[llvm] [InstCombine] Fix fail to fold (A >> C1) Pred C2 if shr is used multple times #83430 (PR #83563)

[Nikita Popov via llvm-commits]

nikic wrote:

I think the only way to move forward with this would be to teach SPF about this pattern (I mean the one with comparison of the ashr operand, not the one with the non-canonical not).

https://github.com/llvm/llvm-project/pull/83563