Semantic Correctness of Dependence-based Slicing for Interprocedural, Possibly Nonterminating Programs

Abstract

Existing proofs of correctness for dependence-based slicing methods are limited either to the slicing of intraprocedural programs [2, 39], or the proof is only applicable to a specific slicing method [4, 41]. We contribute a general proof of correctness for dependence-based slicing methods such as Weiser [50, 51], or Binkley et al. [7, 8], for interprocedural, possibly nonterminating programs. The proof uses well-formed weak and strong control closure relations, which are the interprocedural extensions of the generalised weak/strong control closure provided by Danicic et al. [13], capturing various nonterminating-insensitive and nontermination-sensitive control-dependence relations that have been proposed in the literature. Thus, our proof framework is valid for a whole range of existing control-dependence relations. We have provided a definition of semantically correct (SC) slice. We prove that SC slices agree with Weiser slicing, that deterministic SC slices preserve termination, and that nondeterministic SC slices preserve the nondeterministic behavior of the original programs.