From 5a118de8034b83d7843baa3524a53fa6af7b7abf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ion=20Gazta=C3=B1aga?= <igaztanaga@gmail.com>
Date: Fri, 13 May 2016 00:28:29 +0200
Subject: [PATCH] Added recursive inplace_stable_sort implementation

---
 include/boost/move/algo/detail/merge_sort.hpp | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/include/boost/move/algo/detail/merge_sort.hpp b/include/boost/move/algo/detail/merge_sort.hpp
index 8101fce..892639b 100644
--- a/include/boost/move/algo/detail/merge_sort.hpp
+++ b/include/boost/move/algo/detail/merge_sort.hpp
@@ -41,6 +41,21 @@ namespace movelib {
 
 static const unsigned MergeSortInsertionSortThreshold = 16;
 
+template <class RandIt, class Compare>
+void inplace_stable_sort(RandIt first, RandIt last, Compare comp)
+{
+   typedef typename iterator_traits<RandIt>::size_type  size_type;
+   if (size_type(last - first) <= size_type(MergeSortInsertionSortThreshold)) {
+      insertion_sort(first, last, comp);
+      return;
+   }
+   RandIt middle = first + (last - first) / 2;
+   inplace_stable_sort(first, middle, comp);
+   inplace_stable_sort(middle, last, comp);
+   merge_bufferless_ONlogN_recursive
+      (first, middle, last, size_type(middle - first), size_type(last - middle), comp);
+}
+
 // @endcond
 
 template<class RandIt, class RandIt2, class Compare>