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annotate src/mono_reduce.sml @ 1043:d73cf02427df

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New release
author Adam Chlipala <adamc@hcoop.net>
date Tue, 24 Nov 2009 09:48:28 -0500
parents 7a4a55e05081
children 217eb87dde31
rev   line source
adamc@133 1 (* Copyright (c) 2008, Adam Chlipala
adamc@133 2 * All rights reserved.
adamc@133 3 *
adamc@133 4 * Redistribution and use in source and binary forms, with or without
adamc@133 5 * modification, are permitted provided that the following conditions are met:
adamc@133 6 *
adamc@133 7 * - Redistributions of source code must retain the above copyright notice,
adamc@133 8 * this list of conditions and the following disclaimer.
adamc@133 9 * - Redistributions in binary form must reproduce the above copyright notice,
adamc@133 10 * this list of conditions and the following disclaimer in the documentation
adamc@133 11 * and/or other materials provided with the distribution.
adamc@133 12 * - The names of contributors may not be used to endorse or promote products
adamc@133 13 * derived from this software without specific prior written permission.
adamc@133 14 *
adamc@133 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
adamc@133 16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
adamc@133 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
adamc@133 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
adamc@133 19 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
adamc@133 20 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
adamc@133 21 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
adamc@133 22 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
adamc@133 23 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
adamc@133 24 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
adamc@133 25 * POSSIBILITY OF SUCH DAMAGE.
adamc@133 26 *)
adamc@133 27
adamc@133 28 (* Simplify a Mono program algebraically *)
adamc@133 29
adamc@133 30 structure MonoReduce :> MONO_REDUCE = struct
adamc@133 31
adamc@133 32 open Mono
adamc@133 33
adamc@133 34 structure E = MonoEnv
adamc@133 35 structure U = MonoUtil
adamc@133 36
adamc@470 37 structure IM = IntBinaryMap
adamc@916 38 structure IS = IntBinarySet
adamc@470 39
adamc@133 40
adamc@948 41 fun simpleTypeImpure tsyms =
adamc@919 42 U.Typ.exists (fn TFun _ => true
adamc@948 43 | TDatatype (n, _) => IS.member (tsyms, n)
adamc@919 44 | _ => false)
adamc@919 45
adamc@948 46 fun simpleImpure (tsyms, syms) =
adamc@919 47 U.Exp.existsB {typ = fn _ => false,
adamc@919 48 exp = fn (env, e) =>
adamc@919 49 case e of
adamc@919 50 EWrite _ => true
adamc@919 51 | EQuery _ => true
adamc@919 52 | EDml _ => true
adamc@919 53 | ENextval _ => true
adamc@919 54 | EFfiApp (m, x, _) => Settings.isEffectful (m, x)
adamc@919 55 | EServerCall _ => true
adamc@919 56 | ERecv _ => true
adamc@919 57 | ESleep _ => true
adamc@919 58 | ENamed n => IS.member (syms, n)
adamc@919 59 | ERel n =>
adamc@919 60 let
adamc@919 61 val (_, t, _) = E.lookupERel env n
adamc@919 62 in
adamc@948 63 simpleTypeImpure tsyms t
adamc@919 64 end
adamc@919 65 | _ => false,
adamc@919 66 bind = fn (env, b) =>
adamc@919 67 case b of
adamc@919 68 U.Exp.RelE (x, t) => E.pushERel env x t NONE
adamc@919 69 | _ => env}
adamc@916 70
adamc@252 71 fun impure (e, _) =
adamc@252 72 case e of
adamc@252 73 EWrite _ => true
adamc@252 74 | EQuery _ => true
adamc@307 75 | EDml _ => true
adamc@338 76 | ENextval _ => true
adamc@463 77 | EUnurlify _ => true
adamc@252 78 | EAbs _ => false
adamc@252 79
adamc@252 80 | EPrim _ => false
adamc@252 81 | ERel _ => false
adamc@252 82 | ENamed _ => false
adamc@252 83 | ECon (_, _, eo) => (case eo of NONE => false | SOME e => impure e)
adamc@297 84 | ENone _ => false
adamc@290 85 | ESome (_, e) => impure e
adamc@252 86 | EFfi _ => false
adamc@765 87 | EFfiApp (m, x, _) => Settings.isEffectful (m, x)
adamc@252 88 | EApp ((EFfi _, _), _) => false
adamc@252 89 | EApp _ => true
adamc@252 90
adamc@387 91 | EUnop (_, e) => impure e
adamc@387 92 | EBinop (_, e1, e2) => impure e1 orelse impure e2
adamc@387 93
adamc@252 94 | ERecord xes => List.exists (fn (_, e, _) => impure e) xes
adamc@252 95 | EField (e, _) => impure e
adamc@252 96
adamc@252 97 | ECase (e, pes, _) => impure e orelse List.exists (fn (_, e) => impure e) pes
adamc@252 98
adamc@283 99 | EError (e, _) => impure e
adamc@741 100 | EReturnBlob {blob = e1, mimeType = e2, ...} => impure e1 orelse impure e2
adamc@283 101
adamc@252 102 | EStrcat (e1, e2) => impure e1 orelse impure e2
adamc@252 103
adamc@252 104 | ESeq (e1, e2) => impure e1 orelse impure e2
adamc@252 105 | ELet (_, _, e1, e2) => impure e1 orelse impure e2
adamc@252 106
adamc@252 107 | EClosure (_, es) => List.exists impure es
adamc@815 108 | EJavaScript (_, e) => impure e
adamc@568 109 | ESignalReturn e => impure e
adamc@572 110 | ESignalBind (e1, e2) => impure e1 orelse impure e2
adamc@574 111 | ESignalSource e => impure e
adamc@608 112 | EServerCall _ => true
adamc@670 113 | ERecv _ => true
adamc@695 114 | ESleep _ => true
adamc@1021 115 | ESpawn _ => true
adamc@252 116
adamc@252 117 val liftExpInExp = Monoize.liftExpInExp
adamc@252 118
adamc@829 119 fun multiLift n e =
adamc@829 120 case n of
adamc@829 121 0 => e
adamc@829 122 | _ => multiLift (n - 1) (liftExpInExp 0 e)
adamc@829 123
adamc@252 124 val subExpInExp' =
adamc@133 125 U.Exp.mapB {typ = fn t => t,
adamc@133 126 exp = fn (xn, rep) => fn e =>
adamc@133 127 case e of
adamc@133 128 ERel xn' =>
adamc@133 129 (case Int.compare (xn', xn) of
adamc@133 130 EQUAL => #1 rep
adamc@133 131 | GREATER=> ERel (xn' - 1)
adamc@133 132 | LESS => e)
adamc@133 133 | _ => e,
adamc@133 134 bind = fn ((xn, rep), U.Exp.RelE _) => (xn+1, liftExpInExp 0 rep)
adamc@133 135 | (ctx, _) => ctx}
adamc@133 136
adamc@252 137 fun subExpInExp (n, e1) e2 =
adamc@252 138 let
adamc@252 139 val r = subExpInExp' (n, e1) e2
adamc@252 140 in
adamc@252 141 (*Print.prefaces "subExpInExp" [("e1", MonoPrint.p_exp MonoEnv.empty e1),
adamc@252 142 ("e2", MonoPrint.p_exp MonoEnv.empty e2),
adamc@252 143 ("r", MonoPrint.p_exp MonoEnv.empty r)];*)
adamc@252 144 r
adamc@252 145 end
adamc@133 146
adamc@133 147 fun typ c = c
adamc@133 148
adamc@316 149 val swapExpVars =
adamc@316 150 U.Exp.mapB {typ = fn t => t,
adamc@316 151 exp = fn lower => fn e =>
adamc@316 152 case e of
adamc@316 153 ERel xn =>
adamc@316 154 if xn = lower then
adamc@316 155 ERel (lower + 1)
adamc@316 156 else if xn = lower + 1 then
adamc@316 157 ERel lower
adamc@316 158 else
adamc@316 159 e
adamc@316 160 | _ => e,
adamc@316 161 bind = fn (lower, U.Exp.RelE _) => lower+1
adamc@316 162 | (lower, _) => lower}
adamc@316 163
adamc@341 164 val swapExpVarsPat =
adamc@341 165 U.Exp.mapB {typ = fn t => t,
adamc@341 166 exp = fn (lower, len) => fn e =>
adamc@341 167 case e of
adamc@341 168 ERel xn =>
adamc@341 169 if xn = lower then
adamc@827 170 ERel (lower + len)
adamc@341 171 else if xn >= lower + 1 andalso xn < lower + 1 + len then
adamc@341 172 ERel (xn - 1)
adamc@341 173 else
adamc@341 174 e
adamc@341 175 | _ => e,
adamc@341 176 bind = fn ((lower, len), U.Exp.RelE _) => (lower+1, len)
adamc@341 177 | (st, _) => st}
adamc@341 178
adamc@814 179 datatype result = Yes of exp list | No | Maybe
adamc@258 180
adamc@183 181 fun match (env, p : pat, e : exp) =
adamc@183 182 case (#1 p, #1 e) of
adamc@258 183 (PWild, _) => Yes env
adamc@814 184 | (PVar (x, t), _) => Yes (e :: env)
adamc@183 185
adamc@280 186 | (PPrim (Prim.String s), EStrcat ((EPrim (Prim.String s'), _), _)) =>
adamc@280 187 if String.isPrefix s' s then
adamc@280 188 Maybe
adamc@280 189 else
adamc@280 190 No
adamc@280 191
adamc@183 192 | (PPrim p, EPrim p') =>
adamc@183 193 if Prim.equal (p, p') then
adamc@258 194 Yes env
adamc@183 195 else
adamc@258 196 No
adamc@183 197
adamc@188 198 | (PCon (_, PConVar n1, NONE), ECon (_, PConVar n2, NONE)) =>
adamc@183 199 if n1 = n2 then
adamc@258 200 Yes env
adamc@183 201 else
adamc@258 202 No
adamc@183 203
adamc@188 204 | (PCon (_, PConVar n1, SOME p), ECon (_, PConVar n2, SOME e)) =>
adamc@183 205 if n1 = n2 then
adamc@183 206 match (env, p, e)
adamc@183 207 else
adamc@258 208 No
adamc@183 209
adamc@188 210 | (PCon (_, PConFfi {mod = m1, con = con1, ...}, NONE), ECon (_, PConFfi {mod = m2, con = con2, ...}, NONE)) =>
adamc@185 211 if m1 = m2 andalso con1 = con2 then
adamc@258 212 Yes env
adamc@185 213 else
adamc@258 214 No
adamc@185 215
adamc@188 216 | (PCon (_, PConFfi {mod = m1, con = con1, ...}, SOME ep), ECon (_, PConFfi {mod = m2, con = con2, ...}, SOME e)) =>
adamc@185 217 if m1 = m2 andalso con1 = con2 then
adamc@185 218 match (env, p, e)
adamc@185 219 else
adamc@258 220 No
adamc@185 221
adamc@183 222 | (PRecord xps, ERecord xes) =>
adamc@183 223 let
adamc@183 224 fun consider (xps, env) =
adamc@183 225 case xps of
adamc@258 226 [] => Yes env
adamc@183 227 | (x, p, _) :: rest =>
adamc@183 228 case List.find (fn (x', _, _) => x' = x) xes of
adamc@258 229 NONE => No
adamc@183 230 | SOME (_, e, _) =>
adamc@183 231 case match (env, p, e) of
adamc@258 232 No => No
adamc@258 233 | Maybe => Maybe
adamc@258 234 | Yes env => consider (rest, env)
adamc@183 235 in
adamc@183 236 consider (xps, env)
adamc@183 237 end
adamc@183 238
adamc@726 239 | (PNone _, ENone _) => Yes env
adamc@921 240 | (PNone _, ESome _) => No
adamc@726 241 | (PSome (_, p), ESome (_, e)) => match (env, p, e)
adamc@921 242 | (PSome _, ENone _) => No
adamc@726 243
adamc@258 244 | _ => Maybe
adamc@183 245
adamc@318 246 datatype event =
adamc@318 247 WritePage
adamc@318 248 | ReadDb
adamc@318 249 | WriteDb
adamc@481 250 | UseRel
adamc@318 251 | Unsure
adamc@318 252
adamc@318 253 fun p_event e =
adamc@318 254 let
adamc@318 255 open Print.PD
adamc@318 256 in
adamc@318 257 case e of
adamc@318 258 WritePage => string "WritePage"
adamc@318 259 | ReadDb => string "ReadDb"
adamc@318 260 | WriteDb => string "WriteDb"
adamc@481 261 | UseRel => string "UseRel"
adamc@318 262 | Unsure => string "Unsure"
adamc@318 263 end
adamc@318 264
adamc@470 265 val p_events = Print.p_list p_event
adamc@470 266
adamc@318 267 fun patBinds (p, _) =
adamc@318 268 case p of
adamc@318 269 PWild => 0
adamc@318 270 | PVar _ => 1
adamc@318 271 | PPrim _ => 0
adamc@318 272 | PCon (_, _, NONE) => 0
adamc@318 273 | PCon (_, _, SOME p) => patBinds p
adamc@318 274 | PRecord xpts => foldl (fn ((_, p, _), n) => n + patBinds p) 0 xpts
adamc@318 275 | PNone _ => 0
adamc@318 276 | PSome (_, p) => patBinds p
adamc@318 277
adamc@932 278 val countFree = U.Exp.foldB {typ = fn (_, n) => n,
adamc@932 279 exp = fn (x, e, n) =>
adamc@932 280 case e of
adamc@932 281 ERel x' => if x = x' then n + 1 else n
adamc@932 282 | _ => n,
adamc@932 283 bind = fn (n, b) =>
adamc@932 284 case b of
adamc@932 285 U.Exp.RelE _ => n + 1
adamc@975 286 | _ => n}
adamc@975 287
adamc@975 288 val freeInAbs = U.Exp.existsB {typ = fn _ => false,
adamc@975 289 exp = fn (n, e) =>
adamc@975 290 case e of
adamc@975 291 EAbs (_, _, _, b) => countFree n 0 b > 0
adamc@975 292 | EJavaScript (_, b) => countFree n 0 b > 0
adamc@975 293 | _ => false,
adamc@975 294 bind = fn (n, b) =>
adamc@975 295 case b of
adamc@975 296 U.Exp.RelE _ => n + 1
adamc@975 297 | _ => n} 0
adamc@932 298
adamc@470 299 fun reduce file =
adamc@470 300 let
adamc@948 301 val (timpures, impures, absCounts) =
adamc@948 302 foldl (fn ((d, _), (timpures, impures, absCounts)) =>
adamc@916 303 let
adamc@916 304 fun countAbs (e, _) =
adamc@916 305 case e of
adamc@916 306 EAbs (_, _, _, e) => 1 + countAbs e
adamc@916 307 | _ => 0
adamc@916 308 in
adamc@916 309 case d of
adamc@948 310 DDatatype dts =>
adamc@948 311 (if List.exists (fn (_, _, cs) =>
adamc@948 312 List.exists (fn (_, _, NONE) => false
adamc@948 313 | (_, _, SOME t) => simpleTypeImpure timpures t) cs)
adamc@948 314 dts then
adamc@948 315 IS.addList (timpures, map #2 dts)
adamc@948 316 else
adamc@948 317 timpures,
adamc@948 318 impures,
adamc@948 319 absCounts)
adamc@948 320 | DVal (_, n, _, e, _) =>
adamc@948 321 (timpures,
adamc@948 322 if simpleImpure (timpures, impures) E.empty e then
adamc@916 323 IS.add (impures, n)
adamc@916 324 else
adamc@916 325 impures,
adamc@916 326 IM.insert (absCounts, n, countAbs e))
adamc@916 327 | DValRec vis =>
adamc@948 328 (timpures,
adamc@948 329 if List.exists (fn (_, _, _, e, _) => simpleImpure (timpures, impures) E.empty e) vis then
adamc@916 330 foldl (fn ((_, n, _, _, _), impures) =>
adamc@916 331 IS.add (impures, n)) impures vis
adamc@916 332 else
adamc@916 333 impures,
adamc@916 334 foldl (fn ((x, n, _, e, _), absCounts) =>
adamc@916 335 IM.insert (absCounts, n, countAbs e))
adamc@916 336 absCounts vis)
adamc@948 337 | _ => (timpures, impures, absCounts)
adamc@916 338 end)
adamc@948 339 (IS.empty, IS.empty, IM.empty) file
adamc@387 340
adamc@1017 341 val uses = U.File.fold {typ = fn (_, m) => m,
adamc@1017 342 exp = fn (e, m) =>
adamc@1017 343 case e of
adamc@1017 344 ENamed n => IM.insert (m, n, 1 + Option.getOpt (IM.find (m, n), 0))
adamc@1017 345 | _ => m,
adamc@1017 346 decl = fn (_, m) => m}
adamc@1017 347 IM.empty file
adamc@1017 348
adamc@1017 349 val size = U.Exp.fold {typ = fn (_, n) => n,
adamc@1017 350 exp = fn (_, n) => n + 1} 0
adamc@1017 351
adamc@1017 352 fun mayInline (n, e) =
adamc@1017 353 case IM.find (uses, n) of
adamc@1017 354 NONE => false
adamc@1017 355 | SOME count => count <= 1
adamc@1017 356 orelse size e <= Settings.getMonoInline ()
adamc@1017 357
adamc@470 358 fun summarize d (e, _) =
adamc@579 359 let
adamc@579 360 val s =
adamc@579 361 case e of
adamc@579 362 EPrim _ => []
adamc@579 363 | ERel n => if n = d then [UseRel] else []
adamc@579 364 | ENamed _ => []
adamc@579 365 | ECon (_, _, NONE) => []
adamc@579 366 | ECon (_, _, SOME e) => summarize d e
adamc@579 367 | ENone _ => []
adamc@579 368 | ESome (_, e) => summarize d e
adamc@579 369 | EFfi _ => []
adamc@765 370 | EFfiApp (m, x, es) =>
adamc@765 371 if Settings.isEffectful (m, x) then
adamc@765 372 List.concat (map (summarize d) es) @ [Unsure]
adamc@765 373 else
adamc@765 374 List.concat (map (summarize d) es)
adamc@579 375 | EApp ((EFfi _, _), e) => summarize d e
adamc@579 376 | EApp _ =>
adamc@579 377 let
adamc@694 378 fun unravel (e, passed, ls) =
adamc@579 379 case e of
adamc@579 380 ENamed n =>
adamc@579 381 let
adamc@579 382 val ls = rev ls
adamc@579 383 in
adamc@948 384 if IS.member (impures, n) then
adamc@948 385 case IM.find (absCounts, n) of
adamc@948 386 NONE => [Unsure]
adamc@948 387 | SOME len =>
adamc@948 388 if passed < len then
adamc@948 389 ls
adamc@948 390 else
adamc@948 391 ls @ [Unsure]
adamc@948 392 else
adamc@948 393 ls
adamc@579 394 end
adamc@579 395 | ERel n => List.revAppend (ls,
adamc@579 396 if n = d then
adamc@579 397 [UseRel, Unsure]
adamc@579 398 else
adamc@579 399 [Unsure])
adamc@579 400 | EApp (f, x) =>
adamc@995 401 unravel (#1 f, passed + 1, List.revAppend (summarize d x,
adamc@995 402 ls))
adamc@579 403 | _ => [Unsure]
adamc@579 404 in
adamc@694 405 unravel (e, 0, [])
adamc@579 406 end
adamc@252 407
adamc@941 408 | EAbs _ => []
adamc@316 409
adamc@579 410 | EUnop (_, e) => summarize d e
adamc@579 411 | EBinop (_, e1, e2) => summarize d e1 @ summarize d e2
adamc@470 412
adamc@579 413 | ERecord xets => List.concat (map (summarize d o #2) xets)
adamc@579 414 | EField (e, _) => summarize d e
adamc@470 415
adamc@941 416 | ECase (e, pes, _) => summarize d e @ [Unsure]
adamc@941 417 (*let
adamc@579 418 val lss = map (fn (p, e) => summarize (d + patBinds p) e) pes
adamc@579 419 in
adamc@579 420 case lss of
adamc@579 421 [] => raise Fail "Empty pattern match"
adamc@579 422 | ls :: lss =>
adamc@579 423 if List.all (fn ls' => ls' = ls) lss then
adamc@579 424 summarize d e @ ls
adamc@579 425 else
adamc@579 426 [Unsure]
adamc@941 427 end*)
adamc@579 428 | EStrcat (e1, e2) => summarize d e1 @ summarize d e2
adamc@316 429
adamc@579 430 | EError (e, _) => summarize d e @ [Unsure]
adamc@741 431 | EReturnBlob {blob = e1, mimeType = e2, ...} => summarize d e1 @ summarize d e2 @ [Unsure]
adamc@318 432
adamc@579 433 | EWrite e => summarize d e @ [WritePage]
adamc@579 434
adamc@579 435 | ESeq (e1, e2) => summarize d e1 @ summarize d e2
adamc@579 436 | ELet (_, _, e1, e2) => summarize d e1 @ summarize (d + 1) e2
adamc@456 437
adamc@579 438 | EClosure (_, es) => List.concat (map (summarize d) es)
adamc@470 439
adamc@579 440 | EQuery {query, body, initial, ...} =>
adamc@579 441 List.concat [summarize d query,
adamc@579 442 summarize d initial,
adamc@941 443 [ReadDb],
adamc@941 444 summarize (d + 2) body]
adamc@470 445
adamc@579 446 | EDml e => summarize d e @ [WriteDb]
adamc@579 447 | ENextval e => summarize d e @ [WriteDb]
adamc@579 448 | EUnurlify (e, _) => summarize d e
adamc@815 449 | EJavaScript (_, e) => summarize d e
adamc@579 450 | ESignalReturn e => summarize d e
adamc@579 451 | ESignalBind (e1, e2) => summarize d e1 @ summarize d e2
adamc@579 452 | ESignalSource e => summarize d e
adamc@608 453
adamc@1020 454 | EServerCall (e, _, _) => summarize d e @ [Unsure]
adamc@1021 455 | ERecv (e, _) => summarize d e @ [Unsure]
adamc@1021 456 | ESleep e => summarize d e @ [Unsure]
adamc@1021 457 | ESpawn e => summarize d e @ [Unsure]
adamc@579 458 in
adamc@579 459 (*Print.prefaces "Summarize"
adamc@579 460 [("e", MonoPrint.p_exp MonoEnv.empty (e, ErrorMsg.dummySpan)),
adamc@579 461 ("d", Print.PD.string (Int.toString d)),
adamc@579 462 ("s", p_events s)];*)
adamc@579 463 s
adamc@579 464 end
adamc@470 465
adamc@919 466 val impure = fn env => fn e =>
adamc@948 467 simpleImpure (timpures, impures) env e andalso impure e
adamc@916 468 andalso not (List.null (summarize ~1 e))
adamc@916 469
adamc@470 470 fun exp env e =
adamc@470 471 let
adamc@470 472 (*val () = Print.prefaces "exp" [("e", MonoPrint.p_exp env (e, ErrorMsg.dummySpan))]*)
adamc@470 473
adamc@1017 474 fun doLet (x, t, e', b) =
adamc@1017 475 let
adamc@1017 476 fun doSub () =
adamc@1017 477 let
adamc@1017 478 val r = subExpInExp (0, e') b
adamc@1017 479 in
adamc@1017 480 (*Print.prefaces "doSub" [("e'", MonoPrint.p_exp env e'),
adamc@1017 481 ("b", MonoPrint.p_exp (E.pushERel env x t NONE) b),
adamc@1017 482 ("r", MonoPrint.p_exp env r)];*)
adamc@1017 483 #1 (reduceExp env r)
adamc@1017 484 end
adamc@1017 485
adamc@1017 486 fun trySub () =
adamc@1017 487 ((*Print.prefaces "trySub"
adamc@1017 488 [("e", MonoPrint.p_exp env (e, ErrorMsg.dummySpan))];*)
adamc@1017 489 case t of
adamc@1017 490 (TFfi ("Basis", "string"), _) => doSub ()
adamc@1017 491 | (TSignal _, _) => e
adamc@1017 492 | _ =>
adamc@1017 493 case e' of
adamc@1017 494 (ECase _, _) => e
adamc@1017 495 | _ => doSub ())
adamc@1017 496 in
adamc@1017 497 if impure env e' then
adamc@1017 498 let
adamc@1017 499 val effs_e' = summarize 0 e'
adamc@1017 500 val effs_e' = List.filter (fn x => x <> UseRel) effs_e'
adamc@1017 501 val effs_b = summarize 0 b
adamc@1017 502
adamc@1017 503 (*val () = Print.prefaces "Try"
adamc@1017 504 [("e", MonoPrint.p_exp env (e, ErrorMsg.dummySpan)),
adamc@1017 505 ("e'", MonoPrint.p_exp env e'),
adamc@1017 506 ("b", MonoPrint.p_exp (E.pushERel env x t NONE) b),
adamc@1017 507 ("e'_eff", p_events effs_e'),
adamc@1017 508 ("b_eff", p_events effs_b)]*)
adamc@1017 509
adamc@1017 510 fun does eff = List.exists (fn eff' => eff' = eff) effs_e'
adamc@1017 511 val writesPage = does WritePage
adamc@1017 512 val readsDb = does ReadDb
adamc@1017 513 val writesDb = does WriteDb
adamc@1017 514
adamc@1017 515 fun verifyUnused eff =
adamc@1017 516 case eff of
adamc@1017 517 UseRel => false
adamc@1017 518 | _ => true
adamc@1017 519
adamc@1017 520 fun verifyCompatible effs =
adamc@1017 521 case effs of
adamc@1017 522 [] => false
adamc@1017 523 | eff :: effs =>
adamc@1017 524 case eff of
adamc@1017 525 Unsure => false
adamc@1017 526 | UseRel => List.all verifyUnused effs
adamc@1017 527 | WritePage => not writesPage andalso verifyCompatible effs
adamc@1017 528 | ReadDb => not writesDb andalso verifyCompatible effs
adamc@1017 529 | WriteDb => not writesDb andalso not readsDb andalso verifyCompatible effs
adamc@1017 530 in
adamc@1017 531 (*Print.prefaces "verifyCompatible"
adamc@1017 532 [("e'", MonoPrint.p_exp env e'),
adamc@1017 533 ("b", MonoPrint.p_exp (E.pushERel env x t NONE) b),
adamc@1017 534 ("effs_e'", Print.p_list p_event effs_e'),
adamc@1017 535 ("effs_b", Print.p_list p_event effs_b)];*)
adamc@1017 536 if (List.null effs_e'
adamc@1017 537 orelse (List.all (fn eff => eff <> Unsure) effs_e'
adamc@1017 538 andalso verifyCompatible effs_b)
adamc@1017 539 orelse (case effs_b of
adamc@1017 540 UseRel :: effs => List.all verifyUnused effs
adamc@1017 541 | _ => false))
adamc@1017 542 andalso countFree 0 0 b = 1
adamc@1017 543 andalso not (freeInAbs b) then
adamc@1017 544 trySub ()
adamc@1017 545 else
adamc@1017 546 e
adamc@1017 547 end
adamc@1017 548 else
adamc@1017 549 trySub ()
adamc@1017 550 end
adamc@1017 551
adamc@470 552 val r =
adamc@470 553 case e of
adamc@470 554 ERel n =>
adamc@470 555 (case E.lookupERel env n of
adamc@470 556 (_, _, SOME e') => #1 e'
adamc@470 557 | _ => e)
adamc@470 558 | ENamed n =>
adamc@470 559 (case E.lookupENamed env n of
adamc@470 560 (_, _, SOME e', _) => ((*Print.prefaces "Switch" [("n", Print.PD.string (Int.toString n)),
adamc@470 561 ("e'", MonoPrint.p_exp env e')];*)
adamc@470 562 #1 e')
adamc@470 563 | _ => e)
adamc@470 564
adamc@470 565 | EApp ((EAbs (x, t, _, e1), loc), e2) =>
adamc@470 566 ((*Print.prefaces "Considering" [("e1", MonoPrint.p_exp (E.pushERel env x t NONE) e1),
adamc@694 567 ("e2", MonoPrint.p_exp env e2),
adamc@694 568 ("sub", MonoPrint.p_exp env (reduceExp env (subExpInExp (0, e2) e1)))];*)
adamc@975 569 if impure env e2 orelse countFree 0 0 e1 > 1 then
adamc@470 570 #1 (reduceExp env (ELet (x, t, e2, e1), loc))
adamc@470 571 else
adamc@470 572 #1 (reduceExp env (subExpInExp (0, e2) e1)))
adamc@470 573
adamc@470 574 | ECase (e', pes, {disc, result}) =>
adamc@442 575 let
adamc@470 576 fun push () =
adamc@470 577 case result of
adamc@470 578 (TFun (dom, result), loc) =>
adamc@470 579 if List.all (fn (_, (EAbs _, _)) => true | _ => false) pes then
adamc@827 580 let
adamc@827 581 val r =
adamc@827 582 EAbs ("y", dom, result,
adamc@827 583 (ECase (liftExpInExp 0 e',
adamc@827 584 map (fn (p, (EAbs (_, _, _, e), _)) =>
adamc@827 585 (p, swapExpVarsPat (0, patBinds p) e)
adamc@827 586 | _ => raise Fail "MonoReduce ECase") pes,
adamc@827 587 {disc = disc, result = result}), loc))
adamc@827 588 in
adamc@827 589 (*Print.prefaces "Swapped"
adamc@827 590 [("e", MonoPrint.p_exp env (e, ErrorMsg.dummySpan)),
adamc@827 591 ("r", MonoPrint.p_exp env (r, ErrorMsg.dummySpan))];*)
adamc@827 592 r
adamc@827 593 end
adamc@470 594 else
adamc@470 595 e
adamc@470 596 | _ => e
adamc@318 597
adamc@470 598 fun search pes =
adamc@470 599 case pes of
adamc@470 600 [] => push ()
adamc@470 601 | (p, body) :: pes =>
adamc@814 602 case match ([], p, e') of
adamc@470 603 No => search pes
adamc@470 604 | Maybe => push ()
adamc@814 605 | Yes subs =>
adamc@800 606 let
adamc@829 607 val (body, remaining) =
adamc@829 608 foldl (fn (e, (body, remaining)) =>
adamc@829 609 (subExpInExp (0, multiLift remaining e) body, remaining - 1))
adamc@829 610 (body, length subs - 1) subs
adamc@920 611 val r = reduceExp (E.patBinds env p) body
adamc@800 612 in
adamc@829 613 (*Print.preface ("subs", Print.p_list (MonoPrint.p_exp env) subs);*)
adamc@800 614 (*Print.prefaces "ECase"
adamc@829 615 [("old", MonoPrint.p_exp env body),
adamc@829 616 ("body", MonoPrint.p_exp env body),
adamc@800 617 ("r", MonoPrint.p_exp env r)];*)
adamc@800 618 #1 r
adamc@800 619 end
adamc@470 620 in
adamc@941 621 if impure env e' then
adamc@941 622 e
adamc@941 623 else
adamc@941 624 search pes
adamc@470 625 end
adamc@318 626
adamc@470 627 | EField ((ERecord xes, _), x) =>
adamc@470 628 (case List.find (fn (x', _, _) => x' = x) xes of
adamc@470 629 SOME (_, e, _) => #1 e
adamc@470 630 | NONE => e)
adamc@398 631
adamc@470 632 | ELet (x1, t1, (ELet (x2, t2, e1, b1), loc), b2) =>
adamc@470 633 let
adamc@470 634 val e' = (ELet (x2, t2, e1,
adamc@470 635 (ELet (x1, t1, b1,
adamc@470 636 liftExpInExp 1 b2), loc)), loc)
adamc@442 637 in
adamc@470 638 (*Print.prefaces "ELet commute" [("e", MonoPrint.p_exp env (e, loc)),
adamc@470 639 ("e'", MonoPrint.p_exp env e')];*)
adamc@470 640 #1 (reduceExp env e')
adamc@470 641 end
adamc@470 642 | EApp ((ELet (x, t, e, b), loc), e') =>
adamc@470 643 #1 (reduceExp env (ELet (x, t, e,
adamc@470 644 (EApp (b, liftExpInExp 0 e'), loc)), loc))
adamc@470 645
adamc@1017 646 | ELet (x, t, e', b as (EAbs (x', t' as (TRecord [], _), ran, e''), loc)) =>
adamc@919 647 if impure env e' then
adamc@1017 648 doLet (x, t, e', b)
adamc@848 649 else
adamc@920 650 EAbs (x', t', ran, reduceExp (E.pushERel env x' t' NONE)
adamc@920 651 (ELet (x, t, liftExpInExp 0 e', swapExpVars 0 e''), loc))
adamc@470 652
adamc@1017 653 | ELet (x, t, e', b) => doLet (x, t, e', b)
adamc@252 654
adamc@470 655 | EStrcat ((EPrim (Prim.String s1), _), (EPrim (Prim.String s2), _)) =>
adamc@470 656 EPrim (Prim.String (s1 ^ s2))
adamc@268 657
adamc@572 658 | ESignalBind ((ESignalReturn e1, loc), e2) =>
adamc@572 659 #1 (reduceExp env (EApp (e2, e1), loc))
adamc@572 660
adamc@470 661 | _ => e
adamc@470 662 in
adamc@829 663 (*Print.prefaces "exp'" [("e", MonoPrint.p_exp env (e, ErrorMsg.dummySpan)),
adamc@829 664 ("r", MonoPrint.p_exp env (r, ErrorMsg.dummySpan))];*)
adamc@470 665 r
adamc@470 666 end
adamc@470 667
adamc@470 668 and bind (env, b) =
adamc@470 669 case b of
adamc@470 670 U.Decl.Datatype (x, n, xncs) => E.pushDatatype env x n xncs
adamc@470 671 | U.Decl.RelE (x, t) => E.pushERel env x t NONE
adamc@1017 672 | U.Decl.NamedE (x, n, t, eo, s) =>
adamc@1017 673 let
adamc@1017 674 val eo = case eo of
adamc@1017 675 NONE => NONE
adamc@1017 676 | SOME e => if mayInline (n, e) then
adamc@1017 677 SOME e
adamc@1017 678 else
adamc@1017 679 NONE
adamc@1017 680 in
adamc@1017 681 E.pushENamed env x n t (Option.map (reduceExp env) eo) s
adamc@1017 682 end
adamc@470 683
adamc@470 684 and reduceExp env = U.Exp.mapB {typ = typ, exp = exp, bind = bind} env
adamc@470 685
adamc@801 686 fun decl env d = ((*Print.preface ("d", MonoPrint.p_decl env (d, ErrorMsg.dummySpan));*)
adamc@801 687 d)
adamc@398 688 in
adamc@470 689 U.File.mapB {typ = typ, exp = exp, decl = decl, bind = bind} E.empty file
adamc@398 690 end
adamc@133 691
adamc@133 692 end