def cr_okb

bend-collections-laws-crypto@1.0.0.0 · proofs/crypto/curve25519/fold.bend:118

import Base
import bend-collections-laws-crypto@1.0.0.0/src/crypto/curve25519/field.bend as F
import bend-collections-laws-crypto@1.0.0.0/proofs/lib/nat.bend as N
import bend-collections-laws-crypto@1.0.0.0/proofs/lib/word.bend as WD
import bend-collections-laws-crypto@1.0.0.0/proofs/crypto/curve25519/limbs.bend as LM

118# the carry of a 32-limb input: its limbs, value and carry out
119def cr_okb(+one: Nat, +h1: {one == 1n : Nat}, +xs: List<&2, U32>, +hx: {LM.okb(32n, xs, WD.sc(28n, one)) == True{} : Bool}) -> {LM.okb(32n, LM.cl(F.carry(xs, 0)), 255n) == True{} : Bool}:
120  LM.carry_ok(one, h1, 32n, xs, 0, hx, N.zero_le(WD.sc(21n, one)))