#[global]
Instance Op_leb : BinOp leb :=
  {| TBOp := Z.leb; TBOpInj := leb_le |}.

(* Specifications: *)
Lemma eqb_eq : forall n m, (n =? m)%uint63 = (φ (n)%uint63 =? φ (m)%uint63)%Z.
Lemma eqb_eq : forall n m, (n =? m)%sint63 = (to_Z n =? to_Z m)%Z.