[llvm] MachineScheduler: Improve instruction clustering (PR #137784)

[via llvm-commits]

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@@ -2093,6 +2090,21 @@ void BaseMemOpClusterMutation::clusterNeighboringMemOps(
                       << ", Curr cluster bytes: " << CurrentClusterBytes
                       << "\n");
   }
+
+  // Add cluster group information.
+  // Iterate over all of the equivalence sets.
+  auto &AllClusters = DAG->getClusters();
+  for (auto &I : Clusters) {
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ruiling wrote:

It seems like the actual type is `EquivalenceClasses<SUnit *>::ECValue *`.But the type is a private class type and cannot be used outside of its parent. Maybe we need to change the ECValue to be **public**?

https://github.com/llvm/llvm-project/pull/137784