static av_always_inline void autocorrelate(const int x[40][2], SoftFloat phi[3][2][2], int lag)

{

    int i;

    int64_t real_sum, imag_sum;

    int64_t accu_re = 0, accu_im = 0;



    if (lag) {

        for (i = 1; i < 38; i++) {

            accu_re += (int64_t)x[i][0] * x[i+lag][0];

            accu_re += (int64_t)x[i][1] * x[i+lag][1];

            accu_im += (int64_t)x[i][0] * x[i+lag][1];

            accu_im -= (int64_t)x[i][1] * x[i+lag][0];

        }



        real_sum = accu_re;

        imag_sum = accu_im;



        accu_re += (int64_t)x[ 0][0] * x[lag][0];

        accu_re += (int64_t)x[ 0][1] * x[lag][1];

        accu_im += (int64_t)x[ 0][0] * x[lag][1];

        accu_im -= (int64_t)x[ 0][1] * x[lag][0];



        phi[2-lag][1][0] = autocorr_calc(accu_re);

        phi[2-lag][1][1] = autocorr_calc(accu_im);



        if (lag == 1) {

            accu_re = real_sum;

            accu_im = imag_sum;

            accu_re += (int64_t)x[38][0] * x[39][0];

            accu_re += (int64_t)x[38][1] * x[39][1];

            accu_im += (int64_t)x[38][0] * x[39][1];

            accu_im -= (int64_t)x[38][1] * x[39][0];



            phi[0][0][0] = autocorr_calc(accu_re);

            phi[0][0][1] = autocorr_calc(accu_im);

        }

    } else {

        for (i = 1; i < 38; i++) {

            accu_re += (int64_t)x[i][0] * x[i][0];

            accu_re += (int64_t)x[i][1] * x[i][1];

        }

        real_sum = accu_re;

        accu_re += (int64_t)x[ 0][0] * x[ 0][0];

        accu_re += (int64_t)x[ 0][1] * x[ 0][1];



        phi[2][1][0] = autocorr_calc(accu_re);



        accu_re = real_sum;

        accu_re += (int64_t)x[38][0] * x[38][0];

        accu_re += (int64_t)x[38][1] * x[38][1];



        phi[1][0][0] = autocorr_calc(accu_re);

    }

}
