[llvm] [X86] Use the standard cmp+cmov for select (X != 0), -1, Y if we will be setting sbb to 0 anyway (PR #149672)

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AZero13 wrote:

> What is the motivation for this patch? Do you have results showing perf benefit, and for what targets please?

This comes up a lot in ucmp, especially on targets where sbb false dep causes stalls. This is the best way to do it. 

https://github.com/llvm/llvm-project/pull/149672