TechRepublic member and frequent commenter Gerardo Tasistro sent in some very interesting PHP performance numbers. He compared the speed of two empty loops and discovered that, when using a calculation for the end condition, the loop ran about 25% faster than when using a comparison. For example:
for($i=0;$maxCount-$i;$i++) { }
If you’re running a tight loop with a lot of iterations, this little trick can give you enough extra performance to justify the non-standard coding.
J.Ja