Split the Language file into modules

Signed-off-by: Danila Fedorin <danila.fedorin@gmail.com>
This commit is contained in:
2024-04-13 18:39:38 -07:00
parent 7ed7f20227
commit de956cdc6a
5 changed files with 508 additions and 481 deletions

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module Language.Graphs where
open import Language.Base
open import Language.Semantics
open import Data.Fin as Fin using (Fin; suc; zero; _↑ˡ_; _↑ʳ_)
open import Data.Fin.Properties as FinProp using (suc-injective)
open import Data.List as List using (List; []; _∷_)
open import Data.List.Membership.Propositional as ListMem using ()
open import Data.List.Membership.Propositional.Properties as ListMemProp using ()
open import Data.Nat as Nat using (ℕ; suc)
open import Data.Nat.Properties using (+-assoc; +-comm)
open import Data.Product using (_×_; Σ; _,_)
open import Data.Vec using (Vec; []; _∷_; lookup; cast; _++_)
open import Data.Vec.Properties using (cast-is-id; ++-assoc; lookup-++ˡ; cast-sym; ++-identityʳ)
open import Relation.Binary.PropositionalEquality as Eq using (_≡_; sym; refl; subst)
open import Lattice
open import Utils using (x∈xs⇒fx∈fxs; _⊗_; _,_)
record Graph : Set where
constructor MkGraph
field
size : ℕ
Index : Set
Index = Fin size
Edge : Set
Edge = Index × Index
field
nodes : Vec (List BasicStmt) size
edges : List Edge
empty : Graph
empty = record
{ size = 0
; nodes = []
; edges = []
}
↑ˡ-Edge : ∀ {n} → (Fin n × Fin n) → ∀ m → (Fin (n Nat.+ m) × Fin (n Nat.+ m))
↑ˡ-Edge (idx₁ , idx₂) m = (idx₁ ↑ˡ m , idx₂ ↑ˡ m)
_[_] : ∀ (g : Graph) → Graph.Index g → List BasicStmt
_[_] g idx = lookup (Graph.nodes g) idx
record _⊆_ (g₁ g₂ : Graph) : Set where
constructor Mk-⊆
field
n : ℕ
sg₂≡sg₁+n : Graph.size g₂ ≡ Graph.size g₁ Nat.+ n
newNodes : Vec (List BasicStmt) n
nsg₂≡nsg₁++newNodes : cast sg₂≡sg₁+n (Graph.nodes g₂) ≡ Graph.nodes g₁ ++ newNodes
e∈g₁⇒e∈g₂ : ∀ {e : Graph.Edge g₁} →
e ListMem.∈ (Graph.edges g₁) →
(↑ˡ-Edge e n) ListMem.∈ (subst (λ m → List (Fin m × Fin m)) sg₂≡sg₁+n (Graph.edges g₂))
castᵉ : ∀ {n m : ℕ} .(p : n ≡ m) → (Fin n × Fin n) → (Fin m × Fin m)
castᵉ p (idx₁ , idx₂) = (Fin.cast p idx₁ , Fin.cast p idx₂)
↑ˡ-assoc : ∀ {s n₁ n₂} (f : Fin s) (p : s Nat.+ (n₁ Nat.+ n₂) ≡ s Nat.+ n₁ Nat.+ n₂) →
f ↑ˡ n₁ ↑ˡ n₂ ≡ Fin.cast p (f ↑ˡ (n₁ Nat.+ n₂))
↑ˡ-assoc zero p = refl
↑ˡ-assoc {suc s'} {n₁} {n₂} (suc f') p rewrite ↑ˡ-assoc f' (sym (+-assoc s' n₁ n₂)) = refl
↑ˡ-Edge-assoc : ∀ {s n₁ n₂} (e : Fin s × Fin s) (p : s Nat.+ (n₁ Nat.+ n₂) ≡ s Nat.+ n₁ Nat.+ n₂) →
↑ˡ-Edge (↑ˡ-Edge e n₁) n₂ ≡ castᵉ p (↑ˡ-Edge e (n₁ Nat.+ n₂))
↑ˡ-Edge-assoc (idx₁ , idx₂) p
rewrite ↑ˡ-assoc idx₁ p
rewrite ↑ˡ-assoc idx₂ p = refl
↑ˡ-identityʳ : ∀ {s} (f : Fin s) (p : s Nat.+ 0 ≡ s) →
f ≡ Fin.cast p (f ↑ˡ 0)
↑ˡ-identityʳ zero p = refl
↑ˡ-identityʳ {suc s'} (suc f') p rewrite sym (↑ˡ-identityʳ f' (+-comm s' 0)) = refl
↑ˡ-Edge-identityʳ : ∀ {s} (e : Fin s × Fin s) (p : s Nat.+ 0 ≡ s) →
e ≡ castᵉ p (↑ˡ-Edge e 0)
↑ˡ-Edge-identityʳ (idx₁ , idx₂) p
rewrite sym (↑ˡ-identityʳ idx₁ p)
rewrite sym (↑ˡ-identityʳ idx₂ p) = refl
cast∈⇒∈subst : ∀ {n m : ℕ} (p : n ≡ m) (q : m ≡ n)
(e : Fin n × Fin n) (es : List (Fin m × Fin m)) →
castᵉ p e ListMem.∈ es →
e ListMem.∈ subst (λ m → List (Fin m × Fin m)) q es
cast∈⇒∈subst refl refl (idx₁ , idx₂) es e∈es
rewrite FinProp.cast-is-id refl idx₁
rewrite FinProp.cast-is-id refl idx₂ = e∈es
⊆-trans : ∀ {g₁ g₂ g₃ : Graph} → g₁ ⊆ g₂ → g₂ ⊆ g₃ → g₁ ⊆ g₃
⊆-trans {MkGraph s₁ ns₁ es₁} {MkGraph s₂ ns₂ es₂} {MkGraph s₃ ns₃ es₃}
(Mk-⊆ n₁ p₁@refl newNodes₁ nsg₂≡nsg₁++newNodes₁ e∈g₁⇒e∈g₂)
(Mk-⊆ n₂ p₂@refl newNodes₂ nsg₃≡nsg₂++newNodes₂ e∈g₂⇒e∈g₃)
rewrite cast-is-id refl ns₂
rewrite cast-is-id refl ns₃
with refl ← nsg₂≡nsg₁++newNodes₁
with refl ← nsg₃≡nsg₂++newNodes₂ =
record
{ n = n₁ Nat.+ n₂
; sg₂≡sg₁+n = +-assoc s₁ n₁ n₂
; newNodes = newNodes₁ ++ newNodes₂
; nsg₂≡nsg₁++newNodes = ++-assoc (+-assoc s₁ n₁ n₂) ns₁ newNodes₁ newNodes₂
; e∈g₁⇒e∈g₂ = λ {e} e∈g₁ →
cast∈⇒∈subst (sym (+-assoc s₁ n₁ n₂)) (+-assoc s₁ n₁ n₂) _ _
(subst (λ e' → e' ListMem.∈ es₃)
(↑ˡ-Edge-assoc e (sym (+-assoc s₁ n₁ n₂)))
(e∈g₂⇒e∈g₃ (e∈g₁⇒e∈g₂ e∈g₁)))
}
record Relaxable (T : Graph → Set) : Set where
field relax : ∀ {g₁ g₂ : Graph} → g₁ ⊆ g₂ → T g₁ → T g₂
instance
IndexRelaxable : Relaxable Graph.Index
IndexRelaxable = record
{ relax = λ { (Mk-⊆ n refl _ _ _) idx → idx ↑ˡ n }
}
EdgeRelaxable : Relaxable Graph.Edge
EdgeRelaxable = record
{ relax = λ g₁⊆g₂ (idx₁ , idx₂) →
( Relaxable.relax IndexRelaxable g₁⊆g₂ idx₁
, Relaxable.relax IndexRelaxable g₁⊆g₂ idx₂
)
}
ProdRelaxable : ∀ {P : Graph → Set} {Q : Graph → Set} →
{{ PRelaxable : Relaxable P }} → {{ QRelaxable : Relaxable Q }} →
Relaxable (P ⊗ Q)
ProdRelaxable {{pr}} {{qr}} = record
{ relax = (λ { g₁⊆g₂ (p , q) →
( Relaxable.relax pr g₁⊆g₂ p
, Relaxable.relax qr g₁⊆g₂ q) }
)
}
open Relaxable {{...}} public
relax-preserves-[]≡ : ∀ (g₁ g₂ : Graph) (g₁⊆g₂ : g₁ ⊆ g₂) (idx : Graph.Index g₁) →
g₁ [ idx ] ≡ g₂ [ relax g₁⊆g₂ idx ]
relax-preserves-[]≡ g₁ g₂ (Mk-⊆ n refl newNodes nsg₂≡nsg₁++newNodes _) idx
rewrite cast-is-id refl (Graph.nodes g₂)
with refl ← nsg₂≡nsg₁++newNodes = sym (lookup-++ˡ (Graph.nodes g₁) _ _)
-- Tools for graph construction. The most important is a 'monotonic function':
-- one that takes a graph, and produces another graph, such that the
-- new graph includes all the information from the old one.
MonotonicGraphFunction : (Graph → Set) → Set
MonotonicGraphFunction T = (g₁ : Graph) → Σ Graph (λ g₂ → T g₂ × g₁ ⊆ g₂)
-- Now, define some operations on monotonic functions; these are useful
-- to save the work of threading intermediate graphs in and out of operations.
infixr 2 _⟨⊗⟩_
_⟨⊗⟩_ : ∀ {T₁ T₂ : Graph → Set} {{ T₁Relaxable : Relaxable T₁ }} →
MonotonicGraphFunction T₁ → MonotonicGraphFunction T₂ →
MonotonicGraphFunction (T₁ ⊗ T₂)
_⟨⊗⟩_ {{r}} f₁ f₂ g
with (g' , (t₁ , g⊆g')) ← f₁ g
with (g'' , (t₂ , g'⊆g'')) ← f₂ g' =
(g'' , ((Relaxable.relax r g'⊆g'' t₁ , t₂) , ⊆-trans g⊆g' g'⊆g''))
infixl 2 _update_
_update_ : ∀ {T : Graph → Set} {{ TRelaxable : Relaxable T }} →
MonotonicGraphFunction T → (∀ (g : Graph) → T g → Σ Graph (λ g' → g ⊆ g')) →
MonotonicGraphFunction T
_update_ {{r}} f mod g
with (g' , (t , g⊆g')) ← f g
with (g'' , g'⊆g'') ← mod g' t =
(g'' , ((Relaxable.relax r g'⊆g'' t , ⊆-trans g⊆g' g'⊆g'')))
infixl 2 _map_
_map_ : ∀ {T₁ T₂ : Graph → Set} →
MonotonicGraphFunction T₁ → (∀ (g : Graph) → T₁ g → T₂ g) →
MonotonicGraphFunction T₂
_map_ f fn g = let (g' , (t₁ , g⊆g')) = f g in (g' , (fn g' t₁ , g⊆g'))
-- To reason about monotonic functions and what we do, we need a way
-- to describe values they produce. A 'graph-value predicate' is
-- just a predicate for some (dependent) value.
GraphValuePredicate : (Graph → Set) → Set₁
GraphValuePredicate T = ∀ (g : Graph) → T g → Set
Both : {T₁ T₂ : Graph → Set} → GraphValuePredicate T₁ → GraphValuePredicate T₂ →
GraphValuePredicate (T₁ ⊗ T₂)
Both P Q = (λ { g (t₁ , t₂) → (P g t₁ × Q g t₂) })
-- Since monotnic functions keep adding on to a function, proofs of
-- graph-value predicates go stale fast (they describe old values of
-- the graph). To keep propagating them through, we need them to still
-- on 'bigger graphs'. We call such predicates monotonic as well, since
-- they respect the ordering of graphs.
MonotonicPredicate : ∀ {T : Graph → Set} {{ TRelaxable : Relaxable T }} →
GraphValuePredicate T → Set
MonotonicPredicate {T} P = ∀ (g₁ g₂ : Graph) (t₁ : T g₁) (g₁⊆g₂ : g₁ ⊆ g₂) →
P g₁ t₁ → P g₂ (relax g₁⊆g₂ t₁)
-- A 'map' has a certain property if its ouputs satisfy that property
-- for all inputs.
always : ∀ {T : Graph → Set} → GraphValuePredicate T → MonotonicGraphFunction T → Set
always P m = ∀ g₁ → let (g₂ , t , _) = m g₁ in P g₂ t
⟨⊗⟩-reason : ∀ {T₁ T₂ : Graph → Set} {{ T₁Relaxable : Relaxable T₁ }}
{P : GraphValuePredicate T₁} {Q : GraphValuePredicate T₂}
{P-Mono : MonotonicPredicate P}
{m₁ : MonotonicGraphFunction T₁} {m₂ : MonotonicGraphFunction T₂} →
always P m₁ → always Q m₂ → always (Both P Q) (m₁ ⟨⊗⟩ m₂)
⟨⊗⟩-reason {P-Mono = P-Mono} {m₁ = m₁} {m₂ = m₂} aP aQ g
with p ← aP g
with (g' , (t₁ , g⊆g')) ← m₁ g
with q ← aQ g'
with (g'' , (t₂ , g'⊆g'')) ← m₂ g' = (P-Mono _ _ _ g'⊆g'' p , q)
module Construction where
pushBasicBlock : List BasicStmt → MonotonicGraphFunction Graph.Index
pushBasicBlock bss g =
( record
{ size = Graph.size g Nat.+ 1
; nodes = Graph.nodes g ++ (bss ∷ [])
; edges = List.map (λ e → ↑ˡ-Edge e 1) (Graph.edges g)
}
, ( Graph.size g ↑ʳ zero
, record
{ n = 1
; sg₂≡sg₁+n = refl
; newNodes = (bss ∷ [])
; nsg₂≡nsg₁++newNodes = cast-is-id refl _
; e∈g₁⇒e∈g₂ = λ e∈g₁ → x∈xs⇒fx∈fxs (λ e → ↑ˡ-Edge e 1) e∈g₁
}
)
)
addEdges : ∀ (g : Graph) → List (Graph.Edge g) → Σ Graph (λ g' → g ⊆ g')
addEdges (MkGraph s ns es) es' =
( record
{ size = s
; nodes = ns
; edges = es' List.++ es
}
, record
{ n = 0
; sg₂≡sg₁+n = +-comm 0 s
; newNodes = []
; nsg₂≡nsg₁++newNodes = cast-sym _ (++-identityʳ (+-comm s 0) ns)
; e∈g₁⇒e∈g₂ = λ {e} e∈es →
cast∈⇒∈subst (+-comm s 0) (+-comm 0 s) _ _
(subst (λ e' → e' ListMem.∈ _)
(↑ˡ-Edge-identityʳ e (+-comm s 0))
(ListMemProp.∈-++⁺ʳ es' e∈es))
}
)
pushEmptyBlock : MonotonicGraphFunction Graph.Index
pushEmptyBlock = pushBasicBlock []
buildCfg : Stmt → MonotonicGraphFunction (Graph.Index ⊗ Graph.Index)
buildCfg ⟨ bs₁ ⟩ = pushBasicBlock (bs₁ ∷ []) map (λ g idx → (idx , idx))
buildCfg (s₁ then s₂) =
(buildCfg s₁ ⟨⊗⟩ buildCfg s₂)
update (λ { g ((idx₁ , idx₂) , (idx₃ , idx₄)) → addEdges g ((idx₂ , idx₃) ∷ []) })
map (λ { g ((idx₁ , idx₂) , (idx₃ , idx₄)) → (idx₁ , idx₄) })
buildCfg (if _ then s₁ else s₂) =
(buildCfg s₁ ⟨⊗⟩ buildCfg s₂ ⟨⊗⟩ pushEmptyBlock ⟨⊗⟩ pushEmptyBlock)
update (λ { g ((idx₁ , idx₂) , (idx₃ , idx₄) , idx , idx') →
addEdges g ((idx , idx₁) ∷ (idx , idx₃) ∷ (idx₂ , idx') ∷ (idx₄ , idx') ∷ []) })
map (λ { g ((idx₁ , idx₂) , (idx₃ , idx₄) , idx , idx') → (idx , idx') })
buildCfg (while _ repeat s) =
(buildCfg s ⟨⊗⟩ pushEmptyBlock ⟨⊗⟩ pushEmptyBlock)
update (λ { g ((idx₁ , idx₂) , idx , idx') →
addEdges g ((idx , idx') ∷ (idx , idx₁) ∷ (idx₂ , idx) ∷ []) })
map (λ { g ((idx₁ , idx₂) , idx , idx') → (idx , idx') })