Faster Software Synthesis Using Actor Elimination Techniques for Polychronous Formalism

Abstract

A visual polychronous formalism called Multi-Rate Instantaneous Channel Connected Data Flow (MRICDF)was developed in [1]. In [2], a visual environment called EmCodeSyn was introduced which performs software synthesis from MRICDF models. The synthesis technique replaced clock calculus technique germane to previous polychronous approaches such as SIGNAL with a top down technique based on computing the Prime Implicates (PI) of set of Boolean constraints. This Prime Implicate based method first determines a totally ordered sequence of global synchronization points for all the computation, and then gradually determines if certain computations can synchronize less often. The sequence of global synchronization points are identified by subsequent changes in one of the signals in the system and it is called a master trigger. As opposed to bottom-up clock calculus this method can detect sequential non-implement ability faster. However, the PI computation time increases with the number of variables in the Boolean equations, which in turn increases with the size of the MRICDF network. For faster synthesis, we propose an actor elimination technique that enables reduction of the size of the PI computation problem while preserving the master trigger. Hence it provides a sound and complete abstraction technique for faster determination of sequential implement ability of an MRICDF based model.