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Date: Thu, 21 Dec 2000 10:28:09 +0000 (GMT)
From: Bernd Schmidt <bernds@redhat.com>
To: Matthias Andree <matthias.andree@stud.uni-dortmund.de>
Cc: Steve Grubb <ddata@gate.net>,
        Linux-Kernel mailing list <linux-kernel@vger.kernel.org>
Subject: Re: [Patch] performance enhancement for simple_strtoul
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On Thu, 21 Dec 2000, Matthias Andree wrote:
>
> x * 10 can be written as:
>
> (x << 2 + x) << 1   = (4x+x) * 2
> (x << 3) + (x << 1) = 8x + 2x

Or as "x * 10".  Which has the advantage of actually being readable, and
letting the compiler optimize it into one of the other forms if that's
profitable on the machine you are compiling for.

Why do you guys bother making strtoul run fast anyway?  Surely it's not on
any critical path in the kernel?


Bernd

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