[llvm-branch-commits] [llvm] [AMDGPU][NewInsertWaitcnt] Event Tracker (2/2) (PR #232344)

[Sameer Sahasrabuddhe via llvm-branch-commits]

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@@ -63,27 +68,71 @@ struct CounterInfo {
 
 /// Represents a record within the \ref EventTracker's timeline
 /// for one \ref InstCounterType. A record is a pair of \ref MachineInstr
-/// and \ref SingleHWEvent.
+/// and \ref SingleHWEvent with a height in the timeline.
+///
+/// The height is a conservative minimum estimate of *when* the event it
+/// represents occurred. It is used to emit a wait instruction that ensures the
+/// event has completed (e.g. Height = 2 means "wait 2" on the counter ensures
+/// completion of the event across all control-flow paths).
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ssahasra wrote:

So the height is the minimum estimate of how many events were added after this one?

https://github.com/llvm/llvm-project/pull/232344