hello,in box.c function dx_box_iou,why add twice grad when Iw<=0||Ih<=0

[zzk2021]

if (iou_loss == GIOU) {
      if (giou_C > 0) {
        // apply "C" term from gIOU
        p_dt += ((giou_C * dU_wrt_t) - (U * dC_wrt_t)) / (giou_C * giou_C);
        p_db += ((giou_C * dU_wrt_b) - (U * dC_wrt_b)) / (giou_C * giou_C);
        p_dl += ((giou_C * dU_wrt_l) - (U * dC_wrt_l)) / (giou_C * giou_C);
        p_dr += ((giou_C * dU_wrt_r) - (U * dC_wrt_r)) / (giou_C * giou_C);
      }
      **if (Iw<=0||Ih<=0) {
        p_dt = ((giou_C * dU_wrt_t) - (U * dC_wrt_t)) / (giou_C * giou_C);
        p_db = ((giou_C * dU_wrt_b) - (U * dC_wrt_b)) / (giou_C * giou_C);
        p_dl = ((giou_C * dU_wrt_l) - (U * dC_wrt_l)) / (giou_C * giou_C);
        p_dr = ((giou_C * dU_wrt_r) - (U * dC_wrt_r)) / (giou_C * giou_C);
      }**
    }

if (iou_loss == CIOU) {
    float ar_gt = truth.w / truth.h;
        float ar_pred = pred.w / pred.h;
        float ar_loss = 4 / (M_PI * M_PI) * (atan(ar_gt) - atan(ar_pred)) * (atan(ar_gt) - atan(ar_pred));
    float alpha = ar_loss / (1 - I/U + ar_loss + 0.000001);
    float ar_dw=8/(M_PI*M_PI)*(atan(ar_gt)-atan(ar_pred))*pred.h;
        float ar_dh=-8/(M_PI*M_PI)*(atan(ar_gt)-atan(ar_pred))*pred.w;
        if (C > 0) {
        // dar*
            p_dx += (2*(truth.x-pred.x)*C-(2*Cw*dCw_dx+2*Ch*dCh_dx)*S) / (C * C);
            p_dy += (2*(truth.y-pred.y)*C-(2*Cw*dCw_dy+2*Ch*dCh_dy)*S) / (C * C);
            p_dw += (2*Cw*dCw_dw+2*Ch*dCh_dw)*S / (C * C) + alpha * ar_dw;
            p_dh += (2*Cw*dCw_dh+2*Ch*dCh_dh)*S / (C * C) + alpha * ar_dh;
        }
    **if (Iw<=0||Ih<=0){
            p_dx = (2*(truth.x-pred.x)*C-(2*Cw*dCw_dx+2*Ch*dCh_dx)*S) / (C * C);
            p_dy = (2*(truth.y-pred.y)*C-(2*Cw*dCw_dy+2*Ch*dCh_dy)*S) / (C * C);
            p_dw = (2*Cw*dCw_dw+2*Ch*dCh_dw)*S / (C * C) + alpha * ar_dw;
            p_dh = (2*Cw*dCw_dh+2*Ch*dCh_dh)*S / (C * C) + alpha * ar_dh;
        }**
    }

I want to know because I am writing my own iou loss,thanks

[zzk2021]

I was wrong sorry