2 * libsortnetwork - src/sn_network.c
3 * Copyright (C) 2008-2010 Florian octo Forster
5 * This library is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU Lesser General Public License as published by
7 * the Free Software Foundation; either version 2.1 of the License, or (at
8 * your option) any later version.
10 * This library is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
15 * You should have received a copy of the GNU Lesser General Public License
16 * along with this library; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 * Florian octo Forster <ff at octo.it>
23 #ifndef _ISOC99_SOURCE
24 # define _ISOC99_SOURCE
26 #ifndef _POSIX_C_SOURCE
27 # define _POSIX_C_SOURCE 200112L
31 # define DPRINTF(...) fprintf (stderr, "sn_network: " __VA_ARGS__)
33 # define DPRINTF(...) /**/
44 #include "sn_network.h"
45 #include "sn_random.h"
47 sn_network_t *sn_network_create (int inputs_num) /* {{{ */
51 n = (sn_network_t *) malloc (sizeof (sn_network_t));
54 memset (n, '\0', sizeof (sn_network_t));
56 n->inputs_num = inputs_num;
59 } /* }}} sn_network_t *sn_network_create */
61 void sn_network_destroy (sn_network_t *n) /* {{{ */
66 if (n->stages != NULL)
69 for (i = 0; i < n->stages_num; i++)
71 sn_stage_destroy (n->stages[i]);
79 } /* }}} void sn_network_destroy */
81 sn_network_t *sn_network_create_odd_even_mergesort (int inputs_num) /* {{{ */
85 n = sn_network_create (inputs_num);
87 assert (inputs_num > 0);
100 s = sn_stage_create (/* depth = */ 0);
101 sn_stage_comparator_add (s, &c);
102 sn_network_stage_add (n, s);
108 sn_network_t *n_left;
109 sn_network_t *n_right;
113 inputs_left = inputs_num / 2;
114 inputs_right = inputs_num - inputs_left;
116 n_left = sn_network_create_odd_even_mergesort (inputs_left);
120 n_right = sn_network_create_odd_even_mergesort (inputs_right);
123 sn_network_destroy (n_left);
127 n = sn_network_combine_odd_even_merge (n_left, n_right);
129 sn_network_destroy (n_left);
130 sn_network_destroy (n_right);
133 sn_network_compress (n);
137 } /* }}} sn_network_t *sn_network_create_odd_even_mergesort */
139 sn_network_t *sn_network_create_bitonic_mergesort (int inputs_num) /* {{{ */
143 assert (inputs_num > 0);
146 return (sn_network_create (inputs_num));
152 n = sn_network_create (inputs_num);
154 memset (&c, 0, sizeof (c));
158 sn_network_comparator_add (n, &c);
164 sn_network_t *n_left;
165 sn_network_t *n_right;
169 inputs_left = inputs_num / 2;
170 inputs_right = inputs_num - inputs_left;
172 n_left = sn_network_create_bitonic_mergesort (inputs_left);
176 if (inputs_left != inputs_right)
177 n_right = sn_network_create_bitonic_mergesort (inputs_right);
182 sn_network_destroy (n_left);
186 n = sn_network_combine_bitonic_merge (n_left, n_right);
188 if (n_left != n_right)
189 sn_network_destroy (n_right);
190 sn_network_destroy (n_left);
193 sn_network_compress (n);
197 } /* }}} sn_network_t *sn_network_create_bitonic_mergesort */
199 static int sn_network_create_pairwise_internal (sn_network_t *n, /* {{{ */
200 int *inputs, int inputs_num)
203 int inputs_copy[inputs_num];
206 for (i = 1; i < inputs_num; i += 2)
208 sn_comparator_t *c = sn_comparator_create (inputs[i-1], inputs[i]);
209 sn_network_comparator_add (n, c);
210 sn_comparator_destroy (c);
216 /* Sort "pairs" recursively. Like with odd-even mergesort, odd and even lines
217 * are handled recursively and later reunited. */
218 for (i = 0; i < inputs_num; i += 2)
219 inputs_copy[(int) (i / 2)] = inputs[i];
220 /* Recursive call #1 with first set of lines */
221 sn_network_create_pairwise_internal (n, inputs_copy,
222 (int) ((inputs_num + 1) / 2));
224 for (i = 1; i < inputs_num; i += 2)
225 inputs_copy[(int) (i / 2)] = inputs[i];
226 /* Recursive call #2 with second set of lines */
227 sn_network_create_pairwise_internal (n, inputs_copy,
228 (int) (inputs_num/ 2));
230 /* m is the "amplitude" of the sorted pairs. This is a bit tricky to read due
231 * to different indices being used in the paper, unfortunately. */
235 for (i = 1; (i + (m - 1)) < inputs_num; i += 2)
238 int right = i + (m - 1);
241 assert (left < right);
242 c = sn_comparator_create (inputs[left], inputs[right]);
243 sn_network_comparator_add (n, c);
244 sn_comparator_destroy (c);
248 } /* while (m > 1) */
251 } /* }}} int sn_network_create_pairwise_internal */
253 sn_network_t *sn_network_create_pairwise (int inputs_num) /* {{{ */
255 sn_network_t *n = sn_network_create (inputs_num);
256 int inputs[inputs_num];
262 for (i = 0; i < inputs_num; i++)
265 sn_network_create_pairwise_internal (n, inputs, inputs_num);
266 sn_network_compress (n);
269 } /* }}} sn_network_t *sn_network_create_pairwise */
271 int sn_network_network_add (sn_network_t *n, sn_network_t *other) /* {{{ */
276 if ((n == NULL) || (other == NULL))
279 stages_num = n->stages_num + other->stages_num;
280 if (stages_num <= n->stages_num)
283 tmp = realloc (n->stages, sizeof (*n->stages) * stages_num);
288 memcpy (n->stages + n->stages_num, other->stages,
289 sizeof (*other->stages) * other->stages_num);
290 n->stages_num = stages_num;
292 free (other->stages);
296 } /* }}} int sn_network_network_add */
298 int sn_network_stage_add (sn_network_t *n, sn_stage_t *s) /* {{{ */
302 if ((n == NULL) || (s == NULL))
305 temp = (sn_stage_t **) realloc (n->stages, (n->stages_num + 1)
306 * sizeof (sn_stage_t *));
311 SN_STAGE_DEPTH (s) = n->stages_num;
312 n->stages[n->stages_num] = s;
316 } /* }}} int sn_network_stage_add */
318 int sn_network_stage_remove (sn_network_t *n, int s_num) /* {{{ */
320 int nmemb = n->stages_num - (s_num + 1);
323 if ((n == NULL) || (s_num >= n->stages_num))
326 sn_stage_destroy (n->stages[s_num]);
327 n->stages[s_num] = NULL;
331 memmove (n->stages + s_num, n->stages + (s_num + 1),
332 nmemb * sizeof (sn_stage_t *));
333 n->stages[n->stages_num - 1] = NULL;
337 /* Free the unused memory */
338 if (n->stages_num == 0)
345 temp = (sn_stage_t **) realloc (n->stages,
346 n->stages_num * sizeof (sn_stage_t *));
353 } /* }}} int sn_network_stage_remove */
355 sn_network_t *sn_network_clone (const sn_network_t *n) /* {{{ */
357 sn_network_t *n_copy;
360 n_copy = sn_network_create (n->inputs_num);
364 for (i = 0; i < n->stages_num; i++)
369 s = sn_stage_clone (n->stages[i]);
373 status = sn_network_stage_add (n_copy, s);
378 if (i < n->stages_num)
380 sn_network_destroy (n_copy);
385 } /* }}} sn_network_t *sn_network_clone */
387 int sn_network_comparator_add (sn_network_t *n, /* {{{ */
388 const sn_comparator_t *c)
392 if ((n == NULL) || (c == NULL))
395 if (n->stages_num > 0)
397 s = n->stages[n->stages_num - 1];
399 if (sn_stage_comparator_check_conflict (s, c) == 0)
401 sn_stage_comparator_add (s, c);
406 s = sn_stage_create (n->stages_num);
407 sn_stage_comparator_add (s, c);
408 sn_network_stage_add (n, s);
411 } /* }}} int sn_network_comparator_add */
413 int sn_network_get_comparator_num (const sn_network_t *n) /* {{{ */
422 for (i = 0; i < n->stages_num; i++)
423 num += n->stages[i]->comparators_num;
426 } /* }}} int sn_network_get_comparator_num */
428 int sn_network_show (sn_network_t *n) /* {{{ */
432 for (i = 0; i < n->stages_num; i++)
433 sn_stage_show (n->stages[i]);
436 } /* }}} int sn_network_show */
438 int sn_network_invert (sn_network_t *n) /* {{{ */
445 for (i = 0; i < n->stages_num; i++)
446 sn_stage_invert (n->stages[i]);
449 } /* }}} int sn_network_invert */
451 int sn_network_shift (sn_network_t *n, int sw) /* {{{ */
455 if ((n == NULL) || (sw < 0))
461 for (i = 0; i < n->stages_num; i++)
462 sn_stage_shift (n->stages[i], sw, SN_NETWORK_INPUT_NUM (n));
465 } /* }}} int sn_network_shift */
467 int sn_network_compress (sn_network_t *n) /* {{{ */
473 for (i = 1; i < n->stages_num; i++)
479 for (j = 0; j < SN_STAGE_COMP_NUM (s); j++)
481 sn_comparator_t *c = SN_STAGE_COMP_GET (s, j);
484 for (k = i - 1; k >= 0; k--)
488 conflict = sn_stage_comparator_check_conflict (n->stages[k], c);
503 sn_stage_comparator_add (n->stages[move_to], c);
504 sn_stage_comparator_remove (s, j);
510 while ((n->stages_num > 0)
511 && (SN_STAGE_COMP_NUM (n->stages[n->stages_num - 1]) == 0))
512 sn_network_stage_remove (n, n->stages_num - 1);
515 } /* }}} int sn_network_compress */
517 int sn_network_normalize (sn_network_t *n) /* {{{ */
521 for (i = 0; i < n->stages_num; i++)
528 for (j = 0; j < SN_STAGE_COMP_NUM (s); j++)
534 c = SN_STAGE_COMP_GET (s, j);
543 for (k = i; k < n->stages_num; k++)
544 sn_stage_swap (n->stages[k], min, max);
549 } /* for (j = 0 .. #comparators) */
550 } /* for (i = n->stages_num - 1 .. 0) */
553 } /* }}} int sn_network_normalize */
555 int sn_network_remove_input (sn_network_t *n, int input) /* {{{ */
559 if ((n == NULL) || (input < 0) || (input >= n->inputs_num))
562 for (i = 0; i < n->stages_num; i++)
563 sn_stage_remove_input (n->stages[i], input);
568 } /* }}} int sn_network_remove_input */
570 int sn_network_cut_at (sn_network_t *n, int input, /* {{{ */
571 enum sn_network_cut_dir_e dir)
574 int position = input;
576 for (i = 0; i < n->stages_num; i++)
582 new_position = sn_stage_cut_at (s, position, dir);
584 if (position != new_position)
588 for (j = 0; j < i; j++)
589 sn_stage_swap (n->stages[j], position, new_position);
592 position = new_position;
595 assert (((dir == DIR_MIN) && (position == 0))
596 || ((dir == DIR_MAX) && (position == (n->inputs_num - 1))));
598 sn_network_remove_input (n, position);
601 } /* }}} int sn_network_cut_at */
603 int sn_network_cut (sn_network_t *n, int *mask) /* {{{ */
608 for (i = 0; i < n->stages_num; i++)
610 sn_stage_t *s = n->stages[i];
612 sn_stage_cut (s, mask, n->stages);
615 /* Use a copy of this member since it will be updated by
616 * sn_network_remove_input(). */
617 inputs_num = n->inputs_num;
618 for (i = 0; i < inputs_num; i++)
621 sn_network_remove_input (n, 0);
622 else if (mask[i] > 0)
623 sn_network_remove_input (n, n->inputs_num - 1);
627 } /* }}} int sn_network_cut */
629 /* sn_network_concatenate
631 * `Glues' two networks together, resulting in a comparator network with twice
632 * as many inputs but one that doesn't really sort anymore. It produces a
633 * bitonic sequence, though, that can be used by the mergers below. */
634 static sn_network_t *sn_network_concatenate (sn_network_t *n0, /* {{{ */
642 stages_num = (n0->stages_num > n1->stages_num)
646 n = sn_network_create (n0->inputs_num + n1->inputs_num);
650 for (i = 0; i < stages_num; i++)
652 sn_stage_t *s = sn_stage_create (i);
654 if (i < n0->stages_num)
655 for (j = 0; j < SN_STAGE_COMP_NUM (n0->stages[i]); j++)
657 sn_comparator_t *c = SN_STAGE_COMP_GET (n0->stages[i], j);
658 sn_stage_comparator_add (s, c);
661 if (i < n1->stages_num)
662 for (j = 0; j < SN_STAGE_COMP_NUM (n1->stages[i]); j++)
664 sn_comparator_t *c_orig = SN_STAGE_COMP_GET (n1->stages[i], j);
665 sn_comparator_t c_copy;
667 SN_COMP_MIN(&c_copy) = SN_COMP_MIN(c_orig) + n0->inputs_num;
668 SN_COMP_MAX(&c_copy) = SN_COMP_MAX(c_orig) + n0->inputs_num;
670 sn_stage_comparator_add (s, &c_copy);
673 sn_network_stage_add (n, s);
677 } /* }}} sn_network_t *sn_network_concatenate */
679 static int sn_network_add_bitonic_merger (sn_network_t *n, /* {{{ */
680 int *indizes, int indizes_num)
684 if (indizes_num <= 1)
689 int even_indizes[indizes_num];
690 int even_indizes_num;
691 int odd_indizes[indizes_num];
694 even_indizes_num = (indizes_num + 1) / 2;
695 odd_indizes_num = indizes_num / 2;
697 for (i = 0; i < even_indizes_num; i++)
698 even_indizes[i] = indizes[2 * i];
699 for (i = 0; i < odd_indizes_num; i++)
700 odd_indizes[i] = indizes[(2 * i) + 1];
702 sn_network_add_bitonic_merger (n, even_indizes, even_indizes_num);
703 sn_network_add_bitonic_merger (n, odd_indizes, odd_indizes_num);
706 for (i = 1; i < indizes_num; i += 2)
710 memset (&c, 0, sizeof (c));
711 c.min = indizes[i - 1];
714 sn_network_comparator_add (n, &c);
718 } /* }}} int sn_network_add_bitonic_merger */
720 static int sn_network_add_odd_even_merger (sn_network_t *n, /* {{{ */
721 int *indizes_left, int indizes_left_num,
722 int *indizes_right, int indizes_right_num)
724 int tmp_left[indizes_left_num];
726 int tmp_right[indizes_left_num];
732 if ((indizes_left_num == 0) || (indizes_right_num == 0))
736 else if ((indizes_left_num == 1) && (indizes_right_num == 1))
741 c.min = *indizes_left;
742 c.max = *indizes_right;
744 s = sn_stage_create (n->stages_num);
748 sn_stage_comparator_add (s, &c);
749 sn_network_stage_add (n, s);
754 /* Merge odd sequences */
755 tmp_left_num = (indizes_left_num + 1) / 2;
756 for (i = 0; i < tmp_left_num; i++)
757 tmp_left[i] = indizes_left[2 * i];
759 tmp_right_num = (indizes_right_num + 1) / 2;
760 for (i = 0; i < tmp_right_num; i++)
761 tmp_right[i] = indizes_right[2 * i];
763 sn_network_add_odd_even_merger (n,
764 tmp_left, tmp_left_num,
765 tmp_right, tmp_right_num);
767 /* Merge even sequences */
768 tmp_left_num = indizes_left_num / 2;
769 for (i = 0; i < tmp_left_num; i++)
770 tmp_left[i] = indizes_left[(2 * i) + 1];
772 tmp_right_num = indizes_right_num / 2;
773 for (i = 0; i < tmp_right_num; i++)
774 tmp_right[i] = indizes_right[(2 * i) + 1];
776 sn_network_add_odd_even_merger (n,
777 tmp_left, tmp_left_num,
778 tmp_right, tmp_right_num);
780 /* Apply ``comparison-interchange'' operations. */
781 s = sn_stage_create (n->stages_num);
783 max_index = indizes_left_num + indizes_right_num;
784 if ((max_index % 2) == 0)
789 for (i = 1; i <= max_index; i += 2)
793 if (i < indizes_left_num)
794 c.min = indizes_left[i];
796 c.min = indizes_right[i - indizes_left_num];
798 if ((i + 1) < indizes_left_num)
799 c.max = indizes_left[i + 1];
801 c.max = indizes_right[i + 1 - indizes_left_num];
803 sn_stage_comparator_add (s, &c);
806 sn_network_stage_add (n, s);
809 } /* }}} int sn_network_add_odd_even_merger */
811 sn_network_t *sn_network_combine_bitonic_merge (sn_network_t *n0, /* {{{ */
814 sn_network_t *n0_clone;
816 int indizes_num = SN_NETWORK_INPUT_NUM (n0) + SN_NETWORK_INPUT_NUM (n1);
817 int indizes[indizes_num];
820 /* We need to invert n0, because the sequence must be
821 * z_1 >= z_2 >= ... >= z_k <= z_{k+1} <= ... <= z_p
822 * and NOT the other way around! Otherwise the comparators added in
823 * sn_network_add_bitonic_merger() from comparing (z_0,z_1), (z_2,z_3), ...
824 * to comparing ..., (z_{n-4},z_{n-3}), (z_{n-2},z_{n-1}), i.e. bound to the
825 * end of the list, possibly leaving z_0 uncompared. */
826 n0_clone = sn_network_clone (n0);
827 if (n0_clone == NULL)
829 sn_network_invert (n0_clone);
831 n = sn_network_concatenate (n0_clone, n1);
834 sn_network_destroy (n0_clone);
836 for (i = 0; i < indizes_num; i++)
839 sn_network_add_bitonic_merger (n, indizes, indizes_num);
842 } /* }}} sn_network_t *sn_network_combine_bitonic_merge */
844 sn_network_t *sn_network_combine_odd_even_merge (sn_network_t *n0, /* {{{ */
848 int indizes_left[n0->inputs_num];
849 int indizes_left_num;
850 int indizes_right[n1->inputs_num];
851 int indizes_right_num;
855 indizes_left_num = n0->inputs_num;
856 indizes_right_num = n1->inputs_num;
857 for (i = 0; i < indizes_left_num; i++)
859 for (i = 0; i < indizes_right_num; i++)
860 indizes_right[i] = indizes_left_num + i;
862 n = sn_network_concatenate (n0, n1);
866 status = sn_network_add_odd_even_merger (n,
867 indizes_left, indizes_left_num,
868 indizes_right, indizes_right_num);
871 sn_network_destroy (n);
875 sn_network_compress (n);
877 } /* }}} sn_network_t *sn_network_combine_odd_even_merge */
879 sn_network_t *sn_network_combine (sn_network_t *n0, /* {{{ */
882 return (sn_network_combine_odd_even_merge (n0, n1));
883 } /* }}} sn_network_t *sn_network_combine */
885 int sn_network_sort (sn_network_t *n, int *values) /* {{{ */
891 for (i = 0; i < n->stages_num; i++)
893 status = sn_stage_sort (n->stages[i], values);
899 } /* }}} int sn_network_sort */
901 int sn_network_brute_force_check (sn_network_t *n) /* {{{ */
903 int test_pattern[n->inputs_num];
904 int values[n->inputs_num];
908 memset (test_pattern, 0, sizeof (test_pattern));
914 /* Copy the current pattern and let the network sort it */
915 memcpy (values, test_pattern, sizeof (values));
916 status = sn_network_sort (n, values);
920 /* Check if the array is now sorted. */
921 previous = values[0];
922 for (i = 1; i < n->inputs_num; i++)
924 if (previous > values[i])
926 previous = values[i];
929 /* Generate the next test pattern */
931 for (i = 0; i < n->inputs_num; i++)
933 if (test_pattern[i] == 0)
946 /* Break out of the while loop if we tested all possible patterns */
951 /* All tests successfull */
953 } /* }}} int sn_network_brute_force_check */
955 sn_network_t *sn_network_read (FILE *fh) /* {{{ */
962 while (fgets (buffer, sizeof (buffer), fh) != NULL)
964 char *str_key = buffer;
965 char *str_value = NULL;
966 int buffer_len = strlen (buffer);
968 while ((buffer_len > 0) && ((buffer[buffer_len - 1] == '\n')
969 || (buffer[buffer_len - 1] == '\r')))
972 buffer[buffer_len] = '\0';
977 str_value = strchr (buffer, ':');
978 if (str_value == NULL)
980 printf ("Cannot parse line: %s\n", buffer);
984 *str_value = '\0'; str_value++;
985 while ((*str_value != '\0') && (isspace (*str_value) != 0))
988 if (strcasecmp ("Inputs", str_key) == 0)
989 opt_inputs = atoi (str_value);
991 printf ("Unknown key: %s\n", str_key);
992 } /* while (fgets) */
997 n = sn_network_create (opt_inputs);
1003 s = sn_stage_read (fh);
1007 sn_network_stage_add (n, s);
1010 if (SN_NETWORK_STAGE_NUM (n) < 1)
1012 sn_network_destroy (n);
1017 } /* }}} sn_network_t *sn_network_read */
1019 sn_network_t *sn_network_read_file (const char *file) /* {{{ */
1024 fh = fopen (file, "r");
1028 n = sn_network_read (fh);
1033 } /* }}} sn_network_t *sn_network_read_file */
1035 int sn_network_write (sn_network_t *n, FILE *fh) /* {{{ */
1039 fprintf (fh, "Inputs: %i\n", n->inputs_num);
1042 for (i = 0; i < n->stages_num; i++)
1043 sn_stage_write (n->stages[i], fh);
1046 } /* }}} int sn_network_write */
1048 int sn_network_write_file (sn_network_t *n, const char *file) /* {{{ */
1053 fh = fopen (file, "w");
1057 status = sn_network_write (n, fh);
1062 } /* }}} int sn_network_write_file */
1064 int sn_network_serialize (sn_network_t *n, char **ret_buffer, /* {{{ */
1065 size_t *ret_buffer_size)
1072 buffer = *ret_buffer;
1073 buffer_size = *ret_buffer_size;
1075 #define SNPRINTF_OR_FAIL(...) \
1076 status = snprintf (buffer, buffer_size, __VA_ARGS__); \
1077 if ((status < 1) || (((size_t) status) >= buffer_size)) \
1080 buffer_size -= status;
1082 SNPRINTF_OR_FAIL ("Inputs: %i\r\n\r\n", n->inputs_num);
1084 for (i = 0; i < n->stages_num; i++)
1086 status = sn_stage_serialize (n->stages[i], &buffer, &buffer_size);
1091 *ret_buffer = buffer;
1092 *ret_buffer_size = buffer_size;
1094 } /* }}} int sn_network_serialize */
1096 sn_network_t *sn_network_unserialize (char *buffer, /* {{{ */
1102 if (buffer_size == 0)
1105 /* Read options first */
1106 while (buffer_size > 0)
1115 endptr = strchr (buffer, '\n');
1122 line_len = strlen (line);
1124 if ((line_len > 0) && (line[line_len - 1] == '\r'))
1126 line[line_len - 1] = 0;
1134 str_value = strchr (line, ':');
1135 if (str_value == NULL)
1137 printf ("Cannot parse line: %s\n", line);
1141 *str_value = '\0'; str_value++;
1142 while ((*str_value != '\0') && (isspace (*str_value) != 0))
1145 if (strcasecmp ("Inputs", str_key) == 0)
1146 opt_inputs = atoi (str_value);
1148 printf ("Unknown key: %s\n", str_key);
1149 } /* while (fgets) */
1154 n = sn_network_create (opt_inputs);
1160 s = sn_stage_unserialize (&buffer, &buffer_size);
1164 sn_network_stage_add (n, s);
1167 if (SN_NETWORK_STAGE_NUM (n) < 1)
1169 sn_network_destroy (n);
1174 } /* }}} sn_network_t *sn_network_unserialize */
1176 /* vim: set sw=2 sts=2 et fdm=marker : */