forked from OSchip/llvm-project
1723 lines
62 KiB
C++
1723 lines
62 KiB
C++
//===--- CGClass.cpp - Emit LLVM Code for C++ classes ---------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This contains code dealing with C++ code generation of classes
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//
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//===----------------------------------------------------------------------===//
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#include "CGDebugInfo.h"
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#include "CodeGenFunction.h"
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#include "clang/AST/CXXInheritance.h"
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#include "clang/AST/EvaluatedExprVisitor.h"
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#include "clang/AST/RecordLayout.h"
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#include "clang/AST/StmtCXX.h"
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#include "clang/Frontend/CodeGenOptions.h"
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using namespace clang;
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using namespace CodeGen;
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static CharUnits
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ComputeNonVirtualBaseClassOffset(ASTContext &Context,
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const CXXRecordDecl *DerivedClass,
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CastExpr::path_const_iterator Start,
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CastExpr::path_const_iterator End) {
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CharUnits Offset = CharUnits::Zero();
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const CXXRecordDecl *RD = DerivedClass;
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for (CastExpr::path_const_iterator I = Start; I != End; ++I) {
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const CXXBaseSpecifier *Base = *I;
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assert(!Base->isVirtual() && "Should not see virtual bases here!");
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// Get the layout.
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const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
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const CXXRecordDecl *BaseDecl =
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cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
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// Add the offset.
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Offset += Layout.getBaseClassOffset(BaseDecl);
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RD = BaseDecl;
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}
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return Offset;
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}
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llvm::Constant *
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CodeGenModule::GetNonVirtualBaseClassOffset(const CXXRecordDecl *ClassDecl,
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CastExpr::path_const_iterator PathBegin,
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CastExpr::path_const_iterator PathEnd) {
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assert(PathBegin != PathEnd && "Base path should not be empty!");
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CharUnits Offset =
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ComputeNonVirtualBaseClassOffset(getContext(), ClassDecl,
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PathBegin, PathEnd);
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if (Offset.isZero())
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return 0;
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llvm::Type *PtrDiffTy =
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Types.ConvertType(getContext().getPointerDiffType());
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return llvm::ConstantInt::get(PtrDiffTy, Offset.getQuantity());
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}
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/// Gets the address of a direct base class within a complete object.
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/// This should only be used for (1) non-virtual bases or (2) virtual bases
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/// when the type is known to be complete (e.g. in complete destructors).
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///
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/// The object pointed to by 'This' is assumed to be non-null.
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llvm::Value *
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CodeGenFunction::GetAddressOfDirectBaseInCompleteClass(llvm::Value *This,
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const CXXRecordDecl *Derived,
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const CXXRecordDecl *Base,
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bool BaseIsVirtual) {
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// 'this' must be a pointer (in some address space) to Derived.
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assert(This->getType()->isPointerTy() &&
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cast<llvm::PointerType>(This->getType())->getElementType()
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== ConvertType(Derived));
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// Compute the offset of the virtual base.
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CharUnits Offset;
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const ASTRecordLayout &Layout = getContext().getASTRecordLayout(Derived);
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if (BaseIsVirtual)
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Offset = Layout.getVBaseClassOffset(Base);
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else
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Offset = Layout.getBaseClassOffset(Base);
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// Shift and cast down to the base type.
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// TODO: for complete types, this should be possible with a GEP.
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llvm::Value *V = This;
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if (Offset.isPositive()) {
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V = Builder.CreateBitCast(V, Int8PtrTy);
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V = Builder.CreateConstInBoundsGEP1_64(V, Offset.getQuantity());
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}
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V = Builder.CreateBitCast(V, ConvertType(Base)->getPointerTo());
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return V;
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}
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static llvm::Value *
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ApplyNonVirtualAndVirtualOffset(CodeGenFunction &CGF, llvm::Value *ThisPtr,
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CharUnits NonVirtual, llvm::Value *Virtual) {
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llvm::Type *PtrDiffTy =
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CGF.ConvertType(CGF.getContext().getPointerDiffType());
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llvm::Value *NonVirtualOffset = 0;
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if (!NonVirtual.isZero())
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NonVirtualOffset = llvm::ConstantInt::get(PtrDiffTy,
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NonVirtual.getQuantity());
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llvm::Value *BaseOffset;
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if (Virtual) {
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if (NonVirtualOffset)
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BaseOffset = CGF.Builder.CreateAdd(Virtual, NonVirtualOffset);
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else
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BaseOffset = Virtual;
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} else
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BaseOffset = NonVirtualOffset;
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// Apply the base offset.
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ThisPtr = CGF.Builder.CreateBitCast(ThisPtr, CGF.Int8PtrTy);
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ThisPtr = CGF.Builder.CreateGEP(ThisPtr, BaseOffset, "add.ptr");
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return ThisPtr;
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}
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llvm::Value *
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CodeGenFunction::GetAddressOfBaseClass(llvm::Value *Value,
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const CXXRecordDecl *Derived,
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CastExpr::path_const_iterator PathBegin,
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CastExpr::path_const_iterator PathEnd,
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bool NullCheckValue) {
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assert(PathBegin != PathEnd && "Base path should not be empty!");
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CastExpr::path_const_iterator Start = PathBegin;
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const CXXRecordDecl *VBase = 0;
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// Get the virtual base.
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if ((*Start)->isVirtual()) {
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VBase =
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cast<CXXRecordDecl>((*Start)->getType()->getAs<RecordType>()->getDecl());
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++Start;
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}
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CharUnits NonVirtualOffset =
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ComputeNonVirtualBaseClassOffset(getContext(), VBase ? VBase : Derived,
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Start, PathEnd);
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// Get the base pointer type.
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llvm::Type *BasePtrTy =
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ConvertType((PathEnd[-1])->getType())->getPointerTo();
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if (NonVirtualOffset.isZero() && !VBase) {
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// Just cast back.
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return Builder.CreateBitCast(Value, BasePtrTy);
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}
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llvm::BasicBlock *CastNull = 0;
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llvm::BasicBlock *CastNotNull = 0;
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llvm::BasicBlock *CastEnd = 0;
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if (NullCheckValue) {
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CastNull = createBasicBlock("cast.null");
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CastNotNull = createBasicBlock("cast.notnull");
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CastEnd = createBasicBlock("cast.end");
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llvm::Value *IsNull = Builder.CreateIsNull(Value);
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Builder.CreateCondBr(IsNull, CastNull, CastNotNull);
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EmitBlock(CastNotNull);
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}
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llvm::Value *VirtualOffset = 0;
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if (VBase) {
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if (Derived->hasAttr<FinalAttr>()) {
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VirtualOffset = 0;
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const ASTRecordLayout &Layout = getContext().getASTRecordLayout(Derived);
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CharUnits VBaseOffset = Layout.getVBaseClassOffset(VBase);
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NonVirtualOffset += VBaseOffset;
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} else
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VirtualOffset = GetVirtualBaseClassOffset(Value, Derived, VBase);
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}
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// Apply the offsets.
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Value = ApplyNonVirtualAndVirtualOffset(*this, Value,
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NonVirtualOffset,
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VirtualOffset);
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// Cast back.
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Value = Builder.CreateBitCast(Value, BasePtrTy);
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if (NullCheckValue) {
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Builder.CreateBr(CastEnd);
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EmitBlock(CastNull);
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Builder.CreateBr(CastEnd);
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EmitBlock(CastEnd);
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llvm::PHINode *PHI = Builder.CreatePHI(Value->getType(), 2);
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PHI->addIncoming(Value, CastNotNull);
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PHI->addIncoming(llvm::Constant::getNullValue(Value->getType()),
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CastNull);
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Value = PHI;
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}
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return Value;
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}
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llvm::Value *
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CodeGenFunction::GetAddressOfDerivedClass(llvm::Value *Value,
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const CXXRecordDecl *Derived,
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CastExpr::path_const_iterator PathBegin,
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CastExpr::path_const_iterator PathEnd,
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bool NullCheckValue) {
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assert(PathBegin != PathEnd && "Base path should not be empty!");
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QualType DerivedTy =
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getContext().getCanonicalType(getContext().getTagDeclType(Derived));
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llvm::Type *DerivedPtrTy = ConvertType(DerivedTy)->getPointerTo();
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llvm::Value *NonVirtualOffset =
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CGM.GetNonVirtualBaseClassOffset(Derived, PathBegin, PathEnd);
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if (!NonVirtualOffset) {
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// No offset, we can just cast back.
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return Builder.CreateBitCast(Value, DerivedPtrTy);
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}
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llvm::BasicBlock *CastNull = 0;
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llvm::BasicBlock *CastNotNull = 0;
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llvm::BasicBlock *CastEnd = 0;
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if (NullCheckValue) {
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CastNull = createBasicBlock("cast.null");
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CastNotNull = createBasicBlock("cast.notnull");
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CastEnd = createBasicBlock("cast.end");
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llvm::Value *IsNull = Builder.CreateIsNull(Value);
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Builder.CreateCondBr(IsNull, CastNull, CastNotNull);
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EmitBlock(CastNotNull);
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}
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// Apply the offset.
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Value = Builder.CreatePtrToInt(Value, NonVirtualOffset->getType());
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Value = Builder.CreateSub(Value, NonVirtualOffset);
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Value = Builder.CreateIntToPtr(Value, DerivedPtrTy);
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// Just cast.
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Value = Builder.CreateBitCast(Value, DerivedPtrTy);
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if (NullCheckValue) {
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Builder.CreateBr(CastEnd);
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EmitBlock(CastNull);
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Builder.CreateBr(CastEnd);
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EmitBlock(CastEnd);
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llvm::PHINode *PHI = Builder.CreatePHI(Value->getType(), 2);
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PHI->addIncoming(Value, CastNotNull);
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PHI->addIncoming(llvm::Constant::getNullValue(Value->getType()),
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CastNull);
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Value = PHI;
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}
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return Value;
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}
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/// GetVTTParameter - Return the VTT parameter that should be passed to a
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/// base constructor/destructor with virtual bases.
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static llvm::Value *GetVTTParameter(CodeGenFunction &CGF, GlobalDecl GD,
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bool ForVirtualBase) {
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if (!CodeGenVTables::needsVTTParameter(GD)) {
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// This constructor/destructor does not need a VTT parameter.
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return 0;
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}
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const CXXRecordDecl *RD = cast<CXXMethodDecl>(CGF.CurFuncDecl)->getParent();
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const CXXRecordDecl *Base = cast<CXXMethodDecl>(GD.getDecl())->getParent();
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llvm::Value *VTT;
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uint64_t SubVTTIndex;
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// If the record matches the base, this is the complete ctor/dtor
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// variant calling the base variant in a class with virtual bases.
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if (RD == Base) {
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assert(!CodeGenVTables::needsVTTParameter(CGF.CurGD) &&
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"doing no-op VTT offset in base dtor/ctor?");
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assert(!ForVirtualBase && "Can't have same class as virtual base!");
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SubVTTIndex = 0;
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} else {
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const ASTRecordLayout &Layout =
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CGF.getContext().getASTRecordLayout(RD);
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CharUnits BaseOffset = ForVirtualBase ?
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Layout.getVBaseClassOffset(Base) :
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Layout.getBaseClassOffset(Base);
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SubVTTIndex =
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CGF.CGM.getVTables().getSubVTTIndex(RD, BaseSubobject(Base, BaseOffset));
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assert(SubVTTIndex != 0 && "Sub-VTT index must be greater than zero!");
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}
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if (CodeGenVTables::needsVTTParameter(CGF.CurGD)) {
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// A VTT parameter was passed to the constructor, use it.
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VTT = CGF.LoadCXXVTT();
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VTT = CGF.Builder.CreateConstInBoundsGEP1_64(VTT, SubVTTIndex);
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} else {
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// We're the complete constructor, so get the VTT by name.
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VTT = CGF.CGM.getVTables().GetAddrOfVTT(RD);
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VTT = CGF.Builder.CreateConstInBoundsGEP2_64(VTT, 0, SubVTTIndex);
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}
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return VTT;
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}
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namespace {
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/// Call the destructor for a direct base class.
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struct CallBaseDtor : EHScopeStack::Cleanup {
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const CXXRecordDecl *BaseClass;
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bool BaseIsVirtual;
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CallBaseDtor(const CXXRecordDecl *Base, bool BaseIsVirtual)
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: BaseClass(Base), BaseIsVirtual(BaseIsVirtual) {}
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void Emit(CodeGenFunction &CGF, Flags flags) {
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const CXXRecordDecl *DerivedClass =
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cast<CXXMethodDecl>(CGF.CurCodeDecl)->getParent();
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const CXXDestructorDecl *D = BaseClass->getDestructor();
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llvm::Value *Addr =
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CGF.GetAddressOfDirectBaseInCompleteClass(CGF.LoadCXXThis(),
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DerivedClass, BaseClass,
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BaseIsVirtual);
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CGF.EmitCXXDestructorCall(D, Dtor_Base, BaseIsVirtual, Addr);
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}
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};
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/// A visitor which checks whether an initializer uses 'this' in a
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/// way which requires the vtable to be properly set.
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struct DynamicThisUseChecker : EvaluatedExprVisitor<DynamicThisUseChecker> {
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typedef EvaluatedExprVisitor<DynamicThisUseChecker> super;
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bool UsesThis;
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DynamicThisUseChecker(ASTContext &C) : super(C), UsesThis(false) {}
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// Black-list all explicit and implicit references to 'this'.
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//
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// Do we need to worry about external references to 'this' derived
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// from arbitrary code? If so, then anything which runs arbitrary
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// external code might potentially access the vtable.
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void VisitCXXThisExpr(CXXThisExpr *E) { UsesThis = true; }
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};
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}
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static bool BaseInitializerUsesThis(ASTContext &C, const Expr *Init) {
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DynamicThisUseChecker Checker(C);
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Checker.Visit(const_cast<Expr*>(Init));
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return Checker.UsesThis;
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}
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static void EmitBaseInitializer(CodeGenFunction &CGF,
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const CXXRecordDecl *ClassDecl,
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CXXCtorInitializer *BaseInit,
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CXXCtorType CtorType) {
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assert(BaseInit->isBaseInitializer() &&
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"Must have base initializer!");
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llvm::Value *ThisPtr = CGF.LoadCXXThis();
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const Type *BaseType = BaseInit->getBaseClass();
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CXXRecordDecl *BaseClassDecl =
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cast<CXXRecordDecl>(BaseType->getAs<RecordType>()->getDecl());
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bool isBaseVirtual = BaseInit->isBaseVirtual();
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// The base constructor doesn't construct virtual bases.
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if (CtorType == Ctor_Base && isBaseVirtual)
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return;
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// If the initializer for the base (other than the constructor
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// itself) accesses 'this' in any way, we need to initialize the
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// vtables.
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if (BaseInitializerUsesThis(CGF.getContext(), BaseInit->getInit()))
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CGF.InitializeVTablePointers(ClassDecl);
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// We can pretend to be a complete class because it only matters for
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// virtual bases, and we only do virtual bases for complete ctors.
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llvm::Value *V =
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CGF.GetAddressOfDirectBaseInCompleteClass(ThisPtr, ClassDecl,
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BaseClassDecl,
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isBaseVirtual);
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CharUnits Alignment = CGF.getContext().getTypeAlignInChars(BaseType);
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AggValueSlot AggSlot =
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AggValueSlot::forAddr(V, Alignment, Qualifiers(),
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AggValueSlot::IsDestructed,
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AggValueSlot::DoesNotNeedGCBarriers,
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AggValueSlot::IsNotAliased);
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CGF.EmitAggExpr(BaseInit->getInit(), AggSlot);
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if (CGF.CGM.getLangOptions().Exceptions &&
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!BaseClassDecl->hasTrivialDestructor())
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CGF.EHStack.pushCleanup<CallBaseDtor>(EHCleanup, BaseClassDecl,
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isBaseVirtual);
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}
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static void EmitAggMemberInitializer(CodeGenFunction &CGF,
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LValue LHS,
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Expr *Init,
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llvm::Value *ArrayIndexVar,
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QualType T,
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ArrayRef<VarDecl *> ArrayIndexes,
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unsigned Index) {
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if (Index == ArrayIndexes.size()) {
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CodeGenFunction::RunCleanupsScope Cleanups(CGF);
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LValue LV = LHS;
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if (ArrayIndexVar) {
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// If we have an array index variable, load it and use it as an offset.
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// Then, increment the value.
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llvm::Value *Dest = LHS.getAddress();
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llvm::Value *ArrayIndex = CGF.Builder.CreateLoad(ArrayIndexVar);
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Dest = CGF.Builder.CreateInBoundsGEP(Dest, ArrayIndex, "destaddress");
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llvm::Value *Next = llvm::ConstantInt::get(ArrayIndex->getType(), 1);
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Next = CGF.Builder.CreateAdd(ArrayIndex, Next, "inc");
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CGF.Builder.CreateStore(Next, ArrayIndexVar);
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// Update the LValue.
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LV.setAddress(Dest);
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CharUnits Align = CGF.getContext().getTypeAlignInChars(T);
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LV.setAlignment(std::min(Align, LV.getAlignment()));
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}
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if (!CGF.hasAggregateLLVMType(T)) {
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CGF.EmitScalarInit(Init, /*decl*/ 0, LV, false);
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} else if (T->isAnyComplexType()) {
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CGF.EmitComplexExprIntoAddr(Init, LV.getAddress(),
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LV.isVolatileQualified());
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} else {
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AggValueSlot Slot =
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AggValueSlot::forLValue(LV,
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AggValueSlot::IsDestructed,
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AggValueSlot::DoesNotNeedGCBarriers,
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AggValueSlot::IsNotAliased);
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CGF.EmitAggExpr(Init, Slot);
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}
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return;
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}
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const ConstantArrayType *Array = CGF.getContext().getAsConstantArrayType(T);
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assert(Array && "Array initialization without the array type?");
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llvm::Value *IndexVar
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= CGF.GetAddrOfLocalVar(ArrayIndexes[Index]);
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assert(IndexVar && "Array index variable not loaded");
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// Initialize this index variable to zero.
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llvm::Value* Zero
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= llvm::Constant::getNullValue(
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CGF.ConvertType(CGF.getContext().getSizeType()));
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CGF.Builder.CreateStore(Zero, IndexVar);
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// Start the loop with a block that tests the condition.
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llvm::BasicBlock *CondBlock = CGF.createBasicBlock("for.cond");
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llvm::BasicBlock *AfterFor = CGF.createBasicBlock("for.end");
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CGF.EmitBlock(CondBlock);
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llvm::BasicBlock *ForBody = CGF.createBasicBlock("for.body");
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// Generate: if (loop-index < number-of-elements) fall to the loop body,
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// otherwise, go to the block after the for-loop.
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uint64_t NumElements = Array->getSize().getZExtValue();
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llvm::Value *Counter = CGF.Builder.CreateLoad(IndexVar);
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llvm::Value *NumElementsPtr =
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llvm::ConstantInt::get(Counter->getType(), NumElements);
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llvm::Value *IsLess = CGF.Builder.CreateICmpULT(Counter, NumElementsPtr,
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"isless");
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// If the condition is true, execute the body.
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CGF.Builder.CreateCondBr(IsLess, ForBody, AfterFor);
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CGF.EmitBlock(ForBody);
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llvm::BasicBlock *ContinueBlock = CGF.createBasicBlock("for.inc");
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{
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CodeGenFunction::RunCleanupsScope Cleanups(CGF);
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// Inside the loop body recurse to emit the inner loop or, eventually, the
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// constructor call.
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EmitAggMemberInitializer(CGF, LHS, Init, ArrayIndexVar,
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Array->getElementType(), ArrayIndexes, Index + 1);
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}
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CGF.EmitBlock(ContinueBlock);
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// Emit the increment of the loop counter.
|
|
llvm::Value *NextVal = llvm::ConstantInt::get(Counter->getType(), 1);
|
|
Counter = CGF.Builder.CreateLoad(IndexVar);
|
|
NextVal = CGF.Builder.CreateAdd(Counter, NextVal, "inc");
|
|
CGF.Builder.CreateStore(NextVal, IndexVar);
|
|
|
|
// Finally, branch back up to the condition for the next iteration.
|
|
CGF.EmitBranch(CondBlock);
|
|
|
|
// Emit the fall-through block.
|
|
CGF.EmitBlock(AfterFor, true);
|
|
}
|
|
|
|
namespace {
|
|
struct CallMemberDtor : EHScopeStack::Cleanup {
|
|
llvm::Value *V;
|
|
CXXDestructorDecl *Dtor;
|
|
|
|
CallMemberDtor(llvm::Value *V, CXXDestructorDecl *Dtor)
|
|
: V(V), Dtor(Dtor) {}
|
|
|
|
void Emit(CodeGenFunction &CGF, Flags flags) {
|
|
CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete, /*ForVirtualBase=*/false,
|
|
V);
|
|
}
|
|
};
|
|
}
|
|
|
|
static bool hasTrivialCopyOrMoveConstructor(const CXXRecordDecl *Record,
|
|
bool Moving) {
|
|
return Moving ? Record->hasTrivialMoveConstructor() :
|
|
Record->hasTrivialCopyConstructor();
|
|
}
|
|
|
|
static void EmitMemberInitializer(CodeGenFunction &CGF,
|
|
const CXXRecordDecl *ClassDecl,
|
|
CXXCtorInitializer *MemberInit,
|
|
const CXXConstructorDecl *Constructor,
|
|
FunctionArgList &Args) {
|
|
assert(MemberInit->isAnyMemberInitializer() &&
|
|
"Must have member initializer!");
|
|
assert(MemberInit->getInit() && "Must have initializer!");
|
|
|
|
// non-static data member initializers.
|
|
FieldDecl *Field = MemberInit->getAnyMember();
|
|
QualType FieldType = Field->getType();
|
|
|
|
llvm::Value *ThisPtr = CGF.LoadCXXThis();
|
|
LValue LHS;
|
|
|
|
// If we are initializing an anonymous union field, drill down to the field.
|
|
if (MemberInit->isIndirectMemberInitializer()) {
|
|
LHS = CGF.EmitLValueForAnonRecordField(ThisPtr,
|
|
MemberInit->getIndirectMember(), 0);
|
|
FieldType = MemberInit->getIndirectMember()->getAnonField()->getType();
|
|
} else {
|
|
LHS = CGF.EmitLValueForFieldInitialization(ThisPtr, Field, 0);
|
|
}
|
|
|
|
// Special case: if we are in a copy or move constructor, and we are copying
|
|
// an array of PODs or classes with trivial copy constructors, ignore the
|
|
// AST and perform the copy we know is equivalent.
|
|
// FIXME: This is hacky at best... if we had a bit more explicit information
|
|
// in the AST, we could generalize it more easily.
|
|
const ConstantArrayType *Array
|
|
= CGF.getContext().getAsConstantArrayType(FieldType);
|
|
if (Array && Constructor->isImplicitlyDefined() &&
|
|
Constructor->isCopyOrMoveConstructor()) {
|
|
QualType BaseElementTy = CGF.getContext().getBaseElementType(Array);
|
|
const CXXRecordDecl *Record = BaseElementTy->getAsCXXRecordDecl();
|
|
if (BaseElementTy.isPODType(CGF.getContext()) ||
|
|
(Record && hasTrivialCopyOrMoveConstructor(Record,
|
|
Constructor->isMoveConstructor()))) {
|
|
// Find the source pointer. We knows it's the last argument because
|
|
// we know we're in a copy constructor.
|
|
unsigned SrcArgIndex = Args.size() - 1;
|
|
llvm::Value *SrcPtr
|
|
= CGF.Builder.CreateLoad(CGF.GetAddrOfLocalVar(Args[SrcArgIndex]));
|
|
LValue Src = CGF.EmitLValueForFieldInitialization(SrcPtr, Field, 0);
|
|
|
|
// Copy the aggregate.
|
|
CGF.EmitAggregateCopy(LHS.getAddress(), Src.getAddress(), FieldType,
|
|
LHS.isVolatileQualified());
|
|
return;
|
|
}
|
|
}
|
|
|
|
ArrayRef<VarDecl *> ArrayIndexes;
|
|
if (MemberInit->getNumArrayIndices())
|
|
ArrayIndexes = MemberInit->getArrayIndexes();
|
|
CGF.EmitInitializerForField(Field, LHS, MemberInit->getInit(), ArrayIndexes);
|
|
}
|
|
|
|
void CodeGenFunction::EmitInitializerForField(FieldDecl *Field,
|
|
LValue LHS, Expr *Init,
|
|
ArrayRef<VarDecl *> ArrayIndexes) {
|
|
QualType FieldType = Field->getType();
|
|
if (!hasAggregateLLVMType(FieldType)) {
|
|
if (LHS.isSimple()) {
|
|
EmitExprAsInit(Init, Field, LHS, false);
|
|
} else {
|
|
RValue RHS = RValue::get(EmitScalarExpr(Init));
|
|
EmitStoreThroughLValue(RHS, LHS);
|
|
}
|
|
} else if (FieldType->isAnyComplexType()) {
|
|
EmitComplexExprIntoAddr(Init, LHS.getAddress(), LHS.isVolatileQualified());
|
|
} else {
|
|
llvm::Value *ArrayIndexVar = 0;
|
|
if (ArrayIndexes.size()) {
|
|
llvm::Type *SizeTy = ConvertType(getContext().getSizeType());
|
|
|
|
// The LHS is a pointer to the first object we'll be constructing, as
|
|
// a flat array.
|
|
QualType BaseElementTy = getContext().getBaseElementType(FieldType);
|
|
llvm::Type *BasePtr = ConvertType(BaseElementTy);
|
|
BasePtr = llvm::PointerType::getUnqual(BasePtr);
|
|
llvm::Value *BaseAddrPtr = Builder.CreateBitCast(LHS.getAddress(),
|
|
BasePtr);
|
|
LHS = MakeAddrLValue(BaseAddrPtr, BaseElementTy);
|
|
|
|
// Create an array index that will be used to walk over all of the
|
|
// objects we're constructing.
|
|
ArrayIndexVar = CreateTempAlloca(SizeTy, "object.index");
|
|
llvm::Value *Zero = llvm::Constant::getNullValue(SizeTy);
|
|
Builder.CreateStore(Zero, ArrayIndexVar);
|
|
|
|
|
|
// Emit the block variables for the array indices, if any.
|
|
for (unsigned I = 0, N = ArrayIndexes.size(); I != N; ++I)
|
|
EmitAutoVarDecl(*ArrayIndexes[I]);
|
|
}
|
|
|
|
EmitAggMemberInitializer(*this, LHS, Init, ArrayIndexVar, FieldType,
|
|
ArrayIndexes, 0);
|
|
|
|
if (!CGM.getLangOptions().Exceptions)
|
|
return;
|
|
|
|
// FIXME: If we have an array of classes w/ non-trivial destructors,
|
|
// we need to destroy in reverse order of construction along the exception
|
|
// path.
|
|
const RecordType *RT = FieldType->getAs<RecordType>();
|
|
if (!RT)
|
|
return;
|
|
|
|
CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
|
|
if (!RD->hasTrivialDestructor())
|
|
EHStack.pushCleanup<CallMemberDtor>(EHCleanup, LHS.getAddress(),
|
|
RD->getDestructor());
|
|
}
|
|
}
|
|
|
|
/// Checks whether the given constructor is a valid subject for the
|
|
/// complete-to-base constructor delegation optimization, i.e.
|
|
/// emitting the complete constructor as a simple call to the base
|
|
/// constructor.
|
|
static bool IsConstructorDelegationValid(const CXXConstructorDecl *Ctor) {
|
|
|
|
// Currently we disable the optimization for classes with virtual
|
|
// bases because (1) the addresses of parameter variables need to be
|
|
// consistent across all initializers but (2) the delegate function
|
|
// call necessarily creates a second copy of the parameter variable.
|
|
//
|
|
// The limiting example (purely theoretical AFAIK):
|
|
// struct A { A(int &c) { c++; } };
|
|
// struct B : virtual A {
|
|
// B(int count) : A(count) { printf("%d\n", count); }
|
|
// };
|
|
// ...although even this example could in principle be emitted as a
|
|
// delegation since the address of the parameter doesn't escape.
|
|
if (Ctor->getParent()->getNumVBases()) {
|
|
// TODO: white-list trivial vbase initializers. This case wouldn't
|
|
// be subject to the restrictions below.
|
|
|
|
// TODO: white-list cases where:
|
|
// - there are no non-reference parameters to the constructor
|
|
// - the initializers don't access any non-reference parameters
|
|
// - the initializers don't take the address of non-reference
|
|
// parameters
|
|
// - etc.
|
|
// If we ever add any of the above cases, remember that:
|
|
// - function-try-blocks will always blacklist this optimization
|
|
// - we need to perform the constructor prologue and cleanup in
|
|
// EmitConstructorBody.
|
|
|
|
return false;
|
|
}
|
|
|
|
// We also disable the optimization for variadic functions because
|
|
// it's impossible to "re-pass" varargs.
|
|
if (Ctor->getType()->getAs<FunctionProtoType>()->isVariadic())
|
|
return false;
|
|
|
|
// FIXME: Decide if we can do a delegation of a delegating constructor.
|
|
if (Ctor->isDelegatingConstructor())
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
/// EmitConstructorBody - Emits the body of the current constructor.
|
|
void CodeGenFunction::EmitConstructorBody(FunctionArgList &Args) {
|
|
const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(CurGD.getDecl());
|
|
CXXCtorType CtorType = CurGD.getCtorType();
|
|
|
|
// Before we go any further, try the complete->base constructor
|
|
// delegation optimization.
|
|
if (CtorType == Ctor_Complete && IsConstructorDelegationValid(Ctor)) {
|
|
if (CGDebugInfo *DI = getDebugInfo())
|
|
DI->EmitLocation(Builder, Ctor->getLocEnd());
|
|
EmitDelegateCXXConstructorCall(Ctor, Ctor_Base, Args);
|
|
return;
|
|
}
|
|
|
|
Stmt *Body = Ctor->getBody();
|
|
|
|
// Enter the function-try-block before the constructor prologue if
|
|
// applicable.
|
|
bool IsTryBody = (Body && isa<CXXTryStmt>(Body));
|
|
if (IsTryBody)
|
|
EnterCXXTryStmt(*cast<CXXTryStmt>(Body), true);
|
|
|
|
EHScopeStack::stable_iterator CleanupDepth = EHStack.stable_begin();
|
|
|
|
// Emit the constructor prologue, i.e. the base and member
|
|
// initializers.
|
|
EmitCtorPrologue(Ctor, CtorType, Args);
|
|
|
|
// Emit the body of the statement.
|
|
if (IsTryBody)
|
|
EmitStmt(cast<CXXTryStmt>(Body)->getTryBlock());
|
|
else if (Body)
|
|
EmitStmt(Body);
|
|
|
|
// Emit any cleanup blocks associated with the member or base
|
|
// initializers, which includes (along the exceptional path) the
|
|
// destructors for those members and bases that were fully
|
|
// constructed.
|
|
PopCleanupBlocks(CleanupDepth);
|
|
|
|
if (IsTryBody)
|
|
ExitCXXTryStmt(*cast<CXXTryStmt>(Body), true);
|
|
}
|
|
|
|
/// EmitCtorPrologue - This routine generates necessary code to initialize
|
|
/// base classes and non-static data members belonging to this constructor.
|
|
void CodeGenFunction::EmitCtorPrologue(const CXXConstructorDecl *CD,
|
|
CXXCtorType CtorType,
|
|
FunctionArgList &Args) {
|
|
if (CD->isDelegatingConstructor())
|
|
return EmitDelegatingCXXConstructorCall(CD, Args);
|
|
|
|
const CXXRecordDecl *ClassDecl = CD->getParent();
|
|
|
|
SmallVector<CXXCtorInitializer *, 8> MemberInitializers;
|
|
|
|
for (CXXConstructorDecl::init_const_iterator B = CD->init_begin(),
|
|
E = CD->init_end();
|
|
B != E; ++B) {
|
|
CXXCtorInitializer *Member = (*B);
|
|
|
|
if (Member->isBaseInitializer()) {
|
|
EmitBaseInitializer(*this, ClassDecl, Member, CtorType);
|
|
} else {
|
|
assert(Member->isAnyMemberInitializer() &&
|
|
"Delegating initializer on non-delegating constructor");
|
|
MemberInitializers.push_back(Member);
|
|
}
|
|
}
|
|
|
|
InitializeVTablePointers(ClassDecl);
|
|
|
|
for (unsigned I = 0, E = MemberInitializers.size(); I != E; ++I)
|
|
EmitMemberInitializer(*this, ClassDecl, MemberInitializers[I], CD, Args);
|
|
}
|
|
|
|
static bool
|
|
FieldHasTrivialDestructorBody(ASTContext &Context, const FieldDecl *Field);
|
|
|
|
static bool
|
|
HasTrivialDestructorBody(ASTContext &Context,
|
|
const CXXRecordDecl *BaseClassDecl,
|
|
const CXXRecordDecl *MostDerivedClassDecl)
|
|
{
|
|
// If the destructor is trivial we don't have to check anything else.
|
|
if (BaseClassDecl->hasTrivialDestructor())
|
|
return true;
|
|
|
|
if (!BaseClassDecl->getDestructor()->hasTrivialBody())
|
|
return false;
|
|
|
|
// Check fields.
|
|
for (CXXRecordDecl::field_iterator I = BaseClassDecl->field_begin(),
|
|
E = BaseClassDecl->field_end(); I != E; ++I) {
|
|
const FieldDecl *Field = *I;
|
|
|
|
if (!FieldHasTrivialDestructorBody(Context, Field))
|
|
return false;
|
|
}
|
|
|
|
// Check non-virtual bases.
|
|
for (CXXRecordDecl::base_class_const_iterator I =
|
|
BaseClassDecl->bases_begin(), E = BaseClassDecl->bases_end();
|
|
I != E; ++I) {
|
|
if (I->isVirtual())
|
|
continue;
|
|
|
|
const CXXRecordDecl *NonVirtualBase =
|
|
cast<CXXRecordDecl>(I->getType()->castAs<RecordType>()->getDecl());
|
|
if (!HasTrivialDestructorBody(Context, NonVirtualBase,
|
|
MostDerivedClassDecl))
|
|
return false;
|
|
}
|
|
|
|
if (BaseClassDecl == MostDerivedClassDecl) {
|
|
// Check virtual bases.
|
|
for (CXXRecordDecl::base_class_const_iterator I =
|
|
BaseClassDecl->vbases_begin(), E = BaseClassDecl->vbases_end();
|
|
I != E; ++I) {
|
|
const CXXRecordDecl *VirtualBase =
|
|
cast<CXXRecordDecl>(I->getType()->castAs<RecordType>()->getDecl());
|
|
if (!HasTrivialDestructorBody(Context, VirtualBase,
|
|
MostDerivedClassDecl))
|
|
return false;
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
static bool
|
|
FieldHasTrivialDestructorBody(ASTContext &Context,
|
|
const FieldDecl *Field)
|
|
{
|
|
QualType FieldBaseElementType = Context.getBaseElementType(Field->getType());
|
|
|
|
const RecordType *RT = FieldBaseElementType->getAs<RecordType>();
|
|
if (!RT)
|
|
return true;
|
|
|
|
CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
|
|
return HasTrivialDestructorBody(Context, FieldClassDecl, FieldClassDecl);
|
|
}
|
|
|
|
/// CanSkipVTablePointerInitialization - Check whether we need to initialize
|
|
/// any vtable pointers before calling this destructor.
|
|
static bool CanSkipVTablePointerInitialization(ASTContext &Context,
|
|
const CXXDestructorDecl *Dtor) {
|
|
if (!Dtor->hasTrivialBody())
|
|
return false;
|
|
|
|
// Check the fields.
|
|
const CXXRecordDecl *ClassDecl = Dtor->getParent();
|
|
for (CXXRecordDecl::field_iterator I = ClassDecl->field_begin(),
|
|
E = ClassDecl->field_end(); I != E; ++I) {
|
|
const FieldDecl *Field = *I;
|
|
|
|
if (!FieldHasTrivialDestructorBody(Context, Field))
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/// EmitDestructorBody - Emits the body of the current destructor.
|
|
void CodeGenFunction::EmitDestructorBody(FunctionArgList &Args) {
|
|
const CXXDestructorDecl *Dtor = cast<CXXDestructorDecl>(CurGD.getDecl());
|
|
CXXDtorType DtorType = CurGD.getDtorType();
|
|
|
|
// The call to operator delete in a deleting destructor happens
|
|
// outside of the function-try-block, which means it's always
|
|
// possible to delegate the destructor body to the complete
|
|
// destructor. Do so.
|
|
if (DtorType == Dtor_Deleting) {
|
|
EnterDtorCleanups(Dtor, Dtor_Deleting);
|
|
EmitCXXDestructorCall(Dtor, Dtor_Complete, /*ForVirtualBase=*/false,
|
|
LoadCXXThis());
|
|
PopCleanupBlock();
|
|
return;
|
|
}
|
|
|
|
Stmt *Body = Dtor->getBody();
|
|
|
|
// If the body is a function-try-block, enter the try before
|
|
// anything else.
|
|
bool isTryBody = (Body && isa<CXXTryStmt>(Body));
|
|
if (isTryBody)
|
|
EnterCXXTryStmt(*cast<CXXTryStmt>(Body), true);
|
|
|
|
// Enter the epilogue cleanups.
|
|
RunCleanupsScope DtorEpilogue(*this);
|
|
|
|
// If this is the complete variant, just invoke the base variant;
|
|
// the epilogue will destruct the virtual bases. But we can't do
|
|
// this optimization if the body is a function-try-block, because
|
|
// we'd introduce *two* handler blocks.
|
|
switch (DtorType) {
|
|
case Dtor_Deleting: llvm_unreachable("already handled deleting case");
|
|
|
|
case Dtor_Complete:
|
|
// Enter the cleanup scopes for virtual bases.
|
|
EnterDtorCleanups(Dtor, Dtor_Complete);
|
|
|
|
if (!isTryBody) {
|
|
EmitCXXDestructorCall(Dtor, Dtor_Base, /*ForVirtualBase=*/false,
|
|
LoadCXXThis());
|
|
break;
|
|
}
|
|
// Fallthrough: act like we're in the base variant.
|
|
|
|
case Dtor_Base:
|
|
// Enter the cleanup scopes for fields and non-virtual bases.
|
|
EnterDtorCleanups(Dtor, Dtor_Base);
|
|
|
|
// Initialize the vtable pointers before entering the body.
|
|
if (!CanSkipVTablePointerInitialization(getContext(), Dtor))
|
|
InitializeVTablePointers(Dtor->getParent());
|
|
|
|
if (isTryBody)
|
|
EmitStmt(cast<CXXTryStmt>(Body)->getTryBlock());
|
|
else if (Body)
|
|
EmitStmt(Body);
|
|
else {
|
|
assert(Dtor->isImplicit() && "bodyless dtor not implicit");
|
|
// nothing to do besides what's in the epilogue
|
|
}
|
|
// -fapple-kext must inline any call to this dtor into
|
|
// the caller's body.
|
|
if (getContext().getLangOptions().AppleKext)
|
|
CurFn->addFnAttr(llvm::Attribute::AlwaysInline);
|
|
break;
|
|
}
|
|
|
|
// Jump out through the epilogue cleanups.
|
|
DtorEpilogue.ForceCleanup();
|
|
|
|
// Exit the try if applicable.
|
|
if (isTryBody)
|
|
ExitCXXTryStmt(*cast<CXXTryStmt>(Body), true);
|
|
}
|
|
|
|
namespace {
|
|
/// Call the operator delete associated with the current destructor.
|
|
struct CallDtorDelete : EHScopeStack::Cleanup {
|
|
CallDtorDelete() {}
|
|
|
|
void Emit(CodeGenFunction &CGF, Flags flags) {
|
|
const CXXDestructorDecl *Dtor = cast<CXXDestructorDecl>(CGF.CurCodeDecl);
|
|
const CXXRecordDecl *ClassDecl = Dtor->getParent();
|
|
CGF.EmitDeleteCall(Dtor->getOperatorDelete(), CGF.LoadCXXThis(),
|
|
CGF.getContext().getTagDeclType(ClassDecl));
|
|
}
|
|
};
|
|
|
|
class DestroyField : public EHScopeStack::Cleanup {
|
|
const FieldDecl *field;
|
|
CodeGenFunction::Destroyer *destroyer;
|
|
bool useEHCleanupForArray;
|
|
|
|
public:
|
|
DestroyField(const FieldDecl *field, CodeGenFunction::Destroyer *destroyer,
|
|
bool useEHCleanupForArray)
|
|
: field(field), destroyer(destroyer),
|
|
useEHCleanupForArray(useEHCleanupForArray) {}
|
|
|
|
void Emit(CodeGenFunction &CGF, Flags flags) {
|
|
// Find the address of the field.
|
|
llvm::Value *thisValue = CGF.LoadCXXThis();
|
|
LValue LV = CGF.EmitLValueForField(thisValue, field, /*CVRQualifiers=*/0);
|
|
assert(LV.isSimple());
|
|
|
|
CGF.emitDestroy(LV.getAddress(), field->getType(), destroyer,
|
|
flags.isForNormalCleanup() && useEHCleanupForArray);
|
|
}
|
|
};
|
|
}
|
|
|
|
/// EmitDtorEpilogue - Emit all code that comes at the end of class's
|
|
/// destructor. This is to call destructors on members and base classes
|
|
/// in reverse order of their construction.
|
|
void CodeGenFunction::EnterDtorCleanups(const CXXDestructorDecl *DD,
|
|
CXXDtorType DtorType) {
|
|
assert(!DD->isTrivial() &&
|
|
"Should not emit dtor epilogue for trivial dtor!");
|
|
|
|
// The deleting-destructor phase just needs to call the appropriate
|
|
// operator delete that Sema picked up.
|
|
if (DtorType == Dtor_Deleting) {
|
|
assert(DD->getOperatorDelete() &&
|
|
"operator delete missing - EmitDtorEpilogue");
|
|
EHStack.pushCleanup<CallDtorDelete>(NormalAndEHCleanup);
|
|
return;
|
|
}
|
|
|
|
const CXXRecordDecl *ClassDecl = DD->getParent();
|
|
|
|
// Unions have no bases and do not call field destructors.
|
|
if (ClassDecl->isUnion())
|
|
return;
|
|
|
|
// The complete-destructor phase just destructs all the virtual bases.
|
|
if (DtorType == Dtor_Complete) {
|
|
|
|
// We push them in the forward order so that they'll be popped in
|
|
// the reverse order.
|
|
for (CXXRecordDecl::base_class_const_iterator I =
|
|
ClassDecl->vbases_begin(), E = ClassDecl->vbases_end();
|
|
I != E; ++I) {
|
|
const CXXBaseSpecifier &Base = *I;
|
|
CXXRecordDecl *BaseClassDecl
|
|
= cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
|
|
|
|
// Ignore trivial destructors.
|
|
if (BaseClassDecl->hasTrivialDestructor())
|
|
continue;
|
|
|
|
EHStack.pushCleanup<CallBaseDtor>(NormalAndEHCleanup,
|
|
BaseClassDecl,
|
|
/*BaseIsVirtual*/ true);
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
assert(DtorType == Dtor_Base);
|
|
|
|
// Destroy non-virtual bases.
|
|
for (CXXRecordDecl::base_class_const_iterator I =
|
|
ClassDecl->bases_begin(), E = ClassDecl->bases_end(); I != E; ++I) {
|
|
const CXXBaseSpecifier &Base = *I;
|
|
|
|
// Ignore virtual bases.
|
|
if (Base.isVirtual())
|
|
continue;
|
|
|
|
CXXRecordDecl *BaseClassDecl = Base.getType()->getAsCXXRecordDecl();
|
|
|
|
// Ignore trivial destructors.
|
|
if (BaseClassDecl->hasTrivialDestructor())
|
|
continue;
|
|
|
|
EHStack.pushCleanup<CallBaseDtor>(NormalAndEHCleanup,
|
|
BaseClassDecl,
|
|
/*BaseIsVirtual*/ false);
|
|
}
|
|
|
|
// Destroy direct fields.
|
|
SmallVector<const FieldDecl *, 16> FieldDecls;
|
|
for (CXXRecordDecl::field_iterator I = ClassDecl->field_begin(),
|
|
E = ClassDecl->field_end(); I != E; ++I) {
|
|
const FieldDecl *field = *I;
|
|
QualType type = field->getType();
|
|
QualType::DestructionKind dtorKind = type.isDestructedType();
|
|
if (!dtorKind) continue;
|
|
|
|
CleanupKind cleanupKind = getCleanupKind(dtorKind);
|
|
EHStack.pushCleanup<DestroyField>(cleanupKind, field,
|
|
getDestroyer(dtorKind),
|
|
cleanupKind & EHCleanup);
|
|
}
|
|
}
|
|
|
|
/// EmitCXXAggrConstructorCall - Emit a loop to call a particular
|
|
/// constructor for each of several members of an array.
|
|
///
|
|
/// \param ctor the constructor to call for each element
|
|
/// \param argBegin,argEnd the arguments to evaluate and pass to the
|
|
/// constructor
|
|
/// \param arrayType the type of the array to initialize
|
|
/// \param arrayBegin an arrayType*
|
|
/// \param zeroInitialize true if each element should be
|
|
/// zero-initialized before it is constructed
|
|
void
|
|
CodeGenFunction::EmitCXXAggrConstructorCall(const CXXConstructorDecl *ctor,
|
|
const ConstantArrayType *arrayType,
|
|
llvm::Value *arrayBegin,
|
|
CallExpr::const_arg_iterator argBegin,
|
|
CallExpr::const_arg_iterator argEnd,
|
|
bool zeroInitialize) {
|
|
QualType elementType;
|
|
llvm::Value *numElements =
|
|
emitArrayLength(arrayType, elementType, arrayBegin);
|
|
|
|
EmitCXXAggrConstructorCall(ctor, numElements, arrayBegin,
|
|
argBegin, argEnd, zeroInitialize);
|
|
}
|
|
|
|
/// EmitCXXAggrConstructorCall - Emit a loop to call a particular
|
|
/// constructor for each of several members of an array.
|
|
///
|
|
/// \param ctor the constructor to call for each element
|
|
/// \param numElements the number of elements in the array;
|
|
/// may be zero
|
|
/// \param argBegin,argEnd the arguments to evaluate and pass to the
|
|
/// constructor
|
|
/// \param arrayBegin a T*, where T is the type constructed by ctor
|
|
/// \param zeroInitialize true if each element should be
|
|
/// zero-initialized before it is constructed
|
|
void
|
|
CodeGenFunction::EmitCXXAggrConstructorCall(const CXXConstructorDecl *ctor,
|
|
llvm::Value *numElements,
|
|
llvm::Value *arrayBegin,
|
|
CallExpr::const_arg_iterator argBegin,
|
|
CallExpr::const_arg_iterator argEnd,
|
|
bool zeroInitialize) {
|
|
|
|
// It's legal for numElements to be zero. This can happen both
|
|
// dynamically, because x can be zero in 'new A[x]', and statically,
|
|
// because of GCC extensions that permit zero-length arrays. There
|
|
// are probably legitimate places where we could assume that this
|
|
// doesn't happen, but it's not clear that it's worth it.
|
|
llvm::BranchInst *zeroCheckBranch = 0;
|
|
|
|
// Optimize for a constant count.
|
|
llvm::ConstantInt *constantCount
|
|
= dyn_cast<llvm::ConstantInt>(numElements);
|
|
if (constantCount) {
|
|
// Just skip out if the constant count is zero.
|
|
if (constantCount->isZero()) return;
|
|
|
|
// Otherwise, emit the check.
|
|
} else {
|
|
llvm::BasicBlock *loopBB = createBasicBlock("new.ctorloop");
|
|
llvm::Value *iszero = Builder.CreateIsNull(numElements, "isempty");
|
|
zeroCheckBranch = Builder.CreateCondBr(iszero, loopBB, loopBB);
|
|
EmitBlock(loopBB);
|
|
}
|
|
|
|
// Find the end of the array.
|
|
llvm::Value *arrayEnd = Builder.CreateInBoundsGEP(arrayBegin, numElements,
|
|
"arrayctor.end");
|
|
|
|
// Enter the loop, setting up a phi for the current location to initialize.
|
|
llvm::BasicBlock *entryBB = Builder.GetInsertBlock();
|
|
llvm::BasicBlock *loopBB = createBasicBlock("arrayctor.loop");
|
|
EmitBlock(loopBB);
|
|
llvm::PHINode *cur = Builder.CreatePHI(arrayBegin->getType(), 2,
|
|
"arrayctor.cur");
|
|
cur->addIncoming(arrayBegin, entryBB);
|
|
|
|
// Inside the loop body, emit the constructor call on the array element.
|
|
|
|
QualType type = getContext().getTypeDeclType(ctor->getParent());
|
|
|
|
// Zero initialize the storage, if requested.
|
|
if (zeroInitialize)
|
|
EmitNullInitialization(cur, type);
|
|
|
|
// C++ [class.temporary]p4:
|
|
// There are two contexts in which temporaries are destroyed at a different
|
|
// point than the end of the full-expression. The first context is when a
|
|
// default constructor is called to initialize an element of an array.
|
|
// If the constructor has one or more default arguments, the destruction of
|
|
// every temporary created in a default argument expression is sequenced
|
|
// before the construction of the next array element, if any.
|
|
|
|
{
|
|
RunCleanupsScope Scope(*this);
|
|
|
|
// Evaluate the constructor and its arguments in a regular
|
|
// partial-destroy cleanup.
|
|
if (getLangOptions().Exceptions &&
|
|
!ctor->getParent()->hasTrivialDestructor()) {
|
|
Destroyer *destroyer = destroyCXXObject;
|
|
pushRegularPartialArrayCleanup(arrayBegin, cur, type, *destroyer);
|
|
}
|
|
|
|
EmitCXXConstructorCall(ctor, Ctor_Complete, /*ForVirtualBase=*/ false,
|
|
cur, argBegin, argEnd);
|
|
}
|
|
|
|
// Go to the next element.
|
|
llvm::Value *next =
|
|
Builder.CreateInBoundsGEP(cur, llvm::ConstantInt::get(SizeTy, 1),
|
|
"arrayctor.next");
|
|
cur->addIncoming(next, Builder.GetInsertBlock());
|
|
|
|
// Check whether that's the end of the loop.
|
|
llvm::Value *done = Builder.CreateICmpEQ(next, arrayEnd, "arrayctor.done");
|
|
llvm::BasicBlock *contBB = createBasicBlock("arrayctor.cont");
|
|
Builder.CreateCondBr(done, contBB, loopBB);
|
|
|
|
// Patch the earlier check to skip over the loop.
|
|
if (zeroCheckBranch) zeroCheckBranch->setSuccessor(0, contBB);
|
|
|
|
EmitBlock(contBB);
|
|
}
|
|
|
|
void CodeGenFunction::destroyCXXObject(CodeGenFunction &CGF,
|
|
llvm::Value *addr,
|
|
QualType type) {
|
|
const RecordType *rtype = type->castAs<RecordType>();
|
|
const CXXRecordDecl *record = cast<CXXRecordDecl>(rtype->getDecl());
|
|
const CXXDestructorDecl *dtor = record->getDestructor();
|
|
assert(!dtor->isTrivial());
|
|
CGF.EmitCXXDestructorCall(dtor, Dtor_Complete, /*for vbase*/ false,
|
|
addr);
|
|
}
|
|
|
|
void
|
|
CodeGenFunction::EmitCXXConstructorCall(const CXXConstructorDecl *D,
|
|
CXXCtorType Type, bool ForVirtualBase,
|
|
llvm::Value *This,
|
|
CallExpr::const_arg_iterator ArgBeg,
|
|
CallExpr::const_arg_iterator ArgEnd) {
|
|
|
|
CGDebugInfo *DI = getDebugInfo();
|
|
if (DI && CGM.getCodeGenOpts().LimitDebugInfo) {
|
|
// If debug info for this class has not been emitted then this is the
|
|
// right time to do so.
|
|
const CXXRecordDecl *Parent = D->getParent();
|
|
DI->getOrCreateRecordType(CGM.getContext().getTypeDeclType(Parent),
|
|
Parent->getLocation());
|
|
}
|
|
|
|
if (D->isTrivial()) {
|
|
if (ArgBeg == ArgEnd) {
|
|
// Trivial default constructor, no codegen required.
|
|
assert(D->isDefaultConstructor() &&
|
|
"trivial 0-arg ctor not a default ctor");
|
|
return;
|
|
}
|
|
|
|
assert(ArgBeg + 1 == ArgEnd && "unexpected argcount for trivial ctor");
|
|
assert(D->isCopyOrMoveConstructor() &&
|
|
"trivial 1-arg ctor not a copy/move ctor");
|
|
|
|
const Expr *E = (*ArgBeg);
|
|
QualType Ty = E->getType();
|
|
llvm::Value *Src = EmitLValue(E).getAddress();
|
|
EmitAggregateCopy(This, Src, Ty);
|
|
return;
|
|
}
|
|
|
|
llvm::Value *VTT = GetVTTParameter(*this, GlobalDecl(D, Type), ForVirtualBase);
|
|
llvm::Value *Callee = CGM.GetAddrOfCXXConstructor(D, Type);
|
|
|
|
EmitCXXMemberCall(D, Callee, ReturnValueSlot(), This, VTT, ArgBeg, ArgEnd);
|
|
}
|
|
|
|
void
|
|
CodeGenFunction::EmitSynthesizedCXXCopyCtorCall(const CXXConstructorDecl *D,
|
|
llvm::Value *This, llvm::Value *Src,
|
|
CallExpr::const_arg_iterator ArgBeg,
|
|
CallExpr::const_arg_iterator ArgEnd) {
|
|
if (D->isTrivial()) {
|
|
assert(ArgBeg + 1 == ArgEnd && "unexpected argcount for trivial ctor");
|
|
assert(D->isCopyOrMoveConstructor() &&
|
|
"trivial 1-arg ctor not a copy/move ctor");
|
|
EmitAggregateCopy(This, Src, (*ArgBeg)->getType());
|
|
return;
|
|
}
|
|
llvm::Value *Callee = CGM.GetAddrOfCXXConstructor(D,
|
|
clang::Ctor_Complete);
|
|
assert(D->isInstance() &&
|
|
"Trying to emit a member call expr on a static method!");
|
|
|
|
const FunctionProtoType *FPT = D->getType()->getAs<FunctionProtoType>();
|
|
|
|
CallArgList Args;
|
|
|
|
// Push the this ptr.
|
|
Args.add(RValue::get(This), D->getThisType(getContext()));
|
|
|
|
|
|
// Push the src ptr.
|
|
QualType QT = *(FPT->arg_type_begin());
|
|
llvm::Type *t = CGM.getTypes().ConvertType(QT);
|
|
Src = Builder.CreateBitCast(Src, t);
|
|
Args.add(RValue::get(Src), QT);
|
|
|
|
// Skip over first argument (Src).
|
|
++ArgBeg;
|
|
CallExpr::const_arg_iterator Arg = ArgBeg;
|
|
for (FunctionProtoType::arg_type_iterator I = FPT->arg_type_begin()+1,
|
|
E = FPT->arg_type_end(); I != E; ++I, ++Arg) {
|
|
assert(Arg != ArgEnd && "Running over edge of argument list!");
|
|
EmitCallArg(Args, *Arg, *I);
|
|
}
|
|
// Either we've emitted all the call args, or we have a call to a
|
|
// variadic function.
|
|
assert((Arg == ArgEnd || FPT->isVariadic()) &&
|
|
"Extra arguments in non-variadic function!");
|
|
// If we still have any arguments, emit them using the type of the argument.
|
|
for (; Arg != ArgEnd; ++Arg) {
|
|
QualType ArgType = Arg->getType();
|
|
EmitCallArg(Args, *Arg, ArgType);
|
|
}
|
|
|
|
EmitCall(CGM.getTypes().getFunctionInfo(Args, FPT), Callee,
|
|
ReturnValueSlot(), Args, D);
|
|
}
|
|
|
|
void
|
|
CodeGenFunction::EmitDelegateCXXConstructorCall(const CXXConstructorDecl *Ctor,
|
|
CXXCtorType CtorType,
|
|
const FunctionArgList &Args) {
|
|
CallArgList DelegateArgs;
|
|
|
|
FunctionArgList::const_iterator I = Args.begin(), E = Args.end();
|
|
assert(I != E && "no parameters to constructor");
|
|
|
|
// this
|
|
DelegateArgs.add(RValue::get(LoadCXXThis()), (*I)->getType());
|
|
++I;
|
|
|
|
// vtt
|
|
if (llvm::Value *VTT = GetVTTParameter(*this, GlobalDecl(Ctor, CtorType),
|
|
/*ForVirtualBase=*/false)) {
|
|
QualType VoidPP = getContext().getPointerType(getContext().VoidPtrTy);
|
|
DelegateArgs.add(RValue::get(VTT), VoidPP);
|
|
|
|
if (CodeGenVTables::needsVTTParameter(CurGD)) {
|
|
assert(I != E && "cannot skip vtt parameter, already done with args");
|
|
assert((*I)->getType() == VoidPP && "skipping parameter not of vtt type");
|
|
++I;
|
|
}
|
|
}
|
|
|
|
// Explicit arguments.
|
|
for (; I != E; ++I) {
|
|
const VarDecl *param = *I;
|
|
EmitDelegateCallArg(DelegateArgs, param);
|
|
}
|
|
|
|
EmitCall(CGM.getTypes().getFunctionInfo(Ctor, CtorType),
|
|
CGM.GetAddrOfCXXConstructor(Ctor, CtorType),
|
|
ReturnValueSlot(), DelegateArgs, Ctor);
|
|
}
|
|
|
|
namespace {
|
|
struct CallDelegatingCtorDtor : EHScopeStack::Cleanup {
|
|
const CXXDestructorDecl *Dtor;
|
|
llvm::Value *Addr;
|
|
CXXDtorType Type;
|
|
|
|
CallDelegatingCtorDtor(const CXXDestructorDecl *D, llvm::Value *Addr,
|
|
CXXDtorType Type)
|
|
: Dtor(D), Addr(Addr), Type(Type) {}
|
|
|
|
void Emit(CodeGenFunction &CGF, Flags flags) {
|
|
CGF.EmitCXXDestructorCall(Dtor, Type, /*ForVirtualBase=*/false,
|
|
Addr);
|
|
}
|
|
};
|
|
}
|
|
|
|
void
|
|
CodeGenFunction::EmitDelegatingCXXConstructorCall(const CXXConstructorDecl *Ctor,
|
|
const FunctionArgList &Args) {
|
|
assert(Ctor->isDelegatingConstructor());
|
|
|
|
llvm::Value *ThisPtr = LoadCXXThis();
|
|
|
|
QualType Ty = getContext().getTagDeclType(Ctor->getParent());
|
|
CharUnits Alignment = getContext().getTypeAlignInChars(Ty);
|
|
AggValueSlot AggSlot =
|
|
AggValueSlot::forAddr(ThisPtr, Alignment, Qualifiers(),
|
|
AggValueSlot::IsDestructed,
|
|
AggValueSlot::DoesNotNeedGCBarriers,
|
|
AggValueSlot::IsNotAliased);
|
|
|
|
EmitAggExpr(Ctor->init_begin()[0]->getInit(), AggSlot);
|
|
|
|
const CXXRecordDecl *ClassDecl = Ctor->getParent();
|
|
if (CGM.getLangOptions().Exceptions && !ClassDecl->hasTrivialDestructor()) {
|
|
CXXDtorType Type =
|
|
CurGD.getCtorType() == Ctor_Complete ? Dtor_Complete : Dtor_Base;
|
|
|
|
EHStack.pushCleanup<CallDelegatingCtorDtor>(EHCleanup,
|
|
ClassDecl->getDestructor(),
|
|
ThisPtr, Type);
|
|
}
|
|
}
|
|
|
|
void CodeGenFunction::EmitCXXDestructorCall(const CXXDestructorDecl *DD,
|
|
CXXDtorType Type,
|
|
bool ForVirtualBase,
|
|
llvm::Value *This) {
|
|
llvm::Value *VTT = GetVTTParameter(*this, GlobalDecl(DD, Type),
|
|
ForVirtualBase);
|
|
llvm::Value *Callee = 0;
|
|
if (getContext().getLangOptions().AppleKext)
|
|
Callee = BuildAppleKextVirtualDestructorCall(DD, Type,
|
|
DD->getParent());
|
|
|
|
if (!Callee)
|
|
Callee = CGM.GetAddrOfCXXDestructor(DD, Type);
|
|
|
|
EmitCXXMemberCall(DD, Callee, ReturnValueSlot(), This, VTT, 0, 0);
|
|
}
|
|
|
|
namespace {
|
|
struct CallLocalDtor : EHScopeStack::Cleanup {
|
|
const CXXDestructorDecl *Dtor;
|
|
llvm::Value *Addr;
|
|
|
|
CallLocalDtor(const CXXDestructorDecl *D, llvm::Value *Addr)
|
|
: Dtor(D), Addr(Addr) {}
|
|
|
|
void Emit(CodeGenFunction &CGF, Flags flags) {
|
|
CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete,
|
|
/*ForVirtualBase=*/false, Addr);
|
|
}
|
|
};
|
|
}
|
|
|
|
void CodeGenFunction::PushDestructorCleanup(const CXXDestructorDecl *D,
|
|
llvm::Value *Addr) {
|
|
EHStack.pushCleanup<CallLocalDtor>(NormalAndEHCleanup, D, Addr);
|
|
}
|
|
|
|
void CodeGenFunction::PushDestructorCleanup(QualType T, llvm::Value *Addr) {
|
|
CXXRecordDecl *ClassDecl = T->getAsCXXRecordDecl();
|
|
if (!ClassDecl) return;
|
|
if (ClassDecl->hasTrivialDestructor()) return;
|
|
|
|
const CXXDestructorDecl *D = ClassDecl->getDestructor();
|
|
assert(D && D->isUsed() && "destructor not marked as used!");
|
|
PushDestructorCleanup(D, Addr);
|
|
}
|
|
|
|
llvm::Value *
|
|
CodeGenFunction::GetVirtualBaseClassOffset(llvm::Value *This,
|
|
const CXXRecordDecl *ClassDecl,
|
|
const CXXRecordDecl *BaseClassDecl) {
|
|
llvm::Value *VTablePtr = GetVTablePtr(This, Int8PtrTy);
|
|
CharUnits VBaseOffsetOffset =
|
|
CGM.getVTableContext().getVirtualBaseOffsetOffset(ClassDecl, BaseClassDecl);
|
|
|
|
llvm::Value *VBaseOffsetPtr =
|
|
Builder.CreateConstGEP1_64(VTablePtr, VBaseOffsetOffset.getQuantity(),
|
|
"vbase.offset.ptr");
|
|
llvm::Type *PtrDiffTy =
|
|
ConvertType(getContext().getPointerDiffType());
|
|
|
|
VBaseOffsetPtr = Builder.CreateBitCast(VBaseOffsetPtr,
|
|
PtrDiffTy->getPointerTo());
|
|
|
|
llvm::Value *VBaseOffset = Builder.CreateLoad(VBaseOffsetPtr, "vbase.offset");
|
|
|
|
return VBaseOffset;
|
|
}
|
|
|
|
void
|
|
CodeGenFunction::InitializeVTablePointer(BaseSubobject Base,
|
|
const CXXRecordDecl *NearestVBase,
|
|
CharUnits OffsetFromNearestVBase,
|
|
llvm::Constant *VTable,
|
|
const CXXRecordDecl *VTableClass) {
|
|
const CXXRecordDecl *RD = Base.getBase();
|
|
|
|
// Compute the address point.
|
|
llvm::Value *VTableAddressPoint;
|
|
|
|
// Check if we need to use a vtable from the VTT.
|
|
if (CodeGenVTables::needsVTTParameter(CurGD) &&
|
|
(RD->getNumVBases() || NearestVBase)) {
|
|
// Get the secondary vpointer index.
|
|
uint64_t VirtualPointerIndex =
|
|
CGM.getVTables().getSecondaryVirtualPointerIndex(VTableClass, Base);
|
|
|
|
/// Load the VTT.
|
|
llvm::Value *VTT = LoadCXXVTT();
|
|
if (VirtualPointerIndex)
|
|
VTT = Builder.CreateConstInBoundsGEP1_64(VTT, VirtualPointerIndex);
|
|
|
|
// And load the address point from the VTT.
|
|
VTableAddressPoint = Builder.CreateLoad(VTT);
|
|
} else {
|
|
uint64_t AddressPoint =
|
|
CGM.getVTableContext().getVTableLayout(VTableClass).getAddressPoint(Base);
|
|
VTableAddressPoint =
|
|
Builder.CreateConstInBoundsGEP2_64(VTable, 0, AddressPoint);
|
|
}
|
|
|
|
// Compute where to store the address point.
|
|
llvm::Value *VirtualOffset = 0;
|
|
CharUnits NonVirtualOffset = CharUnits::Zero();
|
|
|
|
if (CodeGenVTables::needsVTTParameter(CurGD) && NearestVBase) {
|
|
// We need to use the virtual base offset offset because the virtual base
|
|
// might have a different offset in the most derived class.
|
|
VirtualOffset = GetVirtualBaseClassOffset(LoadCXXThis(), VTableClass,
|
|
NearestVBase);
|
|
NonVirtualOffset = OffsetFromNearestVBase;
|
|
} else {
|
|
// We can just use the base offset in the complete class.
|
|
NonVirtualOffset = Base.getBaseOffset();
|
|
}
|
|
|
|
// Apply the offsets.
|
|
llvm::Value *VTableField = LoadCXXThis();
|
|
|
|
if (!NonVirtualOffset.isZero() || VirtualOffset)
|
|
VTableField = ApplyNonVirtualAndVirtualOffset(*this, VTableField,
|
|
NonVirtualOffset,
|
|
VirtualOffset);
|
|
|
|
// Finally, store the address point.
|
|
llvm::Type *AddressPointPtrTy =
|
|
VTableAddressPoint->getType()->getPointerTo();
|
|
VTableField = Builder.CreateBitCast(VTableField, AddressPointPtrTy);
|
|
Builder.CreateStore(VTableAddressPoint, VTableField);
|
|
}
|
|
|
|
void
|
|
CodeGenFunction::InitializeVTablePointers(BaseSubobject Base,
|
|
const CXXRecordDecl *NearestVBase,
|
|
CharUnits OffsetFromNearestVBase,
|
|
bool BaseIsNonVirtualPrimaryBase,
|
|
llvm::Constant *VTable,
|
|
const CXXRecordDecl *VTableClass,
|
|
VisitedVirtualBasesSetTy& VBases) {
|
|
// If this base is a non-virtual primary base the address point has already
|
|
// been set.
|
|
if (!BaseIsNonVirtualPrimaryBase) {
|
|
// Initialize the vtable pointer for this base.
|
|
InitializeVTablePointer(Base, NearestVBase, OffsetFromNearestVBase,
|
|
VTable, VTableClass);
|
|
}
|
|
|
|
const CXXRecordDecl *RD = Base.getBase();
|
|
|
|
// Traverse bases.
|
|
for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
|
|
E = RD->bases_end(); I != E; ++I) {
|
|
CXXRecordDecl *BaseDecl
|
|
= cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
|
|
|
|
// Ignore classes without a vtable.
|
|
if (!BaseDecl->isDynamicClass())
|
|
continue;
|
|
|
|
CharUnits BaseOffset;
|
|
CharUnits BaseOffsetFromNearestVBase;
|
|
bool BaseDeclIsNonVirtualPrimaryBase;
|
|
|
|
if (I->isVirtual()) {
|
|
// Check if we've visited this virtual base before.
|
|
if (!VBases.insert(BaseDecl))
|
|
continue;
|
|
|
|
const ASTRecordLayout &Layout =
|
|
getContext().getASTRecordLayout(VTableClass);
|
|
|
|
BaseOffset = Layout.getVBaseClassOffset(BaseDecl);
|
|
BaseOffsetFromNearestVBase = CharUnits::Zero();
|
|
BaseDeclIsNonVirtualPrimaryBase = false;
|
|
} else {
|
|
const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
|
|
|
|
BaseOffset = Base.getBaseOffset() + Layout.getBaseClassOffset(BaseDecl);
|
|
BaseOffsetFromNearestVBase =
|
|
OffsetFromNearestVBase + Layout.getBaseClassOffset(BaseDecl);
|
|
BaseDeclIsNonVirtualPrimaryBase = Layout.getPrimaryBase() == BaseDecl;
|
|
}
|
|
|
|
InitializeVTablePointers(BaseSubobject(BaseDecl, BaseOffset),
|
|
I->isVirtual() ? BaseDecl : NearestVBase,
|
|
BaseOffsetFromNearestVBase,
|
|
BaseDeclIsNonVirtualPrimaryBase,
|
|
VTable, VTableClass, VBases);
|
|
}
|
|
}
|
|
|
|
void CodeGenFunction::InitializeVTablePointers(const CXXRecordDecl *RD) {
|
|
// Ignore classes without a vtable.
|
|
if (!RD->isDynamicClass())
|
|
return;
|
|
|
|
// Get the VTable.
|
|
llvm::Constant *VTable = CGM.getVTables().GetAddrOfVTable(RD);
|
|
|
|
// Initialize the vtable pointers for this class and all of its bases.
|
|
VisitedVirtualBasesSetTy VBases;
|
|
InitializeVTablePointers(BaseSubobject(RD, CharUnits::Zero()),
|
|
/*NearestVBase=*/0,
|
|
/*OffsetFromNearestVBase=*/CharUnits::Zero(),
|
|
/*BaseIsNonVirtualPrimaryBase=*/false,
|
|
VTable, RD, VBases);
|
|
}
|
|
|
|
llvm::Value *CodeGenFunction::GetVTablePtr(llvm::Value *This,
|
|
llvm::Type *Ty) {
|
|
llvm::Value *VTablePtrSrc = Builder.CreateBitCast(This, Ty->getPointerTo());
|
|
return Builder.CreateLoad(VTablePtrSrc, "vtable");
|
|
}
|
|
|
|
static const CXXRecordDecl *getMostDerivedClassDecl(const Expr *Base) {
|
|
const Expr *E = Base;
|
|
|
|
while (true) {
|
|
E = E->IgnoreParens();
|
|
if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
|
|
if (CE->getCastKind() == CK_DerivedToBase ||
|
|
CE->getCastKind() == CK_UncheckedDerivedToBase ||
|
|
CE->getCastKind() == CK_NoOp) {
|
|
E = CE->getSubExpr();
|
|
continue;
|
|
}
|
|
}
|
|
|
|
break;
|
|
}
|
|
|
|
QualType DerivedType = E->getType();
|
|
if (const PointerType *PTy = DerivedType->getAs<PointerType>())
|
|
DerivedType = PTy->getPointeeType();
|
|
|
|
return cast<CXXRecordDecl>(DerivedType->castAs<RecordType>()->getDecl());
|
|
}
|
|
|
|
// FIXME: Ideally Expr::IgnoreParenNoopCasts should do this, but it doesn't do
|
|
// quite what we want.
|
|
static const Expr *skipNoOpCastsAndParens(const Expr *E) {
|
|
while (true) {
|
|
if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
|
|
E = PE->getSubExpr();
|
|
continue;
|
|
}
|
|
|
|
if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
|
|
if (CE->getCastKind() == CK_NoOp) {
|
|
E = CE->getSubExpr();
|
|
continue;
|
|
}
|
|
}
|
|
if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
|
|
if (UO->getOpcode() == UO_Extension) {
|
|
E = UO->getSubExpr();
|
|
continue;
|
|
}
|
|
}
|
|
return E;
|
|
}
|
|
}
|
|
|
|
/// canDevirtualizeMemberFunctionCall - Checks whether the given virtual member
|
|
/// function call on the given expr can be devirtualized.
|
|
static bool canDevirtualizeMemberFunctionCall(const Expr *Base,
|
|
const CXXMethodDecl *MD) {
|
|
// If the most derived class is marked final, we know that no subclass can
|
|
// override this member function and so we can devirtualize it. For example:
|
|
//
|
|
// struct A { virtual void f(); }
|
|
// struct B final : A { };
|
|
//
|
|
// void f(B *b) {
|
|
// b->f();
|
|
// }
|
|
//
|
|
const CXXRecordDecl *MostDerivedClassDecl = getMostDerivedClassDecl(Base);
|
|
if (MostDerivedClassDecl->hasAttr<FinalAttr>())
|
|
return true;
|
|
|
|
// If the member function is marked 'final', we know that it can't be
|
|
// overridden and can therefore devirtualize it.
|
|
if (MD->hasAttr<FinalAttr>())
|
|
return true;
|
|
|
|
// Similarly, if the class itself is marked 'final' it can't be overridden
|
|
// and we can therefore devirtualize the member function call.
|
|
if (MD->getParent()->hasAttr<FinalAttr>())
|
|
return true;
|
|
|
|
Base = skipNoOpCastsAndParens(Base);
|
|
if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base)) {
|
|
if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) {
|
|
// This is a record decl. We know the type and can devirtualize it.
|
|
return VD->getType()->isRecordType();
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
// We can always devirtualize calls on temporary object expressions.
|
|
if (isa<CXXConstructExpr>(Base))
|
|
return true;
|
|
|
|
// And calls on bound temporaries.
|
|
if (isa<CXXBindTemporaryExpr>(Base))
|
|
return true;
|
|
|
|
// Check if this is a call expr that returns a record type.
|
|
if (const CallExpr *CE = dyn_cast<CallExpr>(Base))
|
|
return CE->getCallReturnType()->isRecordType();
|
|
|
|
// We can't devirtualize the call.
|
|
return false;
|
|
}
|
|
|
|
static bool UseVirtualCall(ASTContext &Context,
|
|
const CXXOperatorCallExpr *CE,
|
|
const CXXMethodDecl *MD) {
|
|
if (!MD->isVirtual())
|
|
return false;
|
|
|
|
// When building with -fapple-kext, all calls must go through the vtable since
|
|
// the kernel linker can do runtime patching of vtables.
|
|
if (Context.getLangOptions().AppleKext)
|
|
return true;
|
|
|
|
return !canDevirtualizeMemberFunctionCall(CE->getArg(0), MD);
|
|
}
|
|
|
|
llvm::Value *
|
|
CodeGenFunction::EmitCXXOperatorMemberCallee(const CXXOperatorCallExpr *E,
|
|
const CXXMethodDecl *MD,
|
|
llvm::Value *This) {
|
|
const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
|
|
llvm::Type *Ty =
|
|
CGM.getTypes().GetFunctionType(CGM.getTypes().getFunctionInfo(MD),
|
|
FPT->isVariadic());
|
|
|
|
if (UseVirtualCall(getContext(), E, MD))
|
|
return BuildVirtualCall(MD, This, Ty);
|
|
|
|
return CGM.GetAddrOfFunction(MD, Ty);
|
|
}
|