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Re: [autovect] [patch] and aliasing question
- From: Ira Rosen <IRAR at il dot ibm dot com>
- To: Diego Novillo <dnovillo at redhat dot com>
- Cc: Daniel Berlin <dberlin at dberlin dot org>, gcc-patches at gcc dot gnu dot org
- Date: Thu, 26 May 2005 15:18:01 +0300
- Subject: Re: [autovect] [patch] and aliasing question
Diego Novillo <dnovillo@redhat.com> wrote on 26/05/2005 14:02:10:
> On Thu, May 26, 2005 at 12:21:24PM +0300, Ira Rosen wrote:
>
> > vect-77v.c (attached)
> > ib_16 doesn't have a TMT
> >
> Because it is never dereferenced. We only create memory tags for
> dereferenced pointers. The aliaser decides that it is
> pointless to compute aliasing information for a non-dereferenced
> pointer, because there are no loads/stores to the pointed-to
> memory.
>
> Is this a problem for your analysis? Do you need points-to
> information for non-dereferenced pointers as well?
We get to ib_16 with our data-ref analysis for *D.1607_25:
D.1607_25 = ib_16 + D.1606_24;
D.1608_26 = *D.1607_25;
I guess in such cases, we can get the tag from the original reference.
Thanks,
Ira