3.1.24. Nbor list use

Nbor lists are used for these purposes, in logical order

1. In list_t%check_ready() the nbor list is used to figure out if a task is ready to be updated, by comparing the states of tasks with the function task_t%is_ahead_of().

2. After the task gets picked from the ready queue, e.g. by dispatcher0_t%update, the nbor list is used by task_t%dnload to pick up the information from its nbors that it needs, in order to update.

3. After the task has updated, list_t%check_nbors() uses the nbor list to determine which nbor tasks to run list_t%check_ready() on.

   the nbor list of some task that depends on the active task is used to check if that task became ready to update after the current task updates. Such tasks are on the nbor list of the active task, and has a flag needs_me set.