Application of Interface Theories to the Separate Compilation of Synchronous Programs

We study the problem of separate compilation, i.e., the generation of modular code, for the discrete time part of block-diagrams formalisms such as Simulink, Modelica, or Scade. Code is modular in that it is generated for a given composite block independently from context (i.e., without knowing in which diagrams the block is to be used) and using minimal information about the internals of the block. Just using off-the-shelf C code generation (e. g., as available in Simulink) does not provide modular code. Separate compilation was solved by Lublinerman et al. for the special case of single-clocked diagrams, in which all signals are updated at a same unique clock. For the same case, Pouzet and Raymond proposed algorithms that scale-up properly to real-size applications. The technique of Lublinerman et al. was extended to some classes of multi-clocked and timed diagrams. We study this problem in its full generality and we show that it can be cast to a special class of controller synthesis problems by relying on recently proposed modal interface theories.