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