Only reference constant root list entries in the snapshot.

src/serialize.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/v8.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/base/platform/platform.h"
 #include "src/bootstrapper.h"
@@ skipping 463 matching lines @@
     DeleteArray(encodings_[type]);
   }
   DeleteArray(encodings_);
 }
 
 
 RootIndexMap::RootIndexMap(Isolate* isolate) {
   map_ = new HashMap(HashMap::PointersMatch);
   Object** root_array = isolate->heap()->roots_array_start();
   for (uint32_t i = 0; i < Heap::kStrongRootListLength; i++) {
-    Object* root = root_array[i];
-    if (root->IsHeapObject() && !isolate->heap()->InNewSpace(root)) {
+    Heap::RootListIndex root_index = static_cast<Heap::RootListIndex>(i);
+    Object* root = root_array[root_index];
+    // Omit root entries that can be written after initialization. They must
+    // not be referenced through the root list in the snapshot.
+    if (root->IsHeapObject() &&
+        isolate->heap()->RootCanBeTreatedAsConstant(root_index)) {
       HeapObject* heap_object = HeapObject::cast(root);
       HashMap::Entry* entry = LookupEntry(map_, heap_object, false);
       if (entry != NULL) {
         // Some are initialized to a previous value in the root list.
         DCHECK_LT(GetValue(entry), i);
       } else {
         SetValue(LookupEntry(map_, heap_object, true), i);
       }
     }
   }
@@ skipping 2154 matching lines @@
   DisallowHeapAllocation no_gc;
   SerializedCodeData* scd = new SerializedCodeData(cached_data);
   SanityCheckResult r = scd->SanityCheck(source);
   if (r == CHECK_SUCCESS) return scd;
   cached_data->Reject();
   source->GetIsolate()->counters()->code_cache_reject_reason()->AddSample(r);
   delete scd;
   return NULL;
 }
 } }  // namespace v8::internal