qiskit/test/python/transpiler/test_elide_permutations.py

492 lines
15 KiB
Python

# This code is part of Qiskit.
#
# (C) Copyright IBM 2023
#
# 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 ElidePermutations pass"""
import unittest
from qiskit.circuit.quantumcircuit import QuantumCircuit
from qiskit.circuit.library.generalized_gates import PermutationGate
from qiskit.transpiler.passes.optimization.elide_permutations import ElidePermutations
from qiskit.transpiler.passes.routing import StarPreRouting
from qiskit.circuit.controlflow import IfElseOp
from qiskit.quantum_info import Operator
from qiskit.transpiler.coupling import CouplingMap
from qiskit.transpiler.preset_passmanagers import generate_preset_pass_manager
from test import QiskitTestCase # pylint: disable=wrong-import-order
class TestElidePermutations(QiskitTestCase):
"""Test elide permutations logical optimization pass."""
def setUp(self):
super().setUp()
self.swap_pass = ElidePermutations()
def test_no_swap(self):
"""Test no swap means no transform."""
qc = QuantumCircuit(2)
qc.h(0)
qc.cx(0, 1)
qc.measure_all()
res = self.swap_pass(qc)
self.assertEqual(res, qc)
def test_swap_in_middle(self):
"""Test swap in middle of bell is elided."""
qc = QuantumCircuit(3, 3)
qc.h(0)
qc.swap(0, 1)
qc.cx(1, 2)
qc.barrier(0, 1, 2)
qc.measure(0, 0)
qc.measure(1, 1)
qc.measure(2, 2)
expected = QuantumCircuit(3, 3)
expected.h(0)
expected.cx(0, 2)
expected.barrier(0, 1, 2)
expected.measure(1, 0)
expected.measure(0, 1)
expected.measure(2, 2)
res = self.swap_pass(qc)
self.assertEqual(res, expected)
def test_swap_at_beginning(self):
"""Test swap in beginning of bell is elided."""
qc = QuantumCircuit(3, 3)
qc.swap(0, 1)
qc.h(0)
qc.cx(1, 2)
qc.barrier(0, 1, 2)
qc.measure(0, 0)
qc.measure(1, 1)
qc.measure(2, 2)
expected = QuantumCircuit(3, 3)
expected.h(1)
expected.cx(0, 2)
expected.barrier(0, 1, 2)
expected.measure(1, 0)
expected.measure(0, 1)
expected.measure(2, 2)
res = self.swap_pass(qc)
self.assertEqual(res, expected)
def test_swap_at_end(self):
"""Test swap at the end of bell is elided."""
qc = QuantumCircuit(3, 3)
qc.h(0)
qc.cx(1, 2)
qc.barrier(0, 1, 2)
qc.measure(0, 0)
qc.measure(1, 1)
qc.measure(2, 2)
qc.swap(0, 1)
expected = QuantumCircuit(3, 3)
expected.h(0)
expected.cx(1, 2)
expected.barrier(0, 1, 2)
expected.measure(0, 0)
expected.measure(1, 1)
expected.measure(2, 2)
res = self.swap_pass(qc)
self.assertEqual(res, expected)
def test_multiple_swaps(self):
"""Test quantum circuit with multiple swaps."""
qc = QuantumCircuit(3)
qc.h(0)
qc.swap(0, 2)
qc.cx(0, 1)
qc.swap(1, 0)
qc.h(1)
expected = QuantumCircuit(3)
expected.h(0)
expected.cx(2, 1)
expected.h(2)
res = self.swap_pass(qc)
self.assertEqual(res, expected)
def test_swap_before_measure(self):
"""Test swap before measure is elided."""
qc = QuantumCircuit(3, 3)
qc.h(0)
qc.cx(1, 2)
qc.barrier(0, 1, 2)
qc.swap(0, 1)
qc.measure(0, 0)
qc.measure(1, 1)
qc.measure(2, 2)
expected = QuantumCircuit(3, 3)
expected.h(0)
expected.cx(1, 2)
expected.barrier(0, 1, 2)
expected.measure(1, 0)
expected.measure(0, 1)
expected.measure(2, 2)
res = self.swap_pass(qc)
self.assertEqual(res, expected)
def test_swap_if_else_block(self):
"""Test swap elision only happens outside control flow."""
qc = QuantumCircuit(3, 3)
qc.h(0)
with qc.if_test((0, 0)):
qc.swap(0, 1)
qc.cx(0, 1)
res = self.swap_pass(qc)
self.assertEqual(res, qc)
def test_swap_if_else_block_with_outside_swap(self):
"""Test swap elision only happens outside control flow."""
qc = QuantumCircuit(3, 3)
qc.h(0)
qc.swap(2, 0)
body = QuantumCircuit(2)
body.swap(0, 1)
if_else_op = IfElseOp((qc.clbits[0], 0), body)
qc.append(if_else_op, [0, 1])
qc.cx(0, 1)
expected = QuantumCircuit(3, 3)
expected.h(0)
expected.append(IfElseOp((expected.clbits[0], 0), body), [2, 1])
expected.cx(2, 1)
res = self.swap_pass(qc)
self.assertEqual(res, expected)
def test_swap_condition(self):
"""Test swap elision doesn't touch conditioned swap."""
qc = QuantumCircuit(3, 3)
qc.h(0)
with self.assertWarns(DeprecationWarning):
qc.swap(0, 1).c_if(qc.clbits[0], 0)
qc.cx(0, 1)
res = self.swap_pass(qc)
self.assertEqual(res, qc)
def test_permutation_in_middle(self):
"""Test permutation in middle of bell is elided."""
qc = QuantumCircuit(3, 3)
qc.h(0)
qc.append(PermutationGate([2, 1, 0]), [0, 1, 2])
qc.cx(1, 2)
qc.barrier(0, 1, 2)
qc.measure(0, 0)
qc.measure(1, 1)
qc.measure(2, 2)
expected = QuantumCircuit(3, 3)
expected.h(0)
expected.cx(1, 0)
expected.barrier(0, 1, 2)
expected.measure(2, 0)
expected.measure(1, 1)
expected.measure(0, 2)
res = self.swap_pass(qc)
self.assertEqual(res, expected)
def test_partial_permutation_in_middle(self):
"""Test with a permutation gate in the middle of a circuit,
with the permutation gate defined only on a subset of qubits.
"""
qc = QuantumCircuit(5)
qc.cx(0, 1)
qc.append(PermutationGate([1, 2, 0]), [0, 2, 4])
qc.cx(2, 3)
# The permutation corresponding to the permutation gate maps
# 2 -> 0, 4 -> 2, 0 -> 4, and 1 -> 1, 3 -> 3.
# Instead of the permutation gate, we can relabel the qubits
# 0 -> 2, 1 -> 1, 2 -> 4, 3 -> 3, 4 -> 2.
# Hence cx(2, 3) becomes cx(4, 3).
expected = QuantumCircuit(5)
expected.cx(0, 1)
expected.cx(4, 3)
pass_ = ElidePermutations()
res = pass_(qc)
# Make sure that the pass removes the permutation gate and remaps
# the following gate
self.assertEqual(res, expected)
# Make sure that the transpiled circuit *with* the final permutation
# is equivalent to the original circuit
perm = pass_.property_set["virtual_permutation_layout"].to_permutation(qc.qubits)
res.append(PermutationGate(perm), [0, 1, 2, 3, 4])
self.assertEqual(Operator(res), Operator(qc))
def test_permutation_at_beginning(self):
"""Test permutation in beginning of bell is elided."""
qc = QuantumCircuit(3, 3)
qc.append(PermutationGate([2, 1, 0]), [0, 1, 2])
qc.h(0)
qc.cx(1, 2)
qc.barrier(0, 1, 2)
qc.measure(0, 0)
qc.measure(1, 1)
qc.measure(2, 2)
expected = QuantumCircuit(3, 3)
expected.h(2)
expected.cx(1, 0)
expected.barrier(0, 1, 2)
expected.measure(2, 0)
expected.measure(1, 1)
expected.measure(0, 2)
res = self.swap_pass(qc)
self.assertEqual(res, expected)
def test_permutation_at_end(self):
"""Test permutation at end of bell is elided."""
qc = QuantumCircuit(3, 3)
qc.h(0)
qc.cx(1, 2)
qc.barrier(0, 1, 2)
qc.measure(0, 0)
qc.measure(1, 1)
qc.measure(2, 2)
qc.append(PermutationGate([2, 1, 0]), [0, 1, 2])
expected = QuantumCircuit(3, 3)
expected.h(0)
expected.cx(1, 2)
expected.barrier(0, 1, 2)
expected.measure(0, 0)
expected.measure(1, 1)
expected.measure(2, 2)
res = self.swap_pass(qc)
self.assertEqual(res, expected)
def test_swap_and_permutation(self):
"""Test a combination of swap and permutation gates."""
qc = QuantumCircuit(3, 3)
qc.append(PermutationGate([2, 1, 0]), [0, 1, 2])
qc.swap(0, 2)
qc.h(0)
qc.cx(1, 2)
qc.barrier(0, 1, 2)
qc.measure(0, 0)
qc.measure(1, 1)
qc.measure(2, 2)
expected = QuantumCircuit(3, 3)
expected.h(0)
expected.cx(1, 2)
expected.barrier(0, 1, 2)
expected.measure(0, 0)
expected.measure(1, 1)
expected.measure(2, 2)
res = self.swap_pass(qc)
self.assertEqual(res, expected)
def test_permutation_before_measure(self):
"""Test permutation before measure is elided."""
qc = QuantumCircuit(3, 3)
qc.h(0)
qc.cx(1, 2)
qc.barrier(0, 1, 2)
qc.append(PermutationGate([1, 2, 0]), [0, 1, 2])
qc.measure(0, 0)
qc.measure(1, 1)
qc.measure(2, 2)
expected = QuantumCircuit(3, 3)
expected.h(0)
expected.cx(1, 2)
expected.barrier(0, 1, 2)
expected.measure(1, 0)
expected.measure(2, 1)
expected.measure(0, 2)
res = self.swap_pass(qc)
self.assertEqual(res, expected)
class TestElidePermutationsInTranspileFlow(QiskitTestCase):
"""
Test elide permutations in the full transpile pipeline, especially that
"layout" and "final_layout" attributes are updated correctly
as to preserve unitary equivalence.
"""
def test_not_run_after_layout(self):
"""Test ElidePermutations doesn't do anything after layout."""
qc = QuantumCircuit(3)
qc.h(0)
qc.swap(0, 2)
qc.cx(0, 1)
qc.swap(1, 0)
qc.h(1)
spm = generate_preset_pass_manager(
optimization_level=1, initial_layout=list(range(2, -1, -1)), seed_transpiler=42
)
spm.layout += ElidePermutations()
res = spm.run(qc)
self.assertTrue(Operator.from_circuit(res).equiv(Operator(qc)))
self.assertIn("swap", res.count_ops())
self.assertTrue(res.layout.final_index_layout(), [0, 1, 2])
def test_unitary_equivalence(self):
"""Test unitary equivalence of the original and transpiled circuits."""
qc = QuantumCircuit(3)
qc.h(0)
qc.swap(0, 2)
qc.cx(0, 1)
qc.swap(1, 0)
qc.h(1)
with self.subTest("no coupling map"):
spm = generate_preset_pass_manager(optimization_level=3, seed_transpiler=42)
spm.init += ElidePermutations()
res = spm.run(qc)
self.assertTrue(Operator.from_circuit(res).equiv(Operator(qc)))
with self.subTest("with coupling map"):
spm = generate_preset_pass_manager(
optimization_level=3, seed_transpiler=42, coupling_map=CouplingMap.from_line(3)
)
spm.init += ElidePermutations()
res = spm.run(qc)
self.assertTrue(Operator.from_circuit(res).equiv(Operator(qc)))
def test_unitary_equivalence_routing_and_basis_translation(self):
"""Test on a larger example that includes routing and basis translation."""
qc = QuantumCircuit(5)
qc.h(0)
qc.swap(0, 2)
qc.cx(0, 1)
qc.swap(1, 0)
qc.cx(0, 1)
qc.cx(0, 2)
qc.cx(0, 3)
qc.cx(0, 4)
qc.append(PermutationGate([0, 2, 1]), [0, 1, 2])
qc.h(1)
with self.subTest("no coupling map"):
spm = generate_preset_pass_manager(optimization_level=3, seed_transpiler=42)
spm.init += ElidePermutations()
res = spm.run(qc)
self.assertTrue(Operator.from_circuit(res).equiv(Operator(qc)))
with self.subTest("with coupling map"):
spm = generate_preset_pass_manager(
optimization_level=3,
seed_transpiler=1234,
coupling_map=CouplingMap.from_line(5),
basis_gates=["u", "cz"],
)
spm.init += ElidePermutations()
res = spm.run(qc)
self.assertTrue(Operator.from_circuit(res).equiv(Operator(qc)))
with self.subTest("no coupling map but with initial layout"):
spm = generate_preset_pass_manager(
optimization_level=3,
seed_transpiler=1234,
initial_layout=[4, 2, 1, 3, 0],
basis_gates=["u", "cz"],
)
spm.init += ElidePermutations()
res = spm.run(qc)
self.assertTrue(Operator.from_circuit(res).equiv(Operator(qc)))
with self.subTest("coupling map and initial layout"):
spm = generate_preset_pass_manager(
optimization_level=3,
seed_transpiler=1234,
initial_layout=[4, 2, 1, 3, 0],
basis_gates=["u", "cz"],
coupling_map=CouplingMap.from_line(5),
)
spm.init += ElidePermutations()
res = spm.run(qc)
self.assertTrue(Operator.from_circuit(res).equiv(Operator(qc)))
with self.subTest("larger coupling map"):
spm = generate_preset_pass_manager(
optimization_level=3,
seed_transpiler=42,
coupling_map=CouplingMap.from_line(8),
)
spm.init += ElidePermutations()
res = spm.run(qc)
qc_with_ancillas = QuantumCircuit(8)
qc_with_ancillas.append(qc, [0, 1, 2, 3, 4])
self.assertTrue(Operator.from_circuit(res).equiv(Operator(qc_with_ancillas)))
with self.subTest("larger coupling map and initial layout"):
spm = generate_preset_pass_manager(
optimization_level=3,
seed_transpiler=42,
initial_layout=[4, 2, 7, 3, 6],
coupling_map=CouplingMap.from_line(8),
)
spm.init += ElidePermutations()
res = spm.run(qc)
qc_with_ancillas = QuantumCircuit(8)
qc_with_ancillas.append(qc, [0, 1, 2, 3, 4])
self.assertTrue(Operator.from_circuit(res).equiv(Operator(qc_with_ancillas)))
def test_unitary_equivalence_virtual_permutation_layout_composition(self):
"""Test on a larger example that includes routing and basis translation."""
qc = QuantumCircuit(5)
qc.h(0)
qc.swap(0, 2)
qc.cx(0, 1)
qc.swap(1, 0)
qc.cx(0, 1)
qc.cx(0, 2)
qc.cx(0, 3)
qc.cx(0, 4)
qc.append(PermutationGate([0, 2, 1]), [0, 1, 2])
qc.h(1)
with self.subTest("with coupling map"):
spm = generate_preset_pass_manager(
optimization_level=3,
seed_transpiler=1234,
coupling_map=CouplingMap.from_line(5),
basis_gates=["u", "cz"],
)
spm.init += ElidePermutations()
spm.init += StarPreRouting()
res = spm.run(qc)
self.assertTrue(Operator.from_circuit(res).equiv(Operator(qc)))
if __name__ == "__main__":
unittest.main()