[promises] remove PromiseEnqueue

Removes PromiseEnqueue and moves debugging code to a separate
function which gets called when the debugger is active.

BUG=v8:5343

Review-Url: https://codereview.chromium.org/2450763002
Cr-Commit-Position: refs/heads/master@{#40562}

src/contexts.h

@@ -95,6 +95,7 @@ enum ContextLookupFlags {
   V(PROMISE_HANDLE_INDEX, JSFunction, promise_handle)                     \
   V(PROMISE_HAS_USER_DEFINED_REJECT_HANDLER_INDEX, JSFunction,            \
     promise_has_user_defined_reject_handler)                              \
+  V(PROMISE_DEBUG_GET_INFO_INDEX, JSFunction, promise_debug_get_info)     \
   V(PROMISE_REJECT_INDEX, JSFunction, promise_reject)                     \
   V(PROMISE_RESOLVE_INDEX, JSFunction, promise_resolve)                   \
   V(PROMISE_THEN_INDEX, JSFunction, promise_then)                         \

src/js/promise.js

@@ -146,7 +146,7 @@ function FulfillPromise(promise, status, value, promiseQueue) {
   var tasks = GET_PRIVATE(promise, promiseQueue);
   if (!IS_UNDEFINED(tasks)) {
     var deferred = GET_PRIVATE(promise, promiseDeferredReactionSymbol);
-    PromiseEnqueue(value, tasks, deferred, status);
+    %EnqueuePromiseReactionJob(value, tasks, deferred, status);
   }
   PromiseSet(promise, status, value);
 }
@@ -176,7 +176,7 @@ function PromiseHandle(value, handler, deferred) {
   }
 }
 
-function PromiseEnqueue(value, tasks, deferreds, status) {
+function PromiseDebugGetInfo(deferreds, status) {
   var id, name, instrumenting = DEBUG_IS_ACTIVE;
 
   if (instrumenting) {
@@ -199,7 +199,7 @@ function PromiseEnqueue(value, tasks, deferreds, status) {
       %DebugAsyncTaskEvent("enqueue", id, name);
     }
   }
-  %EnqueuePromiseReactionJob(value, tasks, deferreds, id, name);
+  return [id, name];
 }
 
 function PromiseAttachCallbacks(promise, deferred, onResolve, onReject) {
@@ -388,8 +388,8 @@ function PerformPromiseThen(promise, onResolve, onReject, resultCapability) {
       PromiseAttachCallbacks(promise, resultCapability, onResolve, onReject);
       break;
     case kFulfilled:
-      PromiseEnqueue(GET_PRIVATE(promise, promiseResultSymbol),
-                     onResolve, resultCapability, kFulfilled);
+      %EnqueuePromiseReactionJob(GET_PRIVATE(promise, promiseResultSymbol),
+                                 onResolve, resultCapability, kFulfilled);
       break;
     case kRejected:
       if (!HAS_DEFINED_PRIVATE(promise, promiseHasHandlerSymbol)) {
@@ -397,8 +397,8 @@ function PerformPromiseThen(promise, onResolve, onReject, resultCapability) {
         // Revoke previously triggered reject event.
         %PromiseRevokeReject(promise);
       }
-      PromiseEnqueue(GET_PRIVATE(promise, promiseResultSymbol),
-                     onReject, resultCapability, kRejected);
+      %EnqueuePromiseReactionJob(GET_PRIVATE(promise, promiseResultSymbol),
+                                 onReject, resultCapability, kRejected);
       break;
   }
 
@@ -657,7 +657,8 @@ utils.InstallFunctions(GlobalPromise.prototype, DONT_ENUM, [
   "promise_reject", DoRejectPromise,
   "promise_resolve", ResolvePromise,
   "promise_then", PromiseThen,
-  "promise_handle", PromiseHandle
+  "promise_handle", PromiseHandle,
+  "promise_debug_get_info", PromiseDebugGetInfo
 ]);
 
 // This allows extras to create promises quickly without building extra

src/runtime/runtime-internal.cc

@@ -11,6 +11,7 @@
 #include "src/bootstrapper.h"
 #include "src/conversions.h"
 #include "src/debug/debug.h"
+#include "src/elements.h"
 #include "src/frames-inl.h"
 #include "src/isolate-inl.h"
 #include "src/messages.h"
@@ -573,12 +574,29 @@ RUNTIME_FUNCTION(Runtime_GetAndResetRuntimeCallStats) {
 
 RUNTIME_FUNCTION(Runtime_EnqueuePromiseReactionJob) {
   HandleScope scope(isolate);
-  DCHECK(args.length() == 5);
+  DCHECK(args.length() == 4);
   CONVERT_ARG_HANDLE_CHECKED(Object, value, 0);
   CONVERT_ARG_HANDLE_CHECKED(Object, tasks, 1);
   CONVERT_ARG_HANDLE_CHECKED(Object, deferred, 2);
-  CONVERT_ARG_HANDLE_CHECKED(Object, debug_id, 3);
-  CONVERT_ARG_HANDLE_CHECKED(Object, debug_name, 4);
+  CONVERT_ARG_HANDLE_CHECKED(Object, status, 3);
+  Handle<Object> debug_id = isolate->factory()->undefined_value();
+  Handle<Object> debug_name = isolate->factory()->undefined_value();
+  if (isolate->debug()->is_active()) {
+    Handle<Object> argv[] = {deferred, status};
+    MaybeHandle<Object> maybe_result = Execution::TryCall(
+        isolate, isolate->promise_debug_get_info(),
+        isolate->factory()->undefined_value(), arraysize(argv), argv);
+    Handle<Object> result;
+    if ((maybe_result).ToHandle(&result)) {
+      CHECK(result->IsJSArray());
+      Handle<JSArray> array = Handle<JSArray>::cast(result);
+      ElementsAccessor* accessor = array->GetElementsAccessor();
+      DCHECK(accessor->HasElement(array, 0));
+      DCHECK(accessor->HasElement(array, 1));
+      debug_id = accessor->Get(array, 0);
+      debug_name = accessor->Get(array, 1);
+    }
+  }
   Handle<PromiseReactionJobInfo> info =
       isolate->factory()->NewPromiseReactionJobInfo(value, tasks, deferred,
                                                     debug_id, debug_name,

src/runtime/runtime.h

@@ -290,7 +290,7 @@ namespace internal {
   F(CheckIsBootstrapping, 0, 1)                     \
   F(CreateListFromArrayLike, 1, 1)                  \
   F(EnqueueMicrotask, 1, 1)                         \
-  F(EnqueuePromiseReactionJob, 5, 1)                \
+  F(EnqueuePromiseReactionJob, 4, 1)                \
   F(EnqueuePromiseResolveThenableJob, 4, 1)         \
   F(GetAndResetRuntimeCallStats, -1 /* <= 2 */, 1)  \
   F(ExportExperimentalFromRuntime, 1, 1)            \