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Subject: Re: WCCC: Almost no hardwareadvantage for Crafty

Author: Vincent Diepeveen

Date: 13:04:23 06/29/04

Go up one level in this thread


On June 29, 2004 at 12:52:43, Robert Hyatt wrote:

>On June 29, 2004 at 12:31:00, Vincent Diepeveen wrote:
>
>>On June 29, 2004 at 09:00:51, Ingo Bauer wrote:
>>
>>>On June 29, 2004 at 08:26:15, Zach Wegner wrote:
>>>
>>>>One important point is that crafty uses bitboards, so it will have an additional
>>>>speedup on a 64 bit processor.
>>>
>>>http://www.talkchess.com/forums/1/message.html?372849
>>>
>>>According to yesterdays news its ~47%. Assuming that the hardware is equal and
>>>that double speed gives 60 ELO Crafty wins 30 ELO. We will see soon if this will
>>>be enough.
>>>
>>>Bye Ingo
>>
>>The 32 bits version is using 8 registers.
>>The 64 bits version uses 16 registers.
>>
>>And another few tiny differences.
>>
>>Crafty loses always 1 register to index which thread it is using, so the
>>advantage of going from 8 to 16 is a big one.
>>
>>Then i do not know whether the 64 bits version uses inline assembly versus the
>>32 bits version not using it and the compiler versions and type of compilers
>>used is unclear.
>
>
>If you are going to write about what you don't know, we are going to be here all
>day.
>
>the pointer cost me 3-4% when I added it a few years back.  That is not going to
>be a "big one" when moving to 16 registers.
>
>Both versions use inline assembly for FirstOne() and LastOne() and that's it.
>There is no other assembly in Crafty other than my spinlock code for the SMP
>stuff...
>
>On windows there is no inline asm at all as windows has a built-in intrinsic to
>get to BSF/BSR...

Do you run in windows at the world champs 2004?

This i ask because Eugene's beta compiler won't run under linux i guess...

By the way i thought Eugene was working at the IA64 a while ago, has that team
been moved to x86-64 nowadays and has IA64 development been stopped now?





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