[LLDB] Simplify task formatter typesystem creation

and add missing nullptr checks. In this case there is no need to
create a new scratch typesystem, we can just reuse the ValueObject's
typesystem.

Author: adrian-prantl

lldb/source/Plugins/Language/Swift/SwiftFormatters.cpp

@@ -798,16 +798,13 @@ class TaskSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
   TaskSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
       : SyntheticChildrenFrontEnd(*valobj_sp.get()) {
     auto target_sp = m_backend.GetTargetSP();
-    auto ts_or_err =
-        target_sp->GetScratchTypeSystemForLanguage(eLanguageTypeSwift);
-    if (auto err = ts_or_err.takeError()) {
-      LLDB_LOG_ERROR(GetLog(LLDBLog::DataFormatters | LLDBLog::Types),
-                     std::move(err),
-                     "could not get Swift type system for Task synthetic "
-                     "provider: {0}");
-      return;
-    }
-    m_ts = llvm::dyn_cast_or_null<TypeSystemSwiftTypeRef>(ts_or_err->get());
+    CompilerType type = valobj_sp->GetCompilerType();
+    m_ts = type.GetTypeSystem().dyn_cast_or_null<TypeSystemSwift>();
+    if (!m_ts)
+      LLDB_LOG(
+          GetLog(LLDBLog::DataFormatters | LLDBLog::Types),
+          "could not get Swift type system for Task synthetic provider: {0}",
+          type.GetMangledTypeName());
   }
 
   constexpr static StringLiteral TaskChildren[] = {
@@ -840,6 +837,8 @@ class TaskSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
   }
 
   lldb::ValueObjectSP GetChildAtIndex(uint32_t idx) override {
+    if (!m_ts)
+      return {};
     auto target_sp = m_backend.GetTargetSP();
 
     // TypeMangling for "Swift.Bool"
@@ -1026,7 +1025,7 @@ class TaskSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
     return {};
   }
 
-  TypeSystemSwiftTypeRef *m_ts = nullptr;
+  TypeSystemSwiftSP m_ts;
   addr_t m_task_ptr = LLDB_INVALID_ADDRESS;
   ReflectionContextInterface::AsyncTaskInfo m_task_info;
   ValueObjectSP m_address_sp;
@@ -1421,25 +1420,21 @@ class ActorSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
     if (!m_is_supported_target)
       return;
 
-    auto target_sp = m_backend.GetTargetSP();
-    auto ts_or_err =
-        target_sp->GetScratchTypeSystemForLanguage(eLanguageTypeSwift);
-    if (auto err = ts_or_err.takeError()) {
-      LLDB_LOG_ERROR(GetLog(LLDBLog::DataFormatters | LLDBLog::Types),
-                     std::move(err),
-                     "could not get Swift type system for Task synthetic "
-                     "provider: {0}");
-      return;
-    }
-    m_ts = llvm::dyn_cast_or_null<TypeSystemSwiftTypeRef>(ts_or_err->get());
+    CompilerType type = valobj_sp->GetCompilerType();
+    m_ts = type.GetTypeSystem().dyn_cast_or_null<TypeSystemSwift>();
+    if (!m_ts)
+      LLDB_LOG(
+          GetLog(LLDBLog::DataFormatters | LLDBLog::Types),
+          "could not get Swift type system for Actor synthetic provider: {0}",
+          type.GetMangledTypeName());
   }
 
   llvm::Expected<uint32_t> CalculateNumChildren() override {
     return m_is_supported_target ? 1 : 0;
   }
 
   lldb::ValueObjectSP GetChildAtIndex(uint32_t idx) override {
-    if (!m_is_supported_target || idx != 0)
+    if (!m_is_supported_target || idx != 0 || !m_ts)
       return {};
 
     if (!m_unprioritised_jobs_sp) {
@@ -1556,7 +1551,7 @@ class ActorSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
 private:
   bool m_is_supported_target = false;
-  TypeSystemSwiftTypeRef *m_ts = nullptr;
+  TypeSystemSwiftSP m_ts;
   std::vector<addr_t> m_job_addrs;
   CompilerType m_task_type;
   ValueObjectSP m_unprioritised_jobs_sp;