Added support for -gmodule debugging when debug info is left in the .o files on Darwin.

This is done by finding the types that are forward declarations that come from a module, and loading that module's debug info in a separate lldb_private::Module, and copying the type over into the current module using a ClangASTImporter object. ClangASTImporter objects are already used to copy types from on clang::ASTContext to another for expressions so the type copying code has been around for a while.

A new FindTypes variant was added to SymbolVendor and SymbolFile:

size_t
SymbolVendor::FindTypes (const std::vector<CompilerContext> &context, bool append, TypeMap& types);

size_t
SymbolVendor::FindTypes (const std::vector<CompilerContext> &context, bool append, TypeMap& types);

The CompilerContext is a way to represent the exact context of a type and pass it through an agnostic API boundary so that we can find that exact context elsewhere in another file. This was required here because we can have a module that has submodules, both of which have a "foo" type.

I am not able to add tests for this yet as we currently don't build our C/C++/ObjC binaries with the clang binary that we build. There are some driver issues where it can't find the header files for the C and C++ standard library which makes compiling these tests hard. We can't also guarantee that if we are building with clang that it supporst the exact format of -gmodule debugging that we are trying to test. We have had other versions of clang that had a different implementation of -gmodule debugging that we are no longer supporting, so we can't enable tests if we are building with clang without compiling something and looking at the structure of the DWARF that was generated to ensure that it is the format we can actually use.

llvm-svn: 254476

1 files changed, 145 insertions, 30 deletions

diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
index 70293384e7f..fd254ad9c29 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
@@ -1077,9 +1077,9 @@ SymbolFileDWARF::ParseImportedModules (const lldb_private::SymbolContext &sc, st
         if (ClangModulesDeclVendor::LanguageSupportsClangModules(sc.comp_unit->GetLanguage()))
         {
             UpdateExternalModuleListIfNeeded();
-            for (const std::pair<uint64_t, const ClangModuleInfo> &external_type_module : m_external_type_modules)
+            for (const auto &pair : m_external_type_modules)
             {
-                imported_modules.push_back(external_type_module.second.m_name);
+                imported_modules.push_back(pair.first);
             }
         }
     }
@@ -1515,13 +1515,32 @@ bool
 SymbolFileDWARF::HasForwardDeclForClangType (const CompilerType &compiler_type)
 {
     CompilerType compiler_type_no_qualifiers = ClangASTContext::RemoveFastQualifiers(compiler_type);
-    return GetForwardDeclClangTypeToDie().count (compiler_type_no_qualifiers.GetOpaqueQualType());
+    if (GetForwardDeclClangTypeToDie().count (compiler_type_no_qualifiers.GetOpaqueQualType()))
+    {
+        return true;
+    }
+    TypeSystem *type_system = compiler_type.GetTypeSystem();
+    if (type_system)
+    {
+        DWARFASTParser *dwarf_ast = type_system->GetDWARFParser();
+        if (dwarf_ast)
+            return dwarf_ast->CanCompleteType(compiler_type);
+    }
+    return false;
 }
 
 
 bool
 SymbolFileDWARF::CompleteType (CompilerType &compiler_type)
 {
+    TypeSystem *type_system = compiler_type.GetTypeSystem();
+    if (type_system)
+    {
+        DWARFASTParser *dwarf_ast = type_system->GetDWARFParser();
+        if (dwarf_ast && dwarf_ast->CanCompleteType(compiler_type))
+            return dwarf_ast->CompleteType(compiler_type);
+    }
+
     // We have a struct/union/class/enum that needs to be fully resolved.
     CompilerType compiler_type_no_qualifiers = ClangASTContext::RemoveFastQualifiers(compiler_type);
     auto die_it = GetForwardDeclClangTypeToDie().find (compiler_type_no_qualifiers.GetOpaqueQualType());
@@ -1641,6 +1660,17 @@ SymbolFileDWARF::GetFunction (const DWARFDIE &die, SymbolContext& sc)
     return false;
 }
 
+lldb::ModuleSP
+SymbolFileDWARF::GetDWOModule (ConstString name)
+{
+    UpdateExternalModuleListIfNeeded();
+    const auto &pos = m_external_type_modules.find(name);
+    if (pos != m_external_type_modules.end())
+        return pos->second;
+    else
+        return lldb::ModuleSP();
+}
+
 void
 SymbolFileDWARF::UpdateExternalModuleListIfNeeded()
 {
@@ -1658,37 +1688,24 @@ SymbolFileDWARF::UpdateExternalModuleListIfNeeded()
         const DWARFDIE die = dwarf_cu->GetCompileUnitDIEOnly();
         if (die && die.HasChildren() == false)
         {
-            const uint64_t name_strp = die.GetAttributeValueAsUnsigned (DW_AT_name, UINT64_MAX);
-            const uint64_t dwo_path_strp = die.GetAttributeValueAsUnsigned (DW_AT_GNU_dwo_name, UINT64_MAX);
-            
-            if (name_strp != UINT64_MAX)
+            const char *name = die.GetAttributeValueAsString(DW_AT_name, nullptr);
+
+            if (name)
             {
-                if (m_external_type_modules.find(dwo_path_strp) == m_external_type_modules.end())
+                ConstString const_name(name);
+                if (m_external_type_modules.find(const_name) == m_external_type_modules.end())
                 {
-                    const char *name = get_debug_str_data().PeekCStr(name_strp);
-                    const char *dwo_path = get_debug_str_data().PeekCStr(dwo_path_strp);
-                    if (name || dwo_path)
+                    ModuleSP module_sp;
+                    const char *dwo_path = die.GetAttributeValueAsString(DW_AT_GNU_dwo_name, nullptr);
+                    if (dwo_path)
                     {
-                        ModuleSP module_sp;
-                        if (dwo_path)
-                        {
-                            ModuleSpec dwo_module_spec;
-                            dwo_module_spec.GetFileSpec().SetFile(dwo_path, false);
-                            dwo_module_spec.GetArchitecture() = m_obj_file->GetModule()->GetArchitecture();
-                            //printf ("Loading dwo = '%s'\n", dwo_path);
-                            Error error = ModuleList::GetSharedModule (dwo_module_spec, module_sp, NULL, NULL, NULL);
-                        }
-                        
-                        if (dwo_path_strp != LLDB_INVALID_UID)
-                        {
-                            m_external_type_modules[dwo_path_strp] = ClangModuleInfo { ConstString(name), module_sp };
-                        }
-                        else
-                        {
-                            // This hack should be removed promptly once clang emits both.
-                            m_external_type_modules[name_strp] = ClangModuleInfo { ConstString(name), module_sp };
-                        }
+                        ModuleSpec dwo_module_spec;
+                        dwo_module_spec.GetFileSpec().SetFile(dwo_path, false);
+                        dwo_module_spec.GetArchitecture() = m_obj_file->GetModule()->GetArchitecture();
+                        //printf ("Loading dwo = '%s'\n", dwo_path);
+                        Error error = ModuleList::GetSharedModule (dwo_module_spec, module_sp, NULL, NULL, NULL);
                     }
+                    m_external_type_modules[const_name] = module_sp;
                 }
             }
         }
@@ -2970,6 +2987,104 @@ SymbolFileDWARF::FindTypes (const SymbolContext& sc,
         }
         return num_matches;
     }
+    else
+    {
+        UpdateExternalModuleListIfNeeded();
+
+        for (const auto &pair : m_external_type_modules)
+        {
+            ModuleSP external_module_sp = pair.second;
+            if (external_module_sp)
+            {
+                SymbolVendor *sym_vendor = external_module_sp->GetSymbolVendor();
+                if (sym_vendor)
+                {
+                    const uint32_t num_external_matches = sym_vendor->FindTypes (sc,
+                                                                                 name,
+                                                                                 parent_decl_ctx,
+                                                                                 append,
+                                                                                 max_matches,
+                                                                                 types);
+                    if (num_external_matches)
+                        return num_external_matches;
+                }
+            }
+        }
+    }
+
+    return 0;
+}
+
+
+size_t
+SymbolFileDWARF::FindTypes (const std::vector<CompilerContext> &context,
+                            bool append,
+                            TypeMap& types)
+{
+    if (!append)
+        types.Clear();
+
+    if (context.empty())
+        return 0;
+
+    DIEArray die_offsets;
+
+    ConstString name = context.back().name;
+
+    if (m_using_apple_tables)
+    {
+        if (m_apple_types_ap.get())
+        {
+            const char *name_cstr = name.GetCString();
+            m_apple_types_ap->FindByName (name_cstr, die_offsets);
+        }
+    }
+    else
+    {
+        if (!m_indexed)
+            Index ();
+
+        m_type_index.Find (name, die_offsets);
+    }
+
+    const size_t num_die_matches = die_offsets.size();
+
+    if (num_die_matches)
+    {
+        size_t num_matches = 0;
+        DWARFDebugInfo* debug_info = DebugInfo();
+        for (size_t i=0; i<num_die_matches; ++i)
+        {
+            const DIERef& die_ref = die_offsets[i];
+            DWARFDIE die = debug_info->GetDIE (die_ref);
+
+            if (die)
+            {
+                std::vector<CompilerContext> die_context;
+                die.GetDWOContext(die_context);
+                if (die_context != context)
+                    continue;
+
+                Type *matching_type = ResolveType (die, true, true);
+                if (matching_type)
+                {
+                    // We found a type pointer, now find the shared pointer form our type list
+                    types.InsertUnique (matching_type->shared_from_this());
+                    ++num_matches;
+                }
+            }
+            else
+            {
+                if (m_using_apple_tables)
+                {
+                    GetObjectFile()->GetModule()->ReportErrorIfModifyDetected ("the DWARF debug information has been modified (.apple_types accelerator table had bad die 0x%8.8x for '%s')\n",
+                                                                               die_ref.die_offset, name.GetCString());
+                }
+            }
+
+        }
+        return num_matches;
+    }
     return 0;
 }