public static boolean isOr(ExprNodeDesc expr) {
    if (expr instanceof ExprNodeGenericFuncDesc) {
      ExprNodeGenericFuncDesc exprNodeGenericFuncDesc = (ExprNodeGenericFuncDesc) expr;
      return (exprNodeGenericFuncDesc.getGenericUDF() instanceof GenericUDFOPOr);
    }
    return false;
  }
Checks wether the two expression sets have a common deterministic intersection.
ql/src/java/org/apache/hadoop/hive/ql/plan/ExprNodeDescUtils.java