1//===- DWARFLinkerUnit.h ----------------------------------------*- 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#ifndef LLVM_LIB_DWARFLINKER_PARALLEL_DWARFLINKERUNIT_H
10#define LLVM_LIB_DWARFLINKER_PARALLEL_DWARFLINKERUNIT_H
11
12#include "DWARFLinkerGlobalData.h"
13#include "OutputSections.h"
14#include "llvm/CodeGen/DIE.h"
15#include "llvm/DWARFLinker/IndexedValuesMap.h"
16#include "llvm/DWARFLinker/Parallel/DWARFLinker.h"
17#include "llvm/DWARFLinker/StringPool.h"
18#include "llvm/DebugInfo/DWARF/DWARFUnit.h"
19#include "llvm/Support/LEB128.h"
20
21namespace llvm {
22namespace dwarf_linker {
23namespace parallel {
24
25class DwarfUnit;
26using MacroOffset2UnitMapTy = DenseMap<uint64_t, DwarfUnit *>;
27
28/// Base class for all Dwarf units(Compile unit/Type table unit).
29class DwarfUnit : public OutputSections {
30public:
31 virtual ~DwarfUnit() {}
32 DwarfUnit(LinkingGlobalData &GlobalData, unsigned ID,
33 StringRef ClangModuleName)
34 : OutputSections(GlobalData), ID(ID), ClangModuleName(ClangModuleName),
35 OutUnitDIE(nullptr) {}
36
37 /// Unique id of the unit.
38 unsigned getUniqueID() const { return ID; }
39
40 /// Returns size of this(newly generated) compile unit.
41 uint64_t getUnitSize() const { return UnitSize; }
42
43 /// Returns this unit name.
44 StringRef getUnitName() const { return UnitName; }
45
46 /// Return the DW_AT_LLVM_sysroot of the compile unit or an empty StringRef.
47 StringRef getSysRoot() { return SysRoot; }
48
49 /// Return true if this compile unit is from Clang module.
50 bool isClangModule() const { return !ClangModuleName.empty(); }
51
52 /// Return Clang module name;
53 const std::string &getClangModuleName() const { return ClangModuleName; }
54
55 /// Return global data.
56 LinkingGlobalData &getGlobalData() { return GlobalData; }
57
58 /// Returns true if unit is inter-connected(it references/referenced by other
59 /// unit).
60 bool isInterconnectedCU() const { return IsInterconnectedCU; }
61
62 /// Mark this unit as inter-connected(it references/referenced by other unit).
63 void setInterconnectedCU() { IsInterconnectedCU = true; }
64
65 /// Adds \p Abbrev into unit`s abbreviation table.
66 void assignAbbrev(DIEAbbrev &Abbrev);
67
68 /// Returns abbreviations for this compile unit.
69 const std::vector<std::unique_ptr<DIEAbbrev>> &getAbbreviations() const {
70 return Abbreviations;
71 }
72
73 /// Returns output unit DIE.
74 DIE *getOutUnitDIE() { return OutUnitDIE; }
75
76 /// Set output unit DIE.
77 void setOutUnitDIE(DIE *UnitDie) {
78 OutUnitDIE = UnitDie;
79
80 if (OutUnitDIE != nullptr)
81 UnitSize = getDebugInfoHeaderSize() + OutUnitDIE->getSize();
82 }
83
84 /// \defgroup Methods used to emit unit's debug info:
85 ///
86 /// @{
87 /// Emit unit's abbreviations.
88 Error emitAbbreviations();
89
90 /// Emit .debug_info section for unit DIEs.
91 Error emitDebugInfo(const Triple &TargetTriple);
92
93 /// Emit .debug_line section.
94 Error emitDebugLine(const Triple &TargetTriple,
95 const DWARFDebugLine::LineTable &OutLineTable);
96
97 /// Emit the .debug_str_offsets section for current unit.
98 Error emitDebugStringOffsetSection();
99 /// @}
100
101 /// \defgroup Methods used for reporting warnings and errors:
102 ///
103 /// @{
104 void warn(const Twine &Warning) { GlobalData.warn(Warning, Context: getUnitName()); }
105
106 void error(const Twine &Err) { GlobalData.warn(Warning: Err, Context: getUnitName()); }
107 /// @}
108
109 /// \defgroup Methods and data members used for building accelerator tables:
110 ///
111 /// @{
112
113 enum class AccelType : uint8_t { None, Name, Namespace, ObjC, Type };
114
115 /// This structure keeps fields which would be used for creating accelerator
116 /// table.
117 struct AccelInfo {
118 AccelInfo() {
119 AvoidForPubSections = false;
120 ObjcClassImplementation = false;
121 }
122
123 /// Name of the entry.
124 StringEntry *String = nullptr;
125
126 /// Output offset of the DIE this entry describes.
127 uint64_t OutOffset;
128
129 /// Hash of the fully qualified name.
130 uint32_t QualifiedNameHash = 0;
131
132 /// Tag of the DIE this entry describes.
133 dwarf::Tag Tag = dwarf::DW_TAG_null;
134
135 /// Type of this accelerator record.
136 AccelType Type = AccelType::None;
137
138 /// Avoid emitting this entry for pub sections.
139 bool AvoidForPubSections : 1;
140
141 /// Is this an ObjC class implementation?
142 bool ObjcClassImplementation : 1;
143 };
144
145 /// Emit .debug_pubnames and .debug_pubtypes for \p Unit.
146 void emitPubAccelerators();
147
148 /// Enumerates accelerator data.
149 virtual void
150 forEachAcceleratorRecord(function_ref<void(AccelInfo &)> Handler) = 0;
151
152 /// @}
153
154 /// Returns index(inside .debug_str_offsets) of specified string.
155 virtual uint64_t getDebugStrIndex(const StringEntry *String) {
156 return DebugStringIndexMap.getValueIndex(Value: String);
157 }
158
159protected:
160 /// Emit single abbreviation entry.
161 void emitDwarfAbbrevEntry(const DIEAbbrev &Abbrev,
162 SectionDescriptor &AbbrevSection);
163
164 /// Emit single pubnames/pubtypes accelerator entry.
165 std::optional<uint64_t>
166 emitPubAcceleratorEntry(SectionDescriptor &OutSection, const AccelInfo &Info,
167 std::optional<uint64_t> LengthOffset);
168
169 /// Unique ID for the unit.
170 unsigned ID = 0;
171
172 /// The name of this unit.
173 std::string UnitName;
174
175 /// The DW_AT_LLVM_sysroot of this unit.
176 std::string SysRoot;
177
178 /// If this is a Clang module, this holds the module's name.
179 std::string ClangModuleName;
180
181 uint64_t UnitSize = 0;
182
183 /// true if current unit references_to/is_referenced by other unit.
184 std::atomic<bool> IsInterconnectedCU = {false};
185
186 /// FoldingSet that uniques the abbreviations.
187 FoldingSet<DIEAbbrev> AbbreviationsSet;
188
189 /// Storage for the unique Abbreviations.
190 std::vector<std::unique_ptr<DIEAbbrev>> Abbreviations;
191
192 /// Output unit DIE.
193 DIE *OutUnitDIE = nullptr;
194
195 /// Cache for file names for this unit.
196 using FileNamesCache =
197 DenseMap<uint64_t, std::pair<std::string, std::string>>;
198 FileNamesCache FileNames;
199
200 /// Maps a string into the index inside .debug_str_offsets section.
201 IndexedValuesMap<const StringEntry *> DebugStringIndexMap;
202};
203
204inline bool isODRLanguage(uint16_t Language) {
205 switch (Language) {
206 case dwarf::DW_LANG_C_plus_plus:
207 case dwarf::DW_LANG_C_plus_plus_03:
208 case dwarf::DW_LANG_C_plus_plus_11:
209 case dwarf::DW_LANG_C_plus_plus_14:
210 case dwarf::DW_LANG_ObjC_plus_plus:
211 return true;
212 default:
213 return false;
214 };
215
216 return false;
217}
218
219} // end of namespace parallel
220} // end of namespace dwarf_linker
221} // end of namespace llvm
222
223#endif // LLVM_LIB_DWARFLINKER_PARALLEL_DWARFLINKERUNIT_H
224

source code of llvm/lib/DWARFLinker/Parallel/DWARFLinkerUnit.h