Landing: 4ddae2a94a03

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Project / Subsystem

gcc / aarch64

Date

2026-02-26

Author

Artemiy Volkov

Commit

4ddae2a94a032d77ef5564117e9906247a29a05f

Source

github

Perf win

Yes

Breaking

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All attributes

project: gcc
subsystem: aarch64
patch_id: —
commit_hash: 4ddae2a94a032d77ef5564117e9906247a29a05f
source_type: github
headline: AArch64 now initializes vectors from a common starting subsequence.
tldr: GCC now initializes AArch64 vectors more efficiently when elements can be generated from a common starting subsequence.
author: Artemiy Volkov
outcome: committed
performance_win: true
breaking_change: false
series_id: —
series_parts: []
tags: • aarch64
• vectorization
• optimization
discussion_id_link: —
bugzilla_pr: —
url: https://github.com/gcc-mirror/gcc/commit/4ddae2a94a032d77ef5564117e9906247a29a05f
date: 2026-02-26T00:00:00.000Z

This commit enables more efficient vector initialization on AArch64 when elements can be generated from a common starting subsequence. It detects the shortest subsequence and then duplicates it using vec_duplicate, reducing the number of insert instructions. This optimization improves code generation for vector constructors with repeating patterns.