https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113213
--- Comment #1 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Andrew Stubbs <[email protected]>: https://gcc.gnu.org/g:a53c5c42c6c3c28275b79a8c29883f7a5ee754c0 commit r16-7258-ga53c5c42c6c3c28275b79a8c29883f7a5ee754c0 Author: Andrew Stubbs <[email protected]> Date: Mon Dec 8 16:18:02 2025 +0000 libgomp, amdgcn, nvptx: Improve omp_target_is_accessible [PR121813] This patch extends omp_target_is_accessible to check the actual device status for the memory region, on amdgcn and nvptx devices (rather than just checking if shared memory is enabled). In both cases, we check the status of each 4k region within the given memory range (assuming 4k pages should be safe for all the currently supported hosts) and returns true if all of the pages report accessible. The testcases have been modified to check that allocations marked accessible actually are accessible (inaccessibility can't be checked without invoking memory faults), and to understand that some parts of an array can be accessible but other parts not (I have observed this intermittently for the stack memory on amdgcn using the Fortran testcase, which can have the allocation span pages). There's also new testcases for the various other memory modes, and for managed memory. include/ChangeLog: * cuda/cuda.h (CUpointer_attribute): New enum. (cuPointerGetAttribute): New prototype. libgomp/ChangeLog: PR libgomp/121813 PR libgomp/113213 * libgomp-plugin.h (GOMP_OFFLOAD_is_accessible_ptr): New prototype. * libgomp.h (struct gomp_device_descr): Add GOMP_OFFLOAD_is_accessible_ptr. * libgomp.texi: Update omp_target_is_accessible docs. * plugin/cuda-lib.def (cuPointerGetAttribute): New entry. * plugin/plugin-gcn.c (struct hsa_runtime_fn_info): Add hsa_amd_svm_attributes_get_fn and hsa_amd_pointer_info_fn. (init_hsa_runtime_functions): Add hsa_amd_svm_attributes_get and hsa_amd_pointer_info. (enum accessible): New enum type. (host_memory_is_accessible): New function. (device_memory_is_accessible): New function. (GOMP_OFFLOAD_is_accessible_ptr): New function. * plugin/plugin-nvptx.c (GOMP_OFFLOAD_is_accessible_ptr): Likewise. * target.c (omp_target_is_accessible): Call is_accessible_ptr_func. (gomp_load_plugin_for_device): Add is_accessible_ptr. * testsuite/libgomp.c-c++-common/target-is-accessible-1.c: Rework to match more details of the GPU implementation. * testsuite/libgomp.fortran/target-is-accessible-1.f90: Likewise. * testsuite/libgomp.c-c++-common/target-is-accessible-2.c: New test. * testsuite/libgomp.c-c++-common/target-is-accessible-3.c: New test. * testsuite/libgomp.c-c++-common/target-is-accessible-4.c: New test. * testsuite/libgomp.c-c++-common/target-is-accessible-5.c: New test.
