Re: checking a loop execution

[Charles Hixson <charleshixsn@earthlink.net>]

tmoran@bix.com wrote:

> >I could add a control variable (ivar, in my example) to take care of the
> >iteration number when exiting, but that would decrease the peformance
> >of my algorithm
>
>   Your loop as shown evaluates <condition>, and increments and tests
> i and branches, up to 10 times, but assigns "ivar := i;" just once,
> so setting ivar is a small part of the total time.

I thought that compilers automatically detected this kind of optimization.
Would unrolling the loop by hand actually be a good idea?  Or would it be an
optimization that defeated itself as frequently as it helped?  (Actually, my
expectation would be that it would defeat itself more often than it helped.)