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1 //----------------------------------------------------------------------------- |
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2 // boost aligned_storage.hpp header file |
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3 // See http://www.boost.org for updates, documentation, and revision history. |
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4 //----------------------------------------------------------------------------- |
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5 // |
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6 // Copyright (c) 2002-2003 |
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7 // Eric Friedman, Itay Maman |
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8 // |
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9 // Distributed under the Boost Software License, Version 1.0. (See |
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10 // accompanying file LICENSE_1_0.txt or copy at |
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11 // http://www.boost.org/LICENSE_1_0.txt) |
1 |
12 |
2 // Copyright (C) John Maddock 2005. |
13 #ifndef BOOST_ALIGNED_STORAGE_HPP |
3 // Use, modification and distribution are subject to the Boost Software License, |
14 #define BOOST_ALIGNED_STORAGE_HPP |
4 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
15 |
5 // http://www.boost.org/LICENSE_1_0.txt). |
16 #include <cstddef> // for std::size_t |
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17 |
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18 #include "boost/config.hpp" |
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19 #include "boost/detail/workaround.hpp" |
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20 #include "boost/type_traits/alignment_of.hpp" |
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21 #include "boost/type_traits/type_with_alignment.hpp" |
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22 #include "boost/type_traits/is_pod.hpp" |
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23 |
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24 #include "boost/mpl/eval_if.hpp" |
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25 #include "boost/mpl/identity.hpp" |
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26 |
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27 #include "boost/type_traits/detail/bool_trait_def.hpp" |
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28 |
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29 namespace boost { |
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30 |
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31 namespace detail { namespace aligned_storage { |
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32 |
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33 BOOST_STATIC_CONSTANT( |
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34 std::size_t |
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35 , alignment_of_max_align = ::boost::alignment_of<max_align>::value |
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36 ); |
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37 |
6 // |
38 // |
7 // See http://www.boost.org/libs/type_traits for most recent version including documentation. |
39 // To be TR1 conforming this must be a POD type: |
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40 // |
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41 template < |
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42 std::size_t size_ |
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43 , std::size_t alignment_ |
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44 > |
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45 struct aligned_storage_imp |
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46 { |
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47 union data_t |
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48 { |
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49 char buf[size_]; |
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50 |
9 #ifndef BOOST_TT_ALIGNED_STORAGE_HPP_INCLUDED |
51 typename mpl::eval_if_c< |
10 # define BOOST_TT_ALIGNED_STORAGE_HPP_INCLUDED |
52 alignment_ == std::size_t(-1) |
11 # include <boost/aligned_storage.hpp> |
53 , mpl::identity<detail::max_align> |
12 #endif // BOOST_TT_ALIGNED_STORAGE_HPP_INCLUDED |
54 , type_with_alignment<alignment_> |
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55 >::type align_; |
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56 } data_; |
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57 }; |
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58 |
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59 }} // namespace detail::aligned_storage |
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60 |
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61 template < |
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62 std::size_t size_ |
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63 , std::size_t alignment_ = std::size_t(-1) |
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64 > |
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65 class aligned_storage |
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66 { |
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67 private: // representation |
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68 |
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69 detail::aligned_storage::aligned_storage_imp<size_, alignment_> data_; |
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70 |
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71 public: // constants |
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72 |
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73 typedef detail::aligned_storage::aligned_storage_imp<size_, alignment_> type; |
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74 |
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75 BOOST_STATIC_CONSTANT( |
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76 std::size_t |
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77 , size = size_ |
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78 ); |
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79 BOOST_STATIC_CONSTANT( |
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80 std::size_t |
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81 , alignment = ( |
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82 alignment_ == std::size_t(-1) |
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83 ? ::boost::detail::aligned_storage::alignment_of_max_align |
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84 : alignment_ |
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85 ) |
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86 ); |
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87 |
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88 #if defined(__GNUC__) &&\ |
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89 (__GNUC__ > 3) ||\ |
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90 (__GNUC__ == 3 && (__GNUC_MINOR__ > 2 ||\ |
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91 (__GNUC_MINOR__ == 2 && __GNUC_PATCHLEVEL__ >=3))) |
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92 |
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93 private: // noncopyable |
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94 |
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95 aligned_storage(const aligned_storage&); |
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96 aligned_storage& operator=(const aligned_storage&); |
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97 |
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98 #else // gcc less than 3.2.3 |
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99 |
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100 public: // _should_ be noncopyable, but GCC compiler emits error |
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101 |
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102 aligned_storage(const aligned_storage&); |
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103 aligned_storage& operator=(const aligned_storage&); |
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104 |
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105 #endif // gcc < 3.2.3 workaround |
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106 |
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107 public: // structors |
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108 |
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109 aligned_storage() |
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110 { |
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111 } |
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112 |
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113 ~aligned_storage() |
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114 { |
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115 } |
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116 |
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117 public: // accessors |
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118 |
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119 void* address() |
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120 { |
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121 return this; |
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122 } |
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123 |
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124 #if !BOOST_WORKAROUND(BOOST_MSVC, < 1300) |
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125 |
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126 const void* address() const |
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127 { |
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128 return this; |
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129 } |
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130 |
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131 #else // MSVC6 |
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132 |
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133 const void* address() const; |
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134 |
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135 #endif // MSVC6 workaround |
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136 |
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137 }; |
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138 |
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139 #if BOOST_WORKAROUND(BOOST_MSVC, < 1300) |
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140 |
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141 // MSVC6 seems not to like inline functions with const void* returns, so we |
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142 // declare the following here: |
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143 |
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144 template <std::size_t S, std::size_t A> |
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145 const void* aligned_storage<S,A>::address() const |
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146 { |
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147 return const_cast< aligned_storage<S,A>* >(this)->address(); |
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148 } |
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149 |
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150 #endif // MSVC6 workaround |
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151 |
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152 #ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION |
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153 // |
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154 // Make sure that is_pod recognises aligned_storage<>::type |
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155 // as a POD (Note that aligned_storage<> itself is not a POD): |
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156 // |
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157 template <std::size_t size_, std::size_t alignment_> |
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158 struct is_pod<boost::detail::aligned_storage::aligned_storage_imp<size_,alignment_> > |
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159 BOOST_TT_AUX_BOOL_C_BASE(true) |
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160 { |
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161 BOOST_TT_AUX_BOOL_TRAIT_VALUE_DECL(true) |
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162 }; |
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163 #endif |
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164 |
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165 |
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166 } // namespace boost |
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167 |
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168 #include "boost/type_traits/detail/bool_trait_undef.hpp" |
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169 |
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170 #endif // BOOST_ALIGNED_STORAGE_HPP |