David Srbecky | b536247 | 2015-04-08 19:37:39 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2014 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #ifndef ART_COMPILER_DWARF_DEBUG_INFO_ENTRY_WRITER_H_ |
| 18 | #define ART_COMPILER_DWARF_DEBUG_INFO_ENTRY_WRITER_H_ |
| 19 | |
David Srbecky | 2f6cdb0 | 2015-04-11 00:17:53 +0100 | [diff] [blame] | 20 | #include <cstdint> |
David Srbecky | b536247 | 2015-04-08 19:37:39 +0100 | [diff] [blame] | 21 | #include <unordered_map> |
| 22 | |
David Srbecky | 7c869b3 | 2015-04-12 08:47:47 +0100 | [diff] [blame] | 23 | #include "dwarf/dwarf_constants.h" |
| 24 | #include "dwarf/writer.h" |
David Srbecky | b536247 | 2015-04-08 19:37:39 +0100 | [diff] [blame] | 25 | #include "leb128.h" |
David Srbecky | b536247 | 2015-04-08 19:37:39 +0100 | [diff] [blame] | 26 | |
| 27 | namespace art { |
| 28 | namespace dwarf { |
| 29 | |
| 30 | // 32-bit FNV-1a hash function which we use to find duplicate abbreviations. |
| 31 | // See http://en.wikipedia.org/wiki/Fowler%E2%80%93Noll%E2%80%93Vo_hash_function |
| 32 | template< typename Allocator > |
| 33 | struct FNVHash { |
| 34 | size_t operator()(const std::vector<uint8_t, Allocator>& v) const { |
| 35 | uint32_t hash = 2166136261u; |
| 36 | for (size_t i = 0; i < v.size(); i++) { |
| 37 | hash = (hash ^ v[i]) * 16777619u; |
| 38 | } |
| 39 | return hash; |
| 40 | } |
| 41 | }; |
| 42 | |
| 43 | /* |
| 44 | * Writer for debug information entries (DIE). |
| 45 | * It also handles generation of abbreviations. |
| 46 | * |
| 47 | * Usage: |
| 48 | * StartTag(DW_TAG_compile_unit, DW_CHILDREN_yes); |
| 49 | * WriteStrp(DW_AT_producer, "Compiler name", debug_str); |
| 50 | * StartTag(DW_TAG_subprogram, DW_CHILDREN_no); |
| 51 | * WriteStrp(DW_AT_name, "Foo", debug_str); |
| 52 | * EndTag(); |
| 53 | * EndTag(); |
| 54 | */ |
| 55 | template< typename Allocator = std::allocator<uint8_t> > |
| 56 | class DebugInfoEntryWriter FINAL : private Writer<Allocator> { |
| 57 | public: |
| 58 | // Start debugging information entry. |
| 59 | void StartTag(Tag tag, Children children) { |
| 60 | DCHECK(has_children) << "This tag can not have nested tags"; |
| 61 | if (inside_entry_) { |
| 62 | // Write abbrev code for the previous entry. |
| 63 | this->UpdateUleb128(abbrev_code_offset_, EndAbbrev()); |
| 64 | inside_entry_ = false; |
| 65 | } |
| 66 | StartAbbrev(tag, children); |
| 67 | // Abbrev code placeholder of sufficient size. |
| 68 | abbrev_code_offset_ = this->data()->size(); |
| 69 | this->PushUleb128(NextAbbrevCode()); |
| 70 | depth_++; |
| 71 | inside_entry_ = true; |
| 72 | has_children = (children == DW_CHILDREN_yes); |
| 73 | } |
| 74 | |
| 75 | // End debugging information entry. |
| 76 | void EndTag() { |
| 77 | DCHECK_GT(depth_, 0); |
| 78 | if (inside_entry_) { |
| 79 | // Write abbrev code for this tag. |
| 80 | this->UpdateUleb128(abbrev_code_offset_, EndAbbrev()); |
| 81 | inside_entry_ = false; |
| 82 | } |
| 83 | if (has_children) { |
| 84 | this->PushUint8(0); // End of children. |
| 85 | } |
| 86 | depth_--; |
| 87 | has_children = true; // Parent tag obviously has children. |
| 88 | } |
| 89 | |
| 90 | void WriteAddr(Attribute attrib, uint64_t value) { |
| 91 | AddAbbrevAttribute(attrib, DW_FORM_addr); |
David Srbecky | 2f6cdb0 | 2015-04-11 00:17:53 +0100 | [diff] [blame] | 92 | patch_locations_.push_back(this->data()->size()); |
David Srbecky | b536247 | 2015-04-08 19:37:39 +0100 | [diff] [blame] | 93 | if (is64bit_) { |
| 94 | this->PushUint64(value); |
| 95 | } else { |
| 96 | this->PushUint32(value); |
| 97 | } |
| 98 | } |
| 99 | |
| 100 | void WriteBlock(Attribute attrib, const void* ptr, int size) { |
| 101 | AddAbbrevAttribute(attrib, DW_FORM_block); |
| 102 | this->PushUleb128(size); |
| 103 | this->PushData(ptr, size); |
| 104 | } |
| 105 | |
| 106 | void WriteData1(Attribute attrib, uint8_t value) { |
| 107 | AddAbbrevAttribute(attrib, DW_FORM_data1); |
| 108 | this->PushUint8(value); |
| 109 | } |
| 110 | |
| 111 | void WriteData2(Attribute attrib, uint16_t value) { |
| 112 | AddAbbrevAttribute(attrib, DW_FORM_data2); |
| 113 | this->PushUint16(value); |
| 114 | } |
| 115 | |
| 116 | void WriteData4(Attribute attrib, uint32_t value) { |
| 117 | AddAbbrevAttribute(attrib, DW_FORM_data4); |
| 118 | this->PushUint32(value); |
| 119 | } |
| 120 | |
| 121 | void WriteData8(Attribute attrib, uint64_t value) { |
| 122 | AddAbbrevAttribute(attrib, DW_FORM_data8); |
| 123 | this->PushUint64(value); |
| 124 | } |
| 125 | |
| 126 | void WriteSdata(Attribute attrib, int value) { |
| 127 | AddAbbrevAttribute(attrib, DW_FORM_sdata); |
| 128 | this->PushSleb128(value); |
| 129 | } |
| 130 | |
| 131 | void WriteUdata(Attribute attrib, int value) { |
| 132 | AddAbbrevAttribute(attrib, DW_FORM_udata); |
| 133 | this->PushUleb128(value); |
| 134 | } |
| 135 | |
| 136 | void WriteUdata(Attribute attrib, uint32_t value) { |
| 137 | AddAbbrevAttribute(attrib, DW_FORM_udata); |
| 138 | this->PushUleb128(value); |
| 139 | } |
| 140 | |
| 141 | void WriteFlag(Attribute attrib, bool value) { |
| 142 | AddAbbrevAttribute(attrib, DW_FORM_flag); |
| 143 | this->PushUint8(value ? 1 : 0); |
| 144 | } |
| 145 | |
| 146 | void WriteRef4(Attribute attrib, int cu_offset) { |
| 147 | AddAbbrevAttribute(attrib, DW_FORM_ref4); |
| 148 | this->PushUint32(cu_offset); |
| 149 | } |
| 150 | |
| 151 | void WriteRef(Attribute attrib, int cu_offset) { |
| 152 | AddAbbrevAttribute(attrib, DW_FORM_ref_udata); |
| 153 | this->PushUleb128(cu_offset); |
| 154 | } |
| 155 | |
| 156 | void WriteString(Attribute attrib, const char* value) { |
| 157 | AddAbbrevAttribute(attrib, DW_FORM_string); |
| 158 | this->PushString(value); |
| 159 | } |
| 160 | |
| 161 | void WriteStrp(Attribute attrib, int address) { |
| 162 | AddAbbrevAttribute(attrib, DW_FORM_strp); |
| 163 | this->PushUint32(address); |
| 164 | } |
| 165 | |
| 166 | void WriteStrp(Attribute attrib, const char* value, std::vector<uint8_t>* debug_str) { |
| 167 | AddAbbrevAttribute(attrib, DW_FORM_strp); |
| 168 | int address = debug_str->size(); |
| 169 | debug_str->insert(debug_str->end(), value, value + strlen(value) + 1); |
| 170 | this->PushUint32(address); |
| 171 | } |
| 172 | |
David Srbecky | 2f6cdb0 | 2015-04-11 00:17:53 +0100 | [diff] [blame] | 173 | bool Is64bit() const { return is64bit_; } |
| 174 | |
| 175 | const std::vector<uintptr_t>& GetPatchLocations() const { |
| 176 | return patch_locations_; |
| 177 | } |
David Srbecky | b536247 | 2015-04-08 19:37:39 +0100 | [diff] [blame] | 178 | |
| 179 | using Writer<Allocator>::data; |
| 180 | |
| 181 | DebugInfoEntryWriter(bool is64bitArch, |
| 182 | std::vector<uint8_t, Allocator>* debug_abbrev, |
| 183 | const Allocator& alloc = Allocator()) |
| 184 | : Writer<Allocator>(&entries_), |
| 185 | debug_abbrev_(debug_abbrev), |
| 186 | current_abbrev_(alloc), |
| 187 | abbrev_codes_(alloc), |
| 188 | entries_(alloc), |
| 189 | is64bit_(is64bitArch) { |
| 190 | debug_abbrev_.PushUint8(0); // Add abbrev table terminator. |
| 191 | } |
| 192 | |
| 193 | ~DebugInfoEntryWriter() { |
| 194 | DCHECK_EQ(depth_, 0); |
| 195 | } |
| 196 | |
| 197 | private: |
| 198 | // Start abbreviation declaration. |
| 199 | void StartAbbrev(Tag tag, Children children) { |
| 200 | DCHECK(!inside_entry_); |
| 201 | current_abbrev_.clear(); |
| 202 | EncodeUnsignedLeb128(¤t_abbrev_, tag); |
| 203 | current_abbrev_.push_back(children); |
| 204 | } |
| 205 | |
| 206 | // Add attribute specification. |
| 207 | void AddAbbrevAttribute(Attribute name, Form type) { |
| 208 | DCHECK(inside_entry_) << "Call StartTag before adding attributes."; |
| 209 | EncodeUnsignedLeb128(¤t_abbrev_, name); |
| 210 | EncodeUnsignedLeb128(¤t_abbrev_, type); |
| 211 | } |
| 212 | |
| 213 | int NextAbbrevCode() { |
| 214 | return 1 + abbrev_codes_.size(); |
| 215 | } |
| 216 | |
| 217 | // End abbreviation declaration and return its code. |
| 218 | int EndAbbrev() { |
| 219 | DCHECK(inside_entry_); |
| 220 | auto it = abbrev_codes_.insert(std::make_pair(std::move(current_abbrev_), |
| 221 | NextAbbrevCode())); |
| 222 | int abbrev_code = it.first->second; |
| 223 | if (UNLIKELY(it.second)) { // Inserted new entry. |
| 224 | const std::vector<uint8_t, Allocator>& abbrev = it.first->first; |
| 225 | debug_abbrev_.Pop(); // Remove abbrev table terminator. |
| 226 | debug_abbrev_.PushUleb128(abbrev_code); |
| 227 | debug_abbrev_.PushData(abbrev.data(), abbrev.size()); |
| 228 | debug_abbrev_.PushUint8(0); // Attribute list end. |
| 229 | debug_abbrev_.PushUint8(0); // Attribute list end. |
| 230 | debug_abbrev_.PushUint8(0); // Add abbrev table terminator. |
| 231 | } |
| 232 | return abbrev_code; |
| 233 | } |
| 234 | |
| 235 | private: |
| 236 | // Fields for writing and deduplication of abbrevs. |
| 237 | Writer<Allocator> debug_abbrev_; |
| 238 | std::vector<uint8_t, Allocator> current_abbrev_; |
| 239 | std::unordered_map<std::vector<uint8_t, Allocator>, int, |
| 240 | FNVHash<Allocator> > abbrev_codes_; |
| 241 | |
| 242 | // Fields for writing of debugging information entries. |
| 243 | std::vector<uint8_t, Allocator> entries_; |
| 244 | bool is64bit_; |
| 245 | int depth_ = 0; |
| 246 | size_t abbrev_code_offset_ = 0; // Location to patch once we know the code. |
| 247 | bool inside_entry_ = false; // Entry ends at first child (if any). |
| 248 | bool has_children = true; |
David Srbecky | 2f6cdb0 | 2015-04-11 00:17:53 +0100 | [diff] [blame] | 249 | std::vector<uintptr_t> patch_locations_; |
David Srbecky | b536247 | 2015-04-08 19:37:39 +0100 | [diff] [blame] | 250 | }; |
| 251 | |
| 252 | } // namespace dwarf |
| 253 | } // namespace art |
| 254 | |
| 255 | #endif // ART_COMPILER_DWARF_DEBUG_INFO_ENTRY_WRITER_H_ |