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

[Valery Pykhtin via llvm-commits]

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@@ -687,20 +744,45 @@ void GCNScheduleDAGMILive::computeBlockPressure(unsigned RegionIdx,
 }
 
 DenseMap<MachineInstr *, GCNRPTracker::LiveRegSet>
-GCNScheduleDAGMILive::getBBLiveInMap() const {
+GCNScheduleDAGMILive::getRegionLiveInMap() const {
   assert(!Regions.empty());
-  std::vector<MachineInstr *> BBStarters;
-  BBStarters.reserve(Regions.size());
+  std::vector<MachineInstr *> RegionFirstMIs;
+  RegionFirstMIs.reserve(Regions.size());
   auto I = Regions.rbegin(), E = Regions.rend();
   auto *BB = I->first->getParent();
   do {
     auto *MI = &*skipDebugInstructionsForward(I->first, I->second);
-    BBStarters.push_back(MI);
+    RegionFirstMIs.push_back(MI);
     do {
       ++I;
     } while (I != E && I->first->getParent() == BB);
   } while (I != E);
-  return getLiveRegMap(BBStarters, false /*After*/, *LIS);
+  return getLiveRegMap(RegionFirstMIs, /*After=*/false, *LIS);
+}
+
+DenseMap<MachineInstr *, GCNRPTracker::LiveRegSet>
+GCNScheduleDAGMILive::getRegionLiveOutMap() const {
+  assert(!Regions.empty());
+  std::vector<MachineInstr *> RegionLastMIs;
+  RegionLastMIs.reserve(Regions.size());
+  for (auto &[RegionBegin, RegionEnd] : reverse(Regions))
+    RegionLastMIs.push_back(getLastMIForRegion(RegionBegin, RegionEnd));
+
+  return getLiveRegMap(RegionLastMIs, /*After=*/true, *LIS);
+}
+
+void RegionPressureMap::buildLiveRegMap() {
+  IdxToInstruction.clear();
+
+  BBLiveRegMap =
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vpykhtin wrote:

should we rename this to RgnLiveRegMap?

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