Expose more detailed memory statistics

src/heap.cc

Index: src/heap.cc
diff --git a/src/heap.cc b/src/heap.cc
index f3c53a1fe68756e9a30feb8e453fe61aef4ef04d..51a44d10d0a2c9d3aac422baf9f268c577e6ba43 100644
--- a/src/heap.cc
+++ b/src/heap.cc
@@ -440,6 +440,22 @@ void Heap::GarbageCollectionEpilogue() {
       symbol_table()->Capacity());
   isolate_->counters()->number_of_symbols()->Set(
       symbol_table()->NumberOfElements());
+
+  isolate_->counters()->new_space_bytes_used()->Set(
+      static_cast<int>(new_space()->SizeOfObjects()));
+  isolate_->counters()->old_pointer_space_bytes_used()->Set(
+      static_cast<int>(old_pointer_space()->SizeOfObjects()));
+  isolate_->counters()->old_data_space_bytes_used()->Set(
+      static_cast<int>(old_data_space()->SizeOfObjects()));
+  isolate_->counters()->code_space_bytes_used()->Set(
+      static_cast<int>(code_space()->SizeOfObjects()));
+  isolate_->counters()->map_space_bytes_used()->Set(
+      static_cast<int>(map_space()->SizeOfObjects()));
+  isolate_->counters()->cell_space_bytes_used()->Set(
+      static_cast<int>(cell_space()->SizeOfObjects()));
+  isolate_->counters()->lo_space_bytes_used()->Set(
+      static_cast<int>(lo_space()->SizeOfObjects()));
+
 #if defined(DEBUG)
   ReportStatisticsAfterGC();
 #endif  // DEBUG