SCGSequentially Constructive Graph Representation

Fundamental Concepts

Core Transformations

Synchronous Program Classes Sequentially Constructive MoC

Contact:Prof. Dr. Reinhard von Hanxleden,Christian Motika, Steven Smyth Department of Computer ScienceChristian-Albrechts-Universität zu KielOlshausenstr. 40 24098 Kiel, GermanyPhone: +49 (0) 431 880-7282 /-7526Fax: +49 (0) 431 880-7615rvh@,cmot@,ssm@informatik.uni-kiel.dewww.informatik.uni-kiel.de/rtsys

Christian-Albrechts-Universität zu Kiel

Faculty of Engineering

Department of Computer Science

External Funding: Further Information:http://www.informatik.uni-kiel.de/rtsys/kieler[1] Reinhard von Hanxleden and Michael Mendler and Joaquin Aguado and Björn Duderstadt and Insa Fuhrmann and Christian Motika and Stephen Mercer and Owen O’Brien. Sequentially Constructive Concurrency—A Conservative Extension of the Synchronous Model of Computation. In Proceedings of the Design, Automation and Test in Europe Conference (DATE’13), Grenoble, France, 2013. IEEE.

[2] Reinhard von Hanxleden. SyncCharts in C—a proposal for light-weight, deterministic concurrency. In Proceedingsof the International Conference on Embedded Software (EMSOFT’09), Grenoble, France, October 2009.

[3] Christian Motika and Reinhard von Hanxleden and Mirko Heinold. Programming Deterministice Reactive Systems with Synchronous Java (Invited Paper). In Proceedings of the 9th Workshop on Software Technologies for Future Embedded and Ubiquitous Systems (SEUS 2013), IEEE Proceedings, Paderborn, Germany, 17/18 2013.

[4] Reinhard von Hanxleden and Edward A. Lee and Christian Motika and Hauke Fuhrmann. Multi-View Modeling and Pragmatics in 2020 - Position Paper on Designing Complex Cyber-Physical Systems. In Proceedings of the 17th International Monterey Workshop on Development, Operation and Management of Large-Scale Complex IT Systems, LNCS, volume 7539 of , Oxford, UK, 19-21 2012.

HW + SW Compiler Stack

Poster presented at 10th Biennial Ptolemy Miniconference (PTCONF'13), Berkeley, CA, November 2013, © Christian Motika, Steven Smyth, Reinhard v. Hanxleden, Michael Mendler 2013

SCCharts Sequentially Constructive Charts

SCCharts – Sequential Constructive Charts for Safety-Critical Systems

Rejected in SCCharts and SyncChartsbecause of dependency cycle

Extended SCCharts

SCG-normalized SCChart

● Time divided into discrete ticks● Computations take no time● Holds for most synchronous languages, e.g., Lustre, Esterel, SCADE, SyncCharts, SCCharts

Accepted in SCCharts but rejected in SyncCharts

Synchrony Hypothesis [G. Luettgen, 2001]

Representation as SCG

● Natural sequencing prescribes deterministic scheduling● “stmt1; stmt2”, “trigger/effect”● Novelty: Prescriptive (not descriptive like Esterel/SyncCharts)

● Only concurrent data dependencies matter ● Novelty: Sequential data dependencies do not lead to rejection

● Concurrent initialize/update/read scheduling:1. Absolute writes (“x = false”)2. Relative writes (“x = x | true)”3. Reads (“y = x”)

● Novelty: Distinguish between relative and absolute writes

SC MoC in a Nutshell

Synchrony Hypothesis

Extended SCCharts with Signals

Absolute Write − Read Dependency

Absolute Write − Relative Write Dependency

Write − Write Dependency (reject)

Relative Write − Read Dependency

Core SCCharts

SCG-normalized Core SCCharts

SCG Representation& Dependency-Analysis

Basic Blocks Sequentialized SCG

SW (C Program)

Pause

Dependency Types

Textual SCL

HW (SSA/Netlist)

Core SCCharts with During Actions Core SCCharts only (optimized)

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Prof. Dr. Michael MendlerDepartment of Computer ScienceUniversität BambergAn der Weberei 596047 Bamberg, GermanyPhone: +49 (0) 951 863-2828Fax: +49 (0) 951 863-1200michael.mendler@uni-bamberg.dewww.gdi.uni-bamberg.de/personnel/mendler

Core SCCharts only

Action expansion

Alternative Action expansion

Optimization

Signal expansion

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6b

Conditional

Assignment

6a

German Research Foundation,PRETSY Projectdfg.depretsy.org

National Instrumentsni.com