Translation Templates to Support Strategy Development in PVS

In presenting specifications and specification properties to a theorem prover, there is a tension between convenience for the user and convenience for the theorem prover. A choice of specification formulation that is most natural to a user may not be the ideal formulation for reasoning about that specification in a theorem prover. However, when the theorem prover is being integrated into a system development framework, a desirable goal of the integration is to make use of the theorem prover as easy as possible for the user. In such a context, it is possible to have the best of both worlds: specifications that are natural for a system developer to write in the language of the development framework, and representations of these specifications that are well matched to the reasoning techniques provided in the prover. In a tactic-based prover, these reasoning techniques include the use of tactics (or strategies) that can rely on certain structural elements in the theorem prover’s representation of specifications. This paper illustrates how translation techniques used in integrating PVS into the TIOA (Timed Input/Output Automata) system development framework produce PVS specifications structured to support development of PVS strategies that implement reasoning steps appropriate for proving TIOA specification properties.