From: Steven Bosscher <stevenb.gcc@gmail.com>
To: Andi Kleen <andi@firstfloor.org>
Cc: Richard Guenther <richard.guenther@gmail.com>,
Bernd Schmidt <bernds@codesourcery.com>,
GCC Patches <gcc-patches@gcc.gnu.org>
Subject: Re: Combine four insns
Date: Tue, 10 Aug 2010 16:47:00 -0000 [thread overview]
Message-ID: <AANLkTi=MeRRfBBYcdkdfSrstfLRTH0_NLnujHRBQyz_x@mail.gmail.com> (raw)
In-Reply-To: <8739um8mz5.fsf@basil.nowhere.org>
On Tue, Aug 10, 2010 at 6:13 PM, Andi Kleen <andi@firstfloor.org> wrote:
> Steven Bosscher <stevenb.gcc@gmail.com> writes:
>
>> On Tue, Aug 10, 2010 at 4:39 PM, Richard Guenther
>> <richard.guenther@gmail.com> wrote:
>>> You could enable the heuristic with optimize < 3 && !optimize_size
>>> (thus keep combining everything at -O3 and -Os).
>>
>> Better s/optimize_size/optimize_bb_for_size(BLOCK_FOR_INSN (i0))/
>
> That would mean that a -O2 build where all BBs are cold for some
> reason would be 1% slower, right?
It's not 1% anymore with the heuristic to only do leaves with 4 insns.
Before that (from Bernd's numbers):
$ grep Trying.four log |wc -l
307743
and after:
$ grep Trying.four log2 |wc -l
187120
So only ~60% of the attempts and probably also less time simplifying.
Slowdown should be less than 0.5% after that.
> To be honest I didn't fully understand why it's ok for -Os
> to be 1% slower. A lot of people use -Os.
Yes, and they expect the smallest code possible. This patch does seem
to help for that.
Ciao!
Steven
next prev parent reply other threads:[~2010-08-10 16:38 UTC|newest]
Thread overview: 129+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-08-06 14:49 Bernd Schmidt
2010-08-06 15:04 ` Richard Guenther
2010-08-06 20:08 ` Bernd Schmidt
2010-08-06 20:37 ` Richard Guenther
2010-08-06 21:53 ` Jeff Law
2010-08-06 22:41 ` Bernd Schmidt
2010-08-06 23:47 ` Richard Guenther
2010-08-07 8:11 ` Eric Botcazou
2010-08-09 12:29 ` Bernd Schmidt
2010-08-09 12:39 ` Steven Bosscher
2010-08-09 13:48 ` Bernd Schmidt
2010-08-10 2:51 ` Laurynas Biveinis
2010-08-09 12:41 ` Michael Matz
2010-08-09 14:34 ` Bernd Schmidt
2010-08-09 14:39 ` Toon Moene
2010-08-09 14:50 ` Steven Bosscher
2010-08-09 14:58 ` The speed of the compiler, was: " Toon Moene
2010-08-09 15:00 ` Paul Koning
2010-08-09 15:33 ` Diego Novillo
2010-08-09 15:53 ` Mark Mitchell
2010-08-09 17:15 ` Toon Moene
2010-08-09 17:19 ` Diego Novillo
2010-08-09 17:29 ` Toon Moene
2010-08-09 23:24 ` Chris Lattner
2010-08-10 13:02 ` Toon Moene
2010-08-10 15:36 ` Chris Lattner
2010-08-10 14:58 ` Andi Kleen
2010-08-10 15:03 ` Richard Guenther
2010-08-10 15:32 ` Andi Kleen
2010-08-10 20:09 ` Tom Tromey
2010-08-10 20:23 ` Andi Kleen
2010-08-10 22:40 ` Mike Stump
2010-08-10 23:16 ` Tom Tromey
2010-08-12 21:09 ` Nathan Froyd
2010-08-17 15:14 ` Mark Mitchell
2010-08-10 20:15 ` H.J. Lu
2010-08-12 21:38 ` Vectorized _cpp_clean_line Richard Henderson
2010-08-12 22:18 ` Andi Kleen
2010-08-12 22:32 ` Richard Henderson
2010-08-12 23:10 ` Richard Henderson
2010-08-12 23:13 ` Richard Henderson
2010-08-13 8:33 ` Andi Kleen
2010-08-13 7:26 ` Andi Kleen
2010-08-14 17:14 ` [CFT, v4] " Richard Henderson
2010-08-17 16:59 ` Steve Ellcey
2010-08-17 17:21 ` Richard Henderson
2010-08-17 20:32 ` Steve Ellcey
2010-08-18 17:14 ` Steve Ellcey
2010-08-17 17:32 ` Jakub Jelinek
2010-08-18 3:23 ` Tom Tromey
[not found] ` <1281998097.3725.3.camel@gargoyle>
[not found] ` <4C69C317.2080207@redhat.com>
[not found] ` <1282142212.3725.6.camel@gargoyle>
[not found] ` <4C6BF5F7.7040100@redhat.com>
[not found] ` <1282149264.3725.15.camel@gargoyle>
[not found] ` <4C6C0D92.7080100@redhat.com>
[not found] ` <1282151361.3725.19.camel@gargoyle>
[not found] ` <4C6C166A.90306@redhat.com>
[not found] ` <1282152938.3725.27.camel@gargoyle>
[not found] ` <4C6C39DB.8070409@redhat.com>
2010-08-18 21:50 ` Richard Henderson
2010-08-19 14:12 ` Luis Machado
2010-08-09 17:27 ` The speed of the compiler, was: Re: Combine four insns Joseph S. Myers
2010-08-09 18:23 ` Diego Novillo
2010-08-10 6:20 ` Chiheng Xu
2010-08-10 7:22 ` Chiheng Xu
2010-08-09 17:34 ` Steven Bosscher
2010-08-09 17:36 ` Diego Novillo
2010-08-09 23:13 ` Cary Coutant
2010-08-09 18:59 ` The speed of the compiler Ralf Wildenhues
2010-08-09 19:04 ` Diego Novillo
2010-08-09 21:12 ` The speed of the compiler, was: Re: Combine four insns Mike Stump
2010-08-09 23:48 ` Cary Coutant
2010-08-10 14:37 ` Bernd Schmidt
2010-08-10 14:40 ` Richard Guenther
2010-08-10 14:49 ` Bernd Schmidt
2010-08-10 15:06 ` Steven Bosscher
2010-08-10 15:06 ` Steven Bosscher
2010-08-10 16:27 ` Andi Kleen
2010-08-10 16:47 ` Steven Bosscher [this message]
2010-08-10 16:55 ` Andi Kleen
2010-08-10 17:03 ` David Daney
2010-08-11 8:53 ` Richard Guenther
2010-08-16 20:42 ` Mark Mitchell
2010-08-16 20:45 ` Bernd Schmidt
2010-08-16 21:03 ` Mark Mitchell
2010-08-18 20:50 ` Eric Botcazou
2010-08-18 22:03 ` Bernd Schmidt
2010-08-19 8:04 ` Eric Botcazou
2010-08-19 15:44 ` Mark Mitchell
2010-08-19 18:13 ` Bernd Schmidt
2010-08-19 18:25 ` Mark Mitchell
2010-08-19 18:42 ` Richard Henderson
2010-08-19 22:14 ` Eric Botcazou
2010-08-19 22:19 ` Bernd Schmidt
2010-08-19 22:21 ` Eric Botcazou
2010-08-19 22:37 ` Bernd Schmidt
2010-08-19 22:53 ` Steven Bosscher
2010-08-19 23:34 ` Andrew Pinski
2010-08-19 23:40 ` Bernd Schmidt
2010-08-20 1:59 ` Mark Mitchell
2010-08-20 3:56 ` Diego Novillo
2010-08-20 4:13 ` Mark Mitchell
2010-08-20 14:14 ` Eric Botcazou
2010-08-20 14:36 ` Paolo Bonzini
2010-08-21 13:46 ` Eric Botcazou
2010-08-23 17:03 ` Richard Guenther
2010-08-23 17:08 ` Mark Mitchell
2010-08-20 14:44 ` Mark Mitchell
2010-08-20 10:21 ` Paolo Bonzini
2010-08-20 0:21 ` H.J. Lu
2010-08-20 0:36 ` Bernd Schmidt
2010-08-20 14:07 ` H.J. Lu
2010-08-11 12:32 ` Michael Matz
2010-08-06 15:08 ` Steven Bosscher
2010-08-06 16:45 ` Paolo Bonzini
2010-08-06 17:22 ` Steven Bosscher
2010-08-06 18:02 ` Jeff Law
2010-08-06 20:44 ` Steven Bosscher
2010-08-06 20:48 ` Richard Guenther
2010-08-06 21:49 ` Jeff Law
2010-08-06 18:56 ` Vladimir N. Makarov
2010-08-06 19:02 ` Steven Bosscher
2010-08-06 21:11 ` Chris Lattner
2010-08-08 11:40 ` Paolo Bonzini
2010-08-12 5:53 ` Ian Lance Taylor
2010-08-06 19:20 ` Bernd Schmidt
2010-08-06 19:37 ` Jeff Law
2010-08-06 19:43 ` Bernd Schmidt
2010-08-06 21:46 ` Jeff Law
2010-08-09 14:54 ` Mark Mitchell
2010-08-09 15:04 ` Bernd Schmidt
2010-08-09 16:02 ` Chris Lattner
2010-08-09 16:07 ` Richard Guenther
2010-08-09 17:28 ` Joseph S. Myers
2010-08-09 16:19 ` Mark Mitchell
2010-08-09 17:02 ` Chris Lattner
2010-08-10 2:50 ` Mark Mitchell
2010-08-10 15:35 ` Chris Lattner
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='AANLkTi=MeRRfBBYcdkdfSrstfLRTH0_NLnujHRBQyz_x@mail.gmail.com' \
--to=stevenb.gcc@gmail.com \
--cc=andi@firstfloor.org \
--cc=bernds@codesourcery.com \
--cc=gcc-patches@gcc.gnu.org \
--cc=richard.guenther@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).