use Borrowed in extract_argument functions

[davidhewitt]

In progress work to close #5392

I realised that using Borrowed allows 'a to outlive 'py in argument extraction. This is not always strictly necessary, but in the case of the async code I'm looking into in #5681 it turns out that it's valid for function arguments to have the 'a lifetime but not the 'py lifetime.

This might also be a performance help by removing the need to have references to pointers on stack frames for the BoundRef stuff. EDIT: looks like it doesn't really affect performance, but I still think it's useful for async code.

[Tpt]

I am not an expert on this code but it seems sensible to me

[Icxolu]

LGTM as well.

It looks like there are not many usages of BoundRef left. Any change that we can adjust them as well and remove it completely?

[davidhewitt]

It looks like there are not many usages of BoundRef left. Any change that we can adjust them as well and remove it completely?

Potentially as a follow up, yes. It's not completely trivial as there are cases like #[pyfunction(pass_module)] which I think allows &Bound<'py, PyModule> as the argument so a TryFrom<Borrowed<'_, 'py, PyModule>> won't quite work.

[codspeed-hq]

Merging this PR will improve performance by 10.21%

Summary

⚡ 1 improved benchmark
✅ 97 untouched benchmarks

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	ordered_dunder_methods	2.6 µs	2.4 µs	+10.21%

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_{Comparing davidhewitt:extract-argument-borrowed (c351cff) with main (c369c0d)}