re PR libstdc++/51608 ([C++11] Unordered containers end(size_type) isn't constant time)

2011-12-29  François Dumont <fdumont@gcc.gnu.org>

	PR libstdc++/51608
	* include/bits/hashtable_policy.h (_Equal_helper<>): New, change the
	way the _Equal functor is used depending on whether hash code is
	cached or not.
	(_Ebo_helper<>): New helper type to introduce EBO when possible.
	(_Hash_code_base): Use _Ebo_helper to limit memory footprint. Move
	_Equal functor management...
	(_Hashtable_base): ...here, new, use _Equal_helper.
	(_Local_iterator_base<>, _Locale_iterator<>, _Locale_const_iterator<>):
	New, use _Hash_code_base, implementation of...
	* include/bits/hashtable.h (_Hashtable<>::local_iterator,
	_Hashtable<>::const_local_iterator): ...those. Add static assertions
	checking that some functors are empty depending on whether hash code
	is cache or not.
	(_Hashtable<>::_M_bucket_index): New overloads using current bucket
	count, use through out the _Hastable<> implementation.
	* include/bits/unordered_set.h (__unordered_set<>,
	__unordered_multiset<>): Cache hash code iff hash functor is not
	empty and not final.
	* include/bits/unordered_map.h (__unordered_map<>,
	__unordered_multimap<>): Likewise.
	* include/debug/unordered_map
	(unordered_map<>::_S_to_local, unordered_multimap<>::_S_to_local):
	Adapt to match new local iterator implementation.
	* include/debug/unordered_set (unordered_set<>::_S_to_local,
	unordered_multiset<>::_S_to_local): Likewise.
	* include/profile/unordered_map (unordered_map<>::_M_profile_destruct,
	unordered_multimap<>::_M_profile_destruct): Enhance thanks to usage of
	local iterators.
	* include/profile/unordered_set (unordered_set<>::_M_profile_destruct,
	unordered_multiset<>::_M_profile_destruct): Likewise.
	* testsuite_files/23_containers/unordered_set/instantiation_neg.cc:
	Fix error line.
	* testsuite_files/23_containers/unordered_set/final_hash.cc: New.
	* testsuite_files/23_containers/unordered_multiset/final_hash.cc: New.
	* testsuite_files/23_containers/unordered_map/final_hash.cc: New.
	* testsuite_files/23_containers/unordered_multimap/final_hash.cc: New.

From-SVN: r182727

libstdc++-v3/ChangeLog

+2011-12-29  François Dumont <fdumont@gcc.gnu.org>
+
+	PR libstdc++/51608
+	* include/bits/hashtable_policy.h (_Equal_helper<>): New, change the
+	way the _Equal functor is used depending on whether hash code is
+	cached or not.
+	(_Ebo_helper<>): New helper type to introduce EBO when possible.
+	(_Hash_code_base): Use _Ebo_helper to limit memory footprint. Move
+	_Equal functor management...
+	(_Hashtable_base): ...here, new, use _Equal_helper.
+	(_Local_iterator_base<>, _Locale_iterator<>, _Locale_const_iterator<>):
+	New, use _Hash_code_base, implementation of...
+	* include/bits/hashtable.h (_Hashtable<>::local_iterator,
+	_Hashtable<>::const_local_iterator): ...those. Add static assertions
+	checking that some functors are empty depending on whether hash code
+	is cache or not.
+	(_Hashtable<>::_M_bucket_index): New overloads using current bucket
+	count, use through out the _Hastable<> implementation.
+	* include/bits/unordered_set.h (__unordered_set<>,
+	__unordered_multiset<>): Cache hash code iff hash functor is not
+	empty and not final.
+	* include/bits/unordered_map.h (__unordered_map<>,
+	__unordered_multimap<>): Likewise.
+	* include/debug/unordered_map
+	(unordered_map<>::_S_to_local, unordered_multimap<>::_S_to_local):
+	Adapt to match new local iterator implementation.
+	* include/debug/unordered_set (unordered_set<>::_S_to_local,
+	unordered_multiset<>::_S_to_local): Likewise.
+	* include/profile/unordered_map (unordered_map<>::_M_profile_destruct,
+	unordered_multimap<>::_M_profile_destruct): Enhance thanks to usage of
+	local iterators.
+	* include/profile/unordered_set (unordered_set<>::_M_profile_destruct,
+	unordered_multiset<>::_M_profile_destruct): Likewise.
+	* testsuite_files/23_containers/unordered_set/instantiation_neg.cc:
+	Fix error line.
+	* testsuite_files/23_containers/unordered_set/final_hash.cc: New.
+	* testsuite_files/23_containers/unordered_multiset/final_hash.cc: New.
+	* testsuite_files/23_containers/unordered_map/final_hash.cc: New.
+	* testsuite_files/23_containers/unordered_multimap/final_hash.cc: New.
+
 2011-12-29  Jonathan Wakely  <jwakely.gcc@gmail.com>
 
 	PR libstdc++/51701

libstdc++-v3/include/bits/unordered_map.h

@@ -41,7 +41,8 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 	   class _Pred = std::equal_to<_Key>,
 	   class _Alloc = std::allocator<std::pair<const _Key, _Tp> >,
 	   bool __cache_hash_code =
-	     __not_<__and_<is_integral<_Key>,
+	     __not_<__and_<is_integral<_Key>, is_empty<_Hash>,
+			   integral_constant<bool, !__is_final(_Hash)>,
 			   __detail::__is_noexcept_hash<_Key, _Hash>>>::value>
     class __unordered_map
     : public _Hashtable<_Key, std::pair<const _Key, _Tp>, _Alloc,
@@ -112,7 +113,8 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 	   class _Pred = std::equal_to<_Key>,
 	   class _Alloc = std::allocator<std::pair<const _Key, _Tp> >,
 	   bool __cache_hash_code =
-	     __not_<__and_<is_integral<_Key>,
+	     __not_<__and_<is_integral<_Key>, is_empty<_Hash>,
+			   integral_constant<bool, !__is_final(_Hash)>,
 			   __detail::__is_noexcept_hash<_Key, _Hash>>>::value>
     class __unordered_multimap
     : public _Hashtable<_Key, std::pair<const _Key, _Tp>,

libstdc++-v3/include/bits/unordered_set.h

@@ -41,7 +41,8 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 	   class _Pred = std::equal_to<_Value>,
 	   class _Alloc = std::allocator<_Value>,
 	   bool __cache_hash_code =
-	     __not_<__and_<is_integral<_Value>,
+	     __not_<__and_<is_integral<_Value>, is_empty<_Hash>,
+			   integral_constant<bool, !__is_final(_Hash)>,
 			   __detail::__is_noexcept_hash<_Value, _Hash>>>::value>
     class __unordered_set
     : public _Hashtable<_Value, _Value, _Alloc,
@@ -124,7 +125,8 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 	   class _Pred = std::equal_to<_Value>,
 	   class _Alloc = std::allocator<_Value>,
 	   bool __cache_hash_code =
-	     __not_<__and_<is_integral<_Value>,
+	     __not_<__and_<is_integral<_Value>, is_empty<_Hash>,
+			   integral_constant<bool, !__is_final(_Hash)>,
 			   __detail::__is_noexcept_hash<_Value, _Hash>>>::value>
     class __unordered_multiset
     : public _Hashtable<_Value, _Value, _Alloc,

libstdc++-v3/include/debug/unordered_map

@@ -418,11 +418,19 @@ namespace __debug
 
       static _Base_local_iterator
       _S_to_local(_Base_iterator __it)
-      { return _Base_local_iterator(__it._M_cur); }
+      {
+        // The returned local iterator will not be incremented so we don't
+	// need to compute __it's node bucket
+	return _Base_local_iterator(__it._M_cur, 0, 0);
+      }
 
       static _Base_const_local_iterator
       _S_to_local(_Base_const_iterator __it)
-      { return _Base_const_local_iterator(__it._M_cur); }
+      {
+        // The returned local iterator will not be incremented so we don't
+	// need to compute __it's node bucket
+	return _Base_const_local_iterator(__it._M_cur, 0, 0);
+      }
     };
 
   template<typename _Key, typename _Tp, typename _Hash,
@@ -820,11 +828,19 @@ namespace __debug
 
       static _Base_local_iterator
       _S_to_local(_Base_iterator __it)
-      { return _Base_local_iterator(__it._M_cur); }
+      {
+        // The returned local iterator will not be incremented so we don't
+	// need to compute __it's node bucket
+	return _Base_local_iterator(__it._M_cur, 0, 0);
+      }
 
       static _Base_const_local_iterator
       _S_to_local(_Base_const_iterator __it)
-      { return _Base_const_local_iterator(__it._M_cur); }
+      {
+        // The returned local iterator will not be incremented so we don't
+	// need to compute __it's node bucket
+	return _Base_const_local_iterator(__it._M_cur, 0, 0);
+      }
     };
 
   template<typename _Key, typename _Tp, typename _Hash,

libstdc++-v3/include/debug/unordered_set

@@ -417,11 +417,19 @@ namespace __debug
 
       static _Base_local_iterator
       _S_to_local(_Base_iterator __it)
-      { return _Base_local_iterator(__it._M_cur); }
+      {
+        // The returned local iterator will not be incremented so we don't
+	// need to compute __it's node bucket
+	return _Base_local_iterator(__it._M_cur, 0, 0);
+      }
 
       static _Base_const_local_iterator
       _S_to_local(_Base_const_iterator __it)
-      { return _Base_const_local_iterator(__it._M_cur); }
+      {
+        // The returned local iterator will not be incremented so we don't
+	// need to compute __it's node bucket
+	return _Base_const_local_iterator(__it._M_cur, 0, 0);
+      }
     };
 
   template<typename _Value, typename _Hash, typename _Pred, typename _Alloc>
@@ -805,11 +813,19 @@ namespace __debug
 
       static _Base_local_iterator
       _S_to_local(_Base_iterator __it)
-      { return _Base_local_iterator(__it._M_cur); }
+      {
+        // The returned local iterator will not be incremented so we don't
+	// need to compute __it's node bucket
+	return _Base_local_iterator(__it._M_cur, 0, 0);
+      }
 
       static _Base_const_local_iterator
       _S_to_local(_Base_const_iterator __it)
-      { return _Base_const_local_iterator(__it._M_cur); }
+      {
+        // The returned local iterator will not be incremented so we don't
+	// need to compute __it's node bucket
+	return _Base_const_local_iterator(__it._M_cur, 0, 0);
+      }
     };
 
   template<typename _Value, typename _Hash, typename _Pred, typename _Alloc>

libstdc++-v3/include/profile/unordered_map

@@ -308,9 +308,9 @@ namespace __profile
 	while (__it != this->end())
 	  {
 	    size_type __bkt = this->bucket(__it->first);
-	    for (++__it; __it != this->end()
-			 && this->bucket(__it->first) == __bkt;
-		 ++__it)
+	    auto __lit = this->begin(__bkt);
+	    auto __lend = this->end(__bkt);
+	    for (++__it, ++__lit; __lit != __lend; ++__it, ++__lit)
 	      ++__chain;
 	    if (__chain)
 	      {
@@ -577,9 +577,9 @@ namespace __profile
 	while (__it != this->end())
 	  {
 	    size_type __bkt = this->bucket(__it->first);
-	    for (++__it; __it != this->end()
-			 && this->bucket(__it->first) == __bkt;
-		 ++__it)
+	    auto __lit = this->begin(__bkt);
+	    auto __lend = this->end(__bkt);
+	    for (++__it, ++__lit; __lit != __lend; ++__it, ++__lit)
 	      ++__chain;
 	    if (__chain)
 	      {

libstdc++-v3/include/profile/unordered_set

@@ -277,10 +277,10 @@ namespace __profile
 	while (__it != this->end())
 	  {
 	    size_type __bkt = this->bucket(*__it);
-	    for (++__it; __it != this->end() && this->bucket(*__it) == __bkt;
-		 ++__it)
+	    auto __lit = this->begin(__bkt);
+	    auto __lend = this->end(__bkt);
+	    for (++__it, ++__lit; __lit != __lend; ++__it, ++__lit)
 	      ++__chain;
-
 	    if (__chain)
 	      {
 		++__chain;
@@ -539,10 +539,10 @@ namespace __profile
 	while (__it != this->end())
 	  {
 	    size_type __bkt = this->bucket(*__it);
-	    for (++__it; __it != this->end() && this->bucket(*__it) == __bkt;
-		 ++__it)
+	    auto __lit = this->begin(__bkt);
+	    auto __lend = this->end(__bkt);
+	    for (++__it, ++__lit; __lit != __lend; ++__it, ++__lit)
 	      ++__chain;
-
 	    if (__chain)
 	      {
 		++__chain;

libstdc++-v3/testsuite/23_containers/unordered_map/final_hash.cc

+// { dg-do compile }
+// { dg-options "-std=gnu++0x" }
+
+// Copyright (C) 2011 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without Pred the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <string>
+#include <unordered_map>
+
+namespace
+{
+  template<typename _Tp>
+  struct final_hash final
+  {
+    std::size_t operator() (const _Tp&) const noexcept
+    { return 0; }
+  };
+}
+
+// A non-integral type:
+template class std::unordered_map<std::string, int, final_hash<std::string>>;
+
+// An integral type;
+template class std::unordered_map<int, int, final_hash<int>>;
+

libstdc++-v3/testsuite/23_containers/unordered_multimap/final_hash.cc

+// { dg-do compile }
+// { dg-options "-std=gnu++0x" }
+
+// Copyright (C) 2011 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without Pred the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <string>
+#include <unordered_map>
+
+namespace
+{
+  template<typename _Tp>
+  struct final_hash final
+  {
+    std::size_t operator() (const _Tp&) const noexcept
+    { return 0; }
+  };
+}
+
+// A non-integral type:
+template class std::unordered_multimap<std::string, int,
+				       final_hash<std::string>>;
+
+// An integral type;
+template class std::unordered_multimap<int, int, final_hash<int>>;
+

libstdc++-v3/testsuite/23_containers/unordered_multiset/final_hash.cc

+// { dg-do compile }
+// { dg-options "-std=gnu++0x" }
+
+// Copyright (C) 2011 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without Pred the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <string>
+#include <unordered_set>
+
+namespace
+{
+  template<typename _Tp>
+  struct final_hash final
+  {
+    std::size_t operator() (const _Tp&) const noexcept
+    { return 0; }
+  };
+}
+
+// A non-integral type:
+template class std::unordered_multiset<std::string, final_hash<std::string>>;
+
+// An integral type;
+template class std::unordered_multiset<int, final_hash<int>>;
+

libstdc++-v3/testsuite/23_containers/unordered_set/final_hash.cc

+// { dg-do compile }
+// { dg-options "-std=gnu++0x" }
+
+// Copyright (C) 2011 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without Pred the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <string>
+#include <unordered_set>
+
+namespace
+{
+  template<typename _Tp>
+  struct final_hash final
+  {
+    std::size_t operator() (const _Tp&) const noexcept
+    { return 0; }
+  };
+}
+
+// A non-integral type:
+template class std::unordered_set<std::string, final_hash<std::string>>;
+
+// An integral type;
+template class std::unordered_set<int, final_hash<int>>;
+

libstdc++-v3/testsuite/23_containers/unordered_set/instantiation_neg.cc

@@ -19,7 +19,7 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-// { dg-error "static assertion failed" "" { target *-*-* } 177 }
+// { dg-error "static assertion failed" "" { target *-*-* } 185 }
 
 #include <unordered_set>