adamc@134: (* Copyright (c) 2008, Adam Chlipala
adamc@134:  * All rights reserved.
adamc@134:  *
adamc@134:  * Redistribution and use in source and binary forms, with or without
adamc@134:  * modification, are permitted provided that the following conditions are met:
adamc@134:  *
adamc@134:  * - Redistributions of source code must retain the above copyright notice,
adamc@134:  *   this list of conditions and the following disclaimer.
adamc@134:  * - Redistributions in binary form must reproduce the above copyright notice,
adamc@134:  *   this list of conditions and the following disclaimer in the documentation
adamc@134:  *   and/or other materials provided with the distribution.
adamc@134:  * - The names of contributors may not be used to endorse or promote products
adamc@134:  *   derived from this software without specific prior written permission.
adamc@134:  *
adamc@134:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
adamc@134:  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
adamc@134:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
adamc@134:  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
adamc@134:  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
adamc@134:  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
adamc@134:  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
adamc@134:  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
adamc@134:  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
adamc@134:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
adamc@134:  * POSSIBILITY OF SUCH DAMAGE.
adamc@134:  *)
adamc@134: 
adamc@134: (* Remove unused definitions from a file *)
adamc@134: 
adamc@134: structure MonoShake :> MONO_SHAKE = struct
adamc@134: 
adamc@134: open Mono
adamc@134: 
adamc@134: structure U = MonoUtil
adamc@134: 
adamc@134: structure IS = IntBinarySet
adamc@134: structure IM = IntBinaryMap
adamc@134: 
adamc@134: type free = {
adamc@134:      con : IS.set,
adamc@134:      exp : IS.set
adamc@134: }
adamc@134: 
adamc@134: fun shake file =
adamc@134:     let
adamc@1073:         val usedVars = U.Exp.fold {typ = fn (c, st as (cs, es)) =>
adamc@1073:                                             case c of
adamc@1073:                                                 TDatatype (n, _) => (IS.add (cs, n), es)
adamc@1073:                                               | _ => st,
adamc@1073:                                    exp = fn (e, st as (cs, es)) =>
adamc@1073:                                             case e of
adamc@1073:                                                 ENamed n => (cs, IS.add (es, n))
adamc@1073:                                               | _ => st}
adamc@1073: 
adamc@1073:         val (page_cs, page_es) =
adamc@1073:             List.foldl
adamc@1104:                 (fn ((DExport (_, _, n, _, _, _), _), (page_cs, page_es)) => (page_cs, IS.add (page_es, n))
adamc@1073:                   | ((DDatabase {expunge = n1, initialize = n2, ...}, _), (page_cs, page_es)) =>
adamc@1073:                     (page_cs, IS.addList (page_es, [n1, n2]))
adamc@1075:                   | ((DTask (e1, e2), _), st) => usedVars (usedVars st e2) e1
adamc@1199:                   | ((DPolicy pol, _), st) =>
adamc@1199:                     let
adamc@1199:                         val e1 = case pol of
adamc@1199:                                      PolQuery e1 => e1
adamc@1199:                     in
adamc@1199:                         usedVars st e1
adamc@1199:                     end
adamc@1073:                   | (_, st) => st) (IS.empty, IS.empty) file
adamc@134: 
adamc@808:         val (cdef, edef) = foldl (fn ((DDatatype dts, _), (cdef, edef)) =>
adamc@808:                                      (foldl (fn ((_, n, xncs), cdef) => IM.insert (cdef, n, xncs)) cdef dts, edef)
adamc@178:                                    | ((DVal (_, n, t, e, _), _), (cdef, edef)) =>
adamc@178:                                      (cdef, IM.insert (edef, n, (t, e)))
adamc@134:                                    | ((DValRec vis, _), (cdef, edef)) =>
adamc@134:                                      (cdef, foldl (fn ((_, n, t, e, _), edef) => IM.insert (edef, n, (t, e))) edef vis)
adamc@271:                                    | ((DExport _, _), acc) => acc
adamc@273:                                    | ((DTable _, _), acc) => acc
adamc@338:                                    | ((DSequence _, _), acc) => acc
adamc@754:                                    | ((DView _, _), acc) => acc
adamc@569:                                    | ((DDatabase _, _), acc) => acc
adamc@718:                                    | ((DJavaScript _, _), acc) => acc
adamc@725:                                    | ((DCookie _, _), acc) => acc
adamc@1073:                                    | ((DStyle _, _), acc) => acc
adamc@1199:                                    | ((DTask _, _), acc) => acc
adamc@1199:                                    | ((DPolicy _, _), acc) => acc)
adamc@134:                                  (IM.empty, IM.empty) file
adamc@134: 
adamc@164:         fun typ (c, s) =
adamc@164:             case c of
adamc@196:                 TDatatype (n, _) =>
adamc@164:                 if IS.member (#con s, n) then
adamc@164:                     s
adamc@164:                 else
adamc@178:                     let
adamc@178:                         val s' = {exp = #exp s,
adamc@178:                                   con = IS.add (#con s, n)}
adamc@178:                     in
adamc@178:                         case IM.find (cdef, n) of
adamc@178:                             NONE => s'
adamc@178:                           | SOME xncs => foldl (fn ((_, _, to), s) =>
adamc@178:                                                    case to of
adamc@178:                                                        NONE => s
adamc@178:                                                      | SOME t => shakeTyp s t)
adamc@178:                                          s' xncs
adamc@178:                     end
adamc@164:               | _ => s
adamc@134: 
adamc@178:         and shakeTyp s = U.Typ.fold typ s
adamc@178: 
adamc@134:         fun exp (e, s) =
adamc@134:             case e of
adamc@134:                 ENamed n =>
adamc@134:                 if IS.member (#exp s, n) then
adamc@134:                     s
adamc@134:                 else
adamc@134:                     let
adamc@134:                         val s' = {exp = IS.add (#exp s, n),
adamc@134:                                   con = #con s}
adamc@134:                     in
adamc@134:                         case IM.find (edef, n) of
adamc@134:                             NONE => s'
adamc@134:                           | SOME (t, e) => shakeExp s' e
adamc@134:                     end
adamc@134:               | _ => s
adamc@134: 
adamc@134:         and shakeExp s = U.Exp.fold {typ = typ, exp = exp} s
adamc@134: 
adamc@1073:         val s = {con = page_cs, exp = page_es}
adamc@134: 
adamc@1073:         val s = IS.foldl (fn (n, s) =>
adamc@1073:                              case IM.find (cdef, n) of
adamc@1073:                                  NONE => raise Fail "MonoShake: Couldn't find 'datatype'"
adamc@1073:                                | SOME xncs => foldl (fn ((_, _, SOME c), s) => shakeTyp s c
adamc@1073:                                                       | _ => s) s xncs) s page_cs
adamc@1073: 
adamc@1073:         val s = IS.foldl (fn (n, s) =>
adamc@1073:                              case IM.find (edef, n) of
adamc@1073:                                  NONE => raise Fail "MonoShake: Couldn't find 'val'"
adamc@1073:                                | SOME (t, e) => shakeExp s e) s page_es
adamc@134:     in
adamc@808:         List.filter (fn (DDatatype dts, _) => List.exists (fn (_, n, _) => IS.member (#con s, n)) dts
adamc@164:                       | (DVal (_, n, _, _, _), _) => IS.member (#exp s, n)
adamc@134:                       | (DValRec vis, _) => List.exists (fn (_, n, _, _, _) => IS.member (#exp s, n)) vis
adamc@271:                       | (DExport _, _) => true
adamc@273:                       | (DTable _, _) => true
adamc@338:                       | (DSequence _, _) => true
adamc@754:                       | (DView _, _) => true
adamc@569:                       | (DDatabase _, _) => true
adamc@718:                       | (DJavaScript _, _) => true
adamc@725:                       | (DCookie _, _) => true
adamc@1073:                       | (DStyle _, _) => true
adamc@1199:                       | (DTask _, _) => true
adamc@1199:                       | (DPolicy _, _) => true) file
adamc@134:     end
adamc@134: 
adamc@134: end