Make --always-opt also optimize top-level code.

src/hydrogen.cc

Index: src/hydrogen.cc
diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index 40f0ca4601a59e439c4f2229fabe3f4c045b3f10..0e980b24cca16d582cd9fd62e00cb0db505b8e54 100644
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -4221,6 +4221,11 @@ bool HOptimizedGraphBuilder::BuildGraph() {
     return false;
   }
 
+  if (current_info()->scope()->is_script_scope()) {
+    Bailout(kScriptContext);
+    return false;

[Toon Verwaest, 2015/04/07 20:55:05]

Doesn't this entirely disable top-level OSR?

If I'm not mistaken (didn't bisect), it seems like this is causing a large
sunspider-bitwise-and regression; 2.1 -> 8.9ms.

[Michael Starzinger, 2015/04/07 23:01:03]

It might be that this needs to be guarded by an additional "heap_slots > 0"
check, I will investigate this tomorrow. Thanks for pointing this out.

[Michael Starzinger, 2015/04/08 12:29:18]

For the record, addressed by: https://codereview.chromium.org/1063373003/

+  }
+
   Scope* scope = current_info()->scope();
   SetUpScope(scope);
 
@@ -11436,7 +11441,7 @@ void HOptimizedGraphBuilder::VisitFunctionDeclaration(
 
 void HOptimizedGraphBuilder::VisitModuleDeclaration(
     ModuleDeclaration* declaration) {
-  UNREACHABLE();
+  return Bailout(kModuleDeclaration);
 }