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| |
| #ifndef QTCONCURRENT_MAPKERNEL_H |
| #define QTCONCURRENT_MAPKERNEL_H |
| |
| #include <QtConcurrent/qtconcurrent_global.h> |
| |
| #if !defined(QT_NO_CONCURRENT) || defined (Q_CLANG_QDOC) |
| |
| #include <QtConcurrent/qtconcurrentiteratekernel.h> |
| #include <QtConcurrent/qtconcurrentreducekernel.h> |
| |
| QT_BEGIN_NAMESPACE |
| |
| |
| namespace QtConcurrent { |
| |
| // map kernel, works with both parallel-for and parallel-while |
| template <typename Iterator, typename MapFunctor> |
| class MapKernel : public IterateKernel<Iterator, void> |
| { |
| MapFunctor map; |
| public: |
| typedef void ReturnType; |
| MapKernel(Iterator begin, Iterator end, MapFunctor _map) |
| : IterateKernel<Iterator, void>(begin, end), map(_map) |
| { } |
| |
| bool runIteration(Iterator it, int, void *) override |
| { |
| map(*it); |
| return false; |
| } |
| |
| bool runIterations(Iterator sequenceBeginIterator, int beginIndex, int endIndex, void *) override |
| { |
| Iterator it = sequenceBeginIterator; |
| std::advance(it, beginIndex); |
| for (int i = beginIndex; i < endIndex; ++i) { |
| runIteration(it, i, nullptr); |
| std::advance(it, 1); |
| } |
| |
| return false; |
| } |
| }; |
| |
| template <typename ReducedResultType, |
| typename Iterator, |
| typename MapFunctor, |
| typename ReduceFunctor, |
| typename Reducer = ReduceKernel<ReduceFunctor, |
| ReducedResultType, |
| typename MapFunctor::result_type> > |
| class MappedReducedKernel : public IterateKernel<Iterator, ReducedResultType> |
| { |
| ReducedResultType reducedResult; |
| MapFunctor map; |
| ReduceFunctor reduce; |
| Reducer reducer; |
| public: |
| typedef ReducedResultType ReturnType; |
| MappedReducedKernel(Iterator begin, Iterator end, MapFunctor _map, ReduceFunctor _reduce, ReduceOptions reduceOptions) |
| : IterateKernel<Iterator, ReducedResultType>(begin, end), reducedResult(), map(_map), reduce(_reduce), reducer(reduceOptions) |
| { } |
| |
| MappedReducedKernel(ReducedResultType initialValue, |
| MapFunctor _map, |
| ReduceFunctor _reduce) |
| : reducedResult(initialValue), map(_map), reduce(_reduce) |
| { } |
| |
| bool runIteration(Iterator it, int index, ReducedResultType *) override |
| { |
| IntermediateResults<typename MapFunctor::result_type> results; |
| results.begin = index; |
| results.end = index + 1; |
| |
| results.vector.append(map(*it)); |
| reducer.runReduce(reduce, reducedResult, results); |
| return false; |
| } |
| |
| bool runIterations(Iterator sequenceBeginIterator, int beginIndex, int endIndex, ReducedResultType *) override |
| { |
| IntermediateResults<typename MapFunctor::result_type> results; |
| results.begin = beginIndex; |
| results.end = endIndex; |
| results.vector.reserve(endIndex - beginIndex); |
| |
| Iterator it = sequenceBeginIterator; |
| std::advance(it, beginIndex); |
| for (int i = beginIndex; i < endIndex; ++i) { |
| results.vector.append(map(*(it))); |
| std::advance(it, 1); |
| } |
| |
| reducer.runReduce(reduce, reducedResult, results); |
| return false; |
| } |
| |
| void finish() override |
| { |
| reducer.finish(reduce, reducedResult); |
| } |
| |
| bool shouldThrottleThread() override |
| { |
| return IterateKernel<Iterator, ReducedResultType>::shouldThrottleThread() || reducer.shouldThrottle(); |
| } |
| |
| bool shouldStartThread() override |
| { |
| return IterateKernel<Iterator, ReducedResultType>::shouldStartThread() && reducer.shouldStartThread(); |
| } |
| |
| typedef ReducedResultType ResultType; |
| ReducedResultType *result() override |
| { |
| return &reducedResult; |
| } |
| }; |
| |
| template <typename Iterator, typename MapFunctor> |
| class MappedEachKernel : public IterateKernel<Iterator, typename MapFunctor::result_type> |
| { |
| MapFunctor map; |
| typedef typename MapFunctor::result_type T; |
| public: |
| typedef T ReturnType; |
| typedef T ResultType; |
| |
| MappedEachKernel(Iterator begin, Iterator end, MapFunctor _map) |
| : IterateKernel<Iterator, T>(begin, end), map(_map) { } |
| |
| bool runIteration(Iterator it, int, T *result) override |
| { |
| *result = map(*it); |
| return true; |
| } |
| |
| bool runIterations(Iterator sequenceBeginIterator, int beginIndex, int endIndex, T *results) override |
| { |
| |
| Iterator it = sequenceBeginIterator; |
| std::advance(it, beginIndex); |
| for (int i = beginIndex; i < endIndex; ++i) { |
| runIteration(it, i, results + (i - beginIndex)); |
| std::advance(it, 1); |
| } |
| |
| return true; |
| } |
| }; |
| |
| //! [qtconcurrentmapkernel-1] |
| template <typename Iterator, typename Functor> |
| inline ThreadEngineStarter<void> startMap(Iterator begin, Iterator end, Functor functor) |
| { |
| return startThreadEngine(new MapKernel<Iterator, Functor>(begin, end, functor)); |
| } |
| |
| //! [qtconcurrentmapkernel-2] |
| template <typename T, typename Iterator, typename Functor> |
| inline ThreadEngineStarter<T> startMapped(Iterator begin, Iterator end, Functor functor) |
| { |
| return startThreadEngine(new MappedEachKernel<Iterator, Functor>(begin, end, functor)); |
| } |
| |
| /* |
| The SequnceHolder class is used to hold a reference to the |
| sequence we are working on. |
| */ |
| template <typename Sequence, typename Base, typename Functor> |
| struct SequenceHolder1 : public Base |
| { |
| SequenceHolder1(const Sequence &_sequence, Functor functor) |
| : Base(_sequence.begin(), _sequence.end(), functor), sequence(_sequence) |
| { } |
| |
| Sequence sequence; |
| |
| void finish() override |
| { |
| Base::finish(); |
| // Clear the sequence to make sure all temporaries are destroyed |
| // before finished is signaled. |
| sequence = Sequence(); |
| } |
| }; |
| |
| //! [qtconcurrentmapkernel-3] |
| template <typename T, typename Sequence, typename Functor> |
| inline ThreadEngineStarter<T> startMapped(const Sequence &sequence, Functor functor) |
| { |
| typedef SequenceHolder1<Sequence, |
| MappedEachKernel<typename Sequence::const_iterator , Functor>, Functor> |
| SequenceHolderType; |
| |
| return startThreadEngine(new SequenceHolderType(sequence, functor)); |
| } |
| |
| //! [qtconcurrentmapkernel-4] |
| template <typename IntermediateType, typename ResultType, typename Sequence, typename MapFunctor, typename ReduceFunctor> |
| inline ThreadEngineStarter<ResultType> startMappedReduced(const Sequence & sequence, |
| MapFunctor mapFunctor, ReduceFunctor reduceFunctor, |
| ReduceOptions options) |
| { |
| typedef typename Sequence::const_iterator Iterator; |
| typedef ReduceKernel<ReduceFunctor, ResultType, IntermediateType> Reducer; |
| typedef MappedReducedKernel<ResultType, Iterator, MapFunctor, ReduceFunctor, Reducer> MappedReduceType; |
| typedef SequenceHolder2<Sequence, MappedReduceType, MapFunctor, ReduceFunctor> SequenceHolderType; |
| return startThreadEngine(new SequenceHolderType(sequence, mapFunctor, reduceFunctor, options)); |
| } |
| |
| //! [qtconcurrentmapkernel-5] |
| template <typename IntermediateType, typename ResultType, typename Iterator, typename MapFunctor, typename ReduceFunctor> |
| inline ThreadEngineStarter<ResultType> startMappedReduced(Iterator begin, Iterator end, |
| MapFunctor mapFunctor, ReduceFunctor reduceFunctor, |
| ReduceOptions options) |
| { |
| typedef ReduceKernel<ReduceFunctor, ResultType, IntermediateType> Reducer; |
| typedef MappedReducedKernel<ResultType, Iterator, MapFunctor, ReduceFunctor, Reducer> MappedReduceType; |
| return startThreadEngine(new MappedReduceType(begin, end, mapFunctor, reduceFunctor, options)); |
| } |
| |
| } // namespace QtConcurrent |
| |
| |
| QT_END_NAMESPACE |
| |
| #endif // QT_NO_CONCURRENT |
| |
| #endif |