static bool func_states_equal(struct bpf_verifier_env *env, struct bpf_func_state *old,
			      struct bpf_func_state *cur, bool exact)
static bool func_states_equal(struct bpf_verifier_env *env, struct bpf_func_state *old,
			      struct bpf_func_state *cur, enum exact_level exact)