Program Slicing using Functional Networks

Program slicing is a technique for identifying a subprogram from an original program. The subprogram, called a slice, is an executable program which maintains the eeect of the original upon a chosen set of variables at some point within the Control Flow Graph (CFG) of the original. The variable set, CFG node pair is called the slicing criterion. Slices nd applications in debugging, testing, parallelisation, re-use, code measurement and program comprehension. These applications exploit the way in which slicing preserves a projection of the original program's semantics, allowing, in some cases, for considerable syntactic simpliication. The paper introduces an approach to the computation of a slightly more general form of a slice, called a simultaneous slice. A simultaneous slice is constructed with respect to a set of conventional slicing criteria. The approach introduced here uses a functional implementation of a network of communicating processes, each process corresponding to a CFG node and each message corresponding to either a variable name or a node identiier.