refactor(allocator)!: make Address::from_ptr an unsafe method

[overlookmotel]

A further step in refactoring Address to make it more robust and performant.

Make Address::from_ptr an unsafe method, with the safety invariant that the pointer must be non-null. This:

1. Further discourages use of Address::from_ptr - GetAddress::address or UnstableAddress::unstable_address should be used instead.
2. Opens the door to changing Address's inner type from usize to NonZeroUsize, which will reduce Option<Address> from 16 bytes to 8.

[overlookmotel]

• refactor(allocator)!: make Address::from_ptr an unsafe method #16021 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #16021 will not alter performance

_{Comparing 11-24-refactor_allocator_make_address_from_ptr_an_unsafe_method (1b1200a) with main (3fe5225)¹}

Summary

✅ 42 untouched
⏩ 3 skipped²

Footnotes

1. No successful run was found on main (b8bf404) during the generation of this report, so 3fe5225 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[overlookmotel]

Merge activity

• Nov 24, 1:44 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Nov 24, 1:44 AM UTC: overlookmotel added this pull request to the Graphite merge queue.
• Nov 24, 1:57 AM UTC: Merged by the Graphite merge queue.

[Copilot]

Pull request overview

This PR refactors the Address API by making Address::from_ptr an unsafe method with a non-null pointer safety invariant. This change discourages direct use of from_ptr and paves the way for future optimization where Address could use NonZeroUsize internally, reducing Option<Address> from 16 to 8 bytes.

• Made Address::from_ptr unsafe, requiring callers to ensure the pointer is non-null
• Updated all call sites in generated code to wrap from_ptr calls in unsafe blocks
• Optimized GetAddress implementation for Box<'_, T> to avoid redundant unsafe block

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 1 comment.

File	Description
crates/oxc_allocator/src/address.rs	Modified from_ptr signature to be unsafe, added safety documentation, and optimized GetAddress impl for Box<'_, T> by using NonNull::addr().get() directly
crates/oxc_traverse/src/generated/ancestor.rs	Updated all GetAddress implementations for *Without* types to wrap Address::from_ptr(self.0) calls in unsafe blocks
crates/oxc_traverse/scripts/lib/ancestor.mjs	Updated code generator to emit unsafe { Address::from_ptr(self.0) } in generated GetAddress implementations

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