[lldb] Remove assumption from Clang-based data formatters that their types are in...
authorRaphael Isemann <teemperor@gmail.com>
Thu, 10 Dec 2020 14:38:21 +0000 (15:38 +0100)
committerRaphael Isemann <teemperor@gmail.com>
Thu, 10 Dec 2020 16:35:03 +0000 (17:35 +0100)
Several data formatters assume their types are in the Target's scratch AST and
build new types from that scratch AST instance. However, types from different
ASTs shouldn't be mixed, so this (unchecked) assumption may lead to problems if
we ever have more than one scratch AST or someone somehow invokes data
formatters on a type that are not in the scratch AST.

Instead we can use in all the formatters just the TypeSystem of the type we're
formatting. That's much simpler and avoids all the headache of finding the right
TypeSystem that matches the one of the formatted type.

Right now LLDB only has one scratch TypeSystemClang instance and we format only
types that are in the scratch AST, so this doesn't change anything in the
current way LLDB works. The intention here is to allow follow up refactorings
that introduce multiple scratch ASTs with the same Target.

Differential Revision: https://reviews.llvm.org/D92757

lldb/source/DataFormatters/VectorType.cpp
lldb/source/Plugins/Language/CPlusPlus/BlockPointer.cpp
lldb/source/Plugins/Language/ObjC/CoreMedia.cpp

index fd1c0bc..cc24bb1 100644 (file)
@@ -220,20 +220,8 @@ public:
     CompilerType parent_type(m_backend.GetCompilerType());
     CompilerType element_type;
     parent_type.IsVectorType(&element_type, nullptr);
-    TypeSystem *type_system = nullptr;
-    if (auto target_sp = m_backend.GetTargetSP()) {
-      auto type_system_or_err =
-          target_sp->GetScratchTypeSystemForLanguage(lldb::eLanguageTypeC);
-      if (auto err = type_system_or_err.takeError()) {
-        LLDB_LOG_ERROR(
-            lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DATAFORMATTERS),
-            std::move(err), "Unable to update from scratch TypeSystem");
-      } else {
-        type_system = &type_system_or_err.get();
-      }
-    }
-    m_child_type =
-        ::GetCompilerTypeForFormat(m_parent_format, element_type, type_system);
+    m_child_type = ::GetCompilerTypeForFormat(m_parent_format, element_type,
+                                              parent_type.GetTypeSystem());
     m_num_children = ::CalculateNumChildren(parent_type, m_child_type);
     m_item_format = GetItemFormatForFormat(m_parent_format, m_child_type);
     return false;
index 42f6bd9..35788a6 100644 (file)
@@ -50,11 +50,7 @@ public:
     }
 
     TypeSystemClang *clang_ast_context =
-        llvm::dyn_cast<TypeSystemClang>(&type_system_or_err.get());
-
-    if (!clang_ast_context) {
-      return;
-    }
+        llvm::cast<TypeSystemClang>(block_pointer_type.GetTypeSystem());
 
     std::shared_ptr<ClangASTImporter> clang_ast_importer;
     auto *state = target_sp->GetPersistentExpressionStateForLanguage(
index ac2f45b..efc80cc 100644 (file)
@@ -25,21 +25,12 @@ bool lldb_private::formatters::CMTimeSummaryProvider(
   if (!type.IsValid())
     return false;
 
-  auto type_system_or_err =
-      valobj.GetExecutionContextRef()
-          .GetTargetSP()
-          ->GetScratchTypeSystemForLanguage(lldb::eLanguageTypeC);
-  if (auto err = type_system_or_err.takeError()) {
-    LLDB_LOG_ERROR(
-        lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DATAFORMATTERS),
-        std::move(err), "Failed to get scratch type system");
-    return false;
-  }
+  TypeSystem *type_system = type.GetTypeSystem();
   // fetch children by offset to compensate for potential lack of debug info
-  auto int64_ty = type_system_or_err->GetBuiltinTypeForEncodingAndBitSize(
-      eEncodingSint, 64);
-  auto int32_ty = type_system_or_err->GetBuiltinTypeForEncodingAndBitSize(
-      eEncodingSint, 32);
+  auto int64_ty =
+      type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingSint, 64);
+  auto int32_ty =
+      type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingSint, 32);
 
   auto value_sp(valobj.GetSyntheticChildAtOffset(0, int64_ty, true));
   auto timescale_sp(valobj.GetSyntheticChildAtOffset(8, int32_ty, true));