摘要:

AbstractAdam is a high‐level language for parallel processing. It is intended for programming resource scheduling applications, in particular supervisory packages for run‐time scheduling of multiprocessing systems. An important design goal was to provide support for implementation of Ada and its run‐time environment. Adam has been used to implement Ada task supervision and also as a high‐level target language for compilation of Ada tasking.Adam provides facilities corresponding to the Ada sequential constructs (including subprograms, packages, exceptions, generics). In addition, it provides specialized module constructs for implementation of packages that may be shared between parallel processes, and new predefined types for scheduling. The parallel processing constructs of Adam are more primitive than Ada tasking. Strong restrictions are enforced on the ways in which parallel processes can interact.A compiler for Adam has been implemented in MacLisp on DEC PDP‐10 computers. Runtime support packages in Adam for scheduling (on a single CPU) and I/O are also provided. The compiler contains a library manipulation facility for separate compilation.The Adam compiler has been used to build an Ada compiler for most of the July 1980 Ada, including task types and rendezvous constructs. This was achieved by implementing the translation of Ada tasking into Adam parallel processing as a preprocessor to the Adam compiler. This present Ada compiler, which has been operational since December 1980, uses a procedure call implementation of tasking. It can be easily modified to other implementations. Compilation of Ada tasking into a high‐level target language such as Adam facilitates studying questions of correctness and efficiency of various compilation algorithms, and code optimizations specific to tasking, e.g. elimination of unnecessary threads of control.This paper gives an overview of Adam and examples of its use. Emphasis is placed on the differences from Ada. Experience using Adam to build the experimental Ada system is evaluated. Design of a run‐time supervisor in Adam is discus

ISSN:0038-0644    

DOI:10.1002/spe.4380140702

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

摘要:

AbstractThis paper reports the work on implementing a parallel version of Pascal on a small scale multiprocessor computer. A few simple primitives were included to support parallel programming. The code generation, linking and loading procedures are described. An overview of the hardware is included. Finally some programming experience with the system is reported.

ISSN:0038-0644    

DOI:10.1002/spe.4380140703

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

摘要:

AbstractA package implemented using standard Pascal is described. It provides the user with basic tools for discrete event‐orientated simulation, and includes facilities for scheduling and causing pending events, handling of LIFO and FIFO queues, control of periodical dumping of statistics and comprehensive initialization and error routines.Two versions of the package have been implemented, using tree and linked list structures for scheduled events. Their relative performances are compared. The tree structure proves to be more efficient except in the minority of cases where the set of scheduled events has to be searched frequently; it also provides a much more efficient scheduling algorithm than does a linked list structure.This package is primarily intended as a communication network design tool, and a simple example of this type of usage is included. It could also be used in undergraduate teaching. Coding examples are given for the main procedures, in the two implementation

ISSN:0038-0644    

DOI:10.1002/spe.4380140704

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

摘要:

AbstractThe process interaction approach is proposed for developing a discrete simulation environment in Ada. The introduction of simulation facilities in Ada not only concerns the classical aspect of model building, but allows a new class of problems to be tackled, that is the testing of correctness of programs intended for real‐time applications. In this paper attention is focused on the presentation of the process scheduling in the simulation context and on the definition of standard forms of interactions among processes. Simulation facilities are organized by making use of Ada's structuring concept

ISSN:0038-0644    

DOI:10.1002/spe.4380140705

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

摘要:

AbstractThe programming language PL/I is considered as a most useful and portable discrete event simulation tool. This paper discusses design facilities required in simulation languages, making use of a model described in PL/I. The problem of queues, parallelism and synchronization in a simulator is solved. The structure of the simulator is considered.

ISSN:0038-0644    

DOI:10.1002/spe.4380140706

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

ISSN:0038-0644    

DOI:10.1002/spe.4380140707

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

ISSN:0038-0644    

DOI:10.1002/spe.4380140708

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

ISSN:0038-0644    

DOI:10.1002/spe.4380140701

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY