Landing: 7034f85fb657
Project / Subsystem
gcc / middle-end
Date
2025-11-28
Author
Kito Cheng
Commit
7034f85fb6577ac48693f0606b7e33fef41a1b74
Source
github
Perf win
Yes
Breaking
No
All attributes
- project
- gcc
- subsystem
- middle-end
- patch_id
- —
- commit_hash
- 7034f85fb6577ac48693f0606b7e33fef41a1b74
- source_type
- github
- headline
- Middle-end: Optimize reversed CRC table-based implementation
- tldr
- GCC now generates faster table-based CRC implementations by pre-reversing the lookup table.
- author
- Kito Cheng
- outcome
- committed
- performance_win
- true
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • optimization
- • crc
- • middle-end
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2025-11-28T00:00:00.000Z
GCC’s middle-end now optimizes reversed CRC calculations by generating a reversed polynomial lookup table directly. This eliminates the need for explicit bit reflection before and after the CRC computation, improving code generation for all targets using table-based reversed CRCs. The change removes the overhead of reflecting input data and CRC values, resulting in faster CRC calculations.