OpenBLAS/kernel/riscv64/zamin_vector.c

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


#ifdef RISCV64_ZVL256B
#       define LMUL m2
#       if defined(DOUBLE)
#               define ELEN 64
#               define MLEN 32
#       else
#               define ELEN 32
#               define MLEN 16
#       endif
#else
#       define LMUL m8
#       if defined(DOUBLE)
#               define ELEN 64
#               define MLEN 8
#       else
#               define ELEN 32
#               define MLEN 4
#       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_RVV(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_RVV(vle),       ELEN,   _v_f,   ELEN,   LMUL)
#define VLSEV_FLOAT     JOIN(RISCV_RVV(vlse),      ELEN,   _v_f,   ELEN,   LMUL)
#ifdef RISCV_0p10_INTRINSICS
#define VFREDMINVS_FLOAT(va,vb,gvl) JOIN(RISCV_RVV(vfredmin_vs_f),  ELEN,   LMUL,   _f, JOIN2( ELEN,   m1)) (v_res, va, vb, gvl)
#define VFRSUBVF_MASK_FLOAT(va,vb,c,gvl) JOIN(RISCV_RVV(vfrsub),_vf_f,  ELEN,   LMUL,   _m) (va, vb, vb, c, gvl)
#else
#define VFREDMINVS_FLOAT JOIN(RISCV_RVV(vfredmin_vs_f),  ELEN,   LMUL,   _f, JOIN2( ELEN,   m1))
#define VFRSUBVF_MASK_FLOAT JOIN(RISCV_RVV(vfrsub),_vf_f,  ELEN,   LMUL,   _m)
#endif
#define MASK_T          JOIN(vbool,             MLEN,   _t,     _,      _)
#define VMFLTVF_FLOAT   JOIN(RISCV_RVV(vmflt_vf_f), ELEN,  LMUL,   _b,     MLEN)
#define VFMVVF_FLOAT    JOIN(RISCV_RVV(vfmv),      _v_f_f, ELEN,   LMUL,   _)
#define VFMVVF_FLOAT_M1 JOIN(RISCV_RVV(vfmv),      _v_f_f, ELEN,   m1,     _)
#define VFMINVV_FLOAT   JOIN(RISCV_RVV(vfmin),     _vv_f,  ELEN,   LMUL,   _)
#define VFADDVV_FLOAT   JOIN(RISCV_RVV(vfadd),     _vv_f,  ELEN,   LMUL,   _)

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_res = VFMVVF_FLOAT_M1(FLT_MAX, 1);

        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, 0, gvl);
                mask1 = VMFLTVF_FLOAT(v1, 0, gvl);
                v1 = VFRSUBVF_MASK_FLOAT(mask1, 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_min, v_res, gvl);

        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, 0, gvl);
                mask1 = VMFLTVF_FLOAT(v1, 0, gvl);
                v1 = VFRSUBVF_MASK_FLOAT(mask1, v1, 0, gvl);
                v1 = VFADDVV_FLOAT(v0, v1, gvl);
                v_res = VFREDMINVS_FLOAT(v1, v_res, gvl);
        }

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