Decouple root visitors from object visitors.

src/heap/object-stats.cc

 // Copyright 2015 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/object-stats.h"
 
 #include "src/assembler-inl.h"
 #include "src/compilation-cache.h"
 #include "src/counters.h"
 #include "src/heap/heap-inl.h"
@@ skipping 253 matching lines @@
   if (obj->IsJSWeakCollection()) {
     RecordJSWeakCollectionDetails(JSWeakCollection::cast(obj));
   }
   if (obj->IsJSCollection()) {
     RecordJSCollectionDetails(JSObject::cast(obj));
   }
   if (obj->IsJSFunction()) RecordJSFunctionDetails(JSFunction::cast(obj));
   if (obj->IsScript()) RecordScriptDetails(Script::cast(obj));
 }
 
-class ObjectStatsCollector::CompilationCacheTableVisitor
-    : public ObjectVisitor {
+class ObjectStatsCollector::CompilationCacheTableVisitor : public RootVisitor {
  public:
   explicit CompilationCacheTableVisitor(ObjectStatsCollector* parent)
       : parent_(parent) {}
 
-  void VisitPointers(Object** start, Object** end) override {
+  void VisitRootPointers(Root root, Object** start, Object** end) override {
     for (Object** current = start; current < end; current++) {
       HeapObject* obj = HeapObject::cast(*current);
       if (obj->IsUndefined(parent_->heap_->isolate())) continue;
       CHECK(obj->IsCompilationCacheTable());
       parent_->RecordHashTableHelper(nullptr, CompilationCacheTable::cast(obj),
                                      COMPILATION_CACHE_TABLE_SUB_TYPE);
     }
   }
 
  private:
@@ skipping 289 matching lines @@
                           SLOW_TEMPLATE_INSTANTIATIONS_CACHE_SUB_TYPE);
     FixedArray* fast_cache = native_ctx->fast_template_instantiations_cache();
     stats_->RecordFixedArraySubTypeStats(
         fast_cache, FAST_TEMPLATE_INSTANTIATIONS_CACHE_SUB_TYPE,
         fast_cache->Size(), 0);
   }
 }
 
 }  // namespace internal
 }  // namespace v8