Re: Restrict qualified pointers in C

Your example didn't look like a good candidate for aggressive
optimization. How about this:

/* not tested */
void smear(int n, const float * restrict in, float * restrict out)
{
int i;
out[0]= ( in[0] + 2*in[1] )/3.f;
for(i= 1; i<n-1; i++) {
out[i]= ( in[i-1] + in[i] + in[i + 1] )/3.f;
}
out[n-1]= ( 2*in[n-2] + in[n-1] )/3.f;
}

(I think the "in" pointer doesn't need restrict, but I don't want
to spend time thinking about it.)

--
pa at panix dot com
.

Relevant Pages

  • Re: Inconsistent Program Results
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    (comp.lang.c)
  • Re: What does restrict mean?
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  • Re: Inconsistent Program Results
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