[llvm] [AMDGPU] Do not reset AsyncScore when recording an async mark (PR #213144)

[Sameer Sahasrabuddhe via llvm-commits]

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@@ -677,3 +677,111 @@ epilog:
 
   ret void
 }
+
+; The second mark records only the async operations issued since the first, so it
+; snapshots an empty score and wait.asyncmark(0) emits no vmcnt wait even though
+; it removes both marks.
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ssahasra wrote:

This seems to be describing the behaviour before the fix.

https://github.com/llvm/llvm-project/pull/213144