feat(allocator): introduce BitSet type

[overlookmotel]

#13419 introduced a BitSet type which stores its data in the arena, in the mangler.

This type may be useful in other contexts, so move it from oxc_mangler into oxc_allocator. But put it behind a bitset feature, so only crates which use it pay for it.

[overlookmotel]

• perf(allocator/bitset): store bits in Box<[usize]> #13455
• feat(allocator): add Box::from_non_null method #13454
• perf(allocator/bitset): initialize BitSet with memset #13451
• perf(allocator/bitset): store bits as usizes #13450
• feat(allocator): introduce BitSet type #13449 👈 (View in Graphite)
• main

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[Copilot]

Pull Request Overview

This PR moves the BitSet type from the oxc_mangler crate to the oxc_allocator crate to make it available for reuse in other contexts. The change introduces a new bitset feature flag to avoid adding overhead for crates that don't use this functionality.

Key Changes

• Moved BitSet implementation from oxc_mangler to oxc_allocator
• Added a new bitset feature flag to conditionally include the BitSet type
• Updated imports and dependencies to reflect the new location

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
crates/oxc_mangler/src/lib.rs	Removed local bitset module and imports BitSet from oxc_allocator
crates/oxc_mangler/Cargo.toml	Added bitset feature dependency to oxc_allocator
crates/oxc_allocator/src/lib.rs	Added conditional module and export for BitSet behind bitset feature
crates/oxc_allocator/src/bitset.rs	Added BitSet implementation with documentation comments
crates/oxc_allocator/README.md	Documented the new bitset feature
crates/oxc_allocator/Cargo.toml	Added bitset feature definition

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #13449 will not alter performance

_{Comparing 08-30-feat_allocator_introduce_bitset_type (afa0877) with main (edeebc6)¹}

Summary

✅ 37 untouched benchmarks

Footnotes

1. No successful run was found on main (afa0877) during the generation of this report, so edeebc6 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[graphite-app]

Merge activity

• Aug 31, 4:58 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Aug 31, 5:04 AM UTC: Merged by the Graphite merge queue.