OpenBLAS/kernel/riscv64/amin_vector.c

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#include "common.h"

#ifdef RISCV64_ZVL256B
#       define LMUL m2
#       if defined(DOUBLE)
#               define ELEN 64
#       else
#               define ELEN 32
#       endif
#else
#       define LMUL m8
#       if defined(DOUBLE)
#               define ELEN 64
#       else
#               define ELEN 32
#       endif
#endif

#define _
#define JOIN2_X(x, y) x ## y
#define JOIN2(x, y) JOIN2_X(x, y)
#define JOIN(v, w, x, y, z) JOIN2( JOIN2( JOIN2( JOIN2( v, w ), x), y), z)

#define VSETVL          JOIN(__riscv_vsetvl,    _e,     ELEN,   LMUL,   _)
#define FLOAT_V_T       JOIN(vfloat,            ELEN,   LMUL,   _t,     _)
#define FLOAT_V_T_M1    JOIN(vfloat,            ELEN,   m1,     _t,     _)
#define VLEV_FLOAT      JOIN(__riscv_vle,       ELEN,   _v_f,   ELEN,   LMUL)
#define VLSEV_FLOAT     JOIN(__riscv_vlse,      ELEN,   _v_f,   ELEN,   LMUL)
#define VFREDMINVS_FLOAT JOIN(__riscv_vfredmin_vs_f,  ELEN,   LMUL,   _f, JOIN2( ELEN,   m1))
#define VFABS_FLOAT     JOIN(__riscv_vfabs,      _v_f,  ELEN,   LMUL,   _)
#define VFMVVF_FLOAT    JOIN(__riscv_vfmv,      _v_f_f  ELEN,   LMUL,   _)
#define VFMVVF_FLOAT_M1 JOIN(__riscv_vfmv,      _v_f_f, ELEN,   m1,     _)

FLOAT CNAME(BLASLONG n, FLOAT *x, BLASLONG inc_x)
{
        BLASLONG i=0, j=0;
        BLASLONG ix=0;
        FLOAT minf=0.0;
        if (n <= 0 || inc_x <= 0) return(minf);

        minf = *x;
        x += inc_x;
        --n;
        if (n == 0) return(minf);

        unsigned int gvl = 0;
        FLOAT_V_T v0, v1;
        FLOAT_V_T_M1 v_res;
        v_res = VFMVVF_FLOAT_M1(minf, 1);

        if(inc_x == 1){
                gvl = VSETVL(n);
                if(gvl <= n/2){
                        for(i=0,j=0; i<n/(gvl*2); i++){
                                v0 = VLEV_FLOAT(&x[j], gvl);
                                v1 = VLEV_FLOAT(&x[j+gvl], gvl);
                                v0 = VFABS_FLOAT(v0, gvl);
                                v1 = VFABS_FLOAT(v1, gvl);
                                v_res = VFREDMINVS_FLOAT(v0, v_res, gvl);
                                v_res = VFREDMINVS_FLOAT(v1, v_res, gvl);
                                j += gvl*2;
                        }
                }
                for(;j<n;){
                        gvl = VSETVL(n-j);
                        v0 = VLEV_FLOAT(&x[j], gvl);
                        v0 = VFABS_FLOAT(v0, gvl);
                        v_res = VFREDMINVS_FLOAT(v0, v_res, gvl);
                        j += gvl;
                }
        }else{
                gvl = VSETVL(n);
                BLASLONG stride_x = inc_x * sizeof(FLOAT);
                if(gvl <= n/2){
                        BLASLONG inc_xv = inc_x * gvl;
                        for(i=0,j=0; i<n/(gvl*2); i++){
                                v0 = VLSEV_FLOAT(&x[ix], stride_x, gvl);
                                v1 = VLSEV_FLOAT(&x[ix+inc_xv], stride_x, gvl);
                                v0 = VFABS_FLOAT(v0, gvl);
                                v1 = VFABS_FLOAT(v1, gvl);
                                v_res = VFREDMINVS_FLOAT(v0, v_res, gvl);
                                v_res = VFREDMINVS_FLOAT(v1, v_res, gvl);
                                j += gvl*2;
                                ix += inc_xv*2;
                        }
                }
                for(;j<n;){
                        gvl = VSETVL(n-j);
                        v0 = VLSEV_FLOAT(&x[j*inc_x], stride_x, gvl);
                        v0 = VFABS_FLOAT(v0, gvl);
                        v_res = VFREDMINVS_FLOAT(v0, v_res, gvl);
                        j += gvl;
                }
        }

        minf = EXTRACT_FLOAT(v_res);
        return(minf);
}