OpenBLAS/kernel/riscv64/zamin_vector.c

/***************************************************************************
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#include "common.h"
#include <math.h>
#include <float.h>

#if !defined(DOUBLE)
#define VSETVL(n) vsetvl_e32m8(n)
#define VSETVL_MAX vsetvlmax_e32m1()
#define FLOAT_V_T vfloat32m8_t
#define FLOAT_V_T_M1 vfloat32m1_t
#define VFMVFS_FLOAT vfmv_f_s_f32m1_f32
#define VLSEV_FLOAT vlse32_v_f32m8
#define VFREDMINVS_FLOAT vfredmin_vs_f32m8_f32m1
#define MASK_T vbool4_t
#define VMFLTVF_FLOAT vmflt_vf_f32m8_b4
#define VFMVVF_FLOAT vfmv_v_f_f32m8
#define VFMVVF_FLOAT_M1 vfmv_v_f_f32m1
#define VFRSUBVF_MASK_FLOAT vfrsub_vf_f32m8_m
#define VFMINVV_FLOAT vfmin_vv_f32m8
#define VFADDVV_FLOAT vfadd_vv_f32m8
#else
#define VSETVL(n) vsetvl_e64m8(n)
#define VSETVL_MAX vsetvlmax_e32m1()
#define FLOAT_V_T vfloat64m8_t
#define FLOAT_V_T_M1 vfloat64m1_t
#define VFMVFS_FLOAT vfmv_f_s_f64m1_f64
#define VLSEV_FLOAT vlse64_v_f64m8
#define VFREDMINVS_FLOAT vfredmin_vs_f64m8_f64m1
#define MASK_T vbool8_t
#define VMFLTVF_FLOAT vmflt_vf_f64m8_b8
#define VFMVVF_FLOAT vfmv_v_f_f64m8
#define VFMVVF_FLOAT_M1 vfmv_v_f_f64m1
#define VFRSUBVF_MASK_FLOAT vfrsub_vf_f64m8_m
#define VFMINVV_FLOAT vfmin_vv_f64m8
#define VFADDVV_FLOAT vfadd_vv_f64m8
#endif

FLOAT CNAME(BLASLONG n, FLOAT *x, BLASLONG inc_x)
{
	BLASLONG i=0, j=0;
	BLASLONG ix=0;
	if (n <= 0 || inc_x <= 0) return(0.0);
	FLOAT minf=FLT_MAX;
        unsigned int gvl = 0;
        FLOAT_V_T v0, v1, v_min;
        FLOAT_V_T_M1 v_res, v_max;
        gvl = VSETVL_MAX;
        v_res = VFMVVF_FLOAT_M1(0, gvl);
        v_max = VFMVVF_FLOAT_M1(FLT_MAX, gvl);

        MASK_T mask0, mask1;
        BLASLONG stride_x = inc_x * sizeof(FLOAT) * 2;
        gvl = VSETVL(n);
        v_min = VFMVVF_FLOAT(FLT_MAX, gvl);
        BLASLONG inc_xv = inc_x * gvl * 2;
        for(; i<n/gvl; i++){
                v0 = VLSEV_FLOAT(&x[ix], stride_x, gvl);
                v1 = VLSEV_FLOAT(&x[ix+1], stride_x, gvl);
                mask0 = VMFLTVF_FLOAT(v0, 0, gvl);
                v0 = VFRSUBVF_MASK_FLOAT(mask0, v0, v0, 0, gvl);
                mask1 = VMFLTVF_FLOAT(v1, 0, gvl);
                v1 = VFRSUBVF_MASK_FLOAT(mask1, v1, v1, 0, gvl);

                v0 = VFADDVV_FLOAT(v0, v1, gvl);
                v_min = VFMINVV_FLOAT(v_min, v0, gvl);

                j += gvl;
                ix += inc_xv;
        }
        v_res = VFREDMINVS_FLOAT(v_res, v_min, v_max, gvl);
        minf = VFMVFS_FLOAT(v_res);

        if(j<n){
                gvl = VSETVL(n-j);
                v0 = VLSEV_FLOAT(&x[ix], stride_x, gvl);
                v1 = VLSEV_FLOAT(&x[ix+1], stride_x, gvl);
                mask0 = VMFLTVF_FLOAT(v0, 0, gvl);
                v0 = VFRSUBVF_MASK_FLOAT(mask0, v0, v0, 0, gvl);
                mask1 = VMFLTVF_FLOAT(v1, 0, gvl);
                v1 = VFRSUBVF_MASK_FLOAT(mask1, v1, v1, 0, gvl);
                v1 = VFADDVV_FLOAT(v0, v1, gvl);
                v_res = VFREDMINVS_FLOAT(v_res, v1, v_max, gvl);
                if(VFMVFS_FLOAT(v_res) < minf)
                        minf = VFMVFS_FLOAT(v_res);
        }
        return(minf);
}