Landing: ee27c516c7b6

Project / Subsystem

gcc / aarch64

Date

2026-07-13

Author

Dylan Rees

Commit

ee27c516c7b6f0ee364b165aed0c35101da8e77a

Source

github

Perf win

Yes

Breaking

No

All attributes

project
gcc
subsystem
aarch64
patch_id
commit_hash
ee27c516c7b6f0ee364b165aed0c35101da8e77a
source_type
github
headline
AArch64 improves SIMD highpart builtin folding.
tldr
AArch64's SIMD folding now correctly handles uniform 64b vectors for 128b highpart operations.
author
Dylan Rees
outcome
committed
performance_win
true
breaking_change
false
series_id
series_parts
[]
tags
  • aarch64
  • SIMD
  • optimization
  • builtins
discussion_id_link
bugzilla_pr
date
2026-07-13T00:00:00.000Z

The AArch64 backend improves folding of SIMD lowpart builtins into highpart builtins. It now correctly handles cases where a 64-bit wide uniform vector is extended to 128 bits for highpart operations. The change widens uniform vectors before adding them to the call arguments for the equivalent highpart builtin, ensuring correct behavior for these operations.