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    No license under any patent, copyright, trade secret or other
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    disclosure or delivery of the Materials, either expressly, by
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    intellectual property rights must be express and approved by Intel in
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*/

#ifndef __TBB_parallel_reduce_H
#define __TBB_parallel_reduce_H

#include <new>
#include "task.h"
#include "aligned_space.h"
#include "partitioner.h"
#include "tbb_profiling.h"

namespace tbb {

namespace interface9 {
//! @cond INTERNAL
namespace internal {

    using namespace tbb::internal;

    /** Values for reduction_context. */
    enum {
        root_task, left_child, right_child
    };

    /** Represented as a char, not enum, for compactness. */
    typedef char reduction_context;

    //! Task type used to combine the partial results of parallel_reduce.
    /** @ingroup algorithms */
    template<typename Body>
    class finish_reduce: public flag_task {
        //! Pointer to body, or NULL if the left child has not yet finished.
        bool has_right_zombie;
        const reduction_context my_context;
        Body* my_body;
        aligned_space<Body> zombie_space;
        finish_reduce( reduction_context context_ ) :
            has_right_zombie(false), // TODO: substitute by flag_task::child_stolen?
            my_context(context_),
            my_body(NULL)
        {
        }
        ~finish_reduce() {
            if( has_right_zombie )
                zombie_space.begin()->~Body();
        }
        task* execute() __TBB_override {
            if( has_right_zombie ) {
                // Right child was stolen.
                Body* s = zombie_space.begin();
                my_body->join( *s );
                // Body::join() won't be called if canceled. Defer destruction to destructor
            }
            if( my_context==left_child )
                itt_store_word_with_release( static_cast<finish_reduce*>(parent())->my_body, my_body );
            return NULL;
        }
        template<typename Range,typename Body_, typename Partitioner>
        friend class start_reduce;
    };

    //! allocate right task with new parent
    void allocate_sibling(task* start_reduce_task, task *tasks[], size_t start_bytes, size_t finish_bytes);

    //! Task type used to split the work of parallel_reduce.
    /** @ingroup algorithms */
    template<typename Range, typename Body, typename Partitioner>
    class start_reduce: public task {
        typedef finish_reduce<Body> finish_type;
        Body* my_body;
        Range my_range;
        typename Partitioner::task_partition_type my_partition;
        reduction_context my_context;
        task* execute() __TBB_override;
        //! Update affinity info, if any
        void note_affinity( affinity_id id ) __TBB_override {
            my_partition.note_affinity( id );
        }
        template<typename Body_>
        friend class finish_reduce;

public:
        //! Constructor used for root task
        start_reduce( const Range& range, Body* body, Partitioner& partitioner ) :
            my_body(body),
            my_range(range),
            my_partition(partitioner),
            my_context(root_task)
        {
        }
        //! Splitting constructor used to generate children.
        /** parent_ becomes left child.  Newly constructed object is right child. */
        start_reduce( start_reduce& parent_, typename Partitioner::split_type& split_obj ) :
            my_body(parent_.my_body),
            my_range(parent_.my_range, split_obj),
            my_partition(parent_.my_partition, split_obj),
            my_context(right_child)
        {
            my_partition.set_affinity(*this);
            parent_.my_context = left_child;
        }
        //! Construct right child from the given range as response to the demand.
        /** parent_ remains left child.  Newly constructed object is right child. */
        start_reduce( start_reduce& parent_, const Range& r, depth_t d ) :
            my_body(parent_.my_body),
            my_range(r),
            my_partition(parent_.my_partition, split()),
            my_context(right_child)
        {
            my_partition.set_affinity(*this);
            my_partition.align_depth( d ); // TODO: move into constructor of partitioner
            parent_.my_context = left_child;
        }
        static void run( const Range& range, Body& body, Partitioner& partitioner ) {
            if( !range.empty() ) {
#if !__TBB_TASK_GROUP_CONTEXT || TBB_JOIN_OUTER_TASK_GROUP
                task::spawn_root_and_wait( *new(task::allocate_root()) start_reduce(range,&body,partitioner) );
#else
                // Bound context prevents exceptions from body to affect nesting or sibling algorithms,
                // and allows users to handle exceptions safely by wrapping parallel_for in the try-block.
                task_group_context context(PARALLEL_REDUCE);
                task::spawn_root_and_wait( *new(task::allocate_root(context)) start_reduce(range,&body,partitioner) );
#endif /* __TBB_TASK_GROUP_CONTEXT && !TBB_JOIN_OUTER_TASK_GROUP */
            }
        }
#if __TBB_TASK_GROUP_CONTEXT
        static void run( const Range& range, Body& body, Partitioner& partitioner, task_group_context& context ) {
            if( !range.empty() )
                task::spawn_root_and_wait( *new(task::allocate_root(context)) start_reduce(range,&body,partitioner) );
        }
#endif /* __TBB_TASK_GROUP_CONTEXT */
        //! Run body for range
        void run_body( Range &r ) { (*my_body)( r ); }

        //! spawn right task, serves as callback for partitioner
        // TODO: remove code duplication from 'offer_work' methods
        void offer_work(typename Partitioner::split_type& split_obj) {
            task *tasks[2];
            allocate_sibling(static_cast<task*>(this), tasks, sizeof(start_reduce), sizeof(finish_type));
            new((void*)tasks[0]) finish_type(my_context);
            new((void*)tasks[1]) start_reduce(*this, split_obj);
            spawn(*tasks[1]);
        }
        //! spawn right task, serves as callback for partitioner
        void offer_work(const Range& r, depth_t d = 0) {
            task *tasks[2];
            allocate_sibling(static_cast<task*>(this), tasks, sizeof(start_reduce), sizeof(finish_type));
            new((void*)tasks[0]) finish_type(my_context);
            new((void*)tasks[1]) start_reduce(*this, r, d);
            spawn(*tasks[1]);
        }
    };

    //! allocate right task with new parent
    // TODO: 'inline' here is to avoid multiple definition error but for sake of code size this should not be inlined
    inline void allocate_sibling(task* start_reduce_task, task *tasks[], size_t start_bytes, size_t finish_bytes) {
        tasks[0] = &start_reduce_task->allocate_continuation().allocate(finish_bytes);
        start_reduce_task->set_parent(tasks[0]);
        tasks[0]->set_ref_count(2);
        tasks[1] = &tasks[0]->allocate_child().allocate(start_bytes);
    }

    template<typename Range, typename Body, typename Partitioner>
    task* start_reduce<Range,Body,Partitioner>::execute() {
        my_partition.check_being_stolen( *this );
        if( my_context==right_child ) {
            finish_type* parent_ptr = static_cast<finish_type*>(parent());
            if( !itt_load_word_with_acquire(parent_ptr->my_body) ) { // TODO: replace by is_stolen_task() or by parent_ptr->ref_count() == 2???
                my_body = new( parent_ptr->zombie_space.begin() ) Body(*my_body,split());
                parent_ptr->has_right_zombie = true;
            }
        } else __TBB_ASSERT(my_context==root_task,NULL);// because left leaf spawns right leafs without recycling
        my_partition.execute(*this, my_range);
        if( my_context==left_child ) {
            finish_type* parent_ptr = static_cast<finish_type*>(parent());
            __TBB_ASSERT(my_body!=parent_ptr->zombie_space.begin(),NULL);
            itt_store_word_with_release(parent_ptr->my_body, my_body );
        }
        return NULL;
    }

    //! Task type used to combine the partial results of parallel_deterministic_reduce.
    /** @ingroup algorithms */
    template<typename Body>
    class finish_deterministic_reduce: public task {
        Body &my_left_body;
        Body my_right_body;

        finish_deterministic_reduce( Body &body ) :
            my_left_body( body ),
            my_right_body( body, split() )
        {
        }
        task* execute() __TBB_override {
            my_left_body.join( my_right_body );
            return NULL;
        }
        template<typename Range,typename Body_, typename Partitioner>
        friend class start_deterministic_reduce;
    };

    //! Task type used to split the work of parallel_deterministic_reduce.
    /** @ingroup algorithms */
    template<typename Range, typename Body, typename Partitioner>
    class start_deterministic_reduce: public task {
        typedef finish_deterministic_reduce<Body> finish_type;
        Body &my_body;
        Range my_range;
        typename Partitioner::task_partition_type my_partition;
        task* execute() __TBB_override;

        //! Constructor used for root task
        start_deterministic_reduce( const Range& range, Body& body, Partitioner& partitioner ) :
            my_body( body ),
            my_range( range ),
            my_partition( partitioner )
        {
        }
        //! Splitting constructor used to generate children.
        /** parent_ becomes left child.  Newly constructed object is right child. */
        start_deterministic_reduce( start_deterministic_reduce& parent_, finish_type& c, typename Partitioner::split_type& split_obj ) :
            my_body( c.my_right_body ),
            my_range( parent_.my_range, split_obj ),
            my_partition( parent_.my_partition, split_obj )
        {
        }

public:
        static void run( const Range& range, Body& body, Partitioner& partitioner ) {
            if( !range.empty() ) {
#if !__TBB_TASK_GROUP_CONTEXT || TBB_JOIN_OUTER_TASK_GROUP
                task::spawn_root_and_wait( *new(task::allocate_root()) start_deterministic_reduce(range,&body,partitioner) );
#else
                // Bound context prevents exceptions from body to affect nesting or sibling algorithms,
                // and allows users to handle exceptions safely by wrapping parallel_for in the try-block.
                task_group_context context(PARALLEL_REDUCE);
                task::spawn_root_and_wait( *new(task::allocate_root(context)) start_deterministic_reduce(range,body,partitioner) );
#endif /* __TBB_TASK_GROUP_CONTEXT && !TBB_JOIN_OUTER_TASK_GROUP */
            }
        }
#if __TBB_TASK_GROUP_CONTEXT
        static void run( const Range& range, Body& body, Partitioner& partitioner, task_group_context& context ) {
            if( !range.empty() )
                task::spawn_root_and_wait( *new(task::allocate_root(context)) start_deterministic_reduce(range,body,partitioner) );
        }
#endif /* __TBB_TASK_GROUP_CONTEXT */

        void offer_work( typename Partitioner::split_type& split_obj) {
            task* tasks[2];
            allocate_sibling(static_cast<task*>(this), tasks, sizeof(start_deterministic_reduce), sizeof(finish_type));
            new((void*)tasks[0]) finish_type(my_body);
            new((void*)tasks[1]) start_deterministic_reduce(*this, *static_cast<finish_type*>(tasks[0]), split_obj);
            spawn(*tasks[1]);
        }

        void run_body( Range &r ) { my_body(r); }
    };

    template<typename Range, typename Body, typename Partitioner>
    task* start_deterministic_reduce<Range,Body, Partitioner>::execute() {
        my_partition.execute(*this, my_range);
        return NULL;
    }
} // namespace internal
//! @endcond
} //namespace interfaceX

//! @cond INTERNAL
namespace internal {
    using interface9::internal::start_reduce;
    using interface9::internal::start_deterministic_reduce;
    //! Auxiliary class for parallel_reduce; for internal use only.
    /** The adaptor class that implements \ref parallel_reduce_body_req "parallel_reduce Body"
        using given \ref parallel_reduce_lambda_req "anonymous function objects".
     **/
    /** @ingroup algorithms */
    template<typename Range, typename Value, typename RealBody, typename Reduction>
    class lambda_reduce_body {

//FIXME: decide if my_real_body, my_reduction, and identity_element should be copied or referenced
//       (might require some performance measurements)

        const Value&     identity_element;
        const RealBody&  my_real_body;
        const Reduction& my_reduction;
        Value            my_value;
        lambda_reduce_body& operator= ( const lambda_reduce_body& other );
    public:
        lambda_reduce_body( const Value& identity, const RealBody& body, const Reduction& reduction )
            : identity_element(identity)
            , my_real_body(body)
            , my_reduction(reduction)
            , my_value(identity)
        { }
        lambda_reduce_body( const lambda_reduce_body& other )
            : identity_element(other.identity_element)
            , my_real_body(other.my_real_body)
            , my_reduction(other.my_reduction)
            , my_value(other.my_value)
        { }
        lambda_reduce_body( lambda_reduce_body& other, tbb::split )
            : identity_element(other.identity_element)
            , my_real_body(other.my_real_body)
            , my_reduction(other.my_reduction)
            , my_value(other.identity_element)
        { }
        void operator()(Range& range) {
            my_value = my_real_body(range, const_cast<const Value&>(my_value));
        }
        void join( lambda_reduce_body& rhs ) {
            my_value = my_reduction(const_cast<const Value&>(my_value), const_cast<const Value&>(rhs.my_value));
        }
        Value result() const {
            return my_value;
        }
    };

} // namespace internal
//! @endcond

// Requirements on Range concept are documented in blocked_range.h

/** \page parallel_reduce_body_req Requirements on parallel_reduce body
    Class \c Body implementing the concept of parallel_reduce body must define:
    - \code Body::Body( Body&, split ); \endcode        Splitting constructor.
                                                        Must be able to run concurrently with operator() and method \c join
    - \code Body::~Body(); \endcode                     Destructor
    - \code void Body::operator()( Range& r ); \endcode Function call operator applying body to range \c r
                                                        and accumulating the result
    - \code void Body::join( Body& b ); \endcode        Join results.
                                                        The result in \c b should be merged into the result of \c this
**/

/** \page parallel_reduce_lambda_req Requirements on parallel_reduce anonymous function objects (lambda functions)
    TO BE DOCUMENTED
**/

/** \name parallel_reduce
    See also requirements on \ref range_req "Range" and \ref parallel_reduce_body_req "parallel_reduce Body". **/
//@{

//! Parallel iteration with reduction and default partitioner.
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_reduce( const Range& range, Body& body ) {
    internal::start_reduce<Range,Body, const __TBB_DEFAULT_PARTITIONER>::run( range, body, __TBB_DEFAULT_PARTITIONER() );
}

//! Parallel iteration with reduction and simple_partitioner
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_reduce( const Range& range, Body& body, const simple_partitioner& partitioner ) {
    internal::start_reduce<Range,Body,const simple_partitioner>::run( range, body, partitioner );
}

//! Parallel iteration with reduction and auto_partitioner
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_reduce( const Range& range, Body& body, const auto_partitioner& partitioner ) {
    internal::start_reduce<Range,Body,const auto_partitioner>::run( range, body, partitioner );
}

//! Parallel iteration with reduction and static_partitioner
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_reduce( const Range& range, Body& body, const static_partitioner& partitioner ) {
    internal::start_reduce<Range,Body,const static_partitioner>::run( range, body, partitioner );
}

//! Parallel iteration with reduction and affinity_partitioner
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_reduce( const Range& range, Body& body, affinity_partitioner& partitioner ) {
    internal::start_reduce<Range,Body,affinity_partitioner>::run( range, body, partitioner );
}

#if __TBB_TASK_GROUP_CONTEXT
//! Parallel iteration with reduction, simple partitioner and user-supplied context.
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_reduce( const Range& range, Body& body, const simple_partitioner& partitioner, task_group_context& context ) {
    internal::start_reduce<Range,Body,const simple_partitioner>::run( range, body, partitioner, context );
}

//! Parallel iteration with reduction, auto_partitioner and user-supplied context
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_reduce( const Range& range, Body& body, const auto_partitioner& partitioner, task_group_context& context ) {
    internal::start_reduce<Range,Body,const auto_partitioner>::run( range, body, partitioner, context );
}

//! Parallel iteration with reduction, static_partitioner and user-supplied context
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_reduce( const Range& range, Body& body, const static_partitioner& partitioner, task_group_context& context ) {
    internal::start_reduce<Range,Body,const static_partitioner>::run( range, body, partitioner, context );
}

//! Parallel iteration with reduction, affinity_partitioner and user-supplied context
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_reduce( const Range& range, Body& body, affinity_partitioner& partitioner, task_group_context& context ) {
    internal::start_reduce<Range,Body,affinity_partitioner>::run( range, body, partitioner, context );
}
#endif /* __TBB_TASK_GROUP_CONTEXT */

/** parallel_reduce overloads that work with anonymous function objects
    (see also \ref parallel_reduce_lambda_req "requirements on parallel_reduce anonymous function objects"). **/

//! Parallel iteration with reduction and default partitioner.
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction ) {
    internal::lambda_reduce_body<Range,Value,RealBody,Reduction> body(identity, real_body, reduction);
    internal::start_reduce<Range,internal::lambda_reduce_body<Range,Value,RealBody,Reduction>,const __TBB_DEFAULT_PARTITIONER>
                          ::run(range, body, __TBB_DEFAULT_PARTITIONER() );
    return body.result();
}

//! Parallel iteration with reduction and simple_partitioner.
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction,
                       const simple_partitioner& partitioner ) {
    internal::lambda_reduce_body<Range,Value,RealBody,Reduction> body(identity, real_body, reduction);
    internal::start_reduce<Range,internal::lambda_reduce_body<Range,Value,RealBody,Reduction>,const simple_partitioner>
                          ::run(range, body, partitioner );
    return body.result();
}

//! Parallel iteration with reduction and auto_partitioner
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction,
                       const auto_partitioner& partitioner ) {
    internal::lambda_reduce_body<Range,Value,RealBody,Reduction> body(identity, real_body, reduction);
    internal::start_reduce<Range,internal::lambda_reduce_body<Range,Value,RealBody,Reduction>,const auto_partitioner>
                          ::run( range, body, partitioner );
    return body.result();
}

//! Parallel iteration with reduction and static_partitioner
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction,
                       const static_partitioner& partitioner ) {
    internal::lambda_reduce_body<Range,Value,RealBody,Reduction> body(identity, real_body, reduction);
    internal::start_reduce<Range,internal::lambda_reduce_body<Range,Value,RealBody,Reduction>,const static_partitioner>
                                        ::run( range, body, partitioner );
    return body.result();
}

//! Parallel iteration with reduction and affinity_partitioner
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction,
                       affinity_partitioner& partitioner ) {
    internal::lambda_reduce_body<Range,Value,RealBody,Reduction> body(identity, real_body, reduction);
    internal::start_reduce<Range,internal::lambda_reduce_body<Range,Value,RealBody,Reduction>,affinity_partitioner>
                                        ::run( range, body, partitioner );
    return body.result();
}

#if __TBB_TASK_GROUP_CONTEXT
//! Parallel iteration with reduction, simple partitioner and user-supplied context.
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction,
                       const simple_partitioner& partitioner, task_group_context& context ) {
    internal::lambda_reduce_body<Range,Value,RealBody,Reduction> body(identity, real_body, reduction);
    internal::start_reduce<Range,internal::lambda_reduce_body<Range,Value,RealBody,Reduction>,const simple_partitioner>
                          ::run( range, body, partitioner, context );
    return body.result();
}

//! Parallel iteration with reduction, auto_partitioner and user-supplied context
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction,
                       const auto_partitioner& partitioner, task_group_context& context ) {
    internal::lambda_reduce_body<Range,Value,RealBody,Reduction> body(identity, real_body, reduction);
    internal::start_reduce<Range,internal::lambda_reduce_body<Range,Value,RealBody,Reduction>,const auto_partitioner>
                          ::run( range, body, partitioner, context );
    return body.result();
}

//! Parallel iteration with reduction, static_partitioner and user-supplied context
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction,
                       const static_partitioner& partitioner, task_group_context& context ) {
    internal::lambda_reduce_body<Range,Value,RealBody,Reduction> body(identity, real_body, reduction);
    internal::start_reduce<Range,internal::lambda_reduce_body<Range,Value,RealBody,Reduction>,const static_partitioner>
                                        ::run( range, body, partitioner, context );
    return body.result();
}

//! Parallel iteration with reduction, affinity_partitioner and user-supplied context
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction,
                       affinity_partitioner& partitioner, task_group_context& context ) {
    internal::lambda_reduce_body<Range,Value,RealBody,Reduction> body(identity, real_body, reduction);
    internal::start_reduce<Range,internal::lambda_reduce_body<Range,Value,RealBody,Reduction>,affinity_partitioner>
                                        ::run( range, body, partitioner, context );
    return body.result();
}
#endif /* __TBB_TASK_GROUP_CONTEXT */

//! Parallel iteration with deterministic reduction and default simple partitioner.
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_deterministic_reduce( const Range& range, Body& body ) {
    internal::start_deterministic_reduce<Range, Body, const simple_partitioner>::run(range, body, simple_partitioner());
}

//! Parallel iteration with deterministic reduction and simple partitioner.
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_deterministic_reduce( const Range& range, Body& body, const simple_partitioner& partitioner ) {
    internal::start_deterministic_reduce<Range, Body, const simple_partitioner>::run(range, body, partitioner);
}

//! Parallel iteration with deterministic reduction and static partitioner.
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_deterministic_reduce( const Range& range, Body& body, const static_partitioner& partitioner ) {
    internal::start_deterministic_reduce<Range, Body, const static_partitioner>::run(range, body, partitioner);
}

#if __TBB_TASK_GROUP_CONTEXT
//! Parallel iteration with deterministic reduction, default simple partitioner and user-supplied context.
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_deterministic_reduce( const Range& range, Body& body, task_group_context& context ) {
    internal::start_deterministic_reduce<Range,Body, const simple_partitioner>::run( range, body, simple_partitioner(), context );
}

//! Parallel iteration with deterministic reduction, simple partitioner and user-supplied context.
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_deterministic_reduce( const Range& range, Body& body, const simple_partitioner& partitioner, task_group_context& context ) {
    internal::start_deterministic_reduce<Range, Body, const simple_partitioner>::run(range, body, partitioner, context);
}

//! Parallel iteration with deterministic reduction, static partitioner and user-supplied context.
/** @ingroup algorithms **/
template<typename Range, typename Body>
void parallel_deterministic_reduce( const Range& range, Body& body, const static_partitioner& partitioner, task_group_context& context ) {
    internal::start_deterministic_reduce<Range, Body, const static_partitioner>::run(range, body, partitioner, context);
}
#endif /* __TBB_TASK_GROUP_CONTEXT */

/** parallel_reduce overloads that work with anonymous function objects
    (see also \ref parallel_reduce_lambda_req "requirements on parallel_reduce anonymous function objects"). **/

//! Parallel iteration with deterministic reduction and default simple partitioner.
// TODO: consider making static_partitioner the default
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_deterministic_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction ) {
    return parallel_deterministic_reduce(range, identity, real_body, reduction, simple_partitioner());
}

//! Parallel iteration with deterministic reduction and simple partitioner.
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_deterministic_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction, const simple_partitioner& partitioner ) {
    internal::lambda_reduce_body<Range,Value,RealBody,Reduction> body(identity, real_body, reduction);
    internal::start_deterministic_reduce<Range,internal::lambda_reduce_body<Range,Value,RealBody,Reduction>, const simple_partitioner>
                          ::run(range, body, partitioner);
    return body.result();
}

//! Parallel iteration with deterministic reduction and static partitioner.
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_deterministic_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction, const static_partitioner& partitioner ) {
    internal::lambda_reduce_body<Range, Value, RealBody, Reduction> body(identity, real_body, reduction);
    internal::start_deterministic_reduce<Range, internal::lambda_reduce_body<Range, Value, RealBody, Reduction>, const static_partitioner>
        ::run(range, body, partitioner);
    return body.result();
}
#if __TBB_TASK_GROUP_CONTEXT
//! Parallel iteration with deterministic reduction, default simple partitioner and user-supplied context.
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_deterministic_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction,
    task_group_context& context ) {
    return parallel_deterministic_reduce(range, identity, real_body, reduction, simple_partitioner(), context);
}

//! Parallel iteration with deterministic reduction, simple partitioner and user-supplied context.
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_deterministic_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction,
    const simple_partitioner& partitioner, task_group_context& context ) {
    internal::lambda_reduce_body<Range, Value, RealBody, Reduction> body(identity, real_body, reduction);
    internal::start_deterministic_reduce<Range, internal::lambda_reduce_body<Range, Value, RealBody, Reduction>, const simple_partitioner>
        ::run(range, body, partitioner, context);
    return body.result();
}

//! Parallel iteration with deterministic reduction, static partitioner and user-supplied context.
/** @ingroup algorithms **/
template<typename Range, typename Value, typename RealBody, typename Reduction>
Value parallel_deterministic_reduce( const Range& range, const Value& identity, const RealBody& real_body, const Reduction& reduction,
    const static_partitioner& partitioner, task_group_context& context ) {
    internal::lambda_reduce_body<Range, Value, RealBody, Reduction> body(identity, real_body, reduction);
    internal::start_deterministic_reduce<Range, internal::lambda_reduce_body<Range, Value, RealBody, Reduction>, const static_partitioner>
        ::run(range, body, partitioner, context);
    return body.result();
}
#endif /* __TBB_TASK_GROUP_CONTEXT */
//@}

} // namespace tbb

#endif /* __TBB_parallel_reduce_H */
