[libcxx-commits] [libcxx] [libc++] Optimize vector::emplace_back slow path (PR #222016)

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git-clang-format --diff origin/main HEAD --extensions h -- libcxx/include/__numeric/saturation_arithmetic.h libcxx/include/__vector/vector.h --diff_from_common_commit
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``````````diff
diff --git a/libcxx/include/__vector/vector.h b/libcxx/include/__vector/vector.h
index c6b422e99..6910b5682 100644
--- a/libcxx/include/__vector/vector.h
+++ b/libcxx/include/__vector/vector.h
@@ -890,7 +890,7 @@ vector<_Tp, _Allocator>::__recommend(size_type __new_size) const {
   if (__new_size > __ms)
     this->__throw_length_error();
   const size_type __cap = capacity();
-  auto __doubled = std::__saturating_add(__cap, __cap);
+  auto __doubled        = std::__saturating_add(__cap, __cap);
   return std::min(std::max(__new_size, __doubled), __ms);
 }
 
@@ -1076,10 +1076,7 @@ vector<_Tp, _Alloc>::emplace_back(_Args&&... __args) {
         __alloc_traits::construct(__alloc, __ptr + __size, std::forward<_Args>(__largs)...);
         auto __guard = std::__make_exception_guard([&] { __alloc_traits::destroy(__alloc, __ptr + __size); });
         std::__uninitialized_allocator_relocate(
-            __alloc,
-            std::__to_address(__old_begin),
-            std::__to_address(__self.__layout_.__end_ptr()),
-            __ptr);
+            __alloc, std::__to_address(__old_begin), std::__to_address(__self.__layout_.__end_ptr()), __ptr);
         __guard.__complete();
         __self.__layout_.__set_layout(__allocation.ptr, __size + 1, __allocation.count);
         if ((__is_std_allocator_v<allocator_type> && !__libcpp_is_constant_evaluated()) || __old_begin)

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https://github.com/llvm/llvm-project/pull/222016