Hi!
On Mon, May 11, 2020 at 09:56:14PM -0500, Bill Schmidt wrote:
> On 5/11/20 9:48 AM, David Edelsohn wrote:
> >On Sun, May 10, 2020 at 9:14 AM Bill Schmidt <wschm...@linux.ibm.com>
> >wrote:
> >> * config/rs6000/altivec.md (UNSPEC_EXTRACTL): New constant.
> >> (UNSPEC_EXTRACTR): Likewise.
> >> (VEXTRACT_LR): New int iterator.
> >Well now the previous VSTRIR/VSTRIL patch is inconsistent. If we're
> >going to use an iterator for "LR", that's fine, but it needs to be
> >used consistently for similar situations. The approach for the two,
> >similar instructions and issues need to match.
>
> I see your point. I don't really like the way this was done very much,
> since the attributes are tied to the unspecs for extract-{low,high}.
> Simple attribute names like LR, lr, rl shouldn't be scoped so narrowly.
Yeah... The point was to make the resulting code readable. xx<lr> is
readable, but xx<some_long_name_lr> is not.
> I don't like any of the alternatives very well, either. I could either
> (1) change the names of the int iterators in this patch to incorporate
> part of the word "extract", and create similar iterators for the
> vstril/vstrir patterns; or (2) remove the iterators from this patch and
> just create two expansions and two insns instead of one of each. I have
> a slight preference for (2) since the longer iterator names will make
> things ugly.
>
> Do you or Segher have a preference?
Two patterns is the best idea I think.
And all of this will be less code if you can move the decision making
part to the builtin code?
Segher
