[llvm] [AMDGPU] Factor out common code from SIInsertWaitcnts (PR #83018)

[Jay Foad via llvm-commits]

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@@ -0,0 +1,1393 @@
+//===-- AMDGPUWaitCountUtils.cpp ------------------------------------------===//
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jayfoad wrote:

I think the `Utils` directory is only for things shared between codegen and asm/dis. This should go in the main `AMDGPU` directory.

https://github.com/llvm/llvm-project/pull/83018