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From: "ubizjak at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/56309] -O3 optimizer generates conditional moves instead of compare and branch resulting in almost 2x slower code
Date: Thu, 14 Feb 2013 17:34:00 -0000	[thread overview]
Message-ID: <bug-56309-4-F41iwU38fw@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-56309-4@http.gcc.gnu.org/bugzilla/>


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56309

--- Comment #15 from Uros Bizjak <ubizjak at gmail dot com> 2013-02-14 17:34:15 UTC ---
(In reply to comment #13)
> $ g++ --version
> g++ (GCC) 4.7.2 ...
> $ g++ -O3 -std=c++11 by-val-O3.ii ; ./a.out
> Took 14.31 seconds total.
> $ g++ -O3 -std=c++11 by-val-O3.ii -fvect-cost-model ; ./a.out
> Took 14.31 seconds total.
> $ g++ -O3 -std=c++11 by-val-O3.ii -fno-tree-vectorize ; ./a.out
> Took 10.25 seconds total.

This is red herring, see PR53346c11:

--q--
You are right. -ftree-vectorize implies -ftree-loop-if-convert and this option
makes all the difference!
--/q--

Please try wiht -ftree-vectorize -fno-tree-loop-if-convert.


  parent reply	other threads:[~2013-02-14 17:34 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-02-13 20:21 [Bug middle-end/56309] New: " arturomdn at gmail dot com
2013-02-13 20:23 ` [Bug middle-end/56309] " arturomdn at gmail dot com
2013-02-13 20:26 ` [Bug target/56309] " pinskia at gcc dot gnu.org
2013-02-13 20:29 ` arturomdn at gmail dot com
2013-02-14  8:16 ` ubizjak at gmail dot com
2013-02-14  8:22 ` ubizjak at gmail dot com
2013-02-14  8:28 ` ubizjak at gmail dot com
2013-02-14 14:49 ` ysrumyan at gmail dot com
2013-02-14 15:53 ` arturomdn at gmail dot com
2013-02-14 16:01 ` arturomdn at gmail dot com
2013-02-14 16:44 ` arturomdn at gmail dot com
2013-02-14 16:59 ` steven at gcc dot gnu.org
2013-02-14 17:10 ` steven at gcc dot gnu.org
2013-02-14 17:26 ` [Bug tree-optimization/56309] " steven at gcc dot gnu.org
2013-02-14 17:31 ` arturomdn at gmail dot com
2013-02-14 17:34 ` ubizjak at gmail dot com [this message]
2013-02-14 17:43 ` arturomdn at gmail dot com
2013-02-14 17:50 ` ubizjak at gmail dot com
2013-02-14 18:23 ` ubizjak at gmail dot com
2013-02-14 18:35 ` [Bug target/56309] " ubizjak at gmail dot com
2013-02-14 22:18 ` steven at gcc dot gnu.org
2013-02-15  6:50 ` izamyatin at gmail dot com
2013-02-15  7:15 ` jakub at gcc dot gnu.org
2013-02-15  9:33 ` rguenth at gcc dot gnu.org
2013-02-15  9:36 ` rguenth at gcc dot gnu.org
2013-02-17  8:35 ` [Bug target/56309] conditional moves instead of compare and branch result " ubizjak at gmail dot com
2013-02-17  8:38 ` ubizjak at gmail dot com
2013-02-17 10:10 ` ubizjak at gmail dot com
2013-09-22  6:37 ` icegood1980 at gmail dot com
2013-10-18  9:12 ` jakub at gcc dot gnu.org
2013-10-18 10:06 ` ubizjak at gmail dot com
2015-08-06  9:35 ` ysrumyan at gmail dot com
2021-09-04 20:24 ` peter at cordes dot ca
2021-09-04 20:26 ` peter at cordes dot ca

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