[heap] Turn AssertNoTypedSlotsInFreeMemory into DCHECK

After AssertNoTypedSlotsInFreeMemory being a CHECK for some time now to
get more test coverage, turn this into a DCHECK again.

This CL also renames the methods used by the sweeper to clear typed
slots in free memory. It was previously called "invalid slots" but
IMHO that could be a bit misleading, since this isn't about object slot
invalidation (where we also filter slots) but only really about slots in
free memory.

Bug: v8:12760
Change-Id: I8f414be06207460531fa54189b9ef1be85f4ecb6
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3679578Reviewed-by: Omer Katz <omerkatz@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80860}

src/heap/spaces.h

@@ -313,7 +313,7 @@ class Page : public MemoryChunk {
   ActiveSystemPages* active_system_pages() { return &active_system_pages_; }
 
   template <RememberedSetType remembered_set>
-  void ClearInvalidTypedSlots(const TypedSlotSet::FreeRangesMap& ranges) {
+  void ClearTypedSlotsInFreeMemory(const TypedSlotSet::FreeRangesMap& ranges) {
     TypedSlotSet* typed_slot_set = this->typed_slot_set<remembered_set>();
     if (typed_slot_set != nullptr) {
       typed_slot_set->ClearInvalidSlots(ranges);
@@ -321,12 +321,14 @@ class Page : public MemoryChunk {
   }
 
   template <RememberedSetType remembered_set>
-  void AssertNoInvalidTypedSlots(const TypedSlotSet::FreeRangesMap& ranges) {
-    // TODO(dinfuehr): Make this a DCHECK eventually.
+  void AssertNoTypedSlotsInFreeMemory(
+      const TypedSlotSet::FreeRangesMap& ranges) {
+#if DEBUG
     TypedSlotSet* typed_slot_set = this->typed_slot_set<OLD_TO_OLD>();
     if (typed_slot_set != nullptr) {
       typed_slot_set->AssertNoInvalidSlots(ranges);
     }
+#endif  // DEBUG
   }
 
  private:

src/heap/sweeper.cc

@@ -275,18 +275,18 @@ V8_INLINE void Sweeper::CleanupRememberedSetEntriesForFreedMemory(
   invalidated_old_to_shared_cleanup->Free(free_start, free_end);
 }
 
-void Sweeper::CleanupInvalidTypedSlotsOfFreeRanges(
+void Sweeper::CleanupTypedSlotsInFreeMemory(
     Page* page, const TypedSlotSet::FreeRangesMap& free_ranges_map,
     SweepingMode sweeping_mode) {
   if (sweeping_mode == SweepingMode::kEagerDuringGC) {
-    page->ClearInvalidTypedSlots<OLD_TO_NEW>(free_ranges_map);
+    page->ClearTypedSlotsInFreeMemory<OLD_TO_NEW>(free_ranges_map);
 
     // Typed old-to-old slot sets are only ever recorded in live code objects.
     // Also code objects are never right-trimmed, so there cannot be any slots
     // in a free range.
-    page->AssertNoInvalidTypedSlots<OLD_TO_OLD>(free_ranges_map);
+    page->AssertNoTypedSlotsInFreeMemory<OLD_TO_OLD>(free_ranges_map);
 
-    page->ClearInvalidTypedSlots<OLD_TO_SHARED>(free_ranges_map);
+    page->ClearTypedSlotsInFreeMemory<OLD_TO_SHARED>(free_ranges_map);
     return;
   }
 
@@ -294,9 +294,9 @@ void Sweeper::CleanupInvalidTypedSlotsOfFreeRanges(
 
   // After a full GC there are no old-to-new typed slots. The main thread
   // could create new slots but not in a free range.
-  page->AssertNoInvalidTypedSlots<OLD_TO_NEW>(free_ranges_map);
+  page->AssertNoTypedSlotsInFreeMemory<OLD_TO_NEW>(free_ranges_map);
   DCHECK_NULL(page->typed_slot_set<OLD_TO_OLD>());
-  page->ClearInvalidTypedSlots<OLD_TO_SHARED>(free_ranges_map);
+  page->ClearTypedSlotsInFreeMemory<OLD_TO_SHARED>(free_ranges_map);
 }
 
 void Sweeper::ClearMarkBitsAndHandleLivenessStatistics(Page* page,
@@ -420,7 +420,7 @@ int Sweeper::RawSweep(Page* p, FreeSpaceTreatmentMode free_space_treatment_mode,
   }
 
   // Phase 3: Post process the page.
-  CleanupInvalidTypedSlotsOfFreeRanges(p, free_ranges_map, sweeping_mode);
+  CleanupTypedSlotsInFreeMemory(p, free_ranges_map, sweeping_mode);
   ClearMarkBitsAndHandleLivenessStatistics(p, live_bytes);
 
   if (active_system_pages_after_sweeping) {

src/heap/sweeper.h

@@ -141,7 +141,7 @@ class Sweeper {
 
   // Helper function for RawSweep. Clears invalid typed slots in the given free
   // ranges.
-  void CleanupInvalidTypedSlotsOfFreeRanges(
+  void CleanupTypedSlotsInFreeMemory(
       Page* page, const TypedSlotSet::FreeRangesMap& free_ranges_map,
       SweepingMode sweeping_mode);