In Python, a list `l` of length `n` allows indexing with negative indices, `l[i]`. The only constraint is that `n + i` becomes positive. Code in `ResolveAxis` assumes the constraints and only checks it using a `DCHECK`. But the macro is a no-op in non-debug builds and that can result in reading from negative offsets (buffer underflows).
PiperOrigin-RevId: 332530683
Change-Id: I464e073fee618054ae3719a3679739007bb3f3bc