[inspector] implemented blackboxing inside v8

src/debug/debug.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/debug/debug.h"
 
 #include <memory>
 
 #include "src/api.h"
 #include "src/arguments.h"
@@ skipping 825 matching lines @@
   while (debug_info_list_ != NULL) {
     RemoveDebugInfoAndClearFromShared(debug_info_list_->debug_info());
   }
 }
 
 void Debug::FloodWithOneShot(Handle<JSFunction> function,
                              BreakLocatorType type) {
   // Debug utility functions are not subject to debugging.
   if (function->native_context() == *debug_context()) return;
 
-  if (!function->shared()->IsSubjectToDebugging()) {
+  if (!function->shared()->IsSubjectToDebugging() ||
+      function->shared()->DebugIsBlackboxed()) {
     // Builtin functions are not subject to stepping, but need to be
     // deoptimized, because optimized code does not check for debug
     // step in at call sites.
     Deoptimizer::DeoptimizeFunction(*function);
     return;
   }
   // Make sure the function is compiled and has set up the debug info.
   Handle<SharedFunctionInfo> shared(function->shared());
   if (!EnsureDebugInfo(shared, function)) {
     // Return if we failed to retrieve the debug info.
@@ skipping 98 matching lines @@
   if (last_step_action() == StepNext || last_step_action() == StepOut) {
     while (!it.done()) {
       Address current_fp = it.frame()->UnpaddedFP();
       if (current_fp >= thread_local_.target_fp_) break;
       it.Advance();
     }
   }
 
   // Find the closest Javascript frame we can flood with one-shots.
   while (!it.done() &&
-         !it.frame()->function()->shared()->IsSubjectToDebugging()) {
+         (!it.frame()->function()->shared()->IsSubjectToDebugging() ||
+          it.frame()->function()->shared()->DebugIsBlackboxed())) {

[dgozman, 2017/01/19 21:49:14]

Should we make IsSubjectToDebugging() to check for blackboxed? That could be
easier to maintain.

[kozy, 2017/01/20 02:32:37]

Acknowledged.

[Yang, 2017/01/20 09:30:48]

I think the reason we don't is because we want blackboxed functions to still
show up in the stack trace.

     it.Advance();
   }
 
   if (it.done()) return;  // No suitable Javascript catch handler.
 
   FloodWithOneShot(Handle<JSFunction>(it.frame()->function()));
 }
 
 
 void Debug::PrepareStep(StepAction step_action) {
@@ skipping 54 matching lines @@
   clear_suspended_generator();
 
   switch (step_action) {
     case StepNone:
       UNREACHABLE();
       break;
     case StepOut:
       // Advance to caller frame.
       frames_it.Advance();
       // Skip native and extension functions on the stack.
-      while (!frames_it.done() &&
-             !frames_it.frame()->function()->shared()->IsSubjectToDebugging()) {
+      while (
+          !frames_it.done() &&
+          (!frames_it.frame()->function()->shared()->IsSubjectToDebugging() ||
+           frames_it.frame()->function()->shared()->DebugIsBlackboxed())) {
         // Builtin functions are not subject to stepping, but need to be
         // deoptimized to include checks for step-in at call sites.
         Deoptimizer::DeoptimizeFunction(frames_it.frame()->function());
         frames_it.Advance();
       }
       if (!frames_it.done()) {
         // Fill the caller function to return to with one-shot break points.
         Handle<JSFunction> caller_function(frames_it.frame()->function());
         FloodWithOneShot(caller_function);
         thread_local_.target_fp_ = frames_it.frame()->UnpaddedFP();
@@ skipping 695 matching lines @@
   // Bail out if exception breaks are not active
   if (uncaught) {
     // Uncaught exceptions are reported by either flags.
     if (!(break_on_uncaught_exception_ || break_on_exception_)) return;
   } else {
     // Caught exceptions are reported is activated.
     if (!break_on_exception_) return;
   }
 
   {
-    // Check whether the break location is muted.
     JavaScriptFrameIterator it(isolate_);
-    if (!it.done() && IsMutedAtCurrentLocation(it.frame())) return;
+    // Check whether the top frame is blackboxed or the break location is muted.
+    if (!it.done() && (it.frame()->function()->shared()->DebugIsBlackboxed() ||
+                       IsMutedAtCurrentLocation(it.frame()))) {
+      return;
+    }
   }
 
   DebugScope debug_scope(this);
   if (debug_scope.failed()) return;
 
   if (debug_event_listener_) {
     HandleScope scope(isolate_);
 
     // Create the execution state.
     Handle<Object> exec_state;
@@ skipping 118 matching lines @@
   // Since we holding promise when at least one microtask is scheduled (inside
   // PromiseReactionJobInfo), we can send cancel event in weak callback.
   GlobalHandles::MakeWeak(
       global_handle.location(),
       new CollectedCallbackData(global_handle.location(), async_id->value(),
                                 this, isolate_),
       &ResetPromiseHandle, v8::WeakCallbackType::kParameter);
   return async_id->value();
 }
 
+void Debug::SetIsBlackboxedCallback(debug::IsBlackboxedCallback callback,
+                                    void* data) {
+  is_blackboxed_callback_ = callback;
+  is_blackboxed_callback_data_ = data;
+}
+
+namespace {
+debug::Location GetDebugLocation(Handle<Script> script, int source_position) {
+  Script::InitLineEnds(script);
+  int line = Script::GetLineNumber(script, source_position);

[dgozman, 2017/01/19 22:34:20]

GetPositionInfo

[kozy, 2017/01/20 02:32:37]

Done.

+  int column = Script::GetColumnNumber(script, source_position);
+  return debug::Location(line, column);
+}
+}  // namespace
+
+bool Debug::IsBlackboxed(Handle<SharedFunctionInfo> shared) {
+  if (!is_blackboxed_callback_) return false;
+  Handle<Script> script(Script::cast(shared->script()));
+  if (script->type() != i::Script::TYPE_NORMAL) return false;
+
+  debug::Location start = GetDebugLocation(script, shared->start_position());
+  debug::Location end = GetDebugLocation(script, shared->end_position());
+
+  return is_blackboxed_callback_(ToApiHandle<debug::Script>(script), start, end,
+                                 is_blackboxed_callback_data_);
+}
+
 void Debug::OnAsyncTaskEvent(debug::PromiseDebugActionType type, int id) {
   if (in_debug_scope() || ignore_events()) return;
 
   if (debug_event_listener_) {
     debug_event_listener_->PromiseEventOccurred(type, id);
     if (!non_inspector_listener_exists()) return;
   }
 
   HandleScope scope(isolate_);
   DebugScope debug_scope(this);
@@ skipping 362 matching lines @@
 
   StackLimitCheck check(isolate_);
   if (check.HasOverflowed()) return;
 
   { JavaScriptFrameIterator it(isolate_);
     DCHECK(!it.done());
     Object* fun = it.frame()->function();
     if (fun && fun->IsJSFunction()) {
       // Don't stop in builtin functions.
       if (!JSFunction::cast(fun)->shared()->IsSubjectToDebugging()) return;
+      if (isolate_->stack_guard()->CheckDebugBreak() &&
+          JSFunction::cast(fun)->shared()->DebugIsBlackboxed())
+        return;
       JSGlobalObject* global =
           JSFunction::cast(fun)->context()->global_object();
       // Don't stop in debugger functions.
       if (IsDebugGlobal(global)) return;
       // Don't stop if the break location is muted.
       if (IsMutedAtCurrentLocation(it.frame())) return;
     }
   }
 
   // Collect the break state before clearing the flags.
@@ skipping 377 matching lines @@
   logger_->DebugEvent("Put", message.text());
 }
 
 void LockingCommandMessageQueue::Clear() {
   base::LockGuard<base::Mutex> lock_guard(&mutex_);
   queue_.Clear();
 }
 
 }  // namespace internal
 }  // namespace v8