1 | // (C) Copyright John Maddock 2000. |
---|
2 | // Use, modification and distribution are subject to the Boost Software License, |
---|
3 | // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
---|
4 | // http://www.boost.org/LICENSE_1_0.txt). |
---|
5 | // |
---|
6 | // See http://www.boost.org/libs/type_traits for most recent version including documentation. |
---|
7 | |
---|
8 | #ifndef BOOST_TT_TYPE_WITH_ALIGNMENT_INCLUDED |
---|
9 | #define BOOST_TT_TYPE_WITH_ALIGNMENT_INCLUDED |
---|
10 | |
---|
11 | #include <boost/mpl/if.hpp> |
---|
12 | #include <boost/preprocessor/list/for_each_i.hpp> |
---|
13 | #include <boost/preprocessor/tuple/to_list.hpp> |
---|
14 | #include <boost/preprocessor/cat.hpp> |
---|
15 | #include <boost/preprocessor/list/transform.hpp> |
---|
16 | #include <boost/preprocessor/list/append.hpp> |
---|
17 | #include <boost/type_traits/alignment_of.hpp> |
---|
18 | #include <boost/type_traits/is_pod.hpp> |
---|
19 | #include <boost/static_assert.hpp> |
---|
20 | #include <boost/config.hpp> |
---|
21 | |
---|
22 | // should be the last #include |
---|
23 | #include <boost/type_traits/detail/bool_trait_def.hpp> |
---|
24 | |
---|
25 | #include <cstddef> |
---|
26 | |
---|
27 | #ifdef BOOST_MSVC |
---|
28 | # pragma warning(push) |
---|
29 | # pragma warning(disable: 4121) // alignment is sensitive to packing |
---|
30 | #endif |
---|
31 | |
---|
32 | namespace boost { |
---|
33 | |
---|
34 | #ifndef __BORLANDC__ |
---|
35 | |
---|
36 | namespace detail { |
---|
37 | |
---|
38 | class alignment_dummy; |
---|
39 | typedef void (*function_ptr)(); |
---|
40 | typedef int (alignment_dummy::*member_ptr); |
---|
41 | typedef int (alignment_dummy::*member_function_ptr)(); |
---|
42 | |
---|
43 | #ifdef BOOST_HAS_LONG_LONG |
---|
44 | #define BOOST_TT_ALIGNMENT_BASE_TYPES BOOST_PP_TUPLE_TO_LIST( \ |
---|
45 | 12, ( \ |
---|
46 | char, short, int, long, ::boost::long_long_type, float, double, long double \ |
---|
47 | , void*, function_ptr, member_ptr, member_function_ptr)) |
---|
48 | #else |
---|
49 | #define BOOST_TT_ALIGNMENT_BASE_TYPES BOOST_PP_TUPLE_TO_LIST( \ |
---|
50 | 11, ( \ |
---|
51 | char, short, int, long, float, double, long double \ |
---|
52 | , void*, function_ptr, member_ptr, member_function_ptr)) |
---|
53 | #endif |
---|
54 | |
---|
55 | #define BOOST_TT_HAS_ONE_T(D,Data,T) boost::detail::has_one_T< T > |
---|
56 | |
---|
57 | #define BOOST_TT_ALIGNMENT_STRUCT_TYPES \ |
---|
58 | BOOST_PP_LIST_TRANSFORM(BOOST_TT_HAS_ONE_T, \ |
---|
59 | X, \ |
---|
60 | BOOST_TT_ALIGNMENT_BASE_TYPES) |
---|
61 | |
---|
62 | #define BOOST_TT_ALIGNMENT_TYPES \ |
---|
63 | BOOST_PP_LIST_APPEND(BOOST_TT_ALIGNMENT_BASE_TYPES, \ |
---|
64 | BOOST_TT_ALIGNMENT_STRUCT_TYPES) |
---|
65 | |
---|
66 | // |
---|
67 | // lower_alignment_helper -- |
---|
68 | // |
---|
69 | // This template gets instantiated a lot, so use partial |
---|
70 | // specialization when available to reduce the compiler burden. |
---|
71 | // |
---|
72 | #ifdef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION |
---|
73 | template <bool found = true> |
---|
74 | struct lower_alignment_helper_impl |
---|
75 | { |
---|
76 | template <std::size_t, class> |
---|
77 | struct apply |
---|
78 | { |
---|
79 | typedef char type; |
---|
80 | enum { value = true }; |
---|
81 | }; |
---|
82 | }; |
---|
83 | |
---|
84 | template <> |
---|
85 | struct lower_alignment_helper_impl<false> |
---|
86 | { |
---|
87 | template <std::size_t target, class TestType> |
---|
88 | struct apply |
---|
89 | : mpl::if_c<(alignment_of<TestType>::value == target), TestType, char> |
---|
90 | { |
---|
91 | enum { value = (alignment_of<TestType>::value == target) }; |
---|
92 | }; |
---|
93 | }; |
---|
94 | |
---|
95 | template <bool found, std::size_t target, class TestType> |
---|
96 | struct lower_alignment_helper |
---|
97 | : lower_alignment_helper_impl<found>::template apply<target,TestType> |
---|
98 | { |
---|
99 | }; |
---|
100 | #else |
---|
101 | template <bool found, std::size_t target, class TestType> |
---|
102 | struct lower_alignment_helper |
---|
103 | { |
---|
104 | typedef char type; |
---|
105 | enum { value = true }; |
---|
106 | }; |
---|
107 | |
---|
108 | template <std::size_t target, class TestType> |
---|
109 | struct lower_alignment_helper<false,target,TestType> |
---|
110 | { |
---|
111 | enum { value = (alignment_of<TestType>::value == target) }; |
---|
112 | typedef typename mpl::if_c<value, TestType, char>::type type; |
---|
113 | }; |
---|
114 | #endif |
---|
115 | |
---|
116 | #define BOOST_TT_CHOOSE_MIN_ALIGNMENT(R,P,I,T) \ |
---|
117 | typename lower_alignment_helper< \ |
---|
118 | BOOST_PP_CAT(found,I),target,T \ |
---|
119 | >::type BOOST_PP_CAT(t,I); \ |
---|
120 | enum { \ |
---|
121 | BOOST_PP_CAT(found,BOOST_PP_INC(I)) \ |
---|
122 | = lower_alignment_helper<BOOST_PP_CAT(found,I),target,T >::value \ |
---|
123 | }; |
---|
124 | |
---|
125 | #define BOOST_TT_CHOOSE_T(R,P,I,T) T BOOST_PP_CAT(t,I); |
---|
126 | |
---|
127 | template <typename T> |
---|
128 | struct has_one_T |
---|
129 | { |
---|
130 | T data; |
---|
131 | }; |
---|
132 | |
---|
133 | template <std::size_t target> |
---|
134 | union lower_alignment |
---|
135 | { |
---|
136 | enum { found0 = false }; |
---|
137 | |
---|
138 | BOOST_PP_LIST_FOR_EACH_I( |
---|
139 | BOOST_TT_CHOOSE_MIN_ALIGNMENT |
---|
140 | , ignored |
---|
141 | , BOOST_TT_ALIGNMENT_TYPES |
---|
142 | ) |
---|
143 | }; |
---|
144 | |
---|
145 | union max_align |
---|
146 | { |
---|
147 | BOOST_PP_LIST_FOR_EACH_I( |
---|
148 | BOOST_TT_CHOOSE_T |
---|
149 | , ignored |
---|
150 | , BOOST_TT_ALIGNMENT_TYPES |
---|
151 | ) |
---|
152 | }; |
---|
153 | |
---|
154 | #undef BOOST_TT_ALIGNMENT_BASE_TYPES |
---|
155 | #undef BOOST_TT_HAS_ONE_T |
---|
156 | #undef BOOST_TT_ALIGNMENT_STRUCT_TYPES |
---|
157 | #undef BOOST_TT_ALIGNMENT_TYPES |
---|
158 | #undef BOOST_TT_CHOOSE_MIN_ALIGNMENT |
---|
159 | #undef BOOST_TT_CHOOSE_T |
---|
160 | |
---|
161 | template<std::size_t TAlign, std::size_t Align> |
---|
162 | struct is_aligned |
---|
163 | { |
---|
164 | BOOST_STATIC_CONSTANT(bool, |
---|
165 | value = (TAlign >= Align) & (TAlign % Align == 0) |
---|
166 | ); |
---|
167 | }; |
---|
168 | |
---|
169 | #ifdef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION |
---|
170 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::detail::max_align,true) |
---|
171 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::detail::lower_alignment<1> ,true) |
---|
172 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::detail::lower_alignment<2> ,true) |
---|
173 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::detail::lower_alignment<4> ,true) |
---|
174 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::detail::lower_alignment<8> ,true) |
---|
175 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::detail::lower_alignment<10> ,true) |
---|
176 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::detail::lower_alignment<16> ,true) |
---|
177 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::detail::lower_alignment<32> ,true) |
---|
178 | #endif |
---|
179 | |
---|
180 | } // namespace detail |
---|
181 | |
---|
182 | #ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION |
---|
183 | template<std::size_t Align> |
---|
184 | struct is_pod< ::boost::detail::lower_alignment<Align> > |
---|
185 | { |
---|
186 | BOOST_STATIC_CONSTANT(std::size_t, value = true); |
---|
187 | }; |
---|
188 | #endif |
---|
189 | |
---|
190 | // This alignment method originally due to Brian Parker, implemented by David |
---|
191 | // Abrahams, and then ported here by Doug Gregor. |
---|
192 | namespace detail{ |
---|
193 | |
---|
194 | template <std::size_t Align> |
---|
195 | class type_with_alignment_imp |
---|
196 | { |
---|
197 | typedef ::boost::detail::lower_alignment<Align> t1; |
---|
198 | typedef typename mpl::if_c< |
---|
199 | ::boost::detail::is_aligned< ::boost::alignment_of<t1>::value,Align >::value |
---|
200 | , t1 |
---|
201 | , ::boost::detail::max_align |
---|
202 | >::type align_t; |
---|
203 | |
---|
204 | BOOST_STATIC_CONSTANT(std::size_t, found = alignment_of<align_t>::value); |
---|
205 | |
---|
206 | BOOST_STATIC_ASSERT(found >= Align); |
---|
207 | BOOST_STATIC_ASSERT(found % Align == 0); |
---|
208 | |
---|
209 | public: |
---|
210 | typedef align_t type; |
---|
211 | }; |
---|
212 | |
---|
213 | } |
---|
214 | |
---|
215 | template <std::size_t Align> |
---|
216 | class type_with_alignment |
---|
217 | : public ::boost::detail::type_with_alignment_imp<Align> |
---|
218 | { |
---|
219 | }; |
---|
220 | |
---|
221 | #if defined(__GNUC__) |
---|
222 | namespace align { |
---|
223 | struct __attribute__((__aligned__(2))) a2 {}; |
---|
224 | struct __attribute__((__aligned__(4))) a4 {}; |
---|
225 | struct __attribute__((__aligned__(8))) a8 {}; |
---|
226 | struct __attribute__((__aligned__(16))) a16 {}; |
---|
227 | struct __attribute__((__aligned__(32))) a32 {}; |
---|
228 | } |
---|
229 | |
---|
230 | template<> class type_with_alignment<1> { public: typedef char type; }; |
---|
231 | template<> class type_with_alignment<2> { public: typedef align::a2 type; }; |
---|
232 | template<> class type_with_alignment<4> { public: typedef align::a4 type; }; |
---|
233 | template<> class type_with_alignment<8> { public: typedef align::a8 type; }; |
---|
234 | template<> class type_with_alignment<16> { public: typedef align::a16 type; }; |
---|
235 | template<> class type_with_alignment<32> { public: typedef align::a32 type; }; |
---|
236 | |
---|
237 | namespace detail { |
---|
238 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::align::a2,true) |
---|
239 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::align::a4,true) |
---|
240 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::align::a8,true) |
---|
241 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::align::a16,true) |
---|
242 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::align::a32,true) |
---|
243 | } |
---|
244 | #endif |
---|
245 | #if (defined(BOOST_MSVC) || (defined(BOOST_INTEL) && defined(_MSC_VER))) && _MSC_VER >= 1300 |
---|
246 | // |
---|
247 | // MSVC supports types which have alignments greater than the normal |
---|
248 | // maximum: these are used for example in the types __m64 and __m128 |
---|
249 | // to provide types with alignment requirements which match the SSE |
---|
250 | // registers. Therefore we extend type_with_alignment<> to support |
---|
251 | // such types, however, we have to be careful to use a builtin type |
---|
252 | // whenever possible otherwise we break previously working code: |
---|
253 | // see http://article.gmane.org/gmane.comp.lib.boost.devel/173011 |
---|
254 | // for an example and test case. Thus types like a8 below will |
---|
255 | // be used *only* if the existing implementation can't provide a type |
---|
256 | // with suitable alignment. This does mean however, that type_with_alignment<> |
---|
257 | // may return a type which cannot be passed through a function call |
---|
258 | // by value (and neither can any type containing such a type like |
---|
259 | // Boost.Optional). However, this only happens when we have no choice |
---|
260 | // in the matter because no other "ordinary" type is available. |
---|
261 | // |
---|
262 | namespace align { |
---|
263 | struct __declspec(align(8)) a8 { |
---|
264 | char m[8]; |
---|
265 | typedef a8 type; |
---|
266 | }; |
---|
267 | struct __declspec(align(16)) a16 { |
---|
268 | char m[16]; |
---|
269 | typedef a16 type; |
---|
270 | }; |
---|
271 | struct __declspec(align(32)) a32 { |
---|
272 | char m[32]; |
---|
273 | typedef a32 type; |
---|
274 | }; |
---|
275 | struct __declspec(align(64)) a64 |
---|
276 | { |
---|
277 | char m[64]; |
---|
278 | typedef a64 type; |
---|
279 | }; |
---|
280 | struct __declspec(align(128)) a128 { |
---|
281 | char m[128]; |
---|
282 | typedef a128 type; |
---|
283 | }; |
---|
284 | } |
---|
285 | |
---|
286 | template<> class type_with_alignment<8> |
---|
287 | { |
---|
288 | typedef mpl::if_c< |
---|
289 | ::boost::alignment_of<boost::detail::max_align>::value < 8, |
---|
290 | align::a8, |
---|
291 | boost::detail::type_with_alignment_imp<8> >::type t1; |
---|
292 | public: |
---|
293 | typedef t1::type type; |
---|
294 | }; |
---|
295 | template<> class type_with_alignment<16> |
---|
296 | { |
---|
297 | typedef mpl::if_c< |
---|
298 | ::boost::alignment_of<boost::detail::max_align>::value < 16, |
---|
299 | align::a16, |
---|
300 | boost::detail::type_with_alignment_imp<16> >::type t1; |
---|
301 | public: |
---|
302 | typedef t1::type type; |
---|
303 | }; |
---|
304 | template<> class type_with_alignment<32> |
---|
305 | { |
---|
306 | typedef mpl::if_c< |
---|
307 | ::boost::alignment_of<boost::detail::max_align>::value < 32, |
---|
308 | align::a32, |
---|
309 | boost::detail::type_with_alignment_imp<32> >::type t1; |
---|
310 | public: |
---|
311 | typedef t1::type type; |
---|
312 | }; |
---|
313 | template<> class type_with_alignment<64> { |
---|
314 | typedef mpl::if_c< |
---|
315 | ::boost::alignment_of<boost::detail::max_align>::value < 64, |
---|
316 | align::a64, |
---|
317 | boost::detail::type_with_alignment_imp<64> >::type t1; |
---|
318 | public: |
---|
319 | typedef t1::type type; |
---|
320 | }; |
---|
321 | template<> class type_with_alignment<128> { |
---|
322 | typedef mpl::if_c< |
---|
323 | ::boost::alignment_of<boost::detail::max_align>::value < 128, |
---|
324 | align::a128, |
---|
325 | boost::detail::type_with_alignment_imp<128> >::type t1; |
---|
326 | public: |
---|
327 | typedef t1::type type; |
---|
328 | }; |
---|
329 | |
---|
330 | namespace detail { |
---|
331 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::align::a8,true) |
---|
332 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::align::a16,true) |
---|
333 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::align::a32,true) |
---|
334 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::align::a64,true) |
---|
335 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::align::a128,true) |
---|
336 | } |
---|
337 | #endif |
---|
338 | |
---|
339 | #else |
---|
340 | |
---|
341 | // |
---|
342 | // Borland specific version, we have this for two reasons: |
---|
343 | // 1) The version above doesn't always compile (with the new test cases for example) |
---|
344 | // 2) Because of Borlands #pragma option we can create types with alignments that are |
---|
345 | // greater that the largest aligned builtin type. |
---|
346 | |
---|
347 | namespace align{ |
---|
348 | #pragma option push -a16 |
---|
349 | struct a2{ short s; }; |
---|
350 | struct a4{ int s; }; |
---|
351 | struct a8{ double s; }; |
---|
352 | struct a16{ long double s; }; |
---|
353 | #pragma option pop |
---|
354 | } |
---|
355 | |
---|
356 | namespace detail { |
---|
357 | |
---|
358 | typedef ::boost::align::a16 max_align; |
---|
359 | |
---|
360 | //#if ! BOOST_WORKAROUND(__CODEGEARC__, BOOST_TESTED_AT(0x610)) |
---|
361 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::align::a2,true) |
---|
362 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::align::a4,true) |
---|
363 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::align::a8,true) |
---|
364 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pod,::boost::align::a16,true) |
---|
365 | //#endif |
---|
366 | } |
---|
367 | |
---|
368 | template <std::size_t N> struct type_with_alignment |
---|
369 | { |
---|
370 | // We should never get to here, but if we do use the maximally |
---|
371 | // aligned type: |
---|
372 | // BOOST_STATIC_ASSERT(0); |
---|
373 | typedef align::a16 type; |
---|
374 | }; |
---|
375 | template <> struct type_with_alignment<1>{ typedef char type; }; |
---|
376 | template <> struct type_with_alignment<2>{ typedef align::a2 type; }; |
---|
377 | template <> struct type_with_alignment<4>{ typedef align::a4 type; }; |
---|
378 | template <> struct type_with_alignment<8>{ typedef align::a8 type; }; |
---|
379 | template <> struct type_with_alignment<16>{ typedef align::a16 type; }; |
---|
380 | |
---|
381 | #endif |
---|
382 | |
---|
383 | } // namespace boost |
---|
384 | |
---|
385 | #ifdef BOOST_MSVC |
---|
386 | # pragma warning(pop) |
---|
387 | #endif |
---|
388 | |
---|
389 | #include <boost/type_traits/detail/bool_trait_undef.hpp> |
---|
390 | |
---|
391 | #endif // BOOST_TT_TYPE_WITH_ALIGNMENT_INCLUDED |
---|
392 | |
---|
393 | |
---|