Extend metadata schema to support function pointers (#1928)

Also:
* update `MetadataTransform` to emit the new metadata
* a simple unit test

2 files changed, 87 insertions, 0 deletions

diff --git a/src/ILCompiler.MetadataWriter/src/Internal/Metadata/NativeFormat/Writer/MdBinaryWriterGen.cs b/src/ILCompiler.MetadataWriter/src/Internal/Metadata/NativeFormat/Writer/MdBinaryWriterGen.cs
index 2767c25ae..e49f28b49 100644
--- a/src/ILCompiler.MetadataWriter/src/Internal/Metadata/NativeFormat/Writer/MdBinaryWriterGen.cs
+++ b/src/ILCompiler.MetadataWriter/src/Internal/Metadata/NativeFormat/Writer/MdBinaryWriterGen.cs
@@ -1086,6 +1086,28 @@ namespace Internal.Metadata.NativeFormat.Writer
             }
         } // Write
 
+        public static void Write(this NativeWriter writer, FunctionPointerSignature record)
+        {
+            if (record != null)
+                writer.WriteUnsigned((uint)record.Handle.Offset);
+            else
+                writer.WriteUnsigned(0);
+        } // Write
+
+        public static void Write(this NativeWriter writer, List<FunctionPointerSignature> values)
+        {
+            if (values == null)
+            {
+                writer.WriteUnsigned(0);
+                return;
+            }
+            writer.WriteUnsigned((uint)values.Count);
+            foreach (FunctionPointerSignature value in values)
+            {
+                writer.Write(value);
+            }
+        } // Write
+
         public static void Write(this NativeWriter writer, GenericParameter record)
         {
             if (record != null)
diff --git a/src/ILCompiler.MetadataWriter/src/Internal/Metadata/NativeFormat/Writer/NativeFormatWriterGen.cs b/src/ILCompiler.MetadataWriter/src/Internal/Metadata/NativeFormat/Writer/NativeFormatWriterGen.cs
index 1afe7ecdc..79e969c0a 100644
--- a/src/ILCompiler.MetadataWriter/src/Internal/Metadata/NativeFormat/Writer/NativeFormatWriterGen.cs
+++ b/src/ILCompiler.MetadataWriter/src/Internal/Metadata/NativeFormat/Writer/NativeFormatWriterGen.cs
@@ -2612,6 +2612,70 @@ namespace Internal.Metadata.NativeFormat.Writer
         public MetadataRecord Value;
     } // FixedArgument
 
+    public partial class FunctionPointerSignature : MetadataRecord
+    {
+        public override HandleType HandleType
+        {
+            get
+            {
+                return HandleType.FunctionPointerSignature;
+            }
+        } // HandleType
+
+        internal override void Visit(IRecordVisitor visitor)
+        {
+            Signature = visitor.Visit(this, Signature);
+        } // Visit
+
+        public override sealed bool Equals(Object obj)
+        {
+            if (Object.ReferenceEquals(this, obj)) return true;
+            var other = obj as FunctionPointerSignature;
+            if (other == null) return false;
+            if (!Object.Equals(Signature, other.Signature)) return false;
+            return true;
+        } // Equals
+
+        public override sealed int GetHashCode()
+        {
+            if (_hash != 0)
+                return _hash;
+            EnterGetHashCode();
+            int hash = 1733451879;
+            hash = ((hash << 13) - (hash >> 19)) ^ (Signature == null ? 0 : Signature.GetHashCode());
+            LeaveGetHashCode();
+            _hash = hash;
+            return _hash;
+        } // GetHashCode
+
+        internal override void Save(NativeWriter writer)
+        {
+            writer.Write(Signature);
+        } // Save
+
+        internal static FunctionPointerSignatureHandle AsHandle(FunctionPointerSignature record)
+        {
+            if (record == null)
+            {
+                return new FunctionPointerSignatureHandle(0);
+            }
+            else
+            {
+                return record.Handle;
+            }
+        } // AsHandle
+
+        internal new FunctionPointerSignatureHandle Handle
+        {
+            get
+            {
+                return new FunctionPointerSignatureHandle(HandleOffset);
+            }
+        } // Handle
+
+        public MethodSignature Signature;
+    } // FunctionPointerSignature
+
     public partial class GenericParameter : MetadataRecord
     {
         public override HandleType HandleType
@@ -4813,6 +4877,7 @@ namespace Internal.Metadata.NativeFormat.Writer
                 Signature.HandleType == HandleType.SZArraySignature ||
                 Signature.HandleType == HandleType.ArraySignature ||
                 Signature.HandleType == HandleType.PointerSignature ||
+                Signature.HandleType == HandleType.FunctionPointerSignature ||
                 Signature.HandleType == HandleType.ByReferenceSignature ||
                 Signature.HandleType == HandleType.TypeVariableSignature ||
                 Signature.HandleType == HandleType.MethodTypeVariableSignature);