You cannot compile a .m simulink model that uses sim(). Here is the list of MATLAB Functions that cannot be compiled
You can use ert_shrlib.tlc if you have the Embedded Coder product to generate generic DLLs from your Simulink model. The relevant documentation is here: Shared Object Libraries This will compile simulink model to a dll and you can try calling the dll fro .m file and add references to it while compiling.
This is not a tested or well known method but you can give it a try.
