Implements the functionality of futures. More...

#include <future.h>

Inheritance diagram for madness::FutureImpl< T >:

Collaboration diagram for madness::FutureImpl< T >:

[legend]

Public Member Functions
	FutureImpl ()
	Constructor that uses a local unassigned value.

	FutureImpl (const RemoteReference< FutureImpl< T > > &remote_ref)
	Constructor that uses a wrapper for a remote future.

virtual	~FutureImpl ()
	Destructor.

T &	get (bool dowork=true)
	Gets/forces the value, waiting if necessary.

const T &	get (bool dowork=true) const
	Gets/forces the value, waiting if necessary.

bool	is_local () const

bool	probe () const
	Checks if the value has been assigned.

void	register_callback (CallbackInterface *callback)
	Registers a function to be invoked when future is assigned.

bool	replace_with (FutureImpl< T > *f)

void	set (const archive::BufferInputArchive &input_arch)

template<typename U >
void	set (U &&value)
	Sets the value of the future (assignment).

Private Types
typedef Stack< std::shared_ptr< FutureImpl< T > >, MAXCALLBACKS >	assignmentT
	Assignment type.

typedef Stack< CallbackInterface *, MAXCALLBACKS >	callbackT
	Callback type.

Private Member Functions
void	add_to_assignments (const std::shared_ptr< FutureImpl< T > > f)
	Pass by value with implied copy to manage lifetime of `f`.

void	set_assigned (const T &value)

Private Member Functions inherited from madness::Spinlock
	Spinlock (int junk=0)
	Make and initialize a spinlock ... initial state is unlocked.

virtual	~Spinlock ()

void	lock () const
	Acquire the spinlock waiting if necessary.

bool	try_lock () const
	Try to acquire the spinlock ... return true on success, false on failure.

void	unlock () const
	Free a spinlock owned by this thread.

Static Private Member Functions
static void	set_handler (const AmArg &arg)
	AM handler for remote set operations.

Private Attributes
std::atomic< bool >	assigned
	A flag indicating if the future has been set.

volatile assignmentT	assignments

volatile callbackT	callbacks

RemoteReference< FutureImpl< T > >	remote_ref
	Reference to a remote future pimpl.

volatile T	t
	The future data.

Static Private Attributes
static const int	MAXCALLBACKS = 4

Friends
class	Future< T >

std::ostream &	operator<< (std::ostream &out, const Future< T > &f)
	Human readable printing of a `Future` to a stream.

Detailed Description

template<typename T>
class madness::FutureImpl< T >

Implements the functionality of futures.

Template Parameters

T	The type of future.

Member Typedef Documentation

◆ assignmentT

template<typename T >

typedef Stack<std::shared_ptr<FutureImpl<T> >,MAXCALLBACKS> madness::FutureImpl< T >::assignmentT

private

Assignment type.

◆ callbackT

template<typename T >

typedef Stack<CallbackInterface*, MAXCALLBACKS> madness::FutureImpl< T >::callbackT

private

Callback type.

Constructor & Destructor Documentation

◆ FutureImpl() [1/2]

template<typename T >

madness::FutureImpl< T >::FutureImpl ( )

inline

Constructor that uses a local unassigned value.

◆ FutureImpl() [2/2]

template<typename T >

madness::FutureImpl< T >::FutureImpl ( const RemoteReference< FutureImpl< T > > & remote_ref )

inline

Constructor that uses a wrapper for a remote future.

Todo:: Description needed.

Parameters

[in] remote_ref Description needed.

◆ ~FutureImpl()

template<typename T >

virtual madness::FutureImpl< T >::~FutureImpl ( )

inlinevirtual

Destructor.

Todo:: Perhaps a comment about its behavior.

References madness::FutureImpl< T >::assigned, madness::FutureImpl< T >::assignments, madness::FutureImpl< T >::callbacks, and madness::print().

Member Function Documentation

◆ add_to_assignments()

template<typename T >

void madness::FutureImpl< T >::add_to_assignments ( const std::shared_ptr< FutureImpl< T > > f )

inlineprivate

Pass by value with implied copy to manage lifetime of f.

Todo:: Description needed.

Parameters

[in] f Description needed.

References madness::FutureImpl< T >::assigned, madness::FutureImpl< T >::assignments, madness::f, T(), and madness::FutureImpl< T >::t.

◆ get() [1/2]

template<typename T >

T & madness::FutureImpl< T >::get ( bool dowork = true )

inline

Gets/forces the value, waiting if necessary.

Parameters

dowork If true (default) and the future is not ready this thread will execute other tasks while waiting

Warning: PaRSEC backend does not support dowork=true from a callstack containing a running MADNESS task already, hence must use dowork=false when need to call from within a task

Returns: reference to the contained value

Precondition: this->is_local()

References madness::World::await(), MADNESS_ASSERT, madness::FutureImpl< T >::probe(), madness::FutureImpl< T >::remote_ref, T(), and madness::FutureImpl< T >::t.

Referenced by madness::WorldContainerImpl< keyT, valueT, hashfunT >::find_failure_handler(), and madness::WorldContainerImpl< keyT, valueT, hashfunT >::find_success_handler().

◆ get() [2/2]

template<typename T >

const T & madness::FutureImpl< T >::get ( bool dowork = true ) const

inline

Gets/forces the value, waiting if necessary.

Parameters

dowork If true (default) and the future is not ready this thread will execute other tasks while waiting

Warning: PaRSEC backend does not support dowork=true from a callstack containing a running MADNESS task already, hence must use dowork=false when need to call from within a task

Returns: reference to the contained value

Precondition: this->is_local()

References madness::World::await(), MADNESS_ASSERT, madness::FutureImpl< T >::probe(), madness::FutureImpl< T >::remote_ref, T(), and madness::FutureImpl< T >::t.

◆ is_local()

template<typename T >

bool madness::FutureImpl< T >::is_local ( ) const

inline

Todo:: Brief description needed.

Todo:: Description needed.

Returns: Description needed.

References madness::FutureImpl< T >::remote_ref.

◆ probe()

template<typename T >

bool madness::FutureImpl< T >::probe ( ) const

inline

Checks if the value has been assigned.

Returns: True if the value has been assigned; false otherwise.

References madness::FutureImpl< T >::assigned.

Referenced by madness::FutureImpl< T >::get(), and madness::FutureImpl< T >::get().

◆ register_callback()

template<typename T >

void madness::FutureImpl< T >::register_callback ( CallbackInterface * callback )

inline

Registers a function to be invoked when future is assigned.

Callbacks are invoked in the order registered. If the future is already assigned, the callback is immediately invoked.

Todo:: Description needed.

Parameters

callback Description needed.

References madness::FutureImpl< T >::assigned, madness::FutureImpl< T >::callbacks, fred(), and madness::CallbackInterface::notify().

◆ replace_with()

template<typename T >

bool madness::FutureImpl< T >::replace_with ( FutureImpl< T > * f )

inline

Todo:: Brief description needed.

Todo:

Is this function needed?

Details needed.

Parameters

f	Description needed.

Returns: Description needed.

References MADNESS_EXCEPTION.

◆ set() [1/2]

template<typename T >

void madness::FutureImpl< T >::set ( const archive::BufferInputArchive & input_arch )

inline

Todo:: Brief description needed.

Todo:: Descriptions needed.

Parameters

[in] input_arch Description needed.

References fred(), MADNESS_ASSERT, madness::FutureImpl< T >::remote_ref, madness::FutureImpl< T >::set_assigned(), T(), and madness::FutureImpl< T >::t.

◆ set() [2/2]

template<typename T >

template<typename U >

void madness::FutureImpl< T >::set ( U && value )

inline

Sets the value of the future (assignment).

Todo:: Descriptions needed.

Template Parameters

U	Description needed.

Parameters

[in] value Description needed.

References madness::World::am, fred(), madness::new_am_arg(), madness::FutureImpl< T >::remote_ref, madness::WorldAmInterface::send(), madness::FutureImpl< T >::set_assigned(), T(), and madness::FutureImpl< T >::t.

◆ set_assigned()

template<typename T >

void madness::FutureImpl< T >::set_assigned ( const T & value )

inlineprivate

Todo:: Brief description needed.

Invoked locally by set routine after assignment.

Todo:: Description needed.

Parameters

[in] value Description needed.

References madness::FutureImpl< T >::assigned, madness::FutureImpl< T >::assignments, madness::FutureImpl< T >::callbacks, and MADNESS_ASSERT.

Referenced by madness::FutureImpl< T >::set(), madness::FutureImpl< T >::set(), and madness::FutureImpl< T >::set_handler().

◆ set_handler()

template<typename T >

static void madness::FutureImpl< T >::set_handler ( const AmArg & arg )

inlinestaticprivate

AM handler for remote set operations.

Todo:: Description needed.

Parameters

[in] arg Description needed.

References madness::World::am, madness::arg(), fred(), madness::RemoteReference< T >::get(), madness::new_am_arg(), madness::FutureImpl< T >::remote_ref, madness::RemoteReference< T >::reset(), madness::WorldAmInterface::send(), madness::FutureImpl< T >::set_assigned(), T(), and madness::FutureImpl< T >::t.

Friends And Related Symbol Documentation

◆ Future< T >

template<typename T >

friend class Future< T >

friend

◆ operator<<

template<typename T >

std::ostream & operator<<	(	std::ostream &	out,
		const Future< T > &	f
	)

friend

Human readable printing of a Future to a stream.

Stream output operator for a future.

Template Parameters

T	The type of future.

Parameters

[in,out]	out	The output stream.
[in]	f	The future.

Returns: The output stream.

Todo:: Brief description needed.

Todo:: Descriptions needed.

Template Parameters

T	Description needed.

Parameters

[in,out]	The	output stream.
[in]	f	The future to be output.

Returns: The output stream.

Member Data Documentation

◆ assigned

template<typename T >

std::atomic<bool> madness::FutureImpl< T >::assigned

private

A flag indicating if the future has been set.

Referenced by madness::FutureImpl< T >::~FutureImpl(), madness::FutureImpl< T >::add_to_assignments(), madness::FutureImpl< T >::probe(), madness::FutureImpl< T >::register_callback(), and madness::FutureImpl< T >::set_assigned().

◆ assignments

template<typename T >

volatile assignmentT madness::FutureImpl< T >::assignments

mutableprivate

A stack that stores future objects that are set to the same value as this future, once it has been set.

Referenced by madness::FutureImpl< T >::~FutureImpl(), madness::FutureImpl< T >::add_to_assignments(), and madness::FutureImpl< T >::set_assigned().

◆ callbacks

template<typename T >

volatile callbackT madness::FutureImpl< T >::callbacks

private

A stack that stores callbacks that are invoked once the future has been assigned.

Referenced by madness::FutureImpl< T >::~FutureImpl(), madness::FutureImpl< T >::register_callback(), and madness::FutureImpl< T >::set_assigned().

◆ MAXCALLBACKS

template<typename T >

const int madness::FutureImpl< T >::MAXCALLBACKS = 4

staticprivate

The static stack size used for callbacks and future assignment used for small stack size optimizations.

◆ remote_ref

template<typename T >

RemoteReference< FutureImpl<T> > madness::FutureImpl< T >::remote_ref

private

Reference to a remote future pimpl.

Referenced by madness::FutureImpl< T >::get(), madness::FutureImpl< T >::get(), madness::FutureImpl< T >::is_local(), madness::FutureImpl< T >::set(), madness::FutureImpl< T >::set(), and madness::FutureImpl< T >::set_handler().

◆ t

template<typename T >

volatile T madness::FutureImpl< T >::t

private

The future data.

Referenced by madness::FutureImpl< T >::add_to_assignments(), madness::FutureImpl< T >::get(), madness::FutureImpl< T >::get(), madness::FutureImpl< T >::set(), madness::FutureImpl< T >::set(), and madness::FutureImpl< T >::set_handler().

The documentation for this class was generated from the following file:

future.h

Public Member Functions

Private Types

Private Member Functions

Static Private Member Functions

Private Attributes

Static Private Attributes

Friends

Detailed Description

Member Typedef Documentation

◆ assignmentT

◆ callbackT

Constructor & Destructor Documentation

◆ FutureImpl() [1/2]

◆ FutureImpl() [2/2]

◆ ~FutureImpl()

Member Function Documentation

◆ add_to_assignments()

◆ get() [1/2]

◆ get() [2/2]

◆ is_local()

◆ probe()

◆ register_callback()

◆ replace_with()

◆ set() [1/2]

◆ set() [2/2]

◆ set_assigned()

◆ set_handler()

Friends And Related Symbol Documentation

◆ Future< T >

◆ operator<<

Member Data Documentation

◆ assigned

◆ assignments

◆ callbacks

◆ MAXCALLBACKS

◆ remote_ref

◆ t