feat(tasks): track allocations for semantic

[camchenry]

Now that we've tested the allocation tracking for parsing for a while and it has been fairly stable, I'd like to start tracking allocations for Semantic as well. Tracking the arena allocations for semantic is non-trivial unfortunately due to the usage of the allocator internally. Once we can supply an allocator to SemanticBuilder it will be easy to start tracking allocations.

[camchenry]

• feat(allocs): add callsite tracking for allocations #13090
• feat(tasks): track allocations for semantic #13012 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #13012 will not alter performance

_{Comparing 08-12-feat_tasks_track_allocations_for_semantic (b2a534c) with main (1385c71)¹}

Summary

✅ 34 untouched benchmarks

Footnotes

1. No successful run was found on main (4f2cc96) during the generation of this report, so 1385c71 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[overlookmotel]

Number of arena reallocations happening in SemanticBuilder could be really interesting here.

Semantic uses a separate Allocator. You'd need to get access to it somehow to find out how many allocations it makes.

[camchenry]

Number of arena reallocations happening in SemanticBuilder could be really interesting here.

Semantic uses a separate Allocator. You'd need to get access to it somehow to find out how many allocations it makes.

It looks like this would be a pretty non-trivial change. I think we'd need to update the public API to match Parser where it accepts an allocator reference and stores it internally? For now, I'm just going to set this up to track system allocations for now so we at least have some information available.

[Copilot]

Pull Request Overview

This PR adds allocation tracking for the Semantic analyzer to the memory allocation tracking task, extending the existing parser allocation tracking functionality.

• Introduces semantic analysis allocation tracking alongside the existing parser tracking
• Refactors the code to support tracking both parser and semantic operations separately
• Creates separate snapshot files for parser and semantic allocation statistics

Reviewed Changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated 3 comments.

File	Description
tasks/track_memory_allocations/src/lib.rs	Adds semantic tracking logic, refactors stats collection into reusable functions, and creates separate output for parser vs semantic allocations
tasks/track_memory_allocations/allocs_semantic.snap	New snapshot file containing semantic allocation statistics
tasks/track_memory_allocations/Cargo.toml	Adds oxc_semantic dependency

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[camchenry]

Going to close for now and will revisit at a later point.