simplifyOneLevelPred (LNot (BinOp e1 LOr e2)) = BinOp (LNot e1) LAnd (LNot e2)
simplifyOneLevelPred (LNot (BinOp e1 LOr e2)) = BinOp (LNot e1) LAnd (LNot e2)
simplifyOneLevelPred (LNot (BinOp e1 LOr e2)) = BinOp (LNot e1) LAnd (LNot e2)