Study of trivial compiler equivalence on C++ object-oriented mutation operators

Abstract

Trivial Compiler Equivalence (TCE) has been recently proposed as an effective technique to detect equivalences between programs, where two or more programs are equivalent if the compiler produces the same binary code. Mutation testing can greatly benefit from TCE as a way to reveal some equivalent and duplicate mutants, which traditionally hinder the applicability of the technique. For instance, previous research has shown that about 28% of the mutants generated by traditional mutation operators in C programs can be removed using TCE. However, the effectiveness of TCE has not been assessed with class-level operators, where the percentage of equivalent mutants is known to be higher than when using traditional ones. In this paper, we present an empirical study on the effectiveness of TCE at identifying equivalent and duplicate mutants using C++ class operators. The results show that TCE is helpful to discard equivalent and duplicate mutants: 241 out of 1,987 (12%) in our study, including 189 out of 684 (27.6%) manually-identified equivalent mutants. Large differences were observed among the different case studies, especially in the detection rate of equivalent mutants, which ranged from 4% to 45%.