Landing: 54dd6575fa5b
Project / Subsystem
gcc / gcc/tree-optimization
Date
2026-07-07
Author
Naveen
Commit
54dd6575fa5ba7554396039820bee88d4dddab6d
Source
github
Perf win
Yes
Breaking
No
All attributes
- project
- gcc
- subsystem
- gcc/tree-optimization
- patch_id
- —
- commit_hash
- 54dd6575fa5ba7554396039820bee88d4dddab6d
- source_type
- github
- headline
- Improve CDCE memset optimization for {0, N} ranges
- tldr
- GCC's CDCE optimization now better handles memset calls with {0, N} length ranges.
- author
- Naveen
- outcome
- committed
- performance_win
- true
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • optimization
- • gcc
- • memset
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-07-07T00:00:00.000Z
This patch enhances the CDCE (Conditional Dead Code Elimination) optimization to better support memset calls where the length is known to be exactly 0 or another constant N. Previously, this optimization only handled lengths in ranges [0, 1]. The update allows the pass to specialize the memset call to a constant length N, improving code generation for these specific cases. New test cases are added to verify the fix.