1 //===-- llvm/CodeGen/DwarfFile.h - Dwarf Debug Framework -------*- C++ -*--===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_DWARFFILE_H
11 #define LLVM_LIB_CODEGEN_ASMPRINTER_DWARFFILE_H
12 
13 #include "AddressPool.h"
14 #include "DwarfStringPool.h"
15 #include "llvm/ADT/DenseMap.h"
16 #include "llvm/ADT/FoldingSet.h"
17 #include "llvm/ADT/SmallVector.h"
18 #include "llvm/ADT/StringMap.h"
19 #include "llvm/CodeGen/DIE.h"
20 #include "llvm/IR/Metadata.h"
21 #include "llvm/Support/Allocator.h"
22 #include <memory>
23 
24 namespace llvm {
25 class AsmPrinter;
26 class DbgVariable;
27 class DwarfCompileUnit;
28 class DwarfUnit;
29 class DIEAbbrev;
30 class MCSymbol;
31 class DIE;
32 class LexicalScope;
33 class StringRef;
34 class DwarfDebug;
35 class MCSection;
36 class MDNode;
37 class DwarfFile {
38   // Target of Dwarf emission, used for sizing of abbreviations.
39   AsmPrinter *Asm;
40 
41   BumpPtrAllocator AbbrevAllocator;
42 
43   // Used to uniquely define abbreviations.
44   DIEAbbrevSet Abbrevs;
45 
46   // A pointer to all units in the section.
47   SmallVector<std::unique_ptr<DwarfCompileUnit>, 1> CUs;
48 
49   DwarfStringPool StrPool;
50 
51   // Collection of dbg variables of a scope.
52   DenseMap<LexicalScope *, SmallVector<DbgVariable *, 8>> ScopeVariables;
53 
54   // Collection of abstract subprogram DIEs.
55   DenseMap<const MDNode *, DIE *> AbstractSPDies;
56   DenseMap<const MDNode *, std::unique_ptr<DbgVariable>> AbstractVariables;
57 
58   /// Maps MDNodes for type system with the corresponding DIEs. These DIEs can
59   /// be shared across CUs, that is why we keep the map here instead
60   /// of in DwarfCompileUnit.
61   DenseMap<const MDNode *, DIE *> DITypeNodeToDieMap;
62 
63 public:
64   DwarfFile(AsmPrinter *AP, StringRef Pref, BumpPtrAllocator &DA);
65 
66   const SmallVectorImpl<std::unique_ptr<DwarfCompileUnit>> &getUnits() {
67     return CUs;
68   }
69 
70   /// \brief Compute the size and offset of a DIE given an incoming Offset.
71   unsigned computeSizeAndOffset(DIE &Die, unsigned Offset);
72 
73   /// \brief Compute the size and offset of all the DIEs.
74   void computeSizeAndOffsets();
75 
76   /// \brief Compute the size and offset of all the DIEs in the given unit.
77   /// \returns The size of the root DIE.
78   unsigned computeSizeAndOffsetsForUnit(DwarfUnit *TheU);
79 
80   /// \brief Add a unit to the list of CUs.
81   void addUnit(std::unique_ptr<DwarfCompileUnit> U);
82 
83   /// \brief Emit all of the units to the section listed with the given
84   /// abbreviation section.
85   void emitUnits(bool UseOffsets);
86 
87   /// \brief Emit the given unit to its section.
88   void emitUnit(DwarfUnit *U, bool UseOffsets);
89 
90   /// \brief Emit a set of abbreviations to the specific section.
91   void emitAbbrevs(MCSection *);
92 
93   /// \brief Emit all of the strings to the section given.
94   void emitStrings(MCSection *StrSection, MCSection *OffsetSection = nullptr);
95 
96   /// \brief Returns the string pool.
97   DwarfStringPool &getStringPool() { return StrPool; }
98 
99   /// \returns false if the variable was merged with a previous one.
100   bool addScopeVariable(LexicalScope *LS, DbgVariable *Var);
101 
102   DenseMap<LexicalScope *, SmallVector<DbgVariable *, 8>> &getScopeVariables() {
103     return ScopeVariables;
104   }
105 
106   DenseMap<const MDNode *, DIE *> &getAbstractSPDies() {
107     return AbstractSPDies;
108   }
109   DenseMap<const MDNode *, std::unique_ptr<DbgVariable>> &getAbstractVariables() {
110     return AbstractVariables;
111   }
112 
113   void insertDIE(const MDNode *TypeMD, DIE *Die) {
114     DITypeNodeToDieMap.insert(std::make_pair(TypeMD, Die));
115   }
116   DIE *getDIE(const MDNode *TypeMD) {
117     return DITypeNodeToDieMap.lookup(TypeMD);
118   }
119 };
120 }
121 #endif
122