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| From | 88888 Dihedral <dihedral88888@googlemail.com> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: Performance of hand-optimised assembly |
| Date | 2011-12-24 04:56 -0800 |
| Organization | http://groups.google.com |
| Message-ID | <7012282.140.1324731402525.JavaMail.geo-discussion-forums@prix23> (permalink) |
| References | <0.d0ecd8f477637819bed2.20111223184332GMT.87pqffjfhn.fsf@bsb.me.uk> <slrnjfbig5.1lg9.willem@toad.stack.nl> |
On Saturday, December 24, 2011 8:48:05 PM UTC+8, Willem wrote: > Ben Bacarisse wrote: > ) I'm starting a new thread, but it is prompted by this remark from 88888 > ) Dihedral <dihedr...@googlemail.com> about a short binary search > ) function I posted: > ) > ) <snip> > ) On my laptop[1], gcc's optimiser (version 4.6.1) almost exactly halves the > ) times. clang's code is a little better at -O0, but the optimised code > ) is a little worse: > ) -O0 -O1 -O2 -O3 > ) gcc 0.1128 0.0633 0.0571 0.0562 > ) g++ 0.1167 0.0633 0.0572 0.0564 > ) clang 0.1033 0.0669 0.0672 0.0672 > ) > ) These times are microseconds per call. The loop overhead has been > ) subtracted[2]. > > Have you tried enabling the processor-specific switches on gcc? > > ) [1] Intel(R) Core(TM)2 Duo CPU P8700 @ 2.53GHz, 3MB cache > ) [2] Crude timing script available on request. > > SaSW, Willem > -- > Disclaimer: I am in no way responsible for any of the statements > made in the above text. For all I know I might be > drugged or something.. > No I'm not paranoid. You all think I'm paranoid, don't you ! > #EOT I think pass by register is faster. But if just insert 10 to 20 lines of assembly can make the code to be faster. I'll go for assembly to eliminate the function call overheads. By the way swapping two registers with or without a tmp register in 3 instructions is really hardware dependent.
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Performance of hand-optimised assembly Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-23 18:43 +0000
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2011-12-23 19:40 +0000
Re: Performance of hand-optimised assembly Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-23 21:26 +0000
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2011-12-23 22:02 +0000
Re: Performance of hand-optimised assembly Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-24 02:52 +0000
Re: Performance of hand-optimised assembly 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-23 20:32 -0800
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2011-12-24 13:09 +0000
Re: Performance of hand-optimised assembly James Harris <james.harris.1@googlemail.com> - 2011-12-24 05:49 -0800
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2011-12-24 15:30 +0000
Re: Performance of hand-optimised assembly James Harris <james.harris.1@googlemail.com> - 2011-12-24 08:15 -0800
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2011-12-24 17:10 +0000
Re: Performance of hand-optimised assembly Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-24 23:25 +0000
Re: Performance of hand-optimised assembly jgk@panix.com (Joe keane) - 2012-01-04 03:24 +0000
Re: Performance of hand-optimised assembly jacob navia <jacob@spamsink.net> - 2012-01-04 09:59 +0100
Re: Performance of hand-optimised assembly jgk@panix.com (Joe keane) - 2012-01-04 20:57 +0000
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2012-01-04 23:04 +0000
Re: Performance of hand-optimised assembly Noob <root@127.0.0.1> - 2012-01-05 13:32 +0100
Re: Performance of hand-optimised assembly Philip Lantz <prl@canterey.us> - 2011-12-24 15:29 -0800
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2011-12-24 12:42 +0000
Re: Performance of hand-optimised assembly Jens Gustedt <jens.gustedt@loria.fr> - 2011-12-24 16:58 +0100
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2011-12-24 13:55 +0000
Re: Performance of hand-optimised assembly Seebs <usenet-nospam@seebs.net> - 2011-12-24 19:24 +0000
Re: Performance of hand-optimised assembly Geoff <geoff@invalid.invalid> - 2011-12-24 13:44 -0800
Re: Performance of hand-optimised assembly Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-12-29 02:53 +0200
Re: Performance of hand-optimised assembly Rui Maciel <rui.maciel@gmail.com> - 2011-12-29 02:11 +0000
Re: Performance of hand-optimised assembly jgk@panix.com (Joe keane) - 2011-12-24 01:36 +0000
Re: Performance of hand-optimised assembly "io_x" <a@b.c.invalid> - 2011-12-24 06:44 +0100
Re: Performance of hand-optimised assembly "io_x" <a@b.c.invalid> - 2011-12-24 09:52 +0100
Re: Performance of hand-optimised assembly "io_x" <a@b.c.invalid> - 2011-12-26 08:05 +0100
Re: Performance of hand-optimised assembly 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-26 11:52 -0800
Re: Performance of hand-optimised assembly "io_x" <a@b.c.invalid> - 2011-12-27 07:28 +0100
Re: Performance of hand-optimised assembly Willem <willem@toad.stack.nl> - 2011-12-24 12:48 +0000
Re: Performance of hand-optimised assembly 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-24 04:56 -0800
Re: Performance of hand-optimised assembly Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-24 23:39 +0000
Re: Performance of hand-optimised assembly James Harris <james.harris.1@googlemail.com> - 2011-12-24 06:01 -0800
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2011-12-24 14:55 +0000
Re: Performance of hand-optimised assembly James Harris <james.harris.1@googlemail.com> - 2011-12-28 03:46 -0800
Re: Performance of hand-optimised assembly 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-28 04:52 -0800
Re: Performance of hand-optimised assembly Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-25 00:07 +0000
Re: Performance of hand-optimised assembly James Harris <james.harris.1@googlemail.com> - 2011-12-28 03:21 -0800
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2011-12-28 13:19 +0000
Re: Performance of hand-optimised assembly Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-28 16:01 +0000
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2011-12-28 17:45 +0000
Re: Performance of hand-optimised assembly 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-28 18:56 -0800
Re: Performance of hand-optimised assembly Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-12-29 03:32 +0200
Re: Performance of hand-optimised assembly Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-25 17:03 -0800
Re: Performance of hand-optimised assembly Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-26 22:08 +0000
Re: Performance of hand-optimised assembly Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-31 22:20 -0800
Re: Performance of hand-optimised assembly James Kuyper <jameskuyper@verizon.net> - 2011-12-28 08:24 -0500
Re: Performance of hand-optimised assembly Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-28 14:27 +0000
Re: Performance of hand-optimised assembly Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-25 16:50 -0800
Re: Performance of hand-optimised assembly Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-26 21:59 +0000
Re: Performance of hand-optimised assembly James Harris <james.harris.1@googlemail.com> - 2011-12-28 11:12 -0800
Re: Performance of hand-optimised assembly Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-12-29 03:12 +0200
Re: Performance of hand-optimised assembly jacob navia <jacob@spamsink.net> - 2011-12-29 10:02 +0100
Re: Performance of hand-optimised assembly Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-29 12:06 +0000
Re: Performance of hand-optimised assembly Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-25 17:07 -0800
Re: Performance of hand-optimised assembly Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-02-13 01:18 +0200
Re: Performance of hand-optimised assembly Tim Rentsch <txr@alumni.caltech.edu> - 2012-03-08 10:54 -0800
Re: Performance of hand-optimised assembly jacob navia <jacob@spamsink.net> - 2011-12-29 10:02 +0100
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2011-12-29 12:06 +0000
Re: Performance of hand-optimised assembly Keith Thompson <kst-u@mib.org> - 2011-12-29 11:44 -0800
Re: Performance of hand-optimised assembly Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-25 17:23 -0800
Re: Performance of hand-optimised assembly James Harris <james.harris.1@googlemail.com> - 2011-12-29 08:37 -0800
Re: Performance of hand-optimised assembly Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-01-05 22:19 +0200
Re: Performance of hand-optimised assembly James Dow Allen <gmail@jamesdowallen.nospam> - 2011-12-24 16:21 +0000
Re: Performance of hand-optimised assembly Weland <weland@otaku.freeshell.org> - 2011-12-25 10:54 +0000
Re: Performance of hand-optimised assembly "christian.bau" <christian.bau@cbau.wanadoo.co.uk> - 2011-12-24 14:52 -0800
Re: Performance of hand-optimised assembly jacob navia <jacob@spamsink.net> - 2011-12-25 20:12 +0100
Re: Performance of hand-optimised assembly 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-25 11:36 -0800
Re: Performance of hand-optimised assembly jacob navia <jacob@spamsink.net> - 2011-12-25 21:35 +0100
Re: Performance of hand-optimised assembly Stephen Sprunk <stephen@sprunk.org> - 2011-12-26 14:24 -0600
Re: Performance of hand-optimised assembly jacob navia <jacob@spamsink.net> - 2011-12-26 21:36 +0100
Re: Performance of hand-optimised assembly Stephen Sprunk <stephen@sprunk.org> - 2012-01-04 11:59 -0600
Re: Performance of hand-optimised assembly jacob navia <jacob@spamsink.net> - 2012-01-04 20:22 +0100
Re: Performance of hand-optimised assembly Dann Corbit <dcorbit@connx.com> - 2012-01-04 12:59 -0800
Re: Performance of hand-optimised assembly James Harris <james.harris.1@googlemail.com> - 2012-01-04 15:32 -0800
Re: Performance of hand-optimised assembly Stephen Sprunk <stephen@sprunk.org> - 2012-01-05 23:47 -0600
Re: Performance of hand-optimised assembly Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-04 22:47 +0000
Re: Performance of hand-optimised assembly jacob navia <jacob@spamsink.net> - 2012-01-05 00:47 +0100
Re: Performance of hand-optimised assembly Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-05 00:22 +0000
Re: Performance of hand-optimised assembly 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-04 23:44 -0800
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2012-01-05 12:16 +0000
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2012-01-05 12:49 +0000
Re: Performance of hand-optimised assembly jgk@panix.com (Joe keane) - 2012-01-05 21:26 +0000
Re: Performance of hand-optimised assembly "io_x" <a@b.c.invalid> - 2012-01-07 10:32 +0100
Re: Performance of hand-optimised assembly jacob navia <jacob@spamsink.net> - 2012-01-05 00:58 +0100
Re: Performance of hand-optimised assembly 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-05 13:39 -0800
Re: Performance of hand-optimised assembly 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-07 02:15 -0800
Re: Performance of hand-optimised assembly 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-10 01:07 -0800
Re: Performance of hand-optimised assembly jgk@panix.com (Joe keane) - 2012-01-07 00:49 +0000
Re: Performance of hand-optimised assembly jacob navia <jacob@spamsink.net> - 2012-01-07 08:54 +0100
Re: Performance of hand-optimised assembly jacob navia <jacob@spamsink.net> - 2012-01-07 10:11 +0100
Re: Performance of hand-optimised assembly "io_x" <a@b.c.invalid> - 2012-01-07 10:51 +0100
Re: Performance of hand-optimised assembly jgk@panix.com (Joe keane) - 2012-01-07 20:09 +0000
Re: Performance of hand-optimised assembly Stephen Sprunk <stephen@sprunk.org> - 2012-01-06 23:39 -0600
Re: Performance of hand-optimised assembly jacob navia <jacob@spamsink.net> - 2012-01-07 10:33 +0100
Re: Performance of hand-optimised assembly Stephen Sprunk <stephen@sprunk.org> - 2012-01-07 07:36 -0600
Re: Performance of hand-optimised assembly Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-07 21:03 +0000
Re: Performance of hand-optimised assembly Stephen Sprunk <stephen@sprunk.org> - 2012-01-07 16:42 -0600
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2011-12-25 20:23 +0000
Re: Performance of hand-optimised assembly jacob navia <jacob@spamsink.net> - 2011-12-25 21:50 +0100
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2011-12-25 22:10 +0000
Re: Performance of hand-optimised assembly 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-25 13:11 -0800
Re: Performance of hand-optimised assembly "BartC" <bc@freeuk.com> - 2011-12-25 22:07 +0000
Re: Performance of hand-optimised assembly 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-25 16:39 -0800
Re: Performance of hand-optimised assembly "io_x" <a@b.c.invalid> - 2011-12-26 05:55 +0100
Re: Performance of hand-optimised assembly "io_x" <a@b.c.invalid> - 2012-02-17 17:58 +0100
Re: Performance of hand-optimised assembly "Wolfgang.Draxinger" <Wolfgang.Draxinger@physik.uni-muenchen.de> - 2012-01-10 18:00 +0100
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