[patch] ivopts fixes

[Zdenek Dvorak]

Hello,

> > this patch fixes several problems with ivopts:
> >
> > 1) Ada failures due to misshandling of array_ref_element_size and
> >    array_ref_low_bound are fixed.
> > 2) missing usharing of expressions is added to rewrite_use_outer.
> >    This makes previous fixes of sharing problems in get_computation_at
> >    and iv_value redunant and they are removed.
> > 3) signed and unsigned variants of types are obtained through langhooks
> > 4) dumps now show also types of induction variables
> 
> Thanks. While you were away, there has been some discussion about
> reimplementing peel_address in terms of get_inner_reference (or better, of a
> new function which is the extract body of the loop of get_inner_reference).
> Does this make sense to you?

yes; however Honza told me that the patch he proposed did not work.  I
will have a look at the problem tomorrow.

Zdenek