diff --git a/naga/src/proc/constant_evaluator.rs b/naga/src/proc/constant_evaluator.rs
index bc2adde5a73..ab75c5bf281 100644
--- a/naga/src/proc/constant_evaluator.rs
+++ b/naga/src/proc/constant_evaluator.rs
@@ -750,6 +750,11 @@ impl<'a> ConstantEvaluator<'a> {
             crate::MathFunction::Sqrt => {
                 component_wise_float!(self, span, [arg], |e| { e.sqrt().into() })
             }
+            crate::MathFunction::Step => {
+                component_wise_float!(self, span, [arg, arg1.unwrap()], |edge, x| {
+                    if edge <= x { 1.0 } else { 0.0 }.into()
+                })
+            }
             fun => Err(ConstantEvaluatorError::NotImplemented(format!(
                 "{fun:?} built-in function"
             ))),