  SIMD||DNA is a model of DNA strand displacement allowing parallel in-memory
computation on DNA storage. We show how to simulate an arbitrary 3-symbol
space-bounded Turing machine with a SIMD||DNA program, giving a more direct and
efficient route to general-purpose information manipulation on DNA storage than
the Rule 110 simulation of [Wang, Chalk, Soloveichik, DNA 2019]. We also
develop software that can simulate SIMD||DNA programs and produce SVG figures.
