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Add lean source and binary files (part 59)
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import Mathlib.Data.List.Induction
import OAI.Computability.BinPacking.Computation.MachineUnaryEqualityBit
namespace OAI
namespace BinPackingCompleteness.BinaryNameMachine
open Turing
open BinPackingGames.Foundations.Complexity
open MachineComposition
open BinPackingGames.Reduction.MachineTransfer
def frame : List Bool → List Bool
| [] => [false]
| bit :: bits => true :: bit :: frame bits
def finalDigit : List Bool → Option Bool → Option Bool
| [], previous => previous
| bit :: bits, _ => finalDigit bits (some bit)
def canonical (bits : List Bool) : Bool := (finalDigit bits none).getD true
structure Result where
accepted : Bool
remaining : List Bool
reversedPayload : List Bool
deriving DecidableEq
def scanSpec : List Bool → List Bool → Option Bool → Result
| [], acc, _ => ⟨false, [], acc⟩
| false :: rest, acc, last => ⟨last.getD true, rest, acc⟩
| [true], acc, _ => ⟨false, [], acc⟩
| true :: bit :: rest, acc, _ => scanSpec rest (bit :: acc) (some bit)
def steps : List Bool → Nat
| true :: _ :: rest => steps rest + 1
| _ => 1
theorem steps_le (input : List Bool) : steps input ≤ input.length + 1 := by
induction input using List.twoStepInduction with
| nil => simp [steps]
| singleton bit => cases bit <;> simp [steps]
| cons_cons flag bit rest ih _ =>
cases flag <;> simp only [steps, List.length_cons]
· omega
· omega
@[simp] theorem frame_length (bits : List Bool) :
(frame bits).length = 2 * bits.length + 1 := by
induction bits with
| nil => simp [frame]
| cons bit bits ih => simp only [frame, List.length_cons, ih]; omega
theorem scanSpec_frame (bits suffix acc : List Bool) (last : Option Bool) :
scanSpec (frame bits ++ suffix) acc last =
⟨(finalDigit bits last).getD true, suffix, bits.reverse ++ acc⟩ := by
induction bits generalizing acc last with
| nil => simp [frame, scanSpec, finalDigit]
| cons bit bits ih =>
simpa [frame, scanSpec, finalDigit, List.reverse_cons, List.append_assoc] using
ih (bit :: acc) (some bit)
@[simp] theorem steps_frame (bits suffix : List Bool) :
steps (frame bits ++ suffix) = bits.length + 1 := by
induction bits with
| nil => simp [frame, steps]
| cons bit bits ih => simp [frame, steps, ih]
section Program
variable {K Λ A : Type} [DecidableEq K]
abbrev Alphabet (_ : K) := Bool
abbrev State (A : Type) := A × Option Bool × Option Bool
def clean (ambient : A) : State A := (ambient, none, none)
def exitAt (exit : Option Λ) : TM2.Stmt (Alphabet (K := K)) Λ (State A) :=
match exit with
| none => .halt
| some label => .goto fun _ => label
def finish (exit : Option Λ) : TM2.Stmt (Alphabet (K := K)) Λ (State A) :=
.load (fun state => clean state.1) (exitAt exit)
def scan (source destination : K) (again : Λ) (accepted rejected : Option Λ) :
TM2.Stmt (Alphabet (K := K)) Λ (State A) :=
.pop source (fun state head => (state.1, state.2.1, head))
(.branch (fun state => state.2.2.isNone)
(finish rejected)
(.branch (fun state => state.2.2.getD false)
(.pop source (fun state head => (state.1, state.2.1, head))
(.branch (fun state => state.2.2.isSome)
(.push destination (fun state => state.2.2.getD false)
(.load (fun state => (state.1, state.2.2, none))
(.goto fun _ => again)))
(finish rejected)))
(.branch (fun state => state.2.1.getD true)
(finish accepted) (finish rejected))))
@[simp] theorem stepAux_finish (exit : Option Λ) (state : State A)
(base : K → List Bool) :
TM2.stepAux (finish exit) state base = ⟨exit, clean state.1, base⟩ := by
cases exit <;> rfl
private theorem update_source (source destination : K) (distinct : source ≠ destination)
(base : K → List Bool) (input output replacement : List Bool) :
Function.update (tapesAt source destination base input output) source replacement =
tapesAt source destination base replacement output := by
funext k
by_cases hs : k = source
· subst k; simp [tapesAt, distinct]
· by_cases hd : k = destination
· subst k; simp [tapesAt, Ne.symm distinct]
· simp [tapesAt, hs, hd]
private theorem update_destination (source destination : K)
(base : K → List Bool) (input output replacement : List Bool) :
Function.update (tapesAt source destination base input output) destination replacement =
tapesAt source destination base input replacement := by
simp [tapesAt]
variable (source destination : K) (distinct : source ≠ destination)
variable (again : Λ) (accepted rejected : Option Λ)
variable (program : Λ → TM2.Stmt (Alphabet (K := K)) Λ (State A))
variable (atScan : program again = scan source destination again accepted rejected)
variable (base : K → List Bool) (ambient : A)
include distinct atScan
theorem step_empty (output : List Bool) (last register : Option Bool) :
TM2.step program
⟨some again, (ambient, last, register), tapesAt source destination base [] output⟩ =
some ⟨rejected, clean ambient, tapesAt source destination base [] output⟩ := by
change some (TM2.stepAux (program again) _ _) = _
rw [atScan]
simp [scan, TM2.stepAux, distinct, update_source]
theorem step_end (rest output : List Bool) (last register : Option Bool) :
TM2.step program
⟨some again, (ambient, last, register),
tapesAt source destination base (false :: rest) output⟩ =
some ⟨if last.getD true then accepted else rejected, clean ambient,
tapesAt source destination base rest output⟩ := by
change some (TM2.stepAux (program again) _ _) = _
rw [atScan]
cases h : last.getD true <;>
simp [scan, TM2.stepAux, distinct, update_source, h]
theorem step_truncated (output : List Bool) (last register : Option Bool) :
TM2.step program
⟨some again, (ambient, last, register), tapesAt source destination base [true] output⟩ =
some ⟨rejected, clean ambient, tapesAt source destination base [] output⟩ := by
change some (TM2.stepAux (program again) _ _) = _
rw [atScan]
simp [scan, TM2.stepAux, distinct, update_source]
theorem step_digit (bit : Bool) (rest output : List Bool) (last register : Option Bool) :
TM2.step program
⟨some again, (ambient, last, register),
tapesAt source destination base (true :: bit :: rest) output⟩ =
some ⟨some again, (ambient, some bit, none),
tapesAt source destination base rest (bit :: output)⟩ := by
change some (TM2.stepAux (program again) _ _) = _
rw [atScan]
simp [scan, TM2.stepAux, distinct, update_source, update_destination]
theorem scanTrace (input output : List Bool) (last register : Option Bool) :
(advance (TM2.step program))^[steps input]
(some ⟨some again, (ambient, last, register),
tapesAt source destination base input output⟩) =
some ⟨if (scanSpec input output last).accepted then accepted else rejected,
clean ambient, tapesAt source destination base
(scanSpec input output last).remaining (scanSpec input output last).reversedPayload⟩ := by
induction input using List.twoStepInduction generalizing output last register with
| nil =>
simpa only [steps, scanSpec, Bool.false_eq_true, ite_false,
Function.iterate_one, advance_some] using
step_empty source destination distinct again accepted rejected program atScan base ambient
output last register
| singleton flag =>
cases flag
· have h := step_end source destination distinct again accepted rejected program atScan
base ambient [] output last register
cases hlast : last.getD true <;>
simpa [steps, scanSpec, hlast] using h
· simpa only [steps, scanSpec, Bool.false_eq_true, ite_false,
Function.iterate_one, advance_some] using
step_truncated source destination distinct again accepted rejected program atScan base ambient
output last register
| cons_cons flag bit rest ih _ =>
cases flag
· have h := step_end source destination distinct again accepted rejected program atScan
base ambient (bit :: rest) output last register
cases hlast : last.getD true <;>
simpa [steps, scanSpec, hlast] using h
· rw [steps, Function.iterate_succ_apply]
simp only [advance_some]
rw [step_digit source destination distinct again accepted rejected program atScan]
exact ih (bit :: output) (some bit) none
def scanInTime (input output : List Bool) (last register : Option Bool) :
StateTransition.EvalsToInTime (TM2.step program)
⟨some again, (ambient, last, register), tapesAt source destination base input output⟩
(some ⟨if (scanSpec input output last).accepted then accepted else rejected,
clean ambient, tapesAt source destination base
(scanSpec input output last).remaining (scanSpec input output last).reversedPayload⟩)
(input.length + 1) where
steps := steps input
evals_in_steps := scanTrace source destination distinct again accepted rejected program atScan
base ambient input output last register
steps_le_m := steps_le input
theorem framedTrace (bits suffix output : List Bool) (register : Option Bool) :
(advance (TM2.step program))^[bits.length + 1]
(some ⟨some again, (ambient, none, register),
tapesAt source destination base (frame bits ++ suffix) output⟩) =
some ⟨if canonical bits then accepted else rejected, clean ambient,
tapesAt source destination base suffix (bits.reverse ++ output)⟩ := by
have h := scanTrace source destination distinct again accepted rejected program atScan
base ambient (frame bits ++ suffix) output none register
cases hlast : (finalDigit bits none).getD true <;>
simpa [steps_frame, scanSpec_frame, canonical, hlast] using h
end Program
def machine : FinTM2 where
K := Bool
k₀ := false
k₁ := true
Γ _ := Bool
Λ := Fin 3
main := 0
σ := State Unit
initialState := clean ()
m label := if label = 0 then scan false true 0 (some 1) (some 2) else .halt
theorem machine_finiteAlphabet (k : machine.K) : Finite (machine.Γ k) := by
change Finite Bool
infer_instance
def machineInTime (input output : List Bool) :
StateTransition.EvalsToInTime machine.step
⟨some (0 : Fin 3), clean (), tapesAt false true (fun _ : Bool => []) input output⟩
(some ⟨if (scanSpec input output none).accepted then some (1 : Fin 3) else some (2 : Fin 3),
clean (), tapesAt false true (fun _ : Bool => [])
(scanSpec input output none).remaining (scanSpec input output none).reversedPayload⟩)
(input.length + 1) :=
scanInTime false true (by decide) (0 : Fin 3) (some 1) (some 2) machine.m
(by simp [machine]) (fun _ : Bool => []) () input output none none
end BinPackingCompleteness.BinaryNameMachine
namespace BinPackingCompleteness.BinaryNameCompare
open Turing
open BinPackingGames.Foundations.Complexity
open MachineComposition
variable {K Λ A : Type} [DecidableEq K]
abbrev Alphabet (_ : K) := Bool
abbrev State (A : Type) := (A × Bool × Option Bool) × Option Bool
def clean (ambient : A) : State A := ((ambient, false, none), none)
def scanStateEquiv (A : Type) : BinaryNameMachine.State (A × Bool) ≃ State A where
toFun s := ((s.1.1, s.1.2, s.2.1), s.2.2)
invFun s := ((s.1.1, s.1.2.1), s.1.2.2, s.2)
left_inv := by rintro ⟨⟨a, b⟩, c, d⟩; rfl
right_inv := by rintro ⟨⟨a, b, c⟩, d⟩; rfl
def compareStateEquiv (A : Type) : MachineCompare.State A ≃ State A where
toFun s := ((s.1, s.2.1, s.2.2.1), s.2.2.2)
invFun s := (s.1.1, s.1.2.1, s.1.2.2, s.2)
left_inv := by rintro ⟨a, b, c, d⟩; rfl
right_inv := by rintro ⟨⟨a, b, c⟩, d⟩; rfl
inductive Label
| scan | copyOut | copyBack | compare
deriving DecidableEq
protected abbrev Label.enumList : List Label := [.scan, .copyOut, .copyBack, .compare]
protected theorem Label.enumList_getElem?_ctorIdx_eq (x : Label) :
Label.enumList[x.ctorIdx]? = some x := by
cases x <;> rfl
protected theorem Label.enumList_nodup : Label.enumList.Nodup := by decide
instance : Fintype Label where
elems := ⟨Label.enumList, Label.enumList_nodup⟩
complete x := by cases x <;> decide
def instruction (tape : Fin 5 → K) (labels : Label → Λ)
(equalExit differentExit malformedExit : Option Λ) :
Label → TM2.Stmt (Alphabet (K := K)) Λ (State A)
| .scan => MachineStateEquiv.statement (scanStateEquiv A)
(BinaryNameMachine.scan (tape 0) (tape 2) (labels .scan)
(some (labels .copyOut)) malformedExit)
| .copyOut => BinPackingGames.Reduction.MachineTransfer.loopAt (tape 1) (tape 4) id false
(labels .copyOut) (some (labels .copyBack))
| .copyBack => MachineCopy.forkLoop (tape 4) (tape 1) (tape 3) false
(labels .copyBack) (some (labels .compare))
| .compare => MachineStateEquiv.statement (compareStateEquiv A)
(MachineCompare.loop (tape 2) (tape 3) (labels .compare) equalExit differentExit)
def steps (payloadLength keyLength : Nat) : Nat :=
(payloadLength + 1) + 2 * (keyLength + 1) + (max payloadLength keyLength + 1)
theorem steps_le (payloadLength keyLength : Nat) :
steps payloadLength keyLength ≤ 2 * payloadLength + 3 * keyLength + 4 := by
unfold steps
omega
private theorem joinTrace {X : Type*} {f : X → X} {a b c : X} {n m : Nat}
(first : f^[n] a = b) (second : f^[m] b = c) : f^[n + m] a = c := by
rw [Nat.add_comm, Function.iterate_add_apply, first, second]
theorem compareTrace (tape : Fin 5 → K) (distinct : Function.Injective tape)
(labels : Label → Λ) (equalExit differentExit malformedExit : Option Λ)
(program : Λ → TM2.Stmt (Alphabet (K := K)) Λ (State A))
(atLabels : ∀ l, program (labels l) =
instruction tape labels equalExit differentExit malformedExit l)
(base : K → List Bool) (bits suffix key : List Bool)
(canonical : BinaryNameMachine.canonical bits = true)
(sourceWord : base (tape 0) = BinaryNameMachine.frame bits ++ suffix)
(keyWord : base (tape 1) = key)
(candidateEmpty : base (tape 2) = []) (copyEmpty : base (tape 3) = [])
(scratchEmpty : base (tape 4) = []) (ambient : A) :
(advance (TM2.step program))^[steps bits.length key.length]
(some ⟨some (labels .scan), clean ambient, base⟩) =
some ⟨if bits.reverse = key then equalExit else differentExit,
clean ambient, Function.update base (tape 0) suffix⟩ := by
have hd (i j : Fin 5) (hne : i ≠ j) : tape i ≠ tape j := fun h => hne (distinct h)
let finalBase := Function.update base (tape 0) suffix
let afterScan := Function.update finalBase (tape 2) bits.reverse
let afterCopy := Function.update afterScan (tape 3) key
have scanRun : (advance (TM2.step program))^[bits.length + 1]
(some ⟨some (labels .scan), clean ambient, base⟩) =
some ⟨some (labels .copyOut), clean ambient, afterScan⟩ := by
let back := MachineStateEquiv.program (scanStateEquiv A).symm program
have atScan : back (labels .scan) =
BinaryNameMachine.scan (tape 0) (tape 2) (labels .scan)
(some (labels .copyOut)) malformedExit := by
change MachineStateEquiv.statement (scanStateEquiv A).symm
(program (labels .scan)) = _
rw [atLabels .scan]
exact MachineStateEquiv.statement_symm_statement (scanStateEquiv A) _
have backForward : MachineStateEquiv.program (scanStateEquiv A) back = program := by
funext l
change MachineStateEquiv.statement (scanStateEquiv A)
(MachineStateEquiv.statement (scanStateEquiv A).symm (program l)) = _
simpa only [Equiv.symm_symm] using
MachineStateEquiv.statement_symm_statement (scanStateEquiv A).symm (program l)
have initialTapes : BinPackingGames.Reduction.MachineTransfer.tapesAt (tape 0) (tape 2)
base (BinaryNameMachine.frame bits ++ suffix) [] = base := by
rw [← sourceWord, ← candidateEmpty]
exact BinPackingGames.Reduction.MachineTransfer.tapesAt_self _ _ _
have native := BinaryNameMachine.framedTrace (tape 0) (tape 2) (hd 0 2 (by decide))
(labels .scan) (some (labels .copyOut)) malformedExit back atScan base (ambient, false)
bits suffix [] none
simp only [canonical, ↓reduceIte, initialTapes, List.append_nil] at native
have transported := MachineStateEquiv.trace (scanStateEquiv A) back _ _ _ native
rw [backForward] at transported
simpa only [MachineStateEquiv.configuration, scanStateEquiv, Equiv.coe_fn_mk, BinaryNameMachine.clean,
clean, afterScan, finalBase, BinPackingGames.Reduction.MachineTransfer.tapesAt] using transported
have afterScanKey : afterScan (tape 1) = key := by
simpa [afterScan, finalBase, hd 1 2 (by decide), hd 1 0 (by decide)] using keyWord
have afterScanCopy : afterScan (tape 3) = [] := by
simpa [afterScan, finalBase, hd 3 2 (by decide), hd 3 0 (by decide)] using copyEmpty
have afterScanScratch : afterScan (tape 4) = [] := by
simpa [afterScan, finalBase, hd 4 2 (by decide), hd 4 0 (by decide)] using scratchEmpty
have copyRun : (advance (TM2.step program))^[2 * (key.length + 1)]
(some ⟨some (labels .copyOut), clean ambient, afterScan⟩) =
some ⟨some (labels .compare), clean ambient, afterCopy⟩ := by
have h := MachineCopy.copyTrace (tape 1) (tape 3) (tape 4)
(hd 1 3 (by decide)) (hd 1 4 (by decide)) (hd 3 4 (by decide)) false
(labels .copyOut) (labels .copyBack) (some (labels .compare)) program
(atLabels .copyOut) (atLabels .copyBack) afterScan afterScanScratch
(ambient, false, none) none
simpa only [afterScanKey, afterScanCopy, List.append_nil, clean, afterCopy] using h
have candidateWord : afterCopy (tape 2) = bits.reverse := by
simp [afterCopy, afterScan, hd 2 3 (by decide)]
have copiedWord : afterCopy (tape 3) = key := by simp [afterCopy]
have restored : BinPackingGames.Reduction.MachineTransfer.tapesAt (tape 2) (tape 3)
afterCopy [] [] = finalBase := by
funext k
by_cases hc : k = tape 2
· subst k
simp [BinPackingGames.Reduction.MachineTransfer.tapesAt, afterCopy, afterScan, finalBase,
hd 2 3 (by decide), hd 2 0 (by decide), candidateEmpty]
· by_cases hk : k = tape 3
· subst k
simp [BinPackingGames.Reduction.MachineTransfer.tapesAt, afterCopy, afterScan, finalBase,
hd 3 0 (by decide), copyEmpty]
· simp [BinPackingGames.Reduction.MachineTransfer.tapesAt, afterCopy, afterScan, hc, hk]
have comparisonRun : (advance (TM2.step program))^[max bits.length key.length + 1]
(some ⟨some (labels .compare), clean ambient, afterCopy⟩) =
some ⟨if bits.reverse = key then equalExit else differentExit,
clean ambient, finalBase⟩ := by
let back := MachineStateEquiv.program (compareStateEquiv A).symm program
have atCompare : back (labels .compare) =
MachineCompare.loop (tape 2) (tape 3) (labels .compare) equalExit differentExit := by
change MachineStateEquiv.statement (compareStateEquiv A).symm
(program (labels .compare)) = _
rw [atLabels .compare]
exact MachineStateEquiv.statement_symm_statement (compareStateEquiv A) _
have backForward : MachineStateEquiv.program (compareStateEquiv A) back = program := by
funext l
change MachineStateEquiv.statement (compareStateEquiv A)
(MachineStateEquiv.statement (compareStateEquiv A).symm (program l)) = _
simpa only [Equiv.symm_symm] using
MachineStateEquiv.statement_symm_statement (compareStateEquiv A).symm (program l)
have native := MachineCompare.compareTrace_fromTapes (tape 2) (tape 3)
(hd 2 3 (by decide)) (labels .compare) equalExit differentExit back atCompare afterCopy
ambient none none
rw [candidateWord, copiedWord, restored, List.length_reverse] at native
have transported := MachineStateEquiv.trace (compareStateEquiv A) back _ _ _ native
rw [backForward] at transported
simpa only [MachineStateEquiv.configuration, compareStateEquiv, Equiv.coe_fn_mk, clean] using transported
exact joinTrace (joinTrace scanRun copyRun) comparisonRun
def compareInTime (tape : Fin 5 → K) (distinct : Function.Injective tape)
(labels : Label → Λ) (equalExit differentExit malformedExit : Option Λ)
(program : Λ → TM2.Stmt (Alphabet (K := K)) Λ (State A))
(atLabels : ∀ l, program (labels l) =
instruction tape labels equalExit differentExit malformedExit l)
(base : K → List Bool) (bits suffix key : List Bool)
(canonical : BinaryNameMachine.canonical bits = true)
(sourceWord : base (tape 0) = BinaryNameMachine.frame bits ++ suffix)
(keyWord : base (tape 1) = key)
(candidateEmpty : base (tape 2) = []) (copyEmpty : base (tape 3) = [])
(scratchEmpty : base (tape 4) = []) (ambient : A) :
StateTransition.EvalsToInTime (TM2.step program)
⟨some (labels .scan), clean ambient, base⟩
(some ⟨if bits.reverse = key then equalExit else differentExit,
clean ambient, Function.update base (tape 0) suffix⟩)
(2 * bits.length + 3 * key.length + 4) where
steps := steps bits.length key.length
evals_in_steps := compareTrace tape distinct labels equalExit differentExit malformedExit
program atLabels base bits suffix key canonical sourceWord keyWord
candidateEmpty copyEmpty scratchEmpty ambient
steps_le_m := steps_le bits.length key.length
def machine : FinTM2 where
K := Fin 5
k₀ := 0
k₁ := 1
Γ _ := Bool
Λ := Label ⊕ Fin 3
main := .inl .scan
σ := State Unit
initialState := clean ()
m label := match label with
| .inl l => instruction id Sum.inl (some (.inr 0)) (some (.inr 1)) (some (.inr 2)) l
| .inr _ => .halt
theorem machine_finiteAlphabet (k : machine.K) : Finite (machine.Γ k) := by
change Finite Bool
infer_instance
end BinPackingCompleteness.BinaryNameCompare
end OAI