1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
|
/*
* Copyright (C) 2013 The Android Open Source Project
*
* 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 ART_RUNTIME_MAPPING_TABLE_H_
#define ART_RUNTIME_MAPPING_TABLE_H_
#include "base/leb128.h"
#include "base/logging.h"
namespace art {
// A utility for processing the raw uleb128 encoded mapping table created by the quick compiler.
class MappingTable {
public:
explicit MappingTable(const uint8_t* encoded_map) : encoded_table_(encoded_map) {
}
uint32_t TotalSize() const PURE {
const uint8_t* table = encoded_table_;
if (table == nullptr) {
return 0;
} else {
return DecodeUnsignedLeb128(&table);
}
}
uint32_t DexToPcSize() const PURE {
const uint8_t* table = encoded_table_;
if (table == nullptr) {
return 0;
} else {
uint32_t total_size = DecodeUnsignedLeb128(&table);
uint32_t pc_to_dex_size = DecodeUnsignedLeb128(&table);
return total_size - pc_to_dex_size;
}
}
const uint8_t* FirstDexToPcPtr() const {
const uint8_t* table = encoded_table_;
if (table != nullptr) {
uint32_t total_size = DecodeUnsignedLeb128(&table);
uint32_t pc_to_dex_size = DecodeUnsignedLeb128(&table);
// We must have dex to pc entries or else the loop will go beyond the end of the table.
DCHECK_GT(total_size, pc_to_dex_size);
for (uint32_t i = 0; i < pc_to_dex_size; ++i) {
DecodeUnsignedLeb128(&table); // Move ptr past native PC delta.
DecodeSignedLeb128(&table); // Move ptr past dex PC delta.
}
}
return table;
}
class DexToPcIterator {
public:
DexToPcIterator(const MappingTable* table, uint32_t element) :
table_(table), element_(element), end_(table_->DexToPcSize()), encoded_table_ptr_(nullptr),
native_pc_offset_(0), dex_pc_(0) {
if (element == 0) { // An iterator wanted from the start.
if (end_ > 0) {
encoded_table_ptr_ = table_->FirstDexToPcPtr();
native_pc_offset_ = DecodeUnsignedLeb128(&encoded_table_ptr_);
// First delta is always positive.
dex_pc_ = static_cast<uint32_t>(DecodeSignedLeb128(&encoded_table_ptr_));
}
} else { // An iterator wanted from the end.
DCHECK_EQ(table_->DexToPcSize(), element);
}
}
uint32_t NativePcOffset() const {
return native_pc_offset_;
}
uint32_t DexPc() const {
return dex_pc_;
}
void operator++() {
++element_;
if (element_ != end_) { // Avoid reading beyond the end of the table.
native_pc_offset_ += DecodeUnsignedLeb128(&encoded_table_ptr_);
// For negative delta, unsigned overflow after static_cast does exactly what we need.
dex_pc_ += static_cast<uint32_t>(DecodeSignedLeb128(&encoded_table_ptr_));
}
}
bool operator==(const DexToPcIterator& rhs) const {
CHECK(table_ == rhs.table_);
return element_ == rhs.element_;
}
bool operator!=(const DexToPcIterator& rhs) const {
CHECK(table_ == rhs.table_);
return element_ != rhs.element_;
}
private:
const MappingTable* const table_; // The original table.
uint32_t element_; // A value in the range 0 to end_.
const uint32_t end_; // Equal to table_->DexToPcSize().
const uint8_t* encoded_table_ptr_; // Either null or points to encoded data after this entry.
uint32_t native_pc_offset_; // The current value of native pc offset.
uint32_t dex_pc_; // The current value of dex pc.
};
DexToPcIterator DexToPcBegin() const {
return DexToPcIterator(this, 0);
}
DexToPcIterator DexToPcEnd() const {
uint32_t size = DexToPcSize();
return DexToPcIterator(this, size);
}
uint32_t PcToDexSize() const PURE {
const uint8_t* table = encoded_table_;
if (table == nullptr) {
return 0;
} else {
DecodeUnsignedLeb128(&table); // Total_size, unused.
uint32_t pc_to_dex_size = DecodeUnsignedLeb128(&table);
return pc_to_dex_size;
}
}
const uint8_t* FirstPcToDexPtr() const {
const uint8_t* table = encoded_table_;
if (table != nullptr) {
DecodeUnsignedLeb128(&table); // Total_size, unused.
DecodeUnsignedLeb128(&table); // PC to Dex size, unused.
}
return table;
}
class PcToDexIterator {
public:
PcToDexIterator(const MappingTable* table, uint32_t element) :
table_(table), element_(element), end_(table_->PcToDexSize()), encoded_table_ptr_(nullptr),
native_pc_offset_(0), dex_pc_(0) {
if (element == 0) { // An iterator wanted from the start.
if (end_ > 0) {
encoded_table_ptr_ = table_->FirstPcToDexPtr();
native_pc_offset_ = DecodeUnsignedLeb128(&encoded_table_ptr_);
// First delta is always positive.
dex_pc_ = static_cast<uint32_t>(DecodeSignedLeb128(&encoded_table_ptr_));
}
} else { // An iterator wanted from the end.
DCHECK_EQ(table_->PcToDexSize(), element);
}
}
uint32_t NativePcOffset() const {
return native_pc_offset_;
}
uint32_t DexPc() const {
return dex_pc_;
}
void operator++() {
++element_;
if (element_ != end_) { // Avoid reading beyond the end of the table.
native_pc_offset_ += DecodeUnsignedLeb128(&encoded_table_ptr_);
// For negative delta, unsigned overflow after static_cast does exactly what we need.
dex_pc_ += static_cast<uint32_t>(DecodeSignedLeb128(&encoded_table_ptr_));
}
}
bool operator==(const PcToDexIterator& rhs) const {
CHECK(table_ == rhs.table_);
return element_ == rhs.element_;
}
bool operator!=(const PcToDexIterator& rhs) const {
CHECK(table_ == rhs.table_);
return element_ != rhs.element_;
}
private:
const MappingTable* const table_; // The original table.
uint32_t element_; // A value in the range 0 to PcToDexSize.
const uint32_t end_; // Equal to table_->PcToDexSize().
const uint8_t* encoded_table_ptr_; // Either null or points to encoded data after this entry.
uint32_t native_pc_offset_; // The current value of native pc offset.
uint32_t dex_pc_; // The current value of dex pc.
};
PcToDexIterator PcToDexBegin() const {
return PcToDexIterator(this, 0);
}
PcToDexIterator PcToDexEnd() const {
uint32_t size = PcToDexSize();
return PcToDexIterator(this, size);
}
private:
const uint8_t* const encoded_table_;
};
} // namespace art
#endif // ART_RUNTIME_MAPPING_TABLE_H_
|
