Serializer: fix false negative in hashmap lookups.

src/serialize.h

 // 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.
 
 #ifndef V8_SERIALIZE_H_
 #define V8_SERIALIZE_H_
 
 #include "src/hashmap.h"
 #include "src/heap-profiler.h"
 #include "src/isolate.h"
@@ skipping 132 matching lines @@
 class AddressMapBase {
  protected:
   static void SetValue(HashMap::Entry* entry, uint32_t v) {
     entry->value = reinterpret_cast<void*>(v);
   }
 
   static uint32_t GetValue(HashMap::Entry* entry) {
     return static_cast<uint32_t>(reinterpret_cast<intptr_t>(entry->value));
   }
 
-  static HashMap::Entry* LookupEntry(HashMap* map, HeapObject* obj,
-                                     bool insert) {
+  inline static HashMap::Entry* LookupEntry(HashMap* map, HeapObject* obj,
+                                            bool insert) {
     return map->Lookup(Key(obj), Hash(obj), insert);
   }
 
  private:
   static uint32_t Hash(HeapObject* obj) {
     return static_cast<int32_t>(reinterpret_cast<intptr_t>(obj->address()));
   }
 
   static void* Key(HeapObject* obj) {
     return reinterpret_cast<void*>(obj->address());
@@ skipping 23 matching lines @@
 
 class PartialCacheIndexMap : public AddressMapBase {
  public:
   PartialCacheIndexMap() : map_(HashMap::PointersMatch) {}
 
   static const int kInvalidIndex = -1;
 
   // Lookup object in the map. Return its index if found, or create
   // a new entry with new_index as value, and return kInvalidIndex.
   int LookupOrInsert(HeapObject* obj, int new_index) {
-    HashMap::Entry* entry = LookupEntry(&map_, obj, true);
-    if (entry->value != NULL) return GetValue(entry);
-    SetValue(entry, static_cast<uint32_t>(new_index));
+    HashMap::Entry* entry = LookupEntry(&map_, obj, false);
+    if (entry != NULL) return GetValue(entry);
+    SetValue(LookupEntry(&map_, obj, true), static_cast<uint32_t>(new_index));
     return kInvalidIndex;
   }
 
  private:
   HashMap map_;
 
   DISALLOW_COPY_AND_ASSIGN(PartialCacheIndexMap);
 };
 
 
@@ skipping 810 matching lines @@
       kNumInternalizedStringsOffset + kInt32Size;
   static const int kNumCodeStubKeysOffset = kNumReservationsOffset + kInt32Size;
   static const int kPayloadLengthOffset = kNumCodeStubKeysOffset + kInt32Size;
   static const int kChecksum1Offset = kPayloadLengthOffset + kInt32Size;
   static const int kChecksum2Offset = kChecksum1Offset + kInt32Size;
   static const int kHeaderSize = kChecksum2Offset + kInt32Size;
 };
 } }  // namespace v8::internal
 
 #endif  // V8_SERIALIZE_H_