Question

SystemVerilog allows tasks to be called from a foreign language, similar to functions. Such tasks are termed “exported tasks”.

All aspects of exported functions described above in Section 27.6 apply to exported tasks. This includes legal declaration scopes as well as usage of the optional c_identifier.

It is never legal to call an exported task from within an imported function. These semantics are identical to native SystemVerilog semantics, in which it is illegal for a function to perform a task enable.

It is legal for an imported task to call an exported task only if the imported task is declared with the context property. Section 27.4.3 (Context tasks and functions) for more details.

One difference between exported tasks and exported functions is that SystemVerilog tasks do not have return value types. The return value of an exported task is an int value which indicates if a disable is active or not on the current execution thread.

Similarly, imported tasks return an int value which is used to indicate that the imported task has acknowledged a disable. See Section 27.8 for more detail on disables in DPI.