[llvm] [ConstantFold] Fold `logb` and `logbf` when the input parameter is a constant value. (PR #111232)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,59 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt < %s -passes=instcombine -S | FileCheck %s
+
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arsenm wrote:

Test poison/inf/nan 

https://github.com/llvm/llvm-project/pull/111232