commit 17aff39d1c094a8237fe01b5bbecc55507c632f4
author Craig Topper <craig.topper@intel.com> Mon Apr 15 17:17:35 2019 +0000
committer Copybara-Service <copybara-worker@google.com> Sun Oct 18 01:26:39 2020 -0700
tree e3f380a2bf2fe4d99922a34c2fe272b6f75dd41e
parent c8a226c02f176e63b766da6aff72cfc415749f03

[X86] Restore the pavg intrinsics.

The pattern we replaced these with may be too hard to match as demonstrated by
PR41496 and PR41316.

This patch restores the intrinsics and then we can start focusing
on the optimizing the intrinsics.

I've mostly reverted the original patch that removed them. Though I modified
the avx512 intrinsics to not have masking built in.

Differential Revision: https://reviews.llvm.org/D60674

llvm-svn: 358427
GitOrigin-RevId: 8e364c680fab1724bd0d4749b8d1177843164aa7