Landing: 789d24cd259e
Project / Subsystem
gcc / gcc/sched-deps
Date
2026-07-27
Author
Kyrylo Tkachov
Commit
789d24cd259e0e1e8e5af512565fa59daae5307d
Source
github
Perf win
Yes
Breaking
No
All attributes
- project
- gcc
- subsystem
- gcc/sched-deps
- patch_id
- —
- commit_hash
- 789d24cd259e0e1e8e5af512565fa59daae5307d
- source_type
- github
- headline
- Improves scheduler efficiency by reusing register dependency arrays.
- tldr
- Reduces scheduler setup time by pooling and reusing register dependency data structures.
- author
- Kyrylo Tkachov
- outcome
- committed
- performance_win
- true
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • optimization
- • scheduler
- • compile-time
- • gcc
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-07-27T00:00:00.000Z
The GCC region scheduler previously allocated and zeroed new dependency descriptor arrays for each basic block within a region, leading to quadratic complexity in large functions. This commit introduces a pool for these deps_reg_entries arrays. After use, arrays are returned to the pool and reused for subsequent regions, significantly reducing allocation and zeroing overhead. This optimization improves compiler performance, particularly for large functions, with no impact on the generated code.