Language Issues: Data Management
Break up large arrays into smaller sub-arrays to improve data locality (aka: cache blocking or tiling)
A[j,i] = A[j,i] + B[i,j];
A[j+1] = A[j+1,i]+B[i,j+1];
A([j,i+1] = A[j,i+1]+B[i+1,j];
A[j+1,i+1]=A[j+1,i+1]+B[i+1,j+1];