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/IR/Metadata.h"
20 #include "llvm/Support/Allocator.h"
21 #include <memory>
22 #include <string>
23 #include <vector>
24 
25 namespace llvm {
26 class AsmPrinter;
27 class DbgVariable;
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   FoldingSet<DIEAbbrev> AbbreviationsSet;
45 
46   // A list of all the unique abbreviations in use.
47   std::vector<DIEAbbrev *> Abbreviations;
48 
49   // A pointer to all units in the section.
50   SmallVector<std::unique_ptr<DwarfUnit>, 1> CUs;
51 
52   DwarfStringPool StrPool;
53 
54   // Collection of dbg variables of a scope.
55   DenseMap<LexicalScope *, SmallVector<DbgVariable *, 8>> ScopeVariables;
56 
57   // Collection of abstract subprogram DIEs.
58   DenseMap<const MDNode *, DIE *> AbstractSPDies;
59 
60   /// Maps MDNodes for type system with the corresponding DIEs. These DIEs can
61   /// be shared across CUs, that is why we keep the map here instead
62   /// of in DwarfCompileUnit.
63   DenseMap<const MDNode *, DIE *> DITypeNodeToDieMap;
64 
65 public:
66   DwarfFile(AsmPrinter *AP, StringRef Pref, BumpPtrAllocator &DA);
67 
68   ~DwarfFile();
69 
70   const SmallVectorImpl<std::unique_ptr<DwarfUnit>> &getUnits() { return CUs; }
71 
72   /// \brief Compute the size and offset of a DIE given an incoming Offset.
73   unsigned computeSizeAndOffset(DIE &Die, unsigned Offset);
74 
75   /// \brief Compute the size and offset of all the DIEs.
76   void computeSizeAndOffsets();
77 
78   /// Define a unique number for the abbreviation.
79   ///
80   /// Compute the abbreviation for \c Die, look up its unique number, and
81   /// return a reference to it in the uniquing table.
82   DIEAbbrev &assignAbbrevNumber(DIE &Die);
83 
84   /// \brief Add a unit to the list of CUs.
85   void addUnit(std::unique_ptr<DwarfUnit> U);
86 
87   /// \brief Emit all of the units to the section listed with the given
88   /// abbreviation section.
89   void emitUnits(bool UseOffsets);
90 
91   /// \brief Emit a set of abbreviations to the specific section.
92   void emitAbbrevs(MCSection *);
93 
94   /// \brief Emit all of the strings to the section given.
95   void emitStrings(MCSection *StrSection, MCSection *OffsetSection = nullptr);
96 
97   /// \brief Returns the string pool.
98   DwarfStringPool &getStringPool() { return StrPool; }
99 
100   /// \returns false if the variable was merged with a previous one.
101   bool addScopeVariable(LexicalScope *LS, DbgVariable *Var);
102 
103   DenseMap<LexicalScope *, SmallVector<DbgVariable *, 8>> &getScopeVariables() {
104     return ScopeVariables;
105   }
106 
107   DenseMap<const MDNode *, DIE *> &getAbstractSPDies() {
108     return AbstractSPDies;
109   }
110 
111   void insertDIE(const MDNode *TypeMD, DIE *Die) {
112     DITypeNodeToDieMap.insert(std::make_pair(TypeMD, Die));
113   }
114   DIE *getDIE(const MDNode *TypeMD) {
115     return DITypeNodeToDieMap.lookup(TypeMD);
116   }
117 };
118 }
119 #endif
120