MSTC: A Method for Identifying Overconstraints during Hierarchical Compaction

Hierarchical compaction requires that a system of linear equations be solved, usually via linear programming (LP) techniques. In the presence of overconstraints, LP techniques provide inadequate information to locate the cause of these overconstraints. A new graph theoretical method capable of identifying overconstraints and providing meaningful feedback to the user is described. The method also considerably reduces the number of equations to be solved by LP, making compaction of very large layouts possible.