Only call into the HOsrBuilder if required for OSR.

src/hydrogen.h

 // Copyright 2012 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 1763 matching lines @@
   virtual bool BuildGraph() V8_OVERRIDE;
 
   // Simple accessors.
   BreakAndContinueScope* break_scope() const { return break_scope_; }
   void set_break_scope(BreakAndContinueScope* head) { break_scope_ = head; }
 
   bool inline_bailout() { return inline_bailout_; }
 
   HValue* context() { return environment()->context(); }
 
+  HOsrBuilder* osr() { return osr_; }

[Michael Starzinger, 2013/09/27 13:26:22]

nit: Can be made const.

[mvstanton, 2013/09/27 13:31:43]

Done.

+
   void Bailout(BailoutReason reason);
 
   HBasicBlock* CreateJoin(HBasicBlock* first,
                           HBasicBlock* second,
                           BailoutId join_id);
 
   FunctionState* function_state() const { return function_state_; }
 
   void VisitDeclarations(ZoneList<Declaration*>* declarations);
 
+  // Build a loop entry
+  HBasicBlock* BuildLoopEntry();

[Michael Starzinger, 2013/09/27 13:26:22]

nit: Let's move these two declarations near CreateLoop(), this makes it clear
that they are counterparts to each other.

[mvstanton, 2013/09/27 13:31:43]

Done.

+
+  // Builds a loop entry respectful of OSR requirements
+  HBasicBlock* BuildLoopEntry(IterationStatement* statement);
+
   void* operator new(size_t size, Zone* zone) {
     return zone->New(static_cast<int>(size));
   }
   void operator delete(void* pointer, Zone* zone) { }
   void operator delete(void* pointer) { }
 
   DEFINE_AST_VISITOR_SUBCLASS_MEMBERS();
 
  private:
   // Type of a member function that generates inline code for a native function.
@@ skipping 649 matching lines @@
   }
 
  private:
   HGraphBuilder* builder_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_H_