1 // The template and inlines for the -*- C++ -*- indirect_array class. 2 3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2004, 2005, 2009, 2010 4 // Free Software Foundation, Inc. 5 // 6 // This file is part of the GNU ISO C++ Library. This library is free 7 // software; you can redistribute it and/or modify it under the 8 // terms of the GNU General Public License as published by the 9 // Free Software Foundation; either version 3, or (at your option) 10 // any later version. 11 12 // This library is distributed in the hope that it will be useful, 13 // but WITHOUT ANY WARRANTY; without even the implied warranty of 14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 // GNU General Public License for more details. 16 17 // Under Section 7 of GPL version 3, you are granted additional 18 // permissions described in the GCC Runtime Library Exception, version 19 // 3.1, as published by the Free Software Foundation. 20 21 // You should have received a copy of the GNU General Public License and 22 // a copy of the GCC Runtime Library Exception along with this program; 23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 24 // <http://www.gnu.org/licenses/>. 25 26 /** @file bits/indirect_array.h 27 * This is an internal header file, included by other library headers. 28 * Do not attempt to use it directly. @headername{valarray} 29 */ 30 31 // Written by Gabriel Dos Reis <Gabriel.Dos-Reis (at) DPTMaths.ENS-Cachan.Fr> 32 33 #ifndef _INDIRECT_ARRAY_H 34 #define _INDIRECT_ARRAY_H 1 35 36 #pragma GCC system_header 37 38 namespace std _GLIBCXX_VISIBILITY(default) 39 { 40 _GLIBCXX_BEGIN_NAMESPACE_VERSION 41 42 /** 43 * @addtogroup numeric_arrays 44 * @{ 45 */ 46 47 /** 48 * @brief Reference to arbitrary subset of an array. 49 * 50 * An indirect_array is a reference to the actual elements of an array 51 * specified by an ordered array of indices. The way to get an 52 * indirect_array is to call operator[](valarray<size_t>) on a valarray. 53 * The returned indirect_array then permits carrying operations out on the 54 * referenced subset of elements in the original valarray. 55 * 56 * For example, if an indirect_array is obtained using the array (4,2,0) as 57 * an argument, and then assigned to an array containing (1,2,3), then the 58 * underlying array will have array[0]==3, array[2]==2, and array[4]==1. 59 * 60 * @param Tp Element type. 61 */ 62 template <class _Tp> 63 class indirect_array 64 { 65 public: 66 typedef _Tp value_type; 67 68 // _GLIBCXX_RESOLVE_LIB_DEFECTS 69 // 253. valarray helper functions are almost entirely useless 70 71 /// Copy constructor. Both slices refer to the same underlying array. 72 indirect_array(const indirect_array&); 73 74 /// Assignment operator. Assigns elements to corresponding elements 75 /// of @a a. 76 indirect_array& operator=(const indirect_array&); 77 78 /// Assign slice elements to corresponding elements of @a v. 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 // ~indirect_array(); 103 104 template<class _Dom> 105 void operator=(const _Expr<_Dom, _Tp>&) const; 106 template<class _Dom> 107 void operator*=(const _Expr<_Dom, _Tp>&) const; 108 template<class _Dom> 109 void operator/=(const _Expr<_Dom, _Tp>&) const; 110 template<class _Dom> 111 void operator%=(const _Expr<_Dom, _Tp>&) const; 112 template<class _Dom> 113 void operator+=(const _Expr<_Dom, _Tp>&) const; 114 template<class _Dom> 115 void operator-=(const _Expr<_Dom, _Tp>&) const; 116 template<class _Dom> 117 void operator^=(const _Expr<_Dom, _Tp>&) const; 118 template<class _Dom> 119 void operator&=(const _Expr<_Dom, _Tp>&) const; 120 template<class _Dom> 121 void operator|=(const _Expr<_Dom, _Tp>&) const; 122 template<class _Dom> 123 void operator<<=(const _Expr<_Dom, _Tp>&) const; 124 template<class _Dom> 125 void operator>>=(const _Expr<_Dom, _Tp>&) const; 126 127 private: 128 /// Copy constructor. Both slices refer to the same underlying array. 129 indirect_array(_Array<_Tp>, size_t, _Array<size_t>); 130 131 friend class valarray<_Tp>; 132 friend class gslice_array<_Tp>; 133 134 const size_t _M_sz; 135 const _Array<size_t> _M_index; 136 const _Array<_Tp> _M_array; 137 138 // not implemented 139 indirect_array(); 140 }; 141 142 template<typename _Tp> 143 inline 144 indirect_array<_Tp>::indirect_array(const indirect_array<_Tp>& __a) 145 : _M_sz(__a._M_sz), _M_index(__a._M_index), _M_array(__a._M_array) {} 146 147 template<typename _Tp> 148 inline 149 indirect_array<_Tp>::indirect_array(_Array<_Tp> __a, size_t __s, 150 _Array<size_t> __i) 151 : _M_sz(__s), _M_index(__i), _M_array(__a) {} 152 153 template<typename _Tp> 154 inline indirect_array<_Tp>& 155 indirect_array<_Tp>::operator=(const indirect_array<_Tp>& __a) 156 { 157 std::__valarray_copy(__a._M_array, _M_sz, __a._M_index, _M_array, 158 _M_index); 159 return *this; 160 } 161 162 template<typename _Tp> 163 inline void 164 indirect_array<_Tp>::operator=(const _Tp& __t) const 165 { std::__valarray_fill(_M_array, _M_index, _M_sz, __t); } 166 167 template<typename _Tp> 168 inline void 169 indirect_array<_Tp>::operator=(const valarray<_Tp>& __v) const 170 { std::__valarray_copy(_Array<_Tp>(__v), _M_sz, _M_array, _M_index); } 171 172 template<typename _Tp> 173 template<class _Dom> 174 inline void 175 indirect_array<_Tp>::operator=(const _Expr<_Dom, _Tp>& __e) const 176 { std::__valarray_copy(__e, _M_sz, _M_array, _M_index); } 177 178 #undef _DEFINE_VALARRAY_OPERATOR 179 #define _DEFINE_VALARRAY_OPERATOR(_Op, _Name) \ 180 template<typename _Tp> \ 181 inline void \ 182 indirect_array<_Tp>::operator _Op##=(const valarray<_Tp>& __v) const\ 183 { \ 184 _Array_augmented_##_Name(_M_array, _M_index, _Array<_Tp>(__v), _M_sz); \ 185 } \ 186 \ 187 template<typename _Tp> \ 188 template<class _Dom> \ 189 inline void \ 190 indirect_array<_Tp>::operator _Op##=(const _Expr<_Dom,_Tp>& __e) const\ 191 { \ 192 _Array_augmented_##_Name(_M_array, _M_index, __e, _M_sz); \ 193 } 194 195 _DEFINE_VALARRAY_OPERATOR(*, __multiplies) 196 _DEFINE_VALARRAY_OPERATOR(/, __divides) 197 _DEFINE_VALARRAY_OPERATOR(%, __modulus) 198 _DEFINE_VALARRAY_OPERATOR(+, __plus) 199 _DEFINE_VALARRAY_OPERATOR(-, __minus) 200 _DEFINE_VALARRAY_OPERATOR(^, __bitwise_xor) 201 _DEFINE_VALARRAY_OPERATOR(&, __bitwise_and) 202 _DEFINE_VALARRAY_OPERATOR(|, __bitwise_or) 203 _DEFINE_VALARRAY_OPERATOR(<<, __shift_left) 204 _DEFINE_VALARRAY_OPERATOR(>>, __shift_right) 205 206 #undef _DEFINE_VALARRAY_OPERATOR 207 208 // @} group numeric_arrays 209 210 _GLIBCXX_END_NAMESPACE_VERSION 211 } // namespace 212 213 #endif /* _INDIRECT_ARRAY_H */ 214