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Denotational fixed-point semantics for constructive scheduling of synchronous concurrency

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Abstract

The synchronous model of concurrent computation (SMoCC) is well established for programming languages in the domain of safety-critical reactive and embedded systems. Translated into mainstream C/Java programming, the SMoCC corresponds to a cyclic execution model in which concurrent threads are synchronised on a logical clock that cuts system computation into a sequence of macro-steps. A causality analysis verifies the existence of a schedule on memory accesses to ensure each macro-step is deadlock-free and determinate. We introduce an abstract semantic domain \(I(\mathbb {D}, \mathbb {P})\) and an associated denotational fixed-point semantics for reasoning about concurrent and sequential variable accesses within a synchronous cycle-based model of computation. We use this domain for a new and extended behavioural definition of Berry’s causality analysis in terms of approximation intervals. The domain \(I(\mathbb {D}, \mathbb {P})\) extends the domain \(I(\mathbb {D})\) from our previous work and fixes a mistake in the treatment of initialisations. Based on this fixed-point semantics we propose the notion of Input Berry-constructiveness (IBC) for synchronous programs. This new IBC class lies properly between strong (SBC) and normal Berry-constructiveness (BC) defined in previous work. SBC and BC are two ways to interpret the standard constructive semantics of synchronous programming, as exemplified by imperative SMoCC languages such as Esterel or Quartz. SBC is often too restrictive as it requires all variables to be initialised by the program. BC can be too permissive because it initialises all variables to a fixed value, by default. Where the initialisation happens through the memory, e.g., when carrying values from one synchronous tick to the next, then IBC is more appropriate. IBC links two levels of execution, the macro-step level and the micro-step level. We prove that the denotational fixed-point analysis for IBC, and hence Berry’s causality analysis, is sound with respect to operational micro-level scheduling. The denotational model can thus be viewed as a compositional presentation of a synchronous scheduling strategy that ensures reactiveness and determinacy for imperative concurrent programming.

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Notes

  1. This is sometimes referred to as the ‘LAGS’ model and not to be confused with the well-known but orthogonal ‘GALS’ model which features globally asynchronous and locally synchronous computations.

  2. There is an informal sketch of a micro-step semantics in [12], Sect. 4.3] which is not developed further or formally related with the fixed-point semantics for macro-steps.

  3. This stands here for “pure Synchronous Constructive Language” indicating not only that signal variables in pSCL carry Boolean status but also that pSCL is a minimalistic version of control-flow synchronous languages in an abstract algebraic syntax.

  4. This extra bit for indicating predicted resets has been missing in our publication [4] where this fixed-point analysis was introduced for the first time.

  5. In other words, the free set-theoretic “collection semantics”, which defines the completion code of a program as the set of all it possible completions (under a given choice of environments), would produce exactly the sets in \(I(\mathbb {C})\). We could have defined \(I(\mathbb {C})\) more generously as the set of subsets of completion codes \(\mathcal{P}\{ \bot , 0, 1 \}\). However, our explicit description reveals more of the algebraic properties of \(I(\mathbb {C})\) than \(\mathcal{P}\{ \bot , 0, 1 \}\). For instance, it makes clear that the internal logic of \(I(\mathbb {C})\) is not a Boolean algebra.

  6. The oversampling feature of Signal may be seen as an implicit form of reaction to absence in the asynchronous data-flow part of [77]. Synchronous reaction to absence would map \(\bot \) to \(\top \) and \(\top \) to \(\bot \) in the domain \(\mathcal {D}\) which does not seem to be expressible by the control-flow operators considered in [77].

References

  1. Abramsky, S., Jagadeesan, R., Malacaria, P.: Full abstraction for PCF. Inf. Comput. 163(2), 409–470 (2000)

    Article  MATH  MathSciNet  Google Scholar 

  2. Aceto, L., Ingolfsdottir, A.: CPO models for compact GSOS languages. Inf. Comput. 129(2), 107–141 (1996)

    Article  MATH  MathSciNet  Google Scholar 

  3. Aguado, J., Mendler, M.: Constructive semantics for instantaneous reactions. Theor. Comput. Sci. 241, 931–961 (2011)

    Article  MathSciNet  Google Scholar 

  4. Aguado, J., Mendler, M., von Hanxleden, R., Fuhrmann, I.: Grounding synchronous deterministic concurrency in sequential programming. In: Proceedings of the 23rd European Symposium on Programming (ESOP’14). LNCS 8410, pp. 229–248. Springer, Grenoble, France (2014)

  5. Aguado, J., Mendler, M., von Hanxleden, R., Fuhrmann, I.: Denotational fixed-point semantics for constructive scheduling of synchronous concurrency. Technical report 96, University of Bamberg, Faculty of Information Systems and Applied Computer Sciences (2015). ISSN 0937–3349

  6. Andalam, S., Roop, P.S., Girault, A.: Deterministic, predictable and light-weight multithreading using PRET-C. In: Proceedings of the Conference on Design. Automation and Test in Europe (DATE’10), pp. 1653–1656. Dresden, Germany (2010)

  7. Baudart, G., Mandel, L., Pouzet, M.: Programming mixed music in ReactiveML. In: Proceedings of the First ACM SIGPLAN Workshop on Functional Art. Music, Modeling & #38; Design, FARM ’13, pp. 11–22. ACM, New York, NY, USA (2013)

  8. Benveniste, A., Caillaud, B., Guernic, P.L.: Compositionality in dataflow synchronous languages: specification and distributed code generation 1,2,3. Inf. Comput. 163(1), 125–171 (2000)

    Article  MATH  Google Scholar 

  9. Benveniste, A., Caspi, P., Edwards, S.A., Halbwachs, N., Guernic, P.L., de Simone, R.: The Synchronous Languages Twelve Years Later. In: Proceedings of IEEE, Special Issue on Embedded Systems, vol. 91, pp. 64–83. IEEE, Piscataway, NJ, USA (2003)

  10. Bergstra, J., Ponse, A., Smolka, S. (eds.): Handbook of Process Algebra. Elsevier (2001)

  11. Berry, G.: The foundations of Esterel. In: Plotkin, G., Stirling, C., Tofte, M. (eds.) Proof, Language, and Interaction: Essays in Honour of Robin Milner, pp. 425–454. MIT Press, Cambridge (2000)

    Google Scholar 

  12. Berry, G.: The Constructive Semantics of Pure Esterel. Draft Book, Version 3.0, Centre de Mathématiques Appliqées, Ecole des Mines de Paris and INRIA, 2004 route des Lucioles, 06902 Sophia-Antipolis CDX, France (2002)

  13. Berry, G., Curien, P.L., Lévy, J.J.: Full abstraction for sequential languages: the state of the art. In: Nivat, M., Reynolds, J.C. (eds.) Algebraic Semantics, pp. 89–132. Cambridge University Press, Cambridge (1985)

    Google Scholar 

  14. Berry, G., Gonthier, G.: The Esterel synchronous programming language: design, semantics, implementation. Sci. Comput. Program. 19(2), 87–152 (1992)

    Article  MATH  Google Scholar 

  15. Berry, G., Nicolas, C., Serrano, M.: Hiphop: A synchronous reactive extension for Hop. In: Proceedings of the 1st ACM SIGPLAN International Workshop on Programming Language and Systems Technologies for Internet Clients. PLASTIC ’11, pp. 49–56. ACM, New York, NY, USA (2011)

  16. Boussinot, F.: Reactive C: an extension of C to program reactive systems. Softw. Pract. Exp. 21(4), 401–428 (1991)

    Article  Google Scholar 

  17. Boussinot, F.: Fairthreads: mixing cooperative and preemptive threads in C. Concurr. Comput. Pract. Exp. 18(5), 445–469 (2006)

    Article  Google Scholar 

  18. Brzozowski, J.A., Seger, C.J.H.: Asynchronous Circuits. Springer, New York (1995)

    Book  Google Scholar 

  19. Caspi, P., Pilaud, D., Halbwachs, N., Plaice, J.A.: Lustre: a declarative language for programming synchronous systems. In: Proceedings of the 14th ACM SIGACT-SIGPLAN Symposium on Principles of Programming Languages (POPL’87), pp. 178–188. ACM, Munich, Germany (1987)

  20. Caspi, P., Pouzet, M.: A co-iterative characterization of synchronous stream functions. Electron. Notes Theor. Comput. Sci. 11(0), 1–21 (1998). CMCS’98, First Workshop on Coalgebraic Methods in Computer Science

  21. Cleaveland, R., Lüttgen, G., Mendler, M.: An algebraic theory of multiple clocks. In: CONCUR ’97, LNCS, vol. 1243, pp. 166–180. Springer (1997)

  22. Cohen, A., Duranton, M., Eisenbeis, C., Pagetti, C., Plateau, F., Pouzet, M.: N-synchronous Kahn networks: a relaxed model of synchrony for real-time systems. Symposium on Principles of Programming Languages. POPL’06, pp. 180–193. ACM, New York, NY, USA (2006)

  23. Davey, B.A., Priestley, H.A.: Introduction to Lattices and Order. Cambridge University Press, Cambridge (2002)

    Book  MATH  Google Scholar 

  24. de Roever, W.P., Lüttgen, G., Mendler, M.: What is in a step: new perspectives on a classical question. In: Manna, Z., Peled, D.A. (eds.) Time for Verification, pp. 370–399. Springer LNCS 6200 (2010)

  25. Duffin, R.J.: Topology of series-parallel networks. J. Math. Anal. Appl. 10(2), 303–318 (1965)

    Article  MATH  MathSciNet  Google Scholar 

  26. Edwards, S.A.: Tutorial: compiling concurrent languages for sequential processors. ACM Trans. Design Autom. Electron. Syst. 8(2), 141–187 (2003)

    Article  Google Scholar 

  27. Edwards, S.A., Lee, E.A.: The semantics and execution of a synchronous block-diagram language. Sci. Comput. Program. 48(1), 21–42 (2003)

    Article  MATH  MathSciNet  Google Scholar 

  28. Edwards, S.A., Lee, E.A.: The semantics and execution of a synchronous block-diagram language. In: Science of Computer Programming, vol. 48. Elsevier (2003)

  29. Ésik, Z.: Axiomatizing the least fixed point operation and binary supremum. In: Clote, P., Schwichtenberg, H. (eds.) Computer Science Logic (CSL’00), LNCS 1862, pp. 302–316. Springer (2000)

  30. Fiore, M., Moggi, E., Sangiorgi, D.: A fully abstract model for the \(\pi \)-calculus. Inf. Comput. 179(1), 76–117 (2002)

    Article  MATH  MathSciNet  Google Scholar 

  31. Gamatié, A., Gonnord, L.: Static analysis of synchronous programs in Signal for efficient design of multi-clocked embedded systems. ACM Sigplan Notices 46(5), 71–80 (2011)

    Article  Google Scholar 

  32. Gemünde, M., Brandt, J., Schneider, K.: Clock refinement in imperative synchronous languages. EURASIP J. Embed. Syst. 2013, 3 (2013)

    Article  Google Scholar 

  33. Groote, J.F., Vaandrager, F.: Structured operational semantics and bisimulation as a congruence. Inf. Comput. 100, 202–260 (1992)

    Article  MATH  MathSciNet  Google Scholar 

  34. Guernic, P.L., Goutier, T., Borgne, M.L., Maire, C.L.: Programming real time applications with SIGNAL. Proc. IEEE 79(9), 1321–1336 (1991)

    Article  Google Scholar 

  35. Halbswachs, N.: Synchronous Programming of Reactive Systems. Kluwer Academic Publishers, Dordrecht (1993)

    Book  Google Scholar 

  36. Halbwachs, N., Caspi, P., Raymond, P., Pilaud, D.: The synchronous data-flow programming language LUSTRE. Proc. IEEE 79(9), 1305–1320 (1991)

    Article  Google Scholar 

  37. Hamon, G.: A denotational semantics for Stateflow. In: EMSOFT’05: Proceedings of the 5th ACM International Conference on Embedded Software, pp. 164–172. ACM Press, New York, NY, USA (2005)

  38. Harel, D.: Statecharts: a visual formalism for complex systems. Sci. Comput. Program. 8(3), 231–274 (1987)

    Article  MATH  MathSciNet  Google Scholar 

  39. Harel, D., Naamad, A.: The STATEMATE semantics of statecharts. ACM Trans. Softw. Eng. 5(4), 293–333 (1996)

    Article  Google Scholar 

  40. Hennessy, M.: Acceptance trees. J. ACM 32(4), 896–928 (1985)

    Article  MATH  MathSciNet  Google Scholar 

  41. Hennessy, M., Regan, T.: A process algebra for timed systems. Inf. Comput. 117, 221–239 (1995)

    Article  MATH  MathSciNet  Google Scholar 

  42. Hoare, C.A.R.: Communicating Sequential Processes. Prentice Hall, Upper Saddle River, NJ (1985)

    MATH  Google Scholar 

  43. Huizing, C., Gerth, R., de Roever, W.: Modeling Statecharts behavior in a fully abstract way. In: Dauchet, M., Nivat, M. (eds.) 13th CAAP (CAAP ’88). Lecture Notes in Computer Science, vol. 299, pp. 271–294. Springer, Nancy, France (1988)

  44. Hyland, M., Ong, L.: On full abstraction for PCF: I. II and III. Inf. Comput. 163(2), 285–408 (2000)

    Article  MATH  MathSciNet  Google Scholar 

  45. Ingólfsdóttir, A., Schalk, A.: A fully abstract denotational model for observational precongruence. Theor. Comput. Sci. 254(1–2), 35–61 (2001)

    Article  MATH  Google Scholar 

  46. Kahn, G.: The semantics of a simple language for parallel programming. In: Rosenfeld, J.L. (ed.) Information Processing 74: In: Proceedings of the IFIP Congress 74, pp. 471–475. North-Holland Publishing Co., IFIP (1974)

  47. Kahn, G., MacQueen, D.B.: Coroutines and networks of parallel processes. In: IFIP Congress, pp. 993–998 (1977)

  48. Kok, J.N.: Denotational semantics of nets with nondeterminism. In: Robinet, B., Wilhelm, R. (eds.) European Symposium on Programming (ESOP’86), LNCS 213, pp. 237–249. Springer (1986)

  49. Kozen, D.: A completeness theorem for Kleene algebras and the algebra of regular events. Inf. Comput. 110(2), 366–390 (1994)

    Article  MATH  MathSciNet  Google Scholar 

  50. Kuper, L., Turon, A., Krishnaswami, N.R., Newton, R.R.: Freeze after writing: Quasi-deterministic parallel programming with LVars. In: Principles of Programming Languages (POPL’14), pp. 257–270. ACM, New York, USA (2014)

  51. Lavagno, L., Sentovich, E.: ECL: a specification environment for system-level design. In: Proceedings of 36th ACM/IEEE Conference on Design Automation (DAC’99), pp. 511–516. ACM (1999)

  52. Lee, E.A., Messerschmitt, D.G.: Synchronous data flow. In: Proceedings of the IEEE, vol. 75, pp. 1235–1245. IEEE Computer Society Press (1987)

  53. Leung, A., Gupta, M., Agarwal, Y., Gupta, R., Jhala, R., Lerner, S.: Verifying GPU kernels by test amplification. In: Programming Language Design and Implementation PLDI 2012, pp. 383–394. ACM, New York, USA (2012)

  54. Luettgen, G., Mendler, M.: The intuitionism behind statecharts steps. ACM Trans. Comput. Log. 3(1), 1–41 (2002)

    Article  Google Scholar 

  55. Lüttgen, G., von der Beeck, M., Cleaveland, R.: Statecharts via process algebra. In: Proceedings of 10th International Conference on Concurrency Theory CONCUR’99, pp. 399–414 (1999)

  56. Lüttgen, G., Mendler, M.: Towards a model-theory for Esterel. In: Maraninchi, F., Girault, A., Rutten, E. (eds.) SLAP 2002, ENTCS, vol. 65,5. Elsevier Science (2002)

  57. Lynch, N.: Distributed Algorithms. Morgan Kaufmann Publishers, Los Altos (1996)

    MATH  Google Scholar 

  58. Malik, S.: Analysis of cyclic combinational circuits. IEEE Trans. Comput. Aided Des. Integr. Circuits Syst. 13(7), 950–956 (1994)

    Article  MATH  Google Scholar 

  59. Mandel, L., Pasteur, C., Pouzet, M.: Time refinement in a functional synchronous language. In: Principles and Practice of Declarative Programming (PPDP’13), pp. 169–180. ACM (2013)

  60. Mandel, L., Pouzet, M.: ReactiveML: a reactive extension to ML. In: Proceedings of 7th ACM SIGPLAN Int’l Conference on Principles and Practice of Declarative Programming, pp. 82–93 (2005)

  61. Maraninchi, F.: The Argos language: graphical representation of automata and description of reactive systems. In: IEEE Workshop on Visual Languages (1991)

  62. Maraninchi, F., Rémond, Y.: Argos: an automaton-based synchronous language. Comput. Lang. 27(27), 61–92 (2001)

    Article  MATH  Google Scholar 

  63. Mendler, M., Lüttgen, G.: Is observational congruence axiomatisable in equational Horn logic? Inf. Comput. 208(6), 634–651 (2010)

    Article  MATH  Google Scholar 

  64. Mendler, M., Shiple, T.R., Berry, G.: Constructive boolean circuits and the exactness of timed ternary simulation. Form. Methods Syst. Des. 40(3), 283–329 (2012)

    Article  MATH  Google Scholar 

  65. Milner, R.: Communication and Concurrency. Prentice Hall, Englewood Cliffs (1989)

    MATH  Google Scholar 

  66. Motika, C., von Hanxleden, R., Heinold, M.: 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 (2013)

  67. Ngo, V.C., Talpin, J.P., Gautier, T.: Precise deadlock detection for polychronous data-flow specifications. In: Proceedings of the Electronic System Level Synthesis Conference (ESLsyn), pp. 1–6. IEEE (2014)

  68. Plotkin, G.D.: A Structural Approach to Operational Semantics. Technical report DAIMI FN-19, University of Aarhus, Denmark (1981)

  69. Pnueli, A., Shalev, M.: What is in a step: on the semantics of Statecharts. In: Proceedings of International Conference on Theoretical Aspects of Computer Software (TACS’91), pp. 244–264. Springer, London, UK (1991)

  70. Potop-Butucaru, D., Edwards, S.A., Berry, G.: Compiling Esterel. Springer, Berlin (2007)

    Google Scholar 

  71. Pouzet, M., Raymond, P.: Modular static scheduling of synchronous data-flow networks—an efficient symbolic representation. Des. Autom. Embed. Syst. 14(3), 165–192 (2010)

    Article  Google Scholar 

  72. Schneider, K.: The synchronous programming language Quartz. Internal Report 375, Department of Computer Science, University of Kaiserslautern, Kaiserslautern, Germany (2009)

  73. Schneider, K., Brandt, J., Schuele, T.: Causality analysis of synchronous programs with delayed actions. In: Conference on Compilers, Architecture, and Synthesis for Embedded Systems (CASES’04), pp. 179–189. ACM, Washington DC, USA (2004)

  74. Schneider, K., Brandt, J., Schuele, T., Tuerk, T.: Maximal causality analysis. In: Conference on Application of Concurrency to System Design (ACSD’05), pp. 106–115. IEEE Computer Society (2005)

  75. Schneider, K., Brandt, J., Schüle, T., Türk, T.: Improving constructiveness in code generators. In: Maraninchi, F., Pouzet, M., Roy, V. (eds.) International Workshop on Synchronous Languages, Applications, and Programming (SLAP’05), pp. 1–19. ENTCS, Edinburgh, Scotland, UK (2005)

  76. Shiple, T.R., Berry, G., Touati, H.: Constructive Analysis of Cyclic Circuits. In: Proceedings of European Design and Test Conference (ED&TC’96), Paris, France, pp. 328–333. IEEE Computer Society Press (1996)

  77. Talpin, J.P., Brandt, J., Gemünde, M., Schneider, K., Shukla, S.: Constructive polychronous systems. Sci. Comput. Program. 96(3), 377–394 (2014)

    Article  Google Scholar 

  78. Talpin, J.P., Ouy, J., Gautier, T., Besnard, L., Guernic, P.L.: Compositional design of isochronous systems. Sci. Comput. Program. 77(2), 113–128 (2012)

    Article  MATH  Google Scholar 

  79. Tardieu, O., Edwards, S.A.: Scheduling-independent threads and exceptions in SHIM. In: Proceedings of the International Conference on Embedded Software (EMSOFT’06), pp. 142–151. ACM (2006)

  80. Tardieu, O., Edwards, S.A.: Instanteneous transitions in Esterel. In: Proceedings of Model Driven High-Level Programming of Embedded Systems (SLA++P’07). Braga, Portugal (2007)

  81. Vechev, M., Yahav, E., Raman, R., Sarkar, V.: Automatic verification of determinism for structured parallel programs. In: Cousot, R., Martel, M. (eds.) Static Analysis (SAS 2010), LNCS, vol. 6337, pp. 455–471. Springer (2010)

  82. von der Beeck, M.: A comparison of Statecharts variants. In: Langmaack, H., de Roever, W., Vytopil, J. (eds.) 3rd International School and Symposium on Formal Techniques in Real-Time and Fault-Tolerant Systems (FTRTFT ’94), Lecture Notes in Computer Science, vol. 863, pp. 128–148. Springer (1994)

  83. von Hanxleden, R.: SyncCharts in C-A Proposal for Light-Weight, Deterministic Concurrency. In: Proceedingsof International Conference on Embedded Software (EMSOFT’09), pp. 225–234. ACM, Grenoble, France (2009)

  84. von Hanxleden, R., Duderstadt, B., Motika, C., Smyth, S., Mendler, M., Aguado, J., Mercer, S., O’Brien, O.: SCCharts: sequentially constructive statecharts for safety-critical applications. In: Proceedings of ACM SIGPLAN Conference on Programming Language Design and Implementation (PLDI’14). ACM (2014)

  85. von Hanxleden, R., Mendler, M., Aguado, J., Duderstadt, B., Fuhrmann, I., Motika, C., Mercer, S., O’Brien, O.: Sequentially constructive concurrency—a conservative extension of the synchronous model of computation. In: Design, Automation and Test in Europe (DATE’13), pp. 581–586. IEEE (2013)

  86. von Hanxleden, R., Mendler, M., Aguado, J., Duderstadt, B., Fuhrmann, I., Motika, C., Mercer, S., O’Brien, O., Roop, P.: Sequentially constructive concurrency—a conservative extension of the synchronous model of computation. ACM Trans. Embed. Comput. Syst.,Special Issue on Applications of Concurrency to System Design 13(4s), 144:1–144:26 (2014)

  87. Yuki, T., Feautrier, P., Rajopadye, S., Saraswat, V.: Array dataflow analysis for polyhedral X10 programs. In: Principles and Practice of Parallel Programming (PPoPP 2013), pp. 23–34. ACM (2013)

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Acknowledgments

This work has been supported by the German National Research Council DFG as part of the PRETSY Project (HA 4407/6-1, ME 1427/6-1). The authors would also like to thank the anonymous reviewers for their trenchant yet constructive criticisms and their useful suggestions regarding related work and expository improvements of the paper.

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Aguado, J., Mendler, M., von Hanxleden, R. et al. Denotational fixed-point semantics for constructive scheduling of synchronous concurrency. Acta Informatica 52, 393–442 (2015). https://doi.org/10.1007/s00236-015-0238-x

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