Method should_suffix_scan

regex/src/exec.rs:1277–1283

Returns true if the program is amenable to suffix scanning. When this is true, as a heuristic, we assume it is OK to quickly scan for suffix literals and then do a *reverse* DFA match from any matches produced by the literal scan. (And then followed by a forward DFA search, since the previously found suffix literal maybe not actually be the end of a match.) This is a bit of a specialized optimiz

(&self)

    /// strings are generally rarer, so we only enable this optimization when
    /// we have a meaty suffix.
    fn should_suffix_scan(&self) -> bool {
        if self.suffixes.is_empty() {
            return false;
        }
        let lcs_len = self.suffixes.lcs().char_len();
        lcs_len >= 3 && lcs_len > self.dfa.prefixes.lcp().char_len()
    }
}

#[derive(Clone, Copy, Debug)]