An automatic scratch pad memory management tool and MPEG-4 encoder case study

ABSTRACT

Using software-controlled Scratch-Pad Memory (SPM) in Systems-on-Chip has the potential of reducing power consumption by using design-time application knowledge to reduce memory accesses and processor stalls. This paper presents a fully automatic application analysis and transformation tool which selects data-structures for transfer to the SPM and schedules data transfers between background memory and SPM (pre-fetching) to achieve both high performance and low power consumption. A case study applying this tool on an MPEG-4 video encoder shows an overall power reduction of 25%, a 40% power reduction in just the memories and a 40% reduction in processor cycles as compared to an optimized hardware-cache based solution.

REFERENCES

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INDEX TERMS

Primary Classification:
  C. Computer Systems Organization
  C.3 SPECIAL-PURPOSE AND APPLICATION-BASED SYSTEMS

Additional Classification:
  D. Software
  D.3 PROGRAMMING LANGUAGES
      D.3.4 Processors
          Subjects: Compilers

General Terms:
Design, Performance

Keywords:
MPEG-4, cache, memory hierarchy, scratch-pad