Landing: f8eb22d8408b
Project / Subsystem
gcc / match
Date
2026-07-17
Author
Neal Patalay
Commit
f8eb22d8408b25f337fad514aa8f47fe24f051d9
Source
github
Perf win
Yes
Breaking
No
All attributes
- project
- gcc
- subsystem
- match
- patch_id
- —
- commit_hash
- f8eb22d8408b25f337fad514aa8f47fe24f051d9
- source_type
- github
- headline
- match: Simplify sign tests for MIN and BIT_IOR
- tldr
- Optimizes comparisons involving MIN and bitwise OR operations by simplifying sign tests.
- author
- Neal Patalay
- outcome
- committed
- performance_win
- true
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • optimization
- • compiler
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-07-17T00:00:00.000Z
The match.pd patterns now simplify comparisons against zero for MIN(a, b) and a | b when b is known to be non-negative. These operations’ signs then depend solely on ‘a’, allowing optimization of MIN (a, b) cmp 0 and (a | b) cmp 0 to a cmp 0. This optimization is now performed earlier in the compilation process.