1 //===-- Mangled.cpp ---------------------------------------------*- C++ -*-===//
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
7 //===----------------------------------------------------------------------===//
9 #include "lldb/Core/Mangled.h"
12 #include "lldb/Host/windows/windows.h"
15 #pragma comment(lib, "dbghelp.lib")
18 #include "lldb/Core/RichManglingContext.h"
19 #include "lldb/Utility/ConstString.h"
20 #include "lldb/Utility/Log.h"
21 #include "lldb/Utility/Logging.h"
22 #include "lldb/Utility/RegularExpression.h"
23 #include "lldb/Utility/Stream.h"
24 #include "lldb/Utility/Timer.h"
25 #include "lldb/lldb-enumerations.h"
27 #include "Plugins/Language/CPlusPlus/CPlusPlusLanguage.h"
28 #include "Plugins/Language/ObjC/ObjCLanguage.h"
30 #include "llvm/ADT/StringRef.h"
31 #include "llvm/Demangle/Demangle.h"
32 #include "llvm/Support/Compiler.h"
40 using namespace lldb_private;
43 static DWORD safeUndecorateName(const char *Mangled, char *Demangled,
44 DWORD DemangledLength) {
46 std::lock_guard<std::mutex> Lock(M);
47 return ::UnDecorateSymbolName(
48 Mangled, Demangled, DemangledLength,
49 UNDNAME_NO_ACCESS_SPECIFIERS | // Strip public, private, protected
51 UNDNAME_NO_ALLOCATION_LANGUAGE | // Strip __thiscall, __stdcall,
53 UNDNAME_NO_THROW_SIGNATURES | // Strip throw() specifications
54 UNDNAME_NO_MEMBER_TYPE | // Strip virtual, static, etc
56 UNDNAME_NO_MS_KEYWORDS // Strip all MS extension keywords
61 static inline Mangled::ManglingScheme cstring_mangling_scheme(const char *s) {
64 return Mangled::eManglingSchemeMSVC;
65 if (s[0] == '_' && s[1] == 'Z')
66 return Mangled::eManglingSchemeItanium;
68 return Mangled::eManglingSchemeNone;
71 static inline bool cstring_is_mangled(const char *s) {
72 return cstring_mangling_scheme(s) != Mangled::eManglingSchemeNone;
76 get_demangled_name_without_arguments(ConstString mangled,
77 ConstString demangled) {
78 // This pair is <mangled name, demangled name without function arguments>
79 static std::pair<ConstString, ConstString>
80 g_most_recent_mangled_to_name_sans_args;
82 // Need to have the mangled & demangled names we're currently examining as
83 // statics so we can return a const ref to them at the end of the func if we
84 // don't have anything better.
85 static ConstString g_last_mangled;
86 static ConstString g_last_demangled;
88 if (mangled && g_most_recent_mangled_to_name_sans_args.first == mangled) {
89 return g_most_recent_mangled_to_name_sans_args.second;
92 g_last_demangled = demangled;
93 g_last_mangled = mangled;
95 const char *mangled_name_cstr = mangled.GetCString();
97 if (demangled && mangled_name_cstr && mangled_name_cstr[0]) {
98 if (mangled_name_cstr[0] == '_' && mangled_name_cstr[1] == 'Z' &&
99 (mangled_name_cstr[2] != 'T' && // avoid virtual table, VTT structure,
100 // typeinfo structure, and typeinfo
102 mangled_name_cstr[2] != 'G' && // avoid guard variables
103 mangled_name_cstr[2] != 'Z')) // named local entities (if we eventually
104 // handle eSymbolTypeData, we will want
107 CPlusPlusLanguage::MethodName cxx_method(demangled);
108 if (!cxx_method.GetBasename().empty()) {
109 std::string shortname;
110 if (!cxx_method.GetContext().empty())
111 shortname = cxx_method.GetContext().str() + "::";
112 shortname += cxx_method.GetBasename().str();
113 ConstString result(shortname.c_str());
114 g_most_recent_mangled_to_name_sans_args.first = mangled;
115 g_most_recent_mangled_to_name_sans_args.second = result;
116 return g_most_recent_mangled_to_name_sans_args.second;
122 return g_last_demangled;
123 return g_last_mangled;
127 // Default constructor
128 Mangled::Mangled() : m_mangled(), m_demangled() {}
130 // Constructor with an optional string and a boolean indicating if it is the
132 Mangled::Mangled(ConstString s, bool mangled)
133 : m_mangled(), m_demangled() {
135 SetValue(s, mangled);
138 Mangled::Mangled(llvm::StringRef name, bool is_mangled) {
140 SetValue(ConstString(name), is_mangled);
143 Mangled::Mangled(ConstString s) : m_mangled(), m_demangled() {
148 Mangled::Mangled(llvm::StringRef name) {
150 SetValue(ConstString(name));
154 Mangled::~Mangled() {}
156 // Convert to pointer operator. This allows code to check any Mangled objects
157 // to see if they contain anything valid using code such as:
159 // Mangled mangled(...);
162 Mangled::operator void *() const {
163 return (m_mangled) ? const_cast<Mangled *>(this) : nullptr;
166 // Logical NOT operator. This allows code to check any Mangled objects to see
167 // if they are invalid using code such as:
169 // Mangled mangled(...);
172 bool Mangled::operator!() const { return !m_mangled; }
174 // Clear the mangled and demangled values.
175 void Mangled::Clear() {
180 // Compare the string values.
181 int Mangled::Compare(const Mangled &a, const Mangled &b) {
182 return ConstString::Compare(
183 a.GetName(lldb::eLanguageTypeUnknown, ePreferMangled),
184 b.GetName(lldb::eLanguageTypeUnknown, ePreferMangled));
187 // Set the string value in this objects. If "mangled" is true, then the mangled
188 // named is set with the new value in "s", else the demangled name is set.
189 void Mangled::SetValue(ConstString s, bool mangled) {
204 void Mangled::SetValue(ConstString name) {
206 if (cstring_is_mangled(name.GetCString())) {
219 // Local helpers for different demangling implementations.
220 static char *GetMSVCDemangledStr(const char *M) {
221 #if defined(_MSC_VER)
222 const size_t demangled_length = 2048;
223 char *demangled_cstr = static_cast<char *>(::malloc(demangled_length));
224 ::ZeroMemory(demangled_cstr, demangled_length);
225 DWORD result = safeUndecorateName(M, demangled_cstr, demangled_length);
227 if (Log *log = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_DEMANGLE)) {
228 if (demangled_cstr && demangled_cstr[0])
229 log->Printf("demangled msvc: %s -> \"%s\"", M, demangled_cstr);
231 log->Printf("demangled msvc: %s -> error: 0x%lu", M, result);
235 return demangled_cstr;
237 ::free(demangled_cstr);
245 static char *GetItaniumDemangledStr(const char *M) {
246 char *demangled_cstr = nullptr;
248 llvm::ItaniumPartialDemangler ipd;
249 bool err = ipd.partialDemangle(M);
251 // Default buffer and size (will realloc in case it's too small).
252 size_t demangled_size = 80;
253 demangled_cstr = static_cast<char *>(std::malloc(demangled_size));
254 demangled_cstr = ipd.finishDemangle(demangled_cstr, &demangled_size);
256 assert(demangled_cstr &&
257 "finishDemangle must always succeed if partialDemangle did");
258 assert(demangled_cstr[demangled_size - 1] == '\0' &&
259 "Expected demangled_size to return length including trailing null");
262 if (Log *log = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_DEMANGLE)) {
264 log->Printf("demangled itanium: %s -> \"%s\"", M, demangled_cstr);
266 log->Printf("demangled itanium: %s -> error: failed to demangle", M);
269 return demangled_cstr;
272 // Explicit demangling for scheduled requests during batch processing. This
273 // makes use of ItaniumPartialDemangler's rich demangle info
274 bool Mangled::DemangleWithRichManglingInfo(
275 RichManglingContext &context, SkipMangledNameFn *skip_mangled_name) {
276 // We need to generate and cache the demangled name.
277 static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
278 Timer scoped_timer(func_cat,
279 "Mangled::DemangleWithRichNameIndexInfo (m_mangled = %s)",
280 m_mangled.GetCString());
282 // Others are not meant to arrive here. ObjC names or C's main() for example
283 // have their names stored in m_demangled, while m_mangled is empty.
286 // Check whether or not we are interested in this name at all.
287 ManglingScheme scheme = cstring_mangling_scheme(m_mangled.GetCString());
288 if (skip_mangled_name && skip_mangled_name(m_mangled.GetStringRef(), scheme))
292 case eManglingSchemeNone:
293 // The current mangled_name_filter would allow llvm_unreachable here.
296 case eManglingSchemeItanium:
297 // We want the rich mangling info here, so we don't care whether or not
298 // there is a demangled string in the pool already.
299 if (context.FromItaniumName(m_mangled)) {
300 // If we got an info, we have a name. Copy to string pool and connect the
301 // counterparts to accelerate later access in GetDemangledName().
302 context.ParseFullName();
303 m_demangled.SetStringWithMangledCounterpart(context.GetBufferRef(),
307 m_demangled.SetCString("");
311 case eManglingSchemeMSVC: {
312 // We have no rich mangling for MSVC-mangled names yet, so first try to
313 // demangle it if necessary.
314 if (!m_demangled && !m_mangled.GetMangledCounterpart(m_demangled)) {
315 if (char *d = GetMSVCDemangledStr(m_mangled.GetCString())) {
316 // If we got an info, we have a name. Copy to string pool and connect
317 // the counterparts to accelerate later access in GetDemangledName().
318 m_demangled.SetStringWithMangledCounterpart(llvm::StringRef(d),
322 m_demangled.SetCString("");
326 if (m_demangled.IsEmpty()) {
327 // Cannot demangle it, so don't try parsing.
330 // Demangled successfully, we can try and parse it with
331 // CPlusPlusLanguage::MethodName.
332 return context.FromCxxMethodName(m_demangled);
336 llvm_unreachable("Fully covered switch above!");
339 // Generate the demangled name on demand using this accessor. Code in this
340 // class will need to use this accessor if it wishes to decode the demangled
341 // name. The result is cached and will be kept until a new string value is
342 // supplied to this object, or until the end of the object's lifetime.
344 Mangled::GetDemangledName(lldb::LanguageType language) const {
345 // Check to make sure we have a valid mangled name and that we haven't
346 // already decoded our mangled name.
347 if (m_mangled && m_demangled.IsNull()) {
348 // We need to generate and cache the demangled name.
349 static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
350 Timer scoped_timer(func_cat, "Mangled::GetDemangledName (m_mangled = %s)",
351 m_mangled.GetCString());
353 // Don't bother running anything that isn't mangled
354 const char *mangled_name = m_mangled.GetCString();
355 ManglingScheme mangling_scheme{cstring_mangling_scheme(mangled_name)};
356 if (mangling_scheme != eManglingSchemeNone &&
357 !m_mangled.GetMangledCounterpart(m_demangled)) {
358 // We didn't already mangle this name, demangle it and if all goes well
359 // add it to our map.
360 char *demangled_name = nullptr;
361 switch (mangling_scheme) {
362 case eManglingSchemeMSVC:
363 demangled_name = GetMSVCDemangledStr(mangled_name);
365 case eManglingSchemeItanium: {
366 demangled_name = GetItaniumDemangledStr(mangled_name);
369 case eManglingSchemeNone:
370 llvm_unreachable("eManglingSchemeNone was handled already");
372 if (demangled_name) {
373 m_demangled.SetStringWithMangledCounterpart(
374 llvm::StringRef(demangled_name), m_mangled);
375 free(demangled_name);
378 if (m_demangled.IsNull()) {
379 // Set the demangled string to the empty string to indicate we tried to
380 // parse it once and failed.
381 m_demangled.SetCString("");
389 Mangled::GetDisplayDemangledName(lldb::LanguageType language) const {
390 return GetDemangledName(language);
393 bool Mangled::NameMatches(const RegularExpression ®ex,
394 lldb::LanguageType language) const {
395 if (m_mangled && regex.Execute(m_mangled.AsCString()))
398 ConstString demangled = GetDemangledName(language);
399 return demangled && regex.Execute(demangled.AsCString());
402 // Get the demangled name if there is one, else return the mangled name.
403 ConstString Mangled::GetName(lldb::LanguageType language,
404 Mangled::NamePreference preference) const {
405 if (preference == ePreferMangled && m_mangled)
408 ConstString demangled = GetDemangledName(language);
410 if (preference == ePreferDemangledWithoutArguments) {
411 return get_demangled_name_without_arguments(m_mangled, demangled);
413 if (preference == ePreferDemangled) {
414 // Call the accessor to make sure we get a demangled name in case it hasn't
415 // been demangled yet...
423 // Dump a Mangled object to stream "s". We don't force our demangled name to be
424 // computed currently (we don't use the accessor).
425 void Mangled::Dump(Stream *s) const {
427 *s << ", mangled = " << m_mangled;
430 const char *demangled = m_demangled.AsCString();
431 s->Printf(", demangled = %s", demangled[0] ? demangled : "<error>");
435 // Dumps a debug version of this string with extra object and state information
437 void Mangled::DumpDebug(Stream *s) const {
438 s->Printf("%*p: Mangled mangled = ", static_cast<int>(sizeof(void *) * 2),
439 static_cast<const void *>(this));
440 m_mangled.DumpDebug(s);
441 s->Printf(", demangled = ");
442 m_demangled.DumpDebug(s);
445 // Return the size in byte that this object takes in memory. The size includes
446 // the size of the objects it owns, and not the strings that it references
447 // because they are shared strings.
448 size_t Mangled::MemorySize() const {
449 return m_mangled.MemorySize() + m_demangled.MemorySize();
452 // We "guess" the language because we can't determine a symbol's language from
453 // it's name. For example, a Pascal symbol can be mangled using the C++
454 // Itanium scheme, and defined in a compilation unit within the same module as
455 // other C++ units. In addition, different targets could have different ways
456 // of mangling names from a given language, likewise the compilation units
457 // within those targets.
458 lldb::LanguageType Mangled::GuessLanguage() const {
459 ConstString mangled = GetMangledName();
461 const char *mangled_name = mangled.GetCString();
462 if (CPlusPlusLanguage::IsCPPMangledName(mangled_name))
463 return lldb::eLanguageTypeC_plus_plus;
464 else if (ObjCLanguage::IsPossibleObjCMethodName(mangled_name))
465 return lldb::eLanguageTypeObjC;
467 // ObjC names aren't really mangled, so they won't necessarily be in the
468 // mangled name slot.
469 ConstString demangled_name = GetDemangledName(lldb::eLanguageTypeUnknown);
471 && ObjCLanguage::IsPossibleObjCMethodName(demangled_name.GetCString()))
472 return lldb::eLanguageTypeObjC;
475 return lldb::eLanguageTypeUnknown;
478 // Dump OBJ to the supplied stream S.
479 Stream &operator<<(Stream &s, const Mangled &obj) {
480 if (obj.GetMangledName())
481 s << "mangled = '" << obj.GetMangledName() << "'";
483 ConstString demangled =
484 obj.GetDemangledName(lldb::eLanguageTypeUnknown);
486 s << ", demangled = '" << demangled << '\'';
488 s << ", demangled = <error>";