Add Morphism rsub with signature (req ==> req ==> req) as rsub_ext3.Ltac norm := gen_srewrite Rsth Reqe ARth.Ltac add_push := gen_add_push radd Rsth Reqe ARth.

Lemma ARgen_phiPOS_add : forall x y, gen_phiPOS1 (x + y) == (gen_phiPOS1 x) + (gen_phiPOS1 y).