C++ CodeGenFunction::EmitAggExpr方法代码示例

static void EmitDeclInit(CodeGenFunction &CGF, const VarDecl &D,
                         ConstantAddress DeclPtr) {
  assert(D.hasGlobalStorage() && "VarDecl must have global storage!");
  assert(!D.getType()->isReferenceType() && 
         "Should not call EmitDeclInit on a reference!");
  
  QualType type = D.getType();
  LValue lv = CGF.MakeAddrLValue(DeclPtr, type);

  const Expr *Init = D.getInit();
  switch (CGF.getEvaluationKind(type)) {
  case TEK_Scalar: {
    CodeGenModule &CGM = CGF.CGM;
    if (lv.isObjCStrong())
      CGM.getObjCRuntime().EmitObjCGlobalAssign(CGF, CGF.EmitScalarExpr(Init),
                                                DeclPtr, D.getTLSKind());
    else if (lv.isObjCWeak())
      CGM.getObjCRuntime().EmitObjCWeakAssign(CGF, CGF.EmitScalarExpr(Init),
                                              DeclPtr);
    else
      CGF.EmitScalarInit(Init, &D, lv, false);
    return;
  }
  case TEK_Complex:
    CGF.EmitComplexExprIntoLValue(Init, lv, /*isInit*/ true);
    return;
  case TEK_Aggregate:
    CGF.EmitAggExpr(Init, AggValueSlot::forLValue(lv,AggValueSlot::IsDestructed,
                                          AggValueSlot::DoesNotNeedGCBarriers,
                                                  AggValueSlot::IsNotAliased));
    return;
  }
  llvm_unreachable("bad evaluation kind");
}

static void EmitDeclInit(CodeGenFunction &CGF, const VarDecl &D,
                         llvm::Constant *DeclPtr) {
  assert(D.hasGlobalStorage() && "VarDecl must have global storage!");
  assert(!D.getType()->isReferenceType() && 
         "Should not call EmitDeclInit on a reference!");
  
  ASTContext &Context = CGF.getContext();

  CharUnits alignment = Context.getDeclAlign(&D);
  QualType type = D.getType();
  LValue lv = CGF.MakeAddrLValue(DeclPtr, type, alignment);

  const Expr *Init = D.getInit();
  if (!CGF.hasAggregateLLVMType(type)) {
    CodeGenModule &CGM = CGF.CGM;
    if (lv.isObjCStrong())
      CGM.getObjCRuntime().EmitObjCGlobalAssign(CGF, CGF.EmitScalarExpr(Init),
                                                DeclPtr, D.isThreadSpecified());
    else if (lv.isObjCWeak())
      CGM.getObjCRuntime().EmitObjCWeakAssign(CGF, CGF.EmitScalarExpr(Init),
                                              DeclPtr);
    else
      CGF.EmitScalarInit(Init, &D, lv, false);
  } else if (type->isAnyComplexType()) {
    CGF.EmitComplexExprIntoAddr(Init, DeclPtr, lv.isVolatile());
  } else {
    CGF.EmitAggExpr(Init, AggValueSlot::forLValue(lv,AggValueSlot::IsDestructed,
                                          AggValueSlot::DoesNotNeedGCBarriers,
                                                  AggValueSlot::IsNotAliased));
  }
}

// CopyObject - Utility to copy an object.  Calls copy constructor as necessary.
// DestPtr is casted to the right type.
static void CopyObject(CodeGenFunction &CGF, const Expr *E, 
                       llvm::Value *DestPtr, llvm::Value *ExceptionPtrPtr) {
  QualType ObjectType = E->getType();

  // Store the throw exception in the exception object.
  if (!CGF.hasAggregateLLVMType(ObjectType)) {
    llvm::Value *Value = CGF.EmitScalarExpr(E);
    const llvm::Type *ValuePtrTy = Value->getType()->getPointerTo();

    CGF.Builder.CreateStore(Value, 
                            CGF.Builder.CreateBitCast(DestPtr, ValuePtrTy));
  } else {
    const llvm::Type *Ty = CGF.ConvertType(ObjectType)->getPointerTo();
    const CXXRecordDecl *RD =
      cast<CXXRecordDecl>(ObjectType->getAs<RecordType>()->getDecl());
    
    llvm::Value *This = CGF.Builder.CreateBitCast(DestPtr, Ty);
    if (RD->hasTrivialCopyConstructor()) {
      CGF.EmitAggExpr(E, This, false);
    } else if (CXXConstructorDecl *CopyCtor
               = RD->getCopyConstructor(CGF.getContext(), 0)) {
      llvm::BasicBlock *PrevLandingPad = CGF.getInvokeDest();
      if (CGF.Exceptions) {
        CodeGenFunction::EHCleanupBlock Cleanup(CGF);
        llvm::Constant *FreeExceptionFn = getFreeExceptionFn(CGF);
        
        // Load the exception pointer.
        llvm::Value *ExceptionPtr = CGF.Builder.CreateLoad(ExceptionPtrPtr);
        CGF.Builder.CreateCall(FreeExceptionFn, ExceptionPtr);
      }

      llvm::Value *Src = CGF.EmitLValue(E).getAddress();
      CGF.setInvokeDest(PrevLandingPad);

      llvm::BasicBlock *TerminateHandler = CGF.getTerminateHandler();
      PrevLandingPad = CGF.getInvokeDest();
      CGF.setInvokeDest(TerminateHandler);

      // Stolen from EmitClassAggrMemberwiseCopy
      llvm::Value *Callee = CGF.CGM.GetAddrOfCXXConstructor(CopyCtor,
                                                            Ctor_Complete);
      CallArgList CallArgs;
      CallArgs.push_back(std::make_pair(RValue::get(This),
                                      CopyCtor->getThisType(CGF.getContext())));

      // Push the Src ptr.
      CallArgs.push_back(std::make_pair(RValue::get(Src),
                                        CopyCtor->getParamDecl(0)->getType()));
      QualType ResultType =
        CopyCtor->getType()->getAs<FunctionType>()->getResultType();
      CGF.EmitCall(CGF.CGM.getTypes().getFunctionInfo(ResultType, CallArgs),
                   Callee, CallArgs, CopyCtor);
      CGF.setInvokeDest(PrevLandingPad);
    } else
      llvm_unreachable("uncopyable object");
  }
}

static void EmitDeclInit(CodeGenFunction &CGF, const VarDecl &D,
                         llvm::Constant *DeclPtr) {
  assert(D.hasGlobalStorage() && "VarDecl must have global storage!");
  assert(!D.getType()->isReferenceType() && 
         "Should not call EmitDeclInit on a reference!");
  
  CodeGenModule &CGM = CGF.CGM;
  ASTContext &Context = CGF.getContext();
    
  const Expr *Init = D.getInit();
  QualType T = D.getType();
  bool isVolatile = Context.getCanonicalType(T).isVolatileQualified();

  if (!CGF.hasAggregateLLVMType(T)) {
    llvm::Value *V = CGF.EmitScalarExpr(Init);
    CGF.EmitStoreOfScalar(V, DeclPtr, isVolatile, T);
  } else if (T->isAnyComplexType()) {
    CGF.EmitComplexExprIntoAddr(Init, DeclPtr, isVolatile);
  } else {
    CGF.EmitAggExpr(Init, DeclPtr, isVolatile);
    
    // Avoid generating destructor(s) for initialized objects. 
    if (!isa<CXXConstructExpr>(Init))
      return;
    
    const ConstantArrayType *Array = Context.getAsConstantArrayType(T);
    if (Array)
      T = Context.getBaseElementType(Array);
    
    const RecordType *RT = T->getAs<RecordType>();
    if (!RT)
      return;
    
    CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
    if (RD->hasTrivialDestructor())
      return;
    
    CXXDestructorDecl *Dtor = RD->getDestructor(Context);
    
    llvm::Constant *DtorFn;
    if (Array) {
      DtorFn = 
        CodeGenFunction(CGM).GenerateCXXAggrDestructorHelper(Dtor, 
                                                             Array, 
                                                             DeclPtr);
      const llvm::Type *Int8PtrTy =
        llvm::Type::getInt8PtrTy(CGM.getLLVMContext());
      DeclPtr = llvm::Constant::getNullValue(Int8PtrTy);
     } else
      DtorFn = CGM.GetAddrOfCXXDestructor(Dtor, Dtor_Complete);

    CGF.EmitCXXGlobalDtorRegistration(DtorFn, DeclPtr);
  }
}

static void EmitDeclInit(CodeGenFunction &CGF, const VarDecl &D,
                         ConstantAddress DeclPtr) {
  assert(D.hasGlobalStorage() && "VarDecl must have global storage!");
  assert(!D.getType()->isReferenceType() && 
         "Should not call EmitDeclInit on a reference!");
  
  QualType type = D.getType();

  // Deduce UPC strict or relaxed from context, if needed
  if (CGF.getContext().getLangOpts().UPC) {
      Qualifiers Quals = type.getQualifiers();
      if (Quals.hasShared() && !Quals.hasStrict() && !Quals.hasRelaxed()) {
        if (D.isUPCInitStrict())
          Quals.addStrict();
        else
          Quals.addRelaxed();

        type = CGF.getContext().getQualifiedType(type.getUnqualifiedType(), Quals);
      }
  }

  LValue lv;
  if(type.getQualifiers().hasShared())
    lv = CGF.EmitSharedVarDeclLValue(DeclPtr, type);
  else
    lv = CGF.MakeAddrLValue(DeclPtr, type);

  const Expr *Init = D.getInit();
  switch (CGF.getEvaluationKind(type)) {
  case TEK_Scalar: {
    CodeGenModule &CGM = CGF.CGM;
    if (lv.isObjCStrong())
      CGM.getObjCRuntime().EmitObjCGlobalAssign(CGF, CGF.EmitScalarExpr(Init),
                                                DeclPtr, D.getTLSKind());
    else if (lv.isObjCWeak())
      CGM.getObjCRuntime().EmitObjCWeakAssign(CGF, CGF.EmitScalarExpr(Init),
                                              DeclPtr);
    else
      CGF.EmitScalarInit(Init, &D, lv, false);
    return;
  }
  case TEK_Complex:
    CGF.EmitComplexExprIntoLValue(Init, lv, /*isInit*/ true);
    return;
  case TEK_Aggregate:
    CGF.EmitAggExpr(Init, AggValueSlot::forLValue(lv,AggValueSlot::IsDestructed,
                                          AggValueSlot::DoesNotNeedGCBarriers,
                                                  AggValueSlot::IsNotAliased));
    return;
  }
  llvm_unreachable("bad evaluation kind");
}

static void EmitDeclInit(CodeGenFunction &CGF, const VarDecl &D,
                         llvm::Constant *DeclPtr) {
  assert(D.hasGlobalStorage() && "VarDecl must have global storage!");
  assert(!D.getType()->isReferenceType() && 
         "Should not call EmitDeclInit on a reference!");
  
  ASTContext &Context = CGF.getContext();
    
  const Expr *Init = D.getInit();
  QualType T = D.getType();
  bool isVolatile = Context.getCanonicalType(T).isVolatileQualified();

  if (!CGF.hasAggregateLLVMType(T)) {
    llvm::Value *V = CGF.EmitScalarExpr(Init);
    CGF.EmitStoreOfScalar(V, DeclPtr, isVolatile, T);
  } else if (T->isAnyComplexType()) {
    CGF.EmitComplexExprIntoAddr(Init, DeclPtr, isVolatile);
  } else {
    CGF.EmitAggExpr(Init, DeclPtr, isVolatile);
  }
}

static void EmitNewInitializer(CodeGenFunction &CGF, const CXXNewExpr *E,
                               llvm::Value *NewPtr,
                               llvm::Value *NumElements) {
  QualType AllocType = E->getAllocatedType();

  if (!E->isArray()) {
    if (CXXConstructorDecl *Ctor = E->getConstructor()) {
      CGF.EmitCXXConstructorCall(Ctor, Ctor_Complete, NewPtr,
                                 E->constructor_arg_begin(),
                                 E->constructor_arg_end());

      return;
    }
    
    // We have a POD type.
    if (E->getNumConstructorArgs() == 0)
      return;

    assert(E->getNumConstructorArgs() == 1 &&
           "Can only have one argument to initializer of POD type.");
      
    const Expr *Init = E->getConstructorArg(0);
    
    if (!CGF.hasAggregateLLVMType(AllocType))
      CGF.Builder.CreateStore(CGF.EmitScalarExpr(Init), NewPtr);
    else if (AllocType->isAnyComplexType())
      CGF.EmitComplexExprIntoAddr(Init, NewPtr, 
                                  AllocType.isVolatileQualified());
    else
      CGF.EmitAggExpr(Init, NewPtr, AllocType.isVolatileQualified());
    return;
  }
  
  if (CXXConstructorDecl *Ctor = E->getConstructor())
    CGF.EmitCXXAggrConstructorCall(Ctor, NumElements, NewPtr);
}