1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
|
/*
* Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
* Copyright (c) 1996-1999 by Silicon Graphics. All rights reserved.
* Copyright (c) 2003-2011 Hewlett-Packard Development Company, L.P.
*
*
* THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
* OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
*
* Permission is hereby granted to use or copy this program
* for any purpose, provided the above notices are retained on all copies.
* Permission to modify the code and to distribute modified code is granted,
* provided the above notices are retained, and a notice that the code was
* modified is included with the above copyright notice.
*
*/
/* The following implementation assumes GCC 4.7 or later. */
/* For the details, see GNU Manual, chapter 6.52 (Built-in functions */
/* for memory model aware atomic operations). */
#if defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_1) \
|| defined(AO_GCC_FORCE_HAVE_CAS)
# define AO_GCC_HAVE_char_SYNC_CAS
#endif
#if (__SIZEOF_SHORT__ == 2 && defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_2)) \
|| defined(AO_GCC_FORCE_HAVE_CAS)
# define AO_GCC_HAVE_short_SYNC_CAS
#endif
#if (__SIZEOF_INT__ == 4 && defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4)) \
|| (__SIZEOF_INT__ == 8 && defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_8)) \
|| defined(AO_GCC_FORCE_HAVE_CAS)
# define AO_GCC_HAVE_int_SYNC_CAS
#endif
#if (__SIZEOF_SIZE_T__ == 4 && defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4)) \
|| (__SIZEOF_SIZE_T__ == 8 \
&& defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_8)) \
|| defined(AO_GCC_FORCE_HAVE_CAS)
# define AO_GCC_HAVE_SYNC_CAS
#endif
#ifdef AO_UNIPROCESSOR
/* If only a single processor (core) is used, AO_UNIPROCESSOR could */
/* be defined by the client to avoid unnecessary memory barrier. */
AO_INLINE void
AO_nop_full(void)
{
AO_compiler_barrier();
}
# define AO_HAVE_nop_full
#else
AO_INLINE void
AO_nop_read(void)
{
__atomic_thread_fence(__ATOMIC_ACQUIRE);
}
# define AO_HAVE_nop_read
# ifndef AO_HAVE_nop_write
AO_INLINE void
AO_nop_write(void)
{
__atomic_thread_fence(__ATOMIC_RELEASE);
}
# define AO_HAVE_nop_write
# endif
AO_INLINE void
AO_nop_full(void)
{
/* __sync_synchronize() could be used instead. */
__atomic_thread_fence(__ATOMIC_SEQ_CST);
}
# define AO_HAVE_nop_full
#endif /* !AO_UNIPROCESSOR */
#include "generic-small.h"
#ifndef AO_PREFER_GENERALIZED
# include "generic-arithm.h"
AO_INLINE AO_TS_VAL_t
AO_test_and_set(volatile AO_TS_t *addr)
{
return (AO_TS_VAL_t)__atomic_test_and_set(addr, __ATOMIC_RELAXED);
}
# define AO_HAVE_test_and_set
AO_INLINE AO_TS_VAL_t
AO_test_and_set_acquire(volatile AO_TS_t *addr)
{
return (AO_TS_VAL_t)__atomic_test_and_set(addr, __ATOMIC_ACQUIRE);
}
# define AO_HAVE_test_and_set_acquire
AO_INLINE AO_TS_VAL_t
AO_test_and_set_release(volatile AO_TS_t *addr)
{
return (AO_TS_VAL_t)__atomic_test_and_set(addr, __ATOMIC_RELEASE);
}
# define AO_HAVE_test_and_set_release
AO_INLINE AO_TS_VAL_t
AO_test_and_set_full(volatile AO_TS_t *addr)
{
return (AO_TS_VAL_t)__atomic_test_and_set(addr, __ATOMIC_SEQ_CST);
}
# define AO_HAVE_test_and_set_full
#endif /* !AO_PREFER_GENERALIZED */
#ifdef AO_HAVE_DOUBLE_PTR_STORAGE
# if !defined(AO_HAVE_double_load) && !defined(AO_SKIPATOMIC_double_load)
AO_INLINE AO_double_t
AO_double_load(const volatile AO_double_t *addr)
{
AO_double_t result;
result.AO_whole = __atomic_load_n(&addr->AO_whole, __ATOMIC_RELAXED);
return result;
}
# define AO_HAVE_double_load
# endif
# if !defined(AO_HAVE_double_load_acquire) \
&& !defined(AO_SKIPATOMIC_double_load_acquire)
AO_INLINE AO_double_t
AO_double_load_acquire(const volatile AO_double_t *addr)
{
AO_double_t result;
result.AO_whole = __atomic_load_n(&addr->AO_whole, __ATOMIC_ACQUIRE);
return result;
}
# define AO_HAVE_double_load_acquire
# endif
# ifndef AO_HAVE_double_store
AO_INLINE void
AO_double_store(volatile AO_double_t *addr, AO_double_t value)
{
__atomic_store_n(&addr->AO_whole, value.AO_whole, __ATOMIC_RELAXED);
}
# define AO_HAVE_double_store
# endif
# ifndef AO_HAVE_double_store_release
AO_INLINE void
AO_double_store_release(volatile AO_double_t *addr, AO_double_t value)
{
__atomic_store_n(&addr->AO_whole, value.AO_whole, __ATOMIC_RELEASE);
}
# define AO_HAVE_double_store_release
# endif
# if (__SIZEOF_SIZE_T__ == 4 && defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_8)) \
|| (__SIZEOF_SIZE_T__ == 8 /* half of AO_double_t */ \
&& defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_16))
# define AO_GCC_HAVE_double_SYNC_CAS
# endif
#endif /* AO_HAVE_DOUBLE_PTR_STORAGE */
#ifdef AO_GCC_HAVE_double_SYNC_CAS
# ifndef AO_HAVE_double_compare_and_swap
AO_INLINE int
AO_double_compare_and_swap(volatile AO_double_t *addr,
AO_double_t old_val, AO_double_t new_val)
{
return (int)__atomic_compare_exchange_n(&addr->AO_whole,
&old_val.AO_whole /* p_expected */,
new_val.AO_whole /* desired */,
0 /* is_weak: false */,
__ATOMIC_RELAXED /* success */,
__ATOMIC_RELAXED /* failure */);
}
# define AO_HAVE_double_compare_and_swap
# endif
/* TODO: Add double CAS _acquire/release/full primitives. */
#endif /* AO_GCC_HAVE_double_SYNC_CAS */
|
