diff --git a/openmp/docs/ReleaseNotes.rst b/openmp/docs/ReleaseNotes.rst --- a/openmp/docs/ReleaseNotes.rst +++ b/openmp/docs/ReleaseNotes.rst @@ -7,7 +7,7 @@ These are in-progress notes for the upcoming LLVM 12.0.0 release. Release notes for previous releases can be found on `the Download Page `_. - + Introduction ============ @@ -44,3 +44,27 @@ ``LIBOMPTARGET_INFO`` allows the user to request certain information from the ``libomptarget`` runtime using a 32-bit field. A full description of each environment variable is described :ref:`here `. + +- ``target nowait`` was supported via hidden helper task, which is a task not + bound to any parallel region. A hidden helper team with a number of threads is + created when the first hidden helper task is encountered. The number of threads + can be configured via the environment variable + ``LIBOMP_NUM_HIDDEN_HELPER_THREADS``. By default it is 8. If + ``LIBOMP_NUM_HIDDEN_HELPER_THREADS=0``, hidden helper task is disabled and + falls back to a regular OpenMP task. It can also be disabled by setting the + environment variable ``LIBOMP_USE_HIDDEN_HELPER_TASK=OFF``. + +- ``deviceRTLs`` for NVPTX platform is CUDA free now. It is generally OpenMP code. + Target dependent parts are implemented with Clang/LLVM/NVVM intrinsics. CUDA + SDK is also dropped as a dependence to build the device runtime, which means + device runtime can also be built on a CUDA free system. However, it is + disabled by default. Set the CMake variable + ``LIBOMPTARGET_BUILD_NVPTX_BCLIB=ON`` to enable the build of NVPTX device + runtime on a CUDA free system. ``gcc-multilib`` and ``g++-multilib`` are + required. If CUDA is found, the device runtime will be built by default. + + - Static NVPTX device runtime library (``libomptarget-nvptx.a``) was dropped. + A bitcode library is required to build an OpenMP program. If the library is + not found in the default path or any of the paths defined by ``LIBRARY_PATH``, + an error will be raised. User can also specify the path to the bitcode device + library via ``--libomptarget-nvptx-bc-path=``.