--- a/src/share/vm/opto/live.hpp	Fri Mar 08 08:22:18 2013 -0800
+++ b/src/share/vm/opto/live.hpp	Wed Mar 13 10:56:54 2013 +0100
@@ -33,11 +33,35 @@
 #include "opto/regmask.hpp"
 
 class Block;
-class LRG_List;
 class PhaseCFG;
 class VectorSet;
 class IndexSet;
 
+//------------------------------LRG_List---------------------------------------
+// Map Node indices to Live RanGe indices.
+// Array lookup in the optimized case.
+class LRG_List : public ResourceObj {
+  friend class VMStructs;
+  uint _cnt, _max;
+  uint* _lidxs;
+  ReallocMark _nesting;         // assertion check for reallocations
+public:
+  LRG_List( uint max );
+
+  uint lookup( uint nidx ) const {
+    return _lidxs[nidx];
+  }
+  uint operator[] (uint nidx) const { return lookup(nidx); }
+
+  void map( uint nidx, uint lidx ) {
+    assert( nidx < _cnt, "oob" );
+    _lidxs[nidx] = lidx;
+  }
+  void extend( uint nidx, uint lidx );
+
+  uint Size() const { return _cnt; }
+};
+
 //------------------------------PhaseLive--------------------------------------
 // Compute live-in/live-out
 class PhaseLive : public Phase {