Function query_feed 

pub(crate) fn query_feed<'tcx, C>(
    tcx: TyCtxt<'tcx>,
    dep_kind: DepKind,
    query_vtable: &QueryVTable<'tcx, C>,
    key: C::Key,
    value: C::Value,
)
where
    C: QueryCache,
    C::Key: DepNodeKey<'tcx>,

Common implementation of query feeding, used by define_feedable!.