C++ const_global_iterator::hasInitializer方法代码示例

// run - This incorporates all types used by the specified module
//
bool FindUsedTypes::runOnModule(Module &m) {
  UsedTypes.clear();  // reset if run multiple times...

  // Loop over global variables, incorporating their types
  for (Module::const_global_iterator I = m.global_begin(), E = m.global_end();
       I != E; ++I) {
    IncorporateType(I->getType());
    if (I->hasInitializer())
      IncorporateValue(I->getInitializer());
  }

  for (Module::iterator MI = m.begin(), ME = m.end(); MI != ME; ++MI) {
    IncorporateType(MI->getType());
    const Function &F = *MI;

    // Loop over all of the instructions in the function, adding their return
    // type as well as the types of their operands.
    //
    for (const_inst_iterator II = inst_begin(F), IE = inst_end(F);
         II != IE; ++II) {
      const Instruction &I = *II;

      IncorporateType(I.getType());  // Incorporate the type of the instruction
      for (User::const_op_iterator OI = I.op_begin(), OE = I.op_end();
           OI != OE; ++OI)
        IncorporateValue(*OI);  // Insert inst operand types as well
    }
  }

  return false;
}

// linkGlobalInits - Update the initializers in the Dest module now that all
// globals that may be referenced are in Dest.
void ModuleLinker::linkGlobalInits() {
  // Loop over all of the globals in the src module, mapping them over as we go
  for (Module::const_global_iterator I = SrcM->global_begin(),
       E = SrcM->global_end(); I != E; ++I) {
    
    // Only process initialized GV's or ones not already in dest.
    if (!I->hasInitializer() || DoNotLinkFromSource.count(I)) continue;          
    
    // Grab destination global variable.
    GlobalVariable *DGV = cast<GlobalVariable>(ValueMap[I]);
    // Figure out what the initializer looks like in the dest module.
    DGV->setInitializer(MapValue(I->getInitializer(), ValueMap,
                                 RF_None, &TypeMap));
  }
}

void TypeFinder::Run(const Module &M) {

	AddModuleTypesToPrinter(TP,&M);

    // Get types from the type symbol table.  This gets opaque types referened
    // only through derived named types.
    const TypeSymbolTable &ST = M.getTypeSymbolTable();
    for (TypeSymbolTable::const_iterator TI = ST.begin(), E = ST.end();
           TI != E; ++TI)
		IncorporateType(TI->second);

    // Get types from global variables.
	for (Module::const_global_iterator I = M.global_begin(),
           E = M.global_end(); I != E; ++I) {
        IncorporateType(I->getType());
        if (I->hasInitializer())
          IncorporateValue(I->getInitializer());
    }

    // Get types from aliases.
    for (Module::const_alias_iterator I = M.alias_begin(),
         E = M.alias_end(); I != E; ++I) {
		IncorporateType(I->getType());
        IncorporateValue(I->getAliasee());
    }

    // Get types from functions.
    for (Module::const_iterator FI = M.begin(), E = M.end(); FI != E; ++FI) {
        IncorporateType(FI->getType());

		for (Function::const_iterator BB = FI->begin(), E = FI->end();
             BB != E;++BB)
			for (BasicBlock::const_iterator II = BB->begin(),
               E = BB->end(); II != E; ++II) {
				const Instruction &I = *II;
				// Incorporate the type of the instruction and all its operands.
				IncorporateType(I.getType());
				for (User::const_op_iterator OI = I.op_begin(), OE = I.op_end();
					OI != OE; ++OI)
					IncorporateValue(*OI);
			}
      }
}

ValueEnumerator::ValueEnumerator(const Module &M) {
  if (shouldPreserveBitcodeUseListOrder())
    UseListOrders = predictUseListOrder(M);

  // Enumerate the global variables.
  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
       I != E; ++I)
    EnumerateValue(I);

  // Enumerate the functions.
  for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
    EnumerateValue(I);
    EnumerateAttributes(cast<Function>(I)->getAttributes());
  }

  // Enumerate the aliases.
  for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
       I != E; ++I)
    EnumerateValue(I);

  // Remember what is the cutoff between globalvalue's and other constants.
  unsigned FirstConstant = Values.size();

  // Enumerate the global variable initializers.
  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
       I != E; ++I)
    if (I->hasInitializer())
      EnumerateValue(I->getInitializer());

  // Enumerate the aliasees.
  for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
       I != E; ++I)
    EnumerateValue(I->getAliasee());

  // Enumerate the prefix data constants.
  for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I)
    if (I->hasPrefixData())
      EnumerateValue(I->getPrefixData());

  // Insert constants and metadata that are named at module level into the slot
  // pool so that the module symbol table can refer to them...
  EnumerateValueSymbolTable(M.getValueSymbolTable());
  EnumerateNamedMetadata(M);

  SmallVector<std::pair<unsigned, MDNode *>, 8> MDs;

  // Enumerate types used by function bodies and argument lists.
  for (const Function &F : M) {
    for (const Argument &A : F.args())
      EnumerateType(A.getType());

    for (const BasicBlock &BB : F)
      for (const Instruction &I : BB) {
        for (const Use &Op : I.operands()) {
          if (MDNode *MD = dyn_cast<MDNode>(&Op))
            if (MD->isFunctionLocal() && MD->getFunction())
              // These will get enumerated during function-incorporation.
              continue;
          EnumerateOperandType(Op);
        }
        EnumerateType(I.getType());
        if (const CallInst *CI = dyn_cast<CallInst>(&I))
          EnumerateAttributes(CI->getAttributes());
        else if (const InvokeInst *II = dyn_cast<InvokeInst>(&I))
          EnumerateAttributes(II->getAttributes());

        // Enumerate metadata attached with this instruction.
        MDs.clear();
        I.getAllMetadataOtherThanDebugLoc(MDs);
        for (unsigned i = 0, e = MDs.size(); i != e; ++i)
          EnumerateMetadata(MDs[i].second);

        if (!I.getDebugLoc().isUnknown()) {
          MDNode *Scope, *IA;
          I.getDebugLoc().getScopeAndInlinedAt(Scope, IA, I.getContext());
          if (Scope) EnumerateMetadata(Scope);
          if (IA) EnumerateMetadata(IA);
        }
      }
  }

  // Optimize constant ordering.
  OptimizeConstants(FirstConstant, Values.size());
}

std::unique_ptr<Module> llvm::CloneModule(
    const Module *M, ValueToValueMapTy &VMap,
    std::function<bool(const GlobalValue *)> ShouldCloneDefinition) {
  // First off, we need to create the new module.
  std::unique_ptr<Module> New =
      llvm::make_unique<Module>(M->getModuleIdentifier(), M->getContext());
  New->setDataLayout(M->getDataLayout());
  New->setTargetTriple(M->getTargetTriple());
  New->setModuleInlineAsm(M->getModuleInlineAsm());
   
  // Loop over all of the global variables, making corresponding globals in the
  // new module.  Here we add them to the VMap and to the new Module.  We
  // don't worry about attributes or initializers, they will come later.
  //
  for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
       I != E; ++I) {
    GlobalVariable *GV = new GlobalVariable(*New, 
                                            I->getValueType(),
                                            I->isConstant(), I->getLinkage(),
                                            (Constant*) nullptr, I->getName(),
                                            (GlobalVariable*) nullptr,
                                            I->getThreadLocalMode(),
                                            I->getType()->getAddressSpace());
    GV->copyAttributesFrom(&*I);
    VMap[&*I] = GV;
  }

  // Loop over the functions in the module, making external functions as before
  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
    Function *NF =
        Function::Create(cast<FunctionType>(I->getValueType()),
                         I->getLinkage(), I->getName(), New.get());
    NF->copyAttributesFrom(&*I);
    VMap[&*I] = NF;
  }

  // Loop over the aliases in the module
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I) {
    if (!ShouldCloneDefinition(&*I)) {
      // An alias cannot act as an external reference, so we need to create
      // either a function or a global variable depending on the value type.
      // FIXME: Once pointee types are gone we can probably pick one or the
      // other.
      GlobalValue *GV;
      if (I->getValueType()->isFunctionTy())
        GV = Function::Create(cast<FunctionType>(I->getValueType()),
                              GlobalValue::ExternalLinkage, I->getName(),
                              New.get());
      else
        GV = new GlobalVariable(
            *New, I->getValueType(), false, GlobalValue::ExternalLinkage,
            (Constant *)nullptr, I->getName(), (GlobalVariable *)nullptr,
            I->getThreadLocalMode(), I->getType()->getAddressSpace());
      VMap[&*I] = GV;
      // We do not copy attributes (mainly because copying between different
      // kinds of globals is forbidden), but this is generally not required for
      // correctness.
      continue;
    }
    auto *GA = GlobalAlias::create(I->getValueType(),
                                   I->getType()->getPointerAddressSpace(),
                                   I->getLinkage(), I->getName(), New.get());
    GA->copyAttributesFrom(&*I);
    VMap[&*I] = GA;
  }
  
  // Now that all of the things that global variable initializer can refer to
  // have been created, loop through and copy the global variable referrers
  // over...  We also set the attributes on the global now.
  //
  for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
       I != E; ++I) {
    GlobalVariable *GV = cast<GlobalVariable>(VMap[&*I]);
    if (!ShouldCloneDefinition(&*I)) {
      // Skip after setting the correct linkage for an external reference.
      GV->setLinkage(GlobalValue::ExternalLinkage);
      continue;
    }
    if (I->hasInitializer())
      GV->setInitializer(MapValue(I->getInitializer(), VMap));
  }

  // Similarly, copy over function bodies now...
  //
  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
    Function *F = cast<Function>(VMap[&*I]);
    if (!ShouldCloneDefinition(&*I)) {
      // Skip after setting the correct linkage for an external reference.
      F->setLinkage(GlobalValue::ExternalLinkage);
      // Personality function is not valid on a declaration.
      F->setPersonalityFn(nullptr);
      continue;
    }
    if (!I->isDeclaration()) {
      Function::arg_iterator DestI = F->arg_begin();
      for (Function::const_arg_iterator J = I->arg_begin(); J != I->arg_end();
           ++J) {
        DestI->setName(J->getName());
        VMap[&*J] = &*DestI++;
//.........这里部分代码省略.........

void TypeFinder::run(const Module &M, bool onlyNamed) {
    OnlyNamed = onlyNamed;

    // Get types from global variables.
    for (Module::const_global_iterator I = M.global_begin(),
            E = M.global_end(); I != E; ++I) {
        incorporateType(I->getType());
        if (I->hasInitializer())
            incorporateValue(I->getInitializer());
    }

    // Get types from aliases.
    for (Module::const_alias_iterator I = M.alias_begin(),
            E = M.alias_end(); I != E; ++I) {
        incorporateType(I->getType());
        if (const Value *Aliasee = I->getAliasee())
            incorporateValue(Aliasee);
    }

    // Get types from functions.
    SmallVector<std::pair<unsigned, MDNode *>, 4> MDForInst;
    for (Module::const_iterator FI = M.begin(), E = M.end(); FI != E; ++FI) {
        incorporateType(FI->getType());

        if (FI->hasPrefixData())
            incorporateValue(FI->getPrefixData());

        if (FI->hasPrologueData())
            incorporateValue(FI->getPrologueData());

        if (FI->hasPersonalityFn())
            incorporateValue(FI->getPersonalityFn());

        // First incorporate the arguments.
        for (Function::const_arg_iterator AI = FI->arg_begin(),
                AE = FI->arg_end(); AI != AE; ++AI)
            incorporateValue(AI);

        for (Function::const_iterator BB = FI->begin(), E = FI->end();
                BB != E; ++BB)
            for (BasicBlock::const_iterator II = BB->begin(),
                    E = BB->end(); II != E; ++II) {
                const Instruction &I = *II;

                // Incorporate the type of the instruction.
                incorporateType(I.getType());

                // Incorporate non-instruction operand types. (We are incorporating all
                // instructions with this loop.)
                for (User::const_op_iterator OI = I.op_begin(), OE = I.op_end();
                        OI != OE; ++OI)
                    if (*OI && !isa<Instruction>(OI))
                        incorporateValue(*OI);

                // Incorporate types hiding in metadata.
                I.getAllMetadataOtherThanDebugLoc(MDForInst);
                for (unsigned i = 0, e = MDForInst.size(); i != e; ++i)
                    incorporateMDNode(MDForInst[i].second);

                MDForInst.clear();
            }
    }

    for (Module::const_named_metadata_iterator I = M.named_metadata_begin(),
            E = M.named_metadata_end(); I != E; ++I) {
        const NamedMDNode *NMD = I;
        for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i)
            incorporateMDNode(NMD->getOperand(i));
    }
}

bool SparcAsmPrinter::doFinalization(Module &M) {
  const TargetData *TD = TM.getTargetData();

  // Print out module-level global variables here.
  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
       I != E; ++I)
    if (I->hasInitializer()) {   // External global require no code
      // Check to see if this is a special global used by LLVM, if so, emit it.
      if (EmitSpecialLLVMGlobal(I))
        continue;
      
      O << "\n\n";
      std::string name = Mang->getValueName(I);
      Constant *C = I->getInitializer();
      unsigned Size = TD->getABITypeSize(C->getType());
      unsigned Align = TD->getPreferredAlignment(I);

      if (C->isNullValue() &&
          (I->hasLinkOnceLinkage() || I->hasInternalLinkage() ||
           I->hasWeakLinkage() /* FIXME: Verify correct */)) {
        SwitchToDataSection(".data", I);
        if (I->hasInternalLinkage())
          O << "\t.local " << name << "\n";

        O << "\t.comm " << name << "," << TD->getABITypeSize(C->getType())
          << "," << Align;
        O << "\n";
      } else {
        switch (I->getLinkage()) {
        case GlobalValue::LinkOnceLinkage:
        case GlobalValue::WeakLinkage:   // FIXME: Verify correct for weak.
          // Nonnull linkonce -> weak
          O << "\t.weak " << name << "\n";
          SwitchToDataSection("", I);
          O << "\t.section\t\".llvm.linkonce.d." << name
            << "\",\"aw\",@progbits\n";
          break;

        case GlobalValue::AppendingLinkage:
          // FIXME: appending linkage variables should go into a section of
          // their name or something.  For now, just emit them as external.
        case GlobalValue::ExternalLinkage:
          // If external or appending, declare as a global symbol
          O << "\t.globl " << name << "\n";
          // FALL THROUGH
        case GlobalValue::InternalLinkage:
          if (C->isNullValue())
            SwitchToDataSection(".bss", I);
          else
            SwitchToDataSection(".data", I);
          break;
        case GlobalValue::GhostLinkage:
          cerr << "Should not have any unmaterialized functions!\n";
          abort();
        case GlobalValue::DLLImportLinkage:
          cerr << "DLLImport linkage is not supported by this target!\n";
          abort();
        case GlobalValue::DLLExportLinkage:
          cerr << "DLLExport linkage is not supported by this target!\n";
          abort();
        default:
          assert(0 && "Unknown linkage type!");          
        }

        O << "\t.align " << Align << "\n";
        O << "\t.type " << name << ",#object\n";
        O << "\t.size " << name << "," << Size << "\n";
        O << name << ":\n";
        EmitGlobalConstant(C);
      }
    }

  return AsmPrinter::doFinalization(M);
}

Module *llvm::CloneModule(const Module *M, ValueToValueMapTy &VMap) {
  // First off, we need to create the new module.
  Module *New = new Module(M->getModuleIdentifier(), M->getContext());
  New->setDataLayout(M->getDataLayout());
  New->setTargetTriple(M->getTargetTriple());
  New->setModuleInlineAsm(M->getModuleInlineAsm());
   
  // Loop over all of the global variables, making corresponding globals in the
  // new module.  Here we add them to the VMap and to the new Module.  We
  // don't worry about attributes or initializers, they will come later.
  //
  for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
       I != E; ++I) {
    GlobalVariable *GV = new GlobalVariable(*New, 
                                            I->getType()->getElementType(),
                                            I->isConstant(), I->getLinkage(),
                                            (Constant*) nullptr, I->getName(),
                                            (GlobalVariable*) nullptr,
                                            I->getThreadLocalMode(),
                                            I->getType()->getAddressSpace());
    GV->copyAttributesFrom(I);
    VMap[I] = GV;
  }

  // Loop over the functions in the module, making external functions as before
  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
    Function *NF =
      Function::Create(cast<FunctionType>(I->getType()->getElementType()),
                       I->getLinkage(), I->getName(), New);
    NF->copyAttributesFrom(I);
    VMap[I] = NF;
  }

  // Loop over the aliases in the module
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I) {
    auto *PTy = cast<PointerType>(I->getType());
    auto *GA =
        GlobalAlias::create(PTy->getElementType(), PTy->getAddressSpace(),
                            I->getLinkage(), I->getName(), New);
    GA->copyAttributesFrom(I);
    VMap[I] = GA;
  }
  
  // Now that all of the things that global variable initializer can refer to
  // have been created, loop through and copy the global variable referrers
  // over...  We also set the attributes on the global now.
  //
  for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
       I != E; ++I) {
    GlobalVariable *GV = cast<GlobalVariable>(VMap[I]);
    if (I->hasInitializer())
      GV->setInitializer(MapValue(I->getInitializer(), VMap));
  }

  // Similarly, copy over function bodies now...
  //
  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
    Function *F = cast<Function>(VMap[I]);
    if (!I->isDeclaration()) {
      Function::arg_iterator DestI = F->arg_begin();
      for (Function::const_arg_iterator J = I->arg_begin(); J != I->arg_end();
           ++J) {
        DestI->setName(J->getName());
        VMap[J] = DestI++;
      }

      SmallVector<ReturnInst*, 8> Returns;  // Ignore returns cloned.
      CloneFunctionInto(F, I, VMap, /*ModuleLevelChanges=*/true, Returns);
    }
  }

  // And aliases
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I) {
    GlobalAlias *GA = cast<GlobalAlias>(VMap[I]);
    if (const Constant *C = I->getAliasee())
      GA->setAliasee(cast<GlobalObject>(MapValue(C, VMap)));
  }

  // And named metadata....
  for (Module::const_named_metadata_iterator I = M->named_metadata_begin(),
         E = M->named_metadata_end(); I != E; ++I) {
    const NamedMDNode &NMD = *I;
    NamedMDNode *NewNMD = New->getOrInsertNamedMetadata(NMD.getName());
    for (unsigned i = 0, e = NMD.getNumOperands(); i != e; ++i)
      NewNMD->addOperand(MapValue(NMD.getOperand(i), VMap));
  }

  return New;
}

/// ValueEnumerator - Enumerate module-level information.
ValueEnumerator::ValueEnumerator(const Module *M) {
  // Enumerate the global variables.
  for (Module::const_global_iterator I = M->global_begin(),
         E = M->global_end(); I != E; ++I)
    EnumerateValue(I);

  // Enumerate the functions.
  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
    EnumerateValue(I);
    EnumerateAttributes(cast<Function>(I)->getAttributes());
  }

  // Enumerate the aliases.
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I)
    EnumerateValue(I);

  // Remember what is the cutoff between globalvalue's and other constants.
  unsigned FirstConstant = Values.size();

  // Enumerate the global variable initializers.
  for (Module::const_global_iterator I = M->global_begin(),
         E = M->global_end(); I != E; ++I)
    if (I->hasInitializer())
      EnumerateValue(I->getInitializer());

  // Enumerate the aliasees.
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I)
    EnumerateValue(I->getAliasee());

  // Insert constants and metadata that are named at module level into the slot
  // pool so that the module symbol table can refer to them...
  EnumerateValueSymbolTable(M->getValueSymbolTable());
  EnumerateNamedMetadata(M);

  SmallVector<std::pair<unsigned, MDNode*>, 8> MDs;

  // Enumerate types used by function bodies and argument lists.
  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {

    for (Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end();
         I != E; ++I)
      EnumerateType(I->getType());

    for (Function::const_iterator BB = F->begin(), E = F->end(); BB != E; ++BB)
      for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I!=E;++I){
        for (User::const_op_iterator OI = I->op_begin(), E = I->op_end();
             OI != E; ++OI) {
          if (MDNode *MD = dyn_cast<MDNode>(*OI))
            if (MD->isFunctionLocal() && MD->getFunction())
              // These will get enumerated during function-incorporation.
              continue;
          EnumerateOperandType(*OI);
        }
        EnumerateType(I->getType());
        if (const CallInst *CI = dyn_cast<CallInst>(I))
          EnumerateAttributes(CI->getAttributes());
        else if (const InvokeInst *II = dyn_cast<InvokeInst>(I))
          EnumerateAttributes(II->getAttributes());

        // Enumerate metadata attached with this instruction.
        MDs.clear();
        I->getAllMetadataOtherThanDebugLoc(MDs);
        for (unsigned i = 0, e = MDs.size(); i != e; ++i)
          EnumerateMetadata(MDs[i].second);

        if (!I->getDebugLoc().isUnknown()) {
          MDNode *Scope, *IA;
          I->getDebugLoc().getScopeAndInlinedAt(Scope, IA, I->getContext());
          if (Scope) EnumerateMetadata(Scope);
          if (IA) EnumerateMetadata(IA);
        }
      }
  }

  // Optimize constant ordering.
  OptimizeConstants(FirstConstant, Values.size());
}

ValueEnumerator::ValueEnumerator(const Module &M,
                                 bool ShouldPreserveUseListOrder)
    : HasMDString(false), HasDILocation(false), HasGenericDINode(false),
      ShouldPreserveUseListOrder(ShouldPreserveUseListOrder) {
  if (ShouldPreserveUseListOrder)
    UseListOrders = predictUseListOrder(M);

  // Enumerate the global variables.
  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
       I != E; ++I)
    EnumerateValue(I);

  // Enumerate the functions.
  for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
    EnumerateValue(I);
    EnumerateAttributes(cast<Function>(I)->getAttributes());
  }

  // Enumerate the aliases.
  for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
       I != E; ++I)
    EnumerateValue(I);

  // Remember what is the cutoff between globalvalue's and other constants.
  unsigned FirstConstant = Values.size();

  // Enumerate the global variable initializers.
  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
       I != E; ++I)
    if (I->hasInitializer())
      EnumerateValue(I->getInitializer());

  // Enumerate the aliasees.
  for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
       I != E; ++I)
    EnumerateValue(I->getAliasee());

  // Enumerate the prefix data constants.
  for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I)
    if (I->hasPrefixData())
      EnumerateValue(I->getPrefixData());

  // Enumerate the prologue data constants.
  for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I)
    if (I->hasPrologueData())
      EnumerateValue(I->getPrologueData());

  // Enumerate the metadata type.
  //
  // TODO: Move this to ValueEnumerator::EnumerateOperandType() once bitcode
  // only encodes the metadata type when it's used as a value.
  EnumerateType(Type::getMetadataTy(M.getContext()));

  // Insert constants and metadata that are named at module level into the slot
  // pool so that the module symbol table can refer to them...
  EnumerateValueSymbolTable(M.getValueSymbolTable());
  EnumerateNamedMetadata(M);

  SmallVector<std::pair<unsigned, MDNode *>, 8> MDs;

  // Enumerate types used by function bodies and argument lists.
  for (const Function &F : M) {
    for (const Argument &A : F.args())
      EnumerateType(A.getType());

    // Enumerate metadata attached to this function.
    F.getAllMetadata(MDs);
    for (const auto &I : MDs)
      EnumerateMetadata(I.second);

    for (const BasicBlock &BB : F)
      for (const Instruction &I : BB) {
        for (const Use &Op : I.operands()) {
          auto *MD = dyn_cast<MetadataAsValue>(&Op);
          if (!MD) {
            EnumerateOperandType(Op);
            continue;
          }

          // Local metadata is enumerated during function-incorporation.
          if (isa<LocalAsMetadata>(MD->getMetadata()))
            continue;

          EnumerateMetadata(MD->getMetadata());
        }
        EnumerateType(I.getType());
        if (const CallInst *CI = dyn_cast<CallInst>(&I))
          EnumerateAttributes(CI->getAttributes());
        else if (const InvokeInst *II = dyn_cast<InvokeInst>(&I))
          EnumerateAttributes(II->getAttributes());

        // Enumerate metadata attached with this instruction.
        MDs.clear();
        I.getAllMetadataOtherThanDebugLoc(MDs);
        for (unsigned i = 0, e = MDs.size(); i != e; ++i)
          EnumerateMetadata(MDs[i].second);

        // Don't enumerate the location directly -- it has a special record
        // type -- but enumerate its operands.
        if (DILocation *L = I.getDebugLoc())
//.........这里部分代码省略.........

/// NaClValueEnumerator - Enumerate module-level information.
NaClValueEnumerator::NaClValueEnumerator(const Module *M) {
  // Create map for counting frequency of types, and set field
  // TypeCountMap accordingly.  Note: Pointer field TypeCountMap is
  // used to deal with the fact that types are added through various
  // method calls in this routine. Rather than pass it as an argument,
  // we use a field. The field is a pointer so that the memory
  // footprint of count_map can be garbage collected when this
  // constructor completes.
  TypeCountMapType count_map;
  TypeCountMap = &count_map;
  // Enumerate the global variables.
  for (Module::const_global_iterator I = M->global_begin(),
         E = M->global_end(); I != E; ++I)
    EnumerateValue(I);

  // Enumerate the functions.
  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
    EnumerateValue(I);
    EnumerateAttributes(cast<Function>(I)->getAttributes());
  }

  // Enumerate the aliases.
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I)
    EnumerateValue(I);

  // Remember what is the cutoff between globalvalue's and other constants.
  unsigned FirstConstant = Values.size();

  // Enumerate the global variable initializers.
  for (Module::const_global_iterator I = M->global_begin(),
         E = M->global_end(); I != E; ++I)
    if (I->hasInitializer())
      EnumerateValue(I->getInitializer());

  // Enumerate the aliasees.
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I)
    EnumerateValue(I->getAliasee());

  // Insert constants and metadata that are named at module level into the slot
  // pool so that the module symbol table can refer to them...
  EnumerateValueSymbolTable(M->getValueSymbolTable());
  EnumerateNamedMetadata(M);

  SmallVector<std::pair<unsigned, MDNode*>, 8> MDs;

  // Enumerate types used by function bodies and argument lists.
  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {

    for (Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end();
         I != E; ++I)
      EnumerateType(I->getType());

    for (Function::const_iterator BB = F->begin(), E = F->end(); BB != E; ++BB)
      for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I!=E;++I){
        for (User::const_op_iterator OI = I->op_begin(), E = I->op_end();
             OI != E; ++OI) {
          if (MDNode *MD = dyn_cast<MDNode>(*OI))
            if (MD->isFunctionLocal() && MD->getFunction())
              // These will get enumerated during function-incorporation.
              continue;
          EnumerateOperandType(*OI);
        }
        EnumerateType(I->getType());
        if (const CallInst *CI = dyn_cast<CallInst>(I))
          EnumerateAttributes(CI->getAttributes());
        else if (const InvokeInst *II = dyn_cast<InvokeInst>(I))
          EnumerateAttributes(II->getAttributes());

        // Enumerate metadata attached with this instruction.
        MDs.clear();
        I->getAllMetadataOtherThanDebugLoc(MDs);
        for (unsigned i = 0, e = MDs.size(); i != e; ++i)
          EnumerateMetadata(MDs[i].second);

        if (!I->getDebugLoc().isUnknown()) {
          MDNode *Scope, *IA;
          I->getDebugLoc().getScopeAndInlinedAt(Scope, IA, I->getContext());
          if (Scope) EnumerateMetadata(Scope);
          if (IA) EnumerateMetadata(IA);
        }
      }
  }

  // Optimized type indicies to put "common" expected types in with small
  // indices.
  OptimizeTypes(M);
  TypeCountMap = NULL;

  // Optimize constant ordering.
  OptimizeConstants(FirstConstant, Values.size());
}

Module *llvm::CloneModule(const Module *M,
                          DenseMap<const Value*, Value*> &ValueMap) {
  // First off, we need to create the new module...
  Module *New = new Module(M->getModuleIdentifier());
  New->setDataLayout(M->getDataLayout());
  New->setTargetTriple(M->getTargetTriple());
  New->setModuleInlineAsm(M->getModuleInlineAsm());

  // Copy all of the type symbol table entries over.
  const TypeSymbolTable &TST = M->getTypeSymbolTable();
  for (TypeSymbolTable::const_iterator TI = TST.begin(), TE = TST.end(); 
       TI != TE; ++TI)
    New->addTypeName(TI->first, TI->second);
  
  // Copy all of the dependent libraries over.
  for (Module::lib_iterator I = M->lib_begin(), E = M->lib_end(); I != E; ++I)
    New->addLibrary(*I);

  // Loop over all of the global variables, making corresponding globals in the
  // new module.  Here we add them to the ValueMap and to the new Module.  We
  // don't worry about attributes or initializers, they will come later.
  //
  for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
       I != E; ++I) {
    GlobalVariable *GV = new GlobalVariable(I->getType()->getElementType(),
                                            false,
                                            GlobalValue::ExternalLinkage, 0,
                                            I->getName(), New);
    GV->setAlignment(I->getAlignment());
    ValueMap[I] = GV;
  }

  // Loop over the functions in the module, making external functions as before
  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
    Function *NF =
      Function::Create(cast<FunctionType>(I->getType()->getElementType()),
                       GlobalValue::ExternalLinkage, I->getName(), New);
    NF->copyAttributesFrom(I);
    ValueMap[I] = NF;
  }

  // Loop over the aliases in the module
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I)
    ValueMap[I] = new GlobalAlias(I->getType(), GlobalAlias::ExternalLinkage,
                                  I->getName(), NULL, New);
  
  // Now that all of the things that global variable initializer can refer to
  // have been created, loop through and copy the global variable referrers
  // over...  We also set the attributes on the global now.
  //
  for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
       I != E; ++I) {
    GlobalVariable *GV = cast<GlobalVariable>(ValueMap[I]);
    if (I->hasInitializer())
      GV->setInitializer(cast<Constant>(MapValue(I->getInitializer(),
                                                 ValueMap)));
    GV->setLinkage(I->getLinkage());
    GV->setThreadLocal(I->isThreadLocal());
    GV->setConstant(I->isConstant());
  }

  // Similarly, copy over function bodies now...
  //
  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
    Function *F = cast<Function>(ValueMap[I]);
    if (!I->isDeclaration()) {
      Function::arg_iterator DestI = F->arg_begin();
      for (Function::const_arg_iterator J = I->arg_begin(); J != I->arg_end();
           ++J) {
        DestI->setName(J->getName());
        ValueMap[J] = DestI++;
      }

      std::vector<ReturnInst*> Returns;  // Ignore returns cloned...
      CloneFunctionInto(F, I, ValueMap, Returns);
    }

    F->setLinkage(I->getLinkage());
  }

  // And aliases
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I) {
    GlobalAlias *GA = cast<GlobalAlias>(ValueMap[I]);
    GA->setLinkage(I->getLinkage());
    if (const Constant* C = I->getAliasee())
      GA->setAliasee(cast<Constant>(MapValue(C, ValueMap)));
  }
  
  return New;
}

/// ValueEnumerator - Enumerate module-level information.
ValueEnumerator::ValueEnumerator(const Module *M) {
  InstructionCount = 0;

  // Enumerate the global variables.
  for (Module::const_global_iterator I = M->global_begin(),
         E = M->global_end(); I != E; ++I)
    EnumerateValue(I);

  // Enumerate the functions.
  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
    EnumerateValue(I);
    EnumerateAttributes(cast<Function>(I)->getAttributes());
  }

  // Enumerate the aliases.
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I)
    EnumerateValue(I);

  // Remember what is the cutoff between globalvalue's and other constants.
  unsigned FirstConstant = Values.size();

  // Enumerate the global variable initializers.
  for (Module::const_global_iterator I = M->global_begin(),
         E = M->global_end(); I != E; ++I)
    if (I->hasInitializer())
      EnumerateValue(I->getInitializer());

  // Enumerate the aliasees.
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I)
    EnumerateValue(I->getAliasee());

  // Enumerate types used by the type symbol table.
  EnumerateTypeSymbolTable(M->getTypeSymbolTable());

  // Insert constants that are named at module level into the slot pool so that
  // the module symbol table can refer to them...
  EnumerateValueSymbolTable(M->getValueSymbolTable());

  // Enumerate types used by function bodies and argument lists.
  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {

    for (Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end();
         I != E; ++I)
      EnumerateType(I->getType());

    MetadataContext &TheMetadata = F->getContext().getMetadata();
    typedef SmallVector<std::pair<unsigned, TrackingVH<MDNode> >, 2> MDMapTy;
    MDMapTy MDs;
    for (Function::const_iterator BB = F->begin(), E = F->end(); BB != E; ++BB)
      for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I!=E;++I){
        for (User::const_op_iterator OI = I->op_begin(), E = I->op_end();
             OI != E; ++OI)
          EnumerateOperandType(*OI);
        EnumerateType(I->getType());
        if (const CallInst *CI = dyn_cast<CallInst>(I))
          EnumerateAttributes(CI->getAttributes());
        else if (const InvokeInst *II = dyn_cast<InvokeInst>(I))
          EnumerateAttributes(II->getAttributes());

        // Enumerate metadata attached with this instruction.
        MDs.clear();
        TheMetadata.getMDs(I, MDs);
        for (MDMapTy::const_iterator MI = MDs.begin(), ME = MDs.end(); MI != ME;
             ++MI)
          EnumerateMetadata(MI->second);
      }
  }

  // Optimize constant ordering.
  OptimizeConstants(FirstConstant, Values.size());

  // Sort the type table by frequency so that most commonly used types are early
  // in the table (have low bit-width).
  std::stable_sort(Types.begin(), Types.end(), CompareByFrequency);

  // Partition the Type ID's so that the single-value types occur before the
  // aggregate types.  This allows the aggregate types to be dropped from the
  // type table after parsing the global variable initializers.
  std::partition(Types.begin(), Types.end(), isSingleValueType);

  // Now that we rearranged the type table, rebuild TypeMap.
  for (unsigned i = 0, e = Types.size(); i != e; ++i)
    TypeMap[Types[i].first] = i+1;
}

Module *llvm::CloneModule(const Module *M,
                          ValueToValueMapTy &VMap) {
  // First off, we need to create the new module...
  Module *New = new Module(M->getModuleIdentifier(), M->getContext());
  New->setDataLayout(M->getDataLayout());
  New->setTargetTriple(M->getTargetTriple());
  New->setModuleInlineAsm(M->getModuleInlineAsm());

  // Copy all of the type symbol table entries over.
  const TypeSymbolTable &TST = M->getTypeSymbolTable();
  for (TypeSymbolTable::const_iterator TI = TST.begin(), TE = TST.end(); 
       TI != TE; ++TI)
    New->addTypeName(TI->first, TI->second);
  
  // Copy all of the dependent libraries over.
  for (Module::lib_iterator I = M->lib_begin(), E = M->lib_end(); I != E; ++I)
    New->addLibrary(*I);

  // Loop over all of the global variables, making corresponding globals in the
  // new module.  Here we add them to the VMap and to the new Module.  We
  // don't worry about attributes or initializers, they will come later.
  //
  for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
       I != E; ++I) {
    GlobalVariable *GV = new GlobalVariable(*New, 
                                            I->getType()->getElementType(),
                                            false,
                                            GlobalValue::ExternalLinkage, 0,
                                            I->getName());
    GV->setAlignment(I->getAlignment());
    VMap[I] = GV;
  }

  // Loop over the functions in the module, making external functions as before
  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
    Function *NF =
      Function::Create(cast<FunctionType>(I->getType()->getElementType()),
                       GlobalValue::ExternalLinkage, I->getName(), New);
    NF->copyAttributesFrom(I);
    VMap[I] = NF;
  }

  // Loop over the aliases in the module
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I)
    VMap[I] = new GlobalAlias(I->getType(), GlobalAlias::ExternalLinkage,
                                  I->getName(), NULL, New);
  
  // Now that all of the things that global variable initializer can refer to
  // have been created, loop through and copy the global variable referrers
  // over...  We also set the attributes on the global now.
  //
  for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
       I != E; ++I) {
    GlobalVariable *GV = cast<GlobalVariable>(VMap[I]);
    if (I->hasInitializer())
      GV->setInitializer(cast<Constant>(MapValue(I->getInitializer(),
                                                 VMap)));
    GV->setLinkage(I->getLinkage());
    GV->setThreadLocal(I->isThreadLocal());
    GV->setConstant(I->isConstant());
  }

  // Similarly, copy over function bodies now...
  //
  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
    Function *F = cast<Function>(VMap[I]);
    if (!I->isDeclaration()) {
      Function::arg_iterator DestI = F->arg_begin();
      for (Function::const_arg_iterator J = I->arg_begin(); J != I->arg_end();
           ++J) {
        DestI->setName(J->getName());
        VMap[J] = DestI++;
      }

      SmallVector<ReturnInst*, 8> Returns;  // Ignore returns cloned.
      CloneFunctionInto(F, I, VMap, Returns);
    }

    F->setLinkage(I->getLinkage());
  }

  // And aliases
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I) {
    GlobalAlias *GA = cast<GlobalAlias>(VMap[I]);
    GA->setLinkage(I->getLinkage());
    if (const Constant* C = I->getAliasee())
      GA->setAliasee(cast<Constant>(MapValue(C, VMap)));
  }

  // And named metadata....
  for (Module::const_named_metadata_iterator I = M->named_metadata_begin(),
         E = M->named_metadata_end(); I != E; ++I) {
    const NamedMDNode &NMD = *I;
    SmallVector<MDNode*, 4> MDs;
    for (unsigned i = 0, e = NMD.getNumOperands(); i != e; ++i)
      MDs.push_back(cast<MDNode>(MapValue(NMD.getOperand(i), VMap)));
    NamedMDNode::Create(New->getContext(), NMD.getName(),
                        MDs.data(), MDs.size(), New);
//.........这里部分代码省略.........

/// ValueEnumerator - Enumerate module-level information.
ValueEnumerator::ValueEnumerator(const Module *M) {
  // Enumerate the global variables.
  for (Module::const_global_iterator I = M->global_begin(),
         E = M->global_end(); I != E; ++I)
    EnumerateValue(I);

  // Enumerate the functions.
  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
    EnumerateValue(I);
    EnumerateParamAttrs(cast<Function>(I)->getParamAttrs());
  }

  // Enumerate the aliases.
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I)
    EnumerateValue(I);
  
  // Remember what is the cutoff between globalvalue's and other constants.
  unsigned FirstConstant = Values.size();
  
  // Enumerate the global variable initializers.
  for (Module::const_global_iterator I = M->global_begin(),
         E = M->global_end(); I != E; ++I)
    if (I->hasInitializer())
      EnumerateValue(I->getInitializer());

  // Enumerate the aliasees.
  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
       I != E; ++I)
    EnumerateValue(I->getAliasee());
  
  // Enumerate types used by the type symbol table.
  EnumerateTypeSymbolTable(M->getTypeSymbolTable());

  // Insert constants that are named at module level into the slot pool so that
  // the module symbol table can refer to them...
  EnumerateValueSymbolTable(M->getValueSymbolTable());
  
  // Enumerate types used by function bodies and argument lists.
  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
    
    for (Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end();
         I != E; ++I)
      EnumerateType(I->getType());
    
    for (Function::const_iterator BB = F->begin(), E = F->end(); BB != E; ++BB)
      for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I!=E;++I){
        for (User::const_op_iterator OI = I->op_begin(), E = I->op_end(); 
             OI != E; ++OI)
          EnumerateOperandType(*OI);
        EnumerateType(I->getType());
        if (const CallInst *CI = dyn_cast<CallInst>(I))
          EnumerateParamAttrs(CI->getParamAttrs());
        else if (const InvokeInst *II = dyn_cast<InvokeInst>(I))
          EnumerateParamAttrs(II->getParamAttrs());
      }
  }
  
  // Optimize constant ordering.
  OptimizeConstants(FirstConstant, Values.size());
    
  // Sort the type table by frequency so that most commonly used types are early
  // in the table (have low bit-width).
  std::stable_sort(Types.begin(), Types.end(), CompareByFrequency);
    
  // Partition the Type ID's so that the first-class types occur before the
  // aggregate types.  This allows the aggregate types to be dropped from the
  // type table after parsing the global variable initializers.
  std::partition(Types.begin(), Types.end(), isFirstClassType);

  // Now that we rearranged the type table, rebuild TypeMap.
  for (unsigned i = 0, e = Types.size(); i != e; ++i)
    TypeMap[Types[i].first] = i+1;
}