[Bug tree-optimization/79088] [7 Regression] wrong code at -O2 on x86_64-linux-gnu

[law at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79088

--- Comment #6 from Jeffrey A. Law <law at gcc dot gnu.org> ---
Author: law
Date: Mon Jan 23 22:29:17 2017
New Revision: 244837

URL: https://gcc.gnu.org/viewcvs?rev=244837&root=gcc&view=rev
Log:
2017-01-23  Richard Biener  <rguenther@suse.de>

        PR tree-optimization/79088
        PR tree-optimization/79188
        * tree-ssa-threadupdate.c (mark_threaded_blocks): Move code
        resetting loop bounds after last path deletion.  Reset loop
        bounds of the target loop, make code match the comments.
        * tree-ssa-threadbackwards.c (pass_early_thread_jumps::execute):
        Make sure loops need no fixups.

        * gcc.dg/torture/pr79088.c: New testcase.
        * gcc.dg/torture/pr79188.c: Likewise.

Added:
    trunk/gcc/testsuite/gcc.dg/torture/pr79088.c
    trunk/gcc/testsuite/gcc.dg/torture/pr79188.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-threadbackward.c
    trunk/gcc/tree-ssa-threadupdate.c