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1 //===- BitcodeReader.cpp - Internal BitcodeReader implementation ----------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This header defines the BitcodeReader class.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/Bitcode/ReaderWriter.h"
15 #include "BitcodeReader.h"
16 #include "BitReader_3_0.h"
17 #include "llvm/ADT/SmallString.h"
18 #include "llvm/ADT/SmallVector.h"
19 #include "llvm/AutoUpgrade.h"
20 #include "llvm/IR/Constants.h"
21 #include "llvm/IR/DerivedTypes.h"
22 #include "llvm/IR/InlineAsm.h"
23 #include "llvm/IR/IntrinsicInst.h"
24 #include "llvm/IR/IRBuilder.h"
25 #include "llvm/IR/Module.h"
26 #include "llvm/IR/OperandTraits.h"
27 #include "llvm/IR/Operator.h"
28 #include "llvm/ADT/SmallPtrSet.h"
29 #include "llvm/Support/CFG.h"
30 #include "llvm/Support/MathExtras.h"
31 #include "llvm/Support/MemoryBuffer.h"
32 using namespace llvm;
33 using namespace llvm_3_0;
34 
35 #define FUNC_CODE_INST_UNWIND_2_7     14
36 #define eh_exception_2_7             145
37 #define eh_selector_2_7              149
38 
39 #define TYPE_BLOCK_ID_OLD_3_0         10
40 #define TYPE_SYMTAB_BLOCK_ID_OLD_3_0  13
41 #define TYPE_CODE_STRUCT_OLD_3_0      10
42 
43 namespace {
FindExnAndSelIntrinsics(BasicBlock * BB,CallInst * & Exn,CallInst * & Sel,SmallPtrSet<BasicBlock *,8> & Visited)44   void FindExnAndSelIntrinsics(BasicBlock *BB, CallInst *&Exn,
45                                       CallInst *&Sel,
46                                       SmallPtrSet<BasicBlock*, 8> &Visited) {
47     if (!Visited.insert(BB)) return;
48 
49     for (BasicBlock::iterator
50            I = BB->begin(), E = BB->end(); I != E; ++I) {
51       if (CallInst *CI = dyn_cast<CallInst>(I)) {
52         switch (CI->getCalledFunction()->getIntrinsicID()) {
53         default: break;
54         case eh_exception_2_7:
55           assert(!Exn && "Found more than one eh.exception call!");
56           Exn = CI;
57           break;
58         case eh_selector_2_7:
59           assert(!Sel && "Found more than one eh.selector call!");
60           Sel = CI;
61           break;
62         }
63 
64         if (Exn && Sel) return;
65       }
66     }
67 
68     if (Exn && Sel) return;
69 
70     for (succ_iterator I = succ_begin(BB), E = succ_end(BB); I != E; ++I) {
71       FindExnAndSelIntrinsics(*I, Exn, Sel, Visited);
72       if (Exn && Sel) return;
73     }
74   }
75 
76 
77 
78   /// TransferClausesToLandingPadInst - Transfer the exception handling clauses
79   /// from the eh_selector call to the new landingpad instruction.
TransferClausesToLandingPadInst(LandingPadInst * LPI,CallInst * EHSel)80   void TransferClausesToLandingPadInst(LandingPadInst *LPI,
81                                               CallInst *EHSel) {
82     LLVMContext &Context = LPI->getContext();
83     unsigned N = EHSel->getNumArgOperands();
84 
85     for (unsigned i = N - 1; i > 1; --i) {
86       if (const ConstantInt *CI = dyn_cast<ConstantInt>(EHSel->getArgOperand(i))){
87         unsigned FilterLength = CI->getZExtValue();
88         unsigned FirstCatch = i + FilterLength + !FilterLength;
89         assert(FirstCatch <= N && "Invalid filter length");
90 
91         if (FirstCatch < N)
92           for (unsigned j = FirstCatch; j < N; ++j) {
93             Value *Val = EHSel->getArgOperand(j);
94             if (!Val->hasName() || Val->getName() != "llvm.eh.catch.all.value") {
95               LPI->addClause(EHSel->getArgOperand(j));
96             } else {
97               GlobalVariable *GV = cast<GlobalVariable>(Val);
98               LPI->addClause(GV->getInitializer());
99             }
100           }
101 
102         if (!FilterLength) {
103           // Cleanup.
104           LPI->setCleanup(true);
105         } else {
106           // Filter.
107           SmallVector<Constant *, 4> TyInfo;
108           TyInfo.reserve(FilterLength - 1);
109           for (unsigned j = i + 1; j < FirstCatch; ++j)
110             TyInfo.push_back(cast<Constant>(EHSel->getArgOperand(j)));
111           ArrayType *AType =
112             ArrayType::get(!TyInfo.empty() ? TyInfo[0]->getType() :
113                            PointerType::getUnqual(Type::getInt8Ty(Context)),
114                            TyInfo.size());
115           LPI->addClause(ConstantArray::get(AType, TyInfo));
116         }
117 
118         N = i;
119       }
120     }
121 
122     if (N > 2)
123       for (unsigned j = 2; j < N; ++j) {
124         Value *Val = EHSel->getArgOperand(j);
125         if (!Val->hasName() || Val->getName() != "llvm.eh.catch.all.value") {
126           LPI->addClause(EHSel->getArgOperand(j));
127         } else {
128           GlobalVariable *GV = cast<GlobalVariable>(Val);
129           LPI->addClause(GV->getInitializer());
130         }
131       }
132   }
133 
134 
135   /// This function upgrades the old pre-3.0 exception handling system to the new
136   /// one. N.B. This will be removed in 3.1.
UpgradeExceptionHandling(Module * M)137   void UpgradeExceptionHandling(Module *M) {
138     Function *EHException = M->getFunction("llvm.eh.exception");
139     Function *EHSelector = M->getFunction("llvm.eh.selector");
140     if (!EHException || !EHSelector)
141       return;
142 
143     LLVMContext &Context = M->getContext();
144     Type *ExnTy = PointerType::getUnqual(Type::getInt8Ty(Context));
145     Type *SelTy = Type::getInt32Ty(Context);
146     Type *LPadSlotTy = StructType::get(ExnTy, SelTy, NULL);
147 
148     // This map links the invoke instruction with the eh.exception and eh.selector
149     // calls associated with it.
150     DenseMap<InvokeInst*, std::pair<Value*, Value*> > InvokeToIntrinsicsMap;
151     for (Module::iterator
152            I = M->begin(), E = M->end(); I != E; ++I) {
153       Function &F = *I;
154 
155       for (Function::iterator
156              II = F.begin(), IE = F.end(); II != IE; ++II) {
157         BasicBlock *BB = &*II;
158         InvokeInst *Inst = dyn_cast<InvokeInst>(BB->getTerminator());
159         if (!Inst) continue;
160         BasicBlock *UnwindDest = Inst->getUnwindDest();
161         if (UnwindDest->isLandingPad()) continue; // Already converted.
162 
163         SmallPtrSet<BasicBlock*, 8> Visited;
164         CallInst *Exn = 0;
165         CallInst *Sel = 0;
166         FindExnAndSelIntrinsics(UnwindDest, Exn, Sel, Visited);
167         assert(Exn && Sel && "Cannot find eh.exception and eh.selector calls!");
168         InvokeToIntrinsicsMap[Inst] = std::make_pair(Exn, Sel);
169       }
170     }
171 
172     // This map stores the slots where the exception object and selector value are
173     // stored within a function.
174     DenseMap<Function*, std::pair<Value*, Value*> > FnToLPadSlotMap;
175     SmallPtrSet<Instruction*, 32> DeadInsts;
176     for (DenseMap<InvokeInst*, std::pair<Value*, Value*> >::iterator
177            I = InvokeToIntrinsicsMap.begin(), E = InvokeToIntrinsicsMap.end();
178          I != E; ++I) {
179       InvokeInst *Invoke = I->first;
180       BasicBlock *UnwindDest = Invoke->getUnwindDest();
181       Function *F = UnwindDest->getParent();
182       std::pair<Value*, Value*> EHIntrinsics = I->second;
183       CallInst *Exn = cast<CallInst>(EHIntrinsics.first);
184       CallInst *Sel = cast<CallInst>(EHIntrinsics.second);
185 
186       // Store the exception object and selector value in the entry block.
187       Value *ExnSlot = 0;
188       Value *SelSlot = 0;
189       if (!FnToLPadSlotMap[F].first) {
190         BasicBlock *Entry = &F->front();
191         ExnSlot = new AllocaInst(ExnTy, "exn", Entry->getTerminator());
192         SelSlot = new AllocaInst(SelTy, "sel", Entry->getTerminator());
193         FnToLPadSlotMap[F] = std::make_pair(ExnSlot, SelSlot);
194       } else {
195         ExnSlot = FnToLPadSlotMap[F].first;
196         SelSlot = FnToLPadSlotMap[F].second;
197       }
198 
199       if (!UnwindDest->getSinglePredecessor()) {
200         // The unwind destination doesn't have a single predecessor. Create an
201         // unwind destination which has only one predecessor.
202         BasicBlock *NewBB = BasicBlock::Create(Context, "new.lpad",
203                                                UnwindDest->getParent());
204         BranchInst::Create(UnwindDest, NewBB);
205         Invoke->setUnwindDest(NewBB);
206 
207         // Fix up any PHIs in the original unwind destination block.
208         for (BasicBlock::iterator
209                II = UnwindDest->begin(); isa<PHINode>(II); ++II) {
210           PHINode *PN = cast<PHINode>(II);
211           int Idx = PN->getBasicBlockIndex(Invoke->getParent());
212           if (Idx == -1) continue;
213           PN->setIncomingBlock(Idx, NewBB);
214         }
215 
216         UnwindDest = NewBB;
217       }
218 
219       IRBuilder<> Builder(Context);
220       Builder.SetInsertPoint(UnwindDest, UnwindDest->getFirstInsertionPt());
221 
222       Value *PersFn = Sel->getArgOperand(1);
223       LandingPadInst *LPI = Builder.CreateLandingPad(LPadSlotTy, PersFn, 0);
224       Value *LPExn = Builder.CreateExtractValue(LPI, 0);
225       Value *LPSel = Builder.CreateExtractValue(LPI, 1);
226       Builder.CreateStore(LPExn, ExnSlot);
227       Builder.CreateStore(LPSel, SelSlot);
228 
229       TransferClausesToLandingPadInst(LPI, Sel);
230 
231       DeadInsts.insert(Exn);
232       DeadInsts.insert(Sel);
233     }
234 
235     // Replace the old intrinsic calls with the values from the landingpad
236     // instruction(s). These values were stored in allocas for us to use here.
237     for (DenseMap<InvokeInst*, std::pair<Value*, Value*> >::iterator
238            I = InvokeToIntrinsicsMap.begin(), E = InvokeToIntrinsicsMap.end();
239          I != E; ++I) {
240       std::pair<Value*, Value*> EHIntrinsics = I->second;
241       CallInst *Exn = cast<CallInst>(EHIntrinsics.first);
242       CallInst *Sel = cast<CallInst>(EHIntrinsics.second);
243       BasicBlock *Parent = Exn->getParent();
244 
245       std::pair<Value*,Value*> ExnSelSlots = FnToLPadSlotMap[Parent->getParent()];
246 
247       IRBuilder<> Builder(Context);
248       Builder.SetInsertPoint(Parent, Exn);
249       LoadInst *LPExn = Builder.CreateLoad(ExnSelSlots.first, "exn.load");
250       LoadInst *LPSel = Builder.CreateLoad(ExnSelSlots.second, "sel.load");
251 
252       Exn->replaceAllUsesWith(LPExn);
253       Sel->replaceAllUsesWith(LPSel);
254     }
255 
256     // Remove the dead instructions.
257     for (SmallPtrSet<Instruction*, 32>::iterator
258            I = DeadInsts.begin(), E = DeadInsts.end(); I != E; ++I) {
259       Instruction *Inst = *I;
260       Inst->eraseFromParent();
261     }
262 
263     // Replace calls to "llvm.eh.resume" with the 'resume' instruction. Load the
264     // exception and selector values from the stored place.
265     Function *EHResume = M->getFunction("llvm.eh.resume");
266     if (!EHResume) return;
267 
268     while (!EHResume->use_empty()) {
269       CallInst *Resume = cast<CallInst>(EHResume->use_back());
270       BasicBlock *BB = Resume->getParent();
271 
272       IRBuilder<> Builder(Context);
273       Builder.SetInsertPoint(BB, Resume);
274 
275       Value *LPadVal =
276         Builder.CreateInsertValue(UndefValue::get(LPadSlotTy),
277                                   Resume->getArgOperand(0), 0, "lpad.val");
278       LPadVal = Builder.CreateInsertValue(LPadVal, Resume->getArgOperand(1),
279                                           1, "lpad.val");
280       Builder.CreateResume(LPadVal);
281 
282       // Remove all instructions after the 'resume.'
283       BasicBlock::iterator I = Resume;
284       while (I != BB->end()) {
285         Instruction *Inst = &*I++;
286         Inst->eraseFromParent();
287       }
288     }
289   }
290 
291 
292   /// This function strips all debug info intrinsics, except for llvm.dbg.declare.
293   /// If an llvm.dbg.declare intrinsic is invalid, then this function simply
294   /// strips that use.
CheckDebugInfoIntrinsics(Module * M)295   void CheckDebugInfoIntrinsics(Module *M) {
296     if (Function *FuncStart = M->getFunction("llvm.dbg.func.start")) {
297       while (!FuncStart->use_empty())
298         cast<CallInst>(FuncStart->use_back())->eraseFromParent();
299       FuncStart->eraseFromParent();
300     }
301 
302     if (Function *StopPoint = M->getFunction("llvm.dbg.stoppoint")) {
303       while (!StopPoint->use_empty())
304         cast<CallInst>(StopPoint->use_back())->eraseFromParent();
305       StopPoint->eraseFromParent();
306     }
307 
308     if (Function *RegionStart = M->getFunction("llvm.dbg.region.start")) {
309       while (!RegionStart->use_empty())
310         cast<CallInst>(RegionStart->use_back())->eraseFromParent();
311       RegionStart->eraseFromParent();
312     }
313 
314     if (Function *RegionEnd = M->getFunction("llvm.dbg.region.end")) {
315       while (!RegionEnd->use_empty())
316         cast<CallInst>(RegionEnd->use_back())->eraseFromParent();
317       RegionEnd->eraseFromParent();
318     }
319 
320     if (Function *Declare = M->getFunction("llvm.dbg.declare")) {
321       if (!Declare->use_empty()) {
322         DbgDeclareInst *DDI = cast<DbgDeclareInst>(Declare->use_back());
323         if (!isa<MDNode>(DDI->getArgOperand(0)) ||
324             !isa<MDNode>(DDI->getArgOperand(1))) {
325           while (!Declare->use_empty()) {
326             CallInst *CI = cast<CallInst>(Declare->use_back());
327             CI->eraseFromParent();
328           }
329           Declare->eraseFromParent();
330         }
331       }
332     }
333   }
334 } // end anonymous namespace
335 
FreeState()336 void BitcodeReader::FreeState() {
337   if (BufferOwned)
338     delete Buffer;
339   Buffer = 0;
340   std::vector<Type*>().swap(TypeList);
341   ValueList.clear();
342   MDValueList.clear();
343 
344   std::vector<AttributeSet>().swap(MAttributes);
345   std::vector<BasicBlock*>().swap(FunctionBBs);
346   std::vector<Function*>().swap(FunctionsWithBodies);
347   DeferredFunctionInfo.clear();
348   MDKindMap.clear();
349 }
350 
351 //===----------------------------------------------------------------------===//
352 //  Helper functions to implement forward reference resolution, etc.
353 //===----------------------------------------------------------------------===//
354 
355 /// ConvertToString - Convert a string from a record into an std::string, return
356 /// true on failure.
357 template<typename StrTy>
ConvertToString(SmallVector<uint64_t,64> & Record,unsigned Idx,StrTy & Result)358 static bool ConvertToString(SmallVector<uint64_t, 64> &Record, unsigned Idx,
359                             StrTy &Result) {
360   if (Idx > Record.size())
361     return true;
362 
363   for (unsigned i = Idx, e = Record.size(); i != e; ++i)
364     Result += (char)Record[i];
365   return false;
366 }
367 
GetDecodedLinkage(unsigned Val)368 static GlobalValue::LinkageTypes GetDecodedLinkage(unsigned Val) {
369   switch (Val) {
370   default: // Map unknown/new linkages to external
371   case 0:  return GlobalValue::ExternalLinkage;
372   case 1:  return GlobalValue::WeakAnyLinkage;
373   case 2:  return GlobalValue::AppendingLinkage;
374   case 3:  return GlobalValue::InternalLinkage;
375   case 4:  return GlobalValue::LinkOnceAnyLinkage;
376   case 5:  return GlobalValue::DLLImportLinkage;
377   case 6:  return GlobalValue::DLLExportLinkage;
378   case 7:  return GlobalValue::ExternalWeakLinkage;
379   case 8:  return GlobalValue::CommonLinkage;
380   case 9:  return GlobalValue::PrivateLinkage;
381   case 10: return GlobalValue::WeakODRLinkage;
382   case 11: return GlobalValue::LinkOnceODRLinkage;
383   case 12: return GlobalValue::AvailableExternallyLinkage;
384   case 13: return GlobalValue::LinkerPrivateLinkage;
385   case 14: return GlobalValue::LinkerPrivateWeakLinkage;
386   case 15: return GlobalValue::LinkOnceODRAutoHideLinkage;
387   }
388 }
389 
GetDecodedVisibility(unsigned Val)390 static GlobalValue::VisibilityTypes GetDecodedVisibility(unsigned Val) {
391   switch (Val) {
392   default: // Map unknown visibilities to default.
393   case 0: return GlobalValue::DefaultVisibility;
394   case 1: return GlobalValue::HiddenVisibility;
395   case 2: return GlobalValue::ProtectedVisibility;
396   }
397 }
398 
GetDecodedThreadLocalMode(unsigned Val)399 static GlobalVariable::ThreadLocalMode GetDecodedThreadLocalMode(unsigned Val) {
400   switch (Val) {
401     case 0: return GlobalVariable::NotThreadLocal;
402     default: // Map unknown non-zero value to general dynamic.
403     case 1: return GlobalVariable::GeneralDynamicTLSModel;
404     case 2: return GlobalVariable::LocalDynamicTLSModel;
405     case 3: return GlobalVariable::InitialExecTLSModel;
406     case 4: return GlobalVariable::LocalExecTLSModel;
407   }
408 }
409 
GetDecodedCastOpcode(unsigned Val)410 static int GetDecodedCastOpcode(unsigned Val) {
411   switch (Val) {
412   default: return -1;
413   case bitc::CAST_TRUNC   : return Instruction::Trunc;
414   case bitc::CAST_ZEXT    : return Instruction::ZExt;
415   case bitc::CAST_SEXT    : return Instruction::SExt;
416   case bitc::CAST_FPTOUI  : return Instruction::FPToUI;
417   case bitc::CAST_FPTOSI  : return Instruction::FPToSI;
418   case bitc::CAST_UITOFP  : return Instruction::UIToFP;
419   case bitc::CAST_SITOFP  : return Instruction::SIToFP;
420   case bitc::CAST_FPTRUNC : return Instruction::FPTrunc;
421   case bitc::CAST_FPEXT   : return Instruction::FPExt;
422   case bitc::CAST_PTRTOINT: return Instruction::PtrToInt;
423   case bitc::CAST_INTTOPTR: return Instruction::IntToPtr;
424   case bitc::CAST_BITCAST : return Instruction::BitCast;
425   }
426 }
GetDecodedBinaryOpcode(unsigned Val,Type * Ty)427 static int GetDecodedBinaryOpcode(unsigned Val, Type *Ty) {
428   switch (Val) {
429   default: return -1;
430   case bitc::BINOP_ADD:
431     return Ty->isFPOrFPVectorTy() ? Instruction::FAdd : Instruction::Add;
432   case bitc::BINOP_SUB:
433     return Ty->isFPOrFPVectorTy() ? Instruction::FSub : Instruction::Sub;
434   case bitc::BINOP_MUL:
435     return Ty->isFPOrFPVectorTy() ? Instruction::FMul : Instruction::Mul;
436   case bitc::BINOP_UDIV: return Instruction::UDiv;
437   case bitc::BINOP_SDIV:
438     return Ty->isFPOrFPVectorTy() ? Instruction::FDiv : Instruction::SDiv;
439   case bitc::BINOP_UREM: return Instruction::URem;
440   case bitc::BINOP_SREM:
441     return Ty->isFPOrFPVectorTy() ? Instruction::FRem : Instruction::SRem;
442   case bitc::BINOP_SHL:  return Instruction::Shl;
443   case bitc::BINOP_LSHR: return Instruction::LShr;
444   case bitc::BINOP_ASHR: return Instruction::AShr;
445   case bitc::BINOP_AND:  return Instruction::And;
446   case bitc::BINOP_OR:   return Instruction::Or;
447   case bitc::BINOP_XOR:  return Instruction::Xor;
448   }
449 }
450 
GetDecodedRMWOperation(unsigned Val)451 static AtomicRMWInst::BinOp GetDecodedRMWOperation(unsigned Val) {
452   switch (Val) {
453   default: return AtomicRMWInst::BAD_BINOP;
454   case bitc::RMW_XCHG: return AtomicRMWInst::Xchg;
455   case bitc::RMW_ADD: return AtomicRMWInst::Add;
456   case bitc::RMW_SUB: return AtomicRMWInst::Sub;
457   case bitc::RMW_AND: return AtomicRMWInst::And;
458   case bitc::RMW_NAND: return AtomicRMWInst::Nand;
459   case bitc::RMW_OR: return AtomicRMWInst::Or;
460   case bitc::RMW_XOR: return AtomicRMWInst::Xor;
461   case bitc::RMW_MAX: return AtomicRMWInst::Max;
462   case bitc::RMW_MIN: return AtomicRMWInst::Min;
463   case bitc::RMW_UMAX: return AtomicRMWInst::UMax;
464   case bitc::RMW_UMIN: return AtomicRMWInst::UMin;
465   }
466 }
467 
GetDecodedOrdering(unsigned Val)468 static AtomicOrdering GetDecodedOrdering(unsigned Val) {
469   switch (Val) {
470   case bitc::ORDERING_NOTATOMIC: return NotAtomic;
471   case bitc::ORDERING_UNORDERED: return Unordered;
472   case bitc::ORDERING_MONOTONIC: return Monotonic;
473   case bitc::ORDERING_ACQUIRE: return Acquire;
474   case bitc::ORDERING_RELEASE: return Release;
475   case bitc::ORDERING_ACQREL: return AcquireRelease;
476   default: // Map unknown orderings to sequentially-consistent.
477   case bitc::ORDERING_SEQCST: return SequentiallyConsistent;
478   }
479 }
480 
GetDecodedSynchScope(unsigned Val)481 static SynchronizationScope GetDecodedSynchScope(unsigned Val) {
482   switch (Val) {
483   case bitc::SYNCHSCOPE_SINGLETHREAD: return SingleThread;
484   default: // Map unknown scopes to cross-thread.
485   case bitc::SYNCHSCOPE_CROSSTHREAD: return CrossThread;
486   }
487 }
488 
489 namespace llvm {
490 namespace {
491   /// @brief A class for maintaining the slot number definition
492   /// as a placeholder for the actual definition for forward constants defs.
493   class ConstantPlaceHolder : public ConstantExpr {
494     void operator=(const ConstantPlaceHolder &); // DO NOT IMPLEMENT
495   public:
496     // allocate space for exactly one operand
operator new(size_t s)497     void *operator new(size_t s) {
498       return User::operator new(s, 1);
499     }
ConstantPlaceHolder(Type * Ty,LLVMContext & Context)500     explicit ConstantPlaceHolder(Type *Ty, LLVMContext& Context)
501       : ConstantExpr(Ty, Instruction::UserOp1, &Op<0>(), 1) {
502       Op<0>() = UndefValue::get(Type::getInt32Ty(Context));
503     }
504 
505     /// @brief Methods to support type inquiry through isa, cast, and dyn_cast.
506     //static inline bool classof(const ConstantPlaceHolder *) { return true; }
classof(const Value * V)507     static bool classof(const Value *V) {
508       return isa<ConstantExpr>(V) &&
509              cast<ConstantExpr>(V)->getOpcode() == Instruction::UserOp1;
510     }
511 
512 
513     /// Provide fast operand accessors
514     //DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
515   };
516 }
517 
518 // FIXME: can we inherit this from ConstantExpr?
519 template <>
520 struct OperandTraits<ConstantPlaceHolder> :
521   public FixedNumOperandTraits<ConstantPlaceHolder, 1> {
522 };
523 }
524 
525 
AssignValue(Value * V,unsigned Idx)526 void BitcodeReaderValueList::AssignValue(Value *V, unsigned Idx) {
527   if (Idx == size()) {
528     push_back(V);
529     return;
530   }
531 
532   if (Idx >= size())
533     resize(Idx+1);
534 
535   WeakVH &OldV = ValuePtrs[Idx];
536   if (OldV == 0) {
537     OldV = V;
538     return;
539   }
540 
541   // Handle constants and non-constants (e.g. instrs) differently for
542   // efficiency.
543   if (Constant *PHC = dyn_cast<Constant>(&*OldV)) {
544     ResolveConstants.push_back(std::make_pair(PHC, Idx));
545     OldV = V;
546   } else {
547     // If there was a forward reference to this value, replace it.
548     Value *PrevVal = OldV;
549     OldV->replaceAllUsesWith(V);
550     delete PrevVal;
551   }
552 }
553 
554 
getConstantFwdRef(unsigned Idx,Type * Ty)555 Constant *BitcodeReaderValueList::getConstantFwdRef(unsigned Idx,
556                                                     Type *Ty) {
557   if (Idx >= size())
558     resize(Idx + 1);
559 
560   if (Value *V = ValuePtrs[Idx]) {
561     assert(Ty == V->getType() && "Type mismatch in constant table!");
562     return cast<Constant>(V);
563   }
564 
565   // Create and return a placeholder, which will later be RAUW'd.
566   Constant *C = new ConstantPlaceHolder(Ty, Context);
567   ValuePtrs[Idx] = C;
568   return C;
569 }
570 
getValueFwdRef(unsigned Idx,Type * Ty)571 Value *BitcodeReaderValueList::getValueFwdRef(unsigned Idx, Type *Ty) {
572   if (Idx >= size())
573     resize(Idx + 1);
574 
575   if (Value *V = ValuePtrs[Idx]) {
576     assert((Ty == 0 || Ty == V->getType()) && "Type mismatch in value table!");
577     return V;
578   }
579 
580   // No type specified, must be invalid reference.
581   if (Ty == 0) return 0;
582 
583   // Create and return a placeholder, which will later be RAUW'd.
584   Value *V = new Argument(Ty);
585   ValuePtrs[Idx] = V;
586   return V;
587 }
588 
589 /// ResolveConstantForwardRefs - Once all constants are read, this method bulk
590 /// resolves any forward references.  The idea behind this is that we sometimes
591 /// get constants (such as large arrays) which reference *many* forward ref
592 /// constants.  Replacing each of these causes a lot of thrashing when
593 /// building/reuniquing the constant.  Instead of doing this, we look at all the
594 /// uses and rewrite all the place holders at once for any constant that uses
595 /// a placeholder.
ResolveConstantForwardRefs()596 void BitcodeReaderValueList::ResolveConstantForwardRefs() {
597   // Sort the values by-pointer so that they are efficient to look up with a
598   // binary search.
599   std::sort(ResolveConstants.begin(), ResolveConstants.end());
600 
601   SmallVector<Constant*, 64> NewOps;
602 
603   while (!ResolveConstants.empty()) {
604     Value *RealVal = operator[](ResolveConstants.back().second);
605     Constant *Placeholder = ResolveConstants.back().first;
606     ResolveConstants.pop_back();
607 
608     // Loop over all users of the placeholder, updating them to reference the
609     // new value.  If they reference more than one placeholder, update them all
610     // at once.
611     while (!Placeholder->use_empty()) {
612       Value::use_iterator UI = Placeholder->use_begin();
613       User *U = *UI;
614 
615       // If the using object isn't uniqued, just update the operands.  This
616       // handles instructions and initializers for global variables.
617       if (!isa<Constant>(U) || isa<GlobalValue>(U)) {
618         UI.getUse().set(RealVal);
619         continue;
620       }
621 
622       // Otherwise, we have a constant that uses the placeholder.  Replace that
623       // constant with a new constant that has *all* placeholder uses updated.
624       Constant *UserC = cast<Constant>(U);
625       for (User::op_iterator I = UserC->op_begin(), E = UserC->op_end();
626            I != E; ++I) {
627         Value *NewOp;
628         if (!isa<ConstantPlaceHolder>(*I)) {
629           // Not a placeholder reference.
630           NewOp = *I;
631         } else if (*I == Placeholder) {
632           // Common case is that it just references this one placeholder.
633           NewOp = RealVal;
634         } else {
635           // Otherwise, look up the placeholder in ResolveConstants.
636           ResolveConstantsTy::iterator It =
637             std::lower_bound(ResolveConstants.begin(), ResolveConstants.end(),
638                              std::pair<Constant*, unsigned>(cast<Constant>(*I),
639                                                             0));
640           assert(It != ResolveConstants.end() && It->first == *I);
641           NewOp = operator[](It->second);
642         }
643 
644         NewOps.push_back(cast<Constant>(NewOp));
645       }
646 
647       // Make the new constant.
648       Constant *NewC;
649       if (ConstantArray *UserCA = dyn_cast<ConstantArray>(UserC)) {
650         NewC = ConstantArray::get(UserCA->getType(), NewOps);
651       } else if (ConstantStruct *UserCS = dyn_cast<ConstantStruct>(UserC)) {
652         NewC = ConstantStruct::get(UserCS->getType(), NewOps);
653       } else if (isa<ConstantVector>(UserC)) {
654         NewC = ConstantVector::get(NewOps);
655       } else {
656         assert(isa<ConstantExpr>(UserC) && "Must be a ConstantExpr.");
657         NewC = cast<ConstantExpr>(UserC)->getWithOperands(NewOps);
658       }
659 
660       UserC->replaceAllUsesWith(NewC);
661       UserC->destroyConstant();
662       NewOps.clear();
663     }
664 
665     // Update all ValueHandles, they should be the only users at this point.
666     Placeholder->replaceAllUsesWith(RealVal);
667     delete Placeholder;
668   }
669 }
670 
AssignValue(Value * V,unsigned Idx)671 void BitcodeReaderMDValueList::AssignValue(Value *V, unsigned Idx) {
672   if (Idx == size()) {
673     push_back(V);
674     return;
675   }
676 
677   if (Idx >= size())
678     resize(Idx+1);
679 
680   WeakVH &OldV = MDValuePtrs[Idx];
681   if (OldV == 0) {
682     OldV = V;
683     return;
684   }
685 
686   // If there was a forward reference to this value, replace it.
687   MDNode *PrevVal = cast<MDNode>(OldV);
688   OldV->replaceAllUsesWith(V);
689   MDNode::deleteTemporary(PrevVal);
690   // Deleting PrevVal sets Idx value in MDValuePtrs to null. Set new
691   // value for Idx.
692   MDValuePtrs[Idx] = V;
693 }
694 
getValueFwdRef(unsigned Idx)695 Value *BitcodeReaderMDValueList::getValueFwdRef(unsigned Idx) {
696   if (Idx >= size())
697     resize(Idx + 1);
698 
699   if (Value *V = MDValuePtrs[Idx]) {
700     assert(V->getType()->isMetadataTy() && "Type mismatch in value table!");
701     return V;
702   }
703 
704   // Create and return a placeholder, which will later be RAUW'd.
705   Value *V = MDNode::getTemporary(Context, ArrayRef<Value*>());
706   MDValuePtrs[Idx] = V;
707   return V;
708 }
709 
getTypeByID(unsigned ID)710 Type *BitcodeReader::getTypeByID(unsigned ID) {
711   // The type table size is always specified correctly.
712   if (ID >= TypeList.size())
713     return 0;
714 
715   if (Type *Ty = TypeList[ID])
716     return Ty;
717 
718   // If we have a forward reference, the only possible case is when it is to a
719   // named struct.  Just create a placeholder for now.
720   return TypeList[ID] = StructType::create(Context);
721 }
722 
723 /// FIXME: Remove in LLVM 3.1, only used by ParseOldTypeTable.
getTypeByIDOrNull(unsigned ID)724 Type *BitcodeReader::getTypeByIDOrNull(unsigned ID) {
725   if (ID >= TypeList.size())
726     TypeList.resize(ID+1);
727 
728   return TypeList[ID];
729 }
730 
731 
732 //===----------------------------------------------------------------------===//
733 //  Functions for parsing blocks from the bitcode file
734 //===----------------------------------------------------------------------===//
735 
736 
737 /// \brief This fills an AttrBuilder object with the LLVM attributes that have
738 /// been decoded from the given integer. This function must stay in sync with
739 /// 'encodeLLVMAttributesForBitcode'.
decodeLLVMAttributesForBitcode(AttrBuilder & B,uint64_t EncodedAttrs)740 static void decodeLLVMAttributesForBitcode(AttrBuilder &B,
741                                            uint64_t EncodedAttrs) {
742   // FIXME: Remove in 4.0.
743 
744   // The alignment is stored as a 16-bit raw value from bits 31--16.  We shift
745   // the bits above 31 down by 11 bits.
746   unsigned Alignment = (EncodedAttrs & (0xffffULL << 16)) >> 16;
747   assert((!Alignment || isPowerOf2_32(Alignment)) &&
748          "Alignment must be a power of two.");
749 
750   if (Alignment)
751     B.addAlignmentAttr(Alignment);
752   B.addRawValue(((EncodedAttrs & (0xfffffULL << 32)) >> 11) |
753                 (EncodedAttrs & 0xffff));
754 }
755 
ParseAttributeBlock()756 bool BitcodeReader::ParseAttributeBlock() {
757   if (Stream.EnterSubBlock(bitc::PARAMATTR_BLOCK_ID))
758     return Error("Malformed block record");
759 
760   if (!MAttributes.empty())
761     return Error("Multiple PARAMATTR blocks found!");
762 
763   SmallVector<uint64_t, 64> Record;
764 
765   SmallVector<AttributeSet, 8> Attrs;
766 
767   // Read all the records.
768   while (1) {
769     BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
770 
771     switch (Entry.Kind) {
772     case BitstreamEntry::SubBlock: // Handled for us already.
773     case BitstreamEntry::Error:
774       return Error("Error at end of PARAMATTR block");
775     case BitstreamEntry::EndBlock:
776       return false;
777     case BitstreamEntry::Record:
778       // The interesting case.
779       break;
780     }
781 
782     // Read a record.
783     Record.clear();
784     switch (Stream.readRecord(Entry.ID, Record)) {
785     default:  // Default behavior: ignore.
786       break;
787     case bitc::PARAMATTR_CODE_ENTRY_OLD: { // ENTRY: [paramidx0, attr0, ...]
788       // FIXME: Remove in 4.0.
789       if (Record.size() & 1)
790         return Error("Invalid ENTRY record");
791 
792       for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
793         AttrBuilder B;
794         decodeLLVMAttributesForBitcode(B, Record[i+1]);
795         Attrs.push_back(AttributeSet::get(Context, Record[i], B));
796       }
797 
798       MAttributes.push_back(AttributeSet::get(Context, Attrs));
799       Attrs.clear();
800       break;
801     }
802     case bitc::PARAMATTR_CODE_ENTRY: { // ENTRY: [attrgrp0, attrgrp1, ...]
803       for (unsigned i = 0, e = Record.size(); i != e; ++i)
804         Attrs.push_back(MAttributeGroups[Record[i]]);
805 
806       MAttributes.push_back(AttributeSet::get(Context, Attrs));
807       Attrs.clear();
808       break;
809     }
810     }
811   }
812 }
813 
814 
ParseTypeTable()815 bool BitcodeReader::ParseTypeTable() {
816   if (Stream.EnterSubBlock(bitc::TYPE_BLOCK_ID_NEW))
817     return Error("Malformed block record");
818 
819   return ParseTypeTableBody();
820 }
821 
ParseTypeTableBody()822 bool BitcodeReader::ParseTypeTableBody() {
823   if (!TypeList.empty())
824     return Error("Multiple TYPE_BLOCKs found!");
825 
826   SmallVector<uint64_t, 64> Record;
827   unsigned NumRecords = 0;
828 
829   SmallString<64> TypeName;
830 
831   // Read all the records for this type table.
832   while (1) {
833     BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
834 
835     switch (Entry.Kind) {
836     case BitstreamEntry::SubBlock: // Handled for us already.
837     case BitstreamEntry::Error:
838       Error("Error in the type table block");
839       return true;
840     case BitstreamEntry::EndBlock:
841       if (NumRecords != TypeList.size())
842         return Error("Invalid type forward reference in TYPE_BLOCK");
843       return false;
844     case BitstreamEntry::Record:
845       // The interesting case.
846       break;
847     }
848 
849     // Read a record.
850     Record.clear();
851     Type *ResultTy = 0;
852     switch (Stream.readRecord(Entry.ID, Record)) {
853     default: return Error("unknown type in type table");
854     case bitc::TYPE_CODE_NUMENTRY: // TYPE_CODE_NUMENTRY: [numentries]
855       // TYPE_CODE_NUMENTRY contains a count of the number of types in the
856       // type list.  This allows us to reserve space.
857       if (Record.size() < 1)
858         return Error("Invalid TYPE_CODE_NUMENTRY record");
859       TypeList.resize(Record[0]);
860       continue;
861     case bitc::TYPE_CODE_VOID:      // VOID
862       ResultTy = Type::getVoidTy(Context);
863       break;
864     case bitc::TYPE_CODE_HALF:     // HALF
865       ResultTy = Type::getHalfTy(Context);
866       break;
867     case bitc::TYPE_CODE_FLOAT:     // FLOAT
868       ResultTy = Type::getFloatTy(Context);
869       break;
870     case bitc::TYPE_CODE_DOUBLE:    // DOUBLE
871       ResultTy = Type::getDoubleTy(Context);
872       break;
873     case bitc::TYPE_CODE_X86_FP80:  // X86_FP80
874       ResultTy = Type::getX86_FP80Ty(Context);
875       break;
876     case bitc::TYPE_CODE_FP128:     // FP128
877       ResultTy = Type::getFP128Ty(Context);
878       break;
879     case bitc::TYPE_CODE_PPC_FP128: // PPC_FP128
880       ResultTy = Type::getPPC_FP128Ty(Context);
881       break;
882     case bitc::TYPE_CODE_LABEL:     // LABEL
883       ResultTy = Type::getLabelTy(Context);
884       break;
885     case bitc::TYPE_CODE_METADATA:  // METADATA
886       ResultTy = Type::getMetadataTy(Context);
887       break;
888     case bitc::TYPE_CODE_X86_MMX:   // X86_MMX
889       ResultTy = Type::getX86_MMXTy(Context);
890       break;
891     case bitc::TYPE_CODE_INTEGER:   // INTEGER: [width]
892       if (Record.size() < 1)
893         return Error("Invalid Integer type record");
894 
895       ResultTy = IntegerType::get(Context, Record[0]);
896       break;
897     case bitc::TYPE_CODE_POINTER: { // POINTER: [pointee type] or
898                                     //          [pointee type, address space]
899       if (Record.size() < 1)
900         return Error("Invalid POINTER type record");
901       unsigned AddressSpace = 0;
902       if (Record.size() == 2)
903         AddressSpace = Record[1];
904       ResultTy = getTypeByID(Record[0]);
905       if (ResultTy == 0) return Error("invalid element type in pointer type");
906       ResultTy = PointerType::get(ResultTy, AddressSpace);
907       break;
908     }
909     case bitc::TYPE_CODE_FUNCTION_OLD: {
910       // FIXME: attrid is dead, remove it in LLVM 4.0
911       // FUNCTION: [vararg, attrid, retty, paramty x N]
912       if (Record.size() < 3)
913         return Error("Invalid FUNCTION type record");
914       SmallVector<Type*, 8> ArgTys;
915       for (unsigned i = 3, e = Record.size(); i != e; ++i) {
916         if (Type *T = getTypeByID(Record[i]))
917           ArgTys.push_back(T);
918         else
919           break;
920       }
921 
922       ResultTy = getTypeByID(Record[2]);
923       if (ResultTy == 0 || ArgTys.size() < Record.size()-3)
924         return Error("invalid type in function type");
925 
926       ResultTy = FunctionType::get(ResultTy, ArgTys, Record[0]);
927       break;
928     }
929     case bitc::TYPE_CODE_FUNCTION: {
930       // FUNCTION: [vararg, retty, paramty x N]
931       if (Record.size() < 2)
932         return Error("Invalid FUNCTION type record");
933       SmallVector<Type*, 8> ArgTys;
934       for (unsigned i = 2, e = Record.size(); i != e; ++i) {
935         if (Type *T = getTypeByID(Record[i]))
936           ArgTys.push_back(T);
937         else
938           break;
939       }
940 
941       ResultTy = getTypeByID(Record[1]);
942       if (ResultTy == 0 || ArgTys.size() < Record.size()-2)
943         return Error("invalid type in function type");
944 
945       ResultTy = FunctionType::get(ResultTy, ArgTys, Record[0]);
946       break;
947     }
948     case bitc::TYPE_CODE_STRUCT_ANON: {  // STRUCT: [ispacked, eltty x N]
949       if (Record.size() < 1)
950         return Error("Invalid STRUCT type record");
951       SmallVector<Type*, 8> EltTys;
952       for (unsigned i = 1, e = Record.size(); i != e; ++i) {
953         if (Type *T = getTypeByID(Record[i]))
954           EltTys.push_back(T);
955         else
956           break;
957       }
958       if (EltTys.size() != Record.size()-1)
959         return Error("invalid type in struct type");
960       ResultTy = StructType::get(Context, EltTys, Record[0]);
961       break;
962     }
963     case bitc::TYPE_CODE_STRUCT_NAME:   // STRUCT_NAME: [strchr x N]
964       if (ConvertToString(Record, 0, TypeName))
965         return Error("Invalid STRUCT_NAME record");
966       continue;
967 
968     case bitc::TYPE_CODE_STRUCT_NAMED: { // STRUCT: [ispacked, eltty x N]
969       if (Record.size() < 1)
970         return Error("Invalid STRUCT type record");
971 
972       if (NumRecords >= TypeList.size())
973         return Error("invalid TYPE table");
974 
975       // Check to see if this was forward referenced, if so fill in the temp.
976       StructType *Res = cast_or_null<StructType>(TypeList[NumRecords]);
977       if (Res) {
978         Res->setName(TypeName);
979         TypeList[NumRecords] = 0;
980       } else  // Otherwise, create a new struct.
981         Res = StructType::create(Context, TypeName);
982       TypeName.clear();
983 
984       SmallVector<Type*, 8> EltTys;
985       for (unsigned i = 1, e = Record.size(); i != e; ++i) {
986         if (Type *T = getTypeByID(Record[i]))
987           EltTys.push_back(T);
988         else
989           break;
990       }
991       if (EltTys.size() != Record.size()-1)
992         return Error("invalid STRUCT type record");
993       Res->setBody(EltTys, Record[0]);
994       ResultTy = Res;
995       break;
996     }
997     case bitc::TYPE_CODE_OPAQUE: {       // OPAQUE: []
998       if (Record.size() != 1)
999         return Error("Invalid OPAQUE type record");
1000 
1001       if (NumRecords >= TypeList.size())
1002         return Error("invalid TYPE table");
1003 
1004       // Check to see if this was forward referenced, if so fill in the temp.
1005       StructType *Res = cast_or_null<StructType>(TypeList[NumRecords]);
1006       if (Res) {
1007         Res->setName(TypeName);
1008         TypeList[NumRecords] = 0;
1009       } else  // Otherwise, create a new struct with no body.
1010         Res = StructType::create(Context, TypeName);
1011       TypeName.clear();
1012       ResultTy = Res;
1013       break;
1014     }
1015     case bitc::TYPE_CODE_ARRAY:     // ARRAY: [numelts, eltty]
1016       if (Record.size() < 2)
1017         return Error("Invalid ARRAY type record");
1018       if ((ResultTy = getTypeByID(Record[1])))
1019         ResultTy = ArrayType::get(ResultTy, Record[0]);
1020       else
1021         return Error("Invalid ARRAY type element");
1022       break;
1023     case bitc::TYPE_CODE_VECTOR:    // VECTOR: [numelts, eltty]
1024       if (Record.size() < 2)
1025         return Error("Invalid VECTOR type record");
1026       if ((ResultTy = getTypeByID(Record[1])))
1027         ResultTy = VectorType::get(ResultTy, Record[0]);
1028       else
1029         return Error("Invalid ARRAY type element");
1030       break;
1031     }
1032 
1033     if (NumRecords >= TypeList.size())
1034       return Error("invalid TYPE table");
1035     assert(ResultTy && "Didn't read a type?");
1036     assert(TypeList[NumRecords] == 0 && "Already read type?");
1037     TypeList[NumRecords++] = ResultTy;
1038   }
1039 }
1040 
1041 // FIXME: Remove in LLVM 3.1
ParseOldTypeTable()1042 bool BitcodeReader::ParseOldTypeTable() {
1043   if (Stream.EnterSubBlock(TYPE_BLOCK_ID_OLD_3_0))
1044     return Error("Malformed block record");
1045 
1046   if (!TypeList.empty())
1047     return Error("Multiple TYPE_BLOCKs found!");
1048 
1049 
1050   // While horrible, we have no good ordering of types in the bc file.  Just
1051   // iteratively parse types out of the bc file in multiple passes until we get
1052   // them all.  Do this by saving a cursor for the start of the type block.
1053   BitstreamCursor StartOfTypeBlockCursor(Stream);
1054 
1055   unsigned NumTypesRead = 0;
1056 
1057   SmallVector<uint64_t, 64> Record;
1058 RestartScan:
1059   unsigned NextTypeID = 0;
1060   bool ReadAnyTypes = false;
1061 
1062   // Read all the records for this type table.
1063   while (1) {
1064     unsigned Code = Stream.ReadCode();
1065     if (Code == bitc::END_BLOCK) {
1066       if (NextTypeID != TypeList.size())
1067         return Error("Invalid type forward reference in TYPE_BLOCK_ID_OLD");
1068 
1069       // If we haven't read all of the types yet, iterate again.
1070       if (NumTypesRead != TypeList.size()) {
1071         // If we didn't successfully read any types in this pass, then we must
1072         // have an unhandled forward reference.
1073         if (!ReadAnyTypes)
1074           return Error("Obsolete bitcode contains unhandled recursive type");
1075 
1076         Stream = StartOfTypeBlockCursor;
1077         goto RestartScan;
1078       }
1079 
1080       if (Stream.ReadBlockEnd())
1081         return Error("Error at end of type table block");
1082       return false;
1083     }
1084 
1085     if (Code == bitc::ENTER_SUBBLOCK) {
1086       // No known subblocks, always skip them.
1087       Stream.ReadSubBlockID();
1088       if (Stream.SkipBlock())
1089         return Error("Malformed block record");
1090       continue;
1091     }
1092 
1093     if (Code == bitc::DEFINE_ABBREV) {
1094       Stream.ReadAbbrevRecord();
1095       continue;
1096     }
1097 
1098     // Read a record.
1099     Record.clear();
1100     Type *ResultTy = 0;
1101     switch (Stream.readRecord(Code, Record)) {
1102     default: return Error("unknown type in type table");
1103     case bitc::TYPE_CODE_NUMENTRY: // TYPE_CODE_NUMENTRY: [numentries]
1104       // TYPE_CODE_NUMENTRY contains a count of the number of types in the
1105       // type list.  This allows us to reserve space.
1106       if (Record.size() < 1)
1107         return Error("Invalid TYPE_CODE_NUMENTRY record");
1108       TypeList.resize(Record[0]);
1109       continue;
1110     case bitc::TYPE_CODE_VOID:      // VOID
1111       ResultTy = Type::getVoidTy(Context);
1112       break;
1113     case bitc::TYPE_CODE_FLOAT:     // FLOAT
1114       ResultTy = Type::getFloatTy(Context);
1115       break;
1116     case bitc::TYPE_CODE_DOUBLE:    // DOUBLE
1117       ResultTy = Type::getDoubleTy(Context);
1118       break;
1119     case bitc::TYPE_CODE_X86_FP80:  // X86_FP80
1120       ResultTy = Type::getX86_FP80Ty(Context);
1121       break;
1122     case bitc::TYPE_CODE_FP128:     // FP128
1123       ResultTy = Type::getFP128Ty(Context);
1124       break;
1125     case bitc::TYPE_CODE_PPC_FP128: // PPC_FP128
1126       ResultTy = Type::getPPC_FP128Ty(Context);
1127       break;
1128     case bitc::TYPE_CODE_LABEL:     // LABEL
1129       ResultTy = Type::getLabelTy(Context);
1130       break;
1131     case bitc::TYPE_CODE_METADATA:  // METADATA
1132       ResultTy = Type::getMetadataTy(Context);
1133       break;
1134     case bitc::TYPE_CODE_X86_MMX:   // X86_MMX
1135       ResultTy = Type::getX86_MMXTy(Context);
1136       break;
1137     case bitc::TYPE_CODE_INTEGER:   // INTEGER: [width]
1138       if (Record.size() < 1)
1139         return Error("Invalid Integer type record");
1140       ResultTy = IntegerType::get(Context, Record[0]);
1141       break;
1142     case bitc::TYPE_CODE_OPAQUE:    // OPAQUE
1143       if (NextTypeID < TypeList.size() && TypeList[NextTypeID] == 0)
1144         ResultTy = StructType::create(Context, "");
1145       break;
1146     case TYPE_CODE_STRUCT_OLD_3_0: {// STRUCT_OLD
1147       if (NextTypeID >= TypeList.size()) break;
1148       // If we already read it, don't reprocess.
1149       if (TypeList[NextTypeID] &&
1150           !cast<StructType>(TypeList[NextTypeID])->isOpaque())
1151         break;
1152 
1153       // Set a type.
1154       if (TypeList[NextTypeID] == 0)
1155         TypeList[NextTypeID] = StructType::create(Context, "");
1156 
1157       std::vector<Type*> EltTys;
1158       for (unsigned i = 1, e = Record.size(); i != e; ++i) {
1159         if (Type *Elt = getTypeByIDOrNull(Record[i]))
1160           EltTys.push_back(Elt);
1161         else
1162           break;
1163       }
1164 
1165       if (EltTys.size() != Record.size()-1)
1166         break;      // Not all elements are ready.
1167 
1168       cast<StructType>(TypeList[NextTypeID])->setBody(EltTys, Record[0]);
1169       ResultTy = TypeList[NextTypeID];
1170       TypeList[NextTypeID] = 0;
1171       break;
1172     }
1173     case bitc::TYPE_CODE_POINTER: { // POINTER: [pointee type] or
1174       //          [pointee type, address space]
1175       if (Record.size() < 1)
1176         return Error("Invalid POINTER type record");
1177       unsigned AddressSpace = 0;
1178       if (Record.size() == 2)
1179         AddressSpace = Record[1];
1180       if ((ResultTy = getTypeByIDOrNull(Record[0])))
1181         ResultTy = PointerType::get(ResultTy, AddressSpace);
1182       break;
1183     }
1184     case bitc::TYPE_CODE_FUNCTION_OLD: {
1185       // FIXME: attrid is dead, remove it in LLVM 3.0
1186       // FUNCTION: [vararg, attrid, retty, paramty x N]
1187       if (Record.size() < 3)
1188         return Error("Invalid FUNCTION type record");
1189       std::vector<Type*> ArgTys;
1190       for (unsigned i = 3, e = Record.size(); i != e; ++i) {
1191         if (Type *Elt = getTypeByIDOrNull(Record[i]))
1192           ArgTys.push_back(Elt);
1193         else
1194           break;
1195       }
1196       if (ArgTys.size()+3 != Record.size())
1197         break;  // Something was null.
1198       if ((ResultTy = getTypeByIDOrNull(Record[2])))
1199         ResultTy = FunctionType::get(ResultTy, ArgTys, Record[0]);
1200       break;
1201     }
1202     case bitc::TYPE_CODE_FUNCTION: {
1203       // FUNCTION: [vararg, retty, paramty x N]
1204       if (Record.size() < 2)
1205         return Error("Invalid FUNCTION type record");
1206       std::vector<Type*> ArgTys;
1207       for (unsigned i = 2, e = Record.size(); i != e; ++i) {
1208         if (Type *Elt = getTypeByIDOrNull(Record[i]))
1209           ArgTys.push_back(Elt);
1210         else
1211           break;
1212       }
1213       if (ArgTys.size()+2 != Record.size())
1214         break;  // Something was null.
1215       if ((ResultTy = getTypeByIDOrNull(Record[1])))
1216         ResultTy = FunctionType::get(ResultTy, ArgTys, Record[0]);
1217       break;
1218     }
1219     case bitc::TYPE_CODE_ARRAY:     // ARRAY: [numelts, eltty]
1220       if (Record.size() < 2)
1221         return Error("Invalid ARRAY type record");
1222       if ((ResultTy = getTypeByIDOrNull(Record[1])))
1223         ResultTy = ArrayType::get(ResultTy, Record[0]);
1224       break;
1225     case bitc::TYPE_CODE_VECTOR:    // VECTOR: [numelts, eltty]
1226       if (Record.size() < 2)
1227         return Error("Invalid VECTOR type record");
1228       if ((ResultTy = getTypeByIDOrNull(Record[1])))
1229         ResultTy = VectorType::get(ResultTy, Record[0]);
1230       break;
1231     }
1232 
1233     if (NextTypeID >= TypeList.size())
1234       return Error("invalid TYPE table");
1235 
1236     if (ResultTy && TypeList[NextTypeID] == 0) {
1237       ++NumTypesRead;
1238       ReadAnyTypes = true;
1239 
1240       TypeList[NextTypeID] = ResultTy;
1241     }
1242 
1243     ++NextTypeID;
1244   }
1245 }
1246 
1247 
ParseOldTypeSymbolTable()1248 bool BitcodeReader::ParseOldTypeSymbolTable() {
1249   if (Stream.EnterSubBlock(TYPE_SYMTAB_BLOCK_ID_OLD_3_0))
1250     return Error("Malformed block record");
1251 
1252   SmallVector<uint64_t, 64> Record;
1253 
1254   // Read all the records for this type table.
1255   std::string TypeName;
1256   while (1) {
1257     unsigned Code = Stream.ReadCode();
1258     if (Code == bitc::END_BLOCK) {
1259       if (Stream.ReadBlockEnd())
1260         return Error("Error at end of type symbol table block");
1261       return false;
1262     }
1263 
1264     if (Code == bitc::ENTER_SUBBLOCK) {
1265       // No known subblocks, always skip them.
1266       Stream.ReadSubBlockID();
1267       if (Stream.SkipBlock())
1268         return Error("Malformed block record");
1269       continue;
1270     }
1271 
1272     if (Code == bitc::DEFINE_ABBREV) {
1273       Stream.ReadAbbrevRecord();
1274       continue;
1275     }
1276 
1277     // Read a record.
1278     Record.clear();
1279     switch (Stream.readRecord(Code, Record)) {
1280     default:  // Default behavior: unknown type.
1281       break;
1282     case bitc::TST_CODE_ENTRY:    // TST_ENTRY: [typeid, namechar x N]
1283       if (ConvertToString(Record, 1, TypeName))
1284         return Error("Invalid TST_ENTRY record");
1285       unsigned TypeID = Record[0];
1286       if (TypeID >= TypeList.size())
1287         return Error("Invalid Type ID in TST_ENTRY record");
1288 
1289       // Only apply the type name to a struct type with no name.
1290       if (StructType *STy = dyn_cast<StructType>(TypeList[TypeID]))
1291         if (!STy->isLiteral() && !STy->hasName())
1292           STy->setName(TypeName);
1293       TypeName.clear();
1294       break;
1295     }
1296   }
1297 }
1298 
ParseValueSymbolTable()1299 bool BitcodeReader::ParseValueSymbolTable() {
1300   if (Stream.EnterSubBlock(bitc::VALUE_SYMTAB_BLOCK_ID))
1301     return Error("Malformed block record");
1302 
1303   SmallVector<uint64_t, 64> Record;
1304 
1305   // Read all the records for this value table.
1306   SmallString<128> ValueName;
1307   while (1) {
1308     unsigned Code = Stream.ReadCode();
1309     if (Code == bitc::END_BLOCK) {
1310       if (Stream.ReadBlockEnd())
1311         return Error("Error at end of value symbol table block");
1312       return false;
1313     }
1314     if (Code == bitc::ENTER_SUBBLOCK) {
1315       // No known subblocks, always skip them.
1316       Stream.ReadSubBlockID();
1317       if (Stream.SkipBlock())
1318         return Error("Malformed block record");
1319       continue;
1320     }
1321 
1322     if (Code == bitc::DEFINE_ABBREV) {
1323       Stream.ReadAbbrevRecord();
1324       continue;
1325     }
1326 
1327     // Read a record.
1328     Record.clear();
1329     switch (Stream.readRecord(Code, Record)) {
1330     default:  // Default behavior: unknown type.
1331       break;
1332     case bitc::VST_CODE_ENTRY: {  // VST_ENTRY: [valueid, namechar x N]
1333       if (ConvertToString(Record, 1, ValueName))
1334         return Error("Invalid VST_ENTRY record");
1335       unsigned ValueID = Record[0];
1336       if (ValueID >= ValueList.size())
1337         return Error("Invalid Value ID in VST_ENTRY record");
1338       Value *V = ValueList[ValueID];
1339 
1340       V->setName(StringRef(ValueName.data(), ValueName.size()));
1341       ValueName.clear();
1342       break;
1343     }
1344     case bitc::VST_CODE_BBENTRY: {
1345       if (ConvertToString(Record, 1, ValueName))
1346         return Error("Invalid VST_BBENTRY record");
1347       BasicBlock *BB = getBasicBlock(Record[0]);
1348       if (BB == 0)
1349         return Error("Invalid BB ID in VST_BBENTRY record");
1350 
1351       BB->setName(StringRef(ValueName.data(), ValueName.size()));
1352       ValueName.clear();
1353       break;
1354     }
1355     }
1356   }
1357 }
1358 
ParseMetadata()1359 bool BitcodeReader::ParseMetadata() {
1360   unsigned NextMDValueNo = MDValueList.size();
1361 
1362   if (Stream.EnterSubBlock(bitc::METADATA_BLOCK_ID))
1363     return Error("Malformed block record");
1364 
1365   SmallVector<uint64_t, 64> Record;
1366 
1367   // Read all the records.
1368   while (1) {
1369     unsigned Code = Stream.ReadCode();
1370     if (Code == bitc::END_BLOCK) {
1371       if (Stream.ReadBlockEnd())
1372         return Error("Error at end of PARAMATTR block");
1373       return false;
1374     }
1375 
1376     if (Code == bitc::ENTER_SUBBLOCK) {
1377       // No known subblocks, always skip them.
1378       Stream.ReadSubBlockID();
1379       if (Stream.SkipBlock())
1380         return Error("Malformed block record");
1381       continue;
1382     }
1383 
1384     if (Code == bitc::DEFINE_ABBREV) {
1385       Stream.ReadAbbrevRecord();
1386       continue;
1387     }
1388 
1389     bool IsFunctionLocal = false;
1390     // Read a record.
1391     Record.clear();
1392     Code = Stream.readRecord(Code, Record);
1393     switch (Code) {
1394     default:  // Default behavior: ignore.
1395       break;
1396     case bitc::METADATA_NAME: {
1397       // Read named of the named metadata.
1398       unsigned NameLength = Record.size();
1399       SmallString<8> Name;
1400       Name.resize(NameLength);
1401       for (unsigned i = 0; i != NameLength; ++i)
1402         Name[i] = Record[i];
1403       Record.clear();
1404       Code = Stream.ReadCode();
1405 
1406       // METADATA_NAME is always followed by METADATA_NAMED_NODE.
1407       unsigned NextBitCode = Stream.readRecord(Code, Record);
1408       assert(NextBitCode == bitc::METADATA_NAMED_NODE); (void)NextBitCode;
1409 
1410       // Read named metadata elements.
1411       unsigned Size = Record.size();
1412       NamedMDNode *NMD = TheModule->getOrInsertNamedMetadata(Name);
1413       for (unsigned i = 0; i != Size; ++i) {
1414         MDNode *MD = dyn_cast<MDNode>(MDValueList.getValueFwdRef(Record[i]));
1415         if (MD == 0)
1416           return Error("Malformed metadata record");
1417         NMD->addOperand(MD);
1418       }
1419       break;
1420     }
1421     case bitc::METADATA_FN_NODE:
1422       IsFunctionLocal = true;
1423       // fall-through
1424     case bitc::METADATA_NODE: {
1425       if (Record.size() % 2 == 1)
1426         return Error("Invalid METADATA_NODE record");
1427 
1428       unsigned Size = Record.size();
1429       SmallVector<Value*, 8> Elts;
1430       for (unsigned i = 0; i != Size; i += 2) {
1431         Type *Ty = getTypeByID(Record[i]);
1432         if (!Ty) return Error("Invalid METADATA_NODE record");
1433         if (Ty->isMetadataTy())
1434           Elts.push_back(MDValueList.getValueFwdRef(Record[i+1]));
1435         else if (!Ty->isVoidTy())
1436           Elts.push_back(ValueList.getValueFwdRef(Record[i+1], Ty));
1437         else
1438           Elts.push_back(NULL);
1439       }
1440       Value *V = MDNode::getWhenValsUnresolved(Context, Elts, IsFunctionLocal);
1441       IsFunctionLocal = false;
1442       MDValueList.AssignValue(V, NextMDValueNo++);
1443       break;
1444     }
1445     case bitc::METADATA_STRING: {
1446       unsigned MDStringLength = Record.size();
1447       SmallString<8> String;
1448       String.resize(MDStringLength);
1449       for (unsigned i = 0; i != MDStringLength; ++i)
1450         String[i] = Record[i];
1451       Value *V = MDString::get(Context,
1452                                StringRef(String.data(), String.size()));
1453       MDValueList.AssignValue(V, NextMDValueNo++);
1454       break;
1455     }
1456     case bitc::METADATA_KIND: {
1457       unsigned RecordLength = Record.size();
1458       if (Record.empty() || RecordLength < 2)
1459         return Error("Invalid METADATA_KIND record");
1460       SmallString<8> Name;
1461       Name.resize(RecordLength-1);
1462       unsigned Kind = Record[0];
1463       for (unsigned i = 1; i != RecordLength; ++i)
1464         Name[i-1] = Record[i];
1465 
1466       unsigned NewKind = TheModule->getMDKindID(Name.str());
1467       if (!MDKindMap.insert(std::make_pair(Kind, NewKind)).second)
1468         return Error("Conflicting METADATA_KIND records");
1469       break;
1470     }
1471     }
1472   }
1473 }
1474 
1475 /// decodeSignRotatedValue - Decode a signed value stored with the sign bit in
1476 /// the LSB for dense VBR encoding.
decodeSignRotatedValue(uint64_t V)1477 uint64_t BitcodeReader::decodeSignRotatedValue(uint64_t V) {
1478   if ((V & 1) == 0)
1479     return V >> 1;
1480   if (V != 1)
1481     return -(V >> 1);
1482   // There is no such thing as -0 with integers.  "-0" really means MININT.
1483   return 1ULL << 63;
1484 }
1485 
1486 /// ResolveGlobalAndAliasInits - Resolve all of the initializers for global
1487 /// values and aliases that we can.
ResolveGlobalAndAliasInits()1488 bool BitcodeReader::ResolveGlobalAndAliasInits() {
1489   std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInitWorklist;
1490   std::vector<std::pair<GlobalAlias*, unsigned> > AliasInitWorklist;
1491 
1492   GlobalInitWorklist.swap(GlobalInits);
1493   AliasInitWorklist.swap(AliasInits);
1494 
1495   while (!GlobalInitWorklist.empty()) {
1496     unsigned ValID = GlobalInitWorklist.back().second;
1497     if (ValID >= ValueList.size()) {
1498       // Not ready to resolve this yet, it requires something later in the file.
1499       GlobalInits.push_back(GlobalInitWorklist.back());
1500     } else {
1501       if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
1502         GlobalInitWorklist.back().first->setInitializer(C);
1503       else
1504         return Error("Global variable initializer is not a constant!");
1505     }
1506     GlobalInitWorklist.pop_back();
1507   }
1508 
1509   while (!AliasInitWorklist.empty()) {
1510     unsigned ValID = AliasInitWorklist.back().second;
1511     if (ValID >= ValueList.size()) {
1512       AliasInits.push_back(AliasInitWorklist.back());
1513     } else {
1514       if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
1515         AliasInitWorklist.back().first->setAliasee(C);
1516       else
1517         return Error("Alias initializer is not a constant!");
1518     }
1519     AliasInitWorklist.pop_back();
1520   }
1521   return false;
1522 }
1523 
ReadWideAPInt(ArrayRef<uint64_t> Vals,unsigned TypeBits)1524 static APInt ReadWideAPInt(ArrayRef<uint64_t> Vals, unsigned TypeBits) {
1525   SmallVector<uint64_t, 8> Words(Vals.size());
1526   std::transform(Vals.begin(), Vals.end(), Words.begin(),
1527                  BitcodeReader::decodeSignRotatedValue);
1528 
1529   return APInt(TypeBits, Words);
1530 }
1531 
ParseConstants()1532 bool BitcodeReader::ParseConstants() {
1533   if (Stream.EnterSubBlock(bitc::CONSTANTS_BLOCK_ID))
1534     return Error("Malformed block record");
1535 
1536   SmallVector<uint64_t, 64> Record;
1537 
1538   // Read all the records for this value table.
1539   Type *CurTy = Type::getInt32Ty(Context);
1540   unsigned NextCstNo = ValueList.size();
1541   while (1) {
1542     BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
1543 
1544     switch (Entry.Kind) {
1545     case BitstreamEntry::SubBlock: // Handled for us already.
1546     case BitstreamEntry::Error:
1547       return Error("malformed block record in AST file");
1548     case BitstreamEntry::EndBlock:
1549       if (NextCstNo != ValueList.size())
1550         return Error("Invalid constant reference!");
1551 
1552       // Once all the constants have been read, go through and resolve forward
1553       // references.
1554       ValueList.ResolveConstantForwardRefs();
1555       return false;
1556     case BitstreamEntry::Record:
1557       // The interesting case.
1558       break;
1559     }
1560 
1561     // Read a record.
1562     Record.clear();
1563     Value *V = 0;
1564     unsigned BitCode = Stream.readRecord(Entry.ID, Record);
1565     switch (BitCode) {
1566     default:  // Default behavior: unknown constant
1567     case bitc::CST_CODE_UNDEF:     // UNDEF
1568       V = UndefValue::get(CurTy);
1569       break;
1570     case bitc::CST_CODE_SETTYPE:   // SETTYPE: [typeid]
1571       if (Record.empty())
1572         return Error("Malformed CST_SETTYPE record");
1573       if (Record[0] >= TypeList.size())
1574         return Error("Invalid Type ID in CST_SETTYPE record");
1575       CurTy = TypeList[Record[0]];
1576       continue;  // Skip the ValueList manipulation.
1577     case bitc::CST_CODE_NULL:      // NULL
1578       V = Constant::getNullValue(CurTy);
1579       break;
1580     case bitc::CST_CODE_INTEGER:   // INTEGER: [intval]
1581       if (!CurTy->isIntegerTy() || Record.empty())
1582         return Error("Invalid CST_INTEGER record");
1583       V = ConstantInt::get(CurTy, decodeSignRotatedValue(Record[0]));
1584       break;
1585     case bitc::CST_CODE_WIDE_INTEGER: {// WIDE_INTEGER: [n x intval]
1586       if (!CurTy->isIntegerTy() || Record.empty())
1587         return Error("Invalid WIDE_INTEGER record");
1588 
1589       APInt VInt = ReadWideAPInt(Record,
1590                                  cast<IntegerType>(CurTy)->getBitWidth());
1591       V = ConstantInt::get(Context, VInt);
1592 
1593       break;
1594     }
1595     case bitc::CST_CODE_FLOAT: {    // FLOAT: [fpval]
1596       if (Record.empty())
1597         return Error("Invalid FLOAT record");
1598       if (CurTy->isHalfTy())
1599         V = ConstantFP::get(Context, APFloat(APFloat::IEEEhalf,
1600                                              APInt(16, (uint16_t)Record[0])));
1601       else if (CurTy->isFloatTy())
1602         V = ConstantFP::get(Context, APFloat(APFloat::IEEEsingle,
1603                                              APInt(32, (uint32_t)Record[0])));
1604       else if (CurTy->isDoubleTy())
1605         V = ConstantFP::get(Context, APFloat(APFloat::IEEEdouble,
1606                                              APInt(64, Record[0])));
1607       else if (CurTy->isX86_FP80Ty()) {
1608         // Bits are not stored the same way as a normal i80 APInt, compensate.
1609         uint64_t Rearrange[2];
1610         Rearrange[0] = (Record[1] & 0xffffLL) | (Record[0] << 16);
1611         Rearrange[1] = Record[0] >> 48;
1612         V = ConstantFP::get(Context, APFloat(APFloat::x87DoubleExtended,
1613                                              APInt(80, Rearrange)));
1614       } else if (CurTy->isFP128Ty())
1615         V = ConstantFP::get(Context, APFloat(APFloat::IEEEquad,
1616                                              APInt(128, Record)));
1617       else if (CurTy->isPPC_FP128Ty())
1618         V = ConstantFP::get(Context, APFloat(APFloat::PPCDoubleDouble,
1619                                              APInt(128, Record)));
1620       else
1621         V = UndefValue::get(CurTy);
1622       break;
1623     }
1624 
1625     case bitc::CST_CODE_AGGREGATE: {// AGGREGATE: [n x value number]
1626       if (Record.empty())
1627         return Error("Invalid CST_AGGREGATE record");
1628 
1629       unsigned Size = Record.size();
1630       SmallVector<Constant*, 16> Elts;
1631 
1632       if (StructType *STy = dyn_cast<StructType>(CurTy)) {
1633         for (unsigned i = 0; i != Size; ++i)
1634           Elts.push_back(ValueList.getConstantFwdRef(Record[i],
1635                                                      STy->getElementType(i)));
1636         V = ConstantStruct::get(STy, Elts);
1637       } else if (ArrayType *ATy = dyn_cast<ArrayType>(CurTy)) {
1638         Type *EltTy = ATy->getElementType();
1639         for (unsigned i = 0; i != Size; ++i)
1640           Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
1641         V = ConstantArray::get(ATy, Elts);
1642       } else if (VectorType *VTy = dyn_cast<VectorType>(CurTy)) {
1643         Type *EltTy = VTy->getElementType();
1644         for (unsigned i = 0; i != Size; ++i)
1645           Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
1646         V = ConstantVector::get(Elts);
1647       } else {
1648         V = UndefValue::get(CurTy);
1649       }
1650       break;
1651     }
1652     case bitc::CST_CODE_STRING: { // STRING: [values]
1653       if (Record.empty())
1654         return Error("Invalid CST_AGGREGATE record");
1655 
1656       ArrayType *ATy = cast<ArrayType>(CurTy);
1657       Type *EltTy = ATy->getElementType();
1658 
1659       unsigned Size = Record.size();
1660       std::vector<Constant*> Elts;
1661       for (unsigned i = 0; i != Size; ++i)
1662         Elts.push_back(ConstantInt::get(EltTy, Record[i]));
1663       V = ConstantArray::get(ATy, Elts);
1664       break;
1665     }
1666     case bitc::CST_CODE_CSTRING: { // CSTRING: [values]
1667       if (Record.empty())
1668         return Error("Invalid CST_AGGREGATE record");
1669 
1670       ArrayType *ATy = cast<ArrayType>(CurTy);
1671       Type *EltTy = ATy->getElementType();
1672 
1673       unsigned Size = Record.size();
1674       std::vector<Constant*> Elts;
1675       for (unsigned i = 0; i != Size; ++i)
1676         Elts.push_back(ConstantInt::get(EltTy, Record[i]));
1677       Elts.push_back(Constant::getNullValue(EltTy));
1678       V = ConstantArray::get(ATy, Elts);
1679       break;
1680     }
1681     case bitc::CST_CODE_CE_BINOP: {  // CE_BINOP: [opcode, opval, opval]
1682       if (Record.size() < 3) return Error("Invalid CE_BINOP record");
1683       int Opc = GetDecodedBinaryOpcode(Record[0], CurTy);
1684       if (Opc < 0) {
1685         V = UndefValue::get(CurTy);  // Unknown binop.
1686       } else {
1687         Constant *LHS = ValueList.getConstantFwdRef(Record[1], CurTy);
1688         Constant *RHS = ValueList.getConstantFwdRef(Record[2], CurTy);
1689         unsigned Flags = 0;
1690         if (Record.size() >= 4) {
1691           if (Opc == Instruction::Add ||
1692               Opc == Instruction::Sub ||
1693               Opc == Instruction::Mul ||
1694               Opc == Instruction::Shl) {
1695             if (Record[3] & (1 << bitc::OBO_NO_SIGNED_WRAP))
1696               Flags |= OverflowingBinaryOperator::NoSignedWrap;
1697             if (Record[3] & (1 << bitc::OBO_NO_UNSIGNED_WRAP))
1698               Flags |= OverflowingBinaryOperator::NoUnsignedWrap;
1699           } else if (Opc == Instruction::SDiv ||
1700                      Opc == Instruction::UDiv ||
1701                      Opc == Instruction::LShr ||
1702                      Opc == Instruction::AShr) {
1703             if (Record[3] & (1 << bitc::PEO_EXACT))
1704               Flags |= SDivOperator::IsExact;
1705           }
1706         }
1707         V = ConstantExpr::get(Opc, LHS, RHS, Flags);
1708       }
1709       break;
1710     }
1711     case bitc::CST_CODE_CE_CAST: {  // CE_CAST: [opcode, opty, opval]
1712       if (Record.size() < 3) return Error("Invalid CE_CAST record");
1713       int Opc = GetDecodedCastOpcode(Record[0]);
1714       if (Opc < 0) {
1715         V = UndefValue::get(CurTy);  // Unknown cast.
1716       } else {
1717         Type *OpTy = getTypeByID(Record[1]);
1718         if (!OpTy) return Error("Invalid CE_CAST record");
1719         Constant *Op = ValueList.getConstantFwdRef(Record[2], OpTy);
1720         V = ConstantExpr::getCast(Opc, Op, CurTy);
1721       }
1722       break;
1723     }
1724     case bitc::CST_CODE_CE_INBOUNDS_GEP:
1725     case bitc::CST_CODE_CE_GEP: {  // CE_GEP:        [n x operands]
1726       if (Record.size() & 1) return Error("Invalid CE_GEP record");
1727       SmallVector<Constant*, 16> Elts;
1728       for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
1729         Type *ElTy = getTypeByID(Record[i]);
1730         if (!ElTy) return Error("Invalid CE_GEP record");
1731         Elts.push_back(ValueList.getConstantFwdRef(Record[i+1], ElTy));
1732       }
1733       ArrayRef<Constant *> Indices(Elts.begin() + 1, Elts.end());
1734       V = ConstantExpr::getGetElementPtr(Elts[0], Indices,
1735                                          BitCode ==
1736                                            bitc::CST_CODE_CE_INBOUNDS_GEP);
1737       break;
1738     }
1739     case bitc::CST_CODE_CE_SELECT:  // CE_SELECT: [opval#, opval#, opval#]
1740       if (Record.size() < 3) return Error("Invalid CE_SELECT record");
1741       V = ConstantExpr::getSelect(ValueList.getConstantFwdRef(Record[0],
1742                                                               Type::getInt1Ty(Context)),
1743                                   ValueList.getConstantFwdRef(Record[1],CurTy),
1744                                   ValueList.getConstantFwdRef(Record[2],CurTy));
1745       break;
1746     case bitc::CST_CODE_CE_EXTRACTELT: { // CE_EXTRACTELT: [opty, opval, opval]
1747       if (Record.size() < 3) return Error("Invalid CE_EXTRACTELT record");
1748       VectorType *OpTy =
1749         dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
1750       if (OpTy == 0) return Error("Invalid CE_EXTRACTELT record");
1751       Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1752       Constant *Op1 = ValueList.getConstantFwdRef(Record[2], Type::getInt32Ty(Context));
1753       V = ConstantExpr::getExtractElement(Op0, Op1);
1754       break;
1755     }
1756     case bitc::CST_CODE_CE_INSERTELT: { // CE_INSERTELT: [opval, opval, opval]
1757       VectorType *OpTy = dyn_cast<VectorType>(CurTy);
1758       if (Record.size() < 3 || OpTy == 0)
1759         return Error("Invalid CE_INSERTELT record");
1760       Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
1761       Constant *Op1 = ValueList.getConstantFwdRef(Record[1],
1762                                                   OpTy->getElementType());
1763       Constant *Op2 = ValueList.getConstantFwdRef(Record[2], Type::getInt32Ty(Context));
1764       V = ConstantExpr::getInsertElement(Op0, Op1, Op2);
1765       break;
1766     }
1767     case bitc::CST_CODE_CE_SHUFFLEVEC: { // CE_SHUFFLEVEC: [opval, opval, opval]
1768       VectorType *OpTy = dyn_cast<VectorType>(CurTy);
1769       if (Record.size() < 3 || OpTy == 0)
1770         return Error("Invalid CE_SHUFFLEVEC record");
1771       Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
1772       Constant *Op1 = ValueList.getConstantFwdRef(Record[1], OpTy);
1773       Type *ShufTy = VectorType::get(Type::getInt32Ty(Context),
1774                                                  OpTy->getNumElements());
1775       Constant *Op2 = ValueList.getConstantFwdRef(Record[2], ShufTy);
1776       V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
1777       break;
1778     }
1779     case bitc::CST_CODE_CE_SHUFVEC_EX: { // [opty, opval, opval, opval]
1780       VectorType *RTy = dyn_cast<VectorType>(CurTy);
1781       VectorType *OpTy =
1782         dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
1783       if (Record.size() < 4 || RTy == 0 || OpTy == 0)
1784         return Error("Invalid CE_SHUFVEC_EX record");
1785       Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1786       Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
1787       Type *ShufTy = VectorType::get(Type::getInt32Ty(Context),
1788                                                  RTy->getNumElements());
1789       Constant *Op2 = ValueList.getConstantFwdRef(Record[3], ShufTy);
1790       V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
1791       break;
1792     }
1793     case bitc::CST_CODE_CE_CMP: {     // CE_CMP: [opty, opval, opval, pred]
1794       if (Record.size() < 4) return Error("Invalid CE_CMP record");
1795       Type *OpTy = getTypeByID(Record[0]);
1796       if (OpTy == 0) return Error("Invalid CE_CMP record");
1797       Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
1798       Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
1799 
1800       if (OpTy->isFPOrFPVectorTy())
1801         V = ConstantExpr::getFCmp(Record[3], Op0, Op1);
1802       else
1803         V = ConstantExpr::getICmp(Record[3], Op0, Op1);
1804       break;
1805     }
1806     case bitc::CST_CODE_INLINEASM: {
1807       if (Record.size() < 2) return Error("Invalid INLINEASM record");
1808       std::string AsmStr, ConstrStr;
1809       bool HasSideEffects = Record[0] & 1;
1810       bool IsAlignStack = Record[0] >> 1;
1811       unsigned AsmStrSize = Record[1];
1812       if (2+AsmStrSize >= Record.size())
1813         return Error("Invalid INLINEASM record");
1814       unsigned ConstStrSize = Record[2+AsmStrSize];
1815       if (3+AsmStrSize+ConstStrSize > Record.size())
1816         return Error("Invalid INLINEASM record");
1817 
1818       for (unsigned i = 0; i != AsmStrSize; ++i)
1819         AsmStr += (char)Record[2+i];
1820       for (unsigned i = 0; i != ConstStrSize; ++i)
1821         ConstrStr += (char)Record[3+AsmStrSize+i];
1822       PointerType *PTy = cast<PointerType>(CurTy);
1823       V = InlineAsm::get(cast<FunctionType>(PTy->getElementType()),
1824                          AsmStr, ConstrStr, HasSideEffects, IsAlignStack);
1825       break;
1826     }
1827     case bitc::CST_CODE_BLOCKADDRESS:{
1828       if (Record.size() < 3) return Error("Invalid CE_BLOCKADDRESS record");
1829       Type *FnTy = getTypeByID(Record[0]);
1830       if (FnTy == 0) return Error("Invalid CE_BLOCKADDRESS record");
1831       Function *Fn =
1832         dyn_cast_or_null<Function>(ValueList.getConstantFwdRef(Record[1],FnTy));
1833       if (Fn == 0) return Error("Invalid CE_BLOCKADDRESS record");
1834 
1835       GlobalVariable *FwdRef = new GlobalVariable(*Fn->getParent(),
1836                                                   Type::getInt8Ty(Context),
1837                                             false, GlobalValue::InternalLinkage,
1838                                                   0, "");
1839       BlockAddrFwdRefs[Fn].push_back(std::make_pair(Record[2], FwdRef));
1840       V = FwdRef;
1841       break;
1842     }
1843     }
1844 
1845     ValueList.AssignValue(V, NextCstNo);
1846     ++NextCstNo;
1847   }
1848 
1849   if (NextCstNo != ValueList.size())
1850     return Error("Invalid constant reference!");
1851 
1852   if (Stream.ReadBlockEnd())
1853     return Error("Error at end of constants block");
1854 
1855   // Once all the constants have been read, go through and resolve forward
1856   // references.
1857   ValueList.ResolveConstantForwardRefs();
1858   return false;
1859 }
1860 
1861 /// RememberAndSkipFunctionBody - When we see the block for a function body,
1862 /// remember where it is and then skip it.  This lets us lazily deserialize the
1863 /// functions.
RememberAndSkipFunctionBody()1864 bool BitcodeReader::RememberAndSkipFunctionBody() {
1865   // Get the function we are talking about.
1866   if (FunctionsWithBodies.empty())
1867     return Error("Insufficient function protos");
1868 
1869   Function *Fn = FunctionsWithBodies.back();
1870   FunctionsWithBodies.pop_back();
1871 
1872   // Save the current stream state.
1873   uint64_t CurBit = Stream.GetCurrentBitNo();
1874   DeferredFunctionInfo[Fn] = CurBit;
1875 
1876   // Skip over the function block for now.
1877   if (Stream.SkipBlock())
1878     return Error("Malformed block record");
1879   return false;
1880 }
1881 
GlobalCleanup()1882 bool BitcodeReader::GlobalCleanup() {
1883   // Patch the initializers for globals and aliases up.
1884   ResolveGlobalAndAliasInits();
1885   if (!GlobalInits.empty() || !AliasInits.empty())
1886     return Error("Malformed global initializer set");
1887 
1888   // Look for intrinsic functions which need to be upgraded at some point
1889   for (Module::iterator FI = TheModule->begin(), FE = TheModule->end();
1890        FI != FE; ++FI) {
1891     Function *NewFn;
1892     if (UpgradeIntrinsicFunction(FI, NewFn))
1893       UpgradedIntrinsics.push_back(std::make_pair(FI, NewFn));
1894   }
1895 
1896   // Look for global variables which need to be renamed.
1897   for (Module::global_iterator
1898          GI = TheModule->global_begin(), GE = TheModule->global_end();
1899        GI != GE; ++GI)
1900     UpgradeGlobalVariable(GI);
1901   // Force deallocation of memory for these vectors to favor the client that
1902   // want lazy deserialization.
1903   std::vector<std::pair<GlobalVariable*, unsigned> >().swap(GlobalInits);
1904   std::vector<std::pair<GlobalAlias*, unsigned> >().swap(AliasInits);
1905   return false;
1906 }
1907 
ParseModule(bool Resume)1908 bool BitcodeReader::ParseModule(bool Resume) {
1909   if (Resume)
1910     Stream.JumpToBit(NextUnreadBit);
1911   else if (Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
1912     return Error("Malformed block record");
1913 
1914   SmallVector<uint64_t, 64> Record;
1915   std::vector<std::string> SectionTable;
1916   std::vector<std::string> GCTable;
1917 
1918   // Read all the records for this module.
1919   while (1) {
1920     BitstreamEntry Entry = Stream.advance();
1921 
1922     switch (Entry.Kind) {
1923     case BitstreamEntry::Error:
1924       Error("malformed module block");
1925       return true;
1926     case BitstreamEntry::EndBlock:
1927       return GlobalCleanup();
1928 
1929     case BitstreamEntry::SubBlock:
1930       switch (Entry.ID) {
1931       default:  // Skip unknown content.
1932         if (Stream.SkipBlock())
1933           return Error("Malformed block record");
1934         break;
1935       case bitc::BLOCKINFO_BLOCK_ID:
1936         if (Stream.ReadBlockInfoBlock())
1937           return Error("Malformed BlockInfoBlock");
1938         break;
1939       case bitc::PARAMATTR_BLOCK_ID:
1940         if (ParseAttributeBlock())
1941           return true;
1942         break;
1943       case bitc::TYPE_BLOCK_ID_NEW:
1944         if (ParseTypeTable())
1945           return true;
1946         break;
1947       case TYPE_BLOCK_ID_OLD_3_0:
1948         if (ParseOldTypeTable())
1949           return true;
1950         break;
1951       case TYPE_SYMTAB_BLOCK_ID_OLD_3_0:
1952         if (ParseOldTypeSymbolTable())
1953           return true;
1954         break;
1955       case bitc::VALUE_SYMTAB_BLOCK_ID:
1956         if (ParseValueSymbolTable())
1957           return true;
1958         SeenValueSymbolTable = true;
1959         break;
1960       case bitc::CONSTANTS_BLOCK_ID:
1961         if (ParseConstants() || ResolveGlobalAndAliasInits())
1962           return true;
1963         break;
1964       case bitc::METADATA_BLOCK_ID:
1965         if (ParseMetadata())
1966           return true;
1967         break;
1968       case bitc::FUNCTION_BLOCK_ID:
1969         // If this is the first function body we've seen, reverse the
1970         // FunctionsWithBodies list.
1971         if (!SeenFirstFunctionBody) {
1972           std::reverse(FunctionsWithBodies.begin(), FunctionsWithBodies.end());
1973           if (GlobalCleanup())
1974             return true;
1975           SeenFirstFunctionBody = true;
1976         }
1977 
1978         if (RememberAndSkipFunctionBody())
1979           return true;
1980         // For streaming bitcode, suspend parsing when we reach the function
1981         // bodies. Subsequent materialization calls will resume it when
1982         // necessary. For streaming, the function bodies must be at the end of
1983         // the bitcode. If the bitcode file is old, the symbol table will be
1984         // at the end instead and will not have been seen yet. In this case,
1985         // just finish the parse now.
1986         if (LazyStreamer && SeenValueSymbolTable) {
1987           NextUnreadBit = Stream.GetCurrentBitNo();
1988           return false;
1989         }
1990         break;
1991         break;
1992       }
1993       continue;
1994 
1995     case BitstreamEntry::Record:
1996       // The interesting case.
1997       break;
1998     }
1999 
2000 
2001     // Read a record.
2002     switch (Stream.readRecord(Entry.ID, Record)) {
2003     default: break;  // Default behavior, ignore unknown content.
2004     case bitc::MODULE_CODE_VERSION: {  // VERSION: [version#]
2005       if (Record.size() < 1)
2006         return Error("Malformed MODULE_CODE_VERSION");
2007       // Only version #0 is supported so far.
2008       if (Record[0] != 0)
2009         return Error("Unknown bitstream version!");
2010       break;
2011     }
2012     case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
2013       std::string S;
2014       if (ConvertToString(Record, 0, S))
2015         return Error("Invalid MODULE_CODE_TRIPLE record");
2016       TheModule->setTargetTriple(S);
2017       break;
2018     }
2019     case bitc::MODULE_CODE_DATALAYOUT: {  // DATALAYOUT: [strchr x N]
2020       std::string S;
2021       if (ConvertToString(Record, 0, S))
2022         return Error("Invalid MODULE_CODE_DATALAYOUT record");
2023       TheModule->setDataLayout(S);
2024       break;
2025     }
2026     case bitc::MODULE_CODE_ASM: {  // ASM: [strchr x N]
2027       std::string S;
2028       if (ConvertToString(Record, 0, S))
2029         return Error("Invalid MODULE_CODE_ASM record");
2030       TheModule->setModuleInlineAsm(S);
2031       break;
2032     }
2033     case bitc::MODULE_CODE_DEPLIB: {  // DEPLIB: [strchr x N]
2034       std::string S;
2035       if (ConvertToString(Record, 0, S))
2036         return Error("Invalid MODULE_CODE_DEPLIB record");
2037       // ANDROID: Ignore value, since we never used it anyways.
2038       // TheModule->addLibrary(S);
2039       break;
2040     }
2041     case bitc::MODULE_CODE_SECTIONNAME: {  // SECTIONNAME: [strchr x N]
2042       std::string S;
2043       if (ConvertToString(Record, 0, S))
2044         return Error("Invalid MODULE_CODE_SECTIONNAME record");
2045       SectionTable.push_back(S);
2046       break;
2047     }
2048     case bitc::MODULE_CODE_GCNAME: {  // SECTIONNAME: [strchr x N]
2049       std::string S;
2050       if (ConvertToString(Record, 0, S))
2051         return Error("Invalid MODULE_CODE_GCNAME record");
2052       GCTable.push_back(S);
2053       break;
2054     }
2055     // GLOBALVAR: [pointer type, isconst, initid,
2056     //             linkage, alignment, section, visibility, threadlocal,
2057     //             unnamed_addr]
2058     case bitc::MODULE_CODE_GLOBALVAR: {
2059       if (Record.size() < 6)
2060         return Error("Invalid MODULE_CODE_GLOBALVAR record");
2061       Type *Ty = getTypeByID(Record[0]);
2062       if (!Ty) return Error("Invalid MODULE_CODE_GLOBALVAR record");
2063       if (!Ty->isPointerTy())
2064         return Error("Global not a pointer type!");
2065       unsigned AddressSpace = cast<PointerType>(Ty)->getAddressSpace();
2066       Ty = cast<PointerType>(Ty)->getElementType();
2067 
2068       bool isConstant = Record[1];
2069       GlobalValue::LinkageTypes Linkage = GetDecodedLinkage(Record[3]);
2070       unsigned Alignment = (1 << Record[4]) >> 1;
2071       std::string Section;
2072       if (Record[5]) {
2073         if (Record[5]-1 >= SectionTable.size())
2074           return Error("Invalid section ID");
2075         Section = SectionTable[Record[5]-1];
2076       }
2077       GlobalValue::VisibilityTypes Visibility = GlobalValue::DefaultVisibility;
2078       if (Record.size() > 6)
2079         Visibility = GetDecodedVisibility(Record[6]);
2080 
2081       GlobalVariable::ThreadLocalMode TLM = GlobalVariable::NotThreadLocal;
2082       if (Record.size() > 7)
2083         TLM = GetDecodedThreadLocalMode(Record[7]);
2084 
2085       bool UnnamedAddr = false;
2086       if (Record.size() > 8)
2087         UnnamedAddr = Record[8];
2088 
2089       GlobalVariable *NewGV =
2090         new GlobalVariable(*TheModule, Ty, isConstant, Linkage, 0, "", 0,
2091                            TLM, AddressSpace);
2092       NewGV->setAlignment(Alignment);
2093       if (!Section.empty())
2094         NewGV->setSection(Section);
2095       NewGV->setVisibility(Visibility);
2096       NewGV->setUnnamedAddr(UnnamedAddr);
2097 
2098       ValueList.push_back(NewGV);
2099 
2100       // Remember which value to use for the global initializer.
2101       if (unsigned InitID = Record[2])
2102         GlobalInits.push_back(std::make_pair(NewGV, InitID-1));
2103       break;
2104     }
2105     // FUNCTION:  [type, callingconv, isproto, linkage, paramattr,
2106     //             alignment, section, visibility, gc, unnamed_addr]
2107     case bitc::MODULE_CODE_FUNCTION: {
2108       if (Record.size() < 8)
2109         return Error("Invalid MODULE_CODE_FUNCTION record");
2110       Type *Ty = getTypeByID(Record[0]);
2111       if (!Ty) return Error("Invalid MODULE_CODE_FUNCTION record");
2112       if (!Ty->isPointerTy())
2113         return Error("Function not a pointer type!");
2114       FunctionType *FTy =
2115         dyn_cast<FunctionType>(cast<PointerType>(Ty)->getElementType());
2116       if (!FTy)
2117         return Error("Function not a pointer to function type!");
2118 
2119       Function *Func = Function::Create(FTy, GlobalValue::ExternalLinkage,
2120                                         "", TheModule);
2121 
2122       Func->setCallingConv(static_cast<CallingConv::ID>(Record[1]));
2123       bool isProto = Record[2];
2124       Func->setLinkage(GetDecodedLinkage(Record[3]));
2125       Func->setAttributes(getAttributes(Record[4]));
2126 
2127       Func->setAlignment((1 << Record[5]) >> 1);
2128       if (Record[6]) {
2129         if (Record[6]-1 >= SectionTable.size())
2130           return Error("Invalid section ID");
2131         Func->setSection(SectionTable[Record[6]-1]);
2132       }
2133       Func->setVisibility(GetDecodedVisibility(Record[7]));
2134       if (Record.size() > 8 && Record[8]) {
2135         if (Record[8]-1 > GCTable.size())
2136           return Error("Invalid GC ID");
2137         Func->setGC(GCTable[Record[8]-1].c_str());
2138       }
2139       bool UnnamedAddr = false;
2140       if (Record.size() > 9)
2141         UnnamedAddr = Record[9];
2142       Func->setUnnamedAddr(UnnamedAddr);
2143       ValueList.push_back(Func);
2144 
2145       // If this is a function with a body, remember the prototype we are
2146       // creating now, so that we can match up the body with them later.
2147       if (!isProto) {
2148         FunctionsWithBodies.push_back(Func);
2149         if (LazyStreamer) DeferredFunctionInfo[Func] = 0;
2150       }
2151       break;
2152     }
2153     // ALIAS: [alias type, aliasee val#, linkage]
2154     // ALIAS: [alias type, aliasee val#, linkage, visibility]
2155     case bitc::MODULE_CODE_ALIAS: {
2156       if (Record.size() < 3)
2157         return Error("Invalid MODULE_ALIAS record");
2158       Type *Ty = getTypeByID(Record[0]);
2159       if (!Ty) return Error("Invalid MODULE_ALIAS record");
2160       if (!Ty->isPointerTy())
2161         return Error("Function not a pointer type!");
2162 
2163       GlobalAlias *NewGA = new GlobalAlias(Ty, GetDecodedLinkage(Record[2]),
2164                                            "", 0, TheModule);
2165       // Old bitcode files didn't have visibility field.
2166       if (Record.size() > 3)
2167         NewGA->setVisibility(GetDecodedVisibility(Record[3]));
2168       ValueList.push_back(NewGA);
2169       AliasInits.push_back(std::make_pair(NewGA, Record[1]));
2170       break;
2171     }
2172     /// MODULE_CODE_PURGEVALS: [numvals]
2173     case bitc::MODULE_CODE_PURGEVALS:
2174       // Trim down the value list to the specified size.
2175       if (Record.size() < 1 || Record[0] > ValueList.size())
2176         return Error("Invalid MODULE_PURGEVALS record");
2177       ValueList.shrinkTo(Record[0]);
2178       break;
2179     }
2180     Record.clear();
2181   }
2182 }
2183 
ParseBitcodeInto(Module * M)2184 bool BitcodeReader::ParseBitcodeInto(Module *M) {
2185   TheModule = 0;
2186 
2187   if (InitStream()) return true;
2188 
2189   // Sniff for the signature.
2190   if (Stream.Read(8) != 'B' ||
2191       Stream.Read(8) != 'C' ||
2192       Stream.Read(4) != 0x0 ||
2193       Stream.Read(4) != 0xC ||
2194       Stream.Read(4) != 0xE ||
2195       Stream.Read(4) != 0xD)
2196     return Error("Invalid bitcode signature");
2197 
2198   // We expect a number of well-defined blocks, though we don't necessarily
2199   // need to understand them all.
2200   while (1) {
2201     if (Stream.AtEndOfStream())
2202       return false;
2203 
2204     BitstreamEntry Entry =
2205       Stream.advance(BitstreamCursor::AF_DontAutoprocessAbbrevs);
2206 
2207     switch (Entry.Kind) {
2208     case BitstreamEntry::Error:
2209       Error("malformed module file");
2210       return true;
2211     case BitstreamEntry::EndBlock:
2212       return false;
2213 
2214     case BitstreamEntry::SubBlock:
2215       switch (Entry.ID) {
2216       case bitc::BLOCKINFO_BLOCK_ID:
2217         if (Stream.ReadBlockInfoBlock())
2218           return Error("Malformed BlockInfoBlock");
2219         break;
2220       case bitc::MODULE_BLOCK_ID:
2221         // Reject multiple MODULE_BLOCK's in a single bitstream.
2222         if (TheModule)
2223           return Error("Multiple MODULE_BLOCKs in same stream");
2224         TheModule = M;
2225         if (ParseModule(false))
2226           return true;
2227         if (LazyStreamer) return false;
2228         break;
2229       default:
2230         if (Stream.SkipBlock())
2231           return Error("Malformed block record");
2232         break;
2233       }
2234       continue;
2235     case BitstreamEntry::Record:
2236       // There should be no records in the top-level of blocks.
2237 
2238       // The ranlib in Xcode 4 will align archive members by appending newlines
2239       // to the end of them. If this file size is a multiple of 4 but not 8, we
2240       // have to read and ignore these final 4 bytes :-(
2241       if (Stream.getAbbrevIDWidth() == 2 && Entry.ID == 2 &&
2242           Stream.Read(6) == 2 && Stream.Read(24) == 0xa0a0a &&
2243           Stream.AtEndOfStream())
2244         return false;
2245 
2246       return Error("Invalid record at top-level");
2247     }
2248   }
2249 }
2250 
ParseModuleTriple(std::string & Triple)2251 bool BitcodeReader::ParseModuleTriple(std::string &Triple) {
2252   if (Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
2253     return Error("Malformed block record");
2254 
2255   SmallVector<uint64_t, 64> Record;
2256 
2257   // Read all the records for this module.
2258   while (1) {
2259     BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
2260 
2261     switch (Entry.Kind) {
2262     case BitstreamEntry::SubBlock: // Handled for us already.
2263     case BitstreamEntry::Error:
2264       return Error("malformed module block");
2265     case BitstreamEntry::EndBlock:
2266       return false;
2267     case BitstreamEntry::Record:
2268       // The interesting case.
2269       break;
2270     }
2271 
2272     // Read a record.
2273     switch (Stream.readRecord(Entry.ID, Record)) {
2274     default: break;  // Default behavior, ignore unknown content.
2275     case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
2276       std::string S;
2277       if (ConvertToString(Record, 0, S))
2278         return Error("Invalid MODULE_CODE_TRIPLE record");
2279       Triple = S;
2280       break;
2281     }
2282     }
2283     Record.clear();
2284   }
2285 }
2286 
ParseTriple(std::string & Triple)2287 bool BitcodeReader::ParseTriple(std::string &Triple) {
2288   if (InitStream()) return true;
2289 
2290   // Sniff for the signature.
2291   if (Stream.Read(8) != 'B' ||
2292       Stream.Read(8) != 'C' ||
2293       Stream.Read(4) != 0x0 ||
2294       Stream.Read(4) != 0xC ||
2295       Stream.Read(4) != 0xE ||
2296       Stream.Read(4) != 0xD)
2297     return Error("Invalid bitcode signature");
2298 
2299   // We expect a number of well-defined blocks, though we don't necessarily
2300   // need to understand them all.
2301   while (1) {
2302     BitstreamEntry Entry = Stream.advance();
2303 
2304     switch (Entry.Kind) {
2305     case BitstreamEntry::Error:
2306       Error("malformed module file");
2307       return true;
2308     case BitstreamEntry::EndBlock:
2309       return false;
2310 
2311     case BitstreamEntry::SubBlock:
2312       if (Entry.ID == bitc::MODULE_BLOCK_ID)
2313         return ParseModuleTriple(Triple);
2314 
2315       // Ignore other sub-blocks.
2316       if (Stream.SkipBlock()) {
2317         Error("malformed block record in AST file");
2318         return true;
2319       }
2320       continue;
2321 
2322     case BitstreamEntry::Record:
2323       Stream.skipRecord(Entry.ID);
2324       continue;
2325     }
2326   }
2327 }
2328 
2329 /// ParseMetadataAttachment - Parse metadata attachments.
ParseMetadataAttachment()2330 bool BitcodeReader::ParseMetadataAttachment() {
2331   if (Stream.EnterSubBlock(bitc::METADATA_ATTACHMENT_ID))
2332     return Error("Malformed block record");
2333 
2334   SmallVector<uint64_t, 64> Record;
2335   while (1) {
2336     BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
2337 
2338     switch (Entry.Kind) {
2339     case BitstreamEntry::SubBlock: // Handled for us already.
2340     case BitstreamEntry::Error:
2341       return Error("malformed metadata block");
2342     case BitstreamEntry::EndBlock:
2343       return false;
2344     case BitstreamEntry::Record:
2345       // The interesting case.
2346       break;
2347     }
2348 
2349     // Read a metadata attachment record.
2350     Record.clear();
2351     switch (Stream.readRecord(Entry.ID, Record)) {
2352     default:  // Default behavior: ignore.
2353       break;
2354     case bitc::METADATA_ATTACHMENT: {
2355       unsigned RecordLength = Record.size();
2356       if (Record.empty() || (RecordLength - 1) % 2 == 1)
2357         return Error ("Invalid METADATA_ATTACHMENT reader!");
2358       Instruction *Inst = InstructionList[Record[0]];
2359       for (unsigned i = 1; i != RecordLength; i = i+2) {
2360         unsigned Kind = Record[i];
2361         DenseMap<unsigned, unsigned>::iterator I =
2362           MDKindMap.find(Kind);
2363         if (I == MDKindMap.end())
2364           return Error("Invalid metadata kind ID");
2365         Value *Node = MDValueList.getValueFwdRef(Record[i+1]);
2366         Inst->setMetadata(I->second, cast<MDNode>(Node));
2367       }
2368       break;
2369     }
2370     }
2371   }
2372 }
2373 
2374 /// ParseFunctionBody - Lazily parse the specified function body block.
ParseFunctionBody(Function * F)2375 bool BitcodeReader::ParseFunctionBody(Function *F) {
2376   if (Stream.EnterSubBlock(bitc::FUNCTION_BLOCK_ID))
2377     return Error("Malformed block record");
2378 
2379   InstructionList.clear();
2380   unsigned ModuleValueListSize = ValueList.size();
2381   unsigned ModuleMDValueListSize = MDValueList.size();
2382 
2383   // Add all the function arguments to the value table.
2384   for(Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
2385     ValueList.push_back(I);
2386 
2387   unsigned NextValueNo = ValueList.size();
2388   BasicBlock *CurBB = 0;
2389   unsigned CurBBNo = 0;
2390 
2391   DebugLoc LastLoc;
2392 
2393   // Read all the records.
2394   SmallVector<uint64_t, 64> Record;
2395   while (1) {
2396     unsigned Code = Stream.ReadCode();
2397     if (Code == bitc::END_BLOCK) {
2398       if (Stream.ReadBlockEnd())
2399         return Error("Error at end of function block");
2400       break;
2401     }
2402 
2403     if (Code == bitc::ENTER_SUBBLOCK) {
2404       switch (Stream.ReadSubBlockID()) {
2405       default:  // Skip unknown content.
2406         if (Stream.SkipBlock())
2407           return Error("Malformed block record");
2408         break;
2409       case bitc::CONSTANTS_BLOCK_ID:
2410         if (ParseConstants()) return true;
2411         NextValueNo = ValueList.size();
2412         break;
2413       case bitc::VALUE_SYMTAB_BLOCK_ID:
2414         if (ParseValueSymbolTable()) return true;
2415         break;
2416       case bitc::METADATA_ATTACHMENT_ID:
2417         if (ParseMetadataAttachment()) return true;
2418         break;
2419       case bitc::METADATA_BLOCK_ID:
2420         if (ParseMetadata()) return true;
2421         break;
2422       }
2423       continue;
2424     }
2425 
2426     if (Code == bitc::DEFINE_ABBREV) {
2427       Stream.ReadAbbrevRecord();
2428       continue;
2429     }
2430 
2431     // Read a record.
2432     Record.clear();
2433     Instruction *I = 0;
2434     unsigned BitCode = Stream.readRecord(Code, Record);
2435     switch (BitCode) {
2436     default: // Default behavior: reject
2437       return Error("Unknown instruction");
2438     case bitc::FUNC_CODE_DECLAREBLOCKS:     // DECLAREBLOCKS: [nblocks]
2439       if (Record.size() < 1 || Record[0] == 0)
2440         return Error("Invalid DECLAREBLOCKS record");
2441       // Create all the basic blocks for the function.
2442       FunctionBBs.resize(Record[0]);
2443       for (unsigned i = 0, e = FunctionBBs.size(); i != e; ++i)
2444         FunctionBBs[i] = BasicBlock::Create(Context, "", F);
2445       CurBB = FunctionBBs[0];
2446       continue;
2447 
2448     case bitc::FUNC_CODE_DEBUG_LOC_AGAIN:  // DEBUG_LOC_AGAIN
2449       // This record indicates that the last instruction is at the same
2450       // location as the previous instruction with a location.
2451       I = 0;
2452 
2453       // Get the last instruction emitted.
2454       if (CurBB && !CurBB->empty())
2455         I = &CurBB->back();
2456       else if (CurBBNo && FunctionBBs[CurBBNo-1] &&
2457                !FunctionBBs[CurBBNo-1]->empty())
2458         I = &FunctionBBs[CurBBNo-1]->back();
2459 
2460       if (I == 0) return Error("Invalid DEBUG_LOC_AGAIN record");
2461       I->setDebugLoc(LastLoc);
2462       I = 0;
2463       continue;
2464 
2465     case bitc::FUNC_CODE_DEBUG_LOC: {      // DEBUG_LOC: [line, col, scope, ia]
2466       I = 0;     // Get the last instruction emitted.
2467       if (CurBB && !CurBB->empty())
2468         I = &CurBB->back();
2469       else if (CurBBNo && FunctionBBs[CurBBNo-1] &&
2470                !FunctionBBs[CurBBNo-1]->empty())
2471         I = &FunctionBBs[CurBBNo-1]->back();
2472       if (I == 0 || Record.size() < 4)
2473         return Error("Invalid FUNC_CODE_DEBUG_LOC record");
2474 
2475       unsigned Line = Record[0], Col = Record[1];
2476       unsigned ScopeID = Record[2], IAID = Record[3];
2477 
2478       MDNode *Scope = 0, *IA = 0;
2479       if (ScopeID) Scope = cast<MDNode>(MDValueList.getValueFwdRef(ScopeID-1));
2480       if (IAID)    IA = cast<MDNode>(MDValueList.getValueFwdRef(IAID-1));
2481       LastLoc = DebugLoc::get(Line, Col, Scope, IA);
2482       I->setDebugLoc(LastLoc);
2483       I = 0;
2484       continue;
2485     }
2486 
2487     case bitc::FUNC_CODE_INST_BINOP: {    // BINOP: [opval, ty, opval, opcode]
2488       unsigned OpNum = 0;
2489       Value *LHS, *RHS;
2490       if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
2491           getValue(Record, OpNum, LHS->getType(), RHS) ||
2492           OpNum+1 > Record.size())
2493         return Error("Invalid BINOP record");
2494 
2495       int Opc = GetDecodedBinaryOpcode(Record[OpNum++], LHS->getType());
2496       if (Opc == -1) return Error("Invalid BINOP record");
2497       I = BinaryOperator::Create((Instruction::BinaryOps)Opc, LHS, RHS);
2498       InstructionList.push_back(I);
2499       if (OpNum < Record.size()) {
2500         if (Opc == Instruction::Add ||
2501             Opc == Instruction::Sub ||
2502             Opc == Instruction::Mul ||
2503             Opc == Instruction::Shl) {
2504           if (Record[OpNum] & (1 << bitc::OBO_NO_SIGNED_WRAP))
2505             cast<BinaryOperator>(I)->setHasNoSignedWrap(true);
2506           if (Record[OpNum] & (1 << bitc::OBO_NO_UNSIGNED_WRAP))
2507             cast<BinaryOperator>(I)->setHasNoUnsignedWrap(true);
2508         } else if (Opc == Instruction::SDiv ||
2509                    Opc == Instruction::UDiv ||
2510                    Opc == Instruction::LShr ||
2511                    Opc == Instruction::AShr) {
2512           if (Record[OpNum] & (1 << bitc::PEO_EXACT))
2513             cast<BinaryOperator>(I)->setIsExact(true);
2514         }
2515       }
2516       break;
2517     }
2518     case bitc::FUNC_CODE_INST_CAST: {    // CAST: [opval, opty, destty, castopc]
2519       unsigned OpNum = 0;
2520       Value *Op;
2521       if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
2522           OpNum+2 != Record.size())
2523         return Error("Invalid CAST record");
2524 
2525       Type *ResTy = getTypeByID(Record[OpNum]);
2526       int Opc = GetDecodedCastOpcode(Record[OpNum+1]);
2527       if (Opc == -1 || ResTy == 0)
2528         return Error("Invalid CAST record");
2529       I = CastInst::Create((Instruction::CastOps)Opc, Op, ResTy);
2530       InstructionList.push_back(I);
2531       break;
2532     }
2533     case bitc::FUNC_CODE_INST_INBOUNDS_GEP:
2534     case bitc::FUNC_CODE_INST_GEP: { // GEP: [n x operands]
2535       unsigned OpNum = 0;
2536       Value *BasePtr;
2537       if (getValueTypePair(Record, OpNum, NextValueNo, BasePtr))
2538         return Error("Invalid GEP record");
2539 
2540       SmallVector<Value*, 16> GEPIdx;
2541       while (OpNum != Record.size()) {
2542         Value *Op;
2543         if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2544           return Error("Invalid GEP record");
2545         GEPIdx.push_back(Op);
2546       }
2547 
2548       I = GetElementPtrInst::Create(BasePtr, GEPIdx);
2549       InstructionList.push_back(I);
2550       if (BitCode == bitc::FUNC_CODE_INST_INBOUNDS_GEP)
2551         cast<GetElementPtrInst>(I)->setIsInBounds(true);
2552       break;
2553     }
2554 
2555     case bitc::FUNC_CODE_INST_EXTRACTVAL: {
2556                                        // EXTRACTVAL: [opty, opval, n x indices]
2557       unsigned OpNum = 0;
2558       Value *Agg;
2559       if (getValueTypePair(Record, OpNum, NextValueNo, Agg))
2560         return Error("Invalid EXTRACTVAL record");
2561 
2562       SmallVector<unsigned, 4> EXTRACTVALIdx;
2563       for (unsigned RecSize = Record.size();
2564            OpNum != RecSize; ++OpNum) {
2565         uint64_t Index = Record[OpNum];
2566         if ((unsigned)Index != Index)
2567           return Error("Invalid EXTRACTVAL index");
2568         EXTRACTVALIdx.push_back((unsigned)Index);
2569       }
2570 
2571       I = ExtractValueInst::Create(Agg, EXTRACTVALIdx);
2572       InstructionList.push_back(I);
2573       break;
2574     }
2575 
2576     case bitc::FUNC_CODE_INST_INSERTVAL: {
2577                            // INSERTVAL: [opty, opval, opty, opval, n x indices]
2578       unsigned OpNum = 0;
2579       Value *Agg;
2580       if (getValueTypePair(Record, OpNum, NextValueNo, Agg))
2581         return Error("Invalid INSERTVAL record");
2582       Value *Val;
2583       if (getValueTypePair(Record, OpNum, NextValueNo, Val))
2584         return Error("Invalid INSERTVAL record");
2585 
2586       SmallVector<unsigned, 4> INSERTVALIdx;
2587       for (unsigned RecSize = Record.size();
2588            OpNum != RecSize; ++OpNum) {
2589         uint64_t Index = Record[OpNum];
2590         if ((unsigned)Index != Index)
2591           return Error("Invalid INSERTVAL index");
2592         INSERTVALIdx.push_back((unsigned)Index);
2593       }
2594 
2595       I = InsertValueInst::Create(Agg, Val, INSERTVALIdx);
2596       InstructionList.push_back(I);
2597       break;
2598     }
2599 
2600     case bitc::FUNC_CODE_INST_SELECT: { // SELECT: [opval, ty, opval, opval]
2601       // obsolete form of select
2602       // handles select i1 ... in old bitcode
2603       unsigned OpNum = 0;
2604       Value *TrueVal, *FalseVal, *Cond;
2605       if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
2606           getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
2607           getValue(Record, OpNum, Type::getInt1Ty(Context), Cond))
2608         return Error("Invalid SELECT record");
2609 
2610       I = SelectInst::Create(Cond, TrueVal, FalseVal);
2611       InstructionList.push_back(I);
2612       break;
2613     }
2614 
2615     case bitc::FUNC_CODE_INST_VSELECT: {// VSELECT: [ty,opval,opval,predty,pred]
2616       // new form of select
2617       // handles select i1 or select [N x i1]
2618       unsigned OpNum = 0;
2619       Value *TrueVal, *FalseVal, *Cond;
2620       if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
2621           getValue(Record, OpNum, TrueVal->getType(), FalseVal) ||
2622           getValueTypePair(Record, OpNum, NextValueNo, Cond))
2623         return Error("Invalid SELECT record");
2624 
2625       // select condition can be either i1 or [N x i1]
2626       if (VectorType* vector_type =
2627           dyn_cast<VectorType>(Cond->getType())) {
2628         // expect <n x i1>
2629         if (vector_type->getElementType() != Type::getInt1Ty(Context))
2630           return Error("Invalid SELECT condition type");
2631       } else {
2632         // expect i1
2633         if (Cond->getType() != Type::getInt1Ty(Context))
2634           return Error("Invalid SELECT condition type");
2635       }
2636 
2637       I = SelectInst::Create(Cond, TrueVal, FalseVal);
2638       InstructionList.push_back(I);
2639       break;
2640     }
2641 
2642     case bitc::FUNC_CODE_INST_EXTRACTELT: { // EXTRACTELT: [opty, opval, opval]
2643       unsigned OpNum = 0;
2644       Value *Vec, *Idx;
2645       if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
2646           getValue(Record, OpNum, Type::getInt32Ty(Context), Idx))
2647         return Error("Invalid EXTRACTELT record");
2648       I = ExtractElementInst::Create(Vec, Idx);
2649       InstructionList.push_back(I);
2650       break;
2651     }
2652 
2653     case bitc::FUNC_CODE_INST_INSERTELT: { // INSERTELT: [ty, opval,opval,opval]
2654       unsigned OpNum = 0;
2655       Value *Vec, *Elt, *Idx;
2656       if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
2657           getValue(Record, OpNum,
2658                    cast<VectorType>(Vec->getType())->getElementType(), Elt) ||
2659           getValue(Record, OpNum, Type::getInt32Ty(Context), Idx))
2660         return Error("Invalid INSERTELT record");
2661       I = InsertElementInst::Create(Vec, Elt, Idx);
2662       InstructionList.push_back(I);
2663       break;
2664     }
2665 
2666     case bitc::FUNC_CODE_INST_SHUFFLEVEC: {// SHUFFLEVEC: [opval,ty,opval,opval]
2667       unsigned OpNum = 0;
2668       Value *Vec1, *Vec2, *Mask;
2669       if (getValueTypePair(Record, OpNum, NextValueNo, Vec1) ||
2670           getValue(Record, OpNum, Vec1->getType(), Vec2))
2671         return Error("Invalid SHUFFLEVEC record");
2672 
2673       if (getValueTypePair(Record, OpNum, NextValueNo, Mask))
2674         return Error("Invalid SHUFFLEVEC record");
2675       I = new ShuffleVectorInst(Vec1, Vec2, Mask);
2676       InstructionList.push_back(I);
2677       break;
2678     }
2679 
2680     case bitc::FUNC_CODE_INST_CMP:   // CMP: [opty, opval, opval, pred]
2681       // Old form of ICmp/FCmp returning bool
2682       // Existed to differentiate between icmp/fcmp and vicmp/vfcmp which were
2683       // both legal on vectors but had different behaviour.
2684     case bitc::FUNC_CODE_INST_CMP2: { // CMP2: [opty, opval, opval, pred]
2685       // FCmp/ICmp returning bool or vector of bool
2686 
2687       unsigned OpNum = 0;
2688       Value *LHS, *RHS;
2689       if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
2690           getValue(Record, OpNum, LHS->getType(), RHS) ||
2691           OpNum+1 != Record.size())
2692         return Error("Invalid CMP record");
2693 
2694       if (LHS->getType()->isFPOrFPVectorTy())
2695         I = new FCmpInst((FCmpInst::Predicate)Record[OpNum], LHS, RHS);
2696       else
2697         I = new ICmpInst((ICmpInst::Predicate)Record[OpNum], LHS, RHS);
2698       InstructionList.push_back(I);
2699       break;
2700     }
2701 
2702     case bitc::FUNC_CODE_INST_RET: // RET: [opty,opval<optional>]
2703       {
2704         unsigned Size = Record.size();
2705         if (Size == 0) {
2706           I = ReturnInst::Create(Context);
2707           InstructionList.push_back(I);
2708           break;
2709         }
2710 
2711         unsigned OpNum = 0;
2712         Value *Op = NULL;
2713         if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2714           return Error("Invalid RET record");
2715         if (OpNum != Record.size())
2716           return Error("Invalid RET record");
2717 
2718         I = ReturnInst::Create(Context, Op);
2719         InstructionList.push_back(I);
2720         break;
2721       }
2722     case bitc::FUNC_CODE_INST_BR: { // BR: [bb#, bb#, opval] or [bb#]
2723       if (Record.size() != 1 && Record.size() != 3)
2724         return Error("Invalid BR record");
2725       BasicBlock *TrueDest = getBasicBlock(Record[0]);
2726       if (TrueDest == 0)
2727         return Error("Invalid BR record");
2728 
2729       if (Record.size() == 1) {
2730         I = BranchInst::Create(TrueDest);
2731         InstructionList.push_back(I);
2732       }
2733       else {
2734         BasicBlock *FalseDest = getBasicBlock(Record[1]);
2735         Value *Cond = getFnValueByID(Record[2], Type::getInt1Ty(Context));
2736         if (FalseDest == 0 || Cond == 0)
2737           return Error("Invalid BR record");
2738         I = BranchInst::Create(TrueDest, FalseDest, Cond);
2739         InstructionList.push_back(I);
2740       }
2741       break;
2742     }
2743     case bitc::FUNC_CODE_INST_SWITCH: { // SWITCH: [opty, op0, op1, ...]
2744       if (Record.size() < 3 || (Record.size() & 1) == 0)
2745         return Error("Invalid SWITCH record");
2746       Type *OpTy = getTypeByID(Record[0]);
2747       Value *Cond = getFnValueByID(Record[1], OpTy);
2748       BasicBlock *Default = getBasicBlock(Record[2]);
2749       if (OpTy == 0 || Cond == 0 || Default == 0)
2750         return Error("Invalid SWITCH record");
2751       unsigned NumCases = (Record.size()-3)/2;
2752       SwitchInst *SI = SwitchInst::Create(Cond, Default, NumCases);
2753       InstructionList.push_back(SI);
2754       for (unsigned i = 0, e = NumCases; i != e; ++i) {
2755         ConstantInt *CaseVal =
2756           dyn_cast_or_null<ConstantInt>(getFnValueByID(Record[3+i*2], OpTy));
2757         BasicBlock *DestBB = getBasicBlock(Record[1+3+i*2]);
2758         if (CaseVal == 0 || DestBB == 0) {
2759           delete SI;
2760           return Error("Invalid SWITCH record!");
2761         }
2762         SI->addCase(CaseVal, DestBB);
2763       }
2764       I = SI;
2765       break;
2766     }
2767     case bitc::FUNC_CODE_INST_INDIRECTBR: { // INDIRECTBR: [opty, op0, op1, ...]
2768       if (Record.size() < 2)
2769         return Error("Invalid INDIRECTBR record");
2770       Type *OpTy = getTypeByID(Record[0]);
2771       Value *Address = getFnValueByID(Record[1], OpTy);
2772       if (OpTy == 0 || Address == 0)
2773         return Error("Invalid INDIRECTBR record");
2774       unsigned NumDests = Record.size()-2;
2775       IndirectBrInst *IBI = IndirectBrInst::Create(Address, NumDests);
2776       InstructionList.push_back(IBI);
2777       for (unsigned i = 0, e = NumDests; i != e; ++i) {
2778         if (BasicBlock *DestBB = getBasicBlock(Record[2+i])) {
2779           IBI->addDestination(DestBB);
2780         } else {
2781           delete IBI;
2782           return Error("Invalid INDIRECTBR record!");
2783         }
2784       }
2785       I = IBI;
2786       break;
2787     }
2788 
2789     case bitc::FUNC_CODE_INST_INVOKE: {
2790       // INVOKE: [attrs, cc, normBB, unwindBB, fnty, op0,op1,op2, ...]
2791       if (Record.size() < 4) return Error("Invalid INVOKE record");
2792       AttributeSet PAL = getAttributes(Record[0]);
2793       unsigned CCInfo = Record[1];
2794       BasicBlock *NormalBB = getBasicBlock(Record[2]);
2795       BasicBlock *UnwindBB = getBasicBlock(Record[3]);
2796 
2797       unsigned OpNum = 4;
2798       Value *Callee;
2799       if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
2800         return Error("Invalid INVOKE record");
2801 
2802       PointerType *CalleeTy = dyn_cast<PointerType>(Callee->getType());
2803       FunctionType *FTy = !CalleeTy ? 0 :
2804         dyn_cast<FunctionType>(CalleeTy->getElementType());
2805 
2806       // Check that the right number of fixed parameters are here.
2807       if (FTy == 0 || NormalBB == 0 || UnwindBB == 0 ||
2808           Record.size() < OpNum+FTy->getNumParams())
2809         return Error("Invalid INVOKE record");
2810 
2811       SmallVector<Value*, 16> Ops;
2812       for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
2813         Ops.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
2814         if (Ops.back() == 0) return Error("Invalid INVOKE record");
2815       }
2816 
2817       if (!FTy->isVarArg()) {
2818         if (Record.size() != OpNum)
2819           return Error("Invalid INVOKE record");
2820       } else {
2821         // Read type/value pairs for varargs params.
2822         while (OpNum != Record.size()) {
2823           Value *Op;
2824           if (getValueTypePair(Record, OpNum, NextValueNo, Op))
2825             return Error("Invalid INVOKE record");
2826           Ops.push_back(Op);
2827         }
2828       }
2829 
2830       I = InvokeInst::Create(Callee, NormalBB, UnwindBB, Ops);
2831       InstructionList.push_back(I);
2832       cast<InvokeInst>(I)->setCallingConv(
2833         static_cast<CallingConv::ID>(CCInfo));
2834       cast<InvokeInst>(I)->setAttributes(PAL);
2835       break;
2836     }
2837     case bitc::FUNC_CODE_INST_RESUME: { // RESUME: [opval]
2838       unsigned Idx = 0;
2839       Value *Val = 0;
2840       if (getValueTypePair(Record, Idx, NextValueNo, Val))
2841         return Error("Invalid RESUME record");
2842       I = ResumeInst::Create(Val);
2843       InstructionList.push_back(I);
2844       break;
2845     }
2846     case FUNC_CODE_INST_UNWIND_2_7: { // UNWIND_OLD
2847       // 'unwind' instruction has been removed in LLVM 3.1
2848       // Replace 'unwind' with 'landingpad' and 'resume'.
2849       Type *ExnTy = StructType::get(Type::getInt8PtrTy(Context),
2850                                     Type::getInt32Ty(Context), NULL);
2851       Constant *PersFn =
2852         F->getParent()->
2853         getOrInsertFunction("__gcc_personality_v0",
2854                           FunctionType::get(Type::getInt32Ty(Context), true));
2855 
2856       LandingPadInst *LP = LandingPadInst::Create(ExnTy, PersFn, 1);
2857       LP->setCleanup(true);
2858 
2859       CurBB->getInstList().push_back(LP);
2860       I = ResumeInst::Create(LP);
2861       InstructionList.push_back(I);
2862       break;
2863     }
2864     case bitc::FUNC_CODE_INST_UNREACHABLE: // UNREACHABLE
2865       I = new UnreachableInst(Context);
2866       InstructionList.push_back(I);
2867       break;
2868     case bitc::FUNC_CODE_INST_PHI: { // PHI: [ty, val0,bb0, ...]
2869       if (Record.size() < 1 || ((Record.size()-1)&1))
2870         return Error("Invalid PHI record");
2871       Type *Ty = getTypeByID(Record[0]);
2872       if (!Ty) return Error("Invalid PHI record");
2873 
2874       PHINode *PN = PHINode::Create(Ty, (Record.size()-1)/2);
2875       InstructionList.push_back(PN);
2876 
2877       for (unsigned i = 0, e = Record.size()-1; i != e; i += 2) {
2878         Value *V = getFnValueByID(Record[1+i], Ty);
2879         BasicBlock *BB = getBasicBlock(Record[2+i]);
2880         if (!V || !BB) return Error("Invalid PHI record");
2881         PN->addIncoming(V, BB);
2882       }
2883       I = PN;
2884       break;
2885     }
2886 
2887     case bitc::FUNC_CODE_INST_LANDINGPAD: {
2888       // LANDINGPAD: [ty, val, val, num, (id0,val0 ...)?]
2889       unsigned Idx = 0;
2890       if (Record.size() < 4)
2891         return Error("Invalid LANDINGPAD record");
2892       Type *Ty = getTypeByID(Record[Idx++]);
2893       if (!Ty) return Error("Invalid LANDINGPAD record");
2894       Value *PersFn = 0;
2895       if (getValueTypePair(Record, Idx, NextValueNo, PersFn))
2896         return Error("Invalid LANDINGPAD record");
2897 
2898       bool IsCleanup = !!Record[Idx++];
2899       unsigned NumClauses = Record[Idx++];
2900       LandingPadInst *LP = LandingPadInst::Create(Ty, PersFn, NumClauses);
2901       LP->setCleanup(IsCleanup);
2902       for (unsigned J = 0; J != NumClauses; ++J) {
2903         LandingPadInst::ClauseType CT =
2904           LandingPadInst::ClauseType(Record[Idx++]); (void)CT;
2905         Value *Val;
2906 
2907         if (getValueTypePair(Record, Idx, NextValueNo, Val)) {
2908           delete LP;
2909           return Error("Invalid LANDINGPAD record");
2910         }
2911 
2912         assert((CT != LandingPadInst::Catch ||
2913                 !isa<ArrayType>(Val->getType())) &&
2914                "Catch clause has a invalid type!");
2915         assert((CT != LandingPadInst::Filter ||
2916                 isa<ArrayType>(Val->getType())) &&
2917                "Filter clause has invalid type!");
2918         LP->addClause(Val);
2919       }
2920 
2921       I = LP;
2922       InstructionList.push_back(I);
2923       break;
2924     }
2925 
2926     case bitc::FUNC_CODE_INST_ALLOCA: { // ALLOCA: [instty, opty, op, align]
2927       if (Record.size() != 4)
2928         return Error("Invalid ALLOCA record");
2929       PointerType *Ty =
2930         dyn_cast_or_null<PointerType>(getTypeByID(Record[0]));
2931       Type *OpTy = getTypeByID(Record[1]);
2932       Value *Size = getFnValueByID(Record[2], OpTy);
2933       unsigned Align = Record[3];
2934       if (!Ty || !Size) return Error("Invalid ALLOCA record");
2935       I = new AllocaInst(Ty->getElementType(), Size, (1 << Align) >> 1);
2936       InstructionList.push_back(I);
2937       break;
2938     }
2939     case bitc::FUNC_CODE_INST_LOAD: { // LOAD: [opty, op, align, vol]
2940       unsigned OpNum = 0;
2941       Value *Op;
2942       if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
2943           OpNum+2 != Record.size())
2944         return Error("Invalid LOAD record");
2945 
2946       I = new LoadInst(Op, "", Record[OpNum+1], (1 << Record[OpNum]) >> 1);
2947       InstructionList.push_back(I);
2948       break;
2949     }
2950     case bitc::FUNC_CODE_INST_LOADATOMIC: {
2951        // LOADATOMIC: [opty, op, align, vol, ordering, synchscope]
2952       unsigned OpNum = 0;
2953       Value *Op;
2954       if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
2955           OpNum+4 != Record.size())
2956         return Error("Invalid LOADATOMIC record");
2957 
2958 
2959       AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]);
2960       if (Ordering == NotAtomic || Ordering == Release ||
2961           Ordering == AcquireRelease)
2962         return Error("Invalid LOADATOMIC record");
2963       if (Ordering != NotAtomic && Record[OpNum] == 0)
2964         return Error("Invalid LOADATOMIC record");
2965       SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+3]);
2966 
2967       I = new LoadInst(Op, "", Record[OpNum+1], (1 << Record[OpNum]) >> 1,
2968                        Ordering, SynchScope);
2969       InstructionList.push_back(I);
2970       break;
2971     }
2972     case bitc::FUNC_CODE_INST_STORE: { // STORE2:[ptrty, ptr, val, align, vol]
2973       unsigned OpNum = 0;
2974       Value *Val, *Ptr;
2975       if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
2976           getValue(Record, OpNum,
2977                     cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
2978           OpNum+2 != Record.size())
2979         return Error("Invalid STORE record");
2980 
2981       I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1);
2982       InstructionList.push_back(I);
2983       break;
2984     }
2985     case bitc::FUNC_CODE_INST_STOREATOMIC: {
2986       // STOREATOMIC: [ptrty, ptr, val, align, vol, ordering, synchscope]
2987       unsigned OpNum = 0;
2988       Value *Val, *Ptr;
2989       if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
2990           getValue(Record, OpNum,
2991                     cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
2992           OpNum+4 != Record.size())
2993         return Error("Invalid STOREATOMIC record");
2994 
2995       AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]);
2996       if (Ordering == NotAtomic || Ordering == Acquire ||
2997           Ordering == AcquireRelease)
2998         return Error("Invalid STOREATOMIC record");
2999       SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+3]);
3000       if (Ordering != NotAtomic && Record[OpNum] == 0)
3001         return Error("Invalid STOREATOMIC record");
3002 
3003       I = new StoreInst(Val, Ptr, Record[OpNum+1], (1 << Record[OpNum]) >> 1,
3004                         Ordering, SynchScope);
3005       InstructionList.push_back(I);
3006       break;
3007     }
3008     case bitc::FUNC_CODE_INST_CMPXCHG: {
3009       // CMPXCHG:[ptrty, ptr, cmp, new, vol, ordering, synchscope]
3010       unsigned OpNum = 0;
3011       Value *Ptr, *Cmp, *New;
3012       if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
3013           getValue(Record, OpNum,
3014                     cast<PointerType>(Ptr->getType())->getElementType(), Cmp) ||
3015           getValue(Record, OpNum,
3016                     cast<PointerType>(Ptr->getType())->getElementType(), New) ||
3017           OpNum+3 != Record.size())
3018         return Error("Invalid CMPXCHG record");
3019       AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+1]);
3020       if (Ordering == NotAtomic || Ordering == Unordered)
3021         return Error("Invalid CMPXCHG record");
3022       SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+2]);
3023       I = new AtomicCmpXchgInst(Ptr, Cmp, New, Ordering, SynchScope);
3024       cast<AtomicCmpXchgInst>(I)->setVolatile(Record[OpNum]);
3025       InstructionList.push_back(I);
3026       break;
3027     }
3028     case bitc::FUNC_CODE_INST_ATOMICRMW: {
3029       // ATOMICRMW:[ptrty, ptr, val, op, vol, ordering, synchscope]
3030       unsigned OpNum = 0;
3031       Value *Ptr, *Val;
3032       if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
3033           getValue(Record, OpNum,
3034                     cast<PointerType>(Ptr->getType())->getElementType(), Val) ||
3035           OpNum+4 != Record.size())
3036         return Error("Invalid ATOMICRMW record");
3037       AtomicRMWInst::BinOp Operation = GetDecodedRMWOperation(Record[OpNum]);
3038       if (Operation < AtomicRMWInst::FIRST_BINOP ||
3039           Operation > AtomicRMWInst::LAST_BINOP)
3040         return Error("Invalid ATOMICRMW record");
3041       AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]);
3042       if (Ordering == NotAtomic || Ordering == Unordered)
3043         return Error("Invalid ATOMICRMW record");
3044       SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+3]);
3045       I = new AtomicRMWInst(Operation, Ptr, Val, Ordering, SynchScope);
3046       cast<AtomicRMWInst>(I)->setVolatile(Record[OpNum+1]);
3047       InstructionList.push_back(I);
3048       break;
3049     }
3050     case bitc::FUNC_CODE_INST_FENCE: { // FENCE:[ordering, synchscope]
3051       if (2 != Record.size())
3052         return Error("Invalid FENCE record");
3053       AtomicOrdering Ordering = GetDecodedOrdering(Record[0]);
3054       if (Ordering == NotAtomic || Ordering == Unordered ||
3055           Ordering == Monotonic)
3056         return Error("Invalid FENCE record");
3057       SynchronizationScope SynchScope = GetDecodedSynchScope(Record[1]);
3058       I = new FenceInst(Context, Ordering, SynchScope);
3059       InstructionList.push_back(I);
3060       break;
3061     }
3062     case bitc::FUNC_CODE_INST_CALL: {
3063       // CALL: [paramattrs, cc, fnty, fnid, arg0, arg1...]
3064       if (Record.size() < 3)
3065         return Error("Invalid CALL record");
3066 
3067       AttributeSet PAL = getAttributes(Record[0]);
3068       unsigned CCInfo = Record[1];
3069 
3070       unsigned OpNum = 2;
3071       Value *Callee;
3072       if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
3073         return Error("Invalid CALL record");
3074 
3075       PointerType *OpTy = dyn_cast<PointerType>(Callee->getType());
3076       FunctionType *FTy = 0;
3077       if (OpTy) FTy = dyn_cast<FunctionType>(OpTy->getElementType());
3078       if (!FTy || Record.size() < FTy->getNumParams()+OpNum)
3079         return Error("Invalid CALL record");
3080 
3081       SmallVector<Value*, 16> Args;
3082       // Read the fixed params.
3083       for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
3084         if (FTy->getParamType(i)->isLabelTy())
3085           Args.push_back(getBasicBlock(Record[OpNum]));
3086         else
3087           Args.push_back(getFnValueByID(Record[OpNum], FTy->getParamType(i)));
3088         if (Args.back() == 0) return Error("Invalid CALL record");
3089       }
3090 
3091       // Read type/value pairs for varargs params.
3092       if (!FTy->isVarArg()) {
3093         if (OpNum != Record.size())
3094           return Error("Invalid CALL record");
3095       } else {
3096         while (OpNum != Record.size()) {
3097           Value *Op;
3098           if (getValueTypePair(Record, OpNum, NextValueNo, Op))
3099             return Error("Invalid CALL record");
3100           Args.push_back(Op);
3101         }
3102       }
3103 
3104       I = CallInst::Create(Callee, Args);
3105       InstructionList.push_back(I);
3106       cast<CallInst>(I)->setCallingConv(
3107         static_cast<CallingConv::ID>(CCInfo>>1));
3108       cast<CallInst>(I)->setTailCall(CCInfo & 1);
3109       cast<CallInst>(I)->setAttributes(PAL);
3110       break;
3111     }
3112     case bitc::FUNC_CODE_INST_VAARG: { // VAARG: [valistty, valist, instty]
3113       if (Record.size() < 3)
3114         return Error("Invalid VAARG record");
3115       Type *OpTy = getTypeByID(Record[0]);
3116       Value *Op = getFnValueByID(Record[1], OpTy);
3117       Type *ResTy = getTypeByID(Record[2]);
3118       if (!OpTy || !Op || !ResTy)
3119         return Error("Invalid VAARG record");
3120       I = new VAArgInst(Op, ResTy);
3121       InstructionList.push_back(I);
3122       break;
3123     }
3124     }
3125 
3126     // Add instruction to end of current BB.  If there is no current BB, reject
3127     // this file.
3128     if (CurBB == 0) {
3129       delete I;
3130       return Error("Invalid instruction with no BB");
3131     }
3132     CurBB->getInstList().push_back(I);
3133 
3134     // If this was a terminator instruction, move to the next block.
3135     if (isa<TerminatorInst>(I)) {
3136       ++CurBBNo;
3137       CurBB = CurBBNo < FunctionBBs.size() ? FunctionBBs[CurBBNo] : 0;
3138     }
3139 
3140     // Non-void values get registered in the value table for future use.
3141     if (I && !I->getType()->isVoidTy())
3142       ValueList.AssignValue(I, NextValueNo++);
3143   }
3144 
3145   // Check the function list for unresolved values.
3146   if (Argument *A = dyn_cast<Argument>(ValueList.back())) {
3147     if (A->getParent() == 0) {
3148       // We found at least one unresolved value.  Nuke them all to avoid leaks.
3149       for (unsigned i = ModuleValueListSize, e = ValueList.size(); i != e; ++i){
3150         if ((A = dyn_cast<Argument>(ValueList[i])) && A->getParent() == 0) {
3151           A->replaceAllUsesWith(UndefValue::get(A->getType()));
3152           delete A;
3153         }
3154       }
3155       return Error("Never resolved value found in function!");
3156     }
3157   }
3158 
3159   // FIXME: Check for unresolved forward-declared metadata references
3160   // and clean up leaks.
3161 
3162   // See if anything took the address of blocks in this function.  If so,
3163   // resolve them now.
3164   DenseMap<Function*, std::vector<BlockAddrRefTy> >::iterator BAFRI =
3165     BlockAddrFwdRefs.find(F);
3166   if (BAFRI != BlockAddrFwdRefs.end()) {
3167     std::vector<BlockAddrRefTy> &RefList = BAFRI->second;
3168     for (unsigned i = 0, e = RefList.size(); i != e; ++i) {
3169       unsigned BlockIdx = RefList[i].first;
3170       if (BlockIdx >= FunctionBBs.size())
3171         return Error("Invalid blockaddress block #");
3172 
3173       GlobalVariable *FwdRef = RefList[i].second;
3174       FwdRef->replaceAllUsesWith(BlockAddress::get(F, FunctionBBs[BlockIdx]));
3175       FwdRef->eraseFromParent();
3176     }
3177 
3178     BlockAddrFwdRefs.erase(BAFRI);
3179   }
3180 
3181   // Trim the value list down to the size it was before we parsed this function.
3182   ValueList.shrinkTo(ModuleValueListSize);
3183   MDValueList.shrinkTo(ModuleMDValueListSize);
3184   std::vector<BasicBlock*>().swap(FunctionBBs);
3185   return false;
3186 }
3187 
3188 //===----------------------------------------------------------------------===//
3189 // GVMaterializer implementation
3190 //===----------------------------------------------------------------------===//
3191 
3192 
isMaterializable(const GlobalValue * GV) const3193 bool BitcodeReader::isMaterializable(const GlobalValue *GV) const {
3194   if (const Function *F = dyn_cast<Function>(GV)) {
3195     return F->isDeclaration() &&
3196       DeferredFunctionInfo.count(const_cast<Function*>(F));
3197   }
3198   return false;
3199 }
3200 
Materialize(GlobalValue * GV,std::string * ErrInfo)3201 bool BitcodeReader::Materialize(GlobalValue *GV, std::string *ErrInfo) {
3202   Function *F = dyn_cast<Function>(GV);
3203   // If it's not a function or is already material, ignore the request.
3204   if (!F || !F->isMaterializable()) return false;
3205 
3206   DenseMap<Function*, uint64_t>::iterator DFII = DeferredFunctionInfo.find(F);
3207   assert(DFII != DeferredFunctionInfo.end() && "Deferred function not found!");
3208 
3209   // Move the bit stream to the saved position of the deferred function body.
3210   Stream.JumpToBit(DFII->second);
3211 
3212   if (ParseFunctionBody(F)) {
3213     if (ErrInfo) *ErrInfo = ErrorString;
3214     return true;
3215   }
3216 
3217   // Upgrade any old intrinsic calls in the function.
3218   for (UpgradedIntrinsicMap::iterator I = UpgradedIntrinsics.begin(),
3219        E = UpgradedIntrinsics.end(); I != E; ++I) {
3220     if (I->first != I->second) {
3221       for (Value::use_iterator UI = I->first->use_begin(),
3222            UE = I->first->use_end(); UI != UE; ) {
3223         if (CallInst* CI = dyn_cast<CallInst>(*UI++))
3224           UpgradeIntrinsicCall(CI, I->second);
3225       }
3226     }
3227   }
3228 
3229   return false;
3230 }
3231 
isDematerializable(const GlobalValue * GV) const3232 bool BitcodeReader::isDematerializable(const GlobalValue *GV) const {
3233   const Function *F = dyn_cast<Function>(GV);
3234   if (!F || F->isDeclaration())
3235     return false;
3236   return DeferredFunctionInfo.count(const_cast<Function*>(F));
3237 }
3238 
Dematerialize(GlobalValue * GV)3239 void BitcodeReader::Dematerialize(GlobalValue *GV) {
3240   Function *F = dyn_cast<Function>(GV);
3241   // If this function isn't dematerializable, this is a noop.
3242   if (!F || !isDematerializable(F))
3243     return;
3244 
3245   assert(DeferredFunctionInfo.count(F) && "No info to read function later?");
3246 
3247   // Just forget the function body, we can remat it later.
3248   F->deleteBody();
3249 }
3250 
3251 
MaterializeModule(Module * M,std::string * ErrInfo)3252 bool BitcodeReader::MaterializeModule(Module *M, std::string *ErrInfo) {
3253   assert(M == TheModule &&
3254          "Can only Materialize the Module this BitcodeReader is attached to.");
3255   // Iterate over the module, deserializing any functions that are still on
3256   // disk.
3257   for (Module::iterator F = TheModule->begin(), E = TheModule->end();
3258        F != E; ++F)
3259     if (F->isMaterializable() &&
3260         Materialize(F, ErrInfo))
3261       return true;
3262 
3263   // Upgrade any intrinsic calls that slipped through (should not happen!) and
3264   // delete the old functions to clean up. We can't do this unless the entire
3265   // module is materialized because there could always be another function body
3266   // with calls to the old function.
3267   for (std::vector<std::pair<Function*, Function*> >::iterator I =
3268        UpgradedIntrinsics.begin(), E = UpgradedIntrinsics.end(); I != E; ++I) {
3269     if (I->first != I->second) {
3270       for (Value::use_iterator UI = I->first->use_begin(),
3271            UE = I->first->use_end(); UI != UE; ) {
3272         if (CallInst* CI = dyn_cast<CallInst>(*UI++))
3273           UpgradeIntrinsicCall(CI, I->second);
3274       }
3275       if (!I->first->use_empty())
3276         I->first->replaceAllUsesWith(I->second);
3277       I->first->eraseFromParent();
3278     }
3279   }
3280   std::vector<std::pair<Function*, Function*> >().swap(UpgradedIntrinsics);
3281 
3282   // Upgrade to new EH scheme. N.B. This will go away in 3.1.
3283   UpgradeExceptionHandling(M);
3284 
3285   // Check debug info intrinsics.
3286   CheckDebugInfoIntrinsics(TheModule);
3287 
3288   return false;
3289 }
3290 
InitStream()3291 bool BitcodeReader::InitStream() {
3292   if (LazyStreamer) return InitLazyStream();
3293   return InitStreamFromBuffer();
3294 }
3295 
InitStreamFromBuffer()3296 bool BitcodeReader::InitStreamFromBuffer() {
3297   const unsigned char *BufPtr = (const unsigned char*)Buffer->getBufferStart();
3298   const unsigned char *BufEnd = BufPtr+Buffer->getBufferSize();
3299 
3300   if (Buffer->getBufferSize() & 3) {
3301     if (!isRawBitcode(BufPtr, BufEnd) && !isBitcodeWrapper(BufPtr, BufEnd))
3302       return Error("Invalid bitcode signature");
3303     else
3304       return Error("Bitcode stream should be a multiple of 4 bytes in length");
3305   }
3306 
3307   // If we have a wrapper header, parse it and ignore the non-bc file contents.
3308   // The magic number is 0x0B17C0DE stored in little endian.
3309   if (isBitcodeWrapper(BufPtr, BufEnd))
3310     if (SkipBitcodeWrapperHeader(BufPtr, BufEnd, true))
3311       return Error("Invalid bitcode wrapper header");
3312 
3313   StreamFile.reset(new BitstreamReader(BufPtr, BufEnd));
3314   Stream.init(*StreamFile);
3315 
3316   return false;
3317 }
3318 
InitLazyStream()3319 bool BitcodeReader::InitLazyStream() {
3320   // Check and strip off the bitcode wrapper; BitstreamReader expects never to
3321   // see it.
3322   StreamingMemoryObject *Bytes = new StreamingMemoryObject(LazyStreamer);
3323   StreamFile.reset(new BitstreamReader(Bytes));
3324   Stream.init(*StreamFile);
3325 
3326   unsigned char buf[16];
3327   if (Bytes->readBytes(0, 16, buf) == -1)
3328     return Error("Bitcode stream must be at least 16 bytes in length");
3329 
3330   if (!isBitcode(buf, buf + 16))
3331     return Error("Invalid bitcode signature");
3332 
3333   if (isBitcodeWrapper(buf, buf + 4)) {
3334     const unsigned char *bitcodeStart = buf;
3335     const unsigned char *bitcodeEnd = buf + 16;
3336     SkipBitcodeWrapperHeader(bitcodeStart, bitcodeEnd, false);
3337     Bytes->dropLeadingBytes(bitcodeStart - buf);
3338     Bytes->setKnownObjectSize(bitcodeEnd - bitcodeStart);
3339   }
3340   return false;
3341 }
3342 
3343 //===----------------------------------------------------------------------===//
3344 // External interface
3345 //===----------------------------------------------------------------------===//
3346 
3347 /// getLazyBitcodeModule - lazy function-at-a-time loading from a file.
3348 ///
getLazyBitcodeModule(MemoryBuffer * Buffer,LLVMContext & Context,std::string * ErrMsg)3349 Module *llvm_3_0::getLazyBitcodeModule(MemoryBuffer *Buffer,
3350                                        LLVMContext& Context,
3351                                        std::string *ErrMsg) {
3352   Module *M = new Module(Buffer->getBufferIdentifier(), Context);
3353   BitcodeReader *R = new BitcodeReader(Buffer, Context);
3354   M->setMaterializer(R);
3355   if (R->ParseBitcodeInto(M)) {
3356     if (ErrMsg)
3357       *ErrMsg = R->getErrorString();
3358 
3359     delete M;  // Also deletes R.
3360     return 0;
3361   }
3362   // Have the BitcodeReader dtor delete 'Buffer'.
3363   R->setBufferOwned(true);
3364   return M;
3365 }
3366 
3367 /// ParseBitcodeFile - Read the specified bitcode file, returning the module.
3368 /// If an error occurs, return null and fill in *ErrMsg if non-null.
ParseBitcodeFile(MemoryBuffer * Buffer,LLVMContext & Context,std::string * ErrMsg)3369 Module *llvm_3_0::ParseBitcodeFile(MemoryBuffer *Buffer, LLVMContext& Context,
3370                                    std::string *ErrMsg){
3371   Module *M = llvm_3_0::getLazyBitcodeModule(Buffer, Context, ErrMsg);
3372   if (!M) return 0;
3373 
3374   // Don't let the BitcodeReader dtor delete 'Buffer', regardless of whether
3375   // there was an error.
3376   static_cast<BitcodeReader*>(M->getMaterializer())->setBufferOwned(false);
3377 
3378   // Read in the entire module, and destroy the BitcodeReader.
3379   if (M->MaterializeAllPermanently(ErrMsg)) {
3380     delete M;
3381     return 0;
3382   }
3383 
3384   return M;
3385 }
3386 
getBitcodeTargetTriple(MemoryBuffer * Buffer,LLVMContext & Context,std::string * ErrMsg)3387 std::string llvm_3_0::getBitcodeTargetTriple(MemoryBuffer *Buffer,
3388                                              LLVMContext& Context,
3389                                              std::string *ErrMsg) {
3390   BitcodeReader *R = new BitcodeReader(Buffer, Context);
3391   // Don't let the BitcodeReader dtor delete 'Buffer'.
3392   R->setBufferOwned(false);
3393 
3394   std::string Triple("");
3395   if (R->ParseTriple(Triple))
3396     if (ErrMsg)
3397       *ErrMsg = R->getErrorString();
3398 
3399   delete R;
3400   return Triple;
3401 }
3402