Line data Source code
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 :
9 : namespace v8 {
10 : namespace internal {
11 :
12 : // static
13 : int 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 408068604 : static_cast<uint32_t>(reinterpret_cast<uintptr_t>(source)) >>
18 408068604 : kPointerSizeLog2;
19 : uint32_t name_hash = name->hash_field();
20 408068604 : return (source_hash ^ name_hash) % kLength;
21 : }
22 :
23 299935177 : int DescriptorLookupCache::Lookup(Map* source, Name* name) {
24 : int index = Hash(source, name);
25 299935177 : Key& key = keys_[index];
26 299935177 : if ((key.source == source) && (key.name == name)) return results_[index];
27 : return kAbsent;
28 : }
29 :
30 108133427 : void DescriptorLookupCache::Update(Map* source, Name* name, int result) {
31 : DCHECK(result != kAbsent);
32 : int index = Hash(source, name);
33 108133427 : Key& key = keys_[index];
34 108133427 : key.source = source;
35 108133427 : key.name = name;
36 108133427 : results_[index] = result;
37 108133427 : }
38 :
39 : } // namespace internal
40 : } // namespace v8
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