Function rustc_trait_selection::traits::coherence::negative_impl

fn negative_impl<'tcx>(
    tcx: TyCtxt<'tcx>,
    impl1_def_id: DefId,
    impl2_def_id: DefId
) -> bool

Given impl1 and impl2 check if both impls are never satisfied by a common type (including where-clauses) If so, return true, they are disjoint and false otherwise.