Function compute_entry_set 

pub fn compute_entry_set(
    chart: &CompiledChart,
    history: &History,
    ts: &[TransIdx],
    domains: &[Option<StateIdx>],
) -> EntryPlan

computeEntrySet. domains are the transitions’ domains as compute_exit_set saw them, before exitStates recorded history (see transition_domains): Appendix D recomputes them here from the history just recorded, which can move a domain below a state the exit left (a deep history of a parallel state with one region), and that state was then never entered again.