Operation net system: A formal design representation model for high-level synthesis of asynchronous systems based on transformations

This paper proposes a formal design representation model, called Operation Net System, for high-level synthesis of asynchronous systems which is based on transformational approaches. Operation Net System consists of Operation Net, which is based on hierarchical timed Petri nets, and a module graph to unify the description of control and data parts of an asynchronous system. It is used as an intermediate design representation during transformations. Several semantic-preserving basic transformations are defined and used to successively transform an initial design representation into an optimized implementation satisfying designer's requirements. The hierarchical concept of Operation Net reduces the complexity of net operations such as finding the relation of two operations by hiding sub-hierarchical blocks. The selection of the basic transformations is guided by an exploration strategy which performs operation scheduling, resource allocation, and module binding simultaneously. To deal with the complexity of the exploration, we use an iterative algorithm such as Tabu search. This integration of high-level synthesis sub-tasks enables designers to get a better chance to reach a globally optimized solution.