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The C and C++ Include Header Files
cat -n /usr/include/c++/15/bits/mask_array.h
1 // The template and inlines for the -*- C++ -*- mask_array class. 2 3 // Copyright (C) 1997-2025 Free Software Foundation, Inc. 4 // 5 // This file is part of the GNU ISO C++ Library. This library is free 6 // software; you can redistribute it and/or modify it under the 7 // terms of the GNU General Public License as published by the 8 // Free Software Foundation; either version 3, or (at your option) 9 // any later version. 10 11 // This library is distributed in the hope that it will be useful, 12 // but WITHOUT ANY WARRANTY; without even the implied warranty of 13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 // GNU General Public License for more details. 15 16 // Under Section 7 of GPL version 3, you are granted additional 17 // permissions described in the GCC Runtime Library Exception, version 18 // 3.1, as published by the Free Software Foundation. 19 20 // You should have received a copy of the GNU General Public License and 21 // a copy of the GCC Runtime Library Exception along with this program; 22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 // <http://www.gnu.org/licenses/>. 24 25 /** @file bits/mask_array.h 26 * This is an internal header file, included by other library headers. 27 * Do not attempt to use it directly. @headername{valarray} 28 */ 29 30 // Written by Gabriel Dos Reis <Gabriel.Dos-Reis@DPTMaths.ENS-Cachan.Fr> 31 32 #ifndef _MASK_ARRAY_H 33 #define _MASK_ARRAY_H 1 34 35 #ifdef _GLIBCXX_SYSHDR 36 #pragma GCC system_header 37 #endif 38 39 namespace std _GLIBCXX_VISIBILITY(default) 40 { 41 _GLIBCXX_BEGIN_NAMESPACE_VERSION 42 43 /** 44 * @addtogroup numeric_arrays 45 * @{ 46 */ 47 48 /** 49 * @brief Reference to selected subset of an array. 50 * 51 * A mask_array is a reference to the actual elements of an array specified 52 * by a bitmask in the form of an array of bool. The way to get a 53 * mask_array is to call operator[](valarray<bool>) on a valarray. The 54 * returned mask_array then permits carrying operations out on the 55 * referenced subset of elements in the original valarray. 56 * 57 * For example, if a mask_array is obtained using the array (false, true, 58 * false, true) as an argument, the mask array has two elements referring 59 * to array[1] and array[3] in the underlying array. 60 * 61 * @param Tp Element type. 62 */ 63 template <class _Tp> 64 class mask_array 65 { 66 public: 67 typedef _Tp value_type; 68 69 // _GLIBCXX_RESOLVE_LIB_DEFECTS 70 // 253. valarray helper functions are almost entirely useless 71 72 /// Copy constructor. Both slices refer to the same underlying array. 73 mask_array (const mask_array&); 74 75 /// Assignment operator. Assigns elements to corresponding elements 76 /// of @a a. 77 mask_array& operator=(const mask_array&); 78 79 void operator=(const valarray<_Tp>&) const; 80 /// Multiply slice elements by corresponding elements of @a v. 81 void operator*=(const valarray<_Tp>&) const; 82 /// Divide slice elements by corresponding elements of @a v. 83 void operator/=(const valarray<_Tp>&) const; 84 /// Modulo slice elements by corresponding elements of @a v. 85 void operator%=(const valarray<_Tp>&) const; 86 /// Add corresponding elements of @a v to slice elements. 87 void operator+=(const valarray<_Tp>&) const; 88 /// Subtract corresponding elements of @a v from slice elements. 89 void operator-=(const valarray<_Tp>&) const; 90 /// Logical xor slice elements with corresponding elements of @a v. 91 void operator^=(const valarray<_Tp>&) const; 92 /// Logical and slice elements with corresponding elements of @a v. 93 void operator&=(const valarray<_Tp>&) const; 94 /// Logical or slice elements with corresponding elements of @a v. 95 void operator|=(const valarray<_Tp>&) const; 96 /// Left shift slice elements by corresponding elements of @a v. 97 void operator<<=(const valarray<_Tp>&) const; 98 /// Right shift slice elements by corresponding elements of @a v. 99 void operator>>=(const valarray<_Tp>&) const; 100 /// Assign all slice elements to @a t. 101 void operator=(const _Tp&) const; 102 103 // ~mask_array (); 104 105 template<class _Dom> 106 void operator=(const _Expr<_Dom,_Tp>&) const; 107 template<class _Dom> 108 void operator*=(const _Expr<_Dom,_Tp>&) const; 109 template<class _Dom> 110 void operator/=(const _Expr<_Dom,_Tp>&) const; 111 template<class _Dom> 112 void operator%=(const _Expr<_Dom,_Tp>&) const; 113 template<class _Dom> 114 void operator+=(const _Expr<_Dom,_Tp>&) const; 115 template<class _Dom> 116 void operator-=(const _Expr<_Dom,_Tp>&) const; 117 template<class _Dom> 118 void operator^=(const _Expr<_Dom,_Tp>&) const; 119 template<class _Dom> 120 void operator&=(const _Expr<_Dom,_Tp>&) const; 121 template<class _Dom> 122 void operator|=(const _Expr<_Dom,_Tp>&) const; 123 template<class _Dom> 124 void operator<<=(const _Expr<_Dom,_Tp>&) const; 125 template<class _Dom> 126 void operator>>=(const _Expr<_Dom,_Tp>&) const; 127 128 private: 129 mask_array(_Array<_Tp>, size_t, _Array<bool>); 130 friend class valarray<_Tp>; 131 132 const size_t _M_sz; 133 const _Array<bool> _M_mask; 134 const _Array<_Tp> _M_array; 135 136 #if __cplusplus < 201103L 137 // not implemented 138 mask_array(); 139 #else 140 public: 141 mask_array() = delete; 142 #endif 143 }; 144 145 template<typename _Tp> 146 inline mask_array<_Tp>::mask_array(const mask_array<_Tp>& __a) 147 : _M_sz(__a._M_sz), _M_mask(__a._M_mask), _M_array(__a._M_array) {} 148 149 template<typename _Tp> 150 inline 151 mask_array<_Tp>::mask_array(_Array<_Tp> __a, size_t __s, _Array<bool> __m) 152 : _M_sz(__s), _M_mask(__m), _M_array(__a) {} 153 154 template<typename _Tp> 155 inline mask_array<_Tp>& 156 mask_array<_Tp>::operator=(const mask_array<_Tp>& __a) 157 { 158 __glibcxx_assert(__a._M_sz == _M_sz); 159 std::__valarray_copy(__a._M_array, __a._M_mask, 160 _M_sz, _M_array, _M_mask); 161 return *this; 162 } 163 164 template<typename _Tp> 165 inline void 166 mask_array<_Tp>::operator=(const _Tp& __t) const 167 { std::__valarray_fill(_M_array, _M_sz, _M_mask, __t); } 168 169 template<typename _Tp> 170 inline void 171 mask_array<_Tp>::operator=(const valarray<_Tp>& __v) const 172 { 173 __glibcxx_assert(__v.size() == _M_sz); 174 std::__valarray_copy(_Array<_Tp>(__v), __v.size(), _M_array, _M_mask); 175 } 176 177 template<typename _Tp> 178 template<class _Ex> 179 inline void 180 mask_array<_Tp>::operator=(const _Expr<_Ex, _Tp>& __e) const 181 { 182 __glibcxx_assert(__e.size() == _M_sz); 183 std::__valarray_copy(__e, __e.size(), _M_array, _M_mask); 184 } 185 186 /// @cond undocumented 187 #undef _DEFINE_VALARRAY_OPERATOR 188 #define _DEFINE_VALARRAY_OPERATOR(_Op, _Name) \ 189 template<typename _Tp> \ 190 inline void \ 191 mask_array<_Tp>::operator _Op##=(const valarray<_Tp>& __v) const \ 192 { \ 193 __glibcxx_assert(__v.size() == _M_sz); \ 194 _Array_augmented_##_Name(_M_array, _M_mask, \ 195 _Array<_Tp>(__v), __v.size()); \ 196 } \ 197 \ 198 template<typename _Tp> \ 199 template<class _Dom> \ 200 inline void \ 201 mask_array<_Tp>::operator _Op##=(const _Expr<_Dom, _Tp>& __e) const\ 202 { \ 203 __glibcxx_assert(__e.size() == _M_sz); \ 204 _Array_augmented_##_Name(_M_array, _M_mask, __e, __e.size()); \ 205 } 206 207 _DEFINE_VALARRAY_OPERATOR(*, __multiplies) 208 _DEFINE_VALARRAY_OPERATOR(/, __divides) 209 _DEFINE_VALARRAY_OPERATOR(%, __modulus) 210 _DEFINE_VALARRAY_OPERATOR(+, __plus) 211 _DEFINE_VALARRAY_OPERATOR(-, __minus) 212 _DEFINE_VALARRAY_OPERATOR(^, __bitwise_xor) 213 _DEFINE_VALARRAY_OPERATOR(&, __bitwise_and) 214 _DEFINE_VALARRAY_OPERATOR(|, __bitwise_or) 215 _DEFINE_VALARRAY_OPERATOR(<<, __shift_left) 216 _DEFINE_VALARRAY_OPERATOR(>>, __shift_right) 217 218 #undef _DEFINE_VALARRAY_OPERATOR 219 /// @endcond 220 221 /// @} group numeric_arrays 222 223 _GLIBCXX_END_NAMESPACE_VERSION 224 } // namespace 225 226 #endif /* _MASK_ARRAY_H */
