Track JS allocations as they arrive with no affection on performance when tracking is switched off

test/cctest/test-heap.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
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 // modification, are permitted provided that the following conditions are
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 //
 //     * Redistributions of source code must retain the above copyright
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@@ skipping 3211 matching lines @@
 
 
 TEST(Regress169928) {
   i::FLAG_allow_natives_syntax = true;
   i::FLAG_crankshaft = false;
   CcTest::InitializeVM();
   Isolate* isolate = CcTest::i_isolate();
   Factory* factory = isolate->factory();
   v8::HandleScope scope(CcTest::isolate());
 
+  HeapObjectsTracker tracker;

[Hannes Payer (out of office), 2013/10/02 18:00:29]

Why is that here?

[Alexandra Mikhaylova, 2013/10/03 16:27:55]

I used HeapObjectsTracker here to find some untracked allocations that occur
during this test. In fact, HeapObjectsTracker can be used in all tests where JS
allocations are performed.
I've removed it here now as there's a special test for it.

+
   // Some flags turn Scavenge collections into Mark-sweep collections
   // and hence are incompatible with this test case.
   if (FLAG_gc_global || FLAG_stress_compaction) return;
 
   // Prepare the environment
   CompileRun("function fastliteralcase(literal, value) {"
              "    literal[0] = value;"
              "    return literal;"
              "}"
              "function get_standard_literal() {"
@@ skipping 198 matching lines @@
              "    var a = new Array(n);"
              "    for (var i = 0; i < n; i += 100) a[i] = i;"
              "};"
              "f(10 * 1024 * 1024);");
   IncrementalMarking* marking = CcTest::heap()->incremental_marking();
   if (marking->IsStopped()) marking->Start();
   // This big step should be sufficient to mark the whole array.
   marking->Step(100 * MB, IncrementalMarking::NO_GC_VIA_STACK_GUARD);
   ASSERT(marking->IsComplete());
 }