[llvm] [AMDGPU] NFC: Provide RPTracker interface for external iterators (PR #93088)

[Matt Arsenault via llvm-commits]

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@@ -343,24 +343,25 @@ void GCNRPTracker::reset(const MachineInstr &MI,
   MaxPressure = CurPressure = getRegPressure(*MRI, LiveRegs);
 }
 
-////////////////////////////////////////////////////////////////////////////////
-// GCNUpwardRPTracker
-
-void GCNUpwardRPTracker::reset(const MachineRegisterInfo &MRI_,
-                               const LiveRegSet &LiveRegs_) {
+void GCNRPTracker::reset(const MachineRegisterInfo &MRI_,
+                         const LiveRegSet &LiveRegs_) {
   MRI = &MRI_;
   LiveRegs = LiveRegs_;
   LastTrackedMI = nullptr;
   MaxPressure = CurPressure = getRegPressure(MRI_, LiveRegs_);
 }
 
-void GCNUpwardRPTracker::recede(const MachineInstr &MI) {
+////////////////////////////////////////////////////////////////////////////////
+// GCNUpwardRPTracker
+
+bool GCNUpwardRPTracker::recede(const MachineInstr &MI, bool ShouldTrackIt) {
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arsenm wrote:

Doxygen comment for what this does? And the parameters and return? Maybe should go on the header, instead of the definition 

https://github.com/llvm/llvm-project/pull/93088