perf(mangler): reduce hash table lookups

[overlookmotel]

When getting the list of symbol names for slots, pre-prepare a single hash set of all unavailable symbol names. Then in the loop which generates symbol names, only 1 hash table lookup is required for each name.

[overlookmotel]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
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• perf(mangler): reduce hash table lookups #8558 👈 (View in Graphite)
• perf(mangler): optimize base54 function #8557
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #8558 will not alter performance

_{Comparing 01-17-perf_mangler_reduce_hash_table_lookups (d2a510b) with 01-17-perf_mangler_optimize_base54_function (24bbdb7)}

Summary

✅ 32 untouched benchmarks

[overlookmotel]

Better on 2 benchmarks (+2%) but worse on 1 (-1%). Not worthwhile.