Revert "Try fixing some size regressions"

This reverts commit e383966.

Author: MichalStrehovsky

src/coreclr/nativeaot/System.Private.CoreLib/src/System/ValueType.cs

@@ -127,11 +127,11 @@ private unsafe void RegularGetValueTypeHashCode(ref HashCode hashCode, ref byte
 
                 if (fieldType->ElementType == EETypeElementType.Single)
                 {
-                    hashCode.Add(Unsafe.As<byte, float>(ref fieldData).GetHashCode());
+                    hashCode.Add(Unsafe.As<byte, float>(ref fieldData));
                 }
                 else if (fieldType->ElementType == EETypeElementType.Double)
                 {
-                    hashCode.Add(Unsafe.As<byte, double>(ref fieldData).GetHashCode());
+                    hashCode.Add(Unsafe.As<byte, double>(ref fieldData));
                 }
                 else if (fieldType->IsPrimitive)
                 {

src/coreclr/tools/aot/ILCompiler.Compiler/IL/ILImporter.Scanner.cs

@@ -959,23 +959,6 @@ private void ImportLdToken(int token)
                     }
                 }
 
-                // We might also be able to optimize this if this is typeof(Foo).IsValueType
-                if (helperId != ReadyToRunHelperId.NecessaryTypeHandle)
-                {
-                    reader = new ILReader(_ilBytes, _currentOffset);
-                    if (reader.HasNext
-                        && reader.ReadILOpcode() == ILOpcode.call
-                        && IsTypeGetTypeFromHandle((MethodDesc)_methodIL.GetObject(reader.ReadILToken())))
-                    {
-                        if (reader.HasNext
-                            && reader.ReadILOpcode() is ILOpcode.callvirt or ILOpcode.call
-                            && _methodIL.GetObject(reader.ReadILToken()) is MethodDesc { Name: "get_IsValueType" or "get_IsEnum"})
-                        {
-                            helperId = ReadyToRunHelperId.NecessaryTypeHandle;
-                        }
-                    }
-                }
-
                 _factory.MetadataManager.GetDependenciesDueToAccess(ref _dependencies, _factory, _methodIL, (TypeDesc)_canonMethodIL.GetObject(token));
 
                 _dependencies.Add(GetHelperEntrypoint(ReadyToRunHelper.GetRuntimeTypeHandle), "ldtoken");
@@ -1160,8 +1143,10 @@ private void ImportBox(int token)
         {
             var type = (TypeDesc)_methodIL.GetObject(token);
 
-            // Some box operations will trivially be eliminated during import
-            if (!type.IsRuntimeDeterminedType)
+            // There are some sequences of box with ByRefLike types that are allowed
+            // per the extension to the ECMA-335 specification.
+            // Everything else is invalid.
+            if (!type.IsRuntimeDeterminedType && type.IsByRefLike)
             {
                 ILReader reader = new ILReader(_ilBytes, _currentOffset);
                 ILOpcode nextOpcode = reader.ReadILOpcode();
@@ -1195,9 +1180,7 @@ private void ImportBox(int token)
                     }
                 }
 
-                // If this is a byref-like type, only the above operations are permitted.
-                if (type.IsByRefLike)
-                    ThrowHelper.ThrowInvalidProgramException();
+                ThrowHelper.ThrowInvalidProgramException();
             }
 
             AddBoxingDependencies(type, "Box");
@@ -1370,7 +1353,6 @@ private void ImportConvert(WellKnownType wellKnownType, bool checkOverflow, bool
         {
             if (checkOverflow)
             {
-                //
                 _dependencies.Add(GetHelperEntrypoint(ReadyToRunHelper.Dbl2IntOvf), "_dbl2intovf");
                 _dependencies.Add(GetHelperEntrypoint(ReadyToRunHelper.Dbl2UIntOvf), "_dbl2uintovf");
                 _dependencies.Add(GetHelperEntrypoint(ReadyToRunHelper.Dbl2LngOvf), "_dbl2lngovf");