Avoid direct-CXs in RZX calibration pass

qiskit/transpiler/passes/calibration/__init__.py

@@ -12,4 +12,5 @@
 
 """Module containing transpiler calibration passes."""
 
-from .builders import RZXCalibrationBuilder, RZXCalibrationBuilderNoEcho, PulseGates
+from .pulse_gate import PulseGates
+from .rzx_builder import RZXCalibrationBuilder, RZXCalibrationBuilderNoEcho

qiskit/transpiler/passes/calibration/base_builder.py

@@ -0,0 +1,80 @@
+# This code is part of Qiskit.
+#
+# (C) Copyright IBM 2022.
+#
+# This code is licensed under the Apache License, Version 2.0. You may
+# obtain a copy of this license in the LICENSE.txt file in the root directory
+# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.
+#
+# Any modifications or derivative works of this code must retain this
+# copyright notice, and modified files need to carry a notice indicating
+# that they have been altered from the originals.
+
+"""Calibration builder base class."""
+
+from abc import abstractmethod
+from typing import List, Union
+
+from qiskit.circuit import Instruction as CircuitInst
+from qiskit.dagcircuit import DAGCircuit
+from qiskit.pulse import Schedule, ScheduleBlock
+from qiskit.pulse.instruction_schedule_map import CalibrationPublisher
+from qiskit.transpiler.basepasses import TransformationPass
+
+from .exceptions import CalibrationNotAvailable
+
+
+class CalibrationBuilder(TransformationPass):
+    """Abstract base class to inject calibrations into circuits."""
+
+    @abstractmethod
+    def supported(self, node_op: CircuitInst, qubits: List) -> bool:
+        """Determine if a given node supports the calibration.
+
+        Args:
+            node_op: Target instruction object.
+            qubits: Integer qubit indices to check.
+
+        Returns:
+            Return ``True`` is calibration can be provided.
+        """
+
+    @abstractmethod
+    def get_calibration(self, node_op: CircuitInst, qubits: List) -> Union[Schedule, ScheduleBlock]:
+        """Gets the calibrated schedule for the given instruction and qubits.
+
+        Args:
+            node_op: Target instruction object.
+            qubits: Integer qubit indices to check.
+
+        Returns:
+            Return Schedule of target gate instruction.
+        """
+
+    def run(self, dag: DAGCircuit) -> DAGCircuit:
+        """Run the calibration adder pass on `dag`.
+
+        Args:
+            dag: DAG to schedule.
+
+        Returns:
+            A DAG with calibrations added to it.
+        """
+        qubit_map = {qubit: i for i, qubit in enumerate(dag.qubits)}
+        for node in dag.gate_nodes():
+            qubits = [qubit_map[q] for q in node.qargs]
+
+            if self.supported(node.op, qubits) and not dag.has_calibration_for(node):
+                # calibration can be provided and no user-defined calibration is already provided
+                try:
+                    schedule = self.get_calibration(node.op, qubits)
+                except CalibrationNotAvailable:
+                    # Fail in schedule generation. Just ignore.
+                    continue
+                publisher = schedule.metadata.get("publisher", CalibrationPublisher.QISKIT)
+
+                # add calibration if it is not backend default
+                if publisher != CalibrationPublisher.BACKEND_PROVIDER:
+                    dag.add_calibration(gate=node.op, qubits=qubits, schedule=schedule)
+
+        return dag