Get list of global data stores used in model?

I have a very large model that was given to me. I need to generate a list of all global data stores used in the model. These global data stores are defined using Simulink.Signal objects. But there are MANY more Simulink.Signal objects defined in the base workspace, and only some of them are being used as global data stores. I need to know which ones are being used as global data stores in the model, if possible. Is there a way to do this?