U64.add_value: def of bend-collections-laws-math@1.0.0.0
Import: import bend-collections-laws-math@1.0.0.0/proofs/math/u64/u64.bend as U64
Lines 202-220 of bend-collections-laws-math@1.0.0.0/proofs/math/u64/u64.bend: https://jend.leeeet.dev/read.txt?path=bend-collections-laws-math@1.0.0.0/proofs/math/u64/u64.bend&start_line=202&end_line=220

import Base
import bend-collections-laws-math@1.0.0.0/src/math/u64.bend as U
import bend-collections-laws-math@1.0.0.0/proofs/lib/lemmas/src/wide.bend as W
import bend-collections-laws-math@1.0.0.0/proofs/lib/lemmas/spec/numeric.bend as S
import bend-collections-laws-math@1.0.0.0/proofs/lib/word.bend as WD
import bend-collections-laws-math@1.0.0.0/proofs/lib/u32div.bend as UD

# the sum loses exactly 2^64 times the high carries
def add_value(+a: U.U64, +b: U.U64) -> {Nat.add(val(U.add(a, b)), WD.sc(64n, add_over(a, b))) == Nat.add(val(a), val(b)) : Nat}:
  match a b:
    case U.U64{+alo, +ahi} U.U64{+blo, +bhi}:
      +lo = U32.add(alo, blo)
      +cb = U32.is_lt(lo, alo)
      +t = U32.add(ahi, bhi)
      +h = U32.add(t, U.carry(cb))
      +c0 = S.bit_value(carry32(alo, blo))
      +c1 = S.bit_value(carry32(ahi, bhi))
      +c2 = S.bit_value(carry32(t, U.carry(cb)))
      +f1 = add_cons(alo, blo)
      +f2 = add_cons(ahi, bhi)
      +f3 = Equal.trans(Nat, Nat.add(UD.v(h), WD.sc(32n, c2)), Nat.add(UD.v(t), UD.v(U.carry(cb))), Nat.add(UD.v(t), c0), add_cons(t, U.carry(cb)),
        Equal.cong(Nat, Nat, z => Nat.add(UD.v(t), z), UD.v(U.carry(cb)), c0, Equal.trans(Nat, UD.v(U.carry(cb)), S.bit_value(cb), c0, carry_v(cb), Equal.cong(Bool, Nat, S.bit_value, cb, carry32(alo, blo), add_lt(alo, blo)))))
      %Equal.sym(Nat, S.unsigned(64n, W.pack(lo, h)), Nat.add(UD.v(lo), WD.sc(32n, UD.v(h))), val_pack(lo, h)) : {Nat.add(_, WD.sc(64n, Nat.add(c1, c2))) == Nat.add(S.unsigned(64n, W.pack(alo, ahi)), S.unsigned(64n, W.pack(blo, bhi))) : Nat}
      %Equal.sym(Nat, S.unsigned(64n, W.pack(alo, ahi)), Nat.add(UD.v(alo), WD.sc(32n, UD.v(ahi))), val_pack(alo, ahi)) : {Nat.add(Nat.add(UD.v(lo), WD.sc(32n, UD.v(h))), WD.sc(64n, Nat.add(c1, c2))) == Nat.add(_, S.unsigned(64n, W.pack(blo, bhi))) : Nat}
      %Equal.sym(Nat, S.unsigned(64n, W.pack(blo, bhi)), Nat.add(UD.v(blo), WD.sc(32n, UD.v(bhi))), val_pack(blo, bhi)) : {Nat.add(Nat.add(UD.v(lo), WD.sc(32n, UD.v(h))), WD.sc(64n, Nat.add(c1, c2))) == Nat.add(Nat.add(UD.v(alo), WD.sc(32n, UD.v(ahi))), _) : Nat}
      WD.add_alg(32n, UD.v(lo), UD.v(h), UD.v(t), c0, c1, c2, UD.v(alo), UD.v(ahi), UD.v(blo), UD.v(bhi), f1, f2, f3)

Uses (24):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.cong
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.sym
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.trans
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.add
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.add
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.is_lt
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/lemmas/spec/numeric.bend&name=bit_value
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/lemmas/spec/numeric.bend&name=unsigned
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/lemmas/src/wide.bend&name=pack
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/u32div.bend&name=v
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/word.bend&name=add_alg
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/word.bend&name=sc
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/math/u64/u64.bend&name=add_cons
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/math/u64/u64.bend&name=add_lt
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/math/u64/u64.bend&name=add_over
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/math/u64/u64.bend&name=carry32
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/math/u64/u64.bend&name=carry_v
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/math/u64/u64.bend&name=val
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/math/u64/u64.bend&name=val_pack
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/src/math/u64.bend&name=U64
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/src/math/u64.bend&name=add
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/src/math/u64.bend&name=carry