[Bug middle-end/57073] __builtin_powif (-1.0, k) should be optimized to "1.0 - 2.0 * (K%2)"

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57073

--- Comment #12 from Tobias Burnus <burnus at gcc dot gnu.org> ---
Author: burnus
Date: Thu May 30 21:32:53 2013
New Revision: 199461

URL: http://gcc.gnu.org/viewcvs?rev=199461&root=gcc&view=rev
Log:
2013-05-30  Tobias Burnus  <bur...@net-b.de>
            Thomas Koenig  <tkoe...@gcc.gnu.org>

        PR middle-end/57073
        * tree-ssa-math-opts.c (execute_cse_sincos): Optimize
        powi (-1.0, k) to (k & 1) ? -1.0 : 1.0.

2013-05-30  Tobias Burnus  <bur...@net-b.de>

        PR middle-end/57073
        * gfortran.dg/power_6.f90: New.


Added:
    trunk/gcc/testsuite/gfortran.dg/power_6.f90
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-math-opts.c