Author: Fabien Letouzey
Date: 06:13:12 03/26/04
Go up one level in this thread
On March 26, 2004 at 09:07:18, Slater Wold wrote: >On March 26, 2004 at 08:50:51, Fabien Letouzey wrote: > >>>>I find it interesting; do you feel like investigating? >>> >>>Yes. I can, and will. I started looking last nite, but ran out of time. >> >>It's not urgent of course, but I think we've got something to learn. >>For instance a way not to do things for 64-bit platforms :) >> >>>>One drawback of 64-bit ints and pointers is that they could take more space in >>>>memory, but I thought I carefully avoided that everywhere ... >> >>>I am not sure what's slowing it down. I could clearly see why it might not get >>>a huge speedup, but the 10% slow down is confusing. >> >>I pass many pointers as function arguments (for instance I pass a pointer to the >>board everyhere instead of using a global variable). To me an argument is the >>same as a local variable, and the slow down is very small on 32-bit platforms I >>am sure. > >This was my first guess. You cannot cast pointers to int, long, ULONG, or DWORD >in 64-bit. And there's a whole slew of other things to look at, also. I don't do any tricks with pointers, I don't even store them in any struct or array (only local variables, that's registers or stack). I just pass them as argument; no pointer arithmetic ... >It very well maybe a part of it, but I think investigating the pointers, >arguments, and variables is a better place to start. Well if profiling reveals a clear difference between the 32-bit and 64-bit version that would be easy. Of course I am expecting no such thing. Alternately, I could read the AMD 64-bit recommendations looking for something that I do differently. I didn't bother because Fruit does not use bitboards. Fabien.
This page took 0.01 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.