Only call into the HOsrBuilder if required for OSR.

src/hydrogen-osr.h

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 27 matching lines @@
 // Responsible for building graph parts related to OSR and otherwise
 // setting up the graph to do an OSR compile.
 class HOsrBuilder : public ZoneObject {
  public:
   explicit HOsrBuilder(HOptimizedGraphBuilder* builder)
     : unoptimized_frame_slots_(0),
       builder_(builder),
       osr_entry_(NULL),
       osr_loop_entry_(NULL),
       osr_values_(NULL) { }
+
   // Creates the loop entry block for the given statement, setting up OSR
   // entries as necessary, and sets the current block to the new block.
-  HBasicBlock* BuildPossibleOsrLoopEntry(IterationStatement* statement);
+  HBasicBlock* BuildOsrLoopEntry(IterationStatement* statement);
 
   // Process the hydrogen graph after it has been completed, performing
   // any OSR-specific cleanups or changes.
   void FinishGraph();
 
   // Process the OSR values and phis after initial graph optimization.
   void FinishOsrValues();
 
   // Return the number of slots in the unoptimized frame at the entry to OSR.
   int UnoptimizedFrameSlots() const {
     return unoptimized_frame_slots_;
   }
 
- private:
-  HBasicBlock* BuildLoopEntry();
   bool HasOsrEntryAt(IterationStatement* statement);
 
+ private:
   int unoptimized_frame_slots_;
   HOptimizedGraphBuilder* builder_;
   HBasicBlock* osr_entry_;
   HBasicBlock* osr_loop_entry_;
   ZoneList<HUnknownOSRValue*>* osr_values_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_OSR_H_