1 //===-- DWARFDebugInfoEntry.cpp -------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "DWARFDebugInfoEntry.h" 10 11 #include <cassert> 12 13 #include <algorithm> 14 #include <optional> 15 16 #include "llvm/Support/LEB128.h" 17 18 #include "lldb/Core/Module.h" 19 #include "lldb/Expression/DWARFExpression.h" 20 #include "lldb/Symbol/ObjectFile.h" 21 #include "lldb/Utility/Stream.h" 22 #include "lldb/Utility/StreamString.h" 23 24 #include "DWARFCompileUnit.h" 25 #include "DWARFDebugAbbrev.h" 26 #include "DWARFDebugAranges.h" 27 #include "DWARFDebugInfo.h" 28 #include "DWARFDebugRanges.h" 29 #include "DWARFDeclContext.h" 30 #include "DWARFFormValue.h" 31 #include "DWARFUnit.h" 32 #include "SymbolFileDWARF.h" 33 #include "SymbolFileDWARFDwo.h" 34 35 using namespace lldb_private; 36 using namespace lldb_private::dwarf; 37 extern int g_verbose; 38 39 // Extract a debug info entry for a given DWARFUnit from the data 40 // starting at the offset in offset_ptr 41 bool DWARFDebugInfoEntry::Extract(const DWARFDataExtractor &data, 42 const DWARFUnit *cu, 43 lldb::offset_t *offset_ptr) { 44 m_offset = *offset_ptr; 45 m_parent_idx = 0; 46 m_sibling_idx = 0; 47 const uint64_t abbr_idx = data.GetULEB128(offset_ptr); 48 lldbassert(abbr_idx <= UINT16_MAX); 49 m_abbr_idx = abbr_idx; 50 51 // assert (fixed_form_sizes); // For best performance this should be 52 // specified! 53 54 if (m_abbr_idx == 0) { 55 m_tag = llvm::dwarf::DW_TAG_null; 56 m_has_children = false; 57 return true; // NULL debug tag entry 58 } 59 60 lldb::offset_t offset = *offset_ptr; 61 const auto *abbrevDecl = GetAbbreviationDeclarationPtr(cu); 62 if (abbrevDecl == nullptr) { 63 cu->GetSymbolFileDWARF().GetObjectFile()->GetModule()->ReportError( 64 "[{0:x16}]: invalid abbreviation code {1}, " 65 "please file a bug and " 66 "attach the file at the start of this error message", 67 m_offset, (unsigned)abbr_idx); 68 // WE can't parse anymore if the DWARF is borked... 69 *offset_ptr = UINT32_MAX; 70 return false; 71 } 72 m_tag = abbrevDecl->Tag(); 73 m_has_children = abbrevDecl->HasChildren(); 74 // Skip all data in the .debug_info or .debug_types for the attributes 75 const uint32_t numAttributes = abbrevDecl->NumAttributes(); 76 uint32_t i; 77 dw_form_t form; 78 for (i = 0; i < numAttributes; ++i) { 79 form = abbrevDecl->GetFormByIndexUnchecked(i); 80 std::optional<uint8_t> fixed_skip_size = 81 DWARFFormValue::GetFixedSize(form, cu); 82 if (fixed_skip_size) 83 offset += *fixed_skip_size; 84 else { 85 bool form_is_indirect = false; 86 do { 87 form_is_indirect = false; 88 uint32_t form_size = 0; 89 switch (form) { 90 // Blocks if inlined data that have a length field and the data bytes 91 // inlined in the .debug_info/.debug_types 92 case DW_FORM_exprloc: 93 case DW_FORM_block: 94 form_size = data.GetULEB128(&offset); 95 break; 96 case DW_FORM_block1: 97 form_size = data.GetU8_unchecked(&offset); 98 break; 99 case DW_FORM_block2: 100 form_size = data.GetU16_unchecked(&offset); 101 break; 102 case DW_FORM_block4: 103 form_size = data.GetU32_unchecked(&offset); 104 break; 105 106 // Inlined NULL terminated C-strings 107 case DW_FORM_string: 108 data.GetCStr(&offset); 109 break; 110 111 // Compile unit address sized values 112 case DW_FORM_addr: 113 form_size = cu->GetAddressByteSize(); 114 break; 115 case DW_FORM_ref_addr: 116 if (cu->GetVersion() <= 2) 117 form_size = cu->GetAddressByteSize(); 118 else 119 form_size = 4; 120 break; 121 122 // 0 sized form 123 case DW_FORM_flag_present: 124 form_size = 0; 125 break; 126 127 // 1 byte values 128 case DW_FORM_addrx1: 129 case DW_FORM_data1: 130 case DW_FORM_flag: 131 case DW_FORM_ref1: 132 case DW_FORM_strx1: 133 form_size = 1; 134 break; 135 136 // 2 byte values 137 case DW_FORM_addrx2: 138 case DW_FORM_data2: 139 case DW_FORM_ref2: 140 case DW_FORM_strx2: 141 form_size = 2; 142 break; 143 144 // 3 byte values 145 case DW_FORM_addrx3: 146 case DW_FORM_strx3: 147 form_size = 3; 148 break; 149 150 // 4 byte values 151 case DW_FORM_addrx4: 152 case DW_FORM_data4: 153 case DW_FORM_ref4: 154 case DW_FORM_strx4: 155 form_size = 4; 156 break; 157 158 // 8 byte values 159 case DW_FORM_data8: 160 case DW_FORM_ref8: 161 case DW_FORM_ref_sig8: 162 form_size = 8; 163 break; 164 165 // signed or unsigned LEB 128 values 166 case DW_FORM_addrx: 167 case DW_FORM_loclistx: 168 case DW_FORM_rnglistx: 169 case DW_FORM_sdata: 170 case DW_FORM_udata: 171 case DW_FORM_ref_udata: 172 case DW_FORM_GNU_addr_index: 173 case DW_FORM_GNU_str_index: 174 case DW_FORM_strx: 175 data.Skip_LEB128(&offset); 176 break; 177 178 case DW_FORM_indirect: 179 form_is_indirect = true; 180 form = data.GetULEB128(&offset); 181 break; 182 183 case DW_FORM_strp: 184 case DW_FORM_line_strp: 185 case DW_FORM_sec_offset: 186 data.GetU32(&offset); 187 break; 188 189 case DW_FORM_implicit_const: 190 form_size = 0; 191 break; 192 193 default: 194 cu->GetSymbolFileDWARF().GetObjectFile()->GetModule()->ReportError( 195 "[{0:x16}]: Unsupported DW_FORM_{1:x}, please file a bug " 196 "and " 197 "attach the file at the start of this error message", 198 m_offset, (unsigned)form); 199 *offset_ptr = m_offset; 200 return false; 201 } 202 offset += form_size; 203 204 } while (form_is_indirect); 205 } 206 } 207 *offset_ptr = offset; 208 return true; 209 } 210 211 static DWARFRangeList GetRangesOrReportError(DWARFUnit &unit, 212 const DWARFDebugInfoEntry &die, 213 const DWARFFormValue &value) { 214 llvm::Expected<DWARFRangeList> expected_ranges = 215 (value.Form() == DW_FORM_rnglistx) 216 ? unit.FindRnglistFromIndex(value.Unsigned()) 217 : unit.FindRnglistFromOffset(value.Unsigned()); 218 if (expected_ranges) 219 return std::move(*expected_ranges); 220 221 unit.GetSymbolFileDWARF().GetObjectFile()->GetModule()->ReportError( 222 "[{0:x16}]: DIE has DW_AT_ranges({1} {2:x16}) attribute, but " 223 "range extraction failed ({3}), please file a bug " 224 "and attach the file at the start of this error message", 225 die.GetOffset(), 226 llvm::dwarf::FormEncodingString(value.Form()).str().c_str(), 227 value.Unsigned(), toString(expected_ranges.takeError()).c_str()); 228 return DWARFRangeList(); 229 } 230 231 // GetDIENamesAndRanges 232 // 233 // Gets the valid address ranges for a given DIE by looking for a 234 // DW_AT_low_pc/DW_AT_high_pc pair, DW_AT_entry_pc, or DW_AT_ranges attributes. 235 bool DWARFDebugInfoEntry::GetDIENamesAndRanges( 236 DWARFUnit *cu, const char *&name, const char *&mangled, 237 DWARFRangeList &ranges, int &decl_file, int &decl_line, int &decl_column, 238 int &call_file, int &call_line, int &call_column, 239 DWARFExpressionList *frame_base) const { 240 dw_addr_t lo_pc = LLDB_INVALID_ADDRESS; 241 dw_addr_t hi_pc = LLDB_INVALID_ADDRESS; 242 std::vector<DWARFDIE> dies; 243 bool set_frame_base_loclist_addr = false; 244 245 const auto *abbrevDecl = GetAbbreviationDeclarationPtr(cu); 246 247 SymbolFileDWARF &dwarf = cu->GetSymbolFileDWARF(); 248 lldb::ModuleSP module = dwarf.GetObjectFile()->GetModule(); 249 250 if (abbrevDecl) { 251 const DWARFDataExtractor &data = cu->GetData(); 252 lldb::offset_t offset = GetFirstAttributeOffset(); 253 254 if (!data.ValidOffset(offset)) 255 return false; 256 257 const uint32_t numAttributes = abbrevDecl->NumAttributes(); 258 bool do_offset = false; 259 260 for (uint32_t i = 0; i < numAttributes; ++i) { 261 DWARFFormValue form_value(cu); 262 dw_attr_t attr; 263 abbrevDecl->GetAttrAndFormValueByIndex(i, attr, form_value); 264 265 if (form_value.ExtractValue(data, &offset)) { 266 switch (attr) { 267 case DW_AT_low_pc: 268 lo_pc = form_value.Address(); 269 270 if (do_offset) 271 hi_pc += lo_pc; 272 do_offset = false; 273 break; 274 275 case DW_AT_entry_pc: 276 lo_pc = form_value.Address(); 277 break; 278 279 case DW_AT_high_pc: 280 if (form_value.Form() == DW_FORM_addr || 281 form_value.Form() == DW_FORM_addrx || 282 form_value.Form() == DW_FORM_GNU_addr_index) { 283 hi_pc = form_value.Address(); 284 } else { 285 hi_pc = form_value.Unsigned(); 286 if (lo_pc == LLDB_INVALID_ADDRESS) 287 do_offset = hi_pc != LLDB_INVALID_ADDRESS; 288 else 289 hi_pc += lo_pc; // DWARF 4 introduces <offset-from-lo-pc> to save 290 // on relocations 291 } 292 break; 293 294 case DW_AT_ranges: 295 ranges = GetRangesOrReportError(*cu, *this, form_value); 296 break; 297 298 case DW_AT_name: 299 if (name == nullptr) 300 name = form_value.AsCString(); 301 break; 302 303 case DW_AT_MIPS_linkage_name: 304 case DW_AT_linkage_name: 305 if (mangled == nullptr) 306 mangled = form_value.AsCString(); 307 break; 308 309 case DW_AT_abstract_origin: 310 dies.push_back(form_value.Reference()); 311 break; 312 313 case DW_AT_specification: 314 dies.push_back(form_value.Reference()); 315 break; 316 317 case DW_AT_decl_file: 318 if (decl_file == 0) 319 decl_file = form_value.Unsigned(); 320 break; 321 322 case DW_AT_decl_line: 323 if (decl_line == 0) 324 decl_line = form_value.Unsigned(); 325 break; 326 327 case DW_AT_decl_column: 328 if (decl_column == 0) 329 decl_column = form_value.Unsigned(); 330 break; 331 332 case DW_AT_call_file: 333 if (call_file == 0) 334 call_file = form_value.Unsigned(); 335 break; 336 337 case DW_AT_call_line: 338 if (call_line == 0) 339 call_line = form_value.Unsigned(); 340 break; 341 342 case DW_AT_call_column: 343 if (call_column == 0) 344 call_column = form_value.Unsigned(); 345 break; 346 347 case DW_AT_frame_base: 348 if (frame_base) { 349 if (form_value.BlockData()) { 350 uint32_t block_offset = 351 form_value.BlockData() - data.GetDataStart(); 352 uint32_t block_length = form_value.Unsigned(); 353 *frame_base = 354 DWARFExpressionList(module, 355 DWARFExpression(DataExtractor( 356 data, block_offset, block_length)), 357 cu); 358 } else { 359 DataExtractor data = cu->GetLocationData(); 360 const dw_offset_t offset = form_value.Unsigned(); 361 if (data.ValidOffset(offset)) { 362 data = DataExtractor(data, offset, data.GetByteSize() - offset); 363 if (lo_pc != LLDB_INVALID_ADDRESS) { 364 assert(lo_pc >= cu->GetBaseAddress()); 365 DWARFExpression::ParseDWARFLocationList(cu, data, frame_base); 366 frame_base->SetFuncFileAddress(lo_pc); 367 } else 368 set_frame_base_loclist_addr = true; 369 } 370 } 371 } 372 break; 373 374 default: 375 break; 376 } 377 } 378 } 379 } 380 381 if (ranges.IsEmpty()) { 382 if (lo_pc != LLDB_INVALID_ADDRESS) { 383 if (hi_pc != LLDB_INVALID_ADDRESS && hi_pc > lo_pc) 384 ranges.Append(DWARFRangeList::Entry(lo_pc, hi_pc - lo_pc)); 385 else 386 ranges.Append(DWARFRangeList::Entry(lo_pc, 0)); 387 } 388 } 389 390 if (set_frame_base_loclist_addr) { 391 dw_addr_t lowest_range_pc = ranges.GetMinRangeBase(0); 392 assert(lowest_range_pc >= cu->GetBaseAddress()); 393 frame_base->SetFuncFileAddress(lowest_range_pc); 394 } 395 396 if (ranges.IsEmpty() || name == nullptr || mangled == nullptr) { 397 for (const DWARFDIE &die : dies) { 398 if (die) { 399 die.GetDIE()->GetDIENamesAndRanges(die.GetCU(), name, mangled, ranges, 400 decl_file, decl_line, decl_column, 401 call_file, call_line, call_column); 402 } 403 } 404 } 405 return !ranges.IsEmpty(); 406 } 407 408 // Get all attribute values for a given DIE, including following any 409 // specification or abstract origin attributes and including those in the 410 // results. Any duplicate attributes will have the first instance take 411 // precedence (this can happen for declaration attributes). 412 size_t DWARFDebugInfoEntry::GetAttributes(DWARFUnit *cu, 413 DWARFAttributes &attributes, 414 Recurse recurse, 415 uint32_t curr_depth) const { 416 const auto *abbrevDecl = GetAbbreviationDeclarationPtr(cu); 417 if (abbrevDecl) { 418 const DWARFDataExtractor &data = cu->GetData(); 419 lldb::offset_t offset = GetFirstAttributeOffset(); 420 421 const uint32_t num_attributes = abbrevDecl->NumAttributes(); 422 for (uint32_t i = 0; i < num_attributes; ++i) { 423 DWARFFormValue form_value(cu); 424 dw_attr_t attr; 425 abbrevDecl->GetAttrAndFormValueByIndex(i, attr, form_value); 426 const dw_form_t form = form_value.Form(); 427 428 // If we are tracking down DW_AT_specification or DW_AT_abstract_origin 429 // attributes, the depth will be non-zero. We need to omit certain 430 // attributes that don't make sense. 431 switch (attr) { 432 case DW_AT_sibling: 433 case DW_AT_declaration: 434 if (curr_depth > 0) { 435 // This attribute doesn't make sense when combined with the DIE that 436 // references this DIE. We know a DIE is referencing this DIE because 437 // curr_depth is not zero 438 break; 439 } 440 [[fallthrough]]; 441 default: 442 attributes.Append(form_value, offset, attr); 443 break; 444 } 445 446 if (recurse == Recurse::yes && 447 ((attr == DW_AT_specification) || (attr == DW_AT_abstract_origin))) { 448 if (form_value.ExtractValue(data, &offset)) { 449 DWARFDIE spec_die = form_value.Reference(); 450 if (spec_die) 451 spec_die.GetDIE()->GetAttributes(spec_die.GetCU(), attributes, 452 recurse, curr_depth + 1); 453 } 454 } else { 455 std::optional<uint8_t> fixed_skip_size = 456 DWARFFormValue::GetFixedSize(form, cu); 457 if (fixed_skip_size) 458 offset += *fixed_skip_size; 459 else 460 DWARFFormValue::SkipValue(form, data, &offset, cu); 461 } 462 } 463 } else { 464 attributes.Clear(); 465 } 466 return attributes.Size(); 467 } 468 469 // GetAttributeValue 470 // 471 // Get the value of an attribute and return the .debug_info or .debug_types 472 // offset of the attribute if it was properly extracted into form_value, 473 // or zero if we fail since an offset of zero is invalid for an attribute (it 474 // would be a compile unit header). 475 dw_offset_t DWARFDebugInfoEntry::GetAttributeValue( 476 const DWARFUnit *cu, const dw_attr_t attr, DWARFFormValue &form_value, 477 dw_offset_t *end_attr_offset_ptr, 478 bool check_specification_or_abstract_origin) const { 479 if (const auto *abbrevDecl = GetAbbreviationDeclarationPtr(cu)) { 480 uint32_t attr_idx = abbrevDecl->FindAttributeIndex(attr); 481 482 if (attr_idx != DW_INVALID_INDEX) { 483 const DWARFDataExtractor &data = cu->GetData(); 484 lldb::offset_t offset = GetFirstAttributeOffset(); 485 486 uint32_t idx = 0; 487 while (idx < attr_idx) 488 DWARFFormValue::SkipValue(abbrevDecl->GetFormByIndex(idx++), 489 data, &offset, cu); 490 491 const dw_offset_t attr_offset = offset; 492 form_value.SetUnit(cu); 493 form_value.SetForm(abbrevDecl->GetFormByIndex(idx)); 494 if (form_value.ExtractValue(data, &offset)) { 495 if (end_attr_offset_ptr) 496 *end_attr_offset_ptr = offset; 497 return attr_offset; 498 } 499 } 500 } 501 502 if (check_specification_or_abstract_origin) { 503 if (GetAttributeValue(cu, DW_AT_specification, form_value)) { 504 DWARFDIE die = form_value.Reference(); 505 if (die) { 506 dw_offset_t die_offset = die.GetDIE()->GetAttributeValue( 507 die.GetCU(), attr, form_value, end_attr_offset_ptr, false); 508 if (die_offset) 509 return die_offset; 510 } 511 } 512 513 if (GetAttributeValue(cu, DW_AT_abstract_origin, form_value)) { 514 DWARFDIE die = form_value.Reference(); 515 if (die) { 516 dw_offset_t die_offset = die.GetDIE()->GetAttributeValue( 517 die.GetCU(), attr, form_value, end_attr_offset_ptr, false); 518 if (die_offset) 519 return die_offset; 520 } 521 } 522 } 523 return 0; 524 } 525 526 // GetAttributeValueAsString 527 // 528 // Get the value of an attribute as a string return it. The resulting pointer 529 // to the string data exists within the supplied SymbolFileDWARF and will only 530 // be available as long as the SymbolFileDWARF is still around and it's content 531 // doesn't change. 532 const char *DWARFDebugInfoEntry::GetAttributeValueAsString( 533 const DWARFUnit *cu, const dw_attr_t attr, const char *fail_value, 534 bool check_specification_or_abstract_origin) const { 535 DWARFFormValue form_value; 536 if (GetAttributeValue(cu, attr, form_value, nullptr, 537 check_specification_or_abstract_origin)) 538 return form_value.AsCString(); 539 return fail_value; 540 } 541 542 // GetAttributeValueAsUnsigned 543 // 544 // Get the value of an attribute as unsigned and return it. 545 uint64_t DWARFDebugInfoEntry::GetAttributeValueAsUnsigned( 546 const DWARFUnit *cu, const dw_attr_t attr, uint64_t fail_value, 547 bool check_specification_or_abstract_origin) const { 548 DWARFFormValue form_value; 549 if (GetAttributeValue(cu, attr, form_value, nullptr, 550 check_specification_or_abstract_origin)) 551 return form_value.Unsigned(); 552 return fail_value; 553 } 554 555 std::optional<uint64_t> 556 DWARFDebugInfoEntry::GetAttributeValueAsOptionalUnsigned( 557 const DWARFUnit *cu, const dw_attr_t attr, 558 bool check_specification_or_abstract_origin) const { 559 DWARFFormValue form_value; 560 if (GetAttributeValue(cu, attr, form_value, nullptr, 561 check_specification_or_abstract_origin)) 562 return form_value.Unsigned(); 563 return std::nullopt; 564 } 565 566 // GetAttributeValueAsReference 567 // 568 // Get the value of an attribute as reference and fix up and compile unit 569 // relative offsets as needed. 570 DWARFDIE DWARFDebugInfoEntry::GetAttributeValueAsReference( 571 const DWARFUnit *cu, const dw_attr_t attr, 572 bool check_specification_or_abstract_origin) const { 573 DWARFFormValue form_value; 574 if (GetAttributeValue(cu, attr, form_value, nullptr, 575 check_specification_or_abstract_origin)) 576 return form_value.Reference(); 577 return {}; 578 } 579 580 uint64_t DWARFDebugInfoEntry::GetAttributeValueAsAddress( 581 const DWARFUnit *cu, const dw_attr_t attr, uint64_t fail_value, 582 bool check_specification_or_abstract_origin) const { 583 DWARFFormValue form_value; 584 if (GetAttributeValue(cu, attr, form_value, nullptr, 585 check_specification_or_abstract_origin)) 586 return form_value.Address(); 587 return fail_value; 588 } 589 590 // GetAttributeHighPC 591 // 592 // Get the hi_pc, adding hi_pc to lo_pc when specified as an <offset-from-low- 593 // pc>. 594 // 595 // Returns the hi_pc or fail_value. 596 dw_addr_t DWARFDebugInfoEntry::GetAttributeHighPC( 597 const DWARFUnit *cu, dw_addr_t lo_pc, uint64_t fail_value, 598 bool check_specification_or_abstract_origin) const { 599 DWARFFormValue form_value; 600 if (GetAttributeValue(cu, DW_AT_high_pc, form_value, nullptr, 601 check_specification_or_abstract_origin)) { 602 dw_form_t form = form_value.Form(); 603 if (form == DW_FORM_addr || form == DW_FORM_addrx || 604 form == DW_FORM_GNU_addr_index) 605 return form_value.Address(); 606 607 // DWARF4 can specify the hi_pc as an <offset-from-lowpc> 608 return lo_pc + form_value.Unsigned(); 609 } 610 return fail_value; 611 } 612 613 // GetAttributeAddressRange 614 // 615 // Get the lo_pc and hi_pc, adding hi_pc to lo_pc when specified as an <offset- 616 // from-low-pc>. 617 // 618 // Returns true or sets lo_pc and hi_pc to fail_value. 619 bool DWARFDebugInfoEntry::GetAttributeAddressRange( 620 const DWARFUnit *cu, dw_addr_t &lo_pc, dw_addr_t &hi_pc, 621 uint64_t fail_value, bool check_specification_or_abstract_origin) const { 622 lo_pc = GetAttributeValueAsAddress(cu, DW_AT_low_pc, fail_value, 623 check_specification_or_abstract_origin); 624 if (lo_pc != fail_value) { 625 hi_pc = GetAttributeHighPC(cu, lo_pc, fail_value, 626 check_specification_or_abstract_origin); 627 if (hi_pc != fail_value) 628 return true; 629 } 630 lo_pc = fail_value; 631 hi_pc = fail_value; 632 return false; 633 } 634 635 size_t DWARFDebugInfoEntry::GetAttributeAddressRanges( 636 DWARFUnit *cu, DWARFRangeList &ranges, bool check_hi_lo_pc, 637 bool check_specification_or_abstract_origin) const { 638 ranges.Clear(); 639 640 DWARFFormValue form_value; 641 if (GetAttributeValue(cu, DW_AT_ranges, form_value)) { 642 ranges = GetRangesOrReportError(*cu, *this, form_value); 643 } else if (check_hi_lo_pc) { 644 dw_addr_t lo_pc = LLDB_INVALID_ADDRESS; 645 dw_addr_t hi_pc = LLDB_INVALID_ADDRESS; 646 if (GetAttributeAddressRange(cu, lo_pc, hi_pc, LLDB_INVALID_ADDRESS, 647 check_specification_or_abstract_origin)) { 648 if (lo_pc < hi_pc) 649 ranges.Append(DWARFRangeList::Entry(lo_pc, hi_pc - lo_pc)); 650 } 651 } 652 return ranges.GetSize(); 653 } 654 655 // GetName 656 // 657 // Get value of the DW_AT_name attribute and return it if one exists, else 658 // return NULL. 659 const char *DWARFDebugInfoEntry::GetName(const DWARFUnit *cu) const { 660 return GetAttributeValueAsString(cu, DW_AT_name, nullptr, true); 661 } 662 663 // GetMangledName 664 // 665 // Get value of the DW_AT_MIPS_linkage_name attribute and return it if one 666 // exists, else return the value of the DW_AT_name attribute 667 const char * 668 DWARFDebugInfoEntry::GetMangledName(const DWARFUnit *cu, 669 bool substitute_name_allowed) const { 670 const char *name = nullptr; 671 672 name = GetAttributeValueAsString(cu, DW_AT_MIPS_linkage_name, nullptr, true); 673 if (name) 674 return name; 675 676 name = GetAttributeValueAsString(cu, DW_AT_linkage_name, nullptr, true); 677 if (name) 678 return name; 679 680 if (!substitute_name_allowed) 681 return nullptr; 682 683 name = GetAttributeValueAsString(cu, DW_AT_name, nullptr, true); 684 return name; 685 } 686 687 // GetPubname 688 // 689 // Get value the name for a DIE as it should appear for a .debug_pubnames or 690 // .debug_pubtypes section. 691 const char *DWARFDebugInfoEntry::GetPubname(const DWARFUnit *cu) const { 692 const char *name = nullptr; 693 if (!cu) 694 return name; 695 696 name = GetAttributeValueAsString(cu, DW_AT_MIPS_linkage_name, nullptr, true); 697 if (name) 698 return name; 699 700 name = GetAttributeValueAsString(cu, DW_AT_linkage_name, nullptr, true); 701 if (name) 702 return name; 703 704 name = GetAttributeValueAsString(cu, DW_AT_name, nullptr, true); 705 return name; 706 } 707 708 /// This function is builds a table very similar to the standard .debug_aranges 709 /// table, except that the actual DIE offset for the function is placed in the 710 /// table instead of the compile unit offset. 711 void DWARFDebugInfoEntry::BuildFunctionAddressRangeTable( 712 DWARFUnit *cu, DWARFDebugAranges *debug_aranges) const { 713 if (m_tag) { 714 if (m_tag == DW_TAG_subprogram) { 715 DWARFRangeList ranges; 716 GetAttributeAddressRanges(cu, ranges, 717 /*check_hi_lo_pc=*/true); 718 for (const auto &r : ranges) { 719 debug_aranges->AppendRange(GetOffset(), r.GetRangeBase(), 720 r.GetRangeEnd()); 721 } 722 } 723 724 const DWARFDebugInfoEntry *child = GetFirstChild(); 725 while (child) { 726 child->BuildFunctionAddressRangeTable(cu, debug_aranges); 727 child = child->GetSibling(); 728 } 729 } 730 } 731 732 DWARFDeclContext 733 DWARFDebugInfoEntry::GetDWARFDeclContextStatic(const DWARFDebugInfoEntry *die, 734 DWARFUnit *cu) { 735 DWARFDeclContext dwarf_decl_ctx; 736 for (;;) { 737 const dw_tag_t tag = die->Tag(); 738 if (tag == DW_TAG_compile_unit || tag == DW_TAG_partial_unit) 739 return dwarf_decl_ctx; 740 dwarf_decl_ctx.AppendDeclContext(tag, die->GetName(cu)); 741 DWARFDIE parent_decl_ctx_die = die->GetParentDeclContextDIE(cu); 742 if (!parent_decl_ctx_die || parent_decl_ctx_die.GetDIE() == die) 743 return dwarf_decl_ctx; 744 if (parent_decl_ctx_die.Tag() == DW_TAG_compile_unit || 745 parent_decl_ctx_die.Tag() == DW_TAG_partial_unit) 746 return dwarf_decl_ctx; 747 die = parent_decl_ctx_die.GetDIE(); 748 cu = parent_decl_ctx_die.GetCU(); 749 } 750 } 751 752 DWARFDeclContext DWARFDebugInfoEntry::GetDWARFDeclContext(DWARFUnit *cu) const { 753 return GetDWARFDeclContextStatic(this, cu); 754 } 755 756 DWARFDIE 757 DWARFDebugInfoEntry::GetParentDeclContextDIE(DWARFUnit *cu) const { 758 DWARFAttributes attributes; 759 GetAttributes(cu, attributes, Recurse::yes); 760 return GetParentDeclContextDIE(cu, attributes); 761 } 762 763 DWARFDIE 764 DWARFDebugInfoEntry::GetParentDeclContextDIE( 765 DWARFUnit *cu, const DWARFAttributes &attributes) const { 766 DWARFDIE die(cu, const_cast<DWARFDebugInfoEntry *>(this)); 767 768 while (die) { 769 // If this is the original DIE that we are searching for a declaration for, 770 // then don't look in the cache as we don't want our own decl context to be 771 // our decl context... 772 if (die.GetDIE() != this) { 773 switch (die.Tag()) { 774 case DW_TAG_compile_unit: 775 case DW_TAG_partial_unit: 776 case DW_TAG_namespace: 777 case DW_TAG_structure_type: 778 case DW_TAG_union_type: 779 case DW_TAG_class_type: 780 return die; 781 782 default: 783 break; 784 } 785 } 786 787 DWARFDIE spec_die = attributes.FormValueAsReference(DW_AT_specification); 788 if (spec_die) { 789 DWARFDIE decl_ctx_die = spec_die.GetParentDeclContextDIE(); 790 if (decl_ctx_die) 791 return decl_ctx_die; 792 } 793 794 DWARFDIE abs_die = attributes.FormValueAsReference(DW_AT_abstract_origin); 795 if (abs_die) { 796 DWARFDIE decl_ctx_die = abs_die.GetParentDeclContextDIE(); 797 if (decl_ctx_die) 798 return decl_ctx_die; 799 } 800 801 die = die.GetParent(); 802 } 803 return DWARFDIE(); 804 } 805 806 lldb::offset_t DWARFDebugInfoEntry::GetFirstAttributeOffset() const { 807 return GetOffset() + llvm::getULEB128Size(m_abbr_idx); 808 } 809 810 const DWARFAbbreviationDeclaration * 811 DWARFDebugInfoEntry::GetAbbreviationDeclarationPtr(const DWARFUnit *cu) const { 812 if (cu) { 813 const DWARFAbbreviationDeclarationSet *abbrev_set = cu->GetAbbreviations(); 814 if (abbrev_set) 815 return abbrev_set->GetAbbreviationDeclaration(m_abbr_idx); 816 } 817 return nullptr; 818 } 819 820 bool DWARFDebugInfoEntry::IsGlobalOrStaticScopeVariable() const { 821 if (Tag() != DW_TAG_variable) 822 return false; 823 const DWARFDebugInfoEntry *parent_die = GetParent(); 824 while (parent_die != nullptr) { 825 switch (parent_die->Tag()) { 826 case DW_TAG_subprogram: 827 case DW_TAG_lexical_block: 828 case DW_TAG_inlined_subroutine: 829 return false; 830 831 case DW_TAG_compile_unit: 832 case DW_TAG_partial_unit: 833 return true; 834 835 default: 836 break; 837 } 838 parent_die = parent_die->GetParent(); 839 } 840 return false; 841 } 842 843 bool DWARFDebugInfoEntry::operator==(const DWARFDebugInfoEntry &rhs) const { 844 return m_offset == rhs.m_offset && m_parent_idx == rhs.m_parent_idx && 845 m_sibling_idx == rhs.m_sibling_idx && 846 m_abbr_idx == rhs.m_abbr_idx && m_has_children == rhs.m_has_children && 847 m_tag == rhs.m_tag; 848 } 849 850 bool DWARFDebugInfoEntry::operator!=(const DWARFDebugInfoEntry &rhs) const { 851 return !(*this == rhs); 852 } 853