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/* Compute the sum of the squares of a vector of signed shorts
* MMX-assisted version (also used on SSE)
* The SSE2 and MMX assist routines both operate on multiples of
* 8 words; they differ only in their alignment requirements (8 bytes
* for MMX, 16 bytes for SSE2)
* Copyright 2004 Phil Karn, KA9Q
* May be used under the terms of the GNU Lesser Public License (LGPL)
*/
long long sumsq_mmx_assist(signed short *,int);
long long sumsq_mmx(signed short *in,int cnt){
long long sum = 0;
/* Handle stuff before the next 8-byte boundary */
while(((int)in & 7) != 0 && cnt != 0){
sum += (long)in[0] * in[0];
in++;
cnt--;
}
sum += sumsq_mmx_assist(in,cnt);
in += cnt & ~7;
cnt &= 7;
/* Handle up to 7 words at end */
while(cnt != 0){
sum += (long)in[0] * in[0];
in++;
cnt--;
}
return sum;
}
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