2010-03-19 Paolo Carlini <paolo.carlini@oracle.com>

	* include/bits/stl_algo.h (shuffle): Add, per D3056.
	(random_shuffle): Fix signature in C++0x mode.
	(lower_bound, __lg): Move...
	* include/bits/stl_algobase.h: ... here.
	* include/bits/algorithmfwd.h: Adjust.
	* include/parallel/algorithmfwd.h: Likewise.
	* include/parallel/algo.h: Likewise.
	* include/bits/hashtable_policy.h (__lower_bound): Remove,
	adjust callers.
	* include/tr1/hashtable_policy.h (__lower_bound): Likewise.
	* include/bits/random.tcc (__detail::__transform): Add,
	adjust std::transform callers; don't include <algorithm>.
	* testsuite/25_algorithms/shuffle/1.cc: Add.
	* testsuite/25_algorithms/shuffle/requirements/
	explicit_instantiation/2.cc: Likewise.
	* testsuite/25_algorithms/shuffle/requirements/
	explicit_instantiation/pod.cc: Likewise.

	* include/bits/random.h: Add comments.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@157564 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 125 insertions, 0 deletions

diff --git a/libstdc++-v3/include/bits/stl_algobase.h b/libstdc++-v3/include/bits/stl_algobase.h
index 3575279226b..1756966a5a1 100644
--- a/libstdc++-v3/include/bits/stl_algobase.h
+++ b/libstdc++-v3/include/bits/stl_algobase.h
@@ -938,6 +938,131 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
 							    __first2, __last2);
     }
 
+  /**
+   *  @brief Finds the first position in which @a val could be inserted
+   *         without changing the ordering.
+   *  @param  first   An iterator.
+   *  @param  last    Another iterator.
+   *  @param  val     The search term.
+   *  @return         An iterator pointing to the first element <em>not less
+   *                  than</em> @a val, or end() if every element is less than 
+   *                  @a val.
+   *  @ingroup binary_search_algorithms
+  */
+  template<typename _ForwardIterator, typename _Tp>
+    _ForwardIterator
+    lower_bound(_ForwardIterator __first, _ForwardIterator __last,
+		const _Tp& __val)
+    {
+      typedef typename iterator_traits<_ForwardIterator>::value_type
+	_ValueType;
+      typedef typename iterator_traits<_ForwardIterator>::difference_type
+	_DistanceType;
+
+      // concept requirements
+      __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
+      __glibcxx_function_requires(_LessThanOpConcept<_ValueType, _Tp>)
+      __glibcxx_requires_partitioned_lower(__first, __last, __val);
+
+      _DistanceType __len = std::distance(__first, __last);
+      _DistanceType __half;
+      _ForwardIterator __middle;
+
+      while (__len > 0)
+	{
+	  __half = __len >> 1;
+	  __middle = __first;
+	  std::advance(__middle, __half);
+	  if (*__middle < __val)
+	    {
+	      __first = __middle;
+	      ++__first;
+	      __len = __len - __half - 1;
+	    }
+	  else
+	    __len = __half;
+	}
+      return __first;
+    }
+
+  /**
+   *  @brief Finds the first position in which @a val could be inserted
+   *         without changing the ordering.
+   *  @ingroup binary_search_algorithms
+   *  @param  first   An iterator.
+   *  @param  last    Another iterator.
+   *  @param  val     The search term.
+   *  @param  comp    A functor to use for comparisons.
+   *  @return An iterator pointing to the first element <em>not less
+   *           than</em> @a val, or end() if every element is less
+   *           than @a val.
+   *  @ingroup binary_search_algorithms
+   *
+   *  The comparison function should have the same effects on ordering as
+   *  the function used for the initial sort.
+  */
+  template<typename _ForwardIterator, typename _Tp, typename _Compare>
+    _ForwardIterator
+    lower_bound(_ForwardIterator __first, _ForwardIterator __last,
+		const _Tp& __val, _Compare __comp)
+    {
+      typedef typename iterator_traits<_ForwardIterator>::value_type
+	_ValueType;
+      typedef typename iterator_traits<_ForwardIterator>::difference_type
+	_DistanceType;
+
+      // concept requirements
+      __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
+      __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
+				  _ValueType, _Tp>)
+      __glibcxx_requires_partitioned_lower_pred(__first, __last,
+						__val, __comp);
+
+      _DistanceType __len = std::distance(__first, __last);
+      _DistanceType __half;
+      _ForwardIterator __middle;
+
+      while (__len > 0)
+	{
+	  __half = __len >> 1;
+	  __middle = __first;
+	  std::advance(__middle, __half);
+	  if (__comp(*__middle, __val))
+	    {
+	      __first = __middle;
+	      ++__first;
+	      __len = __len - __half - 1;
+	    }
+	  else
+	    __len = __half;
+	}
+      return __first;
+    }
+
+  /// This is a helper function for the sort routines and for random.tcc.
+  //  Precondition: __n > 0.
+  template<typename _Size>
+    inline _Size
+    __lg(_Size __n)
+    {
+      _Size __k;
+      for (__k = 0; __n != 0; __n >>= 1)
+	++__k;
+      return __k - 1;
+    }
+
+  inline int
+  __lg(int __n)
+  { return sizeof(int) * __CHAR_BIT__  - 1 - __builtin_clz(__n); }
+
+  inline long
+  __lg(long __n)
+  { return sizeof(long) * __CHAR_BIT__ - 1 - __builtin_clzl(__n); }
+
+  inline long long
+  __lg(long long __n)
+  { return sizeof(long long) * __CHAR_BIT__ - 1 - __builtin_clzll(__n); }
+
 _GLIBCXX_END_NAMESPACE
 
 _GLIBCXX_BEGIN_NESTED_NAMESPACE(std, _GLIBCXX_STD_P)