LOGICAL FUNCTION DECOMPOSITION METHOD AND DEVICE FOR LOGICAL DESIGN AND RECORDING MEDIUM RECORDING LOGICAL FUNCTION DECOMPOSITION PROGRAM FOR LOGICAL DESIGN

摘要

PROBLEM TO BE SOLVED: To effectively decompose an incompletely designated logical function into two logical functions of with small number of inputs by securing from an initial solution such a decomposition that has a minimum total of variables included in each variable set. ;SOLUTION: When a logical function is decomposed in a logical design mode where a given logical function (f) is decomposed into an exclusive OR (XOR) which is shown in an expression, an initial solution generation part for XOR decomposition generates initial solution g₁ and g₂, i.e., temporary solutions from the inputted function (f). These generated solutions are inputted to a branch limiting method control part, and an optimum XOR solution is acquired based on a branch limiting method. In those operations, it's required if possible to eliminate dependence of a certain variable x_i from a certain intermediate solution g₁ (g₂). Thereby, dependence of the variable x_i is eliminated if possible from the solution g₁ at dependent variable elimination part for XOR decomposition when a sum set No Depend of variables which are already and specifically eliminated from solution g₁ and g₂ is given.;COPYRIGHT: (C)1999,JPO