From:	"Arash Salarian" <arash DOT salarian AT epfl DOT ch>
Newsgroups:	comp.os.msdos.djgpp,comp.lang.c++
References:	<3CFCB642 DOT 252CFFF7 AT bigfoot DOT com>
Subject:	Re: Optimization and operator&&
Date:	Tue, 4 Jun 2002 17:22:05 +0200
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"Alex Vinokur" <alexvn AT bigfoot DOT com> wrote in message
news:3CFCB642 DOT 252CFFF7 AT bigfoot DOT com...
>
> ###############
> Windows98
> gcc/gpp 2.95.3
> ###############
>
>
> A program below measures performance (time) :
>   * of operator&& and operator+
>   * with automatic and static unsigned int
>   * with optimizations : No optimization, O1, O2, O3
>
> We can see that Optimization causes
>   an increase in elapsed time for operator&& .
> Any explanation?
>
> P.S Elapsed time of operator+ decreases.
>
> Thanks in advance.
>
> .....
>

Your solution of using systems "very low resolution" timer (which has
actually only a 55msec resolution) combined with very low iteration of the
main loop (only 1000 times) is the cause of this result. Try to re-write
your code with much higher iteration (more than 1 million at least) so that
the total execution time of the program becomes much much more in comparison
to 55msec resolution of the timer.....

hmmmmmm, but as I see, all this seems to be quite off topic here which is
Standard C++ language.....

Regards
Arash

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