Landing: ca800bd07d2d
Project / Subsystem
gcc / aarch64
Date
2026-09-22
Author
Wilco Dijkstra
Commit
ca800bd07d2d0eb1f00dcb3314aaf34df8230053
Source
github
Perf win
Yes
Breaking
No
All attributes
- project
- gcc
- subsystem
- aarch64
- patch_id
- —
- commit_hash
- ca800bd07d2d0eb1f00dcb3314aaf34df8230053
- source_type
- github
- headline
- AArch64: Use specific operand for atomic_store
- tldr
- Improves common subexpression elimination for atomic stores by using a more specific operand.
- author
- Wilco Dijkstra
- outcome
- committed
- performance_win
- true
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • aarch64
- • optimization
- • atomics
- • cse
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-09-22T00:00:00.000Z
The generic atomic_store<mode> pattern in the AArch64 backend used general_operand, which prevented common subexpression elimination (CSE) when the store value was an immediate. This commit replaces general_operand with aarch64_reg_or_zero, a more specific operand that allows CSE to function correctly, potentially leading to more optimized code.