[UnitaryHack] Enable qiskit transpilation discontinous qubit indices

qiskit_braket_provider/providers/adapter.py

@@ -293,6 +293,54 @@ def aws_device_to_target(device: AwsDevice) -> Target:
                                 instruction_props[(dst, src)] = None
                 # building coupling map for device with connectivity graph
                 else:
+                    if isinstance(properties, RigettiDeviceCapabilities):
+
+                        def convert_continuous_qubit_indices(
+                            connectivity_graph: dict,
+                        ) -> dict:
+                            """Aspen qubit indices are discontinuous (label between x0 and x7, x being
+                            the number of the octagon) while the Qiskit transpiler creates and/or
+                            handles coupling maps with continuous indices. This function converts the
+                            discontinous connectivity graph from Aspen to a continuous one.
+
+                            Args:
+                                connectivity_graph (dict): connectivity graph from Aspen. For example
+                                4 qubit system, the connectivity graph will be:
+                                    {"0": ["1", "2", "7"], "1": ["0","2","7"], "2": ["0","1","7"],
+                                    "7": ["0","1","2"]}
+
+                            Returns:
+                                dict: Connectivity graph with continuous indices. For example for an
+                                input connectivity graph with discontinuous indices (qubit 0, 1, 2 and
+                                then qubit 7) as shown here:
+                                    {"0": ["1", "2", "7"], "1": ["0","2","7"], "2": ["0","1","7"],
+                                    "7": ["0","1","2"]}
+                                the qubit index 7 will be mapped to qubit index 3 for the qiskit
+                                transpilation step. Thereby the resultant continous qubit indices
+                                output will be:
+                                    {"0": ["1", "2", "3"], "1": ["0","2","3"], "2": ["0","1","3"],
+                                    "3": ["0","1","2"]}
+                            """
+                            # Creates list of existing qubit indices which are discontinuous.
+                            indices = [int(key) for key in connectivity_graph.keys()]
+                            indices.sort()
+                            # Creates a list of continuous indices for number of qubits.
+                            map_list = list(range(len(indices)))
+                            # Creates a dictionary to remap the discountinous indices to continuous.
+                            mapper = dict(zip(indices, map_list))
+                            # Performs the remapping from the discontinous to the continuous indices.
+                            continous_connectivity_graph = {
+                                mapper[int(k)]: [mapper[int(v)] for v in val]
+                                for k, val in connectivity_graph.items()
+                            }
+                            return continous_connectivity_graph
+
+                        connectivity.connectivityGraph = (
+                            convert_continuous_qubit_indices(
+                                connectivity.connectivityGraph
+                            )
+                        )
+
                     for src, connections in connectivity.connectivityGraph.items():
                         for dst in connections:
                             instruction_props[(int(src), int(dst))] = None

tests/providers/mocks.py

@@ -1,6 +1,8 @@
 """Mocks for testing."""
 
 from collections import Counter
+import copy
+from typing import Dict
 
 import uuid
 import numpy as np
@@ -12,6 +14,7 @@
 
 
 RIGETTI_ARN = "arn:aws:braket:::device/qpu/rigetti/Aspen-10"
+RIGETTI_ASPEN_ARN = "arn:aws:braket:::device/qpu/rigetti/Aspen-M-3"
 SV1_ARN = "arn:aws:braket:::device/quantum-simulator/amazon/sv1"
 TN1_ARN = "arn:aws:braket:::device/quantum-simulator/amazon/tn1"
 RIGETTI_REGION = "us-west-1"
@@ -64,6 +67,34 @@
     "deviceCapabilities": RIGETTI_MOCK_GATE_MODEL_QPU_CAPABILITIES.json(),
 }
 
+RIGETTI_MOCK_M_3_QPU_CAPABILITIES_JSON: Dict = copy.deepcopy(
+    RIGETTI_MOCK_GATE_MODEL_QPU_CAPABILITIES_JSON
+)
+RIGETTI_MOCK_M_3_QPU_CAPABILITIES_JSON["action"]["braket.ir.openqasm.program"][
+    "supportedOperations"
+] = ["RX", "RZ", "CP", "CZ", "XY"]
+RIGETTI_MOCK_M_3_QPU_CAPABILITIES_JSON["paradigm"]["qubitCount"] = 4
+RIGETTI_MOCK_M_3_QPU_CAPABILITIES_JSON["paradigm"]["connectivity"][
+    "connectivityGraph"
+] = {
+    "0": ["1", "2", "7"],
+    "1": ["0", "2", "7"],
+    "2": ["0", "1", "7"],
+    "7": ["0", "1", "2"],
+}
+RIGETTI_MOCK_M_3_QPU_CAPABILITIES = RigettiDeviceCapabilities.parse_obj(
+    RIGETTI_MOCK_M_3_QPU_CAPABILITIES_JSON
+)
+
+MOCK_RIGETTI_GATE_MODEL_M_3_QPU = {
+    "deviceName": "Aspen-M-3",
+    "deviceType": "QPU",
+    "providerName": "provider1",
+    "deviceStatus": "ONLINE",
+    "deviceArn": RIGETTI_ASPEN_ARN,
+    "deviceCapabilities": RIGETTI_MOCK_M_3_QPU_CAPABILITIES.json(),
+}
+
 MOCK_GATE_MODEL_SIMULATOR_CAPABILITIES_JSON = {
     "braketSchemaHeader": {
         "name": "braket.device_schema.simulators.gate_model_simulator_device_capabilities",

tests/providers/test_braket_provider.py

@@ -1,12 +1,12 @@
 """Tests for AWS Braket provider."""
 import unittest
 from unittest import TestCase
-from unittest.mock import Mock
+from unittest.mock import Mock, patch
 
 from braket.aws import AwsDeviceType
-from qiskit import transpile
+from qiskit import circuit as qiskit_circuit
 from qiskit.circuit.random import random_circuit
-
+from qiskit.compiler import transpile
 from qiskit_braket_provider.providers import AWSBraketProvider
 from qiskit_braket_provider.providers.braket_backend import (
     BraketBackend,
@@ -15,6 +15,8 @@
 from tests.providers.mocks import (
     MOCK_GATE_MODEL_SIMULATOR_SV,
     MOCK_GATE_MODEL_SIMULATOR_TN,
+    MOCK_RIGETTI_GATE_MODEL_M_3_QPU,
+    RIGETTI_MOCK_M_3_QPU_CAPABILITIES,
     SIMULATOR_REGION,
 )
 
@@ -69,3 +71,33 @@ def test_real_device_circuit_execution(self):
         )
         result = state_vector_backend.run(transpiled_circuit, shots=10)
         self.assertTrue(result)
+
+    @patch("braket.aws.aws_device.AwsDevice.get_devices")
+    def test_discontinous_qubit_indices_qiskit_transpilation(self, mock_get_devices):
+        """Tests circuit transpilation with discontinous qubit indices."""
+
+        mock_m_3_device = Mock()
+        mock_m_3_device.name = MOCK_RIGETTI_GATE_MODEL_M_3_QPU["deviceName"]
+        mock_m_3_device.arn = MOCK_RIGETTI_GATE_MODEL_M_3_QPU["deviceArn"]
+        mock_m_3_device.provider = MOCK_RIGETTI_GATE_MODEL_M_3_QPU["providerName"]
+        mock_m_3_device.status = MOCK_RIGETTI_GATE_MODEL_M_3_QPU["deviceStatus"]
+        mock_m_3_device.device_type = MOCK_RIGETTI_GATE_MODEL_M_3_QPU["deviceType"]
+        mock_m_3_device.device_capabilities = MOCK_RIGETTI_GATE_MODEL_M_3_QPU[
+            "deviceCapabilities"
+        ]
+        mock_m_3_device_properties = RIGETTI_MOCK_M_3_QPU_CAPABILITIES
+        mock_m_3_device_properties.service = Mock()
+        mock_m_3_device_properties.service.updatedAt = "2023-06-02T17:00:00+00:00"
+        mock_m_3_device.properties = mock_m_3_device_properties
+        mock_get_devices.return_value = [mock_m_3_device]
+
+        provider = AWSBraketProvider()
+        device = provider.get_backend("Aspen-M-3")
+
+        circ = qiskit_circuit.QuantumCircuit(3)
+        circ.h(0)
+        circ.cx(0, 1)
+        circ.cx(1, 2)
+
+        result = transpile(circ, device)
+        self.assertTrue(result)