def _get_cccu_commands(
control_mapping: _ControlQubits, rsrc: ResourceAllocator,
max_num_qubits: int) -> Tuple[_ControlQubits, List[ICommand]]:
"""
Builds a circuit that computes the AND condition on the `control_mapping`
qubits (some possibly negated) into one qubit.
To acheive this, when the number of control bits is greater than `max_num_qubits`,
an `ancilla_allocator` may be used to allocate extra qubits.
The resulting computation consists of X gates (for negation) and CCX gates to
construct a computation tree. This tree has a logarithmic depth.
Returns a tuple consisting of a new control qubits dict and the computation commands.
"""
commands: List[ICommand] = []
for (qubit_id, is_positive) in control_mapping.items():
if is_positive == 0:
commands.append(GateCmd(X_GATE, qubit_id))
control_qubit_ids = list(control_mapping)
while len(control_qubit_ids) > max_num_qubits:
q1 = control_qubit_ids.pop(0)
q2 = control_qubit_ids.pop(0)
q3 = rsrc.allocate_qubit()
commands.append(GateCmd(X_GATE, q3, control_qubit_ids={q1, q2}))
control_qubit_ids.append(q3)
return {q: 1 for q in control_qubit_ids}, commands
def _test_one_qubit_command_3(self, cmd_class) -> None: min_unused_qubit_id = 2 cmd_1: ICommand = GateCmd(cmd_class, 0) cmd_2: ICommand = GateCmd(cmd_class, 1) commands: List[ICommand] = [cmd_1,cmd_2] actual: List[ICommand] = QuasarOpt().run(commands, min_unused_qubit_id) expected: List[ICommand] = [cmd_1, cmd_2] self.assertListEqual(actual, expected)
def _test_two_qubits_cu3_command_2(self) -> None:
min_unused_qubit_id = 2
cmd_1: ICommand = GateCmd(U3_GATE, 1, params=[2.2, 3.3, 4.4], control_qubit_ids={0})
cmd_2: ICommand = GateCmd(U3_GATE, 1, params=[2.2, 3.3, 4.4], control_qubit_ids={0})
commands: List[ICommand] = [cmd_1, cmd_2]
actual: List[ICommand] = QuasarOpt().run(commands, min_unused_qubit_id)
expected: List[ICommand] = [cmd_1, cmd_2]
self.assertListEqual(actual, expected)
def _test_one_qubit_u3_command_2(self) -> None: min_unused_qubit_id = 1 cmd_1: ICommand = GateCmd(U3_GATE, 0, params=[1.1, 2.2, 3.3]) cmd_2: ICommand = GateCmd(U3_GATE, 0, params=[1.1, 3.3, 2.2]) commands: List[ICommand] = [cmd_1, cmd_2] actual: List[ICommand] = QuasarOpt().run(commands, min_unused_qubit_id) expected: List[ICommand] = [cmd_1, cmd_2] self.assertListEqual(actual, expected)
def _test_three_qubits_command_5(self, cmd_class) -> None:
min_unused_qubit_id = 5
cmd_1: ICommand = GateCmd(cmd_class, 2, control_qubit_ids={0, 1})
cmd_2: ICommand = GateCmd(cmd_class, 0, control_qubit_ids={2, 1})
commands: List[ICommand] = [cmd_1, cmd_2]
actual: List[ICommand] = QuasarOpt().run(commands, min_unused_qubit_id)
expected: List[ICommand] = [cmd_1, cmd_2]
self.assertListEqual(actual, expected)
def _test_three_qubits_reset_command_3(self, cmd_class_1, cmd_class_2) -> None:
min_unused_qubit_id = 3
cmd_1: ICommand = GateCmd(cmd_class_1, 2, control_qubit_ids={0, 1})
cmd_2: ICommand = cmd_class_2(2)
cmd_3: ICommand = GateCmd(cmd_class_1, 2, control_qubit_ids={0, 1})
commands: List[ICommand] = [cmd_1, cmd_2, cmd_3]
actual: List[ICommand] = QuasarOpt().run(commands, min_unused_qubit_id)
expected: List[ICommand] = [cmd_1, cmd_2, cmd_3]
self.assertListEqual(actual, expected)
def _test_two_qubits_command_6(self, cmd_class) -> None:
min_unused_qubit_id = 4
cmd_1: ICommand = GateCmd(cmd_class, 1, control_qubit_ids={0})
cmd_2: ICommand = GateCmd(cmd_class, 3, control_qubit_ids={2})
cmd_3: ICommand = GateCmd(cmd_class, 1, control_qubit_ids={2})
commands: List[ICommand] = [cmd_1, cmd_2, cmd_3]
actual: List[ICommand] = QuasarOpt().run(commands, min_unused_qubit_id)
expected: List[ICommand] = [cmd_1, cmd_2, cmd_3]
self.assertListEqual(actual, expected)
def _test_one_qubit_commands_2(self, cmd_class_1, cmd_class_2) -> None: min_unused_qubit_id = 1 cmd_1: ICommand = GateCmd(cmd_class_1, 0) cmd_2: ICommand = GateCmd(cmd_class_2, 0) cmd_3: ICommand = GateCmd(cmd_class_2, 0) cmd_4: ICommand = GateCmd(cmd_class_1, 0) commands: List[ICommand] = [cmd_1, cmd_2, cmd_3, cmd_4] actual: List[ICommand] = QuasarOpt().run(commands, min_unused_qubit_id) expected: List[ICommand] = [] self.assertListEqual(actual, expected)
def _test_two_qubits_commands_3(self, cmd_class_1, cmd_class_2) -> None:
min_unused_qubit_id = 2
cmd_1: ICommand = GateCmd(cmd_class_1, 1, control_qubit_ids={0})
cmd_2: ICommand = GateCmd(cmd_class_2, 0, control_qubit_ids={1})
cmd_3: ICommand = GateCmd(cmd_class_2, 1, control_qubit_ids={0})
cmd_4: ICommand = GateCmd(cmd_class_1, 0, control_qubit_ids={1})
commands: List[ICommand] = [cmd_1, cmd_2, cmd_3, cmd_4]
actual: List[ICommand] = QuasarOpt().run(commands, min_unused_qubit_id)
expected: List[ICommand] = [cmd_1, cmd_2, cmd_3, cmd_4]
self.assertListEqual(actual, expected)
def inverse_command(command: ICommand):
if not isinstance(command, GateCmd):
raise ValueError(f"Inverse of {type(command)} is impossible.")
inv_gate, inv_params = invert_gate(command._gate, command._params)
return GateCmd(inv_gate, command.get_target_qubit_id(),
command.get_control_qubit_ids(), inv_params)
def _get_on_gate_commands(self, node: GateNode) -> List[ICommand]:
if not self._control_mapping:
return [
GateCmd(node.gate,
node.get_target_qubit_id(),
params=node.params)
]
negate_negative_commands: List[ICommand] = []
for qubit_id, mask in self._control_mapping.items():
if mask == 0:
negate_negative_commands.append(GateCmd(X_GATE, qubit_id))
num_ancillas = 0
commands: List[ICommand]
control_commands: List[ICommand] = []
control_qubit_ids = list(self._control_mapping)
max_controls = 2 if node.gate == X_GATE else 1 # TODO(adsz): to be defined by gate / target architecture
while len(control_qubit_ids) > max_controls:
control_1 = control_qubit_ids.pop(0)
control_2 = control_qubit_ids.pop(0)
ancilla = self._rsrc.allocate_qubit()
num_ancillas += 1
control_qubit_ids.append(ancilla)
control_commands.append(
GateCmd(X_GATE,
ancilla,
control_qubit_ids={control_1, control_2}))
controlled_command = GateCmd(node.gate,
node.get_target_qubit_id(),
params=node.params,
control_qubit_ids=set(control_qubit_ids))
commands = (control_commands + [controlled_command] +
self._inversed(control_commands))
self._rsrc.free_qubits(num_ancillas)
return (negate_negative_commands + commands +
self._inversed(negate_negative_commands))
def _get_qubit_negation_commands(control_mapping) -> List[ICommand]:
""" This function makes sure that all control qubits
are in fact positively controlling. """
result: List[ICommand] = []
for qubit_id, mask in control_mapping.items():
if mask == 0:
result.append(GateCmd(X_GATE, qubit_id))
control_mapping[qubit_id] = 1
return result
def check_commutation(cmd1: GateCmd, cmd2: GateCmd) -> bool:
""" Returns True if two gates can be swapped with no change to the outcome. """
# TODO(adsz): In future, it might be also beneficial to check commutation
# that alters the gates (with similar gate complexity).
if cmd1 == cmd2:
return True
if not ((cmd1.get_control_qubit_ids() | {cmd1.get_target_qubit_id()}) &
(cmd2.get_control_qubit_ids() | {cmd2.get_target_qubit_id()})):
return True
if cmd1.gate == Z_GATE and cmd2.gate == Z_GATE:
return True
if cmd1.gate == X_GATE and cmd2.gate == X_GATE:
if cmd1.get_target_qubit_id() in cmd2.get_control_qubit_ids():
return False
elif cmd2.get_target_qubit_id() in cmd1.get_control_qubit_ids():
return False
else:
return True
# TODO(adsz): Two simplest rules as a starting point. Add more rules.
return False
def on_if_flip(self, if_flip: IfFlipNode) -> None:
qubits_counter = self._rsrc.get_min_unused_qubit_id()
cvis = CompileVisitor(self._rsrc)
if_flip.get_condition().accept(cvis)
cvis._commands.extend(
CompileVisitor._get_reduced_commands(2, cvis._control_mapping,
cvis._rsrc))
cvis._commands.extend(
CompileVisitor._get_qubit_negation_commands(cvis._control_mapping))
control_qubit_ids = list(cvis._control_mapping)
if_commands: List[ICommand] = cvis._commands
flip_command = GateCmd(Z_GATE,
control_qubit_ids[-1],
control_qubit_ids=set(control_qubit_ids[:-1]))
self._commands.extend(if_commands + [flip_command] +
self._inversed(if_commands))
num_ancillas = self._rsrc.get_min_unused_qubit_id() - qubits_counter
self._rsrc.free_qubits(num_ancillas)
