Fix two bugs with temporaries:

1. For 

A f() {
	return A();
}

we were incorrectly calling the A destructor on the returned object.

2. For

void f(A);
void g() {
	A a;
	f(a);
}

we were incorrectly not calling the copy constructor.

llvm-svn: 87082

clang/lib/CodeGen/CGCXX.cpp

@@ -671,8 +671,13 @@ CodeGenFunction::EmitCXXConstructExpr(llvm::Value *Dest,
   // Code gen optimization to eliminate copy constructor and return
   // its first argument instead.
   if (getContext().getLangOptions().ElideConstructors && E->isElidable()) {
-    CXXConstructExpr::const_arg_iterator i = E->arg_begin();
-    EmitAggExpr((*i), Dest, false);
+    const Expr *Arg = E->getArg(0);
+    
+    if (const CXXBindTemporaryExpr *BindExpr = 
+          dyn_cast<CXXBindTemporaryExpr>(Arg))
+      Arg = BindExpr->getSubExpr();
+
+    EmitAggExpr(Arg, Dest, false);
     return;
   }
   if (Array) {

clang/lib/Sema/SemaExpr.cpp

@@ -2652,6 +2652,8 @@ Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn,
       // Pass the argument.
       if (PerformCopyInitialization(Arg, ProtoArgType, "passing"))
         return true;
+      
+      Arg = MaybeBindToTemporary(Arg).takeAs<Expr>();
     } else {
       ParmVarDecl *Param = FDecl->getParamDecl(i);
 

clang/test/CodeGenCXX/temporaries.cpp

@@ -162,6 +162,29 @@ C::C()
   
   // CHECK: call void @_ZN6PR50771BD1Ev
 }
-
-
+}
+
+A f8() {
+  // CHECK: call void @_ZN1AC1Ev
+  // CHECK-NOT: call void @_ZN1AD1Ev
+  return A();
+  // CHECK: ret void
+}
+
+struct H {
+  H();
+  ~H();
+  H(const H&);
+};
+
+void f9(H h) {
+  // CHECK: call void @_ZN1HC1Ev
+  // CHECK: call void @_Z2f91H
+  // CHECK: call void @_ZN1HD1Ev
+  f9(H());
+  
+  // CHECK: call void @_ZN1HC1ERKS_
+  // CHECK: call void @_Z2f91H
+  // CHECK: call void @_ZN1HD1Ev
+  f9(h);
 }