Where can I find LobeRoughness and LobeEnergy function?

I’m trying to test custom BRDFs. I see that StandardShading models use LobeRoughness and LobeEnergy function
but I can’t find where they are. I’ve looked in to most of the built-in shader.ush files. Someone help please!
And does Default Lit material use StandardShading function or StandardShadingPerLight function?

These two parameters are related to spotlight. If it is directional light, LobeRoughness is Roughness, LobeEnergy = 1