[llvm] [DA] Rewrite BanerjeeMIV test with safe APInt interval arithmetic (PR #207662)

[Ruoyu Qiu via llvm-commits]

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cabbaken wrote:

Added comments to describe the `BanerjeeInterval `, nullptr as negative/positive infinity, and reversed finite endpoints as the representation of an empty interval.

https://github.com/llvm/llvm-project/pull/207662