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Date: Fri, 1 Mar 2013 02:46:41 +0000
From: Alexey Dokuchaev <danfe@FreeBSD.org>
To: Alexander Motin <mav@FreeBSD.org>
Subject: Re: svn commit: r247460 - head/sys/dev/acpica
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Cc: Davide Italiano <davide@FreeBSD.org>, svn-src-head@freebsd.org,
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On Thu, Feb 28, 2013 at 07:37:32PM +0200, Alexander Motin wrote:
> SBT_1US is 4294 (0x10c6). The best that compiler may do is replace
> division with multiplication. In fact, Clang even does this on amd64.
> But on i386 it calls __divdi3(), doing 64bit division in software. Shift
> is definitely cheaper and 5% precision is fine here.

I see, thanks for explanation.  I overlooked SBT_1US definition.

./danfe