[debug] implement intuitive semantics for stepping over await call.

src/debug/debug.h

 // 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.
 
 #ifndef V8_DEBUG_DEBUG_H_
 #define V8_DEBUG_DEBUG_H_
 
 #include "src/allocation.h"
 #include "src/arguments.h"
 #include "src/assembler.h"
@@ skipping 438 matching lines @@
   void ClearBreakPoint(Handle<Object> break_point_object);
   void ClearAllBreakPoints();
   void FloodWithOneShot(Handle<JSFunction> function,
                         BreakLocatorType type = ALL_BREAK_LOCATIONS);
   void ChangeBreakOnException(ExceptionBreakType type, bool enable);
   bool IsBreakOnException(ExceptionBreakType type);
 
   // Stepping handling.
   void PrepareStep(StepAction step_action);
   void PrepareStepIn(Handle<JSFunction> function);
+  void PrepareStepInSuspendedGenerator();
   void PrepareStepOnThrow();
   void ClearStepping();
   void ClearStepOut();
   void EnableStepIn();
 
   bool PrepareFunctionForBreakPoints(Handle<SharedFunctionInfo> shared);
 
+  void RecordAsyncFunction(Handle<JSGeneratorObject> generator_object);
+
   // Returns whether the operation succeeded. Compilation can only be triggered
   // if a valid closure is passed as the second argument, otherwise the shared
   // function needs to be compiled already.
   bool EnsureDebugInfo(Handle<SharedFunctionInfo> shared,
                        Handle<JSFunction> function);
   void CreateDebugInfo(Handle<SharedFunctionInfo> shared);
   static Handle<DebugInfo> GetDebugInfo(Handle<SharedFunctionInfo> shared);
 
   template <typename C>
   bool CompileToRevealInnerFunctions(C* compilable);
@@ skipping 14 matching lines @@
 
   // Support for LiveEdit
   void FramesHaveBeenDropped(StackFrame::Id new_break_frame_id,
                              LiveEdit::FrameDropMode mode);
 
   // Threading support.
   char* ArchiveDebug(char* to);
   char* RestoreDebug(char* from);
   static int ArchiveSpacePerThread();
   void FreeThreadResources() { }
+  void Iterate(ObjectVisitor* v);
 
   bool CheckExecutionState(int id) {
     return is_active() && !debug_context().is_null() && break_id() != 0 &&
            break_id() == id;
   }
 
   // Flags and states.
   DebugScope* debugger_entry() {
     return reinterpret_cast<DebugScope*>(
         base::NoBarrier_Load(&thread_local_.current_debug_scope_));
@@ skipping 27 matching lines @@
   }
 
   Address after_break_target_address() {
     return reinterpret_cast<Address>(&after_break_target_);
   }
 
   Address step_in_enabled_address() {
     return reinterpret_cast<Address>(&thread_local_.step_in_enabled_);
   }
 
+  Address suspended_generator_address() {
+    return reinterpret_cast<Address>(&thread_local_.suspended_generator_);
+  }
+
   StepAction last_step_action() { return thread_local_.last_step_action_; }
 
   DebugFeatureTracker* feature_tracker() { return &feature_tracker_; }
 
  private:
   explicit Debug(Isolate* isolate);
 
   void UpdateState();
   void Unload();
   void SetNextBreakId() {
     thread_local_.break_id_ = ++thread_local_.break_count_;
   }
 
   // Check whether there are commands in the command queue.
   inline bool has_commands() const { return !command_queue_.IsEmpty(); }
   inline bool ignore_events() const { return is_suppressed_ || !is_active_; }
   inline bool break_disabled() const {
     return break_disabled_ || in_debug_event_listener_;
   }
 
+  void clear_suspended_generator() {
+    thread_local_.suspended_generator_ = Smi::FromInt(0);
+  }
+
+  bool has_suspended_generator() const {
+    return thread_local_.suspended_generator_ != Smi::FromInt(0);
+  }
+
   void OnException(Handle<Object> exception, Handle<Object> promise);
 
   // Constructors for debug event objects.
   MUST_USE_RESULT MaybeHandle<Object> MakeExecutionState();
   MUST_USE_RESULT MaybeHandle<Object> MakeBreakEvent(
       Handle<Object> break_points_hit);
   MUST_USE_RESULT MaybeHandle<Object> MakeExceptionEvent(
       Handle<Object> exception,
       bool uncaught,
       Handle<Object> promise);
@@ skipping 103 matching lines @@
     // to the next call that the embedder makes.
     bool step_in_enabled_;
 
     // Stores the way how LiveEdit has patched the stack. It is used when
     // debugger returns control back to user script.
     LiveEdit::FrameDropMode frame_drop_mode_;
 
     // Value of accumulator in interpreter frames. In non-interpreter frames
     // this value will be the hole.
     Handle<Object> return_value_;
+
+    Object* suspended_generator_;
   };
 
   // Storage location for registers when handling debug break calls
   ThreadLocal thread_local_;
 
   Isolate* isolate_;
 
   friend class Isolate;
   friend class DebugScope;
   friend class DisableBreak;
@@ skipping 97 matching lines @@
                                   Handle<Code> code);
   static bool DebugBreakSlotIsPatched(Address pc);
   static void ClearDebugBreakSlot(Isolate* isolate, Address pc);
 };
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_DEBUG_DEBUG_H_