1 files changed, 22 insertions, 3 deletions
diff --git a/include/llvm/CodeGen/MachineScheduler.h b/include/llvm/CodeGen/MachineScheduler.h
index 8590b7a348cf..e327881de13a 100644
--- a/include/llvm/CodeGen/MachineScheduler.h
+++ b/include/llvm/CodeGen/MachineScheduler.h
@@ -26,7 +26,7 @@
 // The default scheduler, ScheduleDAGMILive, builds the DAG and drives list
 // scheduling while updating the instruction stream, register pressure, and live
 // intervals. Most targets don't need to override the DAG builder and list
-// schedulier, but subtargets that require custom scheduling heuristics may
+// scheduler, but subtargets that require custom scheduling heuristics may
 // plugin an alternate MachineSchedStrategy. The strategy is responsible for
 // selecting the highest priority node from the list:
 //
@@ -214,9 +214,20 @@ public:
   /// This has to be enabled in combination with shouldTrackPressure().
   virtual bool shouldTrackLaneMasks() const { return false; }
 
+  // If this method returns true, handling of the scheduling regions
+  // themselves (in case of a scheduling boundary in MBB) will be done
+  // beginning with the topmost region of MBB.
+  virtual bool doMBBSchedRegionsTopDown() const { return false; }
+
   /// Initialize the strategy after building the DAG for a new region.
   virtual void initialize(ScheduleDAGMI *DAG) = 0;
 
+  /// Tell the strategy that MBB is about to be processed.
+  virtual void enterMBB(MachineBasicBlock *MBB) {};
+
+  /// Tell the strategy that current MBB is done.
+  virtual void leaveMBB() {};
+
   /// Notify this strategy that all roots have been released (including those
   /// that depend on EntrySU or ExitSU).
   virtual void registerRoots() {}
@@ -284,6 +295,13 @@ public:
   // Provide a vtable anchor
   ~ScheduleDAGMI() override;
 
+  /// If this method returns true, handling of the scheduling regions
+  /// themselves (in case of a scheduling boundary in MBB) will be done
+  /// beginning with the topmost region of MBB.
+  bool doMBBSchedRegionsTopDown() const override {
+    return SchedImpl->doMBBSchedRegionsTopDown();
+  }
+
   // Returns LiveIntervals instance for use in DAG mutators and such.
   LiveIntervals *getLIS() const { return LIS; }
 
@@ -326,6 +344,9 @@ public:
   /// reorderable instructions.
   void schedule() override;
 
+  void startBlock(MachineBasicBlock *bb) override;
+  void finishBlock() override;
+
   /// Change the position of an instruction within the basic block and update
   /// live ranges and region boundary iterators.
   void moveInstruction(MachineInstr *MI, MachineBasicBlock::iterator InsertPos);
@@ -755,9 +776,7 @@ public:
   /// available instruction, or NULL if there are multiple candidates.
   SUnit *pickOnlyChoice();
 
-#ifndef NDEBUG
   void dumpScheduledState() const;
-#endif
 };
 
 /// Base class for GenericScheduler. This class maintains information about