[turbofan] Properly implement %_ClassOf intrinsic.

src/compiler/verifier.cc

 // Copyright 2014 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/verifier.h"
 
 #include <algorithm>
 #include <deque>
 #include <queue>
 #include <sstream>
@@ skipping 618 matching lines @@
       // Type is empty.
       CheckNotTyped(node);
       break;
     case IrOpcode::kJSDeleteProperty:
     case IrOpcode::kJSHasProperty:
     case IrOpcode::kJSInstanceOf:
     case IrOpcode::kJSOrdinaryHasInstance:
       // Type is Boolean.
       CheckTypeIs(node, Type::Boolean());
       break;
+    case IrOpcode::kJSClassOf:
+      // Type is InternaliedString \/ Null.
+      CheckTypeIs(node, Type::InternalizedStringOrNull());
+      break;
     case IrOpcode::kJSTypeOf:
-      // Type is String.
-      CheckTypeIs(node, Type::String());
+      // Type is InternalizedString.
+      CheckTypeIs(node, Type::InternalizedString());
       break;
     case IrOpcode::kJSGetSuperConstructor:
       // We don't check the input for Type::Function because
       // this_function can be context-allocated.
       // Any -> Callable.
       CheckValueInputIs(node, 0, Type::Any());
       CheckTypeIs(node, Type::Callable());
       break;
 
     case IrOpcode::kJSLoadContext:
@@ skipping 1031 matching lines @@
          replacement->op()->EffectOutputCount() > 0);
   DCHECK(!NodeProperties::IsFrameStateEdge(edge) ||
          replacement->opcode() == IrOpcode::kFrameState);
 }
 
 #endif  // DEBUG
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8