perf: prefix trimming for case-fold literals — Teddy instead of AC#141
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When literal extraction produces >32 incomplete prefix literals (e.g., 225 case-fold expanded variants), trim to 4-byte prefixes and deduplicate. This reduces literal count to fit Teddy (≤32 patterns, SIMD fast) instead of falling through to Aho-Corasick (slower sequential scan). Skip for AllComplete literals (exact matches) — those go to Teddy/AC directly. LangArena suspicious pattern: - Before: 225 literals → AC prefilter → 117ms - After: 17 literals → Teddy SIMD → 10.9ms (10.7x faster, 1.8x from Rust)
Benchmark ComparisonComparing Summary:
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Summary
(?i)expansion produces >32 incomplete prefix literals, trims to 4-byte prefixes and deduplicates. Reduces to ~17 literals that fit Teddy SIMD instead of slower Aho-Corasick.LangArena
suspicious((?i)etc/passwd|wp-admin|\.\./): 117ms → 10.9ms (10.7x faster, 1.8x from Rust, was 54x).Verified: Rust uses identical optimization (
optimize_for_prefix_by_preference) producing same 17 four-byte prefixes → Teddy.Test plan