[Bug tree-optimization/77498] [7 regression] Performance drop after r239414 on spec2000/172mgrid

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77498

--- Comment #15 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Thu Mar 30 07:15:39 2017
New Revision: 246583

URL: https://gcc.gnu.org/viewcvs?rev=246583&root=gcc&view=rev
Log:
2017-03-30  Richard Biener  <rguenther@suse.de>

        PR tree-optimization/77498
        * tree-ssa-pre.c (phi_translate_1): Do not allow simplifications
        to non-constants over backedges.

        * gfortran.dg/pr77498.f: New testcase.

Added:
    trunk/gcc/testsuite/gfortran.dg/pr77498.f
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-pre.c