[heap,snapshot] Replace first page size from snapshots with page trimming

src/isolate.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/isolate.h"
 
 #include <stdlib.h>
 
 #include <fstream>  // NOLINT(readability/streams)
 #include <sstream>
@@ skipping 2362 matching lines @@
     PrintF("Concurrent recompilation has been disabled for tracing.\n");
   } else if (OptimizingCompileDispatcher::Enabled()) {
     optimizing_compile_dispatcher_ = new OptimizingCompileDispatcher(this);
   }
 
   // Initialize runtime profiler before deserialization, because collections may
   // occur, clearing/updating ICs.
   runtime_profiler_ = new RuntimeProfiler(this);
 
   // If we are deserializing, read the state into the now-empty heap.
-  if (!create_heap_objects) {
-    des->Deserialize(this);
-  }
-  load_stub_cache_->Initialize();
-  store_stub_cache_->Initialize();
-  if (FLAG_ignition || serializer_enabled()) {
-    interpreter_->Initialize();
+  {
+    AlwaysAllocateScope always_allocate(this);
+
+    if (!create_heap_objects) {
+      des->Deserialize(this);
+    }
+    load_stub_cache_->Initialize();
+    store_stub_cache_->Initialize();
+    if (FLAG_ignition || serializer_enabled()) {
+      interpreter_->Initialize();
+    }
+
+    heap_.NotifyDeserializationComplete();
   }
 
   // Finish initialization of ThreadLocal after deserialization is done.
   clear_pending_exception();
   clear_pending_message();
   clear_scheduled_exception();
 
   // Deserializing may put strange things in the root array's copy of the
   // stack guard.
   heap_.SetStackLimits();
@@ skipping 10 matching lines @@
            Internals::kIsolateEmbedderDataOffset);
   CHECK_EQ(static_cast<int>(OFFSET_OF(Isolate, heap_.roots_)),
            Internals::kIsolateRootsOffset);
   CHECK_EQ(static_cast<int>(OFFSET_OF(Isolate, heap_.external_memory_)),
            Internals::kExternalMemoryOffset);
   CHECK_EQ(static_cast<int>(OFFSET_OF(Isolate, heap_.external_memory_limit_)),
            Internals::kExternalMemoryLimitOffset);
 
   time_millis_at_init_ = heap_.MonotonicallyIncreasingTimeInMs();
 
-  heap_.NotifyDeserializationComplete();
-
   if (!create_heap_objects) {
     // Now that the heap is consistent, it's OK to generate the code for the
     // deopt entry table that might have been referred to by optimized code in
     // the snapshot.
     HandleScope scope(this);
     Deoptimizer::EnsureCodeForDeoptimizationEntry(
         this, Deoptimizer::LAZY,
         ExternalReferenceTable::kDeoptTableSerializeEntryCount - 1);
   }
 
@@ skipping 725 matching lines @@
   // Then check whether this scope intercepts.
   if ((flag & intercept_mask_)) {
     intercepted_flags_ |= flag;
     return true;
   }
   return false;
 }
 
 }  // namespace internal
 }  // namespace v8