BitcodeReader.cpp revision 98137cca7eebca946b869b010fef2821c9bf4971 
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 "BitReader_3_0.h"
16#include "llvm/ADT/STLExtras.h"
17#include "llvm/ADT/SmallString.h"
18#include "llvm/ADT/SmallVector.h"
19#include "llvm/IR/AutoUpgrade.h"
20#include "llvm/IR/Constants.h"
21#include "llvm/IR/CFG.h"
22#include "llvm/IR/DerivedTypes.h"
23#include "llvm/IR/DiagnosticPrinter.h"
24#include "llvm/IR/GVMaterializer.h"
25#include "llvm/IR/InlineAsm.h"
26#include "llvm/IR/IntrinsicInst.h"
27#include "llvm/IR/IRBuilder.h"
28#include "llvm/IR/LLVMContext.h"
29#include "llvm/IR/Module.h"
30#include "llvm/IR/OperandTraits.h"
31#include "llvm/IR/Operator.h"
32#include "llvm/ADT/SmallPtrSet.h"
33#include "llvm/Support/ManagedStatic.h"
34#include "llvm/Support/MathExtras.h"
35#include "llvm/Support/MemoryBuffer.h"
36
37using namespace llvm;
38using namespace llvm_3_0;
39
40#define FUNC_CODE_INST_UNWIND_2_7     14
41#define eh_exception_2_7             145
42#define eh_selector_2_7              149
43
44#define TYPE_BLOCK_ID_OLD_3_0         10
45#define TYPE_SYMTAB_BLOCK_ID_OLD_3_0  13
46#define TYPE_CODE_STRUCT_OLD_3_0      10
47
48namespace {
49  void FindExnAndSelIntrinsics(BasicBlock *BB, CallInst *&Exn,
50                                      CallInst *&Sel,
51                                      SmallPtrSet<BasicBlock*, 8> &Visited) {
52    if (!Visited.insert(BB).second) return;
53
54    for (BasicBlock::iterator
55           I = BB->begin(), E = BB->end(); I != E; ++I) {
56      if (CallInst *CI = dyn_cast<CallInst>(I)) {
57        switch (CI->getCalledFunction()->getIntrinsicID()) {
58        default: break;
59        case eh_exception_2_7:
60          assert(!Exn && "Found more than one eh.exception call!");
61          Exn = CI;
62          break;
63        case eh_selector_2_7:
64          assert(!Sel && "Found more than one eh.selector call!");
65          Sel = CI;
66          break;
67        }
68
69        if (Exn && Sel) return;
70      }
71    }
72
73    if (Exn && Sel) return;
74
75    for (succ_iterator I = succ_begin(BB), E = succ_end(BB); I != E; ++I) {
76      FindExnAndSelIntrinsics(*I, Exn, Sel, Visited);
77      if (Exn && Sel) return;
78    }
79  }
80
81
82
83  /// TransferClausesToLandingPadInst - Transfer the exception handling clauses
84  /// from the eh_selector call to the new landingpad instruction.
85  void TransferClausesToLandingPadInst(LandingPadInst *LPI,
86                                              CallInst *EHSel) {
87    LLVMContext &Context = LPI->getContext();
88    unsigned N = EHSel->getNumArgOperands();
89
90    for (unsigned i = N - 1; i > 1; --i) {
91      if (const ConstantInt *CI = dyn_cast<ConstantInt>(EHSel->getArgOperand(i))){
92        unsigned FilterLength = CI->getZExtValue();
93        unsigned FirstCatch = i + FilterLength + !FilterLength;
94        assert(FirstCatch <= N && "Invalid filter length");
95
96        if (FirstCatch < N)
97          for (unsigned j = FirstCatch; j < N; ++j) {
98            Value *Val = EHSel->getArgOperand(j);
99            if (!Val->hasName() || Val->getName() != "llvm.eh.catch.all.value") {
100              LPI->addClause(cast<Constant>(EHSel->getArgOperand(j)));
101            } else {
102              GlobalVariable *GV = cast<GlobalVariable>(Val);
103              LPI->addClause(GV->getInitializer());
104            }
105          }
106
107        if (!FilterLength) {
108          // Cleanup.
109          LPI->setCleanup(true);
110        } else {
111          // Filter.
112          SmallVector<Constant *, 4> TyInfo;
113          TyInfo.reserve(FilterLength - 1);
114          for (unsigned j = i + 1; j < FirstCatch; ++j)
115            TyInfo.push_back(cast<Constant>(EHSel->getArgOperand(j)));
116          ArrayType *AType =
117            ArrayType::get(!TyInfo.empty() ? TyInfo[0]->getType() :
118                           PointerType::getUnqual(Type::getInt8Ty(Context)),
119                           TyInfo.size());
120          LPI->addClause(ConstantArray::get(AType, TyInfo));
121        }
122
123        N = i;
124      }
125    }
126
127    if (N > 2)
128      for (unsigned j = 2; j < N; ++j) {
129        Value *Val = EHSel->getArgOperand(j);
130        if (!Val->hasName() || Val->getName() != "llvm.eh.catch.all.value") {
131          LPI->addClause(cast<Constant>(EHSel->getArgOperand(j)));
132        } else {
133          GlobalVariable *GV = cast<GlobalVariable>(Val);
134          LPI->addClause(GV->getInitializer());
135        }
136      }
137  }
138
139
140  /// This function upgrades the old pre-3.0 exception handling system to the new
141  /// one. N.B. This will be removed in 3.1.
142  void UpgradeExceptionHandling(Module *M) {
143    Function *EHException = M->getFunction("llvm.eh.exception");
144    Function *EHSelector = M->getFunction("llvm.eh.selector");
145    if (!EHException || !EHSelector)
146      return;
147
148    LLVMContext &Context = M->getContext();
149    Type *ExnTy = PointerType::getUnqual(Type::getInt8Ty(Context));
150    Type *SelTy = Type::getInt32Ty(Context);
151    Type *LPadSlotTy = StructType::get(ExnTy, SelTy, nullptr);
152
153    // This map links the invoke instruction with the eh.exception and eh.selector
154    // calls associated with it.
155    DenseMap<InvokeInst*, std::pair<Value*, Value*> > InvokeToIntrinsicsMap;
156    for (Module::iterator
157           I = M->begin(), E = M->end(); I != E; ++I) {
158      Function &F = *I;
159
160      for (Function::iterator
161             II = F.begin(), IE = F.end(); II != IE; ++II) {
162        BasicBlock *BB = &*II;
163        InvokeInst *Inst = dyn_cast<InvokeInst>(BB->getTerminator());
164        if (!Inst) continue;
165        BasicBlock *UnwindDest = Inst->getUnwindDest();
166        if (UnwindDest->isLandingPad()) continue; // Already converted.
167
168        SmallPtrSet<BasicBlock*, 8> Visited;
169        CallInst *Exn = 0;
170        CallInst *Sel = 0;
171        FindExnAndSelIntrinsics(UnwindDest, Exn, Sel, Visited);
172        assert(Exn && Sel && "Cannot find eh.exception and eh.selector calls!");
173        InvokeToIntrinsicsMap[Inst] = std::make_pair(Exn, Sel);
174      }
175    }
176
177    // This map stores the slots where the exception object and selector value are
178    // stored within a function.
179    DenseMap<Function*, std::pair<Value*, Value*> > FnToLPadSlotMap;
180    SmallPtrSet<Instruction*, 32> DeadInsts;
181    for (DenseMap<InvokeInst*, std::pair<Value*, Value*> >::iterator
182           I = InvokeToIntrinsicsMap.begin(), E = InvokeToIntrinsicsMap.end();
183         I != E; ++I) {
184      InvokeInst *Invoke = I->first;
185      BasicBlock *UnwindDest = Invoke->getUnwindDest();
186      Function *F = UnwindDest->getParent();
187      std::pair<Value*, Value*> EHIntrinsics = I->second;
188      CallInst *Exn = cast<CallInst>(EHIntrinsics.first);
189      CallInst *Sel = cast<CallInst>(EHIntrinsics.second);
190
191      // Store the exception object and selector value in the entry block.
192      Value *ExnSlot = 0;
193      Value *SelSlot = 0;
194      if (!FnToLPadSlotMap[F].first) {
195        BasicBlock *Entry = &F->front();
196        ExnSlot = new AllocaInst(ExnTy, "exn", Entry->getTerminator());
197        SelSlot = new AllocaInst(SelTy, "sel", Entry->getTerminator());
198        FnToLPadSlotMap[F] = std::make_pair(ExnSlot, SelSlot);
199      } else {
200        ExnSlot = FnToLPadSlotMap[F].first;
201        SelSlot = FnToLPadSlotMap[F].second;
202      }
203
204      if (!UnwindDest->getSinglePredecessor()) {
205        // The unwind destination doesn't have a single predecessor. Create an
206        // unwind destination which has only one predecessor.
207        BasicBlock *NewBB = BasicBlock::Create(Context, "new.lpad",
208                                               UnwindDest->getParent());
209        BranchInst::Create(UnwindDest, NewBB);
210        Invoke->setUnwindDest(NewBB);
211
212        // Fix up any PHIs in the original unwind destination block.
213        for (BasicBlock::iterator
214               II = UnwindDest->begin(); isa<PHINode>(II); ++II) {
215          PHINode *PN = cast<PHINode>(II);
216          int Idx = PN->getBasicBlockIndex(Invoke->getParent());
217          if (Idx == -1) continue;
218          PN->setIncomingBlock(Idx, NewBB);
219        }
220
221        UnwindDest = NewBB;
222      }
223
224      IRBuilder<> Builder(Context);
225      Builder.SetInsertPoint(UnwindDest, UnwindDest->getFirstInsertionPt());
226
227      Value *PersFn = Sel->getArgOperand(1);
228      LandingPadInst *LPI = Builder.CreateLandingPad(LPadSlotTy, PersFn, 0);
229      Value *LPExn = Builder.CreateExtractValue(LPI, 0);
230      Value *LPSel = Builder.CreateExtractValue(LPI, 1);
231      Builder.CreateStore(LPExn, ExnSlot);
232      Builder.CreateStore(LPSel, SelSlot);
233
234      TransferClausesToLandingPadInst(LPI, Sel);
235
236      DeadInsts.insert(Exn);
237      DeadInsts.insert(Sel);
238    }
239
240    // Replace the old intrinsic calls with the values from the landingpad
241    // instruction(s). These values were stored in allocas for us to use here.
242    for (DenseMap<InvokeInst*, std::pair<Value*, Value*> >::iterator
243           I = InvokeToIntrinsicsMap.begin(), E = InvokeToIntrinsicsMap.end();
244         I != E; ++I) {
245      std::pair<Value*, Value*> EHIntrinsics = I->second;
246      CallInst *Exn = cast<CallInst>(EHIntrinsics.first);
247      CallInst *Sel = cast<CallInst>(EHIntrinsics.second);
248      BasicBlock *Parent = Exn->getParent();
249
250      std::pair<Value*,Value*> ExnSelSlots = FnToLPadSlotMap[Parent->getParent()];
251
252      IRBuilder<> Builder(Context);
253      Builder.SetInsertPoint(Parent, Exn);
254      LoadInst *LPExn = Builder.CreateLoad(ExnSelSlots.first, "exn.load");
255      LoadInst *LPSel = Builder.CreateLoad(ExnSelSlots.second, "sel.load");
256
257      Exn->replaceAllUsesWith(LPExn);
258      Sel->replaceAllUsesWith(LPSel);
259    }
260
261    // Remove the dead instructions.
262    for (SmallPtrSet<Instruction*, 32>::iterator
263           I = DeadInsts.begin(), E = DeadInsts.end(); I != E; ++I) {
264      Instruction *Inst = *I;
265      Inst->eraseFromParent();
266    }
267
268    // Replace calls to "llvm.eh.resume" with the 'resume' instruction. Load the
269    // exception and selector values from the stored place.
270    Function *EHResume = M->getFunction("llvm.eh.resume");
271    if (!EHResume) return;
272
273    while (!EHResume->use_empty()) {
274      CallInst *Resume = cast<CallInst>(*EHResume->use_begin());
275      BasicBlock *BB = Resume->getParent();
276
277      IRBuilder<> Builder(Context);
278      Builder.SetInsertPoint(BB, Resume);
279
280      Value *LPadVal =
281        Builder.CreateInsertValue(UndefValue::get(LPadSlotTy),
282                                  Resume->getArgOperand(0), 0, "lpad.val");
283      LPadVal = Builder.CreateInsertValue(LPadVal, Resume->getArgOperand(1),
284                                          1, "lpad.val");
285      Builder.CreateResume(LPadVal);
286
287      // Remove all instructions after the 'resume.'
288      BasicBlock::iterator I = Resume;
289      while (I != BB->end()) {
290        Instruction *Inst = &*I++;
291        Inst->eraseFromParent();
292      }
293    }
294  }
295
296
297  void StripDebugInfoOfFunction(Module* M, const char* name) {
298    if (Function* FuncStart = M->getFunction(name)) {
299      while (!FuncStart->use_empty()) {
300        cast<CallInst>(*FuncStart->use_begin())->eraseFromParent();
301      }
302      FuncStart->eraseFromParent();
303    }
304  }
305
306  /// This function strips all debug info intrinsics, except for llvm.dbg.declare.
307  /// If an llvm.dbg.declare intrinsic is invalid, then this function simply
308  /// strips that use.
309  void CheckDebugInfoIntrinsics(Module *M) {
310    StripDebugInfoOfFunction(M, "llvm.dbg.func.start");
311    StripDebugInfoOfFunction(M, "llvm.dbg.stoppoint");
312    StripDebugInfoOfFunction(M, "llvm.dbg.region.start");
313    StripDebugInfoOfFunction(M, "llvm.dbg.region.end");
314
315    if (Function *Declare = M->getFunction("llvm.dbg.declare")) {
316      if (!Declare->use_empty()) {
317        DbgDeclareInst *DDI = cast<DbgDeclareInst>(*Declare->use_begin());
318        if (!isa<MDNode>(ValueAsMetadata::get(DDI->getArgOperand(0))) ||
319            !isa<MDNode>(ValueAsMetadata::get(DDI->getArgOperand(1)))) {
320          while (!Declare->use_empty()) {
321            CallInst *CI = cast<CallInst>(*Declare->use_begin());
322            CI->eraseFromParent();
323          }
324          Declare->eraseFromParent();
325        }
326      }
327    }
328  }
329
330
331//===----------------------------------------------------------------------===//
332//                          BitcodeReaderValueList Class
333//===----------------------------------------------------------------------===//
334
335class BitcodeReaderValueList {
336  std::vector<WeakVH> ValuePtrs;
337
338  /// ResolveConstants - As we resolve forward-referenced constants, we add
339  /// information about them to this vector.  This allows us to resolve them in
340  /// bulk instead of resolving each reference at a time.  See the code in
341  /// ResolveConstantForwardRefs for more information about this.
342  ///
343  /// The key of this vector is the placeholder constant, the value is the slot
344  /// number that holds the resolved value.
345  typedef std::vector<std::pair<Constant*, unsigned> > ResolveConstantsTy;
346  ResolveConstantsTy ResolveConstants;
347  LLVMContext &Context;
348public:
349  BitcodeReaderValueList(LLVMContext &C) : Context(C) {}
350  ~BitcodeReaderValueList() {
351    assert(ResolveConstants.empty() && "Constants not resolved?");
352  }
353
354  // vector compatibility methods
355  unsigned size() const { return ValuePtrs.size(); }
356  void resize(unsigned N) { ValuePtrs.resize(N); }
357  void push_back(Value *V) {
358    ValuePtrs.push_back(V);
359  }
360
361  void clear() {
362    assert(ResolveConstants.empty() && "Constants not resolved?");
363    ValuePtrs.clear();
364  }
365
366  Value *operator[](unsigned i) const {
367    assert(i < ValuePtrs.size());
368    return ValuePtrs[i];
369  }
370
371  Value *back() const { return ValuePtrs.back(); }
372    void pop_back() { ValuePtrs.pop_back(); }
373  bool empty() const { return ValuePtrs.empty(); }
374  void shrinkTo(unsigned N) {
375    assert(N <= size() && "Invalid shrinkTo request!");
376    ValuePtrs.resize(N);
377  }
378
379  Constant *getConstantFwdRef(unsigned Idx, Type *Ty);
380  Value *getValueFwdRef(unsigned Idx, Type *Ty);
381
382  void AssignValue(Value *V, unsigned Idx);
383
384  /// ResolveConstantForwardRefs - Once all constants are read, this method bulk
385  /// resolves any forward references.
386  void ResolveConstantForwardRefs();
387};
388
389
390//===----------------------------------------------------------------------===//
391//                          BitcodeReaderMDValueList Class
392//===----------------------------------------------------------------------===//
393
394class BitcodeReaderMDValueList {
395  unsigned NumFwdRefs;
396  bool AnyFwdRefs;
397  std::vector<TrackingMDRef> MDValuePtrs;
398
399  LLVMContext &Context;
400public:
401  BitcodeReaderMDValueList(LLVMContext &C)
402      : NumFwdRefs(0), AnyFwdRefs(false), Context(C) {}
403
404  // vector compatibility methods
405  unsigned size() const       { return MDValuePtrs.size(); }
406  void resize(unsigned N)     { MDValuePtrs.resize(N); }
407  void push_back(Metadata *MD) { MDValuePtrs.emplace_back(MD); }
408  void clear()                { MDValuePtrs.clear();  }
409  Metadata *back() const      { return MDValuePtrs.back(); }
410  void pop_back()             { MDValuePtrs.pop_back(); }
411  bool empty() const          { return MDValuePtrs.empty(); }
412
413  Metadata *operator[](unsigned i) const {
414    assert(i < MDValuePtrs.size());
415    return MDValuePtrs[i];
416  }
417
418  void shrinkTo(unsigned N) {
419    assert(N <= size() && "Invalid shrinkTo request!");
420    MDValuePtrs.resize(N);
421  }
422
423  Metadata *getValueFwdRef(unsigned Idx);
424  void AssignValue(Metadata *MD, unsigned Idx);
425  void tryToResolveCycles();
426};
427
428class BitcodeReader : public GVMaterializer {
429  LLVMContext &Context;
430  DiagnosticHandlerFunction DiagnosticHandler;
431  Module *TheModule;
432  std::unique_ptr<MemoryBuffer> Buffer;
433  std::unique_ptr<BitstreamReader> StreamFile;
434  BitstreamCursor Stream;
435  DataStreamer *LazyStreamer;
436  uint64_t NextUnreadBit;
437  bool SeenValueSymbolTable;
438
439  std::vector<Type*> TypeList;
440  BitcodeReaderValueList ValueList;
441  BitcodeReaderMDValueList MDValueList;
442  SmallVector<Instruction *, 64> InstructionList;
443
444  std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInits;
445  std::vector<std::pair<GlobalAlias*, unsigned> > AliasInits;
446
447  /// MAttributes - The set of attributes by index.  Index zero in the
448  /// file is for null, and is thus not represented here.  As such all indices
449  /// are off by one.
450  std::vector<AttributeSet> MAttributes;
451
452  /// \brief The set of attribute groups.
453  std::map<unsigned, AttributeSet> MAttributeGroups;
454
455  /// FunctionBBs - While parsing a function body, this is a list of the basic
456  /// blocks for the function.
457  std::vector<BasicBlock*> FunctionBBs;
458
459  // When reading the module header, this list is populated with functions that
460  // have bodies later in the file.
461  std::vector<Function*> FunctionsWithBodies;
462
463  // When intrinsic functions are encountered which require upgrading they are
464  // stored here with their replacement function.
465  typedef std::vector<std::pair<Function*, Function*> > UpgradedIntrinsicMap;
466  UpgradedIntrinsicMap UpgradedIntrinsics;
467
468  // Map the bitcode's custom MDKind ID to the Module's MDKind ID.
469  DenseMap<unsigned, unsigned> MDKindMap;
470
471  // Several operations happen after the module header has been read, but
472  // before function bodies are processed. This keeps track of whether
473  // we've done this yet.
474  bool SeenFirstFunctionBody;
475
476  /// DeferredFunctionInfo - When function bodies are initially scanned, this
477  /// map contains info about where to find deferred function body in the
478  /// stream.
479  DenseMap<Function*, uint64_t> DeferredFunctionInfo;
480
481  /// BlockAddrFwdRefs - These are blockaddr references to basic blocks.  These
482  /// are resolved lazily when functions are loaded.
483  typedef std::pair<unsigned, GlobalVariable*> BlockAddrRefTy;
484  DenseMap<Function*, std::vector<BlockAddrRefTy> > BlockAddrFwdRefs;
485
486  static const std::error_category &BitcodeErrorCategory();
487
488public:
489  std::error_code Error(BitcodeError E, const Twine &Message);
490  std::error_code Error(BitcodeError E);
491  std::error_code Error(const Twine &Message);
492
493  explicit BitcodeReader(MemoryBuffer *buffer, LLVMContext &C,
494                         DiagnosticHandlerFunction DiagnosticHandler);
495  ~BitcodeReader() { FreeState(); }
496
497  void FreeState();
498
499  void releaseBuffer();
500
501  bool isDematerializable(const GlobalValue *GV) const override;
502  std::error_code materialize(GlobalValue *GV) override;
503  std::error_code MaterializeModule(Module *M) override;
504  std::vector<StructType *> getIdentifiedStructTypes() const override;
505  void Dematerialize(GlobalValue *GV) override;
506
507  /// @brief Main interface to parsing a bitcode buffer.
508  /// @returns true if an error occurred.
509  std::error_code ParseBitcodeInto(Module *M);
510
511  /// @brief Cheap mechanism to just extract module triple
512  /// @returns true if an error occurred.
513  llvm::ErrorOr<std::string> parseTriple();
514
515  static uint64_t decodeSignRotatedValue(uint64_t V);
516
517  /// Materialize any deferred Metadata block.
518  std::error_code materializeMetadata() override;
519
520  void setStripDebugInfo() override;
521
522private:
523  std::vector<StructType *> IdentifiedStructTypes;
524  StructType *createIdentifiedStructType(LLVMContext &Context, StringRef Name);
525  StructType *createIdentifiedStructType(LLVMContext &Context);
526
527  Type *getTypeByID(unsigned ID);
528  Type *getTypeByIDOrNull(unsigned ID);
529  Value *getFnValueByID(unsigned ID, Type *Ty) {
530    if (Ty && Ty->isMetadataTy())
531      return MetadataAsValue::get(Ty->getContext(), getFnMetadataByID(ID));
532    return ValueList.getValueFwdRef(ID, Ty);
533  }
534  Metadata *getFnMetadataByID(unsigned ID) {
535    return MDValueList.getValueFwdRef(ID);
536  }
537  BasicBlock *getBasicBlock(unsigned ID) const {
538    if (ID >= FunctionBBs.size()) return nullptr; // Invalid ID
539    return FunctionBBs[ID];
540  }
541  AttributeSet getAttributes(unsigned i) const {
542    if (i-1 < MAttributes.size())
543      return MAttributes[i-1];
544    return AttributeSet();
545  }
546
547  /// getValueTypePair - Read a value/type pair out of the specified record from
548  /// slot 'Slot'.  Increment Slot past the number of slots used in the record.
549  /// Return true on failure.
550  bool getValueTypePair(SmallVectorImpl<uint64_t> &Record, unsigned &Slot,
551                        unsigned InstNum, Value *&ResVal) {
552    if (Slot == Record.size()) return true;
553    unsigned ValNo = (unsigned)Record[Slot++];
554    if (ValNo < InstNum) {
555      // If this is not a forward reference, just return the value we already
556      // have.
557      ResVal = getFnValueByID(ValNo, nullptr);
558      return ResVal == nullptr;
559    } else if (Slot == Record.size()) {
560      return true;
561    }
562
563    unsigned TypeNo = (unsigned)Record[Slot++];
564    ResVal = getFnValueByID(ValNo, getTypeByID(TypeNo));
565    return ResVal == nullptr;
566  }
567  bool getValue(SmallVector<uint64_t, 64> &Record, unsigned &Slot,
568                Type *Ty, Value *&ResVal) {
569    if (Slot == Record.size()) return true;
570    unsigned ValNo = (unsigned)Record[Slot++];
571    ResVal = getFnValueByID(ValNo, Ty);
572    return ResVal == 0;
573  }
574
575
576  std::error_code ParseModule(bool Resume);
577  std::error_code ParseAttributeBlock();
578  std::error_code ParseTypeTable();
579  std::error_code ParseOldTypeTable();         // FIXME: Remove in LLVM 3.1
580  std::error_code ParseTypeTableBody();
581
582  std::error_code ParseOldTypeSymbolTable();   // FIXME: Remove in LLVM 3.1
583  std::error_code ParseValueSymbolTable();
584  std::error_code ParseConstants();
585  std::error_code RememberAndSkipFunctionBody();
586  std::error_code ParseFunctionBody(Function *F);
587  std::error_code GlobalCleanup();
588  std::error_code ResolveGlobalAndAliasInits();
589  std::error_code ParseMetadata();
590  std::error_code ParseMetadataAttachment();
591  llvm::ErrorOr<std::string> parseModuleTriple();
592  std::error_code InitStream();
593  std::error_code InitStreamFromBuffer();
594  std::error_code InitLazyStream();
595};
596
597} // end anonymous namespace
598
599static std::error_code Error(DiagnosticHandlerFunction DiagnosticHandler,
600                             std::error_code EC, const Twine &Message) {
601  BitcodeDiagnosticInfo DI(EC, DS_Error, Message);
602  DiagnosticHandler(DI);
603  return EC;
604}
605
606static std::error_code Error(DiagnosticHandlerFunction DiagnosticHandler,
607                             std::error_code EC) {
608  return Error(DiagnosticHandler, EC, EC.message());
609}
610
611std::error_code BitcodeReader::Error(BitcodeError E, const Twine &Message) {
612  return ::Error(DiagnosticHandler, make_error_code(E), Message);
613}
614
615std::error_code BitcodeReader::Error(const Twine &Message) {
616  return ::Error(DiagnosticHandler,
617                 make_error_code(BitcodeError::CorruptedBitcode), Message);
618}
619
620std::error_code BitcodeReader::Error(BitcodeError E) {
621  return ::Error(DiagnosticHandler, make_error_code(E));
622}
623
624static DiagnosticHandlerFunction getDiagHandler(DiagnosticHandlerFunction F,
625                                                LLVMContext &C) {
626  if (F)
627    return F;
628  return [&C](const DiagnosticInfo &DI) { C.diagnose(DI); };
629}
630
631BitcodeReader::BitcodeReader(MemoryBuffer *buffer, LLVMContext &C,
632                             DiagnosticHandlerFunction DiagnosticHandler)
633    : Context(C), DiagnosticHandler(getDiagHandler(DiagnosticHandler, C)),
634      TheModule(nullptr), Buffer(buffer), LazyStreamer(nullptr),
635      NextUnreadBit(0), SeenValueSymbolTable(false), ValueList(C),
636      MDValueList(C), SeenFirstFunctionBody(false) {}
637
638
639void BitcodeReader::FreeState() {
640  Buffer = nullptr;
641  std::vector<Type*>().swap(TypeList);
642  ValueList.clear();
643  MDValueList.clear();
644
645  std::vector<AttributeSet>().swap(MAttributes);
646  std::vector<BasicBlock*>().swap(FunctionBBs);
647  std::vector<Function*>().swap(FunctionsWithBodies);
648  DeferredFunctionInfo.clear();
649  MDKindMap.clear();
650}
651
652//===----------------------------------------------------------------------===//
653//  Helper functions to implement forward reference resolution, etc.
654//===----------------------------------------------------------------------===//
655
656/// ConvertToString - Convert a string from a record into an std::string, return
657/// true on failure.
658template<typename StrTy>
659static bool ConvertToString(ArrayRef<uint64_t> Record, unsigned Idx,
660                            StrTy &Result) {
661  if (Idx > Record.size())
662    return true;
663
664  for (unsigned i = Idx, e = Record.size(); i != e; ++i)
665    Result += (char)Record[i];
666  return false;
667}
668
669static GlobalValue::LinkageTypes getDecodedLinkage(unsigned Val) {
670  switch (Val) {
671  default: // Map unknown/new linkages to external
672  case 0:
673    return GlobalValue::ExternalLinkage;
674  case 1:
675    return GlobalValue::WeakAnyLinkage;
676  case 2:
677    return GlobalValue::AppendingLinkage;
678  case 3:
679    return GlobalValue::InternalLinkage;
680  case 4:
681    return GlobalValue::LinkOnceAnyLinkage;
682  case 5:
683    return GlobalValue::ExternalLinkage; // Obsolete DLLImportLinkage
684  case 6:
685    return GlobalValue::ExternalLinkage; // Obsolete DLLExportLinkage
686  case 7:
687    return GlobalValue::ExternalWeakLinkage;
688  case 8:
689    return GlobalValue::CommonLinkage;
690  case 9:
691    return GlobalValue::PrivateLinkage;
692  case 10:
693    return GlobalValue::WeakODRLinkage;
694  case 11:
695    return GlobalValue::LinkOnceODRLinkage;
696  case 12:
697    return GlobalValue::AvailableExternallyLinkage;
698  case 13:
699    return GlobalValue::PrivateLinkage; // Obsolete LinkerPrivateLinkage
700  case 14:
701    return GlobalValue::ExternalWeakLinkage; // Obsolete LinkerPrivateWeakLinkage
702  //ANDROID: convert LinkOnceODRAutoHideLinkage -> LinkOnceODRLinkage
703  case 15:
704    return GlobalValue::LinkOnceODRLinkage;
705  }
706}
707
708static GlobalValue::VisibilityTypes GetDecodedVisibility(unsigned Val) {
709  switch (Val) {
710  default: // Map unknown visibilities to default.
711  case 0: return GlobalValue::DefaultVisibility;
712  case 1: return GlobalValue::HiddenVisibility;
713  case 2: return GlobalValue::ProtectedVisibility;
714  }
715}
716
717static GlobalVariable::ThreadLocalMode GetDecodedThreadLocalMode(unsigned Val) {
718  switch (Val) {
719    case 0: return GlobalVariable::NotThreadLocal;
720    default: // Map unknown non-zero value to general dynamic.
721    case 1: return GlobalVariable::GeneralDynamicTLSModel;
722    case 2: return GlobalVariable::LocalDynamicTLSModel;
723    case 3: return GlobalVariable::InitialExecTLSModel;
724    case 4: return GlobalVariable::LocalExecTLSModel;
725  }
726}
727
728static int GetDecodedCastOpcode(unsigned Val) {
729  switch (Val) {
730  default: return -1;
731  case bitc::CAST_TRUNC   : return Instruction::Trunc;
732  case bitc::CAST_ZEXT    : return Instruction::ZExt;
733  case bitc::CAST_SEXT    : return Instruction::SExt;
734  case bitc::CAST_FPTOUI  : return Instruction::FPToUI;
735  case bitc::CAST_FPTOSI  : return Instruction::FPToSI;
736  case bitc::CAST_UITOFP  : return Instruction::UIToFP;
737  case bitc::CAST_SITOFP  : return Instruction::SIToFP;
738  case bitc::CAST_FPTRUNC : return Instruction::FPTrunc;
739  case bitc::CAST_FPEXT   : return Instruction::FPExt;
740  case bitc::CAST_PTRTOINT: return Instruction::PtrToInt;
741  case bitc::CAST_INTTOPTR: return Instruction::IntToPtr;
742  case bitc::CAST_BITCAST : return Instruction::BitCast;
743  }
744}
745static int GetDecodedBinaryOpcode(unsigned Val, Type *Ty) {
746  switch (Val) {
747  default: return -1;
748  case bitc::BINOP_ADD:
749    return Ty->isFPOrFPVectorTy() ? Instruction::FAdd : Instruction::Add;
750  case bitc::BINOP_SUB:
751    return Ty->isFPOrFPVectorTy() ? Instruction::FSub : Instruction::Sub;
752  case bitc::BINOP_MUL:
753    return Ty->isFPOrFPVectorTy() ? Instruction::FMul : Instruction::Mul;
754  case bitc::BINOP_UDIV: return Instruction::UDiv;
755  case bitc::BINOP_SDIV:
756    return Ty->isFPOrFPVectorTy() ? Instruction::FDiv : Instruction::SDiv;
757  case bitc::BINOP_UREM: return Instruction::URem;
758  case bitc::BINOP_SREM:
759    return Ty->isFPOrFPVectorTy() ? Instruction::FRem : Instruction::SRem;
760  case bitc::BINOP_SHL:  return Instruction::Shl;
761  case bitc::BINOP_LSHR: return Instruction::LShr;
762  case bitc::BINOP_ASHR: return Instruction::AShr;
763  case bitc::BINOP_AND:  return Instruction::And;
764  case bitc::BINOP_OR:   return Instruction::Or;
765  case bitc::BINOP_XOR:  return Instruction::Xor;
766  }
767}
768
769static AtomicRMWInst::BinOp GetDecodedRMWOperation(unsigned Val) {
770  switch (Val) {
771  default: return AtomicRMWInst::BAD_BINOP;
772  case bitc::RMW_XCHG: return AtomicRMWInst::Xchg;
773  case bitc::RMW_ADD: return AtomicRMWInst::Add;
774  case bitc::RMW_SUB: return AtomicRMWInst::Sub;
775  case bitc::RMW_AND: return AtomicRMWInst::And;
776  case bitc::RMW_NAND: return AtomicRMWInst::Nand;
777  case bitc::RMW_OR: return AtomicRMWInst::Or;
778  case bitc::RMW_XOR: return AtomicRMWInst::Xor;
779  case bitc::RMW_MAX: return AtomicRMWInst::Max;
780  case bitc::RMW_MIN: return AtomicRMWInst::Min;
781  case bitc::RMW_UMAX: return AtomicRMWInst::UMax;
782  case bitc::RMW_UMIN: return AtomicRMWInst::UMin;
783  }
784}
785
786static AtomicOrdering GetDecodedOrdering(unsigned Val) {
787  switch (Val) {
788  case bitc::ORDERING_NOTATOMIC: return NotAtomic;
789  case bitc::ORDERING_UNORDERED: return Unordered;
790  case bitc::ORDERING_MONOTONIC: return Monotonic;
791  case bitc::ORDERING_ACQUIRE: return Acquire;
792  case bitc::ORDERING_RELEASE: return Release;
793  case bitc::ORDERING_ACQREL: return AcquireRelease;
794  default: // Map unknown orderings to sequentially-consistent.
795  case bitc::ORDERING_SEQCST: return SequentiallyConsistent;
796  }
797}
798
799static SynchronizationScope GetDecodedSynchScope(unsigned Val) {
800  switch (Val) {
801  case bitc::SYNCHSCOPE_SINGLETHREAD: return SingleThread;
802  default: // Map unknown scopes to cross-thread.
803  case bitc::SYNCHSCOPE_CROSSTHREAD: return CrossThread;
804  }
805}
806
807namespace llvm {
808namespace {
809  /// @brief A class for maintaining the slot number definition
810  /// as a placeholder for the actual definition for forward constants defs.
811  class ConstantPlaceHolder : public ConstantExpr {
812    void operator=(const ConstantPlaceHolder &) = delete;
813  public:
814    // allocate space for exactly one operand
815    void *operator new(size_t s) {
816      return User::operator new(s, 1);
817    }
818    explicit ConstantPlaceHolder(Type *Ty, LLVMContext& Context)
819      : ConstantExpr(Ty, Instruction::UserOp1, &Op<0>(), 1) {
820      Op<0>() = UndefValue::get(Type::getInt32Ty(Context));
821    }
822
823    /// @brief Methods to support type inquiry through isa, cast, and dyn_cast.
824    static bool classof(const Value *V) {
825      return isa<ConstantExpr>(V) &&
826             cast<ConstantExpr>(V)->getOpcode() == Instruction::UserOp1;
827    }
828
829
830    /// Provide fast operand accessors
831    DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
832  };
833}
834
835// FIXME: can we inherit this from ConstantExpr?
836template <>
837struct OperandTraits<ConstantPlaceHolder> :
838  public FixedNumOperandTraits<ConstantPlaceHolder, 1> {
839};
840DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ConstantPlaceHolder, Value)
841}
842
843
844void BitcodeReaderValueList::AssignValue(Value *V, unsigned Idx) {
845  if (Idx == size()) {
846    push_back(V);
847    return;
848  }
849
850  if (Idx >= size())
851    resize(Idx+1);
852
853  WeakVH &OldV = ValuePtrs[Idx];
854  if (!OldV) {
855    OldV = V;
856    return;
857  }
858
859  // Handle constants and non-constants (e.g. instrs) differently for
860  // efficiency.
861  if (Constant *PHC = dyn_cast<Constant>(&*OldV)) {
862    ResolveConstants.push_back(std::make_pair(PHC, Idx));
863    OldV = V;
864  } else {
865    // If there was a forward reference to this value, replace it.
866    Value *PrevVal = OldV;
867    OldV->replaceAllUsesWith(V);
868    delete PrevVal;
869  }
870}
871
872
873Constant *BitcodeReaderValueList::getConstantFwdRef(unsigned Idx,
874                                                    Type *Ty) {
875  if (Idx >= size())
876    resize(Idx + 1);
877
878  if (Value *V = ValuePtrs[Idx]) {
879    assert(Ty == V->getType() && "Type mismatch in constant table!");
880    return cast<Constant>(V);
881  }
882
883  // Create and return a placeholder, which will later be RAUW'd.
884  Constant *C = new ConstantPlaceHolder(Ty, Context);
885  ValuePtrs[Idx] = C;
886  return C;
887}
888
889Value *BitcodeReaderValueList::getValueFwdRef(unsigned Idx, Type *Ty) {
890  if (Idx >= size())
891    resize(Idx + 1);
892
893  if (Value *V = ValuePtrs[Idx]) {
894    assert((!Ty || Ty == V->getType()) && "Type mismatch in value table!");
895    return V;
896  }
897
898  // No type specified, must be invalid reference.
899  if (!Ty) return nullptr;
900
901  // Create and return a placeholder, which will later be RAUW'd.
902  Value *V = new Argument(Ty);
903  ValuePtrs[Idx] = V;
904  return V;
905}
906
907/// ResolveConstantForwardRefs - Once all constants are read, this method bulk
908/// resolves any forward references.  The idea behind this is that we sometimes
909/// get constants (such as large arrays) which reference *many* forward ref
910/// constants.  Replacing each of these causes a lot of thrashing when
911/// building/reuniquing the constant.  Instead of doing this, we look at all the
912/// uses and rewrite all the place holders at once for any constant that uses
913/// a placeholder.
914void BitcodeReaderValueList::ResolveConstantForwardRefs() {
915  // Sort the values by-pointer so that they are efficient to look up with a
916  // binary search.
917  std::sort(ResolveConstants.begin(), ResolveConstants.end());
918
919  SmallVector<Constant*, 64> NewOps;
920
921  while (!ResolveConstants.empty()) {
922    Value *RealVal = operator[](ResolveConstants.back().second);
923    Constant *Placeholder = ResolveConstants.back().first;
924    ResolveConstants.pop_back();
925
926    // Loop over all users of the placeholder, updating them to reference the
927    // new value.  If they reference more than one placeholder, update them all
928    // at once.
929    while (!Placeholder->use_empty()) {
930      auto UI = Placeholder->user_begin();
931      User *U = *UI;
932
933      // If the using object isn't uniqued, just update the operands.  This
934      // handles instructions and initializers for global variables.
935      if (!isa<Constant>(U) || isa<GlobalValue>(U)) {
936        UI.getUse().set(RealVal);
937        continue;
938      }
939
940      // Otherwise, we have a constant that uses the placeholder.  Replace that
941      // constant with a new constant that has *all* placeholder uses updated.
942      Constant *UserC = cast<Constant>(U);
943      for (User::op_iterator I = UserC->op_begin(), E = UserC->op_end();
944           I != E; ++I) {
945        Value *NewOp;
946        if (!isa<ConstantPlaceHolder>(*I)) {
947          // Not a placeholder reference.
948          NewOp = *I;
949        } else if (*I == Placeholder) {
950          // Common case is that it just references this one placeholder.
951          NewOp = RealVal;
952        } else {
953          // Otherwise, look up the placeholder in ResolveConstants.
954          ResolveConstantsTy::iterator It =
955            std::lower_bound(ResolveConstants.begin(), ResolveConstants.end(),
956                             std::pair<Constant*, unsigned>(cast<Constant>(*I),
957                                                            0));
958          assert(It != ResolveConstants.end() && It->first == *I);
959          NewOp = operator[](It->second);
960        }
961
962        NewOps.push_back(cast<Constant>(NewOp));
963      }
964
965      // Make the new constant.
966      Constant *NewC;
967      if (ConstantArray *UserCA = dyn_cast<ConstantArray>(UserC)) {
968        NewC = ConstantArray::get(UserCA->getType(), NewOps);
969      } else if (ConstantStruct *UserCS = dyn_cast<ConstantStruct>(UserC)) {
970        NewC = ConstantStruct::get(UserCS->getType(), NewOps);
971      } else if (isa<ConstantVector>(UserC)) {
972        NewC = ConstantVector::get(NewOps);
973      } else {
974        assert(isa<ConstantExpr>(UserC) && "Must be a ConstantExpr.");
975        NewC = cast<ConstantExpr>(UserC)->getWithOperands(NewOps);
976      }
977
978      UserC->replaceAllUsesWith(NewC);
979      UserC->destroyConstant();
980      NewOps.clear();
981    }
982
983    // Update all ValueHandles, they should be the only users at this point.
984    Placeholder->replaceAllUsesWith(RealVal);
985    delete Placeholder;
986  }
987}
988
989void BitcodeReaderMDValueList::AssignValue(Metadata *MD, unsigned Idx) {
990  if (Idx == size()) {
991    push_back(MD);
992    return;
993  }
994
995  if (Idx >= size())
996    resize(Idx+1);
997
998  TrackingMDRef &OldMD = MDValuePtrs[Idx];
999  if (!OldMD) {
1000    OldMD.reset(MD);
1001    return;
1002  }
1003
1004  // If there was a forward reference to this value, replace it.
1005  TempMDTuple PrevMD(cast<MDTuple>(OldMD.get()));
1006  PrevMD->replaceAllUsesWith(MD);
1007  --NumFwdRefs;
1008}
1009
1010Metadata *BitcodeReaderMDValueList::getValueFwdRef(unsigned Idx) {
1011  if (Idx >= size())
1012    resize(Idx + 1);
1013
1014  if (Metadata *MD = MDValuePtrs[Idx])
1015    return MD;
1016
1017  // Create and return a placeholder, which will later be RAUW'd.
1018  AnyFwdRefs = true;
1019  ++NumFwdRefs;
1020  Metadata *MD = MDNode::getTemporary(Context, None).release();
1021  MDValuePtrs[Idx].reset(MD);
1022  return MD;
1023}
1024
1025void BitcodeReaderMDValueList::tryToResolveCycles() {
1026  if (!AnyFwdRefs)
1027    // Nothing to do.
1028    return;
1029
1030  if (NumFwdRefs)
1031    // Still forward references... can't resolve cycles.
1032    return;
1033
1034  // Resolve any cycles.
1035  for (auto &MD : MDValuePtrs) {
1036    auto *N = dyn_cast_or_null<MDNode>(MD);
1037    if (!N)
1038      continue;
1039
1040    assert(!N->isTemporary() && "Unexpected forward reference");
1041    N->resolveCycles();
1042  }
1043}
1044
1045Type *BitcodeReader::getTypeByID(unsigned ID) {
1046  // The type table size is always specified correctly.
1047  if (ID >= TypeList.size())
1048    return nullptr;
1049
1050  if (Type *Ty = TypeList[ID])
1051    return Ty;
1052
1053  // If we have a forward reference, the only possible case is when it is to a
1054  // named struct.  Just create a placeholder for now.
1055  return TypeList[ID] = createIdentifiedStructType(Context);
1056}
1057
1058StructType *BitcodeReader::createIdentifiedStructType(LLVMContext &Context,
1059                                                      StringRef Name) {
1060  auto *Ret = StructType::create(Context, Name);
1061  IdentifiedStructTypes.push_back(Ret);
1062  return Ret;
1063}
1064
1065StructType *BitcodeReader::createIdentifiedStructType(LLVMContext &Context) {
1066  auto *Ret = StructType::create(Context);
1067  IdentifiedStructTypes.push_back(Ret);
1068  return Ret;
1069}
1070
1071
1072/// FIXME: Remove in LLVM 3.1, only used by ParseOldTypeTable.
1073Type *BitcodeReader::getTypeByIDOrNull(unsigned ID) {
1074  if (ID >= TypeList.size())
1075    TypeList.resize(ID+1);
1076
1077  return TypeList[ID];
1078}
1079
1080//===----------------------------------------------------------------------===//
1081//  Functions for parsing blocks from the bitcode file
1082//===----------------------------------------------------------------------===//
1083
1084
1085/// \brief This fills an AttrBuilder object with the LLVM attributes that have
1086/// been decoded from the given integer. This function must stay in sync with
1087/// 'encodeLLVMAttributesForBitcode'.
1088static void decodeLLVMAttributesForBitcode(AttrBuilder &B,
1089                                           uint64_t EncodedAttrs) {
1090  // FIXME: Remove in 4.0.
1091
1092  // The alignment is stored as a 16-bit raw value from bits 31--16.  We shift
1093  // the bits above 31 down by 11 bits.
1094  unsigned Alignment = (EncodedAttrs & (0xffffULL << 16)) >> 16;
1095  assert((!Alignment || isPowerOf2_32(Alignment)) &&
1096         "Alignment must be a power of two.");
1097
1098  if (Alignment)
1099    B.addAlignmentAttr(Alignment);
1100  B.addRawValue(((EncodedAttrs & (0xfffffULL << 32)) >> 11) |
1101                (EncodedAttrs & 0xffff));
1102}
1103
1104std::error_code BitcodeReader::ParseAttributeBlock() {
1105  if (Stream.EnterSubBlock(bitc::PARAMATTR_BLOCK_ID))
1106    return Error("Invalid record");
1107
1108  if (!MAttributes.empty())
1109    return Error("Invalid multiple blocks");
1110
1111  SmallVector<uint64_t, 64> Record;
1112
1113  SmallVector<AttributeSet, 8> Attrs;
1114
1115  // Read all the records.
1116  while (1) {
1117    BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
1118
1119    switch (Entry.Kind) {
1120    case BitstreamEntry::SubBlock: // Handled for us already.
1121    case BitstreamEntry::Error:
1122      return Error("Malformed block");
1123    case BitstreamEntry::EndBlock:
1124      return std::error_code();
1125    case BitstreamEntry::Record:
1126      // The interesting case.
1127      break;
1128    }
1129
1130    // Read a record.
1131    Record.clear();
1132    switch (Stream.readRecord(Entry.ID, Record)) {
1133    default:  // Default behavior: ignore.
1134      break;
1135    case bitc::PARAMATTR_CODE_ENTRY_OLD: { // ENTRY: [paramidx0, attr0, ...]
1136      // FIXME: Remove in 4.0.
1137      if (Record.size() & 1)
1138        return Error("Invalid record");
1139
1140      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
1141        AttrBuilder B;
1142        decodeLLVMAttributesForBitcode(B, Record[i+1]);
1143        Attrs.push_back(AttributeSet::get(Context, Record[i], B));
1144      }
1145
1146      MAttributes.push_back(AttributeSet::get(Context, Attrs));
1147      Attrs.clear();
1148      break;
1149    }
1150    case bitc::PARAMATTR_CODE_ENTRY: { // ENTRY: [attrgrp0, attrgrp1, ...]
1151      for (unsigned i = 0, e = Record.size(); i != e; ++i)
1152        Attrs.push_back(MAttributeGroups[Record[i]]);
1153
1154      MAttributes.push_back(AttributeSet::get(Context, Attrs));
1155      Attrs.clear();
1156      break;
1157    }
1158    }
1159  }
1160}
1161
1162
1163std::error_code BitcodeReader::ParseTypeTable() {
1164  if (Stream.EnterSubBlock(bitc::TYPE_BLOCK_ID_NEW))
1165    return Error("Invalid record");
1166
1167  return ParseTypeTableBody();
1168}
1169
1170std::error_code BitcodeReader::ParseTypeTableBody() {
1171  if (!TypeList.empty())
1172    return Error("Invalid multiple blocks");
1173
1174  SmallVector<uint64_t, 64> Record;
1175  unsigned NumRecords = 0;
1176
1177  SmallString<64> TypeName;
1178
1179  // Read all the records for this type table.
1180  while (1) {
1181    BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
1182
1183    switch (Entry.Kind) {
1184    case BitstreamEntry::SubBlock: // Handled for us already.
1185    case BitstreamEntry::Error:
1186      return Error("Malformed block");
1187    case BitstreamEntry::EndBlock:
1188      if (NumRecords != TypeList.size())
1189        return Error("Malformed block");
1190      return std::error_code();
1191    case BitstreamEntry::Record:
1192      // The interesting case.
1193      break;
1194    }
1195
1196    // Read a record.
1197    Record.clear();
1198    Type *ResultTy = nullptr;
1199    switch (Stream.readRecord(Entry.ID, Record)) {
1200    default:
1201      return Error("Invalid value");
1202    case bitc::TYPE_CODE_NUMENTRY: // TYPE_CODE_NUMENTRY: [numentries]
1203      // TYPE_CODE_NUMENTRY contains a count of the number of types in the
1204      // type list.  This allows us to reserve space.
1205      if (Record.size() < 1)
1206        return Error("Invalid record");
1207      TypeList.resize(Record[0]);
1208      continue;
1209    case bitc::TYPE_CODE_VOID:      // VOID
1210      ResultTy = Type::getVoidTy(Context);
1211      break;
1212    case bitc::TYPE_CODE_HALF:     // HALF
1213      ResultTy = Type::getHalfTy(Context);
1214      break;
1215    case bitc::TYPE_CODE_FLOAT:     // FLOAT
1216      ResultTy = Type::getFloatTy(Context);
1217      break;
1218    case bitc::TYPE_CODE_DOUBLE:    // DOUBLE
1219      ResultTy = Type::getDoubleTy(Context);
1220      break;
1221    case bitc::TYPE_CODE_X86_FP80:  // X86_FP80
1222      ResultTy = Type::getX86_FP80Ty(Context);
1223      break;
1224    case bitc::TYPE_CODE_FP128:     // FP128
1225      ResultTy = Type::getFP128Ty(Context);
1226      break;
1227    case bitc::TYPE_CODE_PPC_FP128: // PPC_FP128
1228      ResultTy = Type::getPPC_FP128Ty(Context);
1229      break;
1230    case bitc::TYPE_CODE_LABEL:     // LABEL
1231      ResultTy = Type::getLabelTy(Context);
1232      break;
1233    case bitc::TYPE_CODE_METADATA:  // METADATA
1234      ResultTy = Type::getMetadataTy(Context);
1235      break;
1236    case bitc::TYPE_CODE_X86_MMX:   // X86_MMX
1237      ResultTy = Type::getX86_MMXTy(Context);
1238      break;
1239    case bitc::TYPE_CODE_INTEGER:   // INTEGER: [width]
1240      if (Record.size() < 1)
1241        return Error("Invalid record");
1242
1243      ResultTy = IntegerType::get(Context, Record[0]);
1244      break;
1245    case bitc::TYPE_CODE_POINTER: { // POINTER: [pointee type] or
1246                                    //          [pointee type, address space]
1247      if (Record.size() < 1)
1248        return Error("Invalid record");
1249      unsigned AddressSpace = 0;
1250      if (Record.size() == 2)
1251        AddressSpace = Record[1];
1252      ResultTy = getTypeByID(Record[0]);
1253      if (!ResultTy)
1254        return Error("Invalid type");
1255      ResultTy = PointerType::get(ResultTy, AddressSpace);
1256      break;
1257    }
1258    case bitc::TYPE_CODE_FUNCTION_OLD: {
1259      // FIXME: attrid is dead, remove it in LLVM 4.0
1260      // FUNCTION: [vararg, attrid, retty, paramty x N]
1261      if (Record.size() < 3)
1262        return Error("Invalid record");
1263      SmallVector<Type*, 8> ArgTys;
1264      for (unsigned i = 3, e = Record.size(); i != e; ++i) {
1265        if (Type *T = getTypeByID(Record[i]))
1266          ArgTys.push_back(T);
1267        else
1268          break;
1269      }
1270
1271      ResultTy = getTypeByID(Record[2]);
1272      if (!ResultTy || ArgTys.size() < Record.size()-3)
1273        return Error("Invalid type");
1274
1275      ResultTy = FunctionType::get(ResultTy, ArgTys, Record[0]);
1276      break;
1277    }
1278    case bitc::TYPE_CODE_FUNCTION: {
1279      // FUNCTION: [vararg, retty, paramty x N]
1280      if (Record.size() < 2)
1281        return Error("Invalid record");
1282      SmallVector<Type*, 8> ArgTys;
1283      for (unsigned i = 2, e = Record.size(); i != e; ++i) {
1284        if (Type *T = getTypeByID(Record[i]))
1285          ArgTys.push_back(T);
1286        else
1287          break;
1288      }
1289
1290      ResultTy = getTypeByID(Record[1]);
1291      if (!ResultTy || ArgTys.size() < Record.size()-2)
1292        return Error("Invalid type");
1293
1294      ResultTy = FunctionType::get(ResultTy, ArgTys, Record[0]);
1295      break;
1296    }
1297    case bitc::TYPE_CODE_STRUCT_ANON: {  // STRUCT: [ispacked, eltty x N]
1298      if (Record.size() < 1)
1299        return Error("Invalid record");
1300      SmallVector<Type*, 8> EltTys;
1301      for (unsigned i = 1, e = Record.size(); i != e; ++i) {
1302        if (Type *T = getTypeByID(Record[i]))
1303          EltTys.push_back(T);
1304        else
1305          break;
1306      }
1307      if (EltTys.size() != Record.size()-1)
1308        return Error("Invalid type");
1309      ResultTy = StructType::get(Context, EltTys, Record[0]);
1310      break;
1311    }
1312    case bitc::TYPE_CODE_STRUCT_NAME:   // STRUCT_NAME: [strchr x N]
1313      if (ConvertToString(Record, 0, TypeName))
1314        return Error("Invalid record");
1315      continue;
1316
1317    case bitc::TYPE_CODE_STRUCT_NAMED: { // STRUCT: [ispacked, eltty x N]
1318      if (Record.size() < 1)
1319        return Error("Invalid record");
1320
1321      if (NumRecords >= TypeList.size())
1322        return Error("Invalid TYPE table");
1323
1324      // Check to see if this was forward referenced, if so fill in the temp.
1325      StructType *Res = cast_or_null<StructType>(TypeList[NumRecords]);
1326      if (Res) {
1327        Res->setName(TypeName);
1328        TypeList[NumRecords] = nullptr;
1329      } else  // Otherwise, create a new struct.
1330        Res = createIdentifiedStructType(Context, TypeName);
1331      TypeName.clear();
1332
1333      SmallVector<Type*, 8> EltTys;
1334      for (unsigned i = 1, e = Record.size(); i != e; ++i) {
1335        if (Type *T = getTypeByID(Record[i]))
1336          EltTys.push_back(T);
1337        else
1338          break;
1339      }
1340      if (EltTys.size() != Record.size()-1)
1341        return Error("Invalid record");
1342      Res->setBody(EltTys, Record[0]);
1343      ResultTy = Res;
1344      break;
1345    }
1346    case bitc::TYPE_CODE_OPAQUE: {       // OPAQUE: []
1347      if (Record.size() != 1)
1348        return Error("Invalid record");
1349
1350      if (NumRecords >= TypeList.size())
1351        return Error("Invalid TYPE table");
1352
1353      // Check to see if this was forward referenced, if so fill in the temp.
1354      StructType *Res = cast_or_null<StructType>(TypeList[NumRecords]);
1355      if (Res) {
1356        Res->setName(TypeName);
1357        TypeList[NumRecords] = nullptr;
1358      } else  // Otherwise, create a new struct with no body.
1359        Res = createIdentifiedStructType(Context, TypeName);
1360      TypeName.clear();
1361      ResultTy = Res;
1362      break;
1363    }
1364    case bitc::TYPE_CODE_ARRAY:     // ARRAY: [numelts, eltty]
1365      if (Record.size() < 2)
1366        return Error("Invalid record");
1367      if ((ResultTy = getTypeByID(Record[1])))
1368        ResultTy = ArrayType::get(ResultTy, Record[0]);
1369      else
1370        return Error("Invalid type");
1371      break;
1372    case bitc::TYPE_CODE_VECTOR:    // VECTOR: [numelts, eltty]
1373      if (Record.size() < 2)
1374        return Error("Invalid record");
1375      if ((ResultTy = getTypeByID(Record[1])))
1376        ResultTy = VectorType::get(ResultTy, Record[0]);
1377      else
1378        return Error("Invalid type");
1379      break;
1380    }
1381
1382    if (NumRecords >= TypeList.size())
1383      return Error("Invalid TYPE table");
1384    assert(ResultTy && "Didn't read a type?");
1385    assert(!TypeList[NumRecords] && "Already read type?");
1386    TypeList[NumRecords++] = ResultTy;
1387  }
1388}
1389
1390// FIXME: Remove in LLVM 3.1
1391std::error_code BitcodeReader::ParseOldTypeTable() {
1392  if (Stream.EnterSubBlock(TYPE_BLOCK_ID_OLD_3_0))
1393    return Error("Malformed block");
1394
1395  if (!TypeList.empty())
1396    return Error("Invalid TYPE table");
1397
1398
1399  // While horrible, we have no good ordering of types in the bc file.  Just
1400  // iteratively parse types out of the bc file in multiple passes until we get
1401  // them all.  Do this by saving a cursor for the start of the type block.
1402  BitstreamCursor StartOfTypeBlockCursor(Stream);
1403
1404  unsigned NumTypesRead = 0;
1405
1406  SmallVector<uint64_t, 64> Record;
1407RestartScan:
1408  unsigned NextTypeID = 0;
1409  bool ReadAnyTypes = false;
1410
1411  // Read all the records for this type table.
1412  while (1) {
1413    unsigned Code = Stream.ReadCode();
1414    if (Code == bitc::END_BLOCK) {
1415      if (NextTypeID != TypeList.size())
1416        return Error("Invalid TYPE table");
1417
1418      // If we haven't read all of the types yet, iterate again.
1419      if (NumTypesRead != TypeList.size()) {
1420        // If we didn't successfully read any types in this pass, then we must
1421        // have an unhandled forward reference.
1422        if (!ReadAnyTypes)
1423          return Error("Invalid TYPE table");
1424
1425        Stream = StartOfTypeBlockCursor;
1426        goto RestartScan;
1427      }
1428
1429      if (Stream.ReadBlockEnd())
1430        return Error("Invalid TYPE table");
1431      return std::error_code();
1432    }
1433
1434    if (Code == bitc::ENTER_SUBBLOCK) {
1435      // No known subblocks, always skip them.
1436      Stream.ReadSubBlockID();
1437      if (Stream.SkipBlock())
1438        return Error("Malformed block");
1439      continue;
1440    }
1441
1442    if (Code == bitc::DEFINE_ABBREV) {
1443      Stream.ReadAbbrevRecord();
1444      continue;
1445    }
1446
1447    // Read a record.
1448    Record.clear();
1449    Type *ResultTy = nullptr;
1450    switch (Stream.readRecord(Code, Record)) {
1451    default: return Error("Invalid TYPE table");
1452    case bitc::TYPE_CODE_NUMENTRY: // TYPE_CODE_NUMENTRY: [numentries]
1453      // TYPE_CODE_NUMENTRY contains a count of the number of types in the
1454      // type list.  This allows us to reserve space.
1455      if (Record.size() < 1)
1456        return Error("Invalid TYPE table");
1457      TypeList.resize(Record[0]);
1458      continue;
1459    case bitc::TYPE_CODE_VOID:      // VOID
1460      ResultTy = Type::getVoidTy(Context);
1461      break;
1462    case bitc::TYPE_CODE_FLOAT:     // FLOAT
1463      ResultTy = Type::getFloatTy(Context);
1464      break;
1465    case bitc::TYPE_CODE_DOUBLE:    // DOUBLE
1466      ResultTy = Type::getDoubleTy(Context);
1467      break;
1468    case bitc::TYPE_CODE_X86_FP80:  // X86_FP80
1469      ResultTy = Type::getX86_FP80Ty(Context);
1470      break;
1471    case bitc::TYPE_CODE_FP128:     // FP128
1472      ResultTy = Type::getFP128Ty(Context);
1473      break;
1474    case bitc::TYPE_CODE_PPC_FP128: // PPC_FP128
1475      ResultTy = Type::getPPC_FP128Ty(Context);
1476      break;
1477    case bitc::TYPE_CODE_LABEL:     // LABEL
1478      ResultTy = Type::getLabelTy(Context);
1479      break;
1480    case bitc::TYPE_CODE_METADATA:  // METADATA
1481      ResultTy = Type::getMetadataTy(Context);
1482      break;
1483    case bitc::TYPE_CODE_X86_MMX:   // X86_MMX
1484      ResultTy = Type::getX86_MMXTy(Context);
1485      break;
1486    case bitc::TYPE_CODE_INTEGER:   // INTEGER: [width]
1487      if (Record.size() < 1)
1488        return Error("Invalid TYPE table");
1489      ResultTy = IntegerType::get(Context, Record[0]);
1490      break;
1491    case bitc::TYPE_CODE_OPAQUE:    // OPAQUE
1492      if (NextTypeID < TypeList.size() && TypeList[NextTypeID] == 0)
1493        ResultTy = StructType::create(Context, "");
1494      break;
1495    case TYPE_CODE_STRUCT_OLD_3_0: {// STRUCT_OLD
1496      if (NextTypeID >= TypeList.size()) break;
1497      // If we already read it, don't reprocess.
1498      if (TypeList[NextTypeID] &&
1499          !cast<StructType>(TypeList[NextTypeID])->isOpaque())
1500        break;
1501
1502      // Set a type.
1503      if (TypeList[NextTypeID] == 0)
1504        TypeList[NextTypeID] = StructType::create(Context, "");
1505
1506      std::vector<Type*> EltTys;
1507      for (unsigned i = 1, e = Record.size(); i != e; ++i) {
1508        if (Type *Elt = getTypeByIDOrNull(Record[i]))
1509          EltTys.push_back(Elt);
1510        else
1511          break;
1512      }
1513
1514      if (EltTys.size() != Record.size()-1)
1515        break;      // Not all elements are ready.
1516
1517      cast<StructType>(TypeList[NextTypeID])->setBody(EltTys, Record[0]);
1518      ResultTy = TypeList[NextTypeID];
1519      TypeList[NextTypeID] = 0;
1520      break;
1521    }
1522    case bitc::TYPE_CODE_POINTER: { // POINTER: [pointee type] or
1523      //          [pointee type, address space]
1524      if (Record.size() < 1)
1525        return Error("Invalid TYPE table");
1526      unsigned AddressSpace = 0;
1527      if (Record.size() == 2)
1528        AddressSpace = Record[1];
1529      if ((ResultTy = getTypeByIDOrNull(Record[0])))
1530        ResultTy = PointerType::get(ResultTy, AddressSpace);
1531      break;
1532    }
1533    case bitc::TYPE_CODE_FUNCTION_OLD: {
1534      // FIXME: attrid is dead, remove it in LLVM 3.0
1535      // FUNCTION: [vararg, attrid, retty, paramty x N]
1536      if (Record.size() < 3)
1537        return Error("Invalid TYPE table");
1538      std::vector<Type*> ArgTys;
1539      for (unsigned i = 3, e = Record.size(); i != e; ++i) {
1540        if (Type *Elt = getTypeByIDOrNull(Record[i]))
1541          ArgTys.push_back(Elt);
1542        else
1543          break;
1544      }
1545      if (ArgTys.size()+3 != Record.size())
1546        break;  // Something was null.
1547      if ((ResultTy = getTypeByIDOrNull(Record[2])))
1548        ResultTy = FunctionType::get(ResultTy, ArgTys, Record[0]);
1549      break;
1550    }
1551    case bitc::TYPE_CODE_FUNCTION: {
1552      // FUNCTION: [vararg, retty, paramty x N]
1553      if (Record.size() < 2)
1554        return Error("Invalid TYPE table");
1555      std::vector<Type*> ArgTys;
1556      for (unsigned i = 2, e = Record.size(); i != e; ++i) {
1557        if (Type *Elt = getTypeByIDOrNull(Record[i]))
1558          ArgTys.push_back(Elt);
1559        else
1560          break;
1561      }
1562      if (ArgTys.size()+2 != Record.size())
1563        break;  // Something was null.
1564      if ((ResultTy = getTypeByIDOrNull(Record[1])))
1565        ResultTy = FunctionType::get(ResultTy, ArgTys, Record[0]);
1566      break;
1567    }
1568    case bitc::TYPE_CODE_ARRAY:     // ARRAY: [numelts, eltty]
1569      if (Record.size() < 2)
1570        return Error("Invalid TYPE table");
1571      if ((ResultTy = getTypeByIDOrNull(Record[1])))
1572        ResultTy = ArrayType::get(ResultTy, Record[0]);
1573      break;
1574    case bitc::TYPE_CODE_VECTOR:    // VECTOR: [numelts, eltty]
1575      if (Record.size() < 2)
1576        return Error("Invalid TYPE table");
1577      if ((ResultTy = getTypeByIDOrNull(Record[1])))
1578        ResultTy = VectorType::get(ResultTy, Record[0]);
1579      break;
1580    }
1581
1582    if (NextTypeID >= TypeList.size())
1583      return Error("Invalid TYPE table");
1584
1585    if (ResultTy && TypeList[NextTypeID] == 0) {
1586      ++NumTypesRead;
1587      ReadAnyTypes = true;
1588
1589      TypeList[NextTypeID] = ResultTy;
1590    }
1591
1592    ++NextTypeID;
1593  }
1594}
1595
1596
1597std::error_code BitcodeReader::ParseOldTypeSymbolTable() {
1598  if (Stream.EnterSubBlock(TYPE_SYMTAB_BLOCK_ID_OLD_3_0))
1599    return Error("Malformed block");
1600
1601  SmallVector<uint64_t, 64> Record;
1602
1603  // Read all the records for this type table.
1604  std::string TypeName;
1605  while (1) {
1606    unsigned Code = Stream.ReadCode();
1607    if (Code == bitc::END_BLOCK) {
1608      if (Stream.ReadBlockEnd())
1609        return Error("Malformed block");
1610      return std::error_code();
1611    }
1612
1613    if (Code == bitc::ENTER_SUBBLOCK) {
1614      // No known subblocks, always skip them.
1615      Stream.ReadSubBlockID();
1616      if (Stream.SkipBlock())
1617        return Error("Malformed block");
1618      continue;
1619    }
1620
1621    if (Code == bitc::DEFINE_ABBREV) {
1622      Stream.ReadAbbrevRecord();
1623      continue;
1624    }
1625
1626    // Read a record.
1627    Record.clear();
1628    switch (Stream.readRecord(Code, Record)) {
1629    default:  // Default behavior: unknown type.
1630      break;
1631    case bitc::TST_CODE_ENTRY:    // TST_ENTRY: [typeid, namechar x N]
1632      if (ConvertToString(Record, 1, TypeName))
1633        return Error("Invalid record");
1634      unsigned TypeID = Record[0];
1635      if (TypeID >= TypeList.size())
1636        return Error("Invalid record");
1637
1638      // Only apply the type name to a struct type with no name.
1639      if (StructType *STy = dyn_cast<StructType>(TypeList[TypeID]))
1640        if (!STy->isLiteral() && !STy->hasName())
1641          STy->setName(TypeName);
1642      TypeName.clear();
1643      break;
1644    }
1645  }
1646}
1647
1648std::error_code BitcodeReader::ParseValueSymbolTable() {
1649  if (Stream.EnterSubBlock(bitc::VALUE_SYMTAB_BLOCK_ID))
1650    return Error("Invalid record");
1651
1652  SmallVector<uint64_t, 64> Record;
1653
1654  // Read all the records for this value table.
1655  SmallString<128> ValueName;
1656  while (1) {
1657    unsigned Code = Stream.ReadCode();
1658    if (Code == bitc::END_BLOCK) {
1659      if (Stream.ReadBlockEnd())
1660        return Error("Malformed block");
1661      return std::error_code();
1662    }
1663    if (Code == bitc::ENTER_SUBBLOCK) {
1664      // No known subblocks, always skip them.
1665      Stream.ReadSubBlockID();
1666      if (Stream.SkipBlock())
1667        return Error("Malformed block");
1668      continue;
1669    }
1670
1671    if (Code == bitc::DEFINE_ABBREV) {
1672      Stream.ReadAbbrevRecord();
1673      continue;
1674    }
1675
1676    // Read a record.
1677    Record.clear();
1678    switch (Stream.readRecord(Code, Record)) {
1679    default:  // Default behavior: unknown type.
1680      break;
1681    case bitc::VST_CODE_ENTRY: {  // VST_ENTRY: [valueid, namechar x N]
1682      if (ConvertToString(Record, 1, ValueName))
1683        return Error("Invalid record");
1684      unsigned ValueID = Record[0];
1685      if (ValueID >= ValueList.size())
1686        return Error("Invalid record");
1687      Value *V = ValueList[ValueID];
1688
1689      V->setName(StringRef(ValueName.data(), ValueName.size()));
1690      ValueName.clear();
1691      break;
1692    }
1693    case bitc::VST_CODE_BBENTRY: {
1694      if (ConvertToString(Record, 1, ValueName))
1695        return Error("Invalid record");
1696      BasicBlock *BB = getBasicBlock(Record[0]);
1697      if (!BB)
1698        return Error("Invalid record");
1699
1700      BB->setName(StringRef(ValueName.data(), ValueName.size()));
1701      ValueName.clear();
1702      break;
1703    }
1704    }
1705  }
1706}
1707
1708std::error_code BitcodeReader::ParseMetadata() {
1709  unsigned NextMDValueNo = MDValueList.size();
1710
1711  if (Stream.EnterSubBlock(bitc::METADATA_BLOCK_ID))
1712    return Error("Invalid record");
1713
1714  SmallVector<uint64_t, 64> Record;
1715
1716  // Read all the records.
1717  while (1) {
1718    unsigned Code = Stream.ReadCode();
1719    if (Code == bitc::END_BLOCK) {
1720      if (Stream.ReadBlockEnd())
1721        return Error("Malformed block");
1722      return std::error_code();
1723    }
1724
1725    if (Code == bitc::ENTER_SUBBLOCK) {
1726      // No known subblocks, always skip them.
1727      Stream.ReadSubBlockID();
1728      if (Stream.SkipBlock())
1729        return Error("Malformed block");
1730      continue;
1731    }
1732
1733    if (Code == bitc::DEFINE_ABBREV) {
1734      Stream.ReadAbbrevRecord();
1735      continue;
1736    }
1737
1738    bool IsFunctionLocal = false;
1739    // Read a record.
1740    Record.clear();
1741    Code = Stream.readRecord(Code, Record);
1742    switch (Code) {
1743    default:  // Default behavior: ignore.
1744      break;
1745    case bitc::METADATA_NAME: {
1746      // Read name of the named metadata.
1747      SmallString<8> Name(Record.begin(), Record.end());
1748      Record.clear();
1749      Code = Stream.ReadCode();
1750
1751      // METADATA_NAME is always followed by METADATA_NAMED_NODE.
1752      unsigned NextBitCode = Stream.readRecord(Code, Record);
1753      assert(NextBitCode == bitc::METADATA_NAMED_NODE); (void)NextBitCode;
1754
1755      // Read named metadata elements.
1756      unsigned Size = Record.size();
1757      NamedMDNode *NMD = TheModule->getOrInsertNamedMetadata(Name);
1758      for (unsigned i = 0; i != Size; ++i) {
1759        MDNode *MD = dyn_cast_or_null<MDNode>(MDValueList.getValueFwdRef(Record[i]));
1760        if (!MD)
1761          return Error("Invalid record");
1762        NMD->addOperand(MD);
1763      }
1764      break;
1765    }
1766    case bitc::METADATA_OLD_FN_NODE:
1767      IsFunctionLocal = true;
1768      // fall-through
1769    case bitc::METADATA_OLD_NODE: {
1770      if (Record.size() % 2 == 1)
1771        return Error("Invalid record");
1772
1773      unsigned Size = Record.size();
1774      SmallVector<Metadata *, 8> Elts;
1775      for (unsigned i = 0; i != Size; i += 2) {
1776        Type *Ty = getTypeByID(Record[i]);
1777        if (!Ty)
1778          return Error("Invalid record");
1779        if (Ty->isMetadataTy())
1780          Elts.push_back(MDValueList.getValueFwdRef(Record[i+1]));
1781        else if (!Ty->isVoidTy()) {
1782          auto *MD =
1783              ValueAsMetadata::get(ValueList.getValueFwdRef(Record[i + 1], Ty));
1784          assert(isa<ConstantAsMetadata>(MD) &&
1785                 "Expected non-function-local metadata");
1786          Elts.push_back(MD);
1787        } else
1788          Elts.push_back(nullptr);
1789      }
1790      MDValueList.AssignValue(MDNode::get(Context, Elts), NextMDValueNo++);
1791      break;
1792    }
1793    case bitc::METADATA_STRING: {
1794      std::string String(Record.begin(), Record.end());
1795      llvm::UpgradeMDStringConstant(String);
1796      Metadata *MD = MDString::get(Context, String);
1797      MDValueList.AssignValue(MD, NextMDValueNo++);
1798      break;
1799    }
1800    case bitc::METADATA_KIND: {
1801      if (Record.size() < 2)
1802        return Error("Invalid record");
1803
1804      unsigned Kind = Record[0];
1805      SmallString<8> Name(Record.begin()+1, Record.end());
1806
1807      unsigned NewKind = TheModule->getMDKindID(Name.str());
1808      if (!MDKindMap.insert(std::make_pair(Kind, NewKind)).second)
1809        return Error("Conflicting METADATA_KIND records");
1810      break;
1811    }
1812    }
1813  }
1814}
1815
1816/// decodeSignRotatedValue - Decode a signed value stored with the sign bit in
1817/// the LSB for dense VBR encoding.
1818uint64_t BitcodeReader::decodeSignRotatedValue(uint64_t V) {
1819  if ((V & 1) == 0)
1820    return V >> 1;
1821  if (V != 1)
1822    return -(V >> 1);
1823  // There is no such thing as -0 with integers.  "-0" really means MININT.
1824  return 1ULL << 63;
1825}
1826
1827// FIXME: Delete this in LLVM 4.0 and just assert that the aliasee is a
1828// GlobalObject.
1829static GlobalObject &
1830getGlobalObjectInExpr(const DenseMap<GlobalAlias *, Constant *> &Map,
1831                      Constant &C) {
1832  auto *GO = dyn_cast<GlobalObject>(&C);
1833  if (GO)
1834    return *GO;
1835
1836  auto *GA = dyn_cast<GlobalAlias>(&C);
1837  if (GA)
1838    return getGlobalObjectInExpr(Map, *Map.find(GA)->second);
1839
1840  auto &CE = cast<ConstantExpr>(C);
1841  assert(CE.getOpcode() == Instruction::BitCast ||
1842         CE.getOpcode() == Instruction::GetElementPtr ||
1843         CE.getOpcode() == Instruction::AddrSpaceCast);
1844  if (CE.getOpcode() == Instruction::GetElementPtr)
1845    assert(cast<GEPOperator>(CE).hasAllZeroIndices());
1846  return getGlobalObjectInExpr(Map, *CE.getOperand(0));
1847}
1848
1849/// ResolveGlobalAndAliasInits - Resolve all of the initializers for global
1850/// values and aliases that we can.
1851std::error_code BitcodeReader::ResolveGlobalAndAliasInits() {
1852  std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInitWorklist;
1853  std::vector<std::pair<GlobalAlias*, unsigned> > AliasInitWorklist;
1854
1855  GlobalInitWorklist.swap(GlobalInits);
1856  AliasInitWorklist.swap(AliasInits);
1857
1858  while (!GlobalInitWorklist.empty()) {
1859    unsigned ValID = GlobalInitWorklist.back().second;
1860    if (ValID >= ValueList.size()) {
1861      // Not ready to resolve this yet, it requires something later in the file.
1862      GlobalInits.push_back(GlobalInitWorklist.back());
1863    } else {
1864      if (Constant *C = dyn_cast_or_null<Constant>(ValueList[ValID]))
1865        GlobalInitWorklist.back().first->setInitializer(C);
1866      else
1867        return Error("Expected a constant");
1868    }
1869    GlobalInitWorklist.pop_back();
1870  }
1871
1872  // FIXME: Delete this in LLVM 4.0
1873  // Older versions of llvm could write an alias pointing to another. We cannot
1874  // construct those aliases, so we first collect an alias to aliasee expression
1875  // and then compute the actual aliasee.
1876  DenseMap<GlobalAlias *, Constant *> AliasInit;
1877
1878  while (!AliasInitWorklist.empty()) {
1879    unsigned ValID = AliasInitWorklist.back().second;
1880    if (ValID >= ValueList.size()) {
1881      AliasInits.push_back(AliasInitWorklist.back());
1882    } else {
1883      if (Constant *C = dyn_cast_or_null<Constant>(ValueList[ValID]))
1884        AliasInit.insert(std::make_pair(AliasInitWorklist.back().first, C));
1885      else
1886        return Error("Expected a constant");
1887    }
1888    AliasInitWorklist.pop_back();
1889  }
1890
1891  for (auto &Pair : AliasInit) {
1892    auto &GO = getGlobalObjectInExpr(AliasInit, *Pair.second);
1893    Pair.first->setAliasee(&GO);
1894  }
1895
1896  return std::error_code();
1897}
1898
1899static APInt ReadWideAPInt(ArrayRef<uint64_t> Vals, unsigned TypeBits) {
1900  SmallVector<uint64_t, 8> Words(Vals.size());
1901  std::transform(Vals.begin(), Vals.end(), Words.begin(),
1902                 BitcodeReader::decodeSignRotatedValue);
1903
1904  return APInt(TypeBits, Words);
1905}
1906
1907std::error_code BitcodeReader::ParseConstants() {
1908  if (Stream.EnterSubBlock(bitc::CONSTANTS_BLOCK_ID))
1909    return Error("Invalid record");
1910
1911  SmallVector<uint64_t, 64> Record;
1912
1913  // Read all the records for this value table.
1914  Type *CurTy = Type::getInt32Ty(Context);
1915  unsigned NextCstNo = ValueList.size();
1916  while (1) {
1917    BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
1918
1919    switch (Entry.Kind) {
1920    case BitstreamEntry::SubBlock: // Handled for us already.
1921    case BitstreamEntry::Error:
1922      return Error("Malformed block");
1923    case BitstreamEntry::EndBlock:
1924      if (NextCstNo != ValueList.size())
1925        return Error("Invalid constant reference");
1926
1927      // Once all the constants have been read, go through and resolve forward
1928      // references.
1929      ValueList.ResolveConstantForwardRefs();
1930      return std::error_code();
1931    case BitstreamEntry::Record:
1932      // The interesting case.
1933      break;
1934    }
1935
1936    // Read a record.
1937    Record.clear();
1938    Value *V = nullptr;
1939    unsigned BitCode = Stream.readRecord(Entry.ID, Record);
1940    switch (BitCode) {
1941    default:  // Default behavior: unknown constant
1942    case bitc::CST_CODE_UNDEF:     // UNDEF
1943      V = UndefValue::get(CurTy);
1944      break;
1945    case bitc::CST_CODE_SETTYPE:   // SETTYPE: [typeid]
1946      if (Record.empty())
1947        return Error("Invalid record");
1948      if (Record[0] >= TypeList.size())
1949        return Error("Invalid record");
1950      CurTy = TypeList[Record[0]];
1951      continue;  // Skip the ValueList manipulation.
1952    case bitc::CST_CODE_NULL:      // NULL
1953      V = Constant::getNullValue(CurTy);
1954      break;
1955    case bitc::CST_CODE_INTEGER:   // INTEGER: [intval]
1956      if (!CurTy->isIntegerTy() || Record.empty())
1957        return Error("Invalid record");
1958      V = ConstantInt::get(CurTy, decodeSignRotatedValue(Record[0]));
1959      break;
1960    case bitc::CST_CODE_WIDE_INTEGER: {// WIDE_INTEGER: [n x intval]
1961      if (!CurTy->isIntegerTy() || Record.empty())
1962        return Error("Invalid record");
1963
1964      APInt VInt = ReadWideAPInt(Record,
1965                                 cast<IntegerType>(CurTy)->getBitWidth());
1966      V = ConstantInt::get(Context, VInt);
1967
1968      break;
1969    }
1970    case bitc::CST_CODE_FLOAT: {    // FLOAT: [fpval]
1971      if (Record.empty())
1972        return Error("Invalid record");
1973      if (CurTy->isHalfTy())
1974        V = ConstantFP::get(Context, APFloat(APFloat::IEEEhalf,
1975                                             APInt(16, (uint16_t)Record[0])));
1976      else if (CurTy->isFloatTy())
1977        V = ConstantFP::get(Context, APFloat(APFloat::IEEEsingle,
1978                                             APInt(32, (uint32_t)Record[0])));
1979      else if (CurTy->isDoubleTy())
1980        V = ConstantFP::get(Context, APFloat(APFloat::IEEEdouble,
1981                                             APInt(64, Record[0])));
1982      else if (CurTy->isX86_FP80Ty()) {
1983        // Bits are not stored the same way as a normal i80 APInt, compensate.
1984        uint64_t Rearrange[2];
1985        Rearrange[0] = (Record[1] & 0xffffLL) | (Record[0] << 16);
1986        Rearrange[1] = Record[0] >> 48;
1987        V = ConstantFP::get(Context, APFloat(APFloat::x87DoubleExtended,
1988                                             APInt(80, Rearrange)));
1989      } else if (CurTy->isFP128Ty())
1990        V = ConstantFP::get(Context, APFloat(APFloat::IEEEquad,
1991                                             APInt(128, Record)));
1992      else if (CurTy->isPPC_FP128Ty())
1993        V = ConstantFP::get(Context, APFloat(APFloat::PPCDoubleDouble,
1994                                             APInt(128, Record)));
1995      else
1996        V = UndefValue::get(CurTy);
1997      break;
1998    }
1999
2000    case bitc::CST_CODE_AGGREGATE: {// AGGREGATE: [n x value number]
2001      if (Record.empty())
2002        return Error("Invalid record");
2003
2004      unsigned Size = Record.size();
2005      SmallVector<Constant*, 16> Elts;
2006
2007      if (StructType *STy = dyn_cast<StructType>(CurTy)) {
2008        for (unsigned i = 0; i != Size; ++i)
2009          Elts.push_back(ValueList.getConstantFwdRef(Record[i],
2010                                                     STy->getElementType(i)));
2011        V = ConstantStruct::get(STy, Elts);
2012      } else if (ArrayType *ATy = dyn_cast<ArrayType>(CurTy)) {
2013        Type *EltTy = ATy->getElementType();
2014        for (unsigned i = 0; i != Size; ++i)
2015          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
2016        V = ConstantArray::get(ATy, Elts);
2017      } else if (VectorType *VTy = dyn_cast<VectorType>(CurTy)) {
2018        Type *EltTy = VTy->getElementType();
2019        for (unsigned i = 0; i != Size; ++i)
2020          Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
2021        V = ConstantVector::get(Elts);
2022      } else {
2023        V = UndefValue::get(CurTy);
2024      }
2025      break;
2026    }
2027    case bitc::CST_CODE_STRING: { // STRING: [values]
2028      if (Record.empty())
2029        return Error("Invalid record");
2030
2031      ArrayType *ATy = cast<ArrayType>(CurTy);
2032      Type *EltTy = ATy->getElementType();
2033
2034      unsigned Size = Record.size();
2035      std::vector<Constant*> Elts;
2036      for (unsigned i = 0; i != Size; ++i)
2037        Elts.push_back(ConstantInt::get(EltTy, Record[i]));
2038      V = ConstantArray::get(ATy, Elts);
2039      break;
2040    }
2041    case bitc::CST_CODE_CSTRING: { // CSTRING: [values]
2042      if (Record.empty())
2043        return Error("Invalid record");
2044
2045      ArrayType *ATy = cast<ArrayType>(CurTy);
2046      Type *EltTy = ATy->getElementType();
2047
2048      unsigned Size = Record.size();
2049      std::vector<Constant*> Elts;
2050      for (unsigned i = 0; i != Size; ++i)
2051        Elts.push_back(ConstantInt::get(EltTy, Record[i]));
2052      Elts.push_back(Constant::getNullValue(EltTy));
2053      V = ConstantArray::get(ATy, Elts);
2054      break;
2055    }
2056    case bitc::CST_CODE_CE_BINOP: {  // CE_BINOP: [opcode, opval, opval]
2057      if (Record.size() < 3)
2058        return Error("Invalid record");
2059      int Opc = GetDecodedBinaryOpcode(Record[0], CurTy);
2060      if (Opc < 0) {
2061        V = UndefValue::get(CurTy);  // Unknown binop.
2062      } else {
2063        Constant *LHS = ValueList.getConstantFwdRef(Record[1], CurTy);
2064        Constant *RHS = ValueList.getConstantFwdRef(Record[2], CurTy);
2065        unsigned Flags = 0;
2066        if (Record.size() >= 4) {
2067          if (Opc == Instruction::Add ||
2068              Opc == Instruction::Sub ||
2069              Opc == Instruction::Mul ||
2070              Opc == Instruction::Shl) {
2071            if (Record[3] & (1 << bitc::OBO_NO_SIGNED_WRAP))
2072              Flags |= OverflowingBinaryOperator::NoSignedWrap;
2073            if (Record[3] & (1 << bitc::OBO_NO_UNSIGNED_WRAP))
2074              Flags |= OverflowingBinaryOperator::NoUnsignedWrap;
2075          } else if (Opc == Instruction::SDiv ||
2076                     Opc == Instruction::UDiv ||
2077                     Opc == Instruction::LShr ||
2078                     Opc == Instruction::AShr) {
2079            if (Record[3] & (1 << bitc::PEO_EXACT))
2080              Flags |= SDivOperator::IsExact;
2081          }
2082        }
2083        V = ConstantExpr::get(Opc, LHS, RHS, Flags);
2084      }
2085      break;
2086    }
2087    case bitc::CST_CODE_CE_CAST: {  // CE_CAST: [opcode, opty, opval]
2088      if (Record.size() < 3)
2089        return Error("Invalid record");
2090      int Opc = GetDecodedCastOpcode(Record[0]);
2091      if (Opc < 0) {
2092        V = UndefValue::get(CurTy);  // Unknown cast.
2093      } else {
2094        Type *OpTy = getTypeByID(Record[1]);
2095        if (!OpTy)
2096          return Error("Invalid record");
2097        Constant *Op = ValueList.getConstantFwdRef(Record[2], OpTy);
2098        V = ConstantExpr::getCast(Opc, Op, CurTy);
2099      }
2100      break;
2101    }
2102    case bitc::CST_CODE_CE_INBOUNDS_GEP:
2103    case bitc::CST_CODE_CE_GEP: {  // CE_GEP:        [n x operands]
2104      Type *PointeeType = nullptr;
2105      if (Record.size() & 1)
2106        return Error("Invalid record");
2107      SmallVector<Constant*, 16> Elts;
2108      for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
2109        Type *ElTy = getTypeByID(Record[i]);
2110        if (!ElTy)
2111          return Error("Invalid record");
2112        Elts.push_back(ValueList.getConstantFwdRef(Record[i+1], ElTy));
2113      }
2114      ArrayRef<Constant *> Indices(Elts.begin() + 1, Elts.end());
2115      V = ConstantExpr::getGetElementPtr(PointeeType, Elts[0], Indices,
2116                                         BitCode ==
2117                                           bitc::CST_CODE_CE_INBOUNDS_GEP);
2118      break;
2119    }
2120    case bitc::CST_CODE_CE_SELECT:  // CE_SELECT: [opval#, opval#, opval#]
2121      if (Record.size() < 3)
2122        return Error("Invalid record");
2123      V = ConstantExpr::getSelect(ValueList.getConstantFwdRef(Record[0],
2124                                                              Type::getInt1Ty(Context)),
2125                                  ValueList.getConstantFwdRef(Record[1],CurTy),
2126                                  ValueList.getConstantFwdRef(Record[2],CurTy));
2127      break;
2128    case bitc::CST_CODE_CE_EXTRACTELT: { // CE_EXTRACTELT: [opty, opval, opval]
2129      if (Record.size() < 3)
2130        return Error("Invalid record");
2131      VectorType *OpTy =
2132        dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
2133      if (!OpTy)
2134        return Error("Invalid record");
2135      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
2136      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], Type::getInt32Ty(Context));
2137      V = ConstantExpr::getExtractElement(Op0, Op1);
2138      break;
2139    }
2140    case bitc::CST_CODE_CE_INSERTELT: { // CE_INSERTELT: [opval, opval, opval]
2141      VectorType *OpTy = dyn_cast<VectorType>(CurTy);
2142      if (Record.size() < 3 || !OpTy)
2143        return Error("Invalid record");
2144      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
2145      Constant *Op1 = ValueList.getConstantFwdRef(Record[1],
2146                                                  OpTy->getElementType());
2147      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], Type::getInt32Ty(Context));
2148      V = ConstantExpr::getInsertElement(Op0, Op1, Op2);
2149      break;
2150    }
2151    case bitc::CST_CODE_CE_SHUFFLEVEC: { // CE_SHUFFLEVEC: [opval, opval, opval]
2152      VectorType *OpTy = dyn_cast<VectorType>(CurTy);
2153      if (Record.size() < 3 || !OpTy)
2154        return Error("Invalid record");
2155      Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
2156      Constant *Op1 = ValueList.getConstantFwdRef(Record[1], OpTy);
2157      Type *ShufTy = VectorType::get(Type::getInt32Ty(Context),
2158                                                 OpTy->getNumElements());
2159      Constant *Op2 = ValueList.getConstantFwdRef(Record[2], ShufTy);
2160      V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
2161      break;
2162    }
2163    case bitc::CST_CODE_CE_SHUFVEC_EX: { // [opty, opval, opval, opval]
2164      VectorType *RTy = dyn_cast<VectorType>(CurTy);
2165      VectorType *OpTy =
2166        dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
2167      if (Record.size() < 4 || !RTy || !OpTy)
2168        return Error("Invalid record");
2169      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
2170      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
2171      Type *ShufTy = VectorType::get(Type::getInt32Ty(Context),
2172                                                 RTy->getNumElements());
2173      Constant *Op2 = ValueList.getConstantFwdRef(Record[3], ShufTy);
2174      V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
2175      break;
2176    }
2177    case bitc::CST_CODE_CE_CMP: {     // CE_CMP: [opty, opval, opval, pred]
2178      if (Record.size() < 4)
2179        return Error("Invalid record");
2180      Type *OpTy = getTypeByID(Record[0]);
2181      if (!OpTy)
2182        return Error("Invalid record");
2183      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
2184      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
2185
2186      if (OpTy->isFPOrFPVectorTy())
2187        V = ConstantExpr::getFCmp(Record[3], Op0, Op1);
2188      else
2189        V = ConstantExpr::getICmp(Record[3], Op0, Op1);
2190      break;
2191    }
2192    case bitc::CST_CODE_INLINEASM:
2193    case bitc::CST_CODE_INLINEASM_OLD: {
2194      if (Record.size() < 2)
2195        return Error("Invalid record");
2196      std::string AsmStr, ConstrStr;
2197      bool HasSideEffects = Record[0] & 1;
2198      bool IsAlignStack = Record[0] >> 1;
2199      unsigned AsmStrSize = Record[1];
2200      if (2+AsmStrSize >= Record.size())
2201        return Error("Invalid record");
2202      unsigned ConstStrSize = Record[2+AsmStrSize];
2203      if (3+AsmStrSize+ConstStrSize > Record.size())
2204        return Error("Invalid record");
2205
2206      for (unsigned i = 0; i != AsmStrSize; ++i)
2207        AsmStr += (char)Record[2+i];
2208      for (unsigned i = 0; i != ConstStrSize; ++i)
2209        ConstrStr += (char)Record[3+AsmStrSize+i];
2210      PointerType *PTy = cast<PointerType>(CurTy);
2211      V = InlineAsm::get(cast<FunctionType>(PTy->getElementType()),
2212                         AsmStr, ConstrStr, HasSideEffects, IsAlignStack);
2213      break;
2214    }
2215    case bitc::CST_CODE_BLOCKADDRESS:{
2216      if (Record.size() < 3)
2217        return Error("Invalid record");
2218      Type *FnTy = getTypeByID(Record[0]);
2219      if (!FnTy)
2220        return Error("Invalid record");
2221      Function *Fn =
2222        dyn_cast_or_null<Function>(ValueList.getConstantFwdRef(Record[1],FnTy));
2223      if (!Fn)
2224        return Error("Invalid record");
2225
2226      GlobalVariable *FwdRef = new GlobalVariable(*Fn->getParent(),
2227                                                  Type::getInt8Ty(Context),
2228                                            false, GlobalValue::InternalLinkage,
2229                                                  0, "");
2230      BlockAddrFwdRefs[Fn].push_back(std::make_pair(Record[2], FwdRef));
2231      V = FwdRef;
2232      break;
2233    }
2234    }
2235
2236    ValueList.AssignValue(V, NextCstNo);
2237    ++NextCstNo;
2238  }
2239
2240  if (NextCstNo != ValueList.size())
2241    return Error("Invalid constant reference");
2242
2243  if (Stream.ReadBlockEnd())
2244    return Error("Expected a constant");
2245
2246  // Once all the constants have been read, go through and resolve forward
2247  // references.
2248  ValueList.ResolveConstantForwardRefs();
2249  return std::error_code();
2250}
2251
2252std::error_code BitcodeReader::materializeMetadata() {
2253  return std::error_code();
2254}
2255
2256void BitcodeReader::setStripDebugInfo() { }
2257
2258/// RememberAndSkipFunctionBody - When we see the block for a function body,
2259/// remember where it is and then skip it.  This lets us lazily deserialize the
2260/// functions.
2261std::error_code BitcodeReader::RememberAndSkipFunctionBody() {
2262  // Get the function we are talking about.
2263  if (FunctionsWithBodies.empty())
2264    return Error("Insufficient function protos");
2265
2266  Function *Fn = FunctionsWithBodies.back();
2267  FunctionsWithBodies.pop_back();
2268
2269  // Save the current stream state.
2270  uint64_t CurBit = Stream.GetCurrentBitNo();
2271  DeferredFunctionInfo[Fn] = CurBit;
2272
2273  // Skip over the function block for now.
2274  if (Stream.SkipBlock())
2275    return Error("Invalid record");
2276  return std::error_code();
2277}
2278
2279std::error_code BitcodeReader::GlobalCleanup() {
2280  // Patch the initializers for globals and aliases up.
2281  ResolveGlobalAndAliasInits();
2282  if (!GlobalInits.empty() || !AliasInits.empty())
2283    return Error("Malformed global initializer set");
2284
2285  // Look for intrinsic functions which need to be upgraded at some point
2286  for (Module::iterator FI = TheModule->begin(), FE = TheModule->end();
2287       FI != FE; ++FI) {
2288    Function *NewFn;
2289    if (UpgradeIntrinsicFunction(FI, NewFn))
2290      UpgradedIntrinsics.push_back(std::make_pair(FI, NewFn));
2291  }
2292
2293  // Look for global variables which need to be renamed.
2294  for (Module::global_iterator
2295         GI = TheModule->global_begin(), GE = TheModule->global_end();
2296       GI != GE;) {
2297    GlobalVariable *GV = GI++;
2298    UpgradeGlobalVariable(GV);
2299  }
2300
2301  // Force deallocation of memory for these vectors to favor the client that
2302  // want lazy deserialization.
2303  std::vector<std::pair<GlobalVariable*, unsigned> >().swap(GlobalInits);
2304  std::vector<std::pair<GlobalAlias*, unsigned> >().swap(AliasInits);
2305  return std::error_code();
2306}
2307
2308std::error_code BitcodeReader::ParseModule(bool Resume) {
2309  if (Resume)
2310    Stream.JumpToBit(NextUnreadBit);
2311  else if (Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
2312    return Error("Invalid record");
2313
2314  SmallVector<uint64_t, 64> Record;
2315  std::vector<std::string> SectionTable;
2316  std::vector<std::string> GCTable;
2317
2318  // Read all the records for this module.
2319  while (1) {
2320    BitstreamEntry Entry = Stream.advance();
2321
2322    switch (Entry.Kind) {
2323    case BitstreamEntry::Error:
2324      return Error("Malformed block");
2325    case BitstreamEntry::EndBlock:
2326      return GlobalCleanup();
2327
2328    case BitstreamEntry::SubBlock:
2329      switch (Entry.ID) {
2330      default:  // Skip unknown content.
2331        if (Stream.SkipBlock())
2332          return Error("Invalid record");
2333        break;
2334      case bitc::BLOCKINFO_BLOCK_ID:
2335        if (Stream.ReadBlockInfoBlock())
2336          return Error("Malformed block");
2337        break;
2338      case bitc::PARAMATTR_BLOCK_ID:
2339        if (std::error_code EC = ParseAttributeBlock())
2340          return EC;
2341        break;
2342      case bitc::TYPE_BLOCK_ID_NEW:
2343        if (std::error_code EC = ParseTypeTable())
2344          return EC;
2345        break;
2346      case TYPE_BLOCK_ID_OLD_3_0:
2347        if (std::error_code EC = ParseOldTypeTable())
2348          return EC;
2349        break;
2350      case TYPE_SYMTAB_BLOCK_ID_OLD_3_0:
2351        if (std::error_code EC = ParseOldTypeSymbolTable())
2352          return EC;
2353        break;
2354      case bitc::VALUE_SYMTAB_BLOCK_ID:
2355        if (std::error_code EC = ParseValueSymbolTable())
2356          return EC;
2357        SeenValueSymbolTable = true;
2358        break;
2359      case bitc::CONSTANTS_BLOCK_ID:
2360        if (std::error_code EC = ParseConstants())
2361          return EC;
2362        if (std::error_code EC = ResolveGlobalAndAliasInits())
2363          return EC;
2364        break;
2365      case bitc::METADATA_BLOCK_ID:
2366        if (std::error_code EC = ParseMetadata())
2367          return EC;
2368        break;
2369      case bitc::FUNCTION_BLOCK_ID:
2370        // If this is the first function body we've seen, reverse the
2371        // FunctionsWithBodies list.
2372        if (!SeenFirstFunctionBody) {
2373          std::reverse(FunctionsWithBodies.begin(), FunctionsWithBodies.end());
2374          if (std::error_code EC = GlobalCleanup())
2375            return EC;
2376          SeenFirstFunctionBody = true;
2377        }
2378
2379        if (std::error_code EC = RememberAndSkipFunctionBody())
2380          return EC;
2381        // For streaming bitcode, suspend parsing when we reach the function
2382        // bodies. Subsequent materialization calls will resume it when
2383        // necessary. For streaming, the function bodies must be at the end of
2384        // the bitcode. If the bitcode file is old, the symbol table will be
2385        // at the end instead and will not have been seen yet. In this case,
2386        // just finish the parse now.
2387        if (LazyStreamer && SeenValueSymbolTable) {
2388          NextUnreadBit = Stream.GetCurrentBitNo();
2389          return std::error_code();
2390        }
2391        break;
2392        break;
2393      }
2394      continue;
2395
2396    case BitstreamEntry::Record:
2397      // The interesting case.
2398      break;
2399    }
2400
2401
2402    // Read a record.
2403    switch (Stream.readRecord(Entry.ID, Record)) {
2404    default: break;  // Default behavior, ignore unknown content.
2405    case bitc::MODULE_CODE_VERSION: {  // VERSION: [version#]
2406      if (Record.size() < 1)
2407        return Error("Invalid record");
2408      // Only version #0 is supported so far.
2409      if (Record[0] != 0)
2410        return Error("Invalid value");
2411      break;
2412    }
2413    case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
2414      std::string S;
2415      if (ConvertToString(Record, 0, S))
2416        return Error("Invalid record");
2417      TheModule->setTargetTriple(S);
2418      break;
2419    }
2420    case bitc::MODULE_CODE_DATALAYOUT: {  // DATALAYOUT: [strchr x N]
2421      std::string S;
2422      if (ConvertToString(Record, 0, S))
2423        return Error("Invalid record");
2424      TheModule->setDataLayout(S);
2425      break;
2426    }
2427    case bitc::MODULE_CODE_ASM: {  // ASM: [strchr x N]
2428      std::string S;
2429      if (ConvertToString(Record, 0, S))
2430        return Error("Invalid record");
2431      TheModule->setModuleInlineAsm(S);
2432      break;
2433    }
2434    case bitc::MODULE_CODE_DEPLIB: {  // DEPLIB: [strchr x N]
2435      std::string S;
2436      if (ConvertToString(Record, 0, S))
2437        return Error("Invalid record");
2438      // ANDROID: Ignore value, since we never used it anyways.
2439      // TheModule->addLibrary(S);
2440      break;
2441    }
2442    case bitc::MODULE_CODE_SECTIONNAME: {  // SECTIONNAME: [strchr x N]
2443      std::string S;
2444      if (ConvertToString(Record, 0, S))
2445        return Error("Invalid record");
2446      SectionTable.push_back(S);
2447      break;
2448    }
2449    case bitc::MODULE_CODE_GCNAME: {  // SECTIONNAME: [strchr x N]
2450      std::string S;
2451      if (ConvertToString(Record, 0, S))
2452        return Error("Invalid record");
2453      GCTable.push_back(S);
2454      break;
2455    }
2456    // GLOBALVAR: [pointer type, isconst, initid,
2457    //             linkage, alignment, section, visibility, threadlocal,
2458    //             unnamed_addr]
2459    case bitc::MODULE_CODE_GLOBALVAR: {
2460      if (Record.size() < 6)
2461        return Error("Invalid record");
2462      Type *Ty = getTypeByID(Record[0]);
2463      if (!Ty)
2464        return Error("Invalid record");
2465      if (!Ty->isPointerTy())
2466        return Error("Invalid type for value");
2467      unsigned AddressSpace = cast<PointerType>(Ty)->getAddressSpace();
2468      Ty = cast<PointerType>(Ty)->getElementType();
2469
2470      bool isConstant = Record[1];
2471      uint64_t RawLinkage = Record[3];
2472      GlobalValue::LinkageTypes Linkage = getDecodedLinkage(RawLinkage);
2473      unsigned Alignment = (1 << Record[4]) >> 1;
2474      std::string Section;
2475      if (Record[5]) {
2476        if (Record[5]-1 >= SectionTable.size())
2477          return Error("Invalid ID");
2478        Section = SectionTable[Record[5]-1];
2479      }
2480      GlobalValue::VisibilityTypes Visibility = GlobalValue::DefaultVisibility;
2481      if (Record.size() > 6)
2482        Visibility = GetDecodedVisibility(Record[6]);
2483
2484      GlobalVariable::ThreadLocalMode TLM = GlobalVariable::NotThreadLocal;
2485      if (Record.size() > 7)
2486        TLM = GetDecodedThreadLocalMode(Record[7]);
2487
2488      bool UnnamedAddr = false;
2489      if (Record.size() > 8)
2490        UnnamedAddr = Record[8];
2491
2492      GlobalVariable *NewGV =
2493        new GlobalVariable(*TheModule, Ty, isConstant, Linkage, nullptr, "", nullptr,
2494                           TLM, AddressSpace);
2495      NewGV->setAlignment(Alignment);
2496      if (!Section.empty())
2497        NewGV->setSection(Section);
2498      NewGV->setVisibility(Visibility);
2499      NewGV->setUnnamedAddr(UnnamedAddr);
2500
2501      ValueList.push_back(NewGV);
2502
2503      // Remember which value to use for the global initializer.
2504      if (unsigned InitID = Record[2])
2505        GlobalInits.push_back(std::make_pair(NewGV, InitID-1));
2506      break;
2507    }
2508    // FUNCTION:  [type, callingconv, isproto, linkage, paramattr,
2509    //             alignment, section, visibility, gc, unnamed_addr]
2510    case bitc::MODULE_CODE_FUNCTION: {
2511      if (Record.size() < 8)
2512        return Error("Invalid record");
2513      Type *Ty = getTypeByID(Record[0]);
2514      if (!Ty)
2515        return Error("Invalid record");
2516      if (!Ty->isPointerTy())
2517        return Error("Invalid type for value");
2518      FunctionType *FTy =
2519        dyn_cast<FunctionType>(cast<PointerType>(Ty)->getElementType());
2520      if (!FTy)
2521        return Error("Invalid type for value");
2522
2523      Function *Func = Function::Create(FTy, GlobalValue::ExternalLinkage,
2524                                        "", TheModule);
2525
2526      Func->setCallingConv(static_cast<CallingConv::ID>(Record[1]));
2527      bool isProto = Record[2];
2528      uint64_t RawLinkage = Record[3];
2529      Func->setLinkage(getDecodedLinkage(RawLinkage));
2530      Func->setAttributes(getAttributes(Record[4]));
2531
2532      Func->setAlignment((1 << Record[5]) >> 1);
2533      if (Record[6]) {
2534        if (Record[6]-1 >= SectionTable.size())
2535          return Error("Invalid ID");
2536        Func->setSection(SectionTable[Record[6]-1]);
2537      }
2538      Func->setVisibility(GetDecodedVisibility(Record[7]));
2539      if (Record.size() > 8 && Record[8]) {
2540        if (Record[8]-1 > GCTable.size())
2541          return Error("Invalid ID");
2542        Func->setGC(GCTable[Record[8]-1].c_str());
2543      }
2544      bool UnnamedAddr = false;
2545      if (Record.size() > 9)
2546        UnnamedAddr = Record[9];
2547      Func->setUnnamedAddr(UnnamedAddr);
2548      ValueList.push_back(Func);
2549
2550      // If this is a function with a body, remember the prototype we are
2551      // creating now, so that we can match up the body with them later.
2552      if (!isProto) {
2553        Func->setIsMaterializable(true);
2554        FunctionsWithBodies.push_back(Func);
2555        if (LazyStreamer)
2556          DeferredFunctionInfo[Func] = 0;
2557      }
2558      break;
2559    }
2560    // ALIAS: [alias type, aliasee val#, linkage]
2561    // ALIAS: [alias type, aliasee val#, linkage, visibility]
2562    case bitc::MODULE_CODE_ALIAS: {
2563      if (Record.size() < 3)
2564        return Error("Invalid record");
2565      Type *Ty = getTypeByID(Record[0]);
2566      if (!Ty)
2567        return Error("Invalid record");
2568      auto *PTy = dyn_cast<PointerType>(Ty);
2569      if (!PTy)
2570        return Error("Invalid type for value");
2571
2572      auto *NewGA =
2573          GlobalAlias::create(PTy->getElementType(), PTy->getAddressSpace(),
2574                              getDecodedLinkage(Record[2]), "", TheModule);
2575      // Old bitcode files didn't have visibility field.
2576      if (Record.size() > 3)
2577        NewGA->setVisibility(GetDecodedVisibility(Record[3]));
2578      ValueList.push_back(NewGA);
2579      AliasInits.push_back(std::make_pair(NewGA, Record[1]));
2580      break;
2581    }
2582    /// MODULE_CODE_PURGEVALS: [numvals]
2583    case bitc::MODULE_CODE_PURGEVALS:
2584      // Trim down the value list to the specified size.
2585      if (Record.size() < 1 || Record[0] > ValueList.size())
2586        return Error("Invalid record");
2587      ValueList.shrinkTo(Record[0]);
2588      break;
2589    }
2590    Record.clear();
2591  }
2592}
2593
2594std::error_code BitcodeReader::ParseBitcodeInto(Module *M) {
2595  TheModule = nullptr;
2596
2597  if (std::error_code EC = InitStream())
2598    return EC;
2599
2600  // Sniff for the signature.
2601  if (Stream.Read(8) != 'B' ||
2602      Stream.Read(8) != 'C' ||
2603      Stream.Read(4) != 0x0 ||
2604      Stream.Read(4) != 0xC ||
2605      Stream.Read(4) != 0xE ||
2606      Stream.Read(4) != 0xD)
2607    return Error("Invalid bitcode signature");
2608
2609  // We expect a number of well-defined blocks, though we don't necessarily
2610  // need to understand them all.
2611  while (1) {
2612    if (Stream.AtEndOfStream())
2613      return std::error_code();
2614
2615    BitstreamEntry Entry =
2616      Stream.advance(BitstreamCursor::AF_DontAutoprocessAbbrevs);
2617
2618    switch (Entry.Kind) {
2619    case BitstreamEntry::Error:
2620      return Error("Malformed block");
2621    case BitstreamEntry::EndBlock:
2622      return std::error_code();
2623
2624    case BitstreamEntry::SubBlock:
2625      switch (Entry.ID) {
2626      case bitc::BLOCKINFO_BLOCK_ID:
2627        if (Stream.ReadBlockInfoBlock())
2628          return Error("Malformed block");
2629        break;
2630      case bitc::MODULE_BLOCK_ID:
2631        // Reject multiple MODULE_BLOCK's in a single bitstream.
2632        if (TheModule)
2633          return Error("Invalid multiple blocks");
2634        TheModule = M;
2635        if (std::error_code EC = ParseModule(false))
2636          return EC;
2637        if (LazyStreamer)
2638          return std::error_code();
2639        break;
2640      default:
2641        if (Stream.SkipBlock())
2642          return Error("Invalid record");
2643        break;
2644      }
2645      continue;
2646    case BitstreamEntry::Record:
2647      // There should be no records in the top-level of blocks.
2648
2649      // The ranlib in Xcode 4 will align archive members by appending newlines
2650      // to the end of them. If this file size is a multiple of 4 but not 8, we
2651      // have to read and ignore these final 4 bytes :-(
2652      if (Stream.getAbbrevIDWidth() == 2 && Entry.ID == 2 &&
2653          Stream.Read(6) == 2 && Stream.Read(24) == 0xa0a0a &&
2654          Stream.AtEndOfStream())
2655        return std::error_code();
2656
2657      return Error("Invalid record");
2658    }
2659  }
2660}
2661
2662llvm::ErrorOr<std::string> BitcodeReader::parseModuleTriple() {
2663  if (Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
2664    return Error("Invalid record");
2665
2666  SmallVector<uint64_t, 64> Record;
2667
2668  std::string Triple;
2669  // Read all the records for this module.
2670  while (1) {
2671    BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
2672
2673    switch (Entry.Kind) {
2674    case BitstreamEntry::SubBlock: // Handled for us already.
2675    case BitstreamEntry::Error:
2676      return Error("Malformed block");
2677    case BitstreamEntry::EndBlock:
2678      return Triple;
2679    case BitstreamEntry::Record:
2680      // The interesting case.
2681      break;
2682    }
2683
2684    // Read a record.
2685    switch (Stream.readRecord(Entry.ID, Record)) {
2686    default: break;  // Default behavior, ignore unknown content.
2687    case bitc::MODULE_CODE_VERSION:  // VERSION: [version#]
2688      if (Record.size() < 1)
2689        return Error("Invalid record");
2690      // Only version #0 is supported so far.
2691      if (Record[0] != 0)
2692        return Error("Invalid record");
2693      break;
2694    case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
2695      std::string S;
2696      if (ConvertToString(Record, 0, S))
2697        return Error("Invalid record");
2698      Triple = S;
2699      break;
2700    }
2701    }
2702    Record.clear();
2703  }
2704
2705  return Error("Invalid bitcode signature");
2706}
2707
2708llvm::ErrorOr<std::string> BitcodeReader::parseTriple() {
2709  if (std::error_code EC = InitStream())
2710    return EC;
2711
2712  // Sniff for the signature.
2713  if (Stream.Read(8) != 'B' ||
2714      Stream.Read(8) != 'C' ||
2715      Stream.Read(4) != 0x0 ||
2716      Stream.Read(4) != 0xC ||
2717      Stream.Read(4) != 0xE ||
2718      Stream.Read(4) != 0xD)
2719    return Error("Invalid bitcode signature");
2720
2721  // We expect a number of well-defined blocks, though we don't necessarily
2722  // need to understand them all.
2723  while (1) {
2724    BitstreamEntry Entry = Stream.advance();
2725
2726    switch (Entry.Kind) {
2727    case BitstreamEntry::Error:
2728      return Error("Malformed block");
2729    case BitstreamEntry::EndBlock:
2730      return std::error_code();
2731
2732    case BitstreamEntry::SubBlock:
2733      if (Entry.ID == bitc::MODULE_BLOCK_ID)
2734        return parseModuleTriple();
2735
2736      // Ignore other sub-blocks.
2737      if (Stream.SkipBlock())
2738        return Error("Malformed block");
2739      continue;
2740
2741    case BitstreamEntry::Record:
2742      Stream.skipRecord(Entry.ID);
2743      continue;
2744    }
2745  }
2746}
2747
2748/// ParseMetadataAttachment - Parse metadata attachments.
2749std::error_code BitcodeReader::ParseMetadataAttachment() {
2750  if (Stream.EnterSubBlock(bitc::METADATA_ATTACHMENT_ID))
2751    return Error("Invalid record");
2752
2753  SmallVector<uint64_t, 64> Record;
2754  while (1) {
2755    BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
2756
2757    switch (Entry.Kind) {
2758    case BitstreamEntry::SubBlock: // Handled for us already.
2759    case BitstreamEntry::Error:
2760      return Error("Malformed block");
2761    case BitstreamEntry::EndBlock:
2762      return std::error_code();
2763    case BitstreamEntry::Record:
2764      // The interesting case.
2765      break;
2766    }
2767
2768    // Read a metadata attachment record.
2769    Record.clear();
2770    switch (Stream.readRecord(Entry.ID, Record)) {
2771    default:  // Default behavior: ignore.
2772      break;
2773    case bitc::METADATA_ATTACHMENT: {
2774      unsigned RecordLength = Record.size();
2775      if (Record.empty() || (RecordLength - 1) % 2 == 1)
2776        return Error("Invalid record");
2777      Instruction *Inst = InstructionList[Record[0]];
2778      for (unsigned i = 1; i != RecordLength; i = i+2) {
2779        unsigned Kind = Record[i];
2780        DenseMap<unsigned, unsigned>::iterator I =
2781          MDKindMap.find(Kind);
2782        if (I == MDKindMap.end())
2783          return Error("Invalid ID");
2784        Metadata *Node = MDValueList.getValueFwdRef(Record[i + 1]);
2785        Inst->setMetadata(I->second, cast<MDNode>(Node));
2786      }
2787      break;
2788    }
2789    }
2790  }
2791}
2792
2793/// ParseFunctionBody - Lazily parse the specified function body block.
2794std::error_code BitcodeReader::ParseFunctionBody(Function *F) {
2795  if (Stream.EnterSubBlock(bitc::FUNCTION_BLOCK_ID))
2796    return Error("Invalid record");
2797
2798  InstructionList.clear();
2799  unsigned ModuleValueListSize = ValueList.size();
2800  unsigned ModuleMDValueListSize = MDValueList.size();
2801
2802  // Add all the function arguments to the value table.
2803  for(Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
2804    ValueList.push_back(I);
2805
2806  unsigned NextValueNo = ValueList.size();
2807  BasicBlock *CurBB = nullptr;
2808  unsigned CurBBNo = 0;
2809
2810  DebugLoc LastLoc;
2811
2812  // Read all the records.
2813  SmallVector<uint64_t, 64> Record;
2814  while (1) {
2815    unsigned Code = Stream.ReadCode();
2816    if (Code == bitc::END_BLOCK) {
2817      if (Stream.ReadBlockEnd())
2818        return Error("Malformed block");
2819      break;
2820    }
2821
2822    if (Code == bitc::ENTER_SUBBLOCK) {
2823      switch (Stream.ReadSubBlockID()) {
2824      default:  // Skip unknown content.
2825        if (Stream.SkipBlock())
2826          return Error("Invalid record");
2827        break;
2828      case bitc::CONSTANTS_BLOCK_ID:
2829        if (std::error_code EC = ParseConstants())
2830          return EC;
2831        NextValueNo = ValueList.size();
2832        break;
2833      case bitc::VALUE_SYMTAB_BLOCK_ID:
2834        if (std::error_code EC = ParseValueSymbolTable())
2835          return EC;
2836        break;
2837      case bitc::METADATA_ATTACHMENT_ID:
2838        if (std::error_code EC = ParseMetadataAttachment())
2839          return EC;
2840        break;
2841      case bitc::METADATA_BLOCK_ID:
2842        if (std::error_code EC = ParseMetadata())
2843          return EC;
2844        break;
2845      }
2846      continue;
2847    }
2848
2849    if (Code == bitc::DEFINE_ABBREV) {
2850      Stream.ReadAbbrevRecord();
2851      continue;
2852    }
2853
2854    // Read a record.
2855    Record.clear();
2856    Instruction *I = nullptr;
2857    unsigned BitCode = Stream.readRecord(Code, Record);
2858    switch (BitCode) {
2859    default: // Default behavior: reject
2860      return Error("Invalid value");
2861    case bitc::FUNC_CODE_DECLAREBLOCKS:     // DECLAREBLOCKS: [nblocks]
2862      if (Record.size() < 1 || Record[0] == 0)
2863        return Error("Invalid record");
2864      // Create all the basic blocks for the function.
2865      FunctionBBs.resize(Record[0]);
2866      for (unsigned i = 0, e = FunctionBBs.size(); i != e; ++i)
2867        FunctionBBs[i] = BasicBlock::Create(Context, "", F);
2868      CurBB = FunctionBBs[0];
2869      continue;
2870
2871    case bitc::FUNC_CODE_DEBUG_LOC_AGAIN:  // DEBUG_LOC_AGAIN
2872      // This record indicates that the last instruction is at the same
2873      // location as the previous instruction with a location.
2874      I = nullptr;
2875
2876      // Get the last instruction emitted.
2877      if (CurBB && !CurBB->empty())
2878        I = &CurBB->back();
2879      else if (CurBBNo && FunctionBBs[CurBBNo-1] &&
2880               !FunctionBBs[CurBBNo-1]->empty())
2881        I = &FunctionBBs[CurBBNo-1]->back();
2882
2883      if (!I)
2884        return Error("Invalid record");
2885      I->setDebugLoc(LastLoc);
2886      I = nullptr;
2887      continue;
2888
2889    case bitc::FUNC_CODE_DEBUG_LOC: {      // DEBUG_LOC: [line, col, scope, ia]
2890      I = nullptr;     // Get the last instruction emitted.
2891      if (CurBB && !CurBB->empty())
2892        I = &CurBB->back();
2893      else if (CurBBNo && FunctionBBs[CurBBNo-1] &&
2894               !FunctionBBs[CurBBNo-1]->empty())
2895        I = &FunctionBBs[CurBBNo-1]->back();
2896      if (!I || Record.size() < 4)
2897        return Error("Invalid record");
2898
2899      unsigned Line = Record[0], Col = Record[1];
2900      unsigned ScopeID = Record[2], IAID = Record[3];
2901
2902      MDNode *Scope = nullptr, *IA = nullptr;
2903      if (ScopeID) Scope = cast<MDNode>(MDValueList.getValueFwdRef(ScopeID-1));
2904      if (IAID)    IA = cast<MDNode>(MDValueList.getValueFwdRef(IAID-1));
2905      LastLoc = DebugLoc::get(Line, Col, Scope, IA);
2906      I->setDebugLoc(LastLoc);
2907      I = nullptr;
2908      continue;
2909    }
2910
2911    case bitc::FUNC_CODE_INST_BINOP: {    // BINOP: [opval, ty, opval, opcode]
2912      unsigned OpNum = 0;
2913      Value *LHS, *RHS;
2914      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
2915          getValue(Record, OpNum, LHS->getType(), RHS) ||
2916          OpNum+1 > Record.size())
2917        return Error("Invalid record");
2918
2919      int Opc = GetDecodedBinaryOpcode(Record[OpNum++], LHS->getType());
2920      if (Opc == -1)
2921        return Error("Invalid record");
2922      I = BinaryOperator::Create((Instruction::BinaryOps)Opc, LHS, RHS);
2923      InstructionList.push_back(I);
2924      if (OpNum < Record.size()) {
2925        if (Opc == Instruction::Add ||
2926            Opc == Instruction::Sub ||
2927            Opc == Instruction::Mul ||
2928            Opc == Instruction::Shl) {
2929          if (Record[OpNum] & (1 << bitc::OBO_NO_SIGNED_WRAP))
2930            cast<BinaryOperator>(I)->setHasNoSignedWrap(true);
2931          if (Record[OpNum] & (1 << bitc::OBO_NO_UNSIGNED_WRAP))
2932            cast<BinaryOperator>(I)->setHasNoUnsignedWrap(true);
2933        } else if (Opc == Instruction::SDiv ||
2934                   Opc == Instruction::UDiv ||
2935                   Opc == Instruction::LShr ||
2936                   Opc == Instruction::AShr) {
2937          if (Record[OpNum] & (1 << bitc::PEO_EXACT))
2938            cast<BinaryOperator>(I)->setIsExact(true);
2939        }
2940      }
2941      break;
2942    }
2943    case bitc::FUNC_CODE_INST_CAST: {    // CAST: [opval, opty, destty, castopc]
2944      unsigned OpNum = 0;
2945      Value *Op;
2946      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
2947          OpNum+2 != Record.size())
2948        return Error("Invalid record");
2949
2950      Type *ResTy = getTypeByID(Record[OpNum]);
2951      int Opc = GetDecodedCastOpcode(Record[OpNum+1]);
2952      if (Opc == -1 || !ResTy)
2953        return Error("Invalid record");
2954      I = CastInst::Create((Instruction::CastOps)Opc, Op, ResTy);
2955      InstructionList.push_back(I);
2956      break;
2957    }
2958    case bitc::FUNC_CODE_INST_INBOUNDS_GEP_OLD:
2959    case bitc::FUNC_CODE_INST_GEP_OLD: // GEP: [n x operands]
2960    case bitc::FUNC_CODE_INST_GEP: { // GEP: [n x operands]
2961      unsigned OpNum = 0;
2962
2963      Type *Ty;
2964      bool InBounds;
2965
2966      if (BitCode == bitc::FUNC_CODE_INST_GEP) {
2967        InBounds = Record[OpNum++];
2968        Ty = getTypeByID(Record[OpNum++]);
2969      } else {
2970        InBounds = BitCode == bitc::FUNC_CODE_INST_INBOUNDS_GEP_OLD;
2971        Ty = nullptr;
2972      }
2973
2974      Value *BasePtr;
2975      if (getValueTypePair(Record, OpNum, NextValueNo, BasePtr))
2976        return Error("Invalid record");
2977
2978      if (Ty &&
2979          Ty !=
2980              cast<SequentialType>(BasePtr->getType()->getScalarType())
2981                  ->getElementType())
2982        return Error(
2983            "Explicit gep type does not match pointee type of pointer operand");
2984
2985      SmallVector<Value*, 16> GEPIdx;
2986      while (OpNum != Record.size()) {
2987        Value *Op;
2988        if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2989          return Error("Invalid record");
2990        GEPIdx.push_back(Op);
2991      }
2992
2993      I = GetElementPtrInst::Create(Ty, BasePtr, GEPIdx);
2994
2995      InstructionList.push_back(I);
2996      if (InBounds)
2997        cast<GetElementPtrInst>(I)->setIsInBounds(true);
2998      break;
2999    }
3000
3001    case bitc::FUNC_CODE_INST_EXTRACTVAL: {
3002                                       // EXTRACTVAL: [opty, opval, n x indices]
3003      unsigned OpNum = 0;
3004      Value *Agg;
3005      if (getValueTypePair(Record, OpNum, NextValueNo, Agg))
3006        return Error("Invalid record");
3007
3008      SmallVector<unsigned, 4> EXTRACTVALIdx;
3009      for (unsigned RecSize = Record.size();
3010           OpNum != RecSize; ++OpNum) {
3011        uint64_t Index = Record[OpNum];
3012        if ((unsigned)Index != Index)
3013          return Error("Invalid value");
3014        EXTRACTVALIdx.push_back((unsigned)Index);
3015      }
3016
3017      I = ExtractValueInst::Create(Agg, EXTRACTVALIdx);
3018      InstructionList.push_back(I);
3019      break;
3020    }
3021
3022    case bitc::FUNC_CODE_INST_INSERTVAL: {
3023                           // INSERTVAL: [opty, opval, opty, opval, n x indices]
3024      unsigned OpNum = 0;
3025      Value *Agg;
3026      if (getValueTypePair(Record, OpNum, NextValueNo, Agg))
3027        return Error("Invalid record");
3028      Value *Val;
3029      if (getValueTypePair(Record, OpNum, NextValueNo, Val))
3030        return Error("Invalid record");
3031
3032      SmallVector<unsigned, 4> INSERTVALIdx;
3033      for (unsigned RecSize = Record.size();
3034           OpNum != RecSize; ++OpNum) {
3035        uint64_t Index = Record[OpNum];
3036        if ((unsigned)Index != Index)
3037          return Error("Invalid value");
3038        INSERTVALIdx.push_back((unsigned)Index);
3039      }
3040
3041      I = InsertValueInst::Create(Agg, Val, INSERTVALIdx);
3042      InstructionList.push_back(I);
3043      break;
3044    }
3045
3046    case bitc::FUNC_CODE_INST_SELECT: { // SELECT: [opval, ty, opval, opval]
3047      // obsolete form of select
3048      // handles select i1 ... in old bitcode
3049      unsigned OpNum = 0;
3050      Value *TrueVal, *FalseVal, *Cond;
3051      if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
3052          getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
3053          getValue(Record, OpNum, Type::getInt1Ty(Context), Cond))
3054        return Error("Invalid record");
3055
3056      I = SelectInst::Create(Cond, TrueVal, FalseVal);
3057      InstructionList.push_back(I);
3058      break;
3059    }
3060
3061    case bitc::FUNC_CODE_INST_VSELECT: {// VSELECT: [ty,opval,opval,predty,pred]
3062      // new form of select
3063      // handles select i1 or select [N x i1]
3064      unsigned OpNum = 0;
3065      Value *TrueVal, *FalseVal, *Cond;
3066      if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
3067          getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
3068          getValueTypePair(Record, OpNum, NextValueNo, Cond))
3069        return Error("Invalid record");
3070
3071      // select condition can be either i1 or [N x i1]
3072      if (VectorType* vector_type =
3073          dyn_cast<VectorType>(Cond->getType())) {
3074        // expect <n x i1>
3075        if (vector_type->getElementType() != Type::getInt1Ty(Context))
3076          return Error("Invalid type for value");
3077      } else {
3078        // expect i1
3079        if (Cond->getType() != Type::getInt1Ty(Context))
3080          return Error("Invalid type for value");
3081      }
3082
3083      I = SelectInst::Create(Cond, TrueVal, FalseVal);
3084      InstructionList.push_back(I);
3085      break;
3086    }
3087
3088    case bitc::FUNC_CODE_INST_EXTRACTELT: { // EXTRACTELT: [opty, opval, opval]
3089      unsigned OpNum = 0;
3090      Value *Vec, *Idx;
3091      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
3092          getValue(Record, OpNum, Type::getInt32Ty(Context), Idx))
3093        return Error("Invalid record");
3094      I = ExtractElementInst::Create(Vec, Idx);
3095      InstructionList.push_back(I);
3096      break;
3097    }
3098
3099    case bitc::FUNC_CODE_INST_INSERTELT: { // INSERTELT: [ty, opval,opval,opval]
3100      unsigned OpNum = 0;
3101      Value *Vec, *Elt, *Idx;
3102      if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
3103          getValue(Record, OpNum,
3104                   cast<VectorType>(Vec->getType())->getElementType(), Elt) ||
3105          getValue(Record, OpNum, Type::getInt32Ty(Context), Idx))
3106        return Error("Invalid record");
3107      I = InsertElementInst::Create(Vec, Elt, Idx);
3108      InstructionList.push_back(I);
3109      break;
3110    }
3111
3112    case bitc::FUNC_CODE_INST_SHUFFLEVEC: {// SHUFFLEVEC: [opval,ty,opval,opval]
3113      unsigned OpNum = 0;
3114      Value *Vec1, *Vec2, *Mask;
3115      if (getValueTypePair(Record, OpNum, NextValueNo, Vec1) ||
3116          getValue(Record, OpNum, Vec1->getType(), Vec2))
3117        return Error("Invalid record");
3118
3119      if (getValueTypePair(Record, OpNum, NextValueNo, Mask))
3120        return Error("Invalid record");
3121      I = new ShuffleVectorInst(Vec1, Vec2, Mask);
3122      InstructionList.push_back(I);
3123      break;
3124    }
3125
3126    case bitc::FUNC_CODE_INST_CMP:   // CMP: [opty, opval, opval, pred]
3127      // Old form of ICmp/FCmp returning bool
3128      // Existed to differentiate between icmp/fcmp and vicmp/vfcmp which were
3129      // both legal on vectors but had different behaviour.
3130    case bitc::FUNC_CODE_INST_CMP2: { // CMP2: [opty, opval, opval, pred]
3131      // FCmp/ICmp returning bool or vector of bool
3132
3133      unsigned OpNum = 0;
3134      Value *LHS, *RHS;
3135      if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
3136          getValue(Record, OpNum, LHS->getType(), RHS) ||
3137          OpNum+1 != Record.size())
3138        return Error("Invalid record");
3139
3140      if (LHS->getType()->isFPOrFPVectorTy())
3141        I = new FCmpInst((FCmpInst::Predicate)Record[OpNum], LHS, RHS);
3142      else
3143        I = new ICmpInst((ICmpInst::Predicate)Record[OpNum], LHS, RHS);
3144      InstructionList.push_back(I);
3145      break;
3146    }
3147
3148    case bitc::FUNC_CODE_INST_RET: // RET: [opty,opval<optional>]
3149      {
3150        unsigned Size = Record.size();
3151        if (Size == 0) {
3152          I = ReturnInst::Create(Context);
3153          InstructionList.push_back(I);
3154          break;
3155        }
3156
3157        unsigned OpNum = 0;
3158        Value *Op = nullptr;
3159        if (getValueTypePair(Record, OpNum, NextValueNo, Op))
3160          return Error("Invalid record");
3161        if (OpNum != Record.size())
3162          return Error("Invalid record");
3163
3164        I = ReturnInst::Create(Context, Op);
3165        InstructionList.push_back(I);
3166        break;
3167      }
3168    case bitc::FUNC_CODE_INST_BR: { // BR: [bb#, bb#, opval] or [bb#]
3169      if (Record.size() != 1 && Record.size() != 3)
3170        return Error("Invalid record");
3171      BasicBlock *TrueDest = getBasicBlock(Record[0]);
3172      if (!TrueDest)
3173        return Error("Invalid record");
3174
3175      if (Record.size() == 1) {
3176        I = BranchInst::Create(TrueDest);
3177        InstructionList.push_back(I);
3178      }
3179      else {
3180        BasicBlock *FalseDest = getBasicBlock(Record[1]);
3181        Value *Cond = getFnValueByID(Record[2], Type::getInt1Ty(Context));
3182        if (!FalseDest || !Cond)
3183          return Error("Invalid record");
3184        I = BranchInst::Create(TrueDest, FalseDest, Cond);
3185        InstructionList.push_back(I);
3186      }
3187      break;
3188    }
3189    case bitc::FUNC_CODE_INST_SWITCH: { // SWITCH: [opty, op0, op1, ...]
3190      if (Record.size() < 3 || (Record.size() & 1) == 0)
3191        return Error("Invalid record");
3192      Type *OpTy = getTypeByID(Record[0]);
3193      Value *Cond = getFnValueByID(Record[1], OpTy);
3194      BasicBlock *Default = getBasicBlock(Record[2]);
3195      if (!OpTy || !Cond || !Default)
3196        return Error("Invalid record");
3197      unsigned NumCases = (Record.size()-3)/2;
3198      SwitchInst *SI = SwitchInst::Create(Cond, Default, NumCases);
3199      InstructionList.push_back(SI);
3200      for (unsigned i = 0, e = NumCases; i != e; ++i) {
3201        ConstantInt *CaseVal =
3202          dyn_cast_or_null<ConstantInt>(getFnValueByID(Record[3+i*2], OpTy));
3203        BasicBlock *DestBB = getBasicBlock(Record[1+3+i*2]);
3204        if (!CaseVal || !DestBB) {
3205          delete SI;
3206          return Error("Invalid record");
3207        }
3208        SI->addCase(CaseVal, DestBB);
3209      }
3210      I = SI;
3211      break;
3212    }
3213    case bitc::FUNC_CODE_INST_INDIRECTBR: { // INDIRECTBR: [opty, op0, op1, ...]
3214      if (Record.size() < 2)
3215        return Error("Invalid record");
3216      Type *OpTy = getTypeByID(Record[0]);
3217      Value *Address = getFnValueByID(Record[1], OpTy);
3218      if (!OpTy || !Address)
3219        return Error("Invalid record");
3220      unsigned NumDests = Record.size()-2;
3221      IndirectBrInst *IBI = IndirectBrInst::Create(Address, NumDests);
3222      InstructionList.push_back(IBI);
3223      for (unsigned i = 0, e = NumDests; i != e; ++i) {
3224        if (BasicBlock *DestBB = getBasicBlock(Record[2+i])) {
3225          IBI->addDestination(DestBB);
3226        } else {
3227          delete IBI;
3228          return Error("Invalid record");
3229        }
3230      }
3231      I = IBI;
3232      break;
3233    }
3234
3235    case bitc::FUNC_CODE_INST_INVOKE: {
3236      // INVOKE: [attrs, cc, normBB, unwindBB, fnty, op0,op1,op2, ...]
3237      if (Record.size() < 4)
3238        return Error("Invalid record");
3239      AttributeSet PAL = getAttributes(Record[0]);
3240      unsigned CCInfo = Record[1];
3241      BasicBlock *NormalBB = getBasicBlock(Record[2]);
3242      BasicBlock *UnwindBB = getBasicBlock(Record[3]);
3243
3244      unsigned OpNum = 4;
3245      Value *Callee;
3246      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
3247        return Error("Invalid record");
3248
3249      PointerType *CalleeTy = dyn_cast<PointerType>(Callee->getType());
3250      FunctionType *FTy = !CalleeTy ? nullptr :
3251        dyn_cast<FunctionType>(CalleeTy->getElementType());
3252
3253      // Check that the right number of fixed parameters are here.
3254      if (!FTy || !NormalBB || !UnwindBB ||
3255          Record.size() < OpNum+FTy->getNumParams())
3256        return Error("Invalid record");
3257
3258      SmallVector<Value*, 16> Ops;
3259      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
3260        Ops.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
3261        if (!Ops.back())
3262          return Error("Invalid record");
3263      }
3264
3265      if (!FTy->isVarArg()) {
3266        if (Record.size() != OpNum)
3267          return Error("Invalid record");
3268      } else {
3269        // Read type/value pairs for varargs params.
3270        while (OpNum != Record.size()) {
3271          Value *Op;
3272          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
3273            return Error("Invalid record");
3274          Ops.push_back(Op);
3275        }
3276      }
3277
3278      I = InvokeInst::Create(Callee, NormalBB, UnwindBB, Ops);
3279      InstructionList.push_back(I);
3280      cast<InvokeInst>(I)->setCallingConv(
3281        static_cast<CallingConv::ID>(CCInfo));
3282      cast<InvokeInst>(I)->setAttributes(PAL);
3283      break;
3284    }
3285    case bitc::FUNC_CODE_INST_RESUME: { // RESUME: [opval]
3286      unsigned Idx = 0;
3287      Value *Val = nullptr;
3288      if (getValueTypePair(Record, Idx, NextValueNo, Val))
3289        return Error("Invalid record");
3290      I = ResumeInst::Create(Val);
3291      InstructionList.push_back(I);
3292      break;
3293    }
3294    case FUNC_CODE_INST_UNWIND_2_7: { // UNWIND_OLD
3295      // 'unwind' instruction has been removed in LLVM 3.1
3296      // Replace 'unwind' with 'landingpad' and 'resume'.
3297      Type *ExnTy = StructType::get(Type::getInt8PtrTy(Context),
3298                                    Type::getInt32Ty(Context), nullptr);
3299      Constant *PersFn =
3300        F->getParent()->
3301        getOrInsertFunction("__gcc_personality_v0",
3302                          FunctionType::get(Type::getInt32Ty(Context), true));
3303
3304      LandingPadInst *LP = LandingPadInst::Create(ExnTy, PersFn, 1);
3305      LP->setCleanup(true);
3306
3307      CurBB->getInstList().push_back(LP);
3308      I = ResumeInst::Create(LP);
3309      InstructionList.push_back(I);
3310      break;
3311    }
3312    case bitc::FUNC_CODE_INST_UNREACHABLE: // UNREACHABLE
3313      I = new UnreachableInst(Context);
3314      InstructionList.push_back(I);
3315      break;
3316    case bitc::FUNC_CODE_INST_PHI: { // PHI: [ty, val0,bb0, ...]
3317      if (Record.size() < 1 || ((Record.size()-1)&1))
3318        return Error("Invalid record");
3319      Type *Ty = getTypeByID(Record[0]);
3320      if (!Ty)
3321        return Error("Invalid record");
3322
3323      PHINode *PN = PHINode::Create(Ty, (Record.size()-1)/2);
3324      InstructionList.push_back(PN);
3325
3326      for (unsigned i = 0, e = Record.size()-1; i != e; i += 2) {
3327        Value *V = getFnValueByID(Record[1+i], Ty);
3328        BasicBlock *BB = getBasicBlock(Record[2+i]);
3329        if (!V || !BB)
3330          return Error("Invalid record");
3331        PN->addIncoming(V, BB);
3332      }
3333      I = PN;
3334      break;
3335    }
3336
3337    case bitc::FUNC_CODE_INST_LANDINGPAD: {
3338      // LANDINGPAD: [ty, val, val, num, (id0,val0 ...)?]
3339      unsigned Idx = 0;
3340      if (Record.size() < 4)
3341        return Error("Invalid record");
3342      Type *Ty = getTypeByID(Record[Idx++]);
3343      if (!Ty)
3344        return Error("Invalid record");
3345      Value *PersFn = nullptr;
3346      if (getValueTypePair(Record, Idx, NextValueNo, PersFn))
3347        return Error("Invalid record");
3348
3349      bool IsCleanup = !!Record[Idx++];
3350      unsigned NumClauses = Record[Idx++];
3351      LandingPadInst *LP = LandingPadInst::Create(Ty, PersFn, NumClauses);
3352      LP->setCleanup(IsCleanup);
3353      for (unsigned J = 0; J != NumClauses; ++J) {
3354        LandingPadInst::ClauseType CT =
3355          LandingPadInst::ClauseType(Record[Idx++]); (void)CT;
3356        Value *Val;
3357
3358        if (getValueTypePair(Record, Idx, NextValueNo, Val)) {
3359          delete LP;
3360          return Error("Invalid record");
3361        }
3362
3363        assert((CT != LandingPadInst::Catch ||
3364                !isa<ArrayType>(Val->getType())) &&
3365               "Catch clause has a invalid type!");
3366        assert((CT != LandingPadInst::Filter ||
3367                isa<ArrayType>(Val->getType())) &&
3368               "Filter clause has invalid type!");
3369        LP->addClause(cast<Constant>(Val));
3370      }
3371
3372      I = LP;
3373      InstructionList.push_back(I);
3374      break;
3375    }
3376
3377    case bitc::FUNC_CODE_INST_ALLOCA: { // ALLOCA: [instty, opty, op, align]
3378      if (Record.size() != 4)
3379        return Error("Invalid record");
3380      PointerType *Ty =
3381        dyn_cast_or_null<PointerType>(getTypeByID(Record[0]));
3382      Type *OpTy = getTypeByID(Record[1]);
3383      Value *Size = getFnValueByID(Record[2], OpTy);
3384      unsigned Align = Record[3];
3385      if (!Ty || !Size)
3386        return Error("Invalid record");
3387      I = new AllocaInst(Ty->getElementType(), Size, (1 << Align) >> 1);
3388      InstructionList.push_back(I);
3389      break;
3390    }
3391    case bitc::FUNC_CODE_INST_LOAD: { // LOAD: [opty, op, align, vol]
3392      unsigned OpNum = 0;
3393      Value *Op;
3394      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
3395          OpNum+2 != Record.size())
3396        return Error("Invalid record");
3397
3398      I = new LoadInst(Op, "", Record[OpNum+1], (1 << Record[OpNum]) >> 1);
3399      InstructionList.push_back(I);
3400      break;
3401    }
3402    case bitc::FUNC_CODE_INST_LOADATOMIC: {
3403       // LOADATOMIC: [opty, op, align, vol, ordering, synchscope]
3404      unsigned OpNum = 0;
3405      Value *Op;
3406      if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
3407          OpNum+4 != Record.size())
3408        return Error("Invalid record");
3409
3410      AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]);
3411      if (Ordering == NotAtomic || Ordering == Release ||
3412          Ordering == AcquireRelease)
3413        return Error("Invalid record");
3414      if (Ordering != NotAtomic && Record[OpNum] == 0)
3415        return Error("Invalid record");
3416      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+3]);
3417
3418      I = new LoadInst(Op, "", Record[OpNum+1], (1 << Record[OpNum]) >> 1,
3419                       Ordering, SynchScope);
3420      InstructionList.push_back(I);
3421      break;
3422    }
3423    case bitc::FUNC_CODE_INST_STORE: { // STORE2:[ptrty, ptr, val, align, vol]
3424      unsigned OpNum = 0;
3425      Value *Val, *Ptr;
3426      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
3427          getValue(Record, OpNum,
3428                    cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
3429          OpNum+2 != Record.size())
3430        return Error("Invalid record");
3431
3432      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1);
3433      InstructionList.push_back(I);
3434      break;
3435    }
3436    case bitc::FUNC_CODE_INST_STOREATOMIC: {
3437      // STOREATOMIC: [ptrty, ptr, val, align, vol, ordering, synchscope]
3438      unsigned OpNum = 0;
3439      Value *Val, *Ptr;
3440      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
3441          getValue(Record, OpNum,
3442                    cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
3443          OpNum+4 != Record.size())
3444        return Error("Invalid record");
3445
3446      AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]);
3447      if (Ordering == NotAtomic || Ordering == Acquire ||
3448          Ordering == AcquireRelease)
3449        return Error("Invalid record");
3450      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+3]);
3451      if (Ordering != NotAtomic && Record[OpNum] == 0)
3452        return Error("Invalid record");
3453
3454      I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1,
3455                        Ordering, SynchScope);
3456      InstructionList.push_back(I);
3457      break;
3458    }
3459    case bitc::FUNC_CODE_INST_CMPXCHG: {
3460      // CMPXCHG:[ptrty, ptr, cmp, new, vol, ordering, synchscope]
3461      unsigned OpNum = 0;
3462      Value *Ptr, *Cmp, *New;
3463      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
3464          getValue(Record, OpNum,
3465                    cast<PointerType>(Ptr->getType())->getElementType(), Cmp) ||
3466          getValue(Record, OpNum,
3467                    cast<PointerType>(Ptr->getType())->getElementType(), New) ||
3468          OpNum+3 != Record.size())
3469        return Error("Invalid record");
3470      AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+1]);
3471      if (Ordering == NotAtomic || Ordering == Unordered)
3472        return Error("Invalid record");
3473      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+2]);
3474      I = new AtomicCmpXchgInst(Ptr, Cmp, New, Ordering, Ordering, SynchScope);
3475      cast<AtomicCmpXchgInst>(I)->setVolatile(Record[OpNum]);
3476      InstructionList.push_back(I);
3477      break;
3478    }
3479    case bitc::FUNC_CODE_INST_ATOMICRMW: {
3480      // ATOMICRMW:[ptrty, ptr, val, op, vol, ordering, synchscope]
3481      unsigned OpNum = 0;
3482      Value *Ptr, *Val;
3483      if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
3484          getValue(Record, OpNum,
3485                    cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
3486          OpNum+4 != Record.size())
3487        return Error("Invalid record");
3488      AtomicRMWInst::BinOp Operation = GetDecodedRMWOperation(Record[OpNum]);
3489      if (Operation < AtomicRMWInst::FIRST_BINOP ||
3490          Operation > AtomicRMWInst::LAST_BINOP)
3491        return Error("Invalid record");
3492      AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]);
3493      if (Ordering == NotAtomic || Ordering == Unordered)
3494        return Error("Invalid record");
3495      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+3]);
3496      I = new AtomicRMWInst(Operation, Ptr, Val, Ordering, SynchScope);
3497      cast<AtomicRMWInst>(I)->setVolatile(Record[OpNum+1]);
3498      InstructionList.push_back(I);
3499      break;
3500    }
3501    case bitc::FUNC_CODE_INST_FENCE: { // FENCE:[ordering, synchscope]
3502      if (2 != Record.size())
3503        return Error("Invalid record");
3504      AtomicOrdering Ordering = GetDecodedOrdering(Record[0]);
3505      if (Ordering == NotAtomic || Ordering == Unordered ||
3506          Ordering == Monotonic)
3507        return Error("Invalid record");
3508      SynchronizationScope SynchScope = GetDecodedSynchScope(Record[1]);
3509      I = new FenceInst(Context, Ordering, SynchScope);
3510      InstructionList.push_back(I);
3511      break;
3512    }
3513    case bitc::FUNC_CODE_INST_CALL: {
3514      // CALL: [paramattrs, cc, fnty, fnid, arg0, arg1...]
3515      if (Record.size() < 3)
3516        return Error("Invalid record");
3517
3518      AttributeSet PAL = getAttributes(Record[0]);
3519      unsigned CCInfo = Record[1];
3520
3521      unsigned OpNum = 2;
3522      Value *Callee;
3523      if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
3524        return Error("Invalid record");
3525
3526      PointerType *OpTy = dyn_cast<PointerType>(Callee->getType());
3527      FunctionType *FTy = nullptr;
3528      if (OpTy) FTy = dyn_cast<FunctionType>(OpTy->getElementType());
3529      if (!FTy || Record.size() < FTy->getNumParams()+OpNum)
3530        return Error("Invalid record");
3531
3532      SmallVector<Value*, 16> Args;
3533      // Read the fixed params.
3534      for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
3535        if (FTy->getParamType(i)->isLabelTy())
3536          Args.push_back(getBasicBlock(Record[OpNum]));
3537        else
3538          Args.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
3539        if (!Args.back())
3540          return Error("Invalid record");
3541      }
3542
3543      // Read type/value pairs for varargs params.
3544      if (!FTy->isVarArg()) {
3545        if (OpNum != Record.size())
3546          return Error("Invalid record");
3547      } else {
3548        while (OpNum != Record.size()) {
3549          Value *Op;
3550          if (getValueTypePair(Record, OpNum, NextValueNo, Op))
3551            return Error("Invalid record");
3552          Args.push_back(Op);
3553        }
3554      }
3555
3556      I = CallInst::Create(Callee, Args);
3557      InstructionList.push_back(I);
3558      cast<CallInst>(I)->setCallingConv(
3559        static_cast<CallingConv::ID>(CCInfo>>1));
3560      cast<CallInst>(I)->setTailCall(CCInfo & 1);
3561      cast<CallInst>(I)->setAttributes(PAL);
3562      break;
3563    }
3564    case bitc::FUNC_CODE_INST_VAARG: { // VAARG: [valistty, valist, instty]
3565      if (Record.size() < 3)
3566        return Error("Invalid record");
3567      Type *OpTy = getTypeByID(Record[0]);
3568      Value *Op = getFnValueByID(Record[1], OpTy);
3569      Type *ResTy = getTypeByID(Record[2]);
3570      if (!OpTy || !Op || !ResTy)
3571        return Error("Invalid record");
3572      I = new VAArgInst(Op, ResTy);
3573      InstructionList.push_back(I);
3574      break;
3575    }
3576    }
3577
3578    // Add instruction to end of current BB.  If there is no current BB, reject
3579    // this file.
3580    if (!CurBB) {
3581      delete I;
3582      return Error("Invalid instruction with no BB");
3583    }
3584    CurBB->getInstList().push_back(I);
3585
3586    // If this was a terminator instruction, move to the next block.
3587    if (isa<TerminatorInst>(I)) {
3588      ++CurBBNo;
3589      CurBB = CurBBNo < FunctionBBs.size() ? FunctionBBs[CurBBNo] : nullptr;
3590    }
3591
3592    // Non-void values get registered in the value table for future use.
3593    if (I && !I->getType()->isVoidTy())
3594      ValueList.AssignValue(I, NextValueNo++);
3595  }
3596
3597  // Check the function list for unresolved values.
3598  if (Argument *A = dyn_cast<Argument>(ValueList.back())) {
3599    if (!A->getParent()) {
3600      // We found at least one unresolved value.  Nuke them all to avoid leaks.
3601      for (unsigned i = ModuleValueListSize, e = ValueList.size(); i != e; ++i){
3602        if ((A = dyn_cast_or_null<Argument>(ValueList[i])) && !A->getParent()) {
3603          A->replaceAllUsesWith(UndefValue::get(A->getType()));
3604          delete A;
3605        }
3606      }
3607      return Error("Never resolved value found in function");
3608    }
3609  }
3610
3611  // FIXME: Check for unresolved forward-declared metadata references
3612  // and clean up leaks.
3613
3614  // See if anything took the address of blocks in this function.  If so,
3615  // resolve them now.
3616  DenseMap<Function*, std::vector<BlockAddrRefTy> >::iterator BAFRI =
3617    BlockAddrFwdRefs.find(F);
3618  if (BAFRI != BlockAddrFwdRefs.end()) {
3619    std::vector<BlockAddrRefTy> &RefList = BAFRI->second;
3620    for (unsigned i = 0, e = RefList.size(); i != e; ++i) {
3621      unsigned BlockIdx = RefList[i].first;
3622      if (BlockIdx >= FunctionBBs.size())
3623        return Error("Invalid ID");
3624
3625      GlobalVariable *FwdRef = RefList[i].second;
3626      FwdRef->replaceAllUsesWith(BlockAddress::get(F, FunctionBBs[BlockIdx]));
3627      FwdRef->eraseFromParent();
3628    }
3629
3630    BlockAddrFwdRefs.erase(BAFRI);
3631  }
3632
3633  // Trim the value list down to the size it was before we parsed this function.
3634  ValueList.shrinkTo(ModuleValueListSize);
3635  MDValueList.shrinkTo(ModuleMDValueListSize);
3636  std::vector<BasicBlock*>().swap(FunctionBBs);
3637  return std::error_code();
3638}
3639
3640//===----------------------------------------------------------------------===//
3641// GVMaterializer implementation
3642//===----------------------------------------------------------------------===//
3643
3644void BitcodeReader::releaseBuffer() { Buffer.release(); }
3645
3646std::error_code BitcodeReader::materialize(GlobalValue *GV) {
3647  if (std::error_code EC = materializeMetadata())
3648    return EC;
3649
3650  Function *F = dyn_cast<Function>(GV);
3651  // If it's not a function or is already material, ignore the request.
3652  if (!F || !F->isMaterializable())
3653    return std::error_code();
3654
3655  DenseMap<Function*, uint64_t>::iterator DFII = DeferredFunctionInfo.find(F);
3656  assert(DFII != DeferredFunctionInfo.end() && "Deferred function not found!");
3657
3658  // Move the bit stream to the saved position of the deferred function body.
3659  Stream.JumpToBit(DFII->second);
3660
3661  if (std::error_code EC = ParseFunctionBody(F))
3662    return EC;
3663  F->setIsMaterializable(false);
3664
3665  // Upgrade any old intrinsic calls in the function.
3666  for (UpgradedIntrinsicMap::iterator I = UpgradedIntrinsics.begin(),
3667       E = UpgradedIntrinsics.end(); I != E; ++I) {
3668    if (I->first != I->second) {
3669      for (auto UI = I->first->user_begin(), UE = I->first->user_end();
3670           UI != UE;) {
3671        if (CallInst* CI = dyn_cast<CallInst>(*UI++))
3672          UpgradeIntrinsicCall(CI, I->second);
3673      }
3674    }
3675  }
3676
3677  return std::error_code();
3678}
3679
3680bool BitcodeReader::isDematerializable(const GlobalValue *GV) const {
3681  const Function *F = dyn_cast<Function>(GV);
3682  if (!F || F->isDeclaration())
3683    return false;
3684  return DeferredFunctionInfo.count(const_cast<Function*>(F));
3685}
3686
3687void BitcodeReader::Dematerialize(GlobalValue *GV) {
3688  Function *F = dyn_cast<Function>(GV);
3689  // If this function isn't dematerializable, this is a noop.
3690  if (!F || !isDematerializable(F))
3691    return;
3692
3693  assert(DeferredFunctionInfo.count(F) && "No info to read function later?");
3694
3695  // Just forget the function body, we can remat it later.
3696  F->deleteBody();
3697  F->setIsMaterializable(true);
3698}
3699
3700std::error_code BitcodeReader::MaterializeModule(Module *M) {
3701  assert(M == TheModule &&
3702         "Can only Materialize the Module this BitcodeReader is attached to.");
3703  // Iterate over the module, deserializing any functions that are still on
3704  // disk.
3705  for (Module::iterator F = TheModule->begin(), E = TheModule->end();
3706       F != E; ++F) {
3707    if (std::error_code EC = materialize(F))
3708      return EC;
3709  }
3710  // At this point, if there are any function bodies, the current bit is
3711  // pointing to the END_BLOCK record after them. Now make sure the rest
3712  // of the bits in the module have been read.
3713  if (NextUnreadBit)
3714    ParseModule(true);
3715
3716  // Upgrade any intrinsic calls that slipped through (should not happen!) and
3717  // delete the old functions to clean up. We can't do this unless the entire
3718  // module is materialized because there could always be another function body
3719  // with calls to the old function.
3720  for (std::vector<std::pair<Function*, Function*> >::iterator I =
3721       UpgradedIntrinsics.begin(), E = UpgradedIntrinsics.end(); I != E; ++I) {
3722    if (I->first != I->second) {
3723      for (auto UI = I->first->user_begin(), UE = I->first->user_end();
3724           UI != UE;) {
3725        if (CallInst* CI = dyn_cast<CallInst>(*UI++))
3726          UpgradeIntrinsicCall(CI, I->second);
3727      }
3728      if (!I->first->use_empty())
3729        I->first->replaceAllUsesWith(I->second);
3730      I->first->eraseFromParent();
3731    }
3732  }
3733  std::vector<std::pair<Function*, Function*> >().swap(UpgradedIntrinsics);
3734
3735  // Upgrade to new EH scheme. N.B. This will go away in 3.1.
3736  UpgradeExceptionHandling(M);
3737
3738  // Check debug info intrinsics.
3739  CheckDebugInfoIntrinsics(TheModule);
3740
3741  return std::error_code();
3742}
3743
3744std::vector<StructType *> BitcodeReader::getIdentifiedStructTypes() const {
3745  return IdentifiedStructTypes;
3746}
3747
3748std::error_code BitcodeReader::InitStream() {
3749  if (LazyStreamer)
3750    return InitLazyStream();
3751  return InitStreamFromBuffer();
3752}
3753
3754std::error_code BitcodeReader::InitStreamFromBuffer() {
3755  const unsigned char *BufPtr = (const unsigned char*)Buffer->getBufferStart();
3756  const unsigned char *BufEnd = BufPtr+Buffer->getBufferSize();
3757
3758  if (Buffer->getBufferSize() & 3)
3759    return Error("Invalid bitcode signature");
3760
3761  // If we have a wrapper header, parse it and ignore the non-bc file contents.
3762  // The magic number is 0x0B17C0DE stored in little endian.
3763  if (isBitcodeWrapper(BufPtr, BufEnd))
3764    if (SkipBitcodeWrapperHeader(BufPtr, BufEnd, true))
3765      return Error("Invalid bitcode wrapper header");
3766
3767  StreamFile.reset(new BitstreamReader(BufPtr, BufEnd));
3768  Stream.init(&*StreamFile);
3769
3770  return std::error_code();
3771}
3772
3773std::error_code BitcodeReader::InitLazyStream() {
3774  // Check and strip off the bitcode wrapper; BitstreamReader expects never to
3775  // see it.
3776  auto OwnedBytes = llvm::make_unique<StreamingMemoryObject>(LazyStreamer);
3777  StreamingMemoryObject &Bytes = *OwnedBytes;
3778  StreamFile = llvm::make_unique<BitstreamReader>(std::move(OwnedBytes));
3779  Stream.init(&*StreamFile);
3780
3781  unsigned char buf[16];
3782  if (Bytes.readBytes(buf, 16, 0) != 16)
3783    return Error("Invalid bitcode signature");
3784
3785  if (!isBitcode(buf, buf + 16))
3786    return Error("Invalid bitcode signature");
3787
3788  if (isBitcodeWrapper(buf, buf + 4)) {
3789    const unsigned char *bitcodeStart = buf;
3790    const unsigned char *bitcodeEnd = buf + 16;
3791    SkipBitcodeWrapperHeader(bitcodeStart, bitcodeEnd, false);
3792    Bytes.dropLeadingBytes(bitcodeStart - buf);
3793    Bytes.setKnownObjectSize(bitcodeEnd - bitcodeStart);
3794  }
3795  return std::error_code();
3796}
3797
3798namespace {
3799class BitcodeErrorCategoryType : public std::error_category {
3800  const char *name() const LLVM_NOEXCEPT override {
3801    return "llvm.bitcode";
3802  }
3803  std::string message(int IE) const override {
3804    BitcodeError E = static_cast<BitcodeError>(IE);
3805    switch (E) {
3806    case BitcodeError::InvalidBitcodeSignature:
3807      return "Invalid bitcode signature";
3808    case BitcodeError::CorruptedBitcode:
3809      return "Corrupted bitcode";
3810    }
3811    llvm_unreachable("Unknown error type!");
3812  }
3813};
3814}
3815
3816static ManagedStatic<BitcodeErrorCategoryType> ErrorCategory;
3817
3818const std::error_category &BitcodeReader::BitcodeErrorCategory() {
3819  return *ErrorCategory;
3820}
3821
3822//===----------------------------------------------------------------------===//
3823// External interface
3824//===----------------------------------------------------------------------===//
3825
3826/// getLazyBitcodeModule - lazy function-at-a-time loading from a file.
3827///
3828static llvm::ErrorOr<llvm::Module *>
3829getLazyBitcodeModuleImpl(std::unique_ptr<MemoryBuffer> &&Buffer,
3830                         LLVMContext &Context, bool WillMaterializeAll,
3831                         DiagnosticHandlerFunction DiagnosticHandler) {
3832  Module *M = new Module(Buffer->getBufferIdentifier(), Context);
3833  BitcodeReader *R =
3834      new BitcodeReader(Buffer.get(), Context, DiagnosticHandler);
3835  M->setMaterializer(R);
3836
3837  auto cleanupOnError = [&](std::error_code EC) {
3838    R->releaseBuffer(); // Never take ownership on error.
3839    delete M;  // Also deletes R.
3840    return EC;
3841  };
3842
3843  if (std::error_code EC = R->ParseBitcodeInto(M))
3844    return cleanupOnError(EC);
3845
3846  Buffer.release(); // The BitcodeReader owns it now.
3847  return M;
3848}
3849
3850llvm::ErrorOr<Module *>
3851llvm_3_0::getLazyBitcodeModule(std::unique_ptr<MemoryBuffer> &&Buffer,
3852                           LLVMContext &Context,
3853                           DiagnosticHandlerFunction DiagnosticHandler) {
3854  return getLazyBitcodeModuleImpl(std::move(Buffer), Context, false,
3855                                  DiagnosticHandler);
3856}
3857
3858/// ParseBitcodeFile - Read the specified bitcode file, returning the module.
3859/// If an error occurs, return null and fill in *ErrMsg if non-null.
3860llvm::ErrorOr<llvm::Module *>
3861llvm_3_0::parseBitcodeFile(MemoryBufferRef Buffer, LLVMContext &Context,
3862                       DiagnosticHandlerFunction DiagnosticHandler) {
3863  std::unique_ptr<MemoryBuffer> Buf = MemoryBuffer::getMemBuffer(Buffer, false);
3864  ErrorOr<Module *> ModuleOrErr = getLazyBitcodeModuleImpl(
3865      std::move(Buf), Context, true, DiagnosticHandler);
3866  if (!ModuleOrErr)
3867    return ModuleOrErr;
3868  Module *M = ModuleOrErr.get();
3869  // Read in the entire module, and destroy the BitcodeReader.
3870  if (std::error_code EC = M->materializeAllPermanently()) {
3871    delete M;
3872    return EC;
3873  }
3874
3875  return M;
3876}
3877
3878std::string
3879llvm_3_0::getBitcodeTargetTriple(MemoryBufferRef Buffer, LLVMContext &Context,
3880                             DiagnosticHandlerFunction DiagnosticHandler) {
3881  std::unique_ptr<MemoryBuffer> Buf = MemoryBuffer::getMemBuffer(Buffer, false);
3882  auto R = llvm::make_unique<BitcodeReader>(Buf.release(), Context,
3883                                            DiagnosticHandler);
3884  ErrorOr<std::string> Triple = R->parseTriple();
3885  if (Triple.getError())
3886    return "";
3887  return Triple.get();
3888}
3889