[Bug rtl-optimization/78546] [6 Regression] wrong code at -O2 and above

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78546

--- Comment #18 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Tue Nov 29 07:48:43 2016
New Revision: 242953

URL: https://gcc.gnu.org/viewcvs?rev=242953&root=gcc&view=rev
Log:
2016-11-29  Richard Biener  <rguenther@suse.de>

        PR middle-end/78546
        * match.pd: Add CST1 - (CST2 - A) -> CST3 + A missing case.

        * gcc.dg/tree-ssa/forwprop-36.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/forwprop-36.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/match.pd
    trunk/gcc/testsuite/ChangeLog