Tenure allocation sites only when semi-space is maximum size.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index 1fee95b6b9a897615b25bcc36309a0a1206fdf6a..d9303f35ed269621a1f0648f787651b2927a2051 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -13436,6 +13436,19 @@ void AllocationSite::AddDependentCompilationInfo(Handle<AllocationSite> site,
 }
 
 
+const char* AllocationSite::PretenureDecisionName(PretenureDecision decision) {
+  switch (decision) {
+    case kUndecided: return "undecided";
+    case kDontTenure: return "don't tenure";
+    case kMaybeTenure: return "maybe tenure";
+    case kTenure: return "tenure";
+    case kZombie: return "zombie";
+    default: UNREACHABLE();
+  }
+  return NULL;
+}
+
+
 void JSObject::UpdateAllocationSite(Handle<JSObject> object,
                                     ElementsKind to_kind) {
   if (!object->IsJSArray()) return;