removed some unnecessary stuff from d8's initialization

src/d8.cc

Index: src/d8.cc
diff --git a/src/d8.cc b/src/d8.cc
index 56a43ad2411e375f529beca5a62dd6c2df5469ac..970e937b6d31997ec40bf3abe9eca2471821a679 100644
--- a/src/d8.cc
+++ b/src/d8.cc
@@ -490,6 +490,17 @@ void Shell::InstallUtilityScript() {
   Locker lock;
   HandleScope scope;
   Context::Scope utility_scope(utility_context_);
+
+#ifdef ENABLE_DEBUGGER_SUPPORT
+  // Install the debugger object in the utility scope
+  i::Debug* debug = i::Isolate::Current()->debug();
+  debug->Load();
+  i::Handle<i::JSObject> js_debug
+      = i::Handle<i::JSObject>(debug->debug_context()->global());
+  utility_context_->Global()->Set(String::New("$debug"),
+                                  Utils::ToLocal(js_debug));
+#endif
+

[Yang, 2011/06/21 02:25:55]

This method is called only when using interactive shell, therefore expose debug
as $debug object in the utility context here.

On a side note: how do you access an object with an identifier such as "$debug"?

[Søren Thygesen Gjesse, 2011/06/21 07:31:06]

$debug is a legal identifier, see d8.js where it is used.

   // Run the d8 shell utility script in the utility context
   int source_index = i::NativesCollection<i::D8>::GetIndex("d8");
   i::Vector<const char> shell_source =
@@ -585,7 +596,7 @@ Handle<ObjectTemplate> Shell::CreateGlobalTemplate() {
   return global_template;
 }
 
-void Shell::Initialize() {
+void Shell::Initialize(bool shell) {

[Søren Thygesen Gjesse, 2011/06/21 07:31:06]

Rename shell to interactive?

 #ifdef COMPRESS_STARTUP_DATA_BZ2
   BZip2Decompressor startup_data_decompressor;
   int bz2_result = startup_data_decompressor.Decompress();
@@ -604,24 +615,13 @@ void Shell::Initialize() {
     V8::SetCreateHistogramFunction(CreateHistogram);
     V8::SetAddHistogramSampleFunction(AddHistogramSample);
   }
-
-  // Initialize the global objects
-  HandleScope scope;
-  Handle<ObjectTemplate> global_template = CreateGlobalTemplate();
-
-  utility_context_ = Context::New(NULL, global_template);
-  utility_context_->SetSecurityToken(Undefined());
-  Context::Scope utility_scope(utility_context_);
-
-#ifdef ENABLE_DEBUGGER_SUPPORT
-  // Install the debugger object in the utility scope
-  i::Debug* debug = i::Isolate::Current()->debug();
-  debug->Load();
-  i::Handle<i::JSObject> js_debug
-      = i::Handle<i::JSObject>(debug->debug_context()->global());
-  utility_context_->Global()->Set(String::New("$debug"),
-                                  Utils::ToLocal(js_debug));
-#endif
+  if (shell) {
+    Locker lock;
+    HandleScope scope;
+    Handle<ObjectTemplate> global_template = CreateGlobalTemplate();
+    utility_context_ = Context::New(NULL, global_template);
+    utility_context_->SetSecurityToken(Undefined());
+  }

[Yang, 2011/06/21 02:25:55]

Only initialize utility context if an interactive shell is expected.

 }
 
 
@@ -637,7 +637,8 @@ void Shell::RenewEvaluationContext() {
   evaluation_context_ = Context::New(NULL, global_template);
   evaluation_context_->SetSecurityToken(Undefined());

[Søren Thygesen Gjesse, 2011/06/21 07:31:06]

If we don't set the security token for the evaluation context can't we then
avoid checking for flag --expose-debug-as below and changing the security
context of the debugger - at lease in the case of running non-interactively?

For the interactive case we might need to do something to set the security token
to the same value in all the contexts.

 
-  Context::Scope utility_scope(utility_context_);
+  Context::Scope utility_scope(evaluation_context_);
+
   i::JSArguments js_args = i::FLAG_js_arguments;
   i::Handle<i::FixedArray> arguments_array =
       FACTORY->NewFixedArray(js_args.argc());
@@ -652,11 +653,12 @@ void Shell::RenewEvaluationContext() {
                                      Utils::ToLocal(arguments_jsarray));
 
 #ifdef ENABLE_DEBUGGER_SUPPORT
-  i::Debug* debug = i::Isolate::Current()->debug();
-  debug->Load();
-
-  // Set the security token of the debug context to allow access.
-  debug->debug_context()->set_security_token(HEAP->undefined_value());
+  if (i::FLAG_expose_debug_as != NULL) {

[Yang, 2011/06/21 02:25:55]

If the debug object is not exposed, there is no point allowing access. The
premature debug->Load() is hurting d8's initialization time the most. In the
majority of the test scripts the debug object is not needed, yet this line
always loads the debug object, which takes a comparatively long time.

+    i::Debug* debug = i::Isolate::Current()->debug();
+    debug->Load();

[Søren Thygesen Gjesse, 2011/06/21 07:31:06]

If --expose-debug-as is specified the debugger is already loaded - you could
just assert that the debugger context is there.

+    // Set the security token of the debug context to allow access.
+    debug->debug_context()->set_security_token(HEAP->undefined_value());
+  }
 
   // Start the debugger agent if requested.
   if (i::FLAG_debugger_agent) {
@@ -943,7 +945,7 @@ int Shell::Main(int argc, char* argv[]) {
 
   v8::V8::SetFlagsFromCommandLine(&argc, argv, true);
 
-  Initialize();
+  Initialize(run_shell);

[Søren Thygesen Gjesse, 2011/06/21 07:31:06]

I think it will be better to have a flag for running tests (e.g. --test-shell)
instead of relying on the --shell flag. You might otherwise want to run scripts
which relies on the utility context being loaded.

 
   int result = 0;
   if (FLAG_stress_opt || FLAG_stress_deopt) {