1// The template and inlines for the -*- C++ -*- mask_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/mask_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@DPTMaths.ENS-Cachan.Fr> 32 33#ifndef _MASK_ARRAY_H 34#define _MASK_ARRAY_H 1 35 36#pragma GCC system_header 37 38namespace std _GLIBCXX_VISIBILITY(default) 39{ 40_GLIBCXX_BEGIN_NAMESPACE_VERSION 41 42 /** 43 * @addtogroup numeric_arrays 44 * @{ 45 */ 46 47 /** 48 * @brief Reference to selected subset of an array. 49 * 50 * A mask_array is a reference to the actual elements of an array specified 51 * by a bitmask in the form of an array of bool. The way to get a 52 * mask_array is to call operator[](valarray<bool>) on a valarray. The 53 * returned mask_array then permits carrying operations out on the 54 * referenced subset of elements in the original valarray. 55 * 56 * For example, if a mask_array is obtained using the array (false, true, 57 * false, true) as an argument, the mask array has two elements referring 58 * to array[1] and array[3] in the underlying array. 59 * 60 * @param Tp Element type. 61 */ 62 template <class _Tp> 63 class mask_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 mask_array (const mask_array&); 73 74 /// Assignment operator. Assigns elements to corresponding elements 75 /// of @a a. 76 mask_array& operator=(const mask_array&); 77 78 void operator=(const valarray<_Tp>&) const; 79 /// Multiply slice elements by corresponding elements of @a v. 80 void operator*=(const valarray<_Tp>&) const; 81 /// Divide slice elements by corresponding elements of @a v. 82 void operator/=(const valarray<_Tp>&) const; 83 /// Modulo slice elements by corresponding elements of @a v. 84 void operator%=(const valarray<_Tp>&) const; 85 /// Add corresponding elements of @a v to slice elements. 86 void operator+=(const valarray<_Tp>&) const; 87 /// Subtract corresponding elements of @a v from slice elements. 88 void operator-=(const valarray<_Tp>&) const; 89 /// Logical xor slice elements with corresponding elements of @a v. 90 void operator^=(const valarray<_Tp>&) const; 91 /// Logical and slice elements with corresponding elements of @a v. 92 void operator&=(const valarray<_Tp>&) const; 93 /// Logical or slice elements with corresponding elements of @a v. 94 void operator|=(const valarray<_Tp>&) const; 95 /// Left shift slice elements by corresponding elements of @a v. 96 void operator<<=(const valarray<_Tp>&) const; 97 /// Right shift slice elements by corresponding elements of @a v. 98 void operator>>=(const valarray<_Tp>&) const; 99 /// Assign all slice elements to @a t. 100 void operator=(const _Tp&) const; 101 102 // ~mask_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 mask_array(_Array<_Tp>, size_t, _Array<bool>); 129 friend class valarray<_Tp>; 130 131 const size_t _M_sz; 132 const _Array<bool> _M_mask; 133 const _Array<_Tp> _M_array; 134 135 // not implemented 136 mask_array(); 137 }; 138 139 template<typename _Tp> 140 inline mask_array<_Tp>::mask_array(const mask_array<_Tp>& a) 141 : _M_sz(a._M_sz), _M_mask(a._M_mask), _M_array(a._M_array) {} 142 143 template<typename _Tp> 144 inline 145 mask_array<_Tp>::mask_array(_Array<_Tp> __a, size_t __s, _Array<bool> __m) 146 : _M_sz(__s), _M_mask(__m), _M_array(__a) {} 147 148 template<typename _Tp> 149 inline mask_array<_Tp>& 150 mask_array<_Tp>::operator=(const mask_array<_Tp>& __a) 151 { 152 std::__valarray_copy(__a._M_array, __a._M_mask, 153 _M_sz, _M_array, _M_mask); 154 return *this; 155 } 156 157 template<typename _Tp> 158 inline void 159 mask_array<_Tp>::operator=(const _Tp& __t) const 160 { std::__valarray_fill(_M_array, _M_sz, _M_mask, __t); } 161 162 template<typename _Tp> 163 inline void 164 mask_array<_Tp>::operator=(const valarray<_Tp>& __v) const 165 { std::__valarray_copy(_Array<_Tp>(__v), __v.size(), _M_array, _M_mask); } 166 167 template<typename _Tp> 168 template<class _Ex> 169 inline void 170 mask_array<_Tp>::operator=(const _Expr<_Ex, _Tp>& __e) const 171 { std::__valarray_copy(__e, __e.size(), _M_array, _M_mask); } 172 173#undef _DEFINE_VALARRAY_OPERATOR 174#define _DEFINE_VALARRAY_OPERATOR(_Op, _Name) \ 175 template<typename _Tp> \ 176 inline void \ 177 mask_array<_Tp>::operator _Op##=(const valarray<_Tp>& __v) const \ 178 { \ 179 _Array_augmented_##_Name(_M_array, _M_mask, \ 180 _Array<_Tp>(__v), __v.size()); \ 181 } \ 182 \ 183 template<typename _Tp> \ 184 template<class _Dom> \ 185 inline void \ 186 mask_array<_Tp>::operator _Op##=(const _Expr<_Dom, _Tp>& __e) const\ 187 { \ 188 _Array_augmented_##_Name(_M_array, _M_mask, __e, __e.size()); \ 189 } 190 191_DEFINE_VALARRAY_OPERATOR(*, __multiplies) 192_DEFINE_VALARRAY_OPERATOR(/, __divides) 193_DEFINE_VALARRAY_OPERATOR(%, __modulus) 194_DEFINE_VALARRAY_OPERATOR(+, __plus) 195_DEFINE_VALARRAY_OPERATOR(-, __minus) 196_DEFINE_VALARRAY_OPERATOR(^, __bitwise_xor) 197_DEFINE_VALARRAY_OPERATOR(&, __bitwise_and) 198_DEFINE_VALARRAY_OPERATOR(|, __bitwise_or) 199_DEFINE_VALARRAY_OPERATOR(<<, __shift_left) 200_DEFINE_VALARRAY_OPERATOR(>>, __shift_right) 201 202#undef _DEFINE_VALARRAY_OPERATOR 203 204 // @} group numeric_arrays 205 206_GLIBCXX_END_NAMESPACE_VERSION 207} // namespace 208 209#endif /* _MASK_ARRAY_H */ 210