[ARROW-11839] [C++] Rewrite bit-unpacking optimizations using xsimd

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 4.0.0
• Component/s: C++
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/27686
• Assignee: Antoine Pitrou
• Reporter: Antoine Pitrou
• Created: 02/Mar/21 16:26
• Updated: 11/Jan/23 08:22
• Resolved: 13/Apr/21 16:14

Description

Currently, unpacking of fixed-size bit bundles uses custom generated code with SIMD intrinsics (the bpacking files in src/arrow/util).

By leveraging xsimd, we can make the SIMD generated code more generic (e.g. the 256-bit generated code would be able to compile with any 256-bit SIMD ISA supported by xsimd).

Issue Links

• links to: GitHub Pull Request #9614