AASRouting doesn't work for circuits with non-default register names.

[IlanIwumbwe]

Benny and I found this by running a randomly generated circuit through the compiler

Related to this and this.

subcirc_4 = Circuit(2, 2, "subcirc_4")
subcirc_4.add_q_register("qreg", 1)
subcirc_4.measure_all()
AASRouting(RingArch(subcirc_4.n_qubits)).apply(subcirc_4)

Results in:

----> 7 AASRouting(RingArch(subcirc_4.n_qubits)).apply(subcirc_4)
      9 draw(subcirc_4)

RuntimeError: Circuit does not contain unit with id: q[2]

[cqc-alec]

Looks like this is a direct result of #1418 , because the AASRouting pass performs ComposePhasePolyBoxes as its first step.

[IlanIwumbwe]

Right, thanks