lldb/source/Plugins/SymbolFile/DWARF/NameToDIE.cpp

   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
  21 using namespace lldb;
  22 using namespace lldb_private;
  23 using namespace lldb_private::plugin::dwarf;
  24
  25 void NameToDIE::Finalize() {
  26   m_map.Sort(std::less<DIERef>());
  27   m_map.SizeToFit();
  28 }
  29
  30 void NameToDIE::Insert(ConstString name, const DIERef &die_ref) {
  31   m_map.Append(name, die_ref);
  32 }
  33
  34 bool NameToDIE::Find(ConstString name,
  35                      llvm::function_ref<bool(DIERef ref)> callback) const {
  36   for (const auto &entry : m_map.equal_range(name))
  37     if (!callback(entry.value))
  38       return false;
  39   return true;
  40 }
  41
  42 bool NameToDIE::Find(const RegularExpression &regex,
  43                      llvm::function_ref<bool(DIERef ref)> callback) const {
  44   for (const auto &entry : m_map)
  45     if (regex.Execute(entry.cstring.GetCString())) {
  46       if (!callback(entry.value))
  47         return false;
  48     }
  49   return true;
  50 }
  51
  52 void NameToDIE::FindAllEntriesForUnit(
  53     DWARFUnit &s_unit, llvm::function_ref<bool(DIERef ref)> callback) const {
  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().GetFileIndex() == die_ref.file_index() &&
  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
  68 void 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
  76 void 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
  87 void 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
  95 constexpr llvm::StringLiteral kIdentifierNameToDIE("N2DI");
  96
  97 bool 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
 128 void 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
 139 bool 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 }