Clang 3.6 Will Hopefully Have OpenMP Support

OpenMP support within LLVM/Clang has been a long time coming but hopefully for the next release -- LLVM 3.6 -- there could finally be out-of-the-box Clang OpenMP support.

Intel's compiler team in Russia has largely been leading the Clang OpenMP work and maintaining an out-of-tree Clang-OMP repository for staging all of their patches. Talk of OpenMP on Clang has gone back years with other developers also working towards supporting this parallel programming interface. Earlier this year I tested out Intel's latest Clang-OMP code at the time and it was working out well and is certainly beneficial to the performance of any scientific applications using OpenMP.

While an extensive road-map for landing Clang OpenMP hasn't been clear, Alexey Bataev of Intel has signaled that it could happen for the LLVM 3.6 release that's likely to come out in early 2015.

Alexey wrote in response to a mailing list question, a status update, "We have implemented "omp parallel" with almost all clauses (except for reduction() that I'm working on right now) + "omp for simd". Currently we have several patches for "omp for" and several other constructs, like "flush", "atomic" etc. We did not started work on tasks yet. We hope to complete OpenMP to 3.6 release, but it depends mostly on code review speed."

Other interesting LLVM development news from the past week can also be found via LLVM Weekly.