Landing: 4960fba54554
Project / Subsystem
gcc / gcc/aarch64
Date
2025-12-17
Author
Artemiy Volkov
Commit
4960fba5455498f5253c8da9bceb3466c1ca6b9a
Source
github
Perf win
Yes
Breaking
No
All attributes
- project
- gcc
- subsystem
- gcc/aarch64
- patch_id
- —
- commit_hash
- 4960fba5455498f5253c8da9bceb3466c1ca6b9a
- source_type
- github
- headline
- AArch64: Implement FIRSTP and LASTP SVE instructions
- tldr
- The Arm Scalable Vector Extension (SVE) now supports FIRSTP and LASTP instructions in streaming mode under SME2.2, with new intrinsics and constant folding opt…
- author
- Artemiy Volkov
- outcome
- committed
- performance_win
- true
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • aarch64
- • sve
- • sme
- • intrinsics
- • optimization
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2025-12-17T00:00:00.000Z
The Arm Scalable Vector Extension (SVE) now supports FIRSTP and LASTP instructions in streaming mode under SME2.2. These instructions determine the scalar index of the first or last true predicate element. New intrinsics have been added, along with constant folding optimizations. The patterns for these new instructions are implemented using UNSPECs as they can’t be expressed in terms of standard RTL.