pbitdiff
pbitdiff(val, prev_val, bits);
pbitdiff(val1, prev_val1, bits1);
pbitdiff(val2, prev_val2, bits2);
pbitdiff(val1, prev_val1, bits1);
pbitdiff(val2, prev_val2, bits2);
pbitdiff(val3, prev_val3, bits3);
pbitdiff(value, prev_value, bits);