1//===- llvm/CodeGen/DwarfFile.h - Dwarf Debug Framework ---------*- 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_CODEGEN_ASMPRINTER_DWARFFILE_H
10#define LLVM_LIB_CODEGEN_ASMPRINTER_DWARFFILE_H
11
12#include "DwarfStringPool.h"
13#include "llvm/ADT/DenseMap.h"
14#include "llvm/ADT/SmallVector.h"
15#include "llvm/ADT/StringRef.h"
16#include "llvm/CodeGen/DIE.h"
17#include "llvm/Support/Allocator.h"
18#include <map>
19#include <memory>
20#include <utility>
21
22namespace llvm {
23
24class AsmPrinter;
25class DbgEntity;
26class DbgVariable;
27class DbgLabel;
28class DINode;
29class DILocalScope;
30class DwarfCompileUnit;
31class DwarfUnit;
32class LexicalScope;
33class MCSection;
34class MDNode;
35
36// Data structure to hold a range for range lists.
37struct RangeSpan {
38 const MCSymbol *Begin;
39 const MCSymbol *End;
40};
41
42struct RangeSpanList {
43 // Index for locating within the debug_range section this particular span.
44 MCSymbol *Label;
45 const DwarfCompileUnit *CU;
46 // List of ranges.
47 SmallVector<RangeSpan, 2> Ranges;
48};
49
50class DwarfFile {
51 // Target of Dwarf emission, used for sizing of abbreviations.
52 AsmPrinter *Asm;
53
54 BumpPtrAllocator AbbrevAllocator;
55
56 // Used to uniquely define abbreviations.
57 DIEAbbrevSet Abbrevs;
58
59 // A pointer to all units in the section.
60 SmallVector<std::unique_ptr<DwarfCompileUnit>, 1> CUs;
61
62 DwarfStringPool StrPool;
63
64 // List of range lists for a given compile unit, separate from the ranges for
65 // the CU itself.
66 SmallVector<RangeSpanList, 1> CURangeLists;
67
68 /// DWARF v5: The symbol that designates the start of the contribution to
69 /// the string offsets table. The contribution is shared by all units.
70 MCSymbol *StringOffsetsStartSym = nullptr;
71
72 /// DWARF v5: The symbol that designates the base of the range list table.
73 /// The table is shared by all units.
74 MCSymbol *RnglistsTableBaseSym = nullptr;
75
76 /// The variables of a lexical scope.
77 struct ScopeVars {
78 /// We need to sort Args by ArgNo and check for duplicates. This could also
79 /// be implemented as a list or vector + std::lower_bound().
80 std::map<unsigned, DbgVariable *> Args;
81 SmallVector<DbgVariable *, 8> Locals;
82 };
83 /// Collection of DbgVariables of each lexical scope.
84 DenseMap<LexicalScope *, ScopeVars> ScopeVariables;
85
86 /// Collection of DbgLabels of each lexical scope.
87 using LabelList = SmallVector<DbgLabel *, 4>;
88 DenseMap<LexicalScope *, LabelList> ScopeLabels;
89
90 // Collection of abstract subprogram DIEs.
91 DenseMap<const DILocalScope *, DIE *> AbstractLocalScopeDIEs;
92 DenseMap<const DINode *, std::unique_ptr<DbgEntity>> AbstractEntities;
93
94 /// Maps MDNodes for type system with the corresponding DIEs. These DIEs can
95 /// be shared across CUs, that is why we keep the map here instead
96 /// of in DwarfCompileUnit.
97 DenseMap<const MDNode *, DIE *> DITypeNodeToDieMap;
98
99public:
100 DwarfFile(AsmPrinter *AP, StringRef Pref, BumpPtrAllocator &DA);
101
102 const SmallVectorImpl<std::unique_ptr<DwarfCompileUnit>> &getUnits() {
103 return CUs;
104 }
105
106 std::pair<uint32_t, RangeSpanList *> addRange(const DwarfCompileUnit &CU,
107 SmallVector<RangeSpan, 2> R);
108
109 /// getRangeLists - Get the vector of range lists.
110 const SmallVectorImpl<RangeSpanList> &getRangeLists() const {
111 return CURangeLists;
112 }
113
114 /// Compute the size and offset of a DIE given an incoming Offset.
115 unsigned computeSizeAndOffset(DIE &Die, unsigned Offset);
116
117 /// Compute the size and offset of all the DIEs.
118 void computeSizeAndOffsets();
119
120 /// Compute the size and offset of all the DIEs in the given unit.
121 /// \returns The size of the root DIE.
122 unsigned computeSizeAndOffsetsForUnit(DwarfUnit *TheU);
123
124 /// Add a unit to the list of CUs.
125 void addUnit(std::unique_ptr<DwarfCompileUnit> U);
126
127 /// Emit all of the units to the section listed with the given
128 /// abbreviation section.
129 void emitUnits(bool UseOffsets);
130
131 /// Emit the given unit to its section.
132 void emitUnit(DwarfUnit *TheU, bool UseOffsets);
133
134 /// Emit a set of abbreviations to the specific section.
135 void emitAbbrevs(MCSection *);
136
137 /// Emit all of the strings to the section given. If OffsetSection is
138 /// non-null, emit a table of string offsets to it. If UseRelativeOffsets
139 /// is false, emit absolute offsets to the strings. Otherwise, emit
140 /// relocatable references to the strings if they are supported by the target.
141 void emitStrings(MCSection *StrSection, MCSection *OffsetSection = nullptr,
142 bool UseRelativeOffsets = false);
143
144 /// Returns the string pool.
145 DwarfStringPool &getStringPool() { return StrPool; }
146
147 MCSymbol *getStringOffsetsStartSym() const { return StringOffsetsStartSym; }
148 void setStringOffsetsStartSym(MCSymbol *Sym) { StringOffsetsStartSym = Sym; }
149
150 MCSymbol *getRnglistsTableBaseSym() const { return RnglistsTableBaseSym; }
151 void setRnglistsTableBaseSym(MCSymbol *Sym) { RnglistsTableBaseSym = Sym; }
152
153 void addScopeVariable(LexicalScope *LS, DbgVariable *Var);
154
155 void addScopeLabel(LexicalScope *LS, DbgLabel *Label);
156
157 DenseMap<LexicalScope *, ScopeVars> &getScopeVariables() {
158 return ScopeVariables;
159 }
160
161 DenseMap<LexicalScope *, LabelList> &getScopeLabels() {
162 return ScopeLabels;
163 }
164
165 DenseMap<const DILocalScope *, DIE *> &getAbstractScopeDIEs() {
166 return AbstractLocalScopeDIEs;
167 }
168
169 DenseMap<const DINode *, std::unique_ptr<DbgEntity>> &getAbstractEntities() {
170 return AbstractEntities;
171 }
172
173 void insertDIE(const MDNode *TypeMD, DIE *Die) {
174 DITypeNodeToDieMap.insert(KV: std::make_pair(x&: TypeMD, y&: Die));
175 }
176
177 DIE *getDIE(const MDNode *TypeMD) {
178 return DITypeNodeToDieMap.lookup(Val: TypeMD);
179 }
180};
181
182} // end namespace llvm
183
184#endif // LLVM_LIB_CODEGEN_ASMPRINTER_DWARFFILE_H
185