code: private void hashMix() {
         a = subtract(a, b); a = subtract(a, c); a = xor(a, c >> 13);
         b = subtract(b, c); b = subtract(b, a); b = xor(b, leftShift(a, 8));
         c = subtract(c, a); c = subtract(c, b); c = xor(c, (b >> 13));
         a = subtract(a, b); a = subtract(a, c); a = xor(a, (c >> 12));
         b = subtract(b, c); b = subtract(b, a); b = xor(b, leftShift(a, 16));
         c = subtract(c, a); c = subtract(c, b); c = xor(c, (b >> 5));
         a = subtract(a, b); a = subtract(a, c); a = xor(a, (c >> 3));
         b = subtract(b, c); b = subtract(b, a); b = xor(b, leftShift(a, 10));
         c = subtract(c, a); c = subtract(c, b); c = xor(c, (b >> 15));
       }
docs: Mix up the values in the hash function.