Use v8 Microtask Queue

V8 now hosts the end-of-microtask work queue. This allows consistent
scheduling of microtask work regardless of where it is implemented (v8 vs blink).

R=adamk@chromium.org

Review URL: https://codereview.chromium.org/167683003

git-svn-id: svn://svn.chromium.org/blink/trunk@169978 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/LayoutTests/inspector/sources/debugger/async-callstack-mutation-observer-expected.txt

@@ -5,6 +5,7 @@ Set timer for test function.
 Captured call stacks in no particular order:
 Call stack:
     0) mutationCallback (async-callstack-mutation-observer.html:21)
+    1) RunMicrotasks ((internal script):(line number))
     [Mutation]
     0) doMutations1 (async-callstack-mutation-observer.html:50)
     1) timeout1 (async-callstack-mutation-observer.html:44)
@@ -13,6 +14,7 @@ Call stack:
 
 Call stack:
     0) mutationCallback (async-callstack-mutation-observer.html:21)
+    1) RunMicrotasks ((internal script):(line number))
     [Mutation]
     0) doMutations2 (async-callstack-mutation-observer.html:64)
     1) timeout2 (async-callstack-mutation-observer.html:57)
@@ -23,9 +25,11 @@ Call stack:
 
 Call stack:
     0) nestedMutationCallback (async-callstack-mutation-observer.html:28)
+    1) RunMicrotasks ((internal script):(line number))
     [Mutation]
     0) doMutations1 (async-callstack-mutation-observer.html:50)
     1) mutationCallback (async-callstack-mutation-observer.html:20)
+    2) RunMicrotasks ((internal script):(line number))
     [Mutation]
     0) doMutations1 (async-callstack-mutation-observer.html:50)
     1) timeout1 (async-callstack-mutation-observer.html:44)
@@ -34,14 +38,17 @@ Call stack:
 
 Call stack:
     0) nestedMutationCallback (async-callstack-mutation-observer.html:28)
+    1) RunMicrotasks ((internal script):(line number))
     [Mutation]
     0) doMutations2 (async-callstack-mutation-observer.html:64)
     1) timeoutFromNestedMutation (async-callstack-mutation-observer.html:76)
     [setTimeout]
     0) nestedMutationCallback (async-callstack-mutation-observer.html:30)
+    1) RunMicrotasks ((internal script):(line number))
     [Mutation]
     0) doMutations1 (async-callstack-mutation-observer.html:50)
     1) mutationCallback (async-callstack-mutation-observer.html:20)
+    2) RunMicrotasks ((internal script):(line number))
     [Mutation]
     0) doMutations1 (async-callstack-mutation-observer.html:50)
     1) timeout1 (async-callstack-mutation-observer.html:44)
@@ -50,6 +57,7 @@ Call stack:
     0) timeoutFromMutation (async-callstack-mutation-observer.html:70)
     [setTimeout]
     0) mutationCallback (async-callstack-mutation-observer.html:23)
+    1) RunMicrotasks ((internal script):(line number))
     [Mutation]
     0) doMutations1 (async-callstack-mutation-observer.html:50)
     1) timeout1 (async-callstack-mutation-observer.html:44)
@@ -60,9 +68,11 @@ Call stack:
     0) timeoutFromNestedMutation (async-callstack-mutation-observer.html:75)
     [setTimeout]
     0) nestedMutationCallback (async-callstack-mutation-observer.html:30)
+    1) RunMicrotasks ((internal script):(line number))
     [Mutation]
     0) doMutations1 (async-callstack-mutation-observer.html:50)
     1) mutationCallback (async-callstack-mutation-observer.html:20)
+    2) RunMicrotasks ((internal script):(line number))
     [Mutation]
     0) doMutations1 (async-callstack-mutation-observer.html:50)
     1) timeout1 (async-callstack-mutation-observer.html:44)

third_party/WebKit/Source/bindings/v8/ScriptRegexp.cpp

@@ -39,7 +39,7 @@ ScriptRegexp::ScriptRegexp(const String& pattern, TextCaseSensitivity caseSensit
 {
     v8::Isolate* isolate = v8::Isolate::GetCurrent();
     v8::HandleScope handleScope(isolate);
-    v8::Context::Scope contextScope(V8PerIsolateData::from(isolate)->ensureRegexContext());
+    v8::Context::Scope contextScope(V8PerIsolateData::from(isolate)->ensureDomInJSContext());
     v8::TryCatch tryCatch;
 
     unsigned flags = v8::RegExp::kNone;
@@ -69,7 +69,7 @@ int ScriptRegexp::match(const String& string, int startFrom, int* matchLength) c
 
     v8::Isolate* isolate = v8::Isolate::GetCurrent();
     v8::HandleScope handleScope(isolate);
-    v8::Context::Scope contextScope(V8PerIsolateData::from(isolate)->ensureRegexContext());
+    v8::Context::Scope contextScope(V8PerIsolateData::from(isolate)->ensureDomInJSContext());
     v8::TryCatch tryCatch;
 
     v8::Local<v8::RegExp> regex = m_regex.newLocal(isolate);

third_party/WebKit/Source/bindings/v8/V8PerIsolateData.cpp

@@ -125,11 +125,11 @@ void V8PerIsolateData::setDOMTemplate(void* domTemplateKey, v8::Handle<v8::Funct
     currentDOMTemplateMap().add(domTemplateKey, UnsafePersistent<v8::FunctionTemplate>(m_isolate, templ));
 }
 
-v8::Local<v8::Context> V8PerIsolateData::ensureRegexContext()
+v8::Local<v8::Context> V8PerIsolateData::ensureDomInJSContext()
 {
-    if (!m_perContextDataForRegex)
-        m_perContextDataForRegex = V8PerContextData::create(v8::Context::New(m_isolate), DOMWrapperWorld::create());
-    return m_perContextDataForRegex->context();
+    if (!m_domInJSPerContextData)
+        m_domInJSPerContextData = V8PerContextData::create(v8::Context::New(m_isolate), DOMWrapperWorld::create());
+    return m_domInJSPerContextData->context();
 }
 
 bool V8PerIsolateData::hasInstance(const WrapperTypeInfo* info, v8::Handle<v8::Value> value)

third_party/WebKit/Source/bindings/v8/V8PerIsolateData.h

@@ -97,7 +97,7 @@ public:
     bool hasInstance(const WrapperTypeInfo*, v8::Handle<v8::Value>);
     v8::Handle<v8::Object> findInstanceInPrototypeChain(const WrapperTypeInfo*, v8::Handle<v8::Value>);
 
-    v8::Local<v8::Context> ensureRegexContext();
+    v8::Local<v8::Context> ensureDomInJSContext();
 
     const char* previousSamplingState() const { return m_previousSamplingState; }
     void setPreviousSamplingState(const char* name) { m_previousSamplingState = name; }
@@ -119,7 +119,7 @@ private:
     OwnPtr<StringCache> m_stringCache;
     OwnPtr<V8HiddenValue> m_hiddenValue;
     ScopedPersistent<v8::Value> m_liveRoot;
-    OwnPtr<V8PerContextData> m_perContextDataForRegex;
+    OwnPtr<V8PerContextData> m_domInJSPerContextData;
 
     const char* m_previousSamplingState;
 

third_party/WebKit/Source/core/dom/Microtask.cpp

@@ -33,39 +33,48 @@
 
 #include "bindings/v8/V8PerIsolateData.h"
 #include "wtf/Vector.h"
+#include <v8.h>
 
 namespace WebCore {
 
-typedef Vector<MicrotaskCallback> MicrotaskQueue;
-
-static MicrotaskQueue& microtaskQueue()
-{
-    DEFINE_STATIC_LOCAL(MicrotaskQueue, microtaskQueue, ());
-    return microtaskQueue;
-}
-
 void Microtask::performCheckpoint()
 {
-    V8PerIsolateData* isolateData = V8PerIsolateData::current();
+    v8::Isolate* isolate = v8::Isolate::GetCurrent();
+    V8PerIsolateData* isolateData = V8PerIsolateData::from(isolate);
     ASSERT(isolateData);
     if (isolateData->recursionLevel() || isolateData->performingMicrotaskCheckpoint())
         return;
     isolateData->setPerformingMicrotaskCheckpoint(true);
 
-    while (!microtaskQueue().isEmpty()) {
-        Vector<MicrotaskCallback> microtasks;
-        microtasks.swap(microtaskQueue());
-        for (size_t i = 0; i < microtasks.size(); ++i) {
-            microtasks[i]();
-        }
-    }
+    v8::HandleScope handleScope(isolate);
+    v8::Local<v8::Context> context = isolateData->ensureDomInJSContext();
+    v8::Context::Scope scope(context);
+    v8::V8::RunMicrotasks(isolate);
 
     isolateData->setPerformingMicrotaskCheckpoint(false);
 }
 
+COMPILE_ASSERT(sizeof(void*) == sizeof(MicrotaskCallback), VoidPtrAndFunctionPtrAreSameSize);
+
+static void microtaskFunctionCallback(const v8::FunctionCallbackInfo<v8::Value>& info)
+{
+    MicrotaskCallback callback =
+        reinterpret_cast<MicrotaskCallback>(reinterpret_cast<intptr_t>(
+            info.Data().As<v8::External>()->Value()));
+    (*callback)();
+}
+
 void Microtask::enqueueMicrotask(MicrotaskCallback callback)
 {
-    microtaskQueue().append(callback);
+    v8::Isolate* isolate = v8::Isolate::GetCurrent();
+    V8PerIsolateData* isolateData = V8PerIsolateData::from(isolate);
+    v8::HandleScope handleScope(isolate);
+    v8::Local<v8::Context> context = isolateData->ensureDomInJSContext();
+    v8::Context::Scope scope(context);
+    v8::Local<v8::External> handler =
+        v8::External::New(isolate,
+            reinterpret_cast<void*>(reinterpret_cast<intptr_t>(callback)));
+    v8::V8::EnqueueMicrotask(isolate, v8::Function::New(isolate, &microtaskFunctionCallback, handler));
 }
 
 } // namespace WebCore

third_party/WebKit/Source/web/WebKit.cpp

@@ -109,6 +109,7 @@ void initialize(Platform* platform)
     v8::V8::SetEntropySource(&generateEntropy);
     v8::V8::SetArrayBufferAllocator(WebCore::v8ArrayBufferAllocator());
     v8::V8::Initialize();
+    v8::V8::SetAutorunMicrotasks(isolate, false);
     WebCore::V8PerIsolateData::ensureInitialized(isolate);
 
     s_isolateInterruptor = new WebCore::V8IsolateInterruptor(v8::Isolate::GetCurrent());