diff --git a/libstdc++-v3/doc/xml/manual/parallel_mode.xml b/libstdc++-v3/doc/xml/manual/parallel_mode.xml
index fb439062feaa2dc1f1ac686198aa0e911b46e990..faea5a9e7f68cac79774e49057841a305865904d 100644
--- a/libstdc++-v3/doc/xml/manual/parallel_mode.xml
+++ b/libstdc++-v3/doc/xml/manual/parallel_mode.xml
@@ -575,24 +575,36 @@ This means that the actual parallelization strategy is chosen at run-time.
(Choosing the variants at compile-time will come soon.)
</para>
+<para>
+For the following algorithms in general, we have
+<code>__gnu_parallel::parallel_tag</code> and
+<code>__gnu_parallel::default_parallel_tag</code>, in addition to
+<code>__gnu_parallel::sequential_tag</code>.
+<code>__gnu_parallel::default_parallel_tag</code> chooses the default
+algorithm at compiletime, as does omitting the tag.
+<code>__gnu_parallel::parallel_tag</code> postpones the decision to runtime
+(see next section).
+For all tags, the number of threads desired for this call can optionally be
+passed to the respective tag's constructor.
+</para>
+
+<para>
+The <code>multiway_merge</code> algorithm comes with the additional choices,
+<code>__gnu_parallel::exact_tag</code> and
+<code>__gnu_parallel::sampling_tag</code>.
+Exact and sampling are the two available splitting strategies.
+</para>
+
<para>
For the <code>sort</code> and <code>stable_sort</code> algorithms, there are
-several possible choices,
-<code>__gnu_parallel::parallel_tag</code>,
-<code>__gnu_parallel::default_parallel_tag</code>,
+several additional choices, namely
<code>__gnu_parallel::multiway_mergesort_tag</code>,
<code>__gnu_parallel::multiway_mergesort_exact_tag</code>,
<code>__gnu_parallel::multiway_mergesort_sampling_tag</code>,
-<code>__gnu_parallel::quicksort_tag</code>,
+<code>__gnu_parallel::quicksort_tag</code>, and
<code>__gnu_parallel::balanced_quicksort_tag</code>.
-Multiway mergesort comes with two splitting strategies for merging, therefore
-the extra choice. If non is chosen, the default splitting strategy is selected.
-<code>__gnu_parallel::default_parallel_tag</code> chooses the default parallel
-sorting algorithm at runtime. <code>__gnu_parallel::parallel_tag</code>
-postpones the decision to runtime (see next section).
-The quicksort options cannot be used for <code>stable_sort</code>.
-For all tags, the number of threads desired for this call can optionally be
-passed to the tag's constructor.
+Multiway mergesort comes with the two splitting strategies for multi-way
+merging. The quicksort options cannot be used for <code>stable_sort</code>.
</para>
</sect3>
diff --git a/libstdc++-v3/include/parallel/merge.h b/libstdc++-v3/include/parallel/merge.h
index cabd5bd4de2ec598f6de8e8307c88256fff6d8fd..580b1479329e14fbab6808a5c2141b994c903b9a 100644
--- a/libstdc++-v3/include/parallel/merge.h
+++ b/libstdc++-v3/include/parallel/merge.h
@@ -254,11 +254,11 @@ namespace __gnu_parallel
RandomAccessIterator3
target_end = parallel_multiway_merge
< /* stable = */ true, /* sentinels = */ false>(
- seqs, seqs + 2, target, comp,
+ seqs, seqs + 2, target,
multiway_merge_exact_splitting
< /* stable = */ true, iterator_pair*,
Comparator, difference_type1>,
- max_length);
+ max_length, comp, omp_get_max_threads());
return target_end;
}
diff --git a/libstdc++-v3/include/parallel/multiway_merge.h b/libstdc++-v3/include/parallel/multiway_merge.h
index 37e99cdeb6a9adfdeacef3dac17ae99da9b61754..3c75c70f3c4eb60b64bd8ea2f920883fe472a79e 100644
--- a/libstdc++-v3/include/parallel/multiway_merge.h
+++ b/libstdc++-v3/include/parallel/multiway_merge.h
@@ -297,7 +297,7 @@ template<template<typename RAI, typename C> class iterator,
RandomAccessIteratorIterator seqs_begin,
RandomAccessIteratorIterator seqs_end,
RandomAccessIterator3 target,
- Comparator comp, _DifferenceTp length)
+ _DifferenceTp length, Comparator comp)
{
_GLIBCXX_CALL(length);
@@ -416,7 +416,7 @@ template<template<typename RAI, typename C> class iterator,
multiway_merge_4_variant(RandomAccessIteratorIterator seqs_begin,
RandomAccessIteratorIterator seqs_end,
RandomAccessIterator3 target,
- Comparator comp, _DifferenceTp length)
+ _DifferenceTp length, Comparator comp)
{
_GLIBCXX_CALL(length);
typedef _DifferenceTp difference_type;
@@ -540,8 +540,7 @@ template<typename LT,
multiway_merge_loser_tree(RandomAccessIteratorIterator seqs_begin,
RandomAccessIteratorIterator seqs_end,
RandomAccessIterator3 target,
- Comparator comp,
- _DifferenceTp length)
+ _DifferenceTp length, Comparator comp)
{
_GLIBCXX_CALL(length)
@@ -626,8 +625,8 @@ template<typename LT,
const typename std::iterator_traits<typename std::iterator_traits<
RandomAccessIteratorIterator>::value_type::first_type>::value_type&
sentinel,
- Comparator comp,
- _DifferenceTp length)
+ _DifferenceTp length,
+ Comparator comp)
{
_GLIBCXX_CALL(length)
typedef _DifferenceTp difference_type;
@@ -716,8 +715,8 @@ template<
const typename std::iterator_traits<typename std::iterator_traits<
RandomAccessIteratorIterator>::value_type::first_type>::value_type&
sentinel,
- Comparator comp,
- _DifferenceTp length)
+ _DifferenceTp length,
+ Comparator comp)
{
_GLIBCXX_CALL(length)
@@ -740,7 +739,7 @@ template<
target_end = multiway_merge_loser_tree_unguarded
<UnguardedLoserTree>
- (seqs_begin, seqs_end, target, sentinel, comp, length);
+ (seqs_begin, seqs_end, target, sentinel, length, comp);
#if _GLIBCXX_ASSERTIONS
_GLIBCXX_PARALLEL_ASSERT(target_end == target + length);
@@ -808,10 +807,10 @@ struct multiway_merge_3_variant_sentinel_switch
RandomAccessIteratorIterator seqs_begin,
RandomAccessIteratorIterator seqs_end,
RandomAccessIterator3 target,
- Comparator comp, _DifferenceTp length)
+ _DifferenceTp length, Comparator comp)
{
return multiway_merge_3_variant<guarded_iterator>(
- seqs_begin, seqs_end, target, comp, length);
+ seqs_begin, seqs_end, target, length, comp);
}
};
@@ -833,10 +832,10 @@ struct multiway_merge_3_variant_sentinel_switch
RandomAccessIteratorIterator seqs_begin,
RandomAccessIteratorIterator seqs_end,
RandomAccessIterator3 target,
- Comparator comp, _DifferenceTp length)
+ _DifferenceTp length, Comparator comp)
{
return multiway_merge_3_variant<unguarded_iterator>(
- seqs_begin, seqs_end, target, comp, length);
+ seqs_begin, seqs_end, target, length, comp);
}
};
@@ -857,10 +856,10 @@ struct multiway_merge_4_variant_sentinel_switch
RandomAccessIteratorIterator seqs_begin,
RandomAccessIteratorIterator seqs_end,
RandomAccessIterator3 target,
- Comparator comp, _DifferenceTp length)
+ _DifferenceTp length, Comparator comp)
{
return multiway_merge_4_variant<guarded_iterator>(
- seqs_begin, seqs_end, target, comp, length);
+ seqs_begin, seqs_end, target, length, comp);
}
};
@@ -882,10 +881,10 @@ struct multiway_merge_4_variant_sentinel_switch
RandomAccessIteratorIterator seqs_begin,
RandomAccessIteratorIterator seqs_end,
RandomAccessIterator3 target,
- Comparator comp, _DifferenceTp length)
+ _DifferenceTp length, Comparator comp)
{
return multiway_merge_4_variant<unguarded_iterator>(
- seqs_begin, seqs_end, target, comp, length);
+ seqs_begin, seqs_end, target, length, comp);
}
};
@@ -908,7 +907,7 @@ struct multiway_merge_k_variant_sentinel_switch
const typename std::iterator_traits<typename std::iterator_traits<
RandomAccessIteratorIterator>::value_type::first_type>::value_type&
sentinel,
- Comparator comp, _DifferenceTp length)
+ _DifferenceTp length, Comparator comp)
{
typedef typename std::iterator_traits<RandomAccessIteratorIterator>
::value_type::first_type
@@ -921,7 +920,7 @@ struct multiway_merge_k_variant_sentinel_switch
loser_tree_traits<value_type>::use_pointer
, LoserTreePointerUnguarded<stable, value_type, Comparator>
, LoserTreeUnguarded<stable, value_type, Comparator>
- >::__type>(seqs_begin, seqs_end, target, sentinel, comp, length);
+ >::__type>(seqs_begin, seqs_end, target, sentinel, length, comp);
}
};
@@ -945,7 +944,7 @@ struct multiway_merge_k_variant_sentinel_switch
const typename std::iterator_traits<typename std::iterator_traits<
RandomAccessIteratorIterator>::value_type::first_type>::value_type&
sentinel,
- Comparator comp, _DifferenceTp length)
+ _DifferenceTp length, Comparator comp)
{
typedef typename std::iterator_traits<RandomAccessIteratorIterator>
::value_type::first_type
@@ -958,7 +957,7 @@ struct multiway_merge_k_variant_sentinel_switch
loser_tree_traits<value_type>::use_pointer
, LoserTreePointer<stable, value_type, Comparator>
, LoserTree<stable, value_type, Comparator>
- >::__type >(seqs_begin, seqs_end, target, comp, length);
+ >::__type >(seqs_begin, seqs_end, target, length, comp);
}
};
@@ -990,7 +989,7 @@ template<
const typename std::iterator_traits<typename std::iterator_traits<
RandomAccessIteratorIterator>::value_type::first_type>::value_type&
sentinel,
- Comparator comp, _DifferenceTp length)
+ _DifferenceTp length, Comparator comp)
{
_GLIBCXX_CALL(length)
@@ -1043,7 +1042,7 @@ template<
, RandomAccessIteratorIterator
, RandomAccessIterator3
, _DifferenceTp
- , Comparator>()(seqs_begin, seqs_end, target, comp, length);
+ , Comparator>()(seqs_begin, seqs_end, target, length, comp);
break;
case 4:
return_target = multiway_merge_4_variant_sentinel_switch<
@@ -1051,7 +1050,7 @@ template<
, RandomAccessIteratorIterator
, RandomAccessIterator3
, _DifferenceTp
- , Comparator>()(seqs_begin, seqs_end, target, comp, length);
+ , Comparator>()(seqs_begin, seqs_end, target, length, comp);
break;
default:
return_target = multiway_merge_k_variant_sentinel_switch<
@@ -1060,8 +1059,7 @@ template<
, RandomAccessIteratorIterator
, RandomAccessIterator3
, _DifferenceTp
- , Comparator>()
- (seqs_begin, seqs_end, target, sentinel, comp, length);
+ , Comparator>()(seqs_begin, seqs_end, target, sentinel, length, comp);
break;
}
#if _GLIBCXX_ASSERTIONS
@@ -1108,8 +1106,7 @@ template<
void multiway_merge_sampling_splitting(
RandomAccessIteratorIterator seqs_begin,
RandomAccessIteratorIterator seqs_end,
- Comparator comp, difference_type length,
- difference_type total_length,
+ difference_type length, difference_type total_length, Comparator comp,
std::vector<std::pair<difference_type, difference_type> > *pieces)
{
typedef typename std::iterator_traits<RandomAccessIteratorIterator>
@@ -1190,9 +1187,7 @@ template<
void multiway_merge_exact_splitting(
RandomAccessIteratorIterator seqs_begin,
RandomAccessIteratorIterator seqs_end,
- Comparator comp,
- difference_type length,
- difference_type total_length,
+ difference_type length, difference_type total_length, Comparator comp,
std::vector<std::pair<difference_type, difference_type> > *pieces)
{
typedef typename std::iterator_traits<RandomAccessIteratorIterator>
@@ -1297,9 +1292,10 @@ template<
parallel_multiway_merge(RandomAccessIteratorIterator seqs_begin,
RandomAccessIteratorIterator seqs_end,
RandomAccessIterator3 target,
- Comparator comp,
Splitter splitter,
- _DifferenceTp length)
+ _DifferenceTp length,
+ Comparator comp,
+ thread_index_t num_threads)
{
#if _GLIBCXX_ASSERTIONS
_GLIBCXX_PARALLEL_ASSERT(seqs_end - seqs_begin > 1);
@@ -1347,8 +1343,8 @@ template<
std::vector<std::pair<difference_type, difference_type> >* pieces;
- thread_index_t num_threads = static_cast<thread_index_t>
- (std::min<difference_type>(get_max_threads(), total_length));
+ num_threads = static_cast<thread_index_t>
+ (std::min<difference_type>(num_threads, total_length));
# pragma omp parallel num_threads (num_threads)
{
@@ -1365,8 +1361,8 @@ template<
__gnu_parallel::_Settings::get().merge_oversampling *
num_threads;
- splitter(ne_seqs, ne_seqs + k, comp, length, total_length,
- pieces);
+ splitter(ne_seqs, ne_seqs + k, length, total_length,
+ comp, pieces);
} //single
thread_index_t iam = omp_get_thread_num();
@@ -1389,7 +1385,7 @@ template<
if(length > target_position)
sequential_multiway_merge<stable, sentinels>(
chunks, chunks + k, target + target_position,
- *(seqs_begin->second), comp, length - target_position);
+ *(seqs_begin->second), length - target_position, comp);
delete[] chunks;
} // parallel
@@ -1481,6 +1477,7 @@ template<
*
* @return end iterator of output sequence
*/
+// multiway_merge
// public interface
template<
typename RandomAccessIteratorPairIterator
@@ -1491,49 +1488,7 @@ RandomAccessIteratorOut
multiway_merge(RandomAccessIteratorPairIterator seqs_begin
, RandomAccessIteratorPairIterator seqs_end
, RandomAccessIteratorOut target
- , Comparator comp, _DifferenceTp length)
-{
- typedef _DifferenceTp difference_type;
- _GLIBCXX_CALL(seqs_end - seqs_begin)
-
- // catch special case: no sequences
- if (seqs_begin == seqs_end)
- return target;
-
- // Execute merge; maybe parallel, depending on the number of merged
- // elements and the number of sequences and global thresholds in
- // Settings.
- if ((seqs_end - seqs_begin > 1) &&
- _GLIBCXX_PARALLEL_CONDITION(
- ((seqs_end - seqs_begin) >=
- __gnu_parallel::_Settings::get().multiway_merge_minimal_k)
- && ((sequence_index_t)length >=
- __gnu_parallel::_Settings::get().multiway_merge_minimal_n)))
- return parallel_multiway_merge
- </* stable = */ false, /* sentinels = */ false>
- (seqs_begin, seqs_end, target, comp,
- multiway_merge_sampling_splitting</* stable = */ false,
- typename std::iterator_traits<RandomAccessIteratorPairIterator>
- ::value_type*, Comparator, _DifferenceTp>,
- static_cast<difference_type>(length));
- else
- return sequential_multiway_merge
- </* stable = */false, /* sentinels = */ false>(
- seqs_begin, seqs_end,
- target, *(seqs_begin->second), comp, length);
-}
-
-// public interface
-template<
- typename RandomAccessIteratorPairIterator
- , typename RandomAccessIteratorOut
- , typename _DifferenceTp
- , typename Comparator>
-RandomAccessIteratorOut
-multiway_merge(RandomAccessIteratorPairIterator seqs_begin
- , RandomAccessIteratorPairIterator seqs_end
- , RandomAccessIteratorOut target
- , Comparator comp, _DifferenceTp length
+ , _DifferenceTp length, Comparator comp
, __gnu_parallel::sequential_tag)
{
typedef _DifferenceTp difference_type;
@@ -1546,10 +1501,10 @@ multiway_merge(RandomAccessIteratorPairIterator seqs_begin
// Execute multiway merge *sequentially*.
return sequential_multiway_merge
</* stable = */ false, /* sentinels = */ false>
- (seqs_begin, seqs_end, target, *(seqs_begin->second), comp, length);
+ (seqs_begin, seqs_end, target, *(seqs_begin->second), length, comp);
}
-//public interface
+// public interface
template<
typename RandomAccessIteratorPairIterator
, typename RandomAccessIteratorOut
@@ -1559,8 +1514,8 @@ RandomAccessIteratorOut
multiway_merge(RandomAccessIteratorPairIterator seqs_begin
, RandomAccessIteratorPairIterator seqs_end
, RandomAccessIteratorOut target
- , Comparator comp, _DifferenceTp length
- , __gnu_parallel::exact_tag)
+ , _DifferenceTp length, Comparator comp
+ , __gnu_parallel::exact_tag tag)
{
typedef _DifferenceTp difference_type;
_GLIBCXX_CALL(seqs_end - seqs_begin)
@@ -1580,17 +1535,15 @@ multiway_merge(RandomAccessIteratorPairIterator seqs_begin
__gnu_parallel::_Settings::get().multiway_merge_minimal_n)))
return parallel_multiway_merge
</* stable = */ false, /* sentinels = */ false>(
- seqs_begin, seqs_end,
- target, comp,
+ seqs_begin, seqs_end, target,
multiway_merge_exact_splitting</* stable = */ false,
typename std::iterator_traits<RandomAccessIteratorPairIterator>
::value_type*, Comparator, _DifferenceTp>,
- static_cast<difference_type>(length));
+ static_cast<difference_type>(length), comp, tag.get_num_threads());
else
return sequential_multiway_merge
</* stable = */ false, /* sentinels = */ false>(
- seqs_begin, seqs_end,
- target, *(seqs_begin->second), comp, length);
+ seqs_begin, seqs_end, target, *(seqs_begin->second), length, comp);
}
// public interface
@@ -1600,10 +1553,11 @@ template<
, typename _DifferenceTp
, typename Comparator>
RandomAccessIteratorOut
-stable_multiway_merge(RandomAccessIteratorPairIterator seqs_begin
+multiway_merge(RandomAccessIteratorPairIterator seqs_begin
, RandomAccessIteratorPairIterator seqs_end
, RandomAccessIteratorOut target
- , Comparator comp, _DifferenceTp length)
+ , _DifferenceTp length, Comparator comp
+ , __gnu_parallel::sampling_tag tag)
{
typedef _DifferenceTp difference_type;
_GLIBCXX_CALL(seqs_end - seqs_begin)
@@ -1618,24 +1572,59 @@ stable_multiway_merge(RandomAccessIteratorPairIterator seqs_begin
if ((seqs_end - seqs_begin > 1) &&
_GLIBCXX_PARALLEL_CONDITION(
((seqs_end - seqs_begin) >=
- __gnu_parallel::_Settings::get().multiway_merge_minimal_k)
+ __gnu_parallel::_Settings::get().multiway_merge_minimal_k)
&& ((sequence_index_t)length >=
__gnu_parallel::_Settings::get().multiway_merge_minimal_n)))
return parallel_multiway_merge
- </* stable = */ true, /* sentinels = */ false>(
+ </* stable = */ false, /* sentinels = */ false>(
seqs_begin, seqs_end,
- target, comp,
- multiway_merge_sampling_splitting</* stable = */ true,
+ target,
+ multiway_merge_exact_splitting</* stable = */ false,
typename std::iterator_traits<RandomAccessIteratorPairIterator>
::value_type*, Comparator, _DifferenceTp>,
- static_cast<difference_type>(length));
+ static_cast<difference_type>(length), comp, tag.get_num_threads());
else
return sequential_multiway_merge
- </* stable = */ true, /* sentinels = */ false>(
+ </* stable = */ false, /* sentinels = */ false>(
seqs_begin, seqs_end,
- target, *(seqs_begin->second), comp, length);
+ target, *(seqs_begin->second), length, comp);
}
+// public interface
+template<
+ typename RandomAccessIteratorPairIterator
+ , typename RandomAccessIteratorOut
+ , typename _DifferenceTp
+ , typename Comparator>
+RandomAccessIteratorOut
+multiway_merge(RandomAccessIteratorPairIterator seqs_begin
+ , RandomAccessIteratorPairIterator seqs_end
+ , RandomAccessIteratorOut target
+ , _DifferenceTp length, Comparator comp
+ , parallel_tag tag = parallel_tag(0))
+{
+ return multiway_merge(seqs_begin, seqs_end, target, length, comp,
+ exact_tag(tag.get_num_threads()));
+}
+
+// public interface
+template<
+ typename RandomAccessIteratorPairIterator
+ , typename RandomAccessIteratorOut
+ , typename _DifferenceTp
+ , typename Comparator>
+RandomAccessIteratorOut
+multiway_merge(RandomAccessIteratorPairIterator seqs_begin
+ , RandomAccessIteratorPairIterator seqs_end
+ , RandomAccessIteratorOut target
+ , _DifferenceTp length, Comparator comp
+ , default_parallel_tag tag)
+{
+ return multiway_merge(seqs_begin, seqs_end, target, length, comp,
+ exact_tag(tag.get_num_threads()));
+}
+
+// stable_multiway_merge
// public interface
template<
typename RandomAccessIteratorPairIterator
@@ -1646,7 +1635,7 @@ RandomAccessIteratorOut
stable_multiway_merge(RandomAccessIteratorPairIterator seqs_begin
, RandomAccessIteratorPairIterator seqs_end
, RandomAccessIteratorOut target
- , Comparator comp, _DifferenceTp length
+ , _DifferenceTp length, Comparator comp
, __gnu_parallel::sequential_tag)
{
typedef _DifferenceTp difference_type;
@@ -1659,7 +1648,7 @@ stable_multiway_merge(RandomAccessIteratorPairIterator seqs_begin
// Execute multiway merge *sequentially*.
return sequential_multiway_merge
</* stable = */ true, /* sentinels = */ false>
- (seqs_begin, seqs_end, target, *(seqs_begin->second), comp, length);
+ (seqs_begin, seqs_end, target, *(seqs_begin->second), length, comp);
}
// public interface
@@ -1672,8 +1661,8 @@ RandomAccessIteratorOut
stable_multiway_merge(RandomAccessIteratorPairIterator seqs_begin
, RandomAccessIteratorPairIterator seqs_end
, RandomAccessIteratorOut target
- , Comparator comp, _DifferenceTp length
- , __gnu_parallel::exact_tag)
+ , _DifferenceTp length, Comparator comp
+ , __gnu_parallel::exact_tag tag)
{
typedef _DifferenceTp difference_type;
_GLIBCXX_CALL(seqs_end - seqs_begin)
@@ -1694,17 +1683,95 @@ stable_multiway_merge(RandomAccessIteratorPairIterator seqs_begin
return parallel_multiway_merge
</* stable = */ true, /* sentinels = */ false>(
seqs_begin, seqs_end,
- target, comp,
- multiway_merge_exact_splitting
- </* stable = */ true,
- typename std::iterator_traits<RandomAccessIteratorPairIterator>
- ::value_type*, Comparator, _DifferenceTp>,
- static_cast<difference_type>(length));
+ target,
+ multiway_merge_exact_splitting</* stable = */ true,
+ typename std::iterator_traits<RandomAccessIteratorPairIterator>
+ ::value_type*, Comparator, _DifferenceTp>,
+ static_cast<difference_type>(length), comp, tag.get_num_threads());
else
return sequential_multiway_merge</* stable = */ true,
/* sentinels = */ false>(
seqs_begin, seqs_end,
- target, *(seqs_begin->second), comp, length);
+ target, *(seqs_begin->second), length, comp);
+}
+
+// public interface
+template<
+ typename RandomAccessIteratorPairIterator
+ , typename RandomAccessIteratorOut
+ , typename _DifferenceTp
+ , typename Comparator>
+RandomAccessIteratorOut
+stable_multiway_merge(RandomAccessIteratorPairIterator seqs_begin
+ , RandomAccessIteratorPairIterator seqs_end
+ , RandomAccessIteratorOut target
+ , _DifferenceTp length, Comparator comp
+ , sampling_tag tag)
+{
+ typedef _DifferenceTp difference_type;
+ _GLIBCXX_CALL(seqs_end - seqs_begin)
+
+ // catch special case: no sequences
+ if (seqs_begin == seqs_end)
+ return target;
+
+ // Execute merge; maybe parallel, depending on the number of merged
+ // elements and the number of sequences and global thresholds in
+ // Settings.
+ if ((seqs_end - seqs_begin > 1) &&
+ _GLIBCXX_PARALLEL_CONDITION(
+ ((seqs_end - seqs_begin) >=
+ __gnu_parallel::_Settings::get().multiway_merge_minimal_k)
+ && ((sequence_index_t)length >=
+ __gnu_parallel::_Settings::get().multiway_merge_minimal_n)))
+ return parallel_multiway_merge
+ </* stable = */ true, /* sentinels = */ false>(
+ seqs_begin, seqs_end,
+ target,
+ multiway_merge_sampling_splitting</* stable = */ true,
+ typename std::iterator_traits<RandomAccessIteratorPairIterator>
+ ::value_type*, Comparator, _DifferenceTp>,
+ static_cast<difference_type>(length), comp, tag.get_num_threads());
+ else
+ return sequential_multiway_merge
+ </* stable = */ true, /* sentinels = */ false>(
+ seqs_begin, seqs_end,
+ target, *(seqs_begin->second), length, comp);
+}
+
+
+// public interface
+template<
+ typename RandomAccessIteratorPairIterator
+ , typename RandomAccessIteratorOut
+ , typename _DifferenceTp
+ , typename Comparator>
+RandomAccessIteratorOut
+stable_multiway_merge(RandomAccessIteratorPairIterator seqs_begin
+ , RandomAccessIteratorPairIterator seqs_end
+ , RandomAccessIteratorOut target
+ , _DifferenceTp length, Comparator comp
+ , parallel_tag tag = parallel_tag(0))
+{
+ return stable_multiway_merge(seqs_begin, seqs_end, target, length, comp,
+ exact_tag(tag.get_num_threads()));
+}
+
+// public interface
+template<
+ typename RandomAccessIteratorPairIterator
+ , typename RandomAccessIteratorOut
+ , typename _DifferenceTp
+ , typename Comparator>
+RandomAccessIteratorOut
+stable_multiway_merge(RandomAccessIteratorPairIterator seqs_begin
+ , RandomAccessIteratorPairIterator seqs_end
+ , RandomAccessIteratorOut target
+ , _DifferenceTp length, Comparator comp
+ , default_parallel_tag tag)
+{
+ return stable_multiway_merge(seqs_begin, seqs_end, target, length, comp,
+ exact_tag(tag.get_num_threads()));
}
/**
@@ -1782,6 +1849,7 @@ stable_multiway_merge(RandomAccessIteratorPairIterator seqs_begin
*
* @return end iterator of output sequence
*/
+// multiway_merge_sentinels
// public interface
template<
typename RandomAccessIteratorPairIterator
@@ -1792,50 +1860,7 @@ RandomAccessIteratorOut
multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
, RandomAccessIteratorPairIterator seqs_end
, RandomAccessIteratorOut target
- , Comparator comp, _DifferenceTp length)
-{
- typedef _DifferenceTp difference_type;
- _GLIBCXX_CALL(seqs_end - seqs_begin)
-
- // catch special case: no sequences
- if (seqs_begin == seqs_end)
- return target;
-
- // Execute merge; maybe parallel, depending on the number of merged
- // elements and the number of sequences and global thresholds in
- // Settings.
- if ((seqs_end - seqs_begin > 1) &&
- _GLIBCXX_PARALLEL_CONDITION(
- ((seqs_end - seqs_begin) >=
- __gnu_parallel::_Settings::get().multiway_merge_minimal_k)
- && ((sequence_index_t)length >=
- __gnu_parallel::_Settings::get().multiway_merge_minimal_n)))
- return parallel_multiway_merge
- </* stable = */ false, /* sentinels = */ true>
- (seqs_begin, seqs_end, target, comp,
- multiway_merge_sampling_splitting
- </* stable = */ false,
- typename std::iterator_traits<RandomAccessIteratorPairIterator>
- ::value_type*, Comparator, _DifferenceTp>,
- static_cast<difference_type>(length));
- else
- return sequential_multiway_merge
- </* stable = */false, /* sentinels = */ true>(
- seqs_begin, seqs_end,
- target, *(seqs_begin->second), comp, length);
-}
-
-//public interface
-template<
- typename RandomAccessIteratorPairIterator
- , typename RandomAccessIteratorOut
- , typename _DifferenceTp
- , typename Comparator>
-RandomAccessIteratorOut
-multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
- , RandomAccessIteratorPairIterator seqs_end
- , RandomAccessIteratorOut target
- , Comparator comp, _DifferenceTp length
+ , _DifferenceTp length, Comparator comp
, __gnu_parallel::sequential_tag)
{
typedef _DifferenceTp difference_type;
@@ -1848,7 +1873,8 @@ multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
// Execute multiway merge *sequentially*.
return sequential_multiway_merge
</* stable = */ false, /* sentinels = */ true>
- (seqs_begin, seqs_end, target, *(seqs_begin->second), comp, length);
+ (seqs_begin, seqs_end,
+ target, *(seqs_begin->second), length, comp);
}
// public interface
@@ -1861,8 +1887,8 @@ RandomAccessIteratorOut
multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
, RandomAccessIteratorPairIterator seqs_end
, RandomAccessIteratorOut target
- , Comparator comp, _DifferenceTp length
- , __gnu_parallel::exact_tag)
+ , _DifferenceTp length, Comparator comp
+ , __gnu_parallel::exact_tag tag)
{
typedef _DifferenceTp difference_type;
_GLIBCXX_CALL(seqs_end - seqs_begin)
@@ -1883,17 +1909,16 @@ multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
return parallel_multiway_merge
</* stable = */ false, /* sentinels = */ true>(
seqs_begin, seqs_end,
- target, comp,
- multiway_merge_exact_splitting
- </* stable = */ false,
- typename std::iterator_traits<RandomAccessIteratorPairIterator>
- ::value_type*, Comparator, _DifferenceTp>,
- static_cast<difference_type>(length));
+ target,
+ multiway_merge_exact_splitting</* stable = */ false,
+ typename std::iterator_traits<RandomAccessIteratorPairIterator>
+ ::value_type*, Comparator, _DifferenceTp>,
+ static_cast<difference_type>(length), comp, tag.get_num_threads());
else
return sequential_multiway_merge
</* stable = */ false, /* sentinels = */ true>(
seqs_begin, seqs_end,
- target, *(seqs_begin->second), comp, length);
+ target, *(seqs_begin->second), length, comp);
}
// public interface
@@ -1903,10 +1928,11 @@ template<
, typename _DifferenceTp
, typename Comparator>
RandomAccessIteratorOut
-stable_multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
+multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
, RandomAccessIteratorPairIterator seqs_end
, RandomAccessIteratorOut target
- , Comparator comp, _DifferenceTp length)
+ , _DifferenceTp length, Comparator comp
+ , sampling_tag tag)
{
typedef _DifferenceTp difference_type;
_GLIBCXX_CALL(seqs_end - seqs_begin)
@@ -1925,21 +1951,54 @@ stable_multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
&& ((sequence_index_t)length >=
__gnu_parallel::_Settings::get().multiway_merge_minimal_n)))
return parallel_multiway_merge
- </* stable = */ true, /* sentinels = */ true>(
- seqs_begin, seqs_end,
- target, comp,
- multiway_merge_sampling_splitting
- </* stable = */ true,
- typename std::iterator_traits<RandomAccessIteratorPairIterator>
- ::value_type*, Comparator, _DifferenceTp>,
- static_cast<difference_type>(length));
+ </* stable = */ false, /* sentinels = */ true>
+ (seqs_begin, seqs_end, target,
+ multiway_merge_sampling_splitting</* stable = */ false,
+ typename std::iterator_traits<RandomAccessIteratorPairIterator>
+ ::value_type*, Comparator, _DifferenceTp>,
+ static_cast<difference_type>(length), comp, tag.get_num_threads());
else
return sequential_multiway_merge
- </* stable = */ true, /* sentinels = */ true>(
+ </* stable = */false, /* sentinels = */ true>(
seqs_begin, seqs_end,
- target, *(seqs_begin->second), comp, length);
+ target, *(seqs_begin->second), length, comp);
+}
+
+// public interface
+template<
+ typename RandomAccessIteratorPairIterator
+ , typename RandomAccessIteratorOut
+ , typename _DifferenceTp
+ , typename Comparator>
+RandomAccessIteratorOut
+multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
+ , RandomAccessIteratorPairIterator seqs_end
+ , RandomAccessIteratorOut target
+ , _DifferenceTp length, Comparator comp
+ , parallel_tag tag = parallel_tag(0))
+{
+ return multiway_merge_sentinels(seqs_begin, seqs_end, target, length, comp,
+ exact_tag(tag.get_num_threads()));
+}
+
+// public interface
+template<
+ typename RandomAccessIteratorPairIterator
+ , typename RandomAccessIteratorOut
+ , typename _DifferenceTp
+ , typename Comparator>
+RandomAccessIteratorOut
+multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
+ , RandomAccessIteratorPairIterator seqs_end
+ , RandomAccessIteratorOut target
+ , _DifferenceTp length, Comparator comp
+ , default_parallel_tag tag)
+{
+ return multiway_merge_sentinels(seqs_begin, seqs_end, target, length, comp,
+ exact_tag(tag.get_num_threads()));
}
+// stable_multiway_merge_sentinels
// public interface
template<
typename RandomAccessIteratorPairIterator
@@ -1950,7 +2009,7 @@ RandomAccessIteratorOut
stable_multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
, RandomAccessIteratorPairIterator seqs_end
, RandomAccessIteratorOut target
- , Comparator comp, _DifferenceTp length
+ , _DifferenceTp length, Comparator comp
, __gnu_parallel::sequential_tag)
{
typedef _DifferenceTp difference_type;
@@ -1963,7 +2022,7 @@ stable_multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
// Execute multiway merge *sequentially*.
return sequential_multiway_merge
</* stable = */ true, /* sentinels = */ true>
- (seqs_begin, seqs_end, target, *(seqs_begin->second), comp, length);
+ (seqs_begin, seqs_end, target, *(seqs_begin->second), length, comp);
}
// public interface
@@ -1976,8 +2035,8 @@ RandomAccessIteratorOut
stable_multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
, RandomAccessIteratorPairIterator seqs_end
, RandomAccessIteratorOut target
- , Comparator comp, _DifferenceTp length
- , __gnu_parallel::exact_tag)
+ , _DifferenceTp length, Comparator comp
+ , __gnu_parallel::exact_tag tag)
{
typedef _DifferenceTp difference_type;
_GLIBCXX_CALL(seqs_end - seqs_begin)
@@ -1998,17 +2057,93 @@ stable_multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
return parallel_multiway_merge
</* stable = */ true, /* sentinels = */ true>(
seqs_begin, seqs_end,
- target, comp,
- multiway_merge_exact_splitting
- </* stable = */ true,
- typename std::iterator_traits<RandomAccessIteratorPairIterator>
- ::value_type*, Comparator, _DifferenceTp>,
- static_cast<difference_type>(length));
+ target,
+ multiway_merge_exact_splitting</* stable = */ true,
+ typename std::iterator_traits<RandomAccessIteratorPairIterator>
+ ::value_type*, Comparator, _DifferenceTp>,
+ static_cast<difference_type>(length), comp, tag.get_num_threads());
else
return sequential_multiway_merge
+ </* stable = */ true, /* sentinels = */ true>(
+ seqs_begin, seqs_end, target, *(seqs_begin->second), length, comp);
+}
+
+// public interface
+template<
+ typename RandomAccessIteratorPairIterator
+ , typename RandomAccessIteratorOut
+ , typename _DifferenceTp
+ , typename Comparator>
+RandomAccessIteratorOut
+stable_multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
+ , RandomAccessIteratorPairIterator seqs_end
+ , RandomAccessIteratorOut target
+ , _DifferenceTp length, Comparator comp
+ , sampling_tag tag)
+{
+ typedef _DifferenceTp difference_type;
+ _GLIBCXX_CALL(seqs_end - seqs_begin)
+
+ // catch special case: no sequences
+ if (seqs_begin == seqs_end)
+ return target;
+
+ // Execute merge; maybe parallel, depending on the number of merged
+ // elements and the number of sequences and global thresholds in
+ // Settings.
+ if ((seqs_end - seqs_begin > 1) &&
+ _GLIBCXX_PARALLEL_CONDITION(
+ ((seqs_end - seqs_begin) >=
+ __gnu_parallel::_Settings::get().multiway_merge_minimal_k)
+ && ((sequence_index_t)length >=
+ __gnu_parallel::_Settings::get().multiway_merge_minimal_n)))
+ return parallel_multiway_merge
</* stable = */ true, /* sentinels = */ true>(
seqs_begin, seqs_end,
- target, *(seqs_begin->second), comp, length);
+ target,
+ multiway_merge_sampling_splitting</* stable = */ true,
+ typename std::iterator_traits<RandomAccessIteratorPairIterator>
+ ::value_type*, Comparator, _DifferenceTp>,
+ static_cast<difference_type>(length), comp, tag.get_num_threads());
+ else
+ return sequential_multiway_merge
+ </* stable = */ true, /* sentinels = */ true>(
+ seqs_begin, seqs_end,
+ target, *(seqs_begin->second), length, comp);
+}
+
+// public interface
+template<
+ typename RandomAccessIteratorPairIterator
+ , typename RandomAccessIteratorOut
+ , typename _DifferenceTp
+ , typename Comparator>
+RandomAccessIteratorOut
+stable_multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
+ , RandomAccessIteratorPairIterator seqs_end
+ , RandomAccessIteratorOut target
+ , _DifferenceTp length, Comparator comp
+ , parallel_tag tag = parallel_tag(0))
+{
+ return stable_multiway_merge_sentinels(seqs_begin, seqs_end, target, length, comp,
+ exact_tag(tag.get_num_threads()));
+}
+
+// public interface
+template<
+ typename RandomAccessIteratorPairIterator
+ , typename RandomAccessIteratorOut
+ , typename _DifferenceTp
+ , typename Comparator>
+RandomAccessIteratorOut
+stable_multiway_merge_sentinels(RandomAccessIteratorPairIterator seqs_begin
+ , RandomAccessIteratorPairIterator seqs_end
+ , RandomAccessIteratorOut target
+ , _DifferenceTp length, Comparator comp
+ , default_parallel_tag tag)
+{
+ return stable_multiway_merge_sentinels(seqs_begin, seqs_end, target, length, comp,
+ exact_tag(tag.get_num_threads()));
}
}; // namespace __gnu_parallel
diff --git a/libstdc++-v3/include/parallel/multiway_mergesort.h b/libstdc++-v3/include/parallel/multiway_mergesort.h
index 3791a144d53a088895204dd4e20494a3a775b729..9d9733ad05f5f7c3c8bc41492ab5575f5cdadd3b 100644
--- a/libstdc++-v3/include/parallel/multiway_mergesort.h
+++ b/libstdc++-v3/include/parallel/multiway_mergesort.h
@@ -289,8 +289,8 @@ template<typename SeqRandomAccessIterator, typename RandomAccessIterator,
Comparator& comp,
DiffType length_am) const
{
- stable_multiway_merge(seqs_begin, seqs_end, target, comp,
- length_am, sequential_tag());
+ stable_multiway_merge(seqs_begin, seqs_end, target, length_am, comp,
+ sequential_tag());
}
};
@@ -306,8 +306,8 @@ template<typename SeqRandomAccessIterator, typename RandomAccessIterator,
Comparator& comp,
DiffType length_am) const
{
- multiway_merge(seqs_begin, seqs_end, target, comp,
- length_am, sequential_tag());
+ multiway_merge(seqs_begin, seqs_end, target, length_am, comp,
+ sequential_tag());
}
};
diff --git a/libstdc++-v3/include/parallel/tags.h b/libstdc++-v3/include/parallel/tags.h
index cf937af49525c6258355a3b7fe92a278a3293153..0ca0994e3abce13fdfa30e0daaa6e029bad318a5 100644
--- a/libstdc++-v3/include/parallel/tags.h
+++ b/libstdc++-v3/include/parallel/tags.h
@@ -47,9 +47,6 @@ namespace __gnu_parallel
/** @brief Forces sequential execution at compile time. */
struct sequential_tag { };
- /** @brief Forces exact splitting in multiway merge at compile time. */
- struct exact_tag { };
-
/** @brief Recommends parallel execution at compile time,
* optionally using a user-specified number of threads. */
struct parallel_tag
@@ -119,6 +116,25 @@ namespace __gnu_parallel
struct find_tag { };
+ /** @brief Forces parallel merging
+ * with exact splitting, at compile time. */
+ struct exact_tag : public parallel_tag
+ {
+ exact_tag() { }
+ exact_tag(thread_index_t num_threads)
+ : parallel_tag(num_threads) { }
+ };
+
+ /** @brief Forces parallel merging
+ * with exact splitting, at compile time. */
+ struct sampling_tag : public parallel_tag
+ {
+ sampling_tag() { }
+ sampling_tag(thread_index_t num_threads)
+ : parallel_tag(num_threads) { }
+ };
+
+
/** @brief Forces parallel sorting using multiway mergesort
* at compile time. */
struct multiway_mergesort_tag : public parallel_tag