qiskit/test/python/transpiler/test_remove_reset_in_zero_s...

110 lines
3.3 KiB
Python

# This code is part of Qiskit.
#
# (C) Copyright IBM 2017, 2019.
#
# This code is licensed under the Apache License, Version 2.0. You may
# obtain a copy of this license in the LICENSE.txt file in the root directory
# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.
#
# Any modifications or derivative works of this code must retain this
# copyright notice, and modified files need to carry a notice indicating
# that they have been altered from the originals.
"""Test RemoveResetInZeroState pass"""
import unittest
from qiskit import QuantumRegister, QuantumCircuit
from qiskit.passmanager.flow_controllers import DoWhileController
from qiskit.transpiler import PassManager
from qiskit.transpiler.passes import RemoveResetInZeroState, DAGFixedPoint
from qiskit.converters import circuit_to_dag
from test import QiskitTestCase # pylint: disable=wrong-import-order
class TestRemoveResetInZeroState(QiskitTestCase):
"""Test remove-reset-in-zero-state optimizations."""
def test_optimize_single_reset(self):
"""Remove a single reset
qr0:--|0>-- ==> qr0:----
"""
qr = QuantumRegister(1, "qr")
circuit = QuantumCircuit(qr)
circuit.reset(qr)
dag = circuit_to_dag(circuit)
expected = QuantumCircuit(qr)
pass_ = RemoveResetInZeroState()
after = pass_.run(dag)
self.assertEqual(circuit_to_dag(expected), after)
def test_dont_optimize_non_zero_state(self):
"""Do not remove reset if not in a zero state
qr0:--[H]--|0>-- ==> qr0:--[H]--|0>--
"""
qr = QuantumRegister(1, "qr")
circuit = QuantumCircuit(qr)
circuit.h(qr)
circuit.reset(qr)
dag = circuit_to_dag(circuit)
expected = QuantumCircuit(qr)
expected.h(qr)
expected.reset(qr)
pass_ = RemoveResetInZeroState()
after = pass_.run(dag)
self.assertEqual(circuit_to_dag(expected), after)
def test_optimize_single_reset_in_diff_qubits(self):
"""Remove a single reset in different qubits
qr0:--|0>-- qr0:----
==>
qr1:--|0>-- qr1:----
"""
qr = QuantumRegister(2, "qr")
circuit = QuantumCircuit(qr)
circuit.reset(qr)
dag = circuit_to_dag(circuit)
expected = QuantumCircuit(qr)
pass_ = RemoveResetInZeroState()
after = pass_.run(dag)
self.assertEqual(circuit_to_dag(expected), after)
class TestRemoveResetInZeroStateFixedPoint(QiskitTestCase):
"""Test RemoveResetInZeroState in a transpiler, using fixed point."""
def test_two_resets(self):
"""Remove two initial resets
qr0:--|0>-|0>-- ==> qr0:----
"""
qr = QuantumRegister(1, "qr")
circuit = QuantumCircuit(qr)
circuit.reset(qr[0])
circuit.reset(qr[0])
expected = QuantumCircuit(qr)
pass_manager = PassManager()
pass_manager.append(
DoWhileController(
[RemoveResetInZeroState(), DAGFixedPoint()],
do_while=lambda property_set: not property_set["dag_fixed_point"],
)
)
after = pass_manager.run(circuit)
self.assertEqual(expected, after)
if __name__ == "__main__":
unittest.main()