[clang] [llvm] [llvm][AMDGPU] Fold `llvm.amdgcn.wavefrontsize` early (PR #114481)

[Matt Arsenault via llvm-commits]

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@@ -1,3 +1,4 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
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arsenm wrote:

The tests for this should go in test/InstCombine/AMDGPU 

https://github.com/llvm/llvm-project/pull/114481