gcc/libgomp/config
Andrew Stubbs 62174ec27b openmp, nvptx: ompx_gnu_managed_mem_alloc
This adds support for using Cuda Managed Memory with omp_alloc.  AMD support
will be added in a future patch.

There is one new predefined allocator, "ompx_gnu_managed_mem_alloc", plus a
corresponding memory space, which can be used to allocate memory in the
"managed" space.

The nvptx plugin is modified to make the necessary Cuda calls, via two new
(optional) plugin interfaces.

gcc/fortran/ChangeLog:

	* openmp.cc (is_predefined_allocator): Use GOMP_OMP_PREDEF_ALLOC_MAX
	and GOMP_OMPX_PREDEF_ALLOC_MIN/MAX instead of hardcoded values in the
	comment.

include/ChangeLog:

	* cuda/cuda.h (cuMemAllocManaged): Add declaration and related
	CU_MEM_ATTACH_GLOBAL flag.
	* gomp-constants.h (GOMP_OMPX_PREDEF_ALLOC_MAX): Update to 201.
	(GOMP_OMP_PREDEF_MEMSPACE_MAX): New constant.
	(GOMP_OMPX_PREDEF_MEMSPACE_MIN): New constant.
	(GOMP_OMPX_PREDEF_MEMSPACE_MAX): New constant.

libgomp/ChangeLog:

	* allocator.c (ompx_gnu_max_predefined_alloc): Update to
	ompx_gnu_managed_mem_alloc.
	(_Static_assert): Fix assertion messages for allocators and add
	new assertions for memspace constants.
	(omp_max_predefined_mem_space): New define.
	(ompx_gnu_min_predefined_mem_space): New define.
	(ompx_gnu_max_predefined_mem_space): New define.
	(MEMSPACE_ALLOC): Add check for non-standard memspaces.
	(MEMSPACE_CALLOC): Likewise.
	(MEMSPACE_REALLOC): Likewise.
	(MEMSPACE_VALIDATE): Likewise.
	(predefined_ompx_gnu_alloc_mapping): Add ompx_gnu_managed_mem_space.
	(omp_init_allocator): Add ompx_gnu_managed_mem_space validation.
	* config/gcn/allocator.c (gcn_memspace_alloc): Add check for
	non-standard memspaces.
	(gcn_memspace_calloc): Likewise.
	(gcn_memspace_realloc): Likewise.
	(gcn_memspace_validate): Update to validate standard vs non-standard
	memspaces.
	* config/linux/allocator.c (linux_memspace_alloc): Add managed
	memory space handling.
	(linux_memspace_calloc): Likewise.
	(linux_memspace_free): Likewise.
	(linux_memspace_realloc): Likewise (returns NULL for fallback).
	* config/nvptx/allocator.c (nvptx_memspace_alloc): Add check for
	non-standard memspaces.
	(nvptx_memspace_calloc): Likewise.
	(nvptx_memspace_realloc): Likewise.
	(nvptx_memspace_validate): Update to validate standard vs non-standard
	memspaces.
	* env.c (parse_allocator): Add ompx_gnu_managed_mem_alloc,
	ompx_gnu_managed_mem_space, and some static asserts so I don't forget
	them again.
	* libgomp-plugin.h (GOMP_OFFLOAD_managed_alloc): New declaration.
	(GOMP_OFFLOAD_managed_free): New declaration.
	* libgomp.h (gomp_managed_alloc): New declaration.
	(gomp_managed_free): New declaration.
	(struct gomp_device_descr): Add managed_alloc_func and
	managed_free_func fields.
	* libgomp.texi: Document ompx_gnu_managed_mem_alloc and
	ompx_gnu_managed_mem_space, add C++ template documentation, and
	describe NVPTX and AMD support.
	* omp.h.in: Add ompx_gnu_managed_mem_space and
	ompx_gnu_managed_mem_alloc enumerators, and gnu_managed_mem C++
	allocator template.
	* omp_lib.f90.in: Add Fortran bindings for new allocator and
	memory space.
	* omp_lib.h.in: Likewise.
	* plugin/cuda-lib.def: Add cuMemAllocManaged.
	* plugin/plugin-nvptx.c (nvptx_alloc): Add managed parameter to
	support cuMemAllocManaged.
	(GOMP_OFFLOAD_alloc): Move contents to ...
	(cleanup_and_alloc): ... this new function, and add managed support.
	(GOMP_OFFLOAD_managed_alloc): New function.
	(GOMP_OFFLOAD_managed_free): New function.
	* target.c (gomp_managed_alloc): New function.
	(gomp_managed_free): New function.
	(gomp_load_plugin_for_device): Load optional managed_alloc
	and managed_free plugin APIs.
	* testsuite/lib/libgomp.exp: Add check_effective_target_omp_managedmem.
	* testsuite/libgomp.c++/alloc-managed-1.C: New test.
	* testsuite/libgomp.c/alloc-managed-1.c: New test.
	* testsuite/libgomp.c/alloc-managed-2.c: New test.
	* testsuite/libgomp.c/alloc-managed-3.c: New test.
	* testsuite/libgomp.c/alloc-managed-4.c: New test.
	* testsuite/libgomp.fortran/alloc-managed-1.f90: New test.

Co-authored-by: Kwok Cheung Yeung <kcyeung@baylibre.com>
Co-authored-by: Thomas Schwinge <tschwinge@baylibre.com>
2025-11-13 14:16:09 +00:00
..
accel
bsd
darwin
gcn openmp, nvptx: ompx_gnu_managed_mem_alloc 2025-11-13 14:16:09 +00:00
hpux
linux openmp, nvptx: ompx_gnu_managed_mem_alloc 2025-11-13 14:16:09 +00:00
mingw32
nvptx openmp, nvptx: ompx_gnu_managed_mem_alloc 2025-11-13 14:16:09 +00:00
posix
rtems
t-aix