[Bug target/85323] SSE/AVX/AVX512 shift by 0 not optimized away

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85323

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |jakub at gcc dot gnu.org

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 44082
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44082&action=edit
gcc9-pr85323.patch

Untested WIP patch.  Still need to add testsuite coverage for the case when
both first and second arguments are constant.