xref: /freebsd/contrib/llvm-project/llvm/include/llvm/Support/RecyclingAllocator.h (revision a0409676120c1e558d0ade943019934e0f15118d)
1 //==- llvm/Support/RecyclingAllocator.h - Recycling Allocator ----*- C++ -*-==//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file defines the RecyclingAllocator class.  See the doxygen comment for
10 // RecyclingAllocator for more details on the implementation.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_SUPPORT_RECYCLINGALLOCATOR_H
15 #define LLVM_SUPPORT_RECYCLINGALLOCATOR_H
16 
17 #include "llvm/Support/Recycler.h"
18 
19 namespace llvm {
20 
21 /// RecyclingAllocator - This class wraps an Allocator, adding the
22 /// functionality of recycling deleted objects.
23 ///
24 template <class AllocatorType, class T, size_t Size = sizeof(T),
25           size_t Align = alignof(T)>
26 class RecyclingAllocator {
27 private:
28   /// Base - Implementation details.
29   ///
30   Recycler<T, Size, Align> Base;
31 
32   /// Allocator - The wrapped allocator.
33   ///
34   AllocatorType Allocator;
35 
36 public:
37   ~RecyclingAllocator() { Base.clear(Allocator); }
38 
39   /// Allocate - Return a pointer to storage for an object of type
40   /// SubClass. The storage may be either newly allocated or recycled.
41   ///
42   template<class SubClass>
43   SubClass *Allocate() { return Base.template Allocate<SubClass>(Allocator); }
44 
45   T *Allocate() { return Base.Allocate(Allocator); }
46 
47   /// Deallocate - Release storage for the pointed-to object. The
48   /// storage will be kept track of and may be recycled.
49   ///
50   template<class SubClass>
51   void Deallocate(SubClass* E) { return Base.Deallocate(Allocator, E); }
52 
53   void PrintStats() {
54     Allocator.PrintStats();
55     Base.PrintStats();
56   }
57 };
58 
59 }
60 
61 template<class AllocatorType, class T, size_t Size, size_t Align>
62 inline void *operator new(size_t size,
63                           llvm::RecyclingAllocator<AllocatorType,
64                                                    T, Size, Align> &Allocator) {
65   assert(size <= Size && "allocation size exceeded");
66   return Allocator.Allocate();
67 }
68 
69 template<class AllocatorType, class T, size_t Size, size_t Align>
70 inline void operator delete(void *E,
71                             llvm::RecyclingAllocator<AllocatorType,
72                                                      T, Size, Align> &A) {
73   A.Deallocate(E);
74 }
75 
76 #endif
77