Fixes and tests

- Add quick fix to Stfld transformation
- Add test to ValueTypeTests to test for structs that contain struct
type fields

Source/Mosa.Compiler.Framework/Stages/CILTransformationStage.cs

@@ -1549,7 +1549,7 @@ private void Stfld(Context context)
 			}
 			else
 			{
-				var storeInstruction = GetStoreInstruction(context.Operand1.Type);
+				var storeInstruction = GetStoreInstruction(fieldType);
 				context.SetInstruction(storeInstruction, size, null, objectOperand, offsetOperand, valueOperand);
 				context.MosaType = fieldType;
 			}

Source/Mosa.UnitTest.Collection/ValueTypeTests.cs

@@ -27,6 +27,11 @@ private class wrapper
 			public valuetype content;
 		}
 
+		private struct valuewrapper
+		{
+			public valuetype content;
+		}
+
 		public static bool TestValueTypeVariable()
 		{
 			valuetype p = new valuetype();
@@ -64,6 +69,21 @@ public static bool TestValueTypeInstanceField()
 			return obj.content.a == 1 && obj.content.b == 7 & obj.content.c == 21 && obj.content.d == 171;
 		}
 
+		public static bool TestNestedValueTypeField()
+		{
+			valuetype p = new valuetype();
+			p.a = 1;
+			p.b = 7;
+			p.c = 21;
+			p.d = 171;
+
+			valuewrapper val = new valuewrapper();
+			val.content = p;
+
+			valuetype r = val.content;
+			return r.a == 1 && r.b == 7 & r.c == 21 && r.d == 171;
+		}
+
 		private static bool ParameterOk(valuetype p)
 		{
 			return p.a == 1 && p.b == 7 & p.c == 21 && p.d == 171;