[llvm] [llvm-mca][FeatureRequest] Itimeline graph, note source of delay for each instruction (PR #136423)

[via llvm-commits]

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@@ -99,6 +99,10 @@ void TimelineView::onEvent(const HWInstructionEvent &Event) {
     if (Timeline[Index].CycleDispatched == -1)
       Timeline[Index].CycleDispatched = static_cast<int>(CurrentCycle);
     break;
+  case HWInstructionEvent::Pending: {
+    Timeline[Index].CyclePending = CurrentCycle;
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sommersun wrote:

no use.l will remove it.

https://github.com/llvm/llvm-project/pull/136423