Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Bitboard by any simple engine?

Author: Uri Blass

Date: 02:35:31 05/30/04

Go up one level in this thread


On May 30, 2004 at 04:32:50, Sune Fischer wrote:

>On May 30, 2004 at 04:21:46, Tony Werten wrote:
>
>>On May 29, 2004 at 16:09:22, Sune Fischer wrote:
>>
>>>On May 29, 2004 at 14:41:28, Anthony Cozzie wrote:
>>>
>>>>On May 29, 2004 at 14:26:55, Russell Reagan wrote:
>>>>
>>>>>On May 29, 2004 at 04:24:18, Tony Werten wrote:
>>>>>
>>>>>>Yes, you would have to hop to nextsquare to see how it would go from there. Now
>>>>>>you only have to look what square we are talking about, and if !nil, you will
>>>>>>always know that the nextsquare will be given at *sq++
>>>>>>
>>>>>>So you basicly made "nextsq" and "location of nextsq" independant of each other,
>>>>>>thereby making it independant of board representation and making it more
>>>>>>efficient since you will be traveling through the array in a row, rather than
>>>>>>randomly accesed.
>>>>>
>>>>>Would this be any faster than a traditional array based move generator? As far
>>>>>as I can tell, the array based movegen will iterate over an array, while the
>>>>>move table approach loops over a linked list (effectively). Looping over an
>>>>>array will almost always be at least as fast as looping through a linked list,
>>>>>right? Plus the move table approach uses more memory to accomplish the same
>>>>>thing. You may get some other advantages from a move table approach, but with
>>>>>regard to speed, the move table approach doesn't seem like it would be the
>>>>>fastest.
>>>>
>>>>The magic of Vincent's generator is that there are almost no branches and
>>>>relatively little memory.  The two biggest wastes of time in a modern deeply
>>>>pipelined superscalar processor are branch mispredictions and cache misses.
>>>>
>>>>anthony
>>>
>>>I really don't understand all the hype about a generator.
>>>I just had a look at a profile, mine spends something like 5% generating moves.
>>>That's hardly worth even looking at to optimize.
>>
>>Try doing mobility in eval.
>
>I am doing mobility, but what has that got to do with move generation?
>
>-S.

I do mobility by counting number of legal moves.
move_generation is clearly relevant.

I will probably replace it in the future by better mobility but I plan to
continue using similiar functions.

Uri



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.