1. A computer program product embodied in a non-transitory computer readable medium, which when executed by a processor, causes the processor to perform design analysis, the computer program product comprising instructions that when executed cause the processor to: apply a set of inputs to a first representation and the set of inputs to a second representation for a semiconductor design wherein the semiconductor design is for fabrication in a semiconductor process; compare outputs of the first representation and outputs of the second representation, based on the set of inputs that were applied, to look for mismatch between the outputs of the first representation and the outputs of the second representation; evaluate in response to detecting a mismatch, a starting point for the first representation to determine whether the starting point for the first representation is reachable; and generate a generalized constraint for the starting point for the second representation, if the starting point for the second representation is not reachable, wherein the generalized constraint is based on an invariant that holds in every reachable state of the semiconductor design.