STATIC SOFTWARE SCHEMES Fast Selective invalidation

Fast selective invalidation

• Cheong & Veidenbaum, 1988, Univ. of Illinois

• Essence: invalidation is executed in 1 cycle (fast) and affects only unsafe references (selective)

• HW support:

  • Change bit (per line) - set by Invalidate instruction
  • Clear bit (per line) - set by Clear instruction
  • Invalidate and Clear instructions

• SW support:

  • reference marking (cache-read - safe, memory-read - unsafe)
  • insertion of Invalidate instructions
    (before Serial loop, at the begining of DoAll loop)

• Intra-epoch restrictive, inter-epoch conservative