/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#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 JSClass class_;
bool lengthIsWritable()
const {
return !getElementsHeader()->hasNonwritableArrayLength();
}
uint32_t length()
const {
return getElementsHeader()->length; }
void setNonWritableLength(JSContext* cx) {
shrinkCapacityToInitializedLength(cx);
getElementsHeader()->setNonwritableArrayLength();
}
void setLength(uint32_t length) {
MOZ_ASSERT(lengthIsWritable());
MOZ_ASSERT_IF(length != getElementsHeader()->length,
!denseElementsAreFrozen());
getElementsHeader()->length = length;
}
// Try to add a new dense element to this array. The array must be extensible.
//
// Returns DenseElementResult::Incomplete if `index >= length`, if the array
// has sparse elements, if we're adding a sparse element, or if the array
// already contains a dense element at this index.
inline DenseElementResult addDenseElementNoLengthChange(JSContext* cx,
uint32_t index,
const Value& val);
// Make an array object with the specified initial state.
static MOZ_ALWAYS_INLINE ArrayObject* create(
JSContext* cx, gc::AllocKind kind, gc::Heap heap,
Handle<SharedShape*> shape, uint32_t length, uint32_t slotSpan,
AutoSetNewObjectMetadata& metadata, gc::AllocSite* site = nullptr);
};
}
// namespace js
#endif // vm_ArrayObject_h
