| Name | Value | Comment |
|---|
| allocation_lifetime | 0 | Dependency between an alloc / free instruction and the first / last access front on that allocation |
| write_to_allocation | 1 | An anti- or output dependency on data present in an allocation |
| read_from_allocation | 2 | True dataflow dependency on data present in an allocation |
| side_effect | 3 | Dependency between two host tasks that affect the same host object, or between such a host task and `destroy_host_object_instruction` |
| collective_group_order | 4 | Serializing dependency between two host tasks that participate in the same `collective_group` |
| last_epoch | 5 | Fall-back dependency to the effective epoch for instructions that have no other dependency |
| execution_front | 6 | Dependency from a new epoch- or horizon instruction to the previous execution front |
| split_receive | 7 | Ordering dependency between a `split_receive_instruction` and its `await_receive_instruction`s |