| //===------------------------ memory.cpp ----------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "memory" |
| |
| _LIBCPP_BEGIN_NAMESPACE_STD |
| |
| namespace |
| { |
| |
| template <class T> |
| inline T |
| increment(T& t) |
| { |
| return __sync_add_and_fetch(&t, 1); |
| } |
| |
| template <class T> |
| inline T |
| decrement(T& t) |
| { |
| return __sync_add_and_fetch(&t, -1); |
| } |
| |
| } // namespace |
| |
| |
| const allocator_arg_t allocator_arg = allocator_arg_t(); |
| |
| bad_weak_ptr::~bad_weak_ptr() throw() {} |
| |
| const char* |
| bad_weak_ptr::what() const throw() |
| { |
| return "bad_weak_ptr"; |
| } |
| |
| __shared_count::~__shared_count() |
| { |
| } |
| |
| void |
| __shared_count::__add_shared() |
| { |
| increment(__shared_owners_); |
| } |
| |
| void |
| __shared_count::__release_shared() |
| { |
| if (decrement(__shared_owners_) == -1) |
| __on_zero_shared(); |
| } |
| |
| __shared_weak_count::~__shared_weak_count() |
| { |
| } |
| |
| void |
| __shared_weak_count::__add_shared() |
| { |
| __shared_count::__add_shared(); |
| __add_weak(); |
| } |
| |
| void |
| __shared_weak_count::__add_weak() |
| { |
| increment(__shared_weak_owners_); |
| } |
| |
| void |
| __shared_weak_count::__release_shared() |
| { |
| __shared_count::__release_shared(); |
| __release_weak(); |
| } |
| |
| void |
| __shared_weak_count::__release_weak() |
| { |
| if (decrement(__shared_weak_owners_) == -1) |
| __on_zero_shared_weak(); |
| } |
| |
| __shared_weak_count* |
| __shared_weak_count::lock() |
| { |
| long object_owners = __shared_owners_; |
| while (object_owners != -1) |
| { |
| if (__sync_bool_compare_and_swap(&__shared_owners_, |
| object_owners, |
| object_owners+1)) |
| { |
| __add_weak(); |
| return this; |
| } |
| object_owners = __shared_owners_; |
| } |
| return 0; |
| } |
| |
| #ifndef _LIBCPP_NO_RTTI |
| |
| const void* |
| __shared_weak_count::__get_deleter(const type_info&) const |
| { |
| return 0; |
| } |
| |
| #endif |
| |
| void |
| declare_reachable(void*) |
| { |
| } |
| |
| void |
| declare_no_pointers(char*, size_t) |
| { |
| } |
| |
| void |
| undeclare_no_pointers(char*, size_t) |
| { |
| } |
| |
| pointer_safety |
| get_pointer_safety() |
| { |
| return pointer_safety::relaxed; |
| } |
| |
| void* |
| __undeclare_reachable(void* p) |
| { |
| return p; |
| } |
| |
| void* |
| align(size_t alignment, size_t size, void*& ptr, size_t& space) |
| { |
| void* r = nullptr; |
| if (size <= space) |
| { |
| char* p1 = static_cast<char*>(ptr); |
| char* p2 = (char*)((size_t)(p1 + (alignment - 1)) & -alignment); |
| ptrdiff_t d = p2 - p1; |
| if (d <= space - size) |
| { |
| r = p2; |
| ptr = r; |
| space -= d; |
| } |
| } |
| return r; |
| } |
| |
| _LIBCPP_END_NAMESPACE_STD |