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Communications Union

In many cases, communication required for two different operands can be replaced by their union. Clearly, the advantage of communication union is that it reduces the number of communication statements and thus the number of messages. For example, the following code may require two overlapping_shifts. However, with simple analysis, the compiler can eliminate the shift of size 2.


         FORALL(I=1:N) A(I)=B(I+2)+B(I+3)

The communication union optimization can be applied in a statement as well as inter statement. The compiler needs data-flow analysis infra-structure to perform inter statements communication union.


zbozkus@
Thu Jul 6 21:09:19 EDT 1995