1 //===-- ClangExpressionDeclMap.cpp -----------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "ClangExpressionDeclMap.h"
10 
11 #include "ClangASTSource.h"
12 #include "ClangModulesDeclVendor.h"
13 #include "ClangPersistentVariables.h"
14 
15 #include "lldb/Core/Address.h"
16 #include "lldb/Core/Module.h"
17 #include "lldb/Core/ModuleSpec.h"
18 #include "lldb/Core/ValueObjectConstResult.h"
19 #include "lldb/Core/ValueObjectVariable.h"
20 #include "lldb/Expression/Materializer.h"
21 #include "lldb/Symbol/ClangASTContext.h"
22 #include "lldb/Symbol/ClangUtil.h"
23 #include "lldb/Symbol/CompileUnit.h"
24 #include "lldb/Symbol/CompilerDecl.h"
25 #include "lldb/Symbol/CompilerDeclContext.h"
26 #include "lldb/Symbol/Function.h"
27 #include "lldb/Symbol/ObjectFile.h"
28 #include "lldb/Symbol/SymbolContext.h"
29 #include "lldb/Symbol/SymbolFile.h"
30 #include "lldb/Symbol/SymbolVendor.h"
31 #include "lldb/Symbol/Type.h"
32 #include "lldb/Symbol/TypeList.h"
33 #include "lldb/Symbol/Variable.h"
34 #include "lldb/Symbol/VariableList.h"
35 #include "lldb/Target/ExecutionContext.h"
36 #include "lldb/Target/Process.h"
37 #include "lldb/Target/RegisterContext.h"
38 #include "lldb/Target/StackFrame.h"
39 #include "lldb/Target/Target.h"
40 #include "lldb/Target/Thread.h"
41 #include "lldb/Utility/Endian.h"
42 #include "lldb/Utility/Log.h"
43 #include "lldb/Utility/RegisterValue.h"
44 #include "lldb/Utility/Status.h"
45 #include "lldb/lldb-private.h"
46 #include "clang/AST/ASTConsumer.h"
47 #include "clang/AST/ASTContext.h"
48 #include "clang/AST/ASTImporter.h"
49 #include "clang/AST/Decl.h"
50 #include "clang/AST/DeclarationName.h"
51 #include "clang/AST/RecursiveASTVisitor.h"
52 
53 #include "Plugins/Language/CPlusPlus/CPlusPlusLanguage.h"
54 #include "Plugins/LanguageRuntime/CPlusPlus/CPPLanguageRuntime.h"
55 #include "Plugins/LanguageRuntime/ObjC/ObjCLanguageRuntime.h"
56 
57 using namespace lldb;
58 using namespace lldb_private;
59 using namespace clang;
60 
61 namespace {
62 const char *g_lldb_local_vars_namespace_cstr = "$__lldb_local_vars";
63 } // anonymous namespace
64 
65 ClangExpressionDeclMap::ClangExpressionDeclMap(
66     bool keep_result_in_memory,
67     Materializer::PersistentVariableDelegate *result_delegate,
68     ExecutionContext &exe_ctx, ValueObject *ctx_obj)
69     : ClangASTSource(exe_ctx.GetTargetSP()), m_found_entities(),
70       m_struct_members(), m_keep_result_in_memory(keep_result_in_memory),
71       m_result_delegate(result_delegate), m_ctx_obj(ctx_obj), m_parser_vars(),
72       m_struct_vars() {
73   EnableStructVars();
74 }
75 
76 ClangExpressionDeclMap::~ClangExpressionDeclMap() {
77   // Note: The model is now that the parser's AST context and all associated
78   //   data does not vanish until the expression has been executed.  This means
79   //   that valuable lookup data (like namespaces) doesn't vanish, but
80 
81   DidParse();
82   DisableStructVars();
83 }
84 
85 bool ClangExpressionDeclMap::WillParse(ExecutionContext &exe_ctx,
86                                        Materializer *materializer) {
87   ClangASTMetrics::ClearLocalCounters();
88 
89   EnableParserVars();
90   m_parser_vars->m_exe_ctx = exe_ctx;
91 
92   Target *target = exe_ctx.GetTargetPtr();
93   if (exe_ctx.GetFramePtr())
94     m_parser_vars->m_sym_ctx =
95         exe_ctx.GetFramePtr()->GetSymbolContext(lldb::eSymbolContextEverything);
96   else if (exe_ctx.GetThreadPtr() &&
97            exe_ctx.GetThreadPtr()->GetStackFrameAtIndex(0))
98     m_parser_vars->m_sym_ctx =
99         exe_ctx.GetThreadPtr()->GetStackFrameAtIndex(0)->GetSymbolContext(
100             lldb::eSymbolContextEverything);
101   else if (exe_ctx.GetProcessPtr()) {
102     m_parser_vars->m_sym_ctx.Clear(true);
103     m_parser_vars->m_sym_ctx.target_sp = exe_ctx.GetTargetSP();
104   } else if (target) {
105     m_parser_vars->m_sym_ctx.Clear(true);
106     m_parser_vars->m_sym_ctx.target_sp = exe_ctx.GetTargetSP();
107   }
108 
109   if (target) {
110     m_parser_vars->m_persistent_vars = llvm::cast<ClangPersistentVariables>(
111         target->GetPersistentExpressionStateForLanguage(eLanguageTypeC));
112 
113     if (!target->GetScratchClangASTContext())
114       return false;
115   }
116 
117   m_parser_vars->m_target_info = GetTargetInfo();
118   m_parser_vars->m_materializer = materializer;
119 
120   return true;
121 }
122 
123 void ClangExpressionDeclMap::InstallCodeGenerator(
124     clang::ASTConsumer *code_gen) {
125   assert(m_parser_vars);
126   m_parser_vars->m_code_gen = code_gen;
127 }
128 
129 void ClangExpressionDeclMap::DidParse() {
130   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
131 
132   if (log)
133     ClangASTMetrics::DumpCounters(log);
134 
135   if (m_parser_vars) {
136     for (size_t entity_index = 0, num_entities = m_found_entities.GetSize();
137          entity_index < num_entities; ++entity_index) {
138       ExpressionVariableSP var_sp(
139           m_found_entities.GetVariableAtIndex(entity_index));
140       if (var_sp)
141         llvm::cast<ClangExpressionVariable>(var_sp.get())
142             ->DisableParserVars(GetParserID());
143     }
144 
145     for (size_t pvar_index = 0,
146                 num_pvars = m_parser_vars->m_persistent_vars->GetSize();
147          pvar_index < num_pvars; ++pvar_index) {
148       ExpressionVariableSP pvar_sp(
149           m_parser_vars->m_persistent_vars->GetVariableAtIndex(pvar_index));
150       if (ClangExpressionVariable *clang_var =
151               llvm::dyn_cast<ClangExpressionVariable>(pvar_sp.get()))
152         clang_var->DisableParserVars(GetParserID());
153     }
154 
155     DisableParserVars();
156   }
157 }
158 
159 // Interface for IRForTarget
160 
161 ClangExpressionDeclMap::TargetInfo ClangExpressionDeclMap::GetTargetInfo() {
162   assert(m_parser_vars.get());
163 
164   TargetInfo ret;
165 
166   ExecutionContext &exe_ctx = m_parser_vars->m_exe_ctx;
167 
168   Process *process = exe_ctx.GetProcessPtr();
169   if (process) {
170     ret.byte_order = process->GetByteOrder();
171     ret.address_byte_size = process->GetAddressByteSize();
172   } else {
173     Target *target = exe_ctx.GetTargetPtr();
174     if (target) {
175       ret.byte_order = target->GetArchitecture().GetByteOrder();
176       ret.address_byte_size = target->GetArchitecture().GetAddressByteSize();
177     }
178   }
179 
180   return ret;
181 }
182 
183 static clang::QualType ExportAllDeclaredTypes(
184     clang::ExternalASTMerger &parent_merger, clang::ExternalASTMerger &merger,
185     clang::ASTContext &source, clang::FileManager &source_file_manager,
186     const clang::ExternalASTMerger::OriginMap &source_origin_map,
187     clang::FileID file, clang::QualType root) {
188   // Mark the source as temporary to make sure all declarations from the
189   // AST are exported. Also add the parent_merger as the merger into the
190   // source AST so that the merger can track back any declarations from
191   // the persistent ASTs we used as sources.
192   clang::ExternalASTMerger::ImporterSource importer_source(
193       source, source_file_manager, source_origin_map, /*Temporary*/ true,
194       &parent_merger);
195   merger.AddSources(importer_source);
196   clang::ASTImporter &exporter = merger.ImporterForOrigin(source);
197   llvm::Expected<clang::QualType> ret_or_error = exporter.Import(root);
198   merger.RemoveSources(importer_source);
199   if (ret_or_error) {
200     return *ret_or_error;
201   } else {
202     Log *log = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS);
203     LLDB_LOG_ERROR(log, ret_or_error.takeError(), "Couldn't import type: {0}");
204     return clang::QualType();
205   }
206 }
207 
208 TypeFromUser ClangExpressionDeclMap::DeportType(ClangASTContext &target,
209                                                 ClangASTContext &source,
210                                                 TypeFromParser parser_type) {
211   assert(&target == m_target->GetScratchClangASTContext());
212   assert((TypeSystem *)&source == parser_type.GetTypeSystem());
213   assert(source.getASTContext() == m_ast_context);
214 
215   if (m_ast_importer_sp) {
216     return TypeFromUser(m_ast_importer_sp->DeportType(
217                             target.getASTContext(), source.getASTContext(),
218                             parser_type.GetOpaqueQualType()),
219                         &target);
220   } else if (m_merger_up) {
221     clang::FileID source_file =
222         source.getASTContext()->getSourceManager().getFileID(
223             source.getASTContext()->getTranslationUnitDecl()->getLocation());
224     auto scratch_ast_context = static_cast<ClangASTContextForExpressions *>(
225         m_target->GetScratchClangASTContext());
226     clang::QualType exported_type = ExportAllDeclaredTypes(
227         *m_merger_up.get(), scratch_ast_context->GetMergerUnchecked(),
228         *source.getASTContext(), *source.getFileManager(),
229         m_merger_up->GetOrigins(), source_file,
230         clang::QualType::getFromOpaquePtr(parser_type.GetOpaqueQualType()));
231     return TypeFromUser(exported_type.getAsOpaquePtr(), &target);
232   } else {
233     lldbassert(0 && "No mechanism for deporting a type!");
234     return TypeFromUser();
235   }
236 }
237 
238 bool ClangExpressionDeclMap::AddPersistentVariable(const NamedDecl *decl,
239                                                    ConstString name,
240                                                    TypeFromParser parser_type,
241                                                    bool is_result,
242                                                    bool is_lvalue) {
243   assert(m_parser_vars.get());
244 
245   ClangASTContext *ast =
246       llvm::dyn_cast_or_null<ClangASTContext>(parser_type.GetTypeSystem());
247   if (ast == nullptr)
248     return false;
249 
250   if (m_parser_vars->m_materializer && is_result) {
251     Status err;
252 
253     ExecutionContext &exe_ctx = m_parser_vars->m_exe_ctx;
254     Target *target = exe_ctx.GetTargetPtr();
255     if (target == nullptr)
256       return false;
257 
258     TypeFromUser user_type =
259         DeportType(*target->GetScratchClangASTContext(), *ast, parser_type);
260 
261     uint32_t offset = m_parser_vars->m_materializer->AddResultVariable(
262         user_type, is_lvalue, m_keep_result_in_memory, m_result_delegate, err);
263 
264     ClangExpressionVariable *var = new ClangExpressionVariable(
265         exe_ctx.GetBestExecutionContextScope(), name, user_type,
266         m_parser_vars->m_target_info.byte_order,
267         m_parser_vars->m_target_info.address_byte_size);
268 
269     m_found_entities.AddNewlyConstructedVariable(var);
270 
271     var->EnableParserVars(GetParserID());
272 
273     ClangExpressionVariable::ParserVars *parser_vars =
274         var->GetParserVars(GetParserID());
275 
276     parser_vars->m_named_decl = decl;
277     parser_vars->m_parser_type = parser_type;
278 
279     var->EnableJITVars(GetParserID());
280 
281     ClangExpressionVariable::JITVars *jit_vars = var->GetJITVars(GetParserID());
282 
283     jit_vars->m_offset = offset;
284 
285     return true;
286   }
287 
288   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
289   ExecutionContext &exe_ctx = m_parser_vars->m_exe_ctx;
290   Target *target = exe_ctx.GetTargetPtr();
291   if (target == nullptr)
292     return false;
293 
294   ClangASTContext *context(target->GetScratchClangASTContext());
295 
296   TypeFromUser user_type = DeportType(*context, *ast, parser_type);
297 
298   if (!user_type.GetOpaqueQualType()) {
299     LLDB_LOGF(log, "Persistent variable's type wasn't copied successfully");
300     return false;
301   }
302 
303   if (!m_parser_vars->m_target_info.IsValid())
304     return false;
305 
306   ClangExpressionVariable *var = llvm::cast<ClangExpressionVariable>(
307       m_parser_vars->m_persistent_vars
308           ->CreatePersistentVariable(
309               exe_ctx.GetBestExecutionContextScope(), name, user_type,
310               m_parser_vars->m_target_info.byte_order,
311               m_parser_vars->m_target_info.address_byte_size)
312           .get());
313 
314   if (!var)
315     return false;
316 
317   var->m_frozen_sp->SetHasCompleteType();
318 
319   if (is_result)
320     var->m_flags |= ClangExpressionVariable::EVNeedsFreezeDry;
321   else
322     var->m_flags |=
323         ClangExpressionVariable::EVKeepInTarget; // explicitly-declared
324                                                  // persistent variables should
325                                                  // persist
326 
327   if (is_lvalue) {
328     var->m_flags |= ClangExpressionVariable::EVIsProgramReference;
329   } else {
330     var->m_flags |= ClangExpressionVariable::EVIsLLDBAllocated;
331     var->m_flags |= ClangExpressionVariable::EVNeedsAllocation;
332   }
333 
334   if (m_keep_result_in_memory) {
335     var->m_flags |= ClangExpressionVariable::EVKeepInTarget;
336   }
337 
338   LLDB_LOGF(log, "Created persistent variable with flags 0x%hx", var->m_flags);
339 
340   var->EnableParserVars(GetParserID());
341 
342   ClangExpressionVariable::ParserVars *parser_vars =
343       var->GetParserVars(GetParserID());
344 
345   parser_vars->m_named_decl = decl;
346   parser_vars->m_parser_type = parser_type;
347 
348   return true;
349 }
350 
351 bool ClangExpressionDeclMap::AddValueToStruct(const NamedDecl *decl,
352                                               ConstString name,
353                                               llvm::Value *value, size_t size,
354                                               lldb::offset_t alignment) {
355   assert(m_struct_vars.get());
356   assert(m_parser_vars.get());
357 
358   bool is_persistent_variable = false;
359 
360   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
361 
362   m_struct_vars->m_struct_laid_out = false;
363 
364   if (ClangExpressionVariable::FindVariableInList(m_struct_members, decl,
365                                                   GetParserID()))
366     return true;
367 
368   ClangExpressionVariable *var(ClangExpressionVariable::FindVariableInList(
369       m_found_entities, decl, GetParserID()));
370 
371   if (!var) {
372     var = ClangExpressionVariable::FindVariableInList(
373         *m_parser_vars->m_persistent_vars, decl, GetParserID());
374     is_persistent_variable = true;
375   }
376 
377   if (!var)
378     return false;
379 
380   LLDB_LOGF(log, "Adding value for (NamedDecl*)%p [%s - %s] to the structure",
381             static_cast<const void *>(decl), name.GetCString(),
382             var->GetName().GetCString());
383 
384   // We know entity->m_parser_vars is valid because we used a parser variable
385   // to find it
386 
387   ClangExpressionVariable::ParserVars *parser_vars =
388       llvm::cast<ClangExpressionVariable>(var)->GetParserVars(GetParserID());
389 
390   parser_vars->m_llvm_value = value;
391 
392   if (ClangExpressionVariable::JITVars *jit_vars =
393           llvm::cast<ClangExpressionVariable>(var)->GetJITVars(GetParserID())) {
394     // We already laid this out; do not touch
395 
396     LLDB_LOGF(log, "Already placed at 0x%llx",
397               (unsigned long long)jit_vars->m_offset);
398   }
399 
400   llvm::cast<ClangExpressionVariable>(var)->EnableJITVars(GetParserID());
401 
402   ClangExpressionVariable::JITVars *jit_vars =
403       llvm::cast<ClangExpressionVariable>(var)->GetJITVars(GetParserID());
404 
405   jit_vars->m_alignment = alignment;
406   jit_vars->m_size = size;
407 
408   m_struct_members.AddVariable(var->shared_from_this());
409 
410   if (m_parser_vars->m_materializer) {
411     uint32_t offset = 0;
412 
413     Status err;
414 
415     if (is_persistent_variable) {
416       ExpressionVariableSP var_sp(var->shared_from_this());
417       offset = m_parser_vars->m_materializer->AddPersistentVariable(
418           var_sp, nullptr, err);
419     } else {
420       if (const lldb_private::Symbol *sym = parser_vars->m_lldb_sym)
421         offset = m_parser_vars->m_materializer->AddSymbol(*sym, err);
422       else if (const RegisterInfo *reg_info = var->GetRegisterInfo())
423         offset = m_parser_vars->m_materializer->AddRegister(*reg_info, err);
424       else if (parser_vars->m_lldb_var)
425         offset = m_parser_vars->m_materializer->AddVariable(
426             parser_vars->m_lldb_var, err);
427     }
428 
429     if (!err.Success())
430       return false;
431 
432     LLDB_LOGF(log, "Placed at 0x%llx", (unsigned long long)offset);
433 
434     jit_vars->m_offset =
435         offset; // TODO DoStructLayout() should not change this.
436   }
437 
438   return true;
439 }
440 
441 bool ClangExpressionDeclMap::DoStructLayout() {
442   assert(m_struct_vars.get());
443 
444   if (m_struct_vars->m_struct_laid_out)
445     return true;
446 
447   if (!m_parser_vars->m_materializer)
448     return false;
449 
450   m_struct_vars->m_struct_alignment =
451       m_parser_vars->m_materializer->GetStructAlignment();
452   m_struct_vars->m_struct_size =
453       m_parser_vars->m_materializer->GetStructByteSize();
454   m_struct_vars->m_struct_laid_out = true;
455   return true;
456 }
457 
458 bool ClangExpressionDeclMap::GetStructInfo(uint32_t &num_elements, size_t &size,
459                                            lldb::offset_t &alignment) {
460   assert(m_struct_vars.get());
461 
462   if (!m_struct_vars->m_struct_laid_out)
463     return false;
464 
465   num_elements = m_struct_members.GetSize();
466   size = m_struct_vars->m_struct_size;
467   alignment = m_struct_vars->m_struct_alignment;
468 
469   return true;
470 }
471 
472 bool ClangExpressionDeclMap::GetStructElement(const NamedDecl *&decl,
473                                               llvm::Value *&value,
474                                               lldb::offset_t &offset,
475                                               ConstString &name,
476                                               uint32_t index) {
477   assert(m_struct_vars.get());
478 
479   if (!m_struct_vars->m_struct_laid_out)
480     return false;
481 
482   if (index >= m_struct_members.GetSize())
483     return false;
484 
485   ExpressionVariableSP member_sp(m_struct_members.GetVariableAtIndex(index));
486 
487   if (!member_sp)
488     return false;
489 
490   ClangExpressionVariable::ParserVars *parser_vars =
491       llvm::cast<ClangExpressionVariable>(member_sp.get())
492           ->GetParserVars(GetParserID());
493   ClangExpressionVariable::JITVars *jit_vars =
494       llvm::cast<ClangExpressionVariable>(member_sp.get())
495           ->GetJITVars(GetParserID());
496 
497   if (!parser_vars || !jit_vars || !member_sp->GetValueObject())
498     return false;
499 
500   decl = parser_vars->m_named_decl;
501   value = parser_vars->m_llvm_value;
502   offset = jit_vars->m_offset;
503   name = member_sp->GetName();
504 
505   return true;
506 }
507 
508 bool ClangExpressionDeclMap::GetFunctionInfo(const NamedDecl *decl,
509                                              uint64_t &ptr) {
510   ClangExpressionVariable *entity(ClangExpressionVariable::FindVariableInList(
511       m_found_entities, decl, GetParserID()));
512 
513   if (!entity)
514     return false;
515 
516   // We know m_parser_vars is valid since we searched for the variable by its
517   // NamedDecl
518 
519   ClangExpressionVariable::ParserVars *parser_vars =
520       entity->GetParserVars(GetParserID());
521 
522   ptr = parser_vars->m_lldb_value.GetScalar().ULongLong();
523 
524   return true;
525 }
526 
527 addr_t ClangExpressionDeclMap::GetSymbolAddress(Target &target,
528                                                 Process *process,
529                                                 ConstString name,
530                                                 lldb::SymbolType symbol_type,
531                                                 lldb_private::Module *module) {
532   SymbolContextList sc_list;
533 
534   if (module)
535     module->FindSymbolsWithNameAndType(name, symbol_type, sc_list);
536   else
537     target.GetImages().FindSymbolsWithNameAndType(name, symbol_type, sc_list);
538 
539   const uint32_t num_matches = sc_list.GetSize();
540   addr_t symbol_load_addr = LLDB_INVALID_ADDRESS;
541 
542   for (uint32_t i = 0;
543        i < num_matches &&
544        (symbol_load_addr == 0 || symbol_load_addr == LLDB_INVALID_ADDRESS);
545        i++) {
546     SymbolContext sym_ctx;
547     sc_list.GetContextAtIndex(i, sym_ctx);
548 
549     const Address sym_address = sym_ctx.symbol->GetAddress();
550 
551     if (!sym_address.IsValid())
552       continue;
553 
554     switch (sym_ctx.symbol->GetType()) {
555     case eSymbolTypeCode:
556     case eSymbolTypeTrampoline:
557       symbol_load_addr = sym_address.GetCallableLoadAddress(&target);
558       break;
559 
560     case eSymbolTypeResolver:
561       symbol_load_addr = sym_address.GetCallableLoadAddress(&target, true);
562       break;
563 
564     case eSymbolTypeReExported: {
565       ConstString reexport_name = sym_ctx.symbol->GetReExportedSymbolName();
566       if (reexport_name) {
567         ModuleSP reexport_module_sp;
568         ModuleSpec reexport_module_spec;
569         reexport_module_spec.GetPlatformFileSpec() =
570             sym_ctx.symbol->GetReExportedSymbolSharedLibrary();
571         if (reexport_module_spec.GetPlatformFileSpec()) {
572           reexport_module_sp =
573               target.GetImages().FindFirstModule(reexport_module_spec);
574           if (!reexport_module_sp) {
575             reexport_module_spec.GetPlatformFileSpec().GetDirectory().Clear();
576             reexport_module_sp =
577                 target.GetImages().FindFirstModule(reexport_module_spec);
578           }
579         }
580         symbol_load_addr = GetSymbolAddress(
581             target, process, sym_ctx.symbol->GetReExportedSymbolName(),
582             symbol_type, reexport_module_sp.get());
583       }
584     } break;
585 
586     case eSymbolTypeData:
587     case eSymbolTypeRuntime:
588     case eSymbolTypeVariable:
589     case eSymbolTypeLocal:
590     case eSymbolTypeParam:
591     case eSymbolTypeInvalid:
592     case eSymbolTypeAbsolute:
593     case eSymbolTypeException:
594     case eSymbolTypeSourceFile:
595     case eSymbolTypeHeaderFile:
596     case eSymbolTypeObjectFile:
597     case eSymbolTypeCommonBlock:
598     case eSymbolTypeBlock:
599     case eSymbolTypeVariableType:
600     case eSymbolTypeLineEntry:
601     case eSymbolTypeLineHeader:
602     case eSymbolTypeScopeBegin:
603     case eSymbolTypeScopeEnd:
604     case eSymbolTypeAdditional:
605     case eSymbolTypeCompiler:
606     case eSymbolTypeInstrumentation:
607     case eSymbolTypeUndefined:
608     case eSymbolTypeObjCClass:
609     case eSymbolTypeObjCMetaClass:
610     case eSymbolTypeObjCIVar:
611       symbol_load_addr = sym_address.GetLoadAddress(&target);
612       break;
613     }
614   }
615 
616   if (symbol_load_addr == LLDB_INVALID_ADDRESS && process) {
617     ObjCLanguageRuntime *runtime = ObjCLanguageRuntime::Get(*process);
618 
619     if (runtime) {
620       symbol_load_addr = runtime->LookupRuntimeSymbol(name);
621     }
622   }
623 
624   return symbol_load_addr;
625 }
626 
627 addr_t ClangExpressionDeclMap::GetSymbolAddress(ConstString name,
628                                                 lldb::SymbolType symbol_type) {
629   assert(m_parser_vars.get());
630 
631   if (!m_parser_vars->m_exe_ctx.GetTargetPtr())
632     return false;
633 
634   return GetSymbolAddress(m_parser_vars->m_exe_ctx.GetTargetRef(),
635                           m_parser_vars->m_exe_ctx.GetProcessPtr(), name,
636                           symbol_type);
637 }
638 
639 lldb::VariableSP ClangExpressionDeclMap::FindGlobalVariable(
640     Target &target, ModuleSP &module, ConstString name,
641     CompilerDeclContext *namespace_decl, TypeFromUser *type) {
642   VariableList vars;
643 
644   if (module && namespace_decl)
645     module->FindGlobalVariables(name, namespace_decl, -1, vars);
646   else
647     target.GetImages().FindGlobalVariables(name, -1, vars);
648 
649   if (vars.GetSize()) {
650     if (type) {
651       for (VariableSP var_sp : vars) {
652         if (ClangASTContext::AreTypesSame(
653                 *type, var_sp->GetType()->GetFullCompilerType()))
654           return var_sp;
655       }
656     } else {
657       return vars.GetVariableAtIndex(0);
658     }
659   }
660 
661   return VariableSP();
662 }
663 
664 ClangASTContext *ClangExpressionDeclMap::GetClangASTContext() {
665   StackFrame *frame = m_parser_vars->m_exe_ctx.GetFramePtr();
666   if (frame == nullptr)
667     return nullptr;
668 
669   SymbolContext sym_ctx = frame->GetSymbolContext(lldb::eSymbolContextFunction |
670                                                   lldb::eSymbolContextBlock);
671   if (sym_ctx.block == nullptr)
672     return nullptr;
673 
674   CompilerDeclContext frame_decl_context = sym_ctx.block->GetDeclContext();
675   if (!frame_decl_context)
676     return nullptr;
677 
678   return llvm::dyn_cast_or_null<ClangASTContext>(
679       frame_decl_context.GetTypeSystem());
680 }
681 
682 // Interface for ClangASTSource
683 
684 void ClangExpressionDeclMap::FindExternalVisibleDecls(
685     NameSearchContext &context) {
686   assert(m_ast_context);
687 
688   ClangASTMetrics::RegisterVisibleQuery();
689 
690   const ConstString name(context.m_decl_name.getAsString().c_str());
691 
692   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
693 
694   if (GetImportInProgress()) {
695     if (log && log->GetVerbose())
696       LLDB_LOGF(log, "Ignoring a query during an import");
697     return;
698   }
699 
700   static unsigned int invocation_id = 0;
701   unsigned int current_id = invocation_id++;
702 
703   if (log) {
704     if (!context.m_decl_context)
705       LLDB_LOGF(log,
706                 "ClangExpressionDeclMap::FindExternalVisibleDecls[%u] for "
707                 "'%s' in a NULL DeclContext",
708                 current_id, name.GetCString());
709     else if (const NamedDecl *context_named_decl =
710                  dyn_cast<NamedDecl>(context.m_decl_context))
711       LLDB_LOGF(log,
712                 "ClangExpressionDeclMap::FindExternalVisibleDecls[%u] for "
713                 "'%s' in '%s'",
714                 current_id, name.GetCString(),
715                 context_named_decl->getNameAsString().c_str());
716     else
717       LLDB_LOGF(log,
718                 "ClangExpressionDeclMap::FindExternalVisibleDecls[%u] for "
719                 "'%s' in a '%s'",
720                 current_id, name.GetCString(),
721                 context.m_decl_context->getDeclKindName());
722   }
723 
724   if (const NamespaceDecl *namespace_context =
725           dyn_cast<NamespaceDecl>(context.m_decl_context)) {
726     if (namespace_context->getName().str() ==
727         std::string(g_lldb_local_vars_namespace_cstr)) {
728       CompilerDeclContext compiler_decl_ctx(
729           GetClangASTContext(), const_cast<void *>(static_cast<const void *>(
730                                     context.m_decl_context)));
731       FindExternalVisibleDecls(context, lldb::ModuleSP(), compiler_decl_ctx,
732                                current_id);
733       return;
734     }
735 
736     ClangASTImporter::NamespaceMapSP namespace_map =
737         m_ast_importer_sp
738             ? m_ast_importer_sp->GetNamespaceMap(namespace_context)
739             : ClangASTImporter::NamespaceMapSP();
740 
741     if (!namespace_map)
742       return;
743 
744     if (log && log->GetVerbose())
745       log->Printf("  CEDM::FEVD[%u] Inspecting (NamespaceMap*)%p (%d entries)",
746                   current_id, static_cast<void *>(namespace_map.get()),
747                   (int)namespace_map->size());
748 
749     for (ClangASTImporter::NamespaceMap::iterator i = namespace_map->begin(),
750                                                   e = namespace_map->end();
751          i != e; ++i) {
752       if (log)
753         log->Printf("  CEDM::FEVD[%u] Searching namespace %s in module %s",
754                     current_id, i->second.GetName().AsCString(),
755                     i->first->GetFileSpec().GetFilename().GetCString());
756 
757       FindExternalVisibleDecls(context, i->first, i->second, current_id);
758     }
759   } else if (isa<TranslationUnitDecl>(context.m_decl_context)) {
760     CompilerDeclContext namespace_decl;
761 
762     if (log)
763       log->Printf("  CEDM::FEVD[%u] Searching the root namespace", current_id);
764 
765     FindExternalVisibleDecls(context, lldb::ModuleSP(), namespace_decl,
766                              current_id);
767   }
768 
769   ClangASTSource::FindExternalVisibleDecls(context);
770 }
771 
772 void ClangExpressionDeclMap::MaybeRegisterFunctionBody(
773     FunctionDecl *copied_function_decl) {
774   if (copied_function_decl->getBody() && m_parser_vars->m_code_gen) {
775     clang::DeclGroupRef decl_group_ref(copied_function_decl);
776     m_parser_vars->m_code_gen->HandleTopLevelDecl(decl_group_ref);
777   }
778 }
779 
780 void ClangExpressionDeclMap::SearchPersistenDecls(NameSearchContext &context,
781                                                   const ConstString name,
782                                                   unsigned int current_id) {
783   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
784   Target *target = m_parser_vars->m_exe_ctx.GetTargetPtr();
785   if (!target)
786     return;
787 
788   ClangASTContext *scratch_clang_ast_context =
789       target->GetScratchClangASTContext();
790 
791   if (!scratch_clang_ast_context)
792     return;
793 
794   ASTContext *scratch_ast_context = scratch_clang_ast_context->getASTContext();
795 
796   if (!scratch_ast_context)
797     return;
798 
799   NamedDecl *persistent_decl =
800       m_parser_vars->m_persistent_vars->GetPersistentDecl(name);
801 
802   if (!persistent_decl)
803     return;
804 
805   Decl *parser_persistent_decl = CopyDecl(persistent_decl);
806 
807   if (!parser_persistent_decl)
808     return;
809 
810   NamedDecl *parser_named_decl = dyn_cast<NamedDecl>(parser_persistent_decl);
811 
812   if (!parser_named_decl)
813     return;
814 
815   if (clang::FunctionDecl *parser_function_decl =
816           llvm::dyn_cast<clang::FunctionDecl>(parser_named_decl)) {
817     MaybeRegisterFunctionBody(parser_function_decl);
818   }
819 
820   LLDB_LOGF(log, "  CEDM::FEVD[%u] Found persistent decl %s", current_id,
821             name.GetCString());
822 
823   context.AddNamedDecl(parser_named_decl);
824 }
825 
826 void ClangExpressionDeclMap::LookUpLldbClass(NameSearchContext &context,
827                                              unsigned int current_id) {
828   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
829 
830   StackFrame *frame = m_parser_vars->m_exe_ctx.GetFramePtr();
831   SymbolContext sym_ctx;
832   if (frame != nullptr)
833     sym_ctx = frame->GetSymbolContext(lldb::eSymbolContextFunction |
834                                       lldb::eSymbolContextBlock);
835 
836   if (m_ctx_obj) {
837     Status status;
838     lldb::ValueObjectSP ctx_obj_ptr = m_ctx_obj->AddressOf(status);
839     if (!ctx_obj_ptr || status.Fail())
840       return;
841 
842     AddThisType(context, TypeFromUser(m_ctx_obj->GetCompilerType()),
843                 current_id);
844 
845     m_struct_vars->m_object_pointer_type =
846         TypeFromUser(ctx_obj_ptr->GetCompilerType());
847 
848     return;
849   }
850 
851   // Clang is looking for the type of "this"
852 
853   if (frame == nullptr)
854     return;
855 
856   // Find the block that defines the function represented by "sym_ctx"
857   Block *function_block = sym_ctx.GetFunctionBlock();
858 
859   if (!function_block)
860     return;
861 
862   CompilerDeclContext function_decl_ctx = function_block->GetDeclContext();
863 
864   if (!function_decl_ctx)
865     return;
866 
867   clang::CXXMethodDecl *method_decl =
868       ClangASTContext::DeclContextGetAsCXXMethodDecl(function_decl_ctx);
869 
870   if (method_decl) {
871     clang::CXXRecordDecl *class_decl = method_decl->getParent();
872 
873     QualType class_qual_type(class_decl->getTypeForDecl(), 0);
874 
875     TypeFromUser class_user_type(
876         class_qual_type.getAsOpaquePtr(),
877         ClangASTContext::GetASTContext(&class_decl->getASTContext()));
878 
879     LLDB_LOG(log, "  CEDM::FEVD[{0}] Adding type for $__lldb_class: {1}",
880              current_id, class_qual_type.getAsString());
881 
882     AddThisType(context, class_user_type, current_id);
883 
884     if (method_decl->isInstance()) {
885       // self is a pointer to the object
886 
887       QualType class_pointer_type =
888           method_decl->getASTContext().getPointerType(class_qual_type);
889 
890       TypeFromUser self_user_type(
891           class_pointer_type.getAsOpaquePtr(),
892           ClangASTContext::GetASTContext(&method_decl->getASTContext()));
893 
894       m_struct_vars->m_object_pointer_type = self_user_type;
895     }
896     return;
897   }
898 
899   // This branch will get hit if we are executing code in the context of
900   // a function that claims to have an object pointer (through
901   // DW_AT_object_pointer?) but is not formally a method of the class.
902   // In that case, just look up the "this" variable in the current scope
903   // and use its type.
904   // FIXME: This code is formally correct, but clang doesn't currently
905   // emit DW_AT_object_pointer
906   // for C++ so it hasn't actually been tested.
907 
908   VariableList *vars = frame->GetVariableList(false);
909 
910   lldb::VariableSP this_var = vars->FindVariable(ConstString("this"));
911 
912   if (this_var && this_var->IsInScope(frame) &&
913       this_var->LocationIsValidForFrame(frame)) {
914     Type *this_type = this_var->GetType();
915 
916     if (!this_type)
917       return;
918 
919     TypeFromUser pointee_type =
920         this_type->GetForwardCompilerType().GetPointeeType();
921 
922     LLDB_LOG(log, "  FEVD[{0}] Adding type for $__lldb_class: {1}", current_id,
923              ClangUtil::GetQualType(pointee_type).getAsString());
924 
925     AddThisType(context, pointee_type, current_id);
926     TypeFromUser this_user_type(this_type->GetFullCompilerType());
927     m_struct_vars->m_object_pointer_type = this_user_type;
928   }
929 }
930 
931 void ClangExpressionDeclMap::LookUpLldbObjCClass(NameSearchContext &context,
932                                                  unsigned int current_id) {
933   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
934 
935   StackFrame *frame = m_parser_vars->m_exe_ctx.GetFramePtr();
936 
937   if (m_ctx_obj) {
938     Status status;
939     lldb::ValueObjectSP ctx_obj_ptr = m_ctx_obj->AddressOf(status);
940     if (!ctx_obj_ptr || status.Fail())
941       return;
942 
943     AddOneType(context, TypeFromUser(m_ctx_obj->GetCompilerType()), current_id);
944 
945     m_struct_vars->m_object_pointer_type =
946         TypeFromUser(ctx_obj_ptr->GetCompilerType());
947 
948     return;
949   }
950 
951   // Clang is looking for the type of "*self"
952 
953   if (!frame)
954     return;
955 
956   SymbolContext sym_ctx = frame->GetSymbolContext(lldb::eSymbolContextFunction |
957                                                   lldb::eSymbolContextBlock);
958 
959   // Find the block that defines the function represented by "sym_ctx"
960   Block *function_block = sym_ctx.GetFunctionBlock();
961 
962   if (!function_block)
963     return;
964 
965   CompilerDeclContext function_decl_ctx = function_block->GetDeclContext();
966 
967   if (!function_decl_ctx)
968     return;
969 
970   clang::ObjCMethodDecl *method_decl =
971       ClangASTContext::DeclContextGetAsObjCMethodDecl(function_decl_ctx);
972 
973   if (method_decl) {
974     ObjCInterfaceDecl *self_interface = method_decl->getClassInterface();
975 
976     if (!self_interface)
977       return;
978 
979     const clang::Type *interface_type = self_interface->getTypeForDecl();
980 
981     if (!interface_type)
982       return; // This is unlikely, but we have seen crashes where this
983               // occurred
984 
985     TypeFromUser class_user_type(
986         QualType(interface_type, 0).getAsOpaquePtr(),
987         ClangASTContext::GetASTContext(&method_decl->getASTContext()));
988 
989     LLDB_LOG(log, "  FEVD[{0}] Adding type for $__lldb_objc_class: {1}",
990              current_id, ClangUtil::ToString(interface_type));
991 
992     AddOneType(context, class_user_type, current_id);
993 
994     if (method_decl->isInstanceMethod()) {
995       // self is a pointer to the object
996 
997       QualType class_pointer_type =
998           method_decl->getASTContext().getObjCObjectPointerType(
999               QualType(interface_type, 0));
1000 
1001       TypeFromUser self_user_type(
1002           class_pointer_type.getAsOpaquePtr(),
1003           ClangASTContext::GetASTContext(&method_decl->getASTContext()));
1004 
1005       m_struct_vars->m_object_pointer_type = self_user_type;
1006     } else {
1007       // self is a Class pointer
1008       QualType class_type = method_decl->getASTContext().getObjCClassType();
1009 
1010       TypeFromUser self_user_type(
1011           class_type.getAsOpaquePtr(),
1012           ClangASTContext::GetASTContext(&method_decl->getASTContext()));
1013 
1014       m_struct_vars->m_object_pointer_type = self_user_type;
1015     }
1016 
1017     return;
1018   }
1019   // This branch will get hit if we are executing code in the context of
1020   // a function that claims to have an object pointer (through
1021   // DW_AT_object_pointer?) but is not formally a method of the class.
1022   // In that case, just look up the "self" variable in the current scope
1023   // and use its type.
1024 
1025   VariableList *vars = frame->GetVariableList(false);
1026 
1027   lldb::VariableSP self_var = vars->FindVariable(ConstString("self"));
1028 
1029   if (!self_var)
1030     return;
1031   if (!self_var->IsInScope(frame))
1032     return;
1033   if (!self_var->LocationIsValidForFrame(frame))
1034     return;
1035 
1036   Type *self_type = self_var->GetType();
1037 
1038   if (!self_type)
1039     return;
1040 
1041   CompilerType self_clang_type = self_type->GetFullCompilerType();
1042 
1043   if (ClangASTContext::IsObjCClassType(self_clang_type)) {
1044     return;
1045   }
1046   if (!ClangASTContext::IsObjCObjectPointerType(self_clang_type))
1047     return;
1048   self_clang_type = self_clang_type.GetPointeeType();
1049 
1050   if (!self_clang_type)
1051     return;
1052 
1053   LLDB_LOG(log, "  FEVD[{0}] Adding type for $__lldb_objc_class: {1}",
1054            current_id, ClangUtil::ToString(self_type->GetFullCompilerType()));
1055 
1056   TypeFromUser class_user_type(self_clang_type);
1057 
1058   AddOneType(context, class_user_type, current_id);
1059 
1060   TypeFromUser self_user_type(self_type->GetFullCompilerType());
1061 
1062   m_struct_vars->m_object_pointer_type = self_user_type;
1063 }
1064 
1065 void ClangExpressionDeclMap::LookupLocalVarNamespace(
1066     SymbolContext &sym_ctx, NameSearchContext &name_context) {
1067   if (sym_ctx.block == nullptr)
1068     return;
1069 
1070   CompilerDeclContext frame_decl_context = sym_ctx.block->GetDeclContext();
1071   if (!frame_decl_context)
1072     return;
1073 
1074   ClangASTContext *frame_ast = llvm::dyn_cast_or_null<ClangASTContext>(
1075       frame_decl_context.GetTypeSystem());
1076   if (!frame_ast)
1077     return;
1078 
1079   clang::NamespaceDecl *namespace_decl =
1080       m_clang_ast_context->GetUniqueNamespaceDeclaration(
1081           g_lldb_local_vars_namespace_cstr, nullptr);
1082   if (!namespace_decl)
1083     return;
1084 
1085   name_context.AddNamedDecl(namespace_decl);
1086   clang::DeclContext *ctxt = clang::Decl::castToDeclContext(namespace_decl);
1087   ctxt->setHasExternalVisibleStorage(true);
1088   name_context.m_found.local_vars_nsp = true;
1089 }
1090 
1091 void ClangExpressionDeclMap::LookupInModulesDeclVendor(
1092     NameSearchContext &context, ConstString name, unsigned current_id) {
1093   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
1094 
1095   auto *modules_decl_vendor = m_target->GetClangModulesDeclVendor();
1096   if (!modules_decl_vendor)
1097     return;
1098 
1099   bool append = false;
1100   uint32_t max_matches = 1;
1101   std::vector<clang::NamedDecl *> decls;
1102 
1103   if (!modules_decl_vendor->FindDecls(name, append, max_matches, decls))
1104     return;
1105 
1106   assert(!decls.empty() && "FindDecls returned true but no decls?");
1107   clang::NamedDecl *const decl_from_modules = decls[0];
1108 
1109   LLDB_LOG(log,
1110            "  CAS::FEVD[{0}] Matching decl found for "
1111            "\"{1}\" in the modules",
1112            current_id, name);
1113 
1114   clang::Decl *copied_decl = CopyDecl(decl_from_modules);
1115   if (!copied_decl) {
1116     LLDB_LOG(log,
1117              "  CAS::FEVD[{0}] - Couldn't export a "
1118              "declaration from the modules",
1119              current_id);
1120     return;
1121   }
1122 
1123   if (auto copied_function = dyn_cast<clang::FunctionDecl>(copied_decl)) {
1124     MaybeRegisterFunctionBody(copied_function);
1125 
1126     context.AddNamedDecl(copied_function);
1127 
1128     context.m_found.function_with_type_info = true;
1129     context.m_found.function = true;
1130   } else if (auto copied_var = dyn_cast<clang::VarDecl>(copied_decl)) {
1131     context.AddNamedDecl(copied_var);
1132     context.m_found.variable = true;
1133   }
1134 }
1135 
1136 bool ClangExpressionDeclMap::LookupLocalVariable(
1137     NameSearchContext &context, ConstString name, unsigned current_id,
1138     SymbolContext &sym_ctx, CompilerDeclContext &namespace_decl) {
1139   if (sym_ctx.block == nullptr)
1140     return false;
1141 
1142   CompilerDeclContext decl_context = sym_ctx.block->GetDeclContext();
1143   if (!decl_context)
1144     return false;
1145 
1146   // Make sure that the variables are parsed so that we have the
1147   // declarations.
1148   StackFrame *frame = m_parser_vars->m_exe_ctx.GetFramePtr();
1149   VariableListSP vars = frame->GetInScopeVariableList(true);
1150   for (size_t i = 0; i < vars->GetSize(); i++)
1151     vars->GetVariableAtIndex(i)->GetDecl();
1152 
1153   // Search for declarations matching the name. Do not include imported
1154   // decls in the search if we are looking for decls in the artificial
1155   // namespace $__lldb_local_vars.
1156   std::vector<CompilerDecl> found_decls =
1157       decl_context.FindDeclByName(name, namespace_decl.IsValid());
1158 
1159   VariableSP var;
1160   bool variable_found = false;
1161   for (CompilerDecl decl : found_decls) {
1162     for (size_t vi = 0, ve = vars->GetSize(); vi != ve; ++vi) {
1163       VariableSP candidate_var = vars->GetVariableAtIndex(vi);
1164       if (candidate_var->GetDecl() == decl) {
1165         var = candidate_var;
1166         break;
1167       }
1168     }
1169 
1170     if (var && !variable_found) {
1171       variable_found = true;
1172       ValueObjectSP valobj = ValueObjectVariable::Create(frame, var);
1173       AddOneVariable(context, var, valobj, current_id);
1174       context.m_found.variable = true;
1175     }
1176   }
1177   return variable_found;
1178 }
1179 
1180 /// Structure to hold the info needed when comparing function
1181 /// declarations.
1182 namespace {
1183 struct FuncDeclInfo {
1184   ConstString m_name;
1185   CompilerType m_copied_type;
1186   uint32_t m_decl_lvl;
1187   SymbolContext m_sym_ctx;
1188 };
1189 } // namespace
1190 
1191 SymbolContextList ClangExpressionDeclMap::SearchFunctionsInSymbolContexts(
1192     const SymbolContextList &sc_list,
1193     const CompilerDeclContext &frame_decl_context) {
1194   // First, symplify things by looping through the symbol contexts to
1195   // remove unwanted functions and separate out the functions we want to
1196   // compare and prune into a separate list. Cache the info needed about
1197   // the function declarations in a vector for efficiency.
1198   uint32_t num_indices = sc_list.GetSize();
1199   SymbolContextList sc_sym_list;
1200   std::vector<FuncDeclInfo> decl_infos;
1201   decl_infos.reserve(num_indices);
1202   clang::DeclContext *frame_decl_ctx =
1203       (clang::DeclContext *)frame_decl_context.GetOpaqueDeclContext();
1204   ClangASTContext *ast = llvm::dyn_cast_or_null<ClangASTContext>(
1205       frame_decl_context.GetTypeSystem());
1206 
1207   for (uint32_t index = 0; index < num_indices; ++index) {
1208     FuncDeclInfo fdi;
1209     SymbolContext sym_ctx;
1210     sc_list.GetContextAtIndex(index, sym_ctx);
1211 
1212     // We don't know enough about symbols to compare them, but we should
1213     // keep them in the list.
1214     Function *function = sym_ctx.function;
1215     if (!function) {
1216       sc_sym_list.Append(sym_ctx);
1217       continue;
1218     }
1219     // Filter out functions without declaration contexts, as well as
1220     // class/instance methods, since they'll be skipped in the code that
1221     // follows anyway.
1222     CompilerDeclContext func_decl_context = function->GetDeclContext();
1223     if (!func_decl_context ||
1224         func_decl_context.IsClassMethod(nullptr, nullptr, nullptr))
1225       continue;
1226     // We can only prune functions for which we can copy the type.
1227     CompilerType func_clang_type = function->GetType()->GetFullCompilerType();
1228     CompilerType copied_func_type = GuardedCopyType(func_clang_type);
1229     if (!copied_func_type) {
1230       sc_sym_list.Append(sym_ctx);
1231       continue;
1232     }
1233 
1234     fdi.m_sym_ctx = sym_ctx;
1235     fdi.m_name = function->GetName();
1236     fdi.m_copied_type = copied_func_type;
1237     fdi.m_decl_lvl = LLDB_INVALID_DECL_LEVEL;
1238     if (fdi.m_copied_type && func_decl_context) {
1239       // Call CountDeclLevels to get the number of parent scopes we have
1240       // to look through before we find the function declaration. When
1241       // comparing functions of the same type, the one with a lower count
1242       // will be closer to us in the lookup scope and shadows the other.
1243       clang::DeclContext *func_decl_ctx =
1244           (clang::DeclContext *)func_decl_context.GetOpaqueDeclContext();
1245       fdi.m_decl_lvl = ast->CountDeclLevels(frame_decl_ctx, func_decl_ctx,
1246                                             &fdi.m_name, &fdi.m_copied_type);
1247     }
1248     decl_infos.emplace_back(fdi);
1249   }
1250 
1251   // Loop through the functions in our cache looking for matching types,
1252   // then compare their scope levels to see which is closer.
1253   std::multimap<CompilerType, const FuncDeclInfo *> matches;
1254   for (const FuncDeclInfo &fdi : decl_infos) {
1255     const CompilerType t = fdi.m_copied_type;
1256     auto q = matches.find(t);
1257     if (q != matches.end()) {
1258       if (q->second->m_decl_lvl > fdi.m_decl_lvl)
1259         // This function is closer; remove the old set.
1260         matches.erase(t);
1261       else if (q->second->m_decl_lvl < fdi.m_decl_lvl)
1262         // The functions in our set are closer - skip this one.
1263         continue;
1264     }
1265     matches.insert(std::make_pair(t, &fdi));
1266   }
1267 
1268   // Loop through our matches and add their symbol contexts to our list.
1269   SymbolContextList sc_func_list;
1270   for (const auto &q : matches)
1271     sc_func_list.Append(q.second->m_sym_ctx);
1272 
1273   // Rejoin the lists with the functions in front.
1274   sc_func_list.Append(sc_sym_list);
1275   return sc_func_list;
1276 }
1277 
1278 void ClangExpressionDeclMap::LookupFunction(NameSearchContext &context,
1279                                             lldb::ModuleSP module_sp,
1280                                             ConstString name,
1281                                             CompilerDeclContext &namespace_decl,
1282                                             unsigned current_id) {
1283 
1284   Target *target = m_parser_vars->m_exe_ctx.GetTargetPtr();
1285 
1286   std::vector<clang::NamedDecl *> decls_from_modules;
1287 
1288   if (target) {
1289     if (ClangModulesDeclVendor *decl_vendor =
1290             target->GetClangModulesDeclVendor()) {
1291       decl_vendor->FindDecls(name, false, UINT32_MAX, decls_from_modules);
1292     }
1293   }
1294 
1295   const bool include_inlines = false;
1296   SymbolContextList sc_list;
1297   if (namespace_decl && module_sp) {
1298     const bool include_symbols = false;
1299 
1300     module_sp->FindFunctions(name, &namespace_decl, eFunctionNameTypeBase,
1301                              include_symbols, include_inlines, sc_list);
1302   } else if (target && !namespace_decl) {
1303     const bool include_symbols = true;
1304 
1305     // TODO Fix FindFunctions so that it doesn't return
1306     //   instance methods for eFunctionNameTypeBase.
1307 
1308     target->GetImages().FindFunctions(name, eFunctionNameTypeFull,
1309                                       include_symbols, include_inlines,
1310                                       sc_list);
1311   }
1312 
1313   // If we found more than one function, see if we can use the frame's decl
1314   // context to remove functions that are shadowed by other functions which
1315   // match in type but are nearer in scope.
1316   //
1317   // AddOneFunction will not add a function whose type has already been
1318   // added, so if there's another function in the list with a matching type,
1319   // check to see if their decl context is a parent of the current frame's or
1320   // was imported via a and using statement, and pick the best match
1321   // according to lookup rules.
1322   if (sc_list.GetSize() > 1) {
1323     // Collect some info about our frame's context.
1324     StackFrame *frame = m_parser_vars->m_exe_ctx.GetFramePtr();
1325     SymbolContext frame_sym_ctx;
1326     if (frame != nullptr)
1327       frame_sym_ctx = frame->GetSymbolContext(lldb::eSymbolContextFunction |
1328                                               lldb::eSymbolContextBlock);
1329     CompilerDeclContext frame_decl_context =
1330         frame_sym_ctx.block != nullptr ? frame_sym_ctx.block->GetDeclContext()
1331                                        : CompilerDeclContext();
1332 
1333     // We can't do this without a compiler decl context for our frame.
1334     if (frame_decl_context) {
1335       sc_list = SearchFunctionsInSymbolContexts(sc_list, frame_decl_context);
1336     }
1337   }
1338 
1339   if (sc_list.GetSize()) {
1340     Symbol *extern_symbol = nullptr;
1341     Symbol *non_extern_symbol = nullptr;
1342 
1343     for (uint32_t index = 0, num_indices = sc_list.GetSize();
1344          index < num_indices; ++index) {
1345       SymbolContext sym_ctx;
1346       sc_list.GetContextAtIndex(index, sym_ctx);
1347 
1348       if (sym_ctx.function) {
1349         CompilerDeclContext decl_ctx = sym_ctx.function->GetDeclContext();
1350 
1351         if (!decl_ctx)
1352           continue;
1353 
1354         // Filter out class/instance methods.
1355         if (decl_ctx.IsClassMethod(nullptr, nullptr, nullptr))
1356           continue;
1357 
1358         AddOneFunction(context, sym_ctx.function, nullptr, current_id);
1359         context.m_found.function_with_type_info = true;
1360         context.m_found.function = true;
1361       } else if (sym_ctx.symbol) {
1362         if (sym_ctx.symbol->GetType() == eSymbolTypeReExported && target) {
1363           sym_ctx.symbol = sym_ctx.symbol->ResolveReExportedSymbol(*target);
1364           if (sym_ctx.symbol == nullptr)
1365             continue;
1366         }
1367 
1368         if (sym_ctx.symbol->IsExternal())
1369           extern_symbol = sym_ctx.symbol;
1370         else
1371           non_extern_symbol = sym_ctx.symbol;
1372       }
1373     }
1374 
1375     if (!context.m_found.function_with_type_info) {
1376       for (clang::NamedDecl *decl : decls_from_modules) {
1377         if (llvm::isa<clang::FunctionDecl>(decl)) {
1378           clang::NamedDecl *copied_decl =
1379               llvm::cast_or_null<FunctionDecl>(CopyDecl(decl));
1380           if (copied_decl) {
1381             context.AddNamedDecl(copied_decl);
1382             context.m_found.function_with_type_info = true;
1383           }
1384         }
1385       }
1386     }
1387 
1388     if (!context.m_found.function_with_type_info) {
1389       if (extern_symbol) {
1390         AddOneFunction(context, nullptr, extern_symbol, current_id);
1391         context.m_found.function = true;
1392       } else if (non_extern_symbol) {
1393         AddOneFunction(context, nullptr, non_extern_symbol, current_id);
1394         context.m_found.function = true;
1395       }
1396     }
1397   }
1398 }
1399 
1400 void ClangExpressionDeclMap::FindExternalVisibleDecls(
1401     NameSearchContext &context, lldb::ModuleSP module_sp,
1402     CompilerDeclContext &namespace_decl, unsigned int current_id) {
1403   assert(m_ast_context);
1404 
1405   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
1406 
1407   const ConstString name(context.m_decl_name.getAsString().c_str());
1408   if (IgnoreName(name, false))
1409     return;
1410 
1411   // Only look for functions by name out in our symbols if the function doesn't
1412   // start with our phony prefix of '$'
1413   Target *target = m_parser_vars->m_exe_ctx.GetTargetPtr();
1414   StackFrame *frame = m_parser_vars->m_exe_ctx.GetFramePtr();
1415   SymbolContext sym_ctx;
1416   if (frame != nullptr)
1417     sym_ctx = frame->GetSymbolContext(lldb::eSymbolContextFunction |
1418                                       lldb::eSymbolContextBlock);
1419 
1420   // Try the persistent decls, which take precedence over all else.
1421   if (!namespace_decl)
1422     SearchPersistenDecls(context, name, current_id);
1423 
1424   if (name.GetStringRef().startswith("$") && !namespace_decl) {
1425     if (name == "$__lldb_class") {
1426       LookUpLldbClass(context, current_id);
1427       return;
1428     }
1429 
1430     if (name == "$__lldb_objc_class") {
1431       LookUpLldbObjCClass(context, current_id);
1432       return;
1433     }
1434     if (name == g_lldb_local_vars_namespace_cstr) {
1435       LookupLocalVarNamespace(sym_ctx, context);
1436       return;
1437     }
1438 
1439     // any other $__lldb names should be weeded out now
1440     if (name.GetStringRef().startswith("$__lldb"))
1441       return;
1442 
1443     ExpressionVariableSP pvar_sp(
1444         m_parser_vars->m_persistent_vars->GetVariable(name));
1445 
1446     if (pvar_sp) {
1447       AddOneVariable(context, pvar_sp, current_id);
1448       return;
1449     }
1450 
1451     assert(name.GetStringRef().startswith("$"));
1452     llvm::StringRef reg_name = name.GetStringRef().substr(1);
1453 
1454     if (m_parser_vars->m_exe_ctx.GetRegisterContext()) {
1455       const RegisterInfo *reg_info(
1456           m_parser_vars->m_exe_ctx.GetRegisterContext()->GetRegisterInfoByName(
1457               reg_name));
1458 
1459       if (reg_info) {
1460         LLDB_LOGF(log, "  CEDM::FEVD[%u] Found register %s", current_id,
1461                   reg_info->name);
1462 
1463         AddOneRegister(context, reg_info, current_id);
1464       }
1465     }
1466     return;
1467   }
1468 
1469   bool local_var_lookup = !namespace_decl || (namespace_decl.GetName() ==
1470                                               g_lldb_local_vars_namespace_cstr);
1471   if (frame && local_var_lookup)
1472     if (LookupLocalVariable(context, name, current_id, sym_ctx, namespace_decl))
1473       return;
1474 
1475   if (target) {
1476     ValueObjectSP valobj;
1477     VariableSP var;
1478     var =
1479         FindGlobalVariable(*target, module_sp, name, &namespace_decl, nullptr);
1480 
1481     if (var) {
1482       valobj = ValueObjectVariable::Create(target, var);
1483       AddOneVariable(context, var, valobj, current_id);
1484       context.m_found.variable = true;
1485       return;
1486     }
1487   }
1488 
1489   LookupFunction(context, module_sp, name, namespace_decl, current_id);
1490 
1491   // Try the modules next.
1492   if (!context.m_found.function_with_type_info)
1493     LookupInModulesDeclVendor(context, name, current_id);
1494 
1495   if (target && !context.m_found.variable && !namespace_decl) {
1496     // We couldn't find a non-symbol variable for this.  Now we'll hunt for a
1497     // generic data symbol, and -- if it is found -- treat it as a variable.
1498     Status error;
1499 
1500     const Symbol *data_symbol =
1501         m_parser_vars->m_sym_ctx.FindBestGlobalDataSymbol(name, error);
1502 
1503     if (!error.Success()) {
1504       const unsigned diag_id =
1505           m_ast_context->getDiagnostics().getCustomDiagID(
1506               clang::DiagnosticsEngine::Level::Error, "%0");
1507       m_ast_context->getDiagnostics().Report(diag_id) << error.AsCString();
1508     }
1509 
1510     if (data_symbol) {
1511       std::string warning("got name from symbols: ");
1512       warning.append(name.AsCString());
1513       const unsigned diag_id =
1514           m_ast_context->getDiagnostics().getCustomDiagID(
1515               clang::DiagnosticsEngine::Level::Warning, "%0");
1516       m_ast_context->getDiagnostics().Report(diag_id) << warning.c_str();
1517       AddOneGenericVariable(context, *data_symbol, current_id);
1518       context.m_found.variable = true;
1519     }
1520   }
1521 }
1522 
1523 bool ClangExpressionDeclMap::GetVariableValue(VariableSP &var,
1524                                               lldb_private::Value &var_location,
1525                                               TypeFromUser *user_type,
1526                                               TypeFromParser *parser_type) {
1527   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
1528 
1529   Type *var_type = var->GetType();
1530 
1531   if (!var_type) {
1532     if (log)
1533       log->PutCString("Skipped a definition because it has no type");
1534     return false;
1535   }
1536 
1537   CompilerType var_clang_type = var_type->GetFullCompilerType();
1538 
1539   if (!var_clang_type) {
1540     if (log)
1541       log->PutCString("Skipped a definition because it has no Clang type");
1542     return false;
1543   }
1544 
1545   ClangASTContext *clang_ast = llvm::dyn_cast_or_null<ClangASTContext>(
1546       var_type->GetForwardCompilerType().GetTypeSystem());
1547 
1548   if (!clang_ast) {
1549     if (log)
1550       log->PutCString("Skipped a definition because it has no Clang AST");
1551     return false;
1552   }
1553 
1554   ASTContext *ast = clang_ast->getASTContext();
1555 
1556   if (!ast) {
1557     if (log)
1558       log->PutCString(
1559           "There is no AST context for the current execution context");
1560     return false;
1561   }
1562 
1563   DWARFExpression &var_location_expr = var->LocationExpression();
1564 
1565   Target *target = m_parser_vars->m_exe_ctx.GetTargetPtr();
1566   Status err;
1567 
1568   if (var->GetLocationIsConstantValueData()) {
1569     DataExtractor const_value_extractor;
1570 
1571     if (var_location_expr.GetExpressionData(const_value_extractor)) {
1572       var_location = Value(const_value_extractor.GetDataStart(),
1573                            const_value_extractor.GetByteSize());
1574       var_location.SetValueType(Value::eValueTypeHostAddress);
1575     } else {
1576       LLDB_LOGF(log, "Error evaluating constant variable: %s", err.AsCString());
1577       return false;
1578     }
1579   }
1580 
1581   CompilerType type_to_use = GuardedCopyType(var_clang_type);
1582 
1583   if (!type_to_use) {
1584     LLDB_LOGF(log,
1585               "Couldn't copy a variable's type into the parser's AST context");
1586 
1587     return false;
1588   }
1589 
1590   if (parser_type)
1591     *parser_type = TypeFromParser(type_to_use);
1592 
1593   if (var_location.GetContextType() == Value::eContextTypeInvalid)
1594     var_location.SetCompilerType(type_to_use);
1595 
1596   if (var_location.GetValueType() == Value::eValueTypeFileAddress) {
1597     SymbolContext var_sc;
1598     var->CalculateSymbolContext(&var_sc);
1599 
1600     if (!var_sc.module_sp)
1601       return false;
1602 
1603     Address so_addr(var_location.GetScalar().ULongLong(),
1604                     var_sc.module_sp->GetSectionList());
1605 
1606     lldb::addr_t load_addr = so_addr.GetLoadAddress(target);
1607 
1608     if (load_addr != LLDB_INVALID_ADDRESS) {
1609       var_location.GetScalar() = load_addr;
1610       var_location.SetValueType(Value::eValueTypeLoadAddress);
1611     }
1612   }
1613 
1614   if (user_type)
1615     *user_type = TypeFromUser(var_clang_type);
1616 
1617   return true;
1618 }
1619 
1620 void ClangExpressionDeclMap::AddOneVariable(NameSearchContext &context,
1621                                             VariableSP var,
1622                                             ValueObjectSP valobj,
1623                                             unsigned int current_id) {
1624   assert(m_parser_vars.get());
1625 
1626   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
1627 
1628   TypeFromUser ut;
1629   TypeFromParser pt;
1630   Value var_location;
1631 
1632   if (!GetVariableValue(var, var_location, &ut, &pt))
1633     return;
1634 
1635   clang::QualType parser_opaque_type =
1636       QualType::getFromOpaquePtr(pt.GetOpaqueQualType());
1637 
1638   if (parser_opaque_type.isNull())
1639     return;
1640 
1641   if (const clang::Type *parser_type = parser_opaque_type.getTypePtr()) {
1642     if (const TagType *tag_type = dyn_cast<TagType>(parser_type))
1643       CompleteType(tag_type->getDecl());
1644     if (const ObjCObjectPointerType *objc_object_ptr_type =
1645             dyn_cast<ObjCObjectPointerType>(parser_type))
1646       CompleteType(objc_object_ptr_type->getInterfaceDecl());
1647   }
1648 
1649   bool is_reference = pt.IsReferenceType();
1650 
1651   NamedDecl *var_decl = nullptr;
1652   if (is_reference)
1653     var_decl = context.AddVarDecl(pt);
1654   else
1655     var_decl = context.AddVarDecl(pt.GetLValueReferenceType());
1656 
1657   std::string decl_name(context.m_decl_name.getAsString());
1658   ConstString entity_name(decl_name.c_str());
1659   ClangExpressionVariable *entity(new ClangExpressionVariable(valobj));
1660   m_found_entities.AddNewlyConstructedVariable(entity);
1661 
1662   assert(entity);
1663   entity->EnableParserVars(GetParserID());
1664   ClangExpressionVariable::ParserVars *parser_vars =
1665       entity->GetParserVars(GetParserID());
1666   parser_vars->m_parser_type = pt;
1667   parser_vars->m_named_decl = var_decl;
1668   parser_vars->m_llvm_value = nullptr;
1669   parser_vars->m_lldb_value = var_location;
1670   parser_vars->m_lldb_var = var;
1671 
1672   if (is_reference)
1673     entity->m_flags |= ClangExpressionVariable::EVTypeIsReference;
1674 
1675   LLDB_LOG(log,
1676            "  CEDM::FEVD[{0}] Found variable {1}, returned\n{2} (original {3})",
1677            current_id, decl_name, ClangUtil::DumpDecl(var_decl),
1678            ClangUtil::ToString(ut));
1679 }
1680 
1681 void ClangExpressionDeclMap::AddOneVariable(NameSearchContext &context,
1682                                             ExpressionVariableSP &pvar_sp,
1683                                             unsigned int current_id) {
1684   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
1685 
1686   TypeFromUser user_type(
1687       llvm::cast<ClangExpressionVariable>(pvar_sp.get())->GetTypeFromUser());
1688 
1689   TypeFromParser parser_type(GuardedCopyType(user_type));
1690 
1691   if (!parser_type.GetOpaqueQualType()) {
1692     LLDB_LOGF(log, "  CEDM::FEVD[%u] Couldn't import type for pvar %s",
1693               current_id, pvar_sp->GetName().GetCString());
1694     return;
1695   }
1696 
1697   NamedDecl *var_decl =
1698       context.AddVarDecl(parser_type.GetLValueReferenceType());
1699 
1700   llvm::cast<ClangExpressionVariable>(pvar_sp.get())
1701       ->EnableParserVars(GetParserID());
1702   ClangExpressionVariable::ParserVars *parser_vars =
1703       llvm::cast<ClangExpressionVariable>(pvar_sp.get())
1704           ->GetParserVars(GetParserID());
1705   parser_vars->m_parser_type = parser_type;
1706   parser_vars->m_named_decl = var_decl;
1707   parser_vars->m_llvm_value = nullptr;
1708   parser_vars->m_lldb_value.Clear();
1709 
1710   LLDB_LOG(log, "  CEDM::FEVD[{0}] Added pvar {1}, returned\n{2}", current_id,
1711            pvar_sp->GetName(), ClangUtil::DumpDecl(var_decl));
1712 }
1713 
1714 void ClangExpressionDeclMap::AddOneGenericVariable(NameSearchContext &context,
1715                                                    const Symbol &symbol,
1716                                                    unsigned int current_id) {
1717   assert(m_parser_vars.get());
1718 
1719   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
1720 
1721   Target *target = m_parser_vars->m_exe_ctx.GetTargetPtr();
1722 
1723   if (target == nullptr)
1724     return;
1725 
1726   ClangASTContext *scratch_ast_context = target->GetScratchClangASTContext();
1727 
1728   TypeFromUser user_type(scratch_ast_context->GetBasicType(eBasicTypeVoid)
1729                              .GetPointerType()
1730                              .GetLValueReferenceType());
1731   TypeFromParser parser_type(m_clang_ast_context->GetBasicType(eBasicTypeVoid)
1732                                  .GetPointerType()
1733                                  .GetLValueReferenceType());
1734   NamedDecl *var_decl = context.AddVarDecl(parser_type);
1735 
1736   std::string decl_name(context.m_decl_name.getAsString());
1737   ConstString entity_name(decl_name.c_str());
1738   ClangExpressionVariable *entity(new ClangExpressionVariable(
1739       m_parser_vars->m_exe_ctx.GetBestExecutionContextScope(), entity_name,
1740       user_type, m_parser_vars->m_target_info.byte_order,
1741       m_parser_vars->m_target_info.address_byte_size));
1742   m_found_entities.AddNewlyConstructedVariable(entity);
1743 
1744   entity->EnableParserVars(GetParserID());
1745   ClangExpressionVariable::ParserVars *parser_vars =
1746       entity->GetParserVars(GetParserID());
1747 
1748   const Address symbol_address = symbol.GetAddress();
1749   lldb::addr_t symbol_load_addr = symbol_address.GetLoadAddress(target);
1750 
1751   // parser_vars->m_lldb_value.SetContext(Value::eContextTypeClangType,
1752   // user_type.GetOpaqueQualType());
1753   parser_vars->m_lldb_value.SetCompilerType(user_type);
1754   parser_vars->m_lldb_value.GetScalar() = symbol_load_addr;
1755   parser_vars->m_lldb_value.SetValueType(Value::eValueTypeLoadAddress);
1756 
1757   parser_vars->m_parser_type = parser_type;
1758   parser_vars->m_named_decl = var_decl;
1759   parser_vars->m_llvm_value = nullptr;
1760   parser_vars->m_lldb_sym = &symbol;
1761 
1762   LLDB_LOG(log, "  CEDM::FEVD[{0}] Found variable {1}, returned\n{2}",
1763            current_id, decl_name, ClangUtil::DumpDecl(var_decl));
1764 }
1765 
1766 void ClangExpressionDeclMap::AddOneRegister(NameSearchContext &context,
1767                                             const RegisterInfo *reg_info,
1768                                             unsigned int current_id) {
1769   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
1770 
1771   CompilerType clang_type =
1772       m_clang_ast_context->GetBuiltinTypeForEncodingAndBitSize(
1773           reg_info->encoding, reg_info->byte_size * 8);
1774 
1775   if (!clang_type) {
1776     LLDB_LOGF(log, "  Tried to add a type for %s, but couldn't get one",
1777               context.m_decl_name.getAsString().c_str());
1778     return;
1779   }
1780 
1781   TypeFromParser parser_clang_type(clang_type);
1782 
1783   NamedDecl *var_decl = context.AddVarDecl(parser_clang_type);
1784 
1785   ClangExpressionVariable *entity(new ClangExpressionVariable(
1786       m_parser_vars->m_exe_ctx.GetBestExecutionContextScope(),
1787       m_parser_vars->m_target_info.byte_order,
1788       m_parser_vars->m_target_info.address_byte_size));
1789   m_found_entities.AddNewlyConstructedVariable(entity);
1790 
1791   std::string decl_name(context.m_decl_name.getAsString());
1792   entity->SetName(ConstString(decl_name.c_str()));
1793   entity->SetRegisterInfo(reg_info);
1794   entity->EnableParserVars(GetParserID());
1795   ClangExpressionVariable::ParserVars *parser_vars =
1796       entity->GetParserVars(GetParserID());
1797   parser_vars->m_parser_type = parser_clang_type;
1798   parser_vars->m_named_decl = var_decl;
1799   parser_vars->m_llvm_value = nullptr;
1800   parser_vars->m_lldb_value.Clear();
1801   entity->m_flags |= ClangExpressionVariable::EVBareRegister;
1802 
1803   LLDB_LOG(log, "  CEDM::FEVD[{0}] Added register {1}, returned\n{2}",
1804            current_id, context.m_decl_name.getAsString(),
1805            ClangUtil::DumpDecl(var_decl));
1806 }
1807 
1808 void ClangExpressionDeclMap::AddOneFunction(NameSearchContext &context,
1809                                             Function *function, Symbol *symbol,
1810                                             unsigned int current_id) {
1811   assert(m_parser_vars.get());
1812 
1813   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
1814 
1815   NamedDecl *function_decl = nullptr;
1816   Address fun_address;
1817   CompilerType function_clang_type;
1818 
1819   bool is_indirect_function = false;
1820 
1821   if (function) {
1822     Type *function_type = function->GetType();
1823 
1824     const auto lang = function->GetCompileUnit()->GetLanguage();
1825     const auto name = function->GetMangled().GetMangledName().AsCString();
1826     const bool extern_c = (Language::LanguageIsC(lang) &&
1827                            !CPlusPlusLanguage::IsCPPMangledName(name)) ||
1828                           (Language::LanguageIsObjC(lang) &&
1829                            !Language::LanguageIsCPlusPlus(lang));
1830 
1831     if (!extern_c) {
1832       TypeSystem *type_system = function->GetDeclContext().GetTypeSystem();
1833       if (llvm::isa<ClangASTContext>(type_system)) {
1834         clang::DeclContext *src_decl_context =
1835             (clang::DeclContext *)function->GetDeclContext()
1836                 .GetOpaqueDeclContext();
1837         clang::FunctionDecl *src_function_decl =
1838             llvm::dyn_cast_or_null<clang::FunctionDecl>(src_decl_context);
1839         if (src_function_decl &&
1840             src_function_decl->getTemplateSpecializationInfo()) {
1841           clang::FunctionTemplateDecl *function_template =
1842               src_function_decl->getTemplateSpecializationInfo()->getTemplate();
1843           clang::FunctionTemplateDecl *copied_function_template =
1844               llvm::dyn_cast_or_null<clang::FunctionTemplateDecl>(
1845                   CopyDecl(function_template));
1846           if (copied_function_template) {
1847             if (log) {
1848               StreamString ss;
1849 
1850               function->DumpSymbolContext(&ss);
1851 
1852               LLDB_LOG(log,
1853                        "  CEDM::FEVD[{0}] Imported decl for function template"
1854                        " {1} (description {2}), returned\n{3}",
1855                        current_id, copied_function_template->getNameAsString(),
1856                        ss.GetData(),
1857                        ClangUtil::DumpDecl(copied_function_template));
1858             }
1859 
1860             context.AddNamedDecl(copied_function_template);
1861           }
1862         } else if (src_function_decl) {
1863           if (clang::FunctionDecl *copied_function_decl =
1864                   llvm::dyn_cast_or_null<clang::FunctionDecl>(
1865                       CopyDecl(src_function_decl))) {
1866             if (log) {
1867               StreamString ss;
1868 
1869               function->DumpSymbolContext(&ss);
1870 
1871               LLDB_LOG(log,
1872                        "  CEDM::FEVD[{0}]] Imported decl for function {1} "
1873                        "(description {2}), returned\n{3}",
1874                        current_id, copied_function_decl->getNameAsString(),
1875                        ss.GetData(), ClangUtil::DumpDecl(copied_function_decl));
1876             }
1877 
1878             context.AddNamedDecl(copied_function_decl);
1879             return;
1880           } else {
1881             if (log) {
1882               LLDB_LOGF(log, "  Failed to import the function decl for '%s'",
1883                         src_function_decl->getName().str().c_str());
1884             }
1885           }
1886         }
1887       }
1888     }
1889 
1890     if (!function_type) {
1891       if (log)
1892         log->PutCString("  Skipped a function because it has no type");
1893       return;
1894     }
1895 
1896     function_clang_type = function_type->GetFullCompilerType();
1897 
1898     if (!function_clang_type) {
1899       if (log)
1900         log->PutCString("  Skipped a function because it has no Clang type");
1901       return;
1902     }
1903 
1904     fun_address = function->GetAddressRange().GetBaseAddress();
1905 
1906     CompilerType copied_function_type = GuardedCopyType(function_clang_type);
1907     if (copied_function_type) {
1908       function_decl = context.AddFunDecl(copied_function_type, extern_c);
1909 
1910       if (!function_decl) {
1911         if (log) {
1912           LLDB_LOGF(
1913               log,
1914               "  Failed to create a function decl for '%s' {0x%8.8" PRIx64 "}",
1915               function_type->GetName().GetCString(), function_type->GetID());
1916         }
1917 
1918         return;
1919       }
1920     } else {
1921       // We failed to copy the type we found
1922       if (log) {
1923         LLDB_LOGF(log,
1924                   "  Failed to import the function type '%s' {0x%8.8" PRIx64
1925                   "} into the expression parser AST contenxt",
1926                   function_type->GetName().GetCString(),
1927                   function_type->GetID());
1928       }
1929 
1930       return;
1931     }
1932   } else if (symbol) {
1933     fun_address = symbol->GetAddress();
1934     function_decl = context.AddGenericFunDecl();
1935     is_indirect_function = symbol->IsIndirect();
1936   } else {
1937     if (log)
1938       log->PutCString("  AddOneFunction called with no function and no symbol");
1939     return;
1940   }
1941 
1942   Target *target = m_parser_vars->m_exe_ctx.GetTargetPtr();
1943 
1944   lldb::addr_t load_addr =
1945       fun_address.GetCallableLoadAddress(target, is_indirect_function);
1946 
1947   ClangExpressionVariable *entity(new ClangExpressionVariable(
1948       m_parser_vars->m_exe_ctx.GetBestExecutionContextScope(),
1949       m_parser_vars->m_target_info.byte_order,
1950       m_parser_vars->m_target_info.address_byte_size));
1951   m_found_entities.AddNewlyConstructedVariable(entity);
1952 
1953   std::string decl_name(context.m_decl_name.getAsString());
1954   entity->SetName(ConstString(decl_name.c_str()));
1955   entity->SetCompilerType(function_clang_type);
1956   entity->EnableParserVars(GetParserID());
1957 
1958   ClangExpressionVariable::ParserVars *parser_vars =
1959       entity->GetParserVars(GetParserID());
1960 
1961   if (load_addr != LLDB_INVALID_ADDRESS) {
1962     parser_vars->m_lldb_value.SetValueType(Value::eValueTypeLoadAddress);
1963     parser_vars->m_lldb_value.GetScalar() = load_addr;
1964   } else {
1965     // We have to try finding a file address.
1966 
1967     lldb::addr_t file_addr = fun_address.GetFileAddress();
1968 
1969     parser_vars->m_lldb_value.SetValueType(Value::eValueTypeFileAddress);
1970     parser_vars->m_lldb_value.GetScalar() = file_addr;
1971   }
1972 
1973   parser_vars->m_named_decl = function_decl;
1974   parser_vars->m_llvm_value = nullptr;
1975 
1976   if (log) {
1977     StreamString ss;
1978 
1979     fun_address.Dump(&ss,
1980                      m_parser_vars->m_exe_ctx.GetBestExecutionContextScope(),
1981                      Address::DumpStyleResolvedDescription);
1982 
1983     LLDB_LOG(log,
1984              "  CEDM::FEVD[{0}] Found {1} function {2} (description {3}), "
1985              "returned\n{4}",
1986              current_id, (function ? "specific" : "generic"), decl_name,
1987              ss.GetData(), ClangUtil::DumpDecl(function_decl));
1988   }
1989 }
1990 
1991 void ClangExpressionDeclMap::AddThisType(NameSearchContext &context,
1992                                          const TypeFromUser &ut,
1993                                          unsigned int current_id) {
1994   CompilerType copied_clang_type = GuardedCopyType(ut);
1995 
1996   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
1997 
1998   if (!copied_clang_type) {
1999     if (log)
2000       LLDB_LOGF(
2001           log,
2002           "ClangExpressionDeclMap::AddThisType - Couldn't import the type");
2003 
2004     return;
2005   }
2006 
2007   if (copied_clang_type.IsAggregateType() &&
2008       copied_clang_type.GetCompleteType()) {
2009     CompilerType void_clang_type =
2010         m_clang_ast_context->GetBasicType(eBasicTypeVoid);
2011     CompilerType void_ptr_clang_type = void_clang_type.GetPointerType();
2012 
2013     CompilerType method_type = ClangASTContext::CreateFunctionType(
2014         m_ast_context, void_clang_type, &void_ptr_clang_type, 1, false, 0);
2015 
2016     const bool is_virtual = false;
2017     const bool is_static = false;
2018     const bool is_inline = false;
2019     const bool is_explicit = false;
2020     const bool is_attr_used = true;
2021     const bool is_artificial = false;
2022 
2023     CXXMethodDecl *method_decl = m_clang_ast_context->AddMethodToCXXRecordType(
2024         copied_clang_type.GetOpaqueQualType(), "$__lldb_expr", nullptr,
2025         method_type, lldb::eAccessPublic, is_virtual, is_static, is_inline,
2026         is_explicit, is_attr_used, is_artificial);
2027 
2028     LLDB_LOG(log,
2029              "  CEDM::AddThisType Added function $__lldb_expr "
2030              "(description {0}) for this type\n{1}",
2031              ClangUtil::ToString(copied_clang_type),
2032              ClangUtil::DumpDecl(method_decl));
2033   }
2034 
2035   if (!copied_clang_type.IsValid())
2036     return;
2037 
2038   TypeSourceInfo *type_source_info = m_ast_context->getTrivialTypeSourceInfo(
2039       QualType::getFromOpaquePtr(copied_clang_type.GetOpaqueQualType()));
2040 
2041   if (!type_source_info)
2042     return;
2043 
2044   // Construct a typedef type because if "*this" is a templated type we can't
2045   // just return ClassTemplateSpecializationDecls in response to name queries.
2046   // Using a typedef makes this much more robust.
2047 
2048   TypedefDecl *typedef_decl = TypedefDecl::Create(
2049       *m_ast_context, m_ast_context->getTranslationUnitDecl(), SourceLocation(),
2050       SourceLocation(), context.m_decl_name.getAsIdentifierInfo(),
2051       type_source_info);
2052 
2053   if (!typedef_decl)
2054     return;
2055 
2056   context.AddNamedDecl(typedef_decl);
2057 
2058   return;
2059 }
2060 
2061 void ClangExpressionDeclMap::AddOneType(NameSearchContext &context,
2062                                         const TypeFromUser &ut,
2063                                         unsigned int current_id) {
2064   CompilerType copied_clang_type = GuardedCopyType(ut);
2065 
2066   if (!copied_clang_type) {
2067     Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
2068 
2069     if (log)
2070       LLDB_LOGF(
2071           log, "ClangExpressionDeclMap::AddOneType - Couldn't import the type");
2072 
2073     return;
2074   }
2075 
2076   context.AddTypeDecl(copied_clang_type);
2077 }
2078