6 #include "heuristical.h"
7 #include "html_dumper.h"
10 #include "pbqp_edge.h"
11 #include "pbqp_edge_t.h"
12 #include "pbqp_node.h"
13 #include "pbqp_node_t.h"
16 static pbqp_edge **edge_bucket;
17 static pbqp_node **node_buckets[4];
18 static pbqp_node **reduced_bucket = NULL;
19 static int buckets_filled = 0;
25 /* Forward declarations. */
26 static void apply_Brute_Force(pbqp *pbqp);
28 static void insert_into_edge_bucket(pbqp_edge *edge)
30 if (edge_bucket_contains(edge_bucket, edge)) {
31 /* Edge is already inserted. */
35 edge_bucket_insert(&edge_bucket, edge);
38 static void init_buckets(void)
42 edge_bucket_init(&edge_bucket);
43 node_bucket_init(&reduced_bucket);
45 for (i = 0; i < 4; ++i) {
46 node_bucket_init(&node_buckets[i]);
50 static void free_buckets(void)
54 for (i = 0; i < 4; ++i) {
55 node_bucket_free(&node_buckets[i]);
58 edge_bucket_free(&edge_bucket);
59 node_bucket_free(&reduced_bucket);
64 static void fill_node_buckets(pbqp *pbqp)
70 node_len = pbqp->num_nodes;
72 for (node_index = 0; node_index < node_len; ++node_index) {
74 pbqp_node *node = get_node(pbqp, node_index);
78 degree = pbqp_node_get_degree(node);
80 /* We have only one bucket for nodes with arity >= 3. */
85 node_bucket_insert(&node_buckets[degree], node);
91 static void normalize_towards_source(pbqp *pbqp, pbqp_edge *edge)
105 src_node = edge->src;
106 tgt_node = edge->tgt;
110 src_vec = src_node->costs;
111 tgt_vec = tgt_node->costs;
115 src_len = src_vec->len;
116 tgt_len = tgt_vec->len;
123 /* Normalize towards source node. */
124 for (src_index = 0; src_index < src_len; ++src_index) {
125 num min = pbqp_matrix_get_row_min(mat, src_index, tgt_vec);
128 if (src_vec->entries[src_index].data == INF_COSTS) {
129 pbqp_matrix_set_row_value(mat, src_index, 0);
131 pbqp_matrix_sub_row_value(mat, src_index, tgt_vec, min);
133 src_vec->entries[src_index].data = pbqp_add(
134 src_vec->entries[src_index].data, min);
136 if (min == INF_COSTS) {
138 unsigned edge_len = pbqp_node_get_degree(src_node);
140 for (edge_index = 0; edge_index < edge_len; ++edge_index) {
141 pbqp_edge *edge_candidate = src_node->edges[edge_index];
142 if (edge_candidate != edge) {
143 insert_into_edge_bucket(edge_candidate);
151 static void normalize_towards_target(pbqp *pbqp, pbqp_edge *edge)
165 src_node = edge->src;
166 tgt_node = edge->tgt;
170 src_vec = src_node->costs;
171 tgt_vec = tgt_node->costs;
175 src_len = src_vec->len;
176 tgt_len = tgt_vec->len;
183 for (tgt_index = 0; tgt_index < tgt_len; ++tgt_index) {
184 num min = pbqp_matrix_get_col_min(mat, tgt_index, src_vec);
187 if (tgt_vec->entries[tgt_index].data == INF_COSTS) {
188 pbqp_matrix_set_col_value(mat, tgt_index, 0);
190 pbqp_matrix_sub_col_value(mat, tgt_index, src_vec, min);
192 tgt_vec->entries[tgt_index].data = pbqp_add(
193 tgt_vec->entries[tgt_index].data, min);
195 if (min == INF_COSTS) {
197 unsigned edge_len = pbqp_node_get_degree(tgt_node);
199 for (edge_index = 0; edge_index < edge_len; ++edge_index) {
200 pbqp_edge *edge_candidate = tgt_node->edges[edge_index];
201 if (edge_candidate != edge) {
202 insert_into_edge_bucket(edge_candidate);
210 static void reorder_node(pbqp_node *node)
212 unsigned degree = pbqp_node_get_degree(node);
213 /* Assume node lost one incident edge. */
214 unsigned old_degree = degree + 1;
216 if (!buckets_filled) return;
218 /* Same bucket as before */
219 if (degree > 2) return;
221 if (!node_bucket_contains(node_buckets[old_degree], node)) {
222 /* Old arity is new arity, so we have nothing to do. */
223 assert(node_bucket_contains(node_buckets[degree], node));
227 /* Delete node from old bucket... */
228 node_bucket_remove(&node_buckets[old_degree], node);
230 /* ..and add to new one. */
231 node_bucket_insert(&node_buckets[degree], node);
234 static void check_melting_possibility(pbqp *pbqp, pbqp_edge *edge)
249 src_node = edge->src;
250 tgt_node = edge->tgt;
254 src_vec = src_node->costs;
255 tgt_vec = tgt_node->costs;
259 src_len = src_vec->len;
260 tgt_len = tgt_vec->len;
267 if (src_len == 1 && tgt_len == 1) {
268 //panic("Something is wrong");
272 for (src_index = 0; src_index < src_len; ++src_index) {
274 if (src_vec->entries[src_index].data == INF_COSTS) {
277 for (tgt_index = 0; tgt_index < tgt_len; ++tgt_index) {
278 if (tgt_vec->entries[tgt_index].data == INF_COSTS) {
281 if (mat->entries[src_index * tgt_len + tgt_index] == 0) {
290 if (mat->entries[src_index * tgt_len + tgt_index] == INF_COSTS) {
296 allRowsOk &= onlyOneZero;
300 for (tgt_index = 0; tgt_index < tgt_len; ++tgt_index) {
302 if (tgt_vec->entries[tgt_index].data == INF_COSTS) {
305 for (src_index = 0; src_index < src_len; ++src_index) {
306 if (src_vec->entries[src_index].data == INF_COSTS) {
309 if (mat->entries[src_index * tgt_len + tgt_index] == 0) {
318 if (mat->entries[src_index * tgt_len + tgt_index] == INF_COSTS) {
324 allColsOk &= onlyOneZero;
327 if (allRowsOk && allColsOk) {
332 static void simplify_edge(pbqp *pbqp, pbqp_edge *edge)
345 src_node = edge->src;
346 tgt_node = edge->tgt;
350 /* If edge are already deleted, we have nothing to do. */
351 if (!is_connected(src_node, edge) || !is_connected(tgt_node, edge))
354 if (pbqp->dump_file) {
356 sprintf(txt, "Simplification of Edge n%d-n%d", src_node->index, tgt_node->index);
357 dump_section(pbqp->dump_file, 3, txt);
360 src_vec = src_node->costs;
361 tgt_vec = tgt_node->costs;
365 src_len = src_vec->len;
366 tgt_len = tgt_vec->len;
373 if (pbqp->dump_file) {
374 fputs("Input:<br>\n", pbqp->dump_file);
375 dump_simplifyedge(pbqp, edge);
378 normalize_towards_source(pbqp, edge);
379 normalize_towards_target(pbqp, edge);
381 if (pbqp->dump_file) {
382 fputs("<br>\nOutput:<br>\n", pbqp->dump_file);
383 dump_simplifyedge(pbqp, edge);
386 if (pbqp_matrix_is_zero(mat, src_vec, tgt_vec)) {
387 if (pbqp->dump_file) {
388 fputs("edge has been eliminated<br>\n", pbqp->dump_file);
398 reorder_node(src_node);
399 reorder_node(tgt_node);
401 //check_melting_possibility(pbqp, edge);
405 static void initial_simplify_edges(pbqp *pbqp)
412 if (pbqp->dump_file) {
413 pbqp_dump_input(pbqp);
414 dump_section(pbqp->dump_file, 1, "2. Simplification of Cost Matrices");
417 node_len = pbqp->num_nodes;
421 /* First simplify all edges. */
422 for (node_index = 0; node_index < node_len; ++node_index) {
424 pbqp_node *node = get_node(pbqp, node_index);
431 edge_len = pbqp_node_get_degree(node);
433 for (edge_index = 0; edge_index < edge_len; ++edge_index) {
434 pbqp_edge *edge = edges[edge_index];
436 /* Simplify only once per edge. */
437 if (node != edge->src) continue;
439 simplify_edge(pbqp, edge);
444 static num determine_solution(pbqp *pbqp)
452 file = pbqp->dump_file;
455 dump_section(file, 1, "4. Determine Solution/Minimum");
456 dump_section(file, 2, "4.1. Trivial Solution");
459 /* Solve trivial nodes and calculate solution. */
460 node_len = node_bucket_get_length(node_buckets[0]);
464 pbqp->num_r0 = node_len;
468 for (node_index = 0; node_index < node_len; ++node_index) {
469 pbqp_node *node = node_buckets[0][node_index];
472 node->solution = vector_get_min_index(node->costs);
473 solution = pbqp_add(solution,
474 node->costs->entries[node->solution].data);
476 fprintf(file, "node n%d is set to %d<br>\n", node->index, node->solution);
477 dump_node(file, node);
482 dump_section(file, 2, "Minimum");
483 fprintf(file, "Minimum is equal to %lld.", solution);
489 static void back_propagate(pbqp *pbqp)
492 unsigned node_len = node_bucket_get_length(reduced_bucket);
495 if (pbqp->dump_file) {
496 dump_section(pbqp->dump_file, 2, "Back Propagation");
499 for (node_index = node_len; node_index > 0; --node_index) {
500 pbqp_node *node = reduced_bucket[node_index - 1];
502 switch (pbqp_node_get_degree(node)) {
504 back_propagate_RI(pbqp, node);
507 back_propagate_RII(pbqp, node);
510 panic("Only nodes with degree one or two should be in this bucket");
516 static void apply_heuristic_reductions(pbqp *pbqp)
519 if (edge_bucket_get_length(edge_bucket) > 0) {
521 } else if (node_bucket_get_length(node_buckets[1]) > 0) {
523 } else if (node_bucket_get_length(node_buckets[2]) > 0) {
525 } else if (node_bucket_get_length(node_buckets[3]) > 0) {
533 void solve_pbqp_heuristical(pbqp *pbqp)
535 /* Reduce nodes degree ... */
536 initial_simplify_edges(pbqp);
538 /* ... and put node into bucket representing their degree. */
539 fill_node_buckets(pbqp);
542 FILE *fh = fopen("solutions.pb", "a");
543 fprintf(fh, "Solution");
547 apply_heuristic_reductions(pbqp);
549 pbqp->solution = determine_solution(pbqp);
552 fh = fopen("solutions.pb", "a");
553 fprintf(fh, ": %lld RE:%u R0:%u R1:%u R2:%u RN/BF:%u\n", pbqp->solution,
554 pbqp->num_edges, pbqp->num_r0, pbqp->num_r1, pbqp->num_r2,
559 /* Solve reduced nodes. */
560 back_propagate(pbqp);
565 void apply_edge(pbqp *pbqp)
567 pbqp_edge *edge = edge_bucket_pop(&edge_bucket);
569 simplify_edge(pbqp, edge);
572 void apply_RI(pbqp *pbqp)
574 pbqp_node *node = node_bucket_pop(&node_buckets[1]);
575 pbqp_edge *edge = node->edges[0];
576 pbqp_matrix *mat = edge->costs;
577 int is_src = edge->src == node;
578 pbqp_node *other_node;
580 assert(pbqp_node_get_degree(node) == 1);
583 other_node = edge->tgt;
585 other_node = edge->src;
588 if (pbqp->dump_file) {
590 sprintf(txt, "RI-Reduction of Node n%d", node->index);
591 dump_section(pbqp->dump_file, 2, txt);
592 pbqp_dump_graph(pbqp);
593 fputs("<br>\nBefore reduction:<br>\n", pbqp->dump_file);
594 dump_node(pbqp->dump_file, node);
595 dump_node(pbqp->dump_file, other_node);
596 dump_edge(pbqp->dump_file, edge);
600 pbqp_matrix_add_to_all_cols(mat, node->costs);
601 normalize_towards_target(pbqp, edge);
603 pbqp_matrix_add_to_all_rows(mat, node->costs);
604 normalize_towards_source(pbqp, edge);
606 disconnect_edge(other_node, edge);
608 if (pbqp->dump_file) {
609 fputs("<br>\nAfter reduction:<br>\n", pbqp->dump_file);
610 dump_node(pbqp->dump_file, other_node);
613 reorder_node(other_node);
621 /* Add node to back propagation list. */
622 node_bucket_insert(&reduced_bucket, node);
625 void apply_RII(pbqp *pbqp)
627 pbqp_node *node = node_bucket_pop(&node_buckets[2]);
628 pbqp_edge *src_edge = node->edges[0];
629 pbqp_edge *tgt_edge = node->edges[1];
630 int src_is_src = src_edge->src == node;
631 int tgt_is_src = tgt_edge->src == node;
632 pbqp_matrix *src_mat;
633 pbqp_matrix *tgt_mat;
648 assert(pbqp_node_get_degree(node) == 2);
651 src_node = src_edge->tgt;
653 src_node = src_edge->src;
657 tgt_node = tgt_edge->tgt;
659 tgt_node = tgt_edge->src;
662 /* Swap nodes if necessary. */
663 if (tgt_node->index < src_node->index) {
675 src_is_src = src_edge->src == node;
676 tgt_is_src = tgt_edge->src == node;
679 if (pbqp->dump_file) {
681 sprintf(txt, "RII-Reduction of Node n%d", node->index);
682 dump_section(pbqp->dump_file, 2, txt);
683 pbqp_dump_graph(pbqp);
684 fputs("<br>\nBefore reduction:<br>\n", pbqp->dump_file);
685 dump_node(pbqp->dump_file, src_node);
686 dump_edge(pbqp->dump_file, src_edge);
687 dump_node(pbqp->dump_file, node);
688 dump_edge(pbqp->dump_file, tgt_edge);
689 dump_node(pbqp->dump_file, tgt_node);
692 src_mat = src_edge->costs;
693 tgt_mat = tgt_edge->costs;
695 src_vec = src_node->costs;
696 tgt_vec = tgt_node->costs;
697 node_vec = node->costs;
699 row_len = src_vec->len;
700 col_len = tgt_vec->len;
701 node_len = node_vec->len;
703 mat = pbqp_matrix_alloc(pbqp, row_len, col_len);
705 for (row_index = 0; row_index < row_len; ++row_index) {
706 for (col_index = 0; col_index < col_len; ++col_index) {
707 vec = vector_copy(pbqp, node_vec);
710 vector_add_matrix_col(vec, src_mat, row_index);
712 vector_add_matrix_row(vec, src_mat, row_index);
716 vector_add_matrix_col(vec, tgt_mat, col_index);
718 vector_add_matrix_row(vec, tgt_mat, col_index);
721 mat->entries[row_index * col_len + col_index] = vector_get_min(vec);
723 obstack_free(&pbqp->obstack, vec);
727 pbqp_edge *edge = get_edge(pbqp, src_node->index, tgt_node->index);
729 /* Disconnect node. */
730 disconnect_edge(src_node, src_edge);
731 disconnect_edge(tgt_node, tgt_edge);
739 /* Add node to back propagation list. */
740 node_bucket_insert(&reduced_bucket, node);
743 edge = alloc_edge(pbqp, src_node->index, tgt_node->index, mat);
745 pbqp_matrix_add(edge->costs, mat);
747 /* Free local matrix. */
748 obstack_free(&pbqp->obstack, mat);
750 reorder_node(src_node);
751 reorder_node(tgt_node);
754 if (pbqp->dump_file) {
755 fputs("<br>\nAfter reduction:<br>\n", pbqp->dump_file);
756 dump_edge(pbqp->dump_file, edge);
759 /* Edge has changed so we simplify it. */
760 simplify_edge(pbqp, edge);
763 static void select_alternative(pbqp_node *node, unsigned selected_index)
769 unsigned max_degree = pbqp_node_get_degree(node);
772 node->solution = selected_index;
773 node_vec = node->costs;
774 node_len = node_vec->len;
775 assert(selected_index < node_len);
777 /* Set all other costs to infinity. */
778 for (node_index = 0; node_index < node_len; ++node_index) {
779 if (node_index != selected_index) {
780 node_vec->entries[node_index].data = INF_COSTS;
784 /* Add all incident edges to edge bucket, since they are now independent. */
785 for (edge_index = 0; edge_index < max_degree; ++edge_index) {
786 insert_into_edge_bucket(node->edges[edge_index]);
790 static pbqp_node *get_node_with_max_degree(void)
792 pbqp_node **bucket = node_buckets[3];
793 unsigned bucket_len = node_bucket_get_length(bucket);
794 unsigned bucket_index;
795 unsigned max_degree = 0;
796 pbqp_node *result = NULL;
798 for (bucket_index = 0; bucket_index < bucket_len; ++bucket_index) {
799 pbqp_node *candidate = bucket[bucket_index];
800 unsigned degree = pbqp_node_get_degree(candidate);
802 if (degree > max_degree) {
811 static unsigned get_local_minimal_alternative(pbqp *pbqp, pbqp_node *node)
818 unsigned max_degree = 0;
821 unsigned min_index = 0;
827 node_vec = node->costs;
828 node_len = node_vec->len;
830 for (node_index = 0; node_index < node_len; ++node_index) {
831 num value = node_vec->entries[node_index].data;
833 for (edge_index = 0; edge_index < max_degree; ++edge_index) {
834 edge = node->edges[edge_index];
836 is_src = edge->src == node;
839 vec = vector_copy(pbqp, edge->tgt->costs);
840 vector_add_matrix_row(vec, mat, node_index);
842 vec = vector_copy(pbqp, edge->src->costs);
843 vector_add_matrix_col(vec, mat, node_index);
846 value = pbqp_add(value, vector_get_min(vec));
848 obstack_free(&pbqp->obstack, vec);
853 min_index = node_index;
860 void apply_RN(pbqp *pbqp)
862 pbqp_node *node = NULL;
863 unsigned min_index = 0;
867 /* We want to reduce a node with maximum degree. */
868 node = get_node_with_max_degree();
870 assert(pbqp_node_get_degree(node) > 2);
872 if (pbqp->dump_file) {
874 sprintf(txt, "RN-Reduction of Node n%d", node->index);
875 dump_section(pbqp->dump_file, 2, txt);
876 pbqp_dump_graph(pbqp);
879 min_index = get_local_minimal_alternative(pbqp, node);
881 if (pbqp->dump_file) {
882 fprintf(pbqp->dump_file, "node n%d is set to %d<br><br>\n",
883 node->index, min_index);
888 FILE *fh = fopen("solutions.pb", "a");
889 fprintf(fh, "[%u]", min_index);
895 /* Now that we found the local minimum set all other costs to infinity. */
896 select_alternative(node, min_index);
899 static void apply_brute_force_reductions(pbqp *pbqp)
902 if (edge_bucket_get_length(edge_bucket) > 0) {
904 } else if (node_bucket_get_length(node_buckets[1]) > 0) {
906 } else if (node_bucket_get_length(node_buckets[2]) > 0) {
908 } else if (node_bucket_get_length(node_buckets[3]) > 0) {
909 apply_Brute_Force(pbqp);
916 static unsigned get_minimal_alternative(pbqp *pbqp, pbqp_node *node)
921 unsigned min_index = 0;
923 unsigned bucket_index;
927 node_vec = node->costs;
928 node_len = node_vec->len;
929 bucket_index = node->bucket_index;
931 for (node_index = 0; node_index < node_len; ++node_index) {
932 pbqp_node_bucket bucket_deg3;
934 unsigned bucket_0_length;
935 unsigned bucket_red_length;
937 char *tmp = obstack_finish(&pbqp->obstack);
939 node_bucket_init(&bucket_deg3);
941 /* Some node buckets and the edge bucket should be empty. */
942 assert(node_bucket_get_length(node_buckets[1]) == 0);
943 assert(node_bucket_get_length(node_buckets[2]) == 0);
944 assert(edge_bucket_get_length(edge_bucket) == 0);
946 /* char *tmp = obstack_finish(&pbqp->obstack); */
948 /* Save current PBQP state. */
949 node_bucket_copy(&bucket_deg3, node_buckets[3]);
950 node_bucket_shrink(&node_buckets[3], 0);
951 node_bucket_deep_copy(pbqp, &node_buckets[3], bucket_deg3);
952 node_bucket_update(pbqp, node_buckets[3]);
953 bucket_0_length = node_bucket_get_length(node_buckets[0]);
954 bucket_red_length = node_bucket_get_length(reduced_bucket);
956 /* Select alternative and solve PBQP recursively. */
957 select_alternative(node_buckets[3][bucket_index], node_index);
958 apply_brute_force_reductions(pbqp);
960 value = determine_solution(pbqp);
964 min_index = node_index;
967 /* Some node buckets and the edge bucket should still be empty. */
968 assert(node_bucket_get_length(node_buckets[1]) == 0);
969 assert(node_bucket_get_length(node_buckets[2]) == 0);
970 assert(edge_bucket_get_length(edge_bucket) == 0);
972 /* Clear modified buckets... */
973 node_bucket_shrink(&node_buckets[3], 0);
975 /* ... and restore old PBQP state. */
976 node_bucket_shrink(&node_buckets[0], bucket_0_length);
977 node_bucket_shrink(&reduced_bucket, bucket_red_length);
978 node_bucket_copy(&node_buckets[3], bucket_deg3);
979 node_bucket_update(pbqp, node_buckets[3]);
982 /* obstack_free(&pbqp->obstack, tmp); */
983 node_bucket_free(&bucket_deg3);
985 obstack_free(&pbqp->obstack, tmp);
991 void apply_Brute_Force(pbqp *pbqp)
993 pbqp_node *node = NULL;
994 unsigned min_index = 0;
998 /* We want to reduce a node with maximum degree. */
999 node = get_node_with_max_degree();
1001 assert(pbqp_node_get_degree(node) > 2);
1003 if (pbqp->dump_file) {
1005 sprintf(txt, "BF-Reduction of Node n%d", node->index);
1006 dump_section(pbqp->dump_file, 2, txt);
1007 pbqp_dump_graph(pbqp);
1014 min_index = get_minimal_alternative(pbqp, node);
1015 node = pbqp->nodes[node->index];
1017 if (pbqp->dump_file) {
1018 fprintf(pbqp->dump_file, "node n%d is set to %d<br><br>\n",
1019 node->index, min_index);
1025 FILE *fh = fopen("solutions.pb", "a");
1026 fprintf(fh, "[%u]", min_index);
1032 /* Now that we found the minimum set all other costs to infinity. */
1033 select_alternative(node, min_index);
1036 void solve_pbqp_brute_force(pbqp *pbqp)
1038 /* Reduce nodes degree ... */
1039 initial_simplify_edges(pbqp);
1041 /* ... and put node into bucket representing their degree. */
1042 fill_node_buckets(pbqp);
1045 FILE *fh = fopen("solutions.pb", "a");
1046 fprintf(fh, "Solution");
1050 apply_brute_force_reductions(pbqp);
1052 pbqp->solution = determine_solution(pbqp);
1055 fh = fopen("solutions.pb", "a");
1056 fprintf(fh, ": %lld RE:%u R0:%u R1:%u R2:%u RN/BF:%u\n", pbqp->solution,
1057 pbqp->num_edges, pbqp->num_r0, pbqp->num_r1, pbqp->num_r2,
1062 /* Solve reduced nodes. */
1063 back_propagate(pbqp);
1068 void back_propagate_RI(pbqp *pbqp, pbqp_node *node)
1079 edge = node->edges[0];
1081 is_src = edge->src == node;
1088 /* Update pointer for brute force solver. */
1089 other = pbqp->nodes[other->index];
1091 vector_add_matrix_col(vec, mat, other->solution);
1096 /* Update pointer for brute force solver. */
1097 other = pbqp->nodes[other->index];
1099 vector_add_matrix_row(vec, mat, other->solution);
1102 node->solution = vector_get_min_index(vec);
1103 if (pbqp->dump_file) {
1104 fprintf(pbqp->dump_file, "node n%d is set to %d<br>\n", node->index, node->solution);
1108 void back_propagate_RII(pbqp *pbqp, pbqp_node *node)
1110 pbqp_edge *src_edge = node->edges[0];
1111 pbqp_edge *tgt_edge = node->edges[1];
1112 int src_is_src = src_edge->src == node;
1113 int tgt_is_src = tgt_edge->src == node;
1114 pbqp_matrix *src_mat;
1115 pbqp_matrix *tgt_mat;
1116 pbqp_node *src_node;
1117 pbqp_node *tgt_node;
1126 src_node = src_edge->tgt;
1128 src_node = src_edge->src;
1132 tgt_node = tgt_edge->tgt;
1134 tgt_node = tgt_edge->src;
1137 /* Swap nodes if necessary. */
1138 if (tgt_node->index < src_node->index) {
1139 pbqp_node *tmp_node;
1140 pbqp_edge *tmp_edge;
1142 tmp_node = src_node;
1143 src_node = tgt_node;
1144 tgt_node = tmp_node;
1146 tmp_edge = src_edge;
1147 src_edge = tgt_edge;
1148 tgt_edge = tmp_edge;
1150 src_is_src = src_edge->src == node;
1151 tgt_is_src = tgt_edge->src == node;
1154 /* Update pointer for brute force solver. */
1155 src_node = pbqp->nodes[src_node->index];
1156 tgt_node = pbqp->nodes[tgt_node->index];
1158 src_mat = src_edge->costs;
1159 tgt_mat = tgt_edge->costs;
1161 node_vec = node->costs;
1163 row_index = src_node->solution;
1164 col_index = tgt_node->solution;
1166 vec = vector_copy(pbqp, node_vec);
1169 vector_add_matrix_col(vec, src_mat, row_index);
1171 vector_add_matrix_row(vec, src_mat, row_index);
1175 vector_add_matrix_col(vec, tgt_mat, col_index);
1177 vector_add_matrix_row(vec, tgt_mat, col_index);
1180 node->solution = vector_get_min_index(vec);
1181 if (pbqp->dump_file) {
1182 fprintf(pbqp->dump_file, "node n%d is set to %d<br>\n", node->index, node->solution);
1185 obstack_free(&pbqp->obstack, vec);
1188 int node_is_reduced(pbqp_node *node)
1190 if (!reduced_bucket) return 0;
1192 if (pbqp_node_get_degree(node) == 0) return 1;
1194 return node_bucket_contains(reduced_bucket, node);