glibc/sysdeps/ia64/atomic-machine.h

/* Copyright (C) 2003-2022 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/>.  */

#include <ia64intrin.h>

#define __HAVE_64B_ATOMICS 1
#define USE_ATOMIC_COMPILER_BUILTINS 0

/* XXX Is this actually correct?  */
#define ATOMIC_EXCHANGE_USES_CAS 0


#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_32_acq(mem, newval, oldval) \
  (!__sync_bool_compare_and_swap ((mem), (int) (long) (oldval), \
				  (int) (long) (newval)))

#define __arch_compare_and_exchange_bool_64_acq(mem, newval, oldval) \
  (!__sync_bool_compare_and_swap ((mem), (long) (oldval), \
				  (long) (newval)))

#define __arch_compare_and_exchange_val_8_acq(mem, newval, oldval) \
  (abort (), (__typeof (*mem)) 0)

#define __arch_compare_and_exchange_val_16_acq(mem, newval, oldval) \
  (abort (), (__typeof (*mem)) 0)

#define __arch_compare_and_exchange_val_32_acq(mem, newval, oldval) \
  __sync_val_compare_and_swap ((mem), (int) (long) (oldval), \
			       (int) (long) (newval))

#define __arch_compare_and_exchange_val_64_acq(mem, newval, oldval) \
  __sync_val_compare_and_swap ((mem), (long) (oldval), (long) (newval))

/* Atomically store newval and return the old value.  */
#define atomic_exchange_acq(mem, value) \
  __sync_lock_test_and_set (mem, value)

#define atomic_exchange_rel(mem, value) \
  (__sync_synchronize (), __sync_lock_test_and_set (mem, value))

#define atomic_exchange_and_add(mem, value) \
  __sync_fetch_and_add ((mem), (value))

#define atomic_decrement_if_positive(mem) \
  ({ __typeof (*mem) __oldval, __val;					      \
     __typeof (mem) __memp = (mem);					      \
									      \
     __val = (*__memp);							      \
     do									      \
       {								      \
	 __oldval = __val;						      \
	 if (__builtin_expect (__val <= 0, 0))				      \
	   break;							      \
	 __val = atomic_compare_and_exchange_val_acq (__memp,	__oldval - 1, \
						      __oldval);	      \
       }								      \
     while (__builtin_expect (__val != __oldval, 0));			      \
     __oldval; })

#define atomic_bit_test_set(mem, bit) \
  ({ __typeof (*mem) __oldval, __val;					      \
     __typeof (mem) __memp = (mem);					      \
     __typeof (*mem) __mask = ((__typeof (*mem)) 1 << (bit));		      \
									      \
     __val = (*__memp);							      \
     do									      \
       {								      \
	 __oldval = __val;						      \
	 __val = atomic_compare_and_exchange_val_acq (__memp,		      \
						      __oldval | __mask,      \
						      __oldval);	      \
       }								      \
     while (__builtin_expect (__val != __oldval, 0));			      \
     __oldval & __mask; })

#define atomic_full_barrier() __sync_synchronize ()