12. The computer program product according to claim 11 , wherein, in the verification target description conversion instruction, the verification target description is converted into a design description of the narrower term using a design description cross-reference in which correspondences between the design description of the broader term and the design description of the narrower term are described.
11. An assertion description conversion computer program product configured to store program instructions for execution on a computer system to perform: parsing the syntax of a high-level assertion description described by a high-level assertion description language for verification of an inputted design description of a broader term to identify a verification target; searching a description on the verification target in a design description of a broader term; converting the description of the verification target into a design description of a narrower term according to the design description of the narrower term corresponding to the searched description; analyzing verification contents for the verification target described in the high-level assertion description; converting the verification contents into the description format of a low-level assertion description language for verification of a design description of the narrower term; and wherein, in the verification target description conversion instruction, when converting the description of the verification target description into the design description of the narrower term, a description for timing adjustment is added according to synthesis result information at the time when synthesizing the design description of the narrower term according to the design description of the broader term.