def test_permute_wires_5(self):
"""This is the same case as permute_wires_4
except the single qubit gate is after the two-qubit
gate, so the layout is adjusted.
qr0:--(+)------
|
qr1:---|-------
|
qr2:---|-------
|
qr3:---.--[H]--
Coupling map: [0]--[1]--[2]--[3]
qr0:-x-----------
|
qr1:-x--(+)------
|
qr2:-x---.--[H]--
|
qr3:-x-----------
"""
coupling = CouplingMap([[0, 1], [1, 2], [2, 3]])
qr = QuantumRegister(4, 'q')
circuit = QuantumCircuit(qr)
circuit.cx(qr[3], qr[0])
circuit.h(qr[3])
dag = circuit_to_dag(circuit)
pass_ = StochasticSwap(coupling, 20, 13)
after = pass_.run(dag)
expected = QuantumCircuit(qr)
expected.swap(qr[0], qr[1])
expected.swap(qr[2], qr[3])
expected.cx(qr[2], qr[1])
expected.h(qr[2])
self.assertEqual(circuit_to_dag(expected), after)
def test_permute_wires_4(self):
"""No qubit label permutation occurs if the first
layer has only single-qubit gates. This is suboptimal
but seems to be the current behavior.
qr0:------(+)--
|
qr1:-------|---
|
qr2:-------|---
|
qr3:--[H]--.---
Coupling map: [0]--[1]--[2]--[3]
qr0:------X---------
|
qr1:------X-(+)-----
|
qr2:------X--.------
|
qr3:-[H]--X---------
"""
coupling = CouplingMap([[0, 1], [1, 2], [2, 3]])
qr = QuantumRegister(4, 'q')
circuit = QuantumCircuit(qr)
circuit.h(qr[3])
circuit.cx(qr[3], qr[0])
dag = circuit_to_dag(circuit)
pass_ = StochasticSwap(coupling, 20, 13)
after = pass_.run(dag)
expected = QuantumCircuit(qr)
expected.h(qr[3])
expected.swap(qr[2], qr[3])
expected.swap(qr[0], qr[1])
expected.cx(qr[2], qr[1])
self.assertEqual(circuit_to_dag(expected), after)
def test_map_with_layout(self):
"""Test using an initial layout."""
coupling = CouplingMap([[0, 1], [1, 2]])
qra = QuantumRegister(2, 'qa')
qrb = QuantumRegister(1, 'qb')
cr = ClassicalRegister(3, 'r')
circ = QuantumCircuit(qra, qrb, cr)
circ.cx(qra[0], qrb[0])
circ.measure(qra[0], cr[0])
circ.measure(qra[1], cr[1])
circ.measure(qrb[0], cr[2])
dag = circuit_to_dag(circ)
layout = Layout({
(QuantumRegister(2, 'qa'), 0): 0,
(QuantumRegister(2, 'qa'), 1): 1,
(QuantumRegister(1, 'qb'), 0): 2
})
pass_ = StochasticSwap(coupling, layout, 20, 13)
after = pass_.run(dag)
self.assertEqual(dag, after)
def test_permute_wires_3(self):
"""
qr0:--(+)---.--
| |
qr1:---|----|--
| |
qr2:---|----|--
| |
qr3:---.---(+)-
Coupling map: [0]--[1]--[2]--[3]
"""
coupling = CouplingMap([[0, 1], [1, 2], [2, 3]])
qr = QuantumRegister(4, 'q')
circuit = QuantumCircuit(qr)
circuit.cx(qr[0], qr[3])
circuit.cx(qr[3], qr[0])
dag = circuit_to_dag(circuit)
pass_ = StochasticSwap(coupling, None, 20, 13)
after = pass_.run(dag)
self.assertEqual(dag, after)
def test_trivial_case(self):
"""
q0:--(+)-[H]-(+)-
| |
q1:---.-------|--
|
q2:-----------.--
Coupling map: [1]--[0]--[2]
"""
coupling = CouplingMap(couplinglist=[[0, 1], [0, 2]])
qr = QuantumRegister(3, 'q')
circuit = QuantumCircuit(qr)
circuit.cx(qr[0], qr[1])
circuit.h(qr[0])
circuit.cx(qr[0], qr[2])
dag = circuit_to_dag(circuit)
pass_ = StochasticSwap(coupling, None, 20, 13)
after = pass_.run(dag)
self.assertEqual(dag, after)
def test_only_output_cx_and_swaps_in_coupling_map(self):
"""Test that output DAG contains only 2q gates from the the coupling map."""
coupling = CouplingMap([[0, 1], [1, 2], [2, 3]])
qr = QuantumRegister(4, 'q')
cr = ClassicalRegister(4, 'c')
circuit = QuantumCircuit(qr, cr)
circuit.h(qr[0])
circuit.cx(qr[0], qr[1])
circuit.cx(qr[0], qr[2])
circuit.cx(qr[0], qr[3])
circuit.measure(qr, cr)
dag = circuit_to_dag(circuit)
pass_ = StochasticSwap(coupling, 20, 5)
after = pass_.run(dag)
valid_couplings = [
set([qr[a], qr[b]]) for (a, b) in coupling.get_edges()
]
for _2q_gate in after.twoQ_gates():
self.assertIn(set(_2q_gate.qargs), valid_couplings)
def test_permute_wires_1(self):
"""All of the test_permute_wires tests are derived
from the basic mapper tests. In this case, the
stochastic mapper handles a single
layer by qubit label permutations so as not to
introduce additional swap gates. The new
initial layout is found in pass_.initial_layout.
q0:-------
q1:--(+)--
|
q2:---.---
Coupling map: [1]--[0]--[2]
"""
coupling = CouplingMap([[0, 1], [0, 2]])
qr = QuantumRegister(3, 'q')
circuit = QuantumCircuit(qr)
circuit.cx(qr[1], qr[2])
dag = circuit_to_dag(circuit)
pass_ = StochasticSwap(coupling, None, 20, 13)
after = pass_.run(dag)
self.assertEqual(dag, after)
def test_trivial_in_same_layer(self):
"""
q0:--(+)--
|
q1:---.---
q2:--(+)--
|
q3:---.---
Coupling map: [0]--[1]--[2]--[3]
"""
coupling = CouplingMap(couplinglist=[[0, 1], [1, 2], [2, 3]])
qr = QuantumRegister(4, 'q')
circuit = QuantumCircuit(qr)
circuit.cx(qr[2], qr[3])
circuit.cx(qr[0], qr[1])
dag = circuit_to_dag(circuit)
pass_ = StochasticSwap(coupling, None, 20, 13)
after = pass_.run(dag)
self.assertEqual(dag, after)
def test_multiple_registers_with_good_layout(self):
"""
Test two registers + measurements using a layout.
The layout makes all gates nearest neighbor.
"""
coupling = CouplingMap([[0, 1], [1, 2]])
qr_q = QuantumRegister(2, 'q')
qr_a = QuantumRegister(1, 'a')
cr_c = ClassicalRegister(3, 'c')
circ = QuantumCircuit(qr_q, qr_a, cr_c)
circ.cx(qr_q[0], qr_a[0])
circ.cx(qr_q[1], qr_a[0])
circ.measure(qr_q[0], cr_c[0])
circ.measure(qr_q[1], cr_c[1])
circ.measure(qr_a[0], cr_c[2])
dag = circuit_to_dag(circ)
layout = Layout({qr_q[0]: 0, qr_a[0]: 1, qr_q[1]: 2})
pass_ = StochasticSwap(coupling, layout, 20, 13)
after = pass_.run(dag)
self.assertEqual(dag, after)
def test_single_gates_omitted(self):
"""Test if single qubit gates are omitted."""
coupling_map = [[0, 1], [1, 0], [1, 2], [1, 3], [2, 1], [3, 1], [3, 4],
[4, 3]]
# q_0: ──■──────────────────
# │
# q_1: ──┼─────────■────────
# │ ┌─┴─┐
# q_2: ──┼───────┤ X ├──────
# │ ┌────┴───┴─────┐
# q_3: ──┼──┤ U(1,1.5,0.7) ├
# ┌─┴─┐└──────────────┘
# q_4: ┤ X ├────────────────
# └───┘
qr = QuantumRegister(5, "q")
cr = ClassicalRegister(5, "c")
circuit = QuantumCircuit(qr, cr)
circuit.cx(qr[0], qr[4])
circuit.cx(qr[1], qr[2])
circuit.u(1, 1.5, 0.7, qr[3])
# q_0: ─────────────────X──────
# │
# q_1: ───────■─────────X───■──
# ┌─┴─┐ │
# q_2: ─────┤ X ├───────────┼──
# ┌────┴───┴─────┐ ┌─┴─┐
# q_3: ┤ U(1,1.5,0.7) ├─X─┤ X ├
# └──────────────┘ │ └───┘
# q_4: ─────────────────X──────
expected = QuantumCircuit(qr, cr)
expected.cx(qr[1], qr[2])
expected.u(1, 1.5, 0.7, qr[3])
expected.swap(qr[0], qr[1])
expected.swap(qr[3], qr[4])
expected.cx(qr[1], qr[3])
expected_dag = circuit_to_dag(expected)
stochastic = StochasticSwap(CouplingMap(coupling_map), seed=0)
after = PassManager(stochastic).run(circuit)
after = circuit_to_dag(after)
self.assertEqual(expected_dag, after)
def run(self, quantum_circuit):
dag_circuit = circuit_to_dag(quantum_circuit)
init_time = time.time()
self.parameters["TIME_START"] = init_time
initial_mapping = []
if self.parameters["initial_map"] == K7MInitialMapping.RANDOM:
# Only the first positions which correspond to the circuit qubits
initial_mapping = numpy.random.permutation(
self.parameters["nisq_qubits"])
initial_mapping = initial_mapping[:dag_circuit.num_qubits()]
elif self.parameters["initial_map"] == K7MInitialMapping.LINEAR:
initial_mapping = list(range(dag_circuit.num_qubits()))
elif self.parameters["initial_map"] == K7MInitialMapping.HEURISTIC:
initial_mapping = cuthill_order(dag_circuit, self.coupling_obj,
self.parameters)
init_time = time.time() - init_time
if initial_mapping is None:
return None, init_time, None
# print(initial_mapping)
#
# return quantum_circuit
print(" .......")
original_pm = PassManager()
optimal_layout = Layout()
for c_idx, p_idx in enumerate(initial_mapping):
optimal_layout.add(quantum_circuit.qregs[0][c_idx], p_idx)
original_pm.append([
SetLayout(optimal_layout),
ApplyLayout(),
StochasticSwap(self.coupling_obj.coupling, seed=0),
Decompose(gate=qiskit.extensions.SwapGate)
])
return original_pm.run(quantum_circuit), init_time, initial_mapping
def pick_label(circ, backend, coupling_map, optimization_level, show=False):
'''
Funzione che restituisce il dizionario con il mapping, scegliendo come label layout quello che minimizza la depth
del circuito tra dense layout e noise_adaptive sommata alla depth delle operazioni dopo il routing.
In questa maniera tengo anche conto di qual'è il layout che permette di minimizzare le operazioni di swap
'''
new_circ_lv3 = transpile(circ,
backend=backend,
optimization_level=optimization_level)
new_circ_lv3_na = transpile(circ,
backend=backend,
optimization_level=optimization_level,
layout_method='noise_adaptive')
#plot_circuit_layout(new_circ_lv3_na, backend).show()
#plot_circuit_layout(new_circ_lv3, backend).show()
cp = CouplingMap(couplinglist=coupling_map)
depths = []
for qc in [new_circ_lv3_na, new_circ_lv3]:
depth = qc.depth()
pass_manager = PassManager(LookaheadSwap(coupling_map=cp))
lc_qc = pass_manager.run(qc)
pass_manager = PassManager(StochasticSwap(coupling_map=cp))
st_qc = pass_manager.run(qc)
depths.append(depth + lc_qc.depth())
depths.append(depth + st_qc.depth())
#print('depth=', depth, ' depth + routing_lc_qc= ', depth + lc_qc.depth(), ' depth + routing_st_qc=',depth + st_qc.depth())
if depths.index(min(depths)) < 2:
print('na')
if show == True:
plot_circuit_layout(new_circ_lv3_na, backend).show()
return new_circ_lv3_na._layout.get_physical_bits()
if depths.index(min(depths)) >= 2:
print('not na')
if show == True:
plot_circuit_layout(new_circ_lv3, backend).show()
return new_circ_lv3._layout.get_physical_bits()
def test_single_gates_omitted(self):
"""Test if single qubit gates are omitted."""
coupling_map = [[0, 1], [1, 0], [1, 2], [1, 3], [2, 1], [3, 1], [3, 4], [4, 3]]
qr = QuantumRegister(5, 'q')
cr = ClassicalRegister(5, 'c')
circuit = QuantumCircuit(qr, cr)
circuit.cx(qr[0], qr[4])
circuit.cx(qr[1], qr[2])
circuit.u3(1, 1.5, 0.7, qr[3])
expected = QuantumCircuit(qr, cr)
expected.cx(qr[1], qr[2])
expected.u3(1, 1.5, 0.7, qr[3])
expected.swap(qr[0], qr[1])
expected.swap(qr[3], qr[4])
expected.cx(qr[1], qr[3])
expected_dag = circuit_to_dag(expected)
stochastic = StochasticSwap(CouplingMap(coupling_map), seed=0)
after = PassManager(stochastic).run(circuit)
after = circuit_to_dag(after)
self.assertEqual(expected_dag, after)
def level_0_pass_manager(
pass_manager_config: PassManagerConfig) -> PassManager:
"""Level 0 pass manager: no explicit optimization other than mapping to backend.
This pass manager applies the user-given initial layout. If none is given, a trivial
layout consisting of mapping the i-th virtual qubit to the i-th physical qubit is used.
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.
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 0 pass manager.
Raises:
TranspilerError: if the passmanager config is invalid.
"""
basis_gates = pass_manager_config.basis_gates
coupling_map = pass_manager_config.coupling_map
initial_layout = pass_manager_config.initial_layout
layout_method = pass_manager_config.layout_method or 'trivial'
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
# 1. Choose an initial layout if not set by user (default: trivial layout)
_given_layout = SetLayout(initial_layout)
def _choose_layout_condition(property_set):
return not property_set['layout']
if layout_method == 'trivial':
_choose_layout = TrivialLayout(coupling_map)
elif layout_method == 'dense':
_choose_layout = DenseLayout(coupling_map, backend_properties)
elif layout_method == 'noise_adaptive':
_choose_layout = NoiseAdaptiveLayout(backend_properties)
elif layout_method == 'sabre':
_choose_layout = SabreLayout(coupling_map,
max_iterations=1,
seed=seed_transpiler)
else:
raise TranspilerError("Invalid layout method %s." % layout_method)
# 2. Extend dag/layout with ancillas using the full coupling map
_embed = [
FullAncillaAllocation(coupling_map),
EnlargeWithAncilla(),
ApplyLayout()
]
# 3. Decompose so only 1-qubit and 2-qubit gates remain
_unroll3q = Unroll3qOrMore()
# 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=2, search_width=2)]
elif routing_method == 'sabre':
_swap += [
SabreSwap(coupling_map, heuristic='basic', seed=seed_transpiler)
]
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 = [
UnrollCustomDefinitions(sel, basis_gates),
BasisTranslator(sel, basis_gates)
]
elif translation_method == 'synthesis':
_unroll = [
Unroll3qOrMore(),
Collect2qBlocks(),
ConsolidateBlocks(basis_gates=basis_gates),
UnitarySynthesis(basis_gates),
]
else:
raise TranspilerError("Invalid translation method %s." %
translation_method)
# 6. Fix any bad CX directions
_direction_check = [CheckCXDirection(coupling_map)]
def _direction_condition(property_set):
return not property_set['is_direction_mapped']
_direction = [CXDirection(coupling_map)]
# 7. Schedule the circuit only when scheduling_method is supplied
if scheduling_method:
_scheduling = [TimeUnitAnalysis(instruction_durations)]
if scheduling_method in {'alap', 'as_late_as_possible'}:
_scheduling += [ALAPSchedule(instruction_durations)]
elif scheduling_method in {'asap', 'as_soon_as_possible'}:
_scheduling += [ASAPSchedule(instruction_durations)]
else:
raise TranspilerError("Invalid scheduling method %s." %
scheduling_method)
# Build pass manager
pm0 = PassManager()
if coupling_map:
pm0.append(_given_layout)
pm0.append(_choose_layout, condition=_choose_layout_condition)
pm0.append(_embed)
pm0.append(_unroll3q)
pm0.append(_swap_check)
pm0.append(_swap, condition=_swap_condition)
pm0.append(_unroll)
if coupling_map and not coupling_map.is_symmetric:
pm0.append(_direction_check)
pm0.append(_direction, condition=_direction_condition)
if scheduling_method:
pm0.append(_scheduling)
return pm0
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_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 fidelitites.
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
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
# 1. 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):
return not property_set['layout']
_choose_layout_1 = CSPLayout(coupling_map, call_limit=1000, time_limit=10)
if layout_method == 'trivial':
_choose_layout_2 = TrivialLayout(coupling_map)
elif layout_method == 'dense':
_choose_layout_2 = DenseLayout(coupling_map, backend_properties)
elif layout_method == 'noise_adaptive':
_choose_layout_2 = NoiseAdaptiveLayout(backend_properties)
elif layout_method == 'sabre':
_choose_layout_2 = SabreLayout(coupling_map, max_iterations=2, seed=seed_transpiler)
else:
raise TranspilerError("Invalid layout method %s." % layout_method)
# 2. Extend dag/layout with ancillas using the full coupling map
_embed = [FullAncillaAllocation(coupling_map), EnlargeWithAncilla(), ApplyLayout()]
# 3. Unroll to 1q or 2q gates
_unroll3q = Unroll3qOrMore()
# 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)]
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 = [UnrollCustomDefinitions(sel, basis_gates),
BasisTranslator(sel, basis_gates)]
elif translation_method == 'synthesis':
_unroll = [
Unroll3qOrMore(),
Collect2qBlocks(),
ConsolidateBlocks(basis_gates=basis_gates),
UnitarySynthesis(basis_gates),
]
else:
raise TranspilerError("Invalid translation method %s." % translation_method)
# 6. Fix any bad CX directions
_direction_check = [CheckCXDirection(coupling_map)]
def _direction_condition(property_set):
return not property_set['is_direction_mapped']
_direction = [CXDirection(coupling_map)]
# 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 = [Optimize1qGates(basis_gates), CommutativeCancellation()]
# 9. Schedule the circuit only when scheduling_method is supplied
if scheduling_method:
_scheduling = [TimeUnitAnalysis(instruction_durations)]
if scheduling_method in {'alap', 'as_late_as_possible'}:
_scheduling += [ALAPSchedule(instruction_durations)]
elif scheduling_method in {'asap', 'as_soon_as_possible'}:
_scheduling += [ASAPSchedule(instruction_durations)]
else:
raise TranspilerError("Invalid scheduling method %s." % scheduling_method)
# Build pass manager
pm2 = PassManager()
if coupling_map:
pm2.append(_given_layout)
pm2.append(_choose_layout_1, condition=_choose_layout_condition)
pm2.append(_choose_layout_2, condition=_choose_layout_condition)
pm2.append(_embed)
pm2.append(_unroll3q)
pm2.append(_swap_check)
pm2.append(_swap, condition=_swap_condition)
pm2.append(_unroll)
if coupling_map and not coupling_map.is_symmetric:
pm2.append(_direction_check)
pm2.append(_direction, condition=_direction_condition)
pm2.append(_reset)
pm2.append(_depth_check + _opt, do_while=_opt_control)
if scheduling_method:
pm2.append(_scheduling)
return pm2
def level_3_pass_manager(pass_manager_config: PassManagerConfig) -> PassManager:
"""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.
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 3 pass manager.
"""
basis_gates = pass_manager_config.basis_gates
coupling_map = pass_manager_config.coupling_map
initial_layout = pass_manager_config.initial_layout
seed_transpiler = pass_manager_config.seed_transpiler
backend_properties = pass_manager_config.backend_properties
# 1. Unroll to the basis first, to prepare for noise-adaptive layout
_unroll = Unroller(basis_gates)
# 2. Layout on good qubits if calibration info available, otherwise on dense links
_given_layout = SetLayout(initial_layout)
def _choose_layout_condition(property_set):
return not property_set['layout']
_choose_layout_1 = CSPLayout(coupling_map, call_limit=10000, time_limit=60)
# TODO: benchmark DenseLayout vs. NoiseAdaptiveLayout in terms of noise aware mapping
_choose_layout_2 = DenseLayout(coupling_map, backend_properties)
# 3. Extend dag/layout with ancillas using the full coupling map
_embed = [FullAncillaAllocation(coupling_map), EnlargeWithAncilla(), ApplyLayout()]
# 4. Unroll to 1q or 2q gates, 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(),
Unroll3qOrMore(),
StochasticSwap(coupling_map, trials=20, seed=seed_transpiler)]
# 5. 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 = [RemoveResetInZeroState(),
Collect2qBlocks(), ConsolidateBlocks(),
Unroller(basis_gates), # unroll unitaries
Optimize1qGates(), CommutativeCancellation(),
OptimizeSwapBeforeMeasure(), RemoveDiagonalGatesBeforeMeasure()]
# 6. Fix any CX direction mismatch
_direction_check = [CheckCXDirection(coupling_map)]
def _direction_condition(property_set):
return not property_set['is_direction_mapped']
_direction = [CXDirection(coupling_map)]
# Build pass manager
pm3 = PassManager()
pm3.append(_unroll)
if coupling_map:
pm3.append(_given_layout)
pm3.append(_choose_layout_1, condition=_choose_layout_condition)
pm3.append(_choose_layout_2, condition=_choose_layout_condition)
pm3.append(_embed)
pm3.append(_swap_check)
pm3.append(_swap, condition=_swap_condition)
pm3.append(_depth_check + _opt, do_while=_opt_control)
if coupling_map and not coupling_map.is_symmetric:
pm3.append(_direction_check)
pm3.append(_direction, condition=_direction_condition)
return pm3
def test_congestion(self):
"""Test code path that falls back to serial layers."""
coupling = CouplingMap([[0, 1], [1, 2], [1, 3]])
qr = QuantumRegister(4, 'q')
cr = ClassicalRegister(4, 'c')
circ = QuantumCircuit(qr, cr)
circ.cx(qr[1], qr[2])
circ.cx(qr[0], qr[3])
circ.measure(qr[0], cr[0])
circ.h(qr)
circ.cx(qr[0], qr[1])
circ.cx(qr[2], qr[3])
circ.measure(qr[0], cr[0])
circ.measure(qr[1], cr[1])
circ.measure(qr[2], cr[2])
circ.measure(qr[3], cr[3])
dag = circuit_to_dag(circ)
# ┌─┐┌───┐ ┌─┐
# q_0: |0>─────────────────■──────────────────┤M├┤ H ├──■─────┤M├
# ┌───┐ │ └╥┘└───┘┌─┴─┐┌─┐└╥┘
# q_1: |0>──■───────┤ H ├──┼───────────────────╫──────┤ X ├┤M├─╫─
# ┌─┴─┐┌───┐└───┘ │ ┌─┐ ║ └───┘└╥┘ ║
# q_2: |0>┤ X ├┤ H ├───────┼─────────■─────┤M├─╫────────────╫──╫─
# └───┘└───┘ ┌─┴─┐┌───┐┌─┴─┐┌─┐└╥┘ ║ ║ ║
# q_3: |0>───────────────┤ X ├┤ H ├┤ X ├┤M├─╫──╫────────────╫──╫─
# └───┘└───┘└───┘└╥┘ ║ ║ ║ ║
# c_0: 0 ═══════════════════════════════╬══╬══╩════════════╬══╩═
# ║ ║ ║
# c_1: 0 ═══════════════════════════════╬══╬═══════════════╩════
# ║ ║
# c_2: 0 ═══════════════════════════════╬══╩════════════════════
# ║
# c_3: 0 ═══════════════════════════════╩═══════════════════════
#
# ┌───┐ ┌───┐ ┌─┐
# q_0: |0>───────X──┤ H ├──────────────────────┤ X ├───┤M├
# │ └───┘┌─┐ ┌───┐ └─┬─┘┌─┐└╥┘
# q_1: |0>──■────X────■──┤M├──────X─┤ X ├─X──────■──┤M├─╫─
# ┌─┴─┐┌───┐ │ └╥┘ │ └─┬─┘ │ ┌─┐ └╥┘ ║
# q_2: |0>┤ X ├┤ H ├──┼───╫───────┼───■───┼─┤M├──────╫──╫─
# └───┘└───┘┌─┴─┐ ║ ┌───┐ │ ┌───┐ │ └╥┘ ┌─┐ ║ ║
# q_3: |0>──────────┤ X ├─╫─┤ H ├─X─┤ H ├─X──╫──┤M├──╫──╫─
# └───┘ ║ └───┘ └───┘ ║ └╥┘ ║ ║
# c_0: 0 ════════════════╩══════════════════╬═══╬═══╩══╬═
# ║ ║ ║
# c_1: 0 ═══════════════════════════════════╬═══╬══════╩═
# ║ ║
# c_2: 0 ═══════════════════════════════════╩═══╬════════
# ║
# c_3: 0 ═══════════════════════════════════════╩════════
#
# 2
# |
# 0 - 1 - 3
expected = QuantumCircuit(qr, cr)
expected.cx(qr[1], qr[2])
expected.h(qr[2])
expected.swap(qr[0], qr[1])
expected.h(qr[0])
expected.cx(qr[1], qr[3])
expected.measure(qr[1], cr[0])
expected.h(qr[3])
expected.swap(qr[1], qr[3])
expected.cx(qr[2], qr[1])
expected.h(qr[3])
expected.swap(qr[1], qr[3])
expected.measure(qr[2], cr[2])
expected.measure(qr[3], cr[3])
expected.cx(qr[1], qr[0])
expected.measure(qr[1], cr[0])
expected.measure(qr[0], cr[1])
expected_dag = circuit_to_dag(expected)
pass_ = StochasticSwap(coupling, 20, 13)
after = pass_.run(dag)
self.assertEqual(expected_dag, after)
def test_overoptimization_case(self):
"""Check mapper overoptimization.
The mapper should not change the semantics of the input.
An overoptimization introduced issue #81:
https://github.com/Qiskit/qiskit-terra/issues/81
"""
coupling = CouplingMap([[0, 2], [1, 2], [2, 3]])
qr = QuantumRegister(4, 'q')
cr = ClassicalRegister(4, 'c')
circuit = QuantumCircuit(qr, cr)
circuit.x(qr[0])
circuit.y(qr[1])
circuit.z(qr[2])
circuit.cx(qr[0], qr[1])
circuit.cx(qr[2], qr[3])
circuit.s(qr[1])
circuit.t(qr[2])
circuit.h(qr[3])
circuit.cx(qr[1], qr[2])
circuit.measure(qr[0], cr[0])
circuit.measure(qr[1], cr[1])
circuit.measure(qr[2], cr[2])
circuit.measure(qr[3], cr[3])
dag = circuit_to_dag(circuit)
# ┌───┐ ┌─┐
# q_0: | 0 >┤ X ├────────────■───────────────────────────┤M├─────────
# └───┘┌───┐ ┌─┴─┐ ┌───┐ └╥┘┌─┐
# q_1: | 0 >─────┤ Y ├─────┤ X ├─────┤ S ├────────────■───╫─┤M├──────
# └───┘┌───┐└───┘ └───┘┌───┐ ┌─┴─┐ ║ └╥┘┌─┐
# q_2: | 0 >──────────┤ Z ├───────■───────┤ T ├─────┤ X ├─╫──╫─┤M├───
# └───┘ ┌─┴─┐ └───┘┌───┐└───┘ ║ ║ └╥┘┌─┐
# q_3: | 0 >────────────────────┤ X ├──────────┤ H ├──────╫──╫──╫─┤M├
# └───┘ └───┘ ║ ║ ║ └╥┘
# c_0: 0 ══════════════════════════════════════════════╩══╬══╬══╬═
# ║ ║ ║
# c_1: 0 ═════════════════════════════════════════════════╩══╬══╬═
# ║ ║
# c_2: 0 ════════════════════════════════════════════════════╩══╬═
# ║
# c_3: 0 ═══════════════════════════════════════════════════════╩═
#
expected = QuantumCircuit(qr, cr)
expected.z(qr[2])
expected.y(qr[1])
expected.x(qr[0])
expected.swap(qr[1], qr[2])
expected.cx(qr[0], qr[2])
expected.swap(qr[2], qr[3])
expected.cx(qr[1], qr[2])
expected.s(qr[3])
expected.t(qr[1])
expected.h(qr[2])
expected.measure(qr[0], cr[0])
expected.swap(qr[1], qr[2])
expected.cx(qr[3], qr[2])
expected.measure(qr[1], cr[3])
expected.measure(qr[3], cr[1])
expected.measure(qr[2], cr[2])
expected_dag = circuit_to_dag(expected)
# ┌───┐ ┌─┐
# q_0: |0>─────────────┤ X ├──■──┤M├────────────────────────────────────────
# ┌───┐ └───┘ │ └╥┘ ┌───┐ ┌───┐┌─┐
# q_1: |0>─────┤ Y ├─X────────┼───╫───────────■──┤ T ├────────┤ X ├┤M├──────
# ┌───┐└───┘ │ ┌─┴─┐ ║ ┌─┴─┐└───┘┌───┐ └─┬─┘└╥┘┌─┐
# q_2: |0>┤ Z ├──────X──────┤ X ├─╫──X──────┤ X ├─────┤ H ├─X───■───╫─┤M├───
# └───┘ └───┘ ║ │ ┌───┐└───┘ └───┘ │ ║ └╥┘┌─┐
# q_3: |0>────────────────────────╫──X─┤ S ├────────────────X───────╫──╫─┤M├
# ║ └───┘ ║ ║ └╥┘
# c_0: 0 ════════════════════════╩═════════════════════════════════╬══╬══╬═
# ║ ║ ║
# c_1: 0 ══════════════════════════════════════════════════════════╬══╩══╬═
# ║ ║
# c_2: 0 ══════════════════════════════════════════════════════════╩═════╬═
# ║
# c_3: 0 ════════════════════════════════════════════════════════════════╩═
#
# Layout --
# {qr[0]: 0,
# qr[1]: 1,
# qr[2]: 2,
# qr[3]: 3}
pass_ = StochasticSwap(coupling, 20, 13)
after = pass_.run(dag)
self.assertEqual(expected_dag, after)
def level_3_pass_manager(
pass_manager_config: PassManagerConfig) -> PassManager:
"""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.
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 3 pass manager.
Raises:
TranspilerError: if the passmanager config is invalid.
"""
basis_gates = pass_manager_config.basis_gates
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
# 1. Unroll to 1q or 2q gates
_unroll3q = Unroll3qOrMore()
# 2. Layout on good qubits if calibration info available, otherwise on dense links
_given_layout = SetLayout(initial_layout)
def _choose_layout_condition(property_set):
return not property_set['layout']
_choose_layout_1 = [] if pass_manager_config.layout_method \
else CSPLayout(coupling_map, call_limit=10000, time_limit=60, seed=seed_transpiler)
if layout_method == 'trivial':
_choose_layout_2 = TrivialLayout(coupling_map)
elif layout_method == 'dense':
_choose_layout_2 = DenseLayout(coupling_map, backend_properties)
elif layout_method == 'noise_adaptive':
_choose_layout_2 = NoiseAdaptiveLayout(backend_properties)
elif layout_method == 'sabre':
_choose_layout_2 = SabreLayout(coupling_map,
max_iterations=4,
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=200, seed=seed_transpiler)
]
elif routing_method == 'lookahead':
_swap += [LookaheadSwap(coupling_map, search_depth=5, search_width=6)]
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 = [
UnrollCustomDefinitions(sel, basis_gates),
BasisTranslator(sel, basis_gates)
]
elif translation_method == 'synthesis':
_unroll = [
Unroll3qOrMore(),
Collect2qBlocks(),
ConsolidateBlocks(basis_gates=basis_gates),
UnitarySynthesis(basis_gates),
]
else:
raise TranspilerError("Invalid translation method %s." %
translation_method)
# 6. Fix any CX direction mismatch
_direction_check = [CheckCXDirection(coupling_map)]
def _direction_condition(property_set):
return not property_set['is_direction_mapped']
_direction = [CXDirection(coupling_map)]
# 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')]
def _opt_control(property_set):
return not property_set['depth_fixed_point']
_reset = [RemoveResetInZeroState()]
_meas = [OptimizeSwapBeforeMeasure(), RemoveDiagonalGatesBeforeMeasure()]
_opt = [
Collect2qBlocks(),
ConsolidateBlocks(basis_gates=basis_gates),
UnitarySynthesis(basis_gates),
Optimize1qGatesDecomposition(basis_gates),
CommutativeCancellation(),
]
# Schedule the circuit only when scheduling_method is supplied
if scheduling_method:
_scheduling = [TimeUnitAnalysis(instruction_durations)]
if scheduling_method in {'alap', 'as_late_as_possible'}:
_scheduling += [ALAPSchedule(instruction_durations)]
elif scheduling_method in {'asap', 'as_soon_as_possible'}:
_scheduling += [ASAPSchedule(instruction_durations)]
else:
raise TranspilerError("Invalid scheduling method %s." %
scheduling_method)
# Build pass manager
pm3 = PassManager()
pm3.append(_unroll3q)
pm3.append(_reset + _meas)
if coupling_map or initial_layout:
pm3.append(_given_layout)
pm3.append(_choose_layout_1, condition=_choose_layout_condition)
pm3.append(_choose_layout_2, condition=_choose_layout_condition)
pm3.append(_embed)
pm3.append(_swap_check)
pm3.append(_swap, condition=_swap_condition)
pm3.append(_unroll)
pm3.append(_depth_check + _opt + _unroll, do_while=_opt_control)
if coupling_map and not coupling_map.is_symmetric:
pm3.append(_direction_check)
pm3.append(_direction, condition=_direction_condition)
pm3.append(_reset)
if scheduling_method:
pm3.append(_scheduling)
return pm3
def test_congestion(self):
"""Test code path that falls back to serial layers."""
coupling = CouplingMap(couplinglist=[[0, 1], [1, 2], [1, 3]])
qr = QuantumRegister(2, 'q')
ar = QuantumRegister(2, 'a')
cr = ClassicalRegister(4, 'c')
circ = QuantumCircuit(qr, ar, cr)
circ.cx(qr[1], ar[0])
circ.cx(qr[0], ar[1])
circ.measure(qr[0], cr[0])
circ.h(qr)
circ.h(ar)
circ.cx(qr[0], qr[1])
circ.cx(ar[0], ar[1])
circ.measure(qr[0], cr[0])
circ.measure(qr[1], cr[1])
circ.measure(ar[0], cr[2])
circ.measure(ar[1], cr[3])
dag = circuit_to_dag(circ)
# ┌─┐┌───┐ ┌─┐
# q_0: |0>─────────────────■──────────────────┤M├┤ H ├──■─────┤M├
# ┌───┐ │ └╥┘└───┘┌─┴─┐┌─┐└╥┘
# q_1: |0>──■───────┤ H ├──┼───────────────────╫──────┤ X ├┤M├─╫─
# ┌─┴─┐┌───┐└───┘ │ ┌─┐ ║ └───┘└╥┘ ║
# a_0: |0>┤ X ├┤ H ├───────┼─────────■─────┤M├─╫────────────╫──╫─
# └───┘└───┘ ┌─┴─┐┌───┐┌─┴─┐┌─┐└╥┘ ║ ║ ║
# a_1: |0>───────────────┤ X ├┤ H ├┤ X ├┤M├─╫──╫────────────╫──╫─
# └───┘└───┘└───┘└╥┘ ║ ║ ║ ║
# c_0: 0 ═══════════════════════════════╬══╬══╩════════════╬══╩═
# ║ ║ ║
# c_1: 0 ═══════════════════════════════╬══╬═══════════════╩════
# ║ ║
# c_2: 0 ═══════════════════════════════╬══╩════════════════════
# ║
# c_3: 0 ═══════════════════════════════╩═══════════════════════
#
# ┌─┐┌───┐ ┌─┐
# q_0: |0>────────────────────■──┤M├┤ H ├──────────────────■──┤M├──────
# ┌─┴─┐└╥┘└───┘┌───┐┌───┐ ┌─┴─┐└╥┘┌─┐
# q_1: |0>──■───X───────────┤ X ├─╫──────┤ H ├┤ X ├─X────┤ X ├─╫─┤M├───
# ┌─┴─┐ │ ┌───┐└───┘ ║ └───┘└─┬─┘ │ └───┘ ║ └╥┘┌─┐
# a_0: |0>┤ X ├─┼──────┤ H ├──────╫─────────────■───┼──────────╫──╫─┤M├
# └───┘ │ ┌───┐└───┘ ║ │ ┌─┐ ║ ║ └╥┘
# a_1: |0>──────X─┤ H ├───────────╫─────────────────X─┤M├──────╫──╫──╫─
# └───┘ ║ └╥┘ ║ ║ ║
# c_0: 0 ════════════════════════╩════════════════════╬═══════╩══╬══╬═
# ║ ║ ║
# c_1: 0 ═════════════════════════════════════════════╬══════════╩══╬═
# ║ ║
# c_2: 0 ═════════════════════════════════════════════╬═════════════╩═
# ║
# c_3: 0 ═════════════════════════════════════════════╩═══════════════
#
# Layout from mapper:
# {(QuantumRegister(2, 'q'), 0): 0,
# (QuantumRegister(2, 'q'), 1): 1,
# (QuantumRegister(2, 'a'), 0): 2,
# (QuantumRegister(2, 'a'), 1): 3}
#
# 2
# |
# 0 - 1 - 3
expected = QuantumCircuit(qr, ar, cr)
expected.cx(qr[1], ar[0])
expected.h(ar[0])
expected.swap(qr[1], ar[1])
expected.cx(qr[0], qr[1])
expected.h(ar[1])
expected.h(qr[1])
expected.cx(ar[0], qr[1])
expected.measure(qr[0], cr[0])
expected.h(qr[0])
expected.measure(ar[0], cr[2])
expected.swap(ar[1], qr[1])
expected.cx(qr[0], qr[1])
expected.measure(ar[1], cr[3])
expected.measure(qr[1], cr[1])
expected.measure(qr[0], cr[0])
expected_dag = circuit_to_dag(expected)
layout = Layout([(QuantumRegister(2, 'q'), 0),
(QuantumRegister(2, 'q'), 1),
(QuantumRegister(2, 'a'), 0),
(QuantumRegister(2, 'a'), 1)])
pass_ = StochasticSwap(coupling, layout, 20, 13)
after = pass_.run(dag)
self.assertEqual(expected_dag, after)
# # # 2 # | # 0 - 1 - 3 # Build the expected output to verify the pass worked expected = QuantumCircuit(qr, cr) expected.cx(qr[1], qr[2]) expected.swap(qr[0], qr[1]) expected.cx(qr[1], qr[3]) expected.h(qr[3]) expected.h(qr[2]) expected.measure(qr[1], cr[0]) expected.h(qr[0]) expected.swap(qr[1], qr[3]) expected.h(qr[3]) expected.cx(qr[2], qr[1]) expected.measure(qr[2], cr[2]) expected.swap(qr[1], qr[3]) expected.measure(qr[3], cr[3]) expected.cx(qr[1], qr[0]) expected.measure(qr[1], cr[0]) expected.measure(qr[0], cr[1]) expected_dag = circuit_to_dag(expected) # Run the pass on the dag from the input circuit pass_ = StochasticSwap(coupling, 20, 999) after = pass_.run(dag) # Verify the output of the pass matches our expectation assert expected_dag == after
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
_given_layout = SetLayout(initial_layout)
_choose_layout_and_score = [
TrivialLayout(coupling_map),
Layout2qDistance(coupling_map, property_name="trivial_layout_score"),
]
def _choose_layout_condition(property_set):
return not property_set["layout"]
# 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,
),
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)
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)
def _not_perfect_yet(property_set):
return (property_set["trivial_layout_score"] is not None
and property_set["trivial_layout_score"] != 0)
# 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,
),
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,
),
Unroll3qOrMore(),
Collect2qBlocks(),
ConsolidateBlocks(basis_gates=basis_gates),
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,
),
]
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
_depth_check = [Depth(), FixedPoint("depth")]
def _opt_control(property_set):
return not property_set["depth_fixed_point"]
_opt = [Optimize1qGatesDecomposition(basis_gates), CXCancellation()]
# 10. 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)]
elif scheduling_method in {"asap", "as_soon_as_possible"}:
_scheduling += [ASAPSchedule(instruction_durations)]
else:
raise TranspilerError("Invalid scheduling method %s." %
scheduling_method)
# 11. 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
pm1 = PassManager()
if coupling_map or initial_layout:
pm1.append(_given_layout)
pm1.append(_unroll3q)
pm1.append(_choose_layout_and_score,
condition=_choose_layout_condition)
pm1.append(_improve_layout, condition=_not_perfect_yet)
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 + _opt + _unroll, do_while=_opt_control)
if inst_map and inst_map.has_custom_gate():
pm1.append(PulseGates(inst_map=inst_map))
if scheduling_method:
pm1.append(_scheduling)
elif instruction_durations:
pm1.append(_time_unit_setup)
pm1.append(_time_unit_conversion, condition=_contains_delay)
pm1.append(_alignments)
return pm1
def noise_pass_manager(basis_gates=None,
initial_layout=None,
coupling_map=None,
layout_method=None,
translation_method=None,
seed_transpiler=None,
backend=None,
routing_method=None,
backend_properties=None,
transform=False,
readout=True,
alpha=0.5,
next_gates=5,
front=True) -> PassManager:
"""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.
Note:
In simulators where ``coupling_map=None``, only the unrolling and
optimization stages are done.
Args:
backend (BaseBackend)
Returns:
a level 3 pass manager.
Raises:
TranspilerError: if the passmanager config is invalid.
"""
if basis_gates is None:
if getattr(backend, 'configuration', None):
basis_gates = getattr(backend.configuration(), 'basis_gates', None)
# basis_gates could be None, or a list of basis, e.g. ['u3', 'cx']
if isinstance(basis_gates, list) and all(
isinstance(i, str) for i in basis_gates):
basis_gates = basis_gates
if basis_gates is None:
basis_gates = ['u3', 'cx', 'id']
# basis_gates = ['u3', 'cx', 'id']
backend = backend
if backend is None or backend.configuration().simulator:
if backend_properties is None or coupling_map is None:
raise QiskitError(
"Backend is simulator or not specified, provide backend properties and coupling map."
)
coupling_map = coupling_map
backend_properties = backend_properties
else:
if backend_properties is not None or coupling_map is not None:
warnings.warn(
"A backend was provide, ignoring backend properties and coupling map",
UserWarning)
coupling_map = backend.configuration().coupling_map
backend_properties = backend.properties()
if isinstance(coupling_map, list):
coupling_map = CouplingMap(couplinglist=coupling_map)
initial_layout = initial_layout
layout_method = layout_method or 'dense'
routing_method = routing_method or 'stochastic'
translation_method = translation_method or 'translator'
seed_transpiler = seed_transpiler
# 1. Unroll to 1q or 2q gates
_unroll3q = Unroll3qOrMore()
# 2. Layout on good qubits if calibration info available, otherwise on dense links
_given_layout = SetLayout(initial_layout)
def _choose_layout_condition(property_set):
return not property_set['layout']
_choose_layout_1 = CSPLayout(coupling_map, call_limit=10000, time_limit=60)
if layout_method == 'trivial':
_choose_layout_2 = TrivialLayout(coupling_map)
elif layout_method == 'dense':
_choose_layout_2 = DenseLayout(coupling_map, backend_properties)
elif layout_method == 'noise_adaptive':
_choose_layout_2 = NoiseAdaptiveLayout(backend_properties)
elif layout_method == 'sabre':
_choose_layout_2 = SabreLayout(coupling_map,
max_iterations=4,
seed=seed_transpiler)
elif layout_method == 'chain':
_choose_layout_2 = ChainLayout(coupling_map,
backend_properties,
readout=readout)
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=200, seed=seed_transpiler)
]
elif routing_method == 'lookahead':
_swap += [LookaheadSwap(coupling_map, search_depth=5, search_width=6)]
elif routing_method == 'sabre':
_swap += [
SabreSwap(coupling_map, heuristic='decay', seed=seed_transpiler)
]
elif routing_method == 'noise_adaptive':
_swap += [
NoiseAdaptiveSwap(coupling_map,
backend_properties,
invert_score=invert_score,
swap_score=swap_score,
readout=readout,
alpha=alpha,
next_gates=next_gates,
front=front)
]
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 = [
UnrollCustomDefinitions(sel, basis_gates),
BasisTranslator(sel, basis_gates)
]
elif translation_method == 'synthesis':
_unroll = [
Unroll3qOrMore(),
Collect2qBlocks(),
ConsolidateBlocks(basis_gates=basis_gates),
UnitarySynthesis(basis_gates),
]
else:
raise TranspilerError("Invalid translation method %s." %
translation_method)
# 6. Fix any CX direction mismatch
_direction_check = [CheckCXDirection(coupling_map)]
def _direction_condition(property_set):
return not property_set['is_direction_mapped']
_direction = [CXDirection(coupling_map)]
# 8. Optimize iteratively until no more change in depth. Removes useless gates
# after reset and before measure, commutes gates and optimizes continguous blocks.
_depth_check = [Depth(), FixedPoint('depth')]
def _opt_control(property_set):
return not property_set['depth_fixed_point']
_reset = [RemoveResetInZeroState()]
_meas = [OptimizeSwapBeforeMeasure(), RemoveDiagonalGatesBeforeMeasure()]
_opt = [
Collect2qBlocks(),
ConsolidateBlocks(basis_gates=basis_gates),
UnitarySynthesis(basis_gates),
Optimize1qGates(basis_gates),
CommutativeCancellation(),
]
# Build pass manager
pm3 = PassManager()
pm3.append(_unroll3q)
if transform:
_transform = TransformCxCascade()
pm3.append(_transform)
pm3.append(_reset + _meas)
if coupling_map:
pm3.append(_given_layout)
pm3.append(_choose_layout_1, condition=_choose_layout_condition)
pm3.append(_choose_layout_2, condition=_choose_layout_condition)
pm3.append(_embed)
pm3.append(_swap_check)
pm3.append(_swap, condition=_swap_condition)
pm3.append(_unroll)
pm3.append(_depth_check + _opt + _unroll, do_while=_opt_control)
if coupling_map and not coupling_map.is_symmetric:
pm3.append(_direction_check)
pm3.append(_direction, condition=_direction_condition)
pm3.append(_reset)
return pm3
def level_1_pass_manager(pass_manager_config):
"""
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 (PassManagerConfig)
Returns:
PassManager: a level 1 pass manager.
"""
basis_gates = pass_manager_config.basis_gates
coupling_map = pass_manager_config.coupling_map
initial_layout = pass_manager_config.initial_layout
seed_transpiler = pass_manager_config.seed_transpiler
backend_properties = pass_manager_config.backend_properties
# 1. Use trivial layout if no layout given
_set_initial_layout = SetLayout(initial_layout)
def _choose_layout_condition(property_set):
return not property_set['layout']
# 2. Use a better layout on densely connected qubits, if circuit needs swaps
def _not_perfect_yet(property_set):
return property_set['trivial_layout_score'] is not None and \
property_set['trivial_layout_score'] != 0
# 3. Extend dag/layout with ancillas using the full coupling map
_embed = [
FullAncillaAllocation(coupling_map),
EnlargeWithAncilla(),
ApplyLayout()
]
# 4. Unroll to the basis
_unroll = Unroller(basis_gates)
# 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(),
Unroll3qOrMore(),
StochasticSwap(coupling_map, trials=20, seed=seed_transpiler),
Decompose(SwapGate)
]
# 6. Fix any bad CX directions
_direction_check = [CheckCXDirection(coupling_map)]
def _direction_condition(property_set):
return not property_set['is_direction_mapped']
_direction = [CXDirection(coupling_map)]
# 7. Remove zero-state reset
_reset = RemoveResetInZeroState()
# 8. Merge 1q rotations and cancel CNOT gates 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 = [Optimize1qGates(), CXCancellation()]
pm1 = PassManager()
if coupling_map:
pm1.append(_set_initial_layout)
pm1.append([
TrivialLayout(coupling_map),
Layout2qDistance(coupling_map,
property_name='trivial_layout_score')
],
condition=_choose_layout_condition)
pm1.append(DenseLayout(coupling_map, backend_properties),
condition=_not_perfect_yet)
pm1.append(_embed)
pm1.append(_unroll)
if coupling_map:
pm1.append(_swap_check)
pm1.append(_swap, condition=_swap_condition)
if not coupling_map.is_symmetric:
pm1.append(_direction_check)
pm1.append(_direction, condition=_direction_condition)
pm1.append(_reset)
pm1.append(_depth_check + _opt, do_while=_opt_control)
return pm1
def level_3_pass_manager(pass_manager_config: PassManagerConfig) -> PassManager:
"""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.
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 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
# 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,
plugin_config=unitary_synthesis_plugin_config,
min_qubits=3,
),
Unroll3qOrMore(),
]
# 2. 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 _csp_not_found_match(property_set):
# If a layout hasn't been set by the time we run csp we need to run layout
if property_set["layout"] is None:
return True
# if CSP layout stopped for any reason other than solution found we need
# to run layout since CSP didn't converge.
if (
property_set["CSPLayout_stop_reason"] is not None
and property_set["CSPLayout_stop_reason"] != "solution found"
):
return True
return False
# 2a. If layout method is not set, first try a trivial layout
_choose_layout_0 = (
[]
if pass_manager_config.layout_method
else [
TrivialLayout(coupling_map),
Layout2qDistance(coupling_map, property_name="trivial_layout_score"),
]
)
# 2b. If trivial layout wasn't perfect (ie no swaps are needed) then try
# using CSP layout to find a perfect layout
_choose_layout_1 = (
[]
if pass_manager_config.layout_method
else CSPLayout(coupling_map, call_limit=10000, time_limit=60, seed=seed_transpiler)
)
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 property set is unconditionally
# set by trivial layout so we clear that before running CSP
if property_set["trivial_layout_score"] is not None:
if property_set["trivial_layout_score"] != 0:
return True
return False
# 2c. if CSP didn't converge on a solution use layout_method (dense).
if layout_method == "trivial":
_choose_layout_2 = TrivialLayout(coupling_map)
elif layout_method == "dense":
_choose_layout_2 = DenseLayout(coupling_map, backend_properties)
elif layout_method == "noise_adaptive":
_choose_layout_2 = NoiseAdaptiveLayout(backend_properties)
elif layout_method == "sabre":
_choose_layout_2 = SabreLayout(coupling_map, max_iterations=4, 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=200, seed=seed_transpiler)]
elif routing_method == "lookahead":
_swap += [LookaheadSwap(coupling_map, search_depth=5, search_width=6)]
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 = [
UnitarySynthesis(
basis_gates,
approximation_degree=approximation_degree,
coupling_map=coupling_map,
backend_props=backend_properties,
plugin_config=unitary_synthesis_plugin_config,
method=unitary_synthesis_method,
),
UnrollCustomDefinitions(sel, basis_gates),
BasisTranslator(sel, basis_gates, target),
]
elif translation_method == "synthesis":
_unroll = [
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),
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 CX direction mismatch
_direction_check = [CheckGateDirection(coupling_map, target)]
def _direction_condition(property_set):
return not property_set["is_direction_mapped"]
_direction = [GateDirection(coupling_map, target)]
# 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")]
def _opt_control(property_set):
return not property_set["depth_fixed_point"]
_reset = [RemoveResetInZeroState()]
_meas = [OptimizeSwapBeforeMeasure(), RemoveDiagonalGatesBeforeMeasure()]
_opt = [
Collect2qBlocks(),
ConsolidateBlocks(basis_gates=basis_gates),
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,
),
Optimize1qGatesDecomposition(basis_gates),
CommutativeCancellation(),
]
# 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)]
elif scheduling_method in {"asap", "as_soon_as_possible"}:
_scheduling += [ASAPSchedule(instruction_durations)]
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
pm3 = PassManager()
pm3.append(_unroll3q)
pm3.append(_reset + _meas)
if coupling_map or initial_layout:
pm3.append(_given_layout)
pm3.append(_choose_layout_0, condition=_choose_layout_condition)
pm3.append(_choose_layout_1, condition=_trivial_not_perfect)
pm3.append(_choose_layout_2, condition=_csp_not_found_match)
pm3.append(_embed)
pm3.append(_swap_check)
pm3.append(_swap, condition=_swap_condition)
pm3.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)
):
pm3.append(_direction_check)
pm3.append(_direction, condition=_direction_condition)
pm3.append(_reset)
# 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:
pm3.append(_depth_check + _opt + _unroll + _direction, do_while=_opt_control)
else:
pm3.append(_depth_check + _opt + _unroll, do_while=_opt_control)
else:
pm3.append(_reset)
pm3.append(_depth_check + _opt + _unroll, do_while=_opt_control)
if inst_map and inst_map.has_custom_gate():
pm3.append(PulseGates(inst_map=inst_map))
if scheduling_method:
pm3.append(_scheduling)
elif instruction_durations:
pm3.append(_time_unit_setup)
pm3.append(_time_unit_conversion, condition=_contains_delay)
pm3.append(_alignments)
return pm3
def level_0_pass_manager(pass_manager_config):
"""
Level 0 pass manager: no explicit optimization other than mapping to backend.
This pass manager applies the user-given initial layout. If none is given, a trivial
layout consisting of mapping the i-th virtual qubit to the i-th physical qubit is used.
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, extra resets are removed.
Note: in simulators where coupling_map=None, only the unrolling and optimization
stages are done.
Args:
pass_manager_config (PassManagerConfig)
Returns:
PassManager: a level 0 pass manager.
"""
basis_gates = pass_manager_config.basis_gates
coupling_map = pass_manager_config.coupling_map
initial_layout = pass_manager_config.initial_layout
seed_transpiler = pass_manager_config.seed_transpiler
# 1. Use trivial layout if no layout given
_given_layout = SetLayout(initial_layout)
def _choose_layout_condition(property_set):
return not property_set['layout']
_choose_layout = TrivialLayout(coupling_map)
# 2. Extend dag/layout with ancillas using the full coupling map
_embed = [
FullAncillaAllocation(coupling_map),
EnlargeWithAncilla(),
ApplyLayout()
]
# 3. Unroll to the basis
_unroll = Unroller(basis_gates)
# 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(),
StochasticSwap(coupling_map, trials=20, seed=seed_transpiler),
Decompose(SwapGate)
]
# 5. Fix any bad CX directions
_direction_check = [CheckCXDirection(coupling_map)]
def _direction_condition(property_set):
return not property_set['is_direction_mapped']
_direction = [CXDirection(coupling_map)]
# 6. Remove zero-state reset
_reset = RemoveResetInZeroState()
pm0 = PassManager()
if coupling_map:
pm0.append(_given_layout)
pm0.append(_choose_layout, condition=_choose_layout_condition)
pm0.append(_embed)
pm0.append(_unroll)
if coupling_map:
pm0.append(_swap_check)
pm0.append(_swap, condition=_swap_condition)
if not coupling_map.is_symmetric:
pm0.append(_direction_check)
pm0.append(_direction, condition=_direction_condition)
pm0.append(_reset)
return pm0
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 fidelitites.
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.
"""
basis_gates = pass_manager_config.basis_gates
coupling_map = pass_manager_config.coupling_map
initial_layout = pass_manager_config.initial_layout
seed_transpiler = pass_manager_config.seed_transpiler
backend_properties = pass_manager_config.backend_properties
# 1. 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):
return not property_set['layout']
_choose_layout_1 = CSPLayout(coupling_map, call_limit=1000, time_limit=10)
_choose_layout_2 = DenseLayout(coupling_map, backend_properties)
# 2. Extend dag/layout with ancillas using the full coupling map
_embed = [
FullAncillaAllocation(coupling_map),
EnlargeWithAncilla(),
ApplyLayout()
]
# 3. Unroll to 1q or 2q gates
_unroll3q = Unroll3qOrMore()
# 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(),
StochasticSwap(coupling_map, trials=20, seed=seed_transpiler)
]
# 5. Unroll to the basis
_unroll = Unroller(basis_gates)
# 6. Fix any bad CX directions
_direction_check = [CheckCXDirection(coupling_map)]
def _direction_condition(property_set):
return not property_set['is_direction_mapped']
_direction = [CXDirection(coupling_map)]
# 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 = [Optimize1qGates(), CommutativeCancellation()]
# Build pass manager
pm2 = PassManager()
if coupling_map:
pm2.append(_given_layout)
pm2.append(_choose_layout_1, condition=_choose_layout_condition)
pm2.append(_choose_layout_2, condition=_choose_layout_condition)
pm2.append(_embed)
pm2.append(_unroll3q)
pm2.append(_swap_check)
pm2.append(_swap, condition=_swap_condition)
pm2.append(_unroll)
if coupling_map and not coupling_map.is_symmetric:
pm2.append(_direction_check)
pm2.append(_direction, condition=_direction_condition)
pm2.append(_reset)
pm2.append(_depth_check + _opt, do_while=_opt_control)
return pm2
def level_3_pass_manager(transpile_config):
"""
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, and
device calibration information is available, the circuit is mapped to the qubits
with best readouts and to CX gates with highest fidelity. Otherwise, a layout on
the most densely connected qubits is used.
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.
Note: in simulators where coupling_map=None, only the unrolling and optimization
stages are done.
Args:
transpile_config (TranspileConfig)
Returns:
PassManager: a level 3 pass manager.
"""
basis_gates = transpile_config.basis_gates
coupling_map = transpile_config.coupling_map
initial_layout = transpile_config.initial_layout
seed_transpiler = transpile_config.seed_transpiler
backend_properties = transpile_config.backend_properties
# 1. Unroll to the basis first, to prepare for noise-adaptive layout
_unroll = Unroller(basis_gates)
# 2. Layout on good qubits if calibration info available, otherwise on dense links
_given_layout = SetLayout(initial_layout)
def _choose_layout_condition(property_set):
return not property_set['layout']
_choose_layout = DenseLayout(coupling_map)
if backend_properties:
_choose_layout = NoiseAdaptiveLayout(backend_properties)
# 3. Extend dag/layout with ancillas using the full coupling map
_embed = [
FullAncillaAllocation(coupling_map),
EnlargeWithAncilla(),
ApplyLayout()
]
# 4. Unroll to 1q or 2q gates, 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(),
Unroll3qOrMore(),
StochasticSwap(coupling_map, trials=20, seed=seed_transpiler),
Decompose(SwapGate)
]
_direction_check = [CheckCXDirection(coupling_map)]
def _direction_condition(property_set):
return not property_set['is_direction_mapped']
_direction = [CXDirection(coupling_map)]
# 5. 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 = [
RemoveResetInZeroState(),
Collect2qBlocks(),
ConsolidateBlocks(),
Unroller(basis_gates), # unroll unitaries
Optimize1qGates(),
CommutativeCancellation(),
OptimizeSwapBeforeMeasure(),
RemoveDiagonalGatesBeforeMeasure()
]
if coupling_map:
_opt.append(CXDirection(coupling_map))
# if a coupling map has been provided, match coupling
pm3 = PassManager()
pm3.append(_unroll)
if coupling_map:
pm3.append(_given_layout)
pm3.append(_choose_layout, condition=_choose_layout_condition)
pm3.append(_embed)
pm3.append(_swap_check)
pm3.append(_swap, condition=_swap_condition)
if not coupling_map.is_symmetric:
pm3.append(_direction_check)
pm3.append(_direction, condition=_direction_condition)
pm3.append(_depth_check + _opt, do_while=_opt_control)
return pm3
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
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'
seed_transpiler = pass_manager_config.seed_transpiler
backend_properties = pass_manager_config.backend_properties
# 1. Use trivial layout if no layout given
_given_layout = SetLayout(initial_layout)
_choose_layout_and_score = [
TrivialLayout(coupling_map),
Layout2qDistance(coupling_map, property_name='trivial_layout_score')
]
def _choose_layout_condition(property_set):
return not property_set['layout']
# 2. 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)
elif layout_method == 'noise_adaptive':
_improve_layout = NoiseAdaptiveLayout(backend_properties)
else:
raise TranspilerError("Invalid layout method %s." % layout_method)
def _not_perfect_yet(property_set):
return property_set['trivial_layout_score'] is not None and \
property_set['trivial_layout_score'] != 0
# 3. Extend dag/layout with ancillas using the full coupling map
_embed = [
FullAncillaAllocation(coupling_map),
EnlargeWithAncilla(),
ApplyLayout()
]
# 4. Decompose so only 1-qubit and 2-qubit gates remain
_unroll3q = Unroll3qOrMore()
# 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)]
else:
raise TranspilerError("Invalid routing method %s." % routing_method)
# 6. Unroll to the basis
_unroll = Unroller(basis_gates)
# 7. Fix any bad CX directions
_direction_check = [CheckCXDirection(coupling_map)]
def _direction_condition(property_set):
return not property_set['is_direction_mapped']
_direction = [CXDirection(coupling_map)]
# 8. Remove zero-state reset
_reset = RemoveResetInZeroState()
# 9. Merge 1q rotations and cancel CNOT gates 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 = [Optimize1qGates(basis_gates), CXCancellation()]
# Build pass manager
pm1 = PassManager()
if coupling_map:
pm1.append(_given_layout)
pm1.append(_choose_layout_and_score,
condition=_choose_layout_condition)
pm1.append(_improve_layout, condition=_not_perfect_yet)
pm1.append(_embed)
pm1.append(_unroll3q)
pm1.append(_swap_check)
pm1.append(_swap, condition=_swap_condition)
pm1.append(_unroll)
if coupling_map and not coupling_map.is_symmetric:
pm1.append(_direction_check)
pm1.append(_direction, condition=_direction_condition)
pm1.append(_reset)
pm1.append(_depth_check + _opt, do_while=_opt_control)
return pm1
