import of libc++ 6.0.0

1 files changed, 11 insertions, 58 deletions

diff --git a/lib/libcxx/include/experimental/algorithm b/lib/libcxx/include/experimental/algorithm
index 3902111c54e..a6a28f07181 100644
--- a/lib/libcxx/include/experimental/algorithm
+++ b/lib/libcxx/include/experimental/algorithm
@@ -39,17 +39,18 @@ SampleIterator sample(PopulationIterator first, PopulationIterator last,
 #include <algorithm>
 #include <type_traits>
 
-#include <__undef_min_max>
-
 #include <__debug>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif
 
-_LIBCPP_BEGIN_NAMESPACE_LFTS
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
 
 
+_LIBCPP_BEGIN_NAMESPACE_LFTS
+
 template <class _ForwardIterator, class _Searcher>
 _LIBCPP_INLINE_VISIBILITY
 _ForwardIterator search(_ForwardIterator __f, _ForwardIterator __l, const _Searcher &__s)
@@ -58,63 +59,15 @@ _ForwardIterator search(_ForwardIterator __f, _ForwardIterator __l, const _Searc
 
 template <class _PopulationIterator, class _SampleIterator, class _Distance,
           class _UniformRandomNumberGenerator>
-_LIBCPP_INLINE_VISIBILITY
-_SampleIterator __sample(_PopulationIterator __first,
-                         _PopulationIterator __last, _SampleIterator __out,
-                         _Distance __n,
-                         _UniformRandomNumberGenerator &&__g,
-                         input_iterator_tag) {
-
-  _Distance __k = 0;
-  for (; __first != __last && __k < __n; ++__first, (void)++__k)
-    __out[__k] = *__first;
-  _Distance __sz = __k;
-  for (; __first != __last; ++__first, (void)++__k) {
-    _Distance __r = _VSTD::uniform_int_distribution<_Distance>(0, __k)(__g);
-    if (__r < __sz)
-      __out[__r] = *__first;
-  }
-  return __out + _VSTD::min(__n, __k);
-}
-
-template <class _PopulationIterator, class _SampleIterator, class _Distance,
-          class _UniformRandomNumberGenerator>
-_LIBCPP_INLINE_VISIBILITY
-_SampleIterator __sample(_PopulationIterator __first,
-                         _PopulationIterator __last, _SampleIterator __out,
-                         _Distance __n,
-                         _UniformRandomNumberGenerator &&__g,
-                         forward_iterator_tag) {
-  _Distance __unsampled_sz = _VSTD::distance(__first, __last);
-  for (__n = _VSTD::min(__n, __unsampled_sz); __n != 0; ++__first) {
-    _Distance __r =
-        _VSTD::uniform_int_distribution<_Distance>(0, --__unsampled_sz)(__g);
-    if (__r < __n) {
-      *__out++ = *__first;
-      --__n;
-    }
-  }
-  return __out;
-}
-
-template <class _PopulationIterator, class _SampleIterator, class _Distance,
-          class _UniformRandomNumberGenerator>
-_LIBCPP_INLINE_VISIBILITY
-_SampleIterator sample(_PopulationIterator __first,
-                         _PopulationIterator __last, _SampleIterator __out,
-                         _Distance __n, _UniformRandomNumberGenerator &&__g) {
-  typedef typename iterator_traits<_PopulationIterator>::iterator_category
-        _PopCategory;
-  typedef typename iterator_traits<_PopulationIterator>::difference_type
-        _Difference;
-  typedef typename common_type<_Distance, _Difference>::type _CommonType;
-  _LIBCPP_ASSERT(__n >= 0, "N must be a positive number.");
-  return _VSTD_LFTS::__sample(
-      __first, __last, __out, _CommonType(__n),
-      _VSTD::forward<_UniformRandomNumberGenerator>(__g),
-      _PopCategory());
+inline _LIBCPP_INLINE_VISIBILITY
+_SampleIterator sample(_PopulationIterator __first, _PopulationIterator __last,
+                       _SampleIterator __output_iter, _Distance __n,
+                       _UniformRandomNumberGenerator &&__g) {
+  return _VSTD::__sample(__first, __last, __output_iter, __n, __g);
 }
 
 _LIBCPP_END_NAMESPACE_LFTS
 
+_LIBCPP_POP_MACROS
+
 #endif /* _LIBCPP_EXPERIMENTAL_ALGORITHM */