[Bug rtl-optimization/97249] Missing vec_select and subreg optimization

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97249

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2020-09-30
                 CC|                            |segher at gcc dot gnu.org
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
Guess you want to figure what built the (vec_select:V8QI (V16QI)) and if
it was appropriately simplified (and simplify_rtx would handle this case).
In any case the vec_select is the same as (subreg:V8QI (V16QI)).