[PATCH] D18644: [SystemZ] Support ATOMIC_FENCE

[Ulrich Weigand via llvm-commits]

uweigand added a comment.

This seems overly conservative: I think we only need a BCR serialization instruction for sequentially-consistent cross-thread fences.  For everything else, a pure compiler barrier should be sufficient.  See e.g. the X86 back-end for how to implement that check.


http://reviews.llvm.org/D18644