diff options
Diffstat (limited to 'boost/sort/spreadsort/detail')
| -rw-r--r-- | boost/sort/spreadsort/detail/constants.hpp | 92 | ||||
| -rw-r--r-- | boost/sort/spreadsort/detail/float_sort.hpp | 1662 | ||||
| -rw-r--r-- | boost/sort/spreadsort/detail/integer_sort.hpp | 988 | ||||
| -rw-r--r-- | boost/sort/spreadsort/detail/spreadsort_common.hpp | 248 | ||||
| -rw-r--r-- | boost/sort/spreadsort/detail/string_sort.hpp | 1638 |
5 files changed, 2314 insertions, 2314 deletions
diff --git a/boost/sort/spreadsort/detail/constants.hpp b/boost/sort/spreadsort/detail/constants.hpp index a134761e59..9eebc43c69 100644 --- a/boost/sort/spreadsort/detail/constants.hpp +++ b/boost/sort/spreadsort/detail/constants.hpp @@ -1,46 +1,46 @@ -//constant definitions for the Boost Sort library
-
-// Copyright Steven J. Ross 2001 - 2014
-// Distributed under the Boost Software License, Version 1.0.
-// (See accompanying file LICENSE_1_0.txt or copy at
-// http://www.boost.org/LICENSE_1_0.txt)
-
-// See http://www.boost.org/libs/sort for library home page.
-#ifndef BOOST_SORT_SPREADSORT_DETAIL_CONSTANTS
-#define BOOST_SORT_SPREADSORT_DETAIL_CONSTANTS
-namespace boost {
-namespace sort {
-namespace spreadsort {
-namespace detail {
-//Tuning constants
-//This should be tuned to your processor cache;
-//if you go too large you get cache misses on bins
-//The smaller this number, the less worst-case memory usage.
-//If too small, too many recursions slow down spreadsort
-enum { max_splits = 11,
-//It's better to have a few cache misses and finish sorting
-//than to run another iteration
-max_finishing_splits = max_splits + 1,
-//Sets the minimum number of items per bin.
-int_log_mean_bin_size = 2,
-//Used to force a comparison-based sorting for small bins, if it's faster.
-//Minimum value 1
-int_log_min_split_count = 9,
-//This is the minimum split count to use spreadsort when it will finish in one
-//iteration. Make this larger the faster std::sort is relative to integer_sort.
-int_log_finishing_count = 31,
-//Sets the minimum number of items per bin for floating point.
-float_log_mean_bin_size = 2,
-//Used to force a comparison-based sorting for small bins, if it's faster.
-//Minimum value 1
-float_log_min_split_count = 8,
-//This is the minimum split count to use spreadsort when it will finish in one
-//iteration. Make this larger the faster std::sort is relative to float_sort.
-float_log_finishing_count = 4,
-//There is a minimum size below which it is not worth using spreadsort
-min_sort_size = 1000 };
-}
-}
-}
-}
-#endif
+//constant definitions for the Boost Sort library + +// Copyright Steven J. Ross 2001 - 2014 +// Distributed under the Boost Software License, Version 1.0. +// (See accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) + +// See http://www.boost.org/libs/sort for library home page. +#ifndef BOOST_SORT_SPREADSORT_DETAIL_CONSTANTS +#define BOOST_SORT_SPREADSORT_DETAIL_CONSTANTS +namespace boost { +namespace sort { +namespace spreadsort { +namespace detail { +//Tuning constants +//This should be tuned to your processor cache; +//if you go too large you get cache misses on bins +//The smaller this number, the less worst-case memory usage. +//If too small, too many recursions slow down spreadsort +enum { max_splits = 11, +//It's better to have a few cache misses and finish sorting +//than to run another iteration +max_finishing_splits = max_splits + 1, +//Sets the minimum number of items per bin. +int_log_mean_bin_size = 2, +//Used to force a comparison-based sorting for small bins, if it's faster. +//Minimum value 1 +int_log_min_split_count = 9, +//This is the minimum split count to use spreadsort when it will finish in one +//iteration. Make this larger the faster std::sort is relative to integer_sort. +int_log_finishing_count = 31, +//Sets the minimum number of items per bin for floating point. +float_log_mean_bin_size = 2, +//Used to force a comparison-based sorting for small bins, if it's faster. +//Minimum value 1 +float_log_min_split_count = 8, +//This is the minimum split count to use spreadsort when it will finish in one +//iteration. Make this larger the faster std::sort is relative to float_sort. +float_log_finishing_count = 4, +//There is a minimum size below which it is not worth using spreadsort +min_sort_size = 1000 }; +} +} +} +} +#endif diff --git a/boost/sort/spreadsort/detail/float_sort.hpp b/boost/sort/spreadsort/detail/float_sort.hpp index 03dcbaf4f6..93aaa2f69e 100644 --- a/boost/sort/spreadsort/detail/float_sort.hpp +++ b/boost/sort/spreadsort/detail/float_sort.hpp @@ -1,831 +1,831 @@ -// Details for templated Spreadsort-based float_sort.
-
-// Copyright Steven J. Ross 2001 - 2014.
-// Distributed under the Boost Software License, Version 1.0.
-// (See accompanying file LICENSE_1_0.txt or copy at
-// http://www.boost.org/LICENSE_1_0.txt)
-
-// See http://www.boost.org/libs/sort for library home page.
-
-/*
-Some improvements suggested by:
-Phil Endecott and Frank Gennari
-float_mem_cast fix provided by:
-Scott McMurray
-*/
-
-#ifndef BOOST_SORT_SPREADSORT_DETAIL_FLOAT_SORT_HPP
-#define BOOST_SORT_SPREADSORT_DETAIL_FLOAT_SORT_HPP
-#include <algorithm>
-#include <vector>
-#include <limits>
-#include <functional>
-#include <boost/static_assert.hpp>
-#include <boost/serialization/static_warning.hpp>
-#include <boost/utility/enable_if.hpp>
-#include <boost/sort/spreadsort/detail/constants.hpp>
-#include <boost/sort/spreadsort/detail/integer_sort.hpp>
-#include <boost/sort/spreadsort/detail/spreadsort_common.hpp>
-#include <boost/cstdint.hpp>
-
-namespace boost {
-namespace sort {
-namespace spreadsort {
- namespace detail {
- //Casts a RandomAccessIter to the specified integer type
- template<class Cast_type, class RandomAccessIter>
- inline Cast_type
- cast_float_iter(const RandomAccessIter & floatiter)
- {
- typedef typename std::iterator_traits<RandomAccessIter>::value_type
- Data_type;
- //Only cast IEEE floating-point numbers, and only to same-sized integers
- BOOST_STATIC_ASSERT(sizeof(Cast_type) == sizeof(Data_type));
- BOOST_STATIC_ASSERT(std::numeric_limits<Data_type>::is_iec559);
- BOOST_STATIC_ASSERT(std::numeric_limits<Cast_type>::is_integer);
- Cast_type result;
- std::memcpy(&result, &(*floatiter), sizeof(Data_type));
- return result;
- }
-
- // Return true if the list is sorted. Otherwise, find the minimum and
- // maximum. Values are Right_shifted 0 bits before comparison.
- template <class RandomAccessIter, class Div_type, class Right_shift>
- inline bool
- is_sorted_or_find_extremes(RandomAccessIter current, RandomAccessIter last,
- Div_type & max, Div_type & min, Right_shift rshift)
- {
- min = max = rshift(*current, 0);
- RandomAccessIter prev = current;
- bool sorted = true;
- while (++current < last) {
- Div_type value = rshift(*current, 0);
- sorted &= *current >= *prev;
- prev = current;
- if (max < value)
- max = value;
- else if (value < min)
- min = value;
- }
- return sorted;
- }
-
- // Return true if the list is sorted. Otherwise, find the minimum and
- // maximum. Uses comp to check if the data is already sorted.
- template <class RandomAccessIter, class Div_type, class Right_shift,
- class Compare>
- inline bool
- is_sorted_or_find_extremes(RandomAccessIter current, RandomAccessIter last,
- Div_type & max, Div_type & min,
- Right_shift rshift, Compare comp)
- {
- min = max = rshift(*current, 0);
- RandomAccessIter prev = current;
- bool sorted = true;
- while (++current < last) {
- Div_type value = rshift(*current, 0);
- sorted &= !comp(*current, *prev);
- prev = current;
- if (max < value)
- max = value;
- else if (value < min)
- min = value;
- }
- return sorted;
- }
-
- //Specialized swap loops for floating-point casting
- template <class RandomAccessIter, class Div_type>
- inline void inner_float_swap_loop(RandomAccessIter * bins,
- const RandomAccessIter & nextbinstart, unsigned ii
- , const unsigned log_divisor, const Div_type div_min)
- {
- RandomAccessIter * local_bin = bins + ii;
- for (RandomAccessIter current = *local_bin; current < nextbinstart;
- ++current) {
- for (RandomAccessIter * target_bin =
- (bins + ((cast_float_iter<Div_type, RandomAccessIter>(current) >>
- log_divisor) - div_min)); target_bin != local_bin;
- target_bin = bins + ((cast_float_iter<Div_type, RandomAccessIter>
- (current) >> log_divisor) - div_min)) {
- typename std::iterator_traits<RandomAccessIter>::value_type tmp;
- RandomAccessIter b = (*target_bin)++;
- RandomAccessIter * b_bin = bins + ((cast_float_iter<Div_type,
- RandomAccessIter>(b) >> log_divisor) - div_min);
- //Three-way swap; if the item to be swapped doesn't belong in the
- //current bin, swap it to where it belongs
- if (b_bin != local_bin) {
- RandomAccessIter c = (*b_bin)++;
- tmp = *c;
- *c = *b;
- }
- else
- tmp = *b;
- *b = *current;
- *current = tmp;
- }
- }
- *local_bin = nextbinstart;
- }
-
- template <class RandomAccessIter, class Div_type>
- inline void float_swap_loop(RandomAccessIter * bins,
- RandomAccessIter & nextbinstart, unsigned ii,
- const size_t *bin_sizes,
- const unsigned log_divisor, const Div_type div_min)
- {
- nextbinstart += bin_sizes[ii];
- inner_float_swap_loop<RandomAccessIter, Div_type>
- (bins, nextbinstart, ii, log_divisor, div_min);
- }
-
- // Return true if the list is sorted. Otherwise, find the minimum and
- // maximum. Values are cast to Cast_type before comparison.
- template <class RandomAccessIter, class Cast_type>
- inline bool
- is_sorted_or_find_extremes(RandomAccessIter current, RandomAccessIter last,
- Cast_type & max, Cast_type & min)
- {
- min = max = cast_float_iter<Cast_type, RandomAccessIter>(current);
- RandomAccessIter prev = current;
- bool sorted = true;
- while (++current < last) {
- Cast_type value = cast_float_iter<Cast_type, RandomAccessIter>(current);
- sorted &= *current >= *prev;
- prev = current;
- if (max < value)
- max = value;
- else if (value < min)
- min = value;
- }
- return sorted;
- }
-
- //Special-case sorting of positive floats with casting
- template <class RandomAccessIter, class Div_type, class Size_type>
- inline void
- positive_float_sort_rec(RandomAccessIter first, RandomAccessIter last,
- std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset
- , size_t *bin_sizes)
- {
- Div_type max, min;
- if (is_sorted_or_find_extremes<RandomAccessIter, Div_type>(first, last,
- max, min))
- return;
- unsigned log_divisor = get_log_divisor<float_log_mean_bin_size>(
- last - first, rough_log_2_size(Size_type(max - min)));
- Div_type div_min = min >> log_divisor;
- Div_type div_max = max >> log_divisor;
- unsigned bin_count = unsigned(div_max - div_min) + 1;
- unsigned cache_end;
- RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset,
- cache_end, bin_count);
-
- //Calculating the size of each bin
- for (RandomAccessIter current = first; current != last;)
- bin_sizes[unsigned((cast_float_iter<Div_type, RandomAccessIter>(
- current++) >> log_divisor) - div_min)]++;
- bins[0] = first;
- for (unsigned u = 0; u < bin_count - 1; u++)
- bins[u + 1] = bins[u] + bin_sizes[u];
-
-
- //Swap into place
- RandomAccessIter nextbinstart = first;
- for (unsigned u = 0; u < bin_count - 1; ++u)
- float_swap_loop<RandomAccessIter, Div_type>
- (bins, nextbinstart, u, bin_sizes, log_divisor, div_min);
- bins[bin_count - 1] = last;
-
- //Return if we've completed bucketsorting
- if (!log_divisor)
- return;
-
- //Recursing
- size_t max_count = get_min_count<float_log_mean_bin_size,
- float_log_min_split_count,
- float_log_finishing_count>(log_divisor);
- RandomAccessIter lastPos = first;
- for (unsigned u = cache_offset; u < cache_end; lastPos = bin_cache[u],
- ++u) {
- size_t count = bin_cache[u] - lastPos;
- if (count < 2)
- continue;
- if (count < max_count)
- std::sort(lastPos, bin_cache[u]);
- else
- positive_float_sort_rec<RandomAccessIter, Div_type, Size_type>
- (lastPos, bin_cache[u], bin_cache, cache_end, bin_sizes);
- }
- }
-
- //Sorting negative floats
- //Bins are iterated in reverse because max_neg_float = min_neg_int
- template <class RandomAccessIter, class Div_type, class Size_type>
- inline void
- negative_float_sort_rec(RandomAccessIter first, RandomAccessIter last,
- std::vector<RandomAccessIter> &bin_cache,
- unsigned cache_offset, size_t *bin_sizes)
- {
- Div_type max, min;
- if (is_sorted_or_find_extremes<RandomAccessIter, Div_type>(first, last,
- max, min))
- return;
-
- unsigned log_divisor = get_log_divisor<float_log_mean_bin_size>(
- last - first, rough_log_2_size(Size_type(max - min)));
- Div_type div_min = min >> log_divisor;
- Div_type div_max = max >> log_divisor;
- unsigned bin_count = unsigned(div_max - div_min) + 1;
- unsigned cache_end;
- RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset,
- cache_end, bin_count);
-
- //Calculating the size of each bin
- for (RandomAccessIter current = first; current != last;)
- bin_sizes[unsigned((cast_float_iter<Div_type, RandomAccessIter>(
- current++) >> log_divisor) - div_min)]++;
- bins[bin_count - 1] = first;
- for (int ii = bin_count - 2; ii >= 0; --ii)
- bins[ii] = bins[ii + 1] + bin_sizes[ii + 1];
-
- //Swap into place
- RandomAccessIter nextbinstart = first;
- //The last bin will always have the correct elements in it
- for (int ii = bin_count - 1; ii > 0; --ii)
- float_swap_loop<RandomAccessIter, Div_type>
- (bins, nextbinstart, ii, bin_sizes, log_divisor, div_min);
- //Update the end position because we don't process the last bin
- bin_cache[cache_offset] = last;
-
- //Return if we've completed bucketsorting
- if (!log_divisor)
- return;
-
- //Recursing
- size_t max_count = get_min_count<float_log_mean_bin_size,
- float_log_min_split_count,
- float_log_finishing_count>(log_divisor);
- RandomAccessIter lastPos = first;
- for (int ii = cache_end - 1; ii >= static_cast<int>(cache_offset);
- lastPos = bin_cache[ii], --ii) {
- size_t count = bin_cache[ii] - lastPos;
- if (count < 2)
- continue;
- if (count < max_count)
- std::sort(lastPos, bin_cache[ii]);
- else
- negative_float_sort_rec<RandomAccessIter, Div_type, Size_type>
- (lastPos, bin_cache[ii], bin_cache, cache_end, bin_sizes);
- }
- }
-
- //Sorting negative floats
- //Bins are iterated in reverse order because max_neg_float = min_neg_int
- template <class RandomAccessIter, class Div_type, class Right_shift,
- class Size_type>
- inline void
- negative_float_sort_rec(RandomAccessIter first, RandomAccessIter last,
- std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset
- , size_t *bin_sizes, Right_shift rshift)
- {
- Div_type max, min;
- if (is_sorted_or_find_extremes(first, last, max, min, rshift))
- return;
- unsigned log_divisor = get_log_divisor<float_log_mean_bin_size>(
- last - first, rough_log_2_size(Size_type(max - min)));
- Div_type div_min = min >> log_divisor;
- Div_type div_max = max >> log_divisor;
- unsigned bin_count = unsigned(div_max - div_min) + 1;
- unsigned cache_end;
- RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset,
- cache_end, bin_count);
-
- //Calculating the size of each bin
- for (RandomAccessIter current = first; current != last;)
- bin_sizes[unsigned(rshift(*(current++), log_divisor) - div_min)]++;
- bins[bin_count - 1] = first;
- for (int ii = bin_count - 2; ii >= 0; --ii)
- bins[ii] = bins[ii + 1] + bin_sizes[ii + 1];
-
- //Swap into place
- RandomAccessIter nextbinstart = first;
- //The last bin will always have the correct elements in it
- for (int ii = bin_count - 1; ii > 0; --ii)
- swap_loop<RandomAccessIter, Div_type, Right_shift>
- (bins, nextbinstart, ii, rshift, bin_sizes, log_divisor, div_min);
- //Update the end position of the unprocessed last bin
- bin_cache[cache_offset] = last;
-
- //Return if we've completed bucketsorting
- if (!log_divisor)
- return;
-
- //Recursing
- size_t max_count = get_min_count<float_log_mean_bin_size,
- float_log_min_split_count,
- float_log_finishing_count>(log_divisor);
- RandomAccessIter lastPos = first;
- for (int ii = cache_end - 1; ii >= static_cast<int>(cache_offset);
- lastPos = bin_cache[ii], --ii) {
- size_t count = bin_cache[ii] - lastPos;
- if (count < 2)
- continue;
- if (count < max_count)
- std::sort(lastPos, bin_cache[ii]);
- else
- negative_float_sort_rec<RandomAccessIter, Div_type, Right_shift,
- Size_type>
- (lastPos, bin_cache[ii], bin_cache, cache_end, bin_sizes, rshift);
- }
- }
-
- template <class RandomAccessIter, class Div_type, class Right_shift,
- class Compare, class Size_type>
- inline void
- negative_float_sort_rec(RandomAccessIter first, RandomAccessIter last,
- std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset,
- size_t *bin_sizes, Right_shift rshift, Compare comp)
- {
- Div_type max, min;
- if (is_sorted_or_find_extremes(first, last, max, min, rshift, comp))
- return;
- unsigned log_divisor = get_log_divisor<float_log_mean_bin_size>(
- last - first, rough_log_2_size(Size_type(max - min)));
- Div_type div_min = min >> log_divisor;
- Div_type div_max = max >> log_divisor;
- unsigned bin_count = unsigned(div_max - div_min) + 1;
- unsigned cache_end;
- RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset,
- cache_end, bin_count);
-
- //Calculating the size of each bin
- for (RandomAccessIter current = first; current != last;)
- bin_sizes[unsigned(rshift(*(current++), log_divisor) - div_min)]++;
- bins[bin_count - 1] = first;
- for (int ii = bin_count - 2; ii >= 0; --ii)
- bins[ii] = bins[ii + 1] + bin_sizes[ii + 1];
-
- //Swap into place
- RandomAccessIter nextbinstart = first;
- //The last bin will always have the correct elements in it
- for (int ii = bin_count - 1; ii > 0; --ii)
- swap_loop<RandomAccessIter, Div_type, Right_shift>
- (bins, nextbinstart, ii, rshift, bin_sizes, log_divisor, div_min);
- //Update the end position of the unprocessed last bin
- bin_cache[cache_offset] = last;
-
- //Return if we've completed bucketsorting
- if (!log_divisor)
- return;
-
- //Recursing
- size_t max_count = get_min_count<float_log_mean_bin_size,
- float_log_min_split_count,
- float_log_finishing_count>(log_divisor);
- RandomAccessIter lastPos = first;
- for (int ii = cache_end - 1; ii >= static_cast<int>(cache_offset);
- lastPos = bin_cache[ii], --ii) {
- size_t count = bin_cache[ii] - lastPos;
- if (count < 2)
- continue;
- if (count < max_count)
- std::sort(lastPos, bin_cache[ii], comp);
- else
- negative_float_sort_rec<RandomAccessIter, Div_type, Right_shift,
- Compare, Size_type>(lastPos, bin_cache[ii],
- bin_cache, cache_end,
- bin_sizes, rshift, comp);
- }
- }
-
- //Casting special-case for floating-point sorting
- template <class RandomAccessIter, class Div_type, class Size_type>
- inline void
- float_sort_rec(RandomAccessIter first, RandomAccessIter last,
- std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset
- , size_t *bin_sizes)
- {
- Div_type max, min;
- if (is_sorted_or_find_extremes<RandomAccessIter, Div_type>(first, last,
- max, min))
- return;
- unsigned log_divisor = get_log_divisor<float_log_mean_bin_size>(
- last - first, rough_log_2_size(Size_type(max - min)));
- Div_type div_min = min >> log_divisor;
- Div_type div_max = max >> log_divisor;
- unsigned bin_count = unsigned(div_max - div_min) + 1;
- unsigned cache_end;
- RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset,
- cache_end, bin_count);
-
- //Calculating the size of each bin
- for (RandomAccessIter current = first; current != last;)
- bin_sizes[unsigned((cast_float_iter<Div_type, RandomAccessIter>(
- current++) >> log_divisor) - div_min)]++;
- //The index of the first positive bin
- //Must be divided small enough to fit into an integer
- unsigned first_positive = (div_min < 0) ? unsigned(-div_min) : 0;
- //Resetting if all bins are negative
- if (cache_offset + first_positive > cache_end)
- first_positive = cache_end - cache_offset;
- //Reversing the order of the negative bins
- //Note that because of the negative/positive ordering direction flip
- //We can not depend upon bin order and positions matching up
- //so bin_sizes must be reused to contain the end of the bin
- if (first_positive > 0) {
- bins[first_positive - 1] = first;
- for (int ii = first_positive - 2; ii >= 0; --ii) {
- bins[ii] = first + bin_sizes[ii + 1];
- bin_sizes[ii] += bin_sizes[ii + 1];
- }
- //Handling positives following negatives
- if (first_positive < bin_count) {
- bins[first_positive] = first + bin_sizes[0];
- bin_sizes[first_positive] += bin_sizes[0];
- }
- }
- else
- bins[0] = first;
- for (unsigned u = first_positive; u < bin_count - 1; u++) {
- bins[u + 1] = first + bin_sizes[u];
- bin_sizes[u + 1] += bin_sizes[u];
- }
-
- //Swap into place
- RandomAccessIter nextbinstart = first;
- for (unsigned u = 0; u < bin_count; ++u) {
- nextbinstart = first + bin_sizes[u];
- inner_float_swap_loop<RandomAccessIter, Div_type>
- (bins, nextbinstart, u, log_divisor, div_min);
- }
-
- if (!log_divisor)
- return;
-
- //Handling negative values first
- size_t max_count = get_min_count<float_log_mean_bin_size,
- float_log_min_split_count,
- float_log_finishing_count>(log_divisor);
- RandomAccessIter lastPos = first;
- for (int ii = cache_offset + first_positive - 1;
- ii >= static_cast<int>(cache_offset);
- lastPos = bin_cache[ii--]) {
- size_t count = bin_cache[ii] - lastPos;
- if (count < 2)
- continue;
- if (count < max_count)
- std::sort(lastPos, bin_cache[ii]);
- //sort negative values using reversed-bin spreadsort
- else
- negative_float_sort_rec<RandomAccessIter, Div_type, Size_type>
- (lastPos, bin_cache[ii], bin_cache, cache_end, bin_sizes);
- }
-
- for (unsigned u = cache_offset + first_positive; u < cache_end;
- lastPos = bin_cache[u], ++u) {
- size_t count = bin_cache[u] - lastPos;
- if (count < 2)
- continue;
- if (count < max_count)
- std::sort(lastPos, bin_cache[u]);
- //sort positive values using normal spreadsort
- else
- positive_float_sort_rec<RandomAccessIter, Div_type, Size_type>
- (lastPos, bin_cache[u], bin_cache, cache_end, bin_sizes);
- }
- }
-
- //Functor implementation for recursive sorting
- template <class RandomAccessIter, class Div_type, class Right_shift
- , class Size_type>
- inline void
- float_sort_rec(RandomAccessIter first, RandomAccessIter last,
- std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset
- , size_t *bin_sizes, Right_shift rshift)
- {
- Div_type max, min;
- if (is_sorted_or_find_extremes(first, last, max, min, rshift))
- return;
- unsigned log_divisor = get_log_divisor<float_log_mean_bin_size>(
- last - first, rough_log_2_size(Size_type(max - min)));
- Div_type div_min = min >> log_divisor;
- Div_type div_max = max >> log_divisor;
- unsigned bin_count = unsigned(div_max - div_min) + 1;
- unsigned cache_end;
- RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset,
- cache_end, bin_count);
-
- //Calculating the size of each bin
- for (RandomAccessIter current = first; current != last;)
- bin_sizes[unsigned(rshift(*(current++), log_divisor) - div_min)]++;
- //The index of the first positive bin
- unsigned first_positive = (div_min < 0) ? unsigned(-div_min) : 0;
- //Resetting if all bins are negative
- if (cache_offset + first_positive > cache_end)
- first_positive = cache_end - cache_offset;
- //Reversing the order of the negative bins
- //Note that because of the negative/positive ordering direction flip
- //We can not depend upon bin order and positions matching up
- //so bin_sizes must be reused to contain the end of the bin
- if (first_positive > 0) {
- bins[first_positive - 1] = first;
- for (int ii = first_positive - 2; ii >= 0; --ii) {
- bins[ii] = first + bin_sizes[ii + 1];
- bin_sizes[ii] += bin_sizes[ii + 1];
- }
- //Handling positives following negatives
- if (static_cast<unsigned>(first_positive) < bin_count) {
- bins[first_positive] = first + bin_sizes[0];
- bin_sizes[first_positive] += bin_sizes[0];
- }
- }
- else
- bins[0] = first;
- for (unsigned u = first_positive; u < bin_count - 1; u++) {
- bins[u + 1] = first + bin_sizes[u];
- bin_sizes[u + 1] += bin_sizes[u];
- }
-
- //Swap into place
- RandomAccessIter next_bin_start = first;
- for (unsigned u = 0; u < bin_count; ++u) {
- next_bin_start = first + bin_sizes[u];
- inner_swap_loop<RandomAccessIter, Div_type, Right_shift>
- (bins, next_bin_start, u, rshift, log_divisor, div_min);
- }
-
- //Return if we've completed bucketsorting
- if (!log_divisor)
- return;
-
- //Handling negative values first
- size_t max_count = get_min_count<float_log_mean_bin_size,
- float_log_min_split_count,
- float_log_finishing_count>(log_divisor);
- RandomAccessIter lastPos = first;
- for (int ii = cache_offset + first_positive - 1;
- ii >= static_cast<int>(cache_offset);
- lastPos = bin_cache[ii--]) {
- size_t count = bin_cache[ii] - lastPos;
- if (count < 2)
- continue;
- if (count < max_count)
- std::sort(lastPos, bin_cache[ii]);
- //sort negative values using reversed-bin spreadsort
- else
- negative_float_sort_rec<RandomAccessIter, Div_type,
- Right_shift, Size_type>(lastPos, bin_cache[ii], bin_cache,
- cache_end, bin_sizes, rshift);
- }
-
- for (unsigned u = cache_offset + first_positive; u < cache_end;
- lastPos = bin_cache[u], ++u) {
- size_t count = bin_cache[u] - lastPos;
- if (count < 2)
- continue;
- if (count < max_count)
- std::sort(lastPos, bin_cache[u]);
- //sort positive values using normal spreadsort
- else
- spreadsort_rec<RandomAccessIter, Div_type, Right_shift, Size_type,
- float_log_mean_bin_size, float_log_min_split_count,
- float_log_finishing_count>
- (lastPos, bin_cache[u], bin_cache, cache_end, bin_sizes, rshift);
- }
- }
-
- template <class RandomAccessIter, class Div_type, class Right_shift,
- class Compare, class Size_type>
- inline void
- float_sort_rec(RandomAccessIter first, RandomAccessIter last,
- std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset,
- size_t *bin_sizes, Right_shift rshift, Compare comp)
- {
- Div_type max, min;
- if (is_sorted_or_find_extremes(first, last, max, min, rshift, comp))
- return;
- unsigned log_divisor = get_log_divisor<float_log_mean_bin_size>(
- last - first, rough_log_2_size(Size_type(max - min)));
- Div_type div_min = min >> log_divisor;
- Div_type div_max = max >> log_divisor;
- unsigned bin_count = unsigned(div_max - div_min) + 1;
- unsigned cache_end;
- RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset,
- cache_end, bin_count);
-
- //Calculating the size of each bin
- for (RandomAccessIter current = first; current != last;)
- bin_sizes[unsigned(rshift(*(current++), log_divisor) - div_min)]++;
- //The index of the first positive bin
- unsigned first_positive =
- (div_min < 0) ? static_cast<unsigned>(-div_min) : 0;
- //Resetting if all bins are negative
- if (cache_offset + first_positive > cache_end)
- first_positive = cache_end - cache_offset;
- //Reversing the order of the negative bins
- //Note that because of the negative/positive ordering direction flip
- //We can not depend upon bin order and positions matching up
- //so bin_sizes must be reused to contain the end of the bin
- if (first_positive > 0) {
- bins[first_positive - 1] = first;
- for (int ii = first_positive - 2; ii >= 0; --ii) {
- bins[ii] = first + bin_sizes[ii + 1];
- bin_sizes[ii] += bin_sizes[ii + 1];
- }
- //Handling positives following negatives
- if (static_cast<unsigned>(first_positive) < bin_count) {
- bins[first_positive] = first + bin_sizes[0];
- bin_sizes[first_positive] += bin_sizes[0];
- }
- }
- else
- bins[0] = first;
- for (unsigned u = first_positive; u < bin_count - 1; u++) {
- bins[u + 1] = first + bin_sizes[u];
- bin_sizes[u + 1] += bin_sizes[u];
- }
-
- //Swap into place
- RandomAccessIter next_bin_start = first;
- for (unsigned u = 0; u < bin_count; ++u) {
- next_bin_start = first + bin_sizes[u];
- inner_swap_loop<RandomAccessIter, Div_type, Right_shift>
- (bins, next_bin_start, u, rshift, log_divisor, div_min);
- }
-
- //Return if we've completed bucketsorting
- if (!log_divisor)
- return;
-
- //Handling negative values first
- size_t max_count = get_min_count<float_log_mean_bin_size,
- float_log_min_split_count,
- float_log_finishing_count>(log_divisor);
- RandomAccessIter lastPos = first;
- for (int ii = cache_offset + first_positive - 1;
- ii >= static_cast<int>(cache_offset);
- lastPos = bin_cache[ii--]) {
- size_t count = bin_cache[ii] - lastPos;
- if (count < 2)
- continue;
- if (count < max_count)
- std::sort(lastPos, bin_cache[ii], comp);
- //sort negative values using reversed-bin spreadsort
- else
- negative_float_sort_rec<RandomAccessIter, Div_type, Right_shift,
- Compare, Size_type>(lastPos, bin_cache[ii],
- bin_cache, cache_end,
- bin_sizes, rshift, comp);
- }
-
- for (unsigned u = cache_offset + first_positive; u < cache_end;
- lastPos = bin_cache[u], ++u) {
- size_t count = bin_cache[u] - lastPos;
- if (count < 2)
- continue;
- if (count < max_count)
- std::sort(lastPos, bin_cache[u], comp);
- //sort positive values using normal spreadsort
- else
- spreadsort_rec<RandomAccessIter, Div_type, Right_shift, Compare,
- Size_type, float_log_mean_bin_size,
- float_log_min_split_count, float_log_finishing_count>
- (lastPos, bin_cache[u], bin_cache, cache_end, bin_sizes, rshift, comp);
- }
- }
-
- //Checking whether the value type is a float, and trying a 32-bit integer
- template <class RandomAccessIter>
- inline typename boost::enable_if_c< sizeof(boost::uint32_t) ==
- sizeof(typename std::iterator_traits<RandomAccessIter>::value_type)
- && std::numeric_limits<typename
- std::iterator_traits<RandomAccessIter>::value_type>::is_iec559,
- void >::type
- float_sort(RandomAccessIter first, RandomAccessIter last)
- {
- size_t bin_sizes[1 << max_finishing_splits];
- std::vector<RandomAccessIter> bin_cache;
- float_sort_rec<RandomAccessIter, boost::int32_t, boost::uint32_t>
- (first, last, bin_cache, 0, bin_sizes);
- }
-
- //Checking whether the value type is a double, and using a 64-bit integer
- template <class RandomAccessIter>
- inline typename boost::enable_if_c< sizeof(boost::uint64_t) ==
- sizeof(typename std::iterator_traits<RandomAccessIter>::value_type)
- && std::numeric_limits<typename
- std::iterator_traits<RandomAccessIter>::value_type>::is_iec559,
- void >::type
- float_sort(RandomAccessIter first, RandomAccessIter last)
- {
- size_t bin_sizes[1 << max_finishing_splits];
- std::vector<RandomAccessIter> bin_cache;
- float_sort_rec<RandomAccessIter, boost::int64_t, boost::uint64_t>
- (first, last, bin_cache, 0, bin_sizes);
- }
-
- template <class RandomAccessIter>
- inline typename boost::disable_if_c< (sizeof(boost::uint64_t) ==
- sizeof(typename std::iterator_traits<RandomAccessIter>::value_type)
- || sizeof(boost::uint32_t) ==
- sizeof(typename std::iterator_traits<RandomAccessIter>::value_type))
- && std::numeric_limits<typename
- std::iterator_traits<RandomAccessIter>::value_type>::is_iec559,
- void >::type
- float_sort(RandomAccessIter first, RandomAccessIter last)
- {
- BOOST_STATIC_WARNING(!(sizeof(boost::uint64_t) ==
- sizeof(typename std::iterator_traits<RandomAccessIter>::value_type)
- || sizeof(boost::uint32_t) ==
- sizeof(typename std::iterator_traits<RandomAccessIter>::value_type))
- || !std::numeric_limits<typename
- std::iterator_traits<RandomAccessIter>::value_type>::is_iec559);
- std::sort(first, last);
- }
-
- //These approaches require the user to do the typecast
- //with rshift but default comparision
- template <class RandomAccessIter, class Div_type, class Right_shift>
- inline typename boost::enable_if_c< sizeof(size_t) >= sizeof(Div_type),
- void >::type
- float_sort(RandomAccessIter first, RandomAccessIter last, Div_type,
- Right_shift rshift)
- {
- size_t bin_sizes[1 << max_finishing_splits];
- std::vector<RandomAccessIter> bin_cache;
- float_sort_rec<RandomAccessIter, Div_type, Right_shift, size_t>
- (first, last, bin_cache, 0, bin_sizes, rshift);
- }
-
- //maximum integer size with rshift but default comparision
- template <class RandomAccessIter, class Div_type, class Right_shift>
- inline typename boost::enable_if_c< sizeof(size_t) < sizeof(Div_type)
- && sizeof(boost::uintmax_t) >= sizeof(Div_type), void >::type
- float_sort(RandomAccessIter first, RandomAccessIter last, Div_type,
- Right_shift rshift)
- {
- size_t bin_sizes[1 << max_finishing_splits];
- std::vector<RandomAccessIter> bin_cache;
- float_sort_rec<RandomAccessIter, Div_type, Right_shift, boost::uintmax_t>
- (first, last, bin_cache, 0, bin_sizes, rshift);
- }
-
- //sizeof(Div_type) doesn't match, so use std::sort
- template <class RandomAccessIter, class Div_type, class Right_shift>
- inline typename boost::disable_if_c< sizeof(boost::uintmax_t) >=
- sizeof(Div_type), void >::type
- float_sort(RandomAccessIter first, RandomAccessIter last, Div_type,
- Right_shift rshift)
- {
- BOOST_STATIC_WARNING(sizeof(boost::uintmax_t) >= sizeof(Div_type));
- std::sort(first, last);
- }
-
- //specialized comparison
- template <class RandomAccessIter, class Div_type, class Right_shift,
- class Compare>
- inline typename boost::enable_if_c< sizeof(size_t) >= sizeof(Div_type),
- void >::type
- float_sort(RandomAccessIter first, RandomAccessIter last, Div_type,
- Right_shift rshift, Compare comp)
- {
- size_t bin_sizes[1 << max_finishing_splits];
- std::vector<RandomAccessIter> bin_cache;
- float_sort_rec<RandomAccessIter, Div_type, Right_shift, Compare,
- size_t>
- (first, last, bin_cache, 0, bin_sizes, rshift, comp);
- }
-
- //max-sized integer with specialized comparison
- template <class RandomAccessIter, class Div_type, class Right_shift,
- class Compare>
- inline typename boost::enable_if_c< sizeof(size_t) < sizeof(Div_type)
- && sizeof(boost::uintmax_t) >= sizeof(Div_type), void >::type
- float_sort(RandomAccessIter first, RandomAccessIter last, Div_type,
- Right_shift rshift, Compare comp)
- {
- size_t bin_sizes[1 << max_finishing_splits];
- std::vector<RandomAccessIter> bin_cache;
- float_sort_rec<RandomAccessIter, Div_type, Right_shift, Compare,
- boost::uintmax_t>
- (first, last, bin_cache, 0, bin_sizes, rshift, comp);
- }
-
- //sizeof(Div_type) doesn't match, so use std::sort
- template <class RandomAccessIter, class Div_type, class Right_shift,
- class Compare>
- inline typename boost::disable_if_c< sizeof(boost::uintmax_t) >=
- sizeof(Div_type), void >::type
- float_sort(RandomAccessIter first, RandomAccessIter last, Div_type,
- Right_shift rshift, Compare comp)
- {
- BOOST_STATIC_WARNING(sizeof(boost::uintmax_t) >= sizeof(Div_type));
- std::sort(first, last, comp);
- }
- }
-}
-}
-}
-
-#endif
+// Details for templated Spreadsort-based float_sort. + +// Copyright Steven J. Ross 2001 - 2014. +// Distributed under the Boost Software License, Version 1.0. +// (See accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) + +// See http://www.boost.org/libs/sort for library home page. + +/* +Some improvements suggested by: +Phil Endecott and Frank Gennari +float_mem_cast fix provided by: +Scott McMurray +*/ + +#ifndef BOOST_SORT_SPREADSORT_DETAIL_FLOAT_SORT_HPP +#define BOOST_SORT_SPREADSORT_DETAIL_FLOAT_SORT_HPP +#include <algorithm> +#include <vector> +#include <limits> +#include <functional> +#include <boost/static_assert.hpp> +#include <boost/serialization/static_warning.hpp> +#include <boost/utility/enable_if.hpp> +#include <boost/sort/spreadsort/detail/constants.hpp> +#include <boost/sort/spreadsort/detail/integer_sort.hpp> +#include <boost/sort/spreadsort/detail/spreadsort_common.hpp> +#include <boost/cstdint.hpp> + +namespace boost { +namespace sort { +namespace spreadsort { + namespace detail { + //Casts a RandomAccessIter to the specified integer type + template<class Cast_type, class RandomAccessIter> + inline Cast_type + cast_float_iter(const RandomAccessIter & floatiter) + { + typedef typename std::iterator_traits<RandomAccessIter>::value_type + Data_type; + //Only cast IEEE floating-point numbers, and only to same-sized integers + BOOST_STATIC_ASSERT(sizeof(Cast_type) == sizeof(Data_type)); + BOOST_STATIC_ASSERT(std::numeric_limits<Data_type>::is_iec559); + BOOST_STATIC_ASSERT(std::numeric_limits<Cast_type>::is_integer); + Cast_type result; + std::memcpy(&result, &(*floatiter), sizeof(Data_type)); + return result; + } + + // Return true if the list is sorted. Otherwise, find the minimum and + // maximum. Values are Right_shifted 0 bits before comparison. + template <class RandomAccessIter, class Div_type, class Right_shift> + inline bool + is_sorted_or_find_extremes(RandomAccessIter current, RandomAccessIter last, + Div_type & max, Div_type & min, Right_shift rshift) + { + min = max = rshift(*current, 0); + RandomAccessIter prev = current; + bool sorted = true; + while (++current < last) { + Div_type value = rshift(*current, 0); + sorted &= *current >= *prev; + prev = current; + if (max < value) + max = value; + else if (value < min) + min = value; + } + return sorted; + } + + // Return true if the list is sorted. Otherwise, find the minimum and + // maximum. Uses comp to check if the data is already sorted. + template <class RandomAccessIter, class Div_type, class Right_shift, + class Compare> + inline bool + is_sorted_or_find_extremes(RandomAccessIter current, RandomAccessIter last, + Div_type & max, Div_type & min, + Right_shift rshift, Compare comp) + { + min = max = rshift(*current, 0); + RandomAccessIter prev = current; + bool sorted = true; + while (++current < last) { + Div_type value = rshift(*current, 0); + sorted &= !comp(*current, *prev); + prev = current; + if (max < value) + max = value; + else if (value < min) + min = value; + } + return sorted; + } + + //Specialized swap loops for floating-point casting + template <class RandomAccessIter, class Div_type> + inline void inner_float_swap_loop(RandomAccessIter * bins, + const RandomAccessIter & nextbinstart, unsigned ii + , const unsigned log_divisor, const Div_type div_min) + { + RandomAccessIter * local_bin = bins + ii; + for (RandomAccessIter current = *local_bin; current < nextbinstart; + ++current) { + for (RandomAccessIter * target_bin = + (bins + ((cast_float_iter<Div_type, RandomAccessIter>(current) >> + log_divisor) - div_min)); target_bin != local_bin; + target_bin = bins + ((cast_float_iter<Div_type, RandomAccessIter> + (current) >> log_divisor) - div_min)) { + typename std::iterator_traits<RandomAccessIter>::value_type tmp; + RandomAccessIter b = (*target_bin)++; + RandomAccessIter * b_bin = bins + ((cast_float_iter<Div_type, + RandomAccessIter>(b) >> log_divisor) - div_min); + //Three-way swap; if the item to be swapped doesn't belong in the + //current bin, swap it to where it belongs + if (b_bin != local_bin) { + RandomAccessIter c = (*b_bin)++; + tmp = *c; + *c = *b; + } + else + tmp = *b; + *b = *current; + *current = tmp; + } + } + *local_bin = nextbinstart; + } + + template <class RandomAccessIter, class Div_type> + inline void float_swap_loop(RandomAccessIter * bins, + RandomAccessIter & nextbinstart, unsigned ii, + const size_t *bin_sizes, + const unsigned log_divisor, const Div_type div_min) + { + nextbinstart += bin_sizes[ii]; + inner_float_swap_loop<RandomAccessIter, Div_type> + (bins, nextbinstart, ii, log_divisor, div_min); + } + + // Return true if the list is sorted. Otherwise, find the minimum and + // maximum. Values are cast to Cast_type before comparison. + template <class RandomAccessIter, class Cast_type> + inline bool + is_sorted_or_find_extremes(RandomAccessIter current, RandomAccessIter last, + Cast_type & max, Cast_type & min) + { + min = max = cast_float_iter<Cast_type, RandomAccessIter>(current); + RandomAccessIter prev = current; + bool sorted = true; + while (++current < last) { + Cast_type value = cast_float_iter<Cast_type, RandomAccessIter>(current); + sorted &= *current >= *prev; + prev = current; + if (max < value) + max = value; + else if (value < min) + min = value; + } + return sorted; + } + + //Special-case sorting of positive floats with casting + template <class RandomAccessIter, class Div_type, class Size_type> + inline void + positive_float_sort_rec(RandomAccessIter first, RandomAccessIter last, + std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset + , size_t *bin_sizes) + { + Div_type max, min; + if (is_sorted_or_find_extremes<RandomAccessIter, Div_type>(first, last, + max, min)) + return; + unsigned log_divisor = get_log_divisor<float_log_mean_bin_size>( + last - first, rough_log_2_size(Size_type(max - min))); + Div_type div_min = min >> log_divisor; + Div_type div_max = max >> log_divisor; + unsigned bin_count = unsigned(div_max - div_min) + 1; + unsigned cache_end; + RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset, + cache_end, bin_count); + + //Calculating the size of each bin + for (RandomAccessIter current = first; current != last;) + bin_sizes[unsigned((cast_float_iter<Div_type, RandomAccessIter>( + current++) >> log_divisor) - div_min)]++; + bins[0] = first; + for (unsigned u = 0; u < bin_count - 1; u++) + bins[u + 1] = bins[u] + bin_sizes[u]; + + + //Swap into place + RandomAccessIter nextbinstart = first; + for (unsigned u = 0; u < bin_count - 1; ++u) + float_swap_loop<RandomAccessIter, Div_type> + (bins, nextbinstart, u, bin_sizes, log_divisor, div_min); + bins[bin_count - 1] = last; + + //Return if we've completed bucketsorting + if (!log_divisor) + return; + + //Recursing + size_t max_count = get_min_count<float_log_mean_bin_size, + float_log_min_split_count, + float_log_finishing_count>(log_divisor); + RandomAccessIter lastPos = first; + for (unsigned u = cache_offset; u < cache_end; lastPos = bin_cache[u], + ++u) { + size_t count = bin_cache[u] - lastPos; + if (count < 2) + continue; + if (count < max_count) + std::sort(lastPos, bin_cache[u]); + else + positive_float_sort_rec<RandomAccessIter, Div_type, Size_type> + (lastPos, bin_cache[u], bin_cache, cache_end, bin_sizes); + } + } + + //Sorting negative floats + //Bins are iterated in reverse because max_neg_float = min_neg_int + template <class RandomAccessIter, class Div_type, class Size_type> + inline void + negative_float_sort_rec(RandomAccessIter first, RandomAccessIter last, + std::vector<RandomAccessIter> &bin_cache, + unsigned cache_offset, size_t *bin_sizes) + { + Div_type max, min; + if (is_sorted_or_find_extremes<RandomAccessIter, Div_type>(first, last, + max, min)) + return; + + unsigned log_divisor = get_log_divisor<float_log_mean_bin_size>( + last - first, rough_log_2_size(Size_type(max - min))); + Div_type div_min = min >> log_divisor; + Div_type div_max = max >> log_divisor; + unsigned bin_count = unsigned(div_max - div_min) + 1; + unsigned cache_end; + RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset, + cache_end, bin_count); + + //Calculating the size of each bin + for (RandomAccessIter current = first; current != last;) + bin_sizes[unsigned((cast_float_iter<Div_type, RandomAccessIter>( + current++) >> log_divisor) - div_min)]++; + bins[bin_count - 1] = first; + for (int ii = bin_count - 2; ii >= 0; --ii) + bins[ii] = bins[ii + 1] + bin_sizes[ii + 1]; + + //Swap into place + RandomAccessIter nextbinstart = first; + //The last bin will always have the correct elements in it + for (int ii = bin_count - 1; ii > 0; --ii) + float_swap_loop<RandomAccessIter, Div_type> + (bins, nextbinstart, ii, bin_sizes, log_divisor, div_min); + //Update the end position because we don't process the last bin + bin_cache[cache_offset] = last; + + //Return if we've completed bucketsorting + if (!log_divisor) + return; + + //Recursing + size_t max_count = get_min_count<float_log_mean_bin_size, + float_log_min_split_count, + float_log_finishing_count>(log_divisor); + RandomAccessIter lastPos = first; + for (int ii = cache_end - 1; ii >= static_cast<int>(cache_offset); + lastPos = bin_cache[ii], --ii) { + size_t count = bin_cache[ii] - lastPos; + if (count < 2) + continue; + if (count < max_count) + std::sort(lastPos, bin_cache[ii]); + else + negative_float_sort_rec<RandomAccessIter, Div_type, Size_type> + (lastPos, bin_cache[ii], bin_cache, cache_end, bin_sizes); + } + } + + //Sorting negative floats + //Bins are iterated in reverse order because max_neg_float = min_neg_int + template <class RandomAccessIter, class Div_type, class Right_shift, + class Size_type> + inline void + negative_float_sort_rec(RandomAccessIter first, RandomAccessIter last, + std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset + , size_t *bin_sizes, Right_shift rshift) + { + Div_type max, min; + if (is_sorted_or_find_extremes(first, last, max, min, rshift)) + return; + unsigned log_divisor = get_log_divisor<float_log_mean_bin_size>( + last - first, rough_log_2_size(Size_type(max - min))); + Div_type div_min = min >> log_divisor; + Div_type div_max = max >> log_divisor; + unsigned bin_count = unsigned(div_max - div_min) + 1; + unsigned cache_end; + RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset, + cache_end, bin_count); + + //Calculating the size of each bin + for (RandomAccessIter current = first; current != last;) + bin_sizes[unsigned(rshift(*(current++), log_divisor) - div_min)]++; + bins[bin_count - 1] = first; + for (int ii = bin_count - 2; ii >= 0; --ii) + bins[ii] = bins[ii + 1] + bin_sizes[ii + 1]; + + //Swap into place + RandomAccessIter nextbinstart = first; + //The last bin will always have the correct elements in it + for (int ii = bin_count - 1; ii > 0; --ii) + swap_loop<RandomAccessIter, Div_type, Right_shift> + (bins, nextbinstart, ii, rshift, bin_sizes, log_divisor, div_min); + //Update the end position of the unprocessed last bin + bin_cache[cache_offset] = last; + + //Return if we've completed bucketsorting + if (!log_divisor) + return; + + //Recursing + size_t max_count = get_min_count<float_log_mean_bin_size, + float_log_min_split_count, + float_log_finishing_count>(log_divisor); + RandomAccessIter lastPos = first; + for (int ii = cache_end - 1; ii >= static_cast<int>(cache_offset); + lastPos = bin_cache[ii], --ii) { + size_t count = bin_cache[ii] - lastPos; + if (count < 2) + continue; + if (count < max_count) + std::sort(lastPos, bin_cache[ii]); + else + negative_float_sort_rec<RandomAccessIter, Div_type, Right_shift, + Size_type> + (lastPos, bin_cache[ii], bin_cache, cache_end, bin_sizes, rshift); + } + } + + template <class RandomAccessIter, class Div_type, class Right_shift, + class Compare, class Size_type> + inline void + negative_float_sort_rec(RandomAccessIter first, RandomAccessIter last, + std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset, + size_t *bin_sizes, Right_shift rshift, Compare comp) + { + Div_type max, min; + if (is_sorted_or_find_extremes(first, last, max, min, rshift, comp)) + return; + unsigned log_divisor = get_log_divisor<float_log_mean_bin_size>( + last - first, rough_log_2_size(Size_type(max - min))); + Div_type div_min = min >> log_divisor; + Div_type div_max = max >> log_divisor; + unsigned bin_count = unsigned(div_max - div_min) + 1; + unsigned cache_end; + RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset, + cache_end, bin_count); + + //Calculating the size of each bin + for (RandomAccessIter current = first; current != last;) + bin_sizes[unsigned(rshift(*(current++), log_divisor) - div_min)]++; + bins[bin_count - 1] = first; + for (int ii = bin_count - 2; ii >= 0; --ii) + bins[ii] = bins[ii + 1] + bin_sizes[ii + 1]; + + //Swap into place + RandomAccessIter nextbinstart = first; + //The last bin will always have the correct elements in it + for (int ii = bin_count - 1; ii > 0; --ii) + swap_loop<RandomAccessIter, Div_type, Right_shift> + (bins, nextbinstart, ii, rshift, bin_sizes, log_divisor, div_min); + //Update the end position of the unprocessed last bin + bin_cache[cache_offset] = last; + + //Return if we've completed bucketsorting + if (!log_divisor) + return; + + //Recursing + size_t max_count = get_min_count<float_log_mean_bin_size, + float_log_min_split_count, + float_log_finishing_count>(log_divisor); + RandomAccessIter lastPos = first; + for (int ii = cache_end - 1; ii >= static_cast<int>(cache_offset); + lastPos = bin_cache[ii], --ii) { + size_t count = bin_cache[ii] - lastPos; + if (count < 2) + continue; + if (count < max_count) + std::sort(lastPos, bin_cache[ii], comp); + else + negative_float_sort_rec<RandomAccessIter, Div_type, Right_shift, + Compare, Size_type>(lastPos, bin_cache[ii], + bin_cache, cache_end, + bin_sizes, rshift, comp); + } + } + + //Casting special-case for floating-point sorting + template <class RandomAccessIter, class Div_type, class Size_type> + inline void + float_sort_rec(RandomAccessIter first, RandomAccessIter last, + std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset + , size_t *bin_sizes) + { + Div_type max, min; + if (is_sorted_or_find_extremes<RandomAccessIter, Div_type>(first, last, + max, min)) + return; + unsigned log_divisor = get_log_divisor<float_log_mean_bin_size>( + last - first, rough_log_2_size(Size_type(max - min))); + Div_type div_min = min >> log_divisor; + Div_type div_max = max >> log_divisor; + unsigned bin_count = unsigned(div_max - div_min) + 1; + unsigned cache_end; + RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset, + cache_end, bin_count); + + //Calculating the size of each bin + for (RandomAccessIter current = first; current != last;) + bin_sizes[unsigned((cast_float_iter<Div_type, RandomAccessIter>( + current++) >> log_divisor) - div_min)]++; + //The index of the first positive bin + //Must be divided small enough to fit into an integer + unsigned first_positive = (div_min < 0) ? unsigned(-div_min) : 0; + //Resetting if all bins are negative + if (cache_offset + first_positive > cache_end) + first_positive = cache_end - cache_offset; + //Reversing the order of the negative bins + //Note that because of the negative/positive ordering direction flip + //We can not depend upon bin order and positions matching up + //so bin_sizes must be reused to contain the end of the bin + if (first_positive > 0) { + bins[first_positive - 1] = first; + for (int ii = first_positive - 2; ii >= 0; --ii) { + bins[ii] = first + bin_sizes[ii + 1]; + bin_sizes[ii] += bin_sizes[ii + 1]; + } + //Handling positives following negatives + if (first_positive < bin_count) { + bins[first_positive] = first + bin_sizes[0]; + bin_sizes[first_positive] += bin_sizes[0]; + } + } + else + bins[0] = first; + for (unsigned u = first_positive; u < bin_count - 1; u++) { + bins[u + 1] = first + bin_sizes[u]; + bin_sizes[u + 1] += bin_sizes[u]; + } + + //Swap into place + RandomAccessIter nextbinstart = first; + for (unsigned u = 0; u < bin_count; ++u) { + nextbinstart = first + bin_sizes[u]; + inner_float_swap_loop<RandomAccessIter, Div_type> + (bins, nextbinstart, u, log_divisor, div_min); + } + + if (!log_divisor) + return; + + //Handling negative values first + size_t max_count = get_min_count<float_log_mean_bin_size, + float_log_min_split_count, + float_log_finishing_count>(log_divisor); + RandomAccessIter lastPos = first; + for (int ii = cache_offset + first_positive - 1; + ii >= static_cast<int>(cache_offset); + lastPos = bin_cache[ii--]) { + size_t count = bin_cache[ii] - lastPos; + if (count < 2) + continue; + if (count < max_count) + std::sort(lastPos, bin_cache[ii]); + //sort negative values using reversed-bin spreadsort + else + negative_float_sort_rec<RandomAccessIter, Div_type, Size_type> + (lastPos, bin_cache[ii], bin_cache, cache_end, bin_sizes); + } + + for (unsigned u = cache_offset + first_positive; u < cache_end; + lastPos = bin_cache[u], ++u) { + size_t count = bin_cache[u] - lastPos; + if (count < 2) + continue; + if (count < max_count) + std::sort(lastPos, bin_cache[u]); + //sort positive values using normal spreadsort + else + positive_float_sort_rec<RandomAccessIter, Div_type, Size_type> + (lastPos, bin_cache[u], bin_cache, cache_end, bin_sizes); + } + } + + //Functor implementation for recursive sorting + template <class RandomAccessIter, class Div_type, class Right_shift + , class Size_type> + inline void + float_sort_rec(RandomAccessIter first, RandomAccessIter last, + std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset + , size_t *bin_sizes, Right_shift rshift) + { + Div_type max, min; + if (is_sorted_or_find_extremes(first, last, max, min, rshift)) + return; + unsigned log_divisor = get_log_divisor<float_log_mean_bin_size>( + last - first, rough_log_2_size(Size_type(max - min))); + Div_type div_min = min >> log_divisor; + Div_type div_max = max >> log_divisor; + unsigned bin_count = unsigned(div_max - div_min) + 1; + unsigned cache_end; + RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset, + cache_end, bin_count); + + //Calculating the size of each bin + for (RandomAccessIter current = first; current != last;) + bin_sizes[unsigned(rshift(*(current++), log_divisor) - div_min)]++; + //The index of the first positive bin + unsigned first_positive = (div_min < 0) ? unsigned(-div_min) : 0; + //Resetting if all bins are negative + if (cache_offset + first_positive > cache_end) + first_positive = cache_end - cache_offset; + //Reversing the order of the negative bins + //Note that because of the negative/positive ordering direction flip + //We can not depend upon bin order and positions matching up + //so bin_sizes must be reused to contain the end of the bin + if (first_positive > 0) { + bins[first_positive - 1] = first; + for (int ii = first_positive - 2; ii >= 0; --ii) { + bins[ii] = first + bin_sizes[ii + 1]; + bin_sizes[ii] += bin_sizes[ii + 1]; + } + //Handling positives following negatives + if (static_cast<unsigned>(first_positive) < bin_count) { + bins[first_positive] = first + bin_sizes[0]; + bin_sizes[first_positive] += bin_sizes[0]; + } + } + else + bins[0] = first; + for (unsigned u = first_positive; u < bin_count - 1; u++) { + bins[u + 1] = first + bin_sizes[u]; + bin_sizes[u + 1] += bin_sizes[u]; + } + + //Swap into place + RandomAccessIter next_bin_start = first; + for (unsigned u = 0; u < bin_count; ++u) { + next_bin_start = first + bin_sizes[u]; + inner_swap_loop<RandomAccessIter, Div_type, Right_shift> + (bins, next_bin_start, u, rshift, log_divisor, div_min); + } + + //Return if we've completed bucketsorting + if (!log_divisor) + return; + + //Handling negative values first + size_t max_count = get_min_count<float_log_mean_bin_size, + float_log_min_split_count, + float_log_finishing_count>(log_divisor); + RandomAccessIter lastPos = first; + for (int ii = cache_offset + first_positive - 1; + ii >= static_cast<int>(cache_offset); + lastPos = bin_cache[ii--]) { + size_t count = bin_cache[ii] - lastPos; + if (count < 2) + continue; + if (count < max_count) + std::sort(lastPos, bin_cache[ii]); + //sort negative values using reversed-bin spreadsort + else + negative_float_sort_rec<RandomAccessIter, Div_type, + Right_shift, Size_type>(lastPos, bin_cache[ii], bin_cache, + cache_end, bin_sizes, rshift); + } + + for (unsigned u = cache_offset + first_positive; u < cache_end; + lastPos = bin_cache[u], ++u) { + size_t count = bin_cache[u] - lastPos; + if (count < 2) + continue; + if (count < max_count) + std::sort(lastPos, bin_cache[u]); + //sort positive values using normal spreadsort + else + spreadsort_rec<RandomAccessIter, Div_type, Right_shift, Size_type, + float_log_mean_bin_size, float_log_min_split_count, + float_log_finishing_count> + (lastPos, bin_cache[u], bin_cache, cache_end, bin_sizes, rshift); + } + } + + template <class RandomAccessIter, class Div_type, class Right_shift, + class Compare, class Size_type> + inline void + float_sort_rec(RandomAccessIter first, RandomAccessIter last, + std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset, + size_t *bin_sizes, Right_shift rshift, Compare comp) + { + Div_type max, min; + if (is_sorted_or_find_extremes(first, last, max, min, rshift, comp)) + return; + unsigned log_divisor = get_log_divisor<float_log_mean_bin_size>( + last - first, rough_log_2_size(Size_type(max - min))); + Div_type div_min = min >> log_divisor; + Div_type div_max = max >> log_divisor; + unsigned bin_count = unsigned(div_max - div_min) + 1; + unsigned cache_end; + RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset, + cache_end, bin_count); + + //Calculating the size of each bin + for (RandomAccessIter current = first; current != last;) + bin_sizes[unsigned(rshift(*(current++), log_divisor) - div_min)]++; + //The index of the first positive bin + unsigned first_positive = + (div_min < 0) ? static_cast<unsigned>(-div_min) : 0; + //Resetting if all bins are negative + if (cache_offset + first_positive > cache_end) + first_positive = cache_end - cache_offset; + //Reversing the order of the negative bins + //Note that because of the negative/positive ordering direction flip + //We can not depend upon bin order and positions matching up + //so bin_sizes must be reused to contain the end of the bin + if (first_positive > 0) { + bins[first_positive - 1] = first; + for (int ii = first_positive - 2; ii >= 0; --ii) { + bins[ii] = first + bin_sizes[ii + 1]; + bin_sizes[ii] += bin_sizes[ii + 1]; + } + //Handling positives following negatives + if (static_cast<unsigned>(first_positive) < bin_count) { + bins[first_positive] = first + bin_sizes[0]; + bin_sizes[first_positive] += bin_sizes[0]; + } + } + else + bins[0] = first; + for (unsigned u = first_positive; u < bin_count - 1; u++) { + bins[u + 1] = first + bin_sizes[u]; + bin_sizes[u + 1] += bin_sizes[u]; + } + + //Swap into place + RandomAccessIter next_bin_start = first; + for (unsigned u = 0; u < bin_count; ++u) { + next_bin_start = first + bin_sizes[u]; + inner_swap_loop<RandomAccessIter, Div_type, Right_shift> + (bins, next_bin_start, u, rshift, log_divisor, div_min); + } + + //Return if we've completed bucketsorting + if (!log_divisor) + return; + + //Handling negative values first + size_t max_count = get_min_count<float_log_mean_bin_size, + float_log_min_split_count, + float_log_finishing_count>(log_divisor); + RandomAccessIter lastPos = first; + for (int ii = cache_offset + first_positive - 1; + ii >= static_cast<int>(cache_offset); + lastPos = bin_cache[ii--]) { + size_t count = bin_cache[ii] - lastPos; + if (count < 2) + continue; + if (count < max_count) + std::sort(lastPos, bin_cache[ii], comp); + //sort negative values using reversed-bin spreadsort + else + negative_float_sort_rec<RandomAccessIter, Div_type, Right_shift, + Compare, Size_type>(lastPos, bin_cache[ii], + bin_cache, cache_end, + bin_sizes, rshift, comp); + } + + for (unsigned u = cache_offset + first_positive; u < cache_end; + lastPos = bin_cache[u], ++u) { + size_t count = bin_cache[u] - lastPos; + if (count < 2) + continue; + if (count < max_count) + std::sort(lastPos, bin_cache[u], comp); + //sort positive values using normal spreadsort + else + spreadsort_rec<RandomAccessIter, Div_type, Right_shift, Compare, + Size_type, float_log_mean_bin_size, + float_log_min_split_count, float_log_finishing_count> + (lastPos, bin_cache[u], bin_cache, cache_end, bin_sizes, rshift, comp); + } + } + + //Checking whether the value type is a float, and trying a 32-bit integer + template <class RandomAccessIter> + inline typename boost::enable_if_c< sizeof(boost::uint32_t) == + sizeof(typename std::iterator_traits<RandomAccessIter>::value_type) + && std::numeric_limits<typename + std::iterator_traits<RandomAccessIter>::value_type>::is_iec559, + void >::type + float_sort(RandomAccessIter first, RandomAccessIter last) + { + size_t bin_sizes[1 << max_finishing_splits]; + std::vector<RandomAccessIter> bin_cache; + float_sort_rec<RandomAccessIter, boost::int32_t, boost::uint32_t> + (first, last, bin_cache, 0, bin_sizes); + } + + //Checking whether the value type is a double, and using a 64-bit integer + template <class RandomAccessIter> + inline typename boost::enable_if_c< sizeof(boost::uint64_t) == + sizeof(typename std::iterator_traits<RandomAccessIter>::value_type) + && std::numeric_limits<typename + std::iterator_traits<RandomAccessIter>::value_type>::is_iec559, + void >::type + float_sort(RandomAccessIter first, RandomAccessIter last) + { + size_t bin_sizes[1 << max_finishing_splits]; + std::vector<RandomAccessIter> bin_cache; + float_sort_rec<RandomAccessIter, boost::int64_t, boost::uint64_t> + (first, last, bin_cache, 0, bin_sizes); + } + + template <class RandomAccessIter> + inline typename boost::disable_if_c< (sizeof(boost::uint64_t) == + sizeof(typename std::iterator_traits<RandomAccessIter>::value_type) + || sizeof(boost::uint32_t) == + sizeof(typename std::iterator_traits<RandomAccessIter>::value_type)) + && std::numeric_limits<typename + std::iterator_traits<RandomAccessIter>::value_type>::is_iec559, + void >::type + float_sort(RandomAccessIter first, RandomAccessIter last) + { + BOOST_STATIC_WARNING(!(sizeof(boost::uint64_t) == + sizeof(typename std::iterator_traits<RandomAccessIter>::value_type) + || sizeof(boost::uint32_t) == + sizeof(typename std::iterator_traits<RandomAccessIter>::value_type)) + || !std::numeric_limits<typename + std::iterator_traits<RandomAccessIter>::value_type>::is_iec559); + std::sort(first, last); + } + + //These approaches require the user to do the typecast + //with rshift but default comparision + template <class RandomAccessIter, class Div_type, class Right_shift> + inline typename boost::enable_if_c< sizeof(size_t) >= sizeof(Div_type), + void >::type + float_sort(RandomAccessIter first, RandomAccessIter last, Div_type, + Right_shift rshift) + { + size_t bin_sizes[1 << max_finishing_splits]; + std::vector<RandomAccessIter> bin_cache; + float_sort_rec<RandomAccessIter, Div_type, Right_shift, size_t> + (first, last, bin_cache, 0, bin_sizes, rshift); + } + + //maximum integer size with rshift but default comparision + template <class RandomAccessIter, class Div_type, class Right_shift> + inline typename boost::enable_if_c< sizeof(size_t) < sizeof(Div_type) + && sizeof(boost::uintmax_t) >= sizeof(Div_type), void >::type + float_sort(RandomAccessIter first, RandomAccessIter last, Div_type, + Right_shift rshift) + { + size_t bin_sizes[1 << max_finishing_splits]; + std::vector<RandomAccessIter> bin_cache; + float_sort_rec<RandomAccessIter, Div_type, Right_shift, boost::uintmax_t> + (first, last, bin_cache, 0, bin_sizes, rshift); + } + + //sizeof(Div_type) doesn't match, so use std::sort + template <class RandomAccessIter, class Div_type, class Right_shift> + inline typename boost::disable_if_c< sizeof(boost::uintmax_t) >= + sizeof(Div_type), void >::type + float_sort(RandomAccessIter first, RandomAccessIter last, Div_type, + Right_shift rshift) + { + BOOST_STATIC_WARNING(sizeof(boost::uintmax_t) >= sizeof(Div_type)); + std::sort(first, last); + } + + //specialized comparison + template <class RandomAccessIter, class Div_type, class Right_shift, + class Compare> + inline typename boost::enable_if_c< sizeof(size_t) >= sizeof(Div_type), + void >::type + float_sort(RandomAccessIter first, RandomAccessIter last, Div_type, + Right_shift rshift, Compare comp) + { + size_t bin_sizes[1 << max_finishing_splits]; + std::vector<RandomAccessIter> bin_cache; + float_sort_rec<RandomAccessIter, Div_type, Right_shift, Compare, + size_t> + (first, last, bin_cache, 0, bin_sizes, rshift, comp); + } + + //max-sized integer with specialized comparison + template <class RandomAccessIter, class Div_type, class Right_shift, + class Compare> + inline typename boost::enable_if_c< sizeof(size_t) < sizeof(Div_type) + && sizeof(boost::uintmax_t) >= sizeof(Div_type), void >::type + float_sort(RandomAccessIter first, RandomAccessIter last, Div_type, + Right_shift rshift, Compare comp) + { + size_t bin_sizes[1 << max_finishing_splits]; + std::vector<RandomAccessIter> bin_cache; + float_sort_rec<RandomAccessIter, Div_type, Right_shift, Compare, + boost::uintmax_t> + (first, last, bin_cache, 0, bin_sizes, rshift, comp); + } + + //sizeof(Div_type) doesn't match, so use std::sort + template <class RandomAccessIter, class Div_type, class Right_shift, + class Compare> + inline typename boost::disable_if_c< sizeof(boost::uintmax_t) >= + sizeof(Div_type), void >::type + float_sort(RandomAccessIter first, RandomAccessIter last, Div_type, + Right_shift rshift, Compare comp) + { + BOOST_STATIC_WARNING(sizeof(boost::uintmax_t) >= sizeof(Div_type)); + std::sort(first, last, comp); + } + } +} +} +} + +#endif diff --git a/boost/sort/spreadsort/detail/integer_sort.hpp b/boost/sort/spreadsort/detail/integer_sort.hpp index bc14b3585c..6d6886cfd9 100644 --- a/boost/sort/spreadsort/detail/integer_sort.hpp +++ b/boost/sort/spreadsort/detail/integer_sort.hpp @@ -1,494 +1,494 @@ -// Details for templated Spreadsort-based integer_sort.
-
-// Copyright Steven J. Ross 2001 - 2014.
-// Distributed under the Boost Software License, Version 1.0.
-// (See accompanying file LICENSE_1_0.txt or copy at
-// http://www.boost.org/LICENSE_1_0.txt)
-
-// See http://www.boost.org/libs/sort for library home page.
-
-/*
-Some improvements suggested by:
-Phil Endecott and Frank Gennari
-*/
-
-#ifndef BOOST_SORT_SPREADSORT_DETAIL_INTEGER_SORT_HPP
-#define BOOST_SORT_SPREADSORT_DETAIL_INTEGER_SORT_HPP
-#include <algorithm>
-#include <vector>
-#include <limits>
-#include <functional>
-#include <boost/static_assert.hpp>
-#include <boost/serialization/static_warning.hpp>
-#include <boost/utility/enable_if.hpp>
-#include <boost/sort/spreadsort/detail/constants.hpp>
-#include <boost/sort/spreadsort/detail/spreadsort_common.hpp>
-#include <boost/cstdint.hpp>
-
-namespace boost {
-namespace sort {
-namespace spreadsort {
- namespace detail {
- // Return true if the list is sorted. Otherwise, find the minimum and
- // maximum using <.
- template <class RandomAccessIter>
- inline bool
- is_sorted_or_find_extremes(RandomAccessIter current, RandomAccessIter last,
- RandomAccessIter & max, RandomAccessIter & min)
- {
- min = max = current;
- //This assumes we have more than 1 element based on prior checks.
- while (!(*(current + 1) < *current)) {
- //If everything is in sorted order, return
- if (++current == last - 1)
- return true;
- }
-
- //The maximum is the last sorted element
- max = current;
- //Start from the first unsorted element
- while (++current < last) {
- if (*max < *current)
- max = current;
- else if (*current < *min)
- min = current;
- }
- return false;
- }
-
- // Return true if the list is sorted. Otherwise, find the minimum and
- // maximum.
- // Use a user-defined comparison operator
- template <class RandomAccessIter, class Compare>
- inline bool
- is_sorted_or_find_extremes(RandomAccessIter current, RandomAccessIter last,
- RandomAccessIter & max, RandomAccessIter & min, Compare comp)
- {
- min = max = current;
- while (!comp(*(current + 1), *current)) {
- //If everything is in sorted order, return
- if (++current == last - 1)
- return true;
- }
-
- //The maximum is the last sorted element
- max = current;
- while (++current < last) {
- if (comp(*max, *current))
- max = current;
- else if (comp(*current, *min))
- min = current;
- }
- return false;
- }
-
- //Gets a non-negative right bit shift to operate as a logarithmic divisor
- template<unsigned log_mean_bin_size>
- inline int
- get_log_divisor(size_t count, int log_range)
- {
- int log_divisor;
- //If we can finish in one iteration without exceeding either
- //(2 to the max_finishing_splits) or n bins, do so
- if ((log_divisor = log_range - rough_log_2_size(count)) <= 0 &&
- log_range <= max_finishing_splits)
- log_divisor = 0;
- else {
- //otherwise divide the data into an optimized number of pieces
- log_divisor += log_mean_bin_size;
- //Cannot exceed max_splits or cache misses slow down bin lookups
- if ((log_range - log_divisor) > max_splits)
- log_divisor = log_range - max_splits;
- }
- return log_divisor;
- }
-
- //Implementation for recursive integer sorting
- template <class RandomAccessIter, class Div_type, class Size_type>
- inline void
- spreadsort_rec(RandomAccessIter first, RandomAccessIter last,
- std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset
- , size_t *bin_sizes)
- {
- //This step is roughly 10% of runtime, but it helps avoid worst-case
- //behavior and improve behavior with real data
- //If you know the maximum and minimum ahead of time, you can pass those
- //values in and skip this step for the first iteration
- RandomAccessIter max, min;
- if (is_sorted_or_find_extremes(first, last, max, min))
- return;
- RandomAccessIter * target_bin;
- unsigned log_divisor = get_log_divisor<int_log_mean_bin_size>(
- last - first, rough_log_2_size(Size_type((*max >> 0) - (*min >> 0))));
- Div_type div_min = *min >> log_divisor;
- Div_type div_max = *max >> log_divisor;
- unsigned bin_count = unsigned(div_max - div_min) + 1;
- unsigned cache_end;
- RandomAccessIter * bins =
- size_bins(bin_sizes, bin_cache, cache_offset, cache_end, bin_count);
-
- //Calculating the size of each bin; this takes roughly 10% of runtime
- for (RandomAccessIter current = first; current != last;)
- bin_sizes[size_t((*(current++) >> log_divisor) - div_min)]++;
- //Assign the bin positions
- bins[0] = first;
- for (unsigned u = 0; u < bin_count - 1; u++)
- bins[u + 1] = bins[u] + bin_sizes[u];
-
- RandomAccessIter nextbinstart = first;
- //Swap into place
- //This dominates runtime, mostly in the swap and bin lookups
- for (unsigned u = 0; u < bin_count - 1; ++u) {
- RandomAccessIter * local_bin = bins + u;
- nextbinstart += bin_sizes[u];
- //Iterating over each element in this bin
- for (RandomAccessIter current = *local_bin; current < nextbinstart;
- ++current) {
- //Swapping elements in current into place until the correct
- //element has been swapped in
- for (target_bin = (bins + ((*current >> log_divisor) - div_min));
- target_bin != local_bin;
- target_bin = bins + ((*current >> log_divisor) - div_min)) {
- //3-way swap; this is about 1% faster than a 2-way swap
- //The main advantage is less copies are involved per item
- //put in the correct place
- typename std::iterator_traits<RandomAccessIter>::value_type tmp;
- RandomAccessIter b = (*target_bin)++;
- RandomAccessIter * b_bin = bins + ((*b >> log_divisor) - div_min);
- if (b_bin != local_bin) {
- RandomAccessIter c = (*b_bin)++;
- tmp = *c;
- *c = *b;
- }
- else
- tmp = *b;
- *b = *current;
- *current = tmp;
- }
- }
- *local_bin = nextbinstart;
- }
- bins[bin_count - 1] = last;
-
- //If we've bucketsorted, the array is sorted and we should skip recursion
- if (!log_divisor)
- return;
- //log_divisor is the remaining range; calculating the comparison threshold
- size_t max_count =
- get_min_count<int_log_mean_bin_size, int_log_min_split_count,
- int_log_finishing_count>(log_divisor);
-
- //Recursing
- RandomAccessIter lastPos = first;
- for (unsigned u = cache_offset; u < cache_end; lastPos = bin_cache[u],
- ++u) {
- Size_type count = bin_cache[u] - lastPos;
- //don't sort unless there are at least two items to Compare
- if (count < 2)
- continue;
- //using std::sort if its worst-case is better
- if (count < max_count)
- std::sort(lastPos, bin_cache[u]);
- else
- spreadsort_rec<RandomAccessIter, Div_type, Size_type>(lastPos,
- bin_cache[u],
- bin_cache,
- cache_end,
- bin_sizes);
- }
- }
-
- //Generic bitshift-based 3-way swapping code
- template <class RandomAccessIter, class Div_type, class Right_shift>
- inline void inner_swap_loop(RandomAccessIter * bins,
- const RandomAccessIter & next_bin_start, unsigned ii, Right_shift &rshift
- , const unsigned log_divisor, const Div_type div_min)
- {
- RandomAccessIter * local_bin = bins + ii;
- for (RandomAccessIter current = *local_bin; current < next_bin_start;
- ++current) {
- for (RandomAccessIter * target_bin =
- (bins + (rshift(*current, log_divisor) - div_min));
- target_bin != local_bin;
- target_bin = bins + (rshift(*current, log_divisor) - div_min)) {
- typename std::iterator_traits<RandomAccessIter>::value_type tmp;
- RandomAccessIter b = (*target_bin)++;
- RandomAccessIter * b_bin =
- bins + (rshift(*b, log_divisor) - div_min);
- //Three-way swap; if the item to be swapped doesn't belong
- //in the current bin, swap it to where it belongs
- if (b_bin != local_bin) {
- RandomAccessIter c = (*b_bin)++;
- tmp = *c;
- *c = *b;
- }
- //Note: we could increment current once the swap is done in this case
- //but that seems to impair performance
- else
- tmp = *b;
- *b = *current;
- *current = tmp;
- }
- }
- *local_bin = next_bin_start;
- }
-
- //Standard swapping wrapper for ascending values
- template <class RandomAccessIter, class Div_type, class Right_shift>
- inline void swap_loop(RandomAccessIter * bins,
- RandomAccessIter & next_bin_start, unsigned ii, Right_shift &rshift
- , const size_t *bin_sizes
- , const unsigned log_divisor, const Div_type div_min)
- {
- next_bin_start += bin_sizes[ii];
- inner_swap_loop<RandomAccessIter, Div_type, Right_shift>(bins,
- next_bin_start, ii, rshift, log_divisor, div_min);
- }
-
- //Functor implementation for recursive sorting
- template <class RandomAccessIter, class Div_type, class Right_shift,
- class Compare, class Size_type, unsigned log_mean_bin_size,
- unsigned log_min_split_count, unsigned log_finishing_count>
- inline void
- spreadsort_rec(RandomAccessIter first, RandomAccessIter last,
- std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset
- , size_t *bin_sizes, Right_shift rshift, Compare comp)
- {
- RandomAccessIter max, min;
- if (is_sorted_or_find_extremes(first, last, max, min, comp))
- return;
- unsigned log_divisor = get_log_divisor<log_mean_bin_size>(last - first,
- rough_log_2_size(Size_type(rshift(*max, 0) - rshift(*min, 0))));
- Div_type div_min = rshift(*min, log_divisor);
- Div_type div_max = rshift(*max, log_divisor);
- unsigned bin_count = unsigned(div_max - div_min) + 1;
- unsigned cache_end;
- RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset,
- cache_end, bin_count);
-
- //Calculating the size of each bin
- for (RandomAccessIter current = first; current != last;)
- bin_sizes[unsigned(rshift(*(current++), log_divisor) - div_min)]++;
- bins[0] = first;
- for (unsigned u = 0; u < bin_count - 1; u++)
- bins[u + 1] = bins[u] + bin_sizes[u];
-
- //Swap into place
- RandomAccessIter next_bin_start = first;
- for (unsigned u = 0; u < bin_count - 1; ++u)
- swap_loop<RandomAccessIter, Div_type, Right_shift>(bins, next_bin_start,
- u, rshift, bin_sizes, log_divisor, div_min);
- bins[bin_count - 1] = last;
-
- //If we've bucketsorted, the array is sorted
- if (!log_divisor)
- return;
-
- //Recursing
- size_t max_count = get_min_count<log_mean_bin_size, log_min_split_count,
- log_finishing_count>(log_divisor);
- RandomAccessIter lastPos = first;
- for (unsigned u = cache_offset; u < cache_end; lastPos = bin_cache[u],
- ++u) {
- size_t count = bin_cache[u] - lastPos;
- if (count < 2)
- continue;
- if (count < max_count)
- std::sort(lastPos, bin_cache[u], comp);
- else
- spreadsort_rec<RandomAccessIter, Div_type, Right_shift, Compare,
- Size_type, log_mean_bin_size, log_min_split_count, log_finishing_count>
- (lastPos, bin_cache[u], bin_cache, cache_end, bin_sizes, rshift, comp);
- }
- }
-
- //Functor implementation for recursive sorting with only Shift overridden
- template <class RandomAccessIter, class Div_type, class Right_shift,
- class Size_type, unsigned log_mean_bin_size,
- unsigned log_min_split_count, unsigned log_finishing_count>
- inline void
- spreadsort_rec(RandomAccessIter first, RandomAccessIter last,
- std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset
- , size_t *bin_sizes, Right_shift rshift)
- {
- RandomAccessIter max, min;
- if (is_sorted_or_find_extremes(first, last, max, min))
- return;
- unsigned log_divisor = get_log_divisor<log_mean_bin_size>(last - first,
- rough_log_2_size(Size_type(rshift(*max, 0) - rshift(*min, 0))));
- Div_type div_min = rshift(*min, log_divisor);
- Div_type div_max = rshift(*max, log_divisor);
- unsigned bin_count = unsigned(div_max - div_min) + 1;
- unsigned cache_end;
- RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset,
- cache_end, bin_count);
-
- //Calculating the size of each bin
- for (RandomAccessIter current = first; current != last;)
- bin_sizes[unsigned(rshift(*(current++), log_divisor) - div_min)]++;
- bins[0] = first;
- for (unsigned u = 0; u < bin_count - 1; u++)
- bins[u + 1] = bins[u] + bin_sizes[u];
-
- //Swap into place
- RandomAccessIter nextbinstart = first;
- for (unsigned ii = 0; ii < bin_count - 1; ++ii)
- swap_loop<RandomAccessIter, Div_type, Right_shift>(bins, nextbinstart,
- ii, rshift, bin_sizes, log_divisor, div_min);
- bins[bin_count - 1] = last;
-
- //If we've bucketsorted, the array is sorted
- if (!log_divisor)
- return;
-
- //Recursing
- size_t max_count = get_min_count<log_mean_bin_size, log_min_split_count,
- log_finishing_count>(log_divisor);
- RandomAccessIter lastPos = first;
- for (unsigned u = cache_offset; u < cache_end; lastPos = bin_cache[u],
- ++u) {
- size_t count = bin_cache[u] - lastPos;
- if (count < 2)
- continue;
- if (count < max_count)
- std::sort(lastPos, bin_cache[u]);
- else
- spreadsort_rec<RandomAccessIter, Div_type, Right_shift, Size_type,
- log_mean_bin_size, log_min_split_count, log_finishing_count>(lastPos,
- bin_cache[u], bin_cache, cache_end, bin_sizes, rshift);
- }
- }
-
- //Holds the bin vector and makes the initial recursive call
- template <class RandomAccessIter, class Div_type>
- //Only use spreadsort if the integer can fit in a size_t
- inline typename boost::enable_if_c< sizeof(Div_type) <= sizeof(size_t),
- void >::type
- integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type)
- {
- size_t bin_sizes[1 << max_finishing_splits];
- std::vector<RandomAccessIter> bin_cache;
- spreadsort_rec<RandomAccessIter, Div_type, size_t>(first, last,
- bin_cache, 0, bin_sizes);
- }
-
- //Holds the bin vector and makes the initial recursive call
- template <class RandomAccessIter, class Div_type>
- //Only use spreadsort if the integer can fit in a uintmax_t
- inline typename boost::enable_if_c< (sizeof(Div_type) > sizeof(size_t))
- && sizeof(Div_type) <= sizeof(boost::uintmax_t), void >::type
- integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type)
- {
- size_t bin_sizes[1 << max_finishing_splits];
- std::vector<RandomAccessIter> bin_cache;
- spreadsort_rec<RandomAccessIter, Div_type, boost::uintmax_t>(first,
- last, bin_cache, 0, bin_sizes);
- }
-
- template <class RandomAccessIter, class Div_type>
- inline typename boost::disable_if_c< sizeof(Div_type) <= sizeof(size_t)
- || sizeof(Div_type) <= sizeof(boost::uintmax_t), void >::type
- //defaulting to std::sort when integer_sort won't work
- integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type)
- {
- //Warning that we're using std::sort, even though integer_sort was called
- BOOST_STATIC_WARNING( sizeof(Div_type) <= sizeof(size_t) );
- std::sort(first, last);
- }
-
-
- //Same for the full functor version
- template <class RandomAccessIter, class Div_type, class Right_shift,
- class Compare>
- //Only use spreadsort if the integer can fit in a size_t
- inline typename boost::enable_if_c< sizeof(Div_type) <= sizeof(size_t),
- void >::type
- integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type,
- Right_shift shift, Compare comp)
- {
- size_t bin_sizes[1 << max_finishing_splits];
- std::vector<RandomAccessIter> bin_cache;
- spreadsort_rec<RandomAccessIter, Div_type, Right_shift, Compare,
- size_t, int_log_mean_bin_size, int_log_min_split_count,
- int_log_finishing_count>
- (first, last, bin_cache, 0, bin_sizes, shift, comp);
- }
-
- template <class RandomAccessIter, class Div_type, class Right_shift,
- class Compare>
- //Only use spreadsort if the integer can fit in a uintmax_t
- inline typename boost::enable_if_c< (sizeof(Div_type) > sizeof(size_t))
- && sizeof(Div_type) <= sizeof(boost::uintmax_t), void >::type
- integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type,
- Right_shift shift, Compare comp)
- {
- size_t bin_sizes[1 << max_finishing_splits];
- std::vector<RandomAccessIter> bin_cache;
- spreadsort_rec<RandomAccessIter, Div_type, Right_shift, Compare,
- boost::uintmax_t, int_log_mean_bin_size,
- int_log_min_split_count, int_log_finishing_count>
- (first, last, bin_cache, 0, bin_sizes, shift, comp);
- }
-
- template <class RandomAccessIter, class Div_type, class Right_shift,
- class Compare>
- inline typename boost::disable_if_c< sizeof(Div_type) <= sizeof(size_t)
- || sizeof(Div_type) <= sizeof(boost::uintmax_t), void >::type
- //defaulting to std::sort when integer_sort won't work
- integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type,
- Right_shift shift, Compare comp)
- {
- //Warning that we're using std::sort, even though integer_sort was called
- BOOST_STATIC_WARNING( sizeof(Div_type) <= sizeof(size_t) );
- std::sort(first, last, comp);
- }
-
-
- //Same for the right shift version
- template <class RandomAccessIter, class Div_type, class Right_shift>
- //Only use spreadsort if the integer can fit in a size_t
- inline typename boost::enable_if_c< sizeof(Div_type) <= sizeof(size_t),
- void >::type
- integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type,
- Right_shift shift)
- {
- size_t bin_sizes[1 << max_finishing_splits];
- std::vector<RandomAccessIter> bin_cache;
- spreadsort_rec<RandomAccessIter, Div_type, Right_shift, size_t,
- int_log_mean_bin_size, int_log_min_split_count,
- int_log_finishing_count>
- (first, last, bin_cache, 0, bin_sizes, shift);
- }
-
- template <class RandomAccessIter, class Div_type, class Right_shift>
- //Only use spreadsort if the integer can fit in a uintmax_t
- inline typename boost::enable_if_c< (sizeof(Div_type) > sizeof(size_t))
- && sizeof(Div_type) <= sizeof(boost::uintmax_t), void >::type
- integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type,
- Right_shift shift)
- {
- size_t bin_sizes[1 << max_finishing_splits];
- std::vector<RandomAccessIter> bin_cache;
- spreadsort_rec<RandomAccessIter, Div_type, Right_shift,
- boost::uintmax_t, int_log_mean_bin_size,
- int_log_min_split_count, int_log_finishing_count>
- (first, last, bin_cache, 0, bin_sizes, shift);
- }
-
- template <class RandomAccessIter, class Div_type, class Right_shift>
- inline typename boost::disable_if_c< sizeof(Div_type) <= sizeof(size_t)
- || sizeof(Div_type) <= sizeof(boost::uintmax_t), void >::type
- //defaulting to std::sort when integer_sort won't work
- integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type,
- Right_shift shift)
- {
- //Warning that we're using std::sort, even though integer_sort was called
- BOOST_STATIC_WARNING( sizeof(Div_type) <= sizeof(size_t) );
- std::sort(first, last);
- }
- }
-}
-}
-}
-
-#endif
+// Details for templated Spreadsort-based integer_sort. + +// Copyright Steven J. Ross 2001 - 2014. +// Distributed under the Boost Software License, Version 1.0. +// (See accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) + +// See http://www.boost.org/libs/sort for library home page. + +/* +Some improvements suggested by: +Phil Endecott and Frank Gennari +*/ + +#ifndef BOOST_SORT_SPREADSORT_DETAIL_INTEGER_SORT_HPP +#define BOOST_SORT_SPREADSORT_DETAIL_INTEGER_SORT_HPP +#include <algorithm> +#include <vector> +#include <limits> +#include <functional> +#include <boost/static_assert.hpp> +#include <boost/serialization/static_warning.hpp> +#include <boost/utility/enable_if.hpp> +#include <boost/sort/spreadsort/detail/constants.hpp> +#include <boost/sort/spreadsort/detail/spreadsort_common.hpp> +#include <boost/cstdint.hpp> + +namespace boost { +namespace sort { +namespace spreadsort { + namespace detail { + // Return true if the list is sorted. Otherwise, find the minimum and + // maximum using <. + template <class RandomAccessIter> + inline bool + is_sorted_or_find_extremes(RandomAccessIter current, RandomAccessIter last, + RandomAccessIter & max, RandomAccessIter & min) + { + min = max = current; + //This assumes we have more than 1 element based on prior checks. + while (!(*(current + 1) < *current)) { + //If everything is in sorted order, return + if (++current == last - 1) + return true; + } + + //The maximum is the last sorted element + max = current; + //Start from the first unsorted element + while (++current < last) { + if (*max < *current) + max = current; + else if (*current < *min) + min = current; + } + return false; + } + + // Return true if the list is sorted. Otherwise, find the minimum and + // maximum. + // Use a user-defined comparison operator + template <class RandomAccessIter, class Compare> + inline bool + is_sorted_or_find_extremes(RandomAccessIter current, RandomAccessIter last, + RandomAccessIter & max, RandomAccessIter & min, Compare comp) + { + min = max = current; + while (!comp(*(current + 1), *current)) { + //If everything is in sorted order, return + if (++current == last - 1) + return true; + } + + //The maximum is the last sorted element + max = current; + while (++current < last) { + if (comp(*max, *current)) + max = current; + else if (comp(*current, *min)) + min = current; + } + return false; + } + + //Gets a non-negative right bit shift to operate as a logarithmic divisor + template<unsigned log_mean_bin_size> + inline int + get_log_divisor(size_t count, int log_range) + { + int log_divisor; + //If we can finish in one iteration without exceeding either + //(2 to the max_finishing_splits) or n bins, do so + if ((log_divisor = log_range - rough_log_2_size(count)) <= 0 && + log_range <= max_finishing_splits) + log_divisor = 0; + else { + //otherwise divide the data into an optimized number of pieces + log_divisor += log_mean_bin_size; + //Cannot exceed max_splits or cache misses slow down bin lookups + if ((log_range - log_divisor) > max_splits) + log_divisor = log_range - max_splits; + } + return log_divisor; + } + + //Implementation for recursive integer sorting + template <class RandomAccessIter, class Div_type, class Size_type> + inline void + spreadsort_rec(RandomAccessIter first, RandomAccessIter last, + std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset + , size_t *bin_sizes) + { + //This step is roughly 10% of runtime, but it helps avoid worst-case + //behavior and improve behavior with real data + //If you know the maximum and minimum ahead of time, you can pass those + //values in and skip this step for the first iteration + RandomAccessIter max, min; + if (is_sorted_or_find_extremes(first, last, max, min)) + return; + RandomAccessIter * target_bin; + unsigned log_divisor = get_log_divisor<int_log_mean_bin_size>( + last - first, rough_log_2_size(Size_type((*max >> 0) - (*min >> 0)))); + Div_type div_min = *min >> log_divisor; + Div_type div_max = *max >> log_divisor; + unsigned bin_count = unsigned(div_max - div_min) + 1; + unsigned cache_end; + RandomAccessIter * bins = + size_bins(bin_sizes, bin_cache, cache_offset, cache_end, bin_count); + + //Calculating the size of each bin; this takes roughly 10% of runtime + for (RandomAccessIter current = first; current != last;) + bin_sizes[size_t((*(current++) >> log_divisor) - div_min)]++; + //Assign the bin positions + bins[0] = first; + for (unsigned u = 0; u < bin_count - 1; u++) + bins[u + 1] = bins[u] + bin_sizes[u]; + + RandomAccessIter nextbinstart = first; + //Swap into place + //This dominates runtime, mostly in the swap and bin lookups + for (unsigned u = 0; u < bin_count - 1; ++u) { + RandomAccessIter * local_bin = bins + u; + nextbinstart += bin_sizes[u]; + //Iterating over each element in this bin + for (RandomAccessIter current = *local_bin; current < nextbinstart; + ++current) { + //Swapping elements in current into place until the correct + //element has been swapped in + for (target_bin = (bins + ((*current >> log_divisor) - div_min)); + target_bin != local_bin; + target_bin = bins + ((*current >> log_divisor) - div_min)) { + //3-way swap; this is about 1% faster than a 2-way swap + //The main advantage is less copies are involved per item + //put in the correct place + typename std::iterator_traits<RandomAccessIter>::value_type tmp; + RandomAccessIter b = (*target_bin)++; + RandomAccessIter * b_bin = bins + ((*b >> log_divisor) - div_min); + if (b_bin != local_bin) { + RandomAccessIter c = (*b_bin)++; + tmp = *c; + *c = *b; + } + else + tmp = *b; + *b = *current; + *current = tmp; + } + } + *local_bin = nextbinstart; + } + bins[bin_count - 1] = last; + + //If we've bucketsorted, the array is sorted and we should skip recursion + if (!log_divisor) + return; + //log_divisor is the remaining range; calculating the comparison threshold + size_t max_count = + get_min_count<int_log_mean_bin_size, int_log_min_split_count, + int_log_finishing_count>(log_divisor); + + //Recursing + RandomAccessIter lastPos = first; + for (unsigned u = cache_offset; u < cache_end; lastPos = bin_cache[u], + ++u) { + Size_type count = bin_cache[u] - lastPos; + //don't sort unless there are at least two items to Compare + if (count < 2) + continue; + //using std::sort if its worst-case is better + if (count < max_count) + std::sort(lastPos, bin_cache[u]); + else + spreadsort_rec<RandomAccessIter, Div_type, Size_type>(lastPos, + bin_cache[u], + bin_cache, + cache_end, + bin_sizes); + } + } + + //Generic bitshift-based 3-way swapping code + template <class RandomAccessIter, class Div_type, class Right_shift> + inline void inner_swap_loop(RandomAccessIter * bins, + const RandomAccessIter & next_bin_start, unsigned ii, Right_shift &rshift + , const unsigned log_divisor, const Div_type div_min) + { + RandomAccessIter * local_bin = bins + ii; + for (RandomAccessIter current = *local_bin; current < next_bin_start; + ++current) { + for (RandomAccessIter * target_bin = + (bins + (rshift(*current, log_divisor) - div_min)); + target_bin != local_bin; + target_bin = bins + (rshift(*current, log_divisor) - div_min)) { + typename std::iterator_traits<RandomAccessIter>::value_type tmp; + RandomAccessIter b = (*target_bin)++; + RandomAccessIter * b_bin = + bins + (rshift(*b, log_divisor) - div_min); + //Three-way swap; if the item to be swapped doesn't belong + //in the current bin, swap it to where it belongs + if (b_bin != local_bin) { + RandomAccessIter c = (*b_bin)++; + tmp = *c; + *c = *b; + } + //Note: we could increment current once the swap is done in this case + //but that seems to impair performance + else + tmp = *b; + *b = *current; + *current = tmp; + } + } + *local_bin = next_bin_start; + } + + //Standard swapping wrapper for ascending values + template <class RandomAccessIter, class Div_type, class Right_shift> + inline void swap_loop(RandomAccessIter * bins, + RandomAccessIter & next_bin_start, unsigned ii, Right_shift &rshift + , const size_t *bin_sizes + , const unsigned log_divisor, const Div_type div_min) + { + next_bin_start += bin_sizes[ii]; + inner_swap_loop<RandomAccessIter, Div_type, Right_shift>(bins, + next_bin_start, ii, rshift, log_divisor, div_min); + } + + //Functor implementation for recursive sorting + template <class RandomAccessIter, class Div_type, class Right_shift, + class Compare, class Size_type, unsigned log_mean_bin_size, + unsigned log_min_split_count, unsigned log_finishing_count> + inline void + spreadsort_rec(RandomAccessIter first, RandomAccessIter last, + std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset + , size_t *bin_sizes, Right_shift rshift, Compare comp) + { + RandomAccessIter max, min; + if (is_sorted_or_find_extremes(first, last, max, min, comp)) + return; + unsigned log_divisor = get_log_divisor<log_mean_bin_size>(last - first, + rough_log_2_size(Size_type(rshift(*max, 0) - rshift(*min, 0)))); + Div_type div_min = rshift(*min, log_divisor); + Div_type div_max = rshift(*max, log_divisor); + unsigned bin_count = unsigned(div_max - div_min) + 1; + unsigned cache_end; + RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset, + cache_end, bin_count); + + //Calculating the size of each bin + for (RandomAccessIter current = first; current != last;) + bin_sizes[unsigned(rshift(*(current++), log_divisor) - div_min)]++; + bins[0] = first; + for (unsigned u = 0; u < bin_count - 1; u++) + bins[u + 1] = bins[u] + bin_sizes[u]; + + //Swap into place + RandomAccessIter next_bin_start = first; + for (unsigned u = 0; u < bin_count - 1; ++u) + swap_loop<RandomAccessIter, Div_type, Right_shift>(bins, next_bin_start, + u, rshift, bin_sizes, log_divisor, div_min); + bins[bin_count - 1] = last; + + //If we've bucketsorted, the array is sorted + if (!log_divisor) + return; + + //Recursing + size_t max_count = get_min_count<log_mean_bin_size, log_min_split_count, + log_finishing_count>(log_divisor); + RandomAccessIter lastPos = first; + for (unsigned u = cache_offset; u < cache_end; lastPos = bin_cache[u], + ++u) { + size_t count = bin_cache[u] - lastPos; + if (count < 2) + continue; + if (count < max_count) + std::sort(lastPos, bin_cache[u], comp); + else + spreadsort_rec<RandomAccessIter, Div_type, Right_shift, Compare, + Size_type, log_mean_bin_size, log_min_split_count, log_finishing_count> + (lastPos, bin_cache[u], bin_cache, cache_end, bin_sizes, rshift, comp); + } + } + + //Functor implementation for recursive sorting with only Shift overridden + template <class RandomAccessIter, class Div_type, class Right_shift, + class Size_type, unsigned log_mean_bin_size, + unsigned log_min_split_count, unsigned log_finishing_count> + inline void + spreadsort_rec(RandomAccessIter first, RandomAccessIter last, + std::vector<RandomAccessIter> &bin_cache, unsigned cache_offset + , size_t *bin_sizes, Right_shift rshift) + { + RandomAccessIter max, min; + if (is_sorted_or_find_extremes(first, last, max, min)) + return; + unsigned log_divisor = get_log_divisor<log_mean_bin_size>(last - first, + rough_log_2_size(Size_type(rshift(*max, 0) - rshift(*min, 0)))); + Div_type div_min = rshift(*min, log_divisor); + Div_type div_max = rshift(*max, log_divisor); + unsigned bin_count = unsigned(div_max - div_min) + 1; + unsigned cache_end; + RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset, + cache_end, bin_count); + + //Calculating the size of each bin + for (RandomAccessIter current = first; current != last;) + bin_sizes[unsigned(rshift(*(current++), log_divisor) - div_min)]++; + bins[0] = first; + for (unsigned u = 0; u < bin_count - 1; u++) + bins[u + 1] = bins[u] + bin_sizes[u]; + + //Swap into place + RandomAccessIter nextbinstart = first; + for (unsigned ii = 0; ii < bin_count - 1; ++ii) + swap_loop<RandomAccessIter, Div_type, Right_shift>(bins, nextbinstart, + ii, rshift, bin_sizes, log_divisor, div_min); + bins[bin_count - 1] = last; + + //If we've bucketsorted, the array is sorted + if (!log_divisor) + return; + + //Recursing + size_t max_count = get_min_count<log_mean_bin_size, log_min_split_count, + log_finishing_count>(log_divisor); + RandomAccessIter lastPos = first; + for (unsigned u = cache_offset; u < cache_end; lastPos = bin_cache[u], + ++u) { + size_t count = bin_cache[u] - lastPos; + if (count < 2) + continue; + if (count < max_count) + std::sort(lastPos, bin_cache[u]); + else + spreadsort_rec<RandomAccessIter, Div_type, Right_shift, Size_type, + log_mean_bin_size, log_min_split_count, log_finishing_count>(lastPos, + bin_cache[u], bin_cache, cache_end, bin_sizes, rshift); + } + } + + //Holds the bin vector and makes the initial recursive call + template <class RandomAccessIter, class Div_type> + //Only use spreadsort if the integer can fit in a size_t + inline typename boost::enable_if_c< sizeof(Div_type) <= sizeof(size_t), + void >::type + integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type) + { + size_t bin_sizes[1 << max_finishing_splits]; + std::vector<RandomAccessIter> bin_cache; + spreadsort_rec<RandomAccessIter, Div_type, size_t>(first, last, + bin_cache, 0, bin_sizes); + } + + //Holds the bin vector and makes the initial recursive call + template <class RandomAccessIter, class Div_type> + //Only use spreadsort if the integer can fit in a uintmax_t + inline typename boost::enable_if_c< (sizeof(Div_type) > sizeof(size_t)) + && sizeof(Div_type) <= sizeof(boost::uintmax_t), void >::type + integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type) + { + size_t bin_sizes[1 << max_finishing_splits]; + std::vector<RandomAccessIter> bin_cache; + spreadsort_rec<RandomAccessIter, Div_type, boost::uintmax_t>(first, + last, bin_cache, 0, bin_sizes); + } + + template <class RandomAccessIter, class Div_type> + inline typename boost::disable_if_c< sizeof(Div_type) <= sizeof(size_t) + || sizeof(Div_type) <= sizeof(boost::uintmax_t), void >::type + //defaulting to std::sort when integer_sort won't work + integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type) + { + //Warning that we're using std::sort, even though integer_sort was called + BOOST_STATIC_WARNING( sizeof(Div_type) <= sizeof(size_t) ); + std::sort(first, last); + } + + + //Same for the full functor version + template <class RandomAccessIter, class Div_type, class Right_shift, + class Compare> + //Only use spreadsort if the integer can fit in a size_t + inline typename boost::enable_if_c< sizeof(Div_type) <= sizeof(size_t), + void >::type + integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type, + Right_shift shift, Compare comp) + { + size_t bin_sizes[1 << max_finishing_splits]; + std::vector<RandomAccessIter> bin_cache; + spreadsort_rec<RandomAccessIter, Div_type, Right_shift, Compare, + size_t, int_log_mean_bin_size, int_log_min_split_count, + int_log_finishing_count> + (first, last, bin_cache, 0, bin_sizes, shift, comp); + } + + template <class RandomAccessIter, class Div_type, class Right_shift, + class Compare> + //Only use spreadsort if the integer can fit in a uintmax_t + inline typename boost::enable_if_c< (sizeof(Div_type) > sizeof(size_t)) + && sizeof(Div_type) <= sizeof(boost::uintmax_t), void >::type + integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type, + Right_shift shift, Compare comp) + { + size_t bin_sizes[1 << max_finishing_splits]; + std::vector<RandomAccessIter> bin_cache; + spreadsort_rec<RandomAccessIter, Div_type, Right_shift, Compare, + boost::uintmax_t, int_log_mean_bin_size, + int_log_min_split_count, int_log_finishing_count> + (first, last, bin_cache, 0, bin_sizes, shift, comp); + } + + template <class RandomAccessIter, class Div_type, class Right_shift, + class Compare> + inline typename boost::disable_if_c< sizeof(Div_type) <= sizeof(size_t) + || sizeof(Div_type) <= sizeof(boost::uintmax_t), void >::type + //defaulting to std::sort when integer_sort won't work + integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type, + Right_shift shift, Compare comp) + { + //Warning that we're using std::sort, even though integer_sort was called + BOOST_STATIC_WARNING( sizeof(Div_type) <= sizeof(size_t) ); + std::sort(first, last, comp); + } + + + //Same for the right shift version + template <class RandomAccessIter, class Div_type, class Right_shift> + //Only use spreadsort if the integer can fit in a size_t + inline typename boost::enable_if_c< sizeof(Div_type) <= sizeof(size_t), + void >::type + integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type, + Right_shift shift) + { + size_t bin_sizes[1 << max_finishing_splits]; + std::vector<RandomAccessIter> bin_cache; + spreadsort_rec<RandomAccessIter, Div_type, Right_shift, size_t, + int_log_mean_bin_size, int_log_min_split_count, + int_log_finishing_count> + (first, last, bin_cache, 0, bin_sizes, shift); + } + + template <class RandomAccessIter, class Div_type, class Right_shift> + //Only use spreadsort if the integer can fit in a uintmax_t + inline typename boost::enable_if_c< (sizeof(Div_type) > sizeof(size_t)) + && sizeof(Div_type) <= sizeof(boost::uintmax_t), void >::type + integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type, + Right_shift shift) + { + size_t bin_sizes[1 << max_finishing_splits]; + std::vector<RandomAccessIter> bin_cache; + spreadsort_rec<RandomAccessIter, Div_type, Right_shift, + boost::uintmax_t, int_log_mean_bin_size, + int_log_min_split_count, int_log_finishing_count> + (first, last, bin_cache, 0, bin_sizes, shift); + } + + template <class RandomAccessIter, class Div_type, class Right_shift> + inline typename boost::disable_if_c< sizeof(Div_type) <= sizeof(size_t) + || sizeof(Div_type) <= sizeof(boost::uintmax_t), void >::type + //defaulting to std::sort when integer_sort won't work + integer_sort(RandomAccessIter first, RandomAccessIter last, Div_type, + Right_shift shift) + { + //Warning that we're using std::sort, even though integer_sort was called + BOOST_STATIC_WARNING( sizeof(Div_type) <= sizeof(size_t) ); + std::sort(first, last); + } + } +} +} +} + +#endif diff --git a/boost/sort/spreadsort/detail/spreadsort_common.hpp b/boost/sort/spreadsort/detail/spreadsort_common.hpp index 7b299ad5f3..7917fddae0 100644 --- a/boost/sort/spreadsort/detail/spreadsort_common.hpp +++ b/boost/sort/spreadsort/detail/spreadsort_common.hpp @@ -1,124 +1,124 @@ -// Contains get_min_count, the core optimization of the spreadsort algorithm.
-// Also has other helper functions commonly useful across variants.
-
-// Copyright Steven J. Ross 2001 - 2014.
-// Distributed under the Boost Software License, Version 1.0.
-// (See accompanying file LICENSE_1_0.txt or copy at
-// http://www.boost.org/LICENSE_1_0.txt)
-
-// See http://www.boost.org/libs/sort for library home page.
-
-/*
-Some improvements suggested by:
-Phil Endecott and Frank Gennari
-*/
-
-#ifndef BOOST_SORT_SPREADSORT_DETAIL_SPREAD_SORT_COMMON_HPP
-#define BOOST_SORT_SPREADSORT_DETAIL_SPREAD_SORT_COMMON_HPP
-#include <algorithm>
-#include <vector>
-#include <cstring>
-#include <limits>
-#include <functional>
-#include <boost/static_assert.hpp>
-#include <boost/serialization/static_warning.hpp>
-#include <boost/sort/spreadsort/detail/constants.hpp>
-#include <boost/cstdint.hpp>
-
-namespace boost {
-namespace sort {
-namespace spreadsort {
- namespace detail {
- //This only works on unsigned data types
- template <typename T>
- inline unsigned
- rough_log_2_size(const T& input)
- {
- unsigned result = 0;
- //The && is necessary on some compilers to avoid infinite loops
- //it doesn't significantly impair performance
- while ((input >> result) && (result < (8*sizeof(T)))) ++result;
- return result;
- }
-
- //Gets the minimum size to call spreadsort on to control worst-case runtime.
- //This is called for a set of bins, instead of bin-by-bin, to minimize
- //runtime overhead.
- //This could be replaced by a lookup table of sizeof(Div_type)*8 but this
- //function is more general.
- template<unsigned log_mean_bin_size,
- unsigned log_min_split_count, unsigned log_finishing_count>
- inline size_t
- get_min_count(unsigned log_range)
- {
- const size_t typed_one = 1;
- const unsigned min_size = log_mean_bin_size + log_min_split_count;
- //Assuring that constants have valid settings
- BOOST_STATIC_ASSERT(log_min_split_count <= max_splits &&
- log_min_split_count > 0);
- BOOST_STATIC_ASSERT(max_splits > 1 &&
- max_splits < (8 * sizeof(unsigned)));
- BOOST_STATIC_ASSERT(max_finishing_splits >= max_splits &&
- max_finishing_splits < (8 * sizeof(unsigned)));
- BOOST_STATIC_ASSERT(log_mean_bin_size >= 0);
- BOOST_STATIC_ASSERT(log_finishing_count >= 0);
- //if we can complete in one iteration, do so
- //This first check allows the compiler to optimize never-executed code out
- if (log_finishing_count < min_size) {
- if (log_range <= min_size && log_range <= max_splits) {
- //Return no smaller than a certain minimum limit
- if (log_range <= log_finishing_count)
- return typed_one << log_finishing_count;
- return typed_one << log_range;
- }
- }
- const unsigned base_iterations = max_splits - log_min_split_count;
- //sum of n to n + x = ((x + 1) * (n + (n + x)))/2 + log_mean_bin_size
- const unsigned base_range =
- ((base_iterations + 1) * (max_splits + log_min_split_count))/2
- + log_mean_bin_size;
- //Calculating the required number of iterations, and returning
- //1 << (iteration_count + min_size)
- if (log_range < base_range) {
- unsigned result = log_min_split_count;
- for (unsigned offset = min_size; offset < log_range;
- offset += ++result);
- //Preventing overflow; this situation shouldn't occur
- if ((result + log_mean_bin_size) >= (8 * sizeof(size_t)))
- return typed_one << ((8 * sizeof(size_t)) - 1);
- return typed_one << (result + log_mean_bin_size);
- }
- //A quick division can calculate the worst-case runtime for larger ranges
- unsigned remainder = log_range - base_range;
- //the max_splits - 1 is used to calculate the ceiling of the division
- unsigned bit_length = ((((max_splits - 1) + remainder)/max_splits)
- + base_iterations + min_size);
- //Preventing overflow; this situation shouldn't occur
- if (bit_length >= (8 * sizeof(size_t)))
- return typed_one << ((8 * sizeof(size_t)) - 1);
- //n(log_range)/max_splits + C, optimizing worst-case performance
- return typed_one << bit_length;
- }
-
- // Resizes the bin cache and bin sizes, and initializes each bin size to 0.
- // This generates the memory overhead to use in radix sorting.
- template <class RandomAccessIter>
- inline RandomAccessIter *
- size_bins(size_t *bin_sizes, std::vector<RandomAccessIter>
- &bin_cache, unsigned cache_offset, unsigned &cache_end, unsigned bin_count)
- {
- // Clear the bin sizes
- for (size_t u = 0; u < bin_count; u++)
- bin_sizes[u] = 0;
- //Make sure there is space for the bins
- cache_end = cache_offset + bin_count;
- if (cache_end > bin_cache.size())
- bin_cache.resize(cache_end);
- return &(bin_cache[cache_offset]);
- }
- }
-}
-}
-}
-
-#endif
+// Contains get_min_count, the core optimization of the spreadsort algorithm. +// Also has other helper functions commonly useful across variants. + +// Copyright Steven J. Ross 2001 - 2014. +// Distributed under the Boost Software License, Version 1.0. +// (See accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) + +// See http://www.boost.org/libs/sort for library home page. + +/* +Some improvements suggested by: +Phil Endecott and Frank Gennari +*/ + +#ifndef BOOST_SORT_SPREADSORT_DETAIL_SPREAD_SORT_COMMON_HPP +#define BOOST_SORT_SPREADSORT_DETAIL_SPREAD_SORT_COMMON_HPP +#include <algorithm> +#include <vector> +#include <cstring> +#include <limits> +#include <functional> +#include <boost/static_assert.hpp> +#include <boost/serialization/static_warning.hpp> +#include <boost/sort/spreadsort/detail/constants.hpp> +#include <boost/cstdint.hpp> + +namespace boost { +namespace sort { +namespace spreadsort { + namespace detail { + //This only works on unsigned data types + template <typename T> + inline unsigned + rough_log_2_size(const T& input) + { + unsigned result = 0; + //The && is necessary on some compilers to avoid infinite loops + //it doesn't significantly impair performance + while ((input >> result) && (result < (8*sizeof(T)))) ++result; + return result; + } + + //Gets the minimum size to call spreadsort on to control worst-case runtime. + //This is called for a set of bins, instead of bin-by-bin, to minimize + //runtime overhead. + //This could be replaced by a lookup table of sizeof(Div_type)*8 but this + //function is more general. + template<unsigned log_mean_bin_size, + unsigned log_min_split_count, unsigned log_finishing_count> + inline size_t + get_min_count(unsigned log_range) + { + const size_t typed_one = 1; + const unsigned min_size = log_mean_bin_size + log_min_split_count; + //Assuring that constants have valid settings + BOOST_STATIC_ASSERT(log_min_split_count <= max_splits && + log_min_split_count > 0); + BOOST_STATIC_ASSERT(max_splits > 1 && + max_splits < (8 * sizeof(unsigned))); + BOOST_STATIC_ASSERT(max_finishing_splits >= max_splits && + max_finishing_splits < (8 * sizeof(unsigned))); + BOOST_STATIC_ASSERT(log_mean_bin_size >= 0); + BOOST_STATIC_ASSERT(log_finishing_count >= 0); + //if we can complete in one iteration, do so + //This first check allows the compiler to optimize never-executed code out + if (log_finishing_count < min_size) { + if (log_range <= min_size && log_range <= max_splits) { + //Return no smaller than a certain minimum limit + if (log_range <= log_finishing_count) + return typed_one << log_finishing_count; + return typed_one << log_range; + } + } + const unsigned base_iterations = max_splits - log_min_split_count; + //sum of n to n + x = ((x + 1) * (n + (n + x)))/2 + log_mean_bin_size + const unsigned base_range = + ((base_iterations + 1) * (max_splits + log_min_split_count))/2 + + log_mean_bin_size; + //Calculating the required number of iterations, and returning + //1 << (iteration_count + min_size) + if (log_range < base_range) { + unsigned result = log_min_split_count; + for (unsigned offset = min_size; offset < log_range; + offset += ++result); + //Preventing overflow; this situation shouldn't occur + if ((result + log_mean_bin_size) >= (8 * sizeof(size_t))) + return typed_one << ((8 * sizeof(size_t)) - 1); + return typed_one << (result + log_mean_bin_size); + } + //A quick division can calculate the worst-case runtime for larger ranges + unsigned remainder = log_range - base_range; + //the max_splits - 1 is used to calculate the ceiling of the division + unsigned bit_length = ((((max_splits - 1) + remainder)/max_splits) + + base_iterations + min_size); + //Preventing overflow; this situation shouldn't occur + if (bit_length >= (8 * sizeof(size_t))) + return typed_one << ((8 * sizeof(size_t)) - 1); + //n(log_range)/max_splits + C, optimizing worst-case performance + return typed_one << bit_length; + } + + // Resizes the bin cache and bin sizes, and initializes each bin size to 0. + // This generates the memory overhead to use in radix sorting. + template <class RandomAccessIter> + inline RandomAccessIter * + size_bins(size_t *bin_sizes, std::vector<RandomAccessIter> + &bin_cache, unsigned cache_offset, unsigned &cache_end, unsigned bin_count) + { + // Clear the bin sizes + for (size_t u = 0; u < bin_count; u++) + bin_sizes[u] = 0; + //Make sure there is space for the bins + cache_end = cache_offset + bin_count; + if (cache_end > bin_cache.size()) + bin_cache.resize(cache_end); + return &(bin_cache[cache_offset]); + } + } +} +} +} + +#endif diff --git a/boost/sort/spreadsort/detail/string_sort.hpp b/boost/sort/spreadsort/detail/string_sort.hpp index 582508fb7b..a548ebefa5 100644 --- a/boost/sort/spreadsort/detail/string_sort.hpp +++ b/boost/sort/spreadsort/detail/string_sort.hpp @@ -1,819 +1,819 @@ -// Details for a templated general-case hybrid-radix string_sort.
-
-// Copyright Steven J. Ross 2001 - 2014.
-// Distributed under the Boost Software License, Version 1.0.
-// (See accompanying file LICENSE_1_0.txt or copy at
-// http://www.boost.org/LICENSE_1_0.txt)
-
-// See http://www.boost.org/libs/sort for library home page.
-
-/*
-Some improvements suggested by:
-Phil Endecott and Frank Gennari
-*/
-
-#ifndef BOOST_SORT_SPREADSORT_DETAIL_SPREAD_SORT_HPP
-#define BOOST_SORT_SPREADSORT_DETAIL_SPREAD_SORT_HPP
-#include <algorithm>
-#include <vector>
-#include <cstring>
-#include <limits>
-#include <functional>
-#include <boost/static_assert.hpp>
-#include <boost/serialization/static_warning.hpp>
-#include <boost/utility/enable_if.hpp>
-#include <boost/sort/spreadsort/detail/constants.hpp>
-#include <boost/sort/spreadsort/detail/spreadsort_common.hpp>
-#include <boost/cstdint.hpp>
-
-namespace boost {
-namespace sort {
-namespace spreadsort {
- namespace detail {
- static const int max_step_size = 64;
-
- //Offsetting on identical characters. This function works a chunk of
- //characters at a time for cache efficiency and optimal worst-case
- //performance.
- template<class RandomAccessIter, class Unsigned_char_type>
- inline void
- update_offset(RandomAccessIter first, RandomAccessIter finish,
- size_t &char_offset)
- {
- const int char_size = sizeof(Unsigned_char_type);
- size_t nextOffset = char_offset;
- int step_size = max_step_size / char_size;
- while (true) {
- RandomAccessIter curr = first;
- do {
- //Ignore empties, but if the nextOffset would exceed the length or
- //not match, exit; we've found the last matching character
- //This will reduce the step_size if the current step doesn't match.
- if ((*curr).size() > char_offset) {
- if((*curr).size() <= (nextOffset + step_size)) {
- step_size = (*curr).size() - nextOffset - 1;
- if (step_size < 1) {
- char_offset = nextOffset;
- return;
- }
- }
- const int step_byte_size = step_size * char_size;
- if (memcmp(curr->data() + nextOffset, first->data() + nextOffset,
- step_byte_size) != 0) {
- if (step_size == 1) {
- char_offset = nextOffset;
- return;
- }
- step_size = (step_size > 4) ? 4 : 1;
- continue;
- }
- }
- ++curr;
- } while (curr != finish);
- nextOffset += step_size;
- }
- }
-
- //Offsetting on identical characters. This function works a character
- //at a time for optimal worst-case performance.
- template<class RandomAccessIter, class Get_char, class Get_length>
- inline void
- update_offset(RandomAccessIter first, RandomAccessIter finish,
- size_t &char_offset, Get_char getchar, Get_length length)
- {
- size_t nextOffset = char_offset;
- while (true) {
- RandomAccessIter curr = first;
- do {
- //ignore empties, but if the nextOffset would exceed the length or
- //not match, exit; we've found the last matching character
- if (length(*curr) > char_offset && (length(*curr) <= (nextOffset + 1)
- || getchar((*curr), nextOffset) != getchar((*first), nextOffset))) {
- char_offset = nextOffset;
- return;
- }
- } while (++curr != finish);
- ++nextOffset;
- }
- }
-
- //This comparison functor assumes strings are identical up to char_offset
- template<class Data_type, class Unsigned_char_type>
- struct offset_less_than {
- offset_less_than(size_t char_offset) : fchar_offset(char_offset){}
- inline bool operator()(const Data_type &x, const Data_type &y) const
- {
- size_t minSize = (std::min)(x.size(), y.size());
- for (size_t u = fchar_offset; u < minSize; ++u) {
- BOOST_STATIC_ASSERT(sizeof(x[u]) == sizeof(Unsigned_char_type));
- if (static_cast<Unsigned_char_type>(x[u]) !=
- static_cast<Unsigned_char_type>(y[u])) {
- return static_cast<Unsigned_char_type>(x[u]) <
- static_cast<Unsigned_char_type>(y[u]);
- }
- }
- return x.size() < y.size();
- }
- size_t fchar_offset;
- };
-
- //Compares strings assuming they are identical up to char_offset
- template<class Data_type, class Unsigned_char_type>
- struct offset_greater_than {
- offset_greater_than(size_t char_offset) : fchar_offset(char_offset){}
- inline bool operator()(const Data_type &x, const Data_type &y) const
- {
- size_t minSize = (std::min)(x.size(), y.size());
- for (size_t u = fchar_offset; u < minSize; ++u) {
- BOOST_STATIC_ASSERT(sizeof(x[u]) == sizeof(Unsigned_char_type));
- if (static_cast<Unsigned_char_type>(x[u]) !=
- static_cast<Unsigned_char_type>(y[u])) {
- return static_cast<Unsigned_char_type>(x[u]) >
- static_cast<Unsigned_char_type>(y[u]);
- }
- }
- return x.size() > y.size();
- }
- size_t fchar_offset;
- };
-
- //This comparison functor assumes strings are identical up to char_offset
- template<class Data_type, class Get_char, class Get_length>
- struct offset_char_less_than {
- offset_char_less_than(size_t char_offset) : fchar_offset(char_offset){}
- inline bool operator()(const Data_type &x, const Data_type &y) const
- {
- size_t minSize = (std::min)(length(x), length(y));
- for (size_t u = fchar_offset; u < minSize; ++u) {
- if (getchar(x, u) != getchar(y, u)) {
- return getchar(x, u) < getchar(y, u);
- }
- }
- return length(x) < length(y);
- }
- size_t fchar_offset;
- Get_char getchar;
- Get_length length;
- };
-
- //String sorting recursive implementation
- template <class RandomAccessIter, class Unsigned_char_type>
- inline void
- string_sort_rec(RandomAccessIter first, RandomAccessIter last,
- size_t char_offset,
- std::vector<RandomAccessIter> &bin_cache,
- unsigned cache_offset, size_t *bin_sizes)
- {
- typedef typename std::iterator_traits<RandomAccessIter>::value_type
- Data_type;
- //This section makes handling of long identical substrings much faster
- //with a mild average performance impact.
- //Iterate to the end of the empties. If all empty, return
- while ((*first).size() <= char_offset) {
- if (++first == last)
- return;
- }
- RandomAccessIter finish = last - 1;
- //Getting the last non-empty
- for (;(*finish).size() <= char_offset; --finish);
- ++finish;
- //Offsetting on identical characters. This section works
- //a few characters at a time for optimal worst-case performance.
- update_offset<RandomAccessIter, Unsigned_char_type>(first, finish,
- char_offset);
-
- const unsigned bin_count = (1 << (sizeof(Unsigned_char_type)*8));
- //Equal worst-case of radix and comparison is when bin_count = n*log(n).
- const unsigned max_size = bin_count;
- const unsigned membin_count = bin_count + 1;
- unsigned cache_end;
- RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset,
- cache_end, membin_count) + 1;
-
- //Calculating the size of each bin; this takes roughly 10% of runtime
- for (RandomAccessIter current = first; current != last; ++current) {
- if ((*current).size() <= char_offset) {
- bin_sizes[0]++;
- }
- else
- bin_sizes[static_cast<Unsigned_char_type>((*current)[char_offset])
- + 1]++;
- }
- //Assign the bin positions
- bin_cache[cache_offset] = first;
- for (unsigned u = 0; u < membin_count - 1; u++)
- bin_cache[cache_offset + u + 1] =
- bin_cache[cache_offset + u] + bin_sizes[u];
-
- //Swap into place
- RandomAccessIter next_bin_start = first;
- //handling empty bins
- RandomAccessIter * local_bin = &(bin_cache[cache_offset]);
- next_bin_start += bin_sizes[0];
- RandomAccessIter * target_bin;
- //Iterating over each element in the bin of empties
- for (RandomAccessIter current = *local_bin; current < next_bin_start;
- ++current) {
- //empties belong in this bin
- while ((*current).size() > char_offset) {
- target_bin =
- bins + static_cast<Unsigned_char_type>((*current)[char_offset]);
- iter_swap(current, (*target_bin)++);
- }
- }
- *local_bin = next_bin_start;
- //iterate backwards to find the last bin with elements in it
- //this saves iterations in multiple loops
- unsigned last_bin = bin_count - 1;
- for (; last_bin && !bin_sizes[last_bin + 1]; --last_bin);
- //This dominates runtime, mostly in the swap and bin lookups
- for (unsigned u = 0; u < last_bin; ++u) {
- local_bin = bins + u;
- next_bin_start += bin_sizes[u + 1];
- //Iterating over each element in this bin
- for (RandomAccessIter current = *local_bin; current < next_bin_start;
- ++current) {
- //Swapping into place until the correct element has been swapped in
- for (target_bin = bins + static_cast<Unsigned_char_type>
- ((*current)[char_offset]); target_bin != local_bin;
- target_bin = bins + static_cast<Unsigned_char_type>
- ((*current)[char_offset])) iter_swap(current, (*target_bin)++);
- }
- *local_bin = next_bin_start;
- }
- bins[last_bin] = last;
- //Recursing
- RandomAccessIter lastPos = bin_cache[cache_offset];
- //Skip this loop for empties
- for (unsigned u = cache_offset + 1; u < cache_offset + last_bin + 2;
- lastPos = bin_cache[u], ++u) {
- size_t count = bin_cache[u] - lastPos;
- //don't sort unless there are at least two items to Compare
- if (count < 2)
- continue;
- //using std::sort if its worst-case is better
- if (count < max_size)
- std::sort(lastPos, bin_cache[u],
- offset_less_than<Data_type, Unsigned_char_type>(char_offset + 1));
- else
- string_sort_rec<RandomAccessIter, Unsigned_char_type>(lastPos,
- bin_cache[u], char_offset + 1, bin_cache, cache_end, bin_sizes);
- }
- }
-
- //Sorts strings in reverse order, with empties at the end
- template <class RandomAccessIter, class Unsigned_char_type>
- inline void
- reverse_string_sort_rec(RandomAccessIter first, RandomAccessIter last,
- size_t char_offset,
- std::vector<RandomAccessIter> &bin_cache,
- unsigned cache_offset,
- size_t *bin_sizes)
- {
- typedef typename std::iterator_traits<RandomAccessIter>::value_type
- Data_type;
- //This section makes handling of long identical substrings much faster
- //with a mild average performance impact.
- RandomAccessIter curr = first;
- //Iterate to the end of the empties. If all empty, return
- while ((*curr).size() <= char_offset) {
- if (++curr == last)
- return;
- }
- //Getting the last non-empty
- while ((*(--last)).size() <= char_offset);
- ++last;
- //Offsetting on identical characters. This section works
- //a few characters at a time for optimal worst-case performance.
- update_offset<RandomAccessIter, Unsigned_char_type>(curr, last,
- char_offset);
- RandomAccessIter * target_bin;
-
- const unsigned bin_count = (1 << (sizeof(Unsigned_char_type)*8));
- //Equal worst-case of radix and comparison when bin_count = n*log(n).
- const unsigned max_size = bin_count;
- const unsigned membin_count = bin_count + 1;
- const unsigned max_bin = bin_count - 1;
- unsigned cache_end;
- RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset,
- cache_end, membin_count);
- RandomAccessIter * end_bin = &(bin_cache[cache_offset + max_bin]);
-
- //Calculating the size of each bin; this takes roughly 10% of runtime
- for (RandomAccessIter current = first; current != last; ++current) {
- if ((*current).size() <= char_offset) {
- bin_sizes[bin_count]++;
- }
- else
- bin_sizes[max_bin - static_cast<Unsigned_char_type>
- ((*current)[char_offset])]++;
- }
- //Assign the bin positions
- bin_cache[cache_offset] = first;
- for (unsigned u = 0; u < membin_count - 1; u++)
- bin_cache[cache_offset + u + 1] =
- bin_cache[cache_offset + u] + bin_sizes[u];
-
- //Swap into place
- RandomAccessIter next_bin_start = last;
- //handling empty bins
- RandomAccessIter * local_bin = &(bin_cache[cache_offset + bin_count]);
- RandomAccessIter lastFull = *local_bin;
- //Iterating over each element in the bin of empties
- for (RandomAccessIter current = *local_bin; current < next_bin_start;
- ++current) {
- //empties belong in this bin
- while ((*current).size() > char_offset) {
- target_bin =
- end_bin - static_cast<Unsigned_char_type>((*current)[char_offset]);
- iter_swap(current, (*target_bin)++);
- }
- }
- *local_bin = next_bin_start;
- next_bin_start = first;
- //iterate backwards to find the last non-empty bin
- //this saves iterations in multiple loops
- unsigned last_bin = max_bin;
- for (; last_bin && !bin_sizes[last_bin]; --last_bin);
- //This dominates runtime, mostly in the swap and bin lookups
- for (unsigned u = 0; u < last_bin; ++u) {
- local_bin = bins + u;
- next_bin_start += bin_sizes[u];
- //Iterating over each element in this bin
- for (RandomAccessIter current = *local_bin; current < next_bin_start;
- ++current) {
- //Swapping into place until the correct element has been swapped in
- for (target_bin =
- end_bin - static_cast<Unsigned_char_type>((*current)[char_offset]);
- target_bin != local_bin;
- target_bin =
- end_bin - static_cast<Unsigned_char_type>((*current)[char_offset]))
- iter_swap(current, (*target_bin)++);
- }
- *local_bin = next_bin_start;
- }
- bins[last_bin] = lastFull;
- //Recursing
- RandomAccessIter lastPos = first;
- //Skip this loop for empties
- for (unsigned u = cache_offset; u <= cache_offset + last_bin;
- lastPos = bin_cache[u], ++u) {
- size_t count = bin_cache[u] - lastPos;
- //don't sort unless there are at least two items to Compare
- if (count < 2)
- continue;
- //using std::sort if its worst-case is better
- if (count < max_size)
- std::sort(lastPos, bin_cache[u], offset_greater_than<Data_type,
- Unsigned_char_type>(char_offset + 1));
- else
- reverse_string_sort_rec<RandomAccessIter, Unsigned_char_type>
- (lastPos, bin_cache[u], char_offset + 1, bin_cache, cache_end, bin_sizes);
- }
- }
-
- //String sorting recursive implementation
- template <class RandomAccessIter, class Unsigned_char_type, class Get_char,
- class Get_length>
- inline void
- string_sort_rec(RandomAccessIter first, RandomAccessIter last,
- size_t char_offset, std::vector<RandomAccessIter> &bin_cache,
- unsigned cache_offset, size_t *bin_sizes,
- Get_char getchar, Get_length length)
- {
- typedef typename std::iterator_traits<RandomAccessIter>::value_type
- Data_type;
- //This section makes handling of long identical substrings much faster
- //with a mild average performance impact.
- //Iterate to the end of the empties. If all empty, return
- while (length(*first) <= char_offset) {
- if (++first == last)
- return;
- }
- RandomAccessIter finish = last - 1;
- //Getting the last non-empty
- for (;length(*finish) <= char_offset; --finish);
- ++finish;
- update_offset(first, finish, char_offset, getchar, length);
-
- const unsigned bin_count = (1 << (sizeof(Unsigned_char_type)*8));
- //Equal worst-case of radix and comparison is when bin_count = n*log(n).
- const unsigned max_size = bin_count;
- const unsigned membin_count = bin_count + 1;
- unsigned cache_end;
- RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset,
- cache_end, membin_count) + 1;
-
- //Calculating the size of each bin; this takes roughly 10% of runtime
- for (RandomAccessIter current = first; current != last; ++current) {
- if (length(*current) <= char_offset) {
- bin_sizes[0]++;
- }
- else
- bin_sizes[getchar((*current), char_offset) + 1]++;
- }
- //Assign the bin positions
- bin_cache[cache_offset] = first;
- for (unsigned u = 0; u < membin_count - 1; u++)
- bin_cache[cache_offset + u + 1] =
- bin_cache[cache_offset + u] + bin_sizes[u];
-
- //Swap into place
- RandomAccessIter next_bin_start = first;
- //handling empty bins
- RandomAccessIter * local_bin = &(bin_cache[cache_offset]);
- next_bin_start += bin_sizes[0];
- RandomAccessIter * target_bin;
- //Iterating over each element in the bin of empties
- for (RandomAccessIter current = *local_bin; current < next_bin_start;
- ++current) {
- //empties belong in this bin
- while (length(*current) > char_offset) {
- target_bin = bins + getchar((*current), char_offset);
- iter_swap(current, (*target_bin)++);
- }
- }
- *local_bin = next_bin_start;
- //iterate backwards to find the last bin with elements in it
- //this saves iterations in multiple loops
- unsigned last_bin = bin_count - 1;
- for (; last_bin && !bin_sizes[last_bin + 1]; --last_bin);
- //This dominates runtime, mostly in the swap and bin lookups
- for (unsigned ii = 0; ii < last_bin; ++ii) {
- local_bin = bins + ii;
- next_bin_start += bin_sizes[ii + 1];
- //Iterating over each element in this bin
- for (RandomAccessIter current = *local_bin; current < next_bin_start;
- ++current) {
- //Swapping into place until the correct element has been swapped in
- for (target_bin = bins + getchar((*current), char_offset);
- target_bin != local_bin;
- target_bin = bins + getchar((*current), char_offset))
- iter_swap(current, (*target_bin)++);
- }
- *local_bin = next_bin_start;
- }
- bins[last_bin] = last;
-
- //Recursing
- RandomAccessIter lastPos = bin_cache[cache_offset];
- //Skip this loop for empties
- for (unsigned u = cache_offset + 1; u < cache_offset + last_bin + 2;
- lastPos = bin_cache[u], ++u) {
- size_t count = bin_cache[u] - lastPos;
- //don't sort unless there are at least two items to Compare
- if (count < 2)
- continue;
- //using std::sort if its worst-case is better
- if (count < max_size)
- std::sort(lastPos, bin_cache[u], offset_char_less_than<Data_type,
- Get_char, Get_length>(char_offset + 1));
- else
- string_sort_rec<RandomAccessIter, Unsigned_char_type, Get_char,
- Get_length>(lastPos, bin_cache[u], char_offset + 1, bin_cache,
- cache_end, bin_sizes, getchar, length);
- }
- }
-
- //String sorting recursive implementation
- template <class RandomAccessIter, class Unsigned_char_type, class Get_char,
- class Get_length, class Compare>
- inline void
- string_sort_rec(RandomAccessIter first, RandomAccessIter last,
- size_t char_offset, std::vector<RandomAccessIter> &bin_cache,
- unsigned cache_offset, size_t *bin_sizes,
- Get_char getchar, Get_length length, Compare comp)
- {
- //This section makes handling of long identical substrings much faster
- //with a mild average performance impact.
- //Iterate to the end of the empties. If all empty, return
- while (length(*first) <= char_offset) {
- if (++first == last)
- return;
- }
- RandomAccessIter finish = last - 1;
- //Getting the last non-empty
- for (;length(*finish) <= char_offset; --finish);
- ++finish;
- update_offset(first, finish, char_offset, getchar, length);
-
- const unsigned bin_count = (1 << (sizeof(Unsigned_char_type)*8));
- //Equal worst-case of radix and comparison is when bin_count = n*log(n).
- const unsigned max_size = bin_count;
- const unsigned membin_count = bin_count + 1;
- unsigned cache_end;
- RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset,
- cache_end, membin_count) + 1;
-
- //Calculating the size of each bin; this takes roughly 10% of runtime
- for (RandomAccessIter current = first; current != last; ++current) {
- if (length(*current) <= char_offset) {
- bin_sizes[0]++;
- }
- else
- bin_sizes[getchar((*current), char_offset) + 1]++;
- }
- //Assign the bin positions
- bin_cache[cache_offset] = first;
- for (unsigned u = 0; u < membin_count - 1; u++)
- bin_cache[cache_offset + u + 1] =
- bin_cache[cache_offset + u] + bin_sizes[u];
-
- //Swap into place
- RandomAccessIter next_bin_start = first;
- //handling empty bins
- RandomAccessIter * local_bin = &(bin_cache[cache_offset]);
- next_bin_start += bin_sizes[0];
- RandomAccessIter * target_bin;
- //Iterating over each element in the bin of empties
- for (RandomAccessIter current = *local_bin; current < next_bin_start;
- ++current) {
- //empties belong in this bin
- while (length(*current) > char_offset) {
- target_bin = bins + getchar((*current), char_offset);
- iter_swap(current, (*target_bin)++);
- }
- }
- *local_bin = next_bin_start;
- //iterate backwards to find the last bin with elements in it
- //this saves iterations in multiple loops
- unsigned last_bin = bin_count - 1;
- for (; last_bin && !bin_sizes[last_bin + 1]; --last_bin);
- //This dominates runtime, mostly in the swap and bin lookups
- for (unsigned u = 0; u < last_bin; ++u) {
- local_bin = bins + u;
- next_bin_start += bin_sizes[u + 1];
- //Iterating over each element in this bin
- for (RandomAccessIter current = *local_bin; current < next_bin_start;
- ++current) {
- //Swapping into place until the correct element has been swapped in
- for (target_bin = bins + getchar((*current), char_offset);
- target_bin != local_bin;
- target_bin = bins + getchar((*current), char_offset))
- iter_swap(current, (*target_bin)++);
- }
- *local_bin = next_bin_start;
- }
- bins[last_bin] = last;
-
- //Recursing
- RandomAccessIter lastPos = bin_cache[cache_offset];
- //Skip this loop for empties
- for (unsigned u = cache_offset + 1; u < cache_offset + last_bin + 2;
- lastPos = bin_cache[u], ++u) {
- size_t count = bin_cache[u] - lastPos;
- //don't sort unless there are at least two items to Compare
- if (count < 2)
- continue;
- //using std::sort if its worst-case is better
- if (count < max_size)
- std::sort(lastPos, bin_cache[u], comp);
- else
- string_sort_rec<RandomAccessIter, Unsigned_char_type, Get_char,
- Get_length, Compare>
- (lastPos, bin_cache[u], char_offset + 1, bin_cache, cache_end,
- bin_sizes, getchar, length, comp);
- }
- }
-
- //Sorts strings in reverse order, with empties at the end
- template <class RandomAccessIter, class Unsigned_char_type, class Get_char,
- class Get_length, class Compare>
- inline void
- reverse_string_sort_rec(RandomAccessIter first, RandomAccessIter last,
- size_t char_offset, std::vector<RandomAccessIter> &bin_cache,
- unsigned cache_offset, size_t *bin_sizes,
- Get_char getchar, Get_length length, Compare comp)
- {
- //This section makes handling of long identical substrings much faster
- //with a mild average performance impact.
- RandomAccessIter curr = first;
- //Iterate to the end of the empties. If all empty, return
- while (length(*curr) <= char_offset) {
- if (++curr == last)
- return;
- }
- //Getting the last non-empty
- while (length(*(--last)) <= char_offset);
- ++last;
- //Offsetting on identical characters. This section works
- //a character at a time for optimal worst-case performance.
- update_offset(curr, last, char_offset, getchar, length);
-
- const unsigned bin_count = (1 << (sizeof(Unsigned_char_type)*8));
- //Equal worst-case of radix and comparison is when bin_count = n*log(n).
- const unsigned max_size = bin_count;
- const unsigned membin_count = bin_count + 1;
- const unsigned max_bin = bin_count - 1;
- unsigned cache_end;
- RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset,
- cache_end, membin_count);
- RandomAccessIter *end_bin = &(bin_cache[cache_offset + max_bin]);
-
- //Calculating the size of each bin; this takes roughly 10% of runtime
- for (RandomAccessIter current = first; current != last; ++current) {
- if (length(*current) <= char_offset) {
- bin_sizes[bin_count]++;
- }
- else
- bin_sizes[max_bin - getchar((*current), char_offset)]++;
- }
- //Assign the bin positions
- bin_cache[cache_offset] = first;
- for (unsigned u = 0; u < membin_count - 1; u++)
- bin_cache[cache_offset + u + 1] =
- bin_cache[cache_offset + u] + bin_sizes[u];
-
- //Swap into place
- RandomAccessIter next_bin_start = last;
- //handling empty bins
- RandomAccessIter * local_bin = &(bin_cache[cache_offset + bin_count]);
- RandomAccessIter lastFull = *local_bin;
- RandomAccessIter * target_bin;
- //Iterating over each element in the bin of empties
- for (RandomAccessIter current = *local_bin; current < next_bin_start;
- ++current) {
- //empties belong in this bin
- while (length(*current) > char_offset) {
- target_bin = end_bin - getchar((*current), char_offset);
- iter_swap(current, (*target_bin)++);
- }
- }
- *local_bin = next_bin_start;
- next_bin_start = first;
- //iterate backwards to find the last bin with elements in it
- //this saves iterations in multiple loops
- unsigned last_bin = max_bin;
- for (; last_bin && !bin_sizes[last_bin]; --last_bin);
- //This dominates runtime, mostly in the swap and bin lookups
- for (unsigned u = 0; u < last_bin; ++u) {
- local_bin = bins + u;
- next_bin_start += bin_sizes[u];
- //Iterating over each element in this bin
- for (RandomAccessIter current = *local_bin; current < next_bin_start;
- ++current) {
- //Swapping into place until the correct element has been swapped in
- for (target_bin = end_bin - getchar((*current), char_offset);
- target_bin != local_bin;
- target_bin = end_bin - getchar((*current), char_offset))
- iter_swap(current, (*target_bin)++);
- }
- *local_bin = next_bin_start;
- }
- bins[last_bin] = lastFull;
- //Recursing
- RandomAccessIter lastPos = first;
- //Skip this loop for empties
- for (unsigned u = cache_offset; u <= cache_offset + last_bin;
- lastPos = bin_cache[u], ++u) {
- size_t count = bin_cache[u] - lastPos;
- //don't sort unless there are at least two items to Compare
- if (count < 2)
- continue;
- //using std::sort if its worst-case is better
- if (count < max_size)
- std::sort(lastPos, bin_cache[u], comp);
- else
- reverse_string_sort_rec<RandomAccessIter, Unsigned_char_type,
- Get_char, Get_length, Compare>
- (lastPos, bin_cache[u], char_offset + 1, bin_cache, cache_end,
- bin_sizes, getchar, length, comp);
- }
- }
-
- //Holds the bin vector and makes the initial recursive call
- template <class RandomAccessIter, class Unsigned_char_type>
- inline typename boost::enable_if_c< sizeof(Unsigned_char_type) <= 2, void
- >::type
- string_sort(RandomAccessIter first, RandomAccessIter last,
- Unsigned_char_type)
- {
- size_t bin_sizes[(1 << (8 * sizeof(Unsigned_char_type))) + 1];
- std::vector<RandomAccessIter> bin_cache;
- string_sort_rec<RandomAccessIter, Unsigned_char_type>
- (first, last, 0, bin_cache, 0, bin_sizes);
- }
-
- template <class RandomAccessIter, class Unsigned_char_type>
- inline typename boost::disable_if_c< sizeof(Unsigned_char_type) <= 2, void
- >::type
- string_sort(RandomAccessIter first, RandomAccessIter last,
- Unsigned_char_type)
- {
- //Warning that we're using std::sort, even though string_sort was called
- BOOST_STATIC_WARNING( sizeof(Unsigned_char_type) <= 2 );
- std::sort(first, last);
- }
-
- //Holds the bin vector and makes the initial recursive call
- template <class RandomAccessIter, class Unsigned_char_type>
- inline typename boost::enable_if_c< sizeof(Unsigned_char_type) <= 2, void
- >::type
- reverse_string_sort(RandomAccessIter first, RandomAccessIter last,
- Unsigned_char_type)
- {
- size_t bin_sizes[(1 << (8 * sizeof(Unsigned_char_type))) + 1];
- std::vector<RandomAccessIter> bin_cache;
- reverse_string_sort_rec<RandomAccessIter, Unsigned_char_type>
- (first, last, 0, bin_cache, 0, bin_sizes);
- }
-
- template <class RandomAccessIter, class Unsigned_char_type>
- inline typename boost::disable_if_c< sizeof(Unsigned_char_type) <= 2, void
- >::type
- reverse_string_sort(RandomAccessIter first, RandomAccessIter last,
- Unsigned_char_type)
- {
- typedef typename std::iterator_traits<RandomAccessIter>::value_type
- Data_type;
- //Warning that we're using std::sort, even though string_sort was called
- BOOST_STATIC_WARNING( sizeof(Unsigned_char_type) <= 2 );
- std::sort(first, last, std::greater<Data_type>());
- }
-
- //Holds the bin vector and makes the initial recursive call
- template <class RandomAccessIter, class Get_char, class Get_length,
- class Unsigned_char_type>
- inline typename boost::enable_if_c< sizeof(Unsigned_char_type) <= 2, void
- >::type
- string_sort(RandomAccessIter first, RandomAccessIter last,
- Get_char getchar, Get_length length, Unsigned_char_type)
- {
- size_t bin_sizes[(1 << (8 * sizeof(Unsigned_char_type))) + 1];
- std::vector<RandomAccessIter> bin_cache;
- string_sort_rec<RandomAccessIter, Unsigned_char_type, Get_char,
- Get_length>(first, last, 0, bin_cache, 0, bin_sizes, getchar, length);
- }
-
- template <class RandomAccessIter, class Get_char, class Get_length,
- class Unsigned_char_type>
- inline typename boost::disable_if_c< sizeof(Unsigned_char_type) <= 2, void
- >::type
- string_sort(RandomAccessIter first, RandomAccessIter last,
- Get_char getchar, Get_length length, Unsigned_char_type)
- {
- //Warning that we're using std::sort, even though string_sort was called
- BOOST_STATIC_WARNING( sizeof(Unsigned_char_type) <= 2 );
- std::sort(first, last);
- }
-
- //Holds the bin vector and makes the initial recursive call
- template <class RandomAccessIter, class Get_char, class Get_length,
- class Compare, class Unsigned_char_type>
- inline typename boost::enable_if_c< sizeof(Unsigned_char_type) <= 2, void
- >::type
- string_sort(RandomAccessIter first, RandomAccessIter last,
- Get_char getchar, Get_length length, Compare comp, Unsigned_char_type)
- {
- size_t bin_sizes[(1 << (8 * sizeof(Unsigned_char_type))) + 1];
- std::vector<RandomAccessIter> bin_cache;
- string_sort_rec<RandomAccessIter, Unsigned_char_type, Get_char
- , Get_length, Compare>
- (first, last, 0, bin_cache, 0, bin_sizes, getchar, length, comp);
- }
-
- //disable_if_c was refusing to compile, so rewrote to use enable_if_c
- template <class RandomAccessIter, class Get_char, class Get_length,
- class Compare, class Unsigned_char_type>
- inline typename boost::enable_if_c< (sizeof(Unsigned_char_type) > 2), void
- >::type
- string_sort(RandomAccessIter first, RandomAccessIter last,
- Get_char getchar, Get_length length, Compare comp, Unsigned_char_type)
- {
- //Warning that we're using std::sort, even though string_sort was called
- BOOST_STATIC_WARNING( sizeof(Unsigned_char_type) <= 2 );
- std::sort(first, last, comp);
- }
-
- //Holds the bin vector and makes the initial recursive call
- template <class RandomAccessIter, class Get_char, class Get_length,
- class Compare, class Unsigned_char_type>
- inline typename boost::enable_if_c< sizeof(Unsigned_char_type) <= 2, void
- >::type
- reverse_string_sort(RandomAccessIter first, RandomAccessIter last,
- Get_char getchar, Get_length length, Compare comp, Unsigned_char_type)
- {
- size_t bin_sizes[(1 << (8 * sizeof(Unsigned_char_type))) + 1];
- std::vector<RandomAccessIter> bin_cache;
- reverse_string_sort_rec<RandomAccessIter, Unsigned_char_type, Get_char,
- Get_length, Compare>
- (first, last, 0, bin_cache, 0, bin_sizes, getchar, length, comp);
- }
-
- template <class RandomAccessIter, class Get_char, class Get_length,
- class Compare, class Unsigned_char_type>
- inline typename boost::disable_if_c< sizeof(Unsigned_char_type) <= 2, void
- >::type
- reverse_string_sort(RandomAccessIter first, RandomAccessIter last,
- Get_char getchar, Get_length length, Compare comp, Unsigned_char_type)
- {
- //Warning that we're using std::sort, even though string_sort was called
- BOOST_STATIC_WARNING( sizeof(Unsigned_char_type) <= 2 );
- std::sort(first, last, comp);
- }
- }
-}
-}
-}
-
-#endif
+// Details for a templated general-case hybrid-radix string_sort. + +// Copyright Steven J. Ross 2001 - 2014. +// Distributed under the Boost Software License, Version 1.0. +// (See accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) + +// See http://www.boost.org/libs/sort for library home page. + +/* +Some improvements suggested by: +Phil Endecott and Frank Gennari +*/ + +#ifndef BOOST_SORT_SPREADSORT_DETAIL_SPREAD_SORT_HPP +#define BOOST_SORT_SPREADSORT_DETAIL_SPREAD_SORT_HPP +#include <algorithm> +#include <vector> +#include <cstring> +#include <limits> +#include <functional> +#include <boost/static_assert.hpp> +#include <boost/serialization/static_warning.hpp> +#include <boost/utility/enable_if.hpp> +#include <boost/sort/spreadsort/detail/constants.hpp> +#include <boost/sort/spreadsort/detail/spreadsort_common.hpp> +#include <boost/cstdint.hpp> + +namespace boost { +namespace sort { +namespace spreadsort { + namespace detail { + static const int max_step_size = 64; + + //Offsetting on identical characters. This function works a chunk of + //characters at a time for cache efficiency and optimal worst-case + //performance. + template<class RandomAccessIter, class Unsigned_char_type> + inline void + update_offset(RandomAccessIter first, RandomAccessIter finish, + size_t &char_offset) + { + const int char_size = sizeof(Unsigned_char_type); + size_t nextOffset = char_offset; + int step_size = max_step_size / char_size; + while (true) { + RandomAccessIter curr = first; + do { + //Ignore empties, but if the nextOffset would exceed the length or + //not match, exit; we've found the last matching character + //This will reduce the step_size if the current step doesn't match. + if ((*curr).size() > char_offset) { + if((*curr).size() <= (nextOffset + step_size)) { + step_size = (*curr).size() - nextOffset - 1; + if (step_size < 1) { + char_offset = nextOffset; + return; + } + } + const int step_byte_size = step_size * char_size; + if (memcmp(curr->data() + nextOffset, first->data() + nextOffset, + step_byte_size) != 0) { + if (step_size == 1) { + char_offset = nextOffset; + return; + } + step_size = (step_size > 4) ? 4 : 1; + continue; + } + } + ++curr; + } while (curr != finish); + nextOffset += step_size; + } + } + + //Offsetting on identical characters. This function works a character + //at a time for optimal worst-case performance. + template<class RandomAccessIter, class Get_char, class Get_length> + inline void + update_offset(RandomAccessIter first, RandomAccessIter finish, + size_t &char_offset, Get_char get_character, Get_length length) + { + size_t nextOffset = char_offset; + while (true) { + RandomAccessIter curr = first; + do { + //ignore empties, but if the nextOffset would exceed the length or + //not match, exit; we've found the last matching character + if (length(*curr) > char_offset && (length(*curr) <= (nextOffset + 1) + || get_character((*curr), nextOffset) != get_character((*first), nextOffset))) { + char_offset = nextOffset; + return; + } + } while (++curr != finish); + ++nextOffset; + } + } + + //This comparison functor assumes strings are identical up to char_offset + template<class Data_type, class Unsigned_char_type> + struct offset_less_than { + offset_less_than(size_t char_offset) : fchar_offset(char_offset){} + inline bool operator()(const Data_type &x, const Data_type &y) const + { + size_t minSize = (std::min)(x.size(), y.size()); + for (size_t u = fchar_offset; u < minSize; ++u) { + BOOST_STATIC_ASSERT(sizeof(x[u]) == sizeof(Unsigned_char_type)); + if (static_cast<Unsigned_char_type>(x[u]) != + static_cast<Unsigned_char_type>(y[u])) { + return static_cast<Unsigned_char_type>(x[u]) < + static_cast<Unsigned_char_type>(y[u]); + } + } + return x.size() < y.size(); + } + size_t fchar_offset; + }; + + //Compares strings assuming they are identical up to char_offset + template<class Data_type, class Unsigned_char_type> + struct offset_greater_than { + offset_greater_than(size_t char_offset) : fchar_offset(char_offset){} + inline bool operator()(const Data_type &x, const Data_type &y) const + { + size_t minSize = (std::min)(x.size(), y.size()); + for (size_t u = fchar_offset; u < minSize; ++u) { + BOOST_STATIC_ASSERT(sizeof(x[u]) == sizeof(Unsigned_char_type)); + if (static_cast<Unsigned_char_type>(x[u]) != + static_cast<Unsigned_char_type>(y[u])) { + return static_cast<Unsigned_char_type>(x[u]) > + static_cast<Unsigned_char_type>(y[u]); + } + } + return x.size() > y.size(); + } + size_t fchar_offset; + }; + + //This comparison functor assumes strings are identical up to char_offset + template<class Data_type, class Get_char, class Get_length> + struct offset_char_less_than { + offset_char_less_than(size_t char_offset) : fchar_offset(char_offset){} + inline bool operator()(const Data_type &x, const Data_type &y) const + { + size_t minSize = (std::min)(length(x), length(y)); + for (size_t u = fchar_offset; u < minSize; ++u) { + if (get_character(x, u) != get_character(y, u)) { + return get_character(x, u) < get_character(y, u); + } + } + return length(x) < length(y); + } + size_t fchar_offset; + Get_char get_character; + Get_length length; + }; + + //String sorting recursive implementation + template <class RandomAccessIter, class Unsigned_char_type> + inline void + string_sort_rec(RandomAccessIter first, RandomAccessIter last, + size_t char_offset, + std::vector<RandomAccessIter> &bin_cache, + unsigned cache_offset, size_t *bin_sizes) + { + typedef typename std::iterator_traits<RandomAccessIter>::value_type + Data_type; + //This section makes handling of long identical substrings much faster + //with a mild average performance impact. + //Iterate to the end of the empties. If all empty, return + while ((*first).size() <= char_offset) { + if (++first == last) + return; + } + RandomAccessIter finish = last - 1; + //Getting the last non-empty + for (;(*finish).size() <= char_offset; --finish); + ++finish; + //Offsetting on identical characters. This section works + //a few characters at a time for optimal worst-case performance. + update_offset<RandomAccessIter, Unsigned_char_type>(first, finish, + char_offset); + + const unsigned bin_count = (1 << (sizeof(Unsigned_char_type)*8)); + //Equal worst-case of radix and comparison is when bin_count = n*log(n). + const unsigned max_size = bin_count; + const unsigned membin_count = bin_count + 1; + unsigned cache_end; + RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset, + cache_end, membin_count) + 1; + + //Calculating the size of each bin; this takes roughly 10% of runtime + for (RandomAccessIter current = first; current != last; ++current) { + if ((*current).size() <= char_offset) { + bin_sizes[0]++; + } + else + bin_sizes[static_cast<Unsigned_char_type>((*current)[char_offset]) + + 1]++; + } + //Assign the bin positions + bin_cache[cache_offset] = first; + for (unsigned u = 0; u < membin_count - 1; u++) + bin_cache[cache_offset + u + 1] = + bin_cache[cache_offset + u] + bin_sizes[u]; + + //Swap into place + RandomAccessIter next_bin_start = first; + //handling empty bins + RandomAccessIter * local_bin = &(bin_cache[cache_offset]); + next_bin_start += bin_sizes[0]; + RandomAccessIter * target_bin; + //Iterating over each element in the bin of empties + for (RandomAccessIter current = *local_bin; current < next_bin_start; + ++current) { + //empties belong in this bin + while ((*current).size() > char_offset) { + target_bin = + bins + static_cast<Unsigned_char_type>((*current)[char_offset]); + iter_swap(current, (*target_bin)++); + } + } + *local_bin = next_bin_start; + //iterate backwards to find the last bin with elements in it + //this saves iterations in multiple loops + unsigned last_bin = bin_count - 1; + for (; last_bin && !bin_sizes[last_bin + 1]; --last_bin); + //This dominates runtime, mostly in the swap and bin lookups + for (unsigned u = 0; u < last_bin; ++u) { + local_bin = bins + u; + next_bin_start += bin_sizes[u + 1]; + //Iterating over each element in this bin + for (RandomAccessIter current = *local_bin; current < next_bin_start; + ++current) { + //Swapping into place until the correct element has been swapped in + for (target_bin = bins + static_cast<Unsigned_char_type> + ((*current)[char_offset]); target_bin != local_bin; + target_bin = bins + static_cast<Unsigned_char_type> + ((*current)[char_offset])) iter_swap(current, (*target_bin)++); + } + *local_bin = next_bin_start; + } + bins[last_bin] = last; + //Recursing + RandomAccessIter lastPos = bin_cache[cache_offset]; + //Skip this loop for empties + for (unsigned u = cache_offset + 1; u < cache_offset + last_bin + 2; + lastPos = bin_cache[u], ++u) { + size_t count = bin_cache[u] - lastPos; + //don't sort unless there are at least two items to Compare + if (count < 2) + continue; + //using std::sort if its worst-case is better + if (count < max_size) + std::sort(lastPos, bin_cache[u], + offset_less_than<Data_type, Unsigned_char_type>(char_offset + 1)); + else + string_sort_rec<RandomAccessIter, Unsigned_char_type>(lastPos, + bin_cache[u], char_offset + 1, bin_cache, cache_end, bin_sizes); + } + } + + //Sorts strings in reverse order, with empties at the end + template <class RandomAccessIter, class Unsigned_char_type> + inline void + reverse_string_sort_rec(RandomAccessIter first, RandomAccessIter last, + size_t char_offset, + std::vector<RandomAccessIter> &bin_cache, + unsigned cache_offset, + size_t *bin_sizes) + { + typedef typename std::iterator_traits<RandomAccessIter>::value_type + Data_type; + //This section makes handling of long identical substrings much faster + //with a mild average performance impact. + RandomAccessIter curr = first; + //Iterate to the end of the empties. If all empty, return + while ((*curr).size() <= char_offset) { + if (++curr == last) + return; + } + //Getting the last non-empty + while ((*(--last)).size() <= char_offset); + ++last; + //Offsetting on identical characters. This section works + //a few characters at a time for optimal worst-case performance. + update_offset<RandomAccessIter, Unsigned_char_type>(curr, last, + char_offset); + RandomAccessIter * target_bin; + + const unsigned bin_count = (1 << (sizeof(Unsigned_char_type)*8)); + //Equal worst-case of radix and comparison when bin_count = n*log(n). + const unsigned max_size = bin_count; + const unsigned membin_count = bin_count + 1; + const unsigned max_bin = bin_count - 1; + unsigned cache_end; + RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset, + cache_end, membin_count); + RandomAccessIter * end_bin = &(bin_cache[cache_offset + max_bin]); + + //Calculating the size of each bin; this takes roughly 10% of runtime + for (RandomAccessIter current = first; current != last; ++current) { + if ((*current).size() <= char_offset) { + bin_sizes[bin_count]++; + } + else + bin_sizes[max_bin - static_cast<Unsigned_char_type> + ((*current)[char_offset])]++; + } + //Assign the bin positions + bin_cache[cache_offset] = first; + for (unsigned u = 0; u < membin_count - 1; u++) + bin_cache[cache_offset + u + 1] = + bin_cache[cache_offset + u] + bin_sizes[u]; + + //Swap into place + RandomAccessIter next_bin_start = last; + //handling empty bins + RandomAccessIter * local_bin = &(bin_cache[cache_offset + bin_count]); + RandomAccessIter lastFull = *local_bin; + //Iterating over each element in the bin of empties + for (RandomAccessIter current = *local_bin; current < next_bin_start; + ++current) { + //empties belong in this bin + while ((*current).size() > char_offset) { + target_bin = + end_bin - static_cast<Unsigned_char_type>((*current)[char_offset]); + iter_swap(current, (*target_bin)++); + } + } + *local_bin = next_bin_start; + next_bin_start = first; + //iterate backwards to find the last non-empty bin + //this saves iterations in multiple loops + unsigned last_bin = max_bin; + for (; last_bin && !bin_sizes[last_bin]; --last_bin); + //This dominates runtime, mostly in the swap and bin lookups + for (unsigned u = 0; u < last_bin; ++u) { + local_bin = bins + u; + next_bin_start += bin_sizes[u]; + //Iterating over each element in this bin + for (RandomAccessIter current = *local_bin; current < next_bin_start; + ++current) { + //Swapping into place until the correct element has been swapped in + for (target_bin = + end_bin - static_cast<Unsigned_char_type>((*current)[char_offset]); + target_bin != local_bin; + target_bin = + end_bin - static_cast<Unsigned_char_type>((*current)[char_offset])) + iter_swap(current, (*target_bin)++); + } + *local_bin = next_bin_start; + } + bins[last_bin] = lastFull; + //Recursing + RandomAccessIter lastPos = first; + //Skip this loop for empties + for (unsigned u = cache_offset; u <= cache_offset + last_bin; + lastPos = bin_cache[u], ++u) { + size_t count = bin_cache[u] - lastPos; + //don't sort unless there are at least two items to Compare + if (count < 2) + continue; + //using std::sort if its worst-case is better + if (count < max_size) + std::sort(lastPos, bin_cache[u], offset_greater_than<Data_type, + Unsigned_char_type>(char_offset + 1)); + else + reverse_string_sort_rec<RandomAccessIter, Unsigned_char_type> + (lastPos, bin_cache[u], char_offset + 1, bin_cache, cache_end, bin_sizes); + } + } + + //String sorting recursive implementation + template <class RandomAccessIter, class Unsigned_char_type, class Get_char, + class Get_length> + inline void + string_sort_rec(RandomAccessIter first, RandomAccessIter last, + size_t char_offset, std::vector<RandomAccessIter> &bin_cache, + unsigned cache_offset, size_t *bin_sizes, + Get_char get_character, Get_length length) + { + typedef typename std::iterator_traits<RandomAccessIter>::value_type + Data_type; + //This section makes handling of long identical substrings much faster + //with a mild average performance impact. + //Iterate to the end of the empties. If all empty, return + while (length(*first) <= char_offset) { + if (++first == last) + return; + } + RandomAccessIter finish = last - 1; + //Getting the last non-empty + for (;length(*finish) <= char_offset; --finish); + ++finish; + update_offset(first, finish, char_offset, get_character, length); + + const unsigned bin_count = (1 << (sizeof(Unsigned_char_type)*8)); + //Equal worst-case of radix and comparison is when bin_count = n*log(n). + const unsigned max_size = bin_count; + const unsigned membin_count = bin_count + 1; + unsigned cache_end; + RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset, + cache_end, membin_count) + 1; + + //Calculating the size of each bin; this takes roughly 10% of runtime + for (RandomAccessIter current = first; current != last; ++current) { + if (length(*current) <= char_offset) { + bin_sizes[0]++; + } + else + bin_sizes[get_character((*current), char_offset) + 1]++; + } + //Assign the bin positions + bin_cache[cache_offset] = first; + for (unsigned u = 0; u < membin_count - 1; u++) + bin_cache[cache_offset + u + 1] = + bin_cache[cache_offset + u] + bin_sizes[u]; + + //Swap into place + RandomAccessIter next_bin_start = first; + //handling empty bins + RandomAccessIter * local_bin = &(bin_cache[cache_offset]); + next_bin_start += bin_sizes[0]; + RandomAccessIter * target_bin; + //Iterating over each element in the bin of empties + for (RandomAccessIter current = *local_bin; current < next_bin_start; + ++current) { + //empties belong in this bin + while (length(*current) > char_offset) { + target_bin = bins + get_character((*current), char_offset); + iter_swap(current, (*target_bin)++); + } + } + *local_bin = next_bin_start; + //iterate backwards to find the last bin with elements in it + //this saves iterations in multiple loops + unsigned last_bin = bin_count - 1; + for (; last_bin && !bin_sizes[last_bin + 1]; --last_bin); + //This dominates runtime, mostly in the swap and bin lookups + for (unsigned ii = 0; ii < last_bin; ++ii) { + local_bin = bins + ii; + next_bin_start += bin_sizes[ii + 1]; + //Iterating over each element in this bin + for (RandomAccessIter current = *local_bin; current < next_bin_start; + ++current) { + //Swapping into place until the correct element has been swapped in + for (target_bin = bins + get_character((*current), char_offset); + target_bin != local_bin; + target_bin = bins + get_character((*current), char_offset)) + iter_swap(current, (*target_bin)++); + } + *local_bin = next_bin_start; + } + bins[last_bin] = last; + + //Recursing + RandomAccessIter lastPos = bin_cache[cache_offset]; + //Skip this loop for empties + for (unsigned u = cache_offset + 1; u < cache_offset + last_bin + 2; + lastPos = bin_cache[u], ++u) { + size_t count = bin_cache[u] - lastPos; + //don't sort unless there are at least two items to Compare + if (count < 2) + continue; + //using std::sort if its worst-case is better + if (count < max_size) + std::sort(lastPos, bin_cache[u], offset_char_less_than<Data_type, + Get_char, Get_length>(char_offset + 1)); + else + string_sort_rec<RandomAccessIter, Unsigned_char_type, Get_char, + Get_length>(lastPos, bin_cache[u], char_offset + 1, bin_cache, + cache_end, bin_sizes, get_character, length); + } + } + + //String sorting recursive implementation + template <class RandomAccessIter, class Unsigned_char_type, class Get_char, + class Get_length, class Compare> + inline void + string_sort_rec(RandomAccessIter first, RandomAccessIter last, + size_t char_offset, std::vector<RandomAccessIter> &bin_cache, + unsigned cache_offset, size_t *bin_sizes, + Get_char get_character, Get_length length, Compare comp) + { + //This section makes handling of long identical substrings much faster + //with a mild average performance impact. + //Iterate to the end of the empties. If all empty, return + while (length(*first) <= char_offset) { + if (++first == last) + return; + } + RandomAccessIter finish = last - 1; + //Getting the last non-empty + for (;length(*finish) <= char_offset; --finish); + ++finish; + update_offset(first, finish, char_offset, get_character, length); + + const unsigned bin_count = (1 << (sizeof(Unsigned_char_type)*8)); + //Equal worst-case of radix and comparison is when bin_count = n*log(n). + const unsigned max_size = bin_count; + const unsigned membin_count = bin_count + 1; + unsigned cache_end; + RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset, + cache_end, membin_count) + 1; + + //Calculating the size of each bin; this takes roughly 10% of runtime + for (RandomAccessIter current = first; current != last; ++current) { + if (length(*current) <= char_offset) { + bin_sizes[0]++; + } + else + bin_sizes[get_character((*current), char_offset) + 1]++; + } + //Assign the bin positions + bin_cache[cache_offset] = first; + for (unsigned u = 0; u < membin_count - 1; u++) + bin_cache[cache_offset + u + 1] = + bin_cache[cache_offset + u] + bin_sizes[u]; + + //Swap into place + RandomAccessIter next_bin_start = first; + //handling empty bins + RandomAccessIter * local_bin = &(bin_cache[cache_offset]); + next_bin_start += bin_sizes[0]; + RandomAccessIter * target_bin; + //Iterating over each element in the bin of empties + for (RandomAccessIter current = *local_bin; current < next_bin_start; + ++current) { + //empties belong in this bin + while (length(*current) > char_offset) { + target_bin = bins + get_character((*current), char_offset); + iter_swap(current, (*target_bin)++); + } + } + *local_bin = next_bin_start; + //iterate backwards to find the last bin with elements in it + //this saves iterations in multiple loops + unsigned last_bin = bin_count - 1; + for (; last_bin && !bin_sizes[last_bin + 1]; --last_bin); + //This dominates runtime, mostly in the swap and bin lookups + for (unsigned u = 0; u < last_bin; ++u) { + local_bin = bins + u; + next_bin_start += bin_sizes[u + 1]; + //Iterating over each element in this bin + for (RandomAccessIter current = *local_bin; current < next_bin_start; + ++current) { + //Swapping into place until the correct element has been swapped in + for (target_bin = bins + get_character((*current), char_offset); + target_bin != local_bin; + target_bin = bins + get_character((*current), char_offset)) + iter_swap(current, (*target_bin)++); + } + *local_bin = next_bin_start; + } + bins[last_bin] = last; + + //Recursing + RandomAccessIter lastPos = bin_cache[cache_offset]; + //Skip this loop for empties + for (unsigned u = cache_offset + 1; u < cache_offset + last_bin + 2; + lastPos = bin_cache[u], ++u) { + size_t count = bin_cache[u] - lastPos; + //don't sort unless there are at least two items to Compare + if (count < 2) + continue; + //using std::sort if its worst-case is better + if (count < max_size) + std::sort(lastPos, bin_cache[u], comp); + else + string_sort_rec<RandomAccessIter, Unsigned_char_type, Get_char, + Get_length, Compare> + (lastPos, bin_cache[u], char_offset + 1, bin_cache, cache_end, + bin_sizes, get_character, length, comp); + } + } + + //Sorts strings in reverse order, with empties at the end + template <class RandomAccessIter, class Unsigned_char_type, class Get_char, + class Get_length, class Compare> + inline void + reverse_string_sort_rec(RandomAccessIter first, RandomAccessIter last, + size_t char_offset, std::vector<RandomAccessIter> &bin_cache, + unsigned cache_offset, size_t *bin_sizes, + Get_char get_character, Get_length length, Compare comp) + { + //This section makes handling of long identical substrings much faster + //with a mild average performance impact. + RandomAccessIter curr = first; + //Iterate to the end of the empties. If all empty, return + while (length(*curr) <= char_offset) { + if (++curr == last) + return; + } + //Getting the last non-empty + while (length(*(--last)) <= char_offset); + ++last; + //Offsetting on identical characters. This section works + //a character at a time for optimal worst-case performance. + update_offset(curr, last, char_offset, get_character, length); + + const unsigned bin_count = (1 << (sizeof(Unsigned_char_type)*8)); + //Equal worst-case of radix and comparison is when bin_count = n*log(n). + const unsigned max_size = bin_count; + const unsigned membin_count = bin_count + 1; + const unsigned max_bin = bin_count - 1; + unsigned cache_end; + RandomAccessIter * bins = size_bins(bin_sizes, bin_cache, cache_offset, + cache_end, membin_count); + RandomAccessIter *end_bin = &(bin_cache[cache_offset + max_bin]); + + //Calculating the size of each bin; this takes roughly 10% of runtime + for (RandomAccessIter current = first; current != last; ++current) { + if (length(*current) <= char_offset) { + bin_sizes[bin_count]++; + } + else + bin_sizes[max_bin - get_character((*current), char_offset)]++; + } + //Assign the bin positions + bin_cache[cache_offset] = first; + for (unsigned u = 0; u < membin_count - 1; u++) + bin_cache[cache_offset + u + 1] = + bin_cache[cache_offset + u] + bin_sizes[u]; + + //Swap into place + RandomAccessIter next_bin_start = last; + //handling empty bins + RandomAccessIter * local_bin = &(bin_cache[cache_offset + bin_count]); + RandomAccessIter lastFull = *local_bin; + RandomAccessIter * target_bin; + //Iterating over each element in the bin of empties + for (RandomAccessIter current = *local_bin; current < next_bin_start; + ++current) { + //empties belong in this bin + while (length(*current) > char_offset) { + target_bin = end_bin - get_character((*current), char_offset); + iter_swap(current, (*target_bin)++); + } + } + *local_bin = next_bin_start; + next_bin_start = first; + //iterate backwards to find the last bin with elements in it + //this saves iterations in multiple loops + unsigned last_bin = max_bin; + for (; last_bin && !bin_sizes[last_bin]; --last_bin); + //This dominates runtime, mostly in the swap and bin lookups + for (unsigned u = 0; u < last_bin; ++u) { + local_bin = bins + u; + next_bin_start += bin_sizes[u]; + //Iterating over each element in this bin + for (RandomAccessIter current = *local_bin; current < next_bin_start; + ++current) { + //Swapping into place until the correct element has been swapped in + for (target_bin = end_bin - get_character((*current), char_offset); + target_bin != local_bin; + target_bin = end_bin - get_character((*current), char_offset)) + iter_swap(current, (*target_bin)++); + } + *local_bin = next_bin_start; + } + bins[last_bin] = lastFull; + //Recursing + RandomAccessIter lastPos = first; + //Skip this loop for empties + for (unsigned u = cache_offset; u <= cache_offset + last_bin; + lastPos = bin_cache[u], ++u) { + size_t count = bin_cache[u] - lastPos; + //don't sort unless there are at least two items to Compare + if (count < 2) + continue; + //using std::sort if its worst-case is better + if (count < max_size) + std::sort(lastPos, bin_cache[u], comp); + else + reverse_string_sort_rec<RandomAccessIter, Unsigned_char_type, + Get_char, Get_length, Compare> + (lastPos, bin_cache[u], char_offset + 1, bin_cache, cache_end, + bin_sizes, get_character, length, comp); + } + } + + //Holds the bin vector and makes the initial recursive call + template <class RandomAccessIter, class Unsigned_char_type> + inline typename boost::enable_if_c< sizeof(Unsigned_char_type) <= 2, void + >::type + string_sort(RandomAccessIter first, RandomAccessIter last, + Unsigned_char_type) + { + size_t bin_sizes[(1 << (8 * sizeof(Unsigned_char_type))) + 1]; + std::vector<RandomAccessIter> bin_cache; + string_sort_rec<RandomAccessIter, Unsigned_char_type> + (first, last, 0, bin_cache, 0, bin_sizes); + } + + template <class RandomAccessIter, class Unsigned_char_type> + inline typename boost::disable_if_c< sizeof(Unsigned_char_type) <= 2, void + >::type + string_sort(RandomAccessIter first, RandomAccessIter last, + Unsigned_char_type) + { + //Warning that we're using std::sort, even though string_sort was called + BOOST_STATIC_WARNING( sizeof(Unsigned_char_type) <= 2 ); + std::sort(first, last); + } + + //Holds the bin vector and makes the initial recursive call + template <class RandomAccessIter, class Unsigned_char_type> + inline typename boost::enable_if_c< sizeof(Unsigned_char_type) <= 2, void + >::type + reverse_string_sort(RandomAccessIter first, RandomAccessIter last, + Unsigned_char_type) + { + size_t bin_sizes[(1 << (8 * sizeof(Unsigned_char_type))) + 1]; + std::vector<RandomAccessIter> bin_cache; + reverse_string_sort_rec<RandomAccessIter, Unsigned_char_type> + (first, last, 0, bin_cache, 0, bin_sizes); + } + + template <class RandomAccessIter, class Unsigned_char_type> + inline typename boost::disable_if_c< sizeof(Unsigned_char_type) <= 2, void + >::type + reverse_string_sort(RandomAccessIter first, RandomAccessIter last, + Unsigned_char_type) + { + typedef typename std::iterator_traits<RandomAccessIter>::value_type + Data_type; + //Warning that we're using std::sort, even though string_sort was called + BOOST_STATIC_WARNING( sizeof(Unsigned_char_type) <= 2 ); + std::sort(first, last, std::greater<Data_type>()); + } + + //Holds the bin vector and makes the initial recursive call + template <class RandomAccessIter, class Get_char, class Get_length, + class Unsigned_char_type> + inline typename boost::enable_if_c< sizeof(Unsigned_char_type) <= 2, void + >::type + string_sort(RandomAccessIter first, RandomAccessIter last, + Get_char get_character, Get_length length, Unsigned_char_type) + { + size_t bin_sizes[(1 << (8 * sizeof(Unsigned_char_type))) + 1]; + std::vector<RandomAccessIter> bin_cache; + string_sort_rec<RandomAccessIter, Unsigned_char_type, Get_char, + Get_length>(first, last, 0, bin_cache, 0, bin_sizes, get_character, length); + } + + template <class RandomAccessIter, class Get_char, class Get_length, + class Unsigned_char_type> + inline typename boost::disable_if_c< sizeof(Unsigned_char_type) <= 2, void + >::type + string_sort(RandomAccessIter first, RandomAccessIter last, + Get_char get_character, Get_length length, Unsigned_char_type) + { + //Warning that we're using std::sort, even though string_sort was called + BOOST_STATIC_WARNING( sizeof(Unsigned_char_type) <= 2 ); + std::sort(first, last); + } + + //Holds the bin vector and makes the initial recursive call + template <class RandomAccessIter, class Get_char, class Get_length, + class Compare, class Unsigned_char_type> + inline typename boost::enable_if_c< sizeof(Unsigned_char_type) <= 2, void + >::type + string_sort(RandomAccessIter first, RandomAccessIter last, + Get_char get_character, Get_length length, Compare comp, Unsigned_char_type) + { + size_t bin_sizes[(1 << (8 * sizeof(Unsigned_char_type))) + 1]; + std::vector<RandomAccessIter> bin_cache; + string_sort_rec<RandomAccessIter, Unsigned_char_type, Get_char + , Get_length, Compare> + (first, last, 0, bin_cache, 0, bin_sizes, get_character, length, comp); + } + + //disable_if_c was refusing to compile, so rewrote to use enable_if_c + template <class RandomAccessIter, class Get_char, class Get_length, + class Compare, class Unsigned_char_type> + inline typename boost::enable_if_c< (sizeof(Unsigned_char_type) > 2), void + >::type + string_sort(RandomAccessIter first, RandomAccessIter last, + Get_char get_character, Get_length length, Compare comp, Unsigned_char_type) + { + //Warning that we're using std::sort, even though string_sort was called + BOOST_STATIC_WARNING( sizeof(Unsigned_char_type) <= 2 ); + std::sort(first, last, comp); + } + + //Holds the bin vector and makes the initial recursive call + template <class RandomAccessIter, class Get_char, class Get_length, + class Compare, class Unsigned_char_type> + inline typename boost::enable_if_c< sizeof(Unsigned_char_type) <= 2, void + >::type + reverse_string_sort(RandomAccessIter first, RandomAccessIter last, + Get_char get_character, Get_length length, Compare comp, Unsigned_char_type) + { + size_t bin_sizes[(1 << (8 * sizeof(Unsigned_char_type))) + 1]; + std::vector<RandomAccessIter> bin_cache; + reverse_string_sort_rec<RandomAccessIter, Unsigned_char_type, Get_char, + Get_length, Compare> + (first, last, 0, bin_cache, 0, bin_sizes, get_character, length, comp); + } + + template <class RandomAccessIter, class Get_char, class Get_length, + class Compare, class Unsigned_char_type> + inline typename boost::disable_if_c< sizeof(Unsigned_char_type) <= 2, void + >::type + reverse_string_sort(RandomAccessIter first, RandomAccessIter last, + Get_char get_character, Get_length length, Compare comp, Unsigned_char_type) + { + //Warning that we're using std::sort, even though string_sort was called + BOOST_STATIC_WARNING( sizeof(Unsigned_char_type) <= 2 ); + std::sort(first, last, comp); + } + } +} +} +} + +#endif |