def test_ccz():
before = cirq.Circuit(
cirq.CCZ(cirq.GridQubit(5, 5), cirq.GridQubit(5, 6),
cirq.GridQubit(5, 7)))
after = cg.optimized_for_xmon(before)
assert len(after) <= 22
assert_circuits_with_terminal_measurements_are_equivalent(before,
after,
atol=1e-4)
def test_remap_qubits():
before = cirq.Circuit(
[cirq.Moment([cirq.CZ(cirq.LineQubit(0), cirq.LineQubit(1))])])
after = cg.optimized_for_xmon(before,
new_device=cg.Foxtail,
qubit_map=lambda q: cirq.GridQubit(q.x, 0))
assert after == cirq.Circuit(
[cirq.Moment([cirq.CZ(cirq.GridQubit(0, 0), cirq.GridQubit(1, 0))])],
device=cg.Foxtail)
def test_ccz():
before = cirq.Circuit.from_ops(
cirq.CCZ(cirq.GridQubit(5, 5),
cirq.GridQubit(5, 6),
cirq.GridQubit(5, 7)))
after = cg.optimized_for_xmon(before)
assert len(after) <= 22
assert_circuits_with_terminal_measurements_are_equivalent(
before, after, atol=1e-4)
def test_swap_field(n: int, d: int):
before = cirq.Circuit(
cirq.ISWAP(cirq.LineQubit(j), cirq.LineQubit(j + 1)) for i in range(d)
for j in range(i % 2, n - 1, 2))
before.append(cirq.measure(*before.all_qubits()))
after = cg.optimized_for_xmon(before)
assert len(after) == d * 4 + 2
if n <= 5:
assert_circuits_with_terminal_measurements_are_equivalent(before,
after,
atol=1e-4)
def test_remap_qubits():
before = cirq.Circuit([cirq.Moment([
cirq.CZ(cirq.LineQubit(0), cirq.LineQubit(1))])])
after = cg.optimized_for_xmon(before,
new_device=cg.Foxtail,
qubit_map=lambda q: cirq.GridQubit(q.x, 0))
assert after == cirq.Circuit([
cirq.Moment([
cg.Exp11Gate().on(cirq.GridQubit(0, 0), cirq.GridQubit(1, 0))])],
device=cg.Foxtail)
def test_dont_allow_partial_czs():
before = cirq.Circuit([cirq.Moment([
cirq.CZ(cirq.GridQubit(5, 5), cirq.GridQubit(5, 6)) ** 0.5])])
after = cg.optimized_for_xmon(before, allow_partial_czs=False)
cz_gates = [op.gate for op in after.all_operations()
if isinstance(op, cirq.GateOperation) and
isinstance(op.gate, cirq.Rot11Gate)]
num_full_cz = sum(1 for cz in cz_gates if cz.half_turns == 1)
num_part_cz = sum(1 for cz in cz_gates if cz.half_turns != 1)
assert num_full_cz == 2
assert num_part_cz == 0
def test_dont_allow_partial_czs():
before = cirq.Circuit([cirq.Moment([
cirq.CZ(cirq.GridQubit(5, 5), cirq.GridQubit(5, 6)) ** 0.5])])
after = cg.optimized_for_xmon(before, allow_partial_czs=False)
cz_gates = [op.gate for op in after.all_operations()
if cg.XmonGate.is_xmon_op(op) and
isinstance(op.gate, cg.Exp11Gate)]
num_full_cz = sum(1 for cz in cz_gates if cz.half_turns == 1)
num_part_cz = sum(1 for cz in cz_gates if cz.half_turns != 1)
assert num_full_cz == 2
assert num_part_cz == 0
def test_adjacent_cz_get_split_apart():
before = cirq.Circuit([cirq.Moment([
cirq.CZ(cirq.GridQubit(0, 0), cirq.GridQubit(0, 1)),
cirq.CZ(cirq.GridQubit(1, 0), cirq.GridQubit(1, 1))])])
after = cg.optimized_for_xmon(before,
new_device=cg.Foxtail)
assert after == cirq.Circuit([
cirq.Moment([
cirq.CZ(cirq.GridQubit(0, 0), cirq.GridQubit(0, 1))]),
cirq.Moment([
cirq.CZ(cirq.GridQubit(1, 0), cirq.GridQubit(1, 1))])],
device=cg.Foxtail)
def test_adjacent_cz_get_split_apart():
before = cirq.Circuit([cirq.Moment([
cirq.CZ(cirq.GridQubit(0, 0), cirq.GridQubit(0, 1)),
cirq.CZ(cirq.GridQubit(1, 0), cirq.GridQubit(1, 1))])])
after = cg.optimized_for_xmon(before,
new_device=cg.Foxtail)
assert after == cirq.Circuit([
cirq.Moment([
cg.Exp11Gate().on(cirq.GridQubit(0, 0), cirq.GridQubit(0, 1))]),
cirq.Moment([
cg.Exp11Gate().on(cirq.GridQubit(1, 0), cirq.GridQubit(1, 1))])],
device=cg.Foxtail)
def test_swap_field(n: int, d: int):
before = cirq.Circuit.from_ops(
cirq.ISWAP(cirq.LineQubit(j), cirq.LineQubit(j + 1))
for i in range(d)
for j in range(i % 2, n - 1, 2)
)
before.append(cirq.measure(*before.all_qubits()))
after = cg.optimized_for_xmon(before)
assert len(after) == d*4 + 2
if n <= 5:
assert_circuits_with_terminal_measurements_are_equivalent(
before, after, atol=1e-4)
def test_allow_partial_czs():
before = cirq.Circuit([
cirq.Moment([cirq.CZ(cirq.GridQubit(5, 5), cirq.GridQubit(5, 6))**0.5])
])
after = cg.optimized_for_xmon(before, allow_partial_czs=True)
cz_gates = [
op.gate for op in after.all_operations()
if isinstance(op, cirq.GateOperation)
and isinstance(op.gate, cirq.CZPowGate)
]
num_full_cz = sum(1 for cz in cz_gates if cz.exponent % 2 == 1)
num_part_cz = sum(1 for cz in cz_gates if cz.exponent % 2 != 1)
assert num_full_cz == 0
assert num_part_cz == 1
def converted_gate_set(circuit: circuits.Circuit, atol: float = 1e-7
) -> circuits.Circuit:
"""Returns a new, equivalent circuit using the gate set {CliffordGate,
PauliInteractionGate, PauliStringPhasor}.
The circuit structure may differ because it is optimized during conversion.
"""
xmon_circuit = google.optimized_for_xmon(circuit, allow_partial_czs=False)
qubits = circuit.all_qubits()
tol = linalg.Tolerance(atol=atol)
def is_clifford_rotation(half_turns):
return tol.all_near_zero_mod(half_turns, 0.5)
def to_quarter_turns(half_turns):
return round(2 * half_turns) % 4
def is_quarter_turn(half_turns):
return (is_clifford_rotation(half_turns) and
to_quarter_turns(half_turns) % 2 == 1)
def is_half_turn(half_turns):
return (is_clifford_rotation(half_turns) and
to_quarter_turns(half_turns) == 2)
def is_no_turn(half_turns):
return (is_clifford_rotation(half_turns) and
to_quarter_turns(half_turns) == 0)
def rotation_to_clifford_op(pauli, qubit, half_turns):
quarter_turns = to_quarter_turns(half_turns)
if quarter_turns == 0:
return ops.CliffordGate.I(qubit)
elif quarter_turns == 2:
return ops.CliffordGate.from_pauli(pauli)(qubit)
else:
gate = ops.CliffordGate.from_pauli(pauli, True)(qubit)
if quarter_turns == 3:
gate = gate.inverse()
return gate
def rotation_to_non_clifford_op(pauli, qubit, half_turns):
return PauliStringPhasor(ops.PauliString.from_single(qubit, pauli),
half_turns=half_turns)
def single_qubit_matrix_to_ops(mat, qubit):
# Decompose matrix
z_rad_before, y_rad, z_rad_after = (
linalg.deconstruct_single_qubit_matrix_into_angles(mat))
z_ht_before = z_rad_before / np.pi - 0.5
m_ht = y_rad / np.pi
m_pauli = ops.Pauli.X
z_ht_after = z_rad_after / np.pi + 0.5
# Clean up angles
if is_clifford_rotation(z_ht_before):
if is_quarter_turn(z_ht_before) or is_quarter_turn(z_ht_after):
z_ht_before += 0.5
z_ht_after -= 0.5
m_pauli = ops.Pauli.Y
if is_half_turn(z_ht_before) or is_half_turn(z_ht_after):
z_ht_before -= 1
z_ht_after += 1
m_ht = -m_ht
if is_no_turn(m_ht):
z_ht_before += z_ht_after
z_ht_after = 0
elif is_half_turn(m_ht):
z_ht_after -= z_ht_before
z_ht_before = 0
# Generate operations
rotation_list = [
(ops.Pauli.Z, z_ht_before),
(m_pauli, m_ht),
(ops.Pauli.Z, z_ht_after)]
is_clifford_list = [is_clifford_rotation(ht)
for pauli, ht in rotation_list]
op_list = [rotation_to_clifford_op(pauli, qubit, ht) if is_clifford
else rotation_to_non_clifford_op(pauli, qubit, ht)
for is_clifford, (pauli, ht) in
zip(is_clifford_list, rotation_list)]
# Merge adjacent Clifford gates
for i in reversed(range(len(op_list) - 1)):
if is_clifford_list[i] and is_clifford_list[i+1]:
op_list[i] = op_list[i].gate.merged_with(op_list[i+1].gate
)(qubit)
is_clifford_list.pop(i+1)
op_list.pop(i+1)
# Yield non-identity ops
for is_clifford, op in zip(is_clifford_list, op_list):
if is_clifford and op.gate == ops.CliffordGate.I:
continue
yield op
def generate_ops():
conv_cz = ops.PauliInteractionGate(ops.Pauli.Z, False,
ops.Pauli.Z, False)
matrices = {qubit: np.eye(2) for qubit in qubits}
def clear_matrices(qubits):
for qubit in qubits:
yield single_qubit_matrix_to_ops(matrices[qubit], qubit)
matrices[qubit] = np.eye(2)
for op in xmon_circuit.all_operations():
# Assumes all Xmon operations are GateOperation
gate = op.gate
if isinstance(gate, google.XmonMeasurementGate):
yield clear_matrices(op.qubits)
yield ops.MeasurementGate(gate.key, gate.invert_mask
)(*op.qubits)
elif len(op.qubits) == 1:
# Collect all one qubit rotations
# Assumes all Xmon gates implement KnownMatrix
qubit, = op.qubits
matrices[qubit] = op.matrix().dot(matrices[qubit])
elif isinstance(gate, google.Exp11Gate):
yield clear_matrices(op.qubits)
if gate.half_turns != 1:
# coverage: ignore
raise ValueError('Unexpected partial CZ: {}'.format(op))
yield conv_cz(*op.qubits)
else:
# coverage: ignore
raise TypeError('Unknown Xmon operation: {}'.format(op))
yield clear_matrices(qubits)
return circuits.Circuit.from_ops(
generate_ops(),
strategy=circuits.InsertStrategy.EARLIEST)
def converted_gate_set(circuit: circuits.Circuit,
atol: float = 1e-7) -> circuits.Circuit:
"""Returns a new, equivalent circuit using the gate set {CliffordGate,
PauliInteractionGate, PauliStringPhasor}.
The circuit structure may differ because it is optimized during conversion.
"""
xmon_circuit = google.optimized_for_xmon(circuit, allow_partial_czs=False)
qubits = circuit.all_qubits()
tol = linalg.Tolerance(atol=atol)
def is_clifford_rotation(half_turns):
return tol.all_near_zero_mod(half_turns, 0.5)
def to_quarter_turns(half_turns):
return round(2 * half_turns) % 4
def is_quarter_turn(half_turns):
return (is_clifford_rotation(half_turns)
and to_quarter_turns(half_turns) % 2 == 1)
def is_half_turn(half_turns):
return (is_clifford_rotation(half_turns)
and to_quarter_turns(half_turns) == 2)
def is_no_turn(half_turns):
return (is_clifford_rotation(half_turns)
and to_quarter_turns(half_turns) == 0)
def rotation_to_clifford_op(pauli, qubit, half_turns):
quarter_turns = to_quarter_turns(half_turns)
if quarter_turns == 0:
return ops.CliffordGate.I(qubit)
elif quarter_turns == 2:
return ops.CliffordGate.from_pauli(pauli)(qubit)
else:
gate = ops.CliffordGate.from_pauli(pauli, True)(qubit)
if quarter_turns == 3:
gate = gate.inverse()
return gate
def rotation_to_non_clifford_op(pauli, qubit, half_turns):
return PauliStringPhasor(ops.PauliString.from_single(qubit, pauli),
half_turns=half_turns)
def single_qubit_matrix_to_ops(mat, qubit):
# Decompose matrix
z_rad_before, y_rad, z_rad_after = (
linalg.deconstruct_single_qubit_matrix_into_angles(mat))
z_ht_before = z_rad_before / np.pi - 0.5
m_ht = y_rad / np.pi
m_pauli = ops.Pauli.X
z_ht_after = z_rad_after / np.pi + 0.5
# Clean up angles
if is_clifford_rotation(z_ht_before):
if is_quarter_turn(z_ht_before) or is_quarter_turn(z_ht_after):
z_ht_before += 0.5
z_ht_after -= 0.5
m_pauli = ops.Pauli.Y
if is_half_turn(z_ht_before) or is_half_turn(z_ht_after):
z_ht_before -= 1
z_ht_after += 1
m_ht = -m_ht
if is_no_turn(m_ht):
z_ht_before += z_ht_after
z_ht_after = 0
elif is_half_turn(m_ht):
z_ht_after -= z_ht_before
z_ht_before = 0
# Generate operations
rotation_list = [(ops.Pauli.Z, z_ht_before), (m_pauli, m_ht),
(ops.Pauli.Z, z_ht_after)]
is_clifford_list = [
is_clifford_rotation(ht) for pauli, ht in rotation_list
]
op_list = [
rotation_to_clifford_op(pauli, qubit, ht)
if is_clifford else rotation_to_non_clifford_op(pauli, qubit, ht)
for is_clifford, (pauli,
ht) in zip(is_clifford_list, rotation_list)
]
# Merge adjacent Clifford gates
for i in reversed(range(len(op_list) - 1)):
if is_clifford_list[i] and is_clifford_list[i + 1]:
op_list[i] = op_list[i].gate.merged_with(
op_list[i + 1].gate)(qubit)
is_clifford_list.pop(i + 1)
op_list.pop(i + 1)
# Yield non-identity ops
for is_clifford, op in zip(is_clifford_list, op_list):
if is_clifford and op.gate == ops.CliffordGate.I:
continue
yield op
def generate_ops():
conv_cz = ops.PauliInteractionGate(ops.Pauli.Z, False, ops.Pauli.Z,
False)
matrices = {qubit: np.eye(2) for qubit in qubits}
def clear_matrices(qubits):
for qubit in qubits:
yield single_qubit_matrix_to_ops(matrices[qubit], qubit)
matrices[qubit] = np.eye(2)
for op in xmon_circuit.all_operations():
# Assumes all Xmon operations are GateOperation
gate = op.gate
if isinstance(gate, google.XmonMeasurementGate):
yield clear_matrices(op.qubits)
yield ops.MeasurementGate(gate.key,
gate.invert_mask)(*op.qubits)
elif len(op.qubits) == 1:
# Collect all one qubit rotations
# Assumes all Xmon gates implement KnownMatrix
qubit, = op.qubits
matrices[qubit] = op.matrix().dot(matrices[qubit])
elif isinstance(gate, google.Exp11Gate):
yield clear_matrices(op.qubits)
if gate.half_turns != 1:
# coverage: ignore
raise ValueError('Unexpected partial CZ: {}'.format(op))
yield conv_cz(*op.qubits)
else:
# coverage: ignore
raise TypeError('Unknown Xmon operation: {}'.format(op))
yield clear_matrices(qubits)
return circuits.Circuit.from_ops(generate_ops(),
strategy=circuits.InsertStrategy.EARLIEST)
