760a786d15
Summary: Currently, we only use `-mlink-builtin-bitcode` for non-LTO NVIDIA compiliations. This has the problem that it will internalize the RPC client symbol which needs to be visible to the host. To counteract that, I put `retain` on it, but this also prevents optimizations on the global itself, so the passes we have that remove the symbol don't work on OpenMP anymore. This patch does the dumbest solution, adding a special string check for it in clang. Not the best solution, the runner up would be to have a clang attribute for `externally_initialized` because those can't be internalized, but that might have some unfortunate side-effects. Alternatively we could make NVIDIA compilations do LTO all the time, but that would affect some users and it's harder than I thought.
The LLVM/Offload Subproject
The Offload subproject aims at providing tooling, runtimes, and APIs that allow users to execute code on accelerators or other "co-processors" that may or may not match the architecture of their "host". In the long run, all kinds of targets are in scope of this effort, including but not limited to: CPUs, GPUs, FPGAs, AI/ML accelerators, distributed resources, etc.
For OpenMP offload users, the project is ready and fully usable. The final API design is still under development. More content will show up here and on our webpage soon. In the meantime, people are encouraged to participate in our meetings (see below) and check our development board as well as the discussions on Discourse.
Meetings
Every second Wednesday, 7:00 - 8:00am PT, starting Jan 24, 2024. Alternates with the OpenMP in LLVM meeting. invite.ics Meeting Minutes and Agenda