1// The template and inlines for the -*- C++ -*- mask_array class. 2 3// Copyright (C) 1997-2015 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#pragma GCC system_header 36 37namespace std _GLIBCXX_VISIBILITY(default) 38{ 39_GLIBCXX_BEGIN_NAMESPACE_VERSION 40 41 /** 42 * @addtogroup numeric_arrays 43 * @{ 44 */ 45 46 /** 47 * @brief Reference to selected subset of an array. 48 * 49 * A mask_array is a reference to the actual elements of an array specified 50 * by a bitmask in the form of an array of bool. The way to get a 51 * mask_array is to call operator[](valarray<bool>) on a valarray. The 52 * returned mask_array then permits carrying operations out on the 53 * referenced subset of elements in the original valarray. 54 * 55 * For example, if a mask_array is obtained using the array (false, true, 56 * false, true) as an argument, the mask array has two elements referring 57 * to array[1] and array[3] in the underlying array. 58 * 59 * @param Tp Element type. 60 */ 61 template <class _Tp> 62 class mask_array 63 { 64 public: 65 typedef _Tp value_type; 66 67 // _GLIBCXX_RESOLVE_LIB_DEFECTS 68 // 253. valarray helper functions are almost entirely useless 69 70 /// Copy constructor. Both slices refer to the same underlying array. 71 mask_array (const mask_array&); 72 73 /// Assignment operator. Assigns elements to corresponding elements 74 /// of @a a. 75 mask_array& operator=(const mask_array&); 76 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; 100 101 // ~mask_array (); 102 103 template<class _Dom> 104 void operator=(const _Expr<_Dom,_Tp>&) const; 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; 125 126 private: 127 mask_array(_Array<_Tp>, size_t, _Array<bool>); 128 friend class valarray<_Tp>; 129 130 const size_t _M_sz; 131 const _Array<bool> _M_mask; 132 const _Array<_Tp> _M_array; 133 134 // not implemented 135 mask_array(); 136 }; 137 138 template<typename _Tp> 139 inline mask_array<_Tp>::mask_array(const mask_array<_Tp>& a) 140 : _M_sz(a._M_sz), _M_mask(a._M_mask), _M_array(a._M_array) {} 141 142 template<typename _Tp> 143 inline 144 mask_array<_Tp>::mask_array(_Array<_Tp> __a, size_t __s, _Array<bool> __m) 145 : _M_sz(__s), _M_mask(__m), _M_array(__a) {} 146 147 template<typename _Tp> 148 inline mask_array<_Tp>& 149 mask_array<_Tp>::operator=(const mask_array<_Tp>& __a) 150 { 151 std::__valarray_copy(__a._M_array, __a._M_mask, 152 _M_sz, _M_array, _M_mask); 153 return *this; 154 } 155 156 template<typename _Tp> 157 inline void 158 mask_array<_Tp>::operator=(const _Tp& __t) const 159 { std::__valarray_fill(_M_array, _M_sz, _M_mask, __t); } 160 161 template<typename _Tp> 162 inline void 163 mask_array<_Tp>::operator=(const valarray<_Tp>& __v) const 164 { std::__valarray_copy(_Array<_Tp>(__v), __v.size(), _M_array, _M_mask); } 165 166 template<typename _Tp> 167 template<class _Ex> 168 inline void 169 mask_array<_Tp>::operator=(const _Expr<_Ex, _Tp>& __e) const 170 { std::__valarray_copy(__e, __e.size(), _M_array, _M_mask); } 171 172#undef _DEFINE_VALARRAY_OPERATOR 173#define _DEFINE_VALARRAY_OPERATOR(_Op, _Name) \ 174 template<typename _Tp> \ 175 inline void \ 176 mask_array<_Tp>::operator _Op##=(const valarray<_Tp>& __v) const \ 177 { \ 178 _Array_augmented_##_Name(_M_array, _M_mask, \ 179 _Array<_Tp>(__v), __v.size()); \ 180 } \ 181 \ 182 template<typename _Tp> \ 183 template<class _Dom> \ 184 inline void \ 185 mask_array<_Tp>::operator _Op##=(const _Expr<_Dom, _Tp>& __e) const\ 186 { \ 187 _Array_augmented_##_Name(_M_array, _M_mask, __e, __e.size()); \ 188 } 189 190_DEFINE_VALARRAY_OPERATOR(*, __multiplies) 191_DEFINE_VALARRAY_OPERATOR(/, __divides) 192_DEFINE_VALARRAY_OPERATOR(%, __modulus) 193_DEFINE_VALARRAY_OPERATOR(+, __plus) 194_DEFINE_VALARRAY_OPERATOR(-, __minus) 195_DEFINE_VALARRAY_OPERATOR(^, __bitwise_xor) 196_DEFINE_VALARRAY_OPERATOR(&, __bitwise_and) 197_DEFINE_VALARRAY_OPERATOR(|, __bitwise_or) 198_DEFINE_VALARRAY_OPERATOR(<<, __shift_left) 199_DEFINE_VALARRAY_OPERATOR(>>, __shift_right) 200 201#undef _DEFINE_VALARRAY_OPERATOR 202 203 // @} group numeric_arrays 204 205_GLIBCXX_END_NAMESPACE_VERSION 206} // namespace 207 208#endif /* _MASK_ARRAY_H */ 209