Method to input multiple parameters to a MATLAB function block that does not result in a long compile time?

I have a Simulink model that contains a MATLAB function block with a large amount of code. Whenever I modify the content of this function block, the model takes about 5-10 minutes to compile the next time I run it. This function block has a structure parameter; the fields of the struct are defined using a .m file that is run using the InitFcn callback. I have noticed that if I modify the value of any field in the struct (using the .m file, before the simulation begins to run) the model will also take approximately 5-10 minutes to compile on the next run, even if I have not otherwise modified the code within the MATLAB function block. Is there an alternative method to input multiple parameters (the struct fields) into a MATLAB function block that will not result in the large compile times? The struct I am using has many fields (around 100).