[promisehook] Store promise in PromiseReactionJob

src/builtins/builtins-promise.cc

 // Copyright 2016 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/builtins/builtins-utils.h"
 #include "src/builtins/builtins.h"
 #include "src/code-factory.h"
 #include "src/code-stub-assembler.h"
 #include "src/promise-utils.h"
 
@@ skipping 482 matching lines @@
 
     a->Bind(&fulfilled_check);
     {
       Label reject(a);
       Node* const result =
           a->LoadObjectField(promise, JSPromise::kResultOffset);
       a->GotoUnless(a->WordEqual(status, a->SmiConstant(kPromiseFulfilled)),
                     &reject);
 
       // TODO(gsathya): Move this to TF.
-      a->CallRuntime(Runtime::kEnqueuePromiseReactionJob, context, result,
-                     var_on_resolve.value(), deferred,
+      a->CallRuntime(Runtime::kEnqueuePromiseReactionJob, context, promise,

[kozy, 2016/12/15 16:07:58]

Does it mean that before promise can be collected when microtask is already
scheduled but not executed yet and now it's not a true?

var resolve;
var p = new Promise(resolveCb => resolve = resolveCb);
p.then(foo);
p = null;
resolve(); <- promise can be collected after this function call.

function foo() {
} <- now, promise will be collected after this function finished.

+                     result, var_on_resolve.value(), deferred,
                      a->SmiConstant(kPromiseFulfilled));
       a->Goto(&out);
 
       a->Bind(&reject);
       {
         Node* const has_handler = PromiseHasHandler(a, promise);
         Label enqueue(a);
 
         // TODO(gsathya): Fold these runtime calls and move to TF.
         a->GotoIf(has_handler, &enqueue);
         a->CallRuntime(Runtime::kPromiseRevokeReject, context, promise);
         a->Goto(&enqueue);
 
         a->Bind(&enqueue);
         {
-          a->CallRuntime(Runtime::kEnqueuePromiseReactionJob, context, result,
-                         var_on_reject.value(), deferred,
+          a->CallRuntime(Runtime::kEnqueuePromiseReactionJob, context, promise,
+                         result, var_on_reject.value(), deferred,
                          a->SmiConstant(kPromiseRejected));
 
           a->Goto(&out);
         }
       }
     }
   }
 
   a->Bind(&out);
   PromiseSetHasHandler(a, promise);
@@ skipping 370 matching lines @@
     a.Return(a.UndefinedConstant());
   }
 }
 
 void Builtins::Generate_PromiseHandle(compiler::CodeAssemblerState* state) {
   CodeStubAssembler a(state);
   typedef compiler::Node Node;
   typedef CodeStubAssembler::Label Label;
   typedef CodeStubAssembler::Variable Variable;
 
-  Node* const value = a.Parameter(1);
-  Node* const handler = a.Parameter(2);
-  Node* const deferred = a.Parameter(3);
-  Node* const context = a.Parameter(6);
+  Node* const value = a.Parameter(2);
+  Node* const handler = a.Parameter(3);
+  Node* const deferred = a.Parameter(4);
+  Node* const context = a.Parameter(7);
   Isolate* isolate = a.isolate();
 
   // Get promise from deferred
   // TODO(gsathya): Remove this lookup by getting rid of the deferred object.
   Callable getproperty_callable = CodeFactory::GetProperty(isolate);
   Node* const key = a.HeapConstant(isolate->factory()->promise_string());
-  Node* const promise =
+  Node* const deferred_promise =
       a.CallStub(getproperty_callable, context, deferred, key);
 
   Variable var_reason(&a, MachineRepresentation::kTagged);
 
   Node* const is_debug_active = a.IsDebugActive();
   Label run_handler(&a), if_rejectpromise(&a), debug_push(&a, Label::kDeferred),
       debug_pop(&a, Label::kDeferred);
   a.Branch(is_debug_active, &debug_push, &run_handler);
 
   a.Bind(&debug_push);
   {
-    a.CallRuntime(Runtime::kDebugPushPromise, context, promise);
+    a.CallRuntime(Runtime::kDebugPushPromise, context, deferred_promise);
     a.Goto(&run_handler);
   }
 
   a.Bind(&run_handler);
   {
     Callable call_callable = CodeFactory::Call(isolate);
 
     Node* const result =
         a.CallJS(call_callable, context, handler, a.UndefinedConstant(), value);
 
     a.GotoIfException(result, &if_rejectpromise, &var_reason);
 
     // TODO(gsathya): Remove this lookup by getting rid of the deferred object.
     Node* const key = a.HeapConstant(isolate->factory()->resolve_string());
     Node* const on_resolve =
         a.CallStub(getproperty_callable, context, deferred, key);
 
     Label if_internalhandler(&a), if_customhandler(&a, Label::kDeferred);
     a.Branch(a.IsUndefined(on_resolve), &if_internalhandler, &if_customhandler);
 
     a.Bind(&if_internalhandler);
-    InternalResolvePromise(&a, context, promise, result, &debug_pop);
+    InternalResolvePromise(&a, context, deferred_promise, result, &debug_pop);
 
     a.Bind(&if_customhandler);
     {
       Node* const maybe_exception = a.CallJS(call_callable, context, on_resolve,
                                              a.UndefinedConstant(), result);
       a.GotoIfException(maybe_exception, &if_rejectpromise, &var_reason);
       a.Goto(&debug_pop);
     }
   }
 
   a.Bind(&if_rejectpromise);
   {
     // TODO(gsathya): Remove this lookup by getting rid of the deferred object.
     Node* const key = a.HeapConstant(isolate->factory()->reject_string());
     Node* const on_reject =
         a.CallStub(getproperty_callable, context, deferred, key);
 
     Callable promise_handle_reject = CodeFactory::PromiseHandleReject(isolate);
-    a.CallStub(promise_handle_reject, context, promise, on_reject,
+    a.CallStub(promise_handle_reject, context, deferred_promise, on_reject,
                var_reason.value());
     a.Goto(&debug_pop);
   }
 
   a.Bind(&debug_pop);
   {
     Label out(&a);
 
     a.GotoUnless(is_debug_active, &out);
     a.CallRuntime(Runtime::kDebugPopPromise, context);
     a.Goto(&out);
 
     a.Bind(&out);
     a.Return(a.UndefinedConstant());
   }
 }
 
 }  // namespace internal
 }  // namespace v8