Continued fix for 351257. Reusing the feedback vector is too complex.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index f1ab81f3fe3a3e3cce43ab16dc4eb1bed63473c5..492f7528f0d4631558807e6c698dc42e0aca41e8 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -10640,19 +10640,16 @@ void Code::ClearInlineCaches(Code::Kind* kind) {
 }
 
 
-void Code::ClearTypeFeedbackInfo(Heap* heap) {
-  if (kind() != FUNCTION) return;
-  Object* raw_info = type_feedback_info();
-  if (raw_info->IsTypeFeedbackInfo()) {
-    FixedArray* feedback_vector =
-        TypeFeedbackInfo::cast(raw_info)->feedback_vector();
-    for (int i = 0; i < feedback_vector->length(); i++) {
-      Object* obj = feedback_vector->get(i);
-      if (!obj->IsAllocationSite()) {
-        // TODO(mvstanton): Can't I avoid a write barrier for this sentinel?
-        feedback_vector->set(i,
-                             TypeFeedbackInfo::RawUninitializedSentinel(heap));
-      }
+void SharedFunctionInfo::ClearTypeFeedbackInfo(Heap* heap) {
+  FixedArray* vector = feedback_vector();
+  for (int i = 0; i < vector->length(); i++) {
+    Object* obj = vector->get(i);
+    if (!obj->IsAllocationSite()) {
+      // The assert verifies we can skip the write barrier.
+      ASSERT(heap->uninitialized_symbol() ==
+             TypeFeedbackInfo::RawUninitializedSentinel(heap));
+      vector->set(i, TypeFeedbackInfo::RawUninitializedSentinel(heap),
+                  SKIP_WRITE_BARRIER);
     }
   }
 }