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Re: Optimisation questions

From Dann Corbit <dcorbit@connx.com>
Newsgroups comp.lang.c
Subject Re: Optimisation questions
Date 2012-02-07 14:25 -0800
Organization Aioe.org NNTP Server
Message-ID <MPG.299b44a3c8cf81aa989694@aioe.org> (permalink)
References (2 earlier) <jgkgra$886$1@dont-email.me> <jgkou6$g96$1@dont-email.me> <20120205034114.797@kylheku.com> <MPG.2999b0533378d8cf989693@aioe.org> <c0l709-4iv.ln1@voyager.wichi.de.vu>

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In article <c0l709-4iv.ln1@voyager.wichi.de.vu>, nullplan@gmx.net 
says...
> 
> > I guess that the bottom line is that if you need the last little 
> > smackerel of performance then you have better try all the alternatives 
> > and benchmark them.
> 
> You could simply tell the compiler that that number won't be negative,
> in which case adding code for rounding towards zero won't be necessary.
> But no, you have to do it the hard way.

The original poster had signed integers.
I have no idea if it matter if they are signed or not.
I do understand the opimizations available for unsigned integers, since 
I write bitmap based chess programs for a hobby.

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Thread

Optimisation questions Raj Pashwar <raj121190@hotmail.NOSPAM.com> - 2012-02-04 22:30 +0000
  Re: Optimisation questions Ian Collins <ian-news@hotmail.com> - 2012-02-05 11:44 +1300
    Re: Optimisation questions Keith Thompson <kst-u@mib.org> - 2012-02-04 14:52 -0800
      Re: Optimisation questions Ian Collins <ian-news@hotmail.com> - 2012-02-05 11:55 +1300
      Re: Optimisation questions Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-02-21 18:41 +0200
  Re: Optimisation questions "BartC" <bc@freeuk.com> - 2012-02-04 22:44 +0000
    Re: Optimisation questions "BartC" <bc@freeuk.com> - 2012-02-04 23:41 +0000
  Re: Optimisation questions Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-02-04 17:51 -0500
  Re: Optimisation questions Keith Thompson <kst-u@mib.org> - 2012-02-04 14:52 -0800
  Re: Optimisation questions James Kuyper <jameskuyper@verizon.net> - 2012-02-04 18:44 -0500
    Re: Optimisation questions Stephen Sprunk <stephen@sprunk.org> - 2012-02-04 18:00 -0600
      Re: Optimisation questions James Kuyper <jameskuyper@verizon.net> - 2012-02-04 21:18 -0500
        Re: Optimisation questions Kaz Kylheku <kaz@kylheku.com> - 2012-02-05 03:04 +0000
          Re: Optimisation questions Dann Corbit <dcorbit@connx.com> - 2012-02-06 09:40 -0800
            Re: Optimisation questions Willem <willem@toad.stack.nl> - 2012-02-06 18:51 +0000
            Re: Optimisation questions Markus Wichmann <nullplan@gmx.net> - 2012-02-07 14:19 +0100
              Re: Optimisation questions Dann Corbit <dcorbit@connx.com> - 2012-02-07 14:25 -0800
          Re: Optimisation questions Stephen Sprunk <stephen@sprunk.org> - 2012-02-06 17:29 -0600
            Re: Optimisation questions Kaz Kylheku <kaz@kylheku.com> - 2012-02-06 23:52 +0000
            Re: Optimisation questions pete <pfiland@mindspring.com> - 2012-02-06 19:10 -0500
    Re: Optimisation questions Raj Pashwar <raj121190@hotmail.NOSPAM.com> - 2012-02-05 10:51 +0000
      Re: Optimisation questions Ian Collins <ian-news@hotmail.com> - 2012-02-06 00:08 +1300
        Re: Optimisation questions Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-02-05 08:13 -0500
      Re: Optimisation questions "BartC" <bc@freeuk.com> - 2012-02-05 11:33 +0000
      Re: Optimisation questions Zoltan Kocsi <zoltan@bendor.com.au> - 2012-02-05 23:24 +1100
        Re: Optimisation questions Raj Pashwar <raj121190@hotmail.NOSPAM.com> - 2012-02-05 22:28 +0000
          Re: Optimisation questions Kaz Kylheku <kaz@kylheku.com> - 2012-02-05 22:37 +0000
          Re: Optimisation questions Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-02-05 17:48 -0500
          Re: Optimisation questions Keith Thompson <kst-u@mib.org> - 2012-02-05 15:57 -0800
      Re: Optimisation questions "BartC" <bc@freeuk.com> - 2012-02-05 12:53 +0000
  Re: Optimisation questions Geoff <geoff@invalid.invalid> - 2012-02-04 16:07 -0800
  Re: Optimisation questions "christian.bau" <christian.bau@cbau.wanadoo.co.uk> - 2012-02-04 15:37 -0800
    Re: Optimisation questions Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-02-05 04:26 -0800
      Re: Optimisation questions lawrence.jones@siemens.com - 2012-02-07 10:56 -0500
  Re: Optimisation questions Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-02-05 04:29 -0800
  Re: Optimisation questions Michael Angelo Ravera <maravera@prodigy.net> - 2012-02-05 23:24 -0800

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