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

src/x64/macro-assembler-x64.cc

Index: src/x64/macro-assembler-x64.cc
diff --git a/src/x64/macro-assembler-x64.cc b/src/x64/macro-assembler-x64.cc
index b301f29e31f804cdca1817216414d1b3f354fa5e..b3336e6eabbce0f7b9d49033035e622b2150cc37 100644
--- a/src/x64/macro-assembler-x64.cc
+++ b/src/x64/macro-assembler-x64.cc
@@ -4093,6 +4093,10 @@ void MacroAssembler::Allocate(int object_size,
   // Load address of new object into result.
   LoadAllocationTopHelper(result, scratch, flags);
 
+  if (isolate()->heap_profiler()->is_tracking_allocations()) {
+    RecordObjectAllocation(isolate(), result, object_size);
+  }
+
   // Align the next allocation. Storing the filler map without checking top is
   // safe in new-space because the limit of the heap is aligned there.
   if (((flags & DOUBLE_ALIGNMENT) != 0) && FLAG_debug_code) {
@@ -4172,6 +4176,10 @@ void MacroAssembler::Allocate(Register object_size,
   // Load address of new object into result.
   LoadAllocationTopHelper(result, scratch, flags);
 
+  if (isolate()->heap_profiler()->is_tracking_allocations()) {
+    RecordObjectAllocation(isolate(), result, object_size);
+  }
+
   // Align the next allocation. Storing the filler map without checking top is
   // safe in new-space because the limit of the heap is aligned there.
   if (((flags & DOUBLE_ALIGNMENT) != 0) && FLAG_debug_code) {
@@ -4933,6 +4941,38 @@ void MacroAssembler::TestJSArrayForAllocationMemento(
 }
 
 
+void MacroAssembler::RecordObjectAllocation(Isolate* isolate,
+                                            Register object,
+                                            Register object_size) {
+  FrameScope frame(this, StackFrame::EXIT);
+  PushSafepointRegisters();
+  PrepareCallCFunction(3);
+  // In case object is rdx
+  movq(kScratchRegister, object);
+  movq(arg_reg_3, object_size);
+  movq(arg_reg_2, kScratchRegister);
+  movq(arg_reg_1, isolate, RelocInfo::EXTERNAL_REFERENCE);
+  CallCFunction(
+      ExternalReference::record_object_allocation_function(isolate), 3);
+  PopSafepointRegisters();
+}
+
+
+void MacroAssembler::RecordObjectAllocation(Isolate* isolate,
+                                            Register object,
+                                            int object_size) {
+  FrameScope frame(this, StackFrame::EXIT);
+  PushSafepointRegisters();
+  PrepareCallCFunction(3);
+  movq(arg_reg_2, object);
+  movq(arg_reg_3, Immediate(object_size));
+  movq(arg_reg_1, isolate, RelocInfo::EXTERNAL_REFERENCE);
+  CallCFunction(
+      ExternalReference::record_object_allocation_function(isolate), 3);
+  PopSafepointRegisters();
+}
+
+
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64