xref: /freebsd/contrib/llvm-project/lldb/include/lldb/Core/Mangled.h (revision 5f757f3ff9144b609b3c433dfd370cc6bdc191ad)
1 //===-- Mangled.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 LLDB_CORE_MANGLED_H
10 #define LLDB_CORE_MANGLED_H
11 
12 #include "lldb/lldb-enumerations.h"
13 #include "lldb/lldb-forward.h"
14 #include "lldb/lldb-types.h"
15 #include "lldb/Utility/ConstString.h"
16 #include "llvm/ADT/StringRef.h"
17 
18 #include <cstddef>
19 #include <memory>
20 
21 namespace lldb_private {
22 
23 /// \class Mangled Mangled.h "lldb/Core/Mangled.h"
24 /// A class that handles mangled names.
25 ///
26 /// Designed to handle mangled names. The demangled version of any names will
27 /// be computed when the demangled name is accessed through the Demangled()
28 /// accessor. This class can also tokenize the demangled version of the name
29 /// for powerful searches. Functions and symbols could make instances of this
30 /// class for their mangled names. Uniqued string pools are used for the
31 /// mangled, demangled, and token string values to allow for faster
32 /// comparisons and for efficient memory use.
33 class Mangled {
34 public:
35   enum NamePreference {
36     ePreferMangled,
37     ePreferDemangled,
38     ePreferDemangledWithoutArguments
39   };
40 
41   enum ManglingScheme {
42     eManglingSchemeNone = 0,
43     eManglingSchemeMSVC,
44     eManglingSchemeItanium,
45     eManglingSchemeRustV0,
46     eManglingSchemeD,
47     eManglingSchemeSwift,
48   };
49 
50   /// Default constructor.
51   ///
52   /// Initialize with both mangled and demangled names empty.
53   Mangled() = default;
54 
55   /// Construct with name.
56   ///
57   /// Constructor with an optional string and auto-detect if \a name is
58   /// mangled or not.
59   ///
60   /// \param[in] name
61   ///     The already const name to copy into this object.
62   explicit Mangled(ConstString name);
63 
64   explicit Mangled(llvm::StringRef name);
65 
66   bool operator==(const Mangled &rhs) const {
67     return m_mangled == rhs.m_mangled &&
68            GetDemangledName() == rhs.GetDemangledName();
69   }
70 
71   bool operator!=(const Mangled &rhs) const {
72     return !(*this == rhs);
73   }
74 
75   /// Convert to bool operator.
76   ///
77   /// This allows code to check any Mangled objects to see if they contain
78   /// anything valid using code such as:
79   ///
80   /// \code
81   /// Mangled mangled(...);
82   /// if (mangled)
83   /// { ...
84   /// \endcode
85   ///
86   /// \return
87   ///     Returns \b true if either the mangled or unmangled name is set,
88   ///     \b false if the object has an empty mangled and unmangled name.
89   explicit operator bool() const;
90 
91   /// Clear the mangled and demangled values.
92   void Clear();
93 
94   /// Compare the mangled string values
95   ///
96   /// Compares the Mangled::GetName() string in \a lhs and \a rhs.
97   ///
98   /// \param[in] lhs
99   ///     A const reference to the Left Hand Side object to compare.
100   ///
101   /// \param[in] rhs
102   ///     A const reference to the Right Hand Side object to compare.
103   ///
104   /// \return
105   ///     -1 if \a lhs is less than \a rhs
106   ///     0 if \a lhs is equal to \a rhs
107   ///     1 if \a lhs is greater than \a rhs
108   static int Compare(const Mangled &lhs, const Mangled &rhs);
109 
110   /// Dump a description of this object to a Stream \a s.
111   ///
112   /// Dump a Mangled object to stream \a s. We don't force our demangled name
113   /// to be computed currently (we don't use the accessor).
114   ///
115   /// \param[in] s
116   ///     The stream to which to dump the object description.
117   void Dump(Stream *s) const;
118 
119   /// Dump a debug description of this object to a Stream \a s.
120   ///
121   /// \param[in] s
122   ///     The stream to which to dump the object description.
123   void DumpDebug(Stream *s) const;
124 
125   /// Demangled name get accessor.
126   ///
127   /// \return
128   ///     A const reference to the demangled name string object.
129   ConstString GetDemangledName() const;
130 
131   /// Display demangled name get accessor.
132   ///
133   /// \return
134   ///     A const reference to the display demangled name string object.
135   ConstString GetDisplayDemangledName() const;
136 
137   void SetDemangledName(ConstString name) { m_demangled = name; }
138 
139   void SetMangledName(ConstString name) { m_mangled = name; }
140 
141   /// Mangled name get accessor.
142   ///
143   /// \return
144   ///     A reference to the mangled name string object.
145   ConstString &GetMangledName() { return m_mangled; }
146 
147   /// Mangled name get accessor.
148   ///
149   /// \return
150   ///     A const reference to the mangled name string object.
151   ConstString GetMangledName() const { return m_mangled; }
152 
153   /// Best name get accessor.
154   ///
155   /// \param[in] preference
156   ///     Which name would you prefer to get?
157   ///
158   /// \return
159   ///     A const reference to the preferred name string object if this
160   ///     object has a valid name of that kind, else a const reference to the
161   ///     other name is returned.
162   ConstString GetName(NamePreference preference = ePreferDemangled) const;
163 
164   /// Check if "name" matches either the mangled or demangled name.
165   ///
166   /// \param[in] name
167   ///     A name to match against both strings.
168   ///
169   /// \return
170   ///     \b True if \a name matches either name, \b false otherwise.
171   bool NameMatches(ConstString name) const {
172     if (m_mangled == name)
173       return true;
174     return GetDemangledName() == name;
175   }
176   bool NameMatches(const RegularExpression &regex) const;
177 
178   /// Get the memory cost of this object.
179   ///
180   /// Return the size in bytes that this object takes in memory. This returns
181   /// the size in bytes of this object, not any shared string values it may
182   /// refer to.
183   ///
184   /// \return
185   ///     The number of bytes that this object occupies in memory.
186   size_t MemorySize() const;
187 
188   /// Set the string value in this object.
189   ///
190   /// This version auto detects if the string is mangled by inspecting the
191   /// string value and looking for common mangling prefixes.
192   ///
193   /// \param[in] name
194   ///     The already const version of the name for this object.
195   void SetValue(ConstString name);
196 
197   /// Try to guess the language from the mangling.
198   ///
199   /// For a mangled name to have a language it must have both a mangled and a
200   /// demangled name and it can be guessed from the mangling what the language
201   /// is.  Note: this will return C++ for any language that uses Itanium ABI
202   /// mangling.
203   ///
204   /// Standard C function names will return eLanguageTypeUnknown because they
205   /// aren't mangled and it isn't clear what language the name represents
206   /// (there will be no mangled name).
207   ///
208   /// \return
209   ///     The language for the mangled/demangled name, eLanguageTypeUnknown
210   ///     if there is no mangled or demangled counterpart.
211   lldb::LanguageType GuessLanguage() const;
212 
213   /// Function signature for filtering mangled names.
214   using SkipMangledNameFn = bool(llvm::StringRef, ManglingScheme);
215 
216   /// Get rich mangling information. This is optimized for batch processing
217   /// while populating a name index. To get the pure demangled name string for
218   /// a single entity, use GetDemangledName() instead.
219   ///
220   /// For names that match the Itanium mangling scheme, this uses LLVM's
221   /// ItaniumPartialDemangler. All other names fall back to LLDB's builtin
222   /// parser currently.
223   ///
224   /// This function is thread-safe when used with different \a context
225   /// instances in different threads.
226   ///
227   /// \param[in] context
228   ///     The context for this function. A single instance can be stack-
229   ///     allocated in the caller's frame and used for multiple calls.
230   ///
231   /// \param[in] skip_mangled_name
232   ///     A filtering function for skipping entities based on name and mangling
233   ///     scheme. This can be null if unused.
234   ///
235   /// \return
236   ///     True on success, false otherwise.
237   bool GetRichManglingInfo(RichManglingContext &context,
238                            SkipMangledNameFn *skip_mangled_name);
239 
240   /// Try to identify the mangling scheme used.
241   /// \param[in] name
242   ///     The name we are attempting to identify the mangling scheme for.
243   ///
244   /// \return
245   ///     eManglingSchemeNone if no known mangling scheme could be identified
246   ///     for s, otherwise the enumerator for the mangling scheme detected.
247   static Mangled::ManglingScheme GetManglingScheme(llvm::StringRef const name);
248 
249   /// Decode a serialized version of this object from data.
250   ///
251   /// \param data
252   ///   The decoder object that references the serialized data.
253   ///
254   /// \param offset_ptr
255   ///   A pointer that contains the offset from which the data will be decoded
256   ///   from that gets updated as data gets decoded.
257   ///
258   /// \param strtab
259   ///   All strings in cache files are put into string tables for efficiency
260   ///   and cache file size reduction. Strings are stored as uint32_t string
261   ///   table offsets in the cache data.
262   bool Decode(const DataExtractor &data, lldb::offset_t *offset_ptr,
263               const StringTableReader &strtab);
264 
265   /// Encode this object into a data encoder object.
266   ///
267   /// This allows this object to be serialized to disk.
268   ///
269   /// \param encoder
270   ///   A data encoder object that serialized bytes will be encoded into.
271   ///
272   /// \param strtab
273   ///   All strings in cache files are put into string tables for efficiency
274   ///   and cache file size reduction. Strings are stored as uint32_t string
275   ///   table offsets in the cache data.
276   void Encode(DataEncoder &encoder, ConstStringTable &strtab) const;
277 
278 private:
279   /// Mangled member variables.
280   ConstString m_mangled;           ///< The mangled version of the name
281   mutable ConstString m_demangled; ///< Mutable so we can get it on demand with
282                                    ///a const version of this object
283 };
284 
285 Stream &operator<<(Stream &s, const Mangled &obj);
286 
287 } // namespace lldb_private
288 
289 #endif // LLDB_CORE_MANGLED_H
290