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AC_DEFUN([SIMPLEOPS_CHECK_ATOMIC_OP_NEEDS_MEMORY_BARRIER],
[dnl
AC_CANONICAL_HOST
AC_CACHE_CHECK([whether atomic ops require a memory barrier],
[simpleops_cv_atomic_op_needs_memory_barrier],
[dnl
case $host_cpu in
i?86) simpleops_cv_atomic_op_needs_memory_barrier="no" ;;
x86_64) simpleops_cv_atomic_op_needs_memory_barrier="no" ;;
arm*) simpleops_cv_atomic_op_needs_memory_barrier="no" ;;
*) simpleops_cv_atomic_op_needs_memory_barrier="yes" ;;
esac
])
if test "x$simpleops_cv_atomic_op_needs_memory_barrier" = "xyes"; then
AC_DEFINE(ATOMIC_OP_NEEDS_MEMORY_BARRIER, 1,
[Define to 1 if memory barriers are needed around atomic operations.])
fi
])
AC_DEFUN([SIMPLEOPS_CHECK_NATIVE_ATOMIC_PRIMITIVES],
[dnl
SIMPLEOPS_CHECK_ATOMIC_OP_NEEDS_MEMORY_BARRIER
AC_CACHE_CHECK([for native atomic primitives], simpleops_cv_native_atomic_primitives,
[dnl
AC_TRY_LINK([
static int test_atomic (void)
{
int r, x;
#if SIMPLEOPS_ATOMIC_NEEDS_MEMORY_BARRIER
__sync_synchronize ();
#endif
x = 0;
r = __sync_fetch_and_add (&x, 1);
r |= __sync_bool_compare_and_swap (&x, 0, 1);
}
],
[test_atomic ()],
[simpleops_cv_native_atomic_primitives="yes"],
[simpleops_cv_native_atomic_primitives="no"]
)
])
if test "x$simpleops_cv_native_atomic_primitives" = "xyes"; then
AC_DEFINE(HAVE_NATIVE_ATOMIC_PRIMITIVES, 1,
[Define to 1 if your compiler supports the __sync_* atomic primitives])
fi
])
AC_DEFUN([SIMPLEOPS_CHECK_NATIVE_ATOMIC_SWAP],
[dnl
AC_CACHE_CHECK([for native atomic swap], simpleops_cv_native_atomic_swap,
[dnl
AC_TRY_LINK([
static int test_atomic_swap (void)
{
int r, x;
x = 0;
r = __sync_swap (&x, 1);
}
],
[test_atomic_swap ()],
[simpleops_cv_native_atomic_swap="yes"],
[simpleops_cv_native_atomic_swap="no"]
)
])
if test "x$simpleops_cv_native_atomic_swap" = "xyes"; then
AC_DEFINE(HAVE_NATIVE_ATOMIC_SWAP, 1,
[Define to 1 if your compiler supports __sync_swap()])
fi
])
AC_DEFUN([SIMPLEOPS_CHECK_ATOMIC],
[dnl
AC_ARG_ENABLE([atomic],
[AS_HELP_STRING([--disable-atomic], [disable atomic operations])],
[AC_DEFINE(DISABLE_ATOMIC, 1, [Define to 1 to disable atomic operations.])]
)
SIMPLEOPS_CHECK_NATIVE_ATOMIC_PRIMITIVES
SIMPLEOPS_CHECK_NATIVE_ATOMIC_SWAP
AC_CHECK_HEADERS([libkern/OSAtomic.h atomic_ops.h])
])
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