These intrinsics are used by MSVC's header files on AArch64 Windows as
well as AArch32, so we should support them for both targets. I've
factored them out of CodeGenFunction::EmitARMBuiltinExpr into separate
functions that EmitAArch64BuiltinExpr can call as well.
Reviewers: javed.absar, mstorsjo
Reviewed By: mstorsjo
Subscribers: kristof.beyls, cfe-commits
Differential Revision: https://reviews.llvm.org/D47476
llvm-svn: 333513