Track code cache reject reason via histogram buckets.

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 931 matching lines @@
 
   Vector<const Reservation> Reservations() const;
   Vector<const byte> Payload() const;
 
   int NumInternalizedStrings() const;
   Vector<const uint32_t> CodeStubKeys() const;
 
  private:
   explicit SerializedCodeData(ScriptData* data);
 
-  bool IsSane(String* source) const;
+  enum SanityCheckResult {
+    CHECK_SUCCESS = 0,
+    MAGIC_NUMBER_MISMATCH = 1,
+    VERSION_MISMATCH = 2,
+    SOURCE_MISMATCH = 3,
+    CPU_FEATURES_MISMATCH = 4,
+    FLAGS_MISMATCH = 5,
+    CHECKSUM_MISMATCH = 6,
+  };
+
+  SanityCheckResult SanityCheck(String* source) const;
 
   uint32_t SourceHash(String* source) const { return source->length(); }
 
+  static const uint32_t kMagicNumber = 0xC0D1F1ED;
+
   // The data header consists of uint32_t-sized entries:
-  // [0] version hash
-  // [1] source hash
-  // [2] cpu features
-  // [3] flag hash
-  // [4] number of internalized strings
-  // [5] number of code stub keys
-  // [6] number of reservation size entries
-  // [7] payload length
-  // [8] payload checksum part 1
-  // [9] payload checksum part 2
-  // ... reservations
-  // ... code stub keys
-  // ... serialized payload
-  static const int kVersionHashOffset = 0;
+  // [ 0] magic number
+  // [ 1] version hash
+  // [ 2] source hash
+  // [ 3] cpu features
+  // [ 4] flag hash
+  // [ 5] number of internalized strings
+  // [ 6] number of code stub keys
+  // [ 7] number of reservation size entries
+  // [ 8] payload length
+  // [ 9] payload checksum part 1
+  // [10] payload checksum part 2
+  // ...  reservations
+  // ...  code stub keys
+  // ...  serialized payload
+  static const int kMagicNumberOffset = 0;
+  static const int kVersionHashOffset = kMagicNumberOffset + kInt32Size;
   static const int kSourceHashOffset = kVersionHashOffset + kInt32Size;
   static const int kCpuFeaturesOffset = kSourceHashOffset + kInt32Size;
   static const int kFlagHashOffset = kCpuFeaturesOffset + kInt32Size;
   static const int kNumInternalizedStringsOffset = kFlagHashOffset + kInt32Size;
   static const int kNumReservationsOffset =
       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_