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 
26 namespace panda::ecmascript {
27 class EcmaVM;
28 class PropertiesCache {
29 public:
Get(JSHClass *jsHclass, JSTaggedValue key)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     }
Set(JSHClass *jsHclass, JSTaggedValue key, int index)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     }
Clear()47     inline void Clear()
48     {
49         for (auto &key : keys_) {
50             key.hclass_ = nullptr;
51             key.key_ = JSTaggedValue::Hole();
52         }
53     }
IsCleared() const54     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         };
GetHclassOffsetpanda::ecmascript::PropertiesCache::PropertyKey78         static size_t GetHclassOffset(bool isArch32 = false)
79         {
80             return GetOffset<static_cast<size_t>(Index::HclassIndex)>(isArch32);
81         }
82 
GetKeyOffsetpanda::ecmascript::PropertiesCache::PropertyKey83         static size_t GetKeyOffset(bool isArch32 = false)
84         {
85             return GetOffset<static_cast<size_t>(Index::KeyIndex)>(isArch32);
86         }
87 
GetResultsOffsetpanda::ecmascript::PropertiesCache::PropertyKey88         static size_t GetResultsOffset(bool isArch32 = false)
89         {
90             return GetOffset<static_cast<size_t>(Index::ResultsIndex)>(isArch32);
91         }
92 
GetPropertyKeySizepanda::ecmascript::PropertiesCache::PropertyKey93         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 
104 private:
PropertiesCache()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 
Hash(JSHClass *cls, JSTaggedValue key)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