gcc/libstdc++-v3/include/bits/slice_array.h
Jonathan Wakely 1b749ae95e PR libstdc++/83860 avoid dangling references in valarray closure types
Store nested closures by value not by reference, to prevent holding
invalid references to temporaries that have been destroyed. This
changes the layout of the closure types, so change their linkage names,
but moving them to a different namespace.

	PR libstdc++/57997
	PR libstdc++/83860
	* include/bits/gslice_array.h (gslice_array): Define default
	constructor as deleted, as per C++11 standard.
	* include/bits/mask_array.h (mask_array): Likewise.
	* include/bits/slice_array.h (slice_array): Likewise.
	* include/bits/valarray_after.h (_GBase, _GClos, _IBase, _IClos): Move
	to namespace __detail.
	(_GBase::_M_expr, _IBase::_M_expr): Use _ValArrayRef for type of data
	members.
	* include/bits/valarray_before.h (_ValArrayRef): New helper for type
	of data members in closure objects.
	(_FunBase, _ValFunClos, _RefFunClos, _UnBase, _UnClos, _BinBase)
	(_BinBase2, _BinBase1, _BinClos, _SBase, _SClos): Move to namespace
	__detail.
	(_FunBase::_M_expr, _UnBase::_M_expr, _BinBase::_M_expr1)
	(_BinBase::_M_expr2, _BinBase2::_M_expr1, _BinBase1::_M_expr2)
	(_SBase::_M_expr): Use _ValArrayRef for type of data members.
	* include/std/valarray (_UnClos, _BinClos, _SClos, _GClos, _IClos)
	(_ValFunClos, _RefFunClos): Move to namespace __detail and add
	using-declarations to namespace std.
	* testsuite/26_numerics/valarray/83860.cc: New.

From-SVN: r259844
2018-05-02 17:41:46 +01:00

280 lines
9.2 KiB
C++

// The template and inlines for the -*- C++ -*- slice_array class.
// Copyright (C) 1997-2018 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;
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 */