1 /*
2 * Copyright (c) 2021 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 #include "ecmascript/ecma_string_table.h"
17
18 #include "ecmascript/ecma_string-inl.h"
19 #include "ecmascript/ecma_vm.h"
20 #include "ecmascript/js_thread.h"
21 #include "ecmascript/mem/c_string.h"
22 #include "ecmascript/object_factory.h"
23
24 namespace panda::ecmascript {
EcmaStringTable(const EcmaVM * vm)25 EcmaStringTable::EcmaStringTable(const EcmaVM *vm) : vm_(vm) {}
26
GetString(const JSHandle<EcmaString> & firstString,const JSHandle<EcmaString> & secondString) const27 EcmaString *EcmaStringTable::GetString(const JSHandle<EcmaString> &firstString,
28 const JSHandle<EcmaString> &secondString) const
29 {
30 uint32_t hashCode = firstString->GetHashcode();
31 hashCode = secondString->ComputeHashcode(hashCode);
32 auto range = table_.equal_range(hashCode);
33 auto item = range.first;
34 for (; item != range.second; ++item) {
35 auto foundString = item->second;
36 if (foundString->EqualToSplicedString(*firstString, *secondString)) {
37 return foundString;
38 }
39 }
40 return nullptr;
41 }
42
GetString(const uint8_t * utf8Data,uint32_t utf8Len,bool canBeCompress) const43 EcmaString *EcmaStringTable::GetString(const uint8_t *utf8Data, uint32_t utf8Len, bool canBeCompress) const
44 {
45 uint32_t hashCode = EcmaString::ComputeHashcodeUtf8(utf8Data, utf8Len, canBeCompress);
46 auto range = table_.equal_range(hashCode);
47 auto item = range.first;
48 for (; item != range.second; ++item) {
49 auto foundString = item->second;
50 if (EcmaString::StringsAreEqualUtf8(foundString, utf8Data, utf8Len, canBeCompress)) {
51 return foundString;
52 }
53 }
54 return nullptr;
55 }
56
GetString(const uint16_t * utf16Data,uint32_t utf16Len) const57 EcmaString *EcmaStringTable::GetString(const uint16_t *utf16Data, uint32_t utf16Len) const
58 {
59 uint32_t hashCode = EcmaString::ComputeHashcodeUtf16(const_cast<uint16_t *>(utf16Data), utf16Len);
60 auto range = table_.equal_range(hashCode);
61 auto item = range.first;
62 for (; item != range.second; ++item) {
63 auto foundString = item->second;
64 if (EcmaString::StringsAreEqualUtf16(foundString, utf16Data, utf16Len)) {
65 return foundString;
66 }
67 }
68 return nullptr;
69 }
70
GetString(EcmaString * string) const71 EcmaString *EcmaStringTable::GetString(EcmaString *string) const
72 {
73 auto range = table_.equal_range(string->GetHashcode());
74 auto item = range.first;
75 for (; item != range.second; ++item) {
76 auto foundString = item->second;
77 if (EcmaString::StringsAreEqual(foundString, string)) {
78 return foundString;
79 }
80 }
81 return nullptr;
82 }
83
InternString(EcmaString * string)84 void EcmaStringTable::InternString(EcmaString *string)
85 {
86 if (string->IsInternString()) {
87 return;
88 }
89 table_.insert(std::pair<uint32_t, EcmaString *>(string->GetHashcode(), string));
90 string->SetIsInternString();
91 }
92
InternEmptyString(EcmaString * emptyStr)93 void EcmaStringTable::InternEmptyString(EcmaString *emptyStr)
94 {
95 InternString(emptyStr);
96 }
97
GetOrInternString(const JSHandle<EcmaString> & firstString,const JSHandle<EcmaString> & secondString)98 EcmaString *EcmaStringTable::GetOrInternString(const JSHandle<EcmaString> &firstString,
99 const JSHandle<EcmaString> &secondString)
100 {
101 EcmaString *concatString = GetString(firstString, secondString);
102 if (concatString != nullptr) {
103 return concatString;
104 }
105
106 concatString = EcmaString::Concat(firstString, secondString, vm_);
107
108 InternString(concatString);
109 return concatString;
110 }
111
GetOrInternString(const uint8_t * utf8Data,uint32_t utf8Len,bool canBeCompress)112 EcmaString *EcmaStringTable::GetOrInternString(const uint8_t *utf8Data, uint32_t utf8Len, bool canBeCompress)
113 {
114 EcmaString *result = GetString(utf8Data, utf8Len, canBeCompress);
115 if (result != nullptr) {
116 return result;
117 }
118
119 result = EcmaString::CreateFromUtf8(utf8Data, utf8Len, vm_, canBeCompress);
120 InternString(result);
121 return result;
122 }
123
GetOrInternString(const uint16_t * utf16Data,uint32_t utf16Len,bool canBeCompress)124 EcmaString *EcmaStringTable::GetOrInternString(const uint16_t *utf16Data, uint32_t utf16Len, bool canBeCompress)
125 {
126 EcmaString *result = GetString(utf16Data, utf16Len);
127 if (result != nullptr) {
128 return result;
129 }
130
131 result = EcmaString::CreateFromUtf16(utf16Data, utf16Len, vm_, canBeCompress);
132 InternString(result);
133 return result;
134 }
135
GetOrInternString(EcmaString * string)136 EcmaString *EcmaStringTable::GetOrInternString(EcmaString *string)
137 {
138 if (string->IsInternString()) {
139 return string;
140 }
141
142 EcmaString *result = GetString(string);
143 if (result != nullptr) {
144 return result;
145 }
146 InternString(string);
147 return string;
148 }
149
SweepWeakReference(const WeakRootVisitor & visitor)150 void EcmaStringTable::SweepWeakReference(const WeakRootVisitor &visitor)
151 {
152 for (auto it = table_.begin(); it != table_.end();) {
153 auto *object = it->second;
154 auto fwd = visitor(object);
155 if (fwd == nullptr) {
156 LOG(DEBUG, GC) << "StringTable: delete string " << std::hex << object
157 << ", val = " << ConvertToString(object);
158 table_.erase(it++);
159 } else if (fwd != object) {
160 it->second = static_cast<EcmaString *>(fwd);
161 ++it;
162 LOG(DEBUG, GC) << "StringTable: forward " << std::hex << object << " -> " << fwd;
163 } else {
164 ++it;
165 }
166 }
167 }
168 } // namespace panda::ecmascript
169