Not for landing: Profile Elliott's parsing benchmark

third_party/WebKit/Source/bindings/core/v8/V8GCController.cpp

Index: third_party/WebKit/Source/bindings/core/v8/V8GCController.cpp
diff --git a/third_party/WebKit/Source/bindings/core/v8/V8GCController.cpp b/third_party/WebKit/Source/bindings/core/v8/V8GCController.cpp
index c1f74c4286e808879c9edb1af455d55690c9cafd..6ace7732409d378995db769ac25ac2ec2b4bf627 100644
--- a/third_party/WebKit/Source/bindings/core/v8/V8GCController.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/V8GCController.cpp
@@ -263,6 +263,8 @@ void gcPrologueForMajorGC(v8::Isolate* isolate, bool constructRetainedObjectInfo
 
 } // namespace
 
+double s_time = 0;
+
 void V8GCController::gcPrologue(v8::Isolate* isolate, v8::GCType type, v8::GCCallbackFlags flags)
 {
     if (isMainThread())
@@ -279,6 +281,8 @@ void V8GCController::gcPrologue(v8::Isolate* isolate, v8::GCType type, v8::GCCal
     // a task to schedule the Oilpan's GC.
     // (In practice, there is no finalizer that calls into V8 and thus is safe.)
 
+    s_time = WTF::currentTimeMS();
+
     v8::HandleScope scope(isolate);
     switch (type) {
     case v8::kGCTypeScavenge:
@@ -325,6 +329,28 @@ void UpdateCollectedPhantomHandles(v8::Isolate* isolate)
 void V8GCController::gcEpilogue(v8::Isolate* isolate, v8::GCType type, v8::GCCallbackFlags flags)
 {
     UpdateCollectedPhantomHandles(isolate);
+
+    if (flags & v8::kGCCallbackFlagForced) {
+        fprintf(stderr, "forced ");
+    }
+    switch (type) {
+    case v8::kGCTypeScavenge:
+        fprintf(stderr, "minor ");
+        break;
+    case v8::kGCTypeMarkSweepCompact:
+        fprintf(stderr, "major ");
+        break;
+    case v8::kGCTypeIncrementalMarking:
+        fprintf(stderr, "incremental ");
+        break;
+    case v8::kGCTypeProcessWeakCallbacks:
+        fprintf(stderr, "weak-callback ");
+        break;
+    default:
+        ASSERT_NOT_REACHED();
+    }
+    fprintf(stderr, "V8 GC: %.2lf ms\n", WTF::currentTimeMS() - s_time);
+
     switch (type) {
     case v8::kGCTypeScavenge:
         TRACE_EVENT_END1("devtools.timeline,v8", "MinorGC", "usedHeapSizeAfter", usedHeapSize(isolate));