Landing: b392aaee7328

← All landings

Project / Subsystem

gcc / ifcvt

Date

2026-09-06

Author

Kyrylo Tkachov

Commit

b392aaee73282c29d14507e4ee58ef048b34b783

Source

github

Perf win

Breaking

View on GitHub →

All attributes

project: gcc
subsystem: ifcvt
patch_id: —
commit_hash: b392aaee73282c29d14507e4ee58ef048b34b783
source_type: github
headline: ifcvt: Clarify the limit imposed by MAX_CONDITIONAL_EXECUTE.
tldr: Adds a comment to MAX_CONDITIONAL_EXECUTE explaining its role in both conditional execution and speculative instruction limits.
author: Kyrylo Tkachov
outcome: committed
performance_win: false
breaking_change: false
series_id: —
series_parts: []
tags: • documentation
• optimization
discussion_id_link: —
bugzilla_pr: —
url: https://github.com/gcc-mirror/gcc/commit/b392aaee73282c29d14507e4ee58ef048b34b783
date: 2026-09-06T00:00:00.000Z

This commit updates a comment for MAX_CONDITIONAL_EXECUTE in the GCC ifcvt pass to clarify its usage. While the name suggests a limit on conditional execution, it also governs the number of instructions that branchless paths can speculate. The comment now explains that this limit is tested in noce_process_if_block and check_cond_move_block, and notes that the default configuration implies an unpredictable branch cost. This is a documentation-only change.