1 files changed, 98 insertions, 0 deletions
diff --git a/src/vm/generics.inl b/src/vm/generics.inl
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+++ b/src/vm/generics.inl
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+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+//
+// File: generics.inl
+//
+
+//
+// Helper functions for generics implementation
+//
+
+//
+// ============================================================================
+
+#ifndef GENERICS_INL
+#define GENERICS_INL
+
+#ifdef FEATURE_COMINTEROP
+#include "winrttypenameconverter.h"
+#endif
+
+// Generics helper functions
+namespace Generics
+{
+#ifndef DACCESS_COMPILE
+    inline void DetermineCCWTemplateAndGUIDPresenceOnNonCanonicalMethodTable(
+        // Input
+        MethodTable *pOldMT, BOOL fNewMTContainsGenericVariables,
+        // Output
+        BOOL *pfHasGuidInfo, BOOL *pfHasCCWTemplate)
+    {
+        STANDARD_VM_CONTRACT;
+
+#ifdef FEATURE_COMINTEROP 
+        WORD wNumInterfaces = static_cast<WORD>(pOldMT->GetNumInterfaces());
+
+        InterfaceInfo_t * pOldIMap = (InterfaceInfo_t *)pOldMT->GetInterfaceMap();
+
+        BOOL fHasGuidInfo = FALSE;
+
+        // Generic WinRT delegates expose a class interface and need the CCW template
+        BOOL fHasCCWTemplate = FALSE;
+    
+        if (!fNewMTContainsGenericVariables)
+        {
+            if (pOldMT->IsInterface())
+            {
+                fHasGuidInfo = (pOldMT->IsProjectedFromWinRT() || WinRTTypeNameConverter::IsRedirectedType(pOldMT, WinMDAdapter::WinMDTypeKind_PInterface));
+            }
+            else if (pOldMT->IsDelegate())
+            {
+                fHasGuidInfo = (pOldMT->IsProjectedFromWinRT() || WinRTTypeNameConverter::IsRedirectedType(pOldMT, WinMDAdapter::WinMDTypeKind_PDelegate));
+                
+                // Generic WinRT delegates expose a class interface and need a CCW template
+                fHasCCWTemplate = fHasGuidInfo;
+            }
+            
+            if (!fHasCCWTemplate)
+            {
+                if (pOldMT->IsInterface())
+                {
+                    // Interfaces need the CCW template if they are redirected and need variance
+                    if (pOldMT->HasVariance() &&
+                        (pOldMT->IsProjectedFromWinRT() || WinRTTypeNameConverter::IsRedirectedType(pOldMT, WinMDAdapter::WinMDTypeKind_PInterface)))
+                        {
+                            fHasCCWTemplate = TRUE;
+                        }
+                }
+                else
+                {
+                    // Other types may need the CCW template if they implement generic interfaces
+                    for (WORD iItf = 0; iItf < wNumInterfaces; iItf++)
+                    {
+                        // If the class implements a generic WinRT interface, it needs its own (per-instantiation)
+                        // CCW template as the one on EEClass would be shared and hence useless.
+                        OVERRIDE_TYPE_LOAD_LEVEL_LIMIT(CLASS_LOAD_APPROXPARENTS);
+                        MethodTable *pItfMT = pOldIMap[iItf].GetApproxMethodTable(pOldMT->GetLoaderModule());
+                        if (pItfMT->HasInstantiation() && 
+                            (pItfMT->IsProjectedFromWinRT() || WinRTTypeNameConverter::IsRedirectedType(pItfMT, WinMDAdapter::WinMDTypeKind_PInterface)))
+                        {
+                            fHasCCWTemplate = TRUE;
+                            break;
+                        }
+                    }
+                }
+            }
+        }
+#else // FEATURE_COMINTEROP
+        BOOL fHasGuidInfo = FALSE;
+        BOOL fHasCCWTemplate = FALSE;
+#endif // FEATURE_COMINTEROP
+        *pfHasGuidInfo = fHasGuidInfo;
+        *pfHasCCWTemplate = fHasCCWTemplate;
+    }
+#endif // DACCESS_COMPILE
+}
+
+#endif // GENERICS_INL