Sujet : Re: Byte ordering
De : jgd (at) *nospam* cix.co.uk (John Dallman)
Groupes : comp.archDate : 05. Jan 2025, 15:48:26
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <memo.20250105144856.20984i@jgd.cix.co.uk>
References : 1
In article <
2025Jan3.093849@mips.complang.tuwien.ac.at>,
anton@mips.complang.tuwien.ac.at (Anton Ertl) wrote:
The 8086 has branches with 8-bit offsets and branches and calls
with 16-bit offsets. The 386 in 32-bit mode has branches with
8-bit offsets and branches and calls with 32-bit offsets; if
16-bit offsets for branches would be useful enough for performance,
they could instead have designed the longer branch length to be
16 bits, and maybe a prefix for 32-bit branch offsets. That would
be faster than what you outline, as soon as one call happens.
But apparently 16-bit branches are not that beneficial, or they
would have gone that way on the 386.
Don't assume that Intel of the early 1980s would have done enough
simulation to explore those possibilities thoroughly. Given the mistakes
they made in the 1970s with iAPX 432 and in the 1990s with Itanium, both
through lack of simulation with varying workloads, they may well have
been working by rules of thumb and engineering "intuition."
John
Date | Sujet | # | | Auteur |
1 Oct 24 | Re: Whether something is RISC or not (Re: PDP-8 theology, not Concertina II Progress) | 387 | | MitchAlsup1 |
1 Oct 24 |  Re: Whether something is RISC or not (Re: PDP-8 theology, not Concertina II Progress) | 386 | | Thomas Koenig |
1 Oct 24 |   Re: Whether something is RISC or not (Re: PDP-8 theology, not Concertina II Progress) | 379 | | MitchAlsup1 |
2 Oct 24 |    Re: Whether something is RISC or not (Re: PDP-8 theology, not Concertina II Progress) | 377 | | Brett |
3 Oct 24 |     Re: Whether something is RISC or not (Re: PDP-8 theology, not Concertina II Progress) | 376 | | Lawrence D'Oliveiro |
3 Oct 24 |      Re: Whether something is RISC or not (Re: PDP-8 theology, not Concertina II Progress) | 1 | | Brett |
3 Oct 24 |      Re: Whether something is RISC or not (Re: PDP-8 theology, not Concertina II Progress) | 1 | | Anton Ertl |
3 Oct 24 |      Re: Whether something is RISC or not (Re: PDP-8 theology, not Concertina II Progress) | 373 | | David Brown |
3 Oct 24 |       Byte ordering (was: Whether something is RISC or not) | 372 | | Anton Ertl |
3 Oct 24 |        Re: Byte ordering (was: Whether something is RISC or not) | 1 | | David Brown |
3 Oct 24 |        Re: Byte ordering (was: Whether something is RISC or not) | 369 | | Lawrence D'Oliveiro |
4 Oct 24 |         Re: Byte ordering | 1 | | Lynn Wheeler |
4 Oct 24 |         Re: Byte ordering (was: Whether something is RISC or not) | 365 | | David Brown |
4 Oct 24 |          Re: Byte ordering (was: Whether something is RISC or not) | 364 | | Anton Ertl |
4 Oct 24 |           Re: Byte ordering | 5 | | BGB |
5 Oct 24 |            Re: Byte ordering | 4 | | MitchAlsup1 |
5 Oct 24 |             Re: Byte ordering | 2 | | BGB |
5 Oct 24 |              Re: Byte ordering | 1 | | Lawrence D'Oliveiro |
5 Oct 24 |             Re: Byte ordering | 1 | | Lawrence D'Oliveiro |
5 Oct 24 |           Re: Byte ordering (was: Whether something is RISC or not) | 13 | | Lawrence D'Oliveiro |
5 Oct 24 |            Re: Byte ordering (was: Whether something is RISC or not) | 12 | | Brett |
5 Oct 24 |             Re: Byte ordering (was: Whether something is RISC or not) | 11 | | Anton Ertl |
5 Oct 24 |              Re: Byte ordering (was: Whether something is RISC or not) | 10 | | Michael S |
6 Oct 24 |               Re: Byte ordering | 1 | | Terje Mathisen |
6 Oct 24 |               Re: Byte ordering (was: Whether something is RISC or not) | 8 | | Brett |
7 Oct 24 |                Re: Byte ordering (was: Whether something is RISC or not) | 7 | | Lawrence D'Oliveiro |
7 Oct 24 |                 Re: Byte ordering (was: Whether something is RISC or not) | 6 | | Brett |
7 Oct 24 |                  Re: Byte ordering (was: Whether something is RISC or not) | 5 | | Michael S |
7 Oct 24 |                   Re: Byte ordering | 2 | | Stefan Monnier |
7 Oct 24 |                    Re: Byte ordering | 1 | | Michael S |
7 Oct 24 |                   Re: Byte ordering (was: Whether something is RISC or not) | 2 | | Lawrence D'Oliveiro |
8 Oct 24 |                    Re: Byte ordering | 1 | | Terje Mathisen |
6 Oct 24 |           Re: Byte ordering | 345 | | David Brown |
6 Oct 24 |            Re: Byte ordering | 344 | | Anton Ertl |
6 Oct 24 |             Re: Byte ordering | 189 | | John Dallman |
7 Oct 24 |              Re: Byte ordering | 20 | | Lawrence D'Oliveiro |
8 Oct 24 |               Re: Byte ordering | 19 | | John Dallman |
9 Oct 24 |                VMS/NT memory management (was: Byte ordering) | 1 | | Stefan Monnier |
15 Oct 24 |                Re: Byte ordering | 2 | | Lawrence D'Oliveiro |
15 Oct 24 |                 Re: Byte ordering | 1 | | MitchAlsup1 |
15 Oct 24 |                Re: Byte ordering | 15 | | Lawrence D'Oliveiro |
15 Oct 24 |                 Re: Byte ordering | 3 | | Michael S |
15 Oct 24 |                  Re: Byte ordering | 1 | | John Dallman |
18 Oct 24 |                  Re: Byte ordering | 1 | | Lawrence D'Oliveiro |
15 Oct 24 |                 Re: Byte ordering | 9 | | John Dallman |
16 Oct 24 |                  Re: Byte ordering | 7 | | George Neuner |
16 Oct 24 |                   Re: Byte ordering | 6 | | Terje Mathisen |
16 Oct 24 |                    Re: Byte ordering | 5 | | David Brown |
17 Oct 24 |                     Re: Byte ordering | 2 | | George Neuner |
17 Oct 24 |                      Re: Byte ordering | 1 | | David Brown |
17 Oct 24 |                     Re: clouds, not Byte ordering | 2 | | John Levine |
17 Oct 24 |                      Re: clouds, not Byte ordering | 1 | | David Brown |
18 Oct 24 |                  Re: Byte ordering | 1 | | Lawrence D'Oliveiro |
16 Oct 24 |                 Re: Byte ordering | 2 | | Paul A. Clayton |
18 Oct 24 |                  Re: Microkernels & Capabilities (was Re: Byte ordering) | 1 | | Lawrence D'Oliveiro |
7 Oct 24 |              80286 protected mode | 168 | | Anton Ertl |
7 Oct 24 |               Re: 80286 protected mode | 5 | | Lars Poulsen |
7 Oct 24 |                Re: 80286 protected mode | 4 | | Terje Mathisen |
7 Oct 24 |                 Re: 80286 protected mode | 1 | | Michael S |
7 Oct 24 |                 Re: 80286 protected mode | 2 | | Lawrence D'Oliveiro |
8 Oct 24 |                  Re: 80286 protected mode | 1 | | Terje Mathisen |
7 Oct 24 |               Re: 80286 protected mode | 3 | | Brett |
7 Oct 24 |                Re: 80286 protected mode | 2 | | Michael S |
7 Oct 24 |                 Re: 80286 protected mode | 1 | | Brett |
7 Oct 24 |               Re: 80286 protected mode | 1 | | Lawrence D'Oliveiro |
8 Oct 24 |               Re: 80286 protected mode | 152 | | MitchAlsup1 |
8 Oct 24 |                Re: 80286 protected mode | 4 | | Lawrence D'Oliveiro |
8 Oct 24 |                 Re: 80286 protected mode | 3 | | MitchAlsup1 |
9 Oct 24 |                  Re: 80286 protected mode | 1 | | David Brown |
15 Oct 24 |                  Re: 80286 protected mode | 1 | | Lawrence D'Oliveiro |
8 Oct 24 |                Re: 80286 protected mode | 147 | | Anton Ertl |
8 Oct 24 |                 Re: 80286 protected mode | 1 | | Robert Finch |
9 Oct 24 |                 Re: 80286 protected mode | 145 | | David Brown |
9 Oct 24 |                  Re: 80286 protected mode | 79 | | MitchAlsup1 |
9 Oct 24 |                   Re: 80286 protected mode | 78 | | David Brown |
9 Oct 24 |                    Re: 80286 protected mode | 77 | | Stephen Fuld |
10 Oct 24 |                     Re: 80286 protected mode | 2 | | MitchAlsup1 |
10 Oct 24 |                      Re: 80286 protected mode | 1 | | David Brown |
10 Oct 24 |                     Re: 80286 protected mode | 1 | | David Brown |
11 Oct 24 |                     Re: 80286 protected mode | 73 | | Tim Rentsch |
15 Oct 24 |                      Re: 80286 protected mode | 72 | | Stefan Monnier |
15 Oct 24 |                       Re: 80286 protected mode | 30 | | MitchAlsup1 |
16 Oct 24 |                        Re: 80286 protected mode | 25 | | MitchAlsup1 |
16 Oct 24 |                         Re: C and turtles, 80286 protected mode | 13 | | John Levine |
16 Oct 24 |                          Re: C and turtles, 80286 protected mode | 7 | | MitchAlsup1 |
16 Oct 24 |                           Re: C and turtles, 80286 protected mode | 6 | | John Levine |
17 Oct 24 |                            Re: C and turtles, 80286 protected mode | 5 | | Thomas Koenig |
20 Oct 24 |                             Re: C and turtles, 80286 protected mode | 4 | | Lawrence D'Oliveiro |
20 Oct 24 |                              Re: C and turtles, 80286 protected mode | 3 | | George Neuner |
22 Oct 24 |                               Re: C and turtles, 80286 protected mode | 2 | | Tim Rentsch |
22 Oct 24 |                                Re: C and turtles, 80286 protected mode | 1 | | George Neuner |
16 Oct 24 |                          Re: C and turtles, 80286 protected mode | 1 | | David Brown |
16 Oct 24 |                          Re: C and turtles, 80286 protected mode | 4 | | Paul A. Clayton |
17 Oct 24 |                           Re: C and turtles, 80286 protected mode | 1 | | David Brown |
20 Oct 24 |                           Re: C and turtles, 80286 protected mode | 2 | | Lawrence D'Oliveiro |
20 Oct 24 |                            Re: C and turtles, 80286 protected mode | 1 | | Paul A. Clayton |
16 Oct 24 |                         Re: 80286 protected mode | 7 | | Thomas Koenig |
16 Oct 24 |                          Re: 80286 protected mode | 2 | | MitchAlsup1 |
17 Oct 24 |                           Re: 80286 protected mode | 1 | | Tim Rentsch |
17 Oct 24 |                          Re: 80286 protected mode | 4 | | Tim Rentsch |
17 Oct 24 |                           Re: fine points of dynamic memory allocation, not 80286 protected mode | 3 | | John Levine |
17 Oct 24 |                         Re: 80286 protected mode | 3 | | George Neuner |
17 Oct 24 |                         Re: 80286 protected mode | 1 | | Tim Rentsch |
16 Oct 24 |                        Re: 80286 protected mode | 3 | | David Brown |
17 Oct 24 |                        Re: 80286 protected mode | 1 | | Tim Rentsch |
16 Oct 24 |                       Re: 80286 protected mode | 41 | | David Brown |
9 Oct 24 |                  Re: 80286 protected mode | 51 | | Thomas Koenig |
13 Oct 24 |                  Re: 80286 protected mode | 14 | | Anton Ertl |
8 Oct 24 |               Re: 80286 protected mode | 6 | | John Levine |
3 Jan 25 |             Re: Byte ordering | 154 | | Waldek Hebisch |
6 Oct 24 |         Re: Byte ordering (was: Whether something is RISC or not) | 2 | | Michael S |
3 Oct 24 |        Re: Byte ordering (was: Whether something is RISC or not) | 1 | | John Dallman |
2 Oct 24 |    Re: Whether something is RISC or not (Re: PDP-8 theology, not Concertina II Progress) | 1 | | Thomas Koenig |
2 Oct 24 |   Re: Whether something is RISC or not (Re: PDP-8 theology, not Concertina II Progress) | 5 | | David Schultz |
3 Oct 24 |   Re: Whether something is RISC or not (Re: PDP-8 theology, not Concertina II Progress) | 1 | | Lawrence D'Oliveiro |