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From: Szabolcs Nagy <nsz@port70.net>
To: musl@lists.openwall.com
Subject: Re: Re: [PATCH] Added ARM optimised memcpy implementation
Date: Fri, 8 Mar 2013 09:24:18 +0100	[thread overview]
Message-ID: <20130308082418.GT6181@port70.net> (raw)
In-Reply-To: <CAPfzE3YiKKhhzW8-_94+yfd6Vn+83OCBnrwSY8hOVc9U-BbjQQ@mail.gmail.com>

* Andre Renaud <andre@bluewatersys.com> [2013-03-08 10:48:47 +1300]:
> Was there any form of consensus over whether it was possible to get
> some version of these ARM optimisations merged?

eventually it will be merged i think, but

we have seen string optimizations go very wrong (glibc sse mess..)
so it should be verified to work properly in cornercases

we did not see much measurement data (x% speedup is not measurement
data, the speedup will depend on alignment and size, i guess small
and aligned memcpy will actually be slower than the current c)

most string functions are compiler builtins, so in some cases the
compiler will know better what to do than libc

and it's extra code to maintain, bugfixes get into musl much easier
than arch specific optimizations

but if there is a strong cause for the change then i dont think
anyone is opposed to it


      reply	other threads:[~2013-03-08  8:24 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-03-01  1:24 Andre Renaud
2013-03-01  1:27 ` Andre Renaud
2013-03-01  3:14   ` nwmcsween
2013-03-01  7:26     ` Szabolcs Nagy
2013-03-02 20:28       ` Andre Renaud
2013-03-07 21:48 ` Andre Renaud
2013-03-08  8:24   ` Szabolcs Nagy [this message]

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