Reserve some RDAT/DXIL enum values used by the mesh node preview (microsoft#6818)

Let's ensure we don't accidentally stomp on these. If we do choose to
break them, it should be intentional, not accidental.

Author: jenatali

include/dxc/DXIL/DxilConstants.h

@@ -1604,6 +1604,7 @@ enum class NodeLaunchType {
   Broadcasting,
   Coalescing,
   Thread,
+  Reserved_Mesh,
 
   LastEntry
 };

include/dxc/DxilContainer/DxilRuntimeReflection.h

@@ -68,6 +68,8 @@ enum class RuntimeDataPartType : uint32_t {
   NodeShaderInfoTable = 11,
   Last_1_8 = NodeShaderInfoTable,
 
+  Reserved_MeshNodesPreviewInfoTable = 12,
+
   // Insert experimental here.
   SignatureElementTable,
   VSInfoTable,
@@ -113,6 +115,8 @@ enum class RecordTableIndex : unsigned {
   IONodeTable,
   NodeShaderInfoTable,
 
+  Reserved_MeshNodesPreviewInfoTable,
+
   DxilPdbInfoTable,
   DxilPdbInfoSourceTable,
   DxilPdbInfoLibraryTable,

include/dxc/DxilContainer/RDAT_LibraryTypes.inl

@@ -265,6 +265,8 @@ RDAT_ENUM_START(NodeFuncAttribKind, uint32_t)
   RDAT_ENUM_VALUE(MaxRecursionDepth, 5)
   RDAT_ENUM_VALUE(LocalRootArgumentsTableIndex, 6)
   RDAT_ENUM_VALUE(MaxDispatchGrid, 7)
+  RDAT_ENUM_VALUE(Reserved_MeshNodePreview1, 8)
+  RDAT_ENUM_VALUE(Reserved_MeshNodePreview2, 9)
   RDAT_ENUM_VALUE_NODEF(LastValue)
 RDAT_ENUM_END()
 
@@ -307,9 +309,10 @@ RDAT_DXIL_ENUM_START(hlsl::DXIL::NodeLaunchType, uint32_t)
   RDAT_ENUM_VALUE_NODEF(Broadcasting)
   RDAT_ENUM_VALUE_NODEF(Coalescing)
   RDAT_ENUM_VALUE_NODEF(Thread)
+  RDAT_ENUM_VALUE_NODEF(Reserved_Mesh)
   RDAT_ENUM_VALUE_NODEF(LastEntry)
 #if DEF_RDAT_ENUMS == DEF_RDAT_DUMP_IMPL
-  static_assert((unsigned)hlsl::DXIL::NodeLaunchType::LastEntry == 4,
+  static_assert((unsigned)hlsl::DXIL::NodeLaunchType::LastEntry == 5,
                 "otherwise, RDAT_DXIL_ENUM definition needs updating");
 #endif
 RDAT_ENUM_END()