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

src/x64/macro-assembler-x64.h

 // 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 1097 matching lines @@
                 Label* gc_required,
                 AllocationFlags flags);
 
   void Allocate(Register object_size,
                 Register result,
                 Register result_end,
                 Register scratch,
                 Label* gc_required,
                 AllocationFlags flags);
 
+  // Record a JS object allocation if allocations tracking mode is on.
+  void RecordObjectAllocation(Isolate* isolate,
+                              Register object,
+                              Register object_size);
+
+  void RecordObjectAllocation(Isolate* isolate,
+                              Register object,
+                              int object_size);
+
   // Undo allocation in new space. The object passed and objects allocated after
   // it will no longer be allocated. Make sure that no pointers are left to the
   // object(s) no longer allocated as they would be invalid when allocation is
   // un-done.
   void UndoAllocationInNewSpace(Register object);
 
   // Allocate a heap number in new space with undefined value. Returns
   // tagged pointer in result register, or jumps to gc_required if new
   // space is full.
   void AllocateHeapNumber(Register result,
@@ skipping 455 matching lines @@
     masm->popfq();                                                           \
   }                                                                          \
   masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_MACRO_ASSEMBLER_X64_H_