Initial population of CoreRT Runtime files.

1 files changed, 48 insertions, 0 deletions

diff --git a/src/Native/Runtime/CachedInterfaceDispatch.h b/src/Native/Runtime/CachedInterfaceDispatch.h
new file mode 100644
index 000000000..596c0d705
--- /dev/null
+++ b/src/Native/Runtime/CachedInterfaceDispatch.h
@@ -0,0 +1,48 @@
+//
+// Copyright (c) Microsoft Corporation.  All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+// ==--==
+//
+// Shared (non-architecture specific) portions of a mechanism to perform interface dispatch using an alternate
+// mechanism to VSD that does not require runtime generation of code.
+//
+// ============================================================================
+
+#ifdef FEATURE_CACHED_INTERFACE_DISPATCH
+
+bool InitializeInterfaceDispatch();
+void ReclaimUnusedInterfaceDispatchCaches();
+
+// Interface dispatch caches contain an array of these entries. An instance of a cache is paired with a stub
+// that implicitly knows how many entries are contained. These entries must be aligned to twice the alignment
+// of a pointer due to the synchonization mechanism used to update them at runtime.
+struct InterfaceDispatchCacheEntry
+{
+    EEType *    m_pInstanceType;    // Potential type of the object instance being dispatched on
+    void *      m_pTargetCode;      // Method to dispatch to if the actual instance type matches the above
+};
+
+// The interface dispatch cache itself. As well as the entries we include the cache size (since logic such as
+// cache miss processing needs to determine this value in a synchronized manner, so it can't be contained in
+// the owning interface dispatch indirection cell) and a list entry used to link the caches in one of a couple
+// of lists related to cache reclamation.
+#pragma warning(push)
+#pragma warning(disable:4200) // nonstandard extension used: zero-sized array in struct/union
+struct InterfaceDispatchCell;
+struct InterfaceDispatchCache
+{
+    InterfaceDispatchCacheHeader m_cacheHeader;
+    union
+    {
+        InterfaceDispatchCache *    m_pNextFree;    // next in free list
+#ifndef _AMD64_
+        InterfaceDispatchCell  *    m_pCell;        // pointer back to interface dispatch cell - not used for AMD64
+#endif
+    };
+    UInt32                      m_cEntries;
+    InterfaceDispatchCacheEntry m_rgEntries[];
+};
+#pragma warning(pop)
+
+#endif // FEATURE_CACHED_INTERFACE_DISPATCH