DWARFDebugInfoEntry.cpp revision 360784 
1//===-- DWARFDebugInfoEntry.cpp ---------------------------------*- C++ -*-===//
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 <assert.h>
12
13#include <algorithm>
14
15#include "llvm/Support/LEB128.h"
16
17#include "lldb/Core/Module.h"
18#include "lldb/Expression/DWARFExpression.h"
19#include "lldb/Symbol/ObjectFile.h"
20#include "lldb/Utility/Stream.h"
21
22#include "DWARFCompileUnit.h"
23#include "DWARFDebugAbbrev.h"
24#include "DWARFDebugAranges.h"
25#include "DWARFDebugInfo.h"
26#include "DWARFDebugRanges.h"
27#include "DWARFDeclContext.h"
28#include "DWARFFormValue.h"
29#include "DWARFUnit.h"
30#include "SymbolFileDWARF.h"
31#include "SymbolFileDWARFDwo.h"
32
33using namespace lldb_private;
34using namespace std;
35extern int g_verbose;
36
37// Extract a debug info entry for a given DWARFUnit from the data
38// starting at the offset in offset_ptr
39bool DWARFDebugInfoEntry::Extract(const DWARFDataExtractor &data,
40                                  const DWARFUnit *cu,
41                                  lldb::offset_t *offset_ptr) {
42  m_offset = *offset_ptr;
43  m_parent_idx = 0;
44  m_sibling_idx = 0;
45  const uint64_t abbr_idx = data.GetULEB128(offset_ptr);
46  lldbassert(abbr_idx <= UINT16_MAX);
47  m_abbr_idx = abbr_idx;
48
49  // assert (fixed_form_sizes);  // For best performance this should be
50  // specified!
51
52  if (m_abbr_idx) {
53    lldb::offset_t offset = *offset_ptr;
54    const auto *abbrevDecl = GetAbbreviationDeclarationPtr(cu);
55    if (abbrevDecl == nullptr) {
56      cu->GetSymbolFileDWARF().GetObjectFile()->GetModule()->ReportError(
57          "{0x%8.8x}: invalid abbreviation code %u, please file a bug and "
58          "attach the file at the start of this error message",
59          m_offset, (unsigned)abbr_idx);
60      // WE can't parse anymore if the DWARF is borked...
61      *offset_ptr = UINT32_MAX;
62      return false;
63    }
64    m_tag = abbrevDecl->Tag();
65    m_has_children = abbrevDecl->HasChildren();
66    // Skip all data in the .debug_info or .debug_types for the attributes
67    const uint32_t numAttributes = abbrevDecl->NumAttributes();
68    uint32_t i;
69    dw_form_t form;
70    for (i = 0; i < numAttributes; ++i) {
71      form = abbrevDecl->GetFormByIndexUnchecked(i);
72      llvm::Optional<uint8_t> fixed_skip_size =
73          DWARFFormValue::GetFixedSize(form, cu);
74      if (fixed_skip_size)
75        offset += *fixed_skip_size;
76      else {
77        bool form_is_indirect = false;
78        do {
79          form_is_indirect = false;
80          uint32_t form_size = 0;
81          switch (form) {
82          // Blocks if inlined data that have a length field and the data bytes
83          // inlined in the .debug_info/.debug_types
84          case DW_FORM_exprloc:
85          case DW_FORM_block:
86            form_size = data.GetULEB128(&offset);
87            break;
88          case DW_FORM_block1:
89            form_size = data.GetU8_unchecked(&offset);
90            break;
91          case DW_FORM_block2:
92            form_size = data.GetU16_unchecked(&offset);
93            break;
94          case DW_FORM_block4:
95            form_size = data.GetU32_unchecked(&offset);
96            break;
97
98          // Inlined NULL terminated C-strings
99          case DW_FORM_string:
100            data.GetCStr(&offset);
101            break;
102
103          // Compile unit address sized values
104          case DW_FORM_addr:
105            form_size = cu->GetAddressByteSize();
106            break;
107          case DW_FORM_ref_addr:
108            if (cu->GetVersion() <= 2)
109              form_size = cu->GetAddressByteSize();
110            else
111              form_size = 4;
112            break;
113
114          // 0 sized form
115          case DW_FORM_flag_present:
116            form_size = 0;
117            break;
118
119          // 1 byte values
120          case DW_FORM_addrx1:
121          case DW_FORM_data1:
122          case DW_FORM_flag:
123          case DW_FORM_ref1:
124          case DW_FORM_strx1:
125            form_size = 1;
126            break;
127
128          // 2 byte values
129          case DW_FORM_addrx2:
130          case DW_FORM_data2:
131          case DW_FORM_ref2:
132          case DW_FORM_strx2:
133            form_size = 2;
134            break;
135
136          // 3 byte values
137          case DW_FORM_addrx3:
138          case DW_FORM_strx3:
139            form_size = 3;
140            break;
141
142          // 4 byte values
143          case DW_FORM_addrx4:
144          case DW_FORM_data4:
145          case DW_FORM_ref4:
146          case DW_FORM_strx4:
147            form_size = 4;
148            break;
149
150          // 8 byte values
151          case DW_FORM_data8:
152          case DW_FORM_ref8:
153          case DW_FORM_ref_sig8:
154            form_size = 8;
155            break;
156
157          // signed or unsigned LEB 128 values
158          case DW_FORM_addrx:
159          case DW_FORM_loclistx:
160          case DW_FORM_rnglistx:
161          case DW_FORM_sdata:
162          case DW_FORM_udata:
163          case DW_FORM_ref_udata:
164          case DW_FORM_GNU_addr_index:
165          case DW_FORM_GNU_str_index:
166          case DW_FORM_strx:
167            data.Skip_LEB128(&offset);
168            break;
169
170          case DW_FORM_indirect:
171            form_is_indirect = true;
172            form = data.GetULEB128(&offset);
173            break;
174
175          case DW_FORM_strp:
176          case DW_FORM_sec_offset:
177            data.GetU32(&offset);
178            break;
179
180          case DW_FORM_implicit_const:
181            form_size = 0;
182            break;
183
184          default:
185            *offset_ptr = m_offset;
186            return false;
187          }
188          offset += form_size;
189
190        } while (form_is_indirect);
191      }
192    }
193    *offset_ptr = offset;
194    return true;
195  } else {
196    m_tag = llvm::dwarf::DW_TAG_null;
197    m_has_children = false;
198    return true; // NULL debug tag entry
199  }
200
201  return false;
202}
203
204static DWARFRangeList GetRangesOrReportError(DWARFUnit &unit,
205                                             const DWARFDebugInfoEntry &die,
206                                             const DWARFFormValue &value) {
207  llvm::Expected<DWARFRangeList> expected_ranges =
208      (value.Form() == DW_FORM_rnglistx)
209          ? unit.FindRnglistFromIndex(value.Unsigned())
210          : unit.FindRnglistFromOffset(value.Unsigned());
211  if (expected_ranges)
212    return std::move(*expected_ranges);
213  unit.GetSymbolFileDWARF().GetObjectFile()->GetModule()->ReportError(
214      "{0x%8.8x}: DIE has DW_AT_ranges(0x%" PRIx64 ") attribute, but "
215      "range extraction failed (%s), please file a bug "
216      "and attach the file at the start of this error message",
217      die.GetOffset(), value.Unsigned(),
218      toString(expected_ranges.takeError()).c_str());
219  return DWARFRangeList();
220}
221
222// GetDIENamesAndRanges
223//
224// Gets the valid address ranges for a given DIE by looking for a
225// DW_AT_low_pc/DW_AT_high_pc pair, DW_AT_entry_pc, or DW_AT_ranges attributes.
226bool DWARFDebugInfoEntry::GetDIENamesAndRanges(
227    DWARFUnit *cu, const char *&name, const char *&mangled,
228    DWARFRangeList &ranges, int &decl_file, int &decl_line, int &decl_column,
229    int &call_file, int &call_line, int &call_column,
230    DWARFExpression *frame_base) const {
231  dw_addr_t lo_pc = LLDB_INVALID_ADDRESS;
232  dw_addr_t hi_pc = LLDB_INVALID_ADDRESS;
233  std::vector<DWARFDIE> dies;
234  bool set_frame_base_loclist_addr = false;
235
236  const auto *abbrevDecl = GetAbbreviationDeclarationPtr(cu);
237
238  SymbolFileDWARF &dwarf = cu->GetSymbolFileDWARF();
239  lldb::ModuleSP module = dwarf.GetObjectFile()->GetModule();
240
241  if (abbrevDecl) {
242    const DWARFDataExtractor &data = cu->GetData();
243    lldb::offset_t offset = GetFirstAttributeOffset();
244
245    if (!data.ValidOffset(offset))
246      return false;
247
248    const uint32_t numAttributes = abbrevDecl->NumAttributes();
249    bool do_offset = false;
250
251    for (uint32_t i = 0; i < numAttributes; ++i) {
252      DWARFFormValue form_value(cu);
253      dw_attr_t attr;
254      abbrevDecl->GetAttrAndFormValueByIndex(i, attr, form_value);
255
256      if (form_value.ExtractValue(data, &offset)) {
257        switch (attr) {
258        case DW_AT_low_pc:
259          lo_pc = form_value.Address();
260
261          if (do_offset)
262            hi_pc += lo_pc;
263          do_offset = false;
264          break;
265
266        case DW_AT_entry_pc:
267          lo_pc = form_value.Address();
268          break;
269
270        case DW_AT_high_pc:
271          if (form_value.Form() == DW_FORM_addr ||
272              form_value.Form() == DW_FORM_addrx ||
273              form_value.Form() == DW_FORM_GNU_addr_index) {
274            hi_pc = form_value.Address();
275          } else {
276            hi_pc = form_value.Unsigned();
277            if (lo_pc == LLDB_INVALID_ADDRESS)
278              do_offset = hi_pc != LLDB_INVALID_ADDRESS;
279            else
280              hi_pc += lo_pc; // DWARF 4 introduces <offset-from-lo-pc> to save
281                              // on relocations
282          }
283          break;
284
285        case DW_AT_ranges:
286          ranges = GetRangesOrReportError(*cu, *this, form_value);
287          break;
288
289        case DW_AT_name:
290          if (name == nullptr)
291            name = form_value.AsCString();
292          break;
293
294        case DW_AT_MIPS_linkage_name:
295        case DW_AT_linkage_name:
296          if (mangled == nullptr)
297            mangled = form_value.AsCString();
298          break;
299
300        case DW_AT_abstract_origin:
301          dies.push_back(form_value.Reference());
302          break;
303
304        case DW_AT_specification:
305          dies.push_back(form_value.Reference());
306          break;
307
308        case DW_AT_decl_file:
309          if (decl_file == 0)
310            decl_file = form_value.Unsigned();
311          break;
312
313        case DW_AT_decl_line:
314          if (decl_line == 0)
315            decl_line = form_value.Unsigned();
316          break;
317
318        case DW_AT_decl_column:
319          if (decl_column == 0)
320            decl_column = form_value.Unsigned();
321          break;
322
323        case DW_AT_call_file:
324          if (call_file == 0)
325            call_file = form_value.Unsigned();
326          break;
327
328        case DW_AT_call_line:
329          if (call_line == 0)
330            call_line = form_value.Unsigned();
331          break;
332
333        case DW_AT_call_column:
334          if (call_column == 0)
335            call_column = form_value.Unsigned();
336          break;
337
338        case DW_AT_frame_base:
339          if (frame_base) {
340            if (form_value.BlockData()) {
341              uint32_t block_offset =
342                  form_value.BlockData() - data.GetDataStart();
343              uint32_t block_length = form_value.Unsigned();
344              *frame_base = DWARFExpression(
345                  module, DataExtractor(data, block_offset, block_length), cu);
346            } else {
347              DataExtractor data = cu->GetLocationData();
348              const dw_offset_t offset = form_value.Unsigned();
349              if (data.ValidOffset(offset)) {
350                data = DataExtractor(data, offset, data.GetByteSize() - offset);
351                *frame_base = DWARFExpression(module, data, cu);
352                if (lo_pc != LLDB_INVALID_ADDRESS) {
353                  assert(lo_pc >= cu->GetBaseAddress());
354                  frame_base->SetLocationListAddresses(cu->GetBaseAddress(),
355                                                       lo_pc);
356                } else {
357                  set_frame_base_loclist_addr = true;
358                }
359              }
360            }
361          }
362          break;
363
364        default:
365          break;
366        }
367      }
368    }
369  }
370
371  if (ranges.IsEmpty()) {
372    if (lo_pc != LLDB_INVALID_ADDRESS) {
373      if (hi_pc != LLDB_INVALID_ADDRESS && hi_pc > lo_pc)
374        ranges.Append(DWARFRangeList::Entry(lo_pc, hi_pc - lo_pc));
375      else
376        ranges.Append(DWARFRangeList::Entry(lo_pc, 0));
377    }
378  }
379
380  if (set_frame_base_loclist_addr) {
381    dw_addr_t lowest_range_pc = ranges.GetMinRangeBase(0);
382    assert(lowest_range_pc >= cu->GetBaseAddress());
383    frame_base->SetLocationListAddresses(cu->GetBaseAddress(), lowest_range_pc);
384  }
385
386  if (ranges.IsEmpty() || name == nullptr || mangled == nullptr) {
387    for (const DWARFDIE &die : dies) {
388      if (die) {
389        die.GetDIE()->GetDIENamesAndRanges(die.GetCU(), name, mangled, ranges,
390                                           decl_file, decl_line, decl_column,
391                                           call_file, call_line, call_column);
392      }
393    }
394  }
395  return !ranges.IsEmpty();
396}
397
398// Dump
399//
400// Dumps a debug information entry and all of it's attributes to the specified
401// stream.
402void DWARFDebugInfoEntry::Dump(const DWARFUnit *cu, Stream &s,
403                               uint32_t recurse_depth) const {
404  const DWARFDataExtractor &data = cu->GetData();
405  lldb::offset_t offset = m_offset;
406
407  if (data.ValidOffset(offset)) {
408    dw_uleb128_t abbrCode = data.GetULEB128(&offset);
409
410    s.Printf("\n0x%8.8x: ", m_offset);
411    s.Indent();
412    if (abbrCode != m_abbr_idx) {
413      s.Printf("error: DWARF has been modified\n");
414    } else if (abbrCode) {
415      const auto *abbrevDecl = GetAbbreviationDeclarationPtr(cu);
416      if (abbrevDecl) {
417        s.PutCString(DW_TAG_value_to_name(abbrevDecl->Tag()));
418        s.Printf(" [%u] %c\n", abbrCode, abbrevDecl->HasChildren() ? '*' : ' ');
419
420        // Dump all data in the .debug_info/.debug_types for the attributes
421        const uint32_t numAttributes = abbrevDecl->NumAttributes();
422        for (uint32_t i = 0; i < numAttributes; ++i) {
423          DWARFFormValue form_value(cu);
424          dw_attr_t attr;
425          abbrevDecl->GetAttrAndFormValueByIndex(i, attr, form_value);
426
427          DumpAttribute(cu, data, &offset, s, attr, form_value);
428        }
429
430        const DWARFDebugInfoEntry *child = GetFirstChild();
431        if (recurse_depth > 0 && child) {
432          s.IndentMore();
433
434          while (child) {
435            child->Dump(cu, s, recurse_depth - 1);
436            child = child->GetSibling();
437          }
438          s.IndentLess();
439        }
440      } else
441        s.Printf("Abbreviation code note found in 'debug_abbrev' class for "
442                 "code: %u\n",
443                 abbrCode);
444    } else {
445      s.Printf("NULL\n");
446    }
447  }
448}
449
450// DumpAttribute
451//
452// Dumps a debug information entry attribute along with it's form. Any special
453// display of attributes is done (disassemble location lists, show enumeration
454// values for attributes, etc).
455void DWARFDebugInfoEntry::DumpAttribute(
456    const DWARFUnit *cu, const DWARFDataExtractor &data,
457    lldb::offset_t *offset_ptr, Stream &s, dw_attr_t attr,
458    DWARFFormValue &form_value) {
459  bool show_form = s.GetFlags().Test(DWARFDebugInfo::eDumpFlag_ShowForm);
460
461  s.Printf("            ");
462  s.Indent(DW_AT_value_to_name(attr));
463
464  if (show_form) {
465    s.Printf("[%s", DW_FORM_value_to_name(form_value.Form()));
466  }
467
468  if (!form_value.ExtractValue(data, offset_ptr))
469    return;
470
471  if (show_form) {
472    if (form_value.Form() == DW_FORM_indirect) {
473      s.Printf(" [%s]", DW_FORM_value_to_name(form_value.Form()));
474    }
475
476    s.PutCString("] ");
477  }
478
479  s.PutCString("( ");
480
481  // Check to see if we have any special attribute formatters
482  switch (attr) {
483  case DW_AT_stmt_list:
484    s.Printf("0x%8.8" PRIx64, form_value.Unsigned());
485    break;
486
487  case DW_AT_language:
488    s.PutCString(DW_LANG_value_to_name(form_value.Unsigned()));
489    break;
490
491  case DW_AT_encoding:
492    s.PutCString(DW_ATE_value_to_name(form_value.Unsigned()));
493    break;
494
495  case DW_AT_frame_base:
496  case DW_AT_location:
497  case DW_AT_data_member_location: {
498    const uint8_t *blockData = form_value.BlockData();
499    if (blockData) {
500      // Location description is inlined in data in the form value
501      DWARFDataExtractor locationData(data,
502                                      (*offset_ptr) - form_value.Unsigned(),
503                                      form_value.Unsigned());
504      DWARFExpression::PrintDWARFExpression(
505          s, locationData, DWARFUnit::GetAddressByteSize(cu), 4, false);
506    } else {
507      // We have a location list offset as the value that is the offset into
508      // the .debug_loc section that describes the value over it's lifetime
509      uint64_t debug_loc_offset = form_value.Unsigned();
510      DWARFExpression::PrintDWARFLocationList(s, cu, cu->GetLocationData(),
511                                              debug_loc_offset);
512    }
513  } break;
514
515  case DW_AT_abstract_origin:
516  case DW_AT_specification: {
517    DWARFDIE abstract_die = form_value.Reference();
518    form_value.Dump(s);
519    //  *ostrm_ptr << HEX32 << abstract_die.GetOffset() << " ( ";
520    abstract_die.GetName(s);
521  } break;
522
523  case DW_AT_type: {
524    DWARFDIE type_die = form_value.Reference();
525    s.PutCString(" ( ");
526    type_die.AppendTypeName(s);
527    s.PutCString(" )");
528  } break;
529
530  default:
531    break;
532  }
533
534  s.PutCString(" )\n");
535}
536
537// Get all attribute values for a given DIE, including following any
538// specification or abstract origin attributes and including those in the
539// results. Any duplicate attributes will have the first instance take
540// precedence (this can happen for declaration attributes).
541size_t DWARFDebugInfoEntry::GetAttributes(
542    const DWARFUnit *cu, DWARFAttributes &attributes,
543    uint32_t curr_depth) const {
544  const auto *abbrevDecl = GetAbbreviationDeclarationPtr(cu);
545  if (abbrevDecl) {
546    const DWARFDataExtractor &data = cu->GetData();
547    lldb::offset_t offset = GetFirstAttributeOffset();
548
549    const uint32_t num_attributes = abbrevDecl->NumAttributes();
550    for (uint32_t i = 0; i < num_attributes; ++i) {
551      DWARFFormValue form_value(cu);
552      dw_attr_t attr;
553      abbrevDecl->GetAttrAndFormValueByIndex(i, attr, form_value);
554      const dw_form_t form = form_value.Form();
555
556      // If we are tracking down DW_AT_specification or DW_AT_abstract_origin
557      // attributes, the depth will be non-zero. We need to omit certain
558      // attributes that don't make sense.
559      switch (attr) {
560      case DW_AT_sibling:
561      case DW_AT_declaration:
562        if (curr_depth > 0) {
563          // This attribute doesn't make sense when combined with the DIE that
564          // references this DIE. We know a DIE is referencing this DIE because
565          // curr_depth is not zero
566          break;
567        }
568        LLVM_FALLTHROUGH;
569      default:
570        attributes.Append(cu, offset, attr, form);
571        break;
572      }
573
574      if ((attr == DW_AT_specification) || (attr == DW_AT_abstract_origin)) {
575        if (form_value.ExtractValue(data, &offset)) {
576          DWARFDIE spec_die = form_value.Reference();
577          if (spec_die)
578            spec_die.GetAttributes(attributes, curr_depth + 1);
579        }
580      } else {
581        llvm::Optional<uint8_t> fixed_skip_size = DWARFFormValue::GetFixedSize(form, cu);
582        if (fixed_skip_size)
583          offset += *fixed_skip_size;
584        else
585          DWARFFormValue::SkipValue(form, data, &offset, cu);
586      }
587    }
588  } else {
589    attributes.Clear();
590  }
591  return attributes.Size();
592}
593
594// GetAttributeValue
595//
596// Get the value of an attribute and return the .debug_info or .debug_types
597// offset of the attribute if it was properly extracted into form_value,
598// or zero if we fail since an offset of zero is invalid for an attribute (it
599// would be a compile unit header).
600dw_offset_t DWARFDebugInfoEntry::GetAttributeValue(
601    const DWARFUnit *cu, const dw_attr_t attr, DWARFFormValue &form_value,
602    dw_offset_t *end_attr_offset_ptr,
603    bool check_specification_or_abstract_origin) const {
604  if (const auto *abbrevDecl = GetAbbreviationDeclarationPtr(cu)) {
605    uint32_t attr_idx = abbrevDecl->FindAttributeIndex(attr);
606
607    if (attr_idx != DW_INVALID_INDEX) {
608      const DWARFDataExtractor &data = cu->GetData();
609      lldb::offset_t offset = GetFirstAttributeOffset();
610
611      uint32_t idx = 0;
612      while (idx < attr_idx)
613        DWARFFormValue::SkipValue(abbrevDecl->GetFormByIndex(idx++),
614                                  data, &offset, cu);
615
616      const dw_offset_t attr_offset = offset;
617      form_value.SetUnit(cu);
618      form_value.SetForm(abbrevDecl->GetFormByIndex(idx));
619      if (form_value.ExtractValue(data, &offset)) {
620        if (end_attr_offset_ptr)
621          *end_attr_offset_ptr = offset;
622        return attr_offset;
623      }
624    }
625  }
626
627  if (check_specification_or_abstract_origin) {
628    if (GetAttributeValue(cu, DW_AT_specification, form_value)) {
629      DWARFDIE die = form_value.Reference();
630      if (die) {
631        dw_offset_t die_offset = die.GetDIE()->GetAttributeValue(
632            die.GetCU(), attr, form_value, end_attr_offset_ptr, false);
633        if (die_offset)
634          return die_offset;
635      }
636    }
637
638    if (GetAttributeValue(cu, DW_AT_abstract_origin, form_value)) {
639      DWARFDIE die = form_value.Reference();
640      if (die) {
641        dw_offset_t die_offset = die.GetDIE()->GetAttributeValue(
642            die.GetCU(), attr, form_value, end_attr_offset_ptr, false);
643        if (die_offset)
644          return die_offset;
645      }
646    }
647  }
648  return 0;
649}
650
651// GetAttributeValueAsString
652//
653// Get the value of an attribute as a string return it. The resulting pointer
654// to the string data exists within the supplied SymbolFileDWARF and will only
655// be available as long as the SymbolFileDWARF is still around and it's content
656// doesn't change.
657const char *DWARFDebugInfoEntry::GetAttributeValueAsString(
658    const DWARFUnit *cu, const dw_attr_t attr, const char *fail_value,
659    bool check_specification_or_abstract_origin) const {
660  DWARFFormValue form_value;
661  if (GetAttributeValue(cu, attr, form_value, nullptr,
662                        check_specification_or_abstract_origin))
663    return form_value.AsCString();
664  return fail_value;
665}
666
667// GetAttributeValueAsUnsigned
668//
669// Get the value of an attribute as unsigned and return it.
670uint64_t DWARFDebugInfoEntry::GetAttributeValueAsUnsigned(
671    const DWARFUnit *cu, const dw_attr_t attr, uint64_t fail_value,
672    bool check_specification_or_abstract_origin) const {
673  DWARFFormValue form_value;
674  if (GetAttributeValue(cu, attr, form_value, nullptr,
675                        check_specification_or_abstract_origin))
676    return form_value.Unsigned();
677  return fail_value;
678}
679
680// GetAttributeValueAsReference
681//
682// Get the value of an attribute as reference and fix up and compile unit
683// relative offsets as needed.
684DWARFDIE DWARFDebugInfoEntry::GetAttributeValueAsReference(
685    const DWARFUnit *cu, const dw_attr_t attr,
686    bool check_specification_or_abstract_origin) const {
687  DWARFFormValue form_value;
688  if (GetAttributeValue(cu, attr, form_value, nullptr,
689                        check_specification_or_abstract_origin))
690    return form_value.Reference();
691  return {};
692}
693
694uint64_t DWARFDebugInfoEntry::GetAttributeValueAsAddress(
695    const DWARFUnit *cu, const dw_attr_t attr, uint64_t fail_value,
696    bool check_specification_or_abstract_origin) const {
697  DWARFFormValue form_value;
698  if (GetAttributeValue(cu, attr, form_value, nullptr,
699                        check_specification_or_abstract_origin))
700    return form_value.Address();
701  return fail_value;
702}
703
704// GetAttributeHighPC
705//
706// Get the hi_pc, adding hi_pc to lo_pc when specified as an <offset-from-low-
707// pc>.
708//
709// Returns the hi_pc or fail_value.
710dw_addr_t DWARFDebugInfoEntry::GetAttributeHighPC(
711    const DWARFUnit *cu, dw_addr_t lo_pc, uint64_t fail_value,
712    bool check_specification_or_abstract_origin) const {
713  DWARFFormValue form_value;
714  if (GetAttributeValue(cu, DW_AT_high_pc, form_value, nullptr,
715                        check_specification_or_abstract_origin)) {
716    dw_form_t form = form_value.Form();
717    if (form == DW_FORM_addr || form == DW_FORM_addrx ||
718        form == DW_FORM_GNU_addr_index)
719      return form_value.Address();
720
721    // DWARF4 can specify the hi_pc as an <offset-from-lowpc>
722    return lo_pc + form_value.Unsigned();
723  }
724  return fail_value;
725}
726
727// GetAttributeAddressRange
728//
729// Get the lo_pc and hi_pc, adding hi_pc to lo_pc when specified as an <offset-
730// from-low-pc>.
731//
732// Returns true or sets lo_pc and hi_pc to fail_value.
733bool DWARFDebugInfoEntry::GetAttributeAddressRange(
734    const DWARFUnit *cu, dw_addr_t &lo_pc, dw_addr_t &hi_pc,
735    uint64_t fail_value, bool check_specification_or_abstract_origin) const {
736  lo_pc = GetAttributeValueAsAddress(cu, DW_AT_low_pc, fail_value,
737                                     check_specification_or_abstract_origin);
738  if (lo_pc != fail_value) {
739    hi_pc = GetAttributeHighPC(cu, lo_pc, fail_value,
740                               check_specification_or_abstract_origin);
741    if (hi_pc != fail_value)
742      return true;
743  }
744  lo_pc = fail_value;
745  hi_pc = fail_value;
746  return false;
747}
748
749size_t DWARFDebugInfoEntry::GetAttributeAddressRanges(
750    DWARFUnit *cu, DWARFRangeList &ranges, bool check_hi_lo_pc,
751    bool check_specification_or_abstract_origin) const {
752  ranges.Clear();
753
754  DWARFFormValue form_value;
755  if (GetAttributeValue(cu, DW_AT_ranges, form_value)) {
756    ranges = GetRangesOrReportError(*cu, *this, form_value);
757  } else if (check_hi_lo_pc) {
758    dw_addr_t lo_pc = LLDB_INVALID_ADDRESS;
759    dw_addr_t hi_pc = LLDB_INVALID_ADDRESS;
760    if (GetAttributeAddressRange(cu, lo_pc, hi_pc, LLDB_INVALID_ADDRESS,
761                                 check_specification_or_abstract_origin)) {
762      if (lo_pc < hi_pc)
763        ranges.Append(DWARFRangeList::Entry(lo_pc, hi_pc - lo_pc));
764    }
765  }
766  return ranges.GetSize();
767}
768
769// GetName
770//
771// Get value of the DW_AT_name attribute and return it if one exists, else
772// return NULL.
773const char *DWARFDebugInfoEntry::GetName(const DWARFUnit *cu) const {
774  return GetAttributeValueAsString(cu, DW_AT_name, nullptr, true);
775}
776
777// GetMangledName
778//
779// Get value of the DW_AT_MIPS_linkage_name attribute and return it if one
780// exists, else return the value of the DW_AT_name attribute
781const char *
782DWARFDebugInfoEntry::GetMangledName(const DWARFUnit *cu,
783                                    bool substitute_name_allowed) const {
784  const char *name = nullptr;
785
786  name = GetAttributeValueAsString(cu, DW_AT_MIPS_linkage_name, nullptr, true);
787  if (name)
788    return name;
789
790  name = GetAttributeValueAsString(cu, DW_AT_linkage_name, nullptr, true);
791  if (name)
792    return name;
793
794  if (!substitute_name_allowed)
795    return nullptr;
796
797  name = GetAttributeValueAsString(cu, DW_AT_name, nullptr, true);
798  return name;
799}
800
801// GetPubname
802//
803// Get value the name for a DIE as it should appear for a .debug_pubnames or
804// .debug_pubtypes section.
805const char *DWARFDebugInfoEntry::GetPubname(const DWARFUnit *cu) const {
806  const char *name = nullptr;
807  if (!cu)
808    return name;
809
810  name = GetAttributeValueAsString(cu, DW_AT_MIPS_linkage_name, nullptr, true);
811  if (name)
812    return name;
813
814  name = GetAttributeValueAsString(cu, DW_AT_linkage_name, nullptr, true);
815  if (name)
816    return name;
817
818  name = GetAttributeValueAsString(cu, DW_AT_name, nullptr, true);
819  return name;
820}
821
822// BuildAddressRangeTable
823void DWARFDebugInfoEntry::BuildAddressRangeTable(
824    const DWARFUnit *cu, DWARFDebugAranges *debug_aranges) const {
825  if (m_tag) {
826    if (m_tag == DW_TAG_subprogram) {
827      dw_addr_t lo_pc = LLDB_INVALID_ADDRESS;
828      dw_addr_t hi_pc = LLDB_INVALID_ADDRESS;
829      if (GetAttributeAddressRange(cu, lo_pc, hi_pc, LLDB_INVALID_ADDRESS)) {
830        /// printf("BuildAddressRangeTable() 0x%8.8x: %30s: [0x%8.8x -
831        /// 0x%8.8x)\n", m_offset, DW_TAG_value_to_name(tag), lo_pc, hi_pc);
832        debug_aranges->AppendRange(cu->GetOffset(), lo_pc, hi_pc);
833      }
834    }
835
836    const DWARFDebugInfoEntry *child = GetFirstChild();
837    while (child) {
838      child->BuildAddressRangeTable(cu, debug_aranges);
839      child = child->GetSibling();
840    }
841  }
842}
843
844// BuildFunctionAddressRangeTable
845//
846// This function is very similar to the BuildAddressRangeTable function except
847// that the actual DIE offset for the function is placed in the table instead
848// of the compile unit offset (which is the way the standard .debug_aranges
849// section does it).
850void DWARFDebugInfoEntry::BuildFunctionAddressRangeTable(
851    const DWARFUnit *cu, DWARFDebugAranges *debug_aranges) const {
852  if (m_tag) {
853    if (m_tag == DW_TAG_subprogram) {
854      dw_addr_t lo_pc = LLDB_INVALID_ADDRESS;
855      dw_addr_t hi_pc = LLDB_INVALID_ADDRESS;
856      if (GetAttributeAddressRange(cu, lo_pc, hi_pc, LLDB_INVALID_ADDRESS)) {
857        //  printf("BuildAddressRangeTable() 0x%8.8x: [0x%16.16" PRIx64 " -
858        //  0x%16.16" PRIx64 ")\n", m_offset, lo_pc, hi_pc); // DEBUG ONLY
859        debug_aranges->AppendRange(GetOffset(), lo_pc, hi_pc);
860      }
861    }
862
863    const DWARFDebugInfoEntry *child = GetFirstChild();
864    while (child) {
865      child->BuildFunctionAddressRangeTable(cu, debug_aranges);
866      child = child->GetSibling();
867    }
868  }
869}
870
871void DWARFDebugInfoEntry::GetDWARFDeclContext(
872    DWARFUnit *cu, DWARFDeclContext &dwarf_decl_ctx) const {
873  const dw_tag_t tag = Tag();
874  if (tag != DW_TAG_compile_unit && tag != DW_TAG_partial_unit) {
875    dwarf_decl_ctx.AppendDeclContext(tag, GetName(cu));
876    DWARFDIE parent_decl_ctx_die = GetParentDeclContextDIE(cu);
877    if (parent_decl_ctx_die && parent_decl_ctx_die.GetDIE() != this) {
878      if (parent_decl_ctx_die.Tag() != DW_TAG_compile_unit &&
879          parent_decl_ctx_die.Tag() != DW_TAG_partial_unit)
880        parent_decl_ctx_die.GetDIE()->GetDWARFDeclContext(
881            parent_decl_ctx_die.GetCU(), dwarf_decl_ctx);
882    }
883  }
884}
885
886DWARFDIE
887DWARFDebugInfoEntry::GetParentDeclContextDIE(DWARFUnit *cu) const {
888  DWARFAttributes attributes;
889  GetAttributes(cu, attributes);
890  return GetParentDeclContextDIE(cu, attributes);
891}
892
893DWARFDIE
894DWARFDebugInfoEntry::GetParentDeclContextDIE(
895    DWARFUnit *cu, const DWARFAttributes &attributes) const {
896  DWARFDIE die(cu, const_cast<DWARFDebugInfoEntry *>(this));
897
898  while (die) {
899    // If this is the original DIE that we are searching for a declaration for,
900    // then don't look in the cache as we don't want our own decl context to be
901    // our decl context...
902    if (die.GetDIE() != this) {
903      switch (die.Tag()) {
904      case DW_TAG_compile_unit:
905      case DW_TAG_partial_unit:
906      case DW_TAG_namespace:
907      case DW_TAG_structure_type:
908      case DW_TAG_union_type:
909      case DW_TAG_class_type:
910        return die;
911
912      default:
913        break;
914      }
915    }
916
917    DWARFDIE spec_die = attributes.FormValueAsReference(DW_AT_specification);
918    if (spec_die) {
919      DWARFDIE decl_ctx_die = spec_die.GetParentDeclContextDIE();
920      if (decl_ctx_die)
921        return decl_ctx_die;
922    }
923
924    DWARFDIE abs_die = attributes.FormValueAsReference(DW_AT_abstract_origin);
925    if (abs_die) {
926      DWARFDIE decl_ctx_die = abs_die.GetParentDeclContextDIE();
927      if (decl_ctx_die)
928        return decl_ctx_die;
929    }
930
931    die = die.GetParent();
932  }
933  return DWARFDIE();
934}
935
936const char *DWARFDebugInfoEntry::GetQualifiedName(DWARFUnit *cu,
937                                                  std::string &storage) const {
938  DWARFAttributes attributes;
939  GetAttributes(cu, attributes);
940  return GetQualifiedName(cu, attributes, storage);
941}
942
943const char *
944DWARFDebugInfoEntry::GetQualifiedName(DWARFUnit *cu,
945                                      const DWARFAttributes &attributes,
946                                      std::string &storage) const {
947
948  const char *name = GetName(cu);
949
950  if (name) {
951    DWARFDIE parent_decl_ctx_die = GetParentDeclContextDIE(cu);
952    storage.clear();
953    // TODO: change this to get the correct decl context parent....
954    while (parent_decl_ctx_die) {
955      const dw_tag_t parent_tag = parent_decl_ctx_die.Tag();
956      switch (parent_tag) {
957      case DW_TAG_namespace: {
958        const char *namespace_name = parent_decl_ctx_die.GetName();
959        if (namespace_name) {
960          storage.insert(0, "::");
961          storage.insert(0, namespace_name);
962        } else {
963          storage.insert(0, "(anonymous namespace)::");
964        }
965        parent_decl_ctx_die = parent_decl_ctx_die.GetParentDeclContextDIE();
966      } break;
967
968      case DW_TAG_class_type:
969      case DW_TAG_structure_type:
970      case DW_TAG_union_type: {
971        const char *class_union_struct_name = parent_decl_ctx_die.GetName();
972
973        if (class_union_struct_name) {
974          storage.insert(0, "::");
975          storage.insert(0, class_union_struct_name);
976        }
977        parent_decl_ctx_die = parent_decl_ctx_die.GetParentDeclContextDIE();
978      } break;
979
980      default:
981        parent_decl_ctx_die.Clear();
982        break;
983      }
984    }
985
986    if (storage.empty())
987      storage.append("::");
988
989    storage.append(name);
990  }
991  if (storage.empty())
992    return nullptr;
993  return storage.c_str();
994}
995
996bool DWARFDebugInfoEntry::LookupAddress(const dw_addr_t address, DWARFUnit *cu,
997                                        DWARFDebugInfoEntry **function_die,
998                                        DWARFDebugInfoEntry **block_die) {
999  bool found_address = false;
1000  if (m_tag) {
1001    bool check_children = false;
1002    bool match_addr_range = false;
1003    //  printf("0x%8.8x: %30s: address = 0x%8.8x - ", m_offset,
1004    //  DW_TAG_value_to_name(tag), address);
1005    switch (m_tag) {
1006    case DW_TAG_array_type:
1007      break;
1008    case DW_TAG_class_type:
1009      check_children = true;
1010      break;
1011    case DW_TAG_entry_point:
1012    case DW_TAG_enumeration_type:
1013    case DW_TAG_formal_parameter:
1014    case DW_TAG_imported_declaration:
1015    case DW_TAG_label:
1016      break;
1017    case DW_TAG_lexical_block:
1018      check_children = true;
1019      match_addr_range = true;
1020      break;
1021    case DW_TAG_member:
1022    case DW_TAG_pointer_type:
1023    case DW_TAG_reference_type:
1024      break;
1025    case DW_TAG_compile_unit:
1026      match_addr_range = true;
1027      break;
1028    case DW_TAG_string_type:
1029      break;
1030    case DW_TAG_structure_type:
1031      check_children = true;
1032      break;
1033    case DW_TAG_subroutine_type:
1034    case DW_TAG_typedef:
1035    case DW_TAG_union_type:
1036    case DW_TAG_unspecified_parameters:
1037    case DW_TAG_variant:
1038      break;
1039    case DW_TAG_common_block:
1040      check_children = true;
1041      break;
1042    case DW_TAG_common_inclusion:
1043    case DW_TAG_inheritance:
1044      break;
1045    case DW_TAG_inlined_subroutine:
1046      check_children = true;
1047      match_addr_range = true;
1048      break;
1049    case DW_TAG_module:
1050      match_addr_range = true;
1051      break;
1052    case DW_TAG_ptr_to_member_type:
1053    case DW_TAG_set_type:
1054    case DW_TAG_subrange_type:
1055    case DW_TAG_with_stmt:
1056    case DW_TAG_access_declaration:
1057    case DW_TAG_base_type:
1058      break;
1059    case DW_TAG_catch_block:
1060      match_addr_range = true;
1061      break;
1062    case DW_TAG_const_type:
1063    case DW_TAG_constant:
1064    case DW_TAG_enumerator:
1065    case DW_TAG_file_type:
1066    case DW_TAG_friend:
1067    case DW_TAG_namelist:
1068    case DW_TAG_namelist_item:
1069    case DW_TAG_packed_type:
1070      break;
1071    case DW_TAG_subprogram:
1072      match_addr_range = true;
1073      break;
1074    case DW_TAG_template_type_parameter:
1075    case DW_TAG_template_value_parameter:
1076    case DW_TAG_GNU_template_parameter_pack:
1077    case DW_TAG_thrown_type:
1078      break;
1079    case DW_TAG_try_block:
1080      match_addr_range = true;
1081      break;
1082    case DW_TAG_variant_part:
1083    case DW_TAG_variable:
1084    case DW_TAG_volatile_type:
1085    case DW_TAG_dwarf_procedure:
1086    case DW_TAG_restrict_type:
1087    case DW_TAG_interface_type:
1088      break;
1089    case DW_TAG_namespace:
1090      check_children = true;
1091      break;
1092    case DW_TAG_imported_module:
1093    case DW_TAG_unspecified_type:
1094      break;
1095    case DW_TAG_partial_unit:
1096      match_addr_range = true;
1097      break;
1098    case DW_TAG_imported_unit:
1099    case DW_TAG_shared_type:
1100    default:
1101      break;
1102    }
1103
1104    if (match_addr_range) {
1105      dw_addr_t lo_pc =
1106          GetAttributeValueAsAddress(cu, DW_AT_low_pc, LLDB_INVALID_ADDRESS);
1107      if (lo_pc != LLDB_INVALID_ADDRESS) {
1108        dw_addr_t hi_pc = GetAttributeHighPC(cu, lo_pc, LLDB_INVALID_ADDRESS);
1109        if (hi_pc != LLDB_INVALID_ADDRESS) {
1110          //  printf("\n0x%8.8x: %30s: address = 0x%8.8x  [0x%8.8x - 0x%8.8x) ",
1111          //  m_offset, DW_TAG_value_to_name(tag), address, lo_pc, hi_pc);
1112          if ((lo_pc <= address) && (address < hi_pc)) {
1113            found_address = true;
1114            //  puts("***MATCH***");
1115            switch (m_tag) {
1116            case DW_TAG_compile_unit: // File
1117            case DW_TAG_partial_unit: // File
1118              check_children =
1119                  ((function_die != nullptr) || (block_die != nullptr));
1120              break;
1121
1122            case DW_TAG_subprogram: // Function
1123              if (function_die)
1124                *function_die = this;
1125              check_children = (block_die != nullptr);
1126              break;
1127
1128            case DW_TAG_inlined_subroutine: // Inlined Function
1129            case DW_TAG_lexical_block:      // Block { } in code
1130              if (block_die) {
1131                *block_die = this;
1132                check_children = true;
1133              }
1134              break;
1135
1136            default:
1137              check_children = true;
1138              break;
1139            }
1140          }
1141        } else {
1142          // Compile units may not have a valid high/low pc when there
1143          // are address gaps in subroutines so we must always search
1144          // if there is no valid high and low PC.
1145          check_children =
1146              (m_tag == DW_TAG_compile_unit || m_tag == DW_TAG_partial_unit) &&
1147              ((function_die != nullptr) || (block_die != nullptr));
1148        }
1149      } else {
1150        DWARFRangeList ranges;
1151        if (GetAttributeAddressRanges(cu, ranges, /*check_hi_lo_pc*/ false) &&
1152            ranges.FindEntryThatContains(address)) {
1153          found_address = true;
1154          //  puts("***MATCH***");
1155          switch (m_tag) {
1156          case DW_TAG_compile_unit: // File
1157          case DW_TAG_partial_unit: // File
1158              check_children =
1159                  ((function_die != nullptr) || (block_die != nullptr));
1160              break;
1161
1162          case DW_TAG_subprogram: // Function
1163            if (function_die)
1164              *function_die = this;
1165            check_children = (block_die != nullptr);
1166            break;
1167
1168          case DW_TAG_inlined_subroutine: // Inlined Function
1169          case DW_TAG_lexical_block:      // Block { } in code
1170            if (block_die) {
1171              *block_die = this;
1172              check_children = true;
1173            }
1174            break;
1175
1176          default:
1177            check_children = true;
1178            break;
1179          }
1180        } else {
1181          check_children = false;
1182        }
1183      }
1184    }
1185
1186    if (check_children) {
1187      //  printf("checking children\n");
1188      DWARFDebugInfoEntry *child = GetFirstChild();
1189      while (child) {
1190        if (child->LookupAddress(address, cu, function_die, block_die))
1191          return true;
1192        child = child->GetSibling();
1193      }
1194    }
1195  }
1196  return found_address;
1197}
1198
1199lldb::offset_t DWARFDebugInfoEntry::GetFirstAttributeOffset() const {
1200  return GetOffset() + llvm::getULEB128Size(m_abbr_idx);
1201}
1202
1203const DWARFAbbreviationDeclaration *
1204DWARFDebugInfoEntry::GetAbbreviationDeclarationPtr(const DWARFUnit *cu) const {
1205  if (cu) {
1206    const DWARFAbbreviationDeclarationSet *abbrev_set = cu->GetAbbreviations();
1207    if (abbrev_set)
1208      return abbrev_set->GetAbbreviationDeclaration(m_abbr_idx);
1209  }
1210  return nullptr;
1211}
1212
1213bool DWARFDebugInfoEntry::operator==(const DWARFDebugInfoEntry &rhs) const {
1214  return m_offset == rhs.m_offset && m_parent_idx == rhs.m_parent_idx &&
1215         m_sibling_idx == rhs.m_sibling_idx &&
1216         m_abbr_idx == rhs.m_abbr_idx && m_has_children == rhs.m_has_children &&
1217         m_tag == rhs.m_tag;
1218}
1219
1220bool DWARFDebugInfoEntry::operator!=(const DWARFDebugInfoEntry &rhs) const {
1221  return !(*this == rhs);
1222}
1223