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Re: Java left shift and right shift operators.

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Subject	Re: Java left shift and right shift operators.
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On 4/26/2011 9:32 AM, Sanny wrote:
...
> I have computed and found "if statments" take 20-50 times longer than
> basic arithmetic operations. So I wanted to replace if condition by
> some arithmetics/ Maths.
...

You are seriously underestimating the range of variation of if-statement
time. It can be just as fast as an arithmetic statement. It must be
measured in context - you could be wasting your time if the actual mix
of left and right shifts has a pattern the branch predictor can pick up.

Patricia

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Java left shift and right shift operators. Sanny <softtanks22@hotmail.com> - 2011-04-26 00:38 -0700
  Re: Java left shift and right shift operators. Lothar Kimmeringer <news200709@kimmeringer.de> - 2011-04-26 09:55 +0200
    Re: Java left shift and right shift operators. Patricia Shanahan <pats@acm.org> - 2011-04-26 03:16 -0700
    Re: Java left shift and right shift operators. Lew <noone@lewscanon.com> - 2011-04-26 09:49 -0400
      Re: Java left shift and right shift operators. Travers Naran <tnaran@gmail.com> - 2011-04-26 07:09 -0700
        Re: Java left shift and right shift operators. Lew <noone@lewscanon.com> - 2011-04-26 11:21 -0400
        Re: Java left shift and right shift operators. Martin Gregorie <martin@address-in-sig.invalid> - 2011-04-26 15:37 +0000
      Re: Java left shift and right shift operators. Sanny <softtanks22@hotmail.com> - 2011-04-26 09:32 -0700
        Re: Java left shift and right shift operators. Patricia Shanahan <pats@acm.org> - 2011-04-26 11:09 -0700
          Re: Java left shift and right shift operators. Patricia Shanahan <pats@acm.org> - 2011-04-26 13:09 -0700
        Re: Java left shift and right shift operators. Travers Naran <tnaran@gmail.com> - 2011-04-26 22:40 -0700
          Re: Java left shift and right shift operators. Patricia Shanahan <pats@acm.org> - 2011-04-27 05:34 -0700
            Re: Java left shift and right shift operators. Owen Jacobson <angrybaldguy@gmail.com> - 2011-04-28 00:37 -0400
              Re: Java left shift and right shift operators. Patricia Shanahan <pats@acm.org> - 2011-04-28 16:02 -0700
              Re: Java left shift and right shift operators. Michael Wojcik <mwojcik@newsguy.com> - 2011-04-28 19:22 -0400
          Re: Java left shift and right shift operators. bugbear <bugbear@trim_papermule.co.uk_trim> - 2011-04-27 14:28 +0100
          Re: Java left shift and right shift operators. Thomas Richter <thor@math.tu-berlin.de> - 2011-04-30 00:02 +0200
      Re: Java left shift and right shift operators. Roedy Green <see_website@mindprod.com.invalid> - 2011-04-27 19:25 -0700
        Re: Java left shift and right shift operators. Lew <noone@lewscanon.com> - 2011-04-27 23:08 -0400
  Re: Java left shift and right shift operators. Sanny <softtanks22@hotmail.com> - 2011-04-26 02:04 -0700
    Re: Java left shift and right shift operators. Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-04-26 07:34 -0400
      Re: Java left shift and right shift operators. Lew <noone@lewscanon.com> - 2011-04-26 09:47 -0400
        Re: Java left shift and right shift operators. Patricia Shanahan <pats@acm.org> - 2011-04-27 09:23 -0700
          Re: Java left shift and right shift operators. Lew <noone@lewscanon.com> - 2011-04-27 14:49 -0400
            Re: Java left shift and right shift operators. Paul Cager <paul.cager@googlemail.com> - 2011-04-27 17:28 -0700
              Re: Java left shift and right shift operators. Lew <noone@lewscanon.com> - 2011-04-27 22:06 -0400
      Re: Java left shift and right shift operators. Sanny <softtanks22@hotmail.com> - 2011-04-26 09:39 -0700
        Re: Java left shift and right shift operators. Patricia Shanahan <pats@acm.org> - 2011-04-26 11:17 -0700
        Re: Java left shift and right shift operators. Lew <noone@lewscanon.com> - 2011-04-26 14:55 -0400
          Re: Java left shift and right shift operators. Lew <noone@lewscanon.com> - 2011-04-26 14:57 -0400
          Re: Java left shift and right shift operators. Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2011-04-26 21:38 +0200
          Re: Java left shift and right shift operators. Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2011-04-26 23:32 +0000
            Re: Java left shift and right shift operators. Lew <noone@lewscanon.com> - 2011-04-27 00:08 -0400
              Re: Java left shift and right shift operators. Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2011-04-27 06:57 +0000
                Re: Java left shift and right shift operators. Arved Sandstrom <asandstrom3minus1@eastlink.ca> - 2011-04-27 07:00 -0300
                Re: Java left shift and right shift operators. Lew <noone@lewscanon.com> - 2011-04-27 08:42 -0400
                Re: Java left shift and right shift operators. Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2011-04-27 14:03 +0000
                Re: Java left shift and right shift operators. Lew <noone@lewscanon.com> - 2011-04-27 14:54 -0400
        Re: Java left shift and right shift operators. Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-04-26 21:14 -0400
    Re: Java left shift and right shift operators. Travers Naran <tnaran@gmail.com> - 2011-04-26 07:30 -0700
      Re: Java left shift and right shift operators. Lew <noone@lewscanon.com> - 2011-04-26 11:24 -0400
        Re: Java left shift and right shift operators. Lew <noone@lewscanon.com> - 2011-04-26 11:35 -0400
          Re: Java left shift and right shift operators. Sanny <softtanks22@hotmail.com> - 2011-04-26 09:46 -0700
            Re: Java left shift and right shift operators. Lew <noone@lewscanon.com> - 2011-04-26 15:02 -0400
      Re: Java left shift and right shift operators. Lothar Kimmeringer <news200709@kimmeringer.de> - 2011-04-28 09:14 +0200
  Re: Java left shift and right shift operators. Joshua Cranmer <Pidgeot18@verizon.invalid> - 2011-04-26 08:41 -0400
  Re: Java left shift and right shift operators. Robert Klemme <shortcutter@googlemail.com> - 2011-04-26 22:06 +0200

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