Compiler-Driven Leakage Energy Reduction in Banked Register Files

  • David Atienza
  • Praveen Raghavan
  • José L. Ayala
  • Giovanni De Micheli
  • Francky Catthoor
  • Diederik Verkest
  • Marisa Lopez-Vallejo
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4148)


Tomorrow’s embedded devices need to run high-resolution multimedia applications which need an enormous computational complexity with a very low energy consumption constraint. In this context, the register file is one of the key sources of power consumption and its inappropriate design and management can severely affect the performance of the system. In this paper, we present a new approach to reduce the energy of the shared register file in upcoming embedded VLIW architectures with several processing units. Energy savings up to a 60% can be obtained in the register file without any performance penalty. It is based on a set of hardware extensions and a compiler-based energy-aware register assignment algorithm that enable the de/activation of parts of the register file (i.e. sub-banks) in an independent way at run-time, which can be easily included in these embedded architectures.


Bank Register Register Allocation Shared Register Very Long Instruction Word Dynamic Voltage Scaling 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • David Atienza
    • 1
    • 2
  • Praveen Raghavan
    • 3
    • 4
  • José L. Ayala
    • 5
  • Giovanni De Micheli
    • 1
  • Francky Catthoor
    • 3
    • 4
  • Diederik Verkest
    • 3
    • 6
  • Marisa Lopez-Vallejo
    • 5
  1. 1.Laboratoire des Systemes Integres (LSI)Ecole Polytechnique Federale de Lausanne (EPFL)Switzerland
  2. 2.Computer Architecture and Automation Department (DACYA)Universidad Complutense de Madrid (UCM)Spain
  3. 3.Digital Design Technology Group (DDT)Inter-University Micro-Electronics Center (IMEC) vzwHeverleeBelgium
  4. 4.ESATKatholic University of Leuven (KUL)HeverleeBelgium
  5. 5.Depto. de Ingenieria Electronica (DIE)Universidad Politecnica de Madrid, (UPM)Spain
  6. 6.Electrical EngineeringVrije UniversiteitBrusselsBelgium

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