summaryrefslogtreecommitdiffstats
path: root/mfbt/Vector.h
blob: 07e370426492ec9b66cb432b7f86ca48c634ca02 (plain)
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
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/* A type/length-parametrized vector class. */

#ifndef mozilla_Vector_h
#define mozilla_Vector_h

#include "mozilla/Alignment.h"
#include "mozilla/AllocPolicy.h"
#include "mozilla/ArrayUtils.h" // for PointerRangeSize
#include "mozilla/Assertions.h"
#include "mozilla/Attributes.h"
#include "mozilla/MathAlgorithms.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/Move.h"
#include "mozilla/OperatorNewExtensions.h"
#include "mozilla/ReentrancyGuard.h"
#include "mozilla/TemplateLib.h"
#include "mozilla/TypeTraits.h"

#include <new> // for placement new

/* Silence dire "bugs in previous versions of MSVC have been fixed" warnings */
#ifdef _MSC_VER
#pragma warning(push)
#pragma warning(disable:4345)
#endif

namespace mozilla {

template<typename T, size_t N, class AllocPolicy>
class Vector;

namespace detail {

/*
 * Check that the given capacity wastes the minimal amount of space if
 * allocated on the heap. This means that aCapacity*sizeof(T) is as close to a
 * power-of-two as possible. growStorageBy() is responsible for ensuring this.
 */
template<typename T>
static bool CapacityHasExcessSpace(size_t aCapacity)
{
  size_t size = aCapacity * sizeof(T);
  return RoundUpPow2(size) - size >= sizeof(T);
}

/*
 * This template class provides a default implementation for vector operations
 * when the element type is not known to be a POD, as judged by IsPod.
 */
template<typename T, size_t N, class AP, bool IsPod>
struct VectorImpl
{
  /*
   * Constructs an object in the uninitialized memory at *aDst with aArgs.
   */
  template<typename... Args>
  MOZ_NONNULL(1)
  static inline void new_(T* aDst, Args&&... aArgs)
  {
    new(KnownNotNull, aDst) T(Forward<Args>(aArgs)...);
  }

  /* Destroys constructed objects in the range [aBegin, aEnd). */
  static inline void destroy(T* aBegin, T* aEnd)
  {
    MOZ_ASSERT(aBegin <= aEnd);
    for (T* p = aBegin; p < aEnd; ++p) {
      p->~T();
    }
  }

  /* Constructs objects in the uninitialized range [aBegin, aEnd). */
  static inline void initialize(T* aBegin, T* aEnd)
  {
    MOZ_ASSERT(aBegin <= aEnd);
    for (T* p = aBegin; p < aEnd; ++p) {
      new_(p);
    }
  }

  /*
   * Copy-constructs objects in the uninitialized range
   * [aDst, aDst+(aSrcEnd-aSrcStart)) from the range [aSrcStart, aSrcEnd).
   */
  template<typename U>
  static inline void copyConstruct(T* aDst,
                                   const U* aSrcStart, const U* aSrcEnd)
  {
    MOZ_ASSERT(aSrcStart <= aSrcEnd);
    for (const U* p = aSrcStart; p < aSrcEnd; ++p, ++aDst) {
      new_(aDst, *p);
    }
  }

  /*
   * Move-constructs objects in the uninitialized range
   * [aDst, aDst+(aSrcEnd-aSrcStart)) from the range [aSrcStart, aSrcEnd).
   */
  template<typename U>
  static inline void moveConstruct(T* aDst, U* aSrcStart, U* aSrcEnd)
  {
    MOZ_ASSERT(aSrcStart <= aSrcEnd);
    for (U* p = aSrcStart; p < aSrcEnd; ++p, ++aDst) {
      new_(aDst, Move(*p));
    }
  }

  /*
   * Copy-constructs objects in the uninitialized range [aDst, aDst+aN) from
   * the same object aU.
   */
  template<typename U>
  static inline void copyConstructN(T* aDst, size_t aN, const U& aU)
  {
    for (T* end = aDst + aN; aDst < end; ++aDst) {
      new_(aDst, aU);
    }
  }

  /*
   * Grows the given buffer to have capacity aNewCap, preserving the objects
   * constructed in the range [begin, end) and updating aV. Assumes that (1)
   * aNewCap has not overflowed, and (2) multiplying aNewCap by sizeof(T) will
   * not overflow.
   */
  static inline MOZ_MUST_USE bool
  growTo(Vector<T, N, AP>& aV, size_t aNewCap)
  {
    MOZ_ASSERT(!aV.usingInlineStorage());
    MOZ_ASSERT(!CapacityHasExcessSpace<T>(aNewCap));
    T* newbuf = aV.template pod_malloc<T>(aNewCap);
    if (MOZ_UNLIKELY(!newbuf)) {
      return false;
    }
    T* dst = newbuf;
    T* src = aV.beginNoCheck();
    for (; src < aV.endNoCheck(); ++dst, ++src) {
      new_(dst, Move(*src));
    }
    VectorImpl::destroy(aV.beginNoCheck(), aV.endNoCheck());
    aV.free_(aV.mBegin);
    aV.mBegin = newbuf;
    /* aV.mLength is unchanged. */
    aV.mCapacity = aNewCap;
    return true;
  }
};

/*
 * This partial template specialization provides a default implementation for
 * vector operations when the element type is known to be a POD, as judged by
 * IsPod.
 */
template<typename T, size_t N, class AP>
struct VectorImpl<T, N, AP, true>
{
  template<typename... Args>
  MOZ_NONNULL(1)
  static inline void new_(T* aDst, Args&&... aArgs)
  {
    // Explicitly construct a local object instead of using a temporary since
    // T(args...) will be treated like a C-style cast in the unary case and
    // allow unsafe conversions. Both forms should be equivalent to an
    // optimizing compiler.
    T temp(Forward<Args>(aArgs)...);
    *aDst = temp;
  }

  static inline void destroy(T*, T*) {}

  static inline void initialize(T* aBegin, T* aEnd)
  {
    /*
     * You would think that memset would be a big win (or even break even)
     * when we know T is a POD. But currently it's not. This is probably
     * because |append| tends to be given small ranges and memset requires
     * a function call that doesn't get inlined.
     *
     * memset(aBegin, 0, sizeof(T) * (aEnd - aBegin));
     */
    MOZ_ASSERT(aBegin <= aEnd);
    for (T* p = aBegin; p < aEnd; ++p) {
      new_(p);
    }
  }

  template<typename U>
  static inline void copyConstruct(T* aDst,
                                   const U* aSrcStart, const U* aSrcEnd)
  {
    /*
     * See above memset comment. Also, notice that copyConstruct is
     * currently templated (T != U), so memcpy won't work without
     * requiring T == U.
     *
     * memcpy(aDst, aSrcStart, sizeof(T) * (aSrcEnd - aSrcStart));
     */
    MOZ_ASSERT(aSrcStart <= aSrcEnd);
    for (const U* p = aSrcStart; p < aSrcEnd; ++p, ++aDst) {
      new_(aDst, *p);
    }
  }

  template<typename U>
  static inline void moveConstruct(T* aDst,
                                   const U* aSrcStart, const U* aSrcEnd)
  {
    copyConstruct(aDst, aSrcStart, aSrcEnd);
  }

  static inline void copyConstructN(T* aDst, size_t aN, const T& aT)
  {
    for (T* end = aDst + aN; aDst < end; ++aDst) {
      new_(aDst, aT);
    }
  }

  static inline MOZ_MUST_USE bool
  growTo(Vector<T, N, AP>& aV, size_t aNewCap)
  {
    MOZ_ASSERT(!aV.usingInlineStorage());
    MOZ_ASSERT(!CapacityHasExcessSpace<T>(aNewCap));
    T* newbuf = aV.template pod_realloc<T>(aV.mBegin, aV.mCapacity, aNewCap);
    if (MOZ_UNLIKELY(!newbuf)) {
      return false;
    }
    aV.mBegin = newbuf;
    /* aV.mLength is unchanged. */
    aV.mCapacity = aNewCap;
    return true;
  }

  static inline void
  podResizeToFit(Vector<T, N, AP>& aV)
  {
    if (aV.usingInlineStorage() || aV.mLength == aV.mCapacity) {
      return;
    }
    T* newbuf = aV.template pod_realloc<T>(aV.mBegin, aV.mCapacity, aV.mLength);
    if (MOZ_UNLIKELY(!newbuf)) {
      return;
    }
    aV.mBegin = newbuf;
    aV.mCapacity = aV.mLength;
  }
};

// A struct for TestVector.cpp to access private internal fields.
// DO NOT DEFINE IN YOUR OWN CODE.
struct VectorTesting;

} // namespace detail

/*
 * STL-like container providing a short-lived, dynamic buffer.  Vector calls the
 * constructors/destructors of all elements stored in its internal buffer, so
 * non-PODs may be safely used.  Additionally, Vector will store the first N
 * elements in-place before resorting to dynamic allocation.
 *
 * T requirements:
 *  - default and copy constructible, assignable, destructible
 *  - operations do not throw
 * MinInlineCapacity requirements:
 *  - any value, however, MinInlineCapacity is clamped to min/max values
 * AllocPolicy:
 *  - see "Allocation policies" in AllocPolicy.h (defaults to
 *    mozilla::MallocAllocPolicy)
 *
 * Vector is not reentrant: T member functions called during Vector member
 * functions must not call back into the same object!
 */
template<typename T,
         size_t MinInlineCapacity = 0,
         class AllocPolicy = MallocAllocPolicy>
class Vector final : private AllocPolicy
{
  /* utilities */

  static const bool kElemIsPod = IsPod<T>::value;
  typedef detail::VectorImpl<T, MinInlineCapacity, AllocPolicy, kElemIsPod> Impl;
  friend struct detail::VectorImpl<T, MinInlineCapacity, AllocPolicy, kElemIsPod>;

  friend struct detail::VectorTesting;

  MOZ_MUST_USE bool growStorageBy(size_t aIncr);
  MOZ_MUST_USE bool convertToHeapStorage(size_t aNewCap);
  MOZ_MUST_USE bool maybeCheckSimulatedOOM(size_t aRequestedSize);

  /* magic constants */

  static const int kMaxInlineBytes = 1024;

  /* compute constants */

  /*
   * Consider element size to be 1 for buffer sizing if there are 0 inline
   * elements.  This allows us to compile when the definition of the element
   * type is not visible here.
   *
   * Explicit specialization is only allowed at namespace scope, so in order
   * to keep everything here, we use a dummy template parameter with partial
   * specialization.
   */
  template<int M, int Dummy>
  struct ElemSize
  {
    static const size_t value = sizeof(T);
  };
  template<int Dummy>
  struct ElemSize<0, Dummy>
  {
    static const size_t value = 1;
  };

  static const size_t kInlineCapacity =
    tl::Min<MinInlineCapacity, kMaxInlineBytes / ElemSize<MinInlineCapacity, 0>::value>::value;

  /* Calculate inline buffer size; avoid 0-sized array. */
  static const size_t kInlineBytes =
    tl::Max<1, kInlineCapacity * ElemSize<MinInlineCapacity, 0>::value>::value;

  /* member data */

  /*
   * Pointer to the buffer, be it inline or heap-allocated. Only [mBegin,
   * mBegin + mLength) hold valid constructed T objects. The range [mBegin +
   * mLength, mBegin + mCapacity) holds uninitialized memory. The range
   * [mBegin + mLength, mBegin + mReserved) also holds uninitialized memory
   * previously allocated by a call to reserve().
   */
  T* mBegin;

  /* Number of elements in the vector. */
  size_t mLength;

  /* Max number of elements storable in the vector without resizing. */
  size_t mCapacity;

#ifdef DEBUG
  /* Max elements of reserved or used space in this vector. */
  size_t mReserved;
#endif

  /* Memory used for inline storage. */
  AlignedStorage<kInlineBytes> mStorage;

#ifdef DEBUG
  friend class ReentrancyGuard;
  bool mEntered;
#endif

  /* private accessors */

  bool usingInlineStorage() const
  {
    return mBegin == const_cast<Vector*>(this)->inlineStorage();
  }

  T* inlineStorage()
  {
    return static_cast<T*>(mStorage.addr());
  }

  T* beginNoCheck() const
  {
    return mBegin;
  }

  T* endNoCheck()
  {
    return mBegin + mLength;
  }

  const T* endNoCheck() const
  {
    return mBegin + mLength;
  }

#ifdef DEBUG
  /**
   * The amount of explicitly allocated space in this vector that is immediately
   * available to be filled by appending additional elements.  This value is
   * always greater than or equal to |length()| -- the vector's actual elements
   * are implicitly reserved.  This value is always less than or equal to
   * |capacity()|.  It may be explicitly increased using the |reserve()| method.
   */
  size_t reserved() const
  {
    MOZ_ASSERT(mLength <= mReserved);
    MOZ_ASSERT(mReserved <= mCapacity);
    return mReserved;
  }
#endif

  /* Append operations guaranteed to succeed due to pre-reserved space. */
  template<typename U> void internalAppend(U&& aU);
  template<typename U, size_t O, class BP>
  void internalAppendAll(const Vector<U, O, BP>& aU);
  void internalAppendN(const T& aT, size_t aN);
  template<typename U> void internalAppend(const U* aBegin, size_t aLength);

public:
  static const size_t sMaxInlineStorage = MinInlineCapacity;

  typedef T ElementType;

  explicit Vector(AllocPolicy = AllocPolicy());
  Vector(Vector&&); /* Move constructor. */
  Vector& operator=(Vector&&); /* Move assignment. */
  ~Vector();

  /* accessors */

  const AllocPolicy& allocPolicy() const { return *this; }

  AllocPolicy& allocPolicy() { return *this; }

  enum { InlineLength = MinInlineCapacity };

  size_t length() const { return mLength; }

  bool empty() const { return mLength == 0; }

  size_t capacity() const { return mCapacity; }

  T* begin()
  {
    MOZ_ASSERT(!mEntered);
    return mBegin;
  }

  const T* begin() const
  {
    MOZ_ASSERT(!mEntered);
    return mBegin;
  }

  T* end()
  {
    MOZ_ASSERT(!mEntered);
    return mBegin + mLength;
  }

  const T* end() const
  {
    MOZ_ASSERT(!mEntered);
    return mBegin + mLength;
  }

  T& operator[](size_t aIndex)
  {
    MOZ_ASSERT(!mEntered);
    MOZ_ASSERT(aIndex < mLength);
    return begin()[aIndex];
  }

  const T& operator[](size_t aIndex) const
  {
    MOZ_ASSERT(!mEntered);
    MOZ_ASSERT(aIndex < mLength);
    return begin()[aIndex];
  }

  T& back()
  {
    MOZ_ASSERT(!mEntered);
    MOZ_ASSERT(!empty());
    return *(end() - 1);
  }

  const T& back() const
  {
    MOZ_ASSERT(!mEntered);
    MOZ_ASSERT(!empty());
    return *(end() - 1);
  }

  class Range
  {
    friend class Vector;
    T* mCur;
    T* mEnd;
    Range(T* aCur, T* aEnd)
      : mCur(aCur)
      , mEnd(aEnd)
    {
      MOZ_ASSERT(aCur <= aEnd);
    }

  public:
    bool empty() const { return mCur == mEnd; }
    size_t remain() const { return PointerRangeSize(mCur, mEnd); }
    T& front() const { MOZ_ASSERT(!empty()); return *mCur; }
    void popFront() { MOZ_ASSERT(!empty()); ++mCur; }
    T popCopyFront() { MOZ_ASSERT(!empty()); return *mCur++; }
  };

  class ConstRange
  {
    friend class Vector;
    const T* mCur;
    const T* mEnd;
    ConstRange(const T* aCur, const T* aEnd)
      : mCur(aCur)
      , mEnd(aEnd)
    {
      MOZ_ASSERT(aCur <= aEnd);
    }

  public:
    bool empty() const { return mCur == mEnd; }
    size_t remain() const { return PointerRangeSize(mCur, mEnd); }
    const T& front() const { MOZ_ASSERT(!empty()); return *mCur; }
    void popFront() { MOZ_ASSERT(!empty()); ++mCur; }
    T popCopyFront() { MOZ_ASSERT(!empty()); return *mCur++; }
  };

  Range all() { return Range(begin(), end()); }
  ConstRange all() const { return ConstRange(begin(), end()); }

  /* mutators */

  /**
   * Reverse the order of the elements in the vector in place.
   */
  void reverse();

  /**
   * Given that the vector is empty, grow the internal capacity to |aRequest|,
   * keeping the length 0.
   */
  MOZ_MUST_USE bool initCapacity(size_t aRequest);

  /**
   * Given that the vector is empty, grow the internal capacity and length to
   * |aRequest| leaving the elements' memory completely uninitialized (with all
   * the associated hazards and caveats). This avoids the usual allocation-size
   * rounding that happens in resize and overhead of initialization for elements
   * that are about to be overwritten.
   */
  MOZ_MUST_USE bool initLengthUninitialized(size_t aRequest);

  /**
   * If reserve(aRequest) succeeds and |aRequest >= length()|, then appending
   * |aRequest - length()| elements, in any sequence of append/appendAll calls,
   * is guaranteed to succeed.
   *
   * A request to reserve an amount less than the current length does not affect
   * reserved space.
   */
  MOZ_MUST_USE bool reserve(size_t aRequest);

  /**
   * Destroy elements in the range [end() - aIncr, end()). Does not deallocate
   * or unreserve storage for those elements.
   */
  void shrinkBy(size_t aIncr);

  /**
   * Destroy elements in the range [aNewLength, end()). Does not deallocate
   * or unreserve storage for those elements.
   */
  void shrinkTo(size_t aNewLength);

  /** Grow the vector by aIncr elements. */
  MOZ_MUST_USE bool growBy(size_t aIncr);

  /** Call shrinkBy or growBy based on whether newSize > length(). */
  MOZ_MUST_USE bool resize(size_t aNewLength);

  /**
   * Increase the length of the vector, but don't initialize the new elements
   * -- leave them as uninitialized memory.
   */
  MOZ_MUST_USE bool growByUninitialized(size_t aIncr);
  void infallibleGrowByUninitialized(size_t aIncr);
  MOZ_MUST_USE bool resizeUninitialized(size_t aNewLength);

  /** Shorthand for shrinkBy(length()). */
  void clear();

  /** Clears and releases any heap-allocated storage. */
  void clearAndFree();

  /**
   * Calls the AllocPolicy's pod_realloc to release excess capacity. Since
   * realloc is only safe on PODs, this method fails to compile if IsPod<T>
   * is false.
   */
  void podResizeToFit();

  /**
   * If true, appending |aNeeded| elements won't reallocate elements storage.
   * This *doesn't* mean that infallibleAppend may be used!  You still must
   * reserve the extra space, even if this method indicates that appends won't
   * need to reallocate elements storage.
   */
  bool canAppendWithoutRealloc(size_t aNeeded) const;

  /** Potentially fallible append operations. */

  /**
   * This can take either a T& or a T&&. Given a T&&, it moves |aU| into the
   * vector, instead of copying it. If it fails, |aU| is left unmoved. ("We are
   * not amused.")
   */
  template<typename U> MOZ_MUST_USE bool append(U&& aU);

  /**
   * Construct a T in-place as a new entry at the end of this vector.
   */
  template<typename... Args>
  MOZ_MUST_USE bool emplaceBack(Args&&... aArgs)
  {
    if (!growByUninitialized(1))
      return false;
    Impl::new_(&back(), Forward<Args>(aArgs)...);
    return true;
  }

  template<typename U, size_t O, class BP>
  MOZ_MUST_USE bool appendAll(const Vector<U, O, BP>& aU);
  MOZ_MUST_USE bool appendN(const T& aT, size_t aN);
  template<typename U> MOZ_MUST_USE bool append(const U* aBegin, const U* aEnd);
  template<typename U> MOZ_MUST_USE bool append(const U* aBegin, size_t aLength);

  /*
   * Guaranteed-infallible append operations for use upon vectors whose
   * memory has been pre-reserved.  Don't use this if you haven't reserved the
   * memory!
   */
  template<typename U> void infallibleAppend(U&& aU)
  {
    internalAppend(Forward<U>(aU));
  }
  void infallibleAppendN(const T& aT, size_t aN)
  {
    internalAppendN(aT, aN);
  }
  template<typename U> void infallibleAppend(const U* aBegin, const U* aEnd)
  {
    internalAppend(aBegin, PointerRangeSize(aBegin, aEnd));
  }
  template<typename U> void infallibleAppend(const U* aBegin, size_t aLength)
  {
    internalAppend(aBegin, aLength);
  }
  template<typename... Args>
  void infallibleEmplaceBack(Args&&... aArgs)
  {
    infallibleGrowByUninitialized(1);
    Impl::new_(&back(), Forward<Args>(aArgs)...);
  }

  void popBack();

  T popCopy();

  /**
   * If elements are stored in-place, return nullptr and leave this vector
   * unmodified.
   *
   * Otherwise return this vector's elements buffer, and clear this vector as if
   * by clearAndFree(). The caller now owns the buffer and is responsible for
   * deallocating it consistent with this vector's AllocPolicy.
   *
   * N.B. Although a T*, only the range [0, length()) is constructed.
   */
  MOZ_MUST_USE T* extractRawBuffer();

  /**
   * If elements are stored in-place, allocate a new buffer, move this vector's
   * elements into it, and return that buffer.
   *
   * Otherwise return this vector's elements buffer. The caller now owns the
   * buffer and is responsible for deallocating it consistent with this vector's
   * AllocPolicy.
   *
   * This vector is cleared, as if by clearAndFree(), when this method
   * succeeds. This method fails and returns nullptr only if new elements buffer
   * allocation fails.
   *
   * N.B. Only the range [0, length()) of the returned buffer is constructed.
   * If any of these elements are uninitialized (as growByUninitialized
   * enables), behavior is undefined.
   */
  MOZ_MUST_USE T* extractOrCopyRawBuffer();

  /**
   * Transfer ownership of an array of objects into the vector.  The caller
   * must have allocated the array in accordance with this vector's
   * AllocPolicy.
   *
   * N.B. This call assumes that there are no uninitialized elements in the
   *      passed array.
   */
  void replaceRawBuffer(T* aP, size_t aLength);

  /**
   * Places |aVal| at position |aP|, shifting existing elements from |aP| onward
   * one position higher.  On success, |aP| should not be reused because it'll
   * be a dangling pointer if reallocation of the vector storage occurred; the
   * return value should be used instead.  On failure, nullptr is returned.
   *
   * Example usage:
   *
   *   if (!(p = vec.insert(p, val))) {
   *     <handle failure>
   *   }
   *   <keep working with p>
   *
   * This is inherently a linear-time operation.  Be careful!
   */
  template<typename U>
  MOZ_MUST_USE T* insert(T* aP, U&& aVal);

  /**
   * Removes the element |aT|, which must fall in the bounds [begin, end),
   * shifting existing elements from |aT + 1| onward one position lower.
   */
  void erase(T* aT);

  /**
   * Removes the elements [|aBegin|, |aEnd|), which must fall in the bounds
   * [begin, end), shifting existing elements from |aEnd + 1| onward to aBegin's
   * old position.
   */
  void erase(T* aBegin, T* aEnd);

  /**
   * Measure the size of the vector's heap-allocated storage.
   */
  size_t sizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const;

  /**
   * Like sizeOfExcludingThis, but also measures the size of the vector
   * object (which must be heap-allocated) itself.
   */
  size_t sizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const;

  void swap(Vector& aOther);

private:
  Vector(const Vector&) = delete;
  void operator=(const Vector&) = delete;
};

/* This does the re-entrancy check plus several other sanity checks. */
#define MOZ_REENTRANCY_GUARD_ET_AL \
  ReentrancyGuard g(*this); \
  MOZ_ASSERT_IF(usingInlineStorage(), mCapacity == kInlineCapacity); \
  MOZ_ASSERT(reserved() <= mCapacity); \
  MOZ_ASSERT(mLength <= reserved()); \
  MOZ_ASSERT(mLength <= mCapacity)

/* Vector Implementation */

template<typename T, size_t N, class AP>
MOZ_ALWAYS_INLINE
Vector<T, N, AP>::Vector(AP aAP)
  : AP(aAP)
  , mLength(0)
  , mCapacity(kInlineCapacity)
#ifdef DEBUG
  , mReserved(0)
  , mEntered(false)
#endif
{
  mBegin = static_cast<T*>(mStorage.addr());
}

/* Move constructor. */
template<typename T, size_t N, class AllocPolicy>
MOZ_ALWAYS_INLINE
Vector<T, N, AllocPolicy>::Vector(Vector&& aRhs)
  : AllocPolicy(Move(aRhs))
#ifdef DEBUG
  , mEntered(false)
#endif
{
  mLength = aRhs.mLength;
  mCapacity = aRhs.mCapacity;
#ifdef DEBUG
  mReserved = aRhs.mReserved;
#endif

  if (aRhs.usingInlineStorage()) {
    /* We can't move the buffer over in this case, so copy elements. */
    mBegin = static_cast<T*>(mStorage.addr());
    Impl::moveConstruct(mBegin, aRhs.beginNoCheck(), aRhs.endNoCheck());
    /*
     * Leave aRhs's mLength, mBegin, mCapacity, and mReserved as they are.
     * The elements in its in-line storage still need to be destroyed.
     */
  } else {
    /*
     * Take src's buffer, and turn src into an empty vector using
     * in-line storage.
     */
    mBegin = aRhs.mBegin;
    aRhs.mBegin = static_cast<T*>(aRhs.mStorage.addr());
    aRhs.mCapacity = kInlineCapacity;
    aRhs.mLength = 0;
#ifdef DEBUG
    aRhs.mReserved = 0;
#endif
  }
}

/* Move assignment. */
template<typename T, size_t N, class AP>
MOZ_ALWAYS_INLINE Vector<T, N, AP>&
Vector<T, N, AP>::operator=(Vector&& aRhs)
{
  MOZ_ASSERT(this != &aRhs, "self-move assignment is prohibited");
  this->~Vector();
  new(KnownNotNull, this) Vector(Move(aRhs));
  return *this;
}

template<typename T, size_t N, class AP>
MOZ_ALWAYS_INLINE
Vector<T, N, AP>::~Vector()
{
  MOZ_REENTRANCY_GUARD_ET_AL;
  Impl::destroy(beginNoCheck(), endNoCheck());
  if (!usingInlineStorage()) {
    this->free_(beginNoCheck());
  }
}

template<typename T, size_t N, class AP>
MOZ_ALWAYS_INLINE void
Vector<T, N, AP>::reverse() {
  MOZ_REENTRANCY_GUARD_ET_AL;
  T* elems = mBegin;
  size_t len = mLength;
  size_t mid = len / 2;
  for (size_t i = 0; i < mid; i++) {
    Swap(elems[i], elems[len - i - 1]);
  }
}

/*
 * This function will create a new heap buffer with capacity aNewCap,
 * move all elements in the inline buffer to this new buffer,
 * and fail on OOM.
 */
template<typename T, size_t N, class AP>
inline bool
Vector<T, N, AP>::convertToHeapStorage(size_t aNewCap)
{
  MOZ_ASSERT(usingInlineStorage());

  /* Allocate buffer. */
  MOZ_ASSERT(!detail::CapacityHasExcessSpace<T>(aNewCap));
  T* newBuf = this->template pod_malloc<T>(aNewCap);
  if (MOZ_UNLIKELY(!newBuf)) {
    return false;
  }

  /* Copy inline elements into heap buffer. */
  Impl::moveConstruct(newBuf, beginNoCheck(), endNoCheck());
  Impl::destroy(beginNoCheck(), endNoCheck());

  /* Switch in heap buffer. */
  mBegin = newBuf;
  /* mLength is unchanged. */
  mCapacity = aNewCap;
  return true;
}

template<typename T, size_t N, class AP>
MOZ_NEVER_INLINE bool
Vector<T, N, AP>::growStorageBy(size_t aIncr)
{
  MOZ_ASSERT(mLength + aIncr > mCapacity);

  /*
   * When choosing a new capacity, its size should is as close to 2**N bytes
   * as possible.  2**N-sized requests are best because they are unlikely to
   * be rounded up by the allocator.  Asking for a 2**N number of elements
   * isn't as good, because if sizeof(T) is not a power-of-two that would
   * result in a non-2**N request size.
   */

  size_t newCap;

  if (aIncr == 1) {
    if (usingInlineStorage()) {
      /* This case occurs in ~70--80% of the calls to this function. */
      size_t newSize =
        tl::RoundUpPow2<(kInlineCapacity + 1) * sizeof(T)>::value;
      newCap = newSize / sizeof(T);
      goto convert;
    }

    if (mLength == 0) {
      /* This case occurs in ~0--10% of the calls to this function. */
      newCap = 1;
      goto grow;
    }

    /* This case occurs in ~15--20% of the calls to this function. */

    /*
     * Will mLength * 4 *sizeof(T) overflow?  This condition limits a vector
     * to 1GB of memory on a 32-bit system, which is a reasonable limit.  It
     * also ensures that
     *
     *   static_cast<char*>(end()) - static_cast<char*>(begin())
     *
     * doesn't overflow ptrdiff_t (see bug 510319).
     */
    if (MOZ_UNLIKELY(mLength & tl::MulOverflowMask<4 * sizeof(T)>::value)) {
      this->reportAllocOverflow();
      return false;
    }

    /*
     * If we reach here, the existing capacity will have a size that is already
     * as close to 2^N as sizeof(T) will allow.  Just double the capacity, and
     * then there might be space for one more element.
     */
    newCap = mLength * 2;
    if (detail::CapacityHasExcessSpace<T>(newCap)) {
      newCap += 1;
    }
  } else {
    /* This case occurs in ~2% of the calls to this function. */
    size_t newMinCap = mLength + aIncr;

    /* Did mLength + aIncr overflow?  Will newCap * sizeof(T) overflow? */
    if (MOZ_UNLIKELY(newMinCap < mLength ||
                     newMinCap & tl::MulOverflowMask<2 * sizeof(T)>::value))
    {
      this->reportAllocOverflow();
      return false;
    }

    size_t newMinSize = newMinCap * sizeof(T);
    size_t newSize = RoundUpPow2(newMinSize);
    newCap = newSize / sizeof(T);
  }

  if (usingInlineStorage()) {
convert:
    return convertToHeapStorage(newCap);
  }

grow:
  return Impl::growTo(*this, newCap);
}

template<typename T, size_t N, class AP>
inline bool
Vector<T, N, AP>::initCapacity(size_t aRequest)
{
  MOZ_ASSERT(empty());
  MOZ_ASSERT(usingInlineStorage());
  if (aRequest == 0) {
    return true;
  }
  T* newbuf = this->template pod_malloc<T>(aRequest);
  if (MOZ_UNLIKELY(!newbuf)) {
    return false;
  }
  mBegin = newbuf;
  mCapacity = aRequest;
#ifdef DEBUG
  mReserved = aRequest;
#endif
  return true;
}

template<typename T, size_t N, class AP>
inline bool
Vector<T, N, AP>::initLengthUninitialized(size_t aRequest)
{
  if (!initCapacity(aRequest)) {
    return false;
  }
  infallibleGrowByUninitialized(aRequest);
  return true;
}

template<typename T, size_t N, class AP>
inline bool
Vector<T, N, AP>::maybeCheckSimulatedOOM(size_t aRequestedSize)
{
  if (aRequestedSize <= N) {
    return true;
  }

#ifdef DEBUG
  if (aRequestedSize <= mReserved) {
    return true;
  }
#endif

  return allocPolicy().checkSimulatedOOM();
}

template<typename T, size_t N, class AP>
inline bool
Vector<T, N, AP>::reserve(size_t aRequest)
{
  MOZ_REENTRANCY_GUARD_ET_AL;
  if (aRequest > mCapacity) {
    if (MOZ_UNLIKELY(!growStorageBy(aRequest - mLength))) {
      return false;
    }
  } else if (!maybeCheckSimulatedOOM(aRequest)) {
    return false;
  }
#ifdef DEBUG
  if (aRequest > mReserved) {
    mReserved = aRequest;
  }
  MOZ_ASSERT(mLength <= mReserved);
  MOZ_ASSERT(mReserved <= mCapacity);
#endif
  return true;
}

template<typename T, size_t N, class AP>
inline void
Vector<T, N, AP>::shrinkBy(size_t aIncr)
{
  MOZ_REENTRANCY_GUARD_ET_AL;
  MOZ_ASSERT(aIncr <= mLength);
  Impl::destroy(endNoCheck() - aIncr, endNoCheck());
  mLength -= aIncr;
}

template<typename T, size_t N, class AP>
MOZ_ALWAYS_INLINE void
Vector<T, N, AP>::shrinkTo(size_t aNewLength)
{
  MOZ_ASSERT(aNewLength <= mLength);
  shrinkBy(mLength - aNewLength);
}

template<typename T, size_t N, class AP>
MOZ_ALWAYS_INLINE bool
Vector<T, N, AP>::growBy(size_t aIncr)
{
  MOZ_REENTRANCY_GUARD_ET_AL;
  if (aIncr > mCapacity - mLength) {
    if (MOZ_UNLIKELY(!growStorageBy(aIncr))) {
      return false;
    }
  } else if (!maybeCheckSimulatedOOM(mLength + aIncr)) {
    return false;
  }
  MOZ_ASSERT(mLength + aIncr <= mCapacity);
  T* newend = endNoCheck() + aIncr;
  Impl::initialize(endNoCheck(), newend);
  mLength += aIncr;
#ifdef DEBUG
  if (mLength > mReserved) {
    mReserved = mLength;
  }
#endif
  return true;
}

template<typename T, size_t N, class AP>
MOZ_ALWAYS_INLINE bool
Vector<T, N, AP>::growByUninitialized(size_t aIncr)
{
  MOZ_REENTRANCY_GUARD_ET_AL;
  if (aIncr > mCapacity - mLength) {
    if (MOZ_UNLIKELY(!growStorageBy(aIncr))) {
      return false;
    }
  } else if (!maybeCheckSimulatedOOM(mLength + aIncr)) {
    return false;
  }
#ifdef DEBUG
  if (mLength + aIncr > mReserved) {
    mReserved = mLength + aIncr;
  }
#endif
  infallibleGrowByUninitialized(aIncr);
  return true;
}

template<typename T, size_t N, class AP>
MOZ_ALWAYS_INLINE void
Vector<T, N, AP>::infallibleGrowByUninitialized(size_t aIncr)
{
  MOZ_ASSERT(mLength + aIncr <= reserved());
  mLength += aIncr;
}

template<typename T, size_t N, class AP>
inline bool
Vector<T, N, AP>::resize(size_t aNewLength)
{
  size_t curLength = mLength;
  if (aNewLength > curLength) {
    return growBy(aNewLength - curLength);
  }
  shrinkBy(curLength - aNewLength);
  return true;
}

template<typename T, size_t N, class AP>
MOZ_ALWAYS_INLINE bool
Vector<T, N, AP>::resizeUninitialized(size_t aNewLength)
{
  size_t curLength = mLength;
  if (aNewLength > curLength) {
    return growByUninitialized(aNewLength - curLength);
  }
  shrinkBy(curLength - aNewLength);
  return true;
}

template<typename T, size_t N, class AP>
inline void
Vector<T, N, AP>::clear()
{
  MOZ_REENTRANCY_GUARD_ET_AL;
  Impl::destroy(beginNoCheck(), endNoCheck());
  mLength = 0;
}

template<typename T, size_t N, class AP>
inline void
Vector<T, N, AP>::clearAndFree()
{
  clear();

  if (usingInlineStorage()) {
    return;
  }
  this->free_(beginNoCheck());
  mBegin = static_cast<T*>(mStorage.addr());
  mCapacity = kInlineCapacity;
#ifdef DEBUG
  mReserved = 0;
#endif
}

template<typename T, size_t N, class AP>
inline void
Vector<T, N, AP>::podResizeToFit()
{
  // This function is only defined if IsPod is true and will fail to compile
  // otherwise.
  Impl::podResizeToFit(*this);
}

template<typename T, size_t N, class AP>
inline bool
Vector<T, N, AP>::canAppendWithoutRealloc(size_t aNeeded) const
{
  return mLength + aNeeded <= mCapacity;
}

template<typename T, size_t N, class AP>
template<typename U, size_t O, class BP>
MOZ_ALWAYS_INLINE void
Vector<T, N, AP>::internalAppendAll(const Vector<U, O, BP>& aOther)
{
  internalAppend(aOther.begin(), aOther.length());
}

template<typename T, size_t N, class AP>
template<typename U>
MOZ_ALWAYS_INLINE void
Vector<T, N, AP>::internalAppend(U&& aU)
{
  MOZ_ASSERT(mLength + 1 <= mReserved);
  MOZ_ASSERT(mReserved <= mCapacity);
  Impl::new_(endNoCheck(), Forward<U>(aU));
  ++mLength;
}

template<typename T, size_t N, class AP>
MOZ_ALWAYS_INLINE bool
Vector<T, N, AP>::appendN(const T& aT, size_t aNeeded)
{
  MOZ_REENTRANCY_GUARD_ET_AL;
  if (mLength + aNeeded > mCapacity) {
    if (MOZ_UNLIKELY(!growStorageBy(aNeeded))) {
      return false;
    }
  } else if (!maybeCheckSimulatedOOM(mLength + aNeeded)) {
    return false;
  }
#ifdef DEBUG
  if (mLength + aNeeded > mReserved) {
    mReserved = mLength + aNeeded;
  }
#endif
  internalAppendN(aT, aNeeded);
  return true;
}

template<typename T, size_t N, class AP>
MOZ_ALWAYS_INLINE void
Vector<T, N, AP>::internalAppendN(const T& aT, size_t aNeeded)
{
  MOZ_ASSERT(mLength + aNeeded <= mReserved);
  MOZ_ASSERT(mReserved <= mCapacity);
  Impl::copyConstructN(endNoCheck(), aNeeded, aT);
  mLength += aNeeded;
}

template<typename T, size_t N, class AP>
template<typename U>
inline T*
Vector<T, N, AP>::insert(T* aP, U&& aVal)
{
  MOZ_ASSERT(begin() <= aP);
  MOZ_ASSERT(aP <= end());
  size_t pos = aP - begin();
  MOZ_ASSERT(pos <= mLength);
  size_t oldLength = mLength;
  if (pos == oldLength) {
    if (!append(Forward<U>(aVal))) {
      return nullptr;
    }
  } else {
    T oldBack = Move(back());
    if (!append(Move(oldBack))) {
      return nullptr;
    }
    for (size_t i = oldLength - 1; i > pos; --i) {
      (*this)[i] = Move((*this)[i - 1]);
    }
    (*this)[pos] = Forward<U>(aVal);
  }
  return begin() + pos;
}

template<typename T, size_t N, class AP>
inline void
Vector<T, N, AP>::erase(T* aIt)
{
  MOZ_ASSERT(begin() <= aIt);
  MOZ_ASSERT(aIt < end());
  while (aIt + 1 < end()) {
    *aIt = Move(*(aIt + 1));
    ++aIt;
  }
  popBack();
}

template<typename T, size_t N, class AP>
inline void
Vector<T, N, AP>::erase(T* aBegin, T* aEnd)
{
  MOZ_ASSERT(begin() <= aBegin);
  MOZ_ASSERT(aBegin <= aEnd);
  MOZ_ASSERT(aEnd <= end());
  while (aEnd < end()) {
    *aBegin++ = Move(*aEnd++);
  }
  shrinkBy(aEnd - aBegin);
}

template<typename T, size_t N, class AP>
template<typename U>
MOZ_ALWAYS_INLINE bool
Vector<T, N, AP>::append(const U* aInsBegin, const U* aInsEnd)
{
  MOZ_REENTRANCY_GUARD_ET_AL;
  size_t aNeeded = PointerRangeSize(aInsBegin, aInsEnd);
  if (mLength + aNeeded > mCapacity) {
    if (MOZ_UNLIKELY(!growStorageBy(aNeeded))) {
      return false;
    }
  } else if (!maybeCheckSimulatedOOM(mLength + aNeeded)) {
      return false;
  }
#ifdef DEBUG
  if (mLength + aNeeded > mReserved) {
    mReserved = mLength + aNeeded;
  }
#endif
  internalAppend(aInsBegin, aNeeded);
  return true;
}

template<typename T, size_t N, class AP>
template<typename U>
MOZ_ALWAYS_INLINE void
Vector<T, N, AP>::internalAppend(const U* aInsBegin, size_t aInsLength)
{
  MOZ_ASSERT(mLength + aInsLength <= mReserved);
  MOZ_ASSERT(mReserved <= mCapacity);
  Impl::copyConstruct(endNoCheck(), aInsBegin, aInsBegin + aInsLength);
  mLength += aInsLength;
}

template<typename T, size_t N, class AP>
template<typename U>
MOZ_ALWAYS_INLINE bool
Vector<T, N, AP>::append(U&& aU)
{
  MOZ_REENTRANCY_GUARD_ET_AL;
  if (mLength == mCapacity) {
    if (MOZ_UNLIKELY(!growStorageBy(1))) {
      return false;
    }
  } else if (!maybeCheckSimulatedOOM(mLength + 1)) {
      return false;
  }
#ifdef DEBUG
  if (mLength + 1 > mReserved) {
    mReserved = mLength + 1;
  }
#endif
  internalAppend(Forward<U>(aU));
  return true;
}

template<typename T, size_t N, class AP>
template<typename U, size_t O, class BP>
MOZ_ALWAYS_INLINE bool
Vector<T, N, AP>::appendAll(const Vector<U, O, BP>& aOther)
{
  return append(aOther.begin(), aOther.length());
}

template<typename T, size_t N, class AP>
template<class U>
MOZ_ALWAYS_INLINE bool
Vector<T, N, AP>::append(const U* aInsBegin, size_t aInsLength)
{
  return append(aInsBegin, aInsBegin + aInsLength);
}

template<typename T, size_t N, class AP>
MOZ_ALWAYS_INLINE void
Vector<T, N, AP>::popBack()
{
  MOZ_REENTRANCY_GUARD_ET_AL;
  MOZ_ASSERT(!empty());
  --mLength;
  endNoCheck()->~T();
}

template<typename T, size_t N, class AP>
MOZ_ALWAYS_INLINE T
Vector<T, N, AP>::popCopy()
{
  T ret = back();
  popBack();
  return ret;
}

template<typename T, size_t N, class AP>
inline T*
Vector<T, N, AP>::extractRawBuffer()
{
  MOZ_REENTRANCY_GUARD_ET_AL;

  if (usingInlineStorage()) {
    return nullptr;
  }

  T* ret = mBegin;
  mBegin = static_cast<T*>(mStorage.addr());
  mLength = 0;
  mCapacity = kInlineCapacity;
#ifdef DEBUG
  mReserved = 0;
#endif
  return ret;
}

template<typename T, size_t N, class AP>
inline T*
Vector<T, N, AP>::extractOrCopyRawBuffer()
{
  if (T* ret = extractRawBuffer()) {
    return ret;
  }

  MOZ_REENTRANCY_GUARD_ET_AL;

  T* copy = this->template pod_malloc<T>(mLength);
  if (!copy) {
    return nullptr;
  }

  Impl::moveConstruct(copy, beginNoCheck(), endNoCheck());
  Impl::destroy(beginNoCheck(), endNoCheck());
  mBegin = static_cast<T*>(mStorage.addr());
  mLength = 0;
  mCapacity = kInlineCapacity;
#ifdef DEBUG
  mReserved = 0;
#endif
  return copy;
}

template<typename T, size_t N, class AP>
inline void
Vector<T, N, AP>::replaceRawBuffer(T* aP, size_t aLength)
{
  MOZ_REENTRANCY_GUARD_ET_AL;

  /* Destroy what we have. */
  Impl::destroy(beginNoCheck(), endNoCheck());
  if (!usingInlineStorage()) {
    this->free_(beginNoCheck());
  }

  /* Take in the new buffer. */
  if (aLength <= kInlineCapacity) {
    /*
     * We convert to inline storage if possible, even though aP might
     * otherwise be acceptable.  Maybe this behaviour should be
     * specifiable with an argument to this function.
     */
    mBegin = static_cast<T*>(mStorage.addr());
    mLength = aLength;
    mCapacity = kInlineCapacity;
    Impl::moveConstruct(mBegin, aP, aP + aLength);
    Impl::destroy(aP, aP + aLength);
    this->free_(aP);
  } else {
    mBegin = aP;
    mLength = aLength;
    mCapacity = aLength;
  }
#ifdef DEBUG
  mReserved = aLength;
#endif
}

template<typename T, size_t N, class AP>
inline size_t
Vector<T, N, AP>::sizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
{
  return usingInlineStorage() ? 0 : aMallocSizeOf(beginNoCheck());
}

template<typename T, size_t N, class AP>
inline size_t
Vector<T, N, AP>::sizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const
{
  return aMallocSizeOf(this) + sizeOfExcludingThis(aMallocSizeOf);
}

template<typename T, size_t N, class AP>
inline void
Vector<T, N, AP>::swap(Vector& aOther)
{
  static_assert(N == 0,
                "still need to implement this for N != 0");

  // This only works when inline storage is always empty.
  if (!usingInlineStorage() && aOther.usingInlineStorage()) {
    aOther.mBegin = mBegin;
    mBegin = inlineStorage();
  } else if (usingInlineStorage() && !aOther.usingInlineStorage()) {
    mBegin = aOther.mBegin;
    aOther.mBegin = aOther.inlineStorage();
  } else if (!usingInlineStorage() && !aOther.usingInlineStorage()) {
    Swap(mBegin, aOther.mBegin);
  } else {
    // This case is a no-op, since we'd set both to use their inline storage.
  }

  Swap(mLength, aOther.mLength);
  Swap(mCapacity, aOther.mCapacity);
#ifdef DEBUG
  Swap(mReserved, aOther.mReserved);
#endif
}

} // namespace mozilla

#ifdef _MSC_VER
#pragma warning(pop)
#endif

#endif /* mozilla_Vector_h */