Section: New Software and Platforms

The Polychrony toolset

Participants : Loïc Besnard, Thierry Gautier, Paul Le Guernic, Jean-Pierre Talpin.

The Polychrony toolset is an Open Source development environment for critical/embedded systems. It is based on Signal, a real-time polychronous dataflow language. It provides a unified model-driven environment to perform design exploration by using top-down and bottom-up design methodologies formally supported by design model transformations from specification to implementation and from synchrony to asynchrony. It can be included in heterogeneous design systems with various input formalisms and output languages.

Figure 2. The Polychrony toolset high-level architecture

The Polychrony toolset provides a formal framework to:

  • validate a design at different levels, by the way of formal verification and/or simulation,

  • refine descriptions in a top-down approach,

  • abstract properties needed for black-box composition,

  • assemble heterogeneous predefined components (bottom-up with COTS),

  • generate executable code for various architectures.

The Polychrony toolset contains three main components and an experimental interface to GNU Compiler Collection (GCC):

  • The Signal toolbox, a batch compiler for the Signal language, and a structured API that provides a set of program transformations. Itcan be installed without other components and is distributed under GPL V2 license.

  • The Signal GUI, a Graphical User Interface to the Signal toolbox (editor + interactive access to compiling functionalities). It can be used either as a specific tool or as a graphical view under Eclipse. In 2015, it has been transformed and restructured, in order to get a more up-to-date interface allowing multi-window manipulation of programs. It is distributed under GPL V2 license.

  • The SSME platform, a front-end to the Signal toolbox in the Eclipse environment. It is distributed under EPL license.

  • GCCst, a back-end to GCC that generates Signal programs (not yet available for download).

The Polychrony toolset also provides a large library of Signal programs and examples, user documentations and developer-oriented implementation documents, and facilities to generate new versions.

The Polychrony toolset can be freely downloaded on the following web sites:

  • The Polychrony toolset public web site: http://polychrony.inria.fr/ . This site, intended for users and for developers, contains downloadable executable and source versions of the software for differents platforms, user documentation, examples, libraries, scientific publications and implementation documentation. In particular, this is the site for the open-source distribution of Polychrony.

  • The Inria GForge: https://gforge.inria.fr . This site, intended for internal developers, contains the whole sources of the environment and their documentation.

As part of its open-source release, the Polychrony toolset not only comprises source code libraries but also an important corpus of structured documentation, whose aim is not only to document each functionality and service, but also to help a potential developer to package a subset of these functionalities and services, and adapt them to developing a new application-specific tool: a new language front-end, a new back-end compiler. This multi-scale, multi-purpose documentation aims to provide different views of the software, from a high-level structural view to low-level descriptions of basic modules. It supports a distribution of the software “by apartment” (a functionality or a set of functionalities) intended for developers who would only be interested by part of the services of the toolset.