How to use a Fuzzy Interference System as a global variable in simulink

In a simulink model, I have an embedded function, which is run very frequently, in which I define a Fuzzy Interference System using "readfis" function. I found this function is very time-consuming, and most running time of the model is due to this function. I could not use Data Store Memory (DSM) to globalize this variable, because its data type is unknown for DSM. Which other options do I have, or how can I use DSM for such a data type.