Summary: Port more instructions. AMD version is at https://gist.github.com/jhuber6/235d7ee95f747c75f9a3cfd8eedac6aa
Summary: This removes the use of OpenMP offloading to build the device runtime. The main benefit here is that we no longer need to rely on offloading semantics to build a device only runtime. Things like variants are now no longer needed and can just be simple if-defs. In the future, I will remove most of the special handling here and fold it into calls to the `<gpuintrin.h>` functions instead. Additionally I will rework the compilation to make this a separate runtime. The current plan is to have this, but make including OpenMP and offloading either automatically add it, or print a warning if it's missing. This will allow us to use a normal CMake workflow and delete all the weird 'lets pull the clang binary out of the build' business. ``` -DRUNTIMES_amdgcn-amd-amdhsa_LLVM_ENABLE_RUNTIMES=offload -DLLVM_RUNTIME_TARGETS=amdgcn-amd-amdhsa ``` After that, linking the OpenMP device runtime will be `-Xoffload-linker -lomp`. I.e. no more fat binary business. Only look at the most recent commit since this includes the two dependencies (fix to AMDGPUEmitPrintfBinding and the PointerToMember bug).
https://github.com/codespell-project/codespell % `codespell --ignore-words-list=archtype,hsa,identty,inout,iself,nd,te,ths,vertexes --write-changes`
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.
Summary: We previously built this for every single architecture to deal with incompatibility. This patch updates it to use the 'generic' IR that `libc` and other projects use. Who knows if this will have any side-effects, probably worth testing more but it passes the tests I expect to pass on my side.
Summary: This is a hack that only NVPTX needs.
Summary: This patch adds an RPC interface that lives directly in the OpenMP device runtime. This allows OpenMP to implement custom opcodes. Currently this is only providing the host call interface, which is the raw version of reverse offloading. Previously this lived in `libc/` as an extension which is not the correct place. The interface here uses a weak symbol for the RPC client by the same name that the `libc` interface uses. This means that it will defer to the libc one if both are present so we don't need to set up multiple instances. The presense of this symbol is what controls whether or not we set up the RPC server. Because this is an external symbol it normally won't be optimized out, so there's a special pass in OpenMPOpt that deletes this symbol if it is unused during linking. That means at `O0` the RPC server will always be present now, but will be removed trivially if it's not used at O1 and higher.
We had three `utils::` namespaces, all with different "meaning" (host, device, hsa_utils). We should, when we can, keep "include/Shared" accessible from host and device, thus RefCountTy has been moved to a separate header. `hsa_utils` was introduced to make `utils::` less overloaded. And common functionality was de-duplicated, e.g., `utils::advance` and `utils::advanceVoidPtr` -> `utils:advancePtr`. Type punning now checks for the size of the result to make sure it matches the source type. No functional change was intended.
Summary: The 'omp_alloc' function should be callable from a target region. This patch implemets it by simply calling `malloc` for every non-default trait value allocator. All the special access modifiers are unimplemented and return null. The null allocator returns null as the spec states it should not be usable from the target.
In a nutshell, this moves our libomptarget code to populate the offload subproject. With this commit, users need to enable the new LLVM/Offload subproject as a runtime in their cmake configuration. No further changes are expected for downstream code. Tests and other components still depend on OpenMP and have also not been renamed. The results below are for a build in which OpenMP and Offload are enabled runtimes. In addition to the pure `git mv`, we needed to adjust some CMake files. Nothing is intended to change semantics. ``` ninja check-offload ``` Works with the X86 and AMDGPU offload tests ``` ninja check-openmp ``` Still works but doesn't build offload tests anymore. ``` ls install/lib ``` Shows all expected libraries, incl. - `libomptarget.devicertl.a` - `libomptarget-nvptx-sm_90.bc` - `libomptarget.rtl.amdgpu.so` -> `libomptarget.rtl.amdgpu.so.18git` - `libomptarget.so` -> `libomptarget.so.18git` Fixes: https://github.com/llvm/llvm-project/issues/75124 --------- Co-authored-by: Saiyedul Islam <Saiyedul.Islam@amd.com>