Landing: 3526c3b792cc

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Project / Subsystem

gcc / vrp

Date

2026-10-03

Author

Aldy Hernandez

Commit

3526c3b792cc55d00a0585639baa5a6810899df1

Source

github

Perf win

Breaking

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All attributes

project: gcc
subsystem: vrp
patch_id: —
commit_hash: 3526c3b792cc55d00a0585639baa5a6810899df1
source_type: github
headline: VRP: Fold LE or GE tests between names into equality checks.
tldr: VRP pass now folds LE/GE comparisons between two variables into equality when possible.
author: Aldy Hernandez
outcome: committed
performance_win: false
breaking_change: false
series_id: —
series_parts: []
tags: • optimization
• compiler
discussion_id_link: —
bugzilla_pr: —
url: https://github.com/gcc-mirror/gcc/commit/3526c3b792cc55d00a0585639baa5a6810899df1
date: 2026-10-03T00:00:00.000Z

The Value Range Propagation (VRP) pass can now fold less-than-or-equal (LE) or greater-than-or-equal (GE) tests between two variables into an equality test. This occurs when the relation oracle implies that if x <= y, then x must equal y, or similarly if x >= y. This change improves intermediate representation simplification by moving this logic from DOM to the simplifier.