perf(ast/estree): optimize serializing strings to JSON

[overlookmotel]

Optimize printing strings in ESTree serializer.

The main optimizations are:

1. Search for characters which need escaping in batches of 16 bytes, to speed up search over longer strings.
2. Move the initial search for characters which need escaping into a tight loop.

Additionally:

3. Tighten up the rest of the code to remove bounds checks.

[overlookmotel]

• perf(ast/estree): optimize serializing strings to JSON #11070 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #11070 will not alter performance

_{Comparing 05-16-perf_ast_estree_optimize_serializing_strings_to_json (8f8d823) with main (c29b1b8)}

Summary

✅ 36 untouched benchmarks

[overlookmotel]

Not much effect on estree benchmark, but I imagine it'd show a bigger gain on files with many longer strings (e.g. content-heavy websites).

[Boshen]

Merge activity

• May 16, 11:30 AM EDT: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• May 16, 11:30 AM EDT: Boshen added this pull request to the Graphite merge queue.
• May 16, 11:37 AM EDT: Merged by the Graphite merge queue.