QtConcurrent::run: allow to select the thread pool on which to run the task

This is the second and last part of the forward-port of
https://qt.gitorious.org/qt/qt/merge_requests/1281

[ChangeLog][QtConcurrent] run() now optionally takes as its first argument
the QThreadPool to run the task on.

Task-number: QTBUG-17220
Change-Id: I4b46eca6ef7de9cd34dac07e6d4b8ad830426b97
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>

src/concurrent/doc/snippets/code/src_concurrent_qtconcurrentrun.cpp

@@ -44,6 +44,13 @@ QFuture<void> future = QtConcurrent::run(aFunction);
 //! [0]
 
 
+//! [explicit-pool-0]
+extern void aFunction();
+QThreadPool pool;
+QFuture<void> future = QtConcurrent::run(&pool, aFunction);
+//! [explicit-pool-0]
+
+
 //! [1]
 extern void aFunctionWithArguments(int arg1, double arg2, const QString &string);
 

src/concurrent/qtconcurrentrun.cpp

@@ -59,6 +59,11 @@
     QThreadPool. You can use the QFuture and QFutureWatcher classes to monitor
     the status of the function.
 
+    To use a dedicated thread pool, you can pass the QThreadPool as
+    the first argument:
+
+    \snippet code/src_concurrent_qtconcurrentrun.cpp explicit-pool-0
+
     \section1 Passing Arguments to the Function
 
     Passing arguments to the function is done by adding them to the
@@ -130,9 +135,31 @@
 /*!
     \fn QFuture<T> QtConcurrent::run(Function function, ...);
 
+    Equivalent to
+    \code
+    QtConcurrent::run(QThreadPool::globalInstance(), function, ...);
+    \endcode
+
     Runs \a function in a separate thread. The thread is taken from the global
-    QThreadPool. Note that the function may not run immediately; the function
-    will only be run when a thread is available.
+    QThreadPool. Note that \a function may not run immediately; \a function
+    will only be run once a thread becomes available.
+
+    T is the same type as the return value of \a function. Non-void return
+    values can be accessed via the QFuture::result() function.
+
+    Note that the QFuture returned by QtConcurrent::run() does not support
+    canceling, pausing, or progress reporting. The QFuture returned can only
+    be used to query for the running/finished status and the return value of
+    the function.
+*/
+
+/*!
+    \since 5.4
+    \fn QFuture<T> QtConcurrent::run(QThreadPool *pool, Function function, ...);
+
+    Runs \a function in a separate thread. The thread is taken from the
+    QThreadPool \a pool. Note that \a function may not run immediately; \a function
+    will only be run once a thread becomes available.
 
     T is the same type as the return value of \a function. Non-void return
     values can be accessed via the QFuture::result() function.

src/concurrent/qtconcurrentrun.h

@@ -60,6 +60,9 @@ namespace QtConcurrent {
     template <typename T>
     QFuture<T> run(Function function, ...);
 
+    template <typename T>
+    QFuture<T> run(QThreadPool *pool, Function function, ...);
+
 } // namespace QtConcurrent
 
 #else
@@ -334,6 +337,277 @@ QFuture<T> run(const Class *object, T (Class::*fn)(Param1, Param2, Param3, Param
     return (new typename SelectStoredConstMemberFunctionPointerCall5<T, Class, Param1, Arg1, Param2, Arg2, Param3, Arg3, Param4, Arg4, Param5, Arg5>::type(fn, object, arg1, arg2, arg3, arg4, arg5))->start();
 }
 
+// ...and the same with a QThreadPool *pool argument...
+// generate from the above by c'n'p and s/run(/run(QThreadPool *pool, / and s/start()/start(pool)/
+
+template <typename T>
+QFuture<T> run(QThreadPool *pool, T (*functionPointer)())
+{
+    return (new StoredFunctorCall0<T, T (*)()>(functionPointer))->start(pool);
+}
+template <typename T, typename Param1, typename Arg1>
+QFuture<T> run(QThreadPool *pool, T (*functionPointer)(Param1), const Arg1 &arg1)
+{
+    return (new StoredFunctorCall1<T, T (*)(Param1), Arg1>(functionPointer, arg1))->start(pool);
+}
+template <typename T, typename Param1, typename Arg1, typename Param2, typename Arg2>
+QFuture<T> run(QThreadPool *pool, T (*functionPointer)(Param1, Param2), const Arg1 &arg1, const Arg2 &arg2)
+{
+    return (new StoredFunctorCall2<T, T (*)(Param1, Param2), Arg1, Arg2>(functionPointer, arg1, arg2))->start(pool);
+}
+template <typename T, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3>
+QFuture<T> run(QThreadPool *pool, T (*functionPointer)(Param1, Param2, Param3), const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3)
+{
+    return (new StoredFunctorCall3<T, T (*)(Param1, Param2, Param3), Arg1, Arg2, Arg3>(functionPointer, arg1, arg2, arg3))->start(pool);
+}
+template <typename T, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3, typename Param4, typename Arg4>
+QFuture<T> run(QThreadPool *pool, T (*functionPointer)(Param1, Param2, Param3, Param4), const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4)
+{
+    return (new StoredFunctorCall4<T, T (*)(Param1, Param2, Param3, Param4), Arg1, Arg2, Arg3, Arg4>(functionPointer, arg1, arg2, arg3, arg4))->start(pool);
+}
+template <typename T, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3, typename Param4, typename Arg4, typename Param5, typename Arg5>
+QFuture<T> run(QThreadPool *pool, T (*functionPointer)(Param1, Param2, Param3, Param4, Param5), const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4, const Arg5 &arg5)
+{
+    return (new StoredFunctorCall5<T, T (*)(Param1, Param2, Param3, Param4, Param5), Arg1, Arg2, Arg3, Arg4, Arg5>(functionPointer, arg1, arg2, arg3, arg4, arg5))->start(pool);
+}
+
+#if defined(Q_COMPILER_DECLTYPE) && defined(Q_COMPILER_AUTO_FUNCTION)
+
+template <typename Functor>
+auto run(QThreadPool *pool, Functor functor) -> typename QtPrivate::QEnableIf<!QtPrivate::HasResultType<Functor>::Value, QFuture<decltype(functor())> >::Type
+{
+    typedef decltype(functor()) result_type;
+    return (new StoredFunctorCall0<result_type, Functor>(functor))->start(pool);
+}
+
+template <typename Functor, typename Arg1>
+auto run(QThreadPool *pool, Functor functor, const Arg1 &arg1)
+    -> typename QtPrivate::QEnableIf<!QtPrivate::HasResultType<Functor>::Value, QFuture<decltype(functor(arg1))> >::Type
+{
+    typedef decltype(functor(arg1)) result_type;
+    return (new StoredFunctorCall1<result_type, Functor, Arg1>(functor, arg1))->start(pool);
+}
+
+template <typename Functor, typename Arg1, typename Arg2>
+auto run(QThreadPool *pool, Functor functor, const Arg1 &arg1, const Arg2 &arg2)
+    -> typename QtPrivate::QEnableIf<!QtPrivate::HasResultType<Functor>::Value, QFuture<decltype(functor(arg1, arg2))> >::Type
+{
+    typedef decltype(functor(arg1, arg2)) result_type;
+    return (new StoredFunctorCall2<result_type, Functor, Arg1, Arg2>(functor, arg1, arg2))->start(pool);
+}
+
+template <typename Functor, typename Arg1, typename Arg2, typename Arg3>
+auto run(QThreadPool *pool, Functor functor, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3)
+    -> typename QtPrivate::QEnableIf<!QtPrivate::HasResultType<Functor>::Value, QFuture<decltype(functor(arg1, arg2, arg3))> >::Type
+{
+    typedef decltype(functor(arg1, arg2, arg3)) result_type;
+    return (new StoredFunctorCall3<result_type, Functor, Arg1, Arg2, Arg3>(functor, arg1, arg2, arg3))->start(pool);
+}
+
+template <typename Functor, typename Arg1, typename Arg2, typename Arg3, typename Arg4>
+auto run(QThreadPool *pool, Functor functor, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4)
+    -> typename QtPrivate::QEnableIf<!QtPrivate::HasResultType<Functor>::Value, QFuture<decltype(functor(arg1, arg2, arg3, arg4))> >::Type
+{
+    typedef decltype(functor(arg1, arg2, arg3, arg4)) result_type;
+    return (new StoredFunctorCall4<result_type, Functor, Arg1, Arg2, Arg3, Arg4>(functor, arg1, arg2, arg3, arg4))->start(pool);
+}
+
+template <typename Functor, typename Arg1, typename Arg2, typename Arg3, typename Arg4, typename Arg5>
+auto run(QThreadPool *pool, Functor functor, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4, const Arg5 &arg5)
+    -> typename QtPrivate::QEnableIf<!QtPrivate::HasResultType<Functor>::Value, QFuture<decltype(functor(arg1, arg2, arg3, arg4, arg5))> >::Type
+{
+    typedef decltype(functor(arg1, arg2, arg3, arg4, arg5)) result_type;
+    return (new StoredFunctorCall5<result_type, Functor, Arg1, Arg2, Arg3, Arg4, Arg5>(functor, arg1, arg2, arg3, arg4, arg5))->start(pool);
+}
+
+#endif
+
+template <typename FunctionObject>
+QFuture<typename FunctionObject::result_type> run(QThreadPool *pool, FunctionObject functionObject)
+{
+    return (new StoredFunctorCall0<typename FunctionObject::result_type, FunctionObject>(functionObject))->start(pool);
+}
+template <typename FunctionObject, typename Arg1>
+QFuture<typename FunctionObject::result_type> run(QThreadPool *pool, FunctionObject functionObject, const Arg1 &arg1)
+{
+    return (new StoredFunctorCall1<typename FunctionObject::result_type, FunctionObject, Arg1>(functionObject, arg1))->start(pool);
+}
+template <typename FunctionObject, typename Arg1, typename Arg2>
+QFuture<typename FunctionObject::result_type> run(QThreadPool *pool, FunctionObject functionObject, const Arg1 &arg1, const Arg2 &arg2)
+{
+    return (new StoredFunctorCall2<typename FunctionObject::result_type, FunctionObject, Arg1, Arg2>(functionObject, arg1, arg2))->start(pool);
+}
+template <typename FunctionObject, typename Arg1, typename Arg2, typename Arg3>
+QFuture<typename FunctionObject::result_type> run(QThreadPool *pool, FunctionObject functionObject, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3)
+{
+    return (new StoredFunctorCall3<typename FunctionObject::result_type, FunctionObject, Arg1, Arg2, Arg3>(functionObject, arg1, arg2, arg3))->start(pool);
+}
+template <typename FunctionObject, typename Arg1, typename Arg2, typename Arg3, typename Arg4>
+QFuture<typename FunctionObject::result_type> run(QThreadPool *pool, FunctionObject functionObject, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4)
+{
+    return (new StoredFunctorCall4<typename FunctionObject::result_type, FunctionObject, Arg1, Arg2, Arg3, Arg4>(functionObject, arg1, arg2, arg3, arg4))->start(pool);
+}
+template <typename FunctionObject, typename Arg1, typename Arg2, typename Arg3, typename Arg4, typename Arg5>
+QFuture<typename FunctionObject::result_type> run(QThreadPool *pool, FunctionObject functionObject, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4, const Arg5 &arg5)
+{
+    return (new StoredFunctorCall5<typename FunctionObject::result_type, FunctionObject, Arg1, Arg2, Arg3, Arg4, Arg5>(functionObject, arg1, arg2, arg3, arg4, arg5))->start(pool);
+}
+
+template <typename FunctionObject>
+QFuture<typename FunctionObject::result_type> run(QThreadPool *pool, FunctionObject *functionObject)
+{
+    return (new typename SelectStoredFunctorPointerCall0<typename FunctionObject::result_type, FunctionObject>::type(functionObject))->start(pool);
+}
+template <typename FunctionObject, typename Arg1>
+QFuture<typename FunctionObject::result_type> run(QThreadPool *pool, FunctionObject *functionObject, const Arg1 &arg1)
+{
+    return (new typename SelectStoredFunctorPointerCall1<typename FunctionObject::result_type, FunctionObject, Arg1>::type(functionObject, arg1))->start(pool);
+}
+template <typename FunctionObject, typename Arg1, typename Arg2>
+QFuture<typename FunctionObject::result_type> run(QThreadPool *pool, FunctionObject *functionObject, const Arg1 &arg1, const Arg2 &arg2)
+{
+    return (new typename SelectStoredFunctorPointerCall2<typename FunctionObject::result_type, FunctionObject, Arg1, Arg2>::type(functionObject, arg1, arg2))->start(pool);
+}
+template <typename FunctionObject, typename Arg1, typename Arg2, typename Arg3>
+QFuture<typename FunctionObject::result_type> run(QThreadPool *pool, FunctionObject *functionObject, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3)
+{
+    return (new typename SelectStoredFunctorPointerCall3<typename FunctionObject::result_type, FunctionObject, Arg1, Arg2, Arg3>::type(functionObject, arg1, arg2, arg3))->start(pool);
+}
+template <typename FunctionObject, typename Arg1, typename Arg2, typename Arg3, typename Arg4>
+QFuture<typename FunctionObject::result_type> run(QThreadPool *pool, FunctionObject *functionObject, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4)
+{
+    return (new typename SelectStoredFunctorPointerCall4<typename FunctionObject::result_type, FunctionObject, Arg1, Arg2, Arg3, Arg4>::type(functionObject, arg1, arg2, arg3, arg4))->start(pool);
+}
+template <typename FunctionObject, typename Arg1, typename Arg2, typename Arg3, typename Arg4, typename Arg5>
+QFuture<typename FunctionObject::result_type> run(QThreadPool *pool, FunctionObject *functionObject, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4, const Arg5 &arg5)
+{
+    return (new typename SelectStoredFunctorPointerCall5<typename FunctionObject::result_type, FunctionObject, Arg1, Arg2, Arg3, Arg4, Arg5>::type(functionObject, arg1, arg2, arg3, arg4, arg5))->start(pool);
+}
+
+template <typename T, typename Class>
+QFuture<T> run(QThreadPool *pool, const Class &object, T (Class::*fn)())
+{
+    return (new typename SelectStoredMemberFunctionCall0<T, Class>::type(fn, object))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1>
+QFuture<T> run(QThreadPool *pool, const Class &object, T (Class::*fn)(Param1), const Arg1 &arg1)
+{
+    return (new typename SelectStoredMemberFunctionCall1<T, Class, Param1, Arg1>::type(fn, object, arg1))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2>
+QFuture<T> run(QThreadPool *pool, const Class &object, T (Class::*fn)(Param1, Param2), const Arg1 &arg1, const Arg2 &arg2)
+{
+    return (new typename SelectStoredMemberFunctionCall2<T, Class, Param1, Arg1, Param2, Arg2>::type(fn, object, arg1, arg2))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3>
+QFuture<T> run(QThreadPool *pool, const Class &object, T (Class::*fn)(Param1, Param2, Param3), const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3)
+{
+    return (new typename SelectStoredMemberFunctionCall3<T, Class, Param1, Arg1, Param2, Arg2, Param3, Arg3>::type(fn, object, arg1, arg2, arg3))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3, typename Param4, typename Arg4>
+QFuture<T> run(QThreadPool *pool, const Class &object, T (Class::*fn)(Param1, Param2, Param3, Param4), const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4)
+{
+    return (new typename SelectStoredMemberFunctionCall4<T, Class, Param1, Arg1, Param2, Arg2, Param3, Arg3, Param4, Arg4>::type(fn, object, arg1, arg2, arg3, arg4))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3, typename Param4, typename Arg4, typename Param5, typename Arg5>
+QFuture<T> run(QThreadPool *pool, const Class &object, T (Class::*fn)(Param1, Param2, Param3, Param4, Param5), const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4, const Arg5 &arg5)
+{
+    return (new typename SelectStoredMemberFunctionCall5<T, Class, Param1, Arg1, Param2, Arg2, Param3, Arg3, Param4, Arg4, Param5, Arg5>::type(fn, object, arg1, arg2, arg3, arg4, arg5))->start(pool);
+}
+
+template <typename T, typename Class>
+QFuture<T> run(QThreadPool *pool, const Class &object, T (Class::*fn)() const)
+{
+    return (new typename SelectStoredConstMemberFunctionCall0<T, Class>::type(fn, object))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1>
+QFuture<T> run(QThreadPool *pool, const Class &object, T (Class::*fn)(Param1) const, const Arg1 &arg1)
+{
+    return (new typename SelectStoredConstMemberFunctionCall1<T, Class, Param1, Arg1>::type(fn, object, arg1))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2>
+QFuture<T> run(QThreadPool *pool, const Class &object, T (Class::*fn)(Param1, Param2) const, const Arg1 &arg1, const Arg2 &arg2)
+{
+    return (new typename SelectStoredConstMemberFunctionCall2<T, Class, Param1, Arg1, Param2, Arg2>::type(fn, object, arg1, arg2))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3>
+QFuture<T> run(QThreadPool *pool, const Class &object, T (Class::*fn)(Param1, Param2, Param3) const, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3)
+{
+    return (new typename SelectStoredConstMemberFunctionCall3<T, Class, Param1, Arg1, Param2, Arg2, Param3, Arg3>::type(fn, object, arg1, arg2, arg3))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3, typename Param4, typename Arg4>
+QFuture<T> run(QThreadPool *pool, const Class &object, T (Class::*fn)(Param1, Param2, Param3, Param4) const, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4)
+{
+    return (new typename SelectStoredConstMemberFunctionCall4<T, Class, Param1, Arg1, Param2, Arg2, Param3, Arg3, Param4, Arg4>::type(fn, object, arg1, arg2, arg3, arg4))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3, typename Param4, typename Arg4, typename Param5, typename Arg5>
+QFuture<T> run(QThreadPool *pool, const Class &object, T (Class::*fn)(Param1, Param2, Param3, Param4, Param5) const, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4, const Arg5 &arg5)
+{
+    return (new typename SelectStoredConstMemberFunctionCall5<T, Class, Param1, Arg1, Param2, Arg2, Param3, Arg3, Param4, Arg4, Param5, Arg5>::type(fn, object, arg1, arg2, arg3, arg4, arg5))->start(pool);
+}
+
+template <typename T, typename Class>
+QFuture<T> run(QThreadPool *pool, Class *object, T (Class::*fn)())
+{
+    return (new typename SelectStoredMemberFunctionPointerCall0<T, Class>::type(fn, object))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1>
+QFuture<T> run(QThreadPool *pool, Class *object, T (Class::*fn)(Param1), const Arg1 &arg1)
+{
+    return (new typename SelectStoredMemberFunctionPointerCall1<T, Class, Param1, Arg1>::type(fn, object, arg1))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2>
+QFuture<T> run(QThreadPool *pool, Class *object, T (Class::*fn)(Param1, Param2), const Arg1 &arg1, const Arg2 &arg2)
+{
+    return (new typename SelectStoredMemberFunctionPointerCall2<T, Class, Param1, Arg1, Param2, Arg2>::type(fn, object, arg1, arg2))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3>
+QFuture<T> run(QThreadPool *pool, Class *object, T (Class::*fn)(Param1, Param2, Param3), const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3)
+{
+    return (new typename SelectStoredMemberFunctionPointerCall3<T, Class, Param1, Arg1, Param2, Arg2, Param3, Arg3>::type(fn, object, arg1, arg2, arg3))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3, typename Param4, typename Arg4>
+QFuture<T> run(QThreadPool *pool, Class *object, T (Class::*fn)(Param1, Param2, Param3, Param4), const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4)
+{
+    return (new typename SelectStoredMemberFunctionPointerCall4<T, Class, Param1, Arg1, Param2, Arg2, Param3, Arg3, Param4, Arg4>::type(fn, object, arg1, arg2, arg3, arg4))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3, typename Param4, typename Arg4, typename Param5, typename Arg5>
+QFuture<T> run(QThreadPool *pool, Class *object, T (Class::*fn)(Param1, Param2, Param3, Param4, Param5), const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4, const Arg5 &arg5)
+{
+    return (new typename SelectStoredMemberFunctionPointerCall5<T, Class, Param1, Arg1, Param2, Arg2, Param3, Arg3, Param4, Arg4, Param5, Arg5>::type(fn, object, arg1, arg2, arg3, arg4, arg5))->start(pool);
+}
+
+template <typename T, typename Class>
+QFuture<T> run(QThreadPool *pool, const Class *object, T (Class::*fn)() const)
+{
+    return (new typename SelectStoredConstMemberFunctionPointerCall0<T, Class>::type(fn, object))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1>
+QFuture<T> run(QThreadPool *pool, const Class *object, T (Class::*fn)(Param1) const, const Arg1 &arg1)
+{
+    return (new typename SelectStoredConstMemberFunctionPointerCall1<T, Class, Param1, Arg1>::type(fn, object, arg1))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2>
+QFuture<T> run(QThreadPool *pool, const Class *object, T (Class::*fn)(Param1, Param2) const, const Arg1 &arg1, const Arg2 &arg2)
+{
+    return (new typename SelectStoredConstMemberFunctionPointerCall2<T, Class, Param1, Arg1, Param2, Arg2>::type(fn, object, arg1, arg2))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3>
+QFuture<T> run(QThreadPool *pool, const Class *object, T (Class::*fn)(Param1, Param2, Param3) const, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3)
+{
+    return (new typename SelectStoredConstMemberFunctionPointerCall3<T, Class, Param1, Arg1, Param2, Arg2, Param3, Arg3>::type(fn, object, arg1, arg2, arg3))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3, typename Param4, typename Arg4>
+QFuture<T> run(QThreadPool *pool, const Class *object, T (Class::*fn)(Param1, Param2, Param3, Param4) const, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4)
+{
+    return (new typename SelectStoredConstMemberFunctionPointerCall4<T, Class, Param1, Arg1, Param2, Arg2, Param3, Arg3, Param4, Arg4>::type(fn, object, arg1, arg2, arg3, arg4))->start(pool);
+}
+template <typename T, typename Class, typename Param1, typename Arg1, typename Param2, typename Arg2, typename Param3, typename Arg3, typename Param4, typename Arg4, typename Param5, typename Arg5>
+QFuture<T> run(QThreadPool *pool, const Class *object, T (Class::*fn)(Param1, Param2, Param3, Param4, Param5) const, const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3, const Arg4 &arg4, const Arg5 &arg5)
+{
+    return (new typename SelectStoredConstMemberFunctionPointerCall5<T, Class, Param1, Arg1, Param2, Arg2, Param3, Arg3, Param4, Arg4, Param5, Arg5>::type(fn, object, arg1, arg2, arg3, arg4, arg5))->start(pool);
+}
+
 } //namespace QtConcurrent
 
 #endif // Q_QDOC

src/concurrent/qtconcurrentrunbase.h

@@ -77,10 +77,16 @@ class RunFunctionTaskBase : public QFutureInterface<T> , public QRunnable
 public:
     QFuture<T> start()
     {
+        return start(QThreadPool::globalInstance());
+    }
+
+    QFuture<T> start(QThreadPool *pool)
+    {
+        this->setThreadPool(pool);
         this->setRunnable(this);
         this->reportStarted();
         QFuture<T> theFuture = this->future();
-        QThreadPool::globalInstance()->start(this, /*m_priority*/ 0);
+        pool->start(this, /*m_priority*/ 0);
         return theFuture;
     }
 

tests/auto/concurrent/qtconcurrentrun/tst_qtconcurrentrun.cpp

@@ -95,8 +95,9 @@ void tst_QtConcurrentRun::runLightFunction()
 
 void tst_QtConcurrentRun::runHeavyFunction()
 {
+    QThreadPool pool;
     qDebug("starting function");
-    QFuture<void> future = run(heavy);
+    QFuture<void> future = run(&pool, heavy);
     qDebug("waiting");
     future.waitForFinished();
     qDebug("done");
@@ -136,60 +137,95 @@ public:
 
 void tst_QtConcurrentRun::returnValue()
 {
+    QThreadPool pool;
     QFuture<int> f;
 
     f = run(returnInt0);
     QCOMPARE(f.result(), 10);
+    f = run(&pool, returnInt0);
+    QCOMPARE(f.result(), 10);
 
     A a;
     f = run(&a, &A::member0);
     QCOMPARE(f.result(), 10);
+    f = run(&pool, &a, &A::member0);
+    QCOMPARE(f.result(), 10);
 
     f = run(&a, &A::member1, 20);
     QCOMPARE(f.result(), 20);
+    f = run(&pool, &a, &A::member1, 20);
+    QCOMPARE(f.result(), 20);
 
     f = run(a, &A::member0);
     QCOMPARE(f.result(), 10);
+    f = run(&pool, a, &A::member0);
+    QCOMPARE(f.result(), 10);
 
     f = run(a, &A::member1, 20);
     QCOMPARE(f.result(), 20);
+    f = run(&pool, a, &A::member1, 20);
+    QCOMPARE(f.result(), 20);
 
     f = run(a);
     QCOMPARE(f.result(), 10);
+    f = run(&pool, a);
+    QCOMPARE(f.result(), 10);
 
     f = run(&a);
     QCOMPARE(f.result(), 10);
+    f = run(&pool, &a);
+    QCOMPARE(f.result(), 10);
 
     f = run(a, 20);
     QCOMPARE(f.result(), 20);
+    f = run(&pool, a, 20);
+    QCOMPARE(f.result(), 20);
 
     f = run(&a, 20);
     QCOMPARE(f.result(), 20);
+    f = run(&pool, &a, 20);
+    QCOMPARE(f.result(), 20);
 
     const AConst aConst = AConst();
     f = run(&aConst, &AConst::member0);
     QCOMPARE(f.result(), 10);
+    f = run(&pool, &aConst, &AConst::member0);
+    QCOMPARE(f.result(), 10);
 
     f = run(&aConst, &AConst::member1, 20);
     QCOMPARE(f.result(), 20);
+    f = run(&pool, &aConst, &AConst::member1, 20);
+    QCOMPARE(f.result(), 20);
 
     f = run(aConst, &AConst::member0);
     QCOMPARE(f.result(), 10);
+    f = run(&pool, aConst, &AConst::member0);
+    QCOMPARE(f.result(), 10);
 
     f = run(aConst, &AConst::member1, 20);
     QCOMPARE(f.result(), 20);
+    f = run(&pool, aConst, &AConst::member1, 20);
+    QCOMPARE(f.result(), 20);
 
     f = run(aConst);
     QCOMPARE(f.result(), 10);
+    f = run(&pool, aConst);
+    QCOMPARE(f.result(), 10);
 
     f = run(&aConst);
     QCOMPARE(f.result(), 10);
+    f = run(&pool, &aConst);
+    QCOMPARE(f.result(), 10);
 
     f = run(aConst, 20);
     QCOMPARE(f.result(), 20);
+    f = run(&pool, aConst, 20);
+    QCOMPARE(f.result(), 20);
 
     f = run(&aConst, 20);
     QCOMPARE(f.result(), 20);
+    f = run(&pool, &aConst, 20);
+    QCOMPARE(f.result(), 20);
 }
 
 struct TestClass
@@ -212,6 +248,7 @@ struct TestConstClass
 
 void tst_QtConcurrentRun::functionObject()
 {
+    QThreadPool pool;
     QFuture<void> f;
     TestClass c;
 
@@ -220,16 +257,28 @@ void tst_QtConcurrentRun::functionObject()
     f = run(c, 10);
     f = run(&c, 10);
 
+    f = run(&pool, c);
+    f = run(&pool, &c);
+    f = run(&pool, c, 10);
+    f = run(&pool, &c, 10);
+
     const TestConstClass cc = TestConstClass();
     f = run(cc);
     f = run(&cc);
     f = run(cc, 10);
     f = run(&cc, 10);
+
+    f = run(&pool, cc);
+    f = run(&pool, &cc);
+    f = run(&pool, cc, 10);
+    f = run(&pool, &cc, 10);
 }
 
 
 void tst_QtConcurrentRun::memberFunctions()
 {
+    QThreadPool pool;
+
     TestClass c;
 
     run(c, &TestClass::foo).waitForFinished();
@@ -237,11 +286,21 @@ void tst_QtConcurrentRun::memberFunctions()
     run(c, &TestClass::fooInt, 10).waitForFinished();
     run(&c, &TestClass::fooInt, 10).waitForFinished();
 
+    run(&pool, c, &TestClass::foo).waitForFinished();
+    run(&pool, &c, &TestClass::foo).waitForFinished();
+    run(&pool, c, &TestClass::fooInt, 10).waitForFinished();
+    run(&pool, &c, &TestClass::fooInt, 10).waitForFinished();
+
     const TestConstClass cc = TestConstClass();
     run(cc, &TestConstClass::foo).waitForFinished();
     run(&cc, &TestConstClass::foo).waitForFinished();
     run(cc, &TestConstClass::fooInt, 10).waitForFinished();
     run(&cc, &TestConstClass::fooInt, 10).waitForFinished();
+
+    run(&pool, cc, &TestConstClass::foo).waitForFinished();
+    run(&pool, &cc, &TestConstClass::foo).waitForFinished();
+    run(&pool, cc, &TestConstClass::fooInt, 10).waitForFinished();
+    run(&pool, &cc, &TestConstClass::fooInt, 10).waitForFinished();
 }
 
 
@@ -273,16 +332,25 @@ void stringIntFunction(QString)
 
 void tst_QtConcurrentRun::implicitConvertibleTypes()
 {
+    QThreadPool pool;
+
     double d;
     run(doubleFunction, d).waitForFinished();
+    run(&pool, doubleFunction, d).waitForFinished();
     int i;
     run(doubleFunction, d).waitForFinished();
+    run(&pool, doubleFunction, d).waitForFinished();
     run(doubleFunction, i).waitForFinished();
+    run(&pool, doubleFunction, i).waitForFinished();
     run(doubleFunction, 10).waitForFinished();
+    run(&pool, doubleFunction, 10).waitForFinished();
     run(stringFunction, QLatin1String("Foo")).waitForFinished();
+    run(&pool, stringFunction, QLatin1String("Foo")).waitForFinished();
     run(stringConstRefFunction, QLatin1String("Foo")).waitForFinished();
+    run(&pool, stringConstRefFunction, QLatin1String("Foo")).waitForFinished();
     QString string;
     run(stringRefFunction, string).waitForFinished();
+    run(&pool, stringRefFunction, string).waitForFinished();
 }
 
 void fn() { }
@@ -382,7 +450,10 @@ int throwFunctionReturn()
 
 void tst_QtConcurrentRun::exceptions()
 {
-    bool caught = false;
+    QThreadPool pool;
+    bool caught;
+
+    caught = false;
     try  {
         QtConcurrent::run(throwFunction).waitForFinished();
     } catch (QException &) {
@@ -391,6 +462,15 @@ void tst_QtConcurrentRun::exceptions()
     if (!caught)
         QFAIL("did not get exception");
 
+    caught = false;
+    try  {
+        QtConcurrent::run(&pool, throwFunction).waitForFinished();
+    } catch (QException &) {
+        caught = true;
+    }
+    if (!caught)
+        QFAIL("did not get exception");
+
     caught = false;
     try  {
         QtConcurrent::run(throwFunctionReturn).waitForFinished();
@@ -399,6 +479,15 @@ void tst_QtConcurrentRun::exceptions()
     }
     if (!caught)
         QFAIL("did not get exception");
+
+    caught = false;
+    try  {
+        QtConcurrent::run(&pool, throwFunctionReturn).waitForFinished();
+    } catch (QException &) {
+        caught = true;
+    }
+    if (!caught)
+        QFAIL("did not get exception");
 }
 #endif
 
@@ -438,6 +527,27 @@ void tst_QtConcurrentRun::functor()
         QtConcurrent::run(f, 1,2,3,4).waitForFinished();
         QtConcurrent::run(f, 1,2,3,4,5).waitForFinished();
     }
+    // and now with explicit pool:
+    QThreadPool pool;
+    {
+        QFuture<int> fut = QtConcurrent::run(&pool, f);
+        QCOMPARE(fut.result(), 42);
+    }
+    {
+        QFuture<double> fut = QtConcurrent::run(&pool, f, 8.5, 1.8);
+        QCOMPARE(fut.result(), (8.5/1.8));
+    }
+    {
+        QFuture<int> fut = QtConcurrent::run(&pool, f, 19, 3);
+        QCOMPARE(fut.result(), int(19/3));
+    }
+    {
+        QtConcurrent::run(&pool, f, 1).waitForFinished();
+        QtConcurrent::run(&pool, f, 1,2).waitForFinished();
+        QtConcurrent::run(&pool, f, 1,2,3).waitForFinished();
+        QtConcurrent::run(&pool, f, 1,2,3,4).waitForFinished();
+        QtConcurrent::run(&pool, f, 1,2,3,4,5).waitForFinished();
+    }
 }
 #endif
 
@@ -458,6 +568,22 @@ void tst_QtConcurrentRun::lambda()
         QCOMPARE(r, QStringList({"Hello", "World", "Foo"}));
     }
 #endif
+
+    // and now with explicit pool:
+    QThreadPool pool;
+    QCOMPARE(QtConcurrent::run(&pool, [](){ return 45; }).result(), 45);
+    QCOMPARE(QtConcurrent::run(&pool, [](int a){ return a+15; }, 12).result(), 12+15);
+    QCOMPARE(QtConcurrent::run(&pool, [](int a, double b){ return a + b; }, 12, 15).result(), double(12+15));
+    QCOMPARE(QtConcurrent::run(&pool, [](int a , int, int, int, int b){ return a + b; }, 1, 2, 3, 4, 5).result(), 1 + 5);
+
+#ifdef Q_COMPILER_INITIALIZER_LISTS
+    {
+        QString str { "Hello World Foo" };
+        QFuture<QStringList> f1 = QtConcurrent::run(&pool, [&](){ return str.split(' '); });
+        auto r = f1.result();
+        QCOMPARE(r, QStringList({"Hello", "World", "Foo"}));
+    }
+#endif
 }
 #endif