linux-kernel - Re: [PATCH 2/4] lib: vsprintf: Optimize division by 10000

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Message-ID: <xa1twqzk640j.fsf@mina86.com>
Date:	Sun, 23 Sep 2012 19:30:20 +0200
From:	Michal Nazarewicz <mpn@...gle.com>
To:	George Spelvin <linux@...izon.com>, vda.linux@...glemail.com
Cc:	hughd@...gle.com, linux-kernel@...r.kernel.org, linux@...izon.com
Subject: Re: [PATCH 2/4] lib: vsprintf: Optimize division by 10000

On Fri, Aug 03 2012, George Spelvin wrote:
> The same multiply-by-inverse technique can be used to
> convert division by 10000 to a 32x32->64-bit multiply.
>
> Signed-off-by: George Spelvin <linux@...izon.com>

You are using a 64-bit multiply in a path that is designed for 32-bit
processors, which makes me feel that it will be slower.

-- 
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.o. | Liege of Serenely Enlightened Majesty of      o' \,=./ `o
..o | Computer Science,  Michał “mina86” Nazarewicz    (o o)
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