message: Explicitly handle Tensors in start & stop
  The current check was doing a identity check in order to handle both
  tensors and integers. This becomes problematic when enabling tensor
  equality. Instead we explicitly check for Tensor type and only compare
  with sys.maxsize for non-Tensors.
diff: @@ -704,13 +704,15 @@ def _slice_helper(tensor, slice_spec, var=None):
  # python doesn't always use None when constructing ranges
  # for example a[:] gives slice(None,sys.maxsize,None)
  # whereas a[::1] gives slice(None,None,None)
  - if s.start is not None and s.start is not sys.maxsize:
  + if s.start is not None and (isinstance(s.start, ops.Tensor) or
  + s.start != sys.maxsize):
  _check_index(s.start)
  begin.append(s.start)
  else:
  begin.append(0)
  begin_mask |= (1 << index)
  - if s.stop is not None and s.stop != sys.maxsize:
  + if s.stop is not None and (isinstance(s.stop, ops.Tensor) or
  + s.stop != sys.maxsize):
  _check_index(s.stop)
  end.append(s.stop)
  else:
  