2007-09-07  Richard Guenther  <rguenther@suse.de>

        PR tree-optimization/32586
        * tree-ssa-sccvn.c (simplify_binary_expression): Avoid
        folding if nothing changed.
        (simplify_unary_expression): New function.  Do tree combining
        on conversion like codes.
        (try_to_simplify): Call it.

        * g++.dg/tree-ssa/pr27090.C: Remove XFAILs.
        * gcc.dg/tree-ssa/ssa-fre-1.c: Likewise.
        * gcc.dg/tree-ssa/ssa-fre-3.c: Likewise.
        * gcc.dg/tree-ssa/ssa-fre-5.c: Likewise.
        * gcc.dg/tree-ssa/ssa-fre-4.c: Likewise, remove scan for
        now obsolete simplification.

From-SVN: r128251