[llvm] Port CodeGenPrepare to new pass manager (and BasicBlockSectionsProfil… (PR #75380)

[Nick Anderson via llvm-commits]

nickleus27 wrote:

I am new to llvm-project and would appreciate any suggestions, especially on what is needed to port `BasicBlockSectionsProfileReader` to `BasicBlockSectionsProfileReaderAnalysis`. Currently, I am reading the docs at the bottom of [Contributing](https://llvm.org/docs/Contributing.html) to understand how the `.ll` tests work and how to debug failing tests. I pushed this `Draft PR` in case anyone has suggestions.

https://github.com/llvm/llvm-project/pull/75380