gimple-low.c (struct lower_data): Add the_return_label and one_return_stmt.

        * gimple-low.c (struct lower_data): Add the_return_label and
        one_return_stmt.
        (lower_function_body): Initialize and use them.
        (lower_return_expr): New.
        (lower_stmt): Call it.
        * gimplify.c (gimplify_return_expr): Force the argument to be either
        null or a result_decl.
        * tree-gimple.c: Update gimple grammer to match.
        * tree-ssa-copyrename.c (copy_rename_partition_coalesce): Deny
        coalescing of result_decls.
testsuite/
        * gcc.dg/tree-ssa/20030728-1.c: Fixup return value to not match
        if temporaries.

From-SVN: r82701