[llvm] [ConstraintElim] Simplify cmp after uadd.sat/usub.sat (PR #135603)

[Nikita Popov via llvm-commits]

nikic wrote:

@el-ev The problem is the missing check for https://github.com/llvm/llvm-project/blob/31ddaef8d18d643ff4c343d03ddfe2edae7d22a2/llvm/lib/Transforms/Scalar/ConstraintElimination.cpp#L1140-L1141 for usub_sat.

https://github.com/llvm/llvm-project/pull/135603