[X86] Improve vXi64 ISD::ABS codegen with SSE41+

Make use of vblendvpd to select on the signbit

Differential Revision: https://reviews.llvm.org/D56544

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350999 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed