Introduce a new kind of derived-to-base cast which bypasses the need for
null checks, and make sure we elide null checks when accessing base class
members.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@99963 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGExpr.cpp b/lib/CodeGen/CGExpr.cpp
index 2ddc08a..027264f 100644
--- a/lib/CodeGen/CGExpr.cpp
+++ b/lib/CodeGen/CGExpr.cpp
@@ -1637,6 +1637,7 @@
case CastExpr::CK_AnyPointerToObjCPointerCast:
return EmitLValue(E->getSubExpr());
+ case CastExpr::CK_UncheckedDerivedToBase:
case CastExpr::CK_DerivedToBase: {
const RecordType *DerivedClassTy =
E->getSubExpr()->getType()->getAs<RecordType>();
diff --git a/lib/CodeGen/CGExprScalar.cpp b/lib/CodeGen/CGExprScalar.cpp
index 1ef06cc..42bf68e 100644
--- a/lib/CodeGen/CGExprScalar.cpp
+++ b/lib/CodeGen/CGExprScalar.cpp
@@ -769,6 +769,9 @@
static bool ShouldNullCheckClassCastValue(const CastExpr *CE) {
const Expr *E = CE->getSubExpr();
+
+ if (CE->getCastKind() == CastExpr::CK_UncheckedDerivedToBase)
+ return false;
if (isa<CXXThisExpr>(E)) {
// We always assume that 'this' is never null.
@@ -826,6 +829,7 @@
return CGF.GetAddressOfDerivedClass(Src, BaseClassDecl, DerivedClassDecl,
NullCheckValue);
}
+ case CastExpr::CK_UncheckedDerivedToBase:
case CastExpr::CK_DerivedToBase: {
const RecordType *DerivedClassTy =
E->getType()->getAs<PointerType>()->getPointeeType()->getAs<RecordType>();