11.2.0/bits/slice_array.h

// The template and inlines for the -*- C++ -*- slice_array class.

// Copyright (C) 1997-2021 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.

// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
// <http://www.gnu.org/licenses/>.

/** @file bits/slice_array.h
 *  This is an internal header file, included by other library headers.
 *  Do not attempt to use it directly. @headername{valarray}
 */

// Written by Gabriel Dos Reis <Gabriel.Dos-Reis@DPTMaths.ENS-Cachan.Fr>

#ifndef _SLICE_ARRAY_H
#define _SLICE_ARRAY_H 1

#pragma GCC system_header

namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION

  /**
   * @addtogroup numeric_arrays
   * @{
   */

  /**
   *  @brief  Class defining one-dimensional subset of an array.
   *
   *  The slice class represents a one-dimensional subset of an array,
   *  specified by three parameters: start offset, size, and stride.  The
   *  start offset is the index of the first element of the array that is part
   *  of the subset.  The size is the total number of elements in the subset.
   *  Stride is the distance between each successive array element to include
   *  in the subset.
   *
   *  For example, with an array of size 10, and a slice with offset 1, size 3
   *  and stride 2, the subset consists of array elements 1, 3, and 5.
   */
  class slice
  {
  public:
    ///  Construct an empty slice.
    slice();

    /**
     *  @brief  Construct a slice.
     *
     *  @param  __o  Offset in array of first element.
     *  @param  __d  Number of elements in slice.
     *  @param  __s  Stride between array elements.
     */
    slice(size_t __o, size_t __d, size_t __s);

    ///  Return array offset of first slice element.
    size_t start() const;
    ///  Return size of slice.
    size_t size() const;
    ///  Return array stride of slice.
    size_t stride() const;

#if __cpp_impl_three_way_comparison >= 201907L
    /// Equality comparison
    friend bool operator==(const slice&, const slice&) = default;
#endif

  private:
    size_t _M_off;                      // offset
    size_t _M_sz;                       // size
    size_t _M_st;                       // stride unit
  };

  // _GLIBCXX_RESOLVE_LIB_DEFECTS
  // 543. valarray slice default constructor
  inline
  slice::slice() 
  : _M_off(0), _M_sz(0), _M_st(0) {}

  inline
  slice::slice(size_t __o, size_t __d, size_t __s)
  : _M_off(__o), _M_sz(__d), _M_st(__s) {}

  inline size_t
  slice::start() const
  { return _M_off; }

  inline size_t
  slice::size() const
  { return _M_sz; }

  inline size_t
  slice::stride() const
  { return _M_st; }

  /**
   *  @brief  Reference to one-dimensional subset of an array.
   *
   *  A slice_array is a reference to the actual elements of an array
   *  specified by a slice.  The way to get a slice_array is to call
   *  operator[](slice) on a valarray.  The returned slice_array then permits
   *  carrying operations out on the referenced subset of elements in the
   *  original valarray.  For example, operator+=(valarray) will add values
   *  to the subset of elements in the underlying valarray this slice_array
   *  refers to.
   *
   *  @param  Tp  Element type.
   */
  template<typename _Tp>
    class slice_array
    {
    public:
      typedef _Tp value_type;

      // _GLIBCXX_RESOLVE_LIB_DEFECTS
      // 253. valarray helper functions are almost entirely useless

      ///  Copy constructor.  Both slices refer to the same underlying array.
      slice_array(const slice_array&);

      ///  Assignment operator.  Assigns slice elements to corresponding
      ///  elements of @a a.
      slice_array& operator=(const slice_array&);

      ///  Assign slice elements to corresponding elements of @a v.
      void operator=(const valarray<_Tp>&) const;
      ///  Multiply slice elements by corresponding elements of @a v.
      void operator*=(const valarray<_Tp>&) const;
      ///  Divide slice elements by corresponding elements of @a v.
      void operator/=(const valarray<_Tp>&) const;
      ///  Modulo slice elements by corresponding elements of @a v.
      void operator%=(const valarray<_Tp>&) const;
      ///  Add corresponding elements of @a v to slice elements.
      void operator+=(const valarray<_Tp>&) const;
      ///  Subtract corresponding elements of @a v from slice elements.
      void operator-=(const valarray<_Tp>&) const;
      ///  Logical xor slice elements with corresponding elements of @a v.
      void operator^=(const valarray<_Tp>&) const;
      ///  Logical and slice elements with corresponding elements of @a v.
      void operator&=(const valarray<_Tp>&) const;
      ///  Logical or slice elements with corresponding elements of @a v.
      void operator|=(const valarray<_Tp>&) const;
      ///  Left shift slice elements by corresponding elements of @a v.
      void operator<<=(const valarray<_Tp>&) const;
      ///  Right shift slice elements by corresponding elements of @a v.
      void operator>>=(const valarray<_Tp>&) const;
      ///  Assign all slice elements to @a t.
      void operator=(const _Tp &) const;
      //        ~slice_array ();

      template<class _Dom>
        void operator=(const _Expr<_Dom, _Tp>&) const;
      template<class _Dom>
        void operator*=(const _Expr<_Dom, _Tp>&) const;
      template<class _Dom>
        void operator/=(const _Expr<_Dom, _Tp>&) const;
      template<class _Dom>
        void operator%=(const _Expr<_Dom, _Tp>&) const;
      template<class _Dom>
        void operator+=(const _Expr<_Dom, _Tp>&) const;
      template<class _Dom>
        void operator-=(const _Expr<_Dom, _Tp>&) const;
      template<class _Dom>
        void operator^=(const _Expr<_Dom, _Tp>&) const;
      template<class _Dom>
        void operator&=(const _Expr<_Dom, _Tp>&) const;
      template<class _Dom>
        void operator|=(const _Expr<_Dom, _Tp>&) const;
      template<class _Dom>
        void operator<<=(const _Expr<_Dom, _Tp>&) const;
      template<class _Dom>
        void operator>>=(const _Expr<_Dom, _Tp>&) const;

    private:
      friend class valarray<_Tp>;
      slice_array(_Array<_Tp>, const slice&);

      const size_t      _M_sz;
      const size_t      _M_stride;
      const _Array<_Tp> _M_array;

#if __cplusplus < 201103L
      // not implemented
      slice_array();
#else
    public:
      slice_array() = delete;
#endif
    };

  template<typename _Tp>
    inline
    slice_array<_Tp>::slice_array(_Array<_Tp> __a, const slice& __s)
    : _M_sz(__s.size()), _M_stride(__s.stride()),
      _M_array(__a.begin() + __s.start()) {}

  template<typename _Tp>
    inline
    slice_array<_Tp>::slice_array(const slice_array<_Tp>& __a)
    : _M_sz(__a._M_sz), _M_stride(__a._M_stride), _M_array(__a._M_array) {}

  //    template<typename _Tp>
  //    inline slice_array<_Tp>::~slice_array () {}

  template<typename _Tp>
    inline slice_array<_Tp>&
    slice_array<_Tp>::operator=(const slice_array<_Tp>& __a)
    {
      std::__valarray_copy(__a._M_array, __a._M_sz, __a._M_stride,
                           _M_array, _M_stride);
      return *this;
    }

  template<typename _Tp>
    inline void
    slice_array<_Tp>::operator=(const _Tp& __t) const
    { std::__valarray_fill(_M_array, _M_sz, _M_stride, __t); }

  template<typename _Tp>
    inline void
    slice_array<_Tp>::operator=(const valarray<_Tp>& __v) const
    { std::__valarray_copy(_Array<_Tp>(__v), _M_array, _M_sz, _M_stride); }

  template<typename _Tp>
  template<class _Dom>
    inline void
    slice_array<_Tp>::operator=(const _Expr<_Dom,_Tp>& __e) const
    { std::__valarray_copy(__e, _M_sz, _M_array, _M_stride); }

#undef _DEFINE_VALARRAY_OPERATOR
#define _DEFINE_VALARRAY_OPERATOR(_Op,_Name)                            \
  template<typename _Tp>                                                \
    inline void                                                         \
    slice_array<_Tp>::operator _Op##=(const valarray<_Tp>& __v) const   \
    {                                                                   \
      _Array_augmented_##_Name(_M_array, _M_sz, _M_stride, _Array<_Tp>(__v));\
    }                                                                   \
                                                                        \
  template<typename _Tp>                                                \
    template<class _Dom>                                                \
      inline void                                                       \
      slice_array<_Tp>::operator _Op##=(const _Expr<_Dom,_Tp>& __e) const\
      {                                                                 \
          _Array_augmented_##_Name(_M_array, _M_stride, __e, _M_sz);    \
      }


_DEFINE_VALARRAY_OPERATOR(*, __multiplies)
_DEFINE_VALARRAY_OPERATOR(/, __divides)
_DEFINE_VALARRAY_OPERATOR(%, __modulus)
_DEFINE_VALARRAY_OPERATOR(+, __plus)
_DEFINE_VALARRAY_OPERATOR(-, __minus)
_DEFINE_VALARRAY_OPERATOR(^, __bitwise_xor)
_DEFINE_VALARRAY_OPERATOR(&, __bitwise_and)
_DEFINE_VALARRAY_OPERATOR(|, __bitwise_or)
_DEFINE_VALARRAY_OPERATOR(<<, __shift_left)
_DEFINE_VALARRAY_OPERATOR(>>, __shift_right)

#undef _DEFINE_VALARRAY_OPERATOR

  /// @} group numeric_arrays

_GLIBCXX_END_NAMESPACE_VERSION
} // namespace

#endif /* _SLICE_ARRAY_H */
Revision:	1166
Committed:	Tue Oct 26 14:22:36 2021 UTC (4 years ago) by rossy
Content type:	text/x-chdr
File size:	9579 byte(s)
Log Message:	Daodan: Replace MinGW build env with an up-to-date MSYS2 env
#	Content
1	// The template and inlines for the -- C++ -- slice_array class.
2
3	// Copyright (C) 1997-2021 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/slice_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 _SLICE_ARRAY_H
33	#define _SLICE_ARRAY_H 1
34
35	#pragma GCC system_header
36
37	namespace std _GLIBCXX_VISIBILITY(default)
38	{
39	_GLIBCXX_BEGIN_NAMESPACE_VERSION
40
41	/**
42	* @addtogroup numeric_arrays
43	* @{
44	*/
45
46	/**
47	* @brief Class defining one-dimensional subset of an array.
48	*
49	* The slice class represents a one-dimensional subset of an array,
50	* specified by three parameters: start offset, size, and stride. The
51	* start offset is the index of the first element of the array that is part
52	* of the subset. The size is the total number of elements in the subset.
53	* Stride is the distance between each successive array element to include
54	* in the subset.
55	*
56	* For example, with an array of size 10, and a slice with offset 1, size 3
57	* and stride 2, the subset consists of array elements 1, 3, and 5.
58	*/
59	class slice
60	{
61	public:
62	/// Construct an empty slice.
63	slice();
64
65	/**
66	* @brief Construct a slice.
67	*
68	* @param __o Offset in array of first element.
69	* @param __d Number of elements in slice.
70	* @param __s Stride between array elements.
71	*/
72	slice(size_t __o, size_t __d, size_t __s);
73
74	/// Return array offset of first slice element.
75	size_t start() const;
76	/// Return size of slice.
77	size_t size() const;
78	/// Return array stride of slice.
79	size_t stride() const;
80
81	#if __cpp_impl_three_way_comparison >= 201907L
82	/// Equality comparison
83	friend bool operator==(const slice&, const slice&) = default;
84	#endif
85
86	private:
87	size_t _M_off; // offset
88	size_t _M_sz; // size
89	size_t _M_st; // stride unit
90	};
91
92	// _GLIBCXX_RESOLVE_LIB_DEFECTS
93	// 543. valarray slice default constructor
94	inline
95	slice::slice()
96	: _M_off(0), _M_sz(0), _M_st(0) {}
97
98	inline
99	slice::slice(size_t __o, size_t __d, size_t __s)
100	: _M_off(__o), _M_sz(__d), _M_st(__s) {}
101
102	inline size_t
103	slice::start() const
104	{ return _M_off; }
105
106	inline size_t
107	slice::size() const
108	{ return _M_sz; }
109
110	inline size_t
111	slice::stride() const
112	{ return _M_st; }
113
114	/**
115	* @brief Reference to one-dimensional subset of an array.
116	*
117	* A slice_array is a reference to the actual elements of an array
118	* specified by a slice. The way to get a slice_array is to call
119	* operator[](slice) on a valarray. The returned slice_array then permits
120	* carrying operations out on the referenced subset of elements in the
121	* original valarray. For example, operator+=(valarray) will add values
122	* to the subset of elements in the underlying valarray this slice_array
123	* refers to.
124	*
125	* @param Tp Element type.
126	*/
127	template<typename _Tp>
128	class slice_array
129	{
130	public:
131	typedef _Tp value_type;
132
133	// _GLIBCXX_RESOLVE_LIB_DEFECTS
134	// 253. valarray helper functions are almost entirely useless
135
136	/// Copy constructor. Both slices refer to the same underlying array.
137	slice_array(const slice_array&);
138
139	/// Assignment operator. Assigns slice elements to corresponding
140	/// elements of @a a.
141	slice_array& operator=(const slice_array&);
142
143	/// Assign slice elements to corresponding elements of @a v.
144	void operator=(const valarray<_Tp>&) const;
145	/// Multiply slice elements by corresponding elements of @a v.
146	void operator*=(const valarray<_Tp>&) const;
147	/// Divide slice elements by corresponding elements of @a v.
148	void operator/=(const valarray<_Tp>&) const;
149	/// Modulo slice elements by corresponding elements of @a v.
150	void operator%=(const valarray<_Tp>&) const;
151	/// Add corresponding elements of @a v to slice elements.
152	void operator+=(const valarray<_Tp>&) const;
153	/// Subtract corresponding elements of @a v from slice elements.
154	void operator-=(const valarray<_Tp>&) const;
155	/// Logical xor slice elements with corresponding elements of @a v.
156	void operator^=(const valarray<_Tp>&) const;
157	/// Logical and slice elements with corresponding elements of @a v.
158	void operator&=(const valarray<_Tp>&) const;
159	/// Logical or slice elements with corresponding elements of @a v.
160	void operator\|=(const valarray<_Tp>&) const;
161	/// Left shift slice elements by corresponding elements of @a v.
162	void operator<<=(const valarray<_Tp>&) const;
163	/// Right shift slice elements by corresponding elements of @a v.
164	void operator>>=(const valarray<_Tp>&) const;
165	/// Assign all slice elements to @a t.
166	void operator=(const _Tp &) const;
167	// ~slice_array ();
168
169	template<class _Dom>
170	void operator=(const _Expr<_Dom, _Tp>&) const;
171	template<class _Dom>
172	void operator*=(const _Expr<_Dom, _Tp>&) const;
173	template<class _Dom>
174	void operator/=(const _Expr<_Dom, _Tp>&) const;
175	template<class _Dom>
176	void operator%=(const _Expr<_Dom, _Tp>&) const;
177	template<class _Dom>
178	void operator+=(const _Expr<_Dom, _Tp>&) const;
179	template<class _Dom>
180	void operator-=(const _Expr<_Dom, _Tp>&) const;
181	template<class _Dom>
182	void operator^=(const _Expr<_Dom, _Tp>&) const;
183	template<class _Dom>
184	void operator&=(const _Expr<_Dom, _Tp>&) const;
185	template<class _Dom>
186	void operator\|=(const _Expr<_Dom, _Tp>&) const;
187	template<class _Dom>
188	void operator<<=(const _Expr<_Dom, _Tp>&) const;
189	template<class _Dom>
190	void operator>>=(const _Expr<_Dom, _Tp>&) const;
191
192	private:
193	friend class valarray<_Tp>;
194	slice_array(_Array<_Tp>, const slice&);
195
196	const size_t _M_sz;
197	const size_t _M_stride;
198	const _Array<_Tp> _M_array;
199
200	#if __cplusplus < 201103L
201	// not implemented
202	slice_array();
203	#else
204	public:
205	slice_array() = delete;
206	#endif
207	};
208
209	template<typename _Tp>
210	inline
211	slice_array<_Tp>::slice_array(_Array<_Tp> __a, const slice& __s)
212	: _M_sz(__s.size()), _M_stride(__s.stride()),
213	_M_array(__a.begin() + __s.start()) {}
214
215	template<typename _Tp>
216	inline
217	slice_array<_Tp>::slice_array(const slice_array<_Tp>& __a)
218	: _M_sz(__a._M_sz), _M_stride(__a._M_stride), _M_array(__a._M_array) {}
219
220	// template<typename _Tp>
221	// inline slice_array<_Tp>::~slice_array () {}
222
223	template<typename _Tp>
224	inline slice_array<_Tp>&
225	slice_array<_Tp>::operator=(const slice_array<_Tp>& __a)
226	{
227	std::__valarray_copy(__a._M_array, __a._M_sz, __a._M_stride,
228	_M_array, _M_stride);
229	return *this;
230	}
231
232	template<typename _Tp>
233	inline void
234	slice_array<_Tp>::operator=(const _Tp& __t) const
235	{ std::__valarray_fill(_M_array, _M_sz, _M_stride, __t); }
236
237	template<typename _Tp>
238	inline void
239	slice_array<_Tp>::operator=(const valarray<_Tp>& __v) const
240	{ std::__valarray_copy(_Array<_Tp>(__v), _M_array, _M_sz, _M_stride); }
241
242	template<typename _Tp>
243	template<class _Dom>
244	inline void
245	slice_array<_Tp>::operator=(const _Expr<_Dom,_Tp>& __e) const
246	{ std::__valarray_copy(__e, _M_sz, _M_array, _M_stride); }
247
248	#undef _DEFINE_VALARRAY_OPERATOR
249	#define _DEFINE_VALARRAY_OPERATOR(_Op,_Name) \
250	template<typename _Tp> \
251	inline void \
252	slice_array<_Tp>::operator _Op##=(const valarray<_Tp>& __v) const \
253	{ \
254	_Array_augmented_##_Name(_M_array, _M_sz, _M_stride, _Array<_Tp>(__v));\
255	} \
256	\
257	template<typename _Tp> \
258	template<class _Dom> \
259	inline void \
260	slice_array<_Tp>::operator _Op##=(const _Expr<_Dom,_Tp>& __e) const\
261	{ \
262	_Array_augmented_##_Name(_M_array, _M_stride, __e, _M_sz); \
263	}
264
265
266	_DEFINE_VALARRAY_OPERATOR(*, __multiplies)
267	_DEFINE_VALARRAY_OPERATOR(/, __divides)
268	_DEFINE_VALARRAY_OPERATOR(%, __modulus)
269	_DEFINE_VALARRAY_OPERATOR(+, __plus)
270	_DEFINE_VALARRAY_OPERATOR(-, __minus)
271	_DEFINE_VALARRAY_OPERATOR(^, __bitwise_xor)
272	_DEFINE_VALARRAY_OPERATOR(&, __bitwise_and)
273	_DEFINE_VALARRAY_OPERATOR(\|, __bitwise_or)
274	_DEFINE_VALARRAY_OPERATOR(<<, __shift_left)
275	_DEFINE_VALARRAY_OPERATOR(>>, __shift_right)
276
277	#undef _DEFINE_VALARRAY_OPERATOR
278
279	/// @} group numeric_arrays
280
281	_GLIBCXX_END_NAMESPACE_VERSION
282	} // namespace
283
284	#endif /* _SLICE_ARRAY_H */