'Perform widen operation on the given states, and return a new one.
:param old_state:
:param new_state:
:returns: The widened state, and whether widening has occurred'

@staticmethod
def _widen_states(old_state, new_state):

    l.debug('Widening    state    at    IP    %s', old_state.ip)
    (widened_state, widening_occurred) = old_state.widen(new_state)
    return (widened_state, widening_occurred)
