Diversity has been regarded as a desirable property of redundant instances, since it allows circuits to behave differently in front of a given fault. However, while qualitatively diversity is a well-understood concept, usable efficient metrics do not exist to quantify diversity in the context of safety-related systems. In this paper we cover this gap by proposing DIMP, a low-cost diversity metric based on analyzing the paths of the redundant circuits. We relate it to the particular case of automotive microcontrollers implementing lockstep cores and show that it can be successfully used providing relevant information for addressing common cause faults.

This work has been partially supported by the Spanish Ministry of Economy and Competitiveness (MINECO) under grant TIN2015-65316-P and the HiPEAC Network of Excellence. Jaume Abella has been partially supported by the MINECO under Ramon y Cajal postdoctoral fellowship number RYC-2013-14717. Carles Hernández is jointly funded by the MINECO and FEDER funds through grant TIN2014-60404-JIN.