BitcodeReader.cpp revision 207855cff9b4811004b9720f28a5bd0adf3784b7
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/Module.h"
21#include "llvm/Operator.h"
22#include "llvm/AutoUpgrade.h"
23#include "llvm/ADT/SmallString.h"
24#include "llvm/ADT/SmallVector.h"
25#include "llvm/Support/MathExtras.h"
26#include "llvm/Support/MemoryBuffer.h"
27#include "llvm/OperandTraits.h"
28using namespace llvm;
29
30void BitcodeReader::FreeState() {
31  if (BufferOwned)
32    delete Buffer;
33  Buffer = 0;
34  std::vector<PATypeHolder>().swap(TypeList);
35  ValueList.clear();
36  MDValueList.clear();
37
38  std::vector<AttrListPtr>().swap(MAttributes);
39  std::vector<BasicBlock*>().swap(FunctionBBs);
40  std::vector<Function*>().swap(FunctionsWithBodies);
41  DeferredFunctionInfo.clear();
42}
43
44//===----------------------------------------------------------------------===//
45//  Helper functions to implement forward reference resolution, etc.
46//===----------------------------------------------------------------------===//
47
48/// ConvertToString - Convert a string from a record into an std::string, return
49/// true on failure.
50template<typename StrTy>
51static bool ConvertToString(SmallVector<uint64_t, 64> &Record, unsigned Idx,
52                            StrTy &Result) {
53  if (Idx > Record.size())
54    return true;
55
56  for (unsigned i = Idx, e = Record.size(); i != e; ++i)
57    Result += (char)Record[i];
58  return false;
59}
60
61static GlobalValue::LinkageTypes GetDecodedLinkage(unsigned Val) {
62  switch (Val) {
63  default: // Map unknown/new linkages to external
64  case 0:  return GlobalValue::ExternalLinkage;
65  case 1:  return GlobalValue::WeakAnyLinkage;
66  case 2:  return GlobalValue::AppendingLinkage;
67  case 3:  return GlobalValue::InternalLinkage;
68  case 4:  return GlobalValue::LinkOnceAnyLinkage;
69  case 5:  return GlobalValue::DLLImportLinkage;
70  case 6:  return GlobalValue::DLLExportLinkage;
71  case 7:  return GlobalValue::ExternalWeakLinkage;
72  case 8:  return GlobalValue::CommonLinkage;
73  case 9:  return GlobalValue::PrivateLinkage;
74  case 10: return GlobalValue::WeakODRLinkage;
75  case 11: return GlobalValue::LinkOnceODRLinkage;
76  case 12: return GlobalValue::AvailableExternallyLinkage;
77  case 13: return GlobalValue::LinkerPrivateLinkage;
78  case 14: return GlobalValue::LinkerWeakLinkage;
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->isFPOrFPVectorTy() ? Instruction::FAdd : Instruction::Add;
113  case bitc::BINOP_SUB:
114    return Ty->isFPOrFPVectorTy() ? Instruction::FSub : Instruction::Sub;
115  case bitc::BINOP_MUL:
116    return Ty->isFPOrFPVectorTy() ? Instruction::FMul : Instruction::Mul;
117  case bitc::BINOP_UDIV: return Instruction::UDiv;
118  case bitc::BINOP_SDIV:
119    return Ty->isFPOrFPVectorTy() ? Instruction::FDiv : Instruction::SDiv;
120  case bitc::BINOP_UREM: return Instruction::URem;
121  case bitc::BINOP_SREM:
122    return Ty->isFPOrFPVectorTy() ? 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 (ConstantUnion *UserCU = dyn_cast<ConstantUnion>(UserC)) {
298        NewC = ConstantUnion::get(UserCU->getType(), NewOps[0]);
299      } else if (isa<ConstantVector>(UserC)) {
300        NewC = ConstantVector::get(&NewOps[0], NewOps.size());
301      } else {
302        assert(isa<ConstantExpr>(UserC) && "Must be a ConstantExpr.");
303        NewC = cast<ConstantExpr>(UserC)->getWithOperands(&NewOps[0],
304                                                          NewOps.size());
305      }
306
307      UserC->replaceAllUsesWith(NewC);
308      UserC->destroyConstant();
309      NewOps.clear();
310    }
311
312    // Update all ValueHandles, they should be the only users at this point.
313    Placeholder->replaceAllUsesWith(RealVal);
314    delete Placeholder;
315  }
316}
317
318void BitcodeReaderMDValueList::AssignValue(Value *V, unsigned Idx) {
319  if (Idx == size()) {
320    push_back(V);
321    return;
322  }
323
324  if (Idx >= size())
325    resize(Idx+1);
326
327  WeakVH &OldV = MDValuePtrs[Idx];
328  if (OldV == 0) {
329    OldV = V;
330    return;
331  }
332
333  // If there was a forward reference to this value, replace it.
334  Value *PrevVal = OldV;
335  OldV->replaceAllUsesWith(V);
336  delete PrevVal;
337  // Deleting PrevVal sets Idx value in MDValuePtrs to null. Set new
338  // value for Idx.
339  MDValuePtrs[Idx] = V;
340}
341
342Value *BitcodeReaderMDValueList::getValueFwdRef(unsigned Idx) {
343  if (Idx >= size())
344    resize(Idx + 1);
345
346  if (Value *V = MDValuePtrs[Idx]) {
347    assert(V->getType()->isMetadataTy() && "Type mismatch in value table!");
348    return V;
349  }
350
351  // Create and return a placeholder, which will later be RAUW'd.
352  Value *V = new Argument(Type::getMetadataTy(Context));
353  MDValuePtrs[Idx] = V;
354  return V;
355}
356
357const Type *BitcodeReader::getTypeByID(unsigned ID, bool isTypeTable) {
358  // If the TypeID is in range, return it.
359  if (ID < TypeList.size())
360    return TypeList[ID].get();
361  if (!isTypeTable) return 0;
362
363  // The type table allows forward references.  Push as many Opaque types as
364  // needed to get up to ID.
365  while (TypeList.size() <= ID)
366    TypeList.push_back(OpaqueType::get(Context));
367  return TypeList.back().get();
368}
369
370//===----------------------------------------------------------------------===//
371//  Functions for parsing blocks from the bitcode file
372//===----------------------------------------------------------------------===//
373
374bool BitcodeReader::ParseAttributeBlock() {
375  if (Stream.EnterSubBlock(bitc::PARAMATTR_BLOCK_ID))
376    return Error("Malformed block record");
377
378  if (!MAttributes.empty())
379    return Error("Multiple PARAMATTR blocks found!");
380
381  SmallVector<uint64_t, 64> Record;
382
383  SmallVector<AttributeWithIndex, 8> Attrs;
384
385  // Read all the records.
386  while (1) {
387    unsigned Code = Stream.ReadCode();
388    if (Code == bitc::END_BLOCK) {
389      if (Stream.ReadBlockEnd())
390        return Error("Error at end of PARAMATTR block");
391      return false;
392    }
393
394    if (Code == bitc::ENTER_SUBBLOCK) {
395      // No known subblocks, always skip them.
396      Stream.ReadSubBlockID();
397      if (Stream.SkipBlock())
398        return Error("Malformed block record");
399      continue;
400    }
401
402    if (Code == bitc::DEFINE_ABBREV) {
403      Stream.ReadAbbrevRecord();
404      continue;
405    }
406
407    // Read a record.
408    Record.clear();
409    switch (Stream.ReadRecord(Code, Record)) {
410    default:  // Default behavior: ignore.
411      break;
412    case bitc::PARAMATTR_CODE_ENTRY: { // ENTRY: [paramidx0, attr0, ...]
413      if (Record.size() & 1)
414        return Error("Invalid ENTRY record");
415
416      // FIXME : Remove this autoupgrade code in LLVM 3.0.
417      // If Function attributes are using index 0 then transfer them
418      // to index ~0. Index 0 is used for return value attributes but used to be
419      // used for function attributes.
420      Attributes RetAttribute = Attribute::None;
421      Attributes FnAttribute = Attribute::None;
422      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
423        // FIXME: remove in LLVM 3.0
424        // The alignment is stored as a 16-bit raw value from bits 31--16.
425        // We shift the bits above 31 down by 11 bits.
426
427        unsigned Alignment = (Record[i+1] & (0xffffull << 16)) >> 16;
428        if (Alignment && !isPowerOf2_32(Alignment))
429          return Error("Alignment is not a power of two.");
430
431        Attributes ReconstitutedAttr = Record[i+1] & 0xffff;
432        if (Alignment)
433          ReconstitutedAttr |= Attribute::constructAlignmentFromInt(Alignment);
434        ReconstitutedAttr |= (Record[i+1] & (0xffffull << 32)) >> 11;
435        Record[i+1] = ReconstitutedAttr;
436
437        if (Record[i] == 0)
438          RetAttribute = Record[i+1];
439        else if (Record[i] == ~0U)
440          FnAttribute = Record[i+1];
441      }
442
443      unsigned OldRetAttrs = (Attribute::NoUnwind|Attribute::NoReturn|
444                              Attribute::ReadOnly|Attribute::ReadNone);
445
446      if (FnAttribute == Attribute::None && RetAttribute != Attribute::None &&
447          (RetAttribute & OldRetAttrs) != 0) {
448        if (FnAttribute == Attribute::None) { // add a slot so they get added.
449          Record.push_back(~0U);
450          Record.push_back(0);
451        }
452
453        FnAttribute  |= RetAttribute & OldRetAttrs;
454        RetAttribute &= ~OldRetAttrs;
455      }
456
457      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
458        if (Record[i] == 0) {
459          if (RetAttribute != Attribute::None)
460            Attrs.push_back(AttributeWithIndex::get(0, RetAttribute));
461        } else if (Record[i] == ~0U) {
462          if (FnAttribute != Attribute::None)
463            Attrs.push_back(AttributeWithIndex::get(~0U, FnAttribute));
464        } else if (Record[i+1] != Attribute::None)
465          Attrs.push_back(AttributeWithIndex::get(Record[i], Record[i+1]));
466      }
467
468      MAttributes.push_back(AttrListPtr::get(Attrs.begin(), Attrs.end()));
469      Attrs.clear();
470      break;
471    }
472    }
473  }
474}
475
476
477bool BitcodeReader::ParseTypeTable() {
478  if (Stream.EnterSubBlock(bitc::TYPE_BLOCK_ID))
479    return Error("Malformed block record");
480
481  if (!TypeList.empty())
482    return Error("Multiple TYPE_BLOCKs found!");
483
484  SmallVector<uint64_t, 64> Record;
485  unsigned NumRecords = 0;
486
487  // Read all the records for this type table.
488  while (1) {
489    unsigned Code = Stream.ReadCode();
490    if (Code == bitc::END_BLOCK) {
491      if (NumRecords != TypeList.size())
492        return Error("Invalid type forward reference in TYPE_BLOCK");
493      if (Stream.ReadBlockEnd())
494        return Error("Error at end of type table block");
495      return false;
496    }
497
498    if (Code == bitc::ENTER_SUBBLOCK) {
499      // No known subblocks, always skip them.
500      Stream.ReadSubBlockID();
501      if (Stream.SkipBlock())
502        return Error("Malformed block record");
503      continue;
504    }
505
506    if (Code == bitc::DEFINE_ABBREV) {
507      Stream.ReadAbbrevRecord();
508      continue;
509    }
510
511    // Read a record.
512    Record.clear();
513    const Type *ResultTy = 0;
514    switch (Stream.ReadRecord(Code, Record)) {
515    default:  // Default behavior: unknown type.
516      ResultTy = 0;
517      break;
518    case bitc::TYPE_CODE_NUMENTRY: // TYPE_CODE_NUMENTRY: [numentries]
519      // TYPE_CODE_NUMENTRY contains a count of the number of types in the
520      // type list.  This allows us to reserve space.
521      if (Record.size() < 1)
522        return Error("Invalid TYPE_CODE_NUMENTRY record");
523      TypeList.reserve(Record[0]);
524      continue;
525    case bitc::TYPE_CODE_VOID:      // VOID
526      ResultTy = Type::getVoidTy(Context);
527      break;
528    case bitc::TYPE_CODE_FLOAT:     // FLOAT
529      ResultTy = Type::getFloatTy(Context);
530      break;
531    case bitc::TYPE_CODE_DOUBLE:    // DOUBLE
532      ResultTy = Type::getDoubleTy(Context);
533      break;
534    case bitc::TYPE_CODE_X86_FP80:  // X86_FP80
535      ResultTy = Type::getX86_FP80Ty(Context);
536      break;
537    case bitc::TYPE_CODE_FP128:     // FP128
538      ResultTy = Type::getFP128Ty(Context);
539      break;
540    case bitc::TYPE_CODE_PPC_FP128: // PPC_FP128
541      ResultTy = Type::getPPC_FP128Ty(Context);
542      break;
543    case bitc::TYPE_CODE_LABEL:     // LABEL
544      ResultTy = Type::getLabelTy(Context);
545      break;
546    case bitc::TYPE_CODE_OPAQUE:    // OPAQUE
547      ResultTy = 0;
548      break;
549    case bitc::TYPE_CODE_METADATA:  // METADATA
550      ResultTy = Type::getMetadataTy(Context);
551      break;
552    case bitc::TYPE_CODE_INTEGER:   // INTEGER: [width]
553      if (Record.size() < 1)
554        return Error("Invalid Integer type record");
555
556      ResultTy = IntegerType::get(Context, Record[0]);
557      break;
558    case bitc::TYPE_CODE_POINTER: { // POINTER: [pointee type] or
559                                    //          [pointee type, address space]
560      if (Record.size() < 1)
561        return Error("Invalid POINTER type record");
562      unsigned AddressSpace = 0;
563      if (Record.size() == 2)
564        AddressSpace = Record[1];
565      ResultTy = PointerType::get(getTypeByID(Record[0], true),
566                                        AddressSpace);
567      break;
568    }
569    case bitc::TYPE_CODE_FUNCTION: {
570      // FIXME: attrid is dead, remove it in LLVM 3.0
571      // FUNCTION: [vararg, attrid, retty, paramty x N]
572      if (Record.size() < 3)
573        return Error("Invalid FUNCTION type record");
574      std::vector<const Type*> ArgTys;
575      for (unsigned i = 3, e = Record.size(); i != e; ++i)
576        ArgTys.push_back(getTypeByID(Record[i], true));
577
578      ResultTy = FunctionType::get(getTypeByID(Record[2], true), ArgTys,
579                                   Record[0]);
580      break;
581    }
582    case bitc::TYPE_CODE_STRUCT: {  // STRUCT: [ispacked, eltty x N]
583      if (Record.size() < 1)
584        return Error("Invalid STRUCT type record");
585      std::vector<const Type*> EltTys;
586      for (unsigned i = 1, e = Record.size(); i != e; ++i)
587        EltTys.push_back(getTypeByID(Record[i], true));
588      ResultTy = StructType::get(Context, EltTys, Record[0]);
589      break;
590    }
591    case bitc::TYPE_CODE_UNION: {  // UNION: [eltty x N]
592      SmallVector<const Type*, 8> EltTys;
593      for (unsigned i = 0, e = Record.size(); i != e; ++i)
594        EltTys.push_back(getTypeByID(Record[i], true));
595      ResultTy = UnionType::get(&EltTys[0], EltTys.size());
596      break;
597    }
598    case bitc::TYPE_CODE_ARRAY:     // ARRAY: [numelts, eltty]
599      if (Record.size() < 2)
600        return Error("Invalid ARRAY type record");
601      ResultTy = ArrayType::get(getTypeByID(Record[1], true), Record[0]);
602      break;
603    case bitc::TYPE_CODE_VECTOR:    // VECTOR: [numelts, eltty]
604      if (Record.size() < 2)
605        return Error("Invalid VECTOR type record");
606      ResultTy = VectorType::get(getTypeByID(Record[1], true), Record[0]);
607      break;
608    }
609
610    if (NumRecords == TypeList.size()) {
611      // If this is a new type slot, just append it.
612      TypeList.push_back(ResultTy ? ResultTy : OpaqueType::get(Context));
613      ++NumRecords;
614    } else if (ResultTy == 0) {
615      // Otherwise, this was forward referenced, so an opaque type was created,
616      // but the result type is actually just an opaque.  Leave the one we
617      // created previously.
618      ++NumRecords;
619    } else {
620      // Otherwise, this was forward referenced, so an opaque type was created.
621      // Resolve the opaque type to the real type now.
622      assert(NumRecords < TypeList.size() && "Typelist imbalance");
623      const OpaqueType *OldTy = cast<OpaqueType>(TypeList[NumRecords++].get());
624
625      // Don't directly push the new type on the Tab. Instead we want to replace
626      // the opaque type we previously inserted with the new concrete value. The
627      // refinement from the abstract (opaque) type to the new type causes all
628      // uses of the abstract type to use the concrete type (NewTy). This will
629      // also cause the opaque type to be deleted.
630      const_cast<OpaqueType*>(OldTy)->refineAbstractTypeTo(ResultTy);
631
632      // This should have replaced the old opaque type with the new type in the
633      // value table... or with a preexisting type that was already in the
634      // system.  Let's just make sure it did.
635      assert(TypeList[NumRecords-1].get() != OldTy &&
636             "refineAbstractType didn't work!");
637    }
638  }
639}
640
641
642bool BitcodeReader::ParseTypeSymbolTable() {
643  if (Stream.EnterSubBlock(bitc::TYPE_SYMTAB_BLOCK_ID))
644    return Error("Malformed block record");
645
646  SmallVector<uint64_t, 64> Record;
647
648  // Read all the records for this type table.
649  std::string TypeName;
650  while (1) {
651    unsigned Code = Stream.ReadCode();
652    if (Code == bitc::END_BLOCK) {
653      if (Stream.ReadBlockEnd())
654        return Error("Error at end of type symbol table block");
655      return false;
656    }
657
658    if (Code == bitc::ENTER_SUBBLOCK) {
659      // No known subblocks, always skip them.
660      Stream.ReadSubBlockID();
661      if (Stream.SkipBlock())
662        return Error("Malformed block record");
663      continue;
664    }
665
666    if (Code == bitc::DEFINE_ABBREV) {
667      Stream.ReadAbbrevRecord();
668      continue;
669    }
670
671    // Read a record.
672    Record.clear();
673    switch (Stream.ReadRecord(Code, Record)) {
674    default:  // Default behavior: unknown type.
675      break;
676    case bitc::TST_CODE_ENTRY:    // TST_ENTRY: [typeid, namechar x N]
677      if (ConvertToString(Record, 1, TypeName))
678        return Error("Invalid TST_ENTRY record");
679      unsigned TypeID = Record[0];
680      if (TypeID >= TypeList.size())
681        return Error("Invalid Type ID in TST_ENTRY record");
682
683      TheModule->addTypeName(TypeName, TypeList[TypeID].get());
684      TypeName.clear();
685      break;
686    }
687  }
688}
689
690bool BitcodeReader::ParseValueSymbolTable() {
691  if (Stream.EnterSubBlock(bitc::VALUE_SYMTAB_BLOCK_ID))
692    return Error("Malformed block record");
693
694  SmallVector<uint64_t, 64> Record;
695
696  // Read all the records for this value table.
697  SmallString<128> ValueName;
698  while (1) {
699    unsigned Code = Stream.ReadCode();
700    if (Code == bitc::END_BLOCK) {
701      if (Stream.ReadBlockEnd())
702        return Error("Error at end of value symbol table block");
703      return false;
704    }
705    if (Code == bitc::ENTER_SUBBLOCK) {
706      // No known subblocks, always skip them.
707      Stream.ReadSubBlockID();
708      if (Stream.SkipBlock())
709        return Error("Malformed block record");
710      continue;
711    }
712
713    if (Code == bitc::DEFINE_ABBREV) {
714      Stream.ReadAbbrevRecord();
715      continue;
716    }
717
718    // Read a record.
719    Record.clear();
720    switch (Stream.ReadRecord(Code, Record)) {
721    default:  // Default behavior: unknown type.
722      break;
723    case bitc::VST_CODE_ENTRY: {  // VST_ENTRY: [valueid, namechar x N]
724      if (ConvertToString(Record, 1, ValueName))
725        return Error("Invalid VST_ENTRY record");
726      unsigned ValueID = Record[0];
727      if (ValueID >= ValueList.size())
728        return Error("Invalid Value ID in VST_ENTRY record");
729      Value *V = ValueList[ValueID];
730
731      V->setName(StringRef(ValueName.data(), ValueName.size()));
732      ValueName.clear();
733      break;
734    }
735    case bitc::VST_CODE_BBENTRY: {
736      if (ConvertToString(Record, 1, ValueName))
737        return Error("Invalid VST_BBENTRY record");
738      BasicBlock *BB = getBasicBlock(Record[0]);
739      if (BB == 0)
740        return Error("Invalid BB ID in VST_BBENTRY record");
741
742      BB->setName(StringRef(ValueName.data(), ValueName.size()));
743      ValueName.clear();
744      break;
745    }
746    }
747  }
748}
749
750bool BitcodeReader::ParseMetadata() {
751  unsigned NextMDValueNo = MDValueList.size();
752
753  if (Stream.EnterSubBlock(bitc::METADATA_BLOCK_ID))
754    return Error("Malformed block record");
755
756  SmallVector<uint64_t, 64> Record;
757
758  // Read all the records.
759  while (1) {
760    unsigned Code = Stream.ReadCode();
761    if (Code == bitc::END_BLOCK) {
762      if (Stream.ReadBlockEnd())
763        return Error("Error at end of PARAMATTR block");
764      return false;
765    }
766
767    if (Code == bitc::ENTER_SUBBLOCK) {
768      // No known subblocks, always skip them.
769      Stream.ReadSubBlockID();
770      if (Stream.SkipBlock())
771        return Error("Malformed block record");
772      continue;
773    }
774
775    if (Code == bitc::DEFINE_ABBREV) {
776      Stream.ReadAbbrevRecord();
777      continue;
778    }
779
780    bool IsFunctionLocal = false;
781    // Read a record.
782    Record.clear();
783    switch (Stream.ReadRecord(Code, Record)) {
784    default:  // Default behavior: ignore.
785      break;
786    case bitc::METADATA_NAME: {
787      // Read named of the named metadata.
788      unsigned NameLength = Record.size();
789      SmallString<8> Name;
790      Name.resize(NameLength);
791      for (unsigned i = 0; i != NameLength; ++i)
792        Name[i] = Record[i];
793      Record.clear();
794      Code = Stream.ReadCode();
795
796      // METADATA_NAME is always followed by METADATA_NAMED_NODE.
797      if (Stream.ReadRecord(Code, Record) != bitc::METADATA_NAMED_NODE)
798        assert ( 0 && "Inavlid Named Metadata record");
799
800      // Read named metadata elements.
801      unsigned Size = Record.size();
802      SmallVector<MDNode *, 8> Elts;
803      for (unsigned i = 0; i != Size; ++i) {
804        if (Record[i] == ~0U) {
805          Elts.push_back(NULL);
806          continue;
807        }
808        MDNode *MD = dyn_cast<MDNode>(MDValueList.getValueFwdRef(Record[i]));
809        if (MD == 0)
810          return Error("Malformed metadata record");
811        Elts.push_back(MD);
812      }
813      Value *V = NamedMDNode::Create(Context, Name.str(), Elts.data(),
814                                     Elts.size(), TheModule);
815      MDValueList.AssignValue(V, NextMDValueNo++);
816      break;
817    }
818    case bitc::METADATA_FN_NODE:
819      IsFunctionLocal = true;
820      // fall-through
821    case bitc::METADATA_NODE: {
822      if (Record.empty() || Record.size() % 2 == 1)
823        return Error("Invalid METADATA_NODE record");
824
825      unsigned Size = Record.size();
826      SmallVector<Value*, 8> Elts;
827      for (unsigned i = 0; i != Size; i += 2) {
828        const Type *Ty = getTypeByID(Record[i], false);
829        if (Ty->isMetadataTy())
830          Elts.push_back(MDValueList.getValueFwdRef(Record[i+1]));
831        else if (!Ty->isVoidTy())
832          Elts.push_back(ValueList.getValueFwdRef(Record[i+1], Ty));
833        else
834          Elts.push_back(NULL);
835      }
836      Value *V = MDNode::getWhenValsUnresolved(Context, &Elts[0], Elts.size(),
837                                               IsFunctionLocal);
838      IsFunctionLocal = false;
839      MDValueList.AssignValue(V, NextMDValueNo++);
840      break;
841    }
842    case bitc::METADATA_STRING: {
843      unsigned MDStringLength = Record.size();
844      SmallString<8> String;
845      String.resize(MDStringLength);
846      for (unsigned i = 0; i != MDStringLength; ++i)
847        String[i] = Record[i];
848      Value *V = MDString::get(Context,
849                               StringRef(String.data(), String.size()));
850      MDValueList.AssignValue(V, NextMDValueNo++);
851      break;
852    }
853    case bitc::METADATA_KIND: {
854      unsigned RecordLength = Record.size();
855      if (Record.empty() || RecordLength < 2)
856        return Error("Invalid METADATA_KIND record");
857      SmallString<8> Name;
858      Name.resize(RecordLength-1);
859      unsigned Kind = Record[0];
860      (void) Kind;
861      for (unsigned i = 1; i != RecordLength; ++i)
862        Name[i-1] = Record[i];
863
864      unsigned NewKind = TheModule->getMDKindID(Name.str());
865      assert(Kind == NewKind &&
866             "FIXME: Unable to handle custom metadata mismatch!");(void)NewKind;
867      break;
868    }
869    }
870  }
871}
872
873/// DecodeSignRotatedValue - Decode a signed value stored with the sign bit in
874/// the LSB for dense VBR encoding.
875static uint64_t DecodeSignRotatedValue(uint64_t V) {
876  if ((V & 1) == 0)
877    return V >> 1;
878  if (V != 1)
879    return -(V >> 1);
880  // There is no such thing as -0 with integers.  "-0" really means MININT.
881  return 1ULL << 63;
882}
883
884/// ResolveGlobalAndAliasInits - Resolve all of the initializers for global
885/// values and aliases that we can.
886bool BitcodeReader::ResolveGlobalAndAliasInits() {
887  std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInitWorklist;
888  std::vector<std::pair<GlobalAlias*, unsigned> > AliasInitWorklist;
889
890  GlobalInitWorklist.swap(GlobalInits);
891  AliasInitWorklist.swap(AliasInits);
892
893  while (!GlobalInitWorklist.empty()) {
894    unsigned ValID = GlobalInitWorklist.back().second;
895    if (ValID >= ValueList.size()) {
896      // Not ready to resolve this yet, it requires something later in the file.
897      GlobalInits.push_back(GlobalInitWorklist.back());
898    } else {
899      if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
900        GlobalInitWorklist.back().first->setInitializer(C);
901      else
902        return Error("Global variable initializer is not a constant!");
903    }
904    GlobalInitWorklist.pop_back();
905  }
906
907  while (!AliasInitWorklist.empty()) {
908    unsigned ValID = AliasInitWorklist.back().second;
909    if (ValID >= ValueList.size()) {
910      AliasInits.push_back(AliasInitWorklist.back());
911    } else {
912      if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
913        AliasInitWorklist.back().first->setAliasee(C);
914      else
915        return Error("Alias initializer is not a constant!");
916    }
917    AliasInitWorklist.pop_back();
918  }
919  return false;
920}
921
922bool BitcodeReader::ParseConstants() {
923  if (Stream.EnterSubBlock(bitc::CONSTANTS_BLOCK_ID))
924    return Error("Malformed block record");
925
926  SmallVector<uint64_t, 64> Record;
927
928  // Read all the records for this value table.
929  const Type *CurTy = Type::getInt32Ty(Context);
930  unsigned NextCstNo = ValueList.size();
931  while (1) {
932    unsigned Code = Stream.ReadCode();
933    if (Code == bitc::END_BLOCK)
934      break;
935
936    if (Code == bitc::ENTER_SUBBLOCK) {
937      // No known subblocks, always skip them.
938      Stream.ReadSubBlockID();
939      if (Stream.SkipBlock())
940        return Error("Malformed block record");
941      continue;
942    }
943
944    if (Code == bitc::DEFINE_ABBREV) {
945      Stream.ReadAbbrevRecord();
946      continue;
947    }
948
949    // Read a record.
950    Record.clear();
951    Value *V = 0;
952    unsigned BitCode = Stream.ReadRecord(Code, Record);
953    switch (BitCode) {
954    default:  // Default behavior: unknown constant
955    case bitc::CST_CODE_UNDEF:     // UNDEF
956      V = UndefValue::get(CurTy);
957      break;
958    case bitc::CST_CODE_SETTYPE:   // SETTYPE: [typeid]
959      if (Record.empty())
960        return Error("Malformed CST_SETTYPE record");
961      if (Record[0] >= TypeList.size())
962        return Error("Invalid Type ID in CST_SETTYPE record");
963      CurTy = TypeList[Record[0]];
964      continue;  // Skip the ValueList manipulation.
965    case bitc::CST_CODE_NULL:      // NULL
966      V = Constant::getNullValue(CurTy);
967      break;
968    case bitc::CST_CODE_INTEGER:   // INTEGER: [intval]
969      if (!CurTy->isIntegerTy() || Record.empty())
970        return Error("Invalid CST_INTEGER record");
971      V = ConstantInt::get(CurTy, DecodeSignRotatedValue(Record[0]));
972      break;
973    case bitc::CST_CODE_WIDE_INTEGER: {// WIDE_INTEGER: [n x intval]
974      if (!CurTy->isIntegerTy() || Record.empty())
975        return Error("Invalid WIDE_INTEGER record");
976
977      unsigned NumWords = Record.size();
978      SmallVector<uint64_t, 8> Words;
979      Words.resize(NumWords);
980      for (unsigned i = 0; i != NumWords; ++i)
981        Words[i] = DecodeSignRotatedValue(Record[i]);
982      V = ConstantInt::get(Context,
983                           APInt(cast<IntegerType>(CurTy)->getBitWidth(),
984                           NumWords, &Words[0]));
985      break;
986    }
987    case bitc::CST_CODE_FLOAT: {    // FLOAT: [fpval]
988      if (Record.empty())
989        return Error("Invalid FLOAT record");
990      if (CurTy->isFloatTy())
991        V = ConstantFP::get(Context, APFloat(APInt(32, (uint32_t)Record[0])));
992      else if (CurTy->isDoubleTy())
993        V = ConstantFP::get(Context, APFloat(APInt(64, Record[0])));
994      else if (CurTy->isX86_FP80Ty()) {
995        // Bits are not stored the same way as a normal i80 APInt, compensate.
996        uint64_t Rearrange[2];
997        Rearrange[0] = (Record[1] & 0xffffLL) | (Record[0] << 16);
998        Rearrange[1] = Record[0] >> 48;
999        V = ConstantFP::get(Context, APFloat(APInt(80, 2, Rearrange)));
1000      } else if (CurTy->isFP128Ty())
1001        V = ConstantFP::get(Context, APFloat(APInt(128, 2, &Record[0]), true));
1002      else if (CurTy->isPPC_FP128Ty())
1003        V = ConstantFP::get(Context, APFloat(APInt(128, 2, &Record[0])));
1004      else
1005        V = UndefValue::get(CurTy);
1006      break;
1007    }
1008
1009    case bitc::CST_CODE_AGGREGATE: {// AGGREGATE: [n x value number]
1010      if (Record.empty())
1011        return Error("Invalid CST_AGGREGATE record");
1012
1013      unsigned Size = Record.size();
1014      std::vector<Constant*> Elts;
1015
1016      if (const StructType *STy = dyn_cast<StructType>(CurTy)) {
1017        for (unsigned i = 0; i != Size; ++i)
1018          Elts.push_back(ValueList.getConstantFwdRef(Record[i],
1019                                                     STy->getElementType(i)));
1020        V = ConstantStruct::get(STy, Elts);
1021      } else if (const UnionType *UnTy = dyn_cast<UnionType>(CurTy)) {
1022        uint64_t Index = Record[0];
1023        Constant *Val = ValueList.getConstantFwdRef(Record[1],
1024                                        UnTy->getElementType(Index));
1025        V = ConstantUnion::get(UnTy, Val);
1026      } else if (const ArrayType *ATy = dyn_cast<ArrayType>(CurTy)) {
1027        const Type *EltTy = ATy->getElementType();
1028        for (unsigned i = 0; i != Size; ++i)
1029          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
1030        V = ConstantArray::get(ATy, Elts);
1031      } else if (const VectorType *VTy = dyn_cast<VectorType>(CurTy)) {
1032        const Type *EltTy = VTy->getElementType();
1033        for (unsigned i = 0; i != Size; ++i)
1034          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
1035        V = ConstantVector::get(Elts);
1036      } else {
1037        V = UndefValue::get(CurTy);
1038      }
1039      break;
1040    }
1041    case bitc::CST_CODE_STRING: { // STRING: [values]
1042      if (Record.empty())
1043        return Error("Invalid CST_AGGREGATE record");
1044
1045      const ArrayType *ATy = cast<ArrayType>(CurTy);
1046      const Type *EltTy = ATy->getElementType();
1047
1048      unsigned Size = Record.size();
1049      std::vector<Constant*> Elts;
1050      for (unsigned i = 0; i != Size; ++i)
1051        Elts.push_back(ConstantInt::get(EltTy, Record[i]));
1052      V = ConstantArray::get(ATy, Elts);
1053      break;
1054    }
1055    case bitc::CST_CODE_CSTRING: { // CSTRING: [values]
1056      if (Record.empty())
1057        return Error("Invalid CST_AGGREGATE record");
1058
1059      const ArrayType *ATy = cast<ArrayType>(CurTy);
1060      const Type *EltTy = ATy->getElementType();
1061
1062      unsigned Size = Record.size();
1063      std::vector<Constant*> Elts;
1064      for (unsigned i = 0; i != Size; ++i)
1065        Elts.push_back(ConstantInt::get(EltTy, Record[i]));
1066      Elts.push_back(Constant::getNullValue(EltTy));
1067      V = ConstantArray::get(ATy, Elts);
1068      break;
1069    }
1070    case bitc::CST_CODE_CE_BINOP: {  // CE_BINOP: [opcode, opval, opval]
1071      if (Record.size() < 3) return Error("Invalid CE_BINOP record");
1072      int Opc = GetDecodedBinaryOpcode(Record[0], CurTy);
1073      if (Opc < 0) {
1074        V = UndefValue::get(CurTy);  // Unknown binop.
1075      } else {
1076        Constant *LHS = ValueList.getConstantFwdRef(Record[1], CurTy);
1077        Constant *RHS = ValueList.getConstantFwdRef(Record[2], CurTy);
1078        unsigned Flags = 0;
1079        if (Record.size() >= 4) {
1080          if (Opc == Instruction::Add ||
1081              Opc == Instruction::Sub ||
1082              Opc == Instruction::Mul) {
1083            if (Record[3] & (1 << bitc::OBO_NO_SIGNED_WRAP))
1084              Flags |= OverflowingBinaryOperator::NoSignedWrap;
1085            if (Record[3] & (1 << bitc::OBO_NO_UNSIGNED_WRAP))
1086              Flags |= OverflowingBinaryOperator::NoUnsignedWrap;
1087          } else if (Opc == Instruction::SDiv) {
1088            if (Record[3] & (1 << bitc::SDIV_EXACT))
1089              Flags |= SDivOperator::IsExact;
1090          }
1091        }
1092        V = ConstantExpr::get(Opc, LHS, RHS, Flags);
1093      }
1094      break;
1095    }
1096    case bitc::CST_CODE_CE_CAST: {  // CE_CAST: [opcode, opty, opval]
1097      if (Record.size() < 3) return Error("Invalid CE_CAST record");
1098      int Opc = GetDecodedCastOpcode(Record[0]);
1099      if (Opc < 0) {
1100        V = UndefValue::get(CurTy);  // Unknown cast.
1101      } else {
1102        const Type *OpTy = getTypeByID(Record[1]);
1103        if (!OpTy) return Error("Invalid CE_CAST record");
1104        Constant *Op = ValueList.getConstantFwdRef(Record[2], OpTy);
1105        V = ConstantExpr::getCast(Opc, Op, CurTy);
1106      }
1107      break;
1108    }
1109    case bitc::CST_CODE_CE_INBOUNDS_GEP:
1110    case bitc::CST_CODE_CE_GEP: {  // CE_GEP:        [n x operands]
1111      if (Record.size() & 1) return Error("Invalid CE_GEP record");
1112      SmallVector<Constant*, 16> Elts;
1113      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
1114        const Type *ElTy = getTypeByID(Record[i]);
1115        if (!ElTy) return Error("Invalid CE_GEP record");
1116        Elts.push_back(ValueList.getConstantFwdRef(Record[i+1], ElTy));
1117      }
1118      if (BitCode == bitc::CST_CODE_CE_INBOUNDS_GEP)
1119        V = ConstantExpr::getInBoundsGetElementPtr(Elts[0], &Elts[1],
1120                                                   Elts.size()-1);
1121      else
1122        V = ConstantExpr::getGetElementPtr(Elts[0], &Elts[1],
1123                                           Elts.size()-1);
1124      break;
1125    }
1126    case bitc::CST_CODE_CE_SELECT:  // CE_SELECT: [opval#, opval#, opval#]
1127      if (Record.size() < 3) return Error("Invalid CE_SELECT record");
1128      V = ConstantExpr::getSelect(ValueList.getConstantFwdRef(Record[0],
1129                                                              Type::getInt1Ty(Context)),
1130                                  ValueList.getConstantFwdRef(Record[1],CurTy),
1131                                  ValueList.getConstantFwdRef(Record[2],CurTy));
1132      break;
1133    case bitc::CST_CODE_CE_EXTRACTELT: { // CE_EXTRACTELT: [opty, opval, opval]
1134      if (Record.size() < 3) return Error("Invalid CE_EXTRACTELT record");
1135      const VectorType *OpTy =
1136        dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
1137      if (OpTy == 0) return Error("Invalid CE_EXTRACTELT record");
1138      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1139      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], Type::getInt32Ty(Context));
1140      V = ConstantExpr::getExtractElement(Op0, Op1);
1141      break;
1142    }
1143    case bitc::CST_CODE_CE_INSERTELT: { // CE_INSERTELT: [opval, opval, opval]
1144      const VectorType *OpTy = dyn_cast<VectorType>(CurTy);
1145      if (Record.size() < 3 || OpTy == 0)
1146        return Error("Invalid CE_INSERTELT record");
1147      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
1148      Constant *Op1 = ValueList.getConstantFwdRef(Record[1],
1149                                                  OpTy->getElementType());
1150      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], Type::getInt32Ty(Context));
1151      V = ConstantExpr::getInsertElement(Op0, Op1, Op2);
1152      break;
1153    }
1154    case bitc::CST_CODE_CE_SHUFFLEVEC: { // CE_SHUFFLEVEC: [opval, opval, opval]
1155      const VectorType *OpTy = dyn_cast<VectorType>(CurTy);
1156      if (Record.size() < 3 || OpTy == 0)
1157        return Error("Invalid CE_SHUFFLEVEC record");
1158      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
1159      Constant *Op1 = ValueList.getConstantFwdRef(Record[1], OpTy);
1160      const Type *ShufTy = VectorType::get(Type::getInt32Ty(Context),
1161                                                 OpTy->getNumElements());
1162      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], ShufTy);
1163      V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
1164      break;
1165    }
1166    case bitc::CST_CODE_CE_SHUFVEC_EX: { // [opty, opval, opval, opval]
1167      const VectorType *RTy = dyn_cast<VectorType>(CurTy);
1168      const VectorType *OpTy = dyn_cast<VectorType>(getTypeByID(Record[0]));
1169      if (Record.size() < 4 || RTy == 0 || OpTy == 0)
1170        return Error("Invalid CE_SHUFVEC_EX record");
1171      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1172      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
1173      const Type *ShufTy = VectorType::get(Type::getInt32Ty(Context),
1174                                                 RTy->getNumElements());
1175      Constant *Op2 = ValueList.getConstantFwdRef(Record[3], ShufTy);
1176      V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
1177      break;
1178    }
1179    case bitc::CST_CODE_CE_CMP: {     // CE_CMP: [opty, opval, opval, pred]
1180      if (Record.size() < 4) return Error("Invalid CE_CMP record");
1181      const Type *OpTy = getTypeByID(Record[0]);
1182      if (OpTy == 0) return Error("Invalid CE_CMP record");
1183      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1184      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
1185
1186      if (OpTy->isFPOrFPVectorTy())
1187        V = ConstantExpr::getFCmp(Record[3], Op0, Op1);
1188      else
1189        V = ConstantExpr::getICmp(Record[3], Op0, Op1);
1190      break;
1191    }
1192    case bitc::CST_CODE_INLINEASM: {
1193      if (Record.size() < 2) return Error("Invalid INLINEASM record");
1194      std::string AsmStr, ConstrStr;
1195      bool HasSideEffects = Record[0] & 1;
1196      bool IsAlignStack = Record[0] >> 1;
1197      unsigned AsmStrSize = Record[1];
1198      if (2+AsmStrSize >= Record.size())
1199        return Error("Invalid INLINEASM record");
1200      unsigned ConstStrSize = Record[2+AsmStrSize];
1201      if (3+AsmStrSize+ConstStrSize > Record.size())
1202        return Error("Invalid INLINEASM record");
1203
1204      for (unsigned i = 0; i != AsmStrSize; ++i)
1205        AsmStr += (char)Record[2+i];
1206      for (unsigned i = 0; i != ConstStrSize; ++i)
1207        ConstrStr += (char)Record[3+AsmStrSize+i];
1208      const PointerType *PTy = cast<PointerType>(CurTy);
1209      V = InlineAsm::get(cast<FunctionType>(PTy->getElementType()),
1210                         AsmStr, ConstrStr, HasSideEffects, IsAlignStack);
1211      break;
1212    }
1213    case bitc::CST_CODE_BLOCKADDRESS:{
1214      if (Record.size() < 3) return Error("Invalid CE_BLOCKADDRESS record");
1215      const Type *FnTy = getTypeByID(Record[0]);
1216      if (FnTy == 0) return Error("Invalid CE_BLOCKADDRESS record");
1217      Function *Fn =
1218        dyn_cast_or_null<Function>(ValueList.getConstantFwdRef(Record[1],FnTy));
1219      if (Fn == 0) return Error("Invalid CE_BLOCKADDRESS record");
1220
1221      GlobalVariable *FwdRef = new GlobalVariable(*Fn->getParent(),
1222                                                  Type::getInt8Ty(Context),
1223                                            false, GlobalValue::InternalLinkage,
1224                                                  0, "");
1225      BlockAddrFwdRefs[Fn].push_back(std::make_pair(Record[2], FwdRef));
1226      V = FwdRef;
1227      break;
1228    }
1229    }
1230
1231    ValueList.AssignValue(V, NextCstNo);
1232    ++NextCstNo;
1233  }
1234
1235  if (NextCstNo != ValueList.size())
1236    return Error("Invalid constant reference!");
1237
1238  if (Stream.ReadBlockEnd())
1239    return Error("Error at end of constants block");
1240
1241  // Once all the constants have been read, go through and resolve forward
1242  // references.
1243  ValueList.ResolveConstantForwardRefs();
1244  return false;
1245}
1246
1247/// RememberAndSkipFunctionBody - When we see the block for a function body,
1248/// remember where it is and then skip it.  This lets us lazily deserialize the
1249/// functions.
1250bool BitcodeReader::RememberAndSkipFunctionBody() {
1251  // Get the function we are talking about.
1252  if (FunctionsWithBodies.empty())
1253    return Error("Insufficient function protos");
1254
1255  Function *Fn = FunctionsWithBodies.back();
1256  FunctionsWithBodies.pop_back();
1257
1258  // Save the current stream state.
1259  uint64_t CurBit = Stream.GetCurrentBitNo();
1260  DeferredFunctionInfo[Fn] = CurBit;
1261
1262  // Skip over the function block for now.
1263  if (Stream.SkipBlock())
1264    return Error("Malformed block record");
1265  return false;
1266}
1267
1268bool BitcodeReader::ParseModule() {
1269  if (Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
1270    return Error("Malformed block record");
1271
1272  SmallVector<uint64_t, 64> Record;
1273  std::vector<std::string> SectionTable;
1274  std::vector<std::string> GCTable;
1275
1276  // Read all the records for this module.
1277  while (!Stream.AtEndOfStream()) {
1278    unsigned Code = Stream.ReadCode();
1279    if (Code == bitc::END_BLOCK) {
1280      if (Stream.ReadBlockEnd())
1281        return Error("Error at end of module block");
1282
1283      // Patch the initializers for globals and aliases up.
1284      ResolveGlobalAndAliasInits();
1285      if (!GlobalInits.empty() || !AliasInits.empty())
1286        return Error("Malformed global initializer set");
1287      if (!FunctionsWithBodies.empty())
1288        return Error("Too few function bodies found");
1289
1290      // Look for intrinsic functions which need to be upgraded at some point
1291      for (Module::iterator FI = TheModule->begin(), FE = TheModule->end();
1292           FI != FE; ++FI) {
1293        Function* NewFn;
1294        if (UpgradeIntrinsicFunction(FI, NewFn))
1295          UpgradedIntrinsics.push_back(std::make_pair(FI, NewFn));
1296      }
1297
1298      // Force deallocation of memory for these vectors to favor the client that
1299      // want lazy deserialization.
1300      std::vector<std::pair<GlobalVariable*, unsigned> >().swap(GlobalInits);
1301      std::vector<std::pair<GlobalAlias*, unsigned> >().swap(AliasInits);
1302      std::vector<Function*>().swap(FunctionsWithBodies);
1303      return false;
1304    }
1305
1306    if (Code == bitc::ENTER_SUBBLOCK) {
1307      switch (Stream.ReadSubBlockID()) {
1308      default:  // Skip unknown content.
1309        if (Stream.SkipBlock())
1310          return Error("Malformed block record");
1311        break;
1312      case bitc::BLOCKINFO_BLOCK_ID:
1313        if (Stream.ReadBlockInfoBlock())
1314          return Error("Malformed BlockInfoBlock");
1315        break;
1316      case bitc::PARAMATTR_BLOCK_ID:
1317        if (ParseAttributeBlock())
1318          return true;
1319        break;
1320      case bitc::TYPE_BLOCK_ID:
1321        if (ParseTypeTable())
1322          return true;
1323        break;
1324      case bitc::TYPE_SYMTAB_BLOCK_ID:
1325        if (ParseTypeSymbolTable())
1326          return true;
1327        break;
1328      case bitc::VALUE_SYMTAB_BLOCK_ID:
1329        if (ParseValueSymbolTable())
1330          return true;
1331        break;
1332      case bitc::CONSTANTS_BLOCK_ID:
1333        if (ParseConstants() || ResolveGlobalAndAliasInits())
1334          return true;
1335        break;
1336      case bitc::METADATA_BLOCK_ID:
1337        if (ParseMetadata())
1338          return true;
1339        break;
1340      case bitc::FUNCTION_BLOCK_ID:
1341        // If this is the first function body we've seen, reverse the
1342        // FunctionsWithBodies list.
1343        if (!HasReversedFunctionsWithBodies) {
1344          std::reverse(FunctionsWithBodies.begin(), FunctionsWithBodies.end());
1345          HasReversedFunctionsWithBodies = true;
1346        }
1347
1348        if (RememberAndSkipFunctionBody())
1349          return true;
1350        break;
1351      }
1352      continue;
1353    }
1354
1355    if (Code == bitc::DEFINE_ABBREV) {
1356      Stream.ReadAbbrevRecord();
1357      continue;
1358    }
1359
1360    // Read a record.
1361    switch (Stream.ReadRecord(Code, Record)) {
1362    default: break;  // Default behavior, ignore unknown content.
1363    case bitc::MODULE_CODE_VERSION:  // VERSION: [version#]
1364      if (Record.size() < 1)
1365        return Error("Malformed MODULE_CODE_VERSION");
1366      // Only version #0 is supported so far.
1367      if (Record[0] != 0)
1368        return Error("Unknown bitstream version!");
1369      break;
1370    case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
1371      std::string S;
1372      if (ConvertToString(Record, 0, S))
1373        return Error("Invalid MODULE_CODE_TRIPLE record");
1374      TheModule->setTargetTriple(S);
1375      break;
1376    }
1377    case bitc::MODULE_CODE_DATALAYOUT: {  // DATALAYOUT: [strchr x N]
1378      std::string S;
1379      if (ConvertToString(Record, 0, S))
1380        return Error("Invalid MODULE_CODE_DATALAYOUT record");
1381      TheModule->setDataLayout(S);
1382      break;
1383    }
1384    case bitc::MODULE_CODE_ASM: {  // ASM: [strchr x N]
1385      std::string S;
1386      if (ConvertToString(Record, 0, S))
1387        return Error("Invalid MODULE_CODE_ASM record");
1388      TheModule->setModuleInlineAsm(S);
1389      break;
1390    }
1391    case bitc::MODULE_CODE_DEPLIB: {  // DEPLIB: [strchr x N]
1392      std::string S;
1393      if (ConvertToString(Record, 0, S))
1394        return Error("Invalid MODULE_CODE_DEPLIB record");
1395      TheModule->addLibrary(S);
1396      break;
1397    }
1398    case bitc::MODULE_CODE_SECTIONNAME: {  // SECTIONNAME: [strchr x N]
1399      std::string S;
1400      if (ConvertToString(Record, 0, S))
1401        return Error("Invalid MODULE_CODE_SECTIONNAME record");
1402      SectionTable.push_back(S);
1403      break;
1404    }
1405    case bitc::MODULE_CODE_GCNAME: {  // SECTIONNAME: [strchr x N]
1406      std::string S;
1407      if (ConvertToString(Record, 0, S))
1408        return Error("Invalid MODULE_CODE_GCNAME record");
1409      GCTable.push_back(S);
1410      break;
1411    }
1412    // GLOBALVAR: [pointer type, isconst, initid,
1413    //             linkage, alignment, section, visibility, threadlocal]
1414    case bitc::MODULE_CODE_GLOBALVAR: {
1415      if (Record.size() < 6)
1416        return Error("Invalid MODULE_CODE_GLOBALVAR record");
1417      const Type *Ty = getTypeByID(Record[0]);
1418      if (!Ty->isPointerTy())
1419        return Error("Global not a pointer type!");
1420      unsigned AddressSpace = cast<PointerType>(Ty)->getAddressSpace();
1421      Ty = cast<PointerType>(Ty)->getElementType();
1422
1423      bool isConstant = Record[1];
1424      GlobalValue::LinkageTypes Linkage = GetDecodedLinkage(Record[3]);
1425      unsigned Alignment = (1 << Record[4]) >> 1;
1426      std::string Section;
1427      if (Record[5]) {
1428        if (Record[5]-1 >= SectionTable.size())
1429          return Error("Invalid section ID");
1430        Section = SectionTable[Record[5]-1];
1431      }
1432      GlobalValue::VisibilityTypes Visibility = GlobalValue::DefaultVisibility;
1433      if (Record.size() > 6)
1434        Visibility = GetDecodedVisibility(Record[6]);
1435      bool isThreadLocal = false;
1436      if (Record.size() > 7)
1437        isThreadLocal = Record[7];
1438
1439      GlobalVariable *NewGV =
1440        new GlobalVariable(*TheModule, Ty, isConstant, Linkage, 0, "", 0,
1441                           isThreadLocal, AddressSpace);
1442      NewGV->setAlignment(Alignment);
1443      if (!Section.empty())
1444        NewGV->setSection(Section);
1445      NewGV->setVisibility(Visibility);
1446      NewGV->setThreadLocal(isThreadLocal);
1447
1448      ValueList.push_back(NewGV);
1449
1450      // Remember which value to use for the global initializer.
1451      if (unsigned InitID = Record[2])
1452        GlobalInits.push_back(std::make_pair(NewGV, InitID-1));
1453      break;
1454    }
1455    // FUNCTION:  [type, callingconv, isproto, linkage, paramattr,
1456    //             alignment, section, visibility, gc]
1457    case bitc::MODULE_CODE_FUNCTION: {
1458      if (Record.size() < 8)
1459        return Error("Invalid MODULE_CODE_FUNCTION record");
1460      const Type *Ty = getTypeByID(Record[0]);
1461      if (!Ty->isPointerTy())
1462        return Error("Function not a pointer type!");
1463      const FunctionType *FTy =
1464        dyn_cast<FunctionType>(cast<PointerType>(Ty)->getElementType());
1465      if (!FTy)
1466        return Error("Function not a pointer to function type!");
1467
1468      Function *Func = Function::Create(FTy, GlobalValue::ExternalLinkage,
1469                                        "", TheModule);
1470
1471      Func->setCallingConv(static_cast<CallingConv::ID>(Record[1]));
1472      bool isProto = Record[2];
1473      Func->setLinkage(GetDecodedLinkage(Record[3]));
1474      Func->setAttributes(getAttributes(Record[4]));
1475
1476      Func->setAlignment((1 << Record[5]) >> 1);
1477      if (Record[6]) {
1478        if (Record[6]-1 >= SectionTable.size())
1479          return Error("Invalid section ID");
1480        Func->setSection(SectionTable[Record[6]-1]);
1481      }
1482      Func->setVisibility(GetDecodedVisibility(Record[7]));
1483      if (Record.size() > 8 && Record[8]) {
1484        if (Record[8]-1 > GCTable.size())
1485          return Error("Invalid GC ID");
1486        Func->setGC(GCTable[Record[8]-1].c_str());
1487      }
1488      ValueList.push_back(Func);
1489
1490      // If this is a function with a body, remember the prototype we are
1491      // creating now, so that we can match up the body with them later.
1492      if (!isProto)
1493        FunctionsWithBodies.push_back(Func);
1494      break;
1495    }
1496    // ALIAS: [alias type, aliasee val#, linkage]
1497    // ALIAS: [alias type, aliasee val#, linkage, visibility]
1498    case bitc::MODULE_CODE_ALIAS: {
1499      if (Record.size() < 3)
1500        return Error("Invalid MODULE_ALIAS record");
1501      const Type *Ty = getTypeByID(Record[0]);
1502      if (!Ty->isPointerTy())
1503        return Error("Function not a pointer type!");
1504
1505      GlobalAlias *NewGA = new GlobalAlias(Ty, GetDecodedLinkage(Record[2]),
1506                                           "", 0, TheModule);
1507      // Old bitcode files didn't have visibility field.
1508      if (Record.size() > 3)
1509        NewGA->setVisibility(GetDecodedVisibility(Record[3]));
1510      ValueList.push_back(NewGA);
1511      AliasInits.push_back(std::make_pair(NewGA, Record[1]));
1512      break;
1513    }
1514    /// MODULE_CODE_PURGEVALS: [numvals]
1515    case bitc::MODULE_CODE_PURGEVALS:
1516      // Trim down the value list to the specified size.
1517      if (Record.size() < 1 || Record[0] > ValueList.size())
1518        return Error("Invalid MODULE_PURGEVALS record");
1519      ValueList.shrinkTo(Record[0]);
1520      break;
1521    }
1522    Record.clear();
1523  }
1524
1525  return Error("Premature end of bitstream");
1526}
1527
1528bool BitcodeReader::ParseBitcodeInto(Module *M) {
1529  TheModule = 0;
1530
1531  unsigned char *BufPtr = (unsigned char *)Buffer->getBufferStart();
1532  unsigned char *BufEnd = BufPtr+Buffer->getBufferSize();
1533
1534  if (Buffer->getBufferSize() & 3) {
1535    if (!isRawBitcode(BufPtr, BufEnd) && !isBitcodeWrapper(BufPtr, BufEnd))
1536      return Error("Invalid bitcode signature");
1537    else
1538      return Error("Bitcode stream should be a multiple of 4 bytes in length");
1539  }
1540
1541  // If we have a wrapper header, parse it and ignore the non-bc file contents.
1542  // The magic number is 0x0B17C0DE stored in little endian.
1543  if (isBitcodeWrapper(BufPtr, BufEnd))
1544    if (SkipBitcodeWrapperHeader(BufPtr, BufEnd))
1545      return Error("Invalid bitcode wrapper header");
1546
1547  StreamFile.init(BufPtr, BufEnd);
1548  Stream.init(StreamFile);
1549
1550  // Sniff for the signature.
1551  if (Stream.Read(8) != 'B' ||
1552      Stream.Read(8) != 'C' ||
1553      Stream.Read(4) != 0x0 ||
1554      Stream.Read(4) != 0xC ||
1555      Stream.Read(4) != 0xE ||
1556      Stream.Read(4) != 0xD)
1557    return Error("Invalid bitcode signature");
1558
1559  // We expect a number of well-defined blocks, though we don't necessarily
1560  // need to understand them all.
1561  while (!Stream.AtEndOfStream()) {
1562    unsigned Code = Stream.ReadCode();
1563
1564    if (Code != bitc::ENTER_SUBBLOCK)
1565      return Error("Invalid record at top-level");
1566
1567    unsigned BlockID = Stream.ReadSubBlockID();
1568
1569    // We only know the MODULE subblock ID.
1570    switch (BlockID) {
1571    case bitc::BLOCKINFO_BLOCK_ID:
1572      if (Stream.ReadBlockInfoBlock())
1573        return Error("Malformed BlockInfoBlock");
1574      break;
1575    case bitc::MODULE_BLOCK_ID:
1576      // Reject multiple MODULE_BLOCK's in a single bitstream.
1577      if (TheModule)
1578        return Error("Multiple MODULE_BLOCKs in same stream");
1579      TheModule = M;
1580      if (ParseModule())
1581        return true;
1582      break;
1583    default:
1584      if (Stream.SkipBlock())
1585        return Error("Malformed block record");
1586      break;
1587    }
1588  }
1589
1590  return false;
1591}
1592
1593/// ParseMetadataAttachment - Parse metadata attachments.
1594bool BitcodeReader::ParseMetadataAttachment() {
1595  if (Stream.EnterSubBlock(bitc::METADATA_ATTACHMENT_ID))
1596    return Error("Malformed block record");
1597
1598  SmallVector<uint64_t, 64> Record;
1599  while(1) {
1600    unsigned Code = Stream.ReadCode();
1601    if (Code == bitc::END_BLOCK) {
1602      if (Stream.ReadBlockEnd())
1603        return Error("Error at end of PARAMATTR block");
1604      break;
1605    }
1606    if (Code == bitc::DEFINE_ABBREV) {
1607      Stream.ReadAbbrevRecord();
1608      continue;
1609    }
1610    // Read a metadata attachment record.
1611    Record.clear();
1612    switch (Stream.ReadRecord(Code, Record)) {
1613    default:  // Default behavior: ignore.
1614      break;
1615    case bitc::METADATA_ATTACHMENT: {
1616      unsigned RecordLength = Record.size();
1617      if (Record.empty() || (RecordLength - 1) % 2 == 1)
1618        return Error ("Invalid METADATA_ATTACHMENT reader!");
1619      Instruction *Inst = InstructionList[Record[0]];
1620      for (unsigned i = 1; i != RecordLength; i = i+2) {
1621        unsigned Kind = Record[i];
1622        Value *Node = MDValueList.getValueFwdRef(Record[i+1]);
1623        Inst->setMetadata(Kind, cast<MDNode>(Node));
1624      }
1625      break;
1626    }
1627    }
1628  }
1629  return false;
1630}
1631
1632/// ParseFunctionBody - Lazily parse the specified function body block.
1633bool BitcodeReader::ParseFunctionBody(Function *F) {
1634  if (Stream.EnterSubBlock(bitc::FUNCTION_BLOCK_ID))
1635    return Error("Malformed block record");
1636
1637  InstructionList.clear();
1638  unsigned ModuleValueListSize = ValueList.size();
1639
1640  // Add all the function arguments to the value table.
1641  for(Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
1642    ValueList.push_back(I);
1643
1644  unsigned NextValueNo = ValueList.size();
1645  BasicBlock *CurBB = 0;
1646  unsigned CurBBNo = 0;
1647
1648  DebugLoc LastLoc;
1649
1650  // Read all the records.
1651  SmallVector<uint64_t, 64> Record;
1652  while (1) {
1653    unsigned Code = Stream.ReadCode();
1654    if (Code == bitc::END_BLOCK) {
1655      if (Stream.ReadBlockEnd())
1656        return Error("Error at end of function block");
1657      break;
1658    }
1659
1660    if (Code == bitc::ENTER_SUBBLOCK) {
1661      switch (Stream.ReadSubBlockID()) {
1662      default:  // Skip unknown content.
1663        if (Stream.SkipBlock())
1664          return Error("Malformed block record");
1665        break;
1666      case bitc::CONSTANTS_BLOCK_ID:
1667        if (ParseConstants()) return true;
1668        NextValueNo = ValueList.size();
1669        break;
1670      case bitc::VALUE_SYMTAB_BLOCK_ID:
1671        if (ParseValueSymbolTable()) return true;
1672        break;
1673      case bitc::METADATA_ATTACHMENT_ID:
1674        if (ParseMetadataAttachment()) return true;
1675        break;
1676      case bitc::METADATA_BLOCK_ID:
1677        if (ParseMetadata()) return true;
1678        break;
1679      }
1680      continue;
1681    }
1682
1683    if (Code == bitc::DEFINE_ABBREV) {
1684      Stream.ReadAbbrevRecord();
1685      continue;
1686    }
1687
1688    // Read a record.
1689    Record.clear();
1690    Instruction *I = 0;
1691    unsigned BitCode = Stream.ReadRecord(Code, Record);
1692    switch (BitCode) {
1693    default: // Default behavior: reject
1694      return Error("Unknown instruction");
1695    case bitc::FUNC_CODE_DECLAREBLOCKS:     // DECLAREBLOCKS: [nblocks]
1696      if (Record.size() < 1 || Record[0] == 0)
1697        return Error("Invalid DECLAREBLOCKS record");
1698      // Create all the basic blocks for the function.
1699      FunctionBBs.resize(Record[0]);
1700      for (unsigned i = 0, e = FunctionBBs.size(); i != e; ++i)
1701        FunctionBBs[i] = BasicBlock::Create(Context, "", F);
1702      CurBB = FunctionBBs[0];
1703      continue;
1704
1705
1706    case bitc::FUNC_CODE_DEBUG_LOC_AGAIN:  // DEBUG_LOC_AGAIN
1707      // This record indicates that the last instruction is at the same
1708      // location as the previous instruction with a location.
1709      I = 0;
1710
1711      // Get the last instruction emitted.
1712      if (CurBB && !CurBB->empty())
1713        I = &CurBB->back();
1714      else if (CurBBNo && FunctionBBs[CurBBNo-1] &&
1715               !FunctionBBs[CurBBNo-1]->empty())
1716        I = &FunctionBBs[CurBBNo-1]->back();
1717
1718      if (I == 0) return Error("Invalid DEBUG_LOC_AGAIN record");
1719      I->setDebugLoc(LastLoc);
1720      I = 0;
1721      continue;
1722
1723    case bitc::FUNC_CODE_DEBUG_LOC: {      // DEBUG_LOC: [line, col, scope, ia]
1724      I = 0;     // Get the last instruction emitted.
1725      if (CurBB && !CurBB->empty())
1726        I = &CurBB->back();
1727      else if (CurBBNo && FunctionBBs[CurBBNo-1] &&
1728               !FunctionBBs[CurBBNo-1]->empty())
1729        I = &FunctionBBs[CurBBNo-1]->back();
1730      if (I == 0 || Record.size() < 4)
1731        return Error("Invalid FUNC_CODE_DEBUG_LOC record");
1732
1733      unsigned Line = Record[0], Col = Record[1];
1734      unsigned ScopeID = Record[2], IAID = Record[3];
1735
1736      MDNode *Scope = 0, *IA = 0;
1737      if (ScopeID) Scope = cast<MDNode>(MDValueList.getValueFwdRef(ScopeID-1));
1738      if (IAID)    IA = cast<MDNode>(MDValueList.getValueFwdRef(IAID-1));
1739      LastLoc = DebugLoc::get(Line, Col, Scope, IA);
1740      I->setDebugLoc(LastLoc);
1741      I = 0;
1742      continue;
1743    }
1744
1745    case bitc::FUNC_CODE_INST_BINOP: {    // BINOP: [opval, ty, opval, opcode]
1746      unsigned OpNum = 0;
1747      Value *LHS, *RHS;
1748      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
1749          getValue(Record, OpNum, LHS->getType(), RHS) ||
1750          OpNum+1 > Record.size())
1751        return Error("Invalid BINOP record");
1752
1753      int Opc = GetDecodedBinaryOpcode(Record[OpNum++], LHS->getType());
1754      if (Opc == -1) return Error("Invalid BINOP record");
1755      I = BinaryOperator::Create((Instruction::BinaryOps)Opc, LHS, RHS);
1756      InstructionList.push_back(I);
1757      if (OpNum < Record.size()) {
1758        if (Opc == Instruction::Add ||
1759            Opc == Instruction::Sub ||
1760            Opc == Instruction::Mul) {
1761          if (Record[OpNum] & (1 << bitc::OBO_NO_SIGNED_WRAP))
1762            cast<BinaryOperator>(I)->setHasNoSignedWrap(true);
1763          if (Record[OpNum] & (1 << bitc::OBO_NO_UNSIGNED_WRAP))
1764            cast<BinaryOperator>(I)->setHasNoUnsignedWrap(true);
1765        } else if (Opc == Instruction::SDiv) {
1766          if (Record[OpNum] & (1 << bitc::SDIV_EXACT))
1767            cast<BinaryOperator>(I)->setIsExact(true);
1768        }
1769      }
1770      break;
1771    }
1772    case bitc::FUNC_CODE_INST_CAST: {    // CAST: [opval, opty, destty, castopc]
1773      unsigned OpNum = 0;
1774      Value *Op;
1775      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
1776          OpNum+2 != Record.size())
1777        return Error("Invalid CAST record");
1778
1779      const Type *ResTy = getTypeByID(Record[OpNum]);
1780      int Opc = GetDecodedCastOpcode(Record[OpNum+1]);
1781      if (Opc == -1 || ResTy == 0)
1782        return Error("Invalid CAST record");
1783      I = CastInst::Create((Instruction::CastOps)Opc, Op, ResTy);
1784      InstructionList.push_back(I);
1785      break;
1786    }
1787    case bitc::FUNC_CODE_INST_INBOUNDS_GEP:
1788    case bitc::FUNC_CODE_INST_GEP: { // GEP: [n x operands]
1789      unsigned OpNum = 0;
1790      Value *BasePtr;
1791      if (getValueTypePair(Record, OpNum, NextValueNo, BasePtr))
1792        return Error("Invalid GEP record");
1793
1794      SmallVector<Value*, 16> GEPIdx;
1795      while (OpNum != Record.size()) {
1796        Value *Op;
1797        if (getValueTypePair(Record, OpNum, NextValueNo, Op))
1798          return Error("Invalid GEP record");
1799        GEPIdx.push_back(Op);
1800      }
1801
1802      I = GetElementPtrInst::Create(BasePtr, GEPIdx.begin(), GEPIdx.end());
1803      InstructionList.push_back(I);
1804      if (BitCode == bitc::FUNC_CODE_INST_INBOUNDS_GEP)
1805        cast<GetElementPtrInst>(I)->setIsInBounds(true);
1806      break;
1807    }
1808
1809    case bitc::FUNC_CODE_INST_EXTRACTVAL: {
1810                                       // EXTRACTVAL: [opty, opval, n x indices]
1811      unsigned OpNum = 0;
1812      Value *Agg;
1813      if (getValueTypePair(Record, OpNum, NextValueNo, Agg))
1814        return Error("Invalid EXTRACTVAL record");
1815
1816      SmallVector<unsigned, 4> EXTRACTVALIdx;
1817      for (unsigned RecSize = Record.size();
1818           OpNum != RecSize; ++OpNum) {
1819        uint64_t Index = Record[OpNum];
1820        if ((unsigned)Index != Index)
1821          return Error("Invalid EXTRACTVAL index");
1822        EXTRACTVALIdx.push_back((unsigned)Index);
1823      }
1824
1825      I = ExtractValueInst::Create(Agg,
1826                                   EXTRACTVALIdx.begin(), EXTRACTVALIdx.end());
1827      InstructionList.push_back(I);
1828      break;
1829    }
1830
1831    case bitc::FUNC_CODE_INST_INSERTVAL: {
1832                           // INSERTVAL: [opty, opval, opty, opval, n x indices]
1833      unsigned OpNum = 0;
1834      Value *Agg;
1835      if (getValueTypePair(Record, OpNum, NextValueNo, Agg))
1836        return Error("Invalid INSERTVAL record");
1837      Value *Val;
1838      if (getValueTypePair(Record, OpNum, NextValueNo, Val))
1839        return Error("Invalid INSERTVAL record");
1840
1841      SmallVector<unsigned, 4> INSERTVALIdx;
1842      for (unsigned RecSize = Record.size();
1843           OpNum != RecSize; ++OpNum) {
1844        uint64_t Index = Record[OpNum];
1845        if ((unsigned)Index != Index)
1846          return Error("Invalid INSERTVAL index");
1847        INSERTVALIdx.push_back((unsigned)Index);
1848      }
1849
1850      I = InsertValueInst::Create(Agg, Val,
1851                                  INSERTVALIdx.begin(), INSERTVALIdx.end());
1852      InstructionList.push_back(I);
1853      break;
1854    }
1855
1856    case bitc::FUNC_CODE_INST_SELECT: { // SELECT: [opval, ty, opval, opval]
1857      // obsolete form of select
1858      // handles select i1 ... in old bitcode
1859      unsigned OpNum = 0;
1860      Value *TrueVal, *FalseVal, *Cond;
1861      if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
1862          getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
1863          getValue(Record, OpNum, Type::getInt1Ty(Context), Cond))
1864        return Error("Invalid SELECT record");
1865
1866      I = SelectInst::Create(Cond, TrueVal, FalseVal);
1867      InstructionList.push_back(I);
1868      break;
1869    }
1870
1871    case bitc::FUNC_CODE_INST_VSELECT: {// VSELECT: [ty,opval,opval,predty,pred]
1872      // new form of select
1873      // handles select i1 or select [N x i1]
1874      unsigned OpNum = 0;
1875      Value *TrueVal, *FalseVal, *Cond;
1876      if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
1877          getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
1878          getValueTypePair(Record, OpNum, NextValueNo, Cond))
1879        return Error("Invalid SELECT record");
1880
1881      // select condition can be either i1 or [N x i1]
1882      if (const VectorType* vector_type =
1883          dyn_cast<const VectorType>(Cond->getType())) {
1884        // expect <n x i1>
1885        if (vector_type->getElementType() != Type::getInt1Ty(Context))
1886          return Error("Invalid SELECT condition type");
1887      } else {
1888        // expect i1
1889        if (Cond->getType() != Type::getInt1Ty(Context))
1890          return Error("Invalid SELECT condition type");
1891      }
1892
1893      I = SelectInst::Create(Cond, TrueVal, FalseVal);
1894      InstructionList.push_back(I);
1895      break;
1896    }
1897
1898    case bitc::FUNC_CODE_INST_EXTRACTELT: { // EXTRACTELT: [opty, opval, opval]
1899      unsigned OpNum = 0;
1900      Value *Vec, *Idx;
1901      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
1902          getValue(Record, OpNum, Type::getInt32Ty(Context), Idx))
1903        return Error("Invalid EXTRACTELT record");
1904      I = ExtractElementInst::Create(Vec, Idx);
1905      InstructionList.push_back(I);
1906      break;
1907    }
1908
1909    case bitc::FUNC_CODE_INST_INSERTELT: { // INSERTELT: [ty, opval,opval,opval]
1910      unsigned OpNum = 0;
1911      Value *Vec, *Elt, *Idx;
1912      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
1913          getValue(Record, OpNum,
1914                   cast<VectorType>(Vec->getType())->getElementType(), Elt) ||
1915          getValue(Record, OpNum, Type::getInt32Ty(Context), Idx))
1916        return Error("Invalid INSERTELT record");
1917      I = InsertElementInst::Create(Vec, Elt, Idx);
1918      InstructionList.push_back(I);
1919      break;
1920    }
1921
1922    case bitc::FUNC_CODE_INST_SHUFFLEVEC: {// SHUFFLEVEC: [opval,ty,opval,opval]
1923      unsigned OpNum = 0;
1924      Value *Vec1, *Vec2, *Mask;
1925      if (getValueTypePair(Record, OpNum, NextValueNo, Vec1) ||
1926          getValue(Record, OpNum, Vec1->getType(), Vec2))
1927        return Error("Invalid SHUFFLEVEC record");
1928
1929      if (getValueTypePair(Record, OpNum, NextValueNo, Mask))
1930        return Error("Invalid SHUFFLEVEC record");
1931      I = new ShuffleVectorInst(Vec1, Vec2, Mask);
1932      InstructionList.push_back(I);
1933      break;
1934    }
1935
1936    case bitc::FUNC_CODE_INST_CMP:   // CMP: [opty, opval, opval, pred]
1937      // Old form of ICmp/FCmp returning bool
1938      // Existed to differentiate between icmp/fcmp and vicmp/vfcmp which were
1939      // both legal on vectors but had different behaviour.
1940    case bitc::FUNC_CODE_INST_CMP2: { // CMP2: [opty, opval, opval, pred]
1941      // FCmp/ICmp returning bool or vector of bool
1942
1943      unsigned OpNum = 0;
1944      Value *LHS, *RHS;
1945      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
1946          getValue(Record, OpNum, LHS->getType(), RHS) ||
1947          OpNum+1 != Record.size())
1948        return Error("Invalid CMP record");
1949
1950      if (LHS->getType()->isFPOrFPVectorTy())
1951        I = new FCmpInst((FCmpInst::Predicate)Record[OpNum], LHS, RHS);
1952      else
1953        I = new ICmpInst((ICmpInst::Predicate)Record[OpNum], LHS, RHS);
1954      InstructionList.push_back(I);
1955      break;
1956    }
1957
1958    case bitc::FUNC_CODE_INST_GETRESULT: { // GETRESULT: [ty, val, n]
1959      if (Record.size() != 2)
1960        return Error("Invalid GETRESULT record");
1961      unsigned OpNum = 0;
1962      Value *Op;
1963      getValueTypePair(Record, OpNum, NextValueNo, Op);
1964      unsigned Index = Record[1];
1965      I = ExtractValueInst::Create(Op, Index);
1966      InstructionList.push_back(I);
1967      break;
1968    }
1969
1970    case bitc::FUNC_CODE_INST_RET: // RET: [opty,opval<optional>]
1971      {
1972        unsigned Size = Record.size();
1973        if (Size == 0) {
1974          I = ReturnInst::Create(Context);
1975          InstructionList.push_back(I);
1976          break;
1977        }
1978
1979        unsigned OpNum = 0;
1980        SmallVector<Value *,4> Vs;
1981        do {
1982          Value *Op = NULL;
1983          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
1984            return Error("Invalid RET record");
1985          Vs.push_back(Op);
1986        } while(OpNum != Record.size());
1987
1988        const Type *ReturnType = F->getReturnType();
1989        if (Vs.size() > 1 ||
1990            (ReturnType->isStructTy() &&
1991             (Vs.empty() || Vs[0]->getType() != ReturnType))) {
1992          Value *RV = UndefValue::get(ReturnType);
1993          for (unsigned i = 0, e = Vs.size(); i != e; ++i) {
1994            I = InsertValueInst::Create(RV, Vs[i], i, "mrv");
1995            InstructionList.push_back(I);
1996            CurBB->getInstList().push_back(I);
1997            ValueList.AssignValue(I, NextValueNo++);
1998            RV = I;
1999          }
2000          I = ReturnInst::Create(Context, RV);
2001          InstructionList.push_back(I);
2002          break;
2003        }
2004
2005        I = ReturnInst::Create(Context, Vs[0]);
2006        InstructionList.push_back(I);
2007        break;
2008      }
2009    case bitc::FUNC_CODE_INST_BR: { // BR: [bb#, bb#, opval] or [bb#]
2010      if (Record.size() != 1 && Record.size() != 3)
2011        return Error("Invalid BR record");
2012      BasicBlock *TrueDest = getBasicBlock(Record[0]);
2013      if (TrueDest == 0)
2014        return Error("Invalid BR record");
2015
2016      if (Record.size() == 1) {
2017        I = BranchInst::Create(TrueDest);
2018        InstructionList.push_back(I);
2019      }
2020      else {
2021        BasicBlock *FalseDest = getBasicBlock(Record[1]);
2022        Value *Cond = getFnValueByID(Record[2], Type::getInt1Ty(Context));
2023        if (FalseDest == 0 || Cond == 0)
2024          return Error("Invalid BR record");
2025        I = BranchInst::Create(TrueDest, FalseDest, Cond);
2026        InstructionList.push_back(I);
2027      }
2028      break;
2029    }
2030    case bitc::FUNC_CODE_INST_SWITCH: { // SWITCH: [opty, op0, op1, ...]
2031      if (Record.size() < 3 || (Record.size() & 1) == 0)
2032        return Error("Invalid SWITCH record");
2033      const Type *OpTy = getTypeByID(Record[0]);
2034      Value *Cond = getFnValueByID(Record[1], OpTy);
2035      BasicBlock *Default = getBasicBlock(Record[2]);
2036      if (OpTy == 0 || Cond == 0 || Default == 0)
2037        return Error("Invalid SWITCH record");
2038      unsigned NumCases = (Record.size()-3)/2;
2039      SwitchInst *SI = SwitchInst::Create(Cond, Default, NumCases);
2040      InstructionList.push_back(SI);
2041      for (unsigned i = 0, e = NumCases; i != e; ++i) {
2042        ConstantInt *CaseVal =
2043          dyn_cast_or_null<ConstantInt>(getFnValueByID(Record[3+i*2], OpTy));
2044        BasicBlock *DestBB = getBasicBlock(Record[1+3+i*2]);
2045        if (CaseVal == 0 || DestBB == 0) {
2046          delete SI;
2047          return Error("Invalid SWITCH record!");
2048        }
2049        SI->addCase(CaseVal, DestBB);
2050      }
2051      I = SI;
2052      break;
2053    }
2054    case bitc::FUNC_CODE_INST_INDIRECTBR: { // INDIRECTBR: [opty, op0, op1, ...]
2055      if (Record.size() < 2)
2056        return Error("Invalid INDIRECTBR record");
2057      const Type *OpTy = getTypeByID(Record[0]);
2058      Value *Address = getFnValueByID(Record[1], OpTy);
2059      if (OpTy == 0 || Address == 0)
2060        return Error("Invalid INDIRECTBR record");
2061      unsigned NumDests = Record.size()-2;
2062      IndirectBrInst *IBI = IndirectBrInst::Create(Address, NumDests);
2063      InstructionList.push_back(IBI);
2064      for (unsigned i = 0, e = NumDests; i != e; ++i) {
2065        if (BasicBlock *DestBB = getBasicBlock(Record[2+i])) {
2066          IBI->addDestination(DestBB);
2067        } else {
2068          delete IBI;
2069          return Error("Invalid INDIRECTBR record!");
2070        }
2071      }
2072      I = IBI;
2073      break;
2074    }
2075
2076    case bitc::FUNC_CODE_INST_INVOKE: {
2077      // INVOKE: [attrs, cc, normBB, unwindBB, fnty, op0,op1,op2, ...]
2078      if (Record.size() < 4) return Error("Invalid INVOKE record");
2079      AttrListPtr PAL = getAttributes(Record[0]);
2080      unsigned CCInfo = Record[1];
2081      BasicBlock *NormalBB = getBasicBlock(Record[2]);
2082      BasicBlock *UnwindBB = getBasicBlock(Record[3]);
2083
2084      unsigned OpNum = 4;
2085      Value *Callee;
2086      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
2087        return Error("Invalid INVOKE record");
2088
2089      const PointerType *CalleeTy = dyn_cast<PointerType>(Callee->getType());
2090      const FunctionType *FTy = !CalleeTy ? 0 :
2091        dyn_cast<FunctionType>(CalleeTy->getElementType());
2092
2093      // Check that the right number of fixed parameters are here.
2094      if (FTy == 0 || NormalBB == 0 || UnwindBB == 0 ||
2095          Record.size() < OpNum+FTy->getNumParams())
2096        return Error("Invalid INVOKE record");
2097
2098      SmallVector<Value*, 16> Ops;
2099      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
2100        Ops.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
2101        if (Ops.back() == 0) return Error("Invalid INVOKE record");
2102      }
2103
2104      if (!FTy->isVarArg()) {
2105        if (Record.size() != OpNum)
2106          return Error("Invalid INVOKE record");
2107      } else {
2108        // Read type/value pairs for varargs params.
2109        while (OpNum != Record.size()) {
2110          Value *Op;
2111          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2112            return Error("Invalid INVOKE record");
2113          Ops.push_back(Op);
2114        }
2115      }
2116
2117      I = InvokeInst::Create(Callee, NormalBB, UnwindBB,
2118                             Ops.begin(), Ops.end());
2119      InstructionList.push_back(I);
2120      cast<InvokeInst>(I)->setCallingConv(
2121        static_cast<CallingConv::ID>(CCInfo));
2122      cast<InvokeInst>(I)->setAttributes(PAL);
2123      break;
2124    }
2125    case bitc::FUNC_CODE_INST_UNWIND: // UNWIND
2126      I = new UnwindInst(Context);
2127      InstructionList.push_back(I);
2128      break;
2129    case bitc::FUNC_CODE_INST_UNREACHABLE: // UNREACHABLE
2130      I = new UnreachableInst(Context);
2131      InstructionList.push_back(I);
2132      break;
2133    case bitc::FUNC_CODE_INST_PHI: { // PHI: [ty, val0,bb0, ...]
2134      if (Record.size() < 1 || ((Record.size()-1)&1))
2135        return Error("Invalid PHI record");
2136      const Type *Ty = getTypeByID(Record[0]);
2137      if (!Ty) return Error("Invalid PHI record");
2138
2139      PHINode *PN = PHINode::Create(Ty);
2140      InstructionList.push_back(PN);
2141      PN->reserveOperandSpace((Record.size()-1)/2);
2142
2143      for (unsigned i = 0, e = Record.size()-1; i != e; i += 2) {
2144        Value *V = getFnValueByID(Record[1+i], Ty);
2145        BasicBlock *BB = getBasicBlock(Record[2+i]);
2146        if (!V || !BB) return Error("Invalid PHI record");
2147        PN->addIncoming(V, BB);
2148      }
2149      I = PN;
2150      break;
2151    }
2152
2153    case bitc::FUNC_CODE_INST_MALLOC: { // MALLOC: [instty, op, align]
2154      // Autoupgrade malloc instruction to malloc call.
2155      // FIXME: Remove in LLVM 3.0.
2156      if (Record.size() < 3)
2157        return Error("Invalid MALLOC record");
2158      const PointerType *Ty =
2159        dyn_cast_or_null<PointerType>(getTypeByID(Record[0]));
2160      Value *Size = getFnValueByID(Record[1], Type::getInt32Ty(Context));
2161      if (!Ty || !Size) return Error("Invalid MALLOC record");
2162      if (!CurBB) return Error("Invalid malloc instruction with no BB");
2163      const Type *Int32Ty = IntegerType::getInt32Ty(CurBB->getContext());
2164      Constant *AllocSize = ConstantExpr::getSizeOf(Ty->getElementType());
2165      AllocSize = ConstantExpr::getTruncOrBitCast(AllocSize, Int32Ty);
2166      I = CallInst::CreateMalloc(CurBB, Int32Ty, Ty->getElementType(),
2167                                 AllocSize, Size, NULL);
2168      InstructionList.push_back(I);
2169      break;
2170    }
2171    case bitc::FUNC_CODE_INST_FREE: { // FREE: [op, opty]
2172      unsigned OpNum = 0;
2173      Value *Op;
2174      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
2175          OpNum != Record.size())
2176        return Error("Invalid FREE record");
2177      if (!CurBB) return Error("Invalid free instruction with no BB");
2178      I = CallInst::CreateFree(Op, CurBB);
2179      InstructionList.push_back(I);
2180      break;
2181    }
2182    case bitc::FUNC_CODE_INST_ALLOCA: { // ALLOCA: [instty, opty, op, align]
2183      // For backward compatibility, tolerate a lack of an opty, and use i32.
2184      // LLVM 3.0: Remove this.
2185      if (Record.size() < 3 || Record.size() > 4)
2186        return Error("Invalid ALLOCA record");
2187      unsigned OpNum = 0;
2188      const PointerType *Ty =
2189        dyn_cast_or_null<PointerType>(getTypeByID(Record[OpNum++]));
2190      const Type *OpTy = Record.size() == 4 ? getTypeByID(Record[OpNum++]) :
2191                                              Type::getInt32Ty(Context);
2192      Value *Size = getFnValueByID(Record[OpNum++], OpTy);
2193      unsigned Align = Record[OpNum++];
2194      if (!Ty || !Size) return Error("Invalid ALLOCA record");
2195      I = new AllocaInst(Ty->getElementType(), Size, (1 << Align) >> 1);
2196      InstructionList.push_back(I);
2197      break;
2198    }
2199    case bitc::FUNC_CODE_INST_LOAD: { // LOAD: [opty, op, align, vol]
2200      unsigned OpNum = 0;
2201      Value *Op;
2202      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
2203          OpNum+2 != Record.size())
2204        return Error("Invalid LOAD record");
2205
2206      I = new LoadInst(Op, "", Record[OpNum+1], (1 << Record[OpNum]) >> 1);
2207      InstructionList.push_back(I);
2208      break;
2209    }
2210    case bitc::FUNC_CODE_INST_STORE2: { // STORE2:[ptrty, ptr, val, align, vol]
2211      unsigned OpNum = 0;
2212      Value *Val, *Ptr;
2213      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
2214          getValue(Record, OpNum,
2215                    cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
2216          OpNum+2 != Record.size())
2217        return Error("Invalid STORE record");
2218
2219      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1);
2220      InstructionList.push_back(I);
2221      break;
2222    }
2223    case bitc::FUNC_CODE_INST_STORE: { // STORE:[val, valty, ptr, align, vol]
2224      // FIXME: Legacy form of store instruction. Should be removed in LLVM 3.0.
2225      unsigned OpNum = 0;
2226      Value *Val, *Ptr;
2227      if (getValueTypePair(Record, OpNum, NextValueNo, Val) ||
2228          getValue(Record, OpNum,
2229                   PointerType::getUnqual(Val->getType()), Ptr)||
2230          OpNum+2 != Record.size())
2231        return Error("Invalid STORE record");
2232
2233      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1);
2234      InstructionList.push_back(I);
2235      break;
2236    }
2237    case bitc::FUNC_CODE_INST_CALL: {
2238      // CALL: [paramattrs, cc, fnty, fnid, arg0, arg1...]
2239      if (Record.size() < 3)
2240        return Error("Invalid CALL record");
2241
2242      AttrListPtr PAL = getAttributes(Record[0]);
2243      unsigned CCInfo = Record[1];
2244
2245      unsigned OpNum = 2;
2246      Value *Callee;
2247      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
2248        return Error("Invalid CALL record");
2249
2250      const PointerType *OpTy = dyn_cast<PointerType>(Callee->getType());
2251      const FunctionType *FTy = 0;
2252      if (OpTy) FTy = dyn_cast<FunctionType>(OpTy->getElementType());
2253      if (!FTy || Record.size() < FTy->getNumParams()+OpNum)
2254        return Error("Invalid CALL record");
2255
2256      SmallVector<Value*, 16> Args;
2257      // Read the fixed params.
2258      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
2259        if (FTy->getParamType(i)->getTypeID()==Type::LabelTyID)
2260          Args.push_back(getBasicBlock(Record[OpNum]));
2261        else
2262          Args.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
2263        if (Args.back() == 0) return Error("Invalid CALL record");
2264      }
2265
2266      // Read type/value pairs for varargs params.
2267      if (!FTy->isVarArg()) {
2268        if (OpNum != Record.size())
2269          return Error("Invalid CALL record");
2270      } else {
2271        while (OpNum != Record.size()) {
2272          Value *Op;
2273          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2274            return Error("Invalid CALL record");
2275          Args.push_back(Op);
2276        }
2277      }
2278
2279      I = CallInst::Create(Callee, Args.begin(), Args.end());
2280      InstructionList.push_back(I);
2281      cast<CallInst>(I)->setCallingConv(
2282        static_cast<CallingConv::ID>(CCInfo>>1));
2283      cast<CallInst>(I)->setTailCall(CCInfo & 1);
2284      cast<CallInst>(I)->setAttributes(PAL);
2285      break;
2286    }
2287    case bitc::FUNC_CODE_INST_VAARG: { // VAARG: [valistty, valist, instty]
2288      if (Record.size() < 3)
2289        return Error("Invalid VAARG record");
2290      const Type *OpTy = getTypeByID(Record[0]);
2291      Value *Op = getFnValueByID(Record[1], OpTy);
2292      const Type *ResTy = getTypeByID(Record[2]);
2293      if (!OpTy || !Op || !ResTy)
2294        return Error("Invalid VAARG record");
2295      I = new VAArgInst(Op, ResTy);
2296      InstructionList.push_back(I);
2297      break;
2298    }
2299    }
2300
2301    // Add instruction to end of current BB.  If there is no current BB, reject
2302    // this file.
2303    if (CurBB == 0) {
2304      delete I;
2305      return Error("Invalid instruction with no BB");
2306    }
2307    CurBB->getInstList().push_back(I);
2308
2309    // If this was a terminator instruction, move to the next block.
2310    if (isa<TerminatorInst>(I)) {
2311      ++CurBBNo;
2312      CurBB = CurBBNo < FunctionBBs.size() ? FunctionBBs[CurBBNo] : 0;
2313    }
2314
2315    // Non-void values get registered in the value table for future use.
2316    if (I && !I->getType()->isVoidTy())
2317      ValueList.AssignValue(I, NextValueNo++);
2318  }
2319
2320  // Check the function list for unresolved values.
2321  if (Argument *A = dyn_cast<Argument>(ValueList.back())) {
2322    if (A->getParent() == 0) {
2323      // We found at least one unresolved value.  Nuke them all to avoid leaks.
2324      for (unsigned i = ModuleValueListSize, e = ValueList.size(); i != e; ++i){
2325        if ((A = dyn_cast<Argument>(ValueList.back())) && A->getParent() == 0) {
2326          A->replaceAllUsesWith(UndefValue::get(A->getType()));
2327          delete A;
2328        }
2329      }
2330      return Error("Never resolved value found in function!");
2331    }
2332  }
2333
2334  // See if anything took the address of blocks in this function.  If so,
2335  // resolve them now.
2336  DenseMap<Function*, std::vector<BlockAddrRefTy> >::iterator BAFRI =
2337    BlockAddrFwdRefs.find(F);
2338  if (BAFRI != BlockAddrFwdRefs.end()) {
2339    std::vector<BlockAddrRefTy> &RefList = BAFRI->second;
2340    for (unsigned i = 0, e = RefList.size(); i != e; ++i) {
2341      unsigned BlockIdx = RefList[i].first;
2342      if (BlockIdx >= FunctionBBs.size())
2343        return Error("Invalid blockaddress block #");
2344
2345      GlobalVariable *FwdRef = RefList[i].second;
2346      FwdRef->replaceAllUsesWith(BlockAddress::get(F, FunctionBBs[BlockIdx]));
2347      FwdRef->eraseFromParent();
2348    }
2349
2350    BlockAddrFwdRefs.erase(BAFRI);
2351  }
2352
2353  // Trim the value list down to the size it was before we parsed this function.
2354  ValueList.shrinkTo(ModuleValueListSize);
2355  std::vector<BasicBlock*>().swap(FunctionBBs);
2356
2357  return false;
2358}
2359
2360//===----------------------------------------------------------------------===//
2361// GVMaterializer implementation
2362//===----------------------------------------------------------------------===//
2363
2364
2365bool BitcodeReader::isMaterializable(const GlobalValue *GV) const {
2366  if (const Function *F = dyn_cast<Function>(GV)) {
2367    return F->isDeclaration() &&
2368      DeferredFunctionInfo.count(const_cast<Function*>(F));
2369  }
2370  return false;
2371}
2372
2373bool BitcodeReader::Materialize(GlobalValue *GV, std::string *ErrInfo) {
2374  Function *F = dyn_cast<Function>(GV);
2375  // If it's not a function or is already material, ignore the request.
2376  if (!F || !F->isMaterializable()) return false;
2377
2378  DenseMap<Function*, uint64_t>::iterator DFII = DeferredFunctionInfo.find(F);
2379  assert(DFII != DeferredFunctionInfo.end() && "Deferred function not found!");
2380
2381  // Move the bit stream to the saved position of the deferred function body.
2382  Stream.JumpToBit(DFII->second);
2383
2384  if (ParseFunctionBody(F)) {
2385    if (ErrInfo) *ErrInfo = ErrorString;
2386    return true;
2387  }
2388
2389  // Upgrade any old intrinsic calls in the function.
2390  for (UpgradedIntrinsicMap::iterator I = UpgradedIntrinsics.begin(),
2391       E = UpgradedIntrinsics.end(); I != E; ++I) {
2392    if (I->first != I->second) {
2393      for (Value::use_iterator UI = I->first->use_begin(),
2394           UE = I->first->use_end(); UI != UE; ) {
2395        if (CallInst* CI = dyn_cast<CallInst>(*UI++))
2396          UpgradeIntrinsicCall(CI, I->second);
2397      }
2398    }
2399  }
2400
2401  return false;
2402}
2403
2404bool BitcodeReader::isDematerializable(const GlobalValue *GV) const {
2405  const Function *F = dyn_cast<Function>(GV);
2406  if (!F || F->isDeclaration())
2407    return false;
2408  return DeferredFunctionInfo.count(const_cast<Function*>(F));
2409}
2410
2411void BitcodeReader::Dematerialize(GlobalValue *GV) {
2412  Function *F = dyn_cast<Function>(GV);
2413  // If this function isn't dematerializable, this is a noop.
2414  if (!F || !isDematerializable(F))
2415    return;
2416
2417  assert(DeferredFunctionInfo.count(F) && "No info to read function later?");
2418
2419  // Just forget the function body, we can remat it later.
2420  F->deleteBody();
2421}
2422
2423
2424bool BitcodeReader::MaterializeModule(Module *M, std::string *ErrInfo) {
2425  assert(M == TheModule &&
2426         "Can only Materialize the Module this BitcodeReader is attached to.");
2427  // Iterate over the module, deserializing any functions that are still on
2428  // disk.
2429  for (Module::iterator F = TheModule->begin(), E = TheModule->end();
2430       F != E; ++F)
2431    if (F->isMaterializable() &&
2432        Materialize(F, ErrInfo))
2433      return true;
2434
2435  // Upgrade any intrinsic calls that slipped through (should not happen!) and
2436  // delete the old functions to clean up. We can't do this unless the entire
2437  // module is materialized because there could always be another function body
2438  // with calls to the old function.
2439  for (std::vector<std::pair<Function*, Function*> >::iterator I =
2440       UpgradedIntrinsics.begin(), E = UpgradedIntrinsics.end(); I != E; ++I) {
2441    if (I->first != I->second) {
2442      for (Value::use_iterator UI = I->first->use_begin(),
2443           UE = I->first->use_end(); UI != UE; ) {
2444        if (CallInst* CI = dyn_cast<CallInst>(*UI++))
2445          UpgradeIntrinsicCall(CI, I->second);
2446      }
2447      if (!I->first->use_empty())
2448        I->first->replaceAllUsesWith(I->second);
2449      I->first->eraseFromParent();
2450    }
2451  }
2452  std::vector<std::pair<Function*, Function*> >().swap(UpgradedIntrinsics);
2453
2454  // Check debug info intrinsics.
2455  CheckDebugInfoIntrinsics(TheModule);
2456
2457  return false;
2458}
2459
2460
2461//===----------------------------------------------------------------------===//
2462// External interface
2463//===----------------------------------------------------------------------===//
2464
2465/// getLazyBitcodeModule - lazy function-at-a-time loading from a file.
2466///
2467Module *llvm::getLazyBitcodeModule(MemoryBuffer *Buffer,
2468                                   LLVMContext& Context,
2469                                   std::string *ErrMsg) {
2470  Module *M = new Module(Buffer->getBufferIdentifier(), Context);
2471  BitcodeReader *R = new BitcodeReader(Buffer, Context);
2472  M->setMaterializer(R);
2473  if (R->ParseBitcodeInto(M)) {
2474    if (ErrMsg)
2475      *ErrMsg = R->getErrorString();
2476
2477    delete M;  // Also deletes R.
2478    return 0;
2479  }
2480  // Have the BitcodeReader dtor delete 'Buffer'.
2481  R->setBufferOwned(true);
2482  return M;
2483}
2484
2485/// ParseBitcodeFile - Read the specified bitcode file, returning the module.
2486/// If an error occurs, return null and fill in *ErrMsg if non-null.
2487Module *llvm::ParseBitcodeFile(MemoryBuffer *Buffer, LLVMContext& Context,
2488                               std::string *ErrMsg){
2489  Module *M = getLazyBitcodeModule(Buffer, Context, ErrMsg);
2490  if (!M) return 0;
2491
2492  // Don't let the BitcodeReader dtor delete 'Buffer', regardless of whether
2493  // there was an error.
2494  static_cast<BitcodeReader*>(M->getMaterializer())->setBufferOwned(false);
2495
2496  // Read in the entire module, and destroy the BitcodeReader.
2497  if (M->MaterializeAllPermanently(ErrMsg)) {
2498    delete M;
2499    return NULL;
2500  }
2501  return M;
2502}
2503