iverilog/ivtest/gold/sdf7.gold

                   0 A=x, B=x, Q=x
                  10 A=1, B=1, Q=x
                  13 A=1, B=1, Q=0
                  20 A=1, B=0, Q=0
                  21 A=1, B=0, Q=1
                  30 A=1, B=1, Q=1
                  33 A=1, B=1, Q=0
                  40 A=0, B=1, Q=0
                  41 A=0, B=1, Q=1