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Date: Tue, 13 May 2003 09:07:00 -0000
From: Michael Matz <matz@suse.de>
To: Andrew MacLeod <amacleod@redhat.com>
Cc: gcc mailing list <gcc@gcc.gnu.org>
Subject: Re: [tree-ssa] Out of SSA status and issues
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Hi,

On 12 May 2003, Andrew MacLeod wrote:

> Actually, is propagating this copy a safe thing to do?
>
> Copy propagation simply looks at the def, and if the stmt is a copy,
> copies it... So if there was a store after the definition of i_14 which
> killed the memory location that T.6_12 points to, then the PHI is going
> to get the wrong result...  isn't it?

An indirect reference is not a copy.  I don't know if tree-ssa thinks it
is, but it definitely shouldn't.


Ciao,
Michael.