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#include "common.h"
#if !defined(DOUBLE)
#define VSETVL(n) RISCV_RVV(vsetvl_e32m8)(n)
#define VSETVL_MAX_M1 RISCV_RVV(vsetvlmax_e32m1)
#define FLOAT_V_T vfloat32m8_t
#define FLOAT_V_T_M1 vfloat32m1_t
#define VLEV_FLOAT RISCV_RVV(vle32_v_f32m8)
#define VLSEV_FLOAT RISCV_RVV(vlse32_v_f32m8)
#ifdef RISCV_0p10_INTRINSICS
#define VFREDSUM_FLOAT(va, vb, gvl) vfredusum_vs_f32m8_f32m1(v_res, va, vb, gvl)
#else
#define VFREDSUM_FLOAT RISCV_RVV(vfredusum_vs_f32m8_f32m1)
#endif
#define VFMULVV_FLOAT RISCV_RVV(vfmul_vv_f32m8)
#define VFMVVF_FLOAT RISCV_RVV(vfmv_v_f_f32m8)
#define VFMVVF_FLOAT_M1 RISCV_RVV(vfmv_v_f_f32m1)
#define xint_t int
#else
#define VSETVL(n) RISCV_RVV(vsetvl_e64m8)(n)
#define VSETVL_MAX_M1 RISCV_RVV(vsetvlmax_e64m1)
#define FLOAT_V_T vfloat64m8_t
#define FLOAT_V_T_M1 vfloat64m1_t
#define VLEV_FLOAT RISCV_RVV(vle64_v_f64m8)
#define VLSEV_FLOAT RISCV_RVV(vlse64_v_f64m8)
#ifdef RISCV_0p10_INTRINSICS
#define VFREDSUM_FLOAT(va, vb, gvl) vfredusum_vs_f64m8_f64m1(v_res, va, vb, gvl)
#else
#define VFREDSUM_FLOAT RISCV_RVV(vfredusum_vs_f64m8_f64m1)
#endif
#define VFMULVV_FLOAT RISCV_RVV(vfmul_vv_f64m8)
#define VFMVVF_FLOAT RISCV_RVV(vfmv_v_f_f64m8)
#define VFMVVF_FLOAT_M1 RISCV_RVV(vfmv_v_f_f64m1)
#define xint_t long long
#endif

int CNAME(BLASLONG m, BLASLONG n, BLASLONG dummy1, FLOAT alpha, FLOAT *a, BLASLONG lda, FLOAT *x, BLASLONG inc_x, FLOAT *y, BLASLONG inc_y, FLOAT *buffer)
{
    BLASLONG i = 0, j = 0, k = 0;
    BLASLONG ix = 0, iy = 0;
    FLOAT *a_ptr = a;
    FLOAT temp;

    FLOAT_V_T va, vr, vx;
    unsigned int gvl = 0;
    FLOAT_V_T_M1 v_res;
    size_t vlmax = VSETVL_MAX_M1();

#ifndef RISCV_0p10_INTRINSICS
    FLOAT_V_T va0, va1, va2, va3, vr0, vr1, vr2, vr3;
    FLOAT_V_T_M1 vec0, vec1, vec2, vec3;
    FLOAT *a_ptrs[4], *y_ptrs[4];
#endif

    if(inc_x == 1){
#ifndef RISCV_0p10_INTRINSICS
        BLASLONG anr = n - n % 4;
        for (; i < anr; i += 4) {
            gvl = VSETVL(m);
            j = 0;
            for (int l = 0; l < 4; l++) {
                a_ptrs[l] = a + (i + l) * lda;
                y_ptrs[l] = y + (i + l) * inc_y;
            }
            vec0 = VFMVVF_FLOAT_M1(0.0, vlmax);
            vec1 = VFMVVF_FLOAT_M1(0.0, vlmax);
            vec2 = VFMVVF_FLOAT_M1(0.0, vlmax);
            vec3 = VFMVVF_FLOAT_M1(0.0, vlmax);
            vr0 = VFMVVF_FLOAT(0.0, gvl);
            vr1 = VFMVVF_FLOAT(0.0, gvl);
            vr2 = VFMVVF_FLOAT(0.0, gvl);
            vr3 = VFMVVF_FLOAT(0.0, gvl);
            for (k = 0; k < m / gvl; k++) {
                va0 = VLEV_FLOAT(a_ptrs[0] + j, gvl);
                va1 = VLEV_FLOAT(a_ptrs[1] + j, gvl);
                va2 = VLEV_FLOAT(a_ptrs[2] + j, gvl);
                va3 = VLEV_FLOAT(a_ptrs[3] + j, gvl);

                vx = VLEV_FLOAT(x + j, gvl);
                vr0 = VFMULVV_FLOAT(va0, vx, gvl);
                vr1 = VFMULVV_FLOAT(va1, vx, gvl);
                vr2 = VFMULVV_FLOAT(va2, vx, gvl);
                vr3 = VFMULVV_FLOAT(va3, vx, gvl);
                // Floating-point addition does not satisfy the associative law, that is, (a + b) + c ≠ a + (b + c),
                // so piecewise multiplication and reduction must be performed inside the loop body.
                vec0 = VFREDSUM_FLOAT(vr0, vec0, gvl);
                vec1 = VFREDSUM_FLOAT(vr1, vec1, gvl);
                vec2 = VFREDSUM_FLOAT(vr2, vec2, gvl);
                vec3 = VFREDSUM_FLOAT(vr3, vec3, gvl);
                j += gvl;
            }
            if (j < m) {
                gvl = VSETVL(m - j);
                va0 = VLEV_FLOAT(a_ptrs[0] + j, gvl);
                va1 = VLEV_FLOAT(a_ptrs[1] + j, gvl);
                va2 = VLEV_FLOAT(a_ptrs[2] + j, gvl);
                va3 = VLEV_FLOAT(a_ptrs[3] + j, gvl);

                vx = VLEV_FLOAT(x + j, gvl);
                vr0 = VFMULVV_FLOAT(va0, vx, gvl);
                vr1 = VFMULVV_FLOAT(va1, vx, gvl);
                vr2 = VFMULVV_FLOAT(va2, vx, gvl);
                vr3 = VFMULVV_FLOAT(va3, vx, gvl);
                vec0 = VFREDSUM_FLOAT(vr0, vec0, gvl);
                vec1 = VFREDSUM_FLOAT(vr1, vec1, gvl);
                vec2 = VFREDSUM_FLOAT(vr2, vec2, gvl);
                vec3 = VFREDSUM_FLOAT(vr3, vec3, gvl);
            }
            *y_ptrs[0] += alpha * (FLOAT)(EXTRACT_FLOAT(vec0));
            *y_ptrs[1] += alpha * (FLOAT)(EXTRACT_FLOAT(vec1));
            *y_ptrs[2] += alpha * (FLOAT)(EXTRACT_FLOAT(vec2));
            *y_ptrs[3] += alpha * (FLOAT)(EXTRACT_FLOAT(vec3));
        }
        // deal with the tail
        for (; i < n; i++) {
            v_res = VFMVVF_FLOAT_M1(0, vlmax);
            gvl = VSETVL(m);
            j = 0;
            a_ptrs[0] = a + i * lda;
            y_ptrs[0] = y + i * inc_y;
            vr0 = VFMVVF_FLOAT(0, gvl);
            for (k = 0; k < m / gvl; k++) {
                va0 = VLEV_FLOAT(a_ptrs[0] + j, gvl);
                vx = VLEV_FLOAT(x + j, gvl);
                vr0 = VFMULVV_FLOAT(va0, vx, gvl);
                v_res = VFREDSUM_FLOAT(vr0, v_res, gvl);
                j += gvl;
            }
            if (j < m) {
                gvl = VSETVL(m - j);
                va0 = VLEV_FLOAT(a_ptrs[0] + j, gvl);
                vx = VLEV_FLOAT(x + j, gvl);
                vr0 = VFMULVV_FLOAT(va0, vx, gvl);
                v_res = VFREDSUM_FLOAT(vr0, v_res, gvl);
            }
            *y_ptrs[0] += alpha * (FLOAT)(EXTRACT_FLOAT(v_res));
        }
#else
    for(i = 0; i < n; i++){
        v_res = VFMVVF_FLOAT_M1(0, 1);
        gvl = VSETVL(m);
        j = 0;
        vr = VFMVVF_FLOAT(0, gvl);
        for(k = 0; k < m/gvl; k++){
            va = VLEV_FLOAT(&a_ptr[j], gvl);
            vx = VLEV_FLOAT(&x[j], gvl);
            vr = VFMULVV_FLOAT(va, vx, gvl);                // could vfmacc here and reduce outside loop
            v_res = VFREDSUM_FLOAT(vr, v_res, gvl);         // but that reordering diverges far enough from scalar path to make tests fail
            j += gvl;
        }
        if(j < m){
            gvl = VSETVL(m-j);
            va = VLEV_FLOAT(&a_ptr[j], gvl);
            vx = VLEV_FLOAT(&x[j], gvl);
            vr = VFMULVV_FLOAT(va, vx, gvl);
            v_res = VFREDSUM_FLOAT(vr, v_res, gvl);
        }
        temp = (FLOAT)EXTRACT_FLOAT(v_res);
        y[iy] += alpha * temp;


        iy += inc_y;
        a_ptr += lda;
    }
#endif
    } else {
        BLASLONG stride_x = inc_x * sizeof(FLOAT);
        for(i = 0; i < n; i++){
            v_res = VFMVVF_FLOAT_M1(0, 1);
            gvl = VSETVL(m);
            j = 0;
            ix = 0;
            vr = VFMVVF_FLOAT(0, gvl);
            for(k = 0; k < m/gvl; k++){
                va = VLEV_FLOAT(&a_ptr[j], gvl);
                vx = VLSEV_FLOAT(&x[ix], stride_x, gvl);
                vr = VFMULVV_FLOAT(va, vx, gvl);
                v_res = VFREDSUM_FLOAT(vr, v_res, gvl);
                j += gvl;
                ix += inc_x * gvl;
            }
            if(j < m){
                gvl = VSETVL(m-j);
                va = VLEV_FLOAT(&a_ptr[j], gvl);
                vx = VLSEV_FLOAT(&x[ix], stride_x, gvl);
                vr = VFMULVV_FLOAT(va, vx, gvl);
                v_res = VFREDSUM_FLOAT(vr, v_res, gvl);
                }
                temp = (FLOAT)EXTRACT_FLOAT(v_res);
                y[iy] += alpha * temp;


                iy += inc_y;
                a_ptr += lda;
            }
        }

    return (0);
}