BitcodeReader.cpp revision 1cce5bf8ef9ee3dc157ae5d8778f84a7a0d1d8b9 
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/DataStream.h"
26#include "llvm/Support/MathExtras.h"
27#include "llvm/Support/MemoryBuffer.h"
28#include "llvm/OperandTraits.h"
29using namespace llvm;
30
31enum {
32  SWITCH_INST_MAGIC = 0x4B5 // May 2012 => 1205 => Hex
33};
34
35void BitcodeReader::materializeForwardReferencedFunctions() {
36  while (!BlockAddrFwdRefs.empty()) {
37    Function *F = BlockAddrFwdRefs.begin()->first;
38    F->Materialize();
39  }
40}
41
42void BitcodeReader::FreeState() {
43  if (BufferOwned)
44    delete Buffer;
45  Buffer = 0;
46  std::vector<Type*>().swap(TypeList);
47  ValueList.clear();
48  MDValueList.clear();
49
50  std::vector<AttrListPtr>().swap(MAttributes);
51  std::vector<BasicBlock*>().swap(FunctionBBs);
52  std::vector<Function*>().swap(FunctionsWithBodies);
53  DeferredFunctionInfo.clear();
54  MDKindMap.clear();
55}
56
57//===----------------------------------------------------------------------===//
58//  Helper functions to implement forward reference resolution, etc.
59//===----------------------------------------------------------------------===//
60
61/// ConvertToString - Convert a string from a record into an std::string, return
62/// true on failure.
63template<typename StrTy>
64static bool ConvertToString(SmallVector<uint64_t, 64> &Record, unsigned Idx,
65                            StrTy &Result) {
66  if (Idx > Record.size())
67    return true;
68
69  for (unsigned i = Idx, e = Record.size(); i != e; ++i)
70    Result += (char)Record[i];
71  return false;
72}
73
74static GlobalValue::LinkageTypes GetDecodedLinkage(unsigned Val) {
75  switch (Val) {
76  default: // Map unknown/new linkages to external
77  case 0:  return GlobalValue::ExternalLinkage;
78  case 1:  return GlobalValue::WeakAnyLinkage;
79  case 2:  return GlobalValue::AppendingLinkage;
80  case 3:  return GlobalValue::InternalLinkage;
81  case 4:  return GlobalValue::LinkOnceAnyLinkage;
82  case 5:  return GlobalValue::DLLImportLinkage;
83  case 6:  return GlobalValue::DLLExportLinkage;
84  case 7:  return GlobalValue::ExternalWeakLinkage;
85  case 8:  return GlobalValue::CommonLinkage;
86  case 9:  return GlobalValue::PrivateLinkage;
87  case 10: return GlobalValue::WeakODRLinkage;
88  case 11: return GlobalValue::LinkOnceODRLinkage;
89  case 12: return GlobalValue::AvailableExternallyLinkage;
90  case 13: return GlobalValue::LinkerPrivateLinkage;
91  case 14: return GlobalValue::LinkerPrivateWeakLinkage;
92  case 15: return GlobalValue::LinkerPrivateWeakDefAutoLinkage;
93  }
94}
95
96static GlobalValue::VisibilityTypes GetDecodedVisibility(unsigned Val) {
97  switch (Val) {
98  default: // Map unknown visibilities to default.
99  case 0: return GlobalValue::DefaultVisibility;
100  case 1: return GlobalValue::HiddenVisibility;
101  case 2: return GlobalValue::ProtectedVisibility;
102  }
103}
104
105static int GetDecodedCastOpcode(unsigned Val) {
106  switch (Val) {
107  default: return -1;
108  case bitc::CAST_TRUNC   : return Instruction::Trunc;
109  case bitc::CAST_ZEXT    : return Instruction::ZExt;
110  case bitc::CAST_SEXT    : return Instruction::SExt;
111  case bitc::CAST_FPTOUI  : return Instruction::FPToUI;
112  case bitc::CAST_FPTOSI  : return Instruction::FPToSI;
113  case bitc::CAST_UITOFP  : return Instruction::UIToFP;
114  case bitc::CAST_SITOFP  : return Instruction::SIToFP;
115  case bitc::CAST_FPTRUNC : return Instruction::FPTrunc;
116  case bitc::CAST_FPEXT   : return Instruction::FPExt;
117  case bitc::CAST_PTRTOINT: return Instruction::PtrToInt;
118  case bitc::CAST_INTTOPTR: return Instruction::IntToPtr;
119  case bitc::CAST_BITCAST : return Instruction::BitCast;
120  }
121}
122static int GetDecodedBinaryOpcode(unsigned Val, Type *Ty) {
123  switch (Val) {
124  default: return -1;
125  case bitc::BINOP_ADD:
126    return Ty->isFPOrFPVectorTy() ? Instruction::FAdd : Instruction::Add;
127  case bitc::BINOP_SUB:
128    return Ty->isFPOrFPVectorTy() ? Instruction::FSub : Instruction::Sub;
129  case bitc::BINOP_MUL:
130    return Ty->isFPOrFPVectorTy() ? Instruction::FMul : Instruction::Mul;
131  case bitc::BINOP_UDIV: return Instruction::UDiv;
132  case bitc::BINOP_SDIV:
133    return Ty->isFPOrFPVectorTy() ? Instruction::FDiv : Instruction::SDiv;
134  case bitc::BINOP_UREM: return Instruction::URem;
135  case bitc::BINOP_SREM:
136    return Ty->isFPOrFPVectorTy() ? Instruction::FRem : Instruction::SRem;
137  case bitc::BINOP_SHL:  return Instruction::Shl;
138  case bitc::BINOP_LSHR: return Instruction::LShr;
139  case bitc::BINOP_ASHR: return Instruction::AShr;
140  case bitc::BINOP_AND:  return Instruction::And;
141  case bitc::BINOP_OR:   return Instruction::Or;
142  case bitc::BINOP_XOR:  return Instruction::Xor;
143  }
144}
145
146static AtomicRMWInst::BinOp GetDecodedRMWOperation(unsigned Val) {
147  switch (Val) {
148  default: return AtomicRMWInst::BAD_BINOP;
149  case bitc::RMW_XCHG: return AtomicRMWInst::Xchg;
150  case bitc::RMW_ADD: return AtomicRMWInst::Add;
151  case bitc::RMW_SUB: return AtomicRMWInst::Sub;
152  case bitc::RMW_AND: return AtomicRMWInst::And;
153  case bitc::RMW_NAND: return AtomicRMWInst::Nand;
154  case bitc::RMW_OR: return AtomicRMWInst::Or;
155  case bitc::RMW_XOR: return AtomicRMWInst::Xor;
156  case bitc::RMW_MAX: return AtomicRMWInst::Max;
157  case bitc::RMW_MIN: return AtomicRMWInst::Min;
158  case bitc::RMW_UMAX: return AtomicRMWInst::UMax;
159  case bitc::RMW_UMIN: return AtomicRMWInst::UMin;
160  }
161}
162
163static AtomicOrdering GetDecodedOrdering(unsigned Val) {
164  switch (Val) {
165  case bitc::ORDERING_NOTATOMIC: return NotAtomic;
166  case bitc::ORDERING_UNORDERED: return Unordered;
167  case bitc::ORDERING_MONOTONIC: return Monotonic;
168  case bitc::ORDERING_ACQUIRE: return Acquire;
169  case bitc::ORDERING_RELEASE: return Release;
170  case bitc::ORDERING_ACQREL: return AcquireRelease;
171  default: // Map unknown orderings to sequentially-consistent.
172  case bitc::ORDERING_SEQCST: return SequentiallyConsistent;
173  }
174}
175
176static SynchronizationScope GetDecodedSynchScope(unsigned Val) {
177  switch (Val) {
178  case bitc::SYNCHSCOPE_SINGLETHREAD: return SingleThread;
179  default: // Map unknown scopes to cross-thread.
180  case bitc::SYNCHSCOPE_CROSSTHREAD: return CrossThread;
181  }
182}
183
184namespace llvm {
185namespace {
186  /// @brief A class for maintaining the slot number definition
187  /// as a placeholder for the actual definition for forward constants defs.
188  class ConstantPlaceHolder : public ConstantExpr {
189    void operator=(const ConstantPlaceHolder &); // DO NOT IMPLEMENT
190  public:
191    // allocate space for exactly one operand
192    void *operator new(size_t s) {
193      return User::operator new(s, 1);
194    }
195    explicit ConstantPlaceHolder(Type *Ty, LLVMContext& Context)
196      : ConstantExpr(Ty, Instruction::UserOp1, &Op<0>(), 1) {
197      Op<0>() = UndefValue::get(Type::getInt32Ty(Context));
198    }
199
200    /// @brief Methods to support type inquiry through isa, cast, and dyn_cast.
201    //static inline bool classof(const ConstantPlaceHolder *) { return true; }
202    static bool classof(const Value *V) {
203      return isa<ConstantExpr>(V) &&
204             cast<ConstantExpr>(V)->getOpcode() == Instruction::UserOp1;
205    }
206
207
208    /// Provide fast operand accessors
209    //DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
210  };
211}
212
213// FIXME: can we inherit this from ConstantExpr?
214template <>
215struct OperandTraits<ConstantPlaceHolder> :
216  public FixedNumOperandTraits<ConstantPlaceHolder, 1> {
217};
218}
219
220
221void BitcodeReaderValueList::AssignValue(Value *V, unsigned Idx) {
222  if (Idx == size()) {
223    push_back(V);
224    return;
225  }
226
227  if (Idx >= size())
228    resize(Idx+1);
229
230  WeakVH &OldV = ValuePtrs[Idx];
231  if (OldV == 0) {
232    OldV = V;
233    return;
234  }
235
236  // Handle constants and non-constants (e.g. instrs) differently for
237  // efficiency.
238  if (Constant *PHC = dyn_cast<Constant>(&*OldV)) {
239    ResolveConstants.push_back(std::make_pair(PHC, Idx));
240    OldV = V;
241  } else {
242    // If there was a forward reference to this value, replace it.
243    Value *PrevVal = OldV;
244    OldV->replaceAllUsesWith(V);
245    delete PrevVal;
246  }
247}
248
249
250Constant *BitcodeReaderValueList::getConstantFwdRef(unsigned Idx,
251                                                    Type *Ty) {
252  if (Idx >= size())
253    resize(Idx + 1);
254
255  if (Value *V = ValuePtrs[Idx]) {
256    assert(Ty == V->getType() && "Type mismatch in constant table!");
257    return cast<Constant>(V);
258  }
259
260  // Create and return a placeholder, which will later be RAUW'd.
261  Constant *C = new ConstantPlaceHolder(Ty, Context);
262  ValuePtrs[Idx] = C;
263  return C;
264}
265
266Value *BitcodeReaderValueList::getValueFwdRef(unsigned Idx, Type *Ty) {
267  if (Idx >= size())
268    resize(Idx + 1);
269
270  if (Value *V = ValuePtrs[Idx]) {
271    assert((Ty == 0 || Ty == V->getType()) && "Type mismatch in value table!");
272    return V;
273  }
274
275  // No type specified, must be invalid reference.
276  if (Ty == 0) return 0;
277
278  // Create and return a placeholder, which will later be RAUW'd.
279  Value *V = new Argument(Ty);
280  ValuePtrs[Idx] = V;
281  return V;
282}
283
284/// ResolveConstantForwardRefs - Once all constants are read, this method bulk
285/// resolves any forward references.  The idea behind this is that we sometimes
286/// get constants (such as large arrays) which reference *many* forward ref
287/// constants.  Replacing each of these causes a lot of thrashing when
288/// building/reuniquing the constant.  Instead of doing this, we look at all the
289/// uses and rewrite all the place holders at once for any constant that uses
290/// a placeholder.
291void BitcodeReaderValueList::ResolveConstantForwardRefs() {
292  // Sort the values by-pointer so that they are efficient to look up with a
293  // binary search.
294  std::sort(ResolveConstants.begin(), ResolveConstants.end());
295
296  SmallVector<Constant*, 64> NewOps;
297
298  while (!ResolveConstants.empty()) {
299    Value *RealVal = operator[](ResolveConstants.back().second);
300    Constant *Placeholder = ResolveConstants.back().first;
301    ResolveConstants.pop_back();
302
303    // Loop over all users of the placeholder, updating them to reference the
304    // new value.  If they reference more than one placeholder, update them all
305    // at once.
306    while (!Placeholder->use_empty()) {
307      Value::use_iterator UI = Placeholder->use_begin();
308      User *U = *UI;
309
310      // If the using object isn't uniqued, just update the operands.  This
311      // handles instructions and initializers for global variables.
312      if (!isa<Constant>(U) || isa<GlobalValue>(U)) {
313        UI.getUse().set(RealVal);
314        continue;
315      }
316
317      // Otherwise, we have a constant that uses the placeholder.  Replace that
318      // constant with a new constant that has *all* placeholder uses updated.
319      Constant *UserC = cast<Constant>(U);
320      for (User::op_iterator I = UserC->op_begin(), E = UserC->op_end();
321           I != E; ++I) {
322        Value *NewOp;
323        if (!isa<ConstantPlaceHolder>(*I)) {
324          // Not a placeholder reference.
325          NewOp = *I;
326        } else if (*I == Placeholder) {
327          // Common case is that it just references this one placeholder.
328          NewOp = RealVal;
329        } else {
330          // Otherwise, look up the placeholder in ResolveConstants.
331          ResolveConstantsTy::iterator It =
332            std::lower_bound(ResolveConstants.begin(), ResolveConstants.end(),
333                             std::pair<Constant*, unsigned>(cast<Constant>(*I),
334                                                            0));
335          assert(It != ResolveConstants.end() && It->first == *I);
336          NewOp = operator[](It->second);
337        }
338
339        NewOps.push_back(cast<Constant>(NewOp));
340      }
341
342      // Make the new constant.
343      Constant *NewC;
344      if (ConstantArray *UserCA = dyn_cast<ConstantArray>(UserC)) {
345        NewC = ConstantArray::get(UserCA->getType(), NewOps);
346      } else if (ConstantStruct *UserCS = dyn_cast<ConstantStruct>(UserC)) {
347        NewC = ConstantStruct::get(UserCS->getType(), NewOps);
348      } else if (isa<ConstantVector>(UserC)) {
349        NewC = ConstantVector::get(NewOps);
350      } else {
351        assert(isa<ConstantExpr>(UserC) && "Must be a ConstantExpr.");
352        NewC = cast<ConstantExpr>(UserC)->getWithOperands(NewOps);
353      }
354
355      UserC->replaceAllUsesWith(NewC);
356      UserC->destroyConstant();
357      NewOps.clear();
358    }
359
360    // Update all ValueHandles, they should be the only users at this point.
361    Placeholder->replaceAllUsesWith(RealVal);
362    delete Placeholder;
363  }
364}
365
366void BitcodeReaderMDValueList::AssignValue(Value *V, unsigned Idx) {
367  if (Idx == size()) {
368    push_back(V);
369    return;
370  }
371
372  if (Idx >= size())
373    resize(Idx+1);
374
375  WeakVH &OldV = MDValuePtrs[Idx];
376  if (OldV == 0) {
377    OldV = V;
378    return;
379  }
380
381  // If there was a forward reference to this value, replace it.
382  MDNode *PrevVal = cast<MDNode>(OldV);
383  OldV->replaceAllUsesWith(V);
384  MDNode::deleteTemporary(PrevVal);
385  // Deleting PrevVal sets Idx value in MDValuePtrs to null. Set new
386  // value for Idx.
387  MDValuePtrs[Idx] = V;
388}
389
390Value *BitcodeReaderMDValueList::getValueFwdRef(unsigned Idx) {
391  if (Idx >= size())
392    resize(Idx + 1);
393
394  if (Value *V = MDValuePtrs[Idx]) {
395    assert(V->getType()->isMetadataTy() && "Type mismatch in value table!");
396    return V;
397  }
398
399  // Create and return a placeholder, which will later be RAUW'd.
400  Value *V = MDNode::getTemporary(Context, ArrayRef<Value*>());
401  MDValuePtrs[Idx] = V;
402  return V;
403}
404
405Type *BitcodeReader::getTypeByID(unsigned ID) {
406  // The type table size is always specified correctly.
407  if (ID >= TypeList.size())
408    return 0;
409
410  if (Type *Ty = TypeList[ID])
411    return Ty;
412
413  // If we have a forward reference, the only possible case is when it is to a
414  // named struct.  Just create a placeholder for now.
415  return TypeList[ID] = StructType::create(Context);
416}
417
418
419//===----------------------------------------------------------------------===//
420//  Functions for parsing blocks from the bitcode file
421//===----------------------------------------------------------------------===//
422
423bool BitcodeReader::ParseAttributeBlock() {
424  if (Stream.EnterSubBlock(bitc::PARAMATTR_BLOCK_ID))
425    return Error("Malformed block record");
426
427  if (!MAttributes.empty())
428    return Error("Multiple PARAMATTR blocks found!");
429
430  SmallVector<uint64_t, 64> Record;
431
432  SmallVector<AttributeWithIndex, 8> Attrs;
433
434  // Read all the records.
435  while (1) {
436    unsigned Code = Stream.ReadCode();
437    if (Code == bitc::END_BLOCK) {
438      if (Stream.ReadBlockEnd())
439        return Error("Error at end of PARAMATTR block");
440      return false;
441    }
442
443    if (Code == bitc::ENTER_SUBBLOCK) {
444      // No known subblocks, always skip them.
445      Stream.ReadSubBlockID();
446      if (Stream.SkipBlock())
447        return Error("Malformed block record");
448      continue;
449    }
450
451    if (Code == bitc::DEFINE_ABBREV) {
452      Stream.ReadAbbrevRecord();
453      continue;
454    }
455
456    // Read a record.
457    Record.clear();
458    switch (Stream.ReadRecord(Code, Record)) {
459    default:  // Default behavior: ignore.
460      break;
461    case bitc::PARAMATTR_CODE_ENTRY: { // ENTRY: [paramidx0, attr0, ...]
462      if (Record.size() & 1)
463        return Error("Invalid ENTRY record");
464
465      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
466        // FIXME: remove in LLVM 3.0
467        // The alignment is stored as a 16-bit raw value from bits 31--16.
468        // We shift the bits above 31 down by 11 bits.
469
470        unsigned Alignment = (Record[i+1] & (0xffffull << 16)) >> 16;
471        if (Alignment && !isPowerOf2_32(Alignment))
472          return Error("Alignment is not a power of two.");
473
474        Attributes ReconstitutedAttr(Record[i+1] & 0xffff);
475        if (Alignment)
476          ReconstitutedAttr |= Attribute::constructAlignmentFromInt(Alignment);
477        ReconstitutedAttr |=
478            Attributes((Record[i+1] & (0xffffull << 32)) >> 11);
479
480        Record[i+1] = ReconstitutedAttr.Raw();
481      }
482
483      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
484        if (Attributes(Record[i+1]) != Attribute::None)
485          Attrs.push_back(AttributeWithIndex::get(Record[i],
486                                                  Attributes(Record[i+1])));
487      }
488
489      MAttributes.push_back(AttrListPtr::get(Attrs.begin(), Attrs.end()));
490      Attrs.clear();
491      break;
492    }
493    }
494  }
495}
496
497bool BitcodeReader::ParseTypeTable() {
498  if (Stream.EnterSubBlock(bitc::TYPE_BLOCK_ID_NEW))
499    return Error("Malformed block record");
500
501  return ParseTypeTableBody();
502}
503
504bool BitcodeReader::ParseTypeTableBody() {
505  if (!TypeList.empty())
506    return Error("Multiple TYPE_BLOCKs found!");
507
508  SmallVector<uint64_t, 64> Record;
509  unsigned NumRecords = 0;
510
511  SmallString<64> TypeName;
512
513  // Read all the records for this type table.
514  while (1) {
515    unsigned Code = Stream.ReadCode();
516    if (Code == bitc::END_BLOCK) {
517      if (NumRecords != TypeList.size())
518        return Error("Invalid type forward reference in TYPE_BLOCK");
519      if (Stream.ReadBlockEnd())
520        return Error("Error at end of type table block");
521      return false;
522    }
523
524    if (Code == bitc::ENTER_SUBBLOCK) {
525      // No known subblocks, always skip them.
526      Stream.ReadSubBlockID();
527      if (Stream.SkipBlock())
528        return Error("Malformed block record");
529      continue;
530    }
531
532    if (Code == bitc::DEFINE_ABBREV) {
533      Stream.ReadAbbrevRecord();
534      continue;
535    }
536
537    // Read a record.
538    Record.clear();
539    Type *ResultTy = 0;
540    switch (Stream.ReadRecord(Code, Record)) {
541    default: return Error("unknown type in type table");
542    case bitc::TYPE_CODE_NUMENTRY: // TYPE_CODE_NUMENTRY: [numentries]
543      // TYPE_CODE_NUMENTRY contains a count of the number of types in the
544      // type list.  This allows us to reserve space.
545      if (Record.size() < 1)
546        return Error("Invalid TYPE_CODE_NUMENTRY record");
547      TypeList.resize(Record[0]);
548      continue;
549    case bitc::TYPE_CODE_VOID:      // VOID
550      ResultTy = Type::getVoidTy(Context);
551      break;
552    case bitc::TYPE_CODE_HALF:     // HALF
553      ResultTy = Type::getHalfTy(Context);
554      break;
555    case bitc::TYPE_CODE_FLOAT:     // FLOAT
556      ResultTy = Type::getFloatTy(Context);
557      break;
558    case bitc::TYPE_CODE_DOUBLE:    // DOUBLE
559      ResultTy = Type::getDoubleTy(Context);
560      break;
561    case bitc::TYPE_CODE_X86_FP80:  // X86_FP80
562      ResultTy = Type::getX86_FP80Ty(Context);
563      break;
564    case bitc::TYPE_CODE_FP128:     // FP128
565      ResultTy = Type::getFP128Ty(Context);
566      break;
567    case bitc::TYPE_CODE_PPC_FP128: // PPC_FP128
568      ResultTy = Type::getPPC_FP128Ty(Context);
569      break;
570    case bitc::TYPE_CODE_LABEL:     // LABEL
571      ResultTy = Type::getLabelTy(Context);
572      break;
573    case bitc::TYPE_CODE_METADATA:  // METADATA
574      ResultTy = Type::getMetadataTy(Context);
575      break;
576    case bitc::TYPE_CODE_X86_MMX:   // X86_MMX
577      ResultTy = Type::getX86_MMXTy(Context);
578      break;
579    case bitc::TYPE_CODE_INTEGER:   // INTEGER: [width]
580      if (Record.size() < 1)
581        return Error("Invalid Integer type record");
582
583      ResultTy = IntegerType::get(Context, Record[0]);
584      break;
585    case bitc::TYPE_CODE_POINTER: { // POINTER: [pointee type] or
586                                    //          [pointee type, address space]
587      if (Record.size() < 1)
588        return Error("Invalid POINTER type record");
589      unsigned AddressSpace = 0;
590      if (Record.size() == 2)
591        AddressSpace = Record[1];
592      ResultTy = getTypeByID(Record[0]);
593      if (ResultTy == 0) return Error("invalid element type in pointer type");
594      ResultTy = PointerType::get(ResultTy, AddressSpace);
595      break;
596    }
597    case bitc::TYPE_CODE_FUNCTION: {
598      // FUNCTION: [vararg, retty, paramty x N]
599      if (Record.size() < 2)
600        return Error("Invalid FUNCTION type record");
601      SmallVector<Type*, 8> ArgTys;
602      for (unsigned i = 2, e = Record.size(); i != e; ++i) {
603        if (Type *T = getTypeByID(Record[i]))
604          ArgTys.push_back(T);
605        else
606          break;
607      }
608
609      ResultTy = getTypeByID(Record[1]);
610      if (ResultTy == 0 || ArgTys.size() < Record.size()-2)
611        return Error("invalid type in function type");
612
613      ResultTy = FunctionType::get(ResultTy, ArgTys, Record[0]);
614      break;
615    }
616    case bitc::TYPE_CODE_STRUCT_ANON: {  // STRUCT: [ispacked, eltty x N]
617      if (Record.size() < 1)
618        return Error("Invalid STRUCT type record");
619      SmallVector<Type*, 8> EltTys;
620      for (unsigned i = 1, e = Record.size(); i != e; ++i) {
621        if (Type *T = getTypeByID(Record[i]))
622          EltTys.push_back(T);
623        else
624          break;
625      }
626      if (EltTys.size() != Record.size()-1)
627        return Error("invalid type in struct type");
628      ResultTy = StructType::get(Context, EltTys, Record[0]);
629      break;
630    }
631    case bitc::TYPE_CODE_STRUCT_NAME:   // STRUCT_NAME: [strchr x N]
632      if (ConvertToString(Record, 0, TypeName))
633        return Error("Invalid STRUCT_NAME record");
634      continue;
635
636    case bitc::TYPE_CODE_STRUCT_NAMED: { // STRUCT: [ispacked, eltty x N]
637      if (Record.size() < 1)
638        return Error("Invalid STRUCT type record");
639
640      if (NumRecords >= TypeList.size())
641        return Error("invalid TYPE table");
642
643      // Check to see if this was forward referenced, if so fill in the temp.
644      StructType *Res = cast_or_null<StructType>(TypeList[NumRecords]);
645      if (Res) {
646        Res->setName(TypeName);
647        TypeList[NumRecords] = 0;
648      } else  // Otherwise, create a new struct.
649        Res = StructType::create(Context, TypeName);
650      TypeName.clear();
651
652      SmallVector<Type*, 8> EltTys;
653      for (unsigned i = 1, e = Record.size(); i != e; ++i) {
654        if (Type *T = getTypeByID(Record[i]))
655          EltTys.push_back(T);
656        else
657          break;
658      }
659      if (EltTys.size() != Record.size()-1)
660        return Error("invalid STRUCT type record");
661      Res->setBody(EltTys, Record[0]);
662      ResultTy = Res;
663      break;
664    }
665    case bitc::TYPE_CODE_OPAQUE: {       // OPAQUE: []
666      if (Record.size() != 1)
667        return Error("Invalid OPAQUE type record");
668
669      if (NumRecords >= TypeList.size())
670        return Error("invalid TYPE table");
671
672      // Check to see if this was forward referenced, if so fill in the temp.
673      StructType *Res = cast_or_null<StructType>(TypeList[NumRecords]);
674      if (Res) {
675        Res->setName(TypeName);
676        TypeList[NumRecords] = 0;
677      } else  // Otherwise, create a new struct with no body.
678        Res = StructType::create(Context, TypeName);
679      TypeName.clear();
680      ResultTy = Res;
681      break;
682    }
683    case bitc::TYPE_CODE_ARRAY:     // ARRAY: [numelts, eltty]
684      if (Record.size() < 2)
685        return Error("Invalid ARRAY type record");
686      if ((ResultTy = getTypeByID(Record[1])))
687        ResultTy = ArrayType::get(ResultTy, Record[0]);
688      else
689        return Error("Invalid ARRAY type element");
690      break;
691    case bitc::TYPE_CODE_VECTOR:    // VECTOR: [numelts, eltty]
692      if (Record.size() < 2)
693        return Error("Invalid VECTOR type record");
694      if ((ResultTy = getTypeByID(Record[1])))
695        ResultTy = VectorType::get(ResultTy, Record[0]);
696      else
697        return Error("Invalid ARRAY type element");
698      break;
699    }
700
701    if (NumRecords >= TypeList.size())
702      return Error("invalid TYPE table");
703    assert(ResultTy && "Didn't read a type?");
704    assert(TypeList[NumRecords] == 0 && "Already read type?");
705    TypeList[NumRecords++] = ResultTy;
706  }
707}
708
709bool BitcodeReader::ParseValueSymbolTable() {
710  if (Stream.EnterSubBlock(bitc::VALUE_SYMTAB_BLOCK_ID))
711    return Error("Malformed block record");
712
713  SmallVector<uint64_t, 64> Record;
714
715  // Read all the records for this value table.
716  SmallString<128> ValueName;
717  while (1) {
718    unsigned Code = Stream.ReadCode();
719    if (Code == bitc::END_BLOCK) {
720      if (Stream.ReadBlockEnd())
721        return Error("Error at end of value symbol table block");
722      return false;
723    }
724    if (Code == bitc::ENTER_SUBBLOCK) {
725      // No known subblocks, always skip them.
726      Stream.ReadSubBlockID();
727      if (Stream.SkipBlock())
728        return Error("Malformed block record");
729      continue;
730    }
731
732    if (Code == bitc::DEFINE_ABBREV) {
733      Stream.ReadAbbrevRecord();
734      continue;
735    }
736
737    // Read a record.
738    Record.clear();
739    switch (Stream.ReadRecord(Code, Record)) {
740    default:  // Default behavior: unknown type.
741      break;
742    case bitc::VST_CODE_ENTRY: {  // VST_ENTRY: [valueid, namechar x N]
743      if (ConvertToString(Record, 1, ValueName))
744        return Error("Invalid VST_ENTRY record");
745      unsigned ValueID = Record[0];
746      if (ValueID >= ValueList.size())
747        return Error("Invalid Value ID in VST_ENTRY record");
748      Value *V = ValueList[ValueID];
749
750      V->setName(StringRef(ValueName.data(), ValueName.size()));
751      ValueName.clear();
752      break;
753    }
754    case bitc::VST_CODE_BBENTRY: {
755      if (ConvertToString(Record, 1, ValueName))
756        return Error("Invalid VST_BBENTRY record");
757      BasicBlock *BB = getBasicBlock(Record[0]);
758      if (BB == 0)
759        return Error("Invalid BB ID in VST_BBENTRY record");
760
761      BB->setName(StringRef(ValueName.data(), ValueName.size()));
762      ValueName.clear();
763      break;
764    }
765    }
766  }
767}
768
769bool BitcodeReader::ParseMetadata() {
770  unsigned NextMDValueNo = MDValueList.size();
771
772  if (Stream.EnterSubBlock(bitc::METADATA_BLOCK_ID))
773    return Error("Malformed block record");
774
775  SmallVector<uint64_t, 64> Record;
776
777  // Read all the records.
778  while (1) {
779    unsigned Code = Stream.ReadCode();
780    if (Code == bitc::END_BLOCK) {
781      if (Stream.ReadBlockEnd())
782        return Error("Error at end of PARAMATTR block");
783      return false;
784    }
785
786    if (Code == bitc::ENTER_SUBBLOCK) {
787      // No known subblocks, always skip them.
788      Stream.ReadSubBlockID();
789      if (Stream.SkipBlock())
790        return Error("Malformed block record");
791      continue;
792    }
793
794    if (Code == bitc::DEFINE_ABBREV) {
795      Stream.ReadAbbrevRecord();
796      continue;
797    }
798
799    bool IsFunctionLocal = false;
800    // Read a record.
801    Record.clear();
802    Code = Stream.ReadRecord(Code, Record);
803    switch (Code) {
804    default:  // Default behavior: ignore.
805      break;
806    case bitc::METADATA_NAME: {
807      // Read named of the named metadata.
808      unsigned NameLength = Record.size();
809      SmallString<8> Name;
810      Name.resize(NameLength);
811      for (unsigned i = 0; i != NameLength; ++i)
812        Name[i] = Record[i];
813      Record.clear();
814      Code = Stream.ReadCode();
815
816      // METADATA_NAME is always followed by METADATA_NAMED_NODE.
817      unsigned NextBitCode = Stream.ReadRecord(Code, Record);
818      assert(NextBitCode == bitc::METADATA_NAMED_NODE); (void)NextBitCode;
819
820      // Read named metadata elements.
821      unsigned Size = Record.size();
822      NamedMDNode *NMD = TheModule->getOrInsertNamedMetadata(Name);
823      for (unsigned i = 0; i != Size; ++i) {
824        MDNode *MD = dyn_cast<MDNode>(MDValueList.getValueFwdRef(Record[i]));
825        if (MD == 0)
826          return Error("Malformed metadata record");
827        NMD->addOperand(MD);
828      }
829      break;
830    }
831    case bitc::METADATA_FN_NODE:
832      IsFunctionLocal = true;
833      // fall-through
834    case bitc::METADATA_NODE: {
835      if (Record.size() % 2 == 1)
836        return Error("Invalid METADATA_NODE record");
837
838      unsigned Size = Record.size();
839      SmallVector<Value*, 8> Elts;
840      for (unsigned i = 0; i != Size; i += 2) {
841        Type *Ty = getTypeByID(Record[i]);
842        if (!Ty) return Error("Invalid METADATA_NODE record");
843        if (Ty->isMetadataTy())
844          Elts.push_back(MDValueList.getValueFwdRef(Record[i+1]));
845        else if (!Ty->isVoidTy())
846          Elts.push_back(ValueList.getValueFwdRef(Record[i+1], Ty));
847        else
848          Elts.push_back(NULL);
849      }
850      Value *V = MDNode::getWhenValsUnresolved(Context, Elts, IsFunctionLocal);
851      IsFunctionLocal = false;
852      MDValueList.AssignValue(V, NextMDValueNo++);
853      break;
854    }
855    case bitc::METADATA_STRING: {
856      unsigned MDStringLength = Record.size();
857      SmallString<8> String;
858      String.resize(MDStringLength);
859      for (unsigned i = 0; i != MDStringLength; ++i)
860        String[i] = Record[i];
861      Value *V = MDString::get(Context,
862                               StringRef(String.data(), String.size()));
863      MDValueList.AssignValue(V, NextMDValueNo++);
864      break;
865    }
866    case bitc::METADATA_KIND: {
867      unsigned RecordLength = Record.size();
868      if (Record.empty() || RecordLength < 2)
869        return Error("Invalid METADATA_KIND record");
870      SmallString<8> Name;
871      Name.resize(RecordLength-1);
872      unsigned Kind = Record[0];
873      for (unsigned i = 1; i != RecordLength; ++i)
874        Name[i-1] = Record[i];
875
876      unsigned NewKind = TheModule->getMDKindID(Name.str());
877      if (!MDKindMap.insert(std::make_pair(Kind, NewKind)).second)
878        return Error("Conflicting METADATA_KIND records");
879      break;
880    }
881    }
882  }
883}
884
885/// DecodeSignRotatedValue - Decode a signed value stored with the sign bit in
886/// the LSB for dense VBR encoding.
887static uint64_t DecodeSignRotatedValue(uint64_t V) {
888  if ((V & 1) == 0)
889    return V >> 1;
890  if (V != 1)
891    return -(V >> 1);
892  // There is no such thing as -0 with integers.  "-0" really means MININT.
893  return 1ULL << 63;
894}
895
896/// ResolveGlobalAndAliasInits - Resolve all of the initializers for global
897/// values and aliases that we can.
898bool BitcodeReader::ResolveGlobalAndAliasInits() {
899  std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInitWorklist;
900  std::vector<std::pair<GlobalAlias*, unsigned> > AliasInitWorklist;
901
902  GlobalInitWorklist.swap(GlobalInits);
903  AliasInitWorklist.swap(AliasInits);
904
905  while (!GlobalInitWorklist.empty()) {
906    unsigned ValID = GlobalInitWorklist.back().second;
907    if (ValID >= ValueList.size()) {
908      // Not ready to resolve this yet, it requires something later in the file.
909      GlobalInits.push_back(GlobalInitWorklist.back());
910    } else {
911      if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
912        GlobalInitWorklist.back().first->setInitializer(C);
913      else
914        return Error("Global variable initializer is not a constant!");
915    }
916    GlobalInitWorklist.pop_back();
917  }
918
919  while (!AliasInitWorklist.empty()) {
920    unsigned ValID = AliasInitWorklist.back().second;
921    if (ValID >= ValueList.size()) {
922      AliasInits.push_back(AliasInitWorklist.back());
923    } else {
924      if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
925        AliasInitWorklist.back().first->setAliasee(C);
926      else
927        return Error("Alias initializer is not a constant!");
928    }
929    AliasInitWorklist.pop_back();
930  }
931  return false;
932}
933
934APInt ReadWideAPInt(const uint64_t *Vals, unsigned ActiveWords,
935                    unsigned TypeBits) {
936  SmallVector<uint64_t, 8> Words;
937  Words.resize(ActiveWords);
938  for (unsigned i = 0; i != ActiveWords; ++i)
939    Words[i] = DecodeSignRotatedValue(Vals[i]);
940
941  return APInt(TypeBits, Words);
942}
943
944bool BitcodeReader::ParseConstants() {
945  if (Stream.EnterSubBlock(bitc::CONSTANTS_BLOCK_ID))
946    return Error("Malformed block record");
947
948  SmallVector<uint64_t, 64> Record;
949
950  // Read all the records for this value table.
951  Type *CurTy = Type::getInt32Ty(Context);
952  unsigned NextCstNo = ValueList.size();
953  while (1) {
954    unsigned Code = Stream.ReadCode();
955    if (Code == bitc::END_BLOCK)
956      break;
957
958    if (Code == bitc::ENTER_SUBBLOCK) {
959      // No known subblocks, always skip them.
960      Stream.ReadSubBlockID();
961      if (Stream.SkipBlock())
962        return Error("Malformed block record");
963      continue;
964    }
965
966    if (Code == bitc::DEFINE_ABBREV) {
967      Stream.ReadAbbrevRecord();
968      continue;
969    }
970
971    // Read a record.
972    Record.clear();
973    Value *V = 0;
974    unsigned BitCode = Stream.ReadRecord(Code, Record);
975    switch (BitCode) {
976    default:  // Default behavior: unknown constant
977    case bitc::CST_CODE_UNDEF:     // UNDEF
978      V = UndefValue::get(CurTy);
979      break;
980    case bitc::CST_CODE_SETTYPE:   // SETTYPE: [typeid]
981      if (Record.empty())
982        return Error("Malformed CST_SETTYPE record");
983      if (Record[0] >= TypeList.size())
984        return Error("Invalid Type ID in CST_SETTYPE record");
985      CurTy = TypeList[Record[0]];
986      continue;  // Skip the ValueList manipulation.
987    case bitc::CST_CODE_NULL:      // NULL
988      V = Constant::getNullValue(CurTy);
989      break;
990    case bitc::CST_CODE_INTEGER:   // INTEGER: [intval]
991      if (!CurTy->isIntegerTy() || Record.empty())
992        return Error("Invalid CST_INTEGER record");
993      V = ConstantInt::get(CurTy, DecodeSignRotatedValue(Record[0]));
994      break;
995    case bitc::CST_CODE_WIDE_INTEGER: {// WIDE_INTEGER: [n x intval]
996      if (!CurTy->isIntegerTy() || Record.empty())
997        return Error("Invalid WIDE_INTEGER record");
998
999      unsigned NumWords = Record.size();
1000
1001      APInt VInt = ReadWideAPInt(&Record[0], NumWords,
1002          cast<IntegerType>(CurTy)->getBitWidth());
1003      V = ConstantInt::get(Context, VInt);
1004
1005      break;
1006    }
1007    case bitc::CST_CODE_FLOAT: {    // FLOAT: [fpval]
1008      if (Record.empty())
1009        return Error("Invalid FLOAT record");
1010      if (CurTy->isHalfTy())
1011        V = ConstantFP::get(Context, APFloat(APInt(16, (uint16_t)Record[0])));
1012      else if (CurTy->isFloatTy())
1013        V = ConstantFP::get(Context, APFloat(APInt(32, (uint32_t)Record[0])));
1014      else if (CurTy->isDoubleTy())
1015        V = ConstantFP::get(Context, APFloat(APInt(64, Record[0])));
1016      else if (CurTy->isX86_FP80Ty()) {
1017        // Bits are not stored the same way as a normal i80 APInt, compensate.
1018        uint64_t Rearrange[2];
1019        Rearrange[0] = (Record[1] & 0xffffLL) | (Record[0] << 16);
1020        Rearrange[1] = Record[0] >> 48;
1021        V = ConstantFP::get(Context, APFloat(APInt(80, Rearrange)));
1022      } else if (CurTy->isFP128Ty())
1023        V = ConstantFP::get(Context, APFloat(APInt(128, Record), true));
1024      else if (CurTy->isPPC_FP128Ty())
1025        V = ConstantFP::get(Context, APFloat(APInt(128, Record)));
1026      else
1027        V = UndefValue::get(CurTy);
1028      break;
1029    }
1030
1031    case bitc::CST_CODE_AGGREGATE: {// AGGREGATE: [n x value number]
1032      if (Record.empty())
1033        return Error("Invalid CST_AGGREGATE record");
1034
1035      unsigned Size = Record.size();
1036      SmallVector<Constant*, 16> Elts;
1037
1038      if (StructType *STy = dyn_cast<StructType>(CurTy)) {
1039        for (unsigned i = 0; i != Size; ++i)
1040          Elts.push_back(ValueList.getConstantFwdRef(Record[i],
1041                                                     STy->getElementType(i)));
1042        V = ConstantStruct::get(STy, Elts);
1043      } else if (ArrayType *ATy = dyn_cast<ArrayType>(CurTy)) {
1044        Type *EltTy = ATy->getElementType();
1045        for (unsigned i = 0; i != Size; ++i)
1046          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
1047        V = ConstantArray::get(ATy, Elts);
1048      } else if (VectorType *VTy = dyn_cast<VectorType>(CurTy)) {
1049        Type *EltTy = VTy->getElementType();
1050        for (unsigned i = 0; i != Size; ++i)
1051          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
1052        V = ConstantVector::get(Elts);
1053      } else {
1054        V = UndefValue::get(CurTy);
1055      }
1056      break;
1057    }
1058    case bitc::CST_CODE_STRING:    // STRING: [values]
1059    case bitc::CST_CODE_CSTRING: { // CSTRING: [values]
1060      if (Record.empty())
1061        return Error("Invalid CST_STRING record");
1062
1063      unsigned Size = Record.size();
1064      SmallString<16> Elts;
1065      for (unsigned i = 0; i != Size; ++i)
1066        Elts.push_back(Record[i]);
1067      V = ConstantDataArray::getString(Context, Elts,
1068                                       BitCode == bitc::CST_CODE_CSTRING);
1069      break;
1070    }
1071    case bitc::CST_CODE_DATA: {// DATA: [n x value]
1072      if (Record.empty())
1073        return Error("Invalid CST_DATA record");
1074
1075      Type *EltTy = cast<SequentialType>(CurTy)->getElementType();
1076      unsigned Size = Record.size();
1077
1078      if (EltTy->isIntegerTy(8)) {
1079        SmallVector<uint8_t, 16> Elts(Record.begin(), Record.end());
1080        if (isa<VectorType>(CurTy))
1081          V = ConstantDataVector::get(Context, Elts);
1082        else
1083          V = ConstantDataArray::get(Context, Elts);
1084      } else if (EltTy->isIntegerTy(16)) {
1085        SmallVector<uint16_t, 16> Elts(Record.begin(), Record.end());
1086        if (isa<VectorType>(CurTy))
1087          V = ConstantDataVector::get(Context, Elts);
1088        else
1089          V = ConstantDataArray::get(Context, Elts);
1090      } else if (EltTy->isIntegerTy(32)) {
1091        SmallVector<uint32_t, 16> Elts(Record.begin(), Record.end());
1092        if (isa<VectorType>(CurTy))
1093          V = ConstantDataVector::get(Context, Elts);
1094        else
1095          V = ConstantDataArray::get(Context, Elts);
1096      } else if (EltTy->isIntegerTy(64)) {
1097        SmallVector<uint64_t, 16> Elts(Record.begin(), Record.end());
1098        if (isa<VectorType>(CurTy))
1099          V = ConstantDataVector::get(Context, Elts);
1100        else
1101          V = ConstantDataArray::get(Context, Elts);
1102      } else if (EltTy->isFloatTy()) {
1103        SmallVector<float, 16> Elts;
1104        for (unsigned i = 0; i != Size; ++i) {
1105          union { uint32_t I; float F; };
1106          I = Record[i];
1107          Elts.push_back(F);
1108        }
1109        if (isa<VectorType>(CurTy))
1110          V = ConstantDataVector::get(Context, Elts);
1111        else
1112          V = ConstantDataArray::get(Context, Elts);
1113      } else if (EltTy->isDoubleTy()) {
1114        SmallVector<double, 16> Elts;
1115        for (unsigned i = 0; i != Size; ++i) {
1116          union { uint64_t I; double F; };
1117          I = Record[i];
1118          Elts.push_back(F);
1119        }
1120        if (isa<VectorType>(CurTy))
1121          V = ConstantDataVector::get(Context, Elts);
1122        else
1123          V = ConstantDataArray::get(Context, Elts);
1124      } else {
1125        return Error("Unknown element type in CE_DATA");
1126      }
1127      break;
1128    }
1129
1130    case bitc::CST_CODE_CE_BINOP: {  // CE_BINOP: [opcode, opval, opval]
1131      if (Record.size() < 3) return Error("Invalid CE_BINOP record");
1132      int Opc = GetDecodedBinaryOpcode(Record[0], CurTy);
1133      if (Opc < 0) {
1134        V = UndefValue::get(CurTy);  // Unknown binop.
1135      } else {
1136        Constant *LHS = ValueList.getConstantFwdRef(Record[1], CurTy);
1137        Constant *RHS = ValueList.getConstantFwdRef(Record[2], CurTy);
1138        unsigned Flags = 0;
1139        if (Record.size() >= 4) {
1140          if (Opc == Instruction::Add ||
1141              Opc == Instruction::Sub ||
1142              Opc == Instruction::Mul ||
1143              Opc == Instruction::Shl) {
1144            if (Record[3] & (1 << bitc::OBO_NO_SIGNED_WRAP))
1145              Flags |= OverflowingBinaryOperator::NoSignedWrap;
1146            if (Record[3] & (1 << bitc::OBO_NO_UNSIGNED_WRAP))
1147              Flags |= OverflowingBinaryOperator::NoUnsignedWrap;
1148          } else if (Opc == Instruction::SDiv ||
1149                     Opc == Instruction::UDiv ||
1150                     Opc == Instruction::LShr ||
1151                     Opc == Instruction::AShr) {
1152            if (Record[3] & (1 << bitc::PEO_EXACT))
1153              Flags |= SDivOperator::IsExact;
1154          }
1155        }
1156        V = ConstantExpr::get(Opc, LHS, RHS, Flags);
1157      }
1158      break;
1159    }
1160    case bitc::CST_CODE_CE_CAST: {  // CE_CAST: [opcode, opty, opval]
1161      if (Record.size() < 3) return Error("Invalid CE_CAST record");
1162      int Opc = GetDecodedCastOpcode(Record[0]);
1163      if (Opc < 0) {
1164        V = UndefValue::get(CurTy);  // Unknown cast.
1165      } else {
1166        Type *OpTy = getTypeByID(Record[1]);
1167        if (!OpTy) return Error("Invalid CE_CAST record");
1168        Constant *Op = ValueList.getConstantFwdRef(Record[2], OpTy);
1169        V = ConstantExpr::getCast(Opc, Op, CurTy);
1170      }
1171      break;
1172    }
1173    case bitc::CST_CODE_CE_INBOUNDS_GEP:
1174    case bitc::CST_CODE_CE_GEP: {  // CE_GEP:        [n x operands]
1175      if (Record.size() & 1) return Error("Invalid CE_GEP record");
1176      SmallVector<Constant*, 16> Elts;
1177      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
1178        Type *ElTy = getTypeByID(Record[i]);
1179        if (!ElTy) return Error("Invalid CE_GEP record");
1180        Elts.push_back(ValueList.getConstantFwdRef(Record[i+1], ElTy));
1181      }
1182      ArrayRef<Constant *> Indices(Elts.begin() + 1, Elts.end());
1183      V = ConstantExpr::getGetElementPtr(Elts[0], Indices,
1184                                         BitCode ==
1185                                           bitc::CST_CODE_CE_INBOUNDS_GEP);
1186      break;
1187    }
1188    case bitc::CST_CODE_CE_SELECT:  // CE_SELECT: [opval#, opval#, opval#]
1189      if (Record.size() < 3) return Error("Invalid CE_SELECT record");
1190      V = ConstantExpr::getSelect(ValueList.getConstantFwdRef(Record[0],
1191                                                              Type::getInt1Ty(Context)),
1192                                  ValueList.getConstantFwdRef(Record[1],CurTy),
1193                                  ValueList.getConstantFwdRef(Record[2],CurTy));
1194      break;
1195    case bitc::CST_CODE_CE_EXTRACTELT: { // CE_EXTRACTELT: [opty, opval, opval]
1196      if (Record.size() < 3) return Error("Invalid CE_EXTRACTELT record");
1197      VectorType *OpTy =
1198        dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
1199      if (OpTy == 0) return Error("Invalid CE_EXTRACTELT record");
1200      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1201      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], Type::getInt32Ty(Context));
1202      V = ConstantExpr::getExtractElement(Op0, Op1);
1203      break;
1204    }
1205    case bitc::CST_CODE_CE_INSERTELT: { // CE_INSERTELT: [opval, opval, opval]
1206      VectorType *OpTy = dyn_cast<VectorType>(CurTy);
1207      if (Record.size() < 3 || OpTy == 0)
1208        return Error("Invalid CE_INSERTELT record");
1209      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
1210      Constant *Op1 = ValueList.getConstantFwdRef(Record[1],
1211                                                  OpTy->getElementType());
1212      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], Type::getInt32Ty(Context));
1213      V = ConstantExpr::getInsertElement(Op0, Op1, Op2);
1214      break;
1215    }
1216    case bitc::CST_CODE_CE_SHUFFLEVEC: { // CE_SHUFFLEVEC: [opval, opval, opval]
1217      VectorType *OpTy = dyn_cast<VectorType>(CurTy);
1218      if (Record.size() < 3 || OpTy == 0)
1219        return Error("Invalid CE_SHUFFLEVEC record");
1220      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
1221      Constant *Op1 = ValueList.getConstantFwdRef(Record[1], OpTy);
1222      Type *ShufTy = VectorType::get(Type::getInt32Ty(Context),
1223                                                 OpTy->getNumElements());
1224      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], ShufTy);
1225      V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
1226      break;
1227    }
1228    case bitc::CST_CODE_CE_SHUFVEC_EX: { // [opty, opval, opval, opval]
1229      VectorType *RTy = dyn_cast<VectorType>(CurTy);
1230      VectorType *OpTy =
1231        dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
1232      if (Record.size() < 4 || RTy == 0 || OpTy == 0)
1233        return Error("Invalid CE_SHUFVEC_EX record");
1234      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1235      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
1236      Type *ShufTy = VectorType::get(Type::getInt32Ty(Context),
1237                                                 RTy->getNumElements());
1238      Constant *Op2 = ValueList.getConstantFwdRef(Record[3], ShufTy);
1239      V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
1240      break;
1241    }
1242    case bitc::CST_CODE_CE_CMP: {     // CE_CMP: [opty, opval, opval, pred]
1243      if (Record.size() < 4) return Error("Invalid CE_CMP record");
1244      Type *OpTy = getTypeByID(Record[0]);
1245      if (OpTy == 0) return Error("Invalid CE_CMP record");
1246      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1247      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
1248
1249      if (OpTy->isFPOrFPVectorTy())
1250        V = ConstantExpr::getFCmp(Record[3], Op0, Op1);
1251      else
1252        V = ConstantExpr::getICmp(Record[3], Op0, Op1);
1253      break;
1254    }
1255    case bitc::CST_CODE_INLINEASM: {
1256      if (Record.size() < 2) return Error("Invalid INLINEASM record");
1257      std::string AsmStr, ConstrStr;
1258      bool HasSideEffects = Record[0] & 1;
1259      bool IsAlignStack = Record[0] >> 1;
1260      unsigned AsmStrSize = Record[1];
1261      if (2+AsmStrSize >= Record.size())
1262        return Error("Invalid INLINEASM record");
1263      unsigned ConstStrSize = Record[2+AsmStrSize];
1264      if (3+AsmStrSize+ConstStrSize > Record.size())
1265        return Error("Invalid INLINEASM record");
1266
1267      for (unsigned i = 0; i != AsmStrSize; ++i)
1268        AsmStr += (char)Record[2+i];
1269      for (unsigned i = 0; i != ConstStrSize; ++i)
1270        ConstrStr += (char)Record[3+AsmStrSize+i];
1271      PointerType *PTy = cast<PointerType>(CurTy);
1272      V = InlineAsm::get(cast<FunctionType>(PTy->getElementType()),
1273                         AsmStr, ConstrStr, HasSideEffects, IsAlignStack);
1274      break;
1275    }
1276    case bitc::CST_CODE_BLOCKADDRESS:{
1277      if (Record.size() < 3) return Error("Invalid CE_BLOCKADDRESS record");
1278      Type *FnTy = getTypeByID(Record[0]);
1279      if (FnTy == 0) return Error("Invalid CE_BLOCKADDRESS record");
1280      Function *Fn =
1281        dyn_cast_or_null<Function>(ValueList.getConstantFwdRef(Record[1],FnTy));
1282      if (Fn == 0) return Error("Invalid CE_BLOCKADDRESS record");
1283
1284      GlobalVariable *FwdRef = new GlobalVariable(*Fn->getParent(),
1285                                                  Type::getInt8Ty(Context),
1286                                            false, GlobalValue::InternalLinkage,
1287                                                  0, "");
1288      BlockAddrFwdRefs[Fn].push_back(std::make_pair(Record[2], FwdRef));
1289      V = FwdRef;
1290      break;
1291    }
1292    }
1293
1294    ValueList.AssignValue(V, NextCstNo);
1295    ++NextCstNo;
1296  }
1297
1298  if (NextCstNo != ValueList.size())
1299    return Error("Invalid constant reference!");
1300
1301  if (Stream.ReadBlockEnd())
1302    return Error("Error at end of constants block");
1303
1304  // Once all the constants have been read, go through and resolve forward
1305  // references.
1306  ValueList.ResolveConstantForwardRefs();
1307  return false;
1308}
1309
1310bool BitcodeReader::ParseUseLists() {
1311  if (Stream.EnterSubBlock(bitc::USELIST_BLOCK_ID))
1312    return Error("Malformed block record");
1313
1314  SmallVector<uint64_t, 64> Record;
1315
1316  // Read all the records.
1317  while (1) {
1318    unsigned Code = Stream.ReadCode();
1319    if (Code == bitc::END_BLOCK) {
1320      if (Stream.ReadBlockEnd())
1321        return Error("Error at end of use-list table block");
1322      return false;
1323    }
1324
1325    if (Code == bitc::ENTER_SUBBLOCK) {
1326      // No known subblocks, always skip them.
1327      Stream.ReadSubBlockID();
1328      if (Stream.SkipBlock())
1329        return Error("Malformed block record");
1330      continue;
1331    }
1332
1333    if (Code == bitc::DEFINE_ABBREV) {
1334      Stream.ReadAbbrevRecord();
1335      continue;
1336    }
1337
1338    // Read a use list record.
1339    Record.clear();
1340    switch (Stream.ReadRecord(Code, Record)) {
1341    default:  // Default behavior: unknown type.
1342      break;
1343    case bitc::USELIST_CODE_ENTRY: { // USELIST_CODE_ENTRY: TBD.
1344      unsigned RecordLength = Record.size();
1345      if (RecordLength < 1)
1346        return Error ("Invalid UseList reader!");
1347      UseListRecords.push_back(Record);
1348      break;
1349    }
1350    }
1351  }
1352}
1353
1354/// RememberAndSkipFunctionBody - When we see the block for a function body,
1355/// remember where it is and then skip it.  This lets us lazily deserialize the
1356/// functions.
1357bool BitcodeReader::RememberAndSkipFunctionBody() {
1358  // Get the function we are talking about.
1359  if (FunctionsWithBodies.empty())
1360    return Error("Insufficient function protos");
1361
1362  Function *Fn = FunctionsWithBodies.back();
1363  FunctionsWithBodies.pop_back();
1364
1365  // Save the current stream state.
1366  uint64_t CurBit = Stream.GetCurrentBitNo();
1367  DeferredFunctionInfo[Fn] = CurBit;
1368
1369  // Skip over the function block for now.
1370  if (Stream.SkipBlock())
1371    return Error("Malformed block record");
1372  return false;
1373}
1374
1375bool BitcodeReader::GlobalCleanup() {
1376  // Patch the initializers for globals and aliases up.
1377  ResolveGlobalAndAliasInits();
1378  if (!GlobalInits.empty() || !AliasInits.empty())
1379    return Error("Malformed global initializer set");
1380
1381  // Look for intrinsic functions which need to be upgraded at some point
1382  for (Module::iterator FI = TheModule->begin(), FE = TheModule->end();
1383       FI != FE; ++FI) {
1384    Function *NewFn;
1385    if (UpgradeIntrinsicFunction(FI, NewFn))
1386      UpgradedIntrinsics.push_back(std::make_pair(FI, NewFn));
1387  }
1388
1389  // Look for global variables which need to be renamed.
1390  for (Module::global_iterator
1391         GI = TheModule->global_begin(), GE = TheModule->global_end();
1392       GI != GE; ++GI)
1393    UpgradeGlobalVariable(GI);
1394  // Force deallocation of memory for these vectors to favor the client that
1395  // want lazy deserialization.
1396  std::vector<std::pair<GlobalVariable*, unsigned> >().swap(GlobalInits);
1397  std::vector<std::pair<GlobalAlias*, unsigned> >().swap(AliasInits);
1398  return false;
1399}
1400
1401bool BitcodeReader::ParseModule(bool Resume) {
1402  if (Resume)
1403    Stream.JumpToBit(NextUnreadBit);
1404  else if (Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
1405    return Error("Malformed block record");
1406
1407  SmallVector<uint64_t, 64> Record;
1408  std::vector<std::string> SectionTable;
1409  std::vector<std::string> GCTable;
1410
1411  // Read all the records for this module.
1412  while (!Stream.AtEndOfStream()) {
1413    unsigned Code = Stream.ReadCode();
1414    if (Code == bitc::END_BLOCK) {
1415      if (Stream.ReadBlockEnd())
1416        return Error("Error at end of module block");
1417
1418      return GlobalCleanup();
1419    }
1420
1421    if (Code == bitc::ENTER_SUBBLOCK) {
1422      switch (Stream.ReadSubBlockID()) {
1423      default:  // Skip unknown content.
1424        if (Stream.SkipBlock())
1425          return Error("Malformed block record");
1426        break;
1427      case bitc::BLOCKINFO_BLOCK_ID:
1428        if (Stream.ReadBlockInfoBlock())
1429          return Error("Malformed BlockInfoBlock");
1430        break;
1431      case bitc::PARAMATTR_BLOCK_ID:
1432        if (ParseAttributeBlock())
1433          return true;
1434        break;
1435      case bitc::TYPE_BLOCK_ID_NEW:
1436        if (ParseTypeTable())
1437          return true;
1438        break;
1439      case bitc::VALUE_SYMTAB_BLOCK_ID:
1440        if (ParseValueSymbolTable())
1441          return true;
1442        SeenValueSymbolTable = true;
1443        break;
1444      case bitc::CONSTANTS_BLOCK_ID:
1445        if (ParseConstants() || ResolveGlobalAndAliasInits())
1446          return true;
1447        break;
1448      case bitc::METADATA_BLOCK_ID:
1449        if (ParseMetadata())
1450          return true;
1451        break;
1452      case bitc::FUNCTION_BLOCK_ID:
1453        // If this is the first function body we've seen, reverse the
1454        // FunctionsWithBodies list.
1455        if (!SeenFirstFunctionBody) {
1456          std::reverse(FunctionsWithBodies.begin(), FunctionsWithBodies.end());
1457          if (GlobalCleanup())
1458            return true;
1459          SeenFirstFunctionBody = true;
1460        }
1461
1462        if (RememberAndSkipFunctionBody())
1463          return true;
1464        // For streaming bitcode, suspend parsing when we reach the function
1465        // bodies. Subsequent materialization calls will resume it when
1466        // necessary. For streaming, the function bodies must be at the end of
1467        // the bitcode. If the bitcode file is old, the symbol table will be
1468        // at the end instead and will not have been seen yet. In this case,
1469        // just finish the parse now.
1470        if (LazyStreamer && SeenValueSymbolTable) {
1471          NextUnreadBit = Stream.GetCurrentBitNo();
1472          return false;
1473        }
1474        break;
1475      case bitc::USELIST_BLOCK_ID:
1476        if (ParseUseLists())
1477          return true;
1478        break;
1479      }
1480      continue;
1481    }
1482
1483    if (Code == bitc::DEFINE_ABBREV) {
1484      Stream.ReadAbbrevRecord();
1485      continue;
1486    }
1487
1488    // Read a record.
1489    switch (Stream.ReadRecord(Code, Record)) {
1490    default: break;  // Default behavior, ignore unknown content.
1491    case bitc::MODULE_CODE_VERSION:  // VERSION: [version#]
1492      if (Record.size() < 1)
1493        return Error("Malformed MODULE_CODE_VERSION");
1494      // Only version #0 is supported so far.
1495      if (Record[0] != 0)
1496        return Error("Unknown bitstream version!");
1497      break;
1498    case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
1499      std::string S;
1500      if (ConvertToString(Record, 0, S))
1501        return Error("Invalid MODULE_CODE_TRIPLE record");
1502      TheModule->setTargetTriple(S);
1503      break;
1504    }
1505    case bitc::MODULE_CODE_DATALAYOUT: {  // DATALAYOUT: [strchr x N]
1506      std::string S;
1507      if (ConvertToString(Record, 0, S))
1508        return Error("Invalid MODULE_CODE_DATALAYOUT record");
1509      TheModule->setDataLayout(S);
1510      break;
1511    }
1512    case bitc::MODULE_CODE_ASM: {  // ASM: [strchr x N]
1513      std::string S;
1514      if (ConvertToString(Record, 0, S))
1515        return Error("Invalid MODULE_CODE_ASM record");
1516      TheModule->setModuleInlineAsm(S);
1517      break;
1518    }
1519    case bitc::MODULE_CODE_DEPLIB: {  // DEPLIB: [strchr x N]
1520      std::string S;
1521      if (ConvertToString(Record, 0, S))
1522        return Error("Invalid MODULE_CODE_DEPLIB record");
1523      TheModule->addLibrary(S);
1524      break;
1525    }
1526    case bitc::MODULE_CODE_SECTIONNAME: {  // SECTIONNAME: [strchr x N]
1527      std::string S;
1528      if (ConvertToString(Record, 0, S))
1529        return Error("Invalid MODULE_CODE_SECTIONNAME record");
1530      SectionTable.push_back(S);
1531      break;
1532    }
1533    case bitc::MODULE_CODE_GCNAME: {  // SECTIONNAME: [strchr x N]
1534      std::string S;
1535      if (ConvertToString(Record, 0, S))
1536        return Error("Invalid MODULE_CODE_GCNAME record");
1537      GCTable.push_back(S);
1538      break;
1539    }
1540    // GLOBALVAR: [pointer type, isconst, initid,
1541    //             linkage, alignment, section, visibility, threadlocal,
1542    //             unnamed_addr]
1543    case bitc::MODULE_CODE_GLOBALVAR: {
1544      if (Record.size() < 6)
1545        return Error("Invalid MODULE_CODE_GLOBALVAR record");
1546      Type *Ty = getTypeByID(Record[0]);
1547      if (!Ty) return Error("Invalid MODULE_CODE_GLOBALVAR record");
1548      if (!Ty->isPointerTy())
1549        return Error("Global not a pointer type!");
1550      unsigned AddressSpace = cast<PointerType>(Ty)->getAddressSpace();
1551      Ty = cast<PointerType>(Ty)->getElementType();
1552
1553      bool isConstant = Record[1];
1554      GlobalValue::LinkageTypes Linkage = GetDecodedLinkage(Record[3]);
1555      unsigned Alignment = (1 << Record[4]) >> 1;
1556      std::string Section;
1557      if (Record[5]) {
1558        if (Record[5]-1 >= SectionTable.size())
1559          return Error("Invalid section ID");
1560        Section = SectionTable[Record[5]-1];
1561      }
1562      GlobalValue::VisibilityTypes Visibility = GlobalValue::DefaultVisibility;
1563      if (Record.size() > 6)
1564        Visibility = GetDecodedVisibility(Record[6]);
1565      bool isThreadLocal = false;
1566      if (Record.size() > 7)
1567        isThreadLocal = Record[7];
1568
1569      bool UnnamedAddr = false;
1570      if (Record.size() > 8)
1571        UnnamedAddr = Record[8];
1572
1573      GlobalVariable *NewGV =
1574        new GlobalVariable(*TheModule, Ty, isConstant, Linkage, 0, "", 0,
1575                           isThreadLocal, AddressSpace);
1576      NewGV->setAlignment(Alignment);
1577      if (!Section.empty())
1578        NewGV->setSection(Section);
1579      NewGV->setVisibility(Visibility);
1580      NewGV->setThreadLocal(isThreadLocal);
1581      NewGV->setUnnamedAddr(UnnamedAddr);
1582
1583      ValueList.push_back(NewGV);
1584
1585      // Remember which value to use for the global initializer.
1586      if (unsigned InitID = Record[2])
1587        GlobalInits.push_back(std::make_pair(NewGV, InitID-1));
1588      break;
1589    }
1590    // FUNCTION:  [type, callingconv, isproto, linkage, paramattr,
1591    //             alignment, section, visibility, gc, unnamed_addr]
1592    case bitc::MODULE_CODE_FUNCTION: {
1593      if (Record.size() < 8)
1594        return Error("Invalid MODULE_CODE_FUNCTION record");
1595      Type *Ty = getTypeByID(Record[0]);
1596      if (!Ty) return Error("Invalid MODULE_CODE_FUNCTION record");
1597      if (!Ty->isPointerTy())
1598        return Error("Function not a pointer type!");
1599      FunctionType *FTy =
1600        dyn_cast<FunctionType>(cast<PointerType>(Ty)->getElementType());
1601      if (!FTy)
1602        return Error("Function not a pointer to function type!");
1603
1604      Function *Func = Function::Create(FTy, GlobalValue::ExternalLinkage,
1605                                        "", TheModule);
1606
1607      Func->setCallingConv(static_cast<CallingConv::ID>(Record[1]));
1608      bool isProto = Record[2];
1609      Func->setLinkage(GetDecodedLinkage(Record[3]));
1610      Func->setAttributes(getAttributes(Record[4]));
1611
1612      Func->setAlignment((1 << Record[5]) >> 1);
1613      if (Record[6]) {
1614        if (Record[6]-1 >= SectionTable.size())
1615          return Error("Invalid section ID");
1616        Func->setSection(SectionTable[Record[6]-1]);
1617      }
1618      Func->setVisibility(GetDecodedVisibility(Record[7]));
1619      if (Record.size() > 8 && Record[8]) {
1620        if (Record[8]-1 > GCTable.size())
1621          return Error("Invalid GC ID");
1622        Func->setGC(GCTable[Record[8]-1].c_str());
1623      }
1624      bool UnnamedAddr = false;
1625      if (Record.size() > 9)
1626        UnnamedAddr = Record[9];
1627      Func->setUnnamedAddr(UnnamedAddr);
1628      ValueList.push_back(Func);
1629
1630      // If this is a function with a body, remember the prototype we are
1631      // creating now, so that we can match up the body with them later.
1632      if (!isProto) {
1633        FunctionsWithBodies.push_back(Func);
1634        if (LazyStreamer) DeferredFunctionInfo[Func] = 0;
1635      }
1636      break;
1637    }
1638    // ALIAS: [alias type, aliasee val#, linkage]
1639    // ALIAS: [alias type, aliasee val#, linkage, visibility]
1640    case bitc::MODULE_CODE_ALIAS: {
1641      if (Record.size() < 3)
1642        return Error("Invalid MODULE_ALIAS record");
1643      Type *Ty = getTypeByID(Record[0]);
1644      if (!Ty) return Error("Invalid MODULE_ALIAS record");
1645      if (!Ty->isPointerTy())
1646        return Error("Function not a pointer type!");
1647
1648      GlobalAlias *NewGA = new GlobalAlias(Ty, GetDecodedLinkage(Record[2]),
1649                                           "", 0, TheModule);
1650      // Old bitcode files didn't have visibility field.
1651      if (Record.size() > 3)
1652        NewGA->setVisibility(GetDecodedVisibility(Record[3]));
1653      ValueList.push_back(NewGA);
1654      AliasInits.push_back(std::make_pair(NewGA, Record[1]));
1655      break;
1656    }
1657    /// MODULE_CODE_PURGEVALS: [numvals]
1658    case bitc::MODULE_CODE_PURGEVALS:
1659      // Trim down the value list to the specified size.
1660      if (Record.size() < 1 || Record[0] > ValueList.size())
1661        return Error("Invalid MODULE_PURGEVALS record");
1662      ValueList.shrinkTo(Record[0]);
1663      break;
1664    }
1665    Record.clear();
1666  }
1667
1668  return Error("Premature end of bitstream");
1669}
1670
1671bool BitcodeReader::ParseBitcodeInto(Module *M) {
1672  TheModule = 0;
1673
1674  if (InitStream()) return true;
1675
1676  // Sniff for the signature.
1677  if (Stream.Read(8) != 'B' ||
1678      Stream.Read(8) != 'C' ||
1679      Stream.Read(4) != 0x0 ||
1680      Stream.Read(4) != 0xC ||
1681      Stream.Read(4) != 0xE ||
1682      Stream.Read(4) != 0xD)
1683    return Error("Invalid bitcode signature");
1684
1685  // We expect a number of well-defined blocks, though we don't necessarily
1686  // need to understand them all.
1687  while (!Stream.AtEndOfStream()) {
1688    unsigned Code = Stream.ReadCode();
1689
1690    if (Code != bitc::ENTER_SUBBLOCK) {
1691
1692      // The ranlib in xcode 4 will align archive members by appending newlines
1693      // to the end of them. If this file size is a multiple of 4 but not 8, we
1694      // have to read and ignore these final 4 bytes :-(
1695      if (Stream.GetAbbrevIDWidth() == 2 && Code == 2 &&
1696          Stream.Read(6) == 2 && Stream.Read(24) == 0xa0a0a &&
1697	  Stream.AtEndOfStream())
1698        return false;
1699
1700      return Error("Invalid record at top-level");
1701    }
1702
1703    unsigned BlockID = Stream.ReadSubBlockID();
1704
1705    // We only know the MODULE subblock ID.
1706    switch (BlockID) {
1707    case bitc::BLOCKINFO_BLOCK_ID:
1708      if (Stream.ReadBlockInfoBlock())
1709        return Error("Malformed BlockInfoBlock");
1710      break;
1711    case bitc::MODULE_BLOCK_ID:
1712      // Reject multiple MODULE_BLOCK's in a single bitstream.
1713      if (TheModule)
1714        return Error("Multiple MODULE_BLOCKs in same stream");
1715      TheModule = M;
1716      if (ParseModule(false))
1717        return true;
1718      if (LazyStreamer) return false;
1719      break;
1720    default:
1721      if (Stream.SkipBlock())
1722        return Error("Malformed block record");
1723      break;
1724    }
1725  }
1726
1727  return false;
1728}
1729
1730bool BitcodeReader::ParseModuleTriple(std::string &Triple) {
1731  if (Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
1732    return Error("Malformed block record");
1733
1734  SmallVector<uint64_t, 64> Record;
1735
1736  // Read all the records for this module.
1737  while (!Stream.AtEndOfStream()) {
1738    unsigned Code = Stream.ReadCode();
1739    if (Code == bitc::END_BLOCK) {
1740      if (Stream.ReadBlockEnd())
1741        return Error("Error at end of module block");
1742
1743      return false;
1744    }
1745
1746    if (Code == bitc::ENTER_SUBBLOCK) {
1747      switch (Stream.ReadSubBlockID()) {
1748      default:  // Skip unknown content.
1749        if (Stream.SkipBlock())
1750          return Error("Malformed block record");
1751        break;
1752      }
1753      continue;
1754    }
1755
1756    if (Code == bitc::DEFINE_ABBREV) {
1757      Stream.ReadAbbrevRecord();
1758      continue;
1759    }
1760
1761    // Read a record.
1762    switch (Stream.ReadRecord(Code, Record)) {
1763    default: break;  // Default behavior, ignore unknown content.
1764    case bitc::MODULE_CODE_VERSION:  // VERSION: [version#]
1765      if (Record.size() < 1)
1766        return Error("Malformed MODULE_CODE_VERSION");
1767      // Only version #0 is supported so far.
1768      if (Record[0] != 0)
1769        return Error("Unknown bitstream version!");
1770      break;
1771    case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
1772      std::string S;
1773      if (ConvertToString(Record, 0, S))
1774        return Error("Invalid MODULE_CODE_TRIPLE record");
1775      Triple = S;
1776      break;
1777    }
1778    }
1779    Record.clear();
1780  }
1781
1782  return Error("Premature end of bitstream");
1783}
1784
1785bool BitcodeReader::ParseTriple(std::string &Triple) {
1786  if (InitStream()) return true;
1787
1788  // Sniff for the signature.
1789  if (Stream.Read(8) != 'B' ||
1790      Stream.Read(8) != 'C' ||
1791      Stream.Read(4) != 0x0 ||
1792      Stream.Read(4) != 0xC ||
1793      Stream.Read(4) != 0xE ||
1794      Stream.Read(4) != 0xD)
1795    return Error("Invalid bitcode signature");
1796
1797  // We expect a number of well-defined blocks, though we don't necessarily
1798  // need to understand them all.
1799  while (!Stream.AtEndOfStream()) {
1800    unsigned Code = Stream.ReadCode();
1801
1802    if (Code != bitc::ENTER_SUBBLOCK)
1803      return Error("Invalid record at top-level");
1804
1805    unsigned BlockID = Stream.ReadSubBlockID();
1806
1807    // We only know the MODULE subblock ID.
1808    switch (BlockID) {
1809    case bitc::MODULE_BLOCK_ID:
1810      if (ParseModuleTriple(Triple))
1811        return true;
1812      break;
1813    default:
1814      if (Stream.SkipBlock())
1815        return Error("Malformed block record");
1816      break;
1817    }
1818  }
1819
1820  return false;
1821}
1822
1823/// ParseMetadataAttachment - Parse metadata attachments.
1824bool BitcodeReader::ParseMetadataAttachment() {
1825  if (Stream.EnterSubBlock(bitc::METADATA_ATTACHMENT_ID))
1826    return Error("Malformed block record");
1827
1828  SmallVector<uint64_t, 64> Record;
1829  while(1) {
1830    unsigned Code = Stream.ReadCode();
1831    if (Code == bitc::END_BLOCK) {
1832      if (Stream.ReadBlockEnd())
1833        return Error("Error at end of PARAMATTR block");
1834      break;
1835    }
1836    if (Code == bitc::DEFINE_ABBREV) {
1837      Stream.ReadAbbrevRecord();
1838      continue;
1839    }
1840    // Read a metadata attachment record.
1841    Record.clear();
1842    switch (Stream.ReadRecord(Code, Record)) {
1843    default:  // Default behavior: ignore.
1844      break;
1845    case bitc::METADATA_ATTACHMENT: {
1846      unsigned RecordLength = Record.size();
1847      if (Record.empty() || (RecordLength - 1) % 2 == 1)
1848        return Error ("Invalid METADATA_ATTACHMENT reader!");
1849      Instruction *Inst = InstructionList[Record[0]];
1850      for (unsigned i = 1; i != RecordLength; i = i+2) {
1851        unsigned Kind = Record[i];
1852        DenseMap<unsigned, unsigned>::iterator I =
1853          MDKindMap.find(Kind);
1854        if (I == MDKindMap.end())
1855          return Error("Invalid metadata kind ID");
1856        Value *Node = MDValueList.getValueFwdRef(Record[i+1]);
1857        Inst->setMetadata(I->second, cast<MDNode>(Node));
1858      }
1859      break;
1860    }
1861    }
1862  }
1863  return false;
1864}
1865
1866/// ParseFunctionBody - Lazily parse the specified function body block.
1867bool BitcodeReader::ParseFunctionBody(Function *F) {
1868  if (Stream.EnterSubBlock(bitc::FUNCTION_BLOCK_ID))
1869    return Error("Malformed block record");
1870
1871  InstructionList.clear();
1872  unsigned ModuleValueListSize = ValueList.size();
1873  unsigned ModuleMDValueListSize = MDValueList.size();
1874
1875  // Add all the function arguments to the value table.
1876  for(Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
1877    ValueList.push_back(I);
1878
1879  unsigned NextValueNo = ValueList.size();
1880  BasicBlock *CurBB = 0;
1881  unsigned CurBBNo = 0;
1882
1883  DebugLoc LastLoc;
1884
1885  // Read all the records.
1886  SmallVector<uint64_t, 64> Record;
1887  while (1) {
1888    unsigned Code = Stream.ReadCode();
1889    if (Code == bitc::END_BLOCK) {
1890      if (Stream.ReadBlockEnd())
1891        return Error("Error at end of function block");
1892      break;
1893    }
1894
1895    if (Code == bitc::ENTER_SUBBLOCK) {
1896      switch (Stream.ReadSubBlockID()) {
1897      default:  // Skip unknown content.
1898        if (Stream.SkipBlock())
1899          return Error("Malformed block record");
1900        break;
1901      case bitc::CONSTANTS_BLOCK_ID:
1902        if (ParseConstants()) return true;
1903        NextValueNo = ValueList.size();
1904        break;
1905      case bitc::VALUE_SYMTAB_BLOCK_ID:
1906        if (ParseValueSymbolTable()) return true;
1907        break;
1908      case bitc::METADATA_ATTACHMENT_ID:
1909        if (ParseMetadataAttachment()) return true;
1910        break;
1911      case bitc::METADATA_BLOCK_ID:
1912        if (ParseMetadata()) return true;
1913        break;
1914      }
1915      continue;
1916    }
1917
1918    if (Code == bitc::DEFINE_ABBREV) {
1919      Stream.ReadAbbrevRecord();
1920      continue;
1921    }
1922
1923    // Read a record.
1924    Record.clear();
1925    Instruction *I = 0;
1926    unsigned BitCode = Stream.ReadRecord(Code, Record);
1927    switch (BitCode) {
1928    default: // Default behavior: reject
1929      return Error("Unknown instruction");
1930    case bitc::FUNC_CODE_DECLAREBLOCKS:     // DECLAREBLOCKS: [nblocks]
1931      if (Record.size() < 1 || Record[0] == 0)
1932        return Error("Invalid DECLAREBLOCKS record");
1933      // Create all the basic blocks for the function.
1934      FunctionBBs.resize(Record[0]);
1935      for (unsigned i = 0, e = FunctionBBs.size(); i != e; ++i)
1936        FunctionBBs[i] = BasicBlock::Create(Context, "", F);
1937      CurBB = FunctionBBs[0];
1938      continue;
1939
1940    case bitc::FUNC_CODE_DEBUG_LOC_AGAIN:  // DEBUG_LOC_AGAIN
1941      // This record indicates that the last instruction is at the same
1942      // location as the previous instruction with a location.
1943      I = 0;
1944
1945      // Get the last instruction emitted.
1946      if (CurBB && !CurBB->empty())
1947        I = &CurBB->back();
1948      else if (CurBBNo && FunctionBBs[CurBBNo-1] &&
1949               !FunctionBBs[CurBBNo-1]->empty())
1950        I = &FunctionBBs[CurBBNo-1]->back();
1951
1952      if (I == 0) return Error("Invalid DEBUG_LOC_AGAIN record");
1953      I->setDebugLoc(LastLoc);
1954      I = 0;
1955      continue;
1956
1957    case bitc::FUNC_CODE_DEBUG_LOC: {      // DEBUG_LOC: [line, col, scope, ia]
1958      I = 0;     // Get the last instruction emitted.
1959      if (CurBB && !CurBB->empty())
1960        I = &CurBB->back();
1961      else if (CurBBNo && FunctionBBs[CurBBNo-1] &&
1962               !FunctionBBs[CurBBNo-1]->empty())
1963        I = &FunctionBBs[CurBBNo-1]->back();
1964      if (I == 0 || Record.size() < 4)
1965        return Error("Invalid FUNC_CODE_DEBUG_LOC record");
1966
1967      unsigned Line = Record[0], Col = Record[1];
1968      unsigned ScopeID = Record[2], IAID = Record[3];
1969
1970      MDNode *Scope = 0, *IA = 0;
1971      if (ScopeID) Scope = cast<MDNode>(MDValueList.getValueFwdRef(ScopeID-1));
1972      if (IAID)    IA = cast<MDNode>(MDValueList.getValueFwdRef(IAID-1));
1973      LastLoc = DebugLoc::get(Line, Col, Scope, IA);
1974      I->setDebugLoc(LastLoc);
1975      I = 0;
1976      continue;
1977    }
1978
1979    case bitc::FUNC_CODE_INST_BINOP: {    // BINOP: [opval, ty, opval, opcode]
1980      unsigned OpNum = 0;
1981      Value *LHS, *RHS;
1982      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
1983          getValue(Record, OpNum, LHS->getType(), RHS) ||
1984          OpNum+1 > Record.size())
1985        return Error("Invalid BINOP record");
1986
1987      int Opc = GetDecodedBinaryOpcode(Record[OpNum++], LHS->getType());
1988      if (Opc == -1) return Error("Invalid BINOP record");
1989      I = BinaryOperator::Create((Instruction::BinaryOps)Opc, LHS, RHS);
1990      InstructionList.push_back(I);
1991      if (OpNum < Record.size()) {
1992        if (Opc == Instruction::Add ||
1993            Opc == Instruction::Sub ||
1994            Opc == Instruction::Mul ||
1995            Opc == Instruction::Shl) {
1996          if (Record[OpNum] & (1 << bitc::OBO_NO_SIGNED_WRAP))
1997            cast<BinaryOperator>(I)->setHasNoSignedWrap(true);
1998          if (Record[OpNum] & (1 << bitc::OBO_NO_UNSIGNED_WRAP))
1999            cast<BinaryOperator>(I)->setHasNoUnsignedWrap(true);
2000        } else if (Opc == Instruction::SDiv ||
2001                   Opc == Instruction::UDiv ||
2002                   Opc == Instruction::LShr ||
2003                   Opc == Instruction::AShr) {
2004          if (Record[OpNum] & (1 << bitc::PEO_EXACT))
2005            cast<BinaryOperator>(I)->setIsExact(true);
2006        }
2007      }
2008      break;
2009    }
2010    case bitc::FUNC_CODE_INST_CAST: {    // CAST: [opval, opty, destty, castopc]
2011      unsigned OpNum = 0;
2012      Value *Op;
2013      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
2014          OpNum+2 != Record.size())
2015        return Error("Invalid CAST record");
2016
2017      Type *ResTy = getTypeByID(Record[OpNum]);
2018      int Opc = GetDecodedCastOpcode(Record[OpNum+1]);
2019      if (Opc == -1 || ResTy == 0)
2020        return Error("Invalid CAST record");
2021      I = CastInst::Create((Instruction::CastOps)Opc, Op, ResTy);
2022      InstructionList.push_back(I);
2023      break;
2024    }
2025    case bitc::FUNC_CODE_INST_INBOUNDS_GEP:
2026    case bitc::FUNC_CODE_INST_GEP: { // GEP: [n x operands]
2027      unsigned OpNum = 0;
2028      Value *BasePtr;
2029      if (getValueTypePair(Record, OpNum, NextValueNo, BasePtr))
2030        return Error("Invalid GEP record");
2031
2032      SmallVector<Value*, 16> GEPIdx;
2033      while (OpNum != Record.size()) {
2034        Value *Op;
2035        if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2036          return Error("Invalid GEP record");
2037        GEPIdx.push_back(Op);
2038      }
2039
2040      I = GetElementPtrInst::Create(BasePtr, GEPIdx);
2041      InstructionList.push_back(I);
2042      if (BitCode == bitc::FUNC_CODE_INST_INBOUNDS_GEP)
2043        cast<GetElementPtrInst>(I)->setIsInBounds(true);
2044      break;
2045    }
2046
2047    case bitc::FUNC_CODE_INST_EXTRACTVAL: {
2048                                       // EXTRACTVAL: [opty, opval, n x indices]
2049      unsigned OpNum = 0;
2050      Value *Agg;
2051      if (getValueTypePair(Record, OpNum, NextValueNo, Agg))
2052        return Error("Invalid EXTRACTVAL record");
2053
2054      SmallVector<unsigned, 4> EXTRACTVALIdx;
2055      for (unsigned RecSize = Record.size();
2056           OpNum != RecSize; ++OpNum) {
2057        uint64_t Index = Record[OpNum];
2058        if ((unsigned)Index != Index)
2059          return Error("Invalid EXTRACTVAL index");
2060        EXTRACTVALIdx.push_back((unsigned)Index);
2061      }
2062
2063      I = ExtractValueInst::Create(Agg, EXTRACTVALIdx);
2064      InstructionList.push_back(I);
2065      break;
2066    }
2067
2068    case bitc::FUNC_CODE_INST_INSERTVAL: {
2069                           // INSERTVAL: [opty, opval, opty, opval, n x indices]
2070      unsigned OpNum = 0;
2071      Value *Agg;
2072      if (getValueTypePair(Record, OpNum, NextValueNo, Agg))
2073        return Error("Invalid INSERTVAL record");
2074      Value *Val;
2075      if (getValueTypePair(Record, OpNum, NextValueNo, Val))
2076        return Error("Invalid INSERTVAL record");
2077
2078      SmallVector<unsigned, 4> INSERTVALIdx;
2079      for (unsigned RecSize = Record.size();
2080           OpNum != RecSize; ++OpNum) {
2081        uint64_t Index = Record[OpNum];
2082        if ((unsigned)Index != Index)
2083          return Error("Invalid INSERTVAL index");
2084        INSERTVALIdx.push_back((unsigned)Index);
2085      }
2086
2087      I = InsertValueInst::Create(Agg, Val, INSERTVALIdx);
2088      InstructionList.push_back(I);
2089      break;
2090    }
2091
2092    case bitc::FUNC_CODE_INST_SELECT: { // SELECT: [opval, ty, opval, opval]
2093      // obsolete form of select
2094      // handles select i1 ... in old bitcode
2095      unsigned OpNum = 0;
2096      Value *TrueVal, *FalseVal, *Cond;
2097      if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
2098          getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
2099          getValue(Record, OpNum, Type::getInt1Ty(Context), Cond))
2100        return Error("Invalid SELECT record");
2101
2102      I = SelectInst::Create(Cond, TrueVal, FalseVal);
2103      InstructionList.push_back(I);
2104      break;
2105    }
2106
2107    case bitc::FUNC_CODE_INST_VSELECT: {// VSELECT: [ty,opval,opval,predty,pred]
2108      // new form of select
2109      // handles select i1 or select [N x i1]
2110      unsigned OpNum = 0;
2111      Value *TrueVal, *FalseVal, *Cond;
2112      if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
2113          getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
2114          getValueTypePair(Record, OpNum, NextValueNo, Cond))
2115        return Error("Invalid SELECT record");
2116
2117      // select condition can be either i1 or [N x i1]
2118      if (VectorType* vector_type =
2119          dyn_cast<VectorType>(Cond->getType())) {
2120        // expect <n x i1>
2121        if (vector_type->getElementType() != Type::getInt1Ty(Context))
2122          return Error("Invalid SELECT condition type");
2123      } else {
2124        // expect i1
2125        if (Cond->getType() != Type::getInt1Ty(Context))
2126          return Error("Invalid SELECT condition type");
2127      }
2128
2129      I = SelectInst::Create(Cond, TrueVal, FalseVal);
2130      InstructionList.push_back(I);
2131      break;
2132    }
2133
2134    case bitc::FUNC_CODE_INST_EXTRACTELT: { // EXTRACTELT: [opty, opval, opval]
2135      unsigned OpNum = 0;
2136      Value *Vec, *Idx;
2137      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
2138          getValue(Record, OpNum, Type::getInt32Ty(Context), Idx))
2139        return Error("Invalid EXTRACTELT record");
2140      I = ExtractElementInst::Create(Vec, Idx);
2141      InstructionList.push_back(I);
2142      break;
2143    }
2144
2145    case bitc::FUNC_CODE_INST_INSERTELT: { // INSERTELT: [ty, opval,opval,opval]
2146      unsigned OpNum = 0;
2147      Value *Vec, *Elt, *Idx;
2148      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
2149          getValue(Record, OpNum,
2150                   cast<VectorType>(Vec->getType())->getElementType(), Elt) ||
2151          getValue(Record, OpNum, Type::getInt32Ty(Context), Idx))
2152        return Error("Invalid INSERTELT record");
2153      I = InsertElementInst::Create(Vec, Elt, Idx);
2154      InstructionList.push_back(I);
2155      break;
2156    }
2157
2158    case bitc::FUNC_CODE_INST_SHUFFLEVEC: {// SHUFFLEVEC: [opval,ty,opval,opval]
2159      unsigned OpNum = 0;
2160      Value *Vec1, *Vec2, *Mask;
2161      if (getValueTypePair(Record, OpNum, NextValueNo, Vec1) ||
2162          getValue(Record, OpNum, Vec1->getType(), Vec2))
2163        return Error("Invalid SHUFFLEVEC record");
2164
2165      if (getValueTypePair(Record, OpNum, NextValueNo, Mask))
2166        return Error("Invalid SHUFFLEVEC record");
2167      I = new ShuffleVectorInst(Vec1, Vec2, Mask);
2168      InstructionList.push_back(I);
2169      break;
2170    }
2171
2172    case bitc::FUNC_CODE_INST_CMP:   // CMP: [opty, opval, opval, pred]
2173      // Old form of ICmp/FCmp returning bool
2174      // Existed to differentiate between icmp/fcmp and vicmp/vfcmp which were
2175      // both legal on vectors but had different behaviour.
2176    case bitc::FUNC_CODE_INST_CMP2: { // CMP2: [opty, opval, opval, pred]
2177      // FCmp/ICmp returning bool or vector of bool
2178
2179      unsigned OpNum = 0;
2180      Value *LHS, *RHS;
2181      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
2182          getValue(Record, OpNum, LHS->getType(), RHS) ||
2183          OpNum+1 != Record.size())
2184        return Error("Invalid CMP record");
2185
2186      if (LHS->getType()->isFPOrFPVectorTy())
2187        I = new FCmpInst((FCmpInst::Predicate)Record[OpNum], LHS, RHS);
2188      else
2189        I = new ICmpInst((ICmpInst::Predicate)Record[OpNum], LHS, RHS);
2190      InstructionList.push_back(I);
2191      break;
2192    }
2193
2194    case bitc::FUNC_CODE_INST_RET: // RET: [opty,opval<optional>]
2195      {
2196        unsigned Size = Record.size();
2197        if (Size == 0) {
2198          I = ReturnInst::Create(Context);
2199          InstructionList.push_back(I);
2200          break;
2201        }
2202
2203        unsigned OpNum = 0;
2204        Value *Op = NULL;
2205        if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2206          return Error("Invalid RET record");
2207        if (OpNum != Record.size())
2208          return Error("Invalid RET record");
2209
2210        I = ReturnInst::Create(Context, Op);
2211        InstructionList.push_back(I);
2212        break;
2213      }
2214    case bitc::FUNC_CODE_INST_BR: { // BR: [bb#, bb#, opval] or [bb#]
2215      if (Record.size() != 1 && Record.size() != 3)
2216        return Error("Invalid BR record");
2217      BasicBlock *TrueDest = getBasicBlock(Record[0]);
2218      if (TrueDest == 0)
2219        return Error("Invalid BR record");
2220
2221      if (Record.size() == 1) {
2222        I = BranchInst::Create(TrueDest);
2223        InstructionList.push_back(I);
2224      }
2225      else {
2226        BasicBlock *FalseDest = getBasicBlock(Record[1]);
2227        Value *Cond = getFnValueByID(Record[2], Type::getInt1Ty(Context));
2228        if (FalseDest == 0 || Cond == 0)
2229          return Error("Invalid BR record");
2230        I = BranchInst::Create(TrueDest, FalseDest, Cond);
2231        InstructionList.push_back(I);
2232      }
2233      break;
2234    }
2235    case bitc::FUNC_CODE_INST_SWITCH: { // SWITCH: [opty, op0, op1, ...]
2236      // Check magic
2237      if ((Record[0] >> 16) == SWITCH_INST_MAGIC) {
2238        // New SwitchInst format with case ranges.
2239
2240        Type *OpTy = getTypeByID(Record[1]);
2241        unsigned ValueBitWidth = cast<IntegerType>(OpTy)->getBitWidth();
2242
2243        Value *Cond = getFnValueByID(Record[2], OpTy);
2244        BasicBlock *Default = getBasicBlock(Record[3]);
2245        if (OpTy == 0 || Cond == 0 || Default == 0)
2246          return Error("Invalid SWITCH record");
2247
2248        unsigned NumCases = Record[4];
2249
2250        SwitchInst *SI = SwitchInst::Create(Cond, Default, NumCases);
2251        InstructionList.push_back(SI);
2252
2253        unsigned CurIdx = 5;
2254        for (unsigned i = 0; i != NumCases; ++i) {
2255          CRSBuilder CaseBuilder;
2256          unsigned NumItems = Record[CurIdx++];
2257          for (unsigned ci = 0; ci != NumItems; ++ci) {
2258            bool isSingleNumber = Record[CurIdx++];
2259
2260            APInt Low;
2261            unsigned ActiveWords = 1;
2262            if (ValueBitWidth > 64)
2263              ActiveWords = Record[CurIdx++];
2264            Low = ReadWideAPInt(&Record[CurIdx], ActiveWords, ValueBitWidth);
2265            CurIdx += ActiveWords;
2266
2267            if (!isSingleNumber) {
2268              ActiveWords = 1;
2269              if (ValueBitWidth > 64)
2270                ActiveWords = Record[CurIdx++];
2271              APInt High =
2272                  ReadWideAPInt(&Record[CurIdx], ActiveWords, ValueBitWidth);
2273              CaseBuilder.add(cast<ConstantInt>(ConstantInt::get(OpTy, Low)),
2274                              cast<ConstantInt>(ConstantInt::get(OpTy, High)));
2275              CurIdx += ActiveWords;
2276            } else
2277              CaseBuilder.add(cast<ConstantInt>(ConstantInt::get(OpTy, Low)));
2278          }
2279          BasicBlock *DestBB = getBasicBlock(Record[CurIdx++]);
2280          ConstantRangesSet Case = CaseBuilder.getCase();
2281          SI->addCase(Case, DestBB);
2282        }
2283        uint16_t Hash = SI->Hash();
2284        if (Hash != (Record[0] & 0xFFFF))
2285          return Error("Invalid SWITCH record");
2286        I = SI;
2287        break;
2288      }
2289
2290      // Old SwitchInst format without case ranges.
2291
2292      if (Record.size() < 3 || (Record.size() & 1) == 0)
2293        return Error("Invalid SWITCH record");
2294      Type *OpTy = getTypeByID(Record[0]);
2295      Value *Cond = getFnValueByID(Record[1], OpTy);
2296      BasicBlock *Default = getBasicBlock(Record[2]);
2297      if (OpTy == 0 || Cond == 0 || Default == 0)
2298        return Error("Invalid SWITCH record");
2299      unsigned NumCases = (Record.size()-3)/2;
2300      SwitchInst *SI = SwitchInst::Create(Cond, Default, NumCases);
2301      InstructionList.push_back(SI);
2302      for (unsigned i = 0, e = NumCases; i != e; ++i) {
2303        ConstantInt *CaseVal =
2304          dyn_cast_or_null<ConstantInt>(getFnValueByID(Record[3+i*2], OpTy));
2305        BasicBlock *DestBB = getBasicBlock(Record[1+3+i*2]);
2306        if (CaseVal == 0 || DestBB == 0) {
2307          delete SI;
2308          return Error("Invalid SWITCH record!");
2309        }
2310        SI->addCase(CaseVal, DestBB);
2311      }
2312      I = SI;
2313      break;
2314    }
2315    case bitc::FUNC_CODE_INST_INDIRECTBR: { // INDIRECTBR: [opty, op0, op1, ...]
2316      if (Record.size() < 2)
2317        return Error("Invalid INDIRECTBR record");
2318      Type *OpTy = getTypeByID(Record[0]);
2319      Value *Address = getFnValueByID(Record[1], OpTy);
2320      if (OpTy == 0 || Address == 0)
2321        return Error("Invalid INDIRECTBR record");
2322      unsigned NumDests = Record.size()-2;
2323      IndirectBrInst *IBI = IndirectBrInst::Create(Address, NumDests);
2324      InstructionList.push_back(IBI);
2325      for (unsigned i = 0, e = NumDests; i != e; ++i) {
2326        if (BasicBlock *DestBB = getBasicBlock(Record[2+i])) {
2327          IBI->addDestination(DestBB);
2328        } else {
2329          delete IBI;
2330          return Error("Invalid INDIRECTBR record!");
2331        }
2332      }
2333      I = IBI;
2334      break;
2335    }
2336
2337    case bitc::FUNC_CODE_INST_INVOKE: {
2338      // INVOKE: [attrs, cc, normBB, unwindBB, fnty, op0,op1,op2, ...]
2339      if (Record.size() < 4) return Error("Invalid INVOKE record");
2340      AttrListPtr PAL = getAttributes(Record[0]);
2341      unsigned CCInfo = Record[1];
2342      BasicBlock *NormalBB = getBasicBlock(Record[2]);
2343      BasicBlock *UnwindBB = getBasicBlock(Record[3]);
2344
2345      unsigned OpNum = 4;
2346      Value *Callee;
2347      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
2348        return Error("Invalid INVOKE record");
2349
2350      PointerType *CalleeTy = dyn_cast<PointerType>(Callee->getType());
2351      FunctionType *FTy = !CalleeTy ? 0 :
2352        dyn_cast<FunctionType>(CalleeTy->getElementType());
2353
2354      // Check that the right number of fixed parameters are here.
2355      if (FTy == 0 || NormalBB == 0 || UnwindBB == 0 ||
2356          Record.size() < OpNum+FTy->getNumParams())
2357        return Error("Invalid INVOKE record");
2358
2359      SmallVector<Value*, 16> Ops;
2360      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
2361        Ops.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
2362        if (Ops.back() == 0) return Error("Invalid INVOKE record");
2363      }
2364
2365      if (!FTy->isVarArg()) {
2366        if (Record.size() != OpNum)
2367          return Error("Invalid INVOKE record");
2368      } else {
2369        // Read type/value pairs for varargs params.
2370        while (OpNum != Record.size()) {
2371          Value *Op;
2372          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2373            return Error("Invalid INVOKE record");
2374          Ops.push_back(Op);
2375        }
2376      }
2377
2378      I = InvokeInst::Create(Callee, NormalBB, UnwindBB, Ops);
2379      InstructionList.push_back(I);
2380      cast<InvokeInst>(I)->setCallingConv(
2381        static_cast<CallingConv::ID>(CCInfo));
2382      cast<InvokeInst>(I)->setAttributes(PAL);
2383      break;
2384    }
2385    case bitc::FUNC_CODE_INST_RESUME: { // RESUME: [opval]
2386      unsigned Idx = 0;
2387      Value *Val = 0;
2388      if (getValueTypePair(Record, Idx, NextValueNo, Val))
2389        return Error("Invalid RESUME record");
2390      I = ResumeInst::Create(Val);
2391      InstructionList.push_back(I);
2392      break;
2393    }
2394    case bitc::FUNC_CODE_INST_UNREACHABLE: // UNREACHABLE
2395      I = new UnreachableInst(Context);
2396      InstructionList.push_back(I);
2397      break;
2398    case bitc::FUNC_CODE_INST_PHI: { // PHI: [ty, val0,bb0, ...]
2399      if (Record.size() < 1 || ((Record.size()-1)&1))
2400        return Error("Invalid PHI record");
2401      Type *Ty = getTypeByID(Record[0]);
2402      if (!Ty) return Error("Invalid PHI record");
2403
2404      PHINode *PN = PHINode::Create(Ty, (Record.size()-1)/2);
2405      InstructionList.push_back(PN);
2406
2407      for (unsigned i = 0, e = Record.size()-1; i != e; i += 2) {
2408        Value *V = getFnValueByID(Record[1+i], Ty);
2409        BasicBlock *BB = getBasicBlock(Record[2+i]);
2410        if (!V || !BB) return Error("Invalid PHI record");
2411        PN->addIncoming(V, BB);
2412      }
2413      I = PN;
2414      break;
2415    }
2416
2417    case bitc::FUNC_CODE_INST_LANDINGPAD: {
2418      // LANDINGPAD: [ty, val, val, num, (id0,val0 ...)?]
2419      unsigned Idx = 0;
2420      if (Record.size() < 4)
2421        return Error("Invalid LANDINGPAD record");
2422      Type *Ty = getTypeByID(Record[Idx++]);
2423      if (!Ty) return Error("Invalid LANDINGPAD record");
2424      Value *PersFn = 0;
2425      if (getValueTypePair(Record, Idx, NextValueNo, PersFn))
2426        return Error("Invalid LANDINGPAD record");
2427
2428      bool IsCleanup = !!Record[Idx++];
2429      unsigned NumClauses = Record[Idx++];
2430      LandingPadInst *LP = LandingPadInst::Create(Ty, PersFn, NumClauses);
2431      LP->setCleanup(IsCleanup);
2432      for (unsigned J = 0; J != NumClauses; ++J) {
2433        LandingPadInst::ClauseType CT =
2434          LandingPadInst::ClauseType(Record[Idx++]); (void)CT;
2435        Value *Val;
2436
2437        if (getValueTypePair(Record, Idx, NextValueNo, Val)) {
2438          delete LP;
2439          return Error("Invalid LANDINGPAD record");
2440        }
2441
2442        assert((CT != LandingPadInst::Catch ||
2443                !isa<ArrayType>(Val->getType())) &&
2444               "Catch clause has a invalid type!");
2445        assert((CT != LandingPadInst::Filter ||
2446                isa<ArrayType>(Val->getType())) &&
2447               "Filter clause has invalid type!");
2448        LP->addClause(Val);
2449      }
2450
2451      I = LP;
2452      InstructionList.push_back(I);
2453      break;
2454    }
2455
2456    case bitc::FUNC_CODE_INST_ALLOCA: { // ALLOCA: [instty, opty, op, align]
2457      if (Record.size() != 4)
2458        return Error("Invalid ALLOCA record");
2459      PointerType *Ty =
2460        dyn_cast_or_null<PointerType>(getTypeByID(Record[0]));
2461      Type *OpTy = getTypeByID(Record[1]);
2462      Value *Size = getFnValueByID(Record[2], OpTy);
2463      unsigned Align = Record[3];
2464      if (!Ty || !Size) return Error("Invalid ALLOCA record");
2465      I = new AllocaInst(Ty->getElementType(), Size, (1 << Align) >> 1);
2466      InstructionList.push_back(I);
2467      break;
2468    }
2469    case bitc::FUNC_CODE_INST_LOAD: { // LOAD: [opty, op, align, vol]
2470      unsigned OpNum = 0;
2471      Value *Op;
2472      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
2473          OpNum+2 != Record.size())
2474        return Error("Invalid LOAD record");
2475
2476      I = new LoadInst(Op, "", Record[OpNum+1], (1 << Record[OpNum]) >> 1);
2477      InstructionList.push_back(I);
2478      break;
2479    }
2480    case bitc::FUNC_CODE_INST_LOADATOMIC: {
2481       // LOADATOMIC: [opty, op, align, vol, ordering, synchscope]
2482      unsigned OpNum = 0;
2483      Value *Op;
2484      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
2485          OpNum+4 != Record.size())
2486        return Error("Invalid LOADATOMIC record");
2487
2488
2489      AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]);
2490      if (Ordering == NotAtomic || Ordering == Release ||
2491          Ordering == AcquireRelease)
2492        return Error("Invalid LOADATOMIC record");
2493      if (Ordering != NotAtomic && Record[OpNum] == 0)
2494        return Error("Invalid LOADATOMIC record");
2495      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+3]);
2496
2497      I = new LoadInst(Op, "", Record[OpNum+1], (1 << Record[OpNum]) >> 1,
2498                       Ordering, SynchScope);
2499      InstructionList.push_back(I);
2500      break;
2501    }
2502    case bitc::FUNC_CODE_INST_STORE: { // STORE2:[ptrty, ptr, val, align, vol]
2503      unsigned OpNum = 0;
2504      Value *Val, *Ptr;
2505      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
2506          getValue(Record, OpNum,
2507                    cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
2508          OpNum+2 != Record.size())
2509        return Error("Invalid STORE record");
2510
2511      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1);
2512      InstructionList.push_back(I);
2513      break;
2514    }
2515    case bitc::FUNC_CODE_INST_STOREATOMIC: {
2516      // STOREATOMIC: [ptrty, ptr, val, align, vol, ordering, synchscope]
2517      unsigned OpNum = 0;
2518      Value *Val, *Ptr;
2519      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
2520          getValue(Record, OpNum,
2521                    cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
2522          OpNum+4 != Record.size())
2523        return Error("Invalid STOREATOMIC record");
2524
2525      AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]);
2526      if (Ordering == NotAtomic || Ordering == Acquire ||
2527          Ordering == AcquireRelease)
2528        return Error("Invalid STOREATOMIC record");
2529      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+3]);
2530      if (Ordering != NotAtomic && Record[OpNum] == 0)
2531        return Error("Invalid STOREATOMIC record");
2532
2533      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1,
2534                        Ordering, SynchScope);
2535      InstructionList.push_back(I);
2536      break;
2537    }
2538    case bitc::FUNC_CODE_INST_CMPXCHG: {
2539      // CMPXCHG:[ptrty, ptr, cmp, new, vol, ordering, synchscope]
2540      unsigned OpNum = 0;
2541      Value *Ptr, *Cmp, *New;
2542      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
2543          getValue(Record, OpNum,
2544                    cast<PointerType>(Ptr->getType())->getElementType(), Cmp) ||
2545          getValue(Record, OpNum,
2546                    cast<PointerType>(Ptr->getType())->getElementType(), New) ||
2547          OpNum+3 != Record.size())
2548        return Error("Invalid CMPXCHG record");
2549      AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+1]);
2550      if (Ordering == NotAtomic || Ordering == Unordered)
2551        return Error("Invalid CMPXCHG record");
2552      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+2]);
2553      I = new AtomicCmpXchgInst(Ptr, Cmp, New, Ordering, SynchScope);
2554      cast<AtomicCmpXchgInst>(I)->setVolatile(Record[OpNum]);
2555      InstructionList.push_back(I);
2556      break;
2557    }
2558    case bitc::FUNC_CODE_INST_ATOMICRMW: {
2559      // ATOMICRMW:[ptrty, ptr, val, op, vol, ordering, synchscope]
2560      unsigned OpNum = 0;
2561      Value *Ptr, *Val;
2562      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
2563          getValue(Record, OpNum,
2564                    cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
2565          OpNum+4 != Record.size())
2566        return Error("Invalid ATOMICRMW record");
2567      AtomicRMWInst::BinOp Operation = GetDecodedRMWOperation(Record[OpNum]);
2568      if (Operation < AtomicRMWInst::FIRST_BINOP ||
2569          Operation > AtomicRMWInst::LAST_BINOP)
2570        return Error("Invalid ATOMICRMW record");
2571      AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]);
2572      if (Ordering == NotAtomic || Ordering == Unordered)
2573        return Error("Invalid ATOMICRMW record");
2574      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+3]);
2575      I = new AtomicRMWInst(Operation, Ptr, Val, Ordering, SynchScope);
2576      cast<AtomicRMWInst>(I)->setVolatile(Record[OpNum+1]);
2577      InstructionList.push_back(I);
2578      break;
2579    }
2580    case bitc::FUNC_CODE_INST_FENCE: { // FENCE:[ordering, synchscope]
2581      if (2 != Record.size())
2582        return Error("Invalid FENCE record");
2583      AtomicOrdering Ordering = GetDecodedOrdering(Record[0]);
2584      if (Ordering == NotAtomic || Ordering == Unordered ||
2585          Ordering == Monotonic)
2586        return Error("Invalid FENCE record");
2587      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[1]);
2588      I = new FenceInst(Context, Ordering, SynchScope);
2589      InstructionList.push_back(I);
2590      break;
2591    }
2592    case bitc::FUNC_CODE_INST_CALL: {
2593      // CALL: [paramattrs, cc, fnty, fnid, arg0, arg1...]
2594      if (Record.size() < 3)
2595        return Error("Invalid CALL record");
2596
2597      AttrListPtr PAL = getAttributes(Record[0]);
2598      unsigned CCInfo = Record[1];
2599
2600      unsigned OpNum = 2;
2601      Value *Callee;
2602      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
2603        return Error("Invalid CALL record");
2604
2605      PointerType *OpTy = dyn_cast<PointerType>(Callee->getType());
2606      FunctionType *FTy = 0;
2607      if (OpTy) FTy = dyn_cast<FunctionType>(OpTy->getElementType());
2608      if (!FTy || Record.size() < FTy->getNumParams()+OpNum)
2609        return Error("Invalid CALL record");
2610
2611      SmallVector<Value*, 16> Args;
2612      // Read the fixed params.
2613      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
2614        if (FTy->getParamType(i)->isLabelTy())
2615          Args.push_back(getBasicBlock(Record[OpNum]));
2616        else
2617          Args.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
2618        if (Args.back() == 0) return Error("Invalid CALL record");
2619      }
2620
2621      // Read type/value pairs for varargs params.
2622      if (!FTy->isVarArg()) {
2623        if (OpNum != Record.size())
2624          return Error("Invalid CALL record");
2625      } else {
2626        while (OpNum != Record.size()) {
2627          Value *Op;
2628          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2629            return Error("Invalid CALL record");
2630          Args.push_back(Op);
2631        }
2632      }
2633
2634      I = CallInst::Create(Callee, Args);
2635      InstructionList.push_back(I);
2636      cast<CallInst>(I)->setCallingConv(
2637        static_cast<CallingConv::ID>(CCInfo>>1));
2638      cast<CallInst>(I)->setTailCall(CCInfo & 1);
2639      cast<CallInst>(I)->setAttributes(PAL);
2640      break;
2641    }
2642    case bitc::FUNC_CODE_INST_VAARG: { // VAARG: [valistty, valist, instty]
2643      if (Record.size() < 3)
2644        return Error("Invalid VAARG record");
2645      Type *OpTy = getTypeByID(Record[0]);
2646      Value *Op = getFnValueByID(Record[1], OpTy);
2647      Type *ResTy = getTypeByID(Record[2]);
2648      if (!OpTy || !Op || !ResTy)
2649        return Error("Invalid VAARG record");
2650      I = new VAArgInst(Op, ResTy);
2651      InstructionList.push_back(I);
2652      break;
2653    }
2654    }
2655
2656    // Add instruction to end of current BB.  If there is no current BB, reject
2657    // this file.
2658    if (CurBB == 0) {
2659      delete I;
2660      return Error("Invalid instruction with no BB");
2661    }
2662    CurBB->getInstList().push_back(I);
2663
2664    // If this was a terminator instruction, move to the next block.
2665    if (isa<TerminatorInst>(I)) {
2666      ++CurBBNo;
2667      CurBB = CurBBNo < FunctionBBs.size() ? FunctionBBs[CurBBNo] : 0;
2668    }
2669
2670    // Non-void values get registered in the value table for future use.
2671    if (I && !I->getType()->isVoidTy())
2672      ValueList.AssignValue(I, NextValueNo++);
2673  }
2674
2675  // Check the function list for unresolved values.
2676  if (Argument *A = dyn_cast<Argument>(ValueList.back())) {
2677    if (A->getParent() == 0) {
2678      // We found at least one unresolved value.  Nuke them all to avoid leaks.
2679      for (unsigned i = ModuleValueListSize, e = ValueList.size(); i != e; ++i){
2680        if ((A = dyn_cast<Argument>(ValueList[i])) && A->getParent() == 0) {
2681          A->replaceAllUsesWith(UndefValue::get(A->getType()));
2682          delete A;
2683        }
2684      }
2685      return Error("Never resolved value found in function!");
2686    }
2687  }
2688
2689  // FIXME: Check for unresolved forward-declared metadata references
2690  // and clean up leaks.
2691
2692  // See if anything took the address of blocks in this function.  If so,
2693  // resolve them now.
2694  DenseMap<Function*, std::vector<BlockAddrRefTy> >::iterator BAFRI =
2695    BlockAddrFwdRefs.find(F);
2696  if (BAFRI != BlockAddrFwdRefs.end()) {
2697    std::vector<BlockAddrRefTy> &RefList = BAFRI->second;
2698    for (unsigned i = 0, e = RefList.size(); i != e; ++i) {
2699      unsigned BlockIdx = RefList[i].first;
2700      if (BlockIdx >= FunctionBBs.size())
2701        return Error("Invalid blockaddress block #");
2702
2703      GlobalVariable *FwdRef = RefList[i].second;
2704      FwdRef->replaceAllUsesWith(BlockAddress::get(F, FunctionBBs[BlockIdx]));
2705      FwdRef->eraseFromParent();
2706    }
2707
2708    BlockAddrFwdRefs.erase(BAFRI);
2709  }
2710
2711  // Trim the value list down to the size it was before we parsed this function.
2712  ValueList.shrinkTo(ModuleValueListSize);
2713  MDValueList.shrinkTo(ModuleMDValueListSize);
2714  std::vector<BasicBlock*>().swap(FunctionBBs);
2715  return false;
2716}
2717
2718/// FindFunctionInStream - Find the function body in the bitcode stream
2719bool BitcodeReader::FindFunctionInStream(Function *F,
2720       DenseMap<Function*, uint64_t>::iterator DeferredFunctionInfoIterator) {
2721  while (DeferredFunctionInfoIterator->second == 0) {
2722    if (Stream.AtEndOfStream())
2723      return Error("Could not find Function in stream");
2724    // ParseModule will parse the next body in the stream and set its
2725    // position in the DeferredFunctionInfo map.
2726    if (ParseModule(true)) return true;
2727  }
2728  return false;
2729}
2730
2731//===----------------------------------------------------------------------===//
2732// GVMaterializer implementation
2733//===----------------------------------------------------------------------===//
2734
2735
2736bool BitcodeReader::isMaterializable(const GlobalValue *GV) const {
2737  if (const Function *F = dyn_cast<Function>(GV)) {
2738    return F->isDeclaration() &&
2739      DeferredFunctionInfo.count(const_cast<Function*>(F));
2740  }
2741  return false;
2742}
2743
2744bool BitcodeReader::Materialize(GlobalValue *GV, std::string *ErrInfo) {
2745  Function *F = dyn_cast<Function>(GV);
2746  // If it's not a function or is already material, ignore the request.
2747  if (!F || !F->isMaterializable()) return false;
2748
2749  DenseMap<Function*, uint64_t>::iterator DFII = DeferredFunctionInfo.find(F);
2750  assert(DFII != DeferredFunctionInfo.end() && "Deferred function not found!");
2751  // If its position is recorded as 0, its body is somewhere in the stream
2752  // but we haven't seen it yet.
2753  if (DFII->second == 0)
2754    if (LazyStreamer && FindFunctionInStream(F, DFII)) return true;
2755
2756  // Move the bit stream to the saved position of the deferred function body.
2757  Stream.JumpToBit(DFII->second);
2758
2759  if (ParseFunctionBody(F)) {
2760    if (ErrInfo) *ErrInfo = ErrorString;
2761    return true;
2762  }
2763
2764  // Upgrade any old intrinsic calls in the function.
2765  for (UpgradedIntrinsicMap::iterator I = UpgradedIntrinsics.begin(),
2766       E = UpgradedIntrinsics.end(); I != E; ++I) {
2767    if (I->first != I->second) {
2768      for (Value::use_iterator UI = I->first->use_begin(),
2769           UE = I->first->use_end(); UI != UE; ) {
2770        if (CallInst* CI = dyn_cast<CallInst>(*UI++))
2771          UpgradeIntrinsicCall(CI, I->second);
2772      }
2773    }
2774  }
2775
2776  return false;
2777}
2778
2779bool BitcodeReader::isDematerializable(const GlobalValue *GV) const {
2780  const Function *F = dyn_cast<Function>(GV);
2781  if (!F || F->isDeclaration())
2782    return false;
2783  return DeferredFunctionInfo.count(const_cast<Function*>(F));
2784}
2785
2786void BitcodeReader::Dematerialize(GlobalValue *GV) {
2787  Function *F = dyn_cast<Function>(GV);
2788  // If this function isn't dematerializable, this is a noop.
2789  if (!F || !isDematerializable(F))
2790    return;
2791
2792  assert(DeferredFunctionInfo.count(F) && "No info to read function later?");
2793
2794  // Just forget the function body, we can remat it later.
2795  F->deleteBody();
2796}
2797
2798
2799bool BitcodeReader::MaterializeModule(Module *M, std::string *ErrInfo) {
2800  assert(M == TheModule &&
2801         "Can only Materialize the Module this BitcodeReader is attached to.");
2802  // Iterate over the module, deserializing any functions that are still on
2803  // disk.
2804  for (Module::iterator F = TheModule->begin(), E = TheModule->end();
2805       F != E; ++F)
2806    if (F->isMaterializable() &&
2807        Materialize(F, ErrInfo))
2808      return true;
2809
2810  // At this point, if there are any function bodies, the current bit is
2811  // pointing to the END_BLOCK record after them. Now make sure the rest
2812  // of the bits in the module have been read.
2813  if (NextUnreadBit)
2814    ParseModule(true);
2815
2816  // Upgrade any intrinsic calls that slipped through (should not happen!) and
2817  // delete the old functions to clean up. We can't do this unless the entire
2818  // module is materialized because there could always be another function body
2819  // with calls to the old function.
2820  for (std::vector<std::pair<Function*, Function*> >::iterator I =
2821       UpgradedIntrinsics.begin(), E = UpgradedIntrinsics.end(); I != E; ++I) {
2822    if (I->first != I->second) {
2823      for (Value::use_iterator UI = I->first->use_begin(),
2824           UE = I->first->use_end(); UI != UE; ) {
2825        if (CallInst* CI = dyn_cast<CallInst>(*UI++))
2826          UpgradeIntrinsicCall(CI, I->second);
2827      }
2828      if (!I->first->use_empty())
2829        I->first->replaceAllUsesWith(I->second);
2830      I->first->eraseFromParent();
2831    }
2832  }
2833  std::vector<std::pair<Function*, Function*> >().swap(UpgradedIntrinsics);
2834
2835  return false;
2836}
2837
2838bool BitcodeReader::InitStream() {
2839  if (LazyStreamer) return InitLazyStream();
2840  return InitStreamFromBuffer();
2841}
2842
2843bool BitcodeReader::InitStreamFromBuffer() {
2844  const unsigned char *BufPtr = (unsigned char *)Buffer->getBufferStart();
2845  const unsigned char *BufEnd = BufPtr+Buffer->getBufferSize();
2846
2847  if (Buffer->getBufferSize() & 3) {
2848    if (!isRawBitcode(BufPtr, BufEnd) && !isBitcodeWrapper(BufPtr, BufEnd))
2849      return Error("Invalid bitcode signature");
2850    else
2851      return Error("Bitcode stream should be a multiple of 4 bytes in length");
2852  }
2853
2854  // If we have a wrapper header, parse it and ignore the non-bc file contents.
2855  // The magic number is 0x0B17C0DE stored in little endian.
2856  if (isBitcodeWrapper(BufPtr, BufEnd))
2857    if (SkipBitcodeWrapperHeader(BufPtr, BufEnd, true))
2858      return Error("Invalid bitcode wrapper header");
2859
2860  StreamFile.reset(new BitstreamReader(BufPtr, BufEnd));
2861  Stream.init(*StreamFile);
2862
2863  return false;
2864}
2865
2866bool BitcodeReader::InitLazyStream() {
2867  // Check and strip off the bitcode wrapper; BitstreamReader expects never to
2868  // see it.
2869  StreamingMemoryObject *Bytes = new StreamingMemoryObject(LazyStreamer);
2870  StreamFile.reset(new BitstreamReader(Bytes));
2871  Stream.init(*StreamFile);
2872
2873  unsigned char buf[16];
2874  if (Bytes->readBytes(0, 16, buf, NULL) == -1)
2875    return Error("Bitcode stream must be at least 16 bytes in length");
2876
2877  if (!isBitcode(buf, buf + 16))
2878    return Error("Invalid bitcode signature");
2879
2880  if (isBitcodeWrapper(buf, buf + 4)) {
2881    const unsigned char *bitcodeStart = buf;
2882    const unsigned char *bitcodeEnd = buf + 16;
2883    SkipBitcodeWrapperHeader(bitcodeStart, bitcodeEnd, false);
2884    Bytes->dropLeadingBytes(bitcodeStart - buf);
2885    Bytes->setKnownObjectSize(bitcodeEnd - bitcodeStart);
2886  }
2887  return false;
2888}
2889
2890//===----------------------------------------------------------------------===//
2891// External interface
2892//===----------------------------------------------------------------------===//
2893
2894/// getLazyBitcodeModule - lazy function-at-a-time loading from a file.
2895///
2896Module *llvm::getLazyBitcodeModule(MemoryBuffer *Buffer,
2897                                   LLVMContext& Context,
2898                                   std::string *ErrMsg) {
2899  Module *M = new Module(Buffer->getBufferIdentifier(), Context);
2900  BitcodeReader *R = new BitcodeReader(Buffer, Context);
2901  M->setMaterializer(R);
2902  if (R->ParseBitcodeInto(M)) {
2903    if (ErrMsg)
2904      *ErrMsg = R->getErrorString();
2905
2906    delete M;  // Also deletes R.
2907    return 0;
2908  }
2909  // Have the BitcodeReader dtor delete 'Buffer'.
2910  R->setBufferOwned(true);
2911
2912  R->materializeForwardReferencedFunctions();
2913
2914  return M;
2915}
2916
2917
2918Module *llvm::getStreamedBitcodeModule(const std::string &name,
2919                                       DataStreamer *streamer,
2920                                       LLVMContext &Context,
2921                                       std::string *ErrMsg) {
2922  Module *M = new Module(name, Context);
2923  BitcodeReader *R = new BitcodeReader(streamer, Context);
2924  M->setMaterializer(R);
2925  if (R->ParseBitcodeInto(M)) {
2926    if (ErrMsg)
2927      *ErrMsg = R->getErrorString();
2928    delete M;  // Also deletes R.
2929    return 0;
2930  }
2931  R->setBufferOwned(false); // no buffer to delete
2932  return M;
2933}
2934
2935/// ParseBitcodeFile - Read the specified bitcode file, returning the module.
2936/// If an error occurs, return null and fill in *ErrMsg if non-null.
2937Module *llvm::ParseBitcodeFile(MemoryBuffer *Buffer, LLVMContext& Context,
2938                               std::string *ErrMsg){
2939  Module *M = getLazyBitcodeModule(Buffer, Context, ErrMsg);
2940  if (!M) return 0;
2941
2942  // Don't let the BitcodeReader dtor delete 'Buffer', regardless of whether
2943  // there was an error.
2944  static_cast<BitcodeReader*>(M->getMaterializer())->setBufferOwned(false);
2945
2946  // Read in the entire module, and destroy the BitcodeReader.
2947  if (M->MaterializeAllPermanently(ErrMsg)) {
2948    delete M;
2949    return 0;
2950  }
2951
2952  // TODO: Restore the use-lists to the in-memory state when the bitcode was
2953  // written.  We must defer until the Module has been fully materialized.
2954
2955  return M;
2956}
2957
2958std::string llvm::getBitcodeTargetTriple(MemoryBuffer *Buffer,
2959                                         LLVMContext& Context,
2960                                         std::string *ErrMsg) {
2961  BitcodeReader *R = new BitcodeReader(Buffer, Context);
2962  // Don't let the BitcodeReader dtor delete 'Buffer'.
2963  R->setBufferOwned(false);
2964
2965  std::string Triple("");
2966  if (R->ParseTriple(Triple))
2967    if (ErrMsg)
2968      *ErrMsg = R->getErrorString();
2969
2970  delete R;
2971  return Triple;
2972}
2973