def test_seed(self): """Different seeds yield different results""" seed_1 = 42 seed_2 = 45 cmap5 = FakeTenerife().configuration().coupling_map qr = QuantumRegister(3, "qr") circuit = QuantumCircuit(qr) circuit.cx(qr[1], qr[0]) # qr1 -> qr0 circuit.cx(qr[0], qr[2]) # qr0 -> qr2 circuit.cx(qr[1], qr[2]) # qr1 -> qr2 dag = circuit_to_dag(circuit) pass_1 = VF2Layout(CouplingMap(cmap5), seed=seed_1) pass_1.run(dag) layout_1 = pass_1.property_set["layout"] self.assertEqual(pass_1.property_set["VF2Layout_stop_reason"], "solution found") pass_2 = VF2Layout(CouplingMap(cmap5), seed=seed_2) pass_2.run(dag) layout_2 = pass_2.property_set["layout"] self.assertEqual(pass_2.property_set["VF2Layout_stop_reason"], "solution found") self.assertNotEqual(layout_1, layout_2)
def test_hexagonal_lattice_graph_9_in_25(self): """A 9x9 interaction map in 25x25 coupling map""" graph_9_9 = retworkx.generators.hexagonal_lattice_graph(9, 9) circuit = self.graph_state_from_pygraph(graph_9_9) dag = circuit_to_dag(circuit) pass_ = VF2Layout(self.cmap25, seed=self.seed) pass_.run(dag) self.assertLayout(dag, self.cmap25, pass_.property_set)
def test_3_q_gate(self): """The pass does not handle gates with more than 2 qubits""" seed_1 = 42 cmap5 = FakeTenerife().configuration().coupling_map qr = QuantumRegister(3, "qr") circuit = QuantumCircuit(qr) circuit.ccx(qr[1], qr[0], qr[2]) dag = circuit_to_dag(circuit) pass_1 = VF2Layout(CouplingMap(cmap5), seed=seed_1) with self.assertRaises(TranspilerError): pass_1.run(dag)
def test_2q_circuit_2q_coupling_sd(self): """A simple example, considering the direction 0 -> 1 qr1 -> qr0 """ cmap = CouplingMap([[0, 1]]) qr = QuantumRegister(2, "qr") circuit = QuantumCircuit(qr) circuit.cx(qr[1], qr[0]) # qr1 -> qr0 dag = circuit_to_dag(circuit) pass_ = VF2Layout(cmap, strict_direction=True, seed=self.seed) pass_.run(dag) self.assertLayout(dag, cmap, pass_.property_set, strict_direction=True)
def test_3q_circuit_3q_coupling_non_induced(self): """A simple example, check for non-induced subgraph 1 qr0 -> qr1 -> qr2 / \ 0 - 2 """ cmap = CouplingMap([[0, 1], [1, 2], [2, 0]]) qr = QuantumRegister(3, "qr") circuit = QuantumCircuit(qr) circuit.cx(qr[0], qr[1]) # qr0-> qr1 circuit.cx(qr[1], qr[2]) # qr1-> qr2 dag = circuit_to_dag(circuit) pass_ = VF2Layout(cmap, seed=-1) pass_.run(dag) self.assertLayout(dag, cmap, pass_.property_set)
def test_perfect_fit_Manhattan(self): """A circuit that fits perfectly in Manhattan (65 qubits) See https://github.com/Qiskit/qiskit-terra/issues/5694""" manhattan_cm = FakeManhattan().configuration().coupling_map cmap65 = CouplingMap(manhattan_cm) rows = [x[0] for x in manhattan_cm] cols = [x[1] for x in manhattan_cm] adj_matrix = numpy.zeros((65, 65)) adj_matrix[rows, cols] = 1 circuit = GraphState(adj_matrix).decompose() circuit.measure_all() dag = circuit_to_dag(circuit) pass_ = VF2Layout(cmap65, seed=self.seed) pass_.run(dag) self.assertLayout(dag, cmap65, pass_.property_set)
def test_3q_circuit_Tenerife_sd(self): """3 qubits in Tenerife, considering the direction 1 1 ↙ ↑ ↙ ↑ 0 ← 2 ← 3 0 ← qr2 ← qr1 ↑ ↙ ↑ ↙ 4 qr0 """ cmap5 = CouplingMap(FakeTenerife().configuration().coupling_map) qr = QuantumRegister(3, "qr") circuit = QuantumCircuit(qr) circuit.cx(qr[1], qr[0]) # qr1 -> qr0 circuit.cx(qr[0], qr[2]) # qr0 -> qr2 circuit.cx(qr[1], qr[2]) # qr1 -> qr2 dag = circuit_to_dag(circuit) pass_ = VF2Layout(cmap5, strict_direction=True, seed=self.seed) pass_.run(dag) self.assertLayout(dag, cmap5, pass_.property_set, strict_direction=True)
def test_4q_circuit_Tenerife_loose_nodes(self): """4 qubits in Tenerife, with loose nodes 1 ↙ ↑ 0 ← 2 ← 3 ↑ ↙ 4 """ cmap5 = CouplingMap(FakeTenerife().configuration().coupling_map) qr = QuantumRegister(4, "q") circuit = QuantumCircuit(qr) circuit.cx(qr[1], qr[0]) # qr1 -> qr0 circuit.cx(qr[0], qr[2]) # qr0 -> qr2 dag = circuit_to_dag(circuit) pass_ = VF2Layout(cmap5, seed=self.seed) pass_.run(dag) self.assertLayout(dag, cmap5, pass_.property_set)
def test_9q_circuit_Rueschlikon_sd(self): """9 qubits in Rueschlikon, considering the direction 1 → 2 → 3 → 4 ← 5 ← 6 → 7 ← 8 ↓ ↑ ↓ ↓ ↑ ↓ ↓ ↑ 0 ← 15 → 14 ← 13 ← 12 → 11 → 10 ← 9 """ cmap16 = CouplingMap(FakeRueschlikon().configuration().coupling_map) qr0 = QuantumRegister(4, "q0") qr1 = QuantumRegister(5, "q1") circuit = QuantumCircuit(qr0, qr1) circuit.cx(qr0[1], qr0[2]) # q0[1] -> q0[2] circuit.cx(qr0[0], qr1[3]) # q0[0] -> q1[3] circuit.cx(qr1[4], qr0[2]) # q1[4] -> q0[2] dag = circuit_to_dag(circuit) pass_ = VF2Layout(cmap16, strict_direction=True, seed=self.seed) pass_.run(dag) self.assertLayout(dag, cmap16, pass_.property_set)
def test_5q_circuit_Rueschlikon_no_solution(self): """5 qubits in Rueschlikon, no solution q0[1] ↖ ↗ q0[2] q0[0] q0[3] ↙ ↘ q0[4] """ cmap16 = FakeRueschlikon().configuration().coupling_map qr = QuantumRegister(5, "q") circuit = QuantumCircuit(qr) circuit.cx(qr[0], qr[1]) circuit.cx(qr[0], qr[2]) circuit.cx(qr[0], qr[3]) circuit.cx(qr[0], qr[4]) dag = circuit_to_dag(circuit) pass_ = VF2Layout(CouplingMap(cmap16), seed=self.seed) pass_.run(dag) layout = pass_.property_set["layout"] self.assertIsNone(layout) self.assertEqual(pass_.property_set["VF2Layout_stop_reason"], "nonexistent solution")
def level_3_pass_manager( pass_manager_config: PassManagerConfig) -> StagedPassManager: """Level 3 pass manager: heavy optimization by noise adaptive qubit mapping and gate cancellation using commutativity rules and unitary synthesis. This pass manager applies the user-given initial layout. If none is given, a search for a perfect layout (i.e. one that satisfies all 2-qubit interactions) is conducted. If no such layout is found, and device calibration information is available, the circuit is mapped to the qubits with best readouts and to CX gates with highest fidelity. The pass manager then transforms the circuit to match the coupling constraints. It is then unrolled to the basis, and any flipped cx directions are fixed. Finally, optimizations in the form of commutative gate cancellation, resynthesis of two-qubit unitary blocks, and redundant reset removal are performed. Args: pass_manager_config: configuration of the pass manager. Returns: a level 3 pass manager. Raises: TranspilerError: if the passmanager config is invalid. """ basis_gates = pass_manager_config.basis_gates inst_map = pass_manager_config.inst_map coupling_map = pass_manager_config.coupling_map initial_layout = pass_manager_config.initial_layout layout_method = pass_manager_config.layout_method or "sabre" routing_method = pass_manager_config.routing_method or "sabre" translation_method = pass_manager_config.translation_method or "translator" scheduling_method = pass_manager_config.scheduling_method instruction_durations = pass_manager_config.instruction_durations seed_transpiler = pass_manager_config.seed_transpiler backend_properties = pass_manager_config.backend_properties approximation_degree = pass_manager_config.approximation_degree unitary_synthesis_method = pass_manager_config.unitary_synthesis_method timing_constraints = pass_manager_config.timing_constraints or TimingConstraints( ) unitary_synthesis_plugin_config = pass_manager_config.unitary_synthesis_plugin_config target = pass_manager_config.target # Layout on good qubits if calibration info available, otherwise on dense links _given_layout = SetLayout(initial_layout) def _choose_layout_condition(property_set): # layout hasn't been set yet return not property_set["layout"] def _vf2_match_not_found(property_set): # If a layout hasn't been set by the time we run vf2 layout we need to # run layout if property_set["layout"] is None: return True # if VF2 layout stopped for any reason other than solution found we need # to run layout since VF2 didn't converge. if (property_set["VF2Layout_stop_reason"] is not None and property_set["VF2Layout_stop_reason"] is not VF2LayoutStopReason.SOLUTION_FOUND): return True return False # 2a. If layout method is not set, first try VF2Layout _choose_layout_0 = ([] if pass_manager_config.layout_method else VF2Layout( coupling_map, seed=seed_transpiler, call_limit=int(3e7), # Set call limit to ~60 sec with retworkx 0.10.2 properties=backend_properties, target=target, )) # 2b. if VF2 didn't converge on a solution use layout_method (dense). if layout_method == "trivial": _choose_layout_1 = TrivialLayout(coupling_map) elif layout_method == "dense": _choose_layout_1 = DenseLayout(coupling_map, backend_properties, target=target) elif layout_method == "noise_adaptive": _choose_layout_1 = NoiseAdaptiveLayout(backend_properties) elif layout_method == "sabre": _choose_layout_1 = SabreLayout(coupling_map, max_iterations=4, seed=seed_transpiler) else: raise TranspilerError("Invalid layout method %s." % layout_method) toqm_pass = False if routing_method == "basic": routing_pass = BasicSwap(coupling_map) elif routing_method == "stochastic": routing_pass = StochasticSwap(coupling_map, trials=200, seed=seed_transpiler) elif routing_method == "lookahead": routing_pass = LookaheadSwap(coupling_map, search_depth=5, search_width=6) elif routing_method == "sabre": routing_pass = SabreSwap(coupling_map, heuristic="decay", seed=seed_transpiler) elif routing_method == "toqm": HAS_TOQM.require_now("TOQM-based routing") from qiskit_toqm import ToqmSwap, ToqmStrategyO3, latencies_from_target if initial_layout: raise TranspilerError( "Initial layouts are not supported with TOQM-based routing.") toqm_pass = True # Note: BarrierBeforeFinalMeasurements is skipped intentionally since ToqmSwap # does not yet support barriers. routing_pass = ToqmSwap( coupling_map, strategy=ToqmStrategyO3( latencies_from_target(coupling_map, instruction_durations, basis_gates, backend_properties, target)), ) elif routing_method == "none": routing_pass = Error( msg= "No routing method selected, but circuit is not routed to device. " "CheckMap Error: {check_map_msg}", action="raise", ) else: raise TranspilerError("Invalid routing method %s." % routing_method) # 8. Optimize iteratively until no more change in depth. Removes useless gates # after reset and before measure, commutes gates and optimizes contiguous blocks. _depth_check = [Depth(), FixedPoint("depth")] _size_check = [Size(), FixedPoint("size")] def _opt_control(property_set): return (not property_set["depth_fixed_point"]) or ( not property_set["size_fixed_point"]) _opt = [ Collect2qBlocks(), ConsolidateBlocks(basis_gates=basis_gates, target=target), UnitarySynthesis( basis_gates, approximation_degree=approximation_degree, coupling_map=coupling_map, backend_props=backend_properties, method=unitary_synthesis_method, plugin_config=unitary_synthesis_plugin_config, target=target, ), Optimize1qGatesDecomposition(basis_gates), CommutativeCancellation(), ] # Build pass manager init = common.generate_unroll_3q( target, basis_gates, approximation_degree, unitary_synthesis_method, unitary_synthesis_plugin_config, ) init.append(RemoveResetInZeroState()) init.append(OptimizeSwapBeforeMeasure()) init.append(RemoveDiagonalGatesBeforeMeasure()) if coupling_map or initial_layout: layout = PassManager() layout.append(_given_layout) layout.append(_choose_layout_0, condition=_choose_layout_condition) layout.append(_choose_layout_1, condition=_vf2_match_not_found) layout += common.generate_embed_passmanager(coupling_map) vf2_call_limit = None if pass_manager_config.layout_method is None and pass_manager_config.initial_layout is None: vf2_call_limit = int( 3e7) # Set call limit to ~60 sec with retworkx 0.10.2 routing = common.generate_routing_passmanager( routing_pass, target, coupling_map=coupling_map, vf2_call_limit=vf2_call_limit, backend_properties=backend_properties, seed_transpiler=seed_transpiler, use_barrier_before_measurement=not toqm_pass, ) else: layout = None routing = None translation = common.generate_translation_passmanager( target, basis_gates, translation_method, approximation_degree, coupling_map, backend_properties, unitary_synthesis_method, unitary_synthesis_plugin_config, ) pre_routing = None if toqm_pass: pre_routing = translation optimization = PassManager() unroll = [pass_ for x in translation.passes() for pass_ in x["passes"]] optimization.append(_depth_check + _size_check) if (coupling_map and not coupling_map.is_symmetric) or ( target is not None and target.get_non_global_operation_names(strict_direction=True)): pre_optimization = common.generate_pre_op_passmanager( target, coupling_map, True) _direction = [ pass_ for x in common.generate_pre_op_passmanager( target, coupling_map).passes() for pass_ in x["passes"] ] # For transpiling to a target we need to run GateDirection in the # optimization loop to correct for incorrect directions that might be # inserted by UnitarySynthesis which is direction aware but only via # the coupling map which with a target doesn't give a full picture if target is not None: optimization.append(_opt + unroll + _depth_check + _size_check + _direction, do_while=_opt_control) else: optimization.append(_opt + unroll + _depth_check + _size_check, do_while=_opt_control) else: pre_optimization = common.generate_pre_op_passmanager( remove_reset_in_zero=True) optimization.append(_opt + unroll + _depth_check + _size_check, do_while=_opt_control) opt_loop = _depth_check + _opt + unroll optimization.append(opt_loop, do_while=_opt_control) sched = common.generate_scheduling(instruction_durations, scheduling_method, timing_constraints, inst_map) return StagedPassManager( init=init, layout=layout, pre_routing=pre_routing, routing=routing, translation=translation, pre_optimization=pre_optimization, optimization=optimization, scheduling=sched, )
def level_1_pass_manager(pass_manager_config: PassManagerConfig) -> StagedPassManager: """Level 1 pass manager: light optimization by simple adjacent gate collapsing. This pass manager applies the user-given initial layout. If none is given, and a trivial layout (i-th virtual -> i-th physical) makes the circuit fit the coupling map, that is used. Otherwise, the circuit is mapped to the most densely connected coupling subgraph, and swaps are inserted to map. Any unused physical qubit is allocated as ancilla space. The pass manager then unrolls the circuit to the desired basis, and transforms the circuit to match the coupling map. Finally, optimizations in the form of adjacent gate collapse and redundant reset removal are performed. Args: pass_manager_config: configuration of the pass manager. Returns: a level 1 pass manager. Raises: TranspilerError: if the passmanager config is invalid. """ basis_gates = pass_manager_config.basis_gates inst_map = pass_manager_config.inst_map coupling_map = pass_manager_config.coupling_map initial_layout = pass_manager_config.initial_layout layout_method = pass_manager_config.layout_method or "dense" routing_method = pass_manager_config.routing_method or "stochastic" translation_method = pass_manager_config.translation_method or "translator" scheduling_method = pass_manager_config.scheduling_method instruction_durations = pass_manager_config.instruction_durations seed_transpiler = pass_manager_config.seed_transpiler backend_properties = pass_manager_config.backend_properties approximation_degree = pass_manager_config.approximation_degree unitary_synthesis_method = pass_manager_config.unitary_synthesis_method unitary_synthesis_plugin_config = pass_manager_config.unitary_synthesis_plugin_config timing_constraints = pass_manager_config.timing_constraints or TimingConstraints() target = pass_manager_config.target # Use trivial layout if no layout given _given_layout = SetLayout(initial_layout) def _choose_layout_condition(property_set): return not property_set["layout"] def _trivial_not_perfect(property_set): # Verify that a trivial layout is perfect. If trivial_layout_score > 0 # the layout is not perfect. The layout is unconditionally set by trivial # layout so we need to clear it before contuing. if ( property_set["trivial_layout_score"] is not None and property_set["trivial_layout_score"] != 0 ): return True return False # Use a better layout on densely connected qubits, if circuit needs swaps def _vf2_match_not_found(property_set): # If a layout hasn't been set by the time we run vf2 layout we need to # run layout if property_set["layout"] is None: return True # if VF2 layout stopped for any reason other than solution found we need # to run layout since VF2 didn't converge. if ( property_set["VF2Layout_stop_reason"] is not None and property_set["VF2Layout_stop_reason"] is not VF2LayoutStopReason.SOLUTION_FOUND ): return True return False _choose_layout_0 = ( [] if pass_manager_config.layout_method else [ TrivialLayout(coupling_map), Layout2qDistance(coupling_map, property_name="trivial_layout_score"), ] ) _choose_layout_1 = ( [] if pass_manager_config.layout_method else VF2Layout( coupling_map, seed=seed_transpiler, call_limit=int(5e4), # Set call limit to ~100ms with retworkx 0.10.2 properties=backend_properties, target=target, ) ) if layout_method == "trivial": _improve_layout = TrivialLayout(coupling_map) elif layout_method == "dense": _improve_layout = DenseLayout(coupling_map, backend_properties, target=target) elif layout_method == "noise_adaptive": _improve_layout = NoiseAdaptiveLayout(backend_properties) elif layout_method == "sabre": _improve_layout = SabreLayout(coupling_map, max_iterations=2, seed=seed_transpiler) else: raise TranspilerError("Invalid layout method %s." % layout_method) toqm_pass = False if routing_method == "basic": routing_pass = BasicSwap(coupling_map) elif routing_method == "stochastic": routing_pass = StochasticSwap(coupling_map, trials=20, seed=seed_transpiler) elif routing_method == "lookahead": routing_pass = LookaheadSwap(coupling_map, search_depth=4, search_width=4) elif routing_method == "sabre": routing_pass = SabreSwap(coupling_map, heuristic="lookahead", seed=seed_transpiler) elif routing_method == "toqm": HAS_TOQM.require_now("TOQM-based routing") from qiskit_toqm import ToqmSwap, ToqmStrategyO1, latencies_from_target if initial_layout: raise TranspilerError("Initial layouts are not supported with TOQM-based routing.") toqm_pass = True # Note: BarrierBeforeFinalMeasurements is skipped intentionally since ToqmSwap # does not yet support barriers. routing_pass = ToqmSwap( coupling_map, strategy=ToqmStrategyO1( latencies_from_target( coupling_map, instruction_durations, basis_gates, backend_properties, target ) ), ) elif routing_method == "none": routing_pass = Error( msg="No routing method selected, but circuit is not routed to device. " "CheckMap Error: {check_map_msg}", action="raise", ) else: raise TranspilerError("Invalid routing method %s." % routing_method) # Build optimization loop: merge 1q rotations and cancel CNOT gates iteratively # until no more change in depth _depth_check = [Depth(), FixedPoint("depth")] _size_check = [Size(), FixedPoint("size")] def _opt_control(property_set): return (not property_set["depth_fixed_point"]) or (not property_set["size_fixed_point"]) _opt = [Optimize1qGatesDecomposition(basis_gates), CXCancellation()] unroll_3q = None # Build full pass manager if coupling_map or initial_layout: unroll_3q = common.generate_unroll_3q( target, basis_gates, approximation_degree, unitary_synthesis_method, unitary_synthesis_plugin_config, ) layout = PassManager() layout.append(_given_layout) layout.append(_choose_layout_0, condition=_choose_layout_condition) layout.append(_choose_layout_1, condition=_trivial_not_perfect) layout.append(_improve_layout, condition=_vf2_match_not_found) layout += common.generate_embed_passmanager(coupling_map) vf2_call_limit = None if pass_manager_config.layout_method is None and pass_manager_config.initial_layout is None: vf2_call_limit = int(5e4) # Set call limit to ~100ms with retworkx 0.10.2 routing = common.generate_routing_passmanager( routing_pass, target, coupling_map, vf2_call_limit=vf2_call_limit, backend_properties=backend_properties, seed_transpiler=seed_transpiler, check_trivial=True, use_barrier_before_measurement=not toqm_pass, ) else: layout = None routing = None translation = common.generate_translation_passmanager( target, basis_gates, translation_method, approximation_degree, coupling_map, backend_properties, unitary_synthesis_method, unitary_synthesis_plugin_config, ) pre_routing = None if toqm_pass: pre_routing = translation if (coupling_map and not coupling_map.is_symmetric) or ( target is not None and target.get_non_global_operation_names(strict_direction=True) ): pre_optimization = common.generate_pre_op_passmanager(target, coupling_map, True) else: pre_optimization = common.generate_pre_op_passmanager(remove_reset_in_zero=True) optimization = PassManager() unroll = [pass_ for x in translation.passes() for pass_ in x["passes"]] optimization.append(_depth_check + _size_check) opt_loop = _opt + unroll + _depth_check + _size_check optimization.append(opt_loop, do_while=_opt_control) sched = common.generate_scheduling( instruction_durations, scheduling_method, timing_constraints, inst_map ) return StagedPassManager( init=unroll_3q, layout=layout, pre_routing=pre_routing, routing=routing, translation=translation, pre_optimization=pre_optimization, optimization=optimization, scheduling=sched, )
def level_2_pass_manager( pass_manager_config: PassManagerConfig) -> PassManager: """Level 2 pass manager: medium optimization by initial layout selection and gate cancellation using commutativity rules. This pass manager applies the user-given initial layout. If none is given, a search for a perfect layout (i.e. one that satisfies all 2-qubit interactions) is conducted. If no such layout is found, qubits are laid out on the most densely connected subset which also exhibits the best gate fidelities. The pass manager then transforms the circuit to match the coupling constraints. It is then unrolled to the basis, and any flipped cx directions are fixed. Finally, optimizations in the form of commutative gate cancellation and redundant reset removal are performed. Note: In simulators where ``coupling_map=None``, only the unrolling and optimization stages are done. Args: pass_manager_config: configuration of the pass manager. Returns: a level 2 pass manager. Raises: TranspilerError: if the passmanager config is invalid. """ basis_gates = pass_manager_config.basis_gates inst_map = pass_manager_config.inst_map coupling_map = pass_manager_config.coupling_map initial_layout = pass_manager_config.initial_layout layout_method = pass_manager_config.layout_method or "dense" routing_method = pass_manager_config.routing_method or "stochastic" translation_method = pass_manager_config.translation_method or "translator" scheduling_method = pass_manager_config.scheduling_method instruction_durations = pass_manager_config.instruction_durations seed_transpiler = pass_manager_config.seed_transpiler backend_properties = pass_manager_config.backend_properties approximation_degree = pass_manager_config.approximation_degree unitary_synthesis_method = pass_manager_config.unitary_synthesis_method timing_constraints = pass_manager_config.timing_constraints or TimingConstraints( ) unitary_synthesis_plugin_config = pass_manager_config.unitary_synthesis_plugin_config target = pass_manager_config.target # 1. Unroll to 1q or 2q gates _unroll3q = [ # Use unitary synthesis for basis aware decomposition of UnitaryGates UnitarySynthesis( basis_gates, approximation_degree=approximation_degree, method=unitary_synthesis_method, min_qubits=3, plugin_config=unitary_synthesis_plugin_config, ), Unroll3qOrMore(), ] # 2. Search for a perfect layout, or choose a dense layout, if no layout given _given_layout = SetLayout(initial_layout) def _choose_layout_condition(property_set): # layout hasn't been set yet return not property_set["layout"] def _vf2_match_not_found(property_set): # If a layout hasn't been set by the time we run vf2 layout we need to # run layout if property_set["layout"] is None: return True # if VF2 layout stopped for any reason other than solution found we need # to run layout since VF2 didn't converge. if (property_set["VF2Layout_stop_reason"] is not None and property_set["VF2Layout_stop_reason"] is not VF2LayoutStopReason.SOLUTION_FOUND): return True return False # 2a. Try using VF2 layout to find a perfect layout _choose_layout_0 = ([] if pass_manager_config.layout_method else VF2Layout( coupling_map, seed=seed_transpiler, call_limit=int(5e6), # Set call limit to ~10 sec with retworkx 0.10.2 time_limit=10.0, properties=backend_properties, )) # 2b. if VF2 layout doesn't converge on a solution use layout_method (dense) to get a layout if layout_method == "trivial": _choose_layout_1 = TrivialLayout(coupling_map) elif layout_method == "dense": _choose_layout_1 = DenseLayout(coupling_map, backend_properties) elif layout_method == "noise_adaptive": _choose_layout_1 = NoiseAdaptiveLayout(backend_properties) elif layout_method == "sabre": _choose_layout_1 = SabreLayout(coupling_map, max_iterations=2, seed=seed_transpiler) else: raise TranspilerError("Invalid layout method %s." % layout_method) # 3. Extend dag/layout with ancillas using the full coupling map _embed = [ FullAncillaAllocation(coupling_map), EnlargeWithAncilla(), ApplyLayout() ] # 4. Swap to fit the coupling map _swap_check = CheckMap(coupling_map) def _swap_condition(property_set): return not property_set["is_swap_mapped"] _swap = [BarrierBeforeFinalMeasurements()] if routing_method == "basic": _swap += [BasicSwap(coupling_map)] elif routing_method == "stochastic": _swap += [ StochasticSwap(coupling_map, trials=20, seed=seed_transpiler) ] elif routing_method == "lookahead": _swap += [LookaheadSwap(coupling_map, search_depth=5, search_width=5)] elif routing_method == "sabre": _swap += [ SabreSwap(coupling_map, heuristic="decay", seed=seed_transpiler) ] elif routing_method == "none": _swap += [ Error( msg= ("No routing method selected, but circuit is not routed to device. " "CheckMap Error: {check_map_msg}"), action="raise", ) ] else: raise TranspilerError("Invalid routing method %s." % routing_method) # 5. Unroll to the basis if translation_method == "unroller": _unroll = [Unroller(basis_gates)] elif translation_method == "translator": from qiskit.circuit.equivalence_library import SessionEquivalenceLibrary as sel _unroll = [ # Use unitary synthesis for basis aware decomposition of UnitaryGates before # custom unrolling UnitarySynthesis( basis_gates, approximation_degree=approximation_degree, coupling_map=coupling_map, backend_props=backend_properties, method=unitary_synthesis_method, plugin_config=unitary_synthesis_plugin_config, ), UnrollCustomDefinitions(sel, basis_gates), BasisTranslator(sel, basis_gates, target), ] elif translation_method == "synthesis": _unroll = [ # Use unitary synthesis for basis aware decomposition of UnitaryGates before # collection UnitarySynthesis( basis_gates, approximation_degree=approximation_degree, coupling_map=coupling_map, backend_props=backend_properties, method=unitary_synthesis_method, plugin_config=unitary_synthesis_plugin_config, min_qubits=3, ), Unroll3qOrMore(), Collect2qBlocks(), ConsolidateBlocks(basis_gates=basis_gates, target=target), UnitarySynthesis( basis_gates, approximation_degree=approximation_degree, coupling_map=coupling_map, backend_props=backend_properties, method=unitary_synthesis_method, plugin_config=unitary_synthesis_plugin_config, ), ] else: raise TranspilerError("Invalid translation method %s." % translation_method) # 6. Fix any bad CX directions _direction_check = [CheckGateDirection(coupling_map, target)] def _direction_condition(property_set): return not property_set["is_direction_mapped"] _direction = [GateDirection(coupling_map, target)] # 7. Remove zero-state reset _reset = RemoveResetInZeroState() # 8. 1q rotation merge and commutative cancellation iteratively until no more change in depth _depth_check = [Depth(), FixedPoint("depth")] def _opt_control(property_set): return not property_set["depth_fixed_point"] _opt = [ Optimize1qGatesDecomposition(basis_gates), CommutativeCancellation(basis_gates=basis_gates), ] # 9. Unify all durations (either SI, or convert to dt if known) # Schedule the circuit only when scheduling_method is supplied _time_unit_setup = [ContainsInstruction("delay")] _time_unit_conversion = [TimeUnitConversion(instruction_durations)] def _contains_delay(property_set): return property_set["contains_delay"] _scheduling = [] if scheduling_method: _scheduling += _time_unit_conversion if scheduling_method in {"alap", "as_late_as_possible"}: _scheduling += [ALAPSchedule(instruction_durations), PadDelay()] elif scheduling_method in {"asap", "as_soon_as_possible"}: _scheduling += [ASAPSchedule(instruction_durations), PadDelay()] else: raise TranspilerError("Invalid scheduling method %s." % scheduling_method) # 10. Call measure alignment. Should come after scheduling. if (timing_constraints.granularity != 1 or timing_constraints.min_length != 1 or timing_constraints.acquire_alignment != 1): _alignments = [ ValidatePulseGates(granularity=timing_constraints.granularity, min_length=timing_constraints.min_length), AlignMeasures(alignment=timing_constraints.acquire_alignment), ] else: _alignments = [] # Build pass manager pm2 = PassManager() if coupling_map or initial_layout: pm2.append(_given_layout) pm2.append(_unroll3q) pm2.append(_choose_layout_0, condition=_choose_layout_condition) pm2.append(_choose_layout_1, condition=_vf2_match_not_found) pm2.append(_embed) pm2.append(_swap_check) pm2.append(_swap, condition=_swap_condition) pm2.append(_unroll) if (coupling_map and not coupling_map.is_symmetric) or ( target is not None and target.get_non_global_operation_names(strict_direction=True)): pm2.append(_direction_check) pm2.append(_direction, condition=_direction_condition) pm2.append(_reset) pm2.append(_depth_check + _opt + _unroll, do_while=_opt_control) if inst_map and inst_map.has_custom_gate(): pm2.append(PulseGates(inst_map=inst_map)) if scheduling_method: pm2.append(_scheduling) elif instruction_durations: pm2.append(_time_unit_setup) pm2.append(_time_unit_conversion, condition=_contains_delay) pm2.append(_alignments) return pm2
def level_2_pass_manager( pass_manager_config: PassManagerConfig) -> StagedPassManager: """Level 2 pass manager: medium optimization by initial layout selection and gate cancellation using commutativity rules. This pass manager applies the user-given initial layout. If none is given, a search for a perfect layout (i.e. one that satisfies all 2-qubit interactions) is conducted. If no such layout is found, qubits are laid out on the most densely connected subset which also exhibits the best gate fidelities. The pass manager then transforms the circuit to match the coupling constraints. It is then unrolled to the basis, and any flipped cx directions are fixed. Finally, optimizations in the form of commutative gate cancellation and redundant reset removal are performed. Args: pass_manager_config: configuration of the pass manager. Returns: a level 2 pass manager. Raises: TranspilerError: if the passmanager config is invalid. """ basis_gates = pass_manager_config.basis_gates inst_map = pass_manager_config.inst_map coupling_map = pass_manager_config.coupling_map initial_layout = pass_manager_config.initial_layout layout_method = pass_manager_config.layout_method or "dense" routing_method = pass_manager_config.routing_method or "stochastic" translation_method = pass_manager_config.translation_method or "translator" scheduling_method = pass_manager_config.scheduling_method instruction_durations = pass_manager_config.instruction_durations seed_transpiler = pass_manager_config.seed_transpiler backend_properties = pass_manager_config.backend_properties approximation_degree = pass_manager_config.approximation_degree unitary_synthesis_method = pass_manager_config.unitary_synthesis_method timing_constraints = pass_manager_config.timing_constraints or TimingConstraints( ) unitary_synthesis_plugin_config = pass_manager_config.unitary_synthesis_plugin_config target = pass_manager_config.target # Search for a perfect layout, or choose a dense layout, if no layout given _given_layout = SetLayout(initial_layout) def _choose_layout_condition(property_set): # layout hasn't been set yet return not property_set["layout"] def _vf2_match_not_found(property_set): # If a layout hasn't been set by the time we run vf2 layout we need to # run layout if property_set["layout"] is None: return True # if VF2 layout stopped for any reason other than solution found we need # to run layout since VF2 didn't converge. if (property_set["VF2Layout_stop_reason"] is not None and property_set["VF2Layout_stop_reason"] is not VF2LayoutStopReason.SOLUTION_FOUND): return True return False # Try using VF2 layout to find a perfect layout _choose_layout_0 = ([] if pass_manager_config.layout_method else VF2Layout( coupling_map, seed=seed_transpiler, call_limit=int(5e6), # Set call limit to ~10 sec with retworkx 0.10.2 properties=backend_properties, target=target, )) if layout_method == "trivial": _choose_layout_1 = TrivialLayout(coupling_map) elif layout_method == "dense": _choose_layout_1 = DenseLayout(coupling_map, backend_properties, target=target) elif layout_method == "noise_adaptive": _choose_layout_1 = NoiseAdaptiveLayout(backend_properties) elif layout_method == "sabre": _choose_layout_1 = SabreLayout(coupling_map, max_iterations=2, seed=seed_transpiler) else: raise TranspilerError("Invalid layout method %s." % layout_method) toqm_pass = False if routing_method == "basic": routing_pass = BasicSwap(coupling_map) elif routing_method == "stochastic": routing_pass = StochasticSwap(coupling_map, trials=20, seed=seed_transpiler) elif routing_method == "lookahead": routing_pass = LookaheadSwap(coupling_map, search_depth=5, search_width=5) elif routing_method == "sabre": routing_pass = SabreSwap(coupling_map, heuristic="decay", seed=seed_transpiler) elif routing_method == "toqm": HAS_TOQM.require_now("TOQM-based routing") from qiskit_toqm import ToqmSwap, ToqmStrategyO2, latencies_from_target if initial_layout: raise TranspilerError( "Initial layouts are not supported with TOQM-based routing.") toqm_pass = True # Note: BarrierBeforeFinalMeasurements is skipped intentionally since ToqmSwap # does not yet support barriers. routing_pass = ToqmSwap( coupling_map, strategy=ToqmStrategyO2( latencies_from_target(coupling_map, instruction_durations, basis_gates, backend_properties, target)), ) elif routing_method == "none": routing_pass = Error( msg= "No routing method selected, but circuit is not routed to device. " "CheckMap Error: {check_map_msg}", action="raise", ) else: raise TranspilerError("Invalid routing method %s." % routing_method) # Build optimization loop: 1q rotation merge and commutative cancellation iteratively until # no more change in depth _depth_check = [Depth(), FixedPoint("depth")] _size_check = [Size(), FixedPoint("size")] def _opt_control(property_set): return (not property_set["depth_fixed_point"]) or ( not property_set["size_fixed_point"]) _opt = [ Optimize1qGatesDecomposition(basis_gates), CommutativeCancellation(basis_gates=basis_gates), ] unroll_3q = None # Build pass manager if coupling_map or initial_layout: unroll_3q = common.generate_unroll_3q( target, basis_gates, approximation_degree, unitary_synthesis_method, unitary_synthesis_plugin_config, ) layout = PassManager() layout.append(_given_layout) layout.append(_choose_layout_0, condition=_choose_layout_condition) layout.append(_choose_layout_1, condition=_vf2_match_not_found) layout += common.generate_embed_passmanager(coupling_map) vf2_call_limit = None if pass_manager_config.layout_method is None and pass_manager_config.initial_layout is None: vf2_call_limit = int( 5e6) # Set call limit to ~10 sec with retworkx 0.10.2 routing = common.generate_routing_passmanager( routing_pass, target, coupling_map=coupling_map, vf2_call_limit=vf2_call_limit, backend_properties=backend_properties, seed_transpiler=seed_transpiler, use_barrier_before_measurement=not toqm_pass, ) else: layout = None routing = None translation = common.generate_translation_passmanager( target, basis_gates, translation_method, approximation_degree, coupling_map, backend_properties, unitary_synthesis_method, unitary_synthesis_plugin_config, ) pre_routing = None if toqm_pass: pre_routing = translation if (coupling_map and not coupling_map.is_symmetric) or ( target is not None and target.get_non_global_operation_names(strict_direction=True)): pre_optimization = common.generate_pre_op_passmanager( target, coupling_map, True) else: pre_optimization = common.generate_pre_op_passmanager( remove_reset_in_zero=True) optimization = PassManager() unroll = [pass_ for x in translation.passes() for pass_ in x["passes"]] optimization.append(_depth_check + _size_check) opt_loop = _opt + unroll + _depth_check + _size_check optimization.append(opt_loop, do_while=_opt_control) sched = common.generate_scheduling(instruction_durations, scheduling_method, timing_constraints, inst_map) return StagedPassManager( init=unroll_3q, layout=layout, pre_routing=pre_routing, routing=routing, translation=translation, pre_optimization=pre_optimization, optimization=optimization, scheduling=sched, )
def level_1_pass_manager( pass_manager_config: PassManagerConfig) -> PassManager: """Level 1 pass manager: light optimization by simple adjacent gate collapsing. This pass manager applies the user-given initial layout. If none is given, and a trivial layout (i-th virtual -> i-th physical) makes the circuit fit the coupling map, that is used. Otherwise, the circuit is mapped to the most densely connected coupling subgraph, and swaps are inserted to map. Any unused physical qubit is allocated as ancilla space. The pass manager then unrolls the circuit to the desired basis, and transforms the circuit to match the coupling map. Finally, optimizations in the form of adjacent gate collapse and redundant reset removal are performed. Note: In simulators where ``coupling_map=None``, only the unrolling and optimization stages are done. Args: pass_manager_config: configuration of the pass manager. Returns: a level 1 pass manager. Raises: TranspilerError: if the passmanager config is invalid. """ basis_gates = pass_manager_config.basis_gates inst_map = pass_manager_config.inst_map coupling_map = pass_manager_config.coupling_map initial_layout = pass_manager_config.initial_layout layout_method = pass_manager_config.layout_method or "dense" routing_method = pass_manager_config.routing_method or "stochastic" translation_method = pass_manager_config.translation_method or "translator" scheduling_method = pass_manager_config.scheduling_method instruction_durations = pass_manager_config.instruction_durations seed_transpiler = pass_manager_config.seed_transpiler backend_properties = pass_manager_config.backend_properties approximation_degree = pass_manager_config.approximation_degree unitary_synthesis_method = pass_manager_config.unitary_synthesis_method unitary_synthesis_plugin_config = pass_manager_config.unitary_synthesis_plugin_config timing_constraints = pass_manager_config.timing_constraints or TimingConstraints( ) target = pass_manager_config.target # 1. Use trivial layout if no layout given if that isn't perfect use vf2 layout _given_layout = SetLayout(initial_layout) def _choose_layout_condition(property_set): return not property_set["layout"] def _trivial_not_perfect(property_set): # Verify that a trivial layout is perfect. If trivial_layout_score > 0 # the layout is not perfect. The layout is unconditionally set by trivial # layout so we need to clear it before contuing. if (property_set["trivial_layout_score"] is not None and property_set["trivial_layout_score"] != 0): return True return False def _vf2_match_not_found(property_set): # If a layout hasn't been set by the time we run vf2 layout we need to # run layout if property_set["layout"] is None: return True # if VF2 layout stopped for any reason other than solution found we need # to run layout since VF2 didn't converge. if (property_set["VF2Layout_stop_reason"] is not None and property_set["VF2Layout_stop_reason"] is not VF2LayoutStopReason.SOLUTION_FOUND): return True return False _choose_layout_0 = ([] if pass_manager_config.layout_method else [ TrivialLayout(coupling_map), Layout2qDistance(coupling_map, property_name="trivial_layout_score"), ]) _choose_layout_1 = ([] if pass_manager_config.layout_method else VF2Layout( coupling_map, seed=seed_transpiler, call_limit=int(5e4), # Set call limit to ~100ms with retworkx 0.10.2 time_limit=0.1, properties=backend_properties, target=target, )) # 2. Decompose so only 1-qubit and 2-qubit gates remain _unroll3q = [ # Use unitary synthesis for basis aware decomposition of UnitaryGates UnitarySynthesis( basis_gates, approximation_degree=approximation_degree, method=unitary_synthesis_method, min_qubits=3, plugin_config=unitary_synthesis_plugin_config, target=target, ), Unroll3qOrMore(), ] # 3. Use a better layout on densely connected qubits, if circuit needs swaps if layout_method == "trivial": _improve_layout = TrivialLayout(coupling_map) elif layout_method == "dense": _improve_layout = DenseLayout(coupling_map, backend_properties, target=target) elif layout_method == "noise_adaptive": _improve_layout = NoiseAdaptiveLayout(backend_properties) elif layout_method == "sabre": _improve_layout = SabreLayout(coupling_map, max_iterations=2, seed=seed_transpiler) else: raise TranspilerError("Invalid layout method %s." % layout_method) # 4. Extend dag/layout with ancillas using the full coupling map _embed = [ FullAncillaAllocation(coupling_map), EnlargeWithAncilla(), ApplyLayout() ] # 5. Swap to fit the coupling map _swap_check = CheckMap(coupling_map) def _swap_condition(property_set): return not property_set["is_swap_mapped"] _swap = [BarrierBeforeFinalMeasurements()] if routing_method == "basic": _swap += [BasicSwap(coupling_map)] elif routing_method == "stochastic": _swap += [ StochasticSwap(coupling_map, trials=20, seed=seed_transpiler) ] elif routing_method == "lookahead": _swap += [LookaheadSwap(coupling_map, search_depth=4, search_width=4)] elif routing_method == "sabre": _swap += [ SabreSwap(coupling_map, heuristic="lookahead", seed=seed_transpiler) ] elif routing_method == "none": _swap += [ Error( msg= ("No routing method selected, but circuit is not routed to device. " "CheckMap Error: {check_map_msg}"), action="raise", ) ] else: raise TranspilerError("Invalid routing method %s." % routing_method) # 6. Unroll to the basis if translation_method == "unroller": _unroll = [Unroller(basis_gates)] elif translation_method == "translator": from qiskit.circuit.equivalence_library import SessionEquivalenceLibrary as sel _unroll = [ # Use unitary synthesis for basis aware decomposition of UnitaryGates before # custom unrolling UnitarySynthesis( basis_gates, approximation_degree=approximation_degree, coupling_map=coupling_map, method=unitary_synthesis_method, backend_props=backend_properties, plugin_config=unitary_synthesis_plugin_config, target=target, ), UnrollCustomDefinitions(sel, basis_gates), BasisTranslator(sel, basis_gates, target), ] elif translation_method == "synthesis": _unroll = [ # Use unitary synthesis for basis aware decomposition of UnitaryGates before # collection UnitarySynthesis( basis_gates, approximation_degree=approximation_degree, coupling_map=coupling_map, method=unitary_synthesis_method, backend_props=backend_properties, min_qubits=3, target=target, ), Unroll3qOrMore(), Collect2qBlocks(), ConsolidateBlocks(basis_gates=basis_gates, target=target), UnitarySynthesis( basis_gates, approximation_degree=approximation_degree, coupling_map=coupling_map, method=unitary_synthesis_method, backend_props=backend_properties, plugin_config=unitary_synthesis_plugin_config, target=target, ), ] else: raise TranspilerError("Invalid translation method %s." % translation_method) # 7. Fix any bad CX directions _direction_check = [CheckGateDirection(coupling_map, target)] def _direction_condition(property_set): return not property_set["is_direction_mapped"] _direction = [GateDirection(coupling_map, target)] # 8. Remove zero-state reset _reset = RemoveResetInZeroState() # 9. Merge 1q rotations and cancel CNOT gates iteratively until no more change in depth # or size of circuit _depth_check = [Depth(), FixedPoint("depth")] _size_check = [Size(), FixedPoint("size")] def _opt_control(property_set): return (not property_set["depth_fixed_point"]) or ( not property_set["size_fixed_point"]) _opt = [Optimize1qGatesDecomposition(basis_gates), CXCancellation()] # Build pass manager pm1 = PassManager() if coupling_map or initial_layout: pm1.append(_given_layout) pm1.append(_unroll3q) pm1.append(_choose_layout_0, condition=_choose_layout_condition) pm1.append(_choose_layout_1, condition=_trivial_not_perfect) pm1.append(_improve_layout, condition=_vf2_match_not_found) pm1.append(_embed) pm1.append(_swap_check) pm1.append(_swap, condition=_swap_condition) pm1.append(_unroll) if (coupling_map and not coupling_map.is_symmetric) or ( target is not None and target.get_non_global_operation_names(strict_direction=True)): pm1.append(_direction_check) pm1.append(_direction, condition=_direction_condition) pm1.append(_reset) pm1.append(_depth_check + _size_check) pm1.append(_opt + _unroll + _depth_check + _size_check, do_while=_opt_control) if inst_map and inst_map.has_custom_gate(): pm1.append(PulseGates(inst_map=inst_map)) # 10. Unify all durations (either SI, or convert to dt if known) # Schedule the circuit only when scheduling_method is supplied # Apply alignment analysis regardless of scheduling for delay validation. if scheduling_method: # Do scheduling after unit conversion. scheduler = { "alap": ALAPScheduleAnalysis, "as_late_as_possible": ALAPScheduleAnalysis, "asap": ASAPScheduleAnalysis, "as_soon_as_possible": ASAPScheduleAnalysis, } pm1.append(TimeUnitConversion(instruction_durations)) try: pm1.append(scheduler[scheduling_method](instruction_durations)) except KeyError as ex: raise TranspilerError("Invalid scheduling method %s." % scheduling_method) from ex elif instruction_durations: # No scheduling. But do unit conversion for delays. def _contains_delay(property_set): return property_set["contains_delay"] pm1.append(ContainsInstruction("delay")) pm1.append(TimeUnitConversion(instruction_durations), condition=_contains_delay) if (timing_constraints.granularity != 1 or timing_constraints.min_length != 1 or timing_constraints.acquire_alignment != 1 or timing_constraints.pulse_alignment != 1): # Run alignment analysis regardless of scheduling. def _require_alignment(property_set): return property_set["reschedule_required"] pm1.append( InstructionDurationCheck( acquire_alignment=timing_constraints.acquire_alignment, pulse_alignment=timing_constraints.pulse_alignment, )) pm1.append( ConstrainedReschedule( acquire_alignment=timing_constraints.acquire_alignment, pulse_alignment=timing_constraints.pulse_alignment, ), condition=_require_alignment, ) pm1.append( ValidatePulseGates( granularity=timing_constraints.granularity, min_length=timing_constraints.min_length, )) if scheduling_method: # Call padding pass if circuit is scheduled pm1.append(PadDelay()) return pm1