@techreport{TR-IC-99-12,
  number = {IC-99-12},
  author = {Ricardo Pannain and Paulo Centoducatte and Guido Araújo},
  title = {Using Operand Factorization to Compress {DSP} Programs},
  month = {April},
  year = {1999}, 
  institution = {Institute of Computing, University of Campinas},
  note = {In English, 14 pages.
    \par\selectlanguage{english}\textbf{Abstract}
      We propose a method for compressing programs running on embedded
      DSPs. Program expression trees are decomposed into opcode and
      operand sequences called patterns. We show that DSP program
      patterns have exponential frequency distributions. Based on
      that, we encode patterns using a mix of variable-length and
      fixed-length codewords. A decompression engine is proposed,
      which converts patterns into uncompressed instruction sequences.
      The experimental results reveal an average compression ratio of
      67{\%} for typical DSP programs running on the TMS320C25
      processor. This ratio includes an estimate of the size of the
      decompression engine.
  }
}