[llvm] Add a pass to convert jump tables to switches. (PR #77709)

[David Li via llvm-commits]

david-xl wrote:

If the patch is intended as a size reduction optimization, it should be guarded under Os/Oz. Otherwise more performance data is needed. In particular performance with FDO (FDO does similar transformation but more selectively with value profile data.

https://github.com/llvm/llvm-project/pull/77709