https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96898
--- Comment #9 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Tom de Vries <vr...@gcc.gnu.org>: https://gcc.gnu.org/g:15545563128f0240192c263522d4a36b7f86250f commit r11-3145-g15545563128f0240192c263522d4a36b7f86250f Author: Tom de Vries <tdevr...@suse.de> Date: Mon Sep 7 10:47:25 2020 +0200 [libatomic] Add nvptx support Add nvptx support to libatomic. Given that atomic_test_and_set is not implemented for nvptx (PR96964), the compiler translates __atomic_test_and_set falling back onto the "Failing all else, assume a single threaded environment and simply perform the operation" case in expand_atomic_test_and_set, so it doesn't map onto an actual atomic operation. Still, that counts as supported for the configure test of libatomic, so we end up with HAVE_ATOMIC_TAS_1/2/4/8/16 == 1, and the corresponding __atomic_test_and_set_1/2/4/8/16 in libatomic all using that non-atomic implementation. Fix this by adding an atomic_test_and_set expansion for nvptx, that uses libatomics __atomic_test_and_set_1. This again makes the configure tests for HAVE_ATOMIC_TAS_1/2/4/8/16 fail, so instead we use this case in tas_n.c: ... /* If this type is smaller than word-sized, fall back to a word-sized compare-and-swap loop. */ bool SIZE(libat_test_and_set) (UTYPE *mptr, int smodel) ... which for __atomic_test_and_set_8 uses INVERT_MASK_8. Add INVERT_MASK_8 in libatomic_i.h, as well as MASK_8. Tested libatomic testsuite on nvptx. gcc/ChangeLog: PR target/96964 * config/nvptx/nvptx.md (define_expand "atomic_test_and_set"): New expansion. libatomic/ChangeLog: PR target/96898 * configure.tgt: Add nvptx. * libatomic_i.h (MASK_8, INVERT_MASK_8): New macro definition. * config/nvptx/host-config.h: New file. * config/nvptx/lock.c: New file.
