digraph {
        graph [label="Encoder state machine", labelloc="t"]
        start [style="invis", shape="point"]
        not_full
        filled
        search
        yield_tag_bit
        yield_literal
        yield_br_length
        yield_br_index
        save_backlog
        flush_bits
        done [peripheries=2]

        start->not_full [label="start"]

        not_full->not_full [label="sink(), not full", color="blue"]
        not_full->filled [label="sink(), buffer is full", color="blue"]
        not_full->filled [label="finish(), set is_finished", color="blue"]

        filled->search [label="indexing (if any)"]

        search->yield_tag_bit [label="literal"]
        search->yield_tag_bit [label="match found"]
        search->save_backlog [label="input exhausted, not finishing"]
        search->flush_bits [label="input exhausted, finishing"]

        yield_tag_bit->yield_tag_bit [label="poll(), full buf", color="red"]
        yield_tag_bit->yield_literal [label="poll(), literal", color="red"]
        yield_tag_bit->yield_br_index [label="poll(), match", color="red"]

        yield_literal->yield_literal [label="poll(), full buf", color="red"]
        yield_literal->search [label="done"]

        yield_br_index->yield_br_index [label="poll(), full buf", color="red"]
        yield_br_index->yield_br_length [label="poll()", color="red"]

        yield_br_length->yield_br_length [label="poll(), full buf", color="red"]
        yield_br_length->search [label="done"]

        save_backlog->not_full [label="expect more input"]

        flush_bits->flush_bits [label="poll(), full buf", color="red"]
        flush_bits->done [label="poll(), flushed", color="red"]
        flush_bits->done [label="no more output"]
}