VecGeom/base/AlignmentAllocator.h

0001 #ifndef ALIGNMENT_ALLOCATOR_H
0002 #define ALIGNMENT_ALLOCATOR_H
0003
0004 #include <stdlib.h>
0005
0006 // an allocator (for std::vector etc)
0007 // introduced here by Yang Zhang; September 2015 to be used in the Voxel Helper structures (HybridManager etc)
0008
0009 template <typename T, std::size_t N = 16>
0010 class AlignmentAllocator {
0011 public:
0012   typedef T value_type;
0013   typedef std::size_t size_type;
0014   typedef std::ptrdiff_t difference_type;
0015
0016   typedef T *pointer;
0017   typedef const T *const_pointer;
0018
0019   typedef T &reference;
0020   typedef const T &const_reference;
0021
0022 public:
0023   inline AlignmentAllocator() throw() {}
0024
0025   template <typename T2>
0026   inline AlignmentAllocator(const AlignmentAllocator<T2, N> &) throw()
0027   {
0028   }
0029
0030   inline ~AlignmentAllocator() throw() {}
0031
0032   inline pointer adress(reference r) { return &r; }
0033
0034   inline const_pointer adress(const_reference r) const { return &r; }
0035
0036   inline pointer allocate(size_type n) { return (pointer) vecCore::AlignedAlloc(N, n * sizeof(value_type)); }
0037
0038   inline void deallocate(pointer p, size_type) { vecCore::AlignedFree(p); }
0039
0040   inline void construct(pointer p, const value_type &wert) { new (p) value_type(wert); }
0041
0042   inline void destroy(pointer p) { p->~value_type(); }
0043
0044   inline size_type max_size() const throw() { return size_type(-1) / sizeof(value_type); }
0045
0046   template <typename T2>
0047   struct rebind {
0048     typedef AlignmentAllocator<T2, N> other;
0049   };
0050
0051   bool operator!=(const AlignmentAllocator<T, N> &other) const { return !(*this == other); }
0052
0053   // Returns true if and only if storage allocated from *this
0054   // can be deallocated from other, and vice versa.
0055   // Always returns true for stateless allocators.
0056   bool operator==(const AlignmentAllocator<T, N> & /*other*/) const { return true; }
0057 };
0058
0059 #endif