Lean migration: typeclass-based parameter passing, as in the Agda original

The port had flattened Agda's instance arguments ({{flA}}, {{evaluator}},
{{latticeInterpretation}}, {{validEvaluator}}) into explicitly threaded
values (fhL, E, I, hE). Restore them as typeclasses:

- Spa.FiniteHeightLattice: now actually used — Fixedpoint takes the
  instance instead of a FixedHeight value; FiniteMap gets the missing
  instance (height = ks.length * height B), so varsFixedHeight /
  statesFixedHeight / signFixedHeight / constFixedHeight plumbing
  disappears (instance bottoms are defeq to the old ones)
- Spa.Analysis.Forward.Evaluation: StmtEvaluator/ExprEvaluator become
  classes; the Valid* Props become Prop-classes, as in Agda
- Spa.Analysis.Forward.Adapters: the expr→stmt adapter and its validity
  are instances (Agda: the ExprToStmtAdapter instances)
- LatticeInterpretation is a class; sign/const interpretations,
  evaluators and validity proofs are instances; use sites read like the
  Agda module applications: result SignLattice prog

Proof simplifications (same theorems, proofs factored):

- Spa.Lattice.AboveBelow.monotone₂_of_strict: any ⊥-strict/⊤-dominated
  operation on a flat lattice is monotone — replaces the four near-
  identical case bashes per analysis (postulates in Agda)
- Spa.Lattice.AboveBelow.interp_sup_of/interp_inf_of: the shared flat-
  lattice interpretation case analysis, making interpSign_sup/inf and
  interpConst_sup/inf one-liners

lake build green with zero warnings; lake exe spa output verified
byte-identical (diff) to the previous, Agda-verified output.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
This commit is contained in:
2026-06-09 23:32:38 -07:00
parent b26d6b5acd
commit b16f14fdfd
12 changed files with 338 additions and 407 deletions

View File

@@ -2,6 +2,12 @@
Port of `Analysis/Forward.agda` (`WithProg`, `WithStmtEvaluator`,
`WithValidInterpretation`).
As in Agda, the statement evaluator, the lattice interpretation and the
evaluator's validity proof are instance arguments (`{{evaluator}}`,
`{{latticeInterpretationˡ}}`, `{{validEvaluator}}`); `result` and
`analyze_correct` take `L` and `prog` explicitly, mirroring the Agda call
shape `WithProg.result L prog`.
Correspondence:
updateVariablesForState, -Monoʳ ↦ updateVariablesForState, _mono
updateAll, updateAll-Mono,
@@ -26,139 +32,136 @@ import Spa.Fixedpoint
namespace Spa
variable {L : Type} [Lattice L] [DecidableEq L] {prog : Program} {h : }
(fhL : FixedHeight L h) (E : StmtEvaluator L prog)
variable {L : Type} [Lattice L] {prog : Program} [E : StmtEvaluator L prog]
/-- Agda: `updateVariablesForState`. -/
def updateVariablesForState (s : prog.State) (sv : StateVariables L prog) :
VariableValues L prog :=
(prog.code s).foldl (fun vs bs => E.eval s bs vs) (variablesAt s sv)
omit [DecidableEq L] in
/-- Agda: `updateVariablesForState-Monoʳ`. -/
theorem updateVariablesForState_mono (s : prog.State) :
Monotone (updateVariablesForState E s) := fun _ _ hle =>
Monotone (updateVariablesForState (L := L) s) := fun _ _ hle =>
foldl_mono' (prog.code s) _ (fun bs => E.eval_mono s bs) (variablesAt_le hle s)
/-- Agda: `updateAll`. -/
def updateAll (sv : StateVariables L prog) : StateVariables L prog :=
FiniteMap.generalizedUpdate id (fun s sv => updateVariablesForState E s sv)
FiniteMap.generalizedUpdate id (fun s sv => updateVariablesForState s sv)
prog.states sv
omit [DecidableEq L] in
/-- Agda: `updateAll-Mono`. -/
theorem updateAll_mono : Monotone (updateAll E) :=
FiniteMap.generalizedUpdate_monotone monotone_id (updateVariablesForState_mono E)
theorem updateAll_mono : Monotone (updateAll (L := L) (prog := prog)) :=
FiniteMap.generalizedUpdate_monotone monotone_id updateVariablesForState_mono
omit [DecidableEq L] in
/-- Agda: `updateAll-k∈ks-≡`. -/
theorem updateAll_mem_eq {s : prog.State} {vs : VariableValues L prog}
{sv : StateVariables L prog} (hmem : (s, vs) updateAll E sv) :
vs = updateVariablesForState E s sv :=
{sv : StateVariables L prog} (hmem : (s, vs) updateAll sv) :
vs = updateVariablesForState s sv :=
FiniteMap.generalizedUpdate_mem_eq (prog.states_complete s) hmem
omit [DecidableEq L] in
/-- Agda: `variablesAt-updateAll`. -/
theorem variablesAt_updateAll (s : prog.State) (sv : StateVariables L prog) :
variablesAt s (updateAll E sv) = updateVariablesForState E s sv :=
updateAll_mem_eq E (variablesAt_mem s (updateAll E sv))
variablesAt s (updateAll sv) = updateVariablesForState s sv :=
updateAll_mem_eq (variablesAt_mem s (updateAll sv))
variable [FiniteHeightLattice L]
/-- Agda: `analyze`. -/
def analyze (sv : StateVariables L prog) : StateVariables L prog :=
updateAll E (joinAll fhL sv)
updateAll (joinAll sv)
omit [DecidableEq L] in
/-- Agda: `analyze-Mono`. -/
theorem analyze_mono : Monotone (analyze fhL E) := fun _ _ hle =>
updateAll_mono E (joinAll_mono fhL hle)
theorem analyze_mono : Monotone (analyze (L := L) (prog := prog)) := fun _ _ hle =>
updateAll_mono (joinAll_mono hle)
variable [DecidableEq L]
variable (L prog) in
/-- Agda: `result` (the least fixpoint of `analyze`). -/
def result : StateVariables L prog :=
Fixedpoint.aFix (statesFixedHeight L prog fhL) (analyze fhL E) (analyze_mono fhL E)
Fixedpoint.aFix analyze analyze_mono
variable (L prog) in
/-- Agda: `result≈analyze-result`. -/
theorem result_eq : result fhL E = analyze fhL E (result fhL E) :=
Fixedpoint.aFix_eq (statesFixedHeight L prog fhL) (analyze fhL E) (analyze_mono fhL E)
theorem result_eq : result L prog = analyze (result L prog) :=
Fixedpoint.aFix_eq analyze analyze_mono
/-- Agda: `joinForKey-initialState-⊥ᵛ`. -/
theorem joinForKey_initialState :
joinForKey prog.initialState (result L prog) = botV L prog := by
rw [joinForKey, prog.incoming_initialState_eq_nil]
rfl
/-! ### Semantic correctness (Agda: `WithValidInterpretation`) -/
variable {I : LatticeInterpretation L} {E}
variable (hE : IsValidStmtEvaluator E I)
include hE
variable [I : LatticeInterpretation L] [V : ValidStmtEvaluator L prog]
omit [DecidableEq L] in
omit [FiniteHeightLattice L] [DecidableEq L] in
/-- Agda: `eval-fold-valid`. -/
theorem eval_fold_valid {s : prog.State} {bss : List BasicStmt}
{vs : VariableValues L prog} {ρ₁ ρ₂ : Env}
(hbss : EvalBasicStmts ρ₁ bss ρ₂) (hvs : interpV I vs ρ₁) :
interpV I (bss.foldl (fun vs bs => E.eval s bs vs) vs) ρ₂ := by
(hbss : EvalBasicStmts ρ₁ bss ρ₂) (hvs : interpV vs ρ₁) :
interpV (bss.foldl (fun vs bs => E.eval s bs vs) vs) ρ₂ := by
induction hbss generalizing vs with
| nil => exact hvs
| cons hbs _ ih => exact ih (hE hbs hvs)
| cons hbs _ ih => exact ih (ValidStmtEvaluator.valid hbs hvs)
omit [DecidableEq L] in
omit [FiniteHeightLattice L] [DecidableEq L] in
/-- Agda: `updateVariablesForState-matches`. -/
theorem updateVariablesForState_matches {s : prog.State}
{sv : StateVariables L prog} {ρ₁ ρ₂ : Env}
(hbss : EvalBasicStmts ρ₁ (prog.code s) ρ₂)
(hvs : interpV I (variablesAt s sv) ρ₁) :
interpV I (updateVariablesForState E s sv) ρ₂ :=
eval_fold_valid hE hbss hvs
(hvs : interpV (variablesAt s sv) ρ₁) :
interpV (updateVariablesForState s sv) ρ₂ :=
eval_fold_valid hbss hvs
omit [DecidableEq L] in
omit [FiniteHeightLattice L] [DecidableEq L] in
/-- Agda: `updateAll-matches`. -/
theorem updateAll_matches {s : prog.State} {sv : StateVariables L prog}
{ρ₁ ρ₂ : Env} (hbss : EvalBasicStmts ρ₁ (prog.code s) ρ₂)
(hvs : interpV I (variablesAt s sv) ρ₁) :
interpV I (variablesAt s (updateAll E sv)) ρ₂ := by
(hvs : interpV (variablesAt s sv) ρ₁) :
interpV (variablesAt s (updateAll sv)) ρ₂ := by
rw [variablesAt_updateAll]
exact updateVariablesForState_matches hE hbss hvs
exact updateVariablesForState_matches hbss hvs
/-- Agda: `stepTrace`. -/
theorem stepTrace {s₁ : prog.State} {ρ₁ ρ₂ : Env}
(hjoin : interpV I (joinForKey fhL s₁ (result fhL E)) ρ₁)
(hjoin : interpV (joinForKey s₁ (result L prog)) ρ₁)
(hbss : EvalBasicStmts ρ₁ (prog.code s₁) ρ₂) :
interpV I (variablesAt s₁ (result fhL E)) ρ₂ := by
rw [result_eq fhL E]
refine updateAll_matches hE hbss ?_
interpV (variablesAt s₁ (result L prog)) ρ₂ := by
rw [result_eq L prog]
refine updateAll_matches hbss ?_
rw [variablesAt_joinAll]
exact hjoin
/-- Agda: `walkTrace`. -/
theorem walkTrace {s₁ s₂ : prog.State} {ρ₁ ρ₂ : Env}
(hjoin : interpV I (joinForKey fhL s₁ (result fhL E)) ρ₁)
(hjoin : interpV (joinForKey s₁ (result L prog)) ρ₁)
(tr : Trace prog.graph s₁ s₂ ρ₁ ρ₂) :
interpV I (variablesAt s₂ (result fhL E)) ρ₂ := by
interpV (variablesAt s₂ (result L prog)) ρ₂ := by
induction tr with
| single hbss => exact stepTrace fhL hE hjoin hbss
| single hbss => exact stepTrace hjoin hbss
| @edge _ ρ' _ i₁ i₂ _ hbss hedge _ ih =>
have hstep : interpV I (variablesAt i₁ (result fhL E)) ρ' :=
stepTrace fhL hE hjoin hbss
have hmem : variablesAt i₁ (result fhL E)
(result fhL E).valuesAt (prog.incoming i₂) :=
have hstep : interpV (variablesAt i₁ (result L prog)) ρ' :=
stepTrace hjoin hbss
have hmem : variablesAt i₁ (result L prog)
(result L prog).valuesAt (prog.incoming i₂) :=
FiniteMap.mem_valuesAt prog.states_nodup
(prog.mem_incoming_of_edge hedge) (variablesAt_mem i₁ (result fhL E))
exact ih (interpV_foldr fhL I hstep hmem)
(prog.mem_incoming_of_edge hedge) (variablesAt_mem i₁ (result L prog))
exact ih (interpV_foldr hstep hmem)
omit hE in
/-- Agda: `joinForKey-initialState-⊥ᵛ`. -/
theorem joinForKey_initialState :
joinForKey fhL prog.initialState (result fhL E) = botV L prog fhL := by
rw [joinForKey, prog.incoming_initialState_eq_nil]
rfl
omit hE in
omit V in
/-- Agda: `⟦joinAll-initialState⟧ᵛ∅`. -/
theorem interpV_joinForKey_initialState :
interpV I (joinForKey fhL prog.initialState (result fhL E)) [] := by
interpV (joinForKey prog.initialState (result L prog)) [] := by
rw [joinForKey_initialState]
exact interpV_botV_nil fhL I
exact interpV_botV_nil
variable (L prog) in
/-- Agda: `analyze-correct` — the analysis result at the final state soundly
describes every terminating execution of the program. -/
theorem analyze_correct {ρ : Env} (hrun : EvalStmt [] prog.rootStmt ρ) :
interpV I (variablesAt prog.finalState (result fhL E)) ρ :=
walkTrace fhL hE (interpV_joinForKey_initialState fhL (E := E) (I := I))
(prog.trace hrun)
interpV (variablesAt prog.finalState (result L prog)) ρ :=
walkTrace interpV_joinForKey_initialState (prog.trace hrun)
end Spa