I see many references to a paper by Andrew Tanenbaum that demonstrated the vast majority of constants would fit into 13-bits, and I seem to recall it being in my university text on CPU design. However, I can't find a reference to it. Does anyone have a pointer?

  • 2
    Looking at a few Google references to this. It seems like everybody knows somebody who thinks Tanembaum wrote it, but nobody has ever seen the original document :)
    – alephzero
    Jun 17, 2019 at 12:22
  • Maybe this list would provide some help.
    – DroidW
    Jun 17, 2019 at 12:40
  • For the record, I wrote to Andy and he sent me a much better copy of the paper. :-) Jun 18, 2019 at 11:50

1 Answer 1


Andrew Tanenbaum wrote two papers about operand encoding, instruction sizes, and the representations of structured programming constructs, which sounds like what you’re looking for: Implications of structured programming for machine architecture (Communications of the ACM, March 1978) and Efficient encoding of machine instructions (ACM SIGARCH Computer Architecture News, June 1979).

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.