1// Copyright 2014 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#ifndef V8_COMPILER_NODE_CACHE_H_ 6#define V8_COMPILER_NODE_CACHE_H_ 7 8#include "src/base/functional.h" 9#include "src/base/macros.h" 10 11namespace v8 { 12namespace internal { 13 14// Forward declarations. 15class Zone; 16template <typename> 17class ZoneVector; 18 19 20namespace compiler { 21 22// Forward declarations. 23class Node; 24 25 26// A cache for nodes based on a key. Useful for implementing canonicalization of 27// nodes such as constants, parameters, etc. 28template <typename Key, typename Hash = base::hash<Key>, 29 typename Pred = std::equal_to<Key> > 30class NodeCache final { 31 public: 32 explicit NodeCache(unsigned max = 256) 33 : entries_(nullptr), size_(0), max_(max) {} 34 ~NodeCache() {} 35 36 // Search for node associated with {key} and return a pointer to a memory 37 // location in this cache that stores an entry for the key. If the location 38 // returned by this method contains a non-nullptr node, the caller can use 39 // that 40 // node. Otherwise it is the responsibility of the caller to fill the entry 41 // with a new node. 42 // Note that a previous cache entry may be overwritten if the cache becomes 43 // too full or encounters too many hash collisions. 44 Node** Find(Zone* zone, Key key); 45 46 // Appends all nodes from this cache to {nodes}. 47 void GetCachedNodes(ZoneVector<Node*>* nodes); 48 49 private: 50 struct Entry; 51 52 Entry* entries_; // lazily-allocated hash entries. 53 size_t size_; 54 size_t max_; 55 Hash hash_; 56 Pred pred_; 57 58 bool Resize(Zone* zone); 59 60 DISALLOW_COPY_AND_ASSIGN(NodeCache); 61}; 62 63// Various default cache types. 64typedef NodeCache<int32_t> Int32NodeCache; 65typedef NodeCache<int64_t> Int64NodeCache; 66 67// All we want is the numeric value of the RelocInfo::Mode enum. We typedef 68// below to avoid pulling in assembler.h 69typedef char RelocInfoMode; 70typedef std::pair<int32_t, RelocInfoMode> RelocInt32Key; 71typedef std::pair<int64_t, RelocInfoMode> RelocInt64Key; 72typedef NodeCache<RelocInt32Key> RelocInt32NodeCache; 73typedef NodeCache<RelocInt64Key> RelocInt64NodeCache; 74#if V8_HOST_ARCH_32_BIT 75typedef Int32NodeCache IntPtrNodeCache; 76#else 77typedef Int64NodeCache IntPtrNodeCache; 78#endif 79 80} // namespace compiler 81} // namespace internal 82} // namespace v8 83 84#endif // V8_COMPILER_NODE_CACHE_H_ 85