[turbofan] Refactor the lowering of element/property accesses.

src/handles.h

 // Copyright 2011 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_HANDLES_H_
 #define V8_HANDLES_H_
 
 #include "include/v8.h"
 #include "src/base/functional.h"
 #include "src/base/macros.h"
@@ skipping 208 matching lines @@
   V8_INLINE bool ToHandle(Handle<S>* out) const {
     if (location_ == nullptr) {
       *out = Handle<T>::null();
       return false;
     } else {
       *out = Handle<T>(location_);
       return true;
     }
   }
 
+  // Returns the raw address where this handle is stored. This should only be
+  // used for hashing handles; do not ever try to dereference it.
+  V8_INLINE Address address() const { return bit_cast<Address>(location_); }
+
   bool is_null() const { return location_ == nullptr; }
 
  protected:
   T** location_ = nullptr;
 
   // MaybeHandles of different classes are allowed to access each
   // other's location_.
   template <typename>
   friend class MaybeHandle;
 };
@@ skipping 164 matching lines @@
     next = limit = NULL;
     sealed_level = level = 0;
     canonical_scope = NULL;
   }
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HANDLES_H_