Eliminating unreachable coverage to speed closure
Formal verification is a very powerful addition to any chip project, providing proofs and a degree of completeness that simulation cannot match. While formal verification may reduce the amount of simulation needed, it cannot displace simulation entirely. Some aspects of design behavior, including hardware-software co-verification, require simulation or emulation.
Given the modern chip projects rely on a mix of simulation and formal, the verification team needs to be able to plan for using both approaches and to assess the impact of their work in a common top-level views of verification progress. The OneSpin PortableCoverage platform provides these capabilities.
The Coverage Closure Accelerator App formally identifies unreachable coverage points and provides them to the simulator. This can save enormous amounts of simulation time, since project teams don’t have to waste time trying to hit coverage points that can never be reached. The formal nature of the reachability analysis assures that there are no false negatives; coverage flagged is truly unreachable by any simulation test. Unreachable coverage points also artificially lower coverage metrics; when these are removed from consideration a more accurate view of verification progress results: (#hit)/(#all - #unreachable) rather than (#hit)/(#all).
Unlike closed, single-vendor ABV flows, OneSpin’s Coverage Closure Accelerator App is open and supports coverage databases and simulators from all major vendors.