Landing: 2601cb4d2736

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Project / Subsystem

gcc / rs6000

Date

2026-07-09

Author

Surya Kumari Jangala

Commit

2601cb4d27364e2ae5c0eb4f53e186e0e0ecadde

Source

github

Perf win

Breaking

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All attributes

project: gcc
subsystem: rs6000
patch_id: —
commit_hash: 2601cb4d27364e2ae5c0eb4f53e186e0e0ecadde
source_type: github
headline: Add -mdense-math option to control Dense Math Facility instructions.
tldr: New -mdense-math option allows control over Dense Math Facility (DMF) instruction emission on RS6000 targets.
author: Surya Kumari Jangala
outcome: committed
performance_win: false
breaking_change: false
series_id: —
series_parts: []
tags: • rs6000
• powerpc
• new-option
discussion_id_link: —
bugzilla_pr: —
url: https://github.com/gcc-mirror/gcc/commit/2601cb4d27364e2ae5c0eb4f53e186e0e0ecadde
date: 2026-07-09T00:00:00.000Z

A new compiler option, -mdense-math, has been introduced for RS6000 targets to explicitly enable or disable the use of the Dense Math Facility (DMF) instructions. When targeting the ‘future’ CPU, DMF is automatically enabled by default unless explicitly disabled. Attempting to use -mdense-math on a non-future target now results in a hard error, providing clearer control over the generation of these specialized instructions.