1 //===-- DWARFASTParserClang.cpp -------------------------------------------===//
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 #include <cstdlib>
10 
11 #include "DWARFASTParserClang.h"
12 #include "DWARFDebugInfo.h"
13 #include "DWARFDeclContext.h"
14 #include "DWARFDefines.h"
15 #include "SymbolFileDWARF.h"
16 #include "SymbolFileDWARFDebugMap.h"
17 #include "SymbolFileDWARFDwo.h"
18 #include "UniqueDWARFASTType.h"
19 
20 #include "Plugins/ExpressionParser/Clang/ClangASTImporter.h"
21 #include "Plugins/ExpressionParser/Clang/ClangASTMetadata.h"
22 #include "Plugins/ExpressionParser/Clang/ClangUtil.h"
23 #include "Plugins/Language/ObjC/ObjCLanguage.h"
24 #include "lldb/Core/Module.h"
25 #include "lldb/Core/Value.h"
26 #include "lldb/Host/Host.h"
27 #include "lldb/Symbol/CompileUnit.h"
28 #include "lldb/Symbol/Function.h"
29 #include "lldb/Symbol/ObjectFile.h"
30 #include "lldb/Symbol/SymbolFile.h"
31 #include "lldb/Symbol/TypeList.h"
32 #include "lldb/Symbol/TypeMap.h"
33 #include "lldb/Target/Language.h"
34 #include "lldb/Utility/LLDBAssert.h"
35 #include "lldb/Utility/Log.h"
36 #include "lldb/Utility/StreamString.h"
37 
38 #include "llvm/Demangle/Demangle.h"
39 
40 #include "clang/AST/CXXInheritance.h"
41 #include "clang/AST/DeclCXX.h"
42 #include "clang/AST/DeclObjC.h"
43 #include "clang/AST/DeclTemplate.h"
44 
45 #include <map>
46 #include <memory>
47 #include <vector>
48 
49 //#define ENABLE_DEBUG_PRINTF // COMMENT OUT THIS LINE PRIOR TO CHECKIN
50 
51 #ifdef ENABLE_DEBUG_PRINTF
52 #include <cstdio>
53 #define DEBUG_PRINTF(fmt, ...) printf(fmt, __VA_ARGS__)
54 #else
55 #define DEBUG_PRINTF(fmt, ...)
56 #endif
57 
58 using namespace lldb;
59 using namespace lldb_private;
60 DWARFASTParserClang::DWARFASTParserClang(TypeSystemClang &ast)
61     : m_ast(ast), m_die_to_decl_ctx(), m_decl_ctx_to_die() {}
62 
63 DWARFASTParserClang::~DWARFASTParserClang() = default;
64 
65 static AccessType DW_ACCESS_to_AccessType(uint32_t dwarf_accessibility) {
66   switch (dwarf_accessibility) {
67   case DW_ACCESS_public:
68     return eAccessPublic;
69   case DW_ACCESS_private:
70     return eAccessPrivate;
71   case DW_ACCESS_protected:
72     return eAccessProtected;
73   default:
74     break;
75   }
76   return eAccessNone;
77 }
78 
79 static bool DeclKindIsCXXClass(clang::Decl::Kind decl_kind) {
80   switch (decl_kind) {
81   case clang::Decl::CXXRecord:
82   case clang::Decl::ClassTemplateSpecialization:
83     return true;
84   default:
85     break;
86   }
87   return false;
88 }
89 
90 
91 ClangASTImporter &DWARFASTParserClang::GetClangASTImporter() {
92   if (!m_clang_ast_importer_up) {
93     m_clang_ast_importer_up = std::make_unique<ClangASTImporter>();
94   }
95   return *m_clang_ast_importer_up;
96 }
97 
98 /// Detect a forward declaration that is nested in a DW_TAG_module.
99 static bool IsClangModuleFwdDecl(const DWARFDIE &Die) {
100   if (!Die.GetAttributeValueAsUnsigned(DW_AT_declaration, 0))
101     return false;
102   auto Parent = Die.GetParent();
103   while (Parent.IsValid()) {
104     if (Parent.Tag() == DW_TAG_module)
105       return true;
106     Parent = Parent.GetParent();
107   }
108   return false;
109 }
110 
111 static DWARFDIE GetContainingClangModuleDIE(const DWARFDIE &die) {
112   if (die.IsValid()) {
113     DWARFDIE top_module_die;
114     // Now make sure this DIE is scoped in a DW_TAG_module tag and return true
115     // if so
116     for (DWARFDIE parent = die.GetParent(); parent.IsValid();
117          parent = parent.GetParent()) {
118       const dw_tag_t tag = parent.Tag();
119       if (tag == DW_TAG_module)
120         top_module_die = parent;
121       else if (tag == DW_TAG_compile_unit || tag == DW_TAG_partial_unit)
122         break;
123     }
124 
125     return top_module_die;
126   }
127   return DWARFDIE();
128 }
129 
130 static lldb::ModuleSP GetContainingClangModule(const DWARFDIE &die) {
131   if (die.IsValid()) {
132     DWARFDIE clang_module_die = GetContainingClangModuleDIE(die);
133 
134     if (clang_module_die) {
135       const char *module_name = clang_module_die.GetName();
136       if (module_name)
137         return die.GetDWARF()->GetExternalModule(
138             lldb_private::ConstString(module_name));
139     }
140   }
141   return lldb::ModuleSP();
142 }
143 
144 TypeSP DWARFASTParserClang::ParseTypeFromClangModule(const SymbolContext &sc,
145                                                      const DWARFDIE &die,
146                                                      Log *log) {
147   ModuleSP clang_module_sp = GetContainingClangModule(die);
148   if (!clang_module_sp)
149     return TypeSP();
150 
151   // If this type comes from a Clang module, recursively look in the
152   // DWARF section of the .pcm file in the module cache. Clang
153   // generates DWO skeleton units as breadcrumbs to find them.
154   llvm::SmallVector<CompilerContext, 4> decl_context;
155   die.GetDeclContext(decl_context);
156   TypeMap pcm_types;
157 
158   // The type in the Clang module must have the same language as the current CU.
159   LanguageSet languages;
160   languages.Insert(SymbolFileDWARF::GetLanguageFamily(*die.GetCU()));
161   llvm::DenseSet<SymbolFile *> searched_symbol_files;
162   clang_module_sp->GetSymbolFile()->FindTypes(decl_context, languages,
163                                               searched_symbol_files, pcm_types);
164   if (pcm_types.Empty()) {
165     // Since this type is defined in one of the Clang modules imported
166     // by this symbol file, search all of them. Instead of calling
167     // sym_file->FindTypes(), which would return this again, go straight
168     // to the imported modules.
169     auto &sym_file = die.GetCU()->GetSymbolFileDWARF();
170 
171     // Well-formed clang modules never form cycles; guard against corrupted
172     // ones by inserting the current file.
173     searched_symbol_files.insert(&sym_file);
174     sym_file.ForEachExternalModule(
175         *sc.comp_unit, searched_symbol_files, [&](Module &module) {
176           module.GetSymbolFile()->FindTypes(decl_context, languages,
177                                             searched_symbol_files, pcm_types);
178           return pcm_types.GetSize();
179         });
180   }
181 
182   if (!pcm_types.GetSize())
183     return TypeSP();
184 
185   // We found a real definition for this type in the Clang module, so lets use
186   // it and cache the fact that we found a complete type for this die.
187   TypeSP pcm_type_sp = pcm_types.GetTypeAtIndex(0);
188   if (!pcm_type_sp)
189     return TypeSP();
190 
191   lldb_private::CompilerType pcm_type = pcm_type_sp->GetForwardCompilerType();
192   lldb_private::CompilerType type =
193       GetClangASTImporter().CopyType(m_ast, pcm_type);
194 
195   if (!type)
196     return TypeSP();
197 
198   // Under normal operation pcm_type is a shallow forward declaration
199   // that gets completed later. This is necessary to support cyclic
200   // data structures. If, however, pcm_type is already complete (for
201   // example, because it was loaded for a different target before),
202   // the definition needs to be imported right away, too.
203   // Type::ResolveClangType() effectively ignores the ResolveState
204   // inside type_sp and only looks at IsDefined(), so it never calls
205   // ClangASTImporter::ASTImporterDelegate::ImportDefinitionTo(),
206   // which does extra work for Objective-C classes. This would result
207   // in only the forward declaration to be visible.
208   if (pcm_type.IsDefined())
209     GetClangASTImporter().RequireCompleteType(ClangUtil::GetQualType(type));
210 
211   SymbolFileDWARF *dwarf = die.GetDWARF();
212   TypeSP type_sp(new Type(die.GetID(), dwarf, pcm_type_sp->GetName(),
213                           pcm_type_sp->GetByteSize(nullptr), nullptr,
214                           LLDB_INVALID_UID, Type::eEncodingInvalid,
215                           &pcm_type_sp->GetDeclaration(), type,
216                           Type::ResolveState::Forward,
217                           TypePayloadClang(GetOwningClangModule(die))));
218 
219   dwarf->GetTypeList().Insert(type_sp);
220   dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
221   clang::TagDecl *tag_decl = TypeSystemClang::GetAsTagDecl(type);
222   if (tag_decl) {
223     LinkDeclContextToDIE(tag_decl, die);
224   } else {
225     clang::DeclContext *defn_decl_ctx = GetCachedClangDeclContextForDIE(die);
226     if (defn_decl_ctx)
227       LinkDeclContextToDIE(defn_decl_ctx, die);
228   }
229 
230   return type_sp;
231 }
232 
233 static void ForcefullyCompleteType(CompilerType type) {
234   bool started = TypeSystemClang::StartTagDeclarationDefinition(type);
235   lldbassert(started && "Unable to start a class type definition.");
236   TypeSystemClang::CompleteTagDeclarationDefinition(type);
237   const clang::TagDecl *td = ClangUtil::GetAsTagDecl(type);
238   auto &ts = llvm::cast<TypeSystemClang>(*type.GetTypeSystem());
239   ts.GetMetadata(td)->SetIsForcefullyCompleted();
240 }
241 
242 /// Complete a type from debug info, or mark it as forcefully completed if
243 /// there is no definition of the type in the current Module. Call this function
244 /// in contexts where the usual C++ rules require a type to be complete (base
245 /// class, member, etc.).
246 static void RequireCompleteType(CompilerType type) {
247   // Technically, enums can be incomplete too, but we don't handle those as they
248   // are emitted even under -flimit-debug-info.
249   if (!TypeSystemClang::IsCXXClassType(type))
250     return;
251 
252   if (type.GetCompleteType())
253     return;
254 
255   // No complete definition in this module.  Mark the class as complete to
256   // satisfy local ast invariants, but make a note of the fact that
257   // it is not _really_ complete so we can later search for a definition in a
258   // different module.
259   // Since we provide layout assistance, layouts of types containing this class
260   // will be correct even if we  are not able to find the definition elsewhere.
261   ForcefullyCompleteType(type);
262 }
263 
264 /// This function serves a similar purpose as RequireCompleteType above, but it
265 /// avoids completing the type if it is not immediately necessary. It only
266 /// ensures we _can_ complete the type later.
267 static void PrepareContextToReceiveMembers(TypeSystemClang &ast,
268                                            ClangASTImporter &ast_importer,
269                                            clang::DeclContext *decl_ctx,
270                                            DWARFDIE die,
271                                            const char *type_name_cstr) {
272   auto *tag_decl_ctx = clang::dyn_cast<clang::TagDecl>(decl_ctx);
273   if (!tag_decl_ctx)
274     return; // Non-tag context are always ready.
275 
276   // We have already completed the type, or we have found its definition and are
277   // ready to complete it later (cf. ParseStructureLikeDIE).
278   if (tag_decl_ctx->isCompleteDefinition() || tag_decl_ctx->isBeingDefined())
279     return;
280 
281   // We reach this point of the tag was present in the debug info as a
282   // declaration only. If it was imported from another AST context (in the
283   // gmodules case), we can complete the type by doing a full import.
284 
285   // If this type was not imported from an external AST, there's nothing to do.
286   CompilerType type = ast.GetTypeForDecl(tag_decl_ctx);
287   if (type && ast_importer.CanImport(type)) {
288     auto qual_type = ClangUtil::GetQualType(type);
289     if (ast_importer.RequireCompleteType(qual_type))
290       return;
291     die.GetDWARF()->GetObjectFile()->GetModule()->ReportError(
292         "Unable to complete the Decl context for DIE '%s' at offset "
293         "0x%8.8x.\nPlease file a bug report.",
294         type_name_cstr ? type_name_cstr : "", die.GetOffset());
295   }
296 
297   // We don't have a type definition and/or the import failed. We must
298   // forcefully complete the type to avoid crashes.
299   ForcefullyCompleteType(type);
300 }
301 
302 ParsedDWARFTypeAttributes::ParsedDWARFTypeAttributes(const DWARFDIE &die) {
303   DWARFAttributes attributes;
304   size_t num_attributes = die.GetAttributes(attributes);
305   for (size_t i = 0; i < num_attributes; ++i) {
306     dw_attr_t attr = attributes.AttributeAtIndex(i);
307     DWARFFormValue form_value;
308     if (!attributes.ExtractFormValueAtIndex(i, form_value))
309       continue;
310     switch (attr) {
311     case DW_AT_abstract_origin:
312       abstract_origin = form_value;
313       break;
314 
315     case DW_AT_accessibility:
316       accessibility = DW_ACCESS_to_AccessType(form_value.Unsigned());
317       break;
318 
319     case DW_AT_artificial:
320       is_artificial = form_value.Boolean();
321       break;
322 
323     case DW_AT_bit_stride:
324       bit_stride = form_value.Unsigned();
325       break;
326 
327     case DW_AT_byte_size:
328       byte_size = form_value.Unsigned();
329       break;
330 
331     case DW_AT_byte_stride:
332       byte_stride = form_value.Unsigned();
333       break;
334 
335     case DW_AT_calling_convention:
336       calling_convention = form_value.Unsigned();
337       break;
338 
339     case DW_AT_containing_type:
340       containing_type = form_value;
341       break;
342 
343     case DW_AT_decl_file:
344       // die.GetCU() can differ if DW_AT_specification uses DW_FORM_ref_addr.
345       decl.SetFile(
346           attributes.CompileUnitAtIndex(i)->GetFile(form_value.Unsigned()));
347       break;
348     case DW_AT_decl_line:
349       decl.SetLine(form_value.Unsigned());
350       break;
351     case DW_AT_decl_column:
352       decl.SetColumn(form_value.Unsigned());
353       break;
354 
355     case DW_AT_declaration:
356       is_forward_declaration = form_value.Boolean();
357       break;
358 
359     case DW_AT_encoding:
360       encoding = form_value.Unsigned();
361       break;
362 
363     case DW_AT_enum_class:
364       is_scoped_enum = form_value.Boolean();
365       break;
366 
367     case DW_AT_explicit:
368       is_explicit = form_value.Boolean();
369       break;
370 
371     case DW_AT_external:
372       if (form_value.Unsigned())
373         storage = clang::SC_Extern;
374       break;
375 
376     case DW_AT_inline:
377       is_inline = form_value.Boolean();
378       break;
379 
380     case DW_AT_linkage_name:
381     case DW_AT_MIPS_linkage_name:
382       mangled_name = form_value.AsCString();
383       break;
384 
385     case DW_AT_name:
386       name.SetCString(form_value.AsCString());
387       break;
388 
389     case DW_AT_object_pointer:
390       object_pointer = form_value.Reference();
391       break;
392 
393     case DW_AT_signature:
394       signature = form_value;
395       break;
396 
397     case DW_AT_specification:
398       specification = form_value;
399       break;
400 
401     case DW_AT_type:
402       type = form_value;
403       break;
404 
405     case DW_AT_virtuality:
406       is_virtual = form_value.Boolean();
407       break;
408 
409     case DW_AT_APPLE_objc_complete_type:
410       is_complete_objc_class = form_value.Signed();
411       break;
412 
413     case DW_AT_APPLE_objc_direct:
414       is_objc_direct_call = true;
415       break;
416 
417     case DW_AT_APPLE_runtime_class:
418       class_language = (LanguageType)form_value.Signed();
419       break;
420 
421     case DW_AT_GNU_vector:
422       is_vector = form_value.Boolean();
423       break;
424     case DW_AT_export_symbols:
425       exports_symbols = form_value.Boolean();
426       break;
427     }
428   }
429 }
430 
431 static std::string GetUnitName(const DWARFDIE &die) {
432   if (DWARFUnit *unit = die.GetCU())
433     return unit->GetAbsolutePath().GetPath();
434   return "<missing DWARF unit path>";
435 }
436 
437 TypeSP DWARFASTParserClang::ParseTypeFromDWARF(const SymbolContext &sc,
438                                                const DWARFDIE &die,
439                                                bool *type_is_new_ptr) {
440   if (type_is_new_ptr)
441     *type_is_new_ptr = false;
442 
443   if (!die)
444     return nullptr;
445 
446   Log *log(LogChannelDWARF::GetLogIfAny(DWARF_LOG_TYPE_COMPLETION |
447                                         DWARF_LOG_LOOKUPS));
448 
449   SymbolFileDWARF *dwarf = die.GetDWARF();
450   if (log) {
451     DWARFDIE context_die;
452     clang::DeclContext *context =
453         GetClangDeclContextContainingDIE(die, &context_die);
454 
455     dwarf->GetObjectFile()->GetModule()->LogMessage(
456         log,
457         "DWARFASTParserClang::ParseTypeFromDWARF "
458         "(die = 0x%8.8x, decl_ctx = %p (die 0x%8.8x)) %s name = '%s')",
459         die.GetOffset(), static_cast<void *>(context), context_die.GetOffset(),
460         die.GetTagAsCString(), die.GetName());
461   }
462 
463   Type *type_ptr = dwarf->GetDIEToType().lookup(die.GetDIE());
464   if (type_ptr == DIE_IS_BEING_PARSED)
465     return nullptr;
466   if (type_ptr)
467     return type_ptr->shared_from_this();
468   // Set a bit that lets us know that we are currently parsing this
469   dwarf->GetDIEToType()[die.GetDIE()] = DIE_IS_BEING_PARSED;
470 
471   ParsedDWARFTypeAttributes attrs(die);
472 
473   if (DWARFDIE signature_die = attrs.signature.Reference()) {
474     if (TypeSP type_sp =
475             ParseTypeFromDWARF(sc, signature_die, type_is_new_ptr)) {
476       dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
477       if (clang::DeclContext *decl_ctx =
478               GetCachedClangDeclContextForDIE(signature_die))
479         LinkDeclContextToDIE(decl_ctx, die);
480       return type_sp;
481     }
482     return nullptr;
483   }
484 
485   if (type_is_new_ptr)
486     *type_is_new_ptr = true;
487 
488   const dw_tag_t tag = die.Tag();
489 
490   TypeSP type_sp;
491 
492   switch (tag) {
493   case DW_TAG_typedef:
494   case DW_TAG_base_type:
495   case DW_TAG_pointer_type:
496   case DW_TAG_reference_type:
497   case DW_TAG_rvalue_reference_type:
498   case DW_TAG_const_type:
499   case DW_TAG_restrict_type:
500   case DW_TAG_volatile_type:
501   case DW_TAG_atomic_type:
502   case DW_TAG_unspecified_type: {
503     type_sp = ParseTypeModifier(sc, die, attrs);
504     break;
505   }
506 
507   case DW_TAG_structure_type:
508   case DW_TAG_union_type:
509   case DW_TAG_class_type: {
510     type_sp = ParseStructureLikeDIE(sc, die, attrs);
511     break;
512   }
513 
514   case DW_TAG_enumeration_type: {
515     type_sp = ParseEnum(sc, die, attrs);
516     break;
517   }
518 
519   case DW_TAG_inlined_subroutine:
520   case DW_TAG_subprogram:
521   case DW_TAG_subroutine_type: {
522     type_sp = ParseSubroutine(die, attrs);
523     break;
524   }
525   case DW_TAG_array_type: {
526     type_sp = ParseArrayType(die, attrs);
527     break;
528   }
529   case DW_TAG_ptr_to_member_type: {
530     type_sp = ParsePointerToMemberType(die, attrs);
531     break;
532   }
533   default:
534     dwarf->GetObjectFile()->GetModule()->ReportError(
535         "{0x%8.8x}: unhandled type tag 0x%4.4x (%s), please file a bug and "
536         "attach the file at the start of this error message",
537         die.GetOffset(), tag, DW_TAG_value_to_name(tag));
538     break;
539   }
540 
541   // TODO: We should consider making the switch above exhaustive to simplify
542   // control flow in ParseTypeFromDWARF. Then, we could simply replace this
543   // return statement with a call to llvm_unreachable.
544   return UpdateSymbolContextScopeForType(sc, die, type_sp);
545 }
546 
547 lldb::TypeSP
548 DWARFASTParserClang::ParseTypeModifier(const SymbolContext &sc,
549                                        const DWARFDIE &die,
550                                        ParsedDWARFTypeAttributes &attrs) {
551   Log *log(LogChannelDWARF::GetLogIfAny(DWARF_LOG_TYPE_COMPLETION |
552                                         DWARF_LOG_LOOKUPS));
553   SymbolFileDWARF *dwarf = die.GetDWARF();
554   const dw_tag_t tag = die.Tag();
555   LanguageType cu_language = SymbolFileDWARF::GetLanguage(*die.GetCU());
556   Type::ResolveState resolve_state = Type::ResolveState::Unresolved;
557   Type::EncodingDataType encoding_data_type = Type::eEncodingIsUID;
558   TypeSP type_sp;
559   CompilerType clang_type;
560 
561   if (tag == DW_TAG_typedef) {
562     // DeclContext will be populated when the clang type is materialized in
563     // Type::ResolveCompilerType.
564     PrepareContextToReceiveMembers(
565         m_ast, GetClangASTImporter(),
566         GetClangDeclContextContainingDIE(die, nullptr), die,
567         attrs.name.GetCString());
568 
569     if (attrs.type.IsValid()) {
570       // Try to parse a typedef from the (DWARF embedded in the) Clang
571       // module file first as modules can contain typedef'ed
572       // structures that have no names like:
573       //
574       //  typedef struct { int a; } Foo;
575       //
576       // In this case we will have a structure with no name and a
577       // typedef named "Foo" that points to this unnamed
578       // structure. The name in the typedef is the only identifier for
579       // the struct, so always try to get typedefs from Clang modules
580       // if possible.
581       //
582       // The type_sp returned will be empty if the typedef doesn't
583       // exist in a module file, so it is cheap to call this function
584       // just to check.
585       //
586       // If we don't do this we end up creating a TypeSP that says
587       // this is a typedef to type 0x123 (the DW_AT_type value would
588       // be 0x123 in the DW_TAG_typedef), and this is the unnamed
589       // structure type. We will have a hard time tracking down an
590       // unnammed structure type in the module debug info, so we make
591       // sure we don't get into this situation by always resolving
592       // typedefs from the module.
593       const DWARFDIE encoding_die = attrs.type.Reference();
594 
595       // First make sure that the die that this is typedef'ed to _is_
596       // just a declaration (DW_AT_declaration == 1), not a full
597       // definition since template types can't be represented in
598       // modules since only concrete instances of templates are ever
599       // emitted and modules won't contain those
600       if (encoding_die &&
601           encoding_die.GetAttributeValueAsUnsigned(DW_AT_declaration, 0) == 1) {
602         type_sp = ParseTypeFromClangModule(sc, die, log);
603         if (type_sp)
604           return type_sp;
605       }
606     }
607   }
608 
609   DEBUG_PRINTF("0x%8.8" PRIx64 ": %s (\"%s\") type => 0x%8.8lx\n", die.GetID(),
610                DW_TAG_value_to_name(tag), type_name_cstr,
611                encoding_uid.Reference());
612 
613   switch (tag) {
614   default:
615     break;
616 
617   case DW_TAG_unspecified_type:
618     if (attrs.name == "nullptr_t" || attrs.name == "decltype(nullptr)") {
619       resolve_state = Type::ResolveState::Full;
620       clang_type = m_ast.GetBasicType(eBasicTypeNullPtr);
621       break;
622     }
623     // Fall through to base type below in case we can handle the type
624     // there...
625     LLVM_FALLTHROUGH;
626 
627   case DW_TAG_base_type:
628     resolve_state = Type::ResolveState::Full;
629     clang_type = m_ast.GetBuiltinTypeForDWARFEncodingAndBitSize(
630         attrs.name.GetStringRef(), attrs.encoding,
631         attrs.byte_size.getValueOr(0) * 8);
632     break;
633 
634   case DW_TAG_pointer_type:
635     encoding_data_type = Type::eEncodingIsPointerUID;
636     break;
637   case DW_TAG_reference_type:
638     encoding_data_type = Type::eEncodingIsLValueReferenceUID;
639     break;
640   case DW_TAG_rvalue_reference_type:
641     encoding_data_type = Type::eEncodingIsRValueReferenceUID;
642     break;
643   case DW_TAG_typedef:
644     encoding_data_type = Type::eEncodingIsTypedefUID;
645     break;
646   case DW_TAG_const_type:
647     encoding_data_type = Type::eEncodingIsConstUID;
648     break;
649   case DW_TAG_restrict_type:
650     encoding_data_type = Type::eEncodingIsRestrictUID;
651     break;
652   case DW_TAG_volatile_type:
653     encoding_data_type = Type::eEncodingIsVolatileUID;
654     break;
655   case DW_TAG_atomic_type:
656     encoding_data_type = Type::eEncodingIsAtomicUID;
657     break;
658   }
659 
660   if (!clang_type && (encoding_data_type == Type::eEncodingIsPointerUID ||
661                       encoding_data_type == Type::eEncodingIsTypedefUID)) {
662     if (tag == DW_TAG_pointer_type) {
663       DWARFDIE target_die = die.GetReferencedDIE(DW_AT_type);
664 
665       if (target_die.GetAttributeValueAsUnsigned(DW_AT_APPLE_block, 0)) {
666         // Blocks have a __FuncPtr inside them which is a pointer to a
667         // function of the proper type.
668 
669         for (DWARFDIE child_die : target_die.children()) {
670           if (!strcmp(child_die.GetAttributeValueAsString(DW_AT_name, ""),
671                       "__FuncPtr")) {
672             DWARFDIE function_pointer_type =
673                 child_die.GetReferencedDIE(DW_AT_type);
674 
675             if (function_pointer_type) {
676               DWARFDIE function_type =
677                   function_pointer_type.GetReferencedDIE(DW_AT_type);
678 
679               bool function_type_is_new_pointer;
680               TypeSP lldb_function_type_sp = ParseTypeFromDWARF(
681                   sc, function_type, &function_type_is_new_pointer);
682 
683               if (lldb_function_type_sp) {
684                 clang_type = m_ast.CreateBlockPointerType(
685                     lldb_function_type_sp->GetForwardCompilerType());
686                 encoding_data_type = Type::eEncodingIsUID;
687                 attrs.type.Clear();
688                 resolve_state = Type::ResolveState::Full;
689               }
690             }
691 
692             break;
693           }
694         }
695       }
696     }
697 
698     if (cu_language == eLanguageTypeObjC ||
699         cu_language == eLanguageTypeObjC_plus_plus) {
700       if (attrs.name) {
701         if (attrs.name == "id") {
702           if (log)
703             dwarf->GetObjectFile()->GetModule()->LogMessage(
704                 log,
705                 "SymbolFileDWARF::ParseType (die = 0x%8.8x) %s '%s' "
706                 "is Objective-C 'id' built-in type.",
707                 die.GetOffset(), die.GetTagAsCString(), die.GetName());
708           clang_type = m_ast.GetBasicType(eBasicTypeObjCID);
709           encoding_data_type = Type::eEncodingIsUID;
710           attrs.type.Clear();
711           resolve_state = Type::ResolveState::Full;
712         } else if (attrs.name == "Class") {
713           if (log)
714             dwarf->GetObjectFile()->GetModule()->LogMessage(
715                 log,
716                 "SymbolFileDWARF::ParseType (die = 0x%8.8x) %s '%s' "
717                 "is Objective-C 'Class' built-in type.",
718                 die.GetOffset(), die.GetTagAsCString(), die.GetName());
719           clang_type = m_ast.GetBasicType(eBasicTypeObjCClass);
720           encoding_data_type = Type::eEncodingIsUID;
721           attrs.type.Clear();
722           resolve_state = Type::ResolveState::Full;
723         } else if (attrs.name == "SEL") {
724           if (log)
725             dwarf->GetObjectFile()->GetModule()->LogMessage(
726                 log,
727                 "SymbolFileDWARF::ParseType (die = 0x%8.8x) %s '%s' "
728                 "is Objective-C 'selector' built-in type.",
729                 die.GetOffset(), die.GetTagAsCString(), die.GetName());
730           clang_type = m_ast.GetBasicType(eBasicTypeObjCSel);
731           encoding_data_type = Type::eEncodingIsUID;
732           attrs.type.Clear();
733           resolve_state = Type::ResolveState::Full;
734         }
735       } else if (encoding_data_type == Type::eEncodingIsPointerUID &&
736                  attrs.type.IsValid()) {
737         // Clang sometimes erroneously emits id as objc_object*.  In that
738         // case we fix up the type to "id".
739 
740         const DWARFDIE encoding_die = attrs.type.Reference();
741 
742         if (encoding_die && encoding_die.Tag() == DW_TAG_structure_type) {
743           llvm::StringRef struct_name = encoding_die.GetName();
744           if (struct_name == "objc_object") {
745             if (log)
746               dwarf->GetObjectFile()->GetModule()->LogMessage(
747                   log,
748                   "SymbolFileDWARF::ParseType (die = 0x%8.8x) %s "
749                   "'%s' is 'objc_object*', which we overrode to "
750                   "'id'.",
751                   die.GetOffset(), die.GetTagAsCString(), die.GetName());
752             clang_type = m_ast.GetBasicType(eBasicTypeObjCID);
753             encoding_data_type = Type::eEncodingIsUID;
754             attrs.type.Clear();
755             resolve_state = Type::ResolveState::Full;
756           }
757         }
758       }
759     }
760   }
761 
762   type_sp = std::make_shared<Type>(
763       die.GetID(), dwarf, attrs.name, attrs.byte_size, nullptr,
764       dwarf->GetUID(attrs.type.Reference()), encoding_data_type, &attrs.decl,
765       clang_type, resolve_state, TypePayloadClang(GetOwningClangModule(die)));
766 
767   dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
768   return type_sp;
769 }
770 
771 TypeSP DWARFASTParserClang::ParseEnum(const SymbolContext &sc,
772                                       const DWARFDIE &die,
773                                       ParsedDWARFTypeAttributes &attrs) {
774   Log *log(LogChannelDWARF::GetLogIfAny(DWARF_LOG_TYPE_COMPLETION |
775                                         DWARF_LOG_LOOKUPS));
776   SymbolFileDWARF *dwarf = die.GetDWARF();
777   const dw_tag_t tag = die.Tag();
778   TypeSP type_sp;
779 
780   if (attrs.is_forward_declaration) {
781     type_sp = ParseTypeFromClangModule(sc, die, log);
782     if (type_sp)
783       return type_sp;
784 
785     DWARFDeclContext die_decl_ctx = SymbolFileDWARF::GetDWARFDeclContext(die);
786 
787     type_sp = dwarf->FindDefinitionTypeForDWARFDeclContext(die_decl_ctx);
788 
789     if (!type_sp) {
790       SymbolFileDWARFDebugMap *debug_map_symfile = dwarf->GetDebugMapSymfile();
791       if (debug_map_symfile) {
792         // We weren't able to find a full declaration in this DWARF,
793         // see if we have a declaration anywhere else...
794         type_sp = debug_map_symfile->FindDefinitionTypeForDWARFDeclContext(
795             die_decl_ctx);
796       }
797     }
798 
799     if (type_sp) {
800       if (log) {
801         dwarf->GetObjectFile()->GetModule()->LogMessage(
802             log,
803             "SymbolFileDWARF(%p) - 0x%8.8x: %s type \"%s\" is a "
804             "forward declaration, complete type is 0x%8.8" PRIx64,
805             static_cast<void *>(this), die.GetOffset(),
806             DW_TAG_value_to_name(tag), attrs.name.GetCString(),
807             type_sp->GetID());
808       }
809 
810       // We found a real definition for this type elsewhere so lets use
811       // it and cache the fact that we found a complete type for this
812       // die
813       dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
814       clang::DeclContext *defn_decl_ctx =
815           GetCachedClangDeclContextForDIE(dwarf->GetDIE(type_sp->GetID()));
816       if (defn_decl_ctx)
817         LinkDeclContextToDIE(defn_decl_ctx, die);
818       return type_sp;
819     }
820   }
821   DEBUG_PRINTF("0x%8.8" PRIx64 ": %s (\"%s\")\n", die.GetID(),
822                DW_TAG_value_to_name(tag), type_name_cstr);
823 
824   CompilerType enumerator_clang_type;
825   CompilerType clang_type;
826   clang_type.SetCompilerType(
827       &m_ast, dwarf->GetForwardDeclDieToClangType().lookup(die.GetDIE()));
828   if (!clang_type) {
829     if (attrs.type.IsValid()) {
830       Type *enumerator_type =
831           dwarf->ResolveTypeUID(attrs.type.Reference(), true);
832       if (enumerator_type)
833         enumerator_clang_type = enumerator_type->GetFullCompilerType();
834     }
835 
836     if (!enumerator_clang_type) {
837       if (attrs.byte_size) {
838         enumerator_clang_type = m_ast.GetBuiltinTypeForDWARFEncodingAndBitSize(
839             "", DW_ATE_signed, *attrs.byte_size * 8);
840       } else {
841         enumerator_clang_type = m_ast.GetBasicType(eBasicTypeInt);
842       }
843     }
844 
845     clang_type = m_ast.CreateEnumerationType(
846         attrs.name.GetCString(), GetClangDeclContextContainingDIE(die, nullptr),
847         GetOwningClangModule(die), attrs.decl, enumerator_clang_type,
848         attrs.is_scoped_enum);
849   } else {
850     enumerator_clang_type = m_ast.GetEnumerationIntegerType(clang_type);
851   }
852 
853   LinkDeclContextToDIE(TypeSystemClang::GetDeclContextForType(clang_type), die);
854 
855   type_sp = std::make_shared<Type>(
856       die.GetID(), dwarf, attrs.name, attrs.byte_size, nullptr,
857       dwarf->GetUID(attrs.type.Reference()), Type::eEncodingIsUID, &attrs.decl,
858       clang_type, Type::ResolveState::Forward,
859       TypePayloadClang(GetOwningClangModule(die)));
860 
861   if (TypeSystemClang::StartTagDeclarationDefinition(clang_type)) {
862     if (die.HasChildren()) {
863       bool is_signed = false;
864       enumerator_clang_type.IsIntegerType(is_signed);
865       ParseChildEnumerators(clang_type, is_signed,
866                             type_sp->GetByteSize(nullptr).getValueOr(0), die);
867     }
868     TypeSystemClang::CompleteTagDeclarationDefinition(clang_type);
869   } else {
870     dwarf->GetObjectFile()->GetModule()->ReportError(
871         "DWARF DIE at 0x%8.8x named \"%s\" was not able to start its "
872         "definition.\nPlease file a bug and attach the file at the "
873         "start of this error message",
874         die.GetOffset(), attrs.name.GetCString());
875   }
876   return type_sp;
877 }
878 
879 TypeSP DWARFASTParserClang::ParseSubroutine(const DWARFDIE &die,
880                            ParsedDWARFTypeAttributes &attrs) {
881   Log *log(LogChannelDWARF::GetLogIfAny(DWARF_LOG_TYPE_COMPLETION |
882                                         DWARF_LOG_LOOKUPS));
883 
884   SymbolFileDWARF *dwarf = die.GetDWARF();
885   const dw_tag_t tag = die.Tag();
886 
887   bool is_variadic = false;
888   bool is_static = false;
889   bool has_template_params = false;
890 
891   unsigned type_quals = 0;
892 
893   std::string object_pointer_name;
894   if (attrs.object_pointer) {
895     const char *object_pointer_name_cstr = attrs.object_pointer.GetName();
896     if (object_pointer_name_cstr)
897       object_pointer_name = object_pointer_name_cstr;
898   }
899 
900   DEBUG_PRINTF("0x%8.8" PRIx64 ": %s (\"%s\")\n", die.GetID(),
901                DW_TAG_value_to_name(tag), type_name_cstr);
902 
903   CompilerType return_clang_type;
904   Type *func_type = NULL;
905 
906   if (attrs.type.IsValid())
907     func_type = dwarf->ResolveTypeUID(attrs.type.Reference(), true);
908 
909   if (func_type)
910     return_clang_type = func_type->GetForwardCompilerType();
911   else
912     return_clang_type = m_ast.GetBasicType(eBasicTypeVoid);
913 
914   std::vector<CompilerType> function_param_types;
915   std::vector<clang::ParmVarDecl *> function_param_decls;
916 
917   // Parse the function children for the parameters
918 
919   DWARFDIE decl_ctx_die;
920   clang::DeclContext *containing_decl_ctx =
921       GetClangDeclContextContainingDIE(die, &decl_ctx_die);
922   const clang::Decl::Kind containing_decl_kind =
923       containing_decl_ctx->getDeclKind();
924 
925   bool is_cxx_method = DeclKindIsCXXClass(containing_decl_kind);
926   // Start off static. This will be set to false in
927   // ParseChildParameters(...) if we find a "this" parameters as the
928   // first parameter
929   if (is_cxx_method) {
930     is_static = true;
931   }
932 
933   if (die.HasChildren()) {
934     bool skip_artificial = true;
935     ParseChildParameters(containing_decl_ctx, die, skip_artificial, is_static,
936                          is_variadic, has_template_params,
937                          function_param_types, function_param_decls,
938                          type_quals);
939   }
940 
941   bool ignore_containing_context = false;
942   // Check for templatized class member functions. If we had any
943   // DW_TAG_template_type_parameter or DW_TAG_template_value_parameter
944   // the DW_TAG_subprogram DIE, then we can't let this become a method in
945   // a class. Why? Because templatized functions are only emitted if one
946   // of the templatized methods is used in the current compile unit and
947   // we will end up with classes that may or may not include these member
948   // functions and this means one class won't match another class
949   // definition and it affects our ability to use a class in the clang
950   // expression parser. So for the greater good, we currently must not
951   // allow any template member functions in a class definition.
952   if (is_cxx_method && has_template_params) {
953     ignore_containing_context = true;
954     is_cxx_method = false;
955   }
956 
957   // clang_type will get the function prototype clang type after this
958   // call
959   CompilerType clang_type = m_ast.CreateFunctionType(
960       return_clang_type, function_param_types.data(),
961       function_param_types.size(), is_variadic, type_quals);
962 
963   if (attrs.name) {
964     bool type_handled = false;
965     if (tag == DW_TAG_subprogram || tag == DW_TAG_inlined_subroutine) {
966       ObjCLanguage::MethodName objc_method(attrs.name.GetStringRef(), true);
967       if (objc_method.IsValid(true)) {
968         CompilerType class_opaque_type;
969         ConstString class_name(objc_method.GetClassName());
970         if (class_name) {
971           TypeSP complete_objc_class_type_sp(
972               dwarf->FindCompleteObjCDefinitionTypeForDIE(DWARFDIE(),
973                                                           class_name, false));
974 
975           if (complete_objc_class_type_sp) {
976             CompilerType type_clang_forward_type =
977                 complete_objc_class_type_sp->GetForwardCompilerType();
978             if (TypeSystemClang::IsObjCObjectOrInterfaceType(
979                     type_clang_forward_type))
980               class_opaque_type = type_clang_forward_type;
981           }
982         }
983 
984         if (class_opaque_type) {
985           // If accessibility isn't set to anything valid, assume public
986           // for now...
987           if (attrs.accessibility == eAccessNone)
988             attrs.accessibility = eAccessPublic;
989 
990           clang::ObjCMethodDecl *objc_method_decl =
991               m_ast.AddMethodToObjCObjectType(
992                   class_opaque_type, attrs.name.GetCString(), clang_type,
993                   attrs.accessibility, attrs.is_artificial, is_variadic,
994                   attrs.is_objc_direct_call);
995           type_handled = objc_method_decl != NULL;
996           if (type_handled) {
997             LinkDeclContextToDIE(objc_method_decl, die);
998             m_ast.SetMetadataAsUserID(objc_method_decl, die.GetID());
999           } else {
1000             dwarf->GetObjectFile()->GetModule()->ReportError(
1001                 "{0x%8.8x}: invalid Objective-C method 0x%4.4x (%s), "
1002                 "please file a bug and attach the file at the start of "
1003                 "this error message",
1004                 die.GetOffset(), tag, DW_TAG_value_to_name(tag));
1005           }
1006         }
1007       } else if (is_cxx_method) {
1008         // Look at the parent of this DIE and see if is is a class or
1009         // struct and see if this is actually a C++ method
1010         Type *class_type = dwarf->ResolveType(decl_ctx_die);
1011         if (class_type) {
1012           bool alternate_defn = false;
1013           if (class_type->GetID() != decl_ctx_die.GetID() ||
1014               IsClangModuleFwdDecl(decl_ctx_die)) {
1015             alternate_defn = true;
1016 
1017             // We uniqued the parent class of this function to another
1018             // class so we now need to associate all dies under
1019             // "decl_ctx_die" to DIEs in the DIE for "class_type"...
1020             DWARFDIE class_type_die = dwarf->GetDIE(class_type->GetID());
1021 
1022             if (class_type_die) {
1023               std::vector<DWARFDIE> failures;
1024 
1025               CopyUniqueClassMethodTypes(decl_ctx_die, class_type_die,
1026                                          class_type, failures);
1027 
1028               // FIXME do something with these failures that's
1029               // smarter than just dropping them on the ground.
1030               // Unfortunately classes don't like having stuff added
1031               // to them after their definitions are complete...
1032 
1033               Type *type_ptr = dwarf->GetDIEToType()[die.GetDIE()];
1034               if (type_ptr && type_ptr != DIE_IS_BEING_PARSED) {
1035                 return type_ptr->shared_from_this();
1036               }
1037             }
1038           }
1039 
1040           if (attrs.specification.IsValid()) {
1041             // We have a specification which we are going to base our
1042             // function prototype off of, so we need this type to be
1043             // completed so that the m_die_to_decl_ctx for the method in
1044             // the specification has a valid clang decl context.
1045             class_type->GetForwardCompilerType();
1046             // If we have a specification, then the function type should
1047             // have been made with the specification and not with this
1048             // die.
1049             DWARFDIE spec_die = attrs.specification.Reference();
1050             clang::DeclContext *spec_clang_decl_ctx =
1051                 GetClangDeclContextForDIE(spec_die);
1052             if (spec_clang_decl_ctx) {
1053               LinkDeclContextToDIE(spec_clang_decl_ctx, die);
1054             } else {
1055               dwarf->GetObjectFile()->GetModule()->ReportWarning(
1056                   "0x%8.8" PRIx64 ": DW_AT_specification(0x%8.8x"
1057                   ") has no decl\n",
1058                   die.GetID(), spec_die.GetOffset());
1059             }
1060             type_handled = true;
1061           } else if (attrs.abstract_origin.IsValid()) {
1062             // We have a specification which we are going to base our
1063             // function prototype off of, so we need this type to be
1064             // completed so that the m_die_to_decl_ctx for the method in
1065             // the abstract origin has a valid clang decl context.
1066             class_type->GetForwardCompilerType();
1067 
1068             DWARFDIE abs_die = attrs.abstract_origin.Reference();
1069             clang::DeclContext *abs_clang_decl_ctx =
1070                 GetClangDeclContextForDIE(abs_die);
1071             if (abs_clang_decl_ctx) {
1072               LinkDeclContextToDIE(abs_clang_decl_ctx, die);
1073             } else {
1074               dwarf->GetObjectFile()->GetModule()->ReportWarning(
1075                   "0x%8.8" PRIx64 ": DW_AT_abstract_origin(0x%8.8x"
1076                   ") has no decl\n",
1077                   die.GetID(), abs_die.GetOffset());
1078             }
1079             type_handled = true;
1080           } else {
1081             CompilerType class_opaque_type =
1082                 class_type->GetForwardCompilerType();
1083             if (TypeSystemClang::IsCXXClassType(class_opaque_type)) {
1084               if (class_opaque_type.IsBeingDefined() || alternate_defn) {
1085                 if (!is_static && !die.HasChildren()) {
1086                   // We have a C++ member function with no children (this
1087                   // pointer!) and clang will get mad if we try and make
1088                   // a function that isn't well formed in the DWARF, so
1089                   // we will just skip it...
1090                   type_handled = true;
1091                 } else {
1092                   bool add_method = true;
1093                   if (alternate_defn) {
1094                     // If an alternate definition for the class exists,
1095                     // then add the method only if an equivalent is not
1096                     // already present.
1097                     clang::CXXRecordDecl *record_decl =
1098                         m_ast.GetAsCXXRecordDecl(
1099                             class_opaque_type.GetOpaqueQualType());
1100                     if (record_decl) {
1101                       for (auto method_iter = record_decl->method_begin();
1102                            method_iter != record_decl->method_end();
1103                            method_iter++) {
1104                         clang::CXXMethodDecl *method_decl = *method_iter;
1105                         if (method_decl->getNameInfo().getAsString() ==
1106                             attrs.name.GetStringRef()) {
1107                           if (method_decl->getType() ==
1108                               ClangUtil::GetQualType(clang_type)) {
1109                             add_method = false;
1110                             LinkDeclContextToDIE(method_decl, die);
1111                             type_handled = true;
1112 
1113                             break;
1114                           }
1115                         }
1116                       }
1117                     }
1118                   }
1119 
1120                   if (add_method) {
1121                     llvm::PrettyStackTraceFormat stack_trace(
1122                         "SymbolFileDWARF::ParseType() is adding a method "
1123                         "%s to class %s in DIE 0x%8.8" PRIx64 " from %s",
1124                         attrs.name.GetCString(),
1125                         class_type->GetName().GetCString(), die.GetID(),
1126                         dwarf->GetObjectFile()
1127                             ->GetFileSpec()
1128                             .GetPath()
1129                             .c_str());
1130 
1131                     const bool is_attr_used = false;
1132                     // Neither GCC 4.2 nor clang++ currently set a valid
1133                     // accessibility in the DWARF for C++ methods...
1134                     // Default to public for now...
1135                     if (attrs.accessibility == eAccessNone)
1136                       attrs.accessibility = eAccessPublic;
1137 
1138                     clang::CXXMethodDecl *cxx_method_decl =
1139                         m_ast.AddMethodToCXXRecordType(
1140                             class_opaque_type.GetOpaqueQualType(),
1141                             attrs.name.GetCString(), attrs.mangled_name,
1142                             clang_type, attrs.accessibility, attrs.is_virtual,
1143                             is_static, attrs.is_inline, attrs.is_explicit,
1144                             is_attr_used, attrs.is_artificial);
1145 
1146                     type_handled = cxx_method_decl != NULL;
1147                     // Artificial methods are always handled even when we
1148                     // don't create a new declaration for them.
1149                     type_handled |= attrs.is_artificial;
1150 
1151                     if (cxx_method_decl) {
1152                       LinkDeclContextToDIE(cxx_method_decl, die);
1153 
1154                       ClangASTMetadata metadata;
1155                       metadata.SetUserID(die.GetID());
1156 
1157                       if (!object_pointer_name.empty()) {
1158                         metadata.SetObjectPtrName(
1159                             object_pointer_name.c_str());
1160                         LLDB_LOGF(log,
1161                                   "Setting object pointer name: %s on method "
1162                                   "object %p.\n",
1163                                   object_pointer_name.c_str(),
1164                                   static_cast<void *>(cxx_method_decl));
1165                       }
1166                       m_ast.SetMetadata(cxx_method_decl, metadata);
1167                     } else {
1168                       ignore_containing_context = true;
1169                     }
1170                   }
1171                 }
1172               } else {
1173                 // We were asked to parse the type for a method in a
1174                 // class, yet the class hasn't been asked to complete
1175                 // itself through the clang::ExternalASTSource protocol,
1176                 // so we need to just have the class complete itself and
1177                 // do things the right way, then our
1178                 // DIE should then have an entry in the
1179                 // dwarf->GetDIEToType() map. First
1180                 // we need to modify the dwarf->GetDIEToType() so it
1181                 // doesn't think we are trying to parse this DIE
1182                 // anymore...
1183                 dwarf->GetDIEToType()[die.GetDIE()] = NULL;
1184 
1185                 // Now we get the full type to force our class type to
1186                 // complete itself using the clang::ExternalASTSource
1187                 // protocol which will parse all base classes and all
1188                 // methods (including the method for this DIE).
1189                 class_type->GetFullCompilerType();
1190 
1191                 // The type for this DIE should have been filled in the
1192                 // function call above
1193                 Type *type_ptr = dwarf->GetDIEToType()[die.GetDIE()];
1194                 if (type_ptr && type_ptr != DIE_IS_BEING_PARSED) {
1195                   return type_ptr->shared_from_this();
1196                 }
1197 
1198                 // FIXME This is fixing some even uglier behavior but we
1199                 // really need to
1200                 // uniq the methods of each class as well as the class
1201                 // itself. <rdar://problem/11240464>
1202                 type_handled = true;
1203               }
1204             }
1205           }
1206         }
1207       }
1208     }
1209 
1210     if (!type_handled) {
1211       clang::FunctionDecl *function_decl = nullptr;
1212       clang::FunctionDecl *template_function_decl = nullptr;
1213 
1214       if (attrs.abstract_origin.IsValid()) {
1215         DWARFDIE abs_die = attrs.abstract_origin.Reference();
1216 
1217         if (dwarf->ResolveType(abs_die)) {
1218           function_decl = llvm::dyn_cast_or_null<clang::FunctionDecl>(
1219               GetCachedClangDeclContextForDIE(abs_die));
1220 
1221           if (function_decl) {
1222             LinkDeclContextToDIE(function_decl, die);
1223           }
1224         }
1225       }
1226 
1227       if (!function_decl) {
1228         char *name_buf = nullptr;
1229         llvm::StringRef name = attrs.name.GetStringRef();
1230 
1231         // We currently generate function templates with template parameters in
1232         // their name. In order to get closer to the AST that clang generates
1233         // we want to strip these from the name when creating the AST.
1234         if (attrs.mangled_name) {
1235           llvm::ItaniumPartialDemangler D;
1236           if (!D.partialDemangle(attrs.mangled_name)) {
1237             name_buf = D.getFunctionBaseName(nullptr, nullptr);
1238             name = name_buf;
1239           }
1240         }
1241 
1242         // We just have a function that isn't part of a class
1243         function_decl = m_ast.CreateFunctionDeclaration(
1244             ignore_containing_context ? m_ast.GetTranslationUnitDecl()
1245                                       : containing_decl_ctx,
1246             GetOwningClangModule(die), name, clang_type, attrs.storage,
1247             attrs.is_inline);
1248         std::free(name_buf);
1249 
1250         if (has_template_params) {
1251           TypeSystemClang::TemplateParameterInfos template_param_infos;
1252           ParseTemplateParameterInfos(die, template_param_infos);
1253           template_function_decl = m_ast.CreateFunctionDeclaration(
1254               ignore_containing_context ? m_ast.GetTranslationUnitDecl()
1255                                         : containing_decl_ctx,
1256               GetOwningClangModule(die), attrs.name.GetStringRef(), clang_type,
1257               attrs.storage, attrs.is_inline);
1258           clang::FunctionTemplateDecl *func_template_decl =
1259               m_ast.CreateFunctionTemplateDecl(
1260                   containing_decl_ctx, GetOwningClangModule(die),
1261                   template_function_decl, template_param_infos);
1262           m_ast.CreateFunctionTemplateSpecializationInfo(
1263               template_function_decl, func_template_decl, template_param_infos);
1264         }
1265 
1266         lldbassert(function_decl);
1267 
1268         if (function_decl) {
1269           LinkDeclContextToDIE(function_decl, die);
1270 
1271           if (!function_param_decls.empty()) {
1272             m_ast.SetFunctionParameters(function_decl, function_param_decls);
1273             if (template_function_decl)
1274               m_ast.SetFunctionParameters(template_function_decl,
1275                                           function_param_decls);
1276           }
1277 
1278           ClangASTMetadata metadata;
1279           metadata.SetUserID(die.GetID());
1280 
1281           if (!object_pointer_name.empty()) {
1282             metadata.SetObjectPtrName(object_pointer_name.c_str());
1283             LLDB_LOGF(log,
1284                       "Setting object pointer name: %s on function "
1285                       "object %p.",
1286                       object_pointer_name.c_str(),
1287                       static_cast<void *>(function_decl));
1288           }
1289           m_ast.SetMetadata(function_decl, metadata);
1290         }
1291       }
1292     }
1293   }
1294   return std::make_shared<Type>(
1295       die.GetID(), dwarf, attrs.name, llvm::None, nullptr, LLDB_INVALID_UID,
1296       Type::eEncodingIsUID, &attrs.decl, clang_type, Type::ResolveState::Full);
1297 }
1298 
1299 TypeSP DWARFASTParserClang::ParseArrayType(const DWARFDIE &die,
1300                                            ParsedDWARFTypeAttributes &attrs) {
1301   SymbolFileDWARF *dwarf = die.GetDWARF();
1302 
1303   DEBUG_PRINTF("0x%8.8" PRIx64 ": %s (\"%s\")\n", die.GetID(),
1304                DW_TAG_value_to_name(tag), type_name_cstr);
1305 
1306   DWARFDIE type_die = attrs.type.Reference();
1307   Type *element_type = dwarf->ResolveTypeUID(type_die, true);
1308 
1309   if (!element_type)
1310     return nullptr;
1311 
1312   llvm::Optional<SymbolFile::ArrayInfo> array_info = ParseChildArrayInfo(die);
1313   if (array_info) {
1314     attrs.byte_stride = array_info->byte_stride;
1315     attrs.bit_stride = array_info->bit_stride;
1316   }
1317   if (attrs.byte_stride == 0 && attrs.bit_stride == 0)
1318     attrs.byte_stride = element_type->GetByteSize(nullptr).getValueOr(0);
1319   CompilerType array_element_type = element_type->GetForwardCompilerType();
1320   RequireCompleteType(array_element_type);
1321 
1322   uint64_t array_element_bit_stride =
1323       attrs.byte_stride * 8 + attrs.bit_stride;
1324   CompilerType clang_type;
1325   if (array_info && array_info->element_orders.size() > 0) {
1326     uint64_t num_elements = 0;
1327     auto end = array_info->element_orders.rend();
1328     for (auto pos = array_info->element_orders.rbegin(); pos != end; ++pos) {
1329       num_elements = *pos;
1330       clang_type = m_ast.CreateArrayType(array_element_type, num_elements,
1331                                          attrs.is_vector);
1332       array_element_type = clang_type;
1333       array_element_bit_stride = num_elements
1334                                      ? array_element_bit_stride * num_elements
1335                                      : array_element_bit_stride;
1336     }
1337   } else {
1338     clang_type =
1339         m_ast.CreateArrayType(array_element_type, 0, attrs.is_vector);
1340   }
1341   ConstString empty_name;
1342   TypeSP type_sp = std::make_shared<Type>(
1343       die.GetID(), dwarf, empty_name, array_element_bit_stride / 8, nullptr,
1344       dwarf->GetUID(type_die), Type::eEncodingIsUID, &attrs.decl, clang_type,
1345       Type::ResolveState::Full);
1346   type_sp->SetEncodingType(element_type);
1347   const clang::Type *type = ClangUtil::GetQualType(clang_type).getTypePtr();
1348   m_ast.SetMetadataAsUserID(type, die.GetID());
1349   return type_sp;
1350 }
1351 
1352 TypeSP DWARFASTParserClang::ParsePointerToMemberType(
1353     const DWARFDIE &die, const ParsedDWARFTypeAttributes &attrs) {
1354   SymbolFileDWARF *dwarf = die.GetDWARF();
1355   Type *pointee_type = dwarf->ResolveTypeUID(attrs.type.Reference(), true);
1356   Type *class_type =
1357       dwarf->ResolveTypeUID(attrs.containing_type.Reference(), true);
1358 
1359   CompilerType pointee_clang_type = pointee_type->GetForwardCompilerType();
1360   CompilerType class_clang_type = class_type->GetForwardCompilerType();
1361 
1362   CompilerType clang_type = TypeSystemClang::CreateMemberPointerType(
1363       class_clang_type, pointee_clang_type);
1364 
1365   if (llvm::Optional<uint64_t> clang_type_size =
1366           clang_type.GetByteSize(nullptr)) {
1367     return std::make_shared<Type>(die.GetID(), dwarf, attrs.name,
1368                                   *clang_type_size, nullptr, LLDB_INVALID_UID,
1369                                   Type::eEncodingIsUID, nullptr, clang_type,
1370                                   Type::ResolveState::Forward);
1371   }
1372   return nullptr;
1373 }
1374 
1375 TypeSP DWARFASTParserClang::UpdateSymbolContextScopeForType(
1376     const SymbolContext &sc, const DWARFDIE &die, TypeSP type_sp) {
1377   if (!type_sp)
1378     return type_sp;
1379 
1380   SymbolFileDWARF *dwarf = die.GetDWARF();
1381   TypeList &type_list = dwarf->GetTypeList();
1382   DWARFDIE sc_parent_die = SymbolFileDWARF::GetParentSymbolContextDIE(die);
1383   dw_tag_t sc_parent_tag = sc_parent_die.Tag();
1384 
1385   SymbolContextScope *symbol_context_scope = nullptr;
1386   if (sc_parent_tag == DW_TAG_compile_unit ||
1387       sc_parent_tag == DW_TAG_partial_unit) {
1388     symbol_context_scope = sc.comp_unit;
1389   } else if (sc.function != nullptr && sc_parent_die) {
1390     symbol_context_scope =
1391         sc.function->GetBlock(true).FindBlockByID(sc_parent_die.GetID());
1392     if (symbol_context_scope == nullptr)
1393       symbol_context_scope = sc.function;
1394   } else {
1395     symbol_context_scope = sc.module_sp.get();
1396   }
1397 
1398   if (symbol_context_scope != nullptr)
1399     type_sp->SetSymbolContextScope(symbol_context_scope);
1400 
1401   // We are ready to put this type into the uniqued list up at the module
1402   // level.
1403   type_list.Insert(type_sp);
1404 
1405   dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
1406   return type_sp;
1407 }
1408 
1409 TypeSP
1410 DWARFASTParserClang::ParseStructureLikeDIE(const SymbolContext &sc,
1411                                            const DWARFDIE &die,
1412                                            ParsedDWARFTypeAttributes &attrs) {
1413   TypeSP type_sp;
1414   CompilerType clang_type;
1415   const dw_tag_t tag = die.Tag();
1416   SymbolFileDWARF *dwarf = die.GetDWARF();
1417   LanguageType cu_language = SymbolFileDWARF::GetLanguage(*die.GetCU());
1418   Log *log = LogChannelDWARF::GetLogIfAll(DWARF_LOG_TYPE_COMPLETION |
1419                                           DWARF_LOG_LOOKUPS);
1420 
1421   // UniqueDWARFASTType is large, so don't create a local variables on the
1422   // stack, put it on the heap. This function is often called recursively and
1423   // clang isn't good at sharing the stack space for variables in different
1424   // blocks.
1425   auto unique_ast_entry_up = std::make_unique<UniqueDWARFASTType>();
1426 
1427   ConstString unique_typename(attrs.name);
1428   Declaration unique_decl(attrs.decl);
1429 
1430   if (attrs.name) {
1431     if (Language::LanguageIsCPlusPlus(cu_language)) {
1432       // For C++, we rely solely upon the one definition rule that says
1433       // only one thing can exist at a given decl context. We ignore the
1434       // file and line that things are declared on.
1435       std::string qualified_name;
1436       if (die.GetQualifiedName(qualified_name))
1437         unique_typename = ConstString(qualified_name);
1438       unique_decl.Clear();
1439     }
1440 
1441     if (dwarf->GetUniqueDWARFASTTypeMap().Find(
1442             unique_typename, die, unique_decl, attrs.byte_size.getValueOr(-1),
1443             *unique_ast_entry_up)) {
1444       type_sp = unique_ast_entry_up->m_type_sp;
1445       if (type_sp) {
1446         dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
1447         LinkDeclContextToDIE(
1448             GetCachedClangDeclContextForDIE(unique_ast_entry_up->m_die), die);
1449         return type_sp;
1450       }
1451     }
1452   }
1453 
1454   DEBUG_PRINTF("0x%8.8" PRIx64 ": %s (\"%s\")\n", die.GetID(),
1455                DW_TAG_value_to_name(tag), type_name_cstr);
1456 
1457   int tag_decl_kind = -1;
1458   AccessType default_accessibility = eAccessNone;
1459   if (tag == DW_TAG_structure_type) {
1460     tag_decl_kind = clang::TTK_Struct;
1461     default_accessibility = eAccessPublic;
1462   } else if (tag == DW_TAG_union_type) {
1463     tag_decl_kind = clang::TTK_Union;
1464     default_accessibility = eAccessPublic;
1465   } else if (tag == DW_TAG_class_type) {
1466     tag_decl_kind = clang::TTK_Class;
1467     default_accessibility = eAccessPrivate;
1468   }
1469 
1470   if (attrs.byte_size && *attrs.byte_size == 0 && attrs.name &&
1471       !die.HasChildren() && cu_language == eLanguageTypeObjC) {
1472     // Work around an issue with clang at the moment where forward
1473     // declarations for objective C classes are emitted as:
1474     //  DW_TAG_structure_type [2]
1475     //  DW_AT_name( "ForwardObjcClass" )
1476     //  DW_AT_byte_size( 0x00 )
1477     //  DW_AT_decl_file( "..." )
1478     //  DW_AT_decl_line( 1 )
1479     //
1480     // Note that there is no DW_AT_declaration and there are no children,
1481     // and the byte size is zero.
1482     attrs.is_forward_declaration = true;
1483   }
1484 
1485   if (attrs.class_language == eLanguageTypeObjC ||
1486       attrs.class_language == eLanguageTypeObjC_plus_plus) {
1487     if (!attrs.is_complete_objc_class &&
1488         die.Supports_DW_AT_APPLE_objc_complete_type()) {
1489       // We have a valid eSymbolTypeObjCClass class symbol whose name
1490       // matches the current objective C class that we are trying to find
1491       // and this DIE isn't the complete definition (we checked
1492       // is_complete_objc_class above and know it is false), so the real
1493       // definition is in here somewhere
1494       type_sp =
1495           dwarf->FindCompleteObjCDefinitionTypeForDIE(die, attrs.name, true);
1496 
1497       if (!type_sp) {
1498         SymbolFileDWARFDebugMap *debug_map_symfile =
1499             dwarf->GetDebugMapSymfile();
1500         if (debug_map_symfile) {
1501           // We weren't able to find a full declaration in this DWARF,
1502           // see if we have a declaration anywhere else...
1503           type_sp = debug_map_symfile->FindCompleteObjCDefinitionTypeForDIE(
1504               die, attrs.name, true);
1505         }
1506       }
1507 
1508       if (type_sp) {
1509         if (log) {
1510           dwarf->GetObjectFile()->GetModule()->LogMessage(
1511               log,
1512               "SymbolFileDWARF(%p) - 0x%8.8x: %s type \"%s\" is an "
1513               "incomplete objc type, complete type is 0x%8.8" PRIx64,
1514               static_cast<void *>(this), die.GetOffset(),
1515               DW_TAG_value_to_name(tag), attrs.name.GetCString(),
1516               type_sp->GetID());
1517         }
1518 
1519         // We found a real definition for this type elsewhere so lets use
1520         // it and cache the fact that we found a complete type for this
1521         // die
1522         dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
1523         return type_sp;
1524       }
1525     }
1526   }
1527 
1528   if (attrs.is_forward_declaration) {
1529     // We have a forward declaration to a type and we need to try and
1530     // find a full declaration. We look in the current type index just in
1531     // case we have a forward declaration followed by an actual
1532     // declarations in the DWARF. If this fails, we need to look
1533     // elsewhere...
1534     if (log) {
1535       dwarf->GetObjectFile()->GetModule()->LogMessage(
1536           log,
1537           "SymbolFileDWARF(%p) - 0x%8.8x: %s type \"%s\" is a "
1538           "forward declaration, trying to find complete type",
1539           static_cast<void *>(this), die.GetOffset(), DW_TAG_value_to_name(tag),
1540           attrs.name.GetCString());
1541     }
1542 
1543     // See if the type comes from a Clang module and if so, track down
1544     // that type.
1545     type_sp = ParseTypeFromClangModule(sc, die, log);
1546     if (type_sp)
1547       return type_sp;
1548 
1549     DWARFDeclContext die_decl_ctx = SymbolFileDWARF::GetDWARFDeclContext(die);
1550 
1551     // type_sp = FindDefinitionTypeForDIE (dwarf_cu, die,
1552     // type_name_const_str);
1553     type_sp = dwarf->FindDefinitionTypeForDWARFDeclContext(die_decl_ctx);
1554 
1555     if (!type_sp) {
1556       SymbolFileDWARFDebugMap *debug_map_symfile = dwarf->GetDebugMapSymfile();
1557       if (debug_map_symfile) {
1558         // We weren't able to find a full declaration in this DWARF, see
1559         // if we have a declaration anywhere else...
1560         type_sp = debug_map_symfile->FindDefinitionTypeForDWARFDeclContext(
1561             die_decl_ctx);
1562       }
1563     }
1564 
1565     if (type_sp) {
1566       if (log) {
1567         dwarf->GetObjectFile()->GetModule()->LogMessage(
1568             log,
1569             "SymbolFileDWARF(%p) - 0x%8.8x: %s type \"%s\" is a "
1570             "forward declaration, complete type is 0x%8.8" PRIx64,
1571             static_cast<void *>(this), die.GetOffset(),
1572             DW_TAG_value_to_name(tag), attrs.name.GetCString(),
1573             type_sp->GetID());
1574       }
1575 
1576       // We found a real definition for this type elsewhere so lets use
1577       // it and cache the fact that we found a complete type for this die
1578       dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
1579       clang::DeclContext *defn_decl_ctx =
1580           GetCachedClangDeclContextForDIE(dwarf->GetDIE(type_sp->GetID()));
1581       if (defn_decl_ctx)
1582         LinkDeclContextToDIE(defn_decl_ctx, die);
1583       return type_sp;
1584     }
1585   }
1586   assert(tag_decl_kind != -1);
1587   (void)tag_decl_kind;
1588   bool clang_type_was_created = false;
1589   clang_type.SetCompilerType(
1590       &m_ast, dwarf->GetForwardDeclDieToClangType().lookup(die.GetDIE()));
1591   if (!clang_type) {
1592     clang::DeclContext *decl_ctx =
1593         GetClangDeclContextContainingDIE(die, nullptr);
1594 
1595     PrepareContextToReceiveMembers(m_ast, GetClangASTImporter(), decl_ctx, die,
1596                                    attrs.name.GetCString());
1597 
1598     if (attrs.accessibility == eAccessNone && decl_ctx) {
1599       // Check the decl context that contains this class/struct/union. If
1600       // it is a class we must give it an accessibility.
1601       const clang::Decl::Kind containing_decl_kind = decl_ctx->getDeclKind();
1602       if (DeclKindIsCXXClass(containing_decl_kind))
1603         attrs.accessibility = default_accessibility;
1604     }
1605 
1606     ClangASTMetadata metadata;
1607     metadata.SetUserID(die.GetID());
1608     metadata.SetIsDynamicCXXType(dwarf->ClassOrStructIsVirtual(die));
1609 
1610     if (attrs.name.GetStringRef().contains('<')) {
1611       TypeSystemClang::TemplateParameterInfos template_param_infos;
1612       if (ParseTemplateParameterInfos(die, template_param_infos)) {
1613         clang::ClassTemplateDecl *class_template_decl =
1614             m_ast.ParseClassTemplateDecl(
1615                 decl_ctx, GetOwningClangModule(die), attrs.accessibility,
1616                 attrs.name.GetCString(), tag_decl_kind, template_param_infos);
1617         if (!class_template_decl) {
1618           if (log) {
1619             dwarf->GetObjectFile()->GetModule()->LogMessage(
1620                 log,
1621                 "SymbolFileDWARF(%p) - 0x%8.8x: %s type \"%s\" "
1622                 "clang::ClassTemplateDecl failed to return a decl.",
1623                 static_cast<void *>(this), die.GetOffset(),
1624                 DW_TAG_value_to_name(tag), attrs.name.GetCString());
1625           }
1626           return TypeSP();
1627         }
1628 
1629         clang::ClassTemplateSpecializationDecl *class_specialization_decl =
1630             m_ast.CreateClassTemplateSpecializationDecl(
1631                 decl_ctx, GetOwningClangModule(die), class_template_decl,
1632                 tag_decl_kind, template_param_infos);
1633         clang_type = m_ast.CreateClassTemplateSpecializationType(
1634             class_specialization_decl);
1635         clang_type_was_created = true;
1636 
1637         m_ast.SetMetadata(class_template_decl, metadata);
1638         m_ast.SetMetadata(class_specialization_decl, metadata);
1639       }
1640     }
1641 
1642     if (!clang_type_was_created) {
1643       clang_type_was_created = true;
1644       clang_type = m_ast.CreateRecordType(
1645           decl_ctx, GetOwningClangModule(die), attrs.accessibility,
1646           attrs.name.GetCString(), tag_decl_kind, attrs.class_language,
1647           &metadata, attrs.exports_symbols);
1648     }
1649   }
1650 
1651   // Store a forward declaration to this class type in case any
1652   // parameters in any class methods need it for the clang types for
1653   // function prototypes.
1654   LinkDeclContextToDIE(m_ast.GetDeclContextForType(clang_type), die);
1655   type_sp = std::make_shared<Type>(
1656       die.GetID(), dwarf, attrs.name, attrs.byte_size, nullptr,
1657       LLDB_INVALID_UID, Type::eEncodingIsUID, &attrs.decl, clang_type,
1658       Type::ResolveState::Forward,
1659       TypePayloadClang(OptionalClangModuleID(), attrs.is_complete_objc_class));
1660 
1661   // Add our type to the unique type map so we don't end up creating many
1662   // copies of the same type over and over in the ASTContext for our
1663   // module
1664   unique_ast_entry_up->m_type_sp = type_sp;
1665   unique_ast_entry_up->m_die = die;
1666   unique_ast_entry_up->m_declaration = unique_decl;
1667   unique_ast_entry_up->m_byte_size = attrs.byte_size.getValueOr(0);
1668   dwarf->GetUniqueDWARFASTTypeMap().Insert(unique_typename,
1669                                            *unique_ast_entry_up);
1670 
1671   if (!attrs.is_forward_declaration) {
1672     // Always start the definition for a class type so that if the class
1673     // has child classes or types that require the class to be created
1674     // for use as their decl contexts the class will be ready to accept
1675     // these child definitions.
1676     if (!die.HasChildren()) {
1677       // No children for this struct/union/class, lets finish it
1678       if (TypeSystemClang::StartTagDeclarationDefinition(clang_type)) {
1679         TypeSystemClang::CompleteTagDeclarationDefinition(clang_type);
1680       } else {
1681         dwarf->GetObjectFile()->GetModule()->ReportError(
1682             "DWARF DIE at 0x%8.8x named \"%s\" was not able to start its "
1683             "definition.\nPlease file a bug and attach the file at the "
1684             "start of this error message",
1685             die.GetOffset(), attrs.name.GetCString());
1686       }
1687 
1688       // If the byte size of the record is specified then overwrite the size
1689       // that would be computed by Clang. This is only needed as LLDB's
1690       // TypeSystemClang is always in C++ mode, but some compilers such as
1691       // GCC and Clang give empty structs a size of 0 in C mode (in contrast to
1692       // the size of 1 for empty structs that would be computed in C++ mode).
1693       if (attrs.byte_size) {
1694         clang::RecordDecl *record_decl =
1695             TypeSystemClang::GetAsRecordDecl(clang_type);
1696         if (record_decl) {
1697           ClangASTImporter::LayoutInfo layout;
1698           layout.bit_size = *attrs.byte_size * 8;
1699           GetClangASTImporter().SetRecordLayout(record_decl, layout);
1700         }
1701       }
1702     } else if (clang_type_was_created) {
1703       // Start the definition if the class is not objective C since the
1704       // underlying decls respond to isCompleteDefinition(). Objective
1705       // C decls don't respond to isCompleteDefinition() so we can't
1706       // start the declaration definition right away. For C++
1707       // class/union/structs we want to start the definition in case the
1708       // class is needed as the declaration context for a contained class
1709       // or type without the need to complete that type..
1710 
1711       if (attrs.class_language != eLanguageTypeObjC &&
1712           attrs.class_language != eLanguageTypeObjC_plus_plus)
1713         TypeSystemClang::StartTagDeclarationDefinition(clang_type);
1714 
1715       // Leave this as a forward declaration until we need to know the
1716       // details of the type. lldb_private::Type will automatically call
1717       // the SymbolFile virtual function
1718       // "SymbolFileDWARF::CompleteType(Type *)" When the definition
1719       // needs to be defined.
1720       assert(!dwarf->GetForwardDeclClangTypeToDie().count(
1721                  ClangUtil::RemoveFastQualifiers(clang_type)
1722                      .GetOpaqueQualType()) &&
1723              "Type already in the forward declaration map!");
1724       // Can't assume m_ast.GetSymbolFile() is actually a
1725       // SymbolFileDWARF, it can be a SymbolFileDWARFDebugMap for Apple
1726       // binaries.
1727       dwarf->GetForwardDeclDieToClangType()[die.GetDIE()] =
1728           clang_type.GetOpaqueQualType();
1729       dwarf->GetForwardDeclClangTypeToDie().try_emplace(
1730           ClangUtil::RemoveFastQualifiers(clang_type).GetOpaqueQualType(),
1731           *die.GetDIERef());
1732       m_ast.SetHasExternalStorage(clang_type.GetOpaqueQualType(), true);
1733     }
1734   }
1735 
1736   // If we made a clang type, set the trivial abi if applicable: We only
1737   // do this for pass by value - which implies the Trivial ABI. There
1738   // isn't a way to assert that something that would normally be pass by
1739   // value is pass by reference, so we ignore that attribute if set.
1740   if (attrs.calling_convention == llvm::dwarf::DW_CC_pass_by_value) {
1741     clang::CXXRecordDecl *record_decl =
1742         m_ast.GetAsCXXRecordDecl(clang_type.GetOpaqueQualType());
1743     if (record_decl && record_decl->getDefinition()) {
1744       record_decl->setHasTrivialSpecialMemberForCall();
1745     }
1746   }
1747 
1748   if (attrs.calling_convention == llvm::dwarf::DW_CC_pass_by_reference) {
1749     clang::CXXRecordDecl *record_decl =
1750         m_ast.GetAsCXXRecordDecl(clang_type.GetOpaqueQualType());
1751     if (record_decl)
1752       record_decl->setArgPassingRestrictions(
1753           clang::RecordDecl::APK_CannotPassInRegs);
1754   }
1755   return type_sp;
1756 }
1757 
1758 // DWARF parsing functions
1759 
1760 class DWARFASTParserClang::DelayedAddObjCClassProperty {
1761 public:
1762   DelayedAddObjCClassProperty(
1763       const CompilerType &class_opaque_type, const char *property_name,
1764       const CompilerType &property_opaque_type, // The property type is only
1765                                                 // required if you don't have an
1766                                                 // ivar decl
1767       clang::ObjCIvarDecl *ivar_decl, const char *property_setter_name,
1768       const char *property_getter_name, uint32_t property_attributes,
1769       const ClangASTMetadata *metadata)
1770       : m_class_opaque_type(class_opaque_type), m_property_name(property_name),
1771         m_property_opaque_type(property_opaque_type), m_ivar_decl(ivar_decl),
1772         m_property_setter_name(property_setter_name),
1773         m_property_getter_name(property_getter_name),
1774         m_property_attributes(property_attributes) {
1775     if (metadata != nullptr) {
1776       m_metadata_up = std::make_unique<ClangASTMetadata>();
1777       *m_metadata_up = *metadata;
1778     }
1779   }
1780 
1781   DelayedAddObjCClassProperty(const DelayedAddObjCClassProperty &rhs) {
1782     *this = rhs;
1783   }
1784 
1785   DelayedAddObjCClassProperty &
1786   operator=(const DelayedAddObjCClassProperty &rhs) {
1787     m_class_opaque_type = rhs.m_class_opaque_type;
1788     m_property_name = rhs.m_property_name;
1789     m_property_opaque_type = rhs.m_property_opaque_type;
1790     m_ivar_decl = rhs.m_ivar_decl;
1791     m_property_setter_name = rhs.m_property_setter_name;
1792     m_property_getter_name = rhs.m_property_getter_name;
1793     m_property_attributes = rhs.m_property_attributes;
1794 
1795     if (rhs.m_metadata_up) {
1796       m_metadata_up = std::make_unique<ClangASTMetadata>();
1797       *m_metadata_up = *rhs.m_metadata_up;
1798     }
1799     return *this;
1800   }
1801 
1802   bool Finalize() {
1803     return TypeSystemClang::AddObjCClassProperty(
1804         m_class_opaque_type, m_property_name, m_property_opaque_type,
1805         m_ivar_decl, m_property_setter_name, m_property_getter_name,
1806         m_property_attributes, m_metadata_up.get());
1807   }
1808 
1809 private:
1810   CompilerType m_class_opaque_type;
1811   const char *m_property_name;
1812   CompilerType m_property_opaque_type;
1813   clang::ObjCIvarDecl *m_ivar_decl;
1814   const char *m_property_setter_name;
1815   const char *m_property_getter_name;
1816   uint32_t m_property_attributes;
1817   std::unique_ptr<ClangASTMetadata> m_metadata_up;
1818 };
1819 
1820 bool DWARFASTParserClang::ParseTemplateDIE(
1821     const DWARFDIE &die,
1822     TypeSystemClang::TemplateParameterInfos &template_param_infos) {
1823   const dw_tag_t tag = die.Tag();
1824   bool is_template_template_argument = false;
1825 
1826   switch (tag) {
1827   case DW_TAG_GNU_template_parameter_pack: {
1828     template_param_infos.packed_args =
1829         std::make_unique<TypeSystemClang::TemplateParameterInfos>();
1830     for (DWARFDIE child_die : die.children()) {
1831       if (!ParseTemplateDIE(child_die, *template_param_infos.packed_args))
1832         return false;
1833     }
1834     if (const char *name = die.GetName()) {
1835       template_param_infos.pack_name = name;
1836     }
1837     return true;
1838   }
1839   case DW_TAG_GNU_template_template_param:
1840     is_template_template_argument = true;
1841     LLVM_FALLTHROUGH;
1842   case DW_TAG_template_type_parameter:
1843   case DW_TAG_template_value_parameter: {
1844     DWARFAttributes attributes;
1845     const size_t num_attributes = die.GetAttributes(attributes);
1846     const char *name = nullptr;
1847     const char *template_name = nullptr;
1848     CompilerType clang_type;
1849     uint64_t uval64 = 0;
1850     bool uval64_valid = false;
1851     if (num_attributes > 0) {
1852       DWARFFormValue form_value;
1853       for (size_t i = 0; i < num_attributes; ++i) {
1854         const dw_attr_t attr = attributes.AttributeAtIndex(i);
1855 
1856         switch (attr) {
1857         case DW_AT_name:
1858           if (attributes.ExtractFormValueAtIndex(i, form_value))
1859             name = form_value.AsCString();
1860           break;
1861 
1862         case DW_AT_GNU_template_name:
1863           if (attributes.ExtractFormValueAtIndex(i, form_value))
1864             template_name = form_value.AsCString();
1865           break;
1866 
1867         case DW_AT_type:
1868           if (attributes.ExtractFormValueAtIndex(i, form_value)) {
1869             Type *lldb_type = die.ResolveTypeUID(form_value.Reference());
1870             if (lldb_type)
1871               clang_type = lldb_type->GetForwardCompilerType();
1872           }
1873           break;
1874 
1875         case DW_AT_const_value:
1876           if (attributes.ExtractFormValueAtIndex(i, form_value)) {
1877             uval64_valid = true;
1878             uval64 = form_value.Unsigned();
1879           }
1880           break;
1881         default:
1882           break;
1883         }
1884       }
1885 
1886       clang::ASTContext &ast = m_ast.getASTContext();
1887       if (!clang_type)
1888         clang_type = m_ast.GetBasicType(eBasicTypeVoid);
1889 
1890       if (!is_template_template_argument) {
1891         bool is_signed = false;
1892         if (name && name[0])
1893           template_param_infos.names.push_back(name);
1894         else
1895           template_param_infos.names.push_back(NULL);
1896 
1897         // Get the signed value for any integer or enumeration if available
1898         clang_type.IsIntegerOrEnumerationType(is_signed);
1899 
1900         if (tag == DW_TAG_template_value_parameter && uval64_valid) {
1901           llvm::Optional<uint64_t> size = clang_type.GetBitSize(nullptr);
1902           if (!size)
1903             return false;
1904           llvm::APInt apint(*size, uval64, is_signed);
1905           template_param_infos.args.push_back(
1906               clang::TemplateArgument(ast, llvm::APSInt(apint, !is_signed),
1907                                       ClangUtil::GetQualType(clang_type)));
1908         } else {
1909           template_param_infos.args.push_back(
1910               clang::TemplateArgument(ClangUtil::GetQualType(clang_type)));
1911         }
1912       } else {
1913         auto *tplt_type = m_ast.CreateTemplateTemplateParmDecl(template_name);
1914         template_param_infos.names.push_back(name);
1915         template_param_infos.args.push_back(
1916             clang::TemplateArgument(clang::TemplateName(tplt_type)));
1917       }
1918     }
1919   }
1920     return true;
1921 
1922   default:
1923     break;
1924   }
1925   return false;
1926 }
1927 
1928 bool DWARFASTParserClang::ParseTemplateParameterInfos(
1929     const DWARFDIE &parent_die,
1930     TypeSystemClang::TemplateParameterInfos &template_param_infos) {
1931 
1932   if (!parent_die)
1933     return false;
1934 
1935   for (DWARFDIE die : parent_die.children()) {
1936     const dw_tag_t tag = die.Tag();
1937 
1938     switch (tag) {
1939     case DW_TAG_template_type_parameter:
1940     case DW_TAG_template_value_parameter:
1941     case DW_TAG_GNU_template_parameter_pack:
1942     case DW_TAG_GNU_template_template_param:
1943       ParseTemplateDIE(die, template_param_infos);
1944       break;
1945 
1946     default:
1947       break;
1948     }
1949   }
1950   return template_param_infos.args.size() == template_param_infos.names.size();
1951 }
1952 
1953 bool DWARFASTParserClang::CompleteRecordType(const DWARFDIE &die,
1954                                              lldb_private::Type *type,
1955                                              CompilerType &clang_type) {
1956   const dw_tag_t tag = die.Tag();
1957   SymbolFileDWARF *dwarf = die.GetDWARF();
1958 
1959   ClangASTImporter::LayoutInfo layout_info;
1960 
1961   if (die.HasChildren()) {
1962     const bool type_is_objc_object_or_interface =
1963         TypeSystemClang::IsObjCObjectOrInterfaceType(clang_type);
1964     if (type_is_objc_object_or_interface) {
1965       // For objective C we don't start the definition when the class is
1966       // created.
1967       TypeSystemClang::StartTagDeclarationDefinition(clang_type);
1968     }
1969 
1970     int tag_decl_kind = -1;
1971     AccessType default_accessibility = eAccessNone;
1972     if (tag == DW_TAG_structure_type) {
1973       tag_decl_kind = clang::TTK_Struct;
1974       default_accessibility = eAccessPublic;
1975     } else if (tag == DW_TAG_union_type) {
1976       tag_decl_kind = clang::TTK_Union;
1977       default_accessibility = eAccessPublic;
1978     } else if (tag == DW_TAG_class_type) {
1979       tag_decl_kind = clang::TTK_Class;
1980       default_accessibility = eAccessPrivate;
1981     }
1982 
1983     std::vector<std::unique_ptr<clang::CXXBaseSpecifier>> bases;
1984     // Parse members and base classes first
1985     std::vector<DWARFDIE> member_function_dies;
1986 
1987     DelayedPropertyList delayed_properties;
1988     ParseChildMembers(die, clang_type, bases, member_function_dies,
1989                       delayed_properties, default_accessibility, layout_info);
1990 
1991     // Now parse any methods if there were any...
1992     for (const DWARFDIE &die : member_function_dies)
1993       dwarf->ResolveType(die);
1994 
1995     if (type_is_objc_object_or_interface) {
1996       ConstString class_name(clang_type.GetTypeName());
1997       if (class_name) {
1998         dwarf->GetObjCMethods(class_name, [&](DWARFDIE method_die) {
1999           method_die.ResolveType();
2000           return true;
2001         });
2002 
2003         for (DelayedPropertyList::iterator pi = delayed_properties.begin(),
2004                                            pe = delayed_properties.end();
2005              pi != pe; ++pi)
2006           pi->Finalize();
2007       }
2008     }
2009 
2010     if (!bases.empty()) {
2011       // Make sure all base classes refer to complete types and not forward
2012       // declarations. If we don't do this, clang will crash with an
2013       // assertion in the call to clang_type.TransferBaseClasses()
2014       for (const auto &base_class : bases) {
2015         clang::TypeSourceInfo *type_source_info =
2016             base_class->getTypeSourceInfo();
2017         if (type_source_info)
2018           RequireCompleteType(m_ast.GetType(type_source_info->getType()));
2019       }
2020 
2021       m_ast.TransferBaseClasses(clang_type.GetOpaqueQualType(),
2022                                 std::move(bases));
2023     }
2024   }
2025 
2026   m_ast.AddMethodOverridesForCXXRecordType(clang_type.GetOpaqueQualType());
2027   TypeSystemClang::BuildIndirectFields(clang_type);
2028   TypeSystemClang::CompleteTagDeclarationDefinition(clang_type);
2029 
2030   if (!layout_info.field_offsets.empty() || !layout_info.base_offsets.empty() ||
2031       !layout_info.vbase_offsets.empty()) {
2032     if (type)
2033       layout_info.bit_size = type->GetByteSize(nullptr).getValueOr(0) * 8;
2034     if (layout_info.bit_size == 0)
2035       layout_info.bit_size =
2036           die.GetAttributeValueAsUnsigned(DW_AT_byte_size, 0) * 8;
2037 
2038     clang::CXXRecordDecl *record_decl =
2039         m_ast.GetAsCXXRecordDecl(clang_type.GetOpaqueQualType());
2040     if (record_decl)
2041       GetClangASTImporter().SetRecordLayout(record_decl, layout_info);
2042   }
2043 
2044   return (bool)clang_type;
2045 }
2046 
2047 bool DWARFASTParserClang::CompleteEnumType(const DWARFDIE &die,
2048                                            lldb_private::Type *type,
2049                                            CompilerType &clang_type) {
2050   if (TypeSystemClang::StartTagDeclarationDefinition(clang_type)) {
2051     if (die.HasChildren()) {
2052       bool is_signed = false;
2053       clang_type.IsIntegerType(is_signed);
2054       ParseChildEnumerators(clang_type, is_signed,
2055                             type->GetByteSize(nullptr).getValueOr(0), die);
2056     }
2057     TypeSystemClang::CompleteTagDeclarationDefinition(clang_type);
2058   }
2059   return (bool)clang_type;
2060 }
2061 
2062 bool DWARFASTParserClang::CompleteTypeFromDWARF(const DWARFDIE &die,
2063                                                 lldb_private::Type *type,
2064                                                 CompilerType &clang_type) {
2065   SymbolFileDWARF *dwarf = die.GetDWARF();
2066 
2067   std::lock_guard<std::recursive_mutex> guard(
2068       dwarf->GetObjectFile()->GetModule()->GetMutex());
2069 
2070   // Disable external storage for this type so we don't get anymore
2071   // clang::ExternalASTSource queries for this type.
2072   m_ast.SetHasExternalStorage(clang_type.GetOpaqueQualType(), false);
2073 
2074   if (!die)
2075     return false;
2076 
2077   const dw_tag_t tag = die.Tag();
2078 
2079   Log *log =
2080       nullptr; // (LogChannelDWARF::GetLogIfAny(DWARF_LOG_DEBUG_INFO|DWARF_LOG_TYPE_COMPLETION));
2081   if (log)
2082     dwarf->GetObjectFile()->GetModule()->LogMessageVerboseBacktrace(
2083         log, "0x%8.8" PRIx64 ": %s '%s' resolving forward declaration...",
2084         die.GetID(), die.GetTagAsCString(), type->GetName().AsCString());
2085   assert(clang_type);
2086   DWARFAttributes attributes;
2087   switch (tag) {
2088   case DW_TAG_structure_type:
2089   case DW_TAG_union_type:
2090   case DW_TAG_class_type:
2091     return CompleteRecordType(die, type, clang_type);
2092   case DW_TAG_enumeration_type:
2093     return CompleteEnumType(die, type, clang_type);
2094   default:
2095     assert(false && "not a forward clang type decl!");
2096     break;
2097   }
2098 
2099   return false;
2100 }
2101 
2102 void DWARFASTParserClang::EnsureAllDIEsInDeclContextHaveBeenParsed(
2103     lldb_private::CompilerDeclContext decl_context) {
2104   auto opaque_decl_ctx =
2105       (clang::DeclContext *)decl_context.GetOpaqueDeclContext();
2106   for (auto it = m_decl_ctx_to_die.find(opaque_decl_ctx);
2107        it != m_decl_ctx_to_die.end() && it->first == opaque_decl_ctx;
2108        it = m_decl_ctx_to_die.erase(it))
2109     for (DWARFDIE decl : it->second.children())
2110       GetClangDeclForDIE(decl);
2111 }
2112 
2113 CompilerDecl DWARFASTParserClang::GetDeclForUIDFromDWARF(const DWARFDIE &die) {
2114   clang::Decl *clang_decl = GetClangDeclForDIE(die);
2115   if (clang_decl != nullptr)
2116     return m_ast.GetCompilerDecl(clang_decl);
2117   return CompilerDecl();
2118 }
2119 
2120 CompilerDeclContext
2121 DWARFASTParserClang::GetDeclContextForUIDFromDWARF(const DWARFDIE &die) {
2122   clang::DeclContext *clang_decl_ctx = GetClangDeclContextForDIE(die);
2123   if (clang_decl_ctx)
2124     return m_ast.CreateDeclContext(clang_decl_ctx);
2125   return CompilerDeclContext();
2126 }
2127 
2128 CompilerDeclContext
2129 DWARFASTParserClang::GetDeclContextContainingUIDFromDWARF(const DWARFDIE &die) {
2130   clang::DeclContext *clang_decl_ctx =
2131       GetClangDeclContextContainingDIE(die, nullptr);
2132   if (clang_decl_ctx)
2133     return m_ast.CreateDeclContext(clang_decl_ctx);
2134   return CompilerDeclContext();
2135 }
2136 
2137 size_t DWARFASTParserClang::ParseChildEnumerators(
2138     lldb_private::CompilerType &clang_type, bool is_signed,
2139     uint32_t enumerator_byte_size, const DWARFDIE &parent_die) {
2140   if (!parent_die)
2141     return 0;
2142 
2143   size_t enumerators_added = 0;
2144 
2145   for (DWARFDIE die : parent_die.children()) {
2146     const dw_tag_t tag = die.Tag();
2147     if (tag == DW_TAG_enumerator) {
2148       DWARFAttributes attributes;
2149       const size_t num_child_attributes = die.GetAttributes(attributes);
2150       if (num_child_attributes > 0) {
2151         const char *name = nullptr;
2152         bool got_value = false;
2153         int64_t enum_value = 0;
2154         Declaration decl;
2155 
2156         uint32_t i;
2157         for (i = 0; i < num_child_attributes; ++i) {
2158           const dw_attr_t attr = attributes.AttributeAtIndex(i);
2159           DWARFFormValue form_value;
2160           if (attributes.ExtractFormValueAtIndex(i, form_value)) {
2161             switch (attr) {
2162             case DW_AT_const_value:
2163               got_value = true;
2164               if (is_signed)
2165                 enum_value = form_value.Signed();
2166               else
2167                 enum_value = form_value.Unsigned();
2168               break;
2169 
2170             case DW_AT_name:
2171               name = form_value.AsCString();
2172               break;
2173 
2174             case DW_AT_description:
2175             default:
2176             case DW_AT_decl_file:
2177               decl.SetFile(attributes.CompileUnitAtIndex(i)->GetFile(
2178                   form_value.Unsigned()));
2179               break;
2180             case DW_AT_decl_line:
2181               decl.SetLine(form_value.Unsigned());
2182               break;
2183             case DW_AT_decl_column:
2184               decl.SetColumn(form_value.Unsigned());
2185               break;
2186             case DW_AT_sibling:
2187               break;
2188             }
2189           }
2190         }
2191 
2192         if (name && name[0] && got_value) {
2193           m_ast.AddEnumerationValueToEnumerationType(
2194               clang_type, decl, name, enum_value, enumerator_byte_size * 8);
2195           ++enumerators_added;
2196         }
2197       }
2198     }
2199   }
2200   return enumerators_added;
2201 }
2202 
2203 Function *DWARFASTParserClang::ParseFunctionFromDWARF(CompileUnit &comp_unit,
2204                                                       const DWARFDIE &die) {
2205   DWARFRangeList func_ranges;
2206   const char *name = nullptr;
2207   const char *mangled = nullptr;
2208   int decl_file = 0;
2209   int decl_line = 0;
2210   int decl_column = 0;
2211   int call_file = 0;
2212   int call_line = 0;
2213   int call_column = 0;
2214   DWARFExpression frame_base;
2215 
2216   const dw_tag_t tag = die.Tag();
2217 
2218   if (tag != DW_TAG_subprogram)
2219     return nullptr;
2220 
2221   if (die.GetDIENamesAndRanges(name, mangled, func_ranges, decl_file, decl_line,
2222                                decl_column, call_file, call_line, call_column,
2223                                &frame_base)) {
2224 
2225     // Union of all ranges in the function DIE (if the function is
2226     // discontiguous)
2227     AddressRange func_range;
2228     lldb::addr_t lowest_func_addr = func_ranges.GetMinRangeBase(0);
2229     lldb::addr_t highest_func_addr = func_ranges.GetMaxRangeEnd(0);
2230     if (lowest_func_addr != LLDB_INVALID_ADDRESS &&
2231         lowest_func_addr <= highest_func_addr) {
2232       ModuleSP module_sp(die.GetModule());
2233       func_range.GetBaseAddress().ResolveAddressUsingFileSections(
2234           lowest_func_addr, module_sp->GetSectionList());
2235       if (func_range.GetBaseAddress().IsValid())
2236         func_range.SetByteSize(highest_func_addr - lowest_func_addr);
2237     }
2238 
2239     if (func_range.GetBaseAddress().IsValid()) {
2240       Mangled func_name;
2241       if (mangled)
2242         func_name.SetValue(ConstString(mangled), true);
2243       else if ((die.GetParent().Tag() == DW_TAG_compile_unit ||
2244                 die.GetParent().Tag() == DW_TAG_partial_unit) &&
2245                Language::LanguageIsCPlusPlus(
2246                    SymbolFileDWARF::GetLanguage(*die.GetCU())) &&
2247                !Language::LanguageIsObjC(
2248                    SymbolFileDWARF::GetLanguage(*die.GetCU())) &&
2249                name && strcmp(name, "main") != 0) {
2250         // If the mangled name is not present in the DWARF, generate the
2251         // demangled name using the decl context. We skip if the function is
2252         // "main" as its name is never mangled.
2253         bool is_static = false;
2254         bool is_variadic = false;
2255         bool has_template_params = false;
2256         unsigned type_quals = 0;
2257         std::vector<CompilerType> param_types;
2258         std::vector<clang::ParmVarDecl *> param_decls;
2259         StreamString sstr;
2260 
2261         DWARFDeclContext decl_ctx = SymbolFileDWARF::GetDWARFDeclContext(die);
2262         sstr << decl_ctx.GetQualifiedName();
2263 
2264         clang::DeclContext *containing_decl_ctx =
2265             GetClangDeclContextContainingDIE(die, nullptr);
2266         ParseChildParameters(containing_decl_ctx, die, true, is_static,
2267                              is_variadic, has_template_params, param_types,
2268                              param_decls, type_quals);
2269         sstr << "(";
2270         for (size_t i = 0; i < param_types.size(); i++) {
2271           if (i > 0)
2272             sstr << ", ";
2273           sstr << param_types[i].GetTypeName();
2274         }
2275         if (is_variadic)
2276           sstr << ", ...";
2277         sstr << ")";
2278         if (type_quals & clang::Qualifiers::Const)
2279           sstr << " const";
2280 
2281         func_name.SetValue(ConstString(sstr.GetString()), false);
2282       } else
2283         func_name.SetValue(ConstString(name), false);
2284 
2285       FunctionSP func_sp;
2286       std::unique_ptr<Declaration> decl_up;
2287       if (decl_file != 0 || decl_line != 0 || decl_column != 0)
2288         decl_up = std::make_unique<Declaration>(die.GetCU()->GetFile(decl_file),
2289                                                 decl_line, decl_column);
2290 
2291       SymbolFileDWARF *dwarf = die.GetDWARF();
2292       // Supply the type _only_ if it has already been parsed
2293       Type *func_type = dwarf->GetDIEToType().lookup(die.GetDIE());
2294 
2295       assert(func_type == nullptr || func_type != DIE_IS_BEING_PARSED);
2296 
2297       if (dwarf->FixupAddress(func_range.GetBaseAddress())) {
2298         const user_id_t func_user_id = die.GetID();
2299         func_sp =
2300             std::make_shared<Function>(&comp_unit,
2301                                    func_user_id, // UserID is the DIE offset
2302                                    func_user_id, func_name, func_type,
2303                                        func_range); // first address range
2304 
2305         if (func_sp.get() != nullptr) {
2306           if (frame_base.IsValid())
2307             func_sp->GetFrameBaseExpression() = frame_base;
2308           comp_unit.AddFunction(func_sp);
2309           return func_sp.get();
2310         }
2311       }
2312     }
2313   }
2314   return nullptr;
2315 }
2316 
2317 void DWARFASTParserClang::ParseSingleMember(
2318     const DWARFDIE &die, const DWARFDIE &parent_die,
2319     const lldb_private::CompilerType &class_clang_type,
2320     lldb::AccessType default_accessibility,
2321     DelayedPropertyList &delayed_properties,
2322     lldb_private::ClangASTImporter::LayoutInfo &layout_info,
2323     FieldInfo &last_field_info) {
2324   ModuleSP module_sp = parent_die.GetDWARF()->GetObjectFile()->GetModule();
2325   const dw_tag_t tag = die.Tag();
2326   // Get the parent byte size so we can verify any members will fit
2327   const uint64_t parent_byte_size =
2328       parent_die.GetAttributeValueAsUnsigned(DW_AT_byte_size, UINT64_MAX);
2329   const uint64_t parent_bit_size =
2330       parent_byte_size == UINT64_MAX ? UINT64_MAX : parent_byte_size * 8;
2331 
2332   DWARFAttributes attributes;
2333   const size_t num_attributes = die.GetAttributes(attributes);
2334   if (num_attributes == 0)
2335     return;
2336 
2337   const char *name = nullptr;
2338   const char *prop_name = nullptr;
2339   const char *prop_getter_name = nullptr;
2340   const char *prop_setter_name = nullptr;
2341   uint32_t prop_attributes = 0;
2342 
2343   bool is_artificial = false;
2344   DWARFFormValue encoding_form;
2345   AccessType accessibility = eAccessNone;
2346   uint32_t member_byte_offset =
2347       (parent_die.Tag() == DW_TAG_union_type) ? 0 : UINT32_MAX;
2348   llvm::Optional<uint64_t> byte_size;
2349   int64_t bit_offset = 0;
2350   uint64_t data_bit_offset = UINT64_MAX;
2351   size_t bit_size = 0;
2352   bool is_external =
2353       false; // On DW_TAG_members, this means the member is static
2354   uint32_t i;
2355   for (i = 0; i < num_attributes && !is_artificial; ++i) {
2356     const dw_attr_t attr = attributes.AttributeAtIndex(i);
2357     DWARFFormValue form_value;
2358     if (attributes.ExtractFormValueAtIndex(i, form_value)) {
2359       // DW_AT_data_member_location indicates the byte offset of the
2360       // word from the base address of the structure.
2361       //
2362       // DW_AT_bit_offset indicates how many bits into the word
2363       // (according to the host endianness) the low-order bit of the
2364       // field starts.  AT_bit_offset can be negative.
2365       //
2366       // DW_AT_bit_size indicates the size of the field in bits.
2367       switch (attr) {
2368       case DW_AT_name:
2369         name = form_value.AsCString();
2370         break;
2371       case DW_AT_type:
2372         encoding_form = form_value;
2373         break;
2374       case DW_AT_bit_offset:
2375         bit_offset = form_value.Signed();
2376         break;
2377       case DW_AT_bit_size:
2378         bit_size = form_value.Unsigned();
2379         break;
2380       case DW_AT_byte_size:
2381         byte_size = form_value.Unsigned();
2382         break;
2383       case DW_AT_data_bit_offset:
2384         data_bit_offset = form_value.Unsigned();
2385         break;
2386       case DW_AT_data_member_location:
2387         if (form_value.BlockData()) {
2388           Value initialValue(0);
2389           Value memberOffset(0);
2390           const DWARFDataExtractor &debug_info_data = die.GetData();
2391           uint32_t block_length = form_value.Unsigned();
2392           uint32_t block_offset =
2393               form_value.BlockData() - debug_info_data.GetDataStart();
2394           if (DWARFExpression::Evaluate(
2395                   nullptr, // ExecutionContext *
2396                   nullptr, // RegisterContext *
2397                   module_sp,
2398                   DataExtractor(debug_info_data, block_offset, block_length),
2399                   die.GetCU(), eRegisterKindDWARF, &initialValue, nullptr,
2400                   memberOffset, nullptr)) {
2401             member_byte_offset = memberOffset.ResolveValue(nullptr).UInt();
2402           }
2403         } else {
2404           // With DWARF 3 and later, if the value is an integer constant,
2405           // this form value is the offset in bytes from the beginning of
2406           // the containing entity.
2407           member_byte_offset = form_value.Unsigned();
2408         }
2409         break;
2410 
2411       case DW_AT_accessibility:
2412         accessibility = DW_ACCESS_to_AccessType(form_value.Unsigned());
2413         break;
2414       case DW_AT_artificial:
2415         is_artificial = form_value.Boolean();
2416         break;
2417       case DW_AT_APPLE_property_name:
2418         prop_name = form_value.AsCString();
2419         break;
2420       case DW_AT_APPLE_property_getter:
2421         prop_getter_name = form_value.AsCString();
2422         break;
2423       case DW_AT_APPLE_property_setter:
2424         prop_setter_name = form_value.AsCString();
2425         break;
2426       case DW_AT_APPLE_property_attribute:
2427         prop_attributes = form_value.Unsigned();
2428         break;
2429       case DW_AT_external:
2430         is_external = form_value.Boolean();
2431         break;
2432 
2433       default:
2434       case DW_AT_declaration:
2435       case DW_AT_description:
2436       case DW_AT_mutable:
2437       case DW_AT_visibility:
2438       case DW_AT_sibling:
2439         break;
2440       }
2441     }
2442   }
2443 
2444   if (prop_name) {
2445     ConstString fixed_setter;
2446 
2447     // Check if the property getter/setter were provided as full names.
2448     // We want basenames, so we extract them.
2449 
2450     if (prop_getter_name && prop_getter_name[0] == '-') {
2451       ObjCLanguage::MethodName prop_getter_method(prop_getter_name, true);
2452       prop_getter_name = prop_getter_method.GetSelector().GetCString();
2453     }
2454 
2455     if (prop_setter_name && prop_setter_name[0] == '-') {
2456       ObjCLanguage::MethodName prop_setter_method(prop_setter_name, true);
2457       prop_setter_name = prop_setter_method.GetSelector().GetCString();
2458     }
2459 
2460     // If the names haven't been provided, they need to be filled in.
2461 
2462     if (!prop_getter_name) {
2463       prop_getter_name = prop_name;
2464     }
2465     if (!prop_setter_name && prop_name[0] &&
2466         !(prop_attributes & DW_APPLE_PROPERTY_readonly)) {
2467       StreamString ss;
2468 
2469       ss.Printf("set%c%s:", toupper(prop_name[0]), &prop_name[1]);
2470 
2471       fixed_setter.SetString(ss.GetString());
2472       prop_setter_name = fixed_setter.GetCString();
2473     }
2474   }
2475 
2476   // Clang has a DWARF generation bug where sometimes it represents
2477   // fields that are references with bad byte size and bit size/offset
2478   // information such as:
2479   //
2480   //  DW_AT_byte_size( 0x00 )
2481   //  DW_AT_bit_size( 0x40 )
2482   //  DW_AT_bit_offset( 0xffffffffffffffc0 )
2483   //
2484   // So check the bit offset to make sure it is sane, and if the values
2485   // are not sane, remove them. If we don't do this then we will end up
2486   // with a crash if we try to use this type in an expression when clang
2487   // becomes unhappy with its recycled debug info.
2488 
2489   if (byte_size.getValueOr(0) == 0 && bit_offset < 0) {
2490     bit_size = 0;
2491     bit_offset = 0;
2492   }
2493 
2494   const bool class_is_objc_object_or_interface =
2495       TypeSystemClang::IsObjCObjectOrInterfaceType(class_clang_type);
2496 
2497   // FIXME: Make Clang ignore Objective-C accessibility for expressions
2498   if (class_is_objc_object_or_interface)
2499     accessibility = eAccessNone;
2500 
2501   // Handle static members
2502   if (is_external && member_byte_offset == UINT32_MAX) {
2503     Type *var_type = die.ResolveTypeUID(encoding_form.Reference());
2504 
2505     if (var_type) {
2506       if (accessibility == eAccessNone)
2507         accessibility = eAccessPublic;
2508       TypeSystemClang::AddVariableToRecordType(
2509           class_clang_type, name, var_type->GetForwardCompilerType(),
2510           accessibility);
2511     }
2512     return;
2513   }
2514 
2515   if (!is_artificial) {
2516     Type *member_type = die.ResolveTypeUID(encoding_form.Reference());
2517 
2518     clang::FieldDecl *field_decl = nullptr;
2519     const uint64_t character_width = 8;
2520     const uint64_t word_width = 32;
2521     if (tag == DW_TAG_member) {
2522       if (member_type) {
2523         CompilerType member_clang_type = member_type->GetLayoutCompilerType();
2524 
2525         if (accessibility == eAccessNone)
2526           accessibility = default_accessibility;
2527 
2528         uint64_t field_bit_offset =
2529             (member_byte_offset == UINT32_MAX ? 0 : (member_byte_offset * 8));
2530 
2531         if (bit_size > 0) {
2532           FieldInfo this_field_info;
2533           this_field_info.bit_offset = field_bit_offset;
2534           this_field_info.bit_size = bit_size;
2535 
2536           if (data_bit_offset != UINT64_MAX) {
2537             this_field_info.bit_offset = data_bit_offset;
2538           } else {
2539             if (!byte_size)
2540               byte_size = member_type->GetByteSize(nullptr);
2541 
2542             ObjectFile *objfile = die.GetDWARF()->GetObjectFile();
2543             if (objfile->GetByteOrder() == eByteOrderLittle) {
2544               this_field_info.bit_offset += byte_size.getValueOr(0) * 8;
2545               this_field_info.bit_offset -= (bit_offset + bit_size);
2546             } else {
2547               this_field_info.bit_offset += bit_offset;
2548             }
2549           }
2550 
2551           // The ObjC runtime knows the byte offset but we still need to provide
2552           // the bit-offset in the layout. It just means something different then
2553           // what it does in C and C++. So we skip this check for ObjC types.
2554           //
2555           // We also skip this for fields of a union since they will all have a
2556           // zero offset.
2557           if (!TypeSystemClang::IsObjCObjectOrInterfaceType(class_clang_type) &&
2558               !(parent_die.Tag() == DW_TAG_union_type && this_field_info.bit_offset == 0) &&
2559               ((this_field_info.bit_offset >= parent_bit_size) ||
2560                (last_field_info.IsBitfield() &&
2561                 !last_field_info.NextBitfieldOffsetIsValid(
2562                     this_field_info.bit_offset)))) {
2563             ObjectFile *objfile = die.GetDWARF()->GetObjectFile();
2564             objfile->GetModule()->ReportWarning(
2565                 "0x%8.8" PRIx64 ": %s bitfield named \"%s\" has invalid "
2566                 "bit offset (0x%8.8" PRIx64
2567                 ") member will be ignored. Please file a bug against the "
2568                 "compiler and include the preprocessed output for %s\n",
2569                 die.GetID(), DW_TAG_value_to_name(tag), name,
2570                 this_field_info.bit_offset, GetUnitName(parent_die).c_str());
2571             return;
2572           }
2573 
2574           // Update the field bit offset we will report for layout
2575           field_bit_offset = this_field_info.bit_offset;
2576 
2577           // Objective-C has invalid DW_AT_bit_offset values in older
2578           // versions of clang, so we have to be careful and only insert
2579           // unnamed bitfields if we have a new enough clang.
2580           bool detect_unnamed_bitfields = true;
2581 
2582           if (class_is_objc_object_or_interface)
2583             detect_unnamed_bitfields =
2584                 die.GetCU()->Supports_unnamed_objc_bitfields();
2585 
2586           if (detect_unnamed_bitfields) {
2587             clang::Optional<FieldInfo> unnamed_field_info;
2588             uint64_t last_field_end = 0;
2589 
2590             last_field_end =
2591                 last_field_info.bit_offset + last_field_info.bit_size;
2592 
2593             if (!last_field_info.IsBitfield()) {
2594               // The last field was not a bit-field...
2595               // but if it did take up the entire word then we need to extend
2596               // last_field_end so the bit-field does not step into the last
2597               // fields padding.
2598               if (last_field_end != 0 && ((last_field_end % word_width) != 0))
2599                 last_field_end += word_width - (last_field_end % word_width);
2600             }
2601 
2602             // If we have a gap between the last_field_end and the current
2603             // field we have an unnamed bit-field.
2604             // If we have a base class, we assume there is no unnamed
2605             // bit-field if this is the first field since the gap can be
2606             // attributed to the members from the base class. This assumption
2607             // is not correct if the first field of the derived class is
2608             // indeed an unnamed bit-field. We currently do not have the
2609             // machinary to track the offset of the last field of classes we
2610             // have seen before, so we are not handling this case.
2611             if (this_field_info.bit_offset != last_field_end &&
2612                 this_field_info.bit_offset > last_field_end &&
2613                 !(last_field_info.bit_offset == 0 &&
2614                   last_field_info.bit_size == 0 &&
2615                   layout_info.base_offsets.size() != 0)) {
2616               unnamed_field_info = FieldInfo{};
2617               unnamed_field_info->bit_size =
2618                   this_field_info.bit_offset - last_field_end;
2619               unnamed_field_info->bit_offset = last_field_end;
2620             }
2621 
2622             if (unnamed_field_info) {
2623               clang::FieldDecl *unnamed_bitfield_decl =
2624                   TypeSystemClang::AddFieldToRecordType(
2625                       class_clang_type, llvm::StringRef(),
2626                       m_ast.GetBuiltinTypeForEncodingAndBitSize(eEncodingSint,
2627                                                                 word_width),
2628                       accessibility, unnamed_field_info->bit_size);
2629 
2630               layout_info.field_offsets.insert(std::make_pair(
2631                   unnamed_bitfield_decl, unnamed_field_info->bit_offset));
2632             }
2633           }
2634 
2635           last_field_info = this_field_info;
2636           last_field_info.SetIsBitfield(true);
2637         } else {
2638           last_field_info.bit_offset = field_bit_offset;
2639 
2640           if (llvm::Optional<uint64_t> clang_type_size =
2641                   member_type->GetByteSize(nullptr)) {
2642             last_field_info.bit_size = *clang_type_size * character_width;
2643           }
2644 
2645           last_field_info.SetIsBitfield(false);
2646         }
2647 
2648         if (!member_clang_type.IsCompleteType())
2649           member_clang_type.GetCompleteType();
2650 
2651         {
2652           // Older versions of clang emit array[0] and array[1] in the
2653           // same way (<rdar://problem/12566646>). If the current field
2654           // is at the end of the structure, then there is definitely no
2655           // room for extra elements and we override the type to
2656           // array[0].
2657 
2658           CompilerType member_array_element_type;
2659           uint64_t member_array_size;
2660           bool member_array_is_incomplete;
2661 
2662           if (member_clang_type.IsArrayType(&member_array_element_type,
2663                                             &member_array_size,
2664                                             &member_array_is_incomplete) &&
2665               !member_array_is_incomplete) {
2666             uint64_t parent_byte_size =
2667                 parent_die.GetAttributeValueAsUnsigned(DW_AT_byte_size,
2668                                                        UINT64_MAX);
2669 
2670             if (member_byte_offset >= parent_byte_size) {
2671               if (member_array_size != 1 &&
2672                   (member_array_size != 0 ||
2673                    member_byte_offset > parent_byte_size)) {
2674                 module_sp->ReportError(
2675                     "0x%8.8" PRIx64
2676                     ": DW_TAG_member '%s' refers to type 0x%8.8x"
2677                     " which extends beyond the bounds of 0x%8.8" PRIx64,
2678                     die.GetID(), name, encoding_form.Reference().GetOffset(),
2679                     parent_die.GetID());
2680               }
2681 
2682               member_clang_type =
2683                   m_ast.CreateArrayType(member_array_element_type, 0, false);
2684             }
2685           }
2686         }
2687 
2688         RequireCompleteType(member_clang_type);
2689 
2690         field_decl = TypeSystemClang::AddFieldToRecordType(
2691             class_clang_type, name, member_clang_type, accessibility,
2692             bit_size);
2693 
2694         m_ast.SetMetadataAsUserID(field_decl, die.GetID());
2695 
2696         layout_info.field_offsets.insert(
2697             std::make_pair(field_decl, field_bit_offset));
2698       } else {
2699         if (name)
2700           module_sp->ReportError(
2701               "0x%8.8" PRIx64 ": DW_TAG_member '%s' refers to type 0x%8.8x"
2702               " which was unable to be parsed",
2703               die.GetID(), name, encoding_form.Reference().GetOffset());
2704         else
2705           module_sp->ReportError(
2706               "0x%8.8" PRIx64 ": DW_TAG_member refers to type 0x%8.8x"
2707               " which was unable to be parsed",
2708               die.GetID(), encoding_form.Reference().GetOffset());
2709       }
2710     }
2711 
2712     if (prop_name != nullptr && member_type) {
2713       clang::ObjCIvarDecl *ivar_decl = nullptr;
2714 
2715       if (field_decl) {
2716         ivar_decl = clang::dyn_cast<clang::ObjCIvarDecl>(field_decl);
2717         assert(ivar_decl != nullptr);
2718       }
2719 
2720       ClangASTMetadata metadata;
2721       metadata.SetUserID(die.GetID());
2722       delayed_properties.push_back(DelayedAddObjCClassProperty(
2723           class_clang_type, prop_name, member_type->GetLayoutCompilerType(),
2724           ivar_decl, prop_setter_name, prop_getter_name, prop_attributes,
2725           &metadata));
2726 
2727       if (ivar_decl)
2728         m_ast.SetMetadataAsUserID(ivar_decl, die.GetID());
2729     }
2730   }
2731 }
2732 
2733 bool DWARFASTParserClang::ParseChildMembers(
2734     const DWARFDIE &parent_die, CompilerType &class_clang_type,
2735     std::vector<std::unique_ptr<clang::CXXBaseSpecifier>> &base_classes,
2736     std::vector<DWARFDIE> &member_function_dies,
2737     DelayedPropertyList &delayed_properties, AccessType &default_accessibility,
2738     ClangASTImporter::LayoutInfo &layout_info) {
2739   if (!parent_die)
2740     return false;
2741 
2742   FieldInfo last_field_info;
2743 
2744   ModuleSP module_sp = parent_die.GetDWARF()->GetObjectFile()->GetModule();
2745   TypeSystemClang *ast =
2746       llvm::dyn_cast_or_null<TypeSystemClang>(class_clang_type.GetTypeSystem());
2747   if (ast == nullptr)
2748     return false;
2749 
2750   for (DWARFDIE die : parent_die.children()) {
2751     dw_tag_t tag = die.Tag();
2752 
2753     switch (tag) {
2754     case DW_TAG_member:
2755     case DW_TAG_APPLE_property:
2756       ParseSingleMember(die, parent_die, class_clang_type,
2757                         default_accessibility, delayed_properties, layout_info,
2758                         last_field_info);
2759       break;
2760 
2761     case DW_TAG_subprogram:
2762       // Let the type parsing code handle this one for us.
2763       member_function_dies.push_back(die);
2764       break;
2765 
2766     case DW_TAG_inheritance: {
2767       // TODO: implement DW_TAG_inheritance type parsing
2768       DWARFAttributes attributes;
2769       const size_t num_attributes = die.GetAttributes(attributes);
2770       if (num_attributes > 0) {
2771         DWARFFormValue encoding_form;
2772         AccessType accessibility = default_accessibility;
2773         bool is_virtual = false;
2774         bool is_base_of_class = true;
2775         off_t member_byte_offset = 0;
2776         uint32_t i;
2777         for (i = 0; i < num_attributes; ++i) {
2778           const dw_attr_t attr = attributes.AttributeAtIndex(i);
2779           DWARFFormValue form_value;
2780           if (attributes.ExtractFormValueAtIndex(i, form_value)) {
2781             switch (attr) {
2782             case DW_AT_type:
2783               encoding_form = form_value;
2784               break;
2785             case DW_AT_data_member_location:
2786               if (form_value.BlockData()) {
2787                 Value initialValue(0);
2788                 Value memberOffset(0);
2789                 const DWARFDataExtractor &debug_info_data = die.GetData();
2790                 uint32_t block_length = form_value.Unsigned();
2791                 uint32_t block_offset =
2792                     form_value.BlockData() - debug_info_data.GetDataStart();
2793                 if (DWARFExpression::Evaluate(
2794                         nullptr, nullptr, module_sp,
2795                         DataExtractor(debug_info_data, block_offset,
2796                                       block_length),
2797                         die.GetCU(), eRegisterKindDWARF, &initialValue, nullptr,
2798                         memberOffset, nullptr)) {
2799                   member_byte_offset =
2800                       memberOffset.ResolveValue(nullptr).UInt();
2801                 }
2802               } else {
2803                 // With DWARF 3 and later, if the value is an integer constant,
2804                 // this form value is the offset in bytes from the beginning of
2805                 // the containing entity.
2806                 member_byte_offset = form_value.Unsigned();
2807               }
2808               break;
2809 
2810             case DW_AT_accessibility:
2811               accessibility = DW_ACCESS_to_AccessType(form_value.Unsigned());
2812               break;
2813 
2814             case DW_AT_virtuality:
2815               is_virtual = form_value.Boolean();
2816               break;
2817 
2818             case DW_AT_sibling:
2819               break;
2820 
2821             default:
2822               break;
2823             }
2824           }
2825         }
2826 
2827         Type *base_class_type = die.ResolveTypeUID(encoding_form.Reference());
2828         if (base_class_type == nullptr) {
2829           module_sp->ReportError("0x%8.8x: DW_TAG_inheritance failed to "
2830                                  "resolve the base class at 0x%8.8x"
2831                                  " from enclosing type 0x%8.8x. \nPlease file "
2832                                  "a bug and attach the file at the start of "
2833                                  "this error message",
2834                                  die.GetOffset(),
2835                                  encoding_form.Reference().GetOffset(),
2836                                  parent_die.GetOffset());
2837           break;
2838         }
2839 
2840         CompilerType base_class_clang_type =
2841             base_class_type->GetFullCompilerType();
2842         assert(base_class_clang_type);
2843         if (TypeSystemClang::IsObjCObjectOrInterfaceType(class_clang_type)) {
2844           ast->SetObjCSuperClass(class_clang_type, base_class_clang_type);
2845         } else {
2846           std::unique_ptr<clang::CXXBaseSpecifier> result =
2847               ast->CreateBaseClassSpecifier(
2848                   base_class_clang_type.GetOpaqueQualType(), accessibility,
2849                   is_virtual, is_base_of_class);
2850           if (!result)
2851             break;
2852 
2853           base_classes.push_back(std::move(result));
2854 
2855           if (is_virtual) {
2856             // Do not specify any offset for virtual inheritance. The DWARF
2857             // produced by clang doesn't give us a constant offset, but gives
2858             // us a DWARF expressions that requires an actual object in memory.
2859             // the DW_AT_data_member_location for a virtual base class looks
2860             // like:
2861             //      DW_AT_data_member_location( DW_OP_dup, DW_OP_deref,
2862             //      DW_OP_constu(0x00000018), DW_OP_minus, DW_OP_deref,
2863             //      DW_OP_plus )
2864             // Given this, there is really no valid response we can give to
2865             // clang for virtual base class offsets, and this should eventually
2866             // be removed from LayoutRecordType() in the external
2867             // AST source in clang.
2868           } else {
2869             layout_info.base_offsets.insert(std::make_pair(
2870                 ast->GetAsCXXRecordDecl(
2871                     base_class_clang_type.GetOpaqueQualType()),
2872                 clang::CharUnits::fromQuantity(member_byte_offset)));
2873           }
2874         }
2875       }
2876     } break;
2877 
2878     default:
2879       break;
2880     }
2881   }
2882 
2883   return true;
2884 }
2885 
2886 size_t DWARFASTParserClang::ParseChildParameters(
2887     clang::DeclContext *containing_decl_ctx, const DWARFDIE &parent_die,
2888     bool skip_artificial, bool &is_static, bool &is_variadic,
2889     bool &has_template_params, std::vector<CompilerType> &function_param_types,
2890     std::vector<clang::ParmVarDecl *> &function_param_decls,
2891     unsigned &type_quals) {
2892   if (!parent_die)
2893     return 0;
2894 
2895   size_t arg_idx = 0;
2896   for (DWARFDIE die : parent_die.children()) {
2897     const dw_tag_t tag = die.Tag();
2898     switch (tag) {
2899     case DW_TAG_formal_parameter: {
2900       DWARFAttributes attributes;
2901       const size_t num_attributes = die.GetAttributes(attributes);
2902       if (num_attributes > 0) {
2903         const char *name = nullptr;
2904         DWARFFormValue param_type_die_form;
2905         bool is_artificial = false;
2906         // one of None, Auto, Register, Extern, Static, PrivateExtern
2907 
2908         clang::StorageClass storage = clang::SC_None;
2909         uint32_t i;
2910         for (i = 0; i < num_attributes; ++i) {
2911           const dw_attr_t attr = attributes.AttributeAtIndex(i);
2912           DWARFFormValue form_value;
2913           if (attributes.ExtractFormValueAtIndex(i, form_value)) {
2914             switch (attr) {
2915             case DW_AT_name:
2916               name = form_value.AsCString();
2917               break;
2918             case DW_AT_type:
2919               param_type_die_form = form_value;
2920               break;
2921             case DW_AT_artificial:
2922               is_artificial = form_value.Boolean();
2923               break;
2924             case DW_AT_location:
2925             case DW_AT_const_value:
2926             case DW_AT_default_value:
2927             case DW_AT_description:
2928             case DW_AT_endianity:
2929             case DW_AT_is_optional:
2930             case DW_AT_segment:
2931             case DW_AT_variable_parameter:
2932             default:
2933             case DW_AT_abstract_origin:
2934             case DW_AT_sibling:
2935               break;
2936             }
2937           }
2938         }
2939 
2940         bool skip = false;
2941         if (skip_artificial && is_artificial) {
2942           // In order to determine if a C++ member function is "const" we
2943           // have to look at the const-ness of "this"...
2944           if (arg_idx == 0 &&
2945               DeclKindIsCXXClass(containing_decl_ctx->getDeclKind()) &&
2946               // Often times compilers omit the "this" name for the
2947               // specification DIEs, so we can't rely upon the name being in
2948               // the formal parameter DIE...
2949               (name == nullptr || ::strcmp(name, "this") == 0)) {
2950             Type *this_type =
2951                 die.ResolveTypeUID(param_type_die_form.Reference());
2952             if (this_type) {
2953               uint32_t encoding_mask = this_type->GetEncodingMask();
2954               if (encoding_mask & Type::eEncodingIsPointerUID) {
2955                 is_static = false;
2956 
2957                 if (encoding_mask & (1u << Type::eEncodingIsConstUID))
2958                   type_quals |= clang::Qualifiers::Const;
2959                 if (encoding_mask & (1u << Type::eEncodingIsVolatileUID))
2960                   type_quals |= clang::Qualifiers::Volatile;
2961               }
2962             }
2963           }
2964           skip = true;
2965         }
2966 
2967         if (!skip) {
2968           Type *type = die.ResolveTypeUID(param_type_die_form.Reference());
2969           if (type) {
2970             function_param_types.push_back(type->GetForwardCompilerType());
2971 
2972             clang::ParmVarDecl *param_var_decl =
2973                 m_ast.CreateParameterDeclaration(
2974                     containing_decl_ctx, GetOwningClangModule(die), name,
2975                     type->GetForwardCompilerType(), storage);
2976             assert(param_var_decl);
2977             function_param_decls.push_back(param_var_decl);
2978 
2979             m_ast.SetMetadataAsUserID(param_var_decl, die.GetID());
2980           }
2981         }
2982       }
2983       arg_idx++;
2984     } break;
2985 
2986     case DW_TAG_unspecified_parameters:
2987       is_variadic = true;
2988       break;
2989 
2990     case DW_TAG_template_type_parameter:
2991     case DW_TAG_template_value_parameter:
2992     case DW_TAG_GNU_template_parameter_pack:
2993       // The one caller of this was never using the template_param_infos, and
2994       // the local variable was taking up a large amount of stack space in
2995       // SymbolFileDWARF::ParseType() so this was removed. If we ever need the
2996       // template params back, we can add them back.
2997       // ParseTemplateDIE (dwarf_cu, die, template_param_infos);
2998       has_template_params = true;
2999       break;
3000 
3001     default:
3002       break;
3003     }
3004   }
3005   return arg_idx;
3006 }
3007 
3008 llvm::Optional<SymbolFile::ArrayInfo>
3009 DWARFASTParser::ParseChildArrayInfo(const DWARFDIE &parent_die,
3010                                     const ExecutionContext *exe_ctx) {
3011   SymbolFile::ArrayInfo array_info;
3012   if (!parent_die)
3013     return llvm::None;
3014 
3015   for (DWARFDIE die : parent_die.children()) {
3016     const dw_tag_t tag = die.Tag();
3017     if (tag != DW_TAG_subrange_type)
3018       continue;
3019 
3020     DWARFAttributes attributes;
3021     const size_t num_child_attributes = die.GetAttributes(attributes);
3022     if (num_child_attributes > 0) {
3023       uint64_t num_elements = 0;
3024       uint64_t lower_bound = 0;
3025       uint64_t upper_bound = 0;
3026       bool upper_bound_valid = false;
3027       uint32_t i;
3028       for (i = 0; i < num_child_attributes; ++i) {
3029         const dw_attr_t attr = attributes.AttributeAtIndex(i);
3030         DWARFFormValue form_value;
3031         if (attributes.ExtractFormValueAtIndex(i, form_value)) {
3032           switch (attr) {
3033           case DW_AT_name:
3034             break;
3035 
3036           case DW_AT_count:
3037             if (DWARFDIE var_die = die.GetReferencedDIE(DW_AT_count)) {
3038               if (var_die.Tag() == DW_TAG_variable)
3039                 if (exe_ctx) {
3040                   if (auto frame = exe_ctx->GetFrameSP()) {
3041                     Status error;
3042                     lldb::VariableSP var_sp;
3043                     auto valobj_sp = frame->GetValueForVariableExpressionPath(
3044                         var_die.GetName(), eNoDynamicValues, 0, var_sp,
3045                         error);
3046                     if (valobj_sp) {
3047                       num_elements = valobj_sp->GetValueAsUnsigned(0);
3048                       break;
3049                     }
3050                   }
3051                 }
3052             } else
3053               num_elements = form_value.Unsigned();
3054             break;
3055 
3056           case DW_AT_bit_stride:
3057             array_info.bit_stride = form_value.Unsigned();
3058             break;
3059 
3060           case DW_AT_byte_stride:
3061             array_info.byte_stride = form_value.Unsigned();
3062             break;
3063 
3064           case DW_AT_lower_bound:
3065             lower_bound = form_value.Unsigned();
3066             break;
3067 
3068           case DW_AT_upper_bound:
3069             upper_bound_valid = true;
3070             upper_bound = form_value.Unsigned();
3071             break;
3072 
3073           default:
3074           case DW_AT_abstract_origin:
3075           case DW_AT_accessibility:
3076           case DW_AT_allocated:
3077           case DW_AT_associated:
3078           case DW_AT_data_location:
3079           case DW_AT_declaration:
3080           case DW_AT_description:
3081           case DW_AT_sibling:
3082           case DW_AT_threads_scaled:
3083           case DW_AT_type:
3084           case DW_AT_visibility:
3085             break;
3086           }
3087         }
3088       }
3089 
3090       if (num_elements == 0) {
3091         if (upper_bound_valid && upper_bound >= lower_bound)
3092           num_elements = upper_bound - lower_bound + 1;
3093       }
3094 
3095       array_info.element_orders.push_back(num_elements);
3096     }
3097   }
3098   return array_info;
3099 }
3100 
3101 Type *DWARFASTParserClang::GetTypeForDIE(const DWARFDIE &die) {
3102   if (die) {
3103     SymbolFileDWARF *dwarf = die.GetDWARF();
3104     DWARFAttributes attributes;
3105     const size_t num_attributes = die.GetAttributes(attributes);
3106     if (num_attributes > 0) {
3107       DWARFFormValue type_die_form;
3108       for (size_t i = 0; i < num_attributes; ++i) {
3109         dw_attr_t attr = attributes.AttributeAtIndex(i);
3110         DWARFFormValue form_value;
3111 
3112         if (attr == DW_AT_type &&
3113             attributes.ExtractFormValueAtIndex(i, form_value))
3114           return dwarf->ResolveTypeUID(form_value.Reference(), true);
3115       }
3116     }
3117   }
3118 
3119   return nullptr;
3120 }
3121 
3122 clang::Decl *DWARFASTParserClang::GetClangDeclForDIE(const DWARFDIE &die) {
3123   if (!die)
3124     return nullptr;
3125 
3126   switch (die.Tag()) {
3127   case DW_TAG_variable:
3128   case DW_TAG_constant:
3129   case DW_TAG_formal_parameter:
3130   case DW_TAG_imported_declaration:
3131   case DW_TAG_imported_module:
3132     break;
3133   default:
3134     return nullptr;
3135   }
3136 
3137   DIEToDeclMap::iterator cache_pos = m_die_to_decl.find(die.GetDIE());
3138   if (cache_pos != m_die_to_decl.end())
3139     return cache_pos->second;
3140 
3141   if (DWARFDIE spec_die = die.GetReferencedDIE(DW_AT_specification)) {
3142     clang::Decl *decl = GetClangDeclForDIE(spec_die);
3143     m_die_to_decl[die.GetDIE()] = decl;
3144     m_decl_to_die[decl].insert(die.GetDIE());
3145     return decl;
3146   }
3147 
3148   if (DWARFDIE abstract_origin_die =
3149           die.GetReferencedDIE(DW_AT_abstract_origin)) {
3150     clang::Decl *decl = GetClangDeclForDIE(abstract_origin_die);
3151     m_die_to_decl[die.GetDIE()] = decl;
3152     m_decl_to_die[decl].insert(die.GetDIE());
3153     return decl;
3154   }
3155 
3156   clang::Decl *decl = nullptr;
3157   switch (die.Tag()) {
3158   case DW_TAG_variable:
3159   case DW_TAG_constant:
3160   case DW_TAG_formal_parameter: {
3161     SymbolFileDWARF *dwarf = die.GetDWARF();
3162     Type *type = GetTypeForDIE(die);
3163     if (dwarf && type) {
3164       const char *name = die.GetName();
3165       clang::DeclContext *decl_context =
3166           TypeSystemClang::DeclContextGetAsDeclContext(
3167               dwarf->GetDeclContextContainingUID(die.GetID()));
3168       decl = m_ast.CreateVariableDeclaration(
3169           decl_context, GetOwningClangModule(die), name,
3170           ClangUtil::GetQualType(type->GetForwardCompilerType()));
3171     }
3172     break;
3173   }
3174   case DW_TAG_imported_declaration: {
3175     SymbolFileDWARF *dwarf = die.GetDWARF();
3176     DWARFDIE imported_uid = die.GetAttributeValueAsReferenceDIE(DW_AT_import);
3177     if (imported_uid) {
3178       CompilerDecl imported_decl = SymbolFileDWARF::GetDecl(imported_uid);
3179       if (imported_decl) {
3180         clang::DeclContext *decl_context =
3181             TypeSystemClang::DeclContextGetAsDeclContext(
3182                 dwarf->GetDeclContextContainingUID(die.GetID()));
3183         if (clang::NamedDecl *clang_imported_decl =
3184                 llvm::dyn_cast<clang::NamedDecl>(
3185                     (clang::Decl *)imported_decl.GetOpaqueDecl()))
3186           decl = m_ast.CreateUsingDeclaration(
3187               decl_context, OptionalClangModuleID(), clang_imported_decl);
3188       }
3189     }
3190     break;
3191   }
3192   case DW_TAG_imported_module: {
3193     SymbolFileDWARF *dwarf = die.GetDWARF();
3194     DWARFDIE imported_uid = die.GetAttributeValueAsReferenceDIE(DW_AT_import);
3195 
3196     if (imported_uid) {
3197       CompilerDeclContext imported_decl_ctx =
3198           SymbolFileDWARF::GetDeclContext(imported_uid);
3199       if (imported_decl_ctx) {
3200         clang::DeclContext *decl_context =
3201             TypeSystemClang::DeclContextGetAsDeclContext(
3202                 dwarf->GetDeclContextContainingUID(die.GetID()));
3203         if (clang::NamespaceDecl *ns_decl =
3204                 TypeSystemClang::DeclContextGetAsNamespaceDecl(
3205                     imported_decl_ctx))
3206           decl = m_ast.CreateUsingDirectiveDeclaration(
3207               decl_context, OptionalClangModuleID(), ns_decl);
3208       }
3209     }
3210     break;
3211   }
3212   default:
3213     break;
3214   }
3215 
3216   m_die_to_decl[die.GetDIE()] = decl;
3217   m_decl_to_die[decl].insert(die.GetDIE());
3218 
3219   return decl;
3220 }
3221 
3222 clang::DeclContext *
3223 DWARFASTParserClang::GetClangDeclContextForDIE(const DWARFDIE &die) {
3224   if (die) {
3225     clang::DeclContext *decl_ctx = GetCachedClangDeclContextForDIE(die);
3226     if (decl_ctx)
3227       return decl_ctx;
3228 
3229     bool try_parsing_type = true;
3230     switch (die.Tag()) {
3231     case DW_TAG_compile_unit:
3232     case DW_TAG_partial_unit:
3233       decl_ctx = m_ast.GetTranslationUnitDecl();
3234       try_parsing_type = false;
3235       break;
3236 
3237     case DW_TAG_namespace:
3238       decl_ctx = ResolveNamespaceDIE(die);
3239       try_parsing_type = false;
3240       break;
3241 
3242     case DW_TAG_lexical_block:
3243       decl_ctx = GetDeclContextForBlock(die);
3244       try_parsing_type = false;
3245       break;
3246 
3247     default:
3248       break;
3249     }
3250 
3251     if (decl_ctx == nullptr && try_parsing_type) {
3252       Type *type = die.GetDWARF()->ResolveType(die);
3253       if (type)
3254         decl_ctx = GetCachedClangDeclContextForDIE(die);
3255     }
3256 
3257     if (decl_ctx) {
3258       LinkDeclContextToDIE(decl_ctx, die);
3259       return decl_ctx;
3260     }
3261   }
3262   return nullptr;
3263 }
3264 
3265 OptionalClangModuleID
3266 DWARFASTParserClang::GetOwningClangModule(const DWARFDIE &die) {
3267   if (!die.IsValid())
3268     return {};
3269 
3270   for (DWARFDIE parent = die.GetParent(); parent.IsValid();
3271        parent = parent.GetParent()) {
3272     const dw_tag_t tag = parent.Tag();
3273     if (tag == DW_TAG_module) {
3274       DWARFDIE module_die = parent;
3275       auto it = m_die_to_module.find(module_die.GetDIE());
3276       if (it != m_die_to_module.end())
3277         return it->second;
3278       const char *name = module_die.GetAttributeValueAsString(DW_AT_name, 0);
3279       if (!name)
3280         return {};
3281 
3282       OptionalClangModuleID id =
3283           m_ast.GetOrCreateClangModule(name, GetOwningClangModule(module_die));
3284       m_die_to_module.insert({module_die.GetDIE(), id});
3285       return id;
3286     }
3287   }
3288   return {};
3289 }
3290 
3291 static bool IsSubroutine(const DWARFDIE &die) {
3292   switch (die.Tag()) {
3293   case DW_TAG_subprogram:
3294   case DW_TAG_inlined_subroutine:
3295     return true;
3296   default:
3297     return false;
3298   }
3299 }
3300 
3301 static DWARFDIE GetContainingFunctionWithAbstractOrigin(const DWARFDIE &die) {
3302   for (DWARFDIE candidate = die; candidate; candidate = candidate.GetParent()) {
3303     if (IsSubroutine(candidate)) {
3304       if (candidate.GetReferencedDIE(DW_AT_abstract_origin)) {
3305         return candidate;
3306       } else {
3307         return DWARFDIE();
3308       }
3309     }
3310   }
3311   assert(0 && "Shouldn't call GetContainingFunctionWithAbstractOrigin on "
3312               "something not in a function");
3313   return DWARFDIE();
3314 }
3315 
3316 static DWARFDIE FindAnyChildWithAbstractOrigin(const DWARFDIE &context) {
3317   for (DWARFDIE candidate : context.children()) {
3318     if (candidate.GetReferencedDIE(DW_AT_abstract_origin)) {
3319       return candidate;
3320     }
3321   }
3322   return DWARFDIE();
3323 }
3324 
3325 static DWARFDIE FindFirstChildWithAbstractOrigin(const DWARFDIE &block,
3326                                                  const DWARFDIE &function) {
3327   assert(IsSubroutine(function));
3328   for (DWARFDIE context = block; context != function.GetParent();
3329        context = context.GetParent()) {
3330     assert(!IsSubroutine(context) || context == function);
3331     if (DWARFDIE child = FindAnyChildWithAbstractOrigin(context)) {
3332       return child;
3333     }
3334   }
3335   return DWARFDIE();
3336 }
3337 
3338 clang::DeclContext *
3339 DWARFASTParserClang::GetDeclContextForBlock(const DWARFDIE &die) {
3340   assert(die.Tag() == DW_TAG_lexical_block);
3341   DWARFDIE containing_function_with_abstract_origin =
3342       GetContainingFunctionWithAbstractOrigin(die);
3343   if (!containing_function_with_abstract_origin) {
3344     return (clang::DeclContext *)ResolveBlockDIE(die);
3345   }
3346   DWARFDIE child = FindFirstChildWithAbstractOrigin(
3347       die, containing_function_with_abstract_origin);
3348   CompilerDeclContext decl_context =
3349       GetDeclContextContainingUIDFromDWARF(child);
3350   return (clang::DeclContext *)decl_context.GetOpaqueDeclContext();
3351 }
3352 
3353 clang::BlockDecl *DWARFASTParserClang::ResolveBlockDIE(const DWARFDIE &die) {
3354   if (die && die.Tag() == DW_TAG_lexical_block) {
3355     clang::BlockDecl *decl =
3356         llvm::cast_or_null<clang::BlockDecl>(m_die_to_decl_ctx[die.GetDIE()]);
3357 
3358     if (!decl) {
3359       DWARFDIE decl_context_die;
3360       clang::DeclContext *decl_context =
3361           GetClangDeclContextContainingDIE(die, &decl_context_die);
3362       decl =
3363           m_ast.CreateBlockDeclaration(decl_context, GetOwningClangModule(die));
3364 
3365       if (decl)
3366         LinkDeclContextToDIE((clang::DeclContext *)decl, die);
3367     }
3368 
3369     return decl;
3370   }
3371   return nullptr;
3372 }
3373 
3374 clang::NamespaceDecl *
3375 DWARFASTParserClang::ResolveNamespaceDIE(const DWARFDIE &die) {
3376   if (die && die.Tag() == DW_TAG_namespace) {
3377     // See if we already parsed this namespace DIE and associated it with a
3378     // uniqued namespace declaration
3379     clang::NamespaceDecl *namespace_decl =
3380         static_cast<clang::NamespaceDecl *>(m_die_to_decl_ctx[die.GetDIE()]);
3381     if (namespace_decl)
3382       return namespace_decl;
3383     else {
3384       const char *namespace_name = die.GetName();
3385       clang::DeclContext *containing_decl_ctx =
3386           GetClangDeclContextContainingDIE(die, nullptr);
3387       bool is_inline =
3388           die.GetAttributeValueAsUnsigned(DW_AT_export_symbols, 0) != 0;
3389 
3390       namespace_decl = m_ast.GetUniqueNamespaceDeclaration(
3391           namespace_name, containing_decl_ctx, GetOwningClangModule(die),
3392           is_inline);
3393       Log *log =
3394           nullptr; // (LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO));
3395       if (log) {
3396         SymbolFileDWARF *dwarf = die.GetDWARF();
3397         if (namespace_name) {
3398           dwarf->GetObjectFile()->GetModule()->LogMessage(
3399               log,
3400               "ASTContext => %p: 0x%8.8" PRIx64
3401               ": DW_TAG_namespace with DW_AT_name(\"%s\") => "
3402               "clang::NamespaceDecl *%p (original = %p)",
3403               static_cast<void *>(&m_ast.getASTContext()), die.GetID(),
3404               namespace_name, static_cast<void *>(namespace_decl),
3405               static_cast<void *>(namespace_decl->getOriginalNamespace()));
3406         } else {
3407           dwarf->GetObjectFile()->GetModule()->LogMessage(
3408               log,
3409               "ASTContext => %p: 0x%8.8" PRIx64
3410               ": DW_TAG_namespace (anonymous) => clang::NamespaceDecl *%p "
3411               "(original = %p)",
3412               static_cast<void *>(&m_ast.getASTContext()), die.GetID(),
3413               static_cast<void *>(namespace_decl),
3414               static_cast<void *>(namespace_decl->getOriginalNamespace()));
3415         }
3416       }
3417 
3418       if (namespace_decl)
3419         LinkDeclContextToDIE((clang::DeclContext *)namespace_decl, die);
3420       return namespace_decl;
3421     }
3422   }
3423   return nullptr;
3424 }
3425 
3426 clang::DeclContext *DWARFASTParserClang::GetClangDeclContextContainingDIE(
3427     const DWARFDIE &die, DWARFDIE *decl_ctx_die_copy) {
3428   SymbolFileDWARF *dwarf = die.GetDWARF();
3429 
3430   DWARFDIE decl_ctx_die = dwarf->GetDeclContextDIEContainingDIE(die);
3431 
3432   if (decl_ctx_die_copy)
3433     *decl_ctx_die_copy = decl_ctx_die;
3434 
3435   if (decl_ctx_die) {
3436     clang::DeclContext *clang_decl_ctx =
3437         GetClangDeclContextForDIE(decl_ctx_die);
3438     if (clang_decl_ctx)
3439       return clang_decl_ctx;
3440   }
3441   return m_ast.GetTranslationUnitDecl();
3442 }
3443 
3444 clang::DeclContext *
3445 DWARFASTParserClang::GetCachedClangDeclContextForDIE(const DWARFDIE &die) {
3446   if (die) {
3447     DIEToDeclContextMap::iterator pos = m_die_to_decl_ctx.find(die.GetDIE());
3448     if (pos != m_die_to_decl_ctx.end())
3449       return pos->second;
3450   }
3451   return nullptr;
3452 }
3453 
3454 void DWARFASTParserClang::LinkDeclContextToDIE(clang::DeclContext *decl_ctx,
3455                                                const DWARFDIE &die) {
3456   m_die_to_decl_ctx[die.GetDIE()] = decl_ctx;
3457   // There can be many DIEs for a single decl context
3458   // m_decl_ctx_to_die[decl_ctx].insert(die.GetDIE());
3459   m_decl_ctx_to_die.insert(std::make_pair(decl_ctx, die));
3460 }
3461 
3462 bool DWARFASTParserClang::CopyUniqueClassMethodTypes(
3463     const DWARFDIE &src_class_die, const DWARFDIE &dst_class_die,
3464     lldb_private::Type *class_type, std::vector<DWARFDIE> &failures) {
3465   if (!class_type || !src_class_die || !dst_class_die)
3466     return false;
3467   if (src_class_die.Tag() != dst_class_die.Tag())
3468     return false;
3469 
3470   // We need to complete the class type so we can get all of the method types
3471   // parsed so we can then unique those types to their equivalent counterparts
3472   // in "dst_cu" and "dst_class_die"
3473   class_type->GetFullCompilerType();
3474 
3475   DWARFDIE src_die;
3476   DWARFDIE dst_die;
3477   UniqueCStringMap<DWARFDIE> src_name_to_die;
3478   UniqueCStringMap<DWARFDIE> dst_name_to_die;
3479   UniqueCStringMap<DWARFDIE> src_name_to_die_artificial;
3480   UniqueCStringMap<DWARFDIE> dst_name_to_die_artificial;
3481   for (src_die = src_class_die.GetFirstChild(); src_die.IsValid();
3482        src_die = src_die.GetSibling()) {
3483     if (src_die.Tag() == DW_TAG_subprogram) {
3484       // Make sure this is a declaration and not a concrete instance by looking
3485       // for DW_AT_declaration set to 1. Sometimes concrete function instances
3486       // are placed inside the class definitions and shouldn't be included in
3487       // the list of things are are tracking here.
3488       if (src_die.GetAttributeValueAsUnsigned(DW_AT_declaration, 0) == 1) {
3489         const char *src_name = src_die.GetMangledName();
3490         if (src_name) {
3491           ConstString src_const_name(src_name);
3492           if (src_die.GetAttributeValueAsUnsigned(DW_AT_artificial, 0))
3493             src_name_to_die_artificial.Append(src_const_name, src_die);
3494           else
3495             src_name_to_die.Append(src_const_name, src_die);
3496         }
3497       }
3498     }
3499   }
3500   for (dst_die = dst_class_die.GetFirstChild(); dst_die.IsValid();
3501        dst_die = dst_die.GetSibling()) {
3502     if (dst_die.Tag() == DW_TAG_subprogram) {
3503       // Make sure this is a declaration and not a concrete instance by looking
3504       // for DW_AT_declaration set to 1. Sometimes concrete function instances
3505       // are placed inside the class definitions and shouldn't be included in
3506       // the list of things are are tracking here.
3507       if (dst_die.GetAttributeValueAsUnsigned(DW_AT_declaration, 0) == 1) {
3508         const char *dst_name = dst_die.GetMangledName();
3509         if (dst_name) {
3510           ConstString dst_const_name(dst_name);
3511           if (dst_die.GetAttributeValueAsUnsigned(DW_AT_artificial, 0))
3512             dst_name_to_die_artificial.Append(dst_const_name, dst_die);
3513           else
3514             dst_name_to_die.Append(dst_const_name, dst_die);
3515         }
3516       }
3517     }
3518   }
3519   const uint32_t src_size = src_name_to_die.GetSize();
3520   const uint32_t dst_size = dst_name_to_die.GetSize();
3521   Log *log = nullptr; // (LogChannelDWARF::GetLogIfAny(DWARF_LOG_DEBUG_INFO |
3522                       // DWARF_LOG_TYPE_COMPLETION));
3523 
3524   // Is everything kosher so we can go through the members at top speed?
3525   bool fast_path = true;
3526 
3527   if (src_size != dst_size) {
3528     if (src_size != 0 && dst_size != 0) {
3529       LLDB_LOGF(log,
3530                 "warning: trying to unique class DIE 0x%8.8x to 0x%8.8x, "
3531                 "but they didn't have the same size (src=%d, dst=%d)",
3532                 src_class_die.GetOffset(), dst_class_die.GetOffset(), src_size,
3533                 dst_size);
3534     }
3535 
3536     fast_path = false;
3537   }
3538 
3539   uint32_t idx;
3540 
3541   if (fast_path) {
3542     for (idx = 0; idx < src_size; ++idx) {
3543       src_die = src_name_to_die.GetValueAtIndexUnchecked(idx);
3544       dst_die = dst_name_to_die.GetValueAtIndexUnchecked(idx);
3545 
3546       if (src_die.Tag() != dst_die.Tag()) {
3547         LLDB_LOGF(log,
3548                   "warning: tried to unique class DIE 0x%8.8x to 0x%8.8x, "
3549                   "but 0x%8.8x (%s) tags didn't match 0x%8.8x (%s)",
3550                   src_class_die.GetOffset(), dst_class_die.GetOffset(),
3551                   src_die.GetOffset(), src_die.GetTagAsCString(),
3552                   dst_die.GetOffset(), dst_die.GetTagAsCString());
3553         fast_path = false;
3554       }
3555 
3556       const char *src_name = src_die.GetMangledName();
3557       const char *dst_name = dst_die.GetMangledName();
3558 
3559       // Make sure the names match
3560       if (src_name == dst_name || (strcmp(src_name, dst_name) == 0))
3561         continue;
3562 
3563       LLDB_LOGF(log,
3564                 "warning: tried to unique class DIE 0x%8.8x to 0x%8.8x, "
3565                 "but 0x%8.8x (%s) names didn't match 0x%8.8x (%s)",
3566                 src_class_die.GetOffset(), dst_class_die.GetOffset(),
3567                 src_die.GetOffset(), src_name, dst_die.GetOffset(), dst_name);
3568 
3569       fast_path = false;
3570     }
3571   }
3572 
3573   DWARFASTParserClang *src_dwarf_ast_parser =
3574       static_cast<DWARFASTParserClang *>(
3575           SymbolFileDWARF::GetDWARFParser(*src_die.GetCU()));
3576   DWARFASTParserClang *dst_dwarf_ast_parser =
3577       static_cast<DWARFASTParserClang *>(
3578           SymbolFileDWARF::GetDWARFParser(*dst_die.GetCU()));
3579 
3580   // Now do the work of linking the DeclContexts and Types.
3581   if (fast_path) {
3582     // We can do this quickly.  Just run across the tables index-for-index
3583     // since we know each node has matching names and tags.
3584     for (idx = 0; idx < src_size; ++idx) {
3585       src_die = src_name_to_die.GetValueAtIndexUnchecked(idx);
3586       dst_die = dst_name_to_die.GetValueAtIndexUnchecked(idx);
3587 
3588       clang::DeclContext *src_decl_ctx =
3589           src_dwarf_ast_parser->m_die_to_decl_ctx[src_die.GetDIE()];
3590       if (src_decl_ctx) {
3591         LLDB_LOGF(log, "uniquing decl context %p from 0x%8.8x for 0x%8.8x",
3592                   static_cast<void *>(src_decl_ctx), src_die.GetOffset(),
3593                   dst_die.GetOffset());
3594         dst_dwarf_ast_parser->LinkDeclContextToDIE(src_decl_ctx, dst_die);
3595       } else {
3596         LLDB_LOGF(log,
3597                   "warning: tried to unique decl context from 0x%8.8x for "
3598                   "0x%8.8x, but none was found",
3599                   src_die.GetOffset(), dst_die.GetOffset());
3600       }
3601 
3602       Type *src_child_type =
3603           dst_die.GetDWARF()->GetDIEToType()[src_die.GetDIE()];
3604       if (src_child_type) {
3605         LLDB_LOGF(log,
3606                   "uniquing type %p (uid=0x%" PRIx64
3607                   ") from 0x%8.8x for 0x%8.8x",
3608                   static_cast<void *>(src_child_type), src_child_type->GetID(),
3609                   src_die.GetOffset(), dst_die.GetOffset());
3610         dst_die.GetDWARF()->GetDIEToType()[dst_die.GetDIE()] = src_child_type;
3611       } else {
3612         LLDB_LOGF(log,
3613                   "warning: tried to unique lldb_private::Type from "
3614                   "0x%8.8x for 0x%8.8x, but none was found",
3615                   src_die.GetOffset(), dst_die.GetOffset());
3616       }
3617     }
3618   } else {
3619     // We must do this slowly.  For each member of the destination, look up a
3620     // member in the source with the same name, check its tag, and unique them
3621     // if everything matches up.  Report failures.
3622 
3623     if (!src_name_to_die.IsEmpty() && !dst_name_to_die.IsEmpty()) {
3624       src_name_to_die.Sort();
3625 
3626       for (idx = 0; idx < dst_size; ++idx) {
3627         ConstString dst_name = dst_name_to_die.GetCStringAtIndex(idx);
3628         dst_die = dst_name_to_die.GetValueAtIndexUnchecked(idx);
3629         src_die = src_name_to_die.Find(dst_name, DWARFDIE());
3630 
3631         if (src_die && (src_die.Tag() == dst_die.Tag())) {
3632           clang::DeclContext *src_decl_ctx =
3633               src_dwarf_ast_parser->m_die_to_decl_ctx[src_die.GetDIE()];
3634           if (src_decl_ctx) {
3635             LLDB_LOGF(log, "uniquing decl context %p from 0x%8.8x for 0x%8.8x",
3636                       static_cast<void *>(src_decl_ctx), src_die.GetOffset(),
3637                       dst_die.GetOffset());
3638             dst_dwarf_ast_parser->LinkDeclContextToDIE(src_decl_ctx, dst_die);
3639           } else {
3640             LLDB_LOGF(log,
3641                       "warning: tried to unique decl context from 0x%8.8x "
3642                       "for 0x%8.8x, but none was found",
3643                       src_die.GetOffset(), dst_die.GetOffset());
3644           }
3645 
3646           Type *src_child_type =
3647               dst_die.GetDWARF()->GetDIEToType()[src_die.GetDIE()];
3648           if (src_child_type) {
3649             LLDB_LOGF(
3650                 log,
3651                 "uniquing type %p (uid=0x%" PRIx64 ") from 0x%8.8x for 0x%8.8x",
3652                 static_cast<void *>(src_child_type), src_child_type->GetID(),
3653                 src_die.GetOffset(), dst_die.GetOffset());
3654             dst_die.GetDWARF()->GetDIEToType()[dst_die.GetDIE()] =
3655                 src_child_type;
3656           } else {
3657             LLDB_LOGF(log,
3658                       "warning: tried to unique lldb_private::Type from "
3659                       "0x%8.8x for 0x%8.8x, but none was found",
3660                       src_die.GetOffset(), dst_die.GetOffset());
3661           }
3662         } else {
3663           LLDB_LOGF(log, "warning: couldn't find a match for 0x%8.8x",
3664                     dst_die.GetOffset());
3665 
3666           failures.push_back(dst_die);
3667         }
3668       }
3669     }
3670   }
3671 
3672   const uint32_t src_size_artificial = src_name_to_die_artificial.GetSize();
3673   const uint32_t dst_size_artificial = dst_name_to_die_artificial.GetSize();
3674 
3675   if (src_size_artificial && dst_size_artificial) {
3676     dst_name_to_die_artificial.Sort();
3677 
3678     for (idx = 0; idx < src_size_artificial; ++idx) {
3679       ConstString src_name_artificial =
3680           src_name_to_die_artificial.GetCStringAtIndex(idx);
3681       src_die = src_name_to_die_artificial.GetValueAtIndexUnchecked(idx);
3682       dst_die =
3683           dst_name_to_die_artificial.Find(src_name_artificial, DWARFDIE());
3684 
3685       if (dst_die) {
3686         // Both classes have the artificial types, link them
3687         clang::DeclContext *src_decl_ctx =
3688             src_dwarf_ast_parser->m_die_to_decl_ctx[src_die.GetDIE()];
3689         if (src_decl_ctx) {
3690           LLDB_LOGF(log, "uniquing decl context %p from 0x%8.8x for 0x%8.8x",
3691                     static_cast<void *>(src_decl_ctx), src_die.GetOffset(),
3692                     dst_die.GetOffset());
3693           dst_dwarf_ast_parser->LinkDeclContextToDIE(src_decl_ctx, dst_die);
3694         } else {
3695           LLDB_LOGF(log,
3696                     "warning: tried to unique decl context from 0x%8.8x "
3697                     "for 0x%8.8x, but none was found",
3698                     src_die.GetOffset(), dst_die.GetOffset());
3699         }
3700 
3701         Type *src_child_type =
3702             dst_die.GetDWARF()->GetDIEToType()[src_die.GetDIE()];
3703         if (src_child_type) {
3704           LLDB_LOGF(
3705               log,
3706               "uniquing type %p (uid=0x%" PRIx64 ") from 0x%8.8x for 0x%8.8x",
3707               static_cast<void *>(src_child_type), src_child_type->GetID(),
3708               src_die.GetOffset(), dst_die.GetOffset());
3709           dst_die.GetDWARF()->GetDIEToType()[dst_die.GetDIE()] = src_child_type;
3710         } else {
3711           LLDB_LOGF(log,
3712                     "warning: tried to unique lldb_private::Type from "
3713                     "0x%8.8x for 0x%8.8x, but none was found",
3714                     src_die.GetOffset(), dst_die.GetOffset());
3715         }
3716       }
3717     }
3718   }
3719 
3720   if (dst_size_artificial) {
3721     for (idx = 0; idx < dst_size_artificial; ++idx) {
3722       ConstString dst_name_artificial =
3723           dst_name_to_die_artificial.GetCStringAtIndex(idx);
3724       dst_die = dst_name_to_die_artificial.GetValueAtIndexUnchecked(idx);
3725       LLDB_LOGF(log,
3726                 "warning: need to create artificial method for 0x%8.8x for "
3727                 "method '%s'",
3728                 dst_die.GetOffset(), dst_name_artificial.GetCString());
3729 
3730       failures.push_back(dst_die);
3731     }
3732   }
3733 
3734   return !failures.empty();
3735 }
3736