Fix array performance regression (#1148)

Jint/Native/Array/ArrayOperations.cs

@@ -72,7 +72,7 @@ namespace Jint.Native.Array
 
         public abstract void CreateDataPropertyOrThrow(ulong index, JsValue value);
 
-        public abstract void Set(ulong index, JsValue value, bool throwOnError);
+        public abstract void Set(ulong index, JsValue value, bool updateLength = false, bool throwOnError = true);
 
         public abstract void DeletePropertyOrThrow(ulong index);
 
@@ -226,7 +226,7 @@ namespace Jint.Native.Array
             public override void CreateDataPropertyOrThrow(ulong index, JsValue value)
                 => _target.CreateDataPropertyOrThrow(JsString.Create(index), value);
 
-            public override void Set(ulong index, JsValue value, bool throwOnError)
+            public override void Set(ulong index, JsValue value, bool updateLength = false, bool throwOnError = true)
                 => _target.Set(JsString.Create(index), value, throwOnError);
 
             public override void DeletePropertyOrThrow(ulong index)
@@ -297,8 +297,8 @@ namespace Jint.Native.Array
             public override void CreateDataPropertyOrThrow(ulong index, JsValue value)
                 => _target.SetIndexValue((uint) index, value, updateLength: false);
 
-            public override void Set(ulong index, JsValue value, bool throwOnError)
-                => _target.Set((uint) index, value, throwOnError);
+            public override void Set(ulong index, JsValue value, bool updateLength = false, bool throwOnError = true)
+                => _target.SetIndexValue((uint) index, value, updateLength);
         }
 
         private sealed class TypedArrayInstanceOperations : ArrayOperations
@@ -357,7 +357,7 @@ namespace Jint.Native.Array
             public override void CreateDataPropertyOrThrow(ulong index, JsValue value)
                 => _target.CreateDataPropertyOrThrow(index, value);
 
-            public override void Set(ulong index, JsValue value, bool throwOnError)
+            public override void Set(ulong index, JsValue value, bool updateLength = false, bool throwOnError = true)
                 => _target[(int) index] = value;
 
             public override void DeletePropertyOrThrow(ulong index)
@@ -381,4 +381,4 @@ namespace Jint.Native.Array
 
         public override ObjectInstance Target => _target;
     }
-}
+}

Jint/Native/Array/ArrayPrototype.cs

@@ -260,7 +260,7 @@ namespace Jint.Native.Array
                 if (fromPresent)
                 {
                     var fromValue = operations.Get((ulong) from);
-                    operations.Set((ulong) to, fromValue, throwOnError: true);
+                    operations.Set((ulong) to, fromValue, updateLength: true, throwOnError: true);
                 }
                 else
                 {
@@ -994,7 +994,8 @@ namespace Jint.Native.Array
         /// </summary>
         private JsValue Sort(JsValue thisObj, JsValue[] arguments)
         {
-            var obj = ArrayOperations.For(TypeConverter.ToObject(_realm, thisObj));
+            var objectInstance = TypeConverter.ToObject(_realm, thisObj);
+            var obj = ArrayOperations.For(objectInstance);
 
             var compareArg = arguments.At(0);
             ICallable compareFn = null;
@@ -1034,12 +1035,11 @@ namespace Jint.Native.Array
                 uint j;
                 for (j = 0; j < itemCount; ++j)
                 {
-                    if (!ReferenceEquals(array[j], null))
-                    {
-                        obj.Set(j, array[j], throwOnError: true);
-                    }
+                    objectInstance.Set(j, array[j], throwOnError: true);
+                    // TODO if we could keep track of data descriptors and whether prototype chain is unchanged
+                    // we could do faster direct write
+                    // obj.Set(j, array[j], updateLength: true, throwOnError: true);
                 }
-
                 for (; j < len; ++j)
                 {
                     obj.DeletePropertyOrThrow(j);

Jint/Native/Object/ObjectInstance.cs

@@ -1,7 +1,6 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
-using System.Dynamic;
 using System.Linq;
 using System.Runtime.CompilerServices;
 using Jint.Collections;