Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.arch > #113595 > unrolled thread

Linus Torvalds on bad architectural features

Started byanton@mips.complang.tuwien.ac.at (Anton Ertl)
First post2025-10-03 08:58 +0000
Last post2025-12-28 21:34 +0000
Articles 20 on this page of 215 — 26 participants

Back to article view | Back to comp.arch


Contents

  Linus Torvalds on bad architectural features anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-10-03 08:58 +0000
    Re: Linus Torvalds on bad architectural features BGB <cr88192@gmail.com> - 2025-10-03 05:40 -0500
    Re: Linus Torvalds on bad architectural features Michael S <already5chosen@yahoo.com> - 2025-10-03 13:46 +0300
      SASOS and virtually tagged caches (was: Linus Torvalds on bad architectural features) Stefan Monnier <monnier@iro.umontreal.ca> - 2025-10-03 11:26 -0400
        Re: SASOS and virtually tagged caches (was: Linus Torvalds on bad architectural features) MitchAlsup <user5857@newsgrouper.org.invalid> - 2025-10-03 15:42 +0000
          Re: SASOS and virtually tagged caches (was: Linus Torvalds on bad architectural features) kegs@provalid.com (Kent Dickey) - 2025-10-03 16:18 +0000
            Re: SASOS and virtually tagged caches Stefan Monnier <monnier@iro.umontreal.ca> - 2025-10-03 15:44 -0400
            Re: SASOS and virtually tagged caches (was: Linus Torvalds on bad architectural features) George Neuner <gneuner2@comcast.net> - 2025-10-06 06:54 -0400
              Re: SASOS and virtually tagged caches (was: Linus Torvalds on bad architectural features) kegs@provalid.com (Kent Dickey) - 2025-10-06 16:44 +0000
        Re: SASOS and virtually tagged caches BGB <cr88192@gmail.com> - 2025-10-03 17:42 -0500
        Re: SASOS and virtually tagged caches (was: Linus Torvalds on bad architectural features) kegs@provalid.com (Kent Dickey) - 2025-10-04 04:36 +0000
          Re: SASOS and virtually tagged caches (was: Linus Torvalds on bad architectural features) John Levine <johnl@taugh.com> - 2025-10-04 18:36 +0000
            Re: SASOS and virtually tagged caches (was: Linus Torvalds on bad architectural features) Thomas Koenig <tkoenig@netcologne.de> - 2025-10-04 19:00 +0000
            Re: SASOS and virtually tagged caches Stephen Fuld <sfuld@alumni.cmu.edu.invalid> - 2025-10-04 12:31 -0700
            Re: SASOS and virtually tagged caches (was: Linus Torvalds on bad architectural features) Michael S <already5chosen@yahoo.com> - 2025-10-05 01:05 +0300
              Re: SASOS and virtually tagged caches (was: Linus Torvalds on bad architectural features) John Levine <johnl@taugh.com> - 2025-10-04 22:44 +0000
                Re: SASOS and virtually tagged caches BGB <cr88192@gmail.com> - 2025-10-04 17:57 -0500
                Re: SASOS and virtually tagged caches (was: Linus Torvalds on bad architectural features) Michael S <already5chosen@yahoo.com> - 2025-10-05 02:18 +0300
                Re: SASOS and virtually tagged caches EricP <ThatWouldBeTelling@thevillage.com> - 2025-10-05 13:02 -0400
            Re: SASOS and virtually tagged caches Lynn Wheeler <lynn@garlic.com> - 2025-10-04 14:17 -1000
            Re: SASOS and virtually tagged caches (was: Linus Torvalds on bad architectural features) kegs@provalid.com (Kent Dickey) - 2025-10-06 15:49 +0000
    Re: Linus Torvalds on bad architectural features MitchAlsup <user5857@newsgrouper.org.invalid> - 2025-10-03 15:41 +0000
      Re: Linus Torvalds on bad architectural features BGB <cr88192@gmail.com> - 2025-10-03 16:19 -0500
    Re: Linus Torvalds on bad architectural features John Savard <quadibloc@invalid.invalid> - 2025-10-09 13:57 +0000
    Re: Linus Torvalds on bad architectural features John Savard <quadibloc@invalid.invalid> - 2025-10-09 21:41 +0000
      Re: Linus Torvalds on bad architectural features MitchAlsup <user5857@newsgrouper.org.invalid> - 2025-10-09 22:10 +0000
      Re: Linus Torvalds on bad architectural features scott@slp53.sl.home (Scott Lurndal) - 2025-10-09 22:21 +0000
        Re: Linus Torvalds on bad architectural features anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-10-10 08:30 +0000
          Re: Linus Torvalds on bad architectural features scott@slp53.sl.home (Scott Lurndal) - 2025-10-10 15:02 +0000
      Re: Linus Torvalds on bad architectural features anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-10-11 07:18 +0000
        Re: Linus Torvalds on bad architectural features John Levine <johnl@taugh.com> - 2025-10-12 02:37 +0000
          Re: Linus Torvalds on bad architectural features Thomas Koenig <tkoenig@netcologne.de> - 2025-10-12 07:13 +0000
            Re: Linus Torvalds on bad architectural features anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-10-12 09:51 +0000
              Re: Linus Torvalds on bad architectural features Thomas Koenig <tkoenig@netcologne.de> - 2025-10-12 10:14 +0000
                Re: Linus Torvalds on bad architectural features Michael S <already5chosen@yahoo.com> - 2025-10-12 13:56 +0300
                  Re: Linus Torvalds on bad architectural features Thomas Koenig <tkoenig@netcologne.de> - 2025-10-12 11:38 +0000
                    Re: Linus Torvalds on bad architectural features Michael S <already5chosen@yahoo.com> - 2025-10-12 15:31 +0300
                      Re: Linus Torvalds on bad architectural features anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-10-12 13:36 +0000
                        Re: Linus Torvalds on bad architectural features Michael S <already5chosen@yahoo.com> - 2025-10-12 20:13 +0300
                          Re: Linus Torvalds on bad architectural features anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-10-12 17:47 +0000
                          Re: Linus Torvalds on bad architectural features MitchAlsup <user5857@newsgrouper.org.invalid> - 2025-10-12 19:31 +0000
                Re: Linus Torvalds on bad architectural features anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-10-12 13:31 +0000
                  Re: Linus Torvalds on bad architectural features Thomas Koenig <tkoenig@netcologne.de> - 2025-10-12 15:10 +0000
                    Re: Linus Torvalds on bad architectural features anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-10-12 15:48 +0000
                      Re: Linus Torvalds on bad architectural features Thomas Koenig <tkoenig@netcologne.de> - 2025-10-12 16:25 +0000
                        Re: Linus Torvalds on bad architectural features anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-10-12 17:25 +0000
                          Re: Linus Torvalds on bad architectural features Thomas Koenig <tkoenig@netcologne.de> - 2025-10-12 20:03 +0000
                            Re: Linus Torvalds on bad architectural features anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-10-12 21:07 +0000
                              Re: Linus Torvalds on bad architectural features Robert Swindells <rjs@fdy2.co.uk> - 2025-10-13 17:26 +0000
                    Re: Linus Torvalds on bad architectural features Michael S <already5chosen@yahoo.com> - 2025-10-12 19:56 +0300
                      Re: Linus Torvalds on bad architectural features Thomas Koenig <tkoenig@netcologne.de> - 2025-10-12 17:02 +0000
            Re: Linus Torvalds on bad architectural features John Levine <johnl@taugh.com> - 2025-10-12 21:07 +0000
          Re: Linus Torvalds on bad architectural features MitchAlsup <user5857@newsgrouper.org.invalid> - 2025-10-12 16:11 +0000
            Re: Linus Torvalds on bad architectural features BGB <cr88192@gmail.com> - 2025-10-12 13:04 -0500
            Re: Linus Torvalds on bad architectural features Lawrence D’Oliveiro <ldo@nz.invalid> - 2025-12-28 00:10 +0000
              Re: Linus Torvalds on bad architectural features MitchAlsup <user5857@newsgrouper.org.invalid> - 2025-12-28 17:43 +0000
                Re: Linus Torvalds on bad architectural features EricP <ThatWouldBeTelling@thevillage.com> - 2025-12-28 13:34 -0500
                Re: Linus Torvalds on bad architectural features Stefan Monnier <monnier@iro.umontreal.ca> - 2025-12-28 13:55 -0500
                  Re: Linus Torvalds on bad architectural features BGB <cr88192@gmail.com> - 2025-12-28 16:09 -0600
                    Re: Linus Torvalds on bad architectural features Thomas Koenig <tkoenig@netcologne.de> - 2025-12-28 23:00 +0000
                    Re: Linus Torvalds on bad architectural features anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-12-29 06:59 +0000
                      Re: Linus Torvalds on bad architectural features Thomas Koenig <tkoenig@netcologne.de> - 2025-12-29 08:17 +0000
                        word order and byte order (was: Linus Torvalds ...) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2025-12-29 09:08 +0000
                          Re: word order and byte order (was: Linus Torvalds ...) Thomas Koenig <tkoenig@netcologne.de> - 2025-12-29 13:39 +0000
                            Re: word order and byte order (was: Linus Torvalds ...) John Levine <johnl@taugh.com> - 2025-12-31 02:54 +0000
                              Re: word order and byte order (was: Linus Torvalds ...) Thomas Koenig <tkoenig@netcologne.de> - 2025-12-31 09:43 +0000
                                Re: floating point history, word order and byte order (was: Linus Torvalds ...) John Levine <johnl@taugh.com> - 2026-01-01 17:46 +0000
                                  Re: floating point history, word order and byte order (was: Linus Torvalds ...) Thomas Koenig <tkoenig@netcologne.de> - 2026-01-04 00:21 +0000
                                    Re: floating point history, word order and byte order (was: Linus Torvalds ...) John Levine <johnl@taugh.com> - 2026-01-04 04:12 +0000
                                      Re: floating point history, word order and byte order (was: Linus Torvalds ...) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-01-04 08:06 +0000
                                        Re: floating point history, word order and byte order (was: Linus Torvalds ...) Michael S <already5chosen@yahoo.com> - 2026-01-04 12:20 +0200
                                          Re: floating point history, word order and byte order (was: Linus Torvalds ...) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-01-04 18:01 +0000
                                            Re: floating point history, word order and byte order Stephen Fuld <sfuld@alumni.cmu.edu.invalid> - 2026-01-04 15:20 -0800
                                              Re: floating point history, word order and byte order anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-01-05 09:08 +0000
                                                Re: floating point history, word order and byte order jgd@cix.co.uk (John Dallman) - 2026-01-06 22:06 +0000
                                                  Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-07 13:34 +0200
                                                    Re: floating point history, word order and byte order jgd@cix.co.uk (John Dallman) - 2026-01-07 13:16 +0000
                                                      Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-07 17:55 +0200
                                                        Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-07 17:39 +0000
                                                      Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-07 18:58 +0100
                                                        Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-07 20:05 +0000
                                                          Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-07 23:47 +0200
                                                            Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-07 22:10 +0000
                                                              Re: floating point history, word order and byte order antispam@fricas.org (Waldek Hebisch) - 2026-01-11 00:59 +0000
                                                      Re: floating point history, word order and byte order BGB <cr88192@gmail.com> - 2026-01-07 14:23 -0600
                                                        Re: floating point history, word order and byte order Robert Finch <robfi680@gmail.com> - 2026-01-07 21:16 -0500
                                                      Re: floating point history, word order and byte order kegs@provalid.com (Kent Dickey) - 2026-01-28 13:25 +0000
                                                        Re: floating point history, word order and byte order BGB <cr88192@gmail.com> - 2026-01-28 15:26 -0600
                                                          Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-28 23:03 +0000
                                                            Re: floating point history, word order and byte order BGB <cr88192@gmail.com> - 2026-01-28 17:43 -0600
                                                              Re: floating point history, word order and byte order Robert Finch <robfi680@gmail.com> - 2026-01-29 03:47 -0500
                                                                Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-29 21:30 +0000
                                                                Re: floating point history, word order and byte order BGB <cr88192@gmail.com> - 2026-01-29 17:44 -0600
                                                    Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-07 18:56 +0100
                                                      Re: floating point history, word order and byte order BGB <cr88192@gmail.com> - 2026-01-07 14:38 -0600
                                                        Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-07 21:18 +0000
                                                          Re: floating point history, word order and byte order BGB <cr88192@gmail.com> - 2026-01-07 16:10 -0600
                                                            Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-08 00:05 +0000
                                                              Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-08 02:38 +0000
                                                                Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-08 10:52 +0200
                                                                  Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-08 18:50 +0000
                                                                Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-08 13:10 +0100
                                                                  Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-08 18:54 +0000
                                                                    Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-08 21:35 +0100
                                                                      Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-09 01:24 +0000
                                                                        Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-10 18:02 +0100
                                                                      Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-11 15:01 +0200
                                                                        Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-11 18:18 +0000
                                                                          Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-11 20:50 +0200
                                                                            Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-11 22:11 +0000
                                                                              Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-12 12:20 +0200
                                                                          Re: floating point history, word order and byte order Stefan Monnier <monnier@iro.umontreal.ca> - 2026-01-13 14:45 -0500
                                                                            Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-21 01:44 +0000
                                                                              Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-21 11:05 +0200
                                                                                Re: floating point history, word order and byte order Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-02-14 20:49 -0800
                                                                              Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-21 22:33 +0100
                                                                                Re: floating point history, word order and byte order Robert Finch <robfi680@gmail.com> - 2026-01-22 14:37 -0500
                                                                              Re: floating point history, word order and byte order George Neuner <gneuner2@comcast.net> - 2026-01-22 15:12 -0500
                                                                                Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-22 22:57 +0200
                                                                                  Re: floating point history, word order and byte order George Neuner <gneuner2@comcast.net> - 2026-01-23 13:47 -0500
                                                                                    [OT] Usenet (was: floating point history ...) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-01-24 15:58 +0000
                                                                                      Re: [OT] Usenet (was: floating point history ...) David LaRue <huey.dll@tampabay.rr.com> - 2026-01-25 01:09 +0000
                                                                                      Re: [OT] Usenet (was: floating point history ...) George Neuner <gneuner2@comcast.net> - 2026-01-25 18:12 -0500
                                                                                        Re: [OT] Usenet (was: floating point history ...) scott@slp53.sl.home (Scott Lurndal) - 2026-01-26 21:38 +0000
                                                                                          Re: [OT] Usenet Anssi Saari <anssi.saari@usenet.mail.kapsi.fi> - 2026-01-27 12:19 +0200
                                                                                          Re: [OT] Usenet (was: floating point history ...) George Neuner <gneuner2@comcast.net> - 2026-01-27 06:33 -0500
                                                                              Re: floating point history, word order and byte order jgd@cix.co.uk (John Dallman) - 2026-01-24 09:11 +0000
                                                                              Re: floating point history, word order and byte order Brett <ggtgp@yahoo.com> - 2026-01-25 22:13 +0000
                                                                        Re: floating point history, word order and byte order antispam@fricas.org (Waldek Hebisch) - 2026-01-11 22:30 +0000
                                                                          Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-12 01:07 +0200
                                                                          Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-12 01:10 +0200
                                                                          Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-12 00:57 +0200
                                                                    Re: floating point history, word order and byte order antispam@fricas.org (Waldek Hebisch) - 2026-01-11 01:14 +0000
                                                                      Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-11 12:52 +0100
                                                                      Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-11 18:07 +0000
                                                                        Re: floating point history, word order and byte order "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-01-11 12:40 -0800
                                                                          Re: floating point history, word order and byte order "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-01-11 15:41 -0800
                                                                          Re: floating point history, word order and byte order "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-01-11 15:40 -0800
                                                          Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-08 13:05 +0100
                                                    Re: floating point history, word order and byte order antispam@fricas.org (Waldek Hebisch) - 2026-01-11 00:33 +0000
                                                      Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-11 14:31 +0200
                                                  Re: floating point history, word order and byte order antispam@fricas.org (Waldek Hebisch) - 2026-01-10 23:21 +0000
                                                    Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-11 00:03 +0000
                                                      Re: floating point history, word order and byte order antispam@fricas.org (Waldek Hebisch) - 2026-01-11 11:21 +0000
                                                        Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-11 18:08 +0000
                                                    Re: floating point history, word order and byte order Stephen Fuld <sfuld@alumni.cmu.edu.invalid> - 2026-01-11 08:38 -0800
                                                      Re: floating point history, word order and byte order John Levine <johnl@taugh.com> - 2026-01-11 19:03 +0000
                                                        Re: floating point history, word order and byte order Thomas Koenig <tkoenig@netcologne.de> - 2026-01-12 22:22 +0000
                                                        Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-13 09:55 +0100
                                        Re: floating point history, word order and byte order (was: Linus Torvalds ...) MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-04 18:47 +0000
                                          Re: floating point history, word order and byte order Stefan Monnier <monnier@iro.umontreal.ca> - 2026-01-04 14:12 -0500
                                            Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-04 20:14 +0000
                                              Re: floating point history, word order and byte order Stephen Fuld <sfuld@alumni.cmu.edu.invalid> - 2026-01-04 13:05 -0800
                                              Re: floating point history, word order and byte order anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-01-05 08:51 +0000
                                                Re: floating point history, word order and byte order Stefan Monnier <monnier@iro.umontreal.ca> - 2026-01-05 11:55 -0500
                                                  Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-05 19:26 +0200
                                                    Re: floating point history, word order and byte order Stefan Monnier <monnier@iro.umontreal.ca> - 2026-01-05 14:33 -0500
                                                      Re: floating point history, word order and byte order anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-01-06 17:26 +0000
                                                  Re: floating point history, word order and byte order anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-01-05 17:40 +0000
                                                  Re: floating point history, word order and byte order antispam@fricas.org (Waldek Hebisch) - 2026-01-07 17:57 +0000
                                                    Re: floating point history, word order and byte order Thomas Koenig <tkoenig@netcologne.de> - 2026-01-09 16:32 +0000
                                                      Re: floating point history, word order and byte order antispam@fricas.org (Waldek Hebisch) - 2026-01-11 11:49 +0000
                                                        Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-11 18:11 +0000
                                                          Re: floating point history, word order and byte order antispam@fricas.org (Waldek Hebisch) - 2026-01-12 00:37 +0000
                                                            Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-12 02:05 +0000
                                                          Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-12 16:28 +0100
                                          Re: floating point history, word order and byte order (was: Linus Torvalds ...) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-01-05 08:16 +0000
                                            Re: floating point history, word order and byte order (was: Linus Torvalds ...) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-01-05 10:21 +0000
                                              Re: floating point history, word order and byte order EricP <ThatWouldBeTelling@thevillage.com> - 2026-01-05 11:05 -0500
                                                Re: floating point history, word order and byte order anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-01-05 18:03 +0000
                                                  Re: floating point history, word order and byte order EricP <ThatWouldBeTelling@thevillage.com> - 2026-01-05 13:51 -0500
                                                    Re: floating point history, word order and byte order EricP <ThatWouldBeTelling@thevillage.com> - 2026-01-05 14:21 -0500
                                                      Re: floating point history, word order and byte order anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-01-06 17:50 +0000
                                            Re: floating point history, word order and byte order EricP <ThatWouldBeTelling@thevillage.com> - 2026-01-05 10:31 -0500
                                              Re: floating point history, word order and byte order EricP <ThatWouldBeTelling@thevillage.com> - 2026-01-05 11:02 -0500
                                                Re: floating point history, word order and byte order anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-01-06 18:14 +0000
                                        Re: floating point history, word order and byte order (was: Linus Torvalds ...) scott@slp53.sl.home (Scott Lurndal) - 2026-01-05 15:40 +0000
                                      Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-04 13:22 +0100
                                    Re: floating point history, word order and byte order (was: Linus Torvalds ...) Michael S <already5chosen@yahoo.com> - 2026-01-04 12:36 +0200
                                      Re: floating point history, word order and byte order (was: Linus Torvalds ...) Thomas Koenig <tkoenig@netcologne.de> - 2026-01-04 16:45 +0000
                                        Re: floating point history, word order and byte order (was: Linus Torvalds ...) Michael S <already5chosen@yahoo.com> - 2026-01-04 19:35 +0200
                                        Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-06 12:35 +0100
                                          Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-06 15:26 +0200
                                            Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-06 17:06 +0100
                                              Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-06 17:59 +0000
                                                Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-06 20:15 +0200
                                                  Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-06 19:35 +0000
                                                    Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-06 23:09 +0200
                                      Re: floating point history, word order and byte order (was: Linus Torvalds ...) MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-06 17:56 +0000
                                        Re: floating point history, word order and byte order (was: Linus Torvalds ...) Michael S <already5chosen@yahoo.com> - 2026-01-06 20:12 +0200
                                          Re: floating point history, word order and byte order (was: Linus Torvalds ...) MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-06 19:29 +0000
                                            Re: floating point history, word order and byte order (was: Linus Torvalds ...) Michael S <already5chosen@yahoo.com> - 2026-01-07 15:06 +0200
                                              Re: floating point history, word order and byte order (was: Linus Torvalds ...) scott@slp53.sl.home (Scott Lurndal) - 2026-01-07 15:24 +0000
                                                Re: floating point history, word order and byte order (was: Linus Torvalds ...) Michael S <already5chosen@yahoo.com> - 2026-01-07 18:06 +0200
                                                  Re: floating point history, word order and byte order (was: Linus Torvalds ...) scott@slp53.sl.home (Scott Lurndal) - 2026-01-07 16:41 +0000
                                                    Re: floating point history, word order and byte order antispam@fricas.org (Waldek Hebisch) - 2026-01-07 17:32 +0000
                                                      Re: floating point history, word order and byte order scott@slp53.sl.home (Scott Lurndal) - 2026-01-07 19:14 +0000
                                                      Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-08 12:50 +0100
                                                        Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-08 15:41 +0200
                                                          Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-08 21:25 +0100
                                                            Re: floating point history, word order and byte order Michael S <already5chosen@yahoo.com> - 2026-01-08 22:50 +0200
                                                  Re: floating point history, word order and byte order (was: Linus Torvalds ...) MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-07 17:44 +0000
                                              Re: floating point history, word order and byte order Stephen Fuld <sfuld@alumni.cmu.edu.invalid> - 2026-01-07 10:22 -0800
                                            Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-07 18:47 +0100
                                        Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-07 18:38 +0100
                                          Re: floating point history, word order and byte order anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-01-07 18:38 +0000
                                            Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-07 20:11 +0000
                                              Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-08 13:01 +0100
                                                Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-08 18:52 +0000
                                          Re: floating point history, word order and byte order scott@slp53.sl.home (Scott Lurndal) - 2026-01-07 19:19 +0000
                                          Re: floating point history, word order and byte order MitchAlsup <user5857@newsgrouper.org.invalid> - 2026-01-07 19:56 +0000
                                    Re: floating point history, word order and byte order Terje Mathisen <terje.mathisen@tmsw.no> - 2026-01-04 13:17 +0100
                    Re: Linus Torvalds on bad architectural features Stefan Monnier <monnier@iro.umontreal.ca> - 2025-12-29 13:48 -0500
              Re: Linus Torvalds on bad architectural features Bill Findlay <findlaybill@blueyonder.co.uk> - 2025-12-28 19:21 +0000
                Re: Linus Torvalds on bad architectural features MitchAlsup <user5857@newsgrouper.org.invalid> - 2025-12-28 21:34 +0000

Page 6 of 11 — ← Prev page 1 … 4 5 [6] 7 8 … 11  Next page →


#114701 — Re: floating point history, word order and byte order

FromMitchAlsup <user5857@newsgrouper.org.invalid>
Date2026-01-08 18:50 +0000
SubjectRe: floating point history, word order and byte order
Message-ID<1767898214-5857@newsgrouper.org>
In reply to#114693
Michael S <already5chosen@yahoo.com> posted:

> On Thu, 08 Jan 2026 02:38:57 GMT
> MitchAlsup <user5857@newsgrouper.org.invalid> wrote:
> 
> > MitchAlsup <user5857@newsgrouper.org.invalid> posted:
> > -------------------
> > > 
> > > My Transcendentals get to 1ULP when the multiplier tree is
> > > 59×59-bits {a bit more than ½ of the get 1ULP at 58×58}. I gave a
> > > lot of though to this {~1 year} before deciding that a "Do
> > > everything else" function unit was "overall" better than a couple
> > > of "near miss" FUs. So, IMUL comes in at 4 cycles, FMUL at 4
> > > cycles, FDIV at 17, SQRT at 22, and IDIV at 25. The fast IMUL makes
> > > up a lot for the "size" of the FU.  
> > 
> > I forgot to add that my transcendentals went from <just barely>
> > faithfully rounded 0.75ULP RMS to 5.002ULP RMS when the tree was
> > expanded.
> > 
> 
> Don't you mean '0.5002 ULP' ?
> 
Technically, and rounding that is not !EEE correct is at least 1 ULP.

[toc] | [prev] | [next] | [standalone]


#114697 — Re: floating point history, word order and byte order

FromTerje Mathisen <terje.mathisen@tmsw.no>
Date2026-01-08 13:10 +0100
SubjectRe: floating point history, word order and byte order
Message-ID<10jo6r6$1f1e9$3@dont-email.me>
In reply to#114691
MitchAlsup wrote:
> 
> MitchAlsup <user5857@newsgrouper.org.invalid> posted:
> -------------------
>>
>> My Transcendentals get to 1ULP when the multiplier tree is 59×59-bits
>> {a bit more than ½ of the get 1ULP at 58×58}. I gave a lot of though
>> to this {~1 year} before deciding that a "Do everything else" function
>> unit was "overall" better than a couple of "near miss" FUs. So, IMUL
>> comes in at 4 cycles, FMUL at 4 cycles, FDIV at 17, SQRT at 22, and
>> IDIV at 25. The fast IMUL makes up a lot for the "size" of the FU.
> 
> I forgot to add that my transcendentals went from <just barely>
> faithfully rounded 0.75ULP RMS to 5.002ULP RMS when the tree was
> expanded.

You obviously intended 0.5002 ulp, so you have about 11-13 guard bits to 
get the rounding correct?

Terje

-- 
- <Terje.Mathisen at tmsw.no>
"almost all programming can be viewed as an exercise in caching"

[toc] | [prev] | [next] | [standalone]


#114703 — Re: floating point history, word order and byte order

FromMitchAlsup <user5857@newsgrouper.org.invalid>
Date2026-01-08 18:54 +0000
SubjectRe: floating point history, word order and byte order
Message-ID<1767898480-5857@newsgrouper.org>
In reply to#114697
Terje Mathisen <terje.mathisen@tmsw.no> posted:

> MitchAlsup wrote:
> > 
> > MitchAlsup <user5857@newsgrouper.org.invalid> posted:
> > -------------------
> >>
> >> My Transcendentals get to 1ULP when the multiplier tree is 59×59-bits
> >> {a bit more than ½ of the get 1ULP at 58×58}. I gave a lot of though
> >> to this {~1 year} before deciding that a "Do everything else" function
> >> unit was "overall" better than a couple of "near miss" FUs. So, IMUL
> >> comes in at 4 cycles, FMUL at 4 cycles, FDIV at 17, SQRT at 22, and
> >> IDIV at 25. The fast IMUL makes up a lot for the "size" of the FU.
> > 
> > I forgot to add that my transcendentals went from <just barely>
> > faithfully rounded 0.75ULP RMS to 5.002ULP RMS when the tree was
> > expanded.
> 
> You obviously intended 0.5002 ulp, so you have about 11-13 guard bits to 
> get the rounding correct?

64-53 = 11 yes

But a single incorrect rounding is 1 ULP all by itself.
> 
> Terje
> 

[toc] | [prev] | [next] | [standalone]


#114705 — Re: floating point history, word order and byte order

FromTerje Mathisen <terje.mathisen@tmsw.no>
Date2026-01-08 21:35 +0100
SubjectRe: floating point history, word order and byte order
Message-ID<10jp4e5$1qr00$1@dont-email.me>
In reply to#114703
MitchAlsup wrote:
> 
> Terje Mathisen <terje.mathisen@tmsw.no> posted:
> 
>> MitchAlsup wrote:
>>>
>>> MitchAlsup <user5857@newsgrouper.org.invalid> posted:
>>> -------------------
>>>>
>>>> My Transcendentals get to 1ULP when the multiplier tree is 59×59-bits
>>>> {a bit more than ½ of the get 1ULP at 58×58}. I gave a lot of though
>>>> to this {~1 year} before deciding that a "Do everything else" function
>>>> unit was "overall" better than a couple of "near miss" FUs. So, IMUL
>>>> comes in at 4 cycles, FMUL at 4 cycles, FDIV at 17, SQRT at 22, and
>>>> IDIV at 25. The fast IMUL makes up a lot for the "size" of the FU.
>>>
>>> I forgot to add that my transcendentals went from <just barely>
>>> faithfully rounded 0.75ULP RMS to 5.002ULP RMS when the tree was
>>> expanded.
>>
>> You obviously intended 0.5002 ulp, so you have about 11-13 guard bits to
>> get the rounding correct?
> 
> 64-53 = 11 yes

For many of the functions you can do a lot by letting the final 
operation be a merging of the first/largest term, particularly if you do 
that with extended precision.

I.e something like fpatan2() works quite nicely this way, just not 
enough for exact rounding.

You need to combine this with extended precision range adjustment at the 
end.

> 
> But a single incorrect rounding is 1 ULP all by itself.

:-)

Yeah, there are strong forces who want to have, at least as a 
suggested/recommended option, a set of transcendental functions which 
are exactly rounded.

It is provably doable for float, in very close to the same cycle count 
as the best libraries in current use, double is "somewhat" harder to 
totally verify/prove.

Terje

-- 
- <Terje.Mathisen at tmsw.no>
"almost all programming can be viewed as an exercise in caching"

[toc] | [prev] | [next] | [standalone]


#114707 — Re: floating point history, word order and byte order

FromMitchAlsup <user5857@newsgrouper.org.invalid>
Date2026-01-09 01:24 +0000
SubjectRe: floating point history, word order and byte order
Message-ID<1767921857-5857@newsgrouper.org>
In reply to#114705
Terje Mathisen <terje.mathisen@tmsw.no> posted:

> MitchAlsup wrote:
> > 
> > Terje Mathisen <terje.mathisen@tmsw.no> posted:
> > 
> >> MitchAlsup wrote:
> >>>
> >>> MitchAlsup <user5857@newsgrouper.org.invalid> posted:
> >>> -------------------
> >>>>
> >>>> My Transcendentals get to 1ULP when the multiplier tree is 59×59-bits
> >>>> {a bit more than ½ of the get 1ULP at 58×58}. I gave a lot of though
> >>>> to this {~1 year} before deciding that a "Do everything else" function
> >>>> unit was "overall" better than a couple of "near miss" FUs. So, IMUL
> >>>> comes in at 4 cycles, FMUL at 4 cycles, FDIV at 17, SQRT at 22, and
> >>>> IDIV at 25. The fast IMUL makes up a lot for the "size" of the FU.
> >>>
> >>> I forgot to add that my transcendentals went from <just barely>
> >>> faithfully rounded 0.75ULP RMS to 5.002ULP RMS when the tree was
> >>> expanded.
> >>
> >> You obviously intended 0.5002 ulp, so you have about 11-13 guard bits to
> >> get the rounding correct?
> > 
> > 64-53 = 11 yes
> 
> For many of the functions you can do a lot by letting the final 
> operation be a merging of the first/largest term, particularly if you do 
> that with extended precision.
> 
> I.e something like fpatan2() works quite nicely this way, just not 
> enough for exact rounding.
> 
> You need to combine this with extended precision range adjustment at the 
> end.
> 
> > 
> > But a single incorrect rounding is 1 ULP all by itself.
> 
> :-)
> 
> Yeah, there are strong forces who want to have, at least as a 
> suggested/recommended option, a set of transcendental functions which 
> are exactly rounded.

After the final addition, I know 1 of the top 3-bits is a 1, and I
have 69-bits in the accumulated result. I also know that the poly-
nomial error is below the 3rd least significant bit.
 
> It is provably doable for float, in very close to the same cycle count 
> as the best libraries in current use, double is "somewhat" harder to 
> totally verify/prove.

I have logic (patented) that allows the FU to raise an UNCERTAIN
rounding exception, so SW can take over and change 0.5002 into
0.5000 at the cost of the exception and running the long winded
SW correctly rounded subroutine. I expect this to be used only
during verification and on the 3 machines owned by Kahan, Coonen,
and someone else I forgot.
 
> Terje
> 

[toc] | [prev] | [next] | [standalone]


#114713 — Re: floating point history, word order and byte order

FromTerje Mathisen <terje.mathisen@tmsw.no>
Date2026-01-10 18:02 +0100
SubjectRe: floating point history, word order and byte order
Message-ID<10ju0nm$3a92q$1@dont-email.me>
In reply to#114707
MitchAlsup wrote:
> 
> Terje Mathisen <terje.mathisen@tmsw.no> posted:
> 
>> MitchAlsup wrote:
>>> But a single incorrect rounding is 1 ULP all by itself.
>>
>> :-)
>>
>> Yeah, there are strong forces who want to have, at least as a
>> suggested/recommended option, a set of transcendental functions which
>> are exactly rounded.
> 
> After the final addition, I know 1 of the top 3-bits is a 1, and I
> have 69-bits in the accumulated result. I also know that the poly-
> nomial error is below the 3rd least significant bit.
>   
>> It is provably doable for float, in very close to the same cycle count
>> as the best libraries in current use, double is "somewhat" harder to
>> totally verify/prove.
> 
> I have logic (patented) that allows the FU to raise an UNCERTAIN
> rounding exception, so SW can take over and change 0.5002 into
> 0.5000 at the cost of the exception and running the long winded
> SW correctly rounded subroutine. I expect this to be used only
> during verification and on the 3 machines owned by Kahan, Coonen,
> and someone else I forgot.

<BG>

Terje


-- 
- <Terje.Mathisen at tmsw.no>
"almost all programming can be viewed as an exercise in caching"

[toc] | [prev] | [next] | [standalone]


#114723 — Re: floating point history, word order and byte order

FromMichael S <already5chosen@yahoo.com>
Date2026-01-11 15:01 +0200
SubjectRe: floating point history, word order and byte order
Message-ID<20260111150116.00000f04@yahoo.com>
In reply to#114705
On Thu, 8 Jan 2026 21:35:16 +0100
Terje Mathisen <terje.mathisen@tmsw.no> wrote:

> MitchAlsup wrote:
> > 
> > 
> > But a single incorrect rounding is 1 ULP all by itself.  
> 
> :-)
> 
> Yeah, there are strong forces who want to have, at least as a 
> suggested/recommended option, a set of transcendental functions which 
> are exactly rounded.
> 

I wonder who are those forces and what is the set they push for.

I would guess that they are mostly software and hardware verification
people rather than people that use transcendental functions in
engineering and physical calculations.

The majority of the latter crowd would likely have no objections
against 0.75 ULP RMS as long as implementation is both fast and
preserving few invariant, of which I can primarily think of two:

1. Evenness/odness
If precise function F(x) is even or odd then approximate functions f(x)
is also even or odd.

2. Weak preservation of sign of delta.
If F(x) < F(x+ULP) then f(x) <= f(x+ULP)
If F(x) > F(x+ULP) then f(x) >= f(x+ULP)


In practice, it's probably unlikely to have these invariant preserved
when RMS error is 0.75 ULP, but for RMS error = 0.60-0.65 ULP I don't
see difficulties.
For many transcendental functions there will be only few problematic
values of x near edges of implementation-specific ranges where one
has to be careful.

> It is provably doable for float, in very close to the same cycle
> count as the best libraries in current use, double is "somewhat"
> harder to totally verify/prove.
> 
> Terje
> 

[toc] | [prev] | [next] | [standalone]


#114728 — Re: floating point history, word order and byte order

FromMitchAlsup <user5857@newsgrouper.org.invalid>
Date2026-01-11 18:18 +0000
SubjectRe: floating point history, word order and byte order
Message-ID<1768155480-5857@newsgrouper.org>
In reply to#114723
Michael S <already5chosen@yahoo.com> posted:

> On Thu, 8 Jan 2026 21:35:16 +0100
> Terje Mathisen <terje.mathisen@tmsw.no> wrote:
> 
> > MitchAlsup wrote:
> > > 
> > > 
> > > But a single incorrect rounding is 1 ULP all by itself.  
> > 
> > :-)
> > 
> > Yeah, there are strong forces who want to have, at least as a 
> > suggested/recommended option, a set of transcendental functions which 
> > are exactly rounded.
> > 
> 
> I wonder who are those forces and what is the set they push for.

The problem, here, is that even when one gets all the rounding correct,
one has still lost various algebraic identities.

     CRSIN(x)^2 + CRCOS(X)^2 ~= 1.0
 
> I would guess that they are mostly software and hardware verification
> people rather than people that use transcendental functions in
> engineering and physical calculations.

Numerical people, almost never engineers, physicists, or chemists.
 
> The majority of the latter crowd would likely have no objections
> against 0.75 ULP RMS as long as implementation is both fast and
> preserving few invariant, of which I can primarily think of two:
> 
> 1. Evenness/odness
> If precise function F(x) is even or odd then approximate functions f(x)
> is also even or odd.

Odd functions need to be monotonic around zero.
 
> 2. Weak preservation of sign of delta.
> If F(x) < F(x+ULP) then f(x) <= f(x+ULP)
> If F(x) > F(x+ULP) then f(x) >= f(x+ULP)

Small scale Monotonicity.
 
> 
> In practice, it's probably unlikely to have these invariant preserved
> when RMS error is 0.75 ULP, but for RMS error = 0.60-0.65 ULP I don't
> see difficulties.
> For many transcendental functions there will be only few problematic
> values of x near edges of implementation-specific ranges where one
> has to be careful.
> 
> > It is provably doable for float, in very close to the same cycle
> > count as the best libraries in current use, double is "somewhat"
> > harder to totally verify/prove.
> > 
> > Terje
> > 
> 

[toc] | [prev] | [next] | [standalone]


#114729 — Re: floating point history, word order and byte order

FromMichael S <already5chosen@yahoo.com>
Date2026-01-11 20:50 +0200
SubjectRe: floating point history, word order and byte order
Message-ID<20260111205004.00002d9f@yahoo.com>
In reply to#114728
On Sun, 11 Jan 2026 18:18:00 GMT
MitchAlsup <user5857@newsgrouper.org.invalid> wrote:

> Michael S <already5chosen@yahoo.com> posted:
> 
> > On Thu, 8 Jan 2026 21:35:16 +0100
> > Terje Mathisen <terje.mathisen@tmsw.no> wrote:
> >   
> > > MitchAlsup wrote:  
> > > > 
> > > > 
> > > > But a single incorrect rounding is 1 ULP all by itself.    
> > > 
> > > :-)
> > > 
> > > Yeah, there are strong forces who want to have, at least as a 
> > > suggested/recommended option, a set of transcendental functions
> > > which are exactly rounded.
> > >   
> > 
> > I wonder who are those forces and what is the set they push for.  
> 
> The problem, here, is that even when one gets all the rounding
> correct, one has still lost various algebraic identities.
> 
>      CRSIN(x)^2 + CRCOS(X)^2 ~= 1.0
>  
> > I would guess that they are mostly software and hardware
> > verification people rather than people that use transcendental
> > functions in engineering and physical calculations.  
> 
> Numerical people, almost never engineers, physicists, or chemists.
>  
> > The majority of the latter crowd would likely have no objections
> > against 0.75 ULP RMS as long as implementation is both fast and
> > preserving few invariant, of which I can primarily think of two:
> > 
> > 1. Evenness/odness
> > If precise function F(x) is even or odd then approximate functions
> > f(x) is also even or odd.  
> 
> Odd functions need to be monotonic around zero.
>  
> > 2. Weak preservation of sign of delta.
> > If F(x) < F(x+ULP) then f(x) <= f(x+ULP)
> > If F(x) > F(x+ULP) then f(x) >= f(x+ULP)  
> 
> Small scale Monotonicity.
>  

Yes, that's a better name.
I just wanted to express it as simple non-equality conditions and made
it too simple and stronger than necessary.
In fact I would not complain if my conditions do not hold when F(x) has
extremum in between x and x+ULP. That is, it's nice if condition holds
here as well, but it is relatively less important than holding on
monotonous intervals.

> > 
> > In practice, it's probably unlikely to have these invariant
> > preserved when RMS error is 0.75 ULP, but for RMS error = 0.60-0.65
> > ULP I don't see difficulties.
> > For many transcendental functions there will be only few problematic
> > values of x near edges of implementation-specific ranges where one
> > has to be careful.
> >   
> > > It is provably doable for float, in very close to the same cycle
> > > count as the best libraries in current use, double is "somewhat"
> > > harder to totally verify/prove.
> > > 
> > > Terje
> > >   
> >   

[toc] | [prev] | [next] | [standalone]


#114732 — Re: floating point history, word order and byte order

FromMitchAlsup <user5857@newsgrouper.org.invalid>
Date2026-01-11 22:11 +0000
SubjectRe: floating point history, word order and byte order
Message-ID<1768169515-5857@newsgrouper.org>
In reply to#114729
Michael S <already5chosen@yahoo.com> posted:

> On Sun, 11 Jan 2026 18:18:00 GMT
> MitchAlsup <user5857@newsgrouper.org.invalid> wrote:
> 
> > Michael S <already5chosen@yahoo.com> posted:
> > 
> > > On Thu, 8 Jan 2026 21:35:16 +0100
> > > Terje Mathisen <terje.mathisen@tmsw.no> wrote:
> > >   
> > > > MitchAlsup wrote:  
> > > > > 
> > > > > 
> > > > > But a single incorrect rounding is 1 ULP all by itself.    
> > > > 
> > > > :-)
> > > > 
> > > > Yeah, there are strong forces who want to have, at least as a 
> > > > suggested/recommended option, a set of transcendental functions
> > > > which are exactly rounded.
> > > >   
> > > 
> > > I wonder who are those forces and what is the set they push for.  
> > 
> > The problem, here, is that even when one gets all the rounding
> > correct, one has still lost various algebraic identities.
> > 
> >      CRSIN(x)^2 + CRCOS(X)^2 ~= 1.0
> >  
> > > I would guess that they are mostly software and hardware
> > > verification people rather than people that use transcendental
> > > functions in engineering and physical calculations.  
> > 
> > Numerical people, almost never engineers, physicists, or chemists.
> >  
> > > The majority of the latter crowd would likely have no objections
> > > against 0.75 ULP RMS as long as implementation is both fast and
> > > preserving few invariant, of which I can primarily think of two:
> > > 
> > > 1. Evenness/odness
> > > If precise function F(x) is even or odd then approximate functions
> > > f(x) is also even or odd.  
> > 
> > Odd functions need to be monotonic around zero.
> >  
> > > 2. Weak preservation of sign of delta.
> > > If F(x) < F(x+ULP) then f(x) <= f(x+ULP)
> > > If F(x) > F(x+ULP) then f(x) >= f(x+ULP)  
> > 
> > Small scale Monotonicity.
> >  
> 
> Yes, that's a better name.
> I just wanted to express it as simple non-equality conditions and made
> it too simple and stronger than necessary.
> In fact I would not complain if my conditions do not hold when F(x) has
> extremum in between x and x+ULP. That is, it's nice if condition holds
> here as well, but it is relatively less important than holding on
> monotonous intervals.

Consider COS(x) near 0.0

The transition from 1.0 to .99999999 and later to 0.99999998 (in both
directions) is small scale monotonic. AND it is exactly at this trans-
ition where my rounding takes the biggest number of hits (incorrect
roundings).

Seen in binary, one has a prerounded result of:

0.1111111111 1111111111 1111111111 1111111111 1111111111 1111 and digits

behind where rounding transpires. If those digits start with 01111111111
or 1000000000 then we are in the situation where we cannot know if we can
choose a correct rounding; the next term of the polynomial could sway the
balance. J. M. Mueller chapter 11 shows that one might need as many as
2×n+13 bits in order to get the rounding "correct". This must include,
polynomial error, arithmetic error, and certain boundary conditions.

If rounding that begins 01 contains a second 0, correct rounding happens.
if rounding that begins 10 contains a second 1, correct rounding happens.

And it is exactly at these points that
a) while the result remains monotonic, the point of change can be "off"
   by a small number of Δs
b) when the slope is shallow, one can get several rounding errors in a row
   without loosing the property of monotonicity or overall RMS.

> 
> > > 
> > > In practice, it's probably unlikely to have these invariant
> > > preserved when RMS error is 0.75 ULP, but for RMS error = 0.60-0.65
> > > ULP I don't see difficulties.
> > > For many transcendental functions there will be only few problematic
> > > values of x near edges of implementation-specific ranges where one
> > > has to be careful.
> > >   
> > > > It is provably doable for float, in very close to the same cycle
> > > > count as the best libraries in current use, double is "somewhat"
> > > > harder to totally verify/prove.
> > > > 
> > > > Terje
> > > >   
> > >   
> 
> 

[toc] | [prev] | [next] | [standalone]


#114741 — Re: floating point history, word order and byte order

FromMichael S <already5chosen@yahoo.com>
Date2026-01-12 12:20 +0200
SubjectRe: floating point history, word order and byte order
Message-ID<20260112122048.000075da@yahoo.com>
In reply to#114732
On Sun, 11 Jan 2026 22:11:55 GMT
MitchAlsup <user5857@newsgrouper.org.invalid> wrote:
> 
> Consider COS(x) near 0.0
> 

sin/cos is not an interesting or hard case, because for sin/cos the
value at extremum is exactly 1 or -1, i.e. it is representable exactly
by any BFP format. Plus, slop is very shallow. It means that any sane
implementation of sin/cos will have no troubles correctly rounding both
sides of interval that contains extremum to 1 (or -1). At least it
holds as long as x is in the sane range (abs(x) < 2**26). For x outside
that range, you (i.e. engineer, chemist, phisicist) just know that you
are doing something very wrong, and implementation of trigs is among
last things that you should be concerned about.

More challenging cases are transcendental functions that have extrema
with values that are non-representable exactly, especially so when the
value is close to the mid-point between two representable numbers.

[toc] | [prev] | [next] | [standalone]


#114745 — Re: floating point history, word order and byte order

FromStefan Monnier <monnier@iro.umontreal.ca>
Date2026-01-13 14:45 -0500
SubjectRe: floating point history, word order and byte order
Message-ID<jwvjyxlwbx5.fsf-monnier+comp.arch@gnu.org>
In reply to#114728
MitchAlsup [2026-01-11 18:18:00] wrote:
> Michael S <already5chosen@yahoo.com> posted:
>> Terje Mathisen <terje.mathisen@tmsw.no> wrote:
>>> Yeah, there are strong forces who want to have, at least as a 
>>> suggested/recommended option, a set of transcendental functions which 
>>> are exactly rounded.
>> I wonder who are those forces and what is the set they push for.

One reason to want it comes from portability and bit-for-bit
reproducibility.  These requirements don't actually care about the
rounding being *correct* as much as the rounding always being the same
across different hardware and libm implementations, but it seems rather
unlikely that the various actors involved would agree on a particular
return value if it's not the correctly-rounded one, so in practice this
becomes a push for correctly rounded results.

> The problem, here, is that even when one gets all the rounding correct,
> one has still lost various algebraic identities.
>
>      CRSIN(x)^2 + CRCOS(X)^2 ~= 1.0

Which properties are preserved and which ones aren't is inevitably
a compromise since, for example, the above one cannot be preserved
without breaking several others.


- Stefan

[toc] | [prev] | [next] | [standalone]


#114746 — Re: floating point history, word order and byte order

FromMitchAlsup <user5857@newsgrouper.org.invalid>
Date2026-01-21 01:44 +0000
SubjectRe: floating point history, word order and byte order
Message-ID<1768959848-5857@newsgrouper.org>
In reply to#114745
Anyone still here and active ???

Mitch

[toc] | [prev] | [next] | [standalone]


#114747 — Re: floating point history, word order and byte order

FromMichael S <already5chosen@yahoo.com>
Date2026-01-21 11:05 +0200
SubjectRe: floating point history, word order and byte order
Message-ID<20260121110530.00001540@yahoo.com>
In reply to#114746
On Wed, 21 Jan 2026 01:44:08 GMT
MitchAlsup <user5857@newsgrouper.org.invalid> wrote:

> Anyone still here and active ???
> 
> Mitch

https://www.linfo.org/rule_of_silence.html

I have serious doubts about universality of wisdom of this rule in the
field of human-machine interfaces, but for Usenet interaction it is
golden.

[toc] | [prev] | [next] | [standalone]


#114978 — Re: floating point history, word order and byte order

FromTim Rentsch <tr.17687@z991.linuxsc.com>
Date2026-02-14 20:49 -0800
SubjectRe: floating point history, word order and byte order
Message-ID<86fr72hari.fsf@linuxsc.com>
In reply to#114747
Michael S <already5chosen@yahoo.com> writes:

> On Wed, 21 Jan 2026 01:44:08 GMT
> MitchAlsup <user5857@newsgrouper.org.invalid> wrote:
>
>> Anyone still here and active ???
>
> https://www.linfo.org/rule_of_silence.html
>
> I have serious doubts about universality of wisdom of this rule in the
> field of human-machine interfaces, but for Usenet interaction it is
> golden.

Thank you for this.

[toc] | [prev] | [next] | [standalone]


#114748 — Re: floating point history, word order and byte order

FromTerje Mathisen <terje.mathisen@tmsw.no>
Date2026-01-21 22:33 +0100
SubjectRe: floating point history, word order and byte order
Message-ID<10krgml$2fb90$1@dont-email.me>
In reply to#114746
MitchAlsup wrote:
> 
> Anyone still here and active ???
> 
> Mitch
> 
Yes!

-- 
- <Terje.Mathisen at tmsw.no>
"almost all programming can be viewed as an exercise in caching"

[toc] | [prev] | [next] | [standalone]


#114751 — Re: floating point history, word order and byte order

FromRobert Finch <robfi680@gmail.com>
Date2026-01-22 14:37 -0500
SubjectRe: floating point history, word order and byte order
Message-ID<10ktua6$39hjp$1@dont-email.me>
In reply to#114748
On 2026-01-21 4:33 p.m., Terje Mathisen wrote:
> MitchAlsup wrote:
>>
>> Anyone still here and active ???
>>
>> Mitch
>>
> Yes!
> 
Still here. I thought maybe the snow put a damper on things.

I have been working away on Q+4 doing simulation runs while waiting for 
posts on comp.arch. The timing goal has been bumped up to 100 MHz from 
40 MHz.

Been toying with a couple of ideas. One is to give the machine a wider 
or perhaps narrower datapath to support 80 or 96 bits operations. A few 
extra digits for finance. Do not really want to go to 128-bits. A 48-bit 
machine could have 96-bit double precision support. Another idea is to 
go six wide.

[toc] | [prev] | [next] | [standalone]


#114752 — Re: floating point history, word order and byte order

FromGeorge Neuner <gneuner2@comcast.net>
Date2026-01-22 15:12 -0500
SubjectRe: floating point history, word order and byte order
Message-ID<gs05nkhve77fqdd74a84voich0pneqh8gd@4ax.com>
In reply to#114746
On Wed, 21 Jan 2026 01:44:08 GMT, MitchAlsup
<user5857@newsgrouper.org.invalid> wrote:

>Anyone still here and active ???
>
>Mitch

Still here. 

Given that Usenet as a whole seems to be dying, sudden pauses in
postings are eerie.

[toc] | [prev] | [next] | [standalone]


#114753 — Re: floating point history, word order and byte order

FromMichael S <already5chosen@yahoo.com>
Date2026-01-22 22:57 +0200
SubjectRe: floating point history, word order and byte order
Message-ID<20260122225750.00002cb5@yahoo.com>
In reply to#114752
On Thu, 22 Jan 2026 15:12:06 -0500
George Neuner <gneuner2@comcast.net> wrote:

> On Wed, 21 Jan 2026 01:44:08 GMT, MitchAlsup
> <user5857@newsgrouper.org.invalid> wrote:
> 
> >Anyone still here and active ???
> >
> >Mitch  
> 
> Still here. 
> 
> Given that Usenet as a whole seems to be dying, sudden pauses in
> postings are eerie.

Usenet as a whole is dying for several years longer than the time since
I first discovered it 23+ years ago.

[toc] | [prev] | [next] | [standalone]


#114770 — Re: floating point history, word order and byte order

FromGeorge Neuner <gneuner2@comcast.net>
Date2026-01-23 13:47 -0500
SubjectRe: floating point history, word order and byte order
Message-ID<mad7nkhgpjjf7u6alnsjppmu3qo20dpca5@4ax.com>
In reply to#114753
On Thu, 22 Jan 2026 22:57:50 +0200, Michael S
<already5chosen@yahoo.com> wrote:

>On Thu, 22 Jan 2026 15:12:06 -0500
>George Neuner <gneuner2@comcast.net> wrote:
>
>> On Wed, 21 Jan 2026 01:44:08 GMT, MitchAlsup
>> <user5857@newsgrouper.org.invalid> wrote:
>> 
>> >Anyone still here and active ???
>> >
>> >Mitch  
>> 
>> Still here. 
>> 
>> Given that Usenet as a whole seems to be dying, sudden pauses in
>> postings are eerie.
>
>Usenet as a whole is dying for several years longer than the time since
>I first discovered it 23+ years ago.
>

I discovered Usenet in the late 80's. I participated in about 20 of
the comp.* and sci.* groups.  All through the 90's and even into the
early 00's many of them were quite lively.

I recognized early on that the file sharing groups were in trouble -
mainly due to legal issues - but I didn't get the sense that Usenet
was in decline more generally until the late 00's.

And it wasn't for lack of GUIs:  I can't recall names now, but there
were at least 2 different terminal hosted GUIs (one of which had a
Windows port), Netscape mail did NN natively, and AltaVista had a
quite nice [text but browser hosted] interface to Usenet.

Google managed to f_ up everything AltaVista did, Microsoft pushed
Netscape aside, Firefox came along but quickly removed its initial
email and NN support, Thunderbird and SeaMonkey took too long to
appear, and too many web providers were trying to cash in by luring
people to pay-walled forums.

It seems all it would have taken was one decent web site providing a
good user experience for Usenet.  

Yeah, I know ... why didn't I do it?  Well, I don't do web sites. 
[Actually, that's incorrect:  I do do middle and backend work, but I
don't do any user facing (GUI) stuff. I've been told my sense of what
is "easy to use" is somewhat stunted ... I've been in computing since
1980 and I am mostly satisfied that something works.  Moreover, I
don't consider very much "modern" software - and almost nothing that
runs on a phone or in a browser - to be particularly easy to use.]

YMMV.

[toc] | [prev] | [next] | [standalone]


Page 6 of 11 — ← Prev page 1 … 4 5 [6] 7 8 … 11  Next page →

Back to top | Article view | comp.arch


csiph-web