From: Szabolcs Nagy <szabolcs.nagy@arm.com>
To: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
Cc: "naohirot@fujitsu.com" <naohirot@fujitsu.com>,
'GNU C Library' <libc-alpha@sourceware.org>
Subject: Re: [PATCH v2] AArch64: Improve A64FX memcpy
Date: Wed, 1 Dec 2021 10:04:27 +0000 [thread overview]
Message-ID: <20211201100427.GP1982710@arm.com> (raw)
In-Reply-To: <VE1PR08MB55993C0B47DFDB8E27B2F55E83B89@VE1PR08MB5599.eurprd08.prod.outlook.com>
The 10/14/2021 15:53, Wilco Dijkstra via Libc-alpha wrote:
> Hi Naohiro,
>
> This is v2 of the A64FX memcpy - in the end I decided on a complete rewrite.
> Performance is improved by streamlining the code, aligning to vector size in
> large copies and using a single unrolled loop for all sizes. The codesize for
> memcpy and memmove goes down from 1796 bytes to 868 bytes (only 70%
> larger than memcpy_advsimd.S).
>
> Performance is better in all cases: bench-memcpy-random is 2.3% faster overall,
> bench-memcpy-large is 33% faster for large sizes, bench-memcpy-walk is 25%
> faster for small sizes and 20% for the largest sizes. The geomean of all tests in
> bench-memcpy is 5.1% better, and total time is reduced by 4%.
>
> Passes GLIBC regress, OK for commit?
i am waiting for confirmation if this is what we want for a64fx.
prev parent reply other threads:[~2021-12-01 10:04 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-14 15:53 Wilco Dijkstra
2021-12-01 10:04 ` Szabolcs Nagy [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=20211201100427.GP1982710@arm.com \
--to=szabolcs.nagy@arm.com \
--cc=Wilco.Dijkstra@arm.com \
--cc=libc-alpha@sourceware.org \
--cc=naohirot@fujitsu.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).