[llvm] [ConstantFolding] Constant fold nextafter and nexttoward (PR #168794)

[Yingwei Zheng via llvm-commits]

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@@ -0,0 +1,226 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
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dtcxzyw wrote:

Can you please add tests for `nextafter(-0.0, 0.0) and nextafter(0.0, -0.0)`?

https://github.com/llvm/llvm-project/pull/168794