[futures.task] and [futures.async]. Requires variadics and rvalue-ref support.
llvm-svn: 112500
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: 27f000e10bee7e8320b79f1723dc5ca05ad52227
diff --git a/include/future b/include/future
index abfb77d..b75014a 100644
--- a/include/future
+++ b/include/future
@@ -399,11 +399,6 @@
// construction and destruction
packaged_task();
template <class F>
- explicit packaged_task(F f);
- template <class F, class Allocator>
- explicit packaged_task(allocator_arg_t, const Allocator& a, F f);
- explicit packaged_task(R(*f)(ArgTypes...));
- template <class F>
explicit packaged_task(F&& f);
template <class F, class Allocator>
explicit packaged_task(allocator_arg_t, const Allocator& a, F&& f);
@@ -538,7 +533,7 @@
unsigned __state_;
virtual void __on_zero_shared();
-
+ void __sub_wait(unique_lock<mutex>& __lk);
public:
enum
{
@@ -556,6 +551,8 @@
void __set_future_attached() {__state_ |= __future_attached;}
bool __has_future_attached() const {return __state_ & __future_attached;}
+ void __set_deferred() {__state_ |= deferred;}
+
void __make_ready();
bool __is_ready() const {return __state_ & ready;}
@@ -567,13 +564,15 @@
void copy();
- void wait() const;
+ void wait();
template <class _Rep, class _Period>
future_status
wait_for(const chrono::duration<_Rep, _Period>& __rel_time) const;
template <class _Clock, class _Duration>
future_status
wait_until(const chrono::time_point<_Clock, _Duration>& __abs_time) const;
+
+ virtual void __execute();
};
template <class _Clock, class _Duration>
@@ -581,12 +580,12 @@
__assoc_sub_state::wait_until(const chrono::time_point<_Clock, _Duration>& __abs_time) const
{
unique_lock<mutex> __lk(__mut_);
- while (!(__state_ & (ready | deferred)) && _Clock::now() < __abs_time)
+ if (__state_ & deferred)
+ return future_status::deferred;
+ while (!(__state_ & ready) && _Clock::now() < __abs_time)
__cv_.wait_until(__lk, __abs_time);
if (__state_ & ready)
return future_status::ready;
- if (__state_ & deferred)
- return future_status::deferred;
return future_status::timeout;
}
@@ -678,8 +677,7 @@
__assoc_state<_R>::move()
{
unique_lock<mutex> __lk(this->__mut_);
- while (!this->__is_ready())
- this->__cv_.wait(__lk);
+ this->__sub_wait(__lk);
if (this->__exception_ != nullptr)
rethrow_exception(this->__exception_);
return _STD::move(*reinterpret_cast<_R*>(&__value_));
@@ -690,8 +688,7 @@
__assoc_state<_R>::copy()
{
unique_lock<mutex> __lk(this->__mut_);
- while (!this->__is_ready())
- this->__cv_.wait(__lk);
+ this->__sub_wait(__lk);
if (this->__exception_ != nullptr)
rethrow_exception(this->__exception_);
return *reinterpret_cast<_R*>(&__value_);
@@ -753,8 +750,7 @@
__assoc_state<_R&>::copy()
{
unique_lock<mutex> __lk(this->__mut_);
- while (!this->__is_ready())
- this->__cv_.wait(__lk);
+ this->__sub_wait(__lk);
if (this->__exception_ != nullptr)
rethrow_exception(this->__exception_);
return *__value_;
@@ -829,10 +825,113 @@
__a.deallocate(this, 1);
}
+template <class _R, class _F>
+class __deferred_assoc_state
+ : public __assoc_state<_R>
+{
+ typedef __assoc_state<_R> base;
+
+ _F __func_;
+
+public:
+#ifdef _LIBCPP_MOVE
+ explicit __deferred_assoc_state(_F&& __f);
+#endif
+
+ virtual void __execute();
+};
+
+#ifdef _LIBCPP_MOVE
+
+template <class _R, class _F>
+inline _LIBCPP_INLINE_VISIBILITY
+__deferred_assoc_state<_R, _F>::__deferred_assoc_state(_F&& __f)
+ : __func_(_STD::forward<_F>(__f))
+{
+ this->__set_deferred();
+}
+
+#endif // _LIBCPP_MOVE
+
+template <class _R, class _F>
+void
+__deferred_assoc_state<_R, _F>::__execute()
+{
+#ifndef _LIBCPP_NO_EXCEPTIONS
+ try
+ {
+#endif // _LIBCPP_NO_EXCEPTIONS
+ this->set_value(__func_());
+#ifndef _LIBCPP_NO_EXCEPTIONS
+ }
+ catch (...)
+ {
+ this->set_exception(current_exception());
+ }
+#endif // _LIBCPP_NO_EXCEPTIONS
+}
+
+template <class _F>
+class __deferred_assoc_state<void, _F>
+ : public __assoc_sub_state
+{
+ typedef __assoc_sub_state base;
+
+ _F __func_;
+
+public:
+#ifdef _LIBCPP_MOVE
+ explicit __deferred_assoc_state(_F&& __f);
+#endif
+
+ virtual void __execute();
+};
+
+#ifdef _LIBCPP_MOVE
+
+template <class _F>
+inline _LIBCPP_INLINE_VISIBILITY
+__deferred_assoc_state<void, _F>::__deferred_assoc_state(_F&& __f)
+ : __func_(_STD::forward<_F>(__f))
+{
+ this->__set_deferred();
+}
+
+#endif // _LIBCPP_MOVE
+
+template <class _F>
+void
+__deferred_assoc_state<void, _F>::__execute()
+{
+#ifndef _LIBCPP_NO_EXCEPTIONS
+ try
+ {
+#endif // _LIBCPP_NO_EXCEPTIONS
+ __func_();
+ this->set_value();
+#ifndef _LIBCPP_NO_EXCEPTIONS
+ }
+ catch (...)
+ {
+ this->set_exception(current_exception());
+ }
+#endif // _LIBCPP_NO_EXCEPTIONS
+}
+
template <class> class promise;
// future
+template <class _R> class future;
+
+template <class _R, class _F>
+future<_R>
+#ifdef _LIBCPP_MOVE
+__make_deferred_assoc_state(_F&& __f);
+#else
+__make_deferred_assoc_state(_F __f);
+#endif
+
template <class _R>
class future
{
@@ -841,6 +940,14 @@
explicit future(__assoc_state<_R>* __state);
template <class> friend class promise;
+
+ template <class _R1, class _F>
+#ifdef _LIBCPP_MOVE
+ friend future<_R1> __make_deferred_assoc_state(_F&& __f);
+#else
+ friend future<_R1> __make_deferred_assoc_state(_F __f);
+#endif
+
public:
future() : __state_(nullptr) {}
#ifdef _LIBCPP_MOVE
@@ -887,8 +994,14 @@
if (__state_->__has_future_attached())
throw future_error(make_error_code(future_errc::future_already_retrieved));
__state_->__add_shared();
+ __state_->__set_future_attached();
}
+struct __release_shared_count
+{
+ void operator()(__shared_count* p) {p->__release_shared();}
+};
+
template <class _R>
future<_R>::~future()
{
@@ -900,6 +1013,7 @@
_R
future<_R>::get()
{
+ unique_ptr<__shared_count, __release_shared_count> __(__state_);
__assoc_state<_R>* __s = __state_;
__state_ = nullptr;
return __s->move();
@@ -913,6 +1027,14 @@
explicit future(__assoc_state<_R&>* __state);
template <class> friend class promise;
+
+ template <class _R1, class _F>
+#ifdef _LIBCPP_MOVE
+ friend future<_R1> __make_deferred_assoc_state(_F&& __f);
+#else
+ friend future<_R1> __make_deferred_assoc_state(_F __f);
+#endif
+
public:
future() : __state_(nullptr) {}
#ifdef _LIBCPP_MOVE
@@ -959,6 +1081,7 @@
if (__state_->__has_future_attached())
throw future_error(make_error_code(future_errc::future_already_retrieved));
__state_->__add_shared();
+ __state_->__set_future_attached();
}
template <class _R>
@@ -972,6 +1095,7 @@
_R&
future<_R&>::get()
{
+ unique_ptr<__shared_count, __release_shared_count> __(__state_);
__assoc_state<_R&>* __s = __state_;
__state_ = nullptr;
return __s->copy();
@@ -985,6 +1109,14 @@
explicit future(__assoc_sub_state* __state);
template <class> friend class promise;
+
+ template <class _R1, class _F>
+#ifdef _LIBCPP_MOVE
+ friend future<_R1> __make_deferred_assoc_state(_F&& __f);
+#else
+ friend future<_R1> __make_deferred_assoc_state(_F __f);
+#endif
+
public:
future() : __state_(nullptr) {}
#ifdef _LIBCPP_MOVE
@@ -1026,10 +1158,16 @@
// promise<R>
+template <class> class packaged_task;
+
template <class _R>
class promise
{
__assoc_state<_R>* __state_;
+
+ explicit promise(nullptr_t) : __state_(nullptr) {}
+
+ template <class> friend class packaged_task;
public:
promise();
template <class _Alloc>
@@ -1186,6 +1324,11 @@
class promise<_R&>
{
__assoc_state<_R&>* __state_;
+
+ explicit promise(nullptr_t) : __state_(nullptr) {}
+
+ template <class> friend class packaged_task;
+
public:
promise();
template <class _Allocator>
@@ -1310,6 +1453,11 @@
class promise<void>
{
__assoc_sub_state* __state_;
+
+ explicit promise(nullptr_t) : __state_(nullptr) {}
+
+ template <class> friend class packaged_task;
+
public:
promise();
template <class _Allocator>
@@ -1374,6 +1522,534 @@
template <class _R, class _Alloc>
struct uses_allocator<promise<_R>, _Alloc> : public true_type {};
+#ifndef _LIBCPP_HAS_NO_VARIADICS
+
+// packaged_task
+
+template<class _Fp> class __packaged_task_base;
+
+template<class _R, class ..._ArgTypes>
+class __packaged_task_base<_R(_ArgTypes...)>
+{
+ __packaged_task_base(const __packaged_task_base&);
+ __packaged_task_base& operator=(const __packaged_task_base&);
+public:
+ __packaged_task_base() {}
+ virtual ~__packaged_task_base() {}
+ virtual void __move_to(__packaged_task_base*) = 0;
+ virtual void destroy() = 0;
+ virtual void destroy_deallocate() = 0;
+ virtual _R operator()(_ArgTypes&& ...) = 0;
+};
+
+template<class _FD, class _Alloc, class _FB> class __packaged_task_func;
+
+template<class _F, class _Alloc, class _R, class ..._ArgTypes>
+class __packaged_task_func<_F, _Alloc, _R(_ArgTypes...)>
+ : public __packaged_task_base<_R(_ArgTypes...)>
+{
+ __compressed_pair<_F, _Alloc> __f_;
+public:
+ explicit __packaged_task_func(const _F& __f) : __f_(__f) {}
+ explicit __packaged_task_func(_F&& __f) : __f_(_STD::move(__f)) {}
+ __packaged_task_func(const _F& __f, const _Alloc& __a)
+ : __f_(__f, __a) {}
+ __packaged_task_func(_F&& __f, const _Alloc& __a)
+ : __f_(_STD::move(__f), __a) {}
+ virtual void __move_to(__packaged_task_base<_R(_ArgTypes...)>*);
+ virtual void destroy();
+ virtual void destroy_deallocate();
+ virtual _R operator()(_ArgTypes&& ... __args);
+};
+
+template<class _F, class _Alloc, class _R, class ..._ArgTypes>
+void
+__packaged_task_func<_F, _Alloc, _R(_ArgTypes...)>::__move_to(
+ __packaged_task_base<_R(_ArgTypes...)>* __p)
+{
+ ::new (__p) __packaged_task_func(_STD::move(__f_.first()), _STD::move(__f_.second()));
+}
+
+template<class _F, class _Alloc, class _R, class ..._ArgTypes>
+void
+__packaged_task_func<_F, _Alloc, _R(_ArgTypes...)>::destroy()
+{
+ __f_.~__compressed_pair<_F, _Alloc>();
+}
+
+template<class _F, class _Alloc, class _R, class ..._ArgTypes>
+void
+__packaged_task_func<_F, _Alloc, _R(_ArgTypes...)>::destroy_deallocate()
+{
+ typedef typename _Alloc::template rebind<__packaged_task_func>::other _A;
+ _A __a(__f_.second());
+ __f_.~__compressed_pair<_F, _Alloc>();
+ __a.deallocate(this, 1);
+}
+
+template<class _F, class _Alloc, class _R, class ..._ArgTypes>
+_R
+__packaged_task_func<_F, _Alloc, _R(_ArgTypes...)>::operator()(_ArgTypes&& ... __arg)
+{
+ return __invoke(__f_.first(), _STD::forward<_ArgTypes>(__arg)...);
+}
+
+template <class> class __packaged_task_function;
+
+template<class _R, class ..._ArgTypes>
+class __packaged_task_function<_R(_ArgTypes...)>
+{
+ typedef __packaged_task_base<_R(_ArgTypes...)> __base;
+ aligned_storage<3*sizeof(void*)>::type __buf_;
+ __base* __f_;
+
+public:
+ typedef _R result_type;
+
+ // construct/copy/destroy:
+ __packaged_task_function() : __f_(nullptr) {}
+ template<class _F>
+ __packaged_task_function(_F&& __f);
+ template<class _F, class _Alloc>
+ __packaged_task_function(allocator_arg_t, const _Alloc& __a, _F&& __f);
+
+ __packaged_task_function(__packaged_task_function&&);
+ __packaged_task_function& operator=(__packaged_task_function&&);
+
+ __packaged_task_function(const __packaged_task_function&) = delete;
+ __packaged_task_function& operator=(const __packaged_task_function&) = delete;
+
+ ~__packaged_task_function();
+
+ void swap(__packaged_task_function&);
+
+ _R operator()(_ArgTypes...) const;
+};
+
+template<class _R, class ..._ArgTypes>
+__packaged_task_function<_R(_ArgTypes...)>::__packaged_task_function(__packaged_task_function&& __f)
+{
+ if (__f.__f_ == nullptr)
+ __f_ = nullptr;
+ else if (__f.__f_ == (__base*)&__f.__buf_)
+ {
+ __f_ = (__base*)&__buf_;
+ __f.__f_->__move_to(__f_);
+ }
+ else
+ {
+ __f_ = __f.__f_;
+ __f.__f_ = nullptr;
+ }
+}
+
+template<class _R, class ..._ArgTypes>
+template <class _F>
+__packaged_task_function<_R(_ArgTypes...)>::__packaged_task_function(_F&& __f)
+ : __f_(nullptr)
+{
+ typedef typename remove_reference<_F>::type _FR;
+ typedef __packaged_task_func<_FR, allocator<_FR>, _R(_ArgTypes...)> _FF;
+ if (sizeof(_FF) <= sizeof(__buf_))
+ {
+ __f_ = (__base*)&__buf_;
+ ::new (__f_) _FF(_STD::forward<_F>(__f));
+ }
+ else
+ {
+ typedef allocator<_FF> _A;
+ _A __a;
+ typedef __allocator_destructor<_A> _D;
+ unique_ptr<__base, _D> __hold(__a.allocate(1), _D(__a, 1));
+ ::new (__hold.get()) _FF(_STD::forward<_F>(__f), allocator<_FR>(__a));
+ __f_ = __hold.release();
+ }
+}
+
+template<class _R, class ..._ArgTypes>
+template <class _F, class _Alloc>
+__packaged_task_function<_R(_ArgTypes...)>::__packaged_task_function(
+ allocator_arg_t, const _Alloc& __a0, _F&& __f)
+ : __f_(nullptr)
+{
+ typedef allocator_traits<_Alloc> __alloc_traits;
+ typedef typename remove_reference<_F>::type _FR;
+ typedef __packaged_task_func<_FR, _Alloc, _R(_ArgTypes...)> _FF;
+ if (sizeof(_FF) <= sizeof(__buf_))
+ {
+ __f_ = (__base*)&__buf_;
+ ::new (__f_) _FF(_STD::forward<_F>(__f));
+ }
+ else
+ {
+ typedef typename __alloc_traits::template
+#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
+ rebind_alloc<_FF>
+#else
+ rebind_alloc<_FF>::other
+#endif
+ _A;
+ _A __a(__a0);
+ typedef __allocator_destructor<_A> _D;
+ unique_ptr<__base, _D> __hold(__a.allocate(1), _D(__a, 1));
+ ::new (__hold.get()) _FF(_STD::forward<_F>(__f), _Alloc(__a));
+ __f_ = __hold.release();
+ }
+}
+
+template<class _R, class ..._ArgTypes>
+__packaged_task_function<_R(_ArgTypes...)>&
+__packaged_task_function<_R(_ArgTypes...)>::operator=(__packaged_task_function&& __f)
+{
+ if (__f_ == (__base*)&__buf_)
+ __f_->destroy();
+ else if (__f_)
+ __f_->destroy_deallocate();
+ __f_ = nullptr;
+ if (__f.__f_ == nullptr)
+ __f_ = nullptr;
+ else if (__f.__f_ == (__base*)&__f.__buf_)
+ {
+ __f_ = (__base*)&__buf_;
+ __f.__f_->__move_to(__f_);
+ }
+ else
+ {
+ __f_ = __f.__f_;
+ __f.__f_ = nullptr;
+ }
+}
+
+template<class _R, class ..._ArgTypes>
+__packaged_task_function<_R(_ArgTypes...)>::~__packaged_task_function()
+{
+ if (__f_ == (__base*)&__buf_)
+ __f_->destroy();
+ else if (__f_)
+ __f_->destroy_deallocate();
+}
+
+template<class _R, class ..._ArgTypes>
+void
+__packaged_task_function<_R(_ArgTypes...)>::swap(__packaged_task_function& __f)
+{
+ if (__f_ == (__base*)&__buf_ && __f.__f_ == (__base*)&__f.__buf_)
+ {
+ typename aligned_storage<sizeof(__buf_)>::type __tempbuf;
+ __base* __t = (__base*)&__tempbuf;
+ __f_->__move_to(__t);
+ __f_->destroy();
+ __f_ = nullptr;
+ __f.__f_->__move_to((__base*)&__buf_);
+ __f.__f_->destroy();
+ __f.__f_ = nullptr;
+ __f_ = (__base*)&__buf_;
+ __t->__move_to((__base*)&__f.__buf_);
+ __t->destroy();
+ __f.__f_ = (__base*)&__f.__buf_;
+ }
+ else if (__f_ == (__base*)&__buf_)
+ {
+ __f_->__move_to((__base*)&__f.__buf_);
+ __f_->destroy();
+ __f_ = __f.__f_;
+ __f.__f_ = (__base*)&__f.__buf_;
+ }
+ else if (__f.__f_ == (__base*)&__f.__buf_)
+ {
+ __f.__f_->__move_to((__base*)&__buf_);
+ __f.__f_->destroy();
+ __f.__f_ = __f_;
+ __f_ = (__base*)&__buf_;
+ }
+ else
+ _STD::swap(__f_, __f.__f_);
+}
+
+template<class _R, class ..._ArgTypes>
+inline _LIBCPP_INLINE_VISIBILITY
+_R
+__packaged_task_function<_R(_ArgTypes...)>::operator()(_ArgTypes... __arg) const
+{
+ return (*__f_)(_STD::forward<_ArgTypes>(__arg)...);
+}
+
+template<class _R, class ..._ArgTypes>
+class packaged_task<_R(_ArgTypes...)>
+{
+public:
+ typedef _R result_type;
+
+private:
+ __packaged_task_function<result_type(_ArgTypes...)> __f_;
+ promise<result_type> __p_;
+
+public:
+ // construction and destruction
+ packaged_task() : __p_(nullptr) {}
+ template <class _F>
+ explicit packaged_task(_F&& __f) : __f_(_STD::forward<_F>(__f)) {}
+ template <class _F, class _Allocator>
+ explicit packaged_task(allocator_arg_t, const _Allocator& __a, _F&& __f)
+ : __f_(allocator_arg, __a, _STD::forward<_F>(__f)),
+ __p_(allocator_arg, __a) {}
+ // ~packaged_task() = default;
+
+ // no copy
+ packaged_task(packaged_task&) = delete;
+ packaged_task& operator=(packaged_task&) = delete;
+
+ // move support
+ packaged_task(packaged_task&& __other)
+ : __f_(_STD::move(__other.__f_)), __p_(_STD::move(__other.__p_)) {}
+ packaged_task& operator=(packaged_task&& __other)
+ {
+ __f_ = _STD::move(__other.__f_);
+ __p_ = _STD::move(__other.__p_);
+ return *this;
+ }
+ void swap(packaged_task& __other)
+ {
+ __f_.swap(__other.__f_);
+ __p_.swap(__other.__p_);
+ }
+
+ //explicit
+ operator bool() const {return __p_.__state_ != nullptr;}
+
+ // result retrieval
+ future<result_type> get_future() {return __p_.get_future();}
+
+ // execution
+ void operator()(_ArgTypes... __args);
+ void make_ready_at_thread_exit(_ArgTypes... __args);
+
+ void reset();
+};
+
+template<class _R, class ..._ArgTypes>
+void
+packaged_task<_R(_ArgTypes...)>::operator()(_ArgTypes... __args)
+{
+#ifndef _LIBCPP_NO_EXCEPTIONS
+ if (__p_.__state_ == nullptr)
+ throw future_error(make_error_code(future_errc::no_state));
+ if (__p_.__state_->__has_value())
+ throw future_error(make_error_code(future_errc::promise_already_satisfied));
+ try
+ {
+#endif // _LIBCPP_NO_EXCEPTIONS
+ __p_.set_value(__f_(_STD::forward<_ArgTypes>(__args)...));
+#ifndef _LIBCPP_NO_EXCEPTIONS
+ }
+ catch (...)
+ {
+ __p_.set_exception(current_exception());
+ }
+#endif // _LIBCPP_NO_EXCEPTIONS
+}
+
+template<class _R, class ..._ArgTypes>
+void
+packaged_task<_R(_ArgTypes...)>::make_ready_at_thread_exit(_ArgTypes... __args)
+{
+#ifndef _LIBCPP_NO_EXCEPTIONS
+ if (__p_.__state_ == nullptr)
+ throw future_error(make_error_code(future_errc::no_state));
+ if (__p_.__state_->__has_value())
+ throw future_error(make_error_code(future_errc::promise_already_satisfied));
+ try
+ {
+#endif // _LIBCPP_NO_EXCEPTIONS
+ __p_.set_value_at_thread_exit(__f_(_STD::forward<_ArgTypes>(__args)...));
+#ifndef _LIBCPP_NO_EXCEPTIONS
+ }
+ catch (...)
+ {
+ __p_.set_exception_at_thread_exit(current_exception());
+ }
+#endif // _LIBCPP_NO_EXCEPTIONS
+}
+
+template<class _R, class ..._ArgTypes>
+void
+packaged_task<_R(_ArgTypes...)>::reset()
+{
+#ifndef _LIBCPP_NO_EXCEPTIONS
+ if (!(*this))
+ throw future_error(make_error_code(future_errc::no_state));
+#endif // _LIBCPP_NO_EXCEPTIONS
+ __p_ = promise<result_type>();
+}
+
+template<class ..._ArgTypes>
+class packaged_task<void(_ArgTypes...)>
+{
+public:
+ typedef void result_type;
+
+private:
+ __packaged_task_function<result_type(_ArgTypes...)> __f_;
+ promise<result_type> __p_;
+
+public:
+ // construction and destruction
+ packaged_task() : __p_(nullptr) {}
+ template <class _F>
+ explicit packaged_task(_F&& __f) : __f_(_STD::forward<_F>(__f)) {}
+ template <class _F, class _Allocator>
+ explicit packaged_task(allocator_arg_t, const _Allocator& __a, _F&& __f)
+ : __f_(allocator_arg, __a, _STD::forward<_F>(__f)),
+ __p_(allocator_arg, __a) {}
+ // ~packaged_task() = default;
+
+ // no copy
+ packaged_task(packaged_task&) = delete;
+ packaged_task& operator=(packaged_task&) = delete;
+
+ // move support
+ packaged_task(packaged_task&& __other)
+ : __f_(_STD::move(__other.__f_)), __p_(_STD::move(__other.__p_)) {}
+ packaged_task& operator=(packaged_task&& __other)
+ {
+ __f_ = _STD::move(__other.__f_);
+ __p_ = _STD::move(__other.__p_);
+ return *this;
+ }
+ void swap(packaged_task& __other)
+ {
+ __f_.swap(__other.__f_);
+ __p_.swap(__other.__p_);
+ }
+
+ //explicit
+ operator bool() const {return __p_.__state_ != nullptr;}
+
+ // result retrieval
+ future<result_type> get_future() {return __p_.get_future();}
+
+ // execution
+ void operator()(_ArgTypes... __args);
+ void make_ready_at_thread_exit(_ArgTypes... __args);
+
+ void reset();
+};
+
+template<class ..._ArgTypes>
+void
+packaged_task<void(_ArgTypes...)>::operator()(_ArgTypes... __args)
+{
+#ifndef _LIBCPP_NO_EXCEPTIONS
+ if (__p_.__state_ == nullptr)
+ throw future_error(make_error_code(future_errc::no_state));
+ if (__p_.__state_->__has_value())
+ throw future_error(make_error_code(future_errc::promise_already_satisfied));
+ try
+ {
+#endif // _LIBCPP_NO_EXCEPTIONS
+ __f_(_STD::forward<_ArgTypes>(__args)...);
+ __p_.set_value();
+#ifndef _LIBCPP_NO_EXCEPTIONS
+ }
+ catch (...)
+ {
+ __p_.set_exception(current_exception());
+ }
+#endif // _LIBCPP_NO_EXCEPTIONS
+}
+
+template<class ..._ArgTypes>
+void
+packaged_task<void(_ArgTypes...)>::make_ready_at_thread_exit(_ArgTypes... __args)
+{
+#ifndef _LIBCPP_NO_EXCEPTIONS
+ if (__p_.__state_ == nullptr)
+ throw future_error(make_error_code(future_errc::no_state));
+ if (__p_.__state_->__has_value())
+ throw future_error(make_error_code(future_errc::promise_already_satisfied));
+ try
+ {
+#endif // _LIBCPP_NO_EXCEPTIONS
+ __f_(_STD::forward<_ArgTypes>(__args)...);
+ __p_.set_value_at_thread_exit();
+#ifndef _LIBCPP_NO_EXCEPTIONS
+ }
+ catch (...)
+ {
+ __p_.set_exception_at_thread_exit(current_exception());
+ }
+#endif // _LIBCPP_NO_EXCEPTIONS
+}
+
+template<class ..._ArgTypes>
+void
+packaged_task<void(_ArgTypes...)>::reset()
+{
+#ifndef _LIBCPP_NO_EXCEPTIONS
+ if (!(*this))
+ throw future_error(make_error_code(future_errc::no_state));
+#endif // _LIBCPP_NO_EXCEPTIONS
+ __p_ = promise<result_type>();
+}
+
+template <class _Callable>
+inline _LIBCPP_INLINE_VISIBILITY
+void
+swap(packaged_task<_Callable>& __x, packaged_task<_Callable>& __y)
+{
+ __x.swap(__y);
+}
+
+template <class _Callable, class _Alloc>
+struct uses_allocator<packaged_task<_Callable>, _Alloc> : public true_type {};
+
+template <class _R, class _F>
+future<_R>
+#ifdef _LIBCPP_MOVE
+__make_deferred_assoc_state(_F&& __f)
+#else
+__make_deferred_assoc_state(_F __f)
+#endif
+{
+ unique_ptr<__deferred_assoc_state<_R, _F>, __release_shared_count>
+ __h(new __deferred_assoc_state<_R, _F>(_STD::forward<_F>(__f)));
+ return future<_R>(__h.get());
+}
+
+template <class _F, class... _Args>
+future<typename result_of<_F(_Args...)>::type>
+async(launch __policy, _F&& __f, _Args&&... __args)
+{
+ typedef typename result_of<_F(_Args...)>::type _R;
+ future<_R> __r;
+ if (__policy == launch::sync)
+ __r = _STD::__make_deferred_assoc_state<_R>(bind(_STD::forward<_F>(__f),
+ _STD::forward<_Args>(__args)...));
+ else
+ {
+ packaged_task<_R()> __pk(bind(_STD::forward<_F>(__f),
+ _STD::forward<_Args>(__args)...));
+ __r = __pk.get_future();
+ thread(_STD::move(__pk)).detach();
+ }
+ return __r;
+}
+
+template <class _F, class... _Args>
+inline _LIBCPP_INLINE_VISIBILITY
+typename enable_if
+<
+ !is_same<typename decay<_F>::type, launch>::value,
+ future<typename result_of<_F(_Args...)>::type>
+>::type
+async(_F&& __f, _Args&&... __args)
+{
+ return async(launch::any, _STD::forward<_F>(__f),
+ _STD::forward<_Args>(__args)...);
+}
+
+#endif // _LIBCPP_HAS_NO_VARIADICS
+
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP_FUTURE