[llvm] [SCEV] Don't add predicates already implied by UnionPredicate. (PR #93397)

[Florian Hahn via llvm-commits]

https://github.com/fhahn commented:

> > Note that there exists logic elsewhere to avoid adding predicates if
> > they are already implied, but this logic misses cases when only some
> > predicates of a union predicate are implied by the current set of
> > predicates.
> 
> Where is that logic?

What I had in mind was https://github.com/llvm/llvm-project/blob/main/llvm/lib/Analysis/ScalarEvolution.cpp#L14803 but that's on a different code path, which looking at it now could probably also benefit from the same logic.

https://github.com/llvm/llvm-project/pull/93397