Implement batching

[b0noI]

[b0noI]

w = [1, 2]
is = [2, 2]

[1, 2] * [2, = 1 * 2 + 2 * 2 = 6
2]

(1, 2) => (1, 2, 2)
[1, 2] * [ [2, 2], => [ [1, 2], * [[2, 2],
[3, 3] ] [1, 2] ] [3, 3]]