Re: code snippet

From	88888 Dihedral <dihedral88888@googlemail.com>
Newsgroups	comp.lang.c
Subject	Re: code snippet
Date	2011-12-22 13:27 -0800
Organization	http://groups.google.com
Message-ID	<9374707.578.1324589230175.JavaMail.geo-discussion-forums@prol32> (permalink)
References	(14 earlier) <0.ceef25457ffad09d0acb.20111222193427GMT.87zkekl7ss.fsf@bsb.me.uk> <2372733.489.1324583849963.JavaMail.geo-discussion-forums@prix23> <slrnjf744e.223p.usenet-nospam@guild.seebs.net> <8093011.520.1324587134285.JavaMail.geo-discussion-forums@prlk31> <slrnjf7738.23eo.usenet-nospam@guild.seebs.net>

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On Friday, December 23, 2011 4:37:03 AM UTC+8, Seebs wrote:
> On 2011-12-22, 88888 Dihedral <dihedr...@googlemail.com> wrote:
> > I use about  20 to 26  instructions only in those various kinds of 
> > cpus I played with. 
> 
> That gives you another significant disadvantage compared to the compiler.
> 
> > If the compiler is smarter than a professional programmer, 
> > then a lot novice programmers should be fired for not producing 
> > smart and fast programs.   
> 
> "Smarter" is a pretty broad term.
> 
> >Of course I check those instructions that preserve the flags also
> >those control flow instructions with the most likely first in my assembly.
> 
> The compiler can consider more possible sequences of instructions per second
> than you can per month.  The compiler also has the option of using
> instructions that don't preserve flags, and thus gaining advantages from
> using the flags as intended, and can avoid flow control when it's the
> wrong choice.
> 
> Dunno if you saw this, but a while back, someone had some PRNG code here,
> which included a snippet roughly to the effect of:
> 
> 	if (z)
> 		x += y;
> 
> Replacing this with:
> 	x += (y * z);
> 
> dramatically improved the efficiency of the entire PRNG, because that branch
> had been slowing it down more than any five or ten other instructions.
> 
> You are doubtless better at some *kinds* of thinking than a compiler, but you
> generally won't beat a modern compiler by enough to notice, and indeed, my
> experience has been that people who think they can beat compilers normally
> lose to compilers.  The only people I've seen beat modern compilers are people
> who understand why they normally can't.  :)
> 
> -s
> -- 
> Copyright 2011, all wrongs reversed.  Peter Seebach / usenet...@seebs.net
> http://www.seebs.net/log/ <-- lawsuits, religion, and funny pictures
> http://en.wikipedia.org/wiki/Fair_Game_(Scientology) <-- get educated!
> I am not speaking for my employer, although they do rent some of my opinions.

OK, you are selling compilers. I am working on compilers in GCC and  MINI C 
PORTABLE C and device C!

If you are selling arm compilers, then I agree with you.

Thread

code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-18 20:51 -0500
  Re: code snippet Geoff <geoff@invalid.invalid> - 2011-12-18 18:29 -0800
    Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-18 21:51 -0500
      Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-18 22:24 -0500
        Re: code snippet Geoff <geoff@invalid.invalid> - 2011-12-18 19:53 -0800
          Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-18 23:32 -0500
            Re: code snippet Geoff <geoff@invalid.invalid> - 2011-12-18 20:57 -0800
              Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-19 00:01 -0500
                Re: code snippet Geoff <geoff@invalid.invalid> - 2011-12-18 21:13 -0800
                Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-19 16:42 -0500
      Re: code snippet Keith Thompson <kst-u@mib.org> - 2011-12-18 20:14 -0800
        Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-18 23:27 -0500
      Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-19 12:33 +0000
        Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-19 16:33 -0500
          Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-20 00:20 +0000
            Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-19 19:46 -0500
              Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-20 01:14 +0000
                Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-20 15:51 -0500
                Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-21 14:11 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-21 07:03 -0800
                Re: code snippet Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-21 21:41 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-21 16:35 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 01:03 +0000
                Re: code snippet Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-22 03:19 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 07:11 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 16:59 +0000
                Re: code snippet "io_x" <a@b.c.invalid> - 2011-12-22 18:38 +0100
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 10:40 -0800
                Re: code snippet Markus Wichmann <nullplan@gmx.net> - 2011-12-22 19:12 +0100
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-12-28 03:50 -0800
                Re: code snippet "io_x" <a@b.c.invalid> - 2011-12-28 17:06 +0100
                Re: code snippet "io_x" <a@b.c.invalid> - 2012-01-01 20:04 +0100
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-01 12:38 -0800
                Re: code snippet "io_x" <a@b.c.invalid> - 2012-01-02 10:14 +0100
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-03 04:56 -0800
                Re: code snippet "io_x" <a@b.c.invalid> - 2012-01-03 18:26 +0100
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-04 00:09 -0800
                Re: code snippet Ian Collins <ian-news@hotmail.com> - 2012-01-04 21:53 +1300
                Re: code snippet "io_x" <a@b.c.invalid> - 2012-01-04 16:14 +0100
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-01 12:28 -0800
                Re: code snippet "io_x" <a@b.c.invalid> - 2012-01-02 10:18 +0100
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-03 04:56 -0800
                Re: code snippet "BartC" <bc@freeuk.com> - 2011-12-22 18:05 +0000
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 18:14 +0000
                Re: code snippet superpollo <superpollo@tznvy.pbz> - 2011-12-22 20:00 +0100
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 19:08 +0000
                Re: code snippet superpollo <superpollo@tznvy.pbz> - 2011-12-22 22:43 +0100
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 21:57 +0000
                Re: code snippet BruceS <bruces42@hotmail.com> - 2011-12-23 16:26 -0800
                Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-22 19:21 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 11:33 -0800
                Re: code snippet "io_x" <a@b.c.invalid> - 2011-12-23 09:10 +0100
                Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-23 14:43 +0000
                Re: code snippet Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-23 17:14 +0000
                Re: code snippet Keith Thompson <kst-u@mib.org> - 2011-12-23 12:10 -0800
                Re: code snippet Walter Banks <walter@bytecraft.com> - 2012-01-03 14:24 -0500
                Re: code snippet Kaz Kylheku <kaz@kylheku.com> - 2012-01-03 19:58 +0000
                Re: code snippet Walter Banks <walter@bytecraft.com> - 2012-01-03 16:15 -0500
                Re: code snippet blp@cs.stanford.edu (Ben Pfaff) - 2012-01-03 13:26 -0800
                Re: code snippet Kaz Kylheku <kaz@kylheku.com> - 2012-01-03 22:04 +0000
                Re: code snippet Ian Collins <ian-news@hotmail.com> - 2012-01-04 15:44 +1300
                Re: code snippet "BartC" <bc@freeuk.com> - 2012-01-04 23:34 +0000
                Re: code snippet James Harris <james.harris.1@googlemail.com> - 2012-01-04 15:57 -0800
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-05 23:34 -0800
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-06 00:40 -0800
                Re: code snippet Kleuske <kleuske@nowhere.net> - 2012-01-06 10:33 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-06 04:30 -0800
                Re: code snippet Ian Collins <ian-news@hotmail.com> - 2012-01-04 15:37 +1300
                Re: code snippet Kaz Kylheku <kaz@kylheku.com> - 2012-01-04 03:37 +0000
                Re: code snippet Ian Collins <ian-news@hotmail.com> - 2012-01-04 20:23 +1300
                Re: code snippet jacob navia <jacob@spamsink.net> - 2011-12-22 18:26 +0100
                Re: code snippet Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-22 19:34 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 11:57 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 20:18 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 12:52 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 20:37 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 13:27 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 21:57 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 14:09 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 21:57 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-23 04:01 -0800
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-22 14:24 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-22 21:57 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2012-01-01 23:06 -0800
                Re: code snippet Hans Vlems <hvlems@freenet.de> - 2011-12-22 23:35 -0800
                Re: code snippet "BartC" <bc@freeuk.com> - 2011-12-23 12:26 +0000
                Re: code snippet jacob navia <jacob@spamsink.net> - 2011-12-23 18:32 +0100
                Re: code snippet Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-12-28 04:04 -0800
                Re: code snippet "io_x" <a@b.c.invalid> - 2011-12-23 09:10 +0100
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-25 11:13 -0800
                Re: code snippet Seebs <usenet-nospam@seebs.net> - 2011-12-25 19:31 +0000
                Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-26 21:53 +0000
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-26 16:10 -0800
                Re: code snippet Keith Thompson <kst-u@mib.org> - 2011-12-26 18:11 -0800
                Re: code snippet 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-26 23:56 -0800
                Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-20 15:57 -0500
                Re: code snippet Rui Maciel <rui.maciel@gmail.com> - 2011-12-21 12:39 +0000
                Re: code snippet Bill Reid <hormelfree@gmail.com> - 2011-12-22 15:29 -0800
          Re: code snippet Geoff <geoff@invalid.invalid> - 2011-12-19 19:19 -0800
            Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-20 13:51 -0500
              Re: code snippet Geoff <geoff@invalid.invalid> - 2011-12-20 11:08 -0800
  Re: code snippet Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-12-19 11:37 +0000
    Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-19 16:38 -0500
      Re: code snippet "Morris Keesan" <mkeesan@post.harvard.edu> - 2011-12-19 17:02 -0500
    Re: code snippet "Bill Cunningham" <nospam@nspam.invalid> - 2011-12-19 17:21 -0500
      Re: code snippet John Gordon <gordon@panix.com> - 2011-12-19 22:35 +0000

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