Predictable space behaviour in FSM-Hume

The purpose of the Hume language design is to explore the expressibility/decidability spectrum in resource-constrained systems, such as real-time embedded or control systems. It is unusual in being based on a combination of ?-calculus and finite state machine notions, rather than the more usual prepositional logic, or flat finite-state-machine models. It provides a number of high level features including polymorphic types, arbitrary but sized user-defined data structures and automatic memory management, whilst seeking to guarantee strong space/time behaviour and maintaining overall determinacy. A key issue is predictable space behaviour. This paper describes a simple model for calculating stack and heap costs in FSM-Hume, a limited subset of full Hume. This cost model is evaluated against an example taken from the research literature: a simple mine drainage control system. Empirical results suggest that our model is a good predictor of stack and heap usage, and that this can lead to good bounded memory utilisation. © Springer-Verlag Berlin Heidelberg 2003.