glibc/sysdeps/arc/atomic-machine.h

58 lines
2.4 KiB
C

/* Low-level functions for atomic operations. ARC version.
Copyright (C) 2020-2024 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library. If not, see
<https://www.gnu.org/licenses/>. */
#ifndef _ARC_BITS_ATOMIC_H
#define _ARC_BITS_ATOMIC_H 1
#define __HAVE_64B_ATOMICS 0
#define USE_ATOMIC_COMPILER_BUILTINS 1
/* ARC does have legacy atomic EX reg, [mem] instruction but the micro-arch
is not as optimal as LLOCK/SCOND specially for SMP. */
#define ATOMIC_EXCHANGE_USES_CAS 1
#define __arch_compare_and_exchange_bool_8_acq(mem, newval, oldval) \
(abort (), 0)
#define __arch_compare_and_exchange_bool_16_acq(mem, newval, oldval) \
(abort (), 0)
#define __arch_compare_and_exchange_bool_64_acq(mem, newval, oldval) \
(abort (), 0)
#define __arch_compare_and_exchange_val_8_int(mem, newval, oldval, model) \
(abort (), (__typeof (*mem)) 0)
#define __arch_compare_and_exchange_val_16_int(mem, newval, oldval, model) \
(abort (), (__typeof (*mem)) 0)
#define __arch_compare_and_exchange_val_64_int(mem, newval, oldval, model) \
(abort (), (__typeof (*mem)) 0)
#define __arch_compare_and_exchange_val_32_int(mem, newval, oldval, model) \
({ \
typeof (*mem) __oldval = (oldval); \
__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, \
model, __ATOMIC_RELAXED); \
__oldval; \
})
#define atomic_compare_and_exchange_val_acq(mem, new, old) \
__atomic_val_bysize (__arch_compare_and_exchange_val, int, \
mem, new, old, __ATOMIC_ACQUIRE)
#define atomic_full_barrier() ({ asm volatile ("dmb 3":::"memory"); })
#endif /* _ARC_BITS_ATOMIC_H */