summaryrefslogtreecommitdiffstats
path: root/js/src/vm/GlobalObject.h
blob: 011f90aa16af612fe9fe3a0693bb6e013cf461f2 (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
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 * 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/. */

#ifndef vm_GlobalObject_h
#define vm_GlobalObject_h

#include "jsarray.h"
#include "jsbool.h"
#include "jsexn.h"
#include "jsfun.h"
#include "jsnum.h"

#include "builtin/RegExp.h"
#include "js/Vector.h"
#include "vm/ArrayBufferObject.h"
#include "vm/ErrorObject.h"
#include "vm/RegExpStatics.h"
#include "vm/Runtime.h"

namespace js {

class Debugger;
class TypedObjectModuleObject;
class LexicalEnvironmentObject;

class SimdTypeDescr;
enum class SimdType;

/*
 * Global object slots are reserved as follows:
 *
 * [0, APPLICATION_SLOTS)
 *   Pre-reserved slots in all global objects set aside for the embedding's
 *   use. As with all reserved slots these start out as UndefinedValue() and
 *   are traced for GC purposes. Apart from that the engine never touches
 *   these slots, so the embedding can do whatever it wants with them.
 * [APPLICATION_SLOTS, APPLICATION_SLOTS + JSProto_LIMIT)
 *   Stores the original value of the constructor for the corresponding
 *   JSProtoKey.
 * [APPLICATION_SLOTS + JSProto_LIMIT, APPLICATION_SLOTS + 2 * JSProto_LIMIT)
 *   Stores the prototype, if any, for the constructor for the corresponding
 *   JSProtoKey offset from JSProto_LIMIT.
 * [APPLICATION_SLOTS + 2 * JSProto_LIMIT, RESERVED_SLOTS)
 *   Various one-off values: ES5 13.2.3's [[ThrowTypeError]], RegExp statics,
 *   the original eval for this global object (implementing |var eval =
 *   otherWindow.eval; eval(...)| as an indirect eval), a bit indicating
 *   whether this object has been cleared (see JS_ClearScope), and a cache for
 *   whether eval is allowed (per the global's Content Security Policy).
 *
 * The two JSProto_LIMIT-sized ranges are necessary to implement
 * js::FindClassObject, and spec language speaking in terms of "the original
 * Array prototype object", or "as if by the expression new Array()" referring
 * to the original Array constructor. The actual (writable and even deletable)
 * Object, Array, &c. properties are not stored in reserved slots.
 */
class GlobalObject : public NativeObject
{
    /* Count of slots set aside for application use. */
    static const unsigned APPLICATION_SLOTS = JSCLASS_GLOBAL_APPLICATION_SLOTS;

    /*
     * Count of slots to store built-in prototypes and initial visible
     * properties for the constructors.
     */
    static const unsigned STANDARD_CLASS_SLOTS = JSProto_LIMIT * 2;

    enum : unsigned {
        /* Various function values needed by the engine. */
        EVAL = APPLICATION_SLOTS + STANDARD_CLASS_SLOTS,
        CREATE_DATAVIEW_FOR_THIS,
        THROWTYPEERROR,

        /*
         * Instances of the internal createArrayFromBuffer function used by the
         * typed array code, one per typed array element type.
         */
        FROM_BUFFER_UINT8,
        FROM_BUFFER_INT8,
        FROM_BUFFER_UINT16,
        FROM_BUFFER_INT16,
        FROM_BUFFER_UINT32,
        FROM_BUFFER_INT32,
        FROM_BUFFER_FLOAT32,
        FROM_BUFFER_FLOAT64,
        FROM_BUFFER_UINT8CLAMPED,

        /* One-off properties stored after slots for built-ins. */
        LEXICAL_ENVIRONMENT,
        EMPTY_GLOBAL_SCOPE,
        ITERATOR_PROTO,
        ARRAY_ITERATOR_PROTO,
        STRING_ITERATOR_PROTO,
        REGEXP_STRING_ITERATOR_PROTO,
        LEGACY_GENERATOR_OBJECT_PROTO,
        STAR_GENERATOR_OBJECT_PROTO,
        STAR_GENERATOR_FUNCTION_PROTO,
        STAR_GENERATOR_FUNCTION,
        ASYNC_FUNCTION_PROTO,
        ASYNC_FUNCTION,
        ASYNC_ITERATOR_PROTO,
        ASYNC_FROM_SYNC_ITERATOR_PROTO,
        ASYNC_GENERATOR,
        ASYNC_GENERATOR_FUNCTION,
        ASYNC_GENERATOR_PROTO,
        MAP_ITERATOR_PROTO,
        SET_ITERATOR_PROTO,
        COLLATOR_PROTO,
        NUMBER_FORMAT_PROTO,
        DATE_TIME_FORMAT_PROTO,
        MODULE_PROTO,
        IMPORT_ENTRY_PROTO,
        EXPORT_ENTRY_PROTO,
        REGEXP_STATICS,
        WARNED_ONCE_FLAGS,
        RUNTIME_CODEGEN_ENABLED,
        DEBUGGERS,
        INTRINSICS,
        FOR_OF_PIC_CHAIN,
        WINDOW_PROXY,
        GLOBAL_THIS_RESOLVED,

        /* Total reserved-slot count for global objects. */
        RESERVED_SLOTS
    };

    /*
     * The slot count must be in the public API for JSCLASS_GLOBAL_FLAGS, and
     * we won't expose GlobalObject, so just assert that the two values are
     * synchronized.
     */
    static_assert(JSCLASS_GLOBAL_SLOT_COUNT == RESERVED_SLOTS,
                  "global object slot counts are inconsistent");

    enum WarnOnceFlag : int32_t {
        WARN_WATCH_DEPRECATED                   = 1 << 0,
        WARN_ARRAYBUFFER_SLICE_DEPRECATED       = 1 << 1,
    };

    // Emit the specified warning if the given slot in |obj|'s global isn't
    // true, then set the slot to true.  Thus calling this method warns once
    // for each global object it's called on, and every other call does
    // nothing.
    static bool
    warnOnceAbout(JSContext* cx, HandleObject obj, WarnOnceFlag flag, unsigned errorNumber);


  public:
    LexicalEnvironmentObject& lexicalEnvironment() const;
    GlobalScope& emptyGlobalScope() const;

    void setThrowTypeError(JSFunction* fun) {
        MOZ_ASSERT(getSlotRef(THROWTYPEERROR).isUndefined());
        setSlot(THROWTYPEERROR, ObjectValue(*fun));
    }

    void setOriginalEval(JSObject* evalobj) {
        MOZ_ASSERT(getSlotRef(EVAL).isUndefined());
        setSlot(EVAL, ObjectValue(*evalobj));
    }

    Value getConstructor(JSProtoKey key) const {
        MOZ_ASSERT(key <= JSProto_LIMIT);
        return getSlot(APPLICATION_SLOTS + key);
    }
    static bool skipDeselectedConstructor(JSContext* cx, JSProtoKey key);
    static bool ensureConstructor(JSContext* cx, Handle<GlobalObject*> global, JSProtoKey key);
    static bool resolveConstructor(JSContext* cx, Handle<GlobalObject*> global, JSProtoKey key);
    static bool initBuiltinConstructor(JSContext* cx, Handle<GlobalObject*> global,
                                       JSProtoKey key, HandleObject ctor, HandleObject proto);

    static bool maybeResolveGlobalThis(JSContext* cx, Handle<GlobalObject*> global, bool* resolved);

    void setConstructor(JSProtoKey key, const Value& v) {
        MOZ_ASSERT(key <= JSProto_LIMIT);
        setSlot(APPLICATION_SLOTS + key, v);
    }

    Value getPrototype(JSProtoKey key) const {
        MOZ_ASSERT(key <= JSProto_LIMIT);
        return getSlot(APPLICATION_SLOTS + JSProto_LIMIT + key);
    }

    void setPrototype(JSProtoKey key, const Value& value) {
        MOZ_ASSERT(key <= JSProto_LIMIT);
        setSlot(APPLICATION_SLOTS + JSProto_LIMIT + key, value);
    }

    bool classIsInitialized(JSProtoKey key) const {
        bool inited = !getConstructor(key).isUndefined();
        MOZ_ASSERT(inited == !getPrototype(key).isUndefined());
        return inited;
    }

    bool functionObjectClassesInitialized() const {
        bool inited = classIsInitialized(JSProto_Function);
        MOZ_ASSERT(inited == classIsInitialized(JSProto_Object));
        return inited;
    }

    /*
     * Lazy standard classes need a way to indicate they have been initialized.
     * Otherwise, when we delete them, we might accidentally recreate them via
     * a lazy initialization. We use the presence of an object in the
     * getConstructor(key) reserved slot to indicate that they've been
     * initialized.
     *
     * Note: A few builtin objects, like JSON and Math, are not constructors,
     * so getConstructor is a bit of a misnomer.
     */
    bool isStandardClassResolved(JSProtoKey key) const {
        // If the constructor is undefined, then it hasn't been initialized.
        MOZ_ASSERT(getConstructor(key).isUndefined() ||
                   getConstructor(key).isObject());
        return !getConstructor(key).isUndefined();
    }

    /*
     * Using a Handle<GlobalObject*> as a Handle<Object*> is always safe as
     * GlobalObject derives JSObject. However, with C++'s semantics, Handle<T>
     * is not related to Handle<S>, independent of how S and T are related.
     * Further, Handle stores an indirect pointer and, again because of C++'s
     * semantics, T** is not related to S**, independent of how S and T are
     * related. Since we know that this specific case is safe, we provide a
     * manual upcast operation here to do the reinterpret_cast in a known-safe
     * manner.
     */
    static HandleObject upcast(Handle<GlobalObject*> global) {
        return HandleObject::fromMarkedLocation(
                reinterpret_cast<JSObject * const*>(global.address()));
    }

  private:
    bool arrayClassInitialized() const {
        return classIsInitialized(JSProto_Array);
    }

    bool booleanClassInitialized() const {
        return classIsInitialized(JSProto_Boolean);
    }
    bool numberClassInitialized() const {
        return classIsInitialized(JSProto_Number);
    }
    bool stringClassInitialized() const {
        return classIsInitialized(JSProto_String);
    }
    bool regexpClassInitialized() const {
        return classIsInitialized(JSProto_RegExp);
    }
    bool arrayBufferClassInitialized() const {
        return classIsInitialized(JSProto_ArrayBuffer);
    }
    bool sharedArrayBufferClassInitialized() const {
        return classIsInitialized(JSProto_SharedArrayBuffer);
    }
    bool errorClassesInitialized() const {
        return classIsInitialized(JSProto_Error);
    }
    bool dataViewClassInitialized() const {
        return classIsInitialized(JSProto_DataView);
    }

    Value createArrayFromBufferHelper(uint32_t slot) const {
        MOZ_ASSERT(FROM_BUFFER_UINT8 <= slot && slot <= FROM_BUFFER_UINT8CLAMPED);
        return getSlot(slot);
    }

    void setCreateArrayFromBufferHelper(uint32_t slot, Handle<JSFunction*> fun) {
        MOZ_ASSERT(getSlotRef(slot).isUndefined());
        setSlot(slot, ObjectValue(*fun));
    }

  public:
    /* XXX Privatize me! */
    void setCreateDataViewForThis(Handle<JSFunction*> fun) {
        MOZ_ASSERT(getSlotRef(CREATE_DATAVIEW_FOR_THIS).isUndefined());
        setSlot(CREATE_DATAVIEW_FOR_THIS, ObjectValue(*fun));
    }

    template<typename T>
    inline void setCreateArrayFromBuffer(Handle<JSFunction*> fun);

  private:
    // Disallow use of unqualified JSObject::create in GlobalObject.
    static GlobalObject* create(...) = delete;

    friend struct ::JSRuntime;
    static GlobalObject* createInternal(JSContext* cx, const Class* clasp);

  public:
    static GlobalObject*
    new_(JSContext* cx, const Class* clasp, JSPrincipals* principals,
         JS::OnNewGlobalHookOption hookOption, const JS::CompartmentOptions& options);

    /*
     * Create a constructor function with the specified name and length using
     * ctor, a method which creates objects with the given class.
     */
    static JSFunction*
    createConstructor(JSContext* cx,  JSNative ctor, JSAtom* name, unsigned length,
                      gc::AllocKind kind = gc::AllocKind::FUNCTION,
                      const JSJitInfo* jitInfo = nullptr);

    /*
     * Create an object to serve as [[Prototype]] for instances of the given
     * class, using |Object.prototype| as its [[Prototype]].  Users creating
     * prototype objects with particular internal structure (e.g. reserved
     * slots guaranteed to contain values of particular types) must immediately
     * complete the minimal initialization to make the returned object safe to
     * touch.
     */
    static NativeObject*
    createBlankPrototype(JSContext* cx, Handle<GlobalObject*> global, const js::Class* clasp);

    /*
     * Identical to createBlankPrototype, but uses proto as the [[Prototype]]
     * of the returned blank prototype.
     */
    static NativeObject*
    createBlankPrototypeInheriting(JSContext* cx, Handle<GlobalObject*> global,
                                   const js::Class* clasp, HandleObject proto);

    template <typename T>
    static T*
    createBlankPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        NativeObject* res = createBlankPrototype(cx, global, &T::class_);
        return res ? &res->template as<T>() : nullptr;
    }

    static NativeObject*
    getOrCreateObjectPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (global->functionObjectClassesInitialized())
            return &global->getPrototype(JSProto_Object).toObject().as<NativeObject>();
        if (!ensureConstructor(cx, global, JSProto_Object))
            return nullptr;
        return &global->getPrototype(JSProto_Object).toObject().as<NativeObject>();
    }

    static NativeObject*
    getOrCreateFunctionPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (global->functionObjectClassesInitialized())
            return &global->getPrototype(JSProto_Function).toObject().as<NativeObject>();
        if (!ensureConstructor(cx, global, JSProto_Object))
            return nullptr;
        return &global->getPrototype(JSProto_Function).toObject().as<NativeObject>();
    }

    static NativeObject*
    getOrCreateArrayPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_Array))
            return nullptr;
        return &global->getPrototype(JSProto_Array).toObject().as<NativeObject>();
    }

    NativeObject* maybeGetArrayPrototype() {
        if (arrayClassInitialized())
            return &getPrototype(JSProto_Array).toObject().as<NativeObject>();
        return nullptr;
    }

    static NativeObject*
    getOrCreateBooleanPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_Boolean))
            return nullptr;
        return &global->getPrototype(JSProto_Boolean).toObject().as<NativeObject>();
    }

    static NativeObject*
    getOrCreateNumberPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_Number))
            return nullptr;
        return &global->getPrototype(JSProto_Number).toObject().as<NativeObject>();
    }

    static NativeObject*
    getOrCreateStringPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_String))
            return nullptr;
        return &global->getPrototype(JSProto_String).toObject().as<NativeObject>();
    }

    static NativeObject*
    getOrCreateSymbolPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_Symbol))
            return nullptr;
        return &global->getPrototype(JSProto_Symbol).toObject().as<NativeObject>();
    }

    static NativeObject*
    getOrCreatePromisePrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_Promise))
            return nullptr;
        return &global->getPrototype(JSProto_Promise).toObject().as<NativeObject>();
    }

    static NativeObject*
    getOrCreateRegExpPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_RegExp))
            return nullptr;
        return &global->getPrototype(JSProto_RegExp).toObject().as<NativeObject>();
    }

    JSObject* maybeGetRegExpPrototype() {
        if (regexpClassInitialized())
            return &getPrototype(JSProto_RegExp).toObject();
        return nullptr;
    }

    static NativeObject*
    getOrCreateSavedFramePrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_SavedFrame))
            return nullptr;
        return &global->getPrototype(JSProto_SavedFrame).toObject().as<NativeObject>();
    }

    static JSObject*
    getOrCreateArrayBufferPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_ArrayBuffer))
            return nullptr;
        return &global->getPrototype(JSProto_ArrayBuffer).toObject();
    }

    static JSObject*
    getOrCreateSharedArrayBufferPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_SharedArrayBuffer))
            return nullptr;
        return &global->getPrototype(JSProto_SharedArrayBuffer).toObject();
    }

    static JSObject*
    getOrCreateCustomErrorPrototype(JSContext* cx, Handle<GlobalObject*> global,
                                    JSExnType exnType)
    {
        JSProtoKey key = GetExceptionProtoKey(exnType);
        if (!ensureConstructor(cx, global, key))
            return nullptr;
        return &global->getPrototype(key).toObject();
    }

    static JSFunction*
    getOrCreateErrorConstructor(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_Error))
            return nullptr;
        return &global->getConstructor(JSProto_Error).toObject().as<JSFunction>();
    }

    static JSObject*
    getOrCreateErrorPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return getOrCreateCustomErrorPrototype(cx, global, JSEXN_ERR);
    }

    static NativeObject*
    getOrCreateSetPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_Set))
            return nullptr;
        return &global->getPrototype(JSProto_Set).toObject().as<NativeObject>();
    }

    static NativeObject*
    getOrCreateWeakSetPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_WeakSet))
            return nullptr;
        return &global->getPrototype(JSProto_WeakSet).toObject().as<NativeObject>();
    }

    static JSObject*
    getOrCreateIntlObject(JSContext* cx, Handle<GlobalObject*> global) {
        return getOrCreateObject(cx, global, APPLICATION_SLOTS + JSProto_Intl, initIntlObject);
    }

    static JSObject*
    getOrCreateTypedObjectModule(JSContext* cx, Handle<GlobalObject*> global) {
        return getOrCreateObject(cx, global, APPLICATION_SLOTS + JSProto_TypedObject,
                                 initTypedObjectModule);
    }

    static JSObject*
    getOrCreateSimdGlobalObject(JSContext* cx, Handle<GlobalObject*> global) {
        return getOrCreateObject(cx, global, APPLICATION_SLOTS + JSProto_SIMD, initSimdObject);
    }

    // Get the type descriptor for one of the SIMD types.
    // simdType is one of the JS_SIMDTYPEREPR_* constants.
    // Implemented in builtin/SIMD.cpp.
    static SimdTypeDescr*
    getOrCreateSimdTypeDescr(JSContext* cx, Handle<GlobalObject*> global, SimdType simdType);

    TypedObjectModuleObject& getTypedObjectModule() const;

    JSObject* getLegacyIteratorPrototype() {
        return &getPrototype(JSProto_Iterator).toObject();
    }

    static JSObject*
    getOrCreateCollatorPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return getOrCreateObject(cx, global, COLLATOR_PROTO, initIntlObject);
    }

    static JSObject*
    getOrCreateNumberFormatPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return getOrCreateObject(cx, global, NUMBER_FORMAT_PROTO, initIntlObject);
    }

    static JSObject*
    getOrCreateDateTimeFormatPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return getOrCreateObject(cx, global, DATE_TIME_FORMAT_PROTO, initIntlObject);
    }

    static bool ensureModulePrototypesCreated(JSContext *cx, Handle<GlobalObject*> global);

    JSObject* maybeGetModulePrototype() {
        Value value = getSlot(MODULE_PROTO);
        return value.isUndefined() ? nullptr : &value.toObject();
    }

    JSObject* maybeGetImportEntryPrototype() {
        Value value = getSlot(IMPORT_ENTRY_PROTO);
        return value.isUndefined() ? nullptr : &value.toObject();
    }

    JSObject* maybeGetExportEntryPrototype() {
        Value value = getSlot(EXPORT_ENTRY_PROTO);
        return value.isUndefined() ? nullptr : &value.toObject();
    }

    JSObject* getModulePrototype() {
        JSObject* proto = maybeGetModulePrototype();
        MOZ_ASSERT(proto);
        return proto;
    }

    JSObject* getImportEntryPrototype() {
        JSObject* proto = maybeGetImportEntryPrototype();
        MOZ_ASSERT(proto);
        return proto;
    }

    JSObject* getExportEntryPrototype() {
        JSObject* proto = maybeGetExportEntryPrototype();
        MOZ_ASSERT(proto);
        return proto;
    }

    static JSFunction*
    getOrCreateTypedArrayConstructor(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_TypedArray))
            return nullptr;
        return &global->getConstructor(JSProto_TypedArray).toObject().as<JSFunction>();
    }

    static JSObject*
    getOrCreateTypedArrayPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_TypedArray))
            return nullptr;
        return &global->getPrototype(JSProto_TypedArray).toObject();
    }

  private:
    typedef bool (*ObjectInitOp)(JSContext* cx, Handle<GlobalObject*> global);

    static JSObject*
    getOrCreateObject(JSContext* cx, Handle<GlobalObject*> global, unsigned slot,
                      ObjectInitOp init)
    {
        Value v = global->getSlotRef(slot);
        if (v.isObject())
            return &v.toObject();
        if (!init(cx, global))
            return nullptr;
        return &global->getSlot(slot).toObject();
    }

  public:
    static NativeObject*
    getOrCreateIteratorPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return MaybeNativeObject(getOrCreateObject(cx, global, ITERATOR_PROTO, initIteratorProto));
    }

    static NativeObject*
    getOrCreateArrayIteratorPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return MaybeNativeObject(getOrCreateObject(cx, global, ARRAY_ITERATOR_PROTO,
                                                   initArrayIteratorProto));
    }

    static NativeObject*
    getOrCreateStringIteratorPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return MaybeNativeObject(getOrCreateObject(cx, global, STRING_ITERATOR_PROTO,
                                                   initStringIteratorProto));
    }

    static NativeObject*
    getOrCreateRegExpStringIteratorPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return MaybeNativeObject(getOrCreateObject(cx, global, REGEXP_STRING_ITERATOR_PROTO,
                                                   initRegExpStringIteratorProto));
    }

    static NativeObject*
    getOrCreateLegacyGeneratorObjectPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return MaybeNativeObject(getOrCreateObject(cx, global, LEGACY_GENERATOR_OBJECT_PROTO,
                                                   initLegacyGeneratorProto));
    }

    static NativeObject*
    getOrCreateStarGeneratorObjectPrototype(JSContext* cx, Handle<GlobalObject*> global)
    {
        return MaybeNativeObject(getOrCreateObject(cx, global, STAR_GENERATOR_OBJECT_PROTO,
                                                   initStarGenerators));
    }

    static NativeObject*
    getOrCreateStarGeneratorFunctionPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return MaybeNativeObject(getOrCreateObject(cx, global, STAR_GENERATOR_FUNCTION_PROTO,
                                                   initStarGenerators));
    }

    static JSObject*
    getOrCreateStarGeneratorFunction(JSContext* cx, Handle<GlobalObject*> global) {
        return getOrCreateObject(cx, global, STAR_GENERATOR_FUNCTION, initStarGenerators);
    }

    static NativeObject*
    getOrCreateAsyncFunctionPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return MaybeNativeObject(getOrCreateObject(cx, global, ASYNC_FUNCTION_PROTO,
                                                   initAsyncFunction));
    }

    static JSObject*
    getOrCreateAsyncFunction(JSContext* cx, Handle<GlobalObject*> global) {
        return getOrCreateObject(cx, global, ASYNC_FUNCTION, initAsyncFunction);
    }

    static NativeObject*
    getOrCreateAsyncIteratorPrototype(JSContext* cx, Handle<GlobalObject*> global)
    {
        return MaybeNativeObject(getOrCreateObject(cx, global, ASYNC_ITERATOR_PROTO,
                                                   initAsyncGenerators));
    }

    static NativeObject*
    getOrCreateAsyncFromSyncIteratorPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return MaybeNativeObject(getOrCreateObject(cx, global, ASYNC_FROM_SYNC_ITERATOR_PROTO,
                                                   initAsyncGenerators));
    }

    static NativeObject*
    getOrCreateAsyncGenerator(JSContext* cx, Handle<GlobalObject*> global) {
        return MaybeNativeObject(getOrCreateObject(cx, global, ASYNC_GENERATOR,
                                                   initAsyncGenerators));
    }

    static JSObject*
    getOrCreateAsyncGeneratorFunction(JSContext* cx, Handle<GlobalObject*> global) {
        return getOrCreateObject(cx, global, ASYNC_GENERATOR_FUNCTION, initAsyncGenerators);
    }

    static NativeObject*
    getOrCreateAsyncGeneratorPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return MaybeNativeObject(getOrCreateObject(cx, global, ASYNC_GENERATOR_PROTO,
                                                   initAsyncGenerators));
    }

    static JSObject*
    getOrCreateMapIteratorPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return getOrCreateObject(cx, global, MAP_ITERATOR_PROTO, initMapIteratorProto);
    }

    static JSObject*
    getOrCreateSetIteratorPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        return getOrCreateObject(cx, global, SET_ITERATOR_PROTO, initSetIteratorProto);
    }

    static JSObject*
    getOrCreateDataViewPrototype(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_DataView))
            return nullptr;
        return &global->getPrototype(JSProto_DataView).toObject();
    }

    static JSFunction*
    getOrCreatePromiseConstructor(JSContext* cx, Handle<GlobalObject*> global) {
        if (!ensureConstructor(cx, global, JSProto_Promise))
            return nullptr;
        return &global->getConstructor(JSProto_Promise).toObject().as<JSFunction>();
    }

    static NativeObject* getIntrinsicsHolder(JSContext* cx, Handle<GlobalObject*> global);

    bool maybeExistingIntrinsicValue(PropertyName* name, Value* vp) {
        Value slot = getReservedSlot(INTRINSICS);
        // If we're in the self-hosting compartment itself, the
        // intrinsics-holder isn't initialized at this point.
        if (slot.isUndefined()) {
            *vp = UndefinedValue();
            return false;
        }

        NativeObject* holder = &slot.toObject().as<NativeObject>();
        Shape* shape = holder->lookupPure(name);
        if (!shape) {
            *vp = UndefinedValue();
            return false;
        }

        *vp = holder->getSlot(shape->slot());
        return true;
    }

    Value existingIntrinsicValue(PropertyName* name) {
        Value val;
        mozilla::DebugOnly<bool> exists = maybeExistingIntrinsicValue(name, &val);
        MOZ_ASSERT(exists, "intrinsic must already have been added to holder");

        return val;
    }

    static bool
    maybeGetIntrinsicValue(JSContext* cx, Handle<GlobalObject*> global, Handle<PropertyName*> name,
                           MutableHandleValue vp, bool* exists)
    {
        NativeObject* holder = getIntrinsicsHolder(cx, global);
        if (!holder)
            return false;

        if (Shape* shape = holder->lookupPure(name)) {
            vp.set(holder->getSlot(shape->slot()));
            *exists = true;
        } else {
            *exists = false;
        }

        return true;
    }

    static bool
    getIntrinsicValue(JSContext* cx, Handle<GlobalObject*> global,
                      HandlePropertyName name, MutableHandleValue value)
    {
        bool exists = false;
        if (!GlobalObject::maybeGetIntrinsicValue(cx, global, name, value, &exists))
            return false;
        if (exists)
            return true;
        if (!cx->runtime()->cloneSelfHostedValue(cx, name, value))
            return false;
        return GlobalObject::addIntrinsicValue(cx, global, name, value);
    }

    static bool addIntrinsicValue(JSContext* cx, Handle<GlobalObject*> global,
                                  HandlePropertyName name, HandleValue value);

    static bool setIntrinsicValue(JSContext* cx, Handle<GlobalObject*> global,
                                  HandlePropertyName name, HandleValue value)
    {
        MOZ_ASSERT(cx->runtime()->isSelfHostingGlobal(global));
        RootedObject holder(cx, GlobalObject::getIntrinsicsHolder(cx, global));
        if (!holder)
            return false;
        return SetProperty(cx, holder, name, value);
    }

    static bool getSelfHostedFunction(JSContext* cx, Handle<GlobalObject*> global,
                                      HandlePropertyName selfHostedName, HandleAtom name,
                                      unsigned nargs, MutableHandleValue funVal);

    bool hasRegExpStatics() const;
    static RegExpStatics* getRegExpStatics(ExclusiveContext* cx,
                                           Handle<GlobalObject*> global);
    RegExpStatics* getAlreadyCreatedRegExpStatics() const;

    JSObject* getThrowTypeError() const {
        const Value v = getReservedSlot(THROWTYPEERROR);
        MOZ_ASSERT(v.isObject(),
                   "attempting to access [[ThrowTypeError]] too early");
        return &v.toObject();
    }

    Value createDataViewForThis() const {
        MOZ_ASSERT(dataViewClassInitialized());
        return getSlot(CREATE_DATAVIEW_FOR_THIS);
    }

    template<typename T>
    inline Value createArrayFromBuffer() const;

    static bool isRuntimeCodeGenEnabled(JSContext* cx, Handle<GlobalObject*> global);

    // Warn about use of the deprecated watch/unwatch functions in the global
    // in which |obj| was created, if no prior warning was given.
    static bool warnOnceAboutWatch(JSContext* cx, HandleObject obj) {
        // Temporarily disabled until we've provided a watch/unwatch workaround for
        // debuggers like Firebug (bug 934669).
        //return warnOnceAbout(cx, obj, WARN_WATCH_DEPRECATED, JSMSG_OBJECT_WATCH_DEPRECATED);
        return true;
    }

    // Warn about use of the deprecated (static) ArrayBuffer.slice method.
    static bool warnOnceAboutArrayBufferSlice(JSContext* cx, HandleObject obj) {
        return warnOnceAbout(cx, obj, WARN_ARRAYBUFFER_SLICE_DEPRECATED,
                             JSMSG_ARRAYBUFFER_SLICE_DEPRECATED);
    }

    static bool getOrCreateEval(JSContext* cx, Handle<GlobalObject*> global,
                                MutableHandleObject eval);

    // Infallibly test whether the given value is the eval function for this global.
    bool valueIsEval(const Value& val);

    // Implemented in jsiter.cpp.
    static bool initIteratorProto(JSContext* cx, Handle<GlobalObject*> global);
    static bool initArrayIteratorProto(JSContext* cx, Handle<GlobalObject*> global);
    static bool initStringIteratorProto(JSContext* cx, Handle<GlobalObject*> global);
    static bool initRegExpStringIteratorProto(JSContext* cx, Handle<GlobalObject*> global);

    // Implemented in vm/GeneratorObject.cpp.
    static bool initLegacyGeneratorProto(JSContext* cx, Handle<GlobalObject*> global);
    static bool initStarGenerators(JSContext* cx, Handle<GlobalObject*> global);

    static bool initAsyncFunction(JSContext* cx, Handle<GlobalObject*> global);

    static bool initAsyncGenerators(JSContext* cx, Handle<GlobalObject*> global);

    // Implemented in builtin/MapObject.cpp.
    static bool initMapIteratorProto(JSContext* cx, Handle<GlobalObject*> global);
    static bool initSetIteratorProto(JSContext* cx, Handle<GlobalObject*> global);

    // Implemented in Intl.cpp.
    static bool initIntlObject(JSContext* cx, Handle<GlobalObject*> global);

    // Implemented in builtin/ModuleObject.cpp
    static bool initModuleProto(JSContext* cx, Handle<GlobalObject*> global);
    static bool initImportEntryProto(JSContext* cx, Handle<GlobalObject*> global);
    static bool initExportEntryProto(JSContext* cx, Handle<GlobalObject*> global);

    // Implemented in builtin/TypedObject.cpp
    static bool initTypedObjectModule(JSContext* cx, Handle<GlobalObject*> global);

    // Implemented in builtin/SIMD.cpp
    static bool initSimdObject(JSContext* cx, Handle<GlobalObject*> global);
    static bool initSimdType(JSContext* cx, Handle<GlobalObject*> global, SimdType simdType);

    static bool initStandardClasses(JSContext* cx, Handle<GlobalObject*> global);
    static bool initSelfHostingBuiltins(JSContext* cx, Handle<GlobalObject*> global,
                                        const JSFunctionSpec* builtins);

    typedef js::Vector<js::ReadBarriered<js::Debugger*>, 0, js::SystemAllocPolicy> DebuggerVector;

    /*
     * The collection of Debugger objects debugging this global. If this global
     * is not a debuggee, this returns either nullptr or an empty vector.
     */
    DebuggerVector* getDebuggers() const;

    /*
     * The same, but create the empty vector if one does not already
     * exist. Returns nullptr only on OOM.
     */
    static DebuggerVector* getOrCreateDebuggers(JSContext* cx, Handle<GlobalObject*> global);

    inline NativeObject* getForOfPICObject() {
        Value forOfPIC = getReservedSlot(FOR_OF_PIC_CHAIN);
        if (forOfPIC.isUndefined())
            return nullptr;
        return &forOfPIC.toObject().as<NativeObject>();
    }
    static NativeObject* getOrCreateForOfPICObject(JSContext* cx, Handle<GlobalObject*> global);

    JSObject* windowProxy() const {
        return &getReservedSlot(WINDOW_PROXY).toObject();
    }
    JSObject* maybeWindowProxy() const {
        Value v = getReservedSlot(WINDOW_PROXY);
        MOZ_ASSERT(v.isObject() || v.isUndefined());
        return v.isObject() ? &v.toObject() : nullptr;
    }
    void setWindowProxy(JSObject* windowProxy) {
        setReservedSlot(WINDOW_PROXY, ObjectValue(*windowProxy));
    }

    // Returns either this global's star-generator function prototype, or null
    // if that object was never created.  Dodgy; for use only in also-dodgy
    // GlobalHelperThreadState::mergeParseTaskCompartment().
    JSObject* getStarGeneratorFunctionPrototype();
};

template<>
inline void
GlobalObject::setCreateArrayFromBuffer<uint8_t>(Handle<JSFunction*> fun)
{
    setCreateArrayFromBufferHelper(FROM_BUFFER_UINT8, fun);
}

template<>
inline void
GlobalObject::setCreateArrayFromBuffer<int8_t>(Handle<JSFunction*> fun)
{
    setCreateArrayFromBufferHelper(FROM_BUFFER_INT8, fun);
}

template<>
inline void
GlobalObject::setCreateArrayFromBuffer<uint16_t>(Handle<JSFunction*> fun)
{
    setCreateArrayFromBufferHelper(FROM_BUFFER_UINT16, fun);
}

template<>
inline void
GlobalObject::setCreateArrayFromBuffer<int16_t>(Handle<JSFunction*> fun)
{
    setCreateArrayFromBufferHelper(FROM_BUFFER_INT16, fun);
}

template<>
inline void
GlobalObject::setCreateArrayFromBuffer<uint32_t>(Handle<JSFunction*> fun)
{
    setCreateArrayFromBufferHelper(FROM_BUFFER_UINT32, fun);
}

template<>
inline void
GlobalObject::setCreateArrayFromBuffer<int32_t>(Handle<JSFunction*> fun)
{
    setCreateArrayFromBufferHelper(FROM_BUFFER_INT32, fun);
}

template<>
inline void
GlobalObject::setCreateArrayFromBuffer<float>(Handle<JSFunction*> fun)
{
    setCreateArrayFromBufferHelper(FROM_BUFFER_FLOAT32, fun);
}

template<>
inline void
GlobalObject::setCreateArrayFromBuffer<double>(Handle<JSFunction*> fun)
{
    setCreateArrayFromBufferHelper(FROM_BUFFER_FLOAT64, fun);
}

template<>
inline void
GlobalObject::setCreateArrayFromBuffer<uint8_clamped>(Handle<JSFunction*> fun)
{
    setCreateArrayFromBufferHelper(FROM_BUFFER_UINT8CLAMPED, fun);
}

template<>
inline Value
GlobalObject::createArrayFromBuffer<uint8_t>() const
{
    return createArrayFromBufferHelper(FROM_BUFFER_UINT8);
}

template<>
inline Value
GlobalObject::createArrayFromBuffer<int8_t>() const
{
    return createArrayFromBufferHelper(FROM_BUFFER_INT8);
}

template<>
inline Value
GlobalObject::createArrayFromBuffer<uint16_t>() const
{
    return createArrayFromBufferHelper(FROM_BUFFER_UINT16);
}

template<>
inline Value
GlobalObject::createArrayFromBuffer<int16_t>() const
{
    return createArrayFromBufferHelper(FROM_BUFFER_INT16);
}

template<>
inline Value
GlobalObject::createArrayFromBuffer<uint32_t>() const
{
    return createArrayFromBufferHelper(FROM_BUFFER_UINT32);
}

template<>
inline Value
GlobalObject::createArrayFromBuffer<int32_t>() const
{
    return createArrayFromBufferHelper(FROM_BUFFER_INT32);
}

template<>
inline Value
GlobalObject::createArrayFromBuffer<float>() const
{
    return createArrayFromBufferHelper(FROM_BUFFER_FLOAT32);
}

template<>
inline Value
GlobalObject::createArrayFromBuffer<double>() const
{
    return createArrayFromBufferHelper(FROM_BUFFER_FLOAT64);
}

template<>
inline Value
GlobalObject::createArrayFromBuffer<uint8_clamped>() const
{
    return createArrayFromBufferHelper(FROM_BUFFER_UINT8CLAMPED);
}

/*
 * Unless otherwise specified, define ctor.prototype = proto as non-enumerable,
 * non-configurable, and non-writable; and define proto.constructor = ctor as
 * non-enumerable but configurable and writable.
 */
extern bool
LinkConstructorAndPrototype(JSContext* cx, JSObject* ctor, JSObject* proto,
                            unsigned prototypeAttrs = JSPROP_PERMANENT | JSPROP_READONLY,
                            unsigned constructorAttrs = 0);

/*
 * Define properties and/or functions on any object. Either ps or fs, or both,
 * may be null.
 */
extern bool
DefinePropertiesAndFunctions(JSContext* cx, HandleObject obj,
                             const JSPropertySpec* ps, const JSFunctionSpec* fs);

typedef HashSet<GlobalObject*, DefaultHasher<GlobalObject*>, SystemAllocPolicy> GlobalObjectSet;

extern bool
DefineToStringTag(JSContext *cx, HandleObject obj, JSAtom* tag);

/*
 * Convenience templates to generic constructor and prototype creation functions
 * for ClassSpecs.
 */

template<JSNative ctor, unsigned length, gc::AllocKind kind, const JSJitInfo* jitInfo = nullptr>
JSObject*
GenericCreateConstructor(JSContext* cx, JSProtoKey key)
{
    // Note - We duplicate the trick from ClassName() so that we don't need to
    // include jsatominlines.h here.
    PropertyName* name = (&cx->names().Null)[key];
    return GlobalObject::createConstructor(cx, ctor, name, length, kind, jitInfo);
}

inline JSObject*
GenericCreatePrototype(JSContext* cx, JSProtoKey key)
{
    MOZ_ASSERT(key != JSProto_Object);
    const Class* clasp = ProtoKeyToClass(key);
    MOZ_ASSERT(clasp);
    JSProtoKey protoKey = InheritanceProtoKeyForStandardClass(key);
    if (!GlobalObject::ensureConstructor(cx, cx->global(), protoKey))
        return nullptr;
    RootedObject parentProto(cx, &cx->global()->getPrototype(protoKey).toObject());
    return GlobalObject::createBlankPrototypeInheriting(cx, cx->global(), clasp, parentProto);
}

inline JSProtoKey
StandardProtoKeyOrNull(const JSObject* obj)
{
    return JSCLASS_CACHED_PROTO_KEY(obj->getClass());
}

JSObject*
NewSingletonObjectWithFunctionPrototype(JSContext* cx, Handle<GlobalObject*> global);

} // namespace js

template<>
inline bool
JSObject::is<js::GlobalObject>() const
{
    return !!(getClass()->flags & JSCLASS_IS_GLOBAL);
}

#endif /* vm_GlobalObject_h */