[ic] Avoid feedback metadata names table reallocations.

src/type-feedback-vector.cc

 // Copyright 2014 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/type-feedback-vector.h"
 
 #include "src/code-stubs.h"
 #include "src/ic/ic.h"
 #include "src/ic/ic-state.h"
 #include "src/objects.h"
@@ skipping 84 matching lines @@
   }
 
   Handle<TypeFeedbackMetadata> metadata =
       Handle<TypeFeedbackMetadata>::cast(array);
 
   // Add names to NamesTable.
   const int name_count = spec->name_count();
 
   Handle<UnseededNumberDictionary> names;
   if (name_count) {
-    names = UnseededNumberDictionary::New(
-        isolate, base::bits::RoundUpToPowerOfTwo32(name_count), TENURED,
-        USE_CUSTOM_MINIMUM_CAPACITY);
+    names = UnseededNumberDictionary::New(isolate, name_count, TENURED);
   }
 
   int name_index = 0;
   for (int i = 0; i < slot_count; i++) {
     FeedbackVectorSlotKind kind = spec->GetKind(i);
     metadata->SetKind(FeedbackVectorSlot(i), kind);
     if (SlotRequiresName(kind)) {
       Handle<String> name = spec->GetName(name_index);
       DCHECK(!name.is_null());
-      names = UnseededNumberDictionary::AtNumberPut(names, i, name);
+      Handle<UnseededNumberDictionary> new_names =
+          UnseededNumberDictionary::AtNumberPut(names, i, name);
+      DCHECK_EQ(*new_names, *names);
+      names = new_names;
       name_index++;
     }
   }
   DCHECK_EQ(name_count, name_index);
   metadata->set(kNamesTableIndex,
                 name_count ? static_cast<Object*>(*names) : Smi::FromInt(0));
 
   // It's important that the TypeFeedbackMetadata have a COW map, since it's
   // pointed to by both a SharedFunctionInfo and indirectly by closures through
   // the TypeFeedbackVector. The serializer uses the COW map type to decide
@@ skipping 951 matching lines @@
   return BinaryOperationHintFromFeedback(feedback);
 }
 
 CompareOperationHint CompareICNexus::GetCompareOperationFeedback() const {
   int feedback = Smi::cast(GetFeedback())->value();
   return CompareOperationHintFromFeedback(feedback);
 }
 
 }  // namespace internal
 }  // namespace v8