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raggi/duffcpy.c

Created February 19, 2013 09:22
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duffcpy.c
switch (count % 8)
{
case 0:;
<D3492>:;
*to++ = *from++ ;
case 7:;
*to++ = *from++ ;
case 6:;
*to++ = *from++ ;
case 5:;
*to++ = *from++ ;
case 4:;
*to++ = *from++ ;
case 3:;
*to++ = *from++ ;
case 2:;
*to++ = *from++ ;
case 1:;
*to++ = *from++ ;
if ( --n > 0) goto <D3492>; else goto <D3493>;
<D3493>:;
}
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raggi commented Feb 19, 2013

The GCC IR for a Duffs device turns the do while into a goto in stage 3. Go figure.

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