Section: New Results

Integration of Polychrony with QGen

Participants : Loïc Besnard, Thierry Gautier, Christophe Junke, Jean-Pierre Talpin.

The FUI project P gave birth to the GGen qualifiable model compiler, developed by Adacore. The tool accepts a discrete subset of Simulink expressed in a language called P and produces C or Ada code.

Our contribution was about providing a semantic bridge between Polychrony and QGen [15]. Our objective was to use Polychrony to compute fined-grained static scheduling of computations and communications for P models based on architectural properties. This work was twofold. First, we defined an alternative unambiguous static block scheduler for QGen, which can compute both partial and total orders based on user preferences. The purpose of this sequencer is to allow QGen to inter-operate with external sequencing tools while providing guarantees about the compatibility of external block execution orders with respect to both QGen's compilation scheme and user expectations. On the other hand, we developed a transformation function from the P language, more precisely, from the System Model subset of P, to the Signal meta-model, SSME. This work is based on a high-level API designed on top of SSME and can be used to transform a subset of Simulink to Signal. We validated our approach with the test suite used by QGen which is composed of over two-hundred small-sized Simulink models. We tested both block sequencing and model transformations. We ran the conversion tool and the set of models used by QGen for its regression tests and successfully converted medium to large models. The P language is capable of representing a useful subset of Simulink. That is why it is an interesting tool to help interpreting Simulink models and possibly architectural properties as executable Signal programs. The programs currently produced with our transformation tool can be compiled by Polychrony and reorganized as clusters of smaller processes.