Method of minimizing sum-of-product cases in a heterogeneous data base environment for circuit synthesis

摘要

A method for simplifying Boolean AND-OR logic in a circuit synthesis system. Rules are associated with model instances representing circuit components and contained in a data base. During testing of an antecedent portion of a rule, a benefit value representing a decrease in pins or an improvement in timing is calculated and compared to the value of a "benefit variable", which represents a minimum acceptable benefit that must be gained from application of a rule. If a sufficient benefit will result from application of the rule, the rule is applied. Some rules simplify the circuit and then recursively call themselves. Some rules indicate other model instances in the data base, search the set of rules for rules applicable to that model instance, and apply the rule discovered during the search.