[llvm] [llvm-exegesis] Add tablegen support for validation counters (PR #76652)

[Aiden Grossman via llvm-commits]

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@@ -28,6 +28,22 @@ class PfmIssueCounter<string resource_name, string counter>
   string ResourceName = resource_name;
 }
 
+class ValidationEvent <int event_number> {
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boomanaiden154 wrote:

Added additional comments on what these are for. Please let me know if they don't clarify things enough.

https://github.com/llvm/llvm-project/pull/76652