This is the mail archive of the
gcc-bugs@gcc.gnu.org
mailing list for the GCC project.
[Bug tree-optimization/83326] [8 Regression] SPEC CPU2017 648.exchange2_s ~6% performance regression with r255267 (reproducer attached)
- From: "rguenth at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: Thu, 14 Dec 2017 14:32:56 +0000
- Subject: [Bug tree-optimization/83326] [8 Regression] SPEC CPU2017 648.exchange2_s ~6% performance regression with r255267 (reproducer attached)
- Auto-submitted: auto-generated
- References: <bug-83326-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83326
--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Thu Dec 14 14:32:24 2017
New Revision: 255635
URL: https://gcc.gnu.org/viewcvs?rev=255635&root=gcc&view=rev
Log:
2017-12-14 Richard Biener <rguenther@suse.de>
PR tree-optimization/83326
* tree-ssa-loop-ivcanon.c (try_unroll_loop_completely): Add
may_be_zero parameter and handle it by not marking the first
peeled copy as not exiting the loop.
(try_peel_loop): Likewise.
(canonicalize_loop_induction_variables): Use number_of_iterations_exit
to handle the case of constant or zero iterations and perform
loop header copying on-the-fly.
* gcc.dg/tree-ssa/pr81388-2.c: Adjust.
Modified:
trunk/gcc/ChangeLog
trunk/gcc/testsuite/ChangeLog
trunk/gcc/testsuite/gcc.dg/tree-ssa/pr81388-2.c
trunk/gcc/tree-ssa-loop-ivcanon.c