Apply formal equivalent-mutant filtering to mutation audits

Apply formal equivalence checking in the style of MCY to filter behaviorally equivalent mutants from GateTruth and external RTL-benchmark mutant sets before computing simulation-based mutation scores.

Background

The paper's mutation engine currently reports simulation kill rates without detecting or excluding equivalent mutants. Equivalent mutants can never be killed by a testbench and therefore depress measured mutation scores.

The authors contrast their approach with MCY, which uses formal equivalence checking to discard provably identical mutants, and explicitly identify adopting that approach for GateTruth or audited benchmarks as future work.

References

Applying MCY-style formal mutant-equivalence filtering to our own or an audited benchmark's mutant set, rather than the simulation-only kill rate both currently report, is future work this comparison makes concrete.

— GateTruth: Auditing the Rigor of RTL Design Benchmarks via Mutation Testing  (2608.12635 - Bhadra, 12 Aug 2026) in Section 11, Related Work, mutation-testing discussion

Following standard practice in empirical studies of mutation testing [45], we do not attempt to identify or remove equivalent mutants: reliable detection of equivalent mutants remains an open problem, and manual inspection does not scale to our corpus of 1158 mutants across 20 FUTs.

— Adaptive Strategy Generation for Boundary Value Exploration Beyond Numeric Inputs  (2608.28230 - Akbarova et al., 28 Aug 2026) in Section 4.2, Mutation Analysis, p. 10