linux-kernel - Re: [PATCH] staging: s5k3e2fx.c: reduce complexity by factoring

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Date:	Mon, 14 Dec 2009 20:02:47 -0800
From:	Ray Lee <ray-lk@...rabbit.org>
To:	Justin Madru <jdm64@...ab.com>
Cc:	gregkh@...e.de, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] staging: s5k3e2fx.c: reduce complexity by factoring

On Sat, Dec 5, 2009 at 6:03 PM, Justin Madru <jdm64@...ab.com> wrote:
> I was style fixing some code when I ran into this code.
> It seems like the code could be reduced, by factoring the expression.
> But this results in a very simple expression.
>
> Am I assuming something wrong? Or is this a bug in the original code?
> This doesn't look right because the assignment of s_move[i] has no mention
> of the loop counter.

Algebraic factoring is not valid in general when dealing with pure
integer expressions that may contain rounding issues. I haven't
checked to see if that's the case with the code you're changing, but
that sort of expression you're removing is very commonly used exactly
to deal with rounding issues.
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