Landing: c5fe62b9f1ed

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Project / Subsystem

gcc / libcpp

Date

2026-08-12

Author

Wilco Dijkstra

Commit

c5fe62b9f1ed3362c0b966c3f0e60f27b7d85572

Source

github

Perf win

Yes

Breaking

View on GitHub →

All attributes

project: gcc
subsystem: libcpp
patch_id: —
commit_hash: c5fe62b9f1ed3362c0b966c3f0e60f27b7d85572
source_type: github
headline: libcpp: Optimize AArch64 search_line_neon for performance
tldr: Optimized AArch64 search_line_neon in libcpp significantly improves performance on Neoverse processors.
author: Wilco Dijkstra
outcome: committed
performance_win: true
breaking_change: false
series_id: —
series_parts: []
tags: • aarch64
• performance
• libcpp
• optimization
discussion_id_link: —
bugzilla_pr: —
url: https://github.com/gcc-mirror/gcc/commit/c5fe62b9f1ed3362c0b966c3f0e60f27b7d85572
date: 2026-08-12T00:00:00.000Z

The AdvSIMD search_line_neon implementation in libcpp has been significantly optimized for AArch64 processors. The new version focuses on quickly finding matches in short lines with reduced initialization overhead. This results in performance improvements of approximately 54% on Neoverse V2 and 42% on Neoverse N1.