[llvm-branch-commits] [llvm] [AMDGPU] Physical register tracking in GCN trackers. (PR #184275)

[Dhruva Chakrabarti via llvm-branch-commits]

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@@ -320,12 +320,47 @@ class GCNRPTracker {
 
 protected:
   const LiveIntervals &LIS;
+
+  // Virtual register tracking
   LiveRegSet VirtLiveRegs;
   GCNRegPressure CurVirtPressure, MaxVirtPressure;
+
+  // Physical register tracking: Maintain clean separation between virtual and
+  // physical registers. Tracking physical registers can be turned OFF with an
+  // option. Using llvm::LiveRegSet for consistency with the generic tracker.
+  llvm::LiveRegSet PhysLiveRegs;
+  GCNRegPressure CurPhysPressure, MaxPhysPressure;
+
+  // Flag to control whether physical register tracking is active.
+  // Set to true when GCNTrackers are enabled, false otherwise.
+  bool TrackPhysRegs = false;
+
   const MachineInstr *LastTrackedMI = nullptr;
   mutable const MachineRegisterInfo *MRI = nullptr;
 
-  GCNRPTracker(const LiveIntervals &LIS_) : LIS(LIS_) {}
+  GCNRPTracker(const LiveIntervals &LIS, const MachineRegisterInfo &MRI)
+      : LIS(LIS), MRI(&MRI) {
+    setPhysRegTracking();
+    if (TrackPhysRegs)
+      PhysLiveRegs.init(MRI);
+  }
+
+  // Copy constructor - PhysLiveRegs must be initialized then copied.
+  GCNRPTracker(const GCNRPTracker &Other)
+      : LIS(Other.LIS), VirtLiveRegs(Other.VirtLiveRegs),
+        CurVirtPressure(Other.CurVirtPressure),
+        MaxVirtPressure(Other.MaxVirtPressure),
+        CurPhysPressure(Other.CurPhysPressure),
+        MaxPhysPressure(Other.MaxPhysPressure),
+        TrackPhysRegs(Other.TrackPhysRegs), LastTrackedMI(Other.LastTrackedMI),
+        MRI(Other.MRI) {
+    // Initialize PhysLiveRegs with proper universe, then copy contents.
+    if (MRI) {
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dhruvachak wrote:

Changed.

https://github.com/llvm/llvm-project/pull/184275