From: Richard Earnshaw <rearnsha@arm.com>
To: Bernd Schmidt <bernds@codesourcery.com>
Cc: GCC Patches <gcc-patches@gcc.gnu.org>
Subject: Re: ARM patch: Add a Thumb-1 ldrsb peephole
Date: Fri, 09 Jul 2010 10:24:00 -0000 [thread overview]
Message-ID: <1278671074.19473.6.camel@e102346-lin.cambridge.arm.com> (raw)
In-Reply-To: <4C36F592.6040901@codesourcery.com>
On Fri, 2010-07-09 at 12:10 +0200, Bernd Schmidt wrote:
> Here's a small by-product of my attempts to tune Thumb-1 code.
>
> - add r3, r3, #124
> - mov r7, #0
> + mov r7, #124
> ldrsb r7, [r3, r7]
>
> Tested in the same run as mentioned in
> http://gcc.gnu.org/ml/gcc-patches/2010-07/msg00756.html
>
> Ok?
>
This is OK.
Hmm, makes me think. Could we also have a peephole to optimize the
thumb-2 case?
add r3, r3, r4
ldrsb r7, [r3, #124] // 32-bit, r3 dead
into
add r3, r3, #124
ldrsb r7, [r3, r4] // 16-bit
prev parent reply other threads:[~2010-07-09 10:24 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-07-09 10:11 Bernd Schmidt
2010-07-09 10:24 ` Richard Earnshaw [this message]
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=1278671074.19473.6.camel@e102346-lin.cambridge.arm.com \
--to=rearnsha@arm.com \
--cc=bernds@codesourcery.com \
--cc=gcc-patches@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).