1 //===-- Module.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 liblldb_Module_h_
10 #define liblldb_Module_h_
11 
12 #include "lldb/Core/Address.h"
13 #include "lldb/Core/ModuleSpec.h"
14 #include "lldb/Symbol/ObjectFile.h"
15 #include "lldb/Symbol/SymbolContextScope.h"
16 #include "lldb/Symbol/TypeSystem.h"
17 #include "lldb/Target/PathMappingList.h"
18 #include "lldb/Utility/ArchSpec.h"
19 #include "lldb/Utility/ConstString.h"
20 #include "lldb/Utility/FileSpec.h"
21 #include "lldb/Utility/Status.h"
22 #include "lldb/Utility/UUID.h"
23 #include "lldb/lldb-defines.h"
24 #include "lldb/lldb-enumerations.h"
25 #include "lldb/lldb-forward.h"
26 #include "lldb/lldb-types.h"
27 
28 #include "llvm/ADT/DenseSet.h"
29 #include "llvm/ADT/StringRef.h"
30 #include "llvm/Support/Chrono.h"
31 
32 #include <atomic>
33 #include <memory>
34 #include <mutex>
35 #include <stddef.h>
36 #include <stdint.h>
37 #include <string>
38 #include <vector>
39 
40 namespace lldb_private {
41 class CompilerDeclContext;
42 class Function;
43 class Log;
44 class ObjectFile;
45 class RegularExpression;
46 class SectionList;
47 class Stream;
48 class Symbol;
49 class SymbolContext;
50 class SymbolContextList;
51 class SymbolFile;
52 class Symtab;
53 class Target;
54 class TypeList;
55 class TypeMap;
56 class VariableList;
57 
58 /// \class Module Module.h "lldb/Core/Module.h"
59 /// A class that describes an executable image and its associated
60 ///        object and symbol files.
61 ///
62 /// The module is designed to be able to select a single slice of an
63 /// executable image as it would appear on disk and during program execution.
64 ///
65 /// Modules control when and if information is parsed according to which
66 /// accessors are called. For example the object file (ObjectFile)
67 /// representation will only be parsed if the object file is requested using
68 /// the Module::GetObjectFile() is called. The debug symbols will only be
69 /// parsed if the symbol file (SymbolFile) is requested using the
70 /// Module::GetSymbolFile() method.
71 ///
72 /// The module will parse more detailed information as more queries are made.
73 class Module : public std::enable_shared_from_this<Module>,
74                public SymbolContextScope {
75 public:
76   // Static functions that can track the lifetime of module objects. This is
77   // handy because we might have Module objects that are in shared pointers
78   // that aren't in the global module list (from ModuleList). If this is the
79   // case we need to know about it. The modules in the global list maintained
80   // by these functions can be viewed using the "target modules list" command
81   // using the "--global" (-g for short).
82   static size_t GetNumberAllocatedModules();
83 
84   static Module *GetAllocatedModuleAtIndex(size_t idx);
85 
86   static std::recursive_mutex &GetAllocationModuleCollectionMutex();
87 
88   /// Construct with file specification and architecture.
89   ///
90   /// Clients that wish to share modules with other targets should use
91   /// ModuleList::GetSharedModule().
92   ///
93   /// \param[in] file_spec
94   ///     The file specification for the on disk representation of
95   ///     this executable image.
96   ///
97   /// \param[in] arch
98   ///     The architecture to set as the current architecture in
99   ///     this module.
100   ///
101   /// \param[in] object_name
102   ///     The name of an object in a module used to extract a module
103   ///     within a module (.a files and modules that contain multiple
104   ///     architectures).
105   ///
106   /// \param[in] object_offset
107   ///     The offset within an existing module used to extract a
108   ///     module within a module (.a files and modules that contain
109   ///     multiple architectures).
110   Module(
111       const FileSpec &file_spec, const ArchSpec &arch,
112       const ConstString *object_name = nullptr,
113       lldb::offset_t object_offset = 0,
114       const llvm::sys::TimePoint<> &object_mod_time = llvm::sys::TimePoint<>());
115 
116   Module(const ModuleSpec &module_spec);
117 
118   template <typename ObjFilePlugin, typename... Args>
119   static lldb::ModuleSP CreateModuleFromObjectFile(Args &&... args) {
120     // Must create a module and place it into a shared pointer before we can
121     // create an object file since it has a std::weak_ptr back to the module,
122     // so we need to control the creation carefully in this static function
123     lldb::ModuleSP module_sp(new Module());
124     module_sp->m_objfile_sp =
125         std::make_shared<ObjFilePlugin>(module_sp, std::forward<Args>(args)...);
126     module_sp->m_did_load_objfile.store(true, std::memory_order_relaxed);
127 
128     // Once we get the object file, set module ArchSpec to the one we get from
129     // the object file. If the object file does not have an architecture, we
130     // consider the creation a failure.
131     ArchSpec arch = module_sp->m_objfile_sp->GetArchitecture();
132     if (!arch)
133       return nullptr;
134     module_sp->m_arch = arch;
135 
136     // Also copy the object file's FileSpec.
137     module_sp->m_file = module_sp->m_objfile_sp->GetFileSpec();
138     return module_sp;
139   }
140 
141   /// Destructor.
142   ~Module() override;
143 
144   bool MatchesModuleSpec(const ModuleSpec &module_ref);
145 
146   /// Set the load address for all sections in a module to be the file address
147   /// plus \a slide.
148   ///
149   /// Many times a module will be loaded in a target with a constant offset
150   /// applied to all top level sections. This function can set the load
151   /// address for all top level sections to be the section file address +
152   /// offset.
153   ///
154   /// \param[in] target
155   ///     The target in which to apply the section load addresses.
156   ///
157   /// \param[in] value
158   ///     if \a value_is_offset is true, then value is the offset to
159   ///     apply to all file addresses for all top level sections in
160   ///     the object file as each section load address is being set.
161   ///     If \a value_is_offset is false, then "value" is the new
162   ///     absolute base address for the image.
163   ///
164   /// \param[in] value_is_offset
165   ///     If \b true, then \a value is an offset to apply to each
166   ///     file address of each top level section.
167   ///     If \b false, then \a value is the image base address that
168   ///     will be used to rigidly slide all loadable sections.
169   ///
170   /// \param[out] changed
171   ///     If any section load addresses were changed in \a target,
172   ///     then \a changed will be set to \b true. Else \a changed
173   ///     will be set to false. This allows this function to be
174   ///     called multiple times on the same module for the same
175   ///     target. If the module hasn't moved, then \a changed will
176   ///     be false and no module updated notification will need to
177   ///     be sent out.
178   ///
179   /// \return
180   ///     /b True if any sections were successfully loaded in \a target,
181   ///     /b false otherwise.
182   bool SetLoadAddress(Target &target, lldb::addr_t value, bool value_is_offset,
183                       bool &changed);
184 
185   /// \copydoc SymbolContextScope::CalculateSymbolContext(SymbolContext*)
186   ///
187   /// \see SymbolContextScope
188   void CalculateSymbolContext(SymbolContext *sc) override;
189 
190   lldb::ModuleSP CalculateSymbolContextModule() override;
191 
192   void
193   GetDescription(llvm::raw_ostream &s,
194                  lldb::DescriptionLevel level = lldb::eDescriptionLevelFull);
195 
196   /// Get the module path and object name.
197   ///
198   /// Modules can refer to object files. In this case the specification is
199   /// simple and would return the path to the file:
200   ///
201   ///     "/usr/lib/foo.dylib"
202   ///
203   /// Modules can be .o files inside of a BSD archive (.a file). In this case,
204   /// the object specification will look like:
205   ///
206   ///     "/usr/lib/foo.a(bar.o)"
207   ///
208   /// There are many places where logging wants to log this fully qualified
209   /// specification, so we centralize this functionality here.
210   ///
211   /// \return
212   ///     The object path + object name if there is one.
213   std::string GetSpecificationDescription() const;
214 
215   /// Dump a description of this object to a Stream.
216   ///
217   /// Dump a description of the contents of this object to the supplied stream
218   /// \a s. The dumped content will be only what has been loaded or parsed up
219   /// to this point at which this function is called, so this is a good way to
220   /// see what has been parsed in a module.
221   ///
222   /// \param[in] s
223   ///     The stream to which to dump the object description.
224   void Dump(Stream *s);
225 
226   /// \copydoc SymbolContextScope::DumpSymbolContext(Stream*)
227   ///
228   /// \see SymbolContextScope
229   void DumpSymbolContext(Stream *s) override;
230 
231   /// Find a symbol in the object file's symbol table.
232   ///
233   /// \param[in] name
234   ///     The name of the symbol that we are looking for.
235   ///
236   /// \param[in] symbol_type
237   ///     If set to eSymbolTypeAny, find a symbol of any type that
238   ///     has a name that matches \a name. If set to any other valid
239   ///     SymbolType enumeration value, then search only for
240   ///     symbols that match \a symbol_type.
241   ///
242   /// \return
243   ///     Returns a valid symbol pointer if a symbol was found,
244   ///     nullptr otherwise.
245   const Symbol *FindFirstSymbolWithNameAndType(
246       ConstString name,
247       lldb::SymbolType symbol_type = lldb::eSymbolTypeAny);
248 
249   void FindSymbolsWithNameAndType(ConstString name,
250                                   lldb::SymbolType symbol_type,
251                                   SymbolContextList &sc_list);
252 
253   void FindSymbolsMatchingRegExAndType(const RegularExpression &regex,
254                                        lldb::SymbolType symbol_type,
255                                        SymbolContextList &sc_list);
256 
257   /// Find a function symbols in the object file's symbol table.
258   ///
259   /// \param[in] name
260   ///     The name of the symbol that we are looking for.
261   ///
262   /// \param[in] name_type_mask
263   ///     A mask that has one or more bitwise OR'ed values from the
264   ///     lldb::FunctionNameType enumeration type that indicate what
265   ///     kind of names we are looking for.
266   ///
267   /// \param[out] sc_list
268   ///     A list to append any matching symbol contexts to.
269   void FindFunctionSymbols(ConstString name, uint32_t name_type_mask,
270                            SymbolContextList &sc_list);
271 
272   /// Find compile units by partial or full path.
273   ///
274   /// Finds all compile units that match \a path in all of the modules and
275   /// returns the results in \a sc_list.
276   ///
277   /// \param[in] path
278   ///     The name of the function we are looking for.
279   ///
280   /// \param[out] sc_list
281   ///     A symbol context list that gets filled in with all of the
282   ///     matches.
283   void FindCompileUnits(const FileSpec &path, SymbolContextList &sc_list);
284 
285   /// Find functions by name.
286   ///
287   /// If the function is an inlined function, it will have a block,
288   /// representing the inlined function, and the function will be the
289   /// containing function.  If it is not inlined, then the block will be NULL.
290   ///
291   /// \param[in] name
292   ///     The name of the compile unit we are looking for.
293   ///
294   /// \param[in] name_type_mask
295   ///     A bit mask of bits that indicate what kind of names should
296   ///     be used when doing the lookup. Bits include fully qualified
297   ///     names, base names, C++ methods, or ObjC selectors.
298   ///     See FunctionNameType for more details.
299   ///
300   /// \param[out] sc_list
301   ///     A symbol context list that gets filled in with all of the
302   ///     matches.
303   void FindFunctions(ConstString name,
304                      const CompilerDeclContext *parent_decl_ctx,
305                      lldb::FunctionNameType name_type_mask, bool symbols_ok,
306                      bool inlines_ok, SymbolContextList &sc_list);
307 
308   /// Find functions by name.
309   ///
310   /// If the function is an inlined function, it will have a block,
311   /// representing the inlined function, and the function will be the
312   /// containing function.  If it is not inlined, then the block will be NULL.
313   ///
314   /// \param[in] regex
315   ///     A regular expression to use when matching the name.
316   ///
317   /// \param[out] sc_list
318   ///     A symbol context list that gets filled in with all of the
319   ///     matches.
320   void FindFunctions(const RegularExpression &regex, bool symbols_ok,
321                      bool inlines_ok, SymbolContextList &sc_list);
322 
323   /// Find addresses by file/line
324   ///
325   /// \param[in] target_sp
326   ///     The target the addresses are desired for.
327   ///
328   /// \param[in] file
329   ///     Source file to locate.
330   ///
331   /// \param[in] line
332   ///     Source line to locate.
333   ///
334   /// \param[in] function
335   ///	    Optional filter function. Addresses within this function will be
336   ///     added to the 'local' list. All others will be added to the 'extern'
337   ///     list.
338   ///
339   /// \param[out] output_local
340   ///     All matching addresses within 'function'
341   ///
342   /// \param[out] output_extern
343   ///     All matching addresses not within 'function'
344   void FindAddressesForLine(const lldb::TargetSP target_sp,
345                             const FileSpec &file, uint32_t line,
346                             Function *function,
347                             std::vector<Address> &output_local,
348                             std::vector<Address> &output_extern);
349 
350   /// Find global and static variables by name.
351   ///
352   /// \param[in] name
353   ///     The name of the global or static variable we are looking
354   ///     for.
355   ///
356   /// \param[in] parent_decl_ctx
357   ///     If valid, a decl context that results must exist within
358   ///
359   /// \param[in] max_matches
360   ///     Allow the number of matches to be limited to \a
361   ///     max_matches. Specify UINT32_MAX to get all possible matches.
362   ///
363   /// \param[in] variable_list
364   ///     A list of variables that gets the matches appended to.
365   ///
366   void FindGlobalVariables(ConstString name,
367                            const CompilerDeclContext *parent_decl_ctx,
368                            size_t max_matches, VariableList &variable_list);
369 
370   /// Find global and static variables by regular expression.
371   ///
372   /// \param[in] regex
373   ///     A regular expression to use when matching the name.
374   ///
375   /// \param[in] max_matches
376   ///     Allow the number of matches to be limited to \a
377   ///     max_matches. Specify UINT32_MAX to get all possible matches.
378   ///
379   /// \param[in] variable_list
380   ///     A list of variables that gets the matches appended to.
381   ///
382   void FindGlobalVariables(const RegularExpression &regex, size_t max_matches,
383                            VariableList &variable_list);
384 
385   /// Find types by name.
386   ///
387   /// Type lookups in modules go through the SymbolFile. The SymbolFile needs to
388   /// be able to lookup types by basename and not the fully qualified typename.
389   /// This allows the type accelerator tables to stay small, even with heavily
390   /// templatized C++. The type search will then narrow down the search
391   /// results. If "exact_match" is true, then the type search will only match
392   /// exact type name matches. If "exact_match" is false, the type will match
393   /// as long as the base typename matches and as long as any immediate
394   /// containing namespaces/class scopes that are specified match. So to
395   /// search for a type "d" in "b::c", the name "b::c::d" can be specified and
396   /// it will match any class/namespace "b" which contains a class/namespace
397   /// "c" which contains type "d". We do this to allow users to not always
398   /// have to specify complete scoping on all expressions, but it also allows
399   /// for exact matching when required.
400   ///
401   /// \param[in] type_name
402   ///     The name of the type we are looking for that is a fully
403   ///     or partially qualified type name.
404   ///
405   /// \param[in] exact_match
406   ///     If \b true, \a type_name is fully qualified and must match
407   ///     exactly. If \b false, \a type_name is a partially qualified
408   ///     name where the leading namespaces or classes can be
409   ///     omitted to make finding types that a user may type
410   ///     easier.
411   ///
412   /// \param[out] types
413   ///     A type list gets populated with any matches.
414   ///
415   void
416   FindTypes(ConstString type_name, bool exact_match, size_t max_matches,
417             llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files,
418             TypeList &types);
419 
420   /// Find types by name.
421   ///
422   /// This behaves like the other FindTypes method but allows to
423   /// specify a DeclContext and a language for the type being searched
424   /// for.
425   ///
426   /// \param searched_symbol_files
427   ///     Prevents one file from being visited multiple times.
428   void FindTypes(llvm::ArrayRef<CompilerContext> pattern, LanguageSet languages,
429                  llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files,
430                  TypeMap &types);
431 
432   lldb::TypeSP FindFirstType(const SymbolContext &sc,
433                              ConstString type_name, bool exact_match);
434 
435   /// Find types by name that are in a namespace. This function is used by the
436   /// expression parser when searches need to happen in an exact namespace
437   /// scope.
438   ///
439   /// \param[in] type_name
440   ///     The name of a type within a namespace that should not include
441   ///     any qualifying namespaces (just a type basename).
442   ///
443   /// \param[out] type_list
444   ///     A type list gets populated with any matches.
445   void FindTypesInNamespace(ConstString type_name,
446                             const CompilerDeclContext *parent_decl_ctx,
447                             size_t max_matches, TypeList &type_list);
448 
449   /// Get const accessor for the module architecture.
450   ///
451   /// \return
452   ///     A const reference to the architecture object.
453   const ArchSpec &GetArchitecture() const;
454 
455   /// Get const accessor for the module file specification.
456   ///
457   /// This function returns the file for the module on the host system that is
458   /// running LLDB. This can differ from the path on the platform since we
459   /// might be doing remote debugging.
460   ///
461   /// \return
462   ///     A const reference to the file specification object.
463   const FileSpec &GetFileSpec() const { return m_file; }
464 
465   /// Get accessor for the module platform file specification.
466   ///
467   /// Platform file refers to the path of the module as it is known on the
468   /// remote system on which it is being debugged. For local debugging this is
469   /// always the same as Module::GetFileSpec(). But remote debugging might
470   /// mention a file "/usr/lib/liba.dylib" which might be locally downloaded
471   /// and cached. In this case the platform file could be something like:
472   /// "/tmp/lldb/platform-cache/remote.host.computer/usr/lib/liba.dylib" The
473   /// file could also be cached in a local developer kit directory.
474   ///
475   /// \return
476   ///     A const reference to the file specification object.
477   const FileSpec &GetPlatformFileSpec() const {
478     if (m_platform_file)
479       return m_platform_file;
480     return m_file;
481   }
482 
483   void SetPlatformFileSpec(const FileSpec &file) { m_platform_file = file; }
484 
485   const FileSpec &GetRemoteInstallFileSpec() const {
486     return m_remote_install_file;
487   }
488 
489   void SetRemoteInstallFileSpec(const FileSpec &file) {
490     m_remote_install_file = file;
491   }
492 
493   const FileSpec &GetSymbolFileFileSpec() const { return m_symfile_spec; }
494 
495   void PreloadSymbols();
496 
497   void SetSymbolFileFileSpec(const FileSpec &file);
498 
499   const llvm::sys::TimePoint<> &GetModificationTime() const {
500     return m_mod_time;
501   }
502 
503   const llvm::sys::TimePoint<> &GetObjectModificationTime() const {
504     return m_object_mod_time;
505   }
506 
507   void SetObjectModificationTime(const llvm::sys::TimePoint<> &mod_time) {
508     m_mod_time = mod_time;
509   }
510 
511   /// Tells whether this module is capable of being the main executable for a
512   /// process.
513   ///
514   /// \return
515   ///     \b true if it is, \b false otherwise.
516   bool IsExecutable();
517 
518   /// Tells whether this module has been loaded in the target passed in. This
519   /// call doesn't distinguish between whether the module is loaded by the
520   /// dynamic loader, or by a "target module add" type call.
521   ///
522   /// \param[in] target
523   ///    The target to check whether this is loaded in.
524   ///
525   /// \return
526   ///     \b true if it is, \b false otherwise.
527   bool IsLoadedInTarget(Target *target);
528 
529   bool LoadScriptingResourceInTarget(Target *target, Status &error,
530                                      Stream *feedback_stream = nullptr);
531 
532   /// Get the number of compile units for this module.
533   ///
534   /// \return
535   ///     The number of compile units that the symbol vendor plug-in
536   ///     finds.
537   size_t GetNumCompileUnits();
538 
539   lldb::CompUnitSP GetCompileUnitAtIndex(size_t idx);
540 
541   ConstString GetObjectName() const;
542 
543   uint64_t GetObjectOffset() const { return m_object_offset; }
544 
545   /// Get the object file representation for the current architecture.
546   ///
547   /// If the object file has not been located or parsed yet, this function
548   /// will find the best ObjectFile plug-in that can parse Module::m_file.
549   ///
550   /// \return
551   ///     If Module::m_file does not exist, or no plug-in was found
552   ///     that can parse the file, or the object file doesn't contain
553   ///     the current architecture in Module::m_arch, nullptr will be
554   ///     returned, else a valid object file interface will be
555   ///     returned. The returned pointer is owned by this object and
556   ///     remains valid as long as the object is around.
557   virtual ObjectFile *GetObjectFile();
558 
559   /// Get the unified section list for the module. This is the section list
560   /// created by the module's object file and any debug info and symbol files
561   /// created by the symbol vendor.
562   ///
563   /// If the symbol vendor has not been loaded yet, this function will return
564   /// the section list for the object file.
565   ///
566   /// \return
567   ///     Unified module section list.
568   virtual SectionList *GetSectionList();
569 
570   /// Notify the module that the file addresses for the Sections have been
571   /// updated.
572   ///
573   /// If the Section file addresses for a module are updated, this method
574   /// should be called.  Any parts of the module, object file, or symbol file
575   /// that has cached those file addresses must invalidate or update its
576   /// cache.
577   virtual void SectionFileAddressesChanged();
578 
579   /// Returns a reference to the UnwindTable for this Module
580   ///
581   /// The UnwindTable contains FuncUnwinders objects for any function in this
582   /// Module.  If a FuncUnwinders object hasn't been created yet (i.e. the
583   /// function has yet to be unwound in a stack walk), it will be created when
584   /// requested.  Specifically, we do not create FuncUnwinders objects for
585   /// functions until they are needed.
586   ///
587   /// \return
588   ///     Returns the unwind table for this module. If this object has no
589   ///     associated object file, an empty UnwindTable is returned.
590   UnwindTable &GetUnwindTable();
591 
592   llvm::VersionTuple GetVersion();
593 
594   /// Load an object file from memory.
595   ///
596   /// If available, the size of the object file in memory may be passed to
597   /// avoid additional round trips to process memory. If the size is not
598   /// provided, a default value is used. This value should be large enough to
599   /// enable the ObjectFile plugins to read the header of the object file
600   /// without going back to the process.
601   ///
602   /// \return
603   ///     The object file loaded from memory or nullptr, if the operation
604   ///     failed (see the `error` for more information in that case).
605   ObjectFile *GetMemoryObjectFile(const lldb::ProcessSP &process_sp,
606                                   lldb::addr_t header_addr, Status &error,
607                                   size_t size_to_read = 512);
608 
609   /// Get the module's symbol file
610   ///
611   /// If the symbol file has already been loaded, this function returns it. All
612   /// arguments are ignored. If the symbol file has not been located yet, and
613   /// the can_create argument is false, the function returns nullptr. If
614   /// can_create is true, this function will find the best SymbolFile plug-in
615   /// that can use the current object file. feedback_strm, if not null, is used
616   /// to report the details of the search process.
617   virtual SymbolFile *GetSymbolFile(bool can_create = true,
618                                     Stream *feedback_strm = nullptr);
619 
620   Symtab *GetSymtab();
621 
622   /// Get a reference to the UUID value contained in this object.
623   ///
624   /// If the executable image file doesn't not have a UUID value built into
625   /// the file format, an MD5 checksum of the entire file, or slice of the
626   /// file for the current architecture should be used.
627   ///
628   /// \return
629   ///     A const pointer to the internal copy of the UUID value in
630   ///     this module if this module has a valid UUID value, NULL
631   ///     otherwise.
632   const lldb_private::UUID &GetUUID();
633 
634   /// A debugging function that will cause everything in a module to
635   /// be parsed.
636   ///
637   /// All compile units will be parsed, along with all globals and static
638   /// variables and all functions for those compile units. All types, scopes,
639   /// local variables, static variables, global variables, and line tables
640   /// will be parsed. This can be used prior to dumping a module to see a
641   /// complete list of the resulting debug information that gets parsed, or as
642   /// a debug function to ensure that the module can consume all of the debug
643   /// data the symbol vendor provides.
644   void ParseAllDebugSymbols();
645 
646   bool ResolveFileAddress(lldb::addr_t vm_addr, Address &so_addr);
647 
648   /// Resolve the symbol context for the given address.
649   ///
650   /// Tries to resolve the matching symbol context based on a lookup from the
651   /// current symbol vendor.  If the lazy lookup fails, an attempt is made to
652   /// parse the eh_frame section to handle stripped symbols.  If this fails,
653   /// an attempt is made to resolve the symbol to the previous address to
654   /// handle the case of a function with a tail call.
655   ///
656   /// Use properties of the modified SymbolContext to inspect any resolved
657   /// target, module, compilation unit, symbol, function, function block or
658   /// line entry.  Use the return value to determine which of these properties
659   /// have been modified.
660   ///
661   /// \param[in] so_addr
662   ///     A load address to resolve.
663   ///
664   /// \param[in] resolve_scope
665   ///     The scope that should be resolved (see SymbolContext::Scope).
666   ///     A combination of flags from the enumeration SymbolContextItem
667   ///     requesting a resolution depth.  Note that the flags that are
668   ///     actually resolved may be a superset of the requested flags.
669   ///     For instance, eSymbolContextSymbol requires resolution of
670   ///     eSymbolContextModule, and eSymbolContextFunction requires
671   ///     eSymbolContextSymbol.
672   ///
673   /// \param[out] sc
674   ///     The SymbolContext that is modified based on symbol resolution.
675   ///
676   /// \param[in] resolve_tail_call_address
677   ///     Determines if so_addr should resolve to a symbol in the case
678   ///     of a function whose last instruction is a call.  In this case,
679   ///     the PC can be one past the address range of the function.
680   ///
681   /// \return
682   ///     The scope that has been resolved (see SymbolContext::Scope).
683   ///
684   /// \see SymbolContext::Scope
685   uint32_t ResolveSymbolContextForAddress(
686       const Address &so_addr, lldb::SymbolContextItem resolve_scope,
687       SymbolContext &sc, bool resolve_tail_call_address = false);
688 
689   /// Resolve items in the symbol context for a given file and line.
690   ///
691   /// Tries to resolve \a file_path and \a line to a list of matching symbol
692   /// contexts.
693   ///
694   /// The line table entries contains addresses that can be used to further
695   /// resolve the values in each match: the function, block, symbol. Care
696   /// should be taken to minimize the amount of information that is requested
697   /// to only what is needed -- typically the module, compile unit, line table
698   /// and line table entry are sufficient.
699   ///
700   /// \param[in] file_path
701   ///     A path to a source file to match. If \a file_path does not
702   ///     specify a directory, then this query will match all files
703   ///     whose base filename matches. If \a file_path does specify
704   ///     a directory, the fullpath to the file must match.
705   ///
706   /// \param[in] line
707   ///     The source line to match, or zero if just the compile unit
708   ///     should be resolved.
709   ///
710   /// \param[in] check_inlines
711   ///     Check for inline file and line number matches. This option
712   ///     should be used sparingly as it will cause all line tables
713   ///     for every compile unit to be parsed and searched for
714   ///     matching inline file entries.
715   ///
716   /// \param[in] resolve_scope
717   ///     The scope that should be resolved (see
718   ///     SymbolContext::Scope).
719   ///
720   /// \param[out] sc_list
721   ///     A symbol context list that gets matching symbols contexts
722   ///     appended to.
723   ///
724   /// \return
725   ///     The number of matches that were added to \a sc_list.
726   ///
727   /// \see SymbolContext::Scope
728   uint32_t ResolveSymbolContextForFilePath(
729       const char *file_path, uint32_t line, bool check_inlines,
730       lldb::SymbolContextItem resolve_scope, SymbolContextList &sc_list);
731 
732   /// Resolve items in the symbol context for a given file and line.
733   ///
734   /// Tries to resolve \a file_spec and \a line to a list of matching symbol
735   /// contexts.
736   ///
737   /// The line table entries contains addresses that can be used to further
738   /// resolve the values in each match: the function, block, symbol. Care
739   /// should be taken to minimize the amount of information that is requested
740   /// to only what is needed -- typically the module, compile unit, line table
741   /// and line table entry are sufficient.
742   ///
743   /// \param[in] file_spec
744   ///     A file spec to a source file to match. If \a file_path does
745   ///     not specify a directory, then this query will match all
746   ///     files whose base filename matches. If \a file_path does
747   ///     specify a directory, the fullpath to the file must match.
748   ///
749   /// \param[in] line
750   ///     The source line to match, or zero if just the compile unit
751   ///     should be resolved.
752   ///
753   /// \param[in] check_inlines
754   ///     Check for inline file and line number matches. This option
755   ///     should be used sparingly as it will cause all line tables
756   ///     for every compile unit to be parsed and searched for
757   ///     matching inline file entries.
758   ///
759   /// \param[in] resolve_scope
760   ///     The scope that should be resolved (see
761   ///     SymbolContext::Scope).
762   ///
763   /// \param[out] sc_list
764   ///     A symbol context list that gets filled in with all of the
765   ///     matches.
766   ///
767   /// \return
768   ///     A integer that contains SymbolContext::Scope bits set for
769   ///     each item that was successfully resolved.
770   ///
771   /// \see SymbolContext::Scope
772   uint32_t ResolveSymbolContextsForFileSpec(
773       const FileSpec &file_spec, uint32_t line, bool check_inlines,
774       lldb::SymbolContextItem resolve_scope, SymbolContextList &sc_list);
775 
776   void SetFileSpecAndObjectName(const FileSpec &file,
777                                 ConstString object_name);
778 
779   bool GetIsDynamicLinkEditor();
780 
781   llvm::Expected<TypeSystem &>
782   GetTypeSystemForLanguage(lldb::LanguageType language);
783 
784   // Special error functions that can do printf style formatting that will
785   // prepend the message with something appropriate for this module (like the
786   // architecture, path and object name (if any)). This centralizes code so
787   // that everyone doesn't need to format their error and log messages on their
788   // own and keeps the output a bit more consistent.
789   void LogMessage(Log *log, const char *format, ...)
790       __attribute__((format(printf, 3, 4)));
791 
792   void LogMessageVerboseBacktrace(Log *log, const char *format, ...)
793       __attribute__((format(printf, 3, 4)));
794 
795   void ReportWarning(const char *format, ...)
796       __attribute__((format(printf, 2, 3)));
797 
798   void ReportError(const char *format, ...)
799       __attribute__((format(printf, 2, 3)));
800 
801   // Only report an error once when the module is first detected to be modified
802   // so we don't spam the console with many messages.
803   void ReportErrorIfModifyDetected(const char *format, ...)
804       __attribute__((format(printf, 2, 3)));
805 
806   // Return true if the file backing this module has changed since the module
807   // was originally created  since we saved the initial file modification time
808   // when the module first gets created.
809   bool FileHasChanged() const;
810 
811   // SymbolFile and ObjectFile member objects should lock the
812   // module mutex to avoid deadlocks.
813   std::recursive_mutex &GetMutex() const { return m_mutex; }
814 
815   PathMappingList &GetSourceMappingList() { return m_source_mappings; }
816 
817   const PathMappingList &GetSourceMappingList() const {
818     return m_source_mappings;
819   }
820 
821   /// Finds a source file given a file spec using the module source path
822   /// remappings (if any).
823   ///
824   /// Tries to resolve \a orig_spec by checking the module source path
825   /// remappings. It makes sure the file exists, so this call can be expensive
826   /// if the remappings are on a network file system, so use this function
827   /// sparingly (not in a tight debug info parsing loop).
828   ///
829   /// \param[in] orig_spec
830   ///     The original source file path to try and remap.
831   ///
832   /// \param[out] new_spec
833   ///     The newly remapped filespec that is guaranteed to exist.
834   ///
835   /// \return
836   ///     /b true if \a orig_spec was successfully located and
837   ///     \a new_spec is filled in with an existing file spec,
838   ///     \b false otherwise.
839   bool FindSourceFile(const FileSpec &orig_spec, FileSpec &new_spec) const;
840 
841   /// Remaps a source file given \a path into \a new_path.
842   ///
843   /// Remaps \a path if any source remappings match. This function does NOT
844   /// stat the file system so it can be used in tight loops where debug info
845   /// is being parsed.
846   ///
847   /// \param[in] path
848   ///     The original source file path to try and remap.
849   ///
850   /// \param[out] new_path
851   ///     The newly remapped filespec that is may or may not exist.
852   ///
853   /// \return
854   ///     /b true if \a path was successfully located and \a new_path
855   ///     is filled in with a new source path, \b false otherwise.
856   bool RemapSourceFile(llvm::StringRef path, std::string &new_path) const;
857   bool RemapSourceFile(const char *, std::string &) const = delete;
858 
859   /// Update the ArchSpec to a more specific variant.
860   bool MergeArchitecture(const ArchSpec &arch_spec);
861 
862   /// \class LookupInfo Module.h "lldb/Core/Module.h"
863   /// A class that encapsulates name lookup information.
864   ///
865   /// Users can type a wide variety of partial names when setting breakpoints
866   /// by name or when looking for functions by name. The SymbolFile object is
867   /// only required to implement name lookup for function basenames and for
868   /// fully mangled names. This means if the user types in a partial name, we
869   /// must reduce this to a name lookup that will work with all SymbolFile
870   /// objects. So we might reduce a name lookup to look for a basename, and then
871   /// prune out any results that don't match.
872   ///
873   /// The "m_name" member variable represents the name as it was typed by the
874   /// user. "m_lookup_name" will be the name we actually search for through
875   /// the symbol or objects files. Lanaguage is included in case we need to
876   /// filter results by language at a later date. The "m_name_type_mask"
877   /// member variable tells us what kinds of names we are looking for and can
878   /// help us prune out unwanted results.
879   ///
880   /// Function lookups are done in Module.cpp, ModuleList.cpp and in
881   /// BreakpointResolverName.cpp and they all now use this class to do lookups
882   /// correctly.
883   class LookupInfo {
884   public:
885     LookupInfo()
886         : m_name(), m_lookup_name(), m_language(lldb::eLanguageTypeUnknown),
887           m_name_type_mask(lldb::eFunctionNameTypeNone),
888           m_match_name_after_lookup(false) {}
889 
890     LookupInfo(ConstString name, lldb::FunctionNameType name_type_mask,
891                lldb::LanguageType language);
892 
893     ConstString GetName() const { return m_name; }
894 
895     void SetName(ConstString name) { m_name = name; }
896 
897     ConstString GetLookupName() const { return m_lookup_name; }
898 
899     void SetLookupName(ConstString name) { m_lookup_name = name; }
900 
901     lldb::FunctionNameType GetNameTypeMask() const { return m_name_type_mask; }
902 
903     void SetNameTypeMask(lldb::FunctionNameType mask) {
904       m_name_type_mask = mask;
905     }
906 
907     void Prune(SymbolContextList &sc_list, size_t start_idx) const;
908 
909   protected:
910     /// What the user originally typed
911     ConstString m_name;
912 
913     /// The actual name will lookup when calling in the object or symbol file
914     ConstString m_lookup_name;
915 
916     /// Limit matches to only be for this language
917     lldb::LanguageType m_language;
918 
919     /// One or more bits from lldb::FunctionNameType that indicate what kind of
920     /// names we are looking for
921     lldb::FunctionNameType m_name_type_mask;
922 
923     ///< If \b true, then demangled names that match will need to contain
924     ///< "m_name" in order to be considered a match
925     bool m_match_name_after_lookup;
926   };
927 
928 protected:
929   // Member Variables
930   mutable std::recursive_mutex m_mutex; ///< A mutex to keep this object happy
931                                         ///in multi-threaded environments.
932 
933   /// The modification time for this module when it was created.
934   llvm::sys::TimePoint<> m_mod_time;
935 
936   ArchSpec m_arch;      ///< The architecture for this module.
937   UUID m_uuid; ///< Each module is assumed to have a unique identifier to help
938                ///match it up to debug symbols.
939   FileSpec m_file; ///< The file representation on disk for this module (if
940                    ///there is one).
941   FileSpec m_platform_file; ///< The path to the module on the platform on which
942                             ///it is being debugged
943   FileSpec m_remote_install_file; ///< If set when debugging on remote
944                                   ///platforms, this module will be installed at
945                                   ///this location
946   FileSpec m_symfile_spec;   ///< If this path is valid, then this is the file
947                              ///that _will_ be used as the symbol file for this
948                              ///module
949   ConstString m_object_name; ///< The name an object within this module that is
950                              ///selected, or empty of the module is represented
951                              ///by \a m_file.
952   uint64_t m_object_offset;
953   llvm::sys::TimePoint<> m_object_mod_time;
954   lldb::ObjectFileSP m_objfile_sp; ///< A shared pointer to the object file
955                                    ///parser for this module as it may or may
956                                    ///not be shared with the SymbolFile
957   llvm::Optional<UnwindTable> m_unwind_table; ///< Table of FuncUnwinders
958                                               /// objects created for this
959                                               /// Module's functions
960   lldb::SymbolVendorUP
961       m_symfile_up; ///< A pointer to the symbol vendor for this module.
962   std::vector<lldb::SymbolVendorUP>
963       m_old_symfiles; ///< If anyone calls Module::SetSymbolFileFileSpec() and
964                       ///changes the symbol file,
965   ///< we need to keep all old symbol files around in case anyone has type
966   ///references to them
967   TypeSystemMap m_type_system_map;   ///< A map of any type systems associated
968                                      ///with this module
969   PathMappingList m_source_mappings; ///< Module specific source remappings for
970                                      ///when you have debug info for a module
971                                      ///that doesn't match where the sources
972                                      ///currently are
973   lldb::SectionListUP m_sections_up; ///< Unified section list for module that
974                                      /// is used by the ObjectFile and and
975                                      /// ObjectFile instances for the debug info
976 
977   std::atomic<bool> m_did_load_objfile{false};
978   std::atomic<bool> m_did_load_symfile{false};
979   std::atomic<bool> m_did_set_uuid{false};
980   mutable bool m_file_has_changed : 1,
981       m_first_file_changed_log : 1; /// See if the module was modified after it
982                                     /// was initially opened.
983 
984   /// Resolve a file or load virtual address.
985   ///
986   /// Tries to resolve \a vm_addr as a file address (if \a
987   /// vm_addr_is_file_addr is true) or as a load address if \a
988   /// vm_addr_is_file_addr is false) in the symbol vendor. \a resolve_scope
989   /// indicates what clients wish to resolve and can be used to limit the
990   /// scope of what is parsed.
991   ///
992   /// \param[in] vm_addr
993   ///     The load virtual address to resolve.
994   ///
995   /// \param[in] vm_addr_is_file_addr
996   ///     If \b true, \a vm_addr is a file address, else \a vm_addr
997   ///     if a load address.
998   ///
999   /// \param[in] resolve_scope
1000   ///     The scope that should be resolved (see
1001   ///     SymbolContext::Scope).
1002   ///
1003   /// \param[out] so_addr
1004   ///     The section offset based address that got resolved if
1005   ///     any bits are returned.
1006   ///
1007   /// \param[out] sc
1008   //      The symbol context that has objects filled in. Each bit
1009   ///     in the \a resolve_scope pertains to a member in the \a sc.
1010   ///
1011   /// \return
1012   ///     A integer that contains SymbolContext::Scope bits set for
1013   ///     each item that was successfully resolved.
1014   ///
1015   /// \see SymbolContext::Scope
1016   uint32_t ResolveSymbolContextForAddress(lldb::addr_t vm_addr,
1017                                           bool vm_addr_is_file_addr,
1018                                           lldb::SymbolContextItem resolve_scope,
1019                                           Address &so_addr, SymbolContext &sc);
1020 
1021   void SymbolIndicesToSymbolContextList(Symtab *symtab,
1022                                         std::vector<uint32_t> &symbol_indexes,
1023                                         SymbolContextList &sc_list);
1024 
1025   bool SetArchitecture(const ArchSpec &new_arch);
1026 
1027   void SetUUID(const lldb_private::UUID &uuid);
1028 
1029   SectionList *GetUnifiedSectionList();
1030 
1031   friend class ModuleList;
1032   friend class ObjectFile;
1033   friend class SymbolFile;
1034 
1035 private:
1036   Module(); // Only used internally by CreateJITModule ()
1037 
1038   void FindTypes_Impl(
1039       ConstString name, const CompilerDeclContext *parent_decl_ctx,
1040       size_t max_matches,
1041       llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files,
1042       TypeMap &types);
1043 
1044   DISALLOW_COPY_AND_ASSIGN(Module);
1045 };
1046 
1047 } // namespace lldb_private
1048 
1049 #endif // liblldb_Module_h_
1050