11 << 1 = $2
21 << 32 = $0
31 << 9001 = $0
4-1 << 1 = $FFFFFFFE
5-1 << 32 = $0
6-1 << -9001 = $FFFFFFFF
7-1 >> 1 = $FFFFFFFF
8-1 >> 32 = $FFFFFFFF
9-1 >> 9001 = $FFFFFFFF
10-4 >> 1 = $FFFFFFFE
11-4 >> 2 = $FFFFFFFF
12-1 >> -9001 = $0
13