Iirc, the interpreter recognizes common idioms (sequences of 2-4 operations) and has optimized fused implementations for those idioms that avoid intermediate results.

It can also avoid creating intermediate results for quite a few operations, because for example reverse, transpose, etc only change how the arrays are traversed (order in which elements are accessed). You can reuse the original data and change the indexing information. That’s known as beating and dragging.