inline future<HostIterator> copy_to_host_async(DeviceIterator first,
DeviceIterator last,
HostIterator result,
command_queue &queue)
{
typedef typename
std::iterator_traits<DeviceIterator>::value_type
value_type;
size_t count = iterator_range_size(first, last);
if(count == 0){
return future<HostIterator>();
}
const buffer &buffer = first.get_buffer();
size_t offset = first.get_index();
event event_ =
queue.enqueue_read_buffer_async(buffer,
offset * sizeof(value_type),
count * sizeof(value_type),
::boost::addressof(*result));
return make_future(iterator_plus_distance(result, count), event_);
}
inline future<HostIterator> copy_to_host_async(svm_ptr<T> first,
svm_ptr<T> last,
HostIterator result,
command_queue &queue)
{
size_t count = iterator_range_size(first, last);
if(count == 0){
return result;
}
event event_ = queue.enqueue_svm_memcpy_async(
::boost::addressof(*result), first.get(), count * sizeof(T)
);
return make_future(iterator_plus_distance(result, count), event_);
}