Hi Sun, Starting a thread on the mailing list around the query you had - https://github.com/apache/arrow/issues/4375.
Currently Gandiva does not support a user defined repository, we want to implement it sometime in the future but i am not sure when we will pick it up. In case you want to go ahead on the same, please share a specification around the same that others on the list can review and agree upon. Among the functions you called out, I think the first two should be already supported. I do not think we support the other two, but it is easier to add functions than to support an user registry at this point. Thx.
