perf(codegen): avoid allocation in PrivateIdentifier gen when not mangling

[camc314]

we previously always called into_compact_str when not mangling. This is unneccessary as we can just print from the string slice.

[camc314]

• perf(codegen): restructure print_comments to avoid index comparisons in loop #17402
• perf(codegen): use print_ascii_byte in more places #17401
• perf(codegen): avoid allocation in PrivateIdentifier gen when not mangling #17395 👈 (View in Graphite)
• main

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[Copilot]

Pull request overview

This PR optimizes the code generation for private identifiers by avoiding unnecessary string allocation in the non-mangling case. Previously, the code always called into_compact_str() to create a new CompactStr, even when no mangling was needed.

Key changes:

• Refactored the PrivateIdentifier generation logic to conditionally handle mangled vs. non-mangled cases
• In the non-mangling case, the code now directly prints from the string slice without creating a CompactStr
• In the mangling case, the logic remains functionally equivalent with the same allocation behavior

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[codspeed-hq]

CodSpeed Performance Report

Merging #17395 will not alter performance

_{Comparing c/12-27-perf_codegen_avoid_allocation_in_privateidentifier_gen_when_not_mangling (834155b) with main (585ddf8)}

Summary

✅ 42 untouched
⏩ 3 skipped¹

Footnotes

1. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[graphite-app]

Merge activity

• Dec 28, 5:00 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Dec 28, 5:06 AM UTC: Merged by the Graphite merge queue.