Landing: 26e88fe809de
Project / Subsystem
gcc / middle-end
Date
2026-04-17
Author
Tamar Christina
Commit
26e88fe809de0f1a1812c99e2e0106afb03257b3
Source
github
Impact
7/10
Perf win
No
Breaking
No
All attributes
- project
- gcc
- subsystem
- middle-end
- patch_id
- —
- commit_hash
- 26e88fe809de0f1a1812c99e2e0106afb03257b3
- source_type
- github
- headline
- Middle-end: Disable CRC pass under -Os when CRC optabs are missing.
- tldr
- Disables the CRC table-based expansion during optimization for size (`-Os`) when the target architecture lacks specific CRC instruction support.
- why_it_matters
- Prevents significant code size increases caused by CRC table expansion on architectures without native CRC instructions when optimizing for size.
- author
- Tamar Christina
- impact_score
- 7
- impact_rationale
- Significant impact on code size when optimizing for size on certain architectures without CRC instructions.
- outcome
- committed
- performance_win
- false
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • optimization
- • CRC
- • code size
- • aarch64
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-04-17T00:00:00.000Z
When compiling with -Os for architectures lacking CRC optabs, the CRC pass can significantly increase code size by generating a large lookup table. This commit disables the CRC table-based expansion in such scenarios, preventing the code size regression. It also adds new tests for CRC functionality on AArch64.