Affiliation:
1. The Tel-Aviv Academic College, Tel Aviv, Israel
2. Complutense University of Madrid, Madrid, Spain
Abstract
In this paper we study the complexity of the Linear Ranking problem: given a loop, described by linear constraints over a finite set of integer variables, is there a linear ranking function for this loop? While existence of such a function implies termination, this problem is not equivalent to termination. When the variables range over the rationals or reals, the Linear Ranking problem is known to be PTIME decidable. However, when they range over the integers, whether for single-path or multipath loops, the complexity of the Linear Ranking problem has not yet been determined. We show that it is coNP-complete. However, we point out some special cases of importance of PTIME complexity. We also present complete algorithms for synthesizing linear ranking functions, both for the general case and the special PTIME cases.
Publisher
Association for Computing Machinery (ACM)
Subject
Computer Graphics and Computer-Aided Design,Software
Cited by
32 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献
1. On Lexicographic Proof Rules for Probabilistic Termination;Formal Aspects of Computing;2023-06-23
2. Using graph neural networks for program termination;Proceedings of the 30th ACM Joint European Software Engineering Conference and Symposium on the Foundations of Software Engineering;2022-11-07
3. Lifting C semantics for dataflow optimization;Proceedings of the 36th ACM International Conference on Supercomputing;2022-06-28
4. Data-driven loop bound learning for termination analysis;Proceedings of the 44th International Conference on Software Engineering;2022-05-21
5. What’s decidable about linear loops?;Proceedings of the ACM on Programming Languages;2022-01-12