Avoid clone on entry to BasisTranslator#14761
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The Rust-space method takes ownership of the `DAGCircuit` so that the return type can be a unified `PyResult<DAGCircuit>`, even though in the majority case, the pass actually builds a completely new DAG. This unfortunately requires an implicit clone on entry from Python space, even though there is no situation where the clone is actually _necessary_; the rebuild form never mutates the input, and in the fast-return paths, Python space can simply continue using the reference to a `DAGCircuit` it already holds.
jakelishman
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raynelfss
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Aug 1, 2025
The Rust-space method takes ownership of the `DAGCircuit` so that the return type can be a unified `PyResult<DAGCircuit>`, even though in the majority case, the pass actually builds a completely new DAG. This unfortunately requires an implicit clone on entry from Python space, even though there is no situation where the clone is actually _necessary_; the rebuild form never mutates the input, and in the fast-return paths, Python space can simply continue using the reference to a `DAGCircuit` it already holds.
raynelfss
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that referenced
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Aug 1, 2025
The Rust-space method takes ownership of the `DAGCircuit` so that the return type can be a unified `PyResult<DAGCircuit>`, even though in the majority case, the pass actually builds a completely new DAG. This unfortunately requires an implicit clone on entry from Python space, even though there is no situation where the clone is actually _necessary_; the rebuild form never mutates the input, and in the fast-return paths, Python space can simply continue using the reference to a `DAGCircuit` it already holds.
raynelfss
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that referenced
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Aug 4, 2025
The Rust-space method takes ownership of the `DAGCircuit` so that the return type can be a unified `PyResult<DAGCircuit>`, even though in the majority case, the pass actually builds a completely new DAG. This unfortunately requires an implicit clone on entry from Python space, even though there is no situation where the clone is actually _necessary_; the rebuild form never mutates the input, and in the fast-return paths, Python space can simply continue using the reference to a `DAGCircuit` it already holds.
aaryav-3
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Oct 21, 2025
The Rust-space method takes ownership of the `DAGCircuit` so that the return type can be a unified `PyResult<DAGCircuit>`, even though in the majority case, the pass actually builds a completely new DAG. This unfortunately requires an implicit clone on entry from Python space, even though there is no situation where the clone is actually _necessary_; the rebuild form never mutates the input, and in the fast-return paths, Python space can simply continue using the reference to a `DAGCircuit` it already holds.
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The Rust-space method takes ownership of the
DAGCircuitso that the return type can be a unifiedPyResult<DAGCircuit>, even though in the majority case, the pass actually builds a completely new DAG. This unfortunately requires an implicit clone on entry from Python space, even though there is no situation where the clone is actually necessary; the rebuild form never mutates the input, and in the fast-return paths, Python space can simply continue using the reference to aDAGCircuitit already holds.Summary
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