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_ZONE_ALLOCATOR_H_
6 #define V8_ZONE_ALLOCATOR_H_
7 
8 #include <limits>
9 
10 #include "src/zone.h"
11 
12 namespace v8 {
13 namespace internal {
14 
15 template<typename T>
16 class zone_allocator {
17  public:
18   typedef T* pointer;
19   typedef const T* const_pointer;
20   typedef T& reference;
21   typedef const T& const_reference;
22   typedef T value_type;
23   typedef size_t size_type;
24   typedef ptrdiff_t difference_type;
25   template<class O> struct rebind {
26     typedef zone_allocator<O> other;
27   };
28 
zone_allocator(Zone * zone)29   explicit zone_allocator(Zone* zone) throw() : zone_(zone) {}
zone_allocator(const zone_allocator & other)30   explicit zone_allocator(const zone_allocator& other) throw()
31       : zone_(other.zone_) {}
zone_allocator(const zone_allocator<U> & other)32   template<typename U> zone_allocator(const zone_allocator<U>& other) throw()
33       : zone_(other.zone_) {}
34   template<typename U> friend class zone_allocator;
35 
address(reference x)36   pointer address(reference x) const {return &x;}
address(const_reference x)37   const_pointer address(const_reference x) const {return &x;}
38 
39   pointer allocate(size_type n, const void* hint = 0) {
40     return static_cast<pointer>(zone_->NewArray<value_type>(
41             static_cast<int>(n)));
42   }
deallocate(pointer p,size_type)43   void deallocate(pointer p, size_type) { /* noop for Zones */ }
44 
max_size()45   size_type max_size() const throw() {
46     return std::numeric_limits<int>::max() / sizeof(value_type);
47   }
construct(pointer p,const T & val)48   void construct(pointer p, const T& val) {
49     new(static_cast<void*>(p)) T(val);
50   }
destroy(pointer p)51   void destroy(pointer p) { p->~T(); }
52 
53   bool operator==(zone_allocator const& other) {
54     return zone_ == other.zone_;
55   }
56   bool operator!=(zone_allocator const& other) {
57     return zone_ != other.zone_;
58   }
59 
60  private:
61   zone_allocator();
62   Zone* zone_;
63 };
64 
65 typedef zone_allocator<bool> ZoneBoolAllocator;
66 typedef zone_allocator<int> ZoneIntAllocator;
67 } }  // namespace v8::internal
68 
69 #endif  // V8_ZONE_ALLOCATOR_H_
70