Re: Floating point vs fixed arithmetics (signed 64-bit)

From	kishor <kiishor@gmail.com>
Newsgroups	comp.arch.embedded
Subject	Re: Floating point vs fixed arithmetics (signed 64-bit)
Date	2012-03-26 06:33 -0700
Organization	http://groups.google.com
Message-ID	<30610800.3.1332768828757.JavaMail.geo-discussion-forums@pbae2> (permalink)
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On Monday, March 26, 2012 6:08:00 PM UTC+5:30, Fredrik Östman wrote:

> You don't need the division. You need to shift down 31 bits to get back 
> to 32 bits.

I don't understand your point. In signed division we can't shift down bits simply.

> Perhaps the ALU can do to all for you in one step. Check the compiler for 
> a built-in function for 32-bit signed fractional multiplication.
> 
> Read up on fractional arithmetic.

Is there other method which avoids 64-bit division?


Kishore.

Thread

Floating point vs fixed arithmetics (signed 64-bit) kishor <kiishor@gmail.com> - 2012-03-26 02:22 -0700
  Re: Floating point vs fixed arithmetics (signed 64-bit) "Boudewijn Dijkstra" <sp4mtr4p.boudewijn@indes.com> - 2012-03-26 12:08 +0200
  Re: Floating point vs fixed arithmetics (signed 64-bit) Arlet Ottens <usenet+5@c-scape.nl> - 2012-03-26 13:14 +0200
    Re: Floating point vs fixed arithmetics (signed 64-bit) David Brown <david@westcontrol.removethisbit.com> - 2012-03-26 13:24 +0200
      Re: Floating point vs fixed arithmetics (signed 64-bit) kishor <kiishor@gmail.com> - 2012-03-26 05:24 -0700
        Re: Floating point vs fixed arithmetics (signed 64-bit) Fredrik Östman <Fredrik_Oestman@work.invalid> - 2012-03-26 12:38 +0000
          Re: Floating point vs fixed arithmetics (signed 64-bit) kishor <kiishor@gmail.com> - 2012-03-26 06:33 -0700
            Re: Floating point vs fixed arithmetics (signed 64-bit) Arlet Ottens <usenet+5@c-scape.nl> - 2012-03-26 15:49 +0200
            Re: Floating point vs fixed arithmetics (signed 64-bit) David Brown <david@westcontrol.removethisbit.com> - 2012-03-26 15:45 +0200
            Re: Floating point vs fixed arithmetics (signed 64-bit) Fredrik Östman <Fredrik_Oestman@work.invalid> - 2012-03-26 14:34 +0000
        Re: Floating point vs fixed arithmetics (signed 64-bit) Arlet Ottens <usenet+5@c-scape.nl> - 2012-03-26 15:34 +0200
          Re: Floating point vs fixed arithmetics (signed 64-bit) Tim Wescott <tim@seemywebsite.com> - 2012-03-26 12:25 -0500
            Re: Floating point vs fixed arithmetics (signed 64-bit) Arlet Ottens <usenet+5@c-scape.nl> - 2012-03-26 20:19 +0200
              Re: Floating point vs fixed arithmetics (signed 64-bit) Rich Webb <bbew.ar@mapson.nozirev.ten> - 2012-03-26 16:45 -0400
                Re: Floating point vs fixed arithmetics (signed 64-bit) Tim Wescott <tim@seemywebsite.com> - 2012-03-26 17:15 -0500
                Re: Floating point vs fixed arithmetics (signed 64-bit) Rich Webb <bbew.ar@mapson.nozirev.ten> - 2012-03-26 19:09 -0400
                Re: Floating point vs fixed arithmetics (signed 64-bit) kishor <kiishor@gmail.com> - 2012-03-27 04:59 -0700
                Re: Floating point vs fixed arithmetics (signed 64-bit) David Brown <david@westcontrol.removethisbit.com> - 2012-03-27 15:25 +0200
                Re: Floating point vs fixed arithmetics (signed 64-bit) David T. Ashley <dashley@gmail.com> - 2012-03-29 13:17 -0400
  Re: Floating point vs fixed arithmetics (signed 64-bit) "Paul E. Bennett" <Paul_E.Bennett@topmail.co.uk> - 2012-03-27 11:28 +0100
  Re: Floating point vs fixed arithmetics (signed 64-bit) David T. Ashley <dashley@gmail.com> - 2012-03-27 11:28 -0400
    Re: Floating point vs fixed arithmetics (signed 64-bit) upsidedown@downunder.com - 2012-03-27 18:52 +0300
      Re: Floating point vs fixed arithmetics (signed 64-bit) David T. Ashley <dashley@gmail.com> - 2012-03-27 13:02 -0400
        Re: Floating point vs fixed arithmetics (signed 64-bit) Walter Banks <walter@bytecraft.com> - 2012-03-27 13:56 -0500
          Re: Floating point vs fixed arithmetics (signed 64-bit) Tim Wescott <tim@seemywebsite.com> - 2012-03-27 14:17 -0500
            Re: Floating point vs fixed arithmetics (signed 64-bit) Walter Banks <walter@bytecraft.com> - 2012-03-27 15:35 -0500
              Re: Floating point vs fixed arithmetics (signed 64-bit) Tim Wescott <tim@seemywebsite.please> - 2012-03-27 22:36 -0500
          Re: Floating point vs fixed arithmetics (signed 64-bit) David Brown <david@westcontrol.removethisbit.com> - 2012-03-28 09:00 +0200
          Re: Floating point vs fixed arithmetics (signed 64-bit) j.m.granville@gmail.com - 2012-03-30 04:08 -0700
            Re: Floating point vs fixed arithmetics (signed 64-bit) Mark Borgerson <mborgerson@comcast.net> - 2012-04-02 22:52 -0700
              Re: Floating point vs fixed arithmetics (signed 64-bit) John Devereux <john@devereux.me.uk> - 2012-04-03 11:33 +0100
                Re: Floating point vs fixed arithmetics (signed 64-bit) Anders.Montonen@kapsi.spam.stop.fi.invalid - 2012-04-03 12:05 +0000
                Re: Floating point vs fixed arithmetics (signed 64-bit) John Devereux <john@devereux.me.uk> - 2012-04-03 16:34 +0100
                Re: Floating point vs fixed arithmetics (signed 64-bit) Paul <paul@pcserviceselectronics.co.uk> - 2012-04-04 09:35 +0100
            Re: Floating point vs fixed arithmetics (signed 64-bit) Tim Wescott <tim@seemywebsite.com> - 2012-04-03 13:52 -0500
              Re: Floating point vs fixed arithmetics (signed 64-bit) Mark Borgerson <mborgerson@comcast.net> - 2012-04-04 16:50 -0700
                Re: Floating point vs fixed arithmetics (signed 64-bit) John Devereux <john@devereux.me.uk> - 2012-04-05 11:48 +0100
        Re: Floating point vs fixed arithmetics (signed 64-bit) David Brown <david@westcontrol.removethisbit.com> - 2012-03-28 09:17 +0200
          Re: Floating point vs fixed arithmetics (signed 64-bit) Tim Wescott <tim@seemywebsite.com> - 2012-03-28 12:20 -0500
            Re: Floating point vs fixed arithmetics (signed 64-bit) Andrew Reilly <areilly---@bigpond.net.au> - 2012-03-28 22:44 +0000
              Re: Floating point vs fixed arithmetics (signed 64-bit) Tim Wescott <tim@seemywebsite.com> - 2012-03-28 18:35 -0500
                Re: Floating point vs fixed arithmetics (signed 64-bit) David Brown <david@westcontrol.removethisbit.com> - 2012-03-29 10:58 +0200
                Re: Floating point vs fixed arithmetics (signed 64-bit) Mark Borgerson <mborgerson@comcast.net> - 2012-03-29 07:56 -0700
                Re: Floating point vs fixed arithmetics (signed 64-bit) Tim Wescott <tim@seemywebsite.com> - 2012-03-29 16:52 -0500
                Re: Floating point vs fixed arithmetics (signed 64-bit) Mark Borgerson <mborgerson@comcast.net> - 2012-03-29 21:19 -0700
                Re: Floating point vs fixed arithmetics (signed 64-bit) Tim Wescott <tim@seemywebsite.please> - 2012-03-30 00:42 -0500
              Re: Floating point vs fixed arithmetics (signed 64-bit) upsidedown@downunder.com - 2012-03-29 07:19 +0300
                Re: Floating point vs fixed arithmetics (signed 64-bit) Andrew Reilly <areilly---@bigpond.net.au> - 2012-03-29 11:53 +0000
                Re: Floating point vs fixed arithmetics (signed 64-bit) Walter Banks <walter@bytecraft.com> - 2012-03-29 09:40 -0500
                Re: Floating point vs fixed arithmetics (signed 64-bit) upsidedown@downunder.com - 2012-03-29 23:46 +0300
                Re: Floating point vs fixed arithmetics (signed 64-bit) Walter Banks <walter@bytecraft.com> - 2012-03-29 09:28 -0500
                Re: Floating point vs fixed arithmetics (signed 64-bit) David Brown <david@westcontrol.removethisbit.com> - 2012-03-29 16:58 +0200
            Re: Floating point vs fixed arithmetics (signed 64-bit) David Brown <david@westcontrol.removethisbit.com> - 2012-03-29 10:09 +0200
            Re: Floating point vs fixed arithmetics (signed 64-bit) Clifford Heath <cjh@no.spam.please.net> - 2012-04-01 18:08 +1000
          Re: Floating point vs fixed arithmetics (signed 64-bit) dp <dp@tgi-sci.com> - 2012-03-28 02:38 -0700
      Re: Floating point vs fixed arithmetics (signed 64-bit) upsidedown@downunder.com - 2012-03-28 22:59 +0300

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