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Re: [tree-ssa]: Dominator opts change LHS without changing VDEF's
- From: Diego Novillo <dnovillo at redhat dot com>
- To: Daniel Berlin <dberlin at dberlin dot org>
- Cc: "gcc at gcc dot gnu dot org" <gcc at gcc dot gnu dot org>, Jeff Law <law at redhat dot com>
- Date: Sun, 10 Aug 2003 17:14:58 -0400
- Subject: Re: [tree-ssa]: Dominator opts change LHS without changing VDEF's
- Organization: Red Hat Canada
- References: <363E7410-CB72-11D7-AE61-000A95A34564@dberlin.org>
On Sun, 2003-08-10 at 16:35, Daniel Berlin wrote:
> Diego, this is the bitmap.i problem i sent you.
> This is only visible with points-to on, because it better disambiguates.
> The problem is that dominator opts changes:
>
> # MT.564_34 = VDEF <MT.564_33>;
> # VUSE <bitmap_free_32>;
> elt_29->next = (struct bitmap_element_def *)bitmap_free
>
> into
>
> elt_7->next = (struct bitmap_element_def *)bitmap_free
>
> This causes the vdef's to changes, because the memory tag for elt isn't
> the same as elt.
>
They aren't? Both variables are aliased, are they not? If so, they
should have the same memory tag.
Diego.