  Simon's algorithm was one of the first problems to demonstrate a genuine
quantum advantage. The algorithm, however, assumes access to noise-free qubits.
In our work we use Simon's algorithm to benchmark the error rates of devices
currently available in the "quantum cloud." As a main result we obtain an
objective comparison between the different physical platforms made available by
IBM and IonQ. Our study highlights the importance of understanding the device
architectures and chip topologies when transpiling quantum algorithms onto
hardware. For instance, we demonstrate that two-qubit operations on spatially
separated qubits on superconducting chips should be avoided.
