ROLLOUT 0 · Qiskit/qiskit-terra
qiskit__qiskit-terra-5833
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471 stotal time
15tool calls
15model calls
5,169tokens generated
137,895prompt tokens read
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System instructions 4,822 characters
You are a principal Python software engineer resolving a repository issue in `/workspace`. Your sole objective is to produce a minimal, root-cause source patch that passes every hidden fail-to-pass and pass-to-pass regression test on the first grading run. ## Critical Environment & Grader Rules 1. **Air-Gapped Sandbox & Available CLI Tools**: No network access. Never run `pip`, `uv`, `conda`, or `git fetch`. Note: `rg` (`ripgrep`) is NOT installed in the container — always use `grep -rn --include="*.py"` for fast exact searches so you never waste a tool call on `command not found`. 2. **Protected Grading Paths**: Before running official verification, the grading harness **strips and reverts all changes** to `tests/`, `test/`, `testing/`, `test_*.py`, `*_test.py`, `conftest.py`, `pyproject.toml`, `setup.cfg`, `pytest.ini`, and `tox.ini`. Every part of your fix MUST reside in non-test production source files. 3. **Untracked File Trap (`git add -N .`)**: `submit_patch` stages ALL untracked files inside `/workspace`! Never leave reproduction or scratch files inside `/workspace` — run reproductions inline via `python3 - <<'PY'` or inside `/tmp/repro.py` in a single `run_command`. 4. **Stdout Truncation Rule**: `run_command` truncates stdout after the first 5,000 characters from the TOP. Always run pytest quietly with short tracebacks: `pytest path/to/test_file.py -k pattern -q --tb=short --no-header` If a test file is large, redirect output to `/tmp/pytest.log` and inspect `tail -n 80 /tmp/pytest.log` so failure tracebacks at the bottom are never cut off. 5. **Strict Pacing Discipline**: `get_status` and `submit_patch` are free and do NOT count toward `max_tool_calls`. Target **16-22 counted tool calls total**, and **begin your first `edit_file` change no later than tool call 15**. Reserve at least 4 calls for verification, `git status --short && git diff`, and submission. ## Execution Protocol ### Phase 1 — Pinpoint Code & Tests Immediately (1-2 tool calls) - The user message already contains `Workspace Layout` — do NOT waste a turn running `ls` on top-level directories. - Run a single compound `run_command` with `grep -rn --include="*.py"` to locate: (a) the exact symbols, error strings, or functions from the problem description, (b) **all parallel or sibling implementations** (for example sync + async variants, `Client` + `AsyncClient`, serializer + deserializer, multiple backends/dialects, base + subclass methods, `__init__.py` / `__all__` exports), and (c) the closest existing unit test files under `tests/`. ### Phase 2 — Deep Read & Spec Anchor (2-5 tool calls) - Use `read_file` with generous `start_line` and `end_line` windows (180-300 lines per call so you read whole modules in fewer calls) on the target function/class, callers, type annotations, and neighboring tests. - Before editing, verify every explicit and implicit requirement from the issue: exact parameter names, defaults, boundary/domain edge cases, exception types/messages, `None` vs empty collection vs falsy (`0`, `False`, `""`) semantics, mutability/copying, and return types. ### Phase 3 — Reproduce Bug in One Call (1 tool call) - Run ONE concise command (`python3 - <<'PY' ... PY` or targeted `pytest ... -q --tb=short --no-header`) via `run_command` to observe the exact pre-fix failure. Do NOT spend multiple tool calls writing separate reproduction scripts. ### Phase 4 — Surgical Implementation Across All Parallel Paths (1-4 tool calls) - Begin editing by tool call 15! Use `edit_file` with 4-6 lines of exact surrounding context copied from `read_file`. - Update ALL parallel codepaths (sync/async, multiple classes/dialects, type hints) consistently so partial fixes do not fail sibling tests. - **2-Strike Edit Rule**: If `edit_file` fails twice on the same block due to whitespace or escaping, do not retry `edit_file` a third time — apply an atomic Python transformation via `run_command` and immediately verify `python3 -m py_compile path/to/file.py`. ### Phase 5 — Edge-Case Verification, Diff Hygiene & Clean Exit (2-4 tool calls) - Run a single compound `run_command` testing both your reproduction + boundary edge cases (`None`, empty input, leading/trailing delimiters, subdomain/prefix boundaries, subclass/async parity) AND the relevant existing `pytest` module(s) with `-q --tb=short --no-header`. - Run `git status --short && git diff` via `run_command`. Confirm: - ZERO untracked (`??`) files in `/workspace` (`rm -f` any untracked workspace files immediately), - ZERO modifications to `tests/` or protected config files (`git checkout -- tests/` if touched), - Minimal, clean diff with valid imports and indentation. - Call `submit_patch` once verification passes, then respond with a brief 2-sentence plain-text summary and make NO further tool calls.
Task prompt 10,333 characters
You are evaluating a software engineering task for repository Qiskit/qiskit-terra.
Problem Statement:
OptimizeSwapBeforeMeasure needs multiple invocations
The `OptimizeSwapBeforeMeasure` pass is supposed to commute quantum SWAP gates that immediately precede measurements, past the measurements, and instead convert them to classical swap (i.e.just retarget the measurement clbit).
However this should be generalized to work with any permutation that happens before the measurements, not just one swap layer. I made this work by invoking it many times for the example below, but really one invocation should be smart enough to remove all the swaps (that whole swap network should be modeled as a permutation).
```py
from qiskit import QuantumCircuit
from qiskit.transpiler.passes import OptimizeSwapBeforeMeasure, Depth, FixedPoint
from qiskit.transpiler import PassManager
circ = QuantumCircuit(8, 8)
circ.swap(3, 4)
circ.swap(6, 7)
circ.swap(0, 1)
circ.swap(6, 7)
circ.swap(4, 5)
circ.swap(0, 1)
circ.swap(5, 6)
circ.swap(3, 4)
circ.swap(1, 2)
circ.swap(6, 7)
circ.swap(4, 5)
circ.swap(2, 3)
circ.swap(0, 1)
circ.swap(5, 6)
circ.swap(1, 2)
circ.swap(6, 7)
circ.swap(4, 5)
circ.swap(2, 3)
circ.swap(3, 4)
circ.swap(3, 4)
circ.swap(5, 6)
circ.swap(1, 2)
circ.swap(4, 5)
circ.swap(2, 3)
circ.swap(5, 6)
circ.measure(range(8), range(8))
print(circ)
_depth_check = [Depth(), FixedPoint('depth')]
_opt = [OptimizeSwapBeforeMeasure()]
def _opt_control(property_set):
return not property_set['depth_fixed_point']
pm = PassManager()
pm.append(_depth_check + _opt, do_while=_opt_control) # should not need this do_while
print(pm.run(circ))
```
```
┌─┐
q_0: ─X──X─────X────┤M├─────────────────────────────────
│ │ │ └╥┘ ┌─┐
q_1: ─X──X──X──X──X──╫─────X────┤M├─────────────────────
│ │ ║ │ └╥┘ ┌─┐
q_2: ───────X──X──X──╫──X──X─────╫──X────┤M├────────────
│ ║ │ ║ │ └╥┘┌─┐
q_3: ─X─────X──X─────╫──X──X──X──╫──X─────╫─┤M├─────────
│ │ ║ │ │ ║ ║ └╥┘┌─┐
q_4: ─X──X──X──X─────╫──X──X──X──╫──X─────╫──╫─┤M├──────
│ │ ║ │ ║ │ ║ ║ └╥┘┌─┐
q_5: ────X──X──X──X──╫──X──X─────╫──X──X──╫──╫──╫─┤M├───
│ │ ║ │ ║ │ ║ ║ ║ └╥┘┌─┐
q_6: ─X──X──X──X──X──╫──X──X─────╫─────X──╫──╫──╫──╫─┤M├
│ │ │ ║ │ ┌─┐ ║ ║ ║ ║ ║ └╥┘
q_7: ─X──X─────X─────╫──X─┤M├────╫────────╫──╫──╫──╫──╫─
║ └╥┘ ║ ║ ║ ║ ║ ║
c: 8/════════════════╩═════╩═════╩════════╩══╩══╩══╩══╩═
0 7 1 2 3 4 5 6
┌─┐
q_0: ──────┤M├───────────────
┌─┐└╥┘
q_1: ───┤M├─╫────────────────
┌─┐└╥┘ ║
q_2: ┤M├─╫──╫────────────────
└╥┘ ║ ║ ┌─┐
q_3: ─╫──╫──╫────┤M├─────────
║ ║ ║ └╥┘ ┌─┐
q_4: ─╫──╫──╫─────╫───────┤M├
║ ║ ║ ┌─┐ ║ └╥┘
q_5: ─╫──╫──╫─┤M├─╫────────╫─
║ ║ ║ └╥┘ ║ ┌─┐ ║
q_6: ─╫──╫──╫──╫──╫─┤M├────╫─
║ ║ ║ ║ ║ └╥┘┌─┐ ║
q_7: ─╫──╫──╫──╫──╫──╫─┤M├─╫─
║ ║ ║ ║ ║ ║ └╥┘ ║
c: 8/═╩══╩══╩══╩══╩══╩══╩══╩═
0 1 2 3 4 5 6 7
```
## Task Budget (Session terminates when any budget is exhausted)
- Time allowance: 7.5 minutes
- Tool calls allowance: 30 calls
- Max loop iterations: 40 turns
## Execution Environment Rules
- Single command timeout: 90 seconds (commands exceeding this fail without ending the session)
- Command output limit: 5000 characters
- File view limit: 150 lines per read_file call
- File character limit: 10000 characters per read_file call
- Environment is offline (no network/PyPI access). All repository and test dependencies are ALREADY pre-installed. Do NOT attempt to run pip install or download packages.
## Instructions:
0. All source code is under `/workspace`. Do NOT search outside `/workspace` (e.g. `/usr/`, `/wheels/`, system site-packages). If imports fail, the issue is in the source code under `/workspace`, not in missing system packages.
1. Analyze the problem statement and any provided hints carefully to identify all requested script paths, CLI subcommands, or Python modules.
2. Inspect existing codebase conventions and test files before making edits.
3. Verify your implementation using targeted tests or inline assertions before submitting.
4. Call submit_patch only after your implementation is complete and verified.
5. As your final action, you must return a text-only response reporting your completion to terminate the session.
## Workspace Layout
The repository is located at `/workspace`. Here is the directory tree (up to 3 levels):
```
./CODE_OF_CONDUCT.md
./CONTRIBUTING.md
./LICENSE.txt
./MANIFEST.in
./Make.bat
./Makefile
./README.md
./azure-pipelines.yml
./constraints.txt
./docs
./examples
./postBuild
./pyproject.toml
./qiskit
./qiskit/VERSION.txt
./qiskit/__init__.py
./qiskit/algorithms
./qiskit/algorithms/__init__.py
./qiskit/algorithms/algorithm_result.py
./qiskit/algorithms/amplitude_amplifiers
./qiskit/algorithms/amplitude_estimators
./qiskit/algorithms/eigen_solvers
./qiskit/algorithms/exceptions.py
./qiskit/algorithms/factorizers
./qiskit/algorithms/minimum_eigen_solvers
./qiskit/algorithms/optimizers
./qiskit/algorithms/variational_algorithm.py
./qiskit/algorithms/variational_forms
./qiskit/assembler
./qiskit/assembler/__init__.py
./qiskit/assembler/assemble_circuits.py
./qiskit/assembler/assemble_schedules.py
./qiskit/assembler/disassemble.py
./qiskit/assembler/run_config.py
./qiskit/circuit
./qiskit/circuit/__init__.py
./qiskit/circuit/_utils.py
./qiskit/circuit/add_control.py
./qiskit/circuit/barrier.py
./qiskit/circuit/bit.py
./qiskit/circuit/classicalfunction
./qiskit/circuit/classicalregister.py
./qiskit/circuit/controlledgate.py
./qiskit/circuit/delay.py
./qiskit/circuit/duration.py
./qiskit/circuit/equivalence.py
./qiskit/circuit/equivalence_library.py
./qiskit/circuit/exceptions.py
./qiskit/circuit/gate.py
./qiskit/circuit/instruction.py
./qiskit/circuit/instructionset.py
./qiskit/circuit/library
./qiskit/circuit/measure.py
./qiskit/circuit/parameter.py
./qiskit/circuit/parameterexpression.py
./qiskit/circuit/parametertable.py
./qiskit/circuit/parametervector.py
./qiskit/circuit/quantumcircuit.py
./qiskit/circuit/quantumcircuitdata.py
./qiskit/circuit/quantumregister.py
./qiskit/circuit/random
./qiskit/circuit/register.py
./qiskit/circuit/reset.py
./qiskit/circuit/tools
./qiskit/compiler
./qiskit/compiler/__init__.py
./qiskit/compiler/assembler.py
./qiskit/compiler/scheduler.py
./qiskit/compiler/sequencer.py
./qiskit/compiler/transpiler.py
./qiskit/converters
./qiskit/converters/__init__.py
./qiskit/converters/ast_to_dag.py
./qiskit/converters/circuit_to_dag.py
./qiskit/converters/circuit_to_dagdependency.py
./qiskit/converters/circuit_to_gate.py
./qiskit/converters/circuit_to_instruction.py
./qiskit/converters/dag_to_circuit.py
./qiskit/converters/dag_to_dagdependency.py
./qiskit/converters/dagdependency_to_circuit.py
./qiskit/converters/dagdependency_to_dag.py
./qiskit/dagcircuit
./qiskit/dagcircuit/__init__.py
./qiskit/dagcircuit/dagcircuit.py
./qiskit/dagcircuit/dagdependency.py
./qiskit/dagcircuit/dagdepnode.py
./qiskit/dagcircuit/dagnode.py
./qiskit/dagcircuit/exceptions.py
./qiskit/exceptions.py
./qiskit/execute_function.py
./qiskit/extensions
./qiskit/extensions/__init__.py
./qiskit/extensions/exceptions.py
./qiskit/extensions/hamiltonian_gate.py
./qiskit/extensions/quantum_initializer
./qiskit/extensions/simulator
./qiskit/extensions/unitary.py
./qiskit/opflow
./qiskit/opflow/__init__.py
./qiskit/opflow/converters
./qiskit/opflow/evolutions
./qiskit/opflow/exceptions.py
./qiskit/opflow/expectations
./qiskit/opflow/gradients
./qiskit/opflow/list_ops
./qiskit/opflow/operator_base.py
./qiskit/opflow/operator_globals.py
./qiskit/opflow/primitive_ops
./qiskit/opflow/state_fns
./qiskit/providers
./qiskit/providers/__init__.py
./qiskit/providers/backend.py
./qiskit/providers/basebackend.py
./qiskit/providers/basejob.py
./qiskit/providers/baseprovider.py
./qiskit/providers/basicaer
./qiskit/providers/exceptions.py
./qiskit/providers/job.py
./qiskit/providers/jobstatus.py
./qiskit/providers/models
./qiskit/providers/options.py
./qiskit/providers/provider.py
./qiskit/providers/providerutils.py
./qiskit/pulse
./qiskit/pulse/__init__.py
./qiskit/pulse/builder.py
./qiskit/pulse/channels.py
./qiskit/pulse/configuration.py
./qiskit/pulse/exceptions.py
./qiskit/pulse/instruction_schedule_map.py
./qiskit/pulse/instructions
./qiskit/pulse/interfaces.py
./qiskit/pulse/library
./qiskit/pulse/macros.py
./qiskit/pulse/parser.py
./qiskit/pulse/reschedule.py
./qiskit/pulse/schedule.py
./qiskit/pulse/transforms.py
./qiskit/pulse/utils.py
./qiskit/qasm
./qiskit/qasm/__init__.py
./qiskit/qasm/exceptions.py
./qiskit/qasm/libs
./qiskit/qasm/node
./qiskit/qasm/pygments
./qiskit/qasm/qasm.py
./qiskit/qasm/qasmlexer.py
./qiskit/qasm/qasmparser.py
./qiskit/qobj
./qiskit/qobj/__init__.py
./qiskit/qobj/common.py
./qiskit/qobj/converters
./qiskit/qobj/pulse_qobj.py
./qiskit/qobj/qasm_qobj.py
./qiskit/qobj/utils.py
./qiskit/quantum_info
./qiskit/quantum_info/__init__.py
./qiskit/quantum_info/analysis
./qiskit/quantum_info/operators
./qiskit/quantum_info/random.py
./qiskit/quantum_info/states
./qiskit/quantum_info/synthesis
./qiskit/result
./qiskit/result/__init__.py
./qiskit/result/counts.py
./qiskit/result/exceptions.py
./qiskit/result/models.py
./qiskit/result/postprocess.py
./qiskit/result/result.py
./qiskit/result/utils.py
./qiskit/scheduler
./qiskit/scheduler/__init__.py
./qiskit/schemas
./qiskit/test
./qiskit/tools
./qiskit/transpiler
./qiskit/user_config.py
./qiskit/util.py
./qiskit/utils
./qiskit/validation
./qiskit/version.py
./qiskit/visualization
./releasenotes
./releasenotes/config.yaml
./releasenotes/notes
./requirements-dev.txt
./requirements.txt
./setup.py
./test
./test/__init__.py
./test/ipynb
./test/python
./test/randomized
./tools
./tools/find_optional_imports.py
./tools/report_ci_failure.py
./tools/subunit_to_junit.py
./tools/update_fake_backends.py
./tools/verify_headers.py
./tox.ini
```
Turn 1at 33 s180 tokens out5,925 prompt tokens
The user wants to fix a bug in `OptimizeSwapBeforeMeasure` pass. The problem is that the pass needs multiple invocations to remove all SWAP gates preceding measurements, but it should be able to do it in one invocation. I need to find the `OptimizeSwapBeforeMeasure` class and understand how it works. Based on the workspace layout, it should be in `qiskit/transpiler/passes`. Let's check `qiskit/transpiler` directory. Wait, the workspace layout shows `qiskit/transpiler`, but not its subdirectories. I'll use `grep` to find the definition.
TOOL CALL · run_command
{
"command": "grep -rn --include=\"*.py\" \"class OptimizeSwapBeforeMeasure\" qiskit/transpiler/"
}Result of run_command 187 characters
{
"status": "ok",
"stdout": "qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py:22:class OptimizeSwapBeforeMeasure(TransformationPass):\n",
"stderr": "",
"exit_code": 0
}Generated tokens 180 tokens · stopped: STOP
<|channel>thought
The user wants to fix a bug in `OptimizeSwapBeforeMeasure` pass.
The problem is that the pass needs multiple invocations to remove all SWAP gates preceding measurements, but it should be able to do it in one invocation.
I need to find the `OptimizeSwapBeforeMeasure` class and understand how it works.
Based on the workspace layout, it should be in `qiskit/transpiler/passes`. Let's check `qiskit/transpiler` directory.
Wait, the workspace layout shows `qiskit/transpiler`, but not its subdirectories. I'll use `grep` to find the definition.<channel|><|tool_call>call:run_command{command:<|"|>grep -rn --include="*.py" "class OptimizeSwapBeforeMeasure" qiskit/transpiler/<|"|>}<tool_call|><|tool_response>
Turn 2at 39 s78 tokens out6,179 prompt tokens
Okay, the file is `qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py`. Now I'll read the file to understand the implementation.
TOOL CALL · read_file
{
"filepath": "qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py"
}Result of read_file 3,047 characters
{
"status": "ok",
"filepath": "qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py",
"content": "# This code is part of Qiskit.\n#\n# (C) Copyright IBM 2017, 2019.\n#\n# This code is licensed under the Apache License, Version 2.0. You may\n# obtain a copy of this license in the LICENSE.txt file in the root directory\n# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.\n#\n# Any modifications or derivative works of this code must retain this\n# copyright notice, and modified files need to carry a notice indicating\n# that they have been altered from the originals.\n\n\n\"\"\"Remove the swaps followed by measurement (and adapt the measurement).\"\"\"\n\nfrom qiskit.circuit import Measure\nfrom qiskit.circuit.library.standard_gates import SwapGate\nfrom qiskit.transpiler.basepasses import TransformationPass\nfrom qiskit.dagcircuit import DAGCircuit\n\n\nclass OptimizeSwapBeforeMeasure(TransformationPass):\n \"\"\"Remove the swaps followed by measurement (and adapt the measurement).\n\n Transpiler pass to remove swaps in front of measurements by re-targeting\n the classical bit of the measure instruction.\n \"\"\"\n\n def run(self, dag):\n \"\"\"Run the OptimizeSwapBeforeMeasure pass on `dag`.\n\n Args:\n dag (DAGCircuit): the DAG to be optimized.\n\n Returns:\n DAGCircuit: the optimized DAG.\n \"\"\"\n swaps = dag.op_nodes(SwapGate)\n for swap in swaps:\n final_successor = []\n for successor in dag.successors(swap):\n final_successor.append(successor.type == 'out' or (successor.type == 'op' and\n successor.op.name == 'measure'))\n if all(final_successor):\n # the node swap needs to be removed and, if a measure follows, needs to be adapted\n swap_qargs = swap.qargs\n measure_layer = DAGCircuit()\n for qreg in dag.qregs.values():\n measure_layer.add_qreg(qreg)\n for creg in dag.cregs.values():\n measure_layer.add_creg(creg)\n for successor in list(dag.successors(swap)):\n if successor.type == 'op' and successor.op.name == 'measure':\n # replace measure node with a new one, where qargs is set with the \"other\"\n # swap qarg.\n dag.remove_op_node(successor)\n old_measure_qarg = successor.qargs[0]\n new_measure_qarg = swap_qargs[swap_qargs.index(old_measure_qarg) - 1]\n measure_layer.apply_operation_back(Measure(), [new_measure_qarg],\n [successor.cargs[0]])\n dag.compose(measure_layer)\n dag.remove_op_node(swap)\n return dag",
"start_line": 1,
"end_line": 63,
"total_lines": 63,
"is_truncated": false
}Generated tokens 78 tokens · stopped: STOP
Okay, the file is `qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py`.
Now I'll read the file to understand the implementation.
<channel|><|tool_call>call:read_file{filepath:<|"|>qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py<|"|>}<tool_call|><|tool_response>
Turn 3at 117 s1,169 tokens out7,068 prompt tokens
The current implementation of `run` does the following:
1. It finds all `SwapGate` op nodes.
2. For each swap, it checks if all its successors are either 'out' nodes or 'measure' nodes.
3. If so, it removes the swap and adapts the measurement if it exists.
The problem is that it only removes the "last" layer of swaps (those immediately preceding measurements). If there are multiple layers of swaps, it only removes one layer per invocation.
To generalize this, it should handle any number of swaps before measurements.
Essentially, if a qubit ends up being measured, we want to track the permutation resulting from any swaps that happen between the last non-swap/non-measure gate and the measurement.
Wait, the problem description says: "commute quantum SWAP gates that immediately precede measurements, past the measurements, and instead convert them to classical swap (i.e. just retarget the measurement clbit)".
Actually, if we have a sequence of swaps and then a measurement, the measurement will occur on whatever qubit ended up at that position.
Let's re-read the code carefully.
```python
swaps = dag.op_nodes(SwapGate)
for swap in swaps:
final_successor = []
for successor in dag.successors(swap):
final_successor.append(successor.type == 'out' or (successor.type == 'op' and
successor.op.name == 'measure'))
if all(final_successor):
# ...
```
It iterates over `dag.op_nodes(SwapGate)`. If a swap is followed only by measurements or 'out', it's removed.
If we have `Swap(0, 1)`, `Swap(0, 1)`, `Measure(0)`, `Measure(1)`.
The second `Swap(0, 1)` is followed by `Measure(0)` and `Measure(1)`. It will be removed.
Then we are left with `Swap(0, 1)`, `Measure(0)`, `Measure(1)`.
The first `Swap(0, 1)` was NOT followed only by measurements when the loop started (it was followed by the second swap).
So it requires another pass.
To fix this, we can repeat this process until no more swaps can be removed, or we can find all swaps that can be commuted past measurements.
Wait, the safest way is probably to use a fixed-point approach internally, or better, identify all qubits that are eventually measured and look at the sequence of swaps preceding those measurements.
Actually, a simpler approach: keep removing swaps that satisfy the condition until no more can be removed.
But let's think if there's a more efficient way.
If we have a chain of swaps, it's a permutation.
If we can move all these swaps "past" the measurements, it means the measurements are effectively on swapped qubits.
Let's verify the bug with the provided example.
TOOL CALL · run_command
{
"command": "python3 - <<'PY'\nfrom qiskit import QuantumCircuit\nfrom qiskit.transpiler.passes import OptimizeSwapBeforeMeasure, Depth, FixedPoint\nfrom qiskit.transpiler import PassManager\n\ncirc = QuantumCircuit(8, 8)\ncirc.swap(3, 4)\ncirc.swap(6, 7)\ncirc.swap(0, 1)\ncirc.swap(6, 7)\ncirc.swap(4, 5)\ncirc.swap(0, 1)\ncirc.swap(5, 6)\ncirc.swap(3, 4)\ncirc.swap(1, 2)\ncirc.swap(6, 7)\ncirc.swap(4, 5)\ncirc.swap(2, 3)\ncirc.swap(0, 1)\ncirc.swap(5, 6)\ncirc.swap(1, 2)\ncirc.swap(6, 7)\ncirc.swap(4, 5)\ncirc.swap(2, 3)\ncirc.swap(3, 4)\ncirc.swap(3, 4)\ncirc.swap(5, 6)\ncirc.swap(1, 2)\ncirc.swap(4, 5)\ncirc.swap(2, 3)\ncirc.swap(5, 6)\ncirc.measure(range(8), range(8))\n\n# Let's see the circuit before optimization\nprint(\"Before optimization:\")\nprint(circ)\n\n# One invocation of OptimizeSwapBeforeMeasure\nfrom qiskit.transpiler import PassManager\nfrom qiskit.transpiler.passes import OptimizeSwapBeforeMeasure\npm = PassManager([OptimizeSwapBeforeMeasure()])\noptimized_circ = pm.run(circ)\n\nprint(\"\\nAfter one invocation of OptimizeSwapBeforeMeasure:\")\nprint(optimized_circ)\n\n# Let's count how many swaps are left\n# We can count the number of 'swap' instructions in the circuit\nswap_count = 0\nfor instruction in optimized_circ.data:\n if instruction.operation.name == 'swap':\n swap_count += 1\nprint(f\"\\nNumber of swaps remaining: {swap_count}\")\nPY\n"
}Result of run_command 4,871 characters
{
"status": "error",
"error_type": "CommandError",
"error_message": "/workspace/qiskit/circuit/equivalence.py:18: DeprecationWarning: The retworkx package is deprecated and has been renamed to rustworkx. Rustworkx is a drop-in replacement and can be used by replacing `import retworkx` with import `rustworkx`. \n import retworkx as rx\n/workspace/qiskit/quantum_info/operators/operator.py:424: DeprecationWarning: __array__ implementation doesn't accept a copy keyword, so passing copy=False failed. __array__ must implement 'dtype' and 'copy' keyword arguments. To learn more, see the migration guide https://numpy.org/devdocs/numpy_2_0_migration_guide.html#adapting-to-changes-in-the-copy-keyword\n return Operator(np.array(instruction, dtype=complex))\n/workspace/qiskit/version.py:20: UserWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html. The pkg_resources package is slated for removal as early as 2025-11-30. Refrain from using this package or pin to Setuptools<81.\n import pkg_resources\nTraceback (most recent call last):\n File \"<stdin>\", line 1, in <module>\n File \"/workspace/qiskit/__init__.py\", line 53, in <module>\n from qiskit.execute_function import execute # noqa\n File \"/workspace/qiskit/execute_function.py\", line 24, in <module>\n from qiskit.compiler import transpile, assemble, schedule\n File \"/workspace/qiskit/compiler/__init__.py\", line 34, in <module>\n from .transpiler import transpile\n File \"/workspace/qiskit/compiler/transpiler.py\", line 35, in <module>\n from qiskit.transpiler.passes import ApplyLayout\n File \"/workspace/qiskit/transpiler/passes/__init__.py\", line 126, in <module>\n from .layout import SetLayout\n File \"/workspace/qiskit/transpiler/passes/layout/__init__.py\", line 19, in <module>\n from .sabre_layout import SabreLayout\n File \"/workspace/qiskit/transpiler/passes/layout/sabre_layout.py\", line 24, in <module>\n from qiskit.transpiler.passes.routing import SabreSwap\n File \"/workspace/qiskit/transpiler/passes/routing/__init__.py\", line 18, in <module>\n from .stochastic_swap import StochasticSwap\n File \"/workspace/qiskit/transpiler/passes/routing/stochastic_swap.py\", line 27, in <module>\n from .cython.stochastic_swap.utils import nlayout_from_layout\nModuleNotFoundError: No module named 'qiskit.transpiler.passes.routing.cython.stochastic_swap.utils'\n",
"details": {
"stdout": "",
"stderr": "/workspace/qiskit/circuit/equivalence.py:18: DeprecationWarning: The retworkx package is deprecated and has been renamed to rustworkx. Rustworkx is a drop-in replacement and can be used by replacing `import retworkx` with import `rustworkx`. \n import retworkx as rx\n/workspace/qiskit/quantum_info/operators/operator.py:424: DeprecationWarning: __array__ implementation doesn't accept a copy keyword, so passing copy=False failed. __array__ must implement 'dtype' and 'copy' keyword arguments. To learn more, see the migration guide https://numpy.org/devdocs/numpy_2_0_migration_guide.html#adapting-to-changes-in-the-copy-keyword\n return Operator(np.array(instruction, dtype=complex))\n/workspace/qiskit/version.py:20: UserWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html. The pkg_resources package is slated for removal as early as 2025-11-30. Refrain from using this package or pin to Setuptools<81.\n import pkg_resources\nTraceback (most recent call last):\n File \"<stdin>\", line 1, in <module>\n File \"/workspace/qiskit/__init__.py\", line 53, in <module>\n from qiskit.execute_function import execute # noqa\n File \"/workspace/qiskit/execute_function.py\", line 24, in <module>\n from qiskit.compiler import transpile, assemble, schedule\n File \"/workspace/qiskit/compiler/__init__.py\", line 34, in <module>\n from .transpiler import transpile\n File \"/workspace/qiskit/compiler/transpiler.py\", line 35, in <module>\n from qiskit.transpiler.passes import ApplyLayout\n File \"/workspace/qiskit/transpiler/passes/__init__.py\", line 126, in <module>\n from .layout import SetLayout\n File \"/workspace/qiskit/transpiler/passes/layout/__init__.py\", line 19, in <module>\n from .sabre_layout import SabreLayout\n File \"/workspace/qiskit/transpiler/passes/layout/sabre_layout.py\", line 24, in <module>\n from qiskit.transpiler.passes.routing import SabreSwap\n File \"/workspace/qiskit/transpiler/passes/routing/__init__.py\", line 18, in <module>\n from .stochastic_swap import StochasticSwap\n File \"/workspace/qiskit/transpiler/passes/routing/stochastic_swap.py\", line 27, in <module>\n from .cython.stochastic_swap.utils import nlayout_from_layout\nModuleNotFoundError: No module named 'qiskit.transpiler.passes.routing.cython.stochastic_swap.utils'\n",
"exit_code": 1
}
}Generated tokens 1,169 tokens · stopped: STOP
The current implementation of `run` does the following:
1. It finds all `SwapGate` op nodes.
2. For each swap, it checks if all its successors are either 'out' nodes or 'measure' nodes.
3. If so, it removes the swap and adapts the measurement if it exists.
The problem is that it only removes the "last" layer of swaps (those immediately preceding measurements). If there are multiple layers of swaps, it only removes one layer per invocation.
To generalize this, it should handle any number of swaps before measurements.
Essentially, if a qubit ends up being measured, we want to track the permutation resulting from any swaps that happen between the last non-swap/non-measure gate and the measurement.
Wait, the problem description says: "commute quantum SWAP gates that immediately precede measurements, past the measurements, and instead convert them to classical swap (i.e. just retarget the measurement clbit)".
Actually, if we have a sequence of swaps and then a measurement, the measurement will occur on whatever qubit ended up at that position.
Let's re-read the code carefully.
```python
swaps = dag.op_nodes(SwapGate)
for swap in swaps:
final_successor = []
for successor in dag.successors(swap):
final_successor.append(successor.type == 'out' or (successor.type == 'op' and
successor.op.name == 'measure'))
if all(final_successor):
# ...
```
It iterates over `dag.op_nodes(SwapGate)`. If a swap is followed only by measurements or 'out', it's removed.
If we have `Swap(0, 1)`, `Swap(0, 1)`, `Measure(0)`, `Measure(1)`.
The second `Swap(0, 1)` is followed by `Measure(0)` and `Measure(1)`. It will be removed.
Then we are left with `Swap(0, 1)`, `Measure(0)`, `Measure(1)`.
The first `Swap(0, 1)` was NOT followed only by measurements when the loop started (it was followed by the second swap).
So it requires another pass.
To fix this, we can repeat this process until no more swaps can be removed, or we can find all swaps that can be commuted past measurements.
Wait, the safest way is probably to use a fixed-point approach internally, or better, identify all qubits that are eventually measured and look at the sequence of swaps preceding those measurements.
Actually, a simpler approach: keep removing swaps that satisfy the condition until no more can be removed.
But let's think if there's a more efficient way.
If we have a chain of swaps, it's a permutation.
If we can move all these swaps "past" the measurements, it means the measurements are effectively on swapped qubits.
Let's verify the bug with the provided example.
<channel|><|tool_call>call:run_command{command:<|"|>python3 - <<'PY'
from qiskit import QuantumCircuit
from qiskit.transpiler.passes import OptimizeSwapBeforeMeasure, Depth, FixedPoint
from qiskit.transpiler import PassManager
circ = QuantumCircuit(8, 8)
circ.swap(3, 4)
circ.swap(6, 7)
circ.swap(0, 1)
circ.swap(6, 7)
circ.swap(4, 5)
circ.swap(0, 1)
circ.swap(5, 6)
circ.swap(3, 4)
circ.swap(1, 2)
circ.swap(6, 7)
circ.swap(4, 5)
circ.swap(2, 3)
circ.swap(0, 1)
circ.swap(5, 6)
circ.swap(1, 2)
circ.swap(6, 7)
circ.swap(4, 5)
circ.swap(2, 3)
circ.swap(3, 4)
circ.swap(3, 4)
circ.swap(5, 6)
circ.swap(1, 2)
circ.swap(4, 5)
circ.swap(2, 3)
circ.swap(5, 6)
circ.measure(range(8), range(8))
# Let's see the circuit before optimization
print("Before optimization:")
print(circ)
# One invocation of OptimizeSwapBeforeMeasure
from qiskit.transpiler import PassManager
from qiskit.transpiler.passes import OptimizeSwapBeforeMeasure
pm = PassManager([OptimizeSwapBeforeMeasure()])
optimized_circ = pm.run(circ)
print("\nAfter one invocation of OptimizeSwapBeforeMeasure:")
print(optimized_circ)
# Let's count how many swaps are left
# We can count the number of 'swap' instructions in the circuit
swap_count = 0
for instruction in optimized_circ.data:
if instruction.operation.name == 'swap':
swap_count += 1
print(f"\nNumber of swaps remaining: {swap_count}")
PY
<|"|>}<tool_call|><|tool_response>
Turn 4at 156 s658 tokens out9,780 prompt tokens
It seems I'm hitting a `ModuleNotFoundError: No module named 'qiskit.transpiler.passes.routing.cython.stochastic_swap.utils'`. This is strange, as the environment should be pre-installed with all dependencies. Maybe some modules are not compiled? Or maybe I should avoid importing `qiskit.transpiler.passes` at the top level if it pulls in too many things? The error occurs when `from qiskit.transpiler.passes import ApplyLayout` is called in `qiskit/compiler/transpiler.py`. I only need `OptimizeSwapBeforeMeasure`. Let's try to import only that pass specifically.
TOOL CALL · run_command
{
"command": "python3 - <<'PY'\nfrom qiskit.circuit import QuantumCircuit, Measure\nfrom qiskit.circuit.library.standard_gates import SwapGate\nfrom qiskit.transpiler.passes.optimization.optimize_swap_before_measure import OptimizeSwapBeforeMeasure\nfrom qiskit.transpiler.dagcircuit import DAGCircuit\nfrom qiskit.converters.circuit_to_dag import circuit_to_dag\nfrom qiskit.converters.dag_to_circuit import dag_to_circuit\n\ncirc = QuantumCircuit(8, 8)\ncirc.swap(3, 4)\ncirc.swap(6, 7)\ncirc.swap(0, 1)\ncirc.swap(6, 7)\ncirc.swap(4, 5)\ncirc.swap(0, 1)\ncirc.swap(5, 6)\ncirc.swap(3, 4)\ncirc.swap(1, 2)\ncirc.swap(6, 7)\ncirc.swap(4, 5)\ncirc.swap(2, 3)\ncirc.swap(0, 1)\ncirc.swap(5, 6)\ncirc.swap(1, 2)\ncirc.swap(6, 7)\ncirc.swap(4, 5)\ncirc.swap(2, 3)\ncirc.swap(3, 4)\ncirc.swap(3, 4)\ncirc.swap(5, 6)\ncirc.swap(1, 2)\ncirc.swap(4, 5)\ncirc.swap(2, 3)\ncirc.swap(5, 6)\ncirc.measure(range(8), range(8))\n\ndag = circuit_to_dag(circ)\npass_instance = OptimizeSwapBeforeMeasure()\noptimized_dag = pass_instance.run(dag)\noptimized_circ = dag_to_circuit(optimized_dag)\n\nswap_count = 0\nfor instruction in optimized_circ.data:\n if instruction.operation.name == 'swap':\n swap_count += 1\nprint(f\"Number of swaps remaining: {swap_count}\")\nPY\n"
}Result of run_command 4,871 characters
{
"status": "error",
"error_type": "CommandError",
"error_message": "/workspace/qiskit/circuit/equivalence.py:18: DeprecationWarning: The retworkx package is deprecated and has been renamed to rustworkx. Rustworkx is a drop-in replacement and can be used by replacing `import retworkx` with import `rustworkx`. \n import retworkx as rx\n/workspace/qiskit/quantum_info/operators/operator.py:424: DeprecationWarning: __array__ implementation doesn't accept a copy keyword, so passing copy=False failed. __array__ must implement 'dtype' and 'copy' keyword arguments. To learn more, see the migration guide https://numpy.org/devdocs/numpy_2_0_migration_guide.html#adapting-to-changes-in-the-copy-keyword\n return Operator(np.array(instruction, dtype=complex))\n/workspace/qiskit/version.py:20: UserWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html. The pkg_resources package is slated for removal as early as 2025-11-30. Refrain from using this package or pin to Setuptools<81.\n import pkg_resources\nTraceback (most recent call last):\n File \"<stdin>\", line 1, in <module>\n File \"/workspace/qiskit/__init__.py\", line 53, in <module>\n from qiskit.execute_function import execute # noqa\n File \"/workspace/qiskit/execute_function.py\", line 24, in <module>\n from qiskit.compiler import transpile, assemble, schedule\n File \"/workspace/qiskit/compiler/__init__.py\", line 34, in <module>\n from .transpiler import transpile\n File \"/workspace/qiskit/compiler/transpiler.py\", line 35, in <module>\n from qiskit.transpiler.passes import ApplyLayout\n File \"/workspace/qiskit/transpiler/passes/__init__.py\", line 126, in <module>\n from .layout import SetLayout\n File \"/workspace/qiskit/transpiler/passes/layout/__init__.py\", line 19, in <module>\n from .sabre_layout import SabreLayout\n File \"/workspace/qiskit/transpiler/passes/layout/sabre_layout.py\", line 24, in <module>\n from qiskit.transpiler.passes.routing import SabreSwap\n File \"/workspace/qiskit/transpiler/passes/routing/__init__.py\", line 18, in <module>\n from .stochastic_swap import StochasticSwap\n File \"/workspace/qiskit/transpiler/passes/routing/stochastic_swap.py\", line 27, in <module>\n from .cython.stochastic_swap.utils import nlayout_from_layout\nModuleNotFoundError: No module named 'qiskit.transpiler.passes.routing.cython.stochastic_swap.utils'\n",
"details": {
"stdout": "",
"stderr": "/workspace/qiskit/circuit/equivalence.py:18: DeprecationWarning: The retworkx package is deprecated and has been renamed to rustworkx. Rustworkx is a drop-in replacement and can be used by replacing `import retworkx` with import `rustworkx`. \n import retworkx as rx\n/workspace/qiskit/quantum_info/operators/operator.py:424: DeprecationWarning: __array__ implementation doesn't accept a copy keyword, so passing copy=False failed. __array__ must implement 'dtype' and 'copy' keyword arguments. To learn more, see the migration guide https://numpy.org/devdocs/numpy_2_0_migration_guide.html#adapting-to-changes-in-the-copy-keyword\n return Operator(np.array(instruction, dtype=complex))\n/workspace/qiskit/version.py:20: UserWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html. The pkg_resources package is slated for removal as early as 2025-11-30. Refrain from using this package or pin to Setuptools<81.\n import pkg_resources\nTraceback (most recent call last):\n File \"<stdin>\", line 1, in <module>\n File \"/workspace/qiskit/__init__.py\", line 53, in <module>\n from qiskit.execute_function import execute # noqa\n File \"/workspace/qiskit/execute_function.py\", line 24, in <module>\n from qiskit.compiler import transpile, assemble, schedule\n File \"/workspace/qiskit/compiler/__init__.py\", line 34, in <module>\n from .transpiler import transpile\n File \"/workspace/qiskit/compiler/transpiler.py\", line 35, in <module>\n from qiskit.transpiler.passes import ApplyLayout\n File \"/workspace/qiskit/transpiler/passes/__init__.py\", line 126, in <module>\n from .layout import SetLayout\n File \"/workspace/qiskit/transpiler/passes/layout/__init__.py\", line 19, in <module>\n from .sabre_layout import SabreLayout\n File \"/workspace/qiskit/transpiler/passes/layout/sabre_layout.py\", line 24, in <module>\n from qiskit.transpiler.passes.routing import SabreSwap\n File \"/workspace/qiskit/transpiler/passes/routing/__init__.py\", line 18, in <module>\n from .stochastic_swap import StochasticSwap\n File \"/workspace/qiskit/transpiler/passes/routing/stochastic_swap.py\", line 27, in <module>\n from .cython.stochastic_swap.utils import nlayout_from_layout\nModuleNotFoundError: No module named 'qiskit.transpiler.passes.routing.cython.stochastic_swap.utils'\n",
"exit_code": 1
}
}Generated tokens 658 tokens · stopped: STOP
It seems I'm hitting a `ModuleNotFoundError: No module named 'qiskit.transpiler.passes.routing.cython.stochastic_swap.utils'`. This is strange, as the environment should be pre-installed with all dependencies.
Maybe some modules are not compiled? Or maybe I should avoid importing `qiskit.transpiler.passes` at the top level if it pulls in too many things?
The error occurs when `from qiskit.transpiler.passes import ApplyLayout` is called in `qiskit/compiler/transpiler.py`.
I only need `OptimizeSwapBeforeMeasure`. Let's try to import only that pass specifically.
<channel|><|tool_call>call:run_command{command:<|"|>python3 - <<'PY'
from qiskit.circuit import QuantumCircuit, Measure
from qiskit.circuit.library.standard_gates import SwapGate
from qiskit.transpiler.passes.optimization.optimize_swap_before_measure import OptimizeSwapBeforeMeasure
from qiskit.transpiler.dagcircuit import DAGCircuit
from qiskit.converters.circuit_to_dag import circuit_to_dag
from qiskit.converters.dag_to_circuit import dag_to_circuit
circ = QuantumCircuit(8, 8)
circ.swap(3, 4)
circ.swap(6, 7)
circ.swap(0, 1)
circ.swap(6, 7)
circ.swap(4, 5)
circ.swap(0, 1)
circ.swap(5, 6)
circ.swap(3, 4)
circ.swap(1, 2)
circ.swap(6, 7)
circ.swap(4, 5)
circ.swap(2, 3)
circ.swap(0, 1)
circ.swap(5, 6)
circ.swap(1, 2)
circ.swap(6, 7)
circ.swap(4, 5)
circ.swap(2, 3)
circ.swap(3, 4)
circ.swap(3, 4)
circ.swap(5, 6)
circ.swap(1, 2)
circ.swap(4, 5)
circ.swap(2, 3)
circ.swap(5, 6)
circ.measure(range(8), range(8))
dag = circuit_to_dag(circ)
pass_instance = OptimizeSwapBeforeMeasure()
optimized_dag = pass_instance.run(dag)
optimized_circ = dag_to_circuit(optimized_dag)
swap_count = 0
for instruction in optimized_circ.data:
if instruction.operation.name == 'swap':
swap_count += 1
print(f"Number of swaps remaining: {swap_count}")
PY
<|"|>}<tool_call|><|tool_response>
Turn 5at 195 s744 tokens out11,981 prompt tokens
Wow, the `ModuleNotFoundError` is still happening because `from qiskit.circuit import QuantumCircuit` is triggering `import qiskit`, which then triggers `import qiskit.execute_function`, which then triggers `import qiskit.compiler`, etc. This is a problem for running my reproduction script. I need to avoid importing `qiskit` if it's broken in the environment, but `QuantumCircuit` and other things are part of it. Wait, is it possible that I just need to add the current directory to `PYTHONPATH` or something? No, it should be working. Wait, `qiskit/__init__.py` imports `qiskit.execute_function`. If I import from `qiskit.circuit` directly, it might avoid `qiskit/__init__.py`. Let me try to import from the specific files.
TOOL CALL · run_command
{
"command": "python3 - <<'PY'\nimport sys\nimport os\n\n# Try to avoid importing the top-level qiskit package if it's causing issues\n# and instead import from the specific modules.\nfrom qiskit.circuit.quantumcircuit import QuantumCircuit\nfrom qiskit.circuit.measure import Measure\nfrom qiskit.circuit.library.standard_gates import SwapGate\nfrom qiskit.transpiler.passes.optimization.optimize_swap_before_measure import OptimizeSwapBeforeMeasure\nfrom qiskit.dagcircuit.dagcircuit import DAGCircuit\nfrom qiskit.converters.circuit_to_dag import circuit_to_dag\nfrom qiskit.converters.dag_to_circuit import dag_to_circuit\n\ncirc = QuantumCircuit(8, 8)\ncirc.swap(3, 4)\ncirc.swap(6, 7)\ncirc.swap(0, 1)\ncirc.swap(6, 7)\ncirc.swap(4, 5)\ncirc.swap(0, 1)\ncirc.swap(5, 6)\ncirc.swap(3, 4)\ncirc.swap(1, 2)\ncirc.swap(6, 7)\ncirc.swap(4, 5)\ncirc.swap(2, 3)\ncirc.swap(0, 1)\ncirc.swap(5, 6)\ncirc.swap(1, 2)\ncirc.swap(6, 7)\ncirc.swap(4, 5)\ncirc.swap(2, 3)\ncirc.swap(3, 4)\ncirc.swap(3, 4)\ncirc.swap(5, 6)\ncirc.swap(1, 2)\ncirc.swap(4, 5)\ncirc.swap(2, 3)\ncirc.swap(5, 6)\ncirc.measure(range(8), range(8))\n\ndag = circuit_to_dag(circ)\npass_instance = OptimizeSwapBeforeMeasure()\noptimized_dag = pass_instance.run(dag)\noptimized_circ = dag_to_circuit(optimized_dag)\n\nswap_count = 0\nfor instruction in optimized_circ.data:\n if instruction.operation.name == 'swap':\n swap_count += 1\nprint(f\"Number of swaps remaining: {swap_count}\")\nPY\n"
}Result of run_command 4,871 characters
{
"status": "error",
"error_type": "CommandError",
"error_message": "/workspace/qiskit/circuit/equivalence.py:18: DeprecationWarning: The retworkx package is deprecated and has been renamed to rustworkx. Rustworkx is a drop-in replacement and can be used by replacing `import retworkx` with import `rustworkx`. \n import retworkx as rx\n/workspace/qiskit/quantum_info/operators/operator.py:424: DeprecationWarning: __array__ implementation doesn't accept a copy keyword, so passing copy=False failed. __array__ must implement 'dtype' and 'copy' keyword arguments. To learn more, see the migration guide https://numpy.org/devdocs/numpy_2_0_migration_guide.html#adapting-to-changes-in-the-copy-keyword\n return Operator(np.array(instruction, dtype=complex))\n/workspace/qiskit/version.py:20: UserWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html. The pkg_resources package is slated for removal as early as 2025-11-30. Refrain from using this package or pin to Setuptools<81.\n import pkg_resources\nTraceback (most recent call last):\n File \"<stdin>\", line 6, in <module>\n File \"/workspace/qiskit/__init__.py\", line 53, in <module>\n from qiskit.execute_function import execute # noqa\n File \"/workspace/qiskit/execute_function.py\", line 24, in <module>\n from qiskit.compiler import transpile, assemble, schedule\n File \"/workspace/qiskit/compiler/__init__.py\", line 34, in <module>\n from .transpiler import transpile\n File \"/workspace/qiskit/compiler/transpiler.py\", line 35, in <module>\n from qiskit.transpiler.passes import ApplyLayout\n File \"/workspace/qiskit/transpiler/passes/__init__.py\", line 126, in <module>\n from .layout import SetLayout\n File \"/workspace/qiskit/transpiler/passes/layout/__init__.py\", line 19, in <module>\n from .sabre_layout import SabreLayout\n File \"/workspace/qiskit/transpiler/passes/layout/sabre_layout.py\", line 24, in <module>\n from qiskit.transpiler.passes.routing import SabreSwap\n File \"/workspace/qiskit/transpiler/passes/routing/__init__.py\", line 18, in <module>\n from .stochastic_swap import StochasticSwap\n File \"/workspace/qiskit/transpiler/passes/routing/stochastic_swap.py\", line 27, in <module>\n from .cython.stochastic_swap.utils import nlayout_from_layout\nModuleNotFoundError: No module named 'qiskit.transpiler.passes.routing.cython.stochastic_swap.utils'\n",
"details": {
"stdout": "",
"stderr": "/workspace/qiskit/circuit/equivalence.py:18: DeprecationWarning: The retworkx package is deprecated and has been renamed to rustworkx. Rustworkx is a drop-in replacement and can be used by replacing `import retworkx` with import `rustworkx`. \n import retworkx as rx\n/workspace/qiskit/quantum_info/operators/operator.py:424: DeprecationWarning: __array__ implementation doesn't accept a copy keyword, so passing copy=False failed. __array__ must implement 'dtype' and 'copy' keyword arguments. To learn more, see the migration guide https://numpy.org/devdocs/numpy_2_0_migration_guide.html#adapting-to-changes-in-the-copy-keyword\n return Operator(np.array(instruction, dtype=complex))\n/workspace/qiskit/version.py:20: UserWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html. The pkg_resources package is slated for removal as early as 2025-11-30. Refrain from using this package or pin to Setuptools<81.\n import pkg_resources\nTraceback (most recent call last):\n File \"<stdin>\", line 6, in <module>\n File \"/workspace/qiskit/__init__.py\", line 53, in <module>\n from qiskit.execute_function import execute # noqa\n File \"/workspace/qiskit/execute_function.py\", line 24, in <module>\n from qiskit.compiler import transpile, assemble, schedule\n File \"/workspace/qiskit/compiler/__init__.py\", line 34, in <module>\n from .transpiler import transpile\n File \"/workspace/qiskit/compiler/transpiler.py\", line 35, in <module>\n from qiskit.transpiler.passes import ApplyLayout\n File \"/workspace/qiskit/transpiler/passes/__init__.py\", line 126, in <module>\n from .layout import SetLayout\n File \"/workspace/qiskit/transpiler/passes/layout/__init__.py\", line 19, in <module>\n from .sabre_layout import SabreLayout\n File \"/workspace/qiskit/transpiler/passes/layout/sabre_layout.py\", line 24, in <module>\n from qiskit.transpiler.passes.routing import SabreSwap\n File \"/workspace/qiskit/transpiler/passes/routing/__init__.py\", line 18, in <module>\n from .stochastic_swap import StochasticSwap\n File \"/workspace/qiskit/transpiler/passes/routing/stochastic_swap.py\", line 27, in <module>\n from .cython.stochastic_swap.utils import nlayout_from_layout\nModuleNotFoundError: No module named 'qiskit.transpiler.passes.routing.cython.stochastic_swap.utils'\n",
"exit_code": 1
}
}Generated tokens 744 tokens · stopped: STOP
Wow, the `ModuleNotFoundError` is still happening because `from qiskit.circuit import QuantumCircuit` is triggering `import qiskit`, which then triggers `import qiskit.execute_function`, which then triggers `import qiskit.compiler`, etc.
This is a problem for running my reproduction script. I need to avoid importing `qiskit` if it's broken in the environment, but `QuantumCircuit` and other things are part of it.
Wait, is it possible that I just need to add the current directory to `PYTHONPATH` or something? No, it should be working.
Wait, `qiskit/__init__.py` imports `qiskit.execute_function`.
If I import from `qiskit.circuit` directly, it might avoid `qiskit/__init__.py`.
Let me try to import from the specific files.<channel|><|tool_call>call:run_command{command:<|"|>python3 - <<'PY'
import sys
import os
# Try to avoid importing the top-level qiskit package if it's causing issues
# and instead import from the specific modules.
from qiskit.circuit.quantumcircuit import QuantumCircuit
from qiskit.circuit.measure import Measure
from qiskit.circuit.library.standard_gates import SwapGate
from qiskit.transpiler.passes.optimization.optimize_swap_before_measure import OptimizeSwapBeforeMeasure
from qiskit.dagcircuit.dagcircuit import DAGCircuit
from qiskit.converters.circuit_to_dag import circuit_to_dag
from qiskit.converters.dag_to_circuit import dag_to_circuit
circ = QuantumCircuit(8, 8)
circ.swap(3, 4)
circ.swap(6, 7)
circ.swap(0, 1)
circ.swap(6, 7)
circ.swap(4, 5)
circ.swap(0, 1)
circ.swap(5, 6)
circ.swap(3, 4)
circ.swap(1, 2)
circ.swap(6, 7)
circ.swap(4, 5)
circ.swap(2, 3)
circ.swap(0, 1)
circ.swap(5, 6)
circ.swap(1, 2)
circ.swap(6, 7)
circ.swap(4, 5)
circ.swap(2, 3)
circ.swap(3, 4)
circ.swap(3, 4)
circ.swap(5, 6)
circ.swap(1, 2)
circ.swap(4, 5)
circ.swap(2, 3)
circ.swap(5, 6)
circ.measure(range(8), range(8))
dag = circuit_to_dag(circ)
pass_instance = OptimizeSwapBeforeMeasure()
optimized_dag = pass_instance.run(dag)
optimized_circ = dag_to_circuit(optimized_dag)
swap_count = 0
for instruction in optimized_circ.data:
if instruction.operation.name == 'swap':
swap_count += 1
print(f"Number of swaps remaining: {swap_count}")
PY
<|"|>}<tool_call|><|tool_response>
Turn 6at 225 s416 tokens out14,269 prompt tokens
It seems that `from qiskit.circuit.quantumcircuit import QuantumCircuit` still triggers `import qiskit` somehow. Let's look at `qiskit/circuit/quantumcircuit.py` to see if it imports from `qiskit`.
Actually, the traceback shows that `File "/workspace/qiskit/__init__.py", line 53, in <module>` is being executed.
Wait, if I just want to verify the bug, and I can't run a full script due to environment issues, maybe I can just trust the problem description and fix it based on the code I read.
The code:
```python
swaps = dag.op_nodes(SwapGate)
for swap in swaps:
final_successor = []
for successor in dag.successors(swap):
final_successor.append(successor.type == 'out' or (successor.type == 'op' and
successor.op.name == 'measure'))
if all(final_successor):
# ... (remove swap and adapt measure)
```
The issue is clearly that it only iterates over the current swaps and removes those that are *currently* followed only by measurements or 'out'. It doesn't repeat the process to find swaps that *become* followed only by measurements after the first layer is removed.
To fix this, I can wrap the loop in a `while` loop that continues as long as at least one swap was removed.
However, modifying the DAG while iterating over its op nodes can be tricky. `dag.op_nodes(SwapGate)` might return a list that becomes stale.
Let's check how `dag.op_nodes()` is implemented.
It's probably in `qiskit/dagcircuit/dagcircuit.py`.
TOOL CALL · read_file
{
"filepath": "qiskit/dagcircuit/dagcircuit.py"
}Result of read_file 5,751 characters
{
"status": "ok",
"filepath": "qiskit/dagcircuit/dagcircuit.py",
"content": "# This code is part of Qiskit.\n#\n# (C) Copyright IBM 2017.\n#\n# This code is licensed under the Apache License, Version 2.0. You may\n# obtain a copy of this license in the LICENSE.txt file in the root directory\n# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.\n#\n# Any modifications or derivative works of this code must retain this\n# copyright notice, and modified files need to carry a notice indicating\n# that they have been altered from the originals.\n\n\"\"\"\nObject to represent a quantum circuit as a directed acyclic graph (DAG).\n\nThe nodes in the graph are either input/output nodes or operation nodes.\nThe edges correspond to qubits or bits in the circuit. A directed edge\nfrom node A to node B means that the (qu)bit passes from the output of A\nto the input of B. The object's methods allow circuits to be constructed,\ncomposed, and modified. Some natural properties like depth can be computed\ndirectly from the graph.\n\"\"\"\nfrom collections import OrderedDict, defaultdict\nimport copy\nimport itertools\nimport warnings\nimport math\n\nimport numpy as np\nimport retworkx as rx\n\nfrom qiskit.circuit.quantumregister import QuantumRegister, Qubit\nfrom qiskit.circuit.classicalregister import ClassicalRegister\nfrom qiskit.circuit.gate import Gate\nfrom qiskit.circuit.parameterexpression import ParameterExpression\nfrom qiskit.dagcircuit.exceptions import DAGCircuitError\nfrom qiskit.dagcircuit.dagnode import DAGNode\n\n\nclass DAGCircuit:\n \"\"\"\n Quantum circuit as a directed acyclic graph.\n\n There are 3 types of nodes in the graph: inputs, outputs, and operations.\n The nodes are connected by directed edges that correspond to qubits and\n bits.\n \"\"\"\n\n # pylint: disable=invalid-name\n\n def __init__(self):\n \"\"\"Create an empty circuit.\"\"\"\n\n # Circuit name. Generally, this corresponds to the name\n # of the QuantumCircuit from which the DAG was generated.\n self.name = None\n\n # Circuit metadata\n self.metadata = None\n\n # Set of wires (Register,idx) in the dag\n self._wires = set()\n\n # Map from wire (Register,idx) to input nodes of the graph\n self.input_map = OrderedDict()\n\n # Map from wire (Register,idx) to output nodes of the graph\n self.output_map = OrderedDict()\n\n # Directed multigraph whose nodes are inputs, outputs, or operations.\n # Operation nodes have equal in- and out-degrees and carry\n # additional data about the operation, including the argument order\n # and parameter values.\n # Input nodes have out-degree 1 and output nodes have in-degree 1.\n # Edges carry wire labels (reg,idx) and each operation has\n # corresponding in- and out-edges with the same wire labels.\n self._multi_graph = rx.PyDAG()\n\n # Map of qreg/creg name to Register object.\n self.qregs = OrderedDict()\n self.cregs = OrderedDict()\n\n # List of Qubit/Clbit wires that the DAG acts on.\n self.qubits = []\n self.clbits = []\n\n self._global_phase = 0\n self._calibrations = defaultdict(dict)\n\n self.duration = None\n self.unit = 'dt'\n\n def to_networkx(self):\n \"\"\"Returns a copy of the DAGCircuit in networkx format.\"\"\"\n try:\n import networkx as nx\n except ImportError:\n raise ImportError(\"Networkx is needed to use to_networkx(). It \"\n \"can be installed with 'pip install networkx'\")\n G = nx.MultiDiGraph()\n for node in self._multi_graph.nodes():\n G.add_node(node)\n for node_id in rx.topological_sort(self._multi_graph):\n for source_id, dest_id, edge in self._multi_graph.in_edges(node_id):\n G.add_edge(self._multi_graph[source_id],\n self._multi_graph[dest_id],\n **edge)\n return G\n\n @classmethod\n def from_networkx(cls, graph):\n \"\"\"Take a networkx MultiDigraph and create a new DAGCircuit.\n\n Args:\n graph (networkx.MultiDiGraph): The graph to create a DAGCircuit\n object from. The format of this MultiDiGraph format must be\n in the same format as returned by to_networkx.\n\n Returns:\n DAGCircuit: The dagcircuit object created from the networkx\n MultiDiGraph.\n Raises:\n ImportError: If networkx is not installed\n \"\"\"\n try:\n import networkx as nx\n except ImportError:\n raise ImportError(\"Networkx is needed to use from_networkx(). It \"\n \"can be installed with 'pip install networkx'\")\n dag = DAGCircuit()\n for node in nx.topological_sort(graph):\n if node.type == 'out':\n continue\n if node.type == 'in':\n dag._add_wire(node.wire)\n elif node.type == 'op':\n dag.apply_operation_back(node.op.copy(), node.qargs,\n node.cargs, node.condition)\n return dag\n\n @property\n def wires(self):\n \"\"\"Return a list of the wires in order.\"\"\"\n out_list = [bit for reg in self.qregs.values() for bit in reg]\n out_list += [bit for reg in self.cregs.values() for bit in reg]\n return out_list\n\n @property\n def node_counter(self):\n \"\"\"",
"start_line": 1,
"end_line": 150,
"total_lines": 1501,
"is_truncated": true
}Generated tokens 416 tokens · stopped: STOP
It seems that `from qiskit.circuit.quantumcircuit import QuantumCircuit` still triggers `import qiskit` somehow. Let's look at `qiskit/circuit/quantumcircuit.py` to see if it imports from `qiskit`.
Actually, the traceback shows that `File "/workspace/qiskit/__init__.py", line 53, in <module>` is being executed.
Wait, if I just want to verify the bug, and I can't run a full script due to environment issues, maybe I can just trust the problem description and fix it based on the code I read.
The code:
```python
swaps = dag.op_nodes(SwapGate)
for swap in swaps:
final_successor = []
for successor in dag.successors(swap):
final_successor.append(successor.type == 'out' or (successor.type == 'op' and
successor.op.name == 'measure'))
if all(final_successor):
# ... (remove swap and adapt measure)
```
The issue is clearly that it only iterates over the current swaps and removes those that are *currently* followed only by measurements or 'out'. It doesn't repeat the process to find swaps that *become* followed only by measurements after the first layer is removed.
To fix this, I can wrap the loop in a `while` loop that continues as long as at least one swap was removed.
However, modifying the DAG while iterating over its op nodes can be tricky. `dag.op_nodes(SwapGate)` might return a list that becomes stale.
Let's check how `dag.op_nodes()` is implemented.
It's probably in `qiskit/dagcircuit/dagcircuit.py`.<channel|><|tool_call>call:read_file{filepath:<|"|>qiskit/dagcircuit/dagcircuit.py<|"|>}<tool_call|><|tool_response>
Turn 7at 233 s93 tokens out16,242 prompt tokens
The `DAGCircuit` uses `retworkx.PyDAG`. `op_nodes` is likely a method that filters the nodes in the graph. Let's find the `op_nodes` implementation in `qiskit/dagcircuit/dagcircuit.py`.
TOOL CALL · run_command
{
"command": "grep -n \"def op_nodes\" qiskit/dagcircuit/dagcircuit.py"
}Result of run_command 124 characters
{
"status": "ok",
"stdout": "1090: def op_nodes(self, op=None, include_directives=True):\n",
"stderr": "",
"exit_code": 0
}Generated tokens 93 tokens · stopped: STOP
The `DAGCircuit` uses `retworkx.PyDAG`. `op_nodes` is likely a method that filters the nodes in the graph.
Let's find the `op_nodes` implementation in `qiskit/dagcircuit/dagcircuit.py`.
<channel|><|tool_call>call:run_command{command:<|"|>grep -n "def op_nodes" qiskit/dagcircuit/dagcircuit.py<|"|>}<tool_call|><|tool_response>
Turn 8at 289 s58 tokens out6,701 prompt tokens
Let's read `op_nodes` and surrounding lines.
TOOL CALL · read_file
{
"end_line": 1105,
"filepath": "qiskit/dagcircuit/dagcircuit.py",
"start_line": 1080
}Result of read_file 1,182 characters
{
"status": "ok",
"filepath": "qiskit/dagcircuit/dagcircuit.py",
"content": "\n elif isinstance(nodes, DAGNode):\n nodes = [nodes]\n for node in nodes:\n raw_nodes = self._multi_graph.out_edges(node._node_id)\n for source, dest, edge in raw_nodes:\n yield (self._multi_graph[source],\n self._multi_graph[dest],\n edge)\n\n def op_nodes(self, op=None, include_directives=True):\n \"\"\"Get the list of \"op\" nodes in the dag.\n\n Args:\n op (Type): :class:`qiskit.circuit.Instruction` subclass op nodes to\n return. If None, return all op nodes.\n include_directives (bool): include `barrier`, `snapshot` etc.\n\n Returns:\n list[DAGNode]: the list of node ids containing the given op.\n \"\"\"\n nodes = []\n for node in self._multi_graph.nodes():\n if node.type == \"op\":\n if not include_directives and node.name in ['snapshot', 'barrier']:\n continue",
"start_line": 1080,
"end_line": 1105,
"total_lines": 1501,
"is_truncated": false
}Generated tokens 58 tokens · stopped: STOP
Let's read `op_nodes` and surrounding lines.
<channel|><|tool_call>call:read_file{filepath:<|"|>qiskit/dagcircuit/dagcircuit.py<|"|>,end_line:1105,start_line:1080}<tool_call|><|tool_response>
Turn 9at 291 s57 tokens out7,102 prompt tokens
I need to see the rest of `op_nodes`.
TOOL CALL · read_file
{
"end_line": 1120,
"filepath": "qiskit/dagcircuit/dagcircuit.py",
"start_line": 1106
}Result of read_file 628 characters
{
"status": "ok",
"filepath": "qiskit/dagcircuit/dagcircuit.py",
"content": " if op is None or isinstance(node.op, op):\n nodes.append(node)\n return nodes\n\n def gate_nodes(self):\n \"\"\"Get the list of gate nodes in the dag.\n\n Returns:\n list[DAGNode]: the list of DAGNodes that represent gates.\n \"\"\"\n nodes = []\n for node in self.op_nodes():\n if isinstance(node.op, Gate):\n nodes.append(node)\n return nodes",
"start_line": 1106,
"end_line": 1120,
"total_lines": 1501,
"is_truncated": false
}Generated tokens 57 tokens · stopped: STOP
I need to see the rest of `op_nodes`.
<channel|><|tool_call>call:read_file{end_line:1120,filepath:<|"|>qiskit/dagcircuit/dagcircuit.py<|"|>,start_line:1106}<tool_call|><|tool_response>
Turn 10at 319 s339 tokens out7,362 prompt tokens
`op_nodes` returns a list.
Back to `OptimizeSwapBeforeMeasure.run`:
```python
def run(self, dag):
swaps = dag.op_nodes(SwapGate)
for swap in swaps:
final_successor = []
for successor in dag.successors(swap):
final_successor.append(successor.type == 'out' or (successor.type == 'op' and
successor.op.name == 'measure'))
if all(final_successor):
# ... remove swap
```
If we wrap this in a `while` loop, we need to make sure that we are updating the list of swaps.
```python
def run(self, dag):
while True:
swaps = dag.op_nodes(SwapGate)
removed_any = False
for swap in swaps:
# ...
if all(final_successor):
# remove swap
removed_any = True
if not removed_any:
break
return dag
```
Wait, the current implementation iterates over `swaps` and removes some of them. If we remove a swap, it might make another swap a candidate for removal.
Let's re-read the current `run` implementation.
TOOL CALL · read_file
{
"end_line": 45,
"filepath": "qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py",
"start_line": 20
}Result of read_file 1,204 characters
{
"status": "ok",
"filepath": "qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py",
"content": "\n\nclass OptimizeSwapBeforeMeasure(TransformationPass):\n \"\"\"Remove the swaps followed by measurement (and adapt the measurement).\n\n Transpiler pass to remove swaps in front of measurements by re-targeting\n the classical bit of the measure instruction.\n \"\"\"\n\n def run(self, dag):\n \"\"\"Run the OptimizeSwapBeforeMeasure pass on `dag`.\n\n Args:\n dag (DAGCircuit): the DAG to be optimized.\n\n Returns:\n DAGCircuit: the optimized DAG.\n \"\"\"\n swaps = dag.op_nodes(SwapGate)\n for swap in swaps:\n final_successor = []\n for successor in dag.successors(swap):\n final_successor.append(successor.type == 'out' or (successor.type == 'op' and\n successor.op.name == 'measure'))\n if all(final_successor):\n # the node swap needs to be removed and, if a measure follows, needs to be adapted",
"start_line": 20,
"end_line": 45,
"total_lines": 63,
"is_truncated": false
}Generated tokens 339 tokens · stopped: STOP
`op_nodes` returns a list.
Back to `OptimizeSwapBeforeMeasure.run`:
```python
def run(self, dag):
swaps = dag.op_nodes(SwapGate)
for swap in swaps:
final_successor = []
for successor in dag.successors(swap):
final_successor.append(successor.type == 'out' or (successor.type == 'op' and
successor.op.name == 'measure'))
if all(final_successor):
# ... remove swap
```
If we wrap this in a `while` loop, we need to make sure that we are updating the list of swaps.
```python
def run(self, dag):
while True:
swaps = dag.op_nodes(SwapGate)
removed_any = False
for swap in swaps:
# ...
if all(final_successor):
# remove swap
removed_any = True
if not removed_any:
break
return dag
```
Wait, the current implementation iterates over `swaps` and removes some of them. If we remove a swap, it might make another swap a candidate for removal.
Let's re-read the current `run` implementation.
<channel|><|tool_call>call:read_file{end_line:45,filepath:<|"|>qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py<|"|>,start_line:20}<tool_call|><|tool_response>
Turn 11at 325 s61 tokens out8,029 prompt tokens
And the rest of the `run` method:
TOOL CALL · read_file
{
"end_line": 63,
"filepath": "qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py",
"start_line": 46
}Result of read_file 1,252 characters
{
"status": "ok",
"filepath": "qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py",
"content": " swap_qargs = swap.qargs\n measure_layer = DAGCircuit()\n for qreg in dag.qregs.values():\n measure_layer.add_qreg(qreg)\n for creg in dag.cregs.values():\n measure_layer.add_creg(creg)\n for successor in list(dag.successors(swap)):\n if successor.type == 'op' and successor.op.name == 'measure':\n # replace measure node with a new one, where qargs is set with the \"other\"\n # swap qarg.\n dag.remove_op_node(successor)\n old_measure_qarg = successor.qargs[0]\n new_measure_qarg = swap_qargs[swap_qargs.index(old_measure_qarg) - 1]\n measure_layer.apply_operation_back(Measure(), [new_measure_qarg],\n [successor.cargs[0]])\n dag.compose(measure_layer)\n dag.remove_op_node(swap)\n return dag",
"start_line": 46,
"end_line": 63,
"total_lines": 63,
"is_truncated": false
}Generated tokens 61 tokens · stopped: STOP
And the rest of the `run` method:
<channel|><|tool_call>call:read_file{end_line:63,filepath:<|"|>qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py<|"|>,start_line:46}<tool_call|><|tool_response>
Turn 12at 336 s144 tokens out8,436 prompt tokens
Wait, this implementation is very interesting. It creates a `measure_layer` (which is a `DAGCircuit`) and then uses `dag.compose(measure_layer)`. `dag.compose(other_dag)` appends the `other_dag` to the end of the current `dag`. Wait, if it removes a `measure` node and then uses `dag.compose`, it's moving the measurement to the end of the DAG. Let's check how `dag.compose` is implemented.
TOOL CALL · run_command
{
"command": "grep -n \"def compose\" qiskit/dagcircuit/dagcircuit.py"
}Result of run_command 226 characters
{
"status": "ok",
"stdout": "561: def compose_back(self, input_circuit, edge_map=None):\n568: def compose(self, other, edge_map=None, qubits=None, clbits=None, front=False, inplace=True):\n",
"stderr": "",
"exit_code": 0
}Generated tokens 144 tokens · stopped: STOP
Wait, this implementation is very interesting. It creates a `measure_layer` (which is a `DAGCircuit`) and then uses `dag.compose(measure_layer)`.
`dag.compose(other_dag)` appends the `other_dag` to the end of the current `dag`.
Wait, if it removes a `measure` node and then uses `dag.compose`, it's moving the measurement to the end of the DAG.
Let's check how `dag.compose` is implemented.
<channel|><|tool_call>call:run_command{command:<|"|>grep -n "def compose" qiskit/dagcircuit/dagcircuit.py<|"|>}<tool_call|><|tool_response>
Turn 13at 339 s64 tokens out8,677 prompt tokens
Let's read `compose` in `qiskit/dagcircuit/dagcircuit.py`.
TOOL CALL · read_file
{
"end_line": 620,
"filepath": "qiskit/dagcircuit/dagcircuit.py",
"start_line": 568
}Result of read_file 2,888 characters
{
"status": "ok",
"filepath": "qiskit/dagcircuit/dagcircuit.py",
"content": " def compose(self, other, edge_map=None, qubits=None, clbits=None, front=False, inplace=True):\n \"\"\"Compose the ``other`` circuit onto the output of this circuit.\n\n A subset of input wires of ``other`` are mapped\n to a subset of output wires of this circuit.\n\n ``other`` can be narrower or of equal width to ``self``.\n\n Args:\n other (DAGCircuit): circuit to compose with self\n edge_map (dict): DEPRECATED - a {Bit: Bit} map from input wires of other\n to output wires of self (i.e. rhs->lhs).\n The key, value pairs can be either Qubit or Clbit mappings.\n qubits (list[Qubit|int]): qubits of self to compose onto.\n clbits (list[Clbit|int]): clbits of self to compose onto.\n front (bool): If True, front composition will be performed (not implemented yet)\n inplace (bool): If True, modify the object. Otherwise return composed circuit.\n\n Returns:\n DAGCircuit: the composed dag (returns None if inplace==True).\n\n Raises:\n DAGCircuitError: if ``other`` is wider or there are duplicate edge mappings.\n \"\"\"\n if front:\n raise DAGCircuitError(\"Front composition not supported yet.\")\n\n if len(other.qubits) > len(self.qubits) or \\\n len(other.clbits) > len(self.clbits):\n raise DAGCircuitError(\"Trying to compose with another DAGCircuit \"\n \"which has more 'in' edges.\")\n\n if edge_map is not None:\n warnings.warn(\"edge_map arg as a dictionary is deprecated. \"\n \"Use qubits and clbits args to specify a list of \"\n \"self edges to compose onto.\", DeprecationWarning,\n stacklevel=2)\n\n # number of qubits and clbits must match number in circuit or None\n identity_qubit_map = dict(zip(other.qubits, self.qubits))\n identity_clbit_map = dict(zip(other.clbits, self.clbits))\n if qubits is None:\n qubit_map = identity_qubit_map\n elif len(qubits) != len(other.qubits):\n raise DAGCircuitError(\"Number of items in qubits parameter does not\"\n \" match number of qubits in the circuit.\")\n else:\n qubit_map = {other.qubits[i]: (self.qubits[q] if isinstance(q, int) else q)\n for i, q in enumerate(qubits)}\n if clbits is None:\n clbit_map = identity_clbit_map\n elif len(clbits) != len(other.clbits):\n raise DAGCircuitError(\"Number of items in clbits parameter does not\"",
"start_line": 568,
"end_line": 620,
"total_lines": 1501,
"is_truncated": false
}Generated tokens 64 tokens · stopped: STOP
Let's read `compose` in `qiskit/dagcircuit/dagcircuit.py`.
<channel|><|tool_call>call:read_file{end_line:620,filepath:<|"|>qiskit/dagcircuit/dagcircuit.py<|"|>,start_line:568}<tool_call|><|tool_response>
Turn 14at 410 s1,052 tokens out9,518 prompt tokens
Wait, if `compose` is used to move the measurement to the end, it's actually a bit strange for an optimization pass that's supposed to just remove SWAPs. But if it's removing SWAPs before measurements, the measurement's position relative to other instructions might change.
Actually, if the SWAP is really "before measurement" and nothing else happens on those qubits, moving the measurement to the end of the DAG is okay.
The key is: the current `run` method iterates over the swaps *once*.
```python
swaps = dag.op_nodes(SwapGate)
for swap in swaps:
# ...
if all(final_successor):
# ... remove swap and adapt measure
```
If we have `SWAP1 -> SWAP2 -> MEASURE`, then the first time we run this:
1. `SWAP1` successors are `[SWAP2]`. `SWAP2` is not a measure or 'out'. So `SWAP1` is not removed.
2. `SWAP2` successors are `[MEASURE]`. `MEASURE` is a measure. So `SWAP2` is removed, and `MEASURE` is adapted.
After one pass, we have `SWAP1 -> MEASURE`.
The next time we run `OptimizeSwapBeforeMeasure`, `SWAP1` will be removed.
The goal is to do this in one pass.
The simplest fix is to wrap the loop in a `while` loop.
```python
def run(self, dag):
while True:
swaps = dag.op_nodes(SwapGate)
removed_any = False
for swap in swaps:
final_successor = []
for successor in dag.successors(swap):
final_successor.append(successor.type == 'out' or (successor.type == 'op' and
successor.op.name == 'measure'))
if all(final_successor):
# ... removal logic ...
removed_any = True
if not removed_any:
break
return dag
```
Wait, if I use `while True`, I should be careful about performance if there are many swaps. But typically, the number of swaps before measurement is small.
Let's check if there are any other potential issues.
In the original code:
```python
for successor in list(dag.successors(swap)):
if successor.type == 'op' and successor.op.name == 'measure':
# ...
dag.remove_op_node(successor)
# ...
measure_layer.apply_operation_back(Measure(), [new_measure_qarg], [successor.cargs[0]])
dag.compose(measure_layer)
dag.remove_op_node(swap)
```
If the `swap` was followed by a `measure`, it removes the `measure` node and adds a new one at the end of the DAG.
If I wrap it in a `while` loop:
Pass 1: `SWAP1 -> SWAP2 -> MEASURE`. `SWAP2` is removed, `MEASURE` is moved to the end.
Result: `SWAP1` -> ... -> `MEASURE`.
Now `SWAP1` is followed by `...`. If those `...` are just the DAG output nodes, then `SWAP1` can be removed.
Wait, if `SWAP2` was the only thing between `SWAP1` and `MEASURE`, then after `SWAP2` is removed, `SWAP1`'s successor becomes whatever was the successor of `SWAP2` (which was `MEASURE`, but `MEASURE` was moved to the end).
So after `SWAP2` is removed, `SWAP1` might be followed by an 'out' node or by the newly moved `MEASURE` (if it's now at the end).
Wait, `dag.compose(measure_layer)` adds the measure to the end of the DAG. So the successors of `SWAP1` will be the output nodes of the DAG, unless there were other things.
Actually, if `SWAP1`'s only successor was `SWAP2`, and `SWAP2` is removed, `SWAP1`'s successor now becomes what `SWAP2`'s successor was? No, that's not how DAGs work. When you remove a node, you usually have to reconnect its predecessors to its successors.
Let's check `dag.remove_op_node`.
TOOL CALL · run_command
{
"command": "grep -n \"def remove_op_node\" qiskit/dagcircuit/dagcircuit.py"
}Result of run_command 102 characters
{
"status": "ok",
"stdout": "1217: def remove_op_node(self, node):\n",
"stderr": "",
"exit_code": 0
}Generated tokens 1,052 tokens · stopped: STOP
Wait, if `compose` is used to move the measurement to the end, it's actually a bit strange for an optimization pass that's supposed to just remove SWAPs. But if it's removing SWAPs before measurements, the measurement's position relative to other instructions might change.
Actually, if the SWAP is really "before measurement" and nothing else happens on those qubits, moving the measurement to the end of the DAG is okay.
The key is: the current `run` method iterates over the swaps *once*.
```python
swaps = dag.op_nodes(SwapGate)
for swap in swaps:
# ...
if all(final_successor):
# ... remove swap and adapt measure
```
If we have `SWAP1 -> SWAP2 -> MEASURE`, then the first time we run this:
1. `SWAP1` successors are `[SWAP2]`. `SWAP2` is not a measure or 'out'. So `SWAP1` is not removed.
2. `SWAP2` successors are `[MEASURE]`. `MEASURE` is a measure. So `SWAP2` is removed, and `MEASURE` is adapted.
After one pass, we have `SWAP1 -> MEASURE`.
The next time we run `OptimizeSwapBeforeMeasure`, `SWAP1` will be removed.
The goal is to do this in one pass.
The simplest fix is to wrap the loop in a `while` loop.
```python
def run(self, dag):
while True:
swaps = dag.op_nodes(SwapGate)
removed_any = False
for swap in swaps:
final_successor = []
for successor in dag.successors(swap):
final_successor.append(successor.type == 'out' or (successor.type == 'op' and
successor.op.name == 'measure'))
if all(final_successor):
# ... removal logic ...
removed_any = True
if not removed_any:
break
return dag
```
Wait, if I use `while True`, I should be careful about performance if there are many swaps. But typically, the number of swaps before measurement is small.
Let's check if there are any other potential issues.
In the original code:
```python
for successor in list(dag.successors(swap)):
if successor.type == 'op' and successor.op.name == 'measure':
# ...
dag.remove_op_node(successor)
# ...
measure_layer.apply_operation_back(Measure(), [new_measure_qarg], [successor.cargs[0]])
dag.compose(measure_layer)
dag.remove_op_node(swap)
```
If the `swap` was followed by a `measure`, it removes the `measure` node and adds a new one at the end of the DAG.
If I wrap it in a `while` loop:
Pass 1: `SWAP1 -> SWAP2 -> MEASURE`. `SWAP2` is removed, `MEASURE` is moved to the end.
Result: `SWAP1` -> ... -> `MEASURE`.
Now `SWAP1` is followed by `...`. If those `...` are just the DAG output nodes, then `SWAP1` can be removed.
Wait, if `SWAP2` was the only thing between `SWAP1` and `MEASURE`, then after `SWAP2` is removed, `SWAP1`'s successor becomes whatever was the successor of `SWAP2` (which was `MEASURE`, but `MEASURE` was moved to the end).
So after `SWAP2` is removed, `SWAP1` might be followed by an 'out' node or by the newly moved `MEASURE` (if it's now at the end).
Wait, `dag.compose(measure_layer)` adds the measure to the end of the DAG. So the successors of `SWAP1` will be the output nodes of the DAG, unless there were other things.
Actually, if `SWAP1`'s only successor was `SWAP2`, and `SWAP2` is removed, `SWAP1`'s successor now becomes what `SWAP2`'s successor was? No, that's not how DAGs work. When you remove a node, you usually have to reconnect its predecessors to its successors.
Let's check `dag.remove_op_node`.
<channel|><|tool_call>call:run_command{command:<|"|>grep -n "def remove_op_node" qiskit/dagcircuit/dagcircuit.py<|"|>}<tool_call|><|tool_response>
Turn 15at 412 s56 tokens out10,626 prompt tokens
Let's read `remove_op_node`.
TOOL CALL · read_file
{
"end_line": 1240,
"filepath": "qiskit/dagcircuit/dagcircuit.py",
"start_line": 1217
}Result of read_file 1,153 characters
{
"status": "ok",
"filepath": "qiskit/dagcircuit/dagcircuit.py",
"content": " def remove_op_node(self, node):\n \"\"\"Remove an operation node n.\n\n Add edges from predecessors to successors.\n \"\"\"\n if node.type != 'op':\n raise DAGCircuitError('The method remove_op_node only works on op node types. An \"%s\" '\n 'node type was wrongly provided.' % node.type)\n\n self._multi_graph.remove_node_retain_edges(\n node._node_id, use_outgoing=False,\n condition=lambda edge1, edge2: edge1 == edge2)\n\n def remove_ancestors_of(self, node):\n \"\"\"Remove all of the ancestor operation nodes of node.\"\"\"\n anc = rx.ancestors(self._multi_graph, node)\n # TODO: probably better to do all at once using\n # multi_graph.remove_nodes_from; same for related functions ...\n\n for anc_node in anc:\n if anc_node.type == \"op\":\n self.remove_op_node(anc_node)\n\n def remove_descendants_of(self, node):",
"start_line": 1217,
"end_line": 1240,
"total_lines": 1501,
"is_truncated": false
}Generated tokens 56 tokens · stopped: STOP
Let's read `remove_op_node`.
<channel|><|tool_call>call:read_file{end_line:1240,filepath:<|"|>qiskit/dagcircuit/dagcircuit.py<|"|>,start_line:1217}<tool_call|><|tool_response>
Patch, tests and logs
Final code change Included
Test output Missing
Not saved for this rollout. Nothing has been inferred or reconstructed.
Test errors Missing
Not saved for this rollout. Nothing has been inferred or reconstructed.
Test report (JUnit) Missing
Not saved for this rollout. Nothing has been inferred or reconstructed.
Agent log Included
[ 0.0s] 📋 System Prompt: You are a principal Python software engineer resolving a repository issue in `/workspace`.
[ 0.0s] 🎯 Task Prompt: You are evaluating a software engineering task for repository Qiskit/qiskit-terra.
[ 14.9s] 💭 (542 chars) "The user wants to fix a bug in `OptimizeSwapBeforeMeasure` pass.
The problem is that the pass needs multiple invocations..."
[ 14.9s] 🔧 run_command grep -rn --include="*.py" "class OptimizeSwapBeforeMeasure" qiskit/transpiler/
[ 15.0s] → qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py:22:class
OptimizeSwapBeforeMeasure(TransformationP
[ 21.1s] 💭 (147 chars) "Okay, the file is `qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py`.
Now I'll read the file to und..."
[ 21.1s] 📖 read_file (qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py)
[ 21.2s] ✓ {'status': 'ok', 'filepath': 'qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py',
'content': '# This…
[ 99.2s] 💭 (2706 chars) "The current implementation of `run` does the following:
1. It finds all `SwapGate` op nodes.
2. For each swap, it checks..."
[ 99.2s] 🔧 run_command (54 lines) python3 - <<'PY'
[ 101.8s] → error (exit 0):
[ 137.9s] 💭 (568 chars) "It seems I'm hitting a `ModuleNotFoundError: No module named
'qiskit.transpiler.passes.routing.cython.stochastic_swap.ut..."
[ 137.9s] 🔧 run_command (47 lines) python3 - <<'PY'
[ 139.6s] → error (exit 0):
[ 176.7s] 💭 (731 chars) "Wow, the `ModuleNotFoundError` is still happening because `from qiskit.circuit import
QuantumCircuit` is triggering `imp..."
[ 176.7s] 🔧 run_command (53 lines) python3 - <<'PY'
[ 178.2s] → error (exit 0):
[ 206.9s] 💭 (1575 chars) "It seems that `from qiskit.circuit.quantumcircuit import QuantumCircuit` still triggers
`import qiskit` somehow. Let's l..."
[ 206.9s] 📖 read_file (qiskit/dagcircuit/dagcircuit.py)
[ 206.9s] ✓ {'status': 'ok', 'filepath': 'qiskit/dagcircuit/dagcircuit.py', 'content': '# This code is part of
Qiskit.\n#\n# (C) Cop…
[ 215.3s] 💭 (186 chars) "The `DAGCircuit` uses `retworkx.PyDAG`. `op_nodes` is likely a method that filters the nodes
in the graph.
Let's find t..."
[ 215.3s] 🔧 run_command grep -n "def op_nodes" qiskit/dagcircuit/dagcircuit.py
[ 215.3s] → 1090: def op_nodes(self, op=None, include_directives=True):
[ 270.6s] 💭 (44 chars) "Let's read `op_nodes` and surrounding lines."
[ 270.6s] 📖 read_file (qiskit/dagcircuit/dagcircuit.py)
[ 270.7s] ✓ {'status': 'ok', 'filepath': 'qiskit/dagcircuit/dagcircuit.py', 'content': '\n elif
isinstance(nodes, DAGNode):\n…
[ 273.3s] 💭 (37 chars) "I need to see the rest of `op_nodes`."
[ 273.3s] 📖 read_file (qiskit/dagcircuit/dagcircuit.py)
[ 273.3s] ✓ {'status': 'ok', 'filepath': 'qiskit/dagcircuit/dagcircuit.py', 'content': ' if op is
None or isinstance(…
[ 301.1s] 💭 (1197 chars) "`op_nodes` returns a list.
Back to `OptimizeSwapBeforeMeasure.run`:
```python
def run(self, dag):
swaps = ..."
[ 301.1s] 📖 read_file (qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py)
[ 301.1s] ✓ {'status': 'ok', 'filepath': 'qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py',
'content': '\n\ncl…
[ 307.1s] 💭 (33 chars) "And the rest of the `run` method:"
[ 307.1s] 📖 read_file (qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py)
[ 307.1s] ✓ {'status': 'ok', 'filepath': 'qiskit/transpiler/passes/optimization/optimize_swap_before_measure.py',
'content': ' …
[ 318.1s] 💭 (393 chars) "Wait, this implementation is very interesting. It creates a `measure_layer` (which is a
`DAGCircuit`) and then uses `dag..."
[ 318.1s] 🔧 run_command grep -n "def compose" qiskit/dagcircuit/dagcircuit.py
[ 318.1s] → 561: def compose_back(self, input_circuit, edge_map=None):
[ 320.6s] 💭 (58 chars) "Let's read `compose` in `qiskit/dagcircuit/dagcircuit.py`."
[ 320.6s] 📖 read_file (qiskit/dagcircuit/dagcircuit.py)
[ 320.6s] ✓ {'status': 'ok', 'filepath': 'qiskit/dagcircuit/dagcircuit.py', 'content': ' def compose(self, other,
edge_map=None, …
[ 391.5s] 💭 (3741 chars) "Wait, if `compose` is used to move the measurement to the end, it's actually a bit strange
for an optimization pass that..."
[ 391.5s] 🔧 run_command grep -n "def remove_op_node" qiskit/dagcircuit/dagcircuit.py
[ 391.6s] → 1217: def remove_op_node(self, node):
[ 393.8s] 💭 (28 chars) "Let's read `remove_op_node`."
[ 393.8s] 📖 read_file (qiskit/dagcircuit/dagcircuit.py)
[ 393.8s] ✓ {'status': 'ok', 'filepath': 'qiskit/dagcircuit/dagcircuit.py', 'content': ' def remove_op_node(self,
node):\n …
Native result row
{
"agent_error": "Agent exceeded session timeout (7.5 min)",
"duration_seconds": 470.77,
"error": "Empty agent patch",
"grade": {
"error": "Empty agent patch",
"resolved": false,
"strict_clean_patch": false,
"test_exit_code": -1
},
"instance_id": "qiskit__qiskit-terra-5833",
"pass_idx": 0,
"patch_chars": 0,
"phase1_seconds": 470.77,
"repo": "Qiskit/qiskit-terra",
"request_log_path": "/kaggle-root/working/r31/rollouts_X/requests/qiskit__qiskit-terra-5833__p0__r0.jsonl",
"resolved": false,
"rollout_idx": 0,
"run_key": "qiskit__qiskit-terra-5833__p0__r0",
"strict_clean_patch": false,
"tool_calls": 15,
"total_llm_calls": 15,
"trace_path": "/kaggle-root/working/r31/rollouts_X/traces/trace_qiskit__qiskit-terra-5833__p0__r0.json"
}