Landing: c07fc7b5c698
Project / Subsystem
gcc / match
Date
2026-08-06
Author
Kyrylo Tkachov
Commit
c07fc7b5c69884adbfea21c3db08a9583f664377
Source
github
Perf win
Yes
Breaking
No
All attributes
- project
- gcc
- subsystem
- match
- patch_id
- —
- commit_hash
- c07fc7b5c69884adbfea21c3db08a9583f664377
- source_type
- github
- headline
- Fold idioms involving negation and bitwise operations.
- tldr
- Compiler now recognizes and simplifies arithmetic idioms involving negation and bitwise operations for improved performance.
- author
- Kyrylo Tkachov
- outcome
- committed
- performance_win
- true
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • optimization
- • pattern matching
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-08-06T00:00:00.000Z
The compiler’s pattern matching system has been enhanced to recognize and fold two arithmetic idioms that are built from the negation of a value. These optimizations, which involve combinations of addition, bitwise AND, and negation, can lead to more efficient code generation, particularly for operations like rounding up to the nearest power of two. The changes also include updates to test cases and ensure that the optimizations do not interfere with overflow sanitization.