Slicing Programs in the Presence of Errors

. Program slicing is a technique by which statements are deleted from a program in such a way as to preserve a projection of the original program's semantics. It is shown that slicing algorithms based upon traditional defined and referenced variable sets do not preserve a projection of strict semantics with respect to computations which cause errors. Rather, these approaches preserve a projection of the program's semantics which is lazy with respect to errors. A modified version of defined and referenced variable sets is introduced, which provides the freedom to choose the form of semantics to be preserved. 1. Introduction A slice is constructed with respect to a slicing criterion (V; n), where V is a set of variable identifiers and n is a point of interest within the program 1 . Definition 1 provides an informal definition of a program slice. Definition 1. (Slice) Given a program p and a slicing criterion (V; n), a program slice p 0 is created by deleting statements from p. Any ..