130   // barrier types.  Semantically, it should be thought of as a call to the

   130   // barrier types.  Semantically, it should be thought of as a call to the

   131   // virtual "_work" function below, which must implement the barrier.)

   131   // virtual "_work" function below, which must implement the barrier.)

   132   // First the pre-write versions...

   132   // First the pre-write versions...

   133   template <class T> inline void write_ref_field_pre(T* field, oop new_val);

   133   template <class T> inline void write_ref_field_pre(T* field, oop new_val);

   134 private:

   134 private:

   135   // Keep this private so as to catch violations at build time.

   138   // Keep this private so as to catch violations at build time.

   136   virtual void write_ref_field_pre_work(     void* field, oop new_val) { guarantee(false, "Not needed"); };

   139   virtual void write_ref_field_pre_work(     void* field, oop new_val) { guarantee(false, "Not needed"); };

   137 protected:

   140 protected:

   138   virtual void write_ref_field_pre_work(      oop* field, oop new_val) {};

   141   virtual void write_ref_field_pre_work(      oop* field, oop new_val) {};

   139   virtual void write_ref_field_pre_work(narrowOop* field, oop new_val) {};

   142   virtual void write_ref_field_pre_work(narrowOop* field, oop new_val) {};