***********************************************************************
*                                                                     *
*            The CertiKOS Certified Kit Operating System              *
*                                                                     *
*                   The FLINT Group, Yale University                  *
*                                                                     *
*  Copyright The FLINT Group, Yale University.  All rights reserved.  *
*  This file is distributed under the terms of the Yale University    *
*  Non-Commercial License Agreement.                                  *
*                                                                     *
*********************************************************************** 

Require Import PTIntroGenDef.
Require Export PTIntroGenAccessorDef.

Section Refinement.

  Section WITHMEM.

    Context `{Hstencil: Stencil}.
    Context `{Hmem: Mem.MemoryModel}.
    Context `{Hmwd: UseMemWithData mem}.

    Require Import LoadStoreSem1.
    Require Import XOmega.
    Require Import HostAccess1.
    Require Import GuestAccessIntel1.
    Require Import HostAccess2.
    Require Import LoadStoreGeneral.

    Notation hStore := (fun F V ⇒ exec_storeex2 (flatmem_store := flatmem_store) (F:=F) (V:=V)).

    Notation lStore := (fun F V ⇒ exec_storeex1 (flatmem_store := flatmem_store) (F:=F) (V:=V)).

    Lemma store_correct:
      store_accessor_sim_def HDATAOps LDATAOps (one_crel HDATA LDATA) hStore lStore.
    Proof.
      unfold store_accessor_sim_def. intros.
      pose proof H2 as Hmatch.
      inv H2. inv match_extcall_states.

      unfold exec_storeex2 in ×.
      unfold exec_storeex1.
      unfold exec_host_store1, exec_host_store2 in ×.
      inv H4.
      exploit (eval_addrmode_correct ge1 ge2 a); eauto. intros HW.
      Local Opaque Z.sub.
      simpl in ×. revert H1. inv match_related. subrewrite´´. intros HLoad.
      destruct (eval_addrmode ge1 a rs1) eqn: Hev; contra_inv.
      -
        inv HW. destruct (ihost d2) eqn:HPH; contra_inv.
        destruct (pg d2) eqn:HPE; contra_inv.
        destruct (ikern d2) eqn:HPK; contra_inv.
        specialize (valid_PT refl_equal).
        +
          generalize match_match; intros HM. inv match_match.
          inv H1. inv relate_PT_re.
          ×
            rewrite <- H7 in valid_PT; omega.
          × assert (HFB: Genv.find_symbol ge2 PTPool_LOC = Some b).
            {
              inv H0. congruence.
            }
            rewrite HFB. lift_trivial. rewrite H8.
            assert (valid_PT´: 0 ≤ PT d1 < 64) by omega.
            specialize (H5 _ valid_PT´).
            set (pt := (ZMap.get (PT d1) (ptpool d1))) in ×. inv H5.
            assert (HI: 0≤ PDX (Int.unsigned i) ≤ PDX Int.max_unsigned).
            {
              specialize (Int.unsigned_range_2 i).
              clear. unfold PDX. Local Transparent Z.sub.
              xomega. Local Opaque Z.sub.
            }
            specialize (H7 _ HI).
            destruct H7 as [v[HLD [_ HP]]].
            assert (HI1: 0≤ PTX (Int.unsigned i) ≤ PTX Int.max_unsigned).
            {
              unfold PTX; change ((Int.max_unsigned / 4096) mod 1024) with 1023.
              specialize (Z_mod_lt (Int.unsigned i/PgSize) one_k).
              omega.
            }
            inv HP; try rewrite <- H9 in HLoad; try rewrite <- H5 in HLoad; contra_inv.
            pose proof relate_PMap_re as HPP.
            inv HPP. specialize (H9 _ valid_PT´ _ HI pi pdx).
            rewrite H5 in H9. specialize (H9 refl_equal _ HI1).
            destruct H9 as [v1[HLD1 HP]].
            rewrite Int.unsigned_repr; [|rewrite_omega].
            rewrite HLD, H7.
            rewrite Z_div_plus_full_l; [|omega].
            rewrite (Zdiv_small PT_PERM_PTU); [|omega].
            rewrite Z.add_0_r. rewrite HLD1. clear HLD1.
            destruct (zle (Int.unsigned i mod 4096) (4096 - size_chunk chunk)); contra_inv.
            destruct (Zdivide_dec (align_chunk chunk) (Int.unsigned i mod 4096)
                                  (Memdata.align_chunk_pos chunk)); contra_inv.
            inv HP; try rewrite <- H11 in HLoad; contra_inv.
            {
              change (Int.unsigned Int.zero mod 4096) with 0; simpl.
              eapply pagefault_correct; eauto.
            }
            {
              rewrite <- H9 in HLoad; contra_inv. rewrite H12.
              assert (HW1: (padr × PgSize + v) mod PgSize = v mod PgSize).
              {
                rewrite Zplus_mod.
                rewrite Z_mod_mult.
                rewrite Z.add_0_l.
                apply Zmod_mod.
              }
              assert (HW2: (padr × PgSize + v) / PgSize = padr).
              {
                rewrite Z_div_plus_full_l; [|omega].
                rewrite (Zdiv_small v). omega.
                functional inversion H11; subst; omega.
              }
              rewrite HW1, HW2.
              functional inversion H11; rewrite <- H13 in HLoad; contra_inv;
              (rewrite Zmod_small; trivial; [|omega]; simpl;
               eapply exec_flatmem_store_correct; eauto).
              apply PTADDR_mod_lt. assumption.
              apply PTADDR_mod_lt. assumption.
            }
        +
          eapply guest_intel_store_correct1; eauto.
      -
        inv HW; subdestruct; eapply storel_correct; eauto.
    Qed.

  End WITHMEM.

End Refinement.