It's a NULL / 'do not care' issue. 0 isn't a reserved out of band value, it's payload data and anything beyond the bounds should have been DNC. It's possible

It's a NULL / 'do not care' issue. 0 isn't a reserved out of band value, it's payload data and anything beyond the bounds should have been DNC. It's possible some other result, likely aligned to an easy binary multiple would still produce a square block of 2, and that allowing the far edges to float to some other value could yield a slightly more compact logic array. Back-filling the entire side to the clamped upper value doesn't cost that much more though, and is known to solve the issue. As pointed out elsewhere, that sort of solution would also be faster for engineering time, fit within the planned space budget, and best of all reduces conative load. It's obviously correct when looking at the bug.