From: Rich Felker <dalias@libc.org>
To: musl@lists.openwall.com
Subject: Re: [PATCH 1/2] x86_64/memset: simple optimizations
Date: Tue, 10 Feb 2015 15:50:47 -0500 [thread overview]
Message-ID: <20150210205047.GK23507@brightrain.aerifal.cx> (raw)
In-Reply-To: <1423589457-8407-1-git-send-email-vda.linux@googlemail.com>
On Tue, Feb 10, 2015 at 06:30:56PM +0100, Denys Vlasenko wrote:
> "and $0xff,%esi" is a six-byte insn (81 e6 ff 00 00 00), can use
> 4-byte "movzbl %sil,%esi" (40 0f b6 f6) instead.
> [...]
Do you want to go ahead with these patches as-is, or consider some of
the other ideas we discussed off-list like avoiding the 64-bit imul
entirely in the small-n case? If you think that's easy as another
incremental change I'll go ahead with these, but if it's basically
going to be backing out these first changes and replacing them with
something different, I'm not sure if it makes sense to commit one then
the other.
Rich
next prev parent reply other threads:[~2015-02-10 20:50 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-02-10 17:30 Denys Vlasenko
2015-02-10 17:30 ` [PATCH 2/2] x86_64/memset: avoid prforming final store twice Denys Vlasenko
2015-02-10 20:50 ` Rich Felker [this message]
2015-02-10 21:08 ` [PATCH 1/2] x86_64/memset: simple optimizations Denys Vlasenko
2015-02-10 21:37 ` Rich Felker
2015-02-10 22:36 ` Rich Felker
2015-02-10 23:20 ` Rich Felker
2015-02-11 1:07 ` Denys Vlasenko
2015-02-11 1:21 ` Rich Felker
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=20150210205047.GK23507@brightrain.aerifal.cx \
--to=dalias@libc.org \
--cc=musl@lists.openwall.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.
Code repositories for project(s) associated with this public inbox
https://git.vuxu.org/mirror/musl/
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 NNTP newsgroup(s).