26
Compiling ZPL Programs
•ZPL uses a “single
program, multiple data” (SPMD) view Þ compiler produces 1 program
•Logically, ZPL
executes 1 statement at a time, but processors go
at their own rate using “data synchronization”
for i := 1
to n do
[1..m,*]
Col := >>[ ,k] A; -- Flood kth col of A
[*,1..p]
Row := >>[k, ] B; -- Flood kth row of B
[1..m,1..p] C += Col*Row; -- Combine elements
end;
bdcst col;
bdcst row;
compute;
bdcst col;
recv row;
compute;
recv col;
recv row;
compute;
recv col;
bdcst row;
compute;
