[Bug tree-optimization/101668] BB vectorizer doesn't handle lowpart of existing vector

[rguenth at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101668

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

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

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
Some pending enhancements would allow us to use VEC_PERM_EXPR with different
input modes from output mode and thus make implementation of this easier.
vectorizable_slp_permutation doesn't yet support that though.

For the special case of a contiguous permutation we can also vectorize it
as BIT_FIELD_REF of course.