Compiling SyncCharts to Synchronous C
SyncCharts are a synchronous Statechart variant to model reactive systems with a precise and deterministic semantics. The simulation and software synthesis for SyncCharts usually involve the compilation into Esterel, which is then further compiled into C code. This can produce efficient code, but has two principal drawbacks: 1) the arbitrary control flow that can be expressed with SyncChart transitions cannot be mapped directly to Esterel, and 2) it is very difficult to map the resulting C code back to the original SyncChart. This paper presents an alternative software synthesis approach for SyncCharts that compiles SyncCharts directly into Synchronous C (SC). The compilation preserves the structure of the original SyncChart, which is advantageous for validation and possibly certification. The compilation assigns thread priorities according to the data dependencies. It optimizes both the number of used threads as well as the maximal used priorities, which corresponds to fast SC code with little memory requirements.