Do not include cached code in the start-up snapshot.

src/api.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/api.h"
 
 #include <string.h>  // For memcpy, strlen.
 #ifdef V8_USE_ADDRESS_SANITIZER
 #include <sanitizer/asan_interface.h>
 #endif  // V8_USE_ADDRESS_SANITIZER
@@ skipping 341 matching lines @@
   ScriptOrigin origin(String::NewFromUtf8(isolate, "<embedded script>"));
   ScriptCompiler::Source source(source_string, origin);
   Local<Script> script = ScriptCompiler::Compile(isolate, &source);
   if (try_catch.HasCaught()) return false;
   script->Run();
   return !try_catch.HasCaught();
 }
 
 
 StartupData V8::CreateSnapshotDataBlob(const char* custom_source) {
-  i::Isolate* internal_isolate = new i::Isolate(true);
-  Isolate* isolate = reinterpret_cast<Isolate*>(internal_isolate);
+  i::Isolate* i_isolate = new i::Isolate(true);
+  Isolate* isolate = reinterpret_cast<Isolate*>(i_isolate);
   StartupData result = {NULL, 0};
   {
     Isolate::Scope isolate_scope(isolate);
-    internal_isolate->Init(NULL);
+    i_isolate->Init(NULL);
     Persistent<Context> context;
     i::Snapshot::Metadata metadata;
     {
       HandleScope handle_scope(isolate);
       Handle<Context> new_context = Context::New(isolate);
       context.Reset(isolate, new_context);
       if (custom_source != NULL) {
         metadata.set_embeds_script(true);
         Context::Scope context_scope(new_context);
         if (!RunExtraCode(isolate, custom_source)) context.Reset();
       }
     }
     if (!context.IsEmpty()) {
       // Make sure all builtin scripts are cached.
       {
         HandleScope scope(isolate);
         for (int i = 0; i < i::Natives::GetBuiltinsCount(); i++) {
-          internal_isolate->bootstrapper()->NativesSourceLookup(i);
+          i_isolate->bootstrapper()->NativesSourceLookup(i);
         }
       }
       // If we don't do this then we end up with a stray root pointing at the
       // context even after we have disposed of the context.
-      internal_isolate->heap()->CollectAllAvailableGarbage("mksnapshot");
+      i_isolate->heap()->CollectAllAvailableGarbage("mksnapshot");
+
+      {
+        HandleScope scope(isolate);
+        // Clear code caches.
+        i_isolate->heap()->public_set_code_stubs(
+            *i::UnseededNumberDictionary::New(i_isolate, 128, i::TENURED));

[Toon Verwaest, 2015/03/09 12:32:50]

What about extracting the original constructor from CreateInitialObjects() onto
heap somewhere, and calling that? E.g., as ResetCodeCaches();

+        i_isolate->heap()->public_set_non_monomorphic_cache(
+            *i::UnseededNumberDictionary::New(i_isolate, 64, i::TENURED));
+      }
+
       i::Object* raw_context = *v8::Utils::OpenPersistent(context);
       context.Reset();
 
       i::SnapshotByteSink snapshot_sink;
-      i::StartupSerializer ser(internal_isolate, &snapshot_sink);
+      i::StartupSerializer ser(i_isolate, &snapshot_sink);
       ser.SerializeStrongReferences();
 
       i::SnapshotByteSink context_sink;
-      i::PartialSerializer context_ser(internal_isolate, &ser, &context_sink);
+      i::PartialSerializer context_ser(i_isolate, &ser, &context_sink);
       context_ser.Serialize(&raw_context);
       ser.SerializeWeakReferences();
 
       result = i::Snapshot::CreateSnapshotBlob(ser, context_ser, metadata);
     }
   }
   isolate->Dispose();
   return result;
 }
 
@@ skipping 7588 matching lines @@
   Isolate* isolate = reinterpret_cast<Isolate*>(info.GetIsolate());
   Address callback_address =
       reinterpret_cast<Address>(reinterpret_cast<intptr_t>(callback));
   VMState<EXTERNAL> state(isolate);
   ExternalCallbackScope call_scope(isolate, callback_address);
   callback(info);
 }
 
 
 } }  // namespace v8::internal