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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 m4
#       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_RVV(vsetvl),    _e,     ELEN,   LMUL,   _)
#define FLOAT_V_T       JOIN(vfloat,    	ELEN,   LMUL,   _t,     _)
#define FLOAT_V_M1_T    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)
#define VSEV_FLOAT      JOIN(RISCV_RVV(vse),       ELEN,   _v_f,   ELEN,   LMUL)
#define VSSEV_FLOAT     JOIN(RISCV_RVV(vsse),      ELEN,   _v_f,   ELEN,   LMUL)
#define VFMACCVF_FLOAT  JOIN(RISCV_RVV(vfmacc),    _vf_f, 	ELEN,   LMUL,   _)
#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,     _)

#ifdef RISCV_0p10_INTRINSICS
#define VFREDSUMVS_FLOAT(va, vb, gvl) JOIN(RISCV_RVV(vfredusum_vs_f),  ELEN,   LMUL,   _f, JOIN2( ELEN,   m1))(v_res, va, vb, gvl)
#else
#define VFREDSUMVS_FLOAT JOIN(RISCV_RVV(vfredusum_vs_f),  ELEN,   LMUL,   _f, JOIN2( ELEN,   m1))
#endif

int CNAME(BLASLONG n, BLASLONG dummy0, BLASLONG dummy1, FLOAT da, FLOAT *x, BLASLONG inc_x, FLOAT *y, BLASLONG inc_y, FLOAT *dummy, BLASLONG dummy2)
{
	BLASLONG i=0, j=0, jx=0, jy=0;
	unsigned int gvl = 0;
	FLOAT_V_T vx0, vx1;
	FLOAT_V_T vy0, vy1;
	BLASLONG stride_x, stride_y;

	if (n <= 0)  return(0);
	if (da == 0.0) return(0);

	if (inc_x == 1 && inc_y == 1) {

		gvl = VSETVL(n);

		if (gvl <= n/2) {
			for (i = 0, j=0; i < n/(2*gvl); i++, j+=2*gvl) {
				vx0 = VLEV_FLOAT(&x[j], gvl);
				vy0 = VLEV_FLOAT(&y[j], gvl);
				vy0 = VFMACCVF_FLOAT(vy0, da, vx0, gvl);
				VSEV_FLOAT(&y[j], vy0, gvl);

				vx1 = VLEV_FLOAT(&x[j+gvl], gvl);
				vy1 = VLEV_FLOAT(&y[j+gvl], gvl);
				vy1 = VFMACCVF_FLOAT(vy1, da, vx1, gvl);
				VSEV_FLOAT(&y[j+gvl], vy1, gvl);
			}
		}
		//tail
		for (; j < n; ) {
			gvl = VSETVL(n - j);
			vx0 = VLEV_FLOAT(&x[j], gvl);
			vy0 = VLEV_FLOAT(&y[j], gvl);
			vy0 = VFMACCVF_FLOAT(vy0, da, vx0, gvl);
			VSEV_FLOAT(&y[j], vy0, gvl);

			j += gvl;
		}
	}else if (inc_y == 1) {
		stride_x = inc_x * sizeof(FLOAT);
                gvl = VSETVL(n);
                if(gvl <= n/2){
                        BLASLONG inc_xv = inc_x * gvl;
                        for(i=0,j=0; i<n/(2*gvl); i++){
			        vx0 = VLSEV_FLOAT(&x[jx], stride_x, gvl);
                                vy0 = VLEV_FLOAT(&y[j], gvl);
                                vy0 = VFMACCVF_FLOAT(vy0, da, vx0, gvl);
                                VSEV_FLOAT(&y[j], vy0, gvl);

			        vx1 = VLSEV_FLOAT(&x[jx+inc_xv], stride_x, gvl);
                                vy1 = VLEV_FLOAT(&y[j+gvl], gvl);
                                vy1 = VFMACCVF_FLOAT(vy1, da, vx1, gvl);
                                VSEV_FLOAT(&y[j+gvl], vy1, gvl);

                                j += gvl * 2;
                                jx += inc_xv * 2;
                        }
                }
		for (; j<n; ) {
			gvl = VSETVL(n - j);
			vx0 = VLSEV_FLOAT(&x[j*inc_x], stride_x, gvl);
			vy0 = VLEV_FLOAT(&y[j], gvl);
			vy0 = VFMACCVF_FLOAT(vy0, da, vx0, gvl);
			VSEV_FLOAT(&y[j], vy0, gvl);
			j += gvl;
		}
	} else if (1 == inc_x && 0 != inc_y) {
		stride_y = inc_y * sizeof(FLOAT);
                gvl = VSETVL(n);
                if(gvl <= n/2){
                        BLASLONG inc_yv = inc_y * gvl;
                        for(i=0,j=0; i<n/(2*gvl); i++){
			        vx0 = VLEV_FLOAT(&x[j], gvl);
                                vy0 = VLSEV_FLOAT(&y[jy], stride_y, gvl);
                                vy0 = VFMACCVF_FLOAT(vy0, da, vx0, gvl);
                                VSSEV_FLOAT(&y[jy], stride_y, vy0, gvl);

			        vx1 = VLEV_FLOAT(&x[j+gvl], gvl);
                                vy1 = VLSEV_FLOAT(&y[jy+inc_yv], stride_y, gvl);
                                vy1 = VFMACCVF_FLOAT(vy1, da, vx1, gvl);
                                VSSEV_FLOAT(&y[jy+inc_yv], stride_y, vy1, gvl);

                                j += gvl * 2;
                                jy += inc_yv * 2;
                        }
                }
		for (; j<n; ) {
			gvl = VSETVL(n - j);
			vx0 = VLEV_FLOAT(&x[j], gvl);
			vy0 = VLSEV_FLOAT(&y[j*inc_y], stride_y, gvl);
			vy0 = VFMACCVF_FLOAT(vy0, da, vx0, gvl);
			VSSEV_FLOAT(&y[j*inc_y], stride_y, vy0, gvl);
			j += gvl;
		}
	} else if( 0 == inc_y ) {
	        BLASLONG stride_x = inc_x * sizeof(FLOAT);
	        size_t in_vl = VSETVL(n);
	        vy0 = VFMVVF_FLOAT( y[0], in_vl );

	        for (size_t vl; n > 0; n -= vl, x += vl*inc_x) {
	            vl = VSETVL(n);
	            vx0 = VLSEV_FLOAT(x, stride_x, vl);
	            vy0 = VFMACCVF_FLOAT(vy0, da, vx0, vl);
	        }
	        FLOAT_V_M1_T v_res = VFMVVF_FLOAT_M1( 0.0f, 1 );
	        v_res = VFREDSUMVS_FLOAT( vy0, v_res, in_vl );
	        y[0] = EXTRACT_FLOAT(v_res);
	}else{
		stride_x = inc_x * sizeof(FLOAT);
		stride_y = inc_y * sizeof(FLOAT);
                gvl = VSETVL(n);
                if(gvl <= n/2){
                        BLASLONG inc_xv = inc_x * gvl;
                        BLASLONG inc_yv = inc_y * gvl;
                        for(i=0,j=0; i<n/(2*gvl); i++){
			        vx0 = VLSEV_FLOAT(&x[jx], stride_x, gvl);
                                vy0 = VLSEV_FLOAT(&y[jy], stride_y, gvl);
                                vy0 = VFMACCVF_FLOAT(vy0, da, vx0, gvl);
                                VSSEV_FLOAT(&y[jy], stride_y, vy0, gvl);

			        vx1 = VLSEV_FLOAT(&x[jx+inc_xv], stride_x, gvl);
                                vy1 = VLSEV_FLOAT(&y[jy+inc_yv], stride_y, gvl);
                                vy1 = VFMACCVF_FLOAT(vy1, da, vx1, gvl);
                                VSSEV_FLOAT(&y[jy+inc_yv], stride_y, vy1, gvl);

                                j += gvl * 2;
                                jx += inc_xv * 2;
                                jy += inc_yv * 2;
                        }
                }
		for (; j<n; ) {
			gvl = VSETVL(n - j);
			vx0 = VLSEV_FLOAT(&x[j*inc_x], stride_x, gvl);
			vy0 = VLSEV_FLOAT(&y[j*inc_y], stride_y, gvl);
			vy0 = VFMACCVF_FLOAT(vy0, da, vx0, gvl);
			VSSEV_FLOAT(&y[j*inc_y], stride_y, vy0, gvl);
			j += gvl;
		}
	}
	return(0);
}