CSC-Aware STG Decomposition

18th UK Asynchronous Forum, 2006

Previous attempts to decompose STGs (and to synthesise the resulting components, instead of synthesising the original STG directly) turned out to be quite successful regarding the runtime. While this was even the case for a first naive implementation, recent improvements of our decomposition algorithm improved the runtime even more. Unfortunately, decomposition also reduces the solution space for synthesis, sometimes in a way that the resulting components could not be synthesised due to irreducible CSC conflicts. But even when the components are synthesisable it is often needed to solve CSC with additional signals, though increasing area; this can also happen if the original STG has CSC initially. In this paper, our latest decomposition algorithm is described, which tackles this problem by reducing the components only to the point where CSC is satisfied by signals already belonging to the circuit instead of solving CSC with new signals. This is an advantage for STGs which satisfy CSC initially; if this is not the case, CSC has to be solved for the STG as well as for the final components.