132
A. Tabuchi et al.
Fig. 8 XACC code with coarray
Fig. 9 XACC code with devices directive
2.5.1 devices Directive
The devices directive declares a device array that corresponds to a device set.
This directive is analogous to the nodes directive for nodes in XMP.
Example
Figure 9 is an example of declaring devices. The device array d corresponds to a set
of entire default devices, and e is a subset of the predefined device array nvidia.
The program must be executed by a node which is equipped with four or more
NVIDIA accelerator devices.
2.5.2 on_device Clause
The on_device clause in a directive specifies a device set that the directive targets.
The on_device clause may appear on parallel, parallel loop,
kernels, kernels loop, data, enter data, exit data, declare,
update, wait, and barrier_device directives.
The directive is applied to each device in the device set in parallel. If there is
no layout clause, the all devices process the directive for same data or work
redundantly.