Reduce the number of move constructions when constructing a std::function. This fixes http://llvm.org/bugs/show_bug.cgi?id=12105.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@151652 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/functional b/include/functional
index f941df2..884a577 100644
--- a/include/functional
+++ b/include/functional
@@ -989,9 +989,23 @@
__compressed_pair<_Fp, _Alloc> __f_;
public:
_LIBCPP_INLINE_VISIBILITY
- explicit __func(_Fp __f) : __f_(_VSTD::move(__f)) {}
+ explicit __func(_Fp&& __f)
+ : __f_(piecewise_construct, _VSTD::forward_as_tuple(_VSTD::move(__f)),
+ _VSTD::forward_as_tuple()) {}
_LIBCPP_INLINE_VISIBILITY
- explicit __func(_Fp __f, _Alloc __a) : __f_(_VSTD::move(__f), _VSTD::move(__a)) {}
+ explicit __func(const _Fp& __f, const _Alloc& __a)
+ : __f_(piecewise_construct, _VSTD::forward_as_tuple(__f),
+ _VSTD::forward_as_tuple(__a)) {}
+
+ _LIBCPP_INLINE_VISIBILITY
+ explicit __func(const _Fp& __f, _Alloc&& __a)
+ : __f_(piecewise_construct, _VSTD::forward_as_tuple(__f),
+ _VSTD::forward_as_tuple(_VSTD::move(__a))) {}
+
+ _LIBCPP_INLINE_VISIBILITY
+ explicit __func(_Fp&& __f, _Alloc&& __a)
+ : __f_(piecewise_construct, _VSTD::forward_as_tuple(_VSTD::move(__f)),
+ _VSTD::forward_as_tuple(_VSTD::move(__a))) {}
virtual __base<_Rp(_ArgTypes...)>* __clone() const;
virtual void __clone(__base<_Rp(_ArgTypes...)>*) const;
virtual void destroy() _NOEXCEPT;