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Subject: Re: MSVC .NET 2003 optimization bug [O.T]

Author: Russell Reagan

Date: 16:44:10 04/09/04

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On April 09, 2004 at 19:32:54, Brian Kostick wrote:

>On April 09, 2004 at 18:04:10, Russell Reagan wrote:
>
>>for (row = 11; row < 12; row--)
>>
>>The problem is the comparison: row < 12
>
>
>Looks like nasty code to me. row will soon go negative and stay there for quite
>some time. Maybe I'm not thinking clearly? BK

row is unsigned :) So yes, it is nasty code, because it is not immediately
obvious what is happening, and I'm relying on the unsigned wrap around (for
example: row = 0; row--; now row == 4294967295). If I was writing this for
something that I planned on using I wouldn't have written it that way.

I was just hacking something together this afternoon to output a 12x12 amazons
board (10x10 with padding all the way around). I am writing amazons programs to
benchmark various implementations of various programming languages, so I didn't
care if it was readable, only how fast it ran.

Writing an amazons program is WAY easier than writing a chess program (in my
experience anyway), but it should give us some idea of how a chess program would
perform speed-wise under a particular implementation of a programming language,
since it is similar to chess.



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