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Proofreading and Coq-version-updating AbstractInterpretation
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1 changed files with 31 additions and 31 deletions
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@ -15,7 +15,7 @@ Set Implicit Arguments.
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* technique: abstract interpretation. *)
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(* Apologies for jumping right into abstract formal details, but that's what the
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* medium of Coq forces us on! We will apply abstract interpretation to the
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* medium of Coq forces on us! We will apply abstract interpretation to the
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* imperative language that we formalized in the last chapter. Here's a record
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* capturing the idea of an abstract interpretation for that language. *)
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Record absint := {
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@ -87,7 +87,7 @@ Definition absint_complete (a : absint) :=
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(* Let's ask [eauto] to try all of the above soundness rules automatically. *)
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Hint Resolve TopSound ConstSound AddSound SubtractSound MultiplySound
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AddMonotone SubtractMonotone MultiplyMonotone
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JoinSoundLeft JoinSoundRight.
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JoinSoundLeft JoinSoundRight : core.
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(** * Example: even-odd analysis *)
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@ -155,7 +155,7 @@ Proof.
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exists (x + 1); linear_arithmetic.
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Qed.
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Hint Resolve isEven_0 isEven_1 isEven_S_Even isEven_S_Odd.
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Hint Resolve isEven_0 isEven_1 isEven_S_Even isEven_S_Odd : core.
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(* END SPAN OF BORING THEOREMS ABOUT PARITY. *)
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@ -218,7 +218,7 @@ Inductive parity_rep : nat -> parity -> Prop :=
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| PrEither : forall n,
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parity_rep n Either.
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Hint Constructors parity_rep.
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Hint Constructors parity_rep : core.
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(* Putting it all together: *)
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Definition parity_absint := {|
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@ -242,7 +242,7 @@ Proof.
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invert IHn; eauto.
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Qed.
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Hint Resolve parity_const_sound.
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Hint Resolve parity_const_sound : core.
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Lemma even_not_odd :
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(forall n, parity_rep n Even -> parity_rep n Odd)
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@ -270,7 +270,7 @@ Proof.
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linear_arithmetic.
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Qed.
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Hint Resolve even_not_odd odd_not_even.
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Hint Resolve even_not_odd odd_not_even : core.
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Lemma parity_join_complete : forall n x y,
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parity_rep n (parity_join x y)
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@ -283,7 +283,7 @@ Proof.
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propositional; eauto using odd_notEven.
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Qed.
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Hint Resolve parity_join_complete.
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Hint Resolve parity_join_complete : core.
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(* The final proof uses some automation that we won't explain, to descend down
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* to the hearts of the interesting cases. *)
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@ -446,7 +446,7 @@ Inductive flow_insensitive_step a (c : cmd) : astate a -> astate a -> Prop :=
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(x, e) \in assignmentsOf c
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-> flow_insensitive_step c s (merge_astate s (s $+ (x, absint_interp e s))).
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Hint Constructors flow_insensitive_step.
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Hint Constructors flow_insensitive_step : core.
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Definition flow_insensitive_trsys a (s : astate a) (c : cmd) := {|
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Initial := {s};
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@ -477,7 +477,7 @@ Inductive Rinsensitive a (c : cmd) : valuation * cmd -> astate a -> Prop :=
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-> assignmentsOf c' \subseteq assignmentsOf c
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-> Rinsensitive c (v, c') s.
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Hint Constructors Rinsensitive.
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Hint Constructors Rinsensitive : core.
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(* A helpful decomposition property for compatibility *)
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Lemma insensitive_compatible_add : forall a (s : astate a) v x na n,
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@ -508,7 +508,7 @@ Proof.
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eauto.
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Qed.
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Hint Resolve insensitive_compatible_add absint_interp_ok.
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Hint Resolve insensitive_compatible_add absint_interp_ok : core.
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(* With that, let's show that the flow-insensitive version of a program
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* *simulates* the original program, w.r.t. any sound abstract
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@ -598,7 +598,7 @@ Proof.
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cases (s $? x); equality.
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Qed.
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Hint Resolve subsumed_refl.
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Hint Resolve subsumed_refl : core.
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Lemma subsumed_use : forall a (s s' : astate a) x n t0 t,
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s $? x = Some t0
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@ -626,7 +626,7 @@ Proof.
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equality.
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Qed.
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Hint Resolve subsumed_use subsumed_use_empty.
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Hint Resolve subsumed_use subsumed_use_empty : core.
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Lemma subsumed_trans : forall a (s1 s2 s3 : astate a),
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subsumed s1 s2
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@ -651,7 +651,7 @@ Proof.
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invert H0; eauto.
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Qed.
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Hint Resolve subsumed_merge_left.
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Hint Resolve subsumed_merge_left : core.
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Lemma subsumed_merge_both : forall a, absint_sound a
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-> absint_complete a
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@ -681,7 +681,7 @@ Proof.
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specialize (H0 x0); eauto.
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Qed.
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Hint Resolve subsumed_add.
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Hint Resolve subsumed_add : core.
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(* A key property of interpreting expressions abstractly: it's *monotone*, in
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* the sense that moving up to a less precise [astate] leads to a less precise
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@ -698,7 +698,7 @@ Proof.
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cases (s $? x); eauto.
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Qed.
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Hint Resolve absint_interp_monotone.
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Hint Resolve absint_interp_monotone : core.
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(* [runAllAssignments] also respects the subsumption order, in going from inputs
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* to outputs. *)
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@ -710,7 +710,7 @@ Proof.
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induct 2; simplify; eauto using subsumed_trans.
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Qed.
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Hint Resolve runAllAssignments_monotone.
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Hint Resolve runAllAssignments_monotone : core.
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(* The output of [runAllAssignments] subsumes every state reachable by running a
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* single command. *)
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@ -971,7 +971,7 @@ Proof.
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invert H1; eauto.
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Qed.
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Hint Resolve compatible_add.
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Hint Resolve compatible_add : core.
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(* A similar result follows about soundness of expression interpretation. *)
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Theorem absint_interp_ok2 : forall a, absint_sound a
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@ -989,7 +989,7 @@ Proof.
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assumption.
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Qed.
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Hint Resolve absint_interp_ok2.
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Hint Resolve absint_interp_ok2 : core.
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(* The new type of invariant we calculate as we go: a map from commands to
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* [astate]s. The idea is that we populate this map with the commands that show
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@ -1082,7 +1082,7 @@ Inductive abs_step a : astate a * cmd -> astate a * cmd -> Prop :=
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-> ss $? c' = Some s'
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-> abs_step (s, c) (s', c').
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Hint Constructors abs_step.
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Hint Constructors abs_step : core.
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Definition absint_trsys a (c : cmd) := {|
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Initial := {($0, c)};
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@ -1096,7 +1096,7 @@ Inductive Rabsint a : valuation * cmd -> astate a * cmd -> Prop :=
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compatible s v
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-> Rabsint (v, c) (s, c).
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Hint Constructors abs_step Rabsint.
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Hint Constructors abs_step Rabsint : core.
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Theorem absint_simulates : forall a v c,
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absint_sound a
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@ -1166,7 +1166,7 @@ Proof.
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unfold subsumeds; simplify; eauto.
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Qed.
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Hint Resolve subsumeds_refl.
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Hint Resolve subsumeds_refl : core.
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Lemma subsumeds_add : forall a (ss1 ss2 : astates a) c s1 s2,
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subsumeds ss1 ss2
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@ -1178,7 +1178,7 @@ Proof.
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invert H1; eauto.
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Qed.
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Hint Resolve subsumeds_add.
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Hint Resolve subsumeds_add : core.
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Lemma subsumeds_empty : forall a (ss : astates a),
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subsumeds $0 ss.
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@ -1200,7 +1200,7 @@ Qed.
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(* Now we just repeat [oneStepClosure] until finding a fixed point.
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* Note the arguments to this predicate, called like
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* [interpret ss worklist ss']. [ss] is the state we're starting from, and
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* [ss'] is the final invariatn we calculcate. [worklist] includes only those
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* [ss'] is the final invariant we calculate. [worklist] includes only those
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* command/[astate] pairs that we didn't already explore outward from. It would
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* be pointless to continually explore from all the points we already
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* processed! *)
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@ -1389,7 +1389,7 @@ Proof.
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simplify; cases y; equality.
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Qed.
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Hint Resolve merge_astates_fok_parity merge_astates_fok2_parity.
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Hint Resolve merge_astates_fok_parity merge_astates_fok2_parity : core.
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(* Our second corral of tactics for the day, automating iteration *)
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Ltac interpret_simpl := unfold merge_astates, merge_astate;
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@ -1590,7 +1590,7 @@ Record interval_rep (n : nat) (i : interval) : Prop := {
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end
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}.
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Hint Constructors interval_rep.
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Hint Constructors interval_rep : core.
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(* Test if an interval contains any values. *)
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Definition impossible (x : interval) :=
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@ -1603,7 +1603,7 @@ Definition impossible (x : interval) :=
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* Otherwise, we might join an impossible interval with a possible interval and
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* get a different, less precise possible interval, which can't be the *least*
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* upper bound of the two. Rather, that least bound would need to be the
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* original possible interval. Similary, without this check, we could join two
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* original possible interval. Similarly, without this check, we could join two
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* impossible intervals and get a possible interval, when the least upper bound
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* must be impossible. *)
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Definition interval_join (x y : interval) :=
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@ -1760,7 +1760,7 @@ Definition interval_absint := {|
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Represents := interval_rep
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|}.
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Hint Resolve mult_le_compat. (* Theorem from Coq standard library *)
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Hint Resolve mult_le_compat : core. (* Theorem from Coq standard library *)
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(* When one interval implies another, and the first is possible, we can deduce
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* arithmetic relationships betwen their respective bounds. *)
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@ -1859,7 +1859,7 @@ Proof.
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transitivity (a' * b'); eauto.
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Qed.
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Hint Immediate mult_bound1 mult_bound2.
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Hint Immediate mult_bound1 mult_bound2 : core.
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(* Now a bruiser of an automated proof, covering all the cases to show that this
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* abstraction is sound. *)
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@ -1914,10 +1914,10 @@ Proof.
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simplify; cases y; equality.
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Qed.
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Hint Resolve merge_astates_fok_interval merge_astates_fok2_interval.
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Hint Resolve merge_astates_fok_interval merge_astates_fok2_interval : core.
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(* The same kind of lemma we've proved for finishing off each proof by abstract
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* interpretation so far. *)
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* interpretation so far *)
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Lemma final_upper : forall (s s' : astate interval_absint) v x l u,
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compatible s v
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-> subsumed s s'
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@ -2109,7 +2109,7 @@ Proof.
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simplify; cases y; equality.
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Qed.
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Hint Resolve merge_astates_fok_interval_widening merge_astates_fok2_interval_widening.
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Hint Resolve merge_astates_fok_interval_widening merge_astates_fok2_interval_widening : core.
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Lemma final_lower_widening : forall (s s' : astate interval_absint_widening) v x l,
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compatible s v
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