From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
	id 25C0A3858D35; Thu, 29 Jun 2023 01:58:29 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 25C0A3858D35
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1688003909;
	bh=E0uVbp88bnbVhtAV2ziJbkLuFeeYXiwA+zI1HG8jy/s=;
	h=From:To:Subject:Date:In-Reply-To:References:From;
	b=inBPBa7mXQmx7+FaLKhqkGQt0Wv6B4S87ZmPma7mYqnISSnROxJ8NT5LAl8L72Lms
	 8TL1kBHE42yYlDL0ke1q4fz8NrH6ZlxHf0lZHkcrbTO0Kh/OVjqiCcLpEFC5WcBQEF
	 tRSVlIC7P7XVoaR9QuuIrhifxXW1E4fu/nptIX7k=
From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/110472] 60% slowdown with fwrapv when using openmp
Date: Thu, 29 Jun 2023 01:58:28 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: middle-end
X-Bugzilla-Version: 10.2.1
X-Bugzilla-Keywords: missed-optimization
X-Bugzilla-Severity: normal
X-Bugzilla-Who: pinskia at gcc dot gnu.org
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: cf_gcctarget
Message-ID: <bug-110472-4-BN9zb1dLXd@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-110472-4@http.gcc.gnu.org/bugzilla/>
References: <bug-110472-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
List-Id: <gcc-bugs.sourceware.org>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110472

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|                            |x86_64-linux-gnu

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I think it is just wrong iv-opt choices.

Works just fine on aarch64-linux-gnu too:
ubuntu@ubuntu:~/src/upstream-gcc-aarch64\# ~/upstream-gcc/bin/gcc t4.c -O2
-fopenmp
ubuntu@ubuntu:~/src/upstream-gcc-aarch64\# ./a.out ;echo
time: 15.191220
ubuntu@ubuntu:~/src/upstream-gcc-aarch64\# ~/upstream-gcc/bin/gcc t4.c -O2
-fopenmp -fwrapv
ubuntu@ubuntu:~/src/upstream-gcc-aarch64\# ./a.out ;echo
time: 18.854280
ubuntu@ubuntu:~/src/upstream-gcc-aarch64\# ./a.out ;echo
time: 16.705876
ubuntu@ubuntu:~/src/upstream-gcc-aarch64\# ~/upstream-gcc/bin/gcc t4.c -O2
-fopenmp
ubuntu@ubuntu:~/src/upstream-gcc-aarch64\# ./a.out ;echo
time: 17.491387
ubuntu@ubuntu:~/src/upstream-gcc-aarch64\# ./a.out ;echo
time: 17.519264=