From: "Joseph S. Myers" <joseph@codesourcery.com>
To: "Shih-Yuan Lee (FourDollars)" <sylee@canonical.com>
Cc: <patches@eglibc.org>, <libc-ports@sourceware.org>,
<rex.tsai@canonical.com>, <jesse.sung@canonical.com>,
<yc.cheng@canonical.com>, Shih-Yuan Lee <fourdollars@gmail.com>
Subject: Re: [PATCH] ARM: NEON detected memcpy.
Date: Wed, 03 Apr 2013 15:08:00 -0000 [thread overview]
Message-ID: <Pine.LNX.4.64.1304031505020.580@digraph.polyomino.org.uk> (raw)
In-Reply-To: <CAAT15mNnqeb6tuVdV6b4uJf-qFDH1acxevyW6f-gH+SkguENmg@mail.gmail.com>
On Wed, 3 Apr 2013, Shih-Yuan Lee (FourDollars) wrote:
> I am working on the NEON detected memcpy.
> This is based on what Siarhei Siamashka did at 2009 [1].
I still don't see any copyright assignment on file (whether individual
with an employer disclaimer, or corporate) that would cover that work.
Without one, we can't use it, and I advise anyone working on NEON memcpy
not to look at it.
I was previously told by people at ARM that NEON memcpy wasn't a good idea
in practice because of raised power consumption, context switch costs etc.
from using NEON in processes that otherwise didn't use it, even if it
appeared superficially beneficial in benchmarks.
--
Joseph S. Myers
joseph@codesourcery.com
next prev parent reply other threads:[~2013-04-03 15:08 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-04-03 7:58 Shih-Yuan Lee (FourDollars)
2013-04-03 8:15 ` Will Newton
2013-04-03 9:19 ` Ondřej Bílka
2013-04-03 15:08 ` Joseph S. Myers [this message]
2013-04-03 15:48 ` Shih-Yuan Lee (FourDollars)
2013-04-03 16:02 ` Joseph S. Myers
2013-04-04 3:56 ` Shih-Yuan Lee (FourDollars)
2013-04-03 16:20 ` [Patches] " Ondřej Bílka
2013-04-04 4:15 ` Shih-Yuan Lee (FourDollars)
2013-04-04 6:37 ` Ondřej Bílka
2013-04-08 9:12 ` Will Newton
2013-04-08 10:27 ` Ondřej Bílka
2013-04-09 8:45 ` Richard Earnshaw
2013-04-09 9:05 ` Richard Earnshaw
2013-04-09 12:04 ` Ondřej Bílka
2013-04-09 12:59 ` Carlos O'Donell
2013-04-09 15:00 ` Richard Earnshaw
2013-04-09 15:54 ` Ondřej Bílka
2013-04-09 15:59 ` Carlos O'Donell
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