Diagnostic Test Generation for Statistical Bug Localization using Evolutionary Computation

Verification is increasingly becoming a bottleneck in the process of designing electronic circuits. While there exists several verification tools that assist in detecting occurrences of design errors, or bugs, there is a lack of solutions for accurately pin-pointing the root causes of these errors. Statistical bug localization has proven to be an approach that scales up to large designs and is widely utilized both in debugging hardware and software. However, the accuracy of localization is highly dependent on the quality of the stimuli. In this paper we formulate diagnostic test set generation as a task for an evolutionary algorithm, and propose dedicated fitness functions that closely correlate with the bug localization capabilities. We perform experiments on the register-transfer level design of the Plasma microprocessor coupling an evolutionary test-pattern generator and a simulator for fitness evaluation. As a result, the diagnostic resolution of the tests is significantly improved.