[turbofan] Properly implement %_ClassOf intrinsic.

src/compiler/js-intrinsic-lowering.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/js-intrinsic-lowering.h"
 
 #include <stack>
 
 #include "src/code-factory.h"
 #include "src/compiler/access-builder.h"
@@ skipping 64 matching lines @@
     case Runtime::kInlineCall:
       return ReduceCall(node);
     case Runtime::kInlineGetSuperConstructor:
       return ReduceGetSuperConstructor(node);
     case Runtime::kInlineJSCollectionGetTable:
       return ReduceJSCollectionGetTable(node);
     case Runtime::kInlineStringGetRawHashField:
       return ReduceStringGetRawHashField(node);
     case Runtime::kInlineTheHole:
       return ReduceTheHole(node);
+    case Runtime::kInlineClassOf:
+      return ReduceClassOf(node);
     default:
       break;
   }
   return NoChange();
 }
 
 
 Reduction JSIntrinsicLowering::ReduceCreateIterResultObject(Node* node) {
   Node* const value = NodeProperties::GetValueInput(node, 0);
   Node* const done = NodeProperties::GetValueInput(node, 1);
@@ skipping 237 matching lines @@
                 simplified()->LoadField(AccessBuilder::ForNameHashField()),
                 string, effect, control);
 }
 
 Reduction JSIntrinsicLowering::ReduceTheHole(Node* node) {
   Node* value = jsgraph()->TheHoleConstant();
   ReplaceWithValue(node, value);
   return Replace(value);
 }
 
+Reduction JSIntrinsicLowering::ReduceClassOf(Node* node) {
+  RelaxEffectsAndControls(node);
+  node->TrimInputCount(2);
+  NodeProperties::ChangeOp(node, javascript()->ClassOf());
+  return Changed(node);
+}
+
 Reduction JSIntrinsicLowering::Change(Node* node, const Operator* op, Node* a,
                                       Node* b) {
   RelaxControls(node);
   node->ReplaceInput(0, a);
   node->ReplaceInput(1, b);
   node->TrimInputCount(2);
   NodeProperties::ChangeOp(node, op);
   return Changed(node);
 }
 
@@ skipping 49 matching lines @@
   return jsgraph_->javascript();
 }
 
 SimplifiedOperatorBuilder* JSIntrinsicLowering::simplified() const {
   return jsgraph()->simplified();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8