Re: How to eliminate redundant constant move instructions

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From	mac <acolvin@efunct.com>
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Subject	Re: How to eliminate redundant constant move instructions
Date	Thu, 3 Nov 2011 02:20:40 +0000 (UTC)
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>> I found following intermediate codes are generated in gcc
>>
>> rx <- 0
>> ...
>> use rx
>> ...
>> ry <- 0
>> use ry
>> ...

This may be "rematerialization", which probably has other names.

Sometimes it's better to re-compute a common value than to tie up a
register. This may well be true for a constant 0 if there are few registers
(x86-32).

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How to eliminate redundant constant move instructions "Amker.Cheng" <amker.cheng@gmail.com> - 2011-10-31 17:53 +0800
  Re: How to eliminate redundant constant move instructions Kaz Kylheku <kaz@kylheku.com> - 2011-10-31 17:08 +0000
    Re: How to eliminate redundant constant move instructions amker <can.finner@gmail.com> - 2011-11-01 19:01 -0700
    Re: How to eliminate redundant constant move instructions mac <acolvin@efunct.com> - 2011-11-03 02:20 +0000
  Re: How to eliminate redundant constant move instructions George Neuner <gneuner2@comcast.net> - 2011-11-01 14:32 -0400
    Re: How to eliminate redundant constant move instructions glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-11-01 22:35 +0000
      Re: How to eliminate redundant constant move instructions amker <can.finner@gmail.com> - 2011-11-01 19:35 -0700
      Re: How to eliminate redundant constant move instructions amker <amker.cheng@gmail.com> - 2011-11-01 21:04 -0700
      Re: How to eliminate redundant constant move instructions George Neuner <gneuner2@comcast.net> - 2011-11-02 12:38 -0400
        Re: How to eliminate redundant constant move instructions Kaz Kylheku <kaz@kylheku.com> - 2011-11-03 03:20 +0000
          Re: How to eliminate redundant constant move instructions George Neuner <gneuner2@comcast.net> - 2011-11-04 13:27 -0400
            Re: How to eliminate redundant constant move instructions glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-11-04 21:19 +0000
        Re: How to eliminate redundant constant move instructions glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-11-03 03:32 +0000
    Re: How to eliminate redundant constant move instructions amker <can.finner@gmail.com> - 2011-11-01 19:21 -0700
      Re: How to eliminate redundant constant move instructions George Neuner <gneuner2@comcast.net> - 2011-11-04 17:26 -0400
        Re: How to eliminate redundant constant move instructions amker <amker.cheng@gmail.com> - 2011-11-07 17:33 -0800
          Re: How to eliminate redundant constant move instructions Wei-Jen Chen <chenwj@cs.NCTU.edu.tw> - 2011-11-10 08:04 +0000
          Re: How to eliminate redundant constant move instructions George Neuner <gneuner2@comcast.net> - 2011-11-10 18:18 -0500
    Re: How to eliminate redundant constant move instructions amker <amker.cheng@gmail.com> - 2011-11-01 20:58 -0700

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