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To: "Matthew Fleming" <matthew.fleming@isilon.com>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Tue, 25 May 2010 09:34:48 MST."
	<06D5F9F6F655AD4C92E28B662F7F853E021D4D9D@seaxch09.desktop.isilon.com> 
Date: Tue, 25 May 2010 16:37:12 +0000
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Cc: freebsd-arch@freebsd.org
Subject: Re: crc32 table 
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In message <06D5F9F6F655AD4C92E28B662F7F853E021D4D9D@seaxch09.desktop.isilon.co
m>, "Matthew Fleming" writes:

>Is there an interest in another crc32 implementation for the kernel =
>which uses this polynomial and uses the SSE 4.2 instruction when =
>available?  (This support would require kib's FPU patch).

It would be a better idea to add a kernel facility to build a
CRC table to a given polynomial.  The code to do this is very
compact and would take up less space than N CRC tables which are
likely not used in most running kernels.

Poul-Henning

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.