InstructionDurations from BackendV2

qiskit/transpiler/instruction_durations.py

@@ -18,7 +18,7 @@
 from qiskit.circuit import Barrier, Delay
 from qiskit.circuit import Instruction, ParameterExpression
 from qiskit.circuit.duration import duration_in_dt
-from qiskit.providers import Backend
+from qiskit.providers import Backend, BackendV1, BackendV2
 from qiskit.transpiler.exceptions import TranspilerError
 from qiskit.utils.units import apply_prefix
 
@@ -71,30 +71,38 @@ def from_backend(cls, backend: Backend):
 
         Returns:
             InstructionDurations: The InstructionDurations constructed from backend.
-
-        Raises:
-            TranspilerError: If dt and dtm is different in the backend.
         """
+
         # All durations in seconds in gate_length
         instruction_durations = []
-        backend_properties = backend.properties()
-        if hasattr(backend_properties, "_gates"):
-            for gate, insts in backend_properties._gates.items():
-                for qubits, props in insts.items():
-                    if "gate_length" in props:
-                        gate_length = props["gate_length"][0]  # Throw away datetime at index 1
-                        instruction_durations.append((gate, qubits, gate_length, "s"))
-            for q, props in backend.properties()._qubits.items():
-                if "readout_length" in props:
-                    readout_length = props["readout_length"][0]  # Throw away datetime at index 1
-                    instruction_durations.append(("measure", [q], readout_length, "s"))
-
-        try:
-            dt = backend.configuration().dt
-        except AttributeError:
-            dt = None
-
-        return cls(instruction_durations, dt=dt)
+        return_durations = None
+
+        # Logic to handle if backend is sub-class of old BackendV1
+        if isinstance(backend, BackendV1):
+            backend_properties = backend.properties()
+            if hasattr(backend_properties, "_gates"):
+                for gate, insts in backend_properties._gates.items():
+                    for qubits, props in insts.items():
+                        if "gate_length" in props:
+                            gate_length = props["gate_length"][0]  # Ignore datetime at index 1
+                            instruction_durations.append((gate, qubits, gate_length, "s"))
+                for q, props in backend.properties()._qubits.items():
+                    if "readout_length" in props:
+                        readout_length = props["readout_length"][0]  # Ignore datetime at index 1
+                        instruction_durations.append(("measure", [q], readout_length, "s"))
+
+            try:
+                dt = backend.configuration().dt
+            except AttributeError:
+                dt = None
+
+            return_durations = cls(instruction_durations, dt=dt)
+
+        # Logic to handle if backend is sub-class is BackendV2
+        elif isinstance(backend, BackendV2):
+            return_durations = backend.target.durations()
+
+        return return_durations
 
     def update(self, inst_durations: "InstructionDurationsType" | None, dt: float = None):
         """Update self with inst_durations (inst_durations overwrite self).

releasenotes/notes/Add_support_for_BackendV2_in_instruction_durations_from_backend-9ce722879c870377.yaml

@@ -0,0 +1,22 @@
+---
+features:
+  - |
+    This enables the support for :class:`.BackendV2` in :meth:`.from_backend`
+    of :class:`.InstructionDurations`.
+
+    Users can have an object of :class:`.InstructionDurations` using :class:`.BackendV2`
+    from :meth:`.from_backend` with followig code.
+
+    .. code-block:: python
+
+      from qiskit.providers.fake_provider import FakePerth
+      from qiskit.transpiler import InstructionDurations
+      backendV2 = FakePerth()
+
+      inst_dur = InstructionDurations.from_backend(backendV2)
+
+upgrade:
+  - |
+    Given :code:`dt` and :code:`dtm` for a :class:`.BackendV1` or :class:`.BackendV2` are unequal,
+    :meth:`~.InstructionDurations.from_backend` does not raise any error.
+

test/python/transpiler/test_instruction_durations.py

@@ -13,17 +13,17 @@
 # pylint: disable=missing-function-docstring
 
 """Test InstructionDurations class."""
-
+from copy import deepcopy
 from qiskit.circuit import Delay, Parameter
-from qiskit.providers.fake_provider import FakeParis, FakeTokyo
+from qiskit.providers.fake_provider import FakeParis, FakePerth
 from qiskit.transpiler.exceptions import TranspilerError
 from qiskit.transpiler.instruction_durations import InstructionDurations
 
 from qiskit.test.base import QiskitTestCase
 
 
-class TestInstructionDurationsClass(QiskitTestCase):
-    """Test Test InstructionDurations class."""
+class TestInstructionDurations(QiskitTestCase):
+    """Test InstructionDurations class."""
 
     def test_empty(self):
         durations = InstructionDurations()
@@ -36,41 +36,13 @@ def test_fail_if_invalid_dict_is_supplied_when_construction(self):
         with self.assertRaises(TranspilerError):
             InstructionDurations(invalid_dic)
 
-    def test_from_backend_for_backend_with_dt(self):
-        backend = FakeParis()
-        gate = self._find_gate_with_length(backend)
-        durations = InstructionDurations.from_backend(backend)
-        self.assertGreater(durations.dt, 0)
-        self.assertGreater(durations.get(gate, 0), 0)
-
-    def test_from_backend_for_backend_without_dt(self):
-        backend = FakeTokyo()
-        gate = self._find_gate_with_length(backend)
-        durations = InstructionDurations.from_backend(backend)
-        self.assertIsNone(durations.dt)
-        self.assertGreater(durations.get(gate, 0, "s"), 0)
-        with self.assertRaises(TranspilerError):
-            durations.get(gate, 0)
-
     def test_update_with_parameters(self):
         durations = InstructionDurations(
             [("rzx", (0, 1), 150, (0.5,)), ("rzx", (0, 1), 300, (1.0,))]
         )
-
         self.assertEqual(durations.get("rzx", [0, 1], parameters=[0.5]), 150)
         self.assertEqual(durations.get("rzx", [0, 1], parameters=[1.0]), 300)
 
-    def _find_gate_with_length(self, backend):
-        """Find a gate that has gate length."""
-        props = backend.properties()
-        for gate in props.gates:
-            try:
-                if props.gate_length(gate.gate, 0):
-                    return gate.gate
-            except Exception:  # pylint: disable=broad-except
-                pass
-        raise ValueError("Unable to find a gate with gate length.")
-
     def test_can_get_unbounded_duration_without_unit_conversion(self):
         param = Parameter("t")
         parameterized_delay = Delay(param, "dt")
@@ -88,3 +60,113 @@ def test_fail_if_get_unbounded_duration_with_unit_conversion_when_dt_is_not_prov
         parameterized_delay = Delay(param, "s")
         with self.assertRaises(TranspilerError):
             InstructionDurations().get(parameterized_delay, 0)
+
+
+class TestInstrctionDurationsFromBackendV1(QiskitTestCase):
+    """Test :meth:`~.from_backend` of :class:`.InstructionDurations` with
+    :class:`.BackendV1`"""
+
+    def setUp(self):
+        super().setUp()
+
+        self.backend = FakeParis()
+        self.backend_config = self.backend.configuration()
+        self.backend_props = self.backend.properties()
+        self.example_qubit = (0,)
+        self.example_gate = "x"
+
+        # Setting dt for the copy of backend to be None
+        self.backend_cpy = deepcopy(self.backend)
+        self.backend_cpy.configuration().dt = None
+
+    def test_backend_dt_equals_inst_dur_dt(self):
+        durations = InstructionDurations.from_backend(self.backend)
+        self.assertEqual(durations.dt, self.backend_config.dt)
+
+    def test_backend_gate_length_equals_inst_dur(self):
+        durations = InstructionDurations.from_backend(self.backend)
+        inst_dur_duration = durations.get(self.example_gate, self.example_qubit[0], "s")
+        backend_inst_dur = self.backend_props.gate_length(
+            gate=self.example_gate, qubits=self.example_qubit
+        )
+        self.assertEqual(inst_dur_duration, backend_inst_dur)
+
+    def test_backend_without_dt_sets_inst_dur_None(self):
+        durations = InstructionDurations.from_backend(self.backend_cpy)
+        self.assertIsNone(durations.dt)
+
+    def test_get_dur_s_with_dt_None(self):
+        durations = InstructionDurations.from_backend(self.backend_cpy)
+        self.assertEqual(
+            durations.get(self.example_gate, self.example_qubit[0], "s"), 3.5555555555555554e-08
+        )
+
+    def test_raise_dur_get_dt_with_backend_dt_None(self):
+        durations = InstructionDurations.from_backend(self.backend_cpy)
+        with self.assertRaises(TranspilerError):
+            durations.get(self.example_gate, self.example_qubit[0])
+
+    def test_works_unequal_dt_dtm(self):
+        self.backend_cpy.configuration().dt = 1.0
+
+        # This is expcted to fail
+        InstructionDurations.from_backend(self.backend_cpy)
+
+        self.backend_cpy.configuration().dt = None  # Resetting to None
+        # Check if dt and dtm were indeed unequal
+        self.assertNotEqual(self.backend_cpy.configuration().dtm, 1.0)
+
+
+class TestInstrctionDurationsFromBackendV2(QiskitTestCase):
+    """Test :meth:`~.from_backend` of :class:`.InstructionDurations` with
+    :class:`.BackendV2`"""
+
+    def setUp(self):
+        super().setUp()
+
+        self.backend = FakePerth()
+        self.example_gate = "x"
+        self.example_qubit = (0,)
+
+        # Setting dt for the copy  for BackendV2 to None
+        self.backend_cpy = deepcopy(self.backend)
+        self.backend_cpy.target.dt = None
+
+    def test_backend_dt_equals_inst_dur_dt(self):
+        durations = InstructionDurations.from_backend(self.backend)
+        self.assertEqual(durations.dt, self.backend.dt)
+
+    def test_backend_gate_length_equals_inst_dur(self):
+        durations = InstructionDurations.from_backend(self.backend)
+        inst_dur_duration = durations.get(
+            inst=self.example_gate, qubits=self.example_qubit[0], unit="s"
+        )
+        backend_inst_dur = self.backend.target._gate_map[self.example_gate][
+            self.example_qubit
+        ].duration
+        self.assertEqual(inst_dur_duration, backend_inst_dur)
+
+    def test_backend_without_dt_sets_inst_dur_None(self):
+        durations = InstructionDurations.from_backend(self.backend_cpy)
+        self.assertIsNone(durations.dt)
+
+    def test_get_dur_s_with_dt_None(self):
+        durations = InstructionDurations.from_backend(self.backend_cpy)
+        self.assertEqual(
+            durations.get(self.example_gate, self.example_qubit[0], "s"), 3.5555555555555554e-08
+        )
+
+    def test_raise_dur_get_dt_with_backend_dt_None(self):
+        durations = InstructionDurations.from_backend(self.backend_cpy)
+        with self.assertRaises(TranspilerError):
+            durations.get(self.example_gate, self.example_qubit[0])
+
+    def test_works_unequal_dt_dtm(self):
+        self.backend_cpy.target.dt = 1.0
+
+        # This is expcted to fail
+        InstructionDurations.from_backend(self.backend_cpy)
+
+        self.backend_cpy.target.dt = None  # Resetting to None
+        # Check if dt and dtm were indeed unequal
+        self.assertNotEqual(self.backend_cpy.dtm, 1.0)