Landing: ba472b886b31
Project / Subsystem
gcc / tree-optimization
Date
2026-08-29
Author
Lunex
Commit
ba472b886b31046afba1df687b65bd862b087240
Source
github
Perf win
No
Breaking
No
All attributes
- project
- gcc
- subsystem
- tree-optimization
- patch_id
- —
- commit_hash
- ba472b886b31046afba1df687b65bd862b087240
- source_type
- github
- headline
- Fix missing may_be_zero check in final value replacement
- tldr
- Corrected a scalar evolution analysis to prevent incorrect XOR parity mask computation.
- author
- Lunex
- outcome
- committed
- performance_win
- false
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • optimization
- • loop analysis
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-08-29T00:00:00.000Z
The final value replacement pass in the tree optimizer previously failed to check niter_desc.may_be_zero. This omission could lead to incorrect computation of the XOR parity mask when a loop might exit on its first iteration. The fix ensures this check is performed, preventing the use of invalid iteration counts.