Validity-Guided Synthesis of Reactive Systems from Assume-Guarantee Contracts

Automated synthesis of reactive systems from specifications has been a topic of research for decades. Recently, a variety of approaches have been proposed to extend synthesis of reactive systems from proposi- tional specifications towards specifications over rich theories. We propose a novel, completely automated approach to program synthesis which reduces the problem to deciding the validity of a set of forall-exists formulas. In spirit of IC3 / PDR, our problem space is recursively refined by blocking out regions of unsafe states, aiming to discover a fixpoint that describes safe reactions. If such a fixpoint is found, we construct a witness that is directly translated into an implementation. We implemented the algorithm on top of the JKind model checker, and exercised it against contracts written using the Lustre specification language. Experimental results show how the new algorithm outperforms JKinds already existing synthesis procedure based on k-induction and addresses soundness issues in the k-inductive approach with respect to unrealizable results.Comment: 18 pages, 5 figures, 2 table

Program Synthesis using Natural Language

Interacting with computers is a ubiquitous activity for millions of people. Repetitive or specialized tasks often require creation of small, often one-off, programs. End-users struggle with learning and using the myriad of domain-specific languages (DSLs) to effectively accomplish these tasks. We present a general framework for constructing program synthesizers that take natural language (NL) inputs and produce expressions in a target DSL. The framework takes as input a DSL definition and training data consisting of NL/DSL pairs. From these it constructs a synthesizer by learning optimal weights and classifiers (using NLP features) that rank the outputs of a keyword-programming based translation. We applied our framework to three domains: repetitive text editing, an intelligent tutoring system, and flight information queries. On 1200+ English descriptions, the respective synthesizers rank the desired program as the top-1 and top-3 for 80% and 90% descriptions respectively

Автоматизоване проектування програм для розв’язання задачі метеорологічного прогнозування

Розроблено засіб автоматизованого конструювання паралельного коду для середовища OpenMP на основі високорівневих алгебро-алгоритмічних специфікацій. Застосування засобу демонструється на прикладі задачі моделювання циркуляції атмосфери, що представлений як сервіс у складі Інтернет-порталу з надання послуг метеопрогнозу. Здійснена генерація програмного коду та наведено результати експерименту з виконання розробленої паралельної програми прогнозування на мультипроцесорній платформі.Разработано средство автоматизированного конструирования параллельного кода для среды OpenMP на основе высокоуровневых алгебро-алгоритмических спецификаций. Применение средства демонстрируется на примере задачи моделирования циркуляции атмосферы, представленном как сервис в составе Интернетпортала для предоставления услуг метеопрогноза. Осуществлена генерация программного кода и приведены результаты эксперимента по выполнению разработанной параллельной программы прогнозирования на мультипроцессорной платформе.The facilities for automated design of parallel code for OpenMP environment on the basis of highlevel algebra-algorithmic specifications are developed. The application of the facilities is illustrated on an example of a problem of atmosphere circulation modeling, which is represented as a service, belonging to the Internet-portal for providing meteorological forecasting services. The generation of program code was implemented and the results of the conducted experiment, which consisted in execution of the developed parallel weather forecasting program on a multiprocessor platform, are given