1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
|
/* NSC -- new Scala compiler
* Copyright 2005-2012 LAMP/EPFL
* @author Iulian Dragos
*/
package scala.tools.nsc
package transform
import scala.tools.nsc.symtab.Flags
import scala.collection.{ mutable, immutable }
import scala.language.postfixOps
import scala.language.existentials
/** Specialize code on types.
*
* Make sure you've read the thesis:
*
* Iulian Dragos: Compiling Scala for Performance (chapter 4)
*
* There are some things worth noting, (possibly) not mentioned there:
* 0) Make sure you understand the meaning of various `SpecializedInfo` descriptors
* defined below.
*
* 1) Specializing traits by introducing bridges in specialized methods
* of the specialized trait may introduce problems during mixin composition.
* Concretely, it may cause cyclic calls and result in a stack overflow.
* See ticket #4351.
* This was solved by introducing an `Abstract` specialized info descriptor.
* Instead of generating a bridge in the trait, an abstract method is generated.
*
* 2) Specialized private members sometimes have to be switched to protected.
* In some cases, even this is not enough. Example:
*
* {{{
* class A[@specialized T](protected val d: T) {
* def foo(that: A[T]) = that.d
* }
* }}}
*
* Specialization will generate a specialized class and a specialized method:
*
* {{{
* class A$mcI$sp(protected val d: Int) extends A[Int] {
* def foo(that: A[Int]) = foo$mcI$sp(that)
* def foo(that: A[Int]) = that.d
* }
* }}}
*
* Above, `A$mcI$sp` cannot access `d`, so the method cannot be typechecked.
*/
abstract class SpecializeTypes extends InfoTransform with TypingTransformers {
import global._
import Flags._
/** the name of the phase: */
val phaseName: String = "specialize"
/** The following flags may be set by this phase: */
override def phaseNewFlags: Long = notPRIVATE | lateFINAL
/** This phase changes base classes. */
override def changesBaseClasses = true
override def keepsTypeParams = true
type TypeEnv = immutable.Map[Symbol, Type]
def emptyEnv: TypeEnv = Map[Symbol, Type]()
private implicit val typeOrdering: Ordering[Type] = Ordering[String] on ("" + _.typeSymbol.name)
import definitions.{
BooleanClass, UnitClass, ArrayClass,
ScalaValueClasses, isPrimitiveValueClass, isPrimitiveValueType,
SpecializedClass, UnspecializedClass, AnyRefClass, ObjectClass,
GroupOfSpecializable, uncheckedVarianceClass, ScalaInlineClass
}
import rootMirror.RootClass
/** TODO - this is a lot of maps.
*/
/** For a given class and concrete type arguments, give its specialized class */
val specializedClass: mutable.Map[(Symbol, TypeEnv), Symbol] = new mutable.LinkedHashMap
/** Map a method symbol to a list of its specialized overloads in the same class. */
private val overloads = perRunCaches.newMap[Symbol, List[Overload]]() withDefaultValue Nil
/** Map a symbol to additional information on specialization. */
private val info = perRunCaches.newMap[Symbol, SpecializedInfo]()
/** Map class symbols to the type environments where they were created. */
private val typeEnv = perRunCaches.newMap[Symbol, TypeEnv]() withDefaultValue emptyEnv
// Key: a specialized class or method
// Value: a map from tparams in the original class to tparams in the specialized class.
private val anyrefSpecCache = perRunCaches.newMap[Symbol, mutable.Map[Symbol, Symbol]]()
// holds mappings from members to the type variables in the class
// that they were already specialized for, so that they don't get
// specialized twice (this is for AnyRef specializations)
private val wasSpecializedForTypeVars = perRunCaches.newMap[Symbol, Set[Symbol]]() withDefaultValue Set()
/** Concrete methods that use a specialized type, or override such methods. */
private val concreteSpecMethods = perRunCaches.newWeakSet[Symbol]()
private def specializedTypes(tps: List[Symbol]) = tps filter (_.isSpecialized)
private def specializedOn(sym: Symbol): List[Symbol] = {
sym getAnnotation SpecializedClass match {
case Some(AnnotationInfo(_, Nil, _)) => specializableTypes.map(_.typeSymbol)
case Some(ann @ AnnotationInfo(_, args, _)) => {
args map (_.tpe) flatMap { tp =>
tp baseType GroupOfSpecializable match {
case TypeRef(_, GroupOfSpecializable, arg :: Nil) =>
arg.typeArgs map (_.typeSymbol)
case _ =>
tp.typeSymbol :: Nil
}
}
}
case _ => Nil
}
}
// If we replace `isBoundedGeneric` with (tp <:< AnyRefClass.tpe),
// then pos/spec-List.scala fails - why? Does this kind of check fail
// for similar reasons? Does `sym.isAbstractType` make a difference?
private def isSpecializedAnyRefSubtype(tp: Type, sym: Symbol) = {
specializedOn(sym).exists(s => !isPrimitiveValueClass(s)) &&
!isPrimitiveValueClass(tp.typeSymbol) &&
isBoundedGeneric(tp)
//(tp <:< AnyRefClass.tpe)
}
object TypeEnv {
/** Return a new type environment binding specialized type parameters of sym to
* the given args. Expects the lists to have the same length.
*/
def fromSpecialization(sym: Symbol, args: List[Type]): TypeEnv = {
ifDebug(assert(sym.info.typeParams.length == args.length, sym + " args: " + args))
emptyEnv ++ collectMap2(sym.info.typeParams, args)((k, v) => k.isSpecialized)
}
/** Does typeenv `t1` include `t2`? All type variables in `t1`
* are defined in `t2` and:
* - are bound to the same type, or
* - are an AnyRef specialization and `t2` is bound to a subtype of AnyRef
*/
def includes(t1: TypeEnv, t2: TypeEnv) = t1 forall {
case (sym, tpe) =>
t2 get sym exists { t2tp =>
(tpe == t2tp) || !(isPrimitiveValueType(tpe) || isPrimitiveValueType(t2tp)) // u.t.b. (t2tp <:< AnyRefClass.tpe)
}
}
/** Reduce the given environment to contain mappings only for type variables in tps. */
def restrict(env: TypeEnv, tps: immutable.Set[Symbol]): TypeEnv =
env filterKeys tps toMap
/** Is the given environment a valid specialization for sym?
* It is valid if each binding is from a @specialized type parameter in sym (or its owner)
* to a type for which `sym` is specialized.
*/
def isValid(env: TypeEnv, sym: Symbol): Boolean = {
env forall { case (tvar, tpe) =>
tvar.isSpecialized && (concreteTypes(tvar) contains tpe) && {
(sym.typeParams contains tvar) ||
(sym.owner != RootClass && (sym.owner.typeParams contains tvar))
}
}
}
}
/** Returns the generic class that was specialized to 'sClass', or
* 'sClass' itself if sClass is not a specialized subclass.
*/
def genericClass(sClass: Symbol): Symbol =
if (sClass.isSpecialized) sClass.superClass
else sClass
case class Overload(sym: Symbol, env: TypeEnv) {
override def toString = "specialized overload " + sym + " in " + env
}
/** Just to mark uncheckable */
override def newPhase(prev: scala.tools.nsc.Phase): StdPhase = new SpecializationPhase(prev)
class SpecializationPhase(prev: scala.tools.nsc.Phase) extends super.Phase(prev) {
override def checkable = false
}
protected def newTransformer(unit: CompilationUnit): Transformer =
new SpecializationTransformer(unit)
abstract class SpecializedInfo {
def target: Symbol
/** Are type bounds of @specialized type parameters of 'target' now in 'env'? */
def typeBoundsIn(env: TypeEnv) = false
/** A degenerated method has @specialized type parameters that appear only in
* type bounds of other @specialized type parameters (and not in its result type).
*/
def degenerate = false
def isAccessor = false
}
/** Symbol is a special overloaded method of 'original', in the environment env. */
case class SpecialOverload(original: Symbol, env: TypeEnv) extends SpecializedInfo {
def target = original
}
/** Symbol is a method that should be forwarded to 't' */
case class Forward(t: Symbol) extends SpecializedInfo {
def target = t
}
/** Symbol is a specialized abstract method, either specialized or original. The original `t` is abstract. */
case class Abstract(t: Symbol) extends SpecializedInfo {
def target = t
}
/** Symbol is a specialized accessor for the `target` field. */
case class SpecializedAccessor(target: Symbol) extends SpecializedInfo {
override def isAccessor = true
}
/** Symbol is a specialized method whose body should be the target's method body. */
case class Implementation(target: Symbol) extends SpecializedInfo
/** Symbol is a specialized override paired with `target`. */
case class SpecialOverride(target: Symbol) extends SpecializedInfo
/** A specialized inner class that specializes original inner class `target` on a type parameter of the enclosing class, in the typeenv `env`. */
case class SpecializedInnerClass(target: Symbol, env: TypeEnv) extends SpecializedInfo
/** Symbol is a normalized member obtained by specializing 'target'. */
case class NormalizedMember(target: Symbol) extends SpecializedInfo {
/** Type bounds of a @specialized type var are now in the environment. */
override def typeBoundsIn(env: TypeEnv): Boolean = {
target.info.typeParams exists { tvar =>
tvar.isSpecialized && (specializedTypeVars(tvar.info.bounds) exists env.isDefinedAt)
}
}
override lazy val degenerate = {
val stvTypeParams = specializedTypeVars(target.info.typeParams map (_.info))
val stvResult = specializedTypeVars(target.info.resultType)
debuglog("degenerate: " + target + " stv tparams: " + stvTypeParams + " stv info: " + stvResult)
(stvTypeParams -- stvResult).nonEmpty
}
}
/** Has `clazz` any type parameters that need be specialized? */
def hasSpecializedParams(clazz: Symbol) =
clazz.info.typeParams exists (_.isSpecialized)
/** Return specialized type parameters. */
def specializedParams(sym: Symbol): List[Symbol] =
sym.info.typeParams filter (_.isSpecialized)
def splitParams(tps: List[Symbol]) =
tps partition (_.isSpecialized)
/** Given an original class symbol and a list of types its type parameters are instantiated at
* returns a list of type parameters that should remain in the TypeRef when instantiating a
* specialized type.
*/
def survivingArgs(sym: Symbol, args: List[Type]): List[Type] =
for ((tvar, tpe) <- sym.info.typeParams.zip(args) if !tvar.isSpecialized || !isPrimitiveValueType(tpe))
yield tpe
val specializedType = new TypeMap {
override def apply(tp: Type): Type = tp match {
case TypeRef(pre, sym, args) if args.nonEmpty =>
val pre1 = this(pre)
// when searching for a specialized class, take care to map all
// type parameters that are subtypes of AnyRef to AnyRef
val args1 = map2(args, sym.info.typeParams)((tp, orig) =>
if (isSpecializedAnyRefSubtype(tp, orig)) AnyRefClass.tpe
else tp
)
specializedClass.get((sym, TypeEnv.fromSpecialization(sym, args1))) match {
case Some(sym1) => typeRef(pre1, sym1, survivingArgs(sym, args))
case None => typeRef(pre1, sym, args)
}
case _ => tp
}
}
/** Return the specialized overload of sym in the given env, if any. */
def overload(sym: Symbol, env: TypeEnv) =
overloads(sym).find(ov => TypeEnv.includes(ov.env, env))
/** Return the specialized name of 'sym' in the given environment. It
* guarantees the same result regardless of the map order by sorting
* type variables alphabetically.
*/
private def specializedName(sym: Symbol, env: TypeEnv): TermName = {
val tvars = (
if (sym.isClass) env.keySet
else specializedTypeVars(sym).intersect(env.keySet)
)
val (methparams, others) = tvars.toList sortBy ("" + _.name) partition (_.owner.isMethod)
// debuglog("specName(" + sym + ") env: " + env + " tvars: " + tvars)
specializedName(sym.name, methparams map env, others map env)
}
/** Specialize name for the two list of types. The first one denotes
* specialization on method type parameters, the second on outer environment.
*/
private def specializedName(name: Name, types1: List[Type], types2: List[Type]): TermName = {
if (nme.INITIALIZER == name || (types1.isEmpty && types2.isEmpty))
name
else if (nme.isSetterName(name))
nme.getterToSetter(specializedName(nme.setterToGetter(name), types1, types2))
else if (nme.isLocalName(name))
nme.getterToLocal(specializedName(nme.localToGetter(name), types1, types2))
else {
val (base, cs, ms) = nme.splitSpecializedName(name)
newTermName(base.toString + "$"
+ "m" + ms + types1.map(t => definitions.abbrvTag(t.typeSymbol)).mkString("", "", "")
+ "c" + cs + types2.map(t => definitions.abbrvTag(t.typeSymbol)).mkString("", "", "$sp"))
}
}
lazy val specializableTypes = ScalaValueClasses map (_.tpe) sorted
/** If the symbol is the companion of a value class, the value class.
* Otherwise, AnyRef.
*/
def specializesClass(sym: Symbol): Symbol = {
val c = sym.companionClass
if (isPrimitiveValueClass(c)) c else AnyRefClass
}
/** Return the types `sym` should be specialized at. This may be some of the primitive types
* or AnyRef. AnyRef means that a new type parameter T will be generated later, known to be a
* subtype of AnyRef (T <: AnyRef).
* These are in a meaningful order for stability purposes.
*/
def concreteTypes(sym: Symbol): List[Type] = {
val types = if (!sym.isSpecialized)
Nil // no @specialized Annotation
else
specializedOn(sym) map (s => specializesClass(s).tpe) sorted
if (isBoundedGeneric(sym.tpe) && (types contains AnyRefClass))
reporter.warning(sym.pos, sym + " is always a subtype of " + AnyRefClass.tpe + ".")
types
}
/** Return a list of all type environments for all specializations
* of @specialized types in `tps`.
*/
private def specializations(tps: List[Symbol]): List[TypeEnv] = {
// the keys in each TypeEnv
val keys: List[Symbol] = tps filter (_.isSpecialized)
// creating each permutation of concrete types
def loop(ctypes: List[List[Type]]): List[List[Type]] = ctypes match {
case Nil => Nil
case set :: Nil => set map (_ :: Nil)
case set :: sets => for (x <- set ; xs <- loop(sets)) yield x :: xs
}
// zip the keys with each permutation to create a TypeEnv.
// If we don't exclude the "all AnyRef" specialization, we will
// incur duplicate members and crash during mixin.
loop(keys map concreteTypes) filterNot (_ forall (_ <:< AnyRefClass.tpe)) map (xss => Map(keys zip xss: _*))
}
/** Does the given 'sym' need to be specialized in the environment 'env'?
* Specialization is needed for
* - members with specialized type parameters found in the given environment
* - constructors of specialized classes
* - normalized members whose type bounds appear in the environment
* But suppressed for:
* - any member with the @unspecialized annotation, or which has an
* enclosing member with the annotation.
*/
private def needsSpecialization(env: TypeEnv, sym: Symbol): Boolean = (
!sym.ownerChain.exists(_ hasAnnotation UnspecializedClass) && (
specializedTypeVars(sym).intersect(env.keySet).diff(wasSpecializedForTypeVars(sym)).nonEmpty
|| sym.isClassConstructor && (sym.enclClass.typeParams exists (_.isSpecialized))
|| isNormalizedMember(sym) && info(sym).typeBoundsIn(env)
)
)
def isNormalizedMember(m: Symbol) = m.isSpecialized && (info get m exists {
case NormalizedMember(_) => true
case _ => false
})
def specializedTypeVars(tpes: List[Type]): immutable.Set[Symbol] = {
val buf = Set.newBuilder[Symbol]
tpes foreach (tp => buf ++= specializedTypeVars(tp))
buf.result
}
def specializedTypeVars(sym: Symbol): immutable.Set[Symbol] = beforeTyper(specializedTypeVars(sym.info))
/** Return the set of @specialized type variables mentioned by the given type.
* It only counts type variables that appear:
* - naked
* - as arguments to type constructors in @specialized positions
* (arrays are considered as Array[@specialized T])
*/
def specializedTypeVars(tpe: Type): immutable.Set[Symbol] = tpe match {
case TypeRef(pre, sym, args) =>
if (sym.isAliasType)
specializedTypeVars(tpe.normalize)
else if (sym.isTypeParameter && sym.isSpecialized || (sym.isTypeSkolem && sym.deSkolemize.isSpecialized))
Set(sym)
else if (sym == ArrayClass)
specializedTypeVars(args)
else if (args.isEmpty)
Set()
else
specializedTypeVars(sym.typeParams zip args collect { case (tp, arg) if tp.isSpecialized => arg })
case PolyType(tparams, resTpe) => specializedTypeVars(resTpe :: tparams.map(_.info))
// since this method may be run at phase typer (before uncurry, where NMTs are eliminated)
case NullaryMethodType(resTpe) => specializedTypeVars(resTpe)
case MethodType(argSyms, resTpe) => specializedTypeVars(resTpe :: argSyms.map(_.tpe))
case ExistentialType(_, res) => specializedTypeVars(res)
case AnnotatedType(_, tp, _) => specializedTypeVars(tp)
case TypeBounds(lo, hi) => specializedTypeVars(lo :: hi :: Nil)
case RefinedType(parents, _) => parents flatMap specializedTypeVars toSet
case _ => Set()
}
/** Returns the type parameter in the specialized class `sClass` that corresponds to type parameter
* `tparam` in the original class. It will create it if needed or use the one from the cache.
*/
private def typeParamSubAnyRef(tparam: Symbol, sClass: Symbol): Type = {
val sClassMap = anyrefSpecCache.getOrElseUpdate(sClass, mutable.Map[Symbol, Symbol]())
sClassMap.getOrElseUpdate(tparam,
tparam.cloneSymbol(sClass, tparam.flags, tparam.name append tpnme.SPECIALIZED_SUFFIX)
modifyInfo (info => TypeBounds(info.bounds.lo, AnyRefClass.tpe))
).tpe
}
/** Cleans the anyrefSpecCache of all type parameter symbols of a class.
*/
private def cleanAnyRefSpecCache(clazz: Symbol, decls: List[Symbol]) {
// remove class type parameters and those of normalized members.
clazz :: decls foreach (anyrefSpecCache remove _)
}
/** Type parameters that survive when specializing in the specified environment. */
def survivingParams(params: List[Symbol], env: TypeEnv) =
params filter {
p =>
!p.isSpecialized ||
!env.contains(p) ||
!isPrimitiveValueType(env(p))
}
/** Produces the symbols from type parameters `syms` of the original owner,
* in the given type environment `env`. The new owner is `nowner`.
*
* Non-specialized type parameters are cloned into new ones.
* Type parameters specialized on AnyRef have preexisting symbols.
*
* For instance, a @specialized(AnyRef) T, will become T$sp <: AnyRef.
*/
def produceTypeParameters(syms: List[Symbol], nowner: Symbol, env: TypeEnv) = {
val cloned = for (s <- syms) yield if (!env.contains(s)) s.cloneSymbol(nowner) else env(s).typeSymbol
// log("producing type params: " + cloned.map(t => (t, t.tpe.bounds.hi)))
foreach2(syms, cloned) { (orig, cln) =>
cln.removeAnnotation(SpecializedClass)
if (env.contains(orig))
cln modifyInfo (info => TypeBounds(info.bounds.lo, AnyRefClass.tpe))
}
cloned map (_ substInfo (syms, cloned))
}
/** Maps AnyRef bindings from a raw environment (holding AnyRefs) into type parameters from
* the specialized symbol (class (specialization) or member (normalization)), leaves everything else as-is.
*/
private def mapAnyRefsInSpecSym(env: TypeEnv, origsym: Symbol, specsym: Symbol): TypeEnv = env map {
case (sym, tp) if tp == AnyRefClass.tpe && sym.owner == origsym => (sym, typeParamSubAnyRef(sym, specsym))
case x => x
}
/** Maps AnyRef bindings from a raw environment (holding AnyRefs) into type parameters from
* the original class, leaves everything else as-is.
*/
private def mapAnyRefsInOrigCls(env: TypeEnv, origcls: Symbol): TypeEnv = env map {
case (sym, tp) if (tp == AnyRefClass.tpe) && sym.owner == origcls => (sym, sym.tpe)
case x => x
}
/** Specialize 'clazz', in the environment `outerEnv`. The outer
* environment contains bindings for specialized types of enclosing
* classes.
*
* A class C is specialized w.r.t to its own specialized type params
* `stps`, by specializing its members, and creating a new class for
* each combination of `stps`.
*/
def specializeClass(clazz: Symbol, outerEnv: TypeEnv): List[Symbol] = {
def specializedClass(env0: TypeEnv, normMembers: List[Symbol]): Symbol = {
/** It gets hard to follow all the clazz and cls, and specializedClass
* was both already used for a map and mucho long. So "sClass" is the
* specialized subclass of "clazz" throughout this file.
*/
// SI-5545: Eliminate classes with the same name loaded from the bytecode already present - all we need to do is
// to force .info on them, as their lazy type will be evaluated and the symbols will be eliminated. Unfortunately
// evaluating the info after creating the specialized class will mess the specialized class signature, so we'd
// better evaluate it before creating the new class symbol
val clazzName = specializedName(clazz, env0).toTypeName
val bytecodeClazz = clazz.owner.info.decl(clazzName)
// debuglog("Specializing " + clazz + ", but found " + bytecodeClazz + " already there")
bytecodeClazz.info
val sClass = clazz.owner.newClass(clazzName, clazz.pos, (clazz.flags | SPECIALIZED) & ~CASE)
def cloneInSpecializedClass(member: Symbol, flagFn: Long => Long, newName: Name = null) =
member.cloneSymbol(sClass, flagFn(member.flags | SPECIALIZED), newName)
sClass.sourceFile = clazz.sourceFile
currentRun.symSource(sClass) = clazz.sourceFile // needed later on by mixin
val env = mapAnyRefsInSpecSym(env0, clazz, sClass)
typeEnv(sClass) = env
this.specializedClass((clazz, env0)) = sClass
val decls1 = newScope // declarations of the newly specialized class 'sClass'
var oldClassTParams: List[Symbol] = Nil // original unspecialized type parameters
var newClassTParams: List[Symbol] = Nil // unspecialized type parameters of 'specializedClass' (cloned)
// has to be a val in order to be computed early. It is later called
// within 'atPhase(next)', which would lead to an infinite cycle otherwise
val specializedInfoType: Type = {
oldClassTParams = survivingParams(clazz.info.typeParams, env)
newClassTParams = produceTypeParameters(oldClassTParams, sClass, env) map subst(env)
// log("new tparams " + newClassTParams.zip(newClassTParams map {s => (s.tpe, s.tpe.bounds.hi)}) + ", in env: " + env)
def applyContext(tpe: Type) =
subst(env, tpe).instantiateTypeParams(oldClassTParams, newClassTParams map (_.tpe))
/** Return a list of specialized parents to be re-mixed in a specialized subclass.
* Assuming env = [T -> Int] and
* class Integral[@specialized T] extends Numeric[T]
* and Numeric[U] is specialized on U, this produces List(Numeric$mcI).
*
* so that class Integral$mci extends Integral[Int] with Numeric$mcI.
*/
def specializedParents(parents: List[Type]): List[Type] = {
var res: List[Type] = Nil
// log(specializedClass + ": seeking specialized parents of class with parents: " + parents.map(_.typeSymbol))
for (p <- parents) {
val stp = afterSpecialize(specializedType(p))
if (stp != p)
if (p.typeSymbol.isTrait) res ::= stp
else if (currentRun.compiles(clazz))
reporter.warning(clazz.pos, p.typeSymbol + " must be a trait. Specialized version of "
+ clazz + " will inherit generic " + p) // TODO change to error
}
res
}
var parents = List(applyContext(beforeTyper(clazz.tpe)))
// log("!!! Parents: " + parents + ", sym: " + parents.map(_.typeSymbol))
if (parents.head.typeSymbol.isTrait)
parents = parents.head.parents.head :: parents
val extraSpecializedMixins = specializedParents(clazz.info.parents map applyContext)
if (extraSpecializedMixins.nonEmpty)
debuglog("extra specialized mixins for %s: %s".format(clazz.name.decode, extraSpecializedMixins.mkString(", ")))
// If the class being specialized has a self-type, the self type may
// require specialization. First exclude classes whose self types have
// the same type constructor as the class itself, since they will
// already be covered. Then apply the current context to the self-type
// as with the parents and assign it to typeOfThis.
if (clazz.typeOfThis.typeConstructor ne clazz.typeConstructor) {
sClass.typeOfThis = applyContext(clazz.typeOfThis)
debuglog("Rewriting self-type for specialized class:\n" +
" " + clazz.defStringSeenAs(clazz.typeOfThis) + "\n" +
" => " + sClass.defStringSeenAs(sClass.typeOfThis)
)
}
GenPolyType(newClassTParams, ClassInfoType(parents ::: extraSpecializedMixins, decls1, sClass))
}
afterSpecialize(sClass setInfo specializedInfoType)
val fullEnv = outerEnv ++ env
/** Enter 'sym' in the scope of the current specialized class. It's type is
* mapped through the active environment, binding type variables to concrete
* types. The existing typeEnv for `sym` is composed with the current active
* environment
*/
def enterMember(sym: Symbol): Symbol = {
typeEnv(sym) = fullEnv ++ typeEnv(sym) // append the full environment
sym modifyInfo (_.substThis(clazz, sClass).instantiateTypeParams(oldClassTParams, newClassTParams map (_.tpe)))
// we remove any default parameters. At this point, they have been all
// resolved by the type checker. Later on, erasure re-typechecks everything and
// chokes if it finds default parameters for specialized members, even though
// they are never needed.
mapParamss(sym)(_ resetFlag DEFAULTPARAM)
decls1 enter subst(fullEnv)(sym)
}
/** Create and enter in scope an overridden symbol m1 for `m` that forwards
* to `om`. `om` is a fresh, special overload of m1 that is an implementation
* of `m`. For example, for a
*
* class Foo[@specialized A] {
* def m(x: A) = <body> // m
* }
* , for class Foo$I extends Foo[Int], this method enters two new symbols in
* the scope of Foo$I:
*
* def m(x: Int) = m$I(x) // m1
* def m$I(x: Int) = <body>/adapted to env {A -> Int} // om
*/
def forwardToOverload(m: Symbol): Symbol = {
val specMember = enterMember(cloneInSpecializedClass(m, f => (f | OVERRIDE) & ~(DEFERRED | CASEACCESSOR)))
val om = specializedOverload(sClass, m, env).setFlag(OVERRIDE)
val original = info.get(m) match {
case Some(NormalizedMember(tg)) => tg
case _ => m
}
info(specMember) = Forward(om)
info(om) = if (original.isDeferred) Forward(original) else Implementation(original)
typeEnv(om) = env ++ typeEnv(m) // add the environment for any method tparams
overloads(specMember) ::= Overload(om, typeEnv(om))
enterMember(om)
}
for (m <- normMembers ; if needsSpecialization(outerEnv ++ env, m) && satisfiable(fullEnv)) {
if (!m.isDeferred)
addConcreteSpecMethod(m)
// specialized members have to be overridable.
if (m.isPrivate)
m.resetFlag(PRIVATE).setFlag(PROTECTED)
if (m.isConstructor) {
val specCtor = enterMember(cloneInSpecializedClass(m, x => x))
info(specCtor) = Forward(m)
}
else if (isNormalizedMember(m)) { // methods added by normalization
val NormalizedMember(original) = info(m)
if (nonConflicting(env ++ typeEnv(m))) {
if (info(m).degenerate) {
debuglog("degenerate normalized member " + m.defString)
val specMember = enterMember(cloneInSpecializedClass(m, _ & ~DEFERRED))
info(specMember) = Implementation(original)
typeEnv(specMember) = env ++ typeEnv(m)
} else {
val om = forwardToOverload(m)
debuglog("normalizedMember " + m + " om: " + om + " " + pp(typeEnv(om)))
}
}
else
debuglog("conflicting env for " + m + " env: " + env)
}
else if (m.isDeferred) { // abstract methods
val specMember = enterMember(cloneInSpecializedClass(m, _ | DEFERRED))
// debuglog("deferred " + specMember.fullName + " remains abstract")
info(specMember) = new Abstract(specMember)
// was: new Forward(specMember) {
// override def target = m.owner.info.member(specializedName(m, env))
// }
} else if (m.isMethod && !m.hasAccessorFlag) { // other concrete methods
// log("other concrete " + m)
forwardToOverload(m)
} else if (m.isMethod && m.hasFlag(LAZY)) {
forwardToOverload(m)
} else if (m.isValue && !m.isMethod && !m.hasFlag(LAZY)) { // concrete value definition
def mkAccessor(field: Symbol, name: Name) = {
val newFlags = (SPECIALIZED | m.getter(clazz).flags) & ~(LOCAL | CASEACCESSOR | PARAMACCESSOR)
// we rely on the super class to initialize param accessors
val sym = sClass.newMethod(name, field.pos, newFlags)
info(sym) = SpecializedAccessor(field)
sym
}
def overrideIn(clazz: Symbol, sym: Symbol) = {
val newFlags = (sym.flags | OVERRIDE | SPECIALIZED) & ~(DEFERRED | CASEACCESSOR | PARAMACCESSOR)
val sym1 = sym.cloneSymbol(clazz, newFlags)
sym1 modifyInfo (_ asSeenFrom (clazz.tpe, sym1.owner))
}
val specVal = specializedOverload(sClass, m, env)
addConcreteSpecMethod(m)
specVal.asInstanceOf[TermSymbol].setAlias(m)
enterMember(specVal)
// create accessors
// debuglog("m: " + m + " isLocal: " + nme.isLocalName(m.name) + " specVal: " + specVal.name + " isLocal: " + nme.isLocalName(specVal.name))
if (nme.isLocalName(m.name)) {
val specGetter = mkAccessor(specVal, nme.localToGetter(specVal.name)) setInfo MethodType(Nil, specVal.info)
val origGetter = overrideIn(sClass, m.getter(clazz))
info(origGetter) = Forward(specGetter)
enterMember(specGetter)
enterMember(origGetter)
debuglog("specialize accessor in %s: %s -> %s".format(sClass.name.decode, origGetter.name.decode, specGetter.name.decode))
clazz.caseFieldAccessors.find(_.name.startsWith(m.name)) foreach { cfa =>
val cfaGetter = overrideIn(sClass, cfa)
info(cfaGetter) = SpecializedAccessor(specVal)
enterMember(cfaGetter)
debuglog("override case field accessor %s -> %s".format(m.name.decode, cfaGetter.name.decode))
}
if (specVal.isVariable && m.setter(clazz) != NoSymbol) {
val specSetter = mkAccessor(specVal, nme.getterToSetter(specGetter.name))
.resetFlag(STABLE)
specSetter.setInfo(MethodType(specSetter.newSyntheticValueParams(List(specVal.info)),
UnitClass.tpe))
val origSetter = overrideIn(sClass, m.setter(clazz))
info(origSetter) = Forward(specSetter)
enterMember(specSetter)
enterMember(origSetter)
}
}
else { // if there are no accessors, specialized methods will need to access this field in specialized subclasses
m.resetFlag(PRIVATE)
specVal.resetFlag(PRIVATE)
debuglog("no accessors for %s/%s, specialized methods must access field in subclass".format(
m.name.decode, specVal.name.decode))
}
}
else if (m.isClass) {
val specClass: Symbol = cloneInSpecializedClass(m, x => x)
typeEnv(specClass) = fullEnv
specClass setName specializedName(specClass, fullEnv).toTypeName
enterMember(specClass)
debuglog("entered specialized class " + specClass.fullName)
info(specClass) = SpecializedInnerClass(m, fullEnv)
}
}
sClass
}
val decls1 = clazz.info.decls.toList flatMap { m: Symbol =>
if (m.isAnonymousClass) List(m) else {
normalizeMember(m.owner, m, outerEnv) flatMap { normalizedMember =>
val ms = specializeMember(m.owner, normalizedMember, outerEnv, clazz.info.typeParams)
// interface traits have concrete members now
if (ms.nonEmpty && clazz.isTrait && clazz.isInterface)
clazz.resetFlag(INTERFACE)
if (normalizedMember.isMethod) {
val newTpe = subst(outerEnv, normalizedMember.info)
// only do it when necessary, otherwise the method type might be at a later phase already
if (newTpe != normalizedMember.info) {
normalizedMember updateInfo newTpe
}
}
normalizedMember :: ms
}
}
}
val subclasses = specializations(clazz.info.typeParams) filter satisfiable
subclasses foreach {
env =>
val spc = specializedClass(env, decls1)
val existing = clazz.owner.info.decl(spc.name)
// a symbol for the specialized class already exists if there's a classfile for it.
// keeping both crashes the compiler on test/files/pos/spec-Function1.scala
if (existing != NoSymbol)
clazz.owner.info.decls.unlink(existing)
afterSpecialize(clazz.owner.info.decls enter spc) //!!! assumes fully specialized classes
}
if (subclasses.nonEmpty) clazz.resetFlag(FINAL)
cleanAnyRefSpecCache(clazz, decls1)
decls1
}
/** Expand member `sym` to a set of normalized members. Normalized members
* are monomorphic or polymorphic only in non-specialized types.
*
* Given method m[@specialized T, U](x: T, y: U) it returns
* m[T, U](x: T, y: U),
* m$I[ U](x: Int, y: U),
* m$D[ U](x: Double, y: U)
* // etc.
*/
private def normalizeMember(owner: Symbol, sym: Symbol, outerEnv: TypeEnv): List[Symbol] = {
sym :: (
if (!sym.isMethod || beforeTyper(sym.typeParams.isEmpty)) Nil
else {
// debuglog("normalizeMember: " + sym.fullNameAsName('.').decode)
var specializingOn = specializedParams(sym)
val unusedStvars = specializingOn filterNot specializedTypeVars(sym.info)
// I think the last condition should be !sym.isArtifact, but that made the
// compiler start warning about Tuple1.scala and Tuple2.scala claiming
// their type parameters are used in non-specializable positions. Why is
// unusedStvars.nonEmpty for these classes???
if (unusedStvars.nonEmpty && currentRun.compiles(sym) && !sym.isSynthetic) {
reporter.warning(sym.pos,
"%s %s unused or used in non-specializable positions.".format(
unusedStvars.mkString("", ", ", ""),
if (unusedStvars.length == 1) "is" else "are")
)
unusedStvars foreach (_ removeAnnotation SpecializedClass)
specializingOn = specializingOn filterNot (unusedStvars contains)
}
for (env0 <- specializations(specializingOn) if needsSpecialization(env0, sym)) yield {
// !!! Can't this logic be structured so that the new symbol's name is
// known when the symbol is cloned? It is much cleaner not to be mutating
// names after the fact. And it adds about a billion lines of
// "Renaming value _1 in class Tuple2 to _1$mcZ$sp" to obscure the small
// number of other (important) actual symbol renamings.
val tps = survivingParams(sym.info.typeParams, env0)
val specMember = sym.cloneSymbol(owner, (sym.flags | SPECIALIZED) & ~DEFERRED) // <-- this needs newName = ...
val env = mapAnyRefsInSpecSym(env0, sym, specMember)
val (keys, vals) = env.toList.unzip
specMember setName specializedName(sym, env) // <-- but the name is calculated based on the cloned symbol
// debuglog("%s normalizes to %s%s".format(sym, specMember,
// if (tps.isEmpty) "" else " with params " + tps.mkString(", ")))
typeEnv(specMember) = outerEnv ++ env
val tps1 = produceTypeParameters(tps, specMember, env)
tps1 foreach (_ modifyInfo (_.instantiateTypeParams(keys, vals)))
// the cloneInfo is necessary so that method parameter symbols are cloned at the new owner
val methodType = sym.info.resultType.instantiateTypeParams(keys ++ tps, vals ++ tps1.map(_.tpe)).cloneInfo(specMember)
specMember setInfo GenPolyType(tps1, methodType)
debuglog("%s expands to %s in %s".format(sym, specMember.name.decode, pp(env)))
info(specMember) = NormalizedMember(sym)
overloads(sym) ::= Overload(specMember, env)
owner.info.decls.enter(specMember)
specMember
}
}
)
}
// concise printing of type env
private def pp(env: TypeEnv): String = {
env.toList.sortBy(_._1.name) map {
case (k, v) =>
val vsym = v.typeSymbol
if (k == vsym) "" + k.name
else k.name + ":" + vsym.name
} mkString ("env(", ", ", ")")
}
/** Specialize member `m` w.r.t. to the outer environment and the type
* parameters of the innermost enclosing class.
*
* Turns 'private' into 'protected' for members that need specialization.
*
* Return a list of symbols that are specializations of 'sym', owned by 'owner'.
*/
private def specializeMember(owner: Symbol, sym: Symbol, outerEnv: TypeEnv, tps: List[Symbol]): List[Symbol] = {
def specializeOn(tparams: List[Symbol]): List[Symbol] = specializations(tparams) map { spec0 =>
val spec = mapAnyRefsInOrigCls(spec0, owner)
if (sym.isPrivate) {
sym.resetFlag(PRIVATE).setFlag(PROTECTED)
debuglog("Set %s to private[%s]".format(sym, sym.enclosingPackage))
}
val specMember = subst(outerEnv)(specializedOverload(owner, sym, spec))
typeEnv(specMember) = typeEnv(sym) ++ outerEnv ++ spec
wasSpecializedForTypeVars(specMember) ++= spec collect { case (s, tp) if s.tpe == tp => s }
val wasSpec = wasSpecializedForTypeVars(specMember)
if (wasSpec.nonEmpty)
debuglog("specialized overload for %s in %s".format(specMember, pp(typeEnv(specMember))))
overloads(sym) ::= Overload(specMember, spec)
info(specMember) = SpecialOverload(sym, typeEnv(specMember))
specMember
}
if (sym.isMethod) {
val stvars = specializedTypeVars(sym)
if (stvars.nonEmpty)
debuglog("specialized %s on %s".format(sym.fullLocationString, stvars.map(_.name).mkString(", ")))
val tps1 = if (sym.isConstructor) tps filter (sym.info.paramTypes contains _) else tps
val tps2 = tps1 filter stvars
if (!sym.isDeferred)
addConcreteSpecMethod(sym)
specializeOn(tps2)
}
else Nil
}
/** Return the specialized overload of `m`, in the given environment. */
private def specializedOverload(owner: Symbol, sym: Symbol, env: TypeEnv): Symbol = {
val newFlags = (sym.flags | SPECIALIZED) & ~(DEFERRED | CASEACCESSOR)
// this method properly duplicates the symbol's info
( sym.cloneSymbol(owner, newFlags, newName = specializedName(sym, env))
modifyInfo (info => subst(env, info.asSeenFrom(owner.thisType, sym.owner)))
)
}
/** For each method m that overrides an inherited method m', add a special
* overload method `om` that overrides the corresponding overload in the
* superclass. For the following example:
*
* class IntFun extends Function1[Int, Int] {
* def apply(x: Int): Int = ..
* }
*
* this method will return List('apply$mcII$sp')
*/
private def specialOverrides(clazz: Symbol) = logResultIf[List[Symbol]]("specialized overrides in " + clazz, _.nonEmpty) {
/** Return the overridden symbol in syms that needs a specialized overriding symbol,
* together with its specialization environment. The overridden symbol may not be
* the closest to 'overriding', in a given hierarchy.
*
* An method m needs a special override if
* * m overrides a method whose type contains specialized type variables
* * there is a valid specialization environment that maps the overridden method type to m's type.
*/
def needsSpecialOverride(overriding: Symbol): (Symbol, TypeEnv) = {
def checkOverriddenTParams(overridden: Symbol) {
foreach2(overridden.info.typeParams, overriding.info.typeParams) { (baseTvar, derivedTvar) =>
val missing = concreteTypes(baseTvar).toSet -- concreteTypes(derivedTvar).toSet
if (missing.nonEmpty) {
reporter.error(derivedTvar.pos,
"Type parameter has to be specialized at least for the same types as in the overridden method. Missing "
+ "types: " + missing.mkString("", ", ", "")
)
}
}
}
if (!overriding.isParamAccessor) {
for (overridden <- overriding.allOverriddenSymbols) {
val stvars = specializedTypeVars(overridden.info)
if (stvars.nonEmpty) {
debuglog("specialized override of %s by %s%s".format(overridden.fullLocationString, overriding.fullLocationString,
if (stvars.isEmpty) "" else stvars.map(_.name).mkString("(", ", ", ")")))
if (currentRun compiles overriding)
checkOverriddenTParams(overridden)
val env = unify(overridden.info, overriding.info, emptyEnv, false, true)
def atNext = afterSpecialize(overridden.owner.info.decl(specializedName(overridden, env)))
if (TypeEnv.restrict(env, stvars).nonEmpty && TypeEnv.isValid(env, overridden) && atNext != NoSymbol) {
debuglog(" " + pp(env) + " found " + atNext)
return (overridden, env)
}
}
}
}
(NoSymbol, emptyEnv)
}
(clazz.info.decls flatMap { overriding =>
needsSpecialOverride(overriding) match {
case (NoSymbol, _) => None
case (overridden, env) =>
val om = specializedOverload(clazz, overridden, env)
debuglog("specialized overload %s for %s in %s: %s".format(om, overriding.name.decode, pp(env), om.info))
typeEnv(om) = env
addConcreteSpecMethod(overriding)
info(om) = (
if (overriding.isDeferred) { // abstract override
debuglog("abstract override " + overriding.fullName + " with specialized " + om.fullName)
Forward(overriding)
}
else {
// if the override is a normalized member, 'om' gets the
// implementation from its original target, and adds the
// environment of the normalized member (that is, any
// specialized /method/ type parameter bindings)
val impl = info get overriding match {
case Some(NormalizedMember(target)) =>
typeEnv(om) = env ++ typeEnv(overriding)
target
case _ =>
overriding
}
info(overriding) = Forward(om setPos overriding.pos)
SpecialOverride(impl)
}
)
overloads(overriding) ::= Overload(om, env)
ifDebug(afterSpecialize(assert(
overridden.owner.info.decl(om.name) != NoSymbol,
"Could not find " + om.name + " in " + overridden.owner.info.decls))
)
Some(om)
}
}).toList
}
case object UnifyError extends scala.util.control.ControlThrowable
private[this] def unifyError(tp1: Any, tp2: Any): Nothing = {
log("unifyError" + ((tp1, tp2)))
throw UnifyError
}
/** Return the most general type environment that specializes tp1 to tp2.
* It only allows binding of type parameters annotated with @specialized.
* Fails if such an environment cannot be found.
*
* If `strict` is true, a UnifyError is thrown if unification is impossible.
*
* If `tparams` is true, then the methods tries to unify over type params in polytypes as well.
*/
private def unify(tp1: Type, tp2: Type, env: TypeEnv, strict: Boolean, tparams: Boolean = false): TypeEnv = (tp1, tp2) match {
case (TypeRef(_, sym1, _), _) if sym1.isSpecialized =>
debuglog("Unify " + tp1 + ", " + tp2)
if (isPrimitiveValueClass(tp2.typeSymbol) || isSpecializedAnyRefSubtype(tp2, sym1))
env + ((sym1, tp2))
else if (isSpecializedAnyRefSubtype(tp2, sym1))
env + ((sym1, tp2)) // env + ((sym1, AnyRefClass.tpe))
else if (strict)
unifyError(tp1, tp2)
else
env
case (TypeRef(_, sym1, args1), TypeRef(_, sym2, args2)) =>
if (args1.nonEmpty || args2.nonEmpty)
debuglog("Unify types " + tp1 + " and " + tp2)
if (strict && args1.length != args2.length) unifyError(tp1, tp2)
val e = unify(args1, args2, env, strict)
if (e.nonEmpty) debuglog("unified to: " + e)
e
case (TypeRef(_, sym1, _), _) if sym1.isTypeParameterOrSkolem =>
env
case (MethodType(params1, res1), MethodType(params2, res2)) =>
if (strict && params1.length != params2.length) unifyError(tp1, tp2)
debuglog("Unify methods " + tp1 + " and " + tp2)
unify(res1 :: (params1 map (_.tpe)), res2 :: (params2 map (_.tpe)), env, strict)
case (PolyType(tparams1, res1), PolyType(tparams2, res2)) =>
debuglog("Unify polytypes " + tp1 + " and " + tp2)
if (strict && tparams1.length != tparams2.length)
unifyError(tp1, tp2)
else if (tparams && tparams1.length == tparams2.length)
unify(res1 :: tparams1.map(_.info), res2 :: tparams2.map(_.info), env, strict)
else
unify(res1, res2, env, strict)
case (PolyType(_, res), other) => unify(res, other, env, strict)
case (ThisType(_), ThisType(_)) => env
case (_, SingleType(_, _)) => unify(tp1, tp2.underlying, env, strict)
case (SingleType(_, _), _) => unify(tp1.underlying, tp2, env, strict)
case (ThisType(_), _) => unify(tp1.widen, tp2, env, strict)
case (_, ThisType(_)) => unify(tp1, tp2.widen, env, strict)
case (RefinedType(_, _), RefinedType(_, _)) => env
case (AnnotatedType(_, tp1, _), tp2) => unify(tp2, tp1, env, strict)
case (ExistentialType(_, res1), _) => unify(tp2, res1, env, strict)
case (TypeBounds(lo1, hi1), TypeBounds(lo2, hi2)) => unify(List(lo1, hi1), List(lo2, hi2), env, strict)
case _ =>
debuglog("don't know how to unify %s [%s] with %s [%s]".format(tp1, tp1.getClass, tp2, tp2.getClass))
env
}
private def unify(tp1: List[Type], tp2: List[Type], env: TypeEnv, strict: Boolean): TypeEnv = {
if (tp1.isEmpty || tp2.isEmpty) env
else (tp1 zip tp2).foldLeft(env) { (env, args) =>
if (!strict) unify(args._1, args._2, env, strict)
else {
val nenv = unify(args._1, args._2, emptyEnv, strict)
if (env.keySet intersect nenv.keySet isEmpty) env ++ nenv
else {
debuglog("could not unify: u(" + args._1 + ", " + args._2 + ") yields " + nenv + ", env: " + env)
unifyError(tp1, tp2)
}
}
}
}
/** Apply type bindings in the given environment `env` to all declarations. */
private def subst(env: TypeEnv, decls: List[Symbol]): List[Symbol] =
decls map subst(env)
/** Apply the type environment 'env' to the given type. All type
* bindings are supposed to be to primitive types. A type variable
* that is annotated with 'uncheckedVariance' is mapped to the corresponding
* primitive type losing the annotation.
*/
private def subst(env: TypeEnv, tpe: Type): Type = {
class FullTypeMap(from: List[Symbol], to: List[Type]) extends SubstTypeMap(from, to) with AnnotationFilter {
def keepAnnotation(annot: AnnotationInfo) = !(annot matches uncheckedVarianceClass)
override def mapOver(tp: Type): Type = tp match {
case ClassInfoType(parents, decls, clazz) =>
val parents1 = parents mapConserve this
val decls1 = mapOver(decls)
if ((parents1 eq parents) && (decls1 eq decls)) tp
else ClassInfoType(parents1, decls1, clazz)
case _ =>
super.mapOver(tp)
}
}
val (keys, values) = env.toList.unzip
(new FullTypeMap(keys, values))(tpe)
}
private def subst(env: TypeEnv)(decl: Symbol): Symbol =
decl modifyInfo (info =>
if (decl.isConstructor) MethodType(subst(env, info).params, decl.owner.tpe)
else subst(env, info)
)
/** Checks if the type parameter symbol is not specialized
* and is used as type parameters when extending a class with a specialized
* type parameter.
* At some point we may remove this restriction.
*
* Example:
*
* class Base[@specialized T]
* class Derived[T] extends Base[T] // a non-specialized T is
* // used as a type param for Base
* // -> returning true
*/
private def notSpecializedIn(tsym: Symbol, supertpe: Type) = supertpe match {
case TypeRef(_, supersym, supertargs) =>
val tspec = specializedOn(tsym).toSet
for (supt <- supersym.typeParams) {
val supspec = specializedOn(supt).toSet
if (tspec != supspec && tspec.subsetOf(supspec))
reporter.error(tsym.pos, "Type parameter has to be specialized at least for the same types as in the superclass. Missing types: " + (supspec.diff(tspec)).mkString(", "))
}
case _ => //log("nope")
}
private def unspecializableClass(tp: Type) = (
definitions.isRepeatedParamType(tp) // ???
|| tp.typeSymbol.isJavaDefined
|| tp.typeSymbol.isPackageClass
)
/** Type transformation. It is applied to all symbols, compiled or loaded.
* If it is a 'no-specialization' run, it is applied only to loaded symbols.
*/
override def transformInfo(sym: Symbol, tpe: Type): Type = {
if (settings.nospecialization.value && currentRun.compiles(sym)) tpe
else tpe.resultType match {
case cinfo @ ClassInfoType(parents, decls, clazz) if !unspecializableClass(cinfo) =>
val tparams = tpe.typeParams
if (tparams.isEmpty)
afterSpecialize(parents map (_.typeSymbol.info))
val parents1 = parents mapConserve specializedType
if (parents ne parents1) {
debuglog("specialization transforms %s%s parents to %s".format(
if (tparams.nonEmpty) "(poly) " else "", clazz, parents1)
)
}
val newScope = newScopeWith(specializeClass(clazz, typeEnv(clazz)) ++ specialOverrides(clazz): _*)
// If tparams.isEmpty, this is just the ClassInfoType.
GenPolyType(tparams, ClassInfoType(parents1, newScope, clazz))
case _ =>
tpe
}
}
/** Is any type variable in `env` conflicting with any if its type bounds, when
* type bindings in `env` are taken into account?
*
* A conflicting type environment could still be satisfiable.
*/
def conflicting(env: TypeEnv) = !nonConflicting(env)
def nonConflicting(env: TypeEnv) = env forall { case (tvar, tpe) =>
(subst(env, tvar.info.bounds.lo) <:< tpe) && (tpe <:< subst(env, tvar.info.bounds.hi))
}
/** The type environment is sound w.r.t. to all type bounds or only soft
* conflicts appear. An environment is sound if all bindings are within
* the bounds of the given type variable. A soft conflict is a binding
* that does not fall within the bounds, but whose bounds contain
* type variables that are @specialized, (that could become satisfiable).
*/
def satisfiable(env: TypeEnv): Boolean = satisfiable(env, false)
def satisfiable(env: TypeEnv, warnings: Boolean): Boolean = {
def matches(tpe1: Type, tpe2: Type): Boolean = {
val t1 = subst(env, tpe1)
val t2 = subst(env, tpe2)
((t1 <:< t2)
|| specializedTypeVars(t1).nonEmpty
|| specializedTypeVars(t2).nonEmpty)
}
env forall { case (tvar, tpe) =>
matches(tvar.info.bounds.lo, tpe) && matches(tpe, tvar.info.bounds.hi) || {
if (warnings)
reporter.warning(tvar.pos, "Bounds prevent specialization of " + tvar)
debuglog("specvars: " +
tvar.info.bounds.lo + ": " +
specializedTypeVars(tvar.info.bounds.lo) + " " +
subst(env, tvar.info.bounds.hi) + ": " +
specializedTypeVars(subst(env, tvar.info.bounds.hi))
)
false
}
}
}
def satisfiabilityConstraints(env: TypeEnv): Option[TypeEnv] = {
val noconstraints = Some(emptyEnv)
def matches(tpe1: Type, tpe2: Type): Option[TypeEnv] = {
val t1 = subst(env, tpe1)
val t2 = subst(env, tpe2)
// log("---------> " + tpe1 + " matches " + tpe2)
// log(t1 + ", " + specializedTypeVars(t1))
// log(t2 + ", " + specializedTypeVars(t2))
// log("unify: " + unify(t1, t2, env, false, false) + " in " + env)
if (t1 <:< t2) noconstraints
else if (specializedTypeVars(t1).nonEmpty) Some(unify(t1, t2, env, false, false) -- env.keys)
else if (specializedTypeVars(t2).nonEmpty) Some(unify(t2, t1, env, false, false) -- env.keys)
else None
}
env.foldLeft[Option[TypeEnv]](noconstraints) {
case (constraints, (tvar, tpe)) =>
val loconstraints = matches(tvar.info.bounds.lo, tpe)
val hiconstraints = matches(tpe, tvar.info.bounds.hi)
val allconstraints = for (c <- constraints; l <- loconstraints; h <- hiconstraints) yield c ++ l ++ h
allconstraints
}
}
/** This duplicator additionally performs casts of expressions if that is allowed by the `casts` map. */
class Duplicator(casts: Map[Symbol, Type]) extends {
val global: SpecializeTypes.this.global.type = SpecializeTypes.this.global
} with typechecker.Duplicators {
private val (castfrom, castto) = casts.unzip
private object CastMap extends SubstTypeMap(castfrom.toList, castto.toList)
class BodyDuplicator(_context: Context) extends super.BodyDuplicator(_context) {
override def castType(tree: Tree, pt: Type): Tree = {
// log(" expected type: " + pt)
// log(" tree type: " + tree.tpe)
tree.tpe = if (tree.tpe != null) fixType(tree.tpe) else null
// log(" tree type: " + tree.tpe)
val ntree = if (tree.tpe != null && !(tree.tpe <:< pt)) {
val casttpe = CastMap(tree.tpe)
if (casttpe <:< pt) gen.mkCast(tree, casttpe)
else if (casttpe <:< CastMap(pt)) gen.mkCast(tree, pt)
else tree
} else tree
ntree.tpe = null
ntree
}
}
protected override def newBodyDuplicator(context: Context) = new BodyDuplicator(context)
}
/** A tree symbol substituter that substitutes on type skolems.
* If a type parameter is a skolem, it looks for the original
* symbol in the 'from' and maps it to the corresponding new
* symbol. The new symbol should probably be a type skolem as
* well (not enforced).
*
* All private members are made protected in order to be accessible from
* specialized classes.
*/
class ImplementationAdapter(from: List[Symbol],
to: List[Symbol],
targetClass: Symbol,
addressFields: Boolean) extends TreeSymSubstituter(from, to) {
override val symSubst = new SubstSymMap(from, to) {
override def matches(sym1: Symbol, sym2: Symbol) =
if (sym2.isTypeSkolem) sym2.deSkolemize eq sym1
else sym1 eq sym2
}
private def isAccessible(sym: Symbol): Boolean =
(currentClass == sym.owner.enclClass) && (currentClass != targetClass)
private def shouldMakePublic(sym: Symbol): Boolean =
sym.hasFlag(PRIVATE | PROTECTED) && (addressFields || !nme.isLocalName(sym.name))
/** All private members that are referenced are made protected,
* in order to be accessible from specialized subclasses.
*/
override def transform(tree: Tree): Tree = tree match {
case Select(qual, name) =>
val sym = tree.symbol
if (sym.isPrivate) debuglog(
"seeing private member %s, currentClass: %s, owner: %s, isAccessible: %b, isLocalName: %b".format(
sym, currentClass, sym.owner.enclClass, isAccessible(sym), nme.isLocalName(sym.name))
)
if (shouldMakePublic(sym) && !isAccessible(sym)) {
debuglog("changing private flag of " + sym)
sym.makeNotPrivate(sym.owner)
}
super.transform(tree)
case _ =>
super.transform(tree)
}
}
/** Return the generic class corresponding to this specialized class. */
def originalClass(clazz: Symbol): Symbol =
if (clazz.isSpecialized) {
val (originalName, _, _) = nme.splitSpecializedName(clazz.name)
clazz.owner.info.decl(originalName).suchThat(_.isClass)
} else NoSymbol
def illegalSpecializedInheritance(clazz: Symbol): Boolean = (
clazz.isSpecialized
&& originalClass(clazz).parentSymbols.exists(p => hasSpecializedParams(p) && !p.isTrait)
)
def specializeCalls(unit: CompilationUnit) = new TypingTransformer(unit) {
/** Map a specializable method to it's rhs, when not deferred. */
val body = perRunCaches.newMap[Symbol, Tree]()
/** Map a specializable method to its value parameter symbols. */
val parameters = perRunCaches.newMap[Symbol, List[Symbol]]()
/** Collect method bodies that are concrete specialized methods.
*/
class CollectMethodBodies extends Traverser {
override def traverse(tree: Tree) = tree match {
case DefDef(_, _, _, vparams :: Nil, _, rhs) =>
if (concreteSpecMethods(tree.symbol) || tree.symbol.isConstructor) {
// debuglog("!!! adding body of a defdef %s, symbol %s: %s".format(tree, tree.symbol, rhs))
body(tree.symbol) = rhs
// body(tree.symbol) = tree // whole method
parameters(tree.symbol) = vparams.map(_.symbol)
concreteSpecMethods -= tree.symbol
} // no need to descend further down inside method bodies
case ValDef(mods, name, tpt, rhs) if concreteSpecMethods(tree.symbol) =>
body(tree.symbol) = rhs
// log("!!! adding body of a valdef " + tree.symbol + ": " + rhs)
//super.traverse(tree)
case _ =>
super.traverse(tree)
}
}
def doesConform(origSymbol: Symbol, treeType: Type, memberType: Type, env: TypeEnv) = {
(treeType =:= memberType) || { // anyref specialization
memberType match {
case PolyType(_, resTpe) =>
debuglog("Conformance for anyref - polytype with result type: " + resTpe + " and " + treeType + "\nOrig. sym.: " + origSymbol)
try {
val e = unify(origSymbol.tpe, memberType, emptyEnv, true)
debuglog("obtained env: " + e)
e.keySet == env.keySet
} catch {
case _ =>
debuglog("Could not unify.")
false
}
case _ => false
}
}
}
def reportError[T](body: =>T)(handler: TypeError => T): T =
try body
catch {
case te: TypeError =>
reporter.error(te.pos, te.msg)
handler(te)
}
override def transform(tree: Tree): Tree =
reportError { transform1(tree) } {_ => tree}
def transform1(tree: Tree) = {
val symbol = tree.symbol
/** The specialized symbol of 'tree.symbol' for tree.tpe, if there is one */
def specSym(qual: Tree): Option[Symbol] = {
val env = unify(symbol.tpe, tree.tpe, emptyEnv, false)
debuglog("[specSym] checking for rerouting: %s with \n\tsym.tpe: %s, \n\ttree.tpe: %s \n\tenv: %s \n\tname: %s"
.format(tree, symbol.tpe, tree.tpe, env, specializedName(symbol, env)))
if (!env.isEmpty) { // a method?
val specCandidates = qual.tpe.member(specializedName(symbol, env))
val specMember = specCandidates suchThat { s =>
doesConform(symbol, tree.tpe, qual.tpe.memberType(s), env)
}
debuglog("[specSym] found: " + specCandidates.tpe + ", instantiated as: " + tree.tpe)
debuglog("[specSym] found specMember: " + specMember)
if (specMember ne NoSymbol)
if (TypeEnv.includes(typeEnv(specMember), env)) Some(specMember)
else {
debuglog("wrong environments for specialized member: \n\ttypeEnv(%s) = %s\n\tenv = %s".format(specMember, typeEnv(specMember), env))
None
}
else None
} else None
}
curTree = tree
tree match {
case Apply(Select(New(tpt), nme.CONSTRUCTOR), args) =>
def transformNew = {
debuglog("Attempting to specialize new %s(%s)".format(tpt, args.mkString(", ")))
val found = findSpec(tpt.tpe)
if (found.typeSymbol ne tpt.tpe.typeSymbol) {
// the ctor can be specialized
debuglog("** instantiated specialized type: " + found)
reportError {
localTyper.typedPos(tree.pos)(New(found, transformTrees(args): _*))
} {
_ => super.transform(tree)
}
} else super.transform(tree)
}
transformNew
case Apply(sel @ Select(sup @ Super(qual, name), name1), args)
if (sup.symbol.info.parents != beforePrevPhase(sup.symbol.info.parents)) =>
def transformSuperApply = {
def parents = sup.symbol.info.parents
debuglog(tree + " parents changed from: " + beforePrevPhase(parents) + " to: " + parents)
val res = localTyper.typed(
Apply(Select(Super(qual, name) setPos sup.pos, name1) setPos sel.pos, transformTrees(args)) setPos tree.pos)
debuglog("retyping call to super, from: " + symbol + " to " + res.symbol)
res
}
transformSuperApply
case TypeApply(sel @ Select(qual, name), targs)
if (!specializedTypeVars(symbol.info).isEmpty && name != nme.CONSTRUCTOR) =>
def transformTypeApply = {
debuglog("checking typeapp for rerouting: " + tree + " with sym.tpe: " + symbol.tpe + " tree.tpe: " + tree.tpe)
val qual1 = transform(qual)
// log(">>> TypeApply: " + tree + ", qual1: " + qual1)
specSym(qual1) match {
case Some(specMember) =>
debuglog("found " + specMember.fullName)
ifDebug(assert(symbol.info.typeParams.length == targs.length, symbol.info.typeParams + " / " + targs))
val env = typeEnv(specMember)
val residualTargs = symbol.info.typeParams zip targs collect {
case (tvar, targ) if !env.contains(tvar) || !isPrimitiveValueClass(env(tvar).typeSymbol) => targ
}
// See SI-5583. Don't know why it happens now if it didn't before.
if (specMember.info.typeParams.isEmpty && residualTargs.nonEmpty) {
log("!!! Type args to be applied, but symbol says no parameters: " + ((specMember.defString, residualTargs)))
localTyper.typed(sel)
}
else {
ifDebug(assert(residualTargs.length == specMember.info.typeParams.length,
"residual: %s, tparams: %s, env: %s".format(residualTargs, specMember.info.typeParams, env))
)
val tree1 = gen.mkTypeApply(Select(qual1, specMember), residualTargs)
debuglog("rewrote " + tree + " to " + tree1)
localTyper.typedOperator(atPos(tree.pos)(tree1)) // being polymorphic, it must be a method
}
case None =>
treeCopy.TypeApply(tree, treeCopy.Select(sel, qual1, name), super.transformTrees(targs))
// See pos/exponential-spec.scala - can't call transform on the whole tree again.
// super.transform(tree)
}
}
transformTypeApply
case Select(qual, name) =>
def transformSelect = {
qual match {
case _: Super if illegalSpecializedInheritance(currentClass) =>
val pos = tree.pos
debuglog(pos.source.file.name+":"+pos.line+": not specializing call to super inside illegal specialized inheritance class.")
debuglog(pos.lineContent)
tree
case _ =>
debuglog("specializing Select %s [tree.tpe: %s]".format(symbol.defString, tree.tpe))
//log("!!! select " + tree + " -> " + symbol.info + " specTypeVars: " + specializedTypeVars(symbol.info))
if (specializedTypeVars(symbol.info).nonEmpty && name != nme.CONSTRUCTOR) {
// log("!!! unifying " + (symbol, symbol.tpe) + " and " + (tree, tree.tpe))
val env = unify(symbol.tpe, tree.tpe, emptyEnv, false)
// log("!!! found env: " + env + "; overloads: " + overloads(symbol))
if (!env.isEmpty) {
// debuglog("checking for rerouting: " + tree + " with sym.tpe: " + symbol.tpe + " tree.tpe: " + tree.tpe + " env: " + env)
val specMember = overload(symbol, env)
if (specMember.isDefined) {
localTyper.typedOperator(atPos(tree.pos)(Select(transform(qual), specMember.get.sym.name)))
}
else {
val qual1 = transform(qual)
val specMember = qual1.tpe.member(specializedName(symbol, env)).suchThat(_.tpe matches subst(env, symbol.tpe))
if (specMember ne NoSymbol) {
val tree1 = atPos(tree.pos)(Select(qual1, specMember))
if (specMember.isMethod)
localTyper.typedOperator(tree1)
else
localTyper.typed(tree1)
} else
treeCopy.Select(tree, qual1, name)
}
} else
super.transform(tree)
} else overloads(symbol).find(_.sym.info =:= symbol.info) match {
case Some(specMember) =>
val qual1 = transform(qual)
debuglog("** routing " + tree + " to " + specMember.sym.fullName + " tree: " + Select(qual1, specMember.sym))
localTyper.typedOperator(atPos(tree.pos)(Select(qual1, specMember.sym)))
case None =>
super.transform(tree)
}
}
}
transformSelect
case PackageDef(pid, stats) =>
tree.symbol.info // make sure specializations have been performed
atOwner(tree, symbol) {
val specMembers = implSpecClasses(stats) map localTyper.typed
treeCopy.PackageDef(tree, pid, transformStats(stats ::: specMembers, symbol.moduleClass))
}
case Template(parents, self, body) =>
def transformTemplate = {
val specMembers = makeSpecializedMembers(tree.symbol.enclClass) ::: (implSpecClasses(body) map localTyper.typed)
if (!symbol.isPackageClass)
(new CollectMethodBodies)(tree)
val parents1 = map2(currentOwner.info.parents, parents)((tpe, parent) =>
TypeTree(tpe) setPos parent.pos)
treeCopy.Template(tree,
parents1 /*currentOwner.info.parents.map(tpe => TypeTree(tpe) setPos parents.head.pos)*/ ,
self,
atOwner(currentOwner)(transformTrees(body ::: specMembers)))
}
transformTemplate
case ddef @ DefDef(_, _, _, vparamss, _, _) if info.isDefinedAt(symbol) =>
def transformDefDef = {
// log("--> method: " + ddef + " in " + ddef.symbol.owner + ", " + info(symbol))
def reportTypeError(body: =>Tree) = reportError(body)(_ => ddef)
if (symbol.isConstructor) {
val t = atOwner(symbol)(forwardCtorCall(tree.pos, gen.mkSuperSelect, vparamss, symbol.owner))
if (symbol.isPrimaryConstructor)
localTyper.typedPos(symbol.pos)(deriveDefDef(tree)(_ => Block(List(t), Literal(Constant()))))
else // duplicate the original constructor
reportTypeError(duplicateBody(ddef, info(symbol).target))
}
else info(symbol) match {
case Implementation(target) =>
assert(body.isDefinedAt(target), "sym: " + symbol.fullName + " target: " + target.fullName)
// we have an rhs, specialize it
val tree1 = reportTypeError {
duplicateBody(ddef, target)
}
debuglog("implementation: " + tree1)
deriveDefDef(tree1)(transform)
case NormalizedMember(target) =>
val constraints = satisfiabilityConstraints(typeEnv(symbol))
log("constraints: " + constraints)
if (target.isDeferred || constraints == None) {
deriveDefDef(tree)(_ => localTyper typed gen.mkSysErrorCall("Fatal error in code generation: this should never be called."))
} else {
// we have an rhs, specialize it
val tree1 = reportTypeError {
duplicateBody(ddef, target, constraints.get)
}
debuglog("implementation: " + tree1)
deriveDefDef(tree1)(transform)
}
case SpecialOverride(target) =>
assert(body.isDefinedAt(target), "sym: " + symbol.fullName + " target: " + target.fullName)
//debuglog("moving implementation, body of target " + target + ": " + body(target))
debuglog("%s is param accessor? %b".format(ddef.symbol, ddef.symbol.isParamAccessor))
// we have an rhs, specialize it
val tree1 = addBody(ddef, target)
(new ChangeOwnerTraverser(target, tree1.symbol))(tree1.rhs)
debuglog("changed owners, now: " + tree1)
deriveDefDef(tree1)(transform)
case SpecialOverload(original, env) =>
debuglog("completing specialized " + symbol.fullName + " calling " + original)
debuglog("special overload " + original + " -> " + env)
val t = DefDef(symbol, { vparamss =>
val fun = Apply(Select(This(symbol.owner), original),
makeArguments(original, vparamss.head))
debuglog("inside defdef: " + symbol + "; type: " + symbol.tpe + "; owner: " + symbol.owner)
gen.maybeMkAsInstanceOf(fun,
symbol.owner.thisType.memberType(symbol).finalResultType,
symbol.owner.thisType.memberType(original).finalResultType)
})
debuglog("created special overload tree " + t)
debuglog("created " + t)
reportError {
localTyper.typed(t)
} {
_ => super.transform(tree)
}
case fwd @ Forward(_) =>
debuglog("forward: " + fwd + ", " + ddef)
val rhs1 = forwardCall(tree.pos, gen.mkAttributedRef(symbol.owner.thisType, fwd.target), vparamss)
debuglog("-->d completed forwarder to specialized overload: " + fwd.target + ": " + rhs1)
reportError {
localTyper.typed(deriveDefDef(tree)(_ => rhs1))
} {
_ => super.transform(tree)
}
case SpecializedAccessor(target) =>
val rhs1 = if (symbol.isGetter)
gen.mkAttributedRef(target)
else
Assign(gen.mkAttributedRef(target), Ident(vparamss.head.head.symbol))
debuglog("specialized accessor: " + target + " -> " + rhs1)
localTyper.typed(deriveDefDef(tree)(_ => rhs1))
case Abstract(targ) =>
debuglog("abstract: " + targ)
localTyper.typed(deriveDefDef(tree)(rhs => rhs))
}
}
transformDefDef
case ValDef(_, _, _, _) if symbol.hasFlag(SPECIALIZED) && !symbol.isParamAccessor =>
def transformValDef = {
assert(body.isDefinedAt(symbol.alias), body)
val tree1 = deriveValDef(tree)(_ => body(symbol.alias).duplicate)
debuglog("now typing: " + tree1 + " in " + tree.symbol.owner.fullName)
val d = new Duplicator(emptyEnv)
val newValDef = d.retyped(
localTyper.context1.asInstanceOf[d.Context],
tree1,
symbol.alias.enclClass,
symbol.enclClass,
typeEnv(symbol.alias) ++ typeEnv(tree.symbol)
)
deriveValDef(newValDef)(transform)
}
transformValDef
case _ =>
super.transform(tree)
}
}
/** Duplicate the body of the given method `tree` to the new symbol `source`.
*
* Knowing that the method can be invoked only in the `castmap` type environment,
* this method will insert casts for all the expressions of types mappend in the
* `castmap`.
*/
private def duplicateBody(tree: DefDef, source: Symbol, castmap: TypeEnv = emptyEnv) = {
val symbol = tree.symbol
val meth = addBody(tree, source)
val d = new Duplicator(castmap)
debuglog("-->d DUPLICATING: " + meth)
d.retyped(
localTyper.context1.asInstanceOf[d.Context],
meth,
source.enclClass,
symbol.enclClass,
typeEnv(source) ++ typeEnv(symbol)
)
}
/** Put the body of 'source' as the right hand side of the method 'tree'.
* The destination method gets fresh symbols for type and value parameters,
* and the body is updated to the new symbols, and owners adjusted accordingly.
* However, if the same source tree is used in more than one place, full re-typing
* is necessary. @see method duplicateBody
*/
private def addBody(tree: DefDef, source: Symbol): DefDef = {
val symbol = tree.symbol
debuglog("specializing body of" + symbol.defString)
val DefDef(_, _, tparams, vparams :: Nil, tpt, _) = tree
// val (_, origtparams) = splitParams(source.typeParams)
val env = typeEnv(symbol)
val boundTvars = env.keySet
val origtparams = source.typeParams.filter(tparam => !boundTvars(tparam) || !isPrimitiveValueType(env(tparam)))
if (origtparams.nonEmpty || symbol.typeParams.nonEmpty)
debuglog("substituting " + origtparams + " for " + symbol.typeParams)
// skolemize type parameters
val oldtparams = tparams map (_.symbol)
val newtparams = deriveFreshSkolems(oldtparams)
map2(tparams, newtparams)(_ setSymbol _)
// create fresh symbols for value parameters to hold the skolem types
val newSyms = cloneSymbolsAtOwnerAndModify(vparams map (_.symbol), symbol, _.substSym(oldtparams, newtparams))
// replace value and type parameters of the old method with the new ones
// log("Adding body for " + tree.symbol + " - origtparams: " + origtparams + "; tparams: " + tparams)
// log("Type vars of: " + source + ": " + source.typeParams)
// log("Type env of: " + tree.symbol + ": " + boundTvars)
// log("newtparams: " + newtparams)
val symSubstituter = new ImplementationAdapter(
parameters(source) ::: origtparams,
newSyms ::: newtparams,
source.enclClass,
false) // don't make private fields public
val newBody = symSubstituter(body(source).duplicate)
tpt.tpe = tpt.tpe.substSym(oldtparams, newtparams)
copyDefDef(tree)(vparamss = List(newSyms map ValDef), rhs = newBody)
}
/** Create trees for specialized members of 'sClass', based on the
* symbols that are already there.
*/
private def makeSpecializedMembers(sClass: Symbol): List[Tree] = {
// add special overrides first
// if (!specializedClass.hasFlag(SPECIALIZED))
// for (m <- specialOverrides(specializedClass)) specializedClass.info.decls.enter(m)
val mbrs = new mutable.ListBuffer[Tree]
var hasSpecializedFields = false
for (m <- sClass.info.decls
if m.hasFlag(SPECIALIZED)
&& (m.sourceFile ne null)
&& satisfiable(typeEnv(m), !sClass.hasFlag(SPECIALIZED))) {
debuglog("creating tree for " + m.fullName)
if (m.isMethod) {
if (info(m).target.hasAccessorFlag) hasSpecializedFields = true
if (m.isClassConstructor) {
val origParams = parameters(info(m).target)
val vparams = (
map2(m.info.paramTypes, origParams)((tp, sym) =>
m.newValue(specializedName(sym, typeEnv(sClass)), sym.pos, sym.flags) setInfo tp
)
)
// param accessors for private members (the others are inherited from the generic class)
if (m.isPrimaryConstructor) {
for (param <- vparams ; if sClass.info.nonPrivateMember(param.name) == NoSymbol) {
val acc = param.cloneSymbol(sClass, param.flags | PARAMACCESSOR | PRIVATE)
sClass.info.decls.enter(acc)
mbrs += ValDef(acc, EmptyTree).setType(NoType).setPos(m.pos)
}
}
// ctor
mbrs += atPos(m.pos)(DefDef(m, Modifiers(m.flags), mmap(List(vparams))(ValDef), EmptyTree))
} else {
mbrs += atPos(m.pos)(DefDef(m, { paramss => EmptyTree }))
}
} else if (m.isValue) {
mbrs += ValDef(m, EmptyTree).setType(NoType).setPos(m.pos)
} else if (m.isClass) {
// mbrs +=
// ClassDef(m, Template(m.info.parents map TypeTree, emptyValDef, List())
// .setSymbol(m.newLocalDummy(m.pos)))
// log("created synthetic class: " + m.fullName)
}
}
if (hasSpecializedFields) {
val isSpecializedInstance = sClass :: sClass.parentSymbols exists (_ hasFlag SPECIALIZED)
val sym = sClass.newMethod(nme.SPECIALIZED_INSTANCE, sClass.pos) setInfoAndEnter MethodType(Nil, BooleanClass.tpe)
mbrs += atPos(sym.pos) {
DefDef(sym, Literal(Constant(isSpecializedInstance)).setType(BooleanClass.tpe)).setType(NoType)
}
}
mbrs.toList
}
/** Create specialized class definitions */
def implSpecClasses(trees: List[Tree]): List[Tree] = {
val buf = new mutable.ListBuffer[Tree]
for (tree <- trees)
tree match {
case ClassDef(_, _, _, impl) =>
tree.symbol.info // force specialization
for (((sym1, env), specCls) <- specializedClass if sym1 == tree.symbol) {
val parents = specCls.info.parents.map(TypeTree)
buf +=
ClassDef(specCls, atPos(impl.pos)(Template(parents, emptyValDef, List()))
.setSymbol(specCls.newLocalDummy(sym1.pos))) setPos tree.pos
debuglog("created synthetic class: " + specCls + " of " + sym1 + " in " + pp(env))
}
case _ =>
}
buf.toList
}
}
private def forwardCall(pos: scala.reflect.internal.util.Position, receiver: Tree, paramss: List[List[ValDef]]): Tree = {
val argss = mmap(paramss)(x => Ident(x.symbol))
atPos(pos) { (receiver /: argss) (Apply.apply) }
}
/** Forward to the generic class constructor. If the current class initializes
* specialized fields corresponding to parameters, it passes null to the superclass
* constructor. This saves the boxing cost for initializing generic fields that are
* never used.
*
* For example:
* {{{
* case class Tuple2[T, U](x: T, y: U)
*
* class Tuple2$II {
* val _x$I: Int = ..
* def x = _x$I
* // same for y
* def this(x: Int, y: Int) {
* super.this(null.asInstanceOf[Int], null.asInstanceOf[Int])
* }
* }
* }}
*/
private def forwardCtorCall(pos: scala.reflect.internal.util.Position, receiver: Tree, paramss: List[List[ValDef]], clazz: Symbol): Tree = {
/** A constructor parameter `f` initializes a specialized field
* iff:
* - it is specialized itself
* - there is a getter for the original (non-specialized) field in the same class
* - there is a getter for the specialized field in the same class
*/
def initializesSpecializedField(f: Symbol) = (
(f.name endsWith nme.SPECIALIZED_SUFFIX)
&& clazz.info.member(nme.originalName(f.name)).isPublic
&& clazz.info.decl(f.name).suchThat(_.isGetter) != NoSymbol
)
val argss = mmap(paramss)(x =>
if (initializesSpecializedField(x.symbol))
gen.mkAsInstanceOf(Literal(Constant(null)), x.symbol.tpe)
else
Ident(x.symbol)
)
atPos(pos) { (receiver /: argss) (Apply.apply) }
}
/** Add method m to the set of symbols for which we need an implementation tree
* in the tree transformer.
*
* @note This field is part of the specializeTypes subcomponent, so any symbols
* that here are not garbage collected at the end of a compiler run!
*/
def addConcreteSpecMethod(m: Symbol) {
if (currentRun.compiles(m)) concreteSpecMethods += m
}
private def makeArguments(fun: Symbol, vparams: List[Symbol]): List[Tree] = (
//! TODO: make sure the param types are seen from the right prefix
map2(fun.info.paramTypes, vparams)((tp, arg) => gen.maybeMkAsInstanceOf(Ident(arg), tp, arg.tpe))
)
private def findSpec(tp: Type): Type = tp match {
case TypeRef(pre, sym, _ :: _) => specializedType(tp)
case _ => tp
}
class SpecializationTransformer(unit: CompilationUnit) extends Transformer {
informProgress("specializing " + unit)
override def transform(tree: Tree) = {
val resultTree = if (settings.nospecialization.value) tree
else afterSpecialize(specializeCalls(unit).transform(tree))
// Remove the final modifier and @inline annotation from anything in the
// original class (since it's being overridden in at least onesubclass).
//
// We do this here so that the specialized subclasses will correctly copy
// final and @inline.
info.foreach {
case (sym, SpecialOverload(target, _)) => {
sym.resetFlag(FINAL)
target.resetFlag(FINAL)
sym.removeAnnotation(ScalaInlineClass)
target.removeAnnotation(ScalaInlineClass)
}
case _ => {}
}
resultTree
}
}
def printSpecStats() {
println(" concreteSpecMembers: %7d".format(concreteSpecMethods.size))
println(" overloads: %7d".format(overloads.size))
println(" typeEnv: %7d".format(typeEnv.size))
println(" info: %7d".format(info.size))
}
}
|