nft_rbtree_cmp
if (nft_rbtree_cmp(set, rbe, first_elem) < 0)
d = nft_rbtree_cmp(set, rbe, new);
d = nft_rbtree_cmp(set, rbe, new);
if (nft_rbtree_cmp(set, rbe_ge, new) != 0) {
if (rbe_ge && !nft_rbtree_cmp(set, new, rbe_ge) &&
if (rbe_le && !nft_rbtree_cmp(set, new, rbe_le) &&
d = nft_rbtree_cmp(set, rbe, new);