[lldb][TypeSystemClang] Make AsmLabel parameter a llvm::StringRef (#151355)

Split out from #148877

This patch prepares `TypeSystemClang` APIs to take `AsmLabel`s which
concatenated strings (hence `std::string`) instead of a plain `const
char*`.

Author: Michael137

lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionDeclMap.cpp

@@ -1991,7 +1991,7 @@ void ClangExpressionDeclMap::AddContextClassType(NameSearchContext &context,
     const bool is_artificial = false;
 
     CXXMethodDecl *method_decl = m_clang_ast_context->AddMethodToCXXRecordType(
-        copied_clang_type.GetOpaqueQualType(), "$__lldb_expr", nullptr,
+        copied_clang_type.GetOpaqueQualType(), "$__lldb_expr", /*asm_label=*/{},
         method_type, lldb::eAccessPublic, is_virtual, is_static, is_inline,
         is_explicit, is_attr_used, is_artificial);
 

lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp

@@ -249,6 +249,14 @@ static unsigned GetCXXMethodCVQuals(const DWARFDIE &subprogram,
   return cv_quals;
 }
 
+static std::string MakeLLDBFuncAsmLabel(const DWARFDIE &die) {
+  char const *name = die.GetMangledName(/*substitute_name_allowed*/ false);
+  if (!name)
+    return {};
+
+  return name;
+}
+
 TypeSP DWARFASTParserClang::ParseTypeFromClangModule(const SymbolContext &sc,
                                                      const DWARFDIE &die,
                                                      Log *log) {
@@ -1231,7 +1239,7 @@ std::pair<bool, TypeSP> DWARFASTParserClang::ParseCXXMethod(
 
   clang::CXXMethodDecl *cxx_method_decl = m_ast.AddMethodToCXXRecordType(
       class_opaque_type.GetOpaqueQualType(), attrs.name.GetCString(),
-      attrs.mangled_name, clang_type, accessibility, attrs.is_virtual,
+      MakeLLDBFuncAsmLabel(die), clang_type, accessibility, attrs.is_virtual,
       is_static, attrs.is_inline, attrs.is_explicit, is_attr_used,
       attrs.is_artificial);
 
@@ -1384,7 +1392,7 @@ DWARFASTParserClang::ParseSubroutine(const DWARFDIE &die,
             ignore_containing_context ? m_ast.GetTranslationUnitDecl()
                                       : containing_decl_ctx,
             GetOwningClangModule(die), name, clang_type, attrs.storage,
-            attrs.is_inline);
+            attrs.is_inline, MakeLLDBFuncAsmLabel(die));
         std::free(name_buf);
 
         if (has_template_params) {
@@ -1394,7 +1402,7 @@ DWARFASTParserClang::ParseSubroutine(const DWARFDIE &die,
               ignore_containing_context ? m_ast.GetTranslationUnitDecl()
                                         : containing_decl_ctx,
               GetOwningClangModule(die), attrs.name.GetStringRef(), clang_type,
-              attrs.storage, attrs.is_inline);
+              attrs.storage, attrs.is_inline, /*asm_label=*/{});
           clang::FunctionTemplateDecl *func_template_decl =
               m_ast.CreateFunctionTemplateDecl(
                   containing_decl_ctx, GetOwningClangModule(die),
@@ -1406,20 +1414,6 @@ DWARFASTParserClang::ParseSubroutine(const DWARFDIE &die,
         lldbassert(function_decl);
 
         if (function_decl) {
-          // Attach an asm(<mangled_name>) label to the FunctionDecl.
-          // This ensures that clang::CodeGen emits function calls
-          // using symbols that are mangled according to the DW_AT_linkage_name.
-          // If we didn't do this, the external symbols wouldn't exactly
-          // match the mangled name LLDB knows about and the IRExecutionUnit
-          // would have to fall back to searching object files for
-          // approximately matching function names. The motivating
-          // example is generating calls to ABI-tagged template functions.
-          // This is done separately for member functions in
-          // AddMethodToCXXRecordType.
-          if (attrs.mangled_name)
-            function_decl->addAttr(clang::AsmLabelAttr::CreateImplicit(
-                m_ast.getASTContext(), attrs.mangled_name, /*literal=*/false));
-
           LinkDeclContextToDIE(function_decl, die);
 
           const clang::FunctionProtoType *function_prototype(

lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp

@@ -88,7 +88,7 @@ struct CreateMethodDecl : public TypeVisitorCallbacks {
                          MethodOptions::CompilerGenerated;
     function_decl = m_clang.AddMethodToCXXRecordType(
         parent_ty, proc_name,
-        /*mangled_name=*/nullptr, func_ct, /*access=*/access_type,
+        /*asm_label=*/{}, func_ct, /*access=*/access_type,
         /*is_virtual=*/is_virtual, /*is_static=*/is_static,
         /*is_inline=*/false, /*is_explicit=*/false,
         /*is_attr_used=*/false, /*is_artificial=*/is_artificial);
@@ -903,7 +903,7 @@ PdbAstBuilder::CreateFunctionDecl(PdbCompilandSymId func_id,
     if (!function_decl) {
       function_decl = m_clang.AddMethodToCXXRecordType(
           parent_opaque_ty, func_name,
-          /*mangled_name=*/nullptr, func_ct,
+          /*asm_label=*/{}, func_ct,
           /*access=*/lldb::AccessType::eAccessPublic,
           /*is_virtual=*/false, /*is_static=*/false,
           /*is_inline=*/false, /*is_explicit=*/false,
@@ -913,7 +913,7 @@ PdbAstBuilder::CreateFunctionDecl(PdbCompilandSymId func_id,
   } else {
     function_decl = m_clang.CreateFunctionDeclaration(
         parent, OptionalClangModuleID(), func_name, func_ct, func_storage,
-        is_inline);
+        is_inline, /*asm_label=*/{});
     CreateFunctionParameters(func_id, *function_decl, param_count);
   }
   return function_decl;

lldb/source/Plugins/SymbolFile/NativePDB/UdtRecordCompleter.cpp

@@ -111,9 +111,8 @@ void UdtRecordCompleter::AddMethod(llvm::StringRef name, TypeIndex type_idx,
   bool is_artificial = (options & MethodOptions::CompilerGenerated) ==
                        MethodOptions::CompilerGenerated;
   m_ast_builder.clang().AddMethodToCXXRecordType(
-      derived_opaque_ty, name.data(), nullptr, method_ct,
-      access_type, attrs.isVirtual(), attrs.isStatic(), false, false, false,
-      is_artificial);
+      derived_opaque_ty, name.data(), /*asm_label=*/{}, method_ct, access_type,
+      attrs.isVirtual(), attrs.isStatic(), false, false, false, is_artificial);
 
   m_cxx_record_map[derived_opaque_ty].insert({name, method_ct});
 }

lldb/source/Plugins/SymbolFile/PDB/PDBASTParser.cpp

@@ -954,7 +954,8 @@ PDBASTParser::GetDeclForSymbol(const llvm::pdb::PDBSymbol &symbol) {
 
     auto decl = m_ast.CreateFunctionDeclaration(
         decl_context, OptionalClangModuleID(), name,
-        type->GetForwardCompilerType(), storage, func->hasInlineAttribute());
+        type->GetForwardCompilerType(), storage, func->hasInlineAttribute(),
+        /*asm_label=*/{});
 
     std::vector<clang::ParmVarDecl *> params;
     if (std::unique_ptr<PDBSymbolTypeFunctionSig> sig = func->getSignature()) {
@@ -1446,7 +1447,7 @@ PDBASTParser::AddRecordMethod(lldb_private::SymbolFile &symbol_file,
   // TODO: get mangled name for the method.
   return m_ast.AddMethodToCXXRecordType(
       record_type.GetOpaqueQualType(), name.c_str(),
-      /*mangled_name*/ nullptr, method_comp_type, access, method.isVirtual(),
+      /*asm_label=*/{}, method_comp_type, access, method.isVirtual(),
       method.isStatic(), method.hasInlineAttribute(),
       /*is_explicit*/ false, // FIXME: Need this field in CodeView.
       /*is_attr_used*/ false,

lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp

@@ -2137,7 +2137,7 @@ std::string TypeSystemClang::GetTypeNameForDecl(const NamedDecl *named_decl,
 FunctionDecl *TypeSystemClang::CreateFunctionDeclaration(
     clang::DeclContext *decl_ctx, OptionalClangModuleID owning_module,
     llvm::StringRef name, const CompilerType &function_clang_type,
-    clang::StorageClass storage, bool is_inline) {
+    clang::StorageClass storage, bool is_inline, llvm::StringRef asm_label) {
   FunctionDecl *func_decl = nullptr;
   ASTContext &ast = getASTContext();
   if (!decl_ctx)
@@ -2158,6 +2158,21 @@ FunctionDecl *TypeSystemClang::CreateFunctionDeclaration(
   func_decl->setConstexprKind(isConstexprSpecified
                                   ? ConstexprSpecKind::Constexpr
                                   : ConstexprSpecKind::Unspecified);
+
+  // Attach an asm(<mangled_name>) label to the FunctionDecl.
+  // This ensures that clang::CodeGen emits function calls
+  // using symbols that are mangled according to the DW_AT_linkage_name.
+  // If we didn't do this, the external symbols wouldn't exactly
+  // match the mangled name LLDB knows about and the IRExecutionUnit
+  // would have to fall back to searching object files for
+  // approximately matching function names. The motivating
+  // example is generating calls to ABI-tagged template functions.
+  // This is done separately for member functions in
+  // AddMethodToCXXRecordType.
+  if (!asm_label.empty())
+    func_decl->addAttr(clang::AsmLabelAttr::CreateImplicit(ast, asm_label,
+                                                           /*literal=*/true));
+
   SetOwningModule(func_decl, owning_module);
   decl_ctx->addDecl(func_decl);
 
@@ -7651,7 +7666,7 @@ TypeSystemClang::CreateParameterDeclarations(
 
 clang::CXXMethodDecl *TypeSystemClang::AddMethodToCXXRecordType(
     lldb::opaque_compiler_type_t type, llvm::StringRef name,
-    const char *mangled_name, const CompilerType &method_clang_type,
+    llvm::StringRef asm_label, const CompilerType &method_clang_type,
     lldb::AccessType access, bool is_virtual, bool is_static, bool is_inline,
     bool is_explicit, bool is_attr_used, bool is_artificial) {
   if (!type || !method_clang_type.IsValid() || name.empty())
@@ -7784,10 +7799,9 @@ clang::CXXMethodDecl *TypeSystemClang::AddMethodToCXXRecordType(
   if (is_attr_used)
     cxx_method_decl->addAttr(clang::UsedAttr::CreateImplicit(getASTContext()));
 
-  if (mangled_name != nullptr) {
+  if (!asm_label.empty())
     cxx_method_decl->addAttr(clang::AsmLabelAttr::CreateImplicit(
-        getASTContext(), mangled_name, /*literal=*/false));
-  }
+        getASTContext(), asm_label, /*literal=*/true));
 
   // Parameters on member function declarations in DWARF generally don't
   // have names, so we omit them when creating the ParmVarDecls.

lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h

@@ -477,7 +477,7 @@ class TypeSystemClang : public TypeSystem {
   clang::FunctionDecl *CreateFunctionDeclaration(
       clang::DeclContext *decl_ctx, OptionalClangModuleID owning_module,
       llvm::StringRef name, const CompilerType &function_Type,
-      clang::StorageClass storage, bool is_inline);
+      clang::StorageClass storage, bool is_inline, llvm::StringRef asm_label);
 
   CompilerType
   CreateFunctionType(const CompilerType &result_type,
@@ -1001,7 +1001,7 @@ class TypeSystemClang : public TypeSystem {
 
   clang::CXXMethodDecl *AddMethodToCXXRecordType(
       lldb::opaque_compiler_type_t type, llvm::StringRef name,
-      const char *mangled_name, const CompilerType &method_type,
+      llvm::StringRef asm_label, const CompilerType &method_type,
       lldb::AccessType access, bool is_virtual, bool is_static, bool is_inline,
       bool is_explicit, bool is_attr_used, bool is_artificial);
 

lldb/unittests/Symbol/TestTypeSystemClang.cpp

@@ -869,7 +869,7 @@ TEST_F(TestTypeSystemClang, TestFunctionTemplateConstruction) {
   CompilerType clang_type = m_ast->CreateFunctionType(int_type, {}, false, 0U);
   FunctionDecl *func = m_ast->CreateFunctionDeclaration(
       TU, OptionalClangModuleID(), "foo", clang_type, StorageClass::SC_None,
-      false);
+      false, /*asm_label=*/{});
   TypeSystemClang::TemplateParameterInfos empty_params;
 
   // Create the actual function template.
@@ -900,7 +900,7 @@ TEST_F(TestTypeSystemClang, TestFunctionTemplateInRecordConstruction) {
   // 2. It is mirroring the behavior of DWARFASTParserClang::ParseSubroutine.
   FunctionDecl *func = m_ast->CreateFunctionDeclaration(
       TU, OptionalClangModuleID(), "foo", clang_type, StorageClass::SC_None,
-      false);
+      false, /*asm_label=*/{});
   TypeSystemClang::TemplateParameterInfos empty_params;
 
   // Create the actual function template.
@@ -938,7 +938,7 @@ TEST_F(TestTypeSystemClang, TestDeletingImplicitCopyCstrDueToMoveCStr) {
   bool is_attr_used = false;
   bool is_artificial = false;
   m_ast->AddMethodToCXXRecordType(
-      t.GetOpaqueQualType(), class_name, nullptr, function_type,
+      t.GetOpaqueQualType(), class_name, /*asm_label=*/{}, function_type,
       lldb::AccessType::eAccessPublic, is_virtual, is_static, is_inline,
       is_explicit, is_attr_used, is_artificial);
 
@@ -975,7 +975,7 @@ TEST_F(TestTypeSystemClang, TestNotDeletingUserCopyCstrDueToMoveCStr) {
     CompilerType function_type = m_ast->CreateFunctionType(
         return_type, args, /*variadic=*/false, /*quals*/ 0U);
     m_ast->AddMethodToCXXRecordType(
-        t.GetOpaqueQualType(), class_name, nullptr, function_type,
+        t.GetOpaqueQualType(), class_name, /*asm_label=*/{}, function_type,
         lldb::AccessType::eAccessPublic, is_virtual, is_static, is_inline,
         is_explicit, is_attr_used, is_artificial);
   }
@@ -987,7 +987,7 @@ TEST_F(TestTypeSystemClang, TestNotDeletingUserCopyCstrDueToMoveCStr) {
         m_ast->CreateFunctionType(return_type, args,
                                   /*variadic=*/false, /*quals*/ 0U);
     m_ast->AddMethodToCXXRecordType(
-        t.GetOpaqueQualType(), class_name, nullptr, function_type,
+        t.GetOpaqueQualType(), class_name, /*asm_label=*/{}, function_type,
         lldb::AccessType::eAccessPublic, is_virtual, is_static, is_inline,
         is_explicit, is_attr_used, is_artificial);
   }
@@ -1098,7 +1098,7 @@ TEST_F(TestTypeSystemClang, AddMethodToCXXRecordType_ParmVarDecls) {
       m_ast->CreateFunctionType(return_type, param_types,
                                 /*variadic=*/false, /*quals*/ 0U);
   m_ast->AddMethodToCXXRecordType(
-      t.GetOpaqueQualType(), "myFunc", nullptr, function_type,
+      t.GetOpaqueQualType(), "myFunc", /*asm_label=*/{}, function_type,
       lldb::AccessType::eAccessPublic, is_virtual, is_static, is_inline,
       is_explicit, is_attr_used, is_artificial);