MoonVeil-Docs/content/docs/options/flatten-control-flow.md

weight	title	description	icon	date	lastmod
100	Flatten control flow	Control flow flattener	article	2025-05-01T18:47:58-05:00	2025-05-01T18:47:58-05:00

This option enables Control Flow Flattening (CFF), restructuring control flow and statements into a dispatch-like state machine. The flattener prioritizes correctness; if flattening a block could cause side effects, it either skips that block or only partially flattens it.

The control flow flattener supports the following branching syntaxes:

• if statements
• while and repeat loops
• numeric for loops
• break and continue statements
• for-in loops and even support for Luau's generalized iteration

The following child options are available:

• Expression Decomposition: Breaks apart expressions into CFF blocks and temporaries, can kill performance.
• Wrap CFF blocks: Will move compatible CFF blocks into their own closure in a lookup table. Can speed up larger flattening targets.
• Hoist locals: Will move local storage into a lookup table. Useful to cut down on the number of used locals.