Vector ICs: Introduce an InstanceType for the type feedback vector.

test/mjsunit/compiler/stubs/floor-stub.js

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@@ skipping 28 matching lines @@
   var stub = builtins.MathFloorStub("MathFloorStub", 0);
   assertTrue(kExtraTypeFeedbackMinusZeroSentinel !==
              %FixedArrayGet(%GetTypeFeedbackVector(floorFunc),
                             kFirstSlotExtraTypeFeedbackIndex));
   assertEquals(5.0, stub(floorFunc, 4, 5.5));
   assertTrue(kExtraTypeFeedbackMinusZeroSentinel !==
              %FixedArrayGet(%GetTypeFeedbackVector(floorFunc),
                             kFirstSlotExtraTypeFeedbackIndex));
   // Executing floor such that it returns -0 should set the proper sentinel in
   // the feedback vector.
-  assertEquals(-Infinity, 1/stub(floorFunc, 4, -0));
+  var answer = stub(floorFunc, 4, -0);
+  assertEquals(-Infinity, 1/answer);
   assertEquals(kExtraTypeFeedbackMinusZeroSentinel,
                %FixedArrayGet(%GetTypeFeedbackVector(floorFunc),
                               kFirstSlotExtraTypeFeedbackIndex));
   %ClearFunctionTypeFeedback(floorFunc);
 })();