in_sleepable
bool in_sleepable;
if (old->in_sleepable != cur->in_sleepable)
in_sleepable(env);
return in_sleepable(env);
if (sleepable && !in_sleepable(env)) {
dst_state->in_sleepable = src->in_sleepable;
state->in_sleepable = env->prog->sleepable;
elem->st.in_sleepable = is_sleepable;
return env->cur_state->in_sleepable;
!in_sleepable(env);