Verify that source string matches serialized code.

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"
 #include "src/deoptimizer.h"
 #include "src/execution.h"
 #include "src/global-handles.h"
 #include "src/ic-inl.h"
 #include "src/natives.h"
+#include "src/objects.h"
 #include "src/runtime.h"
 #include "src/serialize.h"
 #include "src/snapshot.h"
 #include "src/snapshot-source-sink.h"
 #include "src/stub-cache.h"
 #include "src/v8threads.h"
 #include "src/version.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 1960 matching lines @@
 
   ASSERT(how_to_code == kPlain && where_to_point == kStartOfObject);
   sink_->Put(kAttachedReference + how_to_code + where_to_point, "Source");
   sink_->PutInt(kSourceObjectIndex, "kSourceObjectIndex");
 }
 
 
 Handle<SharedFunctionInfo> CodeSerializer::Deserialize(Isolate* isolate,
                                                        ScriptData* data,
                                                        Handle<String> source) {
-  SerializedCodeData scd(data);
+  SerializedCodeData scd(data, *source);
   SnapshotByteSource payload(scd.Payload(), scd.PayloadLength());
   Deserializer deserializer(&payload);
   STATIC_ASSERT(NEW_SPACE == 0);
   // TODO(yangguo) what happens if remaining new space is too small?
   for (int i = NEW_SPACE; i <= PROPERTY_CELL_SPACE; i++) {
     deserializer.set_reservation(i, scd.GetReservation(i));
   }
   DisallowHeapAllocation no_gc;
 
   // Prepare and register list of attached objects.
   Vector<Object*> attached_objects = Vector<Object*>::New(1);
   attached_objects[kSourceObjectIndex] = *source;
   deserializer.SetAttachedObjects(&attached_objects);
 
   Object* root;
   deserializer.DeserializePartial(isolate, &root);
   deserializer.FlushICacheForNewCodeObjects();
   return Handle<SharedFunctionInfo>(SharedFunctionInfo::cast(root), isolate);
 }
 
 
 SerializedCodeData::SerializedCodeData(List<byte>* payload, CodeSerializer* cs)
     : owns_script_data_(true) {
+  DisallowHeapAllocation no_gc;
   int data_length = payload->length() + kHeaderEntries * kIntSize;
   byte* data = NewArray<byte>(data_length);
   ASSERT(IsAligned(reinterpret_cast<intptr_t>(data), kPointerAlignment));
   CopyBytes(data + kHeaderEntries * kIntSize, payload->begin(),
             static_cast<size_t>(payload->length()));
   script_data_ = new ScriptData(data, data_length);
   script_data_->AcquireDataOwnership();
-  SetHeaderValue(kVersionHashOffset, Version::Hash());
+  SetHeaderValue(kCheckSumOffset, CheckSum(cs->source()));
   STATIC_ASSERT(NEW_SPACE == 0);
   for (int i = NEW_SPACE; i <= PROPERTY_CELL_SPACE; i++) {
     SetHeaderValue(kReservationsOffset + i, cs->CurrentAllocationAddress(i));
   }
 }
 
 
-bool SerializedCodeData::IsSane() {
-  return GetHeaderValue(kVersionHashOffset) == Version::Hash() &&
+bool SerializedCodeData::IsSane(String* source) {
+  return GetHeaderValue(kCheckSumOffset) == CheckSum(source) &&
          PayloadLength() >= SharedFunctionInfo::kSize;
 }
+
+
+int SerializedCodeData::CheckSum(String* string) {
+  int checksum = Version::Hash();
+#ifdef DEBUG
+  uint32_t seed = static_cast<uint32_t>(checksum);
+  checksum = static_cast<int>(IteratingStringHasher::Hash(string, seed));
+#endif  // DEBUG
+  return checksum;
+}
 } }  // namespace v8::internal