317 lines
10 KiB
Plaintext
317 lines
10 KiB
Plaintext
|
//---------------------------------------------------------------------------//
|
||
|
|
// Copyright (c) 2013 Kyle Lutz <kyle.r.lutz@gmail.com>
|
||
|
|
//
|
||
|
|
// Distributed under the Boost Software License, Version 1.0
|
||
|
|
// See accompanying file LICENSE_1_0.txt or copy at
|
||
|
|
// http://www.boost.org/LICENSE_1_0.txt
|
||
|
|
//
|
||
|
|
// See http://boostorg.github.com/compute for more information.
|
||
|
|
//---------------------------------------------------------------------------//
|
||
|
|
|
||
|
|
#ifndef BOOST_COMPUTE_ITERATOR_ZIP_ITERATOR_HPP
|
||
|
|
#define BOOST_COMPUTE_ITERATOR_ZIP_ITERATOR_HPP
|
||
|
|
|
||
|
|
#include <cstddef>
|
||
|
|
#include <iterator>
|
||
|
|
|
||
|
|
#include <boost/config.hpp>
|
||
|
|
#include <boost/fusion/algorithm/iteration/for_each.hpp>
|
||
|
|
#include <boost/iterator/iterator_facade.hpp>
|
||
|
|
#include <boost/mpl/back_inserter.hpp>
|
||
|
|
#include <boost/mpl/transform.hpp>
|
||
|
|
#include <boost/mpl/vector.hpp>
|
||
|
|
#include <boost/preprocessor/repetition.hpp>
|
||
|
|
#include <boost/tuple/tuple.hpp>
|
||
|
|
#include <boost/tuple/tuple_comparison.hpp>
|
||
|
|
|
||
|
|
#include <boost/compute/config.hpp>
|
||
|
|
#include <boost/compute/functional.hpp>
|
||
|
|
#include <boost/compute/detail/meta_kernel.hpp>
|
||
|
|
#include <boost/compute/detail/mpl_vector_to_tuple.hpp>
|
||
|
|
#include <boost/compute/types/tuple.hpp>
|
||
|
|
#include <boost/compute/type_traits/is_device_iterator.hpp>
|
||
|
|
#include <boost/compute/type_traits/type_name.hpp>
|
||
|
|
|
||
|
|
namespace boost {
|
||
|
|
namespace compute {
|
||
|
|
|
||
|
|
// forward declaration for zip_iterator
|
||
|
|
template<class IteratorTuple>
|
||
|
|
class zip_iterator;
|
||
|
|
|
||
|
|
namespace detail {
|
||
|
|
|
||
|
|
namespace mpl = boost::mpl;
|
||
|
|
|
||
|
|
// meta-function returning the value_type for an iterator
|
||
|
|
template<class Iterator>
|
||
|
|
struct make_iterator_value_type
|
||
|
|
{
|
||
|
|
typedef typename std::iterator_traits<Iterator>::value_type type;
|
||
|
|
};
|
||
|
|
|
||
|
|
// meta-function returning the value_type for a zip_iterator
|
||
|
|
template<class IteratorTuple>
|
||
|
|
struct make_zip_iterator_value_type
|
||
|
|
{
|
||
|
|
typedef typename
|
||
|
|
detail::mpl_vector_to_tuple<
|
||
|
|
typename mpl::transform<
|
||
|
|
IteratorTuple,
|
||
|
|
make_iterator_value_type<mpl::_1>,
|
||
|
|
mpl::back_inserter<mpl::vector<> >
|
||
|
|
>::type
|
||
|
|
>::type type;
|
||
|
|
};
|
||
|
|
|
||
|
|
// helper class which defines the iterator_facade super-class
|
||
|
|
// type for zip_iterator
|
||
|
|
template<class IteratorTuple>
|
||
|
|
class zip_iterator_base
|
||
|
|
{
|
||
|
|
public:
|
||
|
|
typedef ::boost::iterator_facade<
|
||
|
|
::boost::compute::zip_iterator<IteratorTuple>,
|
||
|
|
typename make_zip_iterator_value_type<IteratorTuple>::type,
|
||
|
|
::std::random_access_iterator_tag,
|
||
|
|
typename make_zip_iterator_value_type<IteratorTuple>::type
|
||
|
|
> type;
|
||
|
|
};
|
||
|
|
|
||
|
|
template<class IteratorTuple, class IndexExpr>
|
||
|
|
struct zip_iterator_index_expr
|
||
|
|
{
|
||
|
|
typedef typename
|
||
|
|
make_zip_iterator_value_type<IteratorTuple>::type
|
||
|
|
result_type;
|
||
|
|
|
||
|
|
zip_iterator_index_expr(const IteratorTuple &iterators,
|
||
|
|
const IndexExpr &index_expr)
|
||
|
|
: m_iterators(iterators),
|
||
|
|
m_index_expr(index_expr)
|
||
|
|
{
|
||
|
|
}
|
||
|
|
|
||
|
|
IteratorTuple m_iterators;
|
||
|
|
IndexExpr m_index_expr;
|
||
|
|
};
|
||
|
|
|
||
|
|
/// \internal_
|
||
|
|
#define BOOST_COMPUTE_PRINT_ELEM(z, n, unused) \
|
||
|
|
BOOST_PP_EXPR_IF(n, << ", ") \
|
||
|
|
<< boost::get<n>(expr.m_iterators)[expr.m_index_expr]
|
||
|
|
|
||
|
|
/// \internal_
|
||
|
|
#define BOOST_COMPUTE_PRINT_ZIP_IDX(z, n, unused) \
|
||
|
|
template<BOOST_PP_ENUM_PARAMS(n, class Iterator), class IndexExpr> \
|
||
|
|
inline meta_kernel& operator<<( \
|
||
|
|
meta_kernel &kernel, \
|
||
|
|
const zip_iterator_index_expr< \
|
||
|
|
boost::tuple<BOOST_PP_ENUM_PARAMS(n, Iterator)>, \
|
||
|
|
IndexExpr \
|
||
|
|
> &expr) \
|
||
|
|
{ \
|
||
|
|
typedef typename \
|
||
|
|
boost::tuple<BOOST_PP_ENUM_PARAMS(n, Iterator)> \
|
||
|
|
tuple_type; \
|
||
|
|
typedef typename \
|
||
|
|
make_zip_iterator_value_type<tuple_type>::type \
|
||
|
|
value_type; \
|
||
|
|
kernel.inject_type<value_type>(); \
|
||
|
|
return kernel \
|
||
|
|
<< "(" << type_name<value_type>() << ")" \
|
||
|
|
<< "{ " \
|
||
|
|
BOOST_PP_REPEAT(n, BOOST_COMPUTE_PRINT_ELEM, ~) \
|
||
|
|
<< "}"; \
|
||
|
|
}
|
||
|
|
|
||
|
|
BOOST_PP_REPEAT_FROM_TO(1, BOOST_COMPUTE_MAX_ARITY, BOOST_COMPUTE_PRINT_ZIP_IDX, ~)
|
||
|
|
|
||
|
|
#undef BOOST_COMPUTE_PRINT_ZIP_IDX
|
||
|
|
#undef BOOST_COMPUTE_PRINT_ELEM
|
||
|
|
|
||
|
|
struct iterator_advancer
|
||
|
|
{
|
||
|
|
iterator_advancer(size_t n)
|
||
|
|
: m_distance(n)
|
||
|
|
{
|
||
|
|
}
|
||
|
|
|
||
|
|
template<class Iterator>
|
||
|
|
void operator()(Iterator &i) const
|
||
|
|
{
|
||
|
|
std::advance(i, m_distance);
|
||
|
|
}
|
||
|
|
|
||
|
|
size_t m_distance;
|
||
|
|
};
|
||
|
|
|
||
|
|
template<class Iterator>
|
||
|
|
void increment_iterator(Iterator &i)
|
||
|
|
{
|
||
|
|
i++;
|
||
|
|
}
|
||
|
|
|
||
|
|
template<class Iterator>
|
||
|
|
void decrement_iterator(Iterator &i)
|
||
|
|
{
|
||
|
|
i--;
|
||
|
|
}
|
||
|
|
|
||
|
|
} // end detail namespace
|
||
|
|
|
||
|
|
/// \class zip_iterator
|
||
|
|
/// \brief A zip iterator adaptor.
|
||
|
|
///
|
||
|
|
/// The zip_iterator class combines values from multiple input iterators. When
|
||
|
|
/// dereferenced it returns a tuple containing each value at the current
|
||
|
|
/// position in each input range.
|
||
|
|
///
|
||
|
|
/// \see make_zip_iterator()
|
||
|
|
template<class IteratorTuple>
|
||
|
|
class zip_iterator : public detail::zip_iterator_base<IteratorTuple>::type
|
||
|
|
{
|
||
|
|
public:
|
||
|
|
typedef typename
|
||
|
|
detail::zip_iterator_base<IteratorTuple>::type
|
||
|
|
super_type;
|
||
|
|
typedef typename super_type::value_type value_type;
|
||
|
|
typedef typename super_type::reference reference;
|
||
|
|
typedef typename super_type::difference_type difference_type;
|
||
|
|
typedef IteratorTuple iterator_tuple;
|
||
|
|
|
||
|
|
zip_iterator(IteratorTuple iterators)
|
||
|
|
: m_iterators(iterators)
|
||
|
|
{
|
||
|
|
}
|
||
|
|
|
||
|
|
zip_iterator(const zip_iterator<IteratorTuple> &other)
|
||
|
|
: m_iterators(other.m_iterators)
|
||
|
|
{
|
||
|
|
}
|
||
|
|
|
||
|
|
zip_iterator<IteratorTuple>&
|
||
|
|
operator=(const zip_iterator<IteratorTuple> &other)
|
||
|
|
{
|
||
|
|
if(this != &other){
|
||
|
|
super_type::operator=(other);
|
||
|
|
|
||
|
|
m_iterators = other.m_iterators;
|
||
|
|
}
|
||
|
|
|
||
|
|
return *this;
|
||
|
|
}
|
||
|
|
|
||
|
|
~zip_iterator()
|
||
|
|
{
|
||
|
|
}
|
||
|
|
|
||
|
|
const IteratorTuple& get_iterator_tuple() const
|
||
|
|
{
|
||
|
|
return m_iterators;
|
||
|
|
}
|
||
|
|
|
||
|
|
template<class IndexExpression>
|
||
|
|
detail::zip_iterator_index_expr<IteratorTuple, IndexExpression>
|
||
|
|
operator[](const IndexExpression &expr) const
|
||
|
|
{
|
||
|
|
return detail::zip_iterator_index_expr<IteratorTuple,
|
||
|
|
IndexExpression>(m_iterators,
|
||
|
|
expr);
|
||
|
|
}
|
||
|
|
|
||
|
|
private:
|
||
|
|
friend class ::boost::iterator_core_access;
|
||
|
|
|
||
|
|
reference dereference() const
|
||
|
|
{
|
||
|
|
return reference();
|
||
|
|
}
|
||
|
|
|
||
|
|
bool equal(const zip_iterator<IteratorTuple> &other) const
|
||
|
|
{
|
||
|
|
return m_iterators == other.m_iterators;
|
||
|
|
}
|
||
|
|
|
||
|
|
void increment()
|
||
|
|
{
|
||
|
|
boost::fusion::for_each(m_iterators, detail::increment_iterator);
|
||
|
|
}
|
||
|
|
|
||
|
|
void decrement()
|
||
|
|
{
|
||
|
|
boost::fusion::for_each(m_iterators, detail::decrement_iterator);
|
||
|
|
}
|
||
|
|
|
||
|
|
void advance(difference_type n)
|
||
|
|
{
|
||
|
|
boost::fusion::for_each(m_iterators, detail::iterator_advancer(n));
|
||
|
|
}
|
||
|
|
|
||
|
|
difference_type distance_to(const zip_iterator<IteratorTuple> &other) const
|
||
|
|
{
|
||
|
|
return std::distance(boost::get<0>(m_iterators),
|
||
|
|
boost::get<0>(other.m_iterators));
|
||
|
|
}
|
||
|
|
|
||
|
|
private:
|
||
|
|
IteratorTuple m_iterators;
|
||
|
|
};
|
||
|
|
|
||
|
|
/// Creates a zip_iterator for \p iterators.
|
||
|
|
///
|
||
|
|
/// \param iterators a tuple of input iterators to zip together
|
||
|
|
///
|
||
|
|
/// \return a \c zip_iterator for \p iterators
|
||
|
|
///
|
||
|
|
/// For example, to zip together iterators from three vectors (\c a, \c b, and
|
||
|
|
/// \p c):
|
||
|
|
/// \code
|
||
|
|
/// auto zipped = boost::compute::make_zip_iterator(
|
||
|
|
/// boost::make_tuple(a.begin(), b.begin(), c.begin())
|
||
|
|
/// );
|
||
|
|
/// \endcode
|
||
|
|
template<class IteratorTuple>
|
||
|
|
inline zip_iterator<IteratorTuple>
|
||
|
|
make_zip_iterator(IteratorTuple iterators)
|
||
|
|
{
|
||
|
|
return zip_iterator<IteratorTuple>(iterators);
|
||
|
|
}
|
||
|
|
|
||
|
|
/// \internal_ (is_device_iterator specialization for zip_iterator)
|
||
|
|
template<class IteratorTuple>
|
||
|
|
struct is_device_iterator<zip_iterator<IteratorTuple> > : boost::true_type {};
|
||
|
|
|
||
|
|
namespace detail {
|
||
|
|
|
||
|
|
// get<N>() specialization for zip_iterator
|
||
|
|
/// \internal_
|
||
|
|
#define BOOST_COMPUTE_ZIP_GET_N(z, n, unused) \
|
||
|
|
template<size_t N, class IteratorTuple, class IndexExpr, \
|
||
|
|
BOOST_PP_ENUM_PARAMS(n, class T)> \
|
||
|
|
inline meta_kernel& \
|
||
|
|
operator<<(meta_kernel &kernel, \
|
||
|
|
const invoked_get< \
|
||
|
|
N, \
|
||
|
|
zip_iterator_index_expr<IteratorTuple, IndexExpr>, \
|
||
|
|
boost::tuple<BOOST_PP_ENUM_PARAMS(n, T)> \
|
||
|
|
> &expr) \
|
||
|
|
{ \
|
||
|
|
typedef typename boost::tuple<BOOST_PP_ENUM_PARAMS(n, T)> Tuple; \
|
||
|
|
typedef typename boost::tuples::element<N, Tuple>::type T; \
|
||
|
|
BOOST_STATIC_ASSERT(N < size_t(boost::tuples::length<Tuple>::value)); \
|
||
|
|
kernel.inject_type<T>(); \
|
||
|
|
return kernel \
|
||
|
|
<< boost::get<N>(expr.m_arg.m_iterators)[expr.m_arg.m_index_expr]; \
|
||
|
|
}
|
||
|
|
|
||
|
|
BOOST_PP_REPEAT_FROM_TO(1, BOOST_COMPUTE_MAX_ARITY, BOOST_COMPUTE_ZIP_GET_N, ~)
|
||
|
|
|
||
|
|
#undef BOOST_COMPUTE_ZIP_GET_N
|
||
|
|
|
||
|
|
} // end detail namespace
|
||
|
|
} // end compute namespace
|
||
|
|
} // end boost namespace
|
||
|
|
|
||
|
|
#endif // BOOST_COMPUTE_ITERATOR_ZIP_ITERATOR_HPP
|