https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111114
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Lehua Ding from comment #2)
> (In reply to Andrew Pinski from comment #1)
> > There is a match pattern which handles the case where the convert (cast)
> > will fold both sides of the vec_cond now (since r14-3337-g70c50c87273d94).
> >
> > vect__5.14_56 = .MASK_LEN_LOAD (vectp_a.12_54, 8B, mask__24.11_52, _67,
> > 0);
> >
> > Is there a way to simplify that with the convert?
> >
> > Or maybe we want to it if one or the other conversion simplifies ....
> >
> > Confirmed.
>
> Thanks for the comments. Can we relax this match by removing the modifier
> "!"?
I don't think so as we want to make sure we don't replace one operation
happening with 2. The check really should be if one side will fold.
We can special case VECTOR_CST here knowing that the convert will fold the CST
always.
So something like:
```
(simplify
(convert (vec_cond:s @0 @1 @2))
(if (VECTOR_TYPE_P (type)
&& types_match (TREE_TYPE (@0), truth_type_for (type)))
(if (TREE_CODE (@1) == VECTOR_CST || TREE_CODE (@2) == VECTOR_CST)
(vec_cond @0 (convert @1) (convert @2)
(vec_cond @0 (convert! @1) (convert! @2)))))
```
We should do a similar trick to both the unary operator and view_convert too.
