[llvm] [ConstantFolding] Add ilogb in isMathLibCallNoop (PR #122582)

[Yingwei Zheng via llvm-commits]

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dtcxzyw wrote:

Please drop this unrelated change. I would like to see that calls to ilogb are eliminated in the test `llvm/test/Transforms/InstCombine/ilogb.ll`.


https://github.com/llvm/llvm-project/pull/122582