[inspector] implemented blackboxing inside v8

src/objects.cc

 // Copyright 2015 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/objects.h"
 
 #include <cmath>
 #include <iomanip>
 #include <memory>
 #include <sstream>
@@ skipping 13430 matching lines @@
   shared->set_script(*script_object);
 }
 
 
 String* SharedFunctionInfo::DebugName() {
   Object* n = name();
   if (!n->IsString() || String::cast(n)->length() == 0) return inferred_name();
   return String::cast(n);
 }
 
+bool SharedFunctionInfo::DebugIsBlackboxed() {
+  if (!computed_debug_is_blackboxed()) {
+    HandleScope handle_scope(GetIsolate());
+    Handle<SharedFunctionInfo> info(this);
+    set_debug_is_blackboxed(info->GetIsolate()->debug()->IsBlackboxed(info));
+    set_computed_debug_is_blackboxed(true);

[Yang, 2017/01/23 08:48:29]

Oh yeah, this is not GC-safe. set_debug_is_blackboxed refers to 'this'. however,
since debug()->IsBlackboxed() can trigger GC, 'this' can become invalid if GC
moves the shared function info.

Can you make this method static with this signature?
static bool SharedFunctionInfo::DebugIsBlackboxed(Handle<SharedFunctionInfo>)

Then again, if we did that, why not just call Debug::IsBlackboxed from where we
need it and only store the bits on the shared function info?

[kozy, 2017/01/23 20:28:01]

Thank you! Done. I'll try to be more accurate about possible gc next time.

+  }
+  return debug_is_blackboxed();
+}
+
 bool SharedFunctionInfo::HasNoSideEffect() {
   if (!computed_has_no_side_effect()) {
     DisallowHeapAllocation not_handlified;
     Handle<SharedFunctionInfo> info(this);
     set_has_no_side_effect(DebugEvaluate::FunctionHasNoSideEffect(info));
     set_computed_has_no_side_effect(true);
   }
   return has_no_side_effect();
 }
 
@@ skipping 6603 matching lines @@
       // depend on this.
       return DICTIONARY_ELEMENTS;
     }
     DCHECK_LE(kind, LAST_ELEMENTS_KIND);
     return kind;
   }
 }
 
 }  // namespace internal
 }  // namespace v8