OpenBLAS/kernel/riscv64/nrm2_vector.c

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#include "common.h"
#if !defined(DOUBLE)
#define VSETVL(n) vsetvl_e32m4(n)
#define VSETVL_MAX vsetvlmax_e32m1()
#define FLOAT_V_T vfloat32m4_t
#define FLOAT_V_T_M1 vfloat32m1_t
#define VLEV_FLOAT vle_v_f32m4
#define VLSEV_FLOAT vlse_v_f32m4
#define VFREDSUM_FLOAT vfredsum_vs_f32m4_f32m1
#define VFMACCVV_FLOAT vfmacc_vv_f32m4
#define VFMVVF_FLOAT vfmv_v_f_f32m4
#define VFMVVF_FLOAT_M1 vfmv_v_f_f32m1
#define VFDOTVV_FLOAT vfdot_vv_f32m4
#define ABS fabsf
#define MASK_T vbool8_t
#define VFRSUBVF_MASK_FLOAT vfrsub_vf_f32m4_m
#define VMFGTVF_FLOAT vmfgt_vf_f32m4_b8
#define VMFIRSTM vmfirst_m_b8
#define VFDIVVF_FLOAT vfdiv_vf_f32m4
#define VMFLTVF_FLOAT vmflt_vf_f32m4_b8
#define VFREDMAXVS_FLOAT vfredmax_vs_f32m4_f32m1
#else
#define VSETVL(n) vsetvl_e64m4(n)
#define VSETVL_MAX vsetvlmax_e64m1()
#define FLOAT_V_T vfloat64m4_t
#define FLOAT_V_T_M1 vfloat64m1_t
#define VLEV_FLOAT vle_v_f64m4
#define VLSEV_FLOAT vlse_v_f64m4
#define VFREDSUM_FLOAT vfredsum_vs_f64m4_f64m1
#define VFMACCVV_FLOAT vfmacc_vv_f64m4
#define VFMVVF_FLOAT vfmv_v_f_f64m4
#define VFMVVF_FLOAT_M1 vfmv_v_f_f64m1
#define VFDOTVV_FLOAT vfdot_vv_f64m4
#define ABS fabs
#define MASK_T vbool16_t
#define VFRSUBVF_MASK_FLOAT vfrsub_vf_f64m4_m
#define VMFGTVF_FLOAT vmfgt_vf_f64m4_b16
#define VMFIRSTM vmfirst_m_b16
#define VFDIVVF_FLOAT vfdiv_vf_f64m4
#define VMFLTVF_FLOAT vmflt_vf_f64m4_b16
#define VFREDMAXVS_FLOAT vfredmax_vs_f64m4_f64m1
#endif

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

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

        FLOAT_V_T vr, v0, v_zero;
        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);

        FLOAT scale = 0.0, ssq = 0.0;
        MASK_T mask;
        BLASLONG index = 0;
        if(inc_x == 1){
                gvl = VSETVL(n);
                vr = VFMVVF_FLOAT(0, gvl);
                v_zero = VFMVVF_FLOAT(0, gvl);
                for(i=0,j=0; i<n/gvl; i++){
                        v0 = VLEV_FLOAT(&x[j], gvl);
                        //fabs(vector)
                        mask = VMFLTVF_FLOAT(v0, 0, gvl);
                        v0 = VFRSUBVF_MASK_FLOAT(mask, v0, v0, 0, gvl);
                        //if scale change
                        mask = VMFGTVF_FLOAT(v0, scale, gvl);
                        index = VMFIRSTM(mask, gvl);
                        if(index == -1){//no elements greater than scale
                                if(scale != 0.0){
                                        v0 = VFDIVVF_FLOAT(v0, scale, gvl);
                                        vr = VFMACCVV_FLOAT(vr, v0, v0, gvl);
                                }
                        }else{//found greater element
                                //ssq in vector vr: vr[0]
                                v_res = VFREDSUM_FLOAT(v_res, vr, v_z0, gvl);
                                //total ssq before current vector
                                ssq += v_res[0];
                                //find max
                                v_res = VFREDMAXVS_FLOAT(v_res, v0, v_z0, gvl);
                                //update ssq before max_index
                                ssq = ssq * (scale/v_res[0])*(scale/v_res[0]);
                                //update scale
                                scale = v_res[0];
                                //ssq in vector vr
                                v0 = VFDIVVF_FLOAT(v0, scale, gvl);
                                vr = VFMACCVV_FLOAT(v_zero, v0, v0, gvl);
                        }
                        j += gvl;
                }
                //ssq in vector vr: vr[0]
                v_res = VFREDSUM_FLOAT(v_res, vr, v_z0, gvl);
                //total ssq now
                ssq += v_res[0];

                //tail
                if(j < n){
                        gvl = VSETVL(n-j);
                        v0 = VLEV_FLOAT(&x[j], gvl);
                        //fabs(vector)
                        mask = VMFLTVF_FLOAT(v0, 0, gvl);
                        v0 = VFRSUBVF_MASK_FLOAT(mask, v0, v0, 0, gvl);
                        //if scale change
                        mask = VMFGTVF_FLOAT(v0, scale, gvl);
                        index = VMFIRSTM(mask, gvl);
                        if(index == -1){//no elements greater than scale
                                if(scale != 0.0)
                                        v0 = VFDIVVF_FLOAT(v0, scale, gvl);
                        }else{//found greater element
                                //find max
                                v_res = VFREDMAXVS_FLOAT(v_res, v0, v_z0, gvl);
                                //update ssq before max_index
                                ssq = ssq * (scale/v_res[0])*(scale/v_res[0]);
                                //update scale
                                scale = v_res[0];
                                v0 = VFDIVVF_FLOAT(v0, scale, gvl);
                        }
                        vr = VFMACCVV_FLOAT(v_zero, v0, v0, gvl);
                        //ssq in vector vr: vr[0]
                        v_res = VFREDSUM_FLOAT(v_res, vr, v_z0, gvl);
                        //total ssq now
                        ssq += v_res[0];
                }
        }else{
                gvl = VSETVL(n);
                vr = VFMVVF_FLOAT(0, gvl);
                v_zero = VFMVVF_FLOAT(0, gvl);
                unsigned int stride_x = inc_x * sizeof(FLOAT);
                int idx = 0, inc_v = inc_x * gvl;
                for(i=0,j=0; i<n/gvl; i++){
                        v0 = VLSEV_FLOAT(&x[idx], stride_x, gvl);
                        //fabs(vector)
                        mask = VMFLTVF_FLOAT(v0, 0, gvl);
                        v0 = VFRSUBVF_MASK_FLOAT(mask, v0, v0, 0, gvl);
                        //if scale change
                        mask = VMFGTVF_FLOAT(v0, scale, gvl);
                        index = VMFIRSTM(mask, gvl);
                        if(index == -1){//no elements greater than scale
                                if(scale != 0.0){
                                        v0 = VFDIVVF_FLOAT(v0, scale, gvl);
                                        vr = VFMACCVV_FLOAT(vr, v0, v0, gvl);
                                }
                        }else{//found greater element
                                //ssq in vector vr: vr[0]
                                v_res = VFREDSUM_FLOAT(v_res, vr, v_z0, gvl);
                                //total ssq before current vector
                                ssq += v_res[0];
                                //find max
                                v_res = VFREDMAXVS_FLOAT(v_res, v0, v_z0, gvl);
                                //update ssq before max_index
                                ssq = ssq * (scale/v_res[0])*(scale/v_res[0]);
                                //update scale
                                scale = v_res[0];
                                //ssq in vector vr
                                v0 = VFDIVVF_FLOAT(v0, scale, gvl);
                                vr = VFMACCVV_FLOAT(v_zero, v0, v0, gvl);
                        }
                        j += gvl;
                        idx += inc_v;
                }
                //ssq in vector vr: vr[0]
                v_res = VFREDSUM_FLOAT(v_res, vr, v_z0, gvl);
                //total ssq now
                ssq += v_res[0];

                //tail
                if(j < n){
                        gvl = VSETVL(n-j);
                        v0 = VLSEV_FLOAT(&x[idx], stride_x, gvl);
                        //fabs(vector)
                        mask = VMFLTVF_FLOAT(v0, 0, gvl);
                        v0 = VFRSUBVF_MASK_FLOAT(mask, v0, v0, 0, gvl);
                        //if scale change
                        mask = VMFGTVF_FLOAT(v0, scale, gvl);
                        index = VMFIRSTM(mask, gvl);
                        if(index == -1){//no elements greater than scale
                                if(scale != 0.0)
                                        v0 = VFDIVVF_FLOAT(v0, scale, gvl);
                        }else{//found greater element
                                //find max
                                v_res = VFREDMAXVS_FLOAT(v_res, v0, v_z0, gvl);
                                //update ssq before max_index
                                ssq = ssq * (scale/v_res[0])*(scale/v_res[0]);
                                //update scale
                                scale = vr[0];
                                v0 = VFDIVVF_FLOAT(v0, scale, gvl);
                        }
                        vr = VFMACCVV_FLOAT(v_zero, v0, v0, gvl);
                        //ssq in vector vr: vr[0]
                        v_res = VFREDSUM_FLOAT(v_res, vr, v_z0, gvl);
                        //total ssq now
                        ssq += v_res[0];
                }
        }
	return(scale * sqrt(ssq));
}