EE382C Embedded Software Systems - Projection
We can define a projection of a schedule onto a set of actors, such
as projection( (2(2B)(5A)), {A, C} ) = (2(5A)).
Computing the projection is as simple as removing the actors in
the schedule that are not in the list of actors in the projection
and deleting the null schedules in the modified schedule.
If S and S' are valid looped schedules for an
SDF graph G, e is an edge in G, and
i is a positive integer such that
1 <= i <= inv(snk(e), S),
- P(e, i, S) = P(e, i, S') <===>
T(e, i, S) = T(e, i, S'),
- P(e, i, S) = P(e, i, projection(S, {src(e), snk(e)}), and
- max_tokens(e, S) = max({T(e, k, S) | 1 < k < inv(snk(e), S)})
where
- T(e, i, S) denotes the number of tokens on edge e just
prior to the ith invocation of snk(e) in S, and
- P(e, i, S) denotes the number of invocations on src(e)
that precede the ith invocation of snk(e) in S.
Note that inv(A, S) means the number of times that schedule
S invokes actor A.
Updated 04/19/04.