The Liberty Simulation Environment: A deliberate approach to high-level system modeling

ABSTRACT

In digital hardware system design, the quality of the product is directly related to the number of meaningful design alternatives properly considered. Unfortunately, existing modeling methodologies and tools have properties which make them less than ideal for rapid and accurate design-space exploration. This article identifies and evaluates the shortcomings of existing methods to motivate the Liberty Simulation Environment (LSE). LSE is a high-level modeling tool engineered to address these limitations, allowing for the rapid construction of accurate high-level simulation models. LSE simplifies model specification with low-overhead component-based reuse techniques and an abstraction for timing control. As part of a detailed description of LSE, this article presents these features, their impact on model specification effort, their implementation, and optimizations created to mitigate their otherwise deleterious impact on simulator execution performance.

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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.6 SIMULATION AND MODELING
      I.6.2 Simulation Languages

Additional Classification:
  C. Computer Systems Organization
  C.4 PERFORMANCE OF SYSTEMS
      Subjects: Modeling techniques

  I. Computing Methodologies
  I.6 SIMULATION AND MODELING
      I.6.5 Model Development
          Subjects: Modeling methodologies
      I.6.7 Simulation Support Systems
          Subjects: Environments

General Terms:
Design, Experimentation, Human Factors, Languages

Keywords:
Liberty Simulation Environment (LSE), component reuse, simulator construction, structural modeling