HeapProfiler doesn't track array movements when it is shifting.

src/builtins.cc

 // 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 15 matching lines @@
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "v8.h"
 
 #include "api.h"
 #include "arguments.h"
 #include "bootstrapper.h"
 #include "builtins.h"
 #include "gdb-jit.h"
 #include "ic-inl.h"
+#include "heap-profiler.h"
 #include "mark-compact.h"
 #include "vm-state-inl.h"
 
 namespace v8 {
 namespace internal {
 
 namespace {
 
 // Arguments object passed to C++ builtins.
 template <BuiltinExtraArguments extra_args>
@@ skipping 327 matching lines @@
   former_start[to_trim + 1] = Smi::FromInt(len - to_trim);
 
   // Maintain marking consistency for HeapObjectIterator and
   // IncrementalMarking.
   int size_delta = to_trim * kPointerSize;
   if (heap->marking()->TransferMark(elms->address(),
                                     elms->address() + size_delta)) {
     MemoryChunk::IncrementLiveBytesFromMutator(elms->address(), -size_delta);
   }
 
+  HEAP_PROFILE(heap, ObjectMoveEvent(elms->address(),
+                                     elms->address() + size_delta));
   return FixedArray::cast(HeapObject::FromAddress(
       elms->address() + to_trim * kPointerSize));
 }
 
 
 static bool ArrayPrototypeHasNoElements(Heap* heap,
                                         Context* global_context,
                                         JSObject* array_proto) {
   // This method depends on non writability of Object and Array prototype
   // fields.
@@ skipping 1339 matching lines @@
   return Handle<Code>(code_address);                        \
 }
 BUILTIN_LIST_C(DEFINE_BUILTIN_ACCESSOR_C)
 BUILTIN_LIST_A(DEFINE_BUILTIN_ACCESSOR_A)
 BUILTIN_LIST_DEBUG_A(DEFINE_BUILTIN_ACCESSOR_A)
 #undef DEFINE_BUILTIN_ACCESSOR_C
 #undef DEFINE_BUILTIN_ACCESSOR_A
 
 
 } }  // namespace v8::internal