/* unoptimized
double sumDBIndicies(double* input1, IndiciesInput indicies)
{
    double accumulate = 0;
    for(unsigned int i = 0; i < indicies.nSingleIndicies; i++)
    {
        accumulate += input1[indicies.singleIndicies[i]];
    }
    for(unsigned int i = 0; i < indicies.nRanges; i++)
    {
        for(double* address = indicies.rangeStartPositions[i] + input1; address < indicies.rangeStartPositions[i] + input1 + indicies.rangeLengths[i]; address++)
        {
            accumulate += *address;
        }
    }
    return accumulate;
}
*/
double sumDBIndicies(double* input1, IndiciesInput indicies)
{
    double accumulate = 0;
    for(unsigned int i = 0; i < indicies.nSingleIndicies; i++)
    {
        accumulate += input1[indicies.singleIndicies[i]];
    }
    for(unsigned int i = 0; i < indicies.nRanges; i++)
    {
        unsigned int masked = indicies.rangeLengths[i] & ~0xF;
        double* address = indicies.rangeStartPositions[i] + input1;
        for(; address + 15 < indicies.rangeStartPositions[i] + input1 + masked; address+=16)
        {
            __m128d result1 = _mm_add_pd(_mm_load_pd(address), _mm_load_pd(address+2));
            __m128d result2 = _mm_add_pd(_mm_load_pd(address+4), _mm_load_pd(address+6));
            __m128d result3 = _mm_add_pd(_mm_load_pd(address+8), _mm_load_pd(address+10));
            __m128d result4 = _mm_add_pd(_mm_load_pd(address+12), _mm_load_pd(address+14));

            //now aggregate those
            __m128d result5 = _mm_add_pd(result1, result2);
            __m128d result6 = _mm_add_pd(result3, result4);

            __m128d result7 = _mm_add_pd(result5, result6);

            double output[8];
            double* aligned = (double*)((size_t)(output + 4) & ~0xF);
            _mm_store_pd(aligned, result7);
            accumulate += aligned[0] + aligned[1];
        }
        switch(indicies.rangeLengths[i] % 16)
        {
            case 15: accumulate += address[14];
            case 14: accumulate += address[13];
            case 13: accumulate += address[12];
            case 12: accumulate += address[11];
            case 11: accumulate += address[10];
            case 10: accumulate += address[9];
            case 9:  accumulate += address[8];
            case 8:  accumulate += address[7];
            case 7:  accumulate += address[6];
            case 6:  accumulate += address[5];
            case 5:  accumulate += address[4];
            case 4:  accumulate += address[3];
            case 3:  accumulate += address[2];
            case 2:  accumulate += address[1];
            case 1:  accumulate += address[0];
            case 0: break;

        }
    }
    return accumulate;
}