A new scheme to compute variable orders for binary decision diagrams
نویسندگان
چکیده
In this paper we introduce some new methods using which importance of a variable in a Boolean function can be computed. Such methods can easily be used for computing variable order to construct BDDs. The measures of a variable's importance are based on information-theoretic criteria, and require computation of entropy of a variable, as deened by us, for a given function. We have found that entropy measures can be quite eeective in distinguishing the importance of variables. We also supplement the above algorithm using sophisticated structural analysis. The results show a very encouraging approach to help in the solution of this well known problem.
منابع مشابه
Binary Decision Diagrams and the Multiple Variable Order Problem
Ordered Binary Decision Diagrams (OBDDs) are the rst choice in manipulating and representing Boolean functions in CAD. Since the size of an OBDD heavily depends on the chosen variable order, much eeort is spent in nding good and improving existing variable orders. If these optimizing techniques are used in OBDD applications, one has to cope with OBDDs of diier-ent variable orders very often (e....
متن کاملSolving the Multiple Variable Order Problem for Binary Decision Diagrams by Use of Dynamic Reordering Techniques
Reduced Ordered Binary Decision Diagrams (ROBDDs) gained widespread use in logic design verification, test generation, fault simulation, and logic synthesis [17, 7]. Since the size of an ROBDD heavily depends on the variable order used, there is a strong need to find variable orders that minimize the number of nodes in an ROBDD. In certain applications we have to cope with ROBDDs with different...
متن کاملBasing Decisions on Sentences in Decision Diagrams
The Sentential Decision Diagram (SDD) is a recently proposed representation of Boolean functions, containing Ordered Binary Decision Diagrams (OBDDs) as a distinguished subclass. While OBDDs are characterized by total variable orders, SDDs are characterized by dissections of variable orders, known as vtrees. Despite this generality, SDDs retain a number of properties, such as canonicity and a p...
متن کاملLearning Effective Bdd Variable Orders for Bdd-based Program Analysis
Software reliability and security are in jeopardy. As software has become ubiquitous and its capabilities have become more complex, code quality has been sacrificed in the race for the next ”killer app.” In response, program analysis researchers have mounted a revolution; they have developed new tools and methods, underpinned by traditional compilation techniques, in order to save software from...
متن کاملA New Approach for Finding the various Optimal Variable Ordering to Generate the Binary Decision Diagrams (BDD) of a Computer Communication Network
In this paper we have adopted a new approach for finding the various optimal ordering to generate the binary decision diagrams of a computer communication network. We have shown that these binary decision diagrams are of minimum size and take same time to generate. If two binary decision diagrams have the same size and representing the same Boolean function, then these binary decision diagrams ...
متن کامل