Introduce debug events for Microtask queue.

R=yangguo@chromium.org, adamk@chromium.org, rafaelw@chromium.org, rossberg@chromium.org
BUG=chromium:272416
LOG=Y

Review URL: https://codereview.chromium.org/362783002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22204 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

include/v8-debug.h

@@ -21,7 +21,8 @@ enum DebugEvent {
   AfterCompile  = 5,
   CompileError = 6,
   PromiseEvent = 7,
-  BreakForCommand = 8
+  AsyncTaskEvent = 8,
+  BreakForCommand = 9
 };
 
 

src/debug-debugger.js

@@ -20,7 +20,8 @@ Debug.DebugEvent = { Break: 1,
                      BeforeCompile: 4,
                      AfterCompile: 5,
                      CompileError: 6,
-                     PromiseEvent: 7 };
+                     PromiseEvent: 7,
+                     AsyncTaskEvent: 8 };
 
 // Types of exceptions that can be broken upon.
 Debug.ExceptionBreak = { Caught : 0,
@@ -1226,6 +1227,33 @@ NewPromiseEvent.prototype.resolver = function() {
 }
 
 
+function MakeAsyncTaskEvent(event_data) {
+  return new AsyncTaskEvent(event_data);
+}
+
+
+function AsyncTaskEvent(event_data) {
+  this.type_ = event_data.type;
+  this.name_ = event_data.name;
+  this.id_ = event_data.id;
+}
+
+
+AsyncTaskEvent.prototype.type = function() {
+  return this.type_;
+}
+
+
+AsyncTaskEvent.prototype.name = function() {
+  return this.name_;
+}
+
+
+AsyncTaskEvent.prototype.id = function() {
+  return this.id_;
+}
+
+
 function DebugCommandProcessor(exec_state, opt_is_running) {
   this.exec_state_ = exec_state;
   this.running_ = opt_is_running || false;

src/debug.cc

@@ -2554,6 +2554,13 @@ MaybeHandle<Object> Debug::MakePromiseEvent(Handle<JSObject> event_data) {
 }
 
 
+MaybeHandle<Object> Debug::MakeAsyncTaskEvent(Handle<JSObject> task_event) {
+  // Create the async task event object.
+  Handle<Object> argv[] = { task_event };
+  return MakeJSObject("MakeAsyncTaskEvent", ARRAY_SIZE(argv), argv);
+}
+
+
 void Debug::OnException(Handle<Object> exception, bool uncaught) {
   if (in_debug_scope() || ignore_events()) return;
 
@@ -2718,6 +2725,25 @@ void Debug::OnPromiseEvent(Handle<JSObject> data) {
 }
 
 
+void Debug::OnAsyncTaskEvent(Handle<JSObject> data) {
+  if (in_debug_scope() || ignore_events()) return;
+
+  HandleScope scope(isolate_);
+  DebugScope debug_scope(this);
+  if (debug_scope.failed()) return;
+
+  // Create the script collected state object.
+  Handle<Object> event_data;
+  // Bail out and don't call debugger if exception.
+  if (!MakeAsyncTaskEvent(data).ToHandle(&event_data)) return;
+
+  // Process debug event.
+  ProcessDebugEvent(v8::AsyncTaskEvent,
+                    Handle<JSObject>::cast(event_data),
+                    true);
+}
+
+
 void Debug::ProcessDebugEvent(v8::DebugEvent event,
                               Handle<JSObject> event_data,
                               bool auto_continue) {

src/debug.h

@@ -366,6 +366,7 @@ class Debug {
   void OnBeforeCompile(Handle<Script> script);
   void OnAfterCompile(Handle<Script> script);
   void OnPromiseEvent(Handle<JSObject> data);
+  void OnAsyncTaskEvent(Handle<JSObject> data);
 
   // API facing.
   void SetEventListener(Handle<Object> callback, Handle<Object> data);
@@ -538,6 +539,8 @@ class Debug {
       Handle<Script> script, v8::DebugEvent type);
   MUST_USE_RESULT MaybeHandle<Object> MakePromiseEvent(
       Handle<JSObject> promise_event);
+  MUST_USE_RESULT MaybeHandle<Object> MakeAsyncTaskEvent(
+      Handle<JSObject> task_event);
 
   // Mirror cache handling.
   void ClearMirrorCache();

src/object-observe.js

@@ -45,6 +45,7 @@ function GetObservationStateJS() {
     observationState.notifierObjectInfoMap = %ObservationWeakMapCreate();
     observationState.pendingObservers = null;
     observationState.nextCallbackPriority = 0;
+    observationState.lastMicrotaskId = 0;
   }
 
   return observationState;
@@ -421,8 +422,19 @@ function ObserverEnqueueIfActive(observer, objectInfo, changeRecord) {
   var callbackInfo = CallbackInfoNormalize(callback);
   if (IS_NULL(GetPendingObservers())) {
     SetPendingObservers(nullProtoObject());
+    if (DEBUG_IS_ACTIVE) {
+      var id = ++GetObservationStateJS().lastMicrotaskId;
+      var name = "Object.observe";
+      %EnqueueMicrotask(function() {
+        %DebugAsyncTaskEvent({ type: "willHandle", id: id, name: name });
+        ObserveMicrotaskRunner();
+        %DebugAsyncTaskEvent({ type: "didHandle", id: id, name: name });
+      });
+      %DebugAsyncTaskEvent({ type: "enqueue", id: id, name: name });
+    } else {
       %EnqueueMicrotask(ObserveMicrotaskRunner);
     }
+  }
   GetPendingObservers()[callbackInfo.priority] = callback;
   callbackInfo.push(changeRecord);
 }

src/promise.js

@@ -29,6 +29,7 @@ var promiseValue = GLOBAL_PRIVATE("Promise#value");
 var promiseOnResolve = GLOBAL_PRIVATE("Promise#onResolve");
 var promiseOnReject = GLOBAL_PRIVATE("Promise#onReject");
 var promiseRaw = GLOBAL_PRIVATE("Promise#raw");
+var lastMicrotaskId = 0;
 
 (function() {
 
@@ -71,7 +72,7 @@ var promiseRaw = GLOBAL_PRIVATE("Promise#raw");
 
   function PromiseDone(promise, status, value, promiseQueue) {
     if (GET_PRIVATE(promise, promiseStatus) === 0) {
-      PromiseEnqueue(value, GET_PRIVATE(promise, promiseQueue));
+      PromiseEnqueue(value, GET_PRIVATE(promise, promiseQueue), status);
       PromiseSet(promise, status, value);
     }
   }
@@ -123,12 +124,24 @@ var promiseRaw = GLOBAL_PRIVATE("Promise#raw");
     }
   }
 
-  function PromiseEnqueue(value, tasks) {
+  function PromiseEnqueue(value, tasks, status) {
+    var id, name, instrumenting = DEBUG_IS_ACTIVE;
     %EnqueueMicrotask(function() {
+      if (instrumenting) {
+        %DebugAsyncTaskEvent({ type: "willHandle", id: id, name: name });
+      }
       for (var i = 0; i < tasks.length; i += 2) {
         PromiseHandle(value, tasks[i], tasks[i + 1])
       }
+      if (instrumenting) {
+        %DebugAsyncTaskEvent({ type: "didHandle", id: id, name: name });
+      }
     });
+    if (instrumenting) {
+      id = ++lastMicrotaskId;
+      name = status > 0 ? "Promise.Resolved" : "Promise.Rejected";
+      %DebugAsyncTaskEvent({ type: "enqueue", id: id, name: name });
+    }
   }
 
   function PromiseIdResolveHandler(x) { return x }
@@ -211,10 +224,14 @@ var promiseRaw = GLOBAL_PRIVATE("Promise#raw");
         GET_PRIVATE(this, promiseOnReject).push(onReject, deferred);
         break;
       case +1:  // Resolved
-        PromiseEnqueue(GET_PRIVATE(this, promiseValue), [onResolve, deferred]);
+        PromiseEnqueue(GET_PRIVATE(this, promiseValue),
+                       [onResolve, deferred],
+                       +1);
         break;
       case -1:  // Rejected
-        PromiseEnqueue(GET_PRIVATE(this, promiseValue), [onReject, deferred]);
+        PromiseEnqueue(GET_PRIVATE(this, promiseValue),
+                       [onReject, deferred],
+                       -1);
         break;
     }
     return deferred.promise;

src/runtime.cc

@@ -5576,6 +5576,15 @@ RUNTIME_FUNCTION(Runtime_DebugPromiseEvent) {
 }
 
 
+RUNTIME_FUNCTION(Runtime_DebugAsyncTaskEvent) {
+  ASSERT(args.length() == 1);
+  HandleScope scope(isolate);
+  CONVERT_ARG_HANDLE_CHECKED(JSObject, data, 0);
+  isolate->debug()->OnAsyncTaskEvent(data);
+  return isolate->heap()->undefined_value();
+}
+
+
 RUNTIME_FUNCTION(Runtime_DeleteProperty) {
   HandleScope scope(isolate);
   ASSERT(args.length() == 3);

src/runtime.h

@@ -78,6 +78,7 @@ namespace internal {
   F(DebugPromiseHandlePrologue, 1, 1) \
   F(DebugPromiseHandleEpilogue, 0, 1) \
   F(DebugPromiseEvent, 1, 1) \
+  F(DebugAsyncTaskEvent, 1, 1) \
   F(FlattenString, 1, 1) \
   F(LoadMutableDouble, 2, 1) \
   F(TryMigrateInstance, 1, 1) \

test/mjsunit/es6/debug-promises-async-task-event.js

+// Copyright 2014 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.
+
+// Flags: --expose-debug-as debug
+
+Debug = debug.Debug;
+
+var base_id = -1;
+var exception = null;
+var expected = [
+  "enqueue #1",
+  "willHandle #1",
+  "then #1",
+  "enqueue #2",
+  "didHandle #1",
+  "willHandle #2",
+  "then #2",
+  "enqueue #3",
+  "didHandle #2",
+  "willHandle #3",
+  "didHandle #3"
+];
+
+function assertLog(msg) {
+  print(msg);
+  assertTrue(expected.length > 0);
+  assertEquals(expected.shift(), msg);
+  if (!expected.length) {
+    Debug.setListener(null);
+  }
+}
+
+function listener(event, exec_state, event_data, data) {
+  if (event != Debug.DebugEvent.AsyncTaskEvent) return;
+  try {
+    if (base_id < 0)
+      base_id = event_data.id();
+    var id = event_data.id() - base_id + 1;
+    assertEquals("Promise.Resolved", event_data.name());
+    assertLog(event_data.type() + " #" + id);
+  } catch (e) {
+    print(e + e.stack)
+    exception = e;
+  }
+}
+
+Debug.setListener(listener);
+
+var resolver;
+var p = new Promise(function(resolve, reject) {
+  resolver = resolve;
+});
+p.then(function() {
+  assertLog("then #1");
+}).then(function() {
+  assertLog("then #2");
+});
+resolver();
+
+assertNull(exception);

test/mjsunit/es6/debug-promises-caught-all.js

@@ -30,6 +30,7 @@ q.catch(
   });
 
 function listener(event, exec_state, event_data, data) {
+  if (event == Debug.DebugEvent.AsyncTaskEvent) return;
   try {
     // Ignore exceptions during startup in stress runs.
     if (step >= 1) return;

test/mjsunit/es6/debug-promises-uncaught-all.js

@@ -26,6 +26,7 @@ var q = p.chain(
   });
 
 function listener(event, exec_state, event_data, data) {
+  if (event == Debug.DebugEvent.AsyncTaskEvent) return;
   try {
     // Ignore exceptions during startup in stress runs.
     if (step >= 1) return;

test/mjsunit/es6/debug-promises-uncaught-uncaught.js

@@ -25,6 +25,7 @@ var q = p.chain(
   });
 
 function listener(event, exec_state, event_data, data) {
+  if (event == Debug.DebugEvent.AsyncTaskEvent) return;
   try {
     // Ignore exceptions during startup in stress runs.
     if (step >= 1) return;

test/mjsunit/es7/object-observe-debug-event.js

+// Copyright 2014 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.
+
+// Flags: --expose-debug-as debug
+
+Debug = debug.Debug;
+
+var base_id = -1;
+var exception = null;
+var expected = [
+  "enqueue #1",
+  "willHandle #1",
+  "didHandle #1",
+];
+
+function assertLog(msg) {
+  print(msg);
+  assertTrue(expected.length > 0);
+  assertEquals(expected.shift(), msg);
+  if (!expected.length) {
+    Debug.setListener(null);
+  }
+}
+
+function listener(event, exec_state, event_data, data) {
+  if (event != Debug.DebugEvent.AsyncTaskEvent) return;
+  try {
+    if (base_id < 0)
+      base_id = event_data.id();
+    var id = event_data.id() - base_id + 1;
+    assertEquals("Object.observe", event_data.name());
+    assertLog(event_data.type() + " #" + id);
+  } catch (e) {
+    print(e + e.stack)
+    exception = e;
+  }
+}
+
+Debug.setListener(listener);
+
+var obj = {};
+Object.observe(obj, function(changes) {
+  print(change.type + " " + change.name + " " + change.oldValue);
+});
+
+obj.foo = 1;
+obj.zoo = 2;
+obj.foo = 3;
+
+assertNull(exception);

test/mjsunit/runtime-gen/debugasynctaskevent.js

+// Copyright 2014 the V8 project authors. All rights reserved.
+// AUTO-GENERATED BY tools/generate-runtime-tests.py, DO NOT MODIFY
+// Flags: --allow-natives-syntax --harmony
+var _data = new Object();
+%DebugAsyncTaskEvent(_data);

tools/generate-runtime-tests.py

@@ -47,11 +47,11 @@ EXPAND_MACROS = [
 # that the parser doesn't bit-rot. Change the values as needed when you add,
 # remove or change runtime functions, but make sure we don't lose our ability
 # to parse them!
-EXPECTED_FUNCTION_COUNT = 416
-EXPECTED_FUZZABLE_COUNT = 331
+EXPECTED_FUNCTION_COUNT = 417
+EXPECTED_FUZZABLE_COUNT = 332
 EXPECTED_CCTEST_COUNT = 6
 EXPECTED_UNKNOWN_COUNT = 4
-EXPECTED_BUILTINS_COUNT = 808
+EXPECTED_BUILTINS_COUNT = 810
 
 
 # Don't call these at all.