notes.txt

The program looks like this:

  bst 4: 2411751540550330 - 64854237,0,0
  bxl 1: 2411751540550330 - 64854237,5,0
  cdv 5: 2411751540550330 - 64854237,4,0
  bxl 5: 2411751540550330 - 64854237,4,4053389
  bxc 0: 2411751540550330 - 64854237,1,4053389
  out 5: 2411751540550330 - 64854237,4053388,4053389
  adv 3: 2411751540550330 - 64854237,4053388,4053389
  jnz 0: 2411751540550330 - 8106779,4053388,4053389
  (repeat from top...)

In pseudocode:

  do {
    B = A & 0b111;
    B ^= 1 (= 0b001);
    C = A / (1 << B);
    B ^= 5 (= 0b101);
    B ^= C;
    output(B & 0b111);
    A /= (1 << 3);
  } while (A > 0);

We can simplify this to:

  do {
    B = (A & 0b111) ^ 0b001;
    C = A >> B;
    B ^= C ^ 0b101;
    output(B & 0b111);
    A >>= 3;
  } while (A > 0);

Simplified even further:

  do {
    B = (A & 0b111) ^ 0b001;
    B ^= (A >> B) ^ 0b101;
    output(B & 0b111);
    A >>= 3;
  } while (A > 0);

And even further, using a new constant `L` for better readability:

  do {
    L = A & 0b111;
    output((L ^ 0b100 ^ (A >> (L ^ 0b001))) & 0b111);
    A >>= 3;
  } while (A > 0);