gigi.h (gnat_useless_type_conversion): Declare.

	* gcc-interface/gigi.h (gnat_useless_type_conversion): Declare.
	(rest_of_subprog_body_compilation): Likewise.
	* gcc-interface/decl.c (gnat_to_gnu_entity) <E_Variable>: For renaming,
	test for useless conversions by means of gnat_useless_type_conversion.
	* gcc-interface/trans.c: Include bitmap.h and cgraph.h.
	(language_function): Add named_ret_val and other_ret_val.
	(f_named_ret_val): New macro.
	(f_other_ret_val): Likewise.
	(gigi): Call rest_of_subprog_body_compilation.
	(struct nrv_data): New structure.
	(is_nrv_p): New predicate.
	(prune_nrv_r): New helper function.
	(prune_nrv_in_block): New function.
	(finalize_nrv_r): New helper function.
	(finalize_nrv): New function.
	(return_value_ok_for_nrv_p): New predicate.
	(build_return_expr): If optimization is enabled, record candidates for
	the Named Return Value optimization.
	(build_function_stub): Call rest_of_subprog_body_compilation.
	(Subprogram_Body_to_gnu): If optimization is enabled and there are
	candidates, finalize the Named Return Value optimization.
	Call rest_of_subprog_body_compilation.
	(call_to_gnu): At the end, if a return value is needed, simplify the
	result before wrapping it up in a COMPOUND_EXPR.
	* gcc-interface/utils.c (end_subprog_body): Split into...
	(rest_of_subprog_body_compilation): ...this.  New function.
	(gnat_useless_type_conversion): Likewise.

From-SVN: r179650

1 files changed, 25 insertions, 5 deletions

diff --git a/gcc/ada/gcc-interface/utils.c b/gcc/ada/gcc-interface/utils.c
index feae636..62d9d67 100644
--- a/gcc/ada/gcc-interface/utils.c
+++ b/gcc/ada/gcc-interface/utils.c
@@ -1958,7 +1958,7 @@ begin_subprog_body (tree subprog_decl)
   make_decl_rtl (subprog_decl);
 }
 
-/* Finish the definition of the current subprogram BODY and finalize it.  */
+/* Finish translating the current subprogram and set its BODY.  */
 
 void
 end_subprog_body (tree body)
@@ -1983,7 +1983,13 @@ end_subprog_body (tree body)
   DECL_SAVED_TREE (fndecl) = body;
 
   current_function_decl = DECL_CONTEXT (fndecl);
+}
+
+/* Wrap up compilation of SUBPROG_DECL, a subprogram body.  */
 
+void
+rest_of_subprog_body_compilation (tree subprog_decl)
+{
   /* We cannot track the location of errors past this point.  */
   error_gnat_node = Empty;
 
@@ -1992,15 +1998,15 @@ end_subprog_body (tree body)
     return;
 
   /* Dump functions before gimplification.  */
-  dump_function (TDI_original, fndecl);
+  dump_function (TDI_original, subprog_decl);
 
   /* ??? This special handling of nested functions is probably obsolete.  */
-  if (!DECL_CONTEXT (fndecl))
-    cgraph_finalize_function (fndecl, false);
+  if (!DECL_CONTEXT (subprog_decl))
+    cgraph_finalize_function (subprog_decl, false);
   else
     /* Register this function with cgraph just far enough to get it
        added to our parent's nested function list.  */
-    (void) cgraph_get_create_node (fndecl);
+    (void) cgraph_get_create_node (subprog_decl);
 }
 
 tree
@@ -2194,6 +2200,20 @@ gnat_types_compatible_p (tree t1, tree t2)
   return 0;
 }
 
+/* Return true if EXPR is a useless type conversion.  */
+
+bool
+gnat_useless_type_conversion (tree expr)
+{
+  if (CONVERT_EXPR_P (expr)
+      || TREE_CODE (expr) == VIEW_CONVERT_EXPR
+      || TREE_CODE (expr) == NON_LVALUE_EXPR)
+    return gnat_types_compatible_p (TREE_TYPE (expr),
+				    TREE_TYPE (TREE_OPERAND (expr, 0)));
+
+  return false;
+}
+
 /* Return true if T, a FUNCTION_TYPE, has the specified list of flags.  */
 
 bool