1//===-- NameToDIE.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 "NameToDIE.h"
10#include "DWARFUnit.h"
11#include "lldb/Core/DataFileCache.h"
12#include "lldb/Symbol/ObjectFile.h"
13#include "lldb/Utility/ConstString.h"
14#include "lldb/Utility/DataEncoder.h"
15#include "lldb/Utility/DataExtractor.h"
16#include "lldb/Utility/RegularExpression.h"
17#include "lldb/Utility/Stream.h"
18#include "lldb/Utility/StreamString.h"
19#include <optional>
20
21using namespace lldb;
22using namespace lldb_private;
23
24void NameToDIE::Finalize() {
25  m_map.Sort(std::less<DIERef>());
26  m_map.SizeToFit();
27}
28
29void NameToDIE::Insert(ConstString name, const DIERef &die_ref) {
30  m_map.Append(name, die_ref);
31}
32
33bool NameToDIE::Find(ConstString name,
34                     llvm::function_ref<bool(DIERef ref)> callback) const {
35  for (const auto &entry : m_map.equal_range(name))
36    if (!callback(entry.value))
37      return false;
38  return true;
39}
40
41bool NameToDIE::Find(const RegularExpression &regex,
42                     llvm::function_ref<bool(DIERef ref)> callback) const {
43  for (const auto &entry : m_map)
44    if (regex.Execute(entry.cstring.GetCString())) {
45      if (!callback(entry.value))
46        return false;
47    }
48  return true;
49}
50
51void NameToDIE::FindAllEntriesForUnit(
52    DWARFUnit &s_unit, llvm::function_ref<bool(DIERef ref)> callback) const {
53  lldbassert(!s_unit.GetSymbolFileDWARF().GetDwoNum());
54  const DWARFUnit &ns_unit = s_unit.GetNonSkeletonUnit();
55  const uint32_t size = m_map.GetSize();
56  for (uint32_t i = 0; i < size; ++i) {
57    const DIERef &die_ref = m_map.GetValueAtIndexUnchecked(i);
58    if (ns_unit.GetSymbolFileDWARF().GetDwoNum() == die_ref.dwo_num() &&
59        ns_unit.GetDebugSection() == die_ref.section() &&
60        ns_unit.GetOffset() <= die_ref.die_offset() &&
61        die_ref.die_offset() < ns_unit.GetNextUnitOffset()) {
62      if (!callback(die_ref))
63        return;
64    }
65  }
66}
67
68void NameToDIE::Dump(Stream *s) {
69  const uint32_t size = m_map.GetSize();
70  for (uint32_t i = 0; i < size; ++i) {
71    s->Format("{0} \"{1}\"\n", m_map.GetValueAtIndexUnchecked(i),
72              m_map.GetCStringAtIndexUnchecked(i));
73  }
74}
75
76void NameToDIE::ForEach(
77    std::function<bool(ConstString name, const DIERef &die_ref)> const
78        &callback) const {
79  const uint32_t size = m_map.GetSize();
80  for (uint32_t i = 0; i < size; ++i) {
81    if (!callback(m_map.GetCStringAtIndexUnchecked(i),
82                  m_map.GetValueAtIndexUnchecked(i)))
83      break;
84  }
85}
86
87void NameToDIE::Append(const NameToDIE &other) {
88  const uint32_t size = other.m_map.GetSize();
89  for (uint32_t i = 0; i < size; ++i) {
90    m_map.Append(other.m_map.GetCStringAtIndexUnchecked(i),
91                 other.m_map.GetValueAtIndexUnchecked(i));
92  }
93}
94
95constexpr llvm::StringLiteral kIdentifierNameToDIE("N2DI");
96
97bool NameToDIE::Decode(const DataExtractor &data, lldb::offset_t *offset_ptr,
98                       const StringTableReader &strtab) {
99  m_map.Clear();
100  llvm::StringRef identifier((const char *)data.GetData(offset_ptr, 4), 4);
101  if (identifier != kIdentifierNameToDIE)
102    return false;
103  const uint32_t count = data.GetU32(offset_ptr);
104  m_map.Reserve(count);
105  for (uint32_t i = 0; i < count; ++i) {
106    llvm::StringRef str(strtab.Get(data.GetU32(offset_ptr)));
107    // No empty strings allowed in the name to DIE maps.
108    if (str.empty())
109      return false;
110    if (std::optional<DIERef> die_ref = DIERef::Decode(data, offset_ptr))
111      m_map.Append(ConstString(str), *die_ref);
112    else
113      return false;
114  }
115  // We must sort the UniqueCStringMap after decoding it since it is a vector
116  // of UniqueCStringMap::Entry objects which contain a ConstString and type T.
117  // ConstString objects are sorted by "const char *" and then type T and
118  // the "const char *" are point values that will depend on the order in which
119  // ConstString objects are created and in which of the 256 string pools they
120  // are created in. So after we decode all of the entries, we must sort the
121  // name map to ensure name lookups succeed. If we encode and decode within
122  // the same process we wouldn't need to sort, so unit testing didn't catch
123  // this issue when first checked in.
124  m_map.Sort(std::less<DIERef>());
125  return true;
126}
127
128void NameToDIE::Encode(DataEncoder &encoder, ConstStringTable &strtab) const {
129  encoder.AppendData(kIdentifierNameToDIE);
130  encoder.AppendU32(m_map.GetSize());
131  for (const auto &entry : m_map) {
132    // Make sure there are no empty strings.
133    assert((bool)entry.cstring);
134    encoder.AppendU32(strtab.Add(entry.cstring));
135    entry.value.Encode(encoder);
136  }
137}
138
139bool NameToDIE::operator==(const NameToDIE &rhs) const {
140  const size_t size = m_map.GetSize();
141  if (size != rhs.m_map.GetSize())
142    return false;
143  for (size_t i = 0; i < size; ++i) {
144    if (m_map.GetCStringAtIndex(i) != rhs.m_map.GetCStringAtIndex(i))
145      return false;
146    if (m_map.GetValueRefAtIndexUnchecked(i) !=
147        rhs.m_map.GetValueRefAtIndexUnchecked(i))
148      return false;
149  }
150  return true;
151}
152