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#include "common.h"

#if defined(DSDOT)
double CNAME(BLASLONG n, FLOAT *x, BLASLONG inc_x, FLOAT *y, BLASLONG inc_y)
#else
FLOAT CNAME(BLASLONG n, FLOAT *x, BLASLONG inc_x, FLOAT *y, BLASLONG inc_y)
#endif
{
    double dot = 0.0;

    if ( n <= 0 ) return(dot);

    size_t vlmax = __riscv_vsetvlmax_e64m8();
    vfloat64m8_t vr = __riscv_vfmv_v_f_f64m8(0, vlmax);

    if(inc_x == 1 && inc_y == 1) {

        for (size_t vl; n > 0; n -= vl, x += vl, y += vl) {
            vl = __riscv_vsetvl_e64m8(n);

#if !defined(DOUBLE)
            vfloat32m4_t vx = __riscv_vle32_v_f32m4(x, vl);
            vfloat32m4_t vy = __riscv_vle32_v_f32m4(y, vl);

            vr = __riscv_vfwmacc_vv_f64m8_tu(vr, vx, vy, vl);
#else
            vfloat64m8_t vx = __riscv_vle64_v_f64m8(x, vl);
            vfloat64m8_t vy = __riscv_vle64_v_f64m8(y, vl);

            vr = __riscv_vfmacc_vv_f64m8_tu(vr, vx, vy, vl);
#endif
        }

    } else if (1 == inc_x) {
            
        BLASLONG stride_y = inc_y * sizeof(FLOAT);

        for (size_t vl; n > 0; n -= vl, x += vl, y += vl*inc_y) {
            vl = __riscv_vsetvl_e64m8(n);

#if !defined(DOUBLE)
            vfloat32m4_t vx = __riscv_vle32_v_f32m4(x, vl);
            vfloat32m4_t vy = __riscv_vlse32_v_f32m4(y, stride_y, vl);

            vr = __riscv_vfwmacc_vv_f64m8_tu(vr, vx, vy, vl);
#else
            vfloat64m8_t vx = __riscv_vle64_v_f64m8(x, vl);
            vfloat64m8_t vy = __riscv_vlse64_v_f64m8(y, stride_y, vl);

            vr = __riscv_vfmacc_vv_f64m8_tu(vr, vx, vy, vl);
#endif
        }
    } else if (1 == inc_y) {
            
        BLASLONG stride_x = inc_x * sizeof(FLOAT);

        for (size_t vl; n > 0; n -= vl, x += vl*inc_x, y += vl) {
            vl = __riscv_vsetvl_e64m8(n);

#if !defined(DOUBLE)
            vfloat32m4_t vx = __riscv_vlse32_v_f32m4(x, stride_x, vl);
            vfloat32m4_t vy = __riscv_vle32_v_f32m4(y, vl);

            vr = __riscv_vfwmacc_vv_f64m8_tu(vr, vx, vy, vl);
#else
            vfloat64m8_t vx = __riscv_vlse64_v_f64m8(x, stride_x, vl);
            vfloat64m8_t vy = __riscv_vle64_v_f64m8(y, vl);

            vr = __riscv_vfmacc_vv_f64m8_tu(vr, vx, vy, vl);
#endif
        }
    } else {
            
        BLASLONG stride_x = inc_x * sizeof(FLOAT);
        BLASLONG stride_y = inc_y * sizeof(FLOAT);

        for (size_t vl; n > 0; n -= vl, x += vl*inc_x, y += vl*inc_y) {
            vl = __riscv_vsetvl_e64m8(n);

#if !defined(DOUBLE)
            vfloat32m4_t vx = __riscv_vlse32_v_f32m4(x, stride_x, vl);
            vfloat32m4_t vy = __riscv_vlse32_v_f32m4(y, stride_y, vl);

            vr = __riscv_vfwmacc_vv_f64m8_tu(vr, vx, vy, vl);
#else
            vfloat64m8_t vx = __riscv_vlse64_v_f64m8(x, stride_x, vl);
            vfloat64m8_t vy = __riscv_vlse64_v_f64m8(y, stride_y, vl);

            vr = __riscv_vfmacc_vv_f64m8_tu(vr, vx, vy, vl);
#endif
        }
    }

    vfloat64m1_t vec_zero = __riscv_vfmv_v_f_f64m1(0, vlmax);
    vfloat64m1_t vec_sum = __riscv_vfredusum_vs_f64m8_f64m1(vr, vec_zero, vlmax);
    dot = __riscv_vfmv_f_s_f64m1_f64(vec_sum);

    return(dot);
}