[llvm] ValueTracking: Identify implied fp classes by general fcmp (PR #66505)

[Matt Arsenault via llvm-commits]

arsenm wrote:

> here is a repro from TF (I have not checked by hand, looks like some issues with fp ops) [tf_ir.txt](https://github.com/llvm/llvm-project/files/13558230/tf_ir.txt)

How do I reproduce this failure with opt? Running different opt levels and the obvious passes doesn't reproduce. Can you provide a pure opt reproducer, file and invocation? 

https://github.com/llvm/llvm-project/pull/66505