#crc #simd #checksum #hash #lookup-tables

crc32-aixm-fast

SIMD-powered implementation of CRC-32/AIXM (CRC-32Q)

3 releases (breaking)

0.4.0 Nov 7, 2024
0.3.0 Oct 20, 2024
0.2.0 Oct 20, 2024

#2695 in Algorithms

Download history 220/week @ 2024-10-16 44/week @ 2024-10-23 13/week @ 2024-10-30 128/week @ 2024-11-06

405 downloads per month

MIT license

8KB
64 lines

crc32-aixm-fast

SIMD implementation of CRC-32/AIXM (CRC-32Q), with table and loop fallbacks.

This crate was generated by crc-fast-rs.

Principle of operation

TL;DR: uses SIMD if available, otherwise falls back seamlessly to a lookup table algorithm.

  • If using hash, will use SIMD if the CPU is capable
    • x86-64 CPU:s with the following CPU flags are supported (runtime detection):
      • pclmulqdq
      • sse4.1
    • aarch64 CPU:s with the following CPU flags are supported:
      • nano
      • aes
    • IMPORTANT: aarch64 does not use runtime feature detection and has to be built with a compatible target-cpu to use SIMD, unlike x86-64.
  • If using hash with an incompatible CPU the fallback algorithm will be invoked. If the table-fallback feature is active the fallback is based on a lookup table, otherwise a simple loop (slowest option). Deactivating table-fallback (default enabled) can be useful when memory is very scarce, as the lookup table requires a small amount of extra RAM.
  • If table-fallback feature is enabled, it can be manually invoked by hash_table (not recommended in the typical case).
  • Similarly, hash_simple can be used to force the loop algorithm (also not recommended in the typical case).

Usage

let res: u32 = crc32_aixm_fast::hash(&my_binary_slice);

There is no "update"-like functionality yet, since doing this with arbitrarily lengths can be tricky with SIMD and destroy performance.

Dependencies

~37KB