2004-04-29  Paolo Bonzini  <bonzini@gnu.org>

        * combine.c (combine_simplify_rtx): Adjust call to use
        simplify_relational_operation.  Do not use SELECT_CC_MODE
        when a comparison already has a MODE_CC mode.
        (simplify_set): simplify_relational_operation may now
        return another relational expression.
        * cse.c (fold_rtx): simplify_relational_operation now
        takes of computing the comparison mode.
        * dojump.c (compare_from_rtx): Use simplify_relational_operation,
        remove dead code.
        (do_compare_rtx_and_jump): Likewise.
        * integrate.c (subst_constants): simplify_relational_operation
        may now return another relational expression.
        * simplify-rtx.c (simplify_gen_relational): Move most code to
        the new simplify_relational_operation and
        simplify_relational_operation_1 functions.
        (simplify_relational_operation): Rewritten.
        (simplify_relational_operation_1): New function.
        (simplify_ternary_operation): simplify_relational_operation
        may now return another relational expression.
        (simplify_rtx): Remove unnecessary temp variable.

From-SVN: r81282