Validating UTF-8 In Less Than One Instruction Per Byte

2020/10/06 by John Keiser, Daniel Lemire · 2 voices
Computer Science · #cs.DB

paper · pdf · doi:10.1002/spe.2920

arxiv published 2020/10/06 · arxiv updated 2026/04/21

Abstract

The majority of text is stored in UTF-8, which must be validated on ingestion. We present the lookup algorithm, which outperforms UTF-8 validation routines used in many libraries and languages by more than 10 times using commonly available SIMD instructions. To ensure reproducibility, our work is freely available as open source software.

Cited by

• Fixing ill-formed UTF-16 strings with SIMD instructions

Discussions

• Validating UTF-8 in Less Than One Instruction per Byte [hn, 2 points, 0 comments]
• Validating UTF-8 in Less Than One Instruction per Byte [hn, 1 points, 0 comments]

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