Index: src/serialize.cc |
diff --git a/src/serialize.cc b/src/serialize.cc |
index 673c01f56799d997aa9e67d48afd3a318fb7b5a7..29c3005f3ec95a9d8470a14c05925b873996ba0b 100644 |
--- a/src/serialize.cc |
+++ b/src/serialize.cc |
@@ -2157,6 +2157,10 @@ void Serializer::Pad() { |
for (unsigned i = 0; i < sizeof(int32_t) - 1; i++) { |
sink_->Put(kNop, "Padding"); |
} |
+ // Pad up to pointer size for checksum. |
+ while (!IsAligned(sink_->Position(), kPointerAlignment)) { |
+ sink_->Put(kNop, "Padding"); |
+ } |
} |
@@ -2482,6 +2486,41 @@ Vector<const byte> SnapshotData::Payload() const { |
} |
+class Checksum { |
+ public: |
+ explicit Checksum(Vector<const byte> payload) { |
+ // Fletcher's checksum. Modified to reduce 64-bit sums to 32-bit. |
+ uintptr_t a = 1; |
+ uintptr_t b = 0; |
+ const uintptr_t* cur = reinterpret_cast<const uintptr_t*>(payload.start()); |
+ DCHECK(IsAligned(payload.length(), kIntptrSize)); |
+ const uintptr_t* end = cur + payload.length() / kIntptrSize; |
+ while (cur < end) { |
+ // Unsigned overflow expected and intended. |
+ a += *cur++; |
+ b += a; |
+ } |
+#if V8_HOST_ARCH_64_BIT |
+ a ^= a >> 32; |
+ b ^= b >> 32; |
+#endif // V8_HOST_ARCH_64_BIT |
+ a_ = static_cast<uint32_t>(a); |
+ b_ = static_cast<uint32_t>(b); |
+ } |
+ |
+ bool Check(uint32_t a, uint32_t b) const { return a == a_ && b == b_; } |
+ |
+ uint32_t a() const { return a_; } |
+ uint32_t b() const { return b_; } |
+ |
+ private: |
+ uint32_t a_; |
+ uint32_t b_; |
+ |
+ DISALLOW_COPY_AND_ASSIGN(Checksum); |
+}; |
+ |
+ |
SerializedCodeData::SerializedCodeData(const List<byte>& payload, |
const CodeSerializer& cs) { |
DisallowHeapAllocation no_gc; |
@@ -2510,6 +2549,10 @@ SerializedCodeData::SerializedCodeData(const List<byte>& payload, |
SetHeaderValue(kNumCodeStubKeysOffset, num_stub_keys); |
SetHeaderValue(kPayloadLengthOffset, payload.length()); |
+ Checksum checksum(payload.ToConstVector()); |
+ SetHeaderValue(kChecksum1Offset, checksum.a()); |
+ SetHeaderValue(kChecksum2Offset, checksum.b()); |
+ |
// Copy reservation chunk sizes. |
CopyBytes(data_ + kHeaderSize, reinterpret_cast<byte*>(reservations.begin()), |
reservation_size); |
@@ -2524,13 +2567,14 @@ SerializedCodeData::SerializedCodeData(const List<byte>& payload, |
} |
-bool SerializedCodeData::IsSane(String* source) { |
+bool SerializedCodeData::IsSane(String* source) const { |
return GetHeaderValue(kVersionHashOffset) == Version::Hash() && |
GetHeaderValue(kSourceHashOffset) == SourceHash(source) && |
GetHeaderValue(kCpuFeaturesOffset) == |
static_cast<uint32_t>(CpuFeatures::SupportedFeatures()) && |
GetHeaderValue(kFlagHashOffset) == FlagList::Hash() && |
- Payload().length() >= SharedFunctionInfo::kSize; |
+ Checksum(Payload()).Check(GetHeaderValue(kChecksum1Offset), |
+ GetHeaderValue(kChecksum2Offset)); |
} |