diff --git a/src/heap/incremental-marking.cc b/src/heap/incremental-marking.cc
index 376e848..c250b90 100644
--- a/src/heap/incremental-marking.cc
+++ b/src/heap/incremental-marking.cc
@@ -279,7 +279,7 @@
   if (IsMarking() && Marking::IsBlack(Marking::MarkBitFrom(object))) {
     Page* page = Page::FromAddress(object->address());
     if ((page->owner() != nullptr) && (page->owner()->identity() == LO_SPACE)) {
-      // IterateBlackObject requires us to visit the hole object.
+      // IterateBlackObject requires us to visit the whole object.
       page->ResetProgressBar();
     }
     IncrementalMarkingMarkingVisitor::IterateBody(object->map(), object);
@@ -353,7 +353,7 @@
     NewSpace* space) {
   NewSpacePageIterator it(space);
   while (it.has_next()) {
-    NewSpacePage* p = it.next();
+    Page* p = it.next();
     SetNewSpacePageFlags(p, false);
   }
 }
@@ -366,7 +366,7 @@
   DeactivateIncrementalWriteBarrierForSpace(heap_->new_space());
 
   LargePage* lop = heap_->lo_space()->first_page();
-  while (lop->is_valid()) {
+  while (LargePage::IsValid(lop)) {
     SetOldSpacePageFlags(lop, false, false);
     lop = lop->next_page();
   }
@@ -385,7 +385,7 @@
 void IncrementalMarking::ActivateIncrementalWriteBarrier(NewSpace* space) {
   NewSpacePageIterator it(space->ToSpaceStart(), space->ToSpaceEnd());
   while (it.has_next()) {
-    NewSpacePage* p = it.next();
+    Page* p = it.next();
     SetNewSpacePageFlags(p, true);
   }
 }
@@ -398,7 +398,7 @@
   ActivateIncrementalWriteBarrier(heap_->new_space());
 
   LargePage* lop = heap_->lo_space()->first_page();
-  while (lop->is_valid()) {
+  while (LargePage::IsValid(lop)) {
     SetOldSpacePageFlags(lop, true, is_compacting_);
     lop = lop->next_page();
   }
@@ -558,12 +558,6 @@
   heap_->CompletelyClearInstanceofCache();
   heap_->isolate()->compilation_cache()->MarkCompactPrologue();
 
-  if (FLAG_cleanup_code_caches_at_gc) {
-    // We will mark cache black with a separate pass
-    // when we finish marking.
-    MarkObjectGreyDoNotEnqueue(heap_->polymorphic_code_cache());
-  }
-
   // Mark strong roots grey.
   IncrementalMarkingRootMarkingVisitor visitor(this);
   heap_->IterateStrongRoots(&visitor, VISIT_ONLY_STRONG);
@@ -605,6 +599,7 @@
 
 
 void IncrementalMarking::MarkObjectGroups() {
+  DCHECK(!heap_->UsingEmbedderHeapTracer());
   DCHECK(!finalize_marking_completed_);
   DCHECK(IsMarking());
 
@@ -735,7 +730,9 @@
   // 4) Remove weak cell with live values from the list of weak cells, they
   // do not need processing during GC.
   MarkRoots();
-  MarkObjectGroups();
+  if (!heap_->UsingEmbedderHeapTracer()) {
+    MarkObjectGroups();
+  }
   if (incremental_marking_finalization_rounds_ == 0) {
     // Map retaining is needed for perfromance, not correctness,
     // so we can do it only once at the beginning of the finalization.
@@ -932,13 +929,6 @@
     }
   }
 
-  if (FLAG_cleanup_code_caches_at_gc) {
-    PolymorphicCodeCache* poly_cache = heap_->polymorphic_code_cache();
-    Marking::GreyToBlack(Marking::MarkBitFrom(poly_cache));
-    MemoryChunk::IncrementLiveBytesFromGC(poly_cache,
-                                          PolymorphicCodeCache::kSize);
-  }
-
   Object* context = heap_->native_contexts_list();
   while (!context->IsUndefined()) {
     // GC can happen when the context is not fully initialized,
@@ -952,7 +942,7 @@
         MemoryChunk::IncrementLiveBytesFromGC(cache, cache->Size());
       }
     }
-    context = Context::cast(context)->get(Context::NEXT_CONTEXT_LINK);
+    context = Context::cast(context)->next_context_link();
   }
 }
 
@@ -1130,6 +1120,18 @@
   }
 }
 
+void IncrementalMarking::FinalizeSweeping() {
+  DCHECK(state_ == SWEEPING);
+  if (heap_->mark_compact_collector()->sweeping_in_progress() &&
+      (heap_->mark_compact_collector()->sweeper().IsSweepingCompleted() ||
+       !FLAG_concurrent_sweeping)) {
+    heap_->mark_compact_collector()->EnsureSweepingCompleted();
+  }
+  if (!heap_->mark_compact_collector()->sweeping_in_progress()) {
+    bytes_scanned_ = 0;
+    StartMarking();
+  }
+}
 
 intptr_t IncrementalMarking::Step(intptr_t allocated_bytes,
                                   CompletionAction action,
@@ -1179,17 +1181,11 @@
 
     bytes_scanned_ += bytes_to_process;
 
+    // TODO(hpayer): Do not account for sweeping finalization while marking.
     if (state_ == SWEEPING) {
-      if (heap_->mark_compact_collector()->sweeping_in_progress() &&
-          (heap_->mark_compact_collector()->IsSweepingCompleted() ||
-           !FLAG_concurrent_sweeping)) {
-        heap_->mark_compact_collector()->EnsureSweepingCompleted();
-      }
-      if (!heap_->mark_compact_collector()->sweeping_in_progress()) {
-        bytes_scanned_ = 0;
-        StartMarking();
-      }
+      FinalizeSweeping();
     }
+
     if (state_ == MARKING) {
       bytes_processed = ProcessMarkingDeque(bytes_to_process);
       if (heap_->mark_compact_collector()->marking_deque()->IsEmpty()) {