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

[Valery Pykhtin via llvm-commits]

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@@ -182,34 +192,40 @@ class GCNRPTracker {
 GCNRPTracker::LiveRegSet getLiveRegs(SlotIndex SI, const LiveIntervals &LIS,
                                      const MachineRegisterInfo &MRI);
 
+////////////////////////////////////////////////////////////////////////////////
+// GCNUpwardRPTracker
+
 class GCNUpwardRPTracker : public GCNRPTracker {
 public:
   GCNUpwardRPTracker(const LiveIntervals &LIS_) : GCNRPTracker(LIS_) {}
 
-  // reset tracker and set live register set to the specified value.
-  void reset(const MachineRegisterInfo &MRI_, const LiveRegSet &LiveRegs_);
+  using GCNRPTracker::reset;
 
-  // reset tracker at the specified slot index.
+  /// reset tracker at the specified slot index \p SI.
   void reset(const MachineRegisterInfo &MRI, SlotIndex SI) {
-    reset(MRI, llvm::getLiveRegs(SI, LIS, MRI));
+    GCNRPTracker::reset(MRI, llvm::getLiveRegs(SI, LIS, MRI));
   }
 
-  // reset tracker to the end of the MBB.
+  /// reset tracker to the end of the \p MBB.
   void reset(const MachineBasicBlock &MBB) {
     reset(MBB.getParent()->getRegInfo(),
           LIS.getSlotIndexes()->getMBBEndIdx(&MBB));
   }
 
-  // reset tracker to the point just after MI (in program order).
+  /// reset tracker to the point just after \p MI (in program order).
   void reset(const MachineInstr &MI) {
     reset(MI.getMF()->getRegInfo(), LIS.getInstructionIndex(MI).getDeadSlot());
   }
 
-  // move to the state just before the MI (in program order).
+  /// Move to the state of RP just before the \p MI . If \p UseInternalIterator
+  /// is set, also update the internal iterators. Setting \p UseInternalIterator
+  /// to false allows for an externally managed iterator / program order.
   void recede(const MachineInstr &MI);
 
-  // checks whether the tracker's state after receding MI corresponds
-  // to reported by LIS.
+  void bumpUpwardPressure(const MachineInstr *MI, const SIRegisterInfo *TRI);
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vpykhtin wrote:

Method description would be nice.

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