BitcodeReader.cpp revision ce16339930a2b03e53b4e6399ef59c092a7f2cfa 
1//===- BitcodeReader.cpp - Internal BitcodeReader implementation ----------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This header defines the BitcodeReader class.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/Bitcode/ReaderWriter.h"
15#include "BitcodeReader.h"
16#include "llvm/Constants.h"
17#include "llvm/DerivedTypes.h"
18#include "llvm/InlineAsm.h"
19#include "llvm/IntrinsicInst.h"
20#include "llvm/Module.h"
21#include "llvm/Operator.h"
22#include "llvm/AutoUpgrade.h"
23#include "llvm/ADT/SmallString.h"
24#include "llvm/ADT/SmallVector.h"
25#include "llvm/Support/MathExtras.h"
26#include "llvm/Support/MemoryBuffer.h"
27#include "llvm/OperandTraits.h"
28using namespace llvm;
29
30void BitcodeReader::FreeState() {
31  if (BufferOwned)
32    delete Buffer;
33  Buffer = 0;
34  std::vector<Type*>().swap(TypeList);
35  ValueList.clear();
36  MDValueList.clear();
37
38  std::vector<AttrListPtr>().swap(MAttributes);
39  std::vector<BasicBlock*>().swap(FunctionBBs);
40  std::vector<Function*>().swap(FunctionsWithBodies);
41  DeferredFunctionInfo.clear();
42  MDKindMap.clear();
43}
44
45//===----------------------------------------------------------------------===//
46//  Helper functions to implement forward reference resolution, etc.
47//===----------------------------------------------------------------------===//
48
49/// ConvertToString - Convert a string from a record into an std::string, return
50/// true on failure.
51template<typename StrTy>
52static bool ConvertToString(SmallVector<uint64_t, 64> &Record, unsigned Idx,
53                            StrTy &Result) {
54  if (Idx > Record.size())
55    return true;
56
57  for (unsigned i = Idx, e = Record.size(); i != e; ++i)
58    Result += (char)Record[i];
59  return false;
60}
61
62static GlobalValue::LinkageTypes GetDecodedLinkage(unsigned Val) {
63  switch (Val) {
64  default: // Map unknown/new linkages to external
65  case 0:  return GlobalValue::ExternalLinkage;
66  case 1:  return GlobalValue::WeakAnyLinkage;
67  case 2:  return GlobalValue::AppendingLinkage;
68  case 3:  return GlobalValue::InternalLinkage;
69  case 4:  return GlobalValue::LinkOnceAnyLinkage;
70  case 5:  return GlobalValue::DLLImportLinkage;
71  case 6:  return GlobalValue::DLLExportLinkage;
72  case 7:  return GlobalValue::ExternalWeakLinkage;
73  case 8:  return GlobalValue::CommonLinkage;
74  case 9:  return GlobalValue::PrivateLinkage;
75  case 10: return GlobalValue::WeakODRLinkage;
76  case 11: return GlobalValue::LinkOnceODRLinkage;
77  case 12: return GlobalValue::AvailableExternallyLinkage;
78  case 13: return GlobalValue::LinkerPrivateLinkage;
79  case 14: return GlobalValue::LinkerPrivateWeakLinkage;
80  case 15: return GlobalValue::LinkerPrivateWeakDefAutoLinkage;
81  }
82}
83
84static GlobalValue::VisibilityTypes GetDecodedVisibility(unsigned Val) {
85  switch (Val) {
86  default: // Map unknown visibilities to default.
87  case 0: return GlobalValue::DefaultVisibility;
88  case 1: return GlobalValue::HiddenVisibility;
89  case 2: return GlobalValue::ProtectedVisibility;
90  }
91}
92
93static int GetDecodedCastOpcode(unsigned Val) {
94  switch (Val) {
95  default: return -1;
96  case bitc::CAST_TRUNC   : return Instruction::Trunc;
97  case bitc::CAST_ZEXT    : return Instruction::ZExt;
98  case bitc::CAST_SEXT    : return Instruction::SExt;
99  case bitc::CAST_FPTOUI  : return Instruction::FPToUI;
100  case bitc::CAST_FPTOSI  : return Instruction::FPToSI;
101  case bitc::CAST_UITOFP  : return Instruction::UIToFP;
102  case bitc::CAST_SITOFP  : return Instruction::SIToFP;
103  case bitc::CAST_FPTRUNC : return Instruction::FPTrunc;
104  case bitc::CAST_FPEXT   : return Instruction::FPExt;
105  case bitc::CAST_PTRTOINT: return Instruction::PtrToInt;
106  case bitc::CAST_INTTOPTR: return Instruction::IntToPtr;
107  case bitc::CAST_BITCAST : return Instruction::BitCast;
108  }
109}
110static int GetDecodedBinaryOpcode(unsigned Val, Type *Ty) {
111  switch (Val) {
112  default: return -1;
113  case bitc::BINOP_ADD:
114    return Ty->isFPOrFPVectorTy() ? Instruction::FAdd : Instruction::Add;
115  case bitc::BINOP_SUB:
116    return Ty->isFPOrFPVectorTy() ? Instruction::FSub : Instruction::Sub;
117  case bitc::BINOP_MUL:
118    return Ty->isFPOrFPVectorTy() ? Instruction::FMul : Instruction::Mul;
119  case bitc::BINOP_UDIV: return Instruction::UDiv;
120  case bitc::BINOP_SDIV:
121    return Ty->isFPOrFPVectorTy() ? Instruction::FDiv : Instruction::SDiv;
122  case bitc::BINOP_UREM: return Instruction::URem;
123  case bitc::BINOP_SREM:
124    return Ty->isFPOrFPVectorTy() ? Instruction::FRem : Instruction::SRem;
125  case bitc::BINOP_SHL:  return Instruction::Shl;
126  case bitc::BINOP_LSHR: return Instruction::LShr;
127  case bitc::BINOP_ASHR: return Instruction::AShr;
128  case bitc::BINOP_AND:  return Instruction::And;
129  case bitc::BINOP_OR:   return Instruction::Or;
130  case bitc::BINOP_XOR:  return Instruction::Xor;
131  }
132}
133
134static AtomicRMWInst::BinOp GetDecodedRMWOperation(unsigned Val) {
135  switch (Val) {
136  default: return AtomicRMWInst::BAD_BINOP;
137  case bitc::RMW_XCHG: return AtomicRMWInst::Xchg;
138  case bitc::RMW_ADD: return AtomicRMWInst::Add;
139  case bitc::RMW_SUB: return AtomicRMWInst::Sub;
140  case bitc::RMW_AND: return AtomicRMWInst::And;
141  case bitc::RMW_NAND: return AtomicRMWInst::Nand;
142  case bitc::RMW_OR: return AtomicRMWInst::Or;
143  case bitc::RMW_XOR: return AtomicRMWInst::Xor;
144  case bitc::RMW_MAX: return AtomicRMWInst::Max;
145  case bitc::RMW_MIN: return AtomicRMWInst::Min;
146  case bitc::RMW_UMAX: return AtomicRMWInst::UMax;
147  case bitc::RMW_UMIN: return AtomicRMWInst::UMin;
148  }
149}
150
151static AtomicOrdering GetDecodedOrdering(unsigned Val) {
152  switch (Val) {
153  case bitc::ORDERING_NOTATOMIC: return NotAtomic;
154  case bitc::ORDERING_UNORDERED: return Unordered;
155  case bitc::ORDERING_MONOTONIC: return Monotonic;
156  case bitc::ORDERING_ACQUIRE: return Acquire;
157  case bitc::ORDERING_RELEASE: return Release;
158  case bitc::ORDERING_ACQREL: return AcquireRelease;
159  default: // Map unknown orderings to sequentially-consistent.
160  case bitc::ORDERING_SEQCST: return SequentiallyConsistent;
161  }
162}
163
164static SynchronizationScope GetDecodedSynchScope(unsigned Val) {
165  switch (Val) {
166  case bitc::SYNCHSCOPE_SINGLETHREAD: return SingleThread;
167  default: // Map unknown scopes to cross-thread.
168  case bitc::SYNCHSCOPE_CROSSTHREAD: return CrossThread;
169  }
170}
171
172namespace llvm {
173namespace {
174  /// @brief A class for maintaining the slot number definition
175  /// as a placeholder for the actual definition for forward constants defs.
176  class ConstantPlaceHolder : public ConstantExpr {
177    void operator=(const ConstantPlaceHolder &); // DO NOT IMPLEMENT
178  public:
179    // allocate space for exactly one operand
180    void *operator new(size_t s) {
181      return User::operator new(s, 1);
182    }
183    explicit ConstantPlaceHolder(Type *Ty, LLVMContext& Context)
184      : ConstantExpr(Ty, Instruction::UserOp1, &Op<0>(), 1) {
185      Op<0>() = UndefValue::get(Type::getInt32Ty(Context));
186    }
187
188    /// @brief Methods to support type inquiry through isa, cast, and dyn_cast.
189    //static inline bool classof(const ConstantPlaceHolder *) { return true; }
190    static bool classof(const Value *V) {
191      return isa<ConstantExpr>(V) &&
192             cast<ConstantExpr>(V)->getOpcode() == Instruction::UserOp1;
193    }
194
195
196    /// Provide fast operand accessors
197    //DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
198  };
199}
200
201// FIXME: can we inherit this from ConstantExpr?
202template <>
203struct OperandTraits<ConstantPlaceHolder> :
204  public FixedNumOperandTraits<ConstantPlaceHolder, 1> {
205};
206}
207
208
209void BitcodeReaderValueList::AssignValue(Value *V, unsigned Idx) {
210  if (Idx == size()) {
211    push_back(V);
212    return;
213  }
214
215  if (Idx >= size())
216    resize(Idx+1);
217
218  WeakVH &OldV = ValuePtrs[Idx];
219  if (OldV == 0) {
220    OldV = V;
221    return;
222  }
223
224  // Handle constants and non-constants (e.g. instrs) differently for
225  // efficiency.
226  if (Constant *PHC = dyn_cast<Constant>(&*OldV)) {
227    ResolveConstants.push_back(std::make_pair(PHC, Idx));
228    OldV = V;
229  } else {
230    // If there was a forward reference to this value, replace it.
231    Value *PrevVal = OldV;
232    OldV->replaceAllUsesWith(V);
233    delete PrevVal;
234  }
235}
236
237
238Constant *BitcodeReaderValueList::getConstantFwdRef(unsigned Idx,
239                                                    Type *Ty) {
240  if (Idx >= size())
241    resize(Idx + 1);
242
243  if (Value *V = ValuePtrs[Idx]) {
244    assert(Ty == V->getType() && "Type mismatch in constant table!");
245    return cast<Constant>(V);
246  }
247
248  // Create and return a placeholder, which will later be RAUW'd.
249  Constant *C = new ConstantPlaceHolder(Ty, Context);
250  ValuePtrs[Idx] = C;
251  return C;
252}
253
254Value *BitcodeReaderValueList::getValueFwdRef(unsigned Idx, Type *Ty) {
255  if (Idx >= size())
256    resize(Idx + 1);
257
258  if (Value *V = ValuePtrs[Idx]) {
259    assert((Ty == 0 || Ty == V->getType()) && "Type mismatch in value table!");
260    return V;
261  }
262
263  // No type specified, must be invalid reference.
264  if (Ty == 0) return 0;
265
266  // Create and return a placeholder, which will later be RAUW'd.
267  Value *V = new Argument(Ty);
268  ValuePtrs[Idx] = V;
269  return V;
270}
271
272/// ResolveConstantForwardRefs - Once all constants are read, this method bulk
273/// resolves any forward references.  The idea behind this is that we sometimes
274/// get constants (such as large arrays) which reference *many* forward ref
275/// constants.  Replacing each of these causes a lot of thrashing when
276/// building/reuniquing the constant.  Instead of doing this, we look at all the
277/// uses and rewrite all the place holders at once for any constant that uses
278/// a placeholder.
279void BitcodeReaderValueList::ResolveConstantForwardRefs() {
280  // Sort the values by-pointer so that they are efficient to look up with a
281  // binary search.
282  std::sort(ResolveConstants.begin(), ResolveConstants.end());
283
284  SmallVector<Constant*, 64> NewOps;
285
286  while (!ResolveConstants.empty()) {
287    Value *RealVal = operator[](ResolveConstants.back().second);
288    Constant *Placeholder = ResolveConstants.back().first;
289    ResolveConstants.pop_back();
290
291    // Loop over all users of the placeholder, updating them to reference the
292    // new value.  If they reference more than one placeholder, update them all
293    // at once.
294    while (!Placeholder->use_empty()) {
295      Value::use_iterator UI = Placeholder->use_begin();
296      User *U = *UI;
297
298      // If the using object isn't uniqued, just update the operands.  This
299      // handles instructions and initializers for global variables.
300      if (!isa<Constant>(U) || isa<GlobalValue>(U)) {
301        UI.getUse().set(RealVal);
302        continue;
303      }
304
305      // Otherwise, we have a constant that uses the placeholder.  Replace that
306      // constant with a new constant that has *all* placeholder uses updated.
307      Constant *UserC = cast<Constant>(U);
308      for (User::op_iterator I = UserC->op_begin(), E = UserC->op_end();
309           I != E; ++I) {
310        Value *NewOp;
311        if (!isa<ConstantPlaceHolder>(*I)) {
312          // Not a placeholder reference.
313          NewOp = *I;
314        } else if (*I == Placeholder) {
315          // Common case is that it just references this one placeholder.
316          NewOp = RealVal;
317        } else {
318          // Otherwise, look up the placeholder in ResolveConstants.
319          ResolveConstantsTy::iterator It =
320            std::lower_bound(ResolveConstants.begin(), ResolveConstants.end(),
321                             std::pair<Constant*, unsigned>(cast<Constant>(*I),
322                                                            0));
323          assert(It != ResolveConstants.end() && It->first == *I);
324          NewOp = operator[](It->second);
325        }
326
327        NewOps.push_back(cast<Constant>(NewOp));
328      }
329
330      // Make the new constant.
331      Constant *NewC;
332      if (ConstantArray *UserCA = dyn_cast<ConstantArray>(UserC)) {
333        NewC = ConstantArray::get(UserCA->getType(), NewOps);
334      } else if (ConstantStruct *UserCS = dyn_cast<ConstantStruct>(UserC)) {
335        NewC = ConstantStruct::get(UserCS->getType(), NewOps);
336      } else if (isa<ConstantVector>(UserC)) {
337        NewC = ConstantVector::get(NewOps);
338      } else {
339        assert(isa<ConstantExpr>(UserC) && "Must be a ConstantExpr.");
340        NewC = cast<ConstantExpr>(UserC)->getWithOperands(NewOps);
341      }
342
343      UserC->replaceAllUsesWith(NewC);
344      UserC->destroyConstant();
345      NewOps.clear();
346    }
347
348    // Update all ValueHandles, they should be the only users at this point.
349    Placeholder->replaceAllUsesWith(RealVal);
350    delete Placeholder;
351  }
352}
353
354void BitcodeReaderMDValueList::AssignValue(Value *V, unsigned Idx) {
355  if (Idx == size()) {
356    push_back(V);
357    return;
358  }
359
360  if (Idx >= size())
361    resize(Idx+1);
362
363  WeakVH &OldV = MDValuePtrs[Idx];
364  if (OldV == 0) {
365    OldV = V;
366    return;
367  }
368
369  // If there was a forward reference to this value, replace it.
370  MDNode *PrevVal = cast<MDNode>(OldV);
371  OldV->replaceAllUsesWith(V);
372  MDNode::deleteTemporary(PrevVal);
373  // Deleting PrevVal sets Idx value in MDValuePtrs to null. Set new
374  // value for Idx.
375  MDValuePtrs[Idx] = V;
376}
377
378Value *BitcodeReaderMDValueList::getValueFwdRef(unsigned Idx) {
379  if (Idx >= size())
380    resize(Idx + 1);
381
382  if (Value *V = MDValuePtrs[Idx]) {
383    assert(V->getType()->isMetadataTy() && "Type mismatch in value table!");
384    return V;
385  }
386
387  // Create and return a placeholder, which will later be RAUW'd.
388  Value *V = MDNode::getTemporary(Context, ArrayRef<Value*>());
389  MDValuePtrs[Idx] = V;
390  return V;
391}
392
393Type *BitcodeReader::getTypeByID(unsigned ID) {
394  // The type table size is always specified correctly.
395  if (ID >= TypeList.size())
396    return 0;
397
398  if (Type *Ty = TypeList[ID])
399    return Ty;
400
401  // If we have a forward reference, the only possible case is when it is to a
402  // named struct.  Just create a placeholder for now.
403  return TypeList[ID] = StructType::create(Context);
404}
405
406
407//===----------------------------------------------------------------------===//
408//  Functions for parsing blocks from the bitcode file
409//===----------------------------------------------------------------------===//
410
411bool BitcodeReader::ParseAttributeBlock() {
412  if (Stream.EnterSubBlock(bitc::PARAMATTR_BLOCK_ID))
413    return Error("Malformed block record");
414
415  if (!MAttributes.empty())
416    return Error("Multiple PARAMATTR blocks found!");
417
418  SmallVector<uint64_t, 64> Record;
419
420  SmallVector<AttributeWithIndex, 8> Attrs;
421
422  // Read all the records.
423  while (1) {
424    unsigned Code = Stream.ReadCode();
425    if (Code == bitc::END_BLOCK) {
426      if (Stream.ReadBlockEnd())
427        return Error("Error at end of PARAMATTR block");
428      return false;
429    }
430
431    if (Code == bitc::ENTER_SUBBLOCK) {
432      // No known subblocks, always skip them.
433      Stream.ReadSubBlockID();
434      if (Stream.SkipBlock())
435        return Error("Malformed block record");
436      continue;
437    }
438
439    if (Code == bitc::DEFINE_ABBREV) {
440      Stream.ReadAbbrevRecord();
441      continue;
442    }
443
444    // Read a record.
445    Record.clear();
446    switch (Stream.ReadRecord(Code, Record)) {
447    default:  // Default behavior: ignore.
448      break;
449    case bitc::PARAMATTR_CODE_ENTRY: { // ENTRY: [paramidx0, attr0, ...]
450      if (Record.size() & 1)
451        return Error("Invalid ENTRY record");
452
453      // FIXME : Remove this autoupgrade code in LLVM 3.0.
454      // If Function attributes are using index 0 then transfer them
455      // to index ~0. Index 0 is used for return value attributes but used to be
456      // used for function attributes.
457      Attributes RetAttribute = Attribute::None;
458      Attributes FnAttribute = Attribute::None;
459      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
460        // FIXME: remove in LLVM 3.0
461        // The alignment is stored as a 16-bit raw value from bits 31--16.
462        // We shift the bits above 31 down by 11 bits.
463
464        unsigned Alignment = (Record[i+1] & (0xffffull << 16)) >> 16;
465        if (Alignment && !isPowerOf2_32(Alignment))
466          return Error("Alignment is not a power of two.");
467
468        Attributes ReconstitutedAttr = Record[i+1] & 0xffff;
469        if (Alignment)
470          ReconstitutedAttr |= Attribute::constructAlignmentFromInt(Alignment);
471        ReconstitutedAttr |= (Record[i+1] & (0xffffull << 32)) >> 11;
472        Record[i+1] = ReconstitutedAttr;
473
474        if (Record[i] == 0)
475          RetAttribute = Record[i+1];
476        else if (Record[i] == ~0U)
477          FnAttribute = Record[i+1];
478      }
479
480      unsigned OldRetAttrs = (Attribute::NoUnwind|Attribute::NoReturn|
481                              Attribute::ReadOnly|Attribute::ReadNone);
482
483      if (FnAttribute == Attribute::None && RetAttribute != Attribute::None &&
484          (RetAttribute & OldRetAttrs) != 0) {
485        if (FnAttribute == Attribute::None) { // add a slot so they get added.
486          Record.push_back(~0U);
487          Record.push_back(0);
488        }
489
490        FnAttribute  |= RetAttribute & OldRetAttrs;
491        RetAttribute &= ~OldRetAttrs;
492      }
493
494      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
495        if (Record[i] == 0) {
496          if (RetAttribute != Attribute::None)
497            Attrs.push_back(AttributeWithIndex::get(0, RetAttribute));
498        } else if (Record[i] == ~0U) {
499          if (FnAttribute != Attribute::None)
500            Attrs.push_back(AttributeWithIndex::get(~0U, FnAttribute));
501        } else if (Record[i+1] != Attribute::None)
502          Attrs.push_back(AttributeWithIndex::get(Record[i], Record[i+1]));
503      }
504
505      MAttributes.push_back(AttrListPtr::get(Attrs.begin(), Attrs.end()));
506      Attrs.clear();
507      break;
508    }
509    }
510  }
511}
512
513bool BitcodeReader::ParseTypeTable() {
514  if (Stream.EnterSubBlock(bitc::TYPE_BLOCK_ID_NEW))
515    return Error("Malformed block record");
516
517  return ParseTypeTableBody();
518}
519
520bool BitcodeReader::ParseTypeTableBody() {
521  if (!TypeList.empty())
522    return Error("Multiple TYPE_BLOCKs found!");
523
524  SmallVector<uint64_t, 64> Record;
525  unsigned NumRecords = 0;
526
527  SmallString<64> TypeName;
528
529  // Read all the records for this type table.
530  while (1) {
531    unsigned Code = Stream.ReadCode();
532    if (Code == bitc::END_BLOCK) {
533      if (NumRecords != TypeList.size())
534        return Error("Invalid type forward reference in TYPE_BLOCK");
535      if (Stream.ReadBlockEnd())
536        return Error("Error at end of type table block");
537      return false;
538    }
539
540    if (Code == bitc::ENTER_SUBBLOCK) {
541      // No known subblocks, always skip them.
542      Stream.ReadSubBlockID();
543      if (Stream.SkipBlock())
544        return Error("Malformed block record");
545      continue;
546    }
547
548    if (Code == bitc::DEFINE_ABBREV) {
549      Stream.ReadAbbrevRecord();
550      continue;
551    }
552
553    // Read a record.
554    Record.clear();
555    Type *ResultTy = 0;
556    switch (Stream.ReadRecord(Code, Record)) {
557    default: return Error("unknown type in type table");
558    case bitc::TYPE_CODE_NUMENTRY: // TYPE_CODE_NUMENTRY: [numentries]
559      // TYPE_CODE_NUMENTRY contains a count of the number of types in the
560      // type list.  This allows us to reserve space.
561      if (Record.size() < 1)
562        return Error("Invalid TYPE_CODE_NUMENTRY record");
563      TypeList.resize(Record[0]);
564      continue;
565    case bitc::TYPE_CODE_VOID:      // VOID
566      ResultTy = Type::getVoidTy(Context);
567      break;
568    case bitc::TYPE_CODE_HALF:     // HALF
569      ResultTy = Type::getHalfTy(Context);
570      break;
571    case bitc::TYPE_CODE_FLOAT:     // FLOAT
572      ResultTy = Type::getFloatTy(Context);
573      break;
574    case bitc::TYPE_CODE_DOUBLE:    // DOUBLE
575      ResultTy = Type::getDoubleTy(Context);
576      break;
577    case bitc::TYPE_CODE_X86_FP80:  // X86_FP80
578      ResultTy = Type::getX86_FP80Ty(Context);
579      break;
580    case bitc::TYPE_CODE_FP128:     // FP128
581      ResultTy = Type::getFP128Ty(Context);
582      break;
583    case bitc::TYPE_CODE_PPC_FP128: // PPC_FP128
584      ResultTy = Type::getPPC_FP128Ty(Context);
585      break;
586    case bitc::TYPE_CODE_LABEL:     // LABEL
587      ResultTy = Type::getLabelTy(Context);
588      break;
589    case bitc::TYPE_CODE_METADATA:  // METADATA
590      ResultTy = Type::getMetadataTy(Context);
591      break;
592    case bitc::TYPE_CODE_X86_MMX:   // X86_MMX
593      ResultTy = Type::getX86_MMXTy(Context);
594      break;
595    case bitc::TYPE_CODE_INTEGER:   // INTEGER: [width]
596      if (Record.size() < 1)
597        return Error("Invalid Integer type record");
598
599      ResultTy = IntegerType::get(Context, Record[0]);
600      break;
601    case bitc::TYPE_CODE_POINTER: { // POINTER: [pointee type] or
602                                    //          [pointee type, address space]
603      if (Record.size() < 1)
604        return Error("Invalid POINTER type record");
605      unsigned AddressSpace = 0;
606      if (Record.size() == 2)
607        AddressSpace = Record[1];
608      ResultTy = getTypeByID(Record[0]);
609      if (ResultTy == 0) return Error("invalid element type in pointer type");
610      ResultTy = PointerType::get(ResultTy, AddressSpace);
611      break;
612    }
613    case bitc::TYPE_CODE_FUNCTION_OLD: {
614      // FIXME: attrid is dead, remove it in LLVM 3.0
615      // FUNCTION: [vararg, attrid, retty, paramty x N]
616      if (Record.size() < 3)
617        return Error("Invalid FUNCTION type record");
618      std::vector<Type*> ArgTys;
619      for (unsigned i = 3, e = Record.size(); i != e; ++i) {
620        if (Type *T = getTypeByID(Record[i]))
621          ArgTys.push_back(T);
622        else
623          break;
624      }
625
626      ResultTy = getTypeByID(Record[2]);
627      if (ResultTy == 0 || ArgTys.size() < Record.size()-3)
628        return Error("invalid type in function type");
629
630      ResultTy = FunctionType::get(ResultTy, ArgTys, Record[0]);
631      break;
632    }
633    case bitc::TYPE_CODE_FUNCTION: {
634      // FUNCTION: [vararg, retty, paramty x N]
635      if (Record.size() < 2)
636        return Error("Invalid FUNCTION type record");
637      std::vector<Type*> ArgTys;
638      for (unsigned i = 2, e = Record.size(); i != e; ++i) {
639        if (Type *T = getTypeByID(Record[i]))
640          ArgTys.push_back(T);
641        else
642          break;
643      }
644
645      ResultTy = getTypeByID(Record[1]);
646      if (ResultTy == 0 || ArgTys.size() < Record.size()-2)
647        return Error("invalid type in function type");
648
649      ResultTy = FunctionType::get(ResultTy, ArgTys, Record[0]);
650      break;
651    }
652    case bitc::TYPE_CODE_STRUCT_ANON: {  // STRUCT: [ispacked, eltty x N]
653      if (Record.size() < 1)
654        return Error("Invalid STRUCT type record");
655      std::vector<Type*> EltTys;
656      for (unsigned i = 1, e = Record.size(); i != e; ++i) {
657        if (Type *T = getTypeByID(Record[i]))
658          EltTys.push_back(T);
659        else
660          break;
661      }
662      if (EltTys.size() != Record.size()-1)
663        return Error("invalid type in struct type");
664      ResultTy = StructType::get(Context, EltTys, Record[0]);
665      break;
666    }
667    case bitc::TYPE_CODE_STRUCT_NAME:   // STRUCT_NAME: [strchr x N]
668      if (ConvertToString(Record, 0, TypeName))
669        return Error("Invalid STRUCT_NAME record");
670      continue;
671
672    case bitc::TYPE_CODE_STRUCT_NAMED: { // STRUCT: [ispacked, eltty x N]
673      if (Record.size() < 1)
674        return Error("Invalid STRUCT type record");
675
676      if (NumRecords >= TypeList.size())
677        return Error("invalid TYPE table");
678
679      // Check to see if this was forward referenced, if so fill in the temp.
680      StructType *Res = cast_or_null<StructType>(TypeList[NumRecords]);
681      if (Res) {
682        Res->setName(TypeName);
683        TypeList[NumRecords] = 0;
684      } else  // Otherwise, create a new struct.
685        Res = StructType::create(Context, TypeName);
686      TypeName.clear();
687
688      SmallVector<Type*, 8> EltTys;
689      for (unsigned i = 1, e = Record.size(); i != e; ++i) {
690        if (Type *T = getTypeByID(Record[i]))
691          EltTys.push_back(T);
692        else
693          break;
694      }
695      if (EltTys.size() != Record.size()-1)
696        return Error("invalid STRUCT type record");
697      Res->setBody(EltTys, Record[0]);
698      ResultTy = Res;
699      break;
700    }
701    case bitc::TYPE_CODE_OPAQUE: {       // OPAQUE: []
702      if (Record.size() != 1)
703        return Error("Invalid OPAQUE type record");
704
705      if (NumRecords >= TypeList.size())
706        return Error("invalid TYPE table");
707
708      // Check to see if this was forward referenced, if so fill in the temp.
709      StructType *Res = cast_or_null<StructType>(TypeList[NumRecords]);
710      if (Res) {
711        Res->setName(TypeName);
712        TypeList[NumRecords] = 0;
713      } else  // Otherwise, create a new struct with no body.
714        Res = StructType::create(Context, TypeName);
715      TypeName.clear();
716      ResultTy = Res;
717      break;
718    }
719    case bitc::TYPE_CODE_ARRAY:     // ARRAY: [numelts, eltty]
720      if (Record.size() < 2)
721        return Error("Invalid ARRAY type record");
722      if ((ResultTy = getTypeByID(Record[1])))
723        ResultTy = ArrayType::get(ResultTy, Record[0]);
724      else
725        return Error("Invalid ARRAY type element");
726      break;
727    case bitc::TYPE_CODE_VECTOR:    // VECTOR: [numelts, eltty]
728      if (Record.size() < 2)
729        return Error("Invalid VECTOR type record");
730      if ((ResultTy = getTypeByID(Record[1])))
731        ResultTy = VectorType::get(ResultTy, Record[0]);
732      else
733        return Error("Invalid ARRAY type element");
734      break;
735    }
736
737    if (NumRecords >= TypeList.size())
738      return Error("invalid TYPE table");
739    assert(ResultTy && "Didn't read a type?");
740    assert(TypeList[NumRecords] == 0 && "Already read type?");
741    TypeList[NumRecords++] = ResultTy;
742  }
743}
744
745bool BitcodeReader::ParseValueSymbolTable() {
746  if (Stream.EnterSubBlock(bitc::VALUE_SYMTAB_BLOCK_ID))
747    return Error("Malformed block record");
748
749  SmallVector<uint64_t, 64> Record;
750
751  // Read all the records for this value table.
752  SmallString<128> ValueName;
753  while (1) {
754    unsigned Code = Stream.ReadCode();
755    if (Code == bitc::END_BLOCK) {
756      if (Stream.ReadBlockEnd())
757        return Error("Error at end of value symbol table block");
758      return false;
759    }
760    if (Code == bitc::ENTER_SUBBLOCK) {
761      // No known subblocks, always skip them.
762      Stream.ReadSubBlockID();
763      if (Stream.SkipBlock())
764        return Error("Malformed block record");
765      continue;
766    }
767
768    if (Code == bitc::DEFINE_ABBREV) {
769      Stream.ReadAbbrevRecord();
770      continue;
771    }
772
773    // Read a record.
774    Record.clear();
775    switch (Stream.ReadRecord(Code, Record)) {
776    default:  // Default behavior: unknown type.
777      break;
778    case bitc::VST_CODE_ENTRY: {  // VST_ENTRY: [valueid, namechar x N]
779      if (ConvertToString(Record, 1, ValueName))
780        return Error("Invalid VST_ENTRY record");
781      unsigned ValueID = Record[0];
782      if (ValueID >= ValueList.size())
783        return Error("Invalid Value ID in VST_ENTRY record");
784      Value *V = ValueList[ValueID];
785
786      V->setName(StringRef(ValueName.data(), ValueName.size()));
787      ValueName.clear();
788      break;
789    }
790    case bitc::VST_CODE_BBENTRY: {
791      if (ConvertToString(Record, 1, ValueName))
792        return Error("Invalid VST_BBENTRY record");
793      BasicBlock *BB = getBasicBlock(Record[0]);
794      if (BB == 0)
795        return Error("Invalid BB ID in VST_BBENTRY record");
796
797      BB->setName(StringRef(ValueName.data(), ValueName.size()));
798      ValueName.clear();
799      break;
800    }
801    }
802  }
803}
804
805bool BitcodeReader::ParseMetadata() {
806  unsigned NextMDValueNo = MDValueList.size();
807
808  if (Stream.EnterSubBlock(bitc::METADATA_BLOCK_ID))
809    return Error("Malformed block record");
810
811  SmallVector<uint64_t, 64> Record;
812
813  // Read all the records.
814  while (1) {
815    unsigned Code = Stream.ReadCode();
816    if (Code == bitc::END_BLOCK) {
817      if (Stream.ReadBlockEnd())
818        return Error("Error at end of PARAMATTR block");
819      return false;
820    }
821
822    if (Code == bitc::ENTER_SUBBLOCK) {
823      // No known subblocks, always skip them.
824      Stream.ReadSubBlockID();
825      if (Stream.SkipBlock())
826        return Error("Malformed block record");
827      continue;
828    }
829
830    if (Code == bitc::DEFINE_ABBREV) {
831      Stream.ReadAbbrevRecord();
832      continue;
833    }
834
835    bool IsFunctionLocal = false;
836    // Read a record.
837    Record.clear();
838    Code = Stream.ReadRecord(Code, Record);
839    switch (Code) {
840    default:  // Default behavior: ignore.
841      break;
842    case bitc::METADATA_NAME: {
843      // Read named of the named metadata.
844      unsigned NameLength = Record.size();
845      SmallString<8> Name;
846      Name.resize(NameLength);
847      for (unsigned i = 0; i != NameLength; ++i)
848        Name[i] = Record[i];
849      Record.clear();
850      Code = Stream.ReadCode();
851
852      // METADATA_NAME is always followed by METADATA_NAMED_NODE.
853      unsigned NextBitCode = Stream.ReadRecord(Code, Record);
854      assert(NextBitCode == bitc::METADATA_NAMED_NODE); (void)NextBitCode;
855
856      // Read named metadata elements.
857      unsigned Size = Record.size();
858      NamedMDNode *NMD = TheModule->getOrInsertNamedMetadata(Name);
859      for (unsigned i = 0; i != Size; ++i) {
860        MDNode *MD = dyn_cast<MDNode>(MDValueList.getValueFwdRef(Record[i]));
861        if (MD == 0)
862          return Error("Malformed metadata record");
863        NMD->addOperand(MD);
864      }
865      break;
866    }
867    case bitc::METADATA_FN_NODE:
868      IsFunctionLocal = true;
869      // fall-through
870    case bitc::METADATA_NODE: {
871      if (Record.size() % 2 == 1)
872        return Error("Invalid METADATA_NODE record");
873
874      unsigned Size = Record.size();
875      SmallVector<Value*, 8> Elts;
876      for (unsigned i = 0; i != Size; i += 2) {
877        Type *Ty = getTypeByID(Record[i]);
878        if (!Ty) return Error("Invalid METADATA_NODE record");
879        if (Ty->isMetadataTy())
880          Elts.push_back(MDValueList.getValueFwdRef(Record[i+1]));
881        else if (!Ty->isVoidTy())
882          Elts.push_back(ValueList.getValueFwdRef(Record[i+1], Ty));
883        else
884          Elts.push_back(NULL);
885      }
886      Value *V = MDNode::getWhenValsUnresolved(Context, Elts, IsFunctionLocal);
887      IsFunctionLocal = false;
888      MDValueList.AssignValue(V, NextMDValueNo++);
889      break;
890    }
891    case bitc::METADATA_STRING: {
892      unsigned MDStringLength = Record.size();
893      SmallString<8> String;
894      String.resize(MDStringLength);
895      for (unsigned i = 0; i != MDStringLength; ++i)
896        String[i] = Record[i];
897      Value *V = MDString::get(Context,
898                               StringRef(String.data(), String.size()));
899      MDValueList.AssignValue(V, NextMDValueNo++);
900      break;
901    }
902    case bitc::METADATA_KIND: {
903      unsigned RecordLength = Record.size();
904      if (Record.empty() || RecordLength < 2)
905        return Error("Invalid METADATA_KIND record");
906      SmallString<8> Name;
907      Name.resize(RecordLength-1);
908      unsigned Kind = Record[0];
909      for (unsigned i = 1; i != RecordLength; ++i)
910        Name[i-1] = Record[i];
911
912      unsigned NewKind = TheModule->getMDKindID(Name.str());
913      if (!MDKindMap.insert(std::make_pair(Kind, NewKind)).second)
914        return Error("Conflicting METADATA_KIND records");
915      break;
916    }
917    }
918  }
919}
920
921/// DecodeSignRotatedValue - Decode a signed value stored with the sign bit in
922/// the LSB for dense VBR encoding.
923static uint64_t DecodeSignRotatedValue(uint64_t V) {
924  if ((V & 1) == 0)
925    return V >> 1;
926  if (V != 1)
927    return -(V >> 1);
928  // There is no such thing as -0 with integers.  "-0" really means MININT.
929  return 1ULL << 63;
930}
931
932/// ResolveGlobalAndAliasInits - Resolve all of the initializers for global
933/// values and aliases that we can.
934bool BitcodeReader::ResolveGlobalAndAliasInits() {
935  std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInitWorklist;
936  std::vector<std::pair<GlobalAlias*, unsigned> > AliasInitWorklist;
937
938  GlobalInitWorklist.swap(GlobalInits);
939  AliasInitWorklist.swap(AliasInits);
940
941  while (!GlobalInitWorklist.empty()) {
942    unsigned ValID = GlobalInitWorklist.back().second;
943    if (ValID >= ValueList.size()) {
944      // Not ready to resolve this yet, it requires something later in the file.
945      GlobalInits.push_back(GlobalInitWorklist.back());
946    } else {
947      if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
948        GlobalInitWorklist.back().first->setInitializer(C);
949      else
950        return Error("Global variable initializer is not a constant!");
951    }
952    GlobalInitWorklist.pop_back();
953  }
954
955  while (!AliasInitWorklist.empty()) {
956    unsigned ValID = AliasInitWorklist.back().second;
957    if (ValID >= ValueList.size()) {
958      AliasInits.push_back(AliasInitWorklist.back());
959    } else {
960      if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
961        AliasInitWorklist.back().first->setAliasee(C);
962      else
963        return Error("Alias initializer is not a constant!");
964    }
965    AliasInitWorklist.pop_back();
966  }
967  return false;
968}
969
970bool BitcodeReader::ParseConstants() {
971  if (Stream.EnterSubBlock(bitc::CONSTANTS_BLOCK_ID))
972    return Error("Malformed block record");
973
974  SmallVector<uint64_t, 64> Record;
975
976  // Read all the records for this value table.
977  Type *CurTy = Type::getInt32Ty(Context);
978  unsigned NextCstNo = ValueList.size();
979  while (1) {
980    unsigned Code = Stream.ReadCode();
981    if (Code == bitc::END_BLOCK)
982      break;
983
984    if (Code == bitc::ENTER_SUBBLOCK) {
985      // No known subblocks, always skip them.
986      Stream.ReadSubBlockID();
987      if (Stream.SkipBlock())
988        return Error("Malformed block record");
989      continue;
990    }
991
992    if (Code == bitc::DEFINE_ABBREV) {
993      Stream.ReadAbbrevRecord();
994      continue;
995    }
996
997    // Read a record.
998    Record.clear();
999    Value *V = 0;
1000    unsigned BitCode = Stream.ReadRecord(Code, Record);
1001    switch (BitCode) {
1002    default:  // Default behavior: unknown constant
1003    case bitc::CST_CODE_UNDEF:     // UNDEF
1004      V = UndefValue::get(CurTy);
1005      break;
1006    case bitc::CST_CODE_SETTYPE:   // SETTYPE: [typeid]
1007      if (Record.empty())
1008        return Error("Malformed CST_SETTYPE record");
1009      if (Record[0] >= TypeList.size())
1010        return Error("Invalid Type ID in CST_SETTYPE record");
1011      CurTy = TypeList[Record[0]];
1012      continue;  // Skip the ValueList manipulation.
1013    case bitc::CST_CODE_NULL:      // NULL
1014      V = Constant::getNullValue(CurTy);
1015      break;
1016    case bitc::CST_CODE_INTEGER:   // INTEGER: [intval]
1017      if (!CurTy->isIntegerTy() || Record.empty())
1018        return Error("Invalid CST_INTEGER record");
1019      V = ConstantInt::get(CurTy, DecodeSignRotatedValue(Record[0]));
1020      break;
1021    case bitc::CST_CODE_WIDE_INTEGER: {// WIDE_INTEGER: [n x intval]
1022      if (!CurTy->isIntegerTy() || Record.empty())
1023        return Error("Invalid WIDE_INTEGER record");
1024
1025      unsigned NumWords = Record.size();
1026      SmallVector<uint64_t, 8> Words;
1027      Words.resize(NumWords);
1028      for (unsigned i = 0; i != NumWords; ++i)
1029        Words[i] = DecodeSignRotatedValue(Record[i]);
1030      V = ConstantInt::get(Context,
1031                           APInt(cast<IntegerType>(CurTy)->getBitWidth(),
1032                                 Words));
1033      break;
1034    }
1035    case bitc::CST_CODE_FLOAT: {    // FLOAT: [fpval]
1036      if (Record.empty())
1037        return Error("Invalid FLOAT record");
1038      if (CurTy->isHalfTy())
1039        V = ConstantFP::get(Context, APFloat(APInt(16, (uint16_t)Record[0])));
1040      else if (CurTy->isFloatTy())
1041        V = ConstantFP::get(Context, APFloat(APInt(32, (uint32_t)Record[0])));
1042      else if (CurTy->isDoubleTy())
1043        V = ConstantFP::get(Context, APFloat(APInt(64, Record[0])));
1044      else if (CurTy->isX86_FP80Ty()) {
1045        // Bits are not stored the same way as a normal i80 APInt, compensate.
1046        uint64_t Rearrange[2];
1047        Rearrange[0] = (Record[1] & 0xffffLL) | (Record[0] << 16);
1048        Rearrange[1] = Record[0] >> 48;
1049        V = ConstantFP::get(Context, APFloat(APInt(80, Rearrange)));
1050      } else if (CurTy->isFP128Ty())
1051        V = ConstantFP::get(Context, APFloat(APInt(128, Record), true));
1052      else if (CurTy->isPPC_FP128Ty())
1053        V = ConstantFP::get(Context, APFloat(APInt(128, Record)));
1054      else
1055        V = UndefValue::get(CurTy);
1056      break;
1057    }
1058
1059    case bitc::CST_CODE_AGGREGATE: {// AGGREGATE: [n x value number]
1060      if (Record.empty())
1061        return Error("Invalid CST_AGGREGATE record");
1062
1063      unsigned Size = Record.size();
1064      std::vector<Constant*> Elts;
1065
1066      if (StructType *STy = dyn_cast<StructType>(CurTy)) {
1067        for (unsigned i = 0; i != Size; ++i)
1068          Elts.push_back(ValueList.getConstantFwdRef(Record[i],
1069                                                     STy->getElementType(i)));
1070        V = ConstantStruct::get(STy, Elts);
1071      } else if (ArrayType *ATy = dyn_cast<ArrayType>(CurTy)) {
1072        Type *EltTy = ATy->getElementType();
1073        for (unsigned i = 0; i != Size; ++i)
1074          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
1075        V = ConstantArray::get(ATy, Elts);
1076      } else if (VectorType *VTy = dyn_cast<VectorType>(CurTy)) {
1077        Type *EltTy = VTy->getElementType();
1078        for (unsigned i = 0; i != Size; ++i)
1079          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
1080        V = ConstantVector::get(Elts);
1081      } else {
1082        V = UndefValue::get(CurTy);
1083      }
1084      break;
1085    }
1086    case bitc::CST_CODE_STRING: { // STRING: [values]
1087      if (Record.empty())
1088        return Error("Invalid CST_AGGREGATE record");
1089
1090      ArrayType *ATy = cast<ArrayType>(CurTy);
1091      Type *EltTy = ATy->getElementType();
1092
1093      unsigned Size = Record.size();
1094      std::vector<Constant*> Elts;
1095      for (unsigned i = 0; i != Size; ++i)
1096        Elts.push_back(ConstantInt::get(EltTy, Record[i]));
1097      V = ConstantArray::get(ATy, Elts);
1098      break;
1099    }
1100    case bitc::CST_CODE_CSTRING: { // CSTRING: [values]
1101      if (Record.empty())
1102        return Error("Invalid CST_AGGREGATE record");
1103
1104      ArrayType *ATy = cast<ArrayType>(CurTy);
1105      Type *EltTy = ATy->getElementType();
1106
1107      unsigned Size = Record.size();
1108      std::vector<Constant*> Elts;
1109      for (unsigned i = 0; i != Size; ++i)
1110        Elts.push_back(ConstantInt::get(EltTy, Record[i]));
1111      Elts.push_back(Constant::getNullValue(EltTy));
1112      V = ConstantArray::get(ATy, Elts);
1113      break;
1114    }
1115    case bitc::CST_CODE_CE_BINOP: {  // CE_BINOP: [opcode, opval, opval]
1116      if (Record.size() < 3) return Error("Invalid CE_BINOP record");
1117      int Opc = GetDecodedBinaryOpcode(Record[0], CurTy);
1118      if (Opc < 0) {
1119        V = UndefValue::get(CurTy);  // Unknown binop.
1120      } else {
1121        Constant *LHS = ValueList.getConstantFwdRef(Record[1], CurTy);
1122        Constant *RHS = ValueList.getConstantFwdRef(Record[2], CurTy);
1123        unsigned Flags = 0;
1124        if (Record.size() >= 4) {
1125          if (Opc == Instruction::Add ||
1126              Opc == Instruction::Sub ||
1127              Opc == Instruction::Mul ||
1128              Opc == Instruction::Shl) {
1129            if (Record[3] & (1 << bitc::OBO_NO_SIGNED_WRAP))
1130              Flags |= OverflowingBinaryOperator::NoSignedWrap;
1131            if (Record[3] & (1 << bitc::OBO_NO_UNSIGNED_WRAP))
1132              Flags |= OverflowingBinaryOperator::NoUnsignedWrap;
1133          } else if (Opc == Instruction::SDiv ||
1134                     Opc == Instruction::UDiv ||
1135                     Opc == Instruction::LShr ||
1136                     Opc == Instruction::AShr) {
1137            if (Record[3] & (1 << bitc::PEO_EXACT))
1138              Flags |= SDivOperator::IsExact;
1139          }
1140        }
1141        V = ConstantExpr::get(Opc, LHS, RHS, Flags);
1142      }
1143      break;
1144    }
1145    case bitc::CST_CODE_CE_CAST: {  // CE_CAST: [opcode, opty, opval]
1146      if (Record.size() < 3) return Error("Invalid CE_CAST record");
1147      int Opc = GetDecodedCastOpcode(Record[0]);
1148      if (Opc < 0) {
1149        V = UndefValue::get(CurTy);  // Unknown cast.
1150      } else {
1151        Type *OpTy = getTypeByID(Record[1]);
1152        if (!OpTy) return Error("Invalid CE_CAST record");
1153        Constant *Op = ValueList.getConstantFwdRef(Record[2], OpTy);
1154        V = ConstantExpr::getCast(Opc, Op, CurTy);
1155      }
1156      break;
1157    }
1158    case bitc::CST_CODE_CE_INBOUNDS_GEP:
1159    case bitc::CST_CODE_CE_GEP: {  // CE_GEP:        [n x operands]
1160      if (Record.size() & 1) return Error("Invalid CE_GEP record");
1161      SmallVector<Constant*, 16> Elts;
1162      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
1163        Type *ElTy = getTypeByID(Record[i]);
1164        if (!ElTy) return Error("Invalid CE_GEP record");
1165        Elts.push_back(ValueList.getConstantFwdRef(Record[i+1], ElTy));
1166      }
1167      ArrayRef<Constant *> Indices(Elts.begin() + 1, Elts.end());
1168      V = ConstantExpr::getGetElementPtr(Elts[0], Indices,
1169                                         BitCode ==
1170                                           bitc::CST_CODE_CE_INBOUNDS_GEP);
1171      break;
1172    }
1173    case bitc::CST_CODE_CE_SELECT:  // CE_SELECT: [opval#, opval#, opval#]
1174      if (Record.size() < 3) return Error("Invalid CE_SELECT record");
1175      V = ConstantExpr::getSelect(ValueList.getConstantFwdRef(Record[0],
1176                                                              Type::getInt1Ty(Context)),
1177                                  ValueList.getConstantFwdRef(Record[1],CurTy),
1178                                  ValueList.getConstantFwdRef(Record[2],CurTy));
1179      break;
1180    case bitc::CST_CODE_CE_EXTRACTELT: { // CE_EXTRACTELT: [opty, opval, opval]
1181      if (Record.size() < 3) return Error("Invalid CE_EXTRACTELT record");
1182      VectorType *OpTy =
1183        dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
1184      if (OpTy == 0) return Error("Invalid CE_EXTRACTELT record");
1185      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1186      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], Type::getInt32Ty(Context));
1187      V = ConstantExpr::getExtractElement(Op0, Op1);
1188      break;
1189    }
1190    case bitc::CST_CODE_CE_INSERTELT: { // CE_INSERTELT: [opval, opval, opval]
1191      VectorType *OpTy = dyn_cast<VectorType>(CurTy);
1192      if (Record.size() < 3 || OpTy == 0)
1193        return Error("Invalid CE_INSERTELT record");
1194      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
1195      Constant *Op1 = ValueList.getConstantFwdRef(Record[1],
1196                                                  OpTy->getElementType());
1197      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], Type::getInt32Ty(Context));
1198      V = ConstantExpr::getInsertElement(Op0, Op1, Op2);
1199      break;
1200    }
1201    case bitc::CST_CODE_CE_SHUFFLEVEC: { // CE_SHUFFLEVEC: [opval, opval, opval]
1202      VectorType *OpTy = dyn_cast<VectorType>(CurTy);
1203      if (Record.size() < 3 || OpTy == 0)
1204        return Error("Invalid CE_SHUFFLEVEC record");
1205      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
1206      Constant *Op1 = ValueList.getConstantFwdRef(Record[1], OpTy);
1207      Type *ShufTy = VectorType::get(Type::getInt32Ty(Context),
1208                                                 OpTy->getNumElements());
1209      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], ShufTy);
1210      V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
1211      break;
1212    }
1213    case bitc::CST_CODE_CE_SHUFVEC_EX: { // [opty, opval, opval, opval]
1214      VectorType *RTy = dyn_cast<VectorType>(CurTy);
1215      VectorType *OpTy =
1216        dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
1217      if (Record.size() < 4 || RTy == 0 || OpTy == 0)
1218        return Error("Invalid CE_SHUFVEC_EX record");
1219      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1220      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
1221      Type *ShufTy = VectorType::get(Type::getInt32Ty(Context),
1222                                                 RTy->getNumElements());
1223      Constant *Op2 = ValueList.getConstantFwdRef(Record[3], ShufTy);
1224      V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
1225      break;
1226    }
1227    case bitc::CST_CODE_CE_CMP: {     // CE_CMP: [opty, opval, opval, pred]
1228      if (Record.size() < 4) return Error("Invalid CE_CMP record");
1229      Type *OpTy = getTypeByID(Record[0]);
1230      if (OpTy == 0) return Error("Invalid CE_CMP record");
1231      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1232      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
1233
1234      if (OpTy->isFPOrFPVectorTy())
1235        V = ConstantExpr::getFCmp(Record[3], Op0, Op1);
1236      else
1237        V = ConstantExpr::getICmp(Record[3], Op0, Op1);
1238      break;
1239    }
1240    case bitc::CST_CODE_INLINEASM: {
1241      if (Record.size() < 2) return Error("Invalid INLINEASM record");
1242      std::string AsmStr, ConstrStr;
1243      bool HasSideEffects = Record[0] & 1;
1244      bool IsAlignStack = Record[0] >> 1;
1245      unsigned AsmStrSize = Record[1];
1246      if (2+AsmStrSize >= Record.size())
1247        return Error("Invalid INLINEASM record");
1248      unsigned ConstStrSize = Record[2+AsmStrSize];
1249      if (3+AsmStrSize+ConstStrSize > Record.size())
1250        return Error("Invalid INLINEASM record");
1251
1252      for (unsigned i = 0; i != AsmStrSize; ++i)
1253        AsmStr += (char)Record[2+i];
1254      for (unsigned i = 0; i != ConstStrSize; ++i)
1255        ConstrStr += (char)Record[3+AsmStrSize+i];
1256      PointerType *PTy = cast<PointerType>(CurTy);
1257      V = InlineAsm::get(cast<FunctionType>(PTy->getElementType()),
1258                         AsmStr, ConstrStr, HasSideEffects, IsAlignStack);
1259      break;
1260    }
1261    case bitc::CST_CODE_BLOCKADDRESS:{
1262      if (Record.size() < 3) return Error("Invalid CE_BLOCKADDRESS record");
1263      Type *FnTy = getTypeByID(Record[0]);
1264      if (FnTy == 0) return Error("Invalid CE_BLOCKADDRESS record");
1265      Function *Fn =
1266        dyn_cast_or_null<Function>(ValueList.getConstantFwdRef(Record[1],FnTy));
1267      if (Fn == 0) return Error("Invalid CE_BLOCKADDRESS record");
1268
1269      GlobalVariable *FwdRef = new GlobalVariable(*Fn->getParent(),
1270                                                  Type::getInt8Ty(Context),
1271                                            false, GlobalValue::InternalLinkage,
1272                                                  0, "");
1273      BlockAddrFwdRefs[Fn].push_back(std::make_pair(Record[2], FwdRef));
1274      V = FwdRef;
1275      break;
1276    }
1277    }
1278
1279    ValueList.AssignValue(V, NextCstNo);
1280    ++NextCstNo;
1281  }
1282
1283  if (NextCstNo != ValueList.size())
1284    return Error("Invalid constant reference!");
1285
1286  if (Stream.ReadBlockEnd())
1287    return Error("Error at end of constants block");
1288
1289  // Once all the constants have been read, go through and resolve forward
1290  // references.
1291  ValueList.ResolveConstantForwardRefs();
1292  return false;
1293}
1294
1295bool BitcodeReader::ParseUseLists() {
1296  if (Stream.EnterSubBlock(bitc::USELIST_BLOCK_ID))
1297    return Error("Malformed block record");
1298
1299  SmallVector<uint64_t, 64> Record;
1300
1301  // Read all the records.
1302  while (1) {
1303    unsigned Code = Stream.ReadCode();
1304    if (Code == bitc::END_BLOCK) {
1305      if (Stream.ReadBlockEnd())
1306        return Error("Error at end of use-list table block");
1307      return false;
1308    }
1309
1310    if (Code == bitc::ENTER_SUBBLOCK) {
1311      // No known subblocks, always skip them.
1312      Stream.ReadSubBlockID();
1313      if (Stream.SkipBlock())
1314        return Error("Malformed block record");
1315      continue;
1316    }
1317
1318    if (Code == bitc::DEFINE_ABBREV) {
1319      Stream.ReadAbbrevRecord();
1320      continue;
1321    }
1322
1323    // Read a use list record.
1324    Record.clear();
1325    switch (Stream.ReadRecord(Code, Record)) {
1326    default:  // Default behavior: unknown type.
1327      break;
1328    case bitc::USELIST_CODE_ENTRY: { // USELIST_CODE_ENTRY: TBD.
1329      unsigned RecordLength = Record.size();
1330      if (RecordLength < 1)
1331        return Error ("Invalid UseList reader!");
1332      UseListRecords.push_back(Record);
1333      break;
1334    }
1335    }
1336  }
1337}
1338
1339/// RememberAndSkipFunctionBody - When we see the block for a function body,
1340/// remember where it is and then skip it.  This lets us lazily deserialize the
1341/// functions.
1342bool BitcodeReader::RememberAndSkipFunctionBody() {
1343  // Get the function we are talking about.
1344  if (FunctionsWithBodies.empty())
1345    return Error("Insufficient function protos");
1346
1347  Function *Fn = FunctionsWithBodies.back();
1348  FunctionsWithBodies.pop_back();
1349
1350  // Save the current stream state.
1351  uint64_t CurBit = Stream.GetCurrentBitNo();
1352  DeferredFunctionInfo[Fn] = CurBit;
1353
1354  // Skip over the function block for now.
1355  if (Stream.SkipBlock())
1356    return Error("Malformed block record");
1357  return false;
1358}
1359
1360bool BitcodeReader::ParseModule() {
1361  if (Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
1362    return Error("Malformed block record");
1363
1364  SmallVector<uint64_t, 64> Record;
1365  std::vector<std::string> SectionTable;
1366  std::vector<std::string> GCTable;
1367
1368  // Read all the records for this module.
1369  while (!Stream.AtEndOfStream()) {
1370    unsigned Code = Stream.ReadCode();
1371    if (Code == bitc::END_BLOCK) {
1372      if (Stream.ReadBlockEnd())
1373        return Error("Error at end of module block");
1374
1375      // Patch the initializers for globals and aliases up.
1376      ResolveGlobalAndAliasInits();
1377      if (!GlobalInits.empty() || !AliasInits.empty())
1378        return Error("Malformed global initializer set");
1379      if (!FunctionsWithBodies.empty())
1380        return Error("Too few function bodies found");
1381
1382      // Look for intrinsic functions which need to be upgraded at some point
1383      for (Module::iterator FI = TheModule->begin(), FE = TheModule->end();
1384           FI != FE; ++FI) {
1385        Function* NewFn;
1386        if (UpgradeIntrinsicFunction(FI, NewFn))
1387          UpgradedIntrinsics.push_back(std::make_pair(FI, NewFn));
1388      }
1389
1390      // Look for global variables which need to be renamed.
1391      for (Module::global_iterator
1392             GI = TheModule->global_begin(), GE = TheModule->global_end();
1393           GI != GE; ++GI)
1394        UpgradeGlobalVariable(GI);
1395
1396      // Force deallocation of memory for these vectors to favor the client that
1397      // want lazy deserialization.
1398      std::vector<std::pair<GlobalVariable*, unsigned> >().swap(GlobalInits);
1399      std::vector<std::pair<GlobalAlias*, unsigned> >().swap(AliasInits);
1400      std::vector<Function*>().swap(FunctionsWithBodies);
1401      return false;
1402    }
1403
1404    if (Code == bitc::ENTER_SUBBLOCK) {
1405      switch (Stream.ReadSubBlockID()) {
1406      default:  // Skip unknown content.
1407        if (Stream.SkipBlock())
1408          return Error("Malformed block record");
1409        break;
1410      case bitc::BLOCKINFO_BLOCK_ID:
1411        if (Stream.ReadBlockInfoBlock())
1412          return Error("Malformed BlockInfoBlock");
1413        break;
1414      case bitc::PARAMATTR_BLOCK_ID:
1415        if (ParseAttributeBlock())
1416          return true;
1417        break;
1418      case bitc::TYPE_BLOCK_ID_NEW:
1419        if (ParseTypeTable())
1420          return true;
1421        break;
1422      case bitc::VALUE_SYMTAB_BLOCK_ID:
1423        if (ParseValueSymbolTable())
1424          return true;
1425        break;
1426      case bitc::CONSTANTS_BLOCK_ID:
1427        if (ParseConstants() || ResolveGlobalAndAliasInits())
1428          return true;
1429        break;
1430      case bitc::METADATA_BLOCK_ID:
1431        if (ParseMetadata())
1432          return true;
1433        break;
1434      case bitc::FUNCTION_BLOCK_ID:
1435        // If this is the first function body we've seen, reverse the
1436        // FunctionsWithBodies list.
1437        if (!HasReversedFunctionsWithBodies) {
1438          std::reverse(FunctionsWithBodies.begin(), FunctionsWithBodies.end());
1439          HasReversedFunctionsWithBodies = true;
1440        }
1441
1442        if (RememberAndSkipFunctionBody())
1443          return true;
1444        break;
1445      case bitc::USELIST_BLOCK_ID:
1446        if (ParseUseLists())
1447          return true;
1448        break;
1449      }
1450      continue;
1451    }
1452
1453    if (Code == bitc::DEFINE_ABBREV) {
1454      Stream.ReadAbbrevRecord();
1455      continue;
1456    }
1457
1458    // Read a record.
1459    switch (Stream.ReadRecord(Code, Record)) {
1460    default: break;  // Default behavior, ignore unknown content.
1461    case bitc::MODULE_CODE_VERSION:  // VERSION: [version#]
1462      if (Record.size() < 1)
1463        return Error("Malformed MODULE_CODE_VERSION");
1464      // Only version #0 is supported so far.
1465      if (Record[0] != 0)
1466        return Error("Unknown bitstream version!");
1467      break;
1468    case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
1469      std::string S;
1470      if (ConvertToString(Record, 0, S))
1471        return Error("Invalid MODULE_CODE_TRIPLE record");
1472      TheModule->setTargetTriple(S);
1473      break;
1474    }
1475    case bitc::MODULE_CODE_DATALAYOUT: {  // DATALAYOUT: [strchr x N]
1476      std::string S;
1477      if (ConvertToString(Record, 0, S))
1478        return Error("Invalid MODULE_CODE_DATALAYOUT record");
1479      TheModule->setDataLayout(S);
1480      break;
1481    }
1482    case bitc::MODULE_CODE_ASM: {  // ASM: [strchr x N]
1483      std::string S;
1484      if (ConvertToString(Record, 0, S))
1485        return Error("Invalid MODULE_CODE_ASM record");
1486      TheModule->setModuleInlineAsm(S);
1487      break;
1488    }
1489    case bitc::MODULE_CODE_DEPLIB: {  // DEPLIB: [strchr x N]
1490      std::string S;
1491      if (ConvertToString(Record, 0, S))
1492        return Error("Invalid MODULE_CODE_DEPLIB record");
1493      TheModule->addLibrary(S);
1494      break;
1495    }
1496    case bitc::MODULE_CODE_SECTIONNAME: {  // SECTIONNAME: [strchr x N]
1497      std::string S;
1498      if (ConvertToString(Record, 0, S))
1499        return Error("Invalid MODULE_CODE_SECTIONNAME record");
1500      SectionTable.push_back(S);
1501      break;
1502    }
1503    case bitc::MODULE_CODE_GCNAME: {  // SECTIONNAME: [strchr x N]
1504      std::string S;
1505      if (ConvertToString(Record, 0, S))
1506        return Error("Invalid MODULE_CODE_GCNAME record");
1507      GCTable.push_back(S);
1508      break;
1509    }
1510    // GLOBALVAR: [pointer type, isconst, initid,
1511    //             linkage, alignment, section, visibility, threadlocal,
1512    //             unnamed_addr]
1513    case bitc::MODULE_CODE_GLOBALVAR: {
1514      if (Record.size() < 6)
1515        return Error("Invalid MODULE_CODE_GLOBALVAR record");
1516      Type *Ty = getTypeByID(Record[0]);
1517      if (!Ty) return Error("Invalid MODULE_CODE_GLOBALVAR record");
1518      if (!Ty->isPointerTy())
1519        return Error("Global not a pointer type!");
1520      unsigned AddressSpace = cast<PointerType>(Ty)->getAddressSpace();
1521      Ty = cast<PointerType>(Ty)->getElementType();
1522
1523      bool isConstant = Record[1];
1524      GlobalValue::LinkageTypes Linkage = GetDecodedLinkage(Record[3]);
1525      unsigned Alignment = (1 << Record[4]) >> 1;
1526      std::string Section;
1527      if (Record[5]) {
1528        if (Record[5]-1 >= SectionTable.size())
1529          return Error("Invalid section ID");
1530        Section = SectionTable[Record[5]-1];
1531      }
1532      GlobalValue::VisibilityTypes Visibility = GlobalValue::DefaultVisibility;
1533      if (Record.size() > 6)
1534        Visibility = GetDecodedVisibility(Record[6]);
1535      bool isThreadLocal = false;
1536      if (Record.size() > 7)
1537        isThreadLocal = Record[7];
1538
1539      bool UnnamedAddr = false;
1540      if (Record.size() > 8)
1541        UnnamedAddr = Record[8];
1542
1543      GlobalVariable *NewGV =
1544        new GlobalVariable(*TheModule, Ty, isConstant, Linkage, 0, "", 0,
1545                           isThreadLocal, AddressSpace);
1546      NewGV->setAlignment(Alignment);
1547      if (!Section.empty())
1548        NewGV->setSection(Section);
1549      NewGV->setVisibility(Visibility);
1550      NewGV->setThreadLocal(isThreadLocal);
1551      NewGV->setUnnamedAddr(UnnamedAddr);
1552
1553      ValueList.push_back(NewGV);
1554
1555      // Remember which value to use for the global initializer.
1556      if (unsigned InitID = Record[2])
1557        GlobalInits.push_back(std::make_pair(NewGV, InitID-1));
1558      break;
1559    }
1560    // FUNCTION:  [type, callingconv, isproto, linkage, paramattr,
1561    //             alignment, section, visibility, gc, unnamed_addr]
1562    case bitc::MODULE_CODE_FUNCTION: {
1563      if (Record.size() < 8)
1564        return Error("Invalid MODULE_CODE_FUNCTION record");
1565      Type *Ty = getTypeByID(Record[0]);
1566      if (!Ty) return Error("Invalid MODULE_CODE_FUNCTION record");
1567      if (!Ty->isPointerTy())
1568        return Error("Function not a pointer type!");
1569      FunctionType *FTy =
1570        dyn_cast<FunctionType>(cast<PointerType>(Ty)->getElementType());
1571      if (!FTy)
1572        return Error("Function not a pointer to function type!");
1573
1574      Function *Func = Function::Create(FTy, GlobalValue::ExternalLinkage,
1575                                        "", TheModule);
1576
1577      Func->setCallingConv(static_cast<CallingConv::ID>(Record[1]));
1578      bool isProto = Record[2];
1579      Func->setLinkage(GetDecodedLinkage(Record[3]));
1580      Func->setAttributes(getAttributes(Record[4]));
1581
1582      Func->setAlignment((1 << Record[5]) >> 1);
1583      if (Record[6]) {
1584        if (Record[6]-1 >= SectionTable.size())
1585          return Error("Invalid section ID");
1586        Func->setSection(SectionTable[Record[6]-1]);
1587      }
1588      Func->setVisibility(GetDecodedVisibility(Record[7]));
1589      if (Record.size() > 8 && Record[8]) {
1590        if (Record[8]-1 > GCTable.size())
1591          return Error("Invalid GC ID");
1592        Func->setGC(GCTable[Record[8]-1].c_str());
1593      }
1594      bool UnnamedAddr = false;
1595      if (Record.size() > 9)
1596        UnnamedAddr = Record[9];
1597      Func->setUnnamedAddr(UnnamedAddr);
1598      ValueList.push_back(Func);
1599
1600      // If this is a function with a body, remember the prototype we are
1601      // creating now, so that we can match up the body with them later.
1602      if (!isProto)
1603        FunctionsWithBodies.push_back(Func);
1604      break;
1605    }
1606    // ALIAS: [alias type, aliasee val#, linkage]
1607    // ALIAS: [alias type, aliasee val#, linkage, visibility]
1608    case bitc::MODULE_CODE_ALIAS: {
1609      if (Record.size() < 3)
1610        return Error("Invalid MODULE_ALIAS record");
1611      Type *Ty = getTypeByID(Record[0]);
1612      if (!Ty) return Error("Invalid MODULE_ALIAS record");
1613      if (!Ty->isPointerTy())
1614        return Error("Function not a pointer type!");
1615
1616      GlobalAlias *NewGA = new GlobalAlias(Ty, GetDecodedLinkage(Record[2]),
1617                                           "", 0, TheModule);
1618      // Old bitcode files didn't have visibility field.
1619      if (Record.size() > 3)
1620        NewGA->setVisibility(GetDecodedVisibility(Record[3]));
1621      ValueList.push_back(NewGA);
1622      AliasInits.push_back(std::make_pair(NewGA, Record[1]));
1623      break;
1624    }
1625    /// MODULE_CODE_PURGEVALS: [numvals]
1626    case bitc::MODULE_CODE_PURGEVALS:
1627      // Trim down the value list to the specified size.
1628      if (Record.size() < 1 || Record[0] > ValueList.size())
1629        return Error("Invalid MODULE_PURGEVALS record");
1630      ValueList.shrinkTo(Record[0]);
1631      break;
1632    }
1633    Record.clear();
1634  }
1635
1636  return Error("Premature end of bitstream");
1637}
1638
1639bool BitcodeReader::ParseBitcodeInto(Module *M) {
1640  TheModule = 0;
1641
1642  unsigned char *BufPtr = (unsigned char *)Buffer->getBufferStart();
1643  unsigned char *BufEnd = BufPtr+Buffer->getBufferSize();
1644
1645  if (Buffer->getBufferSize() & 3) {
1646    if (!isRawBitcode(BufPtr, BufEnd) && !isBitcodeWrapper(BufPtr, BufEnd))
1647      return Error("Invalid bitcode signature");
1648    else
1649      return Error("Bitcode stream should be a multiple of 4 bytes in length");
1650  }
1651
1652  // If we have a wrapper header, parse it and ignore the non-bc file contents.
1653  // The magic number is 0x0B17C0DE stored in little endian.
1654  if (isBitcodeWrapper(BufPtr, BufEnd))
1655    if (SkipBitcodeWrapperHeader(BufPtr, BufEnd))
1656      return Error("Invalid bitcode wrapper header");
1657
1658  StreamFile.init(BufPtr, BufEnd);
1659  Stream.init(StreamFile);
1660
1661  // Sniff for the signature.
1662  if (Stream.Read(8) != 'B' ||
1663      Stream.Read(8) != 'C' ||
1664      Stream.Read(4) != 0x0 ||
1665      Stream.Read(4) != 0xC ||
1666      Stream.Read(4) != 0xE ||
1667      Stream.Read(4) != 0xD)
1668    return Error("Invalid bitcode signature");
1669
1670  // We expect a number of well-defined blocks, though we don't necessarily
1671  // need to understand them all.
1672  while (!Stream.AtEndOfStream()) {
1673    unsigned Code = Stream.ReadCode();
1674
1675    if (Code != bitc::ENTER_SUBBLOCK) {
1676
1677      // The ranlib in xcode 4 will align archive members by appending newlines
1678      // to the end of them. If this file size is a multiple of 4 but not 8, we
1679      // have to read and ignore these final 4 bytes :-(
1680      if (Stream.GetAbbrevIDWidth() == 2 && Code == 2 &&
1681          Stream.Read(6) == 2 && Stream.Read(24) == 0xa0a0a &&
1682	  Stream.AtEndOfStream())
1683        return false;
1684
1685      return Error("Invalid record at top-level");
1686    }
1687
1688    unsigned BlockID = Stream.ReadSubBlockID();
1689
1690    // We only know the MODULE subblock ID.
1691    switch (BlockID) {
1692    case bitc::BLOCKINFO_BLOCK_ID:
1693      if (Stream.ReadBlockInfoBlock())
1694        return Error("Malformed BlockInfoBlock");
1695      break;
1696    case bitc::MODULE_BLOCK_ID:
1697      // Reject multiple MODULE_BLOCK's in a single bitstream.
1698      if (TheModule)
1699        return Error("Multiple MODULE_BLOCKs in same stream");
1700      TheModule = M;
1701      if (ParseModule())
1702        return true;
1703      break;
1704    default:
1705      if (Stream.SkipBlock())
1706        return Error("Malformed block record");
1707      break;
1708    }
1709  }
1710
1711  return false;
1712}
1713
1714bool BitcodeReader::ParseModuleTriple(std::string &Triple) {
1715  if (Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
1716    return Error("Malformed block record");
1717
1718  SmallVector<uint64_t, 64> Record;
1719
1720  // Read all the records for this module.
1721  while (!Stream.AtEndOfStream()) {
1722    unsigned Code = Stream.ReadCode();
1723    if (Code == bitc::END_BLOCK) {
1724      if (Stream.ReadBlockEnd())
1725        return Error("Error at end of module block");
1726
1727      return false;
1728    }
1729
1730    if (Code == bitc::ENTER_SUBBLOCK) {
1731      switch (Stream.ReadSubBlockID()) {
1732      default:  // Skip unknown content.
1733        if (Stream.SkipBlock())
1734          return Error("Malformed block record");
1735        break;
1736      }
1737      continue;
1738    }
1739
1740    if (Code == bitc::DEFINE_ABBREV) {
1741      Stream.ReadAbbrevRecord();
1742      continue;
1743    }
1744
1745    // Read a record.
1746    switch (Stream.ReadRecord(Code, Record)) {
1747    default: break;  // Default behavior, ignore unknown content.
1748    case bitc::MODULE_CODE_VERSION:  // VERSION: [version#]
1749      if (Record.size() < 1)
1750        return Error("Malformed MODULE_CODE_VERSION");
1751      // Only version #0 is supported so far.
1752      if (Record[0] != 0)
1753        return Error("Unknown bitstream version!");
1754      break;
1755    case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
1756      std::string S;
1757      if (ConvertToString(Record, 0, S))
1758        return Error("Invalid MODULE_CODE_TRIPLE record");
1759      Triple = S;
1760      break;
1761    }
1762    }
1763    Record.clear();
1764  }
1765
1766  return Error("Premature end of bitstream");
1767}
1768
1769bool BitcodeReader::ParseTriple(std::string &Triple) {
1770  if (Buffer->getBufferSize() & 3)
1771    return Error("Bitcode stream should be a multiple of 4 bytes in length");
1772
1773  unsigned char *BufPtr = (unsigned char *)Buffer->getBufferStart();
1774  unsigned char *BufEnd = BufPtr+Buffer->getBufferSize();
1775
1776  // If we have a wrapper header, parse it and ignore the non-bc file contents.
1777  // The magic number is 0x0B17C0DE stored in little endian.
1778  if (isBitcodeWrapper(BufPtr, BufEnd))
1779    if (SkipBitcodeWrapperHeader(BufPtr, BufEnd))
1780      return Error("Invalid bitcode wrapper header");
1781
1782  StreamFile.init(BufPtr, BufEnd);
1783  Stream.init(StreamFile);
1784
1785  // Sniff for the signature.
1786  if (Stream.Read(8) != 'B' ||
1787      Stream.Read(8) != 'C' ||
1788      Stream.Read(4) != 0x0 ||
1789      Stream.Read(4) != 0xC ||
1790      Stream.Read(4) != 0xE ||
1791      Stream.Read(4) != 0xD)
1792    return Error("Invalid bitcode signature");
1793
1794  // We expect a number of well-defined blocks, though we don't necessarily
1795  // need to understand them all.
1796  while (!Stream.AtEndOfStream()) {
1797    unsigned Code = Stream.ReadCode();
1798
1799    if (Code != bitc::ENTER_SUBBLOCK)
1800      return Error("Invalid record at top-level");
1801
1802    unsigned BlockID = Stream.ReadSubBlockID();
1803
1804    // We only know the MODULE subblock ID.
1805    switch (BlockID) {
1806    case bitc::MODULE_BLOCK_ID:
1807      if (ParseModuleTriple(Triple))
1808        return true;
1809      break;
1810    default:
1811      if (Stream.SkipBlock())
1812        return Error("Malformed block record");
1813      break;
1814    }
1815  }
1816
1817  return false;
1818}
1819
1820/// ParseMetadataAttachment - Parse metadata attachments.
1821bool BitcodeReader::ParseMetadataAttachment() {
1822  if (Stream.EnterSubBlock(bitc::METADATA_ATTACHMENT_ID))
1823    return Error("Malformed block record");
1824
1825  SmallVector<uint64_t, 64> Record;
1826  while(1) {
1827    unsigned Code = Stream.ReadCode();
1828    if (Code == bitc::END_BLOCK) {
1829      if (Stream.ReadBlockEnd())
1830        return Error("Error at end of PARAMATTR block");
1831      break;
1832    }
1833    if (Code == bitc::DEFINE_ABBREV) {
1834      Stream.ReadAbbrevRecord();
1835      continue;
1836    }
1837    // Read a metadata attachment record.
1838    Record.clear();
1839    switch (Stream.ReadRecord(Code, Record)) {
1840    default:  // Default behavior: ignore.
1841      break;
1842    case bitc::METADATA_ATTACHMENT: {
1843      unsigned RecordLength = Record.size();
1844      if (Record.empty() || (RecordLength - 1) % 2 == 1)
1845        return Error ("Invalid METADATA_ATTACHMENT reader!");
1846      Instruction *Inst = InstructionList[Record[0]];
1847      for (unsigned i = 1; i != RecordLength; i = i+2) {
1848        unsigned Kind = Record[i];
1849        DenseMap<unsigned, unsigned>::iterator I =
1850          MDKindMap.find(Kind);
1851        if (I == MDKindMap.end())
1852          return Error("Invalid metadata kind ID");
1853        Value *Node = MDValueList.getValueFwdRef(Record[i+1]);
1854        Inst->setMetadata(I->second, cast<MDNode>(Node));
1855      }
1856      break;
1857    }
1858    }
1859  }
1860  return false;
1861}
1862
1863/// ParseFunctionBody - Lazily parse the specified function body block.
1864bool BitcodeReader::ParseFunctionBody(Function *F) {
1865  if (Stream.EnterSubBlock(bitc::FUNCTION_BLOCK_ID))
1866    return Error("Malformed block record");
1867
1868  InstructionList.clear();
1869  unsigned ModuleValueListSize = ValueList.size();
1870  unsigned ModuleMDValueListSize = MDValueList.size();
1871
1872  // Add all the function arguments to the value table.
1873  for(Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
1874    ValueList.push_back(I);
1875
1876  unsigned NextValueNo = ValueList.size();
1877  BasicBlock *CurBB = 0;
1878  unsigned CurBBNo = 0;
1879
1880  DebugLoc LastLoc;
1881
1882  // Read all the records.
1883  SmallVector<uint64_t, 64> Record;
1884  while (1) {
1885    unsigned Code = Stream.ReadCode();
1886    if (Code == bitc::END_BLOCK) {
1887      if (Stream.ReadBlockEnd())
1888        return Error("Error at end of function block");
1889      break;
1890    }
1891
1892    if (Code == bitc::ENTER_SUBBLOCK) {
1893      switch (Stream.ReadSubBlockID()) {
1894      default:  // Skip unknown content.
1895        if (Stream.SkipBlock())
1896          return Error("Malformed block record");
1897        break;
1898      case bitc::CONSTANTS_BLOCK_ID:
1899        if (ParseConstants()) return true;
1900        NextValueNo = ValueList.size();
1901        break;
1902      case bitc::VALUE_SYMTAB_BLOCK_ID:
1903        if (ParseValueSymbolTable()) return true;
1904        break;
1905      case bitc::METADATA_ATTACHMENT_ID:
1906        if (ParseMetadataAttachment()) return true;
1907        break;
1908      case bitc::METADATA_BLOCK_ID:
1909        if (ParseMetadata()) return true;
1910        break;
1911      }
1912      continue;
1913    }
1914
1915    if (Code == bitc::DEFINE_ABBREV) {
1916      Stream.ReadAbbrevRecord();
1917      continue;
1918    }
1919
1920    // Read a record.
1921    Record.clear();
1922    Instruction *I = 0;
1923    unsigned BitCode = Stream.ReadRecord(Code, Record);
1924    switch (BitCode) {
1925    default: // Default behavior: reject
1926      return Error("Unknown instruction");
1927    case bitc::FUNC_CODE_DECLAREBLOCKS:     // DECLAREBLOCKS: [nblocks]
1928      if (Record.size() < 1 || Record[0] == 0)
1929        return Error("Invalid DECLAREBLOCKS record");
1930      // Create all the basic blocks for the function.
1931      FunctionBBs.resize(Record[0]);
1932      for (unsigned i = 0, e = FunctionBBs.size(); i != e; ++i)
1933        FunctionBBs[i] = BasicBlock::Create(Context, "", F);
1934      CurBB = FunctionBBs[0];
1935      continue;
1936
1937    case bitc::FUNC_CODE_DEBUG_LOC_AGAIN:  // DEBUG_LOC_AGAIN
1938      // This record indicates that the last instruction is at the same
1939      // location as the previous instruction with a location.
1940      I = 0;
1941
1942      // Get the last instruction emitted.
1943      if (CurBB && !CurBB->empty())
1944        I = &CurBB->back();
1945      else if (CurBBNo && FunctionBBs[CurBBNo-1] &&
1946               !FunctionBBs[CurBBNo-1]->empty())
1947        I = &FunctionBBs[CurBBNo-1]->back();
1948
1949      if (I == 0) return Error("Invalid DEBUG_LOC_AGAIN record");
1950      I->setDebugLoc(LastLoc);
1951      I = 0;
1952      continue;
1953
1954    case bitc::FUNC_CODE_DEBUG_LOC: {      // DEBUG_LOC: [line, col, scope, ia]
1955      I = 0;     // Get the last instruction emitted.
1956      if (CurBB && !CurBB->empty())
1957        I = &CurBB->back();
1958      else if (CurBBNo && FunctionBBs[CurBBNo-1] &&
1959               !FunctionBBs[CurBBNo-1]->empty())
1960        I = &FunctionBBs[CurBBNo-1]->back();
1961      if (I == 0 || Record.size() < 4)
1962        return Error("Invalid FUNC_CODE_DEBUG_LOC record");
1963
1964      unsigned Line = Record[0], Col = Record[1];
1965      unsigned ScopeID = Record[2], IAID = Record[3];
1966
1967      MDNode *Scope = 0, *IA = 0;
1968      if (ScopeID) Scope = cast<MDNode>(MDValueList.getValueFwdRef(ScopeID-1));
1969      if (IAID)    IA = cast<MDNode>(MDValueList.getValueFwdRef(IAID-1));
1970      LastLoc = DebugLoc::get(Line, Col, Scope, IA);
1971      I->setDebugLoc(LastLoc);
1972      I = 0;
1973      continue;
1974    }
1975
1976    case bitc::FUNC_CODE_INST_BINOP: {    // BINOP: [opval, ty, opval, opcode]
1977      unsigned OpNum = 0;
1978      Value *LHS, *RHS;
1979      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
1980          getValue(Record, OpNum, LHS->getType(), RHS) ||
1981          OpNum+1 > Record.size())
1982        return Error("Invalid BINOP record");
1983
1984      int Opc = GetDecodedBinaryOpcode(Record[OpNum++], LHS->getType());
1985      if (Opc == -1) return Error("Invalid BINOP record");
1986      I = BinaryOperator::Create((Instruction::BinaryOps)Opc, LHS, RHS);
1987      InstructionList.push_back(I);
1988      if (OpNum < Record.size()) {
1989        if (Opc == Instruction::Add ||
1990            Opc == Instruction::Sub ||
1991            Opc == Instruction::Mul ||
1992            Opc == Instruction::Shl) {
1993          if (Record[OpNum] & (1 << bitc::OBO_NO_SIGNED_WRAP))
1994            cast<BinaryOperator>(I)->setHasNoSignedWrap(true);
1995          if (Record[OpNum] & (1 << bitc::OBO_NO_UNSIGNED_WRAP))
1996            cast<BinaryOperator>(I)->setHasNoUnsignedWrap(true);
1997        } else if (Opc == Instruction::SDiv ||
1998                   Opc == Instruction::UDiv ||
1999                   Opc == Instruction::LShr ||
2000                   Opc == Instruction::AShr) {
2001          if (Record[OpNum] & (1 << bitc::PEO_EXACT))
2002            cast<BinaryOperator>(I)->setIsExact(true);
2003        }
2004      }
2005      break;
2006    }
2007    case bitc::FUNC_CODE_INST_CAST: {    // CAST: [opval, opty, destty, castopc]
2008      unsigned OpNum = 0;
2009      Value *Op;
2010      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
2011          OpNum+2 != Record.size())
2012        return Error("Invalid CAST record");
2013
2014      Type *ResTy = getTypeByID(Record[OpNum]);
2015      int Opc = GetDecodedCastOpcode(Record[OpNum+1]);
2016      if (Opc == -1 || ResTy == 0)
2017        return Error("Invalid CAST record");
2018      I = CastInst::Create((Instruction::CastOps)Opc, Op, ResTy);
2019      InstructionList.push_back(I);
2020      break;
2021    }
2022    case bitc::FUNC_CODE_INST_INBOUNDS_GEP:
2023    case bitc::FUNC_CODE_INST_GEP: { // GEP: [n x operands]
2024      unsigned OpNum = 0;
2025      Value *BasePtr;
2026      if (getValueTypePair(Record, OpNum, NextValueNo, BasePtr))
2027        return Error("Invalid GEP record");
2028
2029      SmallVector<Value*, 16> GEPIdx;
2030      while (OpNum != Record.size()) {
2031        Value *Op;
2032        if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2033          return Error("Invalid GEP record");
2034        GEPIdx.push_back(Op);
2035      }
2036
2037      I = GetElementPtrInst::Create(BasePtr, GEPIdx);
2038      InstructionList.push_back(I);
2039      if (BitCode == bitc::FUNC_CODE_INST_INBOUNDS_GEP)
2040        cast<GetElementPtrInst>(I)->setIsInBounds(true);
2041      break;
2042    }
2043
2044    case bitc::FUNC_CODE_INST_EXTRACTVAL: {
2045                                       // EXTRACTVAL: [opty, opval, n x indices]
2046      unsigned OpNum = 0;
2047      Value *Agg;
2048      if (getValueTypePair(Record, OpNum, NextValueNo, Agg))
2049        return Error("Invalid EXTRACTVAL record");
2050
2051      SmallVector<unsigned, 4> EXTRACTVALIdx;
2052      for (unsigned RecSize = Record.size();
2053           OpNum != RecSize; ++OpNum) {
2054        uint64_t Index = Record[OpNum];
2055        if ((unsigned)Index != Index)
2056          return Error("Invalid EXTRACTVAL index");
2057        EXTRACTVALIdx.push_back((unsigned)Index);
2058      }
2059
2060      I = ExtractValueInst::Create(Agg, EXTRACTVALIdx);
2061      InstructionList.push_back(I);
2062      break;
2063    }
2064
2065    case bitc::FUNC_CODE_INST_INSERTVAL: {
2066                           // INSERTVAL: [opty, opval, opty, opval, n x indices]
2067      unsigned OpNum = 0;
2068      Value *Agg;
2069      if (getValueTypePair(Record, OpNum, NextValueNo, Agg))
2070        return Error("Invalid INSERTVAL record");
2071      Value *Val;
2072      if (getValueTypePair(Record, OpNum, NextValueNo, Val))
2073        return Error("Invalid INSERTVAL record");
2074
2075      SmallVector<unsigned, 4> INSERTVALIdx;
2076      for (unsigned RecSize = Record.size();
2077           OpNum != RecSize; ++OpNum) {
2078        uint64_t Index = Record[OpNum];
2079        if ((unsigned)Index != Index)
2080          return Error("Invalid INSERTVAL index");
2081        INSERTVALIdx.push_back((unsigned)Index);
2082      }
2083
2084      I = InsertValueInst::Create(Agg, Val, INSERTVALIdx);
2085      InstructionList.push_back(I);
2086      break;
2087    }
2088
2089    case bitc::FUNC_CODE_INST_SELECT: { // SELECT: [opval, ty, opval, opval]
2090      // obsolete form of select
2091      // handles select i1 ... in old bitcode
2092      unsigned OpNum = 0;
2093      Value *TrueVal, *FalseVal, *Cond;
2094      if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
2095          getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
2096          getValue(Record, OpNum, Type::getInt1Ty(Context), Cond))
2097        return Error("Invalid SELECT record");
2098
2099      I = SelectInst::Create(Cond, TrueVal, FalseVal);
2100      InstructionList.push_back(I);
2101      break;
2102    }
2103
2104    case bitc::FUNC_CODE_INST_VSELECT: {// VSELECT: [ty,opval,opval,predty,pred]
2105      // new form of select
2106      // handles select i1 or select [N x i1]
2107      unsigned OpNum = 0;
2108      Value *TrueVal, *FalseVal, *Cond;
2109      if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
2110          getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
2111          getValueTypePair(Record, OpNum, NextValueNo, Cond))
2112        return Error("Invalid SELECT record");
2113
2114      // select condition can be either i1 or [N x i1]
2115      if (VectorType* vector_type =
2116          dyn_cast<VectorType>(Cond->getType())) {
2117        // expect <n x i1>
2118        if (vector_type->getElementType() != Type::getInt1Ty(Context))
2119          return Error("Invalid SELECT condition type");
2120      } else {
2121        // expect i1
2122        if (Cond->getType() != Type::getInt1Ty(Context))
2123          return Error("Invalid SELECT condition type");
2124      }
2125
2126      I = SelectInst::Create(Cond, TrueVal, FalseVal);
2127      InstructionList.push_back(I);
2128      break;
2129    }
2130
2131    case bitc::FUNC_CODE_INST_EXTRACTELT: { // EXTRACTELT: [opty, opval, opval]
2132      unsigned OpNum = 0;
2133      Value *Vec, *Idx;
2134      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
2135          getValue(Record, OpNum, Type::getInt32Ty(Context), Idx))
2136        return Error("Invalid EXTRACTELT record");
2137      I = ExtractElementInst::Create(Vec, Idx);
2138      InstructionList.push_back(I);
2139      break;
2140    }
2141
2142    case bitc::FUNC_CODE_INST_INSERTELT: { // INSERTELT: [ty, opval,opval,opval]
2143      unsigned OpNum = 0;
2144      Value *Vec, *Elt, *Idx;
2145      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
2146          getValue(Record, OpNum,
2147                   cast<VectorType>(Vec->getType())->getElementType(), Elt) ||
2148          getValue(Record, OpNum, Type::getInt32Ty(Context), Idx))
2149        return Error("Invalid INSERTELT record");
2150      I = InsertElementInst::Create(Vec, Elt, Idx);
2151      InstructionList.push_back(I);
2152      break;
2153    }
2154
2155    case bitc::FUNC_CODE_INST_SHUFFLEVEC: {// SHUFFLEVEC: [opval,ty,opval,opval]
2156      unsigned OpNum = 0;
2157      Value *Vec1, *Vec2, *Mask;
2158      if (getValueTypePair(Record, OpNum, NextValueNo, Vec1) ||
2159          getValue(Record, OpNum, Vec1->getType(), Vec2))
2160        return Error("Invalid SHUFFLEVEC record");
2161
2162      if (getValueTypePair(Record, OpNum, NextValueNo, Mask))
2163        return Error("Invalid SHUFFLEVEC record");
2164      I = new ShuffleVectorInst(Vec1, Vec2, Mask);
2165      InstructionList.push_back(I);
2166      break;
2167    }
2168
2169    case bitc::FUNC_CODE_INST_CMP:   // CMP: [opty, opval, opval, pred]
2170      // Old form of ICmp/FCmp returning bool
2171      // Existed to differentiate between icmp/fcmp and vicmp/vfcmp which were
2172      // both legal on vectors but had different behaviour.
2173    case bitc::FUNC_CODE_INST_CMP2: { // CMP2: [opty, opval, opval, pred]
2174      // FCmp/ICmp returning bool or vector of bool
2175
2176      unsigned OpNum = 0;
2177      Value *LHS, *RHS;
2178      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
2179          getValue(Record, OpNum, LHS->getType(), RHS) ||
2180          OpNum+1 != Record.size())
2181        return Error("Invalid CMP record");
2182
2183      if (LHS->getType()->isFPOrFPVectorTy())
2184        I = new FCmpInst((FCmpInst::Predicate)Record[OpNum], LHS, RHS);
2185      else
2186        I = new ICmpInst((ICmpInst::Predicate)Record[OpNum], LHS, RHS);
2187      InstructionList.push_back(I);
2188      break;
2189    }
2190
2191    case bitc::FUNC_CODE_INST_RET: // RET: [opty,opval<optional>]
2192      {
2193        unsigned Size = Record.size();
2194        if (Size == 0) {
2195          I = ReturnInst::Create(Context);
2196          InstructionList.push_back(I);
2197          break;
2198        }
2199
2200        unsigned OpNum = 0;
2201        Value *Op = NULL;
2202        if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2203          return Error("Invalid RET record");
2204        if (OpNum != Record.size())
2205          return Error("Invalid RET record");
2206
2207        I = ReturnInst::Create(Context, Op);
2208        InstructionList.push_back(I);
2209        break;
2210      }
2211    case bitc::FUNC_CODE_INST_BR: { // BR: [bb#, bb#, opval] or [bb#]
2212      if (Record.size() != 1 && Record.size() != 3)
2213        return Error("Invalid BR record");
2214      BasicBlock *TrueDest = getBasicBlock(Record[0]);
2215      if (TrueDest == 0)
2216        return Error("Invalid BR record");
2217
2218      if (Record.size() == 1) {
2219        I = BranchInst::Create(TrueDest);
2220        InstructionList.push_back(I);
2221      }
2222      else {
2223        BasicBlock *FalseDest = getBasicBlock(Record[1]);
2224        Value *Cond = getFnValueByID(Record[2], Type::getInt1Ty(Context));
2225        if (FalseDest == 0 || Cond == 0)
2226          return Error("Invalid BR record");
2227        I = BranchInst::Create(TrueDest, FalseDest, Cond);
2228        InstructionList.push_back(I);
2229      }
2230      break;
2231    }
2232    case bitc::FUNC_CODE_INST_SWITCH: { // SWITCH: [opty, op0, op1, ...]
2233      if (Record.size() < 3 || (Record.size() & 1) == 0)
2234        return Error("Invalid SWITCH record");
2235      Type *OpTy = getTypeByID(Record[0]);
2236      Value *Cond = getFnValueByID(Record[1], OpTy);
2237      BasicBlock *Default = getBasicBlock(Record[2]);
2238      if (OpTy == 0 || Cond == 0 || Default == 0)
2239        return Error("Invalid SWITCH record");
2240      unsigned NumCases = (Record.size()-3)/2;
2241      SwitchInst *SI = SwitchInst::Create(Cond, Default, NumCases);
2242      InstructionList.push_back(SI);
2243      for (unsigned i = 0, e = NumCases; i != e; ++i) {
2244        ConstantInt *CaseVal =
2245          dyn_cast_or_null<ConstantInt>(getFnValueByID(Record[3+i*2], OpTy));
2246        BasicBlock *DestBB = getBasicBlock(Record[1+3+i*2]);
2247        if (CaseVal == 0 || DestBB == 0) {
2248          delete SI;
2249          return Error("Invalid SWITCH record!");
2250        }
2251        SI->addCase(CaseVal, DestBB);
2252      }
2253      I = SI;
2254      break;
2255    }
2256    case bitc::FUNC_CODE_INST_INDIRECTBR: { // INDIRECTBR: [opty, op0, op1, ...]
2257      if (Record.size() < 2)
2258        return Error("Invalid INDIRECTBR record");
2259      Type *OpTy = getTypeByID(Record[0]);
2260      Value *Address = getFnValueByID(Record[1], OpTy);
2261      if (OpTy == 0 || Address == 0)
2262        return Error("Invalid INDIRECTBR record");
2263      unsigned NumDests = Record.size()-2;
2264      IndirectBrInst *IBI = IndirectBrInst::Create(Address, NumDests);
2265      InstructionList.push_back(IBI);
2266      for (unsigned i = 0, e = NumDests; i != e; ++i) {
2267        if (BasicBlock *DestBB = getBasicBlock(Record[2+i])) {
2268          IBI->addDestination(DestBB);
2269        } else {
2270          delete IBI;
2271          return Error("Invalid INDIRECTBR record!");
2272        }
2273      }
2274      I = IBI;
2275      break;
2276    }
2277
2278    case bitc::FUNC_CODE_INST_INVOKE: {
2279      // INVOKE: [attrs, cc, normBB, unwindBB, fnty, op0,op1,op2, ...]
2280      if (Record.size() < 4) return Error("Invalid INVOKE record");
2281      AttrListPtr PAL = getAttributes(Record[0]);
2282      unsigned CCInfo = Record[1];
2283      BasicBlock *NormalBB = getBasicBlock(Record[2]);
2284      BasicBlock *UnwindBB = getBasicBlock(Record[3]);
2285
2286      unsigned OpNum = 4;
2287      Value *Callee;
2288      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
2289        return Error("Invalid INVOKE record");
2290
2291      PointerType *CalleeTy = dyn_cast<PointerType>(Callee->getType());
2292      FunctionType *FTy = !CalleeTy ? 0 :
2293        dyn_cast<FunctionType>(CalleeTy->getElementType());
2294
2295      // Check that the right number of fixed parameters are here.
2296      if (FTy == 0 || NormalBB == 0 || UnwindBB == 0 ||
2297          Record.size() < OpNum+FTy->getNumParams())
2298        return Error("Invalid INVOKE record");
2299
2300      SmallVector<Value*, 16> Ops;
2301      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
2302        Ops.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
2303        if (Ops.back() == 0) return Error("Invalid INVOKE record");
2304      }
2305
2306      if (!FTy->isVarArg()) {
2307        if (Record.size() != OpNum)
2308          return Error("Invalid INVOKE record");
2309      } else {
2310        // Read type/value pairs for varargs params.
2311        while (OpNum != Record.size()) {
2312          Value *Op;
2313          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2314            return Error("Invalid INVOKE record");
2315          Ops.push_back(Op);
2316        }
2317      }
2318
2319      I = InvokeInst::Create(Callee, NormalBB, UnwindBB, Ops);
2320      InstructionList.push_back(I);
2321      cast<InvokeInst>(I)->setCallingConv(
2322        static_cast<CallingConv::ID>(CCInfo));
2323      cast<InvokeInst>(I)->setAttributes(PAL);
2324      break;
2325    }
2326    case bitc::FUNC_CODE_INST_RESUME: { // RESUME: [opval]
2327      unsigned Idx = 0;
2328      Value *Val = 0;
2329      if (getValueTypePair(Record, Idx, NextValueNo, Val))
2330        return Error("Invalid RESUME record");
2331      I = ResumeInst::Create(Val);
2332      InstructionList.push_back(I);
2333      break;
2334    }
2335    case bitc::FUNC_CODE_INST_UNWIND: // UNWIND
2336      I = new UnwindInst(Context);
2337      InstructionList.push_back(I);
2338      break;
2339    case bitc::FUNC_CODE_INST_UNREACHABLE: // UNREACHABLE
2340      I = new UnreachableInst(Context);
2341      InstructionList.push_back(I);
2342      break;
2343    case bitc::FUNC_CODE_INST_PHI: { // PHI: [ty, val0,bb0, ...]
2344      if (Record.size() < 1 || ((Record.size()-1)&1))
2345        return Error("Invalid PHI record");
2346      Type *Ty = getTypeByID(Record[0]);
2347      if (!Ty) return Error("Invalid PHI record");
2348
2349      PHINode *PN = PHINode::Create(Ty, (Record.size()-1)/2);
2350      InstructionList.push_back(PN);
2351
2352      for (unsigned i = 0, e = Record.size()-1; i != e; i += 2) {
2353        Value *V = getFnValueByID(Record[1+i], Ty);
2354        BasicBlock *BB = getBasicBlock(Record[2+i]);
2355        if (!V || !BB) return Error("Invalid PHI record");
2356        PN->addIncoming(V, BB);
2357      }
2358      I = PN;
2359      break;
2360    }
2361
2362    case bitc::FUNC_CODE_INST_LANDINGPAD: {
2363      // LANDINGPAD: [ty, val, val, num, (id0,val0 ...)?]
2364      unsigned Idx = 0;
2365      if (Record.size() < 4)
2366        return Error("Invalid LANDINGPAD record");
2367      Type *Ty = getTypeByID(Record[Idx++]);
2368      if (!Ty) return Error("Invalid LANDINGPAD record");
2369      Value *PersFn = 0;
2370      if (getValueTypePair(Record, Idx, NextValueNo, PersFn))
2371        return Error("Invalid LANDINGPAD record");
2372
2373      bool IsCleanup = !!Record[Idx++];
2374      unsigned NumClauses = Record[Idx++];
2375      LandingPadInst *LP = LandingPadInst::Create(Ty, PersFn, NumClauses);
2376      LP->setCleanup(IsCleanup);
2377      for (unsigned J = 0; J != NumClauses; ++J) {
2378        LandingPadInst::ClauseType CT =
2379          LandingPadInst::ClauseType(Record[Idx++]); (void)CT;
2380        Value *Val;
2381
2382        if (getValueTypePair(Record, Idx, NextValueNo, Val)) {
2383          delete LP;
2384          return Error("Invalid LANDINGPAD record");
2385        }
2386
2387        assert((CT != LandingPadInst::Catch ||
2388                !isa<ArrayType>(Val->getType())) &&
2389               "Catch clause has a invalid type!");
2390        assert((CT != LandingPadInst::Filter ||
2391                isa<ArrayType>(Val->getType())) &&
2392               "Filter clause has invalid type!");
2393        LP->addClause(Val);
2394      }
2395
2396      I = LP;
2397      InstructionList.push_back(I);
2398      break;
2399    }
2400
2401    case bitc::FUNC_CODE_INST_ALLOCA: { // ALLOCA: [instty, opty, op, align]
2402      if (Record.size() != 4)
2403        return Error("Invalid ALLOCA record");
2404      PointerType *Ty =
2405        dyn_cast_or_null<PointerType>(getTypeByID(Record[0]));
2406      Type *OpTy = getTypeByID(Record[1]);
2407      Value *Size = getFnValueByID(Record[2], OpTy);
2408      unsigned Align = Record[3];
2409      if (!Ty || !Size) return Error("Invalid ALLOCA record");
2410      I = new AllocaInst(Ty->getElementType(), Size, (1 << Align) >> 1);
2411      InstructionList.push_back(I);
2412      break;
2413    }
2414    case bitc::FUNC_CODE_INST_LOAD: { // LOAD: [opty, op, align, vol]
2415      unsigned OpNum = 0;
2416      Value *Op;
2417      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
2418          OpNum+2 != Record.size())
2419        return Error("Invalid LOAD record");
2420
2421      I = new LoadInst(Op, "", Record[OpNum+1], (1 << Record[OpNum]) >> 1);
2422      InstructionList.push_back(I);
2423      break;
2424    }
2425    case bitc::FUNC_CODE_INST_LOADATOMIC: {
2426       // LOADATOMIC: [opty, op, align, vol, ordering, synchscope]
2427      unsigned OpNum = 0;
2428      Value *Op;
2429      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
2430          OpNum+4 != Record.size())
2431        return Error("Invalid LOADATOMIC record");
2432
2433
2434      AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]);
2435      if (Ordering == NotAtomic || Ordering == Release ||
2436          Ordering == AcquireRelease)
2437        return Error("Invalid LOADATOMIC record");
2438      if (Ordering != NotAtomic && Record[OpNum] == 0)
2439        return Error("Invalid LOADATOMIC record");
2440      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+3]);
2441
2442      I = new LoadInst(Op, "", Record[OpNum+1], (1 << Record[OpNum]) >> 1,
2443                       Ordering, SynchScope);
2444      InstructionList.push_back(I);
2445      break;
2446    }
2447    case bitc::FUNC_CODE_INST_STORE: { // STORE2:[ptrty, ptr, val, align, vol]
2448      unsigned OpNum = 0;
2449      Value *Val, *Ptr;
2450      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
2451          getValue(Record, OpNum,
2452                    cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
2453          OpNum+2 != Record.size())
2454        return Error("Invalid STORE record");
2455
2456      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1);
2457      InstructionList.push_back(I);
2458      break;
2459    }
2460    case bitc::FUNC_CODE_INST_STOREATOMIC: {
2461      // STOREATOMIC: [ptrty, ptr, val, align, vol, ordering, synchscope]
2462      unsigned OpNum = 0;
2463      Value *Val, *Ptr;
2464      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
2465          getValue(Record, OpNum,
2466                    cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
2467          OpNum+4 != Record.size())
2468        return Error("Invalid STOREATOMIC record");
2469
2470      AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]);
2471      if (Ordering == NotAtomic || Ordering == Acquire ||
2472          Ordering == AcquireRelease)
2473        return Error("Invalid STOREATOMIC record");
2474      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+3]);
2475      if (Ordering != NotAtomic && Record[OpNum] == 0)
2476        return Error("Invalid STOREATOMIC record");
2477
2478      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1,
2479                        Ordering, SynchScope);
2480      InstructionList.push_back(I);
2481      break;
2482    }
2483    case bitc::FUNC_CODE_INST_CMPXCHG: {
2484      // CMPXCHG:[ptrty, ptr, cmp, new, vol, ordering, synchscope]
2485      unsigned OpNum = 0;
2486      Value *Ptr, *Cmp, *New;
2487      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
2488          getValue(Record, OpNum,
2489                    cast<PointerType>(Ptr->getType())->getElementType(), Cmp) ||
2490          getValue(Record, OpNum,
2491                    cast<PointerType>(Ptr->getType())->getElementType(), New) ||
2492          OpNum+3 != Record.size())
2493        return Error("Invalid CMPXCHG record");
2494      AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+1]);
2495      if (Ordering == NotAtomic || Ordering == Unordered)
2496        return Error("Invalid CMPXCHG record");
2497      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+2]);
2498      I = new AtomicCmpXchgInst(Ptr, Cmp, New, Ordering, SynchScope);
2499      cast<AtomicCmpXchgInst>(I)->setVolatile(Record[OpNum]);
2500      InstructionList.push_back(I);
2501      break;
2502    }
2503    case bitc::FUNC_CODE_INST_ATOMICRMW: {
2504      // ATOMICRMW:[ptrty, ptr, val, op, vol, ordering, synchscope]
2505      unsigned OpNum = 0;
2506      Value *Ptr, *Val;
2507      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
2508          getValue(Record, OpNum,
2509                    cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
2510          OpNum+4 != Record.size())
2511        return Error("Invalid ATOMICRMW record");
2512      AtomicRMWInst::BinOp Operation = GetDecodedRMWOperation(Record[OpNum]);
2513      if (Operation < AtomicRMWInst::FIRST_BINOP ||
2514          Operation > AtomicRMWInst::LAST_BINOP)
2515        return Error("Invalid ATOMICRMW record");
2516      AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]);
2517      if (Ordering == NotAtomic || Ordering == Unordered)
2518        return Error("Invalid ATOMICRMW record");
2519      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+3]);
2520      I = new AtomicRMWInst(Operation, Ptr, Val, Ordering, SynchScope);
2521      cast<AtomicRMWInst>(I)->setVolatile(Record[OpNum+1]);
2522      InstructionList.push_back(I);
2523      break;
2524    }
2525    case bitc::FUNC_CODE_INST_FENCE: { // FENCE:[ordering, synchscope]
2526      if (2 != Record.size())
2527        return Error("Invalid FENCE record");
2528      AtomicOrdering Ordering = GetDecodedOrdering(Record[0]);
2529      if (Ordering == NotAtomic || Ordering == Unordered ||
2530          Ordering == Monotonic)
2531        return Error("Invalid FENCE record");
2532      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[1]);
2533      I = new FenceInst(Context, Ordering, SynchScope);
2534      InstructionList.push_back(I);
2535      break;
2536    }
2537    case bitc::FUNC_CODE_INST_CALL: {
2538      // CALL: [paramattrs, cc, fnty, fnid, arg0, arg1...]
2539      if (Record.size() < 3)
2540        return Error("Invalid CALL record");
2541
2542      AttrListPtr PAL = getAttributes(Record[0]);
2543      unsigned CCInfo = Record[1];
2544
2545      unsigned OpNum = 2;
2546      Value *Callee;
2547      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
2548        return Error("Invalid CALL record");
2549
2550      PointerType *OpTy = dyn_cast<PointerType>(Callee->getType());
2551      FunctionType *FTy = 0;
2552      if (OpTy) FTy = dyn_cast<FunctionType>(OpTy->getElementType());
2553      if (!FTy || Record.size() < FTy->getNumParams()+OpNum)
2554        return Error("Invalid CALL record");
2555
2556      SmallVector<Value*, 16> Args;
2557      // Read the fixed params.
2558      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
2559        if (FTy->getParamType(i)->isLabelTy())
2560          Args.push_back(getBasicBlock(Record[OpNum]));
2561        else
2562          Args.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
2563        if (Args.back() == 0) return Error("Invalid CALL record");
2564      }
2565
2566      // Read type/value pairs for varargs params.
2567      if (!FTy->isVarArg()) {
2568        if (OpNum != Record.size())
2569          return Error("Invalid CALL record");
2570      } else {
2571        while (OpNum != Record.size()) {
2572          Value *Op;
2573          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2574            return Error("Invalid CALL record");
2575          Args.push_back(Op);
2576        }
2577      }
2578
2579      I = CallInst::Create(Callee, Args);
2580      InstructionList.push_back(I);
2581      cast<CallInst>(I)->setCallingConv(
2582        static_cast<CallingConv::ID>(CCInfo>>1));
2583      cast<CallInst>(I)->setTailCall(CCInfo & 1);
2584      cast<CallInst>(I)->setAttributes(PAL);
2585      break;
2586    }
2587    case bitc::FUNC_CODE_INST_VAARG: { // VAARG: [valistty, valist, instty]
2588      if (Record.size() < 3)
2589        return Error("Invalid VAARG record");
2590      Type *OpTy = getTypeByID(Record[0]);
2591      Value *Op = getFnValueByID(Record[1], OpTy);
2592      Type *ResTy = getTypeByID(Record[2]);
2593      if (!OpTy || !Op || !ResTy)
2594        return Error("Invalid VAARG record");
2595      I = new VAArgInst(Op, ResTy);
2596      InstructionList.push_back(I);
2597      break;
2598    }
2599    }
2600
2601    // Add instruction to end of current BB.  If there is no current BB, reject
2602    // this file.
2603    if (CurBB == 0) {
2604      delete I;
2605      return Error("Invalid instruction with no BB");
2606    }
2607    CurBB->getInstList().push_back(I);
2608
2609    // If this was a terminator instruction, move to the next block.
2610    if (isa<TerminatorInst>(I)) {
2611      ++CurBBNo;
2612      CurBB = CurBBNo < FunctionBBs.size() ? FunctionBBs[CurBBNo] : 0;
2613    }
2614
2615    // Non-void values get registered in the value table for future use.
2616    if (I && !I->getType()->isVoidTy())
2617      ValueList.AssignValue(I, NextValueNo++);
2618  }
2619
2620  // Check the function list for unresolved values.
2621  if (Argument *A = dyn_cast<Argument>(ValueList.back())) {
2622    if (A->getParent() == 0) {
2623      // We found at least one unresolved value.  Nuke them all to avoid leaks.
2624      for (unsigned i = ModuleValueListSize, e = ValueList.size(); i != e; ++i){
2625        if ((A = dyn_cast<Argument>(ValueList[i])) && A->getParent() == 0) {
2626          A->replaceAllUsesWith(UndefValue::get(A->getType()));
2627          delete A;
2628        }
2629      }
2630      return Error("Never resolved value found in function!");
2631    }
2632  }
2633
2634  // FIXME: Check for unresolved forward-declared metadata references
2635  // and clean up leaks.
2636
2637  // See if anything took the address of blocks in this function.  If so,
2638  // resolve them now.
2639  DenseMap<Function*, std::vector<BlockAddrRefTy> >::iterator BAFRI =
2640    BlockAddrFwdRefs.find(F);
2641  if (BAFRI != BlockAddrFwdRefs.end()) {
2642    std::vector<BlockAddrRefTy> &RefList = BAFRI->second;
2643    for (unsigned i = 0, e = RefList.size(); i != e; ++i) {
2644      unsigned BlockIdx = RefList[i].first;
2645      if (BlockIdx >= FunctionBBs.size())
2646        return Error("Invalid blockaddress block #");
2647
2648      GlobalVariable *FwdRef = RefList[i].second;
2649      FwdRef->replaceAllUsesWith(BlockAddress::get(F, FunctionBBs[BlockIdx]));
2650      FwdRef->eraseFromParent();
2651    }
2652
2653    BlockAddrFwdRefs.erase(BAFRI);
2654  }
2655
2656  // Trim the value list down to the size it was before we parsed this function.
2657  ValueList.shrinkTo(ModuleValueListSize);
2658  MDValueList.shrinkTo(ModuleMDValueListSize);
2659  std::vector<BasicBlock*>().swap(FunctionBBs);
2660  return false;
2661}
2662
2663//===----------------------------------------------------------------------===//
2664// GVMaterializer implementation
2665//===----------------------------------------------------------------------===//
2666
2667
2668bool BitcodeReader::isMaterializable(const GlobalValue *GV) const {
2669  if (const Function *F = dyn_cast<Function>(GV)) {
2670    return F->isDeclaration() &&
2671      DeferredFunctionInfo.count(const_cast<Function*>(F));
2672  }
2673  return false;
2674}
2675
2676bool BitcodeReader::Materialize(GlobalValue *GV, std::string *ErrInfo) {
2677  Function *F = dyn_cast<Function>(GV);
2678  // If it's not a function or is already material, ignore the request.
2679  if (!F || !F->isMaterializable()) return false;
2680
2681  DenseMap<Function*, uint64_t>::iterator DFII = DeferredFunctionInfo.find(F);
2682  assert(DFII != DeferredFunctionInfo.end() && "Deferred function not found!");
2683
2684  // Move the bit stream to the saved position of the deferred function body.
2685  Stream.JumpToBit(DFII->second);
2686
2687  if (ParseFunctionBody(F)) {
2688    if (ErrInfo) *ErrInfo = ErrorString;
2689    return true;
2690  }
2691
2692  // Upgrade any old intrinsic calls in the function.
2693  for (UpgradedIntrinsicMap::iterator I = UpgradedIntrinsics.begin(),
2694       E = UpgradedIntrinsics.end(); I != E; ++I) {
2695    if (I->first != I->second) {
2696      for (Value::use_iterator UI = I->first->use_begin(),
2697           UE = I->first->use_end(); UI != UE; ) {
2698        if (CallInst* CI = dyn_cast<CallInst>(*UI++))
2699          UpgradeIntrinsicCall(CI, I->second);
2700      }
2701    }
2702  }
2703
2704  return false;
2705}
2706
2707bool BitcodeReader::isDematerializable(const GlobalValue *GV) const {
2708  const Function *F = dyn_cast<Function>(GV);
2709  if (!F || F->isDeclaration())
2710    return false;
2711  return DeferredFunctionInfo.count(const_cast<Function*>(F));
2712}
2713
2714void BitcodeReader::Dematerialize(GlobalValue *GV) {
2715  Function *F = dyn_cast<Function>(GV);
2716  // If this function isn't dematerializable, this is a noop.
2717  if (!F || !isDematerializable(F))
2718    return;
2719
2720  assert(DeferredFunctionInfo.count(F) && "No info to read function later?");
2721
2722  // Just forget the function body, we can remat it later.
2723  F->deleteBody();
2724}
2725
2726
2727bool BitcodeReader::MaterializeModule(Module *M, std::string *ErrInfo) {
2728  assert(M == TheModule &&
2729         "Can only Materialize the Module this BitcodeReader is attached to.");
2730  // Iterate over the module, deserializing any functions that are still on
2731  // disk.
2732  for (Module::iterator F = TheModule->begin(), E = TheModule->end();
2733       F != E; ++F)
2734    if (F->isMaterializable() &&
2735        Materialize(F, ErrInfo))
2736      return true;
2737
2738  // Upgrade any intrinsic calls that slipped through (should not happen!) and
2739  // delete the old functions to clean up. We can't do this unless the entire
2740  // module is materialized because there could always be another function body
2741  // with calls to the old function.
2742  for (std::vector<std::pair<Function*, Function*> >::iterator I =
2743       UpgradedIntrinsics.begin(), E = UpgradedIntrinsics.end(); I != E; ++I) {
2744    if (I->first != I->second) {
2745      for (Value::use_iterator UI = I->first->use_begin(),
2746           UE = I->first->use_end(); UI != UE; ) {
2747        if (CallInst* CI = dyn_cast<CallInst>(*UI++))
2748          UpgradeIntrinsicCall(CI, I->second);
2749      }
2750      if (!I->first->use_empty())
2751        I->first->replaceAllUsesWith(I->second);
2752      I->first->eraseFromParent();
2753    }
2754  }
2755  std::vector<std::pair<Function*, Function*> >().swap(UpgradedIntrinsics);
2756
2757  return false;
2758}
2759
2760
2761//===----------------------------------------------------------------------===//
2762// External interface
2763//===----------------------------------------------------------------------===//
2764
2765/// getLazyBitcodeModule - lazy function-at-a-time loading from a file.
2766///
2767Module *llvm::getLazyBitcodeModule(MemoryBuffer *Buffer,
2768                                   LLVMContext& Context,
2769                                   std::string *ErrMsg) {
2770  Module *M = new Module(Buffer->getBufferIdentifier(), Context);
2771  BitcodeReader *R = new BitcodeReader(Buffer, Context);
2772  M->setMaterializer(R);
2773  if (R->ParseBitcodeInto(M)) {
2774    if (ErrMsg)
2775      *ErrMsg = R->getErrorString();
2776
2777    delete M;  // Also deletes R.
2778    return 0;
2779  }
2780  // Have the BitcodeReader dtor delete 'Buffer'.
2781  R->setBufferOwned(true);
2782  return M;
2783}
2784
2785/// ParseBitcodeFile - Read the specified bitcode file, returning the module.
2786/// If an error occurs, return null and fill in *ErrMsg if non-null.
2787Module *llvm::ParseBitcodeFile(MemoryBuffer *Buffer, LLVMContext& Context,
2788                               std::string *ErrMsg){
2789  Module *M = getLazyBitcodeModule(Buffer, Context, ErrMsg);
2790  if (!M) return 0;
2791
2792  // Don't let the BitcodeReader dtor delete 'Buffer', regardless of whether
2793  // there was an error.
2794  static_cast<BitcodeReader*>(M->getMaterializer())->setBufferOwned(false);
2795
2796  // Read in the entire module, and destroy the BitcodeReader.
2797  if (M->MaterializeAllPermanently(ErrMsg)) {
2798    delete M;
2799    return 0;
2800  }
2801
2802  // TODO: Restore the use-lists to the in-memory state when the bitcode was
2803  // written.  We must defer until the Module has been fully materialized.
2804
2805  return M;
2806}
2807
2808std::string llvm::getBitcodeTargetTriple(MemoryBuffer *Buffer,
2809                                         LLVMContext& Context,
2810                                         std::string *ErrMsg) {
2811  BitcodeReader *R = new BitcodeReader(Buffer, Context);
2812  // Don't let the BitcodeReader dtor delete 'Buffer'.
2813  R->setBufferOwned(false);
2814
2815  std::string Triple("");
2816  if (R->ParseTriple(Triple))
2817    if (ErrMsg)
2818      *ErrMsg = R->getErrorString();
2819
2820  delete R;
2821  return Triple;
2822}
2823