Method find_dfa_reverse_suffix

regex/src/exec.rs:823–853

reduces constant overhead

(
        &self,
        text: &[u8],
        start: usize,
    )

    /// matching engine should be used.
    #[inline(always)] // reduces constant overhead
    fn find_dfa_reverse_suffix(
        &self,
        text: &[u8],
        start: usize,
    ) -> dfa::Result<(usize, usize)> {
        use dfa::Result::*;

        let match_start = match self.exec_dfa_reverse_suffix(text, start) {
            None => return self.find_dfa_forward(text, start),
            Some(Match((start, _))) => start,
            Some(r) => return r,
        };
        // At this point, we've found a match. The only way to quit now
        // without a match is if the DFA gives up (seems unlikely).
        //
        // Now run the DFA forwards to find the proper end of the match.
        // (The suffix literal match can only indicate the earliest
        // possible end location, which may appear before the end of the
        // leftmost-first match.)
        match dfa::Fsm::forward(
            &self.ro.dfa,
            self.cache,
            false,
            text,
            match_start,
        ) {
            NoMatch(_) => panic!("BUG: reverse match implies forward match"),
            Quit => Quit,
            Match(e) => Match((match_start, e)),
        }
    }

    /// Executes the NFA engine to return whether there is a match or not.
    ///