Share ObjectiveCMarshal reference-tracking logic between CoreCLR and NativeAOT

src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeHelpers.CoreCLR.cs

@@ -844,6 +844,9 @@ internal unsafe struct MethodTable
 #if FEATURE_TYPEEQUIVALENCE
  private const uint enum_flag_HasTypeEquivalence = 0x02000000;
 #endif // FEATURE_TYPEEQUIVALENCE
+#if FEATURE_OBJCMARSHAL
+ private const uint enum_flag_IsTrackedReferenceWithFinalizer = 0x04000000;
+#endif // FEATURE_OBJCMARSHAL
  private const uint enum_flag_HasFinalizer = 0x00100000;
  private const uint enum_flag_Collectible = 0x00200000;
  private const uint enum_flag_Category_Mask = 0x000F0000;
@@ -904,6 +907,10 @@ internal unsafe struct MethodTable
  public bool HasTypeEquivalence => (Flags & enum_flag_HasTypeEquivalence) != 0;
 #endif // FEATURE_TYPEEQUIVALENCE
 
+#if FEATURE_OBJCMARSHAL
+ public bool IsTrackedReferenceWithFinalizer => (Flags & enum_flag_IsTrackedReferenceWithFinalizer) != 0;
+#endif // FEATURE_OBJCMARSHAL
+
  public bool HasFinalizer => (Flags & enum_flag_HasFinalizer) != 0;
 
  public bool IsCollectible => (Flags & enum_flag_Collectible) != 0;

src/coreclr/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.CoreCLR.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Diagnostics;
 using System.Runtime.CompilerServices;
 using System.Runtime.Versioning;
 
@@ -31,19 +32,35 @@ private static partial bool TrySetGlobalMessageSendCallback(
  private static unsafe partial bool TryInitializeReferenceTracker(
  delegate* unmanaged<void> beginEndCallback,
  delegate* unmanaged<IntPtr, int> isReferencedCallback,
- delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization);
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization,
+ ObjectHandleOnStack objectTrackingInfoTable);
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_CreateReferenceTrackingHandle")]
- private static partial IntPtr CreateReferenceTrackingHandleInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static bool TryInitializeReferenceTracker(
+ delegate* unmanaged<void> beginEndCallback,
+ delegate* unmanaged<IntPtr, int> isReferencedCallback,
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization)
+ {
+ // Make a local of the readonly field because it needs to be passed by ref to a QCall
+ // and it is marked as readonly to prevent accidental reassignment.
+ ConditionalWeakTable<object, ObjcTrackingInformation> objects = s_objects;
+ bool result = TryInitializeReferenceTracker(
+ beginEndCallback,
+ isReferencedCallback,
+ trackedObjectEnteredFinalization,
+ ObjectHandleOnStack.Create(ref objects));
+ Debug.Assert(object.ReferenceEquals(objects, s_objects));
+
+ return result;
+ }
+
+ [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_AllocateReferenceTrackingHandle")]
+ private static partial IntPtr AllocateReferenceTrackingHandle(ObjectHandleOnStack obj);
+
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => AllocateReferenceTrackingHandle(ObjectHandleOnStack.Create(ref obj));
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_GetOrCreateReferenceTrackingMemory")]
- private static partial void GetOrCreateReferenceTrackingMemoryInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static unsafe bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
 
  [UnmanagedCallersOnly]
  internal static unsafe void* InvokeUnhandledExceptionPropagation(Exception* pExceptionArg, IntPtr methodDesc, IntPtr* pContext, Exception* pException)

src/coreclr/debug/daccess/request.cpp

@@ -23,6 +23,10 @@
 #include <interoplibabi.h>
 #endif // FEATURE_COMWRAPPERS
 
+#if defined(FEATURE_OBJCMARSHAL)
+#include <interoplibinterface.h>
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 // It is unfortunate having to include this header just to get the definition of GenericModeBlock
 #include <msodw.h>
@@ -2351,7 +2355,7 @@ ClrDataAccess::GetObjectData(CLRDATA_ADDRESS addr, struct DacpObjectData *object
  objectData->ElementTypeHandle = (CLRDATA_ADDRESS)(thElem.AsTAddr());
  objectData->dwRank = mt->GetRank();
  objectData->dwNumComponents = pArrayObj->GetNumComponents ();
- objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetDataPtr (TRUE));
+ objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetGCSafeDataPtr());
  objectData->ArrayBoundsPtr = HOST_CDADDR(pArrayObj->GetBoundsPtr());
  objectData->ArrayLowerBoundsPtr = HOST_CDADDR(pArrayObj->GetLowerBoundsPtr());
  }
@@ -5393,21 +5397,26 @@ namespace
 #ifdef FEATURE_OBJCMARSHAL
  EX_TRY_ALLOW_DATATARGET_MISSING_MEMORY
  {
- PTR_SyncBlock pSyncBlk = DACGetSyncBlockFromObjectPointer(CLRDATA_ADDRESS_TO_TADDR(objAddr), target);
- if (pSyncBlk != NULL)
+ if (g_ObjectiveCTrackingInfoTable != NULL)
  {
-PTR_InteropSyncBlockInfo pInfo = pSyncBlk->GetInteropInfoNoCreate();
- if (pInfo != NULL)
+CONDITIONAL_WEAK_TABLE_REF trackingTable = (CONDITIONAL_WEAK_TABLE_REF)ObjectFromHandle(g_ObjectiveCTrackingInfoTable);
+ if (trackingTable != NULL)
  {
- CLRDATA_ADDRESS taggedMemoryLocal = PTR_CDADDR(pInfo->GetTaggedMemory());
- if (taggedMemoryLocal != NULL)
+ OBJECTREF object = OBJECTREF(CLRDATA_ADDRESS_TO_TADDR(objAddr));
+ OBJC_TRACKING_INFO_REF trackingInfo = NULL;
+ if (trackingTable->TryGetValue(object, &trackingInfo) && trackingInfo != NULL)
  {
- hasTaggedMemory = TRUE;
- if (taggedMemory)
- *taggedMemory = taggedMemoryLocal;
+ TADDR memory = (TADDR)trackingInfo->_memory;
+ if (memory != NULL)
+ {
+ hasTaggedMemory = TRUE;
+ if (taggedMemory)
+ *taggedMemory = (CLRDATA_ADDRESS)memory;
 
- if (taggedMemorySizeInBytes)
- *taggedMemorySizeInBytes = pInfo->GetTaggedMemorySizeInBytes();
+ constexpr int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ if (taggedMemorySizeInBytes)
+ *taggedMemorySizeInBytes = TAGGED_MEMORY_SIZE_IN_POINTERS * sizeof(TADDR);
+ }
  }
  }
  }

src/coreclr/inc/dacvars.h

@@ -214,6 +214,10 @@ DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_pRCWCleanupList, ::g_pRCWCleanupList)
 DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_knownQueryInterfaceImplementations, InteropLib::ABI::g_knownQueryInterfaceImplementations)
 #endif // FEATURE_COMWRAPPERS
 
+#ifdef FEATURE_OBJCMARSHAL
+DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_ObjectiveCTrackingInfoTable, ::g_ObjectiveCTrackingInfoTable)
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeLoadedBaseAddress, ::g_runtimeLoadedBaseAddress)
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeVirtualSize, ::g_runtimeVirtualSize)

src/coreclr/nativeaot/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.NativeAot.cs

@@ -11,8 +11,6 @@ namespace System.Runtime.InteropServices.ObjectiveC
  public static unsafe partial class ObjectiveCMarshal
  {
  private static readonly IntPtr[] s_ObjcMessageSendFunctions = new IntPtr[(int)MessageSendFunction.MsgSendSuperStret + 1];
- private static bool s_initialized;
- private static readonly ConditionalWeakTable<object, ObjcTrackingInformation> s_objects = new();
  private static delegate* unmanaged[SuppressGCTransition]<void*, int> s_IsTrackedReferenceCallback;
  private static delegate* unmanaged[SuppressGCTransition]<void*, void> s_OnEnteredFinalizerQueueCallback;
 
@@ -116,94 +114,13 @@ private static bool TryInitializeReferenceTracker(
 
  s_IsTrackedReferenceCallback = (delegate* unmanaged[SuppressGCTransition]<void*, int>)isReferencedCallback;
  s_OnEnteredFinalizerQueueCallback = (delegate* unmanaged[SuppressGCTransition]<void*, void>)trackedObjectEnteredFinalization;
- s_initialized = true;
-
  return true;
  }
 
- private static IntPtr CreateReferenceTrackingHandleInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- // Rely on GetOrCreateReferenceTrackingMemoryInternal for state checking.
- GetOrCreateReferenceTrackingMemoryInternal(obj, out memInSizeT, out mem);
- return RuntimeImports.RhHandleAllocRefCounted(obj);
- }
-
- private static void GetOrCreateReferenceTrackingMemoryInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- if (!s_initialized)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCMarshalNotInitialized);
- }
-
- if (!obj.GetMethodTable()->IsTrackedReferenceWithFinalizer)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCTypeNoFinalizer);
- }
-
- var trackerInfo = s_objects.GetOrAdd(obj, static o => new ObjcTrackingInformation());
- trackerInfo.EnsureInitialized(obj);
- trackerInfo.GetTaggedMemory(out memInSizeT, out mem);
- }
-
- internal class ObjcTrackingInformation
- {
- // This matches the CoreCLR implementation. See
- // InteropSyncBlockInfo::m_taggedAlloc in syncblk.h .
- private const int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => RuntimeImports.RhHandleAllocRefCounted(obj);
 
- internal IntPtr _memory;
- private IntPtr _longWeakHandle;
-
- public ObjcTrackingInformation()
- {
- _memory = (IntPtr)NativeMemory.AllocZeroed(TAGGED_MEMORY_SIZE_IN_POINTERS * (nuint)IntPtr.Size);
- }
-
- public void GetTaggedMemory(out int memInSizeT, out IntPtr mem)
- {
- memInSizeT = TAGGED_MEMORY_SIZE_IN_POINTERS;
- mem = _memory;
- }
-
- public void EnsureInitialized(object o)
- {
- if (_longWeakHandle != IntPtr.Zero)
- {
- return;
- }
-
- IntPtr newHandle = RuntimeImports.RhHandleAlloc(o, GCHandleType.WeakTrackResurrection);
- if (Interlocked.CompareExchange(ref _longWeakHandle, newHandle, IntPtr.Zero) != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(newHandle);
- }
- }
-
- ~ObjcTrackingInformation()
- {
- if (_longWeakHandle != IntPtr.Zero && RuntimeImports.RhHandleGet(_longWeakHandle) != null)
- {
- GC.ReRegisterForFinalize(this);
- return;
- }
-
- if (_memory != IntPtr.Zero)
- {
- NativeMemory.Free((void*)_memory);
- _memory = IntPtr.Zero;
- }
- if (_longWeakHandle != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(_longWeakHandle);
- _longWeakHandle = IntPtr.Zero;
- }
- }
- }
+ private static bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
  }
 }

src/coreclr/vm/CMakeLists.txt

@@ -59,6 +59,7 @@ set(VM_SOURCES_DAC_AND_WKS_COMMON
  clsload.cpp
  codeman.cpp
  codeversion.cpp
+ conditionalweaktable.cpp
  contractimpl.cpp
  corhost.cpp
  crst.cpp
@@ -277,7 +278,6 @@ list(APPEND VM_HEADERS_DAC_AND_WKS_COMMON
 
 set(VM_SOURCES_DAC
  ${VM_SOURCES_DAC_AND_WKS_COMMON}
- conditionalweaktable.cpp # The usage of conditionalweaktable is only in the DAC, but we put the headers in the VM to enable validation.
 )
 
 set(VM_HEADERS_DAC

src/coreclr/vm/binder.cpp

@@ -21,7 +21,7 @@
 #include "sigbuilder.h"
 #include "configuration.h"
 #include "conditionalweaktable.h"
-#include "interoplibinterface_comwrappers.h"
+#include "interoplibinterface.h"
 #include "assemblynative.hpp"
 
 //

src/coreclr/vm/conditionalweaktable.cpp

@@ -4,11 +4,20 @@
 
 #include "conditionalweaktable.h"
 #include "gchandleutilities.h"
+
+#ifdef DACCESS_COMPILE
 #include "../debug/daccess/gcinterface.dac.h"
+#endif // DACCESS_COMPILE
 
 bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF* value)
 {
- STANDARD_VM_CONTRACT;
+ CONTRACTL
+ {
+ NOTHROW;
+ GC_NOTRIGGER;
+ MODE_ANY;
+ }
+ CONTRACTL_END;
  SUPPORTS_DAC;
  _ASSERTE(key != nullptr && value != nullptr);
 
@@ -24,11 +33,19 @@ bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF*
  int bucket = hashCode & (_buckets->GetNumComponents() - 1);
  PTR_int32_t buckets = _buckets->GetDirectPointerToNonObjectElements();
  DPTR(Entry) entries = _entries->GetDirectPointerToNonObjectElements();
+
  for (int entriesIndex = buckets[bucket]; entriesIndex != -1; entriesIndex = entries[entriesIndex].Next)
  {
- if (entries[entriesIndex].HashCode == hashCode && ObjectFromHandle(entries[entriesIndex].depHnd) == key)
+ const Entry& entry = entries[entriesIndex];
+ if (entry.HashCode == hashCode && ObjectFromHandle(entry.depHnd) == key)
  {
- *value = HndGetHandleExtraInfo(entries[entriesIndex].depHnd);
+#ifdef DACCESS_COMPILE
+ // In the DACCESS_COMPILE, the handle helper is directly accessible.
+ *value = GetDependentHandleSecondary(entry.depHnd);
+#else
+ IGCHandleManager* mgr = GCHandleUtilities::GetGCHandleManager();
+ *value = ObjectToOBJECTREF(mgr->GetDependentHandleSecondary(entry.depHnd));
+#endif // !DACCESS_COMPILE
  return true;
  }
  }

src/coreclr/vm/conditionalweaktable.h

@@ -39,22 +39,20 @@ class ConditionalWeakTableContainerObject final : public Object
  ENTRYARRAYREF _entries;
 
 public:
-#ifdef DACCESS_COMPILE
  bool TryGetValue(OBJECTREF key, OBJECTREF* value);
-#endif
 };
 
 class ConditionalWeakTableObject final : public Object
 {
  friend class CoreLibBinder;
  OBJECTREF _lock;
- VolatilePtr<ConditionalWeakTableContainerObject, CONDITIONAL_WEAK_TABLE_CONTAINER_REF> _container;
+ VolatilePtr<ConditionalWeakTableContainerObject> _container;
 public:
-#ifdef DACCESS_COMPILE
- // Currently, we only use this for access from the DAC, so we don't need to worry about
- // locking or tracking the active enumerator count.
- // If we need to use this in a context where the runtime isn't suspended, we need to add
- // the locking and tracking support.
+ // This helper can be used when the runtime is suspended (for example, DAC access
+ // or Objective-C interop callbacks that run under GC suspension). During suspension
+ // the table shape is stable since no mutations can run, so lock-free lookup is safe.
+ // If we need to use this in a context where the runtime isn't suspended, we need to
+ // add locking and active enumerator tracking support.
  template<typename TKey, typename TValue>
  bool TryGetValue(TKey key, TValue* value)
  {
@@ -67,10 +65,8 @@ class ConditionalWeakTableObject final : public Object
  {
  *value = (TValue)valueObj;
  }
-
  return found;
  }
-#endif
 };
 
 #endif // CONDITIONAL_WEAK_TABLE_H

src/coreclr/vm/corelib.h

@@ -460,6 +460,9 @@ DEFINE_FIELD_U(_buckets, GCHandleSetObject, _buckets)
 #ifdef FEATURE_OBJCMARSHAL
 DEFINE_CLASS(OBJCMARSHAL, ObjectiveC, ObjectiveCMarshal)
 DEFINE_METHOD(OBJCMARSHAL, INVOKEUNHANDLEDEXCEPTIONPROPAGATION, InvokeUnhandledExceptionPropagation, SM_PtrException_IntPtr_PtrIntPtr_PtrException_RetVoidPtr)
+DEFINE_FIELD(OBJCMARSHAL, OBJECTS, s_objects)
+DEFINE_CLASS_U(ObjectiveC, ObjectiveCMarshal+ObjcTrackingInformation, ObjcTrackingInformationObject)
+DEFINE_FIELD_U(_memory, ObjcTrackingInformationObject, _memory)
 #endif // FEATURE_OBJCMARSHAL
 
 DEFINE_CLASS_U(Interop, TypeMapLazyDictionary+CallbackContext, CallbackContext)

src/coreclr/vm/datadescriptor/datadescriptor.inc

@@ -220,9 +220,6 @@ CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCW, cdac_data<InteropSyncBlock
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, RCW, cdac_data<InteropSyncBlockInfo>::RCW)
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCF, cdac_data<InteropSyncBlockInfo>::CCF)
 #endif // FEATURE_COMINTEROP
-#ifdef FEATURE_OBJCMARSHAL
-CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, TaggedMemory, cdac_data<InteropSyncBlockInfo>::TaggedMemory)
-#endif // FEATURE_OBJCMARSHAL
 CDAC_TYPE_END(InteropSyncBlockInfo)
 
 CDAC_TYPE_BEGIN(SyncBlock)

src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeHelpers.CoreCLR.cs

@@ -844,6 +844,9 @@ internal unsafe struct MethodTable
 #if FEATURE_TYPEEQUIVALENCE
  private const uint enum_flag_HasTypeEquivalence = 0x02000000;
 #endif // FEATURE_TYPEEQUIVALENCE
+#if FEATURE_OBJCMARSHAL
+ private const uint enum_flag_IsTrackedReferenceWithFinalizer = 0x04000000;
+#endif // FEATURE_OBJCMARSHAL
  private const uint enum_flag_HasFinalizer = 0x00100000;
  private const uint enum_flag_Collectible = 0x00200000;
  private const uint enum_flag_Category_Mask = 0x000F0000;
@@ -904,6 +907,10 @@ internal unsafe struct MethodTable
  public bool HasTypeEquivalence => (Flags & enum_flag_HasTypeEquivalence) != 0;
 #endif // FEATURE_TYPEEQUIVALENCE
 
+#if FEATURE_OBJCMARSHAL
+ public bool IsTrackedReferenceWithFinalizer => (Flags & enum_flag_IsTrackedReferenceWithFinalizer) != 0;
+#endif // FEATURE_OBJCMARSHAL
+
  public bool HasFinalizer => (Flags & enum_flag_HasFinalizer) != 0;
 
  public bool IsCollectible => (Flags & enum_flag_Collectible) != 0;

src/coreclr/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.CoreCLR.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Diagnostics;
 using System.Runtime.CompilerServices;
 using System.Runtime.Versioning;
 
@@ -31,19 +32,35 @@ private static partial bool TrySetGlobalMessageSendCallback(
  private static unsafe partial bool TryInitializeReferenceTracker(
  delegate* unmanaged<void> beginEndCallback,
  delegate* unmanaged<IntPtr, int> isReferencedCallback,
- delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization);
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization,
+ ObjectHandleOnStack objectTrackingInfoTable);
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_CreateReferenceTrackingHandle")]
- private static partial IntPtr CreateReferenceTrackingHandleInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static bool TryInitializeReferenceTracker(
+ delegate* unmanaged<void> beginEndCallback,
+ delegate* unmanaged<IntPtr, int> isReferencedCallback,
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization)
+ {
+ // Make a local of the readonly field because it needs to be passed by ref to a QCall
+ // and it is marked as readonly to prevent accidental reassignment.
+ ConditionalWeakTable<object, ObjcTrackingInformation> objects = s_objects;
+ bool result = TryInitializeReferenceTracker(
+ beginEndCallback,
+ isReferencedCallback,
+ trackedObjectEnteredFinalization,
+ ObjectHandleOnStack.Create(ref objects));
+ Debug.Assert(object.ReferenceEquals(objects, s_objects));
+
+ return result;
+ }
+
+ [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_AllocateReferenceTrackingHandle")]
+ private static partial IntPtr AllocateReferenceTrackingHandle(ObjectHandleOnStack obj);
+
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => AllocateReferenceTrackingHandle(ObjectHandleOnStack.Create(ref obj));
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_GetOrCreateReferenceTrackingMemory")]
- private static partial void GetOrCreateReferenceTrackingMemoryInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static unsafe bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
 
  [UnmanagedCallersOnly]
  internal static unsafe void* InvokeUnhandledExceptionPropagation(Exception* pExceptionArg, IntPtr methodDesc, IntPtr* pContext, Exception* pException)

src/coreclr/debug/daccess/request.cpp

@@ -23,6 +23,10 @@
 #include <interoplibabi.h>
 #endif // FEATURE_COMWRAPPERS
 
+#if defined(FEATURE_OBJCMARSHAL)
+#include <interoplibinterface.h>
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 // It is unfortunate having to include this header just to get the definition of GenericModeBlock
 #include <msodw.h>
@@ -2351,7 +2355,7 @@ ClrDataAccess::GetObjectData(CLRDATA_ADDRESS addr, struct DacpObjectData *object
  objectData->ElementTypeHandle = (CLRDATA_ADDRESS)(thElem.AsTAddr());
  objectData->dwRank = mt->GetRank();
  objectData->dwNumComponents = pArrayObj->GetNumComponents ();
- objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetDataPtr (TRUE));
+ objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetGCSafeDataPtr());
  objectData->ArrayBoundsPtr = HOST_CDADDR(pArrayObj->GetBoundsPtr());
  objectData->ArrayLowerBoundsPtr = HOST_CDADDR(pArrayObj->GetLowerBoundsPtr());
  }
@@ -5393,21 +5397,26 @@ namespace
 #ifdef FEATURE_OBJCMARSHAL
  EX_TRY_ALLOW_DATATARGET_MISSING_MEMORY
  {
- PTR_SyncBlock pSyncBlk = DACGetSyncBlockFromObjectPointer(CLRDATA_ADDRESS_TO_TADDR(objAddr), target);
- if (pSyncBlk != NULL)
+ if (g_ObjectiveCTrackingInfoTable != NULL)
  {
-PTR_InteropSyncBlockInfo pInfo = pSyncBlk->GetInteropInfoNoCreate();
- if (pInfo != NULL)
+CONDITIONAL_WEAK_TABLE_REF trackingTable = (CONDITIONAL_WEAK_TABLE_REF)ObjectFromHandle(g_ObjectiveCTrackingInfoTable);
+ if (trackingTable != NULL)
  {
- CLRDATA_ADDRESS taggedMemoryLocal = PTR_CDADDR(pInfo->GetTaggedMemory());
- if (taggedMemoryLocal != NULL)
+ OBJECTREF object = OBJECTREF(CLRDATA_ADDRESS_TO_TADDR(objAddr));
+ OBJC_TRACKING_INFO_REF trackingInfo = NULL;
+ if (trackingTable->TryGetValue(object, &trackingInfo) && trackingInfo != NULL)
  {
- hasTaggedMemory = TRUE;
- if (taggedMemory)
- *taggedMemory = taggedMemoryLocal;
+ TADDR memory = (TADDR)trackingInfo->_memory;
+ if (memory != NULL)
+ {
+ hasTaggedMemory = TRUE;
+ if (taggedMemory)
+ *taggedMemory = (CLRDATA_ADDRESS)memory;
 
- if (taggedMemorySizeInBytes)
- *taggedMemorySizeInBytes = pInfo->GetTaggedMemorySizeInBytes();
+ constexpr int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ if (taggedMemorySizeInBytes)
+ *taggedMemorySizeInBytes = TAGGED_MEMORY_SIZE_IN_POINTERS * sizeof(TADDR);
+ }
  }
  }
  }

src/coreclr/inc/dacvars.h

@@ -214,6 +214,10 @@ DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_pRCWCleanupList, ::g_pRCWCleanupList)
 DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_knownQueryInterfaceImplementations, InteropLib::ABI::g_knownQueryInterfaceImplementations)
 #endif // FEATURE_COMWRAPPERS
 
+#ifdef FEATURE_OBJCMARSHAL
+DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_ObjectiveCTrackingInfoTable, ::g_ObjectiveCTrackingInfoTable)
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeLoadedBaseAddress, ::g_runtimeLoadedBaseAddress)
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeVirtualSize, ::g_runtimeVirtualSize)

src/coreclr/nativeaot/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.NativeAot.cs

@@ -11,8 +11,6 @@ namespace System.Runtime.InteropServices.ObjectiveC
  public static unsafe partial class ObjectiveCMarshal
  {
  private static readonly IntPtr[] s_ObjcMessageSendFunctions = new IntPtr[(int)MessageSendFunction.MsgSendSuperStret + 1];
- private static bool s_initialized;
- private static readonly ConditionalWeakTable<object, ObjcTrackingInformation> s_objects = new();
  private static delegate* unmanaged[SuppressGCTransition]<void*, int> s_IsTrackedReferenceCallback;
  private static delegate* unmanaged[SuppressGCTransition]<void*, void> s_OnEnteredFinalizerQueueCallback;
 
@@ -116,94 +114,13 @@ private static bool TryInitializeReferenceTracker(
 
  s_IsTrackedReferenceCallback = (delegate* unmanaged[SuppressGCTransition]<void*, int>)isReferencedCallback;
  s_OnEnteredFinalizerQueueCallback = (delegate* unmanaged[SuppressGCTransition]<void*, void>)trackedObjectEnteredFinalization;
- s_initialized = true;
-
  return true;
  }
 
- private static IntPtr CreateReferenceTrackingHandleInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- // Rely on GetOrCreateReferenceTrackingMemoryInternal for state checking.
- GetOrCreateReferenceTrackingMemoryInternal(obj, out memInSizeT, out mem);
- return RuntimeImports.RhHandleAllocRefCounted(obj);
- }
-
- private static void GetOrCreateReferenceTrackingMemoryInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- if (!s_initialized)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCMarshalNotInitialized);
- }
-
- if (!obj.GetMethodTable()->IsTrackedReferenceWithFinalizer)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCTypeNoFinalizer);
- }
-
- var trackerInfo = s_objects.GetOrAdd(obj, static o => new ObjcTrackingInformation());
- trackerInfo.EnsureInitialized(obj);
- trackerInfo.GetTaggedMemory(out memInSizeT, out mem);
- }
-
- internal class ObjcTrackingInformation
- {
- // This matches the CoreCLR implementation. See
- // InteropSyncBlockInfo::m_taggedAlloc in syncblk.h .
- private const int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => RuntimeImports.RhHandleAllocRefCounted(obj);
 
- internal IntPtr _memory;
- private IntPtr _longWeakHandle;
-
- public ObjcTrackingInformation()
- {
- _memory = (IntPtr)NativeMemory.AllocZeroed(TAGGED_MEMORY_SIZE_IN_POINTERS * (nuint)IntPtr.Size);
- }
-
- public void GetTaggedMemory(out int memInSizeT, out IntPtr mem)
- {
- memInSizeT = TAGGED_MEMORY_SIZE_IN_POINTERS;
- mem = _memory;
- }
-
- public void EnsureInitialized(object o)
- {
- if (_longWeakHandle != IntPtr.Zero)
- {
- return;
- }
-
- IntPtr newHandle = RuntimeImports.RhHandleAlloc(o, GCHandleType.WeakTrackResurrection);
- if (Interlocked.CompareExchange(ref _longWeakHandle, newHandle, IntPtr.Zero) != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(newHandle);
- }
- }
-
- ~ObjcTrackingInformation()
- {
- if (_longWeakHandle != IntPtr.Zero && RuntimeImports.RhHandleGet(_longWeakHandle) != null)
- {
- GC.ReRegisterForFinalize(this);
- return;
- }
-
- if (_memory != IntPtr.Zero)
- {
- NativeMemory.Free((void*)_memory);
- _memory = IntPtr.Zero;
- }
- if (_longWeakHandle != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(_longWeakHandle);
- _longWeakHandle = IntPtr.Zero;
- }
- }
- }
+ private static bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
  }
 }

src/coreclr/vm/CMakeLists.txt

@@ -59,6 +59,7 @@ set(VM_SOURCES_DAC_AND_WKS_COMMON
  clsload.cpp
  codeman.cpp
  codeversion.cpp
+ conditionalweaktable.cpp
  contractimpl.cpp
  corhost.cpp
  crst.cpp
@@ -277,7 +278,6 @@ list(APPEND VM_HEADERS_DAC_AND_WKS_COMMON
 
 set(VM_SOURCES_DAC
  ${VM_SOURCES_DAC_AND_WKS_COMMON}
- conditionalweaktable.cpp # The usage of conditionalweaktable is only in the DAC, but we put the headers in the VM to enable validation.
 )
 
 set(VM_HEADERS_DAC

src/coreclr/vm/binder.cpp

@@ -21,7 +21,7 @@
 #include "sigbuilder.h"
 #include "configuration.h"
 #include "conditionalweaktable.h"
-#include "interoplibinterface_comwrappers.h"
+#include "interoplibinterface.h"
 #include "assemblynative.hpp"
 
 //

src/coreclr/vm/conditionalweaktable.cpp

@@ -4,11 +4,20 @@
 
 #include "conditionalweaktable.h"
 #include "gchandleutilities.h"
+
+#ifdef DACCESS_COMPILE
 #include "../debug/daccess/gcinterface.dac.h"
+#endif // DACCESS_COMPILE
 
 bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF* value)
 {
- STANDARD_VM_CONTRACT;
+ CONTRACTL
+ {
+ NOTHROW;
+ GC_NOTRIGGER;
+ MODE_ANY;
+ }
+ CONTRACTL_END;
  SUPPORTS_DAC;
  _ASSERTE(key != nullptr && value != nullptr);
 
@@ -24,11 +33,19 @@ bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF*
  int bucket = hashCode & (_buckets->GetNumComponents() - 1);
  PTR_int32_t buckets = _buckets->GetDirectPointerToNonObjectElements();
  DPTR(Entry) entries = _entries->GetDirectPointerToNonObjectElements();
+
  for (int entriesIndex = buckets[bucket]; entriesIndex != -1; entriesIndex = entries[entriesIndex].Next)
  {
- if (entries[entriesIndex].HashCode == hashCode && ObjectFromHandle(entries[entriesIndex].depHnd) == key)
+ const Entry& entry = entries[entriesIndex];
+ if (entry.HashCode == hashCode && ObjectFromHandle(entry.depHnd) == key)
  {
- *value = HndGetHandleExtraInfo(entries[entriesIndex].depHnd);
+#ifdef DACCESS_COMPILE
+ // In the DACCESS_COMPILE, the handle helper is directly accessible.
+ *value = GetDependentHandleSecondary(entry.depHnd);
+#else
+ IGCHandleManager* mgr = GCHandleUtilities::GetGCHandleManager();
+ *value = ObjectToOBJECTREF(mgr->GetDependentHandleSecondary(entry.depHnd));
+#endif // !DACCESS_COMPILE
  return true;
  }
  }

src/coreclr/vm/conditionalweaktable.h

@@ -39,22 +39,20 @@ class ConditionalWeakTableContainerObject final : public Object
  ENTRYARRAYREF _entries;
 
 public:
-#ifdef DACCESS_COMPILE
  bool TryGetValue(OBJECTREF key, OBJECTREF* value);
-#endif
 };
 
 class ConditionalWeakTableObject final : public Object
 {
  friend class CoreLibBinder;
  OBJECTREF _lock;
- VolatilePtr<ConditionalWeakTableContainerObject, CONDITIONAL_WEAK_TABLE_CONTAINER_REF> _container;
+ VolatilePtr<ConditionalWeakTableContainerObject> _container;
 public:
-#ifdef DACCESS_COMPILE
- // Currently, we only use this for access from the DAC, so we don't need to worry about
- // locking or tracking the active enumerator count.
- // If we need to use this in a context where the runtime isn't suspended, we need to add
- // the locking and tracking support.
+ // This helper can be used when the runtime is suspended (for example, DAC access
+ // or Objective-C interop callbacks that run under GC suspension). During suspension
+ // the table shape is stable since no mutations can run, so lock-free lookup is safe.
+ // If we need to use this in a context where the runtime isn't suspended, we need to
+ // add locking and active enumerator tracking support.
  template<typename TKey, typename TValue>
  bool TryGetValue(TKey key, TValue* value)
  {
@@ -67,10 +65,8 @@ class ConditionalWeakTableObject final : public Object
  {
  *value = (TValue)valueObj;
  }
-
  return found;
  }
-#endif
 };
 
 #endif // CONDITIONAL_WEAK_TABLE_H

src/coreclr/vm/corelib.h

@@ -460,6 +460,9 @@ DEFINE_FIELD_U(_buckets, GCHandleSetObject, _buckets)
 #ifdef FEATURE_OBJCMARSHAL
 DEFINE_CLASS(OBJCMARSHAL, ObjectiveC, ObjectiveCMarshal)
 DEFINE_METHOD(OBJCMARSHAL, INVOKEUNHANDLEDEXCEPTIONPROPAGATION, InvokeUnhandledExceptionPropagation, SM_PtrException_IntPtr_PtrIntPtr_PtrException_RetVoidPtr)
+DEFINE_FIELD(OBJCMARSHAL, OBJECTS, s_objects)
+DEFINE_CLASS_U(ObjectiveC, ObjectiveCMarshal+ObjcTrackingInformation, ObjcTrackingInformationObject)
+DEFINE_FIELD_U(_memory, ObjcTrackingInformationObject, _memory)
 #endif // FEATURE_OBJCMARSHAL
 
 DEFINE_CLASS_U(Interop, TypeMapLazyDictionary+CallbackContext, CallbackContext)

src/coreclr/vm/datadescriptor/datadescriptor.inc

@@ -220,9 +220,6 @@ CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCW, cdac_data<InteropSyncBlock
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, RCW, cdac_data<InteropSyncBlockInfo>::RCW)
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCF, cdac_data<InteropSyncBlockInfo>::CCF)
 #endif // FEATURE_COMINTEROP
-#ifdef FEATURE_OBJCMARSHAL
-CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, TaggedMemory, cdac_data<InteropSyncBlockInfo>::TaggedMemory)
-#endif // FEATURE_OBJCMARSHAL
 CDAC_TYPE_END(InteropSyncBlockInfo)
 
 CDAC_TYPE_BEGIN(SyncBlock)

src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeHelpers.CoreCLR.cs

@@ -844,6 +844,9 @@ internal unsafe struct MethodTable
 #if FEATURE_TYPEEQUIVALENCE
  private const uint enum_flag_HasTypeEquivalence = 0x02000000;
 #endif // FEATURE_TYPEEQUIVALENCE
+#if FEATURE_OBJCMARSHAL
+ private const uint enum_flag_IsTrackedReferenceWithFinalizer = 0x04000000;
+#endif // FEATURE_OBJCMARSHAL
  private const uint enum_flag_HasFinalizer = 0x00100000;
  private const uint enum_flag_Collectible = 0x00200000;
  private const uint enum_flag_Category_Mask = 0x000F0000;
@@ -904,6 +907,10 @@ internal unsafe struct MethodTable
  public bool HasTypeEquivalence => (Flags & enum_flag_HasTypeEquivalence) != 0;
 #endif // FEATURE_TYPEEQUIVALENCE
 
+#if FEATURE_OBJCMARSHAL
+ public bool IsTrackedReferenceWithFinalizer => (Flags & enum_flag_IsTrackedReferenceWithFinalizer) != 0;
+#endif // FEATURE_OBJCMARSHAL
+
  public bool HasFinalizer => (Flags & enum_flag_HasFinalizer) != 0;
 
  public bool IsCollectible => (Flags & enum_flag_Collectible) != 0;

src/coreclr/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.CoreCLR.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Diagnostics;
 using System.Runtime.CompilerServices;
 using System.Runtime.Versioning;
 
@@ -31,19 +32,35 @@ private static partial bool TrySetGlobalMessageSendCallback(
  private static unsafe partial bool TryInitializeReferenceTracker(
  delegate* unmanaged<void> beginEndCallback,
  delegate* unmanaged<IntPtr, int> isReferencedCallback,
- delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization);
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization,
+ ObjectHandleOnStack objectTrackingInfoTable);
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_CreateReferenceTrackingHandle")]
- private static partial IntPtr CreateReferenceTrackingHandleInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static bool TryInitializeReferenceTracker(
+ delegate* unmanaged<void> beginEndCallback,
+ delegate* unmanaged<IntPtr, int> isReferencedCallback,
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization)
+ {
+ // Make a local of the readonly field because it needs to be passed by ref to a QCall
+ // and it is marked as readonly to prevent accidental reassignment.
+ ConditionalWeakTable<object, ObjcTrackingInformation> objects = s_objects;
+ bool result = TryInitializeReferenceTracker(
+ beginEndCallback,
+ isReferencedCallback,
+ trackedObjectEnteredFinalization,
+ ObjectHandleOnStack.Create(ref objects));
+ Debug.Assert(object.ReferenceEquals(objects, s_objects));
+
+ return result;
+ }
+
+ [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_AllocateReferenceTrackingHandle")]
+ private static partial IntPtr AllocateReferenceTrackingHandle(ObjectHandleOnStack obj);
+
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => AllocateReferenceTrackingHandle(ObjectHandleOnStack.Create(ref obj));
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_GetOrCreateReferenceTrackingMemory")]
- private static partial void GetOrCreateReferenceTrackingMemoryInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static unsafe bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
 
  [UnmanagedCallersOnly]
  internal static unsafe void* InvokeUnhandledExceptionPropagation(Exception* pExceptionArg, IntPtr methodDesc, IntPtr* pContext, Exception* pException)

src/coreclr/debug/daccess/request.cpp

@@ -23,6 +23,10 @@
 #include <interoplibabi.h>
 #endif // FEATURE_COMWRAPPERS
 
+#if defined(FEATURE_OBJCMARSHAL)
+#include <interoplibinterface.h>
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 // It is unfortunate having to include this header just to get the definition of GenericModeBlock
 #include <msodw.h>
@@ -2351,7 +2355,7 @@ ClrDataAccess::GetObjectData(CLRDATA_ADDRESS addr, struct DacpObjectData *object
  objectData->ElementTypeHandle = (CLRDATA_ADDRESS)(thElem.AsTAddr());
  objectData->dwRank = mt->GetRank();
  objectData->dwNumComponents = pArrayObj->GetNumComponents ();
- objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetDataPtr (TRUE));
+ objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetGCSafeDataPtr());
  objectData->ArrayBoundsPtr = HOST_CDADDR(pArrayObj->GetBoundsPtr());
  objectData->ArrayLowerBoundsPtr = HOST_CDADDR(pArrayObj->GetLowerBoundsPtr());
  }
@@ -5393,21 +5397,26 @@ namespace
 #ifdef FEATURE_OBJCMARSHAL
  EX_TRY_ALLOW_DATATARGET_MISSING_MEMORY
  {
- PTR_SyncBlock pSyncBlk = DACGetSyncBlockFromObjectPointer(CLRDATA_ADDRESS_TO_TADDR(objAddr), target);
- if (pSyncBlk != NULL)
+ if (g_ObjectiveCTrackingInfoTable != NULL)
  {
-PTR_InteropSyncBlockInfo pInfo = pSyncBlk->GetInteropInfoNoCreate();
- if (pInfo != NULL)
+CONDITIONAL_WEAK_TABLE_REF trackingTable = (CONDITIONAL_WEAK_TABLE_REF)ObjectFromHandle(g_ObjectiveCTrackingInfoTable);
+ if (trackingTable != NULL)
  {
- CLRDATA_ADDRESS taggedMemoryLocal = PTR_CDADDR(pInfo->GetTaggedMemory());
- if (taggedMemoryLocal != NULL)
+ OBJECTREF object = OBJECTREF(CLRDATA_ADDRESS_TO_TADDR(objAddr));
+ OBJC_TRACKING_INFO_REF trackingInfo = NULL;
+ if (trackingTable->TryGetValue(object, &trackingInfo) && trackingInfo != NULL)
  {
- hasTaggedMemory = TRUE;
- if (taggedMemory)
- *taggedMemory = taggedMemoryLocal;
+ TADDR memory = (TADDR)trackingInfo->_memory;
+ if (memory != NULL)
+ {
+ hasTaggedMemory = TRUE;
+ if (taggedMemory)
+ *taggedMemory = (CLRDATA_ADDRESS)memory;
 
- if (taggedMemorySizeInBytes)
- *taggedMemorySizeInBytes = pInfo->GetTaggedMemorySizeInBytes();
+ constexpr int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ if (taggedMemorySizeInBytes)
+ *taggedMemorySizeInBytes = TAGGED_MEMORY_SIZE_IN_POINTERS * sizeof(TADDR);
+ }
  }
  }
  }

src/coreclr/inc/dacvars.h

@@ -214,6 +214,10 @@ DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_pRCWCleanupList, ::g_pRCWCleanupList)
 DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_knownQueryInterfaceImplementations, InteropLib::ABI::g_knownQueryInterfaceImplementations)
 #endif // FEATURE_COMWRAPPERS
 
+#ifdef FEATURE_OBJCMARSHAL
+DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_ObjectiveCTrackingInfoTable, ::g_ObjectiveCTrackingInfoTable)
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeLoadedBaseAddress, ::g_runtimeLoadedBaseAddress)
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeVirtualSize, ::g_runtimeVirtualSize)

src/coreclr/nativeaot/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.NativeAot.cs

@@ -11,8 +11,6 @@ namespace System.Runtime.InteropServices.ObjectiveC
  public static unsafe partial class ObjectiveCMarshal
  {
  private static readonly IntPtr[] s_ObjcMessageSendFunctions = new IntPtr[(int)MessageSendFunction.MsgSendSuperStret + 1];
- private static bool s_initialized;
- private static readonly ConditionalWeakTable<object, ObjcTrackingInformation> s_objects = new();
  private static delegate* unmanaged[SuppressGCTransition]<void*, int> s_IsTrackedReferenceCallback;
  private static delegate* unmanaged[SuppressGCTransition]<void*, void> s_OnEnteredFinalizerQueueCallback;
 
@@ -116,94 +114,13 @@ private static bool TryInitializeReferenceTracker(
 
  s_IsTrackedReferenceCallback = (delegate* unmanaged[SuppressGCTransition]<void*, int>)isReferencedCallback;
  s_OnEnteredFinalizerQueueCallback = (delegate* unmanaged[SuppressGCTransition]<void*, void>)trackedObjectEnteredFinalization;
- s_initialized = true;
-
  return true;
  }
 
- private static IntPtr CreateReferenceTrackingHandleInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- // Rely on GetOrCreateReferenceTrackingMemoryInternal for state checking.
- GetOrCreateReferenceTrackingMemoryInternal(obj, out memInSizeT, out mem);
- return RuntimeImports.RhHandleAllocRefCounted(obj);
- }
-
- private static void GetOrCreateReferenceTrackingMemoryInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- if (!s_initialized)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCMarshalNotInitialized);
- }
-
- if (!obj.GetMethodTable()->IsTrackedReferenceWithFinalizer)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCTypeNoFinalizer);
- }
-
- var trackerInfo = s_objects.GetOrAdd(obj, static o => new ObjcTrackingInformation());
- trackerInfo.EnsureInitialized(obj);
- trackerInfo.GetTaggedMemory(out memInSizeT, out mem);
- }
-
- internal class ObjcTrackingInformation
- {
- // This matches the CoreCLR implementation. See
- // InteropSyncBlockInfo::m_taggedAlloc in syncblk.h .
- private const int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => RuntimeImports.RhHandleAllocRefCounted(obj);
 
- internal IntPtr _memory;
- private IntPtr _longWeakHandle;
-
- public ObjcTrackingInformation()
- {
- _memory = (IntPtr)NativeMemory.AllocZeroed(TAGGED_MEMORY_SIZE_IN_POINTERS * (nuint)IntPtr.Size);
- }
-
- public void GetTaggedMemory(out int memInSizeT, out IntPtr mem)
- {
- memInSizeT = TAGGED_MEMORY_SIZE_IN_POINTERS;
- mem = _memory;
- }
-
- public void EnsureInitialized(object o)
- {
- if (_longWeakHandle != IntPtr.Zero)
- {
- return;
- }
-
- IntPtr newHandle = RuntimeImports.RhHandleAlloc(o, GCHandleType.WeakTrackResurrection);
- if (Interlocked.CompareExchange(ref _longWeakHandle, newHandle, IntPtr.Zero) != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(newHandle);
- }
- }
-
- ~ObjcTrackingInformation()
- {
- if (_longWeakHandle != IntPtr.Zero && RuntimeImports.RhHandleGet(_longWeakHandle) != null)
- {
- GC.ReRegisterForFinalize(this);
- return;
- }
-
- if (_memory != IntPtr.Zero)
- {
- NativeMemory.Free((void*)_memory);
- _memory = IntPtr.Zero;
- }
- if (_longWeakHandle != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(_longWeakHandle);
- _longWeakHandle = IntPtr.Zero;
- }
- }
- }
+ private static bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
  }
 }

src/coreclr/vm/CMakeLists.txt

@@ -59,6 +59,7 @@ set(VM_SOURCES_DAC_AND_WKS_COMMON
  clsload.cpp
  codeman.cpp
  codeversion.cpp
+ conditionalweaktable.cpp
  contractimpl.cpp
  corhost.cpp
  crst.cpp
@@ -277,7 +278,6 @@ list(APPEND VM_HEADERS_DAC_AND_WKS_COMMON
 
 set(VM_SOURCES_DAC
  ${VM_SOURCES_DAC_AND_WKS_COMMON}
- conditionalweaktable.cpp # The usage of conditionalweaktable is only in the DAC, but we put the headers in the VM to enable validation.
 )
 
 set(VM_HEADERS_DAC

src/coreclr/vm/binder.cpp

@@ -21,7 +21,7 @@
 #include "sigbuilder.h"
 #include "configuration.h"
 #include "conditionalweaktable.h"
-#include "interoplibinterface_comwrappers.h"
+#include "interoplibinterface.h"
 #include "assemblynative.hpp"
 
 //

src/coreclr/vm/conditionalweaktable.cpp

@@ -4,11 +4,20 @@
 
 #include "conditionalweaktable.h"
 #include "gchandleutilities.h"
+
+#ifdef DACCESS_COMPILE
 #include "../debug/daccess/gcinterface.dac.h"
+#endif // DACCESS_COMPILE
 
 bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF* value)
 {
- STANDARD_VM_CONTRACT;
+ CONTRACTL
+ {
+ NOTHROW;
+ GC_NOTRIGGER;
+ MODE_ANY;
+ }
+ CONTRACTL_END;
  SUPPORTS_DAC;
  _ASSERTE(key != nullptr && value != nullptr);
 
@@ -24,11 +33,19 @@ bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF*
  int bucket = hashCode & (_buckets->GetNumComponents() - 1);
  PTR_int32_t buckets = _buckets->GetDirectPointerToNonObjectElements();
  DPTR(Entry) entries = _entries->GetDirectPointerToNonObjectElements();
+
  for (int entriesIndex = buckets[bucket]; entriesIndex != -1; entriesIndex = entries[entriesIndex].Next)
  {
- if (entries[entriesIndex].HashCode == hashCode && ObjectFromHandle(entries[entriesIndex].depHnd) == key)
+ const Entry& entry = entries[entriesIndex];
+ if (entry.HashCode == hashCode && ObjectFromHandle(entry.depHnd) == key)
  {
- *value = HndGetHandleExtraInfo(entries[entriesIndex].depHnd);
+#ifdef DACCESS_COMPILE
+ // In the DACCESS_COMPILE, the handle helper is directly accessible.
+ *value = GetDependentHandleSecondary(entry.depHnd);
+#else
+ IGCHandleManager* mgr = GCHandleUtilities::GetGCHandleManager();
+ *value = ObjectToOBJECTREF(mgr->GetDependentHandleSecondary(entry.depHnd));
+#endif // !DACCESS_COMPILE
  return true;
  }
  }

src/coreclr/vm/conditionalweaktable.h

@@ -39,22 +39,20 @@ class ConditionalWeakTableContainerObject final : public Object
  ENTRYARRAYREF _entries;
 
 public:
-#ifdef DACCESS_COMPILE
  bool TryGetValue(OBJECTREF key, OBJECTREF* value);
-#endif
 };
 
 class ConditionalWeakTableObject final : public Object
 {
  friend class CoreLibBinder;
  OBJECTREF _lock;
- VolatilePtr<ConditionalWeakTableContainerObject, CONDITIONAL_WEAK_TABLE_CONTAINER_REF> _container;
+ VolatilePtr<ConditionalWeakTableContainerObject> _container;
 public:
-#ifdef DACCESS_COMPILE
- // Currently, we only use this for access from the DAC, so we don't need to worry about
- // locking or tracking the active enumerator count.
- // If we need to use this in a context where the runtime isn't suspended, we need to add
- // the locking and tracking support.
+ // This helper can be used when the runtime is suspended (for example, DAC access
+ // or Objective-C interop callbacks that run under GC suspension). During suspension
+ // the table shape is stable since no mutations can run, so lock-free lookup is safe.
+ // If we need to use this in a context where the runtime isn't suspended, we need to
+ // add locking and active enumerator tracking support.
  template<typename TKey, typename TValue>
  bool TryGetValue(TKey key, TValue* value)
  {
@@ -67,10 +65,8 @@ class ConditionalWeakTableObject final : public Object
  {
  *value = (TValue)valueObj;
  }
-
  return found;
  }
-#endif
 };
 
 #endif // CONDITIONAL_WEAK_TABLE_H

src/coreclr/vm/corelib.h

@@ -460,6 +460,9 @@ DEFINE_FIELD_U(_buckets, GCHandleSetObject, _buckets)
 #ifdef FEATURE_OBJCMARSHAL
 DEFINE_CLASS(OBJCMARSHAL, ObjectiveC, ObjectiveCMarshal)
 DEFINE_METHOD(OBJCMARSHAL, INVOKEUNHANDLEDEXCEPTIONPROPAGATION, InvokeUnhandledExceptionPropagation, SM_PtrException_IntPtr_PtrIntPtr_PtrException_RetVoidPtr)
+DEFINE_FIELD(OBJCMARSHAL, OBJECTS, s_objects)
+DEFINE_CLASS_U(ObjectiveC, ObjectiveCMarshal+ObjcTrackingInformation, ObjcTrackingInformationObject)
+DEFINE_FIELD_U(_memory, ObjcTrackingInformationObject, _memory)
 #endif // FEATURE_OBJCMARSHAL
 
 DEFINE_CLASS_U(Interop, TypeMapLazyDictionary+CallbackContext, CallbackContext)

src/coreclr/vm/datadescriptor/datadescriptor.inc

@@ -220,9 +220,6 @@ CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCW, cdac_data<InteropSyncBlock
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, RCW, cdac_data<InteropSyncBlockInfo>::RCW)
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCF, cdac_data<InteropSyncBlockInfo>::CCF)
 #endif // FEATURE_COMINTEROP
-#ifdef FEATURE_OBJCMARSHAL
-CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, TaggedMemory, cdac_data<InteropSyncBlockInfo>::TaggedMemory)
-#endif // FEATURE_OBJCMARSHAL
 CDAC_TYPE_END(InteropSyncBlockInfo)
 
 CDAC_TYPE_BEGIN(SyncBlock)

src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeHelpers.CoreCLR.cs

@@ -844,6 +844,9 @@ internal unsafe struct MethodTable
 #if FEATURE_TYPEEQUIVALENCE
  private const uint enum_flag_HasTypeEquivalence = 0x02000000;
 #endif // FEATURE_TYPEEQUIVALENCE
+#if FEATURE_OBJCMARSHAL
+ private const uint enum_flag_IsTrackedReferenceWithFinalizer = 0x04000000;
+#endif // FEATURE_OBJCMARSHAL
  private const uint enum_flag_HasFinalizer = 0x00100000;
  private const uint enum_flag_Collectible = 0x00200000;
  private const uint enum_flag_Category_Mask = 0x000F0000;
@@ -904,6 +907,10 @@ internal unsafe struct MethodTable
  public bool HasTypeEquivalence => (Flags & enum_flag_HasTypeEquivalence) != 0;
 #endif // FEATURE_TYPEEQUIVALENCE
 
+#if FEATURE_OBJCMARSHAL
+ public bool IsTrackedReferenceWithFinalizer => (Flags & enum_flag_IsTrackedReferenceWithFinalizer) != 0;
+#endif // FEATURE_OBJCMARSHAL
+
  public bool HasFinalizer => (Flags & enum_flag_HasFinalizer) != 0;
 
  public bool IsCollectible => (Flags & enum_flag_Collectible) != 0;

src/coreclr/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.CoreCLR.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Diagnostics;
 using System.Runtime.CompilerServices;
 using System.Runtime.Versioning;
 
@@ -31,19 +32,35 @@ private static partial bool TrySetGlobalMessageSendCallback(
  private static unsafe partial bool TryInitializeReferenceTracker(
  delegate* unmanaged<void> beginEndCallback,
  delegate* unmanaged<IntPtr, int> isReferencedCallback,
- delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization);
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization,
+ ObjectHandleOnStack objectTrackingInfoTable);
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_CreateReferenceTrackingHandle")]
- private static partial IntPtr CreateReferenceTrackingHandleInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static bool TryInitializeReferenceTracker(
+ delegate* unmanaged<void> beginEndCallback,
+ delegate* unmanaged<IntPtr, int> isReferencedCallback,
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization)
+ {
+ // Make a local of the readonly field because it needs to be passed by ref to a QCall
+ // and it is marked as readonly to prevent accidental reassignment.
+ ConditionalWeakTable<object, ObjcTrackingInformation> objects = s_objects;
+ bool result = TryInitializeReferenceTracker(
+ beginEndCallback,
+ isReferencedCallback,
+ trackedObjectEnteredFinalization,
+ ObjectHandleOnStack.Create(ref objects));
+ Debug.Assert(object.ReferenceEquals(objects, s_objects));
+
+ return result;
+ }
+
+ [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_AllocateReferenceTrackingHandle")]
+ private static partial IntPtr AllocateReferenceTrackingHandle(ObjectHandleOnStack obj);
+
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => AllocateReferenceTrackingHandle(ObjectHandleOnStack.Create(ref obj));
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_GetOrCreateReferenceTrackingMemory")]
- private static partial void GetOrCreateReferenceTrackingMemoryInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static unsafe bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
 
  [UnmanagedCallersOnly]
  internal static unsafe void* InvokeUnhandledExceptionPropagation(Exception* pExceptionArg, IntPtr methodDesc, IntPtr* pContext, Exception* pException)

src/coreclr/debug/daccess/request.cpp

@@ -23,6 +23,10 @@
 #include <interoplibabi.h>
 #endif // FEATURE_COMWRAPPERS
 
+#if defined(FEATURE_OBJCMARSHAL)
+#include <interoplibinterface.h>
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 // It is unfortunate having to include this header just to get the definition of GenericModeBlock
 #include <msodw.h>
@@ -2351,7 +2355,7 @@ ClrDataAccess::GetObjectData(CLRDATA_ADDRESS addr, struct DacpObjectData *object
  objectData->ElementTypeHandle = (CLRDATA_ADDRESS)(thElem.AsTAddr());
  objectData->dwRank = mt->GetRank();
  objectData->dwNumComponents = pArrayObj->GetNumComponents ();
- objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetDataPtr (TRUE));
+ objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetGCSafeDataPtr());
  objectData->ArrayBoundsPtr = HOST_CDADDR(pArrayObj->GetBoundsPtr());
  objectData->ArrayLowerBoundsPtr = HOST_CDADDR(pArrayObj->GetLowerBoundsPtr());
  }
@@ -5393,21 +5397,26 @@ namespace
 #ifdef FEATURE_OBJCMARSHAL
  EX_TRY_ALLOW_DATATARGET_MISSING_MEMORY
  {
- PTR_SyncBlock pSyncBlk = DACGetSyncBlockFromObjectPointer(CLRDATA_ADDRESS_TO_TADDR(objAddr), target);
- if (pSyncBlk != NULL)
+ if (g_ObjectiveCTrackingInfoTable != NULL)
  {
-PTR_InteropSyncBlockInfo pInfo = pSyncBlk->GetInteropInfoNoCreate();
- if (pInfo != NULL)
+CONDITIONAL_WEAK_TABLE_REF trackingTable = (CONDITIONAL_WEAK_TABLE_REF)ObjectFromHandle(g_ObjectiveCTrackingInfoTable);
+ if (trackingTable != NULL)
  {
- CLRDATA_ADDRESS taggedMemoryLocal = PTR_CDADDR(pInfo->GetTaggedMemory());
- if (taggedMemoryLocal != NULL)
+ OBJECTREF object = OBJECTREF(CLRDATA_ADDRESS_TO_TADDR(objAddr));
+ OBJC_TRACKING_INFO_REF trackingInfo = NULL;
+ if (trackingTable->TryGetValue(object, &trackingInfo) && trackingInfo != NULL)
  {
- hasTaggedMemory = TRUE;
- if (taggedMemory)
- *taggedMemory = taggedMemoryLocal;
+ TADDR memory = (TADDR)trackingInfo->_memory;
+ if (memory != NULL)
+ {
+ hasTaggedMemory = TRUE;
+ if (taggedMemory)
+ *taggedMemory = (CLRDATA_ADDRESS)memory;
 
- if (taggedMemorySizeInBytes)
- *taggedMemorySizeInBytes = pInfo->GetTaggedMemorySizeInBytes();
+ constexpr int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ if (taggedMemorySizeInBytes)
+ *taggedMemorySizeInBytes = TAGGED_MEMORY_SIZE_IN_POINTERS * sizeof(TADDR);
+ }
  }
  }
  }

src/coreclr/inc/dacvars.h

@@ -214,6 +214,10 @@ DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_pRCWCleanupList, ::g_pRCWCleanupList)
 DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_knownQueryInterfaceImplementations, InteropLib::ABI::g_knownQueryInterfaceImplementations)
 #endif // FEATURE_COMWRAPPERS
 
+#ifdef FEATURE_OBJCMARSHAL
+DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_ObjectiveCTrackingInfoTable, ::g_ObjectiveCTrackingInfoTable)
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeLoadedBaseAddress, ::g_runtimeLoadedBaseAddress)
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeVirtualSize, ::g_runtimeVirtualSize)

src/coreclr/nativeaot/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.NativeAot.cs

@@ -11,8 +11,6 @@ namespace System.Runtime.InteropServices.ObjectiveC
  public static unsafe partial class ObjectiveCMarshal
  {
  private static readonly IntPtr[] s_ObjcMessageSendFunctions = new IntPtr[(int)MessageSendFunction.MsgSendSuperStret + 1];
- private static bool s_initialized;
- private static readonly ConditionalWeakTable<object, ObjcTrackingInformation> s_objects = new();
  private static delegate* unmanaged[SuppressGCTransition]<void*, int> s_IsTrackedReferenceCallback;
  private static delegate* unmanaged[SuppressGCTransition]<void*, void> s_OnEnteredFinalizerQueueCallback;
 
@@ -116,94 +114,13 @@ private static bool TryInitializeReferenceTracker(
 
  s_IsTrackedReferenceCallback = (delegate* unmanaged[SuppressGCTransition]<void*, int>)isReferencedCallback;
  s_OnEnteredFinalizerQueueCallback = (delegate* unmanaged[SuppressGCTransition]<void*, void>)trackedObjectEnteredFinalization;
- s_initialized = true;
-
  return true;
  }
 
- private static IntPtr CreateReferenceTrackingHandleInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- // Rely on GetOrCreateReferenceTrackingMemoryInternal for state checking.
- GetOrCreateReferenceTrackingMemoryInternal(obj, out memInSizeT, out mem);
- return RuntimeImports.RhHandleAllocRefCounted(obj);
- }
-
- private static void GetOrCreateReferenceTrackingMemoryInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- if (!s_initialized)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCMarshalNotInitialized);
- }
-
- if (!obj.GetMethodTable()->IsTrackedReferenceWithFinalizer)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCTypeNoFinalizer);
- }
-
- var trackerInfo = s_objects.GetOrAdd(obj, static o => new ObjcTrackingInformation());
- trackerInfo.EnsureInitialized(obj);
- trackerInfo.GetTaggedMemory(out memInSizeT, out mem);
- }
-
- internal class ObjcTrackingInformation
- {
- // This matches the CoreCLR implementation. See
- // InteropSyncBlockInfo::m_taggedAlloc in syncblk.h .
- private const int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => RuntimeImports.RhHandleAllocRefCounted(obj);
 
- internal IntPtr _memory;
- private IntPtr _longWeakHandle;
-
- public ObjcTrackingInformation()
- {
- _memory = (IntPtr)NativeMemory.AllocZeroed(TAGGED_MEMORY_SIZE_IN_POINTERS * (nuint)IntPtr.Size);
- }
-
- public void GetTaggedMemory(out int memInSizeT, out IntPtr mem)
- {
- memInSizeT = TAGGED_MEMORY_SIZE_IN_POINTERS;
- mem = _memory;
- }
-
- public void EnsureInitialized(object o)
- {
- if (_longWeakHandle != IntPtr.Zero)
- {
- return;
- }
-
- IntPtr newHandle = RuntimeImports.RhHandleAlloc(o, GCHandleType.WeakTrackResurrection);
- if (Interlocked.CompareExchange(ref _longWeakHandle, newHandle, IntPtr.Zero) != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(newHandle);
- }
- }
-
- ~ObjcTrackingInformation()
- {
- if (_longWeakHandle != IntPtr.Zero && RuntimeImports.RhHandleGet(_longWeakHandle) != null)
- {
- GC.ReRegisterForFinalize(this);
- return;
- }
-
- if (_memory != IntPtr.Zero)
- {
- NativeMemory.Free((void*)_memory);
- _memory = IntPtr.Zero;
- }
- if (_longWeakHandle != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(_longWeakHandle);
- _longWeakHandle = IntPtr.Zero;
- }
- }
- }
+ private static bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
  }
 }

src/coreclr/vm/CMakeLists.txt

@@ -59,6 +59,7 @@ set(VM_SOURCES_DAC_AND_WKS_COMMON
  clsload.cpp
  codeman.cpp
  codeversion.cpp
+ conditionalweaktable.cpp
  contractimpl.cpp
  corhost.cpp
  crst.cpp
@@ -277,7 +278,6 @@ list(APPEND VM_HEADERS_DAC_AND_WKS_COMMON
 
 set(VM_SOURCES_DAC
  ${VM_SOURCES_DAC_AND_WKS_COMMON}
- conditionalweaktable.cpp # The usage of conditionalweaktable is only in the DAC, but we put the headers in the VM to enable validation.
 )
 
 set(VM_HEADERS_DAC

src/coreclr/vm/binder.cpp

@@ -21,7 +21,7 @@
 #include "sigbuilder.h"
 #include "configuration.h"
 #include "conditionalweaktable.h"
-#include "interoplibinterface_comwrappers.h"
+#include "interoplibinterface.h"
 #include "assemblynative.hpp"
 
 //

src/coreclr/vm/conditionalweaktable.cpp

@@ -4,11 +4,20 @@
 
 #include "conditionalweaktable.h"
 #include "gchandleutilities.h"
+
+#ifdef DACCESS_COMPILE
 #include "../debug/daccess/gcinterface.dac.h"
+#endif // DACCESS_COMPILE
 
 bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF* value)
 {
- STANDARD_VM_CONTRACT;
+ CONTRACTL
+ {
+ NOTHROW;
+ GC_NOTRIGGER;
+ MODE_ANY;
+ }
+ CONTRACTL_END;
  SUPPORTS_DAC;
  _ASSERTE(key != nullptr && value != nullptr);
 
@@ -24,11 +33,19 @@ bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF*
  int bucket = hashCode & (_buckets->GetNumComponents() - 1);
  PTR_int32_t buckets = _buckets->GetDirectPointerToNonObjectElements();
  DPTR(Entry) entries = _entries->GetDirectPointerToNonObjectElements();
+
  for (int entriesIndex = buckets[bucket]; entriesIndex != -1; entriesIndex = entries[entriesIndex].Next)
  {
- if (entries[entriesIndex].HashCode == hashCode && ObjectFromHandle(entries[entriesIndex].depHnd) == key)
+ const Entry& entry = entries[entriesIndex];
+ if (entry.HashCode == hashCode && ObjectFromHandle(entry.depHnd) == key)
  {
- *value = HndGetHandleExtraInfo(entries[entriesIndex].depHnd);
+#ifdef DACCESS_COMPILE
+ // In the DACCESS_COMPILE, the handle helper is directly accessible.
+ *value = GetDependentHandleSecondary(entry.depHnd);
+#else
+ IGCHandleManager* mgr = GCHandleUtilities::GetGCHandleManager();
+ *value = ObjectToOBJECTREF(mgr->GetDependentHandleSecondary(entry.depHnd));
+#endif // !DACCESS_COMPILE
  return true;
  }
  }

src/coreclr/vm/conditionalweaktable.h

@@ -39,22 +39,20 @@ class ConditionalWeakTableContainerObject final : public Object
  ENTRYARRAYREF _entries;
 
 public:
-#ifdef DACCESS_COMPILE
  bool TryGetValue(OBJECTREF key, OBJECTREF* value);
-#endif
 };
 
 class ConditionalWeakTableObject final : public Object
 {
  friend class CoreLibBinder;
  OBJECTREF _lock;
- VolatilePtr<ConditionalWeakTableContainerObject, CONDITIONAL_WEAK_TABLE_CONTAINER_REF> _container;
+ VolatilePtr<ConditionalWeakTableContainerObject> _container;
 public:
-#ifdef DACCESS_COMPILE
- // Currently, we only use this for access from the DAC, so we don't need to worry about
- // locking or tracking the active enumerator count.
- // If we need to use this in a context where the runtime isn't suspended, we need to add
- // the locking and tracking support.
+ // This helper can be used when the runtime is suspended (for example, DAC access
+ // or Objective-C interop callbacks that run under GC suspension). During suspension
+ // the table shape is stable since no mutations can run, so lock-free lookup is safe.
+ // If we need to use this in a context where the runtime isn't suspended, we need to
+ // add locking and active enumerator tracking support.
  template<typename TKey, typename TValue>
  bool TryGetValue(TKey key, TValue* value)
  {
@@ -67,10 +65,8 @@ class ConditionalWeakTableObject final : public Object
  {
  *value = (TValue)valueObj;
  }
-
  return found;
  }
-#endif
 };
 
 #endif // CONDITIONAL_WEAK_TABLE_H

src/coreclr/vm/corelib.h

@@ -460,6 +460,9 @@ DEFINE_FIELD_U(_buckets, GCHandleSetObject, _buckets)
 #ifdef FEATURE_OBJCMARSHAL
 DEFINE_CLASS(OBJCMARSHAL, ObjectiveC, ObjectiveCMarshal)
 DEFINE_METHOD(OBJCMARSHAL, INVOKEUNHANDLEDEXCEPTIONPROPAGATION, InvokeUnhandledExceptionPropagation, SM_PtrException_IntPtr_PtrIntPtr_PtrException_RetVoidPtr)
+DEFINE_FIELD(OBJCMARSHAL, OBJECTS, s_objects)
+DEFINE_CLASS_U(ObjectiveC, ObjectiveCMarshal+ObjcTrackingInformation, ObjcTrackingInformationObject)
+DEFINE_FIELD_U(_memory, ObjcTrackingInformationObject, _memory)
 #endif // FEATURE_OBJCMARSHAL
 
 DEFINE_CLASS_U(Interop, TypeMapLazyDictionary+CallbackContext, CallbackContext)

src/coreclr/vm/datadescriptor/datadescriptor.inc

@@ -220,9 +220,6 @@ CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCW, cdac_data<InteropSyncBlock
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, RCW, cdac_data<InteropSyncBlockInfo>::RCW)
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCF, cdac_data<InteropSyncBlockInfo>::CCF)
 #endif // FEATURE_COMINTEROP
-#ifdef FEATURE_OBJCMARSHAL
-CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, TaggedMemory, cdac_data<InteropSyncBlockInfo>::TaggedMemory)
-#endif // FEATURE_OBJCMARSHAL
 CDAC_TYPE_END(InteropSyncBlockInfo)
 
 CDAC_TYPE_BEGIN(SyncBlock)

src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeHelpers.CoreCLR.cs

@@ -844,6 +844,9 @@ internal unsafe struct MethodTable
 #if FEATURE_TYPEEQUIVALENCE
  private const uint enum_flag_HasTypeEquivalence = 0x02000000;
 #endif // FEATURE_TYPEEQUIVALENCE
+#if FEATURE_OBJCMARSHAL
+ private const uint enum_flag_IsTrackedReferenceWithFinalizer = 0x04000000;
+#endif // FEATURE_OBJCMARSHAL
  private const uint enum_flag_HasFinalizer = 0x00100000;
  private const uint enum_flag_Collectible = 0x00200000;
  private const uint enum_flag_Category_Mask = 0x000F0000;
@@ -904,6 +907,10 @@ internal unsafe struct MethodTable
  public bool HasTypeEquivalence => (Flags & enum_flag_HasTypeEquivalence) != 0;
 #endif // FEATURE_TYPEEQUIVALENCE
 
+#if FEATURE_OBJCMARSHAL
+ public bool IsTrackedReferenceWithFinalizer => (Flags & enum_flag_IsTrackedReferenceWithFinalizer) != 0;
+#endif // FEATURE_OBJCMARSHAL
+
  public bool HasFinalizer => (Flags & enum_flag_HasFinalizer) != 0;
 
  public bool IsCollectible => (Flags & enum_flag_Collectible) != 0;

src/coreclr/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.CoreCLR.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Diagnostics;
 using System.Runtime.CompilerServices;
 using System.Runtime.Versioning;
 
@@ -31,19 +32,35 @@ private static partial bool TrySetGlobalMessageSendCallback(
  private static unsafe partial bool TryInitializeReferenceTracker(
  delegate* unmanaged<void> beginEndCallback,
  delegate* unmanaged<IntPtr, int> isReferencedCallback,
- delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization);
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization,
+ ObjectHandleOnStack objectTrackingInfoTable);
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_CreateReferenceTrackingHandle")]
- private static partial IntPtr CreateReferenceTrackingHandleInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static bool TryInitializeReferenceTracker(
+ delegate* unmanaged<void> beginEndCallback,
+ delegate* unmanaged<IntPtr, int> isReferencedCallback,
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization)
+ {
+ // Make a local of the readonly field because it needs to be passed by ref to a QCall
+ // and it is marked as readonly to prevent accidental reassignment.
+ ConditionalWeakTable<object, ObjcTrackingInformation> objects = s_objects;
+ bool result = TryInitializeReferenceTracker(
+ beginEndCallback,
+ isReferencedCallback,
+ trackedObjectEnteredFinalization,
+ ObjectHandleOnStack.Create(ref objects));
+ Debug.Assert(object.ReferenceEquals(objects, s_objects));
+
+ return result;
+ }
+
+ [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_AllocateReferenceTrackingHandle")]
+ private static partial IntPtr AllocateReferenceTrackingHandle(ObjectHandleOnStack obj);
+
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => AllocateReferenceTrackingHandle(ObjectHandleOnStack.Create(ref obj));
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_GetOrCreateReferenceTrackingMemory")]
- private static partial void GetOrCreateReferenceTrackingMemoryInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static unsafe bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
 
  [UnmanagedCallersOnly]
  internal static unsafe void* InvokeUnhandledExceptionPropagation(Exception* pExceptionArg, IntPtr methodDesc, IntPtr* pContext, Exception* pException)

src/coreclr/debug/daccess/request.cpp

@@ -23,6 +23,10 @@
 #include <interoplibabi.h>
 #endif // FEATURE_COMWRAPPERS
 
+#if defined(FEATURE_OBJCMARSHAL)
+#include <interoplibinterface.h>
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 // It is unfortunate having to include this header just to get the definition of GenericModeBlock
 #include <msodw.h>
@@ -2351,7 +2355,7 @@ ClrDataAccess::GetObjectData(CLRDATA_ADDRESS addr, struct DacpObjectData *object
  objectData->ElementTypeHandle = (CLRDATA_ADDRESS)(thElem.AsTAddr());
  objectData->dwRank = mt->GetRank();
  objectData->dwNumComponents = pArrayObj->GetNumComponents ();
- objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetDataPtr (TRUE));
+ objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetGCSafeDataPtr());
  objectData->ArrayBoundsPtr = HOST_CDADDR(pArrayObj->GetBoundsPtr());
  objectData->ArrayLowerBoundsPtr = HOST_CDADDR(pArrayObj->GetLowerBoundsPtr());
  }
@@ -5393,21 +5397,26 @@ namespace
 #ifdef FEATURE_OBJCMARSHAL
  EX_TRY_ALLOW_DATATARGET_MISSING_MEMORY
  {
- PTR_SyncBlock pSyncBlk = DACGetSyncBlockFromObjectPointer(CLRDATA_ADDRESS_TO_TADDR(objAddr), target);
- if (pSyncBlk != NULL)
+ if (g_ObjectiveCTrackingInfoTable != NULL)
  {
-PTR_InteropSyncBlockInfo pInfo = pSyncBlk->GetInteropInfoNoCreate();
- if (pInfo != NULL)
+CONDITIONAL_WEAK_TABLE_REF trackingTable = (CONDITIONAL_WEAK_TABLE_REF)ObjectFromHandle(g_ObjectiveCTrackingInfoTable);
+ if (trackingTable != NULL)
  {
- CLRDATA_ADDRESS taggedMemoryLocal = PTR_CDADDR(pInfo->GetTaggedMemory());
- if (taggedMemoryLocal != NULL)
+ OBJECTREF object = OBJECTREF(CLRDATA_ADDRESS_TO_TADDR(objAddr));
+ OBJC_TRACKING_INFO_REF trackingInfo = NULL;
+ if (trackingTable->TryGetValue(object, &trackingInfo) && trackingInfo != NULL)
  {
- hasTaggedMemory = TRUE;
- if (taggedMemory)
- *taggedMemory = taggedMemoryLocal;
+ TADDR memory = (TADDR)trackingInfo->_memory;
+ if (memory != NULL)
+ {
+ hasTaggedMemory = TRUE;
+ if (taggedMemory)
+ *taggedMemory = (CLRDATA_ADDRESS)memory;
 
- if (taggedMemorySizeInBytes)
- *taggedMemorySizeInBytes = pInfo->GetTaggedMemorySizeInBytes();
+ constexpr int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ if (taggedMemorySizeInBytes)
+ *taggedMemorySizeInBytes = TAGGED_MEMORY_SIZE_IN_POINTERS * sizeof(TADDR);
+ }
  }
  }
  }

src/coreclr/inc/dacvars.h

@@ -214,6 +214,10 @@ DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_pRCWCleanupList, ::g_pRCWCleanupList)
 DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_knownQueryInterfaceImplementations, InteropLib::ABI::g_knownQueryInterfaceImplementations)
 #endif // FEATURE_COMWRAPPERS
 
+#ifdef FEATURE_OBJCMARSHAL
+DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_ObjectiveCTrackingInfoTable, ::g_ObjectiveCTrackingInfoTable)
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeLoadedBaseAddress, ::g_runtimeLoadedBaseAddress)
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeVirtualSize, ::g_runtimeVirtualSize)

src/coreclr/nativeaot/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.NativeAot.cs

@@ -11,8 +11,6 @@ namespace System.Runtime.InteropServices.ObjectiveC
  public static unsafe partial class ObjectiveCMarshal
  {
  private static readonly IntPtr[] s_ObjcMessageSendFunctions = new IntPtr[(int)MessageSendFunction.MsgSendSuperStret + 1];
- private static bool s_initialized;
- private static readonly ConditionalWeakTable<object, ObjcTrackingInformation> s_objects = new();
  private static delegate* unmanaged[SuppressGCTransition]<void*, int> s_IsTrackedReferenceCallback;
  private static delegate* unmanaged[SuppressGCTransition]<void*, void> s_OnEnteredFinalizerQueueCallback;
 
@@ -116,94 +114,13 @@ private static bool TryInitializeReferenceTracker(
 
  s_IsTrackedReferenceCallback = (delegate* unmanaged[SuppressGCTransition]<void*, int>)isReferencedCallback;
  s_OnEnteredFinalizerQueueCallback = (delegate* unmanaged[SuppressGCTransition]<void*, void>)trackedObjectEnteredFinalization;
- s_initialized = true;
-
  return true;
  }
 
- private static IntPtr CreateReferenceTrackingHandleInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- // Rely on GetOrCreateReferenceTrackingMemoryInternal for state checking.
- GetOrCreateReferenceTrackingMemoryInternal(obj, out memInSizeT, out mem);
- return RuntimeImports.RhHandleAllocRefCounted(obj);
- }
-
- private static void GetOrCreateReferenceTrackingMemoryInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- if (!s_initialized)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCMarshalNotInitialized);
- }
-
- if (!obj.GetMethodTable()->IsTrackedReferenceWithFinalizer)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCTypeNoFinalizer);
- }
-
- var trackerInfo = s_objects.GetOrAdd(obj, static o => new ObjcTrackingInformation());
- trackerInfo.EnsureInitialized(obj);
- trackerInfo.GetTaggedMemory(out memInSizeT, out mem);
- }
-
- internal class ObjcTrackingInformation
- {
- // This matches the CoreCLR implementation. See
- // InteropSyncBlockInfo::m_taggedAlloc in syncblk.h .
- private const int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => RuntimeImports.RhHandleAllocRefCounted(obj);
 
- internal IntPtr _memory;
- private IntPtr _longWeakHandle;
-
- public ObjcTrackingInformation()
- {
- _memory = (IntPtr)NativeMemory.AllocZeroed(TAGGED_MEMORY_SIZE_IN_POINTERS * (nuint)IntPtr.Size);
- }
-
- public void GetTaggedMemory(out int memInSizeT, out IntPtr mem)
- {
- memInSizeT = TAGGED_MEMORY_SIZE_IN_POINTERS;
- mem = _memory;
- }
-
- public void EnsureInitialized(object o)
- {
- if (_longWeakHandle != IntPtr.Zero)
- {
- return;
- }
-
- IntPtr newHandle = RuntimeImports.RhHandleAlloc(o, GCHandleType.WeakTrackResurrection);
- if (Interlocked.CompareExchange(ref _longWeakHandle, newHandle, IntPtr.Zero) != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(newHandle);
- }
- }
-
- ~ObjcTrackingInformation()
- {
- if (_longWeakHandle != IntPtr.Zero && RuntimeImports.RhHandleGet(_longWeakHandle) != null)
- {
- GC.ReRegisterForFinalize(this);
- return;
- }
-
- if (_memory != IntPtr.Zero)
- {
- NativeMemory.Free((void*)_memory);
- _memory = IntPtr.Zero;
- }
- if (_longWeakHandle != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(_longWeakHandle);
- _longWeakHandle = IntPtr.Zero;
- }
- }
- }
+ private static bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
  }
 }

src/coreclr/vm/CMakeLists.txt

@@ -59,6 +59,7 @@ set(VM_SOURCES_DAC_AND_WKS_COMMON
  clsload.cpp
  codeman.cpp
  codeversion.cpp
+ conditionalweaktable.cpp
  contractimpl.cpp
  corhost.cpp
  crst.cpp
@@ -277,7 +278,6 @@ list(APPEND VM_HEADERS_DAC_AND_WKS_COMMON
 
 set(VM_SOURCES_DAC
  ${VM_SOURCES_DAC_AND_WKS_COMMON}
- conditionalweaktable.cpp # The usage of conditionalweaktable is only in the DAC, but we put the headers in the VM to enable validation.
 )
 
 set(VM_HEADERS_DAC

src/coreclr/vm/binder.cpp

@@ -21,7 +21,7 @@
 #include "sigbuilder.h"
 #include "configuration.h"
 #include "conditionalweaktable.h"
-#include "interoplibinterface_comwrappers.h"
+#include "interoplibinterface.h"
 #include "assemblynative.hpp"
 
 //

src/coreclr/vm/conditionalweaktable.cpp

@@ -4,11 +4,20 @@
 
 #include "conditionalweaktable.h"
 #include "gchandleutilities.h"
+
+#ifdef DACCESS_COMPILE
 #include "../debug/daccess/gcinterface.dac.h"
+#endif // DACCESS_COMPILE
 
 bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF* value)
 {
- STANDARD_VM_CONTRACT;
+ CONTRACTL
+ {
+ NOTHROW;
+ GC_NOTRIGGER;
+ MODE_ANY;
+ }
+ CONTRACTL_END;
  SUPPORTS_DAC;
  _ASSERTE(key != nullptr && value != nullptr);
 
@@ -24,11 +33,19 @@ bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF*
  int bucket = hashCode & (_buckets->GetNumComponents() - 1);
  PTR_int32_t buckets = _buckets->GetDirectPointerToNonObjectElements();
  DPTR(Entry) entries = _entries->GetDirectPointerToNonObjectElements();
+
  for (int entriesIndex = buckets[bucket]; entriesIndex != -1; entriesIndex = entries[entriesIndex].Next)
  {
- if (entries[entriesIndex].HashCode == hashCode && ObjectFromHandle(entries[entriesIndex].depHnd) == key)
+ const Entry& entry = entries[entriesIndex];
+ if (entry.HashCode == hashCode && ObjectFromHandle(entry.depHnd) == key)
  {
- *value = HndGetHandleExtraInfo(entries[entriesIndex].depHnd);
+#ifdef DACCESS_COMPILE
+ // In the DACCESS_COMPILE, the handle helper is directly accessible.
+ *value = GetDependentHandleSecondary(entry.depHnd);
+#else
+ IGCHandleManager* mgr = GCHandleUtilities::GetGCHandleManager();
+ *value = ObjectToOBJECTREF(mgr->GetDependentHandleSecondary(entry.depHnd));
+#endif // !DACCESS_COMPILE
  return true;
  }
  }

src/coreclr/vm/conditionalweaktable.h

@@ -39,22 +39,20 @@ class ConditionalWeakTableContainerObject final : public Object
  ENTRYARRAYREF _entries;
 
 public:
-#ifdef DACCESS_COMPILE
  bool TryGetValue(OBJECTREF key, OBJECTREF* value);
-#endif
 };
 
 class ConditionalWeakTableObject final : public Object
 {
  friend class CoreLibBinder;
  OBJECTREF _lock;
- VolatilePtr<ConditionalWeakTableContainerObject, CONDITIONAL_WEAK_TABLE_CONTAINER_REF> _container;
+ VolatilePtr<ConditionalWeakTableContainerObject> _container;
 public:
-#ifdef DACCESS_COMPILE
- // Currently, we only use this for access from the DAC, so we don't need to worry about
- // locking or tracking the active enumerator count.
- // If we need to use this in a context where the runtime isn't suspended, we need to add
- // the locking and tracking support.
+ // This helper can be used when the runtime is suspended (for example, DAC access
+ // or Objective-C interop callbacks that run under GC suspension). During suspension
+ // the table shape is stable since no mutations can run, so lock-free lookup is safe.
+ // If we need to use this in a context where the runtime isn't suspended, we need to
+ // add locking and active enumerator tracking support.
  template<typename TKey, typename TValue>
  bool TryGetValue(TKey key, TValue* value)
  {
@@ -67,10 +65,8 @@ class ConditionalWeakTableObject final : public Object
  {
  *value = (TValue)valueObj;
  }
-
  return found;
  }
-#endif
 };
 
 #endif // CONDITIONAL_WEAK_TABLE_H

src/coreclr/vm/corelib.h

@@ -460,6 +460,9 @@ DEFINE_FIELD_U(_buckets, GCHandleSetObject, _buckets)
 #ifdef FEATURE_OBJCMARSHAL
 DEFINE_CLASS(OBJCMARSHAL, ObjectiveC, ObjectiveCMarshal)
 DEFINE_METHOD(OBJCMARSHAL, INVOKEUNHANDLEDEXCEPTIONPROPAGATION, InvokeUnhandledExceptionPropagation, SM_PtrException_IntPtr_PtrIntPtr_PtrException_RetVoidPtr)
+DEFINE_FIELD(OBJCMARSHAL, OBJECTS, s_objects)
+DEFINE_CLASS_U(ObjectiveC, ObjectiveCMarshal+ObjcTrackingInformation, ObjcTrackingInformationObject)
+DEFINE_FIELD_U(_memory, ObjcTrackingInformationObject, _memory)
 #endif // FEATURE_OBJCMARSHAL
 
 DEFINE_CLASS_U(Interop, TypeMapLazyDictionary+CallbackContext, CallbackContext)

src/coreclr/vm/datadescriptor/datadescriptor.inc

@@ -220,9 +220,6 @@ CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCW, cdac_data<InteropSyncBlock
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, RCW, cdac_data<InteropSyncBlockInfo>::RCW)
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCF, cdac_data<InteropSyncBlockInfo>::CCF)
 #endif // FEATURE_COMINTEROP
-#ifdef FEATURE_OBJCMARSHAL
-CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, TaggedMemory, cdac_data<InteropSyncBlockInfo>::TaggedMemory)
-#endif // FEATURE_OBJCMARSHAL
 CDAC_TYPE_END(InteropSyncBlockInfo)
 
 CDAC_TYPE_BEGIN(SyncBlock)

src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeHelpers.CoreCLR.cs

@@ -844,6 +844,9 @@ internal unsafe struct MethodTable
 #if FEATURE_TYPEEQUIVALENCE
  private const uint enum_flag_HasTypeEquivalence = 0x02000000;
 #endif // FEATURE_TYPEEQUIVALENCE
+#if FEATURE_OBJCMARSHAL
+ private const uint enum_flag_IsTrackedReferenceWithFinalizer = 0x04000000;
+#endif // FEATURE_OBJCMARSHAL
  private const uint enum_flag_HasFinalizer = 0x00100000;
  private const uint enum_flag_Collectible = 0x00200000;
  private const uint enum_flag_Category_Mask = 0x000F0000;
@@ -904,6 +907,10 @@ internal unsafe struct MethodTable
  public bool HasTypeEquivalence => (Flags & enum_flag_HasTypeEquivalence) != 0;
 #endif // FEATURE_TYPEEQUIVALENCE
 
+#if FEATURE_OBJCMARSHAL
+ public bool IsTrackedReferenceWithFinalizer => (Flags & enum_flag_IsTrackedReferenceWithFinalizer) != 0;
+#endif // FEATURE_OBJCMARSHAL
+
  public bool HasFinalizer => (Flags & enum_flag_HasFinalizer) != 0;
 
  public bool IsCollectible => (Flags & enum_flag_Collectible) != 0;

src/coreclr/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.CoreCLR.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Diagnostics;
 using System.Runtime.CompilerServices;
 using System.Runtime.Versioning;
 
@@ -31,19 +32,35 @@ private static partial bool TrySetGlobalMessageSendCallback(
  private static unsafe partial bool TryInitializeReferenceTracker(
  delegate* unmanaged<void> beginEndCallback,
  delegate* unmanaged<IntPtr, int> isReferencedCallback,
- delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization);
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization,
+ ObjectHandleOnStack objectTrackingInfoTable);
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_CreateReferenceTrackingHandle")]
- private static partial IntPtr CreateReferenceTrackingHandleInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static bool TryInitializeReferenceTracker(
+ delegate* unmanaged<void> beginEndCallback,
+ delegate* unmanaged<IntPtr, int> isReferencedCallback,
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization)
+ {
+ // Make a local of the readonly field because it needs to be passed by ref to a QCall
+ // and it is marked as readonly to prevent accidental reassignment.
+ ConditionalWeakTable<object, ObjcTrackingInformation> objects = s_objects;
+ bool result = TryInitializeReferenceTracker(
+ beginEndCallback,
+ isReferencedCallback,
+ trackedObjectEnteredFinalization,
+ ObjectHandleOnStack.Create(ref objects));
+ Debug.Assert(object.ReferenceEquals(objects, s_objects));
+
+ return result;
+ }
+
+ [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_AllocateReferenceTrackingHandle")]
+ private static partial IntPtr AllocateReferenceTrackingHandle(ObjectHandleOnStack obj);
+
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => AllocateReferenceTrackingHandle(ObjectHandleOnStack.Create(ref obj));
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_GetOrCreateReferenceTrackingMemory")]
- private static partial void GetOrCreateReferenceTrackingMemoryInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static unsafe bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
 
  [UnmanagedCallersOnly]
  internal static unsafe void* InvokeUnhandledExceptionPropagation(Exception* pExceptionArg, IntPtr methodDesc, IntPtr* pContext, Exception* pException)

src/coreclr/debug/daccess/request.cpp

@@ -23,6 +23,10 @@
 #include <interoplibabi.h>
 #endif // FEATURE_COMWRAPPERS
 
+#if defined(FEATURE_OBJCMARSHAL)
+#include <interoplibinterface.h>
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 // It is unfortunate having to include this header just to get the definition of GenericModeBlock
 #include <msodw.h>
@@ -2351,7 +2355,7 @@ ClrDataAccess::GetObjectData(CLRDATA_ADDRESS addr, struct DacpObjectData *object
  objectData->ElementTypeHandle = (CLRDATA_ADDRESS)(thElem.AsTAddr());
  objectData->dwRank = mt->GetRank();
  objectData->dwNumComponents = pArrayObj->GetNumComponents ();
- objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetDataPtr (TRUE));
+ objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetGCSafeDataPtr());
  objectData->ArrayBoundsPtr = HOST_CDADDR(pArrayObj->GetBoundsPtr());
  objectData->ArrayLowerBoundsPtr = HOST_CDADDR(pArrayObj->GetLowerBoundsPtr());
  }
@@ -5393,21 +5397,26 @@ namespace
 #ifdef FEATURE_OBJCMARSHAL
  EX_TRY_ALLOW_DATATARGET_MISSING_MEMORY
  {
- PTR_SyncBlock pSyncBlk = DACGetSyncBlockFromObjectPointer(CLRDATA_ADDRESS_TO_TADDR(objAddr), target);
- if (pSyncBlk != NULL)
+ if (g_ObjectiveCTrackingInfoTable != NULL)
  {
-PTR_InteropSyncBlockInfo pInfo = pSyncBlk->GetInteropInfoNoCreate();
- if (pInfo != NULL)
+CONDITIONAL_WEAK_TABLE_REF trackingTable = (CONDITIONAL_WEAK_TABLE_REF)ObjectFromHandle(g_ObjectiveCTrackingInfoTable);
+ if (trackingTable != NULL)
  {
- CLRDATA_ADDRESS taggedMemoryLocal = PTR_CDADDR(pInfo->GetTaggedMemory());
- if (taggedMemoryLocal != NULL)
+ OBJECTREF object = OBJECTREF(CLRDATA_ADDRESS_TO_TADDR(objAddr));
+ OBJC_TRACKING_INFO_REF trackingInfo = NULL;
+ if (trackingTable->TryGetValue(object, &trackingInfo) && trackingInfo != NULL)
  {
- hasTaggedMemory = TRUE;
- if (taggedMemory)
- *taggedMemory = taggedMemoryLocal;
+ TADDR memory = (TADDR)trackingInfo->_memory;
+ if (memory != NULL)
+ {
+ hasTaggedMemory = TRUE;
+ if (taggedMemory)
+ *taggedMemory = (CLRDATA_ADDRESS)memory;
 
- if (taggedMemorySizeInBytes)
- *taggedMemorySizeInBytes = pInfo->GetTaggedMemorySizeInBytes();
+ constexpr int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ if (taggedMemorySizeInBytes)
+ *taggedMemorySizeInBytes = TAGGED_MEMORY_SIZE_IN_POINTERS * sizeof(TADDR);
+ }
  }
  }
  }

src/coreclr/inc/dacvars.h

@@ -214,6 +214,10 @@ DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_pRCWCleanupList, ::g_pRCWCleanupList)
 DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_knownQueryInterfaceImplementations, InteropLib::ABI::g_knownQueryInterfaceImplementations)
 #endif // FEATURE_COMWRAPPERS
 
+#ifdef FEATURE_OBJCMARSHAL
+DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_ObjectiveCTrackingInfoTable, ::g_ObjectiveCTrackingInfoTable)
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeLoadedBaseAddress, ::g_runtimeLoadedBaseAddress)
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeVirtualSize, ::g_runtimeVirtualSize)

src/coreclr/nativeaot/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.NativeAot.cs

@@ -11,8 +11,6 @@ namespace System.Runtime.InteropServices.ObjectiveC
  public static unsafe partial class ObjectiveCMarshal
  {
  private static readonly IntPtr[] s_ObjcMessageSendFunctions = new IntPtr[(int)MessageSendFunction.MsgSendSuperStret + 1];
- private static bool s_initialized;
- private static readonly ConditionalWeakTable<object, ObjcTrackingInformation> s_objects = new();
  private static delegate* unmanaged[SuppressGCTransition]<void*, int> s_IsTrackedReferenceCallback;
  private static delegate* unmanaged[SuppressGCTransition]<void*, void> s_OnEnteredFinalizerQueueCallback;
 
@@ -116,94 +114,13 @@ private static bool TryInitializeReferenceTracker(
 
  s_IsTrackedReferenceCallback = (delegate* unmanaged[SuppressGCTransition]<void*, int>)isReferencedCallback;
  s_OnEnteredFinalizerQueueCallback = (delegate* unmanaged[SuppressGCTransition]<void*, void>)trackedObjectEnteredFinalization;
- s_initialized = true;
-
  return true;
  }
 
- private static IntPtr CreateReferenceTrackingHandleInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- // Rely on GetOrCreateReferenceTrackingMemoryInternal for state checking.
- GetOrCreateReferenceTrackingMemoryInternal(obj, out memInSizeT, out mem);
- return RuntimeImports.RhHandleAllocRefCounted(obj);
- }
-
- private static void GetOrCreateReferenceTrackingMemoryInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- if (!s_initialized)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCMarshalNotInitialized);
- }
-
- if (!obj.GetMethodTable()->IsTrackedReferenceWithFinalizer)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCTypeNoFinalizer);
- }
-
- var trackerInfo = s_objects.GetOrAdd(obj, static o => new ObjcTrackingInformation());
- trackerInfo.EnsureInitialized(obj);
- trackerInfo.GetTaggedMemory(out memInSizeT, out mem);
- }
-
- internal class ObjcTrackingInformation
- {
- // This matches the CoreCLR implementation. See
- // InteropSyncBlockInfo::m_taggedAlloc in syncblk.h .
- private const int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => RuntimeImports.RhHandleAllocRefCounted(obj);
 
- internal IntPtr _memory;
- private IntPtr _longWeakHandle;
-
- public ObjcTrackingInformation()
- {
- _memory = (IntPtr)NativeMemory.AllocZeroed(TAGGED_MEMORY_SIZE_IN_POINTERS * (nuint)IntPtr.Size);
- }
-
- public void GetTaggedMemory(out int memInSizeT, out IntPtr mem)
- {
- memInSizeT = TAGGED_MEMORY_SIZE_IN_POINTERS;
- mem = _memory;
- }
-
- public void EnsureInitialized(object o)
- {
- if (_longWeakHandle != IntPtr.Zero)
- {
- return;
- }
-
- IntPtr newHandle = RuntimeImports.RhHandleAlloc(o, GCHandleType.WeakTrackResurrection);
- if (Interlocked.CompareExchange(ref _longWeakHandle, newHandle, IntPtr.Zero) != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(newHandle);
- }
- }
-
- ~ObjcTrackingInformation()
- {
- if (_longWeakHandle != IntPtr.Zero && RuntimeImports.RhHandleGet(_longWeakHandle) != null)
- {
- GC.ReRegisterForFinalize(this);
- return;
- }
-
- if (_memory != IntPtr.Zero)
- {
- NativeMemory.Free((void*)_memory);
- _memory = IntPtr.Zero;
- }
- if (_longWeakHandle != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(_longWeakHandle);
- _longWeakHandle = IntPtr.Zero;
- }
- }
- }
+ private static bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
  }
 }

src/coreclr/vm/CMakeLists.txt

@@ -59,6 +59,7 @@ set(VM_SOURCES_DAC_AND_WKS_COMMON
  clsload.cpp
  codeman.cpp
  codeversion.cpp
+ conditionalweaktable.cpp
  contractimpl.cpp
  corhost.cpp
  crst.cpp
@@ -277,7 +278,6 @@ list(APPEND VM_HEADERS_DAC_AND_WKS_COMMON
 
 set(VM_SOURCES_DAC
  ${VM_SOURCES_DAC_AND_WKS_COMMON}
- conditionalweaktable.cpp # The usage of conditionalweaktable is only in the DAC, but we put the headers in the VM to enable validation.
 )
 
 set(VM_HEADERS_DAC

src/coreclr/vm/binder.cpp

@@ -21,7 +21,7 @@
 #include "sigbuilder.h"
 #include "configuration.h"
 #include "conditionalweaktable.h"
-#include "interoplibinterface_comwrappers.h"
+#include "interoplibinterface.h"
 #include "assemblynative.hpp"
 
 //

src/coreclr/vm/conditionalweaktable.cpp

@@ -4,11 +4,20 @@
 
 #include "conditionalweaktable.h"
 #include "gchandleutilities.h"
+
+#ifdef DACCESS_COMPILE
 #include "../debug/daccess/gcinterface.dac.h"
+#endif // DACCESS_COMPILE
 
 bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF* value)
 {
- STANDARD_VM_CONTRACT;
+ CONTRACTL
+ {
+ NOTHROW;
+ GC_NOTRIGGER;
+ MODE_ANY;
+ }
+ CONTRACTL_END;
  SUPPORTS_DAC;
  _ASSERTE(key != nullptr && value != nullptr);
 
@@ -24,11 +33,19 @@ bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF*
  int bucket = hashCode & (_buckets->GetNumComponents() - 1);
  PTR_int32_t buckets = _buckets->GetDirectPointerToNonObjectElements();
  DPTR(Entry) entries = _entries->GetDirectPointerToNonObjectElements();
+
  for (int entriesIndex = buckets[bucket]; entriesIndex != -1; entriesIndex = entries[entriesIndex].Next)
  {
- if (entries[entriesIndex].HashCode == hashCode && ObjectFromHandle(entries[entriesIndex].depHnd) == key)
+ const Entry& entry = entries[entriesIndex];
+ if (entry.HashCode == hashCode && ObjectFromHandle(entry.depHnd) == key)
  {
- *value = HndGetHandleExtraInfo(entries[entriesIndex].depHnd);
+#ifdef DACCESS_COMPILE
+ // In the DACCESS_COMPILE, the handle helper is directly accessible.
+ *value = GetDependentHandleSecondary(entry.depHnd);
+#else
+ IGCHandleManager* mgr = GCHandleUtilities::GetGCHandleManager();
+ *value = ObjectToOBJECTREF(mgr->GetDependentHandleSecondary(entry.depHnd));
+#endif // !DACCESS_COMPILE
  return true;
  }
  }

src/coreclr/vm/conditionalweaktable.h

@@ -39,22 +39,20 @@ class ConditionalWeakTableContainerObject final : public Object
  ENTRYARRAYREF _entries;
 
 public:
-#ifdef DACCESS_COMPILE
  bool TryGetValue(OBJECTREF key, OBJECTREF* value);
-#endif
 };
 
 class ConditionalWeakTableObject final : public Object
 {
  friend class CoreLibBinder;
  OBJECTREF _lock;
- VolatilePtr<ConditionalWeakTableContainerObject, CONDITIONAL_WEAK_TABLE_CONTAINER_REF> _container;
+ VolatilePtr<ConditionalWeakTableContainerObject> _container;
 public:
-#ifdef DACCESS_COMPILE
- // Currently, we only use this for access from the DAC, so we don't need to worry about
- // locking or tracking the active enumerator count.
- // If we need to use this in a context where the runtime isn't suspended, we need to add
- // the locking and tracking support.
+ // This helper can be used when the runtime is suspended (for example, DAC access
+ // or Objective-C interop callbacks that run under GC suspension). During suspension
+ // the table shape is stable since no mutations can run, so lock-free lookup is safe.
+ // If we need to use this in a context where the runtime isn't suspended, we need to
+ // add locking and active enumerator tracking support.
  template<typename TKey, typename TValue>
  bool TryGetValue(TKey key, TValue* value)
  {
@@ -67,10 +65,8 @@ class ConditionalWeakTableObject final : public Object
  {
  *value = (TValue)valueObj;
  }
-
  return found;
  }
-#endif
 };
 
 #endif // CONDITIONAL_WEAK_TABLE_H

src/coreclr/vm/corelib.h

@@ -460,6 +460,9 @@ DEFINE_FIELD_U(_buckets, GCHandleSetObject, _buckets)
 #ifdef FEATURE_OBJCMARSHAL
 DEFINE_CLASS(OBJCMARSHAL, ObjectiveC, ObjectiveCMarshal)
 DEFINE_METHOD(OBJCMARSHAL, INVOKEUNHANDLEDEXCEPTIONPROPAGATION, InvokeUnhandledExceptionPropagation, SM_PtrException_IntPtr_PtrIntPtr_PtrException_RetVoidPtr)
+DEFINE_FIELD(OBJCMARSHAL, OBJECTS, s_objects)
+DEFINE_CLASS_U(ObjectiveC, ObjectiveCMarshal+ObjcTrackingInformation, ObjcTrackingInformationObject)
+DEFINE_FIELD_U(_memory, ObjcTrackingInformationObject, _memory)
 #endif // FEATURE_OBJCMARSHAL
 
 DEFINE_CLASS_U(Interop, TypeMapLazyDictionary+CallbackContext, CallbackContext)

src/coreclr/vm/datadescriptor/datadescriptor.inc

@@ -220,9 +220,6 @@ CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCW, cdac_data<InteropSyncBlock
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, RCW, cdac_data<InteropSyncBlockInfo>::RCW)
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCF, cdac_data<InteropSyncBlockInfo>::CCF)
 #endif // FEATURE_COMINTEROP
-#ifdef FEATURE_OBJCMARSHAL
-CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, TaggedMemory, cdac_data<InteropSyncBlockInfo>::TaggedMemory)
-#endif // FEATURE_OBJCMARSHAL
 CDAC_TYPE_END(InteropSyncBlockInfo)
 
 CDAC_TYPE_BEGIN(SyncBlock)

src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeHelpers.CoreCLR.cs

@@ -844,6 +844,9 @@ internal unsafe struct MethodTable
 #if FEATURE_TYPEEQUIVALENCE
  private const uint enum_flag_HasTypeEquivalence = 0x02000000;
 #endif // FEATURE_TYPEEQUIVALENCE
+#if FEATURE_OBJCMARSHAL
+ private const uint enum_flag_IsTrackedReferenceWithFinalizer = 0x04000000;
+#endif // FEATURE_OBJCMARSHAL
  private const uint enum_flag_HasFinalizer = 0x00100000;
  private const uint enum_flag_Collectible = 0x00200000;
  private const uint enum_flag_Category_Mask = 0x000F0000;
@@ -904,6 +907,10 @@ internal unsafe struct MethodTable
  public bool HasTypeEquivalence => (Flags & enum_flag_HasTypeEquivalence) != 0;
 #endif // FEATURE_TYPEEQUIVALENCE
 
+#if FEATURE_OBJCMARSHAL
+ public bool IsTrackedReferenceWithFinalizer => (Flags & enum_flag_IsTrackedReferenceWithFinalizer) != 0;
+#endif // FEATURE_OBJCMARSHAL
+
  public bool HasFinalizer => (Flags & enum_flag_HasFinalizer) != 0;
 
  public bool IsCollectible => (Flags & enum_flag_Collectible) != 0;

src/coreclr/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.CoreCLR.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Diagnostics;
 using System.Runtime.CompilerServices;
 using System.Runtime.Versioning;
 
@@ -31,19 +32,35 @@ private static partial bool TrySetGlobalMessageSendCallback(
  private static unsafe partial bool TryInitializeReferenceTracker(
  delegate* unmanaged<void> beginEndCallback,
  delegate* unmanaged<IntPtr, int> isReferencedCallback,
- delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization);
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization,
+ ObjectHandleOnStack objectTrackingInfoTable);
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_CreateReferenceTrackingHandle")]
- private static partial IntPtr CreateReferenceTrackingHandleInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static bool TryInitializeReferenceTracker(
+ delegate* unmanaged<void> beginEndCallback,
+ delegate* unmanaged<IntPtr, int> isReferencedCallback,
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization)
+ {
+ // Make a local of the readonly field because it needs to be passed by ref to a QCall
+ // and it is marked as readonly to prevent accidental reassignment.
+ ConditionalWeakTable<object, ObjcTrackingInformation> objects = s_objects;
+ bool result = TryInitializeReferenceTracker(
+ beginEndCallback,
+ isReferencedCallback,
+ trackedObjectEnteredFinalization,
+ ObjectHandleOnStack.Create(ref objects));
+ Debug.Assert(object.ReferenceEquals(objects, s_objects));
+
+ return result;
+ }
+
+ [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_AllocateReferenceTrackingHandle")]
+ private static partial IntPtr AllocateReferenceTrackingHandle(ObjectHandleOnStack obj);
+
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => AllocateReferenceTrackingHandle(ObjectHandleOnStack.Create(ref obj));
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_GetOrCreateReferenceTrackingMemory")]
- private static partial void GetOrCreateReferenceTrackingMemoryInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static unsafe bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
 
  [UnmanagedCallersOnly]
  internal static unsafe void* InvokeUnhandledExceptionPropagation(Exception* pExceptionArg, IntPtr methodDesc, IntPtr* pContext, Exception* pException)

src/coreclr/debug/daccess/request.cpp

@@ -23,6 +23,10 @@
 #include <interoplibabi.h>
 #endif // FEATURE_COMWRAPPERS
 
+#if defined(FEATURE_OBJCMARSHAL)
+#include <interoplibinterface.h>
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 // It is unfortunate having to include this header just to get the definition of GenericModeBlock
 #include <msodw.h>
@@ -2351,7 +2355,7 @@ ClrDataAccess::GetObjectData(CLRDATA_ADDRESS addr, struct DacpObjectData *object
  objectData->ElementTypeHandle = (CLRDATA_ADDRESS)(thElem.AsTAddr());
  objectData->dwRank = mt->GetRank();
  objectData->dwNumComponents = pArrayObj->GetNumComponents ();
- objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetDataPtr (TRUE));
+ objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetGCSafeDataPtr());
  objectData->ArrayBoundsPtr = HOST_CDADDR(pArrayObj->GetBoundsPtr());
  objectData->ArrayLowerBoundsPtr = HOST_CDADDR(pArrayObj->GetLowerBoundsPtr());
  }
@@ -5393,21 +5397,26 @@ namespace
 #ifdef FEATURE_OBJCMARSHAL
  EX_TRY_ALLOW_DATATARGET_MISSING_MEMORY
  {
- PTR_SyncBlock pSyncBlk = DACGetSyncBlockFromObjectPointer(CLRDATA_ADDRESS_TO_TADDR(objAddr), target);
- if (pSyncBlk != NULL)
+ if (g_ObjectiveCTrackingInfoTable != NULL)
  {
-PTR_InteropSyncBlockInfo pInfo = pSyncBlk->GetInteropInfoNoCreate();
- if (pInfo != NULL)
+CONDITIONAL_WEAK_TABLE_REF trackingTable = (CONDITIONAL_WEAK_TABLE_REF)ObjectFromHandle(g_ObjectiveCTrackingInfoTable);
+ if (trackingTable != NULL)
  {
- CLRDATA_ADDRESS taggedMemoryLocal = PTR_CDADDR(pInfo->GetTaggedMemory());
- if (taggedMemoryLocal != NULL)
+ OBJECTREF object = OBJECTREF(CLRDATA_ADDRESS_TO_TADDR(objAddr));
+ OBJC_TRACKING_INFO_REF trackingInfo = NULL;
+ if (trackingTable->TryGetValue(object, &trackingInfo) && trackingInfo != NULL)
  {
- hasTaggedMemory = TRUE;
- if (taggedMemory)
- *taggedMemory = taggedMemoryLocal;
+ TADDR memory = (TADDR)trackingInfo->_memory;
+ if (memory != NULL)
+ {
+ hasTaggedMemory = TRUE;
+ if (taggedMemory)
+ *taggedMemory = (CLRDATA_ADDRESS)memory;
 
- if (taggedMemorySizeInBytes)
- *taggedMemorySizeInBytes = pInfo->GetTaggedMemorySizeInBytes();
+ constexpr int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ if (taggedMemorySizeInBytes)
+ *taggedMemorySizeInBytes = TAGGED_MEMORY_SIZE_IN_POINTERS * sizeof(TADDR);
+ }
  }
  }
  }

src/coreclr/inc/dacvars.h

@@ -214,6 +214,10 @@ DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_pRCWCleanupList, ::g_pRCWCleanupList)
 DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_knownQueryInterfaceImplementations, InteropLib::ABI::g_knownQueryInterfaceImplementations)
 #endif // FEATURE_COMWRAPPERS
 
+#ifdef FEATURE_OBJCMARSHAL
+DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_ObjectiveCTrackingInfoTable, ::g_ObjectiveCTrackingInfoTable)
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeLoadedBaseAddress, ::g_runtimeLoadedBaseAddress)
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeVirtualSize, ::g_runtimeVirtualSize)

src/coreclr/nativeaot/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.NativeAot.cs

@@ -11,8 +11,6 @@ namespace System.Runtime.InteropServices.ObjectiveC
  public static unsafe partial class ObjectiveCMarshal
  {
  private static readonly IntPtr[] s_ObjcMessageSendFunctions = new IntPtr[(int)MessageSendFunction.MsgSendSuperStret + 1];
- private static bool s_initialized;
- private static readonly ConditionalWeakTable<object, ObjcTrackingInformation> s_objects = new();
  private static delegate* unmanaged[SuppressGCTransition]<void*, int> s_IsTrackedReferenceCallback;
  private static delegate* unmanaged[SuppressGCTransition]<void*, void> s_OnEnteredFinalizerQueueCallback;
 
@@ -116,94 +114,13 @@ private static bool TryInitializeReferenceTracker(
 
  s_IsTrackedReferenceCallback = (delegate* unmanaged[SuppressGCTransition]<void*, int>)isReferencedCallback;
  s_OnEnteredFinalizerQueueCallback = (delegate* unmanaged[SuppressGCTransition]<void*, void>)trackedObjectEnteredFinalization;
- s_initialized = true;
-
  return true;
  }
 
- private static IntPtr CreateReferenceTrackingHandleInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- // Rely on GetOrCreateReferenceTrackingMemoryInternal for state checking.
- GetOrCreateReferenceTrackingMemoryInternal(obj, out memInSizeT, out mem);
- return RuntimeImports.RhHandleAllocRefCounted(obj);
- }
-
- private static void GetOrCreateReferenceTrackingMemoryInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- if (!s_initialized)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCMarshalNotInitialized);
- }
-
- if (!obj.GetMethodTable()->IsTrackedReferenceWithFinalizer)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCTypeNoFinalizer);
- }
-
- var trackerInfo = s_objects.GetOrAdd(obj, static o => new ObjcTrackingInformation());
- trackerInfo.EnsureInitialized(obj);
- trackerInfo.GetTaggedMemory(out memInSizeT, out mem);
- }
-
- internal class ObjcTrackingInformation
- {
- // This matches the CoreCLR implementation. See
- // InteropSyncBlockInfo::m_taggedAlloc in syncblk.h .
- private const int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => RuntimeImports.RhHandleAllocRefCounted(obj);
 
- internal IntPtr _memory;
- private IntPtr _longWeakHandle;
-
- public ObjcTrackingInformation()
- {
- _memory = (IntPtr)NativeMemory.AllocZeroed(TAGGED_MEMORY_SIZE_IN_POINTERS * (nuint)IntPtr.Size);
- }
-
- public void GetTaggedMemory(out int memInSizeT, out IntPtr mem)
- {
- memInSizeT = TAGGED_MEMORY_SIZE_IN_POINTERS;
- mem = _memory;
- }
-
- public void EnsureInitialized(object o)
- {
- if (_longWeakHandle != IntPtr.Zero)
- {
- return;
- }
-
- IntPtr newHandle = RuntimeImports.RhHandleAlloc(o, GCHandleType.WeakTrackResurrection);
- if (Interlocked.CompareExchange(ref _longWeakHandle, newHandle, IntPtr.Zero) != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(newHandle);
- }
- }
-
- ~ObjcTrackingInformation()
- {
- if (_longWeakHandle != IntPtr.Zero && RuntimeImports.RhHandleGet(_longWeakHandle) != null)
- {
- GC.ReRegisterForFinalize(this);
- return;
- }
-
- if (_memory != IntPtr.Zero)
- {
- NativeMemory.Free((void*)_memory);
- _memory = IntPtr.Zero;
- }
- if (_longWeakHandle != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(_longWeakHandle);
- _longWeakHandle = IntPtr.Zero;
- }
- }
- }
+ private static bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
  }
 }

src/coreclr/vm/CMakeLists.txt

@@ -59,6 +59,7 @@ set(VM_SOURCES_DAC_AND_WKS_COMMON
  clsload.cpp
  codeman.cpp
  codeversion.cpp
+ conditionalweaktable.cpp
  contractimpl.cpp
  corhost.cpp
  crst.cpp
@@ -277,7 +278,6 @@ list(APPEND VM_HEADERS_DAC_AND_WKS_COMMON
 
 set(VM_SOURCES_DAC
  ${VM_SOURCES_DAC_AND_WKS_COMMON}
- conditionalweaktable.cpp # The usage of conditionalweaktable is only in the DAC, but we put the headers in the VM to enable validation.
 )
 
 set(VM_HEADERS_DAC

src/coreclr/vm/binder.cpp

@@ -21,7 +21,7 @@
 #include "sigbuilder.h"
 #include "configuration.h"
 #include "conditionalweaktable.h"
-#include "interoplibinterface_comwrappers.h"
+#include "interoplibinterface.h"
 #include "assemblynative.hpp"
 
 //

src/coreclr/vm/conditionalweaktable.cpp

@@ -4,11 +4,20 @@
 
 #include "conditionalweaktable.h"
 #include "gchandleutilities.h"
+
+#ifdef DACCESS_COMPILE
 #include "../debug/daccess/gcinterface.dac.h"
+#endif // DACCESS_COMPILE
 
 bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF* value)
 {
- STANDARD_VM_CONTRACT;
+ CONTRACTL
+ {
+ NOTHROW;
+ GC_NOTRIGGER;
+ MODE_ANY;
+ }
+ CONTRACTL_END;
  SUPPORTS_DAC;
  _ASSERTE(key != nullptr && value != nullptr);
 
@@ -24,11 +33,19 @@ bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF*
  int bucket = hashCode & (_buckets->GetNumComponents() - 1);
  PTR_int32_t buckets = _buckets->GetDirectPointerToNonObjectElements();
  DPTR(Entry) entries = _entries->GetDirectPointerToNonObjectElements();
+
  for (int entriesIndex = buckets[bucket]; entriesIndex != -1; entriesIndex = entries[entriesIndex].Next)
  {
- if (entries[entriesIndex].HashCode == hashCode && ObjectFromHandle(entries[entriesIndex].depHnd) == key)
+ const Entry& entry = entries[entriesIndex];
+ if (entry.HashCode == hashCode && ObjectFromHandle(entry.depHnd) == key)
  {
- *value = HndGetHandleExtraInfo(entries[entriesIndex].depHnd);
+#ifdef DACCESS_COMPILE
+ // In the DACCESS_COMPILE, the handle helper is directly accessible.
+ *value = GetDependentHandleSecondary(entry.depHnd);
+#else
+ IGCHandleManager* mgr = GCHandleUtilities::GetGCHandleManager();
+ *value = ObjectToOBJECTREF(mgr->GetDependentHandleSecondary(entry.depHnd));
+#endif // !DACCESS_COMPILE
  return true;
  }
  }

src/coreclr/vm/conditionalweaktable.h

@@ -39,22 +39,20 @@ class ConditionalWeakTableContainerObject final : public Object
  ENTRYARRAYREF _entries;
 
 public:
-#ifdef DACCESS_COMPILE
  bool TryGetValue(OBJECTREF key, OBJECTREF* value);
-#endif
 };
 
 class ConditionalWeakTableObject final : public Object
 {
  friend class CoreLibBinder;
  OBJECTREF _lock;
- VolatilePtr<ConditionalWeakTableContainerObject, CONDITIONAL_WEAK_TABLE_CONTAINER_REF> _container;
+ VolatilePtr<ConditionalWeakTableContainerObject> _container;
 public:
-#ifdef DACCESS_COMPILE
- // Currently, we only use this for access from the DAC, so we don't need to worry about
- // locking or tracking the active enumerator count.
- // If we need to use this in a context where the runtime isn't suspended, we need to add
- // the locking and tracking support.
+ // This helper can be used when the runtime is suspended (for example, DAC access
+ // or Objective-C interop callbacks that run under GC suspension). During suspension
+ // the table shape is stable since no mutations can run, so lock-free lookup is safe.
+ // If we need to use this in a context where the runtime isn't suspended, we need to
+ // add locking and active enumerator tracking support.
  template<typename TKey, typename TValue>
  bool TryGetValue(TKey key, TValue* value)
  {
@@ -67,10 +65,8 @@ class ConditionalWeakTableObject final : public Object
  {
  *value = (TValue)valueObj;
  }
-
  return found;
  }
-#endif
 };
 
 #endif // CONDITIONAL_WEAK_TABLE_H

src/coreclr/vm/corelib.h

@@ -460,6 +460,9 @@ DEFINE_FIELD_U(_buckets, GCHandleSetObject, _buckets)
 #ifdef FEATURE_OBJCMARSHAL
 DEFINE_CLASS(OBJCMARSHAL, ObjectiveC, ObjectiveCMarshal)
 DEFINE_METHOD(OBJCMARSHAL, INVOKEUNHANDLEDEXCEPTIONPROPAGATION, InvokeUnhandledExceptionPropagation, SM_PtrException_IntPtr_PtrIntPtr_PtrException_RetVoidPtr)
+DEFINE_FIELD(OBJCMARSHAL, OBJECTS, s_objects)
+DEFINE_CLASS_U(ObjectiveC, ObjectiveCMarshal+ObjcTrackingInformation, ObjcTrackingInformationObject)
+DEFINE_FIELD_U(_memory, ObjcTrackingInformationObject, _memory)
 #endif // FEATURE_OBJCMARSHAL
 
 DEFINE_CLASS_U(Interop, TypeMapLazyDictionary+CallbackContext, CallbackContext)

src/coreclr/vm/datadescriptor/datadescriptor.inc

@@ -220,9 +220,6 @@ CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCW, cdac_data<InteropSyncBlock
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, RCW, cdac_data<InteropSyncBlockInfo>::RCW)
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCF, cdac_data<InteropSyncBlockInfo>::CCF)
 #endif // FEATURE_COMINTEROP
-#ifdef FEATURE_OBJCMARSHAL
-CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, TaggedMemory, cdac_data<InteropSyncBlockInfo>::TaggedMemory)
-#endif // FEATURE_OBJCMARSHAL
 CDAC_TYPE_END(InteropSyncBlockInfo)
 
 CDAC_TYPE_BEGIN(SyncBlock)

src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeHelpers.CoreCLR.cs

@@ -844,6 +844,9 @@ internal unsafe struct MethodTable
 #if FEATURE_TYPEEQUIVALENCE
  private const uint enum_flag_HasTypeEquivalence = 0x02000000;
 #endif // FEATURE_TYPEEQUIVALENCE
+#if FEATURE_OBJCMARSHAL
+ private const uint enum_flag_IsTrackedReferenceWithFinalizer = 0x04000000;
+#endif // FEATURE_OBJCMARSHAL
  private const uint enum_flag_HasFinalizer = 0x00100000;
  private const uint enum_flag_Collectible = 0x00200000;
  private const uint enum_flag_Category_Mask = 0x000F0000;
@@ -904,6 +907,10 @@ internal unsafe struct MethodTable
  public bool HasTypeEquivalence => (Flags & enum_flag_HasTypeEquivalence) != 0;
 #endif // FEATURE_TYPEEQUIVALENCE
 
+#if FEATURE_OBJCMARSHAL
+ public bool IsTrackedReferenceWithFinalizer => (Flags & enum_flag_IsTrackedReferenceWithFinalizer) != 0;
+#endif // FEATURE_OBJCMARSHAL
+
  public bool HasFinalizer => (Flags & enum_flag_HasFinalizer) != 0;
 
  public bool IsCollectible => (Flags & enum_flag_Collectible) != 0;

src/coreclr/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.CoreCLR.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Diagnostics;
 using System.Runtime.CompilerServices;
 using System.Runtime.Versioning;
 
@@ -31,19 +32,35 @@ private static partial bool TrySetGlobalMessageSendCallback(
  private static unsafe partial bool TryInitializeReferenceTracker(
  delegate* unmanaged<void> beginEndCallback,
  delegate* unmanaged<IntPtr, int> isReferencedCallback,
- delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization);
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization,
+ ObjectHandleOnStack objectTrackingInfoTable);
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_CreateReferenceTrackingHandle")]
- private static partial IntPtr CreateReferenceTrackingHandleInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static bool TryInitializeReferenceTracker(
+ delegate* unmanaged<void> beginEndCallback,
+ delegate* unmanaged<IntPtr, int> isReferencedCallback,
+ delegate* unmanaged<IntPtr, void> trackedObjectEnteredFinalization)
+ {
+ // Make a local of the readonly field because it needs to be passed by ref to a QCall
+ // and it is marked as readonly to prevent accidental reassignment.
+ ConditionalWeakTable<object, ObjcTrackingInformation> objects = s_objects;
+ bool result = TryInitializeReferenceTracker(
+ beginEndCallback,
+ isReferencedCallback,
+ trackedObjectEnteredFinalization,
+ ObjectHandleOnStack.Create(ref objects));
+ Debug.Assert(object.ReferenceEquals(objects, s_objects));
+
+ return result;
+ }
+
+ [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_AllocateReferenceTrackingHandle")]
+ private static partial IntPtr AllocateReferenceTrackingHandle(ObjectHandleOnStack obj);
+
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => AllocateReferenceTrackingHandle(ObjectHandleOnStack.Create(ref obj));
 
- [LibraryImport(RuntimeHelpers.QCall, EntryPoint = "ObjCMarshal_GetOrCreateReferenceTrackingMemory")]
- private static partial void GetOrCreateReferenceTrackingMemoryInternal(
- ObjectHandleOnStack obj,
- out int memInSizeT,
- out IntPtr mem);
+ private static unsafe bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
 
  [UnmanagedCallersOnly]
  internal static unsafe void* InvokeUnhandledExceptionPropagation(Exception* pExceptionArg, IntPtr methodDesc, IntPtr* pContext, Exception* pException)

src/coreclr/debug/daccess/request.cpp

@@ -23,6 +23,10 @@
 #include <interoplibabi.h>
 #endif // FEATURE_COMWRAPPERS
 
+#if defined(FEATURE_OBJCMARSHAL)
+#include <interoplibinterface.h>
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 // It is unfortunate having to include this header just to get the definition of GenericModeBlock
 #include <msodw.h>
@@ -2351,7 +2355,7 @@ ClrDataAccess::GetObjectData(CLRDATA_ADDRESS addr, struct DacpObjectData *object
  objectData->ElementTypeHandle = (CLRDATA_ADDRESS)(thElem.AsTAddr());
  objectData->dwRank = mt->GetRank();
  objectData->dwNumComponents = pArrayObj->GetNumComponents ();
- objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetDataPtr (TRUE));
+ objectData->ArrayDataPtr = PTR_CDADDR(pArrayObj->GetGCSafeDataPtr());
  objectData->ArrayBoundsPtr = HOST_CDADDR(pArrayObj->GetBoundsPtr());
  objectData->ArrayLowerBoundsPtr = HOST_CDADDR(pArrayObj->GetLowerBoundsPtr());
  }
@@ -5393,21 +5397,26 @@ namespace
 #ifdef FEATURE_OBJCMARSHAL
  EX_TRY_ALLOW_DATATARGET_MISSING_MEMORY
  {
- PTR_SyncBlock pSyncBlk = DACGetSyncBlockFromObjectPointer(CLRDATA_ADDRESS_TO_TADDR(objAddr), target);
- if (pSyncBlk != NULL)
+ if (g_ObjectiveCTrackingInfoTable != NULL)
  {
-PTR_InteropSyncBlockInfo pInfo = pSyncBlk->GetInteropInfoNoCreate();
- if (pInfo != NULL)
+CONDITIONAL_WEAK_TABLE_REF trackingTable = (CONDITIONAL_WEAK_TABLE_REF)ObjectFromHandle(g_ObjectiveCTrackingInfoTable);
+ if (trackingTable != NULL)
  {
- CLRDATA_ADDRESS taggedMemoryLocal = PTR_CDADDR(pInfo->GetTaggedMemory());
- if (taggedMemoryLocal != NULL)
+ OBJECTREF object = OBJECTREF(CLRDATA_ADDRESS_TO_TADDR(objAddr));
+ OBJC_TRACKING_INFO_REF trackingInfo = NULL;
+ if (trackingTable->TryGetValue(object, &trackingInfo) && trackingInfo != NULL)
  {
- hasTaggedMemory = TRUE;
- if (taggedMemory)
- *taggedMemory = taggedMemoryLocal;
+ TADDR memory = (TADDR)trackingInfo->_memory;
+ if (memory != NULL)
+ {
+ hasTaggedMemory = TRUE;
+ if (taggedMemory)
+ *taggedMemory = (CLRDATA_ADDRESS)memory;
 
- if (taggedMemorySizeInBytes)
- *taggedMemorySizeInBytes = pInfo->GetTaggedMemorySizeInBytes();
+ constexpr int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ if (taggedMemorySizeInBytes)
+ *taggedMemorySizeInBytes = TAGGED_MEMORY_SIZE_IN_POINTERS * sizeof(TADDR);
+ }
  }
  }
  }

src/coreclr/inc/dacvars.h

@@ -214,6 +214,10 @@ DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_pRCWCleanupList, ::g_pRCWCleanupList)
 DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_knownQueryInterfaceImplementations, InteropLib::ABI::g_knownQueryInterfaceImplementations)
 #endif // FEATURE_COMWRAPPERS
 
+#ifdef FEATURE_OBJCMARSHAL
+DEFINE_DACVAR(UNKNOWN_POINTER_TYPE, dac__g_ObjectiveCTrackingInfoTable, ::g_ObjectiveCTrackingInfoTable)
+#endif // FEATURE_OBJCMARSHAL
+
 #ifndef TARGET_UNIX
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeLoadedBaseAddress, ::g_runtimeLoadedBaseAddress)
 DEFINE_DACVAR(SIZE_T, dac__g_runtimeVirtualSize, ::g_runtimeVirtualSize)

src/coreclr/nativeaot/System.Private.CoreLib/src/System/Runtime/InteropServices/ObjectiveCMarshal.NativeAot.cs

@@ -11,8 +11,6 @@ namespace System.Runtime.InteropServices.ObjectiveC
  public static unsafe partial class ObjectiveCMarshal
  {
  private static readonly IntPtr[] s_ObjcMessageSendFunctions = new IntPtr[(int)MessageSendFunction.MsgSendSuperStret + 1];
- private static bool s_initialized;
- private static readonly ConditionalWeakTable<object, ObjcTrackingInformation> s_objects = new();
  private static delegate* unmanaged[SuppressGCTransition]<void*, int> s_IsTrackedReferenceCallback;
  private static delegate* unmanaged[SuppressGCTransition]<void*, void> s_OnEnteredFinalizerQueueCallback;
 
@@ -116,94 +114,13 @@ private static bool TryInitializeReferenceTracker(
 
  s_IsTrackedReferenceCallback = (delegate* unmanaged[SuppressGCTransition]<void*, int>)isReferencedCallback;
  s_OnEnteredFinalizerQueueCallback = (delegate* unmanaged[SuppressGCTransition]<void*, void>)trackedObjectEnteredFinalization;
- s_initialized = true;
-
  return true;
  }
 
- private static IntPtr CreateReferenceTrackingHandleInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- // Rely on GetOrCreateReferenceTrackingMemoryInternal for state checking.
- GetOrCreateReferenceTrackingMemoryInternal(obj, out memInSizeT, out mem);
- return RuntimeImports.RhHandleAllocRefCounted(obj);
- }
-
- private static void GetOrCreateReferenceTrackingMemoryInternal(
- object obj,
- out int memInSizeT,
- out IntPtr mem)
- {
- if (!s_initialized)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCMarshalNotInitialized);
- }
-
- if (!obj.GetMethodTable()->IsTrackedReferenceWithFinalizer)
- {
- throw new InvalidOperationException(SR.InvalidOperation_ObjectiveCTypeNoFinalizer);
- }
-
- var trackerInfo = s_objects.GetOrAdd(obj, static o => new ObjcTrackingInformation());
- trackerInfo.EnsureInitialized(obj);
- trackerInfo.GetTaggedMemory(out memInSizeT, out mem);
- }
-
- internal class ObjcTrackingInformation
- {
- // This matches the CoreCLR implementation. See
- // InteropSyncBlockInfo::m_taggedAlloc in syncblk.h .
- private const int TAGGED_MEMORY_SIZE_IN_POINTERS = 2;
+ private static IntPtr AllocateReferenceTrackingHandle(object obj)
+ => RuntimeImports.RhHandleAllocRefCounted(obj);
 
- internal IntPtr _memory;
- private IntPtr _longWeakHandle;
-
- public ObjcTrackingInformation()
- {
- _memory = (IntPtr)NativeMemory.AllocZeroed(TAGGED_MEMORY_SIZE_IN_POINTERS * (nuint)IntPtr.Size);
- }
-
- public void GetTaggedMemory(out int memInSizeT, out IntPtr mem)
- {
- memInSizeT = TAGGED_MEMORY_SIZE_IN_POINTERS;
- mem = _memory;
- }
-
- public void EnsureInitialized(object o)
- {
- if (_longWeakHandle != IntPtr.Zero)
- {
- return;
- }
-
- IntPtr newHandle = RuntimeImports.RhHandleAlloc(o, GCHandleType.WeakTrackResurrection);
- if (Interlocked.CompareExchange(ref _longWeakHandle, newHandle, IntPtr.Zero) != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(newHandle);
- }
- }
-
- ~ObjcTrackingInformation()
- {
- if (_longWeakHandle != IntPtr.Zero && RuntimeImports.RhHandleGet(_longWeakHandle) != null)
- {
- GC.ReRegisterForFinalize(this);
- return;
- }
-
- if (_memory != IntPtr.Zero)
- {
- NativeMemory.Free((void*)_memory);
- _memory = IntPtr.Zero;
- }
- if (_longWeakHandle != IntPtr.Zero)
- {
- RuntimeImports.RhHandleFree(_longWeakHandle);
- _longWeakHandle = IntPtr.Zero;
- }
- }
- }
+ private static bool IsTrackedReferenceWithFinalizer(object obj)
+ => RuntimeHelpers.GetMethodTable(obj)->IsTrackedReferenceWithFinalizer;
  }
 }

src/coreclr/vm/CMakeLists.txt

@@ -59,6 +59,7 @@ set(VM_SOURCES_DAC_AND_WKS_COMMON
  clsload.cpp
  codeman.cpp
  codeversion.cpp
+ conditionalweaktable.cpp
  contractimpl.cpp
  corhost.cpp
  crst.cpp
@@ -277,7 +278,6 @@ list(APPEND VM_HEADERS_DAC_AND_WKS_COMMON
 
 set(VM_SOURCES_DAC
  ${VM_SOURCES_DAC_AND_WKS_COMMON}
- conditionalweaktable.cpp # The usage of conditionalweaktable is only in the DAC, but we put the headers in the VM to enable validation.
 )
 
 set(VM_HEADERS_DAC

src/coreclr/vm/binder.cpp

@@ -21,7 +21,7 @@
 #include "sigbuilder.h"
 #include "configuration.h"
 #include "conditionalweaktable.h"
-#include "interoplibinterface_comwrappers.h"
+#include "interoplibinterface.h"
 #include "assemblynative.hpp"
 
 //

src/coreclr/vm/conditionalweaktable.cpp

@@ -4,11 +4,20 @@
 
 #include "conditionalweaktable.h"
 #include "gchandleutilities.h"
+
+#ifdef DACCESS_COMPILE
 #include "../debug/daccess/gcinterface.dac.h"
+#endif // DACCESS_COMPILE
 
 bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF* value)
 {
- STANDARD_VM_CONTRACT;
+ CONTRACTL
+ {
+ NOTHROW;
+ GC_NOTRIGGER;
+ MODE_ANY;
+ }
+ CONTRACTL_END;
  SUPPORTS_DAC;
  _ASSERTE(key != nullptr && value != nullptr);
 
@@ -24,11 +33,19 @@ bool ConditionalWeakTableContainerObject::TryGetValue(OBJECTREF key, OBJECTREF*
  int bucket = hashCode & (_buckets->GetNumComponents() - 1);
  PTR_int32_t buckets = _buckets->GetDirectPointerToNonObjectElements();
  DPTR(Entry) entries = _entries->GetDirectPointerToNonObjectElements();
+
  for (int entriesIndex = buckets[bucket]; entriesIndex != -1; entriesIndex = entries[entriesIndex].Next)
  {
- if (entries[entriesIndex].HashCode == hashCode && ObjectFromHandle(entries[entriesIndex].depHnd) == key)
+ const Entry& entry = entries[entriesIndex];
+ if (entry.HashCode == hashCode && ObjectFromHandle(entry.depHnd) == key)
  {
- *value = HndGetHandleExtraInfo(entries[entriesIndex].depHnd);
+#ifdef DACCESS_COMPILE
+ // In the DACCESS_COMPILE, the handle helper is directly accessible.
+ *value = GetDependentHandleSecondary(entry.depHnd);
+#else
+ IGCHandleManager* mgr = GCHandleUtilities::GetGCHandleManager();
+ *value = ObjectToOBJECTREF(mgr->GetDependentHandleSecondary(entry.depHnd));
+#endif // !DACCESS_COMPILE
  return true;
  }
  }

src/coreclr/vm/conditionalweaktable.h

@@ -39,22 +39,20 @@ class ConditionalWeakTableContainerObject final : public Object
  ENTRYARRAYREF _entries;
 
 public:
-#ifdef DACCESS_COMPILE
  bool TryGetValue(OBJECTREF key, OBJECTREF* value);
-#endif
 };
 
 class ConditionalWeakTableObject final : public Object
 {
  friend class CoreLibBinder;
  OBJECTREF _lock;
- VolatilePtr<ConditionalWeakTableContainerObject, CONDITIONAL_WEAK_TABLE_CONTAINER_REF> _container;
+ VolatilePtr<ConditionalWeakTableContainerObject> _container;
 public:
-#ifdef DACCESS_COMPILE
- // Currently, we only use this for access from the DAC, so we don't need to worry about
- // locking or tracking the active enumerator count.
- // If we need to use this in a context where the runtime isn't suspended, we need to add
- // the locking and tracking support.
+ // This helper can be used when the runtime is suspended (for example, DAC access
+ // or Objective-C interop callbacks that run under GC suspension). During suspension
+ // the table shape is stable since no mutations can run, so lock-free lookup is safe.
+ // If we need to use this in a context where the runtime isn't suspended, we need to
+ // add locking and active enumerator tracking support.
  template<typename TKey, typename TValue>
  bool TryGetValue(TKey key, TValue* value)
  {
@@ -67,10 +65,8 @@ class ConditionalWeakTableObject final : public Object
  {
  *value = (TValue)valueObj;
  }
-
  return found;
  }
-#endif
 };
 
 #endif // CONDITIONAL_WEAK_TABLE_H

src/coreclr/vm/corelib.h

@@ -460,6 +460,9 @@ DEFINE_FIELD_U(_buckets, GCHandleSetObject, _buckets)
 #ifdef FEATURE_OBJCMARSHAL
 DEFINE_CLASS(OBJCMARSHAL, ObjectiveC, ObjectiveCMarshal)
 DEFINE_METHOD(OBJCMARSHAL, INVOKEUNHANDLEDEXCEPTIONPROPAGATION, InvokeUnhandledExceptionPropagation, SM_PtrException_IntPtr_PtrIntPtr_PtrException_RetVoidPtr)
+DEFINE_FIELD(OBJCMARSHAL, OBJECTS, s_objects)
+DEFINE_CLASS_U(ObjectiveC, ObjectiveCMarshal+ObjcTrackingInformation, ObjcTrackingInformationObject)
+DEFINE_FIELD_U(_memory, ObjcTrackingInformationObject, _memory)
 #endif // FEATURE_OBJCMARSHAL
 
 DEFINE_CLASS_U(Interop, TypeMapLazyDictionary+CallbackContext, CallbackContext)

src/coreclr/vm/datadescriptor/datadescriptor.inc

@@ -220,9 +220,6 @@ CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCW, cdac_data<InteropSyncBlock
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, RCW, cdac_data<InteropSyncBlockInfo>::RCW)
 CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, CCF, cdac_data<InteropSyncBlockInfo>::CCF)
 #endif // FEATURE_COMINTEROP
-#ifdef FEATURE_OBJCMARSHAL
-CDAC_TYPE_FIELD(InteropSyncBlockInfo, T_POINTER, TaggedMemory, cdac_data<InteropSyncBlockInfo>::TaggedMemory)
-#endif // FEATURE_OBJCMARSHAL
 CDAC_TYPE_END(InteropSyncBlockInfo)
 
 CDAC_TYPE_BEGIN(SyncBlock)