summaryrefslogtreecommitdiffstats
path: root/js/src/vm/Interpreter-inl.h
blob: 710f1d89b1a18896bc411a6e0df792b3b3fe27fe (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
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 * vim: set ts=8 sts=4 et sw=4 tw=99:
 * 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_Interpreter_inl_h
#define vm_Interpreter_inl_h

#include "vm/Interpreter.h"

#include "jscompartment.h"
#include "jsnum.h"
#include "jsstr.h"

#include "jit/Ion.h"
#include "vm/ArgumentsObject.h"

#include "jsatominlines.h"
#include "jsobjinlines.h"

#include "vm/EnvironmentObject-inl.h"
#include "vm/Stack-inl.h"
#include "vm/String-inl.h"

namespace js {

/*
 * Every possible consumer of MagicValue(JS_OPTIMIZED_ARGUMENTS) (as determined
 * by ScriptAnalysis::needsArgsObj) must check for these magic values and, when
 * one is received, act as if the value were the function's ArgumentsObject.
 * Additionally, it is possible that, after 'arguments' was copied into a
 * temporary, the arguments object has been created a some other failed guard
 * that called JSScript::argumentsOptimizationFailed. In this case, it is
 * always valid (and necessary) to replace JS_OPTIMIZED_ARGUMENTS with the real
 * arguments object.
 */
static inline bool
IsOptimizedArguments(AbstractFramePtr frame, MutableHandleValue vp)
{
    if (vp.isMagic(JS_OPTIMIZED_ARGUMENTS) && frame.script()->needsArgsObj())
        vp.setObject(frame.argsObj());
    return vp.isMagic(JS_OPTIMIZED_ARGUMENTS);
}

/*
 * One optimized consumer of MagicValue(JS_OPTIMIZED_ARGUMENTS) is f.apply.
 * However, this speculation must be guarded before calling 'apply' in case it
 * is not the builtin Function.prototype.apply.
 */
static inline bool
GuardFunApplyArgumentsOptimization(JSContext* cx, AbstractFramePtr frame, CallArgs& args)
{
    if (args.length() == 2 && IsOptimizedArguments(frame, args[1])) {
        if (!IsNativeFunction(args.calleev(), js::fun_apply)) {
            RootedScript script(cx, frame.script());
            if (!JSScript::argumentsOptimizationFailed(cx, script))
                return false;
            args[1].setObject(frame.argsObj());
        }
    }

    return true;
}

/*
 * Per ES6, lexical declarations may not be accessed in any fashion until they
 * are initialized (i.e., until the actual declaring statement is
 * executed). The various LEXICAL opcodes need to check if the slot is an
 * uninitialized let declaration, represented by the magic value
 * JS_UNINITIALIZED_LEXICAL.
 */
static inline bool
IsUninitializedLexical(const Value& val)
{
    // Use whyMagic here because JS_OPTIMIZED_ARGUMENTS could flow into here.
    return val.isMagic() && val.whyMagic() == JS_UNINITIALIZED_LEXICAL;
}

static inline bool
IsUninitializedLexicalSlot(HandleObject obj, HandleShape shape)
{
    MOZ_ASSERT(shape);
    if (obj->is<WithEnvironmentObject>())
        return false;
    // We check for IsImplicitDenseOrTypedArrayElement even though the shape
    // is always a non-indexed property because proxy hooks may return a
    // "non-native property found" shape, which happens to be encoded in the
    // same way as the "dense element" shape. See MarkNonNativePropertyFound.
    if (IsImplicitDenseOrTypedArrayElement(shape) ||
        !shape->hasSlot() ||
        !shape->hasDefaultGetter() ||
        !shape->hasDefaultSetter())
    {
        return false;
    }
    MOZ_ASSERT(obj->as<NativeObject>().containsPure(shape));
    return IsUninitializedLexical(obj->as<NativeObject>().getSlot(shape->slot()));
}

static inline void
ReportUninitializedLexical(JSContext* cx, HandlePropertyName name)
{
    ReportRuntimeLexicalError(cx, JSMSG_UNINITIALIZED_LEXICAL, name);
}

static inline void
ReportUninitializedLexical(JSContext* cx, HandleScript script, jsbytecode* pc)
{
    ReportRuntimeLexicalError(cx, JSMSG_UNINITIALIZED_LEXICAL, script, pc);
}

static inline bool
CheckUninitializedLexical(JSContext* cx, PropertyName* name_, HandleValue val)
{
    if (IsUninitializedLexical(val)) {
        RootedPropertyName name(cx, name_);
        ReportUninitializedLexical(cx, name);
        return false;
    }
    return true;
}

static inline bool
CheckUninitializedLexical(JSContext* cx, HandleScript script, jsbytecode* pc, HandleValue val)
{
    if (IsUninitializedLexical(val)) {
        ReportUninitializedLexical(cx, script, pc);
        return false;
    }
    return true;
}

static inline void
ReportRuntimeConstAssignment(JSContext* cx, HandlePropertyName name)
{
    ReportRuntimeLexicalError(cx, JSMSG_BAD_CONST_ASSIGN, name);
}

static inline void
ReportRuntimeConstAssignment(JSContext* cx, HandleScript script, jsbytecode* pc)
{
    ReportRuntimeLexicalError(cx, JSMSG_BAD_CONST_ASSIGN, script, pc);
}

inline bool
GetLengthProperty(const Value& lval, MutableHandleValue vp)
{
    /* Optimize length accesses on strings, arrays, and arguments. */
    if (lval.isString()) {
        vp.setInt32(lval.toString()->length());
        return true;
    }
    if (lval.isObject()) {
        JSObject* obj = &lval.toObject();
        if (obj->is<ArrayObject>()) {
            vp.setNumber(obj->as<ArrayObject>().length());
            return true;
        }

        if (obj->is<ArgumentsObject>()) {
            ArgumentsObject* argsobj = &obj->as<ArgumentsObject>();
            if (!argsobj->hasOverriddenLength()) {
                uint32_t length = argsobj->initialLength();
                MOZ_ASSERT(length < INT32_MAX);
                vp.setInt32(int32_t(length));
                return true;
            }
        }
    }

    return false;
}

template <bool TypeOf> inline bool
FetchName(JSContext* cx, HandleObject obj, HandleObject obj2, HandlePropertyName name,
          HandleShape shape, MutableHandleValue vp)
{
    if (!shape) {
        if (TypeOf) {
            vp.setUndefined();
            return true;
        }
        return ReportIsNotDefined(cx, name);
    }

    /* Take the slow path if shape was not found in a native object. */
    if (!obj->isNative() || !obj2->isNative()) {
        Rooted<jsid> id(cx, NameToId(name));
        if (!GetProperty(cx, obj, obj, id, vp))
            return false;
    } else {
        RootedObject normalized(cx, obj);
        if (normalized->is<WithEnvironmentObject>() && !shape->hasDefaultGetter())
            normalized = &normalized->as<WithEnvironmentObject>().object();
        if (shape->isDataDescriptor() && shape->hasDefaultGetter()) {
            /* Fast path for Object instance properties. */
            MOZ_ASSERT(shape->hasSlot());
            vp.set(obj2->as<NativeObject>().getSlot(shape->slot()));
        } else {
            if (!NativeGetExistingProperty(cx, normalized, obj2.as<NativeObject>(), shape, vp))
                return false;
        }
    }

    // We do our own explicit checking for |this|
    if (name == cx->names().dotThis)
        return true;

    // NAME operations are the slow paths already, so unconditionally check
    // for uninitialized lets.
    return CheckUninitializedLexical(cx, name, vp);
}

inline bool
FetchNameNoGC(JSObject* pobj, Shape* shape, MutableHandleValue vp)
{
    if (!shape || !pobj->isNative() || !shape->isDataDescriptor() || !shape->hasDefaultGetter())
        return false;

    vp.set(pobj->as<NativeObject>().getSlot(shape->slot()));
    return !IsUninitializedLexical(vp);
}

inline bool
GetIntrinsicOperation(JSContext* cx, jsbytecode* pc, MutableHandleValue vp)
{
    RootedPropertyName name(cx, cx->currentScript()->getName(pc));
    return GlobalObject::getIntrinsicValue(cx, cx->global(), name, vp);
}

inline bool
SetIntrinsicOperation(JSContext* cx, JSScript* script, jsbytecode* pc, HandleValue val)
{
    RootedPropertyName name(cx, script->getName(pc));
    return GlobalObject::setIntrinsicValue(cx, cx->global(), name, val);
}

inline void
SetAliasedVarOperation(JSContext* cx, JSScript* script, jsbytecode* pc,
                       EnvironmentObject& obj, EnvironmentCoordinate ec, const Value& val,
                       MaybeCheckTDZ checkTDZ)
{
    MOZ_ASSERT_IF(checkTDZ, !IsUninitializedLexical(obj.aliasedBinding(ec)));

    // Avoid computing the name if no type updates are needed, as this may be
    // expensive on scopes with large numbers of variables.
    PropertyName* name = obj.isSingleton()
                         ? EnvironmentCoordinateName(cx->caches.envCoordinateNameCache, script, pc)
                         : nullptr;

    obj.setAliasedBinding(cx, ec, name, val);
}

inline bool
SetNameOperation(JSContext* cx, JSScript* script, jsbytecode* pc, HandleObject env,
                 HandleValue val)
{
    MOZ_ASSERT(*pc == JSOP_SETNAME ||
               *pc == JSOP_STRICTSETNAME ||
               *pc == JSOP_SETGNAME ||
               *pc == JSOP_STRICTSETGNAME);
    MOZ_ASSERT_IF((*pc == JSOP_SETGNAME || *pc == JSOP_STRICTSETGNAME) &&
                  !script->hasNonSyntacticScope(),
                  env == cx->global() ||
                  env == &cx->global()->lexicalEnvironment() ||
                  env->is<RuntimeLexicalErrorObject>());

    bool strict = *pc == JSOP_STRICTSETNAME || *pc == JSOP_STRICTSETGNAME;
    RootedPropertyName name(cx, script->getName(pc));

    // In strict mode, assigning to an undeclared global variable is an
    // error. To detect this, we call NativeSetProperty directly and pass
    // Unqualified. It stores the error, if any, in |result|.
    bool ok;
    ObjectOpResult result;
    RootedId id(cx, NameToId(name));
    RootedValue receiver(cx, ObjectValue(*env));
    if (env->isUnqualifiedVarObj()) {
        RootedNativeObject varobj(cx);
        if (env->is<DebugEnvironmentProxy>())
            varobj = &env->as<DebugEnvironmentProxy>().environment().as<NativeObject>();
        else
            varobj = &env->as<NativeObject>();
        MOZ_ASSERT(!varobj->getOpsSetProperty());
        ok = NativeSetProperty(cx, varobj, id, val, receiver, Unqualified, result);
    } else {
        ok = SetProperty(cx, env, id, val, receiver, result);
    }
    return ok && result.checkStrictErrorOrWarning(cx, env, id, strict);
}

inline bool
DefLexicalOperation(JSContext* cx, Handle<LexicalEnvironmentObject*> lexicalEnv,
                    HandleObject varObj, HandlePropertyName name, unsigned attrs)
{
    // Redeclaration checks should have already been done.
    MOZ_ASSERT(CheckLexicalNameConflict(cx, lexicalEnv, varObj, name));
    RootedId id(cx, NameToId(name));
    RootedValue uninitialized(cx, MagicValue(JS_UNINITIALIZED_LEXICAL));
    return NativeDefineProperty(cx, lexicalEnv, id, uninitialized, nullptr, nullptr, attrs);
}

inline bool
DefLexicalOperation(JSContext* cx, LexicalEnvironmentObject* lexicalEnvArg,
                    JSObject* varObjArg, JSScript* script, jsbytecode* pc)
{
    MOZ_ASSERT(*pc == JSOP_DEFLET || *pc == JSOP_DEFCONST);
    RootedPropertyName name(cx, script->getName(pc));

    unsigned attrs = JSPROP_ENUMERATE | JSPROP_PERMANENT;
    if (*pc == JSOP_DEFCONST)
        attrs |= JSPROP_READONLY;

    Rooted<LexicalEnvironmentObject*> lexicalEnv(cx, lexicalEnvArg);
    RootedObject varObj(cx, varObjArg);
    MOZ_ASSERT_IF(!script->hasNonSyntacticScope(),
                  lexicalEnv == &cx->global()->lexicalEnvironment() && varObj == cx->global());

    return DefLexicalOperation(cx, lexicalEnv, varObj, name, attrs);
}

inline void
InitGlobalLexicalOperation(JSContext* cx, LexicalEnvironmentObject* lexicalEnvArg,
                           JSScript* script, jsbytecode* pc, HandleValue value)
{
    MOZ_ASSERT_IF(!script->hasNonSyntacticScope(),
                  lexicalEnvArg == &cx->global()->lexicalEnvironment());
    MOZ_ASSERT(*pc == JSOP_INITGLEXICAL);
    Rooted<LexicalEnvironmentObject*> lexicalEnv(cx, lexicalEnvArg);
    RootedShape shape(cx, lexicalEnv->lookup(cx, script->getName(pc)));
    MOZ_ASSERT(shape);
    lexicalEnv->setSlotWithType(cx, shape, value);
}

inline bool
InitPropertyOperation(JSContext* cx, JSOp op, HandleObject obj, HandleId id, HandleValue rhs)
{
  MOZ_ASSERT(obj->is<PlainObject>() || obj->is<JSFunction>());
  unsigned propAttrs = GetInitDataPropAttrs(op);
  return NativeDefineProperty(cx, obj.as<NativeObject>(), id, rhs,
                              nullptr, nullptr, propAttrs);
}

inline bool
DefVarOperation(JSContext* cx, HandleObject varobj, HandlePropertyName dn, unsigned attrs)
{
    MOZ_ASSERT(varobj->isQualifiedVarObj());

#ifdef DEBUG
    // Per spec, it is an error to redeclare a lexical binding. This should
    // have already been checked.
    if (JS_HasExtensibleLexicalEnvironment(varobj)) {
        Rooted<LexicalEnvironmentObject*> lexicalEnv(cx);
        lexicalEnv = &JS_ExtensibleLexicalEnvironment(varobj)->as<LexicalEnvironmentObject>();
        MOZ_ASSERT(CheckVarNameConflict(cx, lexicalEnv, dn));
    }
#endif

    RootedShape prop(cx);
    RootedObject obj2(cx);
    if (!LookupProperty(cx, varobj, dn, &obj2, &prop))
        return false;

    /* Steps 8c, 8d. */
    if (!prop || (obj2 != varobj && varobj->is<GlobalObject>())) {
        if (!DefineProperty(cx, varobj, dn, UndefinedHandleValue, nullptr, nullptr, attrs))
            return false;
    }

    if (varobj->is<GlobalObject>()) {
        if (!varobj->compartment()->addToVarNames(cx, dn))
            return false;
    }

    return true;
}

static MOZ_ALWAYS_INLINE bool
NegOperation(JSContext* cx, HandleScript script, jsbytecode* pc, HandleValue val,
             MutableHandleValue res)
{
    /*
     * When the operand is int jsval, INT32_FITS_IN_JSVAL(i) implies
     * INT32_FITS_IN_JSVAL(-i) unless i is 0 or INT32_MIN when the
     * results, -0.0 or INT32_MAX + 1, are double values.
     */
    int32_t i;
    if (val.isInt32() && (i = val.toInt32()) != 0 && i != INT32_MIN) {
        res.setInt32(-i);
    } else {
        double d;
        if (!ToNumber(cx, val, &d))
            return false;
        res.setNumber(-d);
    }

    return true;
}

static MOZ_ALWAYS_INLINE bool
ToIdOperation(JSContext* cx, HandleScript script, jsbytecode* pc, HandleValue idval,
              MutableHandleValue res)
{
    if (idval.isInt32()) {
        res.set(idval);
        return true;
    }

    RootedId id(cx);
    if (!ToPropertyKey(cx, idval, &id))
        return false;

    res.set(IdToValue(id));
    return true;
}

static MOZ_ALWAYS_INLINE bool
GetObjectElementOperation(JSContext* cx, JSOp op, JS::HandleObject obj, JS::HandleObject receiver,
                          HandleValue key, MutableHandleValue res)
{
    MOZ_ASSERT(op == JSOP_GETELEM || op == JSOP_CALLELEM || op == JSOP_GETELEM_SUPER);
    MOZ_ASSERT_IF(op == JSOP_GETELEM || op == JSOP_CALLELEM, obj == receiver);

    do {
        uint32_t index;
        if (IsDefinitelyIndex(key, &index)) {
            if (GetElementNoGC(cx, obj, receiver, index, res.address()))
                break;

            if (!GetElement(cx, obj, receiver, index, res))
                return false;
            break;
        }

        if (key.isString()) {
            JSString* str = key.toString();
            JSAtom* name = str->isAtom() ? &str->asAtom() : AtomizeString(cx, str);
            if (!name)
                return false;
            if (name->isIndex(&index)) {
                if (GetElementNoGC(cx, obj, receiver, index, res.address()))
                    break;
            } else {
                if (GetPropertyNoGC(cx, obj, receiver, name->asPropertyName(), res.address()))
                    break;
            }
        }

        RootedId id(cx);
        if (!ToPropertyKey(cx, key, &id))
            return false;
        if (!GetProperty(cx, obj, receiver, id, res))
            return false;
    } while (false);

    assertSameCompartmentDebugOnly(cx, res);
    return true;
}

static MOZ_ALWAYS_INLINE bool
GetPrimitiveElementOperation(JSContext* cx, JSOp op, JS::HandleValue receiver,
                             HandleValue key, MutableHandleValue res)
{
    MOZ_ASSERT(op == JSOP_GETELEM || op == JSOP_CALLELEM);

    // FIXME: Bug 1234324 We shouldn't be boxing here.
    RootedObject boxed(cx, ToObjectFromStack(cx, receiver));
    if (!boxed)
        return false;

    do {
        uint32_t index;
        if (IsDefinitelyIndex(key, &index)) {
            if (GetElementNoGC(cx, boxed, receiver, index, res.address()))
                break;

            if (!GetElement(cx, boxed, receiver, index, res))
                return false;
            break;
        }

        if (key.isString()) {
            JSString* str = key.toString();
            JSAtom* name = str->isAtom() ? &str->asAtom() : AtomizeString(cx, str);
            if (!name)
                return false;
            if (name->isIndex(&index)) {
                if (GetElementNoGC(cx, boxed, receiver, index, res.address()))
                    break;
            } else {
                if (GetPropertyNoGC(cx, boxed, receiver, name->asPropertyName(), res.address()))
                    break;
            }
        }

        RootedId id(cx);
        if (!ToPropertyKey(cx, key, &id))
            return false;
        if (!GetProperty(cx, boxed, receiver, id, res))
            return false;
    } while (false);

    assertSameCompartmentDebugOnly(cx, res);
    return true;
}

static MOZ_ALWAYS_INLINE bool
GetElemOptimizedArguments(JSContext* cx, AbstractFramePtr frame, MutableHandleValue lref,
                          HandleValue rref, MutableHandleValue res, bool* done)
{
    MOZ_ASSERT(!*done);

    if (IsOptimizedArguments(frame, lref)) {
        if (rref.isInt32()) {
            int32_t i = rref.toInt32();
            if (i >= 0 && uint32_t(i) < frame.numActualArgs()) {
                res.set(frame.unaliasedActual(i));
                *done = true;
                return true;
            }
        }

        RootedScript script(cx, frame.script());
        if (!JSScript::argumentsOptimizationFailed(cx, script))
            return false;

        lref.set(ObjectValue(frame.argsObj()));
    }

    return true;
}

static MOZ_ALWAYS_INLINE bool
GetElementOperation(JSContext* cx, JSOp op, MutableHandleValue lref, HandleValue rref,
                    MutableHandleValue res)
{
    MOZ_ASSERT(op == JSOP_GETELEM || op == JSOP_CALLELEM);

    uint32_t index;
    if (lref.isString() && IsDefinitelyIndex(rref, &index)) {
        JSString* str = lref.toString();
        if (index < str->length()) {
            str = cx->staticStrings().getUnitStringForElement(cx, str, index);
            if (!str)
                return false;
            res.setString(str);
            return true;
        }
    }

    if (lref.isPrimitive()) {
        RootedValue thisv(cx, lref);
        return GetPrimitiveElementOperation(cx, op, thisv, rref, res);
    }

    RootedObject thisv(cx, &lref.toObject());
    return GetObjectElementOperation(cx, op, thisv, thisv, rref, res);
}

static MOZ_ALWAYS_INLINE JSString*
TypeOfOperation(const Value& v, JSRuntime* rt)
{
    JSType type = js::TypeOfValue(v);
    return TypeName(type, *rt->commonNames);
}

static inline JSString*
TypeOfObjectOperation(JSObject* obj, JSRuntime* rt)
{
    JSType type = js::TypeOfObject(obj);
    return TypeName(type, *rt->commonNames);
}

static MOZ_ALWAYS_INLINE bool
InitElemOperation(JSContext* cx, jsbytecode* pc, HandleObject obj, HandleValue idval, HandleValue val)
{
    MOZ_ASSERT(!val.isMagic(JS_ELEMENTS_HOLE));
    MOZ_ASSERT(!obj->getClass()->getGetProperty());
    MOZ_ASSERT(!obj->getClass()->getSetProperty());

    RootedId id(cx);
    if (!ToPropertyKey(cx, idval, &id))
        return false;

    unsigned flags = JSOp(*pc) == JSOP_INITHIDDENELEM ? 0 : JSPROP_ENUMERATE;
    return DefineProperty(cx, obj, id, val, nullptr, nullptr, flags);
}

static MOZ_ALWAYS_INLINE bool
InitArrayElemOperation(JSContext* cx, jsbytecode* pc, HandleObject obj, uint32_t index, HandleValue val)
{
    JSOp op = JSOp(*pc);
    MOZ_ASSERT(op == JSOP_INITELEM_ARRAY || op == JSOP_INITELEM_INC);

    MOZ_ASSERT(obj->is<ArrayObject>() || obj->is<UnboxedArrayObject>());

    if (op == JSOP_INITELEM_INC && index == INT32_MAX) {
        JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_SPREAD_TOO_LARGE);
        return false;
    }

    /*
     * If val is a hole, do not call DefineElement.
     *
     * Furthermore, if the current op is JSOP_INITELEM_INC, always call
     * SetLengthProperty even if it is not the last element initialiser,
     * because it may be followed by JSOP_SPREAD, which will not set the array
     * length if nothing is spread.
     *
     * Alternatively, if the current op is JSOP_INITELEM_ARRAY, the length will
     * have already been set by the earlier JSOP_NEWARRAY; JSOP_INITELEM_ARRAY
     * cannot follow JSOP_SPREAD.
     */
    if (val.isMagic(JS_ELEMENTS_HOLE)) {
        if (op == JSOP_INITELEM_INC) {
            if (!SetLengthProperty(cx, obj, index + 1))
                return false;
        }
    } else {
        if (!DefineElement(cx, obj, index, val, nullptr, nullptr, JSPROP_ENUMERATE))
            return false;
    }

    return true;
}

static MOZ_ALWAYS_INLINE bool
ProcessCallSiteObjOperation(JSContext* cx, RootedObject& cso, RootedObject& raw,
                            RootedValue& rawValue)
{
    bool extensible;
    if (!IsExtensible(cx, cso, &extensible))
        return false;
    if (extensible) {
        JSAtom* name = cx->names().raw;
        if (!DefineProperty(cx, cso, name->asPropertyName(), rawValue, nullptr, nullptr, 0))
            return false;
        if (!FreezeObject(cx, raw))
            return false;
        if (!FreezeObject(cx, cso))
            return false;
    }
    return true;
}

#define RELATIONAL_OP(OP)                                                     \
    JS_BEGIN_MACRO                                                            \
        /* Optimize for two int-tagged operands (typical loop control). */    \
        if (lhs.isInt32() && rhs.isInt32()) {                                 \
            *res = lhs.toInt32() OP rhs.toInt32();                            \
        } else {                                                              \
            if (!ToPrimitive(cx, JSTYPE_NUMBER, lhs))                         \
                return false;                                                 \
            if (!ToPrimitive(cx, JSTYPE_NUMBER, rhs))                         \
                return false;                                                 \
            if (lhs.isString() && rhs.isString()) {                           \
                JSString* l = lhs.toString();                                 \
                JSString* r = rhs.toString();                                 \
                int32_t result;                                               \
                if (!CompareStrings(cx, l, r, &result))                       \
                    return false;                                             \
                *res = result OP 0;                                           \
            } else {                                                          \
                double l, r;                                                  \
                if (!ToNumber(cx, lhs, &l) || !ToNumber(cx, rhs, &r))         \
                    return false;                                             \
                *res = (l OP r);                                              \
            }                                                                 \
        }                                                                     \
        return true;                                                          \
    JS_END_MACRO

static MOZ_ALWAYS_INLINE bool
LessThanOperation(JSContext* cx, MutableHandleValue lhs, MutableHandleValue rhs, bool* res) {
    RELATIONAL_OP(<);
}

static MOZ_ALWAYS_INLINE bool
LessThanOrEqualOperation(JSContext* cx, MutableHandleValue lhs, MutableHandleValue rhs, bool* res) {
    RELATIONAL_OP(<=);
}

static MOZ_ALWAYS_INLINE bool
GreaterThanOperation(JSContext* cx, MutableHandleValue lhs, MutableHandleValue rhs, bool* res) {
    RELATIONAL_OP(>);
}

static MOZ_ALWAYS_INLINE bool
GreaterThanOrEqualOperation(JSContext* cx, MutableHandleValue lhs, MutableHandleValue rhs, bool* res) {
    RELATIONAL_OP(>=);
}

static MOZ_ALWAYS_INLINE bool
BitNot(JSContext* cx, HandleValue in, int* out)
{
    int i;
    if (!ToInt32(cx, in, &i))
        return false;
    *out = ~i;
    return true;
}

static MOZ_ALWAYS_INLINE bool
BitXor(JSContext* cx, HandleValue lhs, HandleValue rhs, int* out)
{
    int left, right;
    if (!ToInt32(cx, lhs, &left) || !ToInt32(cx, rhs, &right))
        return false;
    *out = left ^ right;
    return true;
}

static MOZ_ALWAYS_INLINE bool
BitOr(JSContext* cx, HandleValue lhs, HandleValue rhs, int* out)
{
    int left, right;
    if (!ToInt32(cx, lhs, &left) || !ToInt32(cx, rhs, &right))
        return false;
    *out = left | right;
    return true;
}

static MOZ_ALWAYS_INLINE bool
BitAnd(JSContext* cx, HandleValue lhs, HandleValue rhs, int* out)
{
    int left, right;
    if (!ToInt32(cx, lhs, &left) || !ToInt32(cx, rhs, &right))
        return false;
    *out = left & right;
    return true;
}

static MOZ_ALWAYS_INLINE bool
BitLsh(JSContext* cx, HandleValue lhs, HandleValue rhs, int* out)
{
    int32_t left, right;
    if (!ToInt32(cx, lhs, &left) || !ToInt32(cx, rhs, &right))
        return false;
    *out = uint32_t(left) << (right & 31);
    return true;
}

static MOZ_ALWAYS_INLINE bool
BitRsh(JSContext* cx, HandleValue lhs, HandleValue rhs, int* out)
{
    int32_t left, right;
    if (!ToInt32(cx, lhs, &left) || !ToInt32(cx, rhs, &right))
        return false;
    *out = left >> (right & 31);
    return true;
}

static MOZ_ALWAYS_INLINE bool
UrshOperation(JSContext* cx, HandleValue lhs, HandleValue rhs, MutableHandleValue out)
{
    uint32_t left;
    int32_t  right;
    if (!ToUint32(cx, lhs, &left) || !ToInt32(cx, rhs, &right))
        return false;
    left >>= right & 31;
    out.setNumber(uint32_t(left));
    return true;
}

template <typename T>
static MOZ_ALWAYS_INLINE bool
SignExtendOperation(JSContext* cx, HandleValue in, int* out)
{
    int32_t i;
    if (!ToInt32(cx, in, &i))
        return false;
    *out = (T)i;
    return true;
}

#undef RELATIONAL_OP

inline JSFunction*
ReportIfNotFunction(JSContext* cx, HandleValue v, MaybeConstruct construct = NO_CONSTRUCT)
{
    if (v.isObject() && v.toObject().is<JSFunction>())
        return &v.toObject().as<JSFunction>();

    ReportIsNotFunction(cx, v, -1, construct);
    return nullptr;
}

/*
 * FastCallGuard is used to optimize calls to JS functions from natives written
 * in C++, e.g. Array.prototype.map.  If the callee is not Ion-compiled, this
 * will just call js::Call.  If the callee has a valid IonScript, however, it
 * will enter Ion directly.
 */
class FastCallGuard
{
    InvokeArgs args_;
    RootedFunction fun_;
    RootedScript script_;

    // Constructing a JitContext is pretty expensive due to the TLS access,
    // so only do this if we have to.
    bool useIon_;

  public:
    FastCallGuard(JSContext* cx, const Value& fval)
      : args_(cx)
      , fun_(cx)
      , script_(cx)
      , useIon_(jit::IsIonEnabled(cx))
    {
        initFunction(fval);
    }

    void initFunction(const Value& fval) {
        if (fval.isObject() && fval.toObject().is<JSFunction>()) {
            JSFunction* fun = &fval.toObject().as<JSFunction>();
            if (fun->isInterpreted())
                fun_ = fun;
        }
    }

    InvokeArgs& args() {
        return args_;
    }

    bool call(JSContext* cx, HandleValue callee, HandleValue thisv, MutableHandleValue rval) {
        args_.CallArgs::setCallee(callee);
        args_.CallArgs::setThis(thisv);

        if (useIon_ && fun_) {
            if (!script_) {
                script_ = fun_->getOrCreateScript(cx);
                if (!script_)
                    return false;
            }
            MOZ_ASSERT(fun_->nonLazyScript() == script_);

            jit::MethodStatus status = jit::CanEnterUsingFastInvoke(cx, script_, args_.length());
            if (status == jit::Method_Error)
                return false;
            if (status == jit::Method_Compiled) {
                jit::JitExecStatus result = jit::FastInvoke(cx, fun_, args_);
                if (IsErrorStatus(result))
                    return false;

                MOZ_ASSERT(result == jit::JitExec_Ok);
                rval.set(args_.CallArgs::rval());
                return true;
            }

            MOZ_ASSERT(status == jit::Method_Skipped);

            if (script_->canIonCompile()) {
                // This script is not yet hot. Since calling into Ion is much
                // faster here, bump the warm-up counter a bit to account for this.
                script_->incWarmUpCounter(5);
            }
        }

        if (!InternalCallOrConstruct(cx, args_, NO_CONSTRUCT))
            return false;

        rval.set(args_.CallArgs::rval());
        return true;
    }

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

}  /* namespace js */

#endif /* vm_Interpreter_inl_h */