2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS)最新文献

Types Are Internal ∞-Groupoids 类型是内部∞-Groupoids

2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS) Pub Date : 2021-06-29 DOI: 10.1109/LICS52264.2021.9470541

A. Allioux, Eric Finster, Matthieu Sozeau

引用次数: 4

Compositional relational reasoning via operational game semantics 基于操作游戏语义的组合关系推理

2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS) Pub Date : 2021-06-29 DOI: 10.1109/LICS52264.2021.9470524

Guilhem Jaber, A. Murawski

{"title":"Compositional relational reasoning via operational game semantics","authors":"Guilhem Jaber, A. Murawski","doi":"10.1109/LICS52264.2021.9470524","DOIUrl":"https://doi.org/10.1109/LICS52264.2021.9470524","url":null,"abstract":"We show how to use operational game semantics as a guide to develop relational techniques for establishing contextual equivalences with respect to contexts drawn from a hierarchy of four call-by-value higher-order languages: with either general or ground-type references and with either call/cc or no control operator. In game semantics, differences between the contexts can be captured by the absence or presence of the O-visibility and O-bracketing conditions.The proposed technique, which we call Kripke normal-form bisimulations, combines insights from normal-form bisimulation and Kripke logical relations with game semantics. In particular, the role of the heap and the name history is abstracted away using Kripke-style world transition systems. The differences between the four kinds of contexts manifest themselves through simple local conditions that can be shown to correspond to O-visibility and O-bracketing, as applicable.The technique is sound and complete by virtue of correspondence with operational game semantics. Moreover, it sheds a new light on other related developments, such as backtracking and private transitions in Kripke logical relations, which can be related to specific phenomena in game models.","PeriodicalId":174663,"journal":{"name":"2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116954643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Universal Semantics for the Stochastic λ-Calculus 随机λ-微积分的通用语义

2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS) Pub Date : 2021-06-29 DOI: 10.1109/LICS52264.2021.9470747

P. Amorim, D. Kozen, R. Mardare, P. Panangaden, Michael Roberts

引用次数: 5

A distributed operational view of Reversible Prime Event Structures 可逆素数事件结构的分布式操作视图

2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS) Pub Date : 2021-06-29 DOI: 10.1109/LICS52264.2021.9470623

Hernán C. Melgratti, C. A. Mezzina, G. Pinna

{"title":"A distributed operational view of Reversible Prime Event Structures","authors":"Hernán C. Melgratti, C. A. Mezzina, G. Pinna","doi":"10.1109/LICS52264.2021.9470623","DOIUrl":"https://doi.org/10.1109/LICS52264.2021.9470623","url":null,"abstract":"Reversible prime event structures extend the well-known model of prime event structures to represent reversible computational processes. Essentially, they give abstract descriptions of processes capable of undoing computation steps. Since their introduction, event structures have played a pivotal role in connecting operational models (traditionally, Petri nets and process calculi) with denotational ones (algebraic domains). For this reason, there has been a lot of interest in linking different classes of operational models with different kinds of event structures. Hence, it is natural to ask which is the operational counterpart of reversible prime event structures. Such question has been previously addressed for a subclass of reversible prime event structures in which the interplay between causality and reversibility is restricted to the so-called cause-respecting reversible structures. In this paper, we present an operational characterisation of the full-fledged model and show that reversible prime event structures correspond to a subclass of contextual Petri nets, called reversible causal nets. The distinctive feature of reversible causal nets is that causality is recovered from inhibitor arcs instead of the usual overlap between post and presets of transitions. In this way, we are able to operationally explain also out-of-causal order reversibility.","PeriodicalId":174663,"journal":{"name":"2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123934902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

The Undecidability of System F Typability and Type Checking for Reductionists 系统F类型的不可判定性与约化论者的类型检查

2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS) Pub Date : 2021-06-29 DOI: 10.1109/LICS52264.2021.9470520

Andrej Dudenhefner

{"title":"The Undecidability of System F Typability and Type Checking for Reductionists","authors":"Andrej Dudenhefner","doi":"10.1109/LICS52264.2021.9470520","DOIUrl":"https://doi.org/10.1109/LICS52264.2021.9470520","url":null,"abstract":"The undecidability of both typability and type checking for System F (polymorphic lambda-calculus) was established by Wells in the 1990s. For type checking Wells gave an astonishingly simple reduction from semi-unification (first-order unification combined with first-order matching). For typability Wells developed an intricate calculus to control the shape of type assumptions across type derivations via term structure. This calculus of invariant type assumptions allows for a reduction from type checking to typability. Unfortunately, this approach relies on heavy machinery that complicates surveyability of the overall argument.The present work gives comparatively simple, direct reduction from semi-unification to System F typability. The key observation is as follows: in the existential setting of typability, it suffices to consider some specific (but not all, as for invariant type assumptions) type derivations. Additionally, the particular result requires only to consider closed types without nested quantification.The undecidability of type checking is obtained via a folklore reduction from typability.Profiting from its smaller footprint, correctness of the new approach is witnessed by a mechanization in the Coq proof assistant. The mechanization is incorporated into the existing Coq library of undecidability proofs. For free, the library provides constructive, mechanically verified many-one reductions from Turing machine halting to both System F typability and System F type checking.","PeriodicalId":174663,"journal":{"name":"2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS)","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125441930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Minimal Taylor Algebras as a Common Framework for the Three Algebraic Approaches to the CSP 最小泰勒代数作为求解CSP的三种代数方法的共同框架

2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS) Pub Date : 2021-06-29 DOI: 10.1109/LICS52264.2021.9470557

L. Barto, Zarathustra Brady, A. Bulatov, M. Kozik, Dmitriy Zhuk

{"title":"Minimal Taylor Algebras as a Common Framework for the Three Algebraic Approaches to the CSP","authors":"L. Barto, Zarathustra Brady, A. Bulatov, M. Kozik, Dmitriy Zhuk","doi":"10.1109/LICS52264.2021.9470557","DOIUrl":"https://doi.org/10.1109/LICS52264.2021.9470557","url":null,"abstract":"This paper focuses on the algebraic theory underlying the study of the complexity and the algorithms for the Constraint Satisfaction Problem (CSP). We unify, simplify, and extend parts of the three approaches that have been developed to study the CSP over finite templates – absorption theory that was used to characterize CSPs solvable by local consistency methods (JACM’14), and Bulatov’s and Zhuk’s theories that were used for two independent proofs of the CSP Dichotomy Theorem (FOCS’17, JACM’20).As the first contribution we present an elementary theorem about primitive positive definability and use it to obtain the starting points of Bulatov’s and Zhuk’s proofs as corollaries. As the second contribution we propose and initiate a systematic study of minimal Taylor algebras. This class of algebras is broad enough so that it suffices to verify the CSP Dichotomy Theorem on this class only, but still is unusually well behaved. In particular, many concepts from the three approaches coincide in the class, which is in striking contrast with the general setting.We believe that the theory initiated in this paper will eventually result in a simple and more natural proof of the Dichotomy Theorem that employs a simpler and more efficient algorithm, and will help in attacking complexity questions in other CSP-related problems.","PeriodicalId":174663,"journal":{"name":"2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS)","volume":"105 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126662391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Removing Redundant Refusals: Minimal Complete Test Suites for Failure Trace Semantics 删除冗余拒绝:故障跟踪语义的最小完整测试套件

2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS) Pub Date : 2021-06-29 DOI: 10.1109/LICS52264.2021.9470737

Maciej Gazda, R. Hierons

{"title":"Removing Redundant Refusals: Minimal Complete Test Suites for Failure Trace Semantics","authors":"Maciej Gazda, R. Hierons","doi":"10.1109/LICS52264.2021.9470737","DOIUrl":"https://doi.org/10.1109/LICS52264.2021.9470737","url":null,"abstract":"We explore the problem of finding a minimal complete test suite for a refusal trace (or failure trace) semantics. Since complete test suites are typically infinite, we consider the setting with a bound ℓ on the length of refusal traces of interest. A test suite T is thus complete if it is failed by all processes that contain a disallowed refusal trace of length at most ℓ.The proposed approach is based on generating a minimal complete set of forbidden refusal traces. Our solution utilises several interesting insights into refusal trace semantics. In particular, we identify a key class of refusals called fundamental refusals which essentially determine the refusal trace semantics, and the associated fundamental equivalence relation. We then propose a small but not necessarily minimal test suite based on our theory, which can be constructed with a simple algorithm. Subsequently, we provide an enumerative method to remove all redundant traces from our complete test suite, which comes in two variants, depending on whether we wish to retain the highly desirable uniform completeness (guarantee of shortest counterexamples).A related problem is the construction of a characteristic formula of a process P, that is, a formula ΦP such that every process which satisfies ΦP refines P. Our test generation algorithm can be used to construct such a formula using a variant of Hennessy-Milner logic with recursion.","PeriodicalId":174663,"journal":{"name":"2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS)","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125232022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Complexity Lower Bounds from Algorithm Design 算法设计的复杂度下界

2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS) Pub Date : 2021-06-29 DOI: 10.1109/LICS52264.2021.9470522

Richard Ryan Williams

引用次数: 0

Global Optimisation with Constructive Reals 具有建设性现实的全局优化

2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS) Pub Date : 2021-06-29 DOI: 10.1109/LICS52264.2021.9470549

D. Ghica, Todd Waugh Ambridge

引用次数: 1

A Logic for Locally Complete Abstract Interpretations 局部完全抽象解释的逻辑

2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS) Pub Date : 2021-06-29 DOI: 10.1109/LICS52264.2021.9470608

R. Bruni, R. Giacobazzi, R. Gori, Francesco Ranzato

{"title":"A Logic for Locally Complete Abstract Interpretations","authors":"R. Bruni, R. Giacobazzi, R. Gori, Francesco Ranzato","doi":"10.1109/LICS52264.2021.9470608","DOIUrl":"https://doi.org/10.1109/LICS52264.2021.9470608","url":null,"abstract":"We introduce the notion of local completeness in abstract interpretation and define a logic for proving both the correctness and incorrectness of some program specification. Abstract interpretation is extensively used to design sound-by-construction program analyses that over-approximate program behaviours. Completeness of an abstract interpretation A for all possible programs and inputs would be an ideal situation for verifying correctness specifications, because the analysis can be done compositionally and no false alert will arise. Our first result shows that the class of programs whose abstract analysis on A is complete for all inputs has a severely limited expressiveness. A novel notion of local completeness weakens the above requirements by considering only some specific, rather than all, program inputs and thus finds wider applicability. In fact, our main contribution is the design of a proof system, parameterized by an abstraction A, that, for the first time, combines over- and under-approximations of program behaviours. Thanks to local completeness, in a provable triple ⊢A [P ] c [Q], the assertion Q is an under-approximation of the strongest post-condition post[c](P ) such that the abstractions in A of Q and post[c](P ) coincide. This means that Q is never too coarse, namely, under mild assumptions, the abstract interpretation of c does not yield false alerts for the input P iff Q has no alert. Thus, ⊢ A [P ] c [Q] not only ensures that all the alerts raised in Q are true ones, but also that if Q does not raise alerts then c is correct.","PeriodicalId":174663,"journal":{"name":"2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125030958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 18