{"ast_node_type":"other","tokens":[{"end":51,"kind":"keyword","start":0,"text":"///"}]}
    /// the postdominating upper bound in general.)
    /// (See `TransitiveRelation::postdom_upper_bound` for details on
    pub(crate) fn postdom_upper_bound(&self, fr1: RegionVid, fr2: RegionVid) -> RegionVid {