Definition binary_op_beq a b :=
match a, b with
    Oadd, Oadd
  | Osub, Osub
  | Omul, Omul
  | Odiv, Odiv
  | Omod, Omod
  | Oand, Oand
  | Oor, Oor
  | Oxor, Oxor
  | Oshl, Oshl
  | Oshr, Oshr
  | Oeq, Oeq
  | One, One
  | Olt, Olt
  | Ogt, Ogt
  | Ole, Ole
  | Oge, Oge => true
  | _, _ => false
end.

Lemma binary_op_beq_sound : forall a b, binary_op_beq a b = true -> a = b .