generic-library/cxx
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Implement a few optimizations for vector push_back and insert. Fixes r10828365.

Browse Source 
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@150542 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Howard Hinnant
2012-02-15 00:41:34 +00:00
parent 5f3f35fe64
commit b0bfd9bdd6
3 changed files with 103 additions and 26 deletions
Download Patch File Download Diff File Expand all files Collapse all files

63
include/memory
View File

@@ -597,6 +597,7 @@ void* align(size_t alignment, size_t size, void*& ptr, size_t& space);
#include <__functional_base>
#include <iosfwd>
#include <tuple>
#include <cstring>
#if defined(_LIBCPP_NO_EXCEPTIONS)
#include <cassert>
#endif
@@ -1395,6 +1396,14 @@ struct __has_construct
{
};
#else // _LIBCPP_HAS_NO_VARIADICS
template <class _Alloc, class _Pointer, class _Args>
struct __has_construct
: false_type
{
};
#endif // _LIBCPP_HAS_NO_VARIADICS
template <class _Alloc, class _Pointer>
@@ -1524,6 +1533,60 @@ struct _LIBCPP_VISIBLE allocator_traits
__has_select_on_container_copy_construction<const allocator_type>(),
__a);}
template <class _Ptr>
_LIBCPP_INLINE_VISIBILITY
static
void
__construct_forward(allocator_type& __a, _Ptr __begin1, _Ptr __end1, _Ptr& __begin2)
{
for (; __begin1 != __end1; ++__begin1, ++__begin2)
construct(__a, _VSTD::__to_raw_pointer(__begin2), _VSTD::move_if_noexcept(*__begin1));
}
template <class _Tp>
_LIBCPP_INLINE_VISIBILITY
static
typename enable_if
<
(is_same<allocator_type, allocator<_Tp> >::value
|| !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
is_trivially_move_constructible<_Tp>::value,
void
>::type
__construct_forward(allocator_type& __a, _Tp* __begin1, _Tp* __end1, _Tp*& __begin2)
{
ptrdiff_t _Np = __end1 - __begin1;
_VSTD::memcpy(__begin2, __begin1, _Np * sizeof(_Tp));
__begin2 += _Np;
}
template <class _Ptr>
_LIBCPP_INLINE_VISIBILITY
static
void
__construct_backward(allocator_type& __a, _Ptr __begin1, _Ptr __end1, _Ptr& __end2)
{
while (__end1 != __begin1)
construct(__a, _VSTD::__to_raw_pointer(--__end2), _VSTD::move_if_noexcept(*--__end1));
}
template <class _Tp>
_LIBCPP_INLINE_VISIBILITY
static
typename enable_if
<
(is_same<allocator_type, allocator<_Tp> >::value
|| !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
is_trivially_move_constructible<_Tp>::value,
void
>::type
__construct_backward(allocator_type& __a, _Tp* __begin1, _Tp* __end1, _Tp*& __end2)
{
ptrdiff_t _Np = __end1 - __begin1;
__end2 -= _Np;
_VSTD::memcpy(__end2, __begin1, _Np * sizeof(_Tp));
}
private:
_LIBCPP_INLINE_VISIBILITY