OpenBLAS/kernel/riscv64/nrm2_vector_dot.c

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#include "common.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 VLEV_FLOAT vle32_v_f32m8
#define VLSEV_FLOAT vlse32_v_f32m8
#define VFMVFS_FLOAT vfmv_f_s_f32m1_f32
#define VFREDSUM_FLOAT vfredusum_vs_f32m8_f32m1
#define VFMACCVV_FLOAT vfmacc_vv_f32m8
#define VFMVVF_FLOAT vfmv_v_f_f32m8
#define VFMVVF_FLOAT_M1 vfmv_v_f_f32m1
#define VFDOTVV_FLOAT vfdot_vv_f32m8
#define ABS fabsf
#else
#define VSETVL(n) vsetvl_e64m8(n)
#define VSETVL_MAX vsetvlmax_e64m1()
#define FLOAT_V_T vfloat64m8_t
#define FLOAT_V_T_M1 vfloat64m1_t
#define VLEV_FLOAT vle64_v_f64m8
#define VLSEV_FLOAT vlse64_v_f64m8
#define VFMVFS_FLOAT vfmv_f_s_f64m1_f64
#define VFREDSUM_FLOAT vfredusum_vs_f64m8_f64m1
#define VFMACCVV_FLOAT vfmacc_vv_f64m8
#define VFMVVF_FLOAT vfmv_v_f_f64m8
#define VFMVVF_FLOAT_M1 vfmv_v_f_f64m1
#define VFDOTVV_FLOAT vfdot_vv_f64m8
#define ABS fabs
#endif

FLOAT CNAME(BLASLONG n, FLOAT *x, BLASLONG inc_x)
{
	BLASLONG i=0, j=0;
	double len = 0.0 ;

	if ( n <= 0 )  return(0.0);
        if(n == 1) return (ABS(x[0]));

        FLOAT_V_T vr, v0, v1;
        unsigned int gvl = 0;
        FLOAT_V_T_M1 v_res, v_z0;
        gvl = VSETVL_MAX;
        v_res = VFMVVF_FLOAT_M1(0, gvl);
        v_z0 = VFMVVF_FLOAT_M1(0, gvl);

        if(inc_x == 1){
                gvl = VSETVL(n);
                if(gvl < n/2){
                        vr = VFMVVF_FLOAT(0, gvl);
                        for(i=0,j=0; i<n/(2*gvl); i++){
                                v0 = VLEV_FLOAT(&x[j], gvl);
                                vr = VFMACCVV_FLOAT(vr, v0, v0, gvl);
                                j += gvl;

                                v1 = VLEV_FLOAT(&x[j], gvl);
                                vr = VFMACCVV_FLOAT(vr, v1, v1, gvl);
                                j += gvl;
                        }
                        v_res = VFREDSUM_FLOAT(v_res, vr, v_z0, gvl);
                        len += VFMVFS_FLOAT(v_res);
                }
                //tail
                for(;j < n;){
                        gvl = VSETVL(n-j);
                        v0 = VLEV_FLOAT(&x[j], gvl);
                        //v1 = 0
                        //v1 = VFMVVF_FLOAT(0, gvl);
                        //vr = VFDOTVV_FLOAT(v0, v0, gvl);
                        vr = VFMACCVV_FLOAT(v1, v0, v0, gvl);
                        v_res = VFREDSUM_FLOAT(v_res, vr, v_z0, gvl);
                        len += VFMVFS_FLOAT(v_res);

                        j += gvl;
                }
        }else{
                gvl = VSETVL(n);
                unsigned int stride_x = inc_x * sizeof(FLOAT);
                if(gvl < n/2){
                        vr = VFMVVF_FLOAT(0, gvl);
                        for(i=0,j=0; i<n/(2*gvl); i++){
                                v0 = VLSEV_FLOAT(&x[j*inc_x], stride_x, gvl);
                                vr = VFMACCVV_FLOAT(vr, v0, v0, gvl);
                                j += gvl;

                                v1 = VLSEV_FLOAT(&x[j*inc_x], stride_x, gvl);
                                vr = VFMACCVV_FLOAT(vr, v1, v1, gvl);
                                j += gvl;
                        }
                        v_res = VFREDSUM_FLOAT(v_res, vr, v_z0, gvl);
                        len += VFMVFS_FLOAT(v_res);
                }
                //tail
                for(;j < n;){
                        gvl = VSETVL(n-j);
                        v0 = VLSEV_FLOAT(&x[j*inc_x], stride_x, gvl);
                        //v1 = 0
                        //v1 = VFMVVF_FLOAT(0, gvl);
                        //vr = VFDOTVV_FLOAT(v0, v0, gvl);
                        vr = VFMACCVV_FLOAT(v1, v0, v0, gvl);
                        v_res = VFREDSUM_FLOAT(v_res, vr, v_z0, gvl);
                        len += VFMVFS_FLOAT(v_res);

                        j += gvl;
                }
        }
	return(sqrt(len));
}