diff options
Diffstat (limited to 'kernel/uGraph.ml')
| -rw-r--r-- | kernel/uGraph.ml | 147 |
1 files changed, 121 insertions, 26 deletions
diff --git a/kernel/uGraph.ml b/kernel/uGraph.ml index 487257a776..bc624ba56d 100644 --- a/kernel/uGraph.ml +++ b/kernel/uGraph.ml @@ -1,9 +1,11 @@ (************************************************************************) -(* v * The Coq Proof Assistant / The Coq Development Team *) -(* <O___,, * INRIA - CNRS - LIX - LRI - PPS - Copyright 1999-2015 *) +(* * The Coq Proof Assistant / The Coq Development Team *) +(* v * INRIA, CNRS and contributors - Copyright 1999-2018 *) +(* <O___,, * (see CREDITS file for the list of authors) *) (* \VV/ **************************************************************) -(* // * This file is distributed under the terms of the *) -(* * GNU Lesser General Public License Version 2.1 *) +(* // * This file is distributed under the terms of the *) +(* * GNU Lesser General Public License Version 2.1 *) +(* * (see LICENSE file for the text of the license) *) (************************************************************************) open Pp @@ -19,7 +21,7 @@ open Univ (* Revisions by Bruno Barras, Hugo Herbelin, Pierre Letouzey, Matthieu Sozeau, Pierre-Marie Pédrot, Jacques-Henri Jourdan *) -let error_inconsistency o u v (p:explanation option) = +let error_inconsistency o u v p = raise (UniverseInconsistency (o,Universe.make u,Universe.make v,p)) (* Universes are stratified by a partial ordering $\le$. @@ -501,7 +503,7 @@ let insert_edge strict ucan vcan g = let () = cleanup_universes g in raise e -let add_universe vlev strict g = +let add_universe_gen vlev g = try let _arcv = UMap.find vlev g.entries in raise AlreadyDeclared @@ -518,8 +520,14 @@ let add_universe vlev strict g = } in let entries = UMap.add vlev (Canonical v) g.entries in - let g = { entries; index = g.index - 1; n_nodes = g.n_nodes + 1; n_edges = g.n_edges } in - insert_edge strict (get_set_arc g) v g + { entries; index = g.index - 1; n_nodes = g.n_nodes + 1; n_edges = g.n_edges }, v + +let add_universe vlev strict g = + let g, v = add_universe_gen vlev g in + insert_edge strict (get_set_arc g) v g + +let add_universe_unconstrained vlev g = + fst (add_universe_gen vlev g) exception Found_explanation of explanation @@ -555,8 +563,7 @@ let get_explanation strict u v g = else match traverse strict u with Some exp -> exp | None -> assert false let get_explanation strict u v g = - if !Flags.univ_print then Some (get_explanation strict u v g) - else None + Some (lazy (get_explanation strict u v g)) (* To compare two nodes, we simply do a forward search. We implement two improvements: @@ -695,6 +702,9 @@ let enforce_univ_lt u v g = error_inconsistency Lt u v (get_explanation false v u g) let empty_universes = + { entries = UMap.empty; index = 0; n_nodes = 0; n_edges = 0 } + +let initial_universes = let set_arc = Canonical { univ = Level.set; ltle = LMap.empty; @@ -717,9 +727,6 @@ let empty_universes = let empty = { entries; index = (-2); n_nodes = 2; n_edges = 0 } in enforce_univ_lt Level.prop Level.set empty -(* Prop = Set is forbidden here. *) -let initial_universes = empty_universes - let is_initial_universes g = UMap.equal (==) g.entries initial_universes.entries let enforce_constraint cst g = @@ -740,6 +747,45 @@ let check_constraint g (l,d,r) = let check_constraints c g = Constraint.for_all (check_constraint g) c +let leq_expr (u,m) (v,n) = + let d = match m - n with + | 1 -> Lt + | diff -> assert (diff <= 0); Le + in + (u,d,v) + +let enforce_leq_alg u v g = + let enforce_one (u,v) = function + | Inr _ as orig -> orig + | Inl (cstrs,g) as orig -> + if check_smaller_expr g u v then orig + else + (let c = leq_expr u v in + match enforce_constraint c g with + | g -> Inl (Constraint.add c cstrs,g) + | exception (UniverseInconsistency _ as e) -> Inr e) + in + (* max(us) <= max(vs) <-> forall u in us, exists v in vs, u <= v *) + let c = Universe.map (fun u -> Universe.map (fun v -> (u,v)) v) u in + let c = List.cartesians enforce_one (Inl (Constraint.empty,g)) c in + (* We pick a best constraint: smallest number of constraints, not an error if possible. *) + let order x y = match x, y with + | Inr _, Inr _ -> 0 + | Inl _, Inr _ -> -1 + | Inr _, Inl _ -> 1 + | Inl (c,_), Inl (c',_) -> + Int.compare (Constraint.cardinal c) (Constraint.cardinal c') + in + match List.min order c with + | Inl x -> x + | Inr e -> raise e + +(* sanity check wrapper *) +let enforce_leq_alg u v g = + let _,g as cg = enforce_leq_alg u v g in + assert (check_leq g u v); + cg + (* Normalization *) (** [normalize_universes g] returns a graph where all edges point @@ -766,18 +812,54 @@ let normalize_universes g = g.entries g let constraints_of_universes g = + let module UF = Unionfind.Make (LSet) (LMap) in + let uf = UF.create () in let constraints_of u v acc = match v with | Canonical {univ=u; ltle} -> UMap.fold (fun v strict acc-> let typ = if strict then Lt else Le in Constraint.add (u,typ,v) acc) ltle acc - | Equiv v -> Constraint.add (u,Eq,v) acc + | Equiv v -> UF.union u v uf; acc in - UMap.fold constraints_of g.entries Constraint.empty - -let constraints_of_universes g = - constraints_of_universes (normalize_universes g) + let csts = UMap.fold constraints_of g.entries Constraint.empty in + csts, UF.partition uf + +(* domain g.entries = kept + removed *) +let constraints_for ~kept g = + (* rmap: partial map from canonical universes to kept universes *) + let rmap, csts = LSet.fold (fun u (rmap,csts) -> + let arcu = repr g u in + if LSet.mem arcu.univ kept then + LMap.add arcu.univ arcu.univ rmap, enforce_eq_level u arcu.univ csts + else + match LMap.find arcu.univ rmap with + | v -> rmap, enforce_eq_level u v csts + | exception Not_found -> LMap.add arcu.univ u rmap, csts) + kept (LMap.empty,Constraint.empty) + in + let rec add_from u csts todo = match todo with + | [] -> csts + | (v,strict)::todo -> + let v = repr g v in + (match LMap.find v.univ rmap with + | v -> + let d = if strict then Lt else Le in + let csts = Constraint.add (u,d,v) csts in + add_from u csts todo + | exception Not_found -> + (* v is not equal to any kept universe *) + let todo = LMap.fold (fun v' strict' todo -> + (v',strict || strict') :: todo) + v.ltle todo + in + add_from u csts todo) + in + LSet.fold (fun u csts -> + let arc = repr g u in + LMap.fold (fun v strict csts -> add_from u csts [v,strict]) + arc.ltle csts) + kept csts (** [sort_universes g] builds a totally ordered universe graph. The output graph should imply the input graph (and the implication @@ -830,6 +912,18 @@ let sort_universes g = in normalize_universes g +(** Subtyping of polymorphic contexts *) + +let check_subtype univs ctxT ctx = + if AUContext.size ctxT == AUContext.size ctx then + let (inst, cst) = UContext.dest (AUContext.repr ctx) in + let cstT = UContext.constraints (AUContext.repr ctxT) in + let push accu v = add_universe v false accu in + let univs = Array.fold_left push univs (Instance.to_array inst) in + let univs = merge_constraints cstT univs in + check_constraints cst univs + else false + (** Instances *) let check_eq_instances g t1 t2 = @@ -878,23 +972,24 @@ let dump_universes output g = let merge_constraints = if Flags.profile then - let key = Profile.declare_profile "merge_constraints" in - Profile.profile2 key merge_constraints + let key = CProfile.declare_profile "merge_constraints" in + CProfile.profile2 key merge_constraints else merge_constraints let check_constraints = if Flags.profile then - let key = Profile.declare_profile "check_constraints" in - Profile.profile2 key check_constraints + let key = CProfile.declare_profile "check_constraints" in + CProfile.profile2 key check_constraints else check_constraints let check_eq = if Flags.profile then - let check_eq_key = Profile.declare_profile "check_eq" in - Profile.profile3 check_eq_key check_eq + let check_eq_key = CProfile.declare_profile "check_eq" in + CProfile.profile3 check_eq_key check_eq else check_eq let check_leq = if Flags.profile then - let check_leq_key = Profile.declare_profile "check_leq" in - Profile.profile3 check_leq_key check_leq + let check_leq_key = CProfile.declare_profile "check_leq" in + CProfile.profile3 check_leq_key check_leq else check_leq + |