Landing: 6becc7cc2c06
Project / Subsystem
gcc / gcc/simplify-rtx
Date
2026-03-31
Author
Bohan Lei
Commit
6becc7cc2c06b3941d829e08100a6ff70cc55262
Source
github
Perf win
Yes
Breaking
No
All attributes
- project
- gcc
- subsystem
- gcc/simplify-rtx
- patch_id
- —
- commit_hash
- 6becc7cc2c06b3941d829e08100a6ff70cc55262
- source_type
- github
- headline
- Simplify RTX comparisons of bitwise operations with constants.
- tldr
- GCC now simplifies certain comparisons involving bitwise AND/OR operations with constants, potentially fixing an ICE on RISC-V.
- author
- Bohan Lei
- outcome
- committed
- performance_win
- true
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • optimization
- • risc-v
- • compiler
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-03-31T00:00:00.000Z
This patch introduces simplifications for expressions of the form (cmp (and/ior x C1) C2) within GCC’s simplify-rtx pass. By analyzing the relationships between the constants C1 and C2, the compiler can determine cases where the comparison can never be true, allowing for optimization. This change addresses a reported internal compiler error (ICE) on RISC-V and improves code generation in specific scenarios.