Summary
The targetenterdata directive specifies that variables are mapped to a device data environment.
The targetenterdata directive is a stand-alone directive.
Syntax
The syntax of the targetenterdata construct is as follows:
Binding
The binding task set for a targetenterdata region is the generating task, which is the target task
generated by the targetenterdata construct. The targetenterdata region binds to the
corresponding target task region.
Description
When a targetenterdata construct is encountered, the list items are mapped to the device data
environment according to the map clause semantics.
The targetenterdata construct is a task generating construct. The generated task is a target task.
The generated task region encloses the targetenterdata region.
All clauses are evaluated when the targetenterdata construct is encountered. The data environment
of the target task is created according to the data-mapping attribute clauses on the targetenterdata
construct, per-data environment ICVs, and any default data-sharing attribute rules that apply
to the targetenterdata construct. If a variable or part of a variable is mapped by the
targetenterdata construct, the variable has a default data-sharing attribute of shared in the data
environment of the target task.
Assignment operations associated with mapping a variable (see Section 2.21.7.1) occur when the target
task executes.
If the nowait clause is present, execution of the target task may be deferred. If the nowait clause is not
present, the target task is an included task.
If a depend clause is present, it is associated with the target task.
If no device clause is present, the behavior is as if the device clause appears with an expression equal to
the value of the default-device-var ICV.
When an if clause is present and the if clause expression evaluates to false, the target device is the
host.
Execution Model Events
Events associated with a target task are the same as for the task construct defined in Section 2.12.1.
The target-enter-data-begin event occurs when a thread enters a targetenterdata region.
The target-enter-data-end event occurs when a thread exits a targetenterdata region.
Tool Callbacks
Callbacks associated with events for target tasks are the same as for the task construct defined in
Section 2.12.1; (flags&ompt_task_target) always evaluates to true in the dispatched
callback.
A thread dispatches a registered ompt_callback_target or ompt_callback_target_emi
callback with ompt_scope_begin as its endpoint argument and ompt_target_enter_data or
ompt_target_enter_data_nowait if the nowait clause is present as its kind argument for
each occurrence of a target-enter-data-begin event in that thread in the context of the target
task on the host. Similarly, a thread dispatches a registered ompt_callback_target or
ompt_callback_target_emi callback with ompt_scope_end as its endpoint argument and
ompt_target_enter_data or ompt_target_enter_data_nowait if the nowait clause is
present as its kind argument for each occurrence of a target-enter-data-end event in that thread in the context
of the target task on the host. These callbacks have type signature ompt_callback_target_t or
ompt_callback_target_emi_t, respectively.
Restrictions
Restrictions to the targetenterdata construct are as follows:
A
program
must
not
depend
on
any
ordering
of
the
evaluations
of
the
clauses
of
the
targetenterdata
directive,
or
on
any
side
effects
of
the
evaluations
of
the
clauses.
At
least
one
map
clause
must
appear
on
the
directive.
At
most
one
device
clause
can
appear
on
the
directive.
The
device
clause
expression
must
evaluate
to
a
non-negative
integer
value
that
is
less
than
or
equal
to
the
value
of
omp_get_num_devices().
At
most
one
if
clause
can
appear
on
the
directive.
A
map-type
must
be
specified
in
all
map
clauses
and
must
be
either
to
or
alloc.
At
most
one
nowait
clause
can
appear
on
the
directive.