Especialize

1 files changed, 176 insertions, 0 deletions

diff --git a/src/especialize.sml b/src/especialize.sml
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+(* Copyright (c) 2008, Adam Chlipala
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright notice,
+ *   this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright notice,
+ *   this list of conditions and the following disclaimer in the documentation
+ *   and/or other materials provided with the distribution.
+ * - The names of contributors may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *)
+
+structure ESpecialize :> ESPECIALIZE = struct
+
+open Core
+
+structure E = CoreEnv
+structure U = CoreUtil
+
+structure ILK = struct
+type ord_key = int list
+val compare = Order.joinL Int.compare
+end
+
+structure ILM = BinaryMapFn(ILK)
+structure IM = IntBinaryMap
+
+type func = {
+     name : string,
+     args : int ILM.map,
+     body : exp,
+     typ : con,
+     tag : string
+}
+
+type state = {
+     maxName : int,
+     funcs : func IM.map,
+     decls : (string * int * con * exp * string) list
+}
+
+fun kind (k, st) = (k, st)
+fun con (c, st) = (c, st)
+
+fun exp (e, st : state) =
+    let
+        fun getApp e =
+            case e of
+                ENamed f => SOME (f, [], [])
+              | EApp (e1, (ENamed x, _)) =>
+                (case getApp (#1 e1) of
+                     NONE => NONE
+                   | SOME (f, xs, xs') => SOME (f, xs @ [x], xs'))
+              | EApp (e1, e2) =>
+                (case getApp (#1 e1) of
+                     NONE => NONE
+                   | SOME (f, xs, xs') => SOME (f, xs, xs' @ [e2]))
+              | _ => NONE
+    in
+        case getApp e of
+            NONE => (e, st)
+          | SOME (_, [], _) => (e, st)
+          | SOME (f, xs, xs') =>
+            case IM.find (#funcs st, f) of
+                NONE => (e, st)
+              | SOME {name, args, body, typ, tag} =>
+                case ILM.find (args, xs) of
+                    SOME f' => (#1 (foldl (fn (e, arg) => (EApp (e, arg), ErrorMsg.dummySpan))
+                                          (ENamed f', ErrorMsg.dummySpan) xs'),
+                                st)
+                  | NONE =>
+                    let
+                        fun subBody (body, typ, xs) =
+                            case (#1 body, #1 typ, xs) of
+                                (_, _, []) => SOME (body, typ)
+                              | (EAbs (_, _, _, body'), TFun (_, typ'), x :: xs) =>
+                                subBody (E.subExpInExp (0, (ENamed x, ErrorMsg.dummySpan)) body',
+                                         typ',
+                                         xs)
+                              | _ => NONE
+                    in
+                        case subBody (body, typ, xs) of
+                            NONE => (e, st)
+                          | SOME (body', typ') =>
+                            let
+                                val f' = #maxName st
+                                val funcs = IM.insert (#funcs st, f, {name = name,
+                                                                      args = ILM.insert (args, xs, f'),
+                                                                      body = body,
+                                                                      typ = typ,
+                                                                      tag = tag})
+                                val st = {
+                                    maxName = f' + 1,
+                                    funcs = funcs,
+                                    decls = #decls st
+                                }
+
+                                val (body', st) = specExp st body'
+                                val e' = foldl (fn (e, arg) => (EApp (e, arg), ErrorMsg.dummySpan))
+                                               (ENamed f', ErrorMsg.dummySpan) xs'
+                            in
+                                (#1 e',
+                                 {maxName = #maxName st,
+                                  funcs = #funcs st,
+                                  decls = (name, f', typ', body', tag ^ "_espec") :: #decls st})
+                            end
+                    end
+    end
+
+and specExp st = U.Exp.foldMap {kind = kind, con = con, exp = exp} st
+
+fun decl (d, st) = (d, st)
+
+val specDecl = U.Decl.foldMap {kind = kind, con = con, exp = exp, decl = decl}
+
+fun specialize file =
+    let
+        fun doDecl (d, st) =
+            let
+                val (d', st) = specDecl st d
+
+                val funcs = #funcs st
+                val funcs =
+                    case #1 d of
+                        DVal (x, n, c, e as (EAbs _, _), tag) =>
+                        IM.insert (funcs, n, {name = x,
+                                              args = ILM.empty,
+                                              body = e,
+                                              typ = c,
+                                              tag = tag})
+                      | DValRec vis =>
+                        foldl (fn ((x, n, c, e, tag), funcs) =>
+                                  IM.insert (funcs, n, {name = x,
+                                                        args = ILM.empty,
+                                                        body = e,
+                                                        typ = c,
+                                                        tag = tag}))
+                              funcs vis
+                      | _ => funcs
+
+                val ds =
+                    case #decls st of
+                        [] => [d']
+                      | vis => [(DValRec vis, ErrorMsg.dummySpan), d']
+            in
+                (ds, {maxName = #maxName st,
+                      funcs = funcs,
+                      decls = []})
+            end
+
+        val (ds, _) = ListUtil.foldlMapConcat doDecl
+                      {maxName = U.File.maxName file + 1,
+                       funcs = IM.empty,
+                       decls = []}
+                      file
+    in
+        ds
+    end
+
+
+end