add boost on mac

macx64/include/boost/compute/iterator/strided_iterator.hpp

@@ -0,0 +1,298 @@
+//---------------------------------------------------------------------------//
+// Copyright (c) 2015 Jakub Szuppe <j.szuppe@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_STRIDED_ITERATOR_HPP
+#define BOOST_COMPUTE_ITERATOR_STRIDED_ITERATOR_HPP
+
+#include <cstddef>
+#include <iterator>
+
+#include <boost/config.hpp>
+#include <boost/iterator/iterator_adaptor.hpp>
+
+#include <boost/compute/functional.hpp>
+#include <boost/compute/detail/meta_kernel.hpp>
+#include <boost/compute/detail/is_buffer_iterator.hpp>
+#include <boost/compute/detail/read_write_single_value.hpp>
+#include <boost/compute/iterator/detail/get_base_iterator_buffer.hpp>
+#include <boost/compute/type_traits/is_device_iterator.hpp>
+#include <boost/compute/type_traits/result_of.hpp>
+
+namespace boost {
+namespace compute {
+
+// forward declaration for strided_iterator
+template<class Iterator>
+class strided_iterator;
+
+namespace detail {
+
+// helper class which defines the iterator_adaptor super-class
+// type for strided_iterator
+template<class Iterator>
+class strided_iterator_base
+{
+public:
+    typedef ::boost::iterator_adaptor<
+        ::boost::compute::strided_iterator<Iterator>,
+        Iterator,
+        typename std::iterator_traits<Iterator>::value_type,
+        typename std::iterator_traits<Iterator>::iterator_category
+    > type;
+};
+
+// helper class for including stride value in index expression
+template<class IndexExpr, class Stride>
+struct stride_expr
+{
+    stride_expr(const IndexExpr &expr, const Stride &stride)
+        : m_index_expr(expr),
+          m_stride(stride)
+    {
+    }
+
+    const IndexExpr m_index_expr;
+    const Stride m_stride;
+};
+
+template<class IndexExpr, class Stride>
+inline stride_expr<IndexExpr, Stride> make_stride_expr(const IndexExpr &expr,
+                                                       const Stride &stride)
+{
+    return stride_expr<IndexExpr, Stride>(expr, stride);
+}
+
+template<class IndexExpr, class Stride>
+inline meta_kernel& operator<<(meta_kernel &kernel,
+                               const stride_expr<IndexExpr, Stride> &expr)
+{
+    // (expr.m_stride * (expr.m_index_expr))
+    return kernel << "(" << static_cast<ulong_>(expr.m_stride)
+                  << " * (" << expr.m_index_expr << "))";
+}
+
+template<class Iterator, class Stride, class IndexExpr>
+struct strided_iterator_index_expr
+{
+    typedef typename std::iterator_traits<Iterator>::value_type result_type;
+
+    strided_iterator_index_expr(const Iterator &input_iter,
+                                const Stride &stride,
+                                const IndexExpr &index_expr)
+        : m_input_iter(input_iter),
+          m_stride(stride),
+          m_index_expr(index_expr)
+    {
+    }
+
+    const Iterator m_input_iter;
+    const Stride m_stride;
+    const IndexExpr m_index_expr;
+};
+
+template<class Iterator, class Stride, class IndexExpr>
+inline meta_kernel& operator<<(meta_kernel &kernel,
+                               const strided_iterator_index_expr<Iterator,
+                                                                 Stride,
+                                                                 IndexExpr> &expr)
+{
+    return kernel << expr.m_input_iter[make_stride_expr(expr.m_index_expr, expr.m_stride)];
+}
+
+} // end detail namespace
+
+/// \class strided_iterator
+/// \brief An iterator adaptor with adjustable iteration step.
+///
+/// The strided iterator adaptor skips over multiple elements each time
+/// it is incremented or decremented.
+///
+/// \see buffer_iterator, make_strided_iterator(), make_strided_iterator_end()
+template<class Iterator>
+class strided_iterator :
+    public detail::strided_iterator_base<Iterator>::type
+{
+public:
+    typedef typename
+        detail::strided_iterator_base<Iterator>::type super_type;
+    typedef typename super_type::value_type value_type;
+    typedef typename super_type::reference reference;
+    typedef typename super_type::base_type base_type;
+    typedef typename super_type::difference_type difference_type;
+
+    strided_iterator(Iterator iterator, difference_type stride)
+        : super_type(iterator),
+          m_stride(static_cast<difference_type>(stride))
+    {
+        // stride must be greater than zero
+        BOOST_ASSERT_MSG(stride > 0, "Stride must be greater than zero");
+    }
+
+    strided_iterator(const strided_iterator<Iterator> &other)
+        : super_type(other.base()),
+          m_stride(other.m_stride)
+    {
+    }
+
+    strided_iterator<Iterator>&
+    operator=(const strided_iterator<Iterator> &other)
+    {
+        if(this != &other){
+            super_type::operator=(other);
+
+            m_stride = other.m_stride;
+        }
+
+        return *this;
+    }
+
+    ~strided_iterator()
+    {
+    }
+
+    size_t get_index() const
+    {
+        return super_type::base().get_index();
+    }
+
+    const buffer& get_buffer() const
+    {
+        return detail::get_base_iterator_buffer(*this);
+    }
+
+    template<class IndexExpression>
+    detail::strided_iterator_index_expr<Iterator, difference_type, IndexExpression>
+    operator[](const IndexExpression &expr) const
+    {
+        typedef
+            typename detail::strided_iterator_index_expr<Iterator,
+                                                         difference_type,
+                                                         IndexExpression>
+            StridedIndexExprType;
+        return StridedIndexExprType(super_type::base(),m_stride, expr);
+    }
+
+private:
+    friend class ::boost::iterator_core_access;
+
+    reference dereference() const
+    {
+        return reference();
+    }
+
+    bool equal(const strided_iterator<Iterator> &other) const
+    {
+        return (other.m_stride == m_stride)
+                   && (other.base_reference() == this->base_reference());
+    }
+
+    void increment()
+    {
+        std::advance(super_type::base_reference(), m_stride);
+    }
+
+    void decrement()
+    {
+        std::advance(super_type::base_reference(),-m_stride);
+    }
+
+    void advance(typename super_type::difference_type n)
+    {
+        std::advance(super_type::base_reference(), n * m_stride);
+    }
+
+    difference_type distance_to(const strided_iterator<Iterator> &other) const
+    {
+        return std::distance(this->base_reference(), other.base_reference()) / m_stride;
+    }
+
+private:
+    difference_type m_stride;
+};
+
+/// Returns a strided_iterator for \p iterator with \p stride.
+///
+/// \param iterator the underlying iterator
+/// \param stride the iteration step for strided_iterator
+///
+/// \return a \c strided_iterator for \p iterator with \p stride.
+///
+/// For example, to create an iterator which iterates over every other
+/// element in a \c vector<int>:
+/// \code
+/// auto strided_iterator = make_strided_iterator(vec.begin(), 2);
+/// \endcode
+template<class Iterator>
+inline strided_iterator<Iterator>
+make_strided_iterator(Iterator iterator,
+                      typename std::iterator_traits<Iterator>::difference_type stride)
+{
+    return strided_iterator<Iterator>(iterator, stride);
+}
+
+/// Returns a strided_iterator which refers to element that would follow
+/// the last element accessible through strided_iterator for \p first iterator
+/// with \p stride.
+///
+/// Parameter \p stride must be greater than zero.
+///
+/// \param first the iterator referring to the first element accessible
+///        through strided_iterator for \p first with \p stride
+/// \param last the iterator referring to the last element that may be
+////       accessible through strided_iterator for \p first with \p stride
+/// \param stride the iteration step
+///
+/// \return a \c strided_iterator referring to element that would follow
+///         the last element accessible through strided_iterator for \p first
+///         iterator with \p stride.
+///
+/// It can be helpful when iterating over strided_iterator:
+/// \code
+/// // vec.size() may not be divisible by 3
+/// auto strided_iterator_begin = make_strided_iterator(vec.begin(), 3);
+/// auto strided_iterator_end = make_strided_iterator_end(vec.begin(), vec.end(), 3);
+///
+/// // copy every 3rd element to result
+/// boost::compute::copy(
+///         strided_iterator_begin,
+///         strided_iterator_end,
+///         result.begin(),
+///         queue
+/// );
+/// \endcode
+template<class Iterator>
+strided_iterator<Iterator>
+make_strided_iterator_end(Iterator first,
+                          Iterator last,
+                          typename std::iterator_traits<Iterator>::difference_type stride)
+{
+    typedef typename std::iterator_traits<Iterator>::difference_type difference_type;
+
+    // calculate distance from end to the last element that would be
+    // accessible through strided_iterator.
+    difference_type range = std::distance(first, last);
+    difference_type d = (range - 1) / stride;
+    d *= stride;
+    d -= range;
+    // advance from end to the element that would follow the last
+    // accessible element
+    Iterator end_for_strided_iterator = last;
+    std::advance(end_for_strided_iterator, d + stride);
+    return strided_iterator<Iterator>(end_for_strided_iterator, stride);
+}
+
+/// \internal_ (is_device_iterator specialization for strided_iterator)
+template<class Iterator>
+struct is_device_iterator<strided_iterator<Iterator> > : boost::true_type {};
+
+} // end compute namespace
+} // end boost namespace
+
+#endif // BOOST_COMPUTE_ITERATOR_STRIDED_ITERATOR_HPP