static bool range_within(struct bpf_reg_state *old,
			 struct bpf_reg_state *cur)
{
	return old->umin_value <= cur->umin_value &&
	       old->umax_value >= cur->umax_value &&
	       old->smin_value <= cur->smin_value &&
	       old->smax_value >= cur->smax_value;
}