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Date: Thu, 26 Jan 2006 09:30:14 -0800
From: Richard Henderson <rth@twiddle.net>
To: Edgar Toernig <froese@gmx.de>
Cc: Akinobu Mita <mita@miraclelinux.com>, linux-kernel@vger.kernel.org,
       Ivan Kokshaysky <ink@jurassic.park.msu.ru>, Ian Molton <spyro@f2s.com>,
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       ultralinux@vger.kernel.org, Miles Bader <uclinux-v850@lsi.nec.co.jp>,
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Subject: Re: [PATCH 3/6] C-language equivalents of include/asm-*/bitops.h
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References: <20060125112625.GA18584@miraclelinux.com> <20060125113206.GD18584@miraclelinux.com> <20060125200250.GA26443@flint.arm.linux.org.uk> <20060126000618.GA5592@twiddle.net> <20060126053412.0da7f505.froese@gmx.de>
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On Thu, Jan 26, 2006 at 05:34:12AM +0100, Edgar Toernig wrote:
> Why shift at all?

Becuase that *is* a valid architecture tuning knob.  Most risc
machines can't AND with arbitrary constants like that, and loading
the constant might bulk things up more than just using the shift.


r~