diff --git a/libcxx/include/string b/libcxx/include/string
--- a/libcxx/include/string
+++ b/libcxx/include/string
@@ -1528,7 +1528,7 @@
         _LIBCPP_INLINE_VISIBILITY
         size_type __align_it(size_type __s) _NOEXCEPT
             {return (__s + (__a-1)) & ~(__a-1);}
-    enum {__alignment = 16, __min_long_capacity = 32 };
+    enum {__alignment = 16};
     static _LIBCPP_INLINE_VISIBILITY
     size_type __recommend(size_type __s) _NOEXCEPT
         {
@@ -1538,12 +1538,6 @@
         if (__guess == __min_cap) ++__guess;
         return __guess;
         }
-    static _LIBCPP_INLINE_VISIBILITY size_type
-        __recommend_cap(size_type __cap) _NOEXCEPT {
-      return __align_it < sizeof(value_type) < __alignment
-          ? __alignment / sizeof(value_type)
-          : 1 > (__cap);
-    }
 
     inline
     void __init(const value_type* __s, size_type __sz, size_type __reserve);
@@ -1668,29 +1662,13 @@
     basic_string& __assign_external(const value_type* __s);
     basic_string& __assign_external(const value_type* __s, size_type __n);
 
-    template <bool __is_short>
-    value_type* __resize(size_type __n);
-
-    inline value_type* __resize(size_type __n) {
-      return __is_long() ? __resize<false>(__n) : __resize<true>(__n);
-    }
-
-    inline value_type* __resize_small(size_type __n) _NOEXCEPT {
+    // Assigns the value in __s, guaranteed to be __n < __min_cap in length.
+    inline basic_string& __assign_short(const value_type* __s, size_type __n) {
       pointer __p = __is_long()
                         ? (__set_long_size(__n), __get_long_pointer())
                         : (__set_short_size(__n), __get_short_pointer());
+      traits_type::move(_VSTD::__to_address(__p), __s, __n);
       traits_type::assign(__p[__n], value_type());
-      return  _VSTD::__to_address(__p);
-    }
-
-    inline basic_string& __assign_small_length(const value_type* __s,
-                                               size_type __n) {
-      value_type* p = (__n < __min_cap) ? __resize_small(__n) : __resize(__n);
-      if (__builtin_constant_p(*__s)) {
-        traits_type::copy(p, __s, __n);
-      } else {
-        traits_type::move(p, __s, __n);
-      }
       return *this;
     }
 
@@ -2253,39 +2231,6 @@
     traits_type::assign(__p[__old_sz], value_type());
 }
 
-template <class _CharT, class _Traits, class _Allocator>
-template <bool __is_short>
-_CharT* basic_string<_CharT, _Traits, _Allocator>::__resize(size_type __n) {
-  size_type __old_cap = __is_short ? __min_cap : __get_long_cap();
-  pointer __old_p = __is_short ? __get_short_pointer() : __get_long_pointer();
-  if (__n < __old_cap) {
-    __is_short ? __set_short_size(__n) : __set_long_size(__n);
-    return _VSTD::__to_address(__old_p);
-  }
-
-  const size_type __ms = max_size();
-  if (__n > __ms) this->__throw_length_error();
-
-  size_type __new_cap;
-  if (__is_short) {
-    __new_cap = __recommend_cap(_VSTD::max<size_type>(
-        __n + 1, __min_long_capacity / sizeof(value_type)));
-  } else {
-    __new_cap = (__old_cap < __ms / 2 - __alignment)
-                    ? __recommend_cap(_VSTD::max(__n + 1, 2 * __old_cap))
-                    : __ms;
-  }
-  pointer __p = __alloc_traits::allocate(__alloc(), __new_cap);
-  __invalidate_all_iterators();
-  __set_long_pointer(__p);
-  __is_short ? __set_short_size(__n) : __set_long_size(__n);
-  __set_long_cap(__new_cap);
-  if (!__is_short) {
-    __alloc_traits::deallocate(__alloc(), __old_p, __old_cap);
-  }
-  return __p;
-}
-
 template <class _CharT, class _Traits, class _Allocator>
 void
 basic_string<_CharT, _Traits, _Allocator>::__grow_by(size_type __old_cap, size_type __delta_cap, size_type __old_sz,
@@ -2358,8 +2303,8 @@
 basic_string<_CharT, _Traits, _Allocator>::assign(const value_type* __s, size_type __n)
 {
     _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "string::assign received nullptr");
-    return (__builtin_constant_p(__n) && __n <= 128 / sizeof(value_type))
-               ? __assign_small_length(__s, __n)
+    return (_LIBCPP_BUILTIN_CONSTANT_P(__n) && __n < __min_cap)
+               ? __assign_short(__s, __n)
                : __assign_external(__s, __n);
 }
 
@@ -2556,8 +2501,8 @@
 basic_string<_CharT, _Traits, _Allocator>::assign(const value_type* __s)
 {
     _LIBCPP_ASSERT(__s != nullptr, "string::assign received nullptr");
-    return (__builtin_constant_p(*__s) && traits_type::length(__s) <= 128)
-               ? __assign_small_length(__s, traits_type::length(__s))
+    return (_LIBCPP_BUILTIN_CONSTANT_P(*__s) && traits_type::length(__s) <= 128)
+               ? __assign_short(__s, traits_type::length(__s))
                : __assign_external(__s);
 }
 // append