[X86] Auto upgrade XOP/AVX512 rotation intrinsics to generic funnel shift intrinsics (llvm)

This emits FSHL/FSHR generic intrinsics for the XOP VPROT and AVX512 VPROL/VPROR rotation intrinsics.

Clang counterpart: https://reviews.llvm.org/D55937

Differential Revision: https://reviews.llvm.org/D55938

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349795 91177308-0d34-0410-b5e6-96231b3b80d8
12 files changed