Initial support for preinitialized array in CoreRT (#3558)

* Add PreInitFieldInfo that extracts preinitialized data information from fields that have [PreInitialized] and [InitDataBlob] pointing to RVA field
* Added FrozenArrayNode for frozen arrays with data extracted from preinit RVA data field
* Added GCStaticsPreInitDataNode (CoreRT only) to hold GC pointers for GC static fields. Pre-init data fields points to frozen data, while other data initialized to null. 
* Changed GCStaticsNode to emit a pointer reloc to GCStaticspreInitDataNode and mask 0x2 for the GC static EEType. 
* Changed InitializedStatics in StartupCodeHelper to check for 0x2 and memcpy the GC field data as needed
* Fixed a bug in bad GCStaticsEETypeNode size calculation - it's off-by-1 as static GC static field layout in CoreRT includes EEType already.

1 files changed, 10 insertions, 0 deletions

diff --git a/src/System.Private.CoreLib/src/System/Object.cs b/src/System.Private.CoreLib/src/System/Object.cs
index 22dc37a1b..7207d24f6 100644
--- a/src/System.Private.CoreLib/src/System/Object.cs
+++ b/src/System.Private.CoreLib/src/System/Object.cs
@@ -22,6 +22,7 @@ using Internal.Reflection.Core.NonPortable;
 
 #if INPLACE_RUNTIME
 using EEType = Internal.Runtime.EEType;
+using ObjHeader = Internal.Runtime.ObjHeader;
 #endif
 
 namespace System
@@ -152,6 +153,15 @@ namespace System
         {
             return ref Unsafe.As<RawData>(this).Data;
         }
+
+        /// <summary>
+        /// Return size of all data (excluding ObjHeader and EEType*).
+        /// Note that for strings/arrays this would include the Length as well. 
+        /// </summary>
+        internal uint GetRawDataSize()
+        {
+            return EETypePtr.BaseSize - (uint)sizeof(ObjHeader) - (uint)sizeof(EEType*);
+        }
     }
 }