13.2  device Clause

Arguments

Modifiers

Directives

Semantics

If device_num is specified as the device-modifier, the device-description specifies the device number of the target device. If device-modifier does not appear in the clause, the behavior of the clause is as if device-modifier is device_num. If the device-description evaluates to omp_invalid_device, runtime error termination is performed.

If ancestor is specified as the device-modifier, the device-description specifies the number of target nesting level of the target device. Specifically, if the device-description evaluates to 1, the target device is the parent device of the enclosing target region. If the construct on which the device clause appears is not encountered in a target region, the current device is treated as the parent device.

Unless otherwise specified, for directives that accept the device clause, if no device clause is present, the behavior is as if the device clause appears without a device-modifier and with a device-description that evaluates to the value of the default-device-var ICV.

Restrictions

• The ancestor device-modifier must not appear on the device clause on any directive other than the target construct.
• If the ancestor device-modifier is specified, the device-description must evaluate to 1 and a requires directive with the reverse_offload clause must be specified;
• If the device_num device-modifier is specified and target-offload-var is not mandatory, device-description must evaluate to a conforming device number.

Cross References

• dispatch directive, see Section 7.6
• interop directive, see Section 14.1
• target data directive, see Section 13.5
• target directive, see Section 13.8
• target enter data directive, see Section 13.6
• target exit data directive, see Section 13.7
• target update directive, see Section 13.9
• target-offload-var ICV, see Section 2.1