Re: Avoid generating useless range info

[Jakub Jelinek <jakub@redhat.com>]

On Fri, Jun 23, 2017 at 12:24:25PM +0200, Richard Biener wrote:
> > void
> > set_nonzero_bits (tree name, const wide_int_ref &mask)
> > {
> >   gcc_assert (!POINTER_TYPE_P (TREE_TYPE (name)));
> >   if (SSA_NAME_RANGE_INFO (name) == NULL)
> >     set_range_info (name, VR_RANGE,
> >    TYPE_MIN_VALUE (TREE_TYPE (name)),
> >    TYPE_MAX_VALUE (TREE_TYPE (name)));
> >   range_info_def *ri = SSA_NAME_RANGE_INFO (name);
> >   ri->set_nonzero_bits (mask);
> > }
> >
> > Let me know how you'd like me to proceed.
> 
> Just factor out a set_range_info_raw and call that then from here.

And don't call it if the mask is all ones.  Perhaps set_range_info
and set_nonzero_bits even should ggc_free and clear earlier range_info_def
if the range is all values and nonzero bit mask is all ones.
Or do we share range_info_def between multiple SSA_NAMEs?  If yes, of course
we shouldn't use ggc_free.

	Jakub