1// The template and inlines for the -*- C++ -*- mask_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 mask_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 _MASK_ARRAY_H 39#define _MASK_ARRAY_H 1 40 41#pragma GCC system_header 42 43_GLIBCXX_BEGIN_NAMESPACE(std) 44 45 /** 46 * @brief Reference to selected subset of an array. 47 * 48 * A mask_array is a reference to the actual elements of an array specified 49 * by a bitmask in the form of an array of bool. The way to get a 50 * mask_array is to call operator[](valarray<bool>) on a valarray. The 51 * returned mask_array then permits carrying operations out on the 52 * referenced subset of elements in the original valarray. 53 * 54 * For example, if a mask_array is obtained using the array (false, true, 55 * false, true) as an argument, the mask array has two elements referring 56 * to array[1] and array[3] in the underlying array. 57 * 58 * @param Tp Element type. 59 */ 60 template <class _Tp> 61 class mask_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 mask_array (const mask_array&); 71 72 /// Assignment operator. Assigns elements to corresponding elements 73 /// of @a a. 74 mask_array& operator=(const mask_array&); 75 76 void operator=(const valarray<_Tp>&) const; 77 /// Multiply slice elements by corresponding elements of @a v. 78 void operator*=(const valarray<_Tp>&) const; 79 /// Divide slice elements by corresponding elements of @a v. 80 void operator/=(const valarray<_Tp>&) const; 81 /// Modulo slice elements by corresponding elements of @a v. 82 void operator%=(const valarray<_Tp>&) const; 83 /// Add corresponding elements of @a v to slice elements. 84 void operator+=(const valarray<_Tp>&) const; 85 /// Subtract corresponding elements of @a v from slice elements. 86 void operator-=(const valarray<_Tp>&) const; 87 /// Logical xor slice elements with corresponding elements of @a v. 88 void operator^=(const valarray<_Tp>&) const; 89 /// Logical and slice elements with corresponding elements of @a v. 90 void operator&=(const valarray<_Tp>&) const; 91 /// Logical or slice elements with corresponding elements of @a v. 92 void operator|=(const valarray<_Tp>&) const; 93 /// Left shift slice elements by corresponding elements of @a v. 94 void operator<<=(const valarray<_Tp>&) const; 95 /// Right shift slice elements by corresponding elements of @a v. 96 void operator>>=(const valarray<_Tp>&) const; 97 /// Assign all slice elements to @a t. 98 void operator=(const _Tp&) const; 99 100 // ~mask_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 mask_array(_Array<_Tp>, size_t, _Array<bool>); 127 friend class valarray<_Tp>; 128 129 const size_t _M_sz; 130 const _Array<bool> _M_mask; 131 const _Array<_Tp> _M_array; 132 133 // not implemented 134 mask_array(); 135 }; 136 137 template<typename _Tp> 138 inline mask_array<_Tp>::mask_array(const mask_array<_Tp>& a) 139 : _M_sz(a._M_sz), _M_mask(a._M_mask), _M_array(a._M_array) {} 140 141 template<typename _Tp> 142 inline 143 mask_array<_Tp>::mask_array(_Array<_Tp> __a, size_t __s, _Array<bool> __m) 144 : _M_sz(__s), _M_mask(__m), _M_array(__a) {} 145 146 template<typename _Tp> 147 inline mask_array<_Tp>& 148 mask_array<_Tp>::operator=(const mask_array<_Tp>& __a) 149 { 150 std::__valarray_copy(__a._M_array, __a._M_mask, 151 _M_sz, _M_array, _M_mask); 152 return *this; 153 } 154 155 template<typename _Tp> 156 inline void 157 mask_array<_Tp>::operator=(const _Tp& __t) const 158 { std::__valarray_fill(_M_array, _M_sz, _M_mask, __t); } 159 160 template<typename _Tp> 161 inline void 162 mask_array<_Tp>::operator=(const valarray<_Tp>& __v) const 163 { std::__valarray_copy(_Array<_Tp>(__v), __v.size(), _M_array, _M_mask); } 164 165 template<typename _Tp> 166 template<class _Ex> 167 inline void 168 mask_array<_Tp>::operator=(const _Expr<_Ex, _Tp>& __e) const 169 { std::__valarray_copy(__e, __e.size(), _M_array, _M_mask); } 170 171#undef _DEFINE_VALARRAY_OPERATOR 172#define _DEFINE_VALARRAY_OPERATOR(_Op, _Name) \ 173 template<typename _Tp> \ 174 inline void \ 175 mask_array<_Tp>::operator _Op##=(const valarray<_Tp>& __v) const \ 176 { \ 177 _Array_augmented_##_Name(_M_array, _M_mask, \ 178 _Array<_Tp>(__v), __v.size()); \ 179 } \ 180 \ 181 template<typename _Tp> \ 182 template<class _Dom> \ 183 inline void \ 184 mask_array<_Tp>::operator _Op##=(const _Expr<_Dom, _Tp>& __e) const\ 185 { \ 186 _Array_augmented_##_Name(_M_array, _M_mask, __e, __e.size()); \ 187 } 188 189_DEFINE_VALARRAY_OPERATOR(*, __multiplies) 190_DEFINE_VALARRAY_OPERATOR(/, __divides) 191_DEFINE_VALARRAY_OPERATOR(%, __modulus) 192_DEFINE_VALARRAY_OPERATOR(+, __plus) 193_DEFINE_VALARRAY_OPERATOR(-, __minus) 194_DEFINE_VALARRAY_OPERATOR(^, __bitwise_xor) 195_DEFINE_VALARRAY_OPERATOR(&, __bitwise_and) 196_DEFINE_VALARRAY_OPERATOR(|, __bitwise_or) 197_DEFINE_VALARRAY_OPERATOR(<<, __shift_left) 198_DEFINE_VALARRAY_OPERATOR(>>, __shift_right) 199 200#undef _DEFINE_VALARRAY_OPERATOR 201 202_GLIBCXX_END_NAMESPACE 203 204#endif /* _MASK_ARRAY_H */ 205