Pull Basilisk-release forward.

1 files changed, 0 insertions, 1752 deletions

diff --git a/js/src/vm/UnboxedObject.cpp b/js/src/vm/UnboxedObject.cpp
deleted file mode 100644
index d7ad91de4..000000000
--- a/js/src/vm/UnboxedObject.cpp
+++ /dev/null
@@ -1,1752 +0,0 @@
-/* -*- 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/. */
-
-#include "vm/UnboxedObject-inl.h"
-
-#include "jit/BaselineIC.h"
-#include "jit/ExecutableAllocator.h"
-#include "jit/JitCommon.h"
-#include "jit/Linker.h"
-
-#include "jsobjinlines.h"
-
-#include "gc/Nursery-inl.h"
-#include "jit/MacroAssembler-inl.h"
-#include "vm/Shape-inl.h"
-
-using mozilla::ArrayLength;
-using mozilla::DebugOnly;
-using mozilla::PodCopy;
-
-using namespace js;
-
-/////////////////////////////////////////////////////////////////////
-// UnboxedLayout
-/////////////////////////////////////////////////////////////////////
-
-void
-UnboxedLayout::trace(JSTracer* trc)
-{
-    for (size_t i = 0; i < properties_.length(); i++)
-        TraceManuallyBarrieredEdge(trc, &properties_[i].name, "unboxed_layout_name");
-
-    if (newScript())
-        newScript()->trace(trc);
-
-    TraceNullableEdge(trc, &nativeGroup_, "unboxed_layout_nativeGroup");
-    TraceNullableEdge(trc, &nativeShape_, "unboxed_layout_nativeShape");
-    TraceNullableEdge(trc, &allocationScript_, "unboxed_layout_allocationScript");
-    TraceNullableEdge(trc, &replacementGroup_, "unboxed_layout_replacementGroup");
-    TraceNullableEdge(trc, &constructorCode_, "unboxed_layout_constructorCode");
-}
-
-size_t
-UnboxedLayout::sizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf)
-{
-    return mallocSizeOf(this)
-         + properties_.sizeOfExcludingThis(mallocSizeOf)
-         + (newScript() ? newScript()->sizeOfIncludingThis(mallocSizeOf) : 0)
-         + mallocSizeOf(traceList());
-}
-
-void
-UnboxedLayout::setNewScript(TypeNewScript* newScript, bool writeBarrier /* = true */)
-{
-    if (newScript_ && writeBarrier)
-        TypeNewScript::writeBarrierPre(newScript_);
-    newScript_ = newScript;
-}
-
-// Constructor code returns a 0x1 value to indicate the constructor code should
-// be cleared.
-static const uintptr_t CLEAR_CONSTRUCTOR_CODE_TOKEN = 0x1;
-
-/* static */ bool
-UnboxedLayout::makeConstructorCode(JSContext* cx, HandleObjectGroup group)
-{
-    gc::AutoSuppressGC suppress(cx);
-
-    using namespace jit;
-
-    if (!cx->compartment()->ensureJitCompartmentExists(cx))
-        return false;
-
-    UnboxedLayout& layout = group->unboxedLayout();
-    MOZ_ASSERT(!layout.constructorCode());
-
-    UnboxedPlainObject* templateObject = UnboxedPlainObject::create(cx, group, TenuredObject);
-    if (!templateObject)
-        return false;
-
-    JitContext jitContext(cx, nullptr);
-
-    MacroAssembler masm;
-
-    Register propertiesReg, newKindReg;
-#ifdef JS_CODEGEN_X86
-    propertiesReg = eax;
-    newKindReg = ecx;
-    masm.loadPtr(Address(masm.getStackPointer(), sizeof(void*)), propertiesReg);
-    masm.loadPtr(Address(masm.getStackPointer(), 2 * sizeof(void*)), newKindReg);
-#else
-    propertiesReg = IntArgReg0;
-    newKindReg = IntArgReg1;
-#endif
-
-#ifdef JS_CODEGEN_ARM64
-    // ARM64 communicates stack address via sp, but uses a pseudo-sp for addressing.
-    masm.initStackPtr();
-#endif
-
-    MOZ_ASSERT(propertiesReg.volatile_());
-    MOZ_ASSERT(newKindReg.volatile_());
-
-    AllocatableGeneralRegisterSet regs(GeneralRegisterSet::All());
-    regs.take(propertiesReg);
-    regs.take(newKindReg);
-    Register object = regs.takeAny(), scratch1 = regs.takeAny(), scratch2 = regs.takeAny();
-
-    LiveGeneralRegisterSet savedNonVolatileRegisters = SavedNonVolatileRegisters(regs);
-    masm.PushRegsInMask(savedNonVolatileRegisters);
-
-    // The scratch double register might be used by MacroAssembler methods.
-    if (ScratchDoubleReg.volatile_())
-        masm.push(ScratchDoubleReg);
-
-    Label failure, tenuredObject, allocated;
-    masm.branch32(Assembler::NotEqual, newKindReg, Imm32(GenericObject), &tenuredObject);
-    masm.branchTest32(Assembler::NonZero, AbsoluteAddress(group->addressOfFlags()),
-                      Imm32(OBJECT_FLAG_PRE_TENURE), &tenuredObject);
-
-    // Allocate an object in the nursery
-    masm.createGCObject(object, scratch1, templateObject, gc::DefaultHeap, &failure,
-                        /* initFixedSlots = */ false);
-
-    masm.jump(&allocated);
-    masm.bind(&tenuredObject);
-
-    // Allocate an object in the tenured heap.
-    masm.createGCObject(object, scratch1, templateObject, gc::TenuredHeap, &failure,
-                        /* initFixedSlots = */ false);
-
-    // If any of the properties being stored are in the nursery, add a store
-    // buffer entry for the new object.
-    Label postBarrier;
-    for (size_t i = 0; i < layout.properties().length(); i++) {
-        const UnboxedLayout::Property& property = layout.properties()[i];
-        if (property.type == JSVAL_TYPE_OBJECT) {
-            Address valueAddress(propertiesReg, i * sizeof(IdValuePair) + offsetof(IdValuePair, value));
-            Label notObject;
-            masm.branchTestObject(Assembler::NotEqual, valueAddress, &notObject);
-            Register valueObject = masm.extractObject(valueAddress, scratch1);
-            masm.branchPtrInNurseryChunk(Assembler::Equal, valueObject, scratch2, &postBarrier);
-            masm.bind(&notObject);
-        }
-    }
-
-    masm.jump(&allocated);
-    masm.bind(&postBarrier);
-
-    LiveGeneralRegisterSet liveVolatileRegisters;
-    liveVolatileRegisters.add(propertiesReg);
-    if (object.volatile_())
-        liveVolatileRegisters.add(object);
-    masm.PushRegsInMask(liveVolatileRegisters);
-
-    masm.mov(ImmPtr(cx->runtime()), scratch1);
-    masm.setupUnalignedABICall(scratch2);
-    masm.passABIArg(scratch1);
-    masm.passABIArg(object);
-    masm.callWithABI(JS_FUNC_TO_DATA_PTR(void*, PostWriteBarrier));
-
-    masm.PopRegsInMask(liveVolatileRegisters);
-
-    masm.bind(&allocated);
-
-    ValueOperand valueOperand;
-#ifdef JS_NUNBOX32
-    valueOperand = ValueOperand(scratch1, scratch2);
-#else
-    valueOperand = ValueOperand(scratch1);
-#endif
-
-    Label failureStoreOther, failureStoreObject;
-
-    for (size_t i = 0; i < layout.properties().length(); i++) {
-        const UnboxedLayout::Property& property = layout.properties()[i];
-        Address valueAddress(propertiesReg, i * sizeof(IdValuePair) + offsetof(IdValuePair, value));
-        Address targetAddress(object, UnboxedPlainObject::offsetOfData() + property.offset);
-
-        masm.loadValue(valueAddress, valueOperand);
-
-        if (property.type == JSVAL_TYPE_OBJECT) {
-            HeapTypeSet* types = group->maybeGetProperty(IdToTypeId(NameToId(property.name)));
-
-            Label notObject;
-            masm.branchTestObject(Assembler::NotEqual, valueOperand,
-                                  types->mightBeMIRType(MIRType::Null) ? &notObject : &failureStoreObject);
-
-            Register payloadReg = masm.extractObject(valueOperand, scratch1);
-
-            if (!types->hasType(TypeSet::AnyObjectType())) {
-                Register scratch = (payloadReg == scratch1) ? scratch2 : scratch1;
-                masm.guardObjectType(payloadReg, types, scratch, &failureStoreObject);
-            }
-
-            masm.storeUnboxedProperty(targetAddress, JSVAL_TYPE_OBJECT,
-                                      TypedOrValueRegister(MIRType::Object,
-                                                           AnyRegister(payloadReg)), nullptr);
-
-            if (notObject.used()) {
-                Label done;
-                masm.jump(&done);
-                masm.bind(&notObject);
-                masm.branchTestNull(Assembler::NotEqual, valueOperand, &failureStoreOther);
-                masm.storeUnboxedProperty(targetAddress, JSVAL_TYPE_OBJECT, NullValue(), nullptr);
-                masm.bind(&done);
-            }
-        } else {
-            masm.storeUnboxedProperty(targetAddress, property.type,
-                                      ConstantOrRegister(valueOperand), &failureStoreOther);
-        }
-    }
-
-    Label done;
-    masm.bind(&done);
-
-    if (object != ReturnReg)
-        masm.movePtr(object, ReturnReg);
-
-    // Restore non-volatile registers which were saved on entry.
-    if (ScratchDoubleReg.volatile_())
-        masm.pop(ScratchDoubleReg);
-    masm.PopRegsInMask(savedNonVolatileRegisters);
-
-    masm.abiret();
-
-    masm.bind(&failureStoreOther);
-
-    // There was a failure while storing a value which cannot be stored at all
-    // in the unboxed object. Initialize the object so it is safe for GC and
-    // return null.
-    masm.initUnboxedObjectContents(object, templateObject);
-
-    masm.bind(&failure);
-
-    masm.movePtr(ImmWord(0), object);
-    masm.jump(&done);
-
-    masm.bind(&failureStoreObject);
-
-    // There was a failure while storing a value to an object slot of the
-    // unboxed object. If the value is storable, the failure occurred due to
-    // incomplete type information in the object, so return a token to trigger
-    // regeneration of the jitcode after a new object is created in the VM.
-    {
-        Label isObject;
-        masm.branchTestObject(Assembler::Equal, valueOperand, &isObject);
-        masm.branchTestNull(Assembler::NotEqual, valueOperand, &failureStoreOther);
-        masm.bind(&isObject);
-    }
-
-    // Initialize the object so it is safe for GC.
-    masm.initUnboxedObjectContents(object, templateObject);
-
-    masm.movePtr(ImmWord(CLEAR_CONSTRUCTOR_CODE_TOKEN), object);
-    masm.jump(&done);
-
-    Linker linker(masm);
-    AutoFlushICache afc("UnboxedObject");
-    JitCode* code = linker.newCode<NoGC>(cx, OTHER_CODE);
-    if (!code)
-        return false;
-
-    layout.setConstructorCode(code);
-    return true;
-}
-
-void
-UnboxedLayout::detachFromCompartment()
-{
-    if (isInList())
-        remove();
-}
-
-/////////////////////////////////////////////////////////////////////
-// UnboxedPlainObject
-/////////////////////////////////////////////////////////////////////
-
-bool
-UnboxedPlainObject::setValue(ExclusiveContext* cx, const UnboxedLayout::Property& property,
-                             const Value& v)
-{
-    uint8_t* p = &data_[property.offset];
-    return SetUnboxedValue(cx, this, NameToId(property.name), p, property.type, v,
-                           /* preBarrier = */ true);
-}
-
-Value
-UnboxedPlainObject::getValue(const UnboxedLayout::Property& property,
-                             bool maybeUninitialized /* = false */)
-{
-    uint8_t* p = &data_[property.offset];
-    return GetUnboxedValue(p, property.type, maybeUninitialized);
-}
-
-void
-UnboxedPlainObject::trace(JSTracer* trc, JSObject* obj)
-{
-    if (obj->as<UnboxedPlainObject>().expando_) {
-        TraceManuallyBarrieredEdge(trc,
-            reinterpret_cast<NativeObject**>(&obj->as<UnboxedPlainObject>().expando_),
-            "unboxed_expando");
-    }
-
-    const UnboxedLayout& layout = obj->as<UnboxedPlainObject>().layoutDontCheckGeneration();
-    const int32_t* list = layout.traceList();
-    if (!list)
-        return;
-
-    uint8_t* data = obj->as<UnboxedPlainObject>().data();
-    while (*list != -1) {
-        GCPtrString* heap = reinterpret_cast<GCPtrString*>(data + *list);
-        TraceEdge(trc, heap, "unboxed_string");
-        list++;
-    }
-    list++;
-    while (*list != -1) {
-        GCPtrObject* heap = reinterpret_cast<GCPtrObject*>(data + *list);
-        TraceNullableEdge(trc, heap, "unboxed_object");
-        list++;
-    }
-
-    // Unboxed objects don't have Values to trace.
-    MOZ_ASSERT(*(list + 1) == -1);
-}
-
-/* static */ UnboxedExpandoObject*
-UnboxedPlainObject::ensureExpando(JSContext* cx, Handle<UnboxedPlainObject*> obj)
-{
-    if (obj->expando_)
-        return obj->expando_;
-
-    UnboxedExpandoObject* expando =
-        NewObjectWithGivenProto<UnboxedExpandoObject>(cx, nullptr, gc::AllocKind::OBJECT4);
-    if (!expando)
-        return nullptr;
-
-    // Don't track property types for expando objects. This allows Baseline
-    // and Ion AddSlot ICs to guard on the unboxed group without guarding on
-    // the expando group.
-    MarkObjectGroupUnknownProperties(cx, expando->group());
-
-    // If the expando is tenured then the original object must also be tenured.
-    // Otherwise barriers triggered on the original object for writes to the
-    // expando (as can happen in the JIT) won't see the tenured->nursery edge.
-    // See WholeCellEdges::mark.
-    MOZ_ASSERT_IF(!IsInsideNursery(expando), !IsInsideNursery(obj));
-
-    // As with setValue(), we need to manually trigger post barriers on the
-    // whole object. If we treat the field as a GCPtrObject and later
-    // convert the object to its native representation, we will end up with a
-    // corrupted store buffer entry.
-    if (IsInsideNursery(expando) && !IsInsideNursery(obj))
-        cx->runtime()->gc.storeBuffer.putWholeCell(obj);
-
-    obj->expando_ = expando;
-    return expando;
-}
-
-bool
-UnboxedPlainObject::containsUnboxedOrExpandoProperty(ExclusiveContext* cx, jsid id) const
-{
-    if (layout().lookup(id))
-        return true;
-
-    if (maybeExpando() && maybeExpando()->containsShapeOrElement(cx, id))
-        return true;
-
-    return false;
-}
-
-static bool
-PropagatePropertyTypes(JSContext* cx, jsid id, ObjectGroup* oldGroup, ObjectGroup* newGroup)
-{
-    HeapTypeSet* typeProperty = oldGroup->maybeGetProperty(id);
-    TypeSet::TypeList types;
-    if (!typeProperty->enumerateTypes(&types)) {
-        ReportOutOfMemory(cx);
-        return false;
-    }
-    for (size_t j = 0; j < types.length(); j++)
-        AddTypePropertyId(cx, newGroup, nullptr, id, types[j]);
-    return true;
-}
-
-static PlainObject*
-MakeReplacementTemplateObject(JSContext* cx, HandleObjectGroup group, const UnboxedLayout &layout)
-{
-    PlainObject* obj = NewObjectWithGroup<PlainObject>(cx, group, layout.getAllocKind(),
-                                                       TenuredObject);
-    if (!obj)
-        return nullptr;
-
-    for (size_t i = 0; i < layout.properties().length(); i++) {
-        const UnboxedLayout::Property& property = layout.properties()[i];
-        if (!obj->addDataProperty(cx, NameToId(property.name), i, JSPROP_ENUMERATE))
-            return nullptr;
-        MOZ_ASSERT(obj->slotSpan() == i + 1);
-        MOZ_ASSERT(!obj->inDictionaryMode());
-    }
-
-    return obj;
-}
-
-/* static */ bool
-UnboxedLayout::makeNativeGroup(JSContext* cx, ObjectGroup* group)
-{
-    AutoEnterAnalysis enter(cx);
-
-    UnboxedLayout& layout = group->unboxedLayout();
-    Rooted<TaggedProto> proto(cx, group->proto());
-
-    MOZ_ASSERT(!layout.nativeGroup());
-
-    RootedObjectGroup replacementGroup(cx);
-
-    const Class* clasp = layout.isArray() ? &ArrayObject::class_ : &PlainObject::class_;
-
-    // Immediately clear any new script on the group. This is done by replacing
-    // the existing new script with one for a replacement default new group.
-    // This is done so that the size of the replacment group's objects is the
-    // same as that for the unboxed group, so that we do not see polymorphic
-    // slot accesses later on for sites that see converted objects from this
-    // group and objects that were allocated using the replacement new group.
-    if (layout.newScript()) {
-        MOZ_ASSERT(!layout.isArray());
-
-        replacementGroup = ObjectGroupCompartment::makeGroup(cx, &PlainObject::class_, proto);
-        if (!replacementGroup)
-            return false;
-
-        PlainObject* templateObject = MakeReplacementTemplateObject(cx, replacementGroup, layout);
-        if (!templateObject)
-            return false;
-
-        TypeNewScript* replacementNewScript =
-            TypeNewScript::makeNativeVersion(cx, layout.newScript(), templateObject);
-        if (!replacementNewScript)
-            return false;
-
-        replacementGroup->setNewScript(replacementNewScript);
-        gc::TraceTypeNewScript(replacementGroup);
-
-        group->clearNewScript(cx, replacementGroup);
-    }
-
-    // Similarly, if this group is keyed to an allocation site, replace its
-    // entry with a new group that has no unboxed layout.
-    if (layout.allocationScript()) {
-        RootedScript script(cx, layout.allocationScript());
-        jsbytecode* pc = layout.allocationPc();
-
-        replacementGroup = ObjectGroupCompartment::makeGroup(cx, clasp, proto);
-        if (!replacementGroup)
-            return false;
-
-        PlainObject* templateObject = &script->getObject(pc)->as<PlainObject>();
-        replacementGroup->addDefiniteProperties(cx, templateObject->lastProperty());
-
-        JSProtoKey key = layout.isArray() ? JSProto_Array : JSProto_Object;
-        cx->compartment()->objectGroups.replaceAllocationSiteGroup(script, pc, key,
-                                                                   replacementGroup);
-
-        // Clear any baseline information at this opcode which might use the old group.
-        if (script->hasBaselineScript()) {
-            jit::ICEntry& entry = script->baselineScript()->icEntryFromPCOffset(script->pcToOffset(pc));
-            jit::ICFallbackStub* fallback = entry.fallbackStub();
-            for (jit::ICStubIterator iter = fallback->beginChain(); !iter.atEnd(); iter++)
-                iter.unlink(cx);
-            if (fallback->isNewObject_Fallback())
-                fallback->toNewObject_Fallback()->setTemplateObject(nullptr);
-            else if (fallback->isNewArray_Fallback())
-                fallback->toNewArray_Fallback()->setTemplateGroup(replacementGroup);
-        }
-    }
-
-    size_t nfixed = layout.isArray() ? 0 : gc::GetGCKindSlots(layout.getAllocKind());
-
-    if (layout.isArray()) {
-        // The length shape to use for arrays is cached via a modified initial
-        // shape for array objects. Create an array now to make sure this entry
-        // is instantiated.
-        if (!NewDenseEmptyArray(cx))
-            return false;
-    }
-
-    RootedShape shape(cx, EmptyShape::getInitialShape(cx, clasp, proto, nfixed, 0));
-    if (!shape)
-        return false;
-
-    MOZ_ASSERT_IF(layout.isArray(), !shape->isEmptyShape() && shape->slotSpan() == 0);
-
-    // Add shapes for each property, if this is for a plain object.
-    for (size_t i = 0; i < layout.properties().length(); i++) {
-        const UnboxedLayout::Property& property = layout.properties()[i];
-
-        Rooted<StackShape> child(cx, StackShape(shape->base()->unowned(), NameToId(property.name),
-                                                i, JSPROP_ENUMERATE, 0));
-        shape = cx->zone()->propertyTree.getChild(cx, shape, child);
-        if (!shape)
-            return false;
-    }
-
-    ObjectGroup* nativeGroup =
-        ObjectGroupCompartment::makeGroup(cx, clasp, proto,
-                                          group->flags() & OBJECT_FLAG_DYNAMIC_MASK);
-    if (!nativeGroup)
-        return false;
-
-    // No sense propagating if we don't know what we started with.
-    if (!group->unknownProperties()) {
-        // Propagate all property types from the old group to the new group.
-        if (layout.isArray()) {
-            if (!PropagatePropertyTypes(cx, JSID_VOID, group, nativeGroup))
-                return false;
-        } else {
-            for (size_t i = 0; i < layout.properties().length(); i++) {
-                const UnboxedLayout::Property& property = layout.properties()[i];
-                jsid id = NameToId(property.name);
-                if (!PropagatePropertyTypes(cx, id, group, nativeGroup))
-                    return false;
-
-                // If we are OOM we may not be able to propagate properties.
-                if (nativeGroup->unknownProperties())
-                    break;
-
-                HeapTypeSet* nativeProperty = nativeGroup->maybeGetProperty(id);
-                if (nativeProperty && nativeProperty->canSetDefinite(i))
-                    nativeProperty->setDefinite(i);
-            }
-        }
-    } else {
-        // If we skip, though, the new group had better agree.
-        MOZ_ASSERT(nativeGroup->unknownProperties());
-    }
-
-    layout.nativeGroup_ = nativeGroup;
-    layout.nativeShape_ = shape;
-    layout.replacementGroup_ = replacementGroup;
-
-    nativeGroup->setOriginalUnboxedGroup(group);
-
-    group->markStateChange(cx);
-
-    return true;
-}
-
-/* static */ bool
-UnboxedPlainObject::convertToNative(JSContext* cx, JSObject* obj)
-{
-    const UnboxedLayout& layout = obj->as<UnboxedPlainObject>().layout();
-    UnboxedExpandoObject* expando = obj->as<UnboxedPlainObject>().maybeExpando();
-
-    if (!layout.nativeGroup()) {
-        if (!UnboxedLayout::makeNativeGroup(cx, obj->group()))
-            return false;
-
-        // makeNativeGroup can reentrantly invoke this method.
-        if (obj->is<PlainObject>())
-            return true;
-    }
-
-    AutoValueVector values(cx);
-    for (size_t i = 0; i < layout.properties().length(); i++) {
-        // We might be reading properties off the object which have not been
-        // initialized yet. Make sure any double values we read here are
-        // canonicalized.
-        if (!values.append(obj->as<UnboxedPlainObject>().getValue(layout.properties()[i], true)))
-            return false;
-    }
-
-    // We are eliminating the expando edge with the conversion, so trigger a
-    // pre barrier.
-    JSObject::writeBarrierPre(expando);
-
-    // Additionally trigger a post barrier on the expando itself. Whole cell
-    // store buffer entries can be added on the original unboxed object for
-    // writes to the expando (see WholeCellEdges::trace), so after conversion
-    // we need to make sure the expando itself will still be traced.
-    if (expando && !IsInsideNursery(expando))
-        cx->runtime()->gc.storeBuffer.putWholeCell(expando);
-
-    obj->setGroup(layout.nativeGroup());
-    obj->as<PlainObject>().setLastPropertyMakeNative(cx, layout.nativeShape());
-
-    for (size_t i = 0; i < values.length(); i++)
-        obj->as<PlainObject>().initSlotUnchecked(i, values[i]);
-
-    if (expando) {
-        // Add properties from the expando object to the object, in order.
-        // Suppress GC here, so that callers don't need to worry about this
-        // method collecting. The stuff below can only fail due to OOM, in
-        // which case the object will not have been completely filled back in.
-        gc::AutoSuppressGC suppress(cx);
-
-        Vector<jsid> ids(cx);
-        for (Shape::Range<NoGC> r(expando->lastProperty()); !r.empty(); r.popFront()) {
-            if (!ids.append(r.front().propid()))
-                return false;
-        }
-        for (size_t i = 0; i < expando->getDenseInitializedLength(); i++) {
-            if (!expando->getDenseElement(i).isMagic(JS_ELEMENTS_HOLE)) {
-                if (!ids.append(INT_TO_JSID(i)))
-                    return false;
-            }
-        }
-        ::Reverse(ids.begin(), ids.end());
-
-        RootedPlainObject nobj(cx, &obj->as<PlainObject>());
-        Rooted<UnboxedExpandoObject*> nexpando(cx, expando);
-        RootedId id(cx);
-        Rooted<PropertyDescriptor> desc(cx);
-        for (size_t i = 0; i < ids.length(); i++) {
-            id = ids[i];
-            if (!GetOwnPropertyDescriptor(cx, nexpando, id, &desc))
-                return false;
-            ObjectOpResult result;
-            if (!DefineProperty(cx, nobj, id, desc, result))
-                return false;
-            MOZ_ASSERT(result.ok());
-        }
-    }
-
-    return true;
-}
-
-/* static */
-UnboxedPlainObject*
-UnboxedPlainObject::create(ExclusiveContext* cx, HandleObjectGroup group, NewObjectKind newKind)
-{
-    AutoSetNewObjectMetadata metadata(cx);
-
-    MOZ_ASSERT(group->clasp() == &class_);
-    gc::AllocKind allocKind = group->unboxedLayout().getAllocKind();
-
-    UnboxedPlainObject* res =
-        NewObjectWithGroup<UnboxedPlainObject>(cx, group, allocKind, newKind);
-    if (!res)
-        return nullptr;
-
-    // Overwrite the dummy shape which was written to the object's expando field.
-    res->initExpando();
-
-    // Initialize reference fields of the object. All fields in the object will
-    // be overwritten shortly, but references need to be safe for the GC.
-    const int32_t* list = res->layout().traceList();
-    if (list) {
-        uint8_t* data = res->data();
-        while (*list != -1) {
-            GCPtrString* heap = reinterpret_cast<GCPtrString*>(data + *list);
-            heap->init(cx->names().empty);
-            list++;
-        }
-        list++;
-        while (*list != -1) {
-            GCPtrObject* heap = reinterpret_cast<GCPtrObject*>(data + *list);
-            heap->init(nullptr);
-            list++;
-        }
-        // Unboxed objects don't have Values to initialize.
-        MOZ_ASSERT(*(list + 1) == -1);
-    }
-
-    return res;
-}
-
-/* static */ JSObject*
-UnboxedPlainObject::createWithProperties(ExclusiveContext* cx, HandleObjectGroup group,
-                                         NewObjectKind newKind, IdValuePair* properties)
-{
-    MOZ_ASSERT(newKind == GenericObject || newKind == TenuredObject);
-
-    UnboxedLayout& layout = group->unboxedLayout();
-
-    if (layout.constructorCode()) {
-        MOZ_ASSERT(cx->isJSContext());
-
-        typedef JSObject* (*ConstructorCodeSignature)(IdValuePair*, NewObjectKind);
-        ConstructorCodeSignature function =
-            reinterpret_cast<ConstructorCodeSignature>(layout.constructorCode()->raw());
-
-        JSObject* obj;
-        {
-            JS::AutoSuppressGCAnalysis nogc;
-            obj = reinterpret_cast<JSObject*>(CALL_GENERATED_2(function, properties, newKind));
-        }
-        if (obj > reinterpret_cast<JSObject*>(CLEAR_CONSTRUCTOR_CODE_TOKEN))
-            return obj;
-
-        if (obj == reinterpret_cast<JSObject*>(CLEAR_CONSTRUCTOR_CODE_TOKEN))
-            layout.setConstructorCode(nullptr);
-    }
-
-    UnboxedPlainObject* obj = UnboxedPlainObject::create(cx, group, newKind);
-    if (!obj)
-        return nullptr;
-
-    for (size_t i = 0; i < layout.properties().length(); i++) {
-        if (!obj->setValue(cx, layout.properties()[i], properties[i].value))
-            return NewPlainObjectWithProperties(cx, properties, layout.properties().length(), newKind);
-    }
-
-#ifndef JS_CODEGEN_NONE
-    if (cx->isJSContext() &&
-        !group->unknownProperties() &&
-        !layout.constructorCode() &&
-        cx->asJSContext()->runtime()->jitSupportsFloatingPoint &&
-        jit::CanLikelyAllocateMoreExecutableMemory())
-    {
-        if (!UnboxedLayout::makeConstructorCode(cx->asJSContext(), group))
-            return nullptr;
-    }
-#endif
-
-    return obj;
-}
-
-/* static */ bool
-UnboxedPlainObject::obj_lookupProperty(JSContext* cx, HandleObject obj,
-                                       HandleId id, MutableHandleObject objp,
-                                       MutableHandleShape propp)
-{
-    if (obj->as<UnboxedPlainObject>().containsUnboxedOrExpandoProperty(cx, id)) {
-        MarkNonNativePropertyFound<CanGC>(propp);
-        objp.set(obj);
-        return true;
-    }
-
-    RootedObject proto(cx, obj->staticPrototype());
-    if (!proto) {
-        objp.set(nullptr);
-        propp.set(nullptr);
-        return true;
-    }
-
-    return LookupProperty(cx, proto, id, objp, propp);
-}
-
-/* static */ bool
-UnboxedPlainObject::obj_defineProperty(JSContext* cx, HandleObject obj, HandleId id,
-                                       Handle<PropertyDescriptor> desc,
-                                       ObjectOpResult& result)
-{
-    const UnboxedLayout& layout = obj->as<UnboxedPlainObject>().layout();
-
-    if (const UnboxedLayout::Property* property = layout.lookup(id)) {
-        if (!desc.getter() && !desc.setter() && desc.attributes() == JSPROP_ENUMERATE) {
-            // This define is equivalent to setting an existing property.
-            if (obj->as<UnboxedPlainObject>().setValue(cx, *property, desc.value()))
-                return result.succeed();
-        }
-
-        // Trying to incompatibly redefine an existing property requires the
-        // object to be converted to a native object.
-        if (!convertToNative(cx, obj))
-            return false;
-
-        return DefineProperty(cx, obj, id, desc, result);
-    }
-
-    // Define the property on the expando object.
-    Rooted<UnboxedExpandoObject*> expando(cx, ensureExpando(cx, obj.as<UnboxedPlainObject>()));
-    if (!expando)
-        return false;
-
-    // Update property types on the unboxed object as well.
-    AddTypePropertyId(cx, obj, id, desc.value());
-
-    return DefineProperty(cx, expando, id, desc, result);
-}
-
-/* static */ bool
-UnboxedPlainObject::obj_hasProperty(JSContext* cx, HandleObject obj, HandleId id, bool* foundp)
-{
-    if (obj->as<UnboxedPlainObject>().containsUnboxedOrExpandoProperty(cx, id)) {
-        *foundp = true;
-        return true;
-    }
-
-    RootedObject proto(cx, obj->staticPrototype());
-    if (!proto) {
-        *foundp = false;
-        return true;
-    }
-
-    return HasProperty(cx, proto, id, foundp);
-}
-
-/* static */ bool
-UnboxedPlainObject::obj_getProperty(JSContext* cx, HandleObject obj, HandleValue receiver,
-                                    HandleId id, MutableHandleValue vp)
-{
-    const UnboxedLayout& layout = obj->as<UnboxedPlainObject>().layout();
-
-    if (const UnboxedLayout::Property* property = layout.lookup(id)) {
-        vp.set(obj->as<UnboxedPlainObject>().getValue(*property));
-        return true;
-    }
-
-    if (UnboxedExpandoObject* expando = obj->as<UnboxedPlainObject>().maybeExpando()) {
-        if (expando->containsShapeOrElement(cx, id)) {
-            RootedObject nexpando(cx, expando);
-            return GetProperty(cx, nexpando, receiver, id, vp);
-        }
-    }
-
-    RootedObject proto(cx, obj->staticPrototype());
-    if (!proto) {
-        vp.setUndefined();
-        return true;
-    }
-
-    return GetProperty(cx, proto, receiver, id, vp);
-}
-
-/* static */ bool
-UnboxedPlainObject::obj_setProperty(JSContext* cx, HandleObject obj, HandleId id, HandleValue v,
-                                    HandleValue receiver, ObjectOpResult& result)
-{
-    const UnboxedLayout& layout = obj->as<UnboxedPlainObject>().layout();
-
-    if (const UnboxedLayout::Property* property = layout.lookup(id)) {
-        if (receiver.isObject() && obj == &receiver.toObject()) {
-            if (obj->as<UnboxedPlainObject>().setValue(cx, *property, v))
-                return result.succeed();
-
-            if (!convertToNative(cx, obj))
-                return false;
-            return SetProperty(cx, obj, id, v, receiver, result);
-        }
-
-        return SetPropertyByDefining(cx, id, v, receiver, result);
-    }
-
-    if (UnboxedExpandoObject* expando = obj->as<UnboxedPlainObject>().maybeExpando()) {
-        if (expando->containsShapeOrElement(cx, id)) {
-            // Update property types on the unboxed object as well.
-            AddTypePropertyId(cx, obj, id, v);
-
-            RootedObject nexpando(cx, expando);
-            return SetProperty(cx, nexpando, id, v, receiver, result);
-        }
-    }
-
-    return SetPropertyOnProto(cx, obj, id, v, receiver, result);
-}
-
-/* static */ bool
-UnboxedPlainObject::obj_getOwnPropertyDescriptor(JSContext* cx, HandleObject obj, HandleId id,
-                                                 MutableHandle<PropertyDescriptor> desc)
-{
-    const UnboxedLayout& layout = obj->as<UnboxedPlainObject>().layout();
-
-    if (const UnboxedLayout::Property* property = layout.lookup(id)) {
-        desc.value().set(obj->as<UnboxedPlainObject>().getValue(*property));
-        desc.setAttributes(JSPROP_ENUMERATE);
-        desc.object().set(obj);
-        return true;
-    }
-
-    if (UnboxedExpandoObject* expando = obj->as<UnboxedPlainObject>().maybeExpando()) {
-        if (expando->containsShapeOrElement(cx, id)) {
-            RootedObject nexpando(cx, expando);
-            if (!GetOwnPropertyDescriptor(cx, nexpando, id, desc))
-                return false;
-            if (desc.object() == nexpando)
-                desc.object().set(obj);
-            return true;
-        }
-    }
-
-    desc.object().set(nullptr);
-    return true;
-}
-
-/* static */ bool
-UnboxedPlainObject::obj_deleteProperty(JSContext* cx, HandleObject obj, HandleId id,
-                                       ObjectOpResult& result)
-{
-    if (!convertToNative(cx, obj))
-        return false;
-    return DeleteProperty(cx, obj, id, result);
-}
-
-/* static */ bool
-UnboxedPlainObject::obj_watch(JSContext* cx, HandleObject obj, HandleId id, HandleObject callable)
-{
-    if (!convertToNative(cx, obj))
-        return false;
-    return WatchProperty(cx, obj, id, callable);
-}
-
-/* static */ bool
-UnboxedPlainObject::obj_enumerate(JSContext* cx, HandleObject obj, AutoIdVector& properties,
-                                  bool enumerableOnly)
-{
-    // Ignore expando properties here, they are special-cased by the property
-    // enumeration code.
-
-    const UnboxedLayout::PropertyVector& unboxed = obj->as<UnboxedPlainObject>().layout().properties();
-    for (size_t i = 0; i < unboxed.length(); i++) {
-        if (!properties.append(NameToId(unboxed[i].name)))
-            return false;
-    }
-
-    return true;
-}
-
-const Class UnboxedExpandoObject::class_ = {
-    "UnboxedExpandoObject",
-    0
-};
-
-static const ClassOps UnboxedPlainObjectClassOps = {
-    nullptr,        /* addProperty */
-    nullptr,        /* delProperty */
-    nullptr,        /* getProperty */
-    nullptr,        /* setProperty */
-    nullptr,        /* enumerate   */
-    nullptr,        /* resolve     */
-    nullptr,        /* mayResolve  */
-    nullptr,        /* finalize    */
-    nullptr,        /* call        */
-    nullptr,        /* hasInstance */
-    nullptr,        /* construct   */
-    UnboxedPlainObject::trace,
-};
-
-static const ObjectOps UnboxedPlainObjectObjectOps = {
-    UnboxedPlainObject::obj_lookupProperty,
-    UnboxedPlainObject::obj_defineProperty,
-    UnboxedPlainObject::obj_hasProperty,
-    UnboxedPlainObject::obj_getProperty,
-    UnboxedPlainObject::obj_setProperty,
-    UnboxedPlainObject::obj_getOwnPropertyDescriptor,
-    UnboxedPlainObject::obj_deleteProperty,
-    UnboxedPlainObject::obj_watch,
-    nullptr,   /* No unwatch needed, as watch() converts the object to native */
-    nullptr,   /* getElements */
-    UnboxedPlainObject::obj_enumerate,
-    nullptr    /* funToString */
-};
-
-const Class UnboxedPlainObject::class_ = {
-    js_Object_str,
-    Class::NON_NATIVE |
-    JSCLASS_HAS_CACHED_PROTO(JSProto_Object) |
-    JSCLASS_DELAY_METADATA_BUILDER,
-    &UnboxedPlainObjectClassOps,
-    JS_NULL_CLASS_SPEC,
-    JS_NULL_CLASS_EXT,
-    &UnboxedPlainObjectObjectOps
-};
-
-/////////////////////////////////////////////////////////////////////
-// UnboxedArrayObject
-/////////////////////////////////////////////////////////////////////
-
-template <JSValueType Type>
-DenseElementResult
-AppendUnboxedDenseElements(UnboxedArrayObject* obj, uint32_t initlen,
-                           MutableHandle<GCVector<Value>> values)
-{
-    for (size_t i = 0; i < initlen; i++)
-        values.infallibleAppend(obj->getElementSpecific<Type>(i));
-    return DenseElementResult::Success;
-}
-
-DefineBoxedOrUnboxedFunctor3(AppendUnboxedDenseElements,
-                             UnboxedArrayObject*, uint32_t, MutableHandle<GCVector<Value>>);
-
-/* static */ bool
-UnboxedArrayObject::convertToNativeWithGroup(ExclusiveContext* cx, JSObject* obj,
-                                             ObjectGroup* group, Shape* shape)
-{
-    size_t length = obj->as<UnboxedArrayObject>().length();
-    size_t initlen = obj->as<UnboxedArrayObject>().initializedLength();
-
-    Rooted<GCVector<Value>> values(cx, GCVector<Value>(cx));
-    if (!values.reserve(initlen))
-        return false;
-
-    AppendUnboxedDenseElementsFunctor functor(&obj->as<UnboxedArrayObject>(), initlen, &values);
-    DebugOnly<DenseElementResult> result = CallBoxedOrUnboxedSpecialization(functor, obj);
-    MOZ_ASSERT(result.value == DenseElementResult::Success);
-
-    obj->setGroup(group);
-
-    ArrayObject* aobj = &obj->as<ArrayObject>();
-    aobj->setLastPropertyMakeNative(cx, shape);
-
-    // Make sure there is at least one element, so that this array does not
-    // use emptyObjectElements / emptyObjectElementsShared.
-    if (!aobj->ensureElements(cx, Max<size_t>(initlen, 1)))
-        return false;
-
-    MOZ_ASSERT(!aobj->getDenseInitializedLength());
-    aobj->setDenseInitializedLength(initlen);
-    aobj->initDenseElements(0, values.begin(), initlen);
-    aobj->setLengthInt32(length);
-
-    return true;
-}
-
-/* static */ bool
-UnboxedArrayObject::convertToNative(JSContext* cx, JSObject* obj)
-{
-    const UnboxedLayout& layout = obj->as<UnboxedArrayObject>().layout();
-
-    if (!layout.nativeGroup()) {
-        if (!UnboxedLayout::makeNativeGroup(cx, obj->group()))
-            return false;
-    }
-
-    return convertToNativeWithGroup(cx, obj, layout.nativeGroup(), layout.nativeShape());
-}
-
-bool
-UnboxedArrayObject::convertInt32ToDouble(ExclusiveContext* cx, ObjectGroup* group)
-{
-    MOZ_ASSERT(elementType() == JSVAL_TYPE_INT32);
-    MOZ_ASSERT(group->unboxedLayout().elementType() == JSVAL_TYPE_DOUBLE);
-
-    Vector<int32_t> values(cx);
-    if (!values.reserve(initializedLength()))
-        return false;
-    for (size_t i = 0; i < initializedLength(); i++)
-        values.infallibleAppend(getElementSpecific<JSVAL_TYPE_INT32>(i).toInt32());
-
-    uint8_t* newElements;
-    if (hasInlineElements()) {
-        newElements = AllocateObjectBuffer<uint8_t>(cx, this, capacity() * sizeof(double));
-    } else {
-        newElements = ReallocateObjectBuffer<uint8_t>(cx, this, elements(),
-                                                      capacity() * sizeof(int32_t),
-                                                      capacity() * sizeof(double));
-    }
-    if (!newElements)
-        return false;
-
-    setGroup(group);
-    elements_ = newElements;
-
-    for (size_t i = 0; i < initializedLength(); i++)
-        setElementNoTypeChangeSpecific<JSVAL_TYPE_DOUBLE>(i, DoubleValue(values[i]));
-
-    return true;
-}
-
-/* static */ UnboxedArrayObject*
-UnboxedArrayObject::create(ExclusiveContext* cx, HandleObjectGroup group, uint32_t length,
-                           NewObjectKind newKind, uint32_t maxLength)
-{
-    MOZ_ASSERT(length <= MaximumCapacity);
-
-    MOZ_ASSERT(group->clasp() == &class_);
-    uint32_t elementSize = UnboxedTypeSize(group->unboxedLayout().elementType());
-    uint32_t capacity = Min(length, maxLength);
-    uint32_t nbytes = offsetOfInlineElements() + elementSize * capacity;
-
-    UnboxedArrayObject* res;
-    if (nbytes <= JSObject::MAX_BYTE_SIZE) {
-        gc::AllocKind allocKind = gc::GetGCObjectKindForBytes(nbytes);
-
-        // If there was no provided length information, pick an allocation kind
-        // to accommodate small arrays (as is done for normal native arrays).
-        if (capacity == 0)
-            allocKind = gc::AllocKind::OBJECT8;
-
-        res = NewObjectWithGroup<UnboxedArrayObject>(cx, group, allocKind, newKind);
-        if (!res)
-            return nullptr;
-        res->setInitializedLengthNoBarrier(0);
-        res->setInlineElements();
-
-        size_t actualCapacity = (GetGCKindBytes(allocKind) - offsetOfInlineElements()) / elementSize;
-        MOZ_ASSERT(actualCapacity >= capacity);
-        res->setCapacityIndex(exactCapacityIndex(actualCapacity));
-    } else {
-        res = NewObjectWithGroup<UnboxedArrayObject>(cx, group, gc::AllocKind::OBJECT0, newKind);
-        if (!res)
-            return nullptr;
-        res->setInitializedLengthNoBarrier(0);
-
-        uint32_t capacityIndex = (capacity == length)
-                                 ? CapacityMatchesLengthIndex
-                                 : chooseCapacityIndex(capacity, length);
-        uint32_t actualCapacity = computeCapacity(capacityIndex, length);
-
-        res->elements_ = AllocateObjectBuffer<uint8_t>(cx, res, actualCapacity * elementSize);
-        if (!res->elements_) {
-            // Make the object safe for GC.
-            res->setInlineElements();
-            return nullptr;
-        }
-
-        res->setCapacityIndex(capacityIndex);
-    }
-
-    res->setLength(cx, length);
-    return res;
-}
-
-bool
-UnboxedArrayObject::setElement(ExclusiveContext* cx, size_t index, const Value& v)
-{
-    MOZ_ASSERT(index < initializedLength());
-    uint8_t* p = elements() + index * elementSize();
-    return SetUnboxedValue(cx, this, JSID_VOID, p, elementType(), v, /* preBarrier = */ true);
-}
-
-bool
-UnboxedArrayObject::initElement(ExclusiveContext* cx, size_t index, const Value& v)
-{
-    MOZ_ASSERT(index < initializedLength());
-    uint8_t* p = elements() + index * elementSize();
-    return SetUnboxedValue(cx, this, JSID_VOID, p, elementType(), v, /* preBarrier = */ false);
-}
-
-void
-UnboxedArrayObject::initElementNoTypeChange(size_t index, const Value& v)
-{
-    MOZ_ASSERT(index < initializedLength());
-    uint8_t* p = elements() + index * elementSize();
-    if (UnboxedTypeNeedsPreBarrier(elementType()))
-        *reinterpret_cast<void**>(p) = nullptr;
-    SetUnboxedValueNoTypeChange(this, p, elementType(), v, /* preBarrier = */ false);
-}
-
-Value
-UnboxedArrayObject::getElement(size_t index)
-{
-    MOZ_ASSERT(index < initializedLength());
-    uint8_t* p = elements() + index * elementSize();
-    return GetUnboxedValue(p, elementType(), /* maybeUninitialized = */ false);
-}
-
-/* static */ void
-UnboxedArrayObject::trace(JSTracer* trc, JSObject* obj)
-{
-    JSValueType type = obj->as<UnboxedArrayObject>().elementType();
-    if (!UnboxedTypeNeedsPreBarrier(type))
-        return;
-
-    MOZ_ASSERT(obj->as<UnboxedArrayObject>().elementSize() == sizeof(uintptr_t));
-    size_t initlen = obj->as<UnboxedArrayObject>().initializedLength();
-    void** elements = reinterpret_cast<void**>(obj->as<UnboxedArrayObject>().elements());
-
-    switch (type) {
-      case JSVAL_TYPE_OBJECT:
-        for (size_t i = 0; i < initlen; i++) {
-            GCPtrObject* heap = reinterpret_cast<GCPtrObject*>(elements + i);
-            TraceNullableEdge(trc, heap, "unboxed_object");
-        }
-        break;
-
-      case JSVAL_TYPE_STRING:
-        for (size_t i = 0; i < initlen; i++) {
-            GCPtrString* heap = reinterpret_cast<GCPtrString*>(elements + i);
-            TraceEdge(trc, heap, "unboxed_string");
-        }
-        break;
-
-      default:
-        MOZ_CRASH();
-    }
-}
-
-/* static */ void
-UnboxedArrayObject::objectMoved(JSObject* obj, const JSObject* old)
-{
-    UnboxedArrayObject& dst = obj->as<UnboxedArrayObject>();
-    const UnboxedArrayObject& src = old->as<UnboxedArrayObject>();
-
-    // Fix up possible inline data pointer.
-    if (src.hasInlineElements())
-        dst.setInlineElements();
-}
-
-/* static */ void
-UnboxedArrayObject::finalize(FreeOp* fop, JSObject* obj)
-{
-    MOZ_ASSERT(!IsInsideNursery(obj));
-    if (!obj->as<UnboxedArrayObject>().hasInlineElements())
-        js_free(obj->as<UnboxedArrayObject>().elements());
-}
-
-/* static */ size_t
-UnboxedArrayObject::objectMovedDuringMinorGC(JSTracer* trc, JSObject* dst, JSObject* src,
-                                             gc::AllocKind allocKind)
-{
-    UnboxedArrayObject* ndst = &dst->as<UnboxedArrayObject>();
-    UnboxedArrayObject* nsrc = &src->as<UnboxedArrayObject>();
-    MOZ_ASSERT(ndst->elements() == nsrc->elements());
-
-    Nursery& nursery = trc->runtime()->gc.nursery;
-
-    if (!nursery.isInside(nsrc->elements())) {
-        nursery.removeMallocedBuffer(nsrc->elements());
-        return 0;
-    }
-
-    // Determine if we can use inline data for the target array. If this is
-    // possible, the nursery will have picked an allocation size that is large
-    // enough.
-    size_t nbytes = nsrc->capacity() * nsrc->elementSize();
-    if (offsetOfInlineElements() + nbytes <= GetGCKindBytes(allocKind)) {
-        ndst->setInlineElements();
-    } else {
-        MOZ_ASSERT(allocKind == gc::AllocKind::OBJECT0);
-
-        AutoEnterOOMUnsafeRegion oomUnsafe;
-        uint8_t* data = nsrc->zone()->pod_malloc<uint8_t>(nbytes);
-        if (!data)
-            oomUnsafe.crash("Failed to allocate unboxed array elements while tenuring.");
-        ndst->elements_ = data;
-    }
-
-    PodCopy(ndst->elements(), nsrc->elements(), nsrc->initializedLength() * nsrc->elementSize());
-
-    // Set a forwarding pointer for the element buffers in case they were
-    // preserved on the stack by Ion.
-    bool direct = nsrc->capacity() * nsrc->elementSize() >= sizeof(uintptr_t);
-    nursery.maybeSetForwardingPointer(trc, nsrc->elements(), ndst->elements(), direct);
-
-    return ndst->hasInlineElements() ? 0 : nbytes;
-}
-
-// Possible capacities for unboxed arrays. Some of these capacities might seem
-// a little weird, but were chosen to allow the inline data of objects of each
-// size to be fully utilized for arrays of the various types on both 32 bit and
-// 64 bit platforms.
-//
-// To find the possible inline capacities, the following script was used:
-//
-// var fixedSlotCapacities = [0, 2, 4, 8, 12, 16];
-// var dataSizes = [1, 4, 8];
-// var header32 = 4 * 2 + 4 * 2;
-// var header64 = 8 * 2 + 4 * 2;
-//
-// for (var i = 0; i < fixedSlotCapacities.length; i++) {
-//    var nfixed = fixedSlotCapacities[i];
-//    var size32 = 4 * 4 + 8 * nfixed - header32;
-//    var size64 = 8 * 4 + 8 * nfixed - header64;
-//    for (var j = 0; j < dataSizes.length; j++) {
-//        print(size32 / dataSizes[j]);
-//        print(size64 / dataSizes[j]);
-//    }
-// }
-//
-/* static */ const uint32_t
-UnboxedArrayObject::CapacityArray[] = {
-    UINT32_MAX, // For CapacityMatchesLengthIndex.
-    0, 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 13, 16, 17, 18, 24, 26, 32, 34, 40, 64, 72, 96, 104, 128, 136,
-    256, 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536, 131072, 262144, 524288,
-    1048576, 2097152, 3145728, 4194304, 5242880, 6291456, 7340032, 8388608, 9437184, 11534336,
-    13631488, 15728640, 17825792, 20971520, 24117248, 27262976, 31457280, 35651584, 40894464,
-    46137344, 52428800, 59768832, MaximumCapacity
-};
-
-static const uint32_t
-Pow2CapacityIndexes[] = {
-    2,  // 1
-    3,  // 2
-    5,  // 4
-    8,  // 8
-    13, // 16
-    18, // 32
-    21, // 64
-    25, // 128
-    27, // 256
-    28, // 512
-    29, // 1024
-    30, // 2048
-    31, // 4096
-    32, // 8192
-    33, // 16384
-    34, // 32768
-    35, // 65536
-    36, // 131072
-    37, // 262144
-    38, // 524288
-    39  // 1048576
-};
-
-static const uint32_t MebiCapacityIndex = 39;
-
-/* static */ uint32_t
-UnboxedArrayObject::chooseCapacityIndex(uint32_t capacity, uint32_t length)
-{
-    // Note: the structure and behavior of this method follow along with
-    // NativeObject::goodAllocated. Changes to the allocation strategy in one
-    // should generally be matched by the other.
-
-    // Make sure we have enough space to store all possible values for the capacity index.
-    // This ought to be a static_assert, but MSVC doesn't like that.
-    MOZ_ASSERT(mozilla::ArrayLength(CapacityArray) - 1 <= (CapacityMask >> CapacityShift));
-
-    // The caller should have ensured the capacity is possible for an unboxed array.
-    MOZ_ASSERT(capacity <= MaximumCapacity);
-
-    static const uint32_t Mebi = 1024 * 1024;
-
-    if (capacity <= Mebi) {
-        capacity = mozilla::RoundUpPow2(capacity);
-
-        // When the required capacity is close to the array length, then round
-        // up to the array length itself, as for NativeObject.
-        if (length >= capacity && capacity > (length / 3) * 2)
-            return CapacityMatchesLengthIndex;
-
-        if (capacity < MinimumDynamicCapacity)
-            capacity = MinimumDynamicCapacity;
-
-        uint32_t bit = mozilla::FloorLog2Size(capacity);
-        MOZ_ASSERT(capacity == uint32_t(1 << bit));
-        MOZ_ASSERT(bit <= 20);
-        MOZ_ASSERT(mozilla::ArrayLength(Pow2CapacityIndexes) == 21);
-
-        uint32_t index = Pow2CapacityIndexes[bit];
-        MOZ_ASSERT(CapacityArray[index] == capacity);
-
-        return index;
-    }
-
-    MOZ_ASSERT(CapacityArray[MebiCapacityIndex] == Mebi);
-
-    for (uint32_t i = MebiCapacityIndex + 1;; i++) {
-        if (CapacityArray[i] >= capacity)
-            return i;
-    }
-
-    MOZ_CRASH("Invalid capacity");
-}
-
-/* static */ uint32_t
-UnboxedArrayObject::exactCapacityIndex(uint32_t capacity)
-{
-    for (size_t i = CapacityMatchesLengthIndex + 1; i < ArrayLength(CapacityArray); i++) {
-        if (CapacityArray[i] == capacity)
-            return i;
-    }
-    MOZ_CRASH();
-}
-
-bool
-UnboxedArrayObject::growElements(ExclusiveContext* cx, size_t cap)
-{
-    // The caller should have checked if this capacity is possible for an
-    // unboxed array, so the only way this call can fail is from OOM.
-    MOZ_ASSERT(cap <= MaximumCapacity);
-
-    uint32_t oldCapacity = capacity();
-    uint32_t newCapacityIndex = chooseCapacityIndex(cap, length());
-    uint32_t newCapacity = computeCapacity(newCapacityIndex, length());
-
-    MOZ_ASSERT(oldCapacity < cap);
-    MOZ_ASSERT(cap <= newCapacity);
-
-    // The allocation size computation below cannot have integer overflows.
-    JS_STATIC_ASSERT(MaximumCapacity < UINT32_MAX / sizeof(double));
-
-    uint8_t* newElements;
-    if (hasInlineElements()) {
-        newElements = AllocateObjectBuffer<uint8_t>(cx, this, newCapacity * elementSize());
-        if (!newElements)
-            return false;
-        js_memcpy(newElements, elements(), initializedLength() * elementSize());
-    } else {
-        newElements = ReallocateObjectBuffer<uint8_t>(cx, this, elements(),
-                                                      oldCapacity * elementSize(),
-                                                      newCapacity * elementSize());
-        if (!newElements)
-            return false;
-    }
-
-    elements_ = newElements;
-    setCapacityIndex(newCapacityIndex);
-
-    return true;
-}
-
-void
-UnboxedArrayObject::shrinkElements(ExclusiveContext* cx, size_t cap)
-{
-    if (hasInlineElements())
-        return;
-
-    uint32_t oldCapacity = capacity();
-    uint32_t newCapacityIndex = chooseCapacityIndex(cap, 0);
-    uint32_t newCapacity = computeCapacity(newCapacityIndex, 0);
-
-    MOZ_ASSERT(cap < oldCapacity);
-    MOZ_ASSERT(cap <= newCapacity);
-
-    if (newCapacity >= oldCapacity)
-        return;
-
-    uint8_t* newElements = ReallocateObjectBuffer<uint8_t>(cx, this, elements(),
-                                                           oldCapacity * elementSize(),
-                                                           newCapacity * elementSize());
-    if (!newElements)
-        return;
-
-    elements_ = newElements;
-    setCapacityIndex(newCapacityIndex);
-}
-
-bool
-UnboxedArrayObject::containsProperty(ExclusiveContext* cx, jsid id)
-{
-    if (JSID_IS_INT(id) && uint32_t(JSID_TO_INT(id)) < initializedLength())
-        return true;
-    if (JSID_IS_ATOM(id) && JSID_TO_ATOM(id) == cx->names().length)
-        return true;
-    return false;
-}
-
-/* static */ bool
-UnboxedArrayObject::obj_lookupProperty(JSContext* cx, HandleObject obj,
-                                       HandleId id, MutableHandleObject objp,
-                                       MutableHandleShape propp)
-{
-    if (obj->as<UnboxedArrayObject>().containsProperty(cx, id)) {
-        MarkNonNativePropertyFound<CanGC>(propp);
-        objp.set(obj);
-        return true;
-    }
-
-    RootedObject proto(cx, obj->staticPrototype());
-    if (!proto) {
-        objp.set(nullptr);
-        propp.set(nullptr);
-        return true;
-    }
-
-    return LookupProperty(cx, proto, id, objp, propp);
-}
-
-/* static */ bool
-UnboxedArrayObject::obj_defineProperty(JSContext* cx, HandleObject obj, HandleId id,
-                                       Handle<PropertyDescriptor> desc,
-                                       ObjectOpResult& result)
-{
-    if (JSID_IS_INT(id) && !desc.getter() && !desc.setter() && desc.attributes() == JSPROP_ENUMERATE) {
-        UnboxedArrayObject* nobj = &obj->as<UnboxedArrayObject>();
-
-        uint32_t index = JSID_TO_INT(id);
-        if (index < nobj->initializedLength()) {
-            if (nobj->setElement(cx, index, desc.value()))
-                return result.succeed();
-        } else if (index == nobj->initializedLength() && index < MaximumCapacity) {
-            if (nobj->initializedLength() == nobj->capacity()) {
-                if (!nobj->growElements(cx, index + 1))
-                    return false;
-            }
-            nobj->setInitializedLength(index + 1);
-            if (nobj->initElement(cx, index, desc.value())) {
-                if (nobj->length() <= index)
-                    nobj->setLengthInt32(index + 1);
-                return result.succeed();
-            }
-            nobj->setInitializedLengthNoBarrier(index);
-        }
-    }
-
-    if (!convertToNative(cx, obj))
-        return false;
-
-    return DefineProperty(cx, obj, id, desc, result);
-}
-
-/* static */ bool
-UnboxedArrayObject::obj_hasProperty(JSContext* cx, HandleObject obj, HandleId id, bool* foundp)
-{
-    if (obj->as<UnboxedArrayObject>().containsProperty(cx, id)) {
-        *foundp = true;
-        return true;
-    }
-
-    RootedObject proto(cx, obj->staticPrototype());
-    if (!proto) {
-        *foundp = false;
-        return true;
-    }
-
-    return HasProperty(cx, proto, id, foundp);
-}
-
-/* static */ bool
-UnboxedArrayObject::obj_getProperty(JSContext* cx, HandleObject obj, HandleValue receiver,
-                                    HandleId id, MutableHandleValue vp)
-{
-    if (obj->as<UnboxedArrayObject>().containsProperty(cx, id)) {
-        if (JSID_IS_INT(id))
-            vp.set(obj->as<UnboxedArrayObject>().getElement(JSID_TO_INT(id)));
-        else
-            vp.set(Int32Value(obj->as<UnboxedArrayObject>().length()));
-        return true;
-    }
-
-    RootedObject proto(cx, obj->staticPrototype());
-    if (!proto) {
-        vp.setUndefined();
-        return true;
-    }
-
-    return GetProperty(cx, proto, receiver, id, vp);
-}
-
-/* static */ bool
-UnboxedArrayObject::obj_setProperty(JSContext* cx, HandleObject obj, HandleId id, HandleValue v,
-                                    HandleValue receiver, ObjectOpResult& result)
-{
-    if (obj->as<UnboxedArrayObject>().containsProperty(cx, id)) {
-        if (receiver.isObject() && obj == &receiver.toObject()) {
-            if (JSID_IS_INT(id)) {
-                if (obj->as<UnboxedArrayObject>().setElement(cx, JSID_TO_INT(id), v))
-                    return result.succeed();
-            } else {
-                uint32_t len;
-                if (!CanonicalizeArrayLengthValue(cx, v, &len))
-                    return false;
-                UnboxedArrayObject* nobj = &obj->as<UnboxedArrayObject>();
-                if (len < nobj->initializedLength()) {
-                    nobj->setInitializedLength(len);
-                    nobj->shrinkElements(cx, len);
-                }
-                nobj->setLength(cx, len);
-                return result.succeed();
-            }
-
-            if (!convertToNative(cx, obj))
-                return false;
-            return SetProperty(cx, obj, id, v, receiver, result);
-        }
-
-        return SetPropertyByDefining(cx, id, v, receiver, result);
-    }
-
-    return SetPropertyOnProto(cx, obj, id, v, receiver, result);
-}
-
-/* static */ bool
-UnboxedArrayObject::obj_getOwnPropertyDescriptor(JSContext* cx, HandleObject obj, HandleId id,
-                                                 MutableHandle<PropertyDescriptor> desc)
-{
-    if (obj->as<UnboxedArrayObject>().containsProperty(cx, id)) {
-        if (JSID_IS_INT(id)) {
-            desc.value().set(obj->as<UnboxedArrayObject>().getElement(JSID_TO_INT(id)));
-            desc.setAttributes(JSPROP_ENUMERATE);
-        } else {
-            desc.value().set(Int32Value(obj->as<UnboxedArrayObject>().length()));
-            desc.setAttributes(JSPROP_PERMANENT);
-        }
-        desc.object().set(obj);
-        return true;
-    }
-
-    desc.object().set(nullptr);
-    return true;
-}
-
-/* static */ bool
-UnboxedArrayObject::obj_deleteProperty(JSContext* cx, HandleObject obj, HandleId id,
-                                       ObjectOpResult& result)
-{
-    if (obj->as<UnboxedArrayObject>().containsProperty(cx, id)) {
-        size_t initlen = obj->as<UnboxedArrayObject>().initializedLength();
-        if (JSID_IS_INT(id) && JSID_TO_INT(id) == int32_t(initlen - 1)) {
-            obj->as<UnboxedArrayObject>().setInitializedLength(initlen - 1);
-            obj->as<UnboxedArrayObject>().shrinkElements(cx, initlen - 1);
-            return result.succeed();
-        }
-    }
-
-    if (!convertToNative(cx, obj))
-        return false;
-    return DeleteProperty(cx, obj, id, result);
-}
-
-/* static */ bool
-UnboxedArrayObject::obj_watch(JSContext* cx, HandleObject obj, HandleId id, HandleObject callable)
-{
-    if (!convertToNative(cx, obj))
-        return false;
-    return WatchProperty(cx, obj, id, callable);
-}
-
-/* static */ bool
-UnboxedArrayObject::obj_enumerate(JSContext* cx, HandleObject obj, AutoIdVector& properties,
-                                  bool enumerableOnly)
-{
-    for (size_t i = 0; i < obj->as<UnboxedArrayObject>().initializedLength(); i++) {
-        if (!properties.append(INT_TO_JSID(i)))
-            return false;
-    }
-
-    if (!enumerableOnly && !properties.append(NameToId(cx->names().length)))
-        return false;
-
-    return true;
-}
-
-static const ClassOps UnboxedArrayObjectClassOps = {
-    nullptr,        /* addProperty */
-    nullptr,        /* delProperty */
-    nullptr,        /* getProperty */
-    nullptr,        /* setProperty */
-    nullptr,        /* enumerate   */
-    nullptr,        /* resolve     */
-    nullptr,        /* mayResolve  */
-    UnboxedArrayObject::finalize,
-    nullptr,        /* call        */
-    nullptr,        /* hasInstance */
-    nullptr,        /* construct   */
-    UnboxedArrayObject::trace,
-};
-
-static const ClassExtension UnboxedArrayObjectClassExtension = {
-    nullptr,    /* weakmapKeyDelegateOp */
-    UnboxedArrayObject::objectMoved
-};
-
-static const ObjectOps UnboxedArrayObjectObjectOps = {
-    UnboxedArrayObject::obj_lookupProperty,
-    UnboxedArrayObject::obj_defineProperty,
-    UnboxedArrayObject::obj_hasProperty,
-    UnboxedArrayObject::obj_getProperty,
-    UnboxedArrayObject::obj_setProperty,
-    UnboxedArrayObject::obj_getOwnPropertyDescriptor,
-    UnboxedArrayObject::obj_deleteProperty,
-    UnboxedArrayObject::obj_watch,
-    nullptr,   /* No unwatch needed, as watch() converts the object to native */
-    nullptr,   /* getElements */
-    UnboxedArrayObject::obj_enumerate,
-    nullptr    /* funToString */
-};
-
-const Class UnboxedArrayObject::class_ = {
-    "Array",
-    Class::NON_NATIVE |
-    JSCLASS_SKIP_NURSERY_FINALIZE |
-    JSCLASS_BACKGROUND_FINALIZE,
-    &UnboxedArrayObjectClassOps,
-    JS_NULL_CLASS_SPEC,
-    &UnboxedArrayObjectClassExtension,
-    &UnboxedArrayObjectObjectOps
-};
-
-/////////////////////////////////////////////////////////////////////
-// API
-/////////////////////////////////////////////////////////////////////
-
-static inline Value
-NextValue(Handle<GCVector<Value>> values, size_t* valueCursor)
-{
-    return values[(*valueCursor)++];
-}
-
-void
-UnboxedArrayObject::fillAfterConvert(ExclusiveContext* cx,
-                                     Handle<GCVector<Value>> values, size_t* valueCursor)
-{
-    MOZ_ASSERT(CapacityArray[1] == 0);
-    setCapacityIndex(1);
-    setInitializedLengthNoBarrier(0);
-    setInlineElements();
-
-    setLength(cx, NextValue(values, valueCursor).toInt32());
-
-    int32_t initlen = NextValue(values, valueCursor).toInt32();
-    if (!initlen)
-        return;
-
-    AutoEnterOOMUnsafeRegion oomUnsafe;
-    if (!growElements(cx, initlen))
-        oomUnsafe.crash("UnboxedArrayObject::fillAfterConvert");
-
-    setInitializedLength(initlen);
-
-    for (size_t i = 0; i < size_t(initlen); i++)
-        JS_ALWAYS_TRUE(initElement(cx, i, NextValue(values, valueCursor)));
-}
-
-void
-UnboxedPlainObject::fillAfterConvert(ExclusiveContext* cx,
-                                     Handle<GCVector<Value>> values, size_t* valueCursor)
-{
-    initExpando();
-    memset(data(), 0, layout().size());
-    for (size_t i = 0; i < layout().properties().length(); i++)
-        JS_ALWAYS_TRUE(setValue(cx, layout().properties()[i], NextValue(values, valueCursor)));
-}
-
-DefineBoxedOrUnboxedFunctor6(SetOrExtendBoxedOrUnboxedDenseElements,
-                             ExclusiveContext*, JSObject*, uint32_t, const Value*, uint32_t,
-                             ShouldUpdateTypes);
-
-DenseElementResult
-js::SetOrExtendAnyBoxedOrUnboxedDenseElements(ExclusiveContext* cx, JSObject* obj,
-                                              uint32_t start, const Value* vp, uint32_t count,
-                                              ShouldUpdateTypes updateTypes)
-{
-    SetOrExtendBoxedOrUnboxedDenseElementsFunctor functor(cx, obj, start, vp, count, updateTypes);
-    return CallBoxedOrUnboxedSpecialization(functor, obj);
-};
-
-DefineBoxedOrUnboxedFunctor5(MoveBoxedOrUnboxedDenseElements,
-                             JSContext*, JSObject*, uint32_t, uint32_t, uint32_t);
-
-DenseElementResult
-js::MoveAnyBoxedOrUnboxedDenseElements(JSContext* cx, JSObject* obj,
-                                       uint32_t dstStart, uint32_t srcStart, uint32_t length)
-{
-    MoveBoxedOrUnboxedDenseElementsFunctor functor(cx, obj, dstStart, srcStart, length);
-    return CallBoxedOrUnboxedSpecialization(functor, obj);
-}
-
-DefineBoxedOrUnboxedFunctorPair6(CopyBoxedOrUnboxedDenseElements,
-                                 JSContext*, JSObject*, JSObject*, uint32_t, uint32_t, uint32_t);
-
-DenseElementResult
-js::CopyAnyBoxedOrUnboxedDenseElements(JSContext* cx, JSObject* dst, JSObject* src,
-                                       uint32_t dstStart, uint32_t srcStart, uint32_t length)
-{
-    CopyBoxedOrUnboxedDenseElementsFunctor functor(cx, dst, src, dstStart, srcStart, length);
-    return CallBoxedOrUnboxedSpecialization(functor, dst, src);
-}
-
-DefineBoxedOrUnboxedFunctor3(SetBoxedOrUnboxedInitializedLength,
-                             JSContext*, JSObject*, size_t);
-
-void
-js::SetAnyBoxedOrUnboxedInitializedLength(JSContext* cx, JSObject* obj, size_t initlen)
-{
-    SetBoxedOrUnboxedInitializedLengthFunctor functor(cx, obj, initlen);
-    JS_ALWAYS_TRUE(CallBoxedOrUnboxedSpecialization(functor, obj) == DenseElementResult::Success);
-}
-
-DefineBoxedOrUnboxedFunctor3(EnsureBoxedOrUnboxedDenseElements,
-                             JSContext*, JSObject*, size_t);
-
-DenseElementResult
-js::EnsureAnyBoxedOrUnboxedDenseElements(JSContext* cx, JSObject* obj, size_t initlen)
-{
-    EnsureBoxedOrUnboxedDenseElementsFunctor functor(cx, obj, initlen);
-    return CallBoxedOrUnboxedSpecialization(functor, obj);
-}