https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70666

            Bug ID: 70666
           Summary: SLP vectorization opportunity to use load element +
                    splat
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: wschmidt at gcc dot gnu.org
                CC: dje at gcc dot gnu.org, rguenth at gcc dot gnu.org
  Target Milestone: ---
            Target: powerpc*-unknown-linux-gnu

As discussed in PR70130, there is an opportunity to produce better code during
SLP vectorization for a vector load with a permutation vector where all
elements of the permutation are identical.  A load of the desired element and a
splat would be better than current generated code, which makes use of unaligned
loads.  See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70130#c23 for details,
and see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70130#c11 for a test case
that can be used to reproduce the pattern.

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