Efficient Cross-Level Processor Verification using Coverage-guided Fuzzing

In this paper, we propose a novel simulation-based cross-level approach for processor verification at the Register-Transfer Level (RTL). We leverage state-of-the-art coverage-guided fuzzing techniques from the software domain to generate processor-level input stimuli. An Instruction Set Simulator (ISS) is utilized as a reference model for the RTL processor under test in an efficient co-simulation setting. To further boost the fuzzing effectiveness, we devised custom mutation procedures tailored for the processor verification domain. Our experiments using the popular open-source RISC-V based VexRiscv processor demonstrate the effectiveness of our approach in finding intricate bugs at the processor level.