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In-Reply-To: <430980FC.9070900@lu.unisi.ch>
To: Paolo Bonzini <paolo.bonzini@lu.unisi.ch>
Cc: gcc@gcc.gnu.org
MIME-Version: 1.0
Subject: Re: Question about merging two instructions.
From: Leehod Baruch <LEEHOD@il.ibm.com>
Message-ID: <OFA172C2D5.7846BC73-ONC2257065.00497D7B-C2257065.004A8FF3@il.ibm.com>
Date: Mon, 22 Aug 2005 13:33:00 -0000
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> > 1. Can you please give me an example of something bad that can happen 
to 
> > the LHS.  Maybe I'm missing something here.
> 
> In this case nothing, but if NEW were a subreg, it can change a lot.

Why? 

Do I always need to recognize the result?
If the answer is yes, than I suppose that if something bad happens,
the recognition will fail.

Thanks,
Leehod.