Landing: 28f6899c51c4
Project / Subsystem
gcc / match-sat-alu.pd
Date
2026-09-05
Author
Kyrylo Tkachov
Commit
28f6899c51c456302943d549ab78d9bb022f36d8
Source
github
Perf win
Yes
Breaking
No
All attributes
- project
- gcc
- subsystem
- match-sat-alu.pd
- patch_id
- —
- commit_hash
- 28f6899c51c456302943d549ab78d9bb022f36d8
- source_type
- github
- headline
- Recognize complement tests for unsigned saturating addition.
- tldr
- GCC can now recognize complement tests for unsigned saturating addition, optimizing it to a single instruction on AArch64.
- author
- Kyrylo Tkachov
- outcome
- committed
- performance_win
- true
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • optimization
- • aarch64
- • vectorization
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-09-05T00:00:00.000Z
The match-sat-alu.pd pattern matching has been extended to recognize comparisons involving the complement of an operand for unsigned saturating addition. This allows the compiler to replace code like X > ~Y ? MAX : X + Y with a single uqadd instruction on AArch64, reducing four vector operations to one.