1/*
2 * Copyright (c) 2021-2024 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 *     http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16#ifndef ECMASCRIPT_IC_PROPERTIES_CACHE_H
17#define ECMASCRIPT_IC_PROPERTIES_CACHE_H
18
19#include <array>
20
21#include "ecmascript/js_hclass.h"
22#include "ecmascript/js_tagged_value.h"
23#include "ecmascript/js_tagged_value-inl.h"
24#include "ecmascript/ecma_macros.h"
25
26namespace panda::ecmascript {
27class EcmaVM;
28class PropertiesCache {
29public:
30    inline int Get(JSHClass *jsHclass, JSTaggedValue key)
31    {
32        int hash = Hash(jsHclass, key);
33        PropertyKey &prop = keys_[hash];
34        if ((prop.hclass_ == jsHclass) && (prop.key_ == key)) {
35            return keys_[hash].results_;
36        }
37        return NOT_FOUND;
38    }
39    inline void Set(JSHClass *jsHclass, JSTaggedValue key, int index)
40    {
41        int hash = Hash(jsHclass, key);
42        PropertyKey &prop = keys_[hash];
43        prop.hclass_ = jsHclass;
44        prop.key_ = key;
45        keys_[hash].results_ = index;
46    }
47    inline void Clear()
48    {
49        for (auto &key : keys_) {
50            key.hclass_ = nullptr;
51            key.key_ = JSTaggedValue::Hole();
52        }
53    }
54    inline bool IsCleared() const
55    {
56        for (auto &key : keys_) {
57            if (key.hclass_ != nullptr) {
58                return false;
59            }
60        }
61        return true;
62    }
63    static const int NOT_FOUND = -1;
64    static const uint32_t CACHE_LENGTH_BIT = 10;
65    static const uint32_t CACHE_LENGTH = (1U << CACHE_LENGTH_BIT);
66    static const uint32_t CACHE_LENGTH_MASK = CACHE_LENGTH - 1;
67
68    struct PropertyKey : public base::AlignedStruct<JSTaggedValue::TaggedTypeSize(),
69                                                    base::AlignedPointer,
70                                                    JSTaggedValue,
71                                                    base::AlignedUint32> {
72        enum class Index : size_t {
73            HclassIndex = 0,
74            KeyIndex,
75            ResultsIndex,
76            NumOfMembers
77        };
78        static size_t GetHclassOffset(bool isArch32 = false)
79        {
80            return GetOffset<static_cast<size_t>(Index::HclassIndex)>(isArch32);
81        }
82
83        static size_t GetKeyOffset(bool isArch32 = false)
84        {
85            return GetOffset<static_cast<size_t>(Index::KeyIndex)>(isArch32);
86        }
87
88        static size_t GetResultsOffset(bool isArch32 = false)
89        {
90            return GetOffset<static_cast<size_t>(Index::ResultsIndex)>(isArch32);
91        }
92
93        static size_t GetPropertyKeySize()
94        {
95            return static_cast<size_t>(Index::NumOfMembers) * static_cast<size_t>(JSTaggedValue::TaggedTypeSize());
96        }
97
98        static_assert(static_cast<size_t>(Index::NumOfMembers) == NumOfTypes);
99        alignas(EAS) JSHClass *hclass_ {nullptr};
100        alignas(EAS) JSTaggedValue key_ {JSTaggedValue::Hole()};
101        alignas(EAS) int results_ {NOT_FOUND};
102    };
103
104private:
105    PropertiesCache()
106    {
107        for (uint32_t i = 0; i < CACHE_LENGTH; ++i) {
108            keys_[i].hclass_ = nullptr;
109            keys_[i].key_ = JSTaggedValue::Hole();
110            keys_[i].results_ = NOT_FOUND;
111        }
112    }
113    ~PropertiesCache() = default;
114
115    // NOLINTNEXTLINE(cppcoreguidelines-pro-type-member-init)
116
117    static inline int Hash(JSHClass *cls, JSTaggedValue key)
118    {
119        uint32_t clsHash = static_cast<uint32_t>(reinterpret_cast<uintptr_t>(cls)) >> 3U;  // skip 8bytes
120        uint32_t keyHash = key.GetKeyHashCode();
121        return static_cast<int>((clsHash ^ keyHash) & CACHE_LENGTH_MASK);
122    }
123
124    std::array<PropertyKey, CACHE_LENGTH> keys_{};
125
126    friend class EcmaContext;
127};
128}  // namespace panda::ecmascript
129#endif  // ECMASCRIPT_IC_PROPERTIES_CACHE_H
130