Provided by: libstdc++-9-doc_9.5.0-3ubuntu1_all 
NAME
__gnu_parallel - GNU parallel code for public use.
SYNOPSIS
Classes
struct __accumulate_binop_reduct
General reduction, using a binary operator.
struct __accumulate_selector
std::accumulate() selector.
struct __adjacent_difference_selector
Selector that returns the difference between two adjacent __elements.
struct __adjacent_find_selector
Test predicate on two adjacent elements.
class __binder1st
Similar to std::binder1st, but giving the argument types explicitly.
class __binder2nd
Similar to std::binder2nd, but giving the argument types explicitly.
struct __count_if_selector
std::count_if () selector.
struct __count_selector
std::count() selector.
struct __fill_selector
std::fill() selector.
struct __find_first_of_selector
Test predicate on several elements.
struct __find_if_selector
Test predicate on a single element, used for std::find() and std::find_if ().
struct __for_each_selector
std::for_each() selector.
struct __generate_selector
std::generate() selector.
struct __generic_find_selector
Base class of all __gnu_parallel::__find_template selectors.
struct __generic_for_each_selector
Generic __selector for embarrassingly parallel functions.
struct __identity_selector
Selector that just returns the passed iterator.
struct __inner_product_selector
std::inner_product() selector.
struct __max_element_reduct
Reduction for finding the maximum element, using a comparator.
struct __min_element_reduct
Reduction for finding the maximum element, using a comparator.
struct __mismatch_selector
Test inverted predicate on a single element.
struct __multiway_merge_3_variant_sentinel_switch
Switch for 3-way merging with __sentinels turned off.
struct __multiway_merge_3_variant_sentinel_switch< true, _RAIterIterator, _RAIter3,
_DifferenceTp, _Compare >
Switch for 3-way merging with __sentinels turned on.
struct __multiway_merge_4_variant_sentinel_switch
Switch for 4-way merging with __sentinels turned off.
struct __multiway_merge_4_variant_sentinel_switch< true, _RAIterIterator, _RAIter3,
_DifferenceTp, _Compare >
Switch for 4-way merging with __sentinels turned on.
struct __multiway_merge_k_variant_sentinel_switch
Switch for k-way merging with __sentinels turned on.
struct __multiway_merge_k_variant_sentinel_switch< false, __stable, _RAIterIterator,
_RAIter3, _DifferenceTp, _Compare >
Switch for k-way merging with __sentinels turned off.
struct __replace_if_selector
std::replace() selector.
struct __replace_selector
std::replace() selector.
struct __transform1_selector
std::transform() __selector, one input sequence variant.
struct __transform2_selector
std::transform() __selector, two input sequences variant.
class __unary_negate
Similar to std::unary_negate, but giving the argument types explicitly.
struct _DRandomShufflingGlobalData
Data known to every thread participating in
__gnu_parallel::__parallel_random_shuffle().
struct _DRSSorterPU
Local data for a thread participating in __gnu_parallel::__parallel_random_shuffle().
struct _DummyReduct
Reduction function doing nothing.
class _EqualFromLess
Constructs predicate for equality from strict weak ordering predicate.
struct _EqualTo
Similar to std::equal_to, but allows two different types.
class _GuardedIterator
_Iterator wrapper supporting an implicit supremum at the end of the sequence,
dominating all comparisons.
class _IteratorPair
A pair of iterators. The usual iterator operations are applied to both child
iterators.
class _IteratorTriple
A triple of iterators. The usual iterator operations are applied to all three child
iterators.
struct _Job
One __job for a certain thread.
struct _Less
Similar to std::less, but allows two different types.
class _Lexicographic
Compare __a pair of types lexicographically, ascending.
class _LexicographicReverse
Compare __a pair of types lexicographically, descending.
class _LoserTree
Stable _LoserTree variant.
class _LoserTree< false, _Tp, _Compare >
Unstable _LoserTree variant.
class _LoserTreeBase
Guarded loser/tournament tree.
class _LoserTreePointer
Stable _LoserTree implementation.
class _LoserTreePointer< false, _Tp, _Compare >
Unstable _LoserTree implementation.
class _LoserTreePointerBase
Base class of _Loser Tree implementation using pointers.
class _LoserTreePointerUnguarded
Stable unguarded _LoserTree variant storing pointers.
class _LoserTreePointerUnguarded< false, _Tp, _Compare >
Unstable unguarded _LoserTree variant storing pointers.
class _LoserTreePointerUnguardedBase
Unguarded loser tree, keeping only pointers to the elements in the tree structure.
struct _LoserTreeTraits
Traits for determining whether the loser tree should use pointers or copies.
class _LoserTreeUnguarded
Stable implementation of unguarded _LoserTree.
class _LoserTreeUnguarded< false, _Tp, _Compare >
Non-Stable implementation of unguarded _LoserTree.
class _LoserTreeUnguardedBase
Base class for unguarded _LoserTree implementation.
struct _Multiplies
Similar to std::multiplies, but allows two different types.
struct _Nothing
Functor doing nothing.
struct _Piece
Subsequence description.
struct _Plus
Similar to std::plus, but allows two different types.
struct _PMWMSSortingData
Data accessed by all threads.
class _PseudoSequence
Sequence that conceptually consists of multiple copies of the same element. The copies
are not stored explicitly, of course.
class _PseudoSequenceIterator
_Iterator associated with __gnu_parallel::_PseudoSequence. If features the usual
random-access iterator functionality.
struct _QSBThreadLocal
Information local to one thread in the parallel quicksort run.
class _RandomNumber
Random number generator, based on the Mersenne twister.
class _RestrictedBoundedConcurrentQueue
Double-ended queue of bounded size, allowing lock-free atomic access. push_front() and
pop_front() must not be called concurrently to each other, while pop_back() can be
called concurrently at all times. empty(), size(), and top() are intentionally not
provided. Calling them would not make sense in a concurrent setting.
struct _SamplingSorter
Stable sorting functor.
struct _SamplingSorter< false, _RAIter, _StrictWeakOrdering >
Non-__stable sorting functor.
struct _Settings
class _Settings Run-time settings for the parallel mode including all tunable
parameters.
struct _SplitConsistently
Split consistently.
struct _SplitConsistently< false, _RAIter, _Compare, _SortingPlacesIterator >
Split by sampling.
struct _SplitConsistently< true, _RAIter, _Compare, _SortingPlacesIterator >
Split by exact splitting.
struct balanced_quicksort_tag
Forces parallel sorting using balanced quicksort at compile time.
struct balanced_tag
Recommends parallel execution using dynamic load-balancing at compile time.
struct constant_size_blocks_tag
Selects the constant block size variant for std::find().
struct default_parallel_tag
Recommends parallel execution using the default parallel algorithm.
struct equal_split_tag
Selects the equal splitting variant for std::find().
struct exact_tag
Forces parallel merging with exact splitting, at compile time.
struct find_tag
Base class for for std::find() variants.
struct growing_blocks_tag
Selects the growing block size variant for std::find().
struct multiway_mergesort_exact_tag
Forces parallel sorting using multiway mergesort with exact splitting at compile time.
struct multiway_mergesort_sampling_tag
Forces parallel sorting using multiway mergesort with splitting by sampling at compile
time.
struct multiway_mergesort_tag
Forces parallel sorting using multiway mergesort at compile time.
struct omp_loop_static_tag
Recommends parallel execution using OpenMP static load-balancing at compile time.
struct omp_loop_tag
Recommends parallel execution using OpenMP dynamic load-balancing at compile time.
struct parallel_tag
Recommends parallel execution at compile time, optionally using a user-specified
number of threads.
struct quicksort_tag
Forces parallel sorting using unbalanced quicksort at compile time.
struct sampling_tag
Forces parallel merging with exact splitting, at compile time.
struct sequential_tag
Forces sequential execution at compile time.
struct unbalanced_tag
Recommends parallel execution using static load-balancing at compile time.
Typedefs
typedef unsigned short _BinIndex
Type to hold the index of a bin.
typedef int64_t _CASable
Longest compare-and-swappable integer type on this platform.
typedef uint64_t _SequenceIndex
Unsigned integer to index __elements. The total number of elements for each algorithm
must fit into this type.
typedef uint16_t _ThreadIndex
Unsigned integer to index a thread number. The maximum thread number (for each
processor) must fit into this type.
Enumerations
enum _AlgorithmStrategy { heuristic, force_sequential, force_parallel }
Strategies for run-time algorithm selection:
enum _FindAlgorithm { GROWING_BLOCKS, CONSTANT_SIZE_BLOCKS, EQUAL_SPLIT }
Find algorithms:
enum _MultiwayMergeAlgorithm { LOSER_TREE }
Merging algorithms:
enum _Parallelism { sequential, parallel_unbalanced, parallel_balanced, parallel_omp_loop,
parallel_omp_loop_static, parallel_taskqueue }
Run-time equivalents for the compile-time tags.
enum _PartialSumAlgorithm { RECURSIVE, LINEAR }
Partial sum algorithms: recursive, linear.
enum _SortAlgorithm { MWMS, QS, QS_BALANCED }
Sorting algorithms:
enum _SplittingAlgorithm { SAMPLING, EXACT }
Sorting/merging algorithms: sampling, __exact.
Functions
template<typename _Tp > _Tp __add_omp (volatile _Tp *__ptr, _Tp __addend)
template<typename _RAIter , typename _DifferenceTp > void __calc_borders (_RAIter
__elements, _DifferenceTp __length, _DifferenceTp *__off)
Precalculate __advances for Knuth-Morris-Pratt algorithm.
template<typename _Tp > bool __cas_omp (volatile _Tp *__ptr, _Tp __comparand, _Tp
__replacement)
template<typename _Tp > bool __compare_and_swap (volatile _Tp *__ptr, _Tp __comparand, _Tp
__replacement)
Compare-and-swap.
template<typename _IIter , typename _OutputIterator > _OutputIterator __copy_tail
(std::pair< _IIter, _IIter > __b, std::pair< _IIter, _IIter > __e, _OutputIterator
__r)
void __decode2 (_CASable __x, int &__a, int &__b)
Decode two integers from one gnu_parallel::_CASable.
template<typename _RAIter , typename _DifferenceTp > void __determine_samples
(_PMWMSSortingData< _RAIter > *__sd, _DifferenceTp __num_samples)
Select _M_samples from a sequence.
_CASable __encode2 (int __a, int __b)
Encode two integers into one gnu_parallel::_CASable.
template<typename _DifferenceType , typename _OutputIterator > _OutputIterator
__equally_split (_DifferenceType __n, _ThreadIndex __num_threads, _OutputIterator __s)
function to split a sequence into parts of almost equal size.
template<typename _DifferenceType > _DifferenceType __equally_split_point (_DifferenceType
__n, _ThreadIndex __num_threads, _ThreadIndex __thread_no)
function to split a sequence into parts of almost equal size.
template<typename _Tp > _Tp __fetch_and_add (volatile _Tp *__ptr, _Tp __addend)
Add a value to a variable, atomically.
template<typename _RAIter1 , typename _RAIter2 , typename _Pred , typename _Selector >
std::pair< _RAIter1, _RAIter2 > __find_template (_RAIter1 __begin1, _RAIter1 __end1,
_RAIter2 __begin2, _Pred __pred, _Selector __selector)
Parallel std::find, switch for different algorithms.
template<typename _RAIter1 , typename _RAIter2 , typename _Pred , typename _Selector >
std::pair< _RAIter1, _RAIter2 > __find_template (_RAIter1 __begin1, _RAIter1 __end1,
_RAIter2 __begin2, _Pred __pred, _Selector __selector, constant_size_blocks_tag)
Parallel std::find, constant block size variant.
template<typename _RAIter1 , typename _RAIter2 , typename _Pred , typename _Selector >
std::pair< _RAIter1, _RAIter2 > __find_template (_RAIter1 __begin1, _RAIter1 __end1,
_RAIter2 __begin2, _Pred __pred, _Selector __selector, equal_split_tag)
Parallel std::find, equal splitting variant.
template<typename _RAIter1 , typename _RAIter2 , typename _Pred , typename _Selector >
std::pair< _RAIter1, _RAIter2 > __find_template (_RAIter1 __begin1, _RAIter1 __end1,
_RAIter2 __begin2, _Pred __pred, _Selector __selector, growing_blocks_tag)
Parallel std::find, growing block size variant.
template<typename _IIter , typename _UserOp , typename _Functionality , typename _Red ,
typename _Result > _UserOp __for_each_template_random_access (_IIter __begin, _IIter
__end, _UserOp __user_op, _Functionality &__functionality, _Red __reduction, _Result
__reduction_start, _Result &__output, typename std::iterator_traits< _IIter
>::difference_type __bound, _Parallelism __parallelism_tag)
Chose the desired algorithm by evaluating __parallelism_tag.
template<typename _RAIter , typename _Op , typename _Fu , typename _Red , typename _Result
> _Op __for_each_template_random_access_ed (_RAIter __begin, _RAIter __end, _Op __o,
_Fu &__f, _Red __r, _Result __base, _Result &__output, typename std::iterator_traits<
_RAIter >::difference_type __bound)
Embarrassingly parallel algorithm for random access iterators, using hand-crafted
parallelization by equal splitting the work.
template<typename _RAIter , typename _Op , typename _Fu , typename _Red , typename _Result
> _Op __for_each_template_random_access_omp_loop (_RAIter __begin, _RAIter __end, _Op
__o, _Fu &__f, _Red __r, _Result __base, _Result &__output, typename
std::iterator_traits< _RAIter >::difference_type __bound)
Embarrassingly parallel algorithm for random access iterators, using an OpenMP for
loop.
template<typename _RAIter , typename _Op , typename _Fu , typename _Red , typename _Result
> _Op __for_each_template_random_access_omp_loop_static (_RAIter __begin, _RAIter
__end, _Op __o, _Fu &__f, _Red __r, _Result __base, _Result &__output, typename
std::iterator_traits< _RAIter >::difference_type __bound)
Embarrassingly parallel algorithm for random access iterators, using an OpenMP for
loop with static scheduling.
template<typename _RAIter , typename _Op , typename _Fu , typename _Red , typename _Result
> _Op __for_each_template_random_access_workstealing (_RAIter __begin, _RAIter __end,
_Op __op, _Fu &__f, _Red __r, _Result __base, _Result &__output, typename
std::iterator_traits< _RAIter >::difference_type __bound)
Work stealing algorithm for random access iterators.
_ThreadIndex __get_max_threads ()
bool __is_parallel (const _Parallelism __p)
template<typename _IIter , typename _Compare > bool __is_sorted (_IIter __begin, _IIter
__end, _Compare __comp)
Check whether [__begin, __end) is sorted according to __comp.
template<typename _RAIter , typename _Compare > _RAIter __median_of_three_iterators
(_RAIter __a, _RAIter __b, _RAIter __c, _Compare __comp)
Compute the median of three referenced elements, according to __comp.
template<typename _RAIter1 , typename _RAIter2 , typename _OutputIterator , typename
_DifferenceTp , typename _Compare > _OutputIterator __merge_advance (_RAIter1
&__begin1, _RAIter1 __end1, _RAIter2 &__begin2, _RAIter2 __end2, _OutputIterator
__target, _DifferenceTp __max_length, _Compare __comp)
Merge routine being able to merge only the __max_length smallest elements.
template<typename _RAIter1 , typename _RAIter2 , typename _OutputIterator , typename
_DifferenceTp , typename _Compare > _OutputIterator __merge_advance_movc (_RAIter1
&__begin1, _RAIter1 __end1, _RAIter2 &__begin2, _RAIter2 __end2, _OutputIterator
__target, _DifferenceTp __max_length, _Compare __comp)
Merge routine being able to merge only the __max_length smallest elements.
template<typename _RAIter1 , typename _RAIter2 , typename _OutputIterator , typename
_DifferenceTp , typename _Compare > _OutputIterator __merge_advance_usual (_RAIter1
&__begin1, _RAIter1 __end1, _RAIter2 &__begin2, _RAIter2 __end2, _OutputIterator
__target, _DifferenceTp __max_length, _Compare __comp)
Merge routine being able to merge only the __max_length smallest elements.
template<typename _RAIter1 , typename _RAIter3 , typename _Compare > _RAIter3
__parallel_merge_advance (_RAIter1 &__begin1, _RAIter1 __end1, _RAIter1 &__begin2,
_RAIter1 __end2, _RAIter3 __target, typename std::iterator_traits< _RAIter1
>::difference_type __max_length, _Compare __comp)
Parallel merge routine being able to merge only the __max_length smallest elements.
template<typename _RAIter1 , typename _RAIter2 , typename _RAIter3 , typename _Compare >
_RAIter3 __parallel_merge_advance (_RAIter1 &__begin1, _RAIter1 __end1, _RAIter2
&__begin2, _RAIter2 __end2, _RAIter3 __target, typename std::iterator_traits< _RAIter1
>::difference_type __max_length, _Compare __comp)
Merge routine fallback to sequential in case the iterators of the two input sequences
are of different type.
template<typename _RAIter , typename _Compare > void __parallel_nth_element (_RAIter
__begin, _RAIter __nth, _RAIter __end, _Compare __comp)
Parallel implementation of std::nth_element().
template<typename _RAIter , typename _Compare > void __parallel_partial_sort (_RAIter
__begin, _RAIter __middle, _RAIter __end, _Compare __comp)
Parallel implementation of std::partial_sort().
template<typename _IIter , typename _OutputIterator , typename _BinaryOperation >
_OutputIterator __parallel_partial_sum (_IIter __begin, _IIter __end, _OutputIterator
__result, _BinaryOperation __bin_op)
Parallel partial sum front-__end.
template<typename _IIter , typename _OutputIterator , typename _BinaryOperation >
_OutputIterator __parallel_partial_sum_basecase (_IIter __begin, _IIter __end,
_OutputIterator __result, _BinaryOperation __bin_op, typename std::iterator_traits<
_IIter >::value_type __value)
Base case prefix sum routine.
template<typename _IIter , typename _OutputIterator , typename _BinaryOperation >
_OutputIterator __parallel_partial_sum_linear (_IIter __begin, _IIter __end,
_OutputIterator __result, _BinaryOperation __bin_op, typename std::iterator_traits<
_IIter >::difference_type __n)
Parallel partial sum implementation, two-phase approach, no recursion.
template<typename _RAIter , typename _Predicate > std::iterator_traits< _RAIter
>::difference_type __parallel_partition (_RAIter __begin, _RAIter __end, _Predicate
__pred, _ThreadIndex __num_threads)
Parallel implementation of std::partition.
template<typename _RAIter , typename _RandomNumberGenerator > void
__parallel_random_shuffle (_RAIter __begin, _RAIter __end, _RandomNumberGenerator
__rng=_RandomNumber())
Parallel random public call.
template<typename _RAIter , typename _RandomNumberGenerator > void
__parallel_random_shuffle_drs (_RAIter __begin, _RAIter __end, typename
std::iterator_traits< _RAIter >::difference_type __n, _ThreadIndex __num_threads,
_RandomNumberGenerator &__rng)
Main parallel random shuffle step.
template<typename _RAIter , typename _RandomNumberGenerator > void
__parallel_random_shuffle_drs_pu (_DRSSorterPU< _RAIter, _RandomNumberGenerator >
*__pus)
Random shuffle code executed by each thread.
template<typename _IIter , typename _OutputIterator , typename _Compare > _OutputIterator
__parallel_set_difference (_IIter __begin1, _IIter __end1, _IIter __begin2, _IIter
__end2, _OutputIterator __result, _Compare __comp)
template<typename _IIter , typename _OutputIterator , typename _Compare > _OutputIterator
__parallel_set_intersection (_IIter __begin1, _IIter __end1, _IIter __begin2, _IIter
__end2, _OutputIterator __result, _Compare __comp)
template<typename _IIter , typename _OutputIterator , typename _Operation >
_OutputIterator __parallel_set_operation (_IIter __begin1, _IIter __end1, _IIter
__begin2, _IIter __end2, _OutputIterator __result, _Operation __op)
template<typename _IIter , typename _OutputIterator , typename _Compare > _OutputIterator
__parallel_set_symmetric_difference (_IIter __begin1, _IIter __end1, _IIter __begin2,
_IIter __end2, _OutputIterator __result, _Compare __comp)
template<typename _IIter , typename _OutputIterator , typename _Compare > _OutputIterator
__parallel_set_union (_IIter __begin1, _IIter __end1, _IIter __begin2, _IIter __end2,
_OutputIterator __result, _Compare __comp)
template<bool __stable, typename _RAIter , typename _Compare , typename _Parallelism >
void __parallel_sort (_RAIter __begin, _RAIter __end, _Compare __comp, _Parallelism
__parallelism)
template<bool __stable, typename _RAIter , typename _Compare > void __parallel_sort
(_RAIter __begin, _RAIter __end, _Compare __comp, balanced_quicksort_tag
__parallelism)
Choose balanced quicksort for parallel sorting.
template<bool __stable, typename _RAIter , typename _Compare > void __parallel_sort
(_RAIter __begin, _RAIter __end, _Compare __comp, default_parallel_tag __parallelism)
Choose multiway mergesort with exact splitting, for parallel sorting.
template<bool __stable, typename _RAIter , typename _Compare > void __parallel_sort
(_RAIter __begin, _RAIter __end, _Compare __comp, multiway_mergesort_exact_tag
__parallelism)
Choose multiway mergesort with exact splitting, for parallel sorting.
template<bool __stable, typename _RAIter , typename _Compare > void __parallel_sort
(_RAIter __begin, _RAIter __end, _Compare __comp, multiway_mergesort_sampling_tag
__parallelism)
Choose multiway mergesort with splitting by sampling, for parallel sorting.
template<bool __stable, typename _RAIter , typename _Compare > void __parallel_sort
(_RAIter __begin, _RAIter __end, _Compare __comp, multiway_mergesort_tag
__parallelism)
Choose multiway mergesort, splitting variant at run-time, for parallel sorting.
template<bool __stable, typename _RAIter , typename _Compare > void __parallel_sort
(_RAIter __begin, _RAIter __end, _Compare __comp, parallel_tag __parallelism)
Choose a parallel sorting algorithm.
template<bool __stable, typename _RAIter , typename _Compare > void __parallel_sort
(_RAIter __begin, _RAIter __end, _Compare __comp, quicksort_tag __parallelism)
Choose quicksort for parallel sorting.
template<typename _RAIter , typename _Compare > void __parallel_sort_qs (_RAIter __begin,
_RAIter __end, _Compare __comp, _ThreadIndex __num_threads)
Unbalanced quicksort main call.
template<typename _RAIter , typename _Compare > void __parallel_sort_qs_conquer (_RAIter
__begin, _RAIter __end, _Compare __comp, _ThreadIndex __num_threads)
Unbalanced quicksort conquer step.
template<typename _RAIter , typename _Compare > std::iterator_traits< _RAIter
>::difference_type __parallel_sort_qs_divide (_RAIter __begin, _RAIter __end, _Compare
__comp, typename std::iterator_traits< _RAIter >::difference_type __pivot_rank,
typename std::iterator_traits< _RAIter >::difference_type __num_samples, _ThreadIndex
__num_threads)
Unbalanced quicksort divide step.
template<typename _RAIter , typename _Compare > void __parallel_sort_qsb (_RAIter __begin,
_RAIter __end, _Compare __comp, _ThreadIndex __num_threads)
Top-level quicksort routine.
template<typename _IIter , class _OutputIterator > _OutputIterator __parallel_unique_copy
(_IIter __first, _IIter __last, _OutputIterator __result)
Parallel std::unique_copy(), without explicit equality predicate.
template<typename _IIter , class _OutputIterator , class _BinaryPredicate >
_OutputIterator __parallel_unique_copy (_IIter __first, _IIter __last, _OutputIterator
__result, _BinaryPredicate __binary_pred)
Parallel std::unique_copy(), w/__o explicit equality predicate.
template<typename _RAIter , typename _Compare > void __qsb_conquer (_QSBThreadLocal<
_RAIter > **__tls, _RAIter __begin, _RAIter __end, _Compare __comp, _ThreadIndex
__iam, _ThreadIndex __num_threads, bool __parent_wait)
Quicksort conquer step.
template<typename _RAIter , typename _Compare > std::iterator_traits< _RAIter
>::difference_type __qsb_divide (_RAIter __begin, _RAIter __end, _Compare __comp,
_ThreadIndex __num_threads)
Balanced quicksort divide step.
template<typename _RAIter , typename _Compare > void __qsb_local_sort_with_helping
(_QSBThreadLocal< _RAIter > **__tls, _Compare &__comp, _ThreadIndex __iam, bool
__wait)
Quicksort step doing load-balanced local sort.
template<typename _RandomNumberGenerator > int __random_number_pow2 (int __logp,
_RandomNumberGenerator &__rng)
Generate a random number in [0,2^__logp).
template<typename _Size > _Size __rd_log2 (_Size __n)
Calculates the rounded-down logarithm of __n for base 2.
template<typename _Tp > _Tp __round_up_to_pow2 (_Tp __x)
Round up to the next greater power of 2.
template<typename __RAIter1 , typename __RAIter2 , typename _Pred > __RAIter1
__search_template (__RAIter1 __begin1, __RAIter1 __end1, __RAIter2 __begin2, __RAIter2
__end2, _Pred __pred)
Parallel std::search.
template<bool __stable, bool __sentinels, typename _RAIterIterator , typename _RAIter3 ,
typename _DifferenceTp , typename _Compare > _RAIter3 __sequential_multiway_merge
(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, const
typename std::iterator_traits< typename std::iterator_traits< _RAIterIterator
>::value_type::first_type >::value_type &__sentinel, _DifferenceTp __length, _Compare
__comp)
Sequential multi-way merging switch.
template<typename _RAIter , typename _RandomNumberGenerator > void
__sequential_random_shuffle (_RAIter __begin, _RAIter __end, _RandomNumberGenerator
&__rng)
Sequential cache-efficient random shuffle.
template<typename _IIter > void __shrink (std::vector< _IIter > &__os_starts, size_t
&__count_to_two, size_t &__range_length)
Combines two ranges into one and thus halves the number of ranges.
template<typename _IIter > void __shrink_and_double (std::vector< _IIter > &__os_starts,
size_t &__count_to_two, size_t &__range_length, const bool __make_twice)
Shrinks and doubles the ranges.
void __yield ()
Yield control to another thread, without waiting for the end of the time slice.
template<typename _IIter , typename _FunctorType > size_t list_partition (const _IIter
__begin, const _IIter __end, _IIter *__starts, size_t *__lengths, const int
__num_parts, _FunctorType &__f, int __oversampling=0)
Splits a sequence given by input iterators into parts of almost equal size.
template<typename _Tp > const _Tp & max (const _Tp &__a, const _Tp &__b)
Equivalent to std::max.
template<typename _Tp > const _Tp & min (const _Tp &__a, const _Tp &__b)
Equivalent to std::min.
template<typename _RanSeqs , typename _RankType , typename _RankIterator , typename
_Compare > void multiseq_partition (_RanSeqs __begin_seqs, _RanSeqs __end_seqs,
_RankType __rank, _RankIterator __begin_offsets, _Compare __comp=std::less< typename
std::iterator_traits< typename std::iterator_traits< _RanSeqs
>::value_type::first_type >::value_type >())
Splits several sorted sequences at a certain global __rank, resulting in a splitting
point for each sequence. The sequences are passed via a sequence of random-access
iterator pairs, none of the sequences may be empty. If there are several equal
elements across the split, the ones on the __left side will be chosen from sequences
with smaller number.
template<typename _Tp , typename _RanSeqs , typename _RankType , typename _Compare > _Tp
multiseq_selection (_RanSeqs __begin_seqs, _RanSeqs __end_seqs, _RankType __rank,
_RankType &__offset, _Compare __comp=std::less< _Tp >())
Selects the element at a certain global __rank from several sorted sequences.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut multiway_merge (_RAIterPairIterator __seqs_begin,
_RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare
__comp, __gnu_parallel::exact_tag __tag)
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut multiway_merge (_RAIterPairIterator __seqs_begin,
_RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare
__comp, __gnu_parallel::sampling_tag __tag)
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut multiway_merge (_RAIterPairIterator __seqs_begin,
_RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare
__comp, __gnu_parallel::sequential_tag)
Multiway Merge Frontend.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut multiway_merge (_RAIterPairIterator __seqs_begin,
_RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare
__comp, default_parallel_tag __tag)
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut multiway_merge (_RAIterPairIterator __seqs_begin,
_RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length, _Compare
__comp, parallel_tag __tag=parallel_tag(0))
template<template< typename RAI, typename C > class iterator, typename _RAIterIterator ,
typename _RAIter3 , typename _DifferenceTp , typename _Compare > _RAIter3
multiway_merge_3_variant (_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end,
_RAIter3 __target, _DifferenceTp __length, _Compare __comp)
Highly efficient 3-way merging procedure.
template<template< typename RAI, typename C > class iterator, typename _RAIterIterator ,
typename _RAIter3 , typename _DifferenceTp , typename _Compare > _RAIter3
multiway_merge_4_variant (_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end,
_RAIter3 __target, _DifferenceTp __length, _Compare __comp)
Highly efficient 4-way merging procedure.
template<bool __stable, typename _RAIterIterator , typename _Compare , typename
_DifferenceType > void multiway_merge_exact_splitting (_RAIterIterator __seqs_begin,
_RAIterIterator __seqs_end, _DifferenceType __length, _DifferenceType __total_length,
_Compare __comp, std::vector< std::pair< _DifferenceType, _DifferenceType > >
*__pieces)
Exact splitting for parallel multiway-merge routine.
template<typename _LT , typename _RAIterIterator , typename _RAIter3 , typename
_DifferenceTp , typename _Compare > _RAIter3 multiway_merge_loser_tree
(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target,
_DifferenceTp __length, _Compare __comp)
Multi-way merging procedure for a high branching factor, guarded case.
template<typename UnguardedLoserTree , typename _RAIterIterator , typename _RAIter3 ,
typename _DifferenceTp , typename _Compare > _RAIter3
multiway_merge_loser_tree_sentinel (_RAIterIterator __seqs_begin, _RAIterIterator
__seqs_end, _RAIter3 __target, const typename std::iterator_traits< typename
std::iterator_traits< _RAIterIterator >::value_type::first_type >::value_type
&__sentinel, _DifferenceTp __length, _Compare __comp)
Multi-way merging procedure for a high branching factor, requiring sentinels to exist.
template<typename _LT , typename _RAIterIterator , typename _RAIter3 , typename
_DifferenceTp , typename _Compare > _RAIter3 multiway_merge_loser_tree_unguarded
(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, const
typename std::iterator_traits< typename std::iterator_traits< _RAIterIterator
>::value_type::first_type >::value_type &__sentinel, _DifferenceTp __length, _Compare
__comp)
Multi-way merging procedure for a high branching factor, unguarded case.
template<bool __stable, typename _RAIterIterator , typename _Compare , typename
_DifferenceType > void multiway_merge_sampling_splitting (_RAIterIterator
__seqs_begin, _RAIterIterator __seqs_end, _DifferenceType __length, _DifferenceType
__total_length, _Compare __comp, std::vector< std::pair< _DifferenceType,
_DifferenceType > > *__pieces)
Sampling based splitting for parallel multiway-merge routine.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut multiway_merge_sentinels (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, __gnu_parallel::exact_tag __tag)
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut multiway_merge_sentinels (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, __gnu_parallel::sequential_tag)
Multiway Merge Frontend.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut multiway_merge_sentinels (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, default_parallel_tag __tag)
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut multiway_merge_sentinels (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, parallel_tag __tag=parallel_tag(0))
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut multiway_merge_sentinels (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, sampling_tag __tag)
template<bool __stable, bool __sentinels, typename _RAIterIterator , typename _RAIter3 ,
typename _DifferenceTp , typename _Splitter , typename _Compare > _RAIter3
parallel_multiway_merge (_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end,
_RAIter3 __target, _Splitter __splitter, _DifferenceTp __length, _Compare __comp,
_ThreadIndex __num_threads)
Parallel multi-way merge routine.
template<bool __stable, bool __exact, typename _RAIter , typename _Compare > void
parallel_sort_mwms (_RAIter __begin, _RAIter __end, _Compare __comp, _ThreadIndex
__num_threads)
PMWMS main call.
template<bool __stable, bool __exact, typename _RAIter , typename _Compare > void
parallel_sort_mwms_pu (_PMWMSSortingData< _RAIter > *__sd, _Compare &__comp)
PMWMS code executed by each thread.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut stable_multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, __gnu_parallel::exact_tag __tag)
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut stable_multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, __gnu_parallel::sequential_tag)
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut stable_multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, default_parallel_tag __tag)
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut stable_multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, parallel_tag __tag=parallel_tag(0))
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut stable_multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, sampling_tag __tag)
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut stable_multiway_merge_sentinels (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, __gnu_parallel::exact_tag __tag)
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut stable_multiway_merge_sentinels (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, __gnu_parallel::sequential_tag)
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut stable_multiway_merge_sentinels (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, default_parallel_tag __tag)
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut stable_multiway_merge_sentinels (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, parallel_tag __tag=parallel_tag(0))
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut stable_multiway_merge_sentinels (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp
__length, _Compare __comp, sampling_tag __tag)
Variables
static const int _CASable_bits
Number of bits of _CASable.
static const _CASable _CASable_mask
_CASable with the right half of bits set to 1.
Detailed Description
GNU parallel code for public use.
Typedef Documentation
typedef unsigned short __gnu_parallel::_BinIndex
Type to hold the index of a bin. Since many variables of this type are allocated, it
should be chosen as small as possible.
Definition at line 47 of file random_shuffle.h.
typedef int64_t __gnu_parallel::_CASable
Longest compare-and-swappable integer type on this platform.
Definition at line 127 of file types.h.
typedef uint64_t __gnu_parallel::_SequenceIndex
Unsigned integer to index __elements. The total number of elements for each algorithm must
fit into this type.
Definition at line 117 of file types.h.
typedef uint16_t __gnu_parallel::_ThreadIndex
Unsigned integer to index a thread number. The maximum thread number (for each processor)
must fit into this type.
Definition at line 123 of file types.h.
Enumeration Type Documentation
enum __gnu_parallel::_AlgorithmStrategy
Strategies for run-time algorithm selection:
Definition at line 67 of file types.h.
enum __gnu_parallel::_FindAlgorithm
Find algorithms:
Definition at line 106 of file types.h.
enum __gnu_parallel::_MultiwayMergeAlgorithm
Merging algorithms:
Definition at line 85 of file types.h.
enum __gnu_parallel::_Parallelism
Run-time equivalents for the compile-time tags.
Enumerator
sequential
Not parallel.
parallel_unbalanced
Parallel unbalanced (equal-sized chunks).
parallel_balanced
Parallel balanced (work-stealing).
parallel_omp_loop
Parallel with OpenMP dynamic load-balancing.
parallel_omp_loop_static
Parallel with OpenMP static load-balancing.
parallel_taskqueue
Parallel with OpenMP taskqueue construct.
Definition at line 44 of file types.h.
enum __gnu_parallel::_PartialSumAlgorithm
Partial sum algorithms: recursive, linear.
Definition at line 91 of file types.h.
enum __gnu_parallel::_SortAlgorithm
Sorting algorithms:
Definition at line 76 of file types.h.
enum __gnu_parallel::_SplittingAlgorithm
Sorting/merging algorithms: sampling, __exact.
Definition at line 98 of file types.h.
Function Documentation
template<typename _Tp > _Tp __gnu_parallel::__add_omp (volatile _Tp * __ptr, _Tp __addend)
[inline]
Definition at line 56 of file parallel/compatibility.h.
template<typename _RAIter , typename _DifferenceTp > void __gnu_parallel::__calc_borders
(_RAIter __elements, _DifferenceTp __length, _DifferenceTp * __off)
Precalculate __advances for Knuth-Morris-Pratt algorithm.
Parameters
__elements Begin iterator of sequence to search for.
__length Length of sequence to search for.
__off Returned __offsets.
Definition at line 51 of file search.h.
Referenced by __search_template().
template<typename _Tp > bool __gnu_parallel::__cas_omp (volatile _Tp * __ptr, _Tp __comparand,
_Tp __replacement) [inline]
Definition at line 83 of file parallel/compatibility.h.
template<typename _Tp > bool __gnu_parallel::__compare_and_swap (volatile _Tp * __ptr, _Tp
__comparand, _Tp __replacement) [inline]
Compare-and-swap. Compare *__ptr and __comparand. If equal, let *__ptr=__replacement and
return true, return false otherwise.
Parameters
__ptr Pointer to signed integer.
__comparand Compare value.
__replacement Replacement value.
Definition at line 108 of file parallel/compatibility.h.
Referenced by __parallel_partition(), __gnu_parallel::_RestrictedBoundedConcurrentQueue<
_Tp >::pop_back(), and __gnu_parallel::_RestrictedBoundedConcurrentQueue< _Tp
>::pop_front().
template<typename _IIter , typename _OutputIterator > _OutputIterator
__gnu_parallel::__copy_tail (std::pair< _IIter, _IIter > __b, std::pair< _IIter, _IIter >
__e, _OutputIterator __r)
Definition at line 46 of file set_operations.h.
void __gnu_parallel::__decode2 (_CASable __x, int & __a, int & __b) [inline]
Decode two integers from one gnu_parallel::_CASable.
Parameters
__x __gnu_parallel::_CASable to decode integers from.
__a First integer, to be decoded from the most-significant _CASable_bits/2 bits of
__x.
__b Second integer, to be encoded in the least-significant _CASable_bits/2 bits of
__x.
See also
__encode2
Definition at line 133 of file parallel/base.h.
References _CASable_bits, and _CASable_mask.
Referenced by __gnu_parallel::_RestrictedBoundedConcurrentQueue< _Tp >::pop_back(),
__gnu_parallel::_RestrictedBoundedConcurrentQueue< _Tp >::pop_front(), and
__gnu_parallel::_RestrictedBoundedConcurrentQueue< _Tp >::push_front().
template<typename _RAIter , typename _DifferenceTp > void __gnu_parallel::__determine_samples
(_PMWMSSortingData< _RAIter > * __sd, _DifferenceTp __num_samples)
Select _M_samples from a sequence.
Parameters
__sd Pointer to algorithm data. _Result will be placed in __sd->_M_samples.
__num_samples Number of _M_samples to select.
Definition at line 97 of file multiway_mergesort.h.
References __equally_split(), __gnu_parallel::_PMWMSSortingData< _RAIter >::_M_samples,
__gnu_parallel::_PMWMSSortingData< _RAIter >::_M_source, and
__gnu_parallel::_PMWMSSortingData< _RAIter >::_M_starts.
_CASable __gnu_parallel::__encode2 (int __a, int __b) [inline]
Encode two integers into one gnu_parallel::_CASable.
Parameters
__a First integer, to be encoded in the most-significant _CASable_bits/2 bits.
__b Second integer, to be encoded in the least-significant _CASable_bits/2 bits.
Returns
value encoding __a and __b.
See also
__decode2
Definition at line 119 of file parallel/base.h.
References _CASable_bits.
Referenced by __gnu_parallel::_RestrictedBoundedConcurrentQueue< _Tp
>::_RestrictedBoundedConcurrentQueue(), __gnu_parallel::_RestrictedBoundedConcurrentQueue<
_Tp >::pop_back(), and __gnu_parallel::_RestrictedBoundedConcurrentQueue< _Tp
>::pop_front().
template<typename _DifferenceType , typename _OutputIterator > _OutputIterator
__gnu_parallel::__equally_split (_DifferenceType __n, _ThreadIndex __num_threads,
_OutputIterator __s)
function to split a sequence into parts of almost equal size. The resulting sequence __s
of length __num_threads+1 contains the splitting positions when splitting the range
[0,__n) into parts of almost equal size (plus minus 1). The first entry is 0, the last one
n. There may result empty parts.
Parameters
__n Number of elements
__num_threads Number of parts
__s Splitters
Returns
End of __splitter sequence, i.e. __s+__num_threads+1
Definition at line 48 of file equally_split.h.
Referenced by __determine_samples(), __find_template(), __parallel_partial_sum_linear(),
and __search_template().
template<typename _DifferenceType > _DifferenceType __gnu_parallel::__equally_split_point
(_DifferenceType __n, _ThreadIndex __num_threads, _ThreadIndex __thread_no)
function to split a sequence into parts of almost equal size. Returns the position of the
splitting point between thread number __thread_no (included) and thread number
__thread_no+1 (excluded).
Parameters
__n Number of elements
__num_threads Number of parts
__thread_no Number of threads
Returns
splitting point
Definition at line 75 of file equally_split.h.
Referenced by __for_each_template_random_access_ed().
template<typename _Tp > _Tp __gnu_parallel::__fetch_and_add (volatile _Tp * __ptr, _Tp
__addend) [inline]
Add a value to a variable, atomically.
Parameters
__ptr Pointer to a signed integer.
__addend Value to add.
Definition at line 74 of file parallel/compatibility.h.
Referenced by __parallel_partition().
template<typename _RAIter1 , typename _RAIter2 , typename _Pred , typename _Selector >
std::pair< _RAIter1, _RAIter2 > __gnu_parallel::__find_template (_RAIter1 __begin1,
_RAIter1 __end1, _RAIter2 __begin2, _Pred __pred, _Selector __selector) [inline]
Parallel std::find, switch for different algorithms.
Parameters
__begin1 Begin iterator of first sequence.
__end1 End iterator of first sequence.
__begin2 Begin iterator of second sequence. Must have same length as first sequence.
__pred Find predicate.
__selector _Functionality (e. g. std::find_if(), std::equal(),...)
Returns
Place of finding in both sequences.
Definition at line 60 of file find.h.
References __find_template(), and __gnu_parallel::_Settings::get().
Referenced by __find_template().
template<typename _RAIter1 , typename _RAIter2 , typename _Pred , typename _Selector >
std::pair< _RAIter1, _RAIter2 > __gnu_parallel::__find_template (_RAIter1 __begin1,
_RAIter1 __end1, _RAIter2 __begin2, _Pred __pred, _Selector __selector,
constant_size_blocks_tag)
Parallel std::find, constant block size variant.
Parameters
__begin1 Begin iterator of first sequence.
__end1 End iterator of first sequence.
__begin2 Begin iterator of second sequence. Second __sequence must have same length as
first sequence.
__pred Find predicate.
__selector _Functionality (e. g. std::find_if(), std::equal(),...)
Returns
Place of finding in both sequences.
See also
__gnu_parallel::_Settings::find_sequential_search_size
__gnu_parallel::_Settings::find_block_size There are two main differences between the
growing blocks and the constant-size blocks variants. 1. For GB, the block size grows;
for CSB, the block size is fixed. 2. For GB, the blocks are allocated dynamically; for
CSB, the blocks are allocated in a predetermined manner, namely spacial round-robin.
Definition at line 315 of file find.h.
References _GLIBCXX_CALL, __gnu_parallel::_Settings::find_initial_block_size,
__gnu_parallel::_Settings::find_sequential_search_size, std::pair< _T1, _T2 >::first, and
__gnu_parallel::_Settings::get().
template<typename _RAIter1 , typename _RAIter2 , typename _Pred , typename _Selector >
std::pair< _RAIter1, _RAIter2 > __gnu_parallel::__find_template (_RAIter1 __begin1,
_RAIter1 __end1, _RAIter2 __begin2, _Pred __pred, _Selector __selector, equal_split_tag)
Parallel std::find, equal splitting variant.
Parameters
__begin1 Begin iterator of first sequence.
__end1 End iterator of first sequence.
__begin2 Begin iterator of second sequence. Second __sequence must have same length as
first sequence.
__pred Find predicate.
__selector _Functionality (e. g. std::find_if(), std::equal(),...)
Returns
Place of finding in both sequences.
Definition at line 97 of file find.h.
References __equally_split(), and _GLIBCXX_CALL.
template<typename _RAIter1 , typename _RAIter2 , typename _Pred , typename _Selector >
std::pair< _RAIter1, _RAIter2 > __gnu_parallel::__find_template (_RAIter1 __begin1,
_RAIter1 __end1, _RAIter2 __begin2, _Pred __pred, _Selector __selector,
growing_blocks_tag)
Parallel std::find, growing block size variant.
Parameters
__begin1 Begin iterator of first sequence.
__end1 End iterator of first sequence.
__begin2 Begin iterator of second sequence. Second __sequence must have same length as
first sequence.
__pred Find predicate.
__selector _Functionality (e. g. std::find_if(), std::equal(),...)
Returns
Place of finding in both sequences.
See also
__gnu_parallel::_Settings::find_sequential_search_size
__gnu_parallel::_Settings::find_scale_factor
There are two main differences between the growing blocks and the constant-size blocks
variants. 1. For GB, the block size grows; for CSB, the block size is fixed. 2. For GB,
the blocks are allocated dynamically; for CSB, the blocks are allocated in a predetermined
manner, namely spacial round-robin.
Definition at line 185 of file find.h.
References _GLIBCXX_CALL, __gnu_parallel::_Settings::find_scale_factor,
__gnu_parallel::_Settings::find_sequential_search_size, std::pair< _T1, _T2 >::first, and
__gnu_parallel::_Settings::get().
template<typename _IIter , typename _UserOp , typename _Functionality , typename _Red ,
typename _Result > _UserOp __gnu_parallel::__for_each_template_random_access (_IIter
__begin, _IIter __end, _UserOp __user_op, _Functionality & __functionality, _Red
__reduction, _Result __reduction_start, _Result & __output, typename std::iterator_traits<
_IIter >::difference_type __bound, _Parallelism __parallelism_tag)
Chose the desired algorithm by evaluating __parallelism_tag.
Parameters
__begin Begin iterator of input sequence.
__end End iterator of input sequence.
__user_op A user-specified functor (comparator, predicate, associative operator,...)
__functionality functor to process an element with __user_op (depends on desired
functionality, e. g. accumulate, for_each,...
__reduction Reduction functor.
__reduction_start Initial value for reduction.
__output Output iterator.
__bound Maximum number of elements processed.
__parallelism_tag Parallelization method
Definition at line 61 of file for_each.h.
References __for_each_template_random_access_ed(),
__for_each_template_random_access_omp_loop(),
__for_each_template_random_access_workstealing(), parallel_omp_loop,
parallel_omp_loop_static, and parallel_unbalanced.
template<typename _RAIter , typename _Op , typename _Fu , typename _Red , typename _Result >
_Op __gnu_parallel::__for_each_template_random_access_ed (_RAIter __begin, _RAIter __end,
_Op __o, _Fu & __f, _Red __r, _Result __base, _Result & __output, typename
std::iterator_traits< _RAIter >::difference_type __bound)
Embarrassingly parallel algorithm for random access iterators, using hand-crafted
parallelization by equal splitting the work.
Parameters
__begin Begin iterator of element sequence.
__end End iterator of element sequence.
__o User-supplied functor (comparator, predicate, adding functor, ...)
__f Functor to 'process' an element with __op (depends on desired functionality, e. g.
for std::for_each(), ...).
__r Functor to 'add' a single __result to the already processed elements (depends on
functionality).
__base Base value for reduction.
__output Pointer to position where final result is written to
__bound Maximum number of elements processed (e. g. for std::count_n()).
Returns
User-supplied functor (that may contain a part of the result).
Definition at line 67 of file par_loop.h.
References __equally_split_point().
Referenced by __for_each_template_random_access().
template<typename _RAIter , typename _Op , typename _Fu , typename _Red , typename _Result >
_Op __gnu_parallel::__for_each_template_random_access_omp_loop (_RAIter __begin, _RAIter
__end, _Op __o, _Fu & __f, _Red __r, _Result __base, _Result & __output, typename
std::iterator_traits< _RAIter >::difference_type __bound)
Embarrassingly parallel algorithm for random access iterators, using an OpenMP for loop.
Parameters
__begin Begin iterator of element sequence.
__end End iterator of element sequence.
__o User-supplied functor (comparator, predicate, adding functor, etc.).
__f Functor to process an element with __op (depends on desired functionality, e. g.
for std::for_each(), ...).
__r Functor to add a single __result to the already processed elements (depends on
functionality).
__base Base value for reduction.
__output Pointer to position where final result is written to
__bound Maximum number of elements processed (e. g. for std::count_n()).
Returns
User-supplied functor (that may contain a part of the result).
Definition at line 67 of file omp_loop.h.
Referenced by __for_each_template_random_access().
template<typename _RAIter , typename _Op , typename _Fu , typename _Red , typename _Result >
_Op __gnu_parallel::__for_each_template_random_access_omp_loop_static (_RAIter __begin,
_RAIter __end, _Op __o, _Fu & __f, _Red __r, _Result __base, _Result & __output, typename
std::iterator_traits< _RAIter >::difference_type __bound)
Embarrassingly parallel algorithm for random access iterators, using an OpenMP for loop
with static scheduling.
Parameters
__begin Begin iterator of element sequence.
__end End iterator of element sequence.
__o User-supplied functor (comparator, predicate, adding functor, ...).
__f Functor to process an element with __op (depends on desired functionality, e. g.
for std::for_each(), ...).
__r Functor to add a single __result to the already processed __elements (depends on
functionality).
__base Base value for reduction.
__output Pointer to position where final result is written to
__bound Maximum number of elements processed (e. g. for std::count_n()).
Returns
User-supplied functor (that may contain a part of the result).
Definition at line 66 of file omp_loop_static.h.
template<typename _RAIter , typename _Op , typename _Fu , typename _Red , typename _Result >
_Op __gnu_parallel::__for_each_template_random_access_workstealing (_RAIter __begin,
_RAIter __end, _Op __op, _Fu & __f, _Red __r, _Result __base, _Result & __output, typename
std::iterator_traits< _RAIter >::difference_type __bound)
Work stealing algorithm for random access iterators. Uses O(1) additional memory.
Synchronization at job lists is done with atomic operations.
Parameters
__begin Begin iterator of element sequence.
__end End iterator of element sequence.
__op User-supplied functor (comparator, predicate, adding functor, ...).
__f Functor to process an element with __op (depends on desired functionality, e. g.
for std::for_each(), ...).
__r Functor to add a single __result to the already processed elements (depends on
functionality).
__base Base value for reduction.
__output Pointer to position where final result is written to
__bound Maximum number of elements processed (e. g. for std::count_n()).
Returns
User-supplied functor (that may contain a part of the result).
Definition at line 99 of file workstealing.h.
References __gnu_debug::__base(), __yield(), _GLIBCXX_CALL, __gnu_parallel::_Job<
_DifferenceTp >::_M_first, __gnu_parallel::_Job< _DifferenceTp >::_M_last,
__gnu_parallel::_Job< _DifferenceTp >::_M_load,
__gnu_parallel::_Settings::cache_line_size, __gnu_parallel::_Settings::get(), and min().
Referenced by __for_each_template_random_access().
_ThreadIndex __gnu_parallel::__get_max_threads () [inline]
Definition at line 85 of file parallel/base.h.
bool __gnu_parallel::__is_parallel (const _Parallelism __p) [inline]
Definition at line 93 of file parallel/base.h.
template<typename _IIter , typename _Compare > bool __gnu_parallel::__is_sorted (_IIter
__begin, _IIter __end, _Compare __comp)
Check whether [__begin, __end) is sorted according to __comp.
Parameters
__begin Begin iterator of sequence.
__end End iterator of sequence.
__comp Comparator.
Returns
true if sorted, false otherwise.
Definition at line 51 of file checkers.h.
template<typename _RAIter , typename _Compare > _RAIter
__gnu_parallel::__median_of_three_iterators (_RAIter __a, _RAIter __b, _RAIter __c,
_Compare __comp)
Compute the median of three referenced elements, according to __comp.
Parameters
__a First iterator.
__b Second iterator.
__c Third iterator.
__comp Comparator.
Definition at line 398 of file parallel/base.h.
template<typename _RAIter1 , typename _RAIter2 , typename _OutputIterator , typename
_DifferenceTp , typename _Compare > _OutputIterator __gnu_parallel::__merge_advance
(_RAIter1 & __begin1, _RAIter1 __end1, _RAIter2 & __begin2, _RAIter2 __end2,
_OutputIterator __target, _DifferenceTp __max_length, _Compare __comp) [inline]
Merge routine being able to merge only the __max_length smallest elements. The __begin
iterators are advanced accordingly, they might not reach __end, in contrast to the usual
variant. Static switch on whether to use the conditional-move variant.
Parameters
__begin1 Begin iterator of first sequence.
__end1 End iterator of first sequence.
__begin2 Begin iterator of second sequence.
__end2 End iterator of second sequence.
__target Target begin iterator.
__max_length Maximum number of elements to merge.
__comp Comparator.
Returns
Output end iterator.
Definition at line 171 of file merge.h.
References __merge_advance_movc(), and _GLIBCXX_CALL.
Referenced by __parallel_merge_advance().
template<typename _RAIter1 , typename _RAIter2 , typename _OutputIterator , typename
_DifferenceTp , typename _Compare > _OutputIterator __gnu_parallel::__merge_advance_movc
(_RAIter1 & __begin1, _RAIter1 __end1, _RAIter2 & __begin2, _RAIter2 __end2,
_OutputIterator __target, _DifferenceTp __max_length, _Compare __comp)
Merge routine being able to merge only the __max_length smallest elements. The __begin
iterators are advanced accordingly, they might not reach __end, in contrast to the usual
variant. Specially designed code should allow the compiler to generate conditional moves
instead of branches.
Parameters
__begin1 Begin iterator of first sequence.
__end1 End iterator of first sequence.
__begin2 Begin iterator of second sequence.
__end2 End iterator of second sequence.
__target Target begin iterator.
__max_length Maximum number of elements to merge.
__comp Comparator.
Returns
Output end iterator.
Definition at line 105 of file merge.h.
Referenced by __merge_advance().
template<typename _RAIter1 , typename _RAIter2 , typename _OutputIterator , typename
_DifferenceTp , typename _Compare > _OutputIterator __gnu_parallel::__merge_advance_usual
(_RAIter1 & __begin1, _RAIter1 __end1, _RAIter2 & __begin2, _RAIter2 __end2,
_OutputIterator __target, _DifferenceTp __max_length, _Compare __comp)
Merge routine being able to merge only the __max_length smallest elements. The __begin
iterators are advanced accordingly, they might not reach __end, in contrast to the usual
variant.
Parameters
__begin1 Begin iterator of first sequence.
__end1 End iterator of first sequence.
__begin2 Begin iterator of second sequence.
__end2 End iterator of second sequence.
__target Target begin iterator.
__max_length Maximum number of elements to merge.
__comp Comparator.
Returns
Output end iterator.
Definition at line 57 of file merge.h.
template<typename _RAIter1 , typename _RAIter3 , typename _Compare > _RAIter3
__gnu_parallel::__parallel_merge_advance (_RAIter1 & __begin1, _RAIter1 __end1, _RAIter1 &
__begin2, _RAIter1 __end2, _RAIter3 __target, typename std::iterator_traits< _RAIter1
>::difference_type __max_length, _Compare __comp) [inline]
Parallel merge routine being able to merge only the __max_length smallest elements. The
__begin iterators are advanced accordingly, they might not reach __end, in contrast to the
usual variant. The functionality is projected onto parallel_multiway_merge.
Parameters
__begin1 Begin iterator of first sequence.
__end1 End iterator of first sequence.
__begin2 Begin iterator of second sequence.
__end2 End iterator of second sequence.
__target Target begin iterator.
__max_length Maximum number of elements to merge.
__comp Comparator.
Returns
Output end iterator.
Definition at line 223 of file merge.h.
References std::make_pair(), multiway_merge_exact_splitting(), and
parallel_multiway_merge().
template<typename _RAIter1 , typename _RAIter2 , typename _RAIter3 , typename _Compare >
_RAIter3 __gnu_parallel::__parallel_merge_advance (_RAIter1 & __begin1, _RAIter1 __end1,
_RAIter2 & __begin2, _RAIter2 __end2, _RAIter3 __target, typename std::iterator_traits<
_RAIter1 >::difference_type __max_length, _Compare __comp) [inline]
Merge routine fallback to sequential in case the iterators of the two input sequences are
of different type.
Parameters
__begin1 Begin iterator of first sequence.
__end1 End iterator of first sequence.
__begin2 Begin iterator of second sequence.
__end2 End iterator of second sequence.
__target Target begin iterator.
__max_length Maximum number of elements to merge.
__comp Comparator.
Returns
Output end iterator.
Definition at line 195 of file merge.h.
References __merge_advance().
template<typename _RAIter , typename _Compare > void __gnu_parallel::__parallel_nth_element
(_RAIter __begin, _RAIter __nth, _RAIter __end, _Compare __comp)
Parallel implementation of std::nth_element().
Parameters
__begin Begin iterator of input sequence.
__nth _Iterator of element that must be in position afterwards.
__end End iterator of input sequence.
__comp Comparator.
Definition at line 332 of file partition.h.
References __parallel_partition(), _GLIBCXX_CALL, __gnu_parallel::_Settings::get(),
std::max(), __gnu_parallel::_Settings::nth_element_minimal_n, and
__gnu_parallel::_Settings::partition_minimal_n.
Referenced by __parallel_partial_sort().
template<typename _RAIter , typename _Compare > void __gnu_parallel::__parallel_partial_sort
(_RAIter __begin, _RAIter __middle, _RAIter __end, _Compare __comp)
Parallel implementation of std::partial_sort().
Parameters
__begin Begin iterator of input sequence.
__middle Sort until this position.
__end End iterator of input sequence.
__comp Comparator.
Definition at line 422 of file partition.h.
References __parallel_nth_element().
template<typename _IIter , typename _OutputIterator , typename _BinaryOperation >
_OutputIterator __gnu_parallel::__parallel_partial_sum (_IIter __begin, _IIter __end,
_OutputIterator __result, _BinaryOperation __bin_op)
Parallel partial sum front-__end.
Parameters
__begin Begin iterator of input sequence.
__end End iterator of input sequence.
__result Begin iterator of output sequence.
__bin_op Associative binary function.
Returns
End iterator of output sequence.
Definition at line 205 of file partial_sum.h.
References __parallel_partial_sum_linear(), _GLIBCXX_CALL, and
__gnu_parallel::_Settings::get().
template<typename _IIter , typename _OutputIterator , typename _BinaryOperation >
_OutputIterator __gnu_parallel::__parallel_partial_sum_basecase (_IIter __begin, _IIter
__end, _OutputIterator __result, _BinaryOperation __bin_op, typename std::iterator_traits<
_IIter >::value_type __value)
Base case prefix sum routine.
Parameters
__begin Begin iterator of input sequence.
__end End iterator of input sequence.
__result Begin iterator of output sequence.
__bin_op Associative binary function.
__value Start value. Must be passed since the neutral element is unknown in general.
Returns
End iterator of output sequence.
Definition at line 58 of file partial_sum.h.
Referenced by __parallel_partial_sum_linear().
template<typename _IIter , typename _OutputIterator , typename _BinaryOperation >
_OutputIterator __gnu_parallel::__parallel_partial_sum_linear (_IIter __begin, _IIter
__end, _OutputIterator __result, _BinaryOperation __bin_op, typename std::iterator_traits<
_IIter >::difference_type __n)
Parallel partial sum implementation, two-phase approach, no recursion.
Parameters
__begin Begin iterator of input sequence.
__end End iterator of input sequence.
__result Begin iterator of output sequence.
__bin_op Associative binary function.
__n Length of sequence.
Returns
End iterator of output sequence.
Definition at line 89 of file partial_sum.h.
References __equally_split(), __parallel_partial_sum_basecase(), std::accumulate(),
__gnu_parallel::_Settings::get(), and __gnu_parallel::_Settings::partial_sum_dilation.
Referenced by __parallel_partial_sum().
template<typename _RAIter , typename _Predicate > std::iterator_traits< _RAIter
>::difference_type __gnu_parallel::__parallel_partition (_RAIter __begin, _RAIter __end,
_Predicate __pred, _ThreadIndex __num_threads)
Parallel implementation of std::partition.
Parameters
__begin Begin iterator of input sequence to split.
__end End iterator of input sequence to split.
__pred Partition predicate, possibly including some kind of pivot.
__num_threads Maximum number of threads to use for this task.
Returns
Number of elements not fulfilling the predicate.
Definition at line 56 of file partition.h.
References __compare_and_swap(), __fetch_and_add(), _GLIBCXX_CALL, _GLIBCXX_VOLATILE,
__gnu_parallel::_Settings::get(), __gnu_parallel::_Settings::partition_chunk_share, and
__gnu_parallel::_Settings::partition_chunk_size.
Referenced by __parallel_nth_element().
template<typename _RAIter , typename _RandomNumberGenerator > void
__gnu_parallel::__parallel_random_shuffle (_RAIter __begin, _RAIter __end,
_RandomNumberGenerator __rng = _RandomNumber()) [inline]
Parallel random public call.
Parameters
__begin Begin iterator of sequence.
__end End iterator of sequence.
__rng Random number generator to use.
Definition at line 522 of file random_shuffle.h.
References __parallel_random_shuffle_drs().
template<typename _RAIter , typename _RandomNumberGenerator > void
__gnu_parallel::__parallel_random_shuffle_drs (_RAIter __begin, _RAIter __end, typename
std::iterator_traits< _RAIter >::difference_type __n, _ThreadIndex __num_threads,
_RandomNumberGenerator & __rng)
Main parallel random shuffle step.
Parameters
__begin Begin iterator of sequence.
__end End iterator of sequence.
__n Length of sequence.
__num_threads Number of threads to use.
__rng Random number generator to use.
Definition at line 265 of file random_shuffle.h.
References __gnu_parallel::_DRSSorterPU< _RAIter, _RandomNumberGenerator >::__bins_end,
__parallel_random_shuffle_drs_pu(), __rd_log2(), __round_up_to_pow2(),
__sequential_random_shuffle(), _GLIBCXX_CALL, __gnu_parallel::_DRandomShufflingGlobalData<
_RAIter >::_M_bin_proc, __gnu_parallel::_DRSSorterPU< _RAIter, _RandomNumberGenerator
>::_M_bins_begin, __gnu_parallel::_DRandomShufflingGlobalData< _RAIter >::_M_dist,
__gnu_parallel::_DRandomShufflingGlobalData< _RAIter >::_M_num_bins,
__gnu_parallel::_DRandomShufflingGlobalData< _RAIter >::_M_num_bits,
__gnu_parallel::_DRSSorterPU< _RAIter, _RandomNumberGenerator >::_M_num_threads,
__gnu_parallel::_DRSSorterPU< _RAIter, _RandomNumberGenerator >::_M_sd,
__gnu_parallel::_DRSSorterPU< _RAIter, _RandomNumberGenerator >::_M_seed,
__gnu_parallel::_DRandomShufflingGlobalData< _RAIter >::_M_starts,
__gnu_parallel::_DRandomShufflingGlobalData< _RAIter >::_M_temporaries,
__gnu_parallel::_Settings::get(), __gnu_parallel::_Settings::L2_cache_size, std::min(),
and __gnu_parallel::_Settings::TLB_size.
Referenced by __parallel_random_shuffle().
template<typename _RAIter , typename _RandomNumberGenerator > void
__gnu_parallel::__parallel_random_shuffle_drs_pu (_DRSSorterPU< _RAIter,
_RandomNumberGenerator > * __pus)
Random shuffle code executed by each thread.
Parameters
__pus Array of thread-local data records.
Definition at line 122 of file random_shuffle.h.
References __random_number_pow2(), __gnu_parallel::_DRandomShufflingGlobalData< _RAIter
>::_M_dist, __gnu_parallel::_DRandomShufflingGlobalData< _RAIter >::_M_num_bins,
__gnu_parallel::_DRandomShufflingGlobalData< _RAIter >::_M_num_bits,
__gnu_parallel::_DRSSorterPU< _RAIter, _RandomNumberGenerator >::_M_num_threads,
__gnu_parallel::_DRSSorterPU< _RAIter, _RandomNumberGenerator >::_M_sd,
__gnu_parallel::_DRSSorterPU< _RAIter, _RandomNumberGenerator >::_M_seed,
__gnu_parallel::_DRandomShufflingGlobalData< _RAIter >::_M_starts, and std::partial_sum().
Referenced by __parallel_random_shuffle_drs().
template<typename _IIter , typename _OutputIterator , typename _Compare > _OutputIterator
__gnu_parallel::__parallel_set_difference (_IIter __begin1, _IIter __end1, _IIter
__begin2, _IIter __end2, _OutputIterator __result, _Compare __comp) [inline]
Definition at line 503 of file set_operations.h.
template<typename _IIter , typename _OutputIterator , typename _Compare > _OutputIterator
__gnu_parallel::__parallel_set_intersection (_IIter __begin1, _IIter __end1, _IIter
__begin2, _IIter __end2, _OutputIterator __result, _Compare __comp) [inline]
Definition at line 489 of file set_operations.h.
template<typename _IIter , typename _OutputIterator , typename _Operation > _OutputIterator
__gnu_parallel::__parallel_set_operation (_IIter __begin1, _IIter __end1, _IIter __begin2,
_IIter __end2, _OutputIterator __result, _Operation __op)
Definition at line 350 of file set_operations.h.
template<typename _IIter , typename _OutputIterator , typename _Compare > _OutputIterator
__gnu_parallel::__parallel_set_symmetric_difference (_IIter __begin1, _IIter __end1,
_IIter __begin2, _IIter __end2, _OutputIterator __result, _Compare __comp) [inline]
Definition at line 517 of file set_operations.h.
template<typename _IIter , typename _OutputIterator , typename _Compare > _OutputIterator
__gnu_parallel::__parallel_set_union (_IIter __begin1, _IIter __end1, _IIter __begin2,
_IIter __end2, _OutputIterator __result, _Compare __comp) [inline]
Definition at line 475 of file set_operations.h.
template<bool __stable, typename _RAIter , typename _Compare > void
__gnu_parallel::__parallel_sort (_RAIter __begin, _RAIter __end, _Compare __comp,
balanced_quicksort_tag __parallelism) [inline]
Choose balanced quicksort for parallel sorting.
Parameters
__begin Begin iterator of input sequence.
__end End iterator of input sequence.
__comp Comparator.
Template Parameters
__stable Sort stable.
Definition at line 161 of file sort.h.
References _GLIBCXX_CALL.
template<bool __stable, typename _RAIter , typename _Compare > void
__gnu_parallel::__parallel_sort (_RAIter __begin, _RAIter __end, _Compare __comp,
default_parallel_tag __parallelism) [inline]
Choose multiway mergesort with exact splitting, for parallel sorting.
Parameters
__begin Begin iterator of input sequence.
__end End iterator of input sequence.
__comp Comparator.
Template Parameters
__stable Sort stable.
Definition at line 183 of file sort.h.
References __gnu_parallel::parallel_tag::__get_num_threads(), and _GLIBCXX_CALL.
template<bool __stable, typename _RAIter , typename _Compare > void
__gnu_parallel::__parallel_sort (_RAIter __begin, _RAIter __end, _Compare __comp,
multiway_mergesort_exact_tag __parallelism) [inline]
Choose multiway mergesort with exact splitting, for parallel sorting.
Parameters
__begin Begin iterator of input sequence.
__end End iterator of input sequence.
__comp Comparator.
Template Parameters
__stable Sort stable.
Definition at line 99 of file sort.h.
References __gnu_parallel::parallel_tag::__get_num_threads(), and _GLIBCXX_CALL.
template<bool __stable, typename _RAIter , typename _Compare > void
__gnu_parallel::__parallel_sort (_RAIter __begin, _RAIter __end, _Compare __comp,
multiway_mergesort_sampling_tag __parallelism) [inline]
Choose multiway mergesort with splitting by sampling, for parallel sorting.
Parameters
__begin Begin iterator of input sequence.
__end End iterator of input sequence.
__comp Comparator.
Template Parameters
__stable Sort stable.
Definition at line 120 of file sort.h.
References __gnu_parallel::parallel_tag::__get_num_threads(), and _GLIBCXX_CALL.
template<bool __stable, typename _RAIter , typename _Compare > void
__gnu_parallel::__parallel_sort (_RAIter __begin, _RAIter __end, _Compare __comp,
multiway_mergesort_tag __parallelism) [inline]
Choose multiway mergesort, splitting variant at run-time, for parallel sorting.
Parameters
__begin Begin iterator of input sequence.
__end End iterator of input sequence.
__comp Comparator.
Template Parameters
__stable Sort stable.
Definition at line 75 of file sort.h.
References __gnu_parallel::parallel_tag::__get_num_threads(), _GLIBCXX_CALL, and
__gnu_parallel::_Settings::get().
template<bool __stable, typename _RAIter , typename _Compare > void
__gnu_parallel::__parallel_sort (_RAIter __begin, _RAIter __end, _Compare __comp,
parallel_tag __parallelism) [inline]
Choose a parallel sorting algorithm.
Parameters
__begin Begin iterator of input sequence.
__end End iterator of input sequence.
__comp Comparator.
Template Parameters
__stable Sort stable.
Definition at line 203 of file sort.h.
References __gnu_parallel::parallel_tag::__get_num_threads(), __parallel_sort_qs(),
__parallel_sort_qsb(), _GLIBCXX_CALL, and __gnu_parallel::_Settings::get().
template<bool __stable, typename _RAIter , typename _Compare > void
__gnu_parallel::__parallel_sort (_RAIter __begin, _RAIter __end, _Compare __comp,
quicksort_tag __parallelism) [inline]
Choose quicksort for parallel sorting.
Parameters
__begin Begin iterator of input sequence.
__end End iterator of input sequence.
__comp Comparator.
Template Parameters
__stable Sort stable.
Definition at line 140 of file sort.h.
References _GLIBCXX_CALL.
template<typename _RAIter , typename _Compare > void __gnu_parallel::__parallel_sort_qs
(_RAIter __begin, _RAIter __end, _Compare __comp, _ThreadIndex __num_threads)
Unbalanced quicksort main call.
Parameters
__begin Begin iterator of input sequence.
__end End iterator input sequence, ignored.
__comp Comparator.
__num_threads Number of threads that are allowed to work on this part.
Definition at line 154 of file quicksort.h.
References __parallel_sort_qs_conquer(), and _GLIBCXX_CALL.
Referenced by __parallel_sort().
template<typename _RAIter , typename _Compare > void
__gnu_parallel::__parallel_sort_qs_conquer (_RAIter __begin, _RAIter __end, _Compare
__comp, _ThreadIndex __num_threads)
Unbalanced quicksort conquer step.
Parameters
__begin Begin iterator of subsequence.
__end End iterator of subsequence.
__comp Comparator.
__num_threads Number of threads that are allowed to work on this part.
Definition at line 101 of file quicksort.h.
Referenced by __parallel_sort_qs().
template<typename _RAIter , typename _Compare > std::iterator_traits< _RAIter
>::difference_type __gnu_parallel::__parallel_sort_qs_divide (_RAIter __begin, _RAIter
__end, _Compare __comp, typename std::iterator_traits< _RAIter >::difference_type
__pivot_rank, typename std::iterator_traits< _RAIter >::difference_type __num_samples,
_ThreadIndex __num_threads)
Unbalanced quicksort divide step.
Parameters
__begin Begin iterator of subsequence.
__end End iterator of subsequence.
__comp Comparator.
__pivot_rank Desired __rank of the pivot.
__num_samples Choose pivot from that many samples.
__num_threads Number of threads that are allowed to work on this part.
Definition at line 51 of file quicksort.h.
References std::min().
template<typename _RAIter , typename _Compare > void __gnu_parallel::__parallel_sort_qsb
(_RAIter __begin, _RAIter __end, _Compare __comp, _ThreadIndex __num_threads)
Top-level quicksort routine.
Parameters
__begin Begin iterator of sequence.
__end End iterator of sequence.
__comp Comparator.
__num_threads Number of threads that are allowed to work on this part.
Definition at line 433 of file balanced_quicksort.h.
References __qsb_conquer(), __rd_log2(), _GLIBCXX_CALL, __gnu_parallel::_QSBThreadLocal<
_RAIter >::_M_elements_leftover, and std::make_pair().
Referenced by __parallel_sort().
template<typename _IIter , class _OutputIterator > _OutputIterator
__gnu_parallel::__parallel_unique_copy (_IIter __first, _IIter __last, _OutputIterator
__result) [inline]
Parallel std::unique_copy(), without explicit equality predicate.
Parameters
__first Begin iterator of input sequence.
__last End iterator of input sequence.
__result Begin iterator of result __sequence.
Returns
End iterator of result __sequence.
Definition at line 186 of file unique_copy.h.
References __parallel_unique_copy().
template<typename _IIter , class _OutputIterator , class _BinaryPredicate > _OutputIterator
__gnu_parallel::__parallel_unique_copy (_IIter __first, _IIter __last, _OutputIterator
__result, _BinaryPredicate __binary_pred)
Parallel std::unique_copy(), w/__o explicit equality predicate.
Parameters
__first Begin iterator of input sequence.
__last End iterator of input sequence.
__result Begin iterator of result __sequence.
__binary_pred Equality predicate.
Returns
End iterator of result __sequence.
Definition at line 50 of file unique_copy.h.
References _GLIBCXX_CALL.
Referenced by __parallel_unique_copy().
template<typename _RAIter , typename _Compare > void __gnu_parallel::__qsb_conquer
(_QSBThreadLocal< _RAIter > ** __tls, _RAIter __begin, _RAIter __end, _Compare __comp,
_ThreadIndex __iam, _ThreadIndex __num_threads, bool __parent_wait)
Quicksort conquer step.
Parameters
__tls Array of thread-local storages.
__begin Begin iterator of subsequence.
__end End iterator of subsequence.
__comp Comparator.
__iam Number of the thread processing this function.
__num_threads Number of threads that are allowed to work on this part.
Definition at line 174 of file balanced_quicksort.h.
References __qsb_divide(), __qsb_local_sort_with_helping(), and
__gnu_parallel::_QSBThreadLocal< _RAIter >::_M_initial.
Referenced by __parallel_sort_qsb().
template<typename _RAIter , typename _Compare > std::iterator_traits< _RAIter
>::difference_type __gnu_parallel::__qsb_divide (_RAIter __begin, _RAIter __end, _Compare
__comp, _ThreadIndex __num_threads)
Balanced quicksort divide step.
Parameters
__begin Begin iterator of subsequence.
__end End iterator of subsequence.
__comp Comparator.
__num_threads Number of threads that are allowed to work on this part.
Precondition
(__end-__begin)>=1
Definition at line 103 of file balanced_quicksort.h.
Referenced by __qsb_conquer().
template<typename _RAIter , typename _Compare > void
__gnu_parallel::__qsb_local_sort_with_helping (_QSBThreadLocal< _RAIter > ** __tls,
_Compare & __comp, _ThreadIndex __iam, bool __wait)
Quicksort step doing load-balanced local sort.
Parameters
__tls Array of thread-local storages.
__comp Comparator.
__iam Number of the thread processing this function.
Definition at line 250 of file balanced_quicksort.h.
References __gnu_parallel::_QSBThreadLocal< _RAIter >::_M_initial,
__gnu_parallel::_QSBThreadLocal< _RAIter >::_M_num_threads,
__gnu_parallel::_Settings::get(), and
__gnu_parallel::_Settings::sort_qsb_base_case_maximal_n.
Referenced by __qsb_conquer().
template<typename _RandomNumberGenerator > int __gnu_parallel::__random_number_pow2 (int
__logp, _RandomNumberGenerator & __rng) [inline]
Generate a random number in [0,2^__logp).
Parameters
__logp Logarithm (basis 2) of the upper range __bound.
__rng Random number generator to use.
Definition at line 115 of file random_shuffle.h.
Referenced by __parallel_random_shuffle_drs_pu(), and __sequential_random_shuffle().
template<typename _Size > _Size __gnu_parallel::__rd_log2 (_Size __n) [inline]
Calculates the rounded-down logarithm of __n for base 2.
Parameters
__n Argument.
Returns
Returns 0 for any argument <1.
Definition at line 102 of file parallel/base.h.
Referenced by __gnu_parallel::_LoserTreeBase< _Tp, _Compare >::_LoserTreeBase(),
__parallel_random_shuffle_drs(), __parallel_sort_qsb(), __round_up_to_pow2(),
__sequential_random_shuffle(), and multiseq_selection().
template<typename _Tp > _Tp __gnu_parallel::__round_up_to_pow2 (_Tp __x)
Round up to the next greater power of 2.
Parameters
__x _Integer to round up
Definition at line 248 of file random_shuffle.h.
References __rd_log2().
Referenced by __parallel_random_shuffle_drs(), __sequential_random_shuffle(), and
multiseq_selection().
template<typename __RAIter1 , typename __RAIter2 , typename _Pred > __RAIter1
__gnu_parallel::__search_template (__RAIter1 __begin1, __RAIter1 __end1, __RAIter2
__begin2, __RAIter2 __end2, _Pred __pred)
Parallel std::search.
Parameters
__begin1 Begin iterator of first sequence.
__end1 End iterator of first sequence.
__begin2 Begin iterator of second sequence.
__end2 End iterator of second sequence.
__pred Find predicate.
Returns
Place of finding in first sequences.
Definition at line 81 of file search.h.
References __calc_borders(), __equally_split(), _GLIBCXX_CALL, and std::min().
template<bool __stable, bool __sentinels, typename _RAIterIterator , typename _RAIter3 ,
typename _DifferenceTp , typename _Compare > _RAIter3
__gnu_parallel::__sequential_multiway_merge (_RAIterIterator __seqs_begin, _RAIterIterator
__seqs_end, _RAIter3 __target, const typename std::iterator_traits< typename
std::iterator_traits< _RAIterIterator >::value_type::first_type >::value_type &
__sentinel, _DifferenceTp __length, _Compare __comp)
Sequential multi-way merging switch. The _GLIBCXX_PARALLEL_DECISION is based on the
branching factor and runtime settings.
Parameters
__seqs_begin Begin iterator of iterator pair input sequence.
__seqs_end End iterator of iterator pair input sequence.
__target Begin iterator of output sequence.
__comp Comparator.
__length Maximum length to merge, possibly larger than the number of elements
available.
__sentinel The sequences have __a __sentinel element.
Returns
End iterator of output sequence.
Definition at line 920 of file multiway_merge.h.
References _GLIBCXX_CALL.
Referenced by multiway_merge(), and multiway_merge_sentinels().
template<typename _RAIter , typename _RandomNumberGenerator > void
__gnu_parallel::__sequential_random_shuffle (_RAIter __begin, _RAIter __end,
_RandomNumberGenerator & __rng)
Sequential cache-efficient random shuffle.
Parameters
__begin Begin iterator of sequence.
__end End iterator of sequence.
__rng Random number generator to use.
Definition at line 410 of file random_shuffle.h.
References __random_number_pow2(), __rd_log2(), __round_up_to_pow2(),
__sequential_random_shuffle(), __gnu_parallel::_Settings::get(),
__gnu_parallel::_Settings::L2_cache_size, std::min(), std::partial_sum(), and
__gnu_parallel::_Settings::TLB_size.
Referenced by __parallel_random_shuffle_drs(), and __sequential_random_shuffle().
template<typename _IIter > void __gnu_parallel::__shrink (std::vector< _IIter > & __os_starts,
size_t & __count_to_two, size_t & __range_length)
Combines two ranges into one and thus halves the number of ranges.
Parameters
__os_starts Start positions worked on (oversampled).
__count_to_two Counts up to 2.
__range_length Current length of a chunk.
Definition at line 70 of file list_partition.h.
References std::vector< _Tp, _Alloc >::size().
Referenced by __shrink_and_double().
template<typename _IIter > void __gnu_parallel::__shrink_and_double (std::vector< _IIter > &
__os_starts, size_t & __count_to_two, size_t & __range_length, const bool __make_twice)
Shrinks and doubles the ranges.
Parameters
__os_starts Start positions worked on (oversampled).
__count_to_two Counts up to 2.
__range_length Current length of a chunk.
__make_twice Whether the __os_starts is allowed to be grown or not
Definition at line 50 of file list_partition.h.
References __shrink(), std::vector< _Tp, _Alloc >::resize(), and std::vector< _Tp, _Alloc
>::size().
Referenced by list_partition().
void __gnu_parallel::__yield () [inline]
Yield control to another thread, without waiting for the end of the time slice.
Definition at line 121 of file parallel/compatibility.h.
Referenced by __for_each_template_random_access_workstealing().
template<typename _IIter , typename _FunctorType > size_t __gnu_parallel::list_partition
(const _IIter __begin, const _IIter __end, _IIter * __starts, size_t * __lengths, const
int __num_parts, _FunctorType & __f, int __oversampling = 0)
Splits a sequence given by input iterators into parts of almost equal size. The function
needs only one pass over the sequence.
Parameters
__begin Begin iterator of input sequence.
__end End iterator of input sequence.
__starts Start iterators for the resulting parts, dimension __num_parts+1. For
convenience, __starts [__num_parts] contains the end iterator of the sequence.
__lengths Length of the resulting parts.
__num_parts Number of parts to split the sequence into.
__f Functor to be applied to each element by traversing __it
__oversampling Oversampling factor. If 0, then the partitions will differ in at most
$t{thrm{end} - thrm{begin}}$ elements. Otherwise, the ratio between the longest and
the shortest part is bounded by $1/(thrm{oversampling}
Returns
Length of the whole sequence.
Definition at line 101 of file list_partition.h.
References __shrink_and_double(), and std::vector< _Tp, _Alloc >::size().
template<typename _Tp > const _Tp & __gnu_parallel::max (const _Tp & __a, const _Tp & __b)
[inline]
Equivalent to std::max.
Definition at line 150 of file parallel/base.h.
template<typename _Tp > const _Tp & __gnu_parallel::min (const _Tp & __a, const _Tp & __b)
[inline]
Equivalent to std::min.
Definition at line 144 of file parallel/base.h.
Referenced by __for_each_template_random_access_workstealing().
template<typename _RanSeqs , typename _RankType , typename _RankIterator , typename _Compare >
void __gnu_parallel::multiseq_partition (_RanSeqs __begin_seqs, _RanSeqs __end_seqs,
_RankType __rank, _RankIterator __begin_offsets, _Compare __comp = std::less< typename
std::iterator_traits<typename std::iterator_traits<_RanSeqs>::value_type::
first_type>::value_type>())
Splits several sorted sequences at a certain global __rank, resulting in a splitting point
for each sequence. The sequences are passed via a sequence of random-access iterator
pairs, none of the sequences may be empty. If there are several equal elements across the
split, the ones on the __left side will be chosen from sequences with smaller number.
Parameters
__begin_seqs Begin of the sequence of iterator pairs.
__end_seqs End of the sequence of iterator pairs.
__rank The global rank to partition at.
__begin_offsets A random-access __sequence __begin where the __result will be stored
in. Each element of the sequence is an iterator that points to the first element on
the greater part of the respective __sequence.
__comp The ordering functor, defaults to std::less<_Tp>.
Definition at line 122 of file multiseq_selection.h.
References _GLIBCXX_CALL, and std::distance().
template<typename _Tp , typename _RanSeqs , typename _RankType , typename _Compare > _Tp
__gnu_parallel::multiseq_selection (_RanSeqs __begin_seqs, _RanSeqs __end_seqs, _RankType
__rank, _RankType & __offset, _Compare __comp = std::less<_Tp>())
Selects the element at a certain global __rank from several sorted sequences. The
sequences are passed via a sequence of random-access iterator pairs, none of the sequences
may be empty.
Parameters
__begin_seqs Begin of the sequence of iterator pairs.
__end_seqs End of the sequence of iterator pairs.
__rank The global rank to partition at.
__offset The rank of the selected element in the global subsequence of elements equal
to the selected element. If the selected element is unique, this number is 0.
__comp The ordering functor, defaults to std::less.
Definition at line 388 of file multiseq_selection.h.
References __rd_log2(), __round_up_to_pow2(), std::__sample(), _GLIBCXX_CALL,
std::distance(), std::make_pair(), and std::max().
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length,
_Compare __comp, __gnu_parallel::exact_tag __tag)
Definition at line 1444 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length,
_Compare __comp, __gnu_parallel::sampling_tag __tag)
Definition at line 1487 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length,
_Compare __comp, __gnu_parallel::sequential_tag)
Multiway Merge Frontend. Merge the sequences specified by seqs_begin and __seqs_end into
__target. __seqs_begin and __seqs_end must point to a sequence of pairs. These pairs must
contain an iterator to the beginning of a sequence in their first entry and an iterator
the _M_end of the same sequence in their second entry.
Ties are broken arbitrarily. See stable_multiway_merge for a variant that breaks ties by
sequence number but is slower.
The first entries of the pairs (i.e. the begin iterators) will be moved forward.
The output sequence has to provide enough space for all elements that are written to it.
This function will merge the input sequences:
• not stable
• parallel, depending on the input size and Settings
• using sampling for splitting
• not using sentinels
Example:
int sequences[10][10];
for (int __i = 0; __i < 10; ++__i)
for (int __j = 0; __i < 10; ++__j)
sequences[__i][__j] = __j;
int __out[33];
std::vector<std::pair<int*> > seqs;
for (int __i = 0; __i < 10; ++__i)
{ seqs.push(std::make_pair<int*>(sequences[__i],
sequences[__i] + 10)) }
multiway_merge(seqs.begin(), seqs.end(), __target, std::less<int>(), 33);
See also
stable_multiway_merge
Precondition
All input sequences must be sorted.
Target must provide enough space to merge out length elements or the number of
elements in all sequences, whichever is smaller.
Postcondition
[__target, return __value) contains merged __elements from the input sequences.
return __value - __target = min(__length, number of elements in all
sequences).
Template Parameters
_RAIterPairIterator iterator over sequence of pairs of iterators
_RAIterOut iterator over target sequence
_DifferenceTp difference type for the sequence
_Compare strict weak ordering type to compare elements in sequences
Parameters
__seqs_begin __begin of sequence __sequence
__seqs_end _M_end of sequence __sequence
__target target sequence to merge to.
__comp strict weak ordering to use for element comparison.
__length Maximum length to merge, possibly larger than the number of elements
available.
Returns
_M_end iterator of output sequence
Definition at line 1418 of file multiway_merge.h.
References __sequential_multiway_merge(), and _GLIBCXX_CALL.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length,
_Compare __comp, default_parallel_tag __tag)
Definition at line 1544 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length,
_Compare __comp, parallel_tag __tag = parallel_tag(0))
Definition at line 1530 of file multiway_merge.h.
template<template< typename RAI, typename C > class iterator, typename _RAIterIterator ,
typename _RAIter3 , typename _DifferenceTp , typename _Compare > _RAIter3
__gnu_parallel::multiway_merge_3_variant (_RAIterIterator __seqs_begin, _RAIterIterator
__seqs_end, _RAIter3 __target, _DifferenceTp __length, _Compare __comp)
Highly efficient 3-way merging procedure. Merging is done with the algorithm
implementation described by Peter Sanders. Basically, the idea is to minimize the number
of necessary comparison after merging an element. The implementation trick that makes this
fast is that the order of the sequences is stored in the instruction pointer (translated
into labels in C++).
This works well for merging up to 4 sequences.
Note that making the merging stable does not come at a performance hit.
Whether the merging is done guarded or unguarded is selected by the used iterator class.
Parameters
__seqs_begin Begin iterator of iterator pair input sequence.
__seqs_end End iterator of iterator pair input sequence.
__target Begin iterator of output sequence.
__comp Comparator.
__length Maximum length to merge, less equal than the total number of elements
available.
Returns
End iterator of output sequence.
Definition at line 241 of file multiway_merge.h.
References _GLIBCXX_CALL.
template<template< typename RAI, typename C > class iterator, typename _RAIterIterator ,
typename _RAIter3 , typename _DifferenceTp , typename _Compare > _RAIter3
__gnu_parallel::multiway_merge_4_variant (_RAIterIterator __seqs_begin, _RAIterIterator
__seqs_end, _RAIter3 __target, _DifferenceTp __length, _Compare __comp)
Highly efficient 4-way merging procedure. Merging is done with the algorithm
implementation described by Peter Sanders. Basically, the idea is to minimize the number
of necessary comparison after merging an element. The implementation trick that makes this
fast is that the order of the sequences is stored in the instruction pointer (translated
into goto labels in C++).
This works well for merging up to 4 sequences.
Note that making the merging stable does not come at a performance hit.
Whether the merging is done guarded or unguarded is selected by the used iterator class.
Parameters
__seqs_begin Begin iterator of iterator pair input sequence.
__seqs_end End iterator of iterator pair input sequence.
__target Begin iterator of output sequence.
__comp Comparator.
__length Maximum length to merge, less equal than the total number of elements
available.
Returns
End iterator of output sequence.
Definition at line 360 of file multiway_merge.h.
References _GLIBCXX_CALL.
template<bool __stable, typename _RAIterIterator , typename _Compare , typename
_DifferenceType > void __gnu_parallel::multiway_merge_exact_splitting (_RAIterIterator
__seqs_begin, _RAIterIterator __seqs_end, _DifferenceType __length, _DifferenceType
__total_length, _Compare __comp, std::vector< std::pair< _DifferenceType, _DifferenceType
> > * __pieces)
Exact splitting for parallel multiway-merge routine. None of the passed sequences may be
empty.
Definition at line 1120 of file multiway_merge.h.
Referenced by __parallel_merge_advance().
template<typename _LT , typename _RAIterIterator , typename _RAIter3 , typename _DifferenceTp
, typename _Compare > _RAIter3 __gnu_parallel::multiway_merge_loser_tree (_RAIterIterator
__seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, _DifferenceTp __length,
_Compare __comp)
Multi-way merging procedure for a high branching factor, guarded case. This merging
variant uses a LoserTree class as selected by _LT.
Stability is selected through the used LoserTree class _LT.
At least one non-empty sequence is required.
Parameters
__seqs_begin Begin iterator of iterator pair input sequence.
__seqs_end End iterator of iterator pair input sequence.
__target Begin iterator of output sequence.
__comp Comparator.
__length Maximum length to merge, less equal than the total number of elements
available.
Returns
End iterator of output sequence.
Definition at line 491 of file multiway_merge.h.
References _GLIBCXX_CALL, and _GLIBCXX_PARALLEL_LENGTH.
template<typename UnguardedLoserTree , typename _RAIterIterator , typename _RAIter3 , typename
_DifferenceTp , typename _Compare > _RAIter3
__gnu_parallel::multiway_merge_loser_tree_sentinel (_RAIterIterator __seqs_begin,
_RAIterIterator __seqs_end, _RAIter3 __target, const typename std::iterator_traits<
typename std::iterator_traits< _RAIterIterator >::value_type::first_type >::value_type &
__sentinel, _DifferenceTp __length, _Compare __comp)
Multi-way merging procedure for a high branching factor, requiring sentinels to exist.
Template Parameters
UnguardedLoserTree _Loser Tree variant to use for the unguarded merging.
Parameters
__seqs_begin Begin iterator of iterator pair input sequence.
__seqs_end End iterator of iterator pair input sequence.
__target Begin iterator of output sequence.
__comp Comparator.
__length Maximum length to merge, less equal than the total number of elements
available.
Returns
End iterator of output sequence.
Definition at line 662 of file multiway_merge.h.
References _GLIBCXX_CALL.
template<typename _LT , typename _RAIterIterator , typename _RAIter3 , typename _DifferenceTp
, typename _Compare > _RAIter3 __gnu_parallel::multiway_merge_loser_tree_unguarded
(_RAIterIterator __seqs_begin, _RAIterIterator __seqs_end, _RAIter3 __target, const
typename std::iterator_traits< typename std::iterator_traits< _RAIterIterator
>::value_type::first_type >::value_type & __sentinel, _DifferenceTp __length, _Compare
__comp)
Multi-way merging procedure for a high branching factor, unguarded case. Merging is done
using the LoserTree class _LT.
Stability is selected by the used LoserTrees.
Precondition
No input will run out of elements during the merge.
Parameters
__seqs_begin Begin iterator of iterator pair input sequence.
__seqs_end End iterator of iterator pair input sequence.
__target Begin iterator of output sequence.
__comp Comparator.
__length Maximum length to merge, less equal than the total number of elements
available.
Returns
End iterator of output sequence.
Definition at line 574 of file multiway_merge.h.
References _GLIBCXX_CALL.
template<bool __stable, typename _RAIterIterator , typename _Compare , typename
_DifferenceType > void __gnu_parallel::multiway_merge_sampling_splitting (_RAIterIterator
__seqs_begin, _RAIterIterator __seqs_end, _DifferenceType __length, _DifferenceType
__total_length, _Compare __comp, std::vector< std::pair< _DifferenceType, _DifferenceType
> > * __pieces)
Sampling based splitting for parallel multiway-merge routine.
Definition at line 1035 of file multiway_merge.h.
References _GLIBCXX_PARALLEL_LENGTH, __gnu_parallel::_Settings::get(), and
__gnu_parallel::_Settings::merge_oversampling.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::multiway_merge_sentinels
(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target,
_DifferenceTp __length, _Compare __comp, __gnu_parallel::exact_tag __tag)
Definition at line 1808 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::multiway_merge_sentinels
(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target,
_DifferenceTp __length, _Compare __comp, __gnu_parallel::sequential_tag)
Multiway Merge Frontend. Merge the sequences specified by seqs_begin and __seqs_end into
__target. __seqs_begin and __seqs_end must point to a sequence of pairs. These pairs must
contain an iterator to the beginning of a sequence in their first entry and an iterator
the _M_end of the same sequence in their second entry.
Ties are broken arbitrarily. See stable_multiway_merge for a variant that breaks ties by
sequence number but is slower.
The first entries of the pairs (i.e. the begin iterators) will be moved forward
accordingly.
The output sequence has to provide enough space for all elements that are written to it.
This function will merge the input sequences:
• not stable
• parallel, depending on the input size and Settings
• using sampling for splitting
• using sentinels
You have to take care that the element the _M_end iterator points to is readable and
contains a value that is greater than any other non-sentinel value in all sequences.
Example:
int sequences[10][11];
for (int __i = 0; __i < 10; ++__i)
for (int __j = 0; __i < 11; ++__j)
sequences[__i][__j] = __j; // __last one is sentinel!
int __out[33];
std::vector<std::pair<int*> > seqs;
for (int __i = 0; __i < 10; ++__i)
{ seqs.push(std::make_pair<int*>(sequences[__i],
sequences[__i] + 10)) }
multiway_merge(seqs.begin(), seqs.end(), __target, std::less<int>(), 33);
Precondition
All input sequences must be sorted.
Target must provide enough space to merge out length elements or the number of
elements in all sequences, whichever is smaller.
For each __i, __seqs_begin[__i].second must be the end marker of the sequence, but
also reference the one more __sentinel element.
Postcondition
[__target, return __value) contains merged __elements from the input sequences.
return __value - __target = min(__length, number of elements in all
sequences).
See also
stable_multiway_merge_sentinels
Template Parameters
_RAIterPairIterator iterator over sequence of pairs of iterators
_RAIterOut iterator over target sequence
_DifferenceTp difference type for the sequence
_Compare strict weak ordering type to compare elements in sequences
Parameters
__seqs_begin __begin of sequence __sequence
__seqs_end _M_end of sequence __sequence
__target target sequence to merge to.
__comp strict weak ordering to use for element comparison.
__length Maximum length to merge, possibly larger than the number of elements
available.
Returns
_M_end iterator of output sequence
Definition at line 1782 of file multiway_merge.h.
References __sequential_multiway_merge(), and _GLIBCXX_CALL.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::multiway_merge_sentinels
(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target,
_DifferenceTp __length, _Compare __comp, default_parallel_tag __tag)
Definition at line 1911 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::multiway_merge_sentinels
(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target,
_DifferenceTp __length, _Compare __comp, parallel_tag __tag = parallel_tag(0))
Definition at line 1894 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::multiway_merge_sentinels
(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target,
_DifferenceTp __length, _Compare __comp, sampling_tag __tag)
Definition at line 1851 of file multiway_merge.h.
template<bool __stable, bool __sentinels, typename _RAIterIterator , typename _RAIter3 ,
typename _DifferenceTp , typename _Splitter , typename _Compare > _RAIter3
__gnu_parallel::parallel_multiway_merge (_RAIterIterator __seqs_begin, _RAIterIterator
__seqs_end, _RAIter3 __target, _Splitter __splitter, _DifferenceTp __length, _Compare
__comp, _ThreadIndex __num_threads)
Parallel multi-way merge routine. The _GLIBCXX_PARALLEL_DECISION is based on the branching
factor and runtime settings.
Must not be called if the number of sequences is 1.
Template Parameters
_Splitter functor to split input (either __exact or sampling based)
__stable Stable merging incurs a performance penalty.
__sentinel Ignored.
Parameters
__seqs_begin Begin iterator of iterator pair input sequence.
__seqs_end End iterator of iterator pair input sequence.
__target Begin iterator of output sequence.
__comp Comparator.
__length Maximum length to merge, possibly larger than the number of elements
available.
Returns
End iterator of output sequence.
Definition at line 1225 of file multiway_merge.h.
Referenced by __parallel_merge_advance().
template<bool __stable, bool __exact, typename _RAIter , typename _Compare > void
__gnu_parallel::parallel_sort_mwms (_RAIter __begin, _RAIter __end, _Compare __comp,
_ThreadIndex __num_threads)
PMWMS main call.
Parameters
__begin Begin iterator of sequence.
__end End iterator of sequence.
__comp Comparator.
__num_threads Number of threads to use.
Definition at line 395 of file multiway_mergesort.h.
References _GLIBCXX_CALL.
template<bool __stable, bool __exact, typename _RAIter , typename _Compare > void
__gnu_parallel::parallel_sort_mwms_pu (_PMWMSSortingData< _RAIter > * __sd, _Compare &
__comp)
PMWMS code executed by each thread.
Parameters
__sd Pointer to algorithm data.
__comp Comparator.
Definition at line 308 of file multiway_mergesort.h.
References __gnu_parallel::_PMWMSSortingData< _RAIter >::_M_num_threads,
__gnu_parallel::_PMWMSSortingData< _RAIter >::_M_pieces,
__gnu_parallel::_PMWMSSortingData< _RAIter >::_M_source,
__gnu_parallel::_PMWMSSortingData< _RAIter >::_M_starts,
__gnu_parallel::_PMWMSSortingData< _RAIter >::_M_temporary,
__gnu_parallel::_Settings::get(), std::make_pair(),
__gnu_parallel::_Settings::sort_mwms_oversampling, and std::uninitialized_copy().
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::stable_multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length,
_Compare __comp, __gnu_parallel::exact_tag __tag)
Definition at line 1585 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::stable_multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length,
_Compare __comp, __gnu_parallel::sequential_tag)
Definition at line 1559 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::stable_multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length,
_Compare __comp, default_parallel_tag __tag)
Definition at line 1688 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::stable_multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length,
_Compare __comp, parallel_tag __tag = parallel_tag(0))
Definition at line 1671 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::stable_multiway_merge (_RAIterPairIterator
__seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target, _DifferenceTp __length,
_Compare __comp, sampling_tag __tag)
Definition at line 1628 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::stable_multiway_merge_sentinels
(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target,
_DifferenceTp __length, _Compare __comp, __gnu_parallel::exact_tag __tag)
Definition at line 1955 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::stable_multiway_merge_sentinels
(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target,
_DifferenceTp __length, _Compare __comp, __gnu_parallel::sequential_tag)
Definition at line 1929 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::stable_multiway_merge_sentinels
(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target,
_DifferenceTp __length, _Compare __comp, default_parallel_tag __tag)
Definition at line 2060 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::stable_multiway_merge_sentinels
(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target,
_DifferenceTp __length, _Compare __comp, parallel_tag __tag = parallel_tag(0))
Definition at line 2042 of file multiway_merge.h.
template<typename _RAIterPairIterator , typename _RAIterOut , typename _DifferenceTp ,
typename _Compare > _RAIterOut __gnu_parallel::stable_multiway_merge_sentinels
(_RAIterPairIterator __seqs_begin, _RAIterPairIterator __seqs_end, _RAIterOut __target,
_DifferenceTp __length, _Compare __comp, sampling_tag __tag)
Definition at line 1998 of file multiway_merge.h.
Variable Documentation
const int __gnu_parallel::_CASable_bits [static]
Number of bits of _CASable.
Definition at line 130 of file types.h.
Referenced by __decode2(), and __encode2().
const _CASable __gnu_parallel::_CASable_mask [static]
_CASable with the right half of bits set to 1.
Definition at line 133 of file types.h.
Referenced by __decode2().
Author
Generated automatically by Doxygen for libstdc++ from the source code.