As per OpenMP 5.1, we need to assume that when the lookup for
`use_device_ptr/addr` fails, the incoming pointer was already device
accessible.
Prior to 5.1, a lookup-failure meant a user-error (for
`use_device_ptr`),
so we could do anything in that scenario. For `use_device_addr`,
it was always incorrect to set the address to null.
OpenMP 6.1 adds a way to retain the previous behavior of nullifying a
pointer
when the lookup fails. That will be tackled by the PR stack
starting with https://github.com/llvm/llvm-project/pull/169603.
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