A Quantum Variational Approach to Debugging Combinational Logic Circuits

The application of a quantum approach to combinational logic circuit debugging for future use in Very Large-Scale Integration system design is presented. Although previous work in this area has sped up debugging solutions through the use of satisfiability solvers, the solutions remain classically intractable for large systems. Additionally, whilst many quantum algorithms have shown promise in solving classically intractable problems, there have been few domain-specific implementations, particularly where hard and soft constraints exist and multiple solutions are required. A Quantum Alternating Operator Ansatz is applied to a reduction of the satisfiability problem into a maximum independent set problem. While the Quantum Alternating Operator Ansatz approach constrains the optimization to feasible solutions, the resulting ansatz is both too large for current Noisy Intermediate-Scale Quantum devices and to simulate using a Hamiltonian formulation with gradient-based optimisers. Therefore, a circuit driven simulation is preferred. A small example of a debugging problem is simulated using the aforementioned approach.