From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Stephen R. van den Berg" <srb@cuci.nl>
Subject: Re: [PATCH] speed: reuse char instead of recreation in loop
Date: Tue, 26 May 2009 13:54:03 +0200
Message-ID: <20090526115403.GA4246@cuci.nl>
References: <pan.2009.05.25.19.44.10@fedoraproject.org> <20090525201602.GA18471@atjola.homenet> <pan.2009.05.25.20.40.20@fedoraproject.org> <alpine.LNX.2.00.0905251733240.2147@iabervon.org>
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Cc: Thomas Spura <tomspur@fedoraproject.org>, git@vger.kernel.org
To: Daniel Barkalow <barkalow@iabervon.org>
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Daniel Barkalow wrote:
>On Mon, 25 May 2009, Thomas Spura wrote:
>> Am Mon, 25 May 2009 22:16:02 +0200 schrieb Bj?rn Steinbrink:
>> > On 2009.05.25 19:44:10 +0000, Thomas Spura wrote:
>> >> Move a char and a char * outside of a for loop for speed improvements

>> > I doubt that this makes any difference at all.

>> With ints, the loop costs about 40% of speed. Without recreation, it 
>> should be always faster.

>optimizations in this code for it to make, but, in general, letting 
>variables in loops go out of scope (in C) only improves optimization 
>possibilities.

Quite.  The proposed patch is more likely to slow down the code than to
speed it up.
-- 
Sincerely,
           Stephen R. van den Berg.

E Pluribus Unix.