5 ms·

x86-64 is anything but "boring" and "safe". :) Real mode, Mod R/M and SIB byte encoding weirdness, REX prefixes, 80-bit floats, parity flag, hard-wired registe

x86-64 is anything but "boring" and "safe". :) Real mode, Mod R/M and SIB byte encoding weirdness, REX prefixes, 80-bit floats, parity flag, hard-wired registers for shifts/multiplies/divisions, builtin CRC32 over the wrong polynomial, Pascal calling convention support, binary-coded decimal, high halves of 16-bit registers, MMX overlap with x87 floating point, etc. etc.

q3k 8y ago
Right, but most of these are just past crimes^W^Wlegacy that Intel has to deal with in the name of backwards compatibility.
- Klathmon 8y ago
  >most of these are just past crimes^W^Wlegacy This is completely off topic, but I've seen things like the "^W^W" a few times before, and I don't know what it means. Is this a weird encoding mismatch thing? is it from some editor/system that people instinctively type? Is it from some other forum which has a strange markup syntax for something?
  - SteveCoast 8y ago
    Delete word.
  - q3k 8y ago
    Emacs/readline bindings for Delete Word. Open up a bash shell, type in `foo bar baz`, then press ctrl-W twice. '^W' is what would appear instead if you weren't in a readline/emacs editor, but instead a dumb line terminal. Thus, leaving '^W' behind makes it look like you didn't realize what you just corrected is still visible. It's a joke. I've now explained and ruined it.
    - Klathmon 8y ago
      Ah okay makes sense! It's amazing the gaps in knowledge I still have with a lot of things. I've used Linux daily for like 15 years now, and I know about control characters, but since I never really used emacs (or readline beyond the copy+pasted command here or there) I just completely missed the meaning.
    - bluedino 8y ago
      Slashdot posters would use ^H^H in their posts (backspace)
      - lscotte 8y ago
        It goes back way further than that - probably to the dawn of IRC or so.
        pjscott 8y ago
        I believe it dates back to the unix talk(1) program, quite a bit earlier than IRC.
        TheCondor 8y ago
        It’s from the dec terminal emulation, VT100. I think specifically when you connected to like an ansi type system with dec mode. Or something like that, the memories are fuzzy
        lscotte 8y ago
        The keystroke certainly does, but I was talking about people inserting ^h and ^w in the middle of conversations, which is a bit harder to nail down, though the practice is older than the parent thought.
        mark-r 8y ago
        ^H was backspace on teletypes, which probably dates back to the 1960's.
    - yuubi 8y ago
      Not emacs (it means kill-region there, which deletes the text between the cursor and the mark and saves it in a holding area, fairly close to what windows does when you hit ^x, except the holding area is fancier). This readline behavior follows a Unix tty driver. I'm not sure off the top of my head which one introduced it. I don't think it was on xenix but am pretty sure some 4.x bsd had it.
    - Angostura 8y ago
      In days of yore the joke was always ^H^H after IBM/DEC backspace v delete confusion
  - aeneasmackenzie 8y ago
    ^W deletes the last word in readline.
    - dorfsmay 8y ago
      In readline in emacs mode (yes you can switch deadline in vi mode)
  - deleted 8y ago
    [deleted]
  - otabdeveloper2 8y ago
    "^W" is this guy: https://en.wikipedia.org/wiki/End-of-Transmission-Block_character https://en.wikipedia.org/wiki/End-of-Transmission-Block_char... In Unix line editors it is traditionally used to mean 'erase the previous word'. See also documentation for ASCII (http://www.robelle.com/smugbook/ascii.html http://www.robelle.com/smugbook/ascii.html for example) for origins of ^C, ^D, ^S, etc.
    - nonamenoslogan 8y ago
      As an HP3000 programmer I still refer to this link fairly often. Ah MPE, its a strange one.
  - lemoncucumber 8y ago
    It’s used the same way strikethrough is used, for reasons others have explained.
twtw 8y ago
I thought it was fairly clear 'q3k was referring to the 64 bit ISA introduced in amd64, not all the legacy stuff either kept around in some form for compatibility (x87, encodings) or stuff that isn't part of long mode (BCD, segmentation, real mode).
ori_b 8y ago
It's boring and safe by virtue of familiarity.

q3k 8y ago

Right, but most of these are just past crimes^W^Wlegacy that Intel has to deal with in the name of backwards compatibility.

Klathmon 8y ago
>most of these are just past crimes^W^Wlegacy This is completely off topic, but I've seen things like the "^W^W" a few times before, and I don't know what it means. Is this a weird encoding mismatch thing? is it from some editor/system that people instinctively type? Is it from some other forum which has a strange markup syntax for something?
- SteveCoast 8y ago
  Delete word.
- q3k 8y ago
  Emacs/readline bindings for Delete Word. Open up a bash shell, type in `foo bar baz`, then press ctrl-W twice. '^W' is what would appear instead if you weren't in a readline/emacs editor, but instead a dumb line terminal. Thus, leaving '^W' behind makes it look like you didn't realize what you just corrected is still visible. It's a joke. I've now explained and ruined it.
  - Klathmon 8y ago
    Ah okay makes sense! It's amazing the gaps in knowledge I still have with a lot of things. I've used Linux daily for like 15 years now, and I know about control characters, but since I never really used emacs (or readline beyond the copy+pasted command here or there) I just completely missed the meaning.
  - bluedino 8y ago
    Slashdot posters would use ^H^H in their posts (backspace)
    - lscotte 8y ago
      It goes back way further than that - probably to the dawn of IRC or so.
      - pjscott 8y ago
        I believe it dates back to the unix talk(1) program, quite a bit earlier than IRC.
        TheCondor 8y ago
        It’s from the dec terminal emulation, VT100. I think specifically when you connected to like an ansi type system with dec mode. Or something like that, the memories are fuzzy
        lscotte 8y ago
        The keystroke certainly does, but I was talking about people inserting ^h and ^w in the middle of conversations, which is a bit harder to nail down, though the practice is older than the parent thought.
      - mark-r 8y ago
        ^H was backspace on teletypes, which probably dates back to the 1960's.
  - yuubi 8y ago
    Not emacs (it means kill-region there, which deletes the text between the cursor and the mark and saves it in a holding area, fairly close to what windows does when you hit ^x, except the holding area is fancier). This readline behavior follows a Unix tty driver. I'm not sure off the top of my head which one introduced it. I don't think it was on xenix but am pretty sure some 4.x bsd had it.
  - Angostura 8y ago
    In days of yore the joke was always ^H^H after IBM/DEC backspace v delete confusion
- aeneasmackenzie 8y ago
  ^W deletes the last word in readline.
  - dorfsmay 8y ago
    In readline in emacs mode (yes you can switch deadline in vi mode)
- deleted 8y ago
  [deleted]
- otabdeveloper2 8y ago
  "^W" is this guy: https://en.wikipedia.org/wiki/End-of-Transmission-Block_character https://en.wikipedia.org/wiki/End-of-Transmission-Block_char... In Unix line editors it is traditionally used to mean 'erase the previous word'. See also documentation for ASCII (http://www.robelle.com/smugbook/ascii.html http://www.robelle.com/smugbook/ascii.html for example) for origins of ^C, ^D, ^S, etc.
  - nonamenoslogan 8y ago
    As an HP3000 programmer I still refer to this link fairly often. Ah MPE, its a strange one.
- lemoncucumber 8y ago
  It’s used the same way strikethrough is used, for reasons others have explained.

twtw 8y ago

I thought it was fairly clear 'q3k was referring to the 64 bit ISA introduced in amd64, not all the legacy stuff either kept around in some form for compatibility (x87, encodings) or stuff that isn't part of long mode (BCD, segmentation, real mode).

ori_b 8y ago

It's boring and safe by virtue of familiarity.