Factor out the code for emitting code to load vtable pointer members
so that it's done in one place.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@117386 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGCXX.cpp b/lib/CodeGen/CGCXX.cpp
index 02cd8f8..15d1469 100644
--- a/lib/CodeGen/CGCXX.cpp
+++ b/lib/CodeGen/CGCXX.cpp
@@ -289,11 +289,9 @@
static llvm::Value *BuildVirtualCall(CodeGenFunction &CGF, uint64_t VTableIndex,
llvm::Value *This, const llvm::Type *Ty) {
- Ty = Ty->getPointerTo()->getPointerTo()->getPointerTo();
+ Ty = Ty->getPointerTo()->getPointerTo();
- llvm::Value *VTable = CGF.Builder.CreateBitCast(This, Ty);
- VTable = CGF.Builder.CreateLoad(VTable);
-
+ llvm::Value *VTable = CGF.GetVTablePtr(This, Ty);
llvm::Value *VFuncPtr =
CGF.Builder.CreateConstInBoundsGEP1_64(VTable, VTableIndex, "vfn");
return CGF.Builder.CreateLoad(VFuncPtr);
diff --git a/lib/CodeGen/CGClass.cpp b/lib/CodeGen/CGClass.cpp
index 33d1f6e..ebc8442 100644
--- a/lib/CodeGen/CGClass.cpp
+++ b/lib/CodeGen/CGClass.cpp
@@ -1237,10 +1237,7 @@
const llvm::Type *Int8PtrTy =
llvm::Type::getInt8Ty(VMContext)->getPointerTo();
- llvm::Value *VTablePtr = Builder.CreateBitCast(This,
- Int8PtrTy->getPointerTo());
- VTablePtr = Builder.CreateLoad(VTablePtr, "vtable");
-
+ llvm::Value *VTablePtr = GetVTablePtr(This, Int8PtrTy);
int64_t VBaseOffsetOffset =
CGM.getVTables().getVirtualBaseOffsetOffset(ClassDecl, BaseClassDecl);
@@ -1393,3 +1390,9 @@
/*BaseIsNonVirtualPrimaryBase=*/false,
VTable, RD, VBases);
}
+
+llvm::Value *CodeGenFunction::GetVTablePtr(llvm::Value *This,
+ const llvm::Type *Ty) {
+ llvm::Value *VTablePtrSrc = Builder.CreateBitCast(This, Ty->getPointerTo());
+ return Builder.CreateLoad(VTablePtrSrc, "vtable");
+}
diff --git a/lib/CodeGen/CGExprCXX.cpp b/lib/CodeGen/CGExprCXX.cpp
index 2a88d33..750e609 100644
--- a/lib/CodeGen/CGExprCXX.cpp
+++ b/lib/CodeGen/CGExprCXX.cpp
@@ -1348,8 +1348,6 @@
// FIXME: if subE is an lvalue do
LValue Obj = EmitLValue(subE);
llvm::Value *This = Obj.getAddress();
- LTy = LTy->getPointerTo()->getPointerTo();
- llvm::Value *V = Builder.CreateBitCast(This, LTy);
// We need to do a zero check for *p, unless it has NonNullAttr.
// FIXME: PointerType->hasAttr<NonNullAttr>()
bool CanBeZero = false;
@@ -1360,8 +1358,8 @@
llvm::BasicBlock *NonZeroBlock = createBasicBlock();
llvm::BasicBlock *ZeroBlock = createBasicBlock();
- llvm::Value *Zero = llvm::Constant::getNullValue(LTy);
- Builder.CreateCondBr(Builder.CreateICmpNE(V, Zero),
+ llvm::Value *Zero = llvm::Constant::getNullValue(This->getType());
+ Builder.CreateCondBr(Builder.CreateICmpNE(This, Zero),
NonZeroBlock, ZeroBlock);
EmitBlock(ZeroBlock);
/// Call __cxa_bad_typeid
@@ -1373,7 +1371,7 @@
Builder.CreateUnreachable();
EmitBlock(NonZeroBlock);
}
- V = Builder.CreateLoad(V, "vtable");
+ llvm::Value *V = GetVTablePtr(This, LTy->getPointerTo());
V = Builder.CreateConstInBoundsGEP1_64(V, -1ULL);
V = Builder.CreateLoad(V);
return V;
@@ -1430,8 +1428,7 @@
// See if this is a dynamic_cast(void*)
if (ToVoid) {
llvm::Value *This = V;
- V = Builder.CreateBitCast(This, PtrDiffTy->getPointerTo()->getPointerTo());
- V = Builder.CreateLoad(V, "vtable");
+ V = GetVTablePtr(This, PtrDiffTy->getPointerTo());
V = Builder.CreateConstInBoundsGEP1_64(V, -2ULL);
V = Builder.CreateLoad(V, "offset to top");
This = Builder.CreateBitCast(This, llvm::Type::getInt8PtrTy(VMContext));
diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index e02cedd..53056bc 100644
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -888,6 +888,9 @@
void InitializeVTablePointers(const CXXRecordDecl *ClassDecl);
+ /// GetVTablePtr - Return the Value of the vtable pointer member pointed
+ /// to by This.
+ llvm::Value *GetVTablePtr(llvm::Value *This, const llvm::Type *Ty);
/// EnterDtorCleanups - Enter the cleanups necessary to complete the
/// given phase of destruction for a destructor. The end result