[llvm] [LAA] Fix implicit trunc from int64 to int and losing info (PR #139553)

[via llvm-commits]

https://github.com/hiraditya approved this pull request.

LGTM, feel free to -1 if someone feels otherwise. As this fixes a bug and using APInt is a bit more involved.

https://github.com/llvm/llvm-project/pull/139553