tf::BoundedTaskQueue class

class to create a lock-free bounded single-producer multiple-consumer queue

Template parameters
T	data type
LogSize	the base-2 logarithm of the queue size

This class implements the work-stealing queue described in the paper, "Correct and Efficient Work-Stealing for Weak Memory Models," available at https://www.di.ens.fr/~zappa/readings/ppopp13.pdf.

Only the queue owner can perform pop and push operations, while others can steal data from the queue.

Constructors, destructors, conversion operators

auto empty() const -> bool noexcept: queries if the queue is empty at the time of this call
auto size() const -> size_t noexcept: queries the number of items at the time of this call
auto capacity() const -> size_t constexpr: queries the capacity of the queue
template<typename O> auto try_push(O&& item) -> bool: tries to insert an item to the queue
template<typename O, typename C> void push(O&& item, C&& on_full): tries to insert an item to the queue or invoke the callable if fails
auto pop() -> T: pops out an item from the queue
auto steal() -> T: steals an item from the queue

tries to insert an item to the queue

Template parameters
O	data type
Parameters
item	the item to perfect-forward to the queue
Returns	`true` if the insertion succeed or `false` (queue is full)

Only the owner thread can insert an item to the queue.

tries to insert an item to the queue or invoke the callable if fails

Template parameters
O	data type
C	callable type
Parameters
item	the item to perfect-forward to the queue
on_full	callable to invoke when the queue is faull (insertion fails)

Only the owner thread can insert an item to the queue.

pops out an item from the queue

Only the owner thread can pop out an item from the queue. The return can be a std::nullopt if this operation failed (empty queue).

steals an item from the queue

Any threads can try to steal an item from the queue. The return can be a std::nullopt if this operation failed (not necessary empty).