1 files changed, 80 insertions, 1 deletions
diff --git a/contrib/llvm-project/lldb/include/lldb/Symbol/Symtab.h b/contrib/llvm-project/lldb/include/lldb/Symbol/Symtab.h
index e5d21c1bf4b3..fe0a82306c4f 100644
--- a/contrib/llvm-project/lldb/include/lldb/Symbol/Symtab.h
+++ b/contrib/llvm-project/lldb/include/lldb/Symbol/Symtab.h
@@ -131,7 +131,86 @@ public:
                               bool add_demangled, bool add_mangled,
                               NameToIndexMap &name_to_index_map) const;
 
-  ObjectFile *GetObjectFile() { return m_objfile; }
+  ObjectFile *GetObjectFile() const { return m_objfile; }
+
+  /// Decode a serialized version of this object from data.
+  ///
+  /// \param data
+  ///   The decoder object that references the serialized data.
+  ///
+  /// \param offset_ptr
+  ///   A pointer that contains the offset from which the data will be decoded
+  ///   from that gets updated as data gets decoded.
+  ///
+  /// \param[out] uuid_mismatch
+  ///   Set to true if a cache file exists but the UUID didn't match, false
+  ///   otherwise.
+  ///
+  /// \return
+  ///   True if the symbol table is successfully decoded and can be used,
+  ///   false otherwise.
+  bool Decode(const DataExtractor &data, lldb::offset_t *offset_ptr,
+              bool &uuid_mismatch);
+
+  /// Encode this object into a data encoder object.
+  ///
+  /// This allows this object to be serialized to disk. The object file must
+  /// have a valid Signature in order to be serialized as it is used to make
+  /// sure the cached information matches when cached data is loaded at a later
+  /// time. If the object file doesn't have a valid signature false will be
+  /// returned and it will indicate we should not cache this data.
+  ///
+  /// \param encoder
+  ///   A data encoder object that serialized bytes will be encoded into.
+  ///
+  /// \return
+  ///   True if the symbol table's object file can generate a valid signature
+  ///   and all data for the symbol table was encoded, false otherwise.
+  bool Encode(DataEncoder &encoder) const;
+
+  /// Get the cache key string for this symbol table.
+  ///
+  /// The cache key must start with the module's cache key and is followed
+  /// by information that indicates this key is for caching the symbol table
+  /// contents and should also include the has of the object file. A module can
+  /// be represented by an ObjectFile object for the main executable, but can
+  /// also have a symbol file that is from the same or a different object file.
+  /// This means we might have two symbol tables cached in the index cache, one
+  /// for the main executable and one for the symbol file.
+  ///
+  /// \return
+  ///   The unique cache key used to save and retrieve data from the index cache.
+  std::string GetCacheKey();
+
+  /// Save the symbol table data out into a cache.
+  ///
+  /// The symbol table will only be saved to a cache file if caching is enabled.
+  ///
+  /// We cache the contents of the symbol table since symbol tables in LLDB take
+  /// some time to initialize. This is due to the many sources for data that are
+  /// used to create a symbol table:
+  /// - standard symbol table
+  /// - dynamic symbol table (ELF)
+  /// - compressed debug info sections
+  /// - unwind information
+  /// - function pointers found in runtimes for global constructor/destructors
+  /// - other sources.
+  /// All of the above sources are combined and one symbol table results after
+  /// all sources have been considered.
+  void SaveToCache();
+
+  /// Load the symbol table from the index cache.
+  ///
+  /// Quickly load the finalized symbol table from the index cache. This saves
+  /// time when the debugger starts up. The index cache file for the symbol
+  /// table has the modification time set to the same time as the main module.
+  /// If the cache file exists and the modification times match, we will load
+  /// the symbol table from the serlized cache file.
+  ///
+  /// \return
+  ///   True if the symbol table was successfully loaded from the index cache,
+  ///   false if the symbol table wasn't cached or was out of date.
+  bool LoadFromCache();
 
 protected:
   typedef std::vector<Symbol> collection;