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+/* Low-level functions for atomic operations. ARC version.
+ Copyright (C) 2012-2020 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
+
+#include <stdint.h>
+
+typedef int32_t atomic32_t;
+typedef uint32_t uatomic32_t;
+typedef int_fast32_t atomic_fast32_t;
+typedef uint_fast32_t uatomic_fast32_t;
+
+typedef intptr_t atomicptr_t;
+typedef uintptr_t uatomicptr_t;
+typedef intmax_t atomic_max_t;
+typedef uintmax_t uatomic_max_t;
+
+#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 */
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+/* Machine-specific POSIX semaphore type layouts. ARC version.
+ Copyright (C) 2002-2020 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 _SEMAPHORE_H
+# error "Never use <bits/semaphore.h> directly; include <semaphore.h> instead."
+#endif
+
+#define __SIZEOF_SEM_T 16
+
+/* Value returned if `sem_open' failed. */
+#define SEM_FAILED ((sem_t *) 0)
+
+typedef union
+{
+ char __size[__SIZEOF_SEM_T];
+ long int __align;
+} sem_t;