tree 413c3bbbd3b33cb5440bc8e7b024737a221d3f98
parent 5d37f6c75626db314b8dbf06231c8ffb502189fb
author Sanjay Patel <spatel@rotateright.com> 1547648118 +0000
committer Sanjay Patel <spatel@rotateright.com> 1547648118 +0000

[x86] lower shuffle of extracts to AVX2 vperm instructions

I was trying to prevent shuffle regressions while matching more horizontal ops 
and ended up here:
  shuf (extract X, 0), (extract X, 4), Mask --> extract (shuf X, undef, Mask'), 0

The affected tests were added for:
https://bugs.llvm.org/show_bug.cgi?id=34380

This patch won't change the examples in the bug report itself, but we should be 
able to extend this to catch more types.

Differential Revision: https://reviews.llvm.org/D56756


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351346 91177308-0d34-0410-b5e6-96231b3b80d8