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Re: Shifting bits

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On Thursday, December 1, 2011 5:41:10 AM UTC+8, Seebs wrote:
> On 2011-11-30, 88888 Dihedral <dihedr...@googlemail.com> wrote:
> > On Thursday, December 1, 2011 2:43:57 AM UTC+8, Seebs wrote:
> >> On 2011-11-30, 88888 Dihedral <dihe...@googlemail.com> wrote:
> >> > I think I am not the only one interested in using arm family riscs that do 
> >> > not have multipliers and dividers.
> 
> >> Boy, sure would be nice if compiler writers had solved this a decade or
> >> two back.
> 
> >> It's long since been done.
>  
> > Did you profile those so slow ?
> 
> No, I didn't, because in all the thousands of ARM builds I've run, it's
> never, once, been an issue.  To put it in perspective, while I am vaguely
> aware that some ARM hardware lacks hardware divide, I couldn't even tell
> you which of the couple dozen ARM chips we actively support are affected,
> because it has never, ever, been a measurable issue.
> 
> Compilers are already well aware of the need for efficient division, and if
> I had to bet on a competition between the gcc ARM port maintainers and you
> for producing an efficient divider, I would bet on the gcc folks.
> 
> -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 or your boss  paid the tax to the compiler writers. 

How about a new cpu without a divider or a multiplier, e.g. ARM7?

  

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Shifting bits arnuld <sunrise@invalid.address> - 2011-11-29 05:02 +0000
  Re: Shifting bits Ian Collins <ian-news@hotmail.com> - 2011-11-29 18:20 +1300
    Re: Shifting bits Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-11-29 17:39 +0000
      Re: Shifting bits arnuld <sunrise@invalid.address> - 2011-11-30 05:53 +0000
        Re: Shifting bits James Kuyper <jameskuyper@verizon.net> - 2011-11-30 06:57 -0500
        Re: Shifting bits Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-11-30 18:31 +0200
          Re: Shifting bits Ralf Damaschke <rwspam@gmx.de> - 2011-12-01 14:41 +0000
            Re: Shifting bits lawrence.jones@siemens.com - 2011-12-01 13:58 -0500
        Re: Shifting bits Stanley Rice <heconghui@gmail.com> - 2011-11-30 18:11 -0800
          Re: Shifting bits Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-12-01 02:21 -0800
  Re: Shifting bits Malcolm McLean <malcolm.mclean5@btinternet.com> - 2011-11-29 03:03 -0800
  Re: Shifting bits "BartC" <bc@freeuk.com> - 2011-11-29 12:04 +0000
    Re: Shifting bits 88888 Dihedral <dihedral88888@googlemail.com> - 2011-11-29 05:44 -0800
    Re: Shifting bits arnuld <sunrise@invalid.address> - 2011-11-30 05:58 +0000
  Re: Shifting bits gwowen <gwowen@gmail.com> - 2011-11-29 08:21 -0800
  Re: Shifting bits DDD <1983ddd@gmail.com> - 2011-11-29 20:42 -0800
    Re: Shifting bits James Kuyper <jameskuyper@verizon.net> - 2011-11-30 00:11 -0500
      Re: Shifting bits Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-11-30 18:23 +0200
        Re: Shifting bits Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-12-01 02:23 -0800
  Re: Shifting bits 88888 Dihedral <dihedral88888@googlemail.com> - 2011-11-30 05:35 -0800
    Re: Shifting bits Seebs <usenet-nospam@seebs.net> - 2011-11-30 18:43 +0000
      Re: Shifting bits 88888 Dihedral <dihedral88888@googlemail.com> - 2011-11-30 13:33 -0800
        Re: Shifting bits Seebs <usenet-nospam@seebs.net> - 2011-11-30 21:41 +0000
          Re: Shifting bits 88888 Dihedral <dihedral88888@googlemail.com> - 2011-11-30 14:40 -0800
            Re: Shifting bits Seebs <usenet-nospam@seebs.net> - 2011-11-30 22:36 +0000
              Re: Shifting bits Lauri Alanko <la@iki.fi> - 2011-12-01 02:02 +0000
                Re: Shifting bits Lowell Gilbert <lgusenet@be-well.ilk.org> - 2011-12-01 09:30 -0500
              Re: Shifting bits Kaz Kylheku <kaz@kylheku.com> - 2011-12-01 02:50 +0000
                Re: Shifting bits Lowell Gilbert <lgusenet@be-well.ilk.org> - 2011-12-01 09:00 -0500
      Re: Shifting bits Robert Wessel <robertwessel2@yahoo.com> - 2011-11-30 17:09 -0600
    Re: Shifting bits Stanley Rice <heconghui@gmail.com> - 2011-11-30 18:13 -0800
      Re: Shifting bits Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-11-30 19:44 -0700
      Re: Shifting bits Keith Thompson <kst-u@mib.org> - 2011-11-30 19:20 -0800
      Re: Shifting bits Seebs <usenet-nospam@seebs.net> - 2011-12-01 20:08 +0000
      Re: Shifting bits Kaz Kylheku <kaz@kylheku.com> - 2011-12-01 21:34 +0000
  Re: Shifting bits gordonb.slo24@burditt.org (Gordon Burditt) - 2011-12-01 01:24 -0600

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