radix4_addr_entry
#define LRADIX4_ITEM_SZ roundup2(sizeof(struct radix4_addr_entry), 64)
struct radix4_addr_entry *ent;
ent = (struct radix4_addr_entry *)(rn_match(&addr4, &rnh->rh));
struct radix4_addr_entry *ae;
ae = (struct radix4_addr_entry *)(lr->rt_base + lr->num_items * LRADIX4_ITEM_SZ);