OBDDs — Ordered Binary Decision Diagrams
In this chapter, we introduce the representation type of ordered binary decision diagrams, called OBDDs for short. Although the underlying model of decision diagrams (or synonymously branching programs) was already studied by Lee and Akers in the 1950s and 1970s, these representations have not been used in serious applications for a long time. In 1986, by adding some ingenious ordering restrictions to these models and providing a sophisticated reduction mechanism, R. Bryant substantially improved the model. Since this time, the improved representation, denoted as OBDD, has invaded nearly all areas of computer-aided VLSI design.
KeywordsVariable Order Reduction Algorithm Switching Function Canonical Representation Reduction Rule
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- The fundamentals of OBDDs, i.e., the model, the reduction idea, efficient algorithms for performing Boolean operations on them, and the equivalence test, go back to Bryant [Bry86, Bry92]. The presented uniqueness theorem follows the presentation of Sieling and Wegener [SW93a, Sie94]. The linear-time reduction algorithm is also due to Sieling and Wegener [SW93b].Google Scholar