[heap] Avoid the use of cells to point from code to new-space objects.

src/heap/remembered-set.cc

Index: src/heap/remembered-set.cc
diff --git a/src/heap/remembered-set.cc b/src/heap/remembered-set.cc
index 403c99b05712ec53d2920b40e5ee6ff9e3a2f84c..c79871d915065c7144d706e175dc92625e6c7a9d 100644
--- a/src/heap/remembered-set.cc
+++ b/src/heap/remembered-set.cc
@@ -9,6 +9,7 @@
 #include "src/heap/slot-set.h"
 #include "src/heap/spaces.h"
 #include "src/heap/store-buffer.h"
+#include "src/macro-assembler.h"
 
 namespace v8 {
 namespace internal {
@@ -16,16 +17,38 @@ namespace internal {
 template <PointerDirection direction>
 void RememberedSet<direction>::ClearInvalidSlots(Heap* heap) {
   STATIC_ASSERT(direction == OLD_TO_NEW);
-  PageIterator it(heap->old_space());
-  MemoryChunk* chunk;
-  while (it.has_next()) {
-    chunk = it.next();
-    SlotSet* slots = GetSlotSet(chunk);
-    if (slots != nullptr) {
-      slots->Iterate([heap, chunk](Address addr) {
-        Object** slot = reinterpret_cast<Object**>(addr);
-        return IsValidSlot(heap, chunk, slot) ? KEEP_SLOT : REMOVE_SLOT;
-      });
+  {
+    PageIterator it(heap->old_space());
+    MemoryChunk* chunk;
+    while (it.has_next()) {
+      chunk = it.next();
+      {
+        SlotSet* slots = GetSlotSet(chunk);
+        if (slots != nullptr) {
+          slots->Iterate([heap, chunk](Address addr) {
+            Object** slot = reinterpret_cast<Object**>(addr);
+            return IsValidSlot(heap, chunk, slot) ? KEEP_SLOT : REMOVE_SLOT;
+          });
+        }
+      }
+    }
+  }
+  {
+    PageIterator it(heap->code_space());
+    MemoryChunk* chunk;
+    while (it.has_next()) {
+      chunk = it.next();
+      TypedSlotSet* slots = GetTypedSlotSet(chunk);
+      if (slots != nullptr) {
+        slots->Iterate(
+            [heap, chunk](SlotType type, Address host_addr, Address addr) {
+              if (Marking::IsBlack(Marking::MarkBitFrom(host_addr))) {
+                return KEEP_SLOT;
+              } else {
+                return REMOVE_SLOT;
+              }
+            });
+      }
     }
   }
 }