Several efficient compilation techniques have been recently proposed for the generation of sequential (C) code from Esterel programs. Consisting essentially in direct simulation of the reactive features of the language, these techniques need now to be accommodated with traditional issues of Esterel - the definition of formal semantics, the constructive causality, and the design of efficient and correct methods for analysis and optimization.

We address some of these problems by defining a new intermediate model for the representation of Esterel programs. The new representation level preserves much of the initial program structure while making the control flow pattern and the hierarchical state structure explicit. It supports the full Esterel semantics, and it is a good support for efficient analysis, optimization, and code generation algorithms based on static analysis.