Static Analysis of a Parallel Logic Language Based on the Blackboard Model

Shared Prolog is a parallel logic language based on the blackboard interpretation of logic programming. In such an interpretation a logic program is seen as a set of rules executed by a set of agents cooperating via a shared working memory called blackboard. A distributed interpreter for Shared Prolog was implemented and described in another paper, where the blackboard was a centralized data structure. In this paper we show how the blackboard can be distributed using some static analysis techniques. The basic idea is to perform an abstract interpretation starting from the Shared Prolog operational semantics to generate data structures which represent possible interactions and links among agents. The resulting data structures are used to reduce the number of run time communication operations in an implementation distributed over a network of workstations.