def cr.vm.f64
import bend-osdev-crypto@0.1.0.0/vmac.bend as Vmacimport Base
259# x below 2^128, folded: hi 2^64 + lo = hi 257 + lo (mod p64)
260def cr.vm.f64(x: CrU128) -> CrU128:
261 match x:
262 case CrU128{h, +l}:
263 cr.vm.add(cr.vm.mul(h, cr.vm.w(257)), cr.vm.u(l))