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
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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