1 // The template and inlines for the -*- C++ -*- indirect_array class. 2 3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2004, 2005 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 2, 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 // You should have received a copy of the GNU General Public License along 18 // with this library; see the file COPYING. If not, write to the Free 19 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 20 // USA. 21 22 // As a special exception, you may use this file as part of a free software 23 // library without restriction. Specifically, if other files instantiate 24 // templates or use macros or inline functions from this file, or you compile 25 // this file and link it with other files to produce an executable, this 26 // file does not by itself cause the resulting executable to be covered by 27 // the GNU General Public License. This exception does not however 28 // invalidate any other reasons why the executable file might be covered by 29 // the GNU General Public License. 30 31 /** @file indirect_array.h 32 * This is an internal header file, included by other library headers. 33 * You should not attempt to use it directly. 34 */ 35 36 // Written by Gabriel Dos Reis <Gabriel.Dos-Reis@DPTMaths.ENS-Cachan.Fr> 37 38 #ifndef _INDIRECT_ARRAY_H 39 #define _INDIRECT_ARRAY_H 1 40 41 #pragma GCC system_header 42 43 _GLIBCXX_BEGIN_NAMESPACE(std) 44 45 /** 46 * @brief Reference to arbitrary subset of an array. 47 * 48 * An indirect_array is a reference to the actual elements of an array 49 * specified by an ordered array of indices. The way to get an 50 * indirect_array is to call operator[](valarray<size_t>) on a valarray. 51 * The returned indirect_array then permits carrying operations out on the 52 * referenced subset of elements in the original valarray. 53 * 54 * For example, if an indirect_array is obtained using the array (4,2,0) as 55 * an argument, and then assigned to an array containing (1,2,3), then the 56 * underlying array will have array[0]==3, array[2]==2, and array[4]==1. 57 * 58 * @param Tp Element type. 59 */ 60 template <class _Tp> 61 class indirect_array 62 { 63 public: 64 typedef _Tp value_type; 65 66 // _GLIBCXX_RESOLVE_LIB_DEFECTS 67 // 253. valarray helper functions are almost entirely useless 68 69 /// Copy constructor. Both slices refer to the same underlying array. 70 indirect_array(const indirect_array&); 71 72 /// Assignment operator. Assigns elements to corresponding elements 73 /// of @a a. 74 indirect_array& operator=(const indirect_array&); 75 76 /// Assign slice elements to corresponding elements of @a v. 77 void operator=(const valarray<_Tp>&) const; 78 /// Multiply slice elements by corresponding elements of @a v. 79 void operator*=(const valarray<_Tp>&) const; 80 /// Divide slice elements by corresponding elements of @a v. 81 void operator/=(const valarray<_Tp>&) const; 82 /// Modulo slice elements by corresponding elements of @a v. 83 void operator%=(const valarray<_Tp>&) const; 84 /// Add corresponding elements of @a v to slice elements. 85 void operator+=(const valarray<_Tp>&) const; 86 /// Subtract corresponding elements of @a v from slice elements. 87 void operator-=(const valarray<_Tp>&) const; 88 /// Logical xor slice elements with corresponding elements of @a v. 89 void operator^=(const valarray<_Tp>&) const; 90 /// Logical and slice elements with corresponding elements of @a v. 91 void operator&=(const valarray<_Tp>&) const; 92 /// Logical or slice elements with corresponding elements of @a v. 93 void operator|=(const valarray<_Tp>&) const; 94 /// Left shift slice elements by corresponding elements of @a v. 95 void operator<<=(const valarray<_Tp>&) const; 96 /// Right shift slice elements by corresponding elements of @a v. 97 void operator>>=(const valarray<_Tp>&) const; 98 /// Assign all slice elements to @a t. 99 void operator= (const _Tp&) const; 100 // ~indirect_array(); 101 102 template<class _Dom> 103 void operator=(const _Expr<_Dom, _Tp>&) const; 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; 124 125 private: 126 /// Copy constructor. Both slices refer to the same underlying array. 127 indirect_array(_Array<_Tp>, size_t, _Array<size_t>); 128 129 friend class valarray<_Tp>; 130 friend class gslice_array<_Tp>; 131 132 const size_t _M_sz; 133 const _Array<size_t> _M_index; 134 const _Array<_Tp> _M_array; 135 136 // not implemented 137 indirect_array(); 138 }; 139 140 template<typename _Tp> 141 inline 142 indirect_array<_Tp>::indirect_array(const indirect_array<_Tp>& __a) 143 : _M_sz(__a._M_sz), _M_index(__a._M_index), _M_array(__a._M_array) {} 144 145 template<typename _Tp> 146 inline 147 indirect_array<_Tp>::indirect_array(_Array<_Tp> __a, size_t __s, 148 _Array<size_t> __i) 149 : _M_sz(__s), _M_index(__i), _M_array(__a) {} 150 151 template<typename _Tp> 152 inline indirect_array<_Tp>& 153 indirect_array<_Tp>::operator=(const indirect_array<_Tp>& __a) 154 { 155 std::__valarray_copy(__a._M_array, _M_sz, __a._M_index, _M_array, 156 _M_index); 157 return *this; 158 } 159 160 template<typename _Tp> 161 inline void 162 indirect_array<_Tp>::operator=(const _Tp& __t) const 163 { std::__valarray_fill(_M_array, _M_index, _M_sz, __t); } 164 165 template<typename _Tp> 166 inline void 167 indirect_array<_Tp>::operator=(const valarray<_Tp>& __v) const 168 { std::__valarray_copy(_Array<_Tp>(__v), _M_sz, _M_array, _M_index); } 169 170 template<typename _Tp> 171 template<class _Dom> 172 inline void 173 indirect_array<_Tp>::operator=(const _Expr<_Dom, _Tp>& __e) const 174 { std::__valarray_copy(__e, _M_sz, _M_array, _M_index); } 175 176 #undef _DEFINE_VALARRAY_OPERATOR 177 #define _DEFINE_VALARRAY_OPERATOR(_Op, _Name) \ 178 template<typename _Tp> \ 179 inline void \ 180 indirect_array<_Tp>::operator _Op##=(const valarray<_Tp>& __v) const\ 181 { \ 182 _Array_augmented_##_Name(_M_array, _M_index, _Array<_Tp>(__v), _M_sz); \ 183 } \ 184 \ 185 template<typename _Tp> \ 186 template<class _Dom> \ 187 inline void \ 188 indirect_array<_Tp>::operator _Op##=(const _Expr<_Dom,_Tp>& __e) const\ 189 { \ 190 _Array_augmented_##_Name(_M_array, _M_index, __e, _M_sz); \ 191 } 192 193 _DEFINE_VALARRAY_OPERATOR(*, __multiplies) 194 _DEFINE_VALARRAY_OPERATOR(/, __divides) 195 _DEFINE_VALARRAY_OPERATOR(%, __modulus) 196 _DEFINE_VALARRAY_OPERATOR(+, __plus) 197 _DEFINE_VALARRAY_OPERATOR(-, __minus) 198 _DEFINE_VALARRAY_OPERATOR(^, __bitwise_xor) 199 _DEFINE_VALARRAY_OPERATOR(&, __bitwise_and) 200 _DEFINE_VALARRAY_OPERATOR(|, __bitwise_or) 201 _DEFINE_VALARRAY_OPERATOR(<<, __shift_left) 202 _DEFINE_VALARRAY_OPERATOR(>>, __shift_right) 203 204 #undef _DEFINE_VALARRAY_OPERATOR 205 206 _GLIBCXX_END_NAMESPACE 207 208 #endif /* _INDIRECT_ARRAY_H */ 209