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From: | Andrew Crabtree <andrewc AT typhoon DOT rose DOT hp DOT com> |
Message-Id: | <199707101349.AA237002579@typhoon.rose.hp.com> |
Subject: | Re: your ma |
To: | chirayu AT giasbga DOT vsnl DOT net DOT in (Chirayu Krishnappa) |
Date: | Thu, 10 Jul 1997 6:49:39 PDT |
Cc: | djgpp AT delorie DOT com |
In-Reply-To: | <Pine.SV4.3.93.970710151909.18181A-100000@giasbga>; from "Chirayu Krishnappa" at Jul 10, 97 3:21 pm |
> i need to find out if a 4 byte (default) integer has an even number of 1's > in its binary representation or not. I need to operate on 15Mb data and do > it fast. shifts (<<) and & is quite slow. is there some lib. function to > do this? what is the fastest way to get it done? The only way I can think of to do this is to use the parity flag (Pentiums still have that - right :). I think (really not sure here), that if you so hat a bit of inline assembly that does an OR of the value with itself and the a jump on parity that should do the trick. HTH Andrew
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