[heap] MinorMC: Only iterate new space global handles for ptr updates

src/heap/mark-compact.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/heap/mark-compact.h"
 
 #include "src/base/atomicops.h"
 #include "src/base/bits.h"
 #include "src/base/sys-info.h"
 #include "src/code-stubs.h"
@@ skipping 4383 matching lines @@
 void MinorMarkCompactCollector::UpdatePointersAfterEvacuation() {
   TRACE_GC(heap()->tracer(), GCTracer::Scope::MC_EVACUATE_UPDATE_POINTERS);
 
   PointersUpdatingVisitor updating_visitor;
 
   {
     TRACE_GC(heap()->tracer(),
              GCTracer::Scope::MC_EVACUATE_UPDATE_POINTERS_TO_NEW);
     UpdateToSpacePointersInParallel(heap_, &page_parallel_job_semaphore_,
                                     *this);
-    // TODO(mlippautz): Iteration mode is not optimal as we process all
-    // global handles. Find a way to only process the ones related to new
-    // space.
-    heap_->IterateRoots(&updating_visitor, VISIT_ALL_IN_SWEEP_NEWSPACE);
+    heap_->IterateRoots(&updating_visitor, VISIT_ALL_IN_MINOR_MC_UPDATE);
     UpdatePointersInParallel<OLD_TO_NEW>(heap_, &page_parallel_job_semaphore_,
                                          this);
   }
 
   {
     TRACE_GC(heap()->tracer(),
              GCTracer::Scope::MC_EVACUATE_UPDATE_POINTERS_WEAK);
 
     EvacuationWeakObjectRetainer evacuation_object_retainer;
     heap()->ProcessWeakListRoots(&evacuation_object_retainer);
@@ skipping 220 matching lines @@
       // The target is always in old space, we don't have to record the slot in
       // the old-to-new remembered set.
       DCHECK(!heap()->InNewSpace(target));
       RecordRelocSlot(host, &rinfo, target);
     }
   }
 }
 
 }  // namespace internal
 }  // namespace v8