Pretenure call new support.

test/mjsunit/array-constructor-feedback.js

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 64 matching lines @@
 function assertKind(expected, obj, name_opt) {
   if (!support_smi_only_arrays &&
       expected == elements_kind.fast_smi_only) {
     expected = elements_kind.fast;
   }
   assertEquals(expected, getKind(obj), name_opt);
 }
 
 if (support_smi_only_arrays) {
 
-  // Test: If a call site goes megamorphic, it loses the ability to
-  // use allocation site feedback.
+  // Test: If a call site goes megamorphic, it retains the ability to
+  // use allocation site feedback (if FLAG_allocation_site_pretenuring
+  // is on).
   (function() {
     function bar(t, len) {
       return new t(len);
     }
 
     a = bar(Array, 10);
     a[0] = 3.5;
     b = bar(Array, 1);
     assertKind(elements_kind.fast_double, b);
     c = bar(Object, 3);
     b = bar(Array, 10);
-    assertKind(elements_kind.fast_smi_only, b);
-    b[0] = 3.5;
-    c = bar(Array, 10);
-    assertKind(elements_kind.fast_smi_only, c);
+    // TODO(mvstanton): re-enable when FLAG_allocation_site_pretenuring
+    // is on in the build.
+    // assertKind(elements_kind.fast_double, b);
   })();
 
 
   // Test: ensure that crankshafted array constructor sites are deopted
   // if another function is used.
   (function() {
     function bar0(t) {
       return new t();
     }
     a = bar0(Array);
     a[0] = 3.5;
     b = bar0(Array);
     assertKind(elements_kind.fast_double, b);
     %OptimizeFunctionOnNextCall(bar0);
     b = bar0(Array);
     assertKind(elements_kind.fast_double, b);
     assertOptimized(bar0);
     // bar0 should deopt
     b = bar0(Object);
     assertUnoptimized(bar0)
     // When it's re-optimized, we should call through the full stub
     bar0(Array);
     %OptimizeFunctionOnNextCall(bar0);
     b = bar0(Array);
-    // We also lost our ability to record kind feedback, as the site
-    // is megamorphic now.
-    assertKind(elements_kind.fast_smi_only, b);
-    assertOptimized(bar0);
-    b[0] = 3.5;
-    c = bar0(Array);
-    assertKind(elements_kind.fast_smi_only, c);
+    // This only makes sense to test if we allow crankshafting
+    if (4 != %GetOptimizationStatus(bar0)) {
+      // We also lost our ability to record kind feedback, as the site
+      // is megamorphic now.
+      assertKind(elements_kind.fast_smi_only, b);
+      assertOptimized(bar0);
+      b[0] = 3.5;
+      c = bar0(Array);
+      assertKind(elements_kind.fast_smi_only, c);
+    }
   })();
 
 
   // Test: Ensure that inlined array calls in crankshaft learn from deopts
   // based on the move to a dictionary for the array.
   (function() {
     function bar(len) {
       return new Array(len);
     }
     a = bar(10);
@@ skipping 100 matching lines @@
     // Try again
     %OptimizeFunctionOnNextCall(bar);
     a = bar(100);
     assertOptimized(bar);
     assertTrue(isHoley(a));
     a = bar(0);
     assertOptimized(bar);
     assertTrue(isHoley(a));
   })();
 }