arkcompiler_ets_runtime/ecmascript/linked_hash_table.h
xusen 98d182ffff Ason.parse support map
Ason.parse support map

Issue:       https://gitee.com/openharmony/arkcompiler_ets_runtime/issues/IAE0IJ
Signed-off-by: xusen <xusen15@huawei.com>
2024-08-04 10:38:56 +08:00

412 lines
15 KiB
C++

/*
* Copyright (c) 2021 Huawei Device Co., Ltd.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ECMASCRIPT_LINKED_HASH_TABLE_H
#define ECMASCRIPT_LINKED_HASH_TABLE_H
#include "ecmascript/js_tagged_value.h"
#include "ecmascript/js_handle.h"
#include "ecmascript/js_symbol.h"
#include "ecmascript/js_tagged_number.h"
#include "ecmascript/tagged_array-inl.h"
namespace panda::ecmascript {
class LinkedHash {
public:
static int Hash(const JSThread *thread, JSTaggedValue key);
};
/**
* memory in LinkedHashTable is divided into 3 parts
* 1.array[0-2] is used to store common information of hashtale such as numberOfElements and capacity
* 2.array[3,3+capacity] is buckets which store the position of entry
* 3.array[3+capacity+1,3+capacity + capacity*(entry_size+1)] is the entry stored in order, the last element of an entry
* is a number which point to next entry.
* */
template<typename Derived, typename HashObject>
class LinkedHashTable : public TaggedArray {
public:
static const int MIN_CAPACITY = 4;
static const int NUMBER_OF_ELEMENTS_INDEX = 0;
static const int NUMBER_OF_DELETED_ELEMENTS_INDEX = 1;
static const int CAPACITY_INDEX = 2;
static const int NEXT_TABLE_INDEX = 3;
static const int ELEMENTS_START_INDEX = 4;
// Don't shrink a HashTable below this capacity.
static const int MIN_SHRINK_CAPACITY = 16;
static JSHandle<Derived> Create(const JSThread *thread, int numberOfElements, MemSpaceKind spaceKind);
static JSHandle<Derived> Insert(const JSThread *thread, const JSHandle<Derived> &table,
const JSHandle<JSTaggedValue> &key, const JSHandle<JSTaggedValue> &value);
static JSHandle<Derived> InsertWeakRef(const JSThread *thread, const JSHandle<Derived> &table,
const JSHandle<JSTaggedValue> &key, const JSHandle<JSTaggedValue> &value);
static JSHandle<Derived> GrowCapacity(const JSThread *thread, const JSHandle<Derived> &table,
int numberOfAddedElements = 1);
static JSHandle<Derived> Remove(const JSThread *thread, const JSHandle<Derived> &table,
const JSHandle<JSTaggedValue> &key);
static JSHandle<Derived> Shrink(const JSThread *thread, const JSHandle<Derived> &table, int additionalCapacity = 0);
static int GetLengthOfTable(int numberOfElements)
{
return ELEMENTS_START_INDEX + numberOfElements + numberOfElements * (HashObject::ENTRY_SIZE + 1);
}
inline bool HasSufficientCapacity(int numOfAddElements) const
{
int numberOfElements = NumberOfElements();
int numOfDelElements = NumberOfDeletedElements();
int capacity = Capacity();
int nof = numberOfElements + numOfAddElements;
// Return true if:
// 50% is still free after adding numOfAddElements elements and
// at most 50% of the free elements are deleted elements.
if ((nof < capacity) && ((numOfDelElements <= (capacity - nof) / 2))) { // 2: half
int neededFree = nof / 2; // 2: half
if (nof + neededFree <= capacity) {
return true;
}
}
return false;
}
inline int FindElement(const JSThread *thread, JSTaggedValue key) const
{
if (!IsKey(key)) {
return -1;
}
int hash = LinkedHash::Hash(thread, key);
uint32_t bucket = HashToBucket(hash);
for (JSTaggedValue entry = GetElement(BucketToIndex(bucket)); !entry.IsHole();
entry = GetNextEntry(entry.GetInt())) {
JSTaggedValue element = GetKey(entry.GetInt());
if (element.IsHole()) {
continue;
}
if (element.IsWeak()) {
element.RemoveWeakTag();
}
if (HashObject::IsMatch(key, element)) {
return entry.GetInt();
}
}
return -1;
}
inline void RemoveEntry(const JSThread *thread, int entry)
{
ASSERT_PRINT(entry >= 0 && entry < Capacity(), "entry must be a non-negative integer less than capacity");
int index = static_cast<int>(EntryToIndex(entry));
for (int i = 0; i < HashObject::ENTRY_SIZE; i++) {
SetElement(thread, index + i, JSTaggedValue::Hole());
}
SetNumberOfElements(thread, NumberOfElements() - 1);
SetNumberOfDeletedElements(thread, NumberOfDeletedElements() + 1);
}
inline static int ComputeCapacity(uint32_t atLeastSpaceFor)
{
// Add 50% slack to make slot collisions sufficiently unlikely.
// See matching computation in HashTable::HasSufficientCapacity().
uint32_t rawCap = atLeastSpaceFor + (atLeastSpaceFor >> 1UL);
int capacity = static_cast<int>(helpers::math::GetPowerOfTwoValue32(rawCap));
return (capacity > MIN_CAPACITY) ? capacity : MIN_CAPACITY;
}
inline static int ComputeCapacityWithShrink(int currentCapacity, int atLeastSpaceFor)
{
// Shrink to fit the number of elements if only a quarter of the
// capacity is filled with elements.
if (atLeastSpaceFor > (currentCapacity / 4)) { // 4: quarter
return currentCapacity;
}
// Recalculate the smaller capacity actually needed.
int newCapacity = ComputeCapacity(atLeastSpaceFor);
ASSERT_PRINT(newCapacity > atLeastSpaceFor, "new capacity must greater than atLeastSpaceFor");
// Don't go lower than room for MIN_SHRINK_CAPACITY elements.
if (newCapacity < Derived::MIN_SHRINK_CAPACITY) {
return currentCapacity;
}
return newCapacity;
}
inline int NumberOfElements() const
{
return Get(NUMBER_OF_ELEMENTS_INDEX).GetInt();
}
inline int NumberOfDeletedElements() const
{
return Get(NUMBER_OF_DELETED_ELEMENTS_INDEX).GetInt();
}
inline int Capacity() const
{
return JSTaggedValue(Get(CAPACITY_INDEX)).GetInt();
}
inline JSTaggedValue GetKey(int entry) const
{
int index = static_cast<int>(EntryToIndex(entry));
return GetElement(index);
}
inline JSTaggedValue GetValue(int entry) const
{
int index = static_cast<int>(EntryToIndex(entry)) + HashObject::ENTRY_VALUE_INDEX;
return GetElement(index);
}
inline static bool IsKey(JSTaggedValue key)
{
return !key.IsHole();
}
inline void SetNumberOfElements(const JSThread *thread, int nof)
{
Set(thread, NUMBER_OF_ELEMENTS_INDEX, JSTaggedValue(nof));
}
inline void SetNumberOfDeletedElements(const JSThread *thread, int nod)
{
Set(thread, NUMBER_OF_DELETED_ELEMENTS_INDEX, JSTaggedValue(nod));
}
inline void SetCapacity(const JSThread *thread, int capacity)
{
Set(thread, CAPACITY_INDEX, JSTaggedValue(capacity));
}
inline JSTaggedValue GetNextTable() const
{
return JSTaggedValue(Get(NEXT_TABLE_INDEX));
}
inline void SetNextTable(const JSThread *thread, JSTaggedValue nextTable)
{
Set(thread, NEXT_TABLE_INDEX, nextTable);
}
inline int GetDeletedElementsAt(int entry) const
{
ASSERT_PRINT(!GetNextTable().IsUndefined(), "function only execute after rehash");
int currentEntry = entry - 1;
if (NumberOfDeletedElements() == -1) {
return entry;
}
while (currentEntry >= 0) {
if (GetKey(currentEntry).IsHole()) {
return GetDeletedNum(currentEntry);
}
currentEntry--;
}
return 0;
}
inline void Rehash(const JSThread *thread, Derived *newTable)
{
ASSERT_PRINT(newTable != nullptr && newTable->Capacity() > NumberOfElements(), "can not rehash to new table");
// Rehash elements to new table
int numberOfAllElements = NumberOfElements() + NumberOfDeletedElements();
int desEntry = 0;
int currentDeletedElements = 0;
SetNextTable(thread, JSTaggedValue(newTable));
for (int i = 0; i < numberOfAllElements; i++) {
int fromIndex = static_cast<int>(EntryToIndex(i));
JSTaggedValue key = GetElement(fromIndex);
if (key.IsHole()) {
// store num_of_deleted_element before entry i; it will be used when iterator update.
currentDeletedElements++;
SetDeletedNum(thread, i, JSTaggedValue(currentDeletedElements));
continue;
}
if (key.IsWeak()) {
// If the key is a weak reference, we use the weak referent to calculate the new index in the new table.
key.RemoveWeakTag();
}
int bucket = static_cast<int>(newTable->HashToBucket(LinkedHash::Hash(thread, key)));
newTable->InsertNewEntry(thread, bucket, desEntry);
int desIndex = static_cast<int>(newTable->EntryToIndex(desEntry));
for (int j = 0; j < HashObject::ENTRY_SIZE; j++) {
newTable->SetElement(thread, desIndex + j, GetElement(fromIndex + j));
}
desEntry++;
}
newTable->SetNumberOfElements(thread, NumberOfElements());
newTable->SetNumberOfDeletedElements(thread, 0);
}
protected:
inline JSTaggedValue GetElement(int index) const
{
ASSERT(index >= 0 && index < static_cast<int>(GetLength()));
return Get(index);
}
inline void SetElement(const JSThread *thread, int index, JSTaggedValue element)
{
ASSERT(index >= 0 && index < static_cast<int>(GetLength()));
Set(thread, index, element);
}
inline void SetKey(const JSThread *thread, int entry, JSTaggedValue key)
{
int index = static_cast<int>(EntryToIndex(entry));
SetElement(thread, index, key);
}
inline void SetValue(const JSThread *thread, int entry, JSTaggedValue value)
{
int index = static_cast<int>(EntryToIndex(entry)) + HashObject::ENTRY_VALUE_INDEX;
SetElement(thread, index, value);
}
inline JSTaggedValue GetNextEntry(int entry) const
{
int index = static_cast<int>(EntryToIndex(entry)) + HashObject::ENTRY_SIZE;
return GetElement(index);
}
inline void SetNextEntry(const JSThread *thread, int entry, JSTaggedValue nextEntry)
{
int index = static_cast<int>(EntryToIndex(entry)) + HashObject::ENTRY_SIZE;
SetElement(thread, index, nextEntry);
}
inline uint32_t HashToBucket(uint32_t hash) const
{
return hash & static_cast<uint32_t>(Capacity() - 1);
}
inline static uint32_t BucketToIndex(uint32_t bucket)
{
return bucket + ELEMENTS_START_INDEX;
}
// min entry = 0
inline uint32_t EntryToIndex(uint32_t entry) const
{
return ELEMENTS_START_INDEX + Capacity() + static_cast<int>(entry) * (HashObject::ENTRY_SIZE + 1);
}
inline void InsertNewEntry(const JSThread *thread, int bucket, int entry)
{
int bucketIndex = static_cast<int>(BucketToIndex(bucket));
JSTaggedValue previousEntry = GetElement(bucketIndex);
SetNextEntry(thread, entry, previousEntry);
SetElement(thread, bucketIndex, JSTaggedValue(entry));
}
inline int GetDeletedNum(int entry) const
{
ASSERT_PRINT(!GetNextTable().IsUndefined(), "function only execute after rehash");
return GetNextEntry(entry).GetInt();
}
inline void SetDeletedNum(const JSThread *thread, int entry, JSTaggedValue num)
{
ASSERT_PRINT(!GetNextTable().IsUndefined(), "function only execute after rehash");
SetNextEntry(thread, entry, num);
}
};
class LinkedHashMapObject {
public:
// key must be string now for other object has no 'equals' method
static inline bool IsMatch(JSTaggedValue key, JSTaggedValue other)
{
return JSTaggedValue::SameValueZero(key, other);
}
static const int ENTRY_SIZE = 2;
static const int ENTRY_VALUE_INDEX = 1;
};
class LinkedHashMap : public LinkedHashTable<LinkedHashMap, LinkedHashMapObject> {
public:
static LinkedHashMap *Cast(TaggedObject *obj)
{
return static_cast<LinkedHashMap *>(obj);
}
static JSHandle<LinkedHashMap> PUBLIC_API Create(const JSThread *thread, int numberOfElements = MIN_CAPACITY,
MemSpaceKind spaceKind = MemSpaceKind::LOCAL);
static JSHandle<LinkedHashMap> Delete(const JSThread *thread, const JSHandle<LinkedHashMap> &obj,
const JSHandle<JSTaggedValue> &key);
static JSHandle<LinkedHashMap> Set(const JSThread *thread, const JSHandle<LinkedHashMap> &obj,
const JSHandle<JSTaggedValue> &key, const JSHandle<JSTaggedValue> &value);
static JSHandle<LinkedHashMap> SetWeakRef(const JSThread *thread, const JSHandle<LinkedHashMap> &obj,
const JSHandle<JSTaggedValue> &key, const JSHandle<JSTaggedValue> &value);
JSTaggedValue Get(const JSThread *thread, JSTaggedValue key) const;
static JSHandle<LinkedHashMap> Shrink(const JSThread *thread, const JSHandle<LinkedHashMap> &table,
int additionalCapacity = 0);
bool Has(const JSThread *thread, JSTaggedValue key) const;
static JSHandle<LinkedHashMap> Clear(const JSThread *thread, const JSHandle<LinkedHashMap> &table);
DECL_DUMP()
};
class LinkedHashSetObject {
public:
// key must be string now for other object has no 'equals' method
static inline bool IsMatch(JSTaggedValue key, JSTaggedValue other)
{
return JSTaggedValue::SameValueZero(key, other);
}
static const int ENTRY_SIZE = 1;
static const int ENTRY_VALUE_INDEX = 0;
};
class LinkedHashSet : public LinkedHashTable<LinkedHashSet, LinkedHashSetObject> {
public:
static LinkedHashSet *Cast(TaggedObject *obj)
{
return static_cast<LinkedHashSet *>(obj);
}
static JSHandle<LinkedHashSet> Create(const JSThread *thread, int numberOfElements = MIN_CAPACITY,
MemSpaceKind spaceKind = MemSpaceKind::LOCAL);
static JSHandle<LinkedHashSet> Delete(const JSThread *thread, const JSHandle<LinkedHashSet> &obj,
const JSHandle<JSTaggedValue> &key);
static JSHandle<LinkedHashSet> Add(const JSThread *thread, const JSHandle<LinkedHashSet> &obj,
const JSHandle<JSTaggedValue> &key);
static JSHandle<LinkedHashSet> AddWeakRef(const JSThread *thread, const JSHandle<LinkedHashSet> &obj,
const JSHandle<JSTaggedValue> &key);
static JSHandle<LinkedHashSet> Shrink(const JSThread *thread, const JSHandle<LinkedHashSet> &table,
int additionalCapacity = 0);
bool Has(const JSThread *thread, JSTaggedValue key) const;
static JSHandle<LinkedHashSet> Clear(const JSThread *thread, const JSHandle<LinkedHashSet> &table);
DECL_DUMP()
};
} // namespace panda::ecmascript
#endif // ECMASCRIPT_LINKED_HASH_TABLE_H