[turbofan] Optimize strict equality of unique values.

src/compiler/js-typed-lowering.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/code-factory.h"
 #include "src/compiler/access-builder.h"
 #include "src/compiler/js-graph.h"
 #include "src/compiler/js-typed-lowering.h"
 #include "src/compiler/linkage.h"
 #include "src/compiler/node-matchers.h"
@@ skipping 548 matching lines @@
                                   invert);
   }
   if (r.OneInputIs(Type::Object())) {
     return r.ChangeToPureOperator(simplified()->ReferenceEqual(Type::Object()),
                                   invert);
   }
   if (r.OneInputIs(Type::Receiver())) {
     return r.ChangeToPureOperator(
         simplified()->ReferenceEqual(Type::Receiver()), invert);
   }
+  if (r.BothInputsAre(Type::Unique())) {
+    return r.ChangeToPureOperator(simplified()->ReferenceEqual(Type::Unique()),
+                                  invert);
+  }
   if (r.BothInputsAre(Type::String())) {
     return r.ChangeToPureOperator(simplified()->StringEqual(), invert);
   }
   if (r.BothInputsAre(Type::Number())) {
     return r.ChangeToPureOperator(simplified()->NumberEqual(), invert);
   }
   // TODO(turbofan): js-typed-lowering of StrictEqual(mixed types)
   return NoChange();
 }
 
@@ skipping 624 matching lines @@
 }
 
 
 MachineOperatorBuilder* JSTypedLowering::machine() const {
   return jsgraph()->machine();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8