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2 mjames 1 
#include "ref.h"
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void ref_cmplx_dot_prod_f32(
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  float32_t * pSrcA,
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  float32_t * pSrcB,
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  uint32_t numSamples,
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  float32_t * realResult,
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  float32_t * imagResult)
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{
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        float32_t sumr, sumi;
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        uint32_t i;
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        sumr = 0;
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        sumi = 0;
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        for(i=0;i<numSamples*2;i+=2)
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        {
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                sumr += pSrcA[i] * pSrcB[i]   - pSrcA[i+1] * pSrcB[i+1];
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                sumi += pSrcA[i] * pSrcB[i+1] + pSrcA[i+1] * pSrcB[i];
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        }
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        *realResult = sumr;
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        *imagResult = sumi;
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}
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void ref_cmplx_dot_prod_q31(
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  q31_t * pSrcA,
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  q31_t * pSrcB,
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  uint32_t numSamples,
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  q63_t * realResult,
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  q63_t * imagResult)
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{
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        q63_t sumr, sumi;
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        uint32_t i;
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        sumr = 0;
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        sumi = 0;
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        for(i=0;i<numSamples*2;i+=2)
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        {
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                //shifting down 14 here to provide guard bits
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                sumr += (((q63_t)pSrcA[i] * pSrcB[i]  ) >> 14) - (((q63_t)pSrcA[i+1] * pSrcB[i+1]) >> 14);
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                sumi += (((q63_t)pSrcA[i] * pSrcB[i+1]) >> 14) + (((q63_t)pSrcA[i+1] * pSrcB[i]  ) >> 14);
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        }
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        *realResult = sumr;
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        *imagResult = sumi;
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}
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void ref_cmplx_dot_prod_q15(
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  q15_t * pSrcA,
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  q15_t * pSrcB,
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  uint32_t numSamples,
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  q31_t * realResult,
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  q31_t * imagResult)
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{
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        q63_t sumr, sumi;
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        uint32_t i;
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        sumr = 0;
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        sumi = 0;
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        for(i=0;i<numSamples*2;i+=2)
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        {
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                sumr += (q31_t)pSrcA[i] * pSrcB[i]   - (q31_t)pSrcA[i+1] * pSrcB[i+1];
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                sumi += (q31_t)pSrcA[i] * pSrcB[i+1] + (q31_t)pSrcA[i+1] * pSrcB[i];
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        }
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        //shifting down 6 at the end here because there are already 32 guard bits available, this method is more accurate
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        *realResult = (q31_t)(sumr >> 6);
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        *imagResult = (q31_t)(sumi >> 6);
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}