1 /*
2  * Distributed under the Boost Software License, Version 1.0.
3  * (See accompanying file LICENSE_1_0.txt or copy at
4  * http://www.boost.org/LICENSE_1_0.txt)
5  *
6  * Copyright (c) 2014 Andrey Semashev
7  */
8 /*!
9  * \file   atomic/detail/ops_gcc_atomic.hpp
10  *
11  * This header contains implementation of the \c operations template.
12  */
13 
14 #ifndef BOOST_ATOMIC_DETAIL_OPS_GCC_ATOMIC_HPP_INCLUDED_
15 #define BOOST_ATOMIC_DETAIL_OPS_GCC_ATOMIC_HPP_INCLUDED_
16 
17 #include <boost/memory_order.hpp>
18 #include <boost/atomic/detail/config.hpp>
19 #include <boost/atomic/detail/storage_type.hpp>
20 #include <boost/atomic/detail/operations_fwd.hpp>
21 #include <boost/atomic/capabilities.hpp>
22 #if defined(__clang__) && (defined(BOOST_ATOMIC_DETAIL_X86_HAS_CMPXCHG8B) || defined(BOOST_ATOMIC_DETAIL_X86_HAS_CMPXCHG16B))
23 #include <boost/atomic/detail/ops_gcc_x86_dcas.hpp>
24 #include <boost/atomic/detail/ops_cas_based.hpp>
25 #endif
26 
27 #if __GCC_ATOMIC_LLONG_LOCK_FREE != BOOST_ATOMIC_LLONG_LOCK_FREE || __GCC_ATOMIC_LONG_LOCK_FREE != BOOST_ATOMIC_LONG_LOCK_FREE ||\
28     __GCC_ATOMIC_INT_LOCK_FREE != BOOST_ATOMIC_INT_LOCK_FREE || __GCC_ATOMIC_SHORT_LOCK_FREE != BOOST_ATOMIC_SHORT_LOCK_FREE ||\
29     __GCC_ATOMIC_CHAR_LOCK_FREE != BOOST_ATOMIC_CHAR_LOCK_FREE || __GCC_ATOMIC_BOOL_LOCK_FREE != BOOST_ATOMIC_BOOL_LOCK_FREE ||\
30     __GCC_ATOMIC_WCHAR_T_LOCK_FREE != BOOST_ATOMIC_WCHAR_T_LOCK_FREE
31 // There are platforms where we need to use larger storage types
32 #include <boost/atomic/detail/int_sizes.hpp>
33 #include <boost/atomic/detail/ops_extending_cas_based.hpp>
34 #endif
35 
36 #ifdef BOOST_HAS_PRAGMA_ONCE
37 #pragma once
38 #endif
39 
40 #if defined(__INTEL_COMPILER)
41 // This is used to suppress warning #32013 described below for Intel Compiler.
42 // In debug builds the compiler does not inline any functions, so basically
43 // every atomic function call results in this warning. I don't know any other
44 // way to selectively disable just this one warning.
45 #pragma system_header
46 #endif
47 
48 namespace boost {
49 namespace atomics {
50 namespace detail {
51 
52 /*!
53  * The function converts \c boost::memory_order values to the compiler-specific constants.
54  *
55  * NOTE: The intention is that the function is optimized away by the compiler, and the
56  *       compiler-specific constants are passed to the intrinsics. I know constexpr doesn't
57  *       work in this case because the standard atomics interface require memory ordering
58  *       constants to be passed as function arguments, at which point they stop being constexpr.
59  *       However it is crucial that the compiler sees constants and not runtime values,
60  *       because otherwise it just ignores the ordering value and always uses seq_cst.
61  *       This is the case with Intel C++ Compiler 14.0.3 (Composer XE 2013 SP1, update 3) and
62  *       gcc 4.8.2. Intel Compiler issues a warning in this case:
63  *
64  *       warning #32013: Invalid memory order specified. Defaulting to seq_cst memory order.
65  *
66  *       while gcc acts silently.
67  *
68  *       To mitigate the problem ALL functions, including the atomic<> members must be
69  *       declared with BOOST_FORCEINLINE. In this case the compilers are able to see that
70  *       all functions are called with constant orderings and call intrinstcts properly.
71  *
72  *       Unfortunately, this still doesn't work in debug mode as the compiler doesn't
73  *       inline functions even when marked with BOOST_FORCEINLINE. In this case all atomic
74  *       operaions will be executed with seq_cst semantics.
75  */
convert_memory_order_to_gcc(memory_order order)76 BOOST_FORCEINLINE BOOST_CONSTEXPR int convert_memory_order_to_gcc(memory_order order) BOOST_NOEXCEPT
77 {
78     return (order == memory_order_relaxed ? __ATOMIC_RELAXED : (order == memory_order_consume ? __ATOMIC_CONSUME :
79         (order == memory_order_acquire ? __ATOMIC_ACQUIRE : (order == memory_order_release ? __ATOMIC_RELEASE :
80         (order == memory_order_acq_rel ? __ATOMIC_ACQ_REL : __ATOMIC_SEQ_CST)))));
81 }
82 
83 template< typename T >
84 struct gcc_atomic_operations
85 {
86     typedef T storage_type;
87 
storeboost::atomics::detail::gcc_atomic_operations88     static BOOST_FORCEINLINE void store(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
89     {
90         __atomic_store_n(&storage, v, atomics::detail::convert_memory_order_to_gcc(order));
91     }
92 
loadboost::atomics::detail::gcc_atomic_operations93     static BOOST_FORCEINLINE storage_type load(storage_type const volatile& storage, memory_order order) BOOST_NOEXCEPT
94     {
95         return __atomic_load_n(&storage, atomics::detail::convert_memory_order_to_gcc(order));
96     }
97 
fetch_addboost::atomics::detail::gcc_atomic_operations98     static BOOST_FORCEINLINE storage_type fetch_add(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
99     {
100         return __atomic_fetch_add(&storage, v, atomics::detail::convert_memory_order_to_gcc(order));
101     }
102 
fetch_subboost::atomics::detail::gcc_atomic_operations103     static BOOST_FORCEINLINE storage_type fetch_sub(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
104     {
105         return __atomic_fetch_sub(&storage, v, atomics::detail::convert_memory_order_to_gcc(order));
106     }
107 
exchangeboost::atomics::detail::gcc_atomic_operations108     static BOOST_FORCEINLINE storage_type exchange(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
109     {
110         return __atomic_exchange_n(&storage, v, atomics::detail::convert_memory_order_to_gcc(order));
111     }
112 
compare_exchange_strongboost::atomics::detail::gcc_atomic_operations113     static BOOST_FORCEINLINE bool compare_exchange_strong(
114         storage_type volatile& storage, storage_type& expected, storage_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT
115     {
116         return __atomic_compare_exchange_n
117         (
118             &storage, &expected, desired, false,
119             atomics::detail::convert_memory_order_to_gcc(success_order),
120             atomics::detail::convert_memory_order_to_gcc(failure_order)
121         );
122     }
123 
compare_exchange_weakboost::atomics::detail::gcc_atomic_operations124     static BOOST_FORCEINLINE bool compare_exchange_weak(
125         storage_type volatile& storage, storage_type& expected, storage_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT
126     {
127         return __atomic_compare_exchange_n
128         (
129             &storage, &expected, desired, true,
130             atomics::detail::convert_memory_order_to_gcc(success_order),
131             atomics::detail::convert_memory_order_to_gcc(failure_order)
132         );
133     }
134 
fetch_andboost::atomics::detail::gcc_atomic_operations135     static BOOST_FORCEINLINE storage_type fetch_and(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
136     {
137         return __atomic_fetch_and(&storage, v, atomics::detail::convert_memory_order_to_gcc(order));
138     }
139 
fetch_orboost::atomics::detail::gcc_atomic_operations140     static BOOST_FORCEINLINE storage_type fetch_or(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
141     {
142         return __atomic_fetch_or(&storage, v, atomics::detail::convert_memory_order_to_gcc(order));
143     }
144 
fetch_xorboost::atomics::detail::gcc_atomic_operations145     static BOOST_FORCEINLINE storage_type fetch_xor(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
146     {
147         return __atomic_fetch_xor(&storage, v, atomics::detail::convert_memory_order_to_gcc(order));
148     }
149 
test_and_setboost::atomics::detail::gcc_atomic_operations150     static BOOST_FORCEINLINE bool test_and_set(storage_type volatile& storage, memory_order order) BOOST_NOEXCEPT
151     {
152         return __atomic_test_and_set(&storage, atomics::detail::convert_memory_order_to_gcc(order));
153     }
154 
clearboost::atomics::detail::gcc_atomic_operations155     static BOOST_FORCEINLINE void clear(storage_type volatile& storage, memory_order order) BOOST_NOEXCEPT
156     {
157         __atomic_clear(const_cast< storage_type* >(&storage), atomics::detail::convert_memory_order_to_gcc(order));
158     }
159 
is_lock_freeboost::atomics::detail::gcc_atomic_operations160     static BOOST_FORCEINLINE bool is_lock_free(storage_type const volatile& storage) BOOST_NOEXCEPT
161     {
162         return __atomic_is_lock_free(sizeof(storage_type), &storage);
163     }
164 };
165 
166 #if BOOST_ATOMIC_INT128_LOCK_FREE > 0
167 #if defined(__clang__) && defined(BOOST_ATOMIC_DETAIL_X86_HAS_CMPXCHG16B)
168 
169 // Workaround for clang bug: http://llvm.org/bugs/show_bug.cgi?id=19149
170 // Clang 3.4 does not implement 128-bit __atomic* intrinsics even though it defines __GCC_HAVE_SYNC_COMPARE_AND_SWAP_16
171 template< bool Signed >
172 struct operations< 16u, Signed > :
173     public cas_based_operations< gcc_dcas_x86_64< Signed > >
174 {
175 };
176 
177 #else
178 
179 template< bool Signed >
180 struct operations< 16u, Signed > :
181     public gcc_atomic_operations< typename make_storage_type< 16u, Signed >::type >
182 {
183     typedef typename make_storage_type< 16u, Signed >::aligned aligned_storage_type;
184 };
185 
186 #endif
187 #endif
188 
189 
190 #if BOOST_ATOMIC_INT64_LOCK_FREE > 0
191 #if defined(__clang__) && defined(BOOST_ATOMIC_DETAIL_X86_HAS_CMPXCHG8B)
192 
193 // Workaround for clang bug http://llvm.org/bugs/show_bug.cgi?id=19355
194 template< bool Signed >
195 struct operations< 8u, Signed > :
196     public cas_based_operations< gcc_dcas_x86< Signed > >
197 {
198 };
199 
200 #elif (BOOST_ATOMIC_DETAIL_SIZEOF_LLONG == 8 && __GCC_ATOMIC_LLONG_LOCK_FREE != BOOST_ATOMIC_LLONG_LOCK_FREE) ||\
201     (BOOST_ATOMIC_DETAIL_SIZEOF_LONG == 8 && __GCC_ATOMIC_LONG_LOCK_FREE != BOOST_ATOMIC_LONG_LOCK_FREE) ||\
202     (BOOST_ATOMIC_DETAIL_SIZEOF_INT == 8 && __GCC_ATOMIC_INT_LOCK_FREE != BOOST_ATOMIC_INT_LOCK_FREE) ||\
203     (BOOST_ATOMIC_DETAIL_SIZEOF_SHORT == 8 && __GCC_ATOMIC_SHORT_LOCK_FREE != BOOST_ATOMIC_SHORT_LOCK_FREE) ||\
204     (BOOST_ATOMIC_DETAIL_SIZEOF_WCHAR_T == 8 && __GCC_ATOMIC_WCHAR_T_LOCK_FREE != BOOST_ATOMIC_WCHAR_T_LOCK_FREE)
205 
206 #define BOOST_ATOMIC_DETAIL_INT64_EXTENDED
207 
208 template< bool Signed >
209 struct operations< 8u, Signed > :
210     public extending_cas_based_operations< gcc_atomic_operations< typename make_storage_type< 16u, Signed >::type >, 8u, Signed >
211 {
212     typedef typename make_storage_type< 16u, Signed >::aligned aligned_storage_type;
213 };
214 
215 #else
216 
217 template< bool Signed >
218 struct operations< 8u, Signed > :
219     public gcc_atomic_operations< typename make_storage_type< 8u, Signed >::type >
220 {
221     typedef typename make_storage_type< 8u, Signed >::aligned aligned_storage_type;
222 };
223 
224 #endif
225 #endif
226 
227 #if BOOST_ATOMIC_INT32_LOCK_FREE > 0
228 #if (BOOST_ATOMIC_DETAIL_SIZEOF_LLONG == 4 && __GCC_ATOMIC_LLONG_LOCK_FREE != BOOST_ATOMIC_LLONG_LOCK_FREE) ||\
229     (BOOST_ATOMIC_DETAIL_SIZEOF_LONG == 4 && __GCC_ATOMIC_LONG_LOCK_FREE != BOOST_ATOMIC_LONG_LOCK_FREE) ||\
230     (BOOST_ATOMIC_DETAIL_SIZEOF_INT == 4 && __GCC_ATOMIC_INT_LOCK_FREE != BOOST_ATOMIC_INT_LOCK_FREE) ||\
231     (BOOST_ATOMIC_DETAIL_SIZEOF_SHORT == 4 && __GCC_ATOMIC_SHORT_LOCK_FREE != BOOST_ATOMIC_SHORT_LOCK_FREE) ||\
232     (BOOST_ATOMIC_DETAIL_SIZEOF_WCHAR_T == 4 && __GCC_ATOMIC_WCHAR_T_LOCK_FREE != BOOST_ATOMIC_WCHAR_T_LOCK_FREE)
233 
234 #define BOOST_ATOMIC_DETAIL_INT32_EXTENDED
235 
236 #if !defined(BOOST_ATOMIC_DETAIL_INT64_EXTENDED)
237 
238 template< bool Signed >
239 struct operations< 4u, Signed > :
240     public extending_cas_based_operations< gcc_atomic_operations< typename make_storage_type< 8u, Signed >::type >, 4u, Signed >
241 {
242     typedef typename make_storage_type< 8u, Signed >::aligned aligned_storage_type;
243 };
244 
245 #else // !defined(BOOST_ATOMIC_DETAIL_INT64_EXTENDED)
246 
247 template< bool Signed >
248 struct operations< 4u, Signed > :
249     public extending_cas_based_operations< gcc_atomic_operations< typename make_storage_type< 16u, Signed >::type >, 4u, Signed >
250 {
251     typedef typename make_storage_type< 16u, Signed >::aligned aligned_storage_type;
252 };
253 
254 #endif // !defined(BOOST_ATOMIC_DETAIL_INT64_EXTENDED)
255 
256 #else
257 
258 template< bool Signed >
259 struct operations< 4u, Signed > :
260     public gcc_atomic_operations< typename make_storage_type< 4u, Signed >::type >
261 {
262     typedef typename make_storage_type< 4u, Signed >::aligned aligned_storage_type;
263 };
264 
265 #endif
266 #endif
267 
268 #if BOOST_ATOMIC_INT16_LOCK_FREE > 0
269 #if (BOOST_ATOMIC_DETAIL_SIZEOF_LLONG == 2 && __GCC_ATOMIC_LLONG_LOCK_FREE != BOOST_ATOMIC_LLONG_LOCK_FREE) ||\
270     (BOOST_ATOMIC_DETAIL_SIZEOF_LONG == 2 && __GCC_ATOMIC_LONG_LOCK_FREE != BOOST_ATOMIC_LONG_LOCK_FREE) ||\
271     (BOOST_ATOMIC_DETAIL_SIZEOF_INT == 2 && __GCC_ATOMIC_INT_LOCK_FREE != BOOST_ATOMIC_INT_LOCK_FREE) ||\
272     (BOOST_ATOMIC_DETAIL_SIZEOF_SHORT == 2 && __GCC_ATOMIC_SHORT_LOCK_FREE != BOOST_ATOMIC_SHORT_LOCK_FREE) ||\
273     (BOOST_ATOMIC_DETAIL_SIZEOF_WCHAR_T == 2 && __GCC_ATOMIC_WCHAR_T_LOCK_FREE != BOOST_ATOMIC_WCHAR_T_LOCK_FREE)
274 
275 #define BOOST_ATOMIC_DETAIL_INT16_EXTENDED
276 
277 #if !defined(BOOST_ATOMIC_DETAIL_INT32_EXTENDED)
278 
279 template< bool Signed >
280 struct operations< 2u, Signed > :
281     public extending_cas_based_operations< gcc_atomic_operations< typename make_storage_type< 4u, Signed >::type >, 2u, Signed >
282 {
283     typedef typename make_storage_type< 4u, Signed >::aligned aligned_storage_type;
284 };
285 
286 #elif !defined(BOOST_ATOMIC_DETAIL_INT64_EXTENDED)
287 
288 template< bool Signed >
289 struct operations< 2u, Signed > :
290     public extending_cas_based_operations< gcc_atomic_operations< typename make_storage_type< 8u, Signed >::type >, 2u, Signed >
291 {
292     typedef typename make_storage_type< 8u, Signed >::aligned aligned_storage_type;
293 };
294 
295 #else
296 
297 template< bool Signed >
298 struct operations< 2u, Signed > :
299     public extending_cas_based_operations< gcc_atomic_operations< typename make_storage_type< 16u, Signed >::type >, 2u, Signed >
300 {
301     typedef typename make_storage_type< 16u, Signed >::aligned aligned_storage_type;
302 };
303 
304 #endif
305 
306 #else
307 
308 template< bool Signed >
309 struct operations< 2u, Signed > :
310     public gcc_atomic_operations< typename make_storage_type< 2u, Signed >::type >
311 {
312     typedef typename make_storage_type< 2u, Signed >::aligned aligned_storage_type;
313 };
314 
315 #endif
316 #endif
317 
318 #if BOOST_ATOMIC_INT8_LOCK_FREE > 0
319 #if (BOOST_ATOMIC_DETAIL_SIZEOF_LLONG == 1 && __GCC_ATOMIC_LLONG_LOCK_FREE != BOOST_ATOMIC_LLONG_LOCK_FREE) ||\
320     (BOOST_ATOMIC_DETAIL_SIZEOF_LONG == 1 && __GCC_ATOMIC_LONG_LOCK_FREE != BOOST_ATOMIC_LONG_LOCK_FREE) ||\
321     (BOOST_ATOMIC_DETAIL_SIZEOF_INT == 1 && __GCC_ATOMIC_INT_LOCK_FREE != BOOST_ATOMIC_INT_LOCK_FREE) ||\
322     (BOOST_ATOMIC_DETAIL_SIZEOF_SHORT == 1 && __GCC_ATOMIC_SHORT_LOCK_FREE != BOOST_ATOMIC_SHORT_LOCK_FREE) ||\
323     (BOOST_ATOMIC_DETAIL_SIZEOF_WCHAR_T == 1 && __GCC_ATOMIC_WCHAR_T_LOCK_FREE != BOOST_ATOMIC_WCHAR_T_LOCK_FREE) ||\
324     (__GCC_ATOMIC_CHAR_LOCK_FREE != BOOST_ATOMIC_CHAR_LOCK_FREE) ||\
325     (__GCC_ATOMIC_BOOL_LOCK_FREE != BOOST_ATOMIC_BOOL_LOCK_FREE)
326 
327 #if !defined(BOOST_ATOMIC_DETAIL_INT16_EXTENDED)
328 
329 template< bool Signed >
330 struct operations< 1u, Signed > :
331     public extending_cas_based_operations< gcc_atomic_operations< typename make_storage_type< 2u, Signed >::type >, 1u, Signed >
332 {
333     typedef typename make_storage_type< 2u, Signed >::aligned aligned_storage_type;
334 };
335 
336 #elif !defined(BOOST_ATOMIC_DETAIL_INT32_EXTENDED)
337 
338 template< bool Signed >
339 struct operations< 1u, Signed > :
340     public extending_cas_based_operations< gcc_atomic_operations< typename make_storage_type< 4u, Signed >::type >, 1u, Signed >
341 {
342     typedef typename make_storage_type< 4u, Signed >::aligned aligned_storage_type;
343 };
344 
345 #elif !defined(BOOST_ATOMIC_DETAIL_INT64_EXTENDED)
346 
347 template< bool Signed >
348 struct operations< 1u, Signed > :
349     public extending_cas_based_operations< gcc_atomic_operations< typename make_storage_type< 8u, Signed >::type >, 1u, Signed >
350 {
351     typedef typename make_storage_type< 8u, Signed >::aligned aligned_storage_type;
352 };
353 
354 #else
355 
356 template< bool Signed >
357 struct operations< 1u, Signed > :
358     public extending_cas_based_operations< gcc_atomic_operations< typename make_storage_type< 16u, Signed >::type >, 1u, Signed >
359 {
360     typedef typename make_storage_type< 16u, Signed >::aligned aligned_storage_type;
361 };
362 
363 #endif
364 
365 #else
366 
367 template< bool Signed >
368 struct operations< 1u, Signed > :
369     public gcc_atomic_operations< typename make_storage_type< 1u, Signed >::type >
370 {
371     typedef typename make_storage_type< 1u, Signed >::aligned aligned_storage_type;
372 };
373 
374 #endif
375 #endif
376 
377 #undef BOOST_ATOMIC_DETAIL_INT16_EXTENDED
378 #undef BOOST_ATOMIC_DETAIL_INT32_EXTENDED
379 #undef BOOST_ATOMIC_DETAIL_INT64_EXTENDED
380 
thread_fence(memory_order order)381 BOOST_FORCEINLINE void thread_fence(memory_order order) BOOST_NOEXCEPT
382 {
383     __atomic_thread_fence(atomics::detail::convert_memory_order_to_gcc(order));
384 }
385 
signal_fence(memory_order order)386 BOOST_FORCEINLINE void signal_fence(memory_order order) BOOST_NOEXCEPT
387 {
388     __atomic_signal_fence(atomics::detail::convert_memory_order_to_gcc(order));
389 }
390 
391 } // namespace detail
392 } // namespace atomics
393 } // namespace boost
394 
395 #endif // BOOST_ATOMIC_DETAIL_OPS_GCC_ATOMIC_HPP_INCLUDED_
396