Function separate_phase_memory 

pub fn separate_phase_memory(p: &mut SpatialProgram) -> u32

★ A PHASE’S SECTIONS RUN AT ONCE, SO THEY DO NOT SHARE A BYTE. Each section lays its buffers out over its sites’ local memory from the same base; sections a barrier separates reuse those bytes, sections of one phase may not. A section of a phase that shares a site with an earlier one of the phase has its buffers there moved past the earlier ones’ (per memory space) — sections on disjoint sites keep their layout. Returns the highest byte any site now uses, for the caller to hold against the site’s memory.