[collections] Add OrderedHashTable::Delete

Bug: v8:5717
Change-Id: Icc601c409ac79195991facf1cb2027aab6145ff8
Reviewed-on: https://chromium-review.googlesource.com/540659
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46066}

src/objects.cc

@@ -18158,14 +18158,9 @@ Object* OrderedHashTable<Derived, entrysize>::HasKey(Isolate* isolate,
                                                      Object* key) {
   DCHECK(table->IsOrderedHashTable());
   DisallowHeapAllocation no_gc;
-  int entry = table->KeyToFirstEntry(isolate, key);
-  // Walk the chain in the bucket to find the key.
-  while (entry != kNotFound) {
-    Object* candidate_key = table->KeyAt(entry);
-    if (candidate_key->SameValueZero(key)) return isolate->heap()->true_value();
-    entry = table->NextChainEntry(entry);
-  }
-  return isolate->heap()->false_value();
+  int entry = table->FindEntry(isolate, key);
+  return entry == kNotFound ? isolate->heap()->false_value()
+                            : isolate->heap()->true_value();
 }
 
 Handle<OrderedHashSet> OrderedHashSet::Add(Handle<OrderedHashSet> table,
@@ -18267,20 +18262,35 @@ Handle<Derived> OrderedHashTable<Derived, entrysize>::Rehash(
   return new_table;
 }
 
+template <class Derived, int entrysize>
+bool OrderedHashTable<Derived, entrysize>::Delete(Isolate* isolate,
+                                                  Derived* table, Object* key) {
+  DisallowHeapAllocation no_gc;
+  int entry = table->FindEntry(isolate, key);
+  if (entry == kNotFound) return false;
+
+  int nof = table->NumberOfElements();
+  int nod = table->NumberOfDeletedElements();
+  int index = table->EntryToIndex(entry);
+
+  Object* hole = isolate->heap()->the_hole_value();
+  for (int i = 0; i < entrysize; ++i) {
+    table->set(index + i, hole);
+  }
+
+  table->SetNumberOfElements(nof - 1);
+  table->SetNumberOfDeletedElements(nod + 1);
+
+  return true;
+}
+
 Object* OrderedHashMap::Get(Isolate* isolate, OrderedHashMap* table,
                             Object* key) {
   DCHECK(table->IsOrderedHashMap());
   DisallowHeapAllocation no_gc;
-  int entry = table->KeyToFirstEntry(isolate, key);
-  // Walk the chain in the bucket to find the key.
-  while (entry != kNotFound) {
-    Object* candidate_key = table->KeyAt(entry);
-    if (candidate_key->SameValueZero(key)) {
+  int entry = table->FindEntry(isolate, key);
+  if (entry == kNotFound) return isolate->heap()->undefined_value();
   return table->ValueAt(entry);
-    }
-    entry = table->NextChainEntry(entry);
-  }
-  return isolate->heap()->undefined_value();
 }
 
 Handle<OrderedHashMap> OrderedHashMap::Add(Handle<OrderedHashMap> table,
@@ -18332,6 +18342,10 @@ template Handle<OrderedHashSet> OrderedHashTable<OrderedHashSet, 1>::Clear(
 template Object* OrderedHashTable<OrderedHashSet, 1>::HasKey(
     Isolate* isolate, OrderedHashSet* table, Object* key);
 
+template bool OrderedHashTable<OrderedHashSet, 1>::Delete(Isolate* isolate,
+                                                          OrderedHashSet* table,
+                                                          Object* key);
+
 template Handle<OrderedHashMap> OrderedHashTable<OrderedHashMap, 2>::Allocate(
     Isolate* isolate, int capacity, PretenureFlag pretenure);
 
@@ -18347,6 +18361,10 @@ template Handle<OrderedHashMap> OrderedHashTable<OrderedHashMap, 2>::Clear(
 template Object* OrderedHashTable<OrderedHashMap, 2>::HasKey(
     Isolate* isolate, OrderedHashMap* table, Object* key);
 
+template bool OrderedHashTable<OrderedHashMap, 2>::Delete(Isolate* isolate,
+                                                          OrderedHashMap* table,
+                                                          Object* key);
+
 template <>
 Handle<SmallOrderedHashSet>
 SmallOrderedHashTable<SmallOrderedHashSet>::Allocate(Isolate* isolate,

src/objects/hash-table.h

@@ -410,6 +410,10 @@ class OrderedHashTable : public FixedArray {
   // existing iterators can be updated.
   static Handle<Derived> Clear(Handle<Derived> table);
 
+  // Returns a true value if the OrderedHashTable contains the key and
+  // the key has been deleted. This does not shrink the table.
+  static bool Delete(Isolate* isolate, Derived* table, Object* key);
+
   // Returns a true value if the OrderedHashTable contains the key
   static Object* HasKey(Isolate* isolate, Derived* table, Object* key);
 
@@ -457,6 +461,18 @@ class OrderedHashTable : public FixedArray {
     return HashToEntry(Smi::cast(hash)->value());
   }
 
+  int FindEntry(Isolate* isolate, Object* key) {
+    int entry = KeyToFirstEntry(isolate, key);
+    // Walk the chain in the bucket to find the key.
+    while (entry != kNotFound) {
+      Object* candidate_key = KeyAt(entry);
+      if (candidate_key->SameValueZero(key)) break;
+      entry = NextChainEntry(entry);
+    }
+
+    return entry;
+  }
+
   int NextChainEntry(int entry) {
     Object* next_entry = get(EntryToIndex(entry) + kChainOffset);
     return Smi::cast(next_entry)->value();

test/cctest/test-orderedhashtable.cc

@@ -13,6 +13,19 @@ static Isolate* GetIsolateFrom(LocalContext* context) {
   return reinterpret_cast<Isolate*>((*context)->GetIsolate());
 }
 
+void CopyHashCode(Isolate* isolate, Handle<JSReceiver> from,
+                  Handle<JSReceiver> to) {
+  Handle<Name> hash_code_symbol = isolate->factory()->hash_code_symbol();
+  Handle<Smi> hash =
+      Handle<Smi>::cast(JSObject::GetDataProperty(from, hash_code_symbol));
+
+  LookupIterator it(to, hash_code_symbol, to, LookupIterator::OWN);
+  CHECK(to->AddDataProperty(
+              &it, hash, NONE, v8::internal::AccessCheckInfo::THROW_ON_ERROR,
+              v8::internal::AccessCheckInfo::CERTAINLY_NOT_STORE_FROM_KEYED)
+            .IsJust());
+}
+
 void Verify(Handle<SmallOrderedHashSet> set) {
 #if VERIFY_HEAP
   set->ObjectVerify();
@@ -31,6 +44,12 @@ void Verify(Handle<OrderedHashMap> map) {
 #endif
 }
 
+void Verify(Handle<OrderedHashSet> set) {
+#if VERIFY_HEAP
+  set->ObjectVerify();
+#endif
+}
+
 TEST(SmallOrderedHashSetInsertion) {
   LocalContext context;
   Isolate* isolate = GetIsolateFrom(&context);
@@ -211,20 +230,8 @@ TEST(SmallOrderedHashSetDuplicateHashCode) {
   CHECK_EQ(1, set->NumberOfElements());
   CHECK(set->HasKey(isolate, key1));
 
-  Handle<Name> hash_code_symbol = isolate->factory()->hash_code_symbol();
-  Handle<Smi> hash =
-      Handle<Smi>::cast(JSObject::GetDataProperty(key1, hash_code_symbol));
-
   Handle<JSObject> key2 = factory->NewJSObjectWithNullProto();
-  LookupIterator it(key2, hash_code_symbol, key2, LookupIterator::OWN);
-  CHECK(key2->AddDataProperty(
-                &it, hash, NONE, v8::internal::AccessCheckInfo::THROW_ON_ERROR,
-                v8::internal::AccessCheckInfo::CERTAINLY_NOT_STORE_FROM_KEYED)
-            .IsJust());
-  CHECK(!key1->SameValue(*key2));
-  Object* hash1 = key1->GetHash();
-  Object* hash2 = key2->GetHash();
-  CHECK_EQ(hash1, hash2);
+  CopyHashCode(isolate, key1, key2);
 
   set = SmallOrderedHashSet::Add(set, key2);
   Verify(set);
@@ -612,16 +619,8 @@ TEST(OrderedHashMapDuplicateHashCode) {
   CHECK_EQ(1, map->NumberOfElements());
   CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key1));
 
-  Handle<Name> hash_code_symbol = isolate->factory()->hash_code_symbol();
-  Handle<Smi> hash =
-      Handle<Smi>::cast(JSObject::GetDataProperty(key1, hash_code_symbol));
-
   Handle<JSObject> key2 = factory->NewJSObjectWithNullProto();
-  LookupIterator it(key2, hash_code_symbol, key2, LookupIterator::OWN);
-  CHECK(key2->AddDataProperty(
-                &it, hash, NONE, v8::internal::AccessCheckInfo::THROW_ON_ERROR,
-                v8::internal::AccessCheckInfo::CERTAINLY_NOT_STORE_FROM_KEYED)
-            .IsJust());
+  CopyHashCode(isolate, key1, key2);
 
   map = OrderedHashMap::Add(map, key2, value);
   Verify(map);
@@ -630,3 +629,312 @@ TEST(OrderedHashMapDuplicateHashCode) {
   CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key1));
   CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key2));
 }
+
+TEST(OrderedHashMapDeletion) {
+  LocalContext context;
+  Isolate* isolate = GetIsolateFrom(&context);
+  Factory* factory = isolate->factory();
+  HandleScope scope(isolate);
+  Handle<Object> true_val = factory->true_value();
+  Handle<Object> false_val = factory->false_value();
+  Handle<Smi> value1(Smi::FromInt(1), isolate);
+  Handle<String> value = factory->NewStringFromAsciiChecked("bar");
+
+  Handle<OrderedHashMap> map = factory->NewOrderedHashMap();
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(0, map->NumberOfElements());
+  CHECK_EQ(0, map->NumberOfDeletedElements());
+
+  // Delete from an empty hash table
+  Handle<Smi> key1(Smi::FromInt(1), isolate);
+  CHECK(!OrderedHashMap::Delete(isolate, *map, *key1));
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(0, map->NumberOfElements());
+  CHECK_EQ(0, map->NumberOfDeletedElements());
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key1));
+
+  map = OrderedHashMap::Add(map, key1, value1);
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(1, map->NumberOfElements());
+  CHECK_EQ(0, map->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key1));
+
+  // Delete single existing key
+  CHECK(OrderedHashMap::Delete(isolate, *map, *key1));
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(0, map->NumberOfElements());
+  CHECK_EQ(1, map->NumberOfDeletedElements());
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key1));
+
+  map = OrderedHashMap::Add(map, key1, value1);
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(1, map->NumberOfElements());
+  CHECK_EQ(1, map->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key1));
+
+  Handle<String> key2 = factory->NewStringFromAsciiChecked("foo");
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key2));
+  map = OrderedHashMap::Add(map, key2, value);
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(2, map->NumberOfElements());
+  CHECK_EQ(1, map->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key2));
+
+  Handle<Symbol> key3 = factory->NewSymbol();
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key3));
+  map = OrderedHashMap::Add(map, key3, value);
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(3, map->NumberOfElements());
+  CHECK_EQ(1, map->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key1));
+  CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key2));
+  CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key3));
+
+  // Delete multiple existing keys
+  CHECK(OrderedHashMap::Delete(isolate, *map, *key1));
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(2, map->NumberOfElements());
+  CHECK_EQ(2, map->NumberOfDeletedElements());
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key1));
+  CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key2));
+  CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key3));
+
+  CHECK(OrderedHashMap::Delete(isolate, *map, *key2));
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(1, map->NumberOfElements());
+  CHECK_EQ(3, map->NumberOfDeletedElements());
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key1));
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key2));
+  CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key3));
+
+  CHECK(OrderedHashMap::Delete(isolate, *map, *key3));
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(0, map->NumberOfElements());
+  CHECK_EQ(4, map->NumberOfDeletedElements());
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key1));
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key2));
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key3));
+
+  // Delete non existant key from non new hash table
+  CHECK(!OrderedHashMap::Delete(isolate, *map, *key3));
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(0, map->NumberOfElements());
+  CHECK_EQ(4, map->NumberOfDeletedElements());
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key1));
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key2));
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key3));
+
+  // Delete non existant key from non empty hash table
+  map = OrderedHashMap::Shrink(map);
+  map = OrderedHashMap::Add(map, key1, value);
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(1, map->NumberOfElements());
+  CHECK_EQ(0, map->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key1));
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key2));
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key3));
+  CHECK(!OrderedHashMap::Delete(isolate, *map, *key2));
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(1, map->NumberOfElements());
+  CHECK_EQ(0, map->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key1));
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key2));
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key3));
+}
+
+TEST(OrderedHashMapDuplicateHashCodeDeletion) {
+  LocalContext context;
+  Isolate* isolate = GetIsolateFrom(&context);
+  Factory* factory = isolate->factory();
+  HandleScope scope(isolate);
+
+  Handle<OrderedHashMap> map = factory->NewOrderedHashMap();
+  Handle<JSObject> key1 = factory->NewJSObjectWithNullProto();
+  Handle<JSObject> value = factory->NewJSObjectWithNullProto();
+  Handle<Object> true_val = factory->true_value();
+  Handle<Object> false_val = factory->false_value();
+  map = OrderedHashMap::Add(map, key1, value);
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(1, map->NumberOfElements());
+  CHECK_EQ(0, map->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key1));
+
+  Handle<JSObject> key2 = factory->NewJSObjectWithNullProto();
+  CopyHashCode(isolate, key1, key2);
+
+  // We shouldn't be able to delete the key!
+  CHECK(!OrderedHashMap::Delete(isolate, *map, *key2));
+  Verify(map);
+  CHECK_EQ(2, map->NumberOfBuckets());
+  CHECK_EQ(1, map->NumberOfElements());
+  CHECK_EQ(0, map->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashMap::HasKey(isolate, *map, *key1));
+  CHECK_EQ(*false_val, OrderedHashMap::HasKey(isolate, *map, *key2));
+}
+
+TEST(OrderedHashSetDeletion) {
+  LocalContext context;
+  Isolate* isolate = GetIsolateFrom(&context);
+  Factory* factory = isolate->factory();
+  HandleScope scope(isolate);
+  Handle<Object> true_val = factory->true_value();
+  Handle<Object> false_val = factory->false_value();
+
+  Handle<OrderedHashSet> set = factory->NewOrderedHashSet();
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(0, set->NumberOfElements());
+  CHECK_EQ(0, set->NumberOfDeletedElements());
+
+  // Delete from an empty hash table
+  Handle<Smi> key1(Smi::FromInt(1), isolate);
+  CHECK(!OrderedHashSet::Delete(isolate, *set, *key1));
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(0, set->NumberOfElements());
+  CHECK_EQ(0, set->NumberOfDeletedElements());
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key1));
+
+  set = OrderedHashSet::Add(set, key1);
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(1, set->NumberOfElements());
+  CHECK_EQ(0, set->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashSet::HasKey(isolate, *set, *key1));
+
+  // Delete single existing key
+  CHECK(OrderedHashSet::Delete(isolate, *set, *key1));
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(0, set->NumberOfElements());
+  CHECK_EQ(1, set->NumberOfDeletedElements());
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key1));
+
+  set = OrderedHashSet::Add(set, key1);
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(1, set->NumberOfElements());
+  CHECK_EQ(1, set->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashSet::HasKey(isolate, *set, *key1));
+
+  Handle<String> key2 = factory->NewStringFromAsciiChecked("foo");
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key2));
+  set = OrderedHashSet::Add(set, key2);
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(2, set->NumberOfElements());
+  CHECK_EQ(1, set->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashSet::HasKey(isolate, *set, *key2));
+
+  Handle<Symbol> key3 = factory->NewSymbol();
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key3));
+  set = OrderedHashSet::Add(set, key3);
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(3, set->NumberOfElements());
+  CHECK_EQ(1, set->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashSet::HasKey(isolate, *set, *key1));
+  CHECK_EQ(*true_val, OrderedHashSet::HasKey(isolate, *set, *key2));
+  CHECK_EQ(*true_val, OrderedHashSet::HasKey(isolate, *set, *key3));
+
+  // Delete multiple existing keys
+  CHECK(OrderedHashSet::Delete(isolate, *set, *key1));
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(2, set->NumberOfElements());
+  CHECK_EQ(2, set->NumberOfDeletedElements());
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key1));
+  CHECK_EQ(*true_val, OrderedHashSet::HasKey(isolate, *set, *key2));
+  CHECK_EQ(*true_val, OrderedHashSet::HasKey(isolate, *set, *key3));
+
+  CHECK(OrderedHashSet::Delete(isolate, *set, *key2));
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(1, set->NumberOfElements());
+  CHECK_EQ(3, set->NumberOfDeletedElements());
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key1));
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key2));
+  CHECK_EQ(*true_val, OrderedHashSet::HasKey(isolate, *set, *key3));
+
+  CHECK(OrderedHashSet::Delete(isolate, *set, *key3));
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(0, set->NumberOfElements());
+  CHECK_EQ(4, set->NumberOfDeletedElements());
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key1));
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key2));
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key3));
+
+  // Delete non existant key from non new hash table
+  CHECK(!OrderedHashSet::Delete(isolate, *set, *key3));
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(0, set->NumberOfElements());
+  CHECK_EQ(4, set->NumberOfDeletedElements());
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key1));
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key2));
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key3));
+
+  // Delete non existant key from non empty hash table
+  set = OrderedHashSet::Shrink(set);
+  set = OrderedHashSet::Add(set, key1);
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(1, set->NumberOfElements());
+  CHECK_EQ(0, set->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashSet::HasKey(isolate, *set, *key1));
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key2));
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key3));
+  CHECK(!OrderedHashSet::Delete(isolate, *set, *key2));
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(1, set->NumberOfElements());
+  CHECK_EQ(0, set->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashSet::HasKey(isolate, *set, *key1));
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key2));
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key3));
+}
+
+TEST(OrderedHashSetDuplicateHashCodeDeletion) {
+  LocalContext context;
+  Isolate* isolate = GetIsolateFrom(&context);
+  Factory* factory = isolate->factory();
+  HandleScope scope(isolate);
+
+  Handle<OrderedHashSet> set = factory->NewOrderedHashSet();
+  Handle<JSObject> key1 = factory->NewJSObjectWithNullProto();
+  Handle<Object> true_val = factory->true_value();
+  Handle<Object> false_val = factory->false_value();
+  set = OrderedHashSet::Add(set, key1);
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(1, set->NumberOfElements());
+  CHECK_EQ(0, set->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashSet::HasKey(isolate, *set, *key1));
+
+  Handle<JSObject> key2 = factory->NewJSObjectWithNullProto();
+  CopyHashCode(isolate, key1, key2);
+
+  // We shouldn't be able to delete the key!
+  CHECK(!OrderedHashSet::Delete(isolate, *set, *key2));
+  Verify(set);
+  CHECK_EQ(2, set->NumberOfBuckets());
+  CHECK_EQ(1, set->NumberOfElements());
+  CHECK_EQ(0, set->NumberOfDeletedElements());
+  CHECK_EQ(*true_val, OrderedHashSet::HasKey(isolate, *set, *key1));
+  CHECK_EQ(*false_val, OrderedHashSet::HasKey(isolate, *set, *key2));
+}