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From: John Baldwin <jhb@freebsd.org>
To: freebsd-current@freebsd.org
Subject: Re: SSE in libthr
Date: Mon, 06 Apr 2015 15:56:35 -0400
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 (bigwig.baldwin.cx); Mon, 06 Apr 2015 16:18:26 -0400 (EDT)
Cc: Adrian Chadd <adrian@freebsd.org>, David Chisnall <theraven@freebsd.org>
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On Saturday, March 28, 2015 10:41:48 AM Adrian Chadd wrote:
> Ok, so how do we reduce the amount of FPU save and restores, or make
> them cheaper?

Or make them more useful.  If you are using SSE/AVX more often between context
switches in ways that are beneficial then that might offset the cost of the
save and restore and result in a net win.  I have variants of strlen, memcpy,
and memset that use SSE.  However, microbenchmarks aren't super useful as you
have noted.  If you would like to try these out in some real workloads I can
provide a patch to libc.

-- 
John Baldwin