refactor(allocator/vec): use assert_unchecked over unreachable_unchecked

[overlookmotel]

Pure refactor. Use the newer assert_unchecked function instead of unreachable_unchecked. This does exactly the same thing, but is clearer.

Also add a comment as to why this code exists.

[overlookmotel]

• refactor(allocator/vec): use assert_unchecked over unreachable_unchecked #15511 👈 (View in Graphite)
• main

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[overlookmotel]

Small change, so merging without review.

[Copilot]

Pull Request Overview

This PR refactors the pointer null-check assertions in Vec::as_ptr() and Vec::as_mut_ptr() methods to use the more direct std::hint::assert_unchecked function instead of the previous pattern using hint::unreachable_unchecked().

• Replaced conditional unreachable_unchecked() calls with direct assert_unchecked() calls
• Updated the import from hint to hint::assert_unchecked for direct function access
• Simplified and modernized the implementation while maintaining identical semantics

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[codspeed-hq]

CodSpeed Performance Report

Merging #15511 will not alter performance

_{Comparing 11-09-refactor_allocator_vec_use_assert_unchecked_over_unreachable_unchecked_ (ffa9d76) with main (6f3cd77)¹}

Summary

✅ 37 untouched

Footnotes

1. No successful run was found on main (25d577e) during the generation of this report, so 6f3cd77 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[overlookmotel]

-2% perf regression on codegen benchmarks is just noise. These benchmarks are really noisy: https://codspeed.io/oxc-project/oxc/benchmarks/tasks/benchmark/benches/codegen.rs::codegen::bench_codegen::codegen%5Bcal.com.tsx%5D?runnerMode=Instrumentation&branchId=6910600bd9fb6b6c197529f3

[overlookmotel]

Merge activity

• Nov 9, 10:54 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 9, 10:54 AM UTC: overlookmotel added this pull request to the Graphite merge queue.
• Nov 9, 11:00 AM UTC: Merged by the Graphite merge queue.