Application of Church-Rosser properties to increase the parallelism and efficiency of algorithms

  • Mariangiola Dezani-Ciancaglini
  • Maddalena Zacchi
Tuesday Morning
Part of the Lecture Notes in Computer Science book series (LNCS, volume 14)


Besides the Church-Rosser property (here called full), three other commutativity properties of transformations (the mutual, inner and strong Church-Rosser property) are also defined, which are less restrictive than the first. These properties are used to decide:
  1. 1)

    when and how the rules belonging to the same loop can be applied in parallel

  2. 2)

    when a rule can be eliminated

  3. 3)

    when a rule can be removed from a loop.


The transformations of algorithms our methods yield are particularly significant in that they depend only on the semantics of the original algorithm, i.e., the input-output relations.

To perform the parallelization (point 1), a new model of structured programming language is used, sufficiently general to ensure that every program can be automatically translated into a structured one.


Computation Scheme Sequential Computation Stop Rule International Summer School Connected Finite Graph 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1974

Authors and Affiliations

  • Mariangiola Dezani-Ciancaglini
    • 1
  • Maddalena Zacchi
    • 1
  1. 1.Istituto di Scienza dell'Informazione dell'Università di TorinoTorino

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