Definition QBytes (l:list QuadByte) (v:val) : mpred :=
data_at Tsh (Tarray tuchar (4*Zlength l) noattr) (QuadChunks2ValList l) v.

Lemma QBytes16 s: SByte s = QBytes (flatten16 s).
Definition QuadWordRep (q:QuadWord):list val :=
match q with (q0, q1, q2, q3) => map Vint [q0;q1;q2;q3] end.