Function chip_record 

pub fn chip_record(p: &SpatialProgram, target: &SpatialTarget) -> Option<Value>

What a host needs of one chip’s program of a program split over chips, as its ledger states it: the twin’s count at each halt and at the end (fabric_cycle_segments), each link — the section it follows, whether the fabric halts there, and each tensor it sends and receives with its id and every element’s host word, row-major — the words of the step’s inputs (tok, pos) the chip holds, and of its result (next) if it holds it. None where the fabric does not lower p.