When performing a derived-to-base cast on the right-hand side of the

synthesized move assignment within an implicitly-defined move
assignment operator, be sure to treat the derived-to-base cast as an
xvalue (rather than an lvalue). Otherwise, we'll end up getting the
wrong constructor.

Optimize a direct call to a trivial move assignment operator to an
aggregate copy, as we do for trivial copy assignment operators, and
update the the assertion in CodeGenFunction::EmitAggregateCopy() to
cope with this optimization.

Fixes PR10860.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@139143 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 10 deletions

diff --git a/lib/CodeGen/CGExprCXX.cpp b/lib/CodeGen/CGExprCXX.cpp
index acc9a2b036..9f21abd20c 100644
--- a/lib/CodeGen/CGExprCXX.cpp
+++ b/lib/CodeGen/CGExprCXX.cpp
@@ -334,16 +334,12 @@ CodeGenFunction::EmitCXXOperatorMemberCallExpr(const CXXOperatorCallExpr *E,
   LValue LV = EmitLValue(E->getArg(0));
   llvm::Value *This = LV.getAddress();
 
-  if (MD->isCopyAssignmentOperator()) {
-    const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(MD->getDeclContext());
-    if (ClassDecl->hasTrivialCopyAssignment()) {
-      assert(!ClassDecl->hasUserDeclaredCopyAssignment() &&
-             "EmitCXXOperatorMemberCallExpr - user declared copy assignment");
-      llvm::Value *Src = EmitLValue(E->getArg(1)).getAddress();
-      QualType Ty = E->getType();
-      EmitAggregateCopy(This, Src, Ty);
-      return RValue::get(This);
-    }
+  if ((MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator()) &&
+      MD->isTrivial()) {
+    llvm::Value *Src = EmitLValue(E->getArg(1)).getAddress();
+    QualType Ty = E->getType();
+    EmitAggregateCopy(This, Src, Ty);
+    return RValue::get(This);
   }
 
   llvm::Value *Callee = EmitCXXOperatorMemberCallee(E, MD, This);