[committed] libstdc++: Remove unnecessary tag dispatching in std::vector
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Commit Message
Tested x86_64-linux. Pushed to trunk.
-- >8 --
There's no need to call a _M_xxx_dispatch function with a
statically-known __false_type tag, we can just directly call the
function that should be dispatched to. This will compile a tiny bit
faster and save a function call with optimization or inlining turned
off.
Also add the always_inline attribute to the __iterator_category helper
used for dispatching on the iterator category.
libstdc++-v3/ChangeLog:
* include/bits/stl_iterator_base_types.h (__iterator_category):
Add always_inline attribute.
* include/bits/stl_vector.h (assign(Iter, Iter)): Call
_M_assign_aux directly, instead of _M_assign_dispatch.
(insert(const_iterator, Iter, Iter)): Call _M_range_insert
directly instead of _M_insert_dispatch.
---
libstdc++-v3/include/bits/stl_iterator_base_types.h | 1 +
libstdc++-v3/include/bits/stl_vector.h | 6 +++---
2 files changed, 4 insertions(+), 3 deletions(-)
@@ -233,6 +233,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
* sugar for internal library use only.
*/
template<typename _Iter>
+ __attribute__((__always_inline__))
inline _GLIBCXX_CONSTEXPR
typename iterator_traits<_Iter>::iterator_category
__iterator_category(const _Iter&)
@@ -821,7 +821,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
_GLIBCXX20_CONSTEXPR
void
assign(_InputIterator __first, _InputIterator __last)
- { _M_assign_dispatch(__first, __last, __false_type()); }
+ { _M_assign_aux(__first, __last, std::__iterator_category(__first)); }
#else
template<typename _InputIterator>
void
@@ -1478,8 +1478,8 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
_InputIterator __last)
{
difference_type __offset = __position - cbegin();
- _M_insert_dispatch(begin() + __offset,
- __first, __last, __false_type());
+ _M_range_insert(begin() + __offset, __first, __last,
+ std::__iterator_category(__first));
return begin() + __offset;
}
#else