Hardware-Based Mutation

Hardware-Based Mutation is a technique described in the Instiller RTL fuzzing work. In the cited paper, it appears as part of “hardware-based seed selection and mutation strategies” intended to improve fuzzing performance in RTL fuzzing by using hardware-related heuristics and mutation operations.^[1]

Context

Instiller is presented as an RTL fuzzer for CPU-oriented hardware verification. The paper motivates RTL fuzzing by noting that hardware bugs must be detected before deployment, and that previous CPU fuzzing approaches face issues such as growing RTL input-instruction length and ineffective longer inputs.^[2]

Technique role

Within Instiller, Hardware-Based Mutation is one of several proposed techniques. The paper lists three major technique areas: input-instruction distillation based on a variant of ant colony optimization, handling multiple interruptions and exceptions with priorities, and hardware-based seed selection and mutation strategies.^[3]

The available evidence does not provide the detailed mutation operators themselves, but it does state the design intent: hardware-related heuristics and mutation operations are used to improve fuzzing performance in the RTL-fuzzing setting.^[1]

Reported system-level results

The Instiller paper reports that the prototype outperforms prior work in experiments on real-world target CPU cores, including 29.4% more coverage than DiFuzzRTL and 17.0% more detected mismatches. These results are reported for Instiller as a whole, not isolated specifically to Hardware-Based Mutation.^[4]

^[1]: Hardware-Based Mutation description. ^[2]: Instiller RTL fuzzing context. ^[3]: Instiller contribution list. ^[4]: Instiller reported evaluation results.