ziv@2235: structure Sqlcache (* DEBUG: add back :> SQLCACHE. *) = struct
ziv@2209: 
ziv@2209: open Mono
ziv@2209: 
ziv@2209: structure IS = IntBinarySet
ziv@2209: structure IM = IntBinaryMap
ziv@2213: structure SK = struct type ord_key = string val compare = String.compare end
ziv@2213: structure SS = BinarySetFn(SK)
ziv@2213: structure SM = BinaryMapFn(SK)
ziv@2213: structure SIMM = MultimapFn(structure KeyMap = SM structure ValSet = IS)
ziv@2209: 
ziv@2216: (* Filled in by [cacheWrap] during [Sqlcache]. *)
ziv@2213: val ffiInfo : {index : int, params : int} list ref = ref []
ziv@2209: 
ziv@2227: fun resetFfiInfo () = ffiInfo := []
ziv@2227: 
ziv@2213: fun getFfiInfo () = !ffiInfo
ziv@2213: 
ziv@2215: (* Some FFIs have writing as their only effect, which the caching records. *)
ziv@2215: val ffiEffectful =
ziv@2223:     (* ASK: how can this be less hard-coded? *)
ziv@2215:     let
ziv@2215:         val fs = SS.fromList ["htmlifyInt_w",
ziv@2215:                               "htmlifyFloat_w",
ziv@2215:                               "htmlifyString_w",
ziv@2215:                               "htmlifyBool_w",
ziv@2215:                               "htmlifyTime_w",
ziv@2215:                               "attrifyInt_w",
ziv@2215:                               "attrifyFloat_w",
ziv@2215:                               "attrifyString_w",
ziv@2215:                               "attrifyChar_w",
ziv@2215:                               "urlifyInt_w",
ziv@2215:                               "urlifyFloat_w",
ziv@2215:                               "urlifyString_w",
ziv@2215:                               "urlifyBool_w",
ziv@2215:                               "urlifyChannel_w"]
ziv@2215:     in
ziv@2215:         fn (m, f) => Settings.isEffectful (m, f)
ziv@2215:                      andalso not (m = "Basis" andalso SS.member (fs, f))
ziv@2215:     end
ziv@2215: 
ziv@2234: val cache = ref LruCache.cache
ziv@2233: fun setCache c = cache := c
ziv@2233: fun getCache () = !cache
ziv@2233: 
ziv@2215: 
ziv@2215: (* Effect analysis. *)
ziv@2215: 
ziv@2216: (* Makes an exception for [EWrite] (which is recorded when caching). *)
ziv@2230: fun effectful doPrint (effs : IS.set) (inFunction : bool) (bound : int) : exp -> bool =
ziv@2215:     (* If result is true, expression is definitely effectful. If result is
ziv@2215:        false, then expression is definitely not effectful if effs is fully
ziv@2215:        populated. The intended pattern is to use this a number of times equal
ziv@2215:        to the number of declarations in a file, Bellman-Ford style. *)
ziv@2234:     (* TODO: make incrementing of the number of bound variables cleaner,
ziv@2234:        probably by using [MonoUtil] instead of all this. *)
ziv@2215:     let
ziv@2215:         (* DEBUG: remove printing when done. *)
ziv@2215:         fun tru msg = if doPrint then (print (msg ^ "\n"); true) else true
ziv@2215:         val rec eff' =
ziv@2215:          (* ASK: is there a better way? *)
ziv@2215:          fn EPrim _ => false
ziv@2215:           (* We don't know if local functions have effects when applied. *)
ziv@2215:           | ERel idx => if inFunction andalso idx >= bound
ziv@2215:                         then tru ("rel" ^ Int.toString idx) else false
ziv@2215:           | ENamed name => if IS.member (effs, name) then tru "named" else false
ziv@2215:           | ECon (_, _, NONE) => false
ziv@2215:           | ECon (_, _, SOME e) => eff e
ziv@2215:           | ENone _ => false
ziv@2215:           | ESome (_, e) => eff e
ziv@2215:           | EFfi (m, f) => if ffiEffectful (m, f) then tru "ffi" else false
ziv@2215:           | EFfiApp (m, f, _) => if ffiEffectful (m, f) then tru "ffiapp" else false
ziv@2215:           (* ASK: we're calling functions effectful if they have effects when
ziv@2215:              applied or if the function expressions themselves have effects.
ziv@2215:              Is that okay? *)
ziv@2215:           (* This is okay because the values we ultimately care about aren't
ziv@2215:              functions, and this is a conservative approximation, anyway. *)
ziv@2215:           | EApp (eFun, eArg) => effectful doPrint effs true bound eFun orelse eff eArg
ziv@2215:           | EAbs (_, _, _, e) => effectful doPrint effs inFunction (bound+1) e
ziv@2215:           | EUnop (_, e) => eff e
ziv@2215:           | EBinop (_, _, e1, e2) => eff e1 orelse eff e2
ziv@2215:           | ERecord xs => List.exists (fn (_, e, _) => eff e) xs
ziv@2215:           | EField (e, _) => eff e
ziv@2215:           (* If any case could be effectful, consider it effectful. *)
ziv@2215:           | ECase (e, xs, _) => eff e orelse List.exists (fn (_, e) => eff e) xs
ziv@2215:           | EStrcat (e1, e2) => eff e1 orelse eff e2
ziv@2215:           (* ASK: how should we treat these three? *)
ziv@2215:           | EError _ => tru "error"
ziv@2215:           | EReturnBlob _ => tru "blob"
ziv@2215:           | ERedirect _ => tru "redirect"
ziv@2215:           (* EWrite is a special exception because we record writes when caching. *)
ziv@2215:           | EWrite _ => false
ziv@2215:           | ESeq (e1, e2) => eff e1 orelse eff e2
ziv@2215:           (* TODO: keep context of which local variables aren't effectful? Only
ziv@2215:              makes a difference for function expressions, though. *)
ziv@2215:           | ELet (_, _, eBind, eBody) => eff eBind orelse
ziv@2215:                                          effectful doPrint effs inFunction (bound+1) eBody
ziv@2215:           | EClosure (_, es) => List.exists eff es
ziv@2215:           (* TODO: deal with EQuery. *)
ziv@2215:           | EQuery _ => tru "query"
ziv@2215:           | EDml _ => tru "dml"
ziv@2215:           | ENextval _ => tru "nextval"
ziv@2215:           | ESetval _ => tru "setval"
ziv@2215:           | EUnurlify (e, _, _) => eff e
ziv@2215:           (* ASK: how should we treat this? *)
ziv@2215:           | EJavaScript _ => tru "javascript"
ziv@2215:           (* ASK: these are all effectful, right? *)
ziv@2215:           | ESignalReturn _ => tru "signalreturn"
ziv@2215:           | ESignalBind _ => tru "signalbind"
ziv@2215:           | ESignalSource _ => tru "signalsource"
ziv@2215:           | EServerCall _ => tru "servercall"
ziv@2215:           | ERecv _ => tru "recv"
ziv@2215:           | ESleep _ => tru "sleep"
ziv@2215:           | ESpawn _ => tru "spawn"
ziv@2215:         and eff = fn (e', _) => eff' e'
ziv@2215:     in
ziv@2215:         eff
ziv@2215:     end
ziv@2215: 
ziv@2215: (* TODO: test this. *)
ziv@2215: val effectfulMap =
ziv@2215:     let
ziv@2215:         fun doVal ((_, name, _, e, _), effMap) =
ziv@2215:             if effectful false effMap false 0 e
ziv@2215:             then IS.add (effMap, name)
ziv@2215:             else effMap
ziv@2215:         val doDecl =
ziv@2215:          fn (DVal v, effMap) => doVal (v, effMap)
ziv@2215:           (* Repeat the list of declarations a number of times equal to its size. *)
ziv@2215:           | (DValRec vs, effMap) =>
ziv@2215:             List.foldl doVal effMap (List.concat (List.map (fn _ => vs) vs))
ziv@2215:           (* ASK: any other cases? *)
ziv@2215:           | (_, effMap) => effMap
ziv@2215:     in
ziv@2215:         MonoUtil.File.fold {typ = #2, exp = #2, decl = doDecl} IS.empty
ziv@2215:     end
ziv@2215: 
ziv@2215: 
ziv@2216: (* Boolean formula normalization. *)
ziv@2216: 
ziv@2234: datatype junctionType = Conj | Disj
ziv@2216: 
ziv@2216: datatype 'atom formula =
ziv@2216:          Atom of 'atom
ziv@2216:        | Negate of 'atom formula
ziv@2234:        | Combo of junctionType * 'atom formula list
ziv@2216: 
ziv@2234: val flipJt = fn Conj => Disj | Disj => Conj
ziv@2216: 
ziv@2235: fun listBind xs f = List.concat (map f xs)
ziv@2216: 
ziv@2216: val rec cartesianProduct : 'a list list -> 'a list list =
ziv@2216:  fn [] => [[]]
ziv@2235:   | (xs :: xss) => listBind (cartesianProduct xss)
ziv@2235:                             (fn ys => listBind xs (fn x => [x :: ys]))
ziv@2216: 
ziv@2218: (* Pushes all negation to the atoms.*)
ziv@2218: fun pushNegate (negate : 'atom -> 'atom) (negating : bool) =
ziv@2218:  fn Atom x => Atom (if negating then negate x else x)
ziv@2218:   | Negate f => pushNegate negate (not negating) f
ziv@2234:   | Combo (n, fs) => Combo (if negating then flipJt n else n, map (pushNegate negate negating) fs)
ziv@2218: 
ziv@2218: val rec flatten =
ziv@2235:  fn Combo (_, [f]) => flatten f
ziv@2235:   | Combo (j, fs) =>
ziv@2235:     Combo (j, List.foldr (fn (f, acc) =>
ziv@2218:                              case f of
ziv@2235:                                  Combo (j', fs') =>
ziv@2235:                                  if j = j' orelse length fs' = 1
ziv@2235:                                  then fs' @ acc
ziv@2235:                                  else f :: acc
ziv@2218:                                | _ => f :: acc)
ziv@2218:                          []
ziv@2218:                          (map flatten fs))
ziv@2218:   | f => f
ziv@2218: 
ziv@2235: fun normalize' ((simplifyLists, simplifyAtomsConj, simplifyAtomsDisj, negate)
ziv@2235:                 : ('a list list -> 'a list list)
ziv@2235:                   * ('a list -> 'a list)
ziv@2235:                   * ('a list -> 'a list)
ziv@2235:                   * ('a -> 'a))
ziv@2235:                (junc : junctionType) =
ziv@2216:     let
ziv@2235:         fun simplify junc = simplifyLists o map (case junc of
ziv@2235:                                                      Conj => simplifyAtomsConj
ziv@2235:                                                    | Disj => simplifyAtomsDisj)
ziv@2235:         fun norm junc =
ziv@2235:             simplify junc
ziv@2235:             o (fn Atom x => [[x]]
ziv@2235:                 | Negate f => map (map negate) (norm (flipJt junc) f)
ziv@2235:                 | Combo (j, fs) =>
ziv@2235:                   let
ziv@2235:                       val fss = listBind fs (norm j)
ziv@2235:                   in
ziv@2235:                       if j = junc then fss else cartesianProduct fss
ziv@2235:                   end)
ziv@2216:     in
ziv@2235:         norm junc
ziv@2216:     end
ziv@2216: 
ziv@2235: fun normalize (simplifyLists, simplifyAtomsConj, simplifyAtomsDisj, negate, junc) =
ziv@2235:     (normalize' (simplifyLists, simplifyAtomsConj, simplifyAtomsDisj, negate) junc)
ziv@2235:     o flatten
ziv@2235:     o pushNegate negate false
ziv@2216: 
ziv@2221: fun mapFormula mf =
ziv@2221:  fn Atom x => Atom (mf x)
ziv@2221:   | Negate f => Negate (mapFormula mf f)
ziv@2235:   | Combo (j, fs) => Combo (j, map (mapFormula mf) fs)
ziv@2216: 
ziv@2230: 
ziv@2215: (* SQL analysis. *)
ziv@2213: 
ziv@2235: structure CmpKey : ORD_KEY = struct
ziv@2235: 
ziv@2235:     type ord_key = Sql.cmp
ziv@2235: 
ziv@2235:     val compare =
ziv@2235:      fn (Sql.Eq, Sql.Eq) => EQUAL
ziv@2235:       | (Sql.Eq, _) => LESS
ziv@2235:       | (_, Sql.Eq) => GREATER
ziv@2235:       | (Sql.Ne, Sql.Ne) => EQUAL
ziv@2235:       | (Sql.Ne, _) => LESS
ziv@2235:       | (_, Sql.Ne) => GREATER
ziv@2235:       | (Sql.Lt, Sql.Lt) => EQUAL
ziv@2235:       | (Sql.Lt, _) => LESS
ziv@2235:       | (_, Sql.Lt) => GREATER
ziv@2235:       | (Sql.Le, Sql.Le) => EQUAL
ziv@2235:       | (Sql.Le, _) => LESS
ziv@2235:       | (_, Sql.Le) => GREATER
ziv@2235:       | (Sql.Gt, Sql.Gt) => EQUAL
ziv@2235:       | (Sql.Gt, _) => LESS
ziv@2235:       | (_, Sql.Gt) => GREATER
ziv@2235:       | (Sql.Ge, Sql.Ge) => EQUAL
ziv@2235: 
ziv@2235: end
ziv@2235: 
ziv@2235: 
ziv@2235: functor ListKeyFn (K : ORD_KEY) : ORD_KEY = struct
ziv@2235: 
ziv@2235:     type ord_key = K.ord_key list
ziv@2235: 
ziv@2235:     val rec compare =
ziv@2235:      fn ([], []) => EQUAL
ziv@2235:       | ([], _) => LESS
ziv@2235:       | (_, []) => GREATER
ziv@2235:       | (x :: xs, y :: ys) => (case K.compare (x, y) of
ziv@2235:                                    EQUAL => compare (xs, ys)
ziv@2235:                                  | ord => ord)
ziv@2235: 
ziv@2235: end
ziv@2235: 
ziv@2235: functor OptionKeyFn (K : ORD_KEY) : ORD_KEY = struct
ziv@2235: 
ziv@2235:     type ord_key = K.ord_key option
ziv@2235: 
ziv@2235:     val compare =
ziv@2235:      fn (NONE, NONE) => EQUAL
ziv@2235:       | (NONE, _) => LESS
ziv@2235:       | (_, NONE) => GREATER
ziv@2235:       | (SOME x, SOME y) => K.compare (x, y)
ziv@2235: 
ziv@2235: end
ziv@2235: 
ziv@2235: functor TripleKeyFn (structure I : ORD_KEY
ziv@2235:                      structure J : ORD_KEY
ziv@2235:                      structure K : ORD_KEY)
ziv@2235:         : ORD_KEY where type ord_key = I.ord_key * J.ord_key * K.ord_key = struct
ziv@2235: 
ziv@2235:     type ord_key = I.ord_key * J.ord_key * K.ord_key
ziv@2235: 
ziv@2235:     fun compare ((i1, j1, k1), (i2, j2, k2)) =
ziv@2235:         case I.compare (i1, i2) of
ziv@2235:             EQUAL => (case J.compare (j1, j2) of
ziv@2235:                           EQUAL => K.compare (k1, k2)
ziv@2235:                         | ord => ord)
ziv@2235:           | ord => ord
ziv@2235: 
ziv@2235: end
ziv@2235: 
ziv@2216: val rec chooseTwos : 'a list -> ('a * 'a) list =
ziv@2216:  fn [] => []
ziv@2216:   | x :: ys => map (fn y => (x, y)) ys @ chooseTwos ys
ziv@2213: 
ziv@2216: datatype atomExp =
ziv@2216:          QueryArg of int
ziv@2216:        | DmlRel of int
ziv@2216:        | Prim of Prim.t
ziv@2216:        | Field of string * string
ziv@2216: 
ziv@2216: structure AtomExpKey : ORD_KEY = struct
ziv@2216: 
ziv@2234:     type ord_key = atomExp
ziv@2216: 
ziv@2234:     val compare =
ziv@2234:      fn (QueryArg n1, QueryArg n2) => Int.compare (n1, n2)
ziv@2234:       | (QueryArg _, _) => LESS
ziv@2234:       | (_, QueryArg _) => GREATER
ziv@2234:       | (DmlRel n1, DmlRel n2) => Int.compare (n1, n2)
ziv@2234:       | (DmlRel _, _) => LESS
ziv@2234:       | (_, DmlRel _) => GREATER
ziv@2234:       | (Prim p1, Prim p2) => Prim.compare (p1, p2)
ziv@2234:       | (Prim _, _) => LESS
ziv@2234:       | (_, Prim _) => GREATER
ziv@2234:       | (Field (t1, f1), Field (t2, f2)) =>
ziv@2234:         case String.compare (t1, t2) of
ziv@2234:             EQUAL => String.compare (f1, f2)
ziv@2234:           | ord => ord
ziv@2216: 
ziv@2216: end
ziv@2216: 
ziv@2216: structure UF = UnionFindFn(AtomExpKey)
ziv@2234: 
ziv@2235: structure ConflictMaps = struct
ziv@2235: 
ziv@2235:     structure TK = TripleKeyFn(structure I = CmpKey
ziv@2235:                                structure J = OptionKeyFn(AtomExpKey)
ziv@2235:                                structure K = OptionKeyFn(AtomExpKey))
ziv@2235:     structure TS = BinarySetFn(TK)
ziv@2235:     structure TLS = BinarySetFn(ListKeyFn(TK))
ziv@2235: 
ziv@2235:     val toKnownEquality =
ziv@2235:      (* [NONE] here means unkown. Anything that isn't a comparison between two
ziv@2235:         knowns shouldn't be used, and simply dropping unused terms is okay in
ziv@2235:         disjunctive normal form. *)
ziv@2235:      fn (Sql.Eq, SOME e1, SOME e2) => SOME (e1, e2)
ziv@2235:       | _ => NONE
ziv@2235: 
ziv@2235:     val equivClasses : (Sql.cmp * atomExp option * atomExp option) list -> atomExp list list =
ziv@2235:         UF.classes
ziv@2235:         o List.foldl UF.union' UF.empty
ziv@2235:         o List.mapPartial toKnownEquality
ziv@2235: 
ziv@2235:     fun addToEqs (eqs, n, e) =
ziv@2235:         case IM.find (eqs, n) of
ziv@2235:             (* Comparing to a constant is probably better than comparing to a
ziv@2235:                variable? Checking that existing constants match a new ones is
ziv@2235:                handled by [accumulateEqs]. *)
ziv@2235:             SOME (Prim _) => eqs
ziv@2235:           | _ => IM.insert (eqs, n, e)
ziv@2235: 
ziv@2235:     val accumulateEqs =
ziv@2235:      (* [NONE] means we have a contradiction. *)
ziv@2235:      fn (_, NONE) => NONE
ziv@2235:       | ((Prim p1, Prim p2), eqso) =>
ziv@2235:         (case Prim.compare (p1, p2) of
ziv@2235:              EQUAL => eqso
ziv@2235:            | _ => NONE)
ziv@2235:       | ((QueryArg n, Prim p), SOME eqs) => SOME (addToEqs (eqs, n, Prim p))
ziv@2235:       | ((QueryArg n, DmlRel r), SOME eqs) => SOME (addToEqs (eqs, n, DmlRel r))
ziv@2235:       | ((Prim p, QueryArg n), SOME eqs) => SOME (addToEqs (eqs, n, Prim p))
ziv@2235:       | ((DmlRel r, QueryArg n), SOME eqs) => SOME (addToEqs (eqs, n, DmlRel r))
ziv@2235:       (* TODO: deal with equalities between [DmlRel]s and [Prim]s.
ziv@2235:          This would involve guarding the invalidation with a check for the
ziv@2235:          relevant comparisons. *)
ziv@2235:       (* DEBUG: remove these print statements. *)
ziv@2235:       (* | ((DmlRel r, Prim p), eqso) => (print ("sadness " ^ Int.toString r ^ " = " ^ Prim.toString p ^ "\n"); eqso) *)
ziv@2235:       (* | ((Prim p, DmlRel r), eqso) => (print ("sadness " ^ Int.toString r ^ " = " ^ Prim.toString p ^ "\n"); eqso) *)
ziv@2235:       | (_, eqso) => eqso
ziv@2235: 
ziv@2235:     val eqsOfClass : atomExp list -> atomExp IM.map option =
ziv@2235:         List.foldl accumulateEqs (SOME IM.empty)
ziv@2235:         o chooseTwos
ziv@2235: 
ziv@2235:     fun toAtomExps rel (cmp, e1, e2) =
ziv@2235:         let
ziv@2235:             val qa =
ziv@2235:              (* Here [NONE] means unkown. *)
ziv@2235:              fn Sql.SqConst p => SOME (Prim p)
ziv@2235:               | Sql.Field tf => SOME (Field tf)
ziv@2235:               | Sql.Inj (EPrim p, _) => SOME (Prim p)
ziv@2235:               | Sql.Inj (ERel n, _) => SOME (rel n)
ziv@2235:               (* We can't deal with anything else, e.g., CURRENT_TIMESTAMP
ziv@2235:                  becomes Sql.Unmodeled, which becomes NONE here. *)
ziv@2235:               | _ => NONE
ziv@2235:         in
ziv@2235:             (cmp, qa e1, qa e2)
ziv@2235:         end
ziv@2235: 
ziv@2235:     fun negateCmp (cmp, e1, e2) =
ziv@2235:         (case cmp of
ziv@2235:              Sql.Eq => Sql.Ne
ziv@2235:            | Sql.Ne => Sql.Eq
ziv@2235:            | Sql.Lt => Sql.Ge
ziv@2235:            | Sql.Le => Sql.Gt
ziv@2235:            | Sql.Gt => Sql.Le
ziv@2235:            | Sql.Ge => Sql.Lt,
ziv@2235:          e1, e2)
ziv@2235: 
ziv@2235:     val markQuery : (Sql.cmp * Sql.sqexp * Sql.sqexp) formula ->
ziv@2235:                     (Sql.cmp * atomExp option * atomExp option) formula =
ziv@2235:         mapFormula (toAtomExps QueryArg)
ziv@2235: 
ziv@2235:     val markDml : (Sql.cmp * Sql.sqexp * Sql.sqexp) formula ->
ziv@2235:                   (Sql.cmp * atomExp option * atomExp option) formula =
ziv@2235:         mapFormula (toAtomExps DmlRel)
ziv@2235:     (* No eqs should have key conflicts because no variable is in two
ziv@2235:        equivalence classes, so the [#1] could be [#2]. *)
ziv@2235: 
ziv@2235:     val mergeEqs : (atomExp IntBinaryMap.map option list
ziv@2235:                     -> atomExp IntBinaryMap.map option) =
ziv@2235:         List.foldr (fn (SOME eqs, SOME acc) => SOME (IM.unionWith #1 (eqs, acc)) | _ => NONE)
ziv@2235:                    (SOME IM.empty)
ziv@2235: 
ziv@2235:     fun dnf (fQuery, fDml) =
ziv@2235:         let
ziv@2235:             val isStar =
ziv@2235:              (* TODO: decide if this is okay and, if so, factor out magic
ziv@2235:                 string "*" to a common location. *)
ziv@2235:              (* First guess: definitely okay for conservative approximation,
ziv@2235:                 though information lost might be useful even in current
ziv@2235:                 implementation for finding an extra equality. *)
ziv@2235:              fn SOME (Field (_, field)) => String.isSuffix "*" field
ziv@2235:               | _ => false
ziv@2235:             fun canIgnore (_, a1, a2) = isStar a1 orelse isStar a2
ziv@2235:             fun simplifyLists xs = TLS.listItems (TLS.addList (TLS.empty, xs))
ziv@2235:             fun simplifyAtomsConj xs = TS.listItems (TS.addList (TS.empty, xs))
ziv@2235:             val simplifyAtomsDisj = simplifyAtomsConj o List.filter canIgnore
ziv@2235:         in
ziv@2235:             normalize (simplifyLists, simplifyAtomsConj, simplifyAtomsDisj, negateCmp, Disj)
ziv@2235:                       (Combo (Conj, [markQuery fQuery, markDml fDml]))
ziv@2235:         end
ziv@2235: 
ziv@2235:     val conflictMaps = List.mapPartial (mergeEqs o map eqsOfClass o equivClasses) o dnf
ziv@2235: 
ziv@2235: end
ziv@2235: 
ziv@2235: val conflictMaps = ConflictMaps.conflictMaps
ziv@2213: 
ziv@2216: val rec sqexpToFormula =
ziv@2234:  fn Sql.SqTrue => Combo (Conj, [])
ziv@2234:   | Sql.SqFalse => Combo (Disj, [])
ziv@2216:   | Sql.SqNot e => Negate (sqexpToFormula e)
ziv@2216:   | Sql.Binop (Sql.RCmp c, e1, e2) => Atom (c, e1, e2)
ziv@2234:   | Sql.Binop (Sql.RLop l, p1, p2) => Combo (case l of Sql.And => Conj | Sql.Or => Disj,
ziv@2216:                                              [sqexpToFormula p1, sqexpToFormula p2])
ziv@2216:   (* ASK: any other sqexps that can be props? *)
ziv@2216:   | _ => raise Match
ziv@2213: 
ziv@2218: fun renameTables tablePairs =
ziv@2216:     let
ziv@2216:         fun renameString table =
ziv@2216:             case List.find (fn (_, t) => table = t) tablePairs of
ziv@2216:                 NONE => table
ziv@2216:               | SOME (realTable, _) => realTable
ziv@2216:         val renameSqexp =
ziv@2216:          fn Sql.Field (table, field) => Sql.Field (renameString table, field)
ziv@2216:           | e => e
ziv@2218:         fun renameAtom (cmp, e1, e2) = (cmp, renameSqexp e1, renameSqexp e2)
ziv@2216:     in
ziv@2218:         mapFormula renameAtom
ziv@2216:     end
ziv@2218: 
ziv@2218: val rec queryToFormula =
ziv@2234:  fn Sql.Query1 {Where = NONE, ...} => Combo (Conj, [])
ziv@2218:   | Sql.Query1 {From = tablePairs, Where = SOME e, ...} =>
ziv@2218:     renameTables tablePairs (sqexpToFormula e)
ziv@2234:   | Sql.Union (q1, q2) => Combo (Disj, [queryToFormula q1, queryToFormula q2])
ziv@2216: 
ziv@2218: fun valsToFormula (table, vals) =
ziv@2234:     Combo (Conj, map (fn (field, v) => Atom (Sql.Eq, Sql.Field (table, field), v)) vals)
ziv@2218: 
ziv@2216: val rec dmlToFormula =
ziv@2221:  fn Sql.Insert (table, vals) => valsToFormula (table, vals)
ziv@2218:   | Sql.Delete (table, wher) => renameTables [(table, "T")] (sqexpToFormula wher)
ziv@2218:   | Sql.Update (table, vals, wher) =>
ziv@2218:     let
ziv@2221:         val fWhere = sqexpToFormula wher
ziv@2221:         val fVals = valsToFormula (table, vals)
ziv@2221:         (* TODO: don't use field name hack. *)
ziv@2221:         val markField =
ziv@2221:          fn Sql.Field (t, v) => Sql.Field (t, v ^ "*")
ziv@2221:           | e => e
ziv@2221:         val mark = mapFormula (fn (cmp, e1, e2) => (cmp, markField e1, markField e2))
ziv@2218:     in
ziv@2218:         renameTables [(table, "T")]
ziv@2234:                      (Combo (Disj, [Combo (Conj, [fVals, mark fWhere]),
ziv@2234:                                    Combo (Conj, [mark fVals, fWhere])]))
ziv@2218:     end
ziv@2213: 
ziv@2213: val rec tablesQuery =
ziv@2216:  fn Sql.Query1 {From = tablePairs, ...} => SS.fromList (map #1 tablePairs)
ziv@2216:   | Sql.Union (q1, q2) => SS.union (tablesQuery q1, tablesQuery q2)
ziv@2213: 
ziv@2213: val tableDml =
ziv@2216:  fn Sql.Insert (tab, _) => tab
ziv@2216:   | Sql.Delete (tab, _) => tab
ziv@2216:   | Sql.Update (tab, _, _) => tab
ziv@2213: 
ziv@2213: 
ziv@2213: (* Program instrumentation. *)
ziv@2213: 
ziv@2234: val varName =
ziv@2234:     let
ziv@2234:         val varNumber = ref 0
ziv@2234:     in
ziv@2234:         fn s => (varNumber := !varNumber + 1; s ^ Int.toString (!varNumber))
ziv@2234:     end
ziv@2234: 
ziv@2233: val {check, store, flush, ...} = getCache ()
ziv@2233: 
ziv@2230: val dummyLoc = ErrorMsg.dummySpan
ziv@2216: 
ziv@2230: fun stringExp s = (EPrim (Prim.String (Prim.Normal, s)), dummyLoc)
ziv@2230: 
ziv@2230: val stringTyp = (TFfi ("Basis", "string"), dummyLoc)
ziv@2213: 
ziv@2213: val sequence =
ziv@2213:  fn (exp :: exps) =>
ziv@2213:     let
ziv@2230:         val loc = dummyLoc
ziv@2213:     in
ziv@2213:         List.foldl (fn (e', seq) => ESeq ((seq, loc), (e', loc))) exp exps
ziv@2213:     end
ziv@2213:   | _ => raise Match
ziv@2213: 
ziv@2215: (* Always increments negative indices because that's what we need later. *)
ziv@2215: fun incRelsBound bound inc =
ziv@2215:     MonoUtil.Exp.mapB
ziv@2215:         {typ = fn x => x,
ziv@2215:          exp = fn level =>
ziv@2215:                   (fn ERel n => ERel (if n >= level orelse n < 0 then n + inc else n)
ziv@2215:                     | x => x),
ziv@2215:          bind = fn (level, MonoUtil.Exp.RelE _) => level + 1 | (level, _) => level}
ziv@2215:         bound
ziv@2215: 
ziv@2215: val incRels = incRelsBound 0
ziv@2213: 
ziv@2223: fun cacheWrap (query, i, urlifiedRel0, resultTyp, args) =
ziv@2213:     let
ziv@2223:         val () = ffiInfo := {index = i, params = length args} :: !ffiInfo
ziv@2230:         val loc = dummyLoc
ziv@2223:         (* We ensure before this step that all arguments aren't effectful.
ziv@2227:            by turning them into local variables as needed. *)
ziv@2230:         val argsInc = map (incRels 1) args
ziv@2233:         val check = (check (i, args), dummyLoc)
ziv@2233:         val store = (store (i, argsInc, urlifiedRel0), dummyLoc)
ziv@2223:         val rel0 = (ERel 0, loc)
ziv@2213:     in
ziv@2223:         ECase (check,
ziv@2223:                [((PNone stringTyp, loc),
ziv@2234:                  (ELet (varName "q", resultTyp, query, (ESeq (store, rel0), loc)), loc)),
ziv@2234:                 ((PSome (stringTyp, (PVar (varName "hit", stringTyp), loc)), loc),
ziv@2223:                  (* Boolean is false because we're not unurlifying from a cookie. *)
ziv@2223:                  (EUnurlify (rel0, resultTyp, false), loc))],
ziv@2223:                {disc = stringTyp, result = resultTyp})
ziv@2213:     end
ziv@2213: 
ziv@2213: fun fileMapfold doExp file start =
ziv@2213:     case MonoUtil.File.mapfold {typ = Search.return2,
ziv@2213:                                 exp = fn x => (fn s => Search.Continue (doExp x s)),
ziv@2213:                                 decl = Search.return2} file start of
ziv@2213:         Search.Continue x => x
ziv@2213:       | Search.Return _ => raise Match
ziv@2213: 
ziv@2213: fun fileMap doExp file = #1 (fileMapfold (fn x => fn _ => (doExp x, ())) file ())
ziv@2213: 
ziv@2221: fun factorOutNontrivial text =
ziv@2221:     let
ziv@2230:         val loc = dummyLoc
ziv@2221:         fun strcat (e1, e2) = (EStrcat (e1, e2), loc)
ziv@2221:         val chunks = Sql.chunkify text
ziv@2221:         val (newText, newVariables) =
ziv@2221:             (* Important that this is foldr (to oppose foldl below). *)
ziv@2221:             List.foldr
ziv@2221:                 (fn (chunk, (qText, newVars)) =>
ziv@2221:                     (* Variable bound to the head of newBs will have the lowest index. *)
ziv@2221:                     case chunk of
ziv@2221:                         Sql.Exp (e as (EPrim _, _)) => (strcat (e, qText), newVars)
ziv@2221:                       | Sql.Exp e =>
ziv@2221:                         let
ziv@2221:                             val n = length newVars
ziv@2221:                         in
ziv@2221:                             (* This is the (n + 1)th new variable, so there are
ziv@2221:                                already n new variables bound, so we increment
ziv@2221:                                indices by n. *)
ziv@2221:                             (strcat ((ERel (~(n+1)), loc), qText), incRels n e :: newVars)
ziv@2221:                         end
ziv@2221:                       | Sql.String s => (strcat (stringExp s, qText), newVars))
ziv@2221:                 (stringExp "", [])
ziv@2221:                 chunks
ziv@2221:         fun wrapLets e' =
ziv@2221:             (* Important that this is foldl (to oppose foldr above). *)
ziv@2234:             List.foldl (fn (v, e') => ELet (varName "sqlArg", stringTyp, v, (e', loc)))
ziv@2221:                        e'
ziv@2221:                        newVariables
ziv@2221:         val numArgs = length newVariables
ziv@2221:     in
ziv@2221:         (newText, wrapLets, numArgs)
ziv@2221:     end
ziv@2221: 
ziv@2215: fun addChecking file =
ziv@2213:     let
ziv@2223:         fun doExp (queryInfo as (tableToIndices, indexToQueryNumArgs, index)) =
ziv@2223:          fn e' as EQuery {query = origQueryText,
ziv@2223:                           sqlcacheInfo = urlifiedRel0,
ziv@2223:                           state = resultTyp,
ziv@2223:                           initial, body, tables, exps} =>
ziv@2213:             let
ziv@2221:                 val (newQueryText, wrapLets, numArgs) = factorOutNontrivial origQueryText
ziv@2215:                 (* Increment once for each new variable just made. *)
ziv@2221:                 val queryExp = incRels numArgs
ziv@2215:                                        (EQuery {query = newQueryText,
ziv@2223:                                                 sqlcacheInfo = urlifiedRel0,
ziv@2223:                                                 state = resultTyp,
ziv@2215:                                                 initial = initial,
ziv@2215:                                                 body = body,
ziv@2215:                                                 tables = tables,
ziv@2223:                                                 exps = exps},
ziv@2230:                                         dummyLoc)
ziv@2215:                 val (EQuery {query = queryText, ...}, _) = queryExp
ziv@2235:                 (* DEBUG *)
ziv@2221:                 val () = Print.preface ("sqlcache> ", (MonoPrint.p_exp MonoEnv.empty queryText))
ziv@2230:                 val args = List.tabulate (numArgs, fn n => (ERel n, dummyLoc))
ziv@2213:                 fun bind x f = Option.mapPartial f x
ziv@2215:                 fun guard b x = if b then x else NONE
ziv@2215:                 (* DEBUG: set first boolean argument to true to turn on printing. *)
ziv@2215:                 fun safe bound = not o effectful true (effectfulMap file) false bound
ziv@2213:                 val attempt =
ziv@2213:                     (* Ziv misses Haskell's do notation.... *)
ziv@2215:                     guard (safe 0 queryText andalso safe 0 initial andalso safe 2 body) (
ziv@2216:                     bind (Sql.parse Sql.query queryText) (fn queryParsed =>
ziv@2223:                     SOME (wrapLets (cacheWrap (queryExp, index, urlifiedRel0, resultTyp, args)),
ziv@2218:                           (SS.foldr (fn (tab, qi) => SIMM.insert (qi, tab, index))
ziv@2218:                                     tableToIndices
ziv@2218:                                     (tablesQuery queryParsed),
ziv@2223:                            IM.insert (indexToQueryNumArgs, index, (queryParsed, numArgs)),
ziv@2223:                            index + 1))))
ziv@2213:             in
ziv@2213:                 case attempt of
ziv@2213:                     SOME pair => pair
ziv@2213:                   | NONE => (e', queryInfo)
ziv@2213:             end
ziv@2213:           | e' => (e', queryInfo)
ziv@2213:     in
ziv@2223:         fileMapfold (fn exp => fn state => doExp state exp) file (SIMM.empty, IM.empty, 0)
ziv@2213:     end
ziv@2213: 
ziv@2235: structure Invalidations = struct
ziv@2235: 
ziv@2235:     val loc = dummyLoc
ziv@2235: 
ziv@2235:     val optionAtomExpToExp =
ziv@2235:      fn NONE => (ENone stringTyp, loc)
ziv@2235:       | SOME e => (ESome (stringTyp,
ziv@2235:                           (case e of
ziv@2235:                                DmlRel n => ERel n
ziv@2235:                              | Prim p => EPrim p
ziv@2235:                              (* TODO: make new type containing only these two. *)
ziv@2235:                              | _ => raise Match,
ziv@2235:                            loc)),
ziv@2235:                    loc)
ziv@2235: 
ziv@2235:     fun eqsToInvalidation numArgs eqs =
ziv@2235:         let
ziv@2235:             fun inv n = if n < 0 then [] else IM.find (eqs, n) :: inv (n - 1)
ziv@2235:         in
ziv@2235:             inv (numArgs - 1)
ziv@2235:         end
ziv@2235: 
ziv@2235:     (* Tests if [ys] makes [xs] a redundant cache invalidation. [NONE] here
ziv@2235:        represents unknown, which means a wider invalidation. *)
ziv@2235:     val rec madeRedundantBy : atomExp option list * atomExp option list -> bool =
ziv@2235:      fn ([], []) => true
ziv@2235:       | (NONE :: xs, _ :: ys) => madeRedundantBy (xs, ys)
ziv@2235:       | (SOME x :: xs, SOME y :: ys) => (case AtomExpKey.compare (x, y) of
ziv@2235:                                              EQUAL => madeRedundantBy (xs, ys)
ziv@2235:                                            | _ => false)
ziv@2235:       | _ => false
ziv@2235: 
ziv@2235:     fun removeRedundant' (xss, yss) =
ziv@2235:         case xss of
ziv@2235:             [] => yss
ziv@2235:           | xs :: xss' =>
ziv@2235:             removeRedundant' (xss',
ziv@2235:                               if List.exists (fn ys => madeRedundantBy (xs, ys)) (xss' @ yss)
ziv@2235:                               then yss
ziv@2235:                               else xs :: yss)
ziv@2235: 
ziv@2235:     fun removeRedundant xss = removeRedundant' (xss, [])
ziv@2235: 
ziv@2235:     fun eqss (query, dml) = conflictMaps (queryToFormula query, dmlToFormula dml)
ziv@2235: 
ziv@2235:     fun invalidations ((query, numArgs), dml) =
ziv@2235:         (map (map optionAtomExpToExp)
ziv@2235:          o removeRedundant
ziv@2235:          o map (eqsToInvalidation numArgs)
ziv@2235:          o eqss)
ziv@2235:             (query, dml)
ziv@2235: 
ziv@2235: end
ziv@2235: 
ziv@2235: val invalidations = Invalidations.invalidations
ziv@2235: 
ziv@2235: (* DEBUG *)
ziv@2235: val gunk : ((Sql.query * int) * Sql.dml) list ref = ref []
ziv@2216: 
ziv@2223: fun addFlushing (file, (tableToIndices, indexToQueryNumArgs, _)) =
ziv@2213:     let
ziv@2221:         val flushes = List.concat o
ziv@2233:                       map (fn (i, argss) => map (fn args => flush (i, args)) argss)
ziv@2213:         val doExp =
ziv@2221:          fn EDml (origDmlText, failureMode) =>
ziv@2213:             let
ziv@2221:                 val (newDmlText, wrapLets, numArgs) = factorOutNontrivial origDmlText
ziv@2221:                 val dmlText = incRels numArgs newDmlText
ziv@2221:                 val dmlExp = EDml (dmlText, failureMode)
ziv@2235:                 (* DEBUG *)
ziv@2221:                 val () = Print.preface ("sqlcache> ", (MonoPrint.p_exp MonoEnv.empty dmlText))
ziv@2221:                 val invs =
ziv@2216:                     case Sql.parse Sql.dml dmlText of
ziv@2218:                         SOME dmlParsed =>
ziv@2221:                         map (fn i => (case IM.find (indexToQueryNumArgs, i) of
ziv@2221:                                           SOME queryNumArgs =>
ziv@2235:                                           (* DEBUG *)
ziv@2235:                                           (gunk := (queryNumArgs, dmlParsed) :: !gunk;
ziv@2235:                                            (i, invalidations (queryNumArgs, dmlParsed)))
ziv@2221:                                         (* TODO: fail more gracefully. *)
ziv@2221:                                         | NONE => raise Match))
ziv@2221:                             (SIMM.findList (tableToIndices, tableDml dmlParsed))
ziv@2221:                       (* TODO: fail more gracefully. *)
ziv@2221:                       | NONE => raise Match
ziv@2213:             in
ziv@2221:                 wrapLets (sequence (flushes invs @ [dmlExp]))
ziv@2213:             end
ziv@2213:           | e' => e'
ziv@2213:     in
ziv@2235:         (* DEBUG *)
ziv@2235:         gunk := [];
ziv@2213:         fileMap doExp file
ziv@2213:     end
ziv@2213: 
ziv@2221: val inlineSql =
ziv@2221:     let
ziv@2221:         val doExp =
ziv@2221:          (* TODO: EQuery, too? *)
ziv@2221:          (* ASK: should this live in [MonoOpt]? *)
ziv@2221:          fn EDml ((ECase (disc, cases, {disc = dTyp, ...}), loc), failureMode) =>
ziv@2221:             let
ziv@2221:                 val newCases = map (fn (p, e) => (p, (EDml (e, failureMode), loc))) cases
ziv@2221:             in
ziv@2221:                 ECase (disc, newCases, {disc = dTyp, result = (TRecord [], loc)})
ziv@2221:             end
ziv@2221:           | e => e
ziv@2221:     in
ziv@2221:         fileMap doExp
ziv@2221:     end
ziv@2221: 
ziv@2213: fun go file =
ziv@2213:     let
ziv@2235:         (* TODO: do something nicer than [Sql] being in one of two modes. *)
ziv@2227:         val () = (resetFfiInfo (); Sql.sqlcacheMode := true)
ziv@2221:         val file' = addFlushing (addChecking (inlineSql file))
ziv@2215:         val () = Sql.sqlcacheMode := false
ziv@2213:     in
ziv@2221:         file'
ziv@2213:     end
ziv@2213: 
ziv@2209: end