Transpiler crashes on IBM Brisbane

[glanzz]

Running the following circuit fails on IBM Brisbane backend specifically when optimization level set to 2 or more.

Python Version: 3.11.9 Qiskit Version: 1.2.1 Qiskit IBM Transpiler Version: 0.7.0

from qiskit import QuantumCircuit
from qiskit_ibm_transpiler.transpiler_service import TranspilerService

qc = QuantumCircuit(6)
qc.h(0)
qc.x(1)
qc.x(4)
qc.swap(1,3)
qc.ecr(5,4)
qc.cx(4,1)
qc.ccx(5,2,0)
qc.ccz(2,5,0)
qc.sxdg(1)
qc.sx(1)
qc.ccz(2,5,0)
qc.ccx(5,2,0)
qc.cx(4,1)
qc.ecr(5,4)
qc.swap(1,3)
qc.h(0)
qc.measure_all()

print(qc)

for j in range(1,4):
    cloud_transpiler_service = TranspilerService(
        backend_name="ibm_brisbane",
        ai="false",
        optimization_level=j,
    )
    transpiled_circuit = cloud_transpiler_service.run(qc)
    print(f" Passed optimization level {j}")

Transpilation will be successful for optimization level 1 but fails for optimization level 2 or more with the following error:

        ┌───┐             ┌───┐                    ┌───┐┌───┐         ░ ┌─┐               
   q_0: ┤ H ├─────────────┤ X ├─■────────────────■─┤ X ├┤ H ├─────────░─┤M├───────────────
        ├───┤        ┌───┐└─┬─┘ │ ┌──────┐┌────┐ │ └─┬─┘├───┤         ░ └╥┘┌─┐            
   q_1: ┤ X ├───X────┤ X ├──┼───┼─┤ √Xdg ├┤ √X ├─┼───┼──┤ X ├───X─────░──╫─┤M├────────────
        └───┘   │    └─┬─┘  │   │ └──────┘└────┘ │   │  └─┬─┘   │     ░  ║ └╥┘┌─┐         
   q_2: ────────┼──────┼────■───■────────────────■───■────┼─────┼─────░──╫──╫─┤M├─────────
                │      │    │   │                │   │    │     │     ░  ║  ║ └╥┘┌─┐      
   q_3: ────────X──────┼────┼───┼────────────────┼───┼────┼─────X─────░──╫──╫──╫─┤M├──────
        ┌───┐┌──────┐  │    │   │                │   │    │  ┌──────┐ ░  ║  ║  ║ └╥┘┌─┐   
   q_4: ┤ X ├┤1     ├──■────┼───┼────────────────┼───┼────■──┤1     ├─░──╫──╫──╫──╫─┤M├───
        └───┘│  Ecr │       │   │                │   │       │  Ecr │ ░  ║  ║  ║  ║ └╥┘┌─┐
   q_5: ─────┤0     ├───────■───■────────────────■───■───────┤0     ├─░──╫──╫──╫──╫──╫─┤M├
             └──────┘                                        └──────┘ ░  ║  ║  ║  ║  ║ └╥┘
meas: 6/═════════════════════════════════════════════════════════════════╩══╩══╩══╩══╩══╩═
                                                                         0  1  2  3  4  5 
 Passed opt level 1

ERROR:qiskit_ibm_transpiler.wrappers.transpile:Error transforming the result to a QuantumCircuit object
Traceback (most recent call last):
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit_ibm_transpiler/utils.py", line 116, in get_circuit_from_qasm
    qasm2.loads(
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit/qasm2/__init__.py", line 587, in loads
    return _parse.from_bytecode(
           ^^^^^^^^^^^^^^^^^^^^^
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit/qasm2/parse.py", line 214, in from_bytecode
    for op in bc:
qiskit.qasm2.exceptions.QASM2ParseError: "<input>:1,4396: 'rzx_140108262515216_140109994476304' is not defined in this scope"

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit/qasm3/__init__.py", line 342, in loads
    return qiskit_qasm3_import.parse(program)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit_qasm3_import/api.py", line 27, in parse
    return convert(openqasm3.parse(string))
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit_qasm3_import/api.py", line 21, in convert
    return ConvertVisitor().convert(node).circuit
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit_qasm3_import/converter.py", line 147, in convert
    state: State = self.visit(node, State(source))
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/openqasm3/visitor.py", line 44, in visit
    return visitor(node, context)
           ^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit_qasm3_import/converter.py", line 288, in visit_Program
    context = self.visit(statement, context)
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/openqasm3/visitor.py", line 44, in visit
    return visitor(node, context)
           ^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit_qasm3_import/converter.py", line 293, in visit_Include
    raise_from_node(node, "non-stdgates imports not currently supported")
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit_qasm3_import/exceptions.py", line 31, in raise_from_node
    raise ConversionError(message, node)
qiskit_qasm3_import.exceptions.ConversionError: 1,14: non-stdgates imports not currently supported

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/Users/***/scripts/mycircuit.py", line 51, in <module>
    transpiled_circuit = cloud_transpiler_service.run(qc)
                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit_ibm_transpiler/transpiler_service.py", line 111, in run
    transpile_result = self.transpiler_service.transpile(
                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit_ibm_transpiler/wrappers/transpile.py", line 90, in transpile
    transpiled_circuits.append(_get_circuit_from_result(res, orig_circ))
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit_ibm_transpiler/wrappers/transpile.py", line 103, in _get_circuit_from_result
    transpiled_circuit = get_circuit_from_qasm(transpile_resp["qasm"])
                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit_ibm_transpiler/utils.py", line 122, in get_circuit_from_qasm
    return get_circuit_from_qasm.fix_ecr(qasm3.loads(qasm_string))
                                         ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit/utils/lazy_tester.py", line 149, in out
    return function(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/***/scripts/qiskit1.2.1/lib/python3.11/site-packages/qiskit/qasm3/__init__.py", line 344, in loads
    raise QASM3ImporterError(str(exc)) from exc
qiskit.qasm3.exceptions.QASM3ImporterError: '1,14: non-stdgates imports not currently supported'

[y4izus]

Thank you @glanzz for submitting the issue. Some of our team members are trying to reproduce the error, but we are not able to do it. Could you check if it's still happening for you? Thank you!

[glanzz]

I was able to reproduce it multiple times yesterday, seems like the issue is fixed.

[y4izus]

So, it's now working for you too, right?? if you agree, I'm gonna close the issue :)

[glanzz]

@y4izus I am able to reproduce the issue today !

[glanzz]

Seems like the QASM response from cloud transpiler is sending rzx gate. And the conversion from QASM to QuantumCircuit obejct is failing when there is rzx gate in it.

[victor-villar]

Hi @glanzz ! Thanks for reporting again, I have been able to reproduce now, but with ai=true instead of ai=false. Can you confirm if this is the case for you as well? Is it also happening with ai=false?

[glanzz]

Yes, I am able to reproduce with ai=True as well as ai=False.