[ic] Use UnseededNumberDictionary as a storage for names in TypeFeedbackMetadata.

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 21 matching lines @@
 
 FeedbackVectorSlotKind TypeFeedbackMetadata::GetKind(
     FeedbackVectorSlot slot) const {
   int index = VectorICComputer::index(kReservedIndexCount, slot.ToInt());
   int data = Smi::cast(get(index))->value();
   return VectorICComputer::decode(data, slot.ToInt());
 }
 
 String* TypeFeedbackMetadata::GetName(FeedbackVectorSlot slot) const {
   DCHECK(SlotRequiresName(GetKind(slot)));
-  FixedArray* names = FixedArray::cast(get(kNamesTableIndex));
-  // TODO(ishell): consider using binary search here or even Dictionary when we
-  // have more ICs with names.
-  Smi* key = Smi::FromInt(slot.ToInt());
-  for (int entry = 0; entry < names->length(); entry += kNameTableEntrySize) {
-    Object* current_key = names->get(entry + kNameTableSlotIndex);
-    if (current_key == key) {
-      Object* name = names->get(entry + kNameTableNameIndex);
-      DCHECK(name->IsString());
-      return String::cast(name);
-    }
-  }
-  UNREACHABLE();
-  return nullptr;
+  UnseededNumberDictionary* names =
+      UnseededNumberDictionary::cast(get(kNamesTableIndex));
+  int entry = names->FindEntry(GetIsolate(), slot.ToInt());
+  CHECK_NE(UnseededNumberDictionary::kNotFound, entry);
+  Object* name = names->ValueAt(entry);
+  DCHECK(name->IsString());
+  return String::cast(name);
 }
 
 void TypeFeedbackMetadata::SetKind(FeedbackVectorSlot slot,
                                    FeedbackVectorSlotKind kind) {
   int index = VectorICComputer::index(kReservedIndexCount, slot.ToInt());
   int data = Smi::cast(get(index))->value();
   int new_data = VectorICComputer::encode(data, slot.ToInt(), kind);
   set(index, Smi::FromInt(new_data));
 }
 
@@ skipping 34 matching lines @@
   for (int i = 0; i < slot_kinds_length; i++) {
     array->set(kReservedIndexCount + i, Smi::FromInt(0));
   }
 
   Handle<TypeFeedbackMetadata> metadata =
       Handle<TypeFeedbackMetadata>::cast(array);
 
   // Add names to NamesTable.
   const int name_count = spec->name_count();
 
-  Handle<FixedArray> names =
-      name_count == 0
-          ? factory->empty_fixed_array()
-          : factory->NewFixedArray(name_count * kNameTableEntrySize);
+  Handle<UnseededNumberDictionary> names =
+      UnseededNumberDictionary::New(isolate, name_count);
+
   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());
-      int entry = name_index * kNameTableEntrySize;
-      names->set(entry + kNameTableSlotIndex, Smi::FromInt(i));
-      names->set(entry + kNameTableNameIndex, *name);
+      names = UnseededNumberDictionary::AtNumberPut(names, i, name);
       name_index++;
     }
   }
   DCHECK_EQ(name_count, name_index);
   metadata->set(kNamesTableIndex, *names);
 
   // 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
   // this object belongs in the startup snapshot and not the partial
@@ skipping 885 matching lines @@
 
 IcCheckType KeyedStoreICNexus::GetKeyType() const {
   Object* feedback = GetFeedback();
   if (feedback == *TypeFeedbackVector::MegamorphicSentinel(GetIsolate())) {
     return static_cast<IcCheckType>(Smi::cast(GetFeedbackExtra())->value());
   }
   return IsPropertyNameFeedback(feedback) ? PROPERTY : ELEMENT;
 }
 }  // namespace internal
 }  // namespace v8