Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!mit-eddie!bloom-beacon!tut.cis.ohio-state.edu!ucbvax!agate!saturn!ray
From: ray@saturn.ucsc.edu (Ray Swartz)
Newsgroups: comp.lang.c
Subject: What looks efficient may not be
Summary: ++i is not i++
Keywords: efficiency, increment operator
Message-ID: <7703@saturn.ucsc.edu>
Date: 27 May 89 15:24:07 GMT
Reply-To: ray@saturn.ucsc.edu (Ray Swartz)
Distribution: usa
Organization: University of California, Santa Cruz
Lines: 17

I recently was surprised to discover that 

     while (i < 500000)
	 ++i;


ran much faster than

     while (i < 500000))
	  i++;


The test ran on a 68020 based machine.  This test was run without using
the optimizer.  Here is yet another example that shows that optimizing
from a higher level language may backfire.
Incidentally, I realize the loops don't do anything, I was testing some 
alternatives ways of doing timing loops.