diff --git a/_CoqProject b/_CoqProject index b8dc0d3f83c048a3f021884c4bc62bb73020af62..4820179c052dcaac62e15b72b0c19aec953040ed 100644 --- a/_CoqProject +++ b/_CoqProject @@ -57,6 +57,7 @@ theories/program_logic/adequacy.v theories/program_logic/lifting.v theories/program_logic/weakestpre.v theories/program_logic/total_weakestpre.v +theories/program_logic/total_adequacy.v theories/program_logic/hoare.v theories/program_logic/language.v theories/program_logic/ectx_language.v diff --git a/theories/program_logic/total_adequacy.v b/theories/program_logic/total_adequacy.v new file mode 100644 index 0000000000000000000000000000000000000000..648d934571fd8d628932554a45737a2c2c2040ec --- /dev/null +++ b/theories/program_logic/total_adequacy.v @@ -0,0 +1,129 @@ +From iris.program_logic Require Export total_weakestpre adequacy. +From iris.algebra Require Import gmap auth agree gset coPset. +From iris.base_logic Require Import big_op soundness fixpoint. +From iris.base_logic.lib Require Import wsat. +From iris.proofmode Require Import tactics. +Set Default Proof Using "Type". +Import uPred. + +Section adequacy. +Context `{irisG Λ Σ}. +Implicit Types e : expr Λ. + +Definition twptp_pre (twptp : list (expr Λ) → iProp Σ) + (t1 : list (expr Λ)) : iProp Σ := + (∀ t2 σ1 σ2, ⌜step (t1,σ1) (t2,σ2)⌠-∗ + state_interp σ1 ={⊤}=∗ state_interp σ2 ∗ twptp t2)%I. + +Lemma twptp_pre_mono (twptp1 twptp2 : list (expr Λ) → iProp Σ) : + ((â–¡ ∀ t, twptp1 t -∗ twptp2 t) → + ∀ t, twptp_pre twptp1 t -∗ twptp_pre twptp2 t)%I. +Proof. + iIntros "#H"; iIntros (t) "Hwp". rewrite /twptp_pre. + iIntros (t2 σ1 σ2) "Hstep Hσ". iMod ("Hwp" with "[$] [$]") as "[$ ?]". + by iApply "H". +Qed. + +Local Instance twptp_pre_mono' : BIMonoPred twptp_pre. +Proof. + constructor; first apply twptp_pre_mono. + intros wp Hwp n t1 t2 ?%(discrete_iff _ _)%leibniz_equiv; solve_proper. +Qed. + +Definition twptp (t : list (expr Λ)) : iProp Σ := + uPred_least_fixpoint twptp_pre t. + +Lemma twptp_unfold t : twptp t ⊣⊢ twptp_pre twptp t. +Proof. by rewrite /twptp least_fixpoint_unfold. Qed. + +Lemma twptp_ind Ψ : + ((â–¡ ∀ t, twptp_pre (λ t, Ψ t ∧ twptp t) t -∗ Ψ t) → ∀ t, twptp t -∗ Ψ t)%I. +Proof. + iIntros "#IH" (t) "H". + assert (NonExpansive Ψ). + { by intros n ?? ->%(discrete_iff _ _)%leibniz_equiv. } + iApply (least_fixpoint_strong_ind _ Ψ with "[] H"). + iIntros "!#" (t') "H". by iApply "IH". +Qed. + +Instance twptp_Permutation : Proper ((≡ₚ) ==> (⊢)) twptp. +Proof. + iIntros (t1 t1' Ht) "Ht1". iRevert (t1' Ht); iRevert (t1) "Ht1". + iApply twptp_ind; iIntros "!#" (t1) "IH"; iIntros (t1' Ht). + rewrite twptp_unfold /twptp_pre. iIntros (t2 σ1 σ2 Hstep) "Hσ". + destruct (step_Permutation t1' t1 t2 σ1 σ2) as (t2'&?&?); try done. + iMod ("IH" $! t2' with "[% //] Hσ") as "[$ [IH _]]". by iApply "IH". +Qed. + +Lemma twptp_app t1 t2 : twptp t1 -∗ twptp t2 -∗ twptp (t1 ++ t2). +Proof. + iIntros "H1". iRevert (t2). iRevert (t1) "H1". + iApply twptp_ind; iIntros "!#" (t1) "IH1". iIntros (t2) "H2". + iRevert (t1) "IH1"; iRevert (t2) "H2". + iApply twptp_ind; iIntros "!#" (t2) "IH2". iIntros (t1) "IH1". + rewrite twptp_unfold /twptp_pre. iIntros (t1'' σ1 σ2 Hstep) "Hσ1". + destruct Hstep as [e1 σ1' e2 σ2' efs' t1' t2' ?? Hstep]; simplify_eq/=. + apply app_eq_inv in H as [(t&?&?)|(t&?&?)]; subst. + - destruct t as [|e1' ?]; simplify_eq/=. + + iMod ("IH2" with "[%] Hσ1") as "[$ [IH2 _]]". + { by eapply step_atomic with (t1:=[]). } + iModIntro. rewrite -{2}(left_id_L [] (++) (e2 :: _)). iApply "IH2". + by setoid_rewrite (right_id_L [] (++)). + + iMod ("IH1" with "[%] Hσ1") as "[$ [IH1 _]]"; first by econstructor. + iAssert (twptp t2) with "[IH2]" as "Ht2". + { rewrite twptp_unfold. iApply (twptp_pre_mono with "[] IH2"). + iIntros "!# * [_ ?] //". } + iModIntro. rewrite -assoc_L (comm _ t2) !cons_middle !assoc_L. + by iApply "IH1". + - iMod ("IH2" with "[%] Hσ1") as "[$ [IH2 _]]"; first by econstructor. + iModIntro. rewrite -assoc. by iApply "IH2". +Qed. + +Lemma twp_twptp s Φ e : WP e @ s; ⊤ [{ Φ }] -∗ twptp [e]. +Proof. + iIntros "He". remember (⊤ : coPset) as E eqn:HE. + iRevert (HE). iRevert (e E Φ) "He". iApply twp_ind. + iIntros "!#" (e E Φ); iIntros "IH" (->). + rewrite twptp_unfold /twptp_pre /twp_pre. iIntros (t1' σ1' σ2' Hstep) "Hσ1". + destruct Hstep as [e1 σ1 e2 σ2 efs [|? t1] t2 ?? Hstep]; + simplify_eq/=; try discriminate_list. + destruct (to_val e1) as [v|] eqn:He1. + { apply val_stuck in Hstep; naive_solver. } + iMod ("IH" with "Hσ1") as "[_ IH]". + iMod ("IH" with "[% //]") as "[$ [[IH _] IHfork]]"; iModIntro. + iApply (twptp_app [_] with "[IH]"); first by iApply "IH". + clear. iInduction efs as [|e efs] "IH"; simpl. + { rewrite twptp_unfold /twptp_pre. iIntros (t2 σ1 σ2 Hstep). + destruct Hstep; simplify_eq/=; discriminate_list. } + iDestruct "IHfork" as "[[IH' _] IHfork]". + iApply (twptp_app [_] with "[IH']"); [by iApply "IH'"|by iApply "IH"]. +Qed. + +Notation world σ := (wsat ∗ ownE ⊤ ∗ state_interp σ)%I. + +Lemma twptp_total σ t : world σ -∗ twptp t -∗ â–· ⌜sn step (t, σ)âŒ. +Proof. + iIntros "Hw Ht". iRevert (σ) "Hw". iRevert (t) "Ht". + iApply twptp_ind; iIntros "!#" (t) "IH"; iIntros (σ) "(Hw&HE&Hσ)". + iApply (pure_mono _ _ (Acc_intro _)). iIntros ([t' σ'] Hstep). + rewrite /twptp_pre fupd_eq /fupd_def. + iMod ("IH" with "[% //] Hσ [$Hw $HE]") as ">(Hw & HE & Hσ & [IH _])". + iApply "IH". by iFrame. +Qed. +End adequacy. + +Theorem twp_total Σ Λ `{invPreG Σ} s e σ Φ : + (∀ `{Hinv : invG Σ}, + (|={⊤}=> ∃ stateI : state Λ → iProp Σ, + let _ : irisG Λ Σ := IrisG _ _ Hinv stateI in + stateI σ ∗ WP e @ s; ⊤ [{ Φ }])%I) → + sn step ([e], σ). (* i.e. ([e], σ) is strongly normalizing *) +Proof. + intros Hwp. + eapply (soundness (M:=iResUR Σ) _ 1); iIntros "/=". + iMod wsat_alloc as (Hinv) "[Hw HE]". + rewrite fupd_eq in Hwp; iMod (Hwp with "[$Hw $HE]") as ">(Hw & HE & Hwp)". + iDestruct "Hwp" as (Istate) "[HI Hwp]". + iApply (@twptp_total _ _ (IrisG _ _ Hinv Istate) with "[$Hw $HE $HI]"). + by iApply (@twp_twptp _ _ (IrisG _ _ Hinv Istate)). +Qed.