perf(parser): apply #[cold] attribute to error handling functions

[Boshen]

No description provided.

[graphite-app]

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[Copilot]

Pull Request Overview

Apply the #[cold] attribute to error handling functions in the parser to improve performance by optimizing code layout for hot paths.

• Mark error handling functions as #[cold] to help LLVM optimize instruction cache utilization
• Target functions that only execute during parsing errors or rare edge cases
• Exclude lexer from optimization as requested

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
crates/oxc_parser/src/lib.rs	Mark overlong_error() as cold for handling >4GB files
crates/oxc_parser/src/js/class.rs	Mark check_getter() and check_setter() as cold for validation errors
crates/oxc_parser/src/error_handler.rs	Mark set_unexpected() and unexpected() as cold for error paths

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[Boshen]

Merge activity

• Sep 27, 2:24 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Sep 27, 2:27 PM UTC: Boshen added this pull request to the Graphite merge queue.
• Sep 27, 2:34 PM UTC: Merged by the Graphite merge queue.

[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #14188 will not alter performance

_{Comparing perf/parser-cold-paths (5b74a81) with main (358f2fc)}

Summary

✅ 37 untouched