[Mlir-commits] [mlir] [MLIR] Fix RemoveDeadValues handling of unreachable code (PR #153973)

[Mehdi Amini]

joker-eph wrote:

There is likely a problem with:

```
    // the execution of this pass might create new SSA values when erasing some
    // of the results of an op and we know that these new values are live
    // (because they weren't erased) and also their liveness is null because
    // liveness analysis ran before their creation.
```

But we don't have any test coverage for this!! :( 

https://github.com/llvm/llvm-project/pull/153973