Reactive Modules

Dr Thomas A. Henzinger
Dept. of Electrical Engineering and Computer Science
UC Berkeley

September 19, 1996
Hogan Room, 531 Cory Hall
4:00-5:00 p.m.


We present a formal model for the design and verification of highly heterogeneous systems. The model represents synchronous and asynchronous components in a uniform framework that supports compositional (assume-guarantee) and hierarchical (stepwise refinement) reasoning. While synchronous models are based on a notion of atomic computation step, and asynchronous models remove that notion by introducing stuttering, our model is based on a flexible notion of what constitutes a computation step: by applying an abstraction operator to a system, arbitrarily many consecutive steps can be collapsed into a single step. The abstraction operator, which may turn an asynchronous system into a synchronous one, allows us to describe systems at various levels of temporal detail. For describing systems at various levels of spatial detail, we use a hiding operator that may turn a synchronous system into an asynchronous one. We illustrate the model with diverse examples from synchronous circuits, asynchronous shared-memory programs, and synchronous message passing.

This is joint work with Rajeev Alur.