Rate    regex    split unpack_C unpack_a
regex    3.00/s       --      -3%      -9%     -19%
split    3.09/s       3%       --      -6%     -17%
unpack_C 3.29/s      10%       7%       --     -11%
unpack_a 3.71/s      24%      20%      13%       --