Author: Roy Eassa
Date: 12:32:23 08/28/01
Go up one level in this thread
On August 28, 2001 at 13:22:46, Tom Kerrigan wrote: >On August 28, 2001 at 09:57:30, Robert Hyatt wrote: > >>Suppose I have a hardware engine that is based on Crafty. I need a bitmap of >>the occupied squares, but I want it rotated 90 degrees so that ranks become >>files and files become ranks. I can simply pass the original bitmap thru a >>set of gates that will shuffle the bits as needed and compute the rotation in >>less than one hardware cycle. Pretty easy to visualize that, I hope. But now >>I want to do this in software. How are you going to do this? With 64 ANDS to >>isolate each source bit, 64 shifts to shift them to their pre-assigned >>destination in the rotated bitmap, then 64 ORS to merge them together? While >>my hardware solution took zero time? > >I will not reply to every part of your most recent posts. I've already spent way >too much time writing these posts and can't afford much more. > >This seems to be the crux of the matter--your belief that CB is somehow remotely >similar to DB and the similarity qualifies you to make bad guesses about DB. >This is a joke. Yes, CB was written on a Cray, using special Cray/vector >instructions. But these instructions are still simple, sequential, and EASILY >translated to any other general purpose processor (maybe not with terrific >performance, but it's still easy). CB on a PC is a "port" because it's the exact >same program, just running awkwardly. > >In contrast, DB is NOTHING like CB. There's no stream of simple, sequential >instructions at all. I don't know how you would even begin to pretend to "port" >DB to a PC, especially using the chip blueprints as you descriped in your other >post. For example, the DB chip has a pipeline. How do you want to implement that >in software? Run a thread for each stage and needlessly duplicate huge amounts >of information between the threads to simulate latching the pipeline registers? >Do you want to "port" or "emulate" the cascaded adders by doing all sorts of >unnecessary, intermediate addition? The idea is stupid, stupid, stupid. That >anyone would think of it makes me queasy. Or that anyone would think that this >is in some way similar to porting software from general-purpose CPU A to >general-purpose CPU B. > >I don't see what your problem is with simply reimplementing DB's evaluation >terms. It's not hard. They do king attack stuff? I've written code to find all >the attacks to/near the kings in half an hour. I'm absolutely certain I can >implement what you're doing for potentially open files in half an hour, too. >I've spent a lot of time coding up eval terms from different sources (GNU Chess, >HIARCS, etc.) and none of them have ever given me any real programming trouble. >I'm not sure what your hangup is with DB's terms. > >It's convienent that Netscape cut out on you right when you were about to reply >to my 5,000 nodes question. According to the estimates you're standing by, a DB >node would take as long as 5,000 "normal" PC program nodes. Do you honestly >believe that their evaluation is _five thousand_ times more sophisticated than, >say, Crafty's? Because I sure don't. I might accept "twice as sophisticated as >MChess's" or something reasonable, but what you're saying is simply absurd. > >So, that was the last word in this conversation, unless you feel the need to go >back on your word and continue it, which you usually do. > >-Tom I used to naively believe that highly intelligent people could disagree on a technical topic without becoming nasty. Sigh.
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.