[llvm] [LV] Remove common extends and selects in CSE (PR #147731)

[Sam Tebbs via llvm-commits]

SamTebbs33 wrote:

> Looks like one of the tests is failing:
> 
> ```
> /home/gha/actions-runner/_work/llvm-project/llvm-project/llvm/test/Transforms/LoopVectorize/RISCV/vectorize-force-tail-with-evl-fixed-order-recurrence.ll:635:16: error: IF-EVL-NEXT: expected string not found in input
> ```

Strange, I don't see that locally. It's one of the LV tests so shouldn't need any extra projects enabled.

https://github.com/llvm/llvm-project/pull/147731