perf(minifier): prealloc template exprs vec

[camchenry]

Small preallocation optimization. Found this mainly to demonstrate that the minifier allocation tracking is working as expected.

[camchenry]

• perf(minifier): prealloc template exprs vec #13410 👈 (View in Graphite)
• feat(allocs): track allocations for minifier #13408
• refactor(allocs): allow capturing multiple stats at once #13407
• main

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #13410 will not alter performance

_{Comparing 08-29-perf_minifier_prealloc_template_exprs_vec (60dd9c9) with main (7e78e39)¹}

Summary

✅ 37 untouched benchmarks

Footnotes

1. No successful run was found on main (60dd9c9) during the generation of this report, so 7e78e39 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[Copilot]

Pull Request Overview

This PR adds a small preallocation optimization to the minifier by preallocating the template expressions vector with the known capacity. The change reduces memory reallocations during template literal processing.

• Preallocates the expressions vector with expression_count capacity instead of starting with an empty vector

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
tasks/track_memory_allocations/allocs_minifier.snap	Updates allocation tracking snapshot showing reduced arena reallocations from 70354 to 70117
crates/oxc_minifier/src/peephole/replace_known_methods.rs	Preallocates expressions vector with known capacity in template literal optimization

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[Boshen]

Merge activity

• Sep 3, 12:55 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Sep 3, 12:55 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Sep 3, 1:01 AM UTC: Merged by the Graphite merge queue.