[Bug tree-optimization/86816] [8/9 Regression] ICE: SIGSEGV in tree-ssa-pre / tail_merge_optimize

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86816

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Thu Aug  2 13:19:50 2018
New Revision: 263257

URL: https://gcc.gnu.org/viewcvs?rev=263257&root=gcc&view=rev
Log:
2018-08-02  Richard Biener  <rguent...@suse.de>

        PR tree-optimization/86816
        * tree-ssa-tail-merge.c (tail_merge_valueize): New function
        which checks for value availability before querying it.
        (gvn_uses_equal): Use it.
        (same_succ_hash): Likewise.
        (gimple_equal_p): Likewise.

        * g++.dg/torture/pr86816.C: New testcase.

Added:
    trunk/gcc/testsuite/g++.dg/torture/pr86816.C
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-tail-merge.c