Cut-Based Inductive Invariant Computation

This paper presents a new way of computing inductive invariants in sequential designs. The invariants are useful for strengthening inductive proofs in difficult unbounded model checking instances. The proposed computation is scalable and can flexibly trade computational effort for the expressiveness of invariants proved. Experimental results on several benchmark families show that the proposed strengthening proves many hard properties, unsolved by other model checkers. The implementation is publicly available in the synthesis and verification system ABC. Runtimes are reasonable: the hardest problem with 5K primary inputs, 3K registers, and 64K AIG nodes takes 6 minutes.

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