/* Compute the sum of the squares of a vector of signed shorts
|
|
* 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_sse2_assist(signed short *,int);
|
|
long long sumsq_sse2(signed short *in,int cnt){
|
long long sum = 0;
|
|
/* Handle stuff before the next 8-byte boundary */
|
while(((int)in & 15) != 0 && cnt != 0){
|
sum += (long)in[0] * in[0];
|
in++;
|
cnt--;
|
}
|
sum += sumsq_sse2_assist(in,cnt);
|
in += cnt & ~7;
|
cnt &= 7;
|
|
/* Handle up to 7 trailing words */
|
while(cnt != 0){
|
sum += (long)in[0] * in[0];
|
in++;
|
cnt--;
|
}
|
return sum;
|
}
|
