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