[heap] Clear out of live range remembered set slots in large objects.

src/heap/spaces.cc

Index: src/heap/spaces.cc
diff --git a/src/heap/spaces.cc b/src/heap/spaces.cc
index 4a565ac90747bea2c3f4bc4e15af1386ec13d778..5e98b826811cf022e7028d841c1fe3a88f17b34f 100644
--- a/src/heap/spaces.cc
+++ b/src/heap/spaces.cc
@@ -2923,6 +2923,19 @@ Address LargePage::GetAddressToShrink() {
   return 0;
 }
 
+void LargePage::ClearOutOfLiveRangeSlots(Address free_start) {
+  if (old_to_new_slots() != nullptr) {
+    old_to_new_slots()->RemoveRange(
+        static_cast<int>(free_start - address()),
+        static_cast<int>(free_start + size() - address()));
+  }
+  if (old_to_old_slots() != nullptr) {
+    old_to_old_slots()->RemoveRange(
+        static_cast<int>(free_start - address()),
+        static_cast<int>(free_start + size() - address()));
+  }
+}
+
 // -----------------------------------------------------------------------------
 // LargeObjectIterator
 
@@ -3083,6 +3096,7 @@ void LargeObjectSpace::FreeUnmarkedObjects() {
       Address free_start;
       if ((free_start = current->GetAddressToShrink()) != 0) {
         // TODO(hpayer): Perform partial free concurrently.
+        current->ClearOutOfLiveRangeSlots(free_start);
         heap()->memory_allocator()->PartialFreeMemory(current, free_start);
       }
       previous = current;