[Bug tree-optimization/87645] [7/8 Regression] gcc hangs up on vr_values::vrp_visit_assignment_or_call

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87645

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Fri Oct 19 14:26:35 2018
New Revision: 265315

URL: https://gcc.gnu.org/viewcvs?rev=265315&root=gcc&view=rev
Log:
2018-10-19  Richard Biener  <rguent...@suse.de>

        PR middle-end/87645
        Backport from mainline
        2018-07-12  Richard Biener  <rguent...@suse.de>

        * tree-ssa-sccvn.c (mprts_hook_cnt): Remove.
        (vn_lookup_simplify_result): Remove recursion limit applied
        here.
        (vn_nary_build_or_lookup_1): Adjust.
        (try_to_simplify): Likewise.
        * gimple-match-head.c (gimple_resimplify1): Instead apply one
        here.
        (gimple_resimplify2): Likewise.
        (gimple_resimplify3): Likewise.
        (gimple_resimplify4): Likewise.

        * gcc.dg/torture/pr87645.c: New testcase.

Added:
    branches/gcc-8-branch/gcc/testsuite/gcc.dg/torture/pr87645.c
Modified:
    branches/gcc-8-branch/gcc/ChangeLog
    branches/gcc-8-branch/gcc/gimple-match-head.c
    branches/gcc-8-branch/gcc/testsuite/ChangeLog
    branches/gcc-8-branch/gcc/tree-ssa-sccvn.c