[Bug tree-optimization/83668] [8 Regression] wrong code with -O -fno-tree-dominator-opts -fgraphite-identity

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83668

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Tue Jan  9 13:35:43 2018
New Revision: 256381

URL: https://gcc.gnu.org/viewcvs?rev=256381&root=gcc&view=rev
Log:
2018-01-09  Richard Biener  <rguenther@suse.de>

        PR tree-optimization/83668
        * graphite.c (canonicalize_loop_closed_ssa): Add edge argument,
        move prologue...
        (canonicalize_loop_form): ... here, renamed from ...
        (canonicalize_loop_closed_ssa_form): ... this and amended to
        swap successor edges for loop exit blocks to make us use
        the RPO order we need for initial schedule generation.

        * gcc.dg/graphite/pr83668.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/graphite/pr83668.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/graphite.c
    trunk/gcc/testsuite/ChangeLog