Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: 0x88 and move generator speed

Author: Severi Salminen

Date: 03:59:03 02/02/01

Go up one level in this thread


>But i don't see the speedup when compared to crafty when
>talking about branches here. You use on average 2 JZ instructions
>for each move. Let's do a very non-educated guess and estimate
>that from each 2 JZ instructions at least 1 is mispredicted.
>
>That means that you lose in number of clocks (at least) on the
>  P3 : 10
>  P4 : 20
>
>So you waste 10 CLOCKS on a P3!!!!!!!
>Just to get a single instruction out of a bitboard!
>Added to that is a lot of extra overhead also, as you use
>a lot of complex instructions. psllq i need to figure out what
>it does but perhaps you can already post that!.

Could you give me a basic rule of thumb for this branching stuff. The less we
have jumps the faster we are? And what about when processor predicts right the
destination?

Severi



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.