Add SplitKit API to query and select the current interval being worked on.

[oota-llvm.git] / lib / CodeGen / SplitKit.h

diff --git a/lib/CodeGen/SplitKit.h b/lib/CodeGen/SplitKit.h
index 20ac8a1fdc5d70b05773be88e4fe3865245ce791..fab56f70d9bac15a3364c78cc0f2350f79fd9674 100644 (file)
--- a/lib/CodeGen/SplitKit.h
+++ b/lib/CodeGen/SplitKit.h
@@ -89,7 +89,10 @@ private:
   SmallVector<BlockInfo, 8> UseBlocks;
 
   /// ThroughBlocks - Block numbers where CurLI is live through without uses.
-  SmallVector<unsigned, 8> ThroughBlocks;
+  BitVector ThroughBlocks;
+
+  /// NumThroughBlocks - Number of live-through blocks.
+  unsigned NumThroughBlocks;
 
   SlotIndex computeLastSplitPoint(unsigned Num);
 
@@ -135,9 +138,11 @@ public:
   /// where CurLI has uses.
   ArrayRef<BlockInfo> getUseBlocks() { return UseBlocks; }
 
-  /// getThroughBlocks - Return an array of block numbers where CurLI is live
-  /// through without uses.
-  ArrayRef<unsigned> getThroughBlocks() { return ThroughBlocks; }
+  /// getNumThroughBlocks - Return the number of through blocks.
+  unsigned getNumThroughBlocks() const { return NumThroughBlocks; }
+
+  /// isThroughBlock - Return true if CurLI is live through MBB without uses.
+  bool isThroughBlock(unsigned MBB) const { return ThroughBlocks.test(MBB); }
 
   typedef SmallPtrSet<const MachineBasicBlock*, 16> BlockPtrSet;
 
@@ -278,7 +283,15 @@ public:
   void reset(LiveRangeEdit&);
 
   /// Create a new virtual register and live interval.
-  void openIntv();
+  /// Return the interval index, starting from 1. Interval index 0 is the
+  /// implicit complement interval.
+  unsigned openIntv();
+
+  /// currentIntv - Return the current interval index.
+  unsigned currentIntv() const { return OpenIdx; }
+
+  /// selectIntv - Select a previously opened interval index.
+  void selectIntv(unsigned Idx);
 
   /// enterIntvBefore - Enter the open interval before the instruction at Idx.
   /// If the parent interval is not live before Idx, a COPY is not inserted.