1 //===-- DWARFUnit.h ---------------------------------------------*- 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 SymbolFileDWARF_DWARFUnit_h_
11 #define SymbolFileDWARF_DWARFUnit_h_
12 
13 #include "DWARFDIE.h"
14 #include "DWARFDebugInfoEntry.h"
15 #include "lldb/lldb-enumerations.h"
16 #include "llvm/Support/RWMutex.h"
17 #include <atomic>
18 
19 class DWARFUnit;
20 class DWARFCompileUnit;
21 class NameToDIE;
22 class SymbolFileDWARF;
23 class SymbolFileDWARFDwo;
24 
25 typedef std::shared_ptr<DWARFUnit> DWARFUnitSP;
26 
27 enum DWARFProducer {
28   eProducerInvalid = 0,
29   eProducerClang,
30   eProducerGCC,
31   eProducerLLVMGCC,
32   eProcucerOther
33 };
34 
35 class DWARFUnit {
36   using die_iterator_range =
37       llvm::iterator_range<DWARFDebugInfoEntry::collection::iterator>;
38 
39 public:
40   virtual ~DWARFUnit();
41 
42   void ExtractUnitDIEIfNeeded();
43   void ExtractDIEsIfNeeded();
44 
45   class ScopedExtractDIEs {
46     DWARFUnit *m_cu;
47   public:
48     bool m_clear_dies = false;
49     ScopedExtractDIEs(DWARFUnit *cu);
50     ~ScopedExtractDIEs();
51     DISALLOW_COPY_AND_ASSIGN(ScopedExtractDIEs);
52     ScopedExtractDIEs(ScopedExtractDIEs &&rhs);
53     ScopedExtractDIEs &operator=(ScopedExtractDIEs &&rhs);
54   };
55   ScopedExtractDIEs ExtractDIEsScoped();
56 
57   DWARFDIE LookupAddress(const dw_addr_t address);
58   size_t AppendDIEsWithTag(const dw_tag_t tag,
59                            DWARFDIECollection &matching_dies,
60                            uint32_t depth = UINT32_MAX) const;
61   bool Verify(lldb_private::Stream *s) const;
62   virtual void Dump(lldb_private::Stream *s) const = 0;
63   //------------------------------------------------------------------
64   /// Get the data that contains the DIE information for this unit.
65   ///
66   /// This will return the correct bytes that contain the data for
67   /// this DWARFUnit. It could be .debug_info or .debug_types
68   /// depending on where the data for this unit originates.
69   ///
70   /// @return
71   ///   The correct data for the DIE information in this unit.
72   //------------------------------------------------------------------
73   virtual const lldb_private::DWARFDataExtractor &GetData() const = 0;
74   //------------------------------------------------------------------
75   /// Get the size in bytes of the compile unit header.
76   ///
77   /// @return
78   ///     Byte size of the compile unit header
79   //------------------------------------------------------------------
80   virtual uint32_t GetHeaderByteSize() const = 0;
81   // Offset of the initial length field.
82   dw_offset_t GetOffset() const { return m_offset; }
83   lldb::user_id_t GetID() const;
84   //------------------------------------------------------------------
85   /// Get the size in bytes of the length field in the header.
86   ///
87   /// In DWARF32 this is just 4 bytes, and DWARF64 it is 12 where 4
88   /// are 0xFFFFFFFF followed by the actual 64 bit length.
89   ///
90   /// @return
91   ///     Byte size of the compile unit header length field
92   //------------------------------------------------------------------
93   size_t GetLengthByteSize() const { return IsDWARF64() ? 12 : 4; }
94 
95   bool ContainsDIEOffset(dw_offset_t die_offset) const {
96     return die_offset >= GetFirstDIEOffset() &&
97            die_offset < GetNextCompileUnitOffset();
98   }
99   dw_offset_t GetFirstDIEOffset() const {
100     return m_offset + GetHeaderByteSize();
101   }
102   dw_offset_t GetNextCompileUnitOffset() const;
103   // Size of the CU data (without initial length and without header).
104   size_t GetDebugInfoSize() const;
105   // Size of the CU data incl. header but without initial length.
106   uint32_t GetLength() const { return m_length; }
107   uint16_t GetVersion() const { return m_version; }
108   const DWARFAbbreviationDeclarationSet *GetAbbreviations() const;
109   dw_offset_t GetAbbrevOffset() const;
110   uint8_t GetAddressByteSize() const { return m_addr_size; }
111   dw_addr_t GetBaseAddress() const { return m_base_addr; }
112   dw_addr_t GetAddrBase() const { return m_addr_base; }
113   dw_addr_t GetRangesBase() const { return m_ranges_base; }
114   void SetAddrBase(dw_addr_t addr_base, dw_addr_t ranges_base,
115                    dw_offset_t base_obj_offset);
116   void BuildAddressRangeTable(SymbolFileDWARF *dwarf,
117                               DWARFDebugAranges *debug_aranges);
118 
119   lldb::ByteOrder GetByteOrder() const;
120 
121   lldb_private::TypeSystem *GetTypeSystem();
122 
123   const DWARFDebugAranges &GetFunctionAranges();
124 
125   DWARFFormValue::FixedFormSizes GetFixedFormSizes();
126 
127   void SetBaseAddress(dw_addr_t base_addr);
128 
129   DWARFBaseDIE GetUnitDIEOnly() { return DWARFDIE(this, GetUnitDIEPtrOnly()); }
130 
131   DWARFDIE DIE() { return DWARFDIE(this, DIEPtr()); }
132 
133   DWARFDIE GetDIE(dw_offset_t die_offset);
134 
135   static uint8_t GetAddressByteSize(const DWARFUnit *cu);
136 
137   static bool IsDWARF64(const DWARFUnit *cu);
138 
139   static uint8_t GetDefaultAddressSize();
140 
141   void *GetUserData() const;
142 
143   void SetUserData(void *d);
144 
145   bool Supports_DW_AT_APPLE_objc_complete_type();
146 
147   bool DW_AT_decl_file_attributes_are_invalid();
148 
149   bool Supports_unnamed_objc_bitfields();
150 
151   SymbolFileDWARF *GetSymbolFileDWARF() const;
152 
153   DWARFProducer GetProducer();
154 
155   uint32_t GetProducerVersionMajor();
156 
157   uint32_t GetProducerVersionMinor();
158 
159   uint32_t GetProducerVersionUpdate();
160 
161   static lldb::LanguageType LanguageTypeFromDWARF(uint64_t val);
162 
163   lldb::LanguageType GetLanguageType();
164 
165   bool IsDWARF64() const { return m_is_dwarf64; }
166 
167   bool GetIsOptimized();
168 
169   SymbolFileDWARFDwo *GetDwoSymbolFile() const;
170 
171   dw_offset_t GetBaseObjOffset() const;
172 
173   die_iterator_range dies() {
174     ExtractDIEsIfNeeded();
175     return die_iterator_range(m_die_array.begin(), m_die_array.end());
176   }
177 
178 protected:
179   DWARFUnit(SymbolFileDWARF *dwarf);
180 
181   SymbolFileDWARF *m_dwarf = nullptr;
182   std::unique_ptr<SymbolFileDWARFDwo> m_dwo_symbol_file;
183   const DWARFAbbreviationDeclarationSet *m_abbrevs = nullptr;
184   void *m_user_data = nullptr;
185   // The compile unit debug information entry item
186   DWARFDebugInfoEntry::collection m_die_array;
187   mutable llvm::sys::RWMutex m_die_array_mutex;
188   // It is used for tracking of ScopedExtractDIEs instances.
189   mutable llvm::sys::RWMutex m_die_array_scoped_mutex;
190   // ScopedExtractDIEs instances should not call ClearDIEsRWLocked()
191   // as someone called ExtractDIEsIfNeeded().
192   std::atomic<bool> m_cancel_scopes;
193   // GetUnitDIEPtrOnly() needs to return pointer to the first DIE.
194   // But the first element of m_die_array after ExtractUnitDIEIfNeeded()
195   // would possibly move in memory after later ExtractDIEsIfNeeded().
196   DWARFDebugInfoEntry m_first_die;
197   llvm::sys::RWMutex m_first_die_mutex;
198   // A table similar to the .debug_aranges table, but this one points to the
199   // exact DW_TAG_subprogram DIEs
200   std::unique_ptr<DWARFDebugAranges> m_func_aranges_ap;
201   dw_addr_t m_base_addr = 0;
202   dw_offset_t m_length = 0;
203   uint16_t m_version = 0;
204   uint8_t m_addr_size = 0;
205   uint8_t m_unit_type = 0;
206   uint64_t m_dwo_id = 0;
207   DWARFProducer m_producer = eProducerInvalid;
208   uint32_t m_producer_version_major = 0;
209   uint32_t m_producer_version_minor = 0;
210   uint32_t m_producer_version_update = 0;
211   lldb::LanguageType m_language_type = lldb::eLanguageTypeUnknown;
212   bool m_is_dwarf64 = false;
213   lldb_private::LazyBool m_is_optimized = lldb_private::eLazyBoolCalculate;
214   dw_addr_t m_addr_base = 0;   // Value of DW_AT_addr_base
215   dw_addr_t m_ranges_base = 0; // Value of DW_AT_ranges_base
216   // If this is a dwo compile unit this is the offset of the base compile unit
217   // in the main object file
218   dw_offset_t m_base_obj_offset = DW_INVALID_OFFSET;
219 
220   // Offset of the initial length field.
221   dw_offset_t m_offset;
222 
223 private:
224   void ParseProducerInfo();
225   void ExtractDIEsRWLocked();
226   void ClearDIEsRWLocked();
227 
228   // Get the DWARF unit DWARF debug informration entry. Parse the single DIE
229   // if needed.
230   const DWARFDebugInfoEntry *GetUnitDIEPtrOnly() {
231     ExtractUnitDIEIfNeeded();
232     // m_first_die_mutex is not required as m_first_die is never cleared.
233     if (!m_first_die)
234       return NULL;
235     return &m_first_die;
236   }
237 
238   // Get all DWARF debug informration entries. Parse all DIEs if needed.
239   const DWARFDebugInfoEntry *DIEPtr() {
240     ExtractDIEsIfNeeded();
241     if (m_die_array.empty())
242       return NULL;
243     return &m_die_array[0];
244   }
245 
246   void AddUnitDIE(const DWARFDebugInfoEntry &cu_die);
247   void ExtractDIEsEndCheck(lldb::offset_t offset) const;
248 
249   DISALLOW_COPY_AND_ASSIGN(DWARFUnit);
250 };
251 
252 #endif // SymbolFileDWARF_DWARFUnit_h_
253