[llvm] [SLP]Convert compares from zexts, promoted to selects, to inversed op, if improves codegen (PR #181580)

[Alexey Bataev via llvm-commits]

alexey-bataev wrote:

> Second miscompile (at commit [5a4a1f4](https://github.com/llvm/llvm-project/commit/5a4a1f41b1dd1410feaf78457dec86edccb9ea99)) seen with: `opt -passes=slp-vectorizer bbi-115289.ll -S -o -`
> 
> The input adds 0 to the return value. The slp-vectorizer output adds 8. [bbi-115289.ll.gz](https://github.com/user-attachments/files/25439905/bbi-115289.ll.gz)
> 
> I can't help but feel that the original patch would have needed better testing to begin with and still does.
> 
> Now revert?

It was tested, but unfortunately, all these corner cases did not occur neither in SPECs/llvm-test-suite, nor in clang-llvm codebase. I'll fix all the corner cases ASAP

https://github.com/llvm/llvm-project/pull/181580