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Now consider how to pipeline steps 1 and 2 of the SSA4 tracking algorithm. The problem
is to pipeline the step 2 computation right behind the computations of step 1. Note that the
~--outputs from step 1 are inputs to step 2. Hence step two can start execution as soon as
the ~-values become available. As soon as the cells
P(1)-P(r +
1) finish the computations
of Figure 1, they start executing step 2. To see how, write r as
r ---- X- Yl/~l -- Y2~2 --'''-- Vr-{-1/~r+l
(17)
where vj denotes the
jth
column of V. Here each of the terms in this expansion are
systolic streams that ...