Fix IA-64 bootstrap failure

[Jakub Jelinek]

On Thu, Jan 29, 2004 at 01:45:57AM +0100, Jan Hubicka wrote:
> > Jan Hubicka wrote:
> > >	* alias.c (find_base_term, get_addr):  Do not dereference NULL
> > >	pointer when all VALUE's locations has been invalidated.
> > 
> > This patch looks like the right idea.  If CSELIB_VAL_PTR is NULL, then 
> > we have no alias info at all.
> > 
> > I believe you missed one place that needs to be fixed.  Just searching 
> > for CSELIB_VAL_PTR, I see code in rtx_equal_for_memref_p
> >     case VALUE:
> >       return CSELIB_VAL_PTR (x) == CSELIB_VAL_PTR (y);
> 
> I am also re-running the bootstrap with this changed to x==y.
> In the past I did a check that VALUEs are never copied, so this shall be
> enough to ensure that the test shall not be too conservative modulo to
> NULL values.

If you are changing return CSELIB_VAL_PTR (x) == CSELIB_VAL_PTR (y);
to return x == y;, you may as well change it to return 0; immediately,
because there is
  if (x == y)
    return 1;
earlier in rtx_equal_for_memref_p.

	Jakub