cse()

Syntax

function cse(m: ModuleDecl): ModuleDecl

Parameters

m ModuleDecl

The module to optimize.

Return value

ModuleDecl

A new module with the rewritten functions; m is not modified.

Description

For every function in m, finds each compound expression that appears two or more times and reads only the function’s inputs (parameters, constants and bindings; never a local variable or a name the function writes to), binds it once to a let, and replaces every occurrence with a reference to that let. The let is placed at the top of the innermost block that contains all of the occurrences, just before the first statement that uses it, so a value used only inside one branch is computed only when that branch runs. A let is never placed inside a loop body. Only the outermost repeated expression is hoisted: two occurrences of sqrt(dot(p, p)) become one temporary holding the whole value. A function whose body contains raw shader text is returned unchanged.

Source

src/core/passes/opt/cse.ts, line 255, at commit 26de7be8