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From: mac <acolvin@efunct.com>
Newsgroups: comp.compilers
Subject: Re: How to eliminate redundant constant move instructions
Date: Thu, 3 Nov 2011 02:20:40 +0000 (UTC)
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Xref: x330-a1.tempe.blueboxinc.net comp.compilers:319

>> 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).