1// Copyright 2016 the V8 project authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "src/lookup-cache.h"
6
7#include "src/objects-inl.h"
8
9namespace v8 {
10namespace internal {
11
12// static
13int DescriptorLookupCache::Hash(Object* source, Name* name) {
14  DCHECK(name->IsUniqueName());
15  // Uses only lower 32 bits if pointers are larger.
16  uint32_t source_hash =
17      static_cast<uint32_t>(reinterpret_cast<uintptr_t>(source)) >>
18      kPointerSizeLog2;
19  uint32_t name_hash = name->hash_field();
20  return (source_hash ^ name_hash) % kLength;
21}
22
23int DescriptorLookupCache::Lookup(Map* source, Name* name) {
24  int index = Hash(source, name);
25  Key& key = keys_[index];
26  if ((key.source == source) && (key.name == name)) return results_[index];
27  return kAbsent;
28}
29
30void DescriptorLookupCache::Update(Map* source, Name* name, int result) {
31  DCHECK(result != kAbsent);
32  int index = Hash(source, name);
33  Key& key = keys_[index];
34  key.source = source;
35  key.name = name;
36  results_[index] = result;
37}
38
39}  // namespace internal
40}  // namespace v8
41