'Merge two abstract states.
:param VariableRecoveryState other: The other abstract state to merge.
:return:                            The merged abstract state.
:rtype:                             VariableRecoveryState'

def merge(self, other, successor=None):

    def _make_phi(*variables):
        return self._make_phi(successor, *variables)
    merged_stack_region = self.stack_region.copy().merge(other.stack_region, make_phi_func=_make_phi)
    merged_register_region = self.register_region.copy().merge(other.register_region, make_phi_func=_make_phi)
    state = VariableRecoveryFastState(self.variable_manager, self.arch, self.function, stack_region=merged_stack_region, register_region=merged_register_region, processor_state=self.processor_state.copy().merge(other.processor_state), make_phi=self._make_phi)
    return state
