Landing: 5de59c6d8267

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Project / Subsystem

gcc / gcc

Date

2026-04-26

Author

Jeff Law

Commit

5de59c6d8267ddfefec34317a67fa96b4f0900e2

Source

github

Perf win

Yes

Breaking

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All attributes

project: gcc
subsystem: gcc
patch_id: —
commit_hash: 5de59c6d8267ddfefec34317a67fa96b4f0900e2
source_type: github
headline: Improve equality comparisons of a logical AND expressions
tldr: GCC on RISC-V now optimizes equality comparisons of logical AND results, potentially reducing code size and improving instruction scheduling.
author: Jeff Law
outcome: committed
performance_win: true
breaking_change: false
series_id: —
series_parts: []
tags: • risc-v
• optimization
• code generation
• instruction scheduling
discussion_id_link: —
bugzilla_pr: —
url: https://github.com/gcc-mirror/gcc/commit/5de59c6d8267ddfefec34317a67fa96b4f0900e2
date: 2026-04-26T00:00:00.000Z

GCC’s RISC-V backend now optimizes equality comparisons where the result of a logical AND operation is compared against zero. By right-shifting trailing zeros from constant, GCC can generate more efficient code sequences. This optimization reduces data dependencies and instruction count, especially when one operand of the AND requires synthesis, leading to performance gains and code density improvements.