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annotate src/mono_reduce.sml @ 948:b03d48aac959

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Find more opportunities for 'let' inlining with better purity information
author Adam Chlipala <adamc@hcoop.net>
date Thu, 17 Sep 2009 12:55:22 -0400
parents b8d7a47b8e0c
children 8fe576c0bee9
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@252 115
adamc@252 116 val liftExpInExp = Monoize.liftExpInExp
adamc@252 117
adamc@829 118 fun multiLift n e =
adamc@829 119 case n of
adamc@829 120 0 => e
adamc@829 121 | _ => multiLift (n - 1) (liftExpInExp 0 e)
adamc@829 122
adamc@252 123 val subExpInExp' =
adamc@133 124 U.Exp.mapB {typ = fn t => t,
adamc@133 125 exp = fn (xn, rep) => fn e =>
adamc@133 126 case e of
adamc@133 127 ERel xn' =>
adamc@133 128 (case Int.compare (xn', xn) of
adamc@133 129 EQUAL => #1 rep
adamc@133 130 | GREATER=> ERel (xn' - 1)
adamc@133 131 | LESS => e)
adamc@133 132 | _ => e,
adamc@133 133 bind = fn ((xn, rep), U.Exp.RelE _) => (xn+1, liftExpInExp 0 rep)
adamc@133 134 | (ctx, _) => ctx}
adamc@133 135
adamc@252 136 fun subExpInExp (n, e1) e2 =
adamc@252 137 let
adamc@252 138 val r = subExpInExp' (n, e1) e2
adamc@252 139 in
adamc@252 140 (*Print.prefaces "subExpInExp" [("e1", MonoPrint.p_exp MonoEnv.empty e1),
adamc@252 141 ("e2", MonoPrint.p_exp MonoEnv.empty e2),
adamc@252 142 ("r", MonoPrint.p_exp MonoEnv.empty r)];*)
adamc@252 143 r
adamc@252 144 end
adamc@133 145
adamc@133 146 fun typ c = c
adamc@133 147
adamc@316 148 val swapExpVars =
adamc@316 149 U.Exp.mapB {typ = fn t => t,
adamc@316 150 exp = fn lower => fn e =>
adamc@316 151 case e of
adamc@316 152 ERel xn =>
adamc@316 153 if xn = lower then
adamc@316 154 ERel (lower + 1)
adamc@316 155 else if xn = lower + 1 then
adamc@316 156 ERel lower
adamc@316 157 else
adamc@316 158 e
adamc@316 159 | _ => e,
adamc@316 160 bind = fn (lower, U.Exp.RelE _) => lower+1
adamc@316 161 | (lower, _) => lower}
adamc@316 162
adamc@341 163 val swapExpVarsPat =
adamc@341 164 U.Exp.mapB {typ = fn t => t,
adamc@341 165 exp = fn (lower, len) => fn e =>
adamc@341 166 case e of
adamc@341 167 ERel xn =>
adamc@341 168 if xn = lower then
adamc@827 169 ERel (lower + len)
adamc@341 170 else if xn >= lower + 1 andalso xn < lower + 1 + len then
adamc@341 171 ERel (xn - 1)
adamc@341 172 else
adamc@341 173 e
adamc@341 174 | _ => e,
adamc@341 175 bind = fn ((lower, len), U.Exp.RelE _) => (lower+1, len)
adamc@341 176 | (st, _) => st}
adamc@341 177
adamc@814 178 datatype result = Yes of exp list | No | Maybe
adamc@258 179
adamc@183 180 fun match (env, p : pat, e : exp) =
adamc@183 181 case (#1 p, #1 e) of
adamc@258 182 (PWild, _) => Yes env
adamc@814 183 | (PVar (x, t), _) => Yes (e :: env)
adamc@183 184
adamc@280 185 | (PPrim (Prim.String s), EStrcat ((EPrim (Prim.String s'), _), _)) =>
adamc@280 186 if String.isPrefix s' s then
adamc@280 187 Maybe
adamc@280 188 else
adamc@280 189 No
adamc@280 190
adamc@183 191 | (PPrim p, EPrim p') =>
adamc@183 192 if Prim.equal (p, p') then
adamc@258 193 Yes env
adamc@183 194 else
adamc@258 195 No
adamc@183 196
adamc@188 197 | (PCon (_, PConVar n1, NONE), ECon (_, PConVar n2, NONE)) =>
adamc@183 198 if n1 = n2 then
adamc@258 199 Yes env
adamc@183 200 else
adamc@258 201 No
adamc@183 202
adamc@188 203 | (PCon (_, PConVar n1, SOME p), ECon (_, PConVar n2, SOME e)) =>
adamc@183 204 if n1 = n2 then
adamc@183 205 match (env, p, e)
adamc@183 206 else
adamc@258 207 No
adamc@183 208
adamc@188 209 | (PCon (_, PConFfi {mod = m1, con = con1, ...}, NONE), ECon (_, PConFfi {mod = m2, con = con2, ...}, NONE)) =>
adamc@185 210 if m1 = m2 andalso con1 = con2 then
adamc@258 211 Yes env
adamc@185 212 else
adamc@258 213 No
adamc@185 214
adamc@188 215 | (PCon (_, PConFfi {mod = m1, con = con1, ...}, SOME ep), ECon (_, PConFfi {mod = m2, con = con2, ...}, SOME e)) =>
adamc@185 216 if m1 = m2 andalso con1 = con2 then
adamc@185 217 match (env, p, e)
adamc@185 218 else
adamc@258 219 No
adamc@185 220
adamc@183 221 | (PRecord xps, ERecord xes) =>
adamc@183 222 let
adamc@183 223 fun consider (xps, env) =
adamc@183 224 case xps of
adamc@258 225 [] => Yes env
adamc@183 226 | (x, p, _) :: rest =>
adamc@183 227 case List.find (fn (x', _, _) => x' = x) xes of
adamc@258 228 NONE => No
adamc@183 229 | SOME (_, e, _) =>
adamc@183 230 case match (env, p, e) of
adamc@258 231 No => No
adamc@258 232 | Maybe => Maybe
adamc@258 233 | Yes env => consider (rest, env)
adamc@183 234 in
adamc@183 235 consider (xps, env)
adamc@183 236 end
adamc@183 237
adamc@726 238 | (PNone _, ENone _) => Yes env
adamc@921 239 | (PNone _, ESome _) => No
adamc@726 240 | (PSome (_, p), ESome (_, e)) => match (env, p, e)
adamc@921 241 | (PSome _, ENone _) => No
adamc@726 242
adamc@258 243 | _ => Maybe
adamc@183 244
adamc@318 245 datatype event =
adamc@318 246 WritePage
adamc@318 247 | ReadDb
adamc@318 248 | WriteDb
adamc@481 249 | UseRel
adamc@318 250 | Unsure
adamc@318 251
adamc@318 252 fun p_event e =
adamc@318 253 let
adamc@318 254 open Print.PD
adamc@318 255 in
adamc@318 256 case e of
adamc@318 257 WritePage => string "WritePage"
adamc@318 258 | ReadDb => string "ReadDb"
adamc@318 259 | WriteDb => string "WriteDb"
adamc@481 260 | UseRel => string "UseRel"
adamc@318 261 | Unsure => string "Unsure"
adamc@318 262 end
adamc@318 263
adamc@470 264 val p_events = Print.p_list p_event
adamc@470 265
adamc@318 266 fun patBinds (p, _) =
adamc@318 267 case p of
adamc@318 268 PWild => 0
adamc@318 269 | PVar _ => 1
adamc@318 270 | PPrim _ => 0
adamc@318 271 | PCon (_, _, NONE) => 0
adamc@318 272 | PCon (_, _, SOME p) => patBinds p
adamc@318 273 | PRecord xpts => foldl (fn ((_, p, _), n) => n + patBinds p) 0 xpts
adamc@318 274 | PNone _ => 0
adamc@318 275 | PSome (_, p) => patBinds p
adamc@318 276
adamc@932 277 val countFree = U.Exp.foldB {typ = fn (_, n) => n,
adamc@932 278 exp = fn (x, e, n) =>
adamc@932 279 case e of
adamc@932 280 ERel x' => if x = x' then n + 1 else n
adamc@932 281 | _ => n,
adamc@932 282 bind = fn (n, b) =>
adamc@932 283 case b of
adamc@932 284 U.Exp.RelE _ => n + 1
adamc@932 285 | _ => n} 0 0
adamc@932 286
adamc@470 287 fun reduce file =
adamc@470 288 let
adamc@948 289 val (timpures, impures, absCounts) =
adamc@948 290 foldl (fn ((d, _), (timpures, impures, absCounts)) =>
adamc@916 291 let
adamc@916 292 fun countAbs (e, _) =
adamc@916 293 case e of
adamc@916 294 EAbs (_, _, _, e) => 1 + countAbs e
adamc@916 295 | _ => 0
adamc@916 296 in
adamc@916 297 case d of
adamc@948 298 DDatatype dts =>
adamc@948 299 (if List.exists (fn (_, _, cs) =>
adamc@948 300 List.exists (fn (_, _, NONE) => false
adamc@948 301 | (_, _, SOME t) => simpleTypeImpure timpures t) cs)
adamc@948 302 dts then
adamc@948 303 IS.addList (timpures, map #2 dts)
adamc@948 304 else
adamc@948 305 timpures,
adamc@948 306 impures,
adamc@948 307 absCounts)
adamc@948 308 | DVal (_, n, _, e, _) =>
adamc@948 309 (timpures,
adamc@948 310 if simpleImpure (timpures, impures) E.empty e then
adamc@916 311 IS.add (impures, n)
adamc@916 312 else
adamc@916 313 impures,
adamc@916 314 IM.insert (absCounts, n, countAbs e))
adamc@916 315 | DValRec vis =>
adamc@948 316 (timpures,
adamc@948 317 if List.exists (fn (_, _, _, e, _) => simpleImpure (timpures, impures) E.empty e) vis then
adamc@916 318 foldl (fn ((_, n, _, _, _), impures) =>
adamc@916 319 IS.add (impures, n)) impures vis
adamc@916 320 else
adamc@916 321 impures,
adamc@916 322 foldl (fn ((x, n, _, e, _), absCounts) =>
adamc@916 323 IM.insert (absCounts, n, countAbs e))
adamc@916 324 absCounts vis)
adamc@948 325 | _ => (timpures, impures, absCounts)
adamc@916 326 end)
adamc@948 327 (IS.empty, IS.empty, IM.empty) file
adamc@387 328
adamc@470 329 fun summarize d (e, _) =
adamc@579 330 let
adamc@579 331 val s =
adamc@579 332 case e of
adamc@579 333 EPrim _ => []
adamc@579 334 | ERel n => if n = d then [UseRel] else []
adamc@579 335 | ENamed _ => []
adamc@579 336 | ECon (_, _, NONE) => []
adamc@579 337 | ECon (_, _, SOME e) => summarize d e
adamc@579 338 | ENone _ => []
adamc@579 339 | ESome (_, e) => summarize d e
adamc@579 340 | EFfi _ => []
adamc@765 341 | EFfiApp (m, x, es) =>
adamc@765 342 if Settings.isEffectful (m, x) then
adamc@765 343 List.concat (map (summarize d) es) @ [Unsure]
adamc@765 344 else
adamc@765 345 List.concat (map (summarize d) es)
adamc@579 346 | EApp ((EFfi _, _), e) => summarize d e
adamc@579 347 | EApp _ =>
adamc@579 348 let
adamc@694 349 fun unravel (e, passed, ls) =
adamc@579 350 case e of
adamc@579 351 ENamed n =>
adamc@579 352 let
adamc@579 353 val ls = rev ls
adamc@579 354 in
adamc@948 355 if IS.member (impures, n) then
adamc@948 356 case IM.find (absCounts, n) of
adamc@948 357 NONE => [Unsure]
adamc@948 358 | SOME len =>
adamc@948 359 if passed < len then
adamc@948 360 ls
adamc@948 361 else
adamc@948 362 ls @ [Unsure]
adamc@948 363 else
adamc@948 364 ls
adamc@579 365 end
adamc@579 366 | ERel n => List.revAppend (ls,
adamc@579 367 if n = d then
adamc@579 368 [UseRel, Unsure]
adamc@579 369 else
adamc@579 370 [Unsure])
adamc@579 371 | EApp (f, x) =>
adamc@694 372 unravel (#1 f, passed + 1, summarize d x @ ls)
adamc@579 373 | _ => [Unsure]
adamc@579 374 in
adamc@694 375 unravel (e, 0, [])
adamc@579 376 end
adamc@252 377
adamc@941 378 | EAbs _ => []
adamc@316 379
adamc@579 380 | EUnop (_, e) => summarize d e
adamc@579 381 | EBinop (_, e1, e2) => summarize d e1 @ summarize d e2
adamc@470 382
adamc@579 383 | ERecord xets => List.concat (map (summarize d o #2) xets)
adamc@579 384 | EField (e, _) => summarize d e
adamc@470 385
adamc@941 386 | ECase (e, pes, _) => summarize d e @ [Unsure]
adamc@941 387 (*let
adamc@579 388 val lss = map (fn (p, e) => summarize (d + patBinds p) e) pes
adamc@579 389 in
adamc@579 390 case lss of
adamc@579 391 [] => raise Fail "Empty pattern match"
adamc@579 392 | ls :: lss =>
adamc@579 393 if List.all (fn ls' => ls' = ls) lss then
adamc@579 394 summarize d e @ ls
adamc@579 395 else
adamc@579 396 [Unsure]
adamc@941 397 end*)
adamc@579 398 | EStrcat (e1, e2) => summarize d e1 @ summarize d e2
adamc@316 399
adamc@579 400 | EError (e, _) => summarize d e @ [Unsure]
adamc@741 401 | EReturnBlob {blob = e1, mimeType = e2, ...} => summarize d e1 @ summarize d e2 @ [Unsure]
adamc@318 402
adamc@579 403 | EWrite e => summarize d e @ [WritePage]
adamc@579 404
adamc@579 405 | ESeq (e1, e2) => summarize d e1 @ summarize d e2
adamc@579 406 | ELet (_, _, e1, e2) => summarize d e1 @ summarize (d + 1) e2
adamc@456 407
adamc@579 408 | EClosure (_, es) => List.concat (map (summarize d) es)
adamc@470 409
adamc@579 410 | EQuery {query, body, initial, ...} =>
adamc@579 411 List.concat [summarize d query,
adamc@579 412 summarize d initial,
adamc@941 413 [ReadDb],
adamc@941 414 summarize (d + 2) body]
adamc@470 415
adamc@579 416 | EDml e => summarize d e @ [WriteDb]
adamc@579 417 | ENextval e => summarize d e @ [WriteDb]
adamc@579 418 | EUnurlify (e, _) => summarize d e
adamc@815 419 | EJavaScript (_, e) => summarize d e
adamc@579 420 | ESignalReturn e => summarize d e
adamc@579 421 | ESignalBind (e1, e2) => summarize d e1 @ summarize d e2
adamc@579 422 | ESignalSource e => summarize d e
adamc@608 423
adamc@941 424 | EServerCall (e, _, _, _) => summarize d e @ [Unsure]
adamc@941 425 | ERecv (e, _, _) => summarize d e @ [Unsure]
adamc@941 426 | ESleep (e, _) => summarize d e @ [Unsure]
adamc@579 427 in
adamc@579 428 (*Print.prefaces "Summarize"
adamc@579 429 [("e", MonoPrint.p_exp MonoEnv.empty (e, ErrorMsg.dummySpan)),
adamc@579 430 ("d", Print.PD.string (Int.toString d)),
adamc@579 431 ("s", p_events s)];*)
adamc@579 432 s
adamc@579 433 end
adamc@470 434
adamc@919 435 val impure = fn env => fn e =>
adamc@948 436 simpleImpure (timpures, impures) env e andalso impure e
adamc@916 437 andalso not (List.null (summarize ~1 e))
adamc@916 438
adamc@470 439 fun exp env e =
adamc@470 440 let
adamc@470 441 (*val () = Print.prefaces "exp" [("e", MonoPrint.p_exp env (e, ErrorMsg.dummySpan))]*)
adamc@470 442
adamc@470 443 val r =
adamc@470 444 case e of
adamc@470 445 ERel n =>
adamc@470 446 (case E.lookupERel env n of
adamc@470 447 (_, _, SOME e') => #1 e'
adamc@470 448 | _ => e)
adamc@470 449 | ENamed n =>
adamc@470 450 (case E.lookupENamed env n of
adamc@470 451 (_, _, SOME e', _) => ((*Print.prefaces "Switch" [("n", Print.PD.string (Int.toString n)),
adamc@470 452 ("e'", MonoPrint.p_exp env e')];*)
adamc@470 453 #1 e')
adamc@470 454 | _ => e)
adamc@470 455
adamc@470 456 | EApp ((EAbs (x, t, _, e1), loc), e2) =>
adamc@470 457 ((*Print.prefaces "Considering" [("e1", MonoPrint.p_exp (E.pushERel env x t NONE) e1),
adamc@694 458 ("e2", MonoPrint.p_exp env e2),
adamc@694 459 ("sub", MonoPrint.p_exp env (reduceExp env (subExpInExp (0, e2) e1)))];*)
adamc@932 460 if impure env e2 orelse countFree e1 > 1 then
adamc@470 461 #1 (reduceExp env (ELet (x, t, e2, e1), loc))
adamc@470 462 else
adamc@470 463 #1 (reduceExp env (subExpInExp (0, e2) e1)))
adamc@470 464
adamc@470 465 | ECase (e', pes, {disc, result}) =>
adamc@442 466 let
adamc@470 467 fun push () =
adamc@470 468 case result of
adamc@470 469 (TFun (dom, result), loc) =>
adamc@470 470 if List.all (fn (_, (EAbs _, _)) => true | _ => false) pes then
adamc@827 471 let
adamc@827 472 val r =
adamc@827 473 EAbs ("y", dom, result,
adamc@827 474 (ECase (liftExpInExp 0 e',
adamc@827 475 map (fn (p, (EAbs (_, _, _, e), _)) =>
adamc@827 476 (p, swapExpVarsPat (0, patBinds p) e)
adamc@827 477 | _ => raise Fail "MonoReduce ECase") pes,
adamc@827 478 {disc = disc, result = result}), loc))
adamc@827 479 in
adamc@827 480 (*Print.prefaces "Swapped"
adamc@827 481 [("e", MonoPrint.p_exp env (e, ErrorMsg.dummySpan)),
adamc@827 482 ("r", MonoPrint.p_exp env (r, ErrorMsg.dummySpan))];*)
adamc@827 483 r
adamc@827 484 end
adamc@470 485 else
adamc@470 486 e
adamc@470 487 | _ => e
adamc@318 488
adamc@470 489 fun search pes =
adamc@470 490 case pes of
adamc@470 491 [] => push ()
adamc@470 492 | (p, body) :: pes =>
adamc@814 493 case match ([], p, e') of
adamc@470 494 No => search pes
adamc@470 495 | Maybe => push ()
adamc@814 496 | Yes subs =>
adamc@800 497 let
adamc@829 498 val (body, remaining) =
adamc@829 499 foldl (fn (e, (body, remaining)) =>
adamc@829 500 (subExpInExp (0, multiLift remaining e) body, remaining - 1))
adamc@829 501 (body, length subs - 1) subs
adamc@920 502 val r = reduceExp (E.patBinds env p) body
adamc@800 503 in
adamc@829 504 (*Print.preface ("subs", Print.p_list (MonoPrint.p_exp env) subs);*)
adamc@800 505 (*Print.prefaces "ECase"
adamc@829 506 [("old", MonoPrint.p_exp env body),
adamc@829 507 ("body", MonoPrint.p_exp env body),
adamc@800 508 ("r", MonoPrint.p_exp env r)];*)
adamc@800 509 #1 r
adamc@800 510 end
adamc@470 511 in
adamc@941 512 if impure env e' then
adamc@941 513 e
adamc@941 514 else
adamc@941 515 search pes
adamc@470 516 end
adamc@318 517
adamc@470 518 | EField ((ERecord xes, _), x) =>
adamc@470 519 (case List.find (fn (x', _, _) => x' = x) xes of
adamc@470 520 SOME (_, e, _) => #1 e
adamc@470 521 | NONE => e)
adamc@398 522
adamc@470 523 | ELet (x1, t1, (ELet (x2, t2, e1, b1), loc), b2) =>
adamc@470 524 let
adamc@470 525 val e' = (ELet (x2, t2, e1,
adamc@470 526 (ELet (x1, t1, b1,
adamc@470 527 liftExpInExp 1 b2), loc)), loc)
adamc@442 528 in
adamc@470 529 (*Print.prefaces "ELet commute" [("e", MonoPrint.p_exp env (e, loc)),
adamc@470 530 ("e'", MonoPrint.p_exp env e')];*)
adamc@470 531 #1 (reduceExp env e')
adamc@470 532 end
adamc@470 533 | EApp ((ELet (x, t, e, b), loc), e') =>
adamc@470 534 #1 (reduceExp env (ELet (x, t, e,
adamc@470 535 (EApp (b, liftExpInExp 0 e'), loc)), loc))
adamc@470 536
adamc@470 537 | ELet (x, t, e', (EAbs (x', t' as (TRecord [], _), ran, e''), loc)) =>
adamc@919 538 if impure env e' then
adamc@848 539 e
adamc@848 540 else
adamc@920 541 EAbs (x', t', ran, reduceExp (E.pushERel env x' t' NONE)
adamc@920 542 (ELet (x, t, liftExpInExp 0 e', swapExpVars 0 e''), loc))
adamc@470 543
adamc@470 544 | ELet (x, t, e', b) =>
adamc@470 545 let
adamc@470 546 fun doSub () =
adamc@800 547 let
adamc@800 548 val r = subExpInExp (0, e') b
adamc@800 549 in
adamc@800 550 (*Print.prefaces "doSub" [("e'", MonoPrint.p_exp env e'),
adamc@941 551 ("b", MonoPrint.p_exp (E.pushERel env x t NONE) b),
adamc@941 552 ("r", MonoPrint.p_exp env r)];*)
adamc@800 553 #1 (reduceExp env r)
adamc@800 554 end
adamc@470 555
adamc@470 556 fun trySub () =
adamc@916 557 ((*Print.prefaces "trySub"
adamc@916 558 [("e", MonoPrint.p_exp env (e, ErrorMsg.dummySpan))];*)
adamc@916 559 case t of
adamc@916 560 (TFfi ("Basis", "string"), _) => doSub ()
adamc@916 561 | (TSignal _, _) => e
adamc@916 562 | _ =>
adamc@916 563 case e' of
adamc@916 564 (ECase _, _) => e
adamc@916 565 | _ => doSub ())
adamc@470 566 in
adamc@919 567 if impure env e' then
adamc@470 568 let
adamc@470 569 val effs_e' = summarize 0 e'
adamc@489 570 val effs_e' = List.filter (fn x => x <> UseRel) effs_e'
adamc@470 571 val effs_b = summarize 0 b
adamc@470 572
adamc@470 573 (*val () = Print.prefaces "Try"
adamc@921 574 [(*("e", MonoPrint.p_exp env (e, ErrorMsg.dummySpan)),*)
adamc@916 575 ("e'", MonoPrint.p_exp env e'),
adamc@916 576 ("e'_eff", p_events effs_e'),
adamc@489 577 ("b", p_events effs_b)]*)
adamc@470 578
adamc@470 579 fun does eff = List.exists (fn eff' => eff' = eff) effs_e'
adamc@470 580 val writesPage = does WritePage
adamc@470 581 val readsDb = does ReadDb
adamc@470 582 val writesDb = does WriteDb
adamc@470 583
adamc@470 584 fun verifyUnused eff =
adamc@470 585 case eff of
adamc@481 586 UseRel => false
adamc@470 587 | _ => true
adamc@470 588
adamc@470 589 fun verifyCompatible effs =
adamc@470 590 case effs of
adamc@470 591 [] => false
adamc@470 592 | eff :: effs =>
adamc@470 593 case eff of
adamc@470 594 Unsure => false
adamc@481 595 | UseRel => List.all verifyUnused effs
adamc@470 596 | WritePage => not writesPage andalso verifyCompatible effs
adamc@470 597 | ReadDb => not writesDb andalso verifyCompatible effs
adamc@470 598 | WriteDb => not writesDb andalso not readsDb andalso verifyCompatible effs
adamc@470 599 in
adamc@470 600 (*Print.prefaces "verifyCompatible"
adamc@601 601 [("e'", MonoPrint.p_exp env e'),
adamc@601 602 ("b", MonoPrint.p_exp (E.pushERel env x t NONE) b),
adamc@601 603 ("effs_e'", Print.p_list p_event effs_e'),
adamc@601 604 ("effs_b", Print.p_list p_event effs_b)];*)
adamc@941 605 if (List.null effs_e'
adamc@941 606 orelse (List.all (fn eff => eff <> Unsure) effs_e'
adamc@941 607 andalso verifyCompatible effs_b)
adamc@941 608 orelse (case effs_b of
adamc@941 609 UseRel :: effs => List.all verifyUnused effs
adamc@941 610 | _ => false))
adamc@941 611 andalso countFree b = 1 then
adamc@470 612 trySub ()
adamc@470 613 else
adamc@470 614 e
adamc@470 615 end
adamc@470 616 else
adamc@442 617 trySub ()
adamc@442 618 end
adamc@252 619
adamc@470 620 | EStrcat ((EPrim (Prim.String s1), _), (EPrim (Prim.String s2), _)) =>
adamc@470 621 EPrim (Prim.String (s1 ^ s2))
adamc@268 622
adamc@572 623 | ESignalBind ((ESignalReturn e1, loc), e2) =>
adamc@572 624 #1 (reduceExp env (EApp (e2, e1), loc))
adamc@572 625
adamc@470 626 | _ => e
adamc@470 627 in
adamc@829 628 (*Print.prefaces "exp'" [("e", MonoPrint.p_exp env (e, ErrorMsg.dummySpan)),
adamc@829 629 ("r", MonoPrint.p_exp env (r, ErrorMsg.dummySpan))];*)
adamc@470 630 r
adamc@470 631 end
adamc@470 632
adamc@470 633 and bind (env, b) =
adamc@470 634 case b of
adamc@470 635 U.Decl.Datatype (x, n, xncs) => E.pushDatatype env x n xncs
adamc@470 636 | U.Decl.RelE (x, t) => E.pushERel env x t NONE
adamc@470 637 | U.Decl.NamedE (x, n, t, eo, s) => E.pushENamed env x n t (Option.map (reduceExp env) eo) s
adamc@470 638
adamc@470 639 and reduceExp env = U.Exp.mapB {typ = typ, exp = exp, bind = bind} env
adamc@470 640
adamc@801 641 fun decl env d = ((*Print.preface ("d", MonoPrint.p_decl env (d, ErrorMsg.dummySpan));*)
adamc@801 642 d)
adamc@398 643 in
adamc@470 644 U.File.mapB {typ = typ, exp = exp, decl = decl, bind = bind} E.empty file
adamc@398 645 end
adamc@133 646
adamc@133 647 end