Create libsampler as V8 sampler library.

src/libsampler/hashmap.h

 // Copyright 2012 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_HASHMAP_H_
-#define V8_HASHMAP_H_
+// This file is ported from src/hashmap.h

[Yang, 2016/05/25 08:29:39]

I wonder whether it makes sense to move src/hashmap.h to src/base, and use that
from both libsampler and v8.

 
-#include "src/allocation.h"
+#ifndef V8_LIBSAMPLER_HASHMAP_H_
+#define V8_LIBSAMPLER_HASHMAP_H_
+
 #include "src/base/bits.h"
 #include "src/base/logging.h"
-#include "src/utils.h"
+#include "src/libsampler/utils.h"
 
 namespace v8 {
-namespace internal {
+namespace sampler {
 
-template<class AllocationPolicy>
-class TemplateHashMapImpl {
+class HashMapImpl {
  public:
   typedef bool (*MatchFun) (void* key1, void* key2);
 
-  // The default capacity.  This is used by the call sites which want
-  // to pass in a non-default AllocationPolicy but want to use the
-  // default value of capacity specified by the implementation.
+  // The default capacity.
   static const uint32_t kDefaultHashMapCapacity = 8;
 
   // initial_capacity is the size of the initial hash map;
   // it must be a power of 2 (and thus must not be 0).
-  TemplateHashMapImpl(MatchFun match,
-                      uint32_t capacity = kDefaultHashMapCapacity,
-                      AllocationPolicy allocator = AllocationPolicy());
+  HashMapImpl(MatchFun match,
+              uint32_t capacity = kDefaultHashMapCapacity);
 
-  ~TemplateHashMapImpl();
+  ~HashMapImpl();
 
   // HashMap entries are (key, value, hash) triplets.
   // Some clients may not need to use the value slot
   // (e.g. implementers of sets, where the key is the value).
   struct Entry {
     void* key;
     void* value;
     uint32_t hash;  // The full hash value for key
     int order;  // If you never remove entries this is the insertion order.
   };
 
   // If an entry with matching key is found, returns that entry.
   // Otherwise, NULL is returned.
   Entry* Lookup(void* key, uint32_t hash) const;
 
   // If an entry with matching key is found, returns that entry.
   // If no matching entry is found, a new entry is inserted with
   // corresponding key, key hash, and NULL value.
-  Entry* LookupOrInsert(void* key, uint32_t hash,
-                        AllocationPolicy allocator = AllocationPolicy());
+  Entry* LookupOrInsert(void* key, uint32_t hash);
 
   // Removes the entry with matching key.
   // It returns the value of the deleted entry
   // or null if there is no value for such key.
   void* Remove(void* key, uint32_t hash);
 
   // Empties the hash map (occupancy() == 0).
   void Clear();
 
   // The number of (non-empty) entries in the table.
@@ skipping 21 matching lines @@
   }
 
  private:
   MatchFun match_;
   Entry* map_;
   uint32_t capacity_;
   uint32_t occupancy_;
 
   Entry* map_end() const { return map_ + capacity_; }
   Entry* Probe(void* key, uint32_t hash) const;
-  void Initialize(uint32_t capacity, AllocationPolicy allocator);
-  void Resize(AllocationPolicy allocator);
+  void Initialize(uint32_t capacity);
+  void Resize();
 };
 
-typedef TemplateHashMapImpl<FreeStoreAllocationPolicy> HashMap;
+typedef HashMapImpl HashMap;
 
-template<class AllocationPolicy>
-TemplateHashMapImpl<AllocationPolicy>::TemplateHashMapImpl(
-    MatchFun match, uint32_t initial_capacity, AllocationPolicy allocator) {
+HashMapImpl::HashMapImpl(MatchFun match, uint32_t initial_capacity) {
   match_ = match;
-  Initialize(initial_capacity, allocator);
+  Initialize(initial_capacity);
 }
 
 
-template<class AllocationPolicy>
-TemplateHashMapImpl<AllocationPolicy>::~TemplateHashMapImpl() {
-  AllocationPolicy::Delete(map_);
+HashMapImpl::~HashMapImpl() {
+  Malloced::Delete(map_);
 }
 
 
-template <class AllocationPolicy>
-typename TemplateHashMapImpl<AllocationPolicy>::Entry*
-TemplateHashMapImpl<AllocationPolicy>::Lookup(void* key, uint32_t hash) const {
+HashMapImpl::Entry* HashMapImpl::Lookup(void* key, uint32_t hash) const {
   Entry* p = Probe(key, hash);
   return p->key != NULL ? p : NULL;
 }
 
 
-template <class AllocationPolicy>
-typename TemplateHashMapImpl<AllocationPolicy>::Entry*
-TemplateHashMapImpl<AllocationPolicy>::LookupOrInsert(
-    void* key, uint32_t hash, AllocationPolicy allocator) {
+HashMapImpl::Entry* HashMapImpl::LookupOrInsert(void* key, uint32_t hash) {
   // Find a matching entry.
   Entry* p = Probe(key, hash);
   if (p->key != NULL) {
     return p;
   }
 
   // No entry found; insert one.
   p->key = key;
   p->value = NULL;
   p->hash = hash;
   p->order = occupancy_;
   occupancy_++;
 
   // Grow the map if we reached >= 80% occupancy.
   if (occupancy_ + occupancy_ / 4 >= capacity_) {
-    Resize(allocator);
+    Resize();
     p = Probe(key, hash);
   }
 
   return p;
 }
 
 
-template<class AllocationPolicy>
-void* TemplateHashMapImpl<AllocationPolicy>::Remove(void* key, uint32_t hash) {
+void* HashMapImpl::Remove(void* key, uint32_t hash) {
   // Lookup the entry for the key to remove.
   Entry* p = Probe(key, hash);
   if (p->key == NULL) {
     // Key not found nothing to remove.
     return NULL;
   }
 
   void* value = p->value;
   // To remove an entry we need to ensure that it does not create an empty
   // entry that will cause the search for another entry to stop too soon. If all
@@ skipping 40 matching lines @@
     }
   }
 
   // Clear the entry which is allowed to en emptied.
   p->key = NULL;
   occupancy_--;
   return value;
 }
 
 
-template<class AllocationPolicy>
-void TemplateHashMapImpl<AllocationPolicy>::Clear() {
+void HashMapImpl::Clear() {
   // Mark all entries as empty.
   const Entry* end = map_end();
   for (Entry* p = map_; p < end; p++) {
     p->key = NULL;
   }
   occupancy_ = 0;
 }
 
 
-template<class AllocationPolicy>
-typename TemplateHashMapImpl<AllocationPolicy>::Entry*
-    TemplateHashMapImpl<AllocationPolicy>::Start() const {
+HashMapImpl::Entry* HashMapImpl::Start() const {
   return Next(map_ - 1);
 }
 
 
-template<class AllocationPolicy>
-typename TemplateHashMapImpl<AllocationPolicy>::Entry*
-    TemplateHashMapImpl<AllocationPolicy>::Next(Entry* p) const {
+HashMapImpl::Entry* HashMapImpl::Next(Entry* p) const {
   const Entry* end = map_end();
   DCHECK(map_ - 1 <= p && p < end);
   for (p++; p < end; p++) {
     if (p->key != NULL) {
       return p;
     }
   }
   return NULL;
 }
 
 
-template <class AllocationPolicy>
-typename TemplateHashMapImpl<AllocationPolicy>::Entry*
-TemplateHashMapImpl<AllocationPolicy>::Probe(void* key, uint32_t hash) const {
+HashMapImpl::Entry* HashMapImpl::Probe(void* key, uint32_t hash) const {
   DCHECK(key != NULL);
 
   DCHECK(base::bits::IsPowerOfTwo32(capacity_));
   Entry* p = map_ + (hash & (capacity_ - 1));
   const Entry* end = map_end();
   DCHECK(map_ <= p && p < end);
 
   DCHECK(occupancy_ < capacity_);  // Guarantees loop termination.
   while (p->key != NULL && (hash != p->hash || !match_(key, p->key))) {
     p++;
     if (p >= end) {
       p = map_;
     }
   }
 
   return p;
 }
 
 
-template<class AllocationPolicy>
-void TemplateHashMapImpl<AllocationPolicy>::Initialize(
-    uint32_t capacity, AllocationPolicy allocator) {
+void HashMapImpl::Initialize(uint32_t capacity) {
   DCHECK(base::bits::IsPowerOfTwo32(capacity));
-  map_ = reinterpret_cast<Entry*>(allocator.New(capacity * sizeof(Entry)));
-  if (map_ == NULL) {
-    v8::internal::FatalProcessOutOfMemory("HashMap::Initialize");
-    return;
-  }
+  map_ = reinterpret_cast<Entry*>(Malloced::New(capacity * sizeof(Entry)));
+  CHECK(map_ != NULL);
   capacity_ = capacity;
   Clear();
 }
 
 
-template<class AllocationPolicy>
-void TemplateHashMapImpl<AllocationPolicy>::Resize(AllocationPolicy allocator) {
+void HashMapImpl::Resize() {
   Entry* map = map_;
   uint32_t n = occupancy_;
 
   // Allocate larger map.
-  Initialize(capacity_ * 2, allocator);
+  Initialize(capacity_ * 2);
 
   // Rehash all current entries.
   for (Entry* p = map; n > 0; p++) {
     if (p->key != NULL) {
-      Entry* entry = LookupOrInsert(p->key, p->hash, allocator);
+      Entry* entry = LookupOrInsert(p->key, p->hash);
       entry->value = p->value;
       entry->order = p->order;
       n--;
     }
   }
 
   // Delete old map.
-  AllocationPolicy::Delete(map);
+  Malloced::Delete(map);
 }
 
-
-// A hash map for pointer keys and values with an STL-like interface.
-template<class Key, class Value, class AllocationPolicy>
-class TemplateHashMap: private TemplateHashMapImpl<AllocationPolicy> {
- public:
-  STATIC_ASSERT(sizeof(Key*) == sizeof(void*));  // NOLINT
-  STATIC_ASSERT(sizeof(Value*) == sizeof(void*));  // NOLINT
-  struct value_type {
-    Key* first;
-    Value* second;
-  };
-
-  class Iterator {
-   public:
-    Iterator& operator++() {
-      entry_ = map_->Next(entry_);
-      return *this;
-    }
-
-    value_type* operator->() { return reinterpret_cast<value_type*>(entry_); }
-    bool operator!=(const Iterator& other) { return  entry_ != other.entry_; }
-
-   private:
-    Iterator(const TemplateHashMapImpl<AllocationPolicy>* map,
-             typename TemplateHashMapImpl<AllocationPolicy>::Entry* entry) :
-        map_(map), entry_(entry) { }
-
-    const TemplateHashMapImpl<AllocationPolicy>* map_;
-    typename TemplateHashMapImpl<AllocationPolicy>::Entry* entry_;
-
-    friend class TemplateHashMap;
-  };
-
-  TemplateHashMap(
-      typename TemplateHashMapImpl<AllocationPolicy>::MatchFun match,
-      AllocationPolicy allocator = AllocationPolicy())
-        : TemplateHashMapImpl<AllocationPolicy>(
-            match,
-            TemplateHashMapImpl<AllocationPolicy>::kDefaultHashMapCapacity,
-            allocator) { }
-
-  Iterator begin() const { return Iterator(this, this->Start()); }
-  Iterator end() const { return Iterator(this, NULL); }
-  Iterator find(Key* key, bool insert = false,
-                AllocationPolicy allocator = AllocationPolicy()) {
-    if (insert) {
-      return Iterator(this, this->LookupOrInsert(key, key->Hash(), allocator));
-    }
-    return Iterator(this, this->Lookup(key, key->Hash()));
-  }
-};
-
-}  // namespace internal
+}  // namespace sampler
 }  // namespace v8
 
-#endif  // V8_HASHMAP_H_
+#endif  // V8_LIBSAMPLER_HASHMAP_H_