/*
* Copyright (C) 1999-2000 Harri Porten (porten@kde.org)
* Copyright (C) 2003, 2007, 2008, 2009 Apple Inc. All rights reserved.
* Copyright (C) 2003 Peter Kelly (pmk@post.com)
* Copyright (C) 2006 Alexey Proskuryakov (ap@nypop.com)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include "config.h"
#include "JSArray.h"
#include "ArrayPrototype.h"
#include "CachedCall.h"
#include "Error.h"
#include "Executable.h"
#include "PropertyNameArray.h"
#include <wtf/AVLTree.h>
#include <wtf/Assertions.h>
#include <wtf/OwnPtr.h>
#include <Operations.h>
#define CHECK_ARRAY_CONSISTENCY 0
using namespace std;
using namespace WTF;
namespace JSC {
ASSERT_CLASS_FITS_IN_CELL(JSArray);
// Overview of JSArray
//
// Properties of JSArray objects may be stored in one of three locations:
// * The regular JSObject property map.
// * A storage vector.
// * A sparse map of array entries.
//
// Properties with non-numeric identifiers, with identifiers that are not representable
// as an unsigned integer, or where the value is greater than MAX_ARRAY_INDEX
// (specifically, this is only one property - the value 0xFFFFFFFFU as an unsigned 32-bit
// integer) are not considered array indices and will be stored in the JSObject property map.
//
// All properties with a numeric identifer, representable as an unsigned integer i,
// where (i <= MAX_ARRAY_INDEX), are an array index and will be stored in either the
// storage vector or the sparse map. An array index i will be handled in the following
// fashion:
//
// * Where (i < MIN_SPARSE_ARRAY_INDEX) the value will be stored in the storage vector.
// * Where (MIN_SPARSE_ARRAY_INDEX <= i <= MAX_STORAGE_VECTOR_INDEX) the value will either
// be stored in the storage vector or in the sparse array, depending on the density of
// data that would be stored in the vector (a vector being used where at least
// (1 / minDensityMultiplier) of the entries would be populated).
// * Where (MAX_STORAGE_VECTOR_INDEX < i <= MAX_ARRAY_INDEX) the value will always be stored
// in the sparse array.
// The definition of MAX_STORAGE_VECTOR_LENGTH is dependant on the definition storageSize
// function below - the MAX_STORAGE_VECTOR_LENGTH limit is defined such that the storage
// size calculation cannot overflow. (sizeof(ArrayStorage) - sizeof(JSValue)) +
// (vectorLength * sizeof(JSValue)) must be <= 0xFFFFFFFFU (which is maximum value of size_t).
#define MAX_STORAGE_VECTOR_LENGTH static_cast<unsigned>((0xFFFFFFFFU - (sizeof(ArrayStorage) - sizeof(JSValue))) / sizeof(JSValue))
// These values have to be macros to be used in max() and min() without introducing
// a PIC branch in Mach-O binaries, see <rdar://problem/5971391>.
#define MIN_SPARSE_ARRAY_INDEX 10000U
#define MAX_STORAGE_VECTOR_INDEX (MAX_STORAGE_VECTOR_LENGTH - 1)
// 0xFFFFFFFF is a bit weird -- is not an array index even though it's an integer.
#define MAX_ARRAY_INDEX 0xFFFFFFFEU
// Our policy for when to use a vector and when to use a sparse map.
// For all array indices under MIN_SPARSE_ARRAY_INDEX, we always use a vector.
// When indices greater than MIN_SPARSE_ARRAY_INDEX are involved, we use a vector
// as long as it is 1/8 full. If more sparse than that, we use a map.
static const unsigned minDensityMultiplier = 8;
const ClassInfo JSArray::info = {"Array", 0, 0, 0};
static inline size_t storageSize(unsigned vectorLength)
{
ASSERT(vectorLength <= MAX_STORAGE_VECTOR_LENGTH);
// MAX_STORAGE_VECTOR_LENGTH is defined such that provided (vectorLength <= MAX_STORAGE_VECTOR_LENGTH)
// - as asserted above - the following calculation cannot overflow.
size_t size = (sizeof(ArrayStorage) - sizeof(JSValue)) + (vectorLength * sizeof(JSValue));
// Assertion to detect integer overflow in previous calculation (should not be possible, provided that
// MAX_STORAGE_VECTOR_LENGTH is correctly defined).
ASSERT(((size - (sizeof(ArrayStorage) - sizeof(JSValue))) / sizeof(JSValue) == vectorLength) && (size >= (sizeof(ArrayStorage) - sizeof(JSValue))));
return size;
}
static inline unsigned increasedVectorLength(unsigned newLength)
{
ASSERT(newLength <= MAX_STORAGE_VECTOR_LENGTH);
// Mathematically equivalent to:
// increasedLength = (newLength * 3 + 1) / 2;
// or:
// increasedLength = (unsigned)ceil(newLength * 1.5));
// This form is not prone to internal overflow.
unsigned increasedLength = newLength + (newLength >> 1) + (newLength & 1);
ASSERT(increasedLength >= newLength);
return min(increasedLength, MAX_STORAGE_VECTOR_LENGTH);
}
static inline bool isDenseEnoughForVector(unsigned length, unsigned numValues)
{
return length / minDensityMultiplier <= numValues;
}
#if !CHECK_ARRAY_CONSISTENCY
inline void JSArray::checkConsistency(ConsistencyCheckType)
{
}
#endif
JSArray::JSArray(NonNullPassRefPtr<Structure> structure)
: JSObject(structure)
{
unsigned initialCapacity = 0;
m_storage = static_cast<ArrayStorage*>(fastZeroedMalloc(storageSize(initialCapacity)));
m_vectorLength = initialCapacity;
checkConsistency();
}
JSArray::JSArray(NonNullPassRefPtr<Structure> structure, unsigned initialLength)
: JSObject(structure)
{
unsigned initialCapacity = min(initialLength, MIN_SPARSE_ARRAY_INDEX);
m_storage = static_cast<ArrayStorage*>(fastMalloc(storageSize(initialCapacity)));
m_storage->m_length = initialLength;
m_vectorLength = initialCapacity;
m_storage->m_numValuesInVector = 0;
m_storage->m_sparseValueMap = 0;
m_storage->lazyCreationData = 0;
m_storage->reportedMapCapacity = 0;
JSValue* vector = m_storage->m_vector;
for (size_t i = 0; i < initialCapacity; ++i)
vector[i] = JSValue();
checkConsistency();
Heap::heap(this)->reportExtraMemoryCost(initialCapacity * sizeof(JSValue));
}
JSArray::JSArray(NonNullPassRefPtr<Structure> structure, const ArgList& list)
: JSObject(structure)
{
unsigned initialCapacity = list.size();
m_storage = static_cast<ArrayStorage*>(fastMalloc(storageSize(initialCapacity)));
m_storage->m_length = initialCapacity;
m_vectorLength = initialCapacity;
m_storage->m_numValuesInVector = initialCapacity;
m_storage->m_sparseValueMap = 0;
m_storage->lazyCreationData = 0;
m_storage->reportedMapCapacity = 0;
size_t i = 0;
ArgList::const_iterator end = list.end();
for (ArgList::const_iterator it = list.begin(); it != end; ++it, ++i)
m_storage->m_vector[i] = *it;
checkConsistency();
Heap::heap(this)->reportExtraMemoryCost(storageSize(initialCapacity));
}
JSArray::~JSArray()
{
ASSERT(vptr() == JSGlobalData::jsArrayVPtr);
checkConsistency(DestructorConsistencyCheck);
delete m_storage->m_sparseValueMap;
fastFree(m_storage);
}
bool JSArray::getOwnPropertySlot(ExecState* exec, unsigned i, PropertySlot& slot)
{
ArrayStorage* storage = m_storage;
if (i >= storage->m_length) {
if (i > MAX_ARRAY_INDEX)
return getOwnPropertySlot(exec, Identifier::from(exec, i), slot);
return false;
}
if (i < m_vectorLength) {
JSValue& valueSlot = storage->m_vector[i];
if (valueSlot) {
slot.setValueSlot(&valueSlot);
return true;
}
} else if (SparseArrayValueMap* map = storage->m_sparseValueMap) {
if (i >= MIN_SPARSE_ARRAY_INDEX) {
SparseArrayValueMap::iterator it = map->find(i);
if (it != map->end()) {
slot.setValueSlot(&it->second);
return true;
}
}
}
return JSObject::getOwnPropertySlot(exec, Identifier::from(exec, i), slot);
}
bool JSArray::getOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
{
if (propertyName == exec->propertyNames().length) {
slot.setValue(jsNumber(exec, length()));
return true;
}
bool isArrayIndex;
unsigned i = propertyName.toArrayIndex(&isArrayIndex);
if (isArrayIndex)
return JSArray::getOwnPropertySlot(exec, i, slot);
return JSObject::getOwnPropertySlot(exec, propertyName, slot);
}
bool JSArray::getOwnPropertyDescriptor(ExecState* exec, const Identifier& propertyName, PropertyDescriptor& descriptor)
{
if (propertyName == exec->propertyNames().length) {
descriptor.setDescriptor(jsNumber(exec, length()), DontDelete | DontEnum);
return true;
}
bool isArrayIndex;
unsigned i = propertyName.toArrayIndex(&isArrayIndex);
if (isArrayIndex) {
if (i >= m_storage->m_length)
return false;
if (i < m_vectorLength) {
JSValue& value = m_storage->m_vector[i];
if (value) {
descriptor.setDescriptor(value, 0);
return true;
}
} else if (SparseArrayValueMap* map = m_storage->m_sparseValueMap) {
if (i >= MIN_SPARSE_ARRAY_INDEX) {
SparseArrayValueMap::iterator it = map->find(i);
if (it != map->end()) {
descriptor.setDescriptor(it->second, 0);
return true;
}
}
}
}
return JSObject::getOwnPropertyDescriptor(exec, propertyName, descriptor);
}
// ECMA 15.4.5.1
void JSArray::put(ExecState* exec, const Identifier& propertyName, JSValue value, PutPropertySlot& slot)
{
bool isArrayIndex;
unsigned i = propertyName.toArrayIndex(&isArrayIndex);
if (isArrayIndex) {
put(exec, i, value);
return;
}
if (propertyName == exec->propertyNames().length) {
unsigned newLength = value.toUInt32(exec);
if (value.toNumber(exec) != static_cast<double>(newLength)) {
throwError(exec, RangeError, "Invalid array length.");
return;
}
setLength(newLength);
return;
}
JSObject::put(exec, propertyName, value, slot);
}
void JSArray::put(ExecState* exec, unsigned i, JSValue value)
{
checkConsistency();
unsigned length = m_storage->m_length;
if (i >= length && i <= MAX_ARRAY_INDEX) {
length = i + 1;
m_storage->m_length = length;
}
if (i < m_vectorLength) {
JSValue& valueSlot = m_storage->m_vector[i];
if (valueSlot) {
valueSlot = value;
checkConsistency();
return;
}
valueSlot = value;
++m_storage->m_numValuesInVector;
checkConsistency();
return;
}
putSlowCase(exec, i, value);
}
NEVER_INLINE void JSArray::putSlowCase(ExecState* exec, unsigned i, JSValue value)
{
ArrayStorage* storage = m_storage;
SparseArrayValueMap* map = storage->m_sparseValueMap;
if (i >= MIN_SPARSE_ARRAY_INDEX) {
if (i > MAX_ARRAY_INDEX) {
PutPropertySlot slot;
put(exec, Identifier::from(exec, i), value, slot);
return;
}
// We miss some cases where we could compact the storage, such as a large array that is being filled from the end
// (which will only be compacted as we reach indices that are less than MIN_SPARSE_ARRAY_INDEX) - but this makes the check much faster.
if ((i > MAX_STORAGE_VECTOR_INDEX) || !isDenseEnoughForVector(i + 1, storage->m_numValuesInVector + 1)) {
if (!map) {
map = new SparseArrayValueMap;
storage->m_sparseValueMap = map;
}
pair<SparseArrayValueMap::iterator, bool> result = map->add(i, value);
if (!result.second) { // pre-existing entry
result.first->second = value;
return;
}
size_t capacity = map->capacity();
if (capacity != storage->reportedMapCapacity) {
Heap::heap(this)->reportExtraMemoryCost((capacity - storage->reportedMapCapacity) * (sizeof(unsigned) + sizeof(JSValue)));
storage->reportedMapCapacity = capacity;
}
return;
}
}
// We have decided that we'll put the new item into the vector.
// Fast case is when there is no sparse map, so we can increase the vector size without moving values from it.
if (!map || map->isEmpty()) {
if (increaseVectorLength(i + 1)) {
storage = m_storage;
storage->m_vector[i] = value;
++storage->m_numValuesInVector;
checkConsistency();
} else
throwOutOfMemoryError(exec);
return;
}
// Decide how many values it would be best to move from the map.
unsigned newNumValuesInVector = storage->m_numValuesInVector + 1;
unsigned newVectorLength = increasedVectorLength(i + 1);
for (unsigned j = max(m_vectorLength, MIN_SPARSE_ARRAY_INDEX); j < newVectorLength; ++j)
newNumValuesInVector += map->contains(j);
if (i >= MIN_SPARSE_ARRAY_INDEX)
newNumValuesInVector -= map->contains(i);
if (isDenseEnoughForVector(newVectorLength, newNumValuesInVector)) {
unsigned proposedNewNumValuesInVector = newNumValuesInVector;
// If newVectorLength is already the maximum - MAX_STORAGE_VECTOR_LENGTH - then do not attempt to grow any further.
while (newVectorLength < MAX_STORAGE_VECTOR_LENGTH) {
unsigned proposedNewVectorLength = increasedVectorLength(newVectorLength + 1);
for (unsigned j = max(newVectorLength, MIN_SPARSE_ARRAY_INDEX); j < proposedNewVectorLength; ++j)
proposedNewNumValuesInVector += map->contains(j);
if (!isDenseEnoughForVector(proposedNewVectorLength, proposedNewNumValuesInVector))
break;
newVectorLength = proposedNewVectorLength;
newNumValuesInVector = proposedNewNumValuesInVector;
}
}
if (!tryFastRealloc(storage, storageSize(newVectorLength)).getValue(storage)) {
throwOutOfMemoryError(exec);
return;
}
unsigned vectorLength = m_vectorLength;
if (newNumValuesInVector == storage->m_numValuesInVector + 1) {
for (unsigned j = vectorLength; j < newVectorLength; ++j)
storage->m_vector[j] = JSValue();
if (i > MIN_SPARSE_ARRAY_INDEX)
map->remove(i);
} else {
for (unsigned j = vectorLength; j < max(vectorLength, MIN_SPARSE_ARRAY_INDEX); ++j)
storage->m_vector[j] = JSValue();
for (unsigned j = max(vectorLength, MIN_SPARSE_ARRAY_INDEX); j < newVectorLength; ++j)
storage->m_vector[j] = map->take(j);
}
storage->m_vector[i] = value;
m_vectorLength = newVectorLength;
storage->m_numValuesInVector = newNumValuesInVector;
m_storage = storage;
checkConsistency();
Heap::heap(this)->reportExtraMemoryCost(storageSize(newVectorLength) - storageSize(vectorLength));
}
bool JSArray::deleteProperty(ExecState* exec, const Identifier& propertyName)
{
bool isArrayIndex;
unsigned i = propertyName.toArrayIndex(&isArrayIndex);
if (isArrayIndex)
return deleteProperty(exec, i);
if (propertyName == exec->propertyNames().length)
return false;
return JSObject::deleteProperty(exec, propertyName);
}
bool JSArray::deleteProperty(ExecState* exec, unsigned i)
{
checkConsistency();
ArrayStorage* storage = m_storage;
if (i < m_vectorLength) {
JSValue& valueSlot = storage->m_vector[i];
if (!valueSlot) {
checkConsistency();
return false;
}
valueSlot = JSValue();
--storage->m_numValuesInVector;
checkConsistency();
return true;
}
if (SparseArrayValueMap* map = storage->m_sparseValueMap) {
if (i >= MIN_SPARSE_ARRAY_INDEX) {
SparseArrayValueMap::iterator it = map->find(i);
if (it != map->end()) {
map->remove(it);
checkConsistency();
return true;
}
}
}
checkConsistency();
if (i > MAX_ARRAY_INDEX)
return deleteProperty(exec, Identifier::from(exec, i));
return false;
}
void JSArray::getOwnPropertyNames(ExecState* exec, PropertyNameArray& propertyNames, EnumerationMode mode)
{
// FIXME: Filling PropertyNameArray with an identifier for every integer
// is incredibly inefficient for large arrays. We need a different approach,
// which almost certainly means a different structure for PropertyNameArray.
ArrayStorage* storage = m_storage;
unsigned usedVectorLength = min(storage->m_length, m_vectorLength);
for (unsigned i = 0; i < usedVectorLength; ++i) {
if (storage->m_vector[i])
propertyNames.add(Identifier::from(exec, i));
}
if (SparseArrayValueMap* map = storage->m_sparseValueMap) {
SparseArrayValueMap::iterator end = map->end();
for (SparseArrayValueMap::iterator it = map->begin(); it != end; ++it)
propertyNames.add(Identifier::from(exec, it->first));
}
if (mode == IncludeDontEnumProperties)
propertyNames.add(exec->propertyNames().length);
JSObject::getOwnPropertyNames(exec, propertyNames, mode);
}
bool JSArray::increaseVectorLength(unsigned newLength)
{
// This function leaves the array in an internally inconsistent state, because it does not move any values from sparse value map
// to the vector. Callers have to account for that, because they can do it more efficiently.
ArrayStorage* storage = m_storage;
unsigned vectorLength = m_vectorLength;
ASSERT(newLength > vectorLength);
ASSERT(newLength <= MAX_STORAGE_VECTOR_INDEX);
unsigned newVectorLength = increasedVectorLength(newLength);
if (!tryFastRealloc(storage, storageSize(newVectorLength)).getValue(storage))
return false;
m_vectorLength = newVectorLength;
for (unsigned i = vectorLength; i < newVectorLength; ++i)
storage->m_vector[i] = JSValue();
m_storage = storage;
Heap::heap(this)->reportExtraMemoryCost(storageSize(newVectorLength) - storageSize(vectorLength));
return true;
}
void JSArray::setLength(unsigned newLength)
{
checkConsistency();
ArrayStorage* storage = m_storage;
unsigned length = m_storage->m_length;
if (newLength < length) {
unsigned usedVectorLength = min(length, m_vectorLength);
for (unsigned i = newLength; i < usedVectorLength; ++i) {
JSValue& valueSlot = storage->m_vector[i];
bool hadValue = valueSlot;
valueSlot = JSValue();
storage->m_numValuesInVector -= hadValue;
}
if (SparseArrayValueMap* map = storage->m_sparseValueMap) {
SparseArrayValueMap copy = *map;
SparseArrayValueMap::iterator end = copy.end();
for (SparseArrayValueMap::iterator it = copy.begin(); it != end; ++it) {
if (it->first >= newLength)
map->remove(it->first);
}
if (map->isEmpty()) {
delete map;
storage->m_sparseValueMap = 0;
}
}
}
m_storage->m_length = newLength;
checkConsistency();
}
JSValue JSArray::pop()
{
checkConsistency();
unsigned length = m_storage->m_length;
if (!length)
return jsUndefined();
--length;
JSValue result;
if (length < m_vectorLength) {
JSValue& valueSlot = m_storage->m_vector[length];
if (valueSlot) {
--m_storage->m_numValuesInVector;
result = valueSlot;
valueSlot = JSValue();
} else
result = jsUndefined();
} else {
result = jsUndefined();
if (SparseArrayValueMap* map = m_storage->m_sparseValueMap) {
SparseArrayValueMap::iterator it = map->find(length);
if (it != map->end()) {
result = it->second;
map->remove(it);
if (map->isEmpty()) {
delete map;
m_storage->m_sparseValueMap = 0;
}
}
}
}
m_storage->m_length = length;
checkConsistency();
return result;
}
void JSArray::push(ExecState* exec, JSValue value)
{
checkConsistency();
if (m_storage->m_length < m_vectorLength) {
m_storage->m_vector[m_storage->m_length] = value;
++m_storage->m_numValuesInVector;
++m_storage->m_length;
checkConsistency();
return;
}
if (m_storage->m_length < MIN_SPARSE_ARRAY_INDEX) {
SparseArrayValueMap* map = m_storage->m_sparseValueMap;
if (!map || map->isEmpty()) {
if (increaseVectorLength(m_storage->m_length + 1)) {
m_storage->m_vector[m_storage->m_length] = value;
++m_storage->m_numValuesInVector;
++m_storage->m_length;
checkConsistency();
return;
}
checkConsistency();
throwOutOfMemoryError(exec);
return;
}
}
putSlowCase(exec, m_storage->m_length++, value);
}
void JSArray::markChildren(MarkStack& markStack)
{
markChildrenDirect(markStack);
}
static int compareNumbersForQSort(const void* a, const void* b)
{
double da = static_cast<const JSValue*>(a)->uncheckedGetNumber();
double db = static_cast<const JSValue*>(b)->uncheckedGetNumber();
return (da > db) - (da < db);
}
typedef std::pair<JSValue, UString> ValueStringPair;
static int compareByStringPairForQSort(const void* a, const void* b)
{
const ValueStringPair* va = static_cast<const ValueStringPair*>(a);
const ValueStringPair* vb = static_cast<const ValueStringPair*>(b);
return compare(va->second, vb->second);
}
void JSArray::sortNumeric(ExecState* exec, JSValue compareFunction, CallType callType, const CallData& callData)
{
unsigned lengthNotIncludingUndefined = compactForSorting();
if (m_storage->m_sparseValueMap) {
throwOutOfMemoryError(exec);
return;
}
if (!lengthNotIncludingUndefined)
return;
bool allValuesAreNumbers = true;
size_t size = m_storage->m_numValuesInVector;
for (size_t i = 0; i < size; ++i) {
if (!m_storage->m_vector[i].isNumber()) {
allValuesAreNumbers = false;
break;
}
}
if (!allValuesAreNumbers)
return sort(exec, compareFunction, callType, callData);
// For numeric comparison, which is fast, qsort is faster than mergesort. We
// also don't require mergesort's stability, since there's no user visible
// side-effect from swapping the order of equal primitive values.
qsort(m_storage->m_vector, size, sizeof(JSValue), compareNumbersForQSort);
checkConsistency(SortConsistencyCheck);
}
void JSArray::sort(ExecState* exec)
{
unsigned lengthNotIncludingUndefined = compactForSorting();
if (m_storage->m_sparseValueMap) {
throwOutOfMemoryError(exec);
return;
}
if (!lengthNotIncludingUndefined)
return;
// Converting JavaScript values to strings can be expensive, so we do it once up front and sort based on that.
// This is a considerable improvement over doing it twice per comparison, though it requires a large temporary
// buffer. Besides, this protects us from crashing if some objects have custom toString methods that return
// random or otherwise changing results, effectively making compare function inconsistent.
Vector<ValueStringPair> values(lengthNotIncludingUndefined);
if (!values.begin()) {
throwOutOfMemoryError(exec);
return;
}
for (size_t i = 0; i < lengthNotIncludingUndefined; i++) {
JSValue value = m_storage->m_vector[i];
ASSERT(!value.isUndefined());
values[i].first = value;
}
// FIXME: While calling these toString functions, the array could be mutated.
// In that case, objects pointed to by values in this vector might get garbage-collected!
// FIXME: The following loop continues to call toString on subsequent values even after
// a toString call raises an exception.
for (size_t i = 0; i < lengthNotIncludingUndefined; i++)
values[i].second = values[i].first.toString(exec);
if (exec->hadException())
return;
// FIXME: Since we sort by string value, a fast algorithm might be to use a radix sort. That would be O(N) rather
// than O(N log N).
#if HAVE(MERGESORT)
mergesort(values.begin(), values.size(), sizeof(ValueStringPair), compareByStringPairForQSort);
#else
// FIXME: The qsort library function is likely to not be a stable sort.
// ECMAScript-262 does not specify a stable sort, but in practice, browsers perform a stable sort.
qsort(values.begin(), values.size(), sizeof(ValueStringPair), compareByStringPairForQSort);
#endif
// FIXME: If the toString function changed the length of the array, this might be
// modifying the vector incorrectly.
for (size_t i = 0; i < lengthNotIncludingUndefined; i++)
m_storage->m_vector[i] = values[i].first;
checkConsistency(SortConsistencyCheck);
}
struct AVLTreeNodeForArrayCompare {
JSValue value;
// Child pointers. The high bit of gt is robbed and used as the
// balance factor sign. The high bit of lt is robbed and used as
// the magnitude of the balance factor.
int32_t gt;
int32_t lt;
};
struct AVLTreeAbstractorForArrayCompare {
typedef int32_t handle; // Handle is an index into m_nodes vector.
typedef JSValue key;
typedef int32_t size;
Vector<AVLTreeNodeForArrayCompare> m_nodes;
ExecState* m_exec;
JSValue m_compareFunction;
CallType m_compareCallType;
const CallData* m_compareCallData;
JSValue m_globalThisValue;
OwnPtr<CachedCall> m_cachedCall;
handle get_less(handle h) { return m_nodes[h].lt & 0x7FFFFFFF; }
void set_less(handle h, handle lh) { m_nodes[h].lt &= 0x80000000; m_nodes[h].lt |= lh; }
handle get_greater(handle h) { return m_nodes[h].gt & 0x7FFFFFFF; }
void set_greater(handle h, handle gh) { m_nodes[h].gt &= 0x80000000; m_nodes[h].gt |= gh; }
int get_balance_factor(handle h)
{
if (m_nodes[h].gt & 0x80000000)
return -1;
return static_cast<unsigned>(m_nodes[h].lt) >> 31;
}
void set_balance_factor(handle h, int bf)
{
if (bf == 0) {
m_nodes[h].lt &= 0x7FFFFFFF;
m_nodes[h].gt &= 0x7FFFFFFF;
} else {
m_nodes[h].lt |= 0x80000000;
if (bf < 0)
m_nodes[h].gt |= 0x80000000;
else
m_nodes[h].gt &= 0x7FFFFFFF;
}
}
int compare_key_key(key va, key vb)
{
ASSERT(!va.isUndefined());
ASSERT(!vb.isUndefined());
if (m_exec->hadException())
return 1;
double compareResult;
if (m_cachedCall) {
m_cachedCall->setThis(m_globalThisValue);
m_cachedCall->setArgument(0, va);
m_cachedCall->setArgument(1, vb);
compareResult = m_cachedCall->call().toNumber(m_cachedCall->newCallFrame(m_exec));
} else {
MarkedArgumentBuffer arguments;
arguments.append(va);
arguments.append(vb);
compareResult = call(m_exec, m_compareFunction, m_compareCallType, *m_compareCallData, m_globalThisValue, arguments).toNumber(m_exec);
}
return (compareResult < 0) ? -1 : 1; // Not passing equality through, because we need to store all values, even if equivalent.
}
int compare_key_node(key k, handle h) { return compare_key_key(k, m_nodes[h].value); }
int compare_node_node(handle h1, handle h2) { return compare_key_key(m_nodes[h1].value, m_nodes[h2].value); }
static handle null() { return 0x7FFFFFFF; }
};
void JSArray::sort(ExecState* exec, JSValue compareFunction, CallType callType, const CallData& callData)
{
checkConsistency();
// FIXME: This ignores exceptions raised in the compare function or in toNumber.
// The maximum tree depth is compiled in - but the caller is clearly up to no good
// if a larger array is passed.
ASSERT(m_storage->m_length <= static_cast<unsigned>(std::numeric_limits<int>::max()));
if (m_storage->m_length > static_cast<unsigned>(std::numeric_limits<int>::max()))
return;
if (!m_storage->m_length)
return;
unsigned usedVectorLength = min(m_storage->m_length, m_vectorLength);
AVLTree<AVLTreeAbstractorForArrayCompare, 44> tree; // Depth 44 is enough for 2^31 items
tree.abstractor().m_exec = exec;
tree.abstractor().m_compareFunction = compareFunction;
tree.abstractor().m_compareCallType = callType;
tree.abstractor().m_compareCallData = &callData;
tree.abstractor().m_globalThisValue = exec->globalThisValue();
tree.abstractor().m_nodes.resize(usedVectorLength + (m_storage->m_sparseValueMap ? m_storage->m_sparseValueMap->size() : 0));
if (callType == CallTypeJS)
tree.abstractor().m_cachedCall.set(new CachedCall(exec, asFunction(compareFunction), 2, exec->exceptionSlot()));
if (!tree.abstractor().m_nodes.begin()) {
throwOutOfMemoryError(exec);
return;
}
// FIXME: If the compare function modifies the array, the vector, map, etc. could be modified
// right out from under us while we're building the tree here.
unsigned numDefined = 0;
unsigned numUndefined = 0;
// Iterate over the array, ignoring missing values, counting undefined ones, and inserting all other ones into the tree.
for (; numDefined < usedVectorLength; ++numDefined) {
JSValue v = m_storage->m_vector[numDefined];
if (!v || v.isUndefined())
break;
tree.abstractor().m_nodes[numDefined].value = v;
tree.insert(numDefined);
}
for (unsigned i = numDefined; i < usedVectorLength; ++i) {
JSValue v = m_storage->m_vector[i];
if (v) {
if (v.isUndefined())
++numUndefined;
else {
tree.abstractor().m_nodes[numDefined].value = v;
tree.insert(numDefined);
++numDefined;
}
}
}
unsigned newUsedVectorLength = numDefined + numUndefined;
if (SparseArrayValueMap* map = m_storage->m_sparseValueMap) {
newUsedVectorLength += map->size();
if (newUsedVectorLength > m_vectorLength) {
// Check that it is possible to allocate an array large enough to hold all the entries.
if ((newUsedVectorLength > MAX_STORAGE_VECTOR_LENGTH) || !increaseVectorLength(newUsedVectorLength)) {
throwOutOfMemoryError(exec);
return;
}
}
SparseArrayValueMap::iterator end = map->end();
for (SparseArrayValueMap::iterator it = map->begin(); it != end; ++it) {
tree.abstractor().m_nodes[numDefined].value = it->second;
tree.insert(numDefined);
++numDefined;
}
delete map;
m_storage->m_sparseValueMap = 0;
}
ASSERT(tree.abstractor().m_nodes.size() >= numDefined);
// FIXME: If the compare function changed the length of the array, the following might be
// modifying the vector incorrectly.
// Copy the values back into m_storage.
AVLTree<AVLTreeAbstractorForArrayCompare, 44>::Iterator iter;
iter.start_iter_least(tree);
for (unsigned i = 0; i < numDefined; ++i) {
m_storage->m_vector[i] = tree.abstractor().m_nodes[*iter].value;
++iter;
}
// Put undefined values back in.
for (unsigned i = numDefined; i < newUsedVectorLength; ++i)
m_storage->m_vector[i] = jsUndefined();
// Ensure that unused values in the vector are zeroed out.
for (unsigned i = newUsedVectorLength; i < usedVectorLength; ++i)
m_storage->m_vector[i] = JSValue();
m_storage->m_numValuesInVector = newUsedVectorLength;
checkConsistency(SortConsistencyCheck);
}
void JSArray::fillArgList(ExecState* exec, MarkedArgumentBuffer& args)
{
JSValue* vector = m_storage->m_vector;
unsigned vectorEnd = min(m_storage->m_length, m_vectorLength);
unsigned i = 0;
for (; i < vectorEnd; ++i) {
JSValue& v = vector[i];
if (!v)
break;
args.append(v);
}
for (; i < m_storage->m_length; ++i)
args.append(get(exec, i));
}
void JSArray::copyToRegisters(ExecState* exec, Register* buffer, uint32_t maxSize)
{
ASSERT(m_storage->m_length == maxSize);
UNUSED_PARAM(maxSize);
JSValue* vector = m_storage->m_vector;
unsigned vectorEnd = min(m_storage->m_length, m_vectorLength);
unsigned i = 0;
for (; i < vectorEnd; ++i) {
JSValue& v = vector[i];
if (!v)
break;
buffer[i] = v;
}
for (; i < m_storage->m_length; ++i)
buffer[i] = get(exec, i);
}
unsigned JSArray::compactForSorting()
{
checkConsistency();
ArrayStorage* storage = m_storage;
unsigned usedVectorLength = min(m_storage->m_length, m_vectorLength);
unsigned numDefined = 0;
unsigned numUndefined = 0;
for (; numDefined < usedVectorLength; ++numDefined) {
JSValue v = storage->m_vector[numDefined];
if (!v || v.isUndefined())
break;
}
for (unsigned i = numDefined; i < usedVectorLength; ++i) {
JSValue v = storage->m_vector[i];
if (v) {
if (v.isUndefined())
++numUndefined;
else
storage->m_vector[numDefined++] = v;
}
}
unsigned newUsedVectorLength = numDefined + numUndefined;
if (SparseArrayValueMap* map = storage->m_sparseValueMap) {
newUsedVectorLength += map->size();
if (newUsedVectorLength > m_vectorLength) {
// Check that it is possible to allocate an array large enough to hold all the entries - if not,
// exception is thrown by caller.
if ((newUsedVectorLength > MAX_STORAGE_VECTOR_LENGTH) || !increaseVectorLength(newUsedVectorLength))
return 0;
storage = m_storage;
}
SparseArrayValueMap::iterator end = map->end();
for (SparseArrayValueMap::iterator it = map->begin(); it != end; ++it)
storage->m_vector[numDefined++] = it->second;
delete map;
storage->m_sparseValueMap = 0;
}
for (unsigned i = numDefined; i < newUsedVectorLength; ++i)
storage->m_vector[i] = jsUndefined();
for (unsigned i = newUsedVectorLength; i < usedVectorLength; ++i)
storage->m_vector[i] = JSValue();
storage->m_numValuesInVector = newUsedVectorLength;
checkConsistency(SortConsistencyCheck);
return numDefined;
}
void* JSArray::lazyCreationData()
{
return m_storage->lazyCreationData;
}
void JSArray::setLazyCreationData(void* d)
{
m_storage->lazyCreationData = d;
}
#if CHECK_ARRAY_CONSISTENCY
void JSArray::checkConsistency(ConsistencyCheckType type)
{
ASSERT(m_storage);
if (type == SortConsistencyCheck)
ASSERT(!m_storage->m_sparseValueMap);
unsigned numValuesInVector = 0;
for (unsigned i = 0; i < m_vectorLength; ++i) {
if (JSValue value = m_storage->m_vector[i]) {
ASSERT(i < m_storage->m_length);
if (type != DestructorConsistencyCheck)
value->type(); // Likely to crash if the object was deallocated.
++numValuesInVector;
} else {
if (type == SortConsistencyCheck)
ASSERT(i >= m_storage->m_numValuesInVector);
}
}
ASSERT(numValuesInVector == m_storage->m_numValuesInVector);
ASSERT(numValuesInVector <= m_storage->m_length);
if (m_storage->m_sparseValueMap) {
SparseArrayValueMap::iterator end = m_storage->m_sparseValueMap->end();
for (SparseArrayValueMap::iterator it = m_storage->m_sparseValueMap->begin(); it != end; ++it) {
unsigned index = it->first;
ASSERT(index < m_storage->m_length);
ASSERT(index >= m_vectorLength);
ASSERT(index <= MAX_ARRAY_INDEX);
ASSERT(it->second);
if (type != DestructorConsistencyCheck)
it->second->type(); // Likely to crash if the object was deallocated.
}
}
}
#endif
} // namespace JSC