def round_lt1

bend-collections-laws-crypto@1.0.0.0 · proofs/crypto/secp256k1/reduce.bend:292

import Base
import bend-collections-laws-crypto@1.0.0.0/spec/lib/common.bend as C
import bend-collections-laws-crypto@1.0.0.0/spec/crypto/secp256k1/field.bend as FS
import bend-collections-laws-crypto@1.0.0.0/src/crypto/secp256k1/limbs.bend as L
import bend-collections-laws-crypto@1.0.0.0/proofs/crypto/secp256k1/limbs.bend as LV

292# below 2^256 H after a round, from below 2^256 H' before (H = 1 + H' c)
293def round_lt1(+one: Nat, +h1: {one == 1n : Nat}, +c: List<&2, Nat>, +xs: List<&2, Nat>, +hh: Nat, +hlo: {FS.limbs16(one, 16n, L.take(16n, xs)) == True{} : Bool}, +hx: {Nat.is_lt(LV.ev(xs), Nat.mul(hh, C.shift(256n, one))) == True{} : Bool}) -> {Nat.is_lt(LV.ev(L.carry(32n, L.fold(c, xs), 0n)), Nat.add(C.shift(256n, one), Nat.mul(hh, LV.ev(c)))) == True{} : Bool}:
294  %Equal.sym(Nat, LV.ev(L.carry(32n, L.fold(c, xs), 0n)), LV.ev(L.fold(c, xs)), round_v(c, xs)) : {Nat.is_lt(_, Nat.add(C.shift(256n, one), Nat.mul(hh, LV.ev(c)))) == True{} : Bool}
295  fold_lt1(one, h1, c, xs, hh, hlo, hx)