[llvm] [AMDGPU] Optionally Use GCNRPTrackers during scheduling (PR #93090)

[Valery Pykhtin via llvm-commits]

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@@ -658,6 +747,19 @@ void GCNScheduleDAGMILive::runSchedStages() {
         continue;
       }
 
+      if (GCNTrackers) {
+        GCNDownwardRPTracker *DownwardTracker = S.getDownwardTracker();
+        GCNUpwardRPTracker *UpwardTracker = S.getUpwardTracker();
+        GCNRPTracker::LiveRegSet *RegionLiveIns =
+            &LiveIns[Stage->getRegionIdx()];
+
+        reinterpret_cast<GCNRPTracker *>(DownwardTracker)
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vpykhtin wrote:

This looks criminal. You're forcing a call of a base class constructor for an object of derived type. Why this is needed?

https://github.com/llvm/llvm-project/pull/93090