From: Agner Fog <agner@agner.org>
To: Basile STARYNKEVITCH <basile@starynkevitch.net>
Cc: gcc@gcc.gnu.org, TimothyPrince@sbcglobal.net
Subject: Re: gcc will become the best optimizing x86 compiler
Date: Thu, 24 Jul 2008 13:59:00 -0000 [thread overview]
Message-ID: <48888388.7060106@agner.org> (raw)
In-Reply-To: <48885927.40908@starynkevitch.net>
Basile STARYNKEVITCH wrote:
>At last, at the recent (july 2008) GCC summit, someone (sorry I forgot
who, probably someone from SuSE)
> proposed in a BOFS to have architecture and machine specific
hand-tuned (or even hand-written assembly) low
> level libraries for such basic things as memset etc..
That's exactly what I meant. The most important memory, string and math
functions should use hand-tuned assembly with CPU dispatching for the
latest instruction sets. My experiments show that the speed can be
improved by a factor 3 - 10 for unaligned memcpy on Intel processors
(http://www.agner.org/optimize/optimizing_cpp.pdf page 12).
There will be more hand-tuning work to do when the 256-bit YMM registes
become available in a few years - and more to gain in speed.
next prev parent reply other threads:[~2008-07-24 13:31 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-07-23 14:59 Is cross-section inlining valid behaviour? Bingfeng Mei
2008-07-23 15:07 ` Richard Guenther
2008-07-23 15:14 ` Dave Korn
2008-07-23 15:31 ` Bingfeng Mei
2008-07-23 17:25 ` gcc will become the best optimizing x86 compiler Agner Fog
2008-07-23 17:33 ` Tim Prince
2008-07-24 8:04 ` Dennis Clarke
2008-07-24 9:41 ` Agner Fog
2008-07-24 10:10 ` Dave Korn
2008-07-24 13:20 ` Basile STARYNKEVITCH
2008-07-24 13:31 ` Dave Korn
2008-07-24 13:59 ` Agner Fog [this message]
2008-07-24 14:40 ` Richard Guenther
2008-07-28 10:57 ` Andrew Haley
2008-07-24 15:02 ` Joseph S. Myers
2008-07-24 16:26 ` Agner Fog
2008-07-24 17:17 ` Basile STARYNKEVITCH
2008-07-24 17:21 ` Raksit Ashok
2008-07-25 7:23 ` Agner Fog
2008-07-26 0:23 ` Michael Meissner
2008-07-26 17:49 ` Agner Fog
2008-07-28 11:45 ` Agner Fog
2008-07-28 14:40 ` Daniel Jacobowitz
2008-07-28 17:37 ` Dennis Clarke
2008-07-28 17:54 ` Paolo Carlini
2008-07-28 18:31 ` Dennis Clarke
2008-07-28 18:37 ` Ian Lance Taylor
2008-07-28 19:44 ` Dave Korn
2008-07-28 21:40 ` Dennis Clarke
2008-07-29 1:31 ` Gerald Pfeifer
2008-07-29 6:29 ` Agner Fog
2008-07-29 9:24 ` Ben Elliston
2008-07-31 8:12 ` Christopher Faylor
2008-07-28 17:19 ` Michael Matz
2008-07-29 6:15 ` Agner Fog
2008-07-29 9:31 ` Richard Guenther
2008-07-29 9:55 ` Steven Bosscher
2008-07-29 13:09 ` Joseph S. Myers
2008-07-29 14:11 ` Michael Matz
2008-07-29 14:45 ` Tim Prince
2008-07-30 16:37 ` Denys Vlasenko
2008-07-30 16:40 ` Denys Vlasenko
2008-07-30 17:52 ` Agner Fog
2008-07-30 22:42 ` Dennis Clarke
2008-07-31 2:57 ` Denys Vlasenko
2008-07-31 8:18 ` Agner Fog
2008-07-31 11:00 ` Dave Korn
2008-07-24 10:09 ` Zoltán Kócsi
2008-07-30 15:34 Eus
2008-07-30 16:09 ` Dennis Clarke
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=48888388.7060106@agner.org \
--to=agner@agner.org \
--cc=TimothyPrince@sbcglobal.net \
--cc=basile@starynkevitch.net \
--cc=gcc@gcc.gnu.org \
/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).