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#include "common.h"
#include <float.h>

#if !defined(DOUBLE)
#define VSETVL(n)               __riscv_vsetvl_e32m8(n)
#define VSETVL_MAX              __riscv_vsetvlmax_e32m8()
#define VSETVL_MAX_M1           __riscv_vsetvlmax_e32m1()
#define FLOAT_V_T               vfloat32m8_t
#define FLOAT_V_T_M1            vfloat32m1_t
#define VLEV_FLOAT              __riscv_vle32_v_f32m8
#define VLSEV_FLOAT             __riscv_vlse32_v_f32m8
#define VFREDMAXVS_FLOAT        __riscv_vfredmax_vs_f32m8_f32m1
#define VFMVVF_FLOAT            __riscv_vfmv_v_f_f32m8
#define VFMVVF_FLOAT_M1         __riscv_vfmv_v_f_f32m1
#define VFMAXVV_FLOAT_TU        __riscv_vfmax_vv_f32m8_tu
#define VFMVFS_FLOAT_M1         __riscv_vfmv_f_s_f32m1_f32
#else
#define VSETVL(n)               __riscv_vsetvl_e64m8(n)
#define VSETVL_MAX              __riscv_vsetvlmax_e64m8()
#define VSETVL_MAX_M1           __riscv_vsetvlmax_e64m1()
#define FLOAT_V_T               vfloat64m8_t
#define FLOAT_V_T_M1            vfloat64m1_t
#define VLEV_FLOAT              __riscv_vle64_v_f64m8
#define VLSEV_FLOAT             __riscv_vlse64_v_f64m8
#define VFREDMAXVS_FLOAT        __riscv_vfredmax_vs_f64m8_f64m1
#define VFMVVF_FLOAT            __riscv_vfmv_v_f_f64m8
#define VFMVVF_FLOAT_M1         __riscv_vfmv_v_f_f64m1
#define VFMAXVV_FLOAT_TU        __riscv_vfmax_vv_f64m8_tu
#define VFMVFS_FLOAT_M1         __riscv_vfmv_f_s_f64m1_f64
#endif

FLOAT CNAME(BLASLONG n, FLOAT *x, BLASLONG inc_x)
{
    FLOAT maxf = 0.0;

    if (n <= 0 || inc_x <= 0) return(maxf);

    FLOAT_V_T vx, vmax;
    FLOAT_V_T_M1 v_res;

    v_res = VFMVVF_FLOAT_M1(-FLT_MAX, VSETVL_MAX_M1);
    size_t vlmax = VSETVL_MAX;
    vmax = VFMVVF_FLOAT(-FLT_MAX, vlmax);

    if(inc_x == 1) {

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

            vx = VLEV_FLOAT(x, vl);
            vmax = VFMAXVV_FLOAT_TU(vmax, vmax, vx, vl);
       }

    } else {

        BLASLONG stride_x = inc_x * sizeof(FLOAT);

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

            vx = VLSEV_FLOAT(x, stride_x, vl);
            vmax = VFMAXVV_FLOAT_TU(vmax, vmax, vx, vl);
        }

    }

    v_res = VFREDMAXVS_FLOAT(vmax, v_res, vlmax);
    maxf = VFMVFS_FLOAT_M1(v_res);

    return(maxf);
}
