def translate( instruction )
      class_name = instruction.class.name.split("::").last
      self.send( "translate_#{class_name}".to_sym , instruction)
    end
def translate( instruction )
      class_name = instruction.class.name.split("::").last
      self.send( "translate_#{class_name}".to_sym , instruction)
    end
translator should translate from register instructio set to it's own (arm eg)
 for each instruction we call the translator with translate_XXX
  with XXX being the class name.
 the result is replaced in the stream