Increment descriptor array slack for prototypes by a constant rather than 50%

src/transitions.cc

 // Copyright 2012 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/v8.h"
 
 #include "src/objects.h"
 #include "src/transitions-inl.h"
 #include "src/utils.h"
 
@@ skipping 88 matching lines @@
         array->SetTarget(index, array->GetTarget(index - 1));
       }
       array->SetKey(index, *name);
       array->SetTarget(index, *target);
       SLOW_DCHECK(array->IsSortedNoDuplicates());
       return;
     }
   }
 
   // We're gonna need a bigger TransitionArray.
-  Handle<TransitionArray> result = Allocate(
-      map->GetIsolate(), new_nof,
-      Map::SlackForArraySize(number_of_transitions, kMaxNumberOfTransitions));
+  Handle<TransitionArray> result =
+      Allocate(map->GetIsolate(), new_nof,
+               Map::SlackForArraySize(false, number_of_transitions,
+                                      kMaxNumberOfTransitions));
 
   // The map's transition array may have shrunk during the allocation above as
   // it was weakly traversed, though it is guaranteed not to disappear. Trim the
   // result copy if needed, and recompute variables.
   DCHECK(IsFullTransitionArray(map->raw_transitions()));
   DisallowHeapAllocation no_gc;
   TransitionArray* array = TransitionArray::cast(map->raw_transitions());
   if (array->number_of_transitions() != number_of_transitions) {
     DCHECK(array->number_of_transitions() < number_of_transitions);
 
@@ skipping 392 matching lines @@
                             PropertyAttributes attributes,
                             int* out_insertion_index) {
   int transition = SearchName(name, out_insertion_index);
   if (transition == kNotFound) {
     return kNotFound;
   }
   return SearchDetails(transition, kind, attributes, out_insertion_index);
 }
 }  // namespace internal
 }  // namespace v8