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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/57071] Optimize  (-1)**k  to 1 - 2 * mod(K, 2)
Date: Fri, 26 Apr 2013 09:16:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57071

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> 2013-04-26 09:16:41 UTC ---
Note that for the (-1.0)**k case __builtin_powif (-1.0e+0, k) should be
perfectly fine for the middle-end.  _gfortran_pow_i4_i4 (-1, k) is of
course unfortunate and should be optimized by the frontend.