diff --git a/tests/baselines/reference/classExpressionWithDecorator1.js b/tests/baselines/reference/classExpressionWithDecorator1.js
index fd15941996..3e25539890 100644
--- a/tests/baselines/reference/classExpressionWithDecorator1.js
+++ b/tests/baselines/reference/classExpressionWithDecorator1.js
@@ -2,25 +2,21 @@
 var v = @decorate class C { static p = 1 };
 
 //// [classExpressionWithDecorator1.js]
-var __decorate = this.__decorate || function (decorators, target, key, value) {
-    var kind = typeof (arguments.length == 2 ? value = target : value);
-    for (var i = decorators.length - 1; i >= 0; --i) {
-        var decorator = decorators[i];
-        switch (kind) {
-            case "function": value = decorator(value) || value; break;
-            case "number": decorator(target, key, value); break;
-            case "undefined": decorator(target, key); break;
-            case "object": value = decorator(target, key, value) || value; break;
-        }
+var __decorate = this.__decorate || (typeof Reflect === "object" && Reflect.decorate) || function (decorators, target, key, desc) {
+    switch (arguments.length) {
+        case 2: return decorators.reduceRight(function(o, d) { return (d && d(o)) || o; }, target);
+        case 3: return decorators.reduceRight(function(o, d) { return (d && d(target, key)), void 0; }, void 0);
+        case 4: return decorators.reduceRight(function(o, d) { return (d && d(target, key, o)) || o; }, desc);
     }
-    return value;
 };
 var v = ;
 var C = (function () {
     function C() {
     }
     C.p = 1;
-    C = __decorate([decorate], C);
+    C = __decorate([
+        decorate
+    ], C);
     return C;
 })();
 ;
diff --git a/tests/baselines/reference/decoratorOnClassAccessor3.js b/tests/baselines/reference/decoratorOnClassAccessor3.js
index a2a2221a11..23e689f311 100644
--- a/tests/baselines/reference/decoratorOnClassAccessor3.js
+++ b/tests/baselines/reference/decoratorOnClassAccessor3.js
@@ -6,18 +6,12 @@ class C {
 }
 
 //// [decoratorOnClassAccessor3.js]
-var __decorate = this.__decorate || function (decorators, target, key, value) {
-    var kind = typeof (arguments.length == 2 ? value = target : value);
-    for (var i = decorators.length - 1; i >= 0; --i) {
-        var decorator = decorators[i];
-        switch (kind) {
-            case "function": value = decorator(value) || value; break;
-            case "number": decorator(target, key, value); break;
-            case "undefined": decorator(target, key); break;
-            case "object": value = decorator(target, key, value) || value; break;
-        }
+var __decorate = this.__decorate || (typeof Reflect === "object" && Reflect.decorate) || function (decorators, target, key, desc) {
+    switch (arguments.length) {
+        case 2: return decorators.reduceRight(function(o, d) { return (d && d(o)) || o; }, target);
+        case 3: return decorators.reduceRight(function(o, d) { return (d && d(target, key)), void 0; }, void 0);
+        case 4: return decorators.reduceRight(function(o, d) { return (d && d(target, key, o)) || o; }, desc);
     }
-    return value;
 };
 var C = (function () {
     function C() {
@@ -27,6 +21,9 @@ var C = (function () {
         enumerable: true,
         configurable: true
     });
-    Object.defineProperty(C.prototype, "accessor", __decorate([dec], C.prototype, "accessor", Object.getOwnPropertyDescriptor(C.prototype, "accessor")));
+    Object.defineProperty(C.prototype, "accessor",
+        __decorate([
+            dec
+        ], C.prototype, "accessor", Object.getOwnPropertyDescriptor(C.prototype, "accessor")));
     return C;
 })();
diff --git a/tests/baselines/reference/decoratorOnClassAccessor6.js b/tests/baselines/reference/decoratorOnClassAccessor6.js
index ce9776bfc6..465e13ebb1 100644
--- a/tests/baselines/reference/decoratorOnClassAccessor6.js
+++ b/tests/baselines/reference/decoratorOnClassAccessor6.js
@@ -6,18 +6,12 @@ class C {
 }
 
 //// [decoratorOnClassAccessor6.js]
-var __decorate = this.__decorate || function (decorators, target, key, value) {
-    var kind = typeof (arguments.length == 2 ? value = target : value);
-    for (var i = decorators.length - 1; i >= 0; --i) {
-        var decorator = decorators[i];
-        switch (kind) {
-            case "function": value = decorator(value) || value; break;
-            case "number": decorator(target, key, value); break;
-            case "undefined": decorator(target, key); break;
-            case "object": value = decorator(target, key, value) || value; break;
-        }
+var __decorate = this.__decorate || (typeof Reflect === "object" && Reflect.decorate) || function (decorators, target, key, desc) {
+    switch (arguments.length) {
+        case 2: return decorators.reduceRight(function(o, d) { return (d && d(o)) || o; }, target);
+        case 3: return decorators.reduceRight(function(o, d) { return (d && d(target, key)), void 0; }, void 0);
+        case 4: return decorators.reduceRight(function(o, d) { return (d && d(target, key, o)) || o; }, desc);
     }
-    return value;
 };
 var C = (function () {
     function C() {
@@ -27,6 +21,9 @@ var C = (function () {
         enumerable: true,
         configurable: true
     });
-    Object.defineProperty(C.prototype, "accessor", __decorate([dec], C.prototype, "accessor", Object.getOwnPropertyDescriptor(C.prototype, "accessor")));
+    Object.defineProperty(C.prototype, "accessor",
+        __decorate([
+            dec
+        ], C.prototype, "accessor", Object.getOwnPropertyDescriptor(C.prototype, "accessor")));
     return C;
 })();
diff --git a/tests/baselines/reference/decoratorOnClassMethod3.js b/tests/baselines/reference/decoratorOnClassMethod3.js
index 7e13f91d86..f93b7d7a6b 100644
--- a/tests/baselines/reference/decoratorOnClassMethod3.js
+++ b/tests/baselines/reference/decoratorOnClassMethod3.js
@@ -6,23 +6,20 @@ class C {
 }
 
 //// [decoratorOnClassMethod3.js]
-var __decorate = this.__decorate || function (decorators, target, key, value) {
-    var kind = typeof (arguments.length == 2 ? value = target : value);
-    for (var i = decorators.length - 1; i >= 0; --i) {
-        var decorator = decorators[i];
-        switch (kind) {
-            case "function": value = decorator(value) || value; break;
-            case "number": decorator(target, key, value); break;
-            case "undefined": decorator(target, key); break;
-            case "object": value = decorator(target, key, value) || value; break;
-        }
+var __decorate = this.__decorate || (typeof Reflect === "object" && Reflect.decorate) || function (decorators, target, key, desc) {
+    switch (arguments.length) {
+        case 2: return decorators.reduceRight(function(o, d) { return (d && d(o)) || o; }, target);
+        case 3: return decorators.reduceRight(function(o, d) { return (d && d(target, key)), void 0; }, void 0);
+        case 4: return decorators.reduceRight(function(o, d) { return (d && d(target, key, o)) || o; }, desc);
     }
-    return value;
 };
 var C = (function () {
     function C() {
     }
     C.prototype.method = function () { };
-    Object.defineProperty(C.prototype, "method", __decorate([dec], C.prototype, "method", Object.getOwnPropertyDescriptor(C.prototype, "method")));
+    Object.defineProperty(C.prototype, "method",
+        __decorate([
+            dec
+        ], C.prototype, "method", Object.getOwnPropertyDescriptor(C.prototype, "method")));
     return C;
 })();
diff --git a/tests/baselines/reference/decoratorOnClassProperty3.js b/tests/baselines/reference/decoratorOnClassProperty3.js
index f8a2cce27d..05476c66e7 100644
--- a/tests/baselines/reference/decoratorOnClassProperty3.js
+++ b/tests/baselines/reference/decoratorOnClassProperty3.js
@@ -6,22 +6,18 @@ class C {
 }
 
 //// [decoratorOnClassProperty3.js]
-var __decorate = this.__decorate || function (decorators, target, key, value) {
-    var kind = typeof (arguments.length == 2 ? value = target : value);
-    for (var i = decorators.length - 1; i >= 0; --i) {
-        var decorator = decorators[i];
-        switch (kind) {
-            case "function": value = decorator(value) || value; break;
-            case "number": decorator(target, key, value); break;
-            case "undefined": decorator(target, key); break;
-            case "object": value = decorator(target, key, value) || value; break;
-        }
+var __decorate = this.__decorate || (typeof Reflect === "object" && Reflect.decorate) || function (decorators, target, key, desc) {
+    switch (arguments.length) {
+        case 2: return decorators.reduceRight(function(o, d) { return (d && d(o)) || o; }, target);
+        case 3: return decorators.reduceRight(function(o, d) { return (d && d(target, key)), void 0; }, void 0);
+        case 4: return decorators.reduceRight(function(o, d) { return (d && d(target, key, o)) || o; }, desc);
     }
-    return value;
 };
 var C = (function () {
     function C() {
     }
-    __decorate([dec], C.prototype, "prop");
+    __decorate([
+        dec
+    ], C.prototype, "prop");
     return C;
 })();