Section StrongRelaxedInjections.

Lemma inject_hi_low_compose:
forall (j12 j23 : meminj) (x1 x2 x3 : block * Z * Z),
inject_hi_low j12 x1 x2 ->
inject_hi_low j23 x2 x3 -> inject_hi_low (compose_meminj j12 j23) x1 x3.