SIMD fixes malformed UTF-16 strings up to 9x faster, already in Chromium and Node 25
lemire · x · 2026-08-26
A new paper by lemire et al.: fixing ill-formed UTF-16 strings (unpaired surrogates replaced by U+FFFD, as JavaScript and Java store strings) using SIMD — ARM NEON and x64 SSE/AVX2/AVX-512. It hits 18.9 GB/s on an Apple M4 and 7.5 GB/s on Intel Ice Lake, at as little as 0.4 instructions per byte, up to 9x faster than the old approach. Shipped in practice: String.prototype.toWellFormed in Node.js 25 is 5x faster, and the code is in Chromium browsers (Chrome, Edge, Brave); a browser benchmark is linked.
Related event: SIMD Repairs Malformed UTF-16 Strings 9x Faster(2 posts)→
More from Research
- Ran Boltz-2 100 million times to simulate cell biology — dom_beaini · 2026-08-26
- RMSNorm projects activations to a hypersphere, doesn't solve interpretability — _xjdr · 2026-08-26
- LangChain open-sources WikiBench to measure how much codebase wikis help coding agents — LangChain · 2026-08-26
- LpWM Research: Sparse Representations Make Latent Dynamics Easier to Model — randall_balestr · 2026-08-26
- Perplexity Reveals Dream Agents for Continuous Self-Improvement — perplexity_ai · 2026-08-26
- AWS Paper Reveals the 'Handoff Tax' in AI Agent Model Escalation — omarsar0 · 2026-08-26