[snapshot] remove metadata field.

src/snapshot/snapshot-common.cc

 // Copyright 2006-2008 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.
 
 // The common functionality when building with or without snapshots.
 
 #include "src/snapshot/snapshot.h"
 
 #include "src/api.h"
 #include "src/base/platform/platform.h"
@@ skipping 13 matching lines @@
 #endif  // DEBUG
 
 
 bool Snapshot::HaveASnapshotToStartFrom(Isolate* isolate) {
   // Do not use snapshots if the isolate is used to create snapshots.
   return isolate->snapshot_blob() != NULL &&
          isolate->snapshot_blob()->data != NULL;
 }
 
 
-bool Snapshot::EmbedsScript(Isolate* isolate) {
-  if (!isolate->snapshot_available()) return false;
-  return ExtractMetadata(isolate->snapshot_blob()).embeds_script();
-}
-
-
 uint32_t Snapshot::SizeOfFirstPage(Isolate* isolate, AllocationSpace space) {
   DCHECK(space >= FIRST_PAGED_SPACE && space <= LAST_PAGED_SPACE);
   if (!isolate->snapshot_available()) {
     return static_cast<uint32_t>(MemoryAllocator::PageAreaSize(space));
   }
   uint32_t size;
   int offset = kFirstPageSizesOffset + (space - FIRST_PAGED_SPACE) * kInt32Size;
   memcpy(&size, isolate->snapshot_blob()->data + offset, kInt32Size);
   return size;
 }
@@ skipping 35 matching lines @@
   if (!maybe_context.ToHandle(&result)) return MaybeHandle<Context>();
   CHECK(result->IsContext());
   if (FLAG_profile_deserialization) {
     double ms = timer.Elapsed().InMillisecondsF();
     int bytes = context_data.length();
     PrintF("[Deserializing context (%d bytes) took %0.3f ms]\n", bytes, ms);
   }
   return Handle<Context>::cast(result);
 }
 
-
-void CalculateFirstPageSizes(bool is_default_snapshot,
-                             const SnapshotData& startup_snapshot,
+void CalculateFirstPageSizes(const SnapshotData& startup_snapshot,
                              const SnapshotData& context_snapshot,
                              uint32_t* sizes_out) {
   Vector<const SerializedData::Reservation> startup_reservations =
       startup_snapshot.Reservations();
   Vector<const SerializedData::Reservation> context_reservations =
       context_snapshot.Reservations();
   int startup_index = 0;
   int context_index = 0;
 
   if (FLAG_profile_deserialization) {
@@ skipping 27 matching lines @@
     if (single_chunk) {
       // If both the startup snapshot data and the context snapshot data on
       // this space fit in a single page, then we consider limiting the size
       // of the first page. For this, we add the chunk sizes and some extra
       // allowance. This way we achieve a smaller startup memory footprint.
       required = (startup_reservations[startup_index].chunk_size() +
                   2 * context_reservations[context_index].chunk_size()) +
                  Page::kObjectStartOffset;
       // Add a small allowance to the code space for small scripts.
       if (space == CODE_SPACE) required += 32 * KB;
-    } else if (!FLAG_debug_code) {
-      // We expect the vanilla snapshot to only require one page per space,
-      // unless we are emitting debug code.
-      DCHECK(!is_default_snapshot);
     }
 
     if (space >= FIRST_PAGED_SPACE && space <= LAST_PAGED_SPACE) {
       uint32_t max_size =
           MemoryAllocator::PageAreaSize(static_cast<AllocationSpace>(space));
       sizes_out[space - FIRST_PAGED_SPACE] = Min(required, max_size);
     } else {
       DCHECK(single_chunk);
     }
     startup_index++;
     context_index++;
   }
 
   DCHECK_EQ(startup_reservations.length(), startup_index);
   DCHECK_EQ(context_reservations.length(), context_index);
 }
 
-
 v8::StartupData Snapshot::CreateSnapshotBlob(
     const i::StartupSerializer& startup_ser,
-    const i::PartialSerializer& context_ser, Snapshot::Metadata metadata) {
+    const i::PartialSerializer& context_ser) {
   SnapshotData startup_snapshot(startup_ser);
   SnapshotData context_snapshot(context_ser);
   Vector<const byte> startup_data = startup_snapshot.RawData();
   Vector<const byte> context_data = context_snapshot.RawData();
 
   uint32_t first_page_sizes[kNumPagedSpaces];
 
-  CalculateFirstPageSizes(!metadata.embeds_script(), startup_snapshot,
-                          context_snapshot, first_page_sizes);
+  CalculateFirstPageSizes(startup_snapshot, context_snapshot, first_page_sizes);
 
   int startup_length = startup_data.length();
   int context_length = context_data.length();
   int context_offset = ContextOffset(startup_length);
 
   int length = context_offset + context_length;
   char* data = new char[length];
 
-  memcpy(data + kMetadataOffset, &metadata.RawValue(), kInt32Size);
   memcpy(data + kFirstPageSizesOffset, first_page_sizes,
          kNumPagedSpaces * kInt32Size);
   memcpy(data + kStartupLengthOffset, &startup_length, kInt32Size);
   memcpy(data + kStartupDataOffset, startup_data.begin(), startup_length);
   memcpy(data + context_offset, context_data.begin(), context_length);
   v8::StartupData result = {data, length};
 
   if (FLAG_profile_deserialization) {
     PrintF(
         "Snapshot blob consists of:\n"
         "%10d bytes for startup\n"
         "%10d bytes for context\n",
         startup_length, context_length);
   }
   return result;
 }
 
-
-Snapshot::Metadata Snapshot::ExtractMetadata(const v8::StartupData* data) {
-  uint32_t raw;
-  memcpy(&raw, data->data + kMetadataOffset, kInt32Size);
-  return Metadata(raw);
-}
-
-
 Vector<const byte> Snapshot::ExtractStartupData(const v8::StartupData* data) {
   DCHECK_LT(kIntSize, data->raw_size);
   int startup_length;
   memcpy(&startup_length, data->data + kStartupLengthOffset, kInt32Size);
   DCHECK_LT(startup_length, data->raw_size);
   const byte* startup_data =
       reinterpret_cast<const byte*>(data->data + kStartupDataOffset);
   return Vector<const byte>(startup_data, startup_length);
 }
 
@@ skipping 51 matching lines @@
 Vector<const byte> SnapshotData::Payload() const {
   int reservations_size = GetHeaderValue(kNumReservationsOffset) * kInt32Size;
   const byte* payload = data_ + kHeaderSize + reservations_size;
   int length = GetHeaderValue(kPayloadLengthOffset);
   DCHECK_EQ(data_ + size_, payload + length);
   return Vector<const byte>(payload, length);
 }
 
 }  // namespace internal
 }  // namespace v8