Landing: eef42c68c7f6
Project / Subsystem
gcc / ifcvt
Date
2026-07-30
Author
Kyrylo Tkachov
Commit
eef42c68c7f66835747f82e4532a26d7a0f6bb98
Source
github
Perf win
Yes
Breaking
No
All attributes
- project
- gcc
- subsystem
- ifcvt
- patch_id
- —
- commit_hash
- eef42c68c7f66835747f82e4532a26d7a0f6bb98
- source_type
- github
- headline
- ifcvt: Do not clobber live condition-code register
- tldr
- Fixes if-conversion to avoid destroying condition codes needed by later branches.
- author
- Kyrylo Tkachov
- outcome
- committed
- performance_win
- true
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • optimization
- • aarch64
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-07-30T00:00:00.000Z
The if-conversion pass incorrectly destroyed condition-code registers that were still live, causing incorrect flag values to be used by subsequent instructions. This change ensures that if-conversion respects the liveness of condition-code registers, preventing it from clobbering them and thus fixing bugs like PR126501 and PR126747.