From:	ao950 AT FreeNet DOT Carleton DOT CA (Paul Derbyshire)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Allegro ex11.c
Date:	16 Feb 1998 09:18:05 GMT
Organization:	The National Capital FreeNet
Lines:	22
Message-ID:	<6c908d$1mj@freenet-news.carleton.ca>
References:	<34DF7294 DOT 21D0 AT home DOT com> <34e39746 DOT 1884750 AT news DOT compusmart DOT ab DOT ca> <34E7EFA0 DOT 6DF9E92 AT alcyone DOT com>
Reply-To:	ao950 AT FreeNet DOT Carleton DOT CA (Paul Derbyshire)
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To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Erik Max Francis (max AT alcyone DOT com) writes:

> x%n is the same as x&(n - 1), when n is a power of 2.
> 
> Bitwise operations are much, much faster than integer division operators
> (/, %).

I sincerely hope GCC's optimizer is smart enough to silently use a
bitshift when optimizing

int x;
...
y = x % 8;

for instance.

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Paul Derbyshire ao950 AT freenet DOT carleton DOT ca pgd73 AT hotmail DOT com

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