[Interpreter] Avoid dereferencing handles in ConstantPoolArrayBuilder.

src/interpreter/constant-array-builder.h

 // Copyright 2015 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.
 
 #ifndef V8_INTERPRETER_CONSTANT_ARRAY_BUILDER_H_
 #define V8_INTERPRETER_CONSTANT_ARRAY_BUILDER_H_
 
 #include "src/identity-map.h"
 #include "src/interpreter/bytecodes.h"
 #include "src/zone-containers.h"
@@ skipping 63 matching lines @@
   index_t AllocateIndex(Handle<Object> object);
 
   struct ConstantArraySlice final : public ZoneObject {
     ConstantArraySlice(Zone* zone, size_t start_index, size_t capacity,
                        OperandSize operand_size);
     void Reserve();
     void Unreserve();
     size_t Allocate(Handle<Object> object);
     Handle<Object> At(size_t index) const;
     void InsertAt(size_t index, Handle<Object> object);
+    bool AllElementsAreUnique() const;
 
     inline size_t available() const { return capacity() - reserved() - size(); }
     inline size_t reserved() const { return reserved_; }
     inline size_t capacity() const { return capacity_; }
     inline size_t size() const { return constants_.size(); }
     inline size_t start_index() const { return start_index_; }
     inline size_t max_index() const { return start_index_ + capacity() - 1; }
     inline OperandSize operand_size() const { return operand_size_; }
 
    private:
     const size_t start_index_;
     const size_t capacity_;
     size_t reserved_;
     OperandSize operand_size_;
     ZoneVector<Handle<Object>> constants_;
 
     DISALLOW_COPY_AND_ASSIGN(ConstantArraySlice);
   };
 
   ConstantArraySlice* IndexToSlice(size_t index) const;
   ConstantArraySlice* OperandSizeToSlice(OperandSize operand_size) const;
 
-  IdentityMap<index_t>* constants_map() { return &constants_map_; }
-
   Isolate* isolate_;
   ConstantArraySlice* idx_slice_[3];
-  IdentityMap<index_t> constants_map_;
+  ZoneMap<Address, index_t> constants_map_;
 };
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_INTERPRETER_CONSTANT_ARRAY_BUILDER_H_