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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef vm_ArrayObject_h
#define vm_ArrayObject_h
#include "vm/NativeObject.h"
namespace js {
class AutoSetNewObjectMetadata;
class ArrayObject : public NativeObject
{
public:
// Array(x) eagerly allocates dense elements if x <= this value. Without
// the subtraction the max would roll over to the next power-of-two (4096)
// due to the way that growElements() and goodAllocated() work.
static const uint32_t EagerAllocationMaxLength = 2048 - ObjectElements::VALUES_PER_HEADER;
static const Class class_;
bool lengthIsWritable() const {
return !getElementsHeader()->hasNonwritableArrayLength();
}
uint32_t length() const {
return getElementsHeader()->length;
}
inline void setLength(ExclusiveContext* cx, uint32_t length);
// Variant of setLength for use on arrays where the length cannot overflow int32_t.
void setLengthInt32(uint32_t length) {
MOZ_ASSERT(lengthIsWritable());
MOZ_ASSERT(length <= INT32_MAX);
getElementsHeader()->length = length;
}
// Make an array object with the specified initial state.
static inline ArrayObject*
createArray(ExclusiveContext* cx,
gc::AllocKind kind,
gc::InitialHeap heap,
HandleShape shape,
HandleObjectGroup group,
uint32_t length,
AutoSetNewObjectMetadata& metadata);
// Make a copy-on-write array object which shares the elements of an
// existing object.
static inline ArrayObject*
createCopyOnWriteArray(ExclusiveContext* cx,
gc::InitialHeap heap,
HandleArrayObject sharedElementsOwner);
private:
// Helper for the above methods.
static inline ArrayObject*
createArrayInternal(ExclusiveContext* cx,
gc::AllocKind kind,
gc::InitialHeap heap,
HandleShape shape,
HandleObjectGroup group,
AutoSetNewObjectMetadata&);
static inline ArrayObject*
finishCreateArray(ArrayObject* obj, HandleShape shape, AutoSetNewObjectMetadata& metadata);
};
} // namespace js
#endif // vm_ArrayObject_h
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