Adding GetClrNotification cDAC API

src/coreclr/debug/runtimeinfo/datadescriptor.h

@@ -959,6 +959,8 @@ CDAC_GLOBAL(MethodDescAlignment, uint64, MethodDesc::ALIGNMENT)
 CDAC_GLOBAL(ObjectHeaderSize, uint64, OBJHEADER_SIZE)
 CDAC_GLOBAL(SyncBlockValueToObjectOffset, uint16, OBJHEADER_SIZE - cdac_data<ObjHeader>::SyncBlockValue)
 CDAC_GLOBAL(StubCodeBlockLast, uint8, STUB_CODE_BLOCK_LAST)
+CDAC_GLOBAL(MaxClrNotificationArgs, uint32, MAX_CLR_NOTIFICATION_ARGS)
+CDAC_GLOBAL_POINTER(ClrNotificationArguments, &::g_clrNotificationArguments)
 CDAC_GLOBAL_POINTER(ArrayBoundsZero, cdac_data<ArrayBase>::ArrayBoundsZero)
 CDAC_GLOBAL_POINTER(ExceptionMethodTable, &::g_pExceptionClass)
 CDAC_GLOBAL_POINTER(FreeObjectMethodTable, &::g_pFreeObjectMethodTable)

src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Constants.cs

@@ -53,6 +53,8 @@ public static class Globals
 
         public const string ExecutionManagerCodeRangeMapAddress = nameof(ExecutionManagerCodeRangeMapAddress);
         public const string StubCodeBlockLast = nameof(StubCodeBlockLast);
+        public const string MaxClrNotificationArgs = nameof(MaxClrNotificationArgs);
+        public const string ClrNotificationArguments = nameof(ClrNotificationArguments);
         public const string PlatformMetadata = nameof(PlatformMetadata);
         public const string ProfilerControlBlock = nameof(ProfilerControlBlock);
 

src/native/managed/cdac/mscordaccore_universal/Legacy/SOSDacImpl.cs

@@ -1851,7 +1851,48 @@ int ISOSDacInterface3.GetGCGlobalMechanisms(nuint* globalMechanisms)
 
     #region ISOSDacInterface4
     int ISOSDacInterface4.GetClrNotification(ClrDataAddress[] arguments, int count, int* pNeeded)
-        => _legacyImpl4 is not null ? _legacyImpl4.GetClrNotification(arguments, count, pNeeded) : HResults.E_NOTIMPL;
+    {
+        int hr = HResults.S_OK;
+        uint MaxClrNotificationArgs = _target.ReadGlobal<uint>(Constants.Globals.MaxClrNotificationArgs);
+        try
+        {
+            *pNeeded = (int)MaxClrNotificationArgs;
+            TargetPointer basePtr = _target.ReadGlobalPointer(Constants.Globals.ClrNotificationArguments);
+            if (_target.ReadNUInt(basePtr).Value == 0)
+            {
+                hr = HResults.E_FAIL;
+            }
+            else
+            {
+                for (int i = 0; i < count && i < MaxClrNotificationArgs; i++)
+                {
+                    arguments[i] = _target.ReadNUInt(basePtr.Value + (ulong)(i * _target.PointerSize)).Value;
+                }
+            }
+        }
+        catch (System.Exception ex)
+        {
+            hr = ex.HResult;
+        }
+#if DEBUG
+        if (_legacyImpl4 is not null)
+        {
+            ClrDataAddress[] argumentsLocal = new ClrDataAddress[count];
+            int neededLocal;
+            int hrLocal = _legacyImpl4.GetClrNotification(argumentsLocal, count, &neededLocal);
+            Debug.Assert(hrLocal == hr, $"cDAC: {hr:x}, DAC: {hrLocal:x}");
+            if (hr == HResults.S_OK)
+            {
+                Debug.Assert(*pNeeded == neededLocal);
+                for (int i = 0; i < count && i < MaxClrNotificationArgs; i++)
+                {
+                    Debug.Assert(arguments[i] == argumentsLocal[i]);
+                }
+            }
+        }
+#endif
+        return hr;
+    }
     #endregion ISOSDacInterface4
 
     #region ISOSDacInterface5