Landing: f152cf1734f8

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Project / Subsystem

gcc / gcc

Date

2026-06-11

Author

Naveen

Commit

f152cf1734f8087b982605ce93d4fb048283564e

Source

github

Perf win

Yes

Breaking

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project: gcc
subsystem: gcc
patch_id: —
commit_hash: f152cf1734f8087b982605ce93d4fb048283564e
source_type: github
headline: AArch64 GCC uses MOVI for low-64-bit integer SIMD constants.
tldr: GCC on AArch64 now generates more efficient code for certain 128-bit SIMD integer constants by using the `MOVI` instruction.
author: Naveen
outcome: committed
performance_win: true
breaking_change: false
series_id: —
series_parts: []
tags: • aarch64
• simd
• optimization
• performance
discussion_id_link: —
bugzilla_pr: —
url: https://github.com/gcc-mirror/gcc/commit/f152cf1734f8087b982605ce93d4fb048283564e
date: 2026-06-11T00:00:00.000Z

The AArch64 backend of GCC now optimizes the materialization of specific 128-bit integer SIMD constants. When the constant has a duplicated scalar value in its low 64 bits and zero in its high 64 bits, GCC will now emit the more efficient MOVI instruction. This improves code generation for Advanced SIMD (AdvSIMD) operations, eliminating the need for more complex instruction sequences.