Landing: bc19036af435
Project / Subsystem
gcc / gcc
Date
2026-05-18
Author
Jeff Law
Commit
bc19036af435b239c0118e9b83be1d4f58aaea2b
Source
github
Perf win
No
Breaking
No
All attributes
- project
- gcc
- subsystem
- gcc
- patch_id
- —
- commit_hash
- bc19036af435b239c0118e9b83be1d4f58aaea2b
- source_type
- github
- headline
- Improve ext-dce's live bit tracking for IOR/AND with a constant argument
- tldr
- Improves dead code elimination by tracking live bits for IOR/AND operations with constant arguments.
- author
- Jeff Law
- outcome
- committed
- performance_win
- false
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • risc-v
- • optimization
- • dead code elimination
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-05-18T00:00:00.000Z
This commit enhances the dead code elimination (DCE) pass by improving live bit tracking for logical IOR and AND operations with constant arguments. When bits are masked off or unconditionally turned on via these operations, the patch ensures that the masked-off bits are not considered live-in for the other input. This allows the compiler to eliminate unnecessary extension operations, leading to more optimized code, particularly on RISC-V.