Function fabric_micro_listing 

pub fn fabric_micro_listing(
    p: &SpatialProgram,
    target: &SpatialTarget,
) -> Option<Vec<(Site, Engine, Vec<String>)>>

Each engine’s micro-program as the twin and the printer walk it: one line per state — the op, and a fixed op’s cycles; a tile walk’s run, and an accumulator walk’s region columns and run. None where the fabric does not lower p.