Qiskit / qiskit / 17069935806

88%

Build Type

push

github

Committed by web-flow

Commit Message

Add Python free path to CheckMap pass (#14885)

* Add Python free path to CheckMap pass

The CheckMap transpiler pass only requires Python in the presence of
control flow operations to recurse through the blocks. Otherwise Python
isn't required and there is also a potentially slightly more efficient
execution path without the need for Python. This commit adds a pure rust
function that performs the CheckMap functionality when control flow isn't
present and the Python entrypoint uses this if the dag has no control flow.
This also gives us an entry point for the C transpiler to run check map
if needed.

* Handle the _FakeTarget

In the case the transpiler is invoked with just a coupling map and no
gate constraints a _FakeTarget is created which overloads the accessor
methods for the methods like `build_coupling_map` but don't actually
store any data. The idea behind the class was to provide a compatibility
layer between the legacy user interface and the pass interfaces which
have normalized on using a target. However, this is a Python-centric
view and the _FakeTarget can't be represented in Rust. This PR which
moves more of the logic into Rust wasn't able to recognize any details
in the fake target. This commit handles it explicitly by building a
dummy target to populate a full target in Rust that the pass can
actually use.

* Box is a control flow op too

* Fix lint

* Remove lifetime parameter from recurse()

* Remove qargs property

* Remove unused import

Run Details

51 of 51 new or added lines in 4 files covered. (100.0%)

22 existing lines in 4 files now uncovered.

88103 of 99818 relevant lines covered (88.26%)

504828.46 hits per line