PR rtl-optimization/33648

[pf3gnuchains/gcc-fork.git] / gcc / c-gimplify.c

diff --git a/gcc/c-gimplify.c b/gcc/c-gimplify.c
index 9721b67..a1ee27b 100644 (file)
--- a/gcc/c-gimplify.c
+++ b/gcc/c-gimplify.c
@@ -233,6 +233,29 @@ c_gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p ATTRIBUTE_UNUSED)
     case COMPOUND_LITERAL_EXPR:
       return gimplify_compound_literal_expr (expr_p, pre_p);
 
+    case INIT_EXPR:
+    case MODIFY_EXPR:
+      if (TREE_CODE (TREE_OPERAND (*expr_p, 1)) == COMPOUND_LITERAL_EXPR)
+       {
+         tree complit = TREE_OPERAND (*expr_p, 1);
+         tree decl_s = COMPOUND_LITERAL_EXPR_DECL_STMT (complit);
+         tree decl = DECL_EXPR_DECL (decl_s);
+         tree init = DECL_INITIAL (decl);
+
+         /* struct T x = (struct T) { 0, 1, 2 } can be optimized
+            into struct T x = { 0, 1, 2 } if the address of the
+            compound literal has never been taken.  */
+         if (!TREE_ADDRESSABLE (complit)
+             && !TREE_ADDRESSABLE (decl)
+             && init)
+           {
+             *expr_p = copy_node (*expr_p);
+             TREE_OPERAND (*expr_p, 1) = init;
+             return GS_OK;
+           }
+       }
+      return GS_UNHANDLED;
+
     default:
       return GS_UNHANDLED;
     }