Landing: 2b7ddfb84111
Project / Subsystem
gcc / vect
Date
2026-09-24
Author
Tamar Christina
Commit
2b7ddfb841114b2783f0b3420fcb96e7687484d9
Source
github
Perf win
No
Breaking
No
All attributes
- project
- gcc
- subsystem
- vect
- patch_id
- —
- commit_hash
- 2b7ddfb841114b2783f0b3420fcb96e7687484d9
- source_type
- github
- headline
- Fix emulated vector costing in GCC's vectorizer
- tldr
- Corrects a bug in GCC's vectorizer that caused ICEs when emulating vector operations without SIMD support.
- author
- Tamar Christina
- outcome
- committed
- performance_win
- false
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • vectorization
- • aarch64
- • optimization
- • bugfix
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-09-24T00:00:00.000Z
This commit resolves an internal compiler error (ICE) in GCC’s vectorizer related to emulated vector operations. When SIMD instructions are unavailable (e.g., with -mgeneral-regs), the vectorizer attempts to emulate them. A recent transition in the costing logic caused it to incorrectly use an old interface, leading to a null pointer dereference. This fix updates the costing code to use the correct SLP node, resolving the ICE and a related test case.