Function synthesized_needs 

pub fn synthesized_needs<S: AsRef<str>>(
    syn: &str,
    members: &[S],
    packing: &Packing,
) -> Result<Needs, String>

What the instances members need placed together as Quartus synthesized them, from the synthesis report syn: the entity table’s ALUTs, registers and DSP blocks of each member’s whole subtree summed, those ALUTs and registers in ALMs at packing packed as one (the fitter packs one member’s registers beside another’s LUTs), and the M20K blocks the fitter gives every memory under any of them (Ram::m20k). The member the entity table does not name, when one is missing.