Migrate most of the codebase (sans Reaching.lean / LICM left) to projections

This commit is contained in:
2026-07-01 22:56:29 -05:00
parent 10b8fa97ca
commit 0e6976f9b4
7 changed files with 139 additions and 136 deletions

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@@ -55,70 +55,38 @@ lemma joinForKey_initialState :
class ValidStateEvaluator (L : Type) [FiniteHeightLattice L] (prog : Program)
[E : StmtEvaluator L prog] [S : StateInterpretation L prog] where
step : (s : prog.State) → {ρ₁ ρ₂ : Env} → EvalBasicStmtOpt ρ₁ (prog.code s) ρ₂ → S.St ρ₁ → S.St ρ₂
valid : ∀ (s : prog.State) {ρ₁ ρ₂ : Env}
{vs : VariableValues L prog} {st : S.St ρ₁},
(hbs : EvalBasicStmtOpt ρ₁ (prog.code s) ρ₂) → ⟦ vs ⟧ ρ₁ st →
⟦ E.eval s vs ⟧ ρ₂ (step s hbs st)
botV_init : ⟦ botV L prog ⟧ [] S.init
valid : ∀ (s₁ s₂ : prog.State) {ρ₁ ρ₂ ρ₃: Env}
{vs : VariableValues L prog},
(tr : Traceₗ prog.cfg s₁ s₂ ρ₁ ρ₂) →
(hbs : EvalBasicStmtOpt ρ₂ (prog.cfg.nodes s₂) ρ₃) → ⟦ vs ⟧ (S.Pre tr) →
⟦ E.eval s₂ vs ⟧ (S.Post (tr ++ hbs))
botV_init : ⟦ botV L prog ⟧ (S.Pre (Traceₗ.single prog.cfg prog.initialState []))
instance [LatticeInterpretation L] [ValidStmtEvaluator L prog] :
ValidStateEvaluator L prog where
step := by intro _ _ _ _ _; exact PUnit.unit
valid := by intro _ _ _ _ _ hbs hvs; exact ValidStmtEvaluator.valid hbs hvs
valid := by intro _ _ _ _ _ _ tr hbs hvs; exact ValidStmtEvaluator.valid hbs hvs
botV_init := by intro k l _ v hmem; cases hmem
section
variable [S : StateInterpretation L prog] [V : ValidStateEvaluator L prog]
noncomputable def stepNode (s : prog.State) {ρ₁ ρ₂ : Env}
(h : EvalBasicStmtOpt ρ₁ (prog.code s) ρ₂) (st : S.St ρ₁) : S.St ρ₂ :=
V.step s h st
noncomputable def stepTraceState :
{s₁ s₂ : prog.State} → {ρ₁ ρ₂ : Env} →
Trace prog.cfg s₁ s₂ ρ₁ ρ₂ → S.St ρ₁ → S.St ρ₂
| s₁, _, _, _, .single hnode, st => stepNode s₁ hnode st
| s₁, _, _, _, .edge hnode _ subtr, st =>
stepTraceState subtr (stepNode s₁ hnode st)
/-- `Reaches tr st₁ s ρin ρout stin stout` witnesses that, when the trace `tr`
(starting at state `st₁`) is executed, node `s` is visited at some point: `ρin`
and `ρout` are the concrete environments just before and after `s`'s basic block
runs, and `stin`/`stout` are the corresponding abstract execution states. A node
inside a loop is reached once per iteration, each with its own environments. -/
inductive Reaches : {s₁ s₂ : prog.State} → {ρ₁ ρ₂ : Env} →
Trace prog.cfg s₁ s₂ ρ₁ ρ₂ → S.St ρ₁ →
(s : prog.State) → (ρin ρout : Env) → S.St ρin → S.St ρout → Prop
| single_here {s₁ : prog.State} {ρ₁ ρ₂ : Env} {st₁ : S.St ρ₁}
(hnode : EvalBasicStmtOpt ρ₁ (prog.code s₁) ρ₂) :
Reaches (.single hnode) st₁ s₁ ρ₁ ρ₂ st₁ (stepNode s₁ hnode st₁)
| edge_here {s₁ s₂ s₃ : prog.State} {ρ₁ ρ₂ ρ₃ : Env} {st₁ : S.St ρ₁}
(hnode : EvalBasicStmtOpt ρ₁ (prog.code s₁) ρ₂)
(hedge : (s₁, s₂) ∈ prog.cfg.edges) (rest : Trace prog.cfg s₂ s₃ ρ₂ ρ₃) :
Reaches (.edge hnode hedge rest) st₁ s₁ ρ₁ ρ₂ st₁ (stepNode s₁ hnode st₁)
| edge_there {s₁ s₂ s₃ : prog.State} {ρ₁ ρ₂ ρ₃ : Env} {st₁ : S.St ρ₁}
(hnode : EvalBasicStmtOpt ρ₁ (prog.code s₁) ρ₂)
(hedge : (s₁, s₂) ∈ prog.cfg.edges) (rest : Trace prog.cfg s₂ s₃ ρ₂ ρ₃)
{s : prog.State} {ρin ρout : Env} {stin : S.St ρin} {stout : S.St ρout} :
Reaches rest (stepNode s₁ hnode st₁) s ρin ρout stin stout →
Reaches (.edge hnode hedge rest) st₁ s ρin ρout stin stout
omit [DecidableEq L] in
lemma updateAll_matches {s : prog.State} {sv : StateVariables L prog}
{ρ₁ ρ₂ : Env} {st : S.St ρ₁}
(hnode : EvalBasicStmtOpt ρ₁ (prog.code s) ρ₂)
(hvs : ⟦ variablesAt s sv ⟧ ρ₁ st) :
⟦ variablesAt s (updateAll sv) ⟧ ρ₂ (stepNode s hnode st) := by
lemma updateAll_matches {s₁ s₂ : prog.State} {sv : StateVariables L prog}
{ρ₁ ρ₂ ρ₃ : Env}
(tr : Traceₗ prog.cfg s₁ s₂ ρ₁ ρ₂)
(hnode : EvalBasicStmtOpt ρ₂ (prog.code s₂) ρ₃)
(hvs : ⟦ variablesAt s₂ sv ⟧ (S.Pre tr)) :
⟦ variablesAt s₂ (updateAll sv) ⟧ (S.Post (tr ++ hnode)) := by
rw [variablesAt_updateAll]
exact V.valid s hnode hvs
exact V.valid s₁ s₂ tr hnode hvs
lemma stepTrace {s₁ : prog.State} {ρ₁ ρ₂ : Env} {st : S.St ρ₁}
(hjoin : ⟦ joinForKey s₁ (result L prog) ⟧ ρ₁ st)
(hnode : EvalBasicStmtOpt ρ₁ (prog.code s₁) ρ₂) :
⟦ variablesAt s₁ (result L prog) ⟧ ρ₂ (stepNode s₁ hnode st) := by
lemma stepTrace {s₁ s₂ : prog.State} {ρ₁ ρ₂ : Env}
(tr : Traceₗ prog.cfg s₁ s₂ ρ₁ ρ₂)
(hjoin : ⟦ joinForKey s₂ (result L prog) ⟧ (S.Pre tr))
(hnode : EvalBasicStmtOpt ρ₂ (prog.code s₂) ρ₃) :
⟦ variablesAt s₂ (result L prog) ⟧ (S.Post (tr ++ hnode)) := by
rw [result_eq L prog]
refine updateAll_matches hnode ?_
refine updateAll_matches tr hnode ?_
rw [variablesAt_joinAll]
exact hjoin
@@ -127,49 +95,41 @@ lemma stepTrace {s₁ : prog.State} {ρ₁ ρ₂ : Env} {st : S.St ρ₁}
way it over-approximates both the environment entering that node (via `joinForKey`)
and the environment leaving it (via `variablesAt`). The intermediate `variablesAt`
evidence used to be computed and discarded inside `walkTrace`; here it is returned. -/
lemma walkTrace_reaches {s₁ s₂ : prog.State} {ρ₁ ρ₂ : Env} {st₁ : S.St ρ₁}
{s : prog.State} {ρin ρout : Env} {stin : S.St ρin} {stout : S.St ρout}
{tr : Trace prog.cfg s₁ s₂ ρ₁ ρ₂}
(hr : Reaches tr st₁ s ρin ρout stin stout)
(hjoin : ⟦ joinForKey s₁ (result L prog) ⟧ ρ₁ st₁) :
⟦ joinForKey s (result L prog) ⟧ ρin stin
∧ ⟦ variablesAt s (result L prog) ⟧ ρout stout := by
lemma walkTrace_reaches {s₁ s₂ s₃: prog.State} {ρ₁ ρ₂ ρ₃: Env}
{s : prog.State} {ρin ρout : Env}
{tr : Trace prog.cfg s₂ s₃ ρ₂ ρ₃}
(hr : Reaches tr s ρin ρout)
(trₗ : Traceₗ prog.cfg s₁ s₂ ρ₁ ρ₂)
(hjoin : ⟦ joinForKey s₂ (result L prog) ⟧ (S.Pre trₗ)) :
⟦ joinForKey s (result L prog) ⟧ (S.Pre (trₗ ++ hr.pre))
∧ ⟦ variablesAt s (result L prog) ⟧ (S.Post (trₗ ++ hr.post)) := by
induction hr with
| single_here hnode => exact ⟨hjoin, stepTrace hjoin hnode⟩
| edge_here hnode hedge rest => exact ⟨hjoin, stepTrace hjoin hnode⟩
| single_here hnode =>
simp [Reaches.pre, Reaches.post]
refine ⟨?_, ?_⟩ <;> try simpa [HAppend.hAppend]
exact stepTrace trₗ hjoin hnode
| edge_here hnode hedge rest =>
simp [Reaches.pre, Reaches.post]
refine ⟨?_, ?_⟩ <;> try simpa [HAppend.hAppend]
exact stepTrace trₗ hjoin hnode
| edge_there hnode hedge rest hr' ih =>
have hstep := stepTrace hjoin hnode
have hstep := stepTrace trₗ hjoin hnode
have hmem := FiniteMap.mem_valuesAt prog.states_nodup
(prog.mem_incoming_of_edge hedge) (variablesAt_mem _ (result L prog))
exact ih (interp_foldr hstep hmem)
simpa [Reaches.pre, Reaches.post, HAppend.hAppend] using
ih ((trₗ ++ hnode).addEdge hedge)
(interp_foldr (S.post_pre (trₗ ++ hnode) hedge hstep) hmem)
omit [DecidableEq L] in
/-- The final node of a trace is always reached, with the environment/state the trace
ends in. Used to recover the final-state soundness theorem from `walkTrace_reaches`. -/
lemma reaches_final {s₁ s₂ : prog.State} {ρ₁ ρ₂ : Env} (st₁ : S.St ρ₁)
def reaches_final {s₁ s₂ : prog.State} {ρ₁ ρ₂ : Env}
(tr : Trace prog.cfg s₁ s₂ ρ₁ ρ₂) :
∃ ρin, ∃ stin : S.St ρin,
Reaches tr st₁ s₂ ρin ρ₂ stin (stepTraceState tr st₁) := by
induction tr with
| single hnode => exact ⟨_, _, .single_here hnode⟩
| edge hnode hedge rest ih =>
obtain ⟨ρin, stin, hr⟩ := ih (stepNode _ hnode st₁)
exact ⟨ρin, stin, .edge_there hnode hedge rest hr⟩
lemma walkTrace {s₁ s₂ : prog.State} {ρ₁ ρ₂ : Env} {st₁ : S.St ρ₁}
(hjoin : ⟦ joinForKey s₁ (result L prog) ⟧ ρ₁ st₁)
(tr : Trace prog.cfg s₁ s₂ ρ₁ ρ₂) :
⟦ variablesAt s₂ (result L prog) ⟧ ρ₂ (stepTraceState tr st₁) := by
obtain ⟨_, _, hr⟩ := reaches_final st₁ tr
exact (walkTrace_reaches hr hjoin).2
variable (L prog) in
theorem analyze_correct_state {ρ : Env} (hrun : EvalStmt [] prog.rootStmt ρ) :
⟦ variablesAt prog.finalState (result L prog) ⟧ ρ
(stepTraceState (prog.trace hrun) S.init) := by
refine walkTrace ?_ (prog.trace hrun)
rw [joinForKey_initialState]
exact ValidStateEvaluator.botV_init
Σ ρin, Reaches tr s₂ ρin ρ₂ :=
match tr with
| .single hnode => ⟨_, .single_here hnode⟩
| .edge hnode hedge rest =>
let ⟨ρin, r'⟩ := reaches_final rest; ⟨ρin, .edge_there hnode hedge _ r'⟩
variable (L prog) in
/-- Soundness at every program point reached during execution: for any node `s` visited
@@ -177,21 +137,30 @@ variable (L prog) in
environment entering `s` and the one leaving it. The final-state theorem
`analyze_correct_state` is the special case where `s` is `prog.finalState`. -/
theorem analyze_correct_at {ρf : Env} (hrun : EvalStmt [] prog.rootStmt ρf)
{s : prog.State} {ρin ρout : Env} {stin : S.St ρin} {stout : S.St ρout}
(hr : Reaches (prog.trace hrun) S.init s ρin ρout stin stout) :
⟦ joinForKey s (result L prog) ⟧ ρin stin
∧ ⟦ variablesAt s (result L prog) ⟧ ρout stout := by
refine walkTrace_reaches hr ?_
{s : prog.State} {ρin ρout : Env}
(hr : Reaches (prog.trace hrun) s ρin ρout) :
⟦ joinForKey s (result L prog) ⟧ (S.Pre hr.pre)
∧ ⟦ variablesAt s (result L prog) ⟧ (S.Post hr.post) := by
refine walkTrace_reaches hr (Traceₗ.single _ _ []) ?_
rw [joinForKey_initialState]
exact ValidStateEvaluator.botV_init
variable (L prog) in
theorem analyze_correct'
{ρ : Env} (hrun : EvalStmt [] prog.rootStmt ρ) :
⟦ variablesAt prog.finalState (result L prog) ⟧ (S.Post (reaches_final (prog.trace hrun)).2.post) := by
let idk₀ := prog.trace hrun
have ⟨_, idk₁⟩ := reaches_final idk₀
have ⟨_, idk₂⟩ := analyze_correct_at L prog hrun idk₁
assumption
end
variable (L prog) in
theorem analyze_correct [LatticeInterpretation L] [ValidStmtEvaluator L prog]
{ρ : Env} (hrun : EvalStmt [] prog.rootStmt ρ) :
⟦ variablesAt prog.finalState (result L prog) ⟧ ρ () :=
analyze_correct_state L prog hrun
⟦ variablesAt prog.finalState (result L prog) ⟧ ρ :=
analyze_correct' L prog hrun
end Forward