Landing: 91cc9b3402bb
Project / Subsystem
gcc / gcc
Date
2026-03-03
Author
Richard Biener
Commit
91cc9b3402bb33c1f5c9a0822ff6609aace7b670
Source
github
Perf win
Yes
Breaking
No
All attributes
- project
- gcc
- subsystem
- gcc
- patch_id
- —
- commit_hash
- 91cc9b3402bb33c1f5c9a0822ff6609aace7b670
- source_type
- github
- headline
- Cost each BB vect live lane only once
- tldr
- GCC's vectorizer now costs each basic block's live lane only once, optimizing code generation for SLP trees.
- author
- Richard Biener
- outcome
- committed
- performance_win
- true
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • optimization
- • vectorization
- • slp
- • code generation
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-03-03T00:00:00.000Z
This commit optimizes the costing of live scalar statements within basic blocks during SLP (Superword Level Parallelism) vectorization. By ensuring that each live lane is costed only once, even if it appears in multiple SLP nodes, the compiler can make more accurate decisions about which SLP node to use for code generation. This leads to more efficient vectorization and potentially improved performance.