When doing a base-to-derived cast we don't need to null check the derived value if the class offset is 0.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@94939 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGClass.cpp b/lib/CodeGen/CGClass.cpp
index 18d33ad..eaebf14 100644
--- a/lib/CodeGen/CGClass.cpp
+++ b/lib/CodeGen/CGClass.cpp
@@ -224,6 +224,14 @@
return Builder.CreateBitCast(Value, DerivedPtrTy);
}
+ llvm::Value *NonVirtualOffset =
+ CGM.GetNonVirtualBaseClassOffset(DerivedClass, Class);
+
+ if (!NonVirtualOffset) {
+ // No offset, we can just cast back.
+ return Builder.CreateBitCast(Value, DerivedPtrTy);
+ }
+
llvm::BasicBlock *CastNull = 0;
llvm::BasicBlock *CastNotNull = 0;
llvm::BasicBlock *CastEnd = 0;
@@ -240,16 +248,13 @@
EmitBlock(CastNotNull);
}
- if (llvm::Value *NonVirtualOffset =
- CGM.GetNonVirtualBaseClassOffset(DerivedClass, Class)) {
- // Apply the offset.
- Value = Builder.CreatePtrToInt(Value, NonVirtualOffset->getType());
- Value = Builder.CreateSub(Value, NonVirtualOffset);
- Value = Builder.CreateIntToPtr(Value, DerivedPtrTy);
- } else {
- // Just cast.
- Value = Builder.CreateBitCast(Value, DerivedPtrTy);
- }
+ // Apply the offset.
+ Value = Builder.CreatePtrToInt(Value, NonVirtualOffset->getType());
+ Value = Builder.CreateSub(Value, NonVirtualOffset);
+ Value = Builder.CreateIntToPtr(Value, DerivedPtrTy);
+
+ // Just cast.
+ Value = Builder.CreateBitCast(Value, DerivedPtrTy);
if (NullCheckValue) {
Builder.CreateBr(CastEnd);