1 //===-- DWARFASTParserClang.cpp ---------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include <stdlib.h>
11 
12 #include "DWARFASTParserClang.h"
13 #include "DWARFDIE.h"
14 #include "DWARFDIECollection.h"
15 #include "DWARFDebugInfo.h"
16 #include "DWARFDeclContext.h"
17 #include "DWARFDefines.h"
18 #include "SymbolFileDWARF.h"
19 #include "SymbolFileDWARFDwo.h"
20 #include "SymbolFileDWARFDebugMap.h"
21 #include "UniqueDWARFASTType.h"
22 
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/ClangASTImporter.h"
28 #include "lldb/Symbol/ClangExternalASTSourceCommon.h"
29 #include "lldb/Symbol/ClangUtil.h"
30 #include "lldb/Symbol/CompileUnit.h"
31 #include "lldb/Symbol/Function.h"
32 #include "lldb/Symbol/ObjectFile.h"
33 #include "lldb/Symbol/SymbolVendor.h"
34 #include "lldb/Symbol/TypeList.h"
35 #include "lldb/Symbol/TypeMap.h"
36 #include "lldb/Target/Language.h"
37 #include "lldb/Utility/LLDBAssert.h"
38 #include "lldb/Utility/Log.h"
39 #include "lldb/Utility/StreamString.h"
40 
41 #include "clang/AST/CXXInheritance.h"
42 #include "clang/AST/DeclCXX.h"
43 #include "clang/AST/DeclObjC.h"
44 #include "clang/AST/DeclTemplate.h"
45 
46 #include <map>
47 #include <vector>
48 
49 //#define ENABLE_DEBUG_PRINTF // COMMENT OUT THIS LINE PRIOR TO CHECKIN
50 
51 #ifdef ENABLE_DEBUG_PRINTF
52 #include <stdio.h>
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(ClangASTContext &ast)
61     : m_ast(ast), m_die_to_decl_ctx(), m_decl_ctx_to_die() {}
62 
63 DWARFASTParserClang::~DWARFASTParserClang() {}
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 struct BitfieldInfo {
91   uint64_t bit_size;
92   uint64_t bit_offset;
93 
94   BitfieldInfo()
95       : bit_size(LLDB_INVALID_ADDRESS), bit_offset(LLDB_INVALID_ADDRESS) {}
96 
97   void Clear() {
98     bit_size = LLDB_INVALID_ADDRESS;
99     bit_offset = LLDB_INVALID_ADDRESS;
100   }
101 
102   bool IsValid() const {
103     return (bit_size != LLDB_INVALID_ADDRESS) &&
104            (bit_offset != LLDB_INVALID_ADDRESS);
105   }
106 
107   bool NextBitfieldOffsetIsValid(const uint64_t next_bit_offset) const {
108     if (IsValid()) {
109       // This bitfield info is valid, so any subsequent bitfields must not
110       // overlap and must be at a higher bit offset than any previous bitfield
111       // + size.
112       return (bit_size + bit_offset) <= next_bit_offset;
113     } else {
114       // If the this BitfieldInfo is not valid, then any offset isOK
115       return true;
116     }
117   }
118 };
119 
120 ClangASTImporter &DWARFASTParserClang::GetClangASTImporter() {
121   if (!m_clang_ast_importer_ap) {
122     m_clang_ast_importer_ap.reset(new ClangASTImporter);
123   }
124   return *m_clang_ast_importer_ap;
125 }
126 
127 /// Detect a forward declaration that is nested in a DW_TAG_module.
128 static bool isClangModuleFwdDecl(const DWARFDIE &Die) {
129   if (!Die.GetAttributeValueAsUnsigned(DW_AT_declaration, 0))
130     return false;
131   auto Parent = Die.GetParent();
132   while (Parent.IsValid()) {
133     if (Parent.Tag() == DW_TAG_module)
134       return true;
135     Parent = Parent.GetParent();
136   }
137   return false;
138 }
139 
140 TypeSP DWARFASTParserClang::ParseTypeFromDWO(const DWARFDIE &die, Log *log) {
141   ModuleSP dwo_module_sp = die.GetContainingDWOModule();
142   if (!dwo_module_sp)
143     return TypeSP();
144 
145   // This type comes from an external DWO module.
146   std::vector<CompilerContext> dwo_context;
147   die.GetDWOContext(dwo_context);
148   TypeMap dwo_types;
149 
150   if (!dwo_module_sp->GetSymbolVendor()->FindTypes(dwo_context, true,
151                                                    dwo_types)) {
152     if (!isClangModuleFwdDecl(die))
153       return TypeSP();
154 
155     // Since this this type is defined in one of the Clang modules imported by
156     // this symbol file, search all of them.
157     auto *SymFile = die.GetCU()->GetSymbolFileDWARF();
158     for (const auto &NameModule : SymFile->getExternalTypeModules()) {
159       if (!NameModule.second)
160         continue;
161       SymbolVendor *SymVendor = NameModule.second->GetSymbolVendor();
162       if (SymVendor->FindTypes(dwo_context, true, dwo_types))
163         break;
164     }
165   }
166 
167   const size_t num_dwo_types = dwo_types.GetSize();
168   if (num_dwo_types != 1)
169     return TypeSP();
170 
171   // We found a real definition for this type in the Clang module, so lets use
172   // it and cache the fact that we found a complete type for this die.
173   TypeSP dwo_type_sp = dwo_types.GetTypeAtIndex(0);
174   if (!dwo_type_sp)
175     return TypeSP();
176 
177   lldb_private::CompilerType dwo_type = dwo_type_sp->GetForwardCompilerType();
178 
179   lldb_private::CompilerType type =
180       GetClangASTImporter().CopyType(m_ast, dwo_type);
181 
182   if (!type)
183     return TypeSP();
184 
185   SymbolFileDWARF *dwarf = die.GetDWARF();
186   TypeSP type_sp(new Type(
187       die.GetID(), dwarf, dwo_type_sp->GetName(), dwo_type_sp->GetByteSize(),
188       NULL, LLDB_INVALID_UID, Type::eEncodingInvalid,
189       &dwo_type_sp->GetDeclaration(), type, Type::eResolveStateForward));
190 
191   dwarf->GetTypeList()->Insert(type_sp);
192   dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
193   clang::TagDecl *tag_decl = ClangASTContext::GetAsTagDecl(type);
194   if (tag_decl)
195     LinkDeclContextToDIE(tag_decl, die);
196   else {
197     clang::DeclContext *defn_decl_ctx = GetCachedClangDeclContextForDIE(die);
198     if (defn_decl_ctx)
199       LinkDeclContextToDIE(defn_decl_ctx, die);
200   }
201 
202   return type_sp;
203 }
204 
205 static void CompleteExternalTagDeclType(ClangASTImporter &ast_importer,
206                                         clang::DeclContext *decl_ctx,
207                                         DWARFDIE die,
208                                         const char *type_name_cstr) {
209   auto *tag_decl_ctx = clang::dyn_cast<clang::TagDecl>(decl_ctx);
210   if (!tag_decl_ctx)
211     return;
212 
213   // If this type was not imported from an external AST, there's nothing to do.
214   CompilerType type = ClangASTContext::GetTypeForDecl(tag_decl_ctx);
215   if (!type || !ast_importer.CanImport(type))
216     return;
217 
218   auto qual_type = ClangUtil::GetQualType(type);
219   if (!ast_importer.RequireCompleteType(qual_type)) {
220     die.GetDWARF()->GetObjectFile()->GetModule()->ReportError(
221         "Unable to complete the Decl context for DIE '%s' at offset "
222         "0x%8.8x.\nPlease file a bug report.",
223         type_name_cstr ? type_name_cstr : "", die.GetOffset());
224     // We need to make the type look complete otherwise, we might crash in
225     // Clang when adding children.
226     if (ClangASTContext::StartTagDeclarationDefinition(type))
227       ClangASTContext::CompleteTagDeclarationDefinition(type);
228   }
229 }
230 
231 TypeSP DWARFASTParserClang::ParseTypeFromDWARF(const SymbolContext &sc,
232                                                const DWARFDIE &die, Log *log,
233                                                bool *type_is_new_ptr) {
234   TypeSP type_sp;
235 
236   if (type_is_new_ptr)
237     *type_is_new_ptr = false;
238 
239   AccessType accessibility = eAccessNone;
240   if (die) {
241     SymbolFileDWARF *dwarf = die.GetDWARF();
242     if (log) {
243       DWARFDIE context_die;
244       clang::DeclContext *context =
245           GetClangDeclContextContainingDIE(die, &context_die);
246 
247       dwarf->GetObjectFile()->GetModule()->LogMessage(
248           log, "SymbolFileDWARF::ParseType (die = 0x%8.8x, decl_ctx = %p (die "
249                "0x%8.8x)) %s name = '%s')",
250           die.GetOffset(), static_cast<void *>(context),
251           context_die.GetOffset(), die.GetTagAsCString(), die.GetName());
252     }
253     Type *type_ptr = dwarf->GetDIEToType().lookup(die.GetDIE());
254     TypeList *type_list = dwarf->GetTypeList();
255     if (type_ptr == NULL) {
256       if (type_is_new_ptr)
257         *type_is_new_ptr = true;
258 
259       const dw_tag_t tag = die.Tag();
260 
261       bool is_forward_declaration = false;
262       DWARFAttributes attributes;
263       const char *type_name_cstr = NULL;
264       const char *mangled_name_cstr = NULL;
265       ConstString type_name_const_str;
266       Type::ResolveState resolve_state = Type::eResolveStateUnresolved;
267       uint64_t byte_size = 0;
268       Declaration decl;
269 
270       Type::EncodingDataType encoding_data_type = Type::eEncodingIsUID;
271       CompilerType clang_type;
272       DWARFFormValue form_value;
273 
274       dw_attr_t attr;
275 
276       switch (tag) {
277       case DW_TAG_typedef:
278       case DW_TAG_base_type:
279       case DW_TAG_pointer_type:
280       case DW_TAG_reference_type:
281       case DW_TAG_rvalue_reference_type:
282       case DW_TAG_const_type:
283       case DW_TAG_restrict_type:
284       case DW_TAG_volatile_type:
285       case DW_TAG_unspecified_type: {
286         // Set a bit that lets us know that we are currently parsing this
287         dwarf->GetDIEToType()[die.GetDIE()] = DIE_IS_BEING_PARSED;
288 
289         const size_t num_attributes = die.GetAttributes(attributes);
290         uint32_t encoding = 0;
291         DWARFFormValue encoding_uid;
292 
293         if (num_attributes > 0) {
294           uint32_t i;
295           for (i = 0; i < num_attributes; ++i) {
296             attr = attributes.AttributeAtIndex(i);
297             if (attributes.ExtractFormValueAtIndex(i, form_value)) {
298               switch (attr) {
299               case DW_AT_decl_file:
300                 decl.SetFile(sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(
301                     form_value.Unsigned()));
302                 break;
303               case DW_AT_decl_line:
304                 decl.SetLine(form_value.Unsigned());
305                 break;
306               case DW_AT_decl_column:
307                 decl.SetColumn(form_value.Unsigned());
308                 break;
309               case DW_AT_name:
310                 type_name_cstr = form_value.AsCString();
311                 if (type_name_cstr)
312                   type_name_const_str.SetCString(type_name_cstr);
313                 break;
314               case DW_AT_byte_size:
315                 byte_size = form_value.Unsigned();
316                 break;
317               case DW_AT_encoding:
318                 encoding = form_value.Unsigned();
319                 break;
320               case DW_AT_type:
321                 encoding_uid = form_value;
322                 break;
323               default:
324               case DW_AT_sibling:
325                 break;
326               }
327             }
328           }
329         }
330 
331         if (tag == DW_TAG_typedef && encoding_uid.IsValid()) {
332           // Try to parse a typedef from the DWO file first as modules can
333           // contain typedef'ed structures that have no names like:
334           //
335           //  typedef struct { int a; } Foo;
336           //
337           // In this case we will have a structure with no name and a typedef
338           // named "Foo" that points to this unnamed structure. The name in the
339           // typedef is the only identifier for the struct, so always try to
340           // get typedefs from DWO files if possible.
341           //
342           // The type_sp returned will be empty if the typedef doesn't exist in
343           // a DWO file, so it is cheap to call this function just to check.
344           //
345           // If we don't do this we end up creating a TypeSP that says this is
346           // a typedef to type 0x123 (the DW_AT_type value would be 0x123 in
347           // the DW_TAG_typedef), and this is the unnamed structure type. We
348           // will have a hard time tracking down an unnammed structure type in
349           // the module DWO file, so we make sure we don't get into this
350           // situation by always resolving typedefs from the DWO file.
351           const DWARFDIE encoding_die = dwarf->GetDIE(DIERef(encoding_uid));
352 
353           // First make sure that the die that this is typedef'ed to _is_ just
354           // a declaration (DW_AT_declaration == 1), not a full definition
355           // since template types can't be represented in modules since only
356           // concrete instances of templates are ever emitted and modules won't
357           // contain those
358           if (encoding_die &&
359               encoding_die.GetAttributeValueAsUnsigned(DW_AT_declaration, 0) ==
360                   1) {
361             type_sp = ParseTypeFromDWO(die, log);
362             if (type_sp)
363               return type_sp;
364           }
365         }
366 
367         DEBUG_PRINTF("0x%8.8" PRIx64 ": %s (\"%s\") type => 0x%8.8lx\n",
368                      die.GetID(), DW_TAG_value_to_name(tag), type_name_cstr,
369                      encoding_uid.Reference());
370 
371         switch (tag) {
372         default:
373           break;
374 
375         case DW_TAG_unspecified_type:
376           if (strcmp(type_name_cstr, "nullptr_t") == 0 ||
377               strcmp(type_name_cstr, "decltype(nullptr)") == 0) {
378             resolve_state = Type::eResolveStateFull;
379             clang_type = m_ast.GetBasicType(eBasicTypeNullPtr);
380             break;
381           }
382           // Fall through to base type below in case we can handle the type
383           // there...
384           LLVM_FALLTHROUGH;
385 
386         case DW_TAG_base_type:
387           resolve_state = Type::eResolveStateFull;
388           clang_type = m_ast.GetBuiltinTypeForDWARFEncodingAndBitSize(
389               type_name_cstr, encoding, byte_size * 8);
390           break;
391 
392         case DW_TAG_pointer_type:
393           encoding_data_type = Type::eEncodingIsPointerUID;
394           break;
395         case DW_TAG_reference_type:
396           encoding_data_type = Type::eEncodingIsLValueReferenceUID;
397           break;
398         case DW_TAG_rvalue_reference_type:
399           encoding_data_type = Type::eEncodingIsRValueReferenceUID;
400           break;
401         case DW_TAG_typedef:
402           encoding_data_type = Type::eEncodingIsTypedefUID;
403           break;
404         case DW_TAG_const_type:
405           encoding_data_type = Type::eEncodingIsConstUID;
406           break;
407         case DW_TAG_restrict_type:
408           encoding_data_type = Type::eEncodingIsRestrictUID;
409           break;
410         case DW_TAG_volatile_type:
411           encoding_data_type = Type::eEncodingIsVolatileUID;
412           break;
413         }
414 
415         if (!clang_type &&
416             (encoding_data_type == Type::eEncodingIsPointerUID ||
417              encoding_data_type == Type::eEncodingIsTypedefUID) &&
418             sc.comp_unit != NULL) {
419           if (tag == DW_TAG_pointer_type) {
420             DWARFDIE target_die = die.GetReferencedDIE(DW_AT_type);
421 
422             if (target_die.GetAttributeValueAsUnsigned(DW_AT_APPLE_block, 0)) {
423               // Blocks have a __FuncPtr inside them which is a pointer to a
424               // function of the proper type.
425 
426               for (DWARFDIE child_die = target_die.GetFirstChild();
427                    child_die.IsValid(); child_die = child_die.GetSibling()) {
428                 if (!strcmp(child_die.GetAttributeValueAsString(DW_AT_name, ""),
429                             "__FuncPtr")) {
430                   DWARFDIE function_pointer_type =
431                       child_die.GetReferencedDIE(DW_AT_type);
432 
433                   if (function_pointer_type) {
434                     DWARFDIE function_type =
435                         function_pointer_type.GetReferencedDIE(DW_AT_type);
436 
437                     bool function_type_is_new_pointer;
438                     TypeSP lldb_function_type_sp = ParseTypeFromDWARF(
439                         sc, function_type, log, &function_type_is_new_pointer);
440 
441                     if (lldb_function_type_sp) {
442                       clang_type = m_ast.CreateBlockPointerType(
443                           lldb_function_type_sp->GetForwardCompilerType());
444                       encoding_data_type = Type::eEncodingIsUID;
445                       encoding_uid.Clear();
446                       resolve_state = Type::eResolveStateFull;
447                     }
448                   }
449 
450                   break;
451                 }
452               }
453             }
454           }
455 
456           bool translation_unit_is_objc =
457               (sc.comp_unit->GetLanguage() == eLanguageTypeObjC ||
458                sc.comp_unit->GetLanguage() == eLanguageTypeObjC_plus_plus);
459 
460           if (translation_unit_is_objc) {
461             if (type_name_cstr != NULL) {
462               static ConstString g_objc_type_name_id("id");
463               static ConstString g_objc_type_name_Class("Class");
464               static ConstString g_objc_type_name_selector("SEL");
465 
466               if (type_name_const_str == g_objc_type_name_id) {
467                 if (log)
468                   dwarf->GetObjectFile()->GetModule()->LogMessage(
469                       log, "SymbolFileDWARF::ParseType (die = 0x%8.8x) %s '%s' "
470                            "is Objective-C 'id' built-in type.",
471                       die.GetOffset(), die.GetTagAsCString(), die.GetName());
472                 clang_type = m_ast.GetBasicType(eBasicTypeObjCID);
473                 encoding_data_type = Type::eEncodingIsUID;
474                 encoding_uid.Clear();
475                 resolve_state = Type::eResolveStateFull;
476 
477               } else if (type_name_const_str == g_objc_type_name_Class) {
478                 if (log)
479                   dwarf->GetObjectFile()->GetModule()->LogMessage(
480                       log, "SymbolFileDWARF::ParseType (die = 0x%8.8x) %s '%s' "
481                            "is Objective-C 'Class' built-in type.",
482                       die.GetOffset(), die.GetTagAsCString(), die.GetName());
483                 clang_type = m_ast.GetBasicType(eBasicTypeObjCClass);
484                 encoding_data_type = Type::eEncodingIsUID;
485                 encoding_uid.Clear();
486                 resolve_state = Type::eResolveStateFull;
487               } else if (type_name_const_str == g_objc_type_name_selector) {
488                 if (log)
489                   dwarf->GetObjectFile()->GetModule()->LogMessage(
490                       log, "SymbolFileDWARF::ParseType (die = 0x%8.8x) %s '%s' "
491                            "is Objective-C 'selector' built-in type.",
492                       die.GetOffset(), die.GetTagAsCString(), die.GetName());
493                 clang_type = m_ast.GetBasicType(eBasicTypeObjCSel);
494                 encoding_data_type = Type::eEncodingIsUID;
495                 encoding_uid.Clear();
496                 resolve_state = Type::eResolveStateFull;
497               }
498             } else if (encoding_data_type == Type::eEncodingIsPointerUID &&
499                        encoding_uid.IsValid()) {
500               // Clang sometimes erroneously emits id as objc_object*.  In that
501               // case we fix up the type to "id".
502 
503               const DWARFDIE encoding_die = dwarf->GetDIE(DIERef(encoding_uid));
504 
505               if (encoding_die && encoding_die.Tag() == DW_TAG_structure_type) {
506                 if (const char *struct_name = encoding_die.GetName()) {
507                   if (!strcmp(struct_name, "objc_object")) {
508                     if (log)
509                       dwarf->GetObjectFile()->GetModule()->LogMessage(
510                           log, "SymbolFileDWARF::ParseType (die = 0x%8.8x) %s "
511                                "'%s' is 'objc_object*', which we overrode to "
512                                "'id'.",
513                           die.GetOffset(), die.GetTagAsCString(),
514                           die.GetName());
515                     clang_type = m_ast.GetBasicType(eBasicTypeObjCID);
516                     encoding_data_type = Type::eEncodingIsUID;
517                     encoding_uid.Clear();
518                     resolve_state = Type::eResolveStateFull;
519                   }
520                 }
521               }
522             }
523           }
524         }
525 
526         type_sp.reset(
527             new Type(die.GetID(), dwarf, type_name_const_str, byte_size, NULL,
528                      DIERef(encoding_uid).GetUID(dwarf), encoding_data_type,
529                      &decl, clang_type, resolve_state));
530 
531         dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
532       } break;
533 
534       case DW_TAG_structure_type:
535       case DW_TAG_union_type:
536       case DW_TAG_class_type: {
537         // Set a bit that lets us know that we are currently parsing this
538         dwarf->GetDIEToType()[die.GetDIE()] = DIE_IS_BEING_PARSED;
539         bool byte_size_valid = false;
540 
541         LanguageType class_language = eLanguageTypeUnknown;
542         bool is_complete_objc_class = false;
543         size_t calling_convention
544                 = llvm::dwarf::CallingConvention::DW_CC_normal;
545 
546         const size_t num_attributes = die.GetAttributes(attributes);
547         if (num_attributes > 0) {
548           uint32_t i;
549           for (i = 0; i < num_attributes; ++i) {
550             attr = attributes.AttributeAtIndex(i);
551             if (attributes.ExtractFormValueAtIndex(i, form_value)) {
552               switch (attr) {
553               case DW_AT_decl_file:
554                 decl.SetFile(
555                    sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(
556                       form_value.Unsigned()));
557                 break;
558 
559               case DW_AT_decl_line:
560                 decl.SetLine(form_value.Unsigned());
561                 break;
562 
563               case DW_AT_decl_column:
564                 decl.SetColumn(form_value.Unsigned());
565                 break;
566 
567               case DW_AT_name:
568                 type_name_cstr = form_value.AsCString();
569                 type_name_const_str.SetCString(type_name_cstr);
570                 break;
571 
572               case DW_AT_byte_size:
573                 byte_size = form_value.Unsigned();
574                 byte_size_valid = true;
575                 break;
576 
577               case DW_AT_accessibility:
578                 accessibility = DW_ACCESS_to_AccessType(form_value.Unsigned());
579                 break;
580 
581               case DW_AT_declaration:
582                 is_forward_declaration = form_value.Boolean();
583                 break;
584 
585               case DW_AT_APPLE_runtime_class:
586                 class_language = (LanguageType)form_value.Signed();
587                 break;
588 
589               case DW_AT_APPLE_objc_complete_type:
590                 is_complete_objc_class = form_value.Signed();
591                 break;
592               case DW_AT_calling_convention:
593                 calling_convention = form_value.Unsigned();
594                 break;
595 
596               case DW_AT_allocated:
597               case DW_AT_associated:
598               case DW_AT_data_location:
599               case DW_AT_description:
600               case DW_AT_start_scope:
601               case DW_AT_visibility:
602               default:
603               case DW_AT_sibling:
604                 break;
605               }
606             }
607           }
608         }
609 
610         // UniqueDWARFASTType is large, so don't create a local variables on
611         // the stack, put it on the heap. This function is often called
612         // recursively and clang isn't good and sharing the stack space for
613         // variables in different blocks.
614         std::unique_ptr<UniqueDWARFASTType> unique_ast_entry_ap(
615             new UniqueDWARFASTType());
616 
617         ConstString unique_typename(type_name_const_str);
618         Declaration unique_decl(decl);
619 
620         if (type_name_const_str) {
621           LanguageType die_language = die.GetLanguage();
622           if (Language::LanguageIsCPlusPlus(die_language)) {
623             // For C++, we rely solely upon the one definition rule that says
624             // only one thing can exist at a given decl context. We ignore the
625             // file and line that things are declared on.
626             std::string qualified_name;
627             if (die.GetQualifiedName(qualified_name))
628               unique_typename = ConstString(qualified_name);
629             unique_decl.Clear();
630           }
631 
632           if (dwarf->GetUniqueDWARFASTTypeMap().Find(
633                   unique_typename, die, unique_decl,
634                   byte_size_valid ? byte_size : -1, *unique_ast_entry_ap)) {
635             type_sp = unique_ast_entry_ap->m_type_sp;
636             if (type_sp) {
637               dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
638               return type_sp;
639             }
640           }
641         }
642 
643         DEBUG_PRINTF("0x%8.8" PRIx64 ": %s (\"%s\")\n", die.GetID(),
644                      DW_TAG_value_to_name(tag), type_name_cstr);
645 
646         int tag_decl_kind = -1;
647         AccessType default_accessibility = eAccessNone;
648         if (tag == DW_TAG_structure_type) {
649           tag_decl_kind = clang::TTK_Struct;
650           default_accessibility = eAccessPublic;
651         } else if (tag == DW_TAG_union_type) {
652           tag_decl_kind = clang::TTK_Union;
653           default_accessibility = eAccessPublic;
654         } else if (tag == DW_TAG_class_type) {
655           tag_decl_kind = clang::TTK_Class;
656           default_accessibility = eAccessPrivate;
657         }
658 
659         if (byte_size_valid && byte_size == 0 && type_name_cstr &&
660             die.HasChildren() == false &&
661             sc.comp_unit->GetLanguage() == eLanguageTypeObjC) {
662           // Work around an issue with clang at the moment where forward
663           // declarations for objective C classes are emitted as:
664           //  DW_TAG_structure_type [2]
665           //  DW_AT_name( "ForwardObjcClass" )
666           //  DW_AT_byte_size( 0x00 )
667           //  DW_AT_decl_file( "..." )
668           //  DW_AT_decl_line( 1 )
669           //
670           // Note that there is no DW_AT_declaration and there are no children,
671           // and the byte size is zero.
672           is_forward_declaration = true;
673         }
674 
675         if (class_language == eLanguageTypeObjC ||
676             class_language == eLanguageTypeObjC_plus_plus) {
677           if (!is_complete_objc_class &&
678               die.Supports_DW_AT_APPLE_objc_complete_type()) {
679             // We have a valid eSymbolTypeObjCClass class symbol whose name
680             // matches the current objective C class that we are trying to find
681             // and this DIE isn't the complete definition (we checked
682             // is_complete_objc_class above and know it is false), so the real
683             // definition is in here somewhere
684             type_sp = dwarf->FindCompleteObjCDefinitionTypeForDIE(
685                 die, type_name_const_str, true);
686 
687             if (!type_sp) {
688               SymbolFileDWARFDebugMap *debug_map_symfile =
689                   dwarf->GetDebugMapSymfile();
690               if (debug_map_symfile) {
691                 // We weren't able to find a full declaration in this DWARF,
692                 // see if we have a declaration anywhere else...
693                 type_sp =
694                     debug_map_symfile->FindCompleteObjCDefinitionTypeForDIE(
695                         die, type_name_const_str, true);
696               }
697             }
698 
699             if (type_sp) {
700               if (log) {
701                 dwarf->GetObjectFile()->GetModule()->LogMessage(
702                     log, "SymbolFileDWARF(%p) - 0x%8.8x: %s type \"%s\" is an "
703                          "incomplete objc type, complete type is 0x%8.8" PRIx64,
704                     static_cast<void *>(this), die.GetOffset(),
705                     DW_TAG_value_to_name(tag), type_name_cstr,
706                     type_sp->GetID());
707               }
708 
709               // We found a real definition for this type elsewhere so lets use
710               // it and cache the fact that we found a complete type for this
711               // die
712               dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
713               return type_sp;
714             }
715           }
716         }
717 
718         if (is_forward_declaration) {
719           // We have a forward declaration to a type and we need to try and
720           // find a full declaration. We look in the current type index just in
721           // case we have a forward declaration followed by an actual
722           // declarations in the DWARF. If this fails, we need to look
723           // elsewhere...
724           if (log) {
725             dwarf->GetObjectFile()->GetModule()->LogMessage(
726                 log, "SymbolFileDWARF(%p) - 0x%8.8x: %s type \"%s\" is a "
727                      "forward declaration, trying to find complete type",
728                 static_cast<void *>(this), die.GetOffset(),
729                 DW_TAG_value_to_name(tag), type_name_cstr);
730           }
731 
732           // See if the type comes from a DWO module and if so, track down that
733           // type.
734           type_sp = ParseTypeFromDWO(die, log);
735           if (type_sp)
736             return type_sp;
737 
738           DWARFDeclContext die_decl_ctx;
739           die.GetDWARFDeclContext(die_decl_ctx);
740 
741           // type_sp = FindDefinitionTypeForDIE (dwarf_cu, die,
742           // type_name_const_str);
743           type_sp = dwarf->FindDefinitionTypeForDWARFDeclContext(die_decl_ctx);
744 
745           if (!type_sp) {
746             SymbolFileDWARFDebugMap *debug_map_symfile =
747                 dwarf->GetDebugMapSymfile();
748             if (debug_map_symfile) {
749               // We weren't able to find a full declaration in this DWARF, see
750               // if we have a declaration anywhere else...
751               type_sp =
752                   debug_map_symfile->FindDefinitionTypeForDWARFDeclContext(
753                       die_decl_ctx);
754             }
755           }
756 
757           if (type_sp) {
758             if (log) {
759               dwarf->GetObjectFile()->GetModule()->LogMessage(
760                   log, "SymbolFileDWARF(%p) - 0x%8.8x: %s type \"%s\" is a "
761                        "forward declaration, complete type is 0x%8.8" PRIx64,
762                   static_cast<void *>(this), die.GetOffset(),
763                   DW_TAG_value_to_name(tag), type_name_cstr, type_sp->GetID());
764             }
765 
766             // We found a real definition for this type elsewhere so lets use
767             // it and cache the fact that we found a complete type for this die
768             dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
769             clang::DeclContext *defn_decl_ctx = GetCachedClangDeclContextForDIE(
770                 dwarf->DebugInfo()->GetDIE(DIERef(type_sp->GetID(), dwarf)));
771             if (defn_decl_ctx)
772               LinkDeclContextToDIE(defn_decl_ctx, die);
773             return type_sp;
774           }
775         }
776         assert(tag_decl_kind != -1);
777         bool clang_type_was_created = false;
778         clang_type.SetCompilerType(
779             &m_ast, dwarf->GetForwardDeclDieToClangType().lookup(die.GetDIE()));
780         if (!clang_type) {
781           clang::DeclContext *decl_ctx =
782               GetClangDeclContextContainingDIE(die, nullptr);
783 
784           // If your decl context is a record that was imported from another
785           // AST context (in the gmodules case), we need to make sure the type
786           // backing the Decl is complete before adding children to it. This is
787           // not an issue in the non-gmodules case because the debug info will
788           // always contain a full definition of parent types in that case.
789           CompleteExternalTagDeclType(GetClangASTImporter(), decl_ctx, die,
790                                       type_name_cstr);
791 
792           if (accessibility == eAccessNone && decl_ctx) {
793             // Check the decl context that contains this class/struct/union. If
794             // it is a class we must give it an accessibility.
795             const clang::Decl::Kind containing_decl_kind =
796                 decl_ctx->getDeclKind();
797             if (DeclKindIsCXXClass(containing_decl_kind))
798               accessibility = default_accessibility;
799           }
800 
801           ClangASTMetadata metadata;
802           metadata.SetUserID(die.GetID());
803           metadata.SetIsDynamicCXXType(dwarf->ClassOrStructIsVirtual(die));
804 
805           if (type_name_cstr && strchr(type_name_cstr, '<')) {
806             ClangASTContext::TemplateParameterInfos template_param_infos;
807             if (ParseTemplateParameterInfos(die, template_param_infos)) {
808               clang::ClassTemplateDecl *class_template_decl =
809                   m_ast.ParseClassTemplateDecl(decl_ctx, accessibility,
810                                                type_name_cstr, tag_decl_kind,
811                                                template_param_infos);
812               if (!class_template_decl) {
813                 if (log) {
814                   dwarf->GetObjectFile()->GetModule()->LogMessage(
815                     log, "SymbolFileDWARF(%p) - 0x%8.8x: %s type \"%s\" "
816                          "clang::ClassTemplateDecl failed to return a decl.",
817                     static_cast<void *>(this), die.GetOffset(),
818                     DW_TAG_value_to_name(tag), type_name_cstr);
819                 }
820                 return TypeSP();
821               }
822 
823               clang::ClassTemplateSpecializationDecl
824                   *class_specialization_decl =
825                       m_ast.CreateClassTemplateSpecializationDecl(
826                           decl_ctx, class_template_decl, tag_decl_kind,
827                           template_param_infos);
828               clang_type = m_ast.CreateClassTemplateSpecializationType(
829                   class_specialization_decl);
830               clang_type_was_created = true;
831 
832               m_ast.SetMetadata(class_template_decl, metadata);
833               m_ast.SetMetadata(class_specialization_decl, metadata);
834             }
835           }
836 
837           if (!clang_type_was_created) {
838             clang_type_was_created = true;
839             clang_type = m_ast.CreateRecordType(decl_ctx, accessibility,
840                                                 type_name_cstr, tag_decl_kind,
841                                                 class_language, &metadata);
842           }
843         }
844 
845         // Store a forward declaration to this class type in case any
846         // parameters in any class methods need it for the clang types for
847         // function prototypes.
848         LinkDeclContextToDIE(m_ast.GetDeclContextForType(clang_type), die);
849         type_sp.reset(new Type(die.GetID(), dwarf, type_name_const_str,
850                                byte_size, NULL, LLDB_INVALID_UID,
851                                Type::eEncodingIsUID, &decl, clang_type,
852                                Type::eResolveStateForward));
853 
854         type_sp->SetIsCompleteObjCClass(is_complete_objc_class);
855 
856         // Add our type to the unique type map so we don't end up creating many
857         // copies of the same type over and over in the ASTContext for our
858         // module
859         unique_ast_entry_ap->m_type_sp = type_sp;
860         unique_ast_entry_ap->m_die = die;
861         unique_ast_entry_ap->m_declaration = unique_decl;
862         unique_ast_entry_ap->m_byte_size = byte_size;
863         dwarf->GetUniqueDWARFASTTypeMap().Insert(unique_typename,
864                                                  *unique_ast_entry_ap);
865 
866         if (is_forward_declaration && die.HasChildren()) {
867           // Check to see if the DIE actually has a definition, some version of
868           // GCC will
869           // emit DIEs with DW_AT_declaration set to true, but yet still have
870           // subprogram, members, or inheritance, so we can't trust it
871           DWARFDIE child_die = die.GetFirstChild();
872           while (child_die) {
873             switch (child_die.Tag()) {
874             case DW_TAG_inheritance:
875             case DW_TAG_subprogram:
876             case DW_TAG_member:
877             case DW_TAG_APPLE_property:
878             case DW_TAG_class_type:
879             case DW_TAG_structure_type:
880             case DW_TAG_enumeration_type:
881             case DW_TAG_typedef:
882             case DW_TAG_union_type:
883               child_die.Clear();
884               is_forward_declaration = false;
885               break;
886             default:
887               child_die = child_die.GetSibling();
888               break;
889             }
890           }
891         }
892 
893         if (!is_forward_declaration) {
894           // Always start the definition for a class type so that if the class
895           // has child classes or types that require the class to be created
896           // for use as their decl contexts the class will be ready to accept
897           // these child definitions.
898           if (die.HasChildren() == false) {
899             // No children for this struct/union/class, lets finish it
900             if (ClangASTContext::StartTagDeclarationDefinition(clang_type)) {
901               ClangASTContext::CompleteTagDeclarationDefinition(clang_type);
902             } else {
903               dwarf->GetObjectFile()->GetModule()->ReportError(
904                   "DWARF DIE at 0x%8.8x named \"%s\" was not able to start its "
905                   "definition.\nPlease file a bug and attach the file at the "
906                   "start of this error message",
907                   die.GetOffset(), type_name_cstr);
908             }
909 
910             if (tag == DW_TAG_structure_type) // this only applies in C
911             {
912               clang::RecordDecl *record_decl =
913                   ClangASTContext::GetAsRecordDecl(clang_type);
914 
915               if (record_decl) {
916                 GetClangASTImporter().InsertRecordDecl(
917                     record_decl, ClangASTImporter::LayoutInfo());
918               }
919             }
920           } else if (clang_type_was_created) {
921             // Start the definition if the class is not objective C since the
922             // underlying decls respond to isCompleteDefinition(). Objective
923             // C decls don't respond to isCompleteDefinition() so we can't
924             // start the declaration definition right away. For C++
925             // class/union/structs we want to start the definition in case the
926             // class is needed as the declaration context for a contained class
927             // or type without the need to complete that type..
928 
929             if (class_language != eLanguageTypeObjC &&
930                 class_language != eLanguageTypeObjC_plus_plus)
931               ClangASTContext::StartTagDeclarationDefinition(clang_type);
932 
933             // Leave this as a forward declaration until we need to know the
934             // details of the type. lldb_private::Type will automatically call
935             // the SymbolFile virtual function
936             // "SymbolFileDWARF::CompleteType(Type *)" When the definition
937             // needs to be defined.
938             assert(!dwarf->GetForwardDeclClangTypeToDie().count(
939                        ClangUtil::RemoveFastQualifiers(clang_type)
940                            .GetOpaqueQualType()) &&
941                    "Type already in the forward declaration map!");
942             // Can't assume m_ast.GetSymbolFile() is actually a
943             // SymbolFileDWARF, it can be a SymbolFileDWARFDebugMap for Apple
944             // binaries.
945             dwarf->GetForwardDeclDieToClangType()[die.GetDIE()] =
946                 clang_type.GetOpaqueQualType();
947             dwarf->GetForwardDeclClangTypeToDie()
948                 [ClangUtil::RemoveFastQualifiers(clang_type)
949                      .GetOpaqueQualType()] = die.GetDIERef();
950             m_ast.SetHasExternalStorage(clang_type.GetOpaqueQualType(), true);
951           }
952         }
953 
954         // If we made a clang type, set the trivial abi if applicable: We only
955         // do this for pass by value - which implies the Trivial ABI. There
956         // isn't a way to assert that something that would normally be pass by
957         // value is pass by reference, so we ignore that attribute if set.
958         if (calling_convention == llvm::dwarf::DW_CC_pass_by_value) {
959           clang::CXXRecordDecl *record_decl =
960                   m_ast.GetAsCXXRecordDecl(clang_type.GetOpaqueQualType());
961           if (record_decl) {
962             record_decl->setHasTrivialSpecialMemberForCall();
963           }
964         }
965 
966       } break;
967 
968       case DW_TAG_enumeration_type: {
969         // Set a bit that lets us know that we are currently parsing this
970         dwarf->GetDIEToType()[die.GetDIE()] = DIE_IS_BEING_PARSED;
971 
972         bool is_scoped = false;
973         DWARFFormValue encoding_form;
974 
975         const size_t num_attributes = die.GetAttributes(attributes);
976         if (num_attributes > 0) {
977           uint32_t i;
978 
979           for (i = 0; i < num_attributes; ++i) {
980             attr = attributes.AttributeAtIndex(i);
981             if (attributes.ExtractFormValueAtIndex(i, form_value)) {
982               switch (attr) {
983               case DW_AT_decl_file:
984                 decl.SetFile(sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(
985                     form_value.Unsigned()));
986                 break;
987               case DW_AT_decl_line:
988                 decl.SetLine(form_value.Unsigned());
989                 break;
990               case DW_AT_decl_column:
991                 decl.SetColumn(form_value.Unsigned());
992                 break;
993               case DW_AT_name:
994                 type_name_cstr = form_value.AsCString();
995                 type_name_const_str.SetCString(type_name_cstr);
996                 break;
997               case DW_AT_type:
998                 encoding_form = form_value;
999                 break;
1000               case DW_AT_byte_size:
1001                 byte_size = form_value.Unsigned();
1002                 break;
1003               case DW_AT_accessibility:
1004                 break; // accessibility =
1005                        // DW_ACCESS_to_AccessType(form_value.Unsigned()); break;
1006               case DW_AT_declaration:
1007                 is_forward_declaration = form_value.Boolean();
1008                 break;
1009               case DW_AT_enum_class:
1010                 is_scoped = form_value.Boolean();
1011                 break;
1012               case DW_AT_allocated:
1013               case DW_AT_associated:
1014               case DW_AT_bit_stride:
1015               case DW_AT_byte_stride:
1016               case DW_AT_data_location:
1017               case DW_AT_description:
1018               case DW_AT_start_scope:
1019               case DW_AT_visibility:
1020               case DW_AT_specification:
1021               case DW_AT_abstract_origin:
1022               case DW_AT_sibling:
1023                 break;
1024               }
1025             }
1026           }
1027 
1028           if (is_forward_declaration) {
1029             type_sp = ParseTypeFromDWO(die, log);
1030             if (type_sp)
1031               return type_sp;
1032 
1033             DWARFDeclContext die_decl_ctx;
1034             die.GetDWARFDeclContext(die_decl_ctx);
1035 
1036             type_sp =
1037                 dwarf->FindDefinitionTypeForDWARFDeclContext(die_decl_ctx);
1038 
1039             if (!type_sp) {
1040               SymbolFileDWARFDebugMap *debug_map_symfile =
1041                   dwarf->GetDebugMapSymfile();
1042               if (debug_map_symfile) {
1043                 // We weren't able to find a full declaration in this DWARF,
1044                 // see if we have a declaration anywhere else...
1045                 type_sp =
1046                     debug_map_symfile->FindDefinitionTypeForDWARFDeclContext(
1047                         die_decl_ctx);
1048               }
1049             }
1050 
1051             if (type_sp) {
1052               if (log) {
1053                 dwarf->GetObjectFile()->GetModule()->LogMessage(
1054                     log, "SymbolFileDWARF(%p) - 0x%8.8x: %s type \"%s\" is a "
1055                          "forward declaration, complete type is 0x%8.8" PRIx64,
1056                     static_cast<void *>(this), die.GetOffset(),
1057                     DW_TAG_value_to_name(tag), type_name_cstr,
1058                     type_sp->GetID());
1059               }
1060 
1061               // We found a real definition for this type elsewhere so lets use
1062               // it and cache the fact that we found a complete type for this
1063               // die
1064               dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
1065               clang::DeclContext *defn_decl_ctx =
1066                   GetCachedClangDeclContextForDIE(dwarf->DebugInfo()->GetDIE(
1067                       DIERef(type_sp->GetID(), dwarf)));
1068               if (defn_decl_ctx)
1069                 LinkDeclContextToDIE(defn_decl_ctx, die);
1070               return type_sp;
1071             }
1072           }
1073           DEBUG_PRINTF("0x%8.8" PRIx64 ": %s (\"%s\")\n", die.GetID(),
1074                        DW_TAG_value_to_name(tag), type_name_cstr);
1075 
1076           CompilerType enumerator_clang_type;
1077           clang_type.SetCompilerType(
1078               &m_ast,
1079               dwarf->GetForwardDeclDieToClangType().lookup(die.GetDIE()));
1080           if (!clang_type) {
1081             if (encoding_form.IsValid()) {
1082               Type *enumerator_type =
1083                   dwarf->ResolveTypeUID(DIERef(encoding_form));
1084               if (enumerator_type)
1085                 enumerator_clang_type = enumerator_type->GetFullCompilerType();
1086             }
1087 
1088             if (!enumerator_clang_type) {
1089               if (byte_size > 0) {
1090                 enumerator_clang_type =
1091                     m_ast.GetBuiltinTypeForDWARFEncodingAndBitSize(
1092                         NULL, DW_ATE_signed, byte_size * 8);
1093               } else {
1094                 enumerator_clang_type = m_ast.GetBasicType(eBasicTypeInt);
1095               }
1096             }
1097 
1098             clang_type = m_ast.CreateEnumerationType(
1099                 type_name_cstr, GetClangDeclContextContainingDIE(die, nullptr),
1100                 decl, enumerator_clang_type, is_scoped);
1101           } else {
1102             enumerator_clang_type =
1103                 m_ast.GetEnumerationIntegerType(clang_type.GetOpaqueQualType());
1104           }
1105 
1106           LinkDeclContextToDIE(
1107               ClangASTContext::GetDeclContextForType(clang_type), die);
1108 
1109           type_sp.reset(new Type(
1110               die.GetID(), dwarf, type_name_const_str, byte_size, NULL,
1111               DIERef(encoding_form).GetUID(dwarf), Type::eEncodingIsUID, &decl,
1112               clang_type, Type::eResolveStateForward));
1113 
1114           if (ClangASTContext::StartTagDeclarationDefinition(clang_type)) {
1115             if (die.HasChildren()) {
1116               SymbolContext cu_sc(die.GetLLDBCompileUnit());
1117               bool is_signed = false;
1118               enumerator_clang_type.IsIntegerType(is_signed);
1119               ParseChildEnumerators(cu_sc, clang_type, is_signed,
1120                                     type_sp->GetByteSize(), die);
1121             }
1122             ClangASTContext::CompleteTagDeclarationDefinition(clang_type);
1123           } else {
1124             dwarf->GetObjectFile()->GetModule()->ReportError(
1125                 "DWARF DIE at 0x%8.8x named \"%s\" was not able to start its "
1126                 "definition.\nPlease file a bug and attach the file at the "
1127                 "start of this error message",
1128                 die.GetOffset(), type_name_cstr);
1129           }
1130         }
1131       } break;
1132 
1133       case DW_TAG_inlined_subroutine:
1134       case DW_TAG_subprogram:
1135       case DW_TAG_subroutine_type: {
1136         // Set a bit that lets us know that we are currently parsing this
1137         dwarf->GetDIEToType()[die.GetDIE()] = DIE_IS_BEING_PARSED;
1138 
1139         DWARFFormValue type_die_form;
1140         bool is_variadic = false;
1141         bool is_inline = false;
1142         bool is_static = false;
1143         bool is_virtual = false;
1144         bool is_explicit = false;
1145         bool is_artificial = false;
1146         bool has_template_params = false;
1147         DWARFFormValue specification_die_form;
1148         DWARFFormValue abstract_origin_die_form;
1149         dw_offset_t object_pointer_die_offset = DW_INVALID_OFFSET;
1150 
1151         unsigned type_quals = 0;
1152         clang::StorageClass storage =
1153             clang::SC_None; //, Extern, Static, PrivateExtern
1154 
1155         const size_t num_attributes = die.GetAttributes(attributes);
1156         if (num_attributes > 0) {
1157           uint32_t i;
1158           for (i = 0; i < num_attributes; ++i) {
1159             attr = attributes.AttributeAtIndex(i);
1160             if (attributes.ExtractFormValueAtIndex(i, form_value)) {
1161               switch (attr) {
1162               case DW_AT_decl_file:
1163                 decl.SetFile(sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(
1164                     form_value.Unsigned()));
1165                 break;
1166               case DW_AT_decl_line:
1167                 decl.SetLine(form_value.Unsigned());
1168                 break;
1169               case DW_AT_decl_column:
1170                 decl.SetColumn(form_value.Unsigned());
1171                 break;
1172               case DW_AT_name:
1173                 type_name_cstr = form_value.AsCString();
1174                 type_name_const_str.SetCString(type_name_cstr);
1175                 break;
1176 
1177               case DW_AT_linkage_name:
1178               case DW_AT_MIPS_linkage_name:
1179                 mangled_name_cstr = form_value.AsCString();
1180                 break;
1181               case DW_AT_type:
1182                 type_die_form = form_value;
1183                 break;
1184               case DW_AT_accessibility:
1185                 accessibility = DW_ACCESS_to_AccessType(form_value.Unsigned());
1186                 break;
1187               case DW_AT_declaration:
1188                 break; // is_forward_declaration = form_value.Boolean(); break;
1189               case DW_AT_inline:
1190                 is_inline = form_value.Boolean();
1191                 break;
1192               case DW_AT_virtuality:
1193                 is_virtual = form_value.Boolean();
1194                 break;
1195               case DW_AT_explicit:
1196                 is_explicit = form_value.Boolean();
1197                 break;
1198               case DW_AT_artificial:
1199                 is_artificial = form_value.Boolean();
1200                 break;
1201 
1202               case DW_AT_external:
1203                 if (form_value.Unsigned()) {
1204                   if (storage == clang::SC_None)
1205                     storage = clang::SC_Extern;
1206                   else
1207                     storage = clang::SC_PrivateExtern;
1208                 }
1209                 break;
1210 
1211               case DW_AT_specification:
1212                 specification_die_form = form_value;
1213                 break;
1214 
1215               case DW_AT_abstract_origin:
1216                 abstract_origin_die_form = form_value;
1217                 break;
1218 
1219               case DW_AT_object_pointer:
1220                 object_pointer_die_offset = form_value.Reference();
1221                 break;
1222 
1223               case DW_AT_allocated:
1224               case DW_AT_associated:
1225               case DW_AT_address_class:
1226               case DW_AT_calling_convention:
1227               case DW_AT_data_location:
1228               case DW_AT_elemental:
1229               case DW_AT_entry_pc:
1230               case DW_AT_frame_base:
1231               case DW_AT_high_pc:
1232               case DW_AT_low_pc:
1233               case DW_AT_prototyped:
1234               case DW_AT_pure:
1235               case DW_AT_ranges:
1236               case DW_AT_recursive:
1237               case DW_AT_return_addr:
1238               case DW_AT_segment:
1239               case DW_AT_start_scope:
1240               case DW_AT_static_link:
1241               case DW_AT_trampoline:
1242               case DW_AT_visibility:
1243               case DW_AT_vtable_elem_location:
1244               case DW_AT_description:
1245               case DW_AT_sibling:
1246                 break;
1247               }
1248             }
1249           }
1250         }
1251 
1252         std::string object_pointer_name;
1253         if (object_pointer_die_offset != DW_INVALID_OFFSET) {
1254           DWARFDIE object_pointer_die = die.GetDIE(object_pointer_die_offset);
1255           if (object_pointer_die) {
1256             const char *object_pointer_name_cstr = object_pointer_die.GetName();
1257             if (object_pointer_name_cstr)
1258               object_pointer_name = object_pointer_name_cstr;
1259           }
1260         }
1261 
1262         DEBUG_PRINTF("0x%8.8" PRIx64 ": %s (\"%s\")\n", die.GetID(),
1263                      DW_TAG_value_to_name(tag), type_name_cstr);
1264 
1265         CompilerType return_clang_type;
1266         Type *func_type = NULL;
1267 
1268         if (type_die_form.IsValid())
1269           func_type = dwarf->ResolveTypeUID(DIERef(type_die_form));
1270 
1271         if (func_type)
1272           return_clang_type = func_type->GetForwardCompilerType();
1273         else
1274           return_clang_type = m_ast.GetBasicType(eBasicTypeVoid);
1275 
1276         std::vector<CompilerType> function_param_types;
1277         std::vector<clang::ParmVarDecl *> function_param_decls;
1278 
1279         // Parse the function children for the parameters
1280 
1281         DWARFDIE decl_ctx_die;
1282         clang::DeclContext *containing_decl_ctx =
1283             GetClangDeclContextContainingDIE(die, &decl_ctx_die);
1284         const clang::Decl::Kind containing_decl_kind =
1285             containing_decl_ctx->getDeclKind();
1286 
1287         bool is_cxx_method = DeclKindIsCXXClass(containing_decl_kind);
1288         // Start off static. This will be set to false in
1289         // ParseChildParameters(...) if we find a "this" parameters as the
1290         // first parameter
1291         if (is_cxx_method) {
1292           is_static = true;
1293         }
1294 
1295         if (die.HasChildren()) {
1296           bool skip_artificial = true;
1297           ParseChildParameters(sc, containing_decl_ctx, die, skip_artificial,
1298                                is_static, is_variadic, has_template_params,
1299                                function_param_types, function_param_decls,
1300                                type_quals);
1301         }
1302 
1303         bool ignore_containing_context = false;
1304         // Check for templatized class member functions. If we had any
1305         // DW_TAG_template_type_parameter or DW_TAG_template_value_parameter
1306         // the DW_TAG_subprogram DIE, then we can't let this become a method in
1307         // a class. Why? Because templatized functions are only emitted if one
1308         // of the templatized methods is used in the current compile unit and
1309         // we will end up with classes that may or may not include these member
1310         // functions and this means one class won't match another class
1311         // definition and it affects our ability to use a class in the clang
1312         // expression parser. So for the greater good, we currently must not
1313         // allow any template member functions in a class definition.
1314         if (is_cxx_method && has_template_params) {
1315           ignore_containing_context = true;
1316           is_cxx_method = false;
1317         }
1318 
1319         // clang_type will get the function prototype clang type after this
1320         // call
1321         clang_type = m_ast.CreateFunctionType(
1322             return_clang_type, function_param_types.data(),
1323             function_param_types.size(), is_variadic, type_quals);
1324 
1325         if (type_name_cstr) {
1326           bool type_handled = false;
1327           if (tag == DW_TAG_subprogram || tag == DW_TAG_inlined_subroutine) {
1328             ObjCLanguage::MethodName objc_method(type_name_cstr, true);
1329             if (objc_method.IsValid(true)) {
1330               CompilerType class_opaque_type;
1331               ConstString class_name(objc_method.GetClassName());
1332               if (class_name) {
1333                 TypeSP complete_objc_class_type_sp(
1334                     dwarf->FindCompleteObjCDefinitionTypeForDIE(
1335                         DWARFDIE(), class_name, false));
1336 
1337                 if (complete_objc_class_type_sp) {
1338                   CompilerType type_clang_forward_type =
1339                       complete_objc_class_type_sp->GetForwardCompilerType();
1340                   if (ClangASTContext::IsObjCObjectOrInterfaceType(
1341                           type_clang_forward_type))
1342                     class_opaque_type = type_clang_forward_type;
1343                 }
1344               }
1345 
1346               if (class_opaque_type) {
1347                 // If accessibility isn't set to anything valid, assume public
1348                 // for now...
1349                 if (accessibility == eAccessNone)
1350                   accessibility = eAccessPublic;
1351 
1352                 clang::ObjCMethodDecl *objc_method_decl =
1353                     m_ast.AddMethodToObjCObjectType(
1354                         class_opaque_type, type_name_cstr, clang_type,
1355                         accessibility, is_artificial, is_variadic);
1356                 type_handled = objc_method_decl != NULL;
1357                 if (type_handled) {
1358                   LinkDeclContextToDIE(
1359                       ClangASTContext::GetAsDeclContext(objc_method_decl), die);
1360                   m_ast.SetMetadataAsUserID(objc_method_decl, die.GetID());
1361                 } else {
1362                   dwarf->GetObjectFile()->GetModule()->ReportError(
1363                       "{0x%8.8x}: invalid Objective-C method 0x%4.4x (%s), "
1364                       "please file a bug and attach the file at the start of "
1365                       "this error message",
1366                       die.GetOffset(), tag, DW_TAG_value_to_name(tag));
1367                 }
1368               }
1369             } else if (is_cxx_method) {
1370               // Look at the parent of this DIE and see if is is a class or
1371               // struct and see if this is actually a C++ method
1372               Type *class_type = dwarf->ResolveType(decl_ctx_die);
1373               if (class_type) {
1374                 bool alternate_defn = false;
1375                 if (class_type->GetID() != decl_ctx_die.GetID() ||
1376                     decl_ctx_die.GetContainingDWOModuleDIE()) {
1377                   alternate_defn = true;
1378 
1379                   // We uniqued the parent class of this function to another
1380                   // class so we now need to associate all dies under
1381                   // "decl_ctx_die" to DIEs in the DIE for "class_type"...
1382                   SymbolFileDWARF *class_symfile = NULL;
1383                   DWARFDIE class_type_die;
1384 
1385                   SymbolFileDWARFDebugMap *debug_map_symfile =
1386                       dwarf->GetDebugMapSymfile();
1387                   if (debug_map_symfile) {
1388                     class_symfile = debug_map_symfile->GetSymbolFileByOSOIndex(
1389                         SymbolFileDWARFDebugMap::GetOSOIndexFromUserID(
1390                             class_type->GetID()));
1391                     class_type_die = class_symfile->DebugInfo()->GetDIE(
1392                         DIERef(class_type->GetID(), dwarf));
1393                   } else {
1394                     class_symfile = dwarf;
1395                     class_type_die = dwarf->DebugInfo()->GetDIE(
1396                         DIERef(class_type->GetID(), dwarf));
1397                   }
1398                   if (class_type_die) {
1399                     DWARFDIECollection failures;
1400 
1401                     CopyUniqueClassMethodTypes(decl_ctx_die, class_type_die,
1402                                                class_type, failures);
1403 
1404                     // FIXME do something with these failures that's smarter
1405                     // than
1406                     // just dropping them on the ground.  Unfortunately classes
1407                     // don't like having stuff added to them after their
1408                     // definitions are complete...
1409 
1410                     type_ptr = dwarf->GetDIEToType()[die.GetDIE()];
1411                     if (type_ptr && type_ptr != DIE_IS_BEING_PARSED) {
1412                       type_sp = type_ptr->shared_from_this();
1413                       break;
1414                     }
1415                   }
1416                 }
1417 
1418                 if (specification_die_form.IsValid()) {
1419                   // We have a specification which we are going to base our
1420                   // function prototype off of, so we need this type to be
1421                   // completed so that the m_die_to_decl_ctx for the method in
1422                   // the specification has a valid clang decl context.
1423                   class_type->GetForwardCompilerType();
1424                   // If we have a specification, then the function type should
1425                   // have been made with the specification and not with this
1426                   // die.
1427                   DWARFDIE spec_die = dwarf->DebugInfo()->GetDIE(
1428                       DIERef(specification_die_form));
1429                   clang::DeclContext *spec_clang_decl_ctx =
1430                       GetClangDeclContextForDIE(spec_die);
1431                   if (spec_clang_decl_ctx) {
1432                     LinkDeclContextToDIE(spec_clang_decl_ctx, die);
1433                   } else {
1434                     dwarf->GetObjectFile()->GetModule()->ReportWarning(
1435                         "0x%8.8" PRIx64 ": DW_AT_specification(0x%8.8" PRIx64
1436                         ") has no decl\n",
1437                         die.GetID(), specification_die_form.Reference());
1438                   }
1439                   type_handled = true;
1440                 } else if (abstract_origin_die_form.IsValid()) {
1441                   // We have a specification which we are going to base our
1442                   // function prototype off of, so we need this type to be
1443                   // completed so that the m_die_to_decl_ctx for the method in
1444                   // the abstract origin has a valid clang decl context.
1445                   class_type->GetForwardCompilerType();
1446 
1447                   DWARFDIE abs_die = dwarf->DebugInfo()->GetDIE(
1448                       DIERef(abstract_origin_die_form));
1449                   clang::DeclContext *abs_clang_decl_ctx =
1450                       GetClangDeclContextForDIE(abs_die);
1451                   if (abs_clang_decl_ctx) {
1452                     LinkDeclContextToDIE(abs_clang_decl_ctx, die);
1453                   } else {
1454                     dwarf->GetObjectFile()->GetModule()->ReportWarning(
1455                         "0x%8.8" PRIx64 ": DW_AT_abstract_origin(0x%8.8" PRIx64
1456                         ") has no decl\n",
1457                         die.GetID(), abstract_origin_die_form.Reference());
1458                   }
1459                   type_handled = true;
1460                 } else {
1461                   CompilerType class_opaque_type =
1462                       class_type->GetForwardCompilerType();
1463                   if (ClangASTContext::IsCXXClassType(class_opaque_type)) {
1464                     if (class_opaque_type.IsBeingDefined() || alternate_defn) {
1465                       if (!is_static && !die.HasChildren()) {
1466                         // We have a C++ member function with no children (this
1467                         // pointer!) and clang will get mad if we try and make
1468                         // a function that isn't well formed in the DWARF, so
1469                         // we will just skip it...
1470                         type_handled = true;
1471                       } else {
1472                         bool add_method = true;
1473                         if (alternate_defn) {
1474                           // If an alternate definition for the class exists,
1475                           // then add the method only if an equivalent is not
1476                           // already present.
1477                           clang::CXXRecordDecl *record_decl =
1478                               m_ast.GetAsCXXRecordDecl(
1479                                   class_opaque_type.GetOpaqueQualType());
1480                           if (record_decl) {
1481                             for (auto method_iter = record_decl->method_begin();
1482                                  method_iter != record_decl->method_end();
1483                                  method_iter++) {
1484                               clang::CXXMethodDecl *method_decl = *method_iter;
1485                               if (method_decl->getNameInfo().getAsString() ==
1486                                   std::string(type_name_cstr)) {
1487                                 if (method_decl->getType() ==
1488                                     ClangUtil::GetQualType(clang_type)) {
1489                                   add_method = false;
1490                                   LinkDeclContextToDIE(
1491                                       ClangASTContext::GetAsDeclContext(
1492                                           method_decl),
1493                                       die);
1494                                   type_handled = true;
1495 
1496                                   break;
1497                                 }
1498                               }
1499                             }
1500                           }
1501                         }
1502 
1503                         if (add_method) {
1504                           llvm::PrettyStackTraceFormat stack_trace(
1505                               "SymbolFileDWARF::ParseType() is adding a method "
1506                               "%s to class %s in DIE 0x%8.8" PRIx64 " from %s",
1507                               type_name_cstr,
1508                               class_type->GetName().GetCString(), die.GetID(),
1509                               dwarf->GetObjectFile()
1510                                   ->GetFileSpec()
1511                                   .GetPath()
1512                                   .c_str());
1513 
1514                           const bool is_attr_used = false;
1515                           // Neither GCC 4.2 nor clang++ currently set a valid
1516                           // accessibility in the DWARF for C++ methods...
1517                           // Default to public for now...
1518                           if (accessibility == eAccessNone)
1519                             accessibility = eAccessPublic;
1520 
1521                           clang::CXXMethodDecl *cxx_method_decl =
1522                               m_ast.AddMethodToCXXRecordType(
1523                                   class_opaque_type.GetOpaqueQualType(),
1524                                   type_name_cstr, mangled_name_cstr, clang_type,
1525                                   accessibility, is_virtual, is_static,
1526                                   is_inline, is_explicit, is_attr_used,
1527                                   is_artificial);
1528 
1529                           type_handled = cxx_method_decl != NULL;
1530 
1531                           if (type_handled) {
1532                             LinkDeclContextToDIE(
1533                                 ClangASTContext::GetAsDeclContext(
1534                                     cxx_method_decl),
1535                                 die);
1536 
1537                             ClangASTMetadata metadata;
1538                             metadata.SetUserID(die.GetID());
1539 
1540                             if (!object_pointer_name.empty()) {
1541                               metadata.SetObjectPtrName(
1542                                   object_pointer_name.c_str());
1543                               if (log)
1544                                 log->Printf(
1545                                     "Setting object pointer name: %s on method "
1546                                     "object %p.\n",
1547                                     object_pointer_name.c_str(),
1548                                     static_cast<void *>(cxx_method_decl));
1549                             }
1550                             m_ast.SetMetadata(cxx_method_decl, metadata);
1551                           } else {
1552                             ignore_containing_context = true;
1553                           }
1554                         }
1555                       }
1556                     } else {
1557                       // We were asked to parse the type for a method in a
1558                       // class, yet the class hasn't been asked to complete
1559                       // itself through the clang::ExternalASTSource protocol,
1560                       // so we need to just have the class complete itself and
1561                       // do things the right way, then our
1562                       // DIE should then have an entry in the
1563                       // dwarf->GetDIEToType() map. First
1564                       // we need to modify the dwarf->GetDIEToType() so it
1565                       // doesn't think we are trying to parse this DIE
1566                       // anymore...
1567                       dwarf->GetDIEToType()[die.GetDIE()] = NULL;
1568 
1569                       // Now we get the full type to force our class type to
1570                       // complete itself using the clang::ExternalASTSource
1571                       // protocol which will parse all base classes and all
1572                       // methods (including the method for this DIE).
1573                       class_type->GetFullCompilerType();
1574 
1575                       // The type for this DIE should have been filled in the
1576                       // function call above
1577                       type_ptr = dwarf->GetDIEToType()[die.GetDIE()];
1578                       if (type_ptr && type_ptr != DIE_IS_BEING_PARSED) {
1579                         type_sp = type_ptr->shared_from_this();
1580                         break;
1581                       }
1582 
1583                       // FIXME This is fixing some even uglier behavior but we
1584                       // really need to
1585                       // uniq the methods of each class as well as the class
1586                       // itself. <rdar://problem/11240464>
1587                       type_handled = true;
1588                     }
1589                   }
1590                 }
1591               }
1592             }
1593           }
1594 
1595           if (!type_handled) {
1596             clang::FunctionDecl *function_decl = nullptr;
1597 
1598             if (abstract_origin_die_form.IsValid()) {
1599               DWARFDIE abs_die =
1600                   dwarf->DebugInfo()->GetDIE(DIERef(abstract_origin_die_form));
1601 
1602               SymbolContext sc;
1603 
1604               if (dwarf->ResolveType(abs_die)) {
1605                 function_decl = llvm::dyn_cast_or_null<clang::FunctionDecl>(
1606                     GetCachedClangDeclContextForDIE(abs_die));
1607 
1608                 if (function_decl) {
1609                   LinkDeclContextToDIE(function_decl, die);
1610                 }
1611               }
1612             }
1613 
1614             if (!function_decl) {
1615               // We just have a function that isn't part of a class
1616               function_decl = m_ast.CreateFunctionDeclaration(
1617                   ignore_containing_context ? m_ast.GetTranslationUnitDecl()
1618                                             : containing_decl_ctx,
1619                   type_name_cstr, clang_type, storage, is_inline);
1620 
1621               if (has_template_params) {
1622                 ClangASTContext::TemplateParameterInfos template_param_infos;
1623                 ParseTemplateParameterInfos(die, template_param_infos);
1624                 clang::FunctionTemplateDecl *func_template_decl =
1625                     m_ast.CreateFunctionTemplateDecl(
1626                         containing_decl_ctx, function_decl, type_name_cstr,
1627                         template_param_infos);
1628                 m_ast.CreateFunctionTemplateSpecializationInfo(
1629                     function_decl, func_template_decl, template_param_infos);
1630               }
1631 
1632               lldbassert(function_decl);
1633 
1634               if (function_decl) {
1635                 LinkDeclContextToDIE(function_decl, die);
1636 
1637                 if (!function_param_decls.empty())
1638                   m_ast.SetFunctionParameters(function_decl,
1639                                               &function_param_decls.front(),
1640                                               function_param_decls.size());
1641 
1642                 ClangASTMetadata metadata;
1643                 metadata.SetUserID(die.GetID());
1644 
1645                 if (!object_pointer_name.empty()) {
1646                   metadata.SetObjectPtrName(object_pointer_name.c_str());
1647                   if (log)
1648                     log->Printf("Setting object pointer name: %s on function "
1649                                 "object %p.",
1650                                 object_pointer_name.c_str(),
1651                                 static_cast<void *>(function_decl));
1652                 }
1653                 m_ast.SetMetadata(function_decl, metadata);
1654               }
1655             }
1656           }
1657         }
1658         type_sp.reset(new Type(die.GetID(), dwarf, type_name_const_str, 0, NULL,
1659                                LLDB_INVALID_UID, Type::eEncodingIsUID, &decl,
1660                                clang_type, Type::eResolveStateFull));
1661         assert(type_sp.get());
1662       } break;
1663 
1664       case DW_TAG_array_type: {
1665         // Set a bit that lets us know that we are currently parsing this
1666         dwarf->GetDIEToType()[die.GetDIE()] = DIE_IS_BEING_PARSED;
1667 
1668         DWARFFormValue type_die_form;
1669         int64_t first_index = 0;
1670         uint32_t byte_stride = 0;
1671         uint32_t bit_stride = 0;
1672         bool is_vector = false;
1673         const size_t num_attributes = die.GetAttributes(attributes);
1674 
1675         if (num_attributes > 0) {
1676           uint32_t i;
1677           for (i = 0; i < num_attributes; ++i) {
1678             attr = attributes.AttributeAtIndex(i);
1679             if (attributes.ExtractFormValueAtIndex(i, form_value)) {
1680               switch (attr) {
1681               case DW_AT_decl_file:
1682                 decl.SetFile(sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(
1683                     form_value.Unsigned()));
1684                 break;
1685               case DW_AT_decl_line:
1686                 decl.SetLine(form_value.Unsigned());
1687                 break;
1688               case DW_AT_decl_column:
1689                 decl.SetColumn(form_value.Unsigned());
1690                 break;
1691               case DW_AT_name:
1692                 type_name_cstr = form_value.AsCString();
1693                 type_name_const_str.SetCString(type_name_cstr);
1694                 break;
1695 
1696               case DW_AT_type:
1697                 type_die_form = form_value;
1698                 break;
1699               case DW_AT_byte_size:
1700                 break; // byte_size = form_value.Unsigned(); break;
1701               case DW_AT_byte_stride:
1702                 byte_stride = form_value.Unsigned();
1703                 break;
1704               case DW_AT_bit_stride:
1705                 bit_stride = form_value.Unsigned();
1706                 break;
1707               case DW_AT_GNU_vector:
1708                 is_vector = form_value.Boolean();
1709                 break;
1710               case DW_AT_accessibility:
1711                 break; // accessibility =
1712                        // DW_ACCESS_to_AccessType(form_value.Unsigned()); break;
1713               case DW_AT_declaration:
1714                 break; // is_forward_declaration = form_value.Boolean(); break;
1715               case DW_AT_allocated:
1716               case DW_AT_associated:
1717               case DW_AT_data_location:
1718               case DW_AT_description:
1719               case DW_AT_ordering:
1720               case DW_AT_start_scope:
1721               case DW_AT_visibility:
1722               case DW_AT_specification:
1723               case DW_AT_abstract_origin:
1724               case DW_AT_sibling:
1725                 break;
1726               }
1727             }
1728           }
1729 
1730           DEBUG_PRINTF("0x%8.8" PRIx64 ": %s (\"%s\")\n", die.GetID(),
1731                        DW_TAG_value_to_name(tag), type_name_cstr);
1732 
1733           DIERef type_die_ref(type_die_form);
1734           Type *element_type = dwarf->ResolveTypeUID(type_die_ref);
1735 
1736           if (element_type) {
1737             std::vector<uint64_t> element_orders;
1738             ParseChildArrayInfo(sc, die, first_index, element_orders,
1739                                 byte_stride, bit_stride);
1740             if (byte_stride == 0 && bit_stride == 0)
1741               byte_stride = element_type->GetByteSize();
1742             CompilerType array_element_type =
1743                 element_type->GetForwardCompilerType();
1744 
1745             if (ClangASTContext::IsCXXClassType(array_element_type) &&
1746                 array_element_type.GetCompleteType() == false) {
1747               ModuleSP module_sp = die.GetModule();
1748               if (module_sp) {
1749                 if (die.GetCU()->GetProducer() == eProducerClang)
1750                   module_sp->ReportError(
1751                       "DWARF DW_TAG_array_type DIE at 0x%8.8x has a "
1752                       "class/union/struct element type DIE 0x%8.8x that is a "
1753                       "forward declaration, not a complete definition.\nTry "
1754                       "compiling the source file with -fstandalone-debug or "
1755                       "disable -gmodules",
1756                       die.GetOffset(), type_die_ref.die_offset);
1757                 else
1758                   module_sp->ReportError(
1759                       "DWARF DW_TAG_array_type DIE at 0x%8.8x has a "
1760                       "class/union/struct element type DIE 0x%8.8x that is a "
1761                       "forward declaration, not a complete definition.\nPlease "
1762                       "file a bug against the compiler and include the "
1763                       "preprocessed output for %s",
1764                       die.GetOffset(), type_die_ref.die_offset,
1765                       die.GetLLDBCompileUnit()
1766                           ? die.GetLLDBCompileUnit()->GetPath().c_str()
1767                           : "the source file");
1768               }
1769 
1770               // We have no choice other than to pretend that the element class
1771               // type is complete. If we don't do this, clang will crash when
1772               // trying to layout the class. Since we provide layout
1773               // assistance, all ivars in this class and other classes will be
1774               // fine, this is the best we can do short of crashing.
1775               if (ClangASTContext::StartTagDeclarationDefinition(
1776                       array_element_type)) {
1777                 ClangASTContext::CompleteTagDeclarationDefinition(
1778                     array_element_type);
1779               } else {
1780                 module_sp->ReportError("DWARF DIE at 0x%8.8x was not able to "
1781                                        "start its definition.\nPlease file a "
1782                                        "bug and attach the file at the start "
1783                                        "of this error message",
1784                                        type_die_ref.die_offset);
1785               }
1786             }
1787 
1788             uint64_t array_element_bit_stride = byte_stride * 8 + bit_stride;
1789             if (element_orders.size() > 0) {
1790               uint64_t num_elements = 0;
1791               std::vector<uint64_t>::const_reverse_iterator pos;
1792               std::vector<uint64_t>::const_reverse_iterator end =
1793                   element_orders.rend();
1794               for (pos = element_orders.rbegin(); pos != end; ++pos) {
1795                 num_elements = *pos;
1796                 clang_type = m_ast.CreateArrayType(array_element_type,
1797                                                    num_elements, is_vector);
1798                 array_element_type = clang_type;
1799                 array_element_bit_stride =
1800                     num_elements ? array_element_bit_stride * num_elements
1801                                  : array_element_bit_stride;
1802               }
1803             } else {
1804               clang_type =
1805                   m_ast.CreateArrayType(array_element_type, 0, is_vector);
1806             }
1807             ConstString empty_name;
1808             type_sp.reset(new Type(
1809                 die.GetID(), dwarf, empty_name, array_element_bit_stride / 8,
1810                 NULL, DIERef(type_die_form).GetUID(dwarf), Type::eEncodingIsUID,
1811                 &decl, clang_type, Type::eResolveStateFull));
1812             type_sp->SetEncodingType(element_type);
1813           }
1814         }
1815       } break;
1816 
1817       case DW_TAG_ptr_to_member_type: {
1818         DWARFFormValue type_die_form;
1819         DWARFFormValue containing_type_die_form;
1820 
1821         const size_t num_attributes = die.GetAttributes(attributes);
1822 
1823         if (num_attributes > 0) {
1824           uint32_t i;
1825           for (i = 0; i < num_attributes; ++i) {
1826             attr = attributes.AttributeAtIndex(i);
1827             if (attributes.ExtractFormValueAtIndex(i, form_value)) {
1828               switch (attr) {
1829               case DW_AT_type:
1830                 type_die_form = form_value;
1831                 break;
1832               case DW_AT_containing_type:
1833                 containing_type_die_form = form_value;
1834                 break;
1835               }
1836             }
1837           }
1838 
1839           Type *pointee_type = dwarf->ResolveTypeUID(DIERef(type_die_form));
1840           Type *class_type =
1841               dwarf->ResolveTypeUID(DIERef(containing_type_die_form));
1842 
1843           CompilerType pointee_clang_type =
1844               pointee_type->GetForwardCompilerType();
1845           CompilerType class_clang_type = class_type->GetLayoutCompilerType();
1846 
1847           clang_type = ClangASTContext::CreateMemberPointerType(
1848               class_clang_type, pointee_clang_type);
1849 
1850           byte_size = clang_type.GetByteSize(nullptr);
1851 
1852           type_sp.reset(new Type(die.GetID(), dwarf, type_name_const_str,
1853                                  byte_size, NULL, LLDB_INVALID_UID,
1854                                  Type::eEncodingIsUID, NULL, clang_type,
1855                                  Type::eResolveStateForward));
1856         }
1857 
1858         break;
1859       }
1860       default:
1861         dwarf->GetObjectFile()->GetModule()->ReportError(
1862             "{0x%8.8x}: unhandled type tag 0x%4.4x (%s), please file a bug and "
1863             "attach the file at the start of this error message",
1864             die.GetOffset(), tag, DW_TAG_value_to_name(tag));
1865         break;
1866       }
1867 
1868       if (type_sp.get()) {
1869         DWARFDIE sc_parent_die =
1870             SymbolFileDWARF::GetParentSymbolContextDIE(die);
1871         dw_tag_t sc_parent_tag = sc_parent_die.Tag();
1872 
1873         SymbolContextScope *symbol_context_scope = NULL;
1874         if (sc_parent_tag == DW_TAG_compile_unit ||
1875             sc_parent_tag == DW_TAG_partial_unit) {
1876           symbol_context_scope = sc.comp_unit;
1877         } else if (sc.function != NULL && sc_parent_die) {
1878           symbol_context_scope =
1879               sc.function->GetBlock(true).FindBlockByID(sc_parent_die.GetID());
1880           if (symbol_context_scope == NULL)
1881             symbol_context_scope = sc.function;
1882         }
1883 
1884         if (symbol_context_scope != NULL) {
1885           type_sp->SetSymbolContextScope(symbol_context_scope);
1886         }
1887 
1888         // We are ready to put this type into the uniqued list up at the module
1889         // level
1890         type_list->Insert(type_sp);
1891 
1892         dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
1893       }
1894     } else if (type_ptr != DIE_IS_BEING_PARSED) {
1895       type_sp = type_ptr->shared_from_this();
1896     }
1897   }
1898   return type_sp;
1899 }
1900 
1901 // DWARF parsing functions
1902 
1903 class DWARFASTParserClang::DelayedAddObjCClassProperty {
1904 public:
1905   DelayedAddObjCClassProperty(
1906       const CompilerType &class_opaque_type, const char *property_name,
1907       const CompilerType &property_opaque_type, // The property type is only
1908                                                 // required if you don't have an
1909                                                 // ivar decl
1910       clang::ObjCIvarDecl *ivar_decl, const char *property_setter_name,
1911       const char *property_getter_name, uint32_t property_attributes,
1912       const ClangASTMetadata *metadata)
1913       : m_class_opaque_type(class_opaque_type), m_property_name(property_name),
1914         m_property_opaque_type(property_opaque_type), m_ivar_decl(ivar_decl),
1915         m_property_setter_name(property_setter_name),
1916         m_property_getter_name(property_getter_name),
1917         m_property_attributes(property_attributes) {
1918     if (metadata != NULL) {
1919       m_metadata_ap.reset(new ClangASTMetadata());
1920       *m_metadata_ap = *metadata;
1921     }
1922   }
1923 
1924   DelayedAddObjCClassProperty(const DelayedAddObjCClassProperty &rhs) {
1925     *this = rhs;
1926   }
1927 
1928   DelayedAddObjCClassProperty &
1929   operator=(const DelayedAddObjCClassProperty &rhs) {
1930     m_class_opaque_type = rhs.m_class_opaque_type;
1931     m_property_name = rhs.m_property_name;
1932     m_property_opaque_type = rhs.m_property_opaque_type;
1933     m_ivar_decl = rhs.m_ivar_decl;
1934     m_property_setter_name = rhs.m_property_setter_name;
1935     m_property_getter_name = rhs.m_property_getter_name;
1936     m_property_attributes = rhs.m_property_attributes;
1937 
1938     if (rhs.m_metadata_ap.get()) {
1939       m_metadata_ap.reset(new ClangASTMetadata());
1940       *m_metadata_ap = *rhs.m_metadata_ap;
1941     }
1942     return *this;
1943   }
1944 
1945   bool Finalize() {
1946     return ClangASTContext::AddObjCClassProperty(
1947         m_class_opaque_type, m_property_name, m_property_opaque_type,
1948         m_ivar_decl, m_property_setter_name, m_property_getter_name,
1949         m_property_attributes, m_metadata_ap.get());
1950   }
1951 
1952 private:
1953   CompilerType m_class_opaque_type;
1954   const char *m_property_name;
1955   CompilerType m_property_opaque_type;
1956   clang::ObjCIvarDecl *m_ivar_decl;
1957   const char *m_property_setter_name;
1958   const char *m_property_getter_name;
1959   uint32_t m_property_attributes;
1960   std::unique_ptr<ClangASTMetadata> m_metadata_ap;
1961 };
1962 
1963 bool DWARFASTParserClang::ParseTemplateDIE(
1964     const DWARFDIE &die,
1965     ClangASTContext::TemplateParameterInfos &template_param_infos) {
1966   const dw_tag_t tag = die.Tag();
1967   bool is_template_template_argument = false;
1968 
1969   switch (tag) {
1970   case DW_TAG_GNU_template_parameter_pack: {
1971     template_param_infos.packed_args.reset(
1972       new ClangASTContext::TemplateParameterInfos);
1973     for (DWARFDIE child_die = die.GetFirstChild(); child_die.IsValid();
1974          child_die = child_die.GetSibling()) {
1975       if (!ParseTemplateDIE(child_die, *template_param_infos.packed_args))
1976         return false;
1977     }
1978     if (const char *name = die.GetName()) {
1979       template_param_infos.pack_name = name;
1980     }
1981     return true;
1982   }
1983   case DW_TAG_GNU_template_template_param:
1984     is_template_template_argument = true;
1985     LLVM_FALLTHROUGH;
1986   case DW_TAG_template_type_parameter:
1987   case DW_TAG_template_value_parameter: {
1988     DWARFAttributes attributes;
1989     const size_t num_attributes = die.GetAttributes(attributes);
1990     const char *name = nullptr;
1991     const char *template_name = nullptr;
1992     CompilerType clang_type;
1993     uint64_t uval64 = 0;
1994     bool uval64_valid = false;
1995     if (num_attributes > 0) {
1996       DWARFFormValue form_value;
1997       for (size_t i = 0; i < num_attributes; ++i) {
1998         const dw_attr_t attr = attributes.AttributeAtIndex(i);
1999 
2000         switch (attr) {
2001         case DW_AT_name:
2002           if (attributes.ExtractFormValueAtIndex(i, form_value))
2003             name = form_value.AsCString();
2004           break;
2005 
2006         case DW_AT_GNU_template_name:
2007           if (attributes.ExtractFormValueAtIndex(i, form_value))
2008             template_name = form_value.AsCString();
2009           break;
2010 
2011         case DW_AT_type:
2012           if (attributes.ExtractFormValueAtIndex(i, form_value)) {
2013             Type *lldb_type = die.ResolveTypeUID(DIERef(form_value));
2014             if (lldb_type)
2015               clang_type = lldb_type->GetForwardCompilerType();
2016           }
2017           break;
2018 
2019         case DW_AT_const_value:
2020           if (attributes.ExtractFormValueAtIndex(i, form_value)) {
2021             uval64_valid = true;
2022             uval64 = form_value.Unsigned();
2023           }
2024           break;
2025         default:
2026           break;
2027         }
2028       }
2029 
2030       clang::ASTContext *ast = m_ast.getASTContext();
2031       if (!clang_type)
2032         clang_type = m_ast.GetBasicType(eBasicTypeVoid);
2033 
2034       if (!is_template_template_argument) {
2035         bool is_signed = false;
2036         if (name && name[0])
2037           template_param_infos.names.push_back(name);
2038         else
2039           template_param_infos.names.push_back(NULL);
2040 
2041         // Get the signed value for any integer or enumeration if available
2042         clang_type.IsIntegerOrEnumerationType(is_signed);
2043 
2044         if (tag == DW_TAG_template_value_parameter && uval64_valid) {
2045           llvm::APInt apint(clang_type.GetBitSize(nullptr), uval64, is_signed);
2046           template_param_infos.args.push_back(
2047               clang::TemplateArgument(*ast, llvm::APSInt(apint, !is_signed),
2048                                       ClangUtil::GetQualType(clang_type)));
2049         } else {
2050           template_param_infos.args.push_back(
2051               clang::TemplateArgument(ClangUtil::GetQualType(clang_type)));
2052         }
2053       } else {
2054         auto *tplt_type = m_ast.CreateTemplateTemplateParmDecl(template_name);
2055         template_param_infos.names.push_back(name);
2056         template_param_infos.args.push_back(
2057             clang::TemplateArgument(clang::TemplateName(tplt_type)));
2058       }
2059     }
2060   }
2061     return true;
2062 
2063   default:
2064     break;
2065   }
2066   return false;
2067 }
2068 
2069 bool DWARFASTParserClang::ParseTemplateParameterInfos(
2070     const DWARFDIE &parent_die,
2071     ClangASTContext::TemplateParameterInfos &template_param_infos) {
2072 
2073   if (!parent_die)
2074     return false;
2075 
2076   for (DWARFDIE die = parent_die.GetFirstChild(); die.IsValid();
2077        die = die.GetSibling()) {
2078     const dw_tag_t tag = die.Tag();
2079 
2080     switch (tag) {
2081     case DW_TAG_template_type_parameter:
2082     case DW_TAG_template_value_parameter:
2083     case DW_TAG_GNU_template_parameter_pack:
2084     case DW_TAG_GNU_template_template_param:
2085       ParseTemplateDIE(die, template_param_infos);
2086       break;
2087 
2088     default:
2089       break;
2090     }
2091   }
2092   if (template_param_infos.args.empty())
2093     return false;
2094   return template_param_infos.args.size() == template_param_infos.names.size();
2095 }
2096 
2097 bool DWARFASTParserClang::CompleteTypeFromDWARF(const DWARFDIE &die,
2098                                                 lldb_private::Type *type,
2099                                                 CompilerType &clang_type) {
2100   SymbolFileDWARF *dwarf = die.GetDWARF();
2101 
2102   std::lock_guard<std::recursive_mutex> guard(
2103       dwarf->GetObjectFile()->GetModule()->GetMutex());
2104 
2105   // Disable external storage for this type so we don't get anymore
2106   // clang::ExternalASTSource queries for this type.
2107   m_ast.SetHasExternalStorage(clang_type.GetOpaqueQualType(), false);
2108 
2109   if (!die)
2110     return false;
2111 
2112 #if defined LLDB_CONFIGURATION_DEBUG
2113   //----------------------------------------------------------------------
2114   // For debugging purposes, the LLDB_DWARF_DONT_COMPLETE_TYPENAMES environment
2115   // variable can be set with one or more typenames separated by ';'
2116   // characters. This will cause this function to not complete any types whose
2117   // names match.
2118   //
2119   // Examples of setting this environment variable:
2120   //
2121   // LLDB_DWARF_DONT_COMPLETE_TYPENAMES=Foo
2122   // LLDB_DWARF_DONT_COMPLETE_TYPENAMES=Foo;Bar;Baz
2123   //----------------------------------------------------------------------
2124   const char *dont_complete_typenames_cstr =
2125       getenv("LLDB_DWARF_DONT_COMPLETE_TYPENAMES");
2126   if (dont_complete_typenames_cstr && dont_complete_typenames_cstr[0]) {
2127     const char *die_name = die.GetName();
2128     if (die_name && die_name[0]) {
2129       const char *match = strstr(dont_complete_typenames_cstr, die_name);
2130       if (match) {
2131         size_t die_name_length = strlen(die_name);
2132         while (match) {
2133           const char separator_char = ';';
2134           const char next_char = match[die_name_length];
2135           if (next_char == '\0' || next_char == separator_char) {
2136             if (match == dont_complete_typenames_cstr ||
2137                 match[-1] == separator_char)
2138               return false;
2139           }
2140           match = strstr(match + 1, die_name);
2141         }
2142       }
2143     }
2144   }
2145 #endif
2146 
2147   const dw_tag_t tag = die.Tag();
2148 
2149   Log *log =
2150       nullptr; // (LogChannelDWARF::GetLogIfAny(DWARF_LOG_DEBUG_INFO|DWARF_LOG_TYPE_COMPLETION));
2151   if (log)
2152     dwarf->GetObjectFile()->GetModule()->LogMessageVerboseBacktrace(
2153         log, "0x%8.8" PRIx64 ": %s '%s' resolving forward declaration...",
2154         die.GetID(), die.GetTagAsCString(), type->GetName().AsCString());
2155   assert(clang_type);
2156   DWARFAttributes attributes;
2157   switch (tag) {
2158   case DW_TAG_structure_type:
2159   case DW_TAG_union_type:
2160   case DW_TAG_class_type: {
2161     ClangASTImporter::LayoutInfo layout_info;
2162 
2163     {
2164       if (die.HasChildren()) {
2165         LanguageType class_language = eLanguageTypeUnknown;
2166         if (ClangASTContext::IsObjCObjectOrInterfaceType(clang_type)) {
2167           class_language = eLanguageTypeObjC;
2168           // For objective C we don't start the definition when the class is
2169           // created.
2170           ClangASTContext::StartTagDeclarationDefinition(clang_type);
2171         }
2172 
2173         int tag_decl_kind = -1;
2174         AccessType default_accessibility = eAccessNone;
2175         if (tag == DW_TAG_structure_type) {
2176           tag_decl_kind = clang::TTK_Struct;
2177           default_accessibility = eAccessPublic;
2178         } else if (tag == DW_TAG_union_type) {
2179           tag_decl_kind = clang::TTK_Union;
2180           default_accessibility = eAccessPublic;
2181         } else if (tag == DW_TAG_class_type) {
2182           tag_decl_kind = clang::TTK_Class;
2183           default_accessibility = eAccessPrivate;
2184         }
2185 
2186         SymbolContext sc(die.GetLLDBCompileUnit());
2187         std::vector<clang::CXXBaseSpecifier *> base_classes;
2188         std::vector<int> member_accessibilities;
2189         bool is_a_class = false;
2190         // Parse members and base classes first
2191         DWARFDIECollection member_function_dies;
2192 
2193         DelayedPropertyList delayed_properties;
2194         ParseChildMembers(sc, die, clang_type, class_language, base_classes,
2195                           member_accessibilities, member_function_dies,
2196                           delayed_properties, default_accessibility, is_a_class,
2197                           layout_info);
2198 
2199         // Now parse any methods if there were any...
2200         size_t num_functions = member_function_dies.Size();
2201         if (num_functions > 0) {
2202           for (size_t i = 0; i < num_functions; ++i) {
2203             dwarf->ResolveType(member_function_dies.GetDIEAtIndex(i));
2204           }
2205         }
2206 
2207         if (class_language == eLanguageTypeObjC) {
2208           ConstString class_name(clang_type.GetTypeName());
2209           if (class_name) {
2210             DIEArray method_die_offsets;
2211             dwarf->GetObjCMethodDIEOffsets(class_name, method_die_offsets);
2212 
2213             if (!method_die_offsets.empty()) {
2214               DWARFDebugInfo *debug_info = dwarf->DebugInfo();
2215 
2216               const size_t num_matches = method_die_offsets.size();
2217               for (size_t i = 0; i < num_matches; ++i) {
2218                 const DIERef &die_ref = method_die_offsets[i];
2219                 DWARFDIE method_die = debug_info->GetDIE(die_ref);
2220 
2221                 if (method_die)
2222                   method_die.ResolveType();
2223               }
2224             }
2225 
2226             for (DelayedPropertyList::iterator pi = delayed_properties.begin(),
2227                                                pe = delayed_properties.end();
2228                  pi != pe; ++pi)
2229               pi->Finalize();
2230           }
2231         }
2232 
2233         // If we have a DW_TAG_structure_type instead of a DW_TAG_class_type we
2234         // need to tell the clang type it is actually a class.
2235         if (class_language != eLanguageTypeObjC) {
2236           if (is_a_class && tag_decl_kind != clang::TTK_Class)
2237             m_ast.SetTagTypeKind(ClangUtil::GetQualType(clang_type),
2238                                  clang::TTK_Class);
2239         }
2240 
2241         // Since DW_TAG_structure_type gets used for both classes and
2242         // structures, we may need to set any DW_TAG_member fields to have a
2243         // "private" access if none was specified. When we parsed the child
2244         // members we tracked that actual accessibility value for each
2245         // DW_TAG_member in the "member_accessibilities" array. If the value
2246         // for the member is zero, then it was set to the
2247         // "default_accessibility" which for structs was "public". Below we
2248         // correct this by setting any fields to "private" that weren't
2249         // correctly set.
2250         if (is_a_class && !member_accessibilities.empty()) {
2251           // This is a class and all members that didn't have their access
2252           // specified are private.
2253           m_ast.SetDefaultAccessForRecordFields(
2254               m_ast.GetAsRecordDecl(clang_type), eAccessPrivate,
2255               &member_accessibilities.front(), member_accessibilities.size());
2256         }
2257 
2258         if (!base_classes.empty()) {
2259           // Make sure all base classes refer to complete types and not forward
2260           // declarations. If we don't do this, clang will crash with an
2261           // assertion in the call to clang_type.SetBaseClassesForClassType()
2262           for (auto &base_class : base_classes) {
2263             clang::TypeSourceInfo *type_source_info =
2264                 base_class->getTypeSourceInfo();
2265             if (type_source_info) {
2266               CompilerType base_class_type(
2267                   &m_ast, type_source_info->getType().getAsOpaquePtr());
2268               if (base_class_type.GetCompleteType() == false) {
2269                 auto module = dwarf->GetObjectFile()->GetModule();
2270                 module->ReportError(":: Class '%s' has a base class '%s' which "
2271                                     "does not have a complete definition.",
2272                                     die.GetName(),
2273                                     base_class_type.GetTypeName().GetCString());
2274                 if (die.GetCU()->GetProducer() == eProducerClang)
2275                   module->ReportError(":: Try compiling the source file with "
2276                                       "-fstandalone-debug.");
2277 
2278                 // We have no choice other than to pretend that the base class
2279                 // is complete. If we don't do this, clang will crash when we
2280                 // call setBases() inside of
2281                 // "clang_type.SetBaseClassesForClassType()" below. Since we
2282                 // provide layout assistance, all ivars in this class and other
2283                 // classes will be fine, this is the best we can do short of
2284                 // crashing.
2285                 if (ClangASTContext::StartTagDeclarationDefinition(
2286                         base_class_type)) {
2287                   ClangASTContext::CompleteTagDeclarationDefinition(
2288                       base_class_type);
2289                 }
2290               }
2291             }
2292           }
2293           m_ast.SetBaseClassesForClassType(clang_type.GetOpaqueQualType(),
2294                                            &base_classes.front(),
2295                                            base_classes.size());
2296 
2297           // Clang will copy each CXXBaseSpecifier in "base_classes" so we have
2298           // to free them all.
2299           ClangASTContext::DeleteBaseClassSpecifiers(&base_classes.front(),
2300                                                      base_classes.size());
2301         }
2302       }
2303     }
2304 
2305     m_ast.AddMethodOverridesForCXXRecordType(clang_type.GetOpaqueQualType());
2306     ClangASTContext::BuildIndirectFields(clang_type);
2307     ClangASTContext::CompleteTagDeclarationDefinition(clang_type);
2308 
2309     if (!layout_info.field_offsets.empty() ||
2310         !layout_info.base_offsets.empty() ||
2311         !layout_info.vbase_offsets.empty()) {
2312       if (type)
2313         layout_info.bit_size = type->GetByteSize() * 8;
2314       if (layout_info.bit_size == 0)
2315         layout_info.bit_size =
2316             die.GetAttributeValueAsUnsigned(DW_AT_byte_size, 0) * 8;
2317 
2318       clang::CXXRecordDecl *record_decl =
2319           m_ast.GetAsCXXRecordDecl(clang_type.GetOpaqueQualType());
2320       if (record_decl) {
2321         if (log) {
2322           ModuleSP module_sp = dwarf->GetObjectFile()->GetModule();
2323 
2324           if (module_sp) {
2325             module_sp->LogMessage(
2326                 log,
2327                 "ClangASTContext::CompleteTypeFromDWARF (clang_type = %p) "
2328                 "caching layout info for record_decl = %p, bit_size = %" PRIu64
2329                 ", alignment = %" PRIu64
2330                 ", field_offsets[%u], base_offsets[%u], vbase_offsets[%u])",
2331                 static_cast<void *>(clang_type.GetOpaqueQualType()),
2332                 static_cast<void *>(record_decl), layout_info.bit_size,
2333                 layout_info.alignment,
2334                 static_cast<uint32_t>(layout_info.field_offsets.size()),
2335                 static_cast<uint32_t>(layout_info.base_offsets.size()),
2336                 static_cast<uint32_t>(layout_info.vbase_offsets.size()));
2337 
2338             uint32_t idx;
2339             {
2340               llvm::DenseMap<const clang::FieldDecl *, uint64_t>::const_iterator
2341                   pos,
2342                   end = layout_info.field_offsets.end();
2343               for (idx = 0, pos = layout_info.field_offsets.begin(); pos != end;
2344                    ++pos, ++idx) {
2345                 module_sp->LogMessage(
2346                     log, "ClangASTContext::CompleteTypeFromDWARF (clang_type = "
2347                          "%p) field[%u] = { bit_offset=%u, name='%s' }",
2348                     static_cast<void *>(clang_type.GetOpaqueQualType()), idx,
2349                     static_cast<uint32_t>(pos->second),
2350                     pos->first->getNameAsString().c_str());
2351               }
2352             }
2353 
2354             {
2355               llvm::DenseMap<const clang::CXXRecordDecl *,
2356                              clang::CharUnits>::const_iterator base_pos,
2357                   base_end = layout_info.base_offsets.end();
2358               for (idx = 0, base_pos = layout_info.base_offsets.begin();
2359                    base_pos != base_end; ++base_pos, ++idx) {
2360                 module_sp->LogMessage(
2361                     log, "ClangASTContext::CompleteTypeFromDWARF (clang_type = "
2362                          "%p) base[%u] = { byte_offset=%u, name='%s' }",
2363                     clang_type.GetOpaqueQualType(), idx,
2364                     (uint32_t)base_pos->second.getQuantity(),
2365                     base_pos->first->getNameAsString().c_str());
2366               }
2367             }
2368             {
2369               llvm::DenseMap<const clang::CXXRecordDecl *,
2370                              clang::CharUnits>::const_iterator vbase_pos,
2371                   vbase_end = layout_info.vbase_offsets.end();
2372               for (idx = 0, vbase_pos = layout_info.vbase_offsets.begin();
2373                    vbase_pos != vbase_end; ++vbase_pos, ++idx) {
2374                 module_sp->LogMessage(
2375                     log, "ClangASTContext::CompleteTypeFromDWARF (clang_type = "
2376                          "%p) vbase[%u] = { byte_offset=%u, name='%s' }",
2377                     static_cast<void *>(clang_type.GetOpaqueQualType()), idx,
2378                     static_cast<uint32_t>(vbase_pos->second.getQuantity()),
2379                     vbase_pos->first->getNameAsString().c_str());
2380               }
2381             }
2382           }
2383         }
2384         GetClangASTImporter().InsertRecordDecl(record_decl, layout_info);
2385       }
2386     }
2387   }
2388 
2389     return (bool)clang_type;
2390 
2391   case DW_TAG_enumeration_type:
2392     if (ClangASTContext::StartTagDeclarationDefinition(clang_type)) {
2393       if (die.HasChildren()) {
2394         SymbolContext sc(die.GetLLDBCompileUnit());
2395         bool is_signed = false;
2396         clang_type.IsIntegerType(is_signed);
2397         ParseChildEnumerators(sc, clang_type, is_signed, type->GetByteSize(),
2398                               die);
2399       }
2400       ClangASTContext::CompleteTagDeclarationDefinition(clang_type);
2401     }
2402     return (bool)clang_type;
2403 
2404   default:
2405     assert(false && "not a forward clang type decl!");
2406     break;
2407   }
2408 
2409   return false;
2410 }
2411 
2412 std::vector<DWARFDIE> DWARFASTParserClang::GetDIEForDeclContext(
2413     lldb_private::CompilerDeclContext decl_context) {
2414   std::vector<DWARFDIE> result;
2415   for (auto it = m_decl_ctx_to_die.find(
2416            (clang::DeclContext *)decl_context.GetOpaqueDeclContext());
2417        it != m_decl_ctx_to_die.end(); it++)
2418     result.push_back(it->second);
2419   return result;
2420 }
2421 
2422 CompilerDecl DWARFASTParserClang::GetDeclForUIDFromDWARF(const DWARFDIE &die) {
2423   clang::Decl *clang_decl = GetClangDeclForDIE(die);
2424   if (clang_decl != nullptr)
2425     return CompilerDecl(&m_ast, clang_decl);
2426   return CompilerDecl();
2427 }
2428 
2429 CompilerDeclContext
2430 DWARFASTParserClang::GetDeclContextForUIDFromDWARF(const DWARFDIE &die) {
2431   clang::DeclContext *clang_decl_ctx = GetClangDeclContextForDIE(die);
2432   if (clang_decl_ctx)
2433     return CompilerDeclContext(&m_ast, clang_decl_ctx);
2434   return CompilerDeclContext();
2435 }
2436 
2437 CompilerDeclContext
2438 DWARFASTParserClang::GetDeclContextContainingUIDFromDWARF(const DWARFDIE &die) {
2439   clang::DeclContext *clang_decl_ctx =
2440       GetClangDeclContextContainingDIE(die, nullptr);
2441   if (clang_decl_ctx)
2442     return CompilerDeclContext(&m_ast, clang_decl_ctx);
2443   return CompilerDeclContext();
2444 }
2445 
2446 size_t DWARFASTParserClang::ParseChildEnumerators(
2447     const SymbolContext &sc, lldb_private::CompilerType &clang_type,
2448     bool is_signed, uint32_t enumerator_byte_size, const DWARFDIE &parent_die) {
2449   if (!parent_die)
2450     return 0;
2451 
2452   size_t enumerators_added = 0;
2453 
2454   for (DWARFDIE die = parent_die.GetFirstChild(); die.IsValid();
2455        die = die.GetSibling()) {
2456     const dw_tag_t tag = die.Tag();
2457     if (tag == DW_TAG_enumerator) {
2458       DWARFAttributes attributes;
2459       const size_t num_child_attributes = die.GetAttributes(attributes);
2460       if (num_child_attributes > 0) {
2461         const char *name = NULL;
2462         bool got_value = false;
2463         int64_t enum_value = 0;
2464         Declaration decl;
2465 
2466         uint32_t i;
2467         for (i = 0; i < num_child_attributes; ++i) {
2468           const dw_attr_t attr = attributes.AttributeAtIndex(i);
2469           DWARFFormValue form_value;
2470           if (attributes.ExtractFormValueAtIndex(i, form_value)) {
2471             switch (attr) {
2472             case DW_AT_const_value:
2473               got_value = true;
2474               if (is_signed)
2475                 enum_value = form_value.Signed();
2476               else
2477                 enum_value = form_value.Unsigned();
2478               break;
2479 
2480             case DW_AT_name:
2481               name = form_value.AsCString();
2482               break;
2483 
2484             case DW_AT_description:
2485             default:
2486             case DW_AT_decl_file:
2487               decl.SetFile(sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(
2488                   form_value.Unsigned()));
2489               break;
2490             case DW_AT_decl_line:
2491               decl.SetLine(form_value.Unsigned());
2492               break;
2493             case DW_AT_decl_column:
2494               decl.SetColumn(form_value.Unsigned());
2495               break;
2496             case DW_AT_sibling:
2497               break;
2498             }
2499           }
2500         }
2501 
2502         if (name && name[0] && got_value) {
2503           m_ast.AddEnumerationValueToEnumerationType(
2504               clang_type.GetOpaqueQualType(),
2505               m_ast.GetEnumerationIntegerType(clang_type.GetOpaqueQualType()),
2506               decl, name, enum_value, enumerator_byte_size * 8);
2507           ++enumerators_added;
2508         }
2509       }
2510     }
2511   }
2512   return enumerators_added;
2513 }
2514 
2515 #if defined(LLDB_CONFIGURATION_DEBUG) || defined(LLDB_CONFIGURATION_RELEASE)
2516 
2517 class DIEStack {
2518 public:
2519   void Push(const DWARFDIE &die) { m_dies.push_back(die); }
2520 
2521   void LogDIEs(Log *log) {
2522     StreamString log_strm;
2523     const size_t n = m_dies.size();
2524     log_strm.Printf("DIEStack[%" PRIu64 "]:\n", (uint64_t)n);
2525     for (size_t i = 0; i < n; i++) {
2526       std::string qualified_name;
2527       const DWARFDIE &die = m_dies[i];
2528       die.GetQualifiedName(qualified_name);
2529       log_strm.Printf("[%" PRIu64 "] 0x%8.8x: %s name='%s'\n", (uint64_t)i,
2530                       die.GetOffset(), die.GetTagAsCString(),
2531                       qualified_name.c_str());
2532     }
2533     log->PutCString(log_strm.GetData());
2534   }
2535   void Pop() { m_dies.pop_back(); }
2536 
2537   class ScopedPopper {
2538   public:
2539     ScopedPopper(DIEStack &die_stack)
2540         : m_die_stack(die_stack), m_valid(false) {}
2541 
2542     void Push(const DWARFDIE &die) {
2543       m_valid = true;
2544       m_die_stack.Push(die);
2545     }
2546 
2547     ~ScopedPopper() {
2548       if (m_valid)
2549         m_die_stack.Pop();
2550     }
2551 
2552   protected:
2553     DIEStack &m_die_stack;
2554     bool m_valid;
2555   };
2556 
2557 protected:
2558   typedef std::vector<DWARFDIE> Stack;
2559   Stack m_dies;
2560 };
2561 #endif
2562 
2563 Function *DWARFASTParserClang::ParseFunctionFromDWARF(const SymbolContext &sc,
2564                                                       const DWARFDIE &die) {
2565   DWARFRangeList func_ranges;
2566   const char *name = NULL;
2567   const char *mangled = NULL;
2568   int decl_file = 0;
2569   int decl_line = 0;
2570   int decl_column = 0;
2571   int call_file = 0;
2572   int call_line = 0;
2573   int call_column = 0;
2574   DWARFExpression frame_base(die.GetCU());
2575 
2576   const dw_tag_t tag = die.Tag();
2577 
2578   if (tag != DW_TAG_subprogram)
2579     return NULL;
2580 
2581   if (die.GetDIENamesAndRanges(name, mangled, func_ranges, decl_file, decl_line,
2582                                decl_column, call_file, call_line, call_column,
2583                                &frame_base)) {
2584 
2585     // Union of all ranges in the function DIE (if the function is
2586     // discontiguous)
2587     AddressRange func_range;
2588     lldb::addr_t lowest_func_addr = func_ranges.GetMinRangeBase(0);
2589     lldb::addr_t highest_func_addr = func_ranges.GetMaxRangeEnd(0);
2590     if (lowest_func_addr != LLDB_INVALID_ADDRESS &&
2591         lowest_func_addr <= highest_func_addr) {
2592       ModuleSP module_sp(die.GetModule());
2593       func_range.GetBaseAddress().ResolveAddressUsingFileSections(
2594           lowest_func_addr, module_sp->GetSectionList());
2595       if (func_range.GetBaseAddress().IsValid())
2596         func_range.SetByteSize(highest_func_addr - lowest_func_addr);
2597     }
2598 
2599     if (func_range.GetBaseAddress().IsValid()) {
2600       Mangled func_name;
2601       if (mangled)
2602         func_name.SetValue(ConstString(mangled), true);
2603       else if ((die.GetParent().Tag() == DW_TAG_compile_unit ||
2604                 die.GetParent().Tag() == DW_TAG_partial_unit) &&
2605                Language::LanguageIsCPlusPlus(die.GetLanguage()) && name &&
2606                strcmp(name, "main") != 0) {
2607         // If the mangled name is not present in the DWARF, generate the
2608         // demangled name using the decl context. We skip if the function is
2609         // "main" as its name is never mangled.
2610         bool is_static = false;
2611         bool is_variadic = false;
2612         bool has_template_params = false;
2613         unsigned type_quals = 0;
2614         std::vector<CompilerType> param_types;
2615         std::vector<clang::ParmVarDecl *> param_decls;
2616         DWARFDeclContext decl_ctx;
2617         StreamString sstr;
2618 
2619         die.GetDWARFDeclContext(decl_ctx);
2620         sstr << decl_ctx.GetQualifiedName();
2621 
2622         clang::DeclContext *containing_decl_ctx =
2623             GetClangDeclContextContainingDIE(die, nullptr);
2624         ParseChildParameters(sc, containing_decl_ctx, die, true, is_static,
2625                              is_variadic, has_template_params, param_types,
2626                              param_decls, type_quals);
2627         sstr << "(";
2628         for (size_t i = 0; i < param_types.size(); i++) {
2629           if (i > 0)
2630             sstr << ", ";
2631           sstr << param_types[i].GetTypeName();
2632         }
2633         if (is_variadic)
2634           sstr << ", ...";
2635         sstr << ")";
2636         if (type_quals & clang::Qualifiers::Const)
2637           sstr << " const";
2638 
2639         func_name.SetValue(ConstString(sstr.GetString()), false);
2640       } else
2641         func_name.SetValue(ConstString(name), false);
2642 
2643       FunctionSP func_sp;
2644       std::unique_ptr<Declaration> decl_ap;
2645       if (decl_file != 0 || decl_line != 0 || decl_column != 0)
2646         decl_ap.reset(new Declaration(
2647             sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(decl_file),
2648             decl_line, decl_column));
2649 
2650       SymbolFileDWARF *dwarf = die.GetDWARF();
2651       // Supply the type _only_ if it has already been parsed
2652       Type *func_type = dwarf->GetDIEToType().lookup(die.GetDIE());
2653 
2654       assert(func_type == NULL || func_type != DIE_IS_BEING_PARSED);
2655 
2656       if (dwarf->FixupAddress(func_range.GetBaseAddress())) {
2657         const user_id_t func_user_id = die.GetID();
2658         func_sp.reset(new Function(sc.comp_unit,
2659                                    func_user_id, // UserID is the DIE offset
2660                                    func_user_id, func_name, func_type,
2661                                    func_range)); // first address range
2662 
2663         if (func_sp.get() != NULL) {
2664           if (frame_base.IsValid())
2665             func_sp->GetFrameBaseExpression() = frame_base;
2666           sc.comp_unit->AddFunction(func_sp);
2667           return func_sp.get();
2668         }
2669       }
2670     }
2671   }
2672   return NULL;
2673 }
2674 
2675 bool DWARFASTParserClang::ParseChildMembers(
2676     const SymbolContext &sc, const DWARFDIE &parent_die,
2677     CompilerType &class_clang_type, const LanguageType class_language,
2678     std::vector<clang::CXXBaseSpecifier *> &base_classes,
2679     std::vector<int> &member_accessibilities,
2680     DWARFDIECollection &member_function_dies,
2681     DelayedPropertyList &delayed_properties, AccessType &default_accessibility,
2682     bool &is_a_class, ClangASTImporter::LayoutInfo &layout_info) {
2683   if (!parent_die)
2684     return 0;
2685 
2686   // Get the parent byte size so we can verify any members will fit
2687   const uint64_t parent_byte_size =
2688       parent_die.GetAttributeValueAsUnsigned(DW_AT_byte_size, UINT64_MAX);
2689   const uint64_t parent_bit_size =
2690       parent_byte_size == UINT64_MAX ? UINT64_MAX : parent_byte_size * 8;
2691 
2692   uint32_t member_idx = 0;
2693   BitfieldInfo last_field_info;
2694 
2695   ModuleSP module_sp = parent_die.GetDWARF()->GetObjectFile()->GetModule();
2696   ClangASTContext *ast =
2697       llvm::dyn_cast_or_null<ClangASTContext>(class_clang_type.GetTypeSystem());
2698   if (ast == nullptr)
2699     return 0;
2700 
2701   for (DWARFDIE die = parent_die.GetFirstChild(); die.IsValid();
2702        die = die.GetSibling()) {
2703     dw_tag_t tag = die.Tag();
2704 
2705     switch (tag) {
2706     case DW_TAG_member:
2707     case DW_TAG_APPLE_property: {
2708       DWARFAttributes attributes;
2709       const size_t num_attributes = die.GetAttributes(attributes);
2710       if (num_attributes > 0) {
2711         Declaration decl;
2712         // DWARFExpression location;
2713         const char *name = NULL;
2714         const char *prop_name = NULL;
2715         const char *prop_getter_name = NULL;
2716         const char *prop_setter_name = NULL;
2717         uint32_t prop_attributes = 0;
2718 
2719         bool is_artificial = false;
2720         DWARFFormValue encoding_form;
2721         AccessType accessibility = eAccessNone;
2722         uint32_t member_byte_offset =
2723             (parent_die.Tag() == DW_TAG_union_type) ? 0 : UINT32_MAX;
2724         size_t byte_size = 0;
2725         int64_t bit_offset = 0;
2726         uint64_t data_bit_offset = UINT64_MAX;
2727         size_t bit_size = 0;
2728         bool is_external =
2729             false; // On DW_TAG_members, this means the member is static
2730         uint32_t i;
2731         for (i = 0; i < num_attributes && !is_artificial; ++i) {
2732           const dw_attr_t attr = attributes.AttributeAtIndex(i);
2733           DWARFFormValue form_value;
2734           if (attributes.ExtractFormValueAtIndex(i, form_value)) {
2735             switch (attr) {
2736             case DW_AT_decl_file:
2737               decl.SetFile(sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(
2738                   form_value.Unsigned()));
2739               break;
2740             case DW_AT_decl_line:
2741               decl.SetLine(form_value.Unsigned());
2742               break;
2743             case DW_AT_decl_column:
2744               decl.SetColumn(form_value.Unsigned());
2745               break;
2746             case DW_AT_name:
2747               name = form_value.AsCString();
2748               break;
2749             case DW_AT_type:
2750               encoding_form = form_value;
2751               break;
2752             case DW_AT_bit_offset:
2753               bit_offset = form_value.Signed();
2754               break;
2755             case DW_AT_bit_size:
2756               bit_size = form_value.Unsigned();
2757               break;
2758             case DW_AT_byte_size:
2759               byte_size = form_value.Unsigned();
2760               break;
2761             case DW_AT_data_bit_offset:
2762               data_bit_offset = form_value.Unsigned();
2763               break;
2764             case DW_AT_data_member_location:
2765               if (form_value.BlockData()) {
2766                 Value initialValue(0);
2767                 Value memberOffset(0);
2768                 const DWARFDataExtractor &debug_info_data = die.GetData();
2769                 uint32_t block_length = form_value.Unsigned();
2770                 uint32_t block_offset =
2771                     form_value.BlockData() - debug_info_data.GetDataStart();
2772                 if (DWARFExpression::Evaluate(
2773                         nullptr, // ExecutionContext *
2774                         nullptr, // RegisterContext *
2775                         module_sp, debug_info_data, die.GetCU(), block_offset,
2776                         block_length, eRegisterKindDWARF, &initialValue,
2777                         nullptr, memberOffset, nullptr)) {
2778                   member_byte_offset = memberOffset.ResolveValue(NULL).UInt();
2779                 }
2780               } else {
2781                 // With DWARF 3 and later, if the value is an integer constant,
2782                 // this form value is the offset in bytes from the beginning of
2783                 // the containing entity.
2784                 member_byte_offset = form_value.Unsigned();
2785               }
2786               break;
2787 
2788             case DW_AT_accessibility:
2789               accessibility = DW_ACCESS_to_AccessType(form_value.Unsigned());
2790               break;
2791             case DW_AT_artificial:
2792               is_artificial = form_value.Boolean();
2793               break;
2794             case DW_AT_APPLE_property_name:
2795               prop_name = form_value.AsCString();
2796               break;
2797             case DW_AT_APPLE_property_getter:
2798               prop_getter_name = form_value.AsCString();
2799               break;
2800             case DW_AT_APPLE_property_setter:
2801               prop_setter_name = form_value.AsCString();
2802               break;
2803             case DW_AT_APPLE_property_attribute:
2804               prop_attributes = form_value.Unsigned();
2805               break;
2806             case DW_AT_external:
2807               is_external = form_value.Boolean();
2808               break;
2809 
2810             default:
2811             case DW_AT_declaration:
2812             case DW_AT_description:
2813             case DW_AT_mutable:
2814             case DW_AT_visibility:
2815             case DW_AT_sibling:
2816               break;
2817             }
2818           }
2819         }
2820 
2821         if (prop_name) {
2822           ConstString fixed_getter;
2823           ConstString fixed_setter;
2824 
2825           // Check if the property getter/setter were provided as full names.
2826           // We want basenames, so we extract them.
2827 
2828           if (prop_getter_name && prop_getter_name[0] == '-') {
2829             ObjCLanguage::MethodName prop_getter_method(prop_getter_name, true);
2830             prop_getter_name = prop_getter_method.GetSelector().GetCString();
2831           }
2832 
2833           if (prop_setter_name && prop_setter_name[0] == '-') {
2834             ObjCLanguage::MethodName prop_setter_method(prop_setter_name, true);
2835             prop_setter_name = prop_setter_method.GetSelector().GetCString();
2836           }
2837 
2838           // If the names haven't been provided, they need to be filled in.
2839 
2840           if (!prop_getter_name) {
2841             prop_getter_name = prop_name;
2842           }
2843           if (!prop_setter_name && prop_name[0] &&
2844               !(prop_attributes & DW_APPLE_PROPERTY_readonly)) {
2845             StreamString ss;
2846 
2847             ss.Printf("set%c%s:", toupper(prop_name[0]), &prop_name[1]);
2848 
2849             fixed_setter.SetString(ss.GetString());
2850             prop_setter_name = fixed_setter.GetCString();
2851           }
2852         }
2853 
2854         // Clang has a DWARF generation bug where sometimes it represents
2855         // fields that are references with bad byte size and bit size/offset
2856         // information such as:
2857         //
2858         //  DW_AT_byte_size( 0x00 )
2859         //  DW_AT_bit_size( 0x40 )
2860         //  DW_AT_bit_offset( 0xffffffffffffffc0 )
2861         //
2862         // So check the bit offset to make sure it is sane, and if the values
2863         // are not sane, remove them. If we don't do this then we will end up
2864         // with a crash if we try to use this type in an expression when clang
2865         // becomes unhappy with its recycled debug info.
2866 
2867         if (byte_size == 0 && bit_offset < 0) {
2868           bit_size = 0;
2869           bit_offset = 0;
2870         }
2871 
2872         // FIXME: Make Clang ignore Objective-C accessibility for expressions
2873         if (class_language == eLanguageTypeObjC ||
2874             class_language == eLanguageTypeObjC_plus_plus)
2875           accessibility = eAccessNone;
2876 
2877         // Handle static members
2878         if (is_external && member_byte_offset == UINT32_MAX) {
2879           Type *var_type = die.ResolveTypeUID(DIERef(encoding_form));
2880 
2881           if (var_type) {
2882             if (accessibility == eAccessNone)
2883               accessibility = eAccessPublic;
2884             ClangASTContext::AddVariableToRecordType(
2885                 class_clang_type, name, var_type->GetLayoutCompilerType(),
2886                 accessibility);
2887           }
2888           break;
2889         }
2890 
2891         if (is_artificial == false) {
2892           Type *member_type = die.ResolveTypeUID(DIERef(encoding_form));
2893 
2894           clang::FieldDecl *field_decl = NULL;
2895           if (tag == DW_TAG_member) {
2896             if (member_type) {
2897               if (accessibility == eAccessNone)
2898                 accessibility = default_accessibility;
2899               member_accessibilities.push_back(accessibility);
2900 
2901               uint64_t field_bit_offset =
2902                   (member_byte_offset == UINT32_MAX ? 0
2903                                                     : (member_byte_offset * 8));
2904               if (bit_size > 0) {
2905 
2906                 BitfieldInfo this_field_info;
2907                 this_field_info.bit_offset = field_bit_offset;
2908                 this_field_info.bit_size = bit_size;
2909 
2910                 /////////////////////////////////////////////////////////////
2911                 // How to locate a field given the DWARF debug information
2912                 //
2913                 // AT_byte_size indicates the size of the word in which the bit
2914                 // offset must be interpreted.
2915                 //
2916                 // AT_data_member_location indicates the byte offset of the
2917                 // word from the base address of the structure.
2918                 //
2919                 // AT_bit_offset indicates how many bits into the word
2920                 // (according to the host endianness) the low-order bit of the
2921                 // field starts.  AT_bit_offset can be negative.
2922                 //
2923                 // AT_bit_size indicates the size of the field in bits.
2924                 /////////////////////////////////////////////////////////////
2925 
2926                 if (data_bit_offset != UINT64_MAX) {
2927                   this_field_info.bit_offset = data_bit_offset;
2928                 } else {
2929                   if (byte_size == 0)
2930                     byte_size = member_type->GetByteSize();
2931 
2932                   ObjectFile *objfile = die.GetDWARF()->GetObjectFile();
2933                   if (objfile->GetByteOrder() == eByteOrderLittle) {
2934                     this_field_info.bit_offset += byte_size * 8;
2935                     this_field_info.bit_offset -= (bit_offset + bit_size);
2936                   } else {
2937                     this_field_info.bit_offset += bit_offset;
2938                   }
2939                 }
2940 
2941                 if ((this_field_info.bit_offset >= parent_bit_size) ||
2942                     !last_field_info.NextBitfieldOffsetIsValid(
2943                         this_field_info.bit_offset)) {
2944                   ObjectFile *objfile = die.GetDWARF()->GetObjectFile();
2945                   objfile->GetModule()->ReportWarning(
2946                       "0x%8.8" PRIx64 ": %s bitfield named \"%s\" has invalid "
2947                                       "bit offset (0x%8.8" PRIx64
2948                       ") member will be ignored. Please file a bug against the "
2949                       "compiler and include the preprocessed output for %s\n",
2950                       die.GetID(), DW_TAG_value_to_name(tag), name,
2951                       this_field_info.bit_offset,
2952                       sc.comp_unit ? sc.comp_unit->GetPath().c_str()
2953                                    : "the source file");
2954                   this_field_info.Clear();
2955                   continue;
2956                 }
2957 
2958                 // Update the field bit offset we will report for layout
2959                 field_bit_offset = this_field_info.bit_offset;
2960 
2961                 // If the member to be emitted did not start on a character
2962                 // boundary and there is empty space between the last field and
2963                 // this one, then we need to emit an anonymous member filling
2964                 // up the space up to its start.  There are three cases here:
2965                 //
2966                 // 1 If the previous member ended on a character boundary, then
2967                 // we can emit an
2968                 //   anonymous member starting at the most recent character
2969                 //   boundary.
2970                 //
2971                 // 2 If the previous member did not end on a character boundary
2972                 // and the distance
2973                 //   from the end of the previous member to the current member
2974                 //   is less than a
2975                 //   word width, then we can emit an anonymous member starting
2976                 //   right after the
2977                 //   previous member and right before this member.
2978                 //
2979                 // 3 If the previous member did not end on a character boundary
2980                 // and the distance
2981                 //   from the end of the previous member to the current member
2982                 //   is greater than
2983                 //   or equal a word width, then we act as in Case 1.
2984 
2985                 const uint64_t character_width = 8;
2986                 const uint64_t word_width = 32;
2987 
2988                 // Objective-C has invalid DW_AT_bit_offset values in older
2989                 // versions of clang, so we have to be careful and only insert
2990                 // unnamed bitfields if we have a new enough clang.
2991                 bool detect_unnamed_bitfields = true;
2992 
2993                 if (class_language == eLanguageTypeObjC ||
2994                     class_language == eLanguageTypeObjC_plus_plus)
2995                   detect_unnamed_bitfields =
2996                       die.GetCU()->Supports_unnamed_objc_bitfields();
2997 
2998                 if (detect_unnamed_bitfields) {
2999                   BitfieldInfo anon_field_info;
3000 
3001                   if ((this_field_info.bit_offset % character_width) !=
3002                       0) // not char aligned
3003                   {
3004                     uint64_t last_field_end = 0;
3005 
3006                     if (last_field_info.IsValid())
3007                       last_field_end =
3008                           last_field_info.bit_offset + last_field_info.bit_size;
3009 
3010                     if (this_field_info.bit_offset != last_field_end) {
3011                       if (((last_field_end % character_width) == 0) || // case 1
3012                           (this_field_info.bit_offset - last_field_end >=
3013                            word_width)) // case 3
3014                       {
3015                         anon_field_info.bit_size =
3016                             this_field_info.bit_offset % character_width;
3017                         anon_field_info.bit_offset =
3018                             this_field_info.bit_offset -
3019                             anon_field_info.bit_size;
3020                       } else // case 2
3021                       {
3022                         anon_field_info.bit_size =
3023                             this_field_info.bit_offset - last_field_end;
3024                         anon_field_info.bit_offset = last_field_end;
3025                       }
3026                     }
3027                   }
3028 
3029                   if (anon_field_info.IsValid()) {
3030                     clang::FieldDecl *unnamed_bitfield_decl =
3031                         ClangASTContext::AddFieldToRecordType(
3032                             class_clang_type, NULL,
3033                             m_ast.GetBuiltinTypeForEncodingAndBitSize(
3034                                 eEncodingSint, word_width),
3035                             accessibility, anon_field_info.bit_size);
3036 
3037                     layout_info.field_offsets.insert(std::make_pair(
3038                         unnamed_bitfield_decl, anon_field_info.bit_offset));
3039                   }
3040                 }
3041                 last_field_info = this_field_info;
3042               } else {
3043                 last_field_info.Clear();
3044               }
3045 
3046               CompilerType member_clang_type =
3047                   member_type->GetLayoutCompilerType();
3048               if (!member_clang_type.IsCompleteType())
3049                 member_clang_type.GetCompleteType();
3050 
3051               {
3052                 // Older versions of clang emit array[0] and array[1] in the
3053                 // same way (<rdar://problem/12566646>). If the current field
3054                 // is at the end of the structure, then there is definitely no
3055                 // room for extra elements and we override the type to
3056                 // array[0].
3057 
3058                 CompilerType member_array_element_type;
3059                 uint64_t member_array_size;
3060                 bool member_array_is_incomplete;
3061 
3062                 if (member_clang_type.IsArrayType(
3063                         &member_array_element_type, &member_array_size,
3064                         &member_array_is_incomplete) &&
3065                     !member_array_is_incomplete) {
3066                   uint64_t parent_byte_size =
3067                       parent_die.GetAttributeValueAsUnsigned(DW_AT_byte_size,
3068                                                              UINT64_MAX);
3069 
3070                   if (member_byte_offset >= parent_byte_size) {
3071                     if (member_array_size != 1 &&
3072                         (member_array_size != 0 ||
3073                          member_byte_offset > parent_byte_size)) {
3074                       module_sp->ReportError(
3075                           "0x%8.8" PRIx64
3076                           ": DW_TAG_member '%s' refers to type 0x%8.8" PRIx64
3077                           " which extends beyond the bounds of 0x%8.8" PRIx64,
3078                           die.GetID(), name, encoding_form.Reference(),
3079                           parent_die.GetID());
3080                     }
3081 
3082                     member_clang_type = m_ast.CreateArrayType(
3083                         member_array_element_type, 0, false);
3084                   }
3085                 }
3086               }
3087 
3088               if (ClangASTContext::IsCXXClassType(member_clang_type) &&
3089                   member_clang_type.GetCompleteType() == false) {
3090                 if (die.GetCU()->GetProducer() == eProducerClang)
3091                   module_sp->ReportError(
3092                       "DWARF DIE at 0x%8.8x (class %s) has a member variable "
3093                       "0x%8.8x (%s) whose type is a forward declaration, not a "
3094                       "complete definition.\nTry compiling the source file "
3095                       "with -fstandalone-debug",
3096                       parent_die.GetOffset(), parent_die.GetName(),
3097                       die.GetOffset(), name);
3098                 else
3099                   module_sp->ReportError(
3100                       "DWARF DIE at 0x%8.8x (class %s) has a member variable "
3101                       "0x%8.8x (%s) whose type is a forward declaration, not a "
3102                       "complete definition.\nPlease file a bug against the "
3103                       "compiler and include the preprocessed output for %s",
3104                       parent_die.GetOffset(), parent_die.GetName(),
3105                       die.GetOffset(), name,
3106                       sc.comp_unit ? sc.comp_unit->GetPath().c_str()
3107                                    : "the source file");
3108                 // We have no choice other than to pretend that the member
3109                 // class is complete. If we don't do this, clang will crash
3110                 // when trying to layout the class. Since we provide layout
3111                 // assistance, all ivars in this class and other classes will
3112                 // be fine, this is the best we can do short of crashing.
3113                 if (ClangASTContext::StartTagDeclarationDefinition(
3114                         member_clang_type)) {
3115                   ClangASTContext::CompleteTagDeclarationDefinition(
3116                       member_clang_type);
3117                 } else {
3118                   module_sp->ReportError(
3119                       "DWARF DIE at 0x%8.8x (class %s) has a member variable "
3120                       "0x%8.8x (%s) whose type claims to be a C++ class but we "
3121                       "were not able to start its definition.\nPlease file a "
3122                       "bug and attach the file at the start of this error "
3123                       "message",
3124                       parent_die.GetOffset(), parent_die.GetName(),
3125                       die.GetOffset(), name);
3126                 }
3127               }
3128 
3129               field_decl = ClangASTContext::AddFieldToRecordType(
3130                   class_clang_type, name, member_clang_type, accessibility,
3131                   bit_size);
3132 
3133               m_ast.SetMetadataAsUserID(field_decl, die.GetID());
3134 
3135               layout_info.field_offsets.insert(
3136                   std::make_pair(field_decl, field_bit_offset));
3137             } else {
3138               if (name)
3139                 module_sp->ReportError(
3140                     "0x%8.8" PRIx64
3141                     ": DW_TAG_member '%s' refers to type 0x%8.8" PRIx64
3142                     " which was unable to be parsed",
3143                     die.GetID(), name, encoding_form.Reference());
3144               else
3145                 module_sp->ReportError(
3146                     "0x%8.8" PRIx64
3147                     ": DW_TAG_member refers to type 0x%8.8" PRIx64
3148                     " which was unable to be parsed",
3149                     die.GetID(), encoding_form.Reference());
3150             }
3151           }
3152 
3153           if (prop_name != NULL && member_type) {
3154             clang::ObjCIvarDecl *ivar_decl = NULL;
3155 
3156             if (field_decl) {
3157               ivar_decl = clang::dyn_cast<clang::ObjCIvarDecl>(field_decl);
3158               assert(ivar_decl != NULL);
3159             }
3160 
3161             ClangASTMetadata metadata;
3162             metadata.SetUserID(die.GetID());
3163             delayed_properties.push_back(DelayedAddObjCClassProperty(
3164                 class_clang_type, prop_name,
3165                 member_type->GetLayoutCompilerType(), ivar_decl,
3166                 prop_setter_name, prop_getter_name, prop_attributes,
3167                 &metadata));
3168 
3169             if (ivar_decl)
3170               m_ast.SetMetadataAsUserID(ivar_decl, die.GetID());
3171           }
3172         }
3173       }
3174       ++member_idx;
3175     } break;
3176 
3177     case DW_TAG_subprogram:
3178       // Let the type parsing code handle this one for us.
3179       member_function_dies.Append(die);
3180       break;
3181 
3182     case DW_TAG_inheritance: {
3183       is_a_class = true;
3184       if (default_accessibility == eAccessNone)
3185         default_accessibility = eAccessPrivate;
3186       // TODO: implement DW_TAG_inheritance type parsing
3187       DWARFAttributes attributes;
3188       const size_t num_attributes = die.GetAttributes(attributes);
3189       if (num_attributes > 0) {
3190         Declaration decl;
3191         DWARFExpression location(die.GetCU());
3192         DWARFFormValue encoding_form;
3193         AccessType accessibility = default_accessibility;
3194         bool is_virtual = false;
3195         bool is_base_of_class = true;
3196         off_t member_byte_offset = 0;
3197         uint32_t i;
3198         for (i = 0; i < num_attributes; ++i) {
3199           const dw_attr_t attr = attributes.AttributeAtIndex(i);
3200           DWARFFormValue form_value;
3201           if (attributes.ExtractFormValueAtIndex(i, form_value)) {
3202             switch (attr) {
3203             case DW_AT_decl_file:
3204               decl.SetFile(sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(
3205                   form_value.Unsigned()));
3206               break;
3207             case DW_AT_decl_line:
3208               decl.SetLine(form_value.Unsigned());
3209               break;
3210             case DW_AT_decl_column:
3211               decl.SetColumn(form_value.Unsigned());
3212               break;
3213             case DW_AT_type:
3214               encoding_form = form_value;
3215               break;
3216             case DW_AT_data_member_location:
3217               if (form_value.BlockData()) {
3218                 Value initialValue(0);
3219                 Value memberOffset(0);
3220                 const DWARFDataExtractor &debug_info_data = die.GetData();
3221                 uint32_t block_length = form_value.Unsigned();
3222                 uint32_t block_offset =
3223                     form_value.BlockData() - debug_info_data.GetDataStart();
3224                 if (DWARFExpression::Evaluate(nullptr, nullptr, module_sp,
3225                                               debug_info_data, die.GetCU(),
3226                                               block_offset, block_length,
3227                                               eRegisterKindDWARF, &initialValue,
3228                                               nullptr, memberOffset, nullptr)) {
3229                   member_byte_offset = memberOffset.ResolveValue(NULL).UInt();
3230                 }
3231               } else {
3232                 // With DWARF 3 and later, if the value is an integer constant,
3233                 // this form value is the offset in bytes from the beginning of
3234                 // the containing entity.
3235                 member_byte_offset = form_value.Unsigned();
3236               }
3237               break;
3238 
3239             case DW_AT_accessibility:
3240               accessibility = DW_ACCESS_to_AccessType(form_value.Unsigned());
3241               break;
3242 
3243             case DW_AT_virtuality:
3244               is_virtual = form_value.Boolean();
3245               break;
3246 
3247             case DW_AT_sibling:
3248               break;
3249 
3250             default:
3251               break;
3252             }
3253           }
3254         }
3255 
3256         Type *base_class_type = die.ResolveTypeUID(DIERef(encoding_form));
3257         if (base_class_type == NULL) {
3258           module_sp->ReportError("0x%8.8x: DW_TAG_inheritance failed to "
3259                                  "resolve the base class at 0x%8.8" PRIx64
3260                                  " from enclosing type 0x%8.8x. \nPlease file "
3261                                  "a bug and attach the file at the start of "
3262                                  "this error message",
3263                                  die.GetOffset(), encoding_form.Reference(),
3264                                  parent_die.GetOffset());
3265           break;
3266         }
3267 
3268         CompilerType base_class_clang_type =
3269             base_class_type->GetFullCompilerType();
3270         assert(base_class_clang_type);
3271         if (class_language == eLanguageTypeObjC) {
3272           ast->SetObjCSuperClass(class_clang_type, base_class_clang_type);
3273         } else {
3274           base_classes.push_back(ast->CreateBaseClassSpecifier(
3275               base_class_clang_type.GetOpaqueQualType(), accessibility,
3276               is_virtual, is_base_of_class));
3277 
3278           if (is_virtual) {
3279             // Do not specify any offset for virtual inheritance. The DWARF
3280             // produced by clang doesn't give us a constant offset, but gives
3281             // us a DWARF expressions that requires an actual object in memory.
3282             // the DW_AT_data_member_location for a virtual base class looks
3283             // like:
3284             //      DW_AT_data_member_location( DW_OP_dup, DW_OP_deref,
3285             //      DW_OP_constu(0x00000018), DW_OP_minus, DW_OP_deref,
3286             //      DW_OP_plus )
3287             // Given this, there is really no valid response we can give to
3288             // clang for virtual base class offsets, and this should eventually
3289             // be removed from LayoutRecordType() in the external
3290             // AST source in clang.
3291           } else {
3292             layout_info.base_offsets.insert(std::make_pair(
3293                 ast->GetAsCXXRecordDecl(
3294                     base_class_clang_type.GetOpaqueQualType()),
3295                 clang::CharUnits::fromQuantity(member_byte_offset)));
3296           }
3297         }
3298       }
3299     } break;
3300 
3301     default:
3302       break;
3303     }
3304   }
3305 
3306   return true;
3307 }
3308 
3309 size_t DWARFASTParserClang::ParseChildParameters(
3310     const SymbolContext &sc, clang::DeclContext *containing_decl_ctx,
3311     const DWARFDIE &parent_die, bool skip_artificial, bool &is_static,
3312     bool &is_variadic, bool &has_template_params,
3313     std::vector<CompilerType> &function_param_types,
3314     std::vector<clang::ParmVarDecl *> &function_param_decls,
3315     unsigned &type_quals) {
3316   if (!parent_die)
3317     return 0;
3318 
3319   size_t arg_idx = 0;
3320   for (DWARFDIE die = parent_die.GetFirstChild(); die.IsValid();
3321        die = die.GetSibling()) {
3322     const dw_tag_t tag = die.Tag();
3323     switch (tag) {
3324     case DW_TAG_formal_parameter: {
3325       DWARFAttributes attributes;
3326       const size_t num_attributes = die.GetAttributes(attributes);
3327       if (num_attributes > 0) {
3328         const char *name = NULL;
3329         Declaration decl;
3330         DWARFFormValue param_type_die_form;
3331         bool is_artificial = false;
3332         // one of None, Auto, Register, Extern, Static, PrivateExtern
3333 
3334         clang::StorageClass storage = clang::SC_None;
3335         uint32_t i;
3336         for (i = 0; i < num_attributes; ++i) {
3337           const dw_attr_t attr = attributes.AttributeAtIndex(i);
3338           DWARFFormValue form_value;
3339           if (attributes.ExtractFormValueAtIndex(i, form_value)) {
3340             switch (attr) {
3341             case DW_AT_decl_file:
3342               decl.SetFile(sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(
3343                   form_value.Unsigned()));
3344               break;
3345             case DW_AT_decl_line:
3346               decl.SetLine(form_value.Unsigned());
3347               break;
3348             case DW_AT_decl_column:
3349               decl.SetColumn(form_value.Unsigned());
3350               break;
3351             case DW_AT_name:
3352               name = form_value.AsCString();
3353               break;
3354             case DW_AT_type:
3355               param_type_die_form = form_value;
3356               break;
3357             case DW_AT_artificial:
3358               is_artificial = form_value.Boolean();
3359               break;
3360             case DW_AT_location:
3361             case DW_AT_const_value:
3362             case DW_AT_default_value:
3363             case DW_AT_description:
3364             case DW_AT_endianity:
3365             case DW_AT_is_optional:
3366             case DW_AT_segment:
3367             case DW_AT_variable_parameter:
3368             default:
3369             case DW_AT_abstract_origin:
3370             case DW_AT_sibling:
3371               break;
3372             }
3373           }
3374         }
3375 
3376         bool skip = false;
3377         if (skip_artificial && is_artificial) {
3378           // In order to determine if a C++ member function is "const" we
3379           // have to look at the const-ness of "this"...
3380           if (arg_idx == 0 &&
3381               DeclKindIsCXXClass(containing_decl_ctx->getDeclKind()) &&
3382               // Often times compilers omit the "this" name for the
3383               // specification DIEs, so we can't rely upon the name being in
3384               // the formal parameter DIE...
3385               (name == NULL || ::strcmp(name, "this") == 0)) {
3386             Type *this_type = die.ResolveTypeUID(DIERef(param_type_die_form));
3387             if (this_type) {
3388               uint32_t encoding_mask = this_type->GetEncodingMask();
3389               if (encoding_mask & Type::eEncodingIsPointerUID) {
3390                 is_static = false;
3391 
3392                 if (encoding_mask & (1u << Type::eEncodingIsConstUID))
3393                   type_quals |= clang::Qualifiers::Const;
3394                 if (encoding_mask & (1u << Type::eEncodingIsVolatileUID))
3395                   type_quals |= clang::Qualifiers::Volatile;
3396               }
3397             }
3398           }
3399           skip = true;
3400         }
3401 
3402         if (!skip) {
3403           Type *type = die.ResolveTypeUID(DIERef(param_type_die_form));
3404           if (type) {
3405             function_param_types.push_back(type->GetForwardCompilerType());
3406 
3407             clang::ParmVarDecl *param_var_decl =
3408                 m_ast.CreateParameterDeclaration(
3409                     name, type->GetForwardCompilerType(), storage);
3410             assert(param_var_decl);
3411             function_param_decls.push_back(param_var_decl);
3412 
3413             m_ast.SetMetadataAsUserID(param_var_decl, die.GetID());
3414           }
3415         }
3416       }
3417       arg_idx++;
3418     } break;
3419 
3420     case DW_TAG_unspecified_parameters:
3421       is_variadic = true;
3422       break;
3423 
3424     case DW_TAG_template_type_parameter:
3425     case DW_TAG_template_value_parameter:
3426     case DW_TAG_GNU_template_parameter_pack:
3427       // The one caller of this was never using the template_param_infos, and
3428       // the local variable was taking up a large amount of stack space in
3429       // SymbolFileDWARF::ParseType() so this was removed. If we ever need the
3430       // template params back, we can add them back.
3431       // ParseTemplateDIE (dwarf_cu, die, template_param_infos);
3432       has_template_params = true;
3433       break;
3434 
3435     default:
3436       break;
3437     }
3438   }
3439   return arg_idx;
3440 }
3441 
3442 void DWARFASTParserClang::ParseChildArrayInfo(
3443     const SymbolContext &sc, const DWARFDIE &parent_die, int64_t &first_index,
3444     std::vector<uint64_t> &element_orders, uint32_t &byte_stride,
3445     uint32_t &bit_stride) {
3446   if (!parent_die)
3447     return;
3448 
3449   for (DWARFDIE die = parent_die.GetFirstChild(); die.IsValid();
3450        die = die.GetSibling()) {
3451     const dw_tag_t tag = die.Tag();
3452     switch (tag) {
3453     case DW_TAG_subrange_type: {
3454       DWARFAttributes attributes;
3455       const size_t num_child_attributes = die.GetAttributes(attributes);
3456       if (num_child_attributes > 0) {
3457         uint64_t num_elements = 0;
3458         uint64_t lower_bound = 0;
3459         uint64_t upper_bound = 0;
3460         bool upper_bound_valid = false;
3461         uint32_t i;
3462         for (i = 0; i < num_child_attributes; ++i) {
3463           const dw_attr_t attr = attributes.AttributeAtIndex(i);
3464           DWARFFormValue form_value;
3465           if (attributes.ExtractFormValueAtIndex(i, form_value)) {
3466             switch (attr) {
3467             case DW_AT_name:
3468               break;
3469 
3470             case DW_AT_count:
3471               num_elements = form_value.Unsigned();
3472               break;
3473 
3474             case DW_AT_bit_stride:
3475               bit_stride = form_value.Unsigned();
3476               break;
3477 
3478             case DW_AT_byte_stride:
3479               byte_stride = form_value.Unsigned();
3480               break;
3481 
3482             case DW_AT_lower_bound:
3483               lower_bound = form_value.Unsigned();
3484               break;
3485 
3486             case DW_AT_upper_bound:
3487               upper_bound_valid = true;
3488               upper_bound = form_value.Unsigned();
3489               break;
3490 
3491             default:
3492             case DW_AT_abstract_origin:
3493             case DW_AT_accessibility:
3494             case DW_AT_allocated:
3495             case DW_AT_associated:
3496             case DW_AT_data_location:
3497             case DW_AT_declaration:
3498             case DW_AT_description:
3499             case DW_AT_sibling:
3500             case DW_AT_threads_scaled:
3501             case DW_AT_type:
3502             case DW_AT_visibility:
3503               break;
3504             }
3505           }
3506         }
3507 
3508         if (num_elements == 0) {
3509           if (upper_bound_valid && upper_bound >= lower_bound)
3510             num_elements = upper_bound - lower_bound + 1;
3511         }
3512 
3513         element_orders.push_back(num_elements);
3514       }
3515     } break;
3516     }
3517   }
3518 }
3519 
3520 Type *DWARFASTParserClang::GetTypeForDIE(const DWARFDIE &die) {
3521   if (die) {
3522     SymbolFileDWARF *dwarf = die.GetDWARF();
3523     DWARFAttributes attributes;
3524     const size_t num_attributes = die.GetAttributes(attributes);
3525     if (num_attributes > 0) {
3526       DWARFFormValue type_die_form;
3527       for (size_t i = 0; i < num_attributes; ++i) {
3528         dw_attr_t attr = attributes.AttributeAtIndex(i);
3529         DWARFFormValue form_value;
3530 
3531         if (attr == DW_AT_type &&
3532             attributes.ExtractFormValueAtIndex(i, form_value))
3533           return dwarf->ResolveTypeUID(dwarf->GetDIE(DIERef(form_value)), true);
3534       }
3535     }
3536   }
3537 
3538   return nullptr;
3539 }
3540 
3541 clang::Decl *DWARFASTParserClang::GetClangDeclForDIE(const DWARFDIE &die) {
3542   if (!die)
3543     return nullptr;
3544 
3545   switch (die.Tag()) {
3546   case DW_TAG_variable:
3547   case DW_TAG_constant:
3548   case DW_TAG_formal_parameter:
3549   case DW_TAG_imported_declaration:
3550   case DW_TAG_imported_module:
3551     break;
3552   default:
3553     return nullptr;
3554   }
3555 
3556   DIEToDeclMap::iterator cache_pos = m_die_to_decl.find(die.GetDIE());
3557   if (cache_pos != m_die_to_decl.end())
3558     return cache_pos->second;
3559 
3560   if (DWARFDIE spec_die = die.GetReferencedDIE(DW_AT_specification)) {
3561     clang::Decl *decl = GetClangDeclForDIE(spec_die);
3562     m_die_to_decl[die.GetDIE()] = decl;
3563     m_decl_to_die[decl].insert(die.GetDIE());
3564     return decl;
3565   }
3566 
3567   if (DWARFDIE abstract_origin_die =
3568           die.GetReferencedDIE(DW_AT_abstract_origin)) {
3569     clang::Decl *decl = GetClangDeclForDIE(abstract_origin_die);
3570     m_die_to_decl[die.GetDIE()] = decl;
3571     m_decl_to_die[decl].insert(die.GetDIE());
3572     return decl;
3573   }
3574 
3575   clang::Decl *decl = nullptr;
3576   switch (die.Tag()) {
3577   case DW_TAG_variable:
3578   case DW_TAG_constant:
3579   case DW_TAG_formal_parameter: {
3580     SymbolFileDWARF *dwarf = die.GetDWARF();
3581     Type *type = GetTypeForDIE(die);
3582     if (dwarf && type) {
3583       const char *name = die.GetName();
3584       clang::DeclContext *decl_context =
3585           ClangASTContext::DeclContextGetAsDeclContext(
3586               dwarf->GetDeclContextContainingUID(die.GetID()));
3587       decl = m_ast.CreateVariableDeclaration(
3588           decl_context, name,
3589           ClangUtil::GetQualType(type->GetForwardCompilerType()));
3590     }
3591     break;
3592   }
3593   case DW_TAG_imported_declaration: {
3594     SymbolFileDWARF *dwarf = die.GetDWARF();
3595     DWARFDIE imported_uid = die.GetAttributeValueAsReferenceDIE(DW_AT_import);
3596     if (imported_uid) {
3597       CompilerDecl imported_decl = imported_uid.GetDecl();
3598       if (imported_decl) {
3599         clang::DeclContext *decl_context =
3600             ClangASTContext::DeclContextGetAsDeclContext(
3601                 dwarf->GetDeclContextContainingUID(die.GetID()));
3602         if (clang::NamedDecl *clang_imported_decl =
3603                 llvm::dyn_cast<clang::NamedDecl>(
3604                     (clang::Decl *)imported_decl.GetOpaqueDecl()))
3605           decl =
3606               m_ast.CreateUsingDeclaration(decl_context, clang_imported_decl);
3607       }
3608     }
3609     break;
3610   }
3611   case DW_TAG_imported_module: {
3612     SymbolFileDWARF *dwarf = die.GetDWARF();
3613     DWARFDIE imported_uid = die.GetAttributeValueAsReferenceDIE(DW_AT_import);
3614 
3615     if (imported_uid) {
3616       CompilerDeclContext imported_decl_ctx = imported_uid.GetDeclContext();
3617       if (imported_decl_ctx) {
3618         clang::DeclContext *decl_context =
3619             ClangASTContext::DeclContextGetAsDeclContext(
3620                 dwarf->GetDeclContextContainingUID(die.GetID()));
3621         if (clang::NamespaceDecl *ns_decl =
3622                 ClangASTContext::DeclContextGetAsNamespaceDecl(
3623                     imported_decl_ctx))
3624           decl = m_ast.CreateUsingDirectiveDeclaration(decl_context, ns_decl);
3625       }
3626     }
3627     break;
3628   }
3629   default:
3630     break;
3631   }
3632 
3633   m_die_to_decl[die.GetDIE()] = decl;
3634   m_decl_to_die[decl].insert(die.GetDIE());
3635 
3636   return decl;
3637 }
3638 
3639 clang::DeclContext *
3640 DWARFASTParserClang::GetClangDeclContextForDIE(const DWARFDIE &die) {
3641   if (die) {
3642     clang::DeclContext *decl_ctx = GetCachedClangDeclContextForDIE(die);
3643     if (decl_ctx)
3644       return decl_ctx;
3645 
3646     bool try_parsing_type = true;
3647     switch (die.Tag()) {
3648     case DW_TAG_compile_unit:
3649     case DW_TAG_partial_unit:
3650       decl_ctx = m_ast.GetTranslationUnitDecl();
3651       try_parsing_type = false;
3652       break;
3653 
3654     case DW_TAG_namespace:
3655       decl_ctx = ResolveNamespaceDIE(die);
3656       try_parsing_type = false;
3657       break;
3658 
3659     case DW_TAG_lexical_block:
3660       decl_ctx = GetDeclContextForBlock(die);
3661       try_parsing_type = false;
3662       break;
3663 
3664     default:
3665       break;
3666     }
3667 
3668     if (decl_ctx == nullptr && try_parsing_type) {
3669       Type *type = die.GetDWARF()->ResolveType(die);
3670       if (type)
3671         decl_ctx = GetCachedClangDeclContextForDIE(die);
3672     }
3673 
3674     if (decl_ctx) {
3675       LinkDeclContextToDIE(decl_ctx, die);
3676       return decl_ctx;
3677     }
3678   }
3679   return nullptr;
3680 }
3681 
3682 static bool IsSubroutine(const DWARFDIE &die) {
3683   switch (die.Tag()) {
3684   case DW_TAG_subprogram:
3685   case DW_TAG_inlined_subroutine:
3686     return true;
3687   default:
3688     return false;
3689   }
3690 }
3691 
3692 static DWARFDIE GetContainingFunctionWithAbstractOrigin(const DWARFDIE &die) {
3693   for (DWARFDIE candidate = die; candidate; candidate = candidate.GetParent()) {
3694     if (IsSubroutine(candidate)) {
3695       if (candidate.GetReferencedDIE(DW_AT_abstract_origin)) {
3696         return candidate;
3697       } else {
3698         return DWARFDIE();
3699       }
3700     }
3701   }
3702   assert(0 && "Shouldn't call GetContainingFunctionWithAbstractOrigin on "
3703               "something not in a function");
3704   return DWARFDIE();
3705 }
3706 
3707 static DWARFDIE FindAnyChildWithAbstractOrigin(const DWARFDIE &context) {
3708   for (DWARFDIE candidate = context.GetFirstChild(); candidate.IsValid();
3709        candidate = candidate.GetSibling()) {
3710     if (candidate.GetReferencedDIE(DW_AT_abstract_origin)) {
3711       return candidate;
3712     }
3713   }
3714   return DWARFDIE();
3715 }
3716 
3717 static DWARFDIE FindFirstChildWithAbstractOrigin(const DWARFDIE &block,
3718                                                  const DWARFDIE &function) {
3719   assert(IsSubroutine(function));
3720   for (DWARFDIE context = block; context != function.GetParent();
3721        context = context.GetParent()) {
3722     assert(!IsSubroutine(context) || context == function);
3723     if (DWARFDIE child = FindAnyChildWithAbstractOrigin(context)) {
3724       return child;
3725     }
3726   }
3727   return DWARFDIE();
3728 }
3729 
3730 clang::DeclContext *
3731 DWARFASTParserClang::GetDeclContextForBlock(const DWARFDIE &die) {
3732   assert(die.Tag() == DW_TAG_lexical_block);
3733   DWARFDIE containing_function_with_abstract_origin =
3734       GetContainingFunctionWithAbstractOrigin(die);
3735   if (!containing_function_with_abstract_origin) {
3736     return (clang::DeclContext *)ResolveBlockDIE(die);
3737   }
3738   DWARFDIE child = FindFirstChildWithAbstractOrigin(
3739       die, containing_function_with_abstract_origin);
3740   CompilerDeclContext decl_context =
3741       GetDeclContextContainingUIDFromDWARF(child);
3742   return (clang::DeclContext *)decl_context.GetOpaqueDeclContext();
3743 }
3744 
3745 clang::BlockDecl *DWARFASTParserClang::ResolveBlockDIE(const DWARFDIE &die) {
3746   if (die && die.Tag() == DW_TAG_lexical_block) {
3747     clang::BlockDecl *decl =
3748         llvm::cast_or_null<clang::BlockDecl>(m_die_to_decl_ctx[die.GetDIE()]);
3749 
3750     if (!decl) {
3751       DWARFDIE decl_context_die;
3752       clang::DeclContext *decl_context =
3753           GetClangDeclContextContainingDIE(die, &decl_context_die);
3754       decl = m_ast.CreateBlockDeclaration(decl_context);
3755 
3756       if (decl)
3757         LinkDeclContextToDIE((clang::DeclContext *)decl, die);
3758     }
3759 
3760     return decl;
3761   }
3762   return nullptr;
3763 }
3764 
3765 clang::NamespaceDecl *
3766 DWARFASTParserClang::ResolveNamespaceDIE(const DWARFDIE &die) {
3767   if (die && die.Tag() == DW_TAG_namespace) {
3768     // See if we already parsed this namespace DIE and associated it with a
3769     // uniqued namespace declaration
3770     clang::NamespaceDecl *namespace_decl =
3771         static_cast<clang::NamespaceDecl *>(m_die_to_decl_ctx[die.GetDIE()]);
3772     if (namespace_decl)
3773       return namespace_decl;
3774     else {
3775       const char *namespace_name = die.GetName();
3776       clang::DeclContext *containing_decl_ctx =
3777           GetClangDeclContextContainingDIE(die, nullptr);
3778       namespace_decl = m_ast.GetUniqueNamespaceDeclaration(namespace_name,
3779                                                            containing_decl_ctx);
3780       Log *log =
3781           nullptr; // (LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO));
3782       if (log) {
3783         SymbolFileDWARF *dwarf = die.GetDWARF();
3784         if (namespace_name) {
3785           dwarf->GetObjectFile()->GetModule()->LogMessage(
3786               log, "ASTContext => %p: 0x%8.8" PRIx64
3787                    ": DW_TAG_namespace with DW_AT_name(\"%s\") => "
3788                    "clang::NamespaceDecl *%p (original = %p)",
3789               static_cast<void *>(m_ast.getASTContext()), die.GetID(),
3790               namespace_name, static_cast<void *>(namespace_decl),
3791               static_cast<void *>(namespace_decl->getOriginalNamespace()));
3792         } else {
3793           dwarf->GetObjectFile()->GetModule()->LogMessage(
3794               log, "ASTContext => %p: 0x%8.8" PRIx64
3795                    ": DW_TAG_namespace (anonymous) => clang::NamespaceDecl *%p "
3796                    "(original = %p)",
3797               static_cast<void *>(m_ast.getASTContext()), die.GetID(),
3798               static_cast<void *>(namespace_decl),
3799               static_cast<void *>(namespace_decl->getOriginalNamespace()));
3800         }
3801       }
3802 
3803       if (namespace_decl)
3804         LinkDeclContextToDIE((clang::DeclContext *)namespace_decl, die);
3805       return namespace_decl;
3806     }
3807   }
3808   return nullptr;
3809 }
3810 
3811 clang::DeclContext *DWARFASTParserClang::GetClangDeclContextContainingDIE(
3812     const DWARFDIE &die, DWARFDIE *decl_ctx_die_copy) {
3813   SymbolFileDWARF *dwarf = die.GetDWARF();
3814 
3815   DWARFDIE decl_ctx_die = dwarf->GetDeclContextDIEContainingDIE(die);
3816 
3817   if (decl_ctx_die_copy)
3818     *decl_ctx_die_copy = decl_ctx_die;
3819 
3820   if (decl_ctx_die) {
3821     clang::DeclContext *clang_decl_ctx =
3822         GetClangDeclContextForDIE(decl_ctx_die);
3823     if (clang_decl_ctx)
3824       return clang_decl_ctx;
3825   }
3826   return m_ast.GetTranslationUnitDecl();
3827 }
3828 
3829 clang::DeclContext *
3830 DWARFASTParserClang::GetCachedClangDeclContextForDIE(const DWARFDIE &die) {
3831   if (die) {
3832     DIEToDeclContextMap::iterator pos = m_die_to_decl_ctx.find(die.GetDIE());
3833     if (pos != m_die_to_decl_ctx.end())
3834       return pos->second;
3835   }
3836   return nullptr;
3837 }
3838 
3839 void DWARFASTParserClang::LinkDeclContextToDIE(clang::DeclContext *decl_ctx,
3840                                                const DWARFDIE &die) {
3841   m_die_to_decl_ctx[die.GetDIE()] = decl_ctx;
3842   // There can be many DIEs for a single decl context
3843   // m_decl_ctx_to_die[decl_ctx].insert(die.GetDIE());
3844   m_decl_ctx_to_die.insert(std::make_pair(decl_ctx, die));
3845 }
3846 
3847 bool DWARFASTParserClang::CopyUniqueClassMethodTypes(
3848     const DWARFDIE &src_class_die, const DWARFDIE &dst_class_die,
3849     lldb_private::Type *class_type, DWARFDIECollection &failures) {
3850   if (!class_type || !src_class_die || !dst_class_die)
3851     return false;
3852   if (src_class_die.Tag() != dst_class_die.Tag())
3853     return false;
3854 
3855   // We need to complete the class type so we can get all of the method types
3856   // parsed so we can then unique those types to their equivalent counterparts
3857   // in "dst_cu" and "dst_class_die"
3858   class_type->GetFullCompilerType();
3859 
3860   DWARFDIE src_die;
3861   DWARFDIE dst_die;
3862   UniqueCStringMap<DWARFDIE> src_name_to_die;
3863   UniqueCStringMap<DWARFDIE> dst_name_to_die;
3864   UniqueCStringMap<DWARFDIE> src_name_to_die_artificial;
3865   UniqueCStringMap<DWARFDIE> dst_name_to_die_artificial;
3866   for (src_die = src_class_die.GetFirstChild(); src_die.IsValid();
3867        src_die = src_die.GetSibling()) {
3868     if (src_die.Tag() == DW_TAG_subprogram) {
3869       // Make sure this is a declaration and not a concrete instance by looking
3870       // for DW_AT_declaration set to 1. Sometimes concrete function instances
3871       // are placed inside the class definitions and shouldn't be included in
3872       // the list of things are are tracking here.
3873       if (src_die.GetAttributeValueAsUnsigned(DW_AT_declaration, 0) == 1) {
3874         const char *src_name = src_die.GetMangledName();
3875         if (src_name) {
3876           ConstString src_const_name(src_name);
3877           if (src_die.GetAttributeValueAsUnsigned(DW_AT_artificial, 0))
3878             src_name_to_die_artificial.Append(src_const_name, src_die);
3879           else
3880             src_name_to_die.Append(src_const_name, src_die);
3881         }
3882       }
3883     }
3884   }
3885   for (dst_die = dst_class_die.GetFirstChild(); dst_die.IsValid();
3886        dst_die = dst_die.GetSibling()) {
3887     if (dst_die.Tag() == DW_TAG_subprogram) {
3888       // Make sure this is a declaration and not a concrete instance by looking
3889       // for DW_AT_declaration set to 1. Sometimes concrete function instances
3890       // are placed inside the class definitions and shouldn't be included in
3891       // the list of things are are tracking here.
3892       if (dst_die.GetAttributeValueAsUnsigned(DW_AT_declaration, 0) == 1) {
3893         const char *dst_name = dst_die.GetMangledName();
3894         if (dst_name) {
3895           ConstString dst_const_name(dst_name);
3896           if (dst_die.GetAttributeValueAsUnsigned(DW_AT_artificial, 0))
3897             dst_name_to_die_artificial.Append(dst_const_name, dst_die);
3898           else
3899             dst_name_to_die.Append(dst_const_name, dst_die);
3900         }
3901       }
3902     }
3903   }
3904   const uint32_t src_size = src_name_to_die.GetSize();
3905   const uint32_t dst_size = dst_name_to_die.GetSize();
3906   Log *log = nullptr; // (LogChannelDWARF::GetLogIfAny(DWARF_LOG_DEBUG_INFO |
3907                       // DWARF_LOG_TYPE_COMPLETION));
3908 
3909   // Is everything kosher so we can go through the members at top speed?
3910   bool fast_path = true;
3911 
3912   if (src_size != dst_size) {
3913     if (src_size != 0 && dst_size != 0) {
3914       if (log)
3915         log->Printf("warning: trying to unique class DIE 0x%8.8x to 0x%8.8x, "
3916                     "but they didn't have the same size (src=%d, dst=%d)",
3917                     src_class_die.GetOffset(), dst_class_die.GetOffset(),
3918                     src_size, dst_size);
3919     }
3920 
3921     fast_path = false;
3922   }
3923 
3924   uint32_t idx;
3925 
3926   if (fast_path) {
3927     for (idx = 0; idx < src_size; ++idx) {
3928       src_die = src_name_to_die.GetValueAtIndexUnchecked(idx);
3929       dst_die = dst_name_to_die.GetValueAtIndexUnchecked(idx);
3930 
3931       if (src_die.Tag() != dst_die.Tag()) {
3932         if (log)
3933           log->Printf("warning: tried to unique class DIE 0x%8.8x to 0x%8.8x, "
3934                       "but 0x%8.8x (%s) tags didn't match 0x%8.8x (%s)",
3935                       src_class_die.GetOffset(), dst_class_die.GetOffset(),
3936                       src_die.GetOffset(), src_die.GetTagAsCString(),
3937                       dst_die.GetOffset(), dst_die.GetTagAsCString());
3938         fast_path = false;
3939       }
3940 
3941       const char *src_name = src_die.GetMangledName();
3942       const char *dst_name = dst_die.GetMangledName();
3943 
3944       // Make sure the names match
3945       if (src_name == dst_name || (strcmp(src_name, dst_name) == 0))
3946         continue;
3947 
3948       if (log)
3949         log->Printf("warning: tried to unique class DIE 0x%8.8x to 0x%8.8x, "
3950                     "but 0x%8.8x (%s) names didn't match 0x%8.8x (%s)",
3951                     src_class_die.GetOffset(), dst_class_die.GetOffset(),
3952                     src_die.GetOffset(), src_name, dst_die.GetOffset(),
3953                     dst_name);
3954 
3955       fast_path = false;
3956     }
3957   }
3958 
3959   DWARFASTParserClang *src_dwarf_ast_parser =
3960       (DWARFASTParserClang *)src_die.GetDWARFParser();
3961   DWARFASTParserClang *dst_dwarf_ast_parser =
3962       (DWARFASTParserClang *)dst_die.GetDWARFParser();
3963 
3964   // Now do the work of linking the DeclContexts and Types.
3965   if (fast_path) {
3966     // We can do this quickly.  Just run across the tables index-for-index
3967     // since we know each node has matching names and tags.
3968     for (idx = 0; idx < src_size; ++idx) {
3969       src_die = src_name_to_die.GetValueAtIndexUnchecked(idx);
3970       dst_die = dst_name_to_die.GetValueAtIndexUnchecked(idx);
3971 
3972       clang::DeclContext *src_decl_ctx =
3973           src_dwarf_ast_parser->m_die_to_decl_ctx[src_die.GetDIE()];
3974       if (src_decl_ctx) {
3975         if (log)
3976           log->Printf("uniquing decl context %p from 0x%8.8x for 0x%8.8x",
3977                       static_cast<void *>(src_decl_ctx), src_die.GetOffset(),
3978                       dst_die.GetOffset());
3979         dst_dwarf_ast_parser->LinkDeclContextToDIE(src_decl_ctx, dst_die);
3980       } else {
3981         if (log)
3982           log->Printf("warning: tried to unique decl context from 0x%8.8x for "
3983                       "0x%8.8x, but none was found",
3984                       src_die.GetOffset(), dst_die.GetOffset());
3985       }
3986 
3987       Type *src_child_type =
3988           dst_die.GetDWARF()->GetDIEToType()[src_die.GetDIE()];
3989       if (src_child_type) {
3990         if (log)
3991           log->Printf(
3992               "uniquing type %p (uid=0x%" PRIx64 ") from 0x%8.8x for 0x%8.8x",
3993               static_cast<void *>(src_child_type), src_child_type->GetID(),
3994               src_die.GetOffset(), dst_die.GetOffset());
3995         dst_die.GetDWARF()->GetDIEToType()[dst_die.GetDIE()] = src_child_type;
3996       } else {
3997         if (log)
3998           log->Printf("warning: tried to unique lldb_private::Type from "
3999                       "0x%8.8x for 0x%8.8x, but none was found",
4000                       src_die.GetOffset(), dst_die.GetOffset());
4001       }
4002     }
4003   } else {
4004     // We must do this slowly.  For each member of the destination, look up a
4005     // member in the source with the same name, check its tag, and unique them
4006     // if everything matches up.  Report failures.
4007 
4008     if (!src_name_to_die.IsEmpty() && !dst_name_to_die.IsEmpty()) {
4009       src_name_to_die.Sort();
4010 
4011       for (idx = 0; idx < dst_size; ++idx) {
4012         ConstString dst_name = dst_name_to_die.GetCStringAtIndex(idx);
4013         dst_die = dst_name_to_die.GetValueAtIndexUnchecked(idx);
4014         src_die = src_name_to_die.Find(dst_name, DWARFDIE());
4015 
4016         if (src_die && (src_die.Tag() == dst_die.Tag())) {
4017           clang::DeclContext *src_decl_ctx =
4018               src_dwarf_ast_parser->m_die_to_decl_ctx[src_die.GetDIE()];
4019           if (src_decl_ctx) {
4020             if (log)
4021               log->Printf("uniquing decl context %p from 0x%8.8x for 0x%8.8x",
4022                           static_cast<void *>(src_decl_ctx),
4023                           src_die.GetOffset(), dst_die.GetOffset());
4024             dst_dwarf_ast_parser->LinkDeclContextToDIE(src_decl_ctx, dst_die);
4025           } else {
4026             if (log)
4027               log->Printf("warning: tried to unique decl context from 0x%8.8x "
4028                           "for 0x%8.8x, but none was found",
4029                           src_die.GetOffset(), dst_die.GetOffset());
4030           }
4031 
4032           Type *src_child_type =
4033               dst_die.GetDWARF()->GetDIEToType()[src_die.GetDIE()];
4034           if (src_child_type) {
4035             if (log)
4036               log->Printf("uniquing type %p (uid=0x%" PRIx64
4037                           ") from 0x%8.8x for 0x%8.8x",
4038                           static_cast<void *>(src_child_type),
4039                           src_child_type->GetID(), src_die.GetOffset(),
4040                           dst_die.GetOffset());
4041             dst_die.GetDWARF()->GetDIEToType()[dst_die.GetDIE()] =
4042                 src_child_type;
4043           } else {
4044             if (log)
4045               log->Printf("warning: tried to unique lldb_private::Type from "
4046                           "0x%8.8x for 0x%8.8x, but none was found",
4047                           src_die.GetOffset(), dst_die.GetOffset());
4048           }
4049         } else {
4050           if (log)
4051             log->Printf("warning: couldn't find a match for 0x%8.8x",
4052                         dst_die.GetOffset());
4053 
4054           failures.Append(dst_die);
4055         }
4056       }
4057     }
4058   }
4059 
4060   const uint32_t src_size_artificial = src_name_to_die_artificial.GetSize();
4061   const uint32_t dst_size_artificial = dst_name_to_die_artificial.GetSize();
4062 
4063   if (src_size_artificial && dst_size_artificial) {
4064     dst_name_to_die_artificial.Sort();
4065 
4066     for (idx = 0; idx < src_size_artificial; ++idx) {
4067       ConstString src_name_artificial =
4068           src_name_to_die_artificial.GetCStringAtIndex(idx);
4069       src_die = src_name_to_die_artificial.GetValueAtIndexUnchecked(idx);
4070       dst_die =
4071           dst_name_to_die_artificial.Find(src_name_artificial, DWARFDIE());
4072 
4073       if (dst_die) {
4074         // Both classes have the artificial types, link them
4075         clang::DeclContext *src_decl_ctx =
4076             src_dwarf_ast_parser->m_die_to_decl_ctx[src_die.GetDIE()];
4077         if (src_decl_ctx) {
4078           if (log)
4079             log->Printf("uniquing decl context %p from 0x%8.8x for 0x%8.8x",
4080                         static_cast<void *>(src_decl_ctx), src_die.GetOffset(),
4081                         dst_die.GetOffset());
4082           dst_dwarf_ast_parser->LinkDeclContextToDIE(src_decl_ctx, dst_die);
4083         } else {
4084           if (log)
4085             log->Printf("warning: tried to unique decl context from 0x%8.8x "
4086                         "for 0x%8.8x, but none was found",
4087                         src_die.GetOffset(), dst_die.GetOffset());
4088         }
4089 
4090         Type *src_child_type =
4091             dst_die.GetDWARF()->GetDIEToType()[src_die.GetDIE()];
4092         if (src_child_type) {
4093           if (log)
4094             log->Printf(
4095                 "uniquing type %p (uid=0x%" PRIx64 ") from 0x%8.8x for 0x%8.8x",
4096                 static_cast<void *>(src_child_type), src_child_type->GetID(),
4097                 src_die.GetOffset(), dst_die.GetOffset());
4098           dst_die.GetDWARF()->GetDIEToType()[dst_die.GetDIE()] = src_child_type;
4099         } else {
4100           if (log)
4101             log->Printf("warning: tried to unique lldb_private::Type from "
4102                         "0x%8.8x for 0x%8.8x, but none was found",
4103                         src_die.GetOffset(), dst_die.GetOffset());
4104         }
4105       }
4106     }
4107   }
4108 
4109   if (dst_size_artificial) {
4110     for (idx = 0; idx < dst_size_artificial; ++idx) {
4111       ConstString dst_name_artificial =
4112           dst_name_to_die_artificial.GetCStringAtIndex(idx);
4113       dst_die = dst_name_to_die_artificial.GetValueAtIndexUnchecked(idx);
4114       if (log)
4115         log->Printf("warning: need to create artificial method for 0x%8.8x for "
4116                     "method '%s'",
4117                     dst_die.GetOffset(), dst_name_artificial.GetCString());
4118 
4119       failures.Append(dst_die);
4120     }
4121   }
4122 
4123   return (failures.Size() != 0);
4124 }
4125