Is store_expr(e,t,v!=m) safe?

[Jan Hubicka]

> On Mon, Apr 07, 2003 at 11:56:52PM +0200, Jan Hubicka wrote:
> > I think it does not mask it.  The problem is that a[0]=x is converted
> > into load+logicals+store of the whole "a" that fits in DImode that
> > doesn't hurt as long as we don't decide to spit "a" into constant memory
> > area.  Avoid purge_addressof from doing the (pessimizing) transfromation
> > and later changing the mind is the right way to go IMO.
> 
> I disagree.  Indeed, even my patch does not totally fix
> the problem.  There are additional examples in 
> 
>   http://gcc.gnu.org/ml/gcc-patches/2002-12/msg00533.html
> 
> that continue to fail.

How are these related to the addressof pass?  It looks like problem in
the expansion that should either decide to clear the flag or not use
memcpy+initialize nonzero elements sequence.

I see that the unchanging flag goes away when I increase the size of the
structure, so probably someone already takes care for this but forgets
about the case when we go trought addressof.  I can check this tomorrow.

Honza
> 
> 
> r~