AMDGPU: Add llvm.amdgcn.ds.ordered.add & swap

Reviewers: arsenm, nhaehnle

Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits

Differential Revision: https://reviews.llvm.org/D52944

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351351 91177308-0d34-0410-b5e6-96231b3b80d8
15 files changed