NSAutoreleasePool instance should be added to all threads.

docs/workflow/trimming/feature-switches.md

@@ -17,7 +17,7 @@ configurations but their defaults might vary as any SDK can set the defaults dif
 | HttpActivityPropagationSupport | System.Net.Http.EnableActivityPropagation | Any dependency related to diagnostics support for System.Net.Http is trimmed when set to false |
 | HttpNativeHandler | System.Net.Http.UseNativeHttpHandler | HttpClient uses by default platform native implementation of HttpMessageHandler if set to true. |
 | StartupHookSupport | System.StartupHookProvider.IsSupported | Startup hooks are disabled when set to false. Startup hook related functionality can be trimmed. |
-| TBD | System.Threading.ThreadPool.EnableDispatchAutoreleasePool | When set to true, creates an NSAutoreleasePool around each thread pool work item on applicable platforms. |
+| TBD | System.Threading.Thread.EnableAutoreleasePool | When set to true, creates an NSAutoreleasePool for each thread and thread pool work item on applicable platforms. |
 | CustomResourceTypesSupport | System.Resources.ResourceManager.AllowCustomResourceTypes | Use of custom resource types is disabled when set to false. ResourceManager code paths that use reflection for custom types can be trimmed. |
 | EnableUnsafeBinaryFormatterInDesigntimeLicenseContextSerialization | System.ComponentModel.TypeConverter.EnableUnsafeBinaryFormatterInDesigntimeLicenseContextSerialization | BinaryFormatter serialization support is trimmed when set to false. |
 

src/coreclr/vm/ceemain.cpp

@@ -633,6 +633,7 @@ void EEStartupHelper()
     static ConfigDWORD breakOnEELoad;
     EX_TRY
     {
+        Thread* mainThread = NULL;
         g_fEEInit = true;
 
 #ifndef CROSSGEN_COMPILE
@@ -917,13 +918,13 @@ void EEStartupHelper()
         }
 
         // throws on error
-        SetupThread();
+        mainThread = SetupMainThread();
 
 #ifdef DEBUGGING_SUPPORTED
         // Notify debugger once the first thread is created to finish initialization.
         if (g_pDebugInterface != NULL)
         {
-            g_pDebugInterface->StartupPhase2(GetThread());
+            g_pDebugInterface->StartupPhase2(mainThread);
         }
 #endif
 
@@ -1030,7 +1031,10 @@ void EEStartupHelper()
                                                 g_MiniMetaDataBuffMaxSize, MEM_COMMIT, PAGE_READWRITE);
 #endif // FEATURE_MINIMETADATA_IN_TRIAGEDUMPS
 
-#endif // CROSSGEN_COMPILE
+        // Initialize the platform specific context.
+        mainThread->InitPlatformContext();
+
+#endif // !CROSSGEN_COMPILE
 
         g_fEEStarted = TRUE;
         g_EEStartupStatus = S_OK;
@@ -1056,7 +1060,6 @@ void EEStartupHelper()
 
         // Perform CoreLib consistency check if requested
         g_CoreLib.CheckExtended();
-
 #endif // _DEBUG
 
 #endif // !CROSSGEN_COMPILE

src/coreclr/vm/corelib.h

@@ -881,6 +881,9 @@ DEFINE_FIELD_U(_priority,                 ThreadBaseObject,   m_Priority)
 DEFINE_CLASS(THREAD,                Threading,              Thread)
 DEFINE_METHOD(THREAD,               INTERNAL_GET_CURRENT_THREAD,             InternalGetCurrentThread,                    SM_RetIntPtr)
 DEFINE_METHOD(THREAD,               START_CALLBACK,                          StartCallback,                               IM_RetVoid)
+#if defined(TARGET_OSX) || defined(TARGET_MACCATALYST) || defined(TARGET_IOS) || defined(TARGET_TVOS)
+DEFINE_METHOD(THREAD,               ALLOCATETHREADLOCALAUTORELEASEPOOL,      AllocateThreadlocalAutoreleasePool,          SM_RetVoid)
+#endif // defined(TARGET_OSX) || defined(TARGET_MACCATALYST) || defined(TARGET_IOS) || defined(TARGET_TVOS)
 
 DEFINE_CLASS(IOCB_HELPER,              Threading,            _IOCompletionCallback)
 DEFINE_METHOD(IOCB_HELPER,             PERFORM_IOCOMPLETION_CALLBACK,        PerformIOCompletionCallback,          SM_UInt_UInt_PtrNativeOverlapped_RetVoid)

src/coreclr/vm/finalizerthread.cpp

@@ -222,6 +222,7 @@ void FinalizerThread::WaitForFinalizerEvent (CLREvent *event)
 }
 
 static BOOL s_FinalizerThreadOK = FALSE;
+static BOOL s_InitializedFinalizerThreadForPlatform = FALSE;
 
 VOID FinalizerThread::FinalizerThreadWorker(void *args)
 {
@@ -289,6 +290,15 @@ VOID FinalizerThread::FinalizerThreadWorker(void *args)
                 bPriorityBoosted = TRUE;
         }
 
+        // The Finalizer thread is started very early in EE startup. We defered
+        // initialization until a point we are sure the EE is up and running. At
+        // this point we make a single attempt and if it fails won't try again.
+        if (!s_InitializedFinalizerThreadForPlatform)
+        {
+            s_InitializedFinalizerThreadForPlatform = TRUE;
+            GetFinalizerThread()->InitPlatformContext();
+        }
+
         JitHost::Reclaim();
 
         GetFinalizerThread()->DisablePreemptiveGC();

src/coreclr/vm/gcenv.ee.cpp

@@ -1382,7 +1382,7 @@ namespace
             ClrFlsSetThreadType(ThreadType_GC);
             args->Thread->SetGCSpecial(true);
             STRESS_LOG_RESERVE_MEM(GC_STRESSLOG_MULTIPLY);
-            args->HasStarted = !!args->Thread->HasStarted(false);
+            args->HasStarted = !!args->Thread->HasStarted();
 
             Thread* thread = args->Thread;
             auto threadStart = args->ThreadStart;
@@ -1407,7 +1407,7 @@ namespace
             return false;
         }
 
-        args.Thread->SetBackground(TRUE, FALSE);
+        args.Thread->SetBackground(TRUE);
         args.Thread->StartThread();
 
         // Wait for the thread to be in its main loop