499   virtual Throw*            as_Throw()           { return NULL; }

   499   virtual Throw*            as_Throw()           { return NULL; }

   500   virtual Base*             as_Base()            { return NULL; }

   500   virtual Base*             as_Base()            { return NULL; }

   501   virtual RoundFP*          as_RoundFP()         { return NULL; }

   501   virtual RoundFP*          as_RoundFP()         { return NULL; }

   502   virtual ExceptionObject*  as_ExceptionObject() { return NULL; }

   502   virtual ExceptionObject*  as_ExceptionObject() { return NULL; }

   503   virtual UnsafeOp*         as_UnsafeOp()        { return NULL; }

   503   virtual UnsafeOp*         as_UnsafeOp()        { return NULL; }

   504 

   505 

   505   virtual void visit(InstructionVisitor* v)      = 0;

   506   virtual void visit(InstructionVisitor* v)      = 0;

   506 

   507 

   507   virtual bool can_trap() const                  { return false; }

   508   virtual bool can_trap() const                  { return false; }

   508 

   509