libstdc++
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Bitmap Allocator, primary template.
pointer __gnu_cxx::bitmap_allocator::_M_allocate_single_object | ( | ) | throw (std::bad_alloc) [inline] |
Allocates memory for a single object of size sizeof(_Tp).
std::bad_alloc. | If memory can not be allocated. |
Complexity: Worst case complexity is O(N), but that is hardly ever hit. If and when this particular case is encountered, the next few cases are guaranteed to have a worst case complexity of O(1)! That's why this function performs very well on average. You can consider this function to have a complexity referred to commonly as: Amortized Constant time.
Definition at line 825 of file bitmap_allocator.h.
References __gnu_cxx::_Bit_scan_forward(), __gnu_cxx::__detail::__bit_allocate(), and __gnu_cxx::__detail::__num_bitmaps().
void __gnu_cxx::bitmap_allocator::_M_deallocate_single_object | ( | pointer | __p | ) | throw () [inline] |
Deallocates memory that belongs to a single object of size sizeof(_Tp).
Complexity: O(lg(N)), but the worst case is not hit often! This is because containers usually deallocate memory close to each other and this case is handled in O(1) time by the deallocate function.
Definition at line 915 of file bitmap_allocator.h.
References std::__rotate(), __gnu_cxx::__detail::__bit_free(), __gnu_cxx::__detail::__num_bitmaps(), and __gnu_cxx::free_list::_M_insert().