In article <[EMAIL PROTECTED]>, Mike Meyer <[EMAIL PROTECTED]> wrote:
> "Harald Armin Massa" <[EMAIL PROTECTED]> writes: > >>Faster than assembly? LOL... :) > > why not? Of course, a simple script like "copy 200 bytes from left to > > right" can be handoptimized in assembler and run at optimum speed. > > Maybe there is even a special processor command to do that. > > Chances are, version 1 of the system doesn't have the command. Version > 2 does, but it's no better than the obvious hand-coded loop. Version 3 > finally makes it faster than the hand-coded loop, if you assume you > have the instruction. If you have to test to see if you can use it, > the hand-coded version is equally fast. Version 4 makes it faster even > if you do the test, so you want to use it if you can. Of course, by > then there'll be a *different* command that can do the same thing,j and > is faster in some conditions. > > Dealing with this in assembler is a PITA. If you're generating code on > the fly, you generate the correct version for the CPU you're running > on, and that's that. It'll run at least as fast as hand-coded > assembler on every CPU, and faster on some. Actually I think the post you quote went on to make a similar point. I read yesterday morning in the paper that the Goto Basic Linear Algebra Subroutines, by a Mr. Kazushige Goto, are still the most efficient library of functions for their purpose for use in supercomputing applications. Apparently hand-optimized assembler for specific processors. http://seattlepi.nwsource.com/business/250070_goto29.html (actually from the NY Times, apparently) Donn Cave, [EMAIL PROTECTED] -- http://mail.python.org/mailman/listinfo/python-list
