fact: Definition ww_mul_c := double_mul_c (fun xh xl yh yl hh ll=> match ww_add_c (w_mul_c xh yl) (w_mul_c xl yh) with | C0 cc => (w_0, cc) | C1 cc => (w_1, cc) end).
imports: ZArith Lia BigNumPrelude DoubleType DoubleBase