4 ms·

This takes me back to the early 80s when "Personal Computer World" (UK) used to have a letters column called "Subset", where people would share short assembler

by Starwatcher2001 8y ago

This takes me back to the early 80s when "Personal Computer World" (UK) used to have a letters column called "Subset", where people would share short assembler routines for the 8 bit chips of the time. People would share optimisations, hidden opcodes, quirks about the chips etc. Often there'd be posts that shaved a byte or two or a few t-states off a previous months post. It's amazing how inventive people can be with limited resources. It seems that as processors are so fast and memory so abundant now that squeezing the last drop of efficiency from a routine is a dying art. https://en.wikipedia.org/wiki/Personal_Computer_World https://en.wikipedia.org/wiki/Personal_Computer_World Many of the Z80 and 6502 routines have been collected together into a couple of books, mentioned here: http://mycodehere.blogspot.com/2011/10/my-work-in-print-1985.html http://mycodehere.blogspot.com/2011/10/my-work-in-print-1985...

iainmerrick 8y ago
A dying art? Yes and no... There have been quite a few recent articles posted here about squeezing the maximum performance out of compression algorithms, say, by clever use of SIMD operations. It’s certainly less common now to be quite so concerned with shaving individual bytes off the code size. But I bet that still comes up when generating function prologues/epilogues/trampolines etc in compiler output -- stuff that will appear a lot in the output, so even one word saved will be significant.
- seandougall 8y ago
  And I imagine the energy savings of such a change over billions of devices can be phenomenal in some cases. I’m glad there are still people working on these things. I think it’s true, though, that it’s now a much narrower subset of people — it’s not really desirable or practical for most hobbyists to dive deep into assembly, the way I remember seeing back in the ‘80s.

iainmerrick 8y ago

A dying art? Yes and no... There have been quite a few recent articles posted here about squeezing the maximum performance out of compression algorithms, say, by clever use of SIMD operations. It’s certainly less common now to be quite so concerned with shaving individual bytes off the code size. But I bet that still comes up when generating function prologues/epilogues/trampolines etc in compiler output -- stuff that will appear a lot in the output, so even one word saved will be significant.

seandougall 8y ago
And I imagine the energy savings of such a change over billions of devices can be phenomenal in some cases. I’m glad there are still people working on these things. I think it’s true, though, that it’s now a much narrower subset of people — it’s not really desirable or practical for most hobbyists to dive deep into assembly, the way I remember seeing back in the ‘80s.