annotate src/shake.sml @ 132:25b28625d4df

Proper topological sorting in untangle
author Adam Chlipala <adamc@hcoop.net>
date Thu, 17 Jul 2008 12:40:21 -0400
parents fd98dd10dce7
children f0d3402184d1
rev   line source
adamc@23 1 (* Copyright (c) 2008, Adam Chlipala
adamc@23 2 * All rights reserved.
adamc@23 3 *
adamc@23 4 * Redistribution and use in source and binary forms, with or without
adamc@23 5 * modification, are permitted provided that the following conditions are met:
adamc@23 6 *
adamc@23 7 * - Redistributions of source code must retain the above copyright notice,
adamc@23 8 * this list of conditions and the following disclaimer.
adamc@23 9 * - Redistributions in binary form must reproduce the above copyright notice,
adamc@23 10 * this list of conditions and the following disclaimer in the documentation
adamc@23 11 * and/or other materials provided with the distribution.
adamc@23 12 * - The names of contributors may not be used to endorse or promote products
adamc@23 13 * derived from this software without specific prior written permission.
adamc@23 14 *
adamc@23 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
adamc@23 16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
adamc@23 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
adamc@23 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
adamc@23 19 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
adamc@23 20 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
adamc@23 21 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
adamc@23 22 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
adamc@23 23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
adamc@23 24 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
adamc@23 25 * POSSIBILITY OF SUCH DAMAGE.
adamc@23 26 *)
adamc@23 27
adamc@23 28 (* Remove unused definitions from a file *)
adamc@23 29
adamc@23 30 structure Shake :> SHAKE = struct
adamc@23 31
adamc@23 32 open Core
adamc@23 33
adamc@23 34 structure U = CoreUtil
adamc@23 35
adamc@23 36 structure IS = IntBinarySet
adamc@23 37 structure IM = IntBinaryMap
adamc@23 38
adamc@23 39 type free = {
adamc@23 40 con : IS.set,
adamc@23 41 exp : IS.set
adamc@23 42 }
adamc@23 43
adamc@23 44 fun shake file =
adamc@100 45 let
adamc@109 46 val page_es = List.foldl
adamc@109 47 (fn ((DExport n, _), page_es) => n :: page_es
adamc@109 48 | (_, page_es) => page_es) [] file
adamc@23 49
adamc@100 50 val (cdef, edef) = foldl (fn ((DCon (_, n, _, c), _), (cdef, edef)) => (IM.insert (cdef, n, c), edef)
adamc@109 51 | ((DVal (_, n, t, e, _), _), (cdef, edef)) => (cdef, IM.insert (edef, n, (t, e)))
adamc@125 52 | ((DValRec vis, _), (cdef, edef)) =>
adamc@125 53 (cdef, foldl (fn ((_, n, t, e, _), edef) => IM.insert (edef, n, (t, e))) edef vis)
adamc@109 54 | ((DExport _, _), acc) => acc)
adamc@100 55 (IM.empty, IM.empty) file
adamc@23 56
adamc@100 57 fun kind (_, s) = s
adamc@23 58
adamc@100 59 fun con (c, s) =
adamc@100 60 case c of
adamc@100 61 CNamed n =>
adamc@100 62 if IS.member (#con s, n) then
adamc@100 63 s
adamc@100 64 else
adamc@100 65 let
adamc@100 66 val s' = {con = IS.add (#con s, n),
adamc@100 67 exp = #exp s}
adamc@100 68 in
adamc@100 69 case IM.find (cdef, n) of
adamc@100 70 NONE => s'
adamc@100 71 | SOME c => shakeCon s' c
adamc@100 72 end
adamc@100 73 | _ => s
adamc@23 74
adamc@100 75 and shakeCon s = U.Con.fold {kind = kind, con = con} s
adamc@23 76
adamc@100 77 fun exp (e, s) =
adamc@100 78 case e of
adamc@100 79 ENamed n =>
adamc@100 80 if IS.member (#exp s, n) then
adamc@100 81 s
adamc@100 82 else
adamc@100 83 let
adamc@100 84 val s' = {exp = IS.add (#exp s, n),
adamc@100 85 con = #con s}
adamc@100 86 in
adamc@100 87 case IM.find (edef, n) of
adamc@100 88 NONE => s'
adamc@100 89 | SOME (t, e) => shakeExp (shakeCon s' t) e
adamc@100 90 end
adamc@100 91 | _ => s
adamc@23 92
adamc@100 93 and shakeExp s = U.Exp.fold {kind = kind, con = con, exp = exp} s
adamc@100 94
adamc@109 95 val s = {con = IS.empty, exp = IS.addList (IS.empty, page_es)}
adamc@109 96
adamc@109 97 val s = foldl (fn (n, s) =>
adamc@109 98 case IM.find (edef, n) of
adamc@109 99 NONE => raise Fail "Shake: Couldn't find 'val'"
adamc@109 100 | SOME (t, e) => shakeExp (shakeCon s t) e) s page_es
adamc@100 101 in
adamc@100 102 List.filter (fn (DCon (_, n, _, _), _) => IS.member (#con s, n)
adamc@109 103 | (DVal (_, n, _, _, _), _) => IS.member (#exp s, n)
adamc@125 104 | (DValRec vis, _) => List.exists (fn (_, n, _, _, _) => IS.member (#exp s, n)) vis
adamc@109 105 | (DExport _, _) => true) file
adamc@100 106 end
adamc@23 107
adamc@23 108 end