[clang] [llvm] [AMDGPU] Introduce asyncmark/wait intrinsics (PR #180467)

[Sameer Sahasrabuddhe via cfe-commits]

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@@ -1427,6 +1529,49 @@ void WaitcntBrackets::determineWaitForScore(InstCounterType T,
   }
 }
 
+AMDGPU::Waitcnt WaitcntBrackets::determineAsyncWait(unsigned N) {
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ssahasra wrote:

`N` corresponds to the the text use in the actual specification. It is the most meaningful choice at this point.

https://github.com/llvm/llvm-project/pull/180467