[Gandiva] How to support overflow check and throw an exception in LLVM?

I deduce gandiva does not support overflow check from the following pic. Will it support that in the future? Besides, does somebody know how to detect overflow using LLVM api if not using function?

Besides, will decimal arith functions be supported in gandiva?

Start by reviewing Gandiva's current arithmetic support and the LLVM APIs related to overflow detection and exception handling. The issue names no files or tests; scope would need to be clarified for overflow checking, exception behavior, and decimal arithmetic before implementation and validation can be defined.

Written by the indexing model from the issue text.