2240  // restore the real linkage type for the function.
2241  Stream.JumpToBit(DFII->second.first);
2242  F->setLinkage((GlobalValue::LinkageTypes)DFII->second.second);
2243
2244  if (ParseFunctionBody(F)) {
2245    if (ErrInfo) *ErrInfo = ErrorString;
2246    return true;
2247  }
2248
2249  // Upgrade any old intrinsic calls in the function.
2250  for (UpgradedIntrinsicMap::iterator I = UpgradedIntrinsics.begin(),
2251       E = UpgradedIntrinsics.end(); I != E; ++I) {
2252    if (I->first != I->second) {
2253      for (Value::use_iterator UI = I->first->use_begin(),
2254           UE = I->first->use_end(); UI != UE; ) {
2255        if (CallInst* CI = dyn_cast<CallInst>(*UI++))
2256          UpgradeIntrinsicCall(CI, I->second);
2257      }
2258    }
2259  }
2260
2261  return false;
2262}
2263
2264void BitcodeReader::dematerializeFunction(Function *F) {
2265  // If this function isn't materialized, or if it is a proto, this is a noop.
2266  if (F->hasNotBeenReadFromBitcode() || F->isDeclaration())
2267    return;
2268
2269  assert(DeferredFunctionInfo.count(F) && "No info to read function later?");
2270
2271  // Just forget the function body, we can remat it later.
2272  F->deleteBody();
2273  F->setLinkage(GlobalValue::GhostLinkage);
2274}
2275
2276
2277Module *BitcodeReader::materializeModule(std::string *ErrInfo) {
2278  // Iterate over the module, deserializing any functions that are still on
2279  // disk.
2280  for (Module::iterator F = TheModule->begin(), E = TheModule->end();
2281       F != E; ++F)
2282    if (F->hasNotBeenReadFromBitcode() &&
2283        materializeFunction(F, ErrInfo))
2284      return 0;
2285
2286  // Upgrade any intrinsic calls that slipped through (should not happen!) and
2287  // delete the old functions to clean up. We can't do this unless the entire
2288  // module is materialized because there could always be another function body
2289  // with calls to the old function.
2290  for (std::vector<std::pair<Function*, Function*> >::iterator I =
2291       UpgradedIntrinsics.begin(), E = UpgradedIntrinsics.end(); I != E; ++I) {
2292    if (I->first != I->second) {
2293      for (Value::use_iterator UI = I->first->use_begin(),
2294           UE = I->first->use_end(); UI != UE; ) {
2295        if (CallInst* CI = dyn_cast<CallInst>(*UI++))
2296          UpgradeIntrinsicCall(CI, I->second);
2297      }
2298      if (!I->first->use_empty())
2299        I->first->replaceAllUsesWith(I->second);
2300      I->first->eraseFromParent();
2301    }
2302  }
2303  std::vector<std::pair<Function*, Function*> >().swap(UpgradedIntrinsics);
2304
2305  // Check debug info intrinsics.
2306  CheckDebugInfoIntrinsics(TheModule);
2307
2308  return TheModule;
2309}
2310
2311
2312/// This method is provided by the parent ModuleProvde class and overriden
2313/// here. It simply releases the module from its provided and frees up our
2314/// state.
2315/// @brief Release our hold on the generated module
2316Module *BitcodeReader::releaseModule(std::string *ErrInfo) {
2317  // Since we're losing control of this Module, we must hand it back complete
2318  Module *M = ModuleProvider::releaseModule(ErrInfo);
2319  FreeState();
2320  return M;
2321}
2322
2323
2324//===----------------------------------------------------------------------===//
2325// External interface
2326//===----------------------------------------------------------------------===//
2327
2328/// getBitcodeModuleProvider - lazy function-at-a-time loading from a file.
2329///
2330ModuleProvider *llvm::getBitcodeModuleProvider(MemoryBuffer *Buffer,
2331                                               LLVMContext& Context,
2332                                               std::string *ErrMsg) {
2333  BitcodeReader *R = new BitcodeReader(Buffer, Context);
2334  if (R->ParseBitcode()) {
2335    if (ErrMsg)
2336      *ErrMsg = R->getErrorString();
2337
2338    // Don't let the BitcodeReader dtor delete 'Buffer'.
2339    R->releaseMemoryBuffer();
2340    delete R;
2341    return 0;
2342  }
2343  return R;
2344}
2345
2346/// ParseBitcodeFile - Read the specified bitcode file, returning the module.
2347/// If an error occurs, return null and fill in *ErrMsg if non-null.
2348Module *llvm::ParseBitcodeFile(MemoryBuffer *Buffer, LLVMContext& Context,
2349                               std::string *ErrMsg){
2350  BitcodeReader *R;
2351  R = static_cast<BitcodeReader*>(getBitcodeModuleProvider(Buffer, Context,
2352                                                           ErrMsg));
2353  if (!R) return 0;
2354
2355  // Read in the entire module.
2356  Module *M = R->materializeModule(ErrMsg);
2357
2358  // Don't let the BitcodeReader dtor delete 'Buffer', regardless of whether
2359  // there was an error.
2360  R->releaseMemoryBuffer();
2361
2362  // If there was no error, tell ModuleProvider not to delete it when its dtor
2363  // is run.
2364  if (M)
2365    M = R->releaseModule(ErrMsg);
2366
2367  delete R;
2368  return M;
2369}
2370