Fastest way of contracting arrays

General Usage Performance
,
2

A, B, and D are currently globals. If you pass them into the function like

d = 10
A=randn(d,d,d,d,d)
B=randn(d,d,d,d,d)
function funza(A, B, d)
    acc = 0.0
    for i = 1:1:d, j= 1:1:d, k= 1:1:d, l= 1:1:d, m = 1:1:d
        acc += A[i,1,1,1,1]*A[l,1,1,1,1]*A[k,1,1,1,1]*A[j,1,1,1,1]*A[m,1,1,1,1]*B[m,l,k,j,i]
    end
    return acc
end
@time funza(A,B,d)

it takes 370μs

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