Amagbegnon, P., Besnard, L., Guernic, P.L.: Implementation of the Dataflow Synchronous Language Signal. In: Conference on Programming Language Design and Implementation, La Jolla, California (1995) 163--173  Home/Search   Document Not in Database   Summary   Related Articles   Check

....operations, the only link in between the time and the behavioral operations is due to the definition of time passing. This aspect differentiate our approach from others. For example, the notion of local clocks and a calculus for synchronizing local clocks, is also presented in the language SIGNAL [1, 11]. There, a clock is associated with a signal and clocks can be of different frequencies. The calculus of clocks at compilation time allows the construction of a forest of clocks associated with the program, the primitive operators of the calculus explicitly take the clocks into account and might ....

Amagbegnon,T.P., Besnard,L., Le Guernic,P.: Implementation of the data-flow Synchronous Language Signal. Proc. ACM Symposium on Programming Languages design and ImplementationACM (1995) 163-173.

.... all system components must synchronize) nor in [7, 14, 10] where the local clocks are assumed to elapse in the same way (by making the system components running at the same speed) The notion of local clocks and a calculus for synchronizing local clocks, is also presented in the language SIGNAL [1, 11]. There, a clock is associated with a signal and clocks can be of different frequencies. Although the notion of local clocks and of their calculus might resemble our approach, the use of these notions in the two approaches is different. 2 The Language and Its Transitional Semantics We adopted a ....

Amagbegnon,T.P., Besnard,L., Le Guernic,P.: Implementation of the data-flow Synchronous Language Signal. Proc. ACM Symposium on Programming Languages design and ImplementationACM (1995) 163-173.

....which have the property to get smaller when the variable ordering make adjacent variables appearing often in conjunctive form [21] Secondly, one may reason by using the properties of the frequency pre order implied by this operator. It is this second kind of technique which makes clock calculus [19, 2] of Signal particularly efficient. iii) On Implementation Being basically a Mealy machine, a Synchronous Automaton reacts and then reaches a new state that is, with respect to the distributed representation of states, assigning a new status to any of its registers. Therefore, the transition ....

P. Amagbegnon, L. Besnard, and P. Le Guernic. Implementation of the data-flow synchronous language Signal. In Proc. of ACM-SIGPLAN conference on Programming Language Design and Implementation, pages 163--173, June 1995.

.... outlined in the figure 4) Using the graph g produced by clock calculus, the Signal compiler generates an optimal compile time scheduling of the actions specified in the source program by hierarchizing the temporal relations in g and by ruling the execution of the program using its master clock [2]. Using the graph g, causal dependencies in the source program can easily be detected as constrained boolean conditions on signals (e.g. x] y) or cyclic data dependencies (e.g. x c Gamma x) x : v ) x : y 1 ) Gamma x = y Delta x : y when z ) y [z] Gamma x x = y ....

T. P. Amagbegnon, L. Besnard and P. Le Guernic. Implementation of the data-flow synchronous language Signal. In Proceedings of the 1995's ACM Conference on Programming Language Design and Implementation, p. 163--173. ACM, 1995.

.... 0 ) 00 ffi 1 timer(60) bool ffi 1 1 bool ffi 1 ) ffi 1 1 ffi 1 ; ffi 2 timer(100) bool ffi 2 2 bool ffi 2 ) ffi 2 2 4 Causal Invariants The clock calculus allows the compilation of parallelism within a process by defining a hierarchy of tasks according to clock relations [1] (see section 5) To generate executable code, additional information on the causal dependencies between signals is needed in order to serialize the emission of outputs in each task. In Signal, this information is obtained by a flow analysis [2] This analysis detects cyclic causal dependencies, ....

....An endochronous system reacts to inputs (by having clocks computable from that of its inputs) and terminates within a predictable amount of time (by avoiding deadlocks and recursions) Hierarchization is the implementation of endochrony. It is the medium used in Signal for compiling parallelism [1]. It consists of organizing the environment Gamma as a tree Theta that defines a correct scheduling of computations into tasks. Each node of the tree consists of synchronous signals. It denotes the task of computing them when the clock is active. Each relation of a node with a sub tree ....

T. P. Amagbegnon, L. Besnard, P. Le Guernic. Implementation of the data-flow synchronous language Signal. In Conference on Programming Language Design and Implementation. Acm, 1995.

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Amagbegnon, T. P., Besnard, L., Le Guernic, P. "Implementation of the data-flow synchronous language Signal". In Conference on Programming Language Design and Implementation. ACM Press, 1995.

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AMAGBEGNON, T. P., BESNARD, L., LE GUERNIC, P. "Implementation of the data-flow synchronous language SIGNAL". In Conference on Programming Language Design and Implementation. ACM Press, 1995.

.... Phi i;j = Phi Gamma i k Phi Gamma j ) The objective of the selection procedure is to avoid intermediate explosion of the size of the partial hierarchies built in this way. Such a selection procedure involves heuristics, it is very similar to the clock calculus implemented in Signal compiler [1]. To summarize the results of this section, we have solved the issues related to correct deployment : we now have at our disposal the concepts and algorithms for equipping a Bdl design with the hybrid synchronous asynchronous semantics suited to deployment, while preserving semantic equivalence ....

T. P. Amagbegnon, L. Besnard and P. Le Guernic. Implementation of the data-flow synchronous language Signal. In Conference on Programming Language Design and Implementation. Acm, 1995.

....built, by successive refinements of the main clock of the program. At the opposite, Signal programs can be built bottom up by composing abstracted processes used as black boxes . As the composition may result in new clocks, the description produced is in general case a forest of clock hierarchies [12]. To insure deterministic implementations, we say that Signal descriptions are implementable when the forest of clock hierarchies is reduced to a tree; this way a single main clock of the program rules the execution. In all cases, we know that a flow is present at least as often as all the other ....

T. Pascalin Amagbegnon, Loic Besnard, and Paul Le Guernic. Implementation of the data-flow synchronous language Signal. In Programming Languages Design and Implementation, pages 163--173. ACM, ACM, 1995.

.... Phi i;j = Phi Gamma i k Phi Gamma j ) The objective of the selection procedure is to avoid intermediate explosion of the size of the partial hierarchies built in this way. Such a selection procedure involves heuristics, it is very similar to the clock calculus implemented in Signal compiler [1]. To summarize the results of this section, we have solved the issues related to correct deployment : we now have at our disposal the concepts and algorithms for equipping a Bdl design with the hybrid synchronous asynchronous semantics suited to deployment, while preserving semantic equivalence ....

T. P. Amagbegnon, L. Besnard and P. Le Guernic. Implementation of the data-flow synchronous language Signal. In Conference on Programming Language Design and Implementation. Acm, 1995.

.... specifications 8x1: n :g Using the graph g produced by the clock calculus, the Signal compiler generates an optimal compile time scheduling of the actions specified in the source program by hierarchizing temporal relations in g and by ruling the execution of the program using its master clock [1]. Using the graph g, causal dependencies in the source program can easily be detected as constrained boolean conditions on signals (e.g. x] y) or cyclic data dependencies (e.g. x c Gamma x) This allows proving the absence of dead locks in the program. Example As the conditional data flow ....

....a clock equation in g 0 cannot induce a causal dependency of the form [y] c in g. Refinement Checking Checking satisfaction of the relation g g 0 amounts to solving the problem g 0 ) g. As g 0 and g are systems of boolean equations, this problem can be expressed on Z=2Z [1] as g : P i ( Gamma x ) 0) i2I and g 0 : P 0 j ( Gamma x ) 0) j2J where the formula P i and P 0 j (of index I and J) are polynomials on Z=2Z and where Gamma x is the vector of signals defined in the system of equations. Now, let us define the boolean operator Phi as a ....

T. P. Amagbegnon, L. Besnard and P. Le Guernic. Implementation of the data-flow synchronous language Signal. In Proceedings of the 1995's ACM Conference on Programming Language Design and Implementation, p. 163--173. ACM, 1995.

No context found.

Amagbegnon, P., Besnard, L., Guernic, P.L.: Implementation of the Dataflow Synchronous Language Signal. In: Conference on Programming Language Design and Implementation, La Jolla, California (1995) 163--173

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