1 //===-- SymbolFileDWARFDwo.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 "SymbolFileDWARFDwo.h"
10 
11 #include "lldb/Core/Section.h"
12 #include "lldb/Expression/DWARFExpression.h"
13 #include "lldb/Symbol/ObjectFile.h"
14 #include "lldb/Utility/LLDBAssert.h"
15 #include "llvm/Support/Casting.h"
16 
17 #include "DWARFCompileUnit.h"
18 #include "DWARFDebugInfo.h"
19 #include "DWARFUnit.h"
20 #include <optional>
21 
22 using namespace lldb;
23 using namespace lldb_private;
24 
25 char SymbolFileDWARFDwo::ID;
26 
27 SymbolFileDWARFDwo::SymbolFileDWARFDwo(SymbolFileDWARF &base_symbol_file,
28                                        ObjectFileSP objfile, uint32_t id)
29     : SymbolFileDWARF(objfile, objfile->GetSectionList(
30                                    /*update_module_section_list*/ false)),
31       m_base_symbol_file(base_symbol_file) {
32   SetID(user_id_t(id) << 32);
33 
34   // Parsing of the dwarf unit index is not thread-safe, so we need to prime it
35   // to enable subsequent concurrent lookups.
36   m_context.GetAsLLVM().getCUIndex();
37 }
38 
39 DWARFCompileUnit *SymbolFileDWARFDwo::GetDWOCompileUnitForHash(uint64_t hash) {
40   if (const llvm::DWARFUnitIndex &index = m_context.GetAsLLVM().getCUIndex()) {
41     if (const llvm::DWARFUnitIndex::Entry *entry = index.getFromHash(hash)) {
42       if (auto *unit_contrib = entry->getContribution())
43         return llvm::dyn_cast_or_null<DWARFCompileUnit>(
44             DebugInfo().GetUnitAtOffset(DIERef::Section::DebugInfo,
45                                         unit_contrib->getOffset32()));
46     }
47     return nullptr;
48   }
49 
50   DWARFCompileUnit *cu = FindSingleCompileUnit();
51   if (!cu)
52     return nullptr;
53   std::optional<uint64_t> dwo_id = cu->GetDWOId();
54   if (!dwo_id || hash != *dwo_id)
55     return nullptr;
56   return cu;
57 }
58 
59 DWARFCompileUnit *SymbolFileDWARFDwo::FindSingleCompileUnit() {
60   DWARFDebugInfo &debug_info = DebugInfo();
61 
62   // Right now we only support dwo files with one compile unit. If we don't have
63   // type units, we can just check for the unit count.
64   if (!debug_info.ContainsTypeUnits() && debug_info.GetNumUnits() == 1)
65     return llvm::cast<DWARFCompileUnit>(debug_info.GetUnitAtIndex(0));
66 
67   // Otherwise, we have to run through all units, and find the compile unit that
68   // way.
69   DWARFCompileUnit *cu = nullptr;
70   for (size_t i = 0; i < debug_info.GetNumUnits(); ++i) {
71     if (auto *candidate =
72             llvm::dyn_cast<DWARFCompileUnit>(debug_info.GetUnitAtIndex(i))) {
73       if (cu)
74         return nullptr; // More that one CU found.
75       cu = candidate;
76     }
77   }
78   return cu;
79 }
80 
81 lldb::offset_t SymbolFileDWARFDwo::GetVendorDWARFOpcodeSize(
82     const lldb_private::DataExtractor &data, const lldb::offset_t data_offset,
83     const uint8_t op) const {
84   return GetBaseSymbolFile().GetVendorDWARFOpcodeSize(data, data_offset, op);
85 }
86 
87 bool SymbolFileDWARFDwo::ParseVendorDWARFOpcode(
88     uint8_t op, const lldb_private::DataExtractor &opcodes,
89     lldb::offset_t &offset, std::vector<lldb_private::Value> &stack) const {
90   return GetBaseSymbolFile().ParseVendorDWARFOpcode(op, opcodes, offset, stack);
91 }
92 
93 SymbolFileDWARF::DIEToTypePtr &SymbolFileDWARFDwo::GetDIEToType() {
94   return GetBaseSymbolFile().GetDIEToType();
95 }
96 
97 SymbolFileDWARF::DIEToVariableSP &SymbolFileDWARFDwo::GetDIEToVariable() {
98   return GetBaseSymbolFile().GetDIEToVariable();
99 }
100 
101 SymbolFileDWARF::DIEToClangType &
102 SymbolFileDWARFDwo::GetForwardDeclDieToClangType() {
103   return GetBaseSymbolFile().GetForwardDeclDieToClangType();
104 }
105 
106 SymbolFileDWARF::ClangTypeToDIE &
107 SymbolFileDWARFDwo::GetForwardDeclClangTypeToDie() {
108   return GetBaseSymbolFile().GetForwardDeclClangTypeToDie();
109 }
110 
111 void SymbolFileDWARFDwo::GetObjCMethods(
112     lldb_private::ConstString class_name,
113     llvm::function_ref<bool(DWARFDIE die)> callback) {
114   GetBaseSymbolFile().GetObjCMethods(class_name, callback);
115 }
116 
117 UniqueDWARFASTTypeMap &SymbolFileDWARFDwo::GetUniqueDWARFASTTypeMap() {
118   return GetBaseSymbolFile().GetUniqueDWARFASTTypeMap();
119 }
120 
121 lldb::TypeSP
122 SymbolFileDWARFDwo::FindDefinitionTypeForDWARFDeclContext(const DWARFDIE &die) {
123   return GetBaseSymbolFile().FindDefinitionTypeForDWARFDeclContext(die);
124 }
125 
126 lldb::TypeSP SymbolFileDWARFDwo::FindCompleteObjCDefinitionTypeForDIE(
127     const DWARFDIE &die, lldb_private::ConstString type_name,
128     bool must_be_implementation) {
129   return GetBaseSymbolFile().FindCompleteObjCDefinitionTypeForDIE(
130       die, type_name, must_be_implementation);
131 }
132 
133 llvm::Expected<lldb::TypeSystemSP>
134 SymbolFileDWARFDwo::GetTypeSystemForLanguage(LanguageType language) {
135   return GetBaseSymbolFile().GetTypeSystemForLanguage(language);
136 }
137 
138 DWARFDIE
139 SymbolFileDWARFDwo::GetDIE(const DIERef &die_ref) {
140   if (die_ref.dwo_num() == GetDwoNum())
141     return DebugInfo().GetDIE(die_ref);
142   return GetBaseSymbolFile().GetDIE(die_ref);
143 }
144