[turbofan] Introduce a dedicated Array type.

test/cctest/test-types.cc

 // Copyright 2013 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 <vector>
 
 #include "src/compiler/types.h"
 #include "src/crankshaft/hydrogen-types.h"
 #include "src/factory.h"
 #include "src/heap/heap.h"
@@ skipping 613 matching lines @@
     CheckSub(T.InternalizedString, T.UniqueName);
     CheckSub(T.InternalizedString, T.Name);
     CheckSub(T.Symbol, T.UniqueName);
     CheckSub(T.Symbol, T.Name);
     CheckUnordered(T.String, T.UniqueName);
     CheckUnordered(T.String, T.Symbol);
     CheckUnordered(T.InternalizedString, T.Symbol);
 
     CheckSub(T.Object, T.Receiver);
     CheckSub(T.Proxy, T.Receiver);
+    CheckSub(T.Array, T.Object);
     CheckSub(T.OtherObject, T.Object);
     CheckSub(T.OtherUndetectable, T.Object);
-    CheckSub(T.OtherObject, T.Object);
 
     CheckUnordered(T.Object, T.Proxy);
+    CheckUnordered(T.Array, T.Undetectable);
     CheckUnordered(T.OtherObject, T.Undetectable);
 
     // Subtyping between concrete structural types
 
     CheckSub(T.SmiConstant, T.SignedSmall);
     CheckSub(T.SmiConstant, T.Signed32);
     CheckSub(T.SmiConstant, T.Number);
     CheckSub(T.ObjectConstant1, T.Object);
     CheckSub(T.ObjectConstant2, T.Object);
     CheckSub(T.ArrayConstant, T.Object);
-    CheckSub(T.ArrayConstant, T.OtherObject);
+    CheckSub(T.ArrayConstant, T.Array);
     CheckSub(T.ArrayConstant, T.Receiver);
     CheckSub(T.UninitializedConstant, T.Internal);
     CheckUnordered(T.ObjectConstant1, T.ObjectConstant2);
     CheckUnordered(T.ObjectConstant1, T.ArrayConstant);
     CheckUnordered(T.UninitializedConstant, T.Null);
     CheckUnordered(T.UninitializedConstant, T.Undefined);
   }
 
   void Maybe() {
     // T->Maybe(Any) iff T inhabited
@@ skipping 446 matching lines @@
 
 TEST(Union3) { Tests().Union3(); }
 
 TEST(Union4) { Tests().Union4(); }
 
 TEST(Intersect) { Tests().Intersect(); }
 
 TEST(Distributivity) { Tests().Distributivity(); }
 
 TEST(GetRange) { Tests().GetRange(); }