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Date: Thu, 12 Dec 2002 12:25:00 -0000
From: Richard Henderson <rth@redhat.com>
To: Daniel Berlin <dberlin@dberlin.org>
Cc: Dale Johannesen <dalej@apple.com>,
   "Sanjiv Kumar Gupta, Noida" <sanjivg@noida.hcltech.com>, gcc@gcc.gnu.org
Subject: Re: possible gcse failure: not able to eliminate redundant loads
Message-ID: <20021212200530.GA23940@redhat.com>
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	Daniel Berlin <dberlin@dberlin.org>,
	Dale Johannesen <dalej@apple.com>,
	"Sanjiv Kumar Gupta, Noida" <sanjivg@noida.hcltech.com>,
	gcc@gcc.gnu.org
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On Wed, Dec 11, 2002 at 08:50:01PM -0500, Daniel Berlin wrote:
> >>>       for (i ; i < 3; i = i + 8)
> >>>       {
> >>>               a[4] = a[1];
> >>>       }
[...]
> Store motion can't handle this right now.

This shouldn't have anything to do with store motion.  Not for this
simple case.  If these memories are known to not alias, then they
should be hoisted out of the loop by load_mems.

To me it's clear that this is an alias.c defect.


r~