def fast_find2_pair.go

lawful-bytes@0.1.1.0 · PROOF.bend:493

import Base
import lawful-bytes@0.1.1.0/defs.bend as D
import lawful-bytes@0.1.1.0/fast.bend as FA
import lawful-bytes@0.1.1.0/proof_core.bend as C
import lawful-bytes@0.1.1.0/proof_fast_find2.bend as FF2

493def fast_find2_pair.go(-b: D.Bytes, +from: U32, +to: U32, +c1: U32, +c2: U32, m_b: C.BMirror(b)) ->
494  {FA.find2(b, from, to, c1, c2) == (b, Pair.snd(D.Bytes, U32, FA.find2(b, from, to, c1, c2))) : D.Bytes & U32}:
495  (+l_b, m2_b) = m_b
496  (+t_b, +e_b) = m2_b
497  %e_b : {FA.find2(_, from, to, c1, c2) == (_, Pair.snd(D.Bytes, U32, FA.find2(_, from, to, c1, c2))) : D.Bytes & U32}
498  +r1 = FA.rep(c1)
499  +r2 = FA.rep(c2)
500  +MN = U32.min(FF2.FG2(FA.words(from, to), U32.is_zero(FF2.M02(t_b, from, r1, r2)), (from >> 2n : U32), FF2.M02(t_b, from, r1, r2), r1, r2, t_b), to)
501  %Equal.sym(D.Bytes & U32, FA.find2(C.BT(l_b, t_b), from, to, c1, c2), (C.BT(l_b, t_b), MN), FF2.fast2_eq(l_b, t_b, from, to, c1, c2)) :
502    {_ == (C.BT(l_b, t_b), Pair.snd(D.Bytes, U32, _)) : D.Bytes & U32}
503  {==}