SUBR_CLEAR
#define SUBR_CLEAR(ip,sy,sx,h,w) (ip)->grf->g_iteclear(ip,sy,sx,h,w)
#define SUBR_CLEAR(sc,sy,sx,h,w) (sc)->grf->g_iteclear(sc,sy,sx,h,w)
#define SUBR_CLEAR(ip,sy,sx,h,w) ip->isw->ite_clear(ip,sy,sx,h,w)