cseExpr env (App f a) = App (cseExpr env f) (tryForCSE env a)
cseExpr evn (Note InlineMe e) = Note InlineMe e -- See Note [INLINE and NOINLINE]
cseExpr env (Note n e) = Note n (cseExpr env e)
+cseExpr env (Cast e co) = Cast (cseExpr env e) co
cseExpr env (Lam b e) = let (env', b') = addBinder env b
in Lam b' (cseExpr env' e)
cseExpr env (Let bind e) = let (env', bind') = cseBind env bind